Claims
- 1. A method of forming a printed circuit device comprising a rigid perforate substrate having an insulating surface bonded to one face of a two-faced flexible insulating sheet having thin conductive patterns produced on each of said faces, said flexible sheet having conductive through holes electrically connecting portions of the pattern on one face to portions of the pattern on the opposite face, which comprises the steps of:
- (a) depositing a layer of a tacky contact adhesive comprising a rubber modified epoxy resin containing dispersed polyester fibers upon the rigid perforate substrate member,
- (b) aligning said flexible insulating sheet upon the epoxy resin-coated surface of the substrate,
- (c) attaching the flexible insulating sheet to the epoxy resin-coated surface of the substrate by applying sufficient pressure thereto to establish a firm contact bond,
- (d) selectively removing adhesive in the through holes with a solvent selected from the group consisting of 1,1,1-trichloroethylene, trichloroethane and methylene chloride, thereby resulting in registration of through holes in the sheet with perforations in the rigid substrate, and
- (e) curing the adhesive to an insoluble state.
- 2. Method in accordance with claim 1 wherein curing is effected at a bond line temperature within the range of 320.degree.-345.degree. F. for a time period ranging from 35-45 minutes, the shorter time periods corresponding with the higher temperatures, and the converse.
Parent Case Info
This is a continuation of application Ser. No. 648,288 filed Jan. 12, 1976, now abandoned.
US Referenced Citations (3)
Continuations (1)
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Number |
Date |
Country |
Parent |
648288 |
Jan 1976 |
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