酸敏变色记录材料光化反应的研究

本文研究了一种由含卤共聚物和酸敏指示剂所组成的记录显示材料的光化反应,阐明了其成象过程中主要光化反应的机理,并对加入酸性添加剂,改善图象稳定性作了试验和讨论。

A STUDY ON THE PHOTOCHEMICAL REACTIONS OF THE ACID SENSITIVE COLOUR-CHANGING MATERIALS

An acid sensitive colour-changing material,composed of halogenated copolymer and acid indicator,has been developed. In order to improve its image quality,the photochemical reaction involved was studied. It was shown that the VDCl₂-MA undergoes a simple process of photolysis with the release of HCl,based on -the spectral characteristics of VDCl₂-MA copolymer before and after exposure to UV irradiation and the ESR and ESCA measurements upon exposure to UV. The experimental results show that upon UV irradiation the tran-form DMY is converted into cis-form,and the cis-form is unstable and turns back easily into the trans-form when the irradiation is ceased. The rate of the reverse reaction follows the first order kinetics and the rate constant is 1.1×10^-2 sec^-1,measured by flash photolysis. The image recorded by the VDCl₂-MA and DMY photographic materials undergoes some fading in storage. By the addition of phenols,the image stability was improved.