Carbon Black for Waterborne Coatings

摘要

An aqueoue carbon black millbase, an aqueous carbon black liquid coating, and a method of making the millbase and liquid coating are provided. The carbon blacks are modified carbon blacks that are engineered to be able to be stirred into an aqueous vehicle without high energy milling of the carbon black. The modified carbon blacks include low organic treatment levels and the millbase and liquid coating do not require large quantities of dispersant. The resultant coatings exhibit excellent viscosity, color, hiding power and stability.

主权项

1. A carbon black millbase dispersion comprising:
an aqueous solvent comprising greater than 90% water by weight; at least 30% by weight of a modified carbon black, the modified carbon black having an STSA between 20 and 300 m2/g as measured prior to treatment, the modified carbon black modified with a treating agent comprising an organic group and an ionic or ionizable group at a treating agent concentration of between 1.0 and 3.0 μmol/m2; a dispersant concentration of less than 2.4 mg per square meter of carbon black surface area as measured by STSA prior to treatment; and wherein less than 10% by volume of the carbon black dispersed in the millbase has a particle size of greater than 0.5 μm.