Filler-Filled Highly Thermally Conductive Dispersion Composition Having Excellent Segregation Stability, Method for Producing Said Dispersion Composition, Filler-Filled Highly Thermally Conductive Material Using Said Dispersion Composition, Method for Producing Said Material, and Molded Article Obtained using Said Material

Abstract

A filler-loaded thermal conductive liquid compositions formed by dispersing a powder composition, which contains polymer particles containing thermoplastic polymer particles, and thermal conductive filler particles containing particles having a graphite-like structure, obtained by pulverizing 5-70 parts by weight of the polymer particles and 30-95 parts by weight of the thermal conductive filler particles, the filler particles being covered with micronized polymer particles and the covered particles being uniformly dispersed, using 25-250 parts by weight of a liquid reactive dispersing medium and/or a dispersing medium containing a thermoplastic polymer having a deflection temperature under load or a melting point lower than the thermoplastic polymer used in the powder composition, and the liquid composition having conditions that a thermal conductive infinite cluster exhibiting a thermal conductivity of 1-35 w/mk is formed and a concentration of thermal conductive filler particles is equal to or more than a percolation threshold.

1 - 28 . (canceled) 
     
     
         29 . A filler-loaded high thermal conductive dispersion liquid composition being formed by uniformly dispersing a powder composition, which contains organic polymer particles containing thermoplastic polymer particles, and high thermal conductive filler particles which contain filler particles having a graphite-like structure and is obtained by pulverizing 5 to 70 parts by weight of the organic polymer particles and 30 to 95 parts by weight of the high thermal conductive filler particles with respect to 100 parts by weight of the total amount of these components by using a pulverizing machine, which performs grinding with frictional force or impact force, to cause delamination or cohesive failure while maintaining an average planar particle size of the filler particles having a graphite-like structure, in the powder composition, the vicinity of the high thermal conductive filler particles being covered with the micronized organic polymer particles and the covered particles being uniformly dispersed, using 25 to 250 parts by weight of a liquid reactive dispersing medium and/or a dispersing medium containing a thermoplastic polymer having a deflection temperature under load or a melting point lower than that of the thermoplastic polymer used in the powder composition by 5 to 150° C. with respect to 100 parts by weight of the powder composition, and
 the dispersion liquid composition having conditions that a thermal conductive infinite cluster exhibiting a thermal conductivity of 1 to 35 W/mK is formed and a concentration of the high thermal conductive filler particles is equal to or more than a percolation threshold. 
 
     
     
         30 . The filler-loaded high thermal conductive dispersion liquid composition according to  claim 29 , wherein the dispersing medium comprises the liquid reactive dispersing medium. 
     
     
         31 . The filler-loaded high thermal conductive dispersion liquid composition according to  claim 29 , wherein the dispersing medium does not comprise the liquid reactive dispersing medium. 
     
     
         32 . The filler-loaded high thermal conductive dispersion liquid composition according to  claim 29 , wherein the dispersing medium does not comprise the thermoplastic polymer having a deflection temperature under load or a melting point lower than that of the thermoplastic polymer used in the powder composition by 5 to 150° C. 
     
     
         33 . The filler-loaded high thermal conductive dispersion liquid composition according to  claim 29 , wherein the pulverizing machine is a ball mill, a roller mill, a bead mill, or a medium mill. 
     
     
         34 . The filler-loaded high thermal conductive dispersion liquid composition according to  claim 29 , wherein the thermoplastic polymer particles used in the powder composition contain at least one selected from the group consisting of a thermoplastic resin and a thermoplastic elastomer, all of which have crystallinity and/or aromaticity. 
     
     
         35 . The filler-loaded high thermal conductive dispersion liquid composition according to  claim 29 , wherein the thermoplastic polymer particles used in the powder composition contain at least one selected from the group consisting of polyphenylene sulfide, polyethylene terephthalate, polybutylene terephthalate, polycarbonate, polyamide, polyethylene, and polypropylene. 
     
     
         36 . The filler-loaded high thermal conductive dispersion liquid composition according to  claim 29 , wherein the filler particles having a graphite-like structure are hexagonal boron nitride particles and a thermal conductivity thereof is 1 to 25 W/mK. 
     
     
         37 . The filler-loaded high thermal conductive dispersion liquid composition according to  claim 36 , wherein the high thermal conductive filler particles further contain magnesium oxide particles. 
     
     
         38 . The filler-loaded high thermal conductive dispersion liquid composition according to  claim 29 , wherein the high thermal conductive filler particles contain graphite particles and a thermal conductivity thereof is 3 to 35 W/mK. 
     
     
         39 . The filler-loaded high thermal conductive dispersion liquid composition according to  claim 38 , wherein the graphite particles contain natural graphite particles and/or artificial graphite particles. 
     
     
         40 . The filler-loaded high thermal conductive dispersion liquid composition according to  claim 39 , wherein the natural graphite particles contain scale-like graphite particles. 
     
     
         41 . The filler-loaded high thermal conductive dispersion liquid composition according to  claim 29 , wherein the liquid dispersing medium contains the reactive dispersing medium and the reactive dispersing medium contains an uncured thermosetting resin. 
     
     
         42 . The filler-loaded high thermal conductive dispersion liquid composition according to  claim 41 , wherein the uncured thermosetting resin contains a benzoxazine resin and/or a phenol-based epoxy resin. 
     
     
         43 . The filler-loaded high thermal conductive dispersion liquid composition according to  claim 41 , wherein the uncured thermosetting resin contains an epoxy reactive diluent and/or an epoxy-modified silicone resin. 
     
     
         44 . The filler-loaded high thermal conductive dispersion liquid composition according to  claim 41 , wherein the liquid reactive dispersing medium contains a curing agent. 
     
     
         45 . The filler-loaded high thermal conductive dispersion liquid composition according to  claim 44 , wherein the curing agent contains at least one resin selected from the group consisting of an amine-modified silicone resin, an alcohol-modified silicone resin, and a carboxylic acid-modified silicone resin. 
     
     
         46 . The filler-loaded high thermal conductive dispersion liquid composition according to  claim 41 , wherein the liquid reactive dispersing medium contains a catalyst. 
     
     
         47 . The filler-loaded high thermal conductive dispersion liquid composition according to  claim 43 , wherein the catalyst contains an imidazole compound. 
     
     
         48 . The filler-loaded high thermal conductive dispersion liquid composition according to  claim 29 , wherein the dispersing medium contains the thermoplastic polymer and a deflection temperature under load or a melting point of the thermoplastic polymer is lower than that of the thermoplastic polymer particles used in the powder composition by 10 to 100° C. 
     
     
         49 . The filler-loaded high thermal conductive dispersion liquid composition according to  claim 29 , wherein a viscosity at a temperature at the time of cast molding or potting is 100 mPa·s or more and 300 Pa·s or less. 
     
     
         50 . The filler-loaded high thermal conductive dispersion liquid composition according to  claim 29 , wherein the thermal conductive infinite cluster is based on a high thermal conductive filler-rich phase mainly attributable to the powder composition. 
     
     
         51 . A method for producing a filler-loaded high thermal conductive dispersion liquid composition, the method comprising:
 a step (1) of obtaining a powder composition, which contains organic polymer particles containing thermoplastic polymer particles, and high thermal conductive filler particles which contain filler particles having a graphite-like structure, by pulverizing 5 to 70 parts by weight of the organic polymer particles and 30 to 95 parts by weight of the high thermal conductive filler particles with respect to 100 parts by weight of the total amount of these components by using a pulverizing machine, which performs grinding with frictional force or impact force, to cause delamination or cohesive failure while maintaining an average planar particle size of the filler particles having a graphite-like structure, in the powder composition, the vicinity of the high thermal conductive filler particles being covered with the micronized organic polymer particles and the covered particles being uniformly dispersed; and   a step (2) of uniformly dispersing the powder composition using 25 to 250 parts by weight of a liquid reactive dispersing medium and/or a dispersing medium containing a thermoplastic polymer having a deflection temperature under load or a melting point lower than that of the thermoplastic polymer particles used in the powder composition by 5 to 150° C. with respect to 100 parts by weight of the powder composition to prepare a dispersion liquid composition having conditions that a thermal conductive infinite cluster exhibiting a thermal conductivity of 1 to 35 W/mK is formed and a concentration of the high thermal conductive filler is equal to or more than a percolation threshold.   
     
     
         52 . A filler-loaded high thermal conductive material being formed by uniformly dispersing a powder composition, which contains organic polymer particles containing thermoplastic polymer particles, and high thermal conductive filler particles which contain filler particles having a graphite-like structure and is obtained by pulverizing 5 to 70 parts by weight of the organic polymer particles and 30 to 95 parts by weight of the high thermal conductive filler particles with respect to 100 parts by weight of the total amount of these components by using a pulverizing machine, which performs grinding with frictional force or impact force, to cause delamination or cohesive failure while maintaining an average planar particle size of the filler particles having a graphite-like structure, in the powder composition, the vicinity of the high thermal conductive filler particles being covered with the micronized organic polymer particles and the covered particles being uniformly dispersed, using 25 to 400 parts by weight of a liquid reactive dispersing medium and/or a dispersing medium containing a thermoplastic polymer having a deflection temperature under load or a melting point lower than that of the thermoplastic polymer used in the powder composition by 5 to 150° C. with respect to 100 parts by weight of the powder composition, and by causing a dispersion liquid composition having conditions that a thermal conductive infinite cluster exhibiting a thermal conductivity of 1 to 35 W/mK is formed and a concentration of the high thermal conductive filler is equal to or more than a percolation threshold to react under a condition that the liquid reactive dispersing medium forms a crosslinked polymer when the dispersing medium comprises the liquid reactive dispersing medium, or to be fluidized at a temperature that is equal to or lower than a deflection temperature under load or a melting point of the thermoplastic polymer particles used in the powder composition and is equal to or higher than a deflection temperature under load or a melting point of the thermoplastic polymer used in the dispersing medium when the dispersing medium comprises the thermoplastic resin, then to be molded by heating at a pressure of 0 to 1000 kgf/cm 2  and at a temperature equal to or higher than a deflection temperature under load or a melting point of the thermoplastic polymer particles used in the powder composition, and cooled and solidified, wherein the filler-loaded high thermal conductive material contains a high thermal conductive filler-rich phase and a high thermal conductive filler-non-rich phase and the high thermal conductive filler-rich phase forms a thermal conductive infinite cluster. 
     
     
         53 . The filler-loaded high thermal conductive material according to  claim 52 , wherein the high thermal conductive filler rich phase consists of the high thermal conductive filler and the reactive dispersing medium when the dispersing medium contains the liquid reactive dispersing medium. 
     
     
         54 . The filler-loaded high thermal conductive material according to  claim 52 , wherein the high thermal conductive filler-rich phase consists of the high thermal conductive filler and either of the thermoplastic polymer used in the powder composition or the thermoplastic powder having a deflection temperature under load or a melting point lower than that of the thermoplastic polymer used in the powder composition. 
     
     
         55 . A method for producing a filler-loaded high thermal conductive material, the method comprising:
 a step (1) of obtaining a powder composition, which contains organic polymer particles containing thermoplastic polymer particles, and high thermal conductive filler particles which contain filler particles having a graphite-like structure, by pulverizing 5 to 70 parts by weight of the organic polymer particles and 30 to 95 parts by weight of the high thermal conductive filler particles with respect to 100 parts by weight of the total amount of these components by using a pulverizing machine, which performs grinding with frictional force or impact force, to cause delamination or cohesive failure while maintaining an average planar particle size of the filler particles having a graphite-like structure, in the powder composition, the vicinity of the high thermal conductive filler particles being covered with the micronized organic polymer particles and the covered particles being uniformly dispersed;   a step (2) of uniformly dispersing the powder composition using 25 to 250 parts by weight of a liquid reactive dispersing medium and/or a dispersing medium containing a thermoplastic polymer having a deflection temperature under load or a melting point lower than that of the thermoplastic polymer particles used in the powder composition by 5 to 150° C. with respect to 100 parts by weight of the powder composition to prepare a dispersion liquid composition having conditions that a thermal conductive infinite cluster exhibiting a thermal conductivity of 1 to 35 W/mK is formed and a concentration of the high thermal conductive filler particles is equal to or more than a percolation threshold;   a crosslinking step (3) of allowing the dispersion liquid composition to react under a condition that the liquid reactive dispersing medium forms a crosslinked polymer when the dispersing medium comprises the liquid reactive dispersing medium;   a fluidizing step (4) of fluidizing the thermoplastic polymer used in the dispersing medium at a temperature that is equal to or lower than a deflection temperature under load or a melting point of the thermoplastic polymer used in the powder composition and is equal to or higher than a deflection temperature under load or a melting point of the thermoplastic polymer used in the dispersing medium when the dispersing medium comprises the thermoplastic resin;   a step (5) of molding by heating the material formed in the crosslinking step (3) and/or the fluidizing step (4) at a pressure of 0 to 1000 kgf/cm 2  and at a temperature equal to or higher than a deflection temperature under load or a melting point of the thermoplastic polymer particles used in the powder composition; and   a step (6) of cooling and solidifying the material formed in the step (5).   
     
     
         56 . The method for producing a filler-loaded high thermal conductive material according to  claim 55 , wherein the condition that the liquid reactive dispersing medium forms a crosslinked polymer is that the reactive dispersing medium has a degree of cure of 80% or more. 
     
     
         57 . A molded article comprising the filler-loaded high thermal conductive material according to  claim 52 , the molded article being used as a high thermal conductive/heat dissipation component. 
     
     
         58 . A molded article comprising a filler-loaded high thermal conductive material produced by the production method according to  claim 55 , the molded article being used as a high thermal conductive/heat dissipation component. 
     
     
         59 . The molded article according to  claim 57 , wherein the molded article is formed by laminating two layers of the filler-loaded high thermal conductive material,
 one layer of the two layers has a thermal conductivity of 3 to 35 W/mK and exhibits electrical conductivity with a surface electrical conductivity of 70 (Ωcm) −1  or less, and   the other layer of the two layers has a thermal conductivity of 1 to 25 W/mK and is a semiconductor having a surface electrical conductivity of 0.1 to 10 −10  (Ωcm) −1  or exhibits insulating properties with a surface electrical conductivity of 10 −10  (Ωcm) −1  or less.   
     
     
         60 . The molded article according to  claim 57 , wherein layers of the two layers of the filler-loaded high thermal conductive material are layers formed from gradient materials having different filler concentrations from each other. 
     
     
         61 . A method for producing a molded article being used as a high thermal conductive/heat dissipation component, comprising producing the molded article by using the filler-loaded high thermal conductive material according to  claim 52 . 
     
     
         62 . A method for producing a molded article being used as a high thermal conductive/heat dissipation component, comprising producing the molded article by using a filler-loaded high thermal conductive material produced by the production method according to  claim 55 .