US4594158A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Filter aid materials bearing anion exchange resins
Assignee: Rohm and Haas Co
•
Filing: 1981-09-03
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Granted: 1986-06-10
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Expires: 2001-09-03
Abstract
Abstract Conventional filter aid materials are treated with anion exchange resin materials having particle diameters smaller than 1 micrometer to produce an improved filter aid material bearing a fixed monolayer of the anion exchange resins.
Inventors
- 👤 Berni P. Chong
- 👤 Eric G. Isacoff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 05:44
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/02; B01J20/10; B01J20/103; B01J20/106; B01D; B01D37/00; B01D37/02; B01J20/28; B01J20/28002; B01J20/28004; B01J20/28014; B01J20/28023; B01J20/30; B01J20/32; B01J20/3202; B01J20/3204; B01J20/3206; B01J20/3208; B01J20/321; B01J20/3212; B01J20/3214; B01J20/3217; B01J20/3221; B01J20/3231; B01J20/3242; B01J20/3268; B01J20/327; B01J47/00; B01J47/12; B01J47/133; C; C02; C02F; C02F1/00; C02F1/42
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
61 words
An improved filter comprising as a precoat layer a floc of finely divided anion exchange resin and cation exchange resin, and an overcoat layer deposited thereon, the overcoat layer comprising a filter aid and coated irremovably upon the surface thereof, by electrostatic bonding, finely divided anion exchange resin particles having an average particle diameter between about 0.05 and about 1 micrometer.
Claim 2
Dependent Claim
61 words
An improved filter comprising as a precoat layer a floc of finely divided anion exchange resin and cation exchange resin, and an overcoat layer deposited thereon, the overcoat layer comprising a filter aid and coated irremovably upon the surface thereof, by electrostatic bonding, finely divided anion exchange resin particles having an average particle diameter between about 0.05 and about 1 micrometer.
Claim 3
Dependent Claim
28 words
The improved filter of claim 1 wherein the anion exchange resin particles bonded to the filter aid have a particle diameter between about 0.05 and about 0.2 micrometers.
Claim 4
Dependent Claim
29 words
The improved filter of claim 1 wherein the filter aid is selected from the group consisting of cellulose fibers, asbestos fibers, polyacrilonitrile fibers, charcoal, diatomaceous earth and expanded perlite.
Claim 5
Dependent Claim
13 words
The improved filter of claim 3 wherein the filter aid is polyacrilonitrile fibers.
Claim 6
Dependent Claim
13 words
The improved filter of claim 3 wherein the filter aid is cellulose fibers.
Claim 7
Independent Claim
62 words
A method of preparing an improved filter aid composition which comprises mixing in aqueous suspension a filter aid with anion exchange resin particles having a diameter of from about 0.05 to about 1 micrometer until the particles have become irremovably bound to the surface of the filter aid, and thereafter removing any unbonded anion exchange resin particles from the filter aid composition.
Claim 8
Independent Claim
62 words
A method of preparing an improved filter aid composition which comprises mixing in aqueous suspension a filter aid with anion exchange resin particles having a diameter of from about 0.05 to about 1 micrometer until the particles have become irremovably bound to the surface of the filter aid, and thereafter removing any unbonded anion exchange resin particles from the filter aid composition.
Claim 9
Dependent Claim
24 words
The method of claim 6 wherein the amount of anion exchange resin particles deposited is sufficient to saturate the surface of the filter aid.
Claim 10
Dependent Claim
18 words
The method of claim 6 wherein the resin particle diameter is from about 0.05 to about 0.2 micrometers.
References Cited (Backward Citations)
US4187120A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-06-09 | 1989-12-09 | 1990-06-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-06-09 | 1993-12-09 | 1994-06-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-06-09 | 1997-12-09 | 1998-06-10 | $7700.00 | Window Closed / Lapsed |