# US 2019/0355879 A1 · Phosphor sheet, white light source device including the phosphor sheet, and display device including the white light source device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0355879 A1 - Document ID: US20190355879A1 - Status: Published application - Kind: A1 - Application number: 16/519,181 - Filed: 2019-07-23 - Published: 2019-11-21 - Earliest claimed: 2015-07-10 - Assignees: Dexerials Corporation - Applicants: Dexerials Corporation - Inventors: Noritaka SATO; Koichi KISHIMOTO; Tomomitsu HORI; Yasushi ITO - Web page: https://patentgrep.com/patent/US20190355879A1 ## CPC - H10H 20/8512: {Wavelength conversion materials} - C09K 11/02: Use of particular materials as binders, particle coatings or suspension media therefor - C09K 11/06: containing organic luminescent materials - C09K 11/567: {with alkaline earth metals} - C09K 11/625: {with alkaline earth metals} - G02B 5/003: {Light absorbing elements} - G02B 5/20: Filters (polarising elements G02B5/30) - G02B 5/22: Absorbing filters {(G02B5/201 - G02B5/208 take precedence)} - G02F 1/133603: {with LEDs} - H10H 20/851: Wavelength conversion means - C09K 2211/183: of the refractory metals, i.e. Ti, V, Cr, Zr, Nb, Mo, Hf, Ta or W - H10H 20/0361: {of wavelength conversion means} - Y02B 20/00: Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps - H10H: INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - G02F: OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS ## Abstract Disclosed are a phosphor sheet capable for converting light from LEDs into white light, a white light source device including the phosphor sheet, and a display device including the white light source device. The disclosed phosphor sheet includes a phosphor layer containing at least a phosphor and a resin; and a pair of transparent substrates sandwiching the phosphor layer. The phosphor sheet comprises a coloring material having an absorption maximum wavelength of at least one of from 480 nm to 510 nm or from 570 nm to 620 nm. The coloring material is contained in the phosphor layer. The transparent substrates are adhered to both surfaces of the phosphor layer. the phosphor layer has a thickness of 20 μm to 200 μm. An indicator of the usage amount of the coloring material defined by the following formula is 0.003 to 0.028: (indicator of the usage amount of the coloring material)=((blending amount of the coloring material in the phosphor layer)/(blending amount of a resin in the phosphor layer))×(the thickness of the phosphor layer (μm)). ## Claims ### Claim 1 A phosphor sheet for converting light from LEDs into white light, comprising: a phosphor layer containing at least a phosphor and a resin; and a pair of transparent substrates sandwiching the phosphor layer, wherein the phosphor sheet comprises a coloring material having an absorption maximum wavelength of at least one of from 480 nm to 510 nm or from 570 nm to 620 nm, the coloring material is contained in the phosphor layer, the transparent substrates are adhered to both surfaces of the phosphor layer, the phosphor layer has a thickness of 20 μm to 200 μm, and an indicator of the usage amount of the coloring material defined by the following formula is 0.003 to 0.028: (indicator of the usage amount of the coloring material)=((blending amount of the coloring material in the phosphor layer)/(blending amount of a resin in the phosphor layer))×(the thickness of the phosphor layer (μm)). ### Claim 2 (depends on 1) The phosphor sheet according to claim 1, wherein the coloring material has an absorption maximum wavelength of at least one of from 570 nm to 620 nm. ### Claim 3 (depends on 1) The phosphor sheet according to claim 1, wherein the transparent substrates have a thickness of 10 μm to 100 μm. ### Claim 4 (depends on 1) The phosphor sheet according to claim 1, wherein each of the transparent substrates is a water vapor gas barrier film. ### Claim 5 (depends on 4) The phosphor sheet according to claim 4 having a water vapor permeability of 0.05 g/m2/day to 5 g/m2/day. ### Claim 6 (depends on 1) The phosphor sheet according to claim 1, wherein the coloring material has a half-value width of 50 nm or less. ### Claim 7 (depends on 1) The phosphor sheet according to claim 1, wherein the phosphor comprises at least a sulfide phosphor. ### Claim 8 (depends on 1) The phosphor sheet according to claim 1, wherein the LEDs are blue LEDs. ### Claim 9 (depends on 8) The phosphor sheet according to claim 8, wherein the phosphor is a red sulfide phosphor and a green sulfide phosphor. ### Claim 10 (depends on 9) The phosphor sheet according to claim 9, wherein the red sulfide phosphor is a calcium sulfide phosphor and the green sulfide phosphor is a thiogallate phosphor. ### Claim 11 (depends on 1) The phosphor sheet according to claim 1, wherein the LEDs are magenta LEDs. ### Claim 12 (depends on 11) The phosphor sheet according to claim 11, wherein the phosphor is a green sulfide phosphor alone. ### Claim 13 (depends on 11) The phosphor sheet according to claim 11, wherein the magenta LEDs each use a red light emitting phosphor comprising at least one of a fluoride phosphor represented by Ax(M1-y, Mny)Fz and a nitride phosphor, where A is at least one of K (potassium) or Cs (cesium), M is at least one of Si (silicon) or Ti (titanium), and x, y, and z are numerical values satisfying 1.7≤x≤2.1, 0