Cationic electrodeposition coating composition and a process for preparing the same

• Main Authors: Song, Ki-Myong, Hong, Jong-Myung, Chung, Hoon, Back, Seung-Jae
• Format: Patent
• Language: English
• Published: 16.04.2002

The present invention relates to a novel cationic electrodeposition paint composition and a process for preparing the same, and more particularly to a cationic electrodeposition coating composition in which the electrodeposited coating film of the electrodeposition paint composition has an epoxy-acrylic double-layered structure, and in which an organic solvent content can be minimized, and a process for preparing the same. Further, the present invention relates to a pigment grinding vehicle suitable for electrodeposition coating of the cationic electrodeposition paint composition. Disclosed are a cationic electrodeposition coating composition and a process for preparing the same in which the dried coating film of the electrodeposition paint has an epoxy-acrylic double-layered structure for displaying excellent properties, and in which an organic solvent content can be minimized. The cationic electrodeposition coating composition having a resinoid dispersed into an aqueous medium comprises a cationic electrodeposition resin and an organic solvent of less than 2.0 percent by weight based on a dispersed solution of the cationic electrodeposition resin. The cationic electrodeposition resin can be manufactured by means of a mixture comprising (i) 40-60 percent by weight of a cationic electrodeposition synthetic resin which is obtained by an epoxy-amino addition reaction, (ii) 5-10 percent by weight of an acrylic cationic electrodeposition synthetic resin having an amino group, (iii) 1-3 percent by weight of a fatty acid ester resin synthesized by an ester exchange reaction of styrene-arylalcohol copolymer and fatty acid, and (iv) 30-50 percent by weight of a blocked polyisocyanate crosslinking agent. The coating layer formed by means of the electrodeposition coating has improved properties with respect to an appearance, weather resistance, yellowing resistance, and hardness.