Method of manufacturing gypsum board with improved fire resistance

Patent metadata

Field	Value
Publication number	US-12031328-B2
Application number	US-202217750548-A
Country	US
Kind code	B2
Filing date	May 23, 2022
Priority date	Jan 23, 2017
Publication date	Jul 9, 2024
Grant date	Jul 9, 2024

Abstract

The present disclosure is directed to a method of manufacturing gypsum board as well as the resulting gypsum board. The method comprises providing a gypsum slurry with a shrinkage-reducing additive comprising a metal salt of an acid, a silica, or a mixture thereof. As a result, the gypsum board includes gypsum and a shrinkage-reducing additive comprising a metal salt of an acid, a silica, or a mixture thereof. The gypsum board exhibits an area shrinkage of less than 10%.

First claim

The invention claimed is:

1. A method for manufacturing a gypsum board, the method comprising:
providing a gypsum slurry comprising stucco and a shrinkage-reducing additive comprising a silica comprising colloidal silica, precipitated silica, or a mixutre thereof onto a bottom facing material, wherein the shrinkage-reducing additive is present in an amount of 0.05 wt. % or more to 2 wt. % or less based on the weight of the stucco, and
providing a top facing material on the gypsum slurry,
wherein the gypsum board exhibits an area shrinkage of 10% or less, and
wherein the gypsum board exhibits a nail pull strength of 70 lb f or more.

2. The method according to claim 1 , wherein the silica comprises colloidal silica.

3. The method according to claim 1 , wherein the silica comprises precipitated silica.

4. The method according to claim 1 , wherein the shrinkage-reducing additive has a particle size of 5 nanometers or more to 100 micrometers or less.

5. The method according to claim 1 , wherein the gypsum board exhibits an area shrinkage of 8% or less.

6. The method according to claim 1 , wherein the shrinkage-reducing additive is present in an amount of 0.05 wt. % or more to 1 wt. % or less.

7. The method according to claim 1 , wherein the shrinkage-reducing additive has an average particle size of 5 nanometers or more to 100 nanometers or less.

8. A gypsum board comprising:
gypsum and a shrinkage-reducing additive comprising a silica wherein the shrinkage-reducing additive is present in an amount of 0.05 wt. % or more to 2 wt. % or less based on the weight of the gypsum, wherein the silica is from colloidal silica, precipitated silica, or a mixutre thereof,
wherein the gypsum board exhibits an area shrinkage of 10% or less, and
wherein the gypsum board exhibits a nail pull strength of 70 lb f or more.

9. The gypsum board according to claim 8 , wherein the silica comprises colloidal silica.

10. The gypsum board according to claim 8 , wherein the silica comprises precipitated silica.

11. The gypsum board according to claim 8 , wherein the shrinkage-reducing additive has a particle size of 5 nanometers or more to 100 micrometers or less.

12. The gypsum board according to claim 8 , wherein the gypsum board exhibits an area shrinkage of 8% or less.

13. The gypsum board according to claim 8 , wherein shrinkage-reducing additive is present in an amount of 0.05 wt. % or more to 1 wt. % or less.

14. The gypsum board according to claim 8 , wherein the shrinkage-reducing additive has an average particle size of 5 nanometers or more to 100 nanometers or less.

Assignees

• Gold Bond Building Products Llc

Inventors

• Stav Eli
• Ling Jie
• Busche Brad
• Bailey Joseph J
• Iyer R G
• Evans Veda

Classifications

• C04B22/10

  containing carbon in the anion, e.g. carbonates · CPC title

• C04B2111/28

  Fire resistance, i.e. materials resistant to accidental fires or high temperatures · CPC title

• C04B22/149

  Iron-sulfates · CPC title

• C04B22/12

  containing halogen in the anion · CPC title

• C04B22/16

  containing phosphorus in the anion, e.g. phosphates · CPC title