High-chroma C.I. Pigment Red 254 and process for producing the same
AssigneeDIC Corporation
InventorsHirotsugu Nemoto, Shousaburou Tanaka, Takashi Sato
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AssigneeDIC Corporation
InventorsHirotsugu Nemoto, Shousaburou Tanaka, Takashi Sato
Estimating the term…
The present invention relates to C. I. Pigment Red 254 for coloring, which can color an object to be colored so as to have a higher chroma than that with conventional technology and a production method for easily producing it. For the purpose, the inventors provide the production method for the pigment, wherein the intersection of mass tone ΔH* and ΔC* of a color coating film in an acrylic-melamine coating test is, on X-Y coordinate plane to which the ΔH* is defined as the X-axis and the ΔC* is defined as the Y-axis, within the surrounded region determined by specific three equations; and a production method for the pigment provides the production method of the pigment, including a process of heating crude pigment at 100-130° C. for 2-10 hours in an aprotic polar organic solvent which is strongly alkaline.
C. I. Pigment Red 254, wherein the ΔH* and ΔC* of a color coating film in an acrylic-melamine coating test is within a surrounded region determined by following three equations:
C. I. Pigment Red 254, wherein the ΔH* and ΔC* of a color coating film in an acrylic-melamine coating test is within a surrounded region determined by following three equations:
A production method for C. I. Pigment Red 254 having a mean particle diameter of 0.30-0.80 μm comprising heating 1,4-diketo-3,6-bis(4-chlorophenyl)pyrrolo[3,4-c]pyrrole having mean particle diameter of 0.10-0.20μm in a strong alkaline aprotic polar organic solvent at 100-130° C. for 2-10 hours, further comprising the step of, heating the 1,4-diketo-3,6-bis(4-chlorophenyl )pyrrolo[3,4-c]pyrrole at 100-130° C. in neutral or weaker alkaline aprotic polar organic solvent prior to heating in the strong alkaline aprotic polar organic solvent.
Dependencies are inferred from the claim text.