Manufacturing method of LCP film for circuit board and T-die melt extrusion LCP film for circuit board

摘要

LCP for circuit boards that can realize LCP films for circuit boards with low linear expansion coefficient and excellent dimensional stability without excessively impairing the excellent basic performance of liquid crystal polyester such as mechanical properties, electrical properties, and heat resistance. Provided is a method for producing a film and the like. A composition preparation step of preparing an LCP resin composition containing at least 100 parts by mass of liquid crystal polyester and 1 to 20 parts by mass of polyarylate, and a T-die melt extrusion of the LCP resin composition to obtain a linear expansion coefficient in the TD direction ( A film forming step of forming a T-die melt-extruded LCP film having an α2) of 50 ppm / K or more and a pressure-heat treatment of the T-die melt-extruded LCP film have a linear expansion coefficient (α2) of 16.8 in the TD direction. A method for producing an LCP film for a circuit board, which comprises at least a pressurizing and heating step for obtaining an LCP film for a circuit board of ± 12 ppm / K.