CERAMIC PHOSPHOR PLATE AND LIGHTING DEVICE INCLUDING THE SAME

• US 20150198303A1
• Filed: 01/12/2015
• Published: 07/16/2015
• Est. Priority Date: 01/13/2014
• Status: Active Grant

• Current Assignee: LG Innotek Company Limited (LG Corporation)
• Original Assignee: LG Innotek Company Limited (LG Corporation)
• Inventors: LEE, In Jae, PARK, Jin Gyeong, KIM, Won Jin
• Granted Patent: US 9,995,458 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: C09K 11/02 Use of particular materials as binders, particle coatings or suspension media therefor
• CPC Class Codes: C09K 11/08 containing inorganic luminescent materials
• CPC Class Codes: F21V 9/38 Combination of two or more photoluminescent elements of different materials
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 33/504 Elements with two or more wavelength conversion materials
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil
• CPC Class Codes: Y10T 428/24926 including ceramic, glass, porcelain or quartz layer
• CPC Class Codes: Y10T 428/252 Glass or ceramic [i.e., fired or glazed clay, cement, etc.] [porcelain, quartz, etc.]

Abstract

Provided is a ceramic phosphor plate including a first phosphor layer containing a short-wave phosphor in a transparent ceramic matrix and a second phosphor layer containing a long-wave phosphor, thereby enabling the reduction of a production cost by reducing an amount used of the high-priced long-wave phosphor (red phosphor).

Claims

1. A ceramic phosphor plate, comprising:

a first phosphor layer containing a short-wave phosphor in a transparent ceramic matrix; and

a second phosphor layer containing a long-wave phosphor.

2. The ceramic phosphor plate of claim 1, wherein the short-wave phosphor is a phosphor having a wavelength of 510 to 580 nm.

3. The ceramic phosphor plate of claim 1, wherein the long-wave phosphor is a phosphor having a wavelength of 580 to 680 nm.

4. The ceramic phosphor plate of claim 1, wherein the transparent ceramic matrix is composed of a borate-based ceramic, a phosphate-based ceramic or an aluminum oxide-based ceramic.

5. The ceramic phosphor plate of claim 1, wherein the short-wave phosphor is contained in an amount of 1 to 10 wt % in the transparent ceramic matrix.

6. The ceramic phosphor plate of claim 1, wherein the second phosphor layer has a structure in which a paste including the long-wave phosphor is stacked on one surface of the first phosphor layer.

7. The ceramic phosphor plate of claim 6, wherein the paste comprises a matrix composed of a silicate-based ceramic or a polymer.

8. The ceramic phosphor plate of claim 6, wherein the long-wave phosphor is contained in an amount of 15 to 30 wt % in the paste.

9. The ceramic phosphor plate of claim 1, wherein the second phosphor layer is configured such that a phosphor pattern is formed to partially occupy an area of one surface of the first phosphor layer.

10. The ceramic phosphor plate of claim 9, wherein the phosphor pattern of the second phosphor layer has a total area of 20 to 100% compared to the area of the one surface of the first phosphor layer.

11. The ceramic phosphor plate of claim 9, wherein the phosphor pattern is configured such that an area of each pattern ranges from 500 μ

m² to 10⁶ μ

m²

12. The ceramic phosphor plate of claim 1, wherein the first phosphor layer or the second phosphor layer contains 5 to 30 parts by weight of at least one powdered inorganic phosphor and 0.5 to 15 parts by weight of a binder compound containing at least one silicate and cross-linked by heat treatment with respect to 100 parts by weight of a transparent ceramic powder.

13. The ceramic phosphor plate of claim 12, wherein an average particle size of the transparent ceramic powder ranges from 1 to 50 μ

m.

14. The ceramic phosphor plate of claim 12, wherein the transparent ceramic powder is at least one kind of silicate-based powder selected from the group consisting of sodium borosilicate, aluminosilicate, zinc borosilicate, and barium zinc silicate.

15. The ceramic phosphor plate of claim 12, wherein the inorganic phosphor is at least one phosphor selected from the group consisting of a ruthenium aluminum garnet (LuAG)-based phosphor, a yttrium aluminum garnet (YAG)-based phosphor, a silicate-based phosphor, a sulfide-based phosphor, and a nitride-based phosphor.

16. The ceramic phosphor plate of claim 12, wherein the binder compound is at least one compound selected from the group consisting of tetraethyl orthosilicate (TEOS), tetramethyl orthosilicate, tetrapropyl orthosilicate, and tetraisopropyl orthosilicate.

17. The ceramic phosphor plate of claim 1, wherein the first phosphor layer or the second phosphor layer is formed by firing a phosphor-transparent composite composition containing at least one powdered inorganic phosphor dispersed in transparent ceramic powder and a cross-linking agent cross-linked by heat treatment in at least two steps, and has a porosity of less than 1%.

18. The ceramic phosphor plate of claim 17, wherein a surface roughness is 0.2 μ

m or less.

19. The ceramic phosphor plate of claim 17, wherein the ceramic phosphor plate has a curvature strength of 100N/mm² or more.

20. A lighting device, comprising a ceramic phosphor plate of claim 1.