| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an oily pigment ink composition comprising a pigment, an organic solvent and a polymeric compound, capable of attaining printer reliability, e.g. continuous mass printing for printed matter of stable quality through improving jet stability of its own in conducting a high-speed printing with a drive frequency of 10 KHz or greater, and also capable of printing on a printing medium made of an inexpensive film such as of polyvinyl chloride with no ink-receiving layer, and withstanding outdoor service circumstances. <P>SOLUTION: The oily pigment ink composition essentially comprises a pigment, an organic solvent and a polymeric compound. This oily pigment ink composition is 1-30 mPa s in viscosity B and 1.01-1.40 in thixotropy modulus: viscosity B/viscosity A, wherein the viscosity A and the viscosity B are such as to be determined at shearing rates of 1×10<SP>3</SP>sec<SP>-1</SP>and 1×10<SP>4</SP>sec<SP>-1</SP>at 25°C, respectively, by a method using a rotational viscometer involving shearing rate increase. <P>COPYRIGHT: (C)2008,JPO&INPIT |
