Rubtests

Rubtests refer to a family of standardized procedures used to evaluate how materials respond to rubbing or friction. They are applied across coatings, textiles, elastomers, plastics, and metal finishes to assess wear resistance, surface integrity, and, in textiles, colorfastness. The central aim is to simulate repetitive contact conditions and produce quantitative data that can be used to compare materials or to guide formulation and finishing decisions.

In methodological terms, rubtests typically involve mounting a specimen in a rubbing apparatus that drives a pad, brush, or abrasive medium against the surface under a defined load and motion. Tests run for a prescribed number of cycles or time, after which measurements are taken. Common outputs include mass loss or volume wear, changes in thickness, surface roughness, microscopic or visual assessment of damage, and, for color-sensitive materials, color change or dye transfer. Some variants also record the coefficient of friction during testing.

Variants of rubtests address different use conditions. Dry rubbing uses air or inert media, while wet rubbing introduces moisture, solvents, or lubricants to simulate real-world environments. In textiles, crocking or colorfastness to rubbing is a prominent application, whereas coatings and floor materials may emphasize abrasion resistance or scratch propensity. Instrumented versions often employ devices similar to Taber-type testers or custom rubbing rigs to improve repeatability.

Standards and quality control practices guide rubtests, with laboratories adapting procedures to reflect specific applications and field conditions. While lab results provide valuable comparative data, they are not absolute predictors of long-term service performance due to variability in media, pressure, speed, and environmental factors.

See also: Abrasion resistance, Taber abrasion test, Crocking, Colorfastness.