US 12,090,744 B2
Composite gypsum board and methods related thereto
Alfred C. Li, Naperville, IL (US); Weixin D. Song, Vernon Hills, IL (US); Yijun Sang, Oak Park, IL (US); Gregg G. Diefenbacher, Mars, PA (US); Annamaria Vilinska, Chicago, IL (US); Brian J. Christ, Burlington, IA (US); Fredrick T. Jones, Grayslake, IL (US); and Bradley W. Todd, Hainesville, IL (US)
Assigned to UNITED STATES GYPSUM COMPANY, Chicago, IL (US)
Filed by United States Gypsum Company, Chicago, IL (US)
Filed on Jun. 17, 2016, as Appl. No. 15/186,257.
Claims priority of provisional application 62/184,060, filed on Jun. 24, 2015.
Claims priority of provisional application 62/290,361, filed on Feb. 2, 2016.
Prior Publication US 2016/0376191 A1, Dec. 29, 2016
This patent is subject to a terminal disclaimer.
Int. Cl. B32B 7/02 (2019.01); B32B 13/02 (2006.01); B32B 13/04 (2006.01); B32B 13/08 (2006.01); B32B 13/14 (2006.01); B32B 37/14 (2006.01); C04B 11/00 (2006.01); C04B 22/16 (2006.01); C04B 24/38 (2006.01); C04B 28/14 (2006.01); E04C 2/04 (2006.01); B32B 37/15 (2006.01); C04B 111/00 (2006.01); C04B 111/30 (2006.01)
CPC B32B 7/02 (2013.01) [B32B 13/02 (2013.01); B32B 13/04 (2013.01); B32B 13/08 (2013.01); B32B 13/14 (2013.01); B32B 37/144 (2013.01); C04B 11/00 (2013.01); C04B 11/002 (2013.01); C04B 22/16 (2013.01); C04B 24/383 (2013.01); C04B 28/14 (2013.01); E04C 2/043 (2013.01); B32B 37/15 (2013.01); B32B 2250/04 (2013.01); B32B 2250/40 (2013.01); B32B 2260/028 (2013.01); B32B 2260/046 (2013.01); B32B 2262/101 (2013.01); B32B 2264/02 (2013.01); B32B 2264/0228 (2013.01); B32B 2264/06 (2013.01); B32B 2264/062 (2013.01); B32B 2307/50 (2013.01); B32B 2307/51 (2013.01); B32B 2307/536 (2013.01); B32B 2307/54 (2013.01); B32B 2307/718 (2013.01); B32B 2307/72 (2013.01); B32B 2419/00 (2013.01); B32B 2419/04 (2013.01); B32B 2419/06 (2013.01); B32B 2607/00 (2013.01); C04B 2111/00413 (2013.01); C04B 2111/0062 (2013.01); C04B 2111/30 (2013.01); C04B 2201/20 (2013.01)] 24 Claims
OG exemplary drawing
 
1. A composite gypsum board comprising:
(a) a board core comprising set gypsum formed from at least water and stucco, the core defining a first core face; and
(b) a concentrated layer formed from at least water, stucco, and uncooked, non-migratory, strength-enhancing starch as an enhancing additive, the concentrated layer disposed in bonding relation to the first core face;
(i) the concentrated layer having a concentration of the enhancing additive that is greater than zero and is at least 2.5 times a concentration of an enhancing additive, if any, in the board core,
(ii) the concentrated layer having a dry thickness between about 0.05 and about 0.23 cm, and the board core having a dry thickness greater than the thickness of the concentrated layer,
(iii) the concentrated layer having an average core hardness that is at least 1.5 times greater than an average core hardness of the board core,
(iv) the composite gypsum board having a nail pull resistance according to ASTM C473-10, Method B, of at least 72 lbs. of force,
(v) the board core forms at least 80% of the bulk volume of the board, and
(vi) the composite gypsum board has a dry density of about 33 pcf (about 530 kg/m3) or less, wherein the ratio of a nail pull resistance to the dry density of the composite gypsum board is at least 2.18:1.