Heat-dissipating sheet having high thermal conductivity and its production method

摘要

A heat-dissipating sheet having a density of 2.0 g/cm3 or more and an in-plane thermal conductivity of 580 W/mK or more, which comprises carbon black uniformly dispersed among fine graphite particles, a mass ratio of fine graphite particles to carbon black being 75/25 to 95/5, and the carbon black being composed of channel black and ketjen black and/or acetylene black is produced by applying a dispersion of fine graphite particles, carbon black and an organic binder in an organic solvent to a surface of a die, drying it; burning the resultant resin-containing composite sheet to remove the organic binder; and then pressing the resultant composite sheet of fine graphite particles and carbon black for densification.

主权项

1. A heat-dissipating sheet consisting essentially of fine graphite particles and carbon black uniformly dispersed among fine graphite particles;
a mass ratio of fine graphite particles to carbon black being 75/25 to 95/5; said carbon black being composed of channel black and at least one of ketjen black and acetylene black: a mass ratio of channel black to at least one of ketjen black and acetylene black being 4/1-1/3: said fine graphite particles having an average diameter of 3-150 μm and average thickness of 200 nm or more; said carbon black having an average primary particle size of 20-200 nm; whereby said heat-dissipating sheet has a density of 2.0 g/cm3 or more and an inplane thermal conductivity of 580 W/mK or more.