To rapidly capture electric charges, to keep them constant and to obtain high heat stability by using a specified metallic carboxylate and a specified metallic sulfonate as electric charge improvers in a powdery coating material and in an electret material.
A metallic carboxylate and a metallic sulfonate are used as electric charge improvers in a powdery coating material and in an electret material and are used in an electrostatic separation method. Each of the compds. is prepd. by reaction with (a) an acid of formula I, II, III or the like, (b) a heteroarom. mono- or dicarboxylic acid, (c) poly(styrenesulfonic acid), poly(acrylic acid), poly(methacrylic acid) or the like or (d) a carboxyl- and/or sulfo- contg. polyester. The cation of the metal is di- or trivalent. In the formulae I-III, R1 is 1-18C straight chain or branched chain alkyl and R2-R6 are each H, 1-8 alkyl or the like.
BAUR RUEDIGER DR
MACHOLDT HANS-TOBIAS DR
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