KR101419858B1 - Phosphor, and preparing method of the same - Google Patents

Abstract

Obtaining a mixed solution comprising an alkaline earth metal salt, a rare earth metal salt, a Group 3 metal salt, and an oxide precursor of an excessive Group 4 element; And a method of adding a cellulose to the mixed solution followed by heat treatment, and a phosphor produced by the method.

Description

FIELD OF THE INVENTION [0001] The present invention relates to phosphors,

The present invention provides a process for producing a mixed solution comprising an alkaline earth metal salt, a rare earth metal salt, a Group 3 metal salt, and an oxide precursor of an excess Group 4 element; And a method of adding a cellulose to the mixed solution followed by heat treatment, and a phosphor produced by the method.

Since the first light-emitting diodes (LEDs) were developed in the 1960s, light-emitting diode technology has evolved significantly. The light emitting diode is a candidate material that has attracted attention as a next-generation solid state lighting material in that it has higher energy efficiency, longer lifetime, better environment friendliness and reliability than conventional light sources. However, in order for the light emitting diode to maintain a high emission efficiency and stability at a high temperature, there is a problem that the phosphor, which is a main component of the light emitting diode, has had in the past, namely, the decrease in the light emitting property during the operation of the light emitting diode and the thermal quenching I needed to be.

Meanwhile, conventional phosphors are generally manufactured using a solid state reaction method (SSR). However, the precursor of the phosphor obtained by the hand-grinding of the oxide raw material using the solid-phase method has a problem in that the uniformity is inferior.

On the other hand, a phosphor containing a rare earth metal has a characteristic that its luminescence and intensity are different depending on the electrons of the rare earth metal. For example, Eu ^{3 +} 4f → 4f is only due to the energy potential difference indicate a sharp light emission of a small region, Eu ^{+ 2} is due to the 5d → 4f energy potential difference it shows the emission of a large area. The electron quantity of the rare earth metal can be controlled through oxidation or reduction. For example, conventionally, as a method of controlling electrons through reduction of the rare earth metal, a method of removing oxygen and firing in an atmosphere containing hydrogen is used. However, such a method has a problem that the degree of reduction is insufficient and the emission intensity of the phosphor obtained as a result is not uniform.

When it is possible to produce a phosphor having stable light emission and uniform light emission intensity by an easy and economical method, the obtained phosphor may be a light emitting diode (LED), a plasma display panel (PDP) A field emission display (FED), and a cold cathode fluorescent lamp (CCFL). For example, Korean Patent No. 10-1053884 entitled " Composition for forming a phosphor layer, a plasma display panel and a method for manufacturing the plasma display panel "discloses that a phosphor can be usefully used for a PDP.

The inventors of the present invention have completed the present invention by discovering that, when a phosphor is produced according to the method of the present invention, a phosphor having stable luminescence and uniform luminescence intensity can be produced by an easy and economical method.

Accordingly, the present invention provides a mixed solution comprising an alkaline earth metal salt, a rare earth metal salt, a Group 3 metal salt, and an oxide precursor of an excess Group 4 element; And a method of preparing a phosphor by adding cellulose to the mixed solution and then heat-treating the phosphor, and a phosphor prepared by the method.

However, the problems to be solved by the present invention are not limited to the above-mentioned problems, and other matters not mentioned can be clearly understood by those skilled in the art from the following description.

A first aspect of the present invention is directed to a process for preparing a mixed solution comprising an alkaline earth metal salt, a rare earth metal salt, a Group 3 metal salt, and an oxide precursor of an excess of a Group 4 element; And a step of adding cellulose to the mixed solution and then heat-treating the mixed solution.

According to a second aspect of the present invention, there is provided a phosphor produced by the method according to the first aspect of the present invention, wherein the phosphor has a composition of [M ¹ -M ² ₂ M ³ ₂ O ₈ : M ⁴ + xA] ¹ is an alkaline earth metal, M ² is a Group 3 metal, M ³ is a Group 4 element, M ⁴ is a rare earth metal ion, A is an oxide of M ³ , Phosphor, and phosphor.

According to the present invention, a phosphor having stable light emission and uniform light emission intensity can be produced by an easy and economical method.

Specifically, when a phosphor is manufactured using a liquid phase precursor method (LPP) instead of the conventional solid phase method according to the present invention, a process of impregnating the uniformly mixed solution into the cellulose is included, It is possible to obtain uniformly distributed phosphors of uniformly distributed single crystals. Accordingly, the phosphor of the present invention exhibits excellent luminous efficiency, has a round shape, and can be used in various fields such as white LED or CCFL. In addition, when the phosphor is manufactured according to the present invention, since it can be produced at a relatively low temperature in a short time, it is advantageous in productivity and economy.

On the other hand, the fluorescent substance containing a rare earth metal has a feature that its luminescence and intensity are changed according to the electrons of the rare earth metal. When the electron of the rare earth metal can be controlled, the luminescence is stable, A phosphor can be produced easily and economically. For example, a rare earth metal-based metal ion is widely used divalent europium ion (Eu ^{+ 2)} is an active agent (Activator) in the phosphor, 4f ⁶ 5d ¹ -4f ⁷ Is useful in that it exhibits a broad emission band from the ultraviolet light to the red spectral region resulting from the allowed transition. However, since it exists in Eu ^{3 +} form rather than Eu ^{2 +} form in a general phosphor manufacturing environment, the emission stability and light emission intensity of the phosphor are limited. However, when an excessive amount of an oxide precursor of a Group 4 element, for example, an excess amount of SiO ₂ is added in the process of manufacturing the phosphor according to the method of the present invention, the process of synthesizing the phosphor by the abundant electrons existing at the corner of the SiO ₂ A larger amount of Eu < ^{3 + &gt}; Eu ^< ^{2 + & gt ;} , and thus the photoluminescence (PL) intensity of the phosphor can be greatly improved.

Phosphors which are stable in light emission and uniform in light emission intensity and which are manufactured by an easy and economical method according to the present invention can be used for a light emitting diode (LED), a plasma display panel (PDP), a field emission display (FED), and a cathode fluorescent lamp ) Can be applied in various fields.

1 is a flowchart showing a process of manufacturing a phosphor according to a first aspect of the present invention.
FIG. 2 is a schematic view showing a schematic diagram and a chemical structural formula of cellulose when cellulose is added to a mixed solution in the process of producing a phosphor according to the first aspect of the present invention.
FIG. 3 is a schematic diagram showing a crystal structure of [CaAl ₂ Si ₂ O ₈ : Eu ^{2 +} ] as an example among the phosphors according to the second aspect of the present application.
FIG. 4 shows XRD patterns of phosphors prepared by adding various concentrations of SiO ₂ according to an embodiment of the present invention. Specifically, FIG. 4A shows the XRD patterns of phosphors [CaAl ₂ Si ₂ O ₈ : Eu ²⁺ + xSiO ₂ ], FIG. 4B is an XRD pattern of a phosphor [SrAl ₂ Si ₂ O ₈ : Eu ^{2 +} + xSiO ₂ ], and FIG. 4C is a phosphor [BaAl ₂ Si ₂ O ₈ : Eu ²⁺ + xSiO ₂ ].
FIG. 5 shows a photoluminescence (PL) spectrum of each phosphor prepared by adding various concentrations of SiO ₂ according to an embodiment of the present invention. Specifically, FIG. 5A is a graph showing the emission spectra of phosphors [CaAl ₂ Si ₂ O ₈ : Eu ^{₂ + +} xSiO ^2] of the excitation spectrum (dotted line), a light emitting spectrum (solid line), and the light emission intensity (sapdo) standardized by the wavelength of 430 nm, and FIG. 5b is a phosphor _{[SrAl 2 Si 2 O 8:} Eu 2 ⁺ + xSiO _2] of the excitation spectrum (dotted line) and emission spectrum (solid line), and Figure 5c is a phosphor _{[BaAl 2 Si 2 O 8:} Eu 2 + + xSiO 2] of the excitation spectrum (dotted line) and emission spectrum (solid line) to be.
6 is an optical microscope image of a phosphor [CaAl ₂ Si ₂ O ₈ : Eu ^{2 +} + xSiO ₂ ] prepared by adding various concentrations of SiO ₂ according to an embodiment of the present invention, and FIGS. 6A to 6C Is an image in the case of no UV lamp irradiation, and Figs. 6d to 6f are images in the case of UV lamp irradiation.
FIG. 7 is a graph showing the thermal stability of a phosphor [CaAl ₂ Si ₂ O ₈ : Eu ^{2 +} + xSiO ₂ ] prepared by adding various concentrations of SiO ₂ according to an embodiment of the present invention.
8 shows an FE-SEM image of each of the phosphors prepared by adding SiO ₂ at various concentrations according to an embodiment of the present invention. Specifically, FIGS. 8A to 8D show the phosphors [CaAl ₂ Si ₂ O ₈ : Eu ^{₂ + +} xSiO ^2], Figure 8e to Fig 8i is the phosphor _{[SrAl 2 Si 2 O 8:} Eu 2 + + xSiO 2], Figure 8j through 8m is phosphor _{[BaAl 2 Si 2 O 8:} Eu 2 + + xSiO ₂ ].

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. It should be understood, however, that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In the drawings, the same reference numbers are used throughout the specification to refer to the same or like parts.

Throughout this specification, when a part is referred to as being "connected" to another part, it is not limited to a case where it is "directly connected" but also includes the case where it is "electrically connected" do.

Throughout this specification, when a member is "on " another member, it includes not only when the member is in contact with the other member, but also when there is another member between the two members.

Throughout this specification, when an element is referred to as "including " an element, it is understood that the element may include other elements as well, without departing from the other elements unless specifically stated otherwise. The terms "about "," substantially ", etc. used to the extent that they are used throughout the specification are intended to be taken to mean the approximation of the manufacturing and material tolerances inherent in the stated sense, Accurate or absolute numbers are used to help prevent unauthorized exploitation by unauthorized intruders of the referenced disclosure. The word " step (or step) "or" step "used to the extent that it is used throughout the specification does not mean" step for.

Throughout this specification, the term "combination thereof" included in the expression of the machine form means one or more combinations or combinations selected from the group consisting of the constituents described in the expression of the machine form, And the like.

Hereinafter, embodiments and examples of the present invention will be described in detail with reference to the accompanying drawings.

A first aspect of the present invention is directed to a process for preparing a mixed solution comprising an alkaline earth metal salt, a rare earth metal salt, a Group 3 metal salt, and an oxide precursor of an excess of a Group 4 element; And a step of adding cellulose to the mixed solution and then heat-treating the mixed solution.

For example, the oxide precursor of the Group 4 element required in the basic composition of the phosphor may be about 2 moles, and the "oxide precursor of the excess Group 4 element" contained in the mixed solution of the first aspect of the present invention, May be greater than about 2 moles, but the present disclosure is not limited thereto.

For example, the phosphor prepared according to the first aspect of the present application, including Ca as an alkaline earth metal _{[CaAl 2 Si 2 O 8:} Eu 2 + + xSiO 2] the case, the oxide precursor of the excess of the Group 4 element May be more than about 2 mol required for CaAl ₂ Si ₂ O ₈ , which is a basic composition of the phosphor, but the present invention is not limited thereto. For example, an oxide precursor of the Group 4 element of greater than about 2 mol and less than about 9 mol may be included in the mixed solution, such that x is greater than about 0 and less than about 7, but is not limited thereto.

For example, when the phosphor prepared according to the first aspect of the present invention is [SrAl ₂ Si ₂ O ₈ : Eu ^{2 +} + xSiO ₂ ] containing Sr as an alkaline earth metal, the oxide precursor of the excess Group 4 element is May be more than about 2 mol required for SrAl ₂ Si ₂ O ₈ , which is the basic composition of the phosphor, but the present invention is not limited thereto. For example, an oxide precursor of the Group 4 element of greater than about 2 mol and less than about 5 mol may be included in the mixed solution, such that x is greater than about 0 and less than about 3, but is not limited thereto.

For example, when the phosphor prepared according to the first aspect of the present invention is [BaAl ₂ Si ₂ O ₈ : Eu ^{2 +} + xSiO ₂ ] containing Ba as an alkaline earth metal, the excess oxide precursor of the Group 4 element is May be more than about 2 mol required for BaAl ₂ Si ₂ O ₈ , which is a basic composition of the phosphor, but the present invention is not limited thereto. For example, an oxide precursor of the Group 4 element of greater than about 2 mol and less than about 6 mol may be included in the mixed solution, such that x is greater than about 0 and less than about 4, but is not limited thereto. At this time, if the amount of SiO ₂ added is excessively large, the amount of the phosphor in the product is rather less than the amount of SiO ₂ added, so that the luminescence brightness may be lowered, so the amount of SiO ₂ to be added needs to be appropriately adjusted, The above examples illustrate but are not limited to the appropriate amount of SiO ₂ .

For example, the phosphor may be prepared by dissolving each of the alkaline earth metal salt, the rare earth metal salt, and the Group 3 metal salt in an aqueous solution to prepare an oxide precursor of a liquid Group 4 element in the basic composition of the phosphor, And the mixed solution is impregnated with the cellulose to obtain impregnated material. The impregnated material is heat-treated to remove the impurity-removed phosphor powder. And may be produced in the form of a phosphor having a finally increased surface area and a uniform composition by pulverizing the phosphor powder, but the present invention is not limited thereto.

For example, the phosphor may be prepared by dissolving Ca (NO ₃ ) ₂ .4H ₂ O, Sr (NO ₃ ) ₂ .4H ₂ O, or BaCl ₂ as the alkaline earth metal salt in water to prepare an aqueous solution, EuCl ₃ .3H ₂ O as a metal salt was dissolved in water to prepare an aqueous solution. Al (NO ₃ ) ₃ .9H ₂ O was dissolved in water as the Group 3 metal salt to prepare an aqueous solution. The aqueous solutions were quantitatively mixed Then, an SiO ₂ sol as an oxide precursor of the Group 4 element is further added to the mixture in addition to about 2 moles required in the basic composition of the phosphor, and then a liquid mixture is obtained through liquid-phase agitation, To obtain impregnated material, drying the impregnated material to obtain a shape of xerogel or xerosol, heat-treating the xerogel or xerosol to obtain a spherical fluorescent material , But is not limited thereto.

In this regard, FIG. 1 is a flow chart illustrating a process of manufacturing a phosphor according to a first aspect of the present invention. For example, the method of FIG. 1 may be subdivided into the steps of: 1) obtaining the mixed solution, 2) impregnating the mixed solution with cellulose, 3) calcining the impregnated cellulose, 4) And a reducing step 5, but the present invention is not limited thereto. Hereinafter, Steps 1 to 5 are exemplarily described to facilitate understanding of the first aspect of the present invention, but the present invention is not limited thereto.

First, step 1 of obtaining the mixed solution is a step of dissolving Ca (NO ₃ ) ₂ .4H ₂ O, Sr (NO ₃ ) ₂ .4H ₂ O, or BaCl ₂ as the alkaline earth metal salt in water to prepare an aqueous solution And EuCl ₃ .3H ₂ O as the rare earth metal salt is dissolved in water to prepare an aqueous solution. Al (NO ₃ ) ₃ .9H ₂ O as the Group 3 metal salt is dissolved in water to prepare an aqueous solution. And further adding SiO ₂ sol as an oxide precursor of the above-mentioned group 4 element in addition to about 2 mol required in the basic composition of the phosphor, followed by liquid phase stirring to obtain the mixed solution uniformly mixed But is not limited thereto.

Next, the step 2 of impregnating the mixed solution with cellulose may be to uniformly impregnate the mixed solution into uniformly arranged nano-sized cells of a fiber type having the cellulose, It is not. Since the ion sizes of the metal salts included in the mixed solution are nano-sized, the process of uniformly penetrating the nano-sized cells of the cellulose may be performed spontaneously, but the present invention is not limited thereto. In this regard, FIG. 2 of the present application is a diagrammatic view showing a schematic diagram and a chemical structure of cellulose when cellulose is added to a mixed solution during the process of manufacturing a phosphor according to the first aspect of the present invention, 2 < / RTI >

The step 3 of firing the impregnated cellulose may be carried out by heating the cellulose in which the metal salts of the mixed solution uniformly permeate through the step 2 into an electric heating furnace and heating the cellulose, The reaction may be carried out according to a reaction scheme, but is not limited thereto:

[(C ₆ H ₁₀ O ₆ ) _n → CO ↑ or CO ₂ ↑ + H ₂ O ↑ + O ₂ ↑]

According to the above reaction formula, the cellulose which is a skeleton may be partially or wholly oxidized and removed. At this time, moisture of the mixed solution may be evaporated and metal salts in the mixed solution may be oxidized, but the present invention is not limited thereto. For example, the firing in step 3 may be performed at about 500 ° C for about 3 hours, but is not limited thereto.

Next, step 4, which is calcined at a temperature higher than the step 3, is a step of completely oxidizing and removing the remaining cellulose that has not been removed through the step 3 and removing the metal oxide crystals But is not limited thereto. ≪ tb > < / TABLE > Without such step 4, cellulose may remain, in which case a phosphor powder close to black due to the carbon component of the cellulose is obtained. Since the remnants of the cellulose contained in the phosphor powders act as impurities to lower the brightness of the phosphor, it is possible to improve the brightness of the phosphor by performing the high temperature calcination as in the step 4. However, no.

Next, the reducing step 5 may be performed to obtain a phosphor containing a divalent cation of a rare earth metal, but the present invention is not limited thereto. In the above steps 3 and 4, the rare earth metal used as the activator, for example, Eu, is present as a trivalent cation. When the rare earth metal used as the activator of the phosphor is a trivalent cation, only the 4f-4f electron transition occurs. In this case, the fifth shell, which is the outermost electron shell, hinders the influence of crystals from the outside, Only the red light can be emitted. On the other hand, when the rare earth metal used as the activator of the phosphor is a divalent cation, 4f-5d electron-transfer occurs. In this case, since the electron is converted into the outermost electron shell, Can emit all the light from blue to red depending on the crystal. For this reason, the utility of the rare earth metal used as the activator of the phosphor is high when it is a divalent cation rather than a trivalent cation. However, the rare earth metal in divalent cation form is obtained by firing in a separate reducing atmosphere because the rare earth metal in air is present as Eu ₂ O ₃ in the trivalent cation form. The reducing atmosphere can be formed, for example, by supplying a mixed gas of N ₂ and H ₂ , a mixed gas of inert gas and H ₂ , or a CO gas into the reaction furnace. Upon completion of the reduction treatment in step 5, a phosphor containing divalent cations of a rare earth metal can be obtained, but the present invention is not limited thereto.

According to one embodiment of the present invention, the alkaline earth metal salt may include, but is not limited to, a salt of Ca, Sr, Ba, Mg, or Be. For example, the alkaline earth metal salt may include, but is not limited to, Ca (NO ₃ ) ₂ .4H ₂ O, Sr (NO ₃ ) ₂ .4H ₂ O, or BaCl ₂ . The composition of the phosphor to be produced can be varied by diversifying the kind of the alkaline earth metal salt contained in the mixed solution, but the present invention is not limited thereto. In addition, although the fluorescent characteristics of the phosphor may be affected depending on which element the phosphor contains as the alkaline earth metal, the present invention is not limited thereto.

According to one embodiment of the present invention, the rare earth metal salt may include, but is not limited to, a salt of Eu, La, Ce, Nd, Gd, Tb, Dy, Er, or Yb. For example, the rare earth metal salt may include, but is not limited to, EuCl ₃ .3H ₂ O. The rare earth metal of the rare earth metal salt may act as an activator of the phosphor, but is not limited thereto.

According to one embodiment of the present invention, the Group 3 metal salt may include, but is not limited to, a salt of Al, Ga, or In. For example, the Group 3 metal salt may include Al (NO ₃ ) ₃ .9H ₂ O, but is not limited thereto.

According to one embodiment of the invention, an oxide precursor of the Group 4 element is _{SiO 2, Si (OH) 4} , SiH 4, Si (OC 2 H 5) 4, water soluble silane, GeO _2, Ge (OH) _4, GeH ₄ , Ge (OC ₂ H ₅ ) ₄ , SnO ₂ , Sn (OH) ₄ , SnH ₄ , or Sn (OC ₂ H ₅ ) ₄ . For example, the oxide precursor of the Group 4 element may be, but is not limited to, a water soluble silicate (WSS) or a SiO ₂ sol having a particle size of about 5 nm to about 3000 nm . For example, it is preferable to use SiO ₂ , Si (OH) ₄ , or water-soluble silane as the oxide precursor of the Group 4 element, but the present invention is not limited thereto.

According to one embodiment of the present disclosure, the oxide precursor of the excess Group 4 element may include, but is not limited to, greater than about 2 mol and less than about 20 mol. Here, the oxide precursor of the Group 4 element required for the phosphor composition itself is about 2 moles, but the method of manufacturing the phosphor according to the first aspect of the present invention is not limited to the addition of the oxide precursor of the Group 4 element And a step of obtaining the mixed solution containing an oxide precursor of the group IV element. As described above, in the method for producing a phosphor according to the first aspect of the present invention, an oxide precursor of a Group 4 element exceeding about 2 mol of an oxide precursor of a Group 4 element required for the phosphor composition itself is used, Quot; an oxide precursor of an excess Group 4 element "is used in the first aspect of the present invention. For example, the excess of the oxide precursor of the Group 4 element may include greater than about 2 mol to less than about 5 mol, greater than about 2 mol to less than about 8 mol, less than about 2 mol to less than about 12 mol, Less than about 10 mol, less than about 15 mol, less than about 2 mol, less than about 20 mol, less than about 5 mol, less than about 8 mol, less than about 5 mol, Less than about 20 moles, less than about 8 moles, less than about 12 moles, greater than about 8 moles less than about 15 moles, greater than about 8 moles less than about 20 moles, greater than about 12 moles less than about 15 moles, Less than 20 moles, or greater than about 15 moles to less than about 20 moles. As described above, the brightness of the phosphor produced by adding the oxide precursor of the Group 4 element to the mixed solution in an excessive amount can be increased, but is not limited thereto.

For example, the excessive amount of the oxide precursor of the Group 4 element may vary depending on the composition of the mixed solution used for producing the phosphor, but the present invention is not limited thereto. For example, in preparing a phosphor containing Ca as an alkaline earth metal, it may be preferable that an oxide precursor of the Group 4 element is added in an amount of about 5 moles in addition to about 2 moles for the basic composition of the phosphor, and Sr It is preferable that an oxide precursor of the Group 4 element is added in an amount of about 2 moles in addition to about 2 moles for the basic composition of the phosphor. In the production of a phosphor containing Ba as an alkaline earth metal, It may be preferred that an oxide precursor of the Group 4 element is added in an amount of about 3 moles in addition to about 2 moles for the basic composition of the phosphor, but the present invention is not limited thereto. This is described in more detail with reference to FIGS. 5A to 5C in the following [Embodiment], but the present invention is not limited thereto.

According to one embodiment of the present invention, the mixed solution may be a mixture of the alkaline earth metal salt, the rare earth metal salt, the Group 3 metal salt, and the oxide precursor of the excess Group 4 element, no.

According to one embodiment of the present invention, the cellulose may be selected from the group consisting of cellulose powder, cellulose sheet, spherical cellulose, water-soluble cellulose, pulp, crystallized cellulose, amorphous cellulose, and combinations thereof, But is not limited thereto. For example, it may be desirable, but not limited, to use a high purity pulp having a purity of at least about 99.8% and having a finer matrix morphology.

According to one embodiment of the invention, the heat treatment may comprise a first heat treatment being performed at about 150 ° C to about 600 ° C, and a second heat treatment being performed at about 600 ° C to about 1500 ° C in sequence But is not limited thereto. For example, the primary heat treatment may be performed at a temperature of about 150 캜 to about 300 캜, about 150 캜 to about 450 캜, about 150 캜 to about 600 캜, about 300 캜 to about 450 캜, But is not limited to, at about < RTI ID = 0.0 > 450 C < / RTI > Also, for example, the secondary heat treatment may be performed at a temperature of about 600 캜 to about 800 캜, about 600 캜 to about 1000 캜, about 600 캜 to about 1200 캜, about 600 캜 to about 1500 캜, , About 800 ° C to about 1200 ° C, about 800 ° C to about 1500 ° C, about 1000 ° C to about 1200 ° C, about 1000 ° C to about 1500 ° C, or about 1200 ° C to about 1500 ° C, It is not.

For example, the cellulose may be decomposed through the primary heat treatment, but the present invention is not limited thereto. For example, the decomposition of the cellulose through the primary heat treatment may include decomposition of the cyclic portion included in the cellulose, or decomposition of the -OH group or the -CH ₂ O group portion within the cellulose , But the primary heat treatment may be performed to decompose and remove the impurity ligand, but the present invention is not limited thereto. For example, if the primary heat treatment temperature is less than about 150 ° C, the decomposition of the cellulose may be difficult, but is not limited thereto. On the other hand, when the primary heat treatment temperature is higher than about 600 ° C, the precursor of the phosphor is decomposed and oxidized to form an oxide such as an oxide-based silicate to affect the final phosphor, but the present invention is not limited thereto. The primary heat treatment may be performed without any separate pulverization process, and it may be easy to obtain a uniform phosphor at a lower temperature than in the case of performing the pulverization process, but the present invention is not limited thereto.

For example, the second heat treatment may be performed in an oxygen atmosphere in order to remove residual organic substances from the solid state phosphor precursor powder obtained through the first heat treatment and to crystallize the phosphor precursor powder. However, But is not limited to. At this time, the temperature at which the secondary heat treatment is performed may be appropriately adjusted to easily remove residual organic substances and crystallize the phosphor precursor powder. However, the present invention is not limited thereto. For example, when the second heat treatment is performed at a temperature less than about 600 ° C., the amorphous phosphor precursor powder is difficult to crystallize and a long heat treatment may be required, but the present invention is not limited thereto. On the other hand, when the second heat treatment is performed at a temperature higher than about 1500 ° C., the oxide may be undesirably formed due to oxidation of a part of the phosphor precursor depending on the crystal stability of the phosphor precursor, such as an oxide silicate phosphor.

According to one embodiment of the present invention, the method for producing a phosphor of the first aspect of the present invention may further include a step of performing a third heat treatment in the reducing atmosphere after the second heat treatment to reduce the rare earth metal, no.

For example, the third heat treatment may be performed in a reducing atmosphere to grow a crystal of the phosphor precursor formed through the second heat treatment, while reducing the active agent such as a rare earth metal, but the present invention is not limited thereto. For example, when the third heat treatment is performed at a temperature of less than about 700 ° C, a sufficient reducing atmosphere is difficult to form, resulting in a decrease in luminance and emission intensity of the phosphor, but the present invention is not limited thereto. On the other hand, when the third heat treatment is performed at a temperature higher than about 1400 DEG C, the phosphor powder may become a sintered body and lose the characteristics of the powder, but the present invention is not limited thereto.

According to an embodiment of the present invention, the reducing atmosphere may include, but is not limited to, a mixed gas of N ₂ and H ₂ , a mixed gas of inert gas and H ₂ , or a CO gas. For example, the inert gas may include, but is not limited to, He, Ne, or Ar. For example, the reducing atmosphere can be selected from the group consisting of N ₂ / H ₂ = (about 90 to about 95) / (about 10 to about 5) or Ar / H ₂ = (about 90 to about 95) / (about 10 to about 5) But it is not limited thereto.

For example, by adding the step of pulverizing the phosphor during the manufacturing process of the phosphor according to the first aspect of the present invention, it is possible to further reduce the time required for oxidation and reduction by increasing the surface area of the phosphor powder, , But is not limited thereto. For example, the pulverizing step may include a ball mill, a roll mill, a vibrating ball mill, an atomizing mill, a ball mill, a sand mill, a cutter mill a pulverizer such as a dry type pulverizer such as a cutter mill, a hammer mill or a jet mill, an ultrasonic disperser, or a homogenizer may be used, but the present invention is not limited thereto.

Second aspect of the present application, the phosphor produced by the method according to the first aspect of the invention, the phosphor is: having the composition of [M ¹ -M ² ₂ M ³ ₂ M ⁴ O ₈ + xA], wherein M ¹ Wherein M ² is an element of Group ³ , M ³ is a Group 4 element, M ⁴ is a rare earth metal ion, A is an oxide of M ³ , and x is the mole number of A , And a phosphor.

The phosphor of the second aspect of the present invention is produced according to the manufacturing method of the first aspect of the present invention, and the embodiments, examples, and all other examples and explanations of the first aspect of the present invention are not duplicated and omitted. May be applied as it is in the second aspect of the present application.

According to an embodiment of the present invention, the M ¹ may include Ca, Sr, Ba, Mg, or Be, but is not limited thereto. The composition of the phosphor to be produced may be varied by diversifying the kind of the alkaline earth metal M ¹ contained in the phosphor, but the present invention is not limited thereto. In addition, although the fluorescent characteristics of the phosphor may be affected depending on which element the phosphor contains as the alkaline earth metal, the present invention is not limited thereto.

According to one embodiment of the present invention, the M ² may include, but is not limited to, Al, Ga, or In. The composition of the phosphor to be produced can be varied by diversifying the kind of Group 3 metal M ² contained in the phosphor, but is not limited thereto. In addition, although the fluorescent property of the phosphor may be affected depending on which element is contained as the Group 3 metal, the present invention is not limited thereto.

According to an embodiment of the present invention, the M ³ may include Si, Ge, or Sn, but is not limited thereto. The composition of the phosphor to be produced may be varied by diversifying the kind of the Group 4 element M ³ contained in the phosphor, but is not limited thereto. In addition, the fluorescent characteristics of the phosphor may be affected depending on which element is contained as the Group 4 element, but the present invention is not limited thereto.

According to one embodiment of the present invention, the M ⁴ may include, but is not limited to, a divalent or trivalent cation of a rare earth metal. As described in detail in the first aspect of the present invention, when the rare earth metal ion contained in the phosphor is capable of emitting light in a wider range of colors than when the rare earth metal ion is a divalent cation, the application range of the phosphor can be extended. But is not limited to.

According to one embodiment of the present application, the M ⁴ comprises a ^{2 +} Eu, La ^{+ 2,} Ce ^{+ 2,} Nd ^{+ 2,} Gd ^{+ 2,} Tb ^{+ 2,} Dy ^2+, Er ^{+ 2,} or Yb ^{2 +} , But is not limited thereto. As described above, when the rare earth metal ion contained in the phosphor is divalent cation, it is possible to emit light in a wide range of colors, thereby expanding the application range of the phosphor, but the present invention is not limited thereto.

According to one embodiment of the present invention, the A may include, but is not limited to, SiO ₂ , GeO ₂ , or SnO ₂ . For example, when M ³ is Si, A may be SiO ₂ , but is not limited thereto. For example, when M ³ is Ge, A may be GeO ₂ , but is not limited thereto. For example, when M ³ is Sn, A may be SnO ₂ , but is not limited thereto. In the present invention, in order to improve the physical properties including the improvement of the luminance of the phosphor, the A may be included in an excessive amount, but the present invention is not limited thereto.

According to one embodiment of the present disclosure, x may be greater than about 0 and less than about 18, but is not limited thereto. Here, x represents the number of moles of the oxide of the Group 4 element and may be somewhat different from the "oxide precursor of the excess Group 4 element" used in the manufacturing method of the first aspect of the present application. Specifically, the term "oxide precursor of an excess Group 4 element" in the first aspect of the present invention includes both about 2 mol and the additionally added portion required in the basic composition of the phosphor. In the second aspect of the present invention, x means the number of moles of the oxide of the Group 4 element that is additionally added except for the portion required in the basic composition of the phosphor and is finally attached to the surface of the luminescent particles of the phosphor as crystalline or amorphous particles or isolated . For example, x may be greater than about 0 and less than about 3, greater than about 0 to less than about 6, greater than about 0 to less than about 10, greater than about 0 to less than about 14, greater than about 0 to less than about 18, Less than about 6, greater than about 3 to less than about 10, greater than about 3 to less than about 14, greater than about 3 to less than about 18, greater than about 6 to less than about 10, greater than about 6 to less than about 14, , Greater than about 10 to less than about 14, greater than about 10 to less than about 18, or greater than about 14 to less than about 18, but is not limited thereto.

For example, the phosphor may have a mixed phase of cristobalite and anorthite, but the present invention is not limited thereto. The fact that the phosphor has a mixed phase of cristobalite and anotite can be confirmed from the XRD pattern of Fig. 4 and the like of the present application. Here, the rare earth metal ion of the phosphor may be occupied within the anorthite crystal structure, but is not limited thereto.

For example, the phosphor may be one in which the intensity of the cristobalite phase increases as x increases, but the present invention is not limited thereto. For example, as the amount of the oxide precursor of the Group 4 element added during the production of the phosphor is increased, the strength of the cristobalite phase is increased, while the strength of the anotite phase is decreased, but the present invention is not limited thereto.

In this connection, FIG. 3 is a schematic diagram showing a crystal structure of [CaAl ₂ Si ₂ O ₈ : Eu ²⁺ ] as an example among the phosphors according to the second aspect of the present application. 3, the crystal structure of the phosphor [CaAl ₂ Si ₂ O ₈ : Eu ^{2 +} ] is composed of a tetrahedral silicate and a rigid framework of aluminate, wherein the Ca ^{2 +} ion May occupy interstitial sites of the framework. Due to the solid structure, the phosphor may maintain high luminescence characteristics, but the present invention is not limited thereto.

According to one embodiment of the present invention, the A may include, but is not limited to, crystals or amorphous particles that are attached to the surface of the phosphor or exist in isolation. For example, if the A is SiO _2, the SiO ₂ may be formed on the surface of the phosphor crystals, and a smaller amorphous SiO ₂ particles may be present from said fluorescent material with spaced small, crystals of the SiO ₂ And the amorphous SiO ₂ particles may coexist at the same time, but are not limited thereto. The presence of A in the phosphor can be confirmed by analyzing an optical microscope image or an FE-SEM image, but the present invention is not limited thereto.

For example, the phosphor may have a high-brightness phosphor property, a rounded particle shape, and a particle size of about 50 nm to about 20 占 퐉, but the present invention is not limited thereto. For example, the phosphor may have a wavelength of from about 50 nm to about 100 nm, from about 50 nm to about 500 nm, from about 50 nm to about 1 μm, from about 50 nm to about 10 μm, from about 50 nm to about 20 μm, from about 100 from about 100 nm to about 10 탆, from about 100 nm to about 20 탆, or from about 1 탆 to about 10 탆, from about 1 탆 to about 20 탆, But is not limited thereto.

The present invention may include, but is not limited to, a display including, for example, the phosphor. For example, the display may include, but is not limited to, a cathode ray tube, a light emitting diode (LED), a plasma display panel (PDP), or a field emission display (FED).

The present invention may, for example, include a lamp including the phosphor, but is not limited thereto.

Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited thereto.

[ Example ]

1. Manufacture of phosphor

In this embodiment, the phosphor _{[CaAl 2 Si 2 O 8:} Eu 2 + + xSiO 2] ( where, x is 0, 1, 2, 3, 4, 5, 6, or 13 mol, as a comparative example SiO ₂ + Eu < ^{2 +} & ^{gt ; is} also used) was prepared using the liquid phase method according to the first aspect of the present invention.

First, 30 wt% of Ca (NO ₃ ) ₂ .4H ₂ O (Junsei chemical Co., Japan), 50 wt% of Al (NO ₃ ) ₃ .9H ₂ O (Samchun Chemical Co., 98% was the composition of the mixed solution is mixed with the% of SiO ₂ (sol, 20 nm, Snotex-O, Nissan Chemical), and 50% by weight of _{EuCl 3 · 3H 2 O (Aldrich} grade) by weight of the solution, this cellulose powder ( avicel, Asahe). The impregnated cellulose precursor was calcined rapidly in air in a box furnace for 3 hours in air to allow the cellulose to evaporate as CO ₂ and H ₂ O gases. Thereafter, it was fired in air at 1200 DEG C for 2 hours. Then, the final phosphor [CaAl ₂ Si ₂ O ₈ to Eu ^{3 +} contained in the phosphor is fired at 1000 ℃ added for 10 hours in a N ₂ / H ₂ (95/5) in a reducing atmosphere in order to return to Eu ^{2 +} : Eu ^{2 +} + xSiO ₂ ].

In the present embodiment, each of the phosphors [SrAl ₂ Si ₂ O ₈ : Eu ^{2 +} + xSiO ₂ ] and [BaAl ₂ Si ₂ O ₈ : Eu ^{2 +} + xSiO ₂ ] are the same as above except for the types of alkaline earth metal salts Process. Here, the alkaline earth metal salt used for the production of [SrAl ₂ Si ₂ O ₈ : Eu ^{2 +} + xSiO ₂ ] was 30% by weight of Sr (NO ₃ ) ₂ .4H ₂ O (Junsei chemical Co., Japan) , And the alkaline earth metal salt used for the preparation of [BaAl ₂ Si ₂ O ₈ : Eu ^{2 +} + xSiO ₂ ] was 30 wt% BaCl ₂ (Junsei chemical Co., Japan).

2. Characterization method of phosphor

The crystal phase of each of the phosphors prepared according to Example 1 was analyzed by XRD (CuK ?,? = 1.5406, 40 kV, 20 mA, Rigaku, Japan). In addition, the photoluminescence characteristics of the phosphor were measured using a PL spectrometer (SINCO, FS-2, Korea) equipped with a 500 W xenon discharge lamp. The quenching characteristics of the phosphor were analyzed using another PL spectrometer (Drasa PRO 5300, 500 W, Korea) operating with a 5 nm slit. The emission characteristics of the phosphor particles were confirmed by an optical microscope (OLYMPUS, CKX31, MPlanN 50 X 0.75 ∞ / 0 / FN22, Japan) and a UV lamp (Filtered lamp for fluorescence, VILBER Lourmat, France). The shape of the phosphor particles was confirmed by FE-SEM (JEOL, JSM7500F, Japan).

3. Characteristic Analysis of Phosphor

[Analysis 1] X-ray diffraction  analysis ( XRD )

Since the brightness of the phosphor is improved when the crystallinity of the phosphor is excellent or when a unique crystal phase exists in the phosphor, the crystal form of the phosphor is confirmed through X-ray diffraction analysis (XRD) The luminance between the various phosphors can be comparatively analyzed.

In this regard, FIG. 4 shows XRD patterns of phosphors prepared by adding various concentrations of SiO ₂ according to the present embodiment. Specifically, FIG. 4A is a graph showing the XRD patterns of phosphors [CaAl ₂ Si ₂ O ₈ : Eu ^{₂ + +} xSiO ^2], Figure 4b phosphor _{[SrAl 2 Si 2 O 8:} Eu 2 + + xSiO 2], Figure 4c phosphor _{[BaAl 2 Si 2 O 8:} Eu 2 + + xSiO 2] is the XRD pattern .

Referring first to Figure 4a, the phosphor _{[CaAl 2 Si 2 O 8:} Eu 2 + + xSiO 2] is mainly _{CaAl 2 Si 2 O 8 (JCPDF} card # 041-1486 cyano tight) and a SiO ₂ (JCPDF card # 082-0512 cristobalite). The XRD pattern of Figure 4a is SiO ₂ The concentration of CaAl ₂ Si ₂ O ₈ Reduction phase and SiO ₂ The awards showed a clear increase. This change is due to higher SiO ₂ Concentration, that is, showed a more dominant in the case of x = 6 and 13, which was added SiO ₂ If the flux is crystalline SiO ₂ The results are shown in Fig. In general, the SiO ₂ Increase in the concentration of the CaAl ₂ Si ₂ O _8: Eu ²⁺ and wherein the reducing SiO ₂ . However, the phosphor synthesized using only SiO ₂ and Eu ^{2 +} , that is, SiO ₂ + Eu ^{2 +} , did not show any peak in the XRD pattern showing the amorphous nature of the sample. The XRD pattern of FIG. 4A suggests that excess SiO ₂ in the phosphor may exist in both crystalline and amorphous forms.

FIG. 4B corresponding to the XRD pattern of the phosphor [SrAl ₂ Si ₂ O ₈ : Eu ^{2 +} + xSiO ₂ ] also showed a SiO ₂ crystal phase similar to FIG. 4A.

On the other hand, in FIG. 4C corresponding to the XRD pattern of the phosphor [BaAl ₂ Si ₂ O ₈ : Eu ^{2 +} + xSiO ₂ ], unlike FIG. 4A and FIG. 4B, the SiO ₂ crystal phase did not appear because the excess SiO ₂ was in an amorphous form It was presumed that it existed.

4A to 4C, the size of the M ¹ Al ₂ Si ₂ O ₈ crystal pattern is decreased as the x value increases. This is because the amount of the phosphor is relatively decreased as the concentration of SiO ₂ increases Respectively.

[Analysis 2] Photoluminescence  characteristic( Photoluminescence properties , PL )

In the case of the phosphor was performed produced by the firing process in a reducing atmosphere according to the first embodiment and are therefore not an Eu ^{3 +} is reduced to 100% Eu ^{2 +,} relatively the greater the amount of the reduced rare earth metal ions, the The luminescence brightness of the phosphor increases. The emission luminance (efficiency) of the phosphor can be compared and measured by measuring the PL spectrum and confirming the absorption wavelength, emission wavelength, and intensity of the phosphor.

In this regard, the present Figure 5, as an explanation of the various added to a concentration of SiO ₂ phosphor each light emission produced by (Photoluminescence, PL) spectra in accordance with the present embodiment, in particular, Figure 5a is a phosphor [CaAl _{2 ^{Si 2 O 8: Eu 2 +}} + xSiO 2] of the excitation spectrum (dotted line), a light emitting spectrum (solid line), and 430 nm an emission intensity (sapdo) standardized by the wavelength of, and Figure 5b is a phosphor [SrAl ₂ Si ₂ O ^{_{8: Eu 2 + + xSiO 2}} ] of the excitation spectrum (dotted line) and emission spectrum (solid line), and Figure 5c is a phosphor _{[BaAl 2 Si 2 O 8:} Eu 2 + + xSiO 2] of the excitation spectrum (dotted line) and emission Spectrum (solid line).

First, referring to FIG. 5A, it can be seen that the phosphor [CaAl ₂ Si ₂ O ₈ : Eu ^{2 +} + xSiO ₂ ] exhibits wide excitation and emission spectrum. Specifically, the excitation spectrum was observed at a wavelength of 280 nm to 400 nm centered at 365 nm, and the emission spectrum was observed at a wavelength of 400 nm to 600 nm centered at 430 nm. In particular, the excitation spectrum showed two overlapping peaks centered at 320 nm (t _2g ) and 370 nm (e _g ), because the 5d orbital was isolated due to crystal field splitting peaks This is the result.

On the other hand, the emission spectrum of FIG. 5A showed two closely overlapping peaks at 430 nm and 470 nm. Eu ^{2 +} is SiO ₂ Because even though can be considered a replacement for Si ^{4 +} sites in the crystal and, Eu ^{2 +,} while the Si ^{4 +} is from 6 to 10 coordinated to different number of the charge and coordination as 4 coordination, Eu ^{2 +} is the Si ^{4 +} The site could not be occupied. In addition, the ion size of Eu ²⁺ was too large to be in the range of 1.17 to 1.35 Å, so it could not replace the Si ^{4 +} site or occupy the interstitial site of only 0.26 Å in the SiO ₂ crystal. Thus, the overlapping peak of the emission spectrum may be found to be due CaAl ₂ Si ₂ O _{8 2} of Eu ^{2 +} site is Eu ^{2 +} to create a different environment for the ions each in the crystal, which is more by the schematic diagram of Figure 3 It can be confirmed clearly.

On the other hand, the illustration in FIG. 5A shows the light emission intensity of the phosphor, or SiO ₂ Lt; RTI ID = 0.0 > SiO2 < / RTI _> As the concentration x increased from 0 mol to 5 mol, it increased proportionally. Particularly, when the x value is 5, the phosphor exhibits 110% improvement in luminescence intensity as compared with the phosphor when the x value is 0. This increase in brightness is due to the structural characteristics of the tetrahedral silicate crystals of SiO ₂ added in excess. The SiO ₂ exists in the form of SiO ₄ ^{4 -} in the crystal or amorphous state and has a rich electron at the edge thereof. The excess SiO ₂ is present on the surface of the phosphor and is reduced at a high temperature It is possible to provide a stronger reducing atmosphere because it serves to supply electrons into the phosphor. As a result, the amount of the phosphor reduced to Eu ^{2 +} increases, and as a result, the luminescent property of the phosphor is enhanced. Increased content of Eu ^{2 +} is, it can be confirmed by using a point to cause the blue light-emitting Eu ^{2 +} high. However, in the case of the phosphor having an excessively large x value, that is, the phosphor having x of 6 or 13 mol, a decrease in the emission intensity was observed rather than a saturation concentration of SiO ₂ for improving the emission intensity of the phosphor. I could confirm. The decrease in the light emission intensity was presumed to be due to the relative decrease in the content of CaAl ₂ Si ₂ O _{8 as} a light emitting material in the phosphor. Or that the role of SiO ₂ as an impurity is stronger.

On the other hand, among the phosphors of FIG. 5A, excitation and emission spectra are not shown for a sample synthesized using only SiO ₂ and Eu ^{2 +} , that is, SiO ₂ + Eu ²⁺ , from which Eu ²⁺ is ^converted to amorphous SiO ₂ I could confirm that it could not be occupied within the site.

On the other hand, the concentration of SiO ₂ , which can maximize the emission intensity of the phosphor, was somewhat different depending on the type of the alkaline earth metal contained in the phosphor, which is presumed to be due to the difference in ion size depending on the type of the alkaline earth metal. Specifically, the phosphor containing Sr showed the maximum emission intensity when the x value was 2 mol, and the maximum emission intensity when the x value was 3 mol for the phosphor containing Ba, 5c.

[Analysis 3] Optical microscope image

In this example, an optical microscope image was used to check how SiO ₂ exists in the phosphor prepared according to Example 1 above. First, the positions of all the particles were confirmed by using a light source of optical type, and when the light source was removed, ultraviolet rays of 365 nm were irradiated with a UV lamp to track which particles correspond to the fluorescent material .

In this connection, FIG. 6 shows an optical microscope image of the phosphor [CaAl ₂ Si ₂ O ₈ : Eu ^{2 +} + xSiO ₂ ] prepared by adding various concentrations of SiO ₂ according to the present embodiment, 6a to 6c are images in the absence of UV lamp illumination, and Figs. 6d to 6f are images in the presence of UV lamp illumination. 6A and 6B are images before and after UV-lamp irradiation, and FIGS. 6B and 6E are images before and after UV-lamp irradiation when x value is 3, FIG. 6F shows optical microscope images before and after UV-lamp irradiation when x value is 13.

6A to 6C in the absence of UV-lamp irradiation, it can be seen that a large number of small particles are present along with large particles in the optical microscope image. However, referring to FIGS. 6d to 6f in the case of UV-lamp irradiation, it can be seen that most of the small particles disappear and only large particles remain in the optical microscope image. Further, the sizes of the large particles of Figs. 6D to 6F were smaller than those of Figs. 6A to 6C. 6A to 6C, the particles disappeared in FIGS. 6D to 6F correspond to the SiO ₂ portion which can not emit light when irradiated with UV lamps. From this, it can be assumed that most of the small particles and the particles present on the phosphor surface are both monocrystalline or amorphous SiO ₂ , and it is possible to confirm how excessive SiO ₂ added to the phosphor of the present invention exists.

[Analysis 4] Thermal quenching ( Thermal quenching )

Of the present application 7 is prepared by the addition of SiO ₂ in various concentrations according to an embodiment of the present phosphors _{[CaAl 2 Si 2 O 8:} Eu 2 + + xSiO 2] (x is 0, 3, and 13) Thermal stability.

If the SiO ₂ contained in the phosphor is to be coated on the surface of the Eu ^{2 +} -doped CaAl ₂ Si ₂ O ₈ phosphor, the SiO ₂ should be an amorphous phase rather than a crystalline phase, and the amorphous phase SiO ₂ has a thermal stability It is necessary to show that the thermal stability of the phosphor is improved.

However, even when 7, the thermal stability of the phosphor was shown to substantially the same value regardless of the addition of Status of SiO _2, not from this that the SiO ₂ on the amorphous coating to the phosphor, that the SiO ₂ It was presumed that it was adhered on the surface of the phosphor in a crystalline form.

[Analysis 5] FE - SEM  image

In general, the more uniform the shape of the phosphor particles and the closer to the spherical shape, the more favorable the application to the apparatus, and the shape of the phosphor particles can be confirmed by the FE-SEM image.

In this regard, FIG. 8 shows an FE-SEM image of each of the phosphors prepared by adding SiO ₂ at various concentrations according to the present embodiment. Specifically, FIGS. 8A to 8D show the phosphors [CaAl ₂ Si ^{_{2 O 8: Eu 2 + +}} xSiO 2], Fig. 8e through 8h are phosphor _{[SrAl 2 Si 2 O 8:} Eu 2+ + xSiO 2], Figure 8i to 8l is also phosphor [BaAl ₂ Si ₂ O _8: Eu ^{2 +} + xSiO ₂ ].

8A to 8L, the particle size and shape of the phosphor of the present invention were not uniform, and a large number of small particles existed on the surface of the phosphor, so that it was difficult to apply to the device itself. However, this is because the SiO ₂ crystal is adhered to the surface of the phosphor of the present invention, so that a strong reducing atmosphere is provided by providing excess electrons in the phosphor to obtain a phosphor having improved brightness, Can be resolved by smoothing the crystal shape through additional cleaning.

It will be understood by those of ordinary skill in the art that the foregoing description of the embodiments is for illustrative purposes and that those skilled in the art can easily modify the invention without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be interpreted as being included in the scope of the present invention .

Claims (20)

Obtaining a mixed solution comprising an alkaline earth metal salt, a rare earth metal salt, a Group 3 metal salt, and an oxide precursor of an excessive Group 4 element; And
Adding cellulose to the mixed solution and then performing heat treatment
/ RTI >
As a method for producing a phosphor,
Wherein the oxide precursor of the excess Group 4 element is an oxide precursor of a Group 4 element in an amount exceeding 2 mol required in the phosphor composition itself and contains more than 2 mol and less than 20 mol.
Gt;
The method according to claim 1,
Wherein the alkaline earth metal salt comprises a salt of Ca, Sr, Ba, Mg, or Be.
The method according to claim 1,
Wherein the rare earth metal salt comprises a salt of Eu, La, Ce, Nd, Gd, Tb, Dy, Er, or Yb.
The method according to claim 1,
Wherein the Group III metal salt comprises a salt of Al, Ga, or In.
The method according to claim 1,
Oxide precursor of the Group 4 element is _{SiO 2, Si (OH) 4} , SiH 4, Si (OC 2 H 5) 4, water soluble _{silane, GeO 2, Ge (OH)} 4, GeH 4, Ge (OC 2 H 5 ) ₄ , SnO ₂ , Sn (OH) ₄ , SnH ₄ , or Sn (OC ₂ H ₅ ) ₄ .
delete The method according to claim 1,
Wherein the mixed solution is obtained by uniformly mixing the alkaline earth metal salt, the rare earth metal salt, the Group 3 metal salt, and the oxide precursor of the excess Group 4 element.
The method according to claim 1,
Wherein the cellulose includes one selected from the group consisting of cellulose powder, cellulose sheet, spherical cellulose, water-soluble cellulose, pulp, crystallized cellulose, amorphous cellulose, and combinations thereof.
The method according to claim 1,
Wherein the heat treatment includes a first heat treatment performed at 150 ° C to 600 ° C and a second heat treatment performed at 600 ° C to 1500 ° C sequentially.
10. The method of claim 9,
Further comprising a third heat treatment in a reducing atmosphere after the second heat treatment to reduce the rare earth metal.
11. The method of claim 10,
Wherein the reducing atmosphere includes a mixed gas of N ₂ and H ₂ , a mixed gas of an inert gas and H ₂ , or a CO gas.
A phosphor produced by the method according to claim 1,
The phosphor has a composition of [M ¹ -M ² ₂ M ³ ₂ O ₈ : M ⁴ + xA]
Wherein M ¹ is an alkaline earth metal,
M ² is a Group 3 metal,
M ³ is a Group 4 element,
M ⁴ is a rare earth metal ion,
Wherein A is an oxide of M ^{3, which} is present as crystals or amorphous particles attached to the surface of the phosphor or isolated,
Wherein x is the number of moles of A and is greater than 0 and less than 18,
Phosphor.
13. The method of claim 12,
Wherein M ¹ comprises Ca, Sr, Ba, Mg, or Be.
13. The method of claim 12,
And M ² is Al, Ga, or In.
13. The method of claim 12,
Wherein M ³ comprises Si, Ge, or Sn.
13. The method of claim 12,
And M < ⁴ > includes a divalent or trivalent cation of a rare earth metal.
13. The method of claim 12,
The M ⁴ is ^{2 +} Eu, La ^{+ 2,} Ce ^{+ 2,} Nd ^{+ 2,} Gd ^{+ 2,} Tb ^{+ 2,} Dy ^{+ 2,} Er ^{+ 2,} or the fluorescent material comprises a Yb ^{+ 2.}
13. The method of claim 12,
And A is the one containing SiO _2, GeO _2, or SnO _2, the phosphor.
delete delete

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