Process for producing polyester film

Abstract

The invention provides a method for producing a polyester film, the method sequentially carries out (a) the process of immersing the glass fiber matrix material in a solvent; (b) the process of immersing the glass fiber matrix material impregnated with the solvent in an epoxy resin; (c) the process of heating the glass fiber matrix material impregnated with epoxy resin; (d) the process of further impregnating the glass fiber matrix material impregnated and cured with epoxy resin in epoxy resin; (e) heating the impregnated The glass fiber matrix material process of epoxy resin, the reaction rate of the inner layer epoxy resin is more than 85%, and the reaction rate of the outer layer epoxy resin is less than 60%. As a result, the laminated board or multilayer circuit board after molding has excellent board thickness accuracy, and a prepreg film excellent in formability can be stably and reliably produced.

Description

technical field

[0001] The present invention relates to a method for producing a high-quality prepreg with high plate thickness accuracy, excellent formability, and less shedding of resin powder. The prepreg obtained by the present invention can be suitably used, for example, as a substrate of a cellular phone, a personal computer, an operating bus memory, a PDA, etc., which require high-frequency characteristics. Background technique

[0002] In recent years, laminated boards for circuit boards and multilayer circuit boards have used higher frequencies than before, and the requirements for the physical properties of their materials have become stricter. In particular, research has been conducted on circuit board materials for signal delay in circuits, and resins with controlled impedance have been developed by lowering the dielectric constant of circuit boards and improving the accuracy of board thickness after board molding. Since the plate thickness accuracy of the subst...

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