JP4982812B2 - Phosphor for vacuum ultraviolet light excitation - Google Patents

Description

  The present invention relates to a phosphor for vacuum ultraviolet light excitation.

  In recent years, with the environmental regulations, there is an increasing demand for fluorescent lamps that do not use mercury. As a fluorescent lamp that does not use mercury, a fluorescent lamp that is excited by ultraviolet rays in the vacuum ultraviolet region having a wavelength of 172 nm obtained using xenon is known. However, since conventional phosphors are optimized so that they can be excited by ultraviolet rays having a mercury ray wavelength (254 nm), a phosphor suitable for xenon excitation is required.

  Since the vacuum ultraviolet light with a wavelength of 172 nm is light with higher energy than the absorption edge of the host crystal, the direct excitation mechanism in which the emitted ions are excited directly by ultraviolet rays and visible fluorescence is generated as in the case of excitation with mercury rays. Rather, visible fluorescence needs to be generated by an indirect excitation mechanism in which the energy absorbed by the matrix moves to the emission center, but there are not many crystals in which indirect excitation occurs efficiently.

Currently used phosphors for xenon excitation include BaMgAl ₁₀ O ₁₇ : Eu that emits blue light, LaPO ₄ that emits green light: Tb, Ce, Zn ₂ SiO ₄ : Mn, (Y, Gd) BO ₃ : Tb, (Y, Gd) BO ₃ : Eu, Y (P, V) O ₄ : Eu, etc. that emit red light. However, these phosphors have a drawback that they are easily deteriorated because the host material is excited at a wavelength that absorbs light. For this reason, for example, a stable phosphor using silica or the like as a base material is required.

  As a method therefor, a method (Patent Document 1) for performing an improvement such as coating the phosphor surface has been performed. In addition, many other phosphors having a new composition using silica-based crystals (Patent Documents 2 and 3) and aluminate crystals (Patent Documents 4 and 5) have been developed, but there are many new phosphors. Has not been found.

In addition to mercury-free fluorescent lamps, plasma display devices can be cited as devices that excite phosphors with xenon emission lines. The plasma display uses Xe's 147 nm emission line, and phosphors include Zn ₂ SiO ₄ : Mn (green), (Y, Gd) BO ₃ : Eu (red), BaMgAl ₁₀ O ₁₇ : Eu (Blue) etc. are used. In a plasma display, chromaticity (X and Y values in CIE coordinates) and saturation are important. Originally, a phosphor derived from a rare earth ff transition exhibiting a sharp emission peak is desirable, but there is no phosphor exhibiting appropriate color purity, and there is no phosphor capable of obtaining sufficient fluorescence intensity. BaMgAl ₁₀ O ₁₇ : Eu using fd transition, Zn ₂ SiO ₄ : Mn using dd transition, or the like is used.

  Another problem is that a circuit for converting the drive voltage is required because the three R, G, and B colors used in the matrix composition are different. Red (R) and Green (G) The blue (B) phosphor matrix preferably has a similar dielectric constant.

It is considered that the above problem can be solved if a phosphor of R, G, B in which a rare earth emission center is fixed in stable amorphous silica is obtained. As a phosphor using amorphous silica, an example as in Patent Document 6 has been reported, but light emission in the vacuum ultraviolet region has not been reported. In addition, a phosphor produced by introducing a metal, a rare earth element, or the like into a porous glass based on silica and firing the phosphor exhibits a relatively strong fluorescence intensity in the vacuum ultraviolet region (Patent Documents 7 and 8). Non-Patent Document 1), and the fact that a light emission phenomenon is observed in many rare earth metals in a powder obtained by sintering porous silica powder (Non-Patent Documents 2 and 3) has also been reported. However, these phosphors are not practical enough because the fluorescence intensity by vacuum ultraviolet light excitation is as low as about 10% to 20% compared to commercially available phosphors.
JP2002-38148 JP2005-60670 JP2003-213254 JP2004-197044 JP2005-60679 JP2003-155478 JP2005-142037 JP2005-060679 Chemistry Letters 86 (23): 231908 (2005) Proceedings of the 67th Annual Conference of the Japan Society of Applied Physics, p.1323 19th Autumn Symposium Abstracts, p.79

  The main object of the present invention is a phosphor excited by ultraviolet light in the vacuum ultraviolet region, which can be used stably over a long period of time, has a high emission intensity, and can exhibit a suitable chromaticity. It is to provide a phosphor for ultraviolet light excitation.

  The present inventor has intensively studied to achieve the above-described object. As a result, porous silica is used as a base material, and it is doped with a light-emitting element composed of a rare earth element and a sensitizer composed of at least one alkali metal element selected from the group consisting of Li, Na, K, Rb and Cs. Then, according to the firing method, it has been found that a phosphor for vacuum ultraviolet light excitation that can achieve the above-described object can be obtained, and the present invention has been completed here.

That is, the present invention provides the following phosphor for vacuum ultraviolet light excitation.
1. Vacuum ultraviolet light excitation obtained by doping porous silica with a rare earth element that exhibits fluorescence by ff transition and at least one alkali metal element selected from the group consisting of Li, Na, K, Rb, and Cs, followed by firing Phosphor.
2. Porous silica, a SiO ₂ contained more than 95 wt%, the pore diameter is 1 nm to 10 nm, fluorescence vacuum ultraviolet excitation according specific surface area to item 1, which is a porous body of 100m ² / g~800m ² / g body.
3. Item 3. The phosphor for vacuum ultraviolet light excitation according to Item 1 or 2, wherein the rare earth element is at least one selected from the group consisting of Tb, Eu, Sm, Tm, and Dy.
4). The content of the rare earth element is 0.01 to 12% by weight, the content of at least one alkali metal element selected from the group consisting of Li, Na, K, Rb and Cs is 0.01 to 9% by weight, The phosphor for vacuum ultraviolet light excitation according to any one of the above items 1 to 3, wherein the content of is 0.4% by weight or less, the content of Na is 1% by weight or less, and the content of K is 3% by weight or less.
5. Item 5. The phosphor for vacuum ultraviolet light excitation according to any one of Items 1 to 4, wherein the content of the alkali metal element is 0.6 to 1.6 mol with respect to 1 mol of the rare earth element.
6). The porous ultraviolet light excitation according to any one of the above items 1 to 5, obtained by further calcination after doping porous silica with at least one element selected from the group consisting of Ba, Er, In and Gd Phosphor.
7). 0.01 to 12% by weight of Tb, 0.01 to 9% by weight of at least one alkali metal selected from the group consisting of Li, Na, K, Rb, and Cs, and 0.4% by weight or less of Li and 1% of Na Item 6. The phosphor for vacuum ultraviolet light excitation according to any one of Items 1 to 5, which is a phosphor emitting green light containing not more than wt% and not more than 3 wt% of K.
8). 0.01 to 12% by weight of at least one element selected from the group consisting of Eu and Sm, and 0.01 to 9% by weight of at least one alkali metal selected from the group consisting of Li, Na, K, Rb and Cs The phosphor for vacuum ultraviolet light excitation according to any one of the above items 1 to 5, which is a phosphor emitting red light containing 0.4% by weight or less of Li, 1% by weight or less of Na, and 3% by weight or less of K. .
9. 0.01 to 12% by weight of Tm, 0.01 to 9% by weight of at least one alkali metal selected from the group consisting of Li, Na, K, Rb and Cs, wherein Li is 0.4% by weight or less, and Na is 1%. Item 6. The phosphor for vacuum ultraviolet light excitation according to any one of Items 1 to 5, which is a phosphor emitting blue light containing not more than% by weight and not more than 3% by weight of K.
10. 0.01 to 12% by weight of Tb, 0.01 to 9% by weight of at least one alkali metal selected from the group consisting of Li, Na, K, Rb and Cs, with Li of 0.4% by weight or less and Na of 1 Item 7. The phosphor for vacuum ultraviolet light excitation according to Item 6, which is a phosphor that emits green light and contains 0.01% to 9% by weight of Gd and 0.01 to 9% by weight of Gd or less, K is 3% by weight or less.
11. 0.01% to 12% by weight of at least one element selected from the group consisting of Eu and Sm, and 0.01% to 9% by weight of at least one alkali metal selected from the group consisting of Li, Na, K, Rb and Cs Item 7. The vacuum ultraviolet ray according to Item 6, which is a phosphor emitting red light containing 0.4% by weight or less of Li, 1% by weight or less of Na, 3% by weight or less of K, and 0.01 to 9% by weight of Gd. Phosphor for photoexcitation.
12 0.01 to 12% by weight of Tm, 0.01 to 9% by weight of at least one alkali metal selected from the group consisting of Li, Na, K, Rb and Cs, with Li of 0.4% by weight or less and Na of 1 Item 7. The vacuum ultraviolet light excitation according to Item 6, wherein the phosphor emits blue light and contains 0.01 to 9% by weight of at least one element selected from the group consisting of Er and In, and less than 10% by weight, K is 3% by weight or less. Phosphor.
13. Tm is 0.02 to 12% by weight, at least one alkali metal selected from the group consisting of Li, Na, K, Rb and Cs is 0.01 to 9% by weight, Li is 0.4% by weight or less, and Na is 1%. Item 7. The phosphor for vacuum ultraviolet light excitation according to Item 6, which is a phosphor that emits blue light and contains 0.01% to 1% by weight of Ba and 0.01 to 1% by weight of K.

  The phosphor for vacuum ultraviolet light excitation of the present invention has amorphous silica as a main component, a specific light emitting element and a sensitizer component fixed thereto, and by irradiating ultraviolet light below the vacuum ultraviolet region, It emits strong fluorescence stably for a long time.

  As for chromaticity, there is an advantage that purer R, G, and B can be obtained as compared with commercially available products.

  Therefore, by using the phosphor of the present invention, for example, an energy-saving, long-life mercury-free fluorescent lamp, a mercury-free CCFL or a liquid crystal display using it as a backlight, a long-life and colorful plasma display product, etc. Can be obtained.

4 is a drawing showing a fluorescence spectrum of a blue phosphor obtained in Example 4. 6 is a drawing showing a fluorescence spectrum of a green phosphor obtained in Example 10. FIG. 4 is a drawing showing a fluorescence spectrum of a red phosphor obtained in Example 13. It is a chromaticity coordinate which shows the chromaticity value of the fluorescent substance of Example 10, 13, 17, 4 and a commercially available fluorescent substance.

  The phosphor for vacuum ultraviolet light excitation according to the present invention is obtained by using porous silica as a base material, doping a rare earth element and a specific sensitizer, and then firing.

  The vacuum ultraviolet excitation phosphor of the present invention will be specifically described below.

Porous silica The porous silica used in the present invention may be a porous body mainly composed of SiO ₂ , and particularly preferably contains 95% by weight or more of SiO ₂ . In the porous silica, as components other than SiO ₂ , elements such as Al and B may be contained depending on the production method.

  The pore shape of the porous silica is preferably continuous pores so that ions can be introduced from the outside to the inside. The pore diameter is preferably about 1 nm to 10 nm, and more preferably about 2 nm to 4 nm. By using porous silica having a pore diameter within this range, a phosphor having good luminance can be obtained. In this case, the pore diameter is a value obtained by the BET method using the nitrogen adsorption method.

  The particle size of the porous silica is not particularly limited, but usually the average particle size is preferably in the range of about 1 μm to 30 μm, more preferably about 3 μm to 20 μm. The average particle size of the porous silica is a value measured by a particle size distribution measuring method using a laser diffraction / scattering method of JIS R 1629-1997 raw material using an optical particle size measuring device.

The specific surface area of porous silica is preferably 100m ² / g~800m ² / g approximately, and more preferably 300m ² / g~600m ² / g approximately. The specific surface area is a value determined by the BET method using the nitrogen adsorption method.

  Further, the presence of metal impurities such as Fe in the porous silica leads to a decrease in luminance. For this reason, the Fe content is desirably 100 ppm or less.

  It does not specifically limit as a method to manufacture porous silica, What is necessary is just the method which can manufacture porous silica which satisfies above-described conditions. For example, it may be a commercially available silica gel production method produced by agglomerating silica colloid, or spinodal phase separation of borosilicate glass into boric acid phase and silica phase and leaching of boric acid phase with acid to obtain porous silica. The method may be used. In particular, the latter method is particularly advantageous in that the pore diameter and surface area can be freely changed.

Luminescent Element In the phosphor of the present invention, a rare earth element that exhibits fluorescence by ff transition is used as the luminescent element. Examples of such rare earth elements include Tb, Eu, Sm, Tm, Dy and the like. From these rare earth elements, an element to be used may be determined according to the target emission color. For example, Tb can be used to obtain a phosphor emitting green light, Eu or Sm can be used to obtain a phosphor emitting red light, and a phosphor emitting blue light can be obtained. Tm can be used.

  The content of the rare earth element in the phosphor for vacuum ultraviolet light excitation of the present invention can be appropriately determined according to the target emission intensity. Usually, the rare earth element content is preferably about 0.01 to 12% by weight, more preferably about 0.5 to 5% by weight, based on the entire phosphor.

  In the phosphor for vacuum ultraviolet light excitation according to the present invention, it is considered that the rare earth element is immobilized in an ionic state using amorphous silica as a base material.

Sensitizer In the phosphor for vacuum ultraviolet light excitation of the present invention, it is necessary to use at least one alkali metal element selected from the group consisting of Li, Na, K, Rb and Cs as the sensitizer. By using these sensitizers together with the rare earth elements described above, the emission intensity can be greatly improved, and a high-luminance luminescent material can be obtained. Among them, Rb and Cs are particularly effective for increasing the emission intensity.

  The content of at least one alkali metal element selected from the group consisting of Li, Na, K, Rb and Cs is preferably about 0.01 to 9% by weight, more preferably about 0.1 to 2% by weight. preferable. However, for each element of Li, Na, and K, even if the amount is within the above range, if the addition amount is too large, the emission intensity may decrease. Therefore, it is preferable that the Li content is about 0.4% by weight or less, the Na content is about 1% by weight or less, and the K content is about 3% by weight or less.

  In addition, when the alkali metal element is used in the range of the above content, about 0.6 to 1.6 mol, more preferably 0.7 to 1.3, with respect to 1 mol of the rare earth element, the emission intensity is greatly improved. be able to.

Other Components In the phosphor for vacuum ultraviolet light excitation according to the present invention, the emission intensity can be further improved by further containing Ba, Er, In, Gd or the like, if necessary.

  The content of Ba, Er, In, Gd, and the like can be appropriately determined according to the target emission intensity, but usually the effect of enhancing the emission intensity in the range of about 0.01 to 9% by weight. Can be obtained.

Production Method of Vacuum Ultraviolet Light Exciting Phosphor To produce the vacuum ultraviolet light excitation phosphor of the present invention, first, porous silica is doped with a light emitting element and a sensitizer.

  There is no particular limitation on the method for doping the luminescent element and the sensitizer, for example, a method of doping the target element by a vapor phase method such as a CVD method, or a porous solution in a solution containing the luminescent element and the sensitizer component. A method of immersing silica can be applied. In particular, the method of immersing in a solution is advantageous in that the element is easily homogeneously doped.

  In the method of immersing porous silica in the solution, the concentration of rare earth elements in the solution to be used is usually preferably about 0.01 mol / L to 6 mol / L, preferably about 0.03 mol / L to 3 mol / L. More preferably. The concentration of at least one alkali metal element selected from the group consisting of Li, Na, K, Rb and Cs is usually preferably about 0.01 mol / L to 6 mol / L, preferably about 0.03 mol / L to about 3 mol / L is more preferable. Further, when doping with Ba, Er, In, Gd or the like, the concentration of these components is preferably about 0.05 to 6 mol / L.

  As a solvent of the solution, water is usually used. As the above-described luminescent element and sensitizer, a compound that is soluble in the solvent to be used may be used. When water is used as a solvent, nitrates, chlorides and the like can be used.

  In the method of immersing porous silica in a solution containing a light emitting element and a sensitizer, the porous silica may be added to the solution, stirred and sufficiently dispersed and allowed to stand. The temperature of the solution may normally be about 0 ° C. to room temperature, and the immersion time may be about 10 minutes to 2 hours.

  Next, by removing the porous silica from the solution and baking it, the intended phosphor for exciting vacuum ultraviolet light can be obtained. The firing temperature is preferably about 850 ° C. to 1250 ° C., more preferably about 1000 to 1100 ° C. If the baking temperature is too low or too high, sufficient fluorescence intensity cannot be obtained, which is not preferable. The firing time may usually be about 2 to 6 hours.

The firing atmosphere is not particularly limited, but for Eu ³⁺ , firing in an oxygen atmosphere that can reduce the amount of Eu ²⁺ that does not contribute to red light emission is particularly desirable.

Phosphor for vacuum ultraviolet light excitation The phosphor for vacuum ultraviolet light excitation obtained by the above-described method is obtained by immobilizing a light emitting element and a sensitizer in amorphous silica.

  The obtained phosphor is excited by irradiation with ultraviolet rays in the vacuum ultraviolet region and emits strong fluorescence.Silica as a base material has high ultraviolet transmittance and can be excited with short-wavelength light. Defects due to ultraviolet irradiation are less likely to occur and can be used stably as a light emitter for a long period of time. Further, the color purity has an advantage that purer red (R), green (G), and blue (B) can be obtained as compared with commercially available products.

  The phosphor for vacuum ultraviolet light excitation of the present invention can be made into a phosphor having a target emission color by selecting the kind of rare earth element. Specific examples of the phosphor having such a specific emission color are as follows.

  As a phosphor for vacuum ultraviolet light excitation that emits green light, Tb is 0.01 to 12% by weight based on the whole phosphor, and at least one alkali metal selected from the group consisting of Li, Na, K, Rb, and Cs Examples include phosphors containing 0.01 to 9% by weight of elements, 0.4% by weight or less of Li, 1% by weight or less of Na, and 3% by weight or less of K.

  As the phosphor for vacuum ultraviolet light excitation that emits red light, 0.01% to 12% by weight of at least one element selected from the group consisting of Eu and Sm, based on the whole phosphor, Li, Na, K, Rb And phosphor containing 0.01 to 9% by weight of at least one alkali metal element selected from the group consisting of Cs, Li of 0.4% by weight or less, Na of 1% by weight or less, and K of 3% by weight or less. It can be illustrated.

  As a phosphor for vacuum ultraviolet light excitation that emits blue light, Tm is 0.01 to 12% by weight based on the whole phosphor, and at least one alkali metal selected from the group consisting of Li, Na, K, Rb and Cs Examples include phosphors containing 0.01 to 9% by weight of elements, 0.4% by weight or less of Li, 1% by weight or less of Na, and 3% by weight or less of K.

  In addition, as a phosphor for vacuum ultraviolet light excitation that emits green light with enhanced emission intensity, the group consisting of 0.01 to 12% by weight of Tb and Li, Na, K, Rb, and Cs on the basis of the whole phosphor. 0.01 to 9% by weight of at least one alkali metal element selected from Li, 0.4% by weight or less of Li, 1% by weight or less of Na, 3% by weight or less of K, and 0.01 to 9% by weight of Gd Examples of phosphors to be used are as follows.

  As a phosphor for vacuum ultraviolet light excitation that emits red light with enhanced emission intensity, 0.01% to 12% by weight of at least one element selected from the group consisting of Eu and Sm, based on the whole phosphor, At least one alkali metal element selected from the group consisting of Li, Na, K, Rb, and Cs is 0.01 to 9 wt%, Li is 0.4 wt% or less, Na is 1 wt% or less, and K is 3 wt%. And phosphors containing 0.01 to 9% by weight of Gd.

  As a phosphor for vacuum ultraviolet light excitation that emits blue light with enhanced emission intensity, Tm is 0.01% to 12% by weight based on the whole phosphor, and a group consisting of Li, Na, K, Rb and Cs. At least one selected alkali metal element is 0.01 to 9% by weight, Li is 0.4% by weight or less, Na is 1% by weight or less, K is 3% by weight or less, and is selected from the group consisting of Er and In. Examples thereof include phosphors containing 0.01 to 9% by weight of at least one element.

  Other examples of phosphors for vacuum ultraviolet light excitation that emit blue light with enhanced emission intensity include 0.02% to 12% by weight of Tm, Li, Na, K, Rb, and Cs, based on the entire phosphor. 0.01 to 9% by weight of at least one alkali metal element selected from the group consisting of Li, 0.4% by weight or less, Na 1% by weight or less, K 3% by weight or less, and Ba 0.01 to 1%. Illustrative examples include phosphors containing wt%.

  The phosphor for vacuum ultraviolet light excitation of the present invention can be effectively used for various applications as a phosphor for vacuum ultraviolet light excitation utilizing the above-described excellent characteristics. For example, it can be used as a phosphor in a lighting device, a display device, a mercury-free fluorescent lamp, a plasma display, and the like, and the fluorescent lamp using the phosphor of the present invention can be used in a liquid crystal display, a copy device, a scanner device, etc. is there.

  Hereinafter, the present invention will be described in more detail with reference to examples.

Examples 1-25 and Comparative Examples 1-8
A borosilicate glass having the composition (% by weight) shown in Table 1 below was melted at 1400 ° C., quenched, and then pulverized to an average particle size of about 8 to 9 μm. Subsequently, it was treated with 1N nitric acid at 90 ° C. for 2 hours, collected by filtration, and washed with water to obtain porous silica.

  The specific surface area, pore diameter and average particle diameter of the obtained porous silica are shown in Table 2 below. The specific surface area and the pore diameter are values obtained by the BET method using a nitrogen adsorption method, and the average particle diameter is a value measured using an optical particle size measuring device. In addition, as a commercially available silica gel, silica gel (NA-300H: symbol F) manufactured by Tosoh Silica Co., Ltd. (CX-200: symbol E) and Nagara Science Co., Ltd. was used.

  Each porous silica obtained by the above-described method was immersed in a solution containing a luminescent element and a sensitizer shown in Tables 3 to 8 at about 20 ° C. for about 1 hour, and then collected by filtration. Tables 3 to 8 Was fired at the temperature shown in FIG. 2 for 2 hours to obtain a phosphor for vacuum ultraviolet light excitation. Tb was fired in air for 6 hours, Tm was fired in a reducing atmosphere for 2 hours, and Eu was fired in an oxygen atmosphere for 2 hours.

  In order to eliminate the non-uniformity of brightness due to the pellet preparation for each vacuum ultraviolet light excitation phosphor obtained by the above method, powder is packed in a cell having a quartz cell glass window, and ultraviolet light is emitted from the quartz glass side. The fluorescence spectrum was measured by irradiation. The fluorescence spectrum was measured under a nitrogen purge using a deuterium lamp (wavelength 160 nm).

  Tables 3 to 8 below show the peak intensity of light emission for each phosphor. The Tb-containing green phosphor has a peak intensity of 543 nm, the Eu-containing red phosphor has a peak intensity of 610 nm, and the Tm-containing blue phosphor has a peak intensity of 458 nm.

  Examples 1 to 6 shown in Table 3 show the fluorescence intensities of blue light emitting phosphors containing Tm as a light emitting element and Cs as a sensitizer. It is clear that the fluorescence intensity is improved as compared with the phosphor of Comparative Example 1 that does not contain Cs.

  Examples 7 to 12 shown in Table 4 show the fluorescence intensities of green-emitting phosphors containing Tb as a luminescent element and Cs or Rb as a sensitizer element. Compared with the phosphor of Comparative Example 2 that does not contain a sensitizer component, an improvement in fluorescence intensity is observed.

  Examples 13 to 16 shown in Table 5 show the fluorescence intensities of red light emitting phosphors containing Eu as a light emitting element and Rb or Cs as a sensitizer element. It is clear that the fluorescence intensity is improved as compared with the phosphor of Comparative Example 3 which does not contain a sensitizer component.

  Examples 17 to 18 shown in Table 6 show the fluorescence intensities of red light-emitting phosphors containing Sm as a luminescent element and Rb or Cs as a sensitizer element. It is clear that the fluorescence intensity is improved as compared with the phosphor of Comparative Example 4 which does not contain a sensitizer component.

  Examples 19 to 25 shown in Table 7 show the fluorescence intensities of green phosphors containing Tb as a luminescent element and Li, Na or K as a sensitizer element. When compared with the phosphor of Comparative Example 5 which does not contain the sensitizer component shown in Table 8, it is clear that the fluorescence intensity is improved. Comparative Examples 6 to 8 are examples in which the amount of Li, Na, or K added is large. When the amount of these components added is excessive, a decrease in fluorescence intensity is observed.

  1 to 3 show fluorescence spectra of the respective phosphors obtained in Example 4, Example 10 and Example 13. FIG.

Further, the green phosphor of Example 10 (luminescent element: Tb ³⁺ ), the red phosphor of Example 13 (luminescent element: Eu ³⁺ ), the red phosphor of Example 17 (issuing element: Sm ³⁺ ), and The x and y coordinates in the CIE chromaticity coordinates of the blue phosphor (luminescent element: Tm ³⁺ ) of Example 4 are x = 0.32, Y = 0.57, x = 0.63, y = 0.36, X = 0.55, Y, respectively. = 0.32, X = 0.152, Y = 0.15.

  FIG. 4 is chromaticity coordinates showing chromaticity values of the phosphors of Examples 10, 13, 17 and 4 and commercially available phosphors. It can be seen that B and G are shifted in the direction that people feel B and G, in particular, compared with those on the market.

Claims (11)

The porous silica, a rare earth element showing fluorescence by ff transition, after doped with at least one alkali metal element selected from the group consisting of Rb and Cs, a vacuum ultraviolet excitation phosphor obtained by firing A phosphor for vacuum ultraviolet light excitation, wherein the rare earth element content is 0.01 to 12% by weight and the content of at least one alkali metal element selected from the group consisting of Rb and Cs is 0.01 to 9% by weight . ^{2. The} fluorescent material for exciting vacuum ultraviolet light according to claim 1, wherein the porous silica is a porous material containing 95% by weight or more of SiO ₂ , a pore diameter of 1 nm to 10 nm, and a specific surface area of 100 m ² / g to 800 m ² / g. body. 2. The phosphor for vacuum ultraviolet light excitation according to claim 1, wherein the rare earth element is at least one selected from the group consisting of Tb, Eu, Sm, Tm and Dy. 2. The phosphor for vacuum ultraviolet light excitation according to claim 1, wherein the phosphor is further obtained by doping porous silica with at least one element selected from the group consisting of Ba, Er, In and Gd, followed by firing. And 0.01 to 12% by weight of Tb, fluorescence vacuum ultraviolet excitation of claim 1 is a phosphor emitting green light having 0.01 to 9 wt% including at least one alkali metal selected from the group consisting of Rb and Cs body. Fluorescence and at least one element of 0.01 to 12 wt%, a red emission having 0.01 to 9 wt% including at least one alkali metal selected from the group consisting of Rb and Cs selected from the group consisting of Eu and Sm 2. The phosphor for vacuum ultraviolet light excitation according to claim 1, wherein the phosphor is a body. And 0.01 to 12% by weight of Tm, for vacuum ultraviolet excitation of claim 1 is a phosphor that emits blue light having at least one 0.01 to 9 wt% containing an alkali metal selected from the group consisting of Rb and Cs Phosphor. And 0.01 to 12% by weight of Tb, claims and 0.01 to 9 wt% of at least one alkali metal selected from the group consisting of Rb and Cs, a phosphor emitting green light containing Gd 0.01 to 9 wt% 4. The phosphor for vacuum ultraviolet light excitation according to 4 . At least the one element and 0.01% to 12% by weight selected from the group consisting of Eu and Sm, and 0.01 to 9 wt% of at least one alkali metal selected from the group consisting of Rb and Cs, 0.01 to the Gd The phosphor for vacuum ultraviolet light excitation according to claim 4 , which is a phosphor that emits red light and contains 9% by weight. 0.01 to 12% by weight of Tm, 0.01 to 9% by weight of at least one alkali metal selected from the group consisting of Rb and Cs , and 0.01 to 9 % of at least one element selected from the group consisting of Er and In. The phosphor for vacuum ultraviolet light excitation according to claim 4 , which is a phosphor emitting blue light which is contained by weight%. And from 0.02 to 12% by weight of Tm, claim at least a one 0.01 to 9 wt% of an alkali metal selected from the group consisting of Rb and Cs, a phosphor which emits blue light containing Ba 0.01 to 1 wt% 4. The phosphor for vacuum ultraviolet light excitation according to 4 .

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