After the coating is dried, a smooth dry paint film cannot be formed, but a concave-convex phenomenon with the appearance of orange peel.
cause:
(1) The thinner of the paint evaporates too fast, and the ambient temperature of the coating construction is too high or too low;
(2) The coating is too thick or too thin, or the bottom layer is not effectively cured;
(3) The leveling property of the coating itself is poor, and the viscosity of the coating is high;
(4) The air velocity in the roller coating room is too high or the temperature is too high;
(5) The temperature curve of the curing furnace is not set properly, so that the wet coating enters the high temperature zone prematurely after entering the furnace;
(6) The type of bottom coating does not match.
Method of exclusion:
(1) Select the paint varieties that match between the substrate and the coating, and between the base coat and the top coat;
(2) Use an appropriate thinner to reduce the construction viscosity of the coating on the machine;
(3) The primary coating should not be too thick, and the top coat should be applied after the undercoat is completely cured;
(4) Reduce the ventilation speed in the roller coating room;
(5) It is better for the wet coating to enter the curing furnace after a period of air leveling. The temperature setting of the furnace should be gradually increased from low temperature to high temperature, and sudden temperature rise should not be avoided.
