JP2010037429A - Film for use in automobile - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an acrylic film for use in automobiles which is excellent in the chemical resistance and the surface hardness. <P>SOLUTION: The acrylic film for use in automobiles, being formed by molding an acrylic resin composition containing 100 parts by weight of an acrylic-based resin composition (E) and 1-15 parts by weight of a plasticizer having an acid value of 0.3-5.5 mmol/g, a weight-average molecular weight of 3,000-30,000 and a glass transition temperature of 40-115°C, is characterized in that the acrylic-based resin composition (E) includes an acrylic-based resin (C) obtained by polymerizing a monomer mixture (A) containing 50-100% by weight of an alkyl methacrylate and 0-50% by weight of an alkyl acrylate in the presence of acrylate-based crosslinked elastomer particles (B), thereby providing the excellent resistance to chemicals (especially, resistance to a suntan preventive agent) and the excellent surface hardness. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an acrylic resin film suitable for an automobile film.

  In recent years, there has been an increasing demand for high design in applications where resin films are introduced to the outermost exterior of automobile interior and exterior parts for the purpose of protecting and decorating the base material, and acrylic films with excellent transparency have attracted attention. Yes. However, the conventional acrylic film has insufficient chemical resistance, heat resistance and bending resistance, and whitening resistance required for this application. Moreover, in the film obtained from the conventional acrylic resin, the surface hardness of the film was insufficient, and there was a tendency to be easily damaged.

  Therefore, as a resin imparted with these characteristics, polyglutarimide obtained by treating an acrylic resin with an imidizing agent and introducing an imide group into a polymer chain is known, and has chemical resistance and heat resistance. Excellent in heat resistance, heat stability and hardness. In particular, as having excellent heat resistance and chemical resistance, methacrylic acid or methacrylic acid tert-butyl ester, or both are copolymerized with methyl methacrylate and heat-treated to form an acid anhydride unit, An imidized acrylic resin that has been reacted with an imidizing agent to improve heat resistance, transparency, and solvent resistance is disclosed (see Patent Document 1).

  However, since the resin is very brittle, when the resin is made into a film and laminated on a base material, it has a drawback that it is inferior in the bending resistance required as processing characteristics.

  Therefore, as a countermeasure to these disadvantages, the polymer is composed of methacrylic ester-based polymerized and acrylate-based cross-linked elastic particles having a specific composition, and the cross-linked elastic particle (B) has an average particle size and a polyfunctional monomer. Excellent chemical resistance, heat resistance, thermal stability and hardness obtained by treating a methacrylic resin composition that satisfies the specific relational expression with a body with an imidizing agent, and has excellent bending resistance and whitening resistance. An improved imidized acrylic resin is disclosed (see Patent Document 2). The imidized acrylic resin is excellent in chemical resistance, but in recent automobile member applications, chemical resistance that can also be applied to sunscreen chemicals [for example, Copatone (registered trademark)] has been required. Further improvement in chemical resistance to such special drugs has been desired.

  On the other hand, a rubber-containing acrylic having improved heat resistance, solvent resistance, and optical isotropy by forming a glutaric anhydride group by heat-treating a resin previously copolymerized with 15 to 50% by weight of an unsaturated carboxylic acid. Resin is disclosed (refer patent document 3). However, when the resin contains a large number of acid anhydride groups as in the case of the resin, it is excellent in resistance to an organic solvent, but has a disadvantage that resistance to an alkaline aqueous solution is deteriorated.

Accordingly, there is no acrylic film for automobiles having various physical properties such as a balance of various chemical resistances, bendability and hardness, and development has been desired.
JP-A 62-4704 JP-A-2005-290136 JP 2004-292812 A

  An object of the present invention is to provide an automotive acrylic film which has excellent chemical resistance against various chemicals and resistance to bending whitening and has improved surface hardness.

  As a result of intensive studies, the present inventors have found that an acrylic film obtained from an acrylic resin composition containing a specific amount of a plasticizer having a specific acid value and molecular weight has sunscreen resistance, alkali resistance, and xylene resistance. It has been found that it is possible to produce an automotive film having excellent thermal stability and resistance to bending whitening, and the present invention has been completed.

That is, the present invention
1 plasticizer having an acid value of 0.3 to 5.5 mmol / g, a weight average molecular weight of 3000 to 30000, and a glass transition temperature of 40 to 115 ° C. with respect to 100 parts by weight of the acrylic resin composition (E). A film for an automobile formed by molding an acrylic resin composition containing -15 parts by weight,
Acrylic resin composition (E)
Two or more non-conjugated double bonds per molecule per 100 parts by weight of a monomer mixture containing 50 to 100% by weight of an acrylic acid alkyl ester monomer and 0 to 50% by weight of a methacrylic acid alkyl ester monomer In the presence of acrylic ester-based crosslinked elastic particles (B) obtained by mixing and polymerizing 0.5 to 5 parts by weight of a polyfunctional monomer having
For automobiles comprising an acrylic resin (C) obtained by polymerizing a monomer mixture (A) containing 50 to 100% by weight of an alkyl methacrylate and 0 to 50% by weight of an acrylic acid alkyl ester The present invention relates to an acrylic film (claim 1).

Furthermore, the acrylic resin composition (E)
Furthermore, it is related with the acrylic film for motor vehicles (Claim 2) of Claim 1 containing the thermoplastic resin (D) whose acid value is less than 0.7 mmol / g.

  Further, the acrylic resin composition (E) comprises 50 to 99% by weight of the acrylic resin (C) and 0 to 50% by weight of the thermoplastic resin (D) [the total of (C) and (D) is 100% by weight. ] The acrylic film for automobiles according to any one of claims 1 and 2 (claim 3).

  Furthermore, it is related with the acrylic film for motor vehicles (Claim 4) in any one of Claims 1-3 whose acid value of an acrylic resin composition is 0.2-0.7 mmol / g.

  Furthermore, it is related with the acrylic film for motor vehicle interiors in any one of Claims 1-4 (Claim 5).

  Furthermore, it is related with the acrylic film for motor vehicle exterior in any one of Claims 1-4 (Claim 6).

  Furthermore, it is related with the laminated article (Claim 7) obtained by laminating | stacking the acrylic film for motor vehicles in any one of Claims 1-4.

  Furthermore, the present invention relates to a vehicle interior part (claim 8) obtained by laminating the automotive interior acrylic film according to claim 5.

  Furthermore, the present invention relates to an automotive exterior part (Claim 9) obtained by laminating the automotive exterior acrylic film according to Claim 6.

  ADVANTAGE OF THE INVENTION According to this invention, it is possible to provide the acrylic film for motor vehicles which was excellent in chemical resistance and bending whitening resistance, and was improved in surface hardness.

  In the present invention, the “acrylic resin (E)” means an acrylic resin (C) or a blend resin of the acrylic resin (C) and the thermoplastic resin (D).

  In the acrylic resin composition of this invention, the chemical resistance of the film obtained can be improved by containing a specific plasticizer with respect to an acrylic resin composition (E).

  The plasticizer used in the present invention preferably contains a carboxyl group such as (meth) acrylic acid or its anhydride. The other comonomer unit contained in the plasticizer is not particularly limited as long as it is an ethylenically unsaturated monomer unit copolymerizable with the (meth) acrylic acid monomer. Examples of the copolymerizable ethylenically unsaturated monomer include aromatic vinyl such as styrene and α-methylstyrene; vinyl halide such as vinyl chloride and vinyl bromide; vinyl cyanide such as acrylonitrile and methacrylonitrile. Vinyl esters such as vinyl toluene, vinyl naphthalene, vinyl formate, vinyl acetate and vinyl propionate; vinylidene halides such as vinylidene chloride and vinylidene fluoride; acrylates such as sodium acrylate and calcium acrylate; β-acrylate Acrylic acid alkyl ester derivatives such as hydroxyethyl, dimethylaminoethyl acrylate, glycidyl acrylate, acrylamide, and N-methylol acrylamide; methacrylates such as sodium methacrylate and calcium methacrylate, methacrylamide, methacrylate And methacrylic acid alkyl ester derivatives such as β-hydroxyethyl laurate, dimethylaminoethyl methacrylate, and glycidyl methacrylate. These monomers may be used alone or in combination of two or more.

The acid value of the plasticizer used in the present invention is preferably 0.3 to 5.5 mmol / g, and more preferably 2.0 to 4.5 mmol / g. If the acid value of the plasticizer is less than 0.3 mmol / g, chemical resistance of the resulting acrylic resin composition may be insufficient, and if the acid value exceeds 5.5 mmol / g, the resulting film has poor transparency. There is a case.
The acid value in the present invention is a value measured by adding a predetermined amount of an aqueous sodium hydroxide solution to a resin dissolved in a solvent and neutralizing the solution with an aqueous hydrochloric acid solution.

  The weight average molecular weight of the plasticizer used in the present invention is preferably in the range of 3000 to 30000, and more preferably in the range of 5000 to 20000. When the weight average molecular weight of the plasticizer is less than 3000, when forming a film or the like by the T-die extrusion method, there is a tendency that the eyes will not easily adhere to the T die lip, and when the weight average molecular weight exceeds 30000, the resulting acrylic resin The fluidity of the composition tends to be low, and the die line tends to stand out in the resulting film.

The glass transition temperature of the plasticizer used in the present invention is preferably in the range of 40 to 115 ° C, more preferably in the range of 60 to 110 ° C. When the glass transition temperature of the plasticizer is less than 40 ° C., the resulting acrylic resin composition may have insufficient heat resistance, and the resulting film may have poor transparency.
In addition, the glass transition temperature in this invention is the value measured by measuring in a nitrogen atmosphere using a differential scanning calorimeter [DSC, the Shimadzu Corporation make, DSC-50 type | mold].

  The plasticizer content in the acrylic resin composition of the present invention is preferably 1 to 15 parts by weight and preferably 3 to 10 parts by weight with respect to 100 parts by weight of the acrylic resin composition (E). More preferred. If the content of the plasticizer is less than 1 part by weight, the resulting acrylic resin composition tends to have insufficient chemical resistance. If it exceeds 15 parts by weight, the alkali resistance of the resulting film is deteriorated or the transparency is poor. There is a case.

  The acrylic resin composition (E) in the acrylic resin composition of the present invention may be only the acrylic resin (C) alone, but from the viewpoint of fluidity, the acrylic resin (C) and the thermoplastic resin (D). And a mixed resin.

  The acrylic resin (C) in the present invention is a resin obtained by polymerizing the (meth) acrylic acid alkyl ester monomer mixture (A) in the presence of the acrylic ester-based crosslinked elastic particles (B). Is preferable from the viewpoint of transparency and strength of the film.

  The acrylic ester-based crosslinked elastic particles (B) of the present invention are 100 parts by weight of a monomer mixture containing 50 to 100% by weight of an acrylic acid alkyl ester monomer and 0 to 50% by weight of a methacrylic acid alkyl ester monomer. In contrast, 0.5 to 5 parts by weight of a polyfunctional monomer having two or more non-conjugated double bonds per molecule is copolymerized in one or more stages (in a multistage, It is also possible to adjust the monomer composition or the reaction conditions.) A more preferable composition of the monomer mixture includes 60 to 100% by weight of an acrylic acid alkyl ester monomer and 0 to 40% by weight of a methacrylic acid alkyl ester monomer. When the methacrylic acid alkyl ester monomer is 50% by weight or less, it is preferable from the viewpoint of the bending resistance of the molded article and film that can be formed from the acrylic resin composition obtained.

  As a reactive monomer such as an alkyl acrylate ester or an alkyl methacrylate ester of the monomer mixture used for the crosslinked elastic particles (B), the alkyl group has 1 carbon atom from the viewpoint of polymerization reactivity and cost. Those of ˜12 are preferred. Specific examples thereof include methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, methyl acrylate, n-butyl acrylate and the like, and these monomers may be used alone. Well, two or more types may be used in combination.

  In addition, the monomer mixture of the crosslinked elastic particles (B) of the present invention may contain an ethylenically unsaturated monomer copolymerizable with an acrylic acid alkyl ester monomer or a methacrylic acid ester monomer, if necessary. A monomer or the like may be copolymerized. Examples of copolymerizable ethylenically unsaturated monomers include vinyl halides such as vinyl chloride and vinyl bromide, vinyl cyanides such as acrylonitrile and methacrylonitrile, vinyl toluene, vinyl naphthalene, styrene, and α-methyl. Aromatic vinyl such as styrene, vinyl esters such as vinyl formate, vinyl acetate and vinyl propionate, vinylidene halides such as vinylidene chloride and vinylidene fluoride, acrylic acid such as acrylic acid, sodium acrylate and calcium acrylate, and salts thereof , Β-hydroxyethyl acrylate, dimethylaminoethyl acrylate, glycidyl acrylate, acrylamide, N-methylol acrylamide, and other alkyl acrylate derivatives, methacrylic acid, sodium methacrylate, calcium methacrylate, etc. Examples thereof include tacrylic acid and salts thereof, methacrylic acid alkyl ester derivatives such as methacrylamide, β-hydroxyethyl methacrylate, dimethylaminoethyl methacrylate and glycidyl methacrylate. These monomers may be used alone or in combination of two or more.

  The acrylic ester-based crosslinked elastic particles (B) of the present invention are usually obtained because a polyfunctional monomer having two or more non-conjugated reactive double bonds per molecule is copolymerized. The resulting polymer exhibits crosslinking elasticity. In addition, one reactive functional group (double bond) of the polyfunctional monomer left unreacted during the polymerization of the acrylic ester-based crosslinked elastic particles (B) becomes a graft crossing point, It is considered that a part of the acrylic acid alkyl ester monomer mixture (A) is grafted to the acrylic ester-based crosslinked elastic particles (B).

  Examples of the polyfunctional monomer used in the present invention include allyl methacrylate, allyl acrylate, triallyl cyanurate, triallyl isocyanurate, diallyl phthalate, diallyl malate, divinyl adipate, divinylbenzene ethylene glycol dimethacrylate, divinyl. Benzene ethylene glycol diacrylate, diethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol dimethacrylate, triethylene glycol diacrylate, trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, tetramethylolmethane tetramethacrylate, tetramethylolmethane tetraacrylate, Dipropylene glycol dimethacrylate And dipropylene glycol acrylate, and the like. These polyfunctional monomers may be used alone or in combination of two or more.

  The copolymerization amount of the polyfunctional monomer in the acrylate-based crosslinked elastic particle (B) of the present invention is preferably 0.5 to 5 parts by weight with respect to 100 parts by weight of the monomer mixture. 0 to 4 parts by weight is more preferable. If the copolymerization amount of a polyfunctional monomer is 0.5-5 weight part, it is preferable from a viewpoint of bending resistance, bending whitening resistance, and the fluidity | liquidity of resin.

  The average particle diameter of the acrylate ester-based crosslinked elastic particles (B) of the present invention is preferably 500 to 2000, more preferably 500 to 1600, even more preferably 500 to 1200, and particularly preferably 600 to 1200. An average particle size of 500 to 2000 mm is preferred from the viewpoint of bending resistance, bending whitening resistance and transparency.

  The acrylic resin (C) used in the present invention is obtained by polymerizing a monomer mixture (A) containing a methacrylic acid alkyl ester as a main component in the presence of the acrylic ester-based crosslinked elastic particles (B). Is obtained. Preferably, 95 to 25 parts by weight of the (meth) acrylic acid alkyl ester monomer mixture (A) described later is at least one stage in the presence of 5 to 75 parts by weight of the acrylic ester-based crosslinked elastic particles (B). This is obtained by polymerization.

  The composition of the monomer mixture (A) in the acrylic resin (C) of the present invention is preferably 50 to 100% by weight of methacrylic acid alkyl ester and 0 to 50% by weight of acrylic acid alkyl ester, and 60 to 100 methacrylic acid alkyl ester. More preferred are wt% and acrylic acid alkyl ester 0-40 wt%. When the alkyl ester of acrylic acid exceeds 50% by weight, the heat resistance and hardness of the film that can be formed from the resulting methacrylic resin composition tend to be lowered. Moreover, you may copolymerize the ethylenically unsaturated monomer etc. which can be copolymerized with the (meth) acrylic-acid alkylester as needed. As specific examples of the copolymerizable ethylenically unsaturated monomer, those used in the crosslinked elastic particles (B) can be used.

  In this case, in the monomer mixture (A), a component (free polymer) that becomes an ungrafted polymer is generated without grafting to the acrylate-based crosslinked elastic particle (B).

  Part of the acrylic resin (C) [(B) and grafted (A)] becomes insoluble in methyl ethyl ketone.

  The graft ratio of the acrylic resin (C) in the present invention is preferably from 100 to 160%, more preferably from 120 to 140%. If the graft ratio is in the above range, the obtained (meth) acrylic resin film is preferable from the viewpoint of colorless transparency and bending whitening.

The graft ratio of the acrylic resin (C) of the present invention is calculated by the following method.
That is, 1 g of acrylic resin (C) was dissolved in 40 ml of methyl ethyl ketone, centrifuged using a centrifuge (manufactured by Hitachi Koki Co., Ltd., CP60E) at 3000 rpm for 1 hour, and decanted to give methyl ethyl ketone. Separated into insoluble and soluble components. The obtained methyl ethyl ketone insoluble matter was calculated as the acrylate ester-based crosslinked elastic body-containing graft copolymer by the following formula.
Graft ratio (%) = {(weight of insoluble matter of methyl ethyl ketone−weight of acrylic ester-based crosslinked elastic particle (B)) / weight of acrylic ester-based crosslinked elastic particle (B)} × 100

  The production method of the acrylic resin (C) of the present invention is not particularly limited, and a known emulsion polymerization method, emulsion-suspension polymerization method, suspension polymerization method and the like can be applied, but the emulsion polymerization method is particularly preferable.

  As an initiator in polymerization of acrylic ester-based crosslinked elastic particles (B) and polymerization of (meth) acrylic acid alkyl ester monomer mixture (A), known organic peroxides and inorganic peroxides are used. Initiators such as azo compounds can be used. Specifically, tertiary butyl hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, succinic acid peroxide, peroxymaleic acid tertiary butyl ester, cumene hydroperoxide, benzoyl peroxide, etc. Organic peroxides, inorganic peroxides such as potassium persulfate and sodium persulfate, and oil-soluble initiators such as azobisisobutyronitrile are also used. These may be used alone or in combination of two or more. These initiators combined with reducing agents such as sodium sulfite, sodium thiosulfate, sodium formaldehyde sulfoxylate, ascorbic acid, hydroxyacetone acid, ferrous sulfate, ferrous sulfate and disodium ethylenediaminetetraacetate It may also be used as a normal redox type initiator.

  The organic peroxide can be added by a known addition method such as a method of adding to a polymerization system as it is, a method of adding a mixture to a monomer, a method of adding a dispersion in an aqueous emulsifier solution, and the like. From the viewpoint of transparency, a method of adding a mixture to a monomer or a method of adding it by dispersing in an aqueous emulsifier solution is preferable.

  The organic peroxide is an organic reducing agent such as a divalent iron salt and / or organic solvents such as formaldehyde sulfoxylate, reducing sugar, ascorbic acid and the like from the viewpoint of polymerization stability and particle size control. It is preferably used as a redox initiator in combination with a reducing agent.

  The surfactant used for the emulsion polymerization is not particularly limited, and any surfactant for normal emulsion polymerization can be used. Specifically, for example, anionic surfactants such as sodium alkylsulfonate, sodium alkylbenzenesulfonate, sodium dioctylsulfosuccinate, sodium lauryl sulfate, alkylphenols, aliphatic alcohols and propylene oxide, Nonionic surfactants such as reaction products with ethylene oxide are shown. These surfactants may be used alone or in combination of two or more. Furthermore, if necessary, a cationic surfactant such as an alkylamine salt may be used.

  The amount of the initiator in the polymerization of the monomer mixture and the monomer mixture (A) in the acrylate-based crosslinked elastic particle (B) is selected from the acrylate-based crosslinked elastic particle (B) or (meth) acrylic. The range of 0.03 to 3.5 parts by weight is preferable with respect to 100 parts by weight of the acid alkyl ester monomer mixture (A), more preferably 0.1 to 2.5 parts by weight, and 0.2 to 1.5 parts by weight. Part by weight is more preferred. If the addition amount of an initiator is the said range, it is preferable from a viewpoint of the mechanical strength of the acrylic resin composition obtained, and a moldability.

  In the present invention, a chain transfer agent can be used to control the molecular weight of the polymer obtained by polymerizing the monomer mixture (A). Examples of the chain transfer agent include methyl mercaptan, ethyl mercaptan, isopropyl mercaptan, n-butyl mercaptan, tert-butyl mercaptan, n-hexyl mercaptan, n-octyl mercaptan, n-dodecyl mercaptan, ethylthioglycolate, mercaptoethanol, Thio-β-naphthol, thiophenol, dimethyl disulfide and the like are used. As a usage-amount of a chain transfer agent, the range of 0.02-2.2 weight part is preferable with respect to 100 weight part of (meth) acrylic-acid alkylester monomer mixture (A), 0.1-1.5 Part by weight is more preferable, and 0.2 to 1.0 part by weight is more preferable. If the usage-amount of a chain transfer agent exists in this range, it is preferable from a viewpoint of the mechanical strength of an acrylic resin composition obtained, and a moldability.

  In the present invention, the content of the acrylic ester-based crosslinked elastic particles (B) in the acrylic resin (C) is 5 to 40% by weight when the entire acrylic resin group (C) is 100% by weight. Is preferable, and 10 to 35% is more preferable. When the content of the acrylic ester-based crosslinked elastic particles (B) is in the above range, it is preferable from the viewpoint of molding processability and bending resistance of the obtained (meth) acrylic composition.

  When the acrylic resin (C) is obtained as a latex by emulsion polymerization or the like, the acrylic resin (C) is separated by operations such as coagulation, washing and drying, or by spray drying, freeze drying, etc. Can be recovered.

  The acid value of the thermoplastic resin (D) blended with the acrylic resin composition (E) in the present invention is preferably less than 0.7 mmol / g, and more preferably less than 0.6 mmol / g. If the acid value of the thermoplastic resin (D) is less than 0.7 mmol / g, it is preferable from the viewpoint of alkali resistance of the resulting (meth) acrylic resin composition.

  Examples of the thermoplastic resin (D) in the present invention include polyglutarimide, glutaric anhydride resin, lactone cyclized methacrylic resin, (meth) acrylic resin, styrene resin, methyl methacrylate-styrene copolymer, Examples thereof include polyethylene terephthalate resin and polybutylene terephthalate resin. Among these, a methacrylic resin is preferable from the viewpoint of compatibility with the acrylic resin (C), weather resistance, and transparency. When a (meth) acrylic resin is used as the thermoplastic resin (D) in the present invention, methacrylic acid alkyl ester 50 to 100% by weight, acrylic acid alkyl ester 0 to 50% by weight, and (meth) acrylic acid 0 to 6% by weight Is preferably obtained by copolymerizing a monomer mixture containing at least one or more stages, more preferably 60 to 100% by weight of methacrylic acid alkyl ester, 0 to 40% by weight of acrylic acid alkyl ester, and (meth). What contains 0 to 4 weight% of acrylic acid is more preferable. In particular, when emphasizing the hardness and rigidity of the resulting film, the monomer mixture composition of the methacrylic polymer (D) preferably contains 80% by weight or more of methyl methacrylate, and 85% by weight or more. What contains is more preferable, What contains 90 weight% or more is further more preferable, What contains 92 weight% or more is especially preferable.

  The blending ratio of the thermoplastic resin (D) is preferably in the range of 50 to 100 parts by weight of the acrylic resin (C) and 0 to 50 parts by weight of the thermoplastic resin (D) from the viewpoints of impact resistance and bending whitening. A range of 50 to 90 parts by weight of the acrylic resin (C) and 10 to 50 parts by weight of the thermoplastic resin (D) is more preferable, and 60 to 80 parts by weight of the acrylic resin (C) and 20 to 40 parts of the thermoplastic resin (D). A range of parts by weight is more preferred. The blending method is not particularly limited, and a known method can be used.

  When heat-treating acrylic resin compositions, commonly used weathering stabilizers such as antioxidants, heat stabilizers, light stabilizers, UV absorbers, radical scavengers, catalysts, plasticizers, lubricants, electrification An inhibitor, a colorant, an anti-shrink agent, an antibacterial / deodorant, and the like may be added alone or in combination of two or more, so long as the object of the present invention is not impaired. These additives can also be added when the acrylic resin composition is molded.

  The acid value of the acrylic resin composition in the present invention is preferably 0.2 to 0.7 mmol / g, and more preferably 0.3 to 0.6 mmol / g. It is preferable for the acid value of the acrylic resin composition to be 0.2 to 0.7 mmol / g, since the balance of sunscreen cream resistance and alkali resistance of the resulting film can be achieved.

  The glass transition temperature of the acrylic resin composition of the present invention is preferably 110 to 140 ° C, and more preferably 115 to 135 ° C. A glass transition temperature within this range is preferable from the viewpoints of moldability and heat resistance.

  The automotive acrylic film of the present invention is a film formed by molding the above (meth) acrylic resin composition.

  Examples of the production method (molding method) of the acrylic film for automobiles of the present invention include an ordinary melt extrusion method such as an inflation method, a T-die extrusion method, a calendar method, and a solvent casting method. In addition, when forming a film from a methacrylic resin composition, if necessary, by simultaneously bringing both surfaces of the film into contact with a roll or a metal belt, in particular, simultaneously with the roll or metal belt heated to a temperature equal to or higher than the glass transition temperature. By bringing them into contact, it is possible to obtain a film having a superior surface property. Further, depending on the purpose, film reforming by film lamination molding or biaxial stretching is also possible.

  The automotive acrylic film obtained from the (meth) acrylic resin composition of the present invention can be used by laminating on metal, plastic and the like. Examples of the laminating method include wet laminating, dry laminating, extrusion laminating, hot melt laminating, and the like, after applying an adhesive to a metal plate such as a steel plate, and then depositing the film on the metal plate and drying it.

  In the acrylic film for automobiles of the present invention, the surface hardness of the film is preferably H or more, and more preferably 2H or more. When the film surface hardness is less than H, the film tends to be easily damaged like the conventional acrylic. As a method of laminating a film on a plastic part, the film is placed in a mold, and film insert molding in which resin is filled by injection molding, laminate injection press molding, or after preforming the film in the mold. Examples include film-in-mold molding that is arranged and filled with resin by injection molding.

  The laminate laminate of an acrylic film for automobiles formed by molding the (meth) acrylic resin composition of the present invention can be used for automobile interior and exterior materials. Automobile interior materials are used for decorative parts of instrument panels, etc., and require transparency, high chemical resistance, bendability, and surface hardness. On the other hand, automobile exterior materials are used for bumpers, side garnishes, and the like, and are required to have transparency, chemical resistance, weather resistance, bendability, and surface hardness. Further, films used for automobile interior materials and exterior materials are required to have few surface scratches called die lines.

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the scope of claims, and can be obtained by appropriately combining technical means disclosed in different embodiments. Embodiments are also included in the technical scope of the present invention.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further in detail, this invention is not limited at all by these.

In the following production examples, examples and comparative examples, “parts” represents parts by weight, and “%” represents% by weight. Each abbreviation represents the following substance.
BA: butyl acrylate MMA: methyl methacrylate EHA: 2-ethylhexyl acrylate AlMA: allyl methacrylate CHP: cumene hydroperoxide tDM: tertiary lead decyl mercaptan

  In addition, each measuring method of the physical property measured in the following Examples and Comparative Examples is as follows.

(1) Evaluation of polymerization conversion rate
The resulting methacrylic resin composition (C) latex was dried in a hot air dryer at 120 ° C. for 1 hour to determine the amount of solid components, polymerization conversion (%) = 100 × solid component amount / charged monomer The polymerization conversion rate was calculated by the following formula.

(2) Evaluation of average particle diameter of latex)
Volume average particle diameter (μm) of the obtained acrylic ester-based crosslinked elastic particles (B) latex was measured by a light scattering method using MICROTRAC UPA150 manufactured by LEED & NORTHRUUP INSTRUMENTS.

(3) Measurement of acid value The acid value was measured according to the following procedure.
1) Titration of resin: 37.5 ml of methanol was added after dissolving 0.3 g of the obtained resin pellets in 37.5 ml of methylene chloride. Two drops of phenolphthalein / ethanol solution (1 wt%) were added to this solution. 5 ml of 0.1N sodium hydroxide aqueous solution was added and stirred for 1 hour. 0.1N hydrochloric acid was added dropwise to this solution, and the amount A (ml) of 0.1N hydrochloric acid was measured until the reddish purple color of the solution disappeared.
2) Blank titration: 2 drops of a phenolphthalein / ethanol solution (1 wt%) were added to 37.5 ml of methylene chloride and 37.5 ml of methanol. To this, 5 ml of 0.1N sodium hydroxide aqueous solution was added. To this solution, 0.1N hydrochloric acid was added dropwise, and a drop amount B (ml) of 0.1N hydrochloric acid until the reddish purple color of the solution disappeared was measured.
3) The acid value (total amount of acid and acid anhydride) in the resin was C (mmol / g), and the following formula was used.
C = 0.1 × (5-AB) /0.3

(4) Glass transition temperature (Tg)
Using 10 mg of the obtained resin pellets, a differential scanning calorimeter (DSC, manufactured by Shimadzu Corporation, DSC-50 type) was used and measured at a heating rate of 20 ° C./min in a nitrogen atmosphere. Determined by law.

(5) Weight average molecular weight Catalog values from various plasticizer manufacturers were adopted.

(6) Bending resistance and bending whitening property The obtained film was bent 180 degrees, and the change of the bent portion was visually evaluated.
○: Whitening is not observed at the bent portion.
X: Whitening is recognized in a bending part.
-: A crack occurs in the bent portion.

(7) Yellowness
A 50 mm × 50 mm test piece was cut out from the obtained film and measured using a spectroscopic color difference meter SE-2000 manufactured by Nippon Denshoku Industries Co., Ltd. according to the method described in 6.3 of JIS K7105-1981.
Moreover, the yellowness of the sheet | seat produced with the hot press method was used after converting into thickness 125micrometer.

(8) Chemical resistance <Alkali resistance>
The obtained film was immersed in a 0.1 M aqueous sodium hydroxide solution and allowed to stand at 55 ° C. for 4 hours, and changes in the test piece were observed visually.
○: No change is observed Δ: Minor deterioration is observed ×: Deterioration and discoloration of the resin are observed <xylene resistance>
One drop (0.02 g) of xylene was dropped on the obtained film, left to dry at room temperature, and the change of the dropping part was visually observed.
○: No change is observed.
(Triangle | delta): A fine coating trace is recognized.
X: Deterioration and discoloration of the resin are observed.
<Toluene resistance>
One drop (0.02 g) of toluene was dropped on the obtained film, left to dry at room temperature, and the change of the dropping portion was visually observed.
○: No change is observed.
(Triangle | delta): A fine coating trace is recognized.
X: Deterioration and discoloration of the resin are observed.
<Sunproofing Agent [Copatone (Registered Trademark)] Property (Test Method 1)>
A small amount of sunscreen (Copatone Water Baby Lotion SPF50) is applied to the obtained film, gauze is pressed onto it, and a weight of 500 g is applied. The mixture was allowed to stand at room temperature for 1 hour, then heated in an oven at 74 ° C., 64 ° C. or 54 ° C. for 1 hour, and the adhered sunscreen was wiped off with gauze.
○: No change is observed.
(Triangle | delta): A fine coating trace is recognized.
X: Deterioration and discoloration of the resin are observed.
<Sunproofing Agent [Copatone (registered trademark)] (Test Method 2)>
One drop (0.005 g) of sunscreen agent (Copatone Water Baby Lotion SPF50) was added dropwise to the resulting film, and it was extended to a range of 2 x 3 cm with a brush, and left to stand at 90 ° C for 24 hours. The stopper was wiped off with gauze, and changes in the coated part were observed visually.
○: No change is observed.
(Triangle | delta): A fine coating trace is recognized.
X: Deterioration and discoloration of the resin are observed.

(9) Transparency (haze)
The obtained test piece was measured by using a turbidimeter NDH-300A manufactured by Nippon Denshoku Industries Co., Ltd. according to the method described in 6.4 of JIS K7105-1981.

(10) Film surface hardness It measured according to the method of JISK5600-5-4 on the obtained test piece.

(Production Example 1) Production of (meth) acrylic resin (C) Production of acrylic resin (C) The following substances were charged into an 8 L polymerization apparatus equipped with a stirrer.
Deionized water 200 parts Sodium dioctylsulfosuccinate 0.25 parts Sodium formaldehyde sulfoxylate 0.15 parts Ethylenediaminetetraacetic acid-2-sodium 0.005 parts Ferrous sulfate 0.0015 parts Nitrogen gas in the polymerization machine And the inside temperature is set to 60 ° C., and the monomer mixture used as a raw material for the acrylate-based crosslinked elastic particles (B) [ie, BA 90% and MMA 10% 30 parts of a monomer mixture consisting of 2.1 parts of AlMA and 0.2 part of CHP] was continuously added at a rate of 10 parts / hour to 100 parts of the monomer mixture consisting of Polymerization was continued for 5 hours to obtain acrylic ester-based crosslinked elastic particles (B). The polymerization conversion was 99.5% and the average particle size was 800 mm. Thereafter, 0.3 part of sodium dioctylsulfosuccinate was charged, the internal temperature was adjusted to 60 ° C., and the (meth) acrylic acid alkyl ester monomer mixture (A) [that is, a single amount comprising BA 1%, MMA 99% 70 parts of monomer mixture consisting of 0.34 parts of tDM and 0.34 parts of CHP to 100 parts of the body mixture] was continuously added at a rate of 10 parts / hour, and the polymerization was continued for 1 hour to obtain an acrylic resin. (C) was obtained. The polymerization conversion rate was 99.0%. The obtained latex was salted out and coagulated with calcium chloride, washed with water and dried to obtain a powdery acrylic resin (C).

  Table 1 shows the physical properties of the plasticizers used in the examples and comparative examples. The JONCRYL (registered trademark) series is manufactured by BASF, and the ARUFON (registered trademark) series is manufactured by Toagosei Co., Ltd.

Moreover, the following were used as the thermoplastic resin (D) to blend.
・ Methacrylic resin HT121 [manufactured by ALTUGLASS, acid value 0.45 mmol / g]
-Methacrylic resin Sumipex LG [manufactured by Sumitomo Chemical Co., Ltd., acid value 0 mmol / g].

(Examples 1 to 15)
After dry blending the acrylic resin (C) resin powder, the thermoplastic resin (D) and the plasticizer in the types and ratios shown in Table 2, the cylinder temperature is set to 260 ° C. using a single-screw extruder with a 40 mmφ vent. It was set and melt kneaded to obtain a pelletized acrylic resin composition.
The properties of the obtained acrylic resin composition were evaluated, and the results are shown in Table 2 together with the acid value of the acrylic resin composition.
Furthermore, the obtained (meth) acrylic resin composition was molded at a die temperature of 260 ° C. using a 40 mmφ extruder with a T die to obtain a film having a thickness of 125 μm.
The properties of the obtained film were evaluated, and the results are shown in Table 2.
Acrylic resins of Examples 1 to 15 using a plasticizer having an acid value of 0.3 to 5.5 mmol / g, a weight average molecular weight of 3000 to 30000, and a Tg of 40 to 115 ° C. A film formed by molding the composition has improved chemical resistance and high film surface hardness.

(Comparative Examples 1-8)
Acrylic resin (C) resin powder, thermoplastic resin (D) and plasticizer are dry blended in the types and proportions shown in Table 2, and the cylinder temperature is set to 260 ° C using a 40 mmφ vented single screw extruder. Then, melt kneading was performed to obtain a pelletized acrylic resin composition.
The properties of the obtained acrylic resin composition were evaluated, and the results are shown in Table 3 together with the acid value of the acrylic resin composition.
An acrylic resin composition using a plasticizer having an acid value of 0.3 to 5.5 mmol / g, a weight average molecular weight of 3000 to 30000, and a Tg of 40 to 115 ° C. Films formed by molding Comparative Examples 1 to 7) have poor xylene resistance and sunscreen resistance. Moreover, the acrylic resin composition (Comparative Example 8) in which the plasticizer under the above conditions is blended outside the range of 1 to 15 parts by weight is inferior in transparency, alkali resistance, and fragrance resistance.
Also, a film with improved chemical resistance and high film surface hardness could not be obtained.

Claims (9)

1 plasticizer having an acid value of 0.3 to 5.5 mmol / g, a weight average molecular weight of 3000 to 30000, and a glass transition temperature of 40 to 115 ° C. with respect to 100 parts by weight of the acrylic resin composition (E). A film for an automobile formed by molding an acrylic resin composition containing -15 parts by weight,
Acrylic resin composition (E)
Two or more non-conjugated double bonds per molecule per 100 parts by weight of a monomer mixture containing 50 to 100% by weight of an acrylic acid alkyl ester monomer and 0 to 50% by weight of a methacrylic acid alkyl ester monomer In the presence of acrylic ester-based crosslinked elastic particles (B) obtained by mixing and polymerizing 0.5 to 5 parts by weight of a polyfunctional monomer having
An automobile comprising an acrylic resin (C) obtained by polymerizing a monomer mixture (A) containing 50 to 100% by weight of methacrylic acid alkyl ester and 0 to 50% by weight of acrylic acid alkyl ester Acrylic film. Acrylic resin composition (E)
The acrylic film for automobiles according to claim 1, further comprising a thermoplastic resin (D) having an acid value of less than 0.7 mmol / g.   The acrylic resin composition (E) comprises 50 to 99% by weight of the acrylic resin (C) and 0 to 50% by weight of the thermoplastic resin (D) [the total of (C) and (D) is 100% by weight. 3. The acrylic film for automobiles according to claim 1, wherein the acrylic film is for automobiles.   The acrylic film for automobiles according to any one of claims 1 to 3, wherein the acid value of the acrylic resin composition is 0.2 to 0.7 mmol / g.   The acrylic film for motor vehicle interiors in any one of Claims 1-4.   The acrylic film for vehicle exteriors in any one of Claims 1-4.   A laminate obtained by laminating the automobile acrylic film according to claim 1.   An automotive interior part obtained by laminating the automotive interior acrylic film according to claim 5.   An automotive exterior part obtained by laminating the automotive exterior acrylic film according to claim 6.