Microcapsules, a method for the production of the microcapsules and their use in pressure-sensitive aufzeichnungsblaettern

摘要

PURPOSE:To obtain a fine capsule which is excellent in physical properties and suitable especially for pressure sensitive copying paper by forming a capsule wherein amine-aldehyde polycondensation product is made to a wall film in a system consisting of both a specified copolymer anionic water soluble high molecule and a hydrophobic core substance. CONSTITUTION:A capsule is formed with a component consisting of (A) a copolymer anionic water soluble high molecule obtained by polymerizing preferably 73-92wt% acrylic acid, 2.5-17wt% styrene sulfonic acid and 2.5-22wt% =6C (meth)acrylic acid alkyl and (B) a hydrophobic liquid of a core substance and (C) amine (e.g. urea or the like) or aldehyde forming a wall film or these primary condensates. In other words, after diluting component (A) with city water, a continuous phase is made by dissolving component (C). Thereafter component (B) is added to this continuous phase while stirring component (B) and the mixture is emulsified. When a prescribed emulsified grain is obtained, pH is regulated and it is heated to form a capsule.