摘要 |
A process for the preparation of a water-dispersible oleoresinous film-forming material comprises reacting a first hydroxyl group-containing oleoresinous film-forming material with an organic diisocyanate in an amount such that the ratio of isocyanate groups in the diisocyanate to hydroxyl groups in the oleoresinous film-forming material is about 2:1 to produce an adduct containing free isocyanate groups and subsequently reacting the adduct with a second hydroxyl group-containing oleoresinous film-forming material to form a diadduct containing the first oleoresinous film-forming material and the second oleoresinous film-forming material, one of said first and second oleoresinous film-forming materials being a relatively hydrophilic oleoresinous film-forming material and the other being a relatively hydrophobic oleoresinous film-forming material and the relatively hydrophilic oleoresinous film-forming material forming a minor proportion by weight, preferably from 5 to 20% by weight, of the total of relatively hydrophobic and relatively hydrophilic oleoresinous film-forming materials. The diisocyanate is preferably one in which one isocyanate group has a markedly greater reactivity than the other, such as isophorone diisocyanate. The invention also consists in paint comprising the resultant water-dispensible film-forming materials dissolved in a solvent therefor.
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