Polyester resin composition, and light reflector component and light reflector including polyester resin composition

A polyester resin composition comprising:

• a polyester resin A containing
• 50 to 100 mass % of a polybutylene terephthalate resin, and
• 0 to 50 mass % of a polyethylene terephthalate resin;
• a metal organic acid salt B,
• wherein the metal organic salt B is either or both of an alkali metal organic acid salt and an alkaline earth metal organic acid salt;
• a styrenic resin C, and
• wherein the styrenic resin C is present in an amount of 0.5 to 10 parts by mass of a styrenic resin C relative to 100 parts by mass of the polyester resin A;
• and
• an inorganic filler D,
• wherein the inorganic filler D is present in an amount of 1 to 20 parts by mass of the inorganic filler D relative to 100 parts by mass of the polyester resin A,
• wherein the polyester resin composition comprises 0.000005 to 0.05 parts by mass of either or both of the alkali metal atom of the alkali metal organic acid salt and the alkaline earth metal atom of the alkali metal organic acid salt relative to 100 parts by mass of the polyester resin A,
• wherein in the polyester resin composition, an amount of linear oligomers of polybutylene terephthalate or an amount of the linear oligomers of polybutylene terephthalate and linear oligomers of polyethylene terephthalate is less than or equal to 1000 mg/kg,
• wherein the inorganic filler D has an average particle size of 0.05 to 3 μm, and
• wherein the metal organic acid salt B is one or two or more selected from the group consisting of lithium acetate, sodium acetate, potassium acetate, calcium acetate, magnesium acetate, lithium benzoate, and potassium benzoate.