Circuit board and method for producing same

• US 4,313,995 A
• Filed: 04/20/1977
• Issued: 02/02/1982
• Est. Priority Date: 11/08/1976
• Status: Expired due to Term

• Current Assignee: Fortin Laminating Corporation
• Original Assignee: Fortin Laminating Corporation
• Inventors: Delgadillo, Joseph A.
• Primary Examiner(s): Lesmes, George F.
• Assistant Examiner(s): Buffalow, E. Rollins
• Application Number:
  US05/789,194
• Time in Patent Office: 1,749 Days
• Field of Search: 427/96, 427/292, 427/275, 427/259, 427/264, 156/253, 156/261, 156/516, 156/289, 156/153, 428/195, 428/901, 428/304, 428/209
• US Class Current: 428/201
• CPC Class Codes: H05K 2201/0129 Thermoplastic polymer, e.g. auto-adhesive layer; Shaping of thermoplastic polymer
• CPC Class Codes: H05K 2203/0108 Male die used for patterning, punching or transferring
• CPC Class Codes: H05K 2203/025 Abrading, e.g. grinding or sand blasting deburring, rounding, bevelling or smoothing conductor edges H05K2203/0346
• CPC Class Codes: H05K 2203/0522 Using an adhesive pattern
• CPC Class Codes: H05K 2203/0528 Patterning during transfer, i.e. without preformed pattern, e.g. by using a die, a programmed tool or a laser
• CPC Class Codes: H05K 3/041 by using a die for cutting the conductive material
• CPC Class Codes: H05K 3/046 by selective transfer or selective detachment of a conductive layer
• CPC Class Codes: H05K 3/382 by special treatment of the metal
• CPC Class Codes: Y10S 428/901 Printed circuit
• CPC Class Codes: Y10T 156/1057 Subsequent to assembly of laminae
• CPC Class Codes: Y10T 156/107 Punching and bonding pressure application by punch
• CPC Class Codes: Y10T 428/24802 Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.]
• CPC Class Codes: Y10T 428/24851 Intermediate layer is discontinuous or differential
• CPC Class Codes: Y10T 428/24917 including metal layer
• CPC Class Codes: Y10T 428/249994 Composite having a component wherein a constituent is liquid or is contained within preformed walls [e.g., impregnant-filled, previously void containing component, etc.]

Abstract

There is disclosed a method for producing an electrical circuit board comprising the steps of selectively treating a portion of a conductive metal sheet in a pattern substantially corresponding to a predetermined printed circuit configuration and in a manner which renders the pattern portion of the sheet essentially adherent to a resin, placing the treated pattern portion of the sheet in direct contact with a layer of resin on the surface of an insulating substrate to form an assembly, uniformly heating the assembly to an elevated temperature to selectively bond the substrate to the treated pattern portion of the sheet, cutting the sheet along the perimeter of the pattern portions and stripping the non-pattern portions of the sheet from the substrate to form a circuit board.

Claims

1. A circuit board assembly comprising;

a sheet of electrically conductive metal having a portion of the surface thereof containing a selectively roughened pattern in the configuration of a pre-determined electrically conductive circuit, said selectively roughened pattern being honed such that no metal is added to and substantially no metal is taken away from said surface of said sheet; and

a resin coated substrate bonded to said sheet of electrically conductive metal by the application of heat and pressure to the assembly, said resin coated substrate being essentially directly adherent to the roughened patterned portion of the surface of said sheet of electrically conductive metal and substantially nonadherent to the non-roughened portion of the surface of said sheet of electrically conductive metal whereby the non-roughened portion of the surface of said sheet of electrically conductive metal may be cut and removed from said resin coated substrate.

2. A circuit board assembly according to claim 1 further including a layer of release agent comprising a liquid wax selectively applied to the non-pattern areas whereby the substrate substantially will not adhere to the non-pattern areas.

3. A Circuit Board Assembly according to claim 1 further including a layer of release agent comprising a fluorocarbon resin selectively applied to the non-pattern areas whereby the substrate substantially will not adhere to the non-pattern areas.

4. An article according to claim 1 in which the metal is copper and the substrate is a thermoset epoxy-impregnated fiberglass fabric material.