US4463121A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thermoforming partially crystalline polyester articles
Assignee: Corpus Christi Polymers LLC
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Filing: 1982-08-18
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Granted: 1984-07-31
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Expires: 2002-08-18
Abstract
Abstract Thin walled thermoformed articles of partially crystallized polyethylene terephthalate containing a minor component of a polyolefin which exhibit improved impact resistance and high temperature dimensional stability. Method for thermoforming such articles using polyethylene terephthalate/polyolefin blends which give improved mold release.
Inventors
- 👤 Robert J. Gartland
- 👤 Joseph N. Feil
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 06:28
CPC Classifications
B; B29; B29C; B29C51/00; B29C51/002; C; C08; C08L; C08L67/00; C08L67/02; B29K; B29K2023/00; B29K2067/00; Y; Y10; Y10T; Y10T428/00; Y10T428/13; Y10T428/1352; Y10T428/1397
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
86 words
A thermoformed, non-oriented, heat set, thin walled article, the composition consisting of: (A) from about 98 to about 95 weight percent of polyethylene terephthalate with an intrinsic viscosity as measured in a 60/40 by volume mixed solvent of phenol/tetrachloroethane at 30° C. from about 0.65 to about 1.2; and (B) from about 2 to about 5 weight percent of a polyolefin with repeat units derived from olefin monomers containing 2 to 6 carbon atoms, said article having a total crystallinity from about 10 to about 30%.
Claim 2
Dependent Claim
86 words
A thermoformed, non-oriented, heat set, thin walled article, the composition consisting of: (A) from about 98 to about 95 weight percent of polyethylene terephthalate with an intrinsic viscosity as measured in a 60/40 by volume mixed solvent of phenol/tetrachloroethane at 30° C. from about 0.65 to about 1.2; and (B) from about 2 to about 5 weight percent of a polyolefin with repeat units derived from olefin monomers containing 2 to 6 carbon atoms, said article having a total crystallinity from about 10 to about 30%.
Claim 3
Dependent Claim
99 words
A thermoformed, non-oriented, heat set, thin walled article, the composition consisting of: (A) from about 98 to about 93 weight percent of polyethylene terephthalate with intrinsic viscosity as measured in a 60/40 by volume mixed solvent of phenol/tetrachloroethane at 30° C. from about 0.65 to about 1.2; and (B) from about 2 to about 5 weight percent of a polyolefin with repeat units derived from olefin monomers containing 2 to 6 carbon atoms; and (C) from about 0.05 to about 2.0 weight percent of a heat stabilizer said article having a total crystallinity from about 10 to about 30%.
Claim 4
Dependent Claim
99 words
A thermoformed, non-oriented, heat set, thin walled article, the composition consisting of: (A) from about 98 to about 93 weight percent of polyethylene terephthalate with intrinsic viscosity as measured in a 60/40 by volume mixed solvent of phenol/tetrachloroethane at 30° C. from about 0.65 to about 1.2; and (B) from about 2 to about 5 weight percent of a polyolefin with repeat units derived from olefin monomers containing 2 to 6 carbon atoms; and (C) from about 0.05 to about 2.0 weight percent of a heat stabilizer said article having a total crystallinity from about 10 to about 30%.
Claim 5
Dependent Claim
14 words
An article as described in claims 1 or 2 wherein said polyolefin is polyethylene.
Claim 6
Dependent Claim
15 words
An article as described in claim 1 wherein said polyethylene is linear low density polyethylene.
Claim 7
Dependent Claim
32 words
An article as described in claim 2 wherein said polyethylene is linear low density polyethylene, said heat stabilizer is a polyphenol selected from the group consisting of 1,3,5-Trimethyl-2,4,6-tris(3,5-di-t butyl-4-hydroxybenzyl)benzene, and tetrakis(methylene3-(3,5-ditertiary butyl-4-hydroxyphenyl)-propionate)methane.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-07-31 | 1988-01-30 | 1988-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-07-31 | 1992-01-30 | 1992-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-07-31 | 1996-01-30 | 1996-07-31 | $7700.00 | Window Closed / Lapsed |