Abstract: Copper or copper alloy sheet or foil displaying excellent solderability and high resistance to tarnish is prepared by the provision over its surface of a coating containing a copper salt of an organophosphonic acid. To form the coating, the sheet or foil is immersed for a short time in an aqueous solution containing a phosphonic acid, rinsed and dried, the treatment being combined with or preceded by oxidation of the sheet surface.

Abstract: Copper or copper alloy sheet or foil displaying improved forming and working properties is prepared by the provision over its surface of a thin coating containing a copper salt of an organophosphonic acid, and subsequently, an outer film of lubricant strongly retained by the coating is applied. To form the coating, the sheet or foil is immersed for a short time in an aqueous solution containing a phosphonic acid, rinsed and dried, the treatment being combined with or preceded by oxidation of the sheet surface, and the lubricant film is applied prior to forming operations, preferably as the final step in the production of the cupreous sheet.

Abstract: Copper or copper alloy sheet or foil displaying excellent solderability and high resistance to tarnish is prepared by the provision over its surface of a coating containing a copper salt of an organophosphonic acid. To form the coating, the sheet or foil is immersed for a short time in an aqueous solution containing a phosphonic acid, rinsed and dried, the treatment being combined with or preceded by oxidation of the sheet surface.

Abstract: A method of producing a laminate having high bond strength and excellent resistance to acid undercutting comprising oxidizing copper or its alloys to form an oxide film, applying a phosphoric acid solution to the oxide film, rinsing, drying, and adhesively laminating to a plastic film. The instant case also teaches a method of producing high tarnish resistance on copper and its alloys by so oxidizing and phosphating and further teaches a flexible printed circuit wherein the unwanted copper portion of the formed laminate is etched away, characterized by high peel strength and substantially no acid undercutting of the formed circuitry.

Abstract: The instant invention comprises providing copper or a copper alloy which has on its surface a uniform glassy like and substantially pore free coating of copper phosphate, rinsing the coated material for at least 2 seconds in water at a pH of from 4.9 to 6.3, at a temperature of 90.degree.C to the boiling point and drying.

Abstract: The instant invention comprises providing copper or a copper alloy which has on its surface a uniform glassy like and substantially pore free coating of copper phosphate, rinsing the coated material for at least two seconds in water at a pH of from 4.9 to 6.3, at a temperature of 90.degree.C to the boiling point and drying.

Abstract: The instant invention comprises providing copper or a copper alloy which has on its surface a uniform glassy like and substantially pore free coating of copper phosphate, rinsing the coated material for at least two seconds in water at a pH of at least 8.0, at a temperature of 90.degree.C to the boiling point and drying.

Abstract: The instant invention comprises providing copper or a copper alloy which has on its surface a uniform glassy like and substantially pore free coating of copper phosphate, rinsing the coated material for at least two seconds in water at a pH of at least 8.0, at a temperature of 90.degree.C to the boiling point and drying.