Patent US4387144A successfully refreshed from Google Patents.
US4387144A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Battery separator material
Assignee: Tullis Russell and Co Ltd
•
Filing: 1979-05-01
•
Granted: 1983-06-07
•
Expires: 1999-05-01
Abstract
Abstract A battery separator having a low electrical resistance after extended use is made by thermal consolidation and thermal embossing of a paper web formed from a furnish containing a synthetic pulp the fibrils of which are filled with an inorganic filler, the web incorporating a wetting agent which is preferably an organic sulphonate, and organic succinate, or a phenol ethoxylate.
Inventors
- 👤 David J. M. McCallum
- 👤 Alexander R. Clifford
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 06:02
CPC Classifications
D; D21; D21H; D21H5/00; D21H5/12; D21H5/20; H; H01; H01M; H01M50/00; H01M50/40; H01M50/489; Y; Y02; Y02E; Y02E60/00; Y02E60/10; Y10; Y10S; Y10S428/00; Y10S428/903; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2933; Y10T428/2964; Y10T428/2967; Y10T428/2969; Y10T428/2971
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
161 words
A battery separator made from a paper web formed from a furnish containing a pulp mixture of which between 60 and 80% by dry weight comprises a synthetic polypropylene wood pulp with a barium sulphate filler, and of which the balance of said pulp mixture is a bleached sulphate natural wood pulp, said furnish also containing polyester staple fibres at a level of between 5 and 20% by dry weight of said pulp mixture; and said web having a phenol ethoxylate wetting agent incorporated therein whereby said web has improved electrical resistance, even after accelereted ageing, so that the electrical resistance of said web after immersion for 20 minutes in battery acid is no more than 300 m.ohms cm 2 , and the wetting agent is retained in said web to such an extent that after accelerated ageing the electrical resistance of said web after immersion for 20 minutes in battery acid is no greater than 300 m.ohms cm 2 .
Claim 2
Dependent Claim
161 words
A battery separator made from a paper web formed from a furnish containing a pulp mixture of which between 60 and 80% by dry weight comprises a synthetic polypropylene wood pulp with a barium sulphate filler, and of which the balance of said pulp mixture is a bleached sulphate natural wood pulp, said furnish also containing polyester staple fibres at a level of between 5 and 20% by dry weight of said pulp mixture; and said web having a phenol ethoxylate wetting agent incorporated therein whereby said web has improved electrical resistance, even after accelereted ageing, so that the electrical resistance of said web after immersion for 20 minutes in battery acid is no more than 300 m.ohms cm 2 , and the wetting agent is retained in said web to such an extent that after accelerated ageing the electrical resistance of said web after immersion for 20 minutes in battery acid is no greater than 300 m.ohms cm 2 .
References Cited (Backward Citations)
US2531504A
Cited
US2482062A
Cited
US2872497A
Cited
GB836678A
Cited
GB873567A
Cited
GB941461A
Cited
GB948750A
Cited
GB1087635A
Cited
GB1116762A
Cited
US3329559A
Cited
US3351495A
Cited
GB1220461A
Cited
US3472700A
Cited
GB1230577A
Cited
US3524464A
Cited
US3811957A
Cited
US3907604A
Cited
GB1315471A
Cited
US3770856A
Cited
GB1386983A
Cited
GB1386982A
Cited
US4000967A
Cited
US3947537A
Cited
GB1362344A
Cited
GB1398623A
Cited
GB1412007A
Cited
GB1372115A
Cited
GB1392667A
Cited
US4060451A
Cited
GB1439514A
Cited
US3933525A
Cited
US3847676A
Cited
GB1461388A
Cited
GB1461389A
Cited
US3870567A
Cited
GB1423967A
Cited
GB1452807A
Cited
GB1443581A
Cited
GB1440737A
Cited
GB1457683A
Cited
US4010229A
Cited
GB1512997A
Cited
US4133797A
Cited
GB1523482A
Cited
GB1514530A
Cited
US4129629A
Cited
GB1520382A
Cited
US4152317A
Cited
US4158595A
Cited
US4157275A
Cited
US4146686A
Cited
US4245013A
Cited
US4216281A
Cited
US4279979A
Cited
US4264691A
Cited
US4277547A
Cited
US4298668A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-06-06 | 1986-12-06 | 1987-06-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-06-06 | 1990-12-06 | 1991-06-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-06-06 | 1994-12-06 | 1995-06-07 | $7700.00 | Window Closed / Lapsed |