Breathing epoxy powder coating

Abstract

The invention discloses a permeable epoxy powder coating, belonging to the field of powder coating technique of static coating. According to the weight percentage of the formula, the coating takes 25-30 percent of epoxy resin, 10-20 percent of novolac epoxy resin, 8-20 percent of phenolic curing agent, 0.8-5 percent of leveling agent, 1-20 percent of pigment, degasifying agent, other auxiliary agents and filling material as the raw materials and is prepared by the production process of the existing powder coating. The coating is characterized in that the degasifying agent is any one of polyethylene wax MPP230F, MPP230VF, MPP230XF, MPP620F, MPP620VF and MPP620XF and occupies 0.1-0.8 percent of the total weight. The permeable epoxy powder coating has outstanding degasifying effect and is widely used for the powder coating disposal of devices such as castings. The surface of the coating is flat and smooth. The construction performance and excellent internal quality are good.

Description

technical field [0001] The invention relates to a gas-permeable epoxy powder coating, which belongs to the technical field of electrostatic coating powder coatings. Background technique [0002] Powder coatings have been widely used and developed at home and abroad. In powder coating, problems such as the presence of pores in the substrate (such as castings) or improper pre-treatment processes (such as galvanizing, phosphating) on ​​some workpieces often lead to Obvious bubbles, shrinkage cavities, pinholes or particles appear on the surface of the coating, which seriously damages the decorative and aesthetic effect of the coating surface, and even endangers the anti-corrosion life of the coating. [0003] Air-permeable powder coatings are mainly functional powder coatings composed of resins, fillers and degassing additives. They have good degassing function and smooth surface of the coating film. They are suitable for cast iron, cast aluminum, hot-rolled plates and other se...

AI Technical Summary

Problems solved by technology

Benzoin is widely used in general powder coatings, but its degassing effect is weak. For the above-mentioned castings and other workpieces, its degassing effect is very poor, and it is difficult to remove the gas that enters the molten coating from the inside of the substrate in a timely and effective manner. , the coating still has significant defects such as bubbles, shrinkage cavities, and particles

[0005] In recent years, some manufacturers have introduced a lot of degassing agents, such as domestic SA500 degassing agent, foreign PW-188, etc. The above degassing agents can effectively replace benzoin in ordinary powder coatings, although the yellowing of the color is avoided. Insufficient, but it is also difficult to efficiently remove a large amount of gas contained in the molten coating, and cannot guarantee the decorative effect of the coating surface of castings