Black Pigment Composition
AssigneeClariant International Ltd.
InventorsDaisuke HARADA, Yuya ICHIHARA
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AssigneeClariant International Ltd.
InventorsDaisuke HARADA, Yuya ICHIHARA
Estimating the term…
The invention provides a black pigment composition capable of overcoming the drawbacks of carbon black pigments, which, when used as a toner colorant in particular, is able to reduce color shading over time and improve image qualities through an improvement in charging performances such as charge leakage and the like. The invention also provides a chromatic pigment composition able to reduce and correct the tinge of a carbon black pigment while improving fading stability, when the composition is added to a carbon black composition for electrophotographic toners. The black pigment composition contains, as essential pigments, a pigment P1 having a maximum absorption wavelength λmax (nm) within the range of 460≦λmax≦530 and a half-value wavelength (long wavelength side) of the absorption spectrum of 550 nm or more, and a pigment P2 having a maximum absorption wavelength λmax (nm) within the range of 600≦λmax≦700, as measured in the form of a dispersion in a solvent (methyl ethyl ketone).
A black pigment composition, comprising, a pigment P1 having a maximum absorption wavelength λmax (nm) within the range of 460≦λmax≦530 and a half-value wavelength of the absorption spectrum (on the long wavelength side) of 550 nm or more, and a pigment P2 having a maximum absorption wavelength λmax (nm) within the range of 600≦λmax≦700, as measured in the form of a dispersion in a solvent.
Dependencies are inferred from the claim text.