Covering light issue - pinholes Brush marks

pinhole

Circular small circles appear on the mask, resembling pinprick holes; It looks like a big bump.

① It is caused by the rapid swirling evaporation of the solvent during the initial stage of film formation, resulting in incomplete leveling of the paint film. This defect often occurs after high-temperature drying.

② Improper solvent selection and excessive use of low boiling point solvents that are prone to drying.

③ Poor operation. Uneven stirring, thick coating or water infiltration are also reasons for the formation of pinholes.

Brush marks

The brush marks left by the glossy film coating still exist after drying.

① Coatings with high viscosity and fast solvent evaporation are prone to brush marks.

② Nitro coatings and acrylic coatings, due to the rapid evaporation of solvents, may produce brush marks even if the viscosity is low when applied by brushing,

Therefore, this type of coating is not suitable for brushing.

③ Using a hard bristled brush is also one of the reasons for producing brush marks. It is advisable to use a soft bristled brush.