Carboxymethylcellulose as protective colloid

摘要

If carboxymethylcellulose is used as a protective colloid, dispersions can be obtained which result in adequate cement stability when used as binders in roof stone colors. A dispersion is used containing 0.1-3, preferably 0.1-1.5 wt.%, (relative to the total monomer content) of carboxymethylcellulose (CMC), obtained by emulsion polymerization of a monomer composition consisting of wt.%): (a) (meth)acrylic acid ester (85-99.8) with 1-12C alkanols, and/or vinylaromatic monomers; (b) copolymerisable carboxylic acids and/or their amides (0.2-5); and (c) other monomers. The dispersion is polymerized as an aqueous emulsion in order to prepare roof stone colors. Independent claims are included for: (1) a roof stone color containing a dispersion including CMC as protective colloid and prepared by emulsion polymerization as under (a)-(c) above; and (2) a roof stone coated with the roof stone color.