JP4528948B2 - Phosphor glass material - Google Patents

Description

  The present invention relates to a phosphor glass material useful as a display, illumination, recording element, and the like, and a method for producing the same.

Conventionally, as the solid phosphor, (1) a crystalline or amorphous body containing an element exhibiting fluorescence such as rare earth elements or transition metal elements, (2) an organic dye molecule or a polymer material containing the same, (3) Fluorescent semiconductors such as porous semiconductors and semiconductor fine particles are known.

  In these phosphors, the fluorescence intensity increases as more functional species (fluorescent functional species) such as fluorescent elements, molecules, and particles are contained in the phosphor, but the functional species approach each other as the concentration increases. As a result, there is a problem that the fluorescence intensity is saturated due to the concentration quenching phenomenon. In order to solve such a problem, an important issue is how to uniformly disperse the fluorescent functional species in the holding matrix.

  In addition, since phosphors are exposed to atmospheres such as gases and liquids and various temperatures during use, there is a risk that the performance of fluorescent functional species will deteriorate due to chemical and thermal influences and contamination exerted from these areas. is there. In order to suppress the deterioration of the fluorescent function due to such external factors, it is an important means to enclose the fluorescent functional species in the holding matrix. In particular, uniformly dispersing fluorescent functional species in a transparent inorganic material such as thermally and chemically stable glass is expected to be an effective means for solving these problems.

  Since rare earth elements and transition metal elements have their fluorescent function in atoms and ions, they are mixed with inorganic crystals and glass raw materials with high chemical durability and melted into transparent inorganic substances such as glass. It is possible to disperse. However, since organic fluorescent dyes and fluorescent semiconductors generally have low thermal and chemical durability, the method of melting together with a glass raw material decreases the fluorescent performance and obtains a material having excellent fluorescent performance. I can't.

As a method of dispersing an organic fluorescent dye or the like in a glass matrix, a method of confining the organic fluorescent dye in a dry glass gel using a sol-gel method has been reported (for example, see Non-Patent Document 1 below). Although this method is expected to improve the stability to some extent, the glass gel obtained by the sol-gel method has nanometer-order pores, so that the chemical action from the outside is sufficiently effective. It cannot be prevented. Although it is possible to make the glass gel transparent by virtue of the method of heat-treating the glass gel, it is difficult to make the glass gel transparent while maintaining the fluorescent function because the organic fluorescent dye is weak against heat.
MMESeverin-Vantilt and EWJL Oomen, Journal of Non-Crystalline Solids 159 (1993) 38-48

  The present invention has been made in view of the above-mentioned problems of the prior art, and its main purpose is to provide a fluorescent material having relatively low thermal and chemical durability, such as organic fluorescent dyes and semiconductor fine particles. It is an object of the present invention to provide a method capable of stably dispersing in a glass matrix without deteriorating the fluorescence function.

The present inventor has intensively studied to achieve the above-described object. As a result, fluorescent materials such as organic fluorescent materials and semiconductor fine particles are mixed with nano-sized glass fine particles and pressurized at a high pressure, so that the fluorescent materials can be stabilized in the glass without degrading the performance of the fluorescent materials. The resulting material has excellent fluorescence performance, and improved chemical durability, heat resistance, etc., and can exhibit fluorescence performance stably for a long period of time. I found. Furthermore, it has been found that by heat-treating the material obtained by this method, the stress strain of the glass material is relieved and the fluorescence characteristics are improved, and the present invention has been completed here.

That is, this invention provides the following fluorescent material, its manufacturing method, and its use. 1. A phosphor glass material characterized by pressurizing a mixture of at least one fluorescent substance selected from the group consisting of organic fluorescent dyes and fluorescent semiconductor fine particles and glass fine particles having a maximum particle size of 100 nm or less at a pressure of 1 GPa or more. Manufacturing method.
2. Item 2. The method for producing a phosphor glass material according to Item 1, wherein 0.0001 to 10 parts by weight of the phosphor is used with respect to 100 parts by weight of the glass fine particles.
3. Item 3. The method for producing a phosphor glass material according to Item 1 or 2, wherein the maximum particle size of the phosphor is 4 times or less than the maximum particle size of the glass particles.
4). Item 4. The method for producing a phosphor glass material according to any one of Items 1 to 3, wherein the glass fine particles are silicate glass, borosilicate glass, or aluminosilicate glass.
5). After manufacturing fluorescent substance glass material by the method in any one of said items 1-4, it heat-processes at the temperature of 50 degreeC or more further, The manufacturing method of fluorescent substance glass material characterized by the above-mentioned.
6). A phosphor glass material obtained by dispersing in a glass matrix at least one phosphor selected from the group consisting of organic fluorescent dyes and fluorescent semiconductor fine particles, obtained by the method according to any one of Items 1 to 5.
7). A display element comprising the phosphor glass material according to Item 6.
8). An illumination element comprising the phosphor glass material according to Item 6.
9. A recording medium comprising the phosphor glass material according to Item 6.

  In the present invention, at least one fluorescent material selected from the group consisting of organic fluorescent dyes and fluorescent semiconductor fine particles and glass fine particles are used as raw materials.

  The type of the organic fluorescent dye is not particularly limited, and may be appropriately selected from substances known as organic dyes having a fluorescence function according to the target color tone.

  Specific examples of such organic fluorescent dyes include coumarin dyes (such as Coumarin 2/307/343 / C343), xanthene dyes (such as Rhodamnie B / 6G), and hemicyanine dyes (PS, LPS, QS, LQS), polyene dyes, benzoxazine dyes, merocyanine dyes, porphyrin dyes, cyanine dyes (flavonoid anthocyanin dyes), azo dyes (Congo red), and the like. An organic fluorescent dye can be used individually by 1 type or in mixture of 2 or more types.

The fluorescent semiconductor fine particles may be appropriately selected from known semiconductor fine particles having fluorescent performance. Specific examples of such semiconductor fine particles include Si semiconductor fine particles; Ge semiconductor fine particles; II-VI group semiconductor fine particles such as CdSe and ZnSe; and III-V group semiconductor fine particles such as InP and GaAs doped with rare earth such as Er. The thing etc. can be mentioned. Semiconductor fine particles can also be used singly or in combination of two or more.

  The particle size of the fluorescent material is not particularly limited, but in order to sufficiently surround the periphery of the fluorescent material with glass fine particles, the maximum particle size of the fluorescent material is about 4 times or less than the maximum particle size of the glass fine particles to be used. It is preferable that Usually, a fluorescent material having a maximum particle size of about 400 nm or less may be used. Further, the minimum particle diameter of the fluorescent substance is not particularly limited, and may be in a single molecule state.

  For glass fine particles, the larger the particle size, the larger the space between the particles in the glass matrix and the amount of fluorescent material that can be held in the glass increases. There is a shortage of the shielding effect against the above, and the mechanical strength tends to decrease. For this reason, glass particles having a maximum particle size of about 100 nm or less are used. For non-spherical glass fine particles, the length of the longest side may be about 100 nm or less. In particular, the particle size of the glass particles is preferably about 50 nm or less, and more preferably about 20 nm or less.

  The minimum diameter of the glass fine particles is not particularly limited, but usually a glass having a particle diameter of about 1 nm or more may be used.

  There are no particular limitations on the type of glass particles, and the material may be appropriately determined according to the environment in which the phosphor glass material is used. For example, silicate glass, borosilicate, aluminosilicate glass, germanate glass, phosphate glass, borate glass, zirconium fluoride glass, aluminum fluoride glass, and the like can be used. Of these, silicate glass, borosilicate, aluminosilicate glass, and the like are particularly preferable in terms of high chemical durability, thermal stability, and the like. Among these, about silicate glass, what contains 50 mol% or more of silicon dioxide is preferable. For example, fumed silica synthesized by a vapor phase method is pure silica fine particles having a particle size of about 10 nm and can be suitably used.

  The mixing ratio of the fluorescent substance and the glass fine particles is not particularly limited, and may be appropriately determined according to the target light emission amount, the physical properties of the glass material, and the like. Usually, the fluorescent material may be about 10 parts by weight or less with respect to 100 parts by weight of the glass fine particles. When the amount of the fluorescent substance exceeds 10 parts by weight, the contact portion between the glass fine particles is reduced, and the mechanical strength, the shielding effect, and the like may be insufficient.

  The lower limit of the amount of the fluorescent substance used cannot be determined unconditionally because it depends on the light emission efficiency, light emission intensity, type of glass fine particles, and the like of the light emitting substance to be used. Since it may be possible to obtain appropriate light emission with an addition amount of about 0.0001 parts by weight relative to parts by weight, this may be the above content. Usually, it is preferable that the luminescent material is about 0.01 parts by weight or more with respect to 100 parts by weight of the glass fine particles.

  In the production method of the present invention, first, a mixture comprising the above-described luminescent material and glass fine particles is prepared. The method for preparing the mixture is not particularly limited. For example, the fluorescent material and the glass fine particles are each pulverized to an appropriate size, if necessary, and then mixed sufficiently; A method of dispersing and adhering a substance on glass fine particles; a method of putting a fluorescent substance and glass fine particles in a solvent that dissolves the fluorescent substance, sufficiently stirring, drying again, and depositing the fluorescent substance on the glass fine particles Can be adopted.

  Next, a target phosphor glass material can be obtained by forming a mixture of a fluorescent substance and glass fine particles into a required shape and then applying pressure. About a pressure, in order to produce the coupling | bonding of glass microparticles, it is necessary to set it as about 1 GPa or more. In particular, in order to sufficiently bond the glass particles to improve transparency and mechanical strength, it is preferable to pressurize at a pressure of about 2 GPa or more. The upper limit of the pressure is not particularly limited, but if the pressure is excessive, cracks or the like may occur in the formed composite material. Therefore, it is usually preferable to set the pressure to about 10 GPa or less.

  There is no particular limitation on the pressurizing method, and any method can be used as long as the mixture of the fluorescent substance and the glass fine particles can be pressurized with a pressure of 1 GPa or more. For example, opposed ultra-high pressure generators such as piston cylinder type, bridgeman type, belt type, diamond anvil cell, multi-anvil type high pressure generator with high pressure isotropy, pressurizer using gas pressure such as HIP, A dynamic high pressure generator such as a railgun can be used.

  The pressurization time may be a time during which the particles can be sufficiently bonded to achieve the target mechanical strength, transparency, and the like. The specific time varies depending on the kind of glass fine particles to be used, the pressurizing method, the pressure, and the like, but is usually about 1 minute or more, and preferably about 10 minutes or more. However, when a dynamic high pressure generator such as a railgun is used, the generated pressure is generally much higher than that of the static pressure generating method, so that sufficient strength can be obtained even when the time is less than 1 minute. May be obtained.

  The temperature at the time of pressurization is not particularly limited, and usually a phosphor glass material having sufficient strength can be obtained by pressurizing at a high pressure of 1 GPa or more at room temperature.

There is no limitation on the atmosphere at the time of pressurization, and usually the treatment may be performed in the air. HIP
When using a pressure device such as gas pressure, gas may enter during pressurization and impair transparency, so take measures such as preventing gas from entering by encapsulating the raw material in a capsule. It is preferable to apply.

  Note that the phosphor glass material obtained by the above-described method may emit fluorescence having a wavelength different from that of the fluorescent material used as a raw material, depending on the pressure during production and other conditions. For this reason, it is easy to obtain a phosphor glass material having light emission of a target color tone by obtaining a shift tendency of the fluorescence wavelength in advance according to the kind of fluorescent substance to be used, the kind of glass fine particles, the production conditions, etc. Can get to.

  According to the method for producing a phosphor glass material of the present invention, the fluorescence performance can be further improved by performing a heat treatment on the phosphor glass material obtained by the above-described method. This is because heat distortion reduces stress strain caused by pressure treatment, reduces stress applied to the fluorescent material, and further suppresses changes in fluorescent performance due to the glass particles approaching the fluorescent material. This is thought to be due to

  In order to achieve the above-described purpose of stress relaxation, the heat treatment temperature is usually about 50 ° C. or higher. In order to obtain a sufficient stress relaxation effect in a shorter time, the heat treatment temperature is preferably about 70 ° C. or higher, and more preferably about 100 ° C. or higher.

The upper limit of the heat treatment temperature is not particularly limited, but may be a temperature lower than the temperature at which the fluorescent substance is decomposed or the characteristics are deteriorated depending on the type of the fluorescent substance dispersed in the glass material. For example, when an organic dye such as rhodamine 6G or coumarin 307 is used as the fluorescent material, the upper limit is about 450 ° C.

  There is no limitation on the atmosphere during the heat treatment, and since the fluorescent material is completely shielded inside the glass, there is no reaction with the fluorescent material even in the presence of oxygen such as in the air.

  The pressure at the time of heat treatment may be a pressure lower than the pressure at the time of pressurization for the purpose of relieving the stress at the time of pressurization, and usually the heat treatment may be performed at atmospheric pressure.

Although there is no limitation in particular also about heating time, processing time can be shortened, so that processing temperature is high. For example, in the case of rhodamine 6G, one hour or more is required at 50 ° C, but 100 ° C
Above, it is sufficient to continue heating for about 10 minutes.

  Even when heat treatment is performed, a phosphor glass material having light emission of a target color tone can be easily obtained by obtaining a wavelength shift and a change in fluorescence intensity due to the heat treatment. In particular, when heat treatment is performed, compared to the case where only pressurization is performed, in general, wavelength shift and decrease in fluorescence intensity are reduced, so that a phosphor material having the desired fluorescence performance can be obtained more easily. Can do.

  According to the method for producing a phosphor glass material of the present invention, it is possible to uniformly disperse a fluorescent substance in a glass matrix by performing pressure molding at a high pressure, such as organic fluorescent dyes, fluorescent semiconductor fine particles, etc. Even a relatively low heat resistance fluorescent material can be encapsulated in a glass matrix without deteriorating the fluorescent performance.

  In addition, by performing heat treatment at a relatively low temperature that does not cause changes in the properties of the fluorescent material, the fluorescent material has better fluorescent performance by suppressing changes in fluorescent performance due to stress on the fluorescent material and the approach of glass particles. A glass material can be obtained.

  Since the phosphor glass material obtained in this way is obtained by pressurizing at a high pressure, the phosphor is stably dispersed in the glass matrix, and the phosphor is surrounded by glass particles. The glass material surface has excellent chemical durability even in an environment where the surface of the glass material is in contact with various chemical substances such as acids, alkalis, and organic solvents. Further, since the fluorescent material does not come into direct contact with oxygen, it is hardly deteriorated even at high temperatures and the heat resistance is very good. Furthermore, the material obtained by performing the heat treatment exhibits more excellent fluorescence characteristics and also has good thermal stability. For this reason, the phosphor glass material obtained by the method of the present invention can exhibit excellent fluorescence performance with long-term stability as a material excellent in chemical and thermal durability.

  The phosphor glass material obtained by the method of the present invention can be used as, for example, a display element, a lighting element, a recording medium, and the like using such excellent characteristics.

The specific method of use in each of these applications is the same as that of conventional phosphors. For example, in applications as display elements, the phosphor glass material obtained by the method of the present invention is pulverized and patterned on a flat substrate. Light-emitting of a so-called organic electroluminescence (EL) display, which emits light when energized by placing a phosphor between narrow electrodes of a transparent conductive film. It can be used as a part or the like. Also, in use as a lighting element, the phosphor glass material powder obtained by the method of the present invention is coated on a substrate surface and used as a lighting element by exciting and emitting light by ultraviolet rays generated by discharge of a fluorescent tube or the like. it can. In addition, for use as a recording medium, it can be used as a recording medium for CD-R, DVD-R, etc., and it can also be used as a thermoluminescent material by utilizing the phenomenon of emitting light when heat is applied to the fluorescent material that has received radiation It is also possible.

  In any of these applications, by using the phosphor glass material obtained by the method of the present invention, chemical durability can be improved and performance excellent in thermal stability can be exhibited.

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

Example 1
6 ml of rhodamine 6G, a xanthene dye, in 100 ml of methanol
g was added and dissolved by stirring. In the obtained solution, 600 mg of fumed silica having a particle size of 10 nm or less (average particle size of about 7 nm) was added and sufficiently stirred.

Next, this liquid was dried at about 50 ° C. to obtain a raw material powder (1 wt% Rhodamine 6G-added silica powder).

  Curve 3 in FIG. 1 is a fluorescence spectrum (excitation wavelength: 346 nm) of the raw material powder, and curve 4 is a fluorescence spectrum (excitation wavelength: 347 nm) of a methanol solution in which a dye is dissolved. In the fluorescence spectrum of the raw material powder, a peak position is recognized at substantially the same wavelength as the methanol solution. From this result, in the raw material powder obtained by drying, the dye molecules are hardly associated, and the particle diameter of the dye is estimated to be about 1 nm or less.

Next, the raw material powder was put in a mold having a diameter of 5 mm, and pressed into a cylindrical pellet having a diameter of 5 mm and a length of about 8 mm by pressing with a pressure of about 1 ton. The processed pellets were placed in a boron nitride sample cell having a thickness of 1 mm, and then pressurized to 8 GPa using an ultrahigh pressure generator using pyrophyllite as a pressure medium. The pressure was increased over 3 hours. After maintaining the pressure at 8 GPa for 1 hour, the pressure was reduced to atmospheric pressure over 5 hours. These compression processes were performed at room temperature to obtain a transparent red glassy object.

  The excitation spectrum (fluorescence wavelength: 630 nm) and fluorescence spectrum (excitation wavelength: 380 nm) of the obtained object are shown as curve 1 and curve 2 in FIG. In the transparent phosphor glass material obtained by compression, it is recognized that the peak position of the fluorescent band is shifted to the longer wavelength side as compared with the fluorescence spectrum of the dry powder (curve 3 in FIG. 1).

Example 2
In 100 ml of methanol, 5 mg of coumarin pigment Coumarin 307 was added and dissolved by stirring. Into the solution, 500 mg of fumed silica having a particle size of 10 nm or less (average particle size of about 7 nm) was added and sufficiently stirred.

Next, this liquid was dried at about 50 ° C. to obtain a raw material powder (1 wt% Coumarin 307 added silica powder). Curve 3 in FIG. 2 is a fluorescence spectrum (excitation wavelength: 410 nm) of the raw material powder, and curve 4 is a fluorescence spectrum (excitation wavelength: 411 nm) of a methanol solution in which a dye is dissolved. In the fluorescence spectrum of the raw material powder, a peak position was observed at almost the same wavelength as the methanol solution. From this result, in the raw material powder obtained by drying, the dye molecules are hardly associated, and the particle diameter of the dye is estimated to be about 1 nm or less.

Next, the raw material powder was put into a mold having a diameter of 5 mm and pressed into a cylindrical pellet having a diameter of 5 mm and a length of about 8 mm by pressing with a pressure of 1 ton. The processed pellets are placed in a boron nitride sample cell with a thickness of 1 mm, and then 8 GPa using an ultrahigh pressure generator using pyrophyllite as a pressure medium.
Until pressurized. The pressure was increased over 3 hours. After maintaining the pressure at 8 GPa for 1 hour, the pressure was reduced to atmospheric pressure over 5 hours. These compression processes were performed at room temperature to obtain a transparent brown glassy object.

  The excitation spectrum (fluorescence wavelength: 584 nm) and fluorescence spectrum (excitation wavelength: 515 nm) of the obtained object are shown as curve 1 and curve 2 in FIG. In the transparent phosphor glass material obtained by compression, it is recognized that the peak position of the fluorescent band is shifted to the longer wavelength side as compared with the fluorescence spectrum of the dry powder (curve 3 in FIG. 2).

Example 3
In 100 ml of methanol, 30 mg of rhodamine 6G (Rhodamine 6G) was added and dissolved by stirring. Into the obtained solution, 600 mg of fumed silica having a particle size of 10 nm or less (average particle size of about 7 nm) was added and sufficiently stirred.

  Next, this solution was dried at a temperature of about 50 ° C. to obtain a raw material powder (5 wt% Rhodamine 6G added silica powder).

When the fluorescence spectrum of Rhodamine 6G in the starting material was measured, it was almost the same as the fluorescence spectrum of methanol in which the dye was dissolved. From this result, in the raw material powder obtained by drying, the dye molecules are hardly associated, and the particle diameter of the dye is estimated to be about 1 nm or less.

Next, the raw material powder was put in a mold having a diameter of 5 mm, and pressed into a cylindrical pellet having a diameter of 5 mm and a length of about 8 mm by pressing with a pressure of about 1 ton. The processed pellets were placed in a boron nitride sample cell having a thickness of 1 mm, and then pressurized to 8 GPa using an ultrahigh pressure generator using pyrophyllite as a pressure medium. The pressure was increased over 3 hours. After maintaining the pressure at 8 GPa for 1 hour, the pressure was reduced to atmospheric pressure over 5 hours. These compression processes were performed at room temperature to obtain a slightly transparent dark red glassy object.

  The obtained glass material is a stable glass material having fluorescence, in which rhodamine 6G, which is an organic fluorescent dye, is enclosed in a transparent glass.

Example 4
In the same manner as in Example 1, a raw material powder containing rhodamine 6G and fumed silica was obtained.

Next, the raw material powder was put in a mold having a diameter of 5 mm, and pressed into a cylindrical pellet having a diameter of 5 mm and a length of about 8 mm by pressing with a pressure of about 1 ton. The processed pellets were placed in a boron nitride sample cell having a thickness of 1 mm, and then pressurized to 2 GPa using an ultrahigh pressure generator using pyrophyllite as a pressure medium. The pressure was increased over 30 minutes, and after maintaining the pressure at 2 GPa for 1 hour, the pressure was reduced to atmospheric pressure over 1 hour. These compression processes were performed at room temperature to obtain a transparent red glassy object.

  The excitation spectrum (fluorescence wavelength: 627 nm) and fluorescence spectrum (excitation wavelength: 379 nm) of the obtained object are shown as curve 1 and curve 2 in FIG. 3, respectively. In the transparent glass phosphor obtained by compression, the peak position of the fluorescent band was shifted to the longer wavelength side compared to the fluorescence spectrum of the dry powder.

Example 5
In 40 ml of toluene, 300 mg of fumed silica having a particle size of 10 nm or less (average particle size of about 7 nm) was added and sufficiently stirred. 0.625 mg of CdSe having a particle size of 3 nm or less (average particle size of 2.7 nm), which is a compound semiconductor fine particle, was added to the obtained solution and dispersed by stirring.

  Next, this liquid was dried at room temperature to obtain a raw material powder (0.21 wt% CdSe-added silica powder).

  Curve 3 in FIG. 4 is a fluorescence spectrum (excitation wavelength: 390 nm) of the dried raw material powder, and curve 4 is a fluorescence spectrum (excitation wavelength: 390 nm) of a toluene solution in which a semiconductor is dispersed. In the fluorescence spectrum of the raw material powder, a peak position was recognized in the same wavelength range as that of the toluene solution.

Next, the raw material powder was put in a mold having a diameter of 5 mm, and pressed into a cylindrical pellet having a diameter of 5 mm and a length of about 8 mm by pressing with a pressure of about 1 ton. The processed pellets were placed in a boron nitride sample cell having a thickness of 1 mm, and then pressurized to 8 GPa using an ultrahigh pressure generator using pyrophyllite as a pressure medium. The pressure was increased over 3 hours. After maintaining the pressure at 8 GPa for 1 hour, the pressure was reduced to atmospheric pressure over 5 hours. These compression processes were performed at room temperature to obtain a brown transparent glassy object.

  The excitation spectrum (fluorescence wavelength: 480 nm) and fluorescence spectrum (excitation wavelength: 380 nm) of the obtained object are shown as curve 1 and curve 2 in FIG. 4, respectively. In the transparent phosphor glass material obtained by compression, the peak position of the fluorescent band is closer to the short wavelength side than the fluorescence spectrum in the dry powder or toluene solution (curve 3 and curve 4 in FIG. 4). A slight shift is recognized.

Dye elution test The dye elution test was performed on the phosphor glass material encapsulating rhodamine 6G obtained in Example 1 by the following method.

  First, 2 mg of the phosphor glass material obtained in Example 1 was weighed and put into an optical cell (1 cm × 1 cm × 4 cm) for fluorescence measurement. 2.6 g of pure methanol was injected into this and sealed. The fluorescence spectrum of methanol was measured 84 days after the addition, and the elution amount of the dye was calculated.

  In ordinary fluorescence measurement, the signal intensity was so weak that it could not be discriminated. Therefore, the fluorescence spectrum of the slightly eluted dye could be observed by reducing the measurement error by repeated measurement 36 times.

From the intensity of the fluorescence spectrum of a methanol reference solution to which 2 × 10 ⁻³ wt% of rhodamine 6G was added, it was found that about 0.01% or less of the total amount of dye in the glass phosphor was eluted in methanol.

  In addition, the said nonpatent literature 1 shows the result of having enclosed the pigment | dye in the dry glass gel using the sol-gel method, However, The pigment | dye elution amount reported here is at least several%. Therefore, it can be said that the amount of elution from the glass phosphor obtained by the method of the present invention is one hundredth of that, and hardly elutes. This dye elution amount corresponds to the amount of dye existing in the vicinity of the surface, so it is considered that there was no elution from the inside.

Heat Resistance Test 10 mg of the phosphor glass material encapsulating rhodamine 6G obtained in Example 1 was placed on a platinum dish and placed in a tubular furnace heated to a predetermined temperature.

  After 6 hours, the phosphor was removed from the furnace and returned to room temperature, and then the fluorescence spectrum was measured. When the temperature was increased from 50 ° C. every 50 ° C. and the same heat treatment / fluorescence spectrum measurement was repeated, the fluorescence function was maintained until heating at 450 ° C. for 6 hours.

  In contrast, the raw material powder was blackened by oxidation at about 250 ° C. and the fluorescence function was lost. From these results, it is considered that in the phosphor glass material of the present invention, the phosphor is encapsulated in the glass, whereby the reaction with external oxygen can be suppressed, and thus the heat resistance is improved.

Example 6
The transparent phosphor glass material obtained by the compression treatment in the same manner as in Example 1 was put into an electric furnace in an air atmosphere preheated to 50 ° C. and subjected to heat treatment for 6 hours.

Curve 1 in FIG. 5 is a fluorescence spectrum (excitation wavelength: about 590 nm) of a phosphor glass material that has been heat-treated at 50 ° C. Compared with curve 2 in FIG. 1 showing the fluorescence spectrum of the phosphor glass material obtained by compression treatment in Example 1, it was confirmed that the peak position of the fluorescence spectrum slightly shifted to the short wavelength side by heat treatment at 50 ° C. did it.

  After the above heat treatment at 50 ° C., heat treatment at 100 ° C. for 6 hours, heat treatment at 200 ° C. for 6 hours, heat treatment at 300 ° C. for 6 hours, heat treatment at 350 ° C. for 6 hours, and heat treatment at 400 ° C. for 6 hours Heat treatment for 4 hours was continued at 450 ° C. for 6 hours.

Curve 2 in FIG. 5 is the fluorescence spectrum of the phosphor glass material after heat treatment at 100 ° C. (excitation wavelength: about 560 nm), and curve 3 is the fluorescence spectrum of the phosphor glass material after heat treatment at 200 ° C. (excitation wavelength: about 530 nm). ), Curve 4 is the fluorescence spectrum of the phosphor glass material after heat treatment at 300 ° C. (excitation wavelength: about 530 nm), and curve 5 is the fluorescence spectrum of the phosphor glass material after heat treatment at 350 ° C. (excitation wavelength: about 530 nm). ), Curve 6 is the fluorescence spectrum of the phosphor glass material after heat treatment at 400 ° C. (excitation wavelength: about 530 nm), and curve 7 is the fluorescence spectrum of the phosphor glass material after heat treatment at 450 ° C. (excitation wavelength: about 530 nm).
).

  As is apparent from curve 2 in FIG. 5, by performing the heat treatment at 100 ° C., a larger shift of the peak position of the fluorescence spectrum to the short wavelength side occurred, and an increase in fluorescence intensity could be confirmed. Furthermore, up to a heat treatment temperature of 350 ° C., the fluorescence intensity increased monotonously and shifted to the short wavelength side. Although it was confirmed that the heat intensity at 400 ° C. and 450 ° C. decreased the fluorescence intensity, the fluorescence intensity was still larger than the sample not subjected to the heat treatment.

Example 7
In 100 ml of methanol, 5 mg of coumarin pigment Coumarin 47 was added and stirred to dissolve. Into the solution, 500 mg of fumed silica having a particle size of 10 nm or less (average particle size of about 7 nm) was added and sufficiently stirred.

  Subsequently, this liquid was dried at about 50 ° C. to obtain a raw material powder (1 wt% Coumarin 47-added silica powder). Curve 4 in FIG. 6 is the fluorescence spectrum of the raw material powder, and curve 3 is the fluorescence spectrum of the methanol solution in which the dye is dissolved. In the fluorescence spectrum of the raw material powder, a peak position was observed at almost the same wavelength as the methanol solution. From this result, in the raw material powder obtained by drying, the dye molecules are hardly associated, and the particle diameter of the dye is estimated to be about 1 nm or less.

Next, the raw material powder was put into a mold having a diameter of 5 mm and pressed into a cylindrical pellet having a diameter of 5 mm and a length of about 8 mm by pressing with a pressure of 1 ton. The processed pellets are placed in a boron nitride sample cell with a thickness of 1 mm, and then 8 GPa using an ultrahigh pressure generator using pyrophyllite as a pressure medium.
Until pressurized. The pressure was increased over 3 hours. After maintaining the pressure at 8 GPa for 1 hour, the pressure was reduced to atmospheric pressure over 5 hours. These compression processes were performed at room temperature to obtain a transparent brown glassy object.

  The excitation spectrum (fluorescence wavelength 470 nm) and fluorescence spectrum (excitation wavelength 400 nm) of the obtained object are shown as curve 1 and curve 2 in FIG. In the transparent phosphor glass material obtained by compression, it is recognized that the peak position of the fluorescent band is shifted to the longer wavelength side as compared with the fluorescence spectrum of the dry powder (curve 4 in FIG. 6).

The phosphor glass material after compression was put into an electric furnace in an air atmosphere preheated to 100 ° C. and subjected to heat treatment for 6 hours.

  Curve 1 in FIG. 7 is the fluorescence spectrum (excitation wavelength 400 nm) of the phosphor glass material that has not been heat-treated, and curve 2 is the fluorescence spectrum (excitation wavelength 400 nm) of the phosphor glass material after the heat treatment. As is clear from the comparison of the two curves, in the phosphor glass after the heat treatment, the fluorescence intensity increases and the peak position shifts to a short wavelength.

  After heat treatment at 100 ° C., heat treatment was further performed at 200 ° C. for 6 hours, 300 ° C. for 6 hours, and 400 ° C. for 6 hours.

Curve 3 in FIG. 7 shows the fluorescence spectrum of the phosphor glass after heat treatment at 200 ° C. (excitation wavelength 400).
nm), curve 4 is the fluorescence spectrum (excitation wavelength 390 nm) of the phosphor glass after heat treatment at 300 ° C., and curve 5 is the fluorescence spectrum (excitation wavelength 360 nm) of the phosphor glass after heat treatment at 400 ° C. .

  As is clear from FIG. 7, the heat intensity up to 200 ° C. was followed by a monotonous increase in fluorescence intensity and a short wavelength shift. The heat intensity at 300 ° C. and 400 ° C. decreased the fluorescence intensity, and the fluorescence intensity was lower than that of the sample not subjected to heat treatment. From this result, it is surmised that the effect of heat treatment has occurred on the fluorescence performance of the fluorescent material, but since a shift to the short wavelength side close to the fluorescence spectrum of the dried powder of Coumarin 47 was observed, phosphor glass material It is considered that the effect of stress relaxation on is produced.

Example 8
About the glass fluorescent substance obtained by the method similar to Example 5, it put into the electric furnace of the air atmosphere pre-heated at 200 degreeC, and heat-processed for 6 hours.

Curve 1 in FIG. 8 is a fluorescence spectrum (excitation wavelength 380 nm) of the phosphor glass material not subjected to heat treatment, and curve 2 is a fluorescence spectrum (excitation wavelength 455 nm) of the phosphor glass material after heat treatment at 200 ° C. is there. As is clear from the comparison between the two curves, in the phosphor glass material after the heat treatment, the fluorescence intensity increased, and a shift of the peak position toward the long wavelength side close to the peak position of the dry powder of CdSe was observed.

  After heat treatment at 200 ° C., heat treatment was further performed at 300 ° C. for 6 hours and then at 400 ° C. for 6 hours.

Curve 3 in FIG. 8 shows the fluorescence spectrum of the phosphor glass after heat treatment at 300 ° C. (excitation wavelength 450).
nm), curve 4 is the fluorescence spectrum of the phosphor glass that was subsequently heat treated at 400 ° C. (excitation wavelength 450 nm).

  As is clear from FIG. 8, in the heat treatment at 300 ° C. and 400 ° C., a shift of the peak position toward the short wavelength side was observed as compared with the heat-treated product at 200 ° C. In comparison, it was in a state shifted to the long wavelength side close to the peak position of the dry powder of CdSe. In addition, an increase in fluorescence intensity was observed with an increase in the heat treatment temperature.

The drawing which shows the fluorescence spectrum and excitation spectrum about the fluorescent substance glass material obtained in Example 1, and its raw material. The drawing which shows the fluorescence spectrum and excitation spectrum about the fluorescent substance glass material obtained in Example 2, and its raw material. The figure which shows the fluorescence spectrum about the fluorescent substance glass material obtained in Example 4, and an excitation spectrum. The drawing which shows the fluorescence spectrum and excitation spectrum about the fluorescent substance glass material obtained in Example 5, and its raw material. The drawing which shows a fluorescence spectrum about the fluorescent substance glass material of various heat processing temperature obtained in Example 6. FIG. Drawing which shows the fluorescence spectrum and excitation spectrum about the fluorescent substance glass material after pressure molding in Example 7, and its raw material. The drawing which shows a fluorescence spectrum about the fluorescent substance glass material of various heat processing temperature obtained in Example 7. FIG. The drawing which shows a fluorescence spectrum about the fluorescent substance glass material of various heat processing temperature obtained in Example 8. FIG.

Claims (8)

A phosphor glass material was manufactured by pressing a mixture of at least one fluorescent substance selected from the group consisting of organic fluorescent dyes and fluorescent semiconductor fine particles and glass fine particles having a maximum particle size of 100 nm or less at a pressure of 1 GPa or more . Then, the manufacturing method of the phosphor glass material characterized by further heat-processing at the temperature of 50 degreeC or more . The manufacturing method of the fluorescent substance glass material of Claim 1 which uses 0.0001-10 weight part of fluorescent substances with respect to 100 weight part of glass fine particles. The method for producing a phosphor glass material according to claim 1 or 2, wherein the maximum particle size of the fluorescent material is 4 times or less than the maximum particle size of the glass fine particles. The method for producing a phosphor glass material according to any one of claims 1 to 3, wherein the glass fine particles are silicate glass, borosilicate glass, or aluminosilicate glass. Obtained by the method of any of claims 1-4, phosphor glass material at least one kind of fluorescent material selected from the group consisting of organic fluorescent dyes and fluorescent semiconductor fine particles are dispersed in a glass matrix. A display element comprising the phosphor glass material according to claim 5 . An illumination element comprising the phosphor glass material according to claim 5 . A recording medium comprising the phosphor glass material according to claim 5 .

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