| 摘要 |
PURPOSE:To enable a black color to be sharply recorded by using a black toner having a reflectance satisfying specified conditions, when white paper is coated in a specified thickness with a black toner obtained by blending >=2 kinds of pigments or dyes transmitting light in the wavelength region of >=750nm. CONSTITUTION:The black toner to be used has spectral characteristics having a reflectance of <=5% in the total visible light wavelength region and a reflectance of >=40% in the >=750mum wavelength region by using the noncoated white paper as the basis, when the white paper is coated in a thickness of 10-20mum with the black toner obtained by blending >=2 kinds of pigments or dyes transmitting light in the wavelength region of >=750nm. The black toner is prepared not by using a single colorant, such as carbon black, but by mixing plural colorants, such as yellow, magenta, and cyan colorants, and each of these colorants transmits light in the nonvisible wavelength region, and the obtained mixed colorants transmits light in the nonvisible wavelength region, and substantially and completely absorbs the visible light, thus permitting the obtained black toner to sharply record the black parts and the colored parts in good balance. |
