Patent US4476170A successfully refreshed from Google Patents.
US4476170A
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Poly(ethylene terephthalate) articles and method
Assignee: Graham Packaging Plastic Products Inc
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Filing: 1983-12-02
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Granted: 1984-10-09
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Expires: 2003-12-02
Abstract
Abstract Disclosed is a process of making an oriented and heat set blow molded bottle of poly(ethylene terephthalate) so that the bottles resulting from the process have a density over 1.3860 cc./gm. and an onset-of-shrinkage temperature over 80° C. In the process preform preheated to a temperature suitable for orientation is biaxially stretched in a blow mold and then while the hollow article walls are still in contact with the blow mold walls, the article is raised to a higher heat setting temperature in the range of 200°-250° C. (except for the neck) thus heat setting the bottle, and while the article is still at a shrinkage resisting pressure exceeding atmospheric cooling the article to a temperature at which it maintains its shape when not pressurized but not below 100° C. It is also particularly disclosed that this cooling step can be done outside the mold. In a special embodiment of the invention where the cooling step is effected outside the mold, the cooling under the shrinkage resisting pressure is below 100° C., even down to room temperature and lower, before the shrinkage resisting pressure is released from the hollow article.
Inventors
- 👤 Saleh A. Jabarin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:09
CPC Classifications
B; B29; B29C; B29C71/00; B29C71/02; B29C49/00; B29C49/42; B29C49/64; B29C49/6472; B29C49/78; B29C49/786; B29C2049/7864; B29C2049/78645; B29C2949/00; B29C2949/07; B29C2949/0715; B29C49/02; B29C49/06; B29K; B29K2067/00; B29K2067/003; B29L; B29L2031/00; B29L2031/712; B29L2031/7158; Y; Y10; Y10T; Y10T428/00; Y10T428/13; Y10T428/1352; Y10T428/1397
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
44 words
A transparent hollow article of poly(ethylene terephthalate) having an inherent viscosity of at least 0.6 dl./gm., the body portion of said article being biaxially oriented and heat set and having a density over 1.392 g/cc and a volume shrinkage of less than about 6%.
Claim 2
Dependent Claim
44 words
A transparent hollow article of poly(ethylene terephthalate) having an inherent viscosity of at least 0.6 dl./gm., the body portion of said article being biaxially oriented and heat set and having a density over 1.392 g/cc and a volume shrinkage of less than about 6%.
Claim 3
Dependent Claim
44 words
A transparent hollow article of poly(ethylene terephthalate) having an inherent viscosity of at least 0.72 dl./gm., the body portion of said article being biaxially oriented and heat set and having a density over 1.392 g/cc and a volume shrinkage of less than about 5%.
Claim 4
Dependent Claim
44 words
A transparent hollow article of poly(ethylene terephthalate) having an inherent viscosity of at least 0.72 dl./gm., the body portion of said article being biaxially oriented and heat set and having a density over 1.392 g/cc and a volume shrinkage of less than about 5%.
Claim 5
Dependent Claim
21 words
An article as defined in claim 2 in which the density of the heat set sidewall is over about 1.393 g/cc.
Claim 6
Dependent Claim
180 words
A transparent hollow article or oriented polyethylene terephthalate that is heat set and that has an onset of shrinkage temperature of at least about 105° C. and a shrinkage of less than about 5% of the volume, the article being a hollow container with a body including an oriented sidewall, the oriented sidewall being heat treated to increase the density thereof to at least about 1.392 g/cc by heating to a temperature equivalent to a temperature of about 220° C. to 250° C., the heat treated sidewall being quenched while under a shrinkage reducing pressure to provide the article with a shrinkage of less than about 5% of the volume and an onset of shrinkage temperature of at least about 105° C., the quenching being done at a temperature equivalent to that of about room temperature to 170° C. at a high heat setting temperature of 240° C., about 80° C. to 160° C. for a heat setting temperature of about 230° C., and about 120° C. to 140° C. for a lower heat setting temperature of about 220° C.
Claim 7
Dependent Claim
180 words
A transparent hollow article or oriented polyethylene terephthalate that is heat set and that has an onset of shrinkage temperature of at least about 105° C. and a shrinkage of less than about 5% of the volume, the article being a hollow container with a body including an oriented sidewall, the oriented sidewall being heat treated to increase the density thereof to at least about 1.392 g/cc by heating to a temperature equivalent to a temperature of about 220° C. to 250° C., the heat treated sidewall being quenched while under a shrinkage reducing pressure to provide the article with a shrinkage of less than about 5% of the volume and an onset of shrinkage temperature of at least about 105° C., the quenching being done at a temperature equivalent to that of about room temperature to 170° C. at a high heat setting temperature of 240° C., about 80° C. to 160° C. for a heat setting temperature of about 230° C., and about 120° C. to 140° C. for a lower heat setting temperature of about 220° C.
Claim 8
Dependent Claim
24 words
An article as defined in claim 4 in which the sidewall is heat set at about 230° C. and quenched at about 100° C.
Claim 9
Dependent Claim
24 words
An article as defined in claim 4 in which the sidewall is heat set at about 240° C. and quenched at about 180° C.
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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) | 1987-10-09 | 1988-04-09 | 1988-10-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-10-09 | 1992-04-09 | 1992-10-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-10-09 | 1996-04-09 | 1996-10-09 | $7700.00 | Window Closed / Lapsed |