Patent ID: 8546469

Claim:
A glass fiber-reinforced polyester resin composition including: (A) about 30 to about 80 wt % of two or more kinds of polyester resin; (B) about 20 to about 70 wt % of a vinyl-based copolymer comprising an acrylic-based graft copolymer or a mixture of the acrylic-based graft copolymer and a copolymer of aromatic vinyl monomers and unsaturated nitrile monomers; and (C) about 10 to about 100 parts by weight of glass fiber, based on about 100 parts by weight of the total amount of the polyester resin (A) and the vinyl-based copolymer (B), wherein the polyester resin (A) includes polyethylene terephthalate resin having a crystallinity of about 40% to about 60% and polybutylene terephthalate resin; and wherein the polyester resin (A) includes about 10 to about 40% of the polyethylene terephthalate resin and about 60% to about 90% of the polybutylene terephthalate resin; wherein the acrylic-based graft copolymer is a copolymer in which a polymer of aromatic vinyl monometers and unsaturated nitrile monomers is grafted onto an acrylic-based rubber; and wherein the composition has a fluidity of 25 to 33 g/1 min measured in accordance with ASTM D1238 and a shrinkage ratio (TD) of 0.65 to 0.73%.