Metal-coated polyimide

An electroless deposition-catalyzing film-forming solution comprising:

• (A) 0.1 to 15 weight percent of a polyamic acid of the structural formula ##STR4## where n is greater than 10;
• where R.sub.1 is a carbon-carbon bond, --C(O)--, a C.sub.1 -C.sub.12 alkyl group, a C.sub.1 -C.sub.12 alkylene group, a polyakylene oxide, or ##STR5## where R.sub.2 is a carbon-carbon bond, --C(O)--, --SO.sub.2 --, --CH.sub.2 --, --CH(CH.sub.3)--, --C(CH.sub.3).sub.2 --, --C(CF.sub.3).sub.2 --, or --O--;
• where R.sub.3 is a C.sub.1 -C.sub.12 alkyl group, a C.sub.1 -C.sub.12 alkylene group, a polyakylene oxide, --phenyl--, --phenyl--R.sub.4 --phenyl-- or --phenyl--O--phenyl--R.sub.4 --phenyl--O--phenyl--;
• and where R.sub.4 is a carbon-carbon bond, --C(O)--, --SO.sub.2 --, --CH.sub.2 --, --CH (CH.sub.3)--, --C(CH.sub.3).sub.2 --, --C(CF.sub.3)-- or --O--;
• (B) 0.1 to 15 parts per hundred parts of polyamic acid of a noble metal selected from the group consisting of palladium, platinum, rhodium, iridium, ruthenium, silver and gold;
• (C) 60 to 95 weight percent of an aprotic solvent selected from the group consisting of acetone, dimethylacetamide, dimethylformamide, dimethylsulfoxide, ethylene dichloride, methyl ethyl ketone, methyl isobutyl ketone, tetrahydrofuran, N-methyl-2-pyrrolidone, toluene, xylene, mixtures thereof and mixtures thereof with water;
• and
• (D) 0 to 10 weight percent of an anionic or non-ionic surfactant.