JP5135812B2 - Phosphor based on nitride or oxynitride, method for producing the same, phosphor-containing composition using the same, light emitting device, lighting device, and image display device - Google Patents

Description

  The present invention relates to a method for producing a phosphor having nitride or oxynitride as a base, a phosphor produced by the method, a composition containing the phosphor, and a light-emitting device configured using the phosphor Furthermore, the present invention relates to an image display device configured using the light emitting device, and an illumination device. Specifically, a phosphor manufacturing method that is simpler and less expensive, a phosphor manufactured by the method, a composition including the phosphor, and a light-emitting device configured using the phosphor, The present invention relates to an image display device configured using the light-emitting device and an illumination device.

  As a prior art relating to a light emitting device having an excitation light source and a phosphor that converts the wavelength of at least part of light from the excitation light source, a blue light emitting diode element and a phosphor that absorbs blue light and emits yellow light White light-emitting diodes that are configured are known and have been put to practical use in various lighting applications.

  Further, in recent years, phosphors used for lighting applications and the like include alkaline earth metal elements as shown in Patent Document 1, Patent Document 2, Patent Document 3, and Patent Document 4, for example, nitrides and A phosphor based on oxynitride has been proposed. Phosphors based on nitride or oxynitride are conventional silicate phosphors, phosphate phosphors, aluminate phosphors, borate phosphors, sulfide phosphors, oxysulfide phosphors Many of them have long-wavelength light emission compared to phosphors such as the above, and are excellent in durability.

However, when producing a phosphor containing an alkaline earth metal element-containing nitride or oxynitride as a base, generally, an alkaline earth metal nitride or alkaline earth metal amide compound having low stability is used. An alkaline earth metal imide compound or an alkaline earth metal simple substance is used. Therefore, there are the following problems.
In other words, alkaline earth metal nitrides and alkaline earth metal elements are decomposed and oxidized in the atmosphere, so it is necessary to handle them in an atmosphere such as nitrogen or argon. A large amount of equipment, which contributes to an increase in manufacturing costs. Also, generally available alkaline earth metal nitrides contain some oxygen, and when phosphors are produced using them, the oxygen content in the phosphors cannot be reduced and the light emission characteristics are degraded. There is also the problem that there is a possibility of doing.

Therefore, as a production method that may solve the above-mentioned problem, a metal oxide or a compound capable of generating a metal oxide is used as a phosphor raw material, and they are reduced by heating them in the presence of carbon powder. At the same time, a production method for synthesizing nitride by reacting with nitrogen gas (that is, a carbothermal method, hereinafter may be abbreviated as “CRN method”) has been proposed (Patent Document 5, Patent). Reference 6).
WO2005-52087A1 WO2001-040403 JP 2002-363554 A Special table 2005-530917 : WO2005-049763A1 JP-A-2005-336450

In the CRN method, since carbon powder is used as a reducing agent, the reduction and nitridation of the phosphor material become insufficient, such as when the contact between the phosphor material and the carbon powder becomes insufficient. Furthermore, carbon used as a reducing agent may remain in the phosphor or as a mixture with the phosphor. For this reason, it has been difficult to produce a phosphor having excellent emission characteristics using the CRN method.
Therefore, do not use carbon powder, which is essential in the CRN method, and use raw materials that are chemically unstable and difficult to handle in the atmosphere, such as alkaline earth metal nitrides and alkaline earth metal alone. In addition, there has been a demand for a production method capable of producing a phosphor having a high light emission characteristic and based on nitride or oxynitride.

  The present invention has been made in view of the above-mentioned problems, and its object is to provide an excellent method for producing a phosphor based on nitride or oxynitride, and to produce the produced phosphor. An object of the present invention is to provide a phosphor-containing composition and a light emitting device using the phosphor, and an image display device and an illumination device using the light emitting device.

  As a result of intensive studies in view of the above problems, the present inventors have not used carbon powder, which is essential in the CRN method, and are chemically inferior like an alkaline earth metal nitride or an alkaline earth metal alone. The present inventors have found a method for producing a phosphor without using a raw material that is stable and difficult to handle in the atmosphere. That is, by using as a raw material a compound having one or more metal elements constituting the phosphor and having at least one C element to which no O element is directly bonded, reduction of the phosphor raw material, and It was found that nitriding could be performed sufficiently, and when a phosphor was produced by this method, a phosphor having a low carbon content and excellent emission intensity and stability was obtained, and the present invention was completed.

  That is, the gist of the present invention resides in the following [1] to [22].

  [1] Nitride or oxynitridation characterized by using as a raw material a compound having one or more metal elements constituting the phosphor and having one or more C elements to which no O element is directly bonded A method for producing a phosphor based on an object.

[2] The compound is selected from the group consisting of Group 2 elements, Group 3 elements, Group 12 elements, Group 13 elements, and Group 14 elements of the periodic table as metal elements constituting the phosphor. The method for producing a phosphor having a nitride or oxynitride as a base material according to [1], comprising at least one element.

[3] The nitride or oxynitride according to [1] or [2], wherein the compound has at least one group 2 element of the periodic table as a metal element constituting the phosphor. The manufacturing method of the fluorescent substance which uses as a base.

[4] The method for producing a phosphor based on a nitride or oxynitride according to any one of [1] to [3], wherein the compound does not contain an O element.

[5] The method for producing a phosphor based on a nitride or oxynitride according to any one of [1] to [4], wherein the compound further contains an N element.

[6] The method for producing a phosphor based on the nitride or oxynitride according to any one of [1] to [5], wherein the compound further has a substituted or unsubstituted hydrocarbon group .

[7] The method for producing a phosphor using the nitride or oxynitride according to any one of [1] to [6], wherein the compound further has a carbonyl group.

[8] Any of [1] to [4], wherein the compound is at least one selected from the group consisting of a metal salt of cyanamide (H ₂ N—CN), a metal carbide, and a metal cyanide. A method for producing a phosphor using the nitride or oxynitride as described above as a base material.

[9] The phosphor according to [8], wherein the compound is a metal salt of cyanamide (H ₂ N—CN) containing a Group 2 element of the periodic table. Manufacturing method.

[10] The method for producing a phosphor based on a nitride or oxynitride according to any one of [1] to [3], wherein the compound has a substituted or unsubstituted hydrocarbon group.

[11] The method for producing a phosphor based on the nitride or oxynitride according to any one of [1] to [3] and [10], wherein the compound further has a carbonyl group.

[12] The nitride according to [11], wherein the compound has a carboxyl group as the carbonyl group and has at least one of Group 2 elements and / or Group 3 elements in the periodic table. A method for producing a phosphor using oxynitride as a base material.

[13] A phosphor based on a nitride or oxynitride produced by the method according to any one of [1] to [12].

[14] The phosphor containing the nitride or oxynitride as a matrix according to [13], wherein the carbon content is 0.5% by weight or less.

[15] The phosphor based on the nitride according to [14], wherein the oxygen content is 0.5% by weight or less.

[16] The phosphor containing the nitride or oxynitride according to any one of [13] to [15], containing Si element.

[17] The phosphor based on the nitride or oxynitride according to any one of [13] to [16], which contains at least one group 2 element of the periodic table.

[18] A phosphor-containing composition comprising the phosphor according to any one of [13] to [17] and a liquid medium.

[19] A first light emitter and a second light emitter that emits visible light when irradiated with light from the first light emitter, and the second light emitter includes [13] to [17]. A light emitting device comprising at least one of the phosphors according to any one of the above as a first phosphor.

[20] In the above [19], the second phosphor includes at least one phosphor having a light emission peak wavelength different from that of the first phosphor as the second phosphor. The light-emitting device of description.

[21] An image display device comprising the light-emitting device according to [19] or [20] as a light source.

[22] An illumination device comprising the light-emitting device according to [19] or [20] as a light source.

According to the production method of the present invention, a phosphor having a nitride or oxynitride excellent in emission characteristics such as emission intensity as a base can be produced. The production method of the present invention is also highly industrial because the phosphor material is stable and relatively inexpensive, and the production process is simple.
Further, by using the phosphor manufactured by the manufacturing method of the present invention, a light emitting device having excellent emission intensity can be obtained.
This light-emitting device is suitably used for an image display device or a lighting device.

  Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments, and various modifications can be made within the scope of the gist of the present invention.

[1. Method for producing phosphor]
The phosphor production method of the present invention includes at least a step of mixing respective raw materials (mixing step) and a step of baking the obtained raw material mixture (firing step), and [1-1. It is characterized by using at least one compound described in [Raw compound].

[1-1. Raw material compound]
In the method for producing a phosphor of the present invention, one or more metal elements constituting the phosphor are used as a raw material compound, and one C (carbon) element to which no O (oxygen) element is directly bonded is used. At least one compound having the above (hereinafter sometimes referred to as “C-containing raw material compound”) is used.

  The C-containing raw material compound is a group 2 element, group 3 element, group 12 element of the periodic table as a metal element (hereinafter sometimes referred to as “phosphor constituent element”) constituting the phosphor for production. It may have at least one element selected from the group consisting of Group 13 elements and Group 14 elements. Among these, the C-containing raw material compound preferably has at least one Group 2 element in the periodic table as a phosphor constituting element for production purposes.

  Specific examples of the Group 2 element include Mg, Ca, Sr, Ba, and the like. Specific examples of the Group 3 element include Sc, Y, and lanthanoid elements (La, Ce, Pr, Nd, Pm, Sm). , Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu), etc., as specific examples of Group 12 elements, Zn, Cd, etc., and as specific examples of Group 13 elements, Al , Ga, In and the like. Among these, at least one selected from the group consisting of Mg, Ca, Sr, Ba, La, and Y is preferable, and at least one selected from the group consisting of Ca, Sr, and Ba is preferable. More preferred.

The C-containing raw material compound is usually a solid powder. The weight median diameter (D ₅₀ ) is usually 100 μm or less, preferably 50 μm or less, 30 μm or less, and usually 0.1 μm or more, preferably 1 μm or more. If the weight median diameter (D ₅₀ ) is too large, it tends to be difficult to sufficiently mix with other raw material compounds, and may remain unreacted even when heated. On the other hand, if the weight median diameter (D ₅₀ ) is too small, the raw material compounds tend to aggregate, and the ratio of surface portions that are susceptible to oxidation and hydration tends to increase. May be indicated.

  The C-containing raw material compound only needs to have one or more C elements to which the O element is not directly coordinated, and may or may not have the O element. Hereinafter, the case where the C-containing raw material compound contains an O element and the case where it does not contain an O element will be described in detail.

[1-1-1. When O element is not included]
When the C-containing raw material compound does not have an O (oxygen) element, the C-containing raw material compound may have an N (nitrogen) element. The C-containing raw material compound containing N element includes cyanide, metal ions and cyanamide (H ₂ N—CN), and various metal salts of cyanamide formed according to the valence of the metal element (hereinafter referred to as “metal salt”). , A metal ion and [N (CN) ₂ ] ^−, and various dicyanamide metal salts formed according to the valence of the metal element (hereinafter referred to as “cyanamide compound”). And may be referred to as “dicyanamide compounds”).

  More specifically, examples of the C-containing raw material compound include a cyanamide compound, a dicyanamide compound, a metal carbide, and a metal cyanide. Among these, a cyanamide compound is preferable, and a cyanamide compound containing a Group 2 element of the periodic table is particularly preferable.

Metal carbide refers to a compound of carbon and a positive element. As a specific example, a carbide represented by M ₂ C of ₂ C, etc. Be, the carbide represented by M ₄ C _3, such as _{Al 4 C 3, Li 2 C} 2, Na 2 C 2, K 2 C 2, carbides represented by _{rb 2 C 2, Cs 2 C} 2 , etc. of the _{M 2 C 2, BeC 2,} MgC 2, CaC 2, SrC 2, BaC 2, ZnC 2, CdC 2, CeC 2, PrC 2, SmC 2 , such as carbides represented by MC ₂ such YC ₂ and the like.

Metal cyanide refers to a salt of hydrogen cyanide (HCN). Specific examples include cyanides such as alkali metals, alkaline earth metals, Zn, and Cd. Specific examples of the alkali metal cyanide include NaCN, KCN, RbCN, CsCN and the like. Specific examples of the alkaline earth metal cyanide include Ca (CN) ₂ , Sr (CN) ₂ , Ba (CN) _{2 and the} like. Specific examples of the cyanide of Zn and Cd include Zn (CN) ₂ and Cd (CN) ₂ .

As described above, the cyanamide compound is a metal salt of various cyanamides containing metal ions and cyanamide (H ₂ N—CN) and formed according to the valence of the metal element. The cyanamide compound preferably contains a divalent metal element, and is more preferably a Group 2 element metal of the periodic table. Among them, a cyanamide compound containing Mg, Ca, Sr, Ba or the like is preferable, and specific examples of the cyanamide compound include CaCN ₂ and BaCN ₂ .

As described above, the dicyanamide compound is a metal salt of various dicyanamides containing a metal ion and dicyanamide ([N (CN) ₂ ] ⁻ ) and formed according to the valence of the metal element. The metal element contained in the dicyanamide compound is preferably a divalent metal element or a trivalent metal element, and more preferably a Group 2 metal element, a lanthanoid element, Sc, or Y of the periodic table. Specific examples include Ln (N (CN ₂ )) ₃ (Ln represents one or more elements selected from lanthanoid elements, Sc and Y), M ²⁺ (N (CN ₂ ) ) ₃ (M represents one or more elements selected from Mg, Ca, Sr, Ba, Zn, and Cd).

It is known that calcium cyanamide is generated from metal carbide, metal cyanide, and the like by the following reaction. Therefore, in the present invention, CaCN ₂ may be added to the raw material from the beginning, or a compound capable of generating CaCN ₂ may be used as the raw material and may be generated during the reaction.
Examples of the reaction in the case of containing a calcium element as the metal element constituting the phosphor will be described below.

When calcium carbide is heated to 950 ° C. to 1200 ° C. in a nitrogen stream, it becomes calcium cyanamide in the next reaction.
CaC ₂ + N ₂ → CaCN ₂ + C
Alternatively, calcium cyanamide can be obtained by reacting calcium carbonate or calcium oxide at 600 ° C. to 850 ° C. in an atmosphere containing ammonia and carbon monoxide.
CaCO ₃ + 2NH ₃ + 3CO → CaCN ₂ + 3H ₂ + 3CO ₂
CaO + 2CO + 2NH ₃ → CaCN ₂ + H ₂ O + 2H ₂ + CO ₂
Further, calcium cyanamide can be synthesized by heating dicyandiamide and calcium oxide.
H ₄ C ₂ N ₄ + 2CaO → 2CaCN ₂ + 2H ₂ O
Furthermore, it is known that when calcium cyanide Ca (CN) ₂ is heated, the following reaction occurs and calcium cyanamide is obtained.
Ca (CN) ₂ → CaCN ₂ + C

(Action mechanism)
The C-containing raw material compound having no O (oxygen) element as described above is nitrogen contained in the phosphor raw material, or [1-2. It reacts with nitrogen contained in the atmospheric gas in the firing step described in the manufacturing method] to produce metal nitride. The produced metal nitride reacts with other raw materials to produce a phosphor based on the desired nitride or oxynitride. In the reaction in this firing step, the carbon contained in the phosphor material is considered to have a reducing action. Specifically, as an impurity element, an oxidizing component such as oxygen or water contained in the atmospheric gas or the phosphor material. It is considered that it contributes to making it possible to produce phosphors having an effect of suppressing unexpected reactions such as oxidation of the phosphors due to, and having excellent light emission characteristics.

[1-1-2. When having O element]
When the C-containing raw material compound has O (oxygen), the C-containing raw material compound may be a metal salt of an organic functional group having a substituted or unsubstituted hydrocarbon group. The C-containing raw material compound preferably has a functional group involved in the bonding of metal elements in addition to the substituted or unsubstituted hydrocarbon group.

(Regarding functional groups involved in coordination of metal elements)
The functional group involved in the coordination of the metal element is not particularly limited, but is preferably a carbonyl group, a hydroxyl group, or the like because a stable bond is easily generated with the metal element. Examples of the carbonyl group include a carboxyl group and an amide group, and among them, a carboxyl group is more preferable because it can easily form a stable compound with a metal element.

(About hydrocarbon groups)
The hydrocarbon group is not particularly limited, but is a substituted or unsubstituted linear hydrocarbon group, a substituted or unsubstituted branched hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted hydrocarbon group. An alicyclic hydrocarbon group etc. are mentioned. Among these, a substituted or unsubstituted linear hydrocarbon group is preferable. A specific example will be described below.

  The linear hydrocarbon group contained in the C-containing raw material compound may be a saturated fatty acid group or an unsaturated fatty acid group.

When the straight-chain hydrocarbon group is a saturated fatty acid group, it is preferably a straight-chain saturated fatty acid group from a methyl group having 1 carbon atom to a lactel group having 31 carbon atoms. Among them, the linear hydrocarbon group preferably has 1 to 10 carbon atoms, and particularly preferably 1 to 5 carbon atoms. When the number of carbon atoms exceeds 10, the phosphor becomes black at the time of firing, and the light emission characteristics may deteriorate. Accordingly, the saturated fatty acid group is preferably a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, or the like. As such a C-containing raw material compound, a carboxylate of saturated fatty acid from acetic acid (CH ₃ COOH) to lacteric acid (C ₃₁ H ₆₃ COO) can be used, and more specifically, acetic acid, It is preferable to use a metal salt such as propionic acid, butyric acid, valeric acid or hexanoic acid.

When the straight chain hydrocarbon group is an unsaturated fatty acid group, specific examples include unsaturated fatty acid groups containing at least one or more double bonds including a vinyl group and an allyl group. Specific examples of the C-containing raw material compound containing these unsaturated fatty acid groups are preferably metal salts such as acrylic acid (CH ₂ CHCOOH) and crotonic acid (CH ₃ CHCHCOOH).

Specific examples of the branched hydrocarbon group contained in the C-containing raw material compound include isopropyl group, isobutyl group, and tert-butyl group. Specific examples of compounds containing these include metal salts such as isobutyric acid ((CH ₃ ) ₂ CHCOOH), isovaleric acid ((CH ₃ ) ₂ CHCH ₂ COOH), and pivalic acid ((CH ₃ ) ₃ CCOOH). preferable.

  The aromatic hydrocarbon group contained in the C-containing raw material compound includes a phenyl group and its derivative, a derivative of a compound in which two or more benzene rings such as represented by biphenyl and the like are independently separated, naphthalene, anthracene Groups derived from compounds having a condensed cyclic structure as typified by these and their derivatives, etc. Therefore, specific examples of the C-containing raw material compound containing an aromatic hydrocarbon group include benzoic acid, phthalate Examples thereof include metal salts such as acid and salicylic acid.

  As the alicyclic hydrocarbon group contained in the C-containing raw material compound, a ring is constituted by a dozen or more carbon atoms from a small ring compound such as a three-membered ring or a four-membered ring that does not belong to an aromatic group. Examples include groups derived from cyclic compounds and derivatives thereof. Furthermore, a group derived from a heterocyclic compound containing a nitrogen atom at a position other than the carbon atom adjacent to the carbon directly bonded to oxygen is also included. Accordingly, specific examples of the C-containing raw material compound containing an alicyclic hydrocarbon group include metal salts such as cyclohexanecarboxylic acid.

(Preferred example of C-containing raw material compound)
As the C-containing raw material compound, various metal carboxylates are preferably used. This is because it is easy to form a stable compound with a metal element.

Specific examples of the metal carboxylate include compounds having one carboxyl group such as acetate and propionate. Further, a metal salt of a carboxylic acid in which a plurality of carboxyl groups are contained in one molecule such as succinic acid (HOOC— (CH ₂ ) ₂ —COOH), or a carboxyl group such as citric acid (HO—C— (COO) ₃ ) A metal salt of a compound containing both a hydroxyl group and a hydroxyl group can also be suitably used as the C-containing raw material compound.

  Among the above, the compound is a compound having a carboxyl group and a Group 2 element or Group 3 element in the periodic table (that is, a carboxylate of Group 2 element or Group 3 element in the periodic table). Particularly preferred are strontium acetate, calcium acetate, strontium succinate, calcium succinate and the like.

  On the other hand, when a metal salt of a carboxylic acid having no carbon to which oxygen is not directly bonded, such as formic acid, is used, the reducing action is weak and the emission characteristics of the phosphor tend to be lowered.

(Action mechanism)
The C-containing raw material compound as described above contains one or more C elements to which the O element is not directly bonded although it contains the O element, and the portion of the C element acts as a reducing agent, and the nitrogen atmosphere When heated in the medium, the phosphor material can be reduced and nitrided. In particular, the compound (acetate salt, propionate salt) having the hydrocarbon group (methyl group, ethyl group, etc.) exhibits a strong reducing action of the C element and H (hydrogen) element contained in the hydrocarbon group. The phosphor raw material can be sufficiently reduced and nitrided, which is preferable.

  However, compounds containing only the above functional groups such as a carboxyl group and a hydroxyl group (for example, formate and oxalate) are decomposed when heated to become carbon monoxide or carbon dioxide, so that the reducing action is weak. It is not preferable.

[1-2. Production method]
<Raw material>
In the production of the phosphor of the present invention, the above [1-1. In the case of using other raw material compounds in addition to the C-containing raw material compound described in [Raw material compound], the compound used in combination is not particularly limited as long as the target phosphor can be produced. For example, the following compounds Can be used together as a raw material.

Specific examples of the Al source include metal Al and AlN. Specific examples of the Si source include metal silicon, α-type or β-type Si ₃ N ₄ , silicon diimide (Si (NH) ₂ ), etc., among which α-type Si ₃ N ₄ which is easily available is used. Is preferred.

  Moreover, as a raw material containing an activation element, Ce, Cr, Mn, Fe, Co, Ni, Cu, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb are used. A single metal having one or more selected elements or a compound thereof can be used, and more specifically, an oxide, a nitride, a halide, or the like can be used.

Among the above examples, when it is desired to manufacture a phosphor with a low content of oxygen as an impurity, it is preferable to use a single metal or a nitride. In particular, when a compound containing an element constituting the target phosphor and a nitride that is stable in the air exists, it is preferable to use the nitride. Specifically, Si ₃ N ₄ or the like is preferably used as the Si source, and AlN is preferably used as the Al source. However, oxides that are readily available can also be used.

Hereinafter, the raw materials will be illustrated more specifically.
In the case of producing a nitride phosphor whose host crystal is represented by CaAlSiN ₃ , for example, the following compounds can be used as raw materials.
As the Ca source, CaCN ₂ can be used, and CaCO ₃ , CaO, or the like may be used as a part of the Ca source. The use ratio of CaCO ₃ , CaO, etc. is 0 mol% to 50 mol% of the Ca mole amount usually required.
AlN can be used as the Al source.
Si ₃ N ₄ can be used as the Si source.

Moreover, when manufacturing the nitride fluorescent substance whose base crystal is represented by Sr ₂ Si ₅ N ₈ , for example, the following compounds can be used as raw materials.
As the Sr source, Sr (CH ₃ COO) ₂ .0.5H ₂ O can be used, and SrCO ₃ or the like may be used as a part of the Sr source. The use ratio of SrCO ₃ or the like is 0 mol% to 50 mol% of the normally required Sr mol amount.
Si ₃ N ₄ can be used as the Si source.

The weight median diameter (D ₅₀ ) of these raw material compounds is usually 100 μm or less, preferably 50 μm or less, more preferably 30 μm or less, and usually 0.1 μm or more for the same reason as in the aforementioned C-containing raw material compound. The thickness is preferably 1 μm or more.

<Mixing process>
Although the method in particular of mixing each raw material is not restrict | limited, The method of the following (A) and (B) is mentioned as an example.

  (A) Dry pulverizer such as hammer mill, roll mill, ball mill, jet mill, etc., or pulverization using mortar and pestle, etc., and mixer such as ribbon blender, V-type blender, Henschel mixer, etc., or mortar and pestle are used. A dry mixing method that combines mixing and crushing and mixing each raw material.

  (B) Add a solvent or dispersion medium such as water to each raw material, mix using a pulverizer, mortar and pestle, or evaporating dish and stirrer, etc. to make a solution or slurry, and then spray dry and heat Wet mixing method that is dried by drying or natural drying.

<Baking process>
The phosphor of the present invention can be produced by placing the raw material mixture obtained in the mixing step in a heat-resistant container such as a crucible or a tray made of a material having low reactivity with each raw material and baking it. In the firing step, sufficient temperature and time for mutual diffusion of each ion are required to promote the solid phase reaction.

The heat-resistant container is preferably made of a material that has low reactivity between the raw material mixture and the heat-resistant container and is less contaminated with impurities. Specific examples of the material of the heat-resistant container include metals such as molybdenum and tungsten, nitrides such as BN, carbides such as SiC and B ₄ C, and borides such as ZrB ₂ . Among these, ZrB ₂ , molybdenum, and BN are preferable. ZrB ₂ is a ceramic that is electrically conductive and difficult to deform, and is particularly preferable when heated by a high-frequency heating method. Molybdenum is particularly preferable because it has low reactivity with the raw material mixture, and BN is also preferable because it is insulating and has good thermal conductivity.

  The firing temperature (maximum temperature reached) is usually 1000 ° C or higher, preferably 1200 ° C or higher, more preferably 1450 ° C or higher, and usually 2500 ° C or lower, preferably 2000 ° C or lower, more preferably 1800 ° C. is there. When the heating temperature is lower than 1200 ° C., the solid phase reaction between the raw material mixture may be insufficient, and the reduction nitridation reaction does not easily occur, so that the target phosphor may not be synthesized. Moreover, when the heating temperature is higher than 2500 ° C., an expensive heating furnace is required, and the consumption of firing energy tends to increase.

  The pressure during firing is usually atmospheric pressure or under pressure, and is preferably 10 atm or less in accordance with Japanese legal regulations. Of course, it is also possible to heat under pressure, and in that case, the pressure is usually 2000 atm or less.

  The firing time varies depending on the temperature and pressure during firing, but is usually 10 minutes or longer, preferably 1 hour or longer, and usually 24 hours or shorter, preferably 10 hours or shorter.

As an atmosphere at the time of firing, nitrogen or a single atmosphere of a nitriding gas containing nitrogen atoms such as NH ₃ , or an inert gas such as argon, hydrogen, carbon monoxide in the nitriding gas Or the mixed atmosphere which added 1 type, or 2 or more types of reducing gas is preferable. Among these, a nitrogen gas atmosphere is preferable in terms of easy handling. Further, a mixed atmosphere of hydrogen and nitrogen is preferable in terms of high reducibility, and conversely, if it is necessary to perform nitridation gently, a mixed atmosphere of argon and nitrogen may be used.

  Alternatively, after heating in a nitriding atmosphere, baking may be performed again in an inert atmosphere or a reducing atmosphere. Thereby, the activation element can be further stabilized in the host crystal of the phosphor. As a specific example of the inert atmosphere in this case, nitrogen or argon and a mixed atmosphere thereof are preferable. As a specific example of the reducing atmosphere, nitrogen or argon and a mixed atmosphere thereof include reducing hydrogen, one An atmosphere in which carbon oxide is mixed is preferable. An atmosphere of reducing gas alone can also be used.

  In addition, performing firing a plurality of times in a reducing atmosphere is also effective in improving light emission characteristics such as luminance. In addition, it is preferable to take out the contents from the crucible before reheating, crush it, and then fill the crucible again and heat it to obtain a uniform product.

  Moreover, the flux component that promotes crystal growth, which will be described later, may be mixed into the raw material from the beginning, or may be added before the second and subsequent heating.

<Flux>
In the firing step, it is preferable that a flux coexists in the reaction system from the viewpoint of growing good crystals. The type of flux is not particularly limited, but examples include NH ₄ Cl, LiCl, NaCl, KCl, RbCl, CsCl, MgCl ₂ , CaCl ₂ , BaCl ₂ , SrCl ₂ , chlorides, LiF, NaF, KF, RbF, _{CsF, MgF 2, CaF 2,} BaF 2, SrF 2, AlF 3 fluoride such, LiBr, NaBr, KBr, RbBr , CsBr, MgBr, etc. bromides such as _{CaBr 2, BaBr 2, SrBr 2} , AlBr 3 is cited It is done. Among them, it is preferable to use chloride and / or fluoride, and it is more preferable to use chloride. In addition, it is preferable to use a halide of an element constituting the matrix of the target phosphor. The amount of flux used varies depending on the type of raw material and the material of the flux, but is usually 0.01% by weight or more, further 0.1% by weight or more, and usually 20% by weight, based on the total weight of the raw materials Hereinafter, the range of 10% by weight or less is more preferable. If the amount of flux used is too small, the effect of the flux will not appear, and if the amount of flux used is too large, the flux effect will be saturated, or it will be incorporated into the host crystal and change the emission color or cause a decrease in brightness There is. These fluxes may be used alone or in combination of two or more in any combination and ratio.

<Post-processing>
After the above-described firing step, treatments such as pulverization, washing, drying, and classification are performed as necessary.
It is preferable to wash the phosphor using acid or alkali at the time of washing, because an impurity phase other than the phosphor host crystal such as flux adhering to the phosphor surface can be removed and the light emission characteristics can be improved.

  Further, it may be subjected to surface treatment. For example, by attaching fine particles such as silica, alumina, calcium phosphate or the like to the surface, powder characteristics (aggregation state, dispersibility in solution, sedimentation behavior, etc.) can be improved. For the post-treatment after the heat treatment, a generally known technique is used for known phosphors, for example, phosphors used in cathode ray tubes, plasma display panels, fluorescent lamps, fluorescent display tubes, X-ray intensifying screens, and the like. It can be used and can be appropriately selected according to the purpose, application, and the like.

  As described later, the phosphor obtained by the above-described method has a low carbon content and a high light emission characteristic.

[2. Phosphor]
[2-1. Characteristics of phosphor etc.]
According to the method for producing a phosphor of the present invention, a phosphor whose matrix is a nitride or oxynitride (hereinafter referred to as “the phosphor of the present invention”) can be produced. It is suitable for the production of a phosphor whose matrix is a nitride.
Note that a phosphor whose base material is an oxynitride can be suitably used when it is necessary to replace the O element in the raw material with the N element in the firing step.

  In the present specification, the matrix of the phosphor means a crystal or glass (amorphous or amorphous) that can dissolve the activator element, and without containing the activator crystal or glass (non-crystal). Including those that emit light themselves (crystalline, amorphous).

  The nitride is a compound of nitrogen and an element more positive than this, and may contain oxygen as an impurity as long as the crystal structure can maintain substantially the same structure as that containing no oxygen. Good. Specifically, the oxygen content is 5% by weight or less.

Further, with the oxynitride refers to nitride oxygen is present in the crystal structure as a constituent element, in particular the general formula _{Ca p (Si, Al) 12} (O, N) 16: Table with Eu _q is the Ca-α-SiAlON, the general formula _{(Si, Al) 6 (O} , N) 8: β-SiAlON and the like represented by the Eu _r and the like.

  The phosphor of the present invention has the following characteristics.

(Carbon content)
The phosphor of the present invention has a carbon content of usually 0.5% by weight or less, preferably 0.3% by weight or less, particularly preferably 0.2% by weight or less.
When the carbon content is more than the above range, the phosphor powder tends to be dark and easily colored, and the light emitted from the excitation light or the phosphor may be absorbed, resulting in a decrease in luminous efficiency. In addition, carbon incorporated into the crystal may cause lattice defects.
The carbon content of the phosphor can be measured using, for example, a carbon sulfur analyzer EMIA-520 (manufactured by Horiba, Ltd.).

(Oxygen content)
The phosphor in which the base material of the present invention is a nitride usually has an oxygen content of 5% by weight or less, preferably 3.5% by weight or less, more preferably 0.5% by weight or less. When the phosphor of the present invention is a phosphor based on nitride and the oxygen content is higher than the above range, the emission intensity may be lowered or the emission spectrum may be shifted.
The oxygen content can be measured using, for example, an oxygen / nitrogen analyzer TC430 (manufactured by LECO) or a solid oxygen / nitrogen analyzer EMGA550 / EF610 (manufactured by Horiba).
In addition, the phosphor of the present invention is most preferable when the nitride is used as a base and the carbon content and the oxygen content are both 0.5% by weight or less because the emission intensity tends to increase.

The oxygen content and the carbon content are considered to depend not only on the raw material compound but also on the firing conditions such as the firing temperature, time, and atmosphere (oxygen concentration in the atmosphere, etc.). Therefore, in addition to using the C-containing raw material compound as a phosphor raw material, it is necessary to fire under appropriate firing conditions. For example, when the oxygen concentration in the firing atmosphere is lowered, the carbon content of the phosphor may increase. It is preferable to select firing conditions such that both the carbon content and the oxygen content of the phosphor are small.
The composition, emission color, and excitation light of the phosphor of the present invention are not particularly limited, and a desired phosphor can be obtained by adjusting the composition and the like.

(composition)
The phosphor of the present invention may contain Si element. Si nitrides are stable, and silicon-containing nitrides that inherit their properties are preferred as the host crystal of the phosphor.
Moreover, the phosphor of the present invention may further contain at least one of the periodic table group 2 elements. This is because it becomes easy to substitute (or dissolve) with rare earth elements such as Eu ²⁺ and Ce ^{3+ which} are preferable as the activating element.

(Example of phosphor)
Although there is no restriction | limiting in particular in the nitride crystal | crystallization used as the base material of the fluorescent substance of this invention, The following crystal is mentioned as a preferable example.
CaAlSiN ₃ , (Mg, Ca, Sr, Ba) Al SiN ₃ ,
Sr ₂ Si ₅ N ₈ , (Mg, Ca, Sr, Ba) ₂ Si ₅ N ₈ ,
(Mg, Ca, Sr, Ba) SiN ₂ ,
BaYSi ₄ N ₇ , (Ca, Sr, Ba) (La, Gd, Y, Lu, Sc) Si ₄ N ₇ ,
(La, Gd, Y) Si ₃ N ₅ ,
(La, Gd, Y) ₃ Si ₆ N ₁₁ ,
(La, Gd, Y, Lu, Sc) ₂ Si ₄ N ₆ C,
(La, Gd, Y, Lu , Sc) Al (Si 6-z Al z) N 10-z O z ( where, 0 <z <3),
(Ca, Sr, Ba) Si ₇ N ₁₀

  Among the above, a crystal in which a part of Si is replaced with Al and Ga and a part of nitrogen is replaced with oxygen is also a preferable example.

[2-2. Use of phosphor]
The phosphor of the present invention can be used for any application that uses the phosphor. In particular, taking advantage of the fact that it can be excited by blue light or near-ultraviolet light, various light emitting devices (see “ The light-emitting device of the invention ") can be suitably used. By adjusting the types and usage ratios of the phosphors to be combined, light emitting devices having various emission colors can be manufactured.

  For example, when the phosphor of the present invention is a red phosphor, a white light emitting device can be manufactured by combining an excitation light source that emits blue light and a green phosphor (phosphor that emits green fluorescence). In this case, the emission color can be changed to a desired emission color by adjusting the emission peak wavelength of the phosphor of the present invention or the green phosphor. For example, it is possible to realize a light emitting device that is extremely excellent in red color rendering and a light emitting device that emits light of a light bulb color (warm white). Further, depending on the emission color of the phosphor of the present invention and the emission color of the phosphor to be combined, an emission spectrum similar to the emission spectrum of so-called pseudo white (for example, the emission color of a light emitting device combining a blue LED and a yellow phosphor) may be obtained. It can also be obtained. In addition, a red phosphor (for example, the phosphor of the present invention emits red light), a blue phosphor (a phosphor that emits blue fluorescence), and a green phosphor are used as an excitation light source that emits near-ultraviolet light. Even when combined, a white light emitting device can be manufactured.

  The emission color of the light-emitting device is not limited to white, and if necessary, a yellow phosphor (phosphor that emits yellow fluorescence), a blue phosphor, a green phosphor, an orange to red phosphor, or the like can be combined for fluorescence. A light-emitting device that emits light in an arbitrary color can be manufactured by adjusting the type and use ratio of the body. The light-emitting device thus obtained can be used as a light-emitting portion (particularly a liquid crystal backlight) or an illumination device of an image display device.

[3. Phosphor-containing composition]
The phosphor-containing composition of the present invention contains the phosphor of the present invention and a liquid medium. When the phosphor of the present invention is used for a light emitting device or the like, it is preferably used in a form dispersed in a liquid medium.

The liquid medium that can be used in the phosphor-containing composition of the present invention is a liquid medium that exhibits liquid properties under the desired use conditions, and that suitably disperses the phosphor of the present invention and does not cause undesirable reactions. If there is, it is possible to select an arbitrary one according to the purpose. Examples of the liquid medium include a thermosetting resin and a photocurable resin before curing, and examples thereof include an addition reaction type silicone resin, a condensation reaction type silicone resin, a modified silicone resin, and an epoxy resin. In addition, a solution obtained by hydrolytic polymerization of a solution containing an inorganic material, for example, a ceramic precursor polymer or a metal alkoxide by a sol-gel method can be used. These liquid media may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and a ratio. In addition, an organic solvent can be contained in the liquid medium.
In particular, as the liquid medium, various materials as sealing materials described later are preferably used.

  The amount of the liquid medium used may be appropriately adjusted according to the application, etc., but in general, the weight ratio of the liquid medium to the phosphor of the present invention is usually 3% by weight or more, preferably 5% by weight or more, Moreover, it is 30 weight% or less normally, Preferably it is the range of 15 weight% or less. If the amount of the liquid medium is too small, light emission from the phosphor becomes too strong and the luminance may be lowered. If too much, the light emission from the phosphor becomes too weak and the luminance may be lowered.

In addition to the phosphor of the present invention and the liquid medium, the phosphor-containing composition of the present invention may contain other optional components depending on its use and the like. Examples of other components include a diffusing agent, a thickener, a bulking agent, and an interference agent. Specifically, silica-based fine powder such as Aerosil, alumina and the like can be mentioned.
In addition, these other components may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and ratios.

[4. Light emitting device]
The light-emitting device of the present invention includes a first light-emitting body and a second light-emitting body that emits visible light when irradiated with light from the first light-emitting body, and the second light-emitting body is the above-described book. It contains at least one of the phosphors of the invention as a first phosphor.

[4-1. First luminous body]
The 1st light-emitting body in the light-emitting device of this invention light-emits the light which excites the 2nd light-emitting body mentioned later. The light emission wavelength of the first light emitter is not particularly limited as long as it overlaps with the absorption wavelength of the second light emitter described later, and a light emitter having a wide light emission wavelength region can be used. Usually, an illuminant having an emission wavelength from the near-ultraviolet region to the blue region is used, and specific values are usually 300 nm or more, preferably 330 nm or more, and usually 500 nm or less, preferably 480 nm or less. A luminescent material is used. As the first light emitter, a semiconductor light emitting element is generally used. Specifically, a light emitting diode (hereinafter abbreviated as “LED” as appropriate) and a semiconductor laser diode (semiconductor laser diode). Hereinafter, abbreviated as “LD” as appropriate) can be used. In addition, as a light-emitting body that can be used as the first light-emitting body, an organic electroluminescence light-emitting element, an inorganic electroluminescence light-emitting element, and the like can be given. However, what can be used as a 1st light-emitting body is not restricted to what is illustrated by this specification.

Among these, as the first light emitter, a GaN LED or LD using a GaN compound semiconductor is preferable. This is because GaN-based LEDs and LDs have significantly higher light emission output and external quantum efficiency than SiC-based LEDs that emit light in this region, and are extremely bright with very low power when combined with the phosphor. This is because light emission can be obtained. For example, for a current load of 20 mA, GaN-based LEDs and LDs usually have a light emission intensity 100 times or more that of SiC-based. A GaN-based LED or LD preferably has an Al _x Ga _Y N light emitting layer, a GaN light emitting layer, or an In _x Ga _Y N light emitting layer. Among GaN-based LEDs, those having an In _X Ga _Y N light-emitting layer are particularly preferable because the emission intensity is very strong, and in GaN-based LDs, the multiple quantum of the In _X Ga _Y N layer and the GaN layer is preferred. A well structure is particularly preferable because the emission intensity is very strong.

  In the above, the value of X + Y is usually a value in the range of 0.8 to 1.2. In the GaN-based LED, those in which the light emitting layer is doped with Zn or Si or those without a dopant are preferable for adjusting the light emission characteristics.

A GaN-based LED has these light-emitting layer, p-layer, n-layer, electrode, and substrate as basic components, and the light-emitting layer is composed of n-type and p-type Al _x Ga _y N layers, GaN layers, or In _x. Those having a heterostructure sandwiched between Ga _Y N layers and the like are preferable because of high light emission efficiency, and those having a heterostructure of a quantum well structure are more preferable because of high light emission efficiency.

[4-2. Second luminous body]
The second light emitter in the light emitting device of the present invention is a light emitter that emits visible light when irradiated with light from the first light emitter described above, and contains the phosphor of the present invention as the first phosphor. In addition, a second phosphor to be described later is contained as appropriate according to the application. Further, for example, the second light emitter is configured by dispersing the first and second phosphors in a sealing material.

<4-2-1. First phosphor>
The first phosphor is not particularly limited as long as it is a phosphor produced by the production method of the present invention, that is, the phosphor of the present invention. Any one of the phosphors of the present invention may be used alone, or two or more thereof may be used in any combination and ratio.

<4-2-2. Second phosphor>
The second phosphor is a phosphor produced by a method other than the production method of the present invention, and there is no limitation on the composition, emission color, etc., and one of these may be used alone, or two or more may be used. It may be used. The second phosphor may be a phosphor having an emission peak wavelength different from that of the first phosphor or an equivalent phosphor. Usually, the second phosphor has an emission peak wavelength different from that of the first phosphor. A second phosphor is used to adjust the color of light emitted by the second phosphor.
Below, the fluorescent substance which can be used as a 2nd fluorescent substance is illustrated.
The following are merely examples, and phosphors that can be used in the present invention are not limited to these. In the present specification, phosphors that differ only in part of the structure are omitted as appropriate. For example, “Y ₂ SiO ₅ : Ce ³⁺ ”, “Y ₂ SiO ₅ : Tb ³⁺ ” and “Y ₂ SiO ₅ : Ce ³⁺ , Tb ³⁺ ” are changed to “Y ₂ SiO ₅ : Ce ³⁺ , Tb”. ³⁺ ”,“ La ₂ O ₂ S: Eu ”,“ Y ₂ O ₂ S: Eu ”and“ (La, Y) ₂ O ₂ S: Eu ”are changed to“ (La, Y) ₂ O ₂ S: “Eu” collectively. In this case, the total of the elements in () is 1 mol. Omitted parts are separated by commas (,).

(Orange to red phosphor)
When an orange or red phosphor is used as the second phosphor, any orange or red phosphor can be used as long as the effects of the present invention are not significantly impaired. In this case, the emission peak wavelength of the orange or red phosphor is preferably in the wavelength range of usually 580 nm or more, preferably 585 nm or more, and usually 780 nm or less, preferably 700 nm or less. Examples of such orange to red phosphors are europium expressed by (Mg, Ca, Sr, Ba) ₂ Si ₅ N ₈ : Eu, which is composed of broken particles having a red fracture surface and emits light in the red region. The activated alkaline earth silicon nitride-based phosphor is composed of growing particles having a substantially spherical shape as a regular crystal growth shape, and emits light in the red region (Y, La, Gd, Lu) ₂ O ₂ S: Examples include europium-activated rare earth oxychalcogenide phosphors represented by Eu.

  Furthermore, the oxynitride and / or acid containing at least one element selected from the group consisting of Ti, Zr, Hf, Nb, Ta, W, and Mo described in JP-A-2004-300247 A phosphor containing a sulfide or a phosphor containing an oxynitride having an alpha sialon structure in which a part or all of the Al element is substituted with a Ga element can also be used in this embodiment. These are phosphors containing oxynitride and / or oxysulfide.

Other red phosphors include Eu-activated oxysulfide phosphors such as (La, Y) ₂ O ₂ S: Eu, Y (V, P) O ₄ : Eu, Y ₂ O ₃ : Eu, etc. Eu-activated oxide phosphors of (Ba, Sr, Ca, Mg) ₂ SiO ₄ : Eu, Mn, (Ba, Mg) ₂ SiO ₄ : Eu, Mn-activated silicate phosphors such as Eu, Mn, Eu-activated tungstate phosphors such as LiW ₂ O ₈ : Eu, LiW ₂ O ₈ : Eu, Sm, Eu ₂ W ₂ O ₉ , Eu ₂ W ₂ O ₉ : Nb, Eu ₂ W ₂ O ₉ : Sm Eu-activated sulfide phosphors such as (Ca, Sr) S: Eu, Eu-activated aluminate phosphors such as YAlO ₃ : Eu, LiY ₉ (SiO ₄ ) ₆ O ₂ : Eu, Ca ₂ Y _{8 (SiO 4) 6 O 2:} Eu, (Sr, Ba, Ca) 3 SiO 5: Eu, Sr 2 BaSiO 5: Eu -activated silicate phosphors such as Eu, ( _{, Gd) 3 Al 5 O 12} : Ce, (Tb, Gd) 3 Al 5 O 12: Ce -activated aluminate phosphor such as Ce, (Mg, Ca, Sr , Ba) 2 Si 5 N 8: Eu (Mg, Ca, Sr, Ba) SiN ₂ : Eu, (Mg, Ca, Sr, Ba) Eu-activated nitride phosphors such as AlSiN ₃ : Eu, (Mg, Ca, Sr, Ba) AlSiN ₃ : Ce-activated nitride phosphors such as Ce, (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu, Mn-activated halophosphate phosphors such as Eu and Mn, Ba ₃ MgSi ₂ O ₈ : Eu, Mn, (Ba, Sr, Ca, Mg) ₃ (Zn, Mg) Si ₂ O ₈ : Eu, Mn activated silicate phosphor such as Eu, Mn, 3.5MgO · 0.5MgF ₂ · GeO _2: Mn activated germanate salt phosphors such as Mn, Eu Tsukekatsusan nitride firefly such Eu-activated α-sialon Body, (Gd, Y, Lu, La) 2 O 3: Eu, Eu Bi, etc., Bi-activated oxide phosphor, (Gd, Y, Lu, La) 2 O 2 S: Eu, Eu Bi, etc. Bi-activated oxysulfide phosphor, (Gd, Y, Lu, La) VO ₄ : Eu such as Eu and Bi, Bi-activated vanadate phosphor, SrY ₂ S ₄ : Eu such as Eu and Ce, Ce-activated sulfide phosphor, Ce-activated sulfide phosphor such as CaLa ₂ S ₄ : Ce, (Ba, Sr, Ca) MgP ₂ O ₇ : Eu, Mn, (Sr, Ca, Ba, Mg, Zn) ) ₂ P ₂ O ₇ : Eu, Mn activated phosphor phosphor such as Eu, Mn, (Y, Lu) ₂ WO ₆ : Eu, Mo activated tungstate phosphor such as Eu, Mo, (Ba , Sr, Ca) _x Si _{y Nz} : Eu, Ce (where x, y, z represent an integer of 1 or more. Eu, Ce activated nitride phosphors such as (Ca, Sr, Ba, Mg) ₁₀ (PO ₄ ) ₆ (F, Cl, Br, OH) ₂ : Eu, Mn activated halolin such as Eu, Mn Salt phosphor, ((Y, Lu, Gd, Tb) _1-xy Sc _x Ce _y ) ₂ (Ca, Mg) _1-r (Mg, Zn) _{2 + r} Si _zq Ge _q O _{12 + δ} It is also possible to use a Ce-activated silicate phosphor or the like.

  Examples of red phosphors include β-diketonates, β-diketones, aromatic carboxylic acids, red organic phosphors composed of rare earth element ion complexes having an anion such as Bronsted acid as a ligand, and perylene pigments (for example, Dibenzo {[f, f ′]-4,4 ′, 7,7′-tetraphenyl} diindeno [1,2,3-cd: 1 ′, 2 ′, 3′-lm] perylene), anthraquinone pigment, Lake pigments, azo pigments, quinacridone pigments, anthracene pigments, isoindoline pigments, isoindolinone pigments, phthalocyanine pigments, triphenylmethane basic dyes, indanthrone pigments, indophenol pigments, It is also possible to use a cyanine pigment or a dioxazine pigment.

Among the red phosphors, those having a peak wavelength in the range of 580 nm or more, preferably 590 nm or more, and 620 nm or less, preferably 610 nm or less can be suitably used as the orange phosphor. Examples of such orange phosphors include Eu-activated silicate phosphors such as (Sr, Ba, Ca) ₃ SiO ₅ : Eu, Sr ₂ BaSiO ₅ : Eu, (Sr, Mg) ₃ (PO ₄ ). ₂ : Sn-activated phosphate phosphor such as Sn ²⁺ .
Any one of the red phosphors exemplified above may be used alone, or two or more may be used in any combination and ratio.

Among the above examples, as the red phosphor, (Ca, Sr, Ba) AlSiN ₃ : Eu, (Ca, Sr, Ba) AlSiN ₃ : Ce, (La, Y) ₂ O ₂ S: Eu are preferable, (Sr, Ca) AlSiN ₃ : Eu and (La, Y) ₂ O ₂ S: Eu are particularly preferred.

Of the above examples, (Sr, Ba) ₃ SiO ₅ : Eu is preferable as the orange phosphor.

(Green phosphor)
When a green phosphor is used as the second phosphor, any green phosphor can be used as long as the effects of the present invention are not significantly impaired. At this time, the emission peak wavelength of the green phosphor is usually in the wavelength range of 490 nm or more, preferably 510 nm or more, more preferably 515 nm or more, and usually 560 nm or less, preferably 540 nm or less, more preferably 535 nm or less. Is preferred.

The green phosphor, for example, consist of fractured particles having a fractured surface and performs light emission in the green region (Mg, Ca, Sr, Ba ) Si 2 O 2 N 2: Europium-activated alkaline earth represented by Eu A silicon oxynitride phosphor, composed of fractured particles having a fractured surface, emits light in the green region (Ba, Ca, Sr, Mg) ₂ SiO ₄ : europium activated alkaline earth silicate fluorescence represented by Eu Examples include the body.

Other green phosphors include Eu-activated aluminate phosphors such as Sr ₄ Al ₁₄ O ₂₅ : Eu, (Ba, Sr, Ca) Al ₂ O ₄ : Eu, and (Sr, Ba) Al _{2. Si 2 O 8: Eu, (} Ba, Mg) 2 SiO 4: Eu, (Ba, Sr, Ca, Mg) 2 SiO 4: Eu, (Ba, Sr, Ca) 2 (Mg, Zn) Si 2 O 7 : Eu, (Ba, Ca, Sr, Mg) ₉ (Sc, Y, Lu, Gd) ₂ (Si, Ge) ₆ O ₂₄ : Eu-activated silicate phosphor such as Eu, Y ₂ SiO ₅ : Ce, Ce, Tb activated silicate phosphor such as Tb, Sr ₂ P ₂ O ₇ —Sr ₂ B ₂ O ₅ : Eu activated borate phosphate phosphor such as Eu, Sr ₂ Si ₃ O ₈ -2SrCl ₂ : Eu-activated halo silicate phosphor such as Eu, Zn ₂ SiO _4: Mn-activated silicate phosphors such as _{Mn, CeMgAl 11 O 19: Tb} , ₃ Al ₅ O _12: Tb-activated aluminate phosphors such as _{Tb, Ca 2 Y 8 (SiO} 4) 6 O 2: Tb, La 3 Ga 5 SiO 14: Tb -activated silicate phosphors such as Tb, (Sr, Ba, Ca) Ga ₂ S ₄ : Eu, Tb, Sm activated thiogallate phosphors such as Eu, Tb, Sm, Y ₃ (Al, Ga) ₅ O ₁₂ : Ce, (Y, Ga, Tb, La, Sm, Pr, Lu) ₃ (Al, Ga) ₅ O ₁₂ : Ce-activated aluminate phosphor such as Ce, Ca ₃ Sc ₂ Si ₃ O ₁₂ : Ce, Ca ₃ (Sc, Mg, Na, Li) ₂ Si ₃ O ₁₂ : Ce activated silicate phosphor such as Ce, CaSc ₂ O ₄ : Ce activated oxide phosphor such as Ce, SrSi ₂ O ₂ N ₂ : Eu, (Mg, Sr, Ba _{, Ca) Si 2 O 2 N} 2: Eu, Eu Tsukekatsusan nitride phosphor such as Eu-activated β-sialon, BaMgAl ₁₀ O _17: E , Eu such as Mn, Mn-activated aluminate phosphor, SrAl ₂ O _4: Eu-activated aluminate phosphor such as Eu, (La, Gd, Y ) 2 O 2 S: Tb -activated and Tb such Oxysulfide phosphors, Ce, Tb activated phosphate phosphors such as LaPO ₄ : Ce, Tb, sulfide phosphors such as ZnS: Cu, Al, ZnS: Cu, Au, Al, (Y, Ga, Lu, Sc, La) BO ₃ : Ce, Tb, Na ₂ Gd ₂ B ₂ O ₇ : Ce, Tb, (Ba, Sr) ₂ (Ca, Mg, Zn) B ₂ O ₆ : K, Ce, Tb, etc. Ce, Tb activated borate phosphor, Ca ₈ Mg (SiO ₄ ) ₄ Cl ₂ : Eu, Mn activated halosilicate phosphor such as Eu, Mn, (Sr, Ca, Ba) (Al, Ga, In) ₂ S ₄ : Eu-activated thioaluminate phosphor such as Eu or thiogallate phosphor, (Ca, Sr) ₈ (Mg, Zn) (SiO ₄ ) ₄ Cl ₂ : Eu, Mn activated halosilicate phosphors such as Eu and Mn, MSi ₂ O ₂ N ₂ : Eu, M ₃ Si ₆ O ₉ N ₄ : Eu, M ₂ Si ₇ O ₁₀ N ₄ : Eu (where M represents an alkaline earth metal element) It is also possible to use Eu-activated oxynitride phosphors such as

  In addition, as the green phosphor, it is also possible to use a pyridine-phthalimide condensed derivative, a benzoxazinone-based, a quinazolinone-based, a coumarin-based, a quinophthalone-based, a naltalimide-based fluorescent pigment, or an organic phosphor such as a terbium complex. is there.

  Any one of the green phosphors exemplified above may be used alone, or two or more may be used in any combination and ratio.

(Blue phosphor)
When a blue phosphor is used as the second phosphor, any blue phosphor can be used as long as the effects of the present invention are not significantly impaired. At this time, the emission peak wavelength of the blue phosphor is usually in the wavelength range of 420 nm or more, preferably 430 nm or more, more preferably 440 nm or more, and usually 490 nm or less, preferably 470 nm or less, more preferably 460 nm or less. Is preferred.

As such a blue phosphor, a europium activated barium magnesium aluminate system represented by BaMgAl ₁₀ O ₁₇ : Eu which is composed of growing particles having a substantially hexagonal shape as a regular crystal growth shape and emits light in a blue region. Europium activated halo represented by (Ca, Sr, Ba) ₅ (PO ₄ ) ₃ Cl: Eu, which is composed of phosphors and growing particles having a substantially spherical shape as a regular crystal growth shape, and emits light in the blue region. Calcium phosphate-based phosphor, composed of growing particles having an approximately cubic shape as a regular crystal growth shape, emits light in the blue region, and is activated by europium represented by (Ca, Sr, Ba) ₂ B ₅ O ₉ Cl: Eu It is composed of alkaline earth chloroborate phosphors and fractured particles having fractured surfaces, and emits light in the blue-green region (S _{, Ca, Ba) Al 2 O} 4: Eu or _{(Sr, Ca, Ba) 4} Al 14 O 25: activated alkaline earth with europium aluminate-based phosphor such as represented by Eu and the like.

Other blue phosphors include Sn-activated phosphate phosphors such as Sr ₂ P ₂ O ₇ : Sn, (Sr, Ca, Ba) Al ₂ O ₄ : Eu or (Sr, Ca, Ba). ₄ Al ₁₄ O ₂₅ : Eu, BaMgAl ₁₀ O ₁₇ : Eu, BaAl ₈ O ₁₃ : Eu-activated aluminate phosphors such as Eu, SrGa ₂ S ₄ : Ce, CaGa ₂ S ₄ : Ce-activated such as Ce Thiogallate phosphor, (Ba, Sr, Ca) MgAl ₁₀ O ₁₇ : Eu, BaMgAl ₁₀ O ₁₇ : Eu-activated aluminate phosphor such as Eu, Tb, Sm, (Ba, Sr, Ca) MgAl ₁₀ O ₁₇ : Eu, Mn activated aluminate phosphor such as Eu, Mn, (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu, (Ba, Sr, Ca) ₅ (PO ₄ ) ₃ (Cl, F, Br, OH): Eu-activated halolin such as Eu, Mn, Sb _{Phosphor, BaAl 2 Si 2 O 8:} Eu, (Sr, Ba) 3 MgSi 2 O 8: Eu -activated silicate phosphors such as _{Eu, Sr 2 P 2 O 7} : Eu -activated phosphate such as Eu Salt phosphors, sulfide phosphors such as ZnS: Ag, ZnS: Ag, Al, Ce activated silicate phosphors such as Y ₂ SiO ₅ : Ce, tungstate phosphors such as CaWO ₄ , (Ba, Sr) _{, Ca) BPO 5: Eu,} Mn, (Sr, Ca) 10 (PO 4) 6 · nB 2 O 3: Eu, 2SrO · 0.84P 2 O 5 · 0.16B 2 O 3: Eu or the like of Eu, Mn-activated borate phosphate phosphor, Eu-activated halosilicate phosphor such as Sr ₂ Si ₃ O ₈ .2SrCl ₂ : Eu, SrSi ₉ Al ₁₉ ON ₃₁ : Eu, EuSi ₉ Al ₁₉ ON _{31 and} other Eu It is also possible to use an activated oxynitride phosphor or the like.

  In addition, as the blue phosphor, for example, naphthalic acid imide-based, benzoxazole-based, styryl-based, coumarin-based, pyrazoline-based, triazole-based compound fluorescent dyes, thulium complexes and other organic phosphors can be used. .

Among the above examples, as the blue phosphor, BaMgAl ₁₀ O ₁₇ : Eu, (Ba, Ca, Mg) ₂ SiO ₄ : Eu, (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu is preferred, and BaMgAl ₁₀ O ₁₇ : Eu is particularly preferred.

  Any one of the blue phosphors exemplified above may be used alone, or two or more may be used in any combination and ratio.

(Yellow phosphor)
When a yellow phosphor is used as the second phosphor, any blue phosphor can be used as long as the effects of the present invention are not significantly impaired. At this time, the emission peak wavelength of the yellow phosphor is usually in the wavelength range of 530 nm or more, preferably 540 nm or more, more preferably 550 nm or more, and usually 620 nm or less, preferably 600 nm or less, more preferably 580 nm or less. Is preferred.

Examples of such yellow phosphors include various oxide-based, nitride-based, oxynitride-based, sulfide-based, and oxysulfide-based phosphors.
In particular, RE ₃ M ₅ O ₁₂ : Ce (where RE represents at least one element selected from the group consisting of Y, Tb, Gd, Lu, and Sm, and M represents Al, Ga, and Sc. And M ^a ₃ M ^b ₂ M ^c ₃ O ₁₂ : Ce (where M ^a is a divalent metal element and M ^b is a trivalent metal element) , M ^c represents a tetravalent metal element.) A garnet phosphor having a garnet structure represented by AE ₂ M ^d O ₄ : Eu (where AE is Ba, Sr, Ca, Mg, and And at least one element selected from the group consisting of Zn, M ^d represents Si and / or Ge, etc.) and the oxygen of the constituent elements of the phosphors of these systems Oxynitride phosphor, part of which is replaced with nitrogen, AEAlSiN ₃ : C e (wherein AE represents at least one element selected from the group consisting of Ba, Sr, Ca, Mg, and Zn) and activated with Ce such as a nitride-based phosphor having a CaAlSiN ₃ structure. And Eu-activated oxynitride phosphors such as (Mg, Ca, Sr, Ba) Si ₂ N ₂ O ₂ : Eu.

Other examples of yellow phosphors include sulfide-based fluorescence such as CaGa ₂ S ₄ : Eu, (Ca, Sr) Ga ₂ S ₄ : Eu, (Ca, Sr) (Ga, Al) ₂ S ₄ : Eu. It is also possible to use a phosphor activated by Eu such as an oxynitride phosphor having a SiAlON structure such as a body, Cax (Si, Al) ₁₂ (O, N) ₁₆ : Eu.

  Examples of yellow phosphors include brilliant sulfoflavine FF (Color Index Number 56205), basic yellow HG (Color Index Number 46040), eosine (Color Index Number 45e 380d) Etc. can also be used.

  Any one of the yellow phosphors exemplified above may be used alone, or two or more may be used in any combination and ratio.

In addition, as a 2nd fluorescent substance, 1 type of fluorescent substance may be used independently, and 2 or more types of fluorescent substance may be used together by arbitrary combinations and a ratio. Further, the ratio between the first phosphor and the second phosphor is also arbitrary as long as the effects of the present invention are not significantly impaired. Therefore, the usage amount of the second phosphor, the combination of phosphors used as the second phosphor, and the ratio thereof may be arbitrarily set according to the use of the light emitting device.

<4-2-3. Physical properties of second phosphor>
The weight median diameter (D ₅₀ ) of the second phosphor used in the light emitting device of the present invention is preferably in the range of usually 10 μm or more, especially 15 μm or more, and usually 30 μm or less, especially 20 μm or less. When the weight median diameter is too small, the luminance is lowered and the phosphor particles tend to aggregate. On the other hand, if the weight median diameter is too large, there is a tendency for coating unevenness and blockage of the dispenser to occur.

<4-2-4. Selection of second phosphor>
In the light emitting device of the present invention, the presence / absence and type of the second phosphor described above may be appropriately selected according to the use of the light emitting device. For example, when the light-emitting device of the present invention is configured as a red light-emitting device, only the first phosphor that is a red phosphor may be used, and the use of the second phosphor is usually unnecessary. .

  On the other hand, when the light emitting device of the present invention is configured as a white light emitting device, the first light emitter, the first phosphor, and the second phosphor are provided so as to obtain desired white light. What is necessary is just to combine appropriately. Specifically, examples of preferable combinations of the first light emitter, the first phosphor, and the second phosphor in the case where the light emitting device of the present invention is configured as a white light emitting device include the following: (I) to (v) may be mentioned.

(I) When the phosphor of the present invention is a red phosphor (i-1) A blue phosphor (blue LED or the like) is used as the first phosphor, and a red phosphor (the present invention) is used as the first phosphor. And the green phosphor is used as the second phosphor. In this case, as the green phosphor, (Ba, Sr, Ca, Mg) ₂ SiO ₄ : Eu, (Sr, Ba, Ca) Ga ₂ S ₄ : Eu, Tb, Sm, Y ₃ (Al, Ga) _{5 O 12: Ce, (Y,} Ga, Tb, La, Sm, Pr, Lu) 3 (Al, Ga) 5 O 12: Ce, Ca 3 Sc 2 Si 3 O 12: Ce, Ca 3 (Sc, Mg, Na, Li) ₂ Si ₃ O ₁₂ : Ce, CaSc ₂ O ₄ : Ce, SrSi ₂ O ₂ N ₂ : Eu, (Mg, Sr, Ba, Ca) Si ₂ O ₂ N ₂ : Eu, and Eu activation One or more green phosphors selected from the group consisting of β sialon are preferred.
(I-2) A near ultraviolet light emitter (near ultraviolet LED or the like) is used as the first light emitter, a red phosphor (such as the phosphor of the present invention) is used as the first phosphor, and the second fluorescence A blue phosphor and a green phosphor are used in combination. In this case, BaMgAl ₁₀ O ₁₇ : Eu is preferable as the blue phosphor. In addition, as the green phosphor, (Ba, Sr, Ca, Mg) ₂ SiO ₄ : Eu, (Sr, Ba, Ca) Ga ₂ S ₄ : Eu, Tb, Sm, SrSi ₂ O ₂ N ₂ : Eu, (Mg, Sr, Ba, Ca) One or two or more red phosphors selected from the group consisting of Si ₂ O ₂ N ₂ : Eu, Eu-activated β sialon, and BaMgAl ₁₀ O ₁₇ : Eu, Mn preferable. Among them, a near-ultraviolet LED, the phosphor of the present invention, BaMgAl ₁₀ O ₁₇ : Eu as a blue phosphor, and BaMgAl ₁₀ O ₁₇ : Eu, Mn and / or (Ca, Sr, Ba) Ga ₂ as a green phosphor. It is preferable to use a combination of S _{4 and} Eu.

(Ii) When the phosphor of the present invention is an orange phosphor (ii-1) A light emitter (blue LED or the like) is used as the first phosphor, and an orange phosphor (of the present invention) is used as the first phosphor. And a green phosphor is used in combination as the second phosphor. In this case, as the green phosphor, (Ba, Sr, Ca, Mg) ₂ SiO ₄ : Eu, (Sr, Ba, Ca) Ga ₂ S ₄ : Eu, Tb, Sm, Y ₃ (Al, Ga) _{5 O 12: Ce, (Y,} Ga, Tb, La, Sm, Pr, Lu) 3 (Al, Ga) 5 O 12: Ce, Ca 3 Sc 2 Si 3 O 12: Ce, Ca 3 (Sc, Mg, Na, Li) ₂ Si ₃ O ₁₂ : Ce, CaSc ₂ O ₄ : Ce, SrSi ₂ O ₂ N ₂ : Eu, (Mg, Sr, Ba, Ca) Si ₂ O ₂ N ₂ : Eu, and Eu activation β sialon is preferred. Such a light emitting device emits so-called pseudo white light.
(Ii-2) A near ultraviolet light emitter (near ultraviolet LED or the like) is used as the first light emitter, an orange phosphor (such as the phosphor of the present invention) is used as the first phosphor, and the second fluorescence. A blue phosphor and a green phosphor are used in combination. In this case, BaMgAl ₁₀ O ₁₇ : Eu is preferable as the blue phosphor. In addition, as the green phosphor, (Ba, Sr, Ca, Mg) ₂ SiO ₄ : Eu, (Sr, Ba, Ca) Ga ₂ S ₄ : Eu, Tb, Sm, SrSi ₂ O ₂ N ₂ : Eu, (Mg, Sr, Ba, Ca) Si ₂ O ₂ N ₂ : Eu, Eu-activated β sialon, and BaMgAl ₁₀ O ₁₇ : Eu, Mn are preferred. Such a light emitting device emits so-called pseudo white light.
(Ii-3) Although both (ii-1) and (ii-2) are pseudo white, color rendering is improved by combining them with a red phosphor. In this case, as the red phosphor, one or more red phosphors selected from the group consisting of (Sr, Ca) AlSiN ₃ : Eu and (Ca, Sr, Ba) ₂ Si ₅ N ₈ : Eu are used. Is preferred.

(Iii) When the phosphor of the present invention is a green phosphor (iii-1) A blue phosphor (such as a blue LED) is used as the first phosphor, and a green phosphor (the present invention) is used as the first phosphor. And a red phosphor is used as the second phosphor. In this case, as the red phosphor, one or more red phosphors selected from the group consisting of (Sr, Ca) AlSiN ₃ : Eu and (Ca, Sr, Ba) ₂ Si ₅ N ₈ : Eu are used. Is preferred.
(Iii-2) A near ultraviolet light emitter (near ultraviolet LED or the like) is used as the first light emitter, a green phosphor (such as the phosphor of the present invention) is used as the first phosphor, and the second fluorescence A blue phosphor and a red phosphor are used in combination. In this case, BaMgAl ₁₀ O ₁₇ : Eu is preferable as the blue phosphor. The red phosphor may be one selected from the group consisting of (Sr, Ca) AlSiN ₃ : Eu, La ₂ O ₂ S: Eu, and (Ca, Sr, Ba) ₂ Si ₅ N ₈ : Eu or Two or more red phosphors are preferred. Among them, it is preferable to use a near ultraviolet LED, the phosphor of the present invention, BaMgAl ₁₀ O ₁₇ : Eu as a blue phosphor, and (Sr, Ca) AlSiN ₃ : Eu as a red phosphor.
(Iii-3) A blue light emitter (blue LED or the like) is used as the first light emitter, a green phosphor (such as the phosphor of the present invention) is used as the first phosphor, and the second phosphor is used. An orange phosphor is used. In this case, (Sr, Ba) ₃ SiO ₅ : Eu is preferable as the orange phosphor.

(Iv) When the phosphor of the present invention is a blue phosphor (iv-1) A near ultraviolet light emitter (near ultraviolet LED or the like) is used as the first light emitter, and a blue phosphor ( The phosphor of the present invention is used, and a green phosphor and a red phosphor are used in combination as the second phosphor. In this case, as the green phosphor, (Ba, Sr, Ca, Mg) ₂ SiO ₄ : Eu, (Sr, Ba, Ca) Ga ₂ S ₄ : Eu, Tb, Sm, SrSi ₂ O ₂ N ₂ : Eu , (Mg, Sr, Ba, Ca) Si ₂ O ₂ N ₂ : Eu, Eu-activated β sialon, and BaMgAl ₁₀ O ₁₇ : Eu, Mn are preferred. The red phosphor may be one selected from the group consisting of (Sr, Ca) AlSiN ₃ : Eu, La ₂ O ₂ S: Eu, and (Ca, Sr, Ba) ₂ Si ₅ N ₈ : Eu or Two or more red phosphors are preferred.
(Iv-2) A near ultraviolet light emitter (near ultraviolet LED or the like) is used as the first light emitter, a blue phosphor (the phosphor of the present invention) is used as the first phosphor, and the second fluorescence. A yellow phosphor is used in combination. In this case, as the yellow phosphor, RE ₃ M ₅ O ₁₂ : Ce (where RE represents at least one element selected from the group consisting of Y, Tb, Gd, Lu, and Sm, and M represents , Al, Ga, and Sc represents at least one element selected from the group consisting of: M ^a ₃ M ^b ₂ M ^c ₃ O ₁₂ : Ce (where M ^a is a divalent metal element, M ^b is a trivalent metal element, ^{M c} represents a tetravalent metallic _{^{element), AE 2 M d O 4}} :. Eu ( where, AE is, Ba, Sr, Ca, Mg , and from the group consisting of Zn Represents at least one element selected, and M ^d represents Si and / or Ge.) And (Mg, Ca, Sr, Ba) Si ₂ N ₂ O ₂ : Eu are preferable.

(V) When the phosphor of the present invention is a yellow phosphor (v-1) A blue phosphor (such as a blue LED) is used as the first phosphor, and a yellow phosphor (the present invention) is used as the first phosphor. Phosphor etc.). In this case, pseudo white light is emitted.
(V-2) A near ultraviolet light emitter (near ultraviolet LED or the like) is used as the first light emitter, a yellow phosphor (such as the phosphor of the present invention) is used as the first phosphor, and the second fluorescence. A blue phosphor is used as a body. In this case, BaMgAl ₁₀ O ₁₇ : Eu is preferable as the blue phosphor. In this case, pseudo white light is emitted.

<4-2-5. Sealing material>
The second light emitter is configured, for example, by dispersing the above-described first phosphor and the second phosphor used as necessary in a sealing material.
When a sealing material is used, it can be used after being sealed with a liquid silicone material or the like as described later and then cured by heat or light. As the sealing material used, an inorganic material and / or an organic material can be used.

  As the inorganic material, for example, a solution obtained by hydrolytic polymerization of a solution containing a metal alkoxide, a ceramic precursor polymer or a metal alkoxide by a sol-gel method, or a combination thereof, an inorganic material (for example, a siloxane bond) Inorganic materials having

  Examples of organic materials include thermoplastic resins, thermosetting resins, and photocurable resins. Specifically, for example, methacrylic resin such as polymethylmethacrylate; styrene resin such as polystyrene and styrene-acrylonitrile copolymer; polycarbonate resin; polyester resin; phenoxy resin; butyral resin; polyvinyl alcohol; Cellulose resins such as cellulose acetate butyrate; epoxy resins; phenol resins; silicone resins. In particular, when a high-power light-emitting device such as illumination is required, it is preferable to use a silicon-containing compound for the purpose of heat resistance and light resistance.

  A silicon-containing compound refers to a compound having a silicon atom in the molecule, organic materials such as polyorganosiloxane (silicone-based materials), inorganic materials such as silicon oxide, silicon nitride, and silicon oxynitride, and borosilicates and phosphosilicates. Examples thereof include glass materials such as salts and alkali silicates. Among these, silicone materials are preferable from the viewpoint of ease of handling.

(Silicone material)
The silicone material usually refers to an organic polymer having a siloxane bond as a main chain, and examples thereof include a compound represented by the general composition formula (1) and / or a mixture thereof.
(R ¹ R ² R ³ SiO _1/2 ) _M (R ⁴ R ⁵ SiO _2/2 ) _D (R ⁶ SiO _3/2 ) _T (SiO _4/2 ) _Q
... Formula (1)
Here, R ¹ to R ⁶ may be the same or different and are selected from the group consisting of an organic functional group, a hydroxyl group, and a hydrogen atom. M, D, T, and Q are 0 to less than 1 and satisfy M + D + T + Q = 1.
When a silicone material is used for sealing a semiconductor light emitting element, it can be used after being sealed with a liquid silicone material and then cured by heat or light.

(Types of silicone materials)
When silicone materials are classified according to the curing mechanism, silicone materials such as an addition polymerization curing type, a condensation polymerization curing type, an ultraviolet curing type, and a peroxide vulcanization type can be mentioned. Among these, addition polymerization curing type (addition type silicone resin), condensation curing type (condensation type silicone resin), and ultraviolet curing type are preferable. Hereinafter, the addition type silicone material and the condensation type silicone material will be described.

(Additional silicone material)
The addition-type silicone material refers to a material in which a polyorganosiloxane chain is crosslinked by an organic addition bond. A typical example is a compound having a Si—C—C—Si bond at a crosslinking point obtained by reacting vinylsilane and hydrosilane in the presence of an addition catalyst such as a Pt catalyst. As these, commercially available products can be used. Specific examples of addition polymerization curing type trade names include “LPS-1400”, “LPS-2410”, and “LPS-3400” manufactured by Shin-Etsu Chemical Co., Ltd.

(Condensation type silicone material)
Examples of the condensation type silicone material include a compound having a Si—O—Si bond obtained by hydrolysis and polycondensation of an alkylalkoxysilane at a crosslinking point.

  Specific examples include polycondensates obtained by hydrolysis and polycondensation of compounds represented by the following general formula (2) and / or (3) and / or oligomers thereof.

M ^{m +} X _n Y ¹ _mn (2)
(In the formula (2), M represents at least one element selected from silicon, aluminum, zirconium, and titanium, X represents a hydrolyzable group, and Y ¹ represents a monovalent organic group. M represents one or more integers representing the valence of M, and n represents one or more integers representing the number of X groups, provided that m ≧ n.

_{^{(M s + X t Y 1}} st) u Y 2 ··· (3)
(In Formula (3), M represents at least one element selected from silicon, aluminum, zirconium, and titanium, X represents a hydrolyzable group, and Y ¹ represents a monovalent organic group. Y ² represents a u-valent organic group, s represents an integer of 1 or more representing the valence of M, t represents an integer of 1 or more and s−1 or less, and u is 2 or more. Represents an integer.)

[4-3. Configuration of light emitting device]
The light-emitting device of the present invention is not particularly limited as long as it includes the first light-emitting body and the second light-emitting body described above, but usually the first light-emitting body described above on an appropriate frame. And a second light emitter. At this time, the second light emitter is excited by the light emission of the first light emitter (that is, the first and second phosphors are excited) to emit light, and the first light emitter emits light. And / or it arrange | positions so that light emission of a 2nd light-emitting body may be taken out outside. In this case, the first phosphor and the second phosphor are not necessarily mixed in the same layer. For example, the second phosphor is contained on the layer containing the first phosphor. For example, the phosphor may be contained in a separate layer for each color development of the phosphor, such as by stacking layers.

  In the light emitting device of the present invention, members other than the first light emitter, the second light emitter, and the frame described above may be used. For example, <4-2-5. Examples thereof include the sealing materials described in “Sealing Material>. As a specific example, the sealing material is used for the purpose of dispersing the second light emitter in the light emitting device, or for the purpose of bonding the first light emitter, the second light emitter and the frame. be able to.

  As the sealing material, for example, <4-2-5. The same materials as those exemplified as the constituent material of the second light emitter in the sealing material> can be used. Other examples of the sealing resin used usually include thermoplastic resins, thermosetting resins, and photocurable resins. Specifically, for example, methacrylic resin such as polymethylmethacrylate; styrene resin such as polystyrene and styrene-acrylonitrile copolymer; polycarbonate resin; polyester resin; phenoxy resin; butyral resin; polyvinyl alcohol; Cellulose resins such as cellulose acetate butyrate; epoxy resins; phenol resins; silicone resins. Further, an inorganic material such as a siloxane bond formed by solidifying a solution obtained by hydrolytic polymerization of a solution containing an inorganic material such as a metal alkoxide, ceramic precursor polymer or metal alkoxide by a sol-gel method, or a combination thereof. An inorganic material can be used.

[4-4. Embodiment of Light Emitting Device]
Hereinafter, the light-emitting device of the present invention will be described in more detail with reference to specific embodiments. However, the present invention is not limited to the following embodiments, and does not depart from the gist of the present invention. It can be implemented with arbitrary modifications.

  FIG. 1 is a diagram schematically showing a configuration of a light emitting device according to an embodiment of the present invention. The light emitting device 1 of the present embodiment absorbs a part of light emitted from the frame 2, a blue LED (first light emitter) 3 that is a light source, and the blue LED 3, and emits light having a wavelength different from that. It comprises a phosphor-containing part (second light emitter) 4.

  The frame 2 is a metal base for holding the blue LED 3 and the phosphor-containing portion 4. On the upper surface of the frame 2, a trapezoidal concave section (dent) 2A having an opening on the upper side in FIG. Thereby, since the frame 2 has a cup shape, the light emitted from the light emitting device 1 can have directivity, and the emitted light can be used effectively.

  A blue LED 3 is installed as a light source at the bottom of the recess 2 </ b> A of the frame 2. The blue LED 3 is an LED that emits blue light when supplied with electric power. Part of the blue light emitted from the blue LED 3 is absorbed as excitation light by the light-emitting substance (the first phosphor and the second phosphor) in the phosphor-containing part 4, and another part is The light is emitted from the light emitting device 1 in a predetermined direction.

  In addition, the blue LED 3 is installed at the bottom of the recess 2A of the frame 2 as described above. Here, the frame 2 and the blue LED 3 are bonded to each other by the adhesive 5, so that the blue LED 3 is attached to the frame 2. is set up.

  Further, a gold wire 6 for supplying power to the blue LED 3 is attached to the frame 2. That is, an electrode (not shown) provided on the upper surface of the blue LED 3 is connected by wire bonding using the wire 6, and power is supplied to the blue LED 3 by energizing the wire 6. The blue LED 3 emits blue light. One or a plurality of wires 6 are attached in accordance with the structure of the blue LED 3.

  Further, the concave portion 2A of the frame 2 is provided with a phosphor-containing portion 4 that absorbs part of the light emitted from the blue LED 3 and emits light having a different wavelength. The phosphor-containing part 4 is formed of a phosphor and a transparent resin (sealing material). The phosphor is a substance that is excited by blue light emitted from the blue LED 3 and emits light having a wavelength longer than that of the blue light. The phosphor constituting the phosphor-containing portion 4 may be a single type or a mixture of a plurality of colors, and the sum of the light emitted from the blue LED 3 and the light emitted from the phosphor light-emitting portion 4 is a desired color. Choose to be. The color is not limited to white, but may be yellow, orange, pink, purple, blue-green, or the like. Further, it may be an intermediate color between these colors and white. Here, for example, a red phosphor (first phosphor) and a green phosphor (second phosphor) made of the phosphor of the present invention are used as phosphors, and white light is emitted from the light emitting device. Suppose that

  The mold unit 7 functions as a lens for protecting the blue LED 3, the phosphor-containing unit 4, the wire 6 and the like from the outside and controlling the light distribution characteristics. For example, an epoxy resin can be used for the mold portion 7.

  Since the light emitting device of the present embodiment is configured as described above, when the blue LED 3 emits light, the green phosphor and the red phosphor in the phosphor light emitting section 4 are excited to emit light. As a result, the light emitting device emits white light composed of blue light emitted from the blue LED 3, green light emitted from the green phosphor, and red light emitted from the red phosphor.

The light-emitting device of the present invention is not limited to the above-described embodiment, and can be implemented with any changes without departing from the gist thereof.
For example, a surface-emitting type can be used as the first light emitter, and a film-like one can be used as the second light emitter. In this case, it is preferable to have a shape in which the film-shaped second light emitter is in direct contact with the light emitting surface of the first light emitter. In addition, contact here means producing the state which the 1st light-emitting body and the 2nd light-emitting body have touched exactly without passing air or gas. As a result, it is possible to avoid a light amount loss in which light from the first light emitter is reflected by the film surface of the second light emitter and oozes out, so that the light emission efficiency of the entire apparatus can be improved.

FIG. 2 is a schematic perspective view showing an example of a light emitting device in which a surface light emitting type is used as the first light emitter and a film-like one is applied as the second light emitter. In the light-emitting device 8 shown in FIG. 2, a surface-emitting GaN-based LD 10 as a first light-emitting body is provided on a substrate 9, and a film-shaped second light-emitting body 11 is formed on the surface-emitting GaN-based LD 10. Has been. Here, in order to create a state where they are in contact with each other, the LD 10 as the first light emitter and the second light emitter 11 are prepared separately, and their surfaces are brought into contact with each other by an adhesive or other means. Alternatively, the second light emitter 11 may be formed (molded) on the light emitting surface of the LD 10. As a result, the LD 11 and the second light emitter 11 can be brought into contact with each other.
According to the light-emitting device 8 having such a configuration, in addition to the same advantages as those of the above-described embodiment, it is possible to improve the light emission efficiency by avoiding the loss of light amount.

[4-5. Application of light emitting device]
The application of the light-emitting device of the present invention is not particularly limited, and can be used in various fields in which ordinary light-emitting devices are used. However, since the color reproduction range is wide and color rendering is high, the image It is particularly preferably used as a light source for a display device or a lighting device. In addition, when using the light-emitting device of this invention as a light source of an image display apparatus, using with a color filter is preferable. For example, when the image display device is a color image display device using color liquid crystal display elements, the light emitting device is used as a backlight, a light shutter using liquid crystal, and a color filter having red, green, and blue pixels; By combining these, an image display device can be formed.

  An example of a surface emitting illumination device 12 incorporating the light emitting device 1 shown in FIG. 1 is schematically shown in FIG. In the surface light emitting illumination device 12, a large number of light emitting devices 1 are provided on the bottom surface of a rectangular holding case 13 whose inner surface is light-opaque such as a white smooth surface, and a power source for driving the light emitting device 1 is provided on the outside thereof. And a circuit (not shown) are provided. In order to make the light emission uniform, a diffuser plate 14 such as a milky white acrylic plate is fixed to a portion corresponding to the lid portion of the holding case 13.

  When the surface emitting illumination device 12 is used, the light emitting device 1 emits light. This light is transmitted through the diffusion plate 14 and emitted upward in the drawing, and illumination light with uniform brightness can be obtained within the surface of the diffusion plate 14 of the holding case 13.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist.

In the following examples , reference examples, and comparative examples, the emission spectrum and excitation spectrum were measured at room temperature using a fluorescence spectrophotometer F-4500 type (manufactured by Hitachi, Ltd.). In addition, about the fluorescent substance obtained in Reference Example 1 , a 150 W xenon lamp as an excitation light source and a fluorescence measuring apparatus (manufactured by JASCO Corporation) provided with a multi-channel CCD detector C7041 (manufactured by Hamamatsu Photonics) as a spectrum measuring apparatus The emission spectrum and excitation spectrum were measured.
The powder X-ray diffraction measurement was performed using RINT 2200PC (manufactured by Rigaku Corporation).
The carbon content of the phosphor was measured using a carbon sulfur analyzer EMIA-520 (manufactured by Horiba Seisakusho), and the oxygen content was measured for oxygen nitrogen analyzer TC430 (manufactured by LECO) for Example 3 and Reference Example 1. For Example 1 and Comparative Examples 1 and 3, the solid oxygen / nitrogen analyzer EMGA550 / EF610 (manufactured by Horiba Seisakusho) was used.

Example 1
As raw materials, 0.5 mol of CaCN ₂ , 0.5 mol of CaCO ₃ , 1 mol of Si ₃ N ₄ , 1 mol of AlN, and 0.01 mol of Eu ₂ O ₃ were weighed, and these were measured. Mix well. The obtained raw material mixture was wrapped in Mo foil, filled in a ZrB ₂ crucible, and heated at 1300 ° C. for 6 hours in a nitrogen atmosphere at atmospheric pressure using a high-frequency heating electric furnace.

  FIG. 4 shows the powder X-ray diffraction (measurement) results of the obtained phosphor powder, FIG. 5 shows the emission spectrum and excitation spectrum, and FIG. 6 shows the scanning electron microscope (SEM) photograph.

Since the pattern of FIG. 4 is almost the same as the pattern shown in WO2005 / 052087A1, the obtained powder is a single phase of CaAlSiN ₃ : Eu phosphor that is Eu-activated and emits red light. I understood.
From FIG. 5, it was found that this phosphor emits a good red light when irradiated with excitation light from the ultraviolet region to the blue region. The emission peak wavelength of this phosphor was 644 nm, and the CIE chromaticity coordinates were x = 0.63 and y = 0.36. The emission intensity when excited with light at 455 nm is a yellow phosphor ((Y, Gd) ₃ Al ₅ O ₁₂ : Ce, product number P46-Y3, manufactured by Kasei Optonix, Inc., hereinafter “YAG phosphor”. The emission intensity was 60% when the emission intensity was 100%.
From the SEM photograph of FIG. 6, it was found that the obtained phosphor was composed of particles having a particle size of about 1 μm to 5 μm.

  When the oxygen and carbon contents of this phosphor were measured, the oxygen content was 0.40% by weight and the carbon content was 0.25% by weight, indicating that both oxygen and carbon were low. . The oxygen content and carbon content are thought to depend on the firing temperature, firing time, and purity of the firing atmosphere (oxygen concentration, moisture content, etc.), but brightness is low when both the oxygen content and carbon content are low. Tend to improve.

(Example 2)
As raw materials, 1 mol of CaCN ₂ , 1 mol of CaCO ₃ , 1.66 mol of Si ₃ N ₄ and 0.01 mol of Eu ₂ O ₃ were weighed and mixed well. The obtained raw material mixture was wrapped in Mo foil, filled in a ZrB ₂ crucible, and heated at 1500 ° C. for 6 hours in a nitrogen atmosphere at atmospheric pressure using a high-frequency heating electric furnace.

FIG. 7 shows a powder X-ray diffraction (measurement) of the obtained phosphor powder, and FIG. 8 shows an emission spectrum and an excitation spectrum.
The pattern in FIG. Consistent with the pattern reported in 82-2489, it was found to be a single phase of Ca ₂ Si ₅ N ₈ : Eu.
From the emission spectrum of FIG. 8, it was found that this phosphor emits good orange to red light when irradiated with excitation light in the ultraviolet to blue range.
When this phosphor is excited with light having a wavelength of 455 nm, the emission intensity of the yellow phosphor ((Y, Gd) ₃ Al ₅ O ₁₂ : Ce, product number P46-Y3) manufactured by Kasei Optonics Co., Ltd. When it was 100%, it was 80%.

(Example 3)
As raw materials, 1 mol of CaCN ₂ , 1 mol of SrCO ₃ , 1.66 mol of Si ₃ N ₄ and 0.01 mol of Eu ₂ O ₃ were weighed and mixed well. The obtained raw material mixture was wrapped in Mo foil, filled in a ZrB ₂ crucible, and heated at 1500 ° C. for 6 hours in a nitrogen atmosphere at atmospheric pressure using a high-frequency heating electric furnace.

FIG. 9 shows the powder X-ray diffraction result of the obtained phosphor powder, FIG. 10 shows the emission spectrum and excitation spectrum, and FIG. 11 shows the SEM photograph.
The pattern of FIG. 9 takes into account the shift of diffraction angle due to the inclusion of Ca instead of Sr. JCPDS ICDD PDF No. It almost coincides with the pattern of Sr ₂ Si ₅ N ₈ reported in 85-0101 and was found to be a single phase of CaSrSi ₅ N ₈ : Eu.
From the emission spectrum of FIG. 10, it was found that this phosphor emits good orange to red light when irradiated with excitation light in the ultraviolet to blue range. The emission peak wavelength of this phosphor was 640 nm, and the CIE chromaticity coordinates were x = 0.64 and y = 0.36. FIG. 10 also shows the spectrum of a yellow phosphor ((Y, Gd) ₃ Al ₅ O ₁₂ : Ce, product number P46-Y3) manufactured by Kasei Optonics, Inc. as a comparative control.
From the SEM photograph of FIG. 11, it was found that the obtained phosphor was composed of particles having a particle size of about 1 μm to 5 μm.

  When the oxygen and carbon contents of this phosphor were measured, it was found that the oxygen content was 3.4% by weight and the carbon content was 0.09% by weight, and the carbon content was particularly low.

Example 4
The treatment was performed in the same manner as in Example 3 except that the firing temperature was 1300 ° C.
The powder X-ray diffraction (measurement) result of the obtained phosphor powder is shown in FIG. The pattern of FIG. 12 has a peak at the same diffraction angle as the phosphor powder obtained in Example 3, and was found to be a CaSrSi ₅ N ₈ : Eu phosphor.
The obtained phosphor was a little darker than the phosphor obtained in Example 3. Therefore, it can be seen that the production conditions of Example 3 are more preferable.

( Reference Example 1 )
As raw materials, 1 mol of Sr (CH ₃ COO) ₂ .0.5H ₂ O (strontium acetate), 1 mol of SrCO ₃ , 1.66 mol of Si ₃ N ₄ and 0.01 mol of Eu ₂ O ₃ Weighed in proportions and mixed them well. The obtained phosphor raw material mixture was wrapped in Mo foil, filled in a ZrB ₂ crucible, and heated at 1500 ° C. for 5 hours in a nitrogen atmosphere at atmospheric pressure using a high-frequency heating electric furnace.

FIG. 13 shows the result of powder X-ray diffraction (measurement) of the obtained phosphor powder, and FIG. 14 shows the emission spectrum when irradiated with excitation light of 455 nm. FIG. 14 also shows the emission spectrum of the aforementioned YAG phosphor.
By comparing with JCPDS standard chart 85-0101 of Figure 9 to Figure 13, the phosphor powder obtained was found to be substantially single phase of _{Sr 2 Si 5 N 8, Sr} 2 Si 5 N 8: It was found that Eu phosphor was obtained.
From FIG. 14, it was found that this phosphor emits a good red light when irradiated with excitation light from the ultraviolet region to the blue region. The emission peak wavelength of this phosphor was 627 nm, and the CIE chromaticity coordinates were x = 0.64 and y = 0.36.
The emission intensity when excited with light having a wavelength of 455 nm is 100% of the emission intensity of a yellow phosphor ((Y, Gd) ₃ Al ₅ O ₁₂ : Ce, product number P46-Y3) manufactured by Kasei Optonics. At 150%.

  When the oxygen and carbon contents of this phosphor were measured, the oxygen content was 0.45% by weight and the carbon content was 0.20% by weight, indicating that both oxygen and carbon were low. .

(Comparative Example 1)
As raw materials, 1 mol of CaCO ₃ , 0.33 mol of Si ₃ N ₄ , 1 mol of AlN, 0.01 mol of Eu ₂ O ₃ , graphite powder (manufactured by Wako Pure Chemical Industries, purity 95% or more, opening 45 μm) The sieved product) was weighed at a molar ratio of 1 and mixed well. The obtained raw material mixture was filled in a graphite crucible and heated at 1500 ° C. for 6 hours in a nitrogen atmosphere at atmospheric pressure using a high-frequency heating electric furnace.

The powder X-ray diffraction (measurement) results of the obtained phosphor powder are shown in FIG. From FIG. 15, it can be seen that the CaAlSiN ₃ : Eu phosphor described in WO2005 / 052087A1 is not generated in this comparative example. The pattern described in FIG. 15 is JCPDS-ICDD-PDF-No. It almost matches the pattern reported in 39-0747.
Further, FIG. 16 shows an emission spectrum and an excitation spectrum. Unlike the example 1, the light emission of this phosphor was orange light emission having an emission peak near 590 nm as shown in FIG. Note that the bright line near 460 nm in the excitation spectrum of FIG. 16 is derived from the xenon lamp used as the excitation light source.

  When the oxygen and carbon contents of this phosphor were measured, the oxygen content was 0.65% by weight and the carbon content was 0.21% by weight.

(Comparative Example 2)
As raw materials, 1 mol of Sr (HCOO) ₂ .2H ₂ O (strontium formate), 1 mol of SrCO ₃ , 1.66 mol of Si ₃ N ₄ and 0.01 mol of Eu ₂ O ₃ were weighed. These were mixed well. The obtained raw material mixture was wrapped in Mo foil, filled in a ZrB ₂ crucible, and heated at 1500 ° C. for 5 hours in a nitrogen atmosphere at atmospheric pressure using a high-frequency heating electric furnace.

The powder X-ray diffraction (measurement) result of the obtained phosphor powder is shown in FIG. From FIG. 17, the X-ray diffraction pattern of the product does not match the reported Sr ₂ Si ₅ N ₈ phase pattern (JCPDS ICDD PDF No. 85-0101), and the Sr ₂ Si ₅ N ₈ phase is It turned out that it did not produce.
When the obtained phosphor powder was excited at 455 nm, no light emission was observed.

(Comparative Example 3)
As raw materials, 2 mol of SrCO ₃ , 1.66 mol of Si ₃ N ₄ , 0.01 mol of Eu ₂ O ₃ , graphite powder (a product passing through a sieve with an opening of 45 μm, Wako Pure Chemical Industries, purity 95% or more) Were weighed at a 1 mole ratio and mixed well. The obtained raw material mixture was wrapped in Mo foil, filled in a ZrB ₂ crucible, and heated at 1500 ° C. for 6 hours in a nitrogen atmosphere at atmospheric pressure using a high-frequency heating electric furnace.
The powder X-ray diffraction (measurement) result of the obtained powder is shown in FIG. FIG. 18 shows that Sr ₂ Si ₅ N ₈ is formed almost in a single phase, and that Sr ₂ Si ₅ N ₈ : Eu phosphor is obtained.

However, when the oxygen and carbon contents of this phosphor were measured, the oxygen content was 1.9% by weight and the carbon content was 0.3% by weight, which was obtained in Reference Example 1 . It was found that both oxygen and carbon were contained more than phosphors.
Note that the emission intensity of the obtained phosphor powder was lower than that of the phosphor powder obtained in Reference Example 1 .

From the above results, it can be seen that according to the method for producing a phosphor of the present invention, a bright phosphor having a low carbon content can be produced. Further, it becomes possible to manufacture a CaAlSiN ₃ : Eu phosphor that cannot be manufactured by the conventional CRN method.

It is typical sectional drawing which shows the light-emitting device which concerns on one Embodiment of this invention. It is a typical perspective view which shows other embodiment of the light-emitting device of this invention. It is typical sectional drawing which shows an example of the surface emitting illumination apparatus using the light-emitting device of this invention. 3 is a chart showing powder X-ray diffraction (measurement) results of the phosphor powder obtained in Example 1. FIG. 2 is a chart showing an emission spectrum and an excitation spectrum of the phosphor powder obtained in Example 1. FIG. 2 is a scanning electron microscope (SEM) photograph of the phosphor powder obtained in Example 1. FIG. 4 is a chart showing powder X-ray diffraction (measurement) results of the phosphor powder obtained in Example 2. FIG. 6 is a chart showing an emission spectrum and an excitation spectrum of the phosphor powder obtained in Example 2. 6 is a chart showing a powder X-ray diffraction (measurement) result of the phosphor powder obtained in Example 3. FIG. 4 is a chart showing an emission spectrum and an excitation spectrum of the phosphor powder obtained in Example 3. 4 is a scanning electron microscope (SEM) photograph of the phosphor powder obtained in Example 3. FIG. 6 is a chart showing a powder X-ray diffraction (measurement) result of the phosphor powder obtained in Example 4. 6 is a chart showing a powder X-ray diffraction (measurement) result of the phosphor powder obtained in Reference Example 1 . 6 is a chart showing an emission spectrum of the phosphor powder obtained in Reference Example 1 . 6 is a chart showing a powder X-ray diffraction (measurement) result of the phosphor powder obtained in Comparative Example 1. 6 is a chart showing an emission spectrum and an excitation spectrum of the phosphor powder obtained in Comparative Example 1. 6 is a chart showing powder X-ray diffraction (measurement) results of the phosphor powder obtained in Comparative Example 2. 6 is a chart showing a powder X-ray diffraction (measurement) result of the phosphor powder obtained in Comparative Example 3.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light-emitting device 2 Frame 2A Recessed part of frame 3 Blue LED (first light emitter)
4 Phosphor-containing part (second light emitter)
5 Silver paste 6 Wire 7 Mold part 8 Light-emitting device 9 Substrate 10 Surface-emitting GaN-based LD (first light emitter)
DESCRIPTION OF SYMBOLS 11 2nd light-emitting body 12 Surface emitting illuminating device 13 Holding case 14 Diffusion plate 21 1st light-emitting body (LED)
22 Phosphor-containing part 23 Frame 24 Wire 25, 26 Electrode

Claims (13)

CaAlSiN _Three , (Mg, Ca, Sr, Ba) AlSiN _Three , Sr ₂ Si _Five N ₈ , (Mg, Ca, Sr, Ba) ₂ Si _Five N ₈ A method for producing a phosphor based on any one of the nitrides of
Mixing a raw material containing a carbon-containing compound having a reducing action and having no O element;
A step of firing the obtained raw material mixture,
The carbon-containing compound having no O element is cyanamide (H ₂ N-CN) metal salt or dicyanamide metal salt. A method for producing a phosphor using a nitride as a base material. The nitride is CaAlSiN _Three , (Ca, Sr) AlSiN _Three , Sr ₂ Si _Five N ₈ , (Ca, Sr) Si _Five N ₈ The method for producing a phosphor based on a nitride according to claim 1, wherein the phosphor is based on any one of the above. 3. The method for producing a phosphor based on a nitride according to claim 1, wherein the Group 2 element of the periodic table is Ca. 4. A phosphor based on a nitride or oxynitride produced by the method according to any one of claims 1 to 3 . The phosphor containing a nitride or oxynitride as a base according to claim 4 , wherein the carbon content is 0.5% by weight or less. 6. The phosphor based on a nitride according to claim 5 , wherein the oxygen content is 0.5% by weight or less. The phosphor containing the nitride or oxynitride according to any one of claims 4 to 6 , wherein the phosphor contains Si element. 8. The phosphor based on a nitride or oxynitride according to any one of claims 4 to 7 , comprising at least one element of Group 2 elements of the periodic table. A phosphor-containing composition comprising the phosphor according to any one of claims 4 to 8 and a liquid medium. A first light emitter, and a second light emitter that emits visible light by irradiation of light from the first light emitter,
9. A light emitting device, wherein the second light emitter contains at least one of the phosphors according to any one of claims 4 to 8 as a first phosphor. The light emission according to claim 10 , wherein the second phosphor includes at least one phosphor having a light emission peak wavelength different from that of the first phosphor as the second phosphor. apparatus. The image display apparatus comprising: a light-emitting device according as the light source in claim 10 or 11. An illumination device comprising the light-emitting device according to claim 10 or 11 as a light source.

Images