Flexible laminates and method of making the laminates

• US 6,015,607 A
• Filed: 04/14/1997
• Issued: 01/18/2000
• Est. Priority Date: 06/28/1995
• Status: Expired due to Fees

• Current Assignee: Fraivillig Materials Company
• Original Assignee: Fraivillig Materials Company
• Inventors: Fraivillig, James
• Primary Examiner(s): Nakarani, D. S.
• Assistant Examiner(s): TARAZANO, DONALD LAWRENCE
• Application Number:
  US08/834,105
• Time in Patent Office: 1,009 Days
• Field of Search: 428/473.5, 428/180, 428/475.2, 428/450, 428/447, 428/448, 428/458, 428/337, 428/336, 428/333, 428/209, 428/901, 428/457, 428/214, 428/216, 174/254
• US Class Current: 428/214
• CPC Class Codes: B32B 15/08 of synthetic resin
• CPC Class Codes: B32B 15/20 comprising aluminium or copper B32B15/016 and B32B15/017 take precedence
• CPC Class Codes: B32B 2311/12 Copper
• CPC Class Codes: B32B 2371/00 Polyethers, e.g. PEEK, i.e. polyether-etherketone; PEK, i.e. polyetherketone
• CPC Class Codes: B32B 2379/08 Polyimides
• CPC Class Codes: B32B 2457/08 PCBs, i.e. printed circuit boards
• CPC Class Codes: B32B 7/12 using interposed adhesives or interposed materials with bonding properties
• CPC Class Codes: H05K 1/0393 Flexible materials H05K1/038 takes precedence; specific organic compositions are classified in H05K1/0313 and subgroups
• CPC Class Codes: H05K 2201/0129 Thermoplastic polymer, e.g. auto-adhesive layer; Shaping of thermoplastic polymer
• CPC Class Codes: H05K 2201/0154 Polyimide
• CPC Class Codes: H05K 2201/0162 Silicon containing polymer, e.g. silicone
• CPC Class Codes: H05K 2201/0209 Inorganic, non-metallic particles
• CPC Class Codes: H05K 2201/0355 Metal foils
• CPC Class Codes: H05K 2203/1545 Continuous processing, i.e. involving rolls moving a band-like or solid carrier along a continuous production path
• CPC Class Codes: H05K 3/386 by the use of an organic polymeric bonding layer, e.g. adhesive
• CPC Class Codes: H05K 3/4626 characterised by the insulating layers or materials H05K3/4688 takes precedence
• CPC Class Codes: H05K 3/4635 laminating flexible circuit boards using additional insulating adhesive materials between the boards
• CPC Class Codes: Y10S 428/901 Printed circuit
• CPC Class Codes: Y10T 428/24959 of adhesive layers
• CPC Class Codes: Y10T 428/24975 No layer or component greater than 5 mils thick
• CPC Class Codes: Y10T 428/31616 : Next to polyester [e.g., alkyd]
• CPC Class Codes: Y10T 428/31681 : Next to polyester, polyamide or polyimide [e.g., alkyd, glue, or nylon, etc.]
• CPC Class Codes: Y10T 428/31721 : Of polyimide
• CPC Class Codes: Y10T 428/31786 : Of polyester [e.g., alkyd, etc.]

Abstract

A flexible laminate for use in flexible circuitry including at least one layer of a flexible film substrate; at least one layer of a metal foil on top of the flexible film substrate; and an adhesive including a polyetherimide, and preferably a siloxane polyetherimide copolymer, present between said flexible film substrate and said metal foil; in which the adhesive bonds the metal foil to the flexible film substrate.

Claims

1. A flexible circuit, comprising:

a flexible substrate comprising a polyimide, polyester or polyetherimide, the flexible substrate having a thickness selected to enable flexure consistent with use in the flexible circuit;

an adhesive layer on the flexible substrate, the adhesive layer consisting of siloxane polyetherimide copolymer as the only polymeric component; and

a metal foil layer on the adhesive layer.

2. The flexible circuit as defined in claim 1 wherein the flexible substrate comprises alumina-filled polyimide film.

3. The flexible circuit as defined in claim 1 wherein the flexible substrate has a thickness within a range of 0.5 to 5 mil and the adhesive layer has a thickness in a range of 0.15 to 0.30 mil.

4. The flexible circuit as defined in claim 1 wherein the metal foil layer comprises copper having a thickness in a range of 19-75 microns.

5. The flexible circuit as defined in claim 1 further comprising a cover layer on the metal foil layer.

6. The flexible circuit as defined in claim 5 wherein the cover layer comprises a polyetherimide copolymer resin.

7. The flexible circuit as defined in claim 1 wherein the flexible substrate comprises polyimide formed from a mixture of equimolar amounts of diamine and a dianhydride.