Patent US4386005A successfully refreshed from Google Patents.
US4386005A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Scale inhibitor for reverse osmosis water purification system
Assignee: Goodrich Corp
•
Filing: 1981-01-06
•
Granted: 1983-05-31
•
Expires: 2001-01-06
Abstract
Abstract A composition for inhibiting scale build up in reverse osmosis water purification systems. The composition is composed of low molecular weight polyacrylic and phytic acid in a synergistic combination and significantly reduces build up of calcium, magnesium, and/or iron scale.
Inventors
- 👤 Anita G. Kapiloff
- 👤 Randolph T. Hatch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 12:58
CPC Classifications
C; C02; C02F; C02F5/00; C02F5/08; C02F5/10; C02F5/14; B; B01; B01D; B01D61/00; B01D61/02; B01D61/025; B01D61/04; B01D65/00; B01D65/08; B01D2311/00; B01D2311/04; B01D2321/00; B01D2321/16; B01D2321/162
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
68 words
A composition for inhibiting scale in a reverse osmosis water purification system consisting essentially of from 1 to 0.05 part by weight of polyacrylic acid having a molecular weight of from 1,000 to about 10,000 and from 0.05 to 1 part by weight of phytic acid to thereby provide from 0.01 to 20 ppm of each of said polyacrylic acid and said phytic acid when diluted for use.
Claim 2
Dependent Claim
68 words
A composition for inhibiting scale in a reverse osmosis water purification system consisting essentially of from 1 to 0.05 part by weight of polyacrylic acid having a molecular weight of from 1,000 to about 10,000 and from 0.05 to 1 part by weight of phytic acid to thereby provide from 0.01 to 20 ppm of each of said polyacrylic acid and said phytic acid when diluted for use.
Claim 3
Dependent Claim
27 words
A composition as claimed in claim 1, consisting essentially of 1 part by weight of said polyacrylic acid and 0.05 part by weight of said phytic acid.
Claim 4
Dependent Claim
20 words
A composition as claimed in claim 1, wherein said polyacrylic acid has a molecular weight of from 1,000 to 8,000.
Claim 5
Dependent Claim
20 words
A composition as claimed in claim 3, wherein said polyacrylic acid has a molecular weight of from 1,000 to 2,000.
Claim 6
Dependent Claim
22 words
A composition as claimed in claim 1, consisting essentially of equal amounts by weight of said polyacrylic acid and said phytic acid.
References Cited (Backward Citations)
US2497062A
Cited
US2626238A
Cited
US3502587A
Cited
US3549548A
Cited
US3589998A
Cited
US3890228A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-05-30 | 1986-11-29 | 1987-05-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-05-30 | 1990-11-29 | 1991-05-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-05-30 | 1994-11-29 | 1995-05-31 | $7700.00 | Window Closed / Lapsed |