JP2009154296A - Resin sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin sheet which is excellent in designability and high temperature molding processability and is free from peeling. <P>SOLUTION: In the resin sheet, a resin film A is laminated on a resin film B through an adhesive layer or a pressure-sensitive adhesive layer. The peel strength at 90° of an adhesive part is at least 0.3 kg/cm. The difference between a haze value before heating and a haze value after heating at 150°C for 30 min is 3% or below. The elongation in the longitudinal direction and/or in the width direction at 100°C is at least 100%. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a resin sheet in which at least two types of resin films are laminated via an adhesive layer or an adhesive layer. More specifically, the present invention relates to a decorative material having high design properties such as glossiness and depth, such as a member that requires moldability and a decorative member, such as a decorative material for automobiles and mobile phones.

  A resin sheet in which at least two types of resin films are laminated via an adhesive layer or a pressure-sensitive adhesive layer is used in various fields such as food packaging, cosmetic packaging, speaker members, and design films. (For example, see Patent Documents 1 to 3). In particular, a resin sheet obtained by laminating a plurality of types of films with an adhesive or the like is often used in order to improve functionality. These resin sheets are also particularly designed and can be used in molding applications. Laminate metal vapor-deposited foil with a resin sheet, and heat with a support substrate resin layer to improve moldability. A molding laminated sheet is used (for example, see Patent Document 4). In addition, a film that selectively reflects a specific wavelength by utilizing a light interference phenomenon that occurs by alternately laminating resin layers having different refractive indexes at a layer thickness of the wavelength level of light (for example, patent documents) 5 and 6) are also known, and are used for decorative materials such as cosmetics, cars, and mobile phones.

However, the resin sheet using the metal-deposited foil has a problem that the adhesive strength is low and peeling occurs at the time of stretching, and the stretchability of the metal-deposited night is poor and the molding is difficult. In addition, a film reflecting a specific wavelength has a limited film thickness due to optical design, has poor handling at the time of molding, and is difficult to be deep drawn.
Japanese Patent Laid-Open No. 2007-160709 Japanese Patent Laid-Open No. 2007-031661 Japanese Unexamined Patent Publication No. 2007-020139 Japanese Patent Laid-Open No. 2007-190702 Japanese Patent Laid-Open No. 3-41401 Japanese Patent Laid-Open No. 9-506837

  An object of the present invention is to provide a resin sheet that is excellent in design properties and high-temperature molding processability, and that does not peel off on an adhesive surface, in view of the above-described problems of the prior art.

  In order to solve the above problems, the resin sheet of the present invention is a resin sheet in which a resin film A and a resin film B are laminated via an adhesive layer or a pressure-sensitive adhesive layer, and a 90 ° peel strength at the adhesive part. 0.3 kg / cm or more, the difference between the haze value before the heat treatment and the haze value after the heat treatment for 30 minutes in an atmosphere of 150 ° C. is 3% or less, and the longitudinal direction at 100 ° C. and / or Alternatively, the elongation in the width direction is 100% or more.

  The resin sheet of the present invention is a resin sheet in which a resin film A and a resin film B are laminated via an adhesive layer or a pressure-sensitive adhesive layer, and the 90 ° peel strength at the adhesive part is 0.3 kg / cm or more The difference between the haze value before heat treatment and the haze value after heat treatment for 30 minutes in an atmosphere at 150 ° C. is 3% or less, and the elongation in the longitudinal direction and / or the width direction at 100 ° C. is 100 % Or more, it is possible to provide a resin sheet that does not peel at the bonding interface, hardly peels off at the trimming section after molding, has excellent designability, and good moldability. .

  In addition, the resin film A and / or the resin film B were alternately laminated with 50 layers or more of layers (X layer) mainly composed of the thermoplastic resin X and layers (Y layer) mainly composed of the thermoplastic resin Y. By setting it as a resin film, it is possible to provide a resin sheet that is excellent in design and gloss and has good electromagnetic wave permeability.

  Below, the actual form of this invention is demonstrated in detail.

  The resin sheet of the present invention is a resin sheet in which a resin film A and a resin film B are laminated via an adhesive layer or an adhesive layer, and the 90 ° peel strength at the adhesive part is 0.3 kg / cm or more. The difference between the haze value before the heat treatment and the haze value after the heat treatment for 30 minutes in an atmosphere at 150 ° C. is 3% or less, and the elongation in the longitudinal direction and / or the width direction at 100 ° C. is 100% or more. Need to be. Such a resin sheet hardly peels off at the adhesion interface, does not peel off at the trimming section after molding, has excellent design properties, and has excellent moldability.

  The resin used for the resin film of the present invention is not particularly limited, but a thermoplastic resin is preferable because of the ease of producing a laminated film and the ease of film formation.

  Examples of thermoplastic resins include polyolefin resins such as polyethylene, polypropylene, polystyrene, and polymethylpentene, alicyclic polyolefin resins, polyamide resins such as nylon 6 and nylon 66, aramid resins, polyethylene terephthalate, polybutylene terephthalate, polypropylene terephthalate, Polybutyl succinate, polyester resin such as polyethylene-2,6-naphthalate, polycarbonate resin, polyarylate resin, polyacetal resin, polyphenylene sulfide resin, tetrafluoroethylene resin, trifluorinated ethylene resin, trifluorinated ethylene chloride resin, Fluoropolymers such as tetrafluoroethylene-6fluoropropylene copolymer / vinylidene fluoride resin, acrylic resin, methacrylic resin, polyacetal resin , Polyglycolic acid resins, polylactic acid resins, and the like. Among these, polyester is particularly preferable from the viewpoint of strength, heat resistance, and transparency. Further, these thermoplastic resins may be homo resins, copolymerized or blends of two or more. Also, in each thermoplastic resin, various additives such as antioxidants, antistatic agents, crystal nucleating agents, inorganic particles, organic particles, thickeners, thermal stabilizers, lubricants, infrared absorbers, ultraviolet absorbers. An agent, a dopant for adjusting the refractive index, and the like may be added.

  Here, the polyester means a homopolyester or a copolyester that is a polycondensate of a dicarboxylic acid component skeleton and a diol component skeleton. Typical examples of the homopolyester include polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyethylene-2,6-naphthalate, poly-1,4-cyclohexanedimethylene terephthalate, and polyethylene diphenylate. In particular, polyethylene terephthalate is preferable because it is inexpensive and can be used in a wide variety of applications.

  The copolyester of the present invention is preferably a polycondensate comprising at least three or more components selected from the following dicarboxylic acid component skeleton and diol component skeleton. Examples of the dicarboxylic acid skeleton component include terephthalic acid, isophthalic acid, phthalic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 4,4′-diphenyldicarboxylic acid, 4 4,4'-diphenylsulfone dicarboxylic acid, adipic acid, sebacic acid, dimer acid, cyclohexanedicarboxylic acid and ester derivatives thereof. Examples of the glycol skeleton component include ethylene glycol, 1,2-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentadiol, diethylene glycol, polyalkylene glycol, and 2,2-bis (4 '-Β-hydroxyethoxyphenyl) propane, isosorbate, 1,4-cyclohexanedimethanol, spiroglycol and the like.

  Moreover, about the X layer and Y layer said by this invention, it is preferable that an in-plane average refractive index difference is 0.03 or more. More preferably, it is 0.05 or more, More preferably, it is 0.1 or more. When the difference in refractive index is smaller than 0.03, a sufficient reflectance cannot be obtained, which is not preferable. In order to achieve this, the resin of the Y layer is preferably amorphous. In this case, it is preferable because the orientation of the Y layer is relaxed by the heat treatment in the tenter and the in-plane average refractive index difference is further increased.

  As a preferred combination of the thermoplastic resin X and the thermoplastic resin Y in the present invention, the absolute value of the difference in SP value between the resin X and the resin Y is preferably 1.0 or less. In this case, delamination hardly occurs. More preferably, the layer made of the resin X and the layer made of the resin Y contain the same basic skeleton. The basic skeleton here is a repeating unit constituting the resin. For example, when one resin is polyethylene terephthalate, ethylene terephthalate is the basic skeleton. If the resin X and the resin Y are resins containing the same basic skeleton, peeling between layers is less likely to occur.

  As described above, in the laminated film of the present invention, it is preferable that the thermoplastic resin X is polyethylene terephthalate and the thermoplastic resin Y is a polyester containing spiroglycol. The polyester comprising spiroglycol refers to a copolyester copolymerized with spiroglycol, a homopolyester, or a polyester blended with them. Polyesters containing spiroglycol are preferred because they have a small glass transition temperature difference from polyethylene terephthalate or polyethylene naphthalate, so that they are not easily stretched at the time of molding and are also difficult to delaminate. More preferably, the thermoplastic resin X is polyethylene terephthalate or polyethylene naphthalate, and the thermoplastic resin Y is a polyester comprising spiroglycol and cyclohexanedicarboxylic acid. If the thermoplastic resin Y is a polyester comprising spiroglycol and cyclohexanedicarboxylic acid, the difference in the in-plane refractive index from polyethylene terephthalate or polyethylene naphthalate is increased, so that high reflectance can be easily obtained. Further, since the glass transition temperature difference between polyethylene terephthalate and polyethylene naphthalate is small, it is difficult to be over-stretched during molding, and is also difficult to delaminate.

  The resin sheet of the present invention needs to have a 90 ° peel strength at the adhesive part of 0.3 kg / cm or more. Preferably it is 1.0 kg / cm, More preferably, it is 1.5 kg / cm or more. When the peel strength is less than 0.3 kg / cm, it is not preferable because sufficient adhesion cannot be obtained and the film may be peeled off during stretching or forming. It is preferable that the adhesive strength is 1.5 kg / cm or more because peeling does not occur even in stretching, molding, trimming steps after molding, and the design can be maintained.

Examples of the adhesive used in the present invention include conventional phenol resin adhesives, resorcinol resin adhesives, phenol-resorcinol resin adhesives, epoxy resin adhesives, urea resin adhesives, urethane resin adhesives, Thermosetting resin adhesives such as polyurethane resin adhesives, polyester urethane resin adhesives and polyaromatic adhesives; reactive adhesives using ethylene-unsaturated carboxylic acid copolymers; vinyl acetate resins , Acrylic resin, ethylene vinyl acetate resin, polyvinyl alcohol, polyvinyl acetal, vinyl chloride resin, nylon, cyanoacrylate resin and other thermoplastic resin adhesives; chloroprene adhesives, nitrile rubber adhesives, SBR adhesives, natural Examples thereof include rubber adhesives such as rubber adhesives. It is also possible to provide a pressure-sensitive adhesive layer in place of the adhesive layer. As pressure-sensitive adhesives constituting the pressure-sensitive adhesive layer, acrylic pressure-sensitive adhesives, rubber-based pressure-sensitive adhesives, polyalkyl silicon-based pressure-sensitive adhesives, urethane-based pressure-sensitive adhesives And polyester-based pressure-sensitive adhesives.
In particular, in the present invention, a polyester urethane resin-based adhesive, a urethane resin-based adhesive, and an acrylic pressure-sensitive adhesive are preferable from the viewpoint of adhesion to a resin film, stretching, and followability during molding.

  It is cured by combining and reacting a polyol having a hydroxyl group at the terminal and a polyisocyanate, or a urethane prepolymer having an isocyanate group at the terminal and a polyol, which is formed of either a polyester urethane resin or a urethane resin. It functions as an adhesive or a pressure-sensitive adhesive. As the polyol, polyether polyol, polyester polyol, and other polyols can be used. For example, examples of the polyether polyol include polyoxyethylene polyol, polyoxypropylene polyol, polyoxyethylene-propylene copolymer polyol, polytetramethylene polyol, and the like alone or a mixture thereof. Polyester polyols include dicarboxylic acids (such as adipic acid, succinic acid, maleic acid, and phthalic acid) and glycols (such as ethylene glycol, propylene glycol, 1,4-butylene glycol, 1,6-hexane glycol, and neopentyl glycol). Polyols such as polyethylene adipate, polybutylene adipate, polyhexamethylene adipate, polypropylene adipate, polyethylene-propylene adipate, and the like, and polylactone polyols such as polycaprolactone polyol alone or A mixture thereof, polycarbonate polyol and the like can be mentioned.

Polyisocyanates include 2,4-tolylene diisocyanate, noble diisocyanate, 2,6-tolylene diisocyanate, 4,4-diphenylmethane diisocyanate, polymethylene polyphenylene polyisocyanate, carbodiimide-modified MDI, naphthalene diisocyanate and the like. Examples include isocyanate, hexamethylene diisocyanate, isophorone diisocyanate, 4,4-dicyclohexylmethane diisocyanate, and alicyclic polyisocyanate. The above polyisocyanates can be used alone or as a mixture thereof.
In the present invention, the acrylic pressure-sensitive adhesive may be a product obtained by copolymerizing a vinyl monomer having an alkyl group as a main component city and various vinyl monomers having a functional group. For example, alkyl acrylate, alkyl methacrylate (alkyl group and methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, t-butyl group, 2-ethylhexyl group, lauryl group, stearyl group, cyclohexyl group , Phenyl group, benzyl group, phenylethyl group, etc.), hydroxy group-containing monomers such as 2-hydroxy acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, acrylamide, methacrylamide, N- Methyl acrylamide, N-methyl methacrylamide, N-methylol acrylamide, N-methylol methacrylamide, N, N-dimethylol acrylamide, N-methoxymethyl acrylamide, N- Amide group-containing monomers such as toximethylmethacrylamide and N-phenylacrylamide, amino group-containing monomers such as N, N-diethylaminoethyl acrylate and N, N-diethylaminoethyl methacrylate, amino group-containing monomers such as glycidyl acrylate and glycidyl methacrylate, A carboxyl group such as acrylic acid, methacrylic acid and salts thereof (lithium salt, sodium salt, potassium salt, etc.) or a monomer containing the salt thereof can be used. Using one or two or more of these monomers Copolymerized. In addition, they can be copolymerized with a wide variety of monomers.
Examples of the various monomers include sulfonic acid groups such as epoxy group-containing monomers such as acrylic glycidyl ether, styrene sulfonic acid, vinyl sulfonic acid, and salts thereof (lithium salt, sodium salt, potassium salt, ammonium salt, etc.) Monomers containing a carboxyl group such as a monomer containing a salt, crotonic acid, itaconic acid, maleic acid, fumaric acid and salts thereof (lithium salt, sodium salt, potassium salt, ammonium salt, etc.), or maleic anhydride , Monomers containing acid anhydrides such as itaconic anhydride, vinyl isocyanate, allyl isocyanate, styrene, vinyl methyl ether, vinyl trisalkoxysilane, alkyl maleic acid monoester, alkyl fumaric acid monoester, acryloni Lil, methacrylonitrile, alkyl itaconic acid monoester, vinylidene chloride, vinyl acetate, etc. can be used vinyl chloride.

  Further, a modified acrylic copolymer, for example, a block copolymer modified with polyester, urethane, epoxy or the like, a graft copolymer, and the like are also possible.

  As a crosslinking agent used in the present invention, for example, when an acrylic resin containing a hydroxyl group or a carboxyl group is used, it is preferable to use a polyepoxide compound or a polyisocyanate compound as a crosslinking agent. Polyepoxide compounds include sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglocerol polyglycidyl ether, triglycidyl-tris (2-hydroxyethyl) isocyanurate, glycerol polyglycidyl ether, trimethylol Propane polyglycidyl ether, resorching glycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, bisphenol-S-diglycidyl ether, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether An ether etc. can be mentioned. Examples of the polyisocyanate compound include toluylene diisocyanate, 2,4-toluylene diisocyanate dimer, naphthylene-1,5-diisocyanate, o-toluylene diisocyanate, diphenylmethane diisocyanate, triphenylmethane triisocyanate, tris- (p-isocyanate). Phenyl) thiophosphite, polymethylene polyphenyl isocyanate, hexamethylene diisocyanate, trimethylhexanemethylene diisocyanate, isophorone diisocyanate, trimethylhexamethylene diisocyanate and the like. In addition, melamine-based crosslinking agents, isocyanate-based crosslinking agents, aziridine-based crosslinking agents, epoxy-based crosslinking agents, methylolized or alkylolized urea-based, acrylamide-based, polyamide-based resins, various silane coupling agents, various titanate-based cups A ring agent or the like can be used.

  In the adhesive layer and pressure-sensitive adhesive layer of the present invention, various additives such as a viscosity modifier, a leveling agent, an anti-gelling agent, an antioxidant, a heat-resistant stabilizer, a light-resistant stabilizer, an ultraviolet absorber, and a lubricant Pigments, dyes, organic or fine particles, fillers, antistatic agents, nucleating agents, and the like may be blended.

  The diluent used for adjusting the coating liquid of the adhesive and pressure-sensitive adhesive of the present invention includes a mixed solvent of one or more low-boiling solvents having a boiling point of 120 ° C. or lower and a high-boiling solvent having a boiling point higher than that of the low-boiling solvent. Can be used. Here, the reason why the temperature is set to 120 ° C. or less is that it is necessary to evaporate as quickly as possible at a drying temperature of 130 ° C. or less considering the heat resistance of the base sheet. Furthermore, it is preferable to use a high boiling point solvent having a boiling point which is at least 40 ° C. or higher, more preferably 40 ° C. or higher and 80 ° C. or lower than the highest boiling point solvent among the low boiling point solvents. The high boiling point solvent functions to prevent the coating surface from solidifying and promote other low boiling point evaporation. Moreover, it also has the function of suppressing the increase in the viscosity of the coating liquid during coating and improving the coating property. Specific examples of the low boiling point solvent include hydrocarbon solvents such as toluene, normal hexane, cyclohexane, methylcyclohexane, normal heptane and the like, and ketone solvents include acetone, methyl ethyl ketone (MEK), methyl Examples thereof include isobutyl ketone (MIBK). Examples of ester solvents include methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, and isobutyl acetate. Examples of ether solvents include 1,4-dioxane. Etc. Preferably, it is at least one solvent selected from toluene, methyl ethyl ketone, methyl isobutyl ketone, methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, and isobutyl acetate. In contrast, high-boiling solvents include methyl butyl ketone, diacetone alcohol, cyclohexanone, methyl cyclohexanone, cyclohexanol, methyl cyclohexanol, butyl acetate, pentyl acetate, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono Examples thereof include butyl ether, ethylene glycol monomethyl ether acetate, and ethylene glycol monoethyl ether acetate. Preferably, it is one solvent selected from methyl butyl ketone, cyclohexanone, methyl cyclohexanone, cyclohexanol, methyl cyclohexanol, butyl acetate, pentyl acetate, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, and ethylene glycol monobutyl ether. . Further, the content of the high boiling point solvent in the diluted solvent is 5 to 20% by weight, more preferably 7 to 15% by weight. When the amount is less than 5% by weight, the effect of promoting the evaporation of the low-boiling solvent is not sufficient. When the amount exceeds 20% by weight, the high-boiling solvent itself is not completely removed from the coating film and may remain in the coating film. Because there is sex.

  Further, the difference between the haze value before the heat treatment and the haze value after the heat treatment for 30 minutes in an atmosphere at 150 ° C. needs to be 3% or less. More preferably, it is 1% or less. When the difference in haze value is 1% or less, there is almost no change in appearance after molding, and a molded article having excellent design properties is obtained.

  In the resin sheet of the present invention, the elongation in the longitudinal direction or the width direction at 100 ° C. must be 100% or more. More preferably, it is 150% or more. When the elongation in an atmosphere of 100 ° C. is 150% or more, since the moldability is good, the resin sheet is suitable for vacuum forming, vacuum / pressure forming, ultra-high pressure forming, press forming, and insert forming.

  In the resin sheet of the present invention, the resin film A and / or the resin film B are alternately composed of 50 layers (X layer) composed mainly of the thermoplastic resin X and 50 layers (Y layer) composed mainly of the thermoplastic resin Y. Preferably, the color difference (ΔEab) is 10 or less before heating and after heating for 30 minutes in a 90 ° C. atmosphere. In such a case, a resin sheet having a design property is obtained, and an excellent molded body having no appearance change after molding is obtained, which is preferable.

  In the resin film A and / or the resin film B of the present invention, 50 layers or more of layers having the thermoplastic resin X as a main component (X layer) and thermoplastic resin Y as a main component (Y layer) are alternately laminated. A resin film is defined as having a portion having a structure in which an X layer and a Y layer are regularly laminated in the thickness direction. That is, it is preferable that the arrangement order in the thickness direction of the X layer and the Y layer in the film of the present invention is not in a random state, and the arrangement order of the third layer or more other than the X layer and the Y layer is as follows. It is not particularly limited. In addition, in the case of having a Z layer composed of an X layer, a Y layer, and a thermoplastic resin Z, they are laminated in a regular permutation such as X (YZX) n, X (YZYX) n, X (YXYZYX) n. Is more preferable. Here, n is the number of repetitive units. For example, when X = (YZX) n, where n = 3, it indicates that the layers are stacked in a permutation of XYZXYZXYZX in the thickness direction.

  In addition, the resin film A and / or the resin film B of the present invention have a total of 50 or more layers alternately laminated with a layer made of the thermoplastic resin X (X layer) and a layer made of the thermoplastic resin Y (Y layer). Is preferred. More preferably, it is 200 layers or more, More preferably, it is 500 layers or more. Unless a structure in which a total of 50 or more A layers and B layers are stacked is included, it is difficult to obtain a band having a reflectance of 30% or more. When 200 layers or more are stacked, the reflection band can be widened. Further, when it is 500 layers or more, it becomes easier to have a reflectance of 50% or more in a wide reflection band of 300 to 600 nm, and a laminated film having a metallic appearance by setting this reflection wavelength in the visible region. Can be obtained. Further, the upper limit is not particularly limited, but it is preferably 5000 layers or less in consideration of a decrease in wavelength selectivity due to a decrease in stacking accuracy due to an increase in the size of the device and an increase in the number of layers. .

  It is preferable that the color difference (ΔEab) before heating of the resin film A and / or resin film B of the present invention and after heating in a 90 ° C. atmosphere for 30 minutes is 10 or less. More preferably, it is 5 or less, More preferably, it is 3 or less. When ΔEab is larger than 10, it is not preferable because a change in color tone can be easily confirmed visually. When the color difference is 3 or less, the change in color tone is hardly noticed visually, and it is preferable because the design can be maintained even when stretching, molding, and printing are performed.

The resin sheet of the present invention is preferably heat-treated for 60 seconds in an atmosphere at 230 ° C., and then the amount of foreign matter deposited after heat treatment for 240 hours in an atmosphere at 90 ° C. is preferably 30 pieces / mm ² or less. When it is more than 30 / mm ² , the design property and the flatness of the resin sheet are impaired, which is not preferable. The number is preferably 10 pieces / mm ² or less, more preferably 0 pieces / mm ² . In this case, even if a resin sheet that has been subjected to vacuum forming, pressure forming, or vacuum / pressure forming is used in a place where heat resistance is required, such as a car interior decoration material, it is preferable because it can maintain design properties that are not related to the initial stage. . Here, the foreign matter having a size of 1 μm or more means that the maximum diameter is 1 μm or more.

In the resin sheet of the present invention, the chroma C ^* of the resin film A and / or the resin film B is 6 or more, and the chroma C _AB ^{* of the} resin sheet formed by laminating the resin film A and the resin film B is 5 or less. It is preferable that When the chroma C _AB ^* of the resin sheet is greater than 5, it can be easily confirmed visually that it is not an achromatic color, so it is not suitable as a design resin sheet for metal replacement. In addition, it is possible to bring the saturation C _AB ^* closer to an achromatic color by laminating them via an adhesive layer. The saturation C _AB ^* is preferably 3 or less. In this case, since it looks an achromatic color visually, it is very preferable as a design property.

  The resin film A and the resin film B of the present invention are preferably subjected to corona treatment. By performing the corona treatment, the affinity between the resin film, the adhesive layer and the adhesive and the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer is improved, and higher adhesive strength can be obtained.

  As a technique for improving the affinity between the adhesive, the pressure-sensitive adhesive, and the resin film, surface treatment such as plasma treatment, flame treatment, electron beam irradiation treatment, roughening treatment, ozone treatment may be performed.

In the resin sheet of the present invention, the difference in thermal shrinkage between the film longitudinal direction and the width direction in a 150 ° C. atmosphere is preferably 3% or less. More preferably, it is 1.5% or less. When the difference in thermal shrinkage rate is larger than 3%, the difference in the thermal shrinkage rate between the longitudinal direction and the width direction during molding is large, which is not preferable because it is difficult to use in a design application in which positional accuracy is required. If it is 1.5% or less, the heat shrinkage rate is almost the same, so that the positional accuracy is maintained, and when performing three-dimensional molding, it is stretched with good balance regardless of the longitudinal direction and the width direction, which is preferable. It is.
The resin sheet of the present invention preferably has a tear strength of 5 N / mm or more. More preferably, it is 10 N / mm or more. If it is less than 5 N / mm, the resin sheet may be torn in the trimming step after molding, which is not preferable.

The resin film of the present invention has an easy-adhesion layer, an easy-slip layer, a hard coat layer, an antistatic layer, an abrasion-resistant layer, an antireflection layer, a color correction layer, an electromagnetic wave shielding layer, an ultraviolet absorption layer, a printing layer, Functional layers such as a transparent conductive layer, a gas barrier layer, a hologram layer, a release layer, an adhesive layer, and an adhesive layer may be formed.
As the molded product of the present invention, in addition to the resin film of the present invention, a color absorbing layer that absorbs black or a color complementary to the reflection peak, a hard coat layer, a weather resistant layer (UV cut layer), a colored layer, an adhesive layer It is also preferable that any one of the base resin layers is included. Such a molded body can be composed of an all polymer and does not contain metal or heavy metal. Therefore, it has a small environmental load, is excellent in recyclability, and does not cause electromagnetic interference.
Next, the preferable manufacturing method of the resin sheet of this invention is demonstrated below.
When the resin film is a laminated polyester film, two types of resins X and Y are prepared in the form of pellets or the like. The pellets are pre-dried in hot air or under vacuum as necessary and supplied to the extruder. In the extruder, the resin melted by heating to a temperature equal to or higher than the melting point is made uniform by a gear pump or the like, and the foreign matter or modified resin is removed through a filter or the like. Further, the resin is formed into a desired shape with a die and then discharged.

  As a method for obtaining the resin film of the present invention, the resins sent out from different flow paths using two or more extruders are then fed into the laminating apparatus. As a laminating apparatus, a method of laminating in multiple layers using a multi-manifold die, a feed block, a static mixer, or the like can be used. Moreover, you may combine these arbitrarily. Here, in order to efficiently obtain the effects of the present invention, a multi-manifold die or a feed block capable of individually controlling the layer thickness for each layer is preferable. The structure of the feed block has at least one member on a comb-shaped slit plate having a large number of fine slits, and resin X and resin Y extruded from two extruders are slit through each manifold. Introduced into the board. Here, since the resin X and the resin Y selectively flow alternately into the slit through the introduction plate, finally, a multilayer film such as X / Y / X / Y / X... Can be formed. . Further, the number of layers can be increased by further overlapping the slit plates, and the thickness of each layer can be controlled by adjusting the gap between the slit plates.

In order to reduce the amount of foreign matter deposited after heat treatment in an atmosphere of 230 ° C. for 60 seconds and then heat treatment in an atmosphere of 90 ° C. for 240 hours to 50 pieces / mm ² or less, which is a feature of the present invention, It is preferable that the thickness of the thermoplastic resin layer which is in close contact is 200 nm or less. More preferably, it is 150 nm or less. By reducing the thickness of the surface layer, it is possible to suppress the oligomer surface precipitation, which is one of the causes of foreign matters. Further, as a second method, it is also preferable that the surface layer on the bonding surface side is formed of an amorphous resin or a resin having ΔHm of 200 ° C. or less. It is also preferable to provide an easy-adhesion layer having an oligomer precipitation inhibiting effect.

Further, by laminating two kinds of resins having different refractive indexes, the reflectance can be obtained at an arbitrary wavelength using the following formula 1. Further, the reflection wavelength order can be arbitrarily adjusted by the thickness of each layer. The reflectance is controlled by the refractive index difference between the A layer and the B layer and the number of layers of the A layer and the B layer.
2 × (na · da + nb · db) = λ Equation 1
na: In-plane average refractive index of the A layer nb: In-plane average refractive index of the B layer da: Layer thickness (nm) of the A layer
db: Layer thickness of layer B (nm)
λ: main reflection wavelength (primary reflection wavelength)
Furthermore, it is preferable to include a layer structure in which the layer thickness gradually increases from one surface to the opposite surface. In this case, since the reflectance can be obtained in a wide band, the resin film is excellent in design.

  The molten laminate formed in the desired layer configuration in this way is then formed into a desired shape by a die and then discharged. And the sheet | seat laminated | stacked in the multilayer discharged | emitted from die | dye is extruded on cooling bodies, such as a casting drum, and is cooled and solidified, and a casting film is obtained. At this time, using a wire-like, tape-like, needle-like or knife-like electrode, it is brought into close contact with a cooling body such as a casting drum by electrostatic force and rapidly cooled and solidified, or from a slit-like, spot-like, or planar device. A method in which air is blown out and brought into close contact with a cooling body such as a casting drum and rapidly cooled and solidified, and a method in which the nip roll is brought into close contact with the cooling body and rapidly solidified is preferable.

  The casting film thus obtained is preferably biaxially stretched as necessary. Biaxial stretching refers to stretching in the longitudinal direction and the width direction. Stretching may be performed sequentially biaxially or simultaneously in two directions. Further, the film may be redrawn in the longitudinal and / or width direction. In particular, in the present invention, it is preferable to use simultaneous biaxial stretching from the viewpoint of suppressing in-plane orientation difference and suppressing surface scratches.

  First, the case of sequential biaxial stretching will be described. Here, stretching in the longitudinal direction refers to stretching for imparting molecular orientation in the longitudinal direction to the film, and is usually performed by a difference in peripheral speed of the roll, and this stretching may be performed in one step. Alternatively, a plurality of roll pairs may be used in multiple stages. Although it changes with kinds of resin as a magnification of extending | stretching, 2 to 15 times is preferable normally, and when polyethylene terephthalate is used for either of the resin which comprises a laminated | multilayer film, 2 to 7 times are used especially preferably. Moreover, as extending | stretching temperature, the glass transition temperature-glass transition temperature +100 degreeC of resin which comprises a laminated | multilayer film are preferable.

  The uniaxially stretched film thus obtained is subjected to surface treatment such as corona treatment, flame treatment and plasma treatment as necessary, and then functions such as slipperiness, easy adhesion and antistatic properties are provided. It may be applied by in-line coating.

The stretching in the width direction refers to stretching for giving the film an orientation in the width direction. Usually, the tenter is used to convey the film while holding both ends of the film with clips, and the film is stretched in the width direction. Although it changes with kinds of resin as a magnification of extending | stretching, 2 to 15 times is preferable normally, and when polyethylene terephthalate is used for either of the resin which comprises a laminated | multilayer film, 2 to 7 times are used especially preferably. Moreover, as extending | stretching temperature, the glass transition temperature-glass transition temperature +120 degreeC of resin which comprises a laminated | multilayer film are preferable. The biaxially stretched film is preferably subjected to a heat treatment at a temperature not lower than the stretching temperature and not higher than the melting point in the tenter in order to impart flatness and dimensional stability.
Next, the case of simultaneous biaxial stretching will be described. In the case of simultaneous biaxial stretching, a difference in reflectance between reflection peaks in the width direction can be easily adjusted to ± 10% or less, which is preferable. In the case of simultaneous biaxial stretching, the resulting cast film is subjected to surface treatment such as corona treatment, flame treatment, and plasma treatment as necessary, and then, such as slipperiness, easy adhesion, antistatic properties, etc. The function may be imparted by in-line coating.

  Next, the cast film is guided to a simultaneous biaxial tenter, and conveyed while holding both ends of the film with clips, and stretched in the longitudinal direction and the width direction simultaneously and / or stepwise. As simultaneous biaxial stretching machines, there are pantograph method, screw method, drive motor method, linear motor method, but it is possible to change the stretching ratio arbitrarily and drive motor method that can perform relaxation treatment at any place or A linear motor system is preferred. Although the stretching magnification varies depending on the type of resin, it is usually preferably 6 to 50 times as the area magnification. When polyethylene terephthalate is used as one of the resins constituting the laminated film, the area magnification is 8 to 30 times. Is particularly preferably used. In particular, in the case of simultaneous biaxial stretching, it is preferable to make the stretching ratios in the longitudinal direction and the width direction the same and to make the stretching speeds substantially equal in order to suppress the in-plane orientation difference. Moreover, as extending | stretching temperature, the glass transition temperature-glass transition temperature +120 degreeC of resin which comprises a laminated | multilayer film are preferable.

  The biaxially stretched film is then subjected to a heat treatment in the tenter between the stretching temperature and the melting point in order to make the difference in heat shrinkage in the longitudinal and width directions 3% or less, which is a feature of the resin film of the present invention. Is preferred. In order to suppress the distribution of the main orientation axis in the width direction during this heat treatment, relaxation treatment may be performed instantaneously in the longitudinal direction and / or the width direction immediately before and / or immediately after entering the heat treatment zone.

  The resin sheet of the present invention is characterized in that the resin film A and the resin film B are laminated via an adhesive layer or an adhesive layer. As an adhesion method using the adhesive layer and the pressure-sensitive adhesive layer, lamination can be performed by a dry lamination method, a wet lamination method, a hot melt lamination method, or the like using a conventional solvent-type adhesive.

  The adhesive coating method is gravure coater, gravure reverse coater, lip coater, flexo coater, blanket coater, roll coater, knife coater, air knife coater, kiss touch coater, kiss touch reverse coater, comma coater, comma reverse coater, micro A coating method such as a reverse coater can be used. The application amount of the adhesive or the pressure-sensitive adhesive is preferably in the range of 0.1 to 30 g / m2, more preferably 2 to 15 g / m2. If it is less than 2 g / m 2, the adhesive strength is weak and it is easy to peel off, which is not preferable. When it is more than 15 g / m 2, the drying property is lowered and the appearance is liable to be poor. Moreover, it is not preferable because the imprint of foreign matter is likely to remain, resulting in a decrease in design properties.

  The resin sheet of the present invention includes a hard coat layer, an antistatic layer, an abrasion resistant layer, an antireflection layer, a color correction layer, an ultraviolet absorption layer, a printing layer, a metal layer, a transparent conductive layer, a gas barrier layer, a hologram layer, and a release layer. A functional layer such as an adhesive layer, an embossed layer, an adhesive layer, or a release layer may be formed.

The property value evaluation method, adhesive, and pressure-sensitive adhesive used in the present invention will be described.

(Method for evaluating physical properties)
(1) Lamination thickness, adhesive and pressure-sensitive adhesive layer thickness, number of laminations,
The layer structure of the film was determined by observation with an electron microscope for a sample whose cross section was cut out using a microtome. That is, using a transmission electron microscope H-7100FA type (manufactured by Hitachi, Ltd.), the cross section of the film was magnified 40000 times at an acceleration voltage of 75 kV, a cross-sectional photograph was taken, the layer configuration, and the thickness of each layer were measured. . In some cases, a known dyeing technique using RuO4 or OsO4 may be used to obtain high contrast.

  A specific method for obtaining the laminated structure will be described. About 40,000 times as many TEM photographic images were captured with CanonScan D123U at an image size of 720 dpi. The image is saved in the JPEG format, and then image processing software Image-Pro Plus ver. 4 (sales company Planetron Co., Ltd.) was used to open this JPG file and perform image analysis. In the image analysis process, the relationship between the thickness in the thickness direction and the average brightness of the area sandwiched between the two lines in the width direction was read as numerical data in the vertical thick profile mode. Using the spreadsheet software (Excel2000), the position (nm) and brightness data were subjected to numerical processing of sampling step 6 (decimation 6) and 3-point moving average. Furthermore, the data obtained by periodically changing the brightness is differentiated, and the maximum value and the minimum value of the differential curve are read by the VBA program. Calculated. This operation was performed for each photograph, and the layer thicknesses of all layers were calculated.

(2) Intrinsic viscosity Calculated from the solution viscosity measured at 25 ° C in orthochlorophenol. The solution viscosity was measured using an Ostwald viscometer. The unit is [dl / g]. The n number was 3, and the average value was adopted.

(3) Relative Reflectance A 60 mm integrating sphere (inner surface coated BaSO ₄ ) and a 10 ° inclined spacer were attached to a spectrophotometer U4100 manufactured by Hitachi High-Technologies Corporation to measure the reflectance. In order to standardize the reflectance, an Al ₂ O ₃ plate was used as a standard reflector. The measurement was performed under the following conditions.
Detection speed: 600 nm / min for wavelengths of 240 to 850 nm
Wavelength 850-1750nm is 750nm / min
Sampling interval: 1.00 nm
Slit: Wavelength 240-850nm is 2.00nm
Wavelength 850-1750nm is automatically controlled PbS sensitivity: 2
(4) A single film was formed under the same film forming conditions as the laminated film, using the thermoplastic resin constituting the in-plane refractive index difference laminated film between different thermoplastic resins alone. In this case, the unstretched film was formed by the same method up to casting. Next, a sample was cut out from the unstretched film to a size of 10 cm × 10 cm, stretched at the same magnification as the laminated film using a Brookner film stretcher KARO-IV, and the obtained stretched film was further subjected to a 20 cm × 20 cm metal frame Then, using a tunnel oven (manufactured by Taishin Manufacturing Co., Ltd.), heat treatment was performed at the same temperature as the laminated film to obtain a single film. In addition, when the heat treatment temperature at the time of film formation was a temperature at which the thermoplastic resin was melted, it was sandwiched by a support such as a polyimide film and subjected to heat treatment in a tunnel oven. A sample was cut out from the center of the obtained single film in the width direction of the film in a dimension of 4 × length 3.5 cm, and the refractive index of MD and TD was measured using an Abbe refractometer 4T (manufactured by Atago Co., Ltd.). Asked. As a light source, a sodium D line wavelength of 589 nm was used. The average refractive index of MD and TD was determined as the in-plane refractive index, and the difference in in-plane refractive index between different thermoplastic resins was determined as the in-plane refractive index difference (absolute value) (| surface of thermoplastic resin A Internal refractive index—In-plane refractive index of thermoplastic resin B |). As the immersion liquid, methylene iodide and a test piece having a refractive index of 1.74 were used.

(5) High elongation In accordance with the method defined in JIS-K7127 (1999), it was measured using an Instron type tensile tester. The elongation is set to a high value in either the film longitudinal direction or the width direction. The measurement was performed under the following conditions.
Measuring device: “Tensilon AMF / RTA-100” automatic tensile strength measuring device manufactured by Orientec Co., Ltd.
Sample size: width 10mm x test length 50mm
Pulling speed: 300mm / min
Measurement environment: Temperature 100 ° C
(6) A 90 ° peel strength resin sheet (a laminate film and a different material or the same kind of laminate film) is cut into a size of 25 cm in length and 1.5 cm in width and attached to a plastic substrate. At this time, the thicker film is defined as the plastic substrate side. Thereafter, about 10 to 15 cm of one side of the resin sheet is peeled off with the adhesive layer as a boundary. If peeling is difficult, the solvent is removed and the adhesive is removed. The peeled film was measured for strength at the time of peeling using a 90 degree peel tester manufactured by Imada Co., Ltd. The measurement was performed under the following conditions.
Measuring device: 90 degree peel tester manufactured by Imada Co., Ltd.
Force gauge: ZP
Test stand: MX-500N-E-L550
Attachment: P90-200N
Software: ZP-Recorder
Sample size: width 15mm x test length 50mm
Tensile speed: 200 mm / min
Measurement environment: temperature 23 ° C., humidity 65% RH.
The average peel strength for a peel distance of 50 mm was used.

(7) Resin film chroma C * and resin sheet chroma C _AB *
Cut out the sample at 5 cm x 5 cm, then paint one side of the sample black with Magic Ink (registered trademark), and set the side opposite to the blacked side to the light source side, CM-3600d manufactured by Konica Minolta Co., Ltd. Measurement was performed using In addition, the measurement average value of 3 times was used. The measurement was performed under the following conditions.
Measuring device: Konica Minolta Sensing Co., Ltd.
White calibration plate: CM-A103
Zero calibration box: CM-A104
Measurement mode: reflection SCI method (including regular reflection light and diffuse reflection light)
Measurement diameter: φ8mm target mask (CM-A106)
Viewing angle: 10 ° Viewing light source: D65
(8) Color difference (ΔEab)
A sample was cut out at 10 cm × 10 cm, and after measuring a _s * value and b _s * value, the sample was placed in a hot air oven maintained at 90 ° C. and left unloaded for 30 minutes, and then taken out to room temperature. . The a _e * value and the b _e * value were measured while making the measurement positions the same for this sample, and the color difference (ΔEab) before and after the heat treatment was determined by the following formula 1.
Note that the measurement conditions are the same as the saturation C *. However, the black coating of the sample is not performed.

ΔEab = ((a _e ^* −a _s ^* ) ² + (b _e ^* −b _s ^* ) ² ) ^1/2 Formula 1
(9) Haze value The resin sheet whose haze value was measured was placed in a hot air oven maintained in an atmosphere of 150 °, left unloaded for 30 minutes, and then taken out to room temperature. About this sample, the haze was measured while making the measurement position the same, and the difference (ΔHaze) between the haze values before and after the heat treatment was obtained.
In addition, the measurement used direct reading type haze meter HGM-2DP (made by Suga Test Instruments Seisakusho). The haze (%) was calculated by dividing the diffuse transmittance by the total light transmittance and multiplying by 100.

(10) The heat shrinkage rate film was sampled to a width of 10 mm and a length of 150 mm, and marked lines with an interval of about 100 mm were marked on the sample, and then the distance between the marked lines was accurately measured using a universal projector. Next, the film sample was suspended in the length direction, a load of 3 g was applied in the length direction, and the film sample was heated in a hot air oven maintained at 150 ° C. for 30 minutes. The distance between the marked lines after heating was measured, and the amount of shrinkage of the film was expressed as a percentage with respect to the original dimension. The difference between the film longitudinal direction and the width direction was calculated.

(11) Tear strength The tear strength (gf) was measured based on JIS K 7128-2 (Elemendorf tear method) using a light load tear tester (manufactured by Toyo Seiki). The measured value was multiplied by 9.8 and divided by the measured film thickness to obtain the tear strength mN / μm. The tear strength was obtained by averaging the test results of 5 samples each in the longitudinal direction and the transverse direction.

(12) Foreign matter precipitation amount The resin sheet is cut out in a size of 10 cm × 10 cm, and arbitrary five places are surface-observed at a total magnification of 200 times with a differential interference microscope (Leica DMLM) manufactured by Leica Microsystems Co., Ltd., and the number of foreign matters is counted. To do. The foreign substance here is defined as a substance having a maximum diameter of 1 μm or more. Thereafter, this resin sheet is fixed to a 10 cm × 10 cm metal frame so that thermal contraction does not occur, and overheated for 60 seconds in a tunnel oven (manufactured by Taishin Seisakusho) heated to 230 ° C., and then kept in an atmosphere at 90 ° C. It put in the hot air oven which drew, and heat-processed for 240 hours in the unweighted state. The surface of this sample was observed at a total magnification of 200 times of a differential interference microscope while keeping the measurement position the same, and the number of foreign matters was counted. A value obtained by subtracting the number of foreign matters before heat treatment from the number of foreign matters after heat treatment at each measurement location was calculated, and the average value of the five points was defined as the amount of foreign matter deposited (pieces / mm ² ).

(13) Molding test and punching process The resin sheet was molded with a vacuum / pressure forming machine TYPE: FKS-0631-20 owned by Asano Laboratories, and then punched. After molding, when peeling was observed with a resin sheet visually after punching, it was rated as x, and when peeling did not occur, it was marked as ◯. The molding conditions are shown below.
Molding method: Vacuum pressure molding Pressure: 0.6 MPa
Mold: concave cylindrical shape, depth 5mm, radius 20mm
Further, the obtained molded body was subjected to a heat cycle test, and then an adhesion test by a cross-cut method was performed. The method conforms to JIS K5600-5-6 (1999). In the case where peeling occurred visually, the mark was x. The heat cycle test was carried out under the condition that a total of 18 cycles was carried out under the condition that “the sample was left in a −40 ° C. atmosphere for 2 hours and then left in a + 85 ° C. atmosphere for 2 hours in a weighted state”.

(Adhesives and adhesives)
<Adhesive A>
5 parts by weight of LX660 manufactured by Dainippon Ink & Chemicals, Inc. and 1 part by weight of KW75 manufactured by Dainippon Ink & Chemicals, Inc. were dissolved in 2 parts by weight of ethyl acetate.

<Adhesive B>
5 parts by weight of urethane prepolymer solution “Takenate A-975” manufactured by Mitsui Chemicals Polyurethanes Co., Ltd. and 0.5 part by weight of urethane prepolymer solution “Takelac A-12” manufactured by Mitsui Chemicals Polyurethanes Co., Ltd. are dissolved in 5 parts by weight of ethyl acetate. Made.

<Adhesive C>
It was prepared by dissolving 1 part by weight of SK Dyne 1502C manufactured by Soken Chemical Co., Ltd., 7 parts by weight of the crosslinking agent E-5XM, 3 parts by weight of L-45, and 1 part by weight of toluene.

<Adhesive D>
Acrylic resin adhesive SK Dyne 2094 and crosslinkers E-5XM, L-45 manufactured by Soken Chemical Co., Ltd. are used as diluent / toluene / methyl ethyl ketone / cyclohexane = 27 g / 27 g / 4 g, and adhesive / E-5XM / L-45 / dilution It produced so that it might become a ratio of solvent = 200g / 0.5g / 0.7g / 60g.

Example 1
For both the resin films A and B, polyethylene terephthalate (PET) [Toray F20S] having an intrinsic viscosity of 0.65 was used as the thermoplastic resin X. The thermoplastic resin X is a crystalline resin. Further, as the thermoplastic resin Y, a copolymer of polyethylene terephthalate having an intrinsic viscosity of 0.55 (polyethylene terephthalate copolymerized with 20 mol% of cyclohexanedicarboxylic acid component and 15 mol% of spiroglycol component (CHDC 20 mol% / SPG 15 mol% copolymerized PET)) was used. These thermoplastic resins X and Y were dried and then fed in separate extruders.

  Thermoplastic resins X and Y are each melted at 270 ° C. with an extruder, passed through 5 sheets of FSS type leaf disk filters, and then discharged at a gear pump with a thermoplastic resin X composition / thermoplastic resin. While being measured so that Y composition = 1.07 / 1.0, a 801-layer feed block having a configuration using three slit plates with 267 slits was joined to form a laminate. The joined thermoplastic resins X and Y are changed so that the thickness of each layer gradually increases from the surface side to the opposite surface side in the feed block. The thermoplastic resin X is 401 layers and the thermoplastic resin Y is 400 layers. It was set as the structure laminated | stacked alternately in the thickness direction which consists of layers. In addition, the slit shape was designed so that the layer thicknesses of the adjacent A layer and B layer were substantially the same. The slit shape was designed so that the thickness of the thermoplastic resin layer closest to the adhesive layer was 50 nm. In this design, there is a reflection band from 350 nm to 1000 nm. The thus obtained laminate comprising a total of 801 layers was supplied to a multi-manifold die, formed into a sheet shape, and then rapidly cooled and solidified on a casting drum maintained at a surface temperature of 25 ° C. by electrostatic application. . The flow path shape and the total discharge amount were set so that the time from when the resin X and the resin Y merged to when rapidly solidified on the casting drum was about 8 minutes.

  The obtained cast film was heated with a roll group set at 75 ° C., and then stretched 3.0 times in the longitudinal direction while rapidly heating from both sides of the film with a radiation heater between 100 mm in the stretch section length. Cooled down. Next, the one side of the film was subjected to corona treatment, led to a tenter, preheated with hot air at 100 ° C., and stretched 3.3 times in the transverse direction at a temperature of 110 ° C. The stretched film was directly heat-treated in a tenter with hot air of 235 ° C., subsequently subjected to a relaxation treatment of 6% in the width direction at the same temperature, and then gradually cooled to room temperature and wound up. Resin film A was 91.4 μm. Further, a resin film B having a thickness of 64.4 μm was obtained by the same method.

  Adhesive A is applied 7 μm with a lip coater using a die-type dry laminator on the surface of the resin film B having a thin film thickness, which has been subjected to corona treatment, and the resin film A is laminated with the corona-treated surface. To obtain a resin sheet. In dry lamination, the solvent drying temperature of the adhesive was changed from 60 degrees to 80 degrees, the nip pressure during lamination was 4.0 kg / cm3, the nip temperature was 80 degrees, and aging was performed at 40 ° C. for 3 days.

The obtained resin sheet has a chroma _CAB ^* of 0.6, which is almost achromatic, has a high metallic luster tone with high reflectivity, and has almost no difference in haze value before and after heat treatment and foreign matter precipitation. It was excellent in design properties. Further, while maintaining the elongation at 180%, the peel strength was as high as 1.69, and thus the moldability was excellent. The obtained results are shown in Table 1.

(Example 2)
In Example 1, after supplying the laminated film to the multi-manifold die, the amount of the thermoplastic resin Y from another extruder is adjusted on the surface layer so that the thickness is 50% of the average layer thickness, and laminated to obtain 803 layers. The conditions were the same as in Example 1 except that the corona treatment on the adhesive interface was not performed.
The obtained resin sheet was excellent in design property although the adhesive strength was slightly low. The obtained results are shown in Table 1.

(Example 3)
In Example 1, the thermoplastic resin Y is a polyethylene terephthalate copolymerized with 30 mol% of cyclohexanedimethanol (CHDM copolymerized PET) [Eastman's PETG6763] and an intrinsic viscosity of 0.65 polyethylene terephthalate in a weight ratio of 85:15. The conditions were the same except that the resin was kneaded and alloyed with a twin-screw extruder and B was used as the adhesive used for lamination.
The obtained resin sheet had a low reflectance because the difference in refractive index between the laminated resins was low. Moreover, the peeling strength fall by the adhesive agent origin was seen. The obtained results are shown in Table 1.

Example 4
In Example 3, the same conditions were used except that the resin sheet was not subjected to corona treatment. The obtained resin sheet had a lower adhesive strength than that with corona treatment, and the haze value was increased by heat treatment by changing the resin of the sub-layer. The results are shown in Table 1.

(Example 5)
In Example 4, after the laminated film is supplied to the multi-manifold die, the thermoplastic resin X is further laminated on the surface layer from another extruder by adjusting the discharge amount so that the layer thickness is equal to the average layer thickness. It was. The adhesive layer was 3 μm. Other conditions were the same as in Example 4.
The resulting resin sheet has an increased amount of foreign matter deposited by increasing the thickness of the surface PET layer, an increased amount of haze value after heat treatment, and a decrease in peel strength by reducing the thickness of the adhesive layer. Was seen. The obtained results are shown in Table 1.

(Example 6)
In Example 1, the conditions were the same except that the adhesive was C. The obtained results are shown in Table 1.

(Example 7)
In Example 1, after the laminated film is supplied to the multi-manifold die, the thermoplastic resin X is further laminated on the surface layer from another extruder by adjusting the discharge amount so that the layer thickness is equal to the average layer thickness. The conditions were the same except that.
The obtained resin sheet had a slightly increased foreign matter precipitation amount and a slightly reduced quality as a design property due to the thickening of the PET layer on the surface layer. The obtained results are shown in Table 1.

(Example 8)
In Example 7, polyethylene terephthalate copolymerized with 30 mol% of cyclohexanedimethanol (CHDM copolymerized PET) [PETG6763 manufactured by Eastman] and polyethylene terephthalate with an intrinsic viscosity of 0.65 in a weight ratio of 85:15 were used for thermoplastic resin Y. The conditions were the same except that the resin was kneaded and alloyed with a twin-screw extruder.
The obtained resin sheet resulted in an increase in the amount of foreign matter deposited due to the change of the sub-layer and the thickening of the PET layer. The obtained results are shown in Table 2.

Example 9
In Example 1, the resin film A was formed in a 51-layer feed block, the slit was adjusted so that the thickness of the thermoplastic resin layer closest to the adhesive layer in the feed block was 10 nm, The thickness of each layer was made constant from the surface side to the opposite surface side. The resin film B was an acrylic film (Technoloy S001) manufactured by Sumitomo Chemical Co., Ltd. Other conditions were the same as in Example 1.
The obtained resin sheet had weather resistance, reflected only light of a specific wavelength, and was excellent in design with depth. The obtained results are shown in Table 2.

(Example 10)
The same conditions were used except that the feed block was 201 layers in Example 1.
The obtained resin sheet had a low reflectance due to the small number of layers. The obtained results are shown in Table 2.

(Example 11)
In Example 1, the same conditions were used except that the resin film B was an acrylic film (Technoloy S001) manufactured by Sumitomo Chemical Co., Ltd.
The obtained resin sheet had weather resistance and was excellent in design that allows the depth to be felt. The obtained results are shown in Table 2.

(Comparative Example 1)
In Example 1, the conditions were the same except that the adhesive coating thickness was 1 μm.
The obtained resin sheet had low adhesive strength and peeled off during stretching. The obtained results are shown in Table 3.
(Comparative Example 2)
In Example 1, the conditions were the same except that the adhesive was D and the thickness of the adhesive layer was 3 μm. The obtained resin sheet had low adhesive strength, and peeling occurred during stretching and stamping after molding. The obtained results are shown in Table 3.

(Comparative Example 3)
In Example 1, the thermoplastic resin Y is a polyethylene terephthalate copolymerized with 30 mol% of cyclohexanedimethanol (CHDM copolymerized PET) [PETG6763 manufactured by Eastman] and polyethylene terephthalate having an intrinsic viscosity of 0.65 in a weight ratio of 50:50. The conditions were the same except that the resin was kneaded and alloyed with a twin-screw extruder and the adhesive coating thickness was 1 μm.
The obtained resin sheet had a haze value increased by heating and a large color change. The obtained results are shown in Table 3.

  The present invention relates to a resin sheet in which at least two types of resin films are laminated via an adhesive layer or an adhesive layer. More specifically, the present invention relates to a decorative material having high design properties such as glossiness and depth, such as a decorative member, for example, a decorative material for automobiles and mobile phones.

Claims (9)

Resin film A and resin film B are resin sheets laminated via an adhesive layer or a pressure-sensitive adhesive layer, 90 ° peel strength at the adhesive part is 0.3 kg / cm or more, and haze before heat treatment The difference in haze value after heat treatment for 30 minutes in an atmosphere at 150 ° C. is 3% or less, and the elongation in the longitudinal direction and / or the width direction at 100 ° C. is 100% or more. Resin sheet. Each of the resin film A and / or the resin film B has 50 layers or more alternately of layers (X layer) mainly composed of the thermoplastic resin X and layers (Y layer) mainly composed of the thermoplastic resin Y. 2. The resin sheet according to claim 1, which is a laminated resin film, and has a color difference (ΔEab) of 10 or less before heat treatment and after heating for 30 minutes in a 90 ° C. atmosphere. The resin sheet is heat-treated in an atmosphere of 230 ° C. for 60 seconds, and then subjected to a heat treatment in an atmosphere of 90 ° C. for 240 hours, and the amount of deposited foreign matter having a size of 1 μm or more is 30 / mm ² or less. The resin sheet of description. The chroma C ^{* of the} resin film A and / or the resin film B is 6 or more, and the chroma C _AB ^{* of a} resin sheet formed by laminating the resin film A and the resin film B is 5 or less. The resin sheet in any one of. The resin sheet according to any one of claims 1 to 4, wherein the adhesive layer and / or the pressure-sensitive adhesive layer is any one of a polyester urethane resin, a urethane resin, and an acrylic resin. The resin sheet according to claim 1, wherein the resin film A and the resin film B are subjected to corona treatment. The resin sheet according to any one of claims 1 to 6, wherein a difference in heat shrinkage between the film longitudinal direction and the width direction in a 150 ° C atmosphere is 3% or less. The resin sheet according to any one of claims 1 to 7, wherein the tear strength of the resin sheet is 5 N / mm or more. The molded object using the resin sheet in any one of Claim 1 to 8.