Method of producing beta-sialon fluorescent material
AssigneeNichia Corporation
InventorsKenichi Aoyagi, Takashi Kaide, Yuya Takahashi, Shoji Hosokawa
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Abstract
Provided a method of producing a β-sialon fluorescent material having excellent emission intensity. The method includes providing a first composition containing aluminum, an oxygen atom, and a europium-containing silicon nitride, heat treating the first composition, contacting the heat-treated composition and a basic substance to obtain a second composition, and contacting the second composition resulting from contacting the heat-treated composition with the basic substance and an acidic liquid medium containing an acidic substance.
Claims21
A method of producing a β-sialon fluorescent material, the method comprising:
- providing a first composition containing aluminium, an oxygen atom, and a europium-containing silicon nitride;
- heat treating the first composition;
- contacting the heat-treated composition and a basic substance to obtain a second composition;
- and
- acid-treating the second composition comprising contacting the second composition and an acidic liquid medium containing an acidic substance to obtain an acid-treated product,
- wherein the acidic liquid medium contains water and hydrogen chloride as the acidic substance,
- wherein the acidic liquid medium contains the acidic substance in an amount of from 0.1% by weight to 5% by weight,
- wherein σ log of the β-sialon fluorescent material after the acid treating is a range of 0.279 to 0.299,
- wherein the method further comprises, before heat treating the first composition, strongly pulverizing the first composition with a europium compound to obtain a pulverized product containing the europium compound and heat treating in a nitrogen atmosphere the pulverized product containing the europium compound, and
- wherein the pulverized product has a specific surface area of 0.20 m2/g or more.
Dependencies are inferred from the claim text.