METHOD OF FORMING MULTILAYER ELECTRODEPOSITION COATING FILM

摘要

PROBLEM TO BE SOLVED: To obtain a color multilayer coating film having a under layer formed from an anionic electrodeposition coating material (B) containing a color pigment and an upper layer formed from an anionic coating material (A) containing no color pigment without contaminating a bath for the anionic electrodeposition coating material (A) containing no color pigment. SOLUTION: In a method of forming the multilayer electrodeposition coating film which is carried out by electro-depositing the anionic electrodeposition coating material (A) containing no color pigment to form an uncured electrodeposition coating film on a material to be coated and next, electrodepositing the anionic coating material (B) containing the color pigment to form an electrodeposition coating film (B1) based on the (B) and to form an electrodeposition coating film (A1) on the (B1), the temperature for forming the minimum continuous coating film is 10-22°C, a bath temperature in the electrodeposition coating for the (A) is equal to or below the temperature for forming the minimum continuous coating film, a bath temperature in the electrodeposition coating of (B) is 20-35°C and is 5-35°C higher than that in the electrodeposition coating of the anionic electrodeposition coating material (A). COPYRIGHT: (C)2006,JPO&NCIPI