abstract |
A METHOD OF PRODUCING A LAMINATE HAVING HIGH BOND STRENGTH AND EXCELLENT RESISTANCE TO ACID UNDERCUTTING COMPRISING APPLYING A PHOSPHORIC ACID SOLUTION CONTAINING A DICHROMATE TO COPPER OR ITS ALLOY, RISING, DRYING, AND ADHESIVELY LAMINATING TO A PLASTIC FILM, THE INSTANT CASE ALSO TEACHES A METHOD OF PRODUCING A HIGH TARNISH RESISTANT COPPER AND COPPER ALLOY BY SO TREATING, AS WELL AS A FLEXIBLE PRINTED CIRCUIT CHARACTERIZED BY HIGH BOND STRENGTH AND THE ABSENCE OF ACID UNDERCUTTING. |