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US3954652A
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Bleaching agent
Assignee: BASF SE
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Filing: 1973-08-29
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Granted: 1976-05-04
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Expires: 1993-08-29
Abstract
Abstract Reductive bleaching agents which contain alkali metal sulfites and zinc oxide or soluble zinc salts.
Inventors
- 👤 Oswald Schmidt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 02:47
CPC Classifications
D; D06; D06L; D06L4/00; D06L4/30
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
71 words
A reductive bleaching agent comprising a mixture of a. 60 to 95% by weight of a sulfur compound in the +4 oxidation state selected from the group consisting of alkali metal bisulfites and pyrosulfite; and b. 40 to 5% by weight of a zinc compound selected from the group consisting of zinc oxide and soluble zinc salts, the percentages being with reference to the total weight of the dry bleaching agent.
Claim 2
Dependent Claim
71 words
A reductive bleaching agent comprising a mixture of a. 60 to 95% by weight of a sulfur compound in the +4 oxidation state selected from the group consisting of alkali metal bisulfites and pyrosulfite; and b. 40 to 5% by weight of a zinc compound selected from the group consisting of zinc oxide and soluble zinc salts, the percentages being with reference to the total weight of the dry bleaching agent.
Claim 3
Dependent Claim
42 words
A reductive bleaching agent as claimed in claim 1, wherein a part of the alkali metal bisulfite and/or pyrosulfite is replaced by a bleaching compound selected from the group consisting of alkali metal dithionites and alkali metal zinc salts of hydroxymethanesulfinic acid.
Claim 4
Dependent Claim
43 words
A reductive bleaching agent as claimed in claim 1, which contains from 15 to 35% by weight with reference to the dry bleaching agent, of a bleaching compound selected from the group consisting of alkali metal dithionites and alkali metal and zinc hydroxymethanesulfinates.
Claim 5
Dependent Claim
80 words
A strongly acidic aqueous bleaching liquor containing, as a reductive bleaching agent, a mixture consisting essentially of a. 60 to 95% by weight of a sulfur compound in the +4 oxidation state selected from the group consisting of alkali metal bisulfites and pyrosulfite; and b. 40 to 5% by weight of a zinc compound selected from the group consisting of zinc oxide and soluble zinc salts, the percentages being with reference to the total weight of the dry bleaching agent.
Claim 6
Dependent Claim
80 words
A strongly acidic aqueous bleaching liquor containing, as a reductive bleaching agent, a mixture consisting essentially of a. 60 to 95% by weight of a sulfur compound in the +4 oxidation state selected from the group consisting of alkali metal bisulfites and pyrosulfite; and b. 40 to 5% by weight of a zinc compound selected from the group consisting of zinc oxide and soluble zinc salts, the percentages being with reference to the total weight of the dry bleaching agent.
Claim 7
Dependent Claim
28 words
A reductive bleaching agent as claimed in claim 1 having a proportion of 65 to 90% by weight of (a) to 35 to 10% by weight of (b).
Claim 8
Dependent Claim
16 words
The bleaching liquor as claimed in claim 4 having a pH of less than about 5.5.
Claim 9
Dependent Claim
27 words
The bleaching liquor as claimed in claim 6 having a proportion of 65 to 90% by weight of (a) to 35 to 10% by weight of (b).
Claim 10
Dependent Claim
16 words
The bleaching liquor as claimed in claim 4 having a pH of about 3.5 to 5.
Claim 11
Dependent Claim
27 words
The bleaching liquor as claimed in claim 8 having a proportion of 65 to 90% by weight of (a) to 35 to 10% by weight of (b).
Claim 12
Dependent Claim
41 words
The bleaching liquor as claimed in claim 9 wherein a part of the alkali metal bisulfite and/or pyrosulfite is replaced by a bleaching compound selected from the group consisting of alkali metal dithionites and alkali metal zinc salts of hydroxymethanesulfinic acid.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-05-04 | 1979-11-03 | 1980-05-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-05-04 | 1983-11-03 | 1984-05-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-05-04 | 1987-11-03 | 1988-05-04 | $7700.00 | Window Closed / Lapsed |