Patent ID: 8741056

Claim:
A gypsum composition with an O/W wax dispersion added, the O/W wax dispersion comprising: at least 30% by wt. water, at least 20% by wt. wax phase as the disperse phase, wherein the wax phase has a saponification number greater than 0.2 mgKOH/g, at least 0.1% by wt. of an emulsifier or thickening agent as dispersing adjuvant, and at least one of polyvinyl alcohols and partially hydrolysed polyvinyl alcohols, wherein the wax phase comprises the following, based on the wax phase: 50 to 98% by wt. aliphatic hydrocarbons (HC) or mixtures thereof, each with a solidification point above 50° C. and below 95° C., 2 to below 50% by wt. from polar, long-chain compounds with at least 18 carbon atoms, containing one or more groups selected from a carboxyl group, a partially derivatized carboxyl group, an ether group, and at least one hydroxyl group (—OH), per molecule, but no more than three of the aforementioned groups in one molecule together, and carnauba wax forming part of the 2 to below 50% by wt. of the polar, long chain compounds; wherein the gypsum composition comprises greater than 50% by wt. of calcium sulphate dehydrate and 0.1 to 5% by wt. of the wax phase of the O/W wax dispersion.