JP2011116974A - Blue light-emitting phosphor and light-emitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light-emitting device which uses a phosphor represented by composition formula: Sr<SB>3-x</SB>MgSi<SB>2</SB>O<SB>8</SB>:Eu<SB>x</SB>as a blue light source and which exhibits high luminance. <P>SOLUTION: In the light-emitting device which is provided with both an excitation light source that emits vacuum ultraviolet rays including a ray having a wavelength of 172 nm and a phosphor which can be excited by the vacuum ultraviolet rays emitted from the excitation light source to emit blue light, the phosphor is a substance represented by composition formula: Sr<SB>3-x</SB>MgSi<SB>2</SB>O<SB>8</SB>:Eu<SB>x</SB>, wherein x is 0.0090 to 0.025, and the substance further contains 0.00010 to 0.040 mol of W and/or Pb per mol of the substance. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present _{invention, Sr 3-x MgSi 2 O} 8: blue-emitting phosphor represented by a composition formula of Eu _x and the blue-emitting phosphor to a light emitting device used as a blue light emitting source.

  As a light emitting device that emits visible light by irradiating phosphor such as vacuum ultraviolet light or ultraviolet light and exciting the phosphor, an AC plasma display panel (AC type PDP), a cold cathode fluorescent lamp (CCFL) and white light emitting diode (white LED) are known.

The AC type PDP irradiates a blue light emitting phosphor, a green light emitting phosphor and a red light emitting phosphor with vacuum ultraviolet light generated by the discharge of Xe gas, respectively, and emits blue light emitted by exciting each phosphor, A light-emitting device that obtains an image by combining green light and red light. The light emission caused by the discharge of the Xe gas is mainly Xe resonance light emission and Xe ₂ molecular light emission. Resonant line emission generates vacuum ultraviolet light having a center wavelength of 146 nm (there is also a document described as 147 nm). In molecular beam light emission, vacuum ultraviolet light having a center wavelength of 172 nm (some documents are described as 173 nm) is generated.

  The CCFL irradiates the blue light emitting phosphor, the green light emitting phosphor and the red light emitting phosphor with ultraviolet light generated by the discharge of the Hg gas, and excites each phosphor to emit blue light, green light and red light. It is a light emitting device that obtains white light by mixing light. The wavelength of the ultraviolet light generated by the discharge of Hg gas is 254 nm.

  As a white LED, light having a peak in a wavelength range of 350 to 430 nm generated by applying a voltage to a semiconductor is irradiated to a blue light emitting phosphor, a green light emitting phosphor, and a red light emitting phosphor, and each phosphor is irradiated. A configuration in which white light is obtained by mixing blue light, green light and red light emitted by excitation is known.

When excited by light such as vacuum ultraviolet light or ultraviolet light as a blue emitting phosphor emitting blue _{light, Sr 3-x MgSi 2 O} 8: phosphor represented by a composition formula of Eu _x (hereinafter, SMS phosphor also referred to) and _{Ba 1-x MgAl 10 O 17} : phosphor represented by a composition formula of Eu _x (hereinafter, also referred to as BAM phosphor) is known. The SMS phosphor has an advantage that it has a long lifetime compared with the BAM phosphor, with less decrease in emission luminance over time due to irradiation with vacuum ultraviolet light or ultraviolet light.

  Patent Document 1 describes that part of Mg of the SMS phosphor is replaced with a Group 5 or Group 6 element in order to further prevent a decrease in emission luminance over time due to excitation light irradiation. W is described as an example of the Group 5 and 6 elements. This Patent Document 1 describes that the amount of substitution of W is in the range of 0.003 to 0.006 in terms of the ratio of W to the total mole of Mg and W (W / (Mg + W)). Further, it is described that the Eu content is preferably in the range of 0.003 or more and 0.05 or less in terms of Eu with respect to the total moles of Sr and Eu (Eu / (Sr + Eu)). In the example of Patent Document 1, the effect of adding W is confirmed by the light emission luminance by excitation of vacuum ultraviolet light having a wavelength of 146 nm.

  In Patent Document 2, in order to improve the lifetime and luminance characteristics of a silicate phosphor used under vacuum ultraviolet excitation conditions, Cu, Ga, Ge, As, Ag, Cd, In, Sn, Sb are used as the phosphor. , Au, Hg, Tl, Pb, Bi and the like are described. The preferable range of the Eu content of the phosphor described in Patent Document 2 is 0.001 to 0.2 mol with respect to 1 mol of the phosphor, and the preferable amount of the additive element is the molar ratio with respect to Eu. 1 or less. In the example of Patent Document 2, the effect of adding the above elements is confirmed by the luminance of light emitted by excitation of vacuum ultraviolet light having a wavelength of 147 nm.

JP 2007-314644 A JP 2006-70187 A

  The SMS phosphors described in Patent Documents 1 and 2 are useful as a blue light emission source by exciting Xe resonance line emission (vacuum ultraviolet light having a wavelength of 146 nm or 147 nm) emitted by discharge of Xe gas. On the other hand, in the AC type PDP, in order to increase the light emission luminance, it has been studied to increase the amount of Xe gas filled in the panel and increase the amount of vacuum ultraviolet light generated by the discharge of Xe gas. When the Xe gas filling amount in the panel is increased, the emission amount of vacuum ultraviolet light having a wavelength of 172 nm due to molecular beam emission increases. For this reason, in the phosphor for AC type PDP, the improvement of the light emission luminance by excitation of the vacuum ultraviolet light with a wavelength of 172 nm is desired. In addition, there are many light-emitting devices that use light having a wavelength other than 146 nm as excitation light, such as CCFLs and white LEDs, as applications of SMS phosphors. However, according to the study of the present inventor, the additive elements described in the above-mentioned Patent Documents 1 and 2 are used as they are as UV light having a wavelength of 254 nm, which is used as excitation light for CCFLs, or as wavelength used as excitation light for white LEDs. It has been found that it does not work effectively to improve the emission luminance of the SMS phosphor due to excitation of light of 350 to 430 nm.

  Further, in a light emitting device such as an AC type PDP or CCFL, the phosphor is usually arranged as a phosphor layer on a substrate. This phosphor layer is generally formed by coating a phosphor dispersion on a substrate, then drying the coated film, and then firing the substrate at a temperature of 300 to 600 ° C. in the atmosphere. Some white LEDs are arranged as a phosphor layer in which a phosphor is dispersed in glass. This phosphor layer is generally formed by baking a dispersion of a phosphor and glass mixture in the atmosphere at a temperature of 300 ° C. or higher to melt the glass. Therefore, the phosphor is required to maintain high emission luminance even after the heat treatment in the air atmosphere.

  Therefore, an object of the present invention is to provide an SMS phosphor that exhibits high emission luminance even after heat treatment in an air atmosphere by excitation with vacuum ultraviolet light with a wavelength of 172 nm, ultraviolet light with a wavelength of 254 nm, and light with a wavelength of 350 to 430 nm. The object of the present invention is to provide a light emitting device with high emission brightness using an SMS phosphor as a blue light source.

The present inventors _{have, Sr 3-x MgSi 2 O} 8: In SMS phosphor represented by a composition formula of Eu _x, the addition of W and / or Pb to improve the light emission brightness after a heat treatment in an air atmosphere It is found that the Eu content (x value in the composition formula) differs from the optimum value of the addition amount of W and / or Pb depending on the wavelength of the excitation light. Alternatively, by setting the addition amount of Pb within the following range, an SMS phosphor exhibiting high emission luminance can be obtained by excitation with vacuum ultraviolet light with a wavelength of 172 nm, ultraviolet light with a wavelength of 254 nm, or light with a wavelength of 350 to 430 nm. As a result, the present invention was completed.

That is, the present _{invention, Sr 3-x MgSi 2 O} 8: is represented by a composition formula of Eu _x, x is a value in the range of 0.0090 to .025, W and the phosphor 1 mole It is a blue light-emitting phosphor for a light-emitting device that contains vacuum ultraviolet light including light having a wavelength of 172 nm, containing Pb in an amount in the range of 0.00010 to 0.040 mol.

The present invention also _{provides, Sr 3-x MgSi 2 O} 8: is represented by a composition formula of Eu _x, x is a value in the range of 0.025-.040, W and the phosphor 1 mol / Or it exists also in the blue light emission fluorescent substance for light-emitting devices which contains Pb in the quantity of the range of 0.00010-0.0075 mol, and uses the ultraviolet light containing light emission of wavelength 254nm as excitation light.

The present invention also _{provides, Sr 3-x MgSi 2 O} 8: is represented by a composition formula of Eu _x, x is a value in the range of 0.0090 to .040, W and the phosphor 1 mol / Alternatively, there is also a blue light-emitting phosphor for a light-emitting device containing Pb in an amount in the range of 0.00010 to 0.040 mol and having excitation light as light having a peak in a wavelength range of 350 to 430 nm.

The present invention is also a light emitting device including an excitation light source that emits vacuum ultraviolet light including light having a wavelength of 172 nm, and a phosphor that emits blue light when excited by vacuum ultraviolet light from the excitation light source. , phosphor _{is, Sr 3-x MgSi 2 O} 8: is represented by a composition formula of Eu _x, x is a value in the range of from .0090 to 0.025, W and the phosphor 1 mole There is also a light emitting device which is a phosphor containing Pb in an amount in the range of 0.00010 to 0.040 mol.

The present invention is also a light emitting device comprising: an excitation light source that emits ultraviolet light including light having a wavelength of 254 nm; and a phosphor that emits blue light when excited by ultraviolet light from the excitation light source. _{phosphor, Sr 3-x MgSi 2 O} 8: is represented by a composition formula of Eu _x, x is a value in the range of .025 to .040, W and / or the phosphor 1 mole There is also a light emitting device which is a phosphor containing Pb in an amount in the range of 0.00010 to 0.0075 mol.

The present invention is also a light emitting device including an excitation light source that emits light having a peak in a wavelength range of 350 to 430 nm, and a phosphor that emits blue light when excited by light from the excitation light source. , phosphor _{is, Sr 3-x MgSi 2 O} 8: is represented by a composition formula of Eu _x, x is a value in the range of from .0090 to .040, W and the phosphor 1 mole There is also a light emitting device which is a phosphor containing Pb in an amount in the range of 0.00010 to 0.040 mol.

  As is apparent from the results of Examples described later, the SMS phosphor of the present invention has higher emission luminance than a commercially available BAM phosphor after heat treatment at a temperature of 500 ° C. in an air atmosphere. Therefore, the light emitting device using the SMS phosphor of the present invention has a higher emission luminance of blue light than the light emitting device using the conventional BAM phosphor, or the light emitting device using the conventional BAM phosphor. In comparison, even if the emission luminance of blue light is the same, the amount of phosphor used can be reduced.

It is a perspective view of an example of an AC type plasma display panel according to the present invention. It is sectional drawing of an example of the cold cathode type | mold fluorescent lamp according to this invention. FIG. 3 is a cross-sectional view of an example of a white light emitting diode according to the present invention.

SMS phosphor of the present invention, the basic composition formula _{Sr 3-x MgSi 2 O 8} : represented by Eu _x. The SMS phosphor generally has a merwinite crystal structure. SMS phosphors in which a part of Sr is substituted with Ca or Ba are known, but the SMS phosphor used in the present invention does not substantially contain Ca or Ba substituted with Sr. It is preferable. Here, substantially not containing Ca or Ba means that the content of Ca and Ba is 0.01 mol or less per mol of the phosphor.

  The SMS phosphor of the present invention contains W and / or Pb. The Eu content of the SMS phosphor and the addition amount of W and / or Pb vary depending on the application of the SMS phosphor, that is, the wavelength of light that excites the SMS phosphor.

  The SMS phosphor for the light emitting device using the Xe gas under discharge as the excitation light source, such as the AC type PDP, that is, the excitation for the vacuum ultraviolet light including the light emission with a wavelength of 172 nm has the Eu content in 1 mol of the phosphor. It is in the range of 0.0090 to 0.025 mol (that is, x in the composition formula is in the range of 0.0090 to 0.025), and W and / or Pb is 0 with respect to 1 mol of the phosphor. Contained in an amount ranging from 0.0001 to 0.040 mol.

  The SMS phosphor for vacuum ultraviolet light whose excitation light includes light emission with a wavelength of 172 nm has a Eu content in the range of 0.010 to 0.025 mol, particularly 0.010 to 0.023 mol in 1 mol of the phosphor. A phosphor containing W in an amount in the range of 0.00075 to 0.0075 mol relative to 1 mol of the phosphor, or the Eu content in 1 mol of the phosphor is 0.0090 to 0 The phosphor is in the range of 0.025 mol, particularly in the range of 0.010 to 0.023 mol, and contains Pb in an amount in the range of 0.00050 to 0.040 mol with respect to 1 mol of the phosphor. Is preferred.

  For a light emitting device using Hg gas under discharge as an excitation light source, such as CCFL, that is, an SMS phosphor for excitation by ultraviolet light including light emission with a wavelength of 254 nm, the Eu content in 1 mol of the phosphor is 0.025. ˜0.040 mol (that is, x in the composition formula is in the range of 0.025 to 0.040), and W and / or Pb is 0.00010 to 1 mol of the phosphor. Contained in an amount in the range of 0.0075 mol.

  In the SMS phosphor for ultraviolet light whose excitation light includes light emission with a wavelength of 254 nm, the Eu content in 1 mol of the phosphor is in the range of 0.025 to 0.040 mol, particularly in the range of 0.028 to 0.040 mol. Or a phosphor containing W in an amount in the range of 0.00075 to 0.0075 mol with respect to 1 mol of the phosphor, or the Eu content in 1 mol of the phosphor is 0.025 to 0.005. The phosphor is in the range of 040 mol, in particular in the range of 0.028 to 0.040 mol, and contains Pb in an amount in the range of 0.00075 to 0.0075 mol with respect to 1 mol of the phosphor. preferable.

  For a light emitting device using a semiconductor in which a voltage is applied to an excitation light source such as a white LED, that is, an SMS phosphor for excitation by light having a wavelength of 350 to 430 nm, the Eu content in 1 mol of the phosphor is 0.0090 to It is in the range of 0.040 mol (that is, x in the composition formula is in the range of 0.0090 to 0.040), and W and / or Pb is 0.00010 to 0 with respect to 1 mol of the phosphor. Contained in an amount in the range of .040 moles.

  The SMS phosphor for excitation with light having a wavelength of 350 to 430 nm has a Eu content in 1 mol of the phosphor in the range of 0.025 to 0.040 mol, particularly in the range of 0.028 to 0.040 mol, It is a phosphor containing W in an amount in the range of 0.00075 to 0.0075 mol with respect to 1 mol of the phosphor, or the Eu content in 1 mol of the phosphor is 0.025 to 0.040 mol The phosphor is preferably in the range of 0.028 to 0.040 mol, and containing Pb in an amount in the range of 0.00075 to 0.0075 mol with respect to 1 mol of the phosphor.

  The above-mentioned SMS phosphor is manufactured by mixing Sr source powder, Mg source powder, Si source powder, Eu source powder, and W source powder and / or Pb source powder, and firing the obtained powder mixture. Can do.

  Each raw material powder of Sr source powder, Mg source powder, Si source powder, Eu source powder, W source powder and Pb source powder may be an oxide powder, hydroxide, halide, carbonate ( (Including basic carbonates), nitrates, oxalates and the like, powders of compounds that generate oxides by heating. The raw material powders may be used alone or in combination of two or more. Each raw material powder preferably has a purity of 99% by mass or more.

  The blending ratio of the Sr source powder, Mg source powder, Si source powder and Eu source powder is the ratio at which the SMS phosphor is generated. Generally, when the total amount of Sr and Eu in the powder mixture is 3 mol The ratio is such that Mg is in the range of 0.9 to 1.1 mol and Si is in the range of 1.9 to 2.1 mol.

  A flux may be added to the powder mixture. The flux is preferably a halide, and particularly preferably a chlorine compound. As a flux, it is preferable to use a chlorine compound powder as a part of the raw material powder. In particular, it is preferable to use a strontium chlorine compound powder. The amount of flux added is preferably such that the total amount of strontium and europium in the powder mixture is 3 mol, and the halogen amount is in the range of 0.0001 to 0.5 mol, preferably 0.02 to 0.00. It is particularly preferable that the amount be in the range of 5 mol.

  Either a dry mixing method or a wet mixing method can be adopted as a method for mixing the raw material powders. When the raw material powder is mixed by a wet mixing method, a rotating ball mill, a vibrating ball mill, a planetary mill, a paint shaker, a rocking mill, a rocking mixer, a bead mill, a stirrer, or the like can be used. As the solvent, water, lower alcohols such as ethanol and isopropyl alcohol can be used.

  The powder mixture is fired in an atmosphere of a reducing gas composed of 0.5 to 5.0% by volume of hydrogen and 99.5 to 95.0% by volume of an inert gas. Examples of inert gases include argon and nitrogen. The firing temperature is generally in the range of 900-1300 ° C. The firing time is generally in the range of 0.5 to 100 hours.

  In the case of using a powder of a compound that generates an oxide by heating as the raw material powder, before firing in a reducing gas atmosphere, the powder mixture is placed in an air atmosphere at a temperature of 600 to 850 ° C. at a temperature of 0.5 to It is preferable to calcine for 100 hours.

  The SMS phosphor obtained by firing may be subjected to classification treatment, acid cleaning treatment with a mineral acid such as hydrochloric acid or nitric acid, and baking treatment as necessary.

  Next, the light emitting device of the present invention will be described with reference to FIGS.

FIG. 1 is a perspective view of an example of an AC type PDP according to the present invention. The AC type PDP is a light emitting device that uses Xe gas with an excitation light source under discharge and uses vacuum ultraviolet light including light emission with a wavelength of 172 nm as excitation light.
In FIG. 1, the plasma display panel includes a front plate 20 and a back plate 30 which are arranged to face each other via a discharge space 10 filled with a discharge gas containing Xe gas. As the discharge gas filled in the discharge space 10, a mixed gas of Xe gas and Ne gas is usually used. The concentration of the Xe gas in the mixed gas is a concentration at which molecular beam emission occurs due to the discharge of the Xe gas, and is generally in the range of 10 to 30% by volume, preferably in the range of 15 to 25% by volume.

  The front plate 20 includes a transparent glass substrate 21, a discharge electrode 25 comprising two column electrodes 24a and 24b formed on the surface of the transparent glass substrate 21 on the back plate side, a dielectric layer 26 covering the discharge electrode, and a dielectric It consists of a dielectric protective layer 27 formed on the surface of the layer. The two column electrodes 24 a and 24 b constituting the discharge electrode 25 are each composed of a transparent electrode 22 and a bus electrode 23. The transparent electrode 22 is generally made of a conductive metal oxide film such as an ITO (indium tin oxide) film or a tin oxide film. The dielectric layer 26 is made of low-melting glass. The dielectric protective layer 27 is made of a magnesium oxide film.

  The back plate 30 includes a transparent glass substrate 31, an address electrode 32 formed on the surface of the transparent glass substrate 31 on the front plate side, a dielectric layer 33 that covers the address electrode 32, and a surface on the surface of the dielectric layer 33. The barrier ribs 34 are formed in stripes, and include a blue light emitting phosphor 35B, a green light emitting phosphor 35G, and a red light emitting phosphor 35R filled between the barrier ribs 34. The address electrode 32 is generally composed of a single phase metal film such as aluminum, copper and silver, or a laminated metal film such as chromium / copper / chromium. The dielectric layer 33 and the partition wall 34 are made of low melting point glass. The blue light emitting phosphor 35B is made of an SMS phosphor for vacuum ultraviolet light in which the excitation light includes light having a wavelength of 172 nm.

  In the AC type PDP of FIG. 1, when a voltage is applied to the discharge electrode 25 of the front plate 20, the Xe gas in the discharge space 10 is discharged to generate vacuum ultraviolet light having a wavelength of 146 nm and a wavelength of 172 nm. Irradiates the SMS phosphor 35B, the green light emitting phosphor 35G, and the red light emitting phosphor 35R provided on the back plate 30 to excite those phosphors, and to produce visible light of the three primary colors of blue, green, and red. Light is emitted, and an image is formed by a combination of these.

FIG. 2 is a cross-sectional view of an example CCFL according to the present invention. The CCFL is a light emitting device that uses Hg gas with an excitation light source under discharge and uses ultraviolet light including light emission with a wavelength of 254 nm as excitation light.
In FIG. 2, CCFL is a glass tube 41 that is a glass member, a discharge gas filled in the internal space 42 of the glass tube 41, a phosphor layer 43 formed on the inner wall surface of the glass tube 41, and the longitudinal direction of the glass tube 41. It consists of a pair of electrodes 44a, 44b provided at both ends, and conductive lines 45a, 45b for electrically connecting the electrodes 44a, 44b and an external power source (not shown). As the discharge gas, a mixed gas of Hg gas and rare gas (for example, Ar gas) is generally used. The phosphor layer 43 includes an SMS phosphor for ultraviolet light in which the excitation light includes light having a wavelength of 254 nm, a green light-emitting phosphor, and a red light-emitting phosphor.

  In the CCFL of FIG. 2, when a high voltage is applied between the electrodes 44 a and 44 b, ultraviolet light having a wavelength of 254 nm is generated by the discharge of the Hg gas filled in the internal space 42, and this ultraviolet light is applied to the phosphor layer 43. Irradiation is performed to excite the phosphors of each color to emit blue, green and red visible light, and white color is generated by mixing the emitted light.

FIG. 3 is a cross-sectional view of an example of a white LED according to the present invention. In the present invention, the white LED is a light emitting device in which excitation light is a semiconductor to which a voltage is applied, and light having a peak in a wavelength range of 350 to 430 nm generated by the semiconductor is used as excitation light.
In FIG. 3, a white LED includes a substrate 51, a semiconductor 53 fixed on the substrate 51 with an adhesive 52, a pair of electrodes 54a and 54b formed on the substrate, a semiconductor 53 and electrodes 54a and 54b. Electrically connected lead wires 55a and 55b, a resin layer 56 covering the semiconductor 53, a phosphor layer 57 provided on the resin layer 56, and a light reflecting material covering the periphery of the resin layer 56 and the phosphor layer 57 58, and conductive lines 59a and 59b for electrically connecting the electrodes 54a and 54b and an external power source (not shown). As an example of the semiconductor 53, an AlGaN-based semiconductor can be given. Examples of the material of the resin layer 56 include a silicone resin. The phosphor layer 57 is a layer in which the SMS phosphor for excitation by light having a wavelength of 350 to 430 nm, a green light emitting phosphor, and a red light emitting phosphor are dispersed in a transparent resin such as glass or silicone resin. be able to.

  In the white LED of FIG. 3, when a voltage is applied to the electrodes 54a and 54b, light having a peak in the wavelength range of 350 to 430 nm is generated from the semiconductor 53, and this light irradiates the phosphor layer 57. Is excited to emit visible light of blue, green and red, and white color is generated by mixing the emitted light.

[Example 1]
SrCO ₃ powder (purity: 99.99 mass%, average particle diameter 2.73Myuemu), basic MgCO ₃ powder _{(4MgCO 3 · Mg (OH)} 2 · 4H 2 O powder, 99.99 wt% purity, mean particle size 11 .08 μm), SiO ₂ powder (purity 99.9% by mass, average particle size 3.87 μm), Eu ₂ O ₃ powder (purity 99.9% by mass, average particle size 2.71 μm), WO ₃ powder (purity 99). Each raw material powder of 0.9 mass% and an average particle diameter of 7 μm is adjusted to have a molar ratio of Sr: Mg: Si: Eu: W of 2.985: 1: 2.000: 0.015: 0.0010. Weighed out. The average particle diameter of each raw material powder is a value measured by a laser diffraction scattering method.

  Each raw material powder weighed was put into a ball mill together with 750 mL of pure water, wet-mixed for 24 hours, and then water was removed by heating to obtain a powder mixture. The obtained powder mixture was put in an alumina crucible, calcined at a temperature of 800 ° C. for 3 hours in an air atmosphere, and then allowed to cool to room temperature, and then in a mixed gas atmosphere of 2 volume% hydrogen-98 volume% argon. The powder was fired at a temperature of 1200 ° C. for 3 hours to obtain a powder fired product. The obtained powder fired product was sieved wet with a sieve made of polyamide having an opening of 20 μm to remove coarse particles, and then dried. As described above, an SMS phosphor containing 0.015 mol of Eu and 0.0010 mol of W with respect to 1 mol of the phosphor was manufactured.

[Example 2]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: W was 2.985: 1: 2.000: 0.015: 0.0050, the same as in Example 1. Thus, an SMS phosphor containing 0.015 mol of Eu and 0.0050 mol of W with respect to 1 mol of the phosphor was manufactured.

[Comparative Example 1]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: W was 2.985: 1: 2.000: 0.015: 0, An SMS phosphor containing 0.015 mol Eu and not containing W with respect to 1 mol of the phosphor was produced.

[Example 3]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: W was 2.980: 1: 2.000: 0.020: 0.0010, the same as in Example 1. Thus, an SMS phosphor containing 0.020 mol of Eu and 0.0010 mol of W with respect to 1 mol of the phosphor was manufactured.

[Example 4]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: W was 2.980: 1: 2.000: 0.020: 0.0050, the same as in Example 1. Thus, an SMS phosphor containing 0.020 mol of Eu and 0.0050 mol of W with respect to 1 mol of the phosphor was manufactured.

[Comparative Example 2]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: W was 2.980: 1: 2.000: 0.020: 0, An SMS phosphor containing 0.020 mol of Eu and not containing W with respect to 1 mol of the phosphor was produced.

[Example 5]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: W was 2.970: 1: 2.000: 0.030: 0.0010, the same as in Example 1. Thus, an SMS phosphor containing 0.030 mol of Eu and 0.0010 mol of W with respect to 1 mol of the phosphor was manufactured.

[Example 6]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: W was 2.970: 1: 2.000: 0.030: 0.0050, the same as in Example 1. Thus, an SMS phosphor containing 0.030 mol of Eu and 0.0050 mol of W with respect to 1 mol of the phosphor was manufactured.

[Comparative Example 3]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: W was 2.970: 1: 2.000: 0.030: 0, An SMS phosphor containing 0.030 mol of Eu and not containing W with respect to 1 mol of the phosphor was produced.

[Example 7]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: W was 2.965: 1: 2.000: 0.035: 0.0010, the same as in Example 1. Thus, an SMS phosphor containing 0.035 mol of Eu and 0.0010 mol of W with respect to 1 mol of the phosphor was manufactured.

[Example 8]
Each raw material powder has a molar ratio of Sr: Mg: Si: Eu: W of 2.965: 1: 2.000: 0.
. 035: An SMS phosphor containing 0.035 mol of Eu and 0.0050 mol of W with respect to 1 mol of the phosphor was manufactured in the same manner as in Example 1 except that the weight was adjusted to 0.0050. did.

[Comparative Example 4]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: W was 2.965: 1: 2.000: 0.035: 0, An SMS phosphor containing 0.035 mol of Eu and 1 wt.% Of phosphor was prepared.

[Evaluation]
The SMS phosphors manufactured in Examples 1 to 8 and Comparative Examples 1 to 4 and the commercially available BAM phosphors were put in an alumina crucible and heat-treated at 500 ° C. for 1 hour in an air atmosphere, and then released to room temperature. Chilled. Each phosphor after being allowed to cool was irradiated with light having a wavelength of 146 nm, a wavelength of 172 nm, a wavelength of 254 nm, and a wavelength of 405 nm to excite the phosphor, and the emission luminance of blue light emitted from the phosphor was measured. Excimer lamps for each wavelength were used as light sources having a wavelength of 146 nm and a wavelength of 172 nm, respectively. A xenon lamp was used as a light source having a wavelength of 254 nm and a wavelength of 405 nm, and the light was split into light having a wavelength of 254 nm and a wavelength of 405 nm using a spectroscope. Table 1 shows the measurement results of the emission luminance. The emission luminance is a relative value with the emission intensity of a commercially available BAM phosphor as 100.

Table 1
────────────────────────────────────────
The amount of Eu and W in 1 mol of phosphor. Luminance when excited with light of each wavelength.
─────────────── ───────────────────
Eu amount (mole) W amount (mole) 146 nm 172 nm 254 nm 405 nm
────────────────────────────────────────
Example 1 0.015 0.0010 73 85 91 160
Example 2 0.015 0.0050 74 90 92 170
────────────────────────────────────────
Comparative Example 1 0.015 0 61 83 89 155
────────────────────────────────────────
Example 3 0.020 0.0010 54 89 106 165
Example 4 0.020 0.0050 60 89 112 170
────────────────────────────────────────
Comparative Example 2 0.020 0 30 82 102 160
────────────────────────────────────────
Example 5 0.030 0.0010 31 74 118 195
Example 6 0.030 0.0050 49 73 119 180
────────────────────────────────────────
Comparative Example 3 0.030 0 25 73 109 168
────────────────────────────────────────
Example 7 0.035 0.0010 23 71 120 180
Example 8 0.035 0.0050 24 72 121 170
────────────────────────────────────────
Comparative Example 4 0.035 0 22 70 114 165
────────────────────────────────────────

  From the results of Table 1, the SMS phosphors containing W in Examples 1 to 4 have higher emission luminance due to excitation of vacuum ultraviolet light having a wavelength of 172 nm than the SMS phosphor containing no W (Comparative Example 1). . In addition, it is known that the SMS phosphor has less decrease in emission luminance over time than the BAM phosphor. Therefore, the SMS phosphor containing W of Examples 1 to 4 is particularly useful for a blue light source of a light emitting device using Xe gas under discharge as an excitation light source. In addition, the SMS phosphors containing W of Examples 5 to 8 have higher emission luminance due to excitation of ultraviolet light having a wavelength of 254 nm than the SMS phosphor containing no W (Comparative Example 4). Therefore, the SMS phosphor containing W of Examples 5 to 8 is particularly useful for a blue light source of a light emitting device using Hg gas under discharge as an excitation light source. In addition, the SMS phosphor containing W in Examples 1 and 3 was compared with the SMS phosphor containing no W (Comparative Example 4), although the amount of Eu as an activation component of the SMS phosphor was small. The emission luminance by excitation of light with a wavelength of 405 nm is equivalent, and the SMS phosphors containing W in Examples 2 and 4 to 8 are all compared with the SMS phosphor containing no W (Comparative Example 4). The emission luminance due to excitation of light having a wavelength of 405 nm is high. Therefore, in the SMS phosphors containing W of Examples 1 to 8, the blue color of the light emitting device using a semiconductor that exhibits light emission having a peak in the wavelength range of 350 to 430 nm when a voltage is applied to the excitation light source. Useful as a luminescence source.

[Example 9]
SrCO ₃ powder (purity: 99.99 mass%, average particle diameter 2.73Myuemu), basic MgCO ₃ powder _{(4MgCO 3 · Mg (OH)} 2 · 4H 2 O powder, 99.99 wt% purity, mean particle size 11 .08 μm), SiO ₂ powder (purity 99.9% by mass, average particle size 3.87 μm), Eu ₂ O ₃ powder (purity 99.9% by mass, average particle size 2.71 μm), PbCl ₂ powder (purity 98). (Mass%, average particle diameter 30 μm) Each raw material powder is weighed so that the molar ratio of Sr: Mg: Si: Eu: Pb is 2.990: 1: 2.000: 0.010: 0.0010. did. The average particle diameter of each raw material powder is a value measured by a laser diffraction scattering method.

  Each raw material powder weighed was put into a ball mill together with 750 mL of pure water, wet-mixed for 24 hours, and then water was removed by heating to obtain a powder mixture. The obtained powder mixture was put in an alumina crucible, calcined at 800 ° C. for 3 hours in an air atmosphere, then allowed to cool to room temperature, and then 1200 ° C. in a mixed gas atmosphere of 2 vol% hydrogen-98 vol% argon. The powder was fired at a temperature of 3 ° C. for 3 hours to obtain a powder fired product. The obtained powder fired product was sieved wet with a sieve made of polyamide having an opening of 20 μm to remove coarse particles, and then dried. As described above, an SMS phosphor containing 0.010 mol Eu and 0.0010 mol Pb with respect to 1 mol of the phosphor was manufactured.

[Example 10]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: Pb was 2.990: 1: 2.000: 0.010: 0.0050, it was the same as Example 9. Thus, an SMS phosphor containing 0.010 mol Eu and 0.0050 mol Pb with respect to 1 mol of the phosphor was manufactured.

[Example 11]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: Pb was 2.990: 1: 2.000: 0.010: 0.0100, the same as in Example 9 Thus, an SMS phosphor containing 0.010 mol of Eu and 0.0100 mol of Pb with respect to 1 mol of the phosphor was manufactured.

[Example 12]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: Pb was 2.990: 1: 2.000: 0.010: 0.0300, the same as in Example 9 Thus, an SMS phosphor containing 0.010 mol of Eu and 0.0300 mol of Pb with respect to 1 mol of the phosphor was manufactured.

[Comparative Example 5]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: Pb was 2.990: 1: 2.000: 0.010: 0, An SMS phosphor containing 0.010 mol of Eu and not containing Pb with respect to 1 mol of the phosphor was produced.

[Example 13]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: Pb was 2.985: 1: 2.000: 0.015: 0.0010, it was the same as Example 9. Thus, an SMS phosphor containing 0.015 mol of Eu and 0.0010 mol of Pb with respect to 1 mol of the phosphor was manufactured.

[Example 14]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: Pb was 2.985: 1: 2.000: 0.015: 0.0050, it was the same as Example 9. Thus, an SMS phosphor containing 0.015 mol Eu and 0.0050 mol Pb with respect to 1 mol of the phosphor was manufactured.

[Comparative Example 6]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: Pb was 2.985: 1: 2.000: 0.015: 0, An SMS phosphor containing 0.015 mol of Eu and not containing Pb with respect to 1 mol of the phosphor was produced.

[Example 15]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: Pb was 2.980: 1: 2.000: 0.020: 0.0010, the same as in Example 9. Thus, an SMS phosphor containing 0.020 mol of Eu and 0.0010 mol of Pb with respect to 1 mol of the phosphor was manufactured.

[Example 16]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: Pb was 2.980: 1: 2.000: 0.020: 0.0050, it was the same as Example 9. Thus, an SMS phosphor containing 0.020 mol of Eu and 0.0050 mol of Pb with respect to 1 mol of the phosphor was manufactured.

[Example 17]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: Pb was 2.980: 1: 2.000: 0.020: 0.0100, the same as in Example 9 Thus, an SMS phosphor containing 0.020 mol of Eu and 0.0100 mol of Pb with respect to 1 mol of the phosphor was manufactured.

[Example 18]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: Pb was 2.980: 1: 2.000: 0.020: 0.0300, the same as in Example 9 Thus, an SMS phosphor containing 0.020 mol of Eu and 0.0300 mol of Pb with respect to 1 mol of the phosphor was manufactured.

[Comparative Example 7]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: Pb was 2.980: 1: 2.000: 0.020: 0, An SMS phosphor containing 0.020 mol of Eu and not containing Pb with respect to 1 mol of the phosphor was produced.

[Example 19]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: Pb was 2.970: 1: 2.000: 0.030: 0.0010, it was the same as in Example 9. Thus, an SMS phosphor containing 0.030 mol of Eu and 0.0010 mol of Pb with respect to 1 mol of the phosphor was manufactured.

[Example 20]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: Pb was 2.970: 1: 2.000: 0.030: 0.0050, the same as Example 9 was performed. Thus, an SMS phosphor containing 0.030 mol of Eu and 0.0050 mol of Pb with respect to 1 mol of the phosphor was manufactured.

[Comparative Example 8]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: Pb was 2.970: 1: 2.000: 0.030: 0, An SMS phosphor containing 0.030 mol of Eu and not containing Pb with respect to 1 mol of the phosphor was produced.

[Example 21]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: Pb was 2.965: 1: 2.000: 0.035: 0.0010, the same as in Example 9. Thus, an SMS phosphor containing 0.035 mol Eu and 0.0010 mol Pb with respect to 1 mol of the phosphor was manufactured.

[Example 22]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: Pb was 2.965: 1: 2.000: 0.035: 0.0050, the same as in Example 9 Thus, an SMS phosphor containing 0.035 mol of Eu and 0.0050 mol of Pb with respect to 1 mol of the phosphor was manufactured.

[Comparative Example 9]
Except that each raw material powder was weighed so that the molar ratio of Sr: Mg: Si: Eu: Pb was 2.965: 1: 2.000: 0.035: 0, An SMS phosphor containing 0.035 mol Eu and not containing Pb with respect to 1 mol of the phosphor was produced.

[Evaluation]
The SMS phosphors produced in Examples 9 to 22 and Comparative Examples 5 to 9 and the commercially available BAM phosphors were put in an alumina crucible and heat-treated at 500 ° C. for 1 hour in an air atmosphere, and then released to room temperature. Chilled. Each phosphor after being allowed to cool was irradiated with light having a wavelength of 146 nm, a wavelength of 172 nm, a wavelength of 254 nm, and a wavelength of 405 nm to excite the phosphor, and the emission luminance of blue light emitted from the phosphor was measured. The results are shown in Table 2. The emission luminance is a relative value with the emission intensity of a commercially available BAM phosphor as 100.

Table 2
────────────────────────────────────────
The amount of Eu and Pb in 1 mol of phosphor. Luminance when excited by light of each wavelength ───────────────── ─────────── ───────
Eu amount (mole) Pb amount (mole) 146 nm 172 nm 254 nm 405 nm
────────────────────────────────────────
Example 9 0.010 0.0010 78 81 80 150
Example 10 0.010 0.0050 77 90 92 155
Example 11 0.010 0.0100 65 92 84 160
Example 12 0.010 0.0300 74 86 86 162
────────────────────────────────────────
Comparative Example 5 0.010 0 71 81 76 148
────────────────────────────────────────
Example 13 0.015 0.0010 65 85 89 158
Example 14 0.015 0.0050 67 87 95 165
────────────────────────────────────────
Comparative Example 6 0.015 0 61 83 89 162
────────────────────────────────────────
Example 15 0.020 0.0010 55 87 105 162
Example 16 0.020 0.0050 53 88 104 162
Example 17 0.020 0.0100 54 91 110 165
Example 18 0.020 0.0300 54 96 108 170
────────────────────────────────────────
Comparative Example 7 0.020 0 30 82 102 160
────────────────────────────────────────
Example 19 0.030 0.0010 30 74 118 175
Example 20 0.030 0.0050 42 75 119 180
────────────────────────────────────────
Comparative Example 8 0.030 0 25 73 109 168
────────────────────────────────────────
Example 21 0.035 0.0010 25 72 120 168
Example 22 0.035 0.0050 27 71 121 172
────────────────────────────────────────
Comparative Example 9 0.035 0 22 70 114 165
────────────────────────────────────────

  From the results in Table 2, the SMS phosphors containing Pb of Examples 9 to 18 have higher emission luminance due to excitation of vacuum ultraviolet light having a wavelength of 172 nm than the SMS phosphors not containing Pb (Comparative Example 6). . In addition, it is known that the SMS phosphor has less decrease in emission luminance over time than the BAM phosphor. Therefore, the SMS phosphor containing Pb of Examples 9 to 18 is particularly useful as a blue light source of a light emitting device that excites the phosphor with vacuum ultraviolet light generated by discharge of Xe gas. In addition, the SMS phosphors containing Pb of Examples 19 to 22 have higher emission luminance due to excitation of ultraviolet light having a wavelength of 254 nm than the SMS phosphors not containing Pb (Comparative Example 9). Therefore, the SMS phosphor containing Pb of Examples 19 to 22 is particularly useful for a blue light source of a light emitting device using Hg gas under discharge as an excitation light source. Further, the SMS phosphors containing Pb of Examples 9 to 17 were compared with the SMS phosphor containing no Pb (Comparative Example 8), although the amount of Eu as an activation component of the SMS phosphor was small. The emission luminance by excitation of light having a wavelength of 405 nm is equivalent, and the SMS phosphors containing Pb in Examples 18 to 22 are all compared with the SMS phosphor containing no Pb (Comparative Example 8). Luminance is high due to excitation of 405 nm light. Therefore, the SMS phosphors containing Pb of Examples 9 to 22 are blue light emitting devices using a semiconductor that exhibits light emission having a peak in the wavelength range of 350 to 430 nm when a voltage is applied to the excitation light source. Useful as a luminescence source.

DESCRIPTION OF SYMBOLS 10 Discharge space 20 Front plate 21 Transparent glass substrate 22 Transparent electrode 23 Bus electrode 24a, 24b Column electrode 25 Discharge electrode 26 Dielectric layer 27 Dielectric protective layer 30 Back plate 31 Transparent glass substrate 32 Address electrode 33 Dielectric layer 34 Partition 35B Blue light emitting phosphor 35G Green light emitting phosphor 35R Red light emitting phosphor 41 Glass tube 42 Internal space 43 Phosphor layer 44a, 44b Electrode 45a, 45b Conductive wire 51 Substrate 52 Adhesive material 53 Semiconductor 54a, 54b Electrode 55a, 55b Lead wire 56 Resin layer 57 Phosphor layer 58 Light reflecting material 59a, 59b Conductive wire

Claims (18)

_{Sr 3-x MgSi 2 O 8} : is represented by a composition formula of Eu _x, x is a value in the range of 0.0090 to 0.025, 0 W and / or Pb with respect to 1 mol of the phosphor. A blue light-emitting phosphor for a light-emitting device that contains vacuum ultraviolet light containing light having a wavelength of 172 nm, which is contained in an amount in the range of 00010 to 0.040 mol, as excitation light.   X in the composition formula is a value in the range of 0.010 to 0.025, and W is contained in an amount in the range of 0.00075 to 0.0075 mol per mol of the phosphor. The blue light emitting phosphor described.   The x in the composition formula is a value in the range of 0.0090 to 0.025, and Pb is contained in an amount in the range of 0.00050 to 0.040 mol with respect to 1 mol of the phosphor. The blue light emitting phosphor described. Sr _3−x MgSi ₂ O ₈ : Eux is represented _by the composition formula, and x is a value in the range of 0.025 to 0.040, and W and / or Pb is set to 0.1 with respect to 1 mol of the phosphor. A blue light-emitting phosphor for a light-emitting device containing ultraviolet light containing light having a wavelength of 254 nm as excitation light, contained in an amount in the range of 00010 to 0.0075 mol.   The x in the composition formula is a value in the range of 0.025 to 0.040, and W is contained in an amount in the range of 0.00075 to 0.0075 mol with respect to 1 mol of the phosphor. The blue light emitting phosphor described.   The x in the composition formula is a value in the range of 0.025 to 0.040, and Pb is contained in an amount in the range of 0.00075 to 0.0075 mol with respect to 1 mol of the phosphor. The blue light emitting phosphor described. _{Sr 3-x MgSi 2 O 8} : is represented by a composition formula of Eu _x, x is a value in the range of 0.0090 to 0.040, 0 W and / or Pb with respect to 1 mol of the phosphor. A blue light-emitting phosphor for a light-emitting device containing excitation light as light having a peak in a wavelength range of 350 to 430 nm, contained in an amount in the range of 00010 to 0.040 mol.   The composition formula x is a value in the range of 0.025 to 0.040, and W is contained in an amount in the range of 0.00075 to 0.0075 mol with respect to 1 mol of the phosphor. The blue light emitting phosphor described.   X in the composition formula is a value in the range of 0.025 to 0.040, and Pb is contained in an amount in the range of 0.00075 to 0.0075 mol with respect to 1 mol of the phosphor. The blue light emitting phosphor described. A light emitting device comprising: an excitation light source that emits vacuum ultraviolet light including light having a wavelength of 172 nm; and a phosphor that emits blue light when excited by vacuum ultraviolet light from the excitation light source. _{, Sr 3-x MgSi 2 O} 8: is represented by a composition formula of Eu _x, x is a value in the range of 0.0090 to 0.025, the W and / or Pb with respect to 1 mol of the phosphor 0 A light-emitting device which is a phosphor containing 0.00000 to 0.040 mol in an amount.   The excitation light source is Xe gas under discharge, x in the composition formula of the phosphor is a value in the range of 0.010 to 0.025, and the phosphor has W for 1 mol of the phosphor. The light-emitting device according to claim 10, wherein the phosphor is contained in an amount in the range of 0.00075 to 0.0075 mol.   The excitation light source is Xe gas under discharge, x in the composition formula of the phosphor is a value in the range of 0.0090 to 0.025, and the phosphor has Pb with respect to 1 mol of the phosphor. The light emitting device according to claim 10, wherein the light emitting device is a phosphor contained in an amount in the range of 0.00050 to 0.040 mol. A light-emitting device including an excitation light source that emits ultraviolet light including light having a wavelength of 254 nm and a phosphor that emits blue light when excited by ultraviolet light from the excitation light source. _3-x MgSi ₂ O ₈ : Eux is represented _by the composition formula, x is a value in the range of 0.025 to 0.040, and W and / or Pb is 0.00010 with respect to 1 mol of the phosphor. A light emitting device which is a phosphor containing in an amount in the range of ˜0.0075 mol.   The excitation light source is Hg gas under discharge, x in the composition formula of the phosphor is a value in the range of 0.025 to 0.040, and the phosphor has W for 1 mol of the phosphor. The light-emitting device according to claim 13, wherein the light-emitting device is a phosphor contained in an amount ranging from 0.00075 to 0.0075 mol.   The excitation light source is Hg gas under discharge, x in the composition formula of the phosphor is a value in the range of 0.025 to 0.040, and the phosphor has Pb with respect to 1 mol of the phosphor. The light-emitting device according to claim 13, wherein the light-emitting device is a phosphor contained in an amount ranging from 0.00075 to 0.0075 mol. A light emitting device comprising: an excitation light source that emits light having a peak in a wavelength range of 350 to 430 nm; and a phosphor that emits blue light when excited by light from the excitation light source. _{, Sr 3-x MgSi 2 O} 8: is represented by a composition formula of Eu _x, x is a value in the range of 0.0090 to 0.040, the W and / or Pb with respect to 1 mol of the phosphor 0 A light-emitting device which is a phosphor containing 0.00000 to 0.040 mol in an amount.   The excitation light source is a semiconductor to which a voltage is applied, x in the composition formula of the phosphor is a value in the range of 0.025 to 0.040, and the phosphor has W for 1 mol of the phosphor. The light-emitting device according to claim 16, wherein the light-emitting device is a phosphor contained in an amount ranging from 0.00075 to 0.0075 mol.   The excitation light source is a semiconductor to which a voltage is applied, x in the composition formula of the phosphor is a value in the range of 0.025 to 0.040, and the phosphor has Pb with respect to 1 mol of the phosphor. The light-emitting device according to claim 16, wherein the light-emitting device is a phosphor contained in an amount ranging from 0.00075 to 0.0075 mol.

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