JP2008163255A - Phosphor and light-emitting element using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rare earth borate phosphor with a high luminous efficiency and an excellent emission color. <P>SOLUTION: The phosphor comprises a borate represented by a compositional formula (M<SB>1-x-y</SB>M<SP>1</SP><SB>x</SB>M<SP>2</SP><SB>y</SB>) (B<SB>1-z</SB>M<SP>3</SP><SB>z</SB>)O<SB>3</SB>(0<x<0.5, 0<y<0.5, 0≤z<0.5, both of M and M<SP>1</SP>are at least one selected from rare-earth elements, M<SP>2</SP>is at least one selected from trivalent ions with an ionic radius smaller than that of M, and M<SP>3</SP>is one selected from tetravalent ions with an ionic radius larger than that of B). The M<SP>2</SP>may be also at least one selected from rare-earth elements In, Pd, Sb, Ti, As, Al and Ga, and the M<SP>3</SP>may be also at least one selected from Si, Ge, Ti, Mo, W, Pt and Zr. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a novel phosphor with improved luminous efficiency and emission color and a light emitting device using the same.
More specifically, a phosphor suitable for use in a plasma display panel (PDP) or a mercury-free lamp (MFL) using a rare gas discharge, and a novel phosphor with improved luminous efficiency and emission color and the use thereof The present invention relates to a light emitting element.

In recent years, PDPs are becoming popular as large displays (image display devices), and environmentally friendly MFLs are attracting attention. Currently, a rare earth borate red phosphor is mainly developed as a red phosphor for PDP or MFL, and is used in combination with a blue phosphor and a green phosphor. Currently, (Y, Gd) BO ₃ : Eu ³⁺ is used as the rare earth borate red phosphor.

  However, this rare earth borate red phosphor is required to have further improved luminous efficiency, and in the case of PDP, there is a big problem that the color purity is poor. This is because the strong emission peak is at 592 nm and the light emission is orange.

In the (Y, Gd) BO ₃ : Eu ³⁺ red phosphor, a plurality of linear emission peaks are observed due to the ff transition ( ⁵ D ₀ → ⁷ F _J ) of the emission center Eu ³⁺ . In the orange 592 nm emission, the ⁵ D ₀ → ⁷ F ₁ transition, which is a magnetic dipole transition, does not depend much on the symmetry of the crystal field, and is strongly observed in (Y, Gd) BO ₃ : Eu ³⁺ . Therefore, it is theoretically difficult to improve the color purity of (Y, Gd) BO ₃ : Eu ³⁺ .

Therefore, in practice, a phosphor such as Y (P, V) O ₄ : Eu ³⁺ has been developed as a measure for improving the color purity of the red phosphor, but the emission luminance is (Y, Gd) BO ₃ : Improvement of the color purity of (Y, Gd) BO ₃ : Eu ³⁺ is demanded, not reaching Eu ³⁺ .

The inventor has changed the composition of rare earth borate phosphors from (Y, Gd) BO ₃ : Eu ³⁺ which is currently used, so that the composition formula (M _1-xy M ¹ _x M ² _y ) borate represented by (B _1-z M ³ _z ) O ₃ (0 <x <0.5, 0 <y <0.5, 0 ≦ z <0.5 or 0 <x < The present inventors have found the possibility of improving the light emission efficiency and color purity of the rare earth borate phosphor represented by 0.5, y = 0, 0 <z <0.5).

The present invention has been derived on the basis of such findings, and boron represented by a composition formula (M _1-xy M ¹ _x M ² _y ) (B _1-z M ³ _z ) O ₃ is used. Represented by an acid salt (0 <x <0.5, 0 <y <0.5, 0 ≦ z <0.5 or 0 <x <0.5, y = 0, 0 <z <0.5) The phosphor used for PDP or MFL characterized by comprising rare earth borate is provided.

(Object of invention)
An object of the present invention is to provide a rare earth borate phosphor having high luminous efficiency and good emission color.
Another object of the present invention is to provide a light emitting device using the phosphor.

The means of the present invention taken to achieve the above object are as follows.
The present invention is a composition formula ^{_{(M 1-x-y M}} 1 x M 2 y) (B 1-z M 3 z) borate represented by _{O 3 (0 <x <0.5,0} <y <0.5, 0 ≦ z <0.5, each of M or M ¹ is at least one selected from rare earth elements, M ² is at least one selected from trivalent ions having an ionic radius smaller than M, M ³ is a phosphor composed of at least one selected from tetravalent ions having an ionic radius larger than B).

In the phosphor, M ² is at least one selected from rare earth elements, In, Pd, Sb, Ti, As, Al, and Ga, and M ³ is Si, Ge, Ti, Mo, W, Pt, and Zr. It may consist of at least one selected from

The at least one in the phosphor, M is the Y, La, Gd, at least one selected from among Lu, ^{M 1} is the Ce, Pr, Nd, Sm, Eu, Tb, Dy, Er, selected from among Yb M ² may be at least one selected from Sc, In, Pd, Ti, Al, and Ga, and M ³ may be at least one selected from Si and Ge.

The present invention is a composition formula ^{_{(M 1-x-y M}} 1 x M 2 y) (B 1-z M 3 z) borate represented by _{O 3 (0 <x <0.5,0} <y <0.5, 0 ≦ z <0.5, each of M and M ¹ is at least one selected from rare earth elements, M ² is at least one selected from divalent ions, and M ³ has an ionic radius. A phosphor composed of at least one selected from tetravalent ions larger than B).

In the phosphor, M ² is at least one selected from Ba, Pb, Sr, Ca, Pd, Pt, Mn, Zn, and Mg, and M ³ is Si, Ge, Ti, Mo, W, Pt, or Zr. You may consist of at least 1 type chosen from the inside.

The at least one in the phosphor, M is the Y, La, Gd, at least one selected from among Lu, ^{M 1} is the Ce, Pr, Nd, Sm, Eu, Tb, Dy, Er, selected from among Yb M ² may be composed of at least one selected from Ba, Sr, Ca, Pd, Pt, Zn, and Mg, and M ³ may be composed of at least one selected from Si and Ge.

The present invention relates to a borate (0 <x <0.5, y = 0) represented by a composition formula (M _1-xy M ¹ _x M ² _y ) (B _1-z M ³ _z ) O _3. , 0 <z <0.5, M or M ¹ is at least one selected from rare earth elements, M ³ is a rare earth element other than B, In, Pd, Sb, Ti, As, It is a phosphor composed of at least one selected from Al and Ga.

At least one in the phosphor, M is the Y, La, Gd, at least one selected from among Lu, ^{M 1} is the Ce, Pr, Nd, Sm, Eu, Tb, Dy, Er, selected from among Yb, M ³ may be composed of at least one selected from Al and Ga.

  Furthermore, the present invention is a light emitting device using any of the phosphors described above.

  According to the present invention, a rare earth borate phosphor having high luminous efficiency and good emission color can be obtained. In addition, a light-emitting element using the phosphor can be provided.

The phosphor of the present invention has a borate salt represented by the composition formula (M _1-xy M ¹ _x M ² _y ) (B _1-z M ³ _z ) O ₃ (0 <x <0.5, 0 <y <0.5, 0 ≦ z <0.5 or 0 <x <0.5, y = 0, 0 <z <0.5) It is characterized by.

The phosphor of the present invention has a borate salt represented by the composition formula (M _1-xy M ¹ _x M ² _y ) (B _1-z M ³ _z ) O ₃ (0 <x <0.5, 0 <y <0.5, 0 ≦ z <0.5 or 0 <x <0.5, y = 0, 0 <z <0.5) And M is a main element as a matrix and is composed of at least one rare earth element.

The phosphor of the present invention has a borate salt represented by the composition formula (M _1-xy M ¹ _x M ² _y ) (B _1-z M ³ _z ) O ₃ (0 <x <0.5, 0 <y <0.5, 0 ≦ z <0.5 or 0 <x <0.5, y = 0, 0 <z <0.5) M ¹ is a light emission center and is composed of at least one kind of rare earth element.

The phosphor of the present invention has a borate salt represented by the composition formula (M _1-xy M ¹ _x M ² _y ) (B _1-z M ³ _z ) O ₃ (0 <x <0.5, y = 0,0 <z <0.5), wherein M or M ¹ is at least one selected from rare earth elements, M ³ is It is composed of at least one selected from rare earth elements other than B, which are trivalent ions, In, Pd, Sb, Ti, As, Al, and Ga.

The phosphor of the present invention has a borate salt represented by the composition formula (M _1-xy M ¹ _x M ² _y ) (B _1-z M ³ _z ) O ₃ (0 <x <0.5, 0 <y <0.5, 0 ≦ z <0.5), and M ² is an element substituting for M to improve luminous efficiency and color Contributes to improved purity.

The phosphor of the present invention has a borate salt represented by the composition formula (M _1-xy M ¹ _x M ² _y ) (B _1-z M ³ _z ) O ₃ (0 <x <0.5, 0 <y <0.5, 0 ≦ z <0.5), and M ² is a trivalent rare earth element having an ion radius smaller than M, In , Pd, Sb, Ti, As, Al, and Ga.

The phosphor of the present invention has a borate salt represented by the composition formula (M _1-xy M ¹ _x M ² _y ) (B _1-z M ³ _z ) O ₃ (0 <x <0.5, 0 <y <0.5, 0 ≦ z <0.5), and is characterized in that M ² is Ba, Pb, Sr, Ca, Pd, Pt, Mn , Zn, Mg, at least one kind of divalent ion.

The phosphor of the present invention has a borate salt represented by the composition formula (M _1-xy M ¹ _x M ² _y ) (B _1-z M ³ _z ) O ₃ (0 <x <0.5, 0 <y <0.5, 0 ≦ z <0.5), and M ² is composed of Ba, Pb, Sr, Ca, Pd, Pt, Mn. , Zn, and Mg, when composed of at least one divalent ion, tetravalent Si or Ge ions may be simultaneously doped to maintain the charge balance.

The phosphor of the present invention has a borate salt represented by the composition formula (M _1-xy M ¹ _x M ² _y ) (B _1-z M ³ _z ) O ₃ (0 <x <0.5, 0 <y <0.5, 0 ≦ z <0.5), and M ³ is an element substituting B, and Si, Ge, Ti, It is composed of at least one selected from Mo, W, Pt, and Zr.

The phosphor of the present invention has a borate salt represented by the composition formula (M _1-xy M ¹ _x M ² _y ) (B _1-z M ³ _z ) O ₃ (0 <x <0.5, 0 <y <0.5, 0 ≦ z <0.5), and is characterized in that M ² is Ba, Pb, Sr, Ca, Pd, Pt, Mn , Zn, and Mg, when composed of at least one divalent ion, tetravalent M ³ ions may be doped at the same time in order to maintain the charge balance.

  The phosphor of the present invention is prepared by blending each metal raw material (generally as an oxide, carbonate, or hydroxide) with a predetermined composition, or adding and mixing a reaction accelerator as necessary. It is obtained by firing. Moreover, you may bake by a well-known general method.

  The phosphor of the present invention is prepared by blending raw materials of each metal (generally, as an oxide, carbonate, or hydroxide) with a predetermined composition, or after adding and mixing boric acid as necessary. It is obtained by firing.

  In order to further clarify the features of the present invention, examples are shown below, but the present invention is not limited to these examples.

  FIG. 1 is a graph (vacuum ultraviolet excitation at room temperature) showing emission spectra of each of the phosphors according to the present invention and Comparative Example 1.

[Example 1]
Y ₂ O ₃ 0.21 mol
Gd ₂ O ₃ 0.20 mol
Eu ₂ O ₃ 0.03 mol
Al ₂ O ₃ 0.06 mol
H ₃ BO ₃ 1.0 mol

After mixing the raw materials of the above composition, firing (3 hours at a temperature of 1200 ° C.), pulverization, classification, and drying are performed to _obtain (Y _0.42 Gd _0.40 Al _0.12 ) BO ₃ : Eu _0.06 . A trivalent Eu-activated red light-emitting rare earth borate phosphor represented by the composition formula was obtained. For comparison, a phosphor having a normal composition (Y _0.54 Gd _0.40 ) BO ₃ : Eu _0.06 (Comparative Example 1) was simultaneously produced under the same conditions.

The obtained phosphor and a rare earth borate phosphor (Y _0.54 Gd _0.40 ) BO ₃ : Eu _0.06 of normal composition were irradiated with a vacuum ultraviolet light source (147 nm), and the emission intensity and emission color were measured. did. The emission spectrum is shown in FIG. 1, and the emission characteristics are shown in Table 1 below.

  Compared to Comparative Example 1, in Example 1, the light emission luminance was improved by 16%, the light emission at 611 nm was increased, and the color purity of the light emission was improved.

[Example 2]
A trivalent Eu-activated red light-emitting rare earth represented by the composition formula of (Y _0.42 Gd _0.40 Mg _0.12 ) BO ₃ : Eu _0.06 by a method similar to the method described in Example 1 A borate phosphor was obtained. The emission spectrum of vacuum ultraviolet (147 nm) excitation is shown in FIG. Compared with Comparative Example 1, the light emission luminance was improved by 6% in Example 2, the light emission at 611 nm was increased, and the color purity of the light emission was improved.

[Example 3]
By a method similar to the method described in Example 1, it is represented by the composition formula of (Y _0.42 Gd _0.40 Mg _0.12 ) (B _0.88 Si _0.12 ) O ₃ : Eu _0.06. A trivalent Eu-activated red light-emitting rare earth borate phosphor was obtained. The emission spectrum of vacuum ultraviolet (147 nm) excitation is shown in FIG. Compared with Comparative Example 1, Example 3 improved the emission luminance by 11%, increased the emission of 611 nm, and improved the color purity of the emission.

  The terms and expressions used in the present specification and claims are for illustrative purposes only, and are not intended to be limiting in any way. The features described in the present specification and claims and their terms There is no intention of excluding some equivalent terms and expressions. It goes without saying that various modifications are possible within the scope of the technical idea of the present invention.

The graph which showed the emission spectrum of each Example of the fluorescent substance based on this invention, and the comparative example 1 (vacuum ultraviolet excitation in room temperature).

Claims (9)

Composition formula ^{_{(M 1-x-y M}} 1 x M 2 y) (B 1-z M 3 z) borate represented by _{O 3 (0 <x <0.5,0} <y <0.5 , 0 ≦ z <0.5, each of M or M ¹ is at least one selected from rare earth elements, M ² is at least one selected from trivalent ions having an ionic radius smaller than M, and M ³ is an ion At least one selected from tetravalent ions having a radius greater than B),
Phosphor. Composition formula ^{_{(M 1-x-y M}} 1 x M 2 y) (B 1-z M 3 z) borate represented by _{O 3 (0 <x <0.5,0} <y <0.5 , 0 ≦ z <0.5, each of M and M ¹ is at least one selected from rare earth elements, M ² is at least one selected from divalent ions, and M ³ has an ionic radius larger than B 4 Composed of at least one selected from among the valence ions),
Phosphor. Composition formula ^{_{(M 1-x-y M}} 1 x M 2 y) (B 1-z M 3 z) borate represented by _{O 3 (0 <x <0.5} , y = 0,0 <z <0.5, M or M ¹ is at least one selected from rare earth elements, M ³ is a rare earth element that is a trivalent ion other than B, In, Pd, Sb, Ti, As, Al, Ga. Composed of at least one selected from among),
Phosphor. M ² is at least one selected from rare earth elements, In, Pd, Sb, Ti, As, Al, and Ga, and M ³ is at least one selected from Si, Ge, Ti, Mo, W, Pt, and Zr. Consist of,
The phosphor according to claim 1. M ² is at least one selected from Ba, Pb, Sr, Ca, Pd, Pt, Mn, Zn, and Mg, and M ³ is at least selected from Si, Ge, Ti, Mo, W, Pt, and Zr. Consist of a kind,
The phosphor according to claim 2. M is at least one selected from Y, La, Gd, and Lu, M ¹ is at least one selected from Ce, Pr, Nd, Sm, Eu, Tb, Dy, Er, and Yb, and M ² is Sc, in, Pd, Ti, Al, at least one, ^{M 3} is selected from among Ga comprises at least one member selected Si, from among Ge,
The phosphor according to claim 1. M is at least one selected from Y, La, Gd, and Lu, M ¹ is at least one selected from Ce, Pr, Nd, Sm, Eu, Tb, Dy, Er, and Yb, and M ² is Ba, sr, at least one Ca, Pd, Pt, Zn, selected from among Mg, ^{M 3} is composed of at least one selected Si, from among Ge,
The phosphor according to claim 2. At least one M is Y, La, Gd, at least one selected from among Lu, ^{M 1} is Ce, Pr, Nd, Sm, Eu, Tb, Dy, Er, selected from among Yb, ^{M 3} is Al, Consisting of at least one selected from Ga,
The phosphor according to claim 3. Using the phosphor according to any one of claims 1 to 8,
Light emitting element.

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