RUBBER MODIFIED ACRYLIC RESIN COMPOSITION EXCELLENT IN JET-BLACKNESS AND MOLDED PRODUCT THEREOF
A jet-black rubber modified acrylic resin composition comprising: a rubber modified acrylic resin (A); and a carbon black (B) blended with the resin (A), the rubber modified acrylic resin (A) being capable of providing a 3-mm-thick molded product that has transparency with a total light transmittance of 85% or higher, and the carbon black being dispersed in the resin composition and having a particle diameter of 10 to 40 nm.
1 . A jet-black rubber modified acrylic resin composition comprising:
100 parts by weight of a rubber modified acrylic resin (A); and
0.05 to 5 parts by weight of a carbon black (B) blended with the resin (A) by means of melt kneading,
the rubber modified acrylic resin (A) being capable of providing a 3-mm-thick molded product that has transparency with a total light transmittance of 85% or higher, and
the carbon black being dispersed in the resin composition with a dispersion particle diameter of 10 to 40 nm.
2 . The rubber modified acrylic resin composition according to claim 1 ,
wherein 100 parts by weight of the rubber modified acrylic resin (A) contains 5 to 100 parts by weight of a rubber-containing acrylic graft copolymer (A1) and 95 to 0 parts by weight of an acrylic resin (A2);
the rubber-containing acrylic graft copolymer (A1) is a multilayer graft copolymer having an inner layer of a rubber copolymer (A1c) and an outer layer of a graft component (A1s) with a weight ratio (A1c:A1s) of 5:95 to 85:15, the outer layer covering the inner layer;
the rubber copolymer (A1c) is a polymer of 100% by weight of monomers for rubber copolymer containing 50 to 99.9% by weight of an alkyl acrylate, 0 to 49.9% by weight of another copolymerizable vinyl monomer, and 0.1 to 10% by weight of a polyfunctional monomer;
the graft component (A1s) is a polymer of 100% by weight of monomers for graft component containing 50 to 100% by weight of an alkyl methacrylate and 0 to 50% by weight of a copolymerizable vinyl monomer other than the alkyl methacrylate; and
the acrylic resin (A2) is a polymer of monomers for acrylic resin containing 0 to 50% by weight of an alkyl acrylate and 100 to 50% by weight of an alkyl methacrylate.
3 . The rubber modified acrylic resin composition according to claim 2 ,
wherein the rubber-containing acrylic graft copolymer (A1) has a number average particle diameter of 30 to 400 nm.
4 . The rubber modified acrylic resin composition according to claim 2 ,
wherein the rubber-containing acrylic graft copolymer (A1) is a multilayer graft copolymer which has at least three layers, which further has an innermost layer polymer (A1a) with a weight ratio (A1a:(sum of A1c and A1s)) of 10:90 to 40:60, and which is obtained by polymerization of the monomers for rubber copolymer in the presence of the innermost layer polymer (A1a); and
the innermost layer polymer (A1a) is a polymer of 100% by weight of monomers for innermost layer polymer containing 40 to 99.9% by weight of one or more monomers selected from the group consisting of alkyl methacrylates and aromatic vinyl compounds, 59.9 to 0% by weight of another copolymerizable vinyl monomer, and 0.1 to 5% by weight of a polyfunctional monomer.
5 . A molded product, which is prepared by molding the rubber modified acrylic resin composition according to claim 1 .
6 . The molded product according to claim 5 ,
wherein the molded product formed into a plate shape by injection molding with a mirror-polished mold has an L value of 0 to 8, the L value being measured with a 0° to 45° spectroscopic color difference meter in conformity with JIS Z 8722.
7 . The molded product according to claim 6 ,
wherein the difference of L values of the molded product before and after a weather resistance test measured with a color difference meter is between 0 and 1,
the molded product being formed into a plate shape by injection molding with a mirror-polished mold, and
the test being in conformity with JIS K 7350-4 and performed for 1,000 hours under the following conditions: black panel 63° C., with rain, and 255 W/m 2 .
8 . The rubber modified acrylic resin composition according to claim 3 ,
wherein the rubber-containing acrylic graft copolymer (A1) is a multilayer graft copolymer which has at least three layers, which further has an innermost layer polymer (A1a) with a weight ratio (A1a:(sum of A1c and A1s)) of 10:90 to 40:60, and which is obtained by polymerization of the monomers for rubber copolymer in the presence of the innermost layer polymer (A1a); and
the innermost layer polymer (A1a) is a polymer of 100% by weight of monomers for innermost layer polymer containing 40 to 99.9% by weight of one or more monomers selected from the group consisting of alkyl methacrylates and aromatic vinyl compounds, 59.9 to 0% by weight of another copolymerizable vinyl monomer, and 0.1 to 5% by weight of a polyfunctional monomer.
9 . A molded product, which is prepared by molding the rubber modified acrylic resin composition according to claim 2 .
10 . A molded product, which is prepared by molding the rubber modified acrylic resin composition according to claim 3 .
11 . A molded product, which is prepared by molding the rubber modified acrylic resin composition according to claim 4 .
12 . The rubber modified acrylic resin composition according to claim 1 ,
which is prepared by using a carbon black masterbatch containing the carbon black.