Patent ID: 8329308

Claim:
A method of preparing a cementitious article comprising: (a) preparing a cementitious slurry, wherein the cementitious slurry comprises: (i) cementitious material present in an amount of at least about 50% by weight of the cementitious slurry; (ii) polyvinyl acetate or polyvinyl alcohol polymer or copolymer present in an amount of from about 0.1% to about 2% by weight of the cementitious slurry; (iii) boric acid present in an amount of from about 0.1% to about 1% by weight of the cementitious slurry; and (iv) monobasic phosphate present in an amount of from about 0.1% to about 1% by weight of the cementitious slurry; (b) depositing the cementitious slurry onto an advancing sheet of facer material; and (c) allowing the slurry to set.