BORON-NITRIDE POWDER AND RESIN COMPOSITION CONTAINING SAME

• US 20160060112A1
• Filed: 03/07/2014
• Published: 03/03/2016
• Est. Priority Date: 03/07/2013
• Status: Active Grant

• Current Assignee: Denka Company Limited
• Original Assignee: Denki Kagaku Kogyo Kabushiki Kaisha (TDK Corporation)
• Inventors: NISHI, Taiki, IKARASHI, Koki, MITSUNAGA, Toshikatsu
• Granted Patent: US 9,656,868 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: C01B 21/064 with boron
• CPC Class Codes: C01B 21/0648 After-treatment, e.g. grinding, purification transformation of hexagonal into cubic or wurtzitic boron nitride C04B35/5831
• CPC Class Codes: C01P 2002/74 by peak-intensities or a ratio thereof only
• CPC Class Codes: C01P 2002/76 by a space-group or by other symmetry indications
• CPC Class Codes: C01P 2004/03 obtained by SEM
• CPC Class Codes: C01P 2004/32 Spheres
• CPC Class Codes: C01P 2004/50 Agglomerated particles
• CPC Class Codes: C01P 2004/61 Micrometer sized, i.e. from 1-100 micrometer
• CPC Class Codes: C01P 2006/14 Pore volume
• CPC Class Codes: C01P 2006/16 Pore diameter
• CPC Class Codes: C01P 2006/32 Thermal properties
• CPC Class Codes: C01P 2006/80 Compositional purity
• CPC Class Codes: C08K 2003/385 Binary compounds of nitrogen with boron
• CPC Class Codes: C08K 3/38 Boron-containing compounds
• CPC Class Codes: C08L 101/00 Compositions of unspecified macromolecular compounds
• CPC Class Codes: C09K 5/14 Solid materials, e.g. powdery or granular

Abstract

Provided is a boron-nitride powder that is suitable for use in a resin composition for transmitting heat from a heat-producing electronic component such as a power device to a heat-dissipating member. The boron-nitride powder reduces thermal-conductivity anisotropy and thermal contact resistance, resulting in high thermal conductivity, and contains boron-nitride particles each consisting of hexagonal boron-nitride primary particles joined together. The boron-nitride powder, which is an aggregate of said boron-nitride particles, exhibits a mean sphericity of at least 0.70, a mean particle diameter of 20-100 μm, a porosity of 50-80%, a mean pore diameter of 0.10-2.0 μm, a maximum pore diameter of at most 10 μm, and a calcium content of 500-5,000 ppm. Under X-ray powder diffraction, the graphitization index of the boron-nitride powder is preferably between 1.6 and 4.0, inclusive, and the peak intensity ratio (I(002)/I(100)) between the (002) plane and the (100) plane is preferably at most 9.0.

Claims

1. A boron-nitride powder, containing boron-nitride particles each composed of hexagonal boron-nitride primary particles joined together, which is an aggregate of the boron-nitride particles, wherein

the boron-nitride powder has a mean sphericity of 0.70 or more, a mean particle diameter of 20 to 100 μ

m, a porosity of 50 to 80%, a mean pore diameter of 0.10 to 2.0 μ

m, a maximum pore diameter of 10 μ

m or less, and a calcium content of 500 to 5,000 ppm.

2. The boron-nitride powder according to claim 1, wherein

a graphitization index measured by powder X-ray diffraction method is 1.6 to 4.0, and a peak intensity ratio I(002)/I(100) of (002) plane to (100) plane is 9.0 or less.

3. The boron-nitride powder according to claim 1, wherein

amorphous boron-nitride having a mean particle diameter of 2 to 6 μ

m and the hexagonal boron-nitride having a mean particle diameter of 8 to 16 μ

m are used as raw materials, and

a mixing ratio thereof, that is, the ratio of the amorphous boron-nitride to the hexagonal boron-nitride is 60;

40 to 90;

10 on a mass basis.

4. A resin composition characterized by containing a resin and the boron-nitride powder according to claim 1.

5. The resin composition according to claim 4, wherein

an elastic modulus of the boron-nitride particles is 5 to 35 MPa, and the boron-nitride particles are in surface contact with each other.

6. A resin composition containing a resin and the boron-nitride powder according to claim 2.

7. A resin composition containing a resin and the boron-nitride powder according to claim 3.

8. The resin composition according to claim 6, wherein

an elastic modulus of the boron-nitride particles is 5 to 35 MPa, and the boron-nitride particles are in surface contact with each other.

9. The resin composition according to claim 7, wherein an elastic modulus of the boron-nitride particles is 5 to 35 MPa, and the boron-nitride particles are in surface contact with each other.