# US 12,214,236 B2 · Long-term fire retardant with corrosion inhibitors and methods for making and using same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,214,236 B2 - Document ID: US12214236B2 - Status: Granted - Kind: B2 - Application number: 18/404,027 - Filed: 2024-01-04 - Published: 2024-05-02 - Granted: 2025-02-04 - Earliest claimed: 2020-12-15 - Assignees: FRS Group, LLC - Applicants: FRS Group, LLC - Inventors: Dennis Hulbert; Robert J. Burnham; Michael S. Schnarr; Gerald Geissler; David W. Wilkening; Joseph McLellan; Michael White - Web page: https://patentgrep.com/patent/US12214236B2 ## CPC - A62D 1/005: {Dispersions; Emulsions} - A62C 3/02: for area conflagrations, e.g. forest fires, subterranean fires - A62D 1/0007: {Solid extinguishing substances} - A62D 1/0035: {Aqueous solutions} - C01F 5/40: Magnesium sulfates (double sulfates of magnesium with sodium or potassium C01D5/12, with other alkali metals {C01D15/00}, C01D17/00) - C09K 21/04: containing phosphorus - A62D: CHEMICAL MEANS FOR EXTINGUISHING FIRES OR FOR COMBATING OR PROTECTING AGAINST HARMFUL CHEMICAL AGENTS; CHEMICAL MATERIALS FOR USE IN BREATHING APPARATUS - A62C: FIRE-FIGHTING (fire-extinguishing compositions, use of chemical substances in extinguishing fires A62D1/00; spraying, applying liquids or other fluent materials to surfaces in general B05; alarm arrangements G08B, e.g. fire alarms actuated by smoke or gases G08B17/10) - C01F: COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS (metal hydrides {monoborane, diborane or addition complexes thereof} C01B6/00; salts of oxyacids of halogens C01B11/00; peroxides, salts of peroxyacids C01B15/00; sulfides or polysulfides of magnesium, calcium, strontium, or barium C01B17/42; thiosulfates, dithionites, polythionates C01B17/64; compounds containing selenium or tellurium C01B19/00; binary compounds of nitrogen with metals C01B21/06; azides C01B21/08; {compounds other than ammonia or cyanogen containing nitrogen and non-metals and optionally metals C01B21/082; amides or imides of silicon C01B21/087}; metal {imides or} amides C01B21/092, {C01B21/0923}; nitrites C01B21/50; {compounds of noble gases C01B23/0005}; phosphides C01B25/08; salts of oxyacids of phosphorus C01B25/16; carbides C01B32/90; compounds containing silicon C01B33/00; compounds containing boron C01B35/00; compounds having molecular sieve properties but not having base-exchange properties C01B37/00; compounds having molecular sieve and base-exchange properties, e.g. crystalline zeolites, C01B39/00; cyanides C01C3/08; salts of cyanic acid C01C3/14; salts of cyanamide C01C3/16; thiocyanates C01C3/20; {double sulfates of magnesium with sodium or potassium C01D5/12; with other alkali metals C01D15/00, C01D17/00}) - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE ## Abstract A forest fire retardant composition contains a retardant compound that includes a phosphate salt. The phosphate salt may include diammonium phosphate, diammonium orthophosphate, monoammonium phosphate, monoammonium orthophosphate, monosodium phosphate, disodium phosphate, disodium phosphate hydrate, sodium ammonium phosphate, sodium ammonium phosphate hydrate, sodium tripolyphosphate, trisodium phosphate, or dipotassium phosphate, and combinations thereof. The forest fire retardant composition may include an ammonium source. The composition may be in the form of a dry concentrate, a liquid concentrate, or a final diluted product. The final diluted product is effective in suppressing, retarding, and controlling forest fires while exhibiting corrosion resistance and low toxicity. ## Claims ### Claim 1 A forest fire retardant concentrate, comprising: a mixture of phosphates comprising: diammonium phosphate; monoammonium phosphate; and at least one of a sodium phosphate salt, a calcium phosphate salt, or a potassium phosphate salt; a corrosion inhibitor for at least one of steel, brass, aluminum, or magnesium, present in the concentrate in an amount having a weight percent of about 0.1% to about 3.0% relative to total weight of the concentrate; and a thickening agent, present in the concentrate in an amount having a weight percent of about 0.75% to about 5.0% relative to total weight of the concentrate. ### Claim 2 (depends on 1) The concentrate of claim 1, wherein the concentrate has a molar ratio of ammoniacal nitrogen to phosphorus (N/P molar ratio) of less than about 1.4. ### Claim 3 (depends on 2) The concentrate of claim 2, wherein the concentrate has a molar ratio of ammoniacal nitrogen to phosphorus (N/P molar ratio) of less than about 1.3. ### Claim 4 (depends on 3) The concentrate of claim 3, wherein the concentrate has a molar ratio of ammoniacal nitrogen to phosphorus (N/P molar ratio) of less than about 1.1. ### Claim 5 (depends on 1) The concentrate of claim 1, wherein the sodium phosphate salt, the calcium phosphate salt, or the potassium phosphate salt comprises at least one of monosodium phosphate, disodium phosphate, disodium phosphate hydrate, sodium ammonium phosphate, sodium ammonium phosphate hydrate, sodium tripolyphosphate, trisodium phosphate, monocalcium phosphate, dicalcium phosphate, tricalcium phosphate, octacalcium phosphate, dicalcium diphosphate, calcium triphosphate, hydroxyapatite, apatite, tetracalcium phosphate, monopotassium phosphate, dipotassium phosphate, or tripotassium phosphate. ### Claim 6 (depends on 1) The concentrate of claim 1, wherein the corrosion inhibitor comprises at least one of: an alkyl amine; one or more azoles; or disodium molybdate dihydrate. ### Claim 7 (depends on 1) The concentrate of claim 1, wherein the thickening agent comprises at least one of a polyurethane, a polyvinyl alcohol, an acrylic polymer, a gum, a cellulosic, a sulfonate, a saccharide, a clay, an organosilicone, or a protein. ### Claim 8 (depends on 7) The concentrate of claim 7, wherein the thickening agent comprises the gum. ### Claim 9 (depends on 8) The concentrate of claim 8, wherein the gum comprises a polysaccharide gum. ### Claim 10 (depends on 1) The concentrate of claim 1, further comprising a colorant, present in the concentrate in an amount having a weight percent of about 0.04% to about 6.0% relative to total weight of the concentrate. ### Claim 11 (depends on 10) The concentrate of claim 10, wherein the colorant comprises an inorganic pigment and an organic pigment. ### Claim 12 (depends on 11) The concentrate of claim 11, wherein the organic pigment comprises a fluorescent pigment. ### Claim 13 (depends on 11) The concentrate of claim 11, wherein the inorganic pigment comprises iron oxide. ### Claim 14 (depends on 1) The concentrate of claim 1, further comprising a buffering agent present in the concentrate in an amount having a weight percent of about 2% to about 58% relative to the total weight of the concentrate. ### Claim 15 (depends on 1) The concentrate of claim 1, wherein: the concentrate is a dry concentrate having no more than about 3% by weight of water relative to the total weight of the dry concentrate; and the mixture of phosphates is present in the dry concentrate in an amount having a weight percent of about 62% to about 99% relative to the total weight of the dry concentrate. ### Claim 16 (depends on 1) The concentrate of claim 1, wherein: the concentrate is a liquid concentrate further comprising water; and the mixture of phosphates is present in the liquid concentrate in an amount having a weight percent of about 30% to about 80% relative to the total weight of the liquid concentrate. ### Claim 17 (depends on 1) A final diluted product formed by diluting the concentrate of claim 1 with water; wherein: the final diluted product is intended for use to suppress, retard, or contain forest fires; the mixture of phosphates is present in the final diluted product in an amount having a weight percent of about 6% to about 28% relative to the total weight of the final diluted product; and the final diluted product has a pH of about 5.0 to about 7.0. ### Claim 18 A forest fire retardant concentrate, comprising: a mixture of phosphates comprising: at least one ammonium phosphate salt; and at least one of a sodium phosphate salt, a calcium phosphate salt, or a potassium phosphate salt; a corrosion inhibitor for at least one of steel, brass, aluminum, or magnesium, present in the concentrate in an amount having a weight percent of about 0.1% to about 3.0% relative to total weight of the concentrate; and guar gum, present in the concentrate in an amount having a weight percent of about 0.75% to about 5.0% relative to total weight of the concentrate. ### Claim 19 (depends on 18) The concentrate of claim 18, wherein the at least one ammonium phosphate comprises at least one of diammonium phosphate, diammonium orthophosphate, monoammonium phosphate, monoammonium orthophosphate, or ammonium polyphosphate. ### Claim 20 (depends on 18) The concentrate of claim 18, wherein the at least one sodium phosphate salt, the calcium phosphate salt, or the potassium phosphate salt comprises at least one of monosodium phosphate, disodium phosphate, disodium phosphate hydrate, sodium ammonium phosphate, sodium ammonium phosphate hydrate, sodium tripolyphosphate, trisodium phosphate, monocalcium phosphate, dicalcium phosphate, tricalcium phosphate, octacalcium phosphate, dicalcium diphosphate, calcium triphosphate, hydroxyapatite, apatite, tetracalcium phosphate, monopotassium phosphate, dipotassium phosphate, or tripotassium phosphate. ### Claim 21 (depends on 18) The concentrate of claim 18, wherein the corrosion inhibitor comprises at least one of: an alkyl amine; one or more azoles; or disodium molybdate dihydrate. ### Claim 22 (depends on 18) The concentrate of claim 18, further comprising a colorant, present in the concentrate in an amount having a weight percent of about 0.04% to about 6.0% relative to total weight of the concentrate. ### Claim 23 (depends on 22) The concentrate of claim 22, wherein the colorant comprises an inorganic pigment and an organic pigment. ### Claim 24 (depends on 23) The concentrate of claim 23, wherein the organic pigment comprises a fluorescent pigment. ### Claim 25 (depends on 23) The concentrate of claim 23, wherein the inorganic pigment comprises iron oxide. ### Claim 26 (depends on 18) The concentrate of claim 18, further comprising a buffering agent present in the concentrate in an amount having a weight percent of about 2% to about 58% relative to the total weight of the concentrate. ### Claim 27 (depends on 18) The concentrate of claim 18, wherein the concentrate has a molar ratio of ammoniacal nitrogen to phosphorus (N/P molar ratio) of less than about 1.4 or greater than about 1.9. ### Claim 28 (depends on 18) The concentrate of claim 18, wherein: the concentrate is a dry concentrate having no more than about 3% by weight of water relative to the total weight of the dry concentrate; and the mixture of phosphates is present in the dry concentrate in an amount having a weight percent of about 60% to about 99.5% relative to the total weight of the dry concentrate. ### Claim 29 (depends on 18) The concentrate of claim 18, wherein: the concentrate is a liquid concentrate further comprising water; and the mixture of phosphates is present in the liquid concentrate in an amount having a weight percent of about 30% to about 80% relative to the total weight of the liquid concentrate. ### Claim 30 (depends on 18) A final diluted product formed by diluting the concentrate of claim 18 with water; wherein: the final diluted product is intended for use to suppress, retard, or contain forest fires; the mixture of phosphates is present in the final diluted product in an amount having a weight percent of about 4% to about 30% relative to the total weight of the final diluted product; and the final diluted product has a pH of about 5.0 to about 7.0.