Granted Patent B2

US 9,889,579 · App. 14/476,078 · Granted Feb 13, 2018

Abstract

Claims (53)

1. A foamed gypsum slurry composition, comprising:

stucco;

gauging water;

a foam comprising foaming water, a foaming agent and air;

a first coalescing agent having a first cloud point temperature; and

a second coalescing agent having a second cloud point temperature that is different from the first cloud point temperature;

wherein the foamed gypsum slurry composition has a mix temperature, and the first and second coalescing agents have a blended cloud point temperature that is lower than the mix temperature.

2. The foamed gypsum slurry composition of claim 1 , wherein the blended cloud point temperature is lower than the mix temperature by about 5° F. to about 30° F.

3. The foamed gypsum slurry composition of claim 1 , wherein the blended cloud point temperature is lower than the mix temperature by about 5° F. to about 10° F.

4. The foamed gypsum slurry of claim 1 , wherein the first coalescing agent has a cloud point temperature of about 68° F., and the second coalescing agent has a cloud point temperature of about 110° F.

5. The foamed gypsum slurry of claim 1 , wherein the first or second coalescing agent is a polyether block copolymer surfactant.

6. The foamed gypsum slurry of claim 5 , wherein the polyether block copolymer surfactant is an ethylene oxide-propylene oxide block copolymer and/or reverse block copolymer.

7. The foamed gypsum slurry of claim 1 , wherein the first or second coalescing agent is an alkoxylated alcohol surfactant.

8. The foamed gypsum slurry of claim 7 , wherein the alkoxylated alcohol surfactant is a fatty alcohol alkoxylate.

9. The foamed gypsum slurry of claim 1 , wherein the first and/or second coalescing agent has a delayed coalescing activity.

10. A method for making a foamed gypsum slurry composition, comprising the steps of:

providing a gypsum slurry comprising stucco and gauging water;

generating a foam comprising foam water, a foaming agent and air;

introducing the foam to the gypsum slurry to form a foamed gypsum slurry having a mix temperature;

adding a first coalescing agent to the foamed gypsum slurry, the first coalescing agent having a first cloud point temperature; and

adding a second coalescing agent to the foamed gypsum slurry, the second coalescing agent having a second cloud point temperature that is different from the first cloud point temperature;

wherein the first and second coalescing agents have a blended cloud point temperature that is lower than the mix temperature.

11. The method of claim 10 , wherein the first and second coalescing agents have a blended cloud point temperature that is lower than the mix temperature by about 5° F. to about 30° F.

12. The method of claim 10 , wherein the first and second coalescing agents have a blended cloud point temperature that is lower than the mix temperature by about 5° F. to about 10° F.

13. The method of claim 10 , further comprising the steps of:

determining the mix temperature of the foamed gypsum slurry; and

adjusting the ratio of the first and second coalescing agents to provide a blended cloud point temperature that is lower that the mix temperature.

14. The method of claim 13 , wherein the first and second coalescing agents have a blended cloud point temperature that is lower than the mix temperature by about 5° F. to about 30° F.

15. The method of claim 13 , wherein the first and second coalescing agents have a blended cloud point temperature that is lower than the mix temperature by about 5° F. to about 10° F.

16. The method of claim 10 , wherein the first coalescing agent has a cloud point temperature of about 68° F., and the second coalescing agent has a cloud point temperature of about 110° F.

17. The method of claim 10 , wherein the first and second coalescing agents are added to the foamed gypsum slurry by mixing with a component of the composition selected from the group consisting of: the gypsum slurry, the gauging water, the foam water, the foaming agent, the foam, and combinations thereof.

18. The method of claim 17 , wherein the first and second coalescing agents are added separately to the foamed gypsum slurry by mixing with different components of the composition.

19. The method of claim 10 , further comprising the steps of:

transferring the gypsum slurry from a mixer to a canister and to a boot; and

introducing the foam to the gypsum slurry in the mixer or the canister; and

wherein the first and second coalescing agents are added to the foamed gypsum slurry at a location selected from the group consisting of: the mixer, the canister, the boot, and combinations thereof.

20. The method of claim 19 , wherein the first and second coalescing agents are added separately to the foamed gypsum slurry at different locations.

21. The method of claim 10 , wherein the first or second coalescing agent is a polyether block copolymer surfactant.

22. The method of claim 21 , wherein the polyether block copolymer surfactant is an ethylene oxide-propylene oxide block copolymer and/or reverse block copolymer.

23. The method of claim 10 , wherein the first or second coalescing agent is an alkoxylated alcohol surfactant.

24. The method of claim 23 , wherein the alkoxylated alcohol surfactant is a fatty alcohol alkoxylate.

25. A method for making a gypsum board, comprising the steps of:

providing a gypsum slurry comprising stucco and water;

generating a foam comprising water, a foaming agent and air;

introducing the foam to the gypsum slurry to form a foamed gypsum slurry having a mix temperature;

determining the mix temperature of the foamed gypsum slurry;

adding a first coalescing agent to the foamed gypsum slurry, the first coalescing agent having a first cloud point temperature;

adding a second coalescing agent to the foamed gypsum slurry, the second coalescing agent having a second cloud point temperature that is different from the first cloud point temperature, wherein the first and second coalescing agents are added in a ratio that provides a blended cloud point temperature that is lower that the mix temperature by about 5° F., to about 30° F.;

applying the foamed gypsum slurry to a first facing material;

applying a second facing material atop the foamed gypsum slurry to sandwich the foamed gypsum slurry between the first and second facing materials;

forming the foamed gypsum slurry to a desired thickness; and

drying the foamed gypsum slurry to form a board.

26. The method of claim 25 , wherein the first and second coalescing agents are added in a ratio that provides a blended cloud point temperature that is lower that the mix temperature by about 5° F. to about 10° F.

Assignments (9)