US3158532A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tapered pore filter elements
Assignee: Pall Corp
•
Filing: 1960-12-06
•
Granted: 1964-11-24
•
Expires: 1980-12-06
Abstract
No abstract record available.
Inventors
- 👤 David B Pall
- 👤 Cyril A Keedwell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 09:50
CPC Classifications
B; B01; B01D; B01D39/00; B01D39/14; B01D39/20; B01D39/2003; B01D39/2006; B01D39/2013; B01D39/2017; B01D39/2024; B01D39/2068; B01D39/2072; B01D39/2079; B01D39/2082; B01D39/2089
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
90 words
A PROCESS FOR PREPARING POROUS DEPTH FILTERS HAVING PORES WHICH VARY IN DIAMETER AND CONFIGURATION FROM SURFACE TO SURFACE OF THE MATERIAL, COMPRISING BLENDING CONTINUOUSLY AT LEAST TWO SEPARATE SUSPENSION COMPRISING PARTICULATE MATERIAL SUSPENDED IN A FLUID, THE SEPARATE SUSPENSIONS SEVERALLY COMPRISING PARTICULATE MATERIAL OF DIFFERENT SIZES WHILE VARYING THE PROPORTIONS BLENDED OF PARTICULATE MATERIAL OF EACH SIZE SEQUENTIALLY, AND DEPOSITING THE MIXTURE THUS PRODUCED UPON A BASE TO FORM A POROUS MATERIAL, THEREBY PRODUCING A MATERIAL HAVING A PORE DIAMETER AND PORE CONFIGURATION VARYING FROM SURFACE TO SURFACE THEREOF.
Claim 2
Dependent Claim
90 words
A PROCESS FOR PREPARING POROUS DEPTH FILTERS HAVING PORES WHICH VARY IN DIAMETER AND CONFIGURATION FROM SURFACE TO SURFACE OF THE MATERIAL, COMPRISING BLENDING CONTINUOUSLY AT LEAST TWO SEPARATE SUSPENSION COMPRISING PARTICULATE MATERIAL SUSPENDED IN A FLUID, THE SEPARATE SUSPENSIONS SEVERALLY COMPRISING PARTICULATE MATERIAL OF DIFFERENT SIZES WHILE VARYING THE PROPORTIONS BLENDED OF PARTICULATE MATERIAL OF EACH SIZE SEQUENTIALLY, AND DEPOSITING THE MIXTURE THUS PRODUCED UPON A BASE TO FORM A POROUS MATERIAL, THEREBY PRODUCING A MATERIAL HAVING A PORE DIAMETER AND PORE CONFIGURATION VARYING FROM SURFACE TO SURFACE THEREOF.
References Cited (Backward Citations)
US1672988A
Cited
US1921504A
Cited
US2371313A
Cited
US2372437A
Cited
US2414833A
Cited
US2503454A
Cited
US2517753A
Cited
US2539768A
Cited
US2708982A
Cited
US2698972A
Cited
US2919211A
Cited
US2971907A
Cited
US2928765A
Cited
FR1236747A
Cited
US3039914A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1967-11-24 | 1968-05-25 | 1968-11-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-11-24 | 1972-05-25 | 1972-11-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-11-24 | 1976-05-25 | 1976-11-24 | $7700.00 | Window Closed / Lapsed |