Stamp ink and stamp ink impregnation pad for stencil printing

摘要

A stamp ink, for stencil printing, is made from a coloring-agent mixed in a vehicle made from resin and oil-based solvent. The stamp ink has a viscosity in a range from 20 to 250 poises at a shear rate of 20/sec under temperature of 25 DEG C. and has a thixotropy index T.I. in a range from 1.2 to 3.0 under temperature of 25 DEG C. where the thixotropy index T.I. is defined in the expression of: T.I.=(Viscosity at a shear rate of 0.5/sec)/(Viscosity at a shear rate of 5.O/sec).