US4007113A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Particulate filter medium and process
Assignee: Specialty Materials Inc
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Filing: 1975-07-22
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Granted: 1977-02-08
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Expires: 1995-07-22
Abstract
Abstract Improved filter media comprised of negatively charged high surface area particulate filter material the surface of which is modified with a melamine-formaldehyde cationic colloid; processes for the preparation thereof; and use in liquid filtration to remove submicron contaminants including negatively charged particles.
Inventors
- 👤 Eugene A. Ostreicher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:41
CPC Classifications
B; B01; B01D; B01D69/00; B01D69/14; B01D69/141; B01D69/1411; B01D36/00; B01D36/003; B01D39/00; B01D39/02; B01D39/14; B01D39/16; B01D39/1607; B01D39/1623; B01D39/163; B01D39/18; B01D39/20; B01D39/2003; B01D39/2017; B01D2239/00; B01D2239/04; B01D2239/0471; B01D2239/0478; B01D2239/0492; B01D2239/12; B01D2239/1233; B01D2239/1241
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
25 words
An improved filter medium consisting essentially of a matrix of self-bonding fibers, and diatomaceous earth, the surface of which is modified with melamine-formaldehyde cationic colloid.
Claim 2
Dependent Claim
25 words
An improved filter medium consisting essentially of a matrix of self-bonding fibers, and diatomaceous earth, the surface of which is modified with melamine-formaldehyde cationic colloid.
Claim 3
Dependent Claim
38 words
An improved filter medium consisting essentially of a matrix of self-bonding fibers, and perlite, the surface of which is modified with melamine-formaldehyde cationic colloid, said perlite having a cake density of less than about 20 lbs./ft/ 3 .
Claim 4
Dependent Claim
38 words
An improved filter medium consisting essentially of a matrix of self-bonding fibers, and perlite, the surface of which is modified with melamine-formaldehyde cationic colloid, said perlite having a cake density of less than about 20 lbs./ft/ 3 .
Claim 5
Dependent Claim
29 words
An improved filter medium of enhanced electrokinetic capture potential for contaminated liquids comprising suspended electronegative particles of about 0.1 to 0.7 micron diameter, said filter medium consisting essentially of
Claim 6
Dependent Claim
29 words
An improved filter medium of enhanced electrokinetic capture potential for contaminated liquids comprising suspended electronegative particles of about 0.1 to 0.7 micron diameter, said filter medium consisting essentially of
Claim 7
Dependent Claim
29 words
high surface area electronegative particulate filter material, the electric (zeta) potential of the surface of which is modified with melamine-formaldehyde cationic colloid; and 2. a matrix of self-bonding fibers.
Claim 8
Dependent Claim
29 words
high surface area electronegative particulate filter material, the electric (zeta) potential of the surface of which is modified with melamine-formaldehyde cationic colloid; and 2. a matrix of self-bonding fibers.
Claim 9
Dependent Claim
25 words
The improved filter medium of claim 3, wherein said self-bonding fibers are comprised of cellulose, and the surface of said particulate filter material is electropositive.
Claim 10
Dependent Claim
33 words
A process for the filtration of contaminated liquids comprising suspended electronegative particles of about 0.1 to 0.7 micron diameter, said process comprising passing said contaminated liquid through the filter medium of claim 3.
References Cited (Backward Citations)
US3158532A
Cited
US3238056A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-02-08 | 1980-08-09 | 1981-02-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-02-08 | 1984-08-09 | 1985-02-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-02-08 | 1988-08-09 | 1989-02-08 | $7700.00 | Window Closed / Lapsed |