Method for producing a multilayer printed-circuit board

Claim 1

A method for producing a multilayer printed-circuit board using an electrically conductive copper paste including 70-85% by weight of copper powder, 15-30% by weight of at least one resin selected from the group of phenol resin, epoxy resin, polyestel resin and xylene resin, and a specific additive selected from anthracene and the derivative thereof, the method comprising the steps of: Printing the electrically conductive copper paste in a desired circuit pattern on at least one side of each of a predetermined number of electrically insulated prepreg base plates of epoxy resin; drying the base plates by heating the base plates at approximately 80° C. for approximately 30 minutes to harden the base plates and the copper paste; laminating the base plates by pressing the base plates together and heating the base plates at approximately 170° C. for approximately 30-60 minutes to additionally harden and fixedly attach the base plates to each other and thereby form a single multilayer printed-circuit board; and electrically connecting the multilayer printed circuits of the multilayer printed-circuit board.

Claim 2

A method for producing a multilayer printed-circuit board using an electrically conductive copper paste including 70-85% by weight of copper powder, 15-30% by weight of at least one resin selected from the group of phenol resin, epoxy resin, polyestel resin and xylene resin, and a specific additive selected from anthracene and the derivative thereof, the method comprising the steps of: Printing the electrically conductive copper paste in a desired circuit pattern on at least one side of each of a predetermined number of electrically insulated prepreg base plates of epoxy resin; drying the base plates by heating the base plates at approximately 80° C. for approximately 30 minutes to harden the base plates and the copper paste; laminating the base plates by pressing the base plates together and heating the base plates at approximately 170° C. for approximately 30-60 minutes to additionally harden and fixedly attach the base plates to each other and thereby form a single multilayer printed-circuit board; and electrically connecting the multilayer printed circuits of the multilayer printed-circuit board.

Claim 3

A method for producing a multilayer printed-circuit board using an electrically conductive copper paste including 70-85% by weight of copper powder, 15-30% by weight of at least one resin selected from the group of phenol resin, epoxy resin, polyestel resin and xylene resin, and a specific additive selected from anthracene and the derivative thereof, the method comprising the steps of: printing the electrically conductive copper paste in a desired circuit pattern on at least one side of each of a predetermined number of electrically insulated prepreg base plates of epoxy resin; drying the base plates at a first predetermined temperature for a first predetermined period of time to harden the base plates; laminating the base plates and pressing the base plates at a second predetermined temperature a second predetermined period of time to additionally harden and laminate the base plates into a single multilayer printed-circuit board; forming holes to extend through the single multilayer printed-circuit board in the direction of the thickness from the top to the bottom thereof; masking all surfaces of the board with a resist except for the surfaces of the holes through the board; processing the inner surfaces of the holes with an electrically conductive element to electrically connect the multilayer printed circuits of the board; removing the resist from the single multilayer printed-circuit board; and coating all surfaces of the single multilayer printed-circuit board with a flux; said first predetermined temperature being approximately 80° C., said second predetermined temperature being approximately 170° C., said first predetermined period of time being approximately 30 minutes and said second predetermined period of time being approximately 30-60 minutes.

Claim 4

A method for producing a multilayer printed-circuit board using an electrically conductive copper paste including 70-85% by weight of copper powder, 15-30% by weight of at least one resin selected from the group of phenol resin, epoxy resin, polyestel resin and xylene resin, and a specific additive selected from anthracene and the derivative thereof, the method comprising the steps of: printing the electrically conductive copper paste in a desired circuit pattern on at least one side of each of a predetermined number of electrically insulated prepreg base plates of epoxy resin; drying the base plates at a first predetermined temperature for a first predetermined period of time to harden the base plates; laminating the base plates and pressing the base plates at a second predetermined temperature a second predetermined period of time to additionally harden and laminate the base plates into a single multilayer printed-circuit board; forming holes to extend through the single multilayer printed-circuit board in the direction of the thickness from the top to the bottom thereof; masking all surfaces of the board with a resist except for the surfaces of the holes through the board; processing the inner surfaces of the holes with an electrically conductive element to electrically connect the multilayer printed circuits of the board; removing the resist from the single multilayer printed-circuit board; and coating all surfaces of the single multilayer printed-circuit board with a flux; said first predetermined temperature being approximately 80° C., said second predetermined temperature being approximately 170° C., said first predetermined period of time being approximately 30 minutes and said second predetermined period of time being approximately 30-60 minutes.