Fibrillated liquid crystal polymer powder, method of producing fibrillated liquid crystal polymer powder, paste, resin multilayer substrate, and method of producing resin multilayer substrate

Abstract

A fibrillated liquid crystal polymer powder containing fibrillated liquid crystal polymer particles. A paste containing a dispersion medium and the fibrillated liquid crystal polymer powder. A method of producing the fibrillated liquid crystal polymer powder. A resin multilayer substrate obtained by laminating a plurality of resin sheets including at least one layer of a liquid crystal polymer sheet. On a surface of at least one layer of the liquid crystal polymer sheet, a thickness adjustment layer made of a fibrillated liquid crystal polymer powder containing fibrillated liquid crystal polymer particles is provided in a region insufficient in thickness when at least the plurality of resin sheets are laminated.

1 . A fibrillated liquid crystal polymer powder containing fibrillated liquid crystal polymer particles. 
     
     
         2 . A method of producing the fibrillated liquid crystal polymer powder according to  claim 1 , comprising, in the following order:
 a grinding step of grinding a biaxially-oriented liquid crystal polymer film to obtain said liquid crystal polymer powder; and   a fibrillating step of crushing the liquid crystal polymer powder by a wet high-pressure crushing device to obtain said fibrillated liquid crystal polymer powder.   
     
     
         3 . The method of producing the fibrillated liquid crystal polymer powder according to  claim 2 , wherein grinding using a freeze grinding method is performed in said grinding step. 
     
     
         4 . A paste containing a dispersion medium and the fibrillated liquid crystal polymer powder as defined in  claim 1  dispersed in the dispersion medium, and substantially not containing a binder resin component. 
     
     
         5 . The paste according to  claim 4 , wherein said dispersion medium is a liquid that can be dried within a temperature range less than or equal to a melting point of said liquid crystal polymer particles. 
     
     
         6 . The paste according to  claim 4 , further containing a liquid crystal polymer powder other than said fibrillated liquid crystal polymer powder. 
     
     
         7 . A resin multilayer substrate obtained by laminating a plurality of resin sheets and then integrating them by thermocompression bonding,
 said plurality of resin sheets including at least one layer of a liquid crystal polymer sheet made of a liquid crystal polymer as a principal material,   a conductive pattern being provided on a principal surface of at least one layer of said resin sheets,   on a surface of at least one layer of said liquid crystal polymer sheet, a thickness adjustment layer made of a fibrillated liquid crystal polymer powder containing fibrillated liquid crystal polymer particles as a principal material being provided in a region insufficient in thickness when at least said plurality of resin sheets are laminated.   
     
     
         8 . The resin multilayer substrate according to  claim 7 , wherein said fibrillated liquid crystal polymer powder is made of a liquid crystal polymer material that is the same as the liquid crystal polymer material of said liquid crystal polymer sheet. 
     
     
         9 . A method of producing a resin multilayer substrate obtained by laminating a plurality of resin sheets,
 said plurality of resin sheets including at least one layer of a liquid crystal polymer sheet made of a liquid crystal polymer as a principal material, the method comprising, in the following order:   a paste applying step of, on a surface of at least one layer of said liquid crystal polymer sheet, applying a paste containing a dispersion medium and a fibrillated liquid crystal polymer powder including liquid crystal polymer particles dispersed in the dispersion medium, and substantially not containing a binder resin component, to part of a region insufficient in thickness in a state where at least said plurality of resin sheets are laminated;   a laminating step of laminating said plurality of resin sheets to obtain a laminate; and   a thermocompression bonding step of applying pressure and heat to said laminate to bond said laminate by thermocompression to obtain a laminate including a thickness adjustment layer made of said paste.   
     
     
         10 . The paste according to  claim 5 , further containing a liquid crystal polymer powder other than said fibrillated liquid crystal polymer powder.