Thermoplastic resin composition for light reflector, formed article for light reflector, light reflector, and method for producing formed article for light reflector

A thermoplastic resin composition for a light reflector comprising:

• a thermoplastic resin (A);
• and
• barium sulfate;
• wherein
• a content of the barium sulfate is 2 to 45 parts by mass per 100 parts by mass of the thermoplastic resin (A),
• a refractive index α of the barium sulfate is from 1.61 to 2.5 and
• an average particle diameter of the barium sulfate is from 0.05 to 1 μm;
• the thermoplastic resin (A) comprises:
• polybutylene terephthalate;
• polyethylene terephthalate;
• and
• from 4 to 10 mass % of at least one vinyl copolymer thermoplastic resin selected from the group of vinyl thermoplastic resins consisting of an acrylonitrile-styrene copolymer resin having a mass ratio of acrylonitrile to styrene of from 20/80 to 45/55, an epoxy group containing acrylonitrile-styrene copolymer resin having a % by mass composition of 0.1 to 0.4% glycidyl methacrylate, 15 to 40% acrylonitrile and 60 to 84.9% styrene and a maleimide copolymer resin of N-phenyl maleimide/styrene/acrylonitrile having 15 to 60 mass % N-phenyl maleimide;
• wherein
• a mass ratio of polybutylene terephthalate to polyethylene terephthalate is from 95/5 to 55/45.