IP Library Granted Patent US 11,819,722
Granted Patent B1
US 11,819,722 · App. 18/060,943 · Granted Nov 21, 2023

Long-term fire retardant with corrosion inhibitors and methods for making and using same

Inventors: Dennis Hulbert (Corvallis, MT); Robert J. Burnham (Stevensville, MT); Michael S. Schnarr (Roseville, CA); Gerald Geissler (Kailua-Kona, HI); David W. Wilkening (Ronan, MT); Joseph McLellan (Rocklin, CA)
Assignee: FRS Group, LLC
A62D1/0028A62C3/0228A62D1/0042
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Quick Facts
Patent No.
US 11,819,722
App. No.
18/060,943
Granted
Nov 21, 2023
Kind
B1
Abstract

A forest fire retardant composition contains water and a retardant compound that includes a halide salt, a non-halide salt, a metal oxide, a metal hydroxide, or combinations thereof. The halide salt may be magnesium chloride, calcium chloride, or both. The magnesium chloride hydrate has a formula MgCl 2 (H 2 O) x , wherein x is at least one of x=1, 2, 4, 6, 8, or 12. The calcium chloride hydrate has a formula CaCl 2 (H 2 O) x , wherein x is at least one of 1, 2, 4, or 6. The composition may be in the form of 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 (39)

1. A forest fire retardant liquid concentrate, comprising:

a magnesium chloride salt solution comprising magnesium chloride dissolved in water, the magnesium chloride being present in the magnesium chloride salt solution in an amount having a weight percent of about 15% to about 45% relative to the total weight of the magnesium chloride salt solution, and the magnesium chloride salt solution being present in the liquid concentrate in an amount having a weight percent of about 85% to about 99% relative to the total weight of the liquid concentrate;

a corrosion inhibitor for at least one of iron, brass, or aluminum, present in the liquid concentrate in an amount having a weight percent of about 0.25% to about 5.0% relative to the weight of the magnesium chloride in the liquid concentrate; and

a thickening agent, present in the liquid concentrate in an amount having a weight percent of about 0.75% to about 5.0% relative to the weight of the magnesium chloride in the liquid concentrate.

2. The liquid concentrate of claim 1 , wherein the magnesium chloride is present in the magnesium chloride salt solution in a weight percent of about 25% to about 35% relative to the total weight of the magnesium chloride salt solution.

3. The liquid concentrate of claim 1 , wherein the corrosion inhibitor comprises an organic amine.

4. The liquid concentrate of claim 3 , wherein the organic amine comprises triethanolamine.

5. The liquid concentrate of claim 1 , wherein the thickening agent comprises a polysaccharide gum.

6. The liquid concentrate of claim 5 , wherein the polysaccharide gum comprises xanthan gum.

7. The liquid concentrate of claim 1 , further comprising a colorant present in the liquid concentrate in an amount having a weight percent of about 0.25% to about 6.0% relative to the weight of the magnesium chloride in the liquid concentrate.

8. The liquid concentrate of claim 7 , wherein the colorant comprises a fluorescent pigment.

9. The liquid concentrate of claim 1 , further comprising a surfactant present in the liquid concentrate in an amount having a weight percent of about 0.01% to about 1.25% relative to the weight of the magnesium chloride in the liquid concentrate.

10. A kit comprising:

a sealed container which contains the liquid concentrate of claim 1 substantially in the absence of external moisture; and

instructions for using the liquid concentrate to make a final diluted product useful to suppress, retard, or contain forest fires.

11. The kit of claim 10 , wherein the magnesium chloride is present in the final diluted product in an amount having a weight percent of about 7% to about 30% relative to the total weight of the final diluted product.

12. The kit of claim 10 , further comprising:

a tank for diluting the liquid concentrate to make the final diluted product; and

a wand or a hose for applying the final diluted product.

13. A forest fire retardant liquid concentrate, comprising:

a liquid salt solution comprising magnesium chloride dissolved in water;

an organic amine present in the liquid concentrate in a weight percent of about 1.0% to about 3.5% relative to the weight of the magnesium chloride in the liquid concentrate; and

a surfactant present in the liquid concentrate in an amount having a weight percent of about 0.01% to about 1.25% relative to the weight of the magnesium chloride in the liquid concentrate.

14. The liquid concentrate of claim 13 , wherein the liquid salt solution is present in the liquid concentrate in an amount having a weight percent of about 85% to about 99% relative to the total weight of the liquid concentrate.

15. The liquid concentrate of claim 13 , wherein the magnesium chloride is present in the liquid concentrate in an amount having a weight percent of about 20% to 45% relative to the total weight of the liquid concentrate.

16. The liquid concentrate of claim 13 , wherein the magnesium chloride is present in the liquid concentrate in an amount having a weight percent of about 25% to about 35% relative to the total weight of the liquid concentrate.

17. The liquid concentrate of claim 13 , wherein the organic amine comprises triethanolamine.

18. The liquid concentrate of claim 13 , further comprising a thickening agent present in the liquid concentrate in an amount having a weight percent of about 0.75% to about 5.0% relative to the weight of the magnesium chloride in the liquid concentrate.

19. The liquid concentrate of claim 18 , wherein the thickening agent comprises a polysaccharide gum.

20. The liquid concentrate of claim 19 , wherein the polysaccharide gum comprises xanthan gum.

21. The liquid concentrate of claim 13 , further comprising a colorant present in the liquid concentrate in an amount having a weight percent of about 0.25% to about 6.0% relative to the weight of the magnesium chloride in the liquid concentrate.

22. The liquid concentrate of claim 21 , wherein the colorant comprises a fluorescent pigment.

23. A kit comprising:

a sealed container which contains the liquid concentrate of claim 13 substantially in the absence of external moisture; and

instructions for using the liquid concentrate to make a final diluted product useful to suppress, retard, or contain forest fires.

24. The kit of claim 23 , wherein the magnesium salt is present in the final diluted product in an amount having a weight percent of about 7% to about 30% relative to the total weight of the final diluted product.

25. The kit of claim 23 , further comprising:

a tank for diluting the liquid concentrate to make the final diluted product; and

a wand or a hose for applying the final diluted product.

Assignments (8)
NOTES PATENT SECURITY AGREEMENT Recorded Jan 2, 2026
From: PERIMETER SOLUTIONS LP
To: U.S. BANK TRUST COMPANY, NATIONAL ASSOCIATION, AS NOTES COLLATERAL AGENT
Reel/Frame 074174/0258 →
SECURITY INTEREST Recorded Jan 2, 2026
From: PERIMETER SOLUTIONS LP
To: U.S. BANK TRUST COMPANY, NATIONAL ASSOCIATION, AS NOTES COLLATERAL AGENT
Reel/Frame 073353/0552 →
PATENT SECURITY AGREEMENT Recorded Dec 19, 2025
From: PERIMETER SOLUTIONS LP
To: MORGAN STANLEY SENIOR FUNDING, INC., AS ADMINISTRATIVE AGENT
Reel/Frame 074007/0465 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 2, 2025
From: FORTRESS NORTH AMERICA, LLC; FRS GROUP LLC; COMPASS MINERALS AMERICA INC.
To: PERIMETER SOLUTIONS, LP
Reel/Frame 072791/0298 →
RELEASE OF SECURITY INTEREST Recorded Jun 2, 2025
From: JPMORGAN CHASE BANK, N.A. AS COLLATERAL AGENT
To: FRS GROUP LLC
Reel/Frame 071285/0944 →
SECURITY INTEREST Recorded Jun 6, 2023
From: FRS GROUP LLC
To: JPMORGAN CHASE BANK, N.A., AS COLLATERAL AGENT
Reel/Frame 063868/0441 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Dec 13, 2022
From: HULBERT, DENNIS; BURNHAM, ROBERT J.; SCHNARR, MICHAEL S.; MCLELLAN, JOSEPH; GEISSLER, GERALD
To: FRS GROUP, LLC
Reel/Frame 062067/0100 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Dec 13, 2022
From: WILKENING, DAVID W.
To: FRS GROUP, LLC
Reel/Frame 062067/0179 →
Cited By (3)
US 12,214,236 US 12,214,237 US 12,629,555