JPH086005B2 - Acrylic resin composition having excellent matting properties for molded articles, molded article and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an acrylic resin composition having excellent matte properties,
Regarding the molded article and the method for producing the same, more specifically, an acrylic resin composition for an injection molded article having excellent matte properties, an acrylic resin molded article having an excellent matte surface formed by injection molding the composition, and The present invention relates to a method for producing the molded article.

(Prior Art) Methyl methacrylate polymer has many applications such as nameplates, instrument covers, displays, and lighting covers as plate-shaped or uneven products, and recently has a matte surface in order to enhance high-class feeling and antiglare effect. The use as an acrylic resin molded product has become extremely popular. Conventionally, in order to obtain an acrylic resin molded product having a matte surface, fine irregularities are provided on the mold surface such as extrusion molding rolls, casting molding, compression molding, and injection molding to make it matte or to use inorganic fine powder. It is common practice to knead and extrude, or to apply a matte coating to a molded product after molding.

(Problems to be Solved by the Invention) However, in the case where the surface of a molding die such as a conventional molding roll or a mold is provided with fine irregularities to provide a matte surface, the surface of the molding die depends on the degree of the matte surface. When it is difficult to maintain a uniform matte state over a wide area, and when secondary heat processing such as press processing and vacuum processing is required, such as for lighting cover applications, etc. There was a problem to be solved that the fine irregularities on the surface disappear and the matte effect disappears. As a technique for improving the disappearance of such a matte surface by thermoforming, there is a matte plate in which inorganic fine powder is blended, kneaded and extruded (JP-A-53-147748).
In order to obtain a uniform and sufficient matte state, a large amount of inorganic fine powder is required. As a result, the total light transmittance and parallel light transmittance become small, so that a matte state with good translucency can be obtained. It had the drawback of not having it. Also, in the case of matte coating, a coating process is required separately from the molding process,
It has a problem that it cannot be applied uniformly over a wide area and difficult to apply area.

The present invention has been made by paying attention to such problems to be solved in the related art, and in the injection molding method which is excellent in mass productivity and does not need to be subjected to secondary heat processing, the surface of the molding die is processed into a matte surface. It is an object of the present invention to obtain an acrylic resin molded article having a matte surface excellent in antiglare property, solvent resistance and mechanical strength, without performing.

(Means for Solving the Problems) The inventors of the present invention have made earnest studies in an injection molding method that is excellent in mass productivity and does not need to be subjected to secondary heat processing, and as a result, polymer fine particles having a specific particle diameter have been made into acrylic particles. It has been found that the above problems can be solved by blending with a resin, and the present invention has been completed.

That is, according to the present invention, these objects, 100 parts by weight of methyl methacrylate polymer is a copolymer or homopolymer containing 80% or more methyl methacrylate,
0.5 to 15 parts by weight of crosslinked methacrylic acid ester polymer fine particles and / or high degree of polymerization methacrylic acid ester polymer fine particles having an average particle size in the range of 4 to 15 μm and a particle size of less than 10 μm occupying 65% or more by weight distribution. This is achieved by the acrylic resin composition for injection-molded articles, which is excellent in mattness and is contained.

Further, the above-mentioned object is achieved by an acrylic resin molded article having excellent matting properties, which is obtained by injection molding the above acrylic resin composition.

Furthermore, the above-mentioned object is a method for obtaining an acrylic resin molded article by injection-molding an acrylic resin material, in which the acrylic resin composition is injection-molded into a mold cavity that has not been subjected to a matting process. This is achieved by an excellent method for producing an acrylic resin molded product.

(Operation) In the present invention, the methyl methacrylate polymer means a copolymer or homopolymer containing 80% or more of methyl methacrylate, and contains a trace amount of additives such as an ultraviolet absorber, a heat stabilizer, a colorant, and a filler. There is no problem in going out. The molecular weight is not particularly limited in the present invention, but is generally 50,000 to 500,000, preferably 70,000 to 300,000 in view of easiness of kneading at the time of injection molding, physical properties and the like. is there.

The crosslinked methacrylic acid ester polymer fine particles and / or high degree of polymerization methacrylic acid ester polymer fine particles used in the present invention means a monomer which is copolymerizable with a methacrylic acid ester or a methacrylic acid ester containing methacrylic acid ester as a main monomer component. Fine powder obtained by subjecting a mixture of a monomer and a cross-linking agent to bulk polymerization and casting polymerization to mechanically pulverized fine powder or suspension polymerization, methacrylic acid ester or methacrylic acid ester containing methacrylic acid ester as a main monomer component. Polymerization of a monomer mixture copolymerizable with 5,000 or more, preferably 8000 or more bulk polymerization, fine particles obtained by mechanically pulverizing a product obtained by casting polymerization or fine particles obtained by suspension polymerization,
Alternatively, it means fine particles obtained by mixing these.

As the methacrylic acid ester used in the present invention,
Examples include straight-chain aliphatic esters such as methyl methacrylate, octyl methacrylate and stearyl methacrylate, branched aliphatic esters such as tert-butyl methacrylate and 2-ethylhexyl methacrylate, unsaturated esters such as allyl methacrylate and the like. Preferred are straight chain aliphatic esters such as ethyl acid and stearyl methacrylate.
Most preferred is methyl methacrylate. Examples of the monomer copolymerizable with methacrylic acid ester include (meth) acrylic acid alkyl esters other than methacrylic acid ester as the main component (((meth) acrylic acid alkyl ester is acrylic acid alkyl ester, and methacrylic acid alkyl ester. Acid alkyl ester, the same applies hereinafter), (meth)
Acrylic acid hydroxyalkyl ester, (meth) acrylic acid, (meth) acrylonitrile, styrene, α-methylstyrene, maleic anhydride, and the like. The cross-linking agent is not particularly limited, but it is preferable to use a cross-linking agent having two or more unsaturated groups. For example, a difunctional difunctional diethylene diethylene methacrylate, polyethylene glycol dimethacrylate, neopentyl glycol dimethacrylate or the like. Methacrylate, divinylbenzene and the like can be preferably used, and are used in an amount of 1 to 50% by weight, preferably 5 to 50% by weight, based on all monomers. As the fine particles obtained by suspension polymerization, there is disclosed in Japanese Patent Laid-Open No. 48838/1988.
Manufactured by Matsumoto Yushi-Seiyaku Co., Ltd .: Matsumoto Microspheres M305 (crosslinked polymethylmethacrylate spheres) manufactured by the formulation and suspension method disclosed in Japanese Patent Application No. 62-307238 Microparticles), Sekisui Plastics Co., Ltd .: Techpolymer MB (polymethylmethacrylate microspherical microparticles: high degree of polymerization type), MBX (crosslinked polymethylmethacrylate microspherical microparticles) and the like can be used. The fine particles used in the present invention have an average particle diameter of 4 to 15 μm and a particle diameter of 10 μm.
Particles having a particle size of less than m account for 65% or more in the weight distribution, and as a more preferable embodiment of the fine particle, the particle diameter is from the viewpoint of the stability of the matte appearance and the uniformity of the matte surface with respect to the fluctuation of the polymer particle content. 1-30 μm, preferably 1-
Particles in the range of 20 μm and with a particle size of less than 10 μm have a weight distribution
It occupies 70% or more, preferably 90% or more. The average particle size referred to here is the total weight obtained by integrating the particle sizes by weight.
A particle size corresponding to 50% is meant, for example, a permeation type particle size distribution measuring instrument by gravity sedimentation method (manufactured by Seishin Enterprise Co., Ltd .: SKA500).
0) and the like. Spherical fine particles produced by suspension polymerization are preferably used in terms of uniformity of matte state and texture, and narrow particle size distribution is more preferably used because uniform matteness can be obtained. The average particle size of the polymer particles is
If it exceeds 15 μm, the surface is not fine and uniform, and it is not preferable. Further, the amount thereof is different depending on the intended use, but is 0 for obtaining good antiglare property.
It is necessary to add 5 to 15 parts by weight, preferably 2 to 10 parts by weight, per 100 parts by weight of the methyl methacrylate polymer. If it is less than 0.5 parts by weight, the matte state of the surface is not sufficient and the glossiness rises and the beauty is lost, while if it exceeds 15 parts, the matte state of the surface is uniform, It does not have a favorable effect on performance. Further, when the fine particles are not a cross-linking system and the degree of polymerization is less than 5000, the fine particles are not dissolved in the base resin during kneading in injection molding and a matte state is not exhibited, or it is extremely insufficient, which is not preferable. .

The acrylic resin composition for injection molding having excellent matting property in the present invention means the methyl methacrylate polymer 10
The crosslinked methacrylic acid ester polymer fine particles and / or the high degree of polymerization methacrylic acid ester having an average particle size in the range of 4 to 15 μm and particles having a particle size of less than 10 μm occupy 65% or more in weight distribution with respect to 0 part by weight. 0.5 polymer particles
It is contained in an amount of up to 15 parts by weight, and means, for example, a mixture of the methyl methacrylate polymer and the fine particles with stirring using a Hensyl mixer or the like, or a mixture which is pelletized by an extruder after mixing. The composition is preferably used in the form of pellets for stable storage or for better feeding into the molding machine. The composition of the present invention is used as an injection molding material, but in extrusion molding, the matte state is easily influenced by the contact state with the molding roll after the resin is extruded, so that the effect cannot be sufficiently exhibited.

The injection molding conditions in the present invention are not essential constitutional requirements of the present invention, and the acrylic resin composition is applied to a mold cavity that has not been subjected to a matting process under normal injection conditions using a normal injection molding machine. By injection molding, it is possible to produce an acrylic resin molded article having excellent matting properties. For example, the above-mentioned methyl methacrylate polymer and the above-mentioned fine particles are mixed by stirring with a Hensyl mixer or the like, or they are subjected to an extrusion molding machine after mixing. An acrylic resin molded product having a uniform matte surface can be obtained by injection molding the pelletized product into the mirror surface mold cavity with an injection molding machine.

The acrylic resin molded article of the present invention obtained as described above exhibits a matte surface having good mechanical strength and solvent resistance and excellent antiglare property, but the refraction of the base resin and polymer fine particles When the ratios are almost equal, it can be easily made transparent by polishing a predetermined surface portion after molding, which is also advantageous when a molded product having a partially transparent portion is manufactured.

(Examples) Hereinafter, the present invention will be described more specifically with reference to Examples.

Incidentally, "%" and "parts" in Examples and Comparative Examples all represent "% by weight" and "parts by weight", respectively,
The performance of the acrylic resin molded articles obtained in the examples and comparative examples was measured and evaluated by the following methods.

Surface condition A fluorescent lamp was reflected on the sample in the room and visually observed, and the matte state of the sample was represented by the following symbol.

○: The outline of the fluorescent lamp is not recognized or is hardly recognized.

B: The outline of the fluorescent lamp is recognized, but it is unclear, and the surface has irregularities.

X: The outline of the fluorescent lamp was clearly recognized, and there were almost no surface irregularities.

Light transmittance measurement In accordance with JIS K7105, integrating sphere type light transmittance measuring device (Murakami Color Research Laboratory: Light transmittance / reflectance meter RM-1)
5), and the total light transmittance, parallel light transmittance and haze value were calculated.

Gloss level 60 ° -60 ° by gloss meter (Suga Test Instruments Co., Ltd .: SM color computer) according to JIS K7105 gloss measurement
It was measured by reflection.

Surface roughness In accordance with JIS B0601, surface roughness meter (Kosaka Laboratory Ltd .:
Ten-point average roughness (Rz) by universal surface profilometer SE-3C)
Was measured.

Example 1 A 5 l separable flask was charged with a polymerization degree as a suspension dispersant.
2120, saponification degree 79.4% of polyvinyl alcohol (Kuraray Co., Ltd. PTA420) 18.37 g is dissolved in 2625 ml of distilled water, as a monomer system stearyl methacrylate 300 ml, ethylene glycol dimethacrylate 300 ml, toluene 400 ml,
A solution of 1,200 g lauroyl peroxide was added. This mixed solution is a lab disperser (X-manufactured by Mitamura Riken Co., Ltd.).
1020 type) with the largest particle size observed under the microscope.
It was dispersed until it became 20 μm. A thermometer, a stirrer, and a cooling tube were attached to the flask, and the polymerization reaction was carried out at 80 ° C. for 6 hours under a nitrogen stream. The obtained slurry was suctioned, and the separated fine particles were dispersed again in distilled water to wash the attached polyvinyl alcohol. 2 at 100 ℃
It was dried under vacuum for a day to evaporate the diluent toluene and observed with an optical microscope. The particle size was 2 to 20 μm and the average particle size was 7 μm.
m (particles of less than 10 μm have a weight distribution of 84% or more) crosslinked polymethylmethacrylate fine particles were obtained.

To 100 parts of a methyl methacrylate polymer containing 5% of methyl acrylate, 0.1 part, 1 part, 2 parts, 5 parts, and 10 parts of the crosslinked polymethylmethacrylate fine particles were added, respectively, and mixed and stirred with a Hensyl mixer. After that, each is extruded with an extruder (VSK-40, manufactured by Chuo Kikai Seisakusho), pelletized, and molded with an injection molding machine (IS-25EP, manufactured by Toshiba Machine Co., Ltd.) equipped with a mold having a cavity with a mirror surface. Molding was performed under conditions of a temperature of 200 to 240 ° C and a mold temperature of 50 ° C to obtain a flat plate molded product having a thickness of 2 mm.

The performance evaluation results of these molded products are shown in Table 1.
Except for 1 part fine particles, fine and uniform matte surface was obtained.

Example 2 100 parts of methyl methacrylate polymer containing 5% of methyl acrylate and having a degree of polymerization of 9300 and a particle size distribution of 1 to 24 μm and an average particle size of 7 μm (particles less than 10 μm have a weight distribution of 82%). 1 part, 2 parts, 5 parts, 10 parts, 15 parts and 20 parts of high degree of polymerization polymethylmethacrylate fine particles (manufactured by Sekisui Plastics Co., Ltd .: Technopolymer MB-8, true specific gravity 1.19) are added respectively. After mixing and stirring with a Hensil mixer, each was pelletized with an extruder, and the pellets were injection molded in the same manner as in Example 1 to obtain a flat plate molded product having a thickness of 2 mm. The performance evaluation results of these molded products are shown in Table 1. All of them had fine and uniform matte surface.

Example 3 100 parts of methyl methacrylate polymer containing 5% of methyl acrylate, having a particle size distribution of 2 to 40 μm and an average particle size of 11 μm (particles less than 10 μm have a weight distribution of 65%).
1 part of 5 crosslinked polymethylmethacrylate fine particles (manufactured by Matsumoto Yushi-Seiyaku Co., Ltd .: Microsphere M-305)
Parts, 10 parts, 15 parts, 20 parts, respectively, and after mixing and stirring with a Hensyl mixer, pelletized with an extruder, and the pellets were injection molded in the same manner as in Example 1 to obtain a flat plate molded product having a thickness of 2 mm. It was The performance evaluation of these molded products is shown in Table 1. All of them had fine and uniform matte surface.

Example 4 The monomer system was 30% methyl methacrylate, 50% ethylene glycol, 3% methyl acrylate and 16% styrene, and the average particle size was 6 to 26 μm in the same manner as in Example 1 except that no diluent was used. A crosslinked polymer fine particle having a particle diameter of 10 μm (70% of particles less than 10 μm in weight distribution) was obtained, and 0.1 part, 1 part of the above fine particle was added to 100 parts of a methyl methacrylate polymer containing 5% of methyl acrylate. After adding 5 parts, 10 parts, and 15 parts, respectively, mixing and stirring with a Hensyl mixer, pelletizing with an extruder, injection molding was carried out in the same manner as in Example 1 to obtain a flat plate molded product having a thickness of 2 mm. The performance evaluation of these molded products is shown in Table 1. The molded products in which 1 part or more of the fine particles were blended had a matt performance and a translucent milky white color.

Example 5 Example 4 except that the monomer system was 80% methyl methacrylate and 20% neopentyl glycol dimethacrylate.
In the same way as above, the particle size is 2-30 μm and the average particle size is 10 μm
Crosslinked polymethylmethacrylate fine particles having a particle size distribution of less than 10 μm (70% by weight distribution) were obtained, and 1 part, 5 parts, 10 parts of the above fine particles were added to 100 parts of methyl methacrylate polymer containing 5% of methyl acrylate. Each part was added and mixed and stirred with a Hensyl mixer, and then pelletized with an extruder to obtain a flat plate molded product having a thickness of 2 mm in the same manner as in Example 1. The evaluation results of the appearance, light transmittance and glossiness of these molded products showed the same results as the performance evaluation corresponding to the same amount of added fine particles in Example 3.

Example 6 To 100 parts of a pellet-shaped methyl methacrylate polymer containing 5% of methyl acrylate, 2 parts of fine particles obtained by mixing the fine particles of Example 2 and the fine particles of Example 3 in a ratio of 1: 1 were added. After mixing and stirring with a sill mixer, the mixture was pelletized with an extruder to obtain a flat plate molded product having a thickness of 2 mm in the same manner as in Example 1. This molded product had a fine and uniform matte surface and had a total light transmittance of 90%, a parallel light transmittance of 87%, a haze value of 4%, and a glossiness of 112.

Comparative Example 1 1 part of crosslinked polymethylmethacrylate fine particles (Sekisui Plastics Co., Ltd .: Techpolymer MBX-100) having an average particle size of 100 μm was used with respect to 100 parts of a methyl methacrylate polymer containing 5% of methyl acrylate. 2 parts, 5 parts, 10 parts, and 20 parts were added, mixed and stirred with a Hensyl mixer, pelletized with an extruder, and molded in the same manner as in Example 1 to obtain a flat plate molded product having a thickness of 2 mm. It was The results of performance evaluation of these molded products are shown in Table 1, but the surface did not have a uniform matte surface, but showed a cod-like surface in which particles were aggregated.

Comparative Example 2 100 parts of a methyl methacrylate polymer containing 5% of methyl acrylate was used, and a high degree of polymerization polymethylmethacrylate fine particle having an average particle size of 110 μm and having a main particle size distribution at a degree of polymerization of 11,100, 70 to 15 μm (Mitsubishi Rayon Co., Ltd .: Acrycon) was added in an amount of 1 part, 3 parts, and 10 parts, respectively, mixed and stirred with a Hensyl mixer, pelletized with an extruder, and molded in the same manner as in Example 1 to have a thickness of 2 mm. A flat plate molded product was obtained. The performance evaluation results of these molded products are shown in Table 1, and the surface condition was the same as that of Comparative Example 1.

Comparative Examples 3 and 4 Inorganic fine powder was used in place of the polymer fine particles, and Example 1 was used.
Table 1 shows the performance evaluation results of the molded products obtained by injection-molding after mixing and stirring in the same manner as above, pelletizing. As the inorganic powder, silica was used in Comparative Example 3 (Aerosil R-972, Aerosil Co., Ltd. in Japan), and barium sulfate (precipitable barium sulfate, manufactured by Sakai Chemical Co., Ltd.) was used in Comparative Example 4.

It is necessary to increase the amount of the inorganic powder blended in order to achieve a matte state, but in this case the translucency is reduced and the mechanical strength is much larger than that of the polymer fine particle blended. Fell to.

Comparative Example 5 Table 1 shows the performance of the commercially available mold transfer sheet. Commercial product A
Is an example of a matte and light product, and the commercial product B is an example of a matte and tight product.

Example 7 With respect to 100 parts of a methyl methacrylate polymer containing 5% of methyl acrylate, a polymerization degree of 9000 and a particle size distribution of 1 to 20 μm and an average particle diameter of 4.5 μm (particles less than 10 μm are 95% by weight distribution). %) Of high degree of polymerization polymethylmethacrylate fine particles and titanium oxide (R-680 manufactured by Ishihara Sangyo Co., Ltd.) 1
Each part was added and mixed and stirred with a Hensyl mixer in the same manner as in Example 1, pelletized with an extruder, and the pellets were injection-molded to obtain a flat plate molded product having a thickness of 2 mm. The results of performance evaluation of these molded products are shown in Table 2. In the case of this example, the glossiness changes greatly depending on the addition amount of fine particles, but the surface roughness hardly changes and the surface unevenness is Another unique feature was found that was the same.

Example 8 High degree of polymerization polymethylmethacrylate fine particles having a degree of polymerization of 8500 and a particle size distribution of 2 to 25 μm and an average particle diameter of 8 μm (73% of particles less than 10 have 73% by weight distribution) and calcium carbonate (Nemoto Special Chemical Co., Ltd.) Manufactured: DNF-7) A flat plate molded product having a thickness of 2 mm was obtained in the same manner as in Example 7 except that 0.8 part was used, and the performance evaluation results of these molded products are shown in Table 2.

Example 9 A flat plate molded product having a thickness of 2 mm was obtained in the same manner as in Example 8 except that 0.35 part of the black dye / pigment was used instead of calcium carbonate, and the performance evaluation results of these molded products are shown in Table 2. Indicated.

Example 10 and Comparative Example 6 The mechanical strengths of the molded products containing the polymer fine particles of Examples 2 and 3 and the molded product containing the inorganic powder of Comparative Example 3 were measured as AS.
It was measured according to TMD638 and D256. The results are shown in the table below, and it can be seen that the one containing the polymer fine particles is superior in mechanical strength to the one containing the inorganic powder.

Example 11, Comparative Example 7 For the purpose of evaluating the solvent resistance to brake oil and isopropyl alcohol, a cantilever beam was prepared using a dumbbell-shaped molded article containing polymer fine particles and a dumbbell molded article containing no fine particles having the composition of Example 3. Supports dumbbells with a load of 500 g,
The rupture time of the dumbbell was measured under the condition of the fulcrum stress of 271 kg / cm ² . The results are shown in the table below. It can be seen that the one containing the polymer fine particles has a longer breaking time and the solvent resistance is improved as compared with the one containing no polymer particles.

(Effect) As described above, the present invention uses methyl methacrylate.
Cross-linked methacryl having an average particle size in the range of 4 to 15 μm and particles having a particle size of less than 10 μm occupy 65% or more with respect to 100 parts by weight of a methyl methacrylate polymer which is a copolymer or homopolymer containing 80% or more. Since it is an acrylic resin composition for injection molded articles, which is excellent in mattness and contains 0.5 to 15 parts by weight of acid ester polymer particles and / or high polymerization degree methacrylic acid ester polymer particles,
Since the matte state can be changed depending on the particle size and the addition amount of the polymer fine particles to be blended, it is possible to simply provide a composition for molded articles having various matte states. Particularly, it is useful as an injection molding material having excellent mass productivity.

In addition, since it is an acrylic resin molded product excellent in matting property obtained by injection-molding the above-mentioned acrylic resin composition for molded products excellent in matting property, it is an injection molded product that does not need to be subjected to secondary heat processing. Since it is available, it can be supplied in large quantities at low cost,
Since it is a molded article having a matte surface excellent in solvent resistance and mechanical strength, it is useful as a lighting cover, display, glazing or instrument cover having various matte surfaces. In particular, when a transparent acrylic resin is used as the base resin, it is excellent in light-transmitting property and is useful as a highly energy-saving molded product, and when the base resin and the polymer fine particles have almost the same refractive index. Since it can be easily made transparent by polishing predetermined front and back portions after molding, it is useful because a molded product having a partially transparent portion can be produced.

Furthermore, the present invention is a method for producing an acrylic resin molded article having excellent matting properties by injection-molding the above acrylic resin composition into a mold cavity that has not been subjected to matting processing. As a result, it is possible to manufacture a die at low cost without the need to sufficiently polish it to a mirror surface, and by changing the molding material with one die, it is possible to manufacture various matte products and mirror products, so it is cheap and easy. In addition, it is possible to provide acrylic resin molded articles having various types of matte surface states, which is advantageous.

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Claims (5)

[Claims] 1. Particles having an average particle size in the range of 4 to 15 μm and a particle size of less than 10 μm are based on 100 parts by weight of a methyl methacrylate polymer which is a copolymer or homopolymer containing 80% or more of methyl methacrylate. 0.5% of crosslinked methacrylic acid ester polymer fine particles and / or high degree of polymerization methacrylic acid ester polymer fine particles occupying 65% or more in distribution
An acrylic resin composition for injection-molded articles, which contains up to 15 parts by weight and has excellent matting properties. 2. The acrylic resin composition according to claim 1, wherein the fine particles are crosslinked polymer fine particles containing methyl methacrylate as a main component and / or high polymerization degree polymer fine particles. 3. The acrylic resin composition according to claim 1, wherein the fine particles are crosslinked polymethylmethacrylate fine particles and / or high degree of polymerization polymethylmethacrylate fine particles. 4. An acrylic resin molded article excellent in mattness, which is obtained by injection molding the acrylic resin composition according to claim 1. 5. A method for obtaining an acrylic resin molded article by injection-molding an acrylic resin material, wherein the acrylic resin composition according to claim 1 is injected into a mold cavity that has not been frosted. A method for producing an acrylic resin molded article having excellent mattness, which is characterized by