X-Ray CT Measurements of Ink Penetration Area in Inkjet Printing With Pigment Ink

Abstract

Penetration control based on penetration theory is important for inkjet printing because ink penetration affects print quality and productivity. However, existing theories of pigment ink penetration are many unanswered questions regarding the penetration behavior inside the media. In this study, three-dimensional penetration shapes of two types of pigment inks with different particle sizes onto three types of porous polyimide films were measured by X-ray CT (computational tomography) to elucidate the influence of media void size, hydrophilicity, and pigment particle size. The results showed that when the media void size was larger than the pigment particle size, the stronger the capillary force of the media, the more pigment particles densely penetrated into the media. Under conditions where the media void size and pigment particle size are almost equal or smaller, penetration is suppressed because pigment particles tend to clog the void space.