JP2008173783A - Multilayer film for decoration - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multilayer film for decoration which is excellent in chemical resistance and transparency. <P>SOLUTION: In the multilayer film for decoration, an acrylic resin is used as a base material (1), and a resin composition (A+B=100 pts.wt.) comprising 5-95 wt.% of a (co)polymer (A) prepared from 100-70 wt.% of an aromatic vinyl monomer and 0-30 wt.% of an alkyl (meth)acrylate monomer and 95-5 wt.% of a polycarbonate resin (B) is laminated as a surface layer (2) on the surface of the base material. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a decorative multilayer film having good chemical resistance and transparency, and particularly to a decorative multilayer film that can be suitably used for vehicle interior use.

Thermoplastic resins such as ABS resin and polyolefin resin are used in various molded products, but secondary processing such as painting and plating may be performed depending on the application in order to improve design properties.
Since such processing generally uses a solvent and has a very high environmental impact, as a means to replace these, there is a case where a method of bonding a printed or metal-deposited film to the surface of a molded product is taken. It is increasing.
In such a case, it is common to use an acrylic resin film that is excellent in transparency and scratch resistance, but there are cases in which the trace remains when a specific solvent adheres to the surface. For example, a multilayer film having a polycarbonate resin as a surface layer has been studied.
However, existing multi-layer films are not satisfactory in terms of durability, moldability, transparency, and chemical resistance, and there is a need for immediate improvement. .
JP 2002-18894 A

  An object of the present invention is to provide a decorative multilayer film which has good transparency and chemical resistance, and can be suitably used particularly for vehicle interiors.

As a result of intensive studies in view of such problems, the present inventors have obtained the above object by laminating a specific polymer composed of a specific monomer composition and a composition composed of a polycarbonate resin on the surface of an acrylic resin. The present invention has been found out to achieve the above.
That is, the present invention uses an acrylic resin as a base material (1), and the surface thereof comprises 100 to 70% by weight of an aromatic vinyl monomer and 0 to 30% by weight of a (meth) acrylic acid alkyl ester monomer. A (co) polymer (A) 5 to 95 wt% and a polycarbonate resin (B) 95 to 5 wt% resin composition (A + B = 100 parts by weight) is laminated as a surface layer (2), A multilayer film for decoration is provided.

  The decorative multilayer film obtained in the present invention is excellent in transparency and chemical resistance, and can be used for decorative applications of various molded products. Especially for automotive interior parts that require high performance. It is very useful as a decorative film.

Hereinafter, the present invention will be described in detail.
The multilayer film for decoration in the present invention uses an acrylic resin as a base material (1), and has an aromatic vinyl monomer 100 to 70% by weight and a (meth) acrylic acid alkyl ester monomer 0 to 0 on its surface. A resin composition (A + B = 100 parts by weight) consisting of 30% by weight of a (co) polymer (A) 5 to 95% by weight and a polycarbonate resin (B) 95 to 5% by weight is laminated as a surface layer (2). It is obtained.

  As acrylic resin which comprises the base material (1) in this invention, the copolymer of a polymethacrylic acid alkylester, a methacrylic acid alkylester, and an acrylic acid alkylester etc. are mentioned, for example. Examples of the alkyl methacrylate include methyl methacrylate and ethyl methacrylate. The alkyl group in the alkyl acrylate ester is preferably an alkyl group having 2 to 10 carbon atoms. Examples of the alkyl acrylate ester include acrylate esters, propyl acrylate, isopropyl acrylate, n-butyl acrylate, Examples include isobutyl acrylate, hexyl acrylate, octyl acrylate, and the like. When a copolymer of alkyl methacrylate and alkyl acrylate is used as the acrylic resin, the alkyl methacrylate unit in the copolymer is 50% by weight or more, preferably 50 to 99% by weight, and the alkyl acrylate unit. Is not more than 50% by weight, preferably 50 to 1% by weight. In addition, the acrylic resin may further contain other monomer units and / or rubber components as copolymerization components as long as the object of the present invention is not impaired.

Examples of the aromatic vinyl monomer constituting the (co) polymer (A) of the surface layer (2) in the present invention include styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, and p-methylstyrene. , Α-methyl-p-methylstyrene, halogenated styrene, ethyl styrene, p-isopropyl styrene, pt-butyl styrene, 2,4-dimethyl styrene, divinyl benzene, etc. As the polymer, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl acrylate, phenyl (meth) acrylate, 4-t-butylphenyl (meth) acrylate , Bromophenyl (meth) acrylate, dibromophenyl (meth) Examples include acrylate, 2,4,6-tribromophenyl (meth) acrylate, monochlorophenyl (meth) acrylate, dichlorophenyl (meth) acrylate, trichlorophenyl (meth) acrylate, and the like. It is possible to select and use. Among these, in particular, styrene is used as an aromatic vinyl monomer, and methyl acrylate, butyl acrylate, methyl methacrylate, butyl methacrylate, and phenyl (meth) acrylate are used as (meth) acrylic acid ester monomers. preferable.
In the present invention, monomers that can be copolymerized with these monomers within a range that does not impede its purpose, for example, vinyl cyanide monomers such as acrylonitrile, methacrylonitrile, ethacrylonitrile, fumaronitrile, 1 type of maleimide monomers such as N-phenylmaleimide and N-cyclohexylmaleimide, unsaturated carboxylic acids such as acrylic acid, methacrylic acid and (anhydrous) maleic acid, and epoxy group-containing monomers such as glycidyl methacrylate Alternatively, two or more types can be selected and used.

  It is important that the aromatic vinyl monomer in the (co) polymer (A) in the present invention is 100 to 70% by weight. When this content is less than 70% by weight (the (meth) acrylic acid alkyl ester monomer exceeds 30% by weight), when mixed with the polycarbonate resin (B), the transparency characteristic of the present invention is impaired. In addition, the transparency when laminated with the substrate (1) is also unfavorable. Preferably, it is 99 to 70% by weight of an aromatic vinyl monomer and 1 to 30% by weight of a (meth) acrylic acid alkyl ester monomer.

  The (co) polymer (A) in the present invention can be produced by a known polymerization method. Among them, the bulk polymerization method or the solution polymerization method is preferable, and the continuous block or solution polymerization method is more preferable. Used. More specifically, a raw material in which a (meth) acrylic acid ester monomer, an aromatic vinyl monomer, and, if necessary, a solvent such as ethylbenzene, toluene, methyl ethyl ketone, etc., is supplied to the polymerization step, After the step of polymerizing the monomer and after the step, the mixed liquid containing the polymer, the unreacted monomer and / or the solvent is heated, and simultaneously or after heating, the mixture is introduced into the decompression chamber and the unreacted monomer and / or Or the separation and recovery process for separating the solvent from the polymer, and further pelletizing the polymer discharged from the recovery process by adding additives such as colorants, antioxidants, and diffusing agents as necessary. It is preferable to consist of the granulation process.

  The pH of the (co) polymer (A) in the present invention is preferably 7.0 or less from the viewpoint of product durability. More preferably, it is 6.0 or less. In addition, this pH is determined by adding an acid component such as phosphoric acid when the copolymer is mixed with the polymerization method, the polymerization additive and the amount thereof, or the (co) polymer (A) and the polycarbonate. It is possible to adjust arbitrarily.

  Furthermore, the alkali metal salt in the (co) polymer (A) in the present invention is preferably less than 0.1% by weight in terms of the durability of the product, like the pH. In addition, about content of an alkali metal salt, it is arbitrary by the polymerization method of (co) polymer (A), the additive at the time of superposition | polymerization, adjustment of the quantity, or the washing | cleaning method of (co) polymer (A). It is possible to adjust.

  The polycarbonate resin (B) constituting the surface layer (2) in the present invention is a phosgene method in which various dihydroxydiaryl compounds and phosgene are reacted, or a transesterification method in which a dihydroxydiaryl compound and a carbonate such as diphenyl carbonate are reacted. Typical examples include 2,2-bis (4-hydroxyphenyl) propane; polycarbonate resin produced from “bisphenol A”.

  Examples of the dihydroxydiaryl compound include bisphenol A, bis (4-hydroxydiphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 2,2-bis (4-hydroxyphenyl) butane, 2, 2-bis (4-hydroxyphenyl) octane, bisbis (4-hydroxydiphenyl) phenylmethane, 2,2-bis (4-hydroxydiphenyl-3-methylphenyl) propane, 1,1-bis (4-hydroxy-3) -Tert-butylphenyl) propane, 2,2-bis (4-hydroxy-3-bromophenyl) propane, 2,2-bis (4-hydroxy-3,5dibromophenyl) propane, 2,2-bis (4 Bis (hydroxyaryl) alkanes such as -hydroxy-3,5-dichlorophenyl) propane; , 1-bis (4-hydroxyphenyl) cyclopentane, bis (hydroxyaryl) cycloalkanes such as 1,1-bis (4-hydroxyphenyl) cyclohexane, 4,4′-dihydroxydiphenyl ether, 4,4′- Dihydroxy diaryl ethers such as dihydroxy-3,3′-dimethyldiphenyl ether, 4,4′-dihydroxydiphenyl sulfide, dihydroxydiaryl sulfides such as 4,4′-dihydroxy-3,3′-dimethyldiphenyl sulfide Dihydroxy diaryl sulfoxides such as 4,4′-dihydroxydiphenyl sulfoxide, dihydro such as 4,4′-dihydroxydiphenyl sulfone, 4,4′-dihydroxy-3,3′-dimethyldiphenyl sulfone Siji aryl sulfones and the like.

  These may be used alone or in combination of two or more. In addition to these, piperazine, dipiperidyl hydroquinone, resorcin, 4,4′-dihydroxydiphenyls, and the like may be mixed.

  Further, the above-mentioned dihydroxydiaryl compound and a trivalent or higher valent phenol compound as shown below may be mixed and used. Trihydric or higher phenols include phloroglucin, 4,6-dimethyl-2,4,6-tri- (4-hydroxyphenyl) -heptene-2,4,6-dimethyl-2,4,6-tri- (4 -Hydroxyphenyl) -heptane, 1,3,5-tri- (4-hydroxyphenyl) -benzol, 1,1,1-tri- (4-hydroxyphenyl) -ethane and 2,2-bis- (4 4 '-(4,4'-hydroxydiphenyl) cyclohexyl) -propane and the like. In addition, when manufacturing these polycarbonate resins, a molecular weight regulator, a catalyst, etc. can be used as needed.

  The surface layer (2) in the present invention comprises 5 to 95% by weight of the above (co) polymer (A) and 95 to 5% by weight of the polycarbonate resin (B), and the (co) polymer (A) is If it is less than 5% by weight (polycarbonate resin (B) exceeds 95% by weight), it tends to be inferior in multilayer film formability and subsequent vacuum formability, and if (co) polymer (A) exceeds 95% by weight (Polycarbonate resin (B) is less than 5% by weight) This is not preferred because the strength tends to be insufficient.

  In the present invention, it is desirable from the viewpoint of light resistance to contain 0.01 to 5 parts by weight of a hindered amine light stabilizer and / or an ultraviolet absorber with respect to 100 parts by weight of the resin composition of the surface layer (2). Examples of such hindered amine light stabilizers and / or ultraviolet absorbers include commercially available hindered amine light stabilizers (for example, ADK STAB LA-77, LA-52, LA-57, LA-62 manufactured by Asahi Denka Kogyo Co., Ltd., LA-67, LA-63P, LA-68LD (trade name) and the like, and commercially available benzotriazole ultraviolet absorbers (Tinvin P, 234, 326, 329, 360 (trade name), etc. manufactured by Ciba Specialty Chemicals), Examples include commercially available benzophenone-based ultraviolet absorbers (Sumitomo Chemical Co., Ltd., Sumisorb 100, 110, 130 (trade name), etc.) and commercially available benzoate ultraviolet absorbers (Sumitomo Chemical Co., Ltd., Sumisorb 400 (trade name), etc.). One type or two or more types can be selected and used.

  The multilayer film for decoration in the present invention is one in which the surface layer (2) is laminated on the surface of the acrylic resin substrate (1), and the thickness of the substrate (1) and the surface layer (2). Although there is no restriction | limiting in particular, Preferably it is base material (1) 0.05-0.5 mm and surface layer (2) 0.005-0.1 mm.

Further, in the acrylic resin substrate (1) and / or the surface layer (2) constituting the decorative multilayer film of the present invention, as a diffusing agent, for example, inorganic materials such as titanium oxide, silica, barium sulfate, calcium carbonate and the like. Organic crosslinked fine particles made of fine particles, methacrylic resin, silicon resin or the like can be used. Although there is no restriction | limiting in particular about the average particle diameter of these diffusing agents, It is preferable that it is the range of 0.1-20 micrometers.
Moreover, it is also possible to add a dye / pigment, a lubricant, a mold release agent, an antioxidant and the like as long as the characteristics are not impaired.
In addition, it is preferable that the shaping | molding temperature at the time of shape | molding the multilayer film for decorating of this invention is 200-280 degreeC.

Further, the method for forming the decorative multilayer film of the present invention is not particularly limited. For example, molding using a multilayer extruder such as a multilayer sheet extruder or a multilayer inflation molding machine, or individual roll molding, calendar molding, sheet Each film formed by molding or inflation molding can be molded by bonding with an adhesive or a hot press method.
The decorative multilayer film thus produced is applied to the surface of a thermoplastic resin such as an ABS resin or a polyolefin resin by using an insert molding method or an in-mold molding method using an injection molding machine or a press molding machine. It is possible to combine.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further more concretely, this invention is not restrict | limited at all by these.

〔Example〕
-Base material (1)-
Base material (1): Acrylic resin (SUMIPEX HT55Y: manufactured by Sumitomo Chemical Co., Ltd.)

-Surface material (2)-
The (co) polymer (A) used for the surface layer was prepared by the following method.
<Production of (co) polymer (A)>
Copolymer A-1: Copolymer A-1 was produced using a continuous polymerization apparatus consisting of one fully mixed reaction tank having a capacity of 20 liters. 92 parts by weight of styrene, 8 parts by weight of methyl methacrylate, 0.05 parts by weight of t-dodecyl mercaptan, 0.015 parts by weight of t-butylperoxy (2-ethylhexanoate) as a polymerization initiator, 10 parts by weight of ethylbenzene The polymerization raw material consisting of the above was continuously fed to the reaction vessel at a rate of 13 kg / h using a plunger pump to carry out the polymerization, the polymerization temperature was adjusted, and the polymerization conversion rate at the reaction vessel outlet was adjusted to 53.5% by weight. . The polymerization temperature at this time was 150 ° C. The number of revolutions in the reaction vessel was 150 rpm, and the polymerization temperature was measured by inserting thermocouples in the upper, middle, and lower portions of the reaction vessel. The temperature at the three locations was an average value of ± 0.2 ° C. It is considered that the polymerization liquid is uniformly mixed. Following the polymerization, the polymerization solution continuously drawn out from the reaction vessel is supplied to a devolatilizer to separate volatile components such as unreacted monomers and organic solvents, and then the resin is passed through an extruder. Pelletization was performed to prepare a copolymer A-1.
Polystyrene-converted average weight molecular weight Mw and molecular weight distribution Mw / Mn were measured using high-performance liquid chromatography (manufactured by Shimadzu Corporation) and Shimadzu HSG column in 0.02 g of the obtained copolymer dissolved in 10 ml of THF (hereinafter the same) When measured by a method), they were 180,000 and 2.1, respectively. Further, the polymer was incinerated, dissolved in pure water, and quantified by ICP method and atomic absorption method (hereinafter measured by the same method). The content of alkali metal salt was 0.003% by weight, 1 g of the combined product was dissolved in 40 ml of acetone, then 40 ml of methanol and 40 ml of pure water were added, and the pH of the supernatant obtained by allowing to stand for 1 hour was measured (hereinafter measured by the same method) and found to be 6.3. .

  Copolymer A-2: Copolymer A-2 was prepared in the same manner as Copolymer A-1, except that 5 parts by weight of methyl methacrylate, 95 parts by weight of styrene, and 0.1 parts by weight of t-dodecyl mercaptan were used. Created. The copolymer A-2 had a Mw of 120,000, a Mw / Mn of 2.2, an alkali metal salt content of 0.002% by weight, and a pH of 6.4.

  Copolymer A-3: A copolymer A-3 was prepared in the same manner as the copolymer A-1, except that 100 parts by weight of styrene and 0.2 parts by weight of t-dodecyl mercaptan were used. The copolymer A-3 had a Mw of 90,000, a Mw / Mn of 2.1, an alkali metal salt content of 0.002% by weight, and a pH of 6.4.

  Copolymer A-4: Copolymer A-4 was prepared in the same manner as Copolymer A-1, except that 20 parts by weight of phenyl methacrylate, 80 parts by weight of styrene, and 0.2 parts by weight of t-dodecyl mercaptan were used. Created. The copolymer A-4 had a Mw of 100,000, Mw / Mn of 2.2, an alkali metal salt content of 0.002% by weight, and a pH of 6.4.

  Copolymer A-5: Copolymer A-5 was prepared in the same manner as Copolymer A-1, except that 20 parts by weight of methyl methacrylate, 80 parts by weight of styrene, and 0.01 parts by weight of t-dodecyl mercaptan were used. Created. Copolymer A-5 had Mw of 190,000, Mw / Mn of 2.2, alkali metal salt content of 0.002% by weight, and pH of 6.4.

  Copolymer A-6: Nitrogen-substituted glass reactor was charged with 110 parts of pure water and heated to 70 ° C. Thereafter, an emulsifier aqueous solution in which 1.0 part of potassium oleate was dissolved in 5 parts by weight of methyl methacrylate, 95 parts by weight of styrene and 0.2 part by weight of t-dodecyl mercaptan and 20 parts of pure water was added for 4 hours. Over a period of time. Thereafter, the polymerization was continued for 3 hours to complete the polymerization. After the completion of polymerization, 5 parts of 10% aqueous sodium hydroxide solution was added per 100 parts by weight of copolymer latex (solid content), and then salted out, dehydrated and dried using magnesium sulfate to obtain copolymer A-6. It was. Copolymer A-6 had Mw of 100,000, Mw / Mn of 2.5, alkali metal salt content of 0.85% by weight, and pH of 8.9.

  Copolymer Ai: Copolymer A-7 was obtained in the same manner as Copolymer A-6, except that 20 parts by weight of acrylonitrile, 80 parts by weight of styrene, and 0.2 parts by weight of t-dodecyl mercaptan were used. . Copolymer A-7 had Mw of 90,000, Mw / Mn of 2.8, alkali metal salt content of 0.91% by weight, and pH of 8.2.

  Copolymer A-ii: Copolymer A-ii was prepared in the same manner as copolymer A-1, except that 40 parts by weight of methyl methacrylate, 60 parts by weight of styrene, and 0.01 parts by weight of t-dodecyl mercaptan were used. Created. The copolymer A-ii had a Mw of 190,000, a Mw / Mn of 2.2, an alkali metal salt content of 0.002% by weight, and a pH of 6.4.

-Polycarbonate resin (B)-
B-1: Caliber 200-20 (manufactured by Sumitomo Dow)

Surface layer (2): A twin-screw extruder (Japan) in which the copolymers A-1 to 6 and Ai to ii and the polycarbonate resin B-1 were mixed at a ratio shown in Table 1 and the cylinder temperature was set to 220 ° C. It was melt-kneaded with TEM-35 manufactured by Steel Works, and pellets of the resin composition (1-12) for the surface layer (2) shown in Table 1 were obtained.

[Examples 1-8, Comparative Examples 1-5]
Preparation of test piece: Using base material (1) “acrylic resin” and resin composition (1-12) for surface layer (2) shown in Table 2, each cylinder temperature was changed to base material (1): 230 ° C. Surface layer (2): Set to 240 ° C., and using a 65 mm multilayer extruder, a two-layer film having a substrate thickness of 0.1 mm and a surface layer thickness of 0.03 mm was prepared.

Transparency : The haze of the prepared film was measured using a haze meter (HM-150 Murakami Color Research Laboratory).
Chemical resistance : A 10% lactic acid aqueous solution was dropped on the prepared film, left in a hot air circulation oven at 80 ° C. for 12 hours, the lactic acid aqueous solution was wiped off, and the surface state of the film was visually observed.
○: No change ×: Drop marks are observed
Adhesiveness : A cross-cut test was performed according to JIS K5400, and the following evaluation was made based on the number of peeled squares. ○: Less than 5 peeled squares X: 5 or more peeled squares
Durability : Specimen type 5 described in JIS K7127 was punched out from the prepared film and left in a constant temperature and humidity chamber having a temperature of 85 ° C. and a relative humidity of 90% for 1000 hours. Thereafter, a tensile test was performed at a test speed of 50 mm / min in accordance with JIS K7161, and the elongation retention was determined from the following formula.
Retention rate = tensile elongation after standing / tensile elongation before standing × 100 (%)

  Since the multilayer film in the present invention is excellent in chemical resistance and transparency, it can be used effectively as a decorative film for various molded products, and can be used very beneficially as a decorative film for vehicle interior.

Claims (4)

A (co) polymer comprising an acrylic resin as a base material (1) and comprising 100 to 70% by weight of an aromatic vinyl monomer and 0 to 30% by weight of a (meth) acrylic acid alkyl ester monomer on the surface thereof. (A) 5 to 95% by weight and polycarbonate resin (B) A resin composition (A + B = 100 parts by weight) composed of 95 to 5% by weight is laminated as a surface layer (2). the film. The pH of the (co) polymer (A) constituting the surface layer (2) is less than 7, and the content of the alkali metal salt in the copolymer (A) is less than 0.1% by weight. The multilayer film for decorating of description. Copolymer comprising (co) polymer (A) constituting surface layer (2) comprising 99 to 70% by weight of aromatic vinyl monomer and 1 to 30% by weight of (meth) acrylic acid alkyl ester monomer The multi-layer film for decoration according to claim 1 or 2, wherein the multi-layer film for decoration is a combined body. The multilayer film for decoration according to any one of claims 1 to 3, wherein the multilayer film is used for vehicle interior.