Eastman-kodak Company

James C Weaver

Robert W Seymour

Wayne P Pruett

Benny W Wright

Theodore F Gray, Jr

Compositions suitable for molding are produced by examining a (1) polyethylene terephthalate polyester, (2) a low molecular weight polyethylene mold release agent (3) talc as nucleating agent, (4) carbon black, (5) a hindered phenolic antioxidant and (6) other optional ingredients such as reinforcing glass fibers.

Polyester compositions

Stampable sheet of reinforced thermoplastic material having a plurality of layers of polymeric material and a plurality of layers of fibrous reinforcing material alternating with the layers of polymeric material, the polymeric material layers having minimum crystallization half-times upon heating of one minute or less with the fifth layer of the sheet being polymeric material having a shrinkage of less than 2% as determined in accordance with ASTM Method D-955, and the first or outer layer and the third layer of the sheet being polymeric material layers having about 5 to about 50 weight percent fillers; with all of the layers being integrally formed together and possessing a smooth surface, essentially free of fiber 'read-through', and having more uniform reinforcement in the sheet, and of the type required of exterior automotive-type appearance parts; and a stamped sheet formed from the stampable sheet and having a heat deflection temperature under 264 psi. load greater than T.sub.m -50.degree. C., where T.sub.m is the melting point in the outer layers of the sheet.

Stampable reinforced thermoplastic polyester sheet with improved surface

Stampable sheet of reinforced thermoplastic material having a plurality of layers of polymeric material and a plurality of layers of fibrous reinforcing material alternating with the layers of polymeric material, the polymeric material layers having minimum crystallization half-time upon heating of one minute or less and the polymeric material layer inwardly of the outer polymeric material layers and contiguous to a surfacing mat layer having a shrinkage of less than 2% as determined in accordance with ASTM Method D-955; with all of the layers being integrally formed together and possessing a smooth surface, essentially free of fiber 'read-through', and of the type required of exterior automotive-type appearance parts; and a stamped sheet formed from the stampable sheet and having a heat deflection temperature under 264 psi load greater than T.sub.m -50.degree. C. wherein T.sub.m is the melting point of the outer layers of the sheet.

Stampable reinforced thermoplastic polyester sheets

The object of the invention is to provide a stampable sheet of reinforced thermoplastic material, the sheet being composed of a plurality of layers of polyester material and a plurality of layers of reinforcing material integrally formed together, the central layer or layers of polyester material being of more slowly crystallizing material than the outer layers. The polyester layers are all substantially amorphous and are made of polyester polymers selected from poly(ethylene terephthalate), selected copolymers of poly(ethylene terephthalate), poly(1,4-cyclohexylenedimethylene terephthalate), selected copolymers of poly(1,4-cyclohexylenedimethylene terephthalate), blends of poly(ethylene terephthalate) and any of the aforementioned selected copolymers, and blends of poly(1,4-cyclohexylenedimethylene terephthalate) and any of the aforementioned selected copolymers, The central polyester layer or layers are polyester polymers selected from the aforementioned selected copolymers and blends. Another object of the invention is to provide a stamped sheet from the stampable sheet of reinforced thermoplastic material, the stamped sheet having a heat deflection temperature under 264 psi. load greater than T.sub.m -50.degree. C.

Disclosed is a composition comprised of an admixture of poly(tetramethylene terephthalate), bisphenol A polycarbonate and selected phosphorous compounds.

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Kingsport, TN, United States of America

James C Weaver