# US 10,369,395 B2 · Trimethylglycine as a freeze suppressant in fire fighting foams > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,369,395 B2 - Document ID: US10369395B2 - Status: Granted - Kind: B2 - Application number: 14/775,622 - Filed: 2014-03-14 - Published: 2016-02-11 - Granted: 2019-08-06 - Earliest claimed: 2013-03-14 - Assignees: Tyco Fire Products LP - Applicants: Tyco Fire Products LP - Inventors: Martina E. Bowen; Mark Adam-Christopher Siem; Stephen Aloysius Barker - Web page: https://patentgrep.com/patent/US10369395B2 ## CPC - A62D 1/0085: {containing perfluoroalkyl-terminated surfactant} - A62D 1/0071: {Foams} - A62D: CHEMICAL MEANS FOR EXTINGUISHING FIRES OR FOR COMBATING OR PROTECTING AGAINST HARMFUL CHEMICAL AGENTS; CHEMICAL MATERIALS FOR USE IN BREATHING APPARATUS ## Abstract Fire foam concentrates are provided that contain trimethyl glycine as a freeze suppressant, an effective amount of at least one anionic, zwitterionic or nonionic surfactant, and an effective amount of a foam stabilizing agent. Methods of preparing fire fighting foams from the concentrates, and methods of fighting fires using these foams, also are provided. ## Claims ### Claim 1 A fire-fighting foam comprising: (a) 0.25 wt %-3.6 wt % trimethyl glycine; (b) at least one surfactant selected from the group consisting of anionic, zwitterionic and nonionic surfactants; (c) a foam stabilizing agent; and (d) an aqueous liquid; wherein the fire-fighting foam is formed by foaming an aqueous firefighting foam concentrate that has been diluted with the aqueous liquid; and the aqueous firefighting foam concentrate contains the trimethyl glycine in an amount that is effective to depress the freezing point of said concentrate below 0° C. ### Claim 2 (depends on 1) The fire-fighting foam according to claim 1, wherein said aqueous liquid is made from brackish water or seawater. ### Claim 3 A method of making a fire-fighting foam, comprising foaming a foam concentrate composition with an aqueous liquid to form the fire-fighting foam, wherein the foam concentrate composition comprises: (a) trimethyl glycine in an amount that is effective to depress the freezing point of said foam concentrate composition below 0° C.; (b) at least one surfactant selected from the group consisting of anionic, zwitterionic and nonionic surfactants; and (c) a foam stabilizing agent; wherein the fire-fighting foam includes 0.25 wt %-3.6 wt % of the trimethyl glycine. ### Claim 4 (depends on 3) The method according to claim 3, wherein said aqueous liquid is brackish water or seawater. ### Claim 5 (depends on 1) A method of extinguishing a fire comprising spraying a foam according to claim 1 on the fire at a rate effective to extinguish said fire. ### Claim 6 (depends on 1) The fire-fighting foam according to claim 1, further comprising a first additional anionic, zwitterionic or nonionic surfactant. ### Claim 7 (depends on 6) The fire-fighting foam according to claim 6, further comprising a second additional anionic, zwitterionic or nonionic surfactant. ### Claim 8 (depends on 6) The fire-fighting foam according to claim 6, wherein said at least one surfactant and said first additional surfactant are of different charge types. ### Claim 9 (depends on 7) The fire-fighting foam according to claim 7, wherein said at least one surfactant and said first and second additional surfactants are of different charge types. ### Claim 10 (depends on 1) The fire-fighting foam according to claim 1, further comprising a high molecular weight water-soluble polymer that precipitates on contact with a water-miscible fuel. ### Claim 11 (depends on 1) The fire-fighting foam according to claim 1, further comprising a corrosion inhibitor. ### Claim 12 (depends on 1) The fire-fighting foam according to claim 1, wherein said foam stabilizing agent is a polymeric foam stabilizer. ### Claim 13 (depends on 1) The fire-fighting foam according to claim 1, further comprising a biocide. ### Claim 14 (depends on 1) The fire-fighting foam according to claim 1, wherein at least one surfactant is a non-fluorinated surfactant. ### Claim 15 (depends on 1) The fire-fighting foam according to claim 1, wherein all surfactants are non-fluorinated surfactants. ### Claim 16 (depends on 1) The fire-fighting foam according to claim 1, further comprising a zwitterionic or anionic perfluoroalkyl surfactant. ### Claim 17 (depends on 1) The fire-fighting foam according to claim 1, wherein the foam is free of ethylene glycol and propylene glycol. ### Claim 18 (depends on 1) The fire-fighting foam according to claim 1, further comprising at least one high molecular weight water-soluble polymer. ### Claim 19 (depends on 18) The fire-fighting foam according to claim 18, wherein the polymer is a polysaccharide gum present in an amount up to 5 wt %. ### Claim 20 (depends on 18) The fire-fighting foam according to claim 18, wherein the polymer is an acrylic polymer present in an amount up to 5 wt %. ### Claim 21 (depends on 1) The fire-fighting foam according to claim 1, wherein the foam further comprises glycerine. ### Claim 22 (depends on 1) The fire-fighting foam according to claim 1, wherein the foam stabilizing agent is fluorine free. ### Claim 23 (depends on 1) The fire-fighting foam of claim 1, wherein the at least one surfactant comprises anionic surfactant, zwitterionic surfactant, and nonionic surfactant. ### Claim 24 (depends on 1) The fire-fighting foam of claim 1 wherein the at least one surfactant comprises: an anionic surfactant comprising C8-C16 alkyl sulfate and/or C8-C16 alkyl sulfonate; a zwitterionic surfactant comprising C6-C14 alkyl betaine and/or C6-C14 alkyl sulfobetaine; and a nonionic surfactant comprising an alkyl polyglycoside. ### Claim 25 (depends on 1) The fire-fighting foam of claim 1, wherein the fire-fighting foam further comprises ethylene glycol and/or propylene glycol. ### Claim 26 A fire-fighting foam comprising: (a) 0.25 wt %-3.6 wt % trimethyl glycine; (b) anionic surfactant; (c) zwitterionic surfactant; (d) nonionic surfactant; (e) polymeric foam stabilizing agent; and (f) an aqueous liquid. ### Claim 27 (depends on 26) The fire-fighting foam of claim 26, wherein an anionic surfactant comprises C8-C16 alkyl sulfate and/or C8-C16 alkyl sulfonate, the zwitterionic surfactant comprises C6-C14 alkyl betaine and/or C6-C14 alkyl sulfobetaine, and the nonionic surfactant comprises an alkyl polyglycoside. ### Claim 28 A method of making a fire-fighting foam, comprising foaming a foam concentrate composition with an aqueous liquid to form the fire-fighting foam, wherein the foam concentrate composition comprises: (a) trimethyl glycine in an amount that is effective to depress the freezing point of said foam concentrate composition below 0° C.; (b) 0.1 to 10 wt % anionic surfactant; (c) 0.1 to 10 wt % zwitterionic surfactant; (d) 0.3 to 15 wt % nonionic surfactant; and (e) 0.5-50 wt % foam stabilizing agent; wherein the fire-fighting foam includes 0.25 wt %-3.6 wt % of the trimethyl glycine. ### Claim 29 (depends on 28) The method of claim 28, wherein the foam concentrate composition comprises 5 to 60 wt % of the trimethyl glycine.