Extruded core laminates for circuit boards

Abstract

A method for fabrication of a circuit board laminate (10) in a continuous process employs an extruded laminate core (12). Streams of a fibrous material, microspheres or fused silica, a catalyst and a thermosetting resin are added to an extruder and the core extruded as a film; outer layers (18, 19) can be applied to the extruded core.

Description

[0001] This application claims priority from Provisional Patent Application 60 / 045387, filed May 2,1997. Background of the invention [0002] Circuit boards for current circulation generally comprise a multilayer composite material consisting of laminates comprising a thermosetting polymer and a suitable reinforcing substance. Typically, the reinforcing substance is a woven glass material, such as glass fibres. Thermosetting polymers are epoxy resins. A limitation that must be considered when producing multilayer composites is the reduced dimensional stability of the laminate, especially in response to temperature. Thermal cycling during circuit board operation can cause expansion and contraction of the laminate, resulting in loss of the required bond or corresponding connection between inner layers. Since the effective function of an electronic device depends on the correct positioning of these interconnection layers, incorrect positioning of the interconnection layers can ...

AI Technical Summary

Problems solved by technology

Although the dimensional stability of this laminate is improved, the high cost of producing this laminate reduces its viability

The use of organic solvents in the manufacture of laminates in this patent and the use of other laminates pose safety and environmental concerns

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