Phosphor and light-emitting device

Patent metadata

Field	Value
Publication number	US-11377594-B2
Application number	US-201917272827-A
Country	US
Kind code	B2
Filing date	Aug 22, 2019
Priority date	Sep 12, 2018
Publication date	Jul 5, 2022
Grant date	Jul 5, 2022

Abstract

A β-type sialon phosphor represented by the following expression 1, in which D50 is 10 μm or less, and values of D10, D50, and D90 satisfy a relationship of the following expression 2 with respect to D10, D50, and D90 (each unit is [μm]) on a volume frequency basis as measured according to a laser diffraction/scattering method. Expression 1: Si12-aAlaObN16-b:Eux (wherein 0<a≤3; 0<b≤3; 0<x≤0.1), expression 2: (D90−D10)/D50<1.6 (wherein the D10, D50, and D90 (each unit is [μm]) on a volume frequency basis as measured according to the laser diffraction/scattering method.

First claim

The invention claimed is:

1. A β-type sialon phosphor represented by the following expression 1, wherein D50 is 4.3 μm or less, and values of D10, D50, and D90 satisfy a relationship of the following expression 2 with respect to D10, D50, and D90 (each unit is [μm]) on a volume frequency basis as measured according to a laser diffraction/scattering method:
Si 12-a Al a O b N 16-b :Eu x   Expression 1

where 0<a≤3; 0<b≤3; 0<x≤0.1
( D 90− D 10)/ D 50<1.6  Expression 2

where the D10, D50, and D90 (each unit is [μm]) on a volume frequency basis as measured according to the laser diffraction/scattering method are each a measurement value obtained with a liquid obtained by loading 0.5 g of a phosphor for measurement, into 100 ml of a solution of 0.05% by weight of sodium hexametaphosphate mixed in ion-exchange water, and subjecting the resultant to a dispersing treatment for 3 minutes with an ultrasonic homogenizer at an oscillation frequency of 19.5±1 kHz and an amplitude of vibration of 32±2 μm, with a chip being placed at a central portion of the liquid, and
an average particle size D BET [μm] calculated from a specific surface area measured according to a BET method and the D50 [μm] measured according to a laser diffraction/scattering method, of the β-type sialon phosphor, satisfy a relationship of the following expression 3:
D 50/ D BET <2.1.  Expression 3

2. The β-type sialon phosphor according to claim 1 , wherein a diffuse reflectivity of light at a wavelength of 800 nm is 95% or more.

3. The β-type sialon phosphor according to claim 1 , wherein a light absorptivity of light at a wavelength of 600 nm is 6% or less.

4. A light-emitting device comprising a LED, a phosphor sheet, or a phosphor plate comprising the β-type sialon phosphor according to claim 1 .

Assignees

• Denka Company Ltd

Inventors

• Kobayashi Keita
• Mitani Shunsuke
• Kondo Ryousuke
• Sugita Kazuya
• Matsufuji Takuya
• Kajiyama Akihisa

Classifications

• H10H20/851

  Wavelength conversion means · CPC title

• H10H20/8512 Primary

  Wavelength conversion materials · CPC title

• H10H20/882

  Scattering means (H10H20/82 takes precedence) · CPC title

• C09K11/77348 Primary

  Silicon Aluminium Nitrides or Silicon Aluminium Oxynitrides · CPC title

• C09K11/64

  containing aluminium · CPC title