Claims
- 1. An aqueous pumpable fire-fighting concentrate for dilution with at least about ten times its volume of water and foaming with air to produce a fire-fighting foam having an expansion of at least about 3, the concentrate consisting essentially of water having dissolved therein a foaming agent that provides the foamability, and a thixotropic polysaccharide thickener that increases the Brookfield spindle 4 viscosity of the concentrate at 20.degree. C. to not over about 3,000 centipoises at 60 rpm spindle speed and causes the fire-fighting foam to form an insoluble gel blanket when placed on a burning hydrophilic liquid, the concentration of the thickener in the concentrate being at least about 1% by weight.
- 2. The concentrate of claim 1 in which the polysaccharide is a degraded heteropolysaccharide-7.
- 3. The process of fighting a fire on a body of hydrophilic liquid, which process comprises applying to the burning surface of that liquid a foam having an expansion of at least about 3 foamed from an aqueous solution of a foaming agent and thixotropic polysaccharide selected from the class consisting of heteropolysaccharide-7 and degraded forms of heteropolysaccharide-7, the polysaccharide being dissolved in that solution in an amount that causes the foam to form a gel blanket when it contacts the hydrophilic liquid, and the solution being essentially in sea water.
- 4. The concentrate of claim 1 in which the concentration of the polysaccharide is over 1.1% by weight.
- 5. The concentrate of claim 1 in which the polysaccharide is selectd from the class consisting of heteropolysaccharide-7 and degraded forms of heteropolysaccharide-7, and the concentrate also contains magnesium sulfate dissolved in a proportion at least about 1/6 the weight of the polysaccharide and sufficient to improve the fire-fighting effectiveness of the concentrate when it is diluted with fresh water.
Parent Case Info
This application is a continuation-in-part of applications Ser. No. 670,252 filed Mar. 25, 1976 (U.S. Pat. No. 4,060,489 granted Nov. 29, 1977), Ser. No. 557,757 filed Mar. 12, 1975 (U.S. Pat. No. 4,060,132 granted Nov. 29, 1977) and Ser. No. 525,175 filed Nov. 19, 1974 (U.S. Patent No. 4,038,195 granted July 26, 1977), each of which is in turn a continuation-in-part of prior application Ser. No. 369,584 filed June 13, 1973 (U.S Pat. No. 3,957,659 granted May 18, 1976). Applications Ser. Nos. 557,757, 525,175 and 369,584 are also continuations-in-part of earlier application Ser. No. 307,479 filed Nov. 17, 1972 (subsequently abandoned); while applications Ser. Nos. 525,175, 369,584 and 307,479 are each continuations-in-part of still earlier application Ser. No. 254,404 filed May 18, 1972 (U.S. Pat. No. 3,849,315 granted Nov. 19, 1974); and applications Ser. Nos. 369,584, 307,479 and 254,404 are each continuations-in-part of parent application Ser. No. 131,763 filed Apr. 6, 1971 (subsequently abandoned).
US Referenced Citations (8)
Non-Patent Literature Citations (1)
Entry |
Howard, R. D., Research Disclosure, No. 122, pp. 47-48 (Jun. 1974). |
Related Publications (8)
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Date |
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557757 |
Mar 1975 |
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525175 |
Nov 1974 |
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525175 |
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369584 |
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369584 |
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307479 |
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307479 |
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254404 |
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Continuation in Parts (5)
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Number |
Date |
Country |
Parent |
670252 |
Mar 1976 |
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Parent |
369584 |
Jun 1973 |
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Parent |
307479 |
Nov 1972 |
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Parent |
254404 |
May 1972 |
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Parent |
131763 |
Apr 1971 |
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