JP2006289818A - Decorative laminated sheet and manufacturing method of covered molding - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a decorative laminated sheet, which is a decorative molding sheet having a surface layer in whcih a curing reaction is prevented from excessively advancing by high temperature heating just before molding and which has high elongation at molding (having an extension ratio of at least 300%) and can obtain a covered molding with an excellent exterior appearance and surface gloss. <P>SOLUTION: This decorative laminated sheet is formed by laminating the surface layer (A), a transparent or translucent thermoplastic resin layer (B), an ink layer (C) and a supporting base material layer (D) in the order named. The surface layer (A) includes a thermoplastic resin, which includes a second-grade hydroxyl group, has an acid value of not more than 1.0 (KOH mg/g) and a glass transition temperature, and a polyisocyanate compound, which is a half-cured layer in its 20-80% reactive isocyanate. The manufacturing method of the covered molding comprises the step of bringing the decorative laminated sheet into contact with the surface of a mold when the temperature of the sheet is kept at 100°C or higher. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a laminated sheet for decoration particularly useful for decoration of automobile interior / exterior parts, parts for home appliances, parts for building materials, and the like.

  Conventionally, automotive interior / exterior parts, home appliance parts, building material parts, etc. for decorative purposes have been subjected to injection molding, vacuum molding, in-mold molding, etc., and then the surface of the molded product is applied by spray painting or the like. , Dried and heat-cured to impart design properties such as surface protection, coloring and decoration of the molded product. However, such a coating has a problem of low productivity because it requires a work environment for discharging the volatile organic solvent and a work process and production equipment such as coating, drying and heat curing for each molded product.

  On the other hand, in recent years, a decorative laminated sheet made of a soft thermoplastic resin having design properties at the time of molding processing has been provided, and the decorative laminated sheet is bonded to the surface of the molded product to provide a coated molded product having design properties. Many methods have been proposed. The decorative sheet is made of a thermoplastic resin that can follow the three-dimensional deformation during thermoforming, so there are no problems such as cracking, tearing or peeling of the coating film during molding, and there is no painting process. Excellent work environment and productivity. However, the surface hardness is limited, and there are problems such as poor scratch resistance and solvent resistance.

In order to solve this problem, a method has been developed in which a decorative laminated sheet having a curable resin layer as a surface layer is used and cured after molding to obtain a coated molded product. In this method, the curable resin layer, which is a surface layer, is uncured at the stage of molding processing, so that the stretchability is high, and the curable resin layer is cured after the molded product is coated. Has high hardness and excellent scratch resistance.
However, the uncured curable resin easily adheres to the mold surface due to heat during molding, and as a result, the appearance of the molded product integrated with the decorative laminated sheet may be impaired. In addition, there is a problem in that the deposits must be removed from the mold and productivity is poor.

  A decorative laminated sheet has been developed in which a curable resin layer, which is a surface layer, is partially cross-linked before molding and is cured again after molding. (For example, see Patent Documents 1 and 2) This uses a mixture of a UV resin and a thermosetting resin, crosslinks the thermosetting resin component before molding (semi-cured state), and UV irradiation after molding. Thus, the UV curable resin component is crosslinked. Thereby, the problem that a deposit adheres to the mold can be solved. However, since it is necessary to perform UV irradiation after molding, it is complicated, the problem that the UV curable resin and the thermosetting resin are not compatible with each other, or the UV curable resin component generally has a low elongation rate. There was a problem that cracks and the like occurred during molding.

For example, Patent Document 3 is known as a decorative laminated sheet having a surface layer that uses only a thermal curing method without using a UV curing method. This is a sheet having a surface layer of a thermosetting resin mainly composed of a reactive acrylic resin having a hydroxyl group, an amino group or a carboxyl group and a blocked isocyanate, and is partially crosslinked by heat before molding. And thermosetting after molding. However, the curing reaction proceeds too much due to high-temperature heating immediately before vacuum molding or in-mold molding, and the laminated sheet cannot be extended during molding, especially the problem that the clear layer is likely to crack or peel, There was a problem that masking agents such as phenols and organic carboxylic acids were detached from the blocked isocyanate group and adhered to the mold or the surface of the molded product, leading to poor appearance of the molded product and a reduction in surface gloss.
JP 2000-117925 A JP 2004-1350 A Japanese Patent Laid-Open No. 03-157414

  The problem to be solved by the present invention is a decorative molded sheet having a surface layer that uses only a thermosetting method, the curing reaction does not proceed too much due to high-temperature heating immediately before molding, and the elongation at the time of molding It is to provide a decorative laminated sheet which is high (has a development ratio of 300% or more by a vacuum forming method) and is excellent in the appearance and surface gloss of the resulting coated molded product.

The inventors of the present invention have high reactivity between a reactive acrylic resin having a hydroxyl group, an amino group or a carboxyl group and a blocked isocyanate at the time of high-temperature heating immediately before vacuum molding or in-mold molding, and a curing reaction can be achieved even in a short heating time. Too much progress is considered to be the cause of low elongation at the time of molding,
Combining a thermoplastic resin with a slow reactive secondary hydroxyl group and with an acid value kept as low as possible and a polyisocyanate that is not blocked with a masking agent, the curing reaction proceeds by high-temperature heating immediately before molding. However, it was found that when the mold was molded, curing was achieved only by heat during molding, and the appearance and surface gloss of the resulting coated molded product were excellent.

  That is, in the present invention, a surface layer (A), a transparent or translucent thermoplastic resin layer (B), an ink layer (C), and a supporting base layer (D) are laminated in this order. A decorative laminated sheet, wherein the surface layer (A) contains a secondary hydroxyl group, an acid value of 1.0 (KOHmg / g) or less, and a glass transition temperature of 30 to 100 ° C, a thermoplastic resin; Provided is a decorative laminated sheet which is a layer containing a polyisocyanate compound and semi-cured in an isocyanate reaction rate of 20 to 80%.

  In addition, the present invention is a method for manufacturing a coated molded product by supplying a molding resin to a mold after the decorative laminated sheet according to claim 1 is brought into close contact with the mold surface. Provided is a method for producing a coated molded product having a sheet temperature of 100 ° C. or higher when the decorative laminated sheet is brought into close contact with the surface.

  According to the present invention, the curing reaction does not proceed excessively by heating at a high temperature immediately before molding, the elongation at the time of molding is high (having a development ratio of 300% or more by the vacuum molding method), and the appearance and surface of the resulting coated molded product A decorative laminated sheet having excellent gloss can be obtained.

(Surface layer (A))
In this invention, a surface layer is a layer used as the outermost surface of a three-dimensional molded object after vacuum forming or in-mold shaping | molding.
The surface layer (A) used in the present invention comprises a thermoplastic resin having a secondary hydroxyl group, an acid value of 1.0 (KOHmg / g) or less and a glass transition temperature of 30 to 100 ° C., and a polyisocyanate compound. It is a layer that is contained and semi-cured in an isocyanate reaction rate of 20 to 80%.
In a thermoplastic resin containing a secondary hydroxyl group and having an acid value of 1.0 (KOHmg / g) or less and a glass transition temperature of 30 to 100 ° C., the thermoplastic resin is an acrylic polymer or a fluoroolefin polymer. And polymers such as vinyl polymers, polyesters, alkyd resins, and polyurethanes. Among these, vinyl polymers are particularly preferable in terms of a good balance between moldability and physical properties of the molded product. A thermoplastic resin containing a secondary hydroxyl group and having an acid value of 1.0 (KOH mg / g) or less and a glass transition temperature of 30 to 100 ° C. is abbreviated as thermoplastic resin A.

(Thermoplastic resin A)
The thermoplastic resin A is obtained by homopolymerization or copolymerization by a known method. For example, when the thermoplastic resin A is a vinyl polymer, it can be obtained by homopolymerizing or copolymerizing a vinyl monomer having a secondary hydroxyl group by a known method. The vinyl monomer having a secondary hydroxyl group may be a compound having an unsaturated double bond and a secondary hydroxyl group in the molecule. For example, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, acrylic Unsaturated carboxylic acid monoalkyl ester compounds such as 2-hydroxybutyl acid and 2-hydroxybutyl methacrylate, adducts of unsaturated carboxylic acids and monoepoxy compounds such as α-olefin epoxides, glycidyl acrylate or glycidyl methacrylate Of dialkyl secondary amines such as dioctylamine, glycidyl acrylate or glycidyl methacrylate and fatty acids such as acetic acid and propionic acid, glycidyl acrylate or glycidyl methacrylate and inorganic acids such as hydrochloric acid There is a possible thing.

  The vinyl polymer containing the secondary hydroxyl group may be copolymerized with other general-purpose vinyl monomers. For example, methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, acrylate (n-, iso- or tert-) butyl, hexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, Decyl acrylate, lauryl acrylate, stearyl acrylate, cyclohexyl acrylate, methyl methacrylate, ethyl methacrylate,

N-propyl methacrylate, isopropyl methacrylate, methacrylic acid (n-, iso- or tert-) butyl, hexyl methacrylate, 2-ethylhexyl methacrylate, octyl methacrylate, decyl methacrylate, lauryl methacrylate, stearyl methacrylate, C1-C22 alkyl ester or cycloalkyl ester of acrylic acid or methacrylic acid such as cyclohexyl methacrylate;

Acrylic acid such as methoxybutyl acrylate, methoxybutyl methacrylate, methoxyethyl acrylate, methoxyethyl methacrylate, ethoxybutyl acrylate, ethoxybutyl methacrylate, etc. ) Acrylic acid esters include N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, N-tert-butylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl ( Aminoalkyl acrylate monomers such as (meth) acrylate;

Acrylamide monomers such as acrylamide, methacrylamide, N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N-butyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, glycidyl acrylate, glycidyl Examples thereof include glycidyl group-containing monomers such as methacrylate, vinyl aromatic compounds such as styrene, α-methylstyrene, and vinyl toluene, acrylonitrile, vinyl acetate, and vinyl chloride.

  Further, it is preferable to copolymerize a vinyl monomer having a primary hydroxyl group because the curing rate and the hydroxyl value can be adjusted. Examples of the vinyl monomer having a primary hydroxyl group include 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 3-hydroxypropyl acrylate, 3-hydroxypropyl methacrylate, 4-hydroxybutyl acrylate, 4-hydroxybutyl methacrylate, and the like. And an adduct of the above-mentioned hydroxyl group-containing monomer and a lactone (eg, ε-caprolactone, γ-valerolactone, etc.). In particular, it is more preferable to use an adduct of the above-mentioned hydroxyl group-containing monomer and a lactone (for example, ε-caprolactone, γ-valerolactone, etc.) because the three-dimensional deep drawability at the time of molding is improved.

  In order to further improve the gloss of the obtained molded product, it is effective to copolymerize a diallyl compound. Examples of diallyl compounds include allyl acrylate, allyl methacrylate, diallyl acetic acid, diallyl carbinol, diallyl ether, diallyl chlorosilane, and the like. From the viewpoint of the stability of the copolymer and the availability of raw material compounds, acrylic Allyl acid and allyl methacrylate are preferred. The diallyl compound is preferably used in the range of 0.5 to 30% by weight based on the total monomer components. By setting the amount to 0.5% by weight or more, the gloss value at 20 ° becomes 85 or more, and the gloss value at 60 ° which is also an index of gloss feeling felt by human eyes becomes 90 or more. As a result, extremely excellent gloss can be obtained. If the amount of diallyl compound used exceeds 30% by weight, the reaction mixture may gel in the reactor during production.

  As the homopolymerization or copolymerization method, a known polymerization method such as a solution radical polymerization method, a non-aqueous dispersion polymerization method or a bulk polymerization method can be used. Among these, the solution radical polymerization method is simple and preferable. Examples of the solution radical polymerization method include, for example, aromatic hydrocarbons such as xylene and toluene, alcohols such as isobutanol and n-butanol, esters such as butyl acetate, ketones such as methyl amyl ketone, cellosolve, Radical polymerization initiators such as azo compounds such as N, N-azobisdiisobutyronitrile, organic peroxides such as benzoyl peroxide, n-dodecyl mercaptan, etc. The reaction is carried out at a reaction temperature of about 50 to 160 ° C. for about 1 to 30 hours.

  The ratio of the secondary hydroxyl group of the thermoplastic resin A is preferably a ratio that occupies 50 to 100 mol% of the total hydroxyl group content of the thermoplastic resin A in view of particularly good three-dimensional moldability. When the proportion of the secondary hydroxyl group is less than 50 mol%, the effect of retarding the reaction of the secondary hydroxyl group with the isocyanate group becomes insufficient, and the curing reaction of the clear cured layer proceeds too much due to high-temperature heating during vacuum molding. In some cases, the film may be easily cracked or peeled off.

When the hydroxyl value of the thermoplastic resin A is in the range of 30 to 120 (KOH mg / g), the crosslink density of the clear cured layer is 1.0 × 10 ^{−5 to} 3.0 × 10 ⁻⁵ [mol / cm ^3. ], It is sufficient in terms of balance between moldability and physical properties of the coating film. By setting the hydroxyl value to 30 (KOHmg / g) or more, the crosslinked density of the cured coating film tends to be sufficient, and the solvent resistance tends to be good, and the hydroxyl value is set to 120 (KOHmg / g) or less. By doing so, cracking and peeling of the coating film due to stretching during molding tend to be remarkably reduced, and three-dimensional moldability tends to be good. A particularly preferable range of the hydroxyl value is 40 to 100 (KOHmg / g).

  The number average molecular weight (value in terms of polystyrene) of the thermoplastic resin A is preferably in the range of 5,000 to 50,000. When the number average molecular weight is 5,000 or more, the solvent resistance of the cured coating film tends to be good, and when the number average molecular weight is 50,000 or less, the three-dimensional formability tends to be good. A more preferable range is 10,000 to 30,000.

  The glass transition temperature (hereinafter abbreviated as Tg) derived from the fox calculation formula of the thermoplastic resin A is 30 to 100 ° C. By setting it as this range, it is possible to balance the moldability of the surface layer (A) and the physical properties of the coating film. By setting Tg to 30 ° C. or higher, the cured coating film becomes hard, cracking or peeling of the coating film due to stretching during molding is remarkably reduced, and solvent resistance and the like are further improved. Moreover, by making Tg 100 degrees C or less, a cured coating film becomes moderately soft, the crack and peeling of the coating film by extending | stretching at the time of shaping | molding reduce remarkably, and three-dimensional moldability becomes favorable.

The acid value of the thermoplastic resin A is 1.0 (KOHmg / g) or less. By setting it as this range, three-dimensional moldability becomes favorable. When the acid value exceeds 1.0 (KOHmg / g), the effect of the curing catalyst of the acid component becomes remarkable, and the curing reaction of the clear cured layer proceeds too much due to high-temperature heating during vacuum molding, and stretching during molding There is a problem that the coating film is easily cracked or peeled off.
The method for reducing the acid value can be easily performed, for example, by reducing or not using the amount of the compound that becomes the acid value component from the component constituting the surface layer (A). Although it does not specifically limit as an acid value component, (1) Acid value components, such as a carboxylic acid functional group, an acid anhydride functional group, a phenolic hydroxyl group, are mentioned as a polymerizable vinyl monomer used for a secondary hydroxyl group containing thermoplastic resin. (2) As a polymerization catalyst used for the synthesis of a secondary hydroxyl group-containing thermoplastic resin, a polymerization catalyst containing a carboxylic acid functional group in the thermal decomposition product, (3) inorganic acid, organic acid There are reaction solvents containing phenols, diluents, etc., and the amount of the acid value component used can be reduced so that the acid value of the thermoplastic resin A is 1.0 or less.

In the present invention, the amount of secondary hydroxyl group is 50% to 100% by mole of the total hydroxyl group, and the acid value is 1.0 (KOHmg / g) or less, so that a synergistic effect can be obtained. The moldability is particularly good.

(Polyisocyanate compound)
The polyisocyanate compound used in the present invention is a compound having an average of two or more isocyanate groups in one molecule. The number average molecular weight (value in terms of polystyrene) is preferably 10,000 or less, more preferably 5,000 or less, and particularly preferably 2,000 or less. Among these, it is preferable to use a so-called trivalent or higher isocyanate compound containing three or more isocyanate groups in one molecule.

  Specific examples of the trivalent or higher isocyanate compound include 2-isocyanatoethyl-2,6-diisocyanatocaproate, 1,3,5-triisocyanatocyclohexane, 2,4,6-triisocyanate. Aliphatic triisocyanates such as cycloheptane, 1,2,5-triisocyanatocyclooctane, aromatic triisocyanates such as 1,3,5-triisocyanatobenzene, 2,4,6-triisocyanatonaphthalene, diisocyanates And polyisocyanates having a so-called isocyanurate ring structure obtained by cyclization and trimerization.

  As the polyisocyanate compound, it is preferable to use divalent isocyanate compounds, that is, diisocyanates in combination with these trivalent or higher organic polyisocyanate compounds. Diisocyanates include aliphatic diisocyanates such as hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, dimer acid diisocyanate, lysine diisocyanate, hydrogenated xylylene diisocyanate, cyclohexylene diisocyanate, 1,3-bisisocyanate methylcyclohexane, 2-methyl. Cyclic aliphatic diisocyanates such as -1,3-diisocyanatocyclohexane, 2-methyl-1,5-diisocyanate cyclohexane, methylenebis (cyclohexyl isocyanate), isophorone diisocyanate,

  Tolylene diisocyanate, phenylene diisocyanate, diphenylmethane diisocyanate, m-xylylene diisocyanate, 4,4'-diphenylmethane diisocyanate xylylene diisocyanate, α, α, α ', α'-tetramethyl-m-xylylene diisocyanate, tetramethylxylylene diisocyanate Aromatic diisocyanates such as isocyanate and naphthalene diisocyanate are listed.

  Furthermore, a polyisocyanate compound having a valence of 3 or more is a dimer or a trimer of a polyisocyanate having a valence of 2 or more, a polyisocyanate having a valence of 3 or more, a polyhydric alcohol, a low molecular weight polyester resin, water, or the like. The free isocyanate group of an isocyanate compound having a free isocyanate group, such as an adduct obtained by reacting with an excess of isocyanate group, was blocked with a blocking agent such as phenols, oximes, lactams, alcohols, mercaptans, etc. A polyisocyanate having a biuret structure obtained by reacting block polyisocyanate or polyisocyanate having a free isocyanate group with water,

  Homopolymers of vinyl monomers having an isocyanate group, such as 2-isocyanatoethyl (meth) acrylate, 3-isopropenyl-α, α-dimethylbenzyl isocyanate or (meth) acryloyl isocyanate, or those containing isocyanate groups Isocyanates obtained by copolymerizing vinyl monomers with (meth) acrylic, vinyl ester, vinyl ether, aromatic vinyl or fluoroolefin vinyl monomers which can be copolymerized with these, respectively. Various vinyl copolymers such as a group-containing acrylic copolymer, vinyl ester copolymer or fluoroolefin copolymer can be used in combination.

  The blending ratio of the thermoplastic resin A and the polyisocyanate compound is preferably in the range of 0.5 to 1.5 equivalents of isocyanate groups in the polyisocyanate compound per equivalent of hydroxyl groups in the thermoplastic resin A. The range of 7-1.2 equivalent is preferable from the balance of the various performances of a cured coating film.

(Curing catalyst)
When the thermoplastic resin A and the polyisocyanate compound are reaction-cured, a known curing catalyst can be added as necessary.
Specifically, for example, N-methylmorpholine, pyridine, 1,8-diazabicyclo [5.4.0] undecene-7 (DBU), 1,5-diazabicyclo [4.3.0] nonene-5 ( DBN), 1,4-diazabicyclo [2.2.2] octane (DABCO),
Tri-n-butylamine or dimethylbenzylamine, butylamine, octylamine, monoethanolamine,

Diethanolamine, triethanolamine, imidazole, 1-methylimidazole, 2,4-dimethylimidazole, 1,4-diethylimidazole, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3- (N-phenyl) Various amine compounds such as aminopropyltrimethoxysilane, 3- (2-aminoethyl) aminopropyltrimethoxysilane, 3- (2-aminoethyl) aminopropylmethyldimethoxysilane,

Tetramethylammonium salt, tetrabutylammonium salt, trimethyl (2-hydroxylpropyl) ammonium salt, cyclohexyltrimethylammonium salt, tetrakis (hydroxylmethyl) ammonium salt, dilauryldimethylammonium salt, trioctylmethylammonium salt, o-trifluoromethyl Various quaternary ammonium salts such as phenyltrimethylammonium salt, and so-called quaternary ammonium salts having chloride, bromide, carboxylate, hydroxide, etc. as typical counter anions, dibutyltin dilaurate, dibutyl There are various organometallic compounds such as tin acetate, lead dioctylate and cobalt naphthenate.

  The addition amount of the curing catalyst is not particularly limited, but if it is added excessively, the pot life (pot life) is shortened and the composition containing the thermoplastic resin A and the polyisocyanate compound may be gelled. Usually, it is preferable to add 0.01 to 1 part of a curing catalyst to 1000 parts of the composition.

(Reaction rate of surface layer (A))
The surface layer (A) is semi-cured before molding in the range of an isocyanate reaction rate of 20 to 80%. Depending on conditions such as heating during the molding process, if the reaction rate is less than 20%, the curing reaction is insufficient, and the cured coating film may adhere to the mold due to heat during the molding process, causing mold contamination. On the other hand, if the reaction rate exceeds 80%, cracking or peeling may occur due to stretching during molding. The semi-curing conditions before molding are usually about 5 to 1 day in the range of 50 to 80 ° C. (50 ° C. is an example).
Since the surface layer (A) used in the decorative laminated sheet of the present invention has a secondary hydroxyl group and has almost no acid value, the reaction rate is very slow. Easy to rate. On the other hand, when the reaction temperature is 100 ° C. or higher, the reaction rate increases rapidly. The heater temperature during molding is usually 200 ° C. or higher, and in this case, the sheet temperature during molding is 100 ° C. or higher. Therefore, it can be almost cured under such normal molding conditions.
In the present invention, it is not essential that the isocyanate reaction rate of the surface layer (A) after coating molding is 100%. In general, in a thermosetting or UV curable paint or sheet, it is difficult to achieve a reaction rate of 100%, and the reaction reaches a peak at about 90% or more. If more energy is applied, the coating film may be deteriorated.
Therefore, normally (depending on the thing), it is designed so that the performance can be exhibited if a reaction rate of 90% or more is exhibited. The decorative laminated sheet of the present invention is the same, as long as it has reacted to such an extent that performance can be expressed, and usually the isocyanate reaction rate may be 90% or more.

  Here, the reaction rate refers to a test film in which the composition for the surface layer (A) is applied using a suitable transparent resin film, for example, a 25 μm PET film, and cured in the same manner as the actual drying / curing conditions. Two types of correction films that were completely cured (heat treatment at 110 ° C. for 2 hours) were prepared, and before and after curing of isocyanate functional groups by transmission method or ATR method using FT-IR (Fourier transform infrared spectrophotometer). The absorbance peak height of the IR spectrum is measured and obtained from the following formula.

(Transparent or translucent thermoplastic resin layer (B))
The transparent or translucent thermoplastic resin layer (B) used in the present invention is a transparent or translucent single layer or multilayer film, and is a resin layer that has spreadability by heating.
Specifically, a film mainly composed of a thermoplastic resin having a softening point in the range of 30 to 300 ° C. is preferable in order to perform a forming process by heating such as vacuum forming. For example, polyethylene, polypropylene, polyethylene terephthalate, polybutylene terephthalate, acrylic resin, silicone-acrylic resin, ionomer, polystyrene, polyurethane, nylon, ethylene-vinyl alcohol, polyvinyl chloride, polyvinylidene chloride, polyvinyl fluoride, polyvinylidene difluorate Polycarbonate resin or the like is preferably used. Among these, a film mainly composed of polyvinylidene difluorate, polycarbonate resin, or acrylic resin is preferable from the viewpoint of integral molding possibility and weather resistance. The thickness is not particularly limited, but is preferably in the range of 30 to 2000 μm, more preferably 50 to 500 μm, since the coating property of the ink protective layer is good.
Moreover, you may contain a coloring agent. Alternatively, additives such as a plasticizer, an antioxidant, an ultraviolet absorber, an antistatic agent, a flame retardant, and a lubricant may be blended as long as the impact strength and moldability are not impaired. Two or more types may be used in combination.

(Ink layer (C))
The ink layer (C) used in the present invention is not particularly limited, and general-purpose ink can be used. If the ink film thickness is too thin, the concealability tends to be inferior and the design properties tend to be impaired. If it is too thick, the orientation of the metal pieces may be disturbed when using the high-brightness ink described below. For this reason, as a film thickness of an ink layer, 5 micrometers or less are preferable, 0.05-5 micrometers is more preferable, Especially preferably, it is 0.5-3 micrometers.
Among these, when a mirror-like metallic glossy ink (hereinafter referred to as high-brightness ink) containing metal thin film strips is used, a molded product having a mirror-like metallic gloss can be obtained.
It is preferable that content with respect to the non volatile matter in the ink of a metal thin film piece is the range of 3-60 mass%. High-gloss inks using thin metal film strips are aligned with the metal thin film strips parallel to the surface of the object when the ink is printed or applied. Unobtainable high-brightness mirror-like metallic luster is obtained.

(Metal thin film strip)
Aluminum, gold, silver, copper, brass, titanium, chrome, nickel, nickel chrome, stainless steel, etc. can be used as the metal of the metal thin film strip used in the high gloss ink used in the ink layer. As a method for making a metal into a thin film, in the case of a metal having a low melting point such as aluminum, it is a foil if it has malleability, such as aluminum, gold, silver, copper, etc. , Sputtering and the like. Among these, the metal thin film strip obtained from the vapor deposition metal thin film is preferably used. The thickness of the metal thin film is preferably 0.01 to 0.1 μm, more preferably 0.02 to 0.08 μm. The size in the surface direction of the thin metal thin film dispersed in the ink is preferably 5 to 25 μm, more preferably 10 to 15 μm. When the size is less than 5 μm, the brightness of the coating film becomes insufficient, and when it exceeds 25 μm, the metal thin film strips are difficult to orient and decrease in brightness, and ink is printed or applied by gravure or screen printing. Doing so will cause clogging of the plate.

(Supporting substrate layer (D))
The support base material layer (D) used in the present invention is preferably a film mainly composed of a thermoplastic resin having a softening point in the range of 30 to 300 ° C. in order to perform a molding process. Examples of such thermoplastic resins include acrylonitrile / butadiene / styrene (ABS) resin, acrylonitrile / acrylic rubber / styrene (AAS) resin, acrylonitrile / ethylene rubber / styrene (AES) resin, polyethylene (PE) resin, General-purpose resins such as polypropylene (PP) resin, vinyl chloride (PVC) resin, olefin elastomer (TPO), vinyl chloride elastomer (TPVC), styrene elastomer (SBC), urethane elastomer (TPU), polyester Thermoplastic elastomers (TPE) such as elastomer (TPEE) and polyamide-based elastomer (TPAE) can be used. Among these, when obtaining a molded body having a complicated shape typified by automobile exterior parts, polypropylene resin, polyethylene resin, blended products thereof, AAS resin, and ABS resin are excellent because of excellent formability. Etc. are more preferably used. These resins may contain rubber modifiers such as EPR, SBS, SEBS for the purpose of improving impact strength and the like. Although the thickness is not particularly limited, the thickness of the support base material layer is preferably 10 μm to 2000 μm.

The laminated sheet for molding of the present invention is thermoformed to form a three-dimensional shaped molded body. At this time, when the molding shrinkage of the thermoplastic resin used for the supporting base material layer (D) and the transparent or translucent thermoplastic resin layer (B) is different, the molded body may be deformed. In this case, it is preferable to add an inorganic filler to the support substrate layer (D), the molding shrinkage rate can be controlled to be small, and the difference in molding shrinkage rate between the support substrate layer and the ink layer can be reduced.
The type of the inorganic filler is not particularly limited, and examples thereof include talc, calcium carbonate, clay, diatomaceous earth, mica, magnesium silicate, silica and the like. The average particle diameter is preferably 4 μm or less, more preferably 2 μm or less. If the particle size of the inorganic filler is too large, unevenness may occur on the surface of the support base layer, and the unevenness may also affect the ink layer laminated thereon. In particular, the ink layer (C) is a highly bright ink. In such a case, the orientation of the metal thin film strip may be disturbed.
The amount of the inorganic filler added to the resin of the support base material layer (D) is preferably 5% by mass to 60% by mass from the viewpoint of the balance between molding processability and molding shrinkage.

In addition, it is preferable that the supporting base material layer (D) contains a colorant because the concealability of the base color of the molded body is improved. The colorant to be used is not particularly limited, and conventional inorganic pigments, organic pigments and dyes used for coloring general thermoplastic resins can be used according to the intended design. For example, inorganic pigments such as titanium oxide, titanium yellow, iron oxide, complex oxide pigments, ultramarine, cobalt blue, chromium oxide, bismuth vanadate, carbon black, zinc oxide, calcium carbonate, barium sulfate, silica, talc; azo Pigments, phthalocyanine pigments, quinacridone pigments, dioxazine pigments, anthraquinone pigments, isoindolinone pigments, isoindoline pigments, perylene pigments, perinone pigments, quinophthalone pigments, thioindigo pigments and diketopyrrolo Organic pigments such as pyrrole pigments; metal complex pigments and the like. In addition, it is preferable to use one or two dyes mainly selected from the group of oil-soluble dyes.
The amount of colorant added to the base material layer varies depending on the type of colorant and the desired thickness and color tone of the sheet, but in order to ensure the concealment of hue and background color and maintain impact strength The content of the colored layer is preferably in the range of 0.1 to 20% by mass and more preferably in the range of 0.5 to 15% by mass. When the colorant is added in excess of 20% by mass, the impact strength is lowered, and when the amount of the colorant added is less than 0.1%, there is a tendency that the hiding property of the hue and the background color is not sufficient.

(Ink protective layer)
When the ink layer (C) uses high-brightness ink, between the ink layer (C) and the transparent or translucent thermoplastic resin layer (B), heat resistance, solvent resistance, One or more ink protective layers may be provided for the purpose of improving design properties, weather resistance, and the like. Among them, an ink protective layer composed of a cross-linked layer made of a thermosetting composition is preferable because of good ink solvent resistance and heat resistance during molding. Although there is no restriction | limiting in particular unless it inhibits, Acrylic resin is preferable from points, such as the ease of adjustment of a crosslinking density, a weather resistance, and adhesiveness with a transparent thermoplastic film. There are no particular restrictions on the crosslinking mechanism, and in the case of acrylic resins, UV curing, EB curing, hydroxyl group-containing vinyl copolymer / isocyanate curing, silanol / water curing, epoxy / amine curing, etc. can be used. From the viewpoints of easiness, weather resistance, reaction rate, presence or absence of reaction byproducts, production cost, etc., hydroxyl group-containing vinyl copolymer / isocyanate curing is preferable.
The ink protective layer can be a colored layer in order to impart design properties. In this case, the amount of the colorant added varies depending on the type of the colorant, the target color tone and the thickness of the protective layer, but the total light transmittance of the protective layer is 20 so as not to conceal the ink layer having a specular metallic luster. % Or more, and the total light transmittance is more preferably 40% or more.

  As the colorant, a pigment is preferable. The pigment to be used is not particularly limited, and known and commonly used pigments such as colored pigments, metallic pigments, interference color pigments, fluorescent pigments, extender pigments and rust preventive pigments can be used.

  Examples of the color pigment include quinacridone series such as quinacridone red, azo series such as pigment red, phthalocyanine series organic pigments such as phthalocyanine blue, phthalocyanine green and perylene red; and inorganic pigments such as titanium oxide and carbon black. Examples of the metallic pigment include aluminum powder, nickel powder, copper powder, brass powder, and chromium powder.

  Examples of interference color pigments include pearlescent pearl mica powder and pearlescent colored pearl mica powder, and fluorescent pigments include quinacridone, anthraquinone, perylene, perinone, and diketopyrrolopyrrole. , Isoindolinone, condensed azo, benzimidazolone, monoazo, insoluble azo, naphthol, flavanthrone, anthrapyrimidine, quinophthalone, pyranthrone, pyrazolone, thioindigo, anthanthrone, dioxazine , Organic pigments such as phthalocyanine and indanthrone, metal complexes such as nickel dioxin yellow and copper azomethine yellow, metal oxides such as titanium oxide, iron oxide and zinc oxide, barium sulfate and calcium carbonate Metal salt, carbon black, aluminum Inorganic pigments fine mica.

(Method for producing decorative laminated sheet)
The decorative laminated sheet of the present invention is obtained by sequentially laminating an ink layer (C), a transparent or translucent thermoplastic resin layer (B), and a surface layer (A) on the support base layer (D). obtain. It is preferable to provide an adhesive layer or a pressure-sensitive adhesive layer between the support base layer (D) and the ink layer (C). The adhesive or the pressure-sensitive adhesive can be formed into a laminated sheet by a dry lamination method, a wet lamination method, a hot melt lamination method, or the like.

Components constituting the adhesive include conventional phenol resin adhesives, resorcinol resin adhesives, phenol-resorcinol resin adhesives, epoxy resin adhesives, urea resin adhesives, polyurethane adhesives and polyaromatics. Type thermosetting resin adhesives, reactive adhesives using ethylene unsaturated carboxylic acid, etc., vinyl acetate resin, acrylic resin, ethylene vinyl acetate resin, polyvinyl alcohol, polyvinyl acetal, vinyl chloride, nylon and cyano Examples thereof include thermoplastic adhesives such as acrylate resins, rubber adhesives such as chloroprene adhesives, nitrile rubber adhesives, SBR adhesives, and natural rubber adhesives. In particular, an acrylic urethane adhesive is preferred because the adhesiveness between the acrylic resin and the polypropylene resin is good and the followability of elongation during vacuum forming is good.
As the adhesive, acrylic, rubber, polyalkyl silicon, urethane, polyester, etc. are preferably used.

  For these coatings, a gravure coater, a gravure reverse coater, a flexo coater, a blanket coater, a roll coater, a knife coater, an air knife coater, a kiss touch coater, a comma coater, or the like can be used.

The application amount of the adhesive or pressure-sensitive adhesive is preferably in the range of 0.1 to 30 g / m ² , particularly preferably ² to 10 g / m ² . When the amount is less than 2 g / m ² , the adhesive strength is weakened. When the amount is more than 10 g / m ² , the drying property is lowered and the appearance tends to be poor. The thickness of the adhesive layer is preferably in the range of 0.1 to 30 μm, more preferably 1 to 20 μm, and particularly preferably 2 to 10 μm.

  In addition, for the purpose of improving the affinity with the adhesive, the adhesion surface of the support base material layer is a surface treatment such as plasma treatment, corona treatment, flame treatment, electron beam irradiation treatment, roughening treatment, ozone treatment, A dry plating process such as vacuum deposition, sputtering, or ion plating may be performed.

  The lamination method of the ink layer (C), the transparent or translucent thermoplastic resin layer (B), and the surface layer (A) may be performed by a known printing or coating method. For example, gravure printing, flexographic printing, screen Printing methods such as printing, gravure coater, gravure reverse coater, flexo coater, blanket coater, roll coater, knife coater, air knife coater, kiss touch coater, kiss touch reverse coater and comma coater, comma reverse coater, micro gravure coater, etc. A construction method can be used.

(Method for manufacturing coated molded products)
The decorative laminated sheet of the present invention can be used as a surface layer in various molding methods. Specifically, after the decorative laminated sheet of the present invention is brought into close contact with the mold surface, a molding resin is supplied to the mold to produce a coated molded product.
For example, when preform molding is performed after preform molding (vacuum molding and match molding), when using only a male mold, the clear hardened layer is the opposite surface of the mold, and the support base material layer is the mold surface. After installation, if only female mold is used, install the male mold and female mold so that the clear hardened layer is opposite to the male mold and the support base layer is opposite to the mold. In the case of using both, the support base material layer (D) is disposed on the mold surface, and then formed into a molded body having a three-dimensional shape by thermoforming. The temperature at the time of thermoforming, that is, the sheet temperature when the decorative laminate sheet is brought into close contact with the mold surface is preferably 100 ° C. or higher, and the secondary hydroxyl group and the isocyanate group are reacted at once. Can do.
Next, it can be molded by an insert injection molding method in which it is inserted into the female mold side in the injection mold and integrated with the injection resin.

(Vacuum forming)
The mold used in the vacuum forming method is not particularly limited, but only the male mold can be used, only the female mold can be used, and both the male mold and the female mold can be used. Depending on the mold, it can be used properly. This forming method will be described when a male mold is used. A sheet heated in a heating zone using hot air, an electric heater, a far-infrared ceramic heater or the like is matched with a male mold, and the sheet heated with the mold is heated. In order to make it adhere | attach, it shape | molds by performing vacuum suction from the vacuum port of a metal mold | die. By performing the main molding at a relatively high temperature, it is possible to form a molded body that retains a mirror-like metallic luster excellent in deep drawability by three-dimensional solid molding.
The setting conditions for vacuum forming are not particularly limited as long as the mold reproducibility of the molded body is good, but when a far infrared heater is used, the heater temperature is 200 to 500 ° C., and the indirect heating time is 5 to 5. Heating is performed in about 30 seconds so that the sheet temperature becomes 100 ° C. or higher. In addition, the mold temperature needs to be determined while confirming the appearance and the degree of shrinkage of the molded body. However, in the sheet heating temperature region, the sheet rigidity is low and the sheet is easily stretched. The vacuum / cooling time is preferably 5 to 100 seconds.

(Match mold molding)
Match mold molding is performed by matching a female mold with a male mold so as to sandwich a sheet heated in a heating zone. The mold used here is usually provided with a vacuum port as an escape path for air in the mold, but vacuum suction may be performed supplementarily using this hole. By performing this match mold molding at a low temperature, it is possible to mold a molded body maintaining a mirror-like metallic luster having a high brightness similar to that of the sheet before molding.

  As for the setting conditions of match mold molding, when a far-infrared heater is used, heating is performed at a heater temperature of 200 to 500 ° C. and an indirect heating time of about 5 to 30 seconds. The sheet to be heated is usually set to have a sheet temperature of 100 ° C. or higher. When using a high-brightness ink as the ink layer (C), a method for measuring the transition temperature of the plastic shown in JISK7121 of the thermoplastic resin layer (B) so as to obtain a molded product having a high-brightness specular metallic luster is obtained. It is preferable that it becomes glass transition temperature +20 degreeC measured by this, More preferably, it is this glass transition temperature +10 degreeC. In addition, since the mold reproducibility of the molded article is improved, the lower limit temperature of the heated sheet is preferably the glass transition temperature of −15 ° C. or higher, more preferably the glass transition temperature or higher. In this temperature range, the sheet has high rigidity and is difficult to stretch, so care must be taken not to drag the sheet into the mold with a strong clamping force. The mold temperature needs to be determined while confirming the appearance and the degree of shrinkage of the molded body, and is preferably 20 to 120 ° C. The cooling time by the match mold is preferably 5 to 600 seconds.

(Insert molding)
In insert molding, the obtained preform molded body is placed in a mold so that the clear cured layer side is in contact with the female mold surface, and the base material layer and the adhesive layer are adhered to the supporting base material layer surface of the preform molded body. A thermoplastic resin is integrally formed by injection molding. The resin temperature of the injection resin is not particularly limited, but is preferably about 180 to 250 ° C. at which injection is possible as long as it is a thermoplastic resin such as polypropylene resin or ABS resin. The mold temperature is preferably about 20 to 80 ° C. for both the male mold and the female mold. However, when warping or the like occurs in the injection molded body, it is possible to correct the temperature by adding a temperature gradient to the male mold and the female mold. I can do it.

(Specular metallic luster and gloss retention)
The decorative laminated sheet of the present invention can maintain the gloss value of the thermoformed laminated sheet before molding at a high level. When the ratio (%) of the gloss value measured by the above-mentioned method to the gloss value of the laminated sheet for thermoforming before molding is defined as the gloss value retention rate, it is preferably 60% or more in the molding method of the present invention. Can be obtained. More preferably, 80% or more can be obtained.

  Hereinafter, the present invention will be described with specific examples, but the present invention is not limited thereto. In addition, the physical-property evaluation in an Example and a comparative example was performed with the following measuring method or test method. In the examples, “part” and “%” are both based on mass.

(Glossiness evaluation method for decorative laminated sheets before molding)
The gloss value of the decorative laminated sheet before molding was determined by a 20 ° gloss measurement method in accordance with JIS-K7105, with an incident angle of 20 ° and a light receiving angle of 20 °. In addition, Nippon Denshoku VGS-300A was used for the gloss meter.

(Brightness and gloss value evaluation method for molded products)
The brightness of the molded product with the clear cured layer of the decorative laminated sheet as the surface is determined by using a measurement method based on JIS-K7105 as the gloss value of the 20 ° gloss of the top surface of the trapezoidal molded product molded by the match mold molding method. The determination was made as follows.
The trapezoidal mold used in the evaluation has a female mold having a frontage of 120 × 90 mm, a bottom 66 × 51.7 mm and a depth of 25 mm, and a male mold having a frontage of 120.3 × 90.5 mm and a bottom 66 .Times.5.times.52.3 mm and depth 25 mm. During match molding, both male and female molds were used. The decorative laminated sheet was disposed so that the clear cured layer was in contact with the female mold surface. Evaluation was performed with the convex surface on the clear cured layer side of the obtained trapezoidal shaped body as the top surface. The expansion rate of the top surface was about 110%. The expansion rate here is expressed as 150% when the entire area is 1.5 times the original area. Further, the gloss retention is defined as a ratio (%) calculated by the following formula based on the gloss value obtained by measuring the molded product after molding with respect to the gloss value of the decorative laminated sheet before molding.

A: A gloss retention of 80% or more with respect to the gloss value of the decorative laminated sheet before molding.
A: A gloss retention of 60% or more with respect to the gloss value of the decorative laminated sheet before molding.
X: The gloss retention of less than 60% with respect to the gloss value of the decorative laminated sheet before molding.

(Maximum unfolding rate evaluation method for decorative laminated sheets)
The maximum expansion ratio of the decorative laminated sheet was measured by forming the decorative laminated sheet by a vacuum forming method and using the surface magnification as the expansion ratio. As the vacuum forming machine, a small vacuum forming machine “FE38PH” manufactured by Hermis Co., Ltd. was used.
Heat the clear hardened layer surface on the front side of the decorative laminated sheet with a heater, and after evacuating the heater, lift the square-box shaped female mold from the opposite side of the heater, press against the sheet and pull the vacuum to support the sheet The surface on the layer side was brought into close contact with the mold surface, and after cooling and solidification, a molded body was produced.
Using a female die (square body shape) of the following size, the development rate when the surface layer (A) in the center of the bottom of the molded body is free from cracks and peeling is 150%, 200%, Expressed as 250% and 300%.

Deployment rate Entrance size Depth Bottom size 150% 161 × 154mm 40mm 125 × 120mm
200% 166 × 159 55 125 × 120
250% 166 x 159 70 125 x 120
300% 169 x 163 75 125 x 120

  The expansion rate was expressed as 200% when the entire area was doubled compared to the original area. (For example, when a molded body having a thickness of 100 has a thickness 50 after molding, the molded body area after molding is doubled to 200% surface magnification (thickness measurement portion).)

A: The expansion ratio is 300% or more, and the top coat layer does not crack or peel.
A: The expansion ratio is 250% or more, and the topcoat layer has no cracks or peeling.
(Triangle | delta): The expansion ratio is 200% or more, and there is no crack or peeling in a topcoat layer.
X: The expansion ratio is 150% or more, and the topcoat layer has no cracks or peeling.
XX: Deployment magnification is less than 150%.

(Abrasion resistance)
The surface layer (A) side of a test piece cut out to a length of 5 cm and a width of 2 cm from the molded product produced in the same manner as in the above “evaluation of luminance of molded product” was 300 times with a friction / abrasion tester at a load of 500 g. After rubbing (# 0000 steel wool), the dirt on the surface layer (A) was wiped off with absorbent cotton and the gloss value (20 ° gloss) was measured to determine the gloss retention before and after the test. Scratch resistance was judged from the gloss retention.

◎: Gloss retention is 95% or more, gloss is present, and scratches are hardly noticeable ○: Gloss retention is less than 95% to 85% or more, gloss is slightly lowered and some scratches are observed Δ: Gloss retention is Less than 85% to 75 or more, gloss is reduced and scratches are noticeable x: Gloss retention (%) where gloss retention is less than 75% and gloss is significantly reduced and many scratches are noticeable = (of the molded product after the test) Gloss value / Gloss value of decorative laminate sheet before test) × 100

(Solvent resistance)
Using a rubbing tester (manufactured by Ohira Rika Kogyo Co., Ltd.), a test piece cut out to a length of 5 cm and a width of 5 cm from the molded body produced in the same manner as in the above-mentioned “luminance evaluation of molded body” is placed on the surface layer (A) side. After xylene was sufficiently infiltrated into absorbent cotton, it was placed on it, held on a testing machine terminal, reciprocated 10 times with a load of 1 kg, and then the surface layer (A) was visually evaluated and determined as follows.

○: No change in gloss of surface layer (A) Δ: Gloss of surface layer (A) is low and scratched ×: Gloss of surface layer (A) is extremely low and scratches are conspicuous

(Acid resistance)
0.4 ml of 5% sulfuric acid aqueous solution was dropped in the form of a spot on the surface layer (A) of a test piece cut out to a length of 5 cm and a width of 5 cm from a molded body produced in the same manner as in the above “evaluation of luminance of molded body”. After heating at 80 ° C. for 30 minutes with a dryer, the surface was washed and dried, and the surface of the surface layer (A) was visually evaluated and determined as follows.
○: No change in the surface layer (A) Δ: Some spot marks are observed in the surface layer (A) ×: Changes in spot marks, spots, whitening, swelling, etc. are observed in the surface layer (A)

(Adhesion)
A flat portion was appropriately cut out from the molded body produced in the same manner as in the above “evaluation of luminance of molded body” to obtain a test piece. The test was conducted according to a cross-cut tape peeling method (JIS K5400). After the test, the number of missing eyes in the squares of the surface layer (A) was counted and determined as follows.

◯: No omission in the cell of the surface layer (A) is observed Δ: The number of omission of the cell in the surface layer (A) is less than 10% ×: The number of omission of the cell in the surface layer (A) is 10 % Or more allowed

(Reaction rate of the surface layer (A) of the sheet)
The reaction rate was determined by applying the resin composition for the surface layer (A) to a PET film having a thickness of 25 μm using a bar coater # 30, placing it in a 60 ° C. drier for 1 minute, and drying it. Two types are prepared: a film (F1) cured under the curing conditions of the clear cured layer described in 1 and 2, and a correction film (F2) obtained by completely curing the resin composition (110 ° C./2 hours heat treatment). did.
The absorbance peak height of the IR spectrum before and after curing of the isocyanate functional group was measured by a transmission method or ATR method using FT-IR (Fourier transform infrared spectrophotometer), and the reaction rate was determined from the following formula.

(However, in the above formula, “absorbance peak height for pre-curing test” represents the peak height of absorbance in a state where the resin composition for the surface layer (A) is applied and dried by solvent, “Absorption peak height for post-correction” represents the peak height of absorbance of the correction film (F2), and “Absorption peak height for post-curing test” represents the peak height of absorbance of the film (F1). To express.

(Preparation of decorative laminated sheet)
Production Examples 1 to 4 Production examples of a thermoplastic resin that is a component of the surface layer (A).
Production Examples 5 to 8 Production examples of thermoplastic resins for comparison of the components of the surface layer (A).
Number average molecular weight: Indicates a polystyrene equivalent value of the GPC measurement result.
Nonvolatile content: 1 g of a sample was precisely weighed on an aluminum dish, spread thinly and uniformly with toluene, air-dried, further dried in a hot air dryer at 108 ° C. for 1 hour, and determined from the weight before and after drying.
The hydroxyl value was calculated as the KOH neutralization amount from the charged composition of the hydroxyl group-containing monomer. The Tg of the surface layer (A) was measured by DSC method, and the acid value was measured by 0.05 mol / liter potassium hydroxide-toluene solution titration method.

(Production Example 1) Synthesis of a resin (A-1) having a secondary hydroxyl group of 100 mol% and an acid value of 0.1 or less 3 L equipped with a temperature controller, nitrogen introduction pipe, dropping device (2 units), and stirring device In a reaction vessel, 400 parts of ethyl acetate was charged, and after replacing with nitrogen, the temperature was raised to 75 ° C. Separately, a solution in which 446 parts of methyl methacrylate, 164.5 parts of n-butyl methacrylate, and 89.6 parts of 2-hydroxypropyl methacrylate (100 mol% of secondary hydroxyl group) are well mixed (hereinafter referred to as a monomer solution). And 70 parts of ethyl acetate, 3 parts of perbutyl O (trade name, manufactured by Nippon Oil & Fats Co., Ltd.), 3 parts of ABN-V (trade name, manufactured by Nippon Hydrazine Industry Co., Ltd.), ABN-E (trade name, manufactured by Nippon Hydrazine Industry Co., Ltd.) A solution in which 3 parts were mixed well (hereinafter referred to as catalyst solution) was charged into a dropping device and immediately replaced with nitrogen.
The monomer solution and the catalyst solution were respectively added dropwise to the reaction vessel over 4 hours in a nitrogen atmosphere. During the charging, the dropping rate of the monomer solution and the catalyst solution was adjusted so that there was no sudden rise in reaction temperature. After completion of dropping, the mixture was stirred and held for about 2 hours, and 233 parts of ethyl acetate was charged. After the preparation, the stirring was further held for 10 hours to complete the reaction, and a resin (A-1) having a nonvolatile content of 50% was obtained. The solid content of the obtained resin had a number average molecular weight of 18,600, a hydroxyl group equivalent of 50, an acid value of 0.1 or less, and a calculated Tg of 70 ° C.

(Production Example 2) Synthesis of Resin (A-2) with Secondary Hydroxyl Group of 70 mol% and Acid Value of 0.6 The solvent used is methyl isobutyl ketone (MIBK), the monomer solution is 494.7 parts of methyl methacrylate, 117 parts 2-ethylhexyl methacrylate, 63 parts 2-hydroxypropyl methacrylate (70 mol% secondary hydroxyl group) 24.5 parts 2-hydroxyethyl methacrylate (30 mol% primary hydroxyl group), 0.7 methacrylic acid It manufactured like the manufacture example 1 except using a part. As a property of the reaction product, a resin (A-2) having a nonvolatile content of 50% was obtained. In the solid content of the obtained resin, the number average molecular weight was 20,500, the hydroxyl group equivalent was 50, the acid value was 0.6, and the calculated Tg was 70 ° C.

(Production Example 3) Synthesis of Resin (A-3) whose Secondary Hydroxyl Group is 100% by mole and whose Acid Value is 0.6 The solvent used is butyl acetate, the monomer solution is 470.4 parts of methyl methacrylate, and methacrylic acid tertiary. Butyl 85.4 parts, 2-hydroxypropyl methacrylate 143.5 parts (secondary hydroxyl group is 100 mol%) The same as Production Example 1 except that 0.7 parts of methacrylic acid is used and the reaction temperature is 85 ° C. Manufactured. As a property of the reaction product, a resin (A-3) having a nonvolatile content of 50% was obtained. In the solid content of the obtained resin, the number average molecular weight was 15,200, the hydroxyl group equivalent was 80, the acid value was 0.6, and the calculated Tg was 85 ° C.

(Production Example 4) Synthesis of Resin (A-4) whose Secondary Hydroxyl Group is 100 mol% and Acid Value is 0.6 The solvent used is butyl acetate, the monomer solution is 331 parts of methyl methacrylate, and 2-ethylhexyl methacrylate is 278. .5 parts, 2-hydroxypropyl methacrylate 89.6 parts (secondary hydroxyl group is 100 mol%) As in Production Example 1, except that 0.7 parts of methacrylic acid is used and the reaction temperature is 85 ° C. Manufactured. As a property of the reaction product, a resin (A-4) having a nonvolatile content of 50% was obtained. In the solid content of the obtained resin, the number average molecular weight was 21,000, the hydroxyl group equivalent was 50, the acid value was 0.6, and the calculated Tg was 40 ° C.

(Production Example 5) Synthesis of Resin (A-5) whose Secondary Hydroxyl Group is 0 mol% and Acid Value is 0.1 or Less Monomer solution is 410.6 parts of methyl methacrylate, 204.7 parts of n-butyl methacrylate, methacryl Production was carried out in the same manner as in Production Example 1 except that 81.2 parts of acid 2-hydroxyethyl (primary hydroxyl group was 100 mol%) was used. As a property of the reaction product, a resin (A-5) having a nonvolatile content of 50% was obtained. In the solid content of the obtained resin, the number average molecular weight was 21,800, the hydroxyl group equivalent was 50, the acid value was 0.1 or less, and the calculated Tg was 70 ° C.

(Production Example 6) Synthesis of Resin (A-6) having Secondary Hydroxyl Group of 30 mol% and Acid Value of 3.2 The solvent used is butyl acetate, the monomer solution is 488.3 parts of methyl methacrylate, 2-methacrylic acid 2- 127.7 parts of ethylhexyl, 56.7 parts of 2-hydroxyethyl methacrylate (70 mol% primary hydroxyl group) 26.6 parts of 2-hydroxypropyl methacrylate (30 mol% secondary hydroxyl group) 3.5 parts of methacrylic acid Was used in the same manner as in Production Example 1 except that the reaction temperature was 85 ° C. As a property of the reaction product, a resin (A-6) having a nonvolatile content of 50% was obtained. In the solid content of the obtained resin, the number average molecular weight was 16,200, the hydroxyl group equivalent was 50, the acid value was 3.2, and the calculated Tg was 70 ° C.

(Production Example 7) Synthesis of Resin (A-7) with Secondary Molecule of 0 Mole% and Acid Value of 6.6 The solvent used is butyl acetate, the monomer solution is 462 parts of methyl methacrylate, and tertiary butyl methacrylate 103 .4 parts, 2-hydroxyethyl methacrylate 128 parts (primary hydroxyl group is 100 mol%) Manufactured in the same manner as in Production Example 1 except that 6.6 parts of methacrylic acid was used and the reaction temperature was 80 ° C. . As a property of the reaction product, a resin (A-7) having a nonvolatile content of 50% was obtained. In the solid content of the obtained resin, the number average molecular weight was 20,200, the hydroxyl group equivalent was 80, the acid value was 6.6, and the calculated Tg was 95 ° C.

(Production Example 8) Synthesis of Resin (A-8) with Secondary Molecule of 0 Mole% and Acid Value of 3.2 Monomer solution is 279 parts of methyl methacrylate, 288 parts of 2-ethylhexyl methacrylate, 2-hydroxy methacrylate 129.5 parts of ethyl (primary hydroxyl group is 100 mol%) Production was carried out in the same manner as in Production Example 1 except that 3.5 parts of methacrylic acid was used. As a property of the reaction product, a resin (A-8) having a nonvolatile content of 50% was obtained. In the solid content of the obtained resin, the number average molecular weight was 22,500, the hydroxyl group equivalent was 80, the acid value was 3.2, and the calculated Tg was 40 ° C.

(Examples 1-6, Comparative Examples 1-7)
(Composition for surface layer (A))
Using the resin compositions (A-1) to (A-8) obtained in Production Examples 1 to 8, compositions for the surface layer (A) were prepared. Each component is listed in Tables 1 and 2.

(Thermoplastic resin (B))
As the thermoplastic resin (B), a rubber-modified PMMA film (B-1) having a transparent surface gloss value of 140%, a pencil hardness of H, a Tg of 104 ° C. (JISK7121), and a thickness of 125 μm was used.

(Ink for ink layer (C))
(Aluminum thin film strip for ink)
Nitrocellulose (HIG7) was dissolved in a mixed solvent of ethyl acetate: isopropyl alcohol = 6: 4 to make a 6% solution. The solution was applied onto a polyester film with a gravure plate having a screen line number of 175 lines / inch and a cell depth of 25 μm to form a release layer. After sufficiently drying, aluminum is vapor-deposited on the release layer to a thickness of 0.04 μm, and the same nitrocellulose solution as that used for the release layer is applied to the deposited film surface under the same conditions as in the release layer. The top coat layer was formed by coating.
The deposited film is immersed in a mixed solvent of ethyl acetate: isopropyl alcohol = 6: 4 to peel the aluminum deposited film from the polyester film, and then the aluminum deposited film is pulverized with a stirrer so that the size becomes about 150 μm. An aluminum thin film strip was prepared.

(Aluminum thin film slurry for ink)
Aluminum thin film strip 10 parts Ethyl acetate 35 parts Methyl ethyl ketone 30 parts Isopropyl alcohol 30 parts The above mixture was stirred and 5 parts of nitrocellulose solution having the following composition was added.
Nitrocellulose (HIG 1/4) 25%
Ethyl acetate: isopropyl alcohol = 6: 4 mixed solvent 75%
While maintaining the temperature at 35 ° C. or lower, the above mixture is stirred using a turbo mixer until the size of the aluminum thin film pieces becomes 5 to 25 μm, thereby preparing an aluminum thin film piece slurry (nonvolatile content 10%). did.

(Ink preparation)
Aluminum thin film slurry (non-volatile content 10%) 30 parts Binder resin Carboxylic acid-containing PVC-vinyl acetate resin 3 parts
("Vinylite VMCH" manufactured by UCC)
Carboxylic acid-containing urethane resin 7 parts (Dainippon Ink & Chemicals "Taiho Force NT810-45" nonvolatile content 45%)
Ethyl acetate 23 parts Methyl ethyl ketone 26 parts Isopropanol 10 parts The above was mixed to prepare ink (C-1) having an aluminum thin film strip concentration of 35 mass% in the nonvolatile content.

(Adjustment of thermosetting resin solution for ink protective layer)
850 parts of butyl acetate and 1 part of perbutyl Z (trade name, manufactured by NOF Corporation, t-butyl peroxybenzoate) are added to a reaction vessel equipped with a temperature controller, a nitrogen introducing tube, a dropping device (2 units), and a stirring device. After charging and nitrogen substitution, the temperature was raised to 110 ° C. over 1.5 hours.
Separately, 660 parts of methyl methacrylate, 148 parts of tertiary butyl methacrylate, 183 parts of 2-hydroxyethyl methacrylate and 4.5 parts of methacrylic acid were mixed well with 200 parts of isobutyl acetate, perbutyl O (product) Name, Nippon Oil & Fat Co., Ltd., t-butyl peroxy-2-ethylhexanoate) 9 parts, Perbutyl Z (trade name, Nippon Oil & Fats Co., Ltd., t-butyl peroxybenzoate) 2 parts well mixed solution Each of these catalyst solutions was charged into a dropping apparatus and immediately purged with nitrogen.
Under a nitrogen atmosphere, the monomer solution and the catalyst solution described above were dropped into the reaction vessel over 5 hours while adjusting the feed rate so that the reaction temperature did not increase rapidly. As a result of continuing stirring for about 15 hours after the completion of dropping, a resin composition having a nonvolatile content of 60% was obtained. In the solid content of the obtained resin, the number average molecular weight was 500,000, the hydroxyl value was 79 KOHmg / g, the acid value was 3.59 KOHmg / g, and the calculated Tg was 95 ° C.

  The equivalent number of hydroxyl groups in the above-mentioned hydroxyl group-containing vinyl copolymer and the polyisocyanate compound “URNOCK DN-981 (trade name, manufactured by Dainippon Ink & Chemicals, Inc., isocyanurate ring-containing polyisocyanate, number average molecular weight of about 1000, non-volatile 75% (solvent: ethyl acetate (EtAc), functional group number 3, NCO concentration 13.7%)) is a ratio in which the equivalent number of isocyanate groups is 0.8 to 1.2: 0.8 to 1.2 Were mixed and mixed to prepare a thermosetting resin solution (P-1) for an ink protective layer.

(adhesive)
Two-component polyester urethane adhesive (two-component mixed adhesive of “LX-630PX” and its curing agent “KR-90” manufactured by Dainippon Ink & Chemicals, Inc.) is mixed at a weight ratio of 42: 1. The adhesive was adjusted.

(Supporting substrate layer (D))
Random PP (Noblen FS3611) manufactured by Sumitomo Chemical Co., Ltd. was introduced from the extruder hopper as a supporting base material layer, extruded from a T die at a processing temperature of 200 ° C., passed through a cast roll heated to 40 ° C., and then wound. The unstretched original fabric sheet (D-1) was manufactured.

(Examples 1-6 and Comparative Examples 1-7)
(Method for creating decorative laminated sheet)
Applying the composition (A-1) to (A-8) for the surface layer (A) to the thermoplastic resin (B-1) film using a micro gravure coater so as to have a dry film thickness of 15.0 μm, After drying, semi-curing treatment was performed with a hot air drier according to the curing conditions described in Tables 1 and 2 to obtain a surface layer (A).
Next, a thermosetting resin solution (P-1) serving as an ink protective layer is applied to the thermoplastic resin (B-1) film opposite to the surface having the surface layer (A) so as to have a dry film thickness of 2 μm. Worked and dried. After coating, it was placed in a hot air dryer at 50 ° C. for 4 days to be cured to obtain an ink protective layer.
On the ink protective layer, the ink (C-1) for the ink layer (C) was applied using a gravure coater so as to have a dry film thickness of 1 μm.
The adhesive surface of the support base material layer (D-1) was subjected to corona treatment, and the adhesive was applied using a bar coater # 20. The ink layer (C-1) and the support base layer (D-1) are laminated together using a rubber roll laminator set at 40 ° C, and immediately put in a hot air dryer at 50 ° C for 3 days to cure the adhesive. went.
In the present invention, the surface layer (A) / thermoplastic resin (B) film / ink protective layer / ink layer (C) / adhesive layer / supporting substrate layer (D) with a thickness of about 430 μm is used for decoration. A laminated sheet was produced.

(Match mold molding)
After clamping the obtained laminated sheet for decoration using a small vacuum forming machine of FE38PH manufactured by Hermis Co., Ltd., the sheet is indirectly heated from both sides, and after the heater evacuates, the female mold is raised, The mold was lowered and a molded body was produced by a match mold molding method. The heater temperature on the lower surface was 270 ° C., the heater temperature on the upper surface was 230 ° C., and the sheet was molded after heating.

(Vacuum forming)
After the decorative laminated sheet is clamped using a FE38PH small vacuum forming machine manufactured by Hermis Co., Ltd., the sheet is indirectly heated from both sides, the heater is retracted, the female mold is raised, and the molded body is formed by the vacuum forming method. Was made. The heating time was 20 seconds, the sheet temperature was 160 ° C. ± 3 ° C., the heater temperature was 370 ° C., the sheet-heater distance was 130 mm, the mold temperature was 40 ± 3 ° C., and the vacuum / cooling time was 8 seconds.

(Insert molding)
The top surface of the surface layer (A) side of the molded body obtained by match mold molding was brought into close contact with the female mold of the injection mold and heated at a mold temperature of 40 ° C. and then heated to 200 ° C. A molten resin made of Novatec's PP resin (trade name “TX1868H5”) was injected into a mold and integrally molded, and an injection molded body for providing a decorative laminated sheet on the surface layer was prepared. The injection molding machine is Sumitomo Nestal Injection Molding Machine Promat 80/40 from Sumitomo Heavy Industries, Ltd., and the mold is 65mm x 40mm x 3mm and 1.5mm (thickness 3mm) And 1.5 mm two-stage stepped plate).
The sheet temperature at the time of insert molding was about 200 ° C., the same as that of the injection resin. The sheet temperature was measured at the time of injection molding by attaching a thermocouple thermometer between the mold surface and the sheet.

The gloss value was evaluated for the molded body obtained by the match molding method, and the maximum development rate was evaluated for the molded body obtained by the vacuum molding method. Physical properties such as scratch resistance, solvent resistance, acid resistance, and adhesiveness are insert molded products using the bottom part of the molded decorative laminated sheet with 150% and 250% expansion ratio obtained by the vacuum forming method. Created and evaluated about it.
The evaluation results are shown in Tables 1 and 2.

* 1 Hardener: BURNOCK DN-981 (trade name, manufactured by Dainippon Ink & Chemicals, Inc., isocyanurate ring-containing polyisocyanate, number average molecular weight 1000, non-volatile content 75% (solvent: ethyl acetate), isocyanate (NCO) functional The base concentration is 13.7%.
* 2 (1% dibutyltin dilaurate butyl acetate solution)
* 3 NCO / OH equivalent ratio: equivalent amount of isocyanate group in the curing agent and thermoplastic resin

* 1 Hardener: BURNOCK DN-981 (trade name, manufactured by Dainippon Ink & Chemicals, Inc., isocyanurate ring-containing polyisocyanate, number average molecular weight 1000, non-volatile content 75% (solvent: ethyl acetate), isocyanate (NCO) functional The base concentration is 13.7%.
* 2 (1% dibutyltin dilaurate butyl acetate solution)
* 3 NCO / OH equivalent ratio: Amount of isocyanate group of curing agent and equivalent ratio of thermoplastic resin * 4 Block isocyanate: Takenate B-815N (trade name, Takeda Pharmaceutical Company Limited, hydrogenated diphenylmethane diisocyanate ketoxime block body ), Isocyanate) (NCO) functional group concentration is 7.3%.

Comparative Example 1 is an example in which the isocyanate reaction rate was less than 20%, but the surface layer during molding was insufficiently cured, and the scratch resistance and gloss were reduced.
Comparative Example 2 is an example having no secondary hydroxyl group, but was inferior in scratch resistance. Comparative Examples 3 to 6 are examples in which there are no or few secondary hydroxyl groups and the acid value is too much, but all have a low maximum expansion rate and cracks have occurred.
In Comparative Example 7 using blocked isocyanate, the gloss value was lowered.

Claims (4)

A decorative laminated sheet in which a surface layer (A), a transparent or translucent thermoplastic resin layer (B), an ink layer (C), and a supporting base layer (D) are laminated in this order. The surface layer (A) contains a thermoplastic resin having a secondary hydroxyl group, an acid value of 1.0 (KOHmg / g) or less and a glass transition temperature of 30 to 100 ° C., and a polyisocyanate compound. And the laminated sheet for decoration characterized by being a layer semi-cured in the range of 20 to 80% of the isocyanate reaction rate. The thermoplastic resin of the surface layer (A) has an acid value of 1.0 (KOHmg / g) or less, a hydroxyl value of 30 to 120 (KOHmg / g), and a ratio of secondary hydroxyl groups in the hydroxyl group of 50 to 100. The laminated sheet for decorating according to claim 1, which is a vinyl copolymer having a mol% and a number average molecular weight of 5,000 to 50,000. The laminated sheet for decorating according to claim 1, wherein the ink layer (C) is a mirror-like metallic glossy ink layer containing metal thin film strips. A method for producing a coated molded article by supplying a molding resin to a mold after the laminated sheet for decorating according to claim 1 is brought into close contact with the mold surface. A method for producing a coated molded product, characterized in that the sheet temperature when the laminated sheets are brought into close contact is 100 ° C or higher.