Method of making adhesive-repellent coatings based on polysiloxane compositions, and their application in the coating of paper.

摘要

In the production of non-adherent coated paper substrate by applying to the substrate a solvent-containing mixture comprising (A) 100 parts by weight of an alpha , omega -dihydroxypolydimethylsiloxane having a viscosity between 105 and 5. 107 cP at 20 DEG C., (B) about 1 to 20 parts by weight of a polyorganosiloxane which is terminally blocked with trimethylsiloxy groups, contains Si-bonded hydrogen and has about 10 to 40 CH3Si(H)O units, and (C) about 1 to 20 parts by weight of a heavy metal carboxylate or dialkyl-tin carboxylate, and then heating the substrate to harden the coating, the improvement which comprises including in the mixture applied to the substrate (D) about 0.5 to 10 parts by weight of disilamorpholinesiloxane which is obtained by reacting a chloromethylpolymethylsiloxane of the formula ClCH2(CH3)SiO[Si(CH3)CH2ClO]nSi(CH3)2CH2Cl in which n denotes a value between 2 and 200, with at most an equivalent amount of a primary C4-18 alkyl or alkenyl or cycloalkylamine, e.g. butylamine, hexylamine, cyclohexylamine, 2-ethylhexylamine and allylamine. The coating hardens in a very short time in a drying oven but at normal temperatures the mass has a relatively long pot life.