TW201540812A - Complex fluoride phosphor and method for producing same - Google Patents

Abstract

Provided is a method for producing a Mn-activated complex fluoride red phosphor represented by formula (I), A2MF6: Mn (I) (In the formula, M is one type or more of a tetravalent element selected from Si, Ti, Zr, Hf, Ge, and Sn, and A is one type or more of an alkali metal selected from Li, Na, K, Rb, and Cs, and includes at least Na and/or K.), the method comprising sequentially dissolving individual source components in water and from the obtained aqueous solution eventually precipitating the red phosphor in the solution. According to the present invention, since the sources can be added one by one to a reactor, the complex fluoride phosphor can be produced rationally and at high production rates.

Description

Complex fluoride phosphor and manufacturing method thereof

The present invention relates to a formula A ₂ MF ₆ : Mn which can be used as a red fluoride phosphor for blue LEDs (wherein M is one or two selected from Si, Ti, Zr, Hf, Ge and Sn) In the above tetravalent element, A is an alkali metal selected from Li, Na, K, Rb, and Cs and containing at least one or two or more kinds of Na and/or K. The Mn-activated complex fluoride red phosphor (polyfluoride phosphor) represented by the method and a method for producing the same.

In order to enhance the color reproducibility of a white LED (Light Emitting Diode) or to use a white LED as a backlight of a liquid crystal display, it is necessary to emit red light by exciting the light of the LED which is relatively close to ultraviolet to blue. The phosphor is being studied. In the above-mentioned Japanese Patent Publication No. 2009-528429 (Patent Document 1), it is described in the formula of A ₂ MF ₆ (A is Na, K, Rb, etc., M is Si, Ge, Ti, etc.). It is useful to add Mn (polyfluoride phosphor) to fluoride.

In the method for producing a phosphor described above, Patent Document 1 discloses a method in which a hydrofluoric acid solution in which all of the elements are dissolved or dispersed is evaporated and concentrated. As a separate method, in the US patent In the specification of No. 3,576,756 (Patent Document 2), a method in which a hydrofluoric acid solution in which each element is dissolved is mixed and then acetone is added to a water-soluble organic solvent to lower the solubility and precipitate. Further, Japanese Patent No. 4582259 (Patent Document 3) and JP-A-2012-224536 (Patent Document 4) disclose that the element M and the element A in the above formula are respectively dissolved in respective contents. A solution of hydrogen fluoride is mixed again in a method in which Mn has been added to precipitate a phosphor.

The manufacturing steps of the above-mentioned known Mn-added A ₂ MF ₆ (A is Na, K, Rb, etc., M is Si, Ge, Ti, etc.) complex fluoride phosphors can be applied to a small amount of synthesis in the laboratory. However, large-scale implementation of industrial sites needs to be explored. In the case of the known method, in the case of a method of mixing a water-based solution suitable for mass production (Japanese Patent No. 4582259, JP-A-2012-224536), the manufacturing steps in which the actual industrial manufacturing apparatus is taken into consideration are still in the process. Review.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a method for producing a complex fluoride phosphor suitable for industrialization and mass production, and a perfluorofluoride phosphor produced by the production method.

In order to achieve the above object, the present inventors focused on the flow of substances in the production steps of the complex fluoride phosphor, and strived to investigate the results of the steps which can be carried out reasonably and efficiently, and found that the main reaction vessel provided with the stirring device was added. Water, in which the raw material for the complex fluoride phosphor represented by the production formula A ₂ MF ₆ : Mn (however, A and M are the same as above) is sequentially dissolved, especially after the hydrogen fluoride is introduced into the water, and the input contains M. a compound, a compound containing A, a compound containing Mn or a compound containing A and Mn, stirred, dissolved, and further added with a fluoride of A or a hydrogen fluoride solution dissolved therein, and the above-mentioned double fluoride is added to the added region. The method of depositing fine particles of a phosphor has high productivity and is highly rational, and the present invention has been completed.

Accordingly, the present invention provides a method for producing a polyfluorinated phosphor described below and the phosphor.

[1] A method for producing a complex fluoride phosphor, which is characterized by the following formula (I) A ₂ MF ₆ : Mn (I) (wherein M is composed of Si, Ti, Zr, Hf, Ge, and Sn) One or two or more kinds of tetravalent elements selected, and A is an alkali metal selected from Li, Na, K, Rb, and Cs and containing at least one or two or more kinds of Na and/or K. In the production of the Mn-activated complex fluoride red phosphor shown, various components as raw materials are sequentially dissolved in water, and the red phosphor is finally precipitated in the solution from the obtained aqueous solution.

[2] The method for producing a complex fluoride phosphor according to [1], wherein water is prepared in a container, hydrogen fluoride is introduced therein, and then a compound containing M (but M is as described above) is introduced, followed by stirring. Dissolving, and then injecting a compound containing A (but A with the above) and a compound containing Mn or a compound containing A (but A with the above) and Mn, stirring and dissolving to prepare a matrix solution, and finally stirring the substrate solution After adding an additive comprising a fluoride of A (but A with the above) or a hydrofluoric acid solution in which the fluoride is dissolved, A ₂ MF ₆ :Mn is added to the matrix solution (however, A and M are the same) The above) is precipitated.

[3] The method for producing a complex fluoride phosphor according to [2], wherein the substrate solution is stirred by a stirrer at a number of revolutions in the range of 0.5 to 100 times/second when the additive is added.

[4] The method for producing a complex fluoride phosphor according to [2] or [3], wherein the additive is applied in a predetermined amount of 1/500 to 1/10 of the total amount of the additive for each second. Add it.

[5] The method for producing a complex fluoride phosphor according to any one of [1] to [4], which is used in a main reaction vessel having a stirring mechanism, and is provided with a valve fitting for supplying various solutions and A re-fluoride phosphor is produced by a pump, a powder supply device, and a device for discharging a valve containing a slurry of the produced complex fluoride phosphor.

[6] A red complex fluoride phosphor for a blue LED represented by the formula A ₂ MF ₆ : Mn (however, A and M are the same as above), which is characterized by any one of [1] to [5] The production method described in the article was obtained, and the internal quantum efficiency was 0.8 or more, and the absorption ratio was 0.7 or more.

In the production method of the present invention, since the raw materials can be sequentially added in one reaction vessel, the double fluoride phosphor can be produced with reasonable and high productivity.

1‧‧‧ container

2‧‧‧Agitating mechanism

3,7,9‧‧‧with door fittings

4‧‧‧ pump

5‧‧‧ supply slot

6‧‧‧Powder supply device

8‧‧‧Drip tank

Fig. 1 is a schematic view showing an example of a manufacturing apparatus used in the production of the production method of the present invention.

[Best Mode for Carrying Out the Invention]

The production method of the present invention is to obtain A ₂ MF ₆ : Mn (I) of the following formula (I) (wherein M is one or two selected from Si, Ti, Zr, Hf, Ge, and Sn) In the above tetravalent element, A is an alkali metal selected from Li, Na, K, Rb, and Cs and containing at least one or two or more kinds of Na and/or K. A method of forming a complex fluoride phosphor.

Here, M is preferably Si, Ti or Ge, especially Si or Ti, and A is preferably Na or K.

The production method of the present invention is to sequentially dissolve various components as raw materials in water, and finally obtain the red fluorescent light of the above formula (I) from the obtained aqueous solution. Body precipitater.

At this time, as the raw material, an M source (a tetravalent element source), an A source (alkali metal source), a Mn source, a fluorine source, and further a hydrogen fluoride as a reaction medium are used. These materials are dissolved in water to cause a reaction to obtain a precipitate of a phosphor. Although the order of dissolution is not limited, it is preferred to add the alkali metal A after all the other is dissolved. Further, in order to make it easy to dissolve, it is preferred to add hydrogen fluoride to the M source and the Mn source.

As a source of the tetravalent element M, a fluoride, an oxide, a hydroxide, a carbonate, or the like can be used, and an oxide or a fluoride is preferable. These may be used alone or in combination of two or more. For example, SiO ₂ , TiO ₂ or the like can be mentioned. When these are dissolved in water together with the aqueous solution of hydrogen fluoride, it is substantially an aqueous solution containing the polyfluoride of the element M. Alternatively, it may be used as a solution of a polyfluoride salt such as H ₂ SiF ₆ .

As a raw material of manganese, a fluoride, a carbonate, an oxide, a hydroxide, or the like of manganese may be used, but it is preferably used in the form of a compound containing a compound of A and Mn (fluoride, oxide, chloride, etc.). The oxidation state and the point of easy dissolution are preferably a double fluoride represented by A ₂ MnF ₆ or a double oxide represented by A ₂ MnO ₃ . Examples thereof include K ₂ MnF ₆ and the like.

As a source of the alkali metal A (A is one or more selected from Li, Na, K, Rb, and Cs, and at least Na and/or K), the fluoride AF, the hydrogen fluoride salt AHF ₂ , and the nitric acid can be used. The selected compounds of salt ANO ₃ , sulfate A ₂ SO ₄ , hydrogen sulfate AHSO ₄ , carbonate A ₂ CO ₃ , hydrogencarbonate AHCO ₃ and hydroxide AOH are dissolved in hydrogen fluoride (hydrogen fluoride solution) as necessary. After water, it is prepared as an aqueous solution. On the other hand, solids may be composed of fluoride AF, hydrogen fluoride salt AHF ₂ , nitrate ANO ₃ , sulfate A ₂ SO ₄ , hydrogen sulfate AHSO ₄ , carbonate A ₂ CO ₃ , hydrogencarbonate AHCO ₃ and hydrogen. The compound selected for the oxide AOH is prepared as a solid. Preferred are fluorides or hydrogen fluoride salts.

As a suitable method for producing a double fluoride phosphor using the above raw materials, water is first added to the reaction vessel and hydrogen fluoride is introduced therein. In this case, the concentration of the hydrogen fluoride acid is preferably 10 to 50% by mass, particularly preferably 15 to 45% by mass, based on the substrate solution to be described later.

Next, a compound containing M (however, M is as described above) is introduced, followed by stirring and dissolution. The concentration of the compound of the above M in the above aqueous solution of hydrogen fluoride is 0.02 to 1.0 mol/liter in the substrate solution to be described later, preferably 0.05 to 0.5 mol/liter.

Then, one or two or more kinds of a compound containing A (but A is the same as above) and a compound containing Mn, preferably a compound containing A and Mn, are added, and then stirred and dissolved to prepare a matrix solution. At this time, the concentration of A and the concentration of Mn are each 0.00005 to 0.4 mol/liter in the matrix solution, particularly preferably 0.0001 to 0.2 mol/liter.

Finally, while stirring the base solution, a fluoride of A (but, A is as described above) or a hydrofluoric acid solution in which the fluoride is dissolved is added as an additive. In this case, examples of the fluoride include sodium fluoride, sodium hydrogen fluoride, potassium fluoride, and potassium hydrogen fluoride, and particularly preferably sodium hydrogen fluoride or potassium hydrogen fluoride. Further, the concentration of the hydrofluoric acid in the hydrogen fluoride acid solution is the same as or higher than the concentration of A in the case where a fluoride or a hydrogen fluoride is used as the A raw material. It is preferable that the above is more than twice the concentration of A. When a fluoride or a hydrogen fluoride salt is used as the A raw material, the concentration of the hydrogen fluoride acid is not limited. The concentration of the alkali metal A is 0.25 mol/liter or more, particularly preferably 0.5 mol/liter or more. Further, the amount of the alkali metal A to be added is preferably 2.0 to 10.0 (mole ratio), more preferably 2.0 to 5.0 (mole ratio), based on the total of M and Mn in the matrix solution.

In the concentration of the state in which the reaction materials are all mixed, the total concentration of the elements M and Mn is preferably 0.02 to 1.0 mol/liter. More preferably 0.05 to 0.5 m / liter.

Further, the ratio of the total of the tetravalent element M to Mn in the state in which the reaction materials are all mixed with the alkali metal A is A/(M+Mn)=2.0 to 10.0 (mole ratio), particularly 2.0 to 5.0 (mo Ear ratio) is better.

The ratio of Mn added to the reaction system with respect to M is preferably Mn/(M+Mn)=0.002 to 0.4 (mole ratio), particularly preferably 0.005 to 0.2 (mole ratio).

The temperature of the liquid in the reaction can be carried out by heating or cooling in the range of -20 to 100 °C. The suppression of the volatilization of the hydrogen fluoride gas is preferably 60 ° C or lower, particularly preferably 50 ° C or lower.

The reaction apparatus for realizing the production method of the present invention is required to include a reaction vessel, an acid solution supply tank, a stirrer, a drip tank, a pump, a powder supply device, and a slurry discharge pipe.

More specifically, as a manufacturing apparatus, a solution supply tank 5 having a valve assembly 3 and a pump 4 for supplying various solutions and a powder are disposed in one main reaction container 1 having a stirring mechanism 2 as shown in Fig. 1 . The supply device 6 has a drip tank 8 with a valve fitting 7 attached thereto, and the discharge contains It is preferable that the slurry of the produced complex fluoride phosphor is attached to the valve fitting 9 of the valve.

The mixer is installed in the reaction vessel. The stirring shaft is attached to the stirring shaft, and each stirring shaft is preferably rotated. The shape of the stirring blade can be arbitrarily selected, and examples thereof include a flat plate shape (no or oblique), an anchor shape, and the like. In the reaction, the solution in the reaction vessel is stirred in the range of from 0.5 times/second to 100 times/second. It is preferably 1 to 10 times/second.

The dropping tank may be optionally disposed above the reaction vessel, and the liquid may be added to the reaction vessel or a pump or the like by opening the shutter, and the liquid may be added to the reaction vessel to control the flow rate. When the hydrofluoric acid solution in which the alkali metal A is dissolved is dropped into the solution, it is preferably added to the solution in an amount of 1/500 to 1/10 of the total amount of the hydrogen fluoride solution. The speed is preferably 1/200 to 1/20.

In order to add the powder raw material to the reaction liquid in the reaction vessel, a powder supply device is necessary. In order to adjust the state of the substance to be dissolved, or to add the raw material of the alkali metal A to the powder, the powder supply device is preferably a mechanism capable of controlling the supply amount of the powder. In order to perform solid-liquid separation of the phosphor obtained by precipitation, a slurry discharge pipe is required. The discharged slurry is subjected to solid-liquid separation by filtration, centrifugation, decantation or the like.

The complex fluoride phosphor of the present invention can be obtained as a solid product. The solid product after solid-liquid separation may be subjected to washing, solvent substitution or the like as necessary, and may be dried by vacuum drying or the like.

The phosphor obtained by the production method of the present invention is made of Mn The complex fluoride phosphor which is a luminescent center exhibits red luminescence due to blue (400 to 480 nm, as a case of 450 nm) light excitation. It exhibits the strongest peak before and after 630 nm and is an illuminating spectrum composed of peaks with several sharp line widths. When it is produced under the standard conditions of the present invention, the absorbance for light of 450 nm is 0.7 or more, preferably 0.71 to 0.85, and the internal quantum efficiency is 0.8 or more, preferably 0.82 to 0.92, preferably as a blue LED. A red phosphor for the white LED of the excitation source.

[Examples]

The present invention will be more specifically illustrated by the following examples and comparative examples, but the invention is not limited thereto. Further, Examples 1 to 3 are examples in which K ₂ SiF ₆ : Mn and Example 4 are K ₂ TiF ₆ : Mn.

[Reference example] [Modulation of K ₂ MnF ₆ ]

It is prepared by the following method according to the method described in Maruzen Co., Ltd., the Japanese Chemical Society, the New Experimental Chemistry Lecture 8 "Synthesis of Inorganic Compounds III", 1977, and 1166 pages (Non-Patent Document 1).

A partition (separator) of a fluororesin-based ion exchange membrane was placed in the center of the reaction vessel made of a vinyl chloride resin, and an anode and a cathode each composed of a platinum plate were provided in each of the two chambers holding the ion exchange membrane. A hydrofluoric acid aqueous solution in which manganese (II) fluoride was dissolved was added to the anode side of the reaction vessel, and a hydrofluoric acid aqueous solution was added to the cathode side. The two poles were connected to a power source, and electrolysis was performed at a voltage of 3 V and a current of 0.75 A. After the completion of the electrolysis, a solution of potassium fluoride saturated with an aqueous solution of hydrogen fluoride was added to the reaction liquid on the anode side. The resulting yellow solid product was filtered and recovered to obtain K ₂ MnF ₆ .

[Example 1]

The reaction apparatus shown in Fig. 1 was prepared. First, a water amount of 10,000 cm ^{3 was} added to the reaction vessel. The stirrer provided in the reaction vessel was started, supplied to the tank from the acid solution while stirring, and 50% of hydrogen fluoride acid (SA-X, 50% HF manufactured by Stella-Chemifa) was used at 25,000 cm ³ , and the liquid was fed to the reaction vessel. Under continuous stirring, 810 g of cerium oxide (Nipsil VN3, SiO ₂ manufactured by Tosoh Chemical Co., Ltd.) was supplied in small portions from the powder supply device on the upper side of the reaction vessel. The HF solution in the reaction vessel dissolves SiO ₂ . Next, 200 g of K ₂ MnF ₆ produced by the method of the above Reference Example was supplied from the powder supply device to the reaction container, and dissolved in the container.

At this time, 10,000 cm ³ of 50% HF was added to the dropping tank, and potassium fluoride (manufactured by Stella-Chemifa anhydrous potassium fluoride, KF) 2,036 g was added thereto to dissolve. The number of rotations of the agitator set in the reaction vessel was set to 200 rotations/min (3.33 rotations/second). The KF solution was dropped from the dropping tank at a constant speed for 1 minute and 40 seconds. The liquid in the reaction vessel produced a pale orange precipitate.

After about 10 minutes, the slurry of the slurry discharged from the lower part of the reaction vessel was opened, and the slurry was sent to a vacuum filter connected to the pipe to filter the precipitate. After sufficient deliquoring, the amount of acetone which can be immersed in a cake-like precipitate is added and washed. The cake was recovered and dried under vacuum. 2,850 g of a pale orange powder K ₂ SiF ₆ :Mn phosphor was obtained.

The particle size distribution of the obtained powder product was measured by a gas flow dispersion type laser diffraction particle size distribution analyzer (HELOS & RODOS, manufactured by Sympatec Co., Ltd.). As a result, particles having a particle diameter of 15.9 μm or less are 10% (D10 = 15.9 μm) of the entire volume, and particles having a particle diameter of 34.7 μm or less are 50% (D50 = 34.7 μm) of the entire volume, and particles having a particle diameter of 49.8 μm or less. It is 90% of the full volume (D90 = 49.8 μm).

[Embodiment 2]

In the step of the first embodiment, instead of SiO ₂ being supplied from the powder supply device, the solution was dissolved, and 40% of fluoroantimonic acid (manufactured by Morita Chemical Industry Co., Ltd., 40% H ₂ SiF ₆ ) was supplied from the acid solution supply tank, 3,520 cm. Mix after ³ . Thereafter, the same operation as in Example 1 was carried out to obtain 2,860 g of a phosphor powder of K ₂ SiF ₆ :Mn. The particle size distribution measured in the same manner as in Example 1 was D10 = 16.1 μm, D50 = 34.9 μm, and D90 = 49.2 μm.

[Example 3]

In the step of Example 1, the KF was dissolved in 50% HF and added to the dropping tank, and instead of this, potassium hydrogen fluoride (potassium fluoride of potassium sulfate, KHF ₂ made by Stella-Chemifa) 2,737 g from the powder supply device was added. After the supply, the reaction is allowed. The number of rotations of the mixer was adjusted to 300 rotations/min (5 rotations/second), and the mixture was stirred, and the solution of the KHF ₂ powder was added to the reaction vessel by the powder supply device for 1 minute. In the reaction vessel, KHF ₂ reacts while dissolving to form a pale orange precipitate. After stirring for about 15 minutes, the mixture was filtered, collected, and dried in the same manner as in Example 1 to obtain 2,835 g of a phosphor powder of K ₂ SiF ₆ :Mn. The particle size distribution measured in the same manner as in Example 1 was D10 = 13.5 μm, D50 = 32.9 μm, and D90 = 50.8 μm.

[Example 4]

The reaction apparatus shown in Fig. 1 was used in the same manner as in Examples 1 to 3. First, a water volume of 20,000 cm ^{3 was} added to the reaction vessel. The mixer provided in the reaction vessel was started, and the tank was supplied from the acid solution while stirring, and a pump was used for 50% HF 15,000 cm ³ , and the liquid was fed to the reaction vessel. Under continuous stirring, 1,433 g of titanium dioxide (a high-purity product TCA-123P, TiO ₂ manufactured by Nippon Chemical Industry Co., Ltd.) was supplied from a small amount of the powder supply device located on the upper side of the reaction vessel. The HF solution in the reaction vessel dissolves TiO ₂ . Next, 356 g of K ₂ MnF ₆ produced by the method of the above Reference Example was supplied from a powder supply device to a reaction container, and dissolved in a container.

At this time, 5,000 cm ³ of 50% HF and water of 5,000 cm ^{3 were} added to the dropping tank, and KF ³ was added thereto, and 556 g was dissolved. The number of rotations of the agitator set in the reaction vessel was set to 200 rotations/min (3.33 rotations/second). The KF solution was dropped from the dropping tank at a constant speed for 1 minute and 35 seconds. The liquid in the reaction vessel produced a pale orange precipitate.

After about 10 minutes, the filtration operation was carried out in the same manner as in Example 1. Further, the mixture was deliquored, washed with acetone, and dried to obtain 3,980 g of a pale orange powder phosphor of K ₂ TiF ₆ : Mn. The particle size distribution measured in the same manner as in Example 1 was D10 = 16.1 μm, D50 = 38.9 μm, and D90 = 69.3 μm.

[Comparative Example 1]

So that 40% of H ₂ SiF ₆ aqueous solution of 23cm ³ 266cm ³ is first mixed with 50% HF. Into the above, 1.33 g of K ₂ MnF ₆ powder prepared by the method of the above Reference Example was added, and the mixture was stirred and dissolved (solution A).

Further, 21.05 g of potassium hydrogen fluoride was mixed with 50% HF 68 cm ³ and pure water 127 cm ^{3 to} dissolve (solution B).

Solution A was stirred at room temperature (16 ° C) while solution B (17 ° C) was added. The temperature of the liquid became 26 ° C, and a pale orange precipitate (K ₂ SiF ₆ : Mn) was produced. After further stirring for 10 minutes, the precipitate was filtered through a Buchner funnel and degreased as much as possible. Further, it was washed with acetone, dehydrated, and vacuum dried to obtain a powder product K ₂ SiF ₆ : Mn 18.01 g.

The particle size distribution measured in the same manner as in Example 1 was D10 = 10.5 μm, D50 = 23.8 μm, and D90 = 35.4 μm.

[Comparative Example 2]

A 40% aqueous solution of H ₂ SiF ₆ 23 cm ^{3 was} first mixed with 50% HF 146 cm ³ . Into the above, 1.33 g of K ₂ MnF ₆ powder prepared by the method of the above Reference Example was added, and the mixture was stirred and dissolved (solution A).

Further, 21.05g of potassium hydrogen fluoride and 50% HF 180cm ^3, 90cm ³ water mixed, dissolved (solution B).

Solution B was added to Solution A (17 ° C) while stirring at room temperature (16 ° C). The temperature of the liquid became 25 ° C, and a pale orange precipitate (K ₂ SiF ₆ : Mn) was formed. After further stirring for 10 minutes, the precipitate was filtered through a Buchner funnel and degreased as much as possible. Further, it was washed with acetone, dehydrated, and vacuum dried to obtain a powder product K ₂ SiF ₆ : Mn 17.88 g.

The particle size distribution measured in the same manner as in Example 1 was D10 = 4.2 μm, D50 = 11.3 μm, and D90 = 17.3 μm.

[Experimental example]

The luminescence spectrum, the absorptance, and the quantum efficiency of the powder sample obtained in the examples were measured using an quantum efficiency measuring apparatus QE1100 (manufactured by Otsuka Electronics Co., Ltd.) at an excitation wavelength of 450 nm. The absorption rate and quantum efficiency are shown in Table 1.

Claims (6)

A method for producing a complex fluoride phosphor characterized by the following formula (I) A ₂ MF ₆ : Mn (I) (wherein M is selected from Si, Ti, Zr, Hf, Ge, and Sn One or two or more kinds of tetravalent elements, and A is Mn represented by Li, Na, K, Rb, and Cs and is an alkali metal containing at least one or two or more kinds of Na and/or K. In the production of the activated complex fluoride red phosphor, various components as raw materials are sequentially dissolved in water, and the red phosphor is finally precipitated in the solution from the obtained aqueous solution. The method for producing a complex fluoride phosphor according to claim 1, wherein water is prepared in a container, and hydrogen fluoride is introduced therein, and then a compound containing M (however, M is as described above) is introduced, followed by stirring and dissolving, and then, A compound containing A (but A is the same as above) and a compound containing Mn or a compound containing A (but A is the same as above) and Mn are charged, and then stirred and dissolved to prepare a matrix solution, and finally, the matrix solution is stirred while being added. A (hereinafter, A and M) is added to the fluoride or the hydrogen fluoride solution in which the fluoride is dissolved, and then A ₂ MF ₆ : Mn (but A and M are the same as above) is precipitated in the matrix solution. . The method for producing a complex fluoride phosphor according to claim 2, wherein the substrate solution is stirred by a stirrer at a number of revolutions in the range of 0.5 to 100 times/second when the additive is added. The method for producing a complex fluoride phosphor according to claim 2, Here, the additive is added in a predetermined amount in the range of 1/500 to 1/10 of the total amount of the additive. The method for producing a complex fluoride phosphor according to claim 1, which is used in a main reaction container having a stirring mechanism, and is provided with a valve for supplying various solutions, a pump, a powder supply device, and a discharge. A device for attaching a valve with a slurry of the produced complex fluoride phosphor to produce a double fluoride phosphor. A red double-fluoride phosphor for a blue LED represented by the formula A ₂ MF ₆ : Mn (however, A and M are the same as above), which is characterized by the production method according to any one of claims 1 to 5. The internal quantum efficiency was 0.8 or more and the absorption rate was 0.7 or more.