JP2006077153A - Phosphor production method and production apparatus, and phosphor particles and precursors thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a phosphor production method capable of producing phosphor fine particles containing a plurality of metal components constituting a crystal matrix and an activator with a nanometer level fine structure with a simple structure.
A raw material gas flow ET containing a metal constituting a crystal matrix and a metal constituting an activator and a reaction gas flow GR covering the raw material gas flow ET are caused to flow into a reaction space HK in a high-temperature atmosphere, and the raw material Fine particles are formed by heat treatment at the outer periphery of the gas flow ET, and the fine particles are cooled by the reaction gas flow GR to generate phosphor particles or phosphor particle precursors. When the precursor is generated, the phosphor particles are obtained by firing.
[Selection] Figure 3

Description

  The present invention relates to a method for producing a phosphor in which an activator is present in a crystal matrix, a production apparatus used for the method for producing the phosphor, and a phosphor produced by the method for producing a phosphor.

  The phosphor is used as a light-emitting element such as a plasma display. However, the phosphor is conventionally produced by a solid phase method, a liquid phase method, a spray pyrolysis method, a hydrothermal synthesis method, a gas phase. Various methods such as the method are used.

Among the above methods, the solid phase method is a method in which raw material powders are mixed, heated under high temperature conditions and fired (solid phase reaction), and then finely pulverized with a ball mill or the like to produce phosphor particles.
The liquid phase method generates phosphor particles using a liquid phase reaction such as a coprecipitation method, a crystallization method, or a sol-gel method. The spray pyrolysis method sprays the raw material solution into droplets. After that, it is heated by burning a burner or the like, and phosphor particles are generated by evaporation and thermal decomposition of the solvent (see Patent Document 2).
The vapor phase method uses a gas phase reaction to generate phosphor particles, and rapidly heats and cools the phosphor material suspended in a carrier gas through a heating area with a heat source such as plasma. There are a method for producing phosphor particles (see Patent Document 1) and a method for producing phosphor particles by introducing a vapor component of the phosphor material heated and vaporized into a reactor such as an electric furnace to cause thermal decomposition. Yes (see Patent Documents 3 and 4).

JP 7-292354 A JP 2003-342563 A JP 2004-168641 A JP 2004-210949A

  Among conventional phosphor production methods, solid-phase methods using solid-phase reactions and spray pyrolysis methods using spray combustion with a burner, etc., produce phosphor particles with fine structures on the nanometer level. However, it is possible to produce phosphor particles having a fine structure by the liquid phase method. However, in any of the solid phase method, the liquid phase method, and the spray pyrolysis method, there is a disadvantage that the raw material preparation step and the particle preparation step for the solid phase reaction and the liquid phase reaction are complicated.

  On the other hand, in the vapor phase method, it is possible to produce phosphor particles having a fine structure, but in the method described in Patent Document 1, cooling is performed because the raw material is cooled simply by going out of the heating region. In the methods described in Patent Documents 3 and 4, since the raw material needs to be led to each part such as a vaporizer and a reactor, there is a disadvantage that the particle preparation process becomes complicated.

  The present invention has been made in view of the above circumstances, and its purpose is to produce phosphor particles containing a plurality of metal components constituting a crystal matrix and an activator with a nanometer-level fine structure with a simple configuration. It is an object of the present invention to provide a phosphor manufacturing method, a phosphor manufacturing apparatus suitable for the manufacturing method, a phosphor particle manufactured by the phosphor manufacturing method, and a precursor thereof.

  The first characteristic configuration of the phosphor manufacturing method according to the present invention for achieving the above object is to cover a raw material gas flow containing a metal constituting a crystal matrix and a metal constituting an activator, and the raw material gas flow. The reaction gas flow is caused to flow into a reaction space in a high-temperature atmosphere, and fine particles are formed by heat treatment at the outer periphery of the raw material gas flow, and the fine particles are cooled by the reaction gas flow to phosphor particles or phosphor particle precursors The point is to generate the body.

That is, when the raw material gas flow containing the metal constituting the crystal matrix and the metal constituting the activator and the reaction gas flow covering the raw material gas flow are caused to flow into the reaction space of the high temperature atmosphere, the reaction gas flow was covered. The raw material gas flow is heat-treated at the outer periphery of the raw material gas flow to generate fine particle nuclei composed of the crystal matrix and each metal component of the activator, but the generated core particles are moved by the reaction gas flow when moving with the reaction gas flow. Because of rapid cooling, coalescence / aggregation of generated particles and condensation / reaction of vapor to the particle surface are sufficiently suppressed. As a result, small particle size fluorescence consisting of each metal component of the crystal matrix and activator A precursor of body particles or phosphor particles is obtained.
Furthermore, the raw material gas stream containing the metal components of the crystal matrix and the activator is covered with the reaction gas stream and flows into the reaction space in a high-temperature atmosphere, and undergoes many steps (processes). Therefore, a phosphor particle having a small particle size or a precursor of the phosphor particle composed of each metal component of the crystal matrix and the activator can be easily produced.
Accordingly, there is provided a method for producing a phosphor capable of producing phosphor particles containing a plurality of metal component particles constituting a crystal matrix and an activator with a nanometer level fine structure with a simple structure.

The second characteristic configuration is that a phosphor particle is produced by firing the phosphor particle precursor.
That is, when the fine particles generated in the method for producing the phosphor having the first characteristic configuration are phosphor particle precursors, the phosphor particles are obtained by firing the phosphor particle precursor.
Accordingly, there is provided a phosphor manufacturing method for manufacturing phosphor particles from a precursor of phosphor particles containing a plurality of metal component particles constituting a crystal matrix and an activator in a nanometer level fine structure.

  The third characteristic configuration is that the heat treatment is based on a chemical reaction between the raw material gas flow and the reaction gas flow.

That is, the raw material gas flow is heat-treated by the heat generated by the chemical reaction between the raw material gas flow and the reaction gas flow to generate fine particle nuclei composed of the metal components of the crystal matrix and the activator, and the generated core particles are reacted. Phosphor particles or phosphor particle precursors are generated while cooling with a gas flow and suppressing coalescence / aggregation, condensation / reaction of vapor onto the particle surface, and the like.
Therefore, a chemical reaction between the raw material gas stream and the reactive gas stream, for example, heat treatment of the raw material gas stream using heat generated by burning the raw material gas stream containing hydrocarbons with the reactive gas stream composed of oxygen gas. It can be done efficiently.

  The fourth characteristic configuration is that the reaction gas flow is composed of an oxygen-containing gas, and the crystal matrix is formed as a metal oxide.

That is, the metal component of the crystal matrix in the raw material gas stream reacts with the oxygen-containing gas constituting the reaction gas stream to generate phosphor particles or phosphor particle precursors in which the crystal matrix is formed as a metal oxide. The
Therefore, the crystal matrix is formed as a metal oxide, and phosphor particles having excellent stability or precursors thereof can be obtained.

  The characteristic configuration of the phosphor manufacturing apparatus according to the present invention is used in the method according to any one of the first to fourth characteristic configurations, and includes a metal constituting the crystal matrix and a metal constituting the activator. A liquid nozzle that ejects a raw material liquid to be ejected, and a gas nozzle that is located around the liquid nozzle and ejects a gas that forms a reaction gas flow along the axial direction of the liquid nozzle. .

That is, a liquid that contains a metal that constitutes the crystal matrix and a metal that constitutes the activator is ejected from the liquid nozzle, and a gas that forms a reaction gas flow is formed from the gas nozzle located around the liquid nozzle. When ejected along the core direction, the raw material liquid ejected from the liquid nozzle is atomized by the gas ejected from the gas nozzle into a droplet flow, and this droplet flow rises in temperature in the reaction space of the high-temperature atmosphere. As the vapor pressure rises, it evaporates and changes to a raw material gas flow, and a raw material gas flow and a reaction gas flow covering the raw material gas flow are formed.
Here, the liquid ejection is stable, and it is easy to set the ratio of the amount of each metal supplied in the raw material liquid. Even in the case of a precursor, the production reaction can be accurately controlled to obtain phosphor particles comprising a desired proportion of metal components or precursors thereof.
Therefore, while appropriately setting the supply amount of each metal using a raw material liquid containing a plurality of metals as the raw material of the phosphor particles, it is possible to appropriately form a raw material gas flow covered with a reactive gas flow, Provided is a production apparatus suitable for producing phosphor particles comprising a metal component having a complicated composition ratio or a precursor thereof.

The first characteristic configuration of the phosphor particles or the precursor thereof according to the present invention is manufactured by the method of any one of the first to fourth characteristic configurations, the average particle diameter is in the range of 10 nm to 5000 nm, and The specific surface area is in the range of 1 to 100 m ² / g.

That is, phosphor particles having a small particle diameter and a large specific surface area increase the amount of ultraviolet absorption, which contributes to improving the luminance of the phosphor.
Therefore, by limiting the average particle diameter and specific surface area to the above ranges, a highly useful phosphor for exciting ultraviolet rays is provided.

The second characteristic configuration of the phosphor particles according to the present invention is manufactured by the method having any one of the first to fourth characteristic configurations and has an excitation wavelength in the range of 100 nm to 400 nm.
That is, a phosphor having an excitation wavelength in the range of 100 nm to 400 nm can be used for various display devices using ultraviolet light as an excitation source.
Therefore, by limiting the excitation wavelength to the above range, a highly useful phosphor for ultraviolet excitation is provided.

Embodiments of a phosphor manufacturing method and manufacturing apparatus according to the present invention, and phosphor particles and precursors manufactured by the method will be described below with reference to the drawings.
FIG. 1 shows the configuration of the main part of a particle production system used for producing the phosphor particles of the present invention. The particle production system includes a reactor 10 as a fine particle production apparatus, a recovery device 20 that cools and collects fine particles generated in the reactor 10, and the like. Although not shown, the fine particles emitted from the reactor 10 pass through the cooling tower and are cooled, and then collected by a collection device such as a bag filter, a cyclone, an electrostatic precipitator, or a scrubber provided in the collection unit 20.

  The pressure in the reactor 10 is reduced or increased by an exhaust device provided on the downstream side of the recovery device 20. Here, although not shown, as an exhaust device, specifically, an exhaust fan and a damper are provided in the exhaust passage, and the internal pressure of the reactor 10 is maintained at a constant pressure (for example, reduced to about −10 kPa). In addition, based on the measurement information of the pressure sensor that measures the internal pressure of the reactor 10, the number of rotations of the fan motor that drives the exhaust fan is inverter-controlled, or the opening degree of the damper is changed and adjusted. By maintaining the internal pressure of the reactor 10 at a constant pressure in this way, the flow rate of the reaction gas flow GR described later is stabilized, and the size (particle size) of the generated phosphor particles and their precursor particles is stabilized. Is obtained. Further, in order to maintain the internal pressure of the reactor 10 at a constant pressure, a pressure sensor is installed in equipment such as the piping after the reactor 10 and a cooling tower / collector, and based on the measurement information of the pressure sensor, You may make it perform the rotation speed control of a fan motor, and the opening degree adjustment of a damper.

  The reactor 10 includes a cylindrical container 1 having a tapered particle outlet or a container having a short tube attached to a non-tapered cylinder. A high temperature atmosphere is provided inside the container 1 above the container 1. A plasma generator 2 is installed as a heat source for creating the reaction space HK. The plasma generator 2 is supplied with a discharge argon gas by a supply tube 7. Incidentally, the supply amount of argon gas in the plasma generator 2 is about 50 liters / min, and the plasma output is about 7 kW. The gas supplied to the plasma generator 2 is not limited to argon gas alone, but may be a mixed gas in which helium gas, hydrogen gas or nitrogen gas is added to argon gas, for example, about 20%. That is, since the thermal conductivity differs depending on the type of gas, the plasma temperature can be controlled by changing the composition of the gas supplied to the plasma generator 2.

A single nozzle unit 3 is installed on the inlet 1 side wall of the container 1 with the injection direction directed into the container 1. As shown in FIGS. 2 and 3, the nozzle unit 3 is positioned around the liquid nozzle 4 and a liquid nozzle 4 that ejects a raw material liquid containing a metal constituting the crystal matrix and a metal constituting the activator. And a gas nozzle 5 that ejects a gas (specifically, oxygen gas) that forms the reaction gas flow GR along the axial direction of the liquid nozzle 4. Here, as the raw material liquid containing the metal constituting the crystal matrix and the activator, a metal-containing organic solvent solution such as a metal alkoxide, a metal complex, or an organometallic compound of the metal component is used as described later. The gas nozzle 5 is supplied with oxygen gas from the supply pipe 5a, and the liquid nozzle 4 is supplied with raw material liquid from the supply pipe 4a (see FIG. 1). Incidentally, the supply amount of oxygen gas from the gas nozzle 5 is about 0.3 m ³ / min, and the supply capacity of the raw material liquid from the liquid nozzle 4 is about 100 g / min.

  In addition, arrangement | positioning of the said plasma generator 2 and the nozzle unit 3 with respect to the container 1 is not restricted to the arrangement | positioning shown in FIG. 1, It can set arbitrarily. For example, in FIG. 1, the plasma generator 2 and the nozzle unit 3 may be interchanged, the plasma generator 2 may be installed on the inlet side lateral wall of the container 1, and the nozzle unit 3 may be installed on the top of the container 1.

  The gas nozzle 5 is formed concentrically with the liquid nozzle 4 in the axial direction of the liquid nozzle 4. Specifically, the liquid nozzle 4 is formed in a circular shape, and the gas nozzle 5 is formed in an annular shape around the circular liquid nozzle 4. 2 schematically shows the structure of each of the nozzles 4 and 5. FIG. 2A shows a gas / liquid external mixing type, and FIG. 2B shows a gas / liquid internal mixing type.

  The structure of the nozzle unit 3 is not limited to a structure (FIG. 2) in which flow paths for the liquid nozzle 4 and the gas nozzle 5 are formed in a single member such as a cylindrical shape. For example, a single liquid nozzle is the center. And a nozzle unit in which a plurality of gas nozzles separate from the liquid nozzles are arranged symmetrically around the liquid nozzle.

  Furthermore, although not shown, the fine particle production apparatus of the present invention includes a cooling means for cooling the reaction space HK according to the size of the phosphor particles to be produced and the precursor particles thereof. Specifically, a water cooling jacket is disposed on the outer periphery of the container 1 to cool it from the outside of the container, and a cooling gas (oxygen gas or the like) or liquid (water or the like) is blown into the container 1. Direct cooling means or the like can be used.

  Next, as schematically shown in FIG. 3, the method for producing a phosphor according to the present invention includes a raw material gas flow ET containing a metal constituting a crystal matrix and a metal constituting an activator, and the raw material gas flow. The reaction gas flow GR covering the ET is caused to flow into the reaction space HK in a high-temperature atmosphere, and fine particles are formed by heat treatment at the outer periphery of the raw material gas flow ET. A precursor of phosphor particles is generated. The heat treatment is based on a chemical reaction between the raw material gas flow ET and the reaction gas flow GR. Specifically, the raw material gas stream ET contains hydrocarbons, the reaction gas stream GR is composed of an oxygen-containing gas, and the hydrocarbons in the raw material gas stream ET are burned with the oxygen-containing gas to generate heat, and the raw material A metal component in the gas stream ET is oxidized to generate a metal oxide, and a phosphor particle or a phosphor particle precursor in which a crystal matrix containing an activator in the crystal is formed as a metal oxide is generated.

  In the present embodiment, the reaction space HK in a high-temperature atmosphere in a state where the droplet flow ET containing the phosphor particle raw material (a plurality of types of metals constituting the crystal matrix and the activator) is positioned inside the reaction gas flow GR. The raw material gas stream ET is made by being ejected into the interior and vaporized. That is, when the ejected droplet flow ET travels in the reaction space HK, it evaporates and vaporizes as the temperature rises and changes to a raw material gas flow ET. Accordingly, the left base side of the flow portion represented by ET is a droplet flow region, and the right tip side is a raw material gas flow region. In FIG. 3, reference numeral 3 denotes the nozzle unit that forms the droplet flow (raw material gas flow) ET and the reaction gas flow GR. By this nozzle unit 3, the cone spreading angle θg of the reaction gas flow GR is changed to the droplet flow. (Raw material gas flow) It is formed to be larger than the spread angle θe of the cone of ET.

Next, the production mechanism of the phosphor particles of the present invention or precursor particles thereof will be described.
(1) The phosphor particles and the precursor particles thereof are reaction regions (combustion zone) HR generated in the outer peripheral portion of the raw material gas flow ET (specifically, near the interface of the reactive gas flow GR in contact with the raw material gas flow ET). Is generated.
(2) The generated particles in the reaction region HR move at a speed equivalent to the moving speed of the reaction gas flow GR.
(3) When the amount of reaction gas injected from the nozzle unit 3 is reduced to lower the moving speed of the reaction gas flow GR, the high temperature area due to heat propagation from the reaction space HK widens and the reaction region HR moves toward the nozzle unit 3 side. Approach (state of FIG. 3 (C)). As a result, the residence time in which the generated particles stay in the reaction region HR (the time during which the particles are kept in a high temperature atmosphere) is lengthened, the heat treatment proceeds at a high temperature, and the cooling action is also reduced due to the reduced speed of the reaction gas flow GR. Since it becomes weak, coalescence of the generated particles is promoted, and the particle diameter increases.
(4) Conversely, when the amount of reaction gas injected from the nozzle unit 3 is increased to increase the moving speed of the reaction gas flow GR, the expansion of the high temperature area due to heat propagation from the reaction space HK is suppressed, and the reaction region HR Becomes far from the nozzle 3 side (state shown in FIG. 3B). As a result, the residence time in which the generated particles stay in the reaction region HR (the time during which the particles are kept in the high temperature atmosphere) is shortened, so that the heat treatment at high temperature does not proceed so much. Since it becomes strong, coalescence of particles is suppressed and the particle size is reduced.

Accordingly, by changing the ratio of the flow rate of the reaction gas flow GR to the flow rate of the raw material gas flow (actually a droplet flow) ET (hereinafter referred to as a gas-liquid ratio), the size of the phosphor particles or their precursor particles is changed. Can be adjusted.
That is, when the gas-liquid ratio is large, the flow rate of the reaction gas flow GR increases and the thickness of the gas layer increases, and the amount of ambient gas that absorbs the heat of the generated particles increases. As a result, the cooling effect on the generated particles is increased, the reaction region HR is shortened, and the residence time of the generated particles in the reaction region HR is shortened. The diameter becomes smaller.
On the other hand, when the gas-liquid ratio is small, the flow rate of the reaction gas flow GR decreases and the thickness of the gas layer decreases, and the amount of surrounding gas that absorbs the heat of the generated particles decreases. As a result, the cooling effect on the generated particles is reduced, the reaction region HR becomes longer, and the residence time of the generated particles in the reaction region HR becomes longer. The particle diameter increases.

Furthermore, in the method for manufacturing a phosphor according to the present invention, when the precursor particle of the phosphor particle is generated by the fine particle manufacturing apparatus, the phosphor particle precursor is fired to generate the phosphor particle. . Specifically, the precursor of the phosphor particles recovered by the recovery device 20 is baked under a temperature condition of 500 to 1600 ° C. in a reducing or air atmosphere using a heating furnace (not shown), and the baked product is obtained. The product is pulverized (pulverized) with a wet or dry ball mill. Incidentally, at the time of firing, if necessary, as a sintering-preventing agent and flux (flux), the addition of such AlF ₃ and MgF _2. Moreover, you may add Al, In, Si, Sn, Ti, Zn, Zr etc. as a surface coating agent.

Next, specific examples of the raw material materials for phosphor fine particles according to the present invention will be listed and described below.
First, various metal oxides are used as the crystal matrix.
CeMgAl ₁₁ O ₁₉ , GdMgB ₅ O ₁₀ , BaMgAl ₁₀ O ₁₇ , BaAl ₁₂ O ₁₉ , Sr ₄ Al ₁₄ O ₂₅ , (Ba, Sr) (Mg, Mn) Al ₁₀ O ₁₇ , YAlO ₃ , Y ₂ O ₃ , Y ₃ Al ₅ O ₁₂ , Y ₂ SiO ₅ , Zn ₂ SiO ₄ , SnO ₂ , (Ba, Sr, Mg) O.xAl ₂ O ₃ , YVO ₄ , (Ba, Mg) Al ₁₆ O ₂₇ , Ca ₂ Y ₈ (SiO ₄ ) ₆ O ₂ , YAlO ₃ , (Ba, Mg) ₂ SiO ₄ , LiY ₉ (SiO ₄ ) ₆ O ₂ , Zn ₂ GeO ₄ , BaMgAl ₁₄ O ₂₃ , Ba ₂ Mg ₂ Al ₁₂ O ₂₂ , Ba ₂ Mg ₄ Al ₁₈ O ₁₈ , Ba ₃ Mg ₅ Al ₁₈ O ₃₅ , (Ba, Sr, Ca) (Mg, Zn, Mn) Al ₁₀ O ₁₇ , Ba (Y, Ce) ₂ SiAl ₄ O ₁₂ , Ba (Y, Eu) ₂ SiAl ₄ O ₁₂ , Sr (Y, Ce) ₂ SiAl ₄ O ₁₂ , Mg (Y, Ce) ₂ SiAl ₄ O ₁₂ , 0. 7 (Ba (Y, Ce) ₂ SiAl ₄ O ₁₂ ) · 0.3 ((Y, Ce) ₃ Al ₅ O ₁₂ ), Ba (Y, Ce, Pr) ₂ SiAl ₄ O ₁₂ , (Ba, Mg) (Y, Ce) ₂ SiAl ₄ O ₁₂ , 0.3 (Mg (Y, Ce) ₂ SiAl ₄ O ₁₂ ) · 0.7 ((Y, Ce) ₃ Al ₅ O ₁₂ )

The following rare earth metal ions and metal ions are used as the activator or coactivator to be doped into the crystal matrix.
(Rare earth metal ions) Ce, Dy, Er, Eu, Gd, Ho, Nd, Pm, Pr, Sm, Tb, Tm, Yb, Lu
(Metal ion) Al, Ag, Mn, Sb, Sn

And the fluorescent substance of each color is comprised combining the said crystal | crystallization base | substrate and an activator (co-activator).
(Red phosphor) Y ₂ O ₃ : Eu, YVO ₄ : Eu, (Ba, Mg) Al ₁₆ O ₂₇ : Eu, Ca ₂ Y ₈ (SiO ₄ ) ₆ O ₂ : Eu, YAlO ₃ : Eu, (Ba , Mg) ₂ SiO ₄ : Eu, LiY ₉ (SiO ₄ ) ₆ O ₂ : Eu, BaY ₂ SiAl ₄ O ₁₂ : Eu

(Green _{phosphor) Y 2 SiO 5: Ce,} Tb, Zn 2 GeO 4: Mn, BaAl 12 O 19: Mn, Ba 2 SiO 4: Eu, (Ba, Mg) Al 16 O 27: Eu, Mn, Zr ₂ SiO ₄ , MgAl ₁₁ O ₁₉ : Ce, Tb, Sr ₄ Al ₁₄ O ₂₅ : Eu, Zn ₂ SiO ₄ : Mn, CeMgAl ₁₁ O ₁₉ : Tb, (Ba, Mg) ₂ SiO ₄ : Eu, (Sr, _{Ba) Al 2 Si 2 O 3} : Eu, BaY 2 Si (Al, Ga) 4 O 12: Ce, BaY 2 SiAl 4 O 12: Ce, BaY 2 SiAl 4 O 12: Tb, 0.3BaY 2 SiAl 4 O _{12 · 0.7Y 3 Al 5 O 12} : Ce, SrY 2 SiAl 4 O 12: Ce

(Blue _{phosphor) CaWO 4, CaWO 4: W} , BaMgAl 14 O 23: Sm, (Ba, Sr) (Mg, Mn) Al 10 O 17: Eu, BaMgAl 10 O 17: Eu, Tb, Sm, Sr 4 Al ₁₄ O ₂₅ : Eu, Y ₂ SiO ₅ : Ce, Ba ₂ Mg ₂ Al ₁₂ O ₂₂ : Eu, BaMgAl ₁₄ O ₂₃ : Eu, Ba ₂ Mg ₄ Al ₈ O ₁₈ : Eu, Ba ₃ Mg ₅ Al ₁₈ O ₃₅ : Eu, (Ba, Sr, Ca) (Mg, Zn, Mn) Al ₁₀ O ₁₇ : Eu, CaMgSi ₂ O ₆ : Eu

And the organometallic compound (metal complex etc.) of each metal which comprises the said crystal | crystallization base | substrate and an activator is used as a raw material liquid in the state diluted with the solvent. Hereinafter, organometallic compound names are exemplified.
Al: Aluminum mono-n-butoxydiethyl acetoacetate or ethyl acetoacetate aluminum dinormal butyrate, and mixtures thereof Ba: Barium 2-ethylhexanoate Ca: Calcium 2-ethylhexanoate Ce: 2-ethyl Cerium hexanoate Li: Lithium naphthenate Mg: Magnesium 2-ethylhexanoate Mn: Manganese 2-ethylhexanoate Si: Octamethylcyclotetrasiloxane or polydimethylsiloxane, and mixtures thereof Sm: 2-ethylhexanoic acid Samarium Sn: Tin 2-ethylhexanoate Sr: Strontium 2-ethylhexanoate Y: Yttrium 2-ethylhexanoate Zn: Zinc 2-ethylhexanoate Eu: Eurobi 2-ethylhexanoate Um V: vanadium naphthenate or vanadium 2-ethylhexanoate and mixtures thereof Tb: terbium 2-ethylhexanoate Ge: germanium 2-ethylhexanoate Zr: zirconium 2-ethylhexanoate W: metatungstic acid Ammonium Gd: Gadolinium 2-ethylhexanoate Dy: Dysprosium 2-ethylhexanoate Er: Erbium 2-ethylhexanoate Ho: Holmium 2-ethylhexanoate Nd: Neodymium 2-ethylhexanoate Pm: Promethium 2-ethylhexanoate Pr : Praseodymium 2-ethylhexanoate Tm: thulium 2-ethylhexanoate Yb: ytterbium 2-ethylhexanoate Ag: silver neodecanoate Sb: antimony 2-ethylhexanoate

The following can be used as a dilution solvent.
1) Mineral spirit, 2) Mineral thinner, 3) Petroleum spirit, 4) White spirit, 5) Mineral turpentine, 6) Kerosene, 7) N-hexane, 8) Hexanoic acid, 9) 2-ethylhexane Acid, 10) cyclohexane, 11) isoheptane, 12) ethanol, 13) methanol, 14) 1-propanol, 15) acetic acid, 16) 1-pentanol, 17) valeric acid, 18) toluene, 19) isopropyl alcohol, 20 ) N-propyl alcohol, 21) isobutyl alcohol, 22) n-butyl alcohol, 23) benzene, 24) xylene

[Another embodiment]
In the above embodiment, oxygen gas is used as a gas for forming the reaction gas flow GR, a chemical reaction (oxidation reaction) is caused as a heat treatment, heat is generated by combustion, and phosphor particles made of a metal oxide or its Although the precursor particles are generated, it is also possible to generate phosphor particles made of nitride or precursor particles thereof by causing a nitriding reaction using nitrogen gas instead of oxygen gas. Further, as the heat treatment, a reaction other than a chemical reaction may be used.

  In the above embodiment, after the raw material liquid containing the metal constituting the crystal matrix and the metal constituting the activator is ejected from the liquid nozzle 4 to generate the droplet stream ET, the droplet stream ET is evaporated and evaporated. Although the raw material gas flow ET is formed, a raw material gas prepared in advance in a state containing a plurality of kinds of metals constituting the crystal matrix and the activator is ejected from the gas nozzle to form the raw material gas flow ET. May be.

Next, as an example, _{two materials of} Zn ₂ SiO ₄ : Mn (Example 1) which is a green phosphor and BaMgAl ₁₀ O ₁₇ : Eu (Example 2) which is a blue phosphor will be described as examples. .

Particles shown in FIG. 1 are prepared by mixing and mixing zinc 2-ethylhexanoate, octamethylcyclotetrasiloxane, manganese 2-ethylhexanoate, and mineral spirit in a predetermined molar ratio as a raw material liquid. Particles made of Zn ₂ SiO ₄ : Mn were produced by a production system.

FIG. 4 shows a TEM photograph of the prepared Zn ₂ SiO ₄ : Mn before firing, and FIG. 5 shows a TEM photograph after firing at 1000 ° C. for 2 hours. I understand that. From FIG. 4, it can be seen that the particle diameter before firing is somewhat varied and distributed in the range of 15 to 75 nm.

Also, FIG. 6 is a graph of X-ray diffraction results of before firing, and fired for 2 hours at each temperature condition of 600 ° C., 800 ° C., 1000 ° C., and 1200 ° C. The data of the specific surface area (m ² / g) and the corresponding firing temperatures of 800 ° C., 1000 ° C., and 1200 ° C. are shown. The value of the specific surface area is in the range of 6 to 24 m ² / g. From FIG. 6, in the phosphor particles of this material, the crystal state is not clear in the unfired state and the firing temperature of 600 ° C., and the crystal state clearly appears at the firing temperature of 800 ° C. or higher. This while at the firing temperature of the unfired state and 600 ° C. is a value the value of comparable specific surface area (m 2 ^{/ g),} at the firing temperature above 800 ° C. The ratio specific surface area (m 2 ^/ g This is supported by the fact that the value of) decreases and the crystallization by firing proceeds. Accordingly, when Zn ₂ SiO ₄ : Mn is not fired, a precursor of phosphor particles is generated, and the precursor particles are fired at a temperature range of 800 ° C. to 1200 ° C. to produce phosphor particles. I understand.

As raw materials, predetermined moles of barium 2-ethylhexanoate, magnesium 2-ethylhexanoate, aluminum mono-n-butoxydiethylacetoacetate, ethylacetoacetate aluminum dinormal butyrate, europium 2-ethylhexanoate, and mineral spirits Particles composed of BaMgAl ₁₀ O ₁₇ : Eu were produced by the particle production system shown in FIG.

FIG. 7 shows a TEM photograph of the produced BaMgAl ₁₀ O ₁₇ : Eu before firing, and FIG. 8 shows a TEM photograph after firing at 1200 ° C. for 2 hours. I understand that. The crystal form of this material is hexagonal, and two large hexagonal crystals can be confirmed in the photograph after firing. From FIG. 7, it can be seen that the particle size before firing is relatively small and distributed within a range of 50 nm or less.

FIG. 9 is a graph of the X-ray diffraction results of the sample before firing and after firing for 2 hours at each temperature condition of 800 ° C., 1000 ° C., and 1200 ° C. Data corresponding to each firing temperature of 1200 ° C.) and specific surface area (m ² / g). The specific surface area is a relatively large value of 23 to 46 m ² / g, which indicates that the particles are minute. From FIG. 9, in the phosphor particles of the present material, even in an unfired state, the crystal state clearly appears to the same extent as in the case of the firing temperatures of 800 ° C. and 1000 ° C. This is because the specific surface area (m ² / g) is the same in the unfired state and those at the firing temperatures of 800 ° C. and 1000 ° C., whereas the specific surface area is at the firing temperature of 1200 ° C. This is supported by the fact that the value of (m ² / g) becomes small. Therefore, it can be seen that BaMgAl ₁₀ O ₁₇ : Eu produces phosphor particles even in an unfired state. However, by firing at 1200 ° C., the crystal state becomes clearer and the characteristics as a phosphor are improved.

Conventionally, BaMgAl ₁₀ O ₁₇ : Eu phosphors usually have to be fired at a high temperature of about 1600 ° C. In the method of the present invention, phosphors having desired characteristics can be obtained by firing at a low temperature of about 1200 ° C. Particles are obtained. Such low-temperature firing is preferable from the viewpoint of reducing temperature variation in the furnace and the like, reducing the thermal distortion of the fired product, and saving energy, but the reason why such low-temperature firing is possible First, BaMgAl ₁₀ O ₁₇ : Eu phosphor particles produced by the method of the present invention have a particle size as small as a nanometer level, so that heat conduction is fast and firing efficiency is good. 2, it is considered that a crystal state has already appeared before firing and crystal formation proceeds rapidly using this as a seed.

As shown in the application examples below, the phosphor particles according to the present invention can be applied to various uses other than the display device in addition to the use of the display device material.
(1) It can be used as an inorganic oxide phosphor of an image display device such as PDP (plasma display panel), CRT (cathode ray tube), FED (field emission display), electroluminescence device, active light-emitting type liquid crystal device.
(2) It can be used as an inorganic oxide phosphor for printing inks such as laser printers, ink jets, transfer ribbons and offset printing.
(3) It can be used as an inorganic oxide phosphor for a color material such as an electrophotographic toner, an electronic recording medium, a paint, and a writing instrument.
(4) It can be used as an inorganic oxide phosphor for photographic materials such as intensifying screens and silver halide photographic materials.

Sectional drawing which shows the whole structure of the fluorescent substance fine particle manufacturing apparatus which concerns on this invention Sectional view and front view schematically showing the structure of the nozzle part The figure which illustrates typically the production | generation process of the fluorescent substance fine particle concerning this invention Electron micrograph before firing of phosphor fine particles of Example 1 Electron micrograph after firing of the phosphor fine particles of Example 1 The figure which shows the data of the fluorescent substance fine particle of Example 1 Electron micrograph before firing of phosphor fine particles of Example 2 Electron micrograph after firing of the phosphor fine particles of Example 2 The figure which shows the data of the fluorescent substance fine particle of Example 2

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Container 2 Plasma generator 3 Nozzle unit 4 Liquid nozzle 4a Supply pipe 5 Gas nozzle 5a Supply pipe 7 Supply pipe 10 Reactor (microparticle production apparatus)
20 Collector ET Raw material gas flow (droplet flow)
GR reaction gas flow HK reaction space HR reaction region

Claims (7)

  A raw material gas flow containing a metal constituting the crystal matrix and a metal constituting the activator and a reaction gas flow covering the raw material gas flow are caused to flow into a reaction space in a high temperature atmosphere, and heat treatment is performed on the outer periphery of the raw material gas flow. A method for producing a phosphor, in which fine particles are formed by the method, and the fine particles are cooled by the reaction gas flow to produce phosphor particles or phosphor particle precursors.   The phosphor manufacturing method according to claim 1, wherein the phosphor particles are produced by firing the precursor of the phosphor particles.   The method for producing a phosphor according to claim 1 or 2, wherein the heat treatment is performed by a chemical reaction between the raw material gas flow and the reaction gas flow.   The method for producing a phosphor according to any one of claims 1 to 3, wherein the reaction gas flow is composed of an oxygen-containing gas, and the crystal matrix is formed as a metal oxide. It is a manufacturing apparatus of the fluorescent substance used for the method of any one of Claims 1-4,
A liquid nozzle that ejects a raw material liquid containing a metal that constitutes the crystal matrix and a metal that constitutes the activator, and a gas that forms a reaction gas flow around the liquid nozzle, in the axial direction of the liquid nozzle And a gas nozzle that ejects along the line. A phosphor particle or fluorescence produced by the method according to any one of claims 1 to 4, having an average particle diameter in the range of 10 nm to 5000 nm and a specific surface area in the range of 1 to 100 m ² / g. Precursor of body particles. A phosphor particle produced by the method according to claim 1 and having an excitation wavelength in the range of 100 nm to 400 nm.