CPC C09B 67/0097 (2013.01) [C09B 9/00 (2013.01)] | 5 Claims |
1. A method of preparing an electric and temperature dual-control bi-stable color changing microcapsules, comprising the step of:
(1) preparing a dual-control compound: heating and stirring an electric and temperature dual-control bi-stable color-changing dye to form a dual-control compound in uniform mixed solution; wherein the electric and temperature dual-control bi-stable color-changing dye, comprising a leuco dye, an electrolyte and an organic solid material, wherein the leuco dye is 2′-chloro-6′-(diethylamino)fluoran; the electrolyte is tetrabutylammonium perchlorate; the organic solid material is selected from the group consisting of stearyl alcohol, cetyl alcohol, myristyl alcohol, myristic acid, palmitic acid, stearic acid, glyceryl monostearate, glycerin monostearate, glyceryl laurate, p-azoxyanisole, diphenyl carbonate, phenyl salicylate, phenyl stearate and benzyl benzoate; and a ratio of the leuco dye to the electrolyte to the organic solid material is 1:2-10:15-50; and
(2) preparation of dual-control bi-stable microcapsules: dropwise adding the dual-control compound obtained in step (1) to an aqueous solution containing an emulsifier, the emulsifier accounting for 25-100% by mass of the dual-control compound, and carrying out high-speed emulsification to form a uniform dye dispersion; dropwise adding monomers accounting for 20-100% by mass of the dual-control compound to the dye dispersion, and continuing emulsification for 10-20 minutes; and then, transferring the emulsified dispersion into a four-neck flask with a reflux condenser and a stirring device, after introducing nitrogen for 5-30 minutes, raising a temperature to 55-75° C. at a stirring speed of 250-500 r/min, after reaching a reaction temperature, dropwise adding an initiator accounting for 0.1-1% of a total amount of the monomers, keeping the temperature to react for 2-6 hours, and after the completion of the reaction, washing a product with water and drying the product to obtain the dual-control bi-stable microcapsules.
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