JPH08120265A - Yttrium aluminate phosphor - Google Patents

Abstract

PURPOSE: To enable a high-precision image and a high-luminance brightness to be realized and maintained on a cathode ray tube of a TV, etc., without increasing the intensity of an incident electron beam by incorporating yttrium, aluminum, a specific activating element, and if necessary gallium into an yttrium aluminate phosphor. CONSTITUTION: By way of example, in the case of a terbium-activated phosphor, the raw materials including Y2 O3 , Al2 O3 , Ga2 O3 , and Tb4 O7 are mixed, coprecipitated, baked using an alkali or alkaline earth metal halide as the flux, and ground to give a phosphor contg. yttrium, aluminum, at least one activating element selected from among terbium, cerium, and europium, and if necessary gallium. The production is carried out by adjusting the amt. of the activator, conditions at each treating step, etc., by monitoring the half-width value so that, when the half-width value of hexacoordinated Al signal in the vicinity of 0ppm according to<27> Al MAS NMR, (Δν1/2 (Al(6)), is plotted against the activator concn., the relation: Δν1/2 (Al(6))>Δν1/2 (Al(6))<st> is satisfied [(Δν1/2 (Al(6))<st> is the half-width value of the standard phosphor at the same activator concn.].

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a yttrium aluminate phosphor, and more particularly to a yttrium aluminate phosphor used in a projection tube, a cathode ray tube for a color television, etc., which exhibits high brightness characteristics when excited by an electron beam.

[0002]

2. Description of the Related Art Y activated by Tb, Ce or Eu
₃ Al ₅ O ₁₂ exhibits bright fluorescence and is used in television cathode ray tubes, projection tubes, three-wavelength lamps, and the like. The yttrium aluminate phosphor to which Tb is added as an activator emits green, the one using Ce as an activator emits yellow, and the one using Eu as an activator emits red.

[0003] The market needs for phosphors are becoming finer and finer with the increase in size and quality of video equipment such as projection large-screen televisions and high-definition televisions.
Higher brightness is strongly desired. In order to display a high-definition image on a large screen, a high-density electron beam is injected, but when the current density is increased with the yttrium aluminate phosphor, the luminous efficiency of the phosphor increases with time. However, the yttrium aluminate phosphor having sufficiently high precision and high brightness has not been proposed yet, because the brightness is not sufficient for a high density screen.

[0004]

[Problems to be Solved by the Invention] Under these circumstances,
There was a need for yttrium aluminate phosphors with higher brightness characteristics at low current densities. The present invention provides an yttrium aluminate phosphor that maintains high-definition and high-luminance brightness on a CRT or projection tube of a television without increasing the intensity of an incident electron beam.

[0005]

In order to achieve the above object, the inventors of the present invention have Tb, Ce or Eu which is the emission center of the yttrium aluminate phosphor activated with at least one of Tb, Ce and Eu. As a result of thorough investigations on the existing state and distribution state of phosphor, and the structure of the phosphor crystal, it was found that an yttrium aluminate phosphor having specific NMR (nuclear magnetic resonance) characteristics has high brightness characteristics, and the present invention was reached. did.

That is, the gist of the present invention is (a) Y,
Group consisting of (b) Al, and (c) Tb, Ce and Eu
One or more activator elements selected from (d) if necessary
Is a yttrium aluminate phosphor containing Ga
I mean²⁷6 distributions around 0 ppm by Al MAS NMR
Half-width of Al signal (Δν_1/2(Al (6))) is the activation source
The standard yttrium oxide is plotted against elementary concentration.
Luminescent phosphor²⁷0pp by AlMAS NMR
Half-width of 6-coordinate Al signal near m (Δν_1/2(Al
(6))^ST) Is plotted against the activator concentration, the same
Activator concentration, Δν _1/2(Al (6))> Δν_1/2(Al
(6))^STYttrium aluminum which is characterized by
It exists in the phosphor.

The yttrium aluminate phosphor of the present invention will be described below as Y ₃ (Al _1-x Ga _x ) ₅ O ₁₂ : Ln (Ln
Represents one or more activator elements selected from the group consisting of Tb, Ce and Eu, and x represents a real number satisfying 0 ≦ x ≦ 0.6. ) Will be described as an example. In this case, the standard yttrium aluminate phosphor is Y ₃ (Al _1-x Ga _x ) ₅ O ₁₂ :
It is represented by Ln.

The present invention is²⁷By Al MAS NMR
The line width of the hexacoordinated Al signal near 0 ppm is the concentration of the activator element.
Degree is linearly proportional to
When the line width of this 6-coordinate Al signal is larger,
It is based on the fact that high brightness can be achieved. Academic of this
However, the hexacoordinated Al system near 0 ppm is not fully understood.
The spread of the line width of the gnaru peak is Tb³⁺(4f⁸),
Ce³⁺(4f¹), Eu ³⁺(4f⁶) Due to paramagnetic relaxation
16 units in one unit cell
Tetrahedral coordination Al (4 coordination Al), 24 octahedral coordination
Al (6 coordination Al) and 24 dodecahedral coordination Y (8 coordination)
Y where there is Y)₃Al_FiveO₁₂In the crystal of Tb, C
Difference in distribution of e and Eu, Tb, Ce, Eu, Y, A
It is thought that it reflects the state of bond or substitution of l and O.
Be done.

The phosphor of the present invention is Y ₃ (Al _1-x Ga _x ) ₅
O ₁₂ : Ln (Ln represents an activating element selected from Tb, Ce and Eu), which is a yttrium aluminate phosphor activated with Tb, Ce or Eu, and x has a molar composition of 0.6. If it is below, for example, Tb can be favorably used as a green phosphor. The amount of activator Tb, Ce or Eu added is usually 10 mol% or less, preferably 1 to 7 mol%.

The line width broadening of a hexacoordinated Al signal around 0 ppm by ²⁷ Al MAS NMR is represented by the half width of the signal peak (Δν _1/2 (Al (6))), and MA
Resonance frequency 78.2M by NMR using S probe
Hz, pulse width 0.6 μsec (17 ° pulse), single pulse, waiting time 2 sec, integration time is usually obtained by measuring about 3000 times. From the linear shape of the signal, the linear shape is separated by a conventional method so that the signals of 4-coordinate Al and 6-coordinate Al are bilaterally symmetric, and the line width is obtained. The full width at half maximum of this is taken as the vertical axis, and Tb, Ce, E
The u concentration is plotted on the horizontal axis.

Next, a standard line is created. First, Y₃
(Al_1-xGa_x)_FiveO₁₂: Tb, Ce or Eu standard
Make a substance. The reference material is prepared as follows.
U Molar ratio of Y corresponding to each concentration₂O₃, Al₂O₃,necessary
By Ga₂O₃For example, in the case of Tb activation, Tb_FourO₇
Mix well with a mortar etc. Next, barium fluoride
Alkaline earth metal or alkali metal halogen such as
The (F, Cl, I, Br) compound is mixed as a flux and
Fill the mixture into a heat-resistant container with a lid (quartz, alumina, etc.)
Then, it is baked at a temperature of 1450 ° C. for 3 hours. During this firing
The atmosphere is a reducing atmosphere in the case of Tb, for example N.₂-H
₂(H₂ 1 to 3%), in the case of Eu, in an oxidizing atmosphere,
For example, in oxygen or in air, and in the case of Ce, in air.
Or N₂-H₂(H₂ 1 ~ 2%) in a weak reducing atmosphere
Is performed in a neutral atmosphere (for example, in Ar). Obtained firing
Wash the product with water, hot water or a weak acid, and₃(Al_1-xGa
_x)_FiveO ₁₂: Obtain Tb, Ce or Eu standards.

[0012] In this standard substance the same as the above, ²⁷ Al
A 6-coordinate Al signal around 0 ppm is obtained by MAS NMR, and the half-value width (Δν _1/2 (Al (6)) ^ST ) is determined. In the same manner as above, Tb, C
The e or Eu concentration is plotted on the horizontal axis. The phosphor of the present invention has the same Tb, Ce or Eu concentration, and is larger than the full width at half maximum of the standard Y ₃ (Al _{1- x} Ga _x ) ₅ O ₁₂ : Tb, Ce or Eu phosphor. That is, Δν _1/2 (Al
(6))> Δν _1/2 (Al (6)) ^ST . Furthermore, Δ
ν _1/2 (Al (6)) ＞ Δν _1/2 (Al (6)) ^ST + 10H
z is preferable, and in particular, Δν _1/2 (Al (6))> Δν
_1/2 (Al (6)) ^ST + 20 Hz is preferred.

The phosphor of the present invention can be preferably produced, for example, by the following method. For example, in the case of a Tb activator, the raw materials Y ₂ O ₃ , Al ₂ O ₃ , Ga ₂ O ₃ and Tb ₄ are added in a desired composition.
Mix O ₇ well. For the mixing, preferably, a rare earth oxide oxalate or the like is used, and a coprecipitated crystal obtained by coprecipitation is used. Next, an alkaline earth metal such as barium fluoride or lithium chloride or an alkali metal halogen (F, Cl,
(I, Br) compound as a flux, and mixed in a reducing atmosphere (for example, N ₂ —H ₂ (H ₂ 1 to 3%)) 1200 to 1
Baking at a temperature of 600 ° C. for 0.5 to 6 hours. The obtained fired product is washed with water and sieved, and if necessary, lightly crushed with a ball mill or the like to obtain the product. Even in such a process or other manufacturing method, a calibration curve using a standard substance should be prepared in advance, and the full width at half maximum of the obtained phosphor should be monitored to adjust the amount of activator and each treatment condition. Can be manufactured in.

The yttrium aluminate or yttrium gallium aluminate of the phosphor of the present invention contains a small amount of other Gd, La, Lu, etc. as a part of Y within a range not impairing the effects of the present invention. It may be replaced.

[0015]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to the following examples unless it exceeds the gist thereof. 6-coordinate Al signal The full width at half maximum of the signal is measured by solid NM manufactured by Bruker.
The R apparatus MSL-300 was mounted with a 4 mm MAS probe.

The measurement conditions are as follows.

[0017]

[Table 1] Probe: MAS probe Resonance frequency: 78.2 MHz Pulse width: 0.6 μsec (17 ° pulse) Pulse series: Single pulse Rotation speed: 15000 rps Waiting time: 2 sec

Hereinafter, Y, Al, Ga and T of each sample will be described.
b, Ce or Eu molar ratio and impurity concentration are Seik
Quantification was carried out using an SPS-1200A ICP device (inductively coupled high frequency plasma emission spectrometer) and a Rigaku 3370 fluorescent X-ray device. In addition, the brightness of the phosphor is measured by an electron beam excitation device (TOPCON ABT-32).
This was performed using

Reference Examples 1 to 6 (Preparation of Y ₃ Al ₅ O ₁₂ Standard Material) Raw material powders and fluxes having the compositions shown in Table 1 below were thoroughly mixed in a dry system, and then filled in an alumina crucible, and N ₂ − Firing was performed at 1450 ° C. for 3 hours in a weakly reducing atmosphere of H ₂ (H ₂ concentration 2%). The obtained calcined product was pickled and ball-milled, then thoroughly washed with water to remove residual flux, dried at a temperature of 70 to 100 ° C., and sieved to activate Y ₃ Al ₅ O ₁₂ : Tb standard substance activated only with terbium. Got This product was powder X-ray diffraction, and both were Y ₃ Al ₅ O.
It was confirmed to be ₁₂ crystals. Further ICP
From the measurement result by the device, the amount of Tb was in agreement with the added amount within the experimental error within the experimental error. The content of Tb is shown in Table 1. When these phosphors were excited by electron beams or ultraviolet rays, all of them glowed green.

[0020]

[Table 2] Table 1 Y ₂ O ₃ Tb ₄ O ₇ Al ₂ O ₃ BaF ₂ Tb concentration gr gr gr gr mol% --------------------------------- −−−−−−−−−−− Reference example 1 34.2 0 25.8 2.1 0.0 Reference example 2 33.8 0.6 25.7 2.0 1.0 Reference example 3 33.3 1.1 25.6 2.0 2.0 Reference example 4 32.8 1.7 25.5 2.0 3.0 Reference example 5 31.9 2.8 25.3 1.9 5.0 Reference Example 6 29.7 5.4 24.8 1.8 10.0 −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− ( ²⁷ Create standard line)

For the standard substances of Reference Examples 1 to 6, ²⁷ Al
Half-width of 6-coordinate Al signal by MAS NMR (Δ
ν _1/2 (Al (6)) ^ST ) was measured and calculated. ^{The full} width at half maximum of the ²⁷ Al signal (Δν _1/2 (Al (6)) ^ST ) is shown in Table 2 together with the Tb concentration. Also, based on this, the half-value width (Δν _1/2 (Al (6)) ^ST ) of the hexacoordinated Al signal is plotted on the vertical axis, and the Tb concentration is plotted on the horizontal axis, and the relationship is plotted. The obtained standard line is shown in FIG.

[0022]

[Table 3] Table 2 Composition Tb concentration Δν _1/2 (Al (6)) ^ST mol% Hz −−−−−−−−−−−−−−−−−−−−−−−−−−−− −−−− Reference example 1 Y ₃ Al ₅ O ₁₂ 0.0 35.6 Reference example 2 (Y _0.99 Tb _0.01 ) ₃ Al ₅ O ₁₂ 1.0 75.6 Reference example 3 (Y _0.98 Tb _0.02 ) ₃ Al ₅ O ₁₂ 2.0 84.4 Reference Example 4 (Y _0.97 Tb _0.03 ) ₃ Al ₅ O ₁₂ 3.0 88.9 Reference Example 5 (Y _0.95 Tb _0.05 ) ₃ Al ₅ O ₁₂ 5.0 97.8 Reference Example 6 (Y _0.90 Tb _0.10 ) ₃ Al ₅ O ₁₂ 10.0 133.3 −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−

Example 1 32.8 g of the raw materials yttrium oxide, 1.7 g of terbium oxide and 25.5 g of aluminum oxide were weighed and mixed in a dry manner in a mortar. Then, when 200 ml of pure water was added to the dry mixed raw material, 200 g of alumina ball was added and wet mixed with a ball mill. After performing wet mixing for 5 hours, take out the slurry from the pot, dehydrate, and
It was dried at 20 ° C. for 5 hours. 2 g of barium fluoride was added to the mixed raw material powder and further mixed. This was filled in an alumina boat, and an N ₂ —H ₂ (H ₂ concentration 2%) air flow was applied at 1 minute / minute.
It was calcined at 1450 ° C. for 3 hours while flowing in with 00 ml. The obtained fired product was washed twice with 500 ml of pure water, and then, when 200 ml of pure water was used, wet mixing was performed by the same ball mill as above. Drying after wet mixing was also performed in the same manner as above. Again, add barium fluoride to 2.
5 g was added and dry mixed in a mortar. This was filled in an alumina boat and fired at 1500 ° C. for 3 hours in a N ₂ —H ₂ (H ₂ concentration 2%) air flow of 100 ml / min. The obtained phosphor was washed with 500 ml of pure water three times, and then washed twice with 500 ml of boiling pure water. Then dehydrated,
It was dried at 120 ° C. for 5 hours and passed through a sieve to obtain a phosphor.

Example 2 A phosphor was obtained in the same manner as in Example 1 except that the first firing was carried out in the atmosphere without the inflow of N ₂ -H ₂ gas stream. Comparative Example 1 Yttrium oxide 32.8 g, terbium oxide 1.7
g, aluminum oxide 25.5 g, and barium fluoride 2 g were weighed and mixed in a mortar in a dry manner. An alumina crucible was filled with the mixed raw material powder, and N ₂ —H ₂ (H ₂ concentration 2
%) Calcination was performed in an air stream at 1500 ° C. for 3 hours. The obtained fired product was washed with 500 ml of pure water three times, and then washed twice with 500 ml of boiling pure water. Then, dehydrate, 12
It was dried at 0 ° C. for 5 hours. Then, it was passed through a sieve to obtain a phosphor. MAS NMR of the phosphors of Examples 1 and 2 and Comparative Example 1
FWHM of 6-coordinate Al signal (Δν _1/2 (Al (6)))
Was measured. FIG. 3 shows the NMR chart of Example 1. The brightness was then measured. The results are shown in Table 3.

[0025]

[Table 4] Table 3 Tb concentration Full width at half maximum Luminance% Composition mol% Hz (relative evaluation) ------------------------------- --- Example 1 (Y _0.965 Tb _0.035 ) ₃ Al ₅ O ₁₂ 3.5 140 115 115 Example 2 (Y _0.965 Tb _0.035 ) ₃ Al ₅ O ₁₂ 3.5 110 105 105 Comparative Example 1 (Y _0.965 Tb _0.035 ) ₃ Al ₅ O ₁₂ 3.5 75 98 −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−

The full width at half maximum of the six-coordinate Al signal in Table 3 (Δν
The relationship between the standard line of FIG. 2 and the standard line of FIG. 2 is shown in FIG. 1 with _1/2 (Al (6))) as the vertical axis and Tb concentration as the horizontal axis. is there. As is apparent from FIG. 1, those of the examples of the present invention having excellent relative brightness have half-width values higher than the standard line. Reference Examples 7 to 13 (Preparation of Y ₃ (Al—Ga) ₅ O ₁₂ Standard Material) The raw material powders having the compositions shown in Table 4 below were thoroughly mixed in a dry system, and then filled in an alumina crucible and N ₂ —H ₂ (H ₂ concentration 2%) Firing was performed in an air stream at 1450 ° C. for 3 hours. The obtained fired product was pickled and ball-milled, then thoroughly washed with water to remove residual flux, dried at a temperature of 70 to 100 ° C., and sieved to activate Y ₃ (Al-Ga) ₅ O ₁₂ only with terbium. : Tb standard substance was obtained. Table 4 shows the content of Tb. When these phosphors were excited by electron beams or ultraviolet rays, all of them glowed green.

[0027]

[Table 5] Table 4 Y ₂ O ₃ Tb ₄ O ₇ Al ₂ O ₃ Ga ₂ O ₃ BaF ₂ Tb concentration gr gr gr gr gr mol% −−−−−−−−−−−−−−−−−− −−−−−−−−−−−−−−−−− Reference example 7 79.8 0 48.1 22.1 4.8 0.0 Reference example 8 78.8 1.3 47.9 22.0 4.7 1.0 Reference example 9 77.7 2.6 47.7 21.9 4.7 2.0 Reference example 10 76.6 3.9 47.6 21.9 4.6 3.0 Reference example 11 75.6 5.2 47.4 21.8 4.5 4.0 Reference example 12 74.6 6.5 47.3 21.7 4.5 5.0 Reference example 13 69.5 12.7 46.5 21.4 4.2 10.0 −−−−−−−−−−−−−−−−−−−− −−−−−−−−−−−−−− (Creation of ²⁷ Al signal half-width standard line)

Regarding the standard substances of Reference Examples 7 to 13, ²⁷ A
Full width at half maximum of the six-coordinate Al signal (Δ
ν _1/2 (Al (6)) ^ST ) was measured and calculated. Half-width of ²⁷ Al signal _{(Δν 1/2 (Al (6)} ) ST) are shown in Table 5 together with the Tb concentration. Also, based on this, the half-value width (Δν _1/2 (Al (6)) ^ST ) of the hexacoordinated Al signal is plotted on the vertical axis, and the Tb concentration is plotted on the horizontal axis, and the relationship is plotted. The obtained standard line is shown in FIG.

[0029]

[Table 6] Table 5 Tb concentration Full width at half maximum Composition mol% Hz −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− Reference Example 7 Y ₃ (Al _0.8 Ga _0.2 ) ₅ O ₁₂ 0.0 130 Reference Example 8 (Y _0.99 Tb _0.01 ) ₃ (Al _0.8 Ga _0.2 ) ₅ O ₁₂ 1.0 193 Reference Example 9 (Y _0.98 Tb _0.02 ) ₃ (Al _0.8 Ga _0.2 ) ₅ O ₁₂ 2.0 210 Reference Example 10 (Y _0.97 Tb _0.03 ) ₃ (Al _0.8 Ga _0.2 ) ₅ O ₁₂ 3.0 222 Reference Example 11 (Y _0.96 Tb _0.04 ) ₃ (Al _0.8 Ga _0.2 ) ₅ O ₁₂ 4.0 245 Reference Example 12 (Y _0.95 Tb _0.05 ) ₃ (Al _0.8 Ga _0.2 ) ₅ O ₁₂ 5.0 260 Reference Example 13 (Y _0.90 Tb _0.10 ) ₃ (Al _0.8 Ga _0.2 ) ₅ O ₁₂ 10 .0 340 −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−

Example 3 Yttrium oxide (75 g), terbium oxide (6.5 g), aluminum oxide (47 g) and gallium oxide (21.7 g) were weighed and mixed in a dry manner using a mortar. 25 this
When 0 ml of pure water was added, 250 g of alumina ball was added,
After performing wet mixing for 5 hours with a ball mill, the slurry was taken out from the pot, dehydrated, and dried at 120 ° C. for 5 hours. 4.5 g of barium fluoride was added to and mixed with the mixture, and the mixture was filled in an alumina boat and fired at 1450 ° C. for 3 hours while flowing an N ₂ —H ₂ (H ₂ concentration 3%) air stream of 150 ml per minute. The obtained fired product was washed twice with 750 ml of pure water and repeated twice, and when it was made into 250 ml of pure water, the same wet mixing as above was performed. Drying after wet mixing is done in the same way,
Again, 5 g of barium fluoride was added and dry mixed in a mortar. This was filled in an alumina boat, and 1500 ° C. and 3 ° C. in an N ₂ —H ₂ (H ₂ concentration 3%) air stream of 150 ml / min.
Burned for hours. The obtained phosphor was washed three times with 750 ml of pure water, and then washed twice with 750 ml of boiling pure water. It is then dehydrated and dried at 120 ° C for 5 hours, then
The phosphor was obtained through a sieve.

Example 4 A phosphor was obtained in the same manner as in Example 1 except that the first firing was carried out in the atmosphere without the inflow of N ₂ -H ₂ gas flow. Comparative Example 2 Yttrium oxide (75 g), terbium oxide (6.5 g), aluminum oxide (47 g), gallium oxide (21.7 g) and barium fluoride (4.5 g) were dry mixed in a mortar. An alumina crucible was filled with this raw material powder, and N ₂ —H ₂ (H ₂ concentration 3
%) Calcination was performed in an air stream at 1500 ° C. for 3 hours. The obtained fired product was washed with 500 ml of pure water three times, and then washed twice with 500 ml of boiling pure water. Then dehydrated and 120
It was dried at ℃ for 5 hours and then passed through a sieve to obtain a phosphor.
The full width at half maximum (Δν _1/2 (Al (6)) of the hexacoordinated Al signal was measured for the phosphors of Examples 3 to 4 and Comparative Example 2 by MAS NMR. The NMR chart of Example 4 is shown in FIG. The brightness was then measured. The results are shown in Table 6.

[0032]

[Table 7] Table 6 Tb concentration Full width at half maximum Luminance% Composition mol% Hz (relative evaluation) ------------------------------- −−−−− Example 3 (Y _0.95 Tb _0.05 ) ₃ (Al _0.8 Ga _0.2 ) ₅ O ₁₂ 5 300 110 Example 4 (Y _0.95 Tb _0.05 ) ₃ (Al _0.8 Ga _0.2 ) ₅ O ₁₂ 5 270 106 Comparison Example 2 (Y _0.95 Tb _0.05 ) ₃ (Al _0.8 Ga _0.2 ) ₅ O ₁₂ 5 222 98 −−−−−−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−

Half-width of six-coordinate Al signal in Table 6 (Δν
FIG. 4 shows the relationship between the standard line of FIG. 5 and the standard line of FIG. 5 plotted by plotting the _1/2 (Al (6))) on the vertical axis and the Tb concentration on the horizontal axis. is there. As is clear from FIG. 4, the examples of the present invention having excellent relative luminance have a half width value higher than the standard line.

[0034]

INDUSTRIAL APPLICABILITY The phosphor of the present invention has a high brightness and can achieve a sufficiently high brightness without being irradiated with a high-density electron beam, and is useful as a high brightness phosphor.

[Brief description of drawings]

FIG. 1 is a graph showing the relationship between the half-value width (Δν _1/2 (Al (6))) of the hexacoordinated Al signal of the phosphor of the present invention and the Tb concentration, and the relationship with the standard line.

FIG. 2 Full width at half maximum (Δν of 6-coordinate Al signal of standard substance)
₂ is a graph showing the relationship between _1/2 (Al (6)) ^ST ) and Tb concentration.

3 is an NMR chart of the yttrium aluminate phosphor of Example 1. FIG.

FIG. 4 shows the relationship between the half-value width (Δν _1/2 (Al (6))) and the Tb concentration of the hexacoordinated Al signal of the phosphor of the present invention (containing Ga).
And a graph showing the relationship with the standard line.

FIG. 5 is a graph showing the relationship between the half-value width (Δν _1/2 (Al (6)) ^ST ) of the hexacoordinated Al signal of the standard substance (containing Ga) and the Tb concentration.

6 is an NMR chart of the yttrium aluminate phosphor of Example 4. FIG.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroshi Uchida 1060 Narita, Odawara-shi, Kanagawa Kasei Optonix Co., Ltd. (72) Inventor Chisato Miura 1000, Kamoshida-cho, Midori-ku, Yokohama-shi, Kanagawa Inside the Research Institute (72) Inventor, Hase Minami 1060 Narita, Odawara-shi, Kanagawa Kasei Optonix Co., Ltd.

Claims (3)

[Claims] 1. (a) Y, (b) Al, and (c) T
a yttrium aluminate phosphor containing at least one activator element selected from the group consisting of b, Ce and Eu, and (d) Ga if necessary, ²⁷ Al MAS NM
The half-value width (Δν _1/2 (Al (6))) of the six-coordinate Al signal near 0 ppm by R was plotted against the concentration of the activator element, and the standard yttrium aluminate phosphor ²⁷ A
l When the half-value width (Δν _1/2 (Al (6)) ^ST ) of the 6-coordinate Al signal near 0 ppm by MAS NMR was plotted against the activator concentration, Δν was the same at the same activator concentration.
Yttrium aluminate phosphor, characterized in that _1/2 (Al (6))> Δν _1/2 (Al (6)) ^ST . Wherein _{Y 3 (Al 1-x Ga} x) 5 O 12: Ln (Ln
Represents one or more activator elements selected from the group consisting of Tb, Ce and Eu, and x represents a real number satisfying 0 ≦ x ≦ 0.6. ), And the standard yttrium aluminate phosphor is represented by Y ₃ (Al _1-x Ga _x ) ₅ O ₁₂ : Ln. 1. The yttrium aluminate phosphor according to 1. 3. Δν _1/2 (Al (6)) and Δν _1/2 (Al (6)) ^ST
Is Δν _1/2 (Al (6)) ＞ Δν _1/2 (Al (6)) ^ST
+10 Hz, The yttrium aluminate phosphor according to claim 1 or 2, which is characterized in that.