Coloured aggregate (e.g. sand) prodn. - using dye or pigment and binder esp. bisphenol A epoxy resin

摘要

Process for preparing coloured solid aggregates (e.g. coloured sand) comprises (a) mixing the aggregate at 30-100 degrees C, (b) adding to the stirred mixt., 0.1-7 wt.% (based on aggregate) of a coating binder, (c) adding 0.1-1 wt. % (based on aggregate) of a pigment or dye in the form of a powder, paste or liquid, (d) heating at 30-130 degrees C and (e) homogenising by mixing for 1-15 mins. binder is pref. a bisphenol A-epichlorohydrin epoxy resin opt. contg. a polyglycol.