US20040079515A1

US20040079515A1 - Latent heat accumulator, method for producing a latent heat accumulator, method for producing a film-type latent heat accumulator and method for coating a support material

Info

Publication number: US20040079515A1
Application number: US10/416,693
Authority: US
Inventors: Klaus Fieback; Dirk Buttner
Original assignee: Individual
Current assignee: RUBITHERM GmbH; Kraiburg TPE GmbH and Co KG
Priority date: 2000-11-23
Filing date: 2001-11-15
Publication date: 2004-04-29
Also published as: WO2002042705A2; DE10058101A1; AU2002214053A1; WO2002042705A3

Abstract

Latent heat accumulator body with an outer shell body comprising of a hard plastic or elastomer, in particular a thermoplastic elastomer, which is processable by injection techniques and a filling comprising latent heat accumulator material which is located in the interior of the shell body and has a working temperature range covering a temperature span ranging from below to above phase change temperature, wherein the latent heat accumulator material is a gelatinous or solid mass in the working temperature range, independently of the temperature, and is introduced into the interior of the shell body by a two-component injection method.

Description

The invention relates in the first instance to a latent heat accumulator body with a shell body consisting of a plastic which can be processed by injection techniques and a filling consisting of a latent heat accumulator material which is located in the interior of the shell body and has a working temperature range covering a temperature span ranging from below to above the phase change temperature.

Latent heat accumulator bodies of this type have already been disclosed in various forms. Reference is made for example to DE 25 52 698 A1. However, the known latent heat accumulator bodies are not yet satisfactory in every respect. Apart from a relatively complex production method, inhomogeneous heat emission and absorption also give reason for complaint. This is at least the case whenever the interior of the shell body is only partly filled, which is generally required in the case of latent heat accumulator bodies of this type.

On this basis, the invention is concerned with the object of providing an improved latent heat accumulator body.

This object is achieved in the first instance and substantially by the latent heat accumulator body being a gelatinous or solid mass in the working temperature range, independently of the temperature, and being introduced into the interior of the shell body by means of a two-component injection method. The working temperature range is understood as meaning that temperature span which the phase change material producing the latent heat accumulation and emission, such as paraffin or a salt for instance, usually passes through in an accumulator cycle. This temperature span may vary, since the phase change material can be selected with regard to different phase change temperatures according to the intended use. If, for example, the phase change temperature is at 60° C., the range from about 70° C. to below 60° C., that is down to the ambient temperature or even lower, can be referred to as the working temperature range. As a result of the fact that the latent heat accumulator material is a gelatinous or solid mass, very homogeneous overall heat absorption and heat emission characteristics of the latent heat accumulator body can easily be achieved. The outer shell region may be completely closed. This can take place for example by subsequently injecting plastics material that forms the shell body, once it has already been injected in a first step for the basic forming of the shell body and the latent heat accumulator material has been injected in a second step. Alternatively, however, the latent heat accumulator material may also extend into the outer shell body. Although this extent may, in principle, still be covered by a plug-like part, it may still be exposed to the outside, forming part of the outer surface of the latent heat accumulator body.

It is also preferred for the latent heat accumulator material to fill the shell body completely, within the working temperature range, independently of the temperature. This is achieved in particular by the latent heat accumulator material being introduced, in particular injected, into the shell body at a temperature far above the phase change temperature of the phase change material respectively used, to be precise at such a pressure that complete filling of the shell body is obtained even after the latent heat accumulator material has cooled down to a temperature below the phase change temperature. In particular, this also achieves the effect that, in the working temperature range of the latent heat accumulator material, the latter is accommodated in an almost pressureless state, or only with a slight positive pressure, within the shell body.

Suitable in particular in the present connection as latent heat accumulator material is such a material which is for example paraffin-based, which contains a copolymer component, such as for example a triblock, radial-block and/or multi-block copolymer. Paraffin, for example, as the phase change material is primarily responsible for providing the desired latent heat accumulator characteristics. Latent heat accumulator material may then also have different further constituents, such as for instance an oil-binding agent and/or a titanium dioxide component and/or a carbon or graphite component. In addition, a metal powder such as aluminum powder for instance. In addition, microwave-active substances may also be contained in capillaries of capillary bodies mixed into the latent heat accumulator material. Furthermore, chopped fibers may be admixed with the latent heat accumulator material.

With regard to the oil-binding agents, preferred are only, or at least used are those which bind short-chain CH molecules, with respect to paraffin those which absorb the components with a melting point of 40° C. or less. For example, a polyolefin may be used for this purpose. In particular, a polymerized polyolefin. More suitably, one from the substance group of alkines. Preferably a C-10-alpha olefin. In particular, a polyolefin such as that known by the trade name “Vybar”. This is a fully polymerized ethylenic hydrocarbon. On the other hand, this may also be accomplished for example by a component of pyrogenic silicic acid. Silicic acid of this type is known for example by the trade name EROSIL. The said polyolefin and the said pyrogenic silicic acid may also be used in combination. If the said silicic acid is used, the additional advantage is obtained that a certain thickening or thixotropic effect of the molten latent heat accumulator material is at the same time set. Moreover, the silicic acid can distinctly improve the mechanical properties of the—solidified—latent heat accumulator material, such as tensile strength, tear propagation resistance and tear resistance. This is attributed to the fact that such a silicic acid acts as a reinforcing filler on the copolymers or block polymers. The proportion of oil-binding agent with respect to the total mass of the latent heat accumulator material may lie between 0.1 and 20 percent by mass. Within the scope of the present patent application, the term percent by mass is chosen as based on the base amount of the phase change material, that is for example the paraffin. For example, 100 g of paraffin plus 20 percent by mass of admixture lead to 100 g of paraffin plus 20 g of admixture. The proportion of oil-binding agent, however, also results from the intended purpose of this: the proportion is chosen such that the dry formulation desired for example is reached or else only just reached.

With regard to a component of metal powder, in particular titanium oxide, here again in particular titanium dioxide or titanium-IV oxide, is preferred. It has surprisingly been found that the surface quality of the hardened latent heat accumulator material is distinctly improved. In particular if the latent heat accumulator material is processed in extruders or injection-molding machines. What is more, it has been possible to observe advantageous toughness of the latent heat accumulator material. With respect to titanium dioxide, even proportions of up to one percent by mass have very significant effects with regard to the aforementioned material properties.

Furthermore, as an alternative to or in combination with the aforementioned components, the latent heat accumulator material may also have a carbon or graphite component. Carbon may be used in any of the known modifications. The carbon/graphite component is advantageous in particular with regard to a microwave sensitivity of the latent heat accumulator material. This microwave sensitivity can be set very well by means of the proportion of graphite. It is preferred for graphite in the form of graphite powder to be used. In addition, such a graphite component is also advantageous with regard to the improved heat conducting properties achieved with it. The heating up of the latent heat accumulator material is advantageously influenced.

Furthermore, as an alternative to or in combination with the aforementioned components, in particular also as an alternative to or in combination with the aforementioned graphite, the latent heat accumulator material may also contain microwave-active substances contained in capillaries of mixed-in capillary bodies. The particle size distribution of such bodies having a capillary structure can be used to control the uniformity of the heating-up process in a microwave. The finer the distribution, the better the heating-up process proceeds. These microwave-active substances may be, for example, one of the known higher-boiling liquids, having dipole properties. In particular, they may be high-boiling alcohols. On account of the different surface tensions of the latent heat accumulator material on the one hand, possibly also with one or more of the mentioned additives, and of the alcohols, of the water etc. on the other hand, no exchange takes place, for instance in the course of passing through various heating and cooling cycles, between the latent heat accumulator material and for instance the alcohol. In particular, it is also advantageous to admix these capillary bodies with the alcohol for example contained therein, although it may for example merely be water, in the course of extruding the latent heat accumulator material taken as a basis here. The microwave-active substance may also be a low-boiling liquid, for example low-boiling alcohol. For instance whenever the sensitivity of the latent heat accumulator material to microwaves is intended to disappear after one or more uses. This may be the case, for example, if a finished part of this latent heat accumulator material is to be adapted to its future active form, for example by heating up to plastic deformability, without it later being heated once again to this extent in an unintended and uncontrolled manner by renewed microwave irradiation. An example of a low-boiling alcohol is, for instance, methanol and an example of a high-boiling alcohol is, for instance, decanol. The already mentioned graphite is also suitable as a microwave-active substance.

A further significant additive is constituted by chopped fibers, which can be admixed with the latent heat accumulator material. These may be, in particular, fibers which are not absorbent themselves which, on account of their inner structure, for example by a closed structure, which is filled with gas bubbles, similar to a closed-cell foam, or mechanical spring elements (for example microscopic spirals), which fibers or spring elements are capable of absorbing mechanical stresses produced by expansion of the paraffin and of respectively relaxing reversibly when the exposure to pressure subsides. With such chopped fibers and/or metallic elements, such as small spiral springs, a molded part produced from this latent heat accumulator material can not only absorb internal stresses, but surprisingly advantageous properties are also obtained with regard to a soundproofing effect. Elements of this type, in particular the said chopped fibers, absorb converted sound energy by mechanical deformation and labyrinth formation. The chopped fibers may be, for example, man-made fibers such as nylon fibers, polypropylene fibers etc. The elements, in particular the chopped fibers, may have a linear extent of about 0.1-2 mm.

The elements may also be elastically expanded or compressed when they are introduced into the latent heat accumulator material. In this way, a desired prestress can be imparted to the latent heat accumulator material. The elements themselves may also be hollow bodies, for example air-filled hollow bodies. They may also be elastically reversible elements, for instance in the form of spheres, such as in particular rubber spheres.

With regard to the paraffin, in principle all known types of paraffin can be used. That is in particular macroparaffins, intermedia paraffins and microcrystalline waxes. Unless a dry formulation is specifically desired, these may also be deliberately liquid components (low-melting n- and iso-alkanes and naphthenes). A special cut may also be selected, chosen such that it is comparatively narrow. A narrow cut means that it covers only chain lengths of few numbers. For example C14 to C16 or C20 to C23.

Since, as known, at least on an industrial scale, the cut always takes the form of a frequency distribution unless specific special precautions are taken, the measure explained above means that in any event the far greater proportion of a given amount of phase change material is formed by the chain lengths comprising few numbers. To be specific, the cut is performed according to the desired melting temperature or phase change temperature. In addition, it has proven also to be particularly advantageous to prefer the even-numbered, normal C chains (n-alkanes). These have, in the said isolation, a surprisingly high heat accumulating capacity when there is a phase change.

As an alternative or in addition to the paraffins obtained by vacuum distillation, synthetic paraffins, paraffins obtained by the Fischer-Tropsch process, can also be used. These so-called FT paraffins primarily comprise only normal paraffins. Over 90% are customarily n-alkanes. The rest are iso-alkanes. The chain length is C30 to about C100, with a gradation (also solidification point, SP) of about 68° C. to about 105° C. For the FT paraffins, reference is generally also made to the literature reference A. Kühnle in Fetten, Seifen, Anstrichmittel [fats, soaps, coatings], 1982, pages 156-162.

With regard to the copolymers which can be used for the latent heat accumulator material referred to here above, they may specifically be various polymers. For instance, diblock, triblock, radial-block and multi-block copolymers. Particularly preferred is the use of a copolymer known as Kraton, in particular “Kraton G”. This is thermoplastic rubber. The diblock copolymer may in further detail comprise styrenes and/or butylene and/or ethylene and/or propylene. These polymers produce a crosslinked, rigid gel. The latent heat accumulator material assumes this overall appearance. This is achieved by the block copolymers forming a three-dimensional network, by physical cross connections. The cross connections occur in the case of these block copolymers by the formation of submicroscopic particles of a particle block, which may also be referred to as domains. The cross connection of these insoluble domains can be achieved by factors which influence the cross connection density of the network, including the length of insoluble block domains, the length of soluble block domains and the number of cross connecting locations.

The invention also relates to a method for producing a latent heat accumulator body with an outer shell body which has an outer surface and consists of a hard plastic or a thermoplastic elastomer which can be processed by injection techniques, and to a filling consisting of a latent heat accumulator material which is located in the interior of the shell body, the shell body being produced by a plastics injection method.

To achieve efficient production here, the invention proposes that the shell body is produced together with the filling by the two-component plastics injection method, the filling having a phase change material and a copolymer component, such as for example a triblock, radial-block and/or multi-block copolymer.

For specifics with regard to the copolymers, reference is made to the foregoing statements. The same applies with regard to the phase change material, that may be, for example, a paraffin, as explained in detail, a salt or the like.

With regard to the method, it is further preferred for the processing of the latent heat accumulator material to be performed at a temperature between about 50° C. and about 250° C. In this respect it is also significant which injection pressure is used, since liquifying or liquid-like characteristics of the latent heat accumulator material occur in the said composition also as the result of high shearing forces.

Furthermore, it is preferred with regard to the injection method that the injection of the phase change material is performed without back pressure. It is also preferred for the phase change material to be conveyed in the injection machine by an extruder, the heaters of which are deactivated, or not present, possibly with the exception of a final heater in the conveying direction. If it is also required for the phase change material to have a liquid-like state during the actual injection, this state may be disadvantageous in the extruder with regard to the conveying action.

The article mentioned at the beginning, comprising the shell body and the filling, and also the method for producing such an article, as described above, can lead to very different articles with regard to the product. They may be plate-like and shell-like, long and short, also very small, down to granule-like bodies, which for example have diameters of 2 or more mm. In addition, apart from the spherical form described further below in still more detail, they may also have a rectangular or cuboidal form. Also other angled geometries. In principle, all such geometries which can also already be produced conventionally by a two-component plastics injection method.

With regard to the plastics forming the outer shell which can be processed by injection techniques, it is provided to use those which, at least taken on their own, do not go through a phase change in a working temperature range.

The invention also relates to a method for producing a film-type latent heat accumulator body, consisting of a latent heat accumulator material which contains a copolymer component, such as for example a triblock, radial-block and/or multi-block copolymer. For details, reference is made to the above statements.

A film-type latent heat accumulator body has not so far been disclosed.

The invention provides that the latent heat accumulator body is reduced in thickness by the rolling method. Consequently, a comparatively thick starting body is initially produced, for instance by the injection method. This is then reduced in thickness mechanically, that is by passing through a roller nip. Following the rolling method, stretching of the rolled latent heat accumulator body obtained in this way can also be carried out. For this purpose, the rolled latent heat accumulator body may be grasped at the edges, for example by means of tenterhooks, and these tenterhooks can be moved apart from one another in such a way that stretching takes place, and consequently further reduction in thickness and lengthening of the latent heat accumulator body.

The rolled and possibly stretched latent heat accumulator material can also be fixed in its previously achieved thickness by chill rolling. This is because the rolling and stretching is performed at an elevated temperature. At such an elevated temperature at which the support material in which the latent heat accumulator material as such is incorporated, that is for instance the network of the said copolymers, is plastically deformable in an easy way. The chill rolling consequently has the effect that the latent heat accumulator material at such a temperature is reduced in its temperature and so the thickness achieved is, as it were, “frozen in”.

The rolling is performed in a temperature range in which the latent heat accumulator material as a whole has a doughy to viscous-pasty consistency. Since the copolymers may be formulated differently with regard to their softening and plasticizing temperature, this applies to temperature ranges from 50 up to 150 and 200° C. In an actual example, a temperature of the latent heat accumulator material of from 1100 to 120° C. was recorded at a rolling temperature of 140° C. After cooling down, the latent heat accumulator material becomes rigid, but remains easily bendable.

The invention also relates to a film-type latent heat accumulator body, produced by a method in one of the embodiments as described above.

With regard to the film-type latent heat accumulator body, it is also further preferred for it to be formed such that it is permeable to water vapor diffusion. This can be achieved in various ways. In a first embodiment, by the film-type latent heat accumulator body obtained being perforated. These may be fine through-holes, for instance of the order of magnitude of one millimeter or a fraction of a millimeter up to several millimeters.

Furthermore, additives, which for instance lead to voids being formed by influencing the crystal structure, may be added to the latent heat accumulator material as a whole or the phase change material, on the one hand, and to the copolymer material, on the other hand, possibly separately in each case.

These may be, for example, structure additives based on polyalkyl methacrylates (PAMA) and/or polyalkyl acrylates (PAA) as single components or in combination. With regard to a phase change material such as paraffin, it has been observed that this involves the formation at crystal level of hollow cones, which are no longer capable of forming networks. In general, also suitable as structure additives are ethylene vinyl acetate copolymers (EVA), ethylene propylene copolymers (OCP), diene-styrene copolymers, both as single components and in a mixture, and also alkylated naphthalenes (Paraflow). The proportion of the structure additives begins with a fraction of percent by weight, referred to the latent heat accumulator material as a whole, realistically about 0.01 percent by weight, and exhibits noticeable changes in the sense of an improvement of the ability to allow water vapor to flow through, particularly up to a proportion of about 1 percent by weight. However, a higher proportion may also be suitable. In this connection, in particular with regard to the structure additives, reference is made to the disclosure of WO 94/12588, the content of which is hereby incorporated in full, including for the purpose of incorporating features of this disclosure in the claims of the present patent application.

The invention also relates to a method for coating a support material, such as in particular a textile material, with a latent heat accumulator material.

To achieve a coating efficiently and advantageously here, the invention proposes that the latent heat accumulator material is formed for example on the basis of paraffin, has a copolymer component, such as for example a triblock, radial-block and/or multi-block copolymer, which latent heat accumulator material is heated to a liquid state and in any event applied in a viscous state to the support material. This may be carried out for example by simple pouring on and subsequent smoothing with a doctor blade.

As an alternative to this, it may also be provided that the said latent heat accumulator material, formed as thin film-like bodies, is thermoformed together with the support material for bonding with the latter in a coating manner.

As a further alternative, it may also be provided that the said latent heat accumulator material is applied to the support material in a coating manner by means of an extruder with a slot die.

The support material as such may take a wide variety of forms. For example, a nonwoven material or random fiber material, such as a fleece, also a carpet, woven textile fabric on any basis, for instance based on cotton, synthetic fabric such as nylon, polyester etc., glass fiber, aramid or carbon fiber, wool, linen, paper etc.

In further detail, it may be provided that the support material coated in this way is subjected to a rolling operation, that is to say it is rolled with the support material and latent heat accumulator material together as a laminate. In this way, an intimate bond between the support material and the latent heat accumulator material can be achieved or strengthened.

In addition, it may be provided that the laminate achieved in this way is cooled, in particular taking into consideration the fact that the method steps previously described are necessarily carried out at an elevated temperature. Since the temperatures may be up to 250° C. and the latent heat accumulator material can indeed store large amounts of heat, intensive cooling is required. In principle, the cooling may be carried out by means of chill rolls or by passing through a rolling nip of chill rolls.

However, it may also be recommendable after rolling with non-cooled or slightly cooled rolls, to subject the latent heat accumulator material or the laminate comprising the latent heat accumulator material and support material to cryogenic cooling. That is cooling by means of liquid nitrogen or the like. This cannot be suitably achieved with chill rolls but by passing through a cooling bed, also achieved for example by blowing on liquid nitrogen.

The invention also relates to a latent heat accumulator body with an outer shell body consisting of a hard plastic or elastomer which can be processed by means of an extruder.

In this connection, to obtain a latent heat accumulator body which can be easily produced, the invention proposes that a filling of latent heat accumulator material is arranged in the interior of the shell body and has a working temperature range covering a temperature span ranging from below to above the phase change temperature, the latent heat accumulator material being a gelatinous or solid mass in the working temperature range, independently of the temperature.

The filling is preferably introduced by the coextrusion method. Although the latent heat accumulator material which is used here with preference, that is one with a copolymer component, has very low viscosity in one of the configurations as described above in detail at elevated temperatures and elevated pressure, it has been found that processing by the coextrusion method can nevertheless be carried out. For instance by performing rapid cooling downstream of the extruder, for instance cryogenic cooling as also described above. Or by working with an end seal or plug, against which extrusion can be carried out.

With regard to the hard plastic or thermoplastic elastomer for the outer shell, reference is made to the materials already described in this respect further above with regard to the injection-molding technique. By contrast with the injection-molded bodies described, here the shell body is formed such that it is circumferentially fully closed and homogeneous. Only on the end faces is there an opening, produced as a result of the method. Here, however, a covering can be provided, for instance by welding on or fusing the opposite layer of the shell body to each other and the like.

The invention correspondingly also relates to a method for producing a latent heat accumulator body with an outer shell body from a hard plastic or elastomer which can be processed by means of an extruder, in particular a thermoplastic elastomer, it being provided that the interior of the shell body is filled with a latent heat accumulator material with a copolymer component and the shell body is produced together with the filling by the coextrusion method.

The invention is further explained below on the basis of the accompanying drawing, which however merely represents schematic exemplary embodiments. In the drawing: [0046]
FIG. 1 shows a representation of the production by injection techniques of a spherical latent heat accumulator body; [0047]
FIG. 2 shows a latent heat accumulator body, produced by the method according to FIG. 2; [0048]
FIG. 3 shows a schematic view of a rolling-reduction unit for the latent heat accumulator body; [0049]
FIG. 4 shows a schematic view of tenterhook stretching of a film-type latent heat accumulator body; [0050]
FIG. 5 shows a chill-rolling device for fixing an assumed thickness of a latent heat accumulator body, rolled or stretched in a way corresponding to the procedure represented in FIGS. [0051] 3 and/or 4;
FIG. 6 shows a coating installation for coating a support material with latent heat accumulator material; and [0052]
FIG. 7 shows a perspective view, cut into on one side, of a body produced by the coextrusion method.[0053]
Represented and described in first instance, with reference to FIG. 1, is the production of a latent heat accumulator body in spherical form with an outer shell body and an inner filling of latent heat accumulator material. The latent heat accumulator body produced in this way is represented in FIG. 2 in cross-section. [0054]
The representations are of a purely schematic nature and serve only for explaining the method or the article in principle. [0055]
In FIG. 1 there can be seen, in the first instance, a [0056] screw extruder 1 and a screw extruder 2.
While in the [0057] first screw extruder 1 the plastics material of the shell body is processed and then discharged by an injection technique, the screw extruder 2 serves for the simultaneous processing of the latent heat accumulator material.
The plastic of the outer shell may be any known and suitable hard plastics or soft plastics that are usually processed by injection techniques. For instance, polypropylene, polyethylene, transparent thermoplastic, such as for example PMMA, PC, but also thermoplastic elastomers. [0058]
The latter also have the advantage that, depending on the pressure setting of the latent heat accumulator material injected into the interior space, they can still expand, which may be advantageous under certain conditions of use, if for instance a change in the diameter or volume of the latent heat accumulator body is specifically desired at elevated temperature. [0059]
In the first instance, the plastics material of the outer body is injected from the [0060] screw extruder 1 into the cavity 3. The cavity 3 is hereby only partly filled with this material. Then, the latent heat accumulator material is injected into the same cavity 3 from the screw extruder 2. The previously injected material for the shell body is hereby forced by the subsequently injected latent heat accumulator material to a great extent against the wall of the cavity 3. Repeated injection of plastics material from the screw extruder 1 then takes place, so that a completely closed shell body 5 is obtained as a result.
It can be seen from the cross-sectional representation of FIG. 2 that the latent [0061] heat accumulator body 4 produced in this way has an outer shell body 5 and an inner filling of latent heat accumulator material 6. A sprue does not occur in the case of this exemplary embodiment. However, a sprue which protrudes into an outer surface 8 of the shell body 5 may be provided in the case of an alternative embodiment. The latent heat accumulator material 6 then forms part of the outer surface of the latent heat accumulator body 4 in the region of the sprue.
With reference to FIGS. [0062] 3 to 5, the production of a film-type latent heat accumulator body is described.
The starting point is a molding or a basic latent [0063] heat accumulator body 9, produced for instance by the casting method. This basic body 9 is passed in a heated state through rolls 11, 12 in a roll stand 10, so that, with a pasty consistency, it is plastically deformable. A semifinished latent heat accumulator body 9′ is obtained, which is reduced with regard to its thickness d′ and also lengthened with regard to its length 1′ and widened with regard to its width b′. (The drawing is not to scale with respect to the ratio of the basic body to the body during rolling and the rolled body.) The basic latent heat accumulator body will generally have here a temperature of >100°, for instance 120° to 140° C. It may, however, also have a temperature of up to 240° C. To achieve the pasty consistency mentioned of the latent heat accumulator body as a whole, this depends on the composition of the copolymers.
In the case of the exemplary embodiment, the [0064] body 9 subsequently passes through the rolls 3″, 12 and straightaway also chill rolls 24, 25, 26.
The semifinished latent [0065] heat accumulator body 9′ obtained in this way is then further reduced in thickness, as schematically represented in FIG. 4, for example by stretching. With respect to the latter, the semifinished latent heat accumulator body 9′ is subjected to tensile loading at its circumference by tenterhooks 20 (merely schematic representation) in four directions R, R′, R″, R′″. The directions R, R″ and R′, R′″ are respectively opposed to one another, the directions R and R′ and R″ and R′″ extending at right angles to each other. The desired film-type latent heat accumulator body 9″ is obtained, as represented in FIG. 5. It has a film-like thickness d″ of approximately {fraction (1/10)} to 5 mm in thickness.
This latent [0066] heat accumulator body 9′″ is still in the temperature range in which the latent heat accumulator material is plastically deformable. In order to fix the latent heat accumulator body 9‘’ in this stretched form, it is then passed through chill rolls 14, 15, 15′, which, without performing a further thickness reduction, only serve the purpose of carrying out rapid cooling of the latent heat accumulator body 9″ and so, as it were, of “freezing in” the structure achieved.
As an alternative to the representation according to FIG. 4, a blowing method may be carried out with regard to the further thickness reduction. This then involves the latent [0067] heat accumulator body 9′ being pressed tightly at the edges against a sealing bar and, moreover, pressurized by gas, in particular air, so that it expands in the manner of a balloon and the further reduction in thickness is performed in this way. This may be advantageous in particular since the gas, or the air, can then also be heated to that temperature at which the plastic deformation of the latent heat accumulator material can be advantageously carried out.
With reference to FIG. 6, the coating of a support material is represented, as in the case of the example of a woven [0068] web 15. The latent heat accumulator material 17, heated to the liquid state and contained in a liquid storage tank 16, is poured onto the support material 15, which is moved in the direction of the arrow P on a transporting path 18. The support material 15 with the latent heat accumulator material 17 poured on then runs through a doctor blade 19, in which the desired coating thickness is set. Excess material is diverted to the side and can be fed back into the storage tank 16.
As an alternative to the method represented in FIG. 6, the coating may also be carried out directly with a slot-die extruder, the slot setting of the slot-die extruder then at the same time predetermining the desired coating thickness. [0069]
The coated support material achieved in this way is preferably then passed through chill rolls [0070] 14, 15, in a way analogous to the method step represented in FIG. 5, in order to fix the laminate achieved in this way.
Represented in FIG. 7 is a latent [0071] heat accumulator body 21 which is produced by the coextrusion method.
The latent [0072] heat accumulator body 21 has a shell body 22, which is rectangular in cross-section in the case of the exemplary embodiment and is filled with a filling 23 in the form of a latent heat accumulator material with a component of a phase change material and a component of copolymers, as already explained in detail above in various connections.
The [0073] shell body 22 consists of an extrudable hard plastic, as has been explained above also with regard to injection molding. That is for instance of polypropylene, polyethylene etc. If appropriate, the shell body 22 may also consist of an elastomer, in particular a thermoplastic elastomer.
The filling [0074] 23 fills the shell body 22 completely. For this purpose, it may be provided that, when extruding with respect to the fillings 23, such a pressure is used that this filling engages with prestress against the inner faces of the shell body 22.
This prestress correspondingly diminishes partly or largely or even completely as the coextruded body created in this way cools down. [0075]
All disclosed features are (in themselves) pertinent to the invention. The disclosure content of the associated/attached priority documents (copy of the prior patent application) is also hereby incorporated in full in the disclosure of the patent application, including for the purpose of incorporating features of these documents in claims of the present patent application. [0076]

Claims

1. Latent heat accumulator body with an outer shell body consisting of a hard plastic or elastomer, in particular a thermoplastic elastomer, which can be processed by injection techniques and a filling consisting of latent heat accumulator material which is located in the interior of the shell body and has a working temperature range covering a temperature span ranging from below to above the phase change temperature, characterized in that the latent heat accumulator material is a gelatinous or solid mass in the working temperature range, independently of the temperature, and is introduced into the interior of the shell body by means of a two-component injection method.

2. Latent heat accumulator body with an outer shell body consisting of a hard plastic or elastomer, in particular a thermoplastic elastomer, which can be processed by means of an extruder, characterized by a filling consisting of latent heat accumulator material which is located in the interior of the shell body and is a gelatinous or solid mass in the working temperature range, independently of the temperature.

3. Latent heat accumulator body according to one or more of the preceding claims or in particular according thereto, characterized in that the latent heat accumulator material completely fills the shell body in the working temperature range, independently of the temperature.

4. Latent heat accumulator body according to one or more of the preceding claims or in particular according thereto, characterized in that the latent heat accumulator material at the injection temperature or extrusion temperature is accommodated with positive pressure in the shell body.

5. Method for producing a latent heat accumulator body with an outer shell body which has an outer surface and consists of a hard plastic or elastomer, in particular a thermoplastic elastomer, which can be processed by injection techniques, and a filling consisting of latent heat accumulator material which is located in the interior of the shell body, the shell body being produced by the injection molding method, characterized in that the shell body is produced together with the filling by the two-component plastics injection method, the filling having a phase change material and a copolymer component, such as for instance a triblock, radial-block and/or multi-block copolymer.

6. Method for producing a latent heat accumulator body according to claim 5 or in particular according thereto, characterized in that the injection of the phase change material is performed without back pressure.

7. Method for producing a latent heat accumulator body according to either of claims 5 and 6 or in particular according thereto, characterized in that the phase change material is conveyed in the injection machine by an extruder, the heating of which is switched off or greatly reduced.

8. Method for producing a latent heat accumulator body according to one of claims 5 to 7 or in particular according thereto, characterized in that the phase change material is conveyed in the injection machine by a cooled extruder.

9. Method for producing a film-type latent heat accumulator body, consisting of a latent heat accumulator material which is for example paraffin-based, containing a copolymer component, such as for example a triblock, radial-block and/or multi-block copolymer, the latent heat accumulator material being reduced in thickness by the rolling method.

10. Method according to claim 9 or in particular according thereto, characterized in that, following the rolling method, stretching of the basic latent heat accumulator body obtained in this way is carried out.

11. Method according to one or more of the preceding claims or in particular according thereto, characterized in that the rolled and possibly stretched material is fixed in its thickness by chill rolling.

12. Method for coating a support material such as a textile with a latent heat accumulator material, characterized in that the latent heat accumulator material, chosen on the basis of paraffin for example, has a copolymer component, such as for example a triblock, radial-block and/or multi-block copolymer, which latent heat accumulator material is heated to a liquid state and is applied in this state to the support material to the support material.

13. Method according to the features of the precharacterizing clause of claim 12 or in particular according thereto, characterized in that the latent heat accumulator material, formed on the basis of paraffin for example, has a copolymer component, such as for example a triblock, radial-block and/or multi-block copolymer, which latent heat accumulator material, formed as a thin film-like body, is thermoformed together with the support material for bonding with the latter in a coating manner.

14. Method according to the features of the precharacterizing clause of claim 12 or in particular according thereto, characterized in that the latent heat accumulator material, formed on the basis of paraffin for example, has a copolymer component, such as for example a triblock, radial-block and/or multi-block copolymer, which latent heat accumulator material is applied to the support material in a coating manner by means of an extruder with a slot die.

15. Method according to one of claims 12-14 or in particular according thereto, characterized in that the support material is a fleece, carpet etc.

16. Method according to one of claims 12-15 or in particular according thereto, characterized in that the coated material is rolled.

17. Method according to one of claims 12-16 or in particular according thereto, characterized in that the coated material is cooled by means of chill rolls.