Causes and solutions for discoloration of paint

The varnish was originally a clear, colorless or extremely pale yellow, which turned brown or black after discoloration. Then the cause and solution of the discoloration of the paint is known. Everyone knows that the paint also has a discoloration phenomenon, mainly because the color of the paint with a light color becomes darker.

The reasons for the discoloration of the paint may be as follows:

(1) The ester solvent in the varnish reacts with the iron container and becomes black after being exposed to water.

(2) Turpentine oil easily produces reddish brown pigment in iron drums.

(3) Gold and silver powder and varnish are prone to acid etching, making the paint color green, dark, and tarnished.

(4) The storage period is too long and the sediment is discolored.

The prevention and control method is:

(1) The shellac varnish which is most prone to discoloration is contained in a non-metallic container.

(2) Add gold powder and silver powder before using varnish. Do not prematurely add it to varnish for storage.

(3) If the coating is discolored, if it is not a quality problem, it can be used after thorough stirring.