US4539071A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Biocide
Assignee: Grace Dearborn Ltd
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Filing: 1983-04-18
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Granted: 1985-09-03
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Expires: 2003-04-18
Abstract
Abstract This invention relates to the elimination of bacterial deposits in cooling water systems and in water systems used in paper making. This is achieved by using a combination of glutaraldehyde and isothiazolone.
Inventors
- 👤 Richard P. Clifford
- 👤 Gerrard A. Birchall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 17:17
CPC Classifications
D; D21; D21C; D21C9/00; D21C9/008; A; A01; A01N; A01N43/00; A01N43/72; A01N43/80; C; C02; C02F; C02F1/00; C02F1/50
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
56 words
A method for the treatment of a cooling water system or of a water system used in paper making to inhibit baterial growth and slime formation which comprises adding to the water glutaraldehyde and isothiazolone in a weight ratio of isothiazolone to glutaraldehyde of from 1:1 to 1:10 in an amount sufficient to control bacterial growth.
Claim 2
Independent Claim
56 words
A method for the treatment of a cooling water system or of a water system used in paper making to inhibit baterial growth and slime formation which comprises adding to the water glutaraldehyde and isothiazolone in a weight ratio of isothiazolone to glutaraldehyde of from 1:1 to 1:10 in an amount sufficient to control bacterial growth.
Claim 3
Dependent Claim
20 words
A method according to claim 1 wherein the isothiazolone has the general formula: ##STR2## wherein R represents hydrogen or chlorine.
Claim 4
Dependent Claim
19 words
A method according to claim 1 wherein the weight ratio of isothiazolone to glutaraldehyde is from 1:3 to 1:5.
Claim 5
Dependent Claim
17 words
A method according to claim 3 wherein the weight ratio of isothiazolone to glutaraldehyde is about 1:4.
Claim 6
Dependent Claim
23 words
A method according to claim 1 which comprises adding from 0.05 to 1000 ppm of isothiazolone and 0.2 to 4000 ppm of glutaraldehyde.
Claim 7
Dependent Claim
22 words
A method according to claim 6 which comprises adding 0.25 to 50 ppm of isothiazolone and 1 to 200 ppm of glutaraldehyde.
Claim 8
Dependent Claim
15 words
A method according to claim 1 for the treatment of an industrial cooling water system.
Claim 9
Dependent Claim
24 words
A method according to claim 1 which comprises adding the glutaraldehyde and isothiazolone to a recirculating back water used for the paper pulping bath.
Claim 10
Dependent Claim
19 words
A method according to claim 1 which comprises adding the glutaraldehyde and isothiazolone directly to the paper pulping bath.
Claim 11
Dependent Claim
20 words
A method according to claim 1 which comprises adding the glutaraldehyde and isothiazolone to a holding tank containing moist pulp.
Claim 12
Dependent Claim
27 words
A method according to claim 1 which comprises adding the glutaraldehyde and isothiazolone in combination with a chemical additive which is added to the paper pulping bath.
Claim 13
Dependent Claim
34 words
A method according to claim 11 wherein the chemical additive is starch, titanium dioxide, a de-foamer, a size, a wet strength resin, a dispersant or retention aid, a filler or an optical brightening agent.
Claim 14
Dependent Claim
28 words
A biocide composition suitable for addition to an aqueous system which comprises isothiazolone and glutaraldehyde in a weight ratio of isothiazolone to glutaraldehyde of from 1:1 to 1:10.
Claim 15
Dependent Claim
28 words
A biocide composition suitable for addition to an aqueous system which comprises isothiazolone and glutaraldehyde in a weight ratio of isothiazolone to glutaraldehyde of from 1:1 to 1:10.
Claim 16
Dependent Claim
15 words
A composition according to claim 13 wherein the weight ratio is from 1:3 to 1:5.
Claim 17
Dependent Claim
13 words
A composition according to claim 14 wherein the weight ratio is from 1:4.
Claim 18
Dependent Claim
20 words
A composition according to claim 13 which contains from 1 to 15% by weight of isothiazolone and glutaraldehyde, taken together.
Claim 19
Dependent Claim
20 words
A composition according to claim 16 which contains from 7.5 to 12.5% by weight of isothiazolone and glutaraldehyde, taken together.
Claim 20
Dependent Claim
23 words
A composition according to claim 13 which is in the form of an aqueous solution optionally containing a stabilising agent for the isothiazolone.
Claim 21
Dependent Claim
17 words
A composition according to claim 13 which also contains a chemical additive for a paper pulping bath.
Claim 22
Dependent Claim
34 words
A composition according to claim 19 wherein the chemical additive is starch, titanium dioxide, a de-foamer, a size, a wet strength resin, a dispersant or retention aid, a filler or an optical brightening agent.
Claim 23
Dependent Claim
11 words
A composition according to claim 13 which also contains paper pulp.
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) | 1988-09-02 | 1989-03-04 | 1989-09-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-09-02 | 1993-03-04 | 1993-09-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-09-02 | 1997-03-04 | 1997-09-03 | $7700.00 | Window Closed / Lapsed |