Preparation Of Photo-and Thermo-chromic Composite Materials And Their Application Research

Ultraviolet fluorescent polymeric material is a kind of polymer that can't show its fluorescent characteristic under visible light but can emit visible light when exposing to ultraviolet light. Thermochromism polymer is a kind of polymer whose color changed with the temperature. Both of these can be used as anti-counterfeit materials separately. But how to make full use of the merits of these two polymers and prepare photo-and thermo-chromic composite materials is a more promising way in Modern Anti-counterfeit Printing Technology.In this thesis we use polymers as reaction medium. Combine with laser holographic anti -counterfeit hot-pressure printing film Technology to prepare a new anti-counterfeit material that easy to detect. This thesis is consisted of two sections as follows:(1) Crystal violet lactone and bisphenol A are used as electron acceptor and donator respectively, polystyrene and acrylic resin are used as reaction medium, rare earth metal organic complex is used as fluorescent material to prepare photo-and thermo-chromic composite material. Its photochromism and thermochromism performance are detected by UV lamp and hot water respectively. When exposing under ultraviolet lamp, the composite material emit red fluorescent light, when douse by hot water(>70℃), the color of the composite material changed from blue to colorless. The influences of each component are also be discussed in this chapter.(2) Combing photo-and thermo-chromic composite material with laser holography Anti–counterfeit trademarks, PET Transfer Method is used to prepare photo-and thermo-chromic laser holography anti -counterfeit hot-pressure printing film. Its photochromism and thermochromism performance are also detected by UV lamp and hot water respectively. When exposing under ultraviolet lamp, the composite material emit red fluorescent light, when douse by hot water(>70℃), the colour of the composite material changed from blue to colorless. The influences of each technological parameters to the film and the cost are also discussed in this paper. To the same level of thermochromism and photochromism, our optimized hot-pressure printing film need only 1/30 ultraviolet fluorescent powder compared to former hot-pressure printing film, which greatly reducing the cost.