Effect of Dye Amount on the Image Density Property of Heat Sensitive Microcapsule Material

摘要

Microcapsule material can be controlled to perform various functions based on its unique response characteristics to certain environmental conditions, such as mechanical, chemical or electrical stimulus. In information-recording field, the applications of pressuresensitive and heat-sensitive microcapsules have basically matured. With the development of the technology, higher requirements on stability of image density are put forwards for the digital information recording materials. In this paper, the effect of encapsulated dye amount on image density is explored. Based on interfacial polymerization technique, optimal synthesis parameters are decided, with which the heat sensitive microcapsule size has been controlled as around 400nm. Such an average size reaches the level of the traditional silver halide information-recording microcrystal. Image property is the most important property of heat sensitive microcapsule. For the sake of the best stability of image density, the optimal ratio of developer and the microcapsules was obtained as 3.5:1.At this point, the shift of fog density is smallest as 0.05. Meanwhile, the relationship between dye amount and image density was obtained. Results indicated that the image density is affected by dye amount, since dye amount determined the image formation degree. Heat developing property study can provide precious data for the application of the heat sensitive microcapsules material.