WO2012127299A1 - Foundry binder systems - Google Patents

Foundry binder systems Download PDF

Info

Publication number
WO2012127299A1
WO2012127299A1 PCT/IB2012/000539 IB2012000539W WO2012127299A1 WO 2012127299 A1 WO2012127299 A1 WO 2012127299A1 IB 2012000539 W IB2012000539 W IB 2012000539W WO 2012127299 A1 WO2012127299 A1 WO 2012127299A1
Authority
WO
WIPO (PCT)
Prior art keywords
solvent
triacetin
weight
binder system
mixture
Prior art date
Application number
PCT/IB2012/000539
Other languages
French (fr)
Inventor
Cristina Maria Schuch
Denilson José VICENTIM
Luciane Sereda
Suelbi Silva
Original Assignee
Rhodia Poliamida E Especialidades Ltda
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Rhodia Poliamida E Especialidades Ltda filed Critical Rhodia Poliamida E Especialidades Ltda
Priority to US14/001,241 priority Critical patent/US20140018468A1/en
Priority to BR112013023910A priority patent/BR112013023910A2/en
Priority to CN2012800142919A priority patent/CN103442824A/en
Priority to EP12718327.5A priority patent/EP2688698A1/en
Publication of WO2012127299A1 publication Critical patent/WO2012127299A1/en

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22C—FOUNDRY MOULDING
    • B22C1/00—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds
    • B22C1/16—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents
    • B22C1/20—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents of organic agents
    • B22C1/22—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents of organic agents of resins or rosins
    • B22C1/2233—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents of organic agents of resins or rosins obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
    • B22C1/2273—Polyurethanes; Polyisocyanates
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22C—FOUNDRY MOULDING
    • B22C1/00—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds
    • B22C1/16—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents
    • B22C1/20—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents of organic agents
    • B22C1/22—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents of organic agents of resins or rosins
    • B22C1/2233—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents of organic agents of resins or rosins obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
    • B22C1/2246—Condensation polymers of aldehydes and ketones
    • B22C1/2253—Condensation polymers of aldehydes and ketones with phenols
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/08—Processes
    • C08G18/0838—Manufacture of polymers in the presence of non-reactive compounds
    • C08G18/0842—Manufacture of polymers in the presence of non-reactive compounds in the presence of liquid diluents
    • C08G18/0847—Manufacture of polymers in the presence of non-reactive compounds in the presence of liquid diluents in the presence of solvents for the polymers
    • C08G18/0852—Manufacture of polymers in the presence of non-reactive compounds in the presence of liquid diluents in the presence of solvents for the polymers the solvents being organic
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/40—High-molecular-weight compounds
    • C08G18/54—Polycondensates of aldehydes
    • C08G18/542—Polycondensates of aldehydes with phenols

Definitions

  • the present invention relates to foundry binder systems forming a curable polyurethane with a catalytically effective amount of a curing catalyst, comprising at least one phenolic resin component comprising at least: a phenolic resin and a triacetin solvent of the phenolic resin and a polyisocyanate component.
  • the invention also relates to foundry mixes prepared from the binder and aggregate, foundry shapes such as cores and molds prepared by the cold or cold box processes, and the respective processes.
  • the foundry shapes obtained by the present invention are used in particular to manufacture metal parts, in particular for casting metal parts.
  • a conventional method used in the foundry industry to manufacture metal parts is sand casting.
  • disposable foundry shapes such as molds and cores, are produced by shaping and curing a foundry binder system which consists of a mixture of sand and binder.
  • the binder is used to strengthen mussels and cores.
  • the steps that follow the hardening of the binder are as follows:
  • the molten metal is poured to fill the hardened mold
  • the sand is eventually reused in another binder system.
  • Two of the main processes used in sand casting to produce molds and cores are the no-bake process and the cold box process.
  • a liquid curing agent is mixed with an aggregate, usually sand, and shaped to produce a cured mold and / or core.
  • the no-bake process is based on curing two or more binder components at room temperature after they have been combined with sand.
  • the curing of the binder system begins immediately after the addition of a liquid curing agent to all components, producing a cured mold and / or a core.
  • a gaseous curing agent is passed through a shaped compacted mixture to produce a cured mold and / or core.
  • the term "cold box process” involves the curing at room temperature of a mixture of binder and sand accelerated by a vapor or gas catalyst which has passed through the sand.
  • Polyurethane-forming binders cured with a tertiary amine gas catalyst, are often used in the cold box process to hold the foundry aggregates together in a mold or core form as described in US Pat. No. 3,409,579.
  • the polyurethane-forming binder system is generally comprised of a phenolic resin component and a polyisocyanate component that are mixed with sand prior to compacting and curing to form a casting binder system.
  • a solvent is that which is suitable both for the phenolic resin component and for the polyisocyanate component, and, if necessary, for other additives of the binder, for example, the hardening component. polyisocyanate.
  • the oldest class of solvents in this technology are probably those of aromatic hydrocarbon compounds, for example benzene, toluene, xylene and ethylbenzene.
  • Certain particular esters are also known as phenolic resin solvents used in polyurethane forming binder systems.
  • Some examples are dioctyl adipate and propylene glycol monomethyl ether acetate (WO 8907626), dibasic esters (WO9109908); ethyl acetate (EP1809456); methyl decanoate, methyl undecanoate and vinyl decanoate (RD425045); 1,2-diisobutylphthalate, dibasic esters and butyldiglycol acetate (EP1074568), dialkyl esters (US5,516,8, US 4,852,629).
  • esters that is to say the diesters of acetic acid such as glycerol triacetate (or triacetin, RN 102-76-1), glycerol diacetate (or diacetin, RN2539531-7), and glycerol monoacetate (or monoacetin, RN 26446-35-5), alone or in admixture with each other, are also known to be useful in foundry binding systems, but only in as curing agents, for example as described in JP4198531, US5602192, US5169880, US5043412, CS258845, JP03018530, US4468359, US3920460.
  • the typical content of triacetin as catalyst in the prior art is 0.5% by weight based on the weight of the phenolic resin.
  • the present invention relates to the discovery, undisclosed or suggested in the prior art, that triacetin or mixtures of mono-, di- and triacetin are useful solvents for phenolic resins in polyurethane-forming foundry binder systems, alone. or mixed with other solvents.
  • the present invention thus relates to the use of a mixture comprising at least triacetin as a solvent useful for phenolic resins in polyurethane-forming foundry binder systems, alone or in admixture with other solvents.
  • the present invention also relates to a curable polyurethane casting binder system with a catalytically effective amount of a curing catalyst comprising at least:
  • Another aspect of the present invention relates to foundry mixtures comprising components A and B above with an aggregate, for example sand.
  • the present invention relates to a method for preparing a foundry form by the cold box process or the non-baking process, which involves curing the molds and cores prepared with the binder above, or the foundry mix above.
  • the catalyst is in particular a tertiary amine.
  • the qualities of the triacetin solvent of the phenolic resin according to the present invention are as follows, in comparison with solvents of the prior art:
  • N2 nitrogen compounds
  • the solvent according to the invention thus comprises at least triacetin.
  • This triacetin can be obtained from a process using crude glycerine, such as, for example, the process described in patent application EP2272818.
  • the solvent may be a mixture comprising at least triacetin, and monoacetin and / or diacetin.
  • the solvent may be a mixture comprising at least 80% by weight of triacetin.
  • the mixture comprises triacetin, monoacetin and diacetin.
  • the solvent is a mixture of 80 to 95% by weight of triacetin, 5 to 15% by weight of diacetin and less than 5% by weight. monoacetin, based on the total weight of said mixture.
  • Triacetin has the formula (AcO) -CH 2 -CH (OAc) -CH 2 (OAc).
  • Diacetin has the formula (AcO) -CH 2 -CH (OH) -CH 2 (OAc).
  • Monoacetin has the formula (AcO) -CH 2 -CH (OH) -CH 2 (OH).
  • triacetin industrial triacetin is a mixture containing from 80 to 95% by weight of triacetin, 5 to 15% by weight of diacetin and less than 5% by weight of monoacetin, relative to the total weight of said mixture. It is advantageously used as a solvent for the phenolic resin in the foundry binder system according to the invention.
  • An appropriate mixture of solvents for phenolic resins according to the present invention without excluding any other, concerns triacetin and esters such as are known and generally used in this type of application.
  • examples that may be mentioned include dioctyl adipate and propylene glycol monomethyl ether acetate (WO 8907626), dibasic esters (WO9109908); ethyl acetate (EP1809456); methyl decanoate, methyl undecanoate and vinyl decanoate (RD425045); 1,2-diisobutylphthalate, dibasic esters and butyldiglycol acetate (EP1074568), dialkyl esters (US5,516,8, US4,852,629).
  • a particular suitable solvent mixture of phenolic resins according to the present invention includes triacetin and a mixture of dimethyl esters, for example that sold in Brazil under the trademark Rhodiasolv RPDE, comprising dimethyl adipate (RN 627-93-0), dimethyl glutarate (RN1119-40-0) and dimethyl succinate (RN 106-65-0), also used as a phenolic resin solvent useful in binding systems foundry forming polyurethane especially in the process without cooking or cold box.
  • Rhodiasolv RPDE dimethyl adipate
  • RN1119-40-0 dimethyl glutarate
  • RN 106-65-0 dimethyl succinate
  • adequate proportions of the triacetin solvent and said dimethyl ester mixture vary from 1:20 to 20: 1.
  • phenolic resin solvents for example aromatic hydrocarbons such as benzene, toluene, xylene, alkylbenzenes such as ethylbenzene, can also be used with triacetin, or with a mixture of solvents including triacetin and dimethyl esters.
  • the phenolic resin component of the present invention is used as a triacetin organic solvent solution, per se or with co-solvents.
  • Suitable phenolic resins are those which are known to those skilled in the art, solid or liquid, but soluble in organic solvents.
  • the amount of solvent used in component A should be sufficient to result in a binder composition that allows uniform coating thereof on the aggregate and uniform reaction of the mixture.
  • concentration of specific solvents varies according to the type of phenolic resin used and its molecular weight, the concentration of solvent in component A in general can be up to 60% by weight of the resin solution, being typically in the range of 10% to 40%, preferably 10 to 30%.
  • a particular phenolic resin used in sand casting according to the present invention is a phenolic resole resin, known as benzylic ether resole phenolic resins, prepared by reacting an excess of aldehyde with a phenol in the presence of a phenolic resin. alkaline catalyst or a metal catalyst. Without excluding others, the suitable phenolic resins are preferably substantially free of water. Examples of phenolic resins used in the compositions of the binders in question are well known in the art, such as those described in US Pat. No. 3,485,797. These resins mainly contain bridges connecting the phenolic rings of the polymer, which are ortho-ortho benzyl ether bridges.
  • phenols used to prepare resol phenol resins include one or more of the phenols which have hitherto been employed in the formation of phenolic resins and which are unsubstituted or at two positions. ortho either on an ortho position and on the para position. These unsubstituted positions are necessary for the polymerization reaction.
  • any of the remaining carbon atoms of the phenolic ring may be substituted.
  • the nature of the substituent can vary widely provided that the substituent does not seriously impair the polymerization of the aldehyde with phenol at the ortho and / or para position.
  • the substituted phenols used in the formation of phenolic resins include substituted alkyl phenols, substituted aryl phenols, substituted cycloalkyl phenols, substituted aryloxy phenols, and substituted halogenated phenols, which substituents contain from 1 to 26 carbon atoms and preferably from 1 to 12 carbon atoms.
  • Suitable phenols include phenol, 2,6-xylenol, o-cresol, p-cresol, 3,5-xylenol, 3,4-xylenol, 2,3,4-trimethyl phenol , 3-ethyl phenol, 3,5-diethyl phenol, p-butyl phenol, 3,5-dibutyl phenol, p-amyl phenol, p-cyclohexyl phenol, p-octyl phenol, 3,5 dicyclohexyl phenol, p-phenyl phenol, p-crotyl phenol, 3,5-dimethoxyphenol, 3,4,5-trimethoxyphenol, p-ethoxyphenol, p-butoxyphenol, 3-methyl -4-methoxy phenol, and p-phenoxy phenol. Phenols of multiple rings such as bisphenol A are also suitable.
  • Suitable aldehydes used to react with phenol to obtain a phenolic resole resin have the formula R-CHO where R is a hydrogen atom or a hydrocarbon radical with 1 to 8 carbon atoms.
  • the phenol-reactive aldehydes may include one of the aldehydes used hitherto in the formation of phenolic resins such as formaldehyde, acetaldehyde, propionaldehyde, furfuraldehyde, and benzaldehyde.
  • the polyisocyanate component of the binder of the present invention comprises a polyisocyanate, a polyisocyanate solvent and optional ingredients.
  • the polyisocyanate has a functionality of two or more, preferably from 2 to 5. It may be aliphatic, cycloaliphatic, aromatic, or a hybrid polyisocyanate.
  • the polyisocyanates may also be protected polyisocyanates, polyisocyanate prepolymers and quasi-prepolymers of polyisocyanates. Polyisocyanate blends are also covered by the present invention.
  • the polyisocyanate component of the foundry binder comprises a polyisocyanate, generally an organic polyisocyanate, and an organic solvent, generally comprising aromatic hydrocarbons, such as benzene, toluene, xylene and / or alkylbenzenes, in amounts typically ranging from from 0 percent by weight to about 80 percent by weight, based on the weight of the polyisocyanate.
  • aromatic hydrocarbons such as benzene, toluene, xylene and / or alkylbenzenes
  • Optional ingredients such as release agents and life extenders may also be used in the polyisocyanate component.
  • polyisocyanates used in the present invention are aliphatic polyisocyanates such as hexamethylene diisocyanate, alicyclic polyisocyanates such as 4,4'-dicyclohexylmethane diisocyanate, and aromatic polyisocyanates such as 2,4 and 2 , 6-toluene diisocyanate, diphenylmethane diisocyanate, and their dimethyl derivatives.
  • polyisocyanates are 1,5-naphthalene diisocyanate, triphenylmethane triisocyanate, xylylene, and their methyl derivatives, polymethylenepolyphenyl isocyanates, chlorophenylene-2,4-diisocyanate, and the like.
  • the polyisocyanates are used in concentrations sufficient to cause curing of the resin after gas passage or when in contact with the liquid curing catalyst.
  • the ratio of the polyisocyanate to the hydroxyl of the phenolic resin is 1.25: 1 to 1: 1, 25.
  • the amount of polyisocyanate used is generally from 10 to 500 percent by weight, based on the weight of the phenolic resin.
  • Suitable polyisocyanates are used in particular in liquid form, which can be used in undiluted form, while solid or viscous polyisocyanates are used in the form of organic solvent solutions.
  • suitable solvents for polyisocyanate are AB9 and AB10 (alkylbenzene compounds containing an alkyl substituent which comprises respectively 9 and 10 carbon atoms, for example sold under the trade name Solvesso 100).
  • aromatic solvents of the polyisocyanates include benzene, toluene, xylene, alkyl benzenes and mixtures thereof.
  • the aromatic solvents are preferably a mixture of aromatic solvents whose boiling point ranges from 125 ° C to 250 ° C.
  • the polar solvents must not be extremely polar, which would make them incompatible with the aromatic solvent.
  • Suitable polar solvents are generally those which are classified in the art as coupling solvents and include furfural, furfuryl alcohol, 2-ethoxyethyl acetate (Cellosolve TM acetate), 2-butoxyethanol (butyl Cellosolve TM), monobutyl ether diethylene glycol (butyl Carbitol TM), diacetone alcohol, and 2,2,4-trimethyl-1,3-diol monoisobutyrate (Texanol TM). Cellosolve, Carbitol, and Texanol are trade names.
  • the polyisocyanate component B optionally comprises an aromatic hydrocarbon compound.
  • An optional element for a polyurethane forming binder system is a natural oil.
  • the natural oil is used in the phenolic resin component, the isocyanate component, or both, in an effective amount sufficient to improve the tensile strength of the binder-based foundry forms. This amount is generally from about 1 percent by weight to about 15 percent by weight, based on the weight of the isocyanate component. In general, lesser amounts of natural oil are used in the phenolic resin component, generally from about 1 percent by weight to about 5 percent by weight, based on the weight of the phenolic resin. Compatible natural oils are also adequate.
  • a natural oil is considered compatible with organic isocyanate and / or phenolic resin if the mixture does not separate in two phases at room temperature, and preferably if it does not separate at temperatures between 30 ° C at 0 ° C.
  • Natural oils include unmodified natural oils and their various known modifications, for example heat-thickened oils blown with air or oxygen, such as flaxseed oil and oil. Soy soufflé. They are generally classified as esters of ethylenically unsaturated fatty acids. The proper viscosities of the natural oil range from A to J according to the Gardner Holt viscosity index.
  • the acidity value of the natural oil varies typically from 0 to 10, as measured by the number of milligrams of potassium hydroxide required to neutralize a sample of 1 gram of natural oil.
  • Representative examples of the natural oils that are used in the isocyanate component include linseed oil, including refined linseed oil, epoxidized linseed oil, linseed oil refined with alkali, soybean oil, cottonseed oil, RBD (refined, bleached and deodorized) canola oil, refined sunflower oil, tung oil and dehydrated castor oil.
  • Particularly used natural oils include more pure forms of natural oils which are treated to remove fatty acids and other impurities, generally consisting of triglycerides and less than 1 percent by weight of impurities such as fatty acids and other impurities.
  • Particular examples of such pure natural oils include Polymerized Linseed Oils (PLO) such as Supreme Linseed Oil with an acid value of about 0.30 and a maximum viscosity of A and soybean oils.
  • Purified oils such as refined soybean oil having an acid value of less than 0.1 and a viscosity of A to B. As is already known, this increases the tensile forces of foundry shapes.
  • drying oils as described in US Pat. No. 4,268,425 can be included in the binder in one of the solvents mentioned herein. These drying oils comprise fatty acid glycerides containing two or more double bonds. In addition, ethylenically unsaturated fatty acid esters such as pine oil esters of polyhydric or monohydric alcohols can be used as the drying oil. Generally, the drying oils are used at about 35% to about 50% by weight of the total amount of solvent.
  • the binder may also contain a silane, generally added to the phenolic resin component, for example as described in US6288139. For example, the silane is added to the phenolic resin component in amounts of 0.01 to 2 percent by weight, based on the weight of the phenolic resin.
  • ordinary sand-type foundry shapes refers to foundry shapes that have sufficient porosity to permit evacuation of volatiles during the casting operation.
  • at least about 80% by weight of the aggregates used for foundry shapes have an average particle size of not less than about 50 and about 50 mesh (Tyler Screen Mesh).
  • a suitable aggregate used for ordinary foundry shapes is silica in which about 70% by weight of the sand is silica.
  • Other suitable materials include zircon, olivine, aluminosilicate, sand, chromite sand, and the like. Although the best results are often obtained when the aggregate used is dry, it may contain small amounts of moisture.
  • the aggregate constitutes the main constituent, the binder being present in a relatively small amount.
  • the amount of binder does not generally exceed about 10% by weight and is frequently in the range of 0.5 to 7% by weight based on the weight of the aggregate, particularly 0 to 1, 8%.
  • the binder compositions are preferably provided as a double package system with the phenolic resin component in one package and the polyisocyanate component in the other.
  • the phenolic resin component is mixed with the aggregate, and then the polyisocyanate component is added. Binder distribution methods on aggregate particles are well known to those skilled in the art.
  • Another aspect of the present invention relates to methods for obtaining sand casting forms, using the novel binder system, which is molded into the desired shape, such as a mold or core, and cured.
  • Curing by the cold box process is carried out by passing a tertiary volatile amine, for example triethylamine, 1-dimethylamino-2-propanol (DMA-2P), monoethanolamine or dimethylaminopropylamine (DMAPA), through the form in the mold as described in US Patent 3,409,579.
  • Curing by the non-firing process is performed by mixing a liquid amine curing catalyst in the foundry binder system, which is then shaped, and set to cure.
  • the term "catalytically effective amount of a curing catalyst” a concentration of the catalyst preferably between 0.2 and 5.0 percent by weight of the phenolic resin.
  • the useful liquid curing catalyst amines have a pKb value generally of the order of 7 to 11. Particular examples of these amines include 4-alkylpyridines, isoquinoline, arylpyridines, 1-methylbenzimidazole, and 1,4-thiazine.
  • a tertiary liquid amine particularly used as catalyst is an aliphatic tertiary amine such as tris (3-dimethylamino) propylamine).
  • the concentration of the liquid amine catalyst ranges from 0.2 to 5.0 percent by weight of the phenolic resin, in particular from 1.0 to 4.0 percent by weight, more preferably 2.0. to 3.5 percent by weight based on the weight of the polyether polyol.
  • Catalysts such as triethylamine or dimethylethylamine are used in a range of 0.05 to 0.15 percent by weight based on the weight of the binder.
  • the solubilization power of the solvents tested in this example was determined by simulation using Solsys ® software (Rhodia). It is based on Hansen's solubility parameter theory and three-dimensional system. As it is in fact known to those skilled in the art, the most widely used cohesion energy parameters for the characterization of solvents are those developed by Hansen (for example in the work "Hansen Solubility Parameters: A user's handbook”. Hansen, Charles Second Edition 2007 Boca Raton, FL, USA (CRC Press). There are three numbers that together are called HSPs. They fully describe how a solvent behaves relative to what is dissolved if their HSPs are known or can be estimated:
  • the technique for determining the solubility parameters D, P, H of a substance consists in testing the solubility of said substance in a series of pure solvents which belong to different chemical groups (for example, hydrocarbons, ketones, esters, alcohols and glycols). The evaluation is made by considering the solvents which completely solubilize, partially or do not solubilize the substance to be solubilized.
  • the Solsys® Software is used to determine the solubility volume of the substance and as a result it determines the best solvent for dissolving the substance.
  • the volume of solubility is represented by a sphere (three-dimensional system) whose center corresponds to a "standardized distance" equal to 0 and represents the maximum of solubility.
  • the set of points on the surface of the sphere correspond to a "standardized distance” equal to 1 and reflect the limit of solubility.
  • the sphere is represented on a graph whose axes correspond to ⁇ D, ⁇ and ⁇ .
  • the solubility of the resin in the solvent will be all the better that the volume of solubility will be close to the center (normalized distance equal to 0). Beyond the surface of the sphere (normalized distance equal to 1), the resin is no longer soluble in the solvent.
  • Standardized distance values are used to evaluate the solubilizing power of a substance, i.e. phenolic resin in this case, in a solvent. The more the value of the normalized distance is close to zero, the more the resin is soluble in the solvent. Table I below shows the solubility parameter values of a commercial mixture of dimethyl esters, compared with triacetin with purity higher than 99.5% and industrial triacetin. Standardized distances were obtained for a phenolic resole resin. TABLE I
  • solubility parameter values for the commercial dimethyl ester solvent mixture are similar to those obtained for triacetin. This means that the solvents are partially or totally interchangeable for most applications, especially in blending, which depends on commercial conditions. Standard distances are also very close, especially for solubility in RPDE and triacetin with purity higher than 99.5%.

Abstract

The present invention relates to foundry binder systems forming a polyurethane that can be hardened with a catalytically effective amount of a hardening catalyst, comprising at least one phenolic resin component comprising at least: a phenolic resin and a solvent of triacetin type and a polyisocyanate component. The invention also relates to foundry mixes prepared from binder and an aggregate, foundry forms such as cores and moulds prepared by no-bake or cold-box processes, and also the respective processes. The foundry forms obtained by the present invention are in particular used for manufacturing metal parts, especially for casting metal parts.

Description

SYSTÈMES LIANTS DE FONDERIE  FOUNDRY BINDING SYSTEMS
La présente invention concerne des systèmes de liant de fonderie formant un polyuréthane durcissable avec une quantité catalytiquement efficace d'un catalyseur de durcissement, comprenant au moins un composant résine phénolique comprenant au moins: une résine phénolique et un solvant de type triacétine de la résine phénolique et un composant polyisocyanate. L'invention concerne également des mélanges de fonderie préparés à partir du liant et d'un agrégat, des formes de fonderie telles que les noyaux et les moules préparées par les procédés sans cuisson ou en boîte froide, ainsi que les procédés respectifs. Les formes de fonderie obtenues par la présente invention sont notamment utilisées pour fabriquer des pièces métalliques, notamment pour le coulage de pièces métalliques. The present invention relates to foundry binder systems forming a curable polyurethane with a catalytically effective amount of a curing catalyst, comprising at least one phenolic resin component comprising at least: a phenolic resin and a triacetin solvent of the phenolic resin and a polyisocyanate component. The invention also relates to foundry mixes prepared from the binder and aggregate, foundry shapes such as cores and molds prepared by the cold or cold box processes, and the respective processes. The foundry shapes obtained by the present invention are used in particular to manufacture metal parts, in particular for casting metal parts.
ARRIÈRE-PLAN DE L'INVENTION BACKGROUND OF THE INVENTION
Un procédé classique utilisé dans l'industrie de la fonderie pour fabriquer des pièces métalliques est la coulée en sable. Dans la coulée en sable des formes de fonderie jetables, tels que les moules et les noyaux, sont produites par mise en forme et le durcissement d'un système liant de fonderie qui est constitué d'un mélange de sable et de liant. Le liant est utilisé pour renforcer les moules et les noyaux. Les étapes qui succèdent le durcissement du liant sont les suivantes:  A conventional method used in the foundry industry to manufacture metal parts is sand casting. In sand casting disposable foundry shapes, such as molds and cores, are produced by shaping and curing a foundry binder system which consists of a mixture of sand and binder. The binder is used to strengthen mussels and cores. The steps that follow the hardening of the binder are as follows:
- le métal fondu est versé pour remplir le moule durci, the molten metal is poured to fill the hardened mold,
la coulée est refroidie,  the casting is cooled,
la coulée ainsi obtenue est retirée, et le moule correspondant est détruit,  the casting thus obtained is removed, and the corresponding mold is destroyed,
le sable est éventuellement réutilisé dans un autre système liant.  the sand is eventually reused in another binder system.
Deux des principaux procédés utilisés dans la coulée en sable pour produire des moules et des noyaux sont les procédé sans cuisson (« no-bake ») et le procédé en boîte froide (« cold box »). Dans le procédé sans cuisson, un agent liquide de durcissement est mélangé avec un agrégat, généralement du sable, et mis en forme pour produire un moule et/ou un noyau durci. Le procédé sans cuisson est fondé sur le durcissement à la température ambiante de deux ou plusieurs composants de liant après qu'ils ont été combinés avec du sable. Le durcissement du système liant commence immédiatement après l'addition d'un agent de durcissement liquide à tous les composants, produisant un moule durci et/ou un noyau. Dans le procédé en boîte froide, un agent de durcissement gazeux est passé à travers un mélange compacté mis en forme afin de produire un moule et/ou un noyau durci. Le terme « procédé en boîte froide » implique le durcissement à la température ambiante d'un mélange de liant et de sable accéléré par un catalyseur en vapeur ou gazeaux qui est passé à travers le sable. Les liants formant du polyuréthane, durcis avec un catalyseur aminé tertiaire gazeuse, sont souvent utilisés dans le procédé en boîte froide pour maintenir les agrégats de fonderie ensemble sous forme de moule ou de noyau tel que décrit dans le document de brevet américain US3,409,579. Le système liant formant du polyuréthane est généralement constitué d'un composant résine phénolique et d'un composant polyisocyanate qui sont mélangés avec du sable avant le compactage et le durcissement pour former un système liant de fonderie. Two of the main processes used in sand casting to produce molds and cores are the no-bake process and the cold box process. In the uncured process, a liquid curing agent is mixed with an aggregate, usually sand, and shaped to produce a cured mold and / or core. The no-bake process is based on curing two or more binder components at room temperature after they have been combined with sand. The curing of the binder system begins immediately after the addition of a liquid curing agent to all components, producing a cured mold and / or a core. In the cold box process, a gaseous curing agent is passed through a shaped compacted mixture to produce a cured mold and / or core. The term "cold box process" involves the curing at room temperature of a mixture of binder and sand accelerated by a vapor or gas catalyst which has passed through the sand. Polyurethane-forming binders, cured with a tertiary amine gas catalyst, are often used in the cold box process to hold the foundry aggregates together in a mold or core form as described in US Pat. No. 3,409,579. The polyurethane-forming binder system is generally comprised of a phenolic resin component and a polyisocyanate component that are mixed with sand prior to compacting and curing to form a casting binder system.
L'homme du métier sait que la meilleure utilisation d'un solvant est celle qui convient aussi bien au composant résine phénolique qu'au composant polyisocyanate, et, au besoin, à d'autres additifs du liant, par exemple, le composant de durcissement du polyisocyanate. The person skilled in the art knows that the best use of a solvent is that which is suitable both for the phenolic resin component and for the polyisocyanate component, and, if necessary, for other additives of the binder, for example, the hardening component. polyisocyanate.
La plus ancienne classe de solvants dans cette technologie est probablement celles des composés hydrocarbonés aromatiques, par exemple le benzène, le toluène, le xylène et l'éthylbenzène. Certains esters particuliers sont également connus en tant que solvants de la résine phénolique utilisée dans les systèmes liants de fonderie formant du polyuréthane. Quelques exemples en sont l'adipate de dioctyle et l'acétate le propylène glycol monométhyléther (WO8907626), les esters dibasiques (W09109908); l'acétate d'éthyle (EP1809456); le décanoate de méthyle, l'undécanoate de méthyle et le décanoate de vinyle (RD425045); le 1 ,2- diisobutylphthalate, les esters dibasiques et l'acétate de butyldiglycol (EP1074568), les esters de dialkyle (US5, 516,8, US4,852,629). D'autre part, une autre classe d'esters, c'est-à-dire les diesters de l'acide acétique tels que le triacétate de glycérol (ou triacétine, RN 102-76-1), le diacétate de glycérol (ou diacétine, RN2539531-7), et le monoacétate de glycérol (ou monoacétine, RN 26446-35-5), seuls ou en mélange entre eux, sont également connus comme susceptibles d'être utilisés dans les systèmes liants de fonderie, mais uniquement en tant qu'agents de durcissement, par exemple tel que décrit dans les documents de brevets JP4198531 , US5602192, US5169880, US5043412, CS258845, JP03018530, US4468359, US3920460. La teneur typique de triacétine comme catalyseur dans l'art antérieur est de 0,5% en poids par rapport au poids de la résine phénolique. The oldest class of solvents in this technology are probably those of aromatic hydrocarbon compounds, for example benzene, toluene, xylene and ethylbenzene. Certain particular esters are also known as phenolic resin solvents used in polyurethane forming binder systems. Some examples are dioctyl adipate and propylene glycol monomethyl ether acetate (WO 8907626), dibasic esters (WO9109908); ethyl acetate (EP1809456); methyl decanoate, methyl undecanoate and vinyl decanoate (RD425045); 1,2-diisobutylphthalate, dibasic esters and butyldiglycol acetate (EP1074568), dialkyl esters (US5,516,8, US 4,852,629). On the other hand, another class of esters, that is to say the diesters of acetic acid such as glycerol triacetate (or triacetin, RN 102-76-1), glycerol diacetate (or diacetin, RN2539531-7), and glycerol monoacetate (or monoacetin, RN 26446-35-5), alone or in admixture with each other, are also known to be useful in foundry binding systems, but only in as curing agents, for example as described in JP4198531, US5602192, US5169880, US5043412, CS258845, JP03018530, US4468359, US3920460. The typical content of triacetin as catalyst in the prior art is 0.5% by weight based on the weight of the phenolic resin.
INVENTION INVENTION
La présente invention concerne la découverte, non divulguée ou suggéré dans l'art antérieur, que la triacétine ou des mélanges de mono-, di- et triacétine sont des solvants utiles pour les résines phénoliques dans les systèmes liants de fonderie formant du polyuréthane, seuls ou en mélange avec d'autres solvants.  The present invention relates to the discovery, undisclosed or suggested in the prior art, that triacetin or mixtures of mono-, di- and triacetin are useful solvents for phenolic resins in polyurethane-forming foundry binder systems, alone. or mixed with other solvents.
La présente invention concerne ainsi l'utilisation d'un mélange comprenant au moins de la triacétine comme solvant utile pour les résines phénoliques dans les systèmes liants de fonderie formant du polyuréthane, seuls ou en mélange avec d'autres solvants. La présente invention concerne aussi un système liant de fonderie de polyuréthane durcissable avec une quantité catalytiquement efficace d'un catalyseur de durcissement comprenant au moins: The present invention thus relates to the use of a mixture comprising at least triacetin as a solvent useful for phenolic resins in polyurethane-forming foundry binder systems, alone or in admixture with other solvents. The present invention also relates to a curable polyurethane casting binder system with a catalytically effective amount of a curing catalyst comprising at least:
A. un composant résine phénolique comprenant au moins:  A. a phenolic resin component comprising at least:
(1) une résine phénolique; et (1) a phenolic resin; and
(2) un solvant comprenant au moins de la triacétine ; et  (2) a solvent comprising at least triacetin; and
B. un composant polyisocyanate. B. a polyisocyanate component.
Un autre aspect de la présente invention concerne les mélanges de fonderie comprenant les composants A et B ci-dessus avec un agrégat, par exemple le sable. Another aspect of the present invention relates to foundry mixtures comprising components A and B above with an aggregate, for example sand.
Dans un autre aspect encore, la présente invention porte sur un procédé pour préparer une forme de fonderie par le procédé en boîte froide ou par le procédé sans cuisson, ce qui implique le durcissement des moules et des noyaux préparés avec le liant ci-dessus, ou le mélange de fonderie ci-dessus. In still another aspect, the present invention relates to a method for preparing a foundry form by the cold box process or the non-baking process, which involves curing the molds and cores prepared with the binder above, or the foundry mix above.
Dans le procédé en boîte froide, le catalyseur est en particulier une aminé tertiaire. In the cold box process, the catalyst is in particular a tertiary amine.
Les qualités du solvant triacétine de la résine phénolique selon la présente invention sont les suivants, en comparaison avec des solvants de l'art antérieur : The qualities of the triacetin solvent of the phenolic resin according to the present invention are as follows, in comparison with solvents of the prior art:
Compatibilité avec la résine phénolique.  Compatibility with phenolic resin.
Absence de composés azotés (N2), qui contribuent à la production de gaz lors de la coulée, engendrant ainsi l'apparition de défauts dans la pièce métallique.  Absence of nitrogen compounds (N2), which contribute to the production of gas during casting, thus causing the appearance of defects in the metal part.
Accélération du processus de catalyse de la réaction entre la résine phénolique et le polyisocyanate.  Acceleration of the catalysis process of the reaction between the phenolic resin and the polyisocyanate.
Absence ou faible teneur de OH-, qui réagit avec du polyisocyanate (par exemple MDI) et favorise la perte de propriétés. Faible hygroscopicité, diminuant la possibilité de réaction entre l'eau et un polyisocyanate, favorisant la perte de propriétés, ou la génération de gaz lors de la coulée, engendrant ainsi l'apparition de défauts dans la pièce métallique Absence or low content of OH-, which reacts with polyisocyanate (eg MDI) and promotes the loss of properties. Low hygroscopicity, reducing the possibility of reaction between water and a polyisocyanate, favoring the loss of properties, or gas generation during casting, thus causing the appearance of defects in the metal part
Point éclair supérieur à 120°C, ce qui réduit d'inflammabilité  Flash point above 120 ° C, reducing flammability
- Faible teneur en composés organiques volatiles - Low content of volatile organic compounds
Faible émission de fumée ; la fumée engendranr des défauts dans la partie métallique  Low smoke emission the smoke generates defects in the metal part
Solvabilité: la viscosité du mélange résine + solvant est suffisante pour assurer l'enrobage du sable  Solvency: the viscosity of the resin + solvent mixture is sufficient to ensure the coating of the sand
- Très faible dégagement d'odeur - Very low odor
Facilement biodégradable  Easily biodegradable
Non biocumulative  Non-bioaccumulative
Non classé comme cancérogène  Not classified as a carcinogen
Non classé comme mutagène  Not classified as mutagenic
- Faible toxicité aquatique - Low aquatic toxicity
Pratiquement non irritant pour les yeux ou la peau  Virtually non-irritating to the eyes or skin
Les composés chimiques mentionnés dans ce texte, tels que la triacétine, doivent être utilisés avec soin et précaution dans le procédé de la présente invention, selon les normes techniques. The chemical compounds mentioned in this text, such as triacetin, must be used with care and care in the process of the present invention, according to technical standards.
Solvant Solvent
Le solvant selon l'invention comprend ainsi au moins de la triacétine. Cette triacétine peut être obtenue à partir d'un procédé utilisant de la glycérine brute, tel que par exemple le procédé décrit dans la demande de brevet EP2272818. Le solvant peut être un mélange comprenant au moins de la triacétine, et de la monoacétine et/ou de la diacétine. Le solvant peut être un mélange comprenant au moins 80 % en poids de triacétine. Préférentiellement le mélange comprend de la triacétine, de la monoacétine et de la diacétine.  The solvent according to the invention thus comprises at least triacetin. This triacetin can be obtained from a process using crude glycerine, such as, for example, the process described in patent application EP2272818. The solvent may be a mixture comprising at least triacetin, and monoacetin and / or diacetin. The solvent may be a mixture comprising at least 80% by weight of triacetin. Preferably, the mixture comprises triacetin, monoacetin and diacetin.
Dans un mode de réalisation particulier, le solvant est un mélange de 80 à 95% en poids de triacétine, 5 à 15% en poids de diacétine et moins de 5% en poids de monoacétine, par rapport au poids total dudit mélange. La triacétine présente la formule (AcO)-CH2-CH(OAc)-CH2(OAc). La diacétine présente la formule (AcO)-CH2-CH(OH)-CH2(OAc). La monoacétine présente la formule (AcO)-CH2- CH(OH)-CH2(OH). Dans les formules ci-dessus, Ac désigne CH3C(=0). La triacétine dite « triacétine industrielle » est un mélange contenant de 80 à 95% en poids de triacétine, 5 à 15% en poids de diacétine et moins de 5% en poids de monoacétine, par rapport au poids total dudit mélange. Elle est avantageusement utilisée comme solvant pour la résine phénolique dans le système liant de fonderie selon l'invention. In a particular embodiment, the solvent is a mixture of 80 to 95% by weight of triacetin, 5 to 15% by weight of diacetin and less than 5% by weight. monoacetin, based on the total weight of said mixture. Triacetin has the formula (AcO) -CH 2 -CH (OAc) -CH 2 (OAc). Diacetin has the formula (AcO) -CH 2 -CH (OH) -CH 2 (OAc). Monoacetin has the formula (AcO) -CH 2 -CH (OH) -CH 2 (OH). In the formulas above, Ac denotes CH 3 C (= 0). The so-called "triacetin industrial triacetin" is a mixture containing from 80 to 95% by weight of triacetin, 5 to 15% by weight of diacetin and less than 5% by weight of monoacetin, relative to the total weight of said mixture. It is advantageously used as a solvent for the phenolic resin in the foundry binder system according to the invention.
Un mélange adéquat de solvants pour résines phénoliques selon la présente invention, sans exclure n'importe quel autre, concerne la triacétine et les esters tels ceux qui sont connus et généralement utilisés dans ce genre d'application. On peut citer comme exemples l'adipate de dioctyle et l'acétate de propylène glycol monométhyléther (WO8907626), les esters dibasiques (WO9109908); l'acétate d'éthyle (EP1809456); le décanoate de méthyle, l'undécanoate de méthyle et le décanoate de vinyle (RD425045); le 1 ,2-diisobutylphthalate, les esters dibasiques et l'acétate de butyldiglycol (EP1074568), les esters de dialkyle (US5, 516,8, US4, 852,629). An appropriate mixture of solvents for phenolic resins according to the present invention, without excluding any other, concerns triacetin and esters such as are known and generally used in this type of application. Examples that may be mentioned include dioctyl adipate and propylene glycol monomethyl ether acetate (WO 8907626), dibasic esters (WO9109908); ethyl acetate (EP1809456); methyl decanoate, methyl undecanoate and vinyl decanoate (RD425045); 1,2-diisobutylphthalate, dibasic esters and butyldiglycol acetate (EP1074568), dialkyl esters (US5,516,8, US4,852,629).
Un mélange de solvants adéquat particulier de résines phénoliques selon la présente invention, sans exclure n'importe quel autre, comprend la triacétine et un mélange d'esters de diméthyle, par exemple celui qui est vendu au Brésil sous la marque Rhodiasolv RPDE, comprenant l'adipate de diméthyle (RN 627- 93 -0), le glutarate de diméthyle (RN1119-40-0) et le succinate de diméthyle (RN 106-65-0), également utilisé comme solvant de résine phénolique utile dans les systèmes liants de fonderie formant du polyuréthane en particulier dans le procédé sans cuisson ou en boîte froide. Sans pour autant exclure d'autres, les proportions adéquates entre le solvant triacétine et ledit mélange d'ester de diméthyle varie de 1 :20 à 20 :1. Selon la présente invention, d'autres solvants de résines phénoliques, par exemple les hydrocarbures aromatiques comme le benzène, le toluène, le xylène, les alkyl-benzènes comme l'éthylbenzène, peuvent également être utilisé avec la triacètine, ou avec un mélange de solvants comprenant triacètine et esters de diméthyle. A particular suitable solvent mixture of phenolic resins according to the present invention, without excluding any other, includes triacetin and a mixture of dimethyl esters, for example that sold in Brazil under the trademark Rhodiasolv RPDE, comprising dimethyl adipate (RN 627-93-0), dimethyl glutarate (RN1119-40-0) and dimethyl succinate (RN 106-65-0), also used as a phenolic resin solvent useful in binding systems foundry forming polyurethane especially in the process without cooking or cold box. Without excluding others, adequate proportions of the triacetin solvent and said dimethyl ester mixture vary from 1:20 to 20: 1. According to the present invention, other phenolic resin solvents, for example aromatic hydrocarbons such as benzene, toluene, xylene, alkylbenzenes such as ethylbenzene, can also be used with triacetin, or with a mixture of solvents including triacetin and dimethyl esters.
Résine phénolique Phenolic resin
Le composant résine phénolique de la présente invention est utilisé comme une solution de solvant organique de triacètine, en soi ou avec des co-solvants.  The phenolic resin component of the present invention is used as a triacetin organic solvent solution, per se or with co-solvents.
Les résines phénoliques adéquates sont celles qui sont connues de l'homme de l'art, solides ou liquides, mais solubles dans les solvants organiques. La quantité de solvant utilisé dans le composant A doit être suffisante pour résulter en une composition de liant permettant un revêtement uniforme de celle-ci sur l'agrégat et une réaction uniforme du mélange. Malgré le fait que la concentration de solvants spécifiques varie selon le type de résine phénolique utilisé et son poids moléculaire, la concentration en solvant dans le composant A en général, peut aller jusqu'à 60% en poids de la solution de résine, se situant typiquement dans la gamme de 10% à 40%, de préférence de 10 à 30%. Suitable phenolic resins are those which are known to those skilled in the art, solid or liquid, but soluble in organic solvents. The amount of solvent used in component A should be sufficient to result in a binder composition that allows uniform coating thereof on the aggregate and uniform reaction of the mixture. Despite the fact that the concentration of specific solvents varies according to the type of phenolic resin used and its molecular weight, the concentration of solvent in component A in general can be up to 60% by weight of the resin solution, being typically in the range of 10% to 40%, preferably 10 to 30%.
Une résine phénolique particulière utilisée dans la coulée en sable selon la présente invention est une résine phénolique résol, connue sous le nom de résines phénoliques résol du type éther benzylique, préparées en faisant réagir un excès d'aldéhyde avec un phénol en présence d'un catalyseur alcalin ou d'un catalyseur métallique. Sans pour autant exclure d'autres, les résines phénoliques adéquates sont de préférence sensiblement exemptes d'eau. Des exemples de résines phénoliques utilisées dans les compositions des liants en question sont bien connus dans l'art, tels que ceux décrits dans le brevet US3,485,797. Ces résines contiennent majoritairement des ponts reliant les noyaux phénoliques du polymère qui sont des ponts éther benzylique ortho- ortho. Généralement, elles sont préparées en faisant réagir un aldéhyde et un phénol dans un rapport molaire aldéhyde/phénol de 1 ,3:1 à 2,3:1 en présence d'un catalyseur d'ions métalliques, de préférence un ion métallique divalent comme le zinc, le plomb, le manganèse, le cuivre, l'étain, le magnésium, le cobalt, le calcium et le baryum. Comme connu de l'homme de l'art, les phénols utilisés pour préparer des résines phénoliques résol comprennent un ou plusieurs des phénols qui ont été employés jusqu'à présent dans la formation de résines phénoliques et qui ne sont pas substitués soit sur deux positions ortho soit sur une position ortho et sur la position para. Ces positions non substituées sont nécessaires à la réaction de polymérisation. N'importe lequel des atomes de carbone restants du cycle phénolique peut être substitué. La nature du substituant peut varier largement à condition que le substituant ne nuise pas sérieusement à la polymérisation de l'aldéhyde avec du phénol sur la position ortho et/ou para. Les phénols substitués utilisés dans la formation des résines phénoliques comprennent les alkyl-phénols substitués, les aryl-phénols substitués, les cycloalkyl phénols substitués, les phénols aryloxy substitués, et les phénols halogène substitués, ces substituants contenant de 1 à 26 atomes de carbone et de préférence de 1 à 12 atomes de carbone. Des exemples particuliers de phénols appropriés comprennent le phénol, le 2,6- xylénol, le o-crésol, le p-crésol, le 3,5-xylénol, le 3,4-xylénol, le 2,3,4-triméthyl phénol, le 3-éthyl phénol, le 3,5 diéthyl phénol, le p-butyl phénol, le 3,5-dibutyl phénol, le p-amyl phénol, le p-cyclohexyl phénol, le p-octyl phénol, le 3,5- dicyclohexyl phénol, le p-phényl phénol, le p-crotyl phénol, le 3,5-diméthoxy phénol, le 3,4,5-triméthoxy phénol, le p-éthoxy phénol, le p-butoxy phénol, le 3- méthyl-4-méthoxy phénol, et le p-phénoxy phénol. Les phénols de cycles multiples tels que le bisphénol A sont également appropriés. A particular phenolic resin used in sand casting according to the present invention is a phenolic resole resin, known as benzylic ether resole phenolic resins, prepared by reacting an excess of aldehyde with a phenol in the presence of a phenolic resin. alkaline catalyst or a metal catalyst. Without excluding others, the suitable phenolic resins are preferably substantially free of water. Examples of phenolic resins used in the compositions of the binders in question are well known in the art, such as those described in US Pat. No. 3,485,797. These resins mainly contain bridges connecting the phenolic rings of the polymer, which are ortho-ortho benzyl ether bridges. Generally, they are prepared by reacting an aldehyde and a phenol in an aldehyde / phenol molar ratio of 1.3: 1 to 2.3: 1 in the presence of a metal ion catalyst, preferably a divalent metal ion such as zinc, lead, manganese, copper, tin, magnesium, cobalt, calcium and barium. As known to those skilled in the art, the phenols used to prepare resol phenol resins include one or more of the phenols which have hitherto been employed in the formation of phenolic resins and which are unsubstituted or at two positions. ortho either on an ortho position and on the para position. These unsubstituted positions are necessary for the polymerization reaction. Any of the remaining carbon atoms of the phenolic ring may be substituted. The nature of the substituent can vary widely provided that the substituent does not seriously impair the polymerization of the aldehyde with phenol at the ortho and / or para position. The substituted phenols used in the formation of phenolic resins include substituted alkyl phenols, substituted aryl phenols, substituted cycloalkyl phenols, substituted aryloxy phenols, and substituted halogenated phenols, which substituents contain from 1 to 26 carbon atoms and preferably from 1 to 12 carbon atoms. Specific examples of suitable phenols include phenol, 2,6-xylenol, o-cresol, p-cresol, 3,5-xylenol, 3,4-xylenol, 2,3,4-trimethyl phenol , 3-ethyl phenol, 3,5-diethyl phenol, p-butyl phenol, 3,5-dibutyl phenol, p-amyl phenol, p-cyclohexyl phenol, p-octyl phenol, 3,5 dicyclohexyl phenol, p-phenyl phenol, p-crotyl phenol, 3,5-dimethoxyphenol, 3,4,5-trimethoxyphenol, p-ethoxyphenol, p-butoxyphenol, 3-methyl -4-methoxy phenol, and p-phenoxy phenol. Phenols of multiple rings such as bisphenol A are also suitable.
Les aldéhydes adéquats utilisés pour réagir avec le phénol afin d'obtenir une résine phénolique résol ont la formule R-CHO où R est un atome d'hydrogène ou un radical hydrocarboné avec 1 à 8 atomes de carbone. Les aldéhydes réagissant avec le phénol peuvent comprendre l'un des aldéhydes utilisés jusqu'à présent dans la formation de résines phénoliques tels que le formaldéhyde, l'acétaldéhyde, le propionaldéhyde, le furfuraldéhyde, et le benzaldéhyde. Suitable aldehydes used to react with phenol to obtain a phenolic resole resin have the formula R-CHO where R is a hydrogen atom or a hydrocarbon radical with 1 to 8 carbon atoms. The phenol-reactive aldehydes may include one of the aldehydes used hitherto in the formation of phenolic resins such as formaldehyde, acetaldehyde, propionaldehyde, furfuraldehyde, and benzaldehyde.
Polyisocyanate polyisocyanate
Le composant polyisocyanate du liant selon la présente invention comprend un polyisocyanate, un solvant polyisocyanate et des ingrédients optionnels. Le polyisocyanate a une fonctionnalité de deux ou plus, de préférence de 2 à 5. Il peut être aliphatique, cycloaliphatique, aromatique, ou un polyisocyanate hybride. Les polyisocyanates peuvent être également des polyisocyanates protégés, des pré-polymères de polyisocyanates et des quasi-prepolymères de polyisocyanates. Les mélanges de polyisocyanates sont également couverts par la présente invention.  The polyisocyanate component of the binder of the present invention comprises a polyisocyanate, a polyisocyanate solvent and optional ingredients. The polyisocyanate has a functionality of two or more, preferably from 2 to 5. It may be aliphatic, cycloaliphatic, aromatic, or a hybrid polyisocyanate. The polyisocyanates may also be protected polyisocyanates, polyisocyanate prepolymers and quasi-prepolymers of polyisocyanates. Polyisocyanate blends are also covered by the present invention.
Le composant polyisocyanate du liant de fonderie comprend un polyisocyanate, généralement un polyisocyanate organique, et un solvant organique, comprenant généralement des hydrocarbures aromatiques, tels que le benzène, le toluène, le xylène et/ou les alkyl-benzènes, dans des quantités allant typiquement de 0 pour cent en poids à environ 80 pour cent en poids, par rapport au poids du polyisocyanate. Des ingrédients optionnels tels que des agents de libération et des prolongeurs de vie utile peuvent également être utilisés dans le composant polyisocyanate. The polyisocyanate component of the foundry binder comprises a polyisocyanate, generally an organic polyisocyanate, and an organic solvent, generally comprising aromatic hydrocarbons, such as benzene, toluene, xylene and / or alkylbenzenes, in amounts typically ranging from from 0 percent by weight to about 80 percent by weight, based on the weight of the polyisocyanate. Optional ingredients such as release agents and life extenders may also be used in the polyisocyanate component.
Des exemples représentatifs de polyisocyanates utilisés dans la présente invention sont les polyisocyanates aliphatiques tels que le diisocyanate d'hexaméthylène, les polyisocyanates alicycliques tels que le diisocyanate de 4,4'-dicyclohexylméthane, et les polyisocyanates aromatiques tels que le 2,4 et le 2,6-toluène diisocyanate, le diisocyanate de diphénylméthane, et leurs dérivés diméthyle. D'autres exemples de polyisocyanates sont le diisocyanate de 1 ,5- naphtalène, le triisocyanate de triphénylméthane, le xylylène, et leurs dérivés méthyle, les isocyanates de polyméthylènepolyphényle, le chlorophénylène-2,4- diisocyanate, etc. Les polyisocyanates sont utilisés dans des concentrations suffisantes pour provoquer le durcissement de la résine après passage du gaz ou lorsqu'en contact avec le catalyseur de durcissement liquide. En général, le rapport entre le polyisocyanate et l'hydroxyle de la résine phénolique est de 1 ,25:1 à 1 :1 ,25. La quantité de polyisocyanate utilisée est généralement de 10 à 500 pour cent en poids, par rapport au poids de la résine phénolique. Representative examples of polyisocyanates used in the present invention are aliphatic polyisocyanates such as hexamethylene diisocyanate, alicyclic polyisocyanates such as 4,4'-dicyclohexylmethane diisocyanate, and aromatic polyisocyanates such as 2,4 and 2 , 6-toluene diisocyanate, diphenylmethane diisocyanate, and their dimethyl derivatives. Other examples of polyisocyanates are 1,5-naphthalene diisocyanate, triphenylmethane triisocyanate, xylylene, and their methyl derivatives, polymethylenepolyphenyl isocyanates, chlorophenylene-2,4-diisocyanate, and the like. The polyisocyanates are used in concentrations sufficient to cause curing of the resin after gas passage or when in contact with the liquid curing catalyst. In general, the ratio of the polyisocyanate to the hydroxyl of the phenolic resin is 1.25: 1 to 1: 1, 25. The amount of polyisocyanate used is generally from 10 to 500 percent by weight, based on the weight of the phenolic resin.
Les polyisocyanates adéquats sont utilisés en particulier sous forme liquide, pouvant être employés sous forme non diluée, tandis que polyisocyanates solides ou visqueux sont utilisés sous forme de solutions de solvants organiques. Sans exclure d'autres possibilités, les solvants adéquats pour polyisocyanate sont le AB9 et le AB10 (composés alkylbenzène contenant un substituant alkyle qui comprend respectivement 9 et 10 atomes de carbone, par exemple commercialisé sous le nom de marque Solvesso 100). Suitable polyisocyanates are used in particular in liquid form, which can be used in undiluted form, while solid or viscous polyisocyanates are used in the form of organic solvent solutions. Without excluding other possibilities, suitable solvents for polyisocyanate are AB9 and AB10 (alkylbenzene compounds containing an alkyl substituent which comprises respectively 9 and 10 carbon atoms, for example sold under the trade name Solvesso 100).
L'homme du métier sait que la différence de polarité entre le polyisocyanate et les résines phénoliques restreint le choix des solvants avec lesquels les deux composants sont compatibles. Cette compatibilité est nécessaire pour atteindre une réaction complète et le durcissement des compositions de liant de la présente invention. Les solvants polaires soit du type protique ou aprotique sont de bons solvants de la résine phénolique, mais ont une compatibilité limitée avec le polyisocyanate. Les solvants aromatiques, bien que compatibles avec le polyisocyanate, sont moins compatibles avec les résines phénoliques. Il est donc préférable d'utiliser des combinaisons de solvants et en particulier des combinaisons de solvants aromatiques et polaires. The person skilled in the art knows that the difference in polarity between the polyisocyanate and the phenolic resins restricts the choice of solvents with which the two components are compatible. This compatibility is necessary to achieve complete reaction and cure of the binder compositions of the present invention. Polar solvents of the protic or aprotic type are good solvents of the phenolic resin, but have limited compatibility with the polyisocyanate. Aromatic solvents, although compatible with polyisocyanate, are less compatible with phenolic resins. It is therefore preferable to use combinations of solvents and in particular combinations of aromatic and polar solvents.
Des exemples de solvants aromatiques des polyisocianates comprennent le benzène, le toluène, le xylène, les alkyl benzènes et leurs mélanges. Les solvants aromatiques sont de préférence un mélange de solvants aromatiques dont le point d'ébullition varie de 125° C à 250°C. En tant que co-solvants, les solvants polaires ne doivent pas être extrêmement polaires ce qui les rendraient incompatibles avec le solvant aromatique. Les solvants polaires appropriés sont généralement ceux qui sont classés dans l'art comme solvants de couplage et comprennent le furfural, l'alcool furfurylique, l'acétate de 2-éthoxyéthyle (acétate Cellosolve™), 2-butoxyéthanol (butyl Cellosolve ™), le monobutyl éther du diéthylène glycol (butyl Carbitol™), le diacétone alcool, et le 2,2,4-triméthyl-1 ,3- diol monoisobutyrate (Texanol™). Cellosolve, Carbitol, et Texanol sont des dénominations commerciales. Examples of aromatic solvents of the polyisocyanates include benzene, toluene, xylene, alkyl benzenes and mixtures thereof. The aromatic solvents are preferably a mixture of aromatic solvents whose boiling point ranges from 125 ° C to 250 ° C. As co-solvents, the polar solvents must not be extremely polar, which would make them incompatible with the aromatic solvent. Suitable polar solvents are generally those which are classified in the art as coupling solvents and include furfural, furfuryl alcohol, 2-ethoxyethyl acetate (Cellosolve ™ acetate), 2-butoxyethanol (butyl Cellosolve ™), monobutyl ether diethylene glycol (butyl Carbitol ™), diacetone alcohol, and 2,2,4-trimethyl-1,3-diol monoisobutyrate (Texanol ™). Cellosolve, Carbitol, and Texanol are trade names.
Le composant B polyisocyanate comprend éventuellement un composé hydrocarboné aromatique. The polyisocyanate component B optionally comprises an aromatic hydrocarbon compound.
Procédé Process
Un élément optionnel pour un système liant de fonderie formant un polyuréthane est une huile naturelle. L'huile naturelle est utilisée dans le composant résine phénolique, le composant isocyanate, ou dans les deux, en une quantité efficace suffisante pour améliorer la résistance à la traction des formes de fonderie à base de liants. Cette quantité est généralement comprise entre environ 1 pour cent en poids à environ 15 pour cent en poids, par rapport au poids du composant isocyanate. En général, des quantités moins importantes d'huile naturelle sont utilisés dans le composant résine phénolique, généralement d'environ 1 pour cent en poids à environ 5 pour cent en poids, par rapport au poids de la résine phénolique. Les huiles naturelles compatibles sont également adéquates. Une huile naturelle est considérée comme compatible avec l'isocyanate organique et/ou la résine phénolique si le mélange ne se sépare pas en deux phases à la température ambiante, et de préférence s'il ne se sépare pas à des températures entre 30°C à 0°C. Les huiles naturelles comprennent des huiles naturelles non modifiées ainsi que leurs diverses modifications connues, par exemple les huiles épaissies avec de la chaleur, soufflées avec de l'air ou de l'oxygène, telles que l'huile de lin soufflée et l'huile de soja soufflée. Elles sont généralement classées comme esters d'acides gras éthyléniquement insaturés. Les viscosités adéquates de l'huile naturelle varie de A à J selon l'indice de viscosité Gardner Holt. La valeur d'acidité de l'huile naturelle varie généralement de 0 à 10, telle que mesurée par le nombre de milligrammes d'hydroxyde de potassium nécessaires pour neutraliser un échantillon de 1 gramme d'huile naturelle. Comme exemples représentatifs des huiles naturelles qui sont utilisées dans le composant isocyanate l'on peut citer l'huile de lin, y compris l'huile de lin raffinée, l'huile de lin époxydée, d'huile de lin raffinée avec de l'alcali, l'huile de soja, l'huile de coton, l'huile de canola RBD (raffinée, blanchie et désodorisée), l'huile de tournesol raffinée, l'huile de tung et l'huile de ricin déshydratée. Comme huiles naturelles particulièrement utilisées on peut citer des formes plus pures d'huiles naturelles qui sont traitées pour éliminer les acides gras et autres impuretés, généralement constituées de triglycérides et de moins de 1 pour cent en poids d'impuretés telles que les acides gras et autres impuretés. Comme exemples particuliers de ces huiles naturelles pures ont peut citer les huiles de lin polymérisée (OLP) telles que l'huile de lin Suprême avec une valeur d'acidité d'environ 0,30 et une viscosité maximum de A et les huiles de soja purifiées telles que l'huile de soja raffinée ayant une valeur d'acidité inférieur à 0,1 et une viscosité de A à B. Comme il est déjà connu, cela fait augmenter les forces de traction de formes de fonderie. An optional element for a polyurethane forming binder system is a natural oil. The natural oil is used in the phenolic resin component, the isocyanate component, or both, in an effective amount sufficient to improve the tensile strength of the binder-based foundry forms. This amount is generally from about 1 percent by weight to about 15 percent by weight, based on the weight of the isocyanate component. In general, lesser amounts of natural oil are used in the phenolic resin component, generally from about 1 percent by weight to about 5 percent by weight, based on the weight of the phenolic resin. Compatible natural oils are also adequate. A natural oil is considered compatible with organic isocyanate and / or phenolic resin if the mixture does not separate in two phases at room temperature, and preferably if it does not separate at temperatures between 30 ° C at 0 ° C. Natural oils include unmodified natural oils and their various known modifications, for example heat-thickened oils blown with air or oxygen, such as flaxseed oil and oil. Soy soufflé. They are generally classified as esters of ethylenically unsaturated fatty acids. The proper viscosities of the natural oil range from A to J according to the Gardner Holt viscosity index. The acidity value of the natural oil varies typically from 0 to 10, as measured by the number of milligrams of potassium hydroxide required to neutralize a sample of 1 gram of natural oil. Representative examples of the natural oils that are used in the isocyanate component include linseed oil, including refined linseed oil, epoxidized linseed oil, linseed oil refined with alkali, soybean oil, cottonseed oil, RBD (refined, bleached and deodorized) canola oil, refined sunflower oil, tung oil and dehydrated castor oil. Particularly used natural oils include more pure forms of natural oils which are treated to remove fatty acids and other impurities, generally consisting of triglycerides and less than 1 percent by weight of impurities such as fatty acids and other impurities. Particular examples of such pure natural oils include Polymerized Linseed Oils (PLO) such as Supreme Linseed Oil with an acid value of about 0.30 and a maximum viscosity of A and soybean oils. purified oils such as refined soybean oil having an acid value of less than 0.1 and a viscosity of A to B. As is already known, this increases the tensile forces of foundry shapes.
Il faut encore ajouter que les huiles de séchage telles que décrites dans le brevet US 4,268,425 peuvent être incluses dans le liant dans l'un des solvants mentionnés ici. Ces huiles de séchage comprennent des glycérides d'acides gras contenant deux ou plus doubles liaisons. En outre, les esters d'acides gras éthyléniquement insaturés tels que les esters d'huile de pin d'alcools polyhydriques ou monohydriques peuvent être utilisés comme huile de séchage. Généralement, les huiles de séchage sont utilisées entre environ 35% et environ 50% en poids de la quantité de solvant total. Le liant peut également contenir un silane, généralement ajouté au composant de résine phénolique, par exemple tel que décrit dans le brevet US6288139. Par exemple, le silane est ajouté au composant résine phénolique dans des quantités de 0,01 à 2 pour cent en poids, par rapport au poids de la résine phénolique. It should also be added that the drying oils as described in US Pat. No. 4,268,425 can be included in the binder in one of the solvents mentioned herein. These drying oils comprise fatty acid glycerides containing two or more double bonds. In addition, ethylenically unsaturated fatty acid esters such as pine oil esters of polyhydric or monohydric alcohols can be used as the drying oil. Generally, the drying oils are used at about 35% to about 50% by weight of the total amount of solvent. The binder may also contain a silane, generally added to the phenolic resin component, for example as described in US6288139. For example, the silane is added to the phenolic resin component in amounts of 0.01 to 2 percent by weight, based on the weight of the phenolic resin.
Lors de la préparation d'une forme de fonderie ordinaire du type sable, il est de pratique courante d'utiliser l'agrégat avec une granulométrie assez grande pour fournir une porosité suffisante à la forme de fonderie afin de permettre l'évacuation des matières volatiles de la forme au cours de l'opération de coulée. Le terme «formes de fonderie ordinaires du type sable », tel qu'il est utilisé ici, se réfère à des formes de fonderie qui ont une porosité suffisante pour permettre l'évacuation des matières volatiles au cours de l'opération de coulée. En général, au moins environ 80% en poids des agrégats utilisés pour des formes de fonderie ont une granulométrie moyenne non inférieure à environ 50 et à environ 50 mesh (Tyler Screen Mesh). Un agrégat adéquat utilisé pour des formes de fonderie ordinaire est la silice dans laquelle environ 70% pourcent en poids du sable est constitué de silice. D'autres matériaux appropriés comprennent du zircon, l'olivine, l'aluminosilicate, le sable, le sable de chromite, etc. Bien que les meilleurs résultats soient souvent obtenus lorsque l'agrégat utilisé est sec, il peut contenir de petites quantités d'humidité. In the preparation of an ordinary sand-type foundry form, it is common practice to use the aggregate with a particle size large enough to provide sufficient porosity to the foundry form to permit evacuation of volatile materials. of the form during the casting operation. The term "ordinary sand-type foundry shapes" as used herein refers to foundry shapes that have sufficient porosity to permit evacuation of volatiles during the casting operation. In general, at least about 80% by weight of the aggregates used for foundry shapes have an average particle size of not less than about 50 and about 50 mesh (Tyler Screen Mesh). A suitable aggregate used for ordinary foundry shapes is silica in which about 70% by weight of the sand is silica. Other suitable materials include zircon, olivine, aluminosilicate, sand, chromite sand, and the like. Although the best results are often obtained when the aggregate used is dry, it may contain small amounts of moisture.
Dans les compositions de moulage, l'agrégat constitue le principal constituant, le liant étant présent en une quantité relativement faible. Dans les applications de fonderie du type sable, la quantité de liant ne dépasse pas généralement environ 10% en poids et se situe fréquemment dans la gamme de 0,5 à 7% en poids par rapport au poids de l'agrégat, en particulier 1 ,0 à 1 ,8%. In the molding compositions, the aggregate constitutes the main constituent, the binder being present in a relatively small amount. In sand-type foundry applications, the amount of binder does not generally exceed about 10% by weight and is frequently in the range of 0.5 to 7% by weight based on the weight of the aggregate, particularly 0 to 1, 8%.
Les compositions de liant sont de préférence mises à disposition comme un système à double paquet avec le composant résine phénolique dans un paquet et le composant polyisocyanate dans l'autre. Habituellement, le composant résine phénolique est mélangé avec l'agrégat, puis le composant polyisocyanate est ajouté. Les méthodes de répartition du liant sur les particules d'agrégat sont bien connues de l'homme du métier. The binder compositions are preferably provided as a double package system with the phenolic resin component in one package and the polyisocyanate component in the other. Usually, the phenolic resin component is mixed with the aggregate, and then the polyisocyanate component is added. Binder distribution methods on aggregate particles are well known to those skilled in the art.
Un autre aspect de la présente invention concerne les procédés pour obtenir des formes par coulée en sable, utilisant le nouveau système de liant, qui est moulé dans la forme désirée, telle qu'un un moule ou un noyau, et durcis. Le durcissement par le procédé en boîte froide est réalisée en passant une aminé volatile tertiaire, par exemple la triéthylamine, le 1-diméthylamino-2-propanol (DMA-2P), la monoéthanolamine ou la diméthylaminopropylamine (DMAPA), à travers la forme dans le moule tel que décrit dans le brevet US 3,409,579. Le durcissement par le procédé sans cuisson est effectué en mélangeant un catalyseur de durcissement aminé liquide dans le système liant de fonderie, qui est ensuite mis en forme, et mis à durcir. Conformément au système liant selon l'invention, on entend par « quantité catalytiquement efficace d'un catalyseur de durcissement » une concentration du catalyseur préférentiellement comprise entre 0,2 et 5,0 pour cent en poids de la résine phénolique. Another aspect of the present invention relates to methods for obtaining sand casting forms, using the novel binder system, which is molded into the desired shape, such as a mold or core, and cured. Curing by the cold box process is carried out by passing a tertiary volatile amine, for example triethylamine, 1-dimethylamino-2-propanol (DMA-2P), monoethanolamine or dimethylaminopropylamine (DMAPA), through the form in the mold as described in US Patent 3,409,579. Curing by the non-firing process is performed by mixing a liquid amine curing catalyst in the foundry binder system, which is then shaped, and set to cure. According to the binder system according to the invention, the term "catalytically effective amount of a curing catalyst" a concentration of the catalyst preferably between 0.2 and 5.0 percent by weight of the phenolic resin.
Les aminés liquides catalyseurs de durcissement utiles ont une valeur pKb généralement de l'ordre de 7 à 11. Comme exemples particuliers de ces aminés on peut citer les 4-alkyl-pyridines, l'isoquinoléine, les arylpyridines, le 1- méthylbenzimidazole, et la 1 ,4-thiazine. Une aminé liquide tertiaire particulièrement utilisé comme catalyseur est une aminé tertiaire aliphatique telle que la tris (3-diméthylamino) propylamine). En général, la concentration du catalyseur d'amine liquide varie de 0,2 à 5,0 pour cent en poids de la résine phénolique, en particulier de 1 ,0 à 4,0 pour cent en poids, plus particulièrement de 2,0 à 3,5 pour cent en poids par rapport au poids du polyol polyéther. Les catalyseurs tels que la triéthylamine ou la diméthyléthylamine sont utilisés dans une gamme variant 0,05 à 0,15 pour cent en poids par rapport au poids du liant.  The useful liquid curing catalyst amines have a pKb value generally of the order of 7 to 11. Particular examples of these amines include 4-alkylpyridines, isoquinoline, arylpyridines, 1-methylbenzimidazole, and 1,4-thiazine. A tertiary liquid amine particularly used as catalyst is an aliphatic tertiary amine such as tris (3-dimethylamino) propylamine). In general, the concentration of the liquid amine catalyst ranges from 0.2 to 5.0 percent by weight of the phenolic resin, in particular from 1.0 to 4.0 percent by weight, more preferably 2.0. to 3.5 percent by weight based on the weight of the polyether polyol. Catalysts such as triethylamine or dimethylethylamine are used in a range of 0.05 to 0.15 percent by weight based on the weight of the binder.
Un langage spécifique est utilisé dans la description de manière à faciliter la compréhension du principe de l'invention. Il doit néanmoins être compris qu'aucune limitation de la portée de l'invention n'est envisagée par l'utilisation de ce langage spécifique. Des modifications, améliorations et perfectionnements peuvent notamment être envisagés par une personne au fait du domaine technique concerné sur la base de ses propres connaissances générales. A specific language is used in the description so as to facilitate understanding of the principle of the invention. It must nevertheless be understood that no limitation of the scope of the invention is envisaged by the use of this specific language. In particular, modifications, improvements and improvements may be considered by a person familiar with the technical field concerned on the basis of his own general knowledge.
Le terme et/ou inclut les significations et, ou, ainsi que toutes les autres combinaisons possibles des éléments connectés à ce terme. The term and / or includes the meanings and, or, as well as all other possible combinations of elements connected to this term.
D'autres détails ou avantages de l'invention apparaîtront plus clairement au vu des exemples donnés ci-dessous uniquement à titre indicatif. Other details or advantages of the invention will emerge more clearly in the light of the examples given below solely for information purposes.
PARTIE EXPERIMENTALE EXPERIMENTAL PART
L'exemple qui suit représente un mode de réalisation particulier de l'invention, sans aucun caractère limitatif, tel que décrit dans le jeu de revendications présenté plus loin.  The following example represents a particular embodiment of the invention, without any limiting character, as described in the set of claims presented below.
Le pouvoir de solubilisation des solvants testés dans cet exemple a été déterminé par simulation au moyen du logiciel Solsys ® (Rhodia). Il est basé sur la théorie des paramètres de solubilité et le système tridimensionnel de Hansen. Comme il est en effet connu de l'homme du métier, les paramètres d'énergie de cohésion les plus largement utilisés pour la caractérisation des solvants sont ceux développés par Hansen (par exemple dans l'oeuvre "Hansen Solubility Parameters: A user's handbook" Hansen, Charles Second Edition 2007 Boca Raton, FL, États-Unis. CRC Press). Il y a trois chiffres qui, ensemble, sont appelés HSP. Ils décrivent entièrement la manière dont un solvant se comporte par rapport à ce qui est dissous si leurs HSP sont connus ou peuvent être estimés: The solubilization power of the solvents tested in this example was determined by simulation using Solsys ® software (Rhodia). It is based on Hansen's solubility parameter theory and three-dimensional system. As it is in fact known to those skilled in the art, the most widely used cohesion energy parameters for the characterization of solvents are those developed by Hansen (for example in the work "Hansen Solubility Parameters: A user's handbook". Hansen, Charles Second Edition 2007 Boca Raton, FL, USA (CRC Press). There are three numbers that together are called HSPs. They fully describe how a solvent behaves relative to what is dissolved if their HSPs are known or can be estimated:
ôD- L'énergie de la dispersion des liens entre les molécules  ôD- The energy of the dispersion of the links between the molecules
δΡ- L'énergie de la force dipolaire intermoléculaire entre molécules  δΡ- The energy of the intermolecular dipole force between molecules
- δΗ- L'énergie de liaisons hydrogène entre molécules. - δΗ- The energy of hydrogen bonds between molecules.
Hansen a démontré que les substances sont caractérisées par ôD, δΡ et δΗ. La technique de détermination des paramètres de solubilité D, P, H d'une substance, à savoir d'une résine phénolique dans cet exemple, consiste à tester la solubilité de ladite substance dans une série de solvants purs qui appartiennent à différents groupes chimiques (par exemple, hydrocarbures, cétones, esters, alcools et glycols). L'évaluation est faite en considérant les solvants qui solubilisent complètement, partiellement ou ne solubilisent pas la substance à solubiliser. Le Logiciel Solsys® permet de déterminer le volume de solubilité de la substance et en conséquence il permet de déterminer le meilleur solvant pour dissoudre la substance. Le volume de solubilité est représenté par une sphère (système tridimensionnel) dont le centre correspond à une « distance normalisée » égale à 0 et traduit le maximum de solubilité. L'ensemble des points situés sur la surface de la sphère correspondent à une « distance normalisée » égale à 1 et traduisent la limite de solubilité. La sphère est représentée sur un graphique dont les axes correspondent aux ôD, δΡ et δΗ. La solubilité de la résine dans le solvant sera d'autant meilleure que le volume de solubilité sera proche du centre (distance normalisée égale à 0). Au-delà de la surface de la sphère (distance normalisée égale à 1), la résine n'est plus soluble dans le solvant. Les valeurs de «distance normalisée» sont utilisées pour évaluer le pouvoir de solubilisation d'une substance, à savoir de la résine phénolique dans le cas d'espèce, dans un solvant. Plus la valeur de la distance normalisée est proche de zéro, plus la résine est soluble dans le solvant. Le tableau I ci-dessous montre les valeurs des paramètres de solubilité d'un mélange commercial d'esters de diméthyle, par rapport à la triacétine de pureté supérieure à 99,5% et la triacétine industrielle. Les distances normalisées ont été obtenues pour une résine phénolique résol. TABLEAU I Hansen demonstrated that the substances are characterized by δD, δΡ and δΗ. The technique for determining the solubility parameters D, P, H of a substance, namely a phenolic resin in this example, consists in testing the solubility of said substance in a series of pure solvents which belong to different chemical groups ( for example, hydrocarbons, ketones, esters, alcohols and glycols). The evaluation is made by considering the solvents which completely solubilize, partially or do not solubilize the substance to be solubilized. The Solsys® Software is used to determine the solubility volume of the substance and as a result it determines the best solvent for dissolving the substance. The volume of solubility is represented by a sphere (three-dimensional system) whose center corresponds to a "standardized distance" equal to 0 and represents the maximum of solubility. The set of points on the surface of the sphere correspond to a "standardized distance" equal to 1 and reflect the limit of solubility. The sphere is represented on a graph whose axes correspond to δD, δΡ and δΗ. The solubility of the resin in the solvent will be all the better that the volume of solubility will be close to the center (normalized distance equal to 0). Beyond the surface of the sphere (normalized distance equal to 1), the resin is no longer soluble in the solvent. "Standardized distance" values are used to evaluate the solubilizing power of a substance, i.e. phenolic resin in this case, in a solvent. The more the value of the normalized distance is close to zero, the more the resin is soluble in the solvent. Table I below shows the solubility parameter values of a commercial mixture of dimethyl esters, compared with triacetin with purity higher than 99.5% and industrial triacetin. Standardized distances were obtained for a phenolic resole resin. TABLE I
Figure imgf000018_0002
Figure imgf000018_0002
(*) 62% en poids de glutarate de diméthyle, 23% en poids de succinate de diméthyle, 15% en poids d'adipate de diméthyle. ( * ) 62% by weight of dimethyl glutarate, 23% by weight of dimethyl succinate, 15% by weight of dimethyl adipate.
(**) Environ 86% en poids de triacétine, 10% en poids de diacétine, 4% en poids de monoacétine. ( ** ) About 86% by weight of triacetin, 10% by weight of diacetin, 4% by weight of monoacetin.
Les formules générales des solvants RPDE, triacétine et triacétine industrielle sont données ci-dessous. The general formulas of the solvents RPDE, triacetin and triacetin are given below.
Figure imgf000018_0001
Figure imgf000018_0001
Comme on le voit, les valeurs des paramètres de solubilité pour le mélange de solvants esters de diméthyle commerciaux sont similaires à ceux qui sont obtenus pour la triacétine. Cela signifie que les solvants sont partiellement ou totalement interchangeables, pour la plupart des applications, en particulier en mélange, qui dépend des conditions commerciales. Les distances normalisées sont aussi très proches, notamment pour la solubilité dans le RPDE et la triacétine de pureté supérieure à 99,5%. As can be seen, the solubility parameter values for the commercial dimethyl ester solvent mixture are similar to those obtained for triacetin. This means that the solvents are partially or totally interchangeable for most applications, especially in blending, which depends on commercial conditions. Standard distances are also very close, especially for solubility in RPDE and triacetin with purity higher than 99.5%.
De plus, il a été démontré que la triacétine Industrielle présente un meilleur pouvoir de solubilité. En effet, la distance normalisée obtenue est inférieure à celle obtenue avec le RPDE et la triacétine seule, ce qui permet de réduire la quantité de solvant pour dissoudre la résine phénolique, par rapport au Rhodiasolv RPDE et la triacétine, sans perte de performance. La présence des groupements hydroxyles (-OH) dans la monoacétine et la diacétine justifie l'augmentation de la polarité (valeur du δΡ - Tableau I), et du pouvoir de solubilisation de la triacétine industrielle. En respectant la plage de concentration de triacétine dans la triacétine industrielle (de 80% à 95% en poids), aucune réaction indésirable n'est observée entre les -OH libres et le polyisocyanate. In addition, it has been shown that industrial triacetin has a better solubility. Indeed, the normalized distance obtained is lower than that obtained with RPDE and triacetin alone, which makes it possible to reduce the amount of solvent to dissolve the phenolic resin, compared to Rhodiasolv RPDE and triacetin, without loss of performance. The presence of hydroxyl groups (-OH) in monoacetin and diacetin justifies the increase in polarity (δΡ value - Table I), and the solubilization capacity of industrial triacetin. By respecting the concentration range of triacetin in industrial triacetin (from 80% to 95% by weight), no undesirable reaction is observed between the free -OHs and the polyisocyanate.
L'homme du métier, avec les informations fournies ici, est en mesure de reproduire l'invention de différentes manières, mais avec la même fonction pour atteindre des résultats similaires. Ces modes de réalisation équivalents sont également couverts par les revendications ci-dessous. Those skilled in the art, with the information provided herein, are able to reproduce the invention in different ways, but with the same function to achieve similar results. These equivalent embodiments are also covered by the claims below.

Claims

REVENDICATIONS
1. Système liant de fonderie formant un polyuréthane durcissable avec une quantité catalytiquement efficace d'un catalyseur de durcissement, comprenant au moins : A curable binder system forming a curable polyurethane with a catalytically effective amount of a curing catalyst, comprising at least:
A. un composant résine phénolique comprenant au moins:  A. a phenolic resin component comprising at least:
(1) une résine phénolique; et  (1) a phenolic resin; and
(2) un solvant comprenant au moins de la triacétine ; et  (2) a solvent comprising at least triacetin; and
B. un composant polyisocyanate.  B. a polyisocyanate component.
2. Système liant selon la revendication 1 dans lequel la triacétine est obtenu à partir d'un procédé utilisant de la glycérine brute. The binder system of claim 1 wherein the triacetin is obtained from a process using crude glycerin.
3. Système liant selon la revendication 1 dans lequel le solvant est un mélange comprenant au moins 80 % en poids de triacétine. 3. Binder system according to claim 1 wherein the solvent is a mixture comprising at least 80% by weight of triacetin.
4. Système liant selon la revendication 1 dans lequel le solvant est un mélange comprenant 80 à 95% en poids de triacétine, 5 à 15% en poids de diacétine et moins de 5% en poids de monoacétine, par rapport au poids total du mélange. 4. Binder system according to claim 1 wherein the solvent is a mixture comprising 80 to 95% by weight of triacetin, 5 to 15% by weight of diacetin and less than 5% by weight of monoacetin, relative to the total weight of the mixture .
5. Système liant selon la revendication 1 dans lequel ledit composant A comprend en outre un solvant qui est un mélange d'esters de diméthyle, notamment l'adipate de diméthyle, le glutarate de diméthyle et le succinate de diméthyle. The binder system of claim 1 wherein said component A further comprises a solvent which is a mixture of dimethyl esters, especially dimethyl adipate, dimethyl glutarate and dimethyl succinate.
6. Système liant selon la revendication 5, dans lequel le rapport du solvant comprenant au moins de la triacétine et dudit mélange d'esters de diméthyle varie de 1 :20 à 20 :1. The binder system of claim 5, wherein the ratio of the solvent comprising at least triacetin and said dimethyl ester mixture ranges from 1:20 to 20: 1.
7. Système liant selon la revendication 1 dans lequel ledit composant A comprend en outre un ou plusieurs solvants hydrocarbonés aromatiques. The binder system of claim 1 wherein said component A further comprises one or more aromatic hydrocarbon solvents.
8. Système liant selon la revendication 1 dans lequel le solvant comprenant au moins la triacétine représente de 10 à 30% en poids du poids de du composant A. 8. Binder system according to claim 1 wherein the solvent comprising at least triacetin represents from 10 to 30% by weight of the weight of the component A.
9. Système liant selon la revendication 1 dans lequel ladite résine phénolique est une résine phénolique résol. The binder system of claim 1 wherein said phenolic resin is a phenolic resole resin.
10. Système liant selon la revendication 1 dans lequel ledit composant polyisocyanate comprend un polyisocyanate et un solvant de polyisocyanate. The binder system of claim 1 wherein said polyisocyanate component comprises a polyisocyanate and a polyisocyanate solvent.
11. Système liant selon la revendication 10 dans lequel ledit solvant de polyisocyanate est un mélange d'hydrocarbures aromatiques, notamment choisis parmi le benzène, le toluène, le xylène, les alkyl-benzènes et leurs mélanges. 11. Binder system according to claim 10 wherein said polyisocyanate solvent is a mixture of aromatic hydrocarbons, especially selected from benzene, toluene, xylene, alkyl-benzenes and mixtures thereof.
12. Mélange de fonderie comprenant un système liant formant un polyuréthane tel que décrits dans l'une quelconque des revendications 1 à 11 , et un agrégat. 12. A foundry mix comprising a polyurethane-forming binder system as described in any one of claims 1 to 11, and an aggregate.
13. Mélange selon la revendication 2, dans lequel ledit agrégat est le sable. 13. Mixture according to claim 2, wherein said aggregate is sand.
14. Procédé visant à préparer une forme de fonderie par le procédé en boîte froide dans laquelle le liant est tel que décrit dans l'une quelconque des revendications 1 à 11 , et le catalyseur de durcissement est une aminé gazeuse. 14. A process for preparing a foundry form by the cold box process in which the binder is as described in any one of claims 1 to 11, and the curing catalyst is a gaseous amine.
15. Procédé visant à préparer une forme de fonderie par le procédé sans cuisson dans laquelle le liant est tel que décrit dans l'une quelconque des revendications 1 à 11 , et le catalyseur de durcissement est une aminé liquide. A process for preparing a foundry form by the non-firing process wherein the binder is as described in any one of claims 1 to 11, and the curing catalyst is a liquid amine.
16. Forme de fonderie préparée par le procédé selon l'une quelconque des revendications 14 ou 15. 16. Foundry form prepared by the process according to any one of claims 14 or 15.
17. Utilisation d'un mélange comprenant au moins de la triacétine comme solvant utile pour les résines phénoliques dans les systèmes liants de fonderie formant du polyuréthane, seuls ou en mélange avec d'autres solvants. 17. Use of a mixture comprising at least triacetin as a solvent useful for phenolic resins in polyurethane-forming foundry binder systems, alone or in admixture with other solvents.
PCT/IB2012/000539 2011-03-22 2012-03-20 Foundry binder systems WO2012127299A1 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
US14/001,241 US20140018468A1 (en) 2011-03-22 2012-03-20 Foundry binder systems
BR112013023910A BR112013023910A2 (en) 2011-03-22 2012-03-20 casting binder system, casting mix, processes for preparing a casting form, casting form and use of a mixture
CN2012800142919A CN103442824A (en) 2011-03-22 2012-03-20 Foundry binder systems
EP12718327.5A EP2688698A1 (en) 2011-03-22 2012-03-20 Foundry binder systems

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR1152347A FR2972946B1 (en) 2011-03-22 2011-03-22 FOUNDRY BONDING SYSTEMS
FR1152347 2011-03-22

Publications (1)

Publication Number Publication Date
WO2012127299A1 true WO2012127299A1 (en) 2012-09-27

Family

ID=44169081

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IB2012/000539 WO2012127299A1 (en) 2011-03-22 2012-03-20 Foundry binder systems

Country Status (7)

Country Link
US (1) US20140018468A1 (en)
EP (1) EP2688698A1 (en)
CN (1) CN103442824A (en)
AR (1) AR085479A1 (en)
BR (1) BR112013023910A2 (en)
FR (1) FR2972946B1 (en)
WO (1) WO2012127299A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021237681A1 (en) * 2020-05-29 2021-12-02 Rhodia Poliamida E Especialidades Sa Chemoenzymatic degradation of epoxy resins

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103897124B (en) * 2014-03-25 2016-05-11 宁夏共享集团有限责任公司 A kind of production method of casting with cold box resin
CN113351823B (en) * 2021-05-26 2023-04-28 共享新材料(山东)有限公司 Sand mould reinforcing liquid and preparation and use methods thereof

Citations (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US55168A (en) 1866-05-29 Improvement in heating and ventilating railroad-cars
US3409579A (en) 1966-08-01 1968-11-05 Ashland Oil Inc Foundry binder composition comprising benzylic ether resin, polyisocyanate, and tertiary amine
US3485797A (en) 1966-03-14 1969-12-23 Ashland Oil Inc Phenolic resins containing benzylic ether linkages and unsubstituted para positions
US3920460A (en) 1973-05-16 1975-11-18 Frank J Boston Process for producing a bonded particulate material
US4268425A (en) 1979-05-14 1981-05-19 Ashland Oil, Inc. Phenolic resin-polyisocyanate binder systems containing a drying oil and use thereof
US4468359A (en) 1982-11-09 1984-08-28 Borden (Uk) Limited Foundry moulds and cores
CS258845B1 (en) 1987-06-25 1988-09-16 Petr Jelinek Method of foundry sand and core mixtures regeneration
US4852629A (en) 1986-08-25 1989-08-01 Ashland Oil, Inc. Cold-box process for forming foundry shapes which utilizes certain carboxylic acids as bench life extenders
WO1989007626A1 (en) 1988-02-16 1989-08-24 Ashland Oil, Inc. Low solids polyurethane-forming foundry binders for cold-box process
US4862948A (en) * 1988-02-24 1989-09-05 Borden, Inc. Phenolic resin adhesive pastes, assemblies prepared therefrom, and processes for preparing cast metal articles using these pastes
JPH0318530B2 (en) 1986-08-01 1991-03-12 Kobe Rikagaku Kogyo Kk
WO1991009908A1 (en) 1989-12-21 1991-07-11 Ashland Oil, Inc. Polyurethane-forming foundry binders and their use
US5043412A (en) 1988-06-23 1991-08-27 Borden, Inc. Ambient temperature curing, high carbon contributing compositions
US5169880A (en) 1990-04-03 1992-12-08 Kao Corporation Process for making foundry sand mold
US5602192A (en) 1990-07-05 1997-02-11 Kao Corporation Process for producing sand mold
US6136888A (en) * 1995-11-01 2000-10-24 Huttenes-Albertus Chemische Werke Gmbh Binder system on the basis of polyurethane for molding material mixtures for use in the production of casting molds and cores
EP1057554A2 (en) * 1999-06-01 2000-12-06 Hüttenes-Albertus Chemische-Werke GmbH Binder for producing foundry mould and core compositions
EP1074568A2 (en) 1999-08-02 2001-02-07 Cavenaghi SPA Foundry binder systems
US6288139B1 (en) 1998-09-24 2001-09-11 Ashland Inc. Foundry binder system containing an ortho ester and their use
EP1809456A1 (en) 2004-10-13 2007-07-25 E.I.Du pont de nemours and company Anti-stick coating for surfaces
JP4198531B2 (en) 2003-05-30 2008-12-17 旭有機材工業株式会社 Curable composition and foundry sand composition and mold obtained using the same
EP2272818A1 (en) 2009-07-01 2011-01-12 Rhodia Poliamida E Especialidades Ltda Process to obtain a mixture of lower carboxylic mono, di and triesters from raw glycerin

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1062683A (en) * 1992-02-12 1992-07-15 周济 Casting chaplet box is with adhesive and preparation method
CN1155255A (en) * 1994-06-14 1997-07-23 K·R·库泼 Foundry resins
DE102005024246A1 (en) * 2005-05-27 2006-11-30 Degussa Ag Copolymers, a process for their preparation and the use as binders

Patent Citations (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US55168A (en) 1866-05-29 Improvement in heating and ventilating railroad-cars
US3485797A (en) 1966-03-14 1969-12-23 Ashland Oil Inc Phenolic resins containing benzylic ether linkages and unsubstituted para positions
US3409579A (en) 1966-08-01 1968-11-05 Ashland Oil Inc Foundry binder composition comprising benzylic ether resin, polyisocyanate, and tertiary amine
US3920460A (en) 1973-05-16 1975-11-18 Frank J Boston Process for producing a bonded particulate material
US4268425A (en) 1979-05-14 1981-05-19 Ashland Oil, Inc. Phenolic resin-polyisocyanate binder systems containing a drying oil and use thereof
US4468359A (en) 1982-11-09 1984-08-28 Borden (Uk) Limited Foundry moulds and cores
JPH0318530B2 (en) 1986-08-01 1991-03-12 Kobe Rikagaku Kogyo Kk
US4852629A (en) 1986-08-25 1989-08-01 Ashland Oil, Inc. Cold-box process for forming foundry shapes which utilizes certain carboxylic acids as bench life extenders
CS258845B1 (en) 1987-06-25 1988-09-16 Petr Jelinek Method of foundry sand and core mixtures regeneration
WO1989007626A1 (en) 1988-02-16 1989-08-24 Ashland Oil, Inc. Low solids polyurethane-forming foundry binders for cold-box process
US4862948A (en) * 1988-02-24 1989-09-05 Borden, Inc. Phenolic resin adhesive pastes, assemblies prepared therefrom, and processes for preparing cast metal articles using these pastes
US5043412A (en) 1988-06-23 1991-08-27 Borden, Inc. Ambient temperature curing, high carbon contributing compositions
WO1991009908A1 (en) 1989-12-21 1991-07-11 Ashland Oil, Inc. Polyurethane-forming foundry binders and their use
US5169880A (en) 1990-04-03 1992-12-08 Kao Corporation Process for making foundry sand mold
US5602192A (en) 1990-07-05 1997-02-11 Kao Corporation Process for producing sand mold
US6136888A (en) * 1995-11-01 2000-10-24 Huttenes-Albertus Chemische Werke Gmbh Binder system on the basis of polyurethane for molding material mixtures for use in the production of casting molds and cores
US6288139B1 (en) 1998-09-24 2001-09-11 Ashland Inc. Foundry binder system containing an ortho ester and their use
EP1057554A2 (en) * 1999-06-01 2000-12-06 Hüttenes-Albertus Chemische-Werke GmbH Binder for producing foundry mould and core compositions
EP1074568A2 (en) 1999-08-02 2001-02-07 Cavenaghi SPA Foundry binder systems
JP4198531B2 (en) 2003-05-30 2008-12-17 旭有機材工業株式会社 Curable composition and foundry sand composition and mold obtained using the same
EP1809456A1 (en) 2004-10-13 2007-07-25 E.I.Du pont de nemours and company Anti-stick coating for surfaces
EP2272818A1 (en) 2009-07-01 2011-01-12 Rhodia Poliamida E Especialidades Ltda Process to obtain a mixture of lower carboxylic mono, di and triesters from raw glycerin

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
HANSEN, CHARLES: "Hansen Solubility Parameters: A user's handbook Second Edition", 2007, CRC PRESS

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021237681A1 (en) * 2020-05-29 2021-12-02 Rhodia Poliamida E Especialidades Sa Chemoenzymatic degradation of epoxy resins

Also Published As

Publication number Publication date
FR2972946B1 (en) 2013-03-29
EP2688698A1 (en) 2014-01-29
FR2972946A1 (en) 2012-09-28
US20140018468A1 (en) 2014-01-16
AR085479A1 (en) 2013-10-02
CN103442824A (en) 2013-12-11
BR112013023910A2 (en) 2016-12-13

Similar Documents

Publication Publication Date Title
JP3647998B2 (en) Polyurethane-based binders for molding material mixtures in the production of casting molds and core molds
EP2956513B1 (en) Solvent system and compositions therewith
JP6887595B2 (en) Polyurethane cold box and / or phenolic resin compositions used in the no-bake method and corresponding two-component binder systems, uses, and methods.
CH647250A5 (en) BINDERS AND ITS USE FOR THE PRODUCTION OF FOUNDRY SHAPES AND CORES AND MOLDS.
WO2012127299A1 (en) Foundry binder systems
EP2249982B1 (en) Use of branched alkane diol carboxylic acid diesters in polyurethane-based foundry binders
WO2000025957A1 (en) Binder system for producing polyurethane-based cores and melting moulds
JP2013173937A (en) Use of amine blends for foundry shaped core and casting metal
FR2845390A1 (en) PIGMENT COMPOSITIONS OF METAL ALUMINUM PARTICLES
US6288139B1 (en) Foundry binder system containing an ortho ester and their use
FR2491363A1 (en) BINDER COMPOSITION FOR SAND FOUNDRY MOLDS AND CORES
EP3558559B1 (en) Component system for producing cores and molds
JP2018518370A (en) Three component polyurethane binder system
WO1995005409A1 (en) Materials for producing foundry cores and moulds
JP6798083B2 (en) Binder system suitable for reducing metal mold reaction
DE102020118314A1 (en) Means for reducing sand adhesions
JPS60158944A (en) Composition for curable casting mold
BE677474A (en)

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 12718327

Country of ref document: EP

Kind code of ref document: A1

WWE Wipo information: entry into national phase

Ref document number: 2012718327

Country of ref document: EP

NENP Non-entry into the national phase

Ref country code: DE

WWE Wipo information: entry into national phase

Ref document number: 14001241

Country of ref document: US

REG Reference to national code

Ref country code: BR

Ref legal event code: B01A

Ref document number: 112013023910

Country of ref document: BR

ENP Entry into the national phase

Ref document number: 112013023910

Country of ref document: BR

Kind code of ref document: A2

Effective date: 20130918