White electrically conductive primer composition and method for forming multilayer coating film

A white conductive primer coating composition comprising:

• (a) 100 parts by weight of a resin mixture of a chlorinated polyolefin resin with a chlorine content of 10 to 40 wt. %, and at least one modifier resin selected from the group consisting of acrylic resins, polyester resins and polyurethane resins;
• (b) 5 to 50 parts by weight of a crosslinking agent;
• and
• (c) 10 to 250 parts by weight of a white conductive titanium dioxide powder which comprises titanium dioxide particles having on their surfaces a conductive layer comprising tin oxide and phosphorus, and in which the content (A) of metallic elements with valencies of 4 or less contained as impurities is no more than 0.1;
• the content (A) being calculated by the following formula (1)
• (A)=(M1)×(4−n1)+(M2)×(4−n2)+(M3)×(4−n3)+(M4)×(4−n4)+ . . . +(MX)×(4−nX) Formula (1)
• wherein M1, M2, M3, M4, . . . MX are the atomic ratios of metallic elements with valencies of 4 or less to Sn of the tin oxide in the white conductive titanium dioxide powder;
• n1, n2, n3, n4, . . . nX are the valencies of metallic elements having atomic ratios of M1, M2, M3, M4, . . . MX, respectively;
• and X in MX and nX is the number of such metallic elements contained in the white conductive titanium dioxide powder, and may be a natural number 1 or more.