| abstract |
Aqueous dispersions of polyamide resins having improved stability with respect to gelation and phase separation are provided, along with preparative methods therefor. The improved stability of the provided aqueous dispersions is achieved by the addition to such dispersion of a chemical moiety, such as a water soluble, amphoteric amino acid, anionic and cationic salts of amino acid, or mixtures thereof, in aqueous solutions. In a preferred embodiment, a dispersion-stabilizing amount of glycine is added with the inversion water used to invert an emulsion of water in polyamide resin. The resulting emulsion of resin in water is then cooled below the resin's melting point, causing the emulsified droplets of the polyamide resin to solidify as finely divided particles which are dispersed uniformly through the aqueous phase. The stable, aqueous dispersions of this invention are useful in coatings, inks, and as coatings for hot melt adhesive applications. |