JPH07216354A - Luminescent material - Google Patents

Abstract

PURPOSE:To obtain a material which can emit visible light as a result of irradiation with infrared rays in one or two wavelength regions, has high luminescent intensity and suffers less from deterioration due to absorbed moisture by making it of a rare earth oxyhalide having a specified composition. CONSTITUTION:This material is the one represented by the composition of formula I (wherein A is at least one member selected from among Sc, Y, La, Gd, Yb and Lu; y=0.01; x+y=1; and X is Br or a combination of Br with C1). When this material is irradiated with light in a wavelength region of 0.95-1.1mum or in a wavelength region of 1.48-1.58mum, it can emit visible light in response to at least either irradiation of the regions. Further, the material in the title is the one represented by the composition represented by formula II (wherein z <=0.8), and when it is irradiated with light in a wavelength region of 0.95-1.1mum or in a wavelength region of 1.48-1.58mum, it can emit visible light in response to at least either irradiation. The compounds of formulas I and II can be desirably used to detect ultraviolet rays in wavelength regions of 0.95-1.1mum and 1.48-1.58mum.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The compound of the present invention has a wavelength of 0.95.
μm to 1.10 μm band and wavelength 1.48 μm to 1.58
The present invention relates to a light emitting body used for detecting infrared rays in the μm range.

[0002]

2. Description of the Related Art Conventionally, compounds for this type of light-emitting material are
a or a low oxygen fluoride or anhydrous chloride having a rare earth element as a host element, where 100 is the lowest excitation light intensity that allows visual confirmation of visible light emitted by the fluoride luminescent material, In the case of a chloride luminescent material, the excitation light intensity is 50, which can be visually confirmed. Further, when the excitation light intensities are equal, assuming that the emission intensity from the fluoride luminous body is 100, the chloride luminous body is 1000, and the sensitivity and the emission intensity of the fluoride luminous body are inferior to those of the chloride luminous body. Furthermore, the average particle size of the above-mentioned fluoride light emitting powder is 100 μm.
However, when the average particle diameter is set to 20 μm, the emission intensity becomes as weak as 25. On the other hand, the chloride luminous body has a strong hygroscopic property, and the luminous intensity deteriorates to 30% or less of the initial value before moisture absorption when left in the air for several hours, which makes molding work in the air difficult. .

[0003]

Fluoride luminescent materials which are stable to humidity are inferior in sensitivity and luminescent intensity, and when the particle size is reduced, the luminescent intensity is further reduced. Further, in a chloride luminescent material having excellent sensitivity and luminescence intensity, it is difficult to carry out the molding operation in the atmosphere because the luminescence intensity is remarkably lowered by moisture absorption. Further, both the fluoride light emitter and the chloride light emitter, the composition of the light emitter that emits visible light in the wavelength range of excitation light of 0.95 μm to 1.10 μm and the wavelength range of excitation light 1.
Since the composition of the luminescent material that emits visible light is different from 48 μm to 1.58 μm, separate luminescent materials that react in each wavelength range and emit visible light were required.

Therefore, the object of the present invention is that the sensitivity and emission intensity of the chloride luminescent material are not inferior even after being left in the atmosphere for several hours, and that the excitation wavelength range is 0.95 μm even with one composition. ~ 1.10 µm and 1.48 µm ~ 1.58
It is to find an illuminant capable of emitting visible light in response to light in each wavelength region when irradiated with light in one or both wavelength regions of μm.

[0005]

[Means for Solving the Problems] The composition formula is A _1-xy Yb _x E
r _y OX (where A is one or more of Sc, Y, La, Gd, Yb and Lu, and y ≧ 0.01,
x + y ≦ 1. X is Br, or Br and Cl), and is a rare earth oxyhalide compound luminescent material having a composition represented by Ba _1-z Er _z O
1. A Ba oxyhalide compound luminescent material having a composition represented by _{1/4 (2 + z)} X (where Z ≦ 1, X is Br, or Br and Cl), having a wavelength of 0.95 μm. ~ 1.
When excited by irradiation with light in the infrared region of either of 10 μm and a wavelength of 1.48 μm to 1.58 μm, it emits visible light (especially red light). Halide compound luminous body or B
The a-oxyhalide compound enables infrared detection that can be visually confirmed with respect to infrared rays in one or two regions.

[0006]

The conventional luminous body is a halide having Ba or a rare earth element as a host element, but it is only a fluoride and a chloride, and bromide and iodide have not been considered. In addition, bromide and iodide were expected to have even higher sensitivity and emission intensity because chloride had greater sensitivity and emission intensity than fluoride.

Next, considering the stability of the host element halide, BaF ₂ , BaCl ₂ , BaCl ₂ .2H ₂ O, Ba
When the standard entropies of Br ₂ , BaBr ₂ .2H ₂ O, YF ₃ , and YCl ₃ .6H ₂ O were compared, they were 96.
4,123.7,203,146,407,100,3
85 (unit: J / K · mol), and fluoride is more stable than chloride. Also, the ionic radius of halogen (unit:
Now frying Angstroms), ^F -: 1.19, C
^{l -: 1.67, Br -:} 1.82 and ^I -: 2.06, as the ionic radius increases, since the reduced stability after binding, bromide becomes unstable than chloride. Therefore, when a rare earth is used as a host element, it is an oxyhalide that is more stable than a halide except fluoride, and
When a was used as the host element, it was decided to study a composition having high sensitivity and high emission intensity with an oxyhalide including bromide.

However, as a method for producing a rare earth oxyhalide, it is general to prepare it by subjecting a rare earth halide hydrate to high temperature treatment in an inert gas, but since rare earth fluoride is more stable than an oxide, Rare earth oxyfluoride cannot be produced by this production method. Further, Ba oxyhalide can be obtained by subjecting Ba halide hydrate to high temperature treatment in an inert gas. On the other hand, rare earth oxyhalides and B
In a oxyhalide, since rare earth fluoride, barium fluoride, rare earth chloride, and barium chloride having a high oxygen content have low emission intensity, rare earth oxybromide, barium oxybromide, and rare earth oxyiodide, barium oxyiodide are used. A composition with high sensitivity and high emission intensity was examined with Dyde.

The energy of the light applied to the light emitter is Y
It is accumulated as excitation of 4f orbital electrons of b ion and Er ion. Compared to the excitation lifetime of the Er ion 4f orbital electron, Y
Since the excitation life of the b-ion 4f orbital electron is sufficiently short, Yb
When the ion electron falls from the excited state to the ground state, the energy released is transferred to the Er ion 4f orbital electron,
The r-ion 4f orbital electrons are further excited to emit a plurality of stages of potential energy as visible light.

That is, the Yb ion acts as a sensitizer,
Er ion acts as an activator, and energy transfer is Y
The phonons released from the b ions depend on the crystal lattice of the host compound. However, when Yb ions are excessive compared with Er ions, the energy accumulated in Yb4f orbital electrons becomes saturated and is released as heat, and the emission intensity of visible light from the light emitting body is reduced.

However, in the present invention, the halides other than fluoride have a large deliquescent property in that the powders are made finer and the performance is maintained in the atmosphere, and it is difficult to maintain the crystalline state in the atmosphere. Therefore, rare earth oxyhalides and barium oxyhalides were used.

[0012]

EXAMPLES Examples of the present invention will be described in detail below.

Example 1 A rare earth oxyhalide luminescent material having a composition represented by LnOBr was prepared according to the steps shown in Table 1. Here, Ln represents Y, Yb, and Er in the formula, and the ratio thereof was set to 75: 20: 5 in molar ratio.

[0014]

[Table 1]

The outer diameter of the produced powdery luminous body sample was 6
It was filled in a quartz cell of 0 mm x 50 mm x 7 mm, irradiated with 1.06 μm light from a light source (YAG: Xe excitation), and emitted light from the light emitter was a spectroscope AQ-6310B manufactured by Ando Electric Co., Ltd.
Was measured using the measurement system shown in FIG.

The measurement results are shown in FIG. The horizontal axis represents wavelength and the vertical axis represents emission intensity (arbitrary unit). Further, FIG. 1B shows a result obtained by irradiating the light-emitting body with a laser diode (LD) light having a wavelength of 1.53 μm and measuring the emitted light from the light-emitting body by the measurement system shown in FIG. 12B.

Example 2 A phosphor sample prepared in the same manner as in Example 1 was stored at 20 ° C. and a humidity of 50%, and a small amount was transferred to a closed container every 4 hours from the start of storage until 48 hours. Irradiate the sample every 4 hours with 1.06 μm light,
The time-dependent change (time-dependent change) of the emission intensity of visible light emitted from the light-emitting body was measured by the Hitachi Fluorometer 850 as shown in FIG.
It measured by the measuring system shown in. The results are shown in Figure 2. The horizontal axis represents time, and the vertical axis represents emission intensity (arbitrary unit).

Example 3 A rare earth oxyhalide luminescent material having a composition represented by LnOX was prepared according to the steps shown in Table 2. Here, in the formula, Ln represents Y, Yb and Er, and the ratio thereof is fixed at a molar ratio of 75: 20: 5, while X is composed of Br and Cl, and LnOBr: LnOCl.
Is a molar ratio of 100: 0, 99.99: 0.01,9
9.97: 0.03, 99.95: 0.05, 99.90:
0.10, 99.70: 0.30, 99.5: 0.5, 99.
0: 1.0, 97.0: 3.0, 95.0: 5.0, 90:
Twelve kinds of luminescent material samples were prepared by adjusting to 10 and 80:20.

[0019]

[Table 2]

These prepared phosphor samples were used in Example 1.
The same quartz cell as used in 1. was filled, irradiated with 1.06 μm light, and the visible light emitted from the luminescent material was measured with a Hitachi Fluorometer 850. The results are shown in Fig. 3. In the figure, the horizontal axis represents the LnOCl concentration (mol%) and the vertical axis represents the emission intensity (arbitrary unit).

Example 4 A rare earth oxyhalide luminescent material having a composition represented by LnOBr was prepared according to the steps shown in Table 1. Here, Ln represents Y, Yb and Er in the formula, and the molar ratio thereof is 80: 20: 0, 79.9: 2.
0: 0.1, 79.7: 20: 0.3, 79.5: 20:
0.5, 79.0: 20: 1.0, 77.0: 20.0: 3.
0.75.0: 20.0: 5.0, 70.0: 20.0: 1
0.0, 65.0: 20.0: 15.0, 60.0: 20.
Eleven kinds of luminescent material samples of 0: 20.0 and 50.0: 20.0: 30.0 were prepared.

The above luminescent material sample was filled in the same quartz cell as used in Example 1 and irradiated with 1.06 μm light,
Hitachi Fluorometer 85
It was measured by 0. The results are shown in Fig. 4. E on the horizontal axis in the figure
rOBr concentration (mol%), vertical axis shows emission intensity (arbitrary unit)
Is taking.

Example 5 A rare earth oxyhalide luminescent material having a composition represented by LnOBr was prepared according to the steps shown in Table 1. Here, Ln is Y, Yb, and Er, and the concentration ratio is 95: 0: 5.0, 94.9: in molar ratio.
0.1: 5.0, 94.7: 0.3: 5.0, 94.5: 0.
5: 5.0, 94.0: 1.0: 5.0, 92.0: 3.0:
5.0, 90.0: 5.0: 5.0, 85.0: 10.0:
5.0, 80.0: 15.0: 5.0, 75.0: 20.0:
5.0, 65.0: 30.0: 5.0, 55.0: 40.0:
5.0, 45.0: 50.0: 5.0, and 35.0: 6
Eleven kinds of luminescent material samples consisting of 0.0: 5.0 were measured in the same manner as in Example 4.

The results are shown in FIG. In the figure, the horizontal axis is YbOB
r concentration (mol%), and the vertical axis represents emission intensity (arbitrary unit).

(Embodiment 6) FIG. 6 shows the result when a light-emitting body sample manufactured under the same conditions as in Embodiment 4 was irradiated with 1.53 μm light from an LD as a light source. FIG. 6 is a characteristic diagram showing the relationship between ErOBr concentration (mol%) and emission intensity (arbitrary unit).

(Embodiment 7) FIG. 7 shows the result when a light emitting sample prepared under the same conditions as in Embodiment 5 was irradiated with 1.53 μm light from an LD as a light source. FIG. 7 shows YbOBr.
It is a characteristic view which shows the relationship between concentration (mol%) and emission intensity (arbitrary unit).

Example 8 The composition is Ba _1-z Er _z O
A barium oxyhalide luminescent material represented by _{1/4 (2 + z)} Br was produced according to the steps shown in Table 3. Where z in the formula
Was set to 0.2.

[0028]

[Table 3]

The produced powdery luminescent material sample was used in Example 1.
In the same manner as above, a quartz cell with external dimensions of 60 mm x 50 mm x 7 mm is filled and irradiated with 1.53 μm light from a light source (LD).
The radiant light from the light emitter is used as a spectroscope AQ-6310 manufactured by Ando Electric Co., Ltd.
B was used and the measurement was performed using the measurement system shown in FIG. The measurement result is shown in FIG. In the figure, the horizontal axis represents wavelength and the vertical axis represents emission intensity (arbitrary unit).

(Example 9) A phosphor sample prepared in the same manner as in Example 8 was stored at 20 ° C and a humidity of 50%, and a small amount was transferred to a hermetically sealed container every 4 hours from the start of storage until 48 hours. Irradiate the sample every 4 hours with 1.53 μm light,
The emission intensity of visible light was measured. The measurement result is shown in FIG.
The horizontal axis represents time, and the vertical axis represents emission intensity (arbitrary unit).

(Example 10) The composition was Ba _1-z Er _z O.
A barium oxyhalide luminescent material represented by _{1/4 (2 + z)} X was prepared according to the steps shown in Table 3. Here, z in the formula is set to 0.2. On the other hand, X consists of Br and Cl, and Br:
The molar ratio of Cl is 100: 0, 99.99: 0.0.
1,99.97: 0.03,99.95: 0.05,99.
9: 0.1, 99.7: 0.3, 99.5: 0.5,99.
0: 1.0, 97.0: 3.0, 95.0: 5.0, 90:
Twelve kinds of luminescent material samples were prepared by adjusting to 10 and 80:20.

These prepared phosphor samples were used in Example 1.
The same quartz cell as used in 1. was filled with 1.53 μm light, and the visible light emitted from the light emitter was measured with a Hitachi Fluorometer 850. The results are shown in Fig. 10. In the figure,
The horizontal axis represents the concentration of Ba _0.8 Er _0.2 O _0.55 Cl (mol%), and the vertical axis represents the emission intensity (arbitrary unit).

Example 11 The composition is Ba _1-z Er _z O.
A barium oxyhalide luminescent material represented by _{1/4 (2 + z)} Br was produced according to the steps shown in Table 3. Where z in the formula
To 0, 0.01, 0.03, 0.05, 0.10, 0.2
0, 0.30, 0.40, 0.50, 0.60 and 0.7
Eleven kinds of luminescent material samples of 0 were prepared.

The above phosphor sample was filled in the same quartz cell as used in Example 1 and irradiated with 1.53 μm light,
Visible light emitted from the illuminant was measured by Hitachi Fluorometer 850. The results are shown in Fig. 11. In the figure, the horizontal axis is z,
The vertical axis represents the emission intensity (arbitrary unit).

[0035]

EFFECTS OF THE INVENTION According to the present invention, 1) high emission intensity is 2) less deterioration due to moisture absorption than conventional products 3) emission intensity does not change due to particle size, so molding is easy 4) simple equipment Manufacturable 5) It has become possible to provide a light-emitting body having the advantage that visible light emission excited in a plurality of wavelength regions occurs with one composition.

[Brief description of drawings]

FIG. 1 is a characteristic diagram showing an emission characteristic of a LnOBr luminescent material according to Example 1 of the present invention when excited by 1.06 μm excitation light. Figure 1
(A) is 1.06 μm excitation, and FIG. 1 (b) is 1.53 μm.
The characteristic view showing the case of μm excitation.

FIG. 2 is a characteristic diagram showing changes over time in the emission intensity of the LnOBr luminescent material according to Example 2 of the present invention.

FIG. 3 is an L of an LnOX light emitter according to Example 3 of the present invention.
The characteristic view which shows the relationship between nOCl density | concentration and luminescence intensity.

FIG. 4 is a characteristic diagram showing the relationship between the ErOBr concentration and the emission intensity (1.06 μm excitation) of the LnOBr luminescent material according to Example 4 of the present invention.

FIG. 5 is a characteristic diagram showing the relationship between the YbOBr concentration and the emission intensity (1.06 μm excitation) of the LnOBr luminescent material according to Example 5 of the present invention.

FIG. 6 is a characteristic diagram showing the relationship between the ErOBr concentration and the emission intensity (1.53 μm excitation) of the LnOBr luminescent material according to Example 6 of the present invention.

FIG. 7 is a characteristic diagram showing the relationship between the YbOBr concentration and the emission intensity (1.53 μm excitation) of the LnOBr luminescent material according to Example 7 of the present invention.

FIG. 8 is a characteristic diagram showing emission characteristics of a Ba oxyhalide luminescent material according to Example 8 of the present invention under excitation light of 1.53 μm.

FIG. 9 is a characteristic diagram showing changes with time in emission intensity of a Ba oxyhalide luminescent material according to Example 9 of the present invention.

FIG. 10 is a characteristic diagram showing the relationship between the Ba _1-z Er _z O _{1/4 ( 2 + z)} Cl concentration and the emission intensity of the Ba oxyhalide luminescent material according to Example 10 of the present invention.

FIG. 11: Er concentration and emission intensity (1.53 μm excitation) of Ba oxyhalide luminescent material according to Example 11 of the present invention.
The characteristic view showing the relationship with.

12A and 12B are views showing a measuring section for measuring emitted light from a light emitting body, FIG. 12A shows a case of irradiating with 1.06 μm light, and FIG. 12B shows irradiation with 1.53 μm of light. FIG.

[Explanation of symbols]

 1 Light source (1.06 μm) 11 Light source (1.53 μm) 2 Sample chamber 3 Cell 4 Spectrometer 5 Excitation light 6 Emission light M Reflector S Sample

Claims (2)

[Claims] 1. A composition of A _1-xy Yb _x Er _y OX (provided that
A is one or more of Sc, Y, La, Gd, Yb and Lu, and y ≧ 0.01 and x + y ≦ 1. X is Br, or Br and Cl) and has a wavelength of 0.95 μm to 1.10 μm region and 1.48 μm to 1.5.
A light-emitting body, which emits visible light in both wavelength regions or one wavelength region when irradiation is performed independently in the 8 μm region. 2. The composition has a composition of Ba _{1 -z} Er _z O _{1/4 (2 + z)} X (where z ≦ 0.8, X is Br, or Br and Cl).
In the case of irradiation with wavelengths of 0.95 μm to 1.10 μm range and 1.48 μm to 1.58 μm range respectively, visible light is emitted in both wavelength ranges or one of the wavelength ranges. A luminous body characterized by the above.