Laser beam absorbing resin composition and laser beam marking method
AssigneeSomar Corporation
InventorsJun Takahashi, Akira Yasuda, Hideo Ochi
Life of this patent
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Abstract
A laser beam absorbing resin composition is disclosed which includes 100 parts by weight of a thermosetting resin, a colorant capable of discoloring upon being heated at a temperature of 250.degree. C. or more, and at least 10 parts by weight of a particulate, laser beam absorbing substance which has an average particle size of 50 .mu.m or less and which is at least one member selected from cordierite and zeolite. By irradiating a shaped, hardened body of the above composition with a laser beam, the colorant is thermally decomposed, so that the color of the irradiated surface is changed and becomes discriminitive from that of non-irradiated surface.
Claims29
A composition for marking by irradiation with a carbon dioxide or YAG laser beam, said composition comprising 100 parts by weight of a thermosetting resin, a colorant capable of discoloring upon being heated at a temperature of 250.degree. C. or more, and at least 10 parts by weight of a particulate, laser beam absorbing substance which has an average particle size of 50 .mu.m or less and which is at least one member selected from cordierite and zeolite;
- and wherein said colorant comprises a first, white substance which is converted into a second, white substance different from said first substance upon being heated at a temperature of 250.degree. C. or more, said composition further comprising an auxiliary colorant which is inert to laser beam irradiation and which has a color other than white.
A composition for marking by irradiation with a carbon dioxide or YAG laser beam, said composition comprising 100 parts by weight of a thermosetting resin, a colorant capable of discoloring upon being heated at a temperature of 250.degree. C. or more, and at least 10 parts by weight of a particulate, laser beam absorbing substance which has an average particle size of 50 .mu.m or less and which is at least one member selected from cordierite and zeolite;
- and wherein said colorant comprises:
- a first, white substance which is converted into a second, white substance different from said first substance upon being heated at a temperature of 250.degree. C. or more, and a third substance which shows a color other than white at room temperature and which becomes colorless upon being heated at a temperature of 250.degree. C. or more.
A composition for marking by irradiation with a carbon dioxide or YAG laser beam, said composition comprising 100 parts by weight of a thermosetting resin, a colorant capable of discoloring upon being heated at a temperature of 250.degree. C. or more, and at least 10 parts by weight of particulate cordierite as a laser beam absorbing substance, said particulate cordierite having an average particle size of 50 .mu.m or less;
- and wherein:
- said colorant comprises a first substance showing a first color at room temperature and convertible to a second substance having a second color different from said first color upon being heated at a temperature of 250.degree. C. or more.
A composition for marking by irradiation with a carbon dioxide or YAG laser beam, said composition comprising 100 parts by weight of a thermosetting resin, a colorant capable of discoloring upon being heated at a temperature of 250.degree. C. or more, and at least 10 parts by weight of particulate cordierite for laser beam absorption, said particulate cordierite having an average particle size of 50 .mu.m or less, wherein said colorant is at least one member selected from the group consisting of copper oxalate, cobalt oxalate, aluminum acetylacetone, bismuth oxalate, silver acetate, metal titanates, basic nickel carbonate, basic copper carbonate, bismuth oxide, ferric hydroxide, ammonium vanadate, hydrated alumina, zinc borate, zinc carbonate, lead oxide, basic lead phosphite, basic lead sulfite, basic lead phosphite sulfite, lead phosphite, lead sulfite and organic dyes.
Dependencies are inferred from the claim text.