MITRA Forum Question Details

​While there are food-grade defoamers available to consumers that are similar to those used in the paint industry, I hesitate to recommend them since the analogous materials for paints can affect adhesion and film integrity when added in incorrect amounts. Before modifying the paint/primer, I would test different rollers. Manufacturers of architectural/house paints give guidelines for the best type of roller to use for diluted paints so bubbles don't form, so I think it makes sense to try this first. 

Matthew Kinsey
Utretcht Art Supplies

Hi, our response would be along the same lines as those from Matthew Kinsey, from Utrecht.  In general water based materials are prone to the stabilization of foam, and in formulation defoamers are incorporated to reduce this issue as much as possible while not causing other surface defects. 

As far as prevention, it really comes down to technique. Foam rollers - in an ironic twist on their names - are notorious for foam generation, as their pores force air into paint with each compression.  A fine nap roller will reduce this greatly, but in general we recommend trying to avoid rolling altogether if wanting a relaiablly foam free surface. Sprayting will always be the gold standard in this area, and while we realize that would represent an investment and learning curve, if wanting a perfect surface, that is by far the way to go.

Hope this helps.

Sarah Sands
Senior Technical Specialist
Golden Artist Colors