Aq. dispersion for prodn. of matt coatings by electrodeposition - contains fluorine-contg. poly:carboxylic acid resin and epoxy-silane cpd.

摘要

Opacifiable aq. fluorine-based dispersion (I) contians, as resin component, a fluorine-based polycarboxylic acid resin (II) with an epoxysilane cpd. (III). (I) is produced by dissolved dissolving or dispersing (II) and an alicyclic epoxysilane cpd. (III) in an organic solvent, and heating the soln. obtd. until the acid no. of (II) is reduced by 1 or more, then adding a neutralising agent and dispersing in water. (II) has Mn 2000-100,000 and acid no. 20-200, and is pref. made by reaction of the anhydride of a dibasic acid with a fluorine-based OH gp.-contg. polymer obtd. by copolymerisation of a hydroxyvinyl ether and/or hydroxyallyl ether with a fluoro-olefin; (III) contains an epoxy gp. and at least one alkoxysilane gp.; amt. of (III) is 0.1-20 pts. wt./100 pts. wt. solid content of (II); (III) has an alicyclic/aliphatic epoxy gp. and at wt./100 pts. wt. solid content of (II); (III) has an alicyclic/ aliphatic epoxy gp. and at least one alkoxysilane gp.; (II) is dissolved or dispersed as above, then (III) is added before or after neutralisation and the mixt. is dispersed in water after neutralisation if (III) is added before neutralisation. USE/ADVANTAGE - (I) is useful in compsns. for anionic electrodeposition. A matt coating compsn. contg. (I) is claimed, for use in this application. The invention enables the prodn. of a stable F-based coating compsn. for prodn. of a matt surface by anionic electrodeposition.