Use, as antiadhesives agent and/or water repellents, of grafted functionalized polyorganosiloxanes

A method for the preparation of a printable, writable and markable coating composition, in the form of an aqueous dispersion, comprising the steps of:

• (a) making an aqueous emulsion comprising, as antiadhesive agents and/or water repellents, grafted functionalized polyorganosiloxanes comprising grafted copolymer moieties, derived from at least one ethylenically unsaturated monomer which is optionally polymerized via a radical route and which is selected from the group consisting of:
• (i) monoethylenically unsaturated esters of a saturated carboxylic acid;
• (ii) saturated esters or monoethylenically unsaturated carboxamides;
• (iii) monoethylenically unsaturated nitrites;
• (iv) monoethylenically unsaturated carboxylic acids;
• (v) hydroxyalkyl or aminoalkyl esters of monoethylenically unsaturated carboxylic acids;
• (vi) vinylaromatic monomers;
• and
• (vii) dicyclopentadienyl acrylate or methacrylate;
• and from a linear functionalized polyorganosiloxane (I) of the following formula (I):
• ##STR3## wherein:
• R are the same or different and represent a linear or branched C.sub.1 -C.sub.18 alkyl group, a linear or branched C.sub.2 -C.sub.20 alkenyl group, or a C.sub.6 -C.sub.12 aryl or aralkyl group, and is optionally substituted with halogen atoms;
• X are the same or different and represent a reactive function linked to a silicon atom by an Si--C or Si--O--C bond and is an epoxy functional hydrocarbon group containing from 2 to 20 carbon atoms;
• Y are the same or different and represent an ethylenically unsaturated hydrocarbon residue which optionally contains one or more hetero elements O or N, the residue being linked to a silicon atom of the moiety of formula (I) by an Si--C bond and being capable of reacting via a radical route with at least one ethylenically unsaturated monomer;
• Z.sub.1, Z.sub.2 and Z.sub.3 represent numbers of moieties;
• the number of moieties Z.sub.2 and Z.sub.3 of formula (I) being such that the polyorganosiloxanes contain:
• from 1 to 100 milliequivalents of functions X per 100 grams of polyorganosiloxane of formula (I);
• and
• from 10 to 500 milliequivalents of residues Y per 100 grams of polyorganosiloxane of formula (I).