Study On Photosensitive And Thermal Response Microcapsule Information Recording Material

To record and then re-display target information, photosensitive and thermal response microcapsule information-recording material is mainly based on encapsulated thermal sensitive dye. Microcapsule provides dye an isolated circumstance and records information through irradiation with certain wavelength. When being developed, different release capabilities between non-irradiated microcapsules and irradiated ones lead to image. Because it can be developed in dry state and under sunlight, and the developing process is very convenient, this kind of material has a promising future in application. In this project, two different kinds of photosensitive and thermal response information-recording materials are designed, and further study is pursued on their preparation and recording properties. The related work is as follows:Ethoxylated pentaerythritol is esterified by acrylic acid to get photosensitive double bond, and then reacts with diisocyanate to prepare oligomer of shell. Through interfacial polymerization, the oligomer can form into photosensitive shell of microcapsule. According to comparison of microcapsules’morphology and diameter-distribution, a satisfying condition for preparation has been obtained:Mol ratio of diisocyanate and photosensitive ester is3:2to prepare oligomer of shell; Oily phase is distributed in5wt%PVA aqueous solution with rotate speed of3000rad/min; mass ratio of aqueous phase and oily phase is4:1. The microcapsule can be made into recoding material and the satisfying condition for development is obtained basing on difference of lightness between non-irradiated areas and those irradiated:keep heating for5min under130℃.Anohter microcapsule system is formed with polyurea as shell and photo-curable resin as core. Release property of the microcapsule can be controlled by photo curing react and lead to image. The satisfying condition for process has been obtained by comparison of lightness differences between non-irradiated areas and irradiated ones:concentration of dye is2wt%; concentration of dye’s coupler is CD; time period of irradiation is ti, developing temperature is T; time period of heating is tp. Such a system has the same recoding function as the microcapsule system mentioned above and possesses more value of application.