Let us First explain the process of discoloration testing. The test starts by creating samples. In testing Watercolors or Oriental Colors, the samples are created with a 1-to-1 ratio of the experimenting paint and water. It is important not to leave brush marks while coloring. For Acrylic Colors, samples are created by coloring with an even thickness of 90㎛ using an applicator. The experimenting colors are painted side by side with the colors to compare with. Half of the painted samples are covered after they have been completely dried. Then the samples are placed into an up-to-date discoloration simulator. The simulator beams the exposed portions of the samples to rays of ablout 4000 times of that of the sunlight energy and hence one hundred hours inside the simulator is equivalent to about 45 years in real life.