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Thermal transfer printing technology is gradually used by people who love DIY very much, thermal transfer printing paper as the carrier of transfer printing technology directly dominate the quality of the technology. At present, domestic thermal transfer paper has a lot of defects such as paper’s shape change, paper’s size un-steady, low absorb ability of ink, low transfer ability, dissimilarity of image, low picture’s reducibility, also, after transferred, the coat can easily be removed by washing, sunshine or friction. By comparison, overseas thermal transfer paper has excellent performance, but the price is higher than home-made paper, so, it is urgent need to resolve the defects of domestic thermal transfer paper. The basic paper, the coating, the coating’s structure and function of the paper, thecomponent of the coating are all studied in this paper, to seek for the best technology of high color thermal transfer paper, the paper is divide into 4 layers: the basic paper, the abhesive layer, transfer layer, ink absorption layer. Every layer has its special property, the structures and properties of transfer layer and ink absorption layer are primary studied. The specific work and the main results of the article include the following parts:1 high fixed quantity paper which contains fifty percent chemical pulp and fifty percent mechanical pulp is chose as basic paper of high color thermal transfer paper, use corona discharge to deal with the basic paper and make it polarization, so it can be easier coated. Use PVA to coat basic paper in order to coat abhesive agent further.2 The abhesive layer is mainly made up by silicones abhesive agent, some special catalyst, cross linker and firming agent are added into the agent to make the layer have a better performance. The layer’s coating weight is 4 g/m~2, the solidification value is 150℃, solidification time is 35 min, under this condition, the performance of the abhesive layer is optimally.3 the transfer layer is mainly composed by TPU and PET. The coating weight is 8 g/m~2, the ratio of TPU and PET is 7:3, the transfer temperature is no lower than150℃, under this condition the transfer rate of transfer layer is 94.7%, SEM pictures show that the structure of transfer layer is compact and the layer is wear resistant.4 The dope of ink absorption layer is composed by adhesive, pigment, dispersant, fixed agent and other agents. PVA and SBR are used as adhesives which ratio is 6:4, and the addition is 25 parts by comparison with pigment which addition is 100 parts. The pigment is composed by HP-1055 and nm SiO2, which ratio is 7:3, the added ratio of dispersant and fixed agent is 1% and 2% respectively, the ink absorption layer can transfer 94.1 percent ink onto the stock under 160℃.5 Through the SEM and IR it can be seen that the lab-made thermal transfer paper has better performance in ink absorption ability, image fidelity ability, print colour density and transfer rate than domestic thermal transfer paper.
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