WAVELENGTH CONVERSION MEMBER, LIGHT-EMITTING DEVICE, AND IMAGE DISPLAY DEVICE

• Main Authors: KIJIMA NAOTO, YAMASHITA YOSHINAGA, YOSHIDA TOMOKAZU, YAMAUCHI YOHEI, SHIODA YUUKI, HOSOKAWA SHOJI
• Format: Patent
• Language: English; Japanese
• Published: 06.01.2023
• Subjects: ADHESIVES; BASIC ELECTRIC ELEMENTS; CHEMISTRY; DYES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FORELSEWHERE; METALLURGY; MISCELLANEOUS APPLICATIONS OF MATERIALS; MISCELLANEOUS COMPOSITIONS; NATURAL RESINS; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; PAINTS; PHYSICS; POLISHES; SEMICONDUCTOR DEVICES

To provide a wavelength conversion member having good uniformity of luminescent color.SOLUTION: A wavelength conversion member includes a wavelength conversion layer containing a fluoride phosphor, quantum dots, a surfactant, and a resin. The fluoride phosphor contains fluoride particles having a specific composition and having an average particle size in a range from 0.1 μm or more to less than 10 μm and a maximum particle size in a range from 1 μm or more to 18 μm or less, with a ratio of the maximum particle size to the average particle size being greater than 1. The quantum dots include at least one selected from a first crystalline nanoparticle and a second crystalline nanoparticle. The first crystalline nanoparticle has a composition containing alkali metal ions or the like, lead or the like and halogen ions or the like. The first crystalline nanoparticles have a median diameter in a range from 3 nm or more to 15 nm or less and emit light having an emission peak at a wavelength in a range from 510 nm or more to 535 nm or less when irradiated with light having a wavelength of 450 nm, where a full width at half maximum of the emission peak is in a range from 10 nm or more to 30 nm or less. The second crystalline nanoparticle includes a chalcopyrite-type crystalline structure, where a full width at half maximum of the emission peak of the second crystalline nanoparticle is 45 nm or less.SELECTED DRAWING: Figure 1 【課題】発光色の均一性に優れる波長変換部材を提供する。【解決手段】フッ化物蛍光体、量子ドット、界面活性剤及び樹脂を含む波長変換層を備える波長変換部材である。フッ化物蛍光体は特定の組成を有し、平均粒径が０．１μｍ以上１０μｍ未満、最大粒径が１μｍ以上１８μｍ以下であり、最大粒径の平均粒径に対する比が１より大きいフッ化物粒子を含む。量子ドットは、第１の結晶性ナノ粒子及び第２の結晶性ナノ粒子から選択される少なくとも１種を含む。第１の結晶性ナノ粒子はアルカリ金属イオン等と鉛等とハロゲンイオン等とを含む組成を有し、メジアン径が３ｎｍ以上１５ｎｍ以下で、波長４５０ｎｍの光照射により波長５１０ｎｍ以上５３５ｎｍ以下に発光ピークを有し、発光ピークの半値幅が１０ｎｍ以上３０ｎｍ以下である。第２の結晶性ナノ粒子はカルコパイライト型の結晶構造を含み、発光ピークの半値幅が４５ｎｍ以下である。【選択図】図１