Aluminum electroplating method
AssigneesMitsubishi Petrochemical Co., Ltd., Nisshin Steel Co., Ltd.
InventorsShoichiro Mori, Kazuhiko Ida, Hitoshi Suzuki, Seteuko Takahashi, Isao Saeki
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Abstract
There is disclosed an aluminum electroplating method, which compriss using a low melting composition comprising a mixture of 20 to 80 mole % of an aluminum halide and 80 to 20 mole % of an onium halide of a nitrogen-containing compound selected from the group consisting of bicyclic quaternary amidinium halides, 1-alkylaminopyridinium halides, trialkylimidazolium halides, benzimidazolium halides, alicyclic quaternary ammonium halides and asymmetric tetraalkylammonium halides.
Claims11
An aluminum electroplating method, which comprises using a low melting composition comprising a mixture of 20 to 80 mole % of an aluminum halide and 80 to 20 mole % of an onium halide of a nitrogen-containing compound selected from the group consisting of those shown below as the plating bath:
- (i) bicyclic quaternary amidinium halides of the formula:
- ##STR7## wherein R.sup.1 is an alkyl group having 1 to 12 carbon atoms, R.sup.2, R.sup.3 each represent an alkylene group having 1 to 6 carbon atoms, the alkyl group or alkylene group mentioned here referring to straight hydrocarbon groups, branched hydrocarbon groups and further those containing aromatic hydrocarbon groups in a part thereof and X represents a halogen atom,
- (ii) 1-alkylaminopyridinium halides of the formula:
- ##STR8## wherein R.sup.4 is an alkyl group having 1 to 12 carbon atoms, R.sup.5 hydrogen atom or an alkyl group having 1 to 6 carbon atoms and R.sup.6 an alkyl group having 1 to 6 carbon atoms, the alkyl group mentioned here referring to straight hydrocarbon groups, branched hydrocarbon groups and further those containing aromatic hydrocarbon groups in a part thereof and X has the same meaning as defined above,
- (iii) trialkylimidazolium halides of the formula:
- ##STR9## .multidot.wherein R.sup.7, R.sup.8 and R.sup.9 each represent an alkyl group having 1 to 6 carbon atoms, the alkyl group mentioned here referring to straight hydrocarbon groups, branched hydrocarbon groups and further those containing aromatic hydrocarbon groups in a part thereof and X has the same meaning as defined above,
- (iv) benzimidazolium halides of the formula:
- ##STR10## wherein R.sup.10 and R.sup.11 each represent an alkyl group having 1 to 6 carbon atoms and X has the same meaning as defined above,
- (v) alicyclic quaternary ammonium halides of the formula:
- ##STR11## wherein R.sup.12 represents an alkylene group having 1 to 6 carbon atoms, R.sup.13 and R.sup.14 each represent an alkyl group having 1 to 6 carbon atoms and X has the same meaning as defined above, and
- (vi) asymmetric tetraalkylammoium halides of the formula:
- ##STR12## wherein R.sup.15, R.sup.16, R.sup.17 and R.sup.18 are each an alkyl group having 1 to 12 carbon atoms, provided that at least one is different from other alkyl groups and X has the same meaning as defined above.
Dependencies are inferred from the claim text.