ARB Research Seminar
This page updated June 19, 2013
Correlation between Solids Content and Hiding as it Relates to Calculation of VOC Content in Architectural Coatings
Albert Censullo, Ph.D., California Polytechnic State University
June 30, 2005
Cal EPA Headquarters, 1001 "I" Street, Sacramento, CA
A set of experiments was designed and conducted to investigate the effect of volume and type of solids on coverage and hiding for water-based and solvent-based architectural coatings. The experimental design was implemented by formulating 30 water-based and solvent-based coating samples with varying amounts and types of pigments and resins. Thirty unique formulations were prepared corresponding to coatings commonly used in California. Coating classes included flat, eggshell, semigloss and gloss. Once formulated in agreement with the experimental design, the coatings were applied to well-defined surfaces, and evaluated by a series of standard tests for coverage, film thickness, hiding, and color, as appropriate to the coating type. The relationship between hiding and solids content was determined for each of the 30 coatings and for each coating category. These relationships were used to evaluate the usefulness of using the actual VOC content (VOCactual) and the regulatory VOC content (VOCregulatory) of a coating as metrics for specifying the VOC content of coatings. In addition, a new metric for specifying the coating's VOC content was developed. This metric includes both the amount of VOC in the coating and the coating's hiding ability, and is referred to as the "Hiding VOC" or VOCH0.98.
Albert Censullo, Ph.D., is Professor of Chemistry in the Department of Chemistry and Biochemistry at California Polytechnic State University, San Luis Obispo. Dr. Censullo received his Ph.D. in Analytical Chemistry from Penn State University. Dr. Censullo has authored a number of publications on the analysis of the composition of architectural and aerosol coatings and on the development of species profiles for architectural coatings.