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EP-4737519-A1 - HEAT DISSIPATION FILLER, RESIN COMPOSITION, AND RESIN MOLDED BODY

EP4737519A1EP 4737519 A1EP4737519 A1EP 4737519A1EP-4737519-A1

Abstract

The heat dissipating filler of the present invention is a heat dissipating filler used for manufacturing a resin molded body, the heat dissipating filler comprising: first heat conductive particles each having a particle size of 10 µm or more and 150 µm or less; second heat conductive particles each having a particle size of 0.1 µm or more and less than 10 µm; and aluminum nitrides formed into a fibrous shape, wherein, when a total amount of the first heat conductive particles, the second heat conductive particles and the aluminum nitrides formed into the fibrous shape is 100 parts by volume, the heat dissipating filler contains the first heat conductive particles in a ratio of 30 parts by volume or more and 80 parts by volume or less, the second heat conductive particles in a ratio of 5 parts by volume or more and 50 parts by volume or less and the aluminum nitrides formed into the fibrous shape in a ratio of 1 part by volume or more and 40 parts by volume or less.

Inventors

  • WATANABE, SHOTA

Assignees

  • U-MAP Co., Ltd.

Dates

Publication Date
20260506
Application Date
20240723

Claims (12)

  1. A heat dissipating filler used for manufacturing a resin molded body, the heat dissipating filler comprising: first heat conductive particles each having a particle size of 10 µm or more and 150 µm or less; second heat conductive particles each having a particle size of 0.1 µm or more and less than 10 µm; and aluminum nitrides formed into a fibrous shape, wherein, when a total amount of the first heat conductive particles, the second heat conductive particles and the aluminum nitrides formed into the fibrous shape is 100 parts by volume, the heat dissipating filler contains the first heat conductive particles in a ratio of 30 parts by volume or more and 80 parts by volume or less, the second heat conductive particles in a ratio of 5 parts by volume or more and 50 parts by volume or less and the aluminum nitrides formed into the fibrous shape in a ratio of 1 part by volume or more and 40 parts by volume or less.
  2. The heat dissipating filler as claimed in claim 1, wherein the first heat conductive particles contain at least one selected from the group consisting of aluminum nitride, boron nitride and alumina.
  3. The heat dissipating filler as claimed in claim 1, wherein the second heat conductive particles contain at least one selected from the group consisting of aluminum nitride, alumina and silica.
  4. The heat dissipating filler as claimed in claim 1, wherein a length in a long axis direction of the aluminum nitrides formed into the fibrous shape is 1.0 µm or more and 5.0 cm or less.
  5. The heat dissipating filler as claimed in claim 1, wherein a length in a short axis direction of the aluminum nitrides formed into the fibrous shape is 0.5 µm or more and 50.0 µm or less.
  6. The heat dissipating filler as claimed in claim 1, wherein an aspect ratio of the aluminum nitrides formed into the fibrous shape is 2 or more and 200 or less.
  7. A resin composition used for manufacturing a resin molded body made of a material containing a resin material, the resin composition comprising the heat dissipating filler as claimed in any one of claims 1 to 6.
  8. The resin composition as claimed in claim 7, wherein a content of the resin material in the resin composition is 5% by volume or more and 60% by volume or less.
  9. A resin molded body made of a material containing a resin material, the resin molded body comprising the heat dissipating filler as claimed in any one of claims 1 to 6.
  10. The resin molded body as claimed in claim 9, wherein a content of the resin material in the resin molded body is 5% by volume or more and 60% by volume or less.
  11. The resin molded body as claimed in claim 9, wherein heat conductivity of the resin molded body in each of three mutually perpendicular axial directions is 0.5 W/m·K or more and 20 W/m·K or less.
  12. The resin molded body as claimed in claim 9, wherein the resin molded body has a withstand voltage of 1 kV/mm or more and 100 kV/mm or less.

Description

TECHNICAL FIELD The present invention relates to a heat dissipating filler, a resin composition, and a resin molded body. RELATED ART Aluminum nitride (AIN) is an insulator with high heat conductivity and is therefore used as an insulating heat dissipating material for electronic devices. For example, AIN sintered bodies obtained by sintering AIN have a thermal expansion coefficient similar to that of silicon (Si), thereby making them suitable for use as heat sinks or substrates for silicon-based semiconductor devices. Meanwhile, use of particle-dispersed composite materials, such as resin molded bodies containing dispersed AIN particles, has also been proposed. Adding insulating fillers such as spherical ceramics is known as a method for improving the heat conductivity of resin parts. To improve the heat conductivity, it is important to increase contact efficiency between the fillers and form a network (heat dissipating path) of the fillers. For example, a resin molded body that has the heat conductivity, and moldability and processability has been proposed. Such a resin molded body contains an anisotropically shaped AIN filler formed into a fibrous, in which AIN single crystal particles are fused together to form the fibrous anisotropically shaped AIN filler, together with isotropically shaped particles (for example, see Patent Document 1). Further, a resin composition made of an epoxy resin or a silicone resin containing AIN whiskers has been proposed, which suppresses the inclusion of impurities and thus the decrease in the heat conductivity (for example, see Patent Document 2). In these resin molded bodies, by dispersing the AIN whiskers with a high aspect ratio in the resin molded body so that they are oriented in random directions along their length, contact density between the AIN whiskers can be increased, thereby imparting the high heat conductivity to the resin molded body. However, it has been difficult to sufficiently suppress overall thermal resistance. Further, for example, when the resin molded body is formed into a sheet, even if an in-plane heat conductivity is excellent, it has not been possible to achieve sufficiently excellent heat conductivity in the thickness direction of the sheet. PRIOR ART DOCUMENT PATENT DOCUMENT Patent document 1: JP-A-2010-235842Patent document 2: JP-A-2016-145120 SUMMARY OF THE INVENTION PROBLEM TO BE SOLVED BY THE INVENTION It is an object of the present invention to provide a heat dissipating filler that can reduce overall thermal resistance and is suitable for use in production of a resin molded body that has excellent heat conductivity not only in an in-plane direction but also in a thickness direction. It is another object of the present invention to provide a resin composition that can reduce the overall thermal resistance and is suitable for use in the production of the resin molded body that has the excellent heat conductivity not only in the in-plane direction but also in the thickness direction. It is the other object of the present invention to provide the resin molded body that can reduce the overall thermal resistance and has the excellent heat conductivity not only in the in-plane direction but also in the thickness direction. MEANS FOR SOLVING THE PROBLEM Such an object is achieved by the present inventions (1) to (12) described below. (1) A heat dissipating filler used for manufacturing a resin molded body, the heat dissipating filler comprising: first heat conductive particles each having a particle size of 10 µm or more and 150 µm or less;second heat conductive particles each having a particle size of 0.1 µm or more and less than 10 µm; andaluminum nitrides formed into a fibrous shape,wherein, when a total amount of the first heat conductive particles, the second heat conductive particles and the aluminum nitrides formed into the fibrous shape is 100 parts by volume, the heat dissipating filler contains the first heat conductive particles in a ratio of 30 parts by volume or more and 80 parts by volume or less, the second heat conductive particles in a ratio of 5 parts by volume or more and 50 parts by volume or less and the aluminum nitrides formed into the fibrous shape in a ratio of 1 part by volume or more and 40 parts by volume or less.(2) The heat dissipating filler described in the above-mentioned item (1), wherein the first heat conductive particles contain at least one selected from the group consisting of aluminum nitride, boron nitride and alumina.(3) The heat dissipating filler described in the above-mentioned item (1) or (2), wherein the second heat conductive particles contain at least one selected from the group consisting of aluminum nitride, alumina and silica.(4) The heat dissipating filler described in any one of the above-mentioned items (1) to (3), wherein a length in a long axis direction of the aluminum nitrides formed into the fibrous shape is 1.0 µm or more and 5.0 cm or less.(5) The heat dissipating filler described in