EP0192252A1 - Method for improving the holdout of printing inks, lacquers and coating compositions on sheetlike structures made of fibers and for improving the deinking of the fibers composition for implementing the method, and sheetlike structures produced therewith - Google Patents

Abstract

The process according to the invention for improving the holdout of printing inks, lacquers and coating compositions containing organic solvents on fabrics made of fibers, in particular on paper and for improving the de-inking of the fibers, consists in that an organophilic complex of (a) a water-insoluble hydrated cation-exchangeable film-forming smectic layered silicate with an ion exchange capacity of at least 50 meq / 100 g and (b) an attached organic residue derived from an onium compound into the fiber mass or into the surface of the fiber structure, the organophilic complex by reaction with the organic solvent Barrier forms.

Description

The invention relates to a method for improving the holdout of printing inks, lacquers and coating compositions, on fabrics made of fibers, in particular on paper, and for improving the de-inking of the fibers.

It is known, for example from EU-PS 0 017 793, to improve the printability of paper by the fact that hydratable film-forming, colloidal clays, e.g. Bentonite, attapulgite or sepiolite can be incorporated into the paper pulp. Macromolecules of polyglycol with a molecular weight of 5,000 to 100,000 can also be attached to these colloidal clays. The improvement in the satinability and printability caused by these measures consists in an improved "color balance", i.e. the printing ink does not blow away as quickly for a short time (between its application to the paper and its drying), but the same color contours as are applied to the paper are also present on the finished printed and dried paper. If the "color level" is poor, on the other hand, the printing ink strikes the paper and diffuses, i.e. it spreads out in the paper, which leads to a non-uniform and fuzzy and mostly matt print image. The main reason for the improved color level is seen in the fact that the hydratable, film-forming, colloidal clays contain a considerable proportion of bound water. This water cannot escape at the drying temperatures normally used in a paper machine and, since it is immiscible with the solvent of the gravure printing ink, causes a kind of rejection of the printing ink.

When using a mixture of colloidal clays and polyglycols, it is assumed that the polyglycols, like the water, are deposited between the colloidal clays, that is, they do not form any reaction products, and because of their waxy nature, they improve the satinability after drying. There is no reaction with the organic solvent in which the ink is dissolved or dispersed.

The present invention aims at an improvement of the _H oldouts organic solvent systems, such as printing inks, paints and coating compositions, in other ways. The problem of holdouts is particularly pronounced in gravure printing processes, since gravure inks have to have a much lower viscosity compared to other inks (for high pressure or offset printing). The invention is therefore primarily applicable in the field of gravure printing, which is why the explanations below relate primarily to this field. Furthermore, the fabrics made of fibers to be printed according to the invention are primarily those made of paper, although nonwovens or textiles (for example silk, cotton and linen fabrics) can also be printed using the present invention.

• 1. das hochgefüllte, satinierte, meist holzhaltige _Tiefdruckpapier in Flächengewichten zwischen 40 bis etwa 80 g/m² und
• 2. das gestrichene, holzhaltige oder holzfreie hochsatinierte Tiefdruckpapier in Flächengewichten zwischen 45 und etwa 135 g/_m ².

Gravure printing is one of the most widespread types of printing for all types of bulk printing. Two types of paper are used, namely

• 1. The highly filled, satin, mostly wood-containing _T iefdruckpapier in basis weights between 40 to about 80 g / m ² and
• 2. The coated, wood-containing or wood-free, highly satinized gravure printing paper in basis weights between 45 and about 135 g / _m ² .

For economic and postal reasons, there has been a tendency for years to reduce the basis weights of such papers. There are limits to this wish, especially with coated gravure paper, but also with natural gravure paper.

In order to have a good level of gravure ink on the paper surface, the line of the coated varieties must have a minimum thickness of about 6.5 to 7 g / m ² and page; with double-sided coated low

Printing paper with a total weight of 50 g / m ² results in a base paper of approximately 36 g / m2. From today's perspective, this is a lower limit, since it is only the fibers of the coating base paper that contribute to the physical strength values of the printing paper. On the other hand, the uncoated rotogravure papers are not equivalent to the coated rotogravure papers neither in the whiteness nor in the gloss of the print products that can be produced. In particular, the consumption of gravure printing ink is about two and a half to three times that of the coated paper, because the porosity and thus the absorbency of the gravure printing paper is much greater. As a result, the shining through of the print on the back (the so-called print opacity) is a particular problem with these papers when the basis weight is further reduced.

The use of hydratable film-forming colloidal clays described in the above-mentioned EU-PS 0 017 793 succeeded to a certain extent in closing the surface of the uncoated gravure printing paper somewhat and in improving the printability. The rotogravure papers treated in this way, however, are not yet approximately comparable in color with the coated rotogravure papers. However, the use of the hydrated film-forming clays described in EU-PS 0 017 793 in coating formulations or as a surface coating is impossible for rheological reasons.

The invention has for its object to treat the surface of fabrics made of fibers, in particular paper, so that the coating composition or printing ink or the lacquer, in particular a low-viscosity gravure printing ink, dispersed or dissolved in an organic solvent, as little as possible into the Paper strikes.

_The less they penetrate, the lower the consumption and the more beautiful the gloss of the treated surface (pressure gloss).

The invention therefore primarily relates to a method for improving the holdout of printing inks, lacquers and coating compositions, containing organic solvents, on fabrics made of fibers, in particular on paper, and for improving the de-inking of the fibers by introducing water-insoluble substances into the fiber mass or in the surface of the fiber structure.

• (a) einem wasserunlöslichen hydratisierten kationenaustauschfähigen filmbildenden smektitischen Schichtsilikat mit einer lonenaustauschfähigkeit von wenigstens 50 mVal/100 g und
• (b) einem daran gebundenen, aus einer Oniumverbindung abgeleiteten organischen Rest in die Fasermasse oder in die Oberfläche des Fasergebildes einbringt, wobei der organophile Komplex durch Reaktion mit dem organischen Lösungsmittel eine Sperrschicht bildet.
• Der organische Rest, der in der Regel ein Molekulargewicht von weniger als 1000 hat, ist in einer Ionenbindung an das anorganische Schichtsilikat gebunden. Die Eigenschaft des anorganischen Schichtsilikats, in wäßriger Phase ein Gel zu bilden, ist offenbar wichtig, damit auch der organophile Komplex mit dem organischen Lösungsmittel reagiert und unter Gelbildung aufquillt. Da der organische Rest über eine Ionenbindung an das anorganische Schichtsilikat gebunden werden soll, hat das anorganische Schichtsilikat zweckmäßig ein hohes Ionenaustauschvermögen.

The process is characterized in that an organophilic complex is formed

• (a) a water-insoluble, hydrated, cation-exchangeable film-forming smectic layered silicate with an ion exchange capacity of at least 50 meq / 100 g and
• (b) introduces an attached organic residue derived from an onium compound into the fiber mass or into the surface of the fiber structure, the organophilic complex forming a barrier layer by reaction with the organic solvent.
• The organic residue, which usually has a molecular weight of less than 1000, is bound to the inorganic layered silicate in an ion bond. The property of the inorganic layered silicate to form a gel in the aqueous phase is obviously important so that the organophilic complex also reacts with the organic solvent and swells to form a gel. Since the organic residue is to be bound to the inorganic layered silicate via an ion bond, the inorganic layered silicate expediently has a high ion exchange capacity.

It is believed that the organophilic complex with the organic solvent gives a more or less strong swelling reaction. This swelling reaction is surprisingly so strong and so fast that the capillary forces of the fibrous sheet or even a line, especially a sheet of natural paper, do not take effect. That possibly also an adsorption of the colors or their binders on the particles of the organophilic complex takes place, is of minor importance, since the holdout behavior of the treated surface for the pure solvent is practically as great as for the solution or dispersion of the printing ink of the Paint or the coating composition.

To produce the organophilic complex, for example, a fully hydrated, cation-exchangeable, colloidal film-forming smectic layered silicate with an ion exchange capacity of 50 to 130, preferably 70 to 100 meq / 100 g is used. To generate the organophilic complex, at least 50% of the exchangeable cations are preferably replaced by organic residues. If the organophilic complex is to be processed further in the organic phase, an exchange of the cations in the vicinity of 100% is preferred. If the organophilic complex is to be dispersed in an aqueous phase, the degree of exchange is preferably about 20 to 60%.

Montmorillonite, hectorite, saponite, sauconite, beidellite and / or nontronite are preferably used as smectitic layered silicate to produce the organophilic complex.

Bentonite, which is available as a mineral substance with different exchangeable cations (Na, Ca, Mg) and whose main constituent is montmorillonite, is generally used as a smectitic layered silicate for practical purposes.

It is known from the reference "Das Papier", 35th year, volume 9, pages 407 and 416 (1981) to treat kaolin with cationic polymers in order to increase the filler content in the paper with the same strength. However, the kaolin has too little ion exchange capacity for the purposes of the present invention. In addition, kaolin is not film-forming in the aqueous phase and cannot be hydrated to form a gel.

The organophilic complexes are preferably reaction products of the inorganic sheet silicate with an organic ammonium compound, preferably a quaternary ammonium compound; instead of the quaternary ammonium compound, other organic compounds with a quaternary onium ion, e.g. quaternary phosphonium compounds can be used. Further usable organophilic complexes are also the partially reacted complexes of the layered inorganic silicates with quaternary onium compounds.

While the organophilic complex tends to flocculate when the reactive valences are _{fully utilized} , organophilic complexes with partially converted inorganic phyllosilicates, especially in aqueous dispersions, can often still be colloidal solutions. Of course, only the converted part reacts with the organic solvents of the printing ink, the lacquer or the coating compound.

However, since the fine distribution in a sheet of paper or in its surface is important for the process according to the invention in order to eliminate the capillary suction forces in the micro range as well, a preferred application for all aqueous systems is partial conversion, which results in a higher entry or application leads.

It can probably be assumed that the suitable organophilic complex will become an integral part of the gravure printing ink or the coating composition or the lacquer after drying. This is important for the so-called de-inking, since the organophilic complex separates from the fiber together with the color, the lacquer or the coating material.

The wettability of the printing inks, especially gravure printing inks, is particularly favorably influenced by the oleophilic character of the organic residues of the organophilic complex which face outwards.

According to the invention, all solvents used for dissolving or dispersing printing inks, lacquers, coating compositions or adhesives are suitable as organic solvents. An organic solvent from the group of toluene is preferably used in gravure printing inks, Xylene or petrol, possibly in a mixture with higher-boiling components. Such components are common in printing technology and serve to influence the evaporation behavior when the printing ink dries. The usual coating solvents such as esters, acetone, alcohols, etc. are used for coating compositions.

The invention can also be used to improve the holdout of pressure-sensitive adhesive coating compositions. These coating compositions contain sticky resins such as polyacrylates and polyisobutylene, some of which are mixed with plasticizers. Preferred solvents for such coating compositions are those based on hydrocarbons, such as gasoline.

Since the organophilic complexes swell in organic solvents and / or are present in colloidal dispersions, generally only limited solids contents of up to 10% by weight can be achieved. The reactive organophilic complex is preferably in the form of a 1.5 to 10% dispersion. The dispersions of the reactive organophilic complexes according to the invention in organic solvents are strongly thixotropic, which is important for application, e.g. is cheap in a gravure printing unit with an anilox roller.

The organophilic complex can either be introduced into the fiber mass or into the surface of the fiber structure.

The process according to the invention can be used, in particular for the production of satined papers, in such a way that the reactive organophilic complex is introduced into the suspended fiber mass in aqueous dispersion before the sheet is produced, with or without the fillers.

A variant of the process according to the invention is characterized in that the organophilic complex is generated in situ in the fiber mass by reacting the inorganic layered silicate with the organic compound before the fabric is produced. Also with this implementation, e.g. with a quaternary ammonium compound, the filler suspension can also be provided instead of the fiber mass (pulp), or fibers and filler are already present as a total.

The advantage of generating in situ, _{e.g. B. In} the paper mill, is particularly the fact that the paper machine also acts as a dryer for the organophilic complex, so energy is saved.

If the two above-mentioned process variants are carried out in the paper mill, the usual fillers can be partially replaced by the organophilic complex. The usual retention aids and other additives, such as paints, can also be used.

A process variant which is particularly suitable for the production of coated, highly satinized papers is characterized in that the reactive organophilic complex, optionally with a binder, a surfactant and / or an inert coating pigment, in aqueous suspension in or on the surface of the fabric brings. For example, the usual white pigments which improve the opacity can be used as inert coating pigments.

If a line or a surface preparation is not expected to contribute to the opacity of a sheet of paper, but if only the print opacity is in the foreground and thus the ink consumption and gloss of the print, then a variant of this process can be used to situate the organophilic complex in situ generate the surface of the fabric by making the inorganic layered silicate in the form of an aqueous colloidal dispersion which optionally contains binders, surfactants and / or coating pigments, introduces them into the surface and then reacts with the organic compound. This is possible, for example, in all those coating machines that have two coating devices on each side, which is common today. Machines with two size presses are also particularly suitable. In this case, for example, in the first _L eimpresse a film-forming hydrated highly swellable bentonite abandoned. A separate binder is not required. The dilute solution of a quaternary ammonium compound is then applied in the second size press.

Another possibility, which only requires a size press or a similar application device, is that the inorganic layered silicate is introduced into the fiber mass in the form of an aqueous colloidal dispersion, which optionally contains binders, surfactants and / or pigments, and then only in the surface reacted with the organic compound to obtain the organophilic complex. In this case, preferably 3 to 5% by weight of the hydrated inorganic film-forming sheet silicate, based on the total substance in the paper pulp, is added.

Instead of generating the organophilic complex in situ in the surface, it can also be produced by reacting the inorganic sheet silicate with the organic compound in the presence of binders, surfactants and / or coating pigments and bringing the reaction product as a coating composition into or onto the surface of the fiber material.

All of these process variants for the production of coated papers are carried out in the paper mill.

A further method variant is characterized in DAB, if appropriate, with a binder and / or an inert coating pigment, for example an opacity enhancing pigment rganischen in a _D solvent as a pre-preparation by means of a solvent coating machine or a printing press in _D of the reactive organophilic complex brings the surface of the fabric, after which the printing ink (s), the lacquer or the coating composition are applied after an intermediate drying.

The reactive organophilic complex according to the invention can in principle be applied from the organic solution or dispersion to a so-called solvent coater at high speeds and in the widths of modern paper machines (about 7 to 8 meters).

The advantage of such solvent coating machines lies, inter alia, in the fact that there is every degree of freedom with regard to the application of the coat and the admixture of any opacifying pigments.

Since in rotogravure printing in many cases no ink runs in the first printing unit, but the paper is only "pre-stretched", since in some large printing plants there are still 4, 5 or 6 printing units per page that are not used in all cases, e.g. in the case of advertising printed matter, the method according to the invention can advantageously also be carried out in the printing house.

A printing unit, e.g. a simple screen gravure printing unit, can therefore be used in the process variant described above to produce an invisible form of the organophilic complex, which is dried as usual before the actual gravure begins.

The costs for gravure printing are limited if, as usual, 92 to 96% of the solvent is recovered. Since, according to the invention, the organic dispersant for the organophilic complex is the same as for the solvent for the subsequent printing inks, the joint recovery makes no problems. The pre-stretching unit, i.e. the first printing unit used here, can retain its function as such, because the form with the reactive organophilic complex can be printed over the entire surface and without registering.

With this method variant, it is also possible to introduce the organophilic complex only partially into the surface of the fabric. The printing ink appears glossy in these areas, while it strikes away in the other areas that do not contain any organophilic complex in the surface and therefore appears matt.

In general, the same or similar organic solvents can be used as dispersants for the reactive organophilic complex and the printing ink (s) or the lacquer or the coating composition.

The invention further relates to a mass for carrying out the method variants described above, which is applied to the surface of the fiber structure. This mass is characterized in that it is in the form of a dispersion of a reactive organophilic complex in an aqueous or organic medium.

The reactive organophilic complex is preferably in the form of a 1.5 to 10% dispersion, in particular in an organic solvent such as toluene or xylene. In an aqueous medium, the reactive organophilic complex is preferably in a 2 to 20% dispersion.

The invention further relates to fabrics made of fibers, in particular paper, which are characterized in that they contain in the surface and / or in the fiber mass a reactive organophilic complex which can be obtained by the process according to the invention.

If the organophilic complex is in the surface of the flat structures according to the invention, it is preferably present in a finely divided amount in an amount of 0.1 to 3, preferably 0.2 to 0.8 g / m ² and side. If it is in the fiber mass, it is preferably present in an amount of about 1.5 to 12% by weight. The invention can also be used, for example, for the production of zinc oxide papers. With these papers, a toluene varnish, which is filled with photoconductive zinc oxide and non-conductive binders, is spread onto the surface of a conductive base paper. The conductivity of the base paper is obtained by adding a conductive polymer (coneuctie polymer) to the size press preparation from starch ethers or starches or from polyvinyl alcohol. The toluene coating behaves analogously to a printing ink. Because of the barrier effect of the reactive organophilic complex in the fiber mass or in the surface of the fiber structure, the toluene lacquer filled with zinc oxide is prevented from penetrating into the fiber mass. Until now, it was only possible to achieve a holdout for toluene that is hole-free, only with great effort, partly double size press coating, partly pre-coating with the conductive polymer and the colloidal binder. By adding the reactive organophilic layered silicate in the size press preparation and / or in the primer, it is possible to achieve a spot-free toluene density for the subsequent coating.

Wherever the conductive base paper has a flaw, i.e. If toluene is absorbed, a defect in the image reproduction occurs in the surface of the zinc oxide paper. By using the reactive organophilic phyllosilicates according to the invention, these defects can be eliminated.

The present invention can also be used to prevent the penetration of lacquers such as nitro lacquer, zapon lacquer, plastic lacquer, spirit lacquer etc. into fiber structures. For example, label papers are coated with a so-called protective label varnish after printing so that the labels on the bottles are scrub-resistant and not unsightly due to the absorption of moisture.

In order for a label paper to be paintable, it usually has to be coated on one side. So-called natural label papers cannot be varnished because the varnish does not remain on the surface but penetrates into the fiber material. The reactive barrier layer made of the organophilic complex according to the invention prevents the label lacquer from penetrating into the fiber material.

In addition, it should be noted that the precoating of a paper surface or another sheet-like fiber structure with the spontaneously reacting organophilic complex materials can make it printable, in particular paintable and coatable from organic solution, for which this was previously not possible. In addition to the nonwovens, this includes the simple wood-containing and wood-free natural papers, including those that are not or hardly filled and that have not been satined.

From this point of view, the invention is particularly important for cardboard, where, whether coated or not, every satin finish and smoothing in a smoothing unit leads to an undesirable loss of volume and thus a loss of rigidity.

The invention is also suitable for the production of adhesive labels.

In most cases, PSA coatings are made from an organic solution of the adhesives. The impact behavior of the adhesive coating masses in the paper plays an important role. This is because they should hit the paper as little as possible. So far, in such cases, expensive glue press preparations such as Casein, or polyvinyl alcohol, tries to improve holdout. Here too, coating with the reactive organophilic complex not only leads to a reduction in the application of pressure-sensitive adhesive, but also enables the use of previously little or unsuitable fabrics, such as nonwovens or textiles. According to the invention, these materials can also be made printable.

If quaternary ammonium compounds are contained in the organophilic complexes, they influence the electrical properties of the fabrics according to the invention, e.g. the surface or volume resistance. These values play a role in printability. The modification according to the invention reduces the surface and volume resistances and thereby eliminates interference caused by electrostatic charges.

The invention is illustrated in a non-limiting manner by the examples below.

example 1

A semi-bleached needle sulfate pulp is pulped in a pulper at a consistency of 5% and at a pH of 7 to 7.8 and then brought to a degree of grinding of 26 ° SR (Schopper-Riegler) in a refiner.

This pulp is mixed in a ratio 25: 75 in a pulping center with a splinter-free wood pulp with a freeness of 78 ° SR. A separately produced kaolin slurry of 40% at a pH of 7 to 7.8 is mixed into the fiber mixture in a ratio of 70 parts of fibers to 30 parts of kaolin (all air dry). A slurry of 3.5% solids of a pre-swollen sodium bentonite with an ion exchange capacity of 90 mVal / 100 g is mixed into this total substance until, based on fibers and filler, 4% by weight of the bentonite has been introduced. The whole thing will take about 10 min. well mixed. A 4% strength aqueous solution of dimethyl-benzyl-alkyl- (C12-C22) ammonium chloride is then mixed in in an amount equimolar to the complete ion exchange.

After a mixing time of 15 min. After dilution to 0.6%, paper with a basis weight of 40 g / m ^{2 is} produced from this substance on a paper machine and dried to a residual moisture content of 8.5% by weight. Then the paper is satined on a super calender. It has a Bekk smoothness of 900 seconds with a density of 1.10 g / cm ³ . It contains about 5% by weight, based on the total input, of reactive organophilic bentonite. It has a toluene holdout (measured by the spotting method, with 0.05 ml toluene stained with Ceres red) of 65 seconds compared to 36 seconds for an otherwise identical paper without the organophilic bentonite. The organophilic bentonite adheres well to the fibers and fillers. The small amount of NaCl does not interfere in the wastewater.

Example 2

A commercially available organophilic bentonite coated with quaternary ammonium ions (Tixogel VZ ( ^R ) from _F a. Süd-Chemie AG) is mixed in a high-speed mixer with high shear forces as a dispersion with a solids content of 20% by weight in the presence of a nonylphenol ethoxylate type 15 min. sheared. This dispersion is admixed to the fibers produced as in Example 1 and then the kaolin slurry is added in an amount such that, based on the total, 6% by weight of the reactive organophilic clay are in the total. The sheet of 60 g / m ² produced in a conventional manner after dilution, adjustment of the pH to 5.8, has a content of 5.5 to 6% by weight of the organophilic clay. After calendering with heated steel rollers at 90 ° C, it has a smoothness of 1300 Bekk.-sec. and a toluene holdout of 50 sec.

Example 3

• 96 Teile Streichkaolin
• 4 Teile feindispergierter reaktiver organophiler Bentonit in Form einer 20 gew.-%igen wäßrigen Dispersion nach Beispiel 2

A wood-containing paper having 55 wt .-% proportion of semi-bleached Softwood kraft pulp and 45 wt .-% olzschliff proportion of _H and a basis weight of 38 g / m ² is coated with a coating of the following composition:

• 96 parts of coated kaolin
• 4 parts of finely dispersed reactive organophilic bentonite in the form of a 20% by weight aqueous dispersion according to Example 2

These components are mixed intensively in a caddy mixer. Then 4.5 parts of a plastic dispersion of a copolymer of styrene and acrylic acid as a gravure binder and an additional 1.5 parts of a fully saponified medium-viscosity polyvinyl alcohol are added. The pH is adjusted to 8.5. The solids content of the coating slip is adjusted to 50% by weight.

After the line of 7 g / m ² and page, a coated rotogravure paper is produced which, after satinizing, has a Bekk smoothness of 1500 to 1600 seconds and a toluene holdout of 65 seconds. A comparable coated rotogravure paper has a toluene holdout of 40 seconds.

Example 4

According to Example 1, a wood-containing, kaolin-filled, satined, gravure printing paper without bentonite or quaternary ammonium compound is produced in bulk. In a coating machine with two coating heads on each side and the respective intermediate drying, a 5% slurry of a commercially available bentonite, the exchangeable cations of which are 40% Na and 60% Ca, is applied in the first and third coating unit. The order is about 1.5 g / m ² and side.

After intermediate drying, a 4% solution of the quaternary ammonium compound from Example 1 is applied in the coating units 2 and 4 in the relation given there. This solution reacts by ion exchange in the surface with the bentonite to form the reactive organophilic complex. Since both the hydrated bentonite is film-forming and the reactive organophilic complex forms a film, even if it adheres poorly, the use of colloidal and / or disperse binders is not necessary.

Example 5

A wood-containing, highly filled paper which, according to EU-PS 0 017 793, was produced with a film-forming colloidal bentonite, the sodium-magnesium atomic ratio of which was 60:40, and, based on the paper, contains 2.5% by weight of the film-forming bentonite , is treated at the end of the dryer section of a paper machine using a conventional size press with the dilute 3% aqueous solution of the quaternary ammonium compound from Example 1. Since the fibers and fillers of this paper in any case carry a film of bentonite, albeit a thin one, this enters into ion exchange with the quaternary ammonium compound and results in the reactive organophilic complex according to the invention being present especially in the surface after renewed drying.
The resulting sodium and magnesium chloride does not interfere.

Example 6

So-called solvent coaters are found in many factories that deal with the finishing of paper. These are coating machines that use various organic solvents as solvents or dispersants instead of water and usually recover them from the exhaust air.

A wood-containing gravure printing paper with a basis weight of 40 g / m ² has a filler content of 18% by weight. Its opacity and print opacity are unsatisfactory.

A commercial bentonite (Tixogel VP ( ^R ) from Süd-Chemie AG) coated with quaternary ammonium ions is in the form of a dispersion with a solids content of 3.5% by weight in a solvent mixture of 99 parts by weight of toluene and 1 Part by weight of ethanol 10 min. dispersed in a high shear high-speed mixer. This dispersion is applied to both sides of the paper by means of a reverse roll coater, so that 0.5 g / m ^{2 of} application (air-dry calculated) result on each side.

While the uncoated paper has a toluene holdout of 5 seconds, the paper pretreated in this way has a toluene holdout of 60 seconds. Printing with a black gravure ink shows almost no show through on the back and an increased print gloss.

Example 7

There are four printing units per page in a gravure printing machine. However, only a three-color rotogravure should be printed. Usually the first printing unit is run without color in order to pre-rip the paper web.

In this first printing unit, a colorless pre-printing ink is pre-printed with a 3% by weight colloidal dispersion in toluene, produced analogously to Example 6, using a screen roller with a 70 screen and an engraving depth of 65 µm over the entire surface and regardless of registration. After the usual drying, this form applies an application of 0.3 g / m ² to the paper to be printed. While sec at a lightly filled wood-containing _N aturpapier the absorption time for dyed toluene solution is about 6., It yields at the "preprinted" paper at a coating of 0.3 g / m ² has a value of 70 sec. A further increase of the order of reactive organophilic complex from the toluene solution, for example 0.6 g / m ² does not give a higher value nor a sharper level of the colored toluene drop, since with a coating of only 0.3 g / m ² the printing paper was already fully sealed against toluene is.

Example 8

_Since the improvement of the holdout for solvent-based printing inks is associated with an increase in the gloss of the printing ink to its maximum value, there is the possibility in the first printing unit of partially printed areas with the 3% by weight colloidal dispersion in toluene according to Example 7 receive. All subsequent prints, which meet non-pretreated parts of the surface, fold away and result in a matt print.

All gravure inks that meet the pretreated surface parts remain on the printing surface and develop their maximum possible printing gloss. You can e.g. In an advertising printed matter, highlight the article to be priced in high gloss on a matt background.

It should be emphasized again for Examples 7 and 8 that when a colloidal dispersion of the reactive organophilic complex is pre-printed, a binder is not necessary because the film-forming ability of these products is large enough to ensure adequate adhesion.

In all cases in which one or more other printing inks are also printed on the form with toluene, it must be assumed that this form becomes an integral part of the entire print.

Example 9

A wood-free label paper is made from 60 parts by weight of highly bleached needle sulfate pulp with a freeness of 30 ° SR and 40 parts by weight of bleached birch sulfate pulp with a freeness of 45 ° SR. To improve the opacity, 10 parts by weight of kaolin, 5 parts by weight of TiO ₂ and 5 parts by weight of aluminum hydroxide are added. The paper is taken out with 2.5 parts by weight of resin glue with the addition of a melamine-formaldehyde resin to improve the wet strength at a pH of 4.6 as smooth paper on one side and heated to 136 ° C. at the end of the drying section in order to crosslink the melamine. Ensure formaldehyde resin. This label paper should be coated with a scouring varnish after printing.

The label printing is carried out in gravure printing, a dispersion of the reactive organophilic complex according to Example 6 in toluene being pre-printed in the first gravure printing unit. After graphic printing, the protective label varnish is applied as a nitro varnish. It does not penetrate the natural printing paper treated according to the invention, although it has not been deleted.

It is advisable to use the same organic solvent in all cases of Examples 7, 8 and 9, if appropriate also with admixtures of high boilers, so that the condensate obtained from a solvent recovery system can be reused uniformly.

Example 10

A non-coated chromo replacement cardboard with a basis weight of 300 g / m ² was printed with a dispersion according to Example 6 by gravure printing, the dried application being only 0.2 g / m ² . A nitro lacquer, which would otherwise be knocked off, remains shiny on the pre-treated cardboard.

Example 11

A nonwoven fabric made of 80% polyester fiber and 20% bleached needle sulfate pulp as a dispersing fiber is impregnated with a plastic dispersion of polyacrylic acid ester after it has been produced in an aqueous suspension on a steep sieve machine.

This nonwoven is to be prepared for textile screen printing. Similar to gravure inks, screen printing inks are low-viscosity and contain toluene as a solvent.

In a conventional coating slip for organic solvents, a 3.5% by weight suspension of the organophilic complex according to Example 6, which is blended with a further 5% by weight of a fine calcium carbonate and contains a 2% by weight polyvinyl acetate additive, spread out. It is advisable to choose the knife coating process so that the large pores of the nonwoven material close.

While a toluene-containing screen printing ink has a toluene holdout of 10 to 15 seconds for an untreated nonwoven, the holdout is improved by the line to about 40 seconds. The print gloss that can be achieved is increased and the consumption of screen printing ink is reduced.

Example 12

A swollen Na-Mg-bentonite slurry with 5% by weight solids is mixed into a suspension of bleached needle sulfate pulp of 4.5% by weight consistency and a freeness of 23 ° SR until a 10th, based on the pulp wt .-% share is reached.

Then a bleached birch sulfate pulp of 4.5% by weight consistency with a freeness of 40 ° S _{R is} mixed in, namely in a ratio of 1: 2 needle pulp to birch pulp. The content of Na-Mg bentonite, calculated on total fibers, is now 3.3% by weight.

A 3% by weight solution of the quaternary ammonium compound according to Example 1 is prepared in a separate dissolving vessel.

This solution is added in an amount sufficient to exchange 30% of the exchangeable cations, with intensive mixing of the fiber-bentonite mixture. The wood-free paper thus produced using standard methods has a Bekk smoothness of 1100 sec. At 80 g / m ² , a density of 1.35 g / cm ² and a toluene holdout by the drop method (toluene colored with Ceres red) of 15 sec compared to 3 seconds for untreated paper.

Claims (20)

1. A method for improving the holdout of printing inks, varnishes and coating compositions containing organic solvents on fabrics made of fibers, in particular on paper, and for improving the de-inking of the fibers by introducing water-insoluble substances into the fiber mass or into the surface of the Fiber structure, characterized in that an organophilic complex (a) a water-insoluble, hydrated, cation-exchangeable film-forming smectic layered silicate with an ion exchange capacity of at least 50 meq / 100 g and (b) an attached organic residue derived from an onium compound introduces into the fiber mass or into the surface of the fiber structure, the organophilic complex by reaction forms a barrier layer with the organic solvent. 2. The method according to claim 1, characterized in that one uses an anionic layered silicate with an ion exchange capacity of 50 to 130 meq / 100 g and to generate the organophilic complex at least 20% of the exchangeable cations by organic residues. exchanges. 3. The method according to claim 1 or 2, characterized in that one uses for the production of the organophilic complex montmorillonite, hectorite, saponite, sauconite, beidellite and / or Montronite. 4. The method according to any one of claims 1 to 3, characterized in that the inorganic layered silicate is reacted with an organic ammonium compound, preferably a quaternary ammonium compound. 5. The method according to any one of claims 1 to 4, characterized in that an organic solvent from the group of lacquer solvents or from the group of solvents for printing inks is used. 6. Process according to one of Claims 1 to ⁴ , characterized in that the reactive organophilic complex is introduced into the suspended fiber mass in aqueous dispersion before the fabric is produced. 7. The method according to any one of claims 1 to 4, characterized in that the reactive organophilic complex is generated in situ in the fiber mass by reaction of the inorganic layered silicate with the organic compound before the production of the fabric. _{8. The} method according to any one of claims 1 to 4, characterized in that one brings the reactive organophilic complex, optionally with a binder, a surfactant and / or an inert coating pigment, in aqueous suspension in or on the surface of the fabric. 9. The method according to any one of claims 1 to 4, characterized in that the reactive organophilic complex is generated in situ in the surface of the fabric by using the inorganic layered silicate in the form of an aqueous colloidal dispersion, optionally binders, surfactants and / or coating pigments contains, brings in or on the surface and then reacted with the organic compound. 10. The method according to any one of claims 1 to 4, characterized in that the organophilic complex is generated in situ in the surface of the fabric by containing the inorganic layered silicate in the form of an aqueous colloidal dispersion which may contain binders, surfactants and / or pigments , into the fiber mass and then reacted on the surface with the organic compound. ^11- Process according to one of claims 1 to ^4, characterized in that the reactive organophilic complex is produced by reacting the inorganic sheet silicate with the organic compound in the presence of binders, surfactants and / or coating pigments and the reaction product as a coating composition in or on the Brings surface of the fiber material. 12. The method according to any one of claims 1 to 4, characterized in that the reactive organophilic complex, optionally with a binder and / or an inert coating pigment, in an organic solvent as a preparation by means of a solvent coating machine or a printing machine in or on the surface of the fabric brings, after which the printing ink (s), the lacquer or the coating composition are applied after an intermediate drying. 13. The method according to claim 12, characterized in that the same or similar organic solvents are used as dispersants for the reactive organophilic complex and the printing ink (s) or the lacquer or the coating composition. 14. The method according to claim ₁₂ or ₁₃ , characterized in that one brings the reactive organophilic complex only partially on or in the surface of the surface image. 15. Mass for performing the method according to any one of claims 1 to 6, 3 and 11 to 14, in the form of a dispersion of a reactive organophilic complex in an aqueous or organic medium. 15. Composition according to claim 15, characterized in that the reactive organophilic complex is in the form of a 1.5 to 10% dispersion. 17. Fabric made of fibers, in particular paper, characterized in that it contains in the surface and / or in the fiber mass a reactive organophilic complex obtainable according to one of claims 1 to ₁₄ . 18. Flat structure according to claim 17, characterized in that the reactive organophilic complex is present in the surface in an amount of 0.1 to 3 g / m ² , preferably 0.2 to 0.8 g / m ² and side. 19. The sheet material according to claim 17, characterized in that the reactive organophilic complex is present in the fiber mass in an amount of 1.5 to 12% by weight. 20. Use of the composition according to claim 15 or 16 for de-inking of fabrics made of fibers treated with printing inks, lacquers and / or coating compositions.