首页>
外国专利>
Microcapsules containing oils and soluble color reaction components, their manufacture and use in color reaction recording systems
Microcapsules containing oils and soluble color reaction components, their manufacture and use in color reaction recording systems
展开▼
机译:含有油和可溶性显色反应成分的微囊,其制造及在显色反应记录系统中的使用
展开▼
页面导航
摘要
著录项
相似文献
摘要
A process for microencapsulating hydrophobic oils with color reactants, dissolved therein, of color reaction systems by reacting a water-soluble non-ionic melamine/formaldehyde precondensate and a water- soluble polymer in an oil-in-water dispersion for forming the capsule envelope is described. The special feature of this process is that, for stabilizing the oil-in-water dispersion, an aqueous solution of a cationic melamine/formaldehyde precondensate and the aqueous solution of a water- soluble polymer are mixed with vigorous stirring, a solid precipitating as a very fine suspension in the mixture, the mixture thus obtained and containing the very finely suspended solid is mixed with ther oil, containing the color reactant in solution, with vigorous stirring, the oil-in-water dispersion thus obtained in acidified and an aqueous solution of a water-soluble non-ionic melamine/formaldehyde precondensate is added with stirring, in order to form the capsule envelope. The use of the cationic melamine/formaldehyde precondensate leads to the precipitation of a very finely suspended reaction product thereof, whereby all the reaction systems in the course of the process are stabilized. Excellent capsules can be obtained without formation of agglomerates. The invention also relates to the microcapsules obtainable by the above process and to their advantageous use in color reaction recording systems.
展开▼