JP5616084B2 - Rubber-modified acrylic resin composition with excellent jetness and molded product thereof - Google Patents

Description

  The present invention relates to a rubber-modified acrylic resin composition that is not only excellent in weather resistance, impact resistance, appearance, and moldability, but also excellent in jetness, and a molded body using the resin composition.

  Acrylic resins based on polymethyl methacrylate have excellent weather resistance, gloss and transparency, but there is nothing that satisfies impact resistance, weather resistance and jet blackness at the same time, and the range of use is limited. It has been.

  As a method for imparting impact resistance while maintaining the excellent weather resistance of such a methacrylic resin, a method of mixing graft copolymers having various multilayer structures has been proposed. An outline of typical methods (a), (b), and (c) will be described below.

  In addition, the weather resistance, gloss, impact resistance, and workability described below indicate the properties relating to a methacrylic resin composition obtained by mixing a methacrylic resin alone or a methacrylic resin with a graft copolymer.

  (A) In order to provide impact resistance while maintaining the excellent weather resistance of methacrylic resin, a rubbery polymer having an acrylic acid alkyl ester having excellent weather resistance as a main component and having a glass transition temperature of room temperature or less A rubber-like heavy polymer obtained by graft polymerization of a monomer component (hereinafter referred to as a hard monomer component) such as a methacrylic acid alkyl ester having a glass transition temperature of room temperature or higher and which can be a structural unit of a relatively hard polymer. It has been proposed to mix a graft copolymer having a two-layer structure of a polymer-hard polymer (Patent Documents 1 and 2).

  (B) A rubber-like polymer mainly composed of alkyl acrylate is formed on the outer shell of a hard polymer containing 70 to 100% (% by weight, the same applies hereinafter) of a hard monomer component such as alkyl methacrylate. Furthermore, it is proposed that a graft copolymer having a three-layer structure of a hard polymer-rubbery polymer-hard polymer obtained by graft polymerization of a hard monomer component such as an alkyl methacrylate to the outer shell is proposed. (Patent Document 3).

  (C), (b) A semi-rubber-like glass transition temperature close to room temperature by copolymerizing 35 to 45% of an acrylic acid alkyl ester with a hard monomer component such as an alkyl methacrylate that is the innermost layer of the method. And a semi-rubbery polymer cross-linked with a cross-linkable monomer having two or more acryloyloxy groups and / or methacryloyloxy groups in one molecule, and an acrylic acid alkyl ester in the outer shell. A graft copolymer having a three-layer structure of semi-rubber-rubber-hard is formed by forming a rubber-like polymer having a main component and graft polymerization of a hard monomer component such as alkyl methacrylate on the outer shell. A method of mixing a polymer has been proposed (Patent Document 4).

  Further, a jet black composition containing a 1: 2 chromium complex of a mono-azo dye substituted with amino-phenol and bonded to 2-naphthol in a thermosetting acrylic resin is known (Patent Document 5). There is a problem with light resistance.

U.S. Pat. No. 3,808,180 U.S. Pat. No. 3,843,753 U.S. Pat. No. 3,793,402 JP-A-62-230841 Japanese Patent Publication No. 06-089279

  The present invention has been made for the purpose of obtaining a methacrylic resin composition excellent in all of weather resistance, gloss, jet blackness, impact resistance, and processability.

  In the acrylic resin to which a dye such as an azo compound is added in order to obtain jetness as in Patent Document 5, the weather resistance of the base resin affected by the weather resistance of the dye itself or the presence of the dye. In order to solve such a problem, it has been found that it is difficult to obtain an acrylic resin excellent in jet blackness and weather resistance due to a decrease in properties. We found carbon black as a low-impact jet black material, and as a result of intensive investigations on how to obtain excellent jet blackness in the combination of this carbon black and acrylic resin, carbon was added to transparent rubber-modified acrylic resin. The present invention finds that the above problem can be solved by blending black and dispersing in the resin composition so that the particle size of carbon black is 10 to 40 nm. It has been completed.

That is, the present invention is a resin composition obtained by blending carbon black (B) with a rubber-modified acrylic resin (A) having transparency and having a total light transmittance of 85% or more of a molded product having a thickness of 3 mm. ,
The present invention relates to a jet black rubber-modified acrylic resin composition, wherein the carbon black dispersed in the resin composition has a particle size of 10 to 40 nm.

In a preferred embodiment, 100 parts by weight of the rubber-modified acrylic resin (A) is
Rubber containing acrylic graft copolymer (A1) 5 to 100 parts by weight, and acrylic resin (A2) 95 to 0 parts by weight,
The rubber-containing acrylic graft copolymer (A1) has an inner layer of the rubber copolymer (A1c) and an outer layer of the graft component (A1s) covering the inner layer, and the weight ratio of A1c: A1s is 5:95 to 85. : A multilayer structure graft copolymer comprising 15;
The rubber copolymer (A1c) is an acrylic acid alkyl ester of 50 to 99.9% by weight, another copolymerizable vinyl monomer of 0 to 49.9% by weight, and a polyfunctional monomer of 0.1%. A polymer of 100% by weight of a monomer for rubber copolymer consisting of 10% by weight,
The graft component (A1s) is composed of 50 to 100% by weight of methacrylic acid alkyl ester and 100% by weight of graft component monomer consisting of 0 to 50% by weight of vinyl monomer other than copolymerizable alkyl methacrylate. A polymer, and
The rubber-modified acrylic resin composition, wherein the acrylic resin (A2) is a polymer of an acrylic resin monomer comprising an acrylic acid alkyl ester of 0 to 50% by weight and a methacrylic acid alkyl ester of 100 to 50% by weight. It is to do.
The composition of the present invention preferably contains, as described above, a specific rubber that is well dispersed in the base resin together with the carbon black according to the present invention and is excellent in the effect of imparting transparency and impact resistance. Since the acrylic graft copolymer is contained in a specific amount, not only the light resistance is excellent, but also the possibility that the base resin is hydrolyzed is reduced, so that the water resistance is also excellent.
A preferred embodiment is that the rubber-containing acrylic graft copolymer (A1) has a number average particle diameter of 30 to 400 nm.
In a preferred embodiment, the rubber-containing acrylic graft copolymer (A1) further comprises an innermost layer polymer (A1a) having a weight ratio of A1a: (total amount of A1c and A1s) of 10: 90-40. : 60, and
A multilayered graft copolymer having at least a three-layer structure obtained by polymerizing the rubber copolymer monomer in the presence of the innermost layer polymer (A1a); and
The innermost layer polymer (A1a) is one or more selected from the group consisting of methacrylic acid alkyl ester and aromatic vinyl, and 40 to 99.9% by weight, and other vinyl monomers copolymerizable 59.9. The rubber-modified acrylic resin composition, which is a polymer of 100% by weight of an innermost layer polymer monomer consisting of ˜0% by weight and 0.1 to 5% by weight of a polyfunctional monomer. That is.
Moreover, this invention relates to the molded object formed by shape | molding the resin composition of this invention.
Further, the present invention is a molded product formed by molding the resin composition of the present invention, and a flat molded product injection-molded with a mirror-finished mold is subjected to a 0-45 degree post-spectral method as defined in JISZ-8722. The L-value is in the range of 0 to 8 when measured with a color difference meter.
Further, the present invention is a molded product formed by molding the resin composition of the present invention, and a flat molded product injection-molded with a mirror-finished mold is defined in JIS K 7350-4, black panel 63 ° C., It relates to a molded article characterized in that a change in L value in a color difference meter before and after the test was conducted in a weather resistance test for 1000 hours under a condition of 255 W / m ² in the range of 0 to 1 with rain.

  The resin composition of the present invention is a methacrylic resin composition excellent in all of weather resistance, gloss, jet blackness, and impact resistance.

(Rubber-modified acrylic resin composition)
The rubber-modified acrylic resin composition of the present invention is a resin composition excellent in jetness formed by blending carbon black (B) with a rubber-modified acrylic resin (A), and the jet jet black according to the present invention The rubber-modified acrylic resin (A) has transparency that the total light transmittance of the molded product having a thickness of 3 mm is 85% or more, and the carbon black dispersed in the resin composition This is an effect that is specifically exhibited by the two factors that the particle size of is 10 to 40 nm.

  The addition amount of the carbon black according to the present invention is 0.05 to 10 parts by weight with respect to 100 parts by weight of the rubber-modified acrylic resin (A) according to the present invention from the viewpoint of imparting sufficient jet blackness. More preferably, it is 0.1 to 5 parts by weight, and even if it exceeds 10 parts by weight, the jetness is saturated, which is not economical.

(Molded body)
Since the rubber-modified acrylic resin composition of the present invention is excellent in molding processability, it can be used for automobile parts, electrical / electronic parts, miscellaneous goods, film, etc. by known thermoplastic resin molding methods such as injection molding and extrusion molding. Or the like. This molded article of the present invention is not only excellent in weather resistance, impact resistance, appearance, and molding processability, but also excellent in jet blackness and gloss, and thus is suitable as an appearance member that requires a high-grade appearance, for example. Yes, as such an appearance member, it is suitable for a vehicle member, a household electrical appliance member, and a film application.

(Rubber-modified acrylic resin (A))
As described above, the rubber-modified acrylic resin (A) according to the present invention requires that the 3 mm-thick molded article has transparency with a total light transmittance of 85% or more, and obtains excellent impact strength. From the viewpoint, the total amount is 100 weights, preferably 5 to 100 parts by weight of the rubber-containing acrylic graft copolymer (A1) and 95 to 0 parts by weight of the acrylic resin (A2).

(Carbon black (B))
From the viewpoint of imparting sufficient jet blackness to the rubber-modified acrylic resin composition of the present invention, the carbon black according to the present invention has an average particle size when dispersed in the resin, that is, a dispersed particle size of 10 to 40 nm. It needs to be. The dispersed particle diameter is more preferably 10 to 30 nm. The dispersed particle size is more preferably 10 to 25 nm. The dispersed particle size is most preferably 10 to 20 nm. Those having an average particle diameter exceeding 40 nm are not preferable because they do not show sufficient jetness, and those having an average particle diameter of less than 10 nm are generally difficult to obtain, although they have excellent ability to impart jetness. . In the present invention, the average particle diameter is obtained by observing carbon black aggregates with an electron microscope, measuring the size of a component that has a contour and cannot be separated, and arithmetically averages N = 50. Carbon black can be supplied in powder or granular form, but instead of adding it as it is, a so-called masterbatch pigment is used in which an acrylic resin and high-concentration carbon black are premixed and pulverized. Is preferable from the viewpoint of dispersibility of carbon black.

  Examples of such carbon black used in the present invention are those having a blackness higher than MCF (Medium Color Furnace), which is a general name of carbon black for coloring (HCF: High Color Channel, HCC: High Color Channel). # 2600, # 980, # 960 (Mitsubishi Chemical), Talker Black # 8500, # 7400, # 7350, # 7100 (Tokai Carbon), Color Black FW200, FW2, S170, Printex 90, 80 (Degussa), Raven 7000, 5750, 3500 (Colombian Chemicals), Monarch 1400, 1300, 900, 800, Black Pearls 1400 1300,900,800, although Vulcan P (manufactured by Cabot Corporation), and the like, but is not limited thereto.

(Rubber-containing acrylic graft copolymer (A1))
From the viewpoint of obtaining excellent impact strength and transparency, the rubber-containing acrylic graft copolymer (A1) according to the present invention comprises an inner layer of the rubber copolymer (A1c) and a graft component (A1s) that covers the inner layer. It is preferable that the outer layer is a multilayer structure graft copolymer including an A1c: A1s weight ratio of 5:95 to 85:15. From the viewpoint of obtaining particularly excellent impact strength, the innermost layer polymer is further used. (A1a) is included so that the weight ratio of A1a: (total amount of A1c and A1s) is 10:90 to 40:60, and in the presence of the innermost layer polymer (A1a), the rubber It is more preferable to use a multi-layered graft copolymer having at least a three-layer structure in which a copolymer monomer is polymerized.

  The weight ratio of A1c: A1s is more preferably 25:75 to 80:20 from the viewpoint of further increasing the impact strength.

  The number average particle diameter of such a rubber-containing acrylic graft copolymer (A1) is preferably 30 to 400 nm, more preferably 40 to 300 nm, from the viewpoint of balancing impact resistance and transparency. is there.

  There is no particular limitation on the method for producing such a rubber-containing acrylic graft copolymer (A1), and for example, suspension polymerization method, emulsion polymerization method and the like can be used. Therefore, it is preferable to produce by an emulsion polymerization method.

(Acrylic resin (A2))
The acrylic resin (A2) according to the present invention includes the rubber copolymer (A1c) and the carbon black (B) according to the present invention as a base resin of the composition of the present invention together with the graft component (A1s). From the viewpoint of obtaining excellent transparency, a continuous layer resin to be wrapped, that is, a component functioning as a matrix resin, preferably from 0 to 50% by weight of alkyl acrylate ester and from 100 to 50% by weight of alkyl methacrylate ester It is a polymer of a monomer for acrylic resin.

  There are no particular limitations on the method for producing such an acrylic resin (A2). For example, a suspension polymerization method, an emulsion polymerization method, or the like can be used, but methacrylic acid alkyl ester and acrylic acid alkyl ester are efficiently copolymerized. From the viewpoint, the suspension polymerization method is preferable.

(Rubber copolymer (A1c))
The rubber copolymer (A1c) is a component mainly responsible for the impact resistance improving effect according to the present invention due to its rubber elasticity, and its refractive index is the refractive index of the graft component (A1s) or acrylic resin (A2). The closer to the ratio and the smaller the particle size, the more easily the transparency becomes. The number average particle size of such a rubber copolymer (A1c) is 30 from the viewpoint of balancing impact resistance and transparency. It is preferable to set it to -400 nm, More preferably, it is 40-300 nm.

  Further, such a rubber copolymer (A1c) is preferably 50 to 99.9% by weight of an acrylic acid alkyl ester, from the viewpoint of obtaining excellent impact strength and transparency, and other than the copolymerizable acrylic acid alkyl ester. A polymer of 100% by weight of a monomer for a rubber copolymer consisting of 0 to 49.9% by weight of a vinyl monomer and 0.1 to 10% by weight of a polyfunctional monomer, more preferably, Rubber copolymer comprising 70 to 99% by weight of acrylic acid alkyl ester, 0 to 29% by weight of vinyl monomer other than copolymerizable acrylic acid alkyl ester, and 0.1 to 5% by weight of polyfunctional monomer It is a polymer of 100% by weight of monomer for use.

(Graft component (A1s))
The graft component (A1s) is a continuous layer that wraps the rubber copolymer (A1c) and the carbon black (B) according to the present invention as the base resin of the composition of the present invention together with the acrylic resin (A2). Resin, that is, a component functioning as a matrix resin, and from the viewpoint of obtaining excellent impact strength, transparency, and moldability, preferably 50 to 100% by weight of alkyl methacrylate and copolymerizable methacryl It is a polymer of 100% by weight of a monomer for graft component consisting of 0 to 50% by weight of vinyl monomer other than acid alkyl ester, and more preferably 80 to 100% by weight of methacrylic acid alkyl ester and copolymerizable Polymer of 100% by weight of graft component monomer comprising 20 to 0% by weight of vinyl monomer other than methacrylic acid alkyl ester A. From the viewpoint of improving the fluidity of the composition of the present invention and improving the molding processability, the graft component monomer is added to 100% by weight, and a mercaptan compound such as dodecyl mercaptan and octyl mercaptan is further added in an amount of 0.01 to 5% by weight. It is preferable to add.

  The graft component (A1s) itself may have a multilayer structure as necessary.

(Innermost layer polymer (A1a))
The innermost layer polymer (A1a) is a component added to the rubber-containing acrylic graft copolymer (A1) in order to further improve the impact strength and transparency of the resin composition of the present invention. Preferably, one or more selected from the group consisting of alkyl methacrylates and aromatic vinyl, 40 to 99.9% by weight, and other copolymerizable vinyl monomers 59.9 to 0% by weight, It is a polymer composed of 0.1 to 5% by weight of a polyfunctional monomer and 100% by weight of the monomer for the innermost layer polymer, more preferably an alkyl methacrylate and an aromatic vinyl. An innermost layer comprising 55 to 90% by weight of at least one selected from the group, 45 to 10% by weight of another copolymerizable vinyl monomer, and 0.1 to 5% by weight of a polyfunctional monomer 100% by weight of polymer monomer That. In the presence of the innermost layer polymer (A1a), the rubber copolymer monomer is polymerized, so that the rubber-containing acrylic graft copolymer (A1) is generally distributed in the center thereof. It becomes a layer to do.

(Acrylic acid alkyl ester)
As the alkyl acrylate ester, those having 1 to 8 carbon atoms in the alkyl group are preferable from the viewpoint of the reaction rate at the time of polymerization. For example, methyl acrylate, ethyl acrylate, propyl acrylate, acrylic acid Examples thereof include butyl (BA), 2-ethylhexyl acrylate (2EHA), and acrylate-n-octyl (nOA). From the viewpoint of improving impact resistance according to the present invention, BA, 2EHA, and nOA are used. One or more selected from the group is preferred, and BA is particularly preferred. These may be used alone or in combination of two or more. The alkyl group of the acrylic acid alkyl ester may be linear or branched.

(Methacrylic acid alkyl ester)
As the alkyl methacrylate, those having 1 to 4 carbon atoms in the alkyl group are preferable from the viewpoint of the reaction rate during polymerization, for example, methyl methacrylate, ethyl methacrylate, propyl methacrylate, methacrylic acid. Although butyl etc. are mentioned, From a viewpoint of improving the workability which concerns on this invention, Preferably it is methyl methacrylate. The alkyl group of the methacrylic acid alkyl ester may be linear or branched.

(Aromatic vinyl)
The aromatic vinyl is preferably at least one selected from the group consisting of styrene, α-methylstyrene, and vinyltoluene, and more preferably styrene.

(Polyfunctional monomer)
The polyfunctional monomer is a monomer having two or more non-conjugated double bonds per molecule, and is a component that functions as a crosslinking agent or a graft crossing agent. One or more selected from the group consisting of glycol di (meth) acrylates, vinyl group-containing polyfunctional monomers, and allyl group-containing polyfunctional monomers are preferred.

  Examples of the alkylene glycol di (meth) acrylates include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, and dibutylene glycol di (meth) acrylate.

  In this specification, (meth) acrylic acid ester means acrylic acid ester and / or methacrylic acid ester.

  Examples of the vinyl group-containing polyfunctional monomers include divinylbenzene and divinyl adipate.

  Examples of the allyl group-containing polyfunctional monomers include allyl (meth) acrylate, diallyl phthalate, triallyl cyanurate, triallyl isocyanurate, and the like.

(Vinyl monomer)
Examples of the vinyl monomer that can be used in the present invention include aromatic vinyl such as styrene, α-methylstyrene, and vinyl toluene, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, Non-alkyl (meth) acrylates such as (meth) acrylic acid alkyl esters such as (meth) butyl acrylate, phenyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, (meth) acrylonitrile, (meth) Acrylic acid etc. are mentioned.

(UV absorber)
From the viewpoint of further improving the weather resistance, the ultraviolet absorbent is added to the resin composition of the present invention in an amount that does not affect the total light transmittance of the molded product, that is, the rubber-modified acrylic resin (A) according to the present invention. It is preferable to add 0.1-15 weight part with respect to 100 weight part, More preferably, it is 0.2-5 weight part.

  The ultraviolet absorber is preferably at least one selected from the group consisting of benzotriazole-based, triazine-based, and benzophenone-based ultraviolet absorbers from the viewpoint of ultraviolet absorbing ability.

  Examples of the benzotriazole ultraviolet absorber include 2- (2-hydroxy-5-methylphenyl) benzotriazole, 2- [2-hydroxy-5- (1,1,3,3-tetramethylbutyl) Phenyl] benzotriazole, 2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] benzotriazole, 2- (2′-hydroxy-3-tert-butyl-5′-methylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy-3,5-di-tert-amylphenyl) benzotriazole, 2- (2-hydroxy-3-sec-butyl-5-tert-butylphenyl) benzotriazole 2,2′-methylenebis [6- (2H-benzotriazol-2-yl) -4- (1,1,3,3-tetra Methylbutyl) phenol], 2- (2-hydroxy-5-methyl-3-dodecylphenyl) benzotriazole, and the like. Examples of the benzophenone-based ultraviolet absorber include 2-hydroxy-4-phenylmethoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfoxytrihydrate benzophenone, 2-hydroxy-4-phenylpropoxybenzophenone, and the like. Examples of triazine-based UV absorbers include 2- (4,6 diphenyl-1, 3,5-triazin-2-yl) -5-[(hexyl) oxy] -phenol and the like.

(Light stabilizer)
From the viewpoint of further improving the weather resistance, 0.1 to 3 parts by weight of a light stabilizer is added to the resin composition of the present invention with respect to 100 parts by weight of the rubber-modified acrylic resin (A) according to the present invention. Is preferred.

  The light stabilizer is not particularly limited, and a known light stabilizer can be used. For example, 2,2,6,6-tetramethyl-4-piperidyl stearate, 2,2,6,6-tetramethyl -4-piperidylbenzoate, 1,2,2,6,6-pentamethyl-4-piperidyl stearate, N- (2,2,6,6-tetramethyl-4-piperidyl) dodecyl succinimide, 1,2 , 2,6,6-pentamethyl-4-piperidylbenzoate, 1,2,2,6,6-pentamethyl-4-piperidyl methacrylate, bis (2,2,6,6-tetramethyl-4-piperidyl) Sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, bis (1-octoxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate Bis (2,2,6,6-tetramethyl-4-piperidyl) -bis (tridecyl) -1,2,3,4-butanetetracarboxylate, bis (1,2,2,6,6- Pentamethyl-4-piperidyl) bis (tridecyl) -1,2,3,4-butanetetracarboxylate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) -2-butyl-2- (3,5-ditert-butyl-4-hydroxyphenylmethyl) malonate, tetrakis (2,2,6,6-tetramethyl-4-piperidyl) -1,2,3,4-butanetetracarboxylate, tetrakis (1,2,2,6,6-pentamethyl-4-piperidyl) -1,2,3,4-butanetetracarboxylate, 3,9-bis [1,1-dimethyl-2- [tris (2, 2, , 6-tetramethyl-4-piperidyloxycarbonyloxy) butylcarbonyloxy] ethyl] -2,4,8,10-tetraoxaspiro [5.5] undecane, 3,9-bis [1,1-dimethyl- 2- [Tris (1,2,2,6,6-pentamethyl-4-piperidyloxycarbonyloxy) butylcarbonyloxy] ethyl] -2,4,8,10-tetraoxaspiro [5.5] undecane, -[(3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxyethyl] -2,2,6,6-tetramethyl-4-piperidyl- (3,5-di-tert-butyl-4 -Hydroxyphenyl) propionate, 1- (2-hydroxyethyl) -2,2,6,6-tetramethyl-4-piperidinol / dimethyl succinate 2-tert-octylamino-4,6-dichloro-s-triazine / N, N′-bis (2,2,6,6-tetramethyl-4-piperidyl) hexamethylenediamine condensate, N, N′-bis (2,2,6,6-tetramethyl-4-piperidyl) hexamethylenediamine / dibromoethane condensate, 2,2,6,6-tetramethyl-4-hydroxypiperidine-N-oxyl, 1 , 6-bis (2,2,6,6-tetramethyl-4-piperidylamino) hexane / dibromoethane polycondensate, 1,6-bis (2,2,6,6-tetramethyl-4-piperidylamino) ) Hexane / 2,4-dichloro-6-tert-octylamino-s-triazine polycondensate, 1,6-bis (2,2,6,6-tetramethyl-4-piperidylamino) hexane / 2 , And the like 4-dichloro-6-morpholino -s- triazine polycondensate.

(Other additives)
Various antioxidants and colorants other than carbon black can be added to the resin composition of the present invention as necessary.

  Next, the present invention will be described based on specific examples, but these are all illustrative and do not limit the contents of the present invention.

(Polymerization of rubber copolymer A1c-1)
250.0 parts by weight of ion-exchanged water, 0.5 parts by weight of potassium stearate, 0.2 parts by weight of sodium formaldehydesulfoxylate, 0.01 parts by weight of sodium ethylenediaminetetraacetate, and ferrous sulfate / 7 water salt 005 parts by weight was charged into a glass reactor and heated to 40 ° C. while stirring in a nitrogen stream. 84 parts by weight of n-butyl acrylate (BA), 15 parts by weight of styrene (ST), and allyl methacrylate (ALMA) ) A mixture consisting of 1 part by weight of a monomer for rubber copolymer and 0.1 part by weight of cumene hydroperoxide (CHP) was added dropwise over 4 hours. Simultaneously with the dropping, 40 parts by weight of a 5 wt% aqueous potassium stearate solution (2 parts by weight of potassium stearate) was continuously added over 4 hours. After completion of the addition, stirring was continued for 1.5 hours to complete the polymerization, thereby obtaining a latex of rubber copolymer A1c-1. The polymerization conversion rate was 98% (polymerization amount / monomer charge amount × 100%), and the number average particle diameter of the rubber copolymer particles in the latex of the obtained rubber copolymer A1c-1 was 70 nm (546 nm). It was obtained using light scattering at a wavelength).

(Polymerization of rubber copolymer A1c-2)
In the above (polymerization of rubber copolymer A1c-1), 0.5 part by weight of potassium stearate is changed to 0.05 part by weight of potassium stearate, and the monomer for rubber copolymer is changed to BA99. 10 parts by weight and a mixture of 0.1 part by weight of ALMA and 0.1 parts by weight of cumene hydroperoxide for the rubber copolymer, and after addition for 1 hour, the remaining 90% It was added dropwise over 4 hours, and simultaneously with the addition, 30 parts by weight of a 5 wt% aqueous potassium stearate solution (1.5 parts by weight of potassium stearate) was continuously added over 4 hours. A latex of rubber copolymer A1c-2 was obtained in the same manner except that the stirring was continued for a while to complete the polymerization. The polymerization conversion rate is 97.5% (polymerization amount / monomer charge amount × 100%), and the number average particle diameter of the rubber copolymer particles in the latex of the obtained rubber copolymer A1c-2 is 220 nm ( Obtained using light scattering at a wavelength of 546 nm).

(Production of rubber-containing acrylic graft copolymers A1-1 to A1-4)
220.0 parts by weight of ion-exchanged water, parts by weight of the rubber copolymer latex shown in Table 1 as shown in Table 1, 0.05 parts by weight of sodium formaldehydesulfoxylate, 0.01 parts by weight of sodium ethylenediaminetetraacetate, In addition, 0.005 part by weight of ferrous sulfate and heptahydrate was charged into a glass reactor and stirred in a nitrogen stream to obtain an aqueous dispersion, which was heated to 60 ° C. while maintaining the state. There, the graft composition shown in Table 1, ie, methyl methacrylate (MMA), BA, and methyl acrylate (MA), which are monomers for the graft component, CHP, and normal-dodecyl mercaptan, which are polymerization initiators. (N-DM) and a mixture of parts by weight shown in Table 1 were continuously added over 2 hours. After completion of the addition, 0.01 parts by weight of CHP was further added and stirring was continued for 1 hour to complete the polymerization, whereby latexes of rubber-containing acrylic graft copolymers A1-1 to A1-4 were obtained. The polymerization conversion rate was 99%. The obtained rubber-containing acrylic graft copolymer had a multilayer structure consisting of an inner layer of the rubber copolymer (A1c) and an outer layer of the graft component (A1s) covering the inner layer. These latexes were subjected to salting out coagulation, heat treatment, and drying by a known method to obtain rubber-containing acrylic graft copolymers A1-1 to A1-4 as white powders.

  In the production of the latex of A1-4, during the addition over 2 hours of the mixture of the graft composition comprising the above-mentioned monomer for graft component and the polymerization initiator, that is, 1 hour after the start of addition, 0.5 parts by weight of potassium acid was added.

(Production of rubber-containing acrylic graft copolymer A1-5 to A1-8 having a three-layer structure)
In order to polymerize the innermost layer polymer (A1a), 220.0 parts by weight of ion exchange water, 0.3 part by weight of boric acid, 0.03 part by weight of sodium carbonate, 0.09 part by weight of sodium N-lauroyl sarcosinate, formaldehyde A glass reactor was charged with 0.09 part by weight of sodium sulfoxylate, 0.006 part by weight of sodium ethylenediaminetetraacetate, and 0.002 part by weight of ferrous sulfate and heptahydrate. First, 25% of the inner layer polymer monomer shown in Table 2 and the inner layer component mixture consisting of 0.1 part by weight of t-butyl hydroperoxide are collectively collected after the temperature is raised to ° C. The polymerization was carried out for 45 minutes. Subsequently, the remaining 75% of the mixture was continuously added over 1 hour. After completion of the addition, the latex of the innermost layer polymer (A1a) of the rubber-containing acrylic graft copolymer A1-5 to A1-8 having a three-layer structure was obtained by maintaining the same temperature for 2 hours to complete the polymerization. . In addition, when the monomer was continuously added over 1 hour, 0.2 weight part sodium N-lauroyl sarcosinate was added. The obtained latex of the innermost layer polymer (A1a) was a cross-linked methacrylic polymer latex, the number average particle size of the polymer particles therein was 160 nm, and the polymerization conversion rate was 98%. However, the number average particle diameter of the innermost polymer particles in A1-8 was 135 nm.

  In order to polymerize the rubber copolymer (A1c), the latex of the innermost layer polymer (A1a) obtained above was kept at 80 ° C. in a nitrogen stream, and 0.1 parts by weight of potassium persulfate was added thereto. After that, the monomer for rubber copolymer shown in Table 2 was continuously added over 5 hours. During this 5 hours, 0.1 part by weight of potassium oleate was added in three portions. After completion of the addition, 0.05 part by weight of potassium persulfate was further added to complete the polymerization, and the mixture was held for 2 hours, whereby the rubber-containing acrylic graft copolymer A1-5 to A1-8 having a three-layer structure was added. A latex of polymer particles having a two-layer structure consisting of an innermost layer polymer (A1a) and a rubber copolymer (A1c) was obtained. The number average particle diameters of the polymer particles having up to the obtained two-layer structure were the values shown in Table 2, respectively, and the polymerization conversion rate was 99% in common.

  In order to polymerize the graft component (A1s), the latex latex of the polymer particles having the two-layer structure obtained above was kept at 80 ° C., and 0.02 part by weight of potassium persulfate was added thereto, Graft composition shown in Fig. 2, that is, MMA, BA and MA which are monomers for graft components, and n-DM which is a polymerization initiator are mixed in a polymerization part shown in Table 2 over 2 hours. Added continuously. By holding for 1 hour after the addition of the mixture was completed, latex of a rubber-containing acrylic graft copolymer A1-5 to A1-8 having a three-layer structure was obtained. The polymerization conversion rate was 99% in common. The resulting rubber-containing acrylic graft copolymer A1-5 to A1-8 having a three-layer structure is subjected to salting-out coagulation, heat treatment and drying by a known method to obtain a white powder. A1-5 to A1-8 were obtained.

(Manufacture of carbon black masterbatch)
In order to improve the dispersibility of carbon black, 40 parts by weight of carbon black (Mitsubishi Chemical # 2600) having an average primary particle of 13 nm, acrylic plasticizer resin (methyl methacrylate 87% by weight, and methyl acrylate 13 60% by weight of a copolymer consisting of 15% by weight and having a melt flow (JIS K7210, 230 ° C. * 37.3N) of 15) and 0.5 parts by weight of an antioxidant (Irganox 1010 manufactured by Ciba Japan) Was then pelletized twice at 240 ° C. using a 44 mm twin screw extruder and then pulverized to produce a carbon black masterbatch (CB-1).

  For comparison, carbon black master batch (CB-2) was produced in the same manner using carbon black (Mitsubishi Chemical # 20) having an average primary particle size of 50 nm.

(Examples and comparative examples)
The following resins were used as the acrylic resin (A2).
A2-1: A copolymer of acrylic resin monomers comprising 97% by weight of methyl methacrylate and 3% by weight of methyl acrylate, with a melt flow (JIS K7210, 230 ° C. * 37.3N) of 2.0. thing.
A2-2: A copolymer of monomers for acrylic resin consisting of 87% by weight of methyl methacrylate and 13% by weight of methyl acrylate, having a melt flow (JIS K7210, 230 ° C. * 37.3N) of 15.

  A rubber-modified acrylic resin (A) composed of a rubber-containing acrylic graft copolymer (A1) and an acrylic resin (A2) and a carbon black masterbatch are blended in the parts by weight shown in Table 3, and further absorbs ultraviolet rays. 0.5 parts by weight of benzotriazole UV absorber “Tinuvin 234” (registered trademark) manufactured by Ciba Japan, which is an agent, hindered amine light stabilizer “ADK STAB LA-63” manufactured by Asahi Denka Kogyo Co., Ltd. (Registered Trademark) 0.5 parts by weight, and a blend of 0.5 parts by weight of hindered phenolic antioxidant “Irganox 1010” (registered trademark) manufactured by Ciba Japan, which is an antioxidant, Using a twin screw extruder, it was pelletized at 240 ° C., and a flat plate and a bar of 150 * 150 * 3 mm were formed using the pellet. In Comparative Example 4, a carbon black masterbatch was not used, and instead, a nigrosine dye (Nigrosine Base EX manufactured by Orient Chemical Industry Co., Ltd.) was added as it was without making it a masterbatch.

  Using the bar sample thus obtained, an Izod impact test was conducted under the conditions of ¼ inch, no notch, and 23 ° C. in accordance with ASTM D-256. Table 3 shows the measurement results.

  Moreover, the jetness was visually evaluated using the flat plate sample. The evaluation results are shown in Table 3 as ◎: very good, ◯: excellent, X: inferior (blur black).

  Further, in the same manner except that no carbon black masterbatch was blended, the total light transmittance was measured by the method shown in JIS K 7361-1, using a sample obtained by molding a flat plate of 150 * 150 * 3 mm. Transparency was evaluated by the value of the average transmittance at a wavelength of 380 to 780 nm of the thick molded body.

  Evaluation of weather resistance was performed by cutting a 150 * 150 * 3 mm flat plate sample into 47 * 72 * 3 mm, and making it a WEL-SUN-HCH / B type sunshine carbon arc lamp type weather resistance tester manufactured by Suga Test Instruments Co., Ltd. (Sunshine Super Long Life Weatherometer) was used to conduct a weather resistance test for 2000 hours under conditions of a black panel temperature of 63 ° C. and a water spray cycle of 12 minutes during 60 minutes of irradiation. The jetness was carried out by visual evaluation in the same way as the initial jetness evaluation method.

  The water resistance was evaluated by conducting a water resistance test in which the 150 * 150 * 3 mm flat plate sample was cut into 47 * 72 * 3 mm and immersed in pure water at 80 ° C. for 100 hours. The jetness was carried out by visual evaluation in the same way as the initial jetness evaluation method.

  Table 3 shows the compositions and evaluation results of the above Examples and Comparative Examples.

  As shown in Table 3, the rubber-modified acrylic resin composition of the present invention is excellent in jetness, impact resistance, weather resistance, and moisture resistance.

(Measurement)
Total light transmittance Nippon Denshoku NDH-300A JIS K-7105
Color difference meter Nippon Denshoku SE2000 JISZ8722 0-45 degrees Post-spectral method Reflection mode, 2 times average, aperture attachment φ30

(Weather resistance test)
In accordance with JIS K 7350-4, the test was conducted at a black panel of 63 ° C., with rain, and an irradiation energy of 255 W / m ² .

(Resin used)
Acrylic resin 1 Mitsubishi Rayon Acrypet VH001 (Catalog value: deflection temperature under load (JISK 7191, 1.80 MPa) 100 ° C., melt flow rate (JIS K 7210, 230 ° C., 37.3 N) 2.0 g / 10 min)
Acrylic resin 2 Kuraray Parapet F1000
Acrylic resin 3 Asahi Kasei Delpet 80NE (Catalog value: deflection temperature under load (ISO75-1, 75-2) 97 ° C., melt flow rate (ISO1133 cond13) 2.3 g / 10 min)
Acrylic resin 4 720V (catalog value: deflection temperature under load (ISO75-1, 75-2) 93 ° C., melt flow rate (ISO1133 cond13) 21 g / 10 min)
Acrylic rubber 1 Made by Kaneka Co., Ltd. Acrylic modifier Kane Ace M210 (Rubber particles with multi-layer structure, core: acrylic rubber with multi-layer structure, shell: acrylic polymer based on methyl methacrylate, approximate particle size: 220 nm )

(Carbon black)
Carbon black having an average primary particle size of 13 nm: 40 parts by weight, acrylic resin 2: 59 parts by weight, antioxidant (Irganox 1010): 0.5 parts by weight, dispersant (alkyl acid ester): 0.5 parts by weight The carbon black masterbatch (CB-3) was manufactured by pulverizing the part twice using a 44 mm twin screw extruder at 260 ° C.

  As a comparative example, Sumika Color, SPAB-8K500 (carbon concentration 45%) was used.

(Other ingredients)
In addition to being listed in the recipe, Ciba Japan, Tinuvin 234 (benzotriazole UV absorber). Asahi Denka Kogyo Co., Ltd., ADK STAB LA-63 (hindered amine light stabilizer). Ciba Japan and Irganox 1010 (hindered phenol antioxidant) were used in an amount of 0.5 parts by weight, respectively.

(Single screw extrusion)
Using a 40 mm single-screw extruder, the die head temperature was set to 260 ° C., and the dry blended resin material and the like were extruded to form pellets with a pelletizer.

(Twin screw extrusion)
Using a 44 mm twin screw extruder JSW-TEX44, the die head temperature was set to 260 ° C. and pelletized in the same manner.

(injection molding)
Using a FANUC auto-shot FAS-150B (clamping force 150 tons) injection molding machine, the nozzle tip temperature was set to 250 ° C., and a 150 × 150 * 3 mm flat plate (mirror finish) was molded.
Using a Toshiba IS-75E (clamping force 75 tons) injection molding machine, the nozzle tip temperature was set to 250 ° C., and ASTM standard bar dumbbells were molded.
Using a Nissei Plastic Industries FN-1000 (clamping force 80 tons) injection molding machine, the nozzle tip temperature was set to 250 ° C., and a 50 × 80 * 2 mm color plate (mirror finish) was molded.

(Evaluation)
Using the bar sample, an Izod impact test was carried out under the conditions of ¼ inch, notched, and 23 ° C. according to ASTM D-256. Unit: J / m
Using the bar sample, the HDT test was performed under the condition of 0.45 MPa in accordance with ASTM D648. Unit: ° C
Using the pellets before molding, an MFR test was performed under the conditions of 230 ° C. and 5 kgf in accordance with ASTM D1238. Unit: g / 10min
The jetness was visually evaluated using a flat plate sample. The evaluation results are shown as ◎: very good, ◯: excellent, X: inferior (blur black).
The Lab value was measured with a color difference meter SE2000 (Nippon Denshoku Industries Co., Ltd.) using the mirror surface of the flat plate and the color plate molding.
The result of each Example and comparative example which performed the mixing | blending, extrusion by a single screw extruder, shaping | molding, and evaluation according to the composition shown in Table 4 is shown. However, Comparative Example 7 was measured by removing a C pillar (black mirror surface) which is an exterior part of Nissan Murano. In addition, Examples 16, 17, 18, and Comparative Example 6 in Table 4 contain 2,2′-methylenebis (4,6-di-tert-butylphenyl) octyl phosphite as a phosphorus stabilizer. 0.3 parts by weight was blended.

  In comparison with a flat plate, as shown in Examples 10 to 18 of Table 4, the rubber-modified acrylic resin composition of the present invention has an L value in the range of about 5.0 to about 6.0, and is a comparative example. Since L value shown by 5-6: about 8.2 to about 8.8 is significantly low, it can be said that the composition and molded object of this invention have high jetness.

  Similarly, in the comparison of the color plates, the L values of Examples 10 to 18 in Table 4 are in the range of about 5.7 to about 6.5, and the L values shown in Comparative Examples 5 to 6 are about 9.4. Since the value is significantly lower than about 9.9, it can be said that the composition and the molded body of the present invention have high jetness. It seems that the L value of the color plate is generally higher than that of the flat plate due to the resin orientation of the surface.

  In any case, the L value of this example is lower than the L value of Comparative Example 7: about 7.7, and it can be said that the jetness is high.

  As described above, in the examples, although the initial L value is low, the change in the L value before and after the weather resistance test 1000 h is within 1, so the material of the present invention has a jetness. It can be seen that the weather resistance is also excellent.

  The result of each Example and comparative example which performed the mixing | blending, extrusion by a twin-screw extruder, shaping | molding, and evaluation according to the composition shown in Table 5 is shown. In Comparative Example 8, A pillar (black mirror surface) which is an exterior part of a mini cooper manufactured by BMW Group was removed and measured. In addition, when a small amount of material scraped off from the A pillar was taken and immersed in methanol, red to purple color components were extracted, and thus it was found that the pillar was colored with a dye. The IR spectrum of this methanol-soluble component was in good agreement with the IR spectrum of the anthraquinone dye. In addition, the IR spectrum measured by dissolving this small amount of material scraped with THF and casting this soluble component on a KBr plate was in good agreement with the IR spectrum of the PMMA resin. Furthermore, when TEM observation of this material was performed, rubber particles, such as an acrylic rubber component, were not seen.

  In the flat plate, as shown in Examples 19 to 23 of Table 5, the rubber-modified acrylic resin composition of the present invention has an L value in the range of about 5.2 to about 5.8, and in the color plate. The L value is in the range of about 5.9 to about 7.3, and even if the melt kneading method is different, it can be said that the composition and the molded body of the present invention have high jetness.

  As described above, even in these examples, although the initial L value is low, the change in the L value before and after the weather resistance test 1000 h is within 1, so the material of the present invention is It can be seen that weatherability is excellent as well as jetness. On the other hand, in Comparative Example 8, although the initial L value is low, the change in the L value before and after the weather resistance test 1000 h exceeds 1, indicating that the weather resistance is poor.

Claims (6)

A resin obtained by blending 0.05 to 10 parts by weight of carbon black (B) with 100 parts by weight of a rubber-modified acrylic resin (A) having a transparency with a total light transmittance of 85% or more of a molded product having a thickness of 3 mm. A composition comprising:
100 parts by weight of the rubber-modified acrylic resin (A)
Rubber containing acrylic graft copolymer (A1) 5 to 100 parts by weight, and acrylic resin (A2) 95 to 0 parts by weight,
The rubber-containing acrylic graft copolymer (A1) has an inner layer of the rubber copolymer (A1c) and an outer layer of the graft component (A1s) covering the inner layer, and the weight ratio of A1c: A1s is 5:95 to 85. : A multilayer structure graft copolymer comprising 15;
The rubber copolymer (A1c) is an acrylic acid alkyl ester of 50 to 99.9% by weight, another copolymerizable vinyl monomer of 0 to 49.9% by weight, and a polyfunctional monomer of 0.1%. A polymer of 100% by weight of a monomer for rubber copolymer consisting of 10% by weight,
The graft component (A1s) is composed of 50 to 100% by weight of a methacrylic acid alkyl ester and 100% by weight of a monomer for a graft component consisting of 0 to 50% by weight of a vinyl monomer other than the copolymerizable alkyl methacrylate. A polymer, and
The acrylic resin (A2) is a polymer of acrylic resin monomers consisting of 0 to 50% by weight of an acrylic acid alkyl ester and 100 to 50% by weight of an alkyl methacrylate.
A jet black rubber-modified acrylic resin composition, wherein the carbon black dispersed in the resin composition has a particle size of 10 to 40 nm. The rubber-modified acrylic resin composition according to claim 1 , wherein the rubber-containing acrylic graft copolymer (A1) has a number average particle diameter of 30 to 400 nm. The rubber-containing acrylic graft copolymer (A1) further includes the innermost layer polymer (A1a) at a weight ratio of A1a: (total amount of A1c and A1s) of 10:90 to 40:60, And,
A multilayered graft copolymer having at least a three-layer structure obtained by polymerizing the rubber copolymer monomer in the presence of the innermost layer polymer (A1a); and
The innermost layer polymer (A1a) is one or more selected from the group consisting of methacrylic acid alkyl ester and aromatic vinyl and 40 to 99.9% by weight, and other vinyl monomers copolymerizable 59.9. The rubber modification according to claim 1 or 2 , which is a polymer of 100% by weight of an innermost layer polymer monomer consisting of ˜0% by weight and 0.1 to 5% by weight of a polyfunctional monomer. Acrylic resin composition. The molded object formed by shape | molding the resin composition in any one of Claims 1-3 . The molded article according to claim 4 , wherein a flat molded article injection-molded with a mirror-finished mold is measured with a 0-45 degree spectroscopic color difference meter defined in JISZ-8722. A molded product having an L value in the range of 0 to 8. 6. The molded product according to claim 5 , wherein a flat molded product obtained by injection molding with a mirror-finished mold is subjected to black panel 63 ° C., rain, 255 W / m ² as defined in JIS K 7350-4. A molded article, wherein a weather resistance test is performed for 1000 hours, and a change in L value in a color difference meter before and after the test is in a range of 0 to 1.