US4283300A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and composition to inhibit staining of porcelain surfaces by manganese
Assignee: Procter and Gamble Co
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Filing: 1979-04-09
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Granted: 1981-08-11
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Expires: 1999-04-09
Abstract
Abstract Method and composition to inhibit the staining of water-contacting surfaces, such as those in a toilet bowl, which is caused by manganese present in household water in the presence of an oxidizing material. Manganese staining is inhibited by supplying to the water 0.1 to 10 ppm of a partially hydrolyzed polyacrylamide material. Compositions are also described in the context of an automatic toilet tank dispenser which provides sufficient quantities of the above material in solution to inhibit manganese staining of toilet bowl surfaces.
Inventors
- 👤 James L. Kurtz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:53
CPC Classifications
C; C02; C02F; C02F5/00; C02F5/08; C02F5/10
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
102 words
A method of inhibiting the staining of surfaces in contact with water which contains at least about 50 ppb of manganese II ions and an oxidizing agent which would oxidize said manganese (II) ions to form staining manganese (IV) ions; said method comprising the step of independently dispensing into said water which contains said manganese (II) ions and said oxidizing agent, from about 0.1 ppm to about 10 ppm of water-soluble, partially hydrolyzed polyacrylamide material having an average molecular weight of from 2000 to 10,000 atomic mass units, and wherein the polyacrylamide contains amide groups which were hydrolyzed to carboxylate/carboxylic acid moieties.
Claim 2
Independent Claim
102 words
A method of inhibiting the staining of surfaces in contact with water which contains at least about 50 ppb of manganese II ions and an oxidizing agent which would oxidize said manganese (II) ions to form staining manganese (IV) ions; said method comprising the step of independently dispensing into said water which contains said manganese (II) ions and said oxidizing agent, from about 0.1 ppm to about 10 ppm of water-soluble, partially hydrolyzed polyacrylamide material having an average molecular weight of from 2000 to 10,000 atomic mass units, and wherein the polyacrylamide contains amide groups which were hydrolyzed to carboxylate/carboxylic acid moieties.
Claim 3
Dependent Claim
18 words
The method of claim 1 whrein said oxidizing agent is further identified as a source of hypochlorite ions.
Claim 4
Dependent Claim
23 words
The method of claim 1 wherein said water-soluble, partially hydrolyzed polyacrylamide material has an average molecular weight of about 2000 atom mass units.
Claim 5
Dependent Claim
23 words
The method of claim 2 wherein 1 ppm to 5 ppm of said water-soluble, partially hydrolyzed polyacrylamide material are dispensed into said water.
Claim 6
Dependent Claim
16 words
The method of claim 4 wherein said water-soluble, partially hydrolyzed polyacrylamide material is approximately 80% hydrolyzed.
Claim 7
Dependent Claim
25 words
The method of claim 5 wherein about 3 ppm to about 4 ppm of said water-soluble, partially hydrolyzed polyacrylamide material are dispensed into said water.
Claim 8
Dependent Claim
21 words
The method of claim 2 wherein said oxidizing agent is independently and concurrently dispensed into said water from a separate source.
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) | 1984-08-10 | 1985-02-09 | 1985-08-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-08-10 | 1989-02-09 | 1989-08-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-08-10 | 1993-02-09 | 1993-08-11 | $7700.00 | Window Closed / Lapsed |