Electroless gold plating bath, electroless gold plating method and electronic parts

1242 2242n4 1 4 322423222224242242422222422422 24242An electroless gold plating bath includes a water-soluble gold compound, a complexing agent, an aldehyde compound, and an amine compound represented by R-NH-CH-NH-Ror (CH-NH-CH-NH-CH)-R(wherein Rto Rrepresent -OH, -CH, -CHOH, -CHOH, -CHN(CH), -CHNH(CHOH), -CHNH(CHOH), -CHNH(CHOH), -CHNH(CHOH), -CHN(CHOH), -CHN(CHOH), -CHN(CHOH)or -CHN(CHOH), and n is an integer of 1 to 4). The electroless gold plating can be carried out without corrosion of an underlying metal to be plated at a stable deposition rate. Because of the high deposition rate and the immersion and reduction types, thickening of a plated coating is possible in one solution and the color of the coating is not degraded to provide a good appearance while keeping a lemon yellow color inherent to gold.