MXPA00006280A - Laminating adhesive hardenable by radiation and use of same - Google Patents

Abstract

The invention relates to the use of an adhesive containing at least two components A and B for producing composite film materials. The component A present in the adhesive contains a compound having at least one vinyl ether group with a molecular weight of more than 400, and component B contains a photo-initiator which after irradiation with light at a wave length of between 100 and 600 nm initiates a polymerisation of component A. The invention yields composite film materials having high heat-resistance and high flexibility. The invention further relates to an adhesive suitable, forexample, for the production of composite film materials.

Description

RADIATION HARDENED LAMINATION ADHESIVE AND ITS USE The invention relates to the use of an adhesive containing at least two components A and B for the production of composite film materials. Furthermore, the present invention relates to the use of a lamination adhesive of this type curable by means of irradiation for the manufacture of composite film materials. Within the field of adhesives, especially in the case of flat lamination materials, there is an increasing demand for shorter hardening times and a shorter "response time" (faster use capacity) of the adhesives used for lamination. Common commercial systems are based, in general terms, on polyurethane, acrylate or epoxy binders that harden through reaction with additional hardeners or through moisture by relatively slow crosslinking. The usual hardening time of such systems that can be achieved in the market is from about 4 to about 21 days. However, in general terms, a period of this type until the final hardening and consequently until reaching a loading capacity as large as possible for composite film materials is not desirable. The composite film materials are subjected during manufacture, preparation and use to a series of strength that are typically not found in the case of other glued materials or not in the magnitude with which they are applied to composite film materials. In the case of the manufacture of composite film materials, totally different materials are used, which may have a different surface structure. In general terms, these are flat materials made, for example, from paper, plastics with plastic sheets or metal sheets, especially aluminum foil with application of metal or metal oxides, especially transition metal oxides. The composite film materials are subjected during processing, preparation and use to a series of mechanical loads that pose high requirements to the adhesive that constitutes the union between the materials with respect to the mechanical properties of the adhesive. Since in general, in the case of flat adhesive materials of high flexibility materials which are constantly subjected during manufacture, preparation and use to detachment and bending movements, the adhesive must have a sufficiently high flexibility to be able to withstand to the forces without damage or separation of the adhesive bond. In addition, the adhesive must also have sufficient peel strength such that it can resist orthogonal peel forces relative to the sheet jointing surface without separation of the constituents. The adhesive must also, in general terms, also in relation to the tendency to crystallization and coloration, present a series of criteria that exceed the performance characteristics of adhesives for usual adhesions. Thus, for example, in the case of the adhesion of transparent plastic films, it must be ensured that the bonding of the films presents a lasting transparency without clouding due to crystallization. Likewise, the adhesive should also present, even in the case of long storage of the films, for example in the case of UV irradiation, a tendency as little as possible to the formation of colored by-products.

The composite film materials must also present the greatest possible resistance to temperature within the shortest possible time. This property is especially important in the case for example of products with a short production and packaging cycle that must be packaged with composite film materials while still at an elevated temperature. The heat resistance characteristic is however also important when materials wrapped at least partially in a composite film material must be subjected to heating.

A criterion of quality that has an increasing importance for composite film materials is represented by the absence of migrant elements as much as possible. By migrating elements we mean constituents of low molecular weights of the composite film material which are not stable within the composite material ie they can move within the composite material and on the other hand eventually leave the composite material and can diffuse into the material wrapped by the composite material. Since such low molecular weight constituents can affect the health of living beings, especially humans, it is desirable to provide composite film materials free of migrating elements as much as possible. Radically polymerizable components are known through irradiation in the adhesives. The drawback is that in the case of such radical polymerizable adhesives, which in general terms must be hardened under inert conditions, since the oxygen in the air has an inhibiting effect. For example, this material to be polymerized is obtained through irradiation in. an atmosphere of inert gas where as inert gases we can contemplate, for example, nitrogen or argon. A disadvantage in the case of this method is that it requires a significant investment in apparatus in order to ensure required inert conditions. DE-U 94 20 640.6 relates to compositions curable by irradiation with a content of OH-terminated polyurethanes, an epoxy compound and a photoinitiator. A one-step irradiation curable adhesive composition having both high initial adhesion and high final adhesion when used as a lamination adhesive is described. EP-A 0 668 804 describes cationic hardening epoxy masses, of multiple components as well as a process for hardening them. Said document discloses cationic hardening epoxide masses in various embodiments which, as a fundamental part, in general terms, contain a mixture of compounds made from the irradiation of Lewis acids and / or Bronsted acids, monomers containing cationically polymerizable epoxide groups. as at least one additional component selected from the group of flexibilizing agents, retardants, radical polymerizable monomers, accelerators or modifiers. As flexibilizing agents, retarders, radically polymerizable monomers, accelerators or modifiers. As flexibilizing agents we mentioned glycol alcohols with a molecular weight of at least 200 to 20,000 g / mol. DE-A 43 40 949 discloses light-initiating cationic epoxide masses and their use. The document discloses a mass of cationic initiating epoxide initiated by light containing at least one retardant, at least one accelerator, at least one ferrocenium complex salt and at least one compound containing epoxide, cycloaliphatic, as well as auxiliary and usual additives. The adhesives represented in the state of the art present, in general terms, the disadvantage that they do not meet all the requirements that an adhesive is required for the production of composite film materials. Thus, although quick-hardening adhesives can be prepared from epoxy and polyurethane-polyol compounds, however, their resistance to heat does not meet the requirements, for example in the case of food preparation or in the case of sterilization of medical instruments. Accordingly, it is an object of the present invention to provide an adhesive system for the manufacture of composite film materials that can withstand the high requirements during the manufacture, preparation and use of such composite film materials. and that also present a fast hardening time as well as a high resistance to detachment and cutting. Furthermore, the object of the present invention is to provide an adhesive for the production of composite film materials with which composite film materials with high heat resistance and low content of migrating elements (for example low molecular weight polyols) can be obtained. . The object of the present invention is solved through an adhesive containing at least two components A and B, in accordance with what is described below within the framework of this text. The object of the present invention is the use of an adhesive containing at least two components A and B for the manufacture of a composite film material, where (a) as component A contains a compound with at least one vinyl ether group with a molecular weight greater than 400, and (b) as component B contains a photoinitiator which, after irradiation with light with a wavelength of 100 to 600 nm, initiates a polymerization of component A. The compounds that can be used within the framework of the present invention as component A have a weight more than about 400. For example, component A may contain only one compound with at least one vinyl ether group, however it is also possible to employ a mixture of two or more compounds with at least one vinyl ether group. By "mixture" we mean in this context not a mixture of different molecules of a single polymeric compound as it is obtained in general terms based on the statistical division of molecular weights at the moment of effecting the synthesis of a polymeric compound (according to the method of synthesis selected) . The concept "mixture" refers in this context to the fact that at least two polymeric compounds coming from different syntheses are mixed. The polymeric compounds can be differentiated, for example, in the distribution of molecular weights, that is, in that the values in terms of average number of molecular weight (Mn) and / or average weight of molecular weight (Mw) are different. . In general terms, however, the term "mixture" represents a mixture of at least two different polymeric compounds that were synthesized for example with the aid of different monomers. The polymeric compounds used as component A have a polymer structure that was prepared by polycondensation, polyaddition or polymerization or by the simultaneous or successively use of the methods indicated for the polymer construction by synthesizing a polymer. The compounds to be used as component A within the framework of the present invention have at least one vinyl ether group which is either in the final position, ie at one end of a polymer chain or is in a position lateral, that is to say, that is covalently bound to the polymer chain as a side group. The bonding of a polymer with a vinyl ether group can be achieved in various ways, where it is considered preferable within the framework of the present invention when a bonding of the polymer chain with the vinyl ether group is achieved for example by placing a group of vinyl ether in a polymer chain with the aid of at least one OH group which is in the polymer chain. Correspondingly, the main chain of the compounds that can be used as component A within the framework of the present invention can be, for example, a polyamide, a polyester, a polyether, a polyacrylate, a polymethacrylate, a polycarbonate or a polyurethane or a copolymer containing two or more of the polymer structures mentioned. Within the framework of the present invention, polymeric compounds of this type are preferred which have at least one OH group in the polymer chain before the addition of the vinyl ether group. These include, for example, polybutadiene or polyisoprene with OH end groups. Processes for the preparation of polymers carrying OH groups of the aforementioned type are known to the person skilled in the art from the macromolecular chemistry literature and need not be explained here. The polymers which carry OH groups are especially easily and advantageously provided with vinyl ether groups. For this purpose, starting usually with monohydroxyvinyl ethers, which can be obtained, for example, by the reaction of acetylene with a polyol, preferably a diol. The monohydroxyvinyl ether can then be reacted, for example, with a polyisocyanate, so that the stoichiometric ratio between monohydroxyvinyl ether and the polyisocyanate is selected in such a way that a free isocyanate group remains at least per molecule after the reaction. Finally, the compound obtained in this way can react with a polymeric compound carrying OH groups, which leads to a compound having covalently linked vinyl ether groups. It is likewise possible to carry out an inverse process in which first the OH-carrying polymer reacts with a polyisocyanate in such a way that a polymer carrying isocyanate groups is obtained and this isocyanate-carrying polymer reacts with a monohydroxyvinyl ether. The polymers prepared in this way carry a urethane group in the final position or in the lateral position. Within the framework of the present invention, the term "polyurethane" also encompasses all polymeric compounds that are linked with a vinyl ether group through a urethane group according to that described above. In the case of the polyurethane used as the preferred component A according to the present invention, it is in particular polyester polyurethane or polyether polyurethane. A polyester polyurethane used as component A especially preferred within the framework of the present invention can be obtained from the reaction of a polyester polyol with a polyisocyanate and a monohydroxyvinyl ether. For the preparation of component A, polyester polyols with a molecular weight of between about 200 and about 10 are suitable., 000 For example, polyester polyols can be used which are obtained by reacting alcohols of low molecular weights, especially ethylene glycol, diethylene glycol, neopentyl glycol, hexanediol, butanediol, propylene glycol, glycerin or trimethylolpropane with caprolactone. Also as polyfunctional alcohols for the preparation of suitable polyester polyols, mention may be made of 1,4-hydroxymethylcyclohexane, 2-methyl-1,3-propanediol, butanediol-1,2,4, triethylene glycol, tetraethylene glycol, polyethylene glycol, dipropylene glycol, polypropylene glycol, dibutylene glycol and polybutylene glycol. . Also for the preparation of component A, mixtures of two or more of the mentioned alcohols are suitable.

Additional suitable polyester polyols are obtained by polycondensation. Difunctional and / or trifunctional alcohols with insufficiency of dicarboxylic acids and / or tricarboxylic acids, or their reactive derivatives can be condensed in polyester polyols. Suitable dicarboxylic acids are, for example, succinic acid and its higher homologs with up to about 16 carbon atoms, as well as unsaturated dicarboxylic acids, such as maleic acid or fumaric acid, and aromatic dicarboxylic acids, especially isomeric italic acids, such as, for example, acid italic, isophthalic acid or terephthalic acid cr mixtures of two or more of the aforementioned dicarboxylic acids. Suitable tricarboxylic acids are, for example, citric acid or trimellitic acid. Within the framework of Xa present invention, polyester polyols are particularly suitable from at least one of the aforementioned dicarboxylic acids and glycerin, which have a residual content of OH groups. Especially suitable alcohols are hexandiol, ethylene glycol, diethylene glycol or neopentyl glycol or mixtures of two or more of them. Especially suitable acids are isophthalic acid or adipic acid or its mixture. Polyester polyols with high molecular weight include, for example, the products of the reaction of polyfunctional alcohols, preferably difunctional alcohols (optionally together with small amounts of trifunctional alcohols) and polyfunctional carboxylic acids, preferably diffused to the es. Instead of using free polycarboxylic acids, it is also possible (when possible) to use the corresponding polycarboxylic acid anhydrides or the corresponding polycarboxylic acid esters with alcohols having preferably 1 to 3 carbon atoms. The polycarboxylic acids can be aliphatic, cycloaliphatic, aromatic and / or heterocyclic. They may optionally be substituted, for example, by alkyl groups, alkenyl groups, ether or halogen groups. Suitable polycarboxylic acids are, for example, succinic acid, adipic acid, suberic acid, azealinic acid, sebacic acid, italic acid, isophthalic acid, terephthalic acid, trimellitic acid, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, tetrachlorophthalic acid anhydride, endomethylenetetrahydrophthalic acid anhydride, glutaric acid anhydride, maleic acid, maleic acid anhydride, fumaric acid, dimeric fatty acid or trimeric fatty acid or mixtures of two or more of them. Eventually lower amounts of monofunctional fatty acids can be found in the reaction mixture. If a polyether polyurethane is used as component A, then, as a basic polyether, for example, a reaction product of low molecular weight polyfunctional alcohols with alkylene oxides is suitable. The alkylene oxides preferably have from 2 to about 4 carbon atoms. Suitable, for example, are the reaction products of ethylene glycol, propylene glycol, isomeric butanediols or hexandiols with ethylene oxide, propylene oxide and / or butylene oxide. Furthermore, the reaction products of polyfunctional alcohols such as glycerin, trimethylolethane and / or trimethylolpropane, pentaerythritol or sugar alcohols with the aforementioned alkylene oxides to obtain polyether polyols are also suitable. Polyether polyols with a molecular weight of from about 100 to about 10,000, preferably from about 200 to about 5,000, are especially suitable. Polypropylene glycol with a molecular weight of from about 300 to about 2500 are especially preferred within the scope of the present invention. Polyether polyols, such as those obtained from the polymerization of tetrahydrofuran, are also suitable as the polyol component for the preparation of component A. The polyethers were obtained in a manner known to the person skilled in the art by the reaction of the initial compound having at least one hydrogen atom reactive with alkylene oxides, for example, ethylene oxide, propylene oxide, butylene oxide, styrene oxide, tetrahydrofuran or epichlorohydrin or mixtures of two or more of these. Suitable starting compounds are, for example, water, ethylene glycol, propylene glycol-1, 2 or -1.3, butylene glycol-1,4 or -1.3, hexanediol-1, 6, octandiol-1, 8, neopentylene glycol, 1, 4-hydroxymethylcyclohexane, 2-methyl-l, 3-propanediol, glycerin, trimethylolpropane, hexantriol-1, 2,6,6-butanediol-1,2,4, trimethylolethane, pentaerythritol, mannitol, sorbitol, methyl glycoside, sugar, phenol, isononylphenol, resorcinol, hydroquinone, 1,2,2- or 1,1,2-tris- (hydroxyphenyl) -ethane, ammonia, methylamine, ethylenediamine, tetramethylenediamine or hexamethylenediamine, triethanolamine, aniline, phenylenediamine, 2,4- and 2, 6 -diaminotoluol and polyphenylpolymethylenepolyamines as can be obtained by the condensation of aniline-formaldehyde. Also suitable for use as a polyol component are polyethers that are modified by polymers. Products of this type can be obtained, for example, in the manner in which styrene, acrylonitrile, vinyl acetate, esters of acrylic acid or esters of methacrylic acid or mixtures of two or more of them in the presence of polyethers are polymerized. As polyisocyanates for the preparation of component A, for example, ethylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate (HDI), cyclobutan-1,3-diisocyanate, cyclohexane-1,3 can be used. - and -1,4-diisocyanate as well as mixtures of two or more of them, l-isocyanato-3, 3, 5-trimethyl-5-isocyanatomethylcyclohexane (isophorone diisocyanate, IPDI), diisocyanate of 2, - and 2, 6-hexahydrotoluylene, hexahydro-1,3, or -1,4-phenylene diisocyanate, tetramethylxylylene diisocyanate (TMXDI), 1,3- and 1,4-phenylene diisocyanate, 2,4- or 2,6-diisocyanate toluylene, diphenylmethane-2,4-diisocyanate, diphenylmethane-2, 2'-diisocyanate or diphenylmethane-4,4'-diisocyanate or mixtures of two or more of the aforementioned diisocyanates. Also within the scope of the present invention, suitable polyisocyanates for the preparation of component A are trivalent or higher valence isocyanates such as those obtainable, for example, by the oligomerization of diisocyanates. Examples of these trivalent or higher valence polyisocyanates are the triisocyanurates of HDI or IPDI or their mixtures or their mixed triisocyanurates. Suitable monhydroxyvinyl ether are all monofunctional alcohols which have at least one vinyl ether group in the molecule. Especially preferred are compounds of the general formula I R 1 -CH = CR 2-0-Z-0H (I) Where R 1 and R 2 independently represent hydrogen and / or C 1 -C 8 alkyl radical, but radicals are especially preferred. alkyl C _.-. Preferably one of the two radicals represents hydrogen, since otherwise a generally undesired decrease in the polymerization rate of component A is observed. In a preferred embodiment R1 represents a methyl group and R2 represents hydrogen. In an especially preferred embodiment R1 and R2 represent hydrogen. Z represents a divalent radical derived from divalent alcohols. Z can be, for example, a divalent radical derived from the group of linear diols, for example ethylene glycol, propylene glycol-1,3, butylene glycol-1, 4. Likewise Z can be derived from the group of divalent diols such as, for example, propylene glycol-1, 2 or butylene glycol-2, 3, or from the group of polyalkylene glycols, for example diethylene glycol, triethylene glycol or their higher homologs. Particularly preferred monohydroxyvinyl ethers are 4-hydroxybutylvinylether, 4-hydroxymethylcyclohexylmethylvinylether 2-hydroxyethylvinylether, triethylene glycol monovinyl ether or diethylene glycol monovinyl ether, or mixtures of two or more of them. As component B the adhesive to be used according to the present invention contains a photoinitiator or a mixture of two or more photoinitiators. The photoinitiator can initiate the radiation-induced polymerization of vinyl ether groups. Photoinitiators that create Lewis or Brdnstedt acids under the effect of electromagnetic radiation are especially suitable., especially under the effect of light. As photoinitiators that create Lewis or Bronsted acids under the effect of light, it is possible to use, within the framework of the present invention, preferably onium compounds which form complexes or salts of ferrocene complexes. Basically all photosensitive aromatic sulfonium or iodonium salts are suitable for the light-induced initiation of the polymerization. Particularly suitable are trisarylsulfoniumhexafluoroantimonates, trisarylsulfoniumhexafluorophosphonates, such as those contained in the commercial products Cyracure® UVI-6974 and UVI-6990 (manufacturer: UCC, Danbury, United Kingdom), or bis (4,4'-di ethylbenzyl) ) iodoniotetra (pentafluorobenzyl) orate (UV CATA 200, manufacturer: Rhone-Poulenc, Saint-Fons, FR). Within the framework of the present invention, a photoinitiator selected from the group containing triarylsulfonium complex salts, complex diaryliodonium salts or complex ferrocene salts, or a mixture of two or more of them, is especially preferred as component B. The photoinitiator employed within the framework of the present invention can initiate a polymerization of component A after irradiation with light of a wavelength of about 100 to about 600 nm. In a preferred embodiment of the present invention initiation begins by irradiation with light of wavelength of about 150 to about 500 nm, preferably about 20 to about 480 nm. Optionally, the adhesive to be used according to the present invention may contain c) as component C a compound with at least one vinyl ether group having a molecular weight of less than about 400. It may eventually be desirable to decrease the viscosity of the adhesive to be used in accordance with the present invention without having to employ solvents difficult to remove. In these cases, the adhesive to be used according to the present invention has as components C a compound with at least one vinyl ether group and a molecular weight of less than about 400. While component C allows a lower viscosity of the adhesive, it is generally totally or at least almost totally bound in the cross-linked polymer during curing, corresponding to the concept of a "reactive diluent". If it is only desired to obtain a dilution effect, it is sufficient that as component C a mixture of two or more compounds with only one vinyl ether group is used. However, if crosslinking of the adhesive is to be influenced through component C, it is preferable that component C has at least partially at least one compound with at least two vinyl ether groups or a mixture of two or more compounds as the "crosslinking agent". of this type. For use as component C in the adhesives to be used according to the present invention are suitable, for example, hydroxybutylvinylether, triethyleneglycoldivinyl ether, cyclohexanedimethanol divinyl ether, propylene propylene carbonate ether (for example Rapi-Cure® PEPC, ISP Europe), dodecyl inylether, cyclohexanedimethanol monovinyl ether. , cyclohexyl vinyl ether, diethylene glycoliyl ether, 2-ethylhexyl inyl ether, dipropylene glycol divinyl ether, tripropylene glycol divinyl ether, hexandioldi inyl ether, octadecyl vinyl ether, butandiolivinyl ether, glycerin trivinyl ether, trimethylolpropantrivinyl ether, pentaeritetravinyl ether or higher vinyl ethers of alcohols with a higher valency or mixtures of two or more of them. Optionally, the adhesive to be used according to the present invention can contain d) as component D a compound of at least two OH groups. The component D can also, in a manner comparable to the behavior of component C, participate in the polymerization of component A, and be integrated into the crosslinked adhesive. The component D can play on the one hand the function of a "reactive diluent" to decrease the viscosity of the adhesive, and on the other hand play the role of a "reticulator". Compounds carrying suitable OH groups are for example ethylene glycol, diethylene glycol, neopentyl glycol, hexanediol, butanediol, propylene glycol, glycerin, trimethylolpropane, pentaerythritol, or sugar alcohols or a mixture of two or more of them, as well as oligomeric ethers of the compounds mentioned individual or oligomeric ethers made from a mixture of two or more of the mentioned compounds therebetween. Suitable examples are, for example, reaction products of polyfunctional alcohols such as glycerin, trimethylolethane and / or trimethylolpropane, pentaerythritol or sugar alcohols with the alkylene oxides mentioned for the formation of oligoether polyols with a molecular weight of approximately 16,000. Suitable for use as component D are high molecular weight compounds such as polyester polyols, polyether polyols, polyurethane polyols, polycarbonate polyols, polyvinylacet polyols, polyacrylate polyols, polymethacrylate polyols or copolyols made from suitable acrylates and methacrylates or mixtures of two or more of the aforementioned polyols. Preferably the compounds used as component D have a molecular weight of up to about 10,000, especially between about 500 and about 6,000. Within the framework of the present invention, it is especially preferred to use polyester polyols, polyether polyols or polyurethane polyols as component D. Polyester polyols which can be used as component D are preferably polyesters with a molecular weight (Mn) of more than about 400 to about 10,000. Preferred polyester polyols are prepared, for example, by the reaction of alcohols with low molecular weights, especially ethylene glycol, diethylene glycol, neopentyl glycol, hexanediol, butanediol, propylene glycol, glycerin or trimethylolpropane by condensation with a polycarboxylic acid or a mixture of two or more of these acids. For example, difunctional and / or trifunctional alcohols can be condensed in polyesters with dicarboxylic and / or tricarboxylic acids or their reactive derivatives. Suitable dicarboxylic acids are, for example, succinic acid and its higher homologues with up to 16 carbon atoms, in addition unsaturated dicarboxylic acids such as maleic acid, fumaric acid, and aromatic dicarboxylic acids, especially isomeric italic acids such as, for example, italic acid, isophthalic or terephthalic acid. Suitable tricarboxylic acids are, for example, citric acid or trimethyl acid. Also suitable are aliphatic polycarboxylic acids such as adipic acid, glutamic acid, pimelic acid, aromatic acids such as naphtalindicarboxylic acid, cycloalkyl acids such as cyclohexanedicarboxylic acid, or acids with a heteroatom content such as S or N, for example diglycolic acid, 2,2-dicarboxylic acid ethyl ether or thiodiglycolic acid. Also suitable as polyols for the preparation of the polyesters are aliphatic alcohols with two to four OH groups per molecule. The OH groups are preferably primary without, however, they may also be secondary. Suitable aliphatic alcohols include, for example, ethylene glycol, propylene glycol, butanediol-1,4, pentanediol-1,5, hexanediol-1,6,6-heptanediol-1,7,7-octanediol-1,8 and their higher homologues and isomers, as they are obtained in a manner known to the person skilled in the art through a progressive prolongation of the hydrocarbon chain each time in a CH2 group or with the introduction of amplifications in the carbon chain. Also suitable alcohols with higher functionality such as glycerin, trimethylolpropane, pentaerythritol, as well as oligomeric ethers of the said substances with themselves or in mixture from two or more of the ethers mentioned therebetween. In addition polyfunctional alcohols, of low molecular weight, products of the reaction can be used with alkylene oxides having up to four carbon atoms as polyol components for the preparation of the polyesters. Suitable, for example, are products of the reaction of ethylene glycol, propylene glycol, of the isomeric butanediols or of hexanediols with ethylene oxide, propylene oxide and / or butylene oxide. Furthermore, products of the reaction of polyfunctional alcohols such as glycerin, trimethylolethane and / or trimethylolpropane, pentaerythritol or sugar alcohols with the alkylene oxides mentioned for polyether polyols are also suitable. Furthermore, the products of the reaction of low molecular weight polyfunctional alcohols with alkylene oxides having up to four carbon atoms can be used as the polyol component for the production of the polyester. Suitable reaction products are, for example, ethylene glycol, propylene glycol, butanediols or isomeric hexanediols with ethylene oxide, propylene oxide and / or butylene oxide. In addition, the reaction products of polyfunctional alcohols, such as, for example, glycerin, trimethylolethane and / or trimethylolpropane, pentaerythritol or sugar alcohols with the alkylene oxides in polyester polyols are also suitable. Especially suitable as polyols for the production of polyesters are polyether polyols with a molecular weight of from about 100 to 5,000, preferably from about 200 to about 3,000. Especially preferred within the scope of the present invention is propylene glycol with a molecular weight of from about 300 to about 2,500. Polyester polyols are also suitable, such as are obtained, for example, by the polymerization of tetrahydrofuran. A group of polymers used as component D according to the present invention preferred within the framework of said invention are the polyurethane polyols. Polyurethane polyols are understood as compounds within the scope of the present invention that can be obtained by the polyaddition of divalent alcohols and / or alcohols with a higher valence and polyisocyanates. As polyols for the production of the polyurethanes, polyesters and / or polyethers with a molecular weight of about 300 to 10,000, preferably about 800 to about 5,000, and with at least two OH groups are typically chosen. As polyesters for the preparation of the polyurethanes which can be used within the framework of the present invention, all polyesters terminated in OH groups which can react with at least one difunctional isocyanate with chain elongation are suitable. Among these we can mention for example the aforementioned polyesters.

Dihydroxydicidal compounds which can be used as a representation of the polyol components which can be used for the preparation of the polyurethanes are, for example, butanediol-1,3-butanediol-1, butanediol-2,2,3-diethylpropan-1, 3 -diol, 2-methyl-2-propylpropan-1, 3-diol, isomeric octanediols, ethylenically unsaturated divalent compounds such as for example heptenediol, octenediol and also divalent compounds with a content of N or S heteroatoms, for example diethylene glycol, triethylene glycol, thioethylene glycol , diethanolamine or N-methyldiethanolamine, or mixtures of two or more of them. The diols react in general terms for the preparation of the polyurethanes with at least difunctional isocyanates. The isocyanates used within the framework of the present invention may be aliphatic or aromatic and may have from about 4 to about 40 carbon atoms. Examples of suitable isocyanates are hexamethylene diisocyanate (HDI), 1,8-octanediisocyanate, 1,10-decanediisocyanate, diisocyanates such as those obtained from fatty acid dimerization and corresponding functionalization, phenylene diisocyanate-1,4, 2,4- and 2,6-toluol-diisocyanate and mixtures thereof, 1,5-naphthylene diisocyanate, 2,2'-, 2,4'- or 4,4'-diphenylmethane diisocyanate (MDI) or mixtures of two or more of them , tetramethylxylylenediisocyanate (TMXDI), -isophorone diisocyanate (IPDI), cyclobutan-1,3-diisocyanate, cyclohexane-1,3- and -1, '4-diisocyanate, 2,4- and 2,6-hexahydrotoluylene diisocyanate, hexahydro- 1, 3- or -1,4-phenyldiisocyanate, 2,2'-diphenylmethane diisocyanate, or 4,4'-diphenylmethane diisocyanate or mixtures of two or more of the aforementioned diisocyanates. Furthermore, within the scope of the present invention, isocyanate can be used for the production of the polyurethane contained in component A, trivalent polyisocyanates or with a higher valence, such as, for example, by the oligomerization of diisocyanates. Examples of such trivalent polyisocyanates or with a higher valence are the triisocyanurates of HDI or IPDI or their mixed triisocyanurates. In general terms, the average molecular weight of the polymers used as component D is not less than 400. Since the polymers in general terms, according to the chosen synthesis method, present a statistical distribution of molecular weights, the concept "average molecular weight" "refers to the number (Mn) of molecular weight of the polymers contained in component A. This includes that it can also contain individual polymer molecules whose molecular weight is below the given value of 500. Likewise, the adhesive to be used according to the present invention, e) can contain as component E a compound with at least one epoxy group. Among the compounds which can be used as component E within the framework of the present invention, with at least one epoxy group are, for example, cycloaliphatic epoxides. Examples of cycloaliphatic epoxides are bis (3,4-epoxycyclohexylmethyl) oxalate, bis (3,4-epoxycyclohexylmethyl) adipate, bis (3,4-epoxy-6-methylcyclohexylmethyl) adipate and / or bis (3,4-epoxycyclohexylmethyl) ) pimelate. 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, such as, for example, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylic acid, 3,4-epoxy-1-methylcyclohexylmethyl-3, 4-epoxy acid, are also suitable. l-methylcyclohexanecarboxylic acid, 6-methyl-3,4-epoxycyclohexylmethyl-6-methyl-3, 4-epoxycyclohexanecarboxylic acid, 3,4-epoxy-2-methylcyclohexylmethyl-3,4-epoxy-2-methylcyclohexanecarboxylic acid, 3,4-epoxy-5-methyclohexylmethyl-3,4-epoxy-5-methylcyclohexanecarboxylic acid and the like. Additional suitable epoxides which can be used within the scope of the present invention include glycidyl ether, such as those obtainable from polyhydric phenols, such as, for example, diglycidyl, 2'-bis (2, 3-epoxypropoxyphenol) -propane. Component E contains, in general terms, at least about 5% by weight of a compound with only one epoxy group. The part of compounds with two or more epoxy groups is correspondingly between about 5 and about 50% by weight and the part of epoxides with three or more high functionality is between about 5 and about 30% by weight. In addition to the components A, B, C, D and E, the adhesive to be used according to the present invention may contain as component F in addition a compound or a mixture of two or more compounds having a polymerizable cationic functional group which is neither a vinyl ether group or an epoxy group. Examples are, for example, olefins, vinylarenes, especially styrene, and heterocyclic compounds, such as, for example, ethers, thioethers, esters or acetals. Styrene is preferred within the scope of the present invention. The adhesives to be used according to the present invention can also contain additives, among which we can mention accelerators, pigments, fillers, reinforcers, initiators, stabilizers, inhibitors or adhesion aids. Accelerators that accelerate the course of the polymerization are usually used. This can be carried out either by accelerating the initiation reaction due to the influence of radiation or by reinforcing the polymerization itself, i.e. the addition of individual monomers therebetween. The adhesive to be used according to the present invention may contain the components A, B as well as optionally C, D, E and / or F, as well as optionally available additives, in different quantitative ratios. All quantitative data refer to the complete adhesive. Component A corresponds in general terms to about 1% by weight to about 99.9% by weight of the adhesive, with a portion from about 1% by weight to about 99% by weight being preferred. Generally speaking, component B represents a portion from about 0.1 to about 8% by weight of the adhesive employed, with a portion from about 1% by weight to about 5% by weight, especially from about 2% by weight to about 4% being preferred. in weigh. Component C is used in the adhesive in an amount of up to about 40% by weight, with a part from about 5% by weight to about 30% by weight being preferred. Component D is used in an amount of up to about 40% by weight in the adhesive, with a portion from about 5% by weight to about 20% by weight being preferred. The component E is used in a part of up to about 40% by weight in the adhesive, with a part from about 10% by weight to about 30% by weight being preferred. The component F is used in a part of up to about 40% by weight in the adhesive, with a part from about 10% by weight to about 30% by weight being preferred. The additives which may optionally be used in the adhesive to be used according to the present invention can overall represent an amount of up to about 20% by weight. In a preferred embodiment of the present invention, an adhesive is used which contains approximately: - from 10 to 96% by weight of component A - from 2 to 4% by weight of component B and - from 2 to 30% by weight of component C. Also object of the present invention is an adhesive containing three components A, B and D, where a) as component A contains a polymeric compound with at least one vinyl ether group having a molecular weight of more than 400, b) as component B contains a photoinitiator which, after irradiation with light of a wavelength of 100 to 600 nm initiates a polymerization of component A, and c) as component D contains a compound having at least two OH groups.

In a further preferred embodiment the adhesive according to the present invention contains about - from 50 to 80% by weight of component A, - from 2 to 4% by weight of component B and - from 18 to 46% by weight of component D. Eventually the adhesive may also contain an additional component selected from components C, E and F as well as additives according to the definition within the framework of this document. The adhesive composition according to the present invention is usually made by mixing the mentioned components. The application on sheets to be bonded can be carried out by machines usually used for these purposes, for example, by means of conventional laminators. Especially suitable is the application of the adhesives in a liquid state on a sheet to be glued to form a laminated composite. The sheet receiving said adhesive l is then joined with an additional sheet by known techniques and finally brought to an irradiation zone where the polymerization reaction is initiated by irradiation with ultraviolet light, i.e. crosslinking of the individual components. Eventually the sheet receiving the adhesive l can also be irradiated before the bonding of the surface presenting adhesive with another sheet. This however implies that the joining of the two sheets is carried out at a time when the polymerization of the adhesive, ie its hardening, is still not complete. The adhesive must then be able to develop a bond that is still sufficient to allow the second sheet to be glued. This procedure is especially indicated when two sheets must be glued between them which do not allow the passage of the necessary irradiation to initiate the polymerization. The described gluing and laminating process can be repeated several times, such that the laminated article can consist of more than two bonded ls. Among the materials that can be adhered are for example paper, cellulose hydrate, plastics such as polyethylene, polypropylene, polyethylene terephthalate, polyvinyl chloride, copolymers of vinyl chloride and vinylidene chloride, copolymers of vinyl acetate / olefins, polyamides, or metallic sheets such as-for example, aluminum, lead or copper.

Claims (12)

1. CLAIMS 1. The use of an adhesive, containing at least two components A and B, for the production of composite film materials, where a) as component A contains a compound with at least one vinyl ether group, which has a higher molecular weight 400, and b) as component B contains a photoinitiator which, after irradiation with light of a wavelength of 100 to 600 nm, initiates the polymerization of component A.
2. 2. The use according to claim 1, characterized in that as a component B contains a photoinitiator chosen from the group containing triarylsulfonium complex salts, complex diaryliodonium salts and complex ferrocene salts.
3. The use according to claim 1 or according to claim 2, characterized in that the adhesive c) as component C contains a compound with at least one vinyl ether group having a lower molecular weight than
4. 400. The use according to one of claims 1 to 3, characterized in that the adhesive d) as component D contains a compound with at least two OH groups.
5. 5. The use according to claim 4, characterized in that as component D contains at least one trifunctional alcohol or a mixture of two or more trifunctional alcohols with a molecular weight of less than 400.
6. 6. The use according to claim 4, characterized as component D contains at least one difunctional alcohol or a mixture of two or more difunctional alcohols with a molecular weight of at least 400.
7. 7. The use according to any of claims 4 to 6, characterized in that as component D contains a alcohol selected from the group consisting of glycerin, triethylolpropane, trimethylolpropane or pentaerythritol, or a mixture of two or more of them.
8. 8. The use according to any of claims 4 to 6, characterized in that component D contains a compound selected from the group consisting of polyester polyols, polyether polyols, polycarbonate polyols, polyacetal polyols or polyurethane polyols.
9. The use according to one of claims 1 to 8, characterized in that the adhesive e) as component E contains a compound with at least one epoxy group.
10. 10. The use according to one of claims 1 to 9, characterized in that the adhesive contains - from 10 to 96% by weight of component A - from 2 to 4% by weight of component B and - from 2 to 30% by weight of component C.
11. 11. An adhesive containing three components A, B and D, wherein a) as component A contains a compound with at least one vinyl ether group having a molecular weight greater than 400, and b) as component B contains a photoinitiator which after irradiation with light of wavelength 100 to 600 nm initiates a polymerization of component A and c) as component D contains a compound having at least two OH groups. The adhesive according to claim 11, characterized in that it contains: from 50 to 80% by weight of component A, from 2 to 4% by weight of component B and from 18 to 46% by weight of component D.