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US4263364A Expired / Lapsed US ⏱️ 0.0 years remaining

Stampable reinforced thermoplastic polyester sheets

Assignee: Eastman Chemical Co
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Filing: 1979-12-14
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Granted: 1981-04-21
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Expires: 1999-12-14
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Abstract

Abstract 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 Tm -50 DEG C.

Inventors

  • 👤 Robert W. Seymour
  • 👤 James C. Weaver
  • 👤 Benny W. Wright

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 23:52
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/36; B29; B29C; B29C51/00; B29C51/002; B32B27/12; B32B27/34; B32B37/00; B32B2262/00; B32B2262/10; B32B2262/101; B32B2305/00; B32B2305/08; B32B2307/00; B32B2307/70; B32B2307/702; B32B2367/00; Y; Y10; Y10T; Y10T428/00; Y10T428/249921; Y10T428/249924; Y10T428/24994; Y10T428/24995; Y10T428/31504; Y10T428/31551; Y10T428/31616

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 234 words
A stampable sheet of reinforced thermoplastic material, said sheet comprising 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; said polyester layers being substantially amorphous and made of polyester polymers selected from the group consisting of a. poly(ethylene terephthalate); b. copolymers of poly(ethylene terephthalate) having about 5 to about 50 mole percent of 1,4-cyclohexanedimethanol, neopentyl glycol, 2,2,4,4-tetramethyl-1,3-cyclobutanediol, bisphenol A, isophthalic acid or 1,4-cyclohexanedicarboxylic acid; c. poly(1,4-cyclohexylenedimethylene terephthalate); d. copolymers of poly(1,4-cyclohexylenedimethylene terephthalate) having about 20 to about 50 mole percent of ethylene glycol, neopentyl glycol, 2,2,4,4-tetramethyl-1,3-cyclobutanediol, bisphenol A, isophthalic acid, or 1,4-cyclohexanedicarboxylic acid; e. blends of poly(ethylene terephthalate) with greater than 35 weight percent of any of said copolymers in item (b) or item (d); and f. blends of poly(1,4-cyclohexylene dimethylene terephthalate) with greater than 35 weight percent of any of said copolymers in item (b) or item (d); said outer polyester layers having a minimum crystallization half-time upon heating of one minute or less, and said central polyester layer or layers being selected from the polymers identified in items b, d, e or f above and having a minimum crystallization half-time upon heating of greater than one minute, the minimum crystallization half-time being that as measured with respect to each individual layer of said polyester material.
Claim 2
Dependent Claim 234 words
A stampable sheet of reinforced thermoplastic material, said sheet comprising 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; said polyester layers being substantially amorphous and made of polyester polymers selected from the group consisting of a. poly(ethylene terephthalate); b. copolymers of poly(ethylene terephthalate) having about 5 to about 50 mole percent of 1,4-cyclohexanedimethanol, neopentyl glycol, 2,2,4,4-tetramethyl-1,3-cyclobutanediol, bisphenol A, isophthalic acid or 1,4-cyclohexanedicarboxylic acid; c. poly(1,4-cyclohexylenedimethylene terephthalate); d. copolymers of poly(1,4-cyclohexylenedimethylene terephthalate) having about 20 to about 50 mole percent of ethylene glycol, neopentyl glycol, 2,2,4,4-tetramethyl-1,3-cyclobutanediol, bisphenol A, isophthalic acid, or 1,4-cyclohexanedicarboxylic acid; e. blends of poly(ethylene terephthalate) with greater than 35 weight percent of any of said copolymers in item (b) or item (d); and f. blends of poly(1,4-cyclohexylene dimethylene terephthalate) with greater than 35 weight percent of any of said copolymers in item (b) or item (d); said outer polyester layers having a minimum crystallization half-time upon heating of one minute or less, and said central polyester layer or layers being selected from the polymers identified in items b, d, e or f above and having a minimum crystallization half-time upon heating of greater than one minute, the minimum crystallization half-time being that as measured with respect to each individual layer of said polyester material.
Claim 3
Dependent Claim 19 words
A stampable sheet as defined in claim 1, wherein said layers of reinforcing material are comprised of glass fiber.
Claim 4
Dependent Claim 38 words
A stampable sheet as defined in claim 1, wherein said sheet comprises at least three layers of said polyester material and at least two layers of glass fiber, said polyester layers being alternated with said glass fiber layers.
Claim 5
Dependent Claim 109 words
A stampable sheet as defined in claim 1, wherein said outer polyester layers comprise poly(ethylene terephthalate) having an inherent viscosity of about 0.3 to about 0.7 and a minimum crystallization half-time of about 40 seconds; said central polyester layer or layers comprise copoly(69/31 ethylene terephthalate/1,4-cyclohexylenedimethylene terephthalate) having an inherent viscosity of about 0.60 and a minimum crystallization half-time of about 2650 minutes; and said layers of reinforcing material comprise glass fibers; said inherent viscosity being determined by a concentration of 0.5 grams polymer in 100 milliliter solvent (60% by weight phenol and 40% by weight tetrachloroethane), the polymer being dissolved at 125° C. and being measured at 25° C.
Claim 6
Dependent Claim 110 words
A stampable sheet as defined in claim 1, wherein said outer polyester layers comprise poly(ethylene terephthalate) having an inherent viscosity of about 0.3 to about 0.7 and a minimum crystallization half-time of about 40 seconds; said central polyester layer or layers comprise copoly(87/13 ethylene terephthalate/1,4-cyclohexylenedimethylene terephthalate) having an inherent viscosity of about 0.65 and a minimum crystallization half-time of about 9 minutes; and said layers of reinforcing material comprise glass fibers; said inherent viscosity being determined by a concentration of 0.5 grams polymer in 100 milliliter of solvent (60% by weight phenol and 40% by weight tetrachloroethane), the polymer being dissolved at 125° C. and being measured at 25° C.
Claim 7
Dependent Claim 84 words
A stampable sheet as defined in claim 1, wherein said central layer or layers comprise a blend of poly(ethylene terephthalate) having about 50% by weight copoly(87/13 ethylene terephthalate/1,4-cyclohexylenedimethylene terephthalate) having an inherent viscosity of about 0.60 and a minimum crystallization half-time of about 1.5 minutes; said inherent viscosity being determined by a concentration of 0.5 grams polymer in 100 milliliter of solvent (60% by weight phenol and 40% by weight tetrachloroethane), the polymer being dissolved at 125° C. and being measured at 25° C.
Claim 8
Dependent Claim 41 words
A stampable sheet as defined in claim 1, wherein the overall thickness of said sheet ranges from about 40 to about 250 mils, and said layers of glass fibers comprise about 20 to about 50% by weight of said stampable sheet.
Claim 9
Dependent Claim 42 words
A stampable sheet as defined in claim 1, wherein the overall thickness of said sheet ranges from about 50 to about 150 mils, and said layers of glass fibers comprise about 20 to about 50 percent by weight of said stampable sheet.
Claim 10
Dependent Claim 41 words
A stampable sheet as defined in claim 1, wherein the overall thickness of said sheet ranges from about 60 to about 100 mils, and said layers of glass fibers comprise about 30 to about 40% by weight of said stampable sheet.
Claim 11
Dependent Claim 30 words
A stamped sheet of reinforced thermoplastic material from the stampable sheet of claim 1 and having a heat deflection temperature under 264 psi. load greater than T m -50° C.
Claim 12
Dependent Claim 19 words
A stamped sheet as defined in claim 10, wherein said layers of reinforcing material are comprised of glass fiber.
Claim 13
Dependent Claim 37 words
A stamped sheet as defined in claim 10, wherein said sheet comprises at least three layers of said polyester material and at least two layers of glass fiber, said polyester layers being alternated with said glass fibers.
Claim 14
Dependent Claim 14 words
A stamped sheet of reinforced thermoplastic material from the stampable sheet of claim 4.
Claim 15
Dependent Claim 14 words
A stamped sheet of reinforced thermoplastic material from the stampable sheet of claim 5.
Claim 16
Dependent Claim 14 words
A stamped sheet of reinforced thermoplastic material from the stampable sheet of claim 6.

References Cited (Backward Citations)

US2961365A Cited
US3765998A Cited
US3993828A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-04-20 1984-10-20 1985-04-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-04-20 1988-10-20 1989-04-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-04-20 1992-10-20 1993-04-21 $7700.00 Window Closed / Lapsed

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