Waterborne Paints Research Articles

Coatings Update: Pollution, toxicity, regulation and the paint industry: Part 2

An interesting article in the American Paint & Coatings Journal [February 18 (1980) p. 55] describes for the consumer how his choice of paints will change because of the desire of the California Air Resources Board to decrease the air polluting aspects of these products. The article points out that the consumer will either use more waterborne paints or he will use oil‐based paints with higher solids. One of the immediate observations the consumer will make about higher solids paints is that they cost more. This is to be expected, of course, since the vehicle is generally more expensive than the solvent. On the other hand, the consumer is cautioned not necessarily to expect better performance associated with higher price. For sure, it will probably cover more surface but, in fact, it may dry more slowly and be less durable, and the fact that it is thick will adversely affect smooth flow and tend to inhibit the disappearance of brush marks. Furthermore, the high‐solids paints will tend to have a hard, glassy, smooth finish which is difficult to reproduce in low‐solids paints. Also, the low solvent paints will not cover greasy and chalky surfaces as well nor will they adhere as well. Thus, surface preparation becomes very important. This is indeed an interesting article, for all too often the role of the consumer is neglected in the mad scramble for compliance.

Coatings update: scientific studies

The coatings industry is based on a large number of scientific principles. To be sure, it developed both in ancient and modern times without regard to these. But once an empirical body of knowledge was built up, it became obvious that theoretical underpinnings were not only desirable but necessary if progress were to be made. What are some of the scientific principles which govern coatings technology? Film formation is certainly one. What causes a film to form, and what affects the properties of a film such as cohesion, adhesion, gloss, flexibility, permeability, impact resistance, and a dozen other characteristics? The problem of understanding film formation became all the more important with the advent of waterborne paints, for polymer particles suspended in water are not nearly as prone to form films as are polymer solutes in a solvent.

Rheological aspects of the hardening of water-borne alkali silicate zinc-rich paints

The kinetics of the reaction between zinc dust and alkali silicate in water-borne silicate zinc-rich paints was investigated on the basis of rheological measurements. The paints studied were formulated with the same zinc dust/silicate vehicle ratio. Different zinc dusts were employed. The vehicle was a litiumsodium silicate solution. Formulation included a rheological agent to prevent rapid settling of suspended zinc dust.

Water-borne acrylic emulsion paints

Water-borne acrylic emulsion paints