COLORANT COMPOSITION CONTAINING TITANIUM OXIDE TREATED WITH METHYLHYDROGENPOLYSILOXANE

摘要

PURPOSE: To obtain a colorant composition containing titanium oxide treated with methylhydrogenpolysiloxane, being effective to make a polyolefin resin proof against yellowing otherwise occurring as a result of the deterioration of titanium oxide and a phenolic antioxidant by mixing the resin with a colorant component being titanium oxide surface-coated with methylhydrogenpolysiloxane. CONSTITUTION: A polyolefin resin is colored by mixing it with titanium oxide particles surface-coated with methylhydrogenpolysiloxane. The titanium oxide used should be rutile titanium oxide having a particle diameter distribution of 0.05-0.45μm and a mean particle diameter of 0.20-0.30μm. The methylhydrogenpolysiloxane used is desirably one having a siloxane chain length of 12 or below and is used in an amount of desirably 0.1-3 pts.wt. per pt.wt. titanium oxide. The coating is carried out by adding the methylhydrogenpolysiloxane to the titanium oxide during its grinding by means of e.g. a micronizer. The amount of the colorant added is such that 0.01-400 pts.wt. titanium oxide is added to 100 pts.wt. polyolefin resin.