Patent US4521500A successfully refreshed from Google Patents.
US4521500A
Expired / Lapsed
US
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Leak-proof alkaline cell
Assignee: Maxell Ltd
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Filing: 1982-12-01
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Granted: 1985-06-04
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Expires: 2002-12-01
Abstract
Abstract An improved leak-proof alkaline cell comprising positive and negative electrode materials, a member for accommodating said positive electrode materials, a member for covering said negative electrode materials and a gasket provided between the members, characterized in that a sealant comprising asphalt and a compound selected from the group consisting of homopolymer of vinyl acetate, copolymer of vinyl acetate and polyterpene is interposed between the gasket and at least one of said members.
Inventors
- 👤 Osamu Watanabe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 10:38
CPC Classifications
H; H01; H01M; H01M50/00; H01M50/10; H01M50/183; H01M50/19; H01M50/193; H01M50/186; Y; Y02; Y02E; Y02E60/00; Y02E60/10
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
73 words
A leak-proof alkaline cell comprising positive and negative electrode materials, a member for accommodating said positive electrode materials, a member for covering said negative electrode materials and a gasket made of a polyamide provided between the members, characterized in that a sealant comprising asphalt and a ethylene-vinyl acetate copolymer in an amount of 0.5 to 25% by weight of said asphalt is interposed between said gasket and at least one of said members.
Claim 2
Dependent Claim
73 words
A leak-proof alkaline cell comprising positive and negative electrode materials, a member for accommodating said positive electrode materials, a member for covering said negative electrode materials and a gasket made of a polyamide provided between the members, characterized in that a sealant comprising asphalt and a ethylene-vinyl acetate copolymer in an amount of 0.5 to 25% by weight of said asphalt is interposed between said gasket and at least one of said members.
Claim 3
Dependent Claim
22 words
The cell according to claim 1, wherein the sealant is interposed between the gasket and the member covering the negative electrode materials.
Claim 4
Dependent Claim
13 words
The cell according to claim 1, wherein the asphalt is a straight asphalt.
Claim 5
Dependent Claim
19 words
The cell according to claim 3, wherein the straight asphalt has a softening point not less than 60° C.
Claim 6
Dependent Claim
22 words
The cell according to claim 1, wherein the amount of copolymer of ethylene-vinyl acetate is 0.5 to 10% by weight of asphalt.
References Cited (Backward Citations)
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JPS5516344A
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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) | 1988-06-03 | 1988-12-03 | 1989-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-06-03 | 1992-12-03 | 1993-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-06-03 | 1996-12-03 | 1997-06-04 | $7700.00 | Window Closed / Lapsed |