Polymerized fatty acid polyamide resin dispersions and method for the manufacture thereof

Abstract

A method is provided for the preparation of stable aqueous dispersions of non-solvated, un-neutralized, low amine, low acid number polymerized fatty acid polyamide resins. In the preferred method of this invention, a polymerized fatty acid polyamide resin which has been prepared so as to have a low acid and low amine number is liquified by heating the polyamide resin to a temperature where it is at or above its melting point. The liquified polymerized fatty acid polyamide resin is then blended with a predetermined amount of water which is heated to a temperature such that the resulting blend will have a temperature above the melting point of the polyamide resin. A surfactant which will promote the emulsification of the polyamide resin and water is included in the mixture. The resulting mixture is then subjected to sufficient comminuting forces to form an emulsion in which droplets of the polyamide resin have a volume average size distribution of about 20 microns or less in diameter and preferably 5 microns or less. The resulting emulsion is then cooled to a temperature below the melting point of the polyamide resin causing the emulsified droplets of the polyamide resin to solidify as finely divided particles which are dispersed uniformly through the aqueous phase. The resulting stable aqueous dispersions of the polymerized fatty acid polyamide resin which are obtained are especially useful for hot melted adhesive applications, and when utilized in coatings, inks, and the like.

Dependencies are inferred from the claim text.