JP5193816B2 - Composite film and method for producing the composite film - Google Patents

Description

  The present invention relates to a composite film and a method for producing the same, and more particularly to a composite film having high strength and high elongation at break and a method for producing the same.

  Composite films made of acrylic polymers and urethane polymers are disclosed in, for example, Japanese Patent Application Laid-Open Nos. 2003-96140, 2003-171411, 2004-10661, and 2004-10661. The composite film has good strength and elongation at break.

  Here, various polyols are used as a raw material for the urethane polymer, and for example, polyols such as polyether, polyester, and polycarbonate are used.

  By the way, if a polycarbonate polyol such as 1,6-hexanediol can be used as the polycarbonate polyol, it has excellent heat resistance, weather resistance, oil resistance, and chemical resistance due to the high cohesive strength of the polycarbonate group. A polyurethane is obtained. However, 1,6-hexanediol polycarbonate polyol has a problem of being difficult to handle because it has high crystallinity and is solid at room temperature. In addition, when such a highly crystalline polycarbonate polyol is used, the polycarbonate diol chain portion has a melting point even after conversion to a urethane polymer in an acrylic monomer, so the temperature is 50 ° C. or less. Crystals are formed. For this reason, separation occurs in the acrylic monomer or solidification occurs, so that there is a problem that it is difficult to form a film.

JP 2003-96140 A JP 2003-171411 A JP 2004-10661 A Japanese Patent Application Laid-Open No. 2004-10661

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a film having high strength and high elongation at break and a method for producing the film.

In the composite film of the present invention, a polycarbonate polyol and a diisocyanate are subjected to a polyaddition reaction in a monofunctional (meth) acrylic monomer to form a urethane polymer to produce a mixture of the urethane polymer and the monofunctional (meth) acrylic monomer. Then, a composite film obtained by addition polymerization of a monofunctional (meth) acrylic monomer, the polycarbonate polyol is a polycarbonate polyol which is liquid at 20 ° C., and the monofunctional (meth) acrylic monomer is the urethane It has a solubility parameter δ [(MPa) ^1/2 ] whose absolute value of the difference from the solubility parameter of the polymer is 6.4 [(MPa) ^1/2 ] or less.

  In the present invention, the polycarbonate polyol is a copolycarbonate diol obtained by copolymerizing 1,6-hexanediol with 1,4-butanediol, 1,5-pentanediol or 1,4-cyclohexanedimethanol. Preferably there is.

Moreover, the solubility parameter δ [(MPa) ^1/2 ] of the monofunctional (meth) acrylic monomer is 17.7 [(MPa) ^1/2 ] or more and 25.5 [(MPa) ^1/2 ] or less. Can be.

In the method for producing a composite film of the present invention, a polycarbonate polyol and a diisocyanate are subjected to a polyaddition reaction in a monofunctional (meth) acrylic monomer to form a urethane polymer to form a mixture of the urethane polymer and the monofunctional (meth) acrylic monomer. And then a step of addition polymerization of the monofunctional (meth) acrylic monomer to form an acrylic polymer to produce a composite film, wherein the polycarbonate polyol is a liquid polycarbonate at 20 ° C. The monofunctional (meth) acrylic monomer is a polyol, and the absolute value of the difference between the solubility parameter δ [(MPa) ^1/2 ] of the monofunctional (meth) acrylic monomer and the solubility parameter of the urethane polymer and wherein the but is 6.4 ^{[(MPa) 1/2]} or less That.

In the present invention, the solubility parameter δ of the monofunctional (meth) acrylic monomer may be 17.7 [(MPa) ^1/2 ] or more and 25.5 [(MPa) ^1/2 ] or less. .

  In the present invention, in the step of preparing the composite film, a mixture of the urethane polymer and the monofunctional (meth) acrylic monomer is applied on a support and irradiated with light to prepare an acrylic polymer. Can do.

According to the present invention, even when a polycarbonate polyol is used as a raw material for the urethane polymer, there is no difficulty in handling during the production process, and a film having good characteristics can be obtained.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in detail.
The composite film of the present invention forms a urethane polymer by polyaddition reaction of polycarbonate polyol and diisocyanate in a monofunctional (meth) acrylic monomer to produce a mixture of urethane polymer and monofunctional (meth) acrylic monomer. Thereafter, it is obtained by addition polymerization of a monofunctional (meth) acrylic monomer.

However, this polycarbonate polyol is a polycarbonate polyol that is liquid at 20 ° C., and the monofunctional (meth) acrylic monomer has an absolute value of a difference of 6. from the solubility parameter of the urethane polymer using polycarbonate polyol and diisocyanate. It has a solubility parameter δ [(MPa) ^1/2 ] that is 4 [(MPa) ^1/2 ] or less.

  Thus, if a urethane polymer is formed in a specific monofunctional (meth) acrylic monomer using a specific polycarbonate polyol and diisocyanate, it can be formed into a film without causing problems in handling. In other words, a composite film can be formed using polycarbonate polyol which can realize excellent properties as a raw material for urethane polymer, and can be separated and solidified at room temperature in a monofunctional (meth) acrylic monomer. And can be made into a film.

  Polycarbonate polyol that is liquid at 20 ° C. means that its melting point is 20 ° C. or less, and examples include polycarbonate polyol having a side chain, that is, having a branched structure, such as 2,2-dialkyl-1,3. -Polycarbonate diol which uses propanediol, 2,4-dialkyl-1,5-pentanediol and the like as a diol component.

  Other polycarbonate polyols include those obtained by reducing the crystallinity of 1,6-hexanediol polycarbonate polyol. For example, 1,6-hexanediol is an aliphatic diol having no side chain. And copolycarbonate diol copolymerized therewith. As such a copolycarbonate diol, for example, 1,6-hexanediol and an aliphatic diol such as 1,4-butanediol, 1,5-pentanediol, 1,4-cyclohexanedimethanol are copolymerized. At least one diol selected from the group consisting of copolycarbonate diol, 1,4-butanediol, 1,5-pentanediol and 1,6-hexanediol obtained by copolymerization with 1,3-propanediol. And copolycarbonate diol obtained by the above method.

  In the present invention, this polycarbonate polyol is a copolycarbonate diol obtained by copolymerizing 1,6-hexanediol and 1,4-butanediol, 1,5-pentanediol, or 1,4-cyclohexanedimethanol. Is preferably used.

  Examples of the copolycarbonate diol include trade names “T5650J”, “T5651”, “T5652”, “T4671”, “T4672”, or Ube Industries, Ltd., which are copolymer polycarbonate diols manufactured by Asahi Kasei Chemicals Corporation. Product names “UM-CARB90 (1/3)”, “UM-CARB90 (1/1)”, and the like are commercially available.

  In the present invention, the polycarbonate diol can be used alone or in combination of two or more.

  Examples of the diisocyanate used in the present invention include aromatic, aliphatic, and alicyclic diisocyanates. Examples of the diisocyanate preferably used include tolylene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, hydrogenated diphenylmethane diisocyanate, 1,5-naphthylene diisocyanate, 1,3. -Phenylene diisocyanate, 1,4-phenylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, cyclohexane-1,4-diisocyanate, dicyclohexylmethane-4,4-diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, methylcyclohexane diisocyanate m- tetramethylxylylene diisocyanate, and the like. These diisocyanates can be used alone or in combination of two or more.

  In the present invention, the amount of the polyol component and diisocyanate component used to form the urethane polymer is preferably NCO / OH (equivalent ratio) of 1.1 or more and 2.0 or less, preferably 1.12 or more, 1 Is more preferably 1.60 or less, and particularly preferably 1.15 or more and 1.35 or less. If the NCO / OH (equivalent ratio) is less than 1.1, the molecular weight of the urethane polymer becomes too large, and the viscosity of the urethane polymer-acrylic monomer mixture (syrup) becomes large, making it difficult to work in the subsequent sheeting process. In addition, the strength of the resulting composite film tends to decrease. Moreover, if NCO / OH (equivalent ratio) is 2.0 or less, the elongation and flexibility of the resulting composite film can be sufficiently secured.

  In general, a catalyst is used for the reaction between the hydroxyl group of the diol and the isocyanate. However, according to the present invention, the reaction is promoted without using an environmental load catalyst such as dibutyltin dilaurate or tin octoate. Can be made.

  In the present invention, examples of the monofunctional (meth) acrylic monomer include acrylic monomers such as acrylic acid, methacrylic acid, maleic acid, and crotonic acid, or methyl (meth) acrylate and ethyl (meth) acrylate, for example. , N-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate , Isopentyl (meth) acrylate, hexyl (meth) acrylate, cyclohexyl (meth) acrylate, heptyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) Acrylate, nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, undecyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate, Pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, heptadecyl (meth) acrylate, octadecyl (meth) acrylate, nonadecyl (meth) acrylate, eicosyl (meth) acrylate, isobornyl (meth) acrylate, 1-adamantyl (meth) acrylate, etc. Alkyl (meth) acrylate monomers, 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, (meth ) 4-hydroxybutyl acrylate, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate, (4 -Hydroxyl group-containing monomers such as hydroxymethylcyclohexyl) -methyl acrylate; Glycidyl group-containing monomers such as glycidyl (meth) acrylate and methyl glycidyl (meth) acrylate; Cyanoacrylate monomers such as acrylonitrile and methacrylonitrile; N, N- Dimethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N-isopropyl (meth) T) acrylamide, N-hydroxyethyl (meth) acrylamide, (meth) acryloylmorpholine, N-vinyl-2-piperidone, N-vinyl-3-morpholinone, N-vinyl-2-caprolactam, N-vinyl-2-pyrrolidone N-vinyl-1,3-oxazin-2-one, N-vinyl-3,5-morpholinedione, N-cyclohexylmaleimide, N-phenylmaleimide, N-acryloylpyrrolidine, t-butylaminoethyl (meth) acrylate And nitrogen-containing monomers such as vinyl acetate and styrene. These monofunctional (meth) acrylic monomers can be used alone or in combination of two or more.

  In the present invention, monofunctional (meth) acrylic monomers include acrylic monomers such as phenylethoxy acrylate, acrylic acid, methacrylic acid, maleic acid, and crotonic acid, or, for example, methyl (meth) acrylate, ethyl (meth) ) Acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, N , N-dimethylaminopropyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N-isopropyl (meth) acrylamide, N-hydroxyethyl (meth) acrylic Mido, (meth) acryloylmorpholine, N-vinyl-2-piperidone, N-vinyl-3-morpholinone, N-vinyl-2-caprolactam, N-vinyl-2-pyrrolidone, N-vinyl-1,3-oxazine- Use of nitrogen-containing monomers such as 2-one, N-vinyl-3,5-morpholinedione, N-cyclohexylmaleimide, N-phenylmaleimide, N-acryloylpyrrolidine, t-butylaminoethyl (meth) acrylate, etc. preferable.

However, in the present invention, the difference between the solubility parameter of the monofunctional (meth) acrylic monomer and the solubility parameter of the obtained urethane polymer is 6.4 [(MPa) ^1/2 ] or less in absolute value. The monofunctional (meth) acrylic monomer is selected so as to satisfy this condition. Here, the solubility parameter of the monofunctional (meth) acrylic monomer is the solubility parameter of the monofunctional (meth) acrylic monomer that contributes to the formation of the urethane polymer. For example, a plurality of monofunctional (meth) acrylic monomers In the case of contributing to the reaction, all of these are involved in the numerical value of the solubility parameter. However, the monofunctional (meth) acrylic monomer added after the reaction, that is, after the urethane polymer formation, is added to the numerical value of the solubility parameter. Do not add to calculation. The solubility parameter of the monofunctional (meth) acrylic monomer used in the present invention is preferably 17.7 [(MPa) ^1/2 ] or more and 25.5 [(MPa) ^1/2 ] or less. If it exists in this range, compatibility with a urethane polymer can be improved.

In the present invention, the term “film” includes a sheet, and the term “sheet” includes a film.
In the present invention, when “(meth) acryl” is displayed, such as (meth) acrylate and (meth) acrylic acid, it means acrylic and / or methacrylic. In addition, when the same expression is used in the present invention, it has the same meaning as described above unless otherwise specified. Furthermore, even when “acrylic” is simply displayed, there is no particular notice, and if there is no problem in general common sense, it will be understood to include methacryl.

  In addition, other polyfunctional monomers can be added within a range that does not impair the characteristics. Examples of the polyfunctional monomer include 1,4-butanediol diacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol diacrylate, 1,9-nonanediol diacrylate, 2-n-butyl- 2-ethyl-1,3-propanediol diacrylate, tripropylenediol diacrylate, tetraethylenediol diacrylate, neopentyldiol diacrylate, neopentyldiol dimethacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, tris ( 2-acryloyloxyethyl) isocyanurate, pentaerythritol tetraacrylate and the like. Among these, trimethylolpropane tri (meth) acrylate is preferable.

  The polyfunctional monomer can be added in an amount of 1 part by weight or more and 20 parts by weight or less based on 100 parts by weight of the total amount of the monofunctional (meth) acrylic monomer. If the content of the polyfunctional monomer is 1 part by weight or more, the cohesive force of the composite film is sufficient, and if it is 20 parts by weight or less, the elastic modulus does not become too high, and the unevenness of the adherend surface is reduced. Can follow.

  In the present invention, the urethane polymer does not contain a crosslinked structure. The diol used for forming the urethane polymer is preferably a linear (linear) diol. However, the diol may be a side chain diol or a diol containing a branched structure as long as the condition that the urethane polymer does not form a crosslinked structure is satisfied.

The composite film of the present invention is firstly mixed in a mixture containing a monofunctional (meth) acrylic monomer whose absolute value of the difference from the solubility parameter of the urethane polymer is 6.4 [(MPa) ^1/2 ] or less at room temperature. A liquid polycarbonate polyol and diisocyanate are subjected to a polyaddition reaction to form a urethane polymer, thereby producing a urethane polymer-acrylic monomer mixture (syrup). Thereafter, if necessary, a photopolymerization initiator, an ultraviolet absorber, a light stabilizer, and the like are added and irradiated with ultraviolet rays to produce a composite film.

  In the reaction between the polycarbonate polyol and the diisocyanate, the reaction temperature and reaction time can be appropriately set. For example, the inner bath temperature is preferably 20 ° C. or higher and 90 ° C. or lower, more preferably 40 ° C. It is not lower than 80 ° C. and particularly preferably not lower than 50 ° C. and not higher than 75 ° C. The reaction time is preferably 1 hour or more and 48 hours or less, more preferably 3 hours or more and 24 hours or less, and particularly preferably 5 hours or more and 15 hours or less.

  Various photopolymerization initiators can be used as the photopolymerization initiator used here. For example, ketal photopolymerization initiators, α-hydroxyketone photopolymerization initiators, α-aminoketone photopolymerization initiators can be used. Polymerization initiator, acylphosphine oxide photopolymerization initiator, bezophenone photopolymerization initiator, thioxanthone photopolymerization initiator, benzoin ether photopolymerization initiator, acetophenone photopolymerization initiator, aromatic sulfonyl chloride photopolymerization initiator Agents, photoactive oxime photopolymerization initiators, benzoin photopolymerization initiators, benzyl photopolymerization initiators, and the like can be used.

  Examples of the ketal photopolymerization initiator include 2,2-dimethoxy-1,2-diphenylethane-1-one (for example, “Irgacure 651” manufactured by Ciba Specialty Chemicals Co., Ltd.). Etc.).

  Examples of the α-hydroxyketone photopolymerization initiator include 1-hydroxycyclohexyl phenyl ketone (commercially available products such as “Irgacure 184” manufactured by Ciba Specialty Chemicals), 2-hydroxy- 2-methyl-1-phenylpropan-1-one (commercially available products such as “Darocur 1173” manufactured by Ciba Specialty Chemicals), 1- [4- (2-hydroxyethoxy)- Phenyl] -2-hydroxy-2-methyl-1-propan-1-one (commercially available products such as “Irgacure 2959” manufactured by Ciba Specialty Chemicals) and the like.

  As the α-aminoketone photopolymerization initiator, for example, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one (commercially available is Ciba “Irgacure 907” manufactured by Specialty Chemicals Co., Ltd.), 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1 (commercially available products include Ciba Specialty Chemicals "Irgacure 369" etc.).

  Examples of the acylphosphine oxide-based photopolymerization initiator include 2,4,6-trimethylbenzoyldiphenylphosphine oxide (commercially available products such as “Lucirin TPO” manufactured by BASF).

  Examples of the benzoin ether photopolymerization initiator include benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isopropyl ether, benzoin isobutyl ether, 2,2-dimethoxy-1,2-diphenylethane-1-one, and anisole. And methyl ether.

  Examples of the acetophenone photopolymerization initiator include 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 1-hydroxycyclohexyl phenyl ketone, 4-phenoxydichloroacetophenone, and 4- (t-butyl). Examples include dichloroacetophenone.

  Examples of the aromatic sulfonyl chloride photopolymerization initiator include 2-naphthalenesulfonyl chloride, and examples of the photoactive oxime photopolymerization initiator include 1-phenyl-1,1-propanedione-2- (O-ethoxycarbonyl) -oxime and the like.

  Examples of the benzoin photopolymerization initiator include benzoin, and examples of the benzyl photopolymerization initiator include benzyl.

  Examples of the benzophenone photopolymerization initiator include benzophenone, benzoylbenzoic acid, 3,3′-dimethyl-4-methoxybenzophenone, polyvinylbenzophenone, α-hydroxycyclohexyl phenyl ketone, and the like.

  Examples of the thioxanthone photopolymerization initiator include thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-diisopropylthioxanthone, dodecylthioxanthone, and the like.

Examples of the ultraviolet absorber (UVA) used in the present invention include 2- (2-hydroxy-5-tert-butylphenyl) -2H-benzotriazole (commercially available) as a benzotriazole ultraviolet absorber. Examples include “TINUVIN PS” manufactured by Ciba Japan Ltd.), benzenepropanoic acid and 3- (2H-benzotriazol-2-yl) -5- (1,1-dimethylethyl) -4-hydroxy (C ester compounds with a side chain and straight chain alkyl) of ₇ -C ₉ (as the ones commercially available, manufactured by Ciba Japan K.K. "TINUVIN 384-2", etc.), octyl -3- [3-tert -Butyl-4-hydroxy-5- (5-chloro-2H-benzotriazol-2-yl) phenyl] propionate and 2-ethylhexyl A mixture with -3- [3-tert-butyl-4-hydroxy-5- (5-chloro-2H-benzotriazol-2-yl) phenyl] propionate (commercially available, Ciba Japan “TINUVIN 109”, etc.), 2- (2H-benzotriazol-2-yl) -4,6-bis (1-methyl-1-phenylethyl) phenol (commercially available, “TINUVIN 900” manufactured by Japan Ltd.), 2- (2H-benzotriazol-2-yl) -6- (1-methyl-1-phenylethyl) -4- (1,1,3,3-tetramethyl) Butyl) phenol (as commercially available products such as “TINUVIN 928” manufactured by Ciba Japan), methyl-3- (3- (2H-benzotriazole-2) -Yl) -5-tert-butyl-4-hydroxyphenyl) propionate / polyethylene glycol 300 reaction product (as commercially available, “TINUVIN 1130” manufactured by Ciba Japan Co., Ltd.), 2- ( 2H-benzotriazol-2-yl) -p-cresol (as commercially available “TINUVIN P” manufactured by Ciba Japan), 2- [5-chloro (2H) -benzotriazole-2 -Yl] -4-methyl-6- (tert-butyl) phenol (commercially available, "TINUVIN 326" manufactured by Ciba Japan), 2- (2H-benzotriazol-2-yl ) -4,6-di-tert-pentylphenol (as a commercially available product, “TINU manufactured by Ciba Japan Ltd.) IN 328 "), 2- (2H-benzotriazol-2-yl) -4- (1,1,3,3-tetramethylbutyl) phenol (commercially available, manufactured by Ciba Japan Co., Ltd.) “TINUVIN 329”, etc.) of 2-2′-methylenebis [6- (2H-benzotriazol-2-yl) -4- (1,1,3,3-tetramethylbutyl) phenol] (commercially available) As possible, “TINUVIN 360” manufactured by Ciba Japan Ltd.), methyl-3- (3- (2H-benzotriazol-2-yl) -5-tert-butyl-4-hydroxyphenyl) propionate and polyethylene Reaction product with glycol 300 (such as “TINUVIN 213” manufactured by Ciba Japan as commercially available product), 2- (2H-benzoto Riazol-2-yl) -6-dodecyl-4-methylphenol (such as “TINUVIN 571” manufactured by Ciba Japan as commercially available), 2- [2-hydroxy-3- (3, 4,5,6-tetrahydrophthalimido-methyl) -5-methylphenyl] benzotriazole (as commercially available, “Sumisorb 250” manufactured by Sumitomo Chemical Co., Ltd.), 2,2′-methylenebis [6- (Benzotriazol-2-yl) -4-tert-octylphenol] (as commercially available products such as “ADKSTAB LA31” manufactured by ADEKA), hydroxyphenyltriazine (HPT) -based and benzotriazole (BTZ) -based ultraviolet rays Absorbent (as commercially available, “TINUVIN 5236” manufactured by Ciba Japan, etc. ), “TINUVIN 234” manufactured by Ciba Japan.

  Moreover, as a commercially available hydroxyphenyl triazine type ultraviolet absorber, for example, 2- (4,6-bis (2,4-dimethylphenyl) -1,3,5-triazin-2-yl)- Reaction product of 5-hydroxyphenyl and [(C10-C16, mainly C12-C13 alkyloxy) methyl] oxirane (as commercially available, “TINUVIN 400” manufactured by Ciba Japan, etc.), Reaction product of 2- (2,4-dihydroxyphenyl) -4,6-bis- (2,4-dimethylphenyl) -1,3,5-triazine and (2-ethylhexyl) -glycidic acid ester (commercial) As a commercially available product, “TINUVIN 405” manufactured by Ciba Japan Co., Ltd.), 2,4-bis [2-hydroxy-4-butoxyphenyl]- 6- (2,4-dibutoxyphenyl) -1,3,5-triazine (as commercially available, “TINUBIN 460” manufactured by Ciba Japan), 2- (4,6-diphenyl) -1,3,5-triazin-2-yl) -5-[(hexyl) oxy] -phenol (such as commercially available “TINUVIN 1577” manufactured by Ciba Japan), 2- ( 2-hydroxy-4- [1-octyloxycarbonylethoxy] phenyl) -4,6-bis (4-phenylphenyl) -1,3,5-triazine (as commercially available, Ciba Japan “TINUVIN 479”, etc.).

Examples of commercially available benzophenone ultraviolet absorbers include “CHIMASSORB 81” manufactured by Ciba Japan. Examples of the benzoate UV absorber include “TINUVIN 120” manufactured by Ciba Japan as 2,4-di-tert-butylphenyl-3,5-di-tert-butyl-4-hydroxybenzoate. Can be mentioned.
In this invention, the said ultraviolet absorber can be used individually or in combination of 2 or more types.

  The light stabilizer used in the present invention is preferably a hindered amine light stabilizer (HALS).

As a commercially available hindered amine light stabilizer, for example, as a light stabilizer which is a polymer of dimethyl succinate and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol, TINUVIN 622 "(manufactured by Ciba Japan), a polymer of dimethyl succinate and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol and N, N ', N", N''' -Tetrakis- (4,6-bis- (butyl- (N-methyl-2,2,6,6-tetramethylpiperidin-4-yl) amino) -triazin-2-yl) -4,7- As a light stabilizer which is a one-to-one reaction product with diazadecane-1,10-diamine, “TINUVIN 119” (manufactured by Ciba Japan), dibutylamine, 1,3-triazine, N, N′-bis ( , 2,6,6-Tetramethyl-4-piperidyl-1,6-hexamethylenediamine and N- (2,2,6,6-tetramethyl-4-piperidyl) butylamine As the agent, “TINUVIN 2020” (manufactured by Ciba Japan), poly [{6- (1,1,3,3-tetramethylbutyl) amino-1,3,5-triazine-2,4-diyl} {2 , 2,6,6-Tetramethyl-4-piperidyl} imino] hexamethylene {(2,6,6-tetramethyl-4-piperidyl) imino}) as a light stabilizer, “TINUVIN 944” (Ciba Japan)), photostability that is a mixture of bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate and methyl 1,2,2,6,6-pentamethyl-4-piperidyl sebacate Agent and "TINUVIN 765" (manufactured by Ciba Japan), "TINUVIN 770" (manufactured by Ciba Japan), decane as a light stabilizer that is bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate As a light stabilizer which is a reaction product of diacid bis (2,2,6,6-tetramethyl-1- (octyloxy) -4-piperidinyl) ester (1,1-dimethylethyl hydroperoxide) and octane “TINUVIN 123” (manufactured by Ciba Japan), bis (1,2,2,6,6-pentamethyl-4-piperidyl) [[3,5-bis (1,1-dimethylethyl) -4-hydroxyphenyl ] [TINUVIN 144] (manufactured by Ciba Japan) as light stabilizer which is methyl] butyl malonate, cyclohexane and N-butyl peroxide 2,2,6 “TINUVIN 152” is a light stabilizer that is a reaction product of 6-tetramethyl-4-piperidineamine-2,4,6-trichloro-1,3,5-triazine and 2-aminoethanol. (Ciba Japan), mixture of bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate and methyl-1,2,2,6,6-pentamethyl-4-piperidyl sebacate “TINUVIN 292” (manufactured by Ciba Japan), “TINUVIN 5100” (manufactured by Ciba Japan), and “CHIMASSORB 119FL” (Ciba Japan) as a high-molecular-weight type hindered amine light stabilizer. ), “CHIMASSORB 2020FDL” (manufactured by Ciba Japan), “CHIMASSORB 944 “DL” (manufactured by Ciba Japan), “TINUVIN 622LD” (manufactured by Ciba Japan), “TINUVIN 111FDL” (manufactured by Ciba Japan), “TINUVIN 783FDL” (Ciba) as blend type hindered amine light stabilizers・ Japan), “TINUVIN 791FB” (Ciba Japan), blend type of UV absorber and light stabilizer, “TINUVIN 5050” (Ciba Japan), “TINUVIN 5060” (Ciba Japan), “TINUVIN 5151” (manufactured by Ciba Japan), and the like.
In the present invention, the above hindered amine light stabilizers can be used alone or in combination of two or more.

  If necessary, the composite film is added with commonly used additives such as anti-aging agents, fillers, pigments, colorants, flame retardants, antistatic agents and the like within a range that does not impair the effects of the present invention. be able to. These additives are used in normal amounts depending on the type. These additives may be added in advance before the polymerization reaction between the diisocyanate and the polycarbonate polyol, or may be added before the urethane polymer and the acrylic monomer are respectively polymerized.

  In the present invention, a small amount of solvent may be added to adjust the viscosity of the coating. The solvent can be appropriately selected from commonly used solvents, and examples thereof include ethyl acetate, toluene, chloroform, dimethylformamide and the like.

  In the present invention, the composite film is prepared by, for example, applying a urethane polymer-acrylic monomer mixture (syrup) on a support (exfoliated if necessary) or the like, and depending on the type of the photopolymerization initiator. , Α-rays, β-rays, γ-rays, ionizing radiation such as neutrons and electron beams, radiation such as ultraviolet rays, curing with visible light, etc., and then peeling and removing the support etc. Can be formed. Or it can also obtain in the form by which the composite film was laminated | stacked on the support body etc., without peeling and removing a support body etc.

  Specifically, after the polycarbonate polyol is dissolved in the monofunctional (meth) acrylic monomer, the viscosity is adjusted by adding diisocyanate or the like and reacting with the polyol, and this is applied to the support or the like, or as necessary. The composite film can be obtained by coating the release-treated surface of the support and the like and then curing it using a low-pressure mercury lamp or the like. In this method, the monofunctional (meth) acrylic monomer may be added at a time during urethane synthesis, or may be added in several divided portions. Alternatively, the polyol may be reacted after the diisocyanate is dissolved in the monofunctional (meth) acrylic monomer. According to this method, the molecular weight is not limited and a high molecular weight polyurethane can be produced, so that the molecular weight of the finally obtained urethane can be designed to an arbitrary size.

  At this time, in order to avoid polymerization inhibition due to oxygen, a release sheet (separator, etc.) may be placed on the mixture coated on the substrate sheet, etc. to block oxygen, or filled with an inert gas. The oxygen concentration may be lowered by placing a substrate in the container.

  In the present invention, the type of radiation and the type of lamp used for irradiation can be selected as appropriate, such as a low-pressure lamp such as a fluorescent chemical lamp, a black light and a sterilization lamp, a high-pressure such as a metal halide lamp and a high-pressure mercury lamp. A lamp or the like can be used.

Irradiation amounts such as ultraviolet rays can be arbitrarily set according to required film characteristics. Generally, the dose of ultraviolet rays, 100~5,000mJ / cm ^2, preferably not 1,000~4,000mJ / cm ^2, more preferably a 2,000~3,000mJ / cm ^2. When the irradiation amount of ultraviolet rays is less than 100 mJ / cm ² , a sufficient polymerization rate may not be obtained, and when it is more than 5,000 mJ / cm ² , deterioration may be caused.

  In addition, the temperature at the time of irradiation with ultraviolet rays or the like is not particularly limited and can be arbitrarily set. However, if the temperature is too high, a termination reaction due to polymerization heat is likely to occur, which may cause deterioration of characteristics. The temperature is usually 70 ° C. or lower, preferably 50 ° C. or lower, more preferably 30 ° C. or lower.

  The thickness of the composite film of the present invention can be appropriately selected according to the purpose and the like, for example, according to the type and location of the object to be covered and protected, and is not particularly limited, but may be 50 μm or more and 1 mm or less. Preferably, it is 100 μm or more and 500 μm or more, more preferably 150 μm or more and 400 μm or less.

  In the present invention, the weight ratio of the acrylic polymer to the urethane polymer in the composite film is preferably in the range of acrylic polymer / urethane polymer = 1/99 to 80/20. If the acrylic polymer content ratio is less than 1/99, the viscosity of the mixed solution for forming a composite film (urethane polymer-acrylic monomer syrup) may increase, and workability may deteriorate. In some cases, flexibility and strength as a film cannot be obtained.

  The composite film of the present invention preferably has a breaking strength in a tensile test of 10 MPa or more and 100 MPa or less, more preferably 15 MPa or more and 80 MPa or less, and particularly preferably 20 MPa or more and 60 MPa or less. However, the conditions of the tensile test are that the width of the test piece is 10 mm, the length is 130 mm, the grip distance is 50 mm, and the tensile speed is 200 mm / min. If the breaking strength of the composite film is less than 10 MPa, the composite film tends to be flexible. On the other hand, if the breaking strength exceeds 100 MPa, the composite film may become too rigid.

The composite film of the present invention has high strength and the like, and is excellent in flexibility with respect to a curved surface. Furthermore, the composite film of the present invention is also excellent in weather resistance. Therefore, it is suitable as a protective sheet for protecting painted surfaces of automobiles, aircrafts, and the like.

  EXAMPLES The present invention will be described in detail below using examples, but the present invention is not limited to these. In the following examples, unless otherwise specified, parts mean parts by weight and% means% by weight. The measurement methods and evaluation methods used in the following examples are shown below.

(Measurement method and evaluation method)
(1) Evaluation of syrup state The urethane polymer-acrylic monomer mixture (syrup) was observed with the naked eye and evaluated based on the following evaluation criteria.
Evaluation criteria:
A Transparent state B Turbid state C Urethane polymer and acrylic monomer separated

(2) Breaking elongation and breaking strength A test sample was prepared by cutting out a size of 1 cm wide × 13 cm long from the film. The support was removed from the test sample and a tensile test was performed. That is, a tensile test was performed in an atmosphere of room temperature (23 ° C.) and relative humidity (50%) at a tensile speed of 200 mm / min and a distance between chucks of 50 mm. From the obtained stress-strain curve, 100% modulus, breaking elongation (breaking elongation) and breaking strength were determined.

Example 1
<< Preparation of coating solution for composite film >>
In a reaction vessel equipped with a condenser, a thermometer, and a stirrer, 45 parts of n-butyl acrylate (BA), 15 parts of isobornyl acrylate (IBXA) as a monofunctional (meth) acrylic monomer, polyol Copolycarbonate diol (PCDL) obtained by copolymerizing 1,6-hexanediol having a number average molecular weight of 2,000 with 1,5-pentanediol (trade name “T5652” manufactured by Asahi Kasei Corporation, melting point 35.5 parts of -5 ° C. or less) and 0.008 part of dibutyltin dilaurate as a catalyst were added, and 4.5 parts of hydrogenated xylylene diisocyanate (HXDI) was added dropwise with stirring, at 65 ° C. for 6 hours. It was made to react and the urethane polymer-acrylic-type monomer mixture (syrup) was obtained.

  Thereafter, 3 parts of acrylic acid (AA) and 2,2-dimethoxy-1,2-diphenylethane-1-one (“IRGACURE 651” manufactured by Ciba Specialty Chemicals Co., Ltd.) as a photopolymerization initiator are 0. .18 parts were added to obtain a composite film coating solution.

Note that the solubility parameter δ of the monofunctional (meth) acrylic monomer excluding post-added acrylic acid is 18.01 [(MPa) ^1/2 ], and the solubility parameter of the urethane polymer is 24.37 [(MPa). ) ^1/2 ]. Therefore, the difference between the solubility parameter of the monofunctional (meth) acrylic monomer and the urethane polymer was 6.36 [(MPa) ^1/2 ] in absolute value. Moreover, the usage-amount of the polyisocyanate component and the polyol component was NCO / OH = 1.25 by equivalent ratio.

<Production of composite film>
The prepared coating solution for composite film was applied on a polyethylene terephthalate (PET) film (thickness 38 μm) subjected to a release treatment as a support so that the thickness after curing was 100 μm. A PET film peel-treated as a separator is stacked thereon, and this PET film surface is cured by irradiating with ultraviolet rays (illuminance: 290 mW / cm ² , light amount: 4,600 mJ / cm ² ) using a metal halide lamp. A composite film was formed on the substrate. Thereafter, the coated PET film (separator) was removed and dried at 140 ° C. for 3 minutes to remove unreacted residual acrylic monomer to obtain a composite film (with a support).

<Measurement and evaluation>
The obtained syrup and composite film were observed (evaluated) in a syrup state, and measured and evaluated for breaking elongation and breaking strength. The results are shown in Table 1.

(Example 2)
In a reaction vessel equipped with a condenser, a thermometer, and a stirrer, 14.375 parts isobornyl acrylate (IBXA) and 43.125 parts phenylethoxy acrylate (PhEA) as a monofunctional (meth) acrylic monomer. Copolycarbonate diol (PCDL) obtained by copolymerizing 1,6-hexanediol having a number average molecular weight of 800 with 1,5-pentanediol as a polyol (trade name “T5650J” manufactured by Asahi Kasei Corporation, melting point 32.5 parts of -5 ° C or lower) and 0.0085 part of dibutyltin dilaurate as a catalyst, and 10 parts of xylylene diisocyanate (XDI) were added dropwise with stirring and reacted at 65 ° C for 6 hours. A urethane polymer-acrylic monomer mixture (syrup) was obtained.

  Thereafter, 2.875 parts of acrylic acid (AA) and 2,2-dimethoxy-1,2-diphenylethane-1-one (“IRGACURE 651” manufactured by Ciba Specialty Chemicals) as a photopolymerization initiator Was added to obtain a coating solution for a composite film.

The solubility parameter δ of the monofunctional (meth) acrylic monomer excluding post-added acrylic acid is 20.23 [(MPa) ^1/2 ], and the solubility parameter of the urethane polymer is 26.11 [(MPa). ) ^1/2 ]. Therefore, the difference between the solubility parameter of the monofunctional (meth) acrylic monomer and the urethane polymer was 5.88 [(MPa) ^1/2 ] in absolute value. Moreover, the usage-amount of the polyisocyanate component and the polyol component was NCO / OH = 1.25 by equivalent ratio.

  A composite film was produced in the same manner as in Example 1 by using the obtained composite film coating solution. About the obtained syrup and composite film, the same measurement and evaluation as Example 1 were performed. The results are shown in Table 1.

(Example 3)
In a reaction vessel equipped with a condenser, a thermometer, and a stirrer, as a monofunctional (meth) acrylic monomer, 10 parts of acrylic acid (AA), 20 parts of acrylolylmorpholine (ACMO), acrylic acid n- Copolycarbonate diol (PCDL) obtained by copolymerization of 1,6-hexanediol having a number average molecular weight of 800 with 1,5-pentanediol using 20 parts of butyl (BA) as a polyol (product of Asahi Kasei Corporation) 38 parts of "T5650J", melting point of -5 ° C or lower) was added, and 12 parts of hydrogenated xylylene diisocyanate (HXDI) was added dropwise with stirring and reacted at 65 ° C for 6 hours, urethane polymer-acrylic A monomer mixture (syrup) was obtained.

  Thereafter, 0.25 part of bis (2,4,6-trimethylbenzoyl) phenyl-phosphine oxide (“IRGACURE 819” manufactured by Ciba Specialty Chemicals Co., Ltd.) as a photopolymerization initiator was added to form a composite film. A coating solution was obtained.

The solubility parameter δ of the monofunctional (meth) acrylic monomer is 21.10 [(MPa) ^1/2 ], and the solubility parameter of the urethane polymer is 24.20 [(MPa) ^1/2 ]. Therefore, the difference between the solubility parameter of the monofunctional (meth) acrylic monomer and the urethane polymer was 3.10 [(MPa) ^1/2 ] in absolute value. Moreover, the usage-amount of the polyisocyanate component and the polyol component was NCO / OH = 1.25 by equivalent ratio.

  A composite film was produced in the same manner as in Example 1 by using the obtained composite film coating solution. About the obtained syrup and composite film, the same measurement and evaluation as Example 1 were performed. The results are shown in Table 1.

Example 4
As a monofunctional (meth) acrylic monomer, 12 parts of acrylic acid (AA), 48 parts of n-butyl acrylate (BA) and polyol as a monofunctional (meth) acrylic monomer in a reaction vessel equipped with a condenser, a thermometer, and a stirring device, Copolycarbonate diol (PCDL) obtained by copolymerizing 1,6-hexanediol having a number average molecular weight of 800 with 1,5-pentanediol (trade name “T5650J” manufactured by Asahi Kasei Corporation, melting point of −5 ° C. or less ) 30.4 parts, while stirring, 9.6 parts of hydrogenated xylylene diisocyanate (HXDI) was added dropwise and reacted at 65 ° C. for 6 hours to obtain a urethane polymer-acrylic monomer mixture (syrup). Obtained.

  Thereafter, 0.18 part of bis (2,4,6-trimethylbenzoyl) phenyl-phosphine oxide (“IRGACURE 819” manufactured by Ciba Specialty Chemicals Co., Ltd.) as a photopolymerization initiator was added, and the composite film A coating solution was obtained.

The solubility parameter δ of the monofunctional (meth) acrylic monomer is 19.47 [(MPa) ^1/2 ], and the solubility parameter of the urethane polymer is 24.20 [(MPa) ^1/2 ]. Therefore, the difference between the solubility parameter of the acrylic monomer and the urethane polymer was 4.73 [(MPa) ^1/2 ] in absolute value. Moreover, the usage-amount of the polyisocyanate component and the polyol component was NCO / OH = 1.25 by equivalent ratio.

  A composite film was produced in the same manner as in Example 1 by using the obtained composite film coating solution. About the obtained syrup and composite film, the same measurement and evaluation as Example 1 were performed. The results are shown in Table 1.

(Comparative Example 1)
In a reaction vessel equipped with a condenser, a thermometer, and a stirrer, 70 parts of 2-ethylhexyl acrylate (2-EHA) as an acrylic monomer and 1,6-hexanediol having a number average molecular weight of 800 as a polyol are used. 25.7 parts of copolycarbonate diol (PCDL) obtained by copolymerization with 1,5-pentanediol (trade name “T5650J” manufactured by Asahi Kasei Co., Ltd., melting point of −5 ° C. or lower) and dibutyltin dilaurate as a catalyst Then, 4.3 parts of xylylene diisocyanate (XDI) is added dropwise with stirring and reacted at 65 ° C. for 6 hours to obtain a urethane polymer-acrylic monomer mixture (syrup). Thus, a composite film coating solution was prepared.

The solubility parameter δ of the acrylic monomer is 17.63 [(MPa) ^1/2 ], and the solubility parameter of the urethane polymer is 24.13 [(MPa) ^1/2 ]. Therefore, the difference between the solubility parameter of the acrylic monomer and the urethane polymer was 6.50 [(MPa) ^1/2 ] in absolute value. Moreover, the usage-amount of the polyisocyanate component and the polyol component was NCO / OH = 0.67 in an equivalent ratio.

  A composite film was produced in the same manner as in Example 1 using the obtained acrylic monomer-urethane polymer mixture (coating liquid for composite film). About the obtained syrup and composite film, the same measurement and evaluation as Example 1 were performed. The results are shown in Table 2.

(Comparative Example 2)
In a reaction vessel equipped with a condenser, a thermometer, and a stirrer, 70 parts of 2-ethylhexyl acrylate (2-EHA) as an acrylic monomer and poly (hexamethylene carbonate) having a number average molecular weight of 1,000 as a polyol ) 26.5 parts of glycol (manufactured by Asahi Kasei Chemicals Co., Ltd., PHC) (solid at 20 ° C.) and 0.007 part of dibutyltin dilaurate as a catalyst were added, and while stirring, hydrogenated xylylene diisocyanate (HXDI) 3.5 parts was dropped and reacted at 65 ° C. for 6 hours to obtain a urethane polymer-acrylic monomer mixture (syrup) to prepare a coating solution for a composite film.

The solubility parameter δ of the acrylic monomer is 17.63 [(MPa) ^1/2 ], and the solubility parameter of the urethane polymer is 22.81 [(MPa) ^1/2 ]. Therefore, the difference between the solubility parameter of the acrylic monomer and the urethane polymer was 5.18 [(MPa) ^1/2 ] in absolute value. Moreover, the usage-amount of the polyisocyanate component and the polyol component was NCO / OH = 0.67 in an equivalent ratio.

  A composite film was produced in the same manner as in Example 1 using the obtained acrylic monomer-urethane polymer. About the obtained syrup and composite film, the same measurement and evaluation as Example 1 were performed. The results are shown in Table 2.

(Comparative Example 3)
In a reaction vessel equipped with a condenser, a thermometer and a stirrer, 70 parts of hydroxyethyl acrylate (HEA) as an acrylic monomer and poly (hexamethylene carbonate) glycol (Asahi Kasei) with a number average molecular weight of 1,000 as a polyol 26.5 parts of PHC (made by Chemicals Co., Ltd.) (solid at 20 ° C.) and 0.007 part of dibutyltin dilaurate as a catalyst were added and 3.5 parts of hydrogenated xylylene diisocyanate (HXDI) with stirring. Was dropped at 65 ° C. for 6 hours to obtain a urethane polymer-acrylic monomer mixture (syrup) to prepare a coating solution for a composite film.

The solubility parameter δ of the acrylic monomer is 25.47 [(MPa) ^1/2 ], and the solubility parameter of the urethane polymer is 22.81 [(MPa) ^1/2 ]. Therefore, the absolute value of the difference between the solubility parameter of the acrylic monomer and the urethane polymer was 2.66 [(MPa) ^1/2 ]. Moreover, the usage-amount of the polyisocyanate component and the polyol component was NCO / OH = 0.67 in an equivalent ratio.

  A composite film was produced in the same manner as in Example 1 using the obtained acrylic monomer-urethane polymer mixture (coating liquid for composite film). About the obtained syrup and composite film, the same measurement and evaluation as Example 1 were performed. The results are shown in Table 2.

(Comparative Example 4)
In a reaction vessel equipped with a condenser, a thermometer and a stirrer, 12 parts of acrylic acid (AA), 48 parts of n-butyl acrylate (BA) as an acrylic monomer, poly (oxytetramethylene) as a polyol ) 29.2 parts of glycol (PTMG) ("PTMG650" manufactured by Mitsubishi Chemical Corporation, solid at 20 ° C) was added, and 10.8 parts of hydrogenated xylylene diisocyanate (HXDI) was added dropwise with stirring. The mixture was reacted at 65 ° C. for 6 hours to obtain 26.5 parts of a urethane polymer-acrylic monomer mixture (syrup) and 0.007 part of dibutyltin dilaurate as a catalyst. 3.5 parts of HXDI) was dropped and reacted at 65 ° C. for 6 hours to obtain a urethane polymer-acrylic monomer mixture (siroc ), Which was prepared coating fluid for composite film.

The solubility parameter δ of the acrylic monomer is 19.47 [(MPa) ^1/2 ], and the solubility parameter of the urethane polymer is 21.57 [(MPa) ^1/2 ]. Therefore, the absolute value of the difference between the solubility parameter of the acrylic monomer and the urethane polymer was 2.10 [(MPa) ^1/2 ]. Moreover, the usage-amount of the polyisocyanate component and the polyol component was NCO / OH = 1.25 by equivalent ratio.

  A composite film was produced in the same manner as in Example 1 using the obtained acrylic monomer-urethane polymer mixture (coating liquid for composite film). About the obtained syrup and composite film, the same measurement and evaluation as Example 1 were performed. The results are shown in Table 2.

(Comparative Example 5)
In a reaction vessel equipped with a condenser, a thermometer, and a stirrer, 12 parts of acrylic acid (AA), 48 parts of n-butyl acrylate (BA) as an acrylic monomer, and poly (ethylene adipate) as a polyol 33.5 parts of glycol (PEA) (trade name “Nipporan 4002” manufactured by Nippon Polyurethane Industry Co., Ltd., solid at 20 ° C.) was added and stirred, and 6.5 g of hydrogenated xylylene diisocyanate (HXDI). Part was dropped and reacted at 65 ° C. for 6 hours to obtain a urethane polymer-acrylic monomer mixture (syrup) to prepare a coating solution for a composite film.

The solubility parameter δ of the acrylic monomer is 19.47 [(MPa) ^1/2 ], and the solubility parameter of the urethane polymer is 19.25 [(MPa) ^1/2 ]. Therefore, the absolute value of the difference between the solubility parameter of the acrylic monomer and the urethane polymer was 0.22 [(MPa) ^1/2 ]. Moreover, the usage-amount of the polyisocyanate component and the polyol component was NCO / OH = 1.25 by equivalent ratio.

  A composite film was produced in the same manner as in Example 1 using the obtained acrylic monomer-urethane polymer mixture (coating liquid for composite film). About the obtained syrup and composite film, the same measurement and evaluation as Example 1 were performed. The results are shown in Table 2.

  As is clear from Table 1, the syrup states of Examples 1 to 4 were evaluation criteria B or higher, and the urethane polymer and the acrylic monomer were not separated. Moreover, it was excellent also in evaluation of breaking strength and breaking elongation, and had high strength and high breaking elongation.

On the other hand, in Comparative Example 1 where the difference in solubility parameter was larger than 6.5 (MPa) ^1/2 , the syrup was in a state where the acrylic monomer and the urethane polymer were separated, and a film could not be formed. In Comparative Examples 2 and 3 using PHC that was solid at 20 ° C., the syrup was in a state where the acrylic monomer and the urethane polymer were separated, and a film could not be formed. In Comparative Examples 4 and 5 in which no polycarbonate polyol was used, either the elongation at break or the strength at break was insufficient.

  The composite film of the present invention is a film having high strength and high elongation at break, and can be suitably used as a film that requires these physical properties. Further, the composite film of the present invention is excellent in heat resistance, weather resistance, flexibility and the like. For example, even if it is used outdoors for a long time, the mechanical properties are not deteriorated, so that it is exposed to the outdoor weather. It can be used in places where

Claims (5)

Polycarbonate polyol and diisocyanate are subjected to polyaddition reaction in a monofunctional (meth) acrylic monomer to form a urethane polymer to produce a mixture of urethane polymer and monofunctional (meth) acrylic monomer, and then monofunctional (meta ) A composite film obtained by addition polymerization of an acrylic monomer, wherein the polycarbonate polyol is a polycarbonate polyol that is liquid at 20 ° C., and the polycarbonate polyol comprises 1,6-hexanediol, 1,4-butanediol, It is a copolycarbonate diol obtained by copolymerization with 1,5-pentanediol or 1,4-cyclohexanedimethanol, and the monofunctional (meth) acrylic monomer is different from the solubility parameter of the urethane polymer. Absolute value is 6. Composite film characterized in that it has a ^{[(MPa) 1/2]} or less is the solubility parameter δ ^{[(MPa) 1/2].} The solubility parameter δ [(MPa) ^1/2 ] of the monofunctional (meth) acrylic monomer is 17.7 [(MPa) ^1/2 ] or more and 25.5 [(MPa) ^1/2 ] or less. The composite film according to claim 1 . A step of polyaddition reaction of polycarbonate polyol and diisocyanate in a monofunctional (meth) acrylic monomer to form a urethane polymer to produce a mixture of urethane polymer and monofunctional (meth) acrylic monomer;
Next, the step of addition polymerization of the monofunctional (meth) acrylic monomer to form an acrylic polymer to produce a composite film,
The polycarbonate polyol is a polycarbonate polyol which is liquid at 20 ° C. , and the polycarbonate polyol is 1,6-hexanediol, 1,4-butanediol, 1,5-pentanediol or 1,4-cyclohexanedimethanol. A copolycarbonate diol obtained by copolymerization with
The monofunctional (meth) acrylic monomer has an absolute value of a difference of 6.4 between the solubility parameter δ [(MPa) ^1/2 ] of the monofunctional (meth) acrylic monomer and the solubility parameter of the urethane polymer. [(MPa) ^1/2 ] or less, A method for producing a composite film, The solubility parameter of the monofunctional (meth) acrylic monomer δ is, 17.7 ^{[(MPa) 1/2]} or more, 25.5 ^{[(MPa) 1/2]} claim 3, wherein the less is A method for producing the composite film described in 1. The step of producing the composite film is characterized in that a mixture of the urethane polymer and the monofunctional (meth) acrylic monomer is applied onto a support and irradiated with light to produce an acrylic polymer. 5. The method for producing a composite film according to any one of 3 and 4 .