Patent ID: 8053597

Claim:
A terephthalic acid composition comprising: (1) terephthalic acid in an amount greater than 90 percent by weight; (2) (a) 4-carboxybenzaldehyde in an amount ranging from 1 ppm to 1000 ppm; or (b) p-toluic acid in an amount ranging from 1 ppm to 1000 ppm; or both (2) (a) and (2) (b); and (3) at least two of the following: (a) isophthalic acid in an amount ranging from 50 ppm to 2000 ppm; (b) trimellitic acid in an amount ranging from 140 ppm to 1000 ppm; (c) 4,4′-dicarboxybiphenyl in an amount ranging from 20 ppm to 150 ppm; (d) phthalic acid in an amount ranging from 20 ppm to 1000 ppm; (e) 4-hydroxybenzoic acid in an amount ranging from 3 ppm to 1000 ppm; (f) 4-hydroxymethylbenzoic acid in an amount ranging from 40 ppm to 200 ppm; and (g) benzoic acid in an amount ranging from 50 ppm to 500 ppm; (4) and at least one of the following present in an amount not greater than 0.5 wt % antimony catalysts, titanium catalysts, dyes, pigments, reheat agents, antioxidants, thermal stabilizers, UV stabilizers, coupling or chain-extending agents, end-capping agents, telechelic modifiers, acetaldehyde reducing agents, agents to reduce formation of diethylene glycol (DEG), titanium dioxide, and optical brightener.