JP-7857513-B1 - Boron nitride powder, inorganic filler, resin composition, and resin molded article

Abstract

[Problem] To provide a boron nitride powder that can provide a resin molded article with excellent heat dissipation and excellent insulation properties. [Solution] A boron nitride powder is provided, which includes aggregated particles composed of aggregated primary particles of hexagonal boron nitride, wherein the orientation index is 12 or less, and in the Raman spectrum obtained by irradiating the aggregated particles with a laser of wavelength 532 nm, the peak showing the maximum intensity is located in the region of Raman shift 1360 cm⁻¹ to 1370 cm⁻¹ , and the full width at half maximum of the peak is 30 cm⁻¹ or less. [Selection Diagram] None

Inventors

• 細谷 周平
• 田中 孝明
• 田中 玲偉

Assignees

• デンカ株式会社

Dates

Publication Date

20260512

Application Date

20260318

Claims (9)

1. A boron nitride powder containing aggregated particles composed of aggregated primary particles of hexagonal boron nitride, The orientation index is 12 or less. Boron nitride powder, wherein in the Raman spectrum obtained by irradiating the aggregated particles with a laser of wavelength 532 nm, the peak showing maximum intensity is located in the region of Raman shift 1360 cm⁻¹ to 1370 cm⁻¹ , and the full width at half maximum of the peak is 30 cm⁻¹ or less.
2. The boron nitride powder according to claim 1, wherein the 50% penetration particle size (D50) in the particle size distribution measured by laser diffraction scattering is 1 to 150 μm.
3. The boron nitride powder according to claim 1, wherein the crushing strength of the aggregated particles is 5 MPa or more.
4. The boron nitride powder according to claim 1, wherein the graphitization index is 2.3 or less.
5. Boron nitride powder according to any one of claims 1 to 4, An inorganic filler comprising an aluminum compound powder containing at least one selected from the group consisting of aluminum oxide and aluminum nitride.
6. A resin composition comprising boron nitride powder according to any one of claims 1 to 4, and a resin.
7. A resin composition comprising the inorganic filler described in claim 5 and a resin.
8. A resin molded article comprising boron nitride powder according to any one of claims 1 to 4 and a resin.
9. A resin molded article comprising the inorganic filler described in claim 5 and a resin.

Description

This disclosure relates to boron nitride powder, inorganic fillers, resin compositions, resin molded articles, etc. Boron nitride powder possesses high thermal conductivity and insulating properties, and is widely used in applications such as thermal conductive fillers and insulating fillers. In particular, boron nitride powder is used as a filler in heat dissipation components where high thermal conductivity is required (for example, Patent Document 1, etc.). Japanese Patent Publication No. 2000-154265 The following describes embodiments of this disclosure. However, these embodiments are illustrative examples for illustrating this disclosure and are not intended to limit this disclosure to the following. In this specification, numerical ranges indicated by the symbol "～" include both a lower and upper limit. That is, a numerical range indicated by "x～y" means x or greater and y or less. Unless otherwise specified, the materials exemplified herein may be used individually or in combination of two or more. The content of each component in a composition refers to the total amount of any multiple substances present in the composition, unless otherwise specified, if multiple substances corresponding to each component exist in the composition. A boron nitride powder according to one embodiment of this disclosure includes aggregated particles composed of aggregated primary particles of hexagonal boron nitride. In a Raman spectrum obtained by irradiating these aggregated particles with a 532 nm wavelength laser, the peak showing the maximum intensity (hereinafter also referred to as "peak A") is located in the region of Raman shift 1360 cm⁻¹ to 1370 cm⁻¹ , and the full width at half maximum of peak A is 30 cm⁻¹ or less. In this specification, the range of the Raman shift (horizontal axis) in the Raman spectrum is 900 to 3000 cm⁻¹ . Furthermore, the peak intensity of the Raman spectrum refers to the height of the peak from the baseline. Measurement of boron nitride powder by Raman spectroscopy shall be performed by the following method. Specifically, first, a cross-sectional sample of aggregated particles in the powder is prepared using a cross-sectional sample preparation device. Next, the obtained cross-sectional sample is used as the measurement target, and a Raman spectrum (horizontal axis: Raman shift (unit: cm⁻¹ ), vertical axis: intensity) is obtained by measuring with a Raman spectrometer under the measurement conditions described in the examples. As a cross-sectional sample preparation device, for example, the "CP-9010" (product name) manufactured by JEOL Ltd. can be used. As a Raman spectrometer, for example, the "Raman Microscope XploRA" (product name) manufactured by Horiba, Ltd. can be used. The full width at half maximum (FWHM) of peak A is 30 cm⁻¹ or less. Boron nitride powder with a FWHM of peak A of 30 cm⁻¹ or less exhibits high crystal periodicity in the in-plane and stacking directions, and suppresses phonon scattering. Therefore, resin molded bodies containing this boron nitride powder have excellent heat dissipation. The FWHM of peak A may be greater than 0 cm⁻¹ , 1 cm⁻¹ or more, 3 cm⁻¹ or more, 5 cm⁻¹ or more, 8 cm⁻¹ or more, 12 cm⁻¹ or more, 15 cm⁻¹ or more, or 20 cm⁻¹ or more. From the viewpoint of further improving the heat dissipation of the resin molded body, the FWHM of peak A may be 28 cm⁻¹ or less, 25 cm⁻¹ or less, 23 cm⁻¹ or less, 20 cm⁻¹ or less, 15 cm⁻¹ or less, or 11 cm⁻¹ or less. The full width at half maximum (FWHM) of peak A may be adjusted within the above range, for example, 1 to 30 cm⁻¹ , 3 to 28 cm⁻¹ , or 5 to 25 cm⁻¹ . The FWHM of peak A can be adjusted by the pressure in the nitriding process, the firing temperature in the firing process, etc., as described later. If there are multiple "peaks showing maximum intensity" in the Raman spectrum, the "peak showing maximum intensity (peak A)" in this specification refers to the peak that is closest to a Raman shift of 1366 cm⁻¹ among those peaks. The boron nitride powder described above may contain primary particles of hexagonal boron nitride and aggregated particles composed of multiple aggregated primary particles of hexagonal boron nitride. In this specification, aggregated particles refer to secondary particles that exist in an aggregated state of multiple primary particles (single particles), where the c-axis direction of each primary particle is random. The aggregated state of primary particles can be confirmed, for example, by a scanning electron microscope (SEM). Aggregated particles may be approximately spherical. In aggregated particles, primary particles may be strongly bound to each other. The particle size of boron nitride powder that passes through 50% of the particle size distribution measured by laser diffraction scattering (D50) may be 1 μm or more, 5 μm or more, 10 μm or more, 15 μm or more, 18 μm or more, 20 μm or more, 25 μm or more, 30 μm or more, 35 μm or more, 40 μm or more, 43 μm or more, or 44.5 μm or mo