PURPOSE: To easily obtain diversified coloring states by sealing a color former and coloration inducing agent in the state of isolating the same by a hot- meltable resin into a microcapsule and mixing the same by heating, thereby forming the color.

CONSTITUTION: The color former 4 is sealed between the microcapsule 2 formed by a transparent heat resistant resin and the microcapsule 3 formed of the hot-meltable resin sealed therein and the coloration inducing agent 5 is sealed into the microcapsule 3. A color forming layer is then formed at a prescribed thickness on the surface of the base material 6 and the color forming particle 1 in the layer 7 are heated by a laser, etc. Then, the temp. of the microcapsules 2, 3 of the particle 1 increases and the color former 4 and the coloration inducing agent 5 are brought into the mixed state. The diversified colored states are thus easily obtd.