Painting Molded Polyurethane

Question:

Do you have information concerning the painting of urethane? The urethane is thin-skinned with a grain surface. I need to know what type of paints can be used? Does urethane need to have a cure time prior to painting? What solvents can be used to remove mold release? Thank you for any assistance. T.K.

Answer:

Since its use has increased dramatically over the past several years, molded polyurethane is being painted with a variety of paint types. If the molded part will flex in use, flexible coatings such as vinyl or polyurethane enamels would be prescribed. Otherwise, most of the commercially available paints will adhere.

As far as a "cure time" prior to painting, all products must be cured before painting. Molded polyurethane, as received, will be already cured and will require no further curing. These products are generally fully cured when they come out of the mold.

Removing mold release from molded products before painting can be a problem. Naturally, it must be removed to ensure paint adhesion. I generally suggest that the finisher contact the manufacturer of the mold release to get his recommendation for a solvent to remove his mold release.