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US4318763A
Expired / Lapsed
US
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Sealing cross-linked thermoplastic materials
Assignee: WR Grace and Co Conn
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Filing: 1980-09-15
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Granted: 1982-03-09
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Expires: 2000-09-15
Abstract
Abstract A method of improving the high temperature strength of a heat seal which bonds cross-linkable thermoplastic material together by first forming the heat seal and then irradiating the seal area with ionizing radiation to increase the cross-linking in the material of the seal area by at least 2 MR.
Inventors
- 👤 Anne C. Bieler
- 👤 Milton A. Howe, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:35
CPC Classifications
B; B32; B32B; B32B7/00; B32B7/04; B29; B29C; B29C66/00; B29C66/70; B29C66/71; B29C65/00; B29C65/48; B29C65/4805; B29C65/483; B29C65/4845; B29C66/72; B29C66/723; B29C66/73; B29C66/737; B29C66/7371; B29C66/73711; B29C66/73715; B29C66/7375; B29C66/73755; B29C66/73756; B29C66/739; B29C66/7392; B29C66/73921; B29C66/7394; B29C66/73941; B32B27/00; B32B27/06; B32B27/08; C; C08; C08J; C08J5/00; C08J5/12; C08J5/121; B29C35/00; B29C35/02; B29C35/08; B29C35/0866; B29C2035/0877; B29C65/02; B29C65/14; B29C65/1403; B29C66/73751; B29C66/73752; B29C71/00; B29C71/04; B29K; B29K2023/00; B29K2023/04; B29K2023/06; B29K2023/08; B29K2023/083; B29K2023/10; B29K2023/12; B29K2031/00; B29K2031/04; B29K2105/00; B29K2105/0085; B29K2105/24; B29K2995/00; B29K2995/0037; B29K2995/0049; B29L; B29L2009/00; B29L2023/00; B29L2023/001; B32B2305/00; B32B2305/72; B32B2307/00; B32B2307/30; B32B2307/31; B32B2310/00; B32B2310/08; B32B2310/0875; B32B2310/0881; B32B2439/00; C08J2323/00; C08J2323/02; C08J2323/04; Y; Y10; Y10T; Y10T156/00; Y10T156/10; Y10T156/1002; Y10T156/1005; Y10T428/00; Y10T428/13; Y10T428/1328; Y10T428/1331; Y10T428/31504; Y10T428/31855; Y10T428/31909; Y10T428/31913; Y10T428/3192
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
138 words
A method of making a flexible, heat shrinkable receptacle from thermoplastic film having improved high temperature seal strength comprising the steps of: (a) selecting a thermoplastic film having at least one layer selected from the group consisting of polyethylenes and ethylene vinyl acetate copolymers which have been cross-linked by ionizing radiation, said film having a sealing surface wherein the material forming the surface is selected from the group consisting of polyethylenes and ethylene-vinyl acetate copolymers; (b) orienting said film to render it heat shrinkable; (c) placing said sealing surfaces in a face-to-face relationship; (d) heat sealing selected portions of said surface together to form a receptacle; (e) irradiating said sealed together surfaces with ionizing radiation to a dosage level of at least 2 MR thereby increasing the high temperature strength of the seals of said heat shrinkable receptacle.
Claim 2
Independent Claim
138 words
A method of making a flexible, heat shrinkable receptacle from thermoplastic film having improved high temperature seal strength comprising the steps of: (a) selecting a thermoplastic film having at least one layer selected from the group consisting of polyethylenes and ethylene vinyl acetate copolymers which have been cross-linked by ionizing radiation, said film having a sealing surface wherein the material forming the surface is selected from the group consisting of polyethylenes and ethylene-vinyl acetate copolymers; (b) orienting said film to render it heat shrinkable; (c) placing said sealing surfaces in a face-to-face relationship; (d) heat sealing selected portions of said surface together to form a receptacle; (e) irradiating said sealed together surfaces with ionizing radiation to a dosage level of at least 2 MR thereby increasing the high temperature strength of the seals of said heat shrinkable receptacle.
References Cited (Backward Citations)
US2936261A
Cited
US3106441A
Cited
US3891008A
Cited
US4044187A
Cited
US4044187B1
Cited
US3997385A
Cited
US4127688A
Cited
US4225373A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-03-08 | 1985-09-07 | 1986-03-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-03-08 | 1989-09-07 | 1990-03-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-03-08 | 1993-09-07 | 1994-03-09 | $7700.00 | Window Closed / Lapsed |