JP2007056123A - Method for producing phosphor for electroluminescence and phosphor for electroluminescence - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a phosphor for EL (electroluminescence) suppressing a leak phenomenon and continuously emitting the El of light in a short wavelength region at high intensity and to provide the phosphor for the EL emitting the EL of visible light at the short wavelength or ultraviolet light by efficiently generating electric field concentration even when the phosphor of a material which originally does not emit the EL with high efficiency is used. <P>SOLUTION: Metal powder consisting essentially of at least one kind of metal selected from the group consisting of Zn, Be, Mg, Ca, Sr and Ba and a material composed of carbon are mechanically ironed and alloyed when the phosphor for the EL is prepared. Thereby, the material composed of the carbon to be an electroconductive layer is uniformly dispersed in the phosphor. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a phosphor that emits short-wavelength visible light and ultraviolet light with high luminescence intensity and electroluminescence (hereinafter abbreviated as “EL”).

Due to recent environmental problems, a function of separating, decomposing or sterilizing harmful substances, bacteria, viruses and the like is strongly demanded. Photocatalytic materials are attracting attention as a means for performing such decomposition and sterilization. A typical photocatalyst is TiO ₂ , which generally exhibits a photocatalytic function when irradiated with ultraviolet rays having a wavelength of 400 nm or less.

  Devices that emit light of such a wavelength include mercury lamps and light emitting diodes, but they are point or line light sources and are not suitable for uniformly exciting a large area photocatalyst. There is an inorganic EL device as a device that uniformly emits light over a large area. In this method, phosphor powder having a function of emitting light is dispersed in a dielectric resin, and light is emitted mainly by applying an alternating electric field.

Examples of phosphors that emit light with high efficiency include ZnS phosphors. For example, Patent Document 1 discloses a phosphor in which the luminous efficiency is increased by forming CuS by adding Cu and Cl to a ZnS matrix. Patent Document 2 discloses a phosphor whose luminous efficiency is increased by a mixed crystal of a ZnS-based phosphor and a group 2A element such as MgS.
In general, among the ZnS phosphors, those that emit light of a short wavelength are activated by Ag, but the emission wavelength is blue of 450 nm and emits only light in the visible light region. In this light emission mechanism, Ag of the activator added in ZnS forms an acceptor level, and Cl, Al, etc. added as a coactivator form a donor level, and this donor level and acceptor By recombination of electrons and holes between levels, DA-type (also called Green-Cu type, hereinafter referred to as G-Cu type) blue light emission having a wavelength of about 450 nm occurs. This G-Cu type light emission increases the band gap of the phosphor base material by a mixed crystal of the phosphor base material with a compound having a larger band gap than ZnS and ZnS, for example, a group 2A element sulfide such as MgS or CaS. It is considered that the wavelength can be shortened.

  However, such a phosphor doped with Ag could not emit EL. The reason for this will be described below. The most common ZnS: Cu, Cl phosphor as an EL phosphor has a large number of twins (stacking faults) formed inside the phosphor, and a highly conductive Cu-S system along the twin interface. The compound exists in a needle shape. When an electric field is applied, electric field concentration occurs at the tip of the acicular conductive phase, and the phosphor matrix, ZnS, is excited, and this energy moves to various levels in the phosphor to emit EL.

The general manufacturing method of this phosphor is as follows. A mixed powder obtained by adding CuSO ₄ or KCl to ZnS as a raw material powder is fired at 1000 to 1100 ° C. for several hours in an inert atmosphere, and then cooled to room temperature. A number of twins called growth twins are formed at the grain growth stage of ZnS generated during firing. Furthermore, in the cooling step to room temperature after firing, a phase transition from hexagonal to cubic occurs in ZnS, and a number of twins called transition twins are formed. At this time, of the added Cu component, Cu exceeding the solid solubility limit of ZnS precipitates as a needle-like Cu-S compound at the twin interface. The Cu—S compound is generally said to be Cu ₂ S. When Ag is doped instead of Cu, it is Ag ₂ S that precipitates at the twin interface, and the electric field concentration effect is not exhibited because of low conductivity.

On the other hand, it has been reported that by attaching conductive particles to the phosphor surface, electric field concentration is generated in the vicinity of the conductive particles when an electric field is applied, thereby causing EL emission (for example, Patent Document 3). However, in such a phosphor, since the resistance of the phosphor surface decreases due to the adhesion of conductive particles, a leak phenomenon occurs in which the electric field escapes along the phosphor surface when an electric field is applied. Only EL phosphors with extremely short emission lifetimes were obtained.
Japanese Patent Laid-Open No. 5-152073 JP 2002-231151 A Japanese Patent Publication No. 7-47732

Therefore, an object of the present invention is to provide a method for producing an EL phosphor capable of suppressing such a leak phenomenon and continuously emitting EL in a short wavelength region with high intensity.
Furthermore, an object of the present invention is to provide an EL phosphor capable of EL emission of short-wavelength visible light and ultraviolet light by efficiently generating electrolysis concentration even with a material-based phosphor that is originally highly efficient and does not emit EL light. And

  In light of the above-mentioned object, the present inventors have conducted intensive research. As a result, by uniformly dispersing a conductive phase containing a highly conductive carbon component inside the phosphor, a fluorescent material having high emission intensity as a phosphor for short wavelength EL. It has been found that it becomes a body, and has led to the present invention.

That is, the present invention is characterized by having the following configuration.
(1) Mechanical alloying (hereinafter referred to as “MA”) is made of a metal powder composed mainly of at least one metal selected from the group consisting of Zn, Be, Mg, Ca, Sr and Ba and carbon. Any one of the above, a step of alloying the alloy, a step of sulfiding the alloy to form a composite containing sulfide as a main component, a step of pulverizing and heat-treating the composite to form a phosphor, and And a step of adding an activator and / or a coactivator in the step, and a method for producing an EL phosphor.
(2) The phosphor for EL as described in (1) above, wherein in the step of sulfiding the alloy to form a composite containing sulfide as a main component, sulfur powder is added to the alloy and MA is performed. The manufacturing method.
(3) Sulfurization is carried out by MA with a material composed of at least one metal selected from the group consisting of Zn, Be, Mg, Ca, Sr and Ba, sulfur powder, and carbon. From the step of making a composite with an object as a main component, the step of pulverizing and heat-treating the composite to make a phosphor, and the step of adding an activator and / or a coactivator in any of the above steps, The manufacturing method of the fluorescent substance for EL which becomes.
In the present invention, when a composite containing sulfide as a main component is produced, sulfur powder is used to sulfidize with MA, so that the problem of exhaust gas treatment that occurs in the case of sulfidation by reacting with H ₂ S gas is eliminated. .

(4) The method for producing a phosphor for EL according to any one of (1) to (3), wherein the metal powder contains Zn as a main component.
(5) The method for producing an EL phosphor according to (4), wherein the metal powder contains a mixture of Zn and at least one of Be, Mg, Ca, Sr, or Ba as a main component.

(6) The method for producing an EL phosphor according to any one of (1) to (5), wherein the activator is at least one of Ag, Cu, or Au.
(7) The process for producing an EL phosphor as described in (6) above, wherein the activator is Ag.
(8) The manufacturing method of the phosphor for EL as described in said (1)-(7) which adds the said activator with a metal powder.

(9) The EL fluorescence according to any one of (1) to (8), wherein the coactivator is at least one of F, Cl, Br, I, B, Al, Ga, In, or Tl. Body making method.
(10) The process for producing a phosphor for EL according to any one of (1) to (9), wherein the coactivator is added as a metal powder.

(11) The method for producing a phosphor for EL according to any one of (1) to (10), wherein the material composed of carbon is at least one selected from carbon nanotubes, carbon nanohorns, fullerenes, and graphite. .
(12) The shape of the material composed of carbon is needle-like, and the aspect ratio at a diameter of 100 nm or less is 100 or more, (1) to (11) above Manufacturing method of phosphor for EL.
(13) The method for producing an EL phosphor according to any one of (1) to (12), wherein the material composed of carbon is 0.005 to 1 vol% of the sulfide.

(14) The phosphor has the general formula Zn _(1-x) A _x S: Ag, D (where A is at least one 2A selected from the group consisting of Be, Mg, Ca, Sr and Ba) Group element D is a coactivator, and is a composition represented by at least one selected from the group consisting of Group 3B and Group 7B elements, 0 <x <1) (1) to (13 ). The manufacturing method of the fluorescent substance for EL as described in any one of.
(15) A phosphor for EL produced by the method according to any one of (1) to (14).

  The present invention relates to a method for producing a phosphor in which a conductive phase containing a carbon component is uniformly dispersed inside a sulfide phosphor. For example, a metal powder and a carbon component are used as starting materials, and this is alloyed and pulverized by a technique such as MA to obtain a metal powder in which the carbon component is dispersed with extremely high uniformity. This is doped with an element serving as a predetermined emission center, and then sulfided to obtain a sulfide phosphor in which the carbon component is dispersed with high dispersibility, and a high electric field concentration occurs due to EL, so that a high EL emission intensity is obtained. It is done.

  Further, in the present invention, phosphors based on sulfides are doped with Ag, which is originally highly efficient and does not emit EL light, as an activator. For example, carbon nanotubes or the like are incorporated into ZnS-based phosphors as conductive carbon components. As a phosphor that emits high intensity light by uniformly dispersing as a conductive phase.

  The phosphor can be produced, for example, by mixing a carbon nanotube powder or the like and a ZnS powder that is a raw material of the phosphor using MA or the like, and then producing the phosphor by a normal powder firing method. Since the agglomeration occurs at the time of mixing, and the aggregation is not crushed even after firing, it is difficult to effectively function the high aspect ratio of the carbon nanotube alone, so that a high electric field concentration effect does not appear, so the EL emission intensity is low .

In contrast, the present invention is characterized in that metal powder is used as a starting material instead of phosphor powder. Hereinafter, a carbon nanotube will be described as an example of a material composed of carbon.
For example, when metal zinc powder and carbon nanotubes are blended in a predetermined composition and subjected to a mixing process such as MA, the metal is highly ductile and malleable, so that the metal structure is repeatedly stretched and folded in the MA. At this time, the aggregates of the carbon nanotubes are crushed and finally become a powder dispersed with high dispersibility in metallic zinc. The MA treatment may be performed by a general ball mill (hereinafter referred to as “BM”). If a planetary BM having a large grinding energy is used, grinding at high acceleration becomes possible, and dispersibility is further enhanced. The larger the pulverization acceleration during MA and the longer the time, the better the dispersion state of the carbon nanotubes. However, even if the carbon nanotubes are aggregated, the carbon nanotubes are needle-shaped, so that electrolytic concentration easily occurs, and EL emission occurs when the tip of the aggregate is in contact with the phosphor.
For example, a mixture of Zn and carbon nanotube powder and a ball used for BM crushing are filled in a BM pot, and the pot is revolved and pulverized. The rotational acceleration of the pot is preferably 10G or more. If it is less than this, the pulverization energy is not significantly different from that in the case of using ordinary BM, and it takes time to pulverize and the efficiency is poor. In a normal planetary BM, the energy can be increased to about 150 G acceleration. At this time, it is preferable that impurities such as Fe, Cr, Ni, Co and the like from the partition walls of the balls and pots can be prevented. These elements become phosphor luminescence killer.

After collecting this, for example, an Ag element for doping and KCl as a fluxing agent are added, and then fired in a reducing gas containing H ₂ S gas to obtain a ZnS: Ag, Cl phosphor. The high dispersibility of the carbon nanotubes in the metallic zinc is maintained even after the conversion to ZnS, so that the powder has a structure in which the carbon nanotubes with high conductivity are uniformly dispersed inside the phosphor.

  As the metal raw material, a metal powder containing at least one metal selected from the group consisting of Zn, Be, Mg, Ca, Sr and Ba as a main component is used. It is preferable to select a single substance or a plurality of kinds and use them in various compositions to finally produce a phosphor, because the band gap of the phosphor matrix can be changed. Among these, in view of moisture resistance, it is preferable to use Zn as a main component. Furthermore, since sulfides of Group 2A metals such as Be, Mg, Ca, Sr and Ba are not high in moisture resistance, it is preferable to use a mixed powder of Zn and these metals as a starting material, and finally mix ZnMgS, ZnCaS, etc. It is particularly preferable to use a crystal matrix.

When the above metal powder and carbon nanotubes are MA and sulfurized to form a sulfide, it is often in the form of a lump, so it is better to grind. In either step, an activator and a coactivator are added and heat treated to obtain a phosphor. The heat treatment is performed in order to remove the distortion generated in the phosphor by MA. As a method therefor, there are methods such as laser annealing, infrared lamp heating, plasma heating, etc. in addition to firing in a normal furnace. . The activator is preferably Ag, but Cu or Au may also be used. When Cu or Au is added, they are deposited in the phosphor as highly conductive Cu ₂ S and Au after heat treatment, so EL emission occurs even if carbon nanotubes are not present. The emission intensity is increased. The addition of the activator is not limited as long as it is performed with sulfides or chlorides such as AgCl and Ag ₂ SO ₄ . As the coactivator, general-purpose materials such as F, Cl, Br, I, B, Al, Ga, In, or Tl are used. These are often added in the form of KCl or NaCl, but are not limited thereto. These activators and coactivators may be added before the MA treatment. Moreover, you may add an activator with a metal powder. For example, a Zn—Mg—Ag alloy may be MA. It is also possible to add the coactivator as a metal powder. For example, if a Zn—Mg—Ag—Al alloy is used, it is not necessary to add an activator or a coactivator after the MA treatment.

In the present invention, the phosphor has the general formula Zn _(1-x) AxS: Ag, D (wherein A is at least one 2A group element selected from the group consisting of Be, Mg, Ca, Sr and Ba) , D is composed of a composition represented by at least one selected from Group 3B or Group 7B elements and a mixing ratio x of 0 ≦ x <1), and is also applicable to a phosphor having a Blue-Cu type light emitting function. it can. When the phosphor is mainly composed of such a composition, it is particularly preferable from the viewpoint of light emission at a short wavelength. In this phosphor, the base material of the phosphor is a mixed crystal matrix in which 2A group sulfides such as MgS and CaS having a large band gap are mixed based on ZnS, Ag as an acceptor, and 3B such as Cl and Al as a donor. Is a phosphor having a Blue-Cu type light emitting function, and the peak wavelength of the EL spectrum can be in the region of 400 nm or less. Such a phosphor having a Blue-Cu type light emission can be prepared by containing Ag as an activator (acceptor) at a molar concentration equal to or higher than the molar concentration of the coactivator (donor).

  In a phosphor emitting G-Cu type light, for example, ZnS: Ag, Cl, Ag substitutes the Zn position of the ZnS crystal lattice, and Cl substitutes the S position. On the other hand, in the present invention, by adding Ag at a molar concentration higher than the molar concentration of the coactivator to the ZnS-based phosphor, Ag that is not newly charge-compensated in addition to Ag replacing the Zn position. Is introduced between the crystal lattices of ZnS. Furthermore, the crystal lattice is expanded by making the phosphor base material a mixed crystal of ZnS and a group 2A sulfide selected from at least one of BeS, MgS, CaS, SrS and BaS, and more Ag is latticed. Made it easy to intrude in between. When such a mixed crystal phosphor is used, the peak wavelength of the EL emission spectrum can be reduced to 388 nm or less.

In the present invention, the general formula of the phosphor doped with Cu is Zn _(1-x) AxS: Cu, D (wherein A is at least one selected from the group of Be, Mg, Ca, Sr and Ba). The group 2A element, D, is at least one selected from the group 3B or group 7B elements, 0 ≦ x <1), and can also be applied to a phosphor having a Blue-Cu type light emitting function. In the case of doping with Cu, a Cu—S compound is deposited, so that it is not particularly necessary for the ZnS phosphor. However, this method is effective for phosphors whose crystal structure is hexagonal over the entire temperature range, such as ZnMgS and ZnCaS. This is because these mixed crystal phosphors are unlikely to form growth twins and do not generate transition twins, so that they emit EL only at low brightness in the same normal firing as ZnS. By using the present invention, EL light can be emitted with high luminance.

The specific resistance of the material composed of carbon is preferably 10 ⁻¹ Ωcm or less. Below this, the electric field concentration effect decreases. Carbon nanotubes, carbon nanohorns, fullerenes, graphite, and the like are candidates for materials composed of carbon. In particular, carbon nanotubes and carbon nanohorns are preferable because they have a needle-like shape, a small diameter, and a large aspect ratio, so that an electric field is easily concentrated. Preferably, the diameter is 100 nm or less and the aspect ratio is 100 or more.

  The content of the material to be the conductive phase is preferably adjusted to 0.005 to 1 vol% of the sulfide after sulfidation. If it exceeds this, the conductive phases may contact and connect with each other, and an electric field may not be applied to the phosphor. If it is less than this, the number of locations where the electric field concentrates decreases, and the EL emission intensity may decrease.

By using the present invention, it is possible to produce an EL phosphor capable of suppressing light leakage and emitting light in a short wavelength region with high intensity and continuous EL emission.
Furthermore, the product of the present invention has an effect that a phosphor doped with Ag capable of emitting light at a short wavelength can emit EL. In particular, by making a phosphor base material having a large band gap such as MgS into ZnS, it is possible to easily develop short wavelength light emission with a peak light emission wavelength of 400 nm or less. An inorganic EL device using these phosphors is promising as an ultraviolet surface light source that can efficiently excite a photocatalyst.

Example 1
(I) Raw Material (1) Carbon Carbon nanotubes (hereinafter referred to as “CNT”) or carbon nanohorns (hereinafter referred to as “CNH”) having various diameters, aspect ratios, and specific resistances shown in Table 1 are prepared. did.
(2) Metal powder Zn, Mg, Sr, Ca, and Be powders having a purity of 99.999% and an average particle diameter of 30 μm were prepared.
(3) Activator / Co-activator Activator: Ag ₂ S powder with an average particle size of 1 μm Co-activator: Various powders with an average particle size of 20 μm

(II) Mixing Carbon and metal powder were blended so as to have a predetermined composition. A ball made of Si ₃ N ₄ having a diameter of 3 mm was added thereto, and pulverized and mixed with planetary BM using a Si ₃ N ₄ pot at an acceleration of 75 G for 60 minutes.
(III) Heat treatment An activator and a coactivator are added to the recovered raw material mixture, put into a quartz crucible with a lid of 20 × 200 × 20 mm (height), and 10% of 1 atm using a tubular furnace. After firing at 1050 ° C. for 6 hours in H ₂ S—H ₂ gas, it was naturally cooled to room temperature in the furnace. Thereafter, the phosphor was pulverized with BM until the average particle size became 15 μm.

(Evaluation method of emission wavelength)
A 50 × 50 × 1 mm (thickness) quartz glass substrate was subjected to a concave processing of 40 × 40 × 50 μm (depth), and then Al was evaporated to a thickness of 0.1 μm to form a back electrode. The phosphor was ultrasonically mixed with castor oil at a volume fraction of 35 vol% to form a slurry, which was poured into the recess. Finally, a 50 × 50 × 1 mm quartz glass substrate coated with a transparent conductive film (surface electrode) having a thickness of 0.1 μm was covered to obtain an EL device.
Lead wires were attached to both electrodes, and an AC voltage having a voltage of 500 V and a frequency of 2500 Hz was applied. The emission spectrum was measured with the same sensitivity using a photonic analyzer. The emission intensity of some samples was compared. The relative intensities of the peak wavelengths of the obtained emission spectra were compared.
The results are shown in Table 1.

As is clear from Table 1, phosphors that did not use CNT did not emit EL (phosphors No. 1, 3).
In the ZnS-MgS system, light was emitted at a short wavelength by increasing the activator amount more than the coactivator amount. It is considered that Blue-Cu type light emission occurred (comparison of No. 4 and 5).
The EL emission intensity increased as the specific resistance of CNTs decreased (No. 6-8).
Even when CNH was used, EL was emitted (No. 9).
The smaller the CNT diameter and the larger the aspect ratio, the higher the EL emission intensity (No. 10 and 11).
Even when Sr, Ca, Ba was used in place of Mg, short wavelength EL emission was obtained (No. 12-14).

Example 2
(I) Raw material (1) Carbon The same material as in Example 1 was used.
(2) Metal powder The same powder as in Example 1 was used.
(3) Activator / Co-activator Activator: Ag, Cu or Au powder with an average particle size of 1 μm Co-activator: Various powders with an average particle size of 20 μm

(II) Mixing Carbon and metal powder, an activator, and a coactivator were blended so as to have a predetermined composition. A ball made of Si ₃ N ₄ having a diameter of 3 mm was added thereto, and pulverized and mixed for 60 minutes at an acceleration of 75 G using a planetary BM using a pot made of Si ₃ N ₄ .
(III) Heat treatment The recovered raw material mixture is put into a quartz crucible with a lid of 20 × 200 × 20 mm (height), and using a tubular furnace at 1050 ° C. in 10% H ₂ S—H ₂ gas at 1 atm. After baking for 6 hours, it naturally cooled to room temperature in the furnace. Thereafter, the phosphor was pulverized with BM until the average particle size became 15 μm.

(Evaluation method of emission wavelength)
Same as Example 1.
As a comparison, a sample was prepared by adding CNT to a commercially available ZnS: Ag, Cl phosphor powder, performing the same planetary BM treatment, and then performing the same heat treatment.
The results are shown in Table 2.

As can be seen from Table 2, EL was emitted even when metal powder was used as the activator and coactivator.
The EL emission intensity was increased by setting the amount of CNT to an appropriate value. When ZnS was used as the starting material, the EL emission intensity was extremely small. This is probably because CNT is not dispersed inside the phosphor (compare No. 15-19, 22).
Even when Cu or Au powder was used, EL was emitted.
When Cu was used, the emission intensity increased with the presence of CNT (comparison between No. 19 and 20).

Example 3
(I) Raw material (1) Carbon Carbon species: CNT
Carbon species diameter: 5nm
Carbon species length: 550 nm
Aspect ratio: 110
Specific resistance: 0.02 Ωcm
Carbon species concentration: 0.01 vol%
(2) Metal powder The same powder as in Example 1 was used.
(3) Activator / Co-activator Activator: Ag powder with an average particle size of 1 μm Co-activator: Al powder with an average particle size of 20 μm (4) Sulfur: Sulfur powder with a purity of 99.999% (average particle A diameter of 5 μm) was used.

(II) Mixing Carbon and metal powder, activator, coactivator, and sulfur powder were blended so as to have a predetermined composition. A ball made of Si ₃ N ₄ having a diameter of 3 mm was added thereto, and pulverized and mixed for 60 minutes at an acceleration of 5 to 75 G using a planetary BM using a pot made of Si ₃ N ₄ .
Carbon, metal powder, activator, and coactivator were first pulverized and mixed for 60 minutes, and then a sulfur powder was added and pulverized and mixed again for 60 minutes.
(III) Heat treatment The recovered raw material mixture is put into a quartz crucible with a lid of 20 x 200 x 20 mm (height), heat treated at 1000 ° C in 1 atmosphere of argon gas for 2 hours, and then naturally brought to room temperature in the furnace. Cooled down.
Each phase in the phosphor after the heat treatment was as follows.
First component ZnS
Second component MgS
Second component amount (mol%): 30

(Evaluation method of emission wavelength)
Same as Example 1.
The results are shown in Table 3.

As can be seen from Table 3, EL light was emitted even when a mixed powder of metal, CNT, sulfur, activator and coactivator was used.
The EL emission intensity increased as the pulverization acceleration of the planetary BM was increased. This is probably because the higher the pulverization acceleration, the more uniformly the CNTs are dispersed in the phosphor (compare No. 23 to 26).
Without heat treatment, the emission intensity was significantly reduced. This is presumably because the distortion introduced into the phosphor matrix by pulverization is not relaxed, and the crystallinity is low (No. 27).
A sample in which the mixed powder excluding the sulfur powder was pulverized first, and then the sulfur powder was added and pulverized again had the highest emission intensity. It is thought that the pulverization of the metal and the CNTs first causes the CNTs to have higher dispersibility (No. 28).

Claims (15)

Mechanically alloying and alloying a metal powder composed mainly of at least one metal selected from the group consisting of Zn, Be, Mg, Ca, Sr and Ba, and carbon, Activating and / or coactivator in a step of sulfiding to form a composite containing sulfide as a main component, a step of pulverizing and heat-treating the composite to form a phosphor, and any of the above steps A process for producing a phosphor for electroluminescence (hereinafter abbreviated as “EL”) comprising the step of adding. 2. The process for producing an EL phosphor according to claim 1, wherein in the step of sulfiding the alloy into a composite mainly composed of sulfide, sulfur alloy is added to the alloy and mechanically alloyed. . Sulfide by mechanically alloying a metal powder composed mainly of at least one metal selected from the group consisting of Zn, Be, Mg, Ca, Sr and Ba, sulfur powder, and carbon. A step of making the composite as a main component, a step of pulverizing and heat-treating the composite to make a phosphor, a step of adding an activator and / or a coactivator in any of the above steps, The manufacturing method of the fluorescent substance for EL which consists of. The method for producing a phosphor for EL according to any one of claims 1 to 3, wherein the metal powder contains Zn as a main component. The method for producing a phosphor for EL according to claim 4, wherein the metal powder is mainly composed of a mixture of Zn and at least one of Be, Mg, Ca, Sr or Ba. The method for producing a phosphor for EL according to any one of claims 1 to 5, wherein the activator is at least one of Ag, Cu, or Au. The method for producing a phosphor for EL according to claim 6, wherein the activator is Ag. The manufacturing method of the fluorescent substance for EL as described in any one of Claims 1-7 which adds the said activator with a metal powder. The method for producing a phosphor for EL according to any one of claims 1 to 8, wherein the coactivator is at least one of F, Cl, Br, I, B, Al, Ga, In, or Tl. The method for producing a phosphor for EL according to any one of claims 1 to 9, wherein the coactivator is added as a metal powder. The method for producing a phosphor for EL according to any one of claims 1 to 10, wherein the material composed of carbon is at least one selected from carbon nanotubes, carbon nanohorns, fullerenes, and graphite. The method for producing a phosphor for EL according to any one of claims 1 to 11, wherein the material composed of carbon has a needle shape and an aspect ratio of 100 or less in diameter of 100 nm or less. The method for producing a phosphor for EL according to any one of claims 1 to 12, wherein the material composed of carbon is 0.005 to 1 vol% of the sulfide. The phosphor has the general formula Zn _(1-x) A _x S: Ag, D (where A is at least one 2A group element selected from the group consisting of Be, Mg, Ca, Sr and Ba, D is a coactivator and is a composition represented by at least one selected from the group consisting of Group 3B and Group 7B elements, 0 <x <1). A process for producing a phosphor for EL as described in 1. The phosphor for EL produced by the method as described in any one of Claims 1-14.