US3883640A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sodium percarbonate crystals
Assignee: Imperial Chemical Industries Ltd
•
Filing: 1973-01-15
•
Granted: 1975-05-13
•
Expires: 1993-01-15
Abstract
Abstract Sodium percarbonate is obtained by adding to the reaction mixture organic polyelectrolytes to improve the particle size and chemical stability of the crystals.
Inventors
- 👤 James Crosby Smart
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 14:15
CPC Classifications
C; C01; C01B; C01B15/00
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
58 words
IN A PROCESS FOR THE PREPARATION OF SODIUM PERCARBONATE CRYSTALS FROM AN AQUEOUS SOLUTION OF SODIUM PERCARBONATE, THE IMPROVEMENT WHICH COMPRISES INCORPORATING IN THE SAID AQUEOUS SOLUTION A WATER SOLUBLE ACRYLIC POLYMER POLYELECTROLYTE THE CONCENTRATION OF SAID POLYELECTROLYTE BEING BETWEEN 10 AND 10,000 PARTS PER MILLION BY WEIGHT OF SODIUM PERCARBONATE TO BE CRYSTALLIZED FROM THE SAID SOLUTION.
Claim 2
Dependent Claim
58 words
IN A PROCESS FOR THE PREPARATION OF SODIUM PERCARBONATE CRYSTALS FROM AN AQUEOUS SOLUTION OF SODIUM PERCARBONATE, THE IMPROVEMENT WHICH COMPRISES INCORPORATING IN THE SAID AQUEOUS SOLUTION A WATER SOLUBLE ACRYLIC POLYMER POLYELECTROLYTE THE CONCENTRATION OF SAID POLYELECTROLYTE BEING BETWEEN 10 AND 10,000 PARTS PER MILLION BY WEIGHT OF SODIUM PERCARBONATE TO BE CRYSTALLIZED FROM THE SAID SOLUTION.
Claim 3
Dependent Claim
28 words
The process according to claim 1 wherein the acrylic polymer is selected from the group consisting of polymers and copolymers of acrylic and methacrylic acids and salts thereof.
References Cited (Backward Citations)
US1237128A
Cited
US2120430A
Cited
US2863835A
Cited
US3109706A
Cited
US3677697A
Cited
US3770390A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-05-12 | 1978-11-11 | 1979-05-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-12 | 1982-11-11 | 1983-05-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-12 | 1986-11-11 | 1987-05-13 | $7700.00 | Window Closed / Lapsed |