Method of producing beta-sialon fluorescent material
AssigneeNichia Corporation
InventorsKenichi Aoyagi, Takashi Kaide, Motoharu Morikawa, Shoji Hosokawa
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Abstract
Provided is a method of producing a β-sialon fluorescent material having a high light emission intensity and an excellent light emission luminance. The method includes preparing a calcined product having a composition of β-sialon containing an activating element; grinding the calcined product to obtain a ground product; and heat-treating the ground product to obtain a heat-treated product. A specific surface area of the ground product is 0.2 m2/g or more.
Claims20
A method of producing a β-sialon fluorescent material, comprising:
- preparing a calcined product having a composition of β-sialon containing an activating element by calcining a raw material mixture containing a first compound containing an activating element;
- grinding the calcined product together with a second compound containing an activating element in the absence of another raw material for making β-sialon to obtain a ground product, wherein the ground product does not contain a raw material for making β-sialon other than the second compound containing the activating element;
- and
- heat-treating the ground product to obtain a heat-treated product, wherein
- a specific surface area of the ground product is 0.25 m2/g or more,
- wherein the first compound containing the activating element and the second compound containing the activating element do not have a composition of a β-sialon containing an activating element, and
- a molar ratio of the activating element contained in the second compound containing the activating element is smaller than a ratio of the activating element in the first compound containing the activating element in the raw material.
A method of producing a β-sialon fluorescent material, comprising:
- preparing a calcined product having a composition of β-sialon containing an activating element by calcining a raw material mixture containing a first compound containing an activating element;
- grinding the calcined product together with a second compound containing an activating element in the absence of a raw material for making β-sialon other than the second compound containing the activating element to obtain a ground product, wherein the ground product does not contain a raw material for making β-sialon other than the second compound containing the activating element;
- and
- heat-treating the ground product to obtain a heat-treated product, wherein
- the grinding and heat-treating steps are repeated two times or more in this order, and
- in at least one grinding step, an average particle diameter of the ground product is 40 μm or less, and a specific surface area of the ground product is 0.25 m2/g or more,
- wherein the first compound containing the activating element and the second compound containing the activating element do not have a composition of a β-sialon containing an activating element, and
- a molar ratio of the activating element contained in the second compound containing the activating element is smaller than a ratio of the activating element in the first compound containing the activating element in the raw material.
Dependencies are inferred from the claim text.