JPH1017859A - Method for extracting constituent of fluorescent substance from fluorescent substance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To extract a constituent of fluorescent substance other than rare earth compds. from a fluorescent substance. SOLUTION: A Ba0.9 Eu0.1 MgAl10 O17 fluorescent substance is mixed with an aluminum fluoride reactant for 1hr by using a mortar (the reactant addition step). The resultant mixture is put in an alumina-made boat, which is then placed in an alumina-made core tube in a tubular atmospheric furnace. Nitrogen gas and hydrogen gas are introduced into the core tube, and the temp. of the mixture is elevated at a temp. rise rate of 400 deg.C/hr by energizing an electric heater and is kept at 1,200 deg.C for 2hr. Then, the mixture is cooled at a temp. fall rate of 200 deg.C/hr to room temp. (the thermal reaction step). After the reaction step, the thermal reaction product of the mixture remains in the boat. Thus, after adding the reactant to a fluorescent substance, the resultant mixture is heated to give a thermal reaction product and a part of the product is subjected to extraction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for reusing a phosphor widely used for a lighting device such as a fluorescent lamp and a display device such as a plasma display.
The present invention relates to a technique for extracting a phosphor constituent from a phosphor.

[0002]

2. Description of the Related Art Conventionally, in a technique for extracting a phosphor component from a phosphor, for example, resources and materials '95 (Autumn Games), p. 9 and JP-A-60-161330, rare earth elements in the phosphor composition have been extracted. The rare earth to be extracted is, for example, europium.

[0003] However, in the conventional technique for extracting a phosphor constituent from a phosphor, a phosphor constituent other than a rare earth element is not extracted from the phosphor. For this reason, for example, phosphor components other than rare earths, such as aluminum, are not extracted from the phosphor and reused, but are also discarded. With increasing awareness of environmental protection and environmental preservation, there is a demand for reusing discarded phosphor components.

[0004]

In the conventional technique for extracting a phosphor composition from a phosphor, the phosphor composition other than the rare earth element is not extracted from the phosphor and is not reused. In order to dispose of the phosphor as it is, not only is the phosphor component not effectively used, but also the amount of waste in the production of the phosphor increases.

[0005] It is an object of the present invention to provide a method for extracting a phosphor component other than a rare earth from a phosphor. At the same time, the object is to reduce the amount of waste in the production of the phosphor.

[0006]

Means for Solving the Problems To achieve the above object, a method for extracting a phosphor component from a phosphor of the present invention mainly comprises a reactant adding step, a heating reaction step, and a separation step. And configure.

Hereinafter, the method for extracting a phosphor constituent from the phosphor of the present invention will be described in detail. In the reactant adding step, a reactant is added to the phosphor. In the next heating reaction step, heating is performed so that the phosphor and the reactant chemically react. In the last separation step, the phosphor constituents in the heated reactant are separated. The phosphor may be a phosphor that can be synthesized using a reaction accelerator, and the reactant may be the above-described reaction accelerator. The reaction accelerator used as the reactant includes aluminum fluoride. When aluminum fluoride is used as the reactant, the phosphor is
The _1-x Eu _x MgAl ₁₀ Formula compound represented by the O ₁₇ may be a phosphor mainly.

The reactant is aluminum fluoride and the phosphor is Ba.
_1-x Eu x in the case of the MgAl ₁₀ O ₁₇ phosphor is to react with aluminum fluoride and _{Ba 1-x Eu x MgAl 10} O 17 _{phosphor, Ba 1-x Eu x MgF} 4 and aluminum oxide After heating to a mixture, the mixture is acid-treated to form Ba.
_1-x Eu x separates MgF ₄ and aluminum oxide, to extract the aluminum oxide.

[0009]

Embodiments of the present invention will be described below. FIG. 1 is a flowchart showing one embodiment of a method for extracting a phosphor constituent from a phosphor according to the present invention.

First, a reactant is added to the phosphor and mixed. Heating the phosphor and reactant produces a heated reactant. Since the heated reactant is composed of multiple types of phosphor constituents,
Separating the phosphor constituents individually extracts the phosphor constituents. The phosphors that can be used include Ba _1-x E
There is a phosphor mainly composed of the compound represented by the formula of u _x MgAl ₁₀ O _17, as the reactant, there is aluminum fluoride. Further, using aluminum fluoride as a reactant, B
Aluminum oxide is a phosphor component that can be extracted from the phosphor represented by the chemical formula of a _1-x Eu _x MgAl ₁₀ O ₁₇ .

[0011] As an example of the present invention, a method of the phosphor, to extract the aluminum oxide phosphor composition represented by the chemical formula _{Ba 0.9 Eu 0 .1 MgAl 10 O} 17 with aluminum fluoride reactant Will be described with reference to FIG.

First, Ba _0.9 Eu having a molar ratio of 1: 4/3 is used.
_{A 0.1} MgAl ₁₀ O ₁₇ phosphor and an aluminum fluoride reactant are prepared. The above-mentioned Ba _0.9 Eu _0.1 MgAl ₁₀ O ₁₇ and aluminum fluoride are mixed for 1 hour using a mortar (reactant addition step).

Next, the mixture 1 is charged into an alumina boat 2 and placed inside an alumina furnace tube 3 of a tubular atmosphere furnace. A nitrogen gas 4 and a hydrogen gas 5 filled in a gas cylinder are introduced into a furnace tube, and discharged into the atmosphere via a bubbler 6. The flow rates of the nitrogen gas and the hydrogen gas are controlled to be 380 cc / min and 20 cc / min, respectively. The heater 7 was energized to increase the temperature at a rate of 400 ° C./hour,
Heat at 200 ° C. for 2 hours. After that, the cooling rate is 200 ° C
/ Hour to room temperature (heating reaction step).

After the heating reaction step, the mixture 1 is placed in a boat.
The heated reactant remains. FIG. 3 shows the X-ray diffraction pattern of the heated reaction product. FIG. 3 shows that the heated reactant was Ba _0.9 Eu _0.1 Mg.
It shows that the compound represented by the chemical formula of F ₄ and aluminum oxide are a mixture mainly. 3, the heating reaction step, the Ba _0.9 Eu _0.1 MgAl ₁₀ O ₁₇ phosphor and aluminum fluoride reactant in a chemical reaction, Ba _0.9
It also indicates that it is a mixture of the compound represented by the chemical formula of Eu _0.1 MgF ₄ and aluminum oxide. This reaction formula is shown in (Chemical Formula 1) for reference.

[0015]

Embedded image

(Formula 1) is 1 mol of Ba _0.9 Eu _0.1 M
(4/3) mol of aluminum fluoride reactant acts on the gAl ₁₀ O ₁₇ phosphor to form 1 mol of Ba _0.9 Eu _0.1 Mg
F ₄ compound (17/3) have been shown to produce an aluminum oxide mol.

Finally, in a beaker containing 50% dilute nitric acid diluted with pure water, place the above heated reactant, ie, Ba _0.9
A mixture of the Eu _0.1 MgF ₄ compound and aluminum oxide is charged. After stirring the heated reactant in dilute nitric acid for 30 minutes using a glass rod, the powdery solid in the beaker is filtered off using a filter paper. Thereafter, the powdery solid that has been filtered off is washed with running running pure water for 10 minutes (separation step).

FIG. 4 is an X-ray diffraction pattern of the powdery solid after washing with pure water, ie, the separated extract.

FIG. 4 shows that the extract mainly contains aluminum oxide.
Indicates that the substance is a body,
Depending on the method of extracting the phosphor constituents, Ba_0.9Eu_0.1Mg
Al _TenO₁₇From phosphor to aluminum oxide, which is a phosphor constituent
This indicates that the extraction of the chromium was successful.

[0020] The reason why the substance composed mainly of aluminum oxide can be extracted is that the Ba _0.9 Eu _0.1 MgF ₄ compound is dissolved in nitric acid solution, for aluminum oxide does not dissolve, in the separation step, Ba to dissolve
_{This is because the 0.9} Eu _0.1 MgF ₄ compound is filtered, and the aluminum oxide is filtered off.

The present invention comprises a reactant adding step of adding a reactant to a phosphor, a heating reaction step of heating the phosphor and the reactant, and a separation step of separating a phosphor constituent from the heated reactant. The present invention relates to a method for extracting a phosphor constituent from a phosphor characterized by being a main constituent.

Therefore, the main steps are a reactant adding step of adding a reactant to the phosphor, a heating reaction step of heating the phosphor and the reactant, and a separation step of separating the phosphor constituent from the heated reactant. The type of the phosphor or the reactant is not limited as long as it is configured. The heating method and heating conditions in the reactant addition step, and the method for separating or extracting the phosphor constituents in the separation step are not limited.

Incidentally, in the synthesis of the phosphor, a reaction accelerator is used to assist the crystal growth of the phosphor. The reaction accelerator is called a flux. The reaction accelerator has a function of chemically reacting with the phosphor to generate a substance having a melting property. Ba _0.9 described in Examples
In the synthesis of the Eu _0.1 MgAl ₁₀ O ₁₇ phosphor, aluminum fluoride as a reactant is used as a reaction accelerator. This indicates that the reaction accelerator used in the synthesis of the phosphor can be used as the reaction agent. That is, according to the method for extracting a phosphor constituent from the phosphor of the present invention, a reaction accelerator is added to a phosphor that can be synthesized using a reaction accelerator, and a heating reaction step and a separation step are performed. In principle, a phosphor composition can be extracted from a phosphor that can be synthesized using a reaction accelerator.

[0024]

As described above, according to the present invention, it is possible to provide a technique for extracting a phosphor component from a phosphor, which extracts a phosphor component other than a rare earth element from the phosphor. Further, the amount of waste in the production of the phosphor can be reduced.

[Brief description of the drawings]

FIG. 1 is a flowchart illustrating a method for extracting a phosphor constituent from a phosphor according to the present invention.

FIG. 2 is a diagram showing an embodiment of a method for extracting a phosphor constituent from a phosphor according to the present invention.

FIG. 3 is a view showing an X-ray diffraction pattern of a heated reaction product according to the present invention.

FIG. 4 shows an X-ray diffraction pattern of the extract according to the present invention.

[Explanation of symbols]

 Reference Signs List 1 mixture 2 boat 3 furnace tube 4 nitrogen gas 5 hydrogen gas 6 bubbler 7 heater

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical indication location H01J 9/50 H01J 9/50 B // C01F 17/00 C01F 17/00 D (72) Inventor Shigeru Horii 1006 Kadoma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Tomizo Matsuoka 1006 Kadoma Kadoma, Kadoma City, Osaka Pref.

Claims (5)

[Claims] 1. A reactant adding step of adding a reactant to a phosphor, a heating reaction step of heating the phosphor and the reactant, and a separation step of separating a phosphor constituent from the heated reactant are mainly performed. A method for extracting a phosphor constituent from a phosphor. 2. The method according to claim 1, wherein the phosphor is a phosphor that can be synthesized using a reaction accelerator, and the reactant is a reaction accelerator. Method. 3. The method according to claim 1, wherein the reactant is aluminum fluoride. 4. A phosphor mainly comprising a compound represented by a chemical formula of Ba ₁ -xE _x MgAl ₁₀ O ₁₇ ,
2. The method for extracting a phosphor composition from a phosphor according to claim 1, wherein the phosphor composition to be extracted is aluminum oxide. 5. A reactant adding step of adding aluminum fluoride to a phosphor mainly comprising a compound represented by a chemical formula of Ba ₁ -xE _x MgAl ₁₀ O ₁₇ , and heating the phosphor and the aluminum fluoride. A method of extracting a phosphor constituent from a phosphor, which mainly comprises a heating reaction step, and a separation step of separating aluminum oxide of the phosphor constituent from the heated reactant.