Prodn. of aq. dispersions for electro-dip coating baths - by mixing dispersion of, pref., amino-epoxy resin and blocked isocyanate with separate dispersion of copolymer tert. amino gp.

摘要

Prodn. of aq. dispersions (I) contg. (A) 10-94 wt.% polymerisation, poly-condensn. or polyaddn. prod. which can be dispersed in water by protonation with acids, (B) 1-40 wt.% tert. amino gp.-contg. copolymer other than (A), with mol.wt. 2000-100,000 and Tg below +30 deg.C, which is based on mono-unsatd. monomers and is also dispersible in water as above, and (C) 5-50 wt.% crosslinker, involves mixing an aq. dispersion contg. (A) and (C) with a separately prepd. aq. dispersion of (B). (A) is an amino-epoxy resin, (C) is a blocked di- or poly-isocyanate, and (B) is dispersed in the presence of a dialkyl-tin cpd. (II). USE/ADVANTAGE - (I) are useful as components of electro-dipcoating baths; baths contg. (I) give coatings with good anticorrosion properties combined with good mechanical properties, esp. elasticitid