Patent US3568846A successfully refreshed from Google Patents.
US3568846A
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Plastic filter media
Assignee: North Carolina National Bank NCNB
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Filing: 1968-04-29
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Granted: 1971-03-09
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Expires: 1988-04-29
Abstract
Abstract An improved filter media is prepared by subjecting particles of a plastic material having discrete, irregular, nonuniform shaped surfaces to treatment with a quantity of a surfactant or wetting agent sufficient to permit the plastic particles to be readily wetted by water.
Inventors
- 👤 Albert J Haefner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 14:45
CPC Classifications
B; B01; B01D; B01D39/00; B01D39/02; B01D39/04; B01J; B01J20/00; B01J20/22; B01J20/26; B01J20/261; B01J20/28; B01J20/28002; B01J20/28004; B01J20/28014; B01J20/28016; B01J20/30; B01J20/32; B01J20/3202; B01J20/3206; B01J20/3208; B01J20/321; B01J20/3231; B01J20/3242; B01J20/3244; B01J20/3246; B01J20/3248; B01J20/3251; B01J20/3253
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
21 words
Filter media as defined in claim 1 wherein said polyvinyl chloride is produced by either emulsion, bulk, or suspension polymerization process.
Claim 2
Dependent Claim
22 words
Filter media as defined in claim 1 wherein the surfactant is selected from the group consisting of cationic, anionic, and nonionic surfactants.
Claim 3
Dependent Claim
14 words
Filter media as defined in claim 1 wherein the surfactant is sodium lauryl sulfate.
Claim 4
Dependent Claim
14 words
Filter media as defined in claim 1 wherein the surfactant is sodium dioctyl sulfosuccinate.
Claim 5
Dependent Claim
37 words
Filter media as defined in claim 1 wherein said polyvinyl chloride particles are treated with the surfactant in a concentration of from about 0.001 percent to about 1.0 percent weight based on the weight of said particles.
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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) | 1974-03-08 | 1974-09-07 | 1975-03-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-08 | 1978-09-07 | 1979-03-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-08 | 1982-09-07 | 1983-03-09 | $7700.00 | Window Closed / Lapsed |