US3720574A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Filter element
Assignee: Kimberly Clark Tissue Co
•
Filing: 1971-07-28
•
Granted: 1973-03-13
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Expires: 1991-07-28
Abstract
Abstract A flexible, reticulated, polyurethane foam which has been rigidified by coating the strands with an epoxy resin is especially useful as a filter element due to the unexpected increase in dirt holding capacity of the rigidified foam as compared to the flexible, untreated foam.
Inventors
- 👤 F Kunc
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 02:51
CPC Classifications
B; B01; B01D; B01D39/00; B01D39/14; B01D39/16; B01D39/1669; B01D39/1676; B32; B32B; B32B5/00; B32B5/22; B32B5/32; B32B5/18; C; C08; C08J; C08J9/00; C08J9/36; C08J9/40; C08J9/42; B32B2266/00; B32B2266/02; B32B2266/0214; B32B2266/0278; C08J2375/00; C08J2375/04; C08J2463/00; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24479; Y10T428/24496; Y10T428/24504; Y10T428/24512; Y10T428/249921; Y10T428/249953; Y10T428/249962; Y10T428/249964; Y10T428/249981
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
21 words
A self-supporting filter element comprising a reticulated polyurethane foam the strands of said foam being coated with a cured epoxy resin.
Claim 2
Dependent Claim
21 words
A self-supporting filter element comprising a reticulated polyurethane foam the strands of said foam being coated with a cured epoxy resin.
Claim 3
Dependent Claim
28 words
A self-supporting filter element, as claimed in claim 1, in which the reticulated polyurethane foam is a foam composite comprising two layers of reticulated polyurethane foam bonded together.
Claim 4
Dependent Claim
28 words
A self-supporting filter element, as claimed in claim 1, in which the resin coating also includes the reaction product of an epoxy-containing resin and a halogen-containing hydroxyl compound.
References Cited (Backward Citations)
US3269887A
Cited
US3314425A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-03-12 | 1976-09-11 | 1977-03-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-12 | 1980-09-11 | 1981-03-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-12 | 1984-09-11 | 1985-03-13 | $7700.00 | Window Closed / Lapsed |