US 12,031,328 B2
Method of manufacturing gypsum board with improved fire resistance
Eli Stav, Chrlotte, NC (US); Jie Ling, Irmo, SC (US); Brad Busche, Shelby, NC (US); Joseph J. Bailey, Charlotte, NC (US); R. G. Iyer, Fort Mill, SC (US); and Veda Evans, Charlotte, NC (US)
Assigned to Gold Bond Building Products, LLC, Charlotte, NC (US)
Filed by Gold Bond Building Products, LLC, Charlotte, NC (US)
Filed on May 23, 2022, as Appl. No. 17/750,548.
Application 17/750,548 is a continuation of application No. 15/877,993, filed on Jan. 23, 2018, granted, now 11,339,572.
Claims priority of provisional application 62/449,484, filed on Jan. 23, 2017.
Prior Publication US 2022/0282484 A1, Sep. 8, 2022
Int. Cl. E04C 2/04 (2006.01); C04B 14/06 (2006.01); C04B 22/10 (2006.01); C04B 22/12 (2006.01); C04B 22/14 (2006.01); C04B 22/16 (2006.01); C04B 28/16 (2006.01); C04B 111/00 (2006.01); C04B 111/28 (2006.01)
CPC E04C 2/043 (2013.01) [C04B 14/062 (2013.01); C04B 14/066 (2013.01); C04B 22/10 (2013.01); C04B 22/12 (2013.01); C04B 22/124 (2013.01); C04B 22/142 (2013.01); C04B 22/149 (2013.01); C04B 22/16 (2013.01); C04B 28/165 (2013.01); C04B 2111/0062 (2013.01); C04B 2111/28 (2013.01)] 14 Claims
OG exemplary drawing
 
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 lbf or more.
 
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 lbf or more.