Fluoride phosphor, production method thereof and light-emitting device

Abstract

To provide a fluoride phosphor capable of improving reliability of a light-emitting device.SOLUTION: It is a fluoride phosphor that includes fluoride particles and a fluorine compound containing zirconium arranged on at least a part of the surface of the fluoride particles. The fluoride particles comprise at least one element M selected from the group consisting of group 4 elements, group 13 elements, and group 14 elements, at least one species selected from the group consisting of alkali metals and ammonium ions, manganese, and fluorine atoms, where when the total mole number of alkali metals and ammonium ions is 2, the mole number of manganese is more than 0 and less than 0.2, the total mole number of element M is more than 0.8 and less than 1, and the mole number of fluorine atoms is more than 5 and less than 7.SELECTED DRAWING: Figure 2A

Description

[Technical Field]

[0001] The present disclosure relates to a fluoride phosphor, a method for producing the same, and a light-emitting device. [Background technology]

[0002] Light-emitting devices that combine a light-emitting element and a phosphor are used in a wide range of fields, such as lighting, vehicle lighting, displays, and LCD backlights. For example, phosphors used in light-emitting devices for LCD backlights are required to have high color purity, i.e., a narrow half-width of the emission peak. Manganese-doped fluoride phosphors are known as red-emitting phosphors with a narrow half-width of the emission peak.

[0003] For example, Patent Document 1 describes coating manganese-doped red phosphors with aluminum oxide or the like to reduce the problem of instability due to deterioration of the manganese-doped red phosphors, and further describes a light-emitting device equipped with a fluorescent member containing the coated manganese-doped red phosphor. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Special Publication No. 2019-525974 Summary of the Invention [Problem to be solved by the invention]

[0005] In a light emitting device including a wavelength conversion member containing a manganese-containing fluoride phosphor, the reliability of the light emitting device may be reduced depending on the environment in which the light emitting device is used. One aspect of the present disclosure aims to provide a fluoride phosphor and a method for manufacturing the same that can further improve the reliability of the light emitting device. [Means for solving the problem]

[0006] The first aspect is a fluoride phosphor comprising fluoride particles and a fluorine compound containing zirconium disposed on at least a portion of the surface of the fluoride particles. The fluoride particles comprise element M, which comprises at least one element selected from the group consisting of Group 4 elements, Group 13 elements, and Group 14 elements, at least one element selected from the group consisting of alkali metals and ammonium ions, manganese, and fluorine atoms, and has a composition in which, when the total number of moles of alkali metals and ammonium ions is taken as 2, the number of moles of manganese is more than 0 and less than 0.2, the total number of moles of element M is more than 0.8 and less than 1, and the number of moles of fluorine atoms is more than 5 and less than 7.

[0007] The second aspect is a method for producing a fluoride fluorescent material, comprising: preparing fluoride particles having a composition containing element M including at least one element selected from the group consisting of Group 4 elements, Group 13 elements, and Group 14 elements, at least one element selected from the group consisting of alkali metals and ammonium ions, manganese, and fluorine atoms, where, when the total number of moles of alkali metals and ammonium ions is 2, the number of moles of manganese is more than 0 and less than 0.2, the total number of moles of element M is more than 0.8 and less than 1, and the number of moles of fluorine atoms is more than 5 and less than 7; and contacting the prepared fluoride particles with a solution containing complex ions including zirconium and fluoride ions to dispose a fluorine compound containing zirconium on at least a portion of the surface of the fluoride particles.

[0008] A third aspect is a light emitting device comprising the fluoride phosphor of the first aspect and a light source having an emission peak wavelength in the range of 380 nm to 485 nm. [Effects of the Invention]

[0009] According to one aspect of the present disclosure, it is possible to provide a fluoride phosphor that can further improve the reliability of a light emitting device, and a method for manufacturing the same. [Brief explanation of the drawings]

[0010] [Figure 1]FIG. 1 is a schematic cross-sectional view showing an example of a light-emitting device using a fluoride fluorescent material. [Figure 2A] 2 is an example of a scanning electron microscope image of the fluoride phosphor according to Example 1. [Figure 2B] 10 is an example of a scanning electron microscope image of a fluoride phosphor according to Example 3. [Figure 3] 1 is an example of an X-ray diffraction spectrum of a fluoride phosphor. DETAILED DESCRIPTION OF THE INVENTION

[0011] As used herein, the term "process" refers not only to an independent process, but also to processes that cannot be clearly distinguished from other processes, as long as the intended purpose of the process is achieved. Furthermore, when multiple substances corresponding to each component are present in the composition, the content of each component refers to the total amount of those substances present in the composition, unless otherwise specified. Furthermore, the upper and lower limits of the numerical ranges described herein can be arbitrarily selected and combined from the numerical values ​​exemplified as numerical ranges. In this specification, in formulas representing the composition of phosphors or luminescent materials, multiple elements separated by a comma (,) mean that at least one of those multiple elements is contained in the composition. In addition, in formulas representing the composition of phosphors, the part before the colon (:) represents the host crystal, and the part after the colon (:) represents the activator element. In this specification, the relationship between color names and chromaticity coordinates, the relationship between the wavelength range of light and the color name of monochromatic light, etc., follows JIS Z8110. The half width of a phosphor refers to the wavelength width (full width at half maximum; FWHM) of the emission spectrum of the phosphor, where the emission intensity is 50% of the maximum emission intensity. Hereinafter, embodiments of the present invention will be described in detail. However, the embodiments shown below are intended to exemplify fluoride phosphors, their manufacturing methods, and light-emitting devices in order to embody the technical concept of the present invention, and the present invention is not limited to the fluoride phosphors, their manufacturing methods, and light-emitting devices shown below.

[0012] Fluoride Phosphors The fluoride phosphor may include fluoride particles and a fluorine compound containing zirconium disposed on at least a portion of the surface of the fluoride particles. The fluoride particles may include, in their composition, an element M including at least one element selected from the group consisting of Group 4 elements, Group 13 elements, and Group 14 elements, at least one element selected from the group consisting of alkali metals and ammonium ions, manganese, and fluorine atoms. The composition of the fluoride particles may be such that, when the total number of moles of alkali metals and ammonium ions is 2, the number of moles of manganese is greater than 0 and less than 0.2, the total number of moles of element M is greater than 0.8 and less than 1, and the number of moles of fluorine atoms is greater than 5 and less than 7.

[0013] A light-emitting device including a fluoride phosphor, which is constructed by disposing a fluorine compound containing zirconium on the surface of fluoride particles, which are a fluorescent substance, can reduce or prevent luminous flux reduction, color change, etc., even in use environments such as high temperature and high humidity, and can exhibit excellent reliability. This can be thought of, for example, as follows: By disposing a fluorine compound containing zirconium, which does not contain manganese ions that can cause luminous flux reduction and color change, on the surface of the fluoride particles, degradation of the fluoride phosphor in high temperature or high temperature and high humidity environments is suppressed.

[0014] The fluoride particles constituting the fluoride phosphor need only contain a fluorescent material activated with manganese (Mn), and may consist solely of a fluorescent material activated with Mn. The composition of the fluoride particles may be such that, when the total number of moles of alkali metal and ammonium ions is 2, the number of moles of Mn is greater than 0 and less than 0.2, preferably 0.01 to 0.12. Furthermore, the composition of the fluoride particles may be such that, when the total number of moles of alkali metal and ammonium ions is 2, the number of moles of element M is greater than 0.8 and less than 1, preferably 0.88 to 0.99. The composition of the fluoride particles may be such that, when the total number of moles of alkali metal and ammonium ions is 2, the number of moles of F is greater than 5 and less than 7, preferably 5.9 to 6.1. The composition of the fluoride particles can be measured, for example, by inductively coupled plasma (ICP) atomic emission spectroscopy.

[0015] The alkali metal in the composition of the fluoride particles may include at least one selected from the group consisting of lithium (Li), sodium (Na), potassium (K), rubidium (Rb), and cesium (Cs). The alkali metal may include at least potassium (K) and may also include at least one selected from the group consisting of lithium (Li), sodium (Na), rubidium (Rb), and cesium (Cs). The ratio of the number of moles of K to the total number of moles of alkali metals and ammonium ions in the composition may be, for example, 0.90 or more, preferably 0.95 or more, or 0.97 or more. The upper limit of the ratio of the number of moles of K may be, for example, 1 or 0.995 or less. In the composition of the fluoride particles, ammonium ions (NH4) may be used instead of alkali metals. + When ammonium ions are contained, the ratio of the number of moles of ammonium ions to the total number of moles of alkali metal and ammonium ions in the composition may be, for example, 0.10 or less, preferably 0.05 or less, or 0.03 or less. The lower limit of the ratio of the number of moles of ammonium ions may be, for example, more than 0, preferably 0.005 or more.

[0016] Element M in the composition of the fluoride particles contains at least one selected from the group consisting of Group 4 elements, Group 13 elements, and Group 14 elements. Examples of Group 4 elements include titanium (Ti), zirconium (Zr), hafnium (Hf), etc., and may contain at least one selected from the group consisting of these. Examples of Group 13 elements include boron (B), aluminum (Al), gallium (Ga), indium (In), thallium (Tl), etc., and may contain at least one selected from the group consisting of these. Examples of Group 14 elements include carbon (C), silicon (Si), germanium (Ge), tin (Sn), etc., and may contain at least one selected from the group consisting of these. Element M may contain at least one of the Group 14 elements, preferably may contain at least one of Si and Ge, and more preferably may contain at least Si. Also, element M may contain at least one of the Group 13 elements and at least one of the Group 14 elements, preferably may contain at least Al and at least one of Si and Ge, and more preferably may contain at least Al and Si.

[0017] In the composition of the fluoride particles, the total molar number of element M and Mn may be 0.9 or more and 1.1 or less, preferably 0.95 or more and 1.05 or less, or 0.97 or more and 1.03 or less, with respect to the total molar number 2 of alkali metals and ammonium ions.

[0018] The composition of the fluoride particles may be a composition represented by the following formula (1). A c [M 1-b Mn b F d (1) In formula (1), A may contain at least one selected from the group consisting of Li, Na, K, Rb, Cs, and NH4. M contains at least Si and may further contain at least one element selected from the group consisting of Group 4 elements, Group 13 elements, and Group 14 elements. Mn may be tetravalent Mn ions. b may satisfy 0 < b < 0.2, and c is [M​​1-b Mn b F d is the absolute value of the charge of the ion, and d may satisfy 5 < d < 7.

[0019] A in formula (1) contains at least K and may further contain at least one selected from the group consisting of Li, Na, Rb, Cs, and NH4. + The ratio of the number of moles of K to the total number of moles of A in the composition may be, for example, 0.90 or more, preferably 0.95 or more, or 0.97 or more. The upper limit of the ratio of the number of moles of K may be, for example, 1 or 0.995 or less.

[0020] b in formula (1) is preferably 0.005 or more and 0.15 or less, 0.01 or more and 0.12 or less, or 0.015 or more and 0.1 or less. c may be, for example, 1.8 or more and 2.2 or less, preferably 1.9 or more and 2.1 or less, or 1.95 or more and 2.05 or less. d is preferably 5.5 or more and 6.5 or less, 5.9 or more and 6.1 or less, 5.95 or more and 6.05 or less, or 5.97 or more and 6.03 or less.

[0021] Furthermore, the fluoride particles may have a theoretical composition represented by the following formula (1a). A2MF6:Mn (1a) In formula (1a), A may contain at least one selected from the group consisting of Li, Na, K, Rb, Cs, and NH4. + M contains at least Si and may further contain at least one element selected from the group consisting of Group 4 elements, Group 13 elements, and Group 14 elements. Mn may be tetravalent Mn ions.

[0022] In one aspect of the composition of the fluoride particles, the first composition may contain at least one selected from the group consisting of Group 4 elements and Group 14 elements as element M, preferably may contain at least one selected from the group consisting of Group 14 elements, more preferably may contain at least one of Si and Ge, and still more preferably may contain at least Si. Further, in the first composition of the fluoride particles, the total molar number of Si, Ge and Mn may be 0.9 or more and less than or equal to 1.1 with respect to the total molar number 2 of alkali metals and ammonium ions, preferably may be 0.95 or more and less than or equal to 1.05, or may be 0.97 or more and less than or equal to 1.03.

[0023] The first composition of the fluoride particles may be a composition represented by the following formula (2). A 1 q [M 1 1-p Mn p F r (2)<0​​​​​​​​​​​​​​​​​​​​​​​​​​​The ratio of the number of moles of ammonium ions to the total number of moles may be, for example, 0.10 or less, preferably 0.05 or less, or 0.03 or less. The lower limit of the ratio of the number of moles of ammonium ions may be, for example, more than 0, preferably 0.005 or more.

[0026] In formula (2), p is preferably 0.005 to 0.15, 0.01 to 0.12, or 0.015 to 0.1. q may be, for example, 1.8 to 2.2, preferably 1.9 to 2.1, or 1.95 to 2.05. r is preferably 5.5 to 6.5, 5.9 to 6.1, 5.92 to 6.05, or 5.95 to 6.025.

[0027] Furthermore, the fluoride particles of the first composition may have a first theoretical composition represented by the following formula (2a). A 1 2M 1 F6:Mn (2a)

[0028] In formula (2a), A 1 are Li, Na, K, Rb, Cs and NH4 + M 1 contains at least one of Si and Ge, and may further contain at least one element selected from the group consisting of elements of Group 4 and elements of Group 14. Mn may be a tetravalent Mn ion.

[0029] A second composition, which is one embodiment of the composition of the fluoride particles, may contain at least one selected from the group consisting of a Group 4 element and a Group 14 element as element M, and at least one of a Group 13 element, preferably at least one selected from the group consisting of a Group 14 element and at least one of a Group 13 element, more preferably may contain at least Si and Al. Further, in the second composition of the fluoride particles, the total molar number of Si, Al and Mn may be 0.9 or more and 1.1 or less, preferably 0.95 or more and 1.05 or less, or 0.97 or more and 1.03 or less, with respect to the total molar number 2 of alkali metal and ammonium ions. Furthermore, in the second composition of the fluoride particles, the molar number of Al may be more than 0 and 0.1 or less, preferably more than 0 and 0.03 or less, 0.002 or more and 0.02 or less, or 0.003 or more and 0.015 or less, with respect to the total molar number 2 of alkali metal and ammonium ions.

[0030] The second composition of the fluoride particles may be a composition represented by the following formula (3). A 2 t [M 2 1-s Mn s F u (3)

[0031] In formula (3), A 2 contains at least K, and may further contain at least one selected from the group consisting of Li, Na, Rb, Cs and NH4. M + contains at least Si and Al, and may further contain at least one element selected from the group consisting of a Group 4 element, a Group 13 element and a Group 14 element. Mn may be a tetravalent Mn ion. s may satisfy 0 < s < 0.2, and t is the absolute value of the charge of the [M 2 Mn 2 1-s Mn s F u ion, and u may satisfy 5 < u < 7.

[0032] When A in formula (3) contains an ammonium ion, A in the composition 22 The ratio of the number of moles of ammonium ions to the total number of moles may be, for example, 0.10 or less, preferably 0.05 or less, or 0.03 or less. The lower limit of the ratio of the number of moles of ammonium ions may be, for example, more than 0, preferably 0.005 or more.

[0033] In formula (3), s may preferably be 0.005 or more and 0.15 or less, 0.01 or more and 0.12 or less, or 0.015 or more and 0.1 or less. t may be, for example, 1.8 or more and 2.2 or less, preferably 1.9 or more and 2.1 or less, or 1.95 or more and 2.05 or less. u may preferably be 5.5 or more and 6.5 or less, 5.9 or more and 6.1 or less, 5.92 or more and 6.05 or less, or 5.95 or more and 6.025 or less.

[0034] Furthermore, the fluoride particles of the second composition may have a second theoretical composition represented by the following formula (3a). A 2 2Si 1-v Al v F 6-v :Mn (3a)

[0035] In formula (3a), A 2 contains at least K, and may further contain at least one selected from the group consisting of Li, Na, Rb, Cs, and NH4 + v may satisfy 0 < v < 1, preferably 0.005 < v < 0.03. Mn may be tetravalent Mn ions.

[0036] The fluoride phosphor may contain a fluorine compound containing zirconium disposed on at least a portion of the surface of a fluoride particle. The fluorine compound may cover the surface of the fluoride particle in the form of a film, or may be disposed on the surface of the fluoride particle as a fluorine compound layer. The coverage of the fluoride particle in the fluoride phosphor with the fluorine compound may be, for example, 50% or more, preferably 80% or more, or 90% or more. The coverage of the fluoride particle with the fluorine compound is calculated as the ratio of the area covered by the fluorine compound to the surface area of ​​the fluoride particle.

[0037] The fluorine compound may be any compound containing zirconium and fluorine atoms in its composition, and may further contain at least one selected from the group consisting of alkali metals and ammonium ions. When the fluorine compound contains alkali metals or ammonium ions in its composition, it may contain at least potassium as the alkali metal. When the fluorine compound contains potassium in its composition, the molar ratio of potassium to alkali metals and ammonium ions may be, for example, 0.8 or more, preferably 0.9 or more, or 0.95 or more. The fluorine compound may further contain, in addition to zirconium, a Group 4 atom other than zirconium, such as titanium, in its composition. When the fluorine compound contains a Group 4 atom other than zirconium in its composition, the molar ratio of the Group 4 atom other than zirconium to zirconium may be, for example, 0.1 or less, preferably 0.01 or less, or 0.001 or less.

[0038] The fluorine compound may include at least a compound having a composition represented by, for example, AZrF5, where A is Li, Na, K, Rb, Cs, and NH4 + A may contain at least one selected from the group consisting of K, Li, Na, Rb, Cs, and NH4 +The composition may further contain at least one selected from the group consisting of, or may be substantially K. Here, "substantially" means that unavoidable impurities are allowed, and the impurity content is, for example, 5 mol% or less, 1 mol% or less, or 0.1 mol% or less. The ratio of the number of moles of K to the total number of moles of A in the composition may be, for example, 0.90 or more, preferably 0.95 or more, or 0.97 or more. The upper limit of the ratio of the number of moles of K may be, for example, 1 or 0.995 or less.

[0039] The content of the fluorine compound in the fluoride phosphor may be, for example, 0.1% by mass or more and 10% by mass or less, and preferably 0.3% by mass or more, 0.5% by mass or more, or 0.8% by mass or more, calculated as zirconium. The content of the fluorine compound may be 5% by mass or less, or 2% by mass or less. When the content of the fluorine compound is within the above range, the reliability of the light-emitting device tends to be further improved. Furthermore, a decrease in powder brightness tends to be suppressed.

[0040] The volume-based median diameter of the fluoride phosphor may be, for example, 5 μm or more and 90 μm or less, preferably 10 μm or more and 70 μm or less, or 15 μm or more and 50 μm or less, from the viewpoint of improving brightness. The particle size distribution of the fluoride phosphor may, for example, exhibit a single-peak particle size distribution, preferably a single-peak particle size distribution with a narrow distribution width, from the viewpoint of improving brightness. Specifically, in the volume-based particle size distribution, the particle size corresponding to 10% of the cumulative volume from the small diameter side is defined as D 10 , the particle size corresponding to 90% of the cumulative volume is D 90 Then, D 10 D against 90 The ratio (D 90 / D 10 ) may be, for example, 3.0 or less. The volume-based median diameter is a particle size corresponding to 50% of the cumulative volume from the small diameter side in a volume-based particle size distribution, and the volume-based particle size distribution is measured using a laser diffraction particle size distribution analyzer.

[0041] The fluoride phosphor may be, for example, a phosphor activated with tetravalent manganese, and may absorb light in the short wavelength region of visible light to emit red light. The light irradiated onto the fluoride phosphor may be mainly light in the blue region, and its peak wavelength may be, for example, within a wavelength range of 380 nm to 485 nm. The emission peak wavelength in the emission spectrum of the fluoride phosphor may be, for example, within a wavelength range of 610 nm to 650 nm. The half width in the emission spectrum of the fluoride phosphor may be, for example, 10 nm or less.

[0042] Method for producing fluoride phosphor The method for producing a fluoride fluorescent material includes a first step of preparing fluoride particles having a specific composition, and a second step of contacting the prepared fluoride particles with a treatment liquid containing complex ions including zirconium and fluoride ions to dispose a zirconium-containing fluorine compound on at least a portion of the surface of the fluoride particles. Here, the fluoride particles having the specific composition include element M including at least one element selected from the group consisting of Group 4 elements, Group 13 elements, and Group 14 elements, at least one element selected from the group consisting of alkali metals and ammonium ions, manganese, and fluorine atoms, and has a composition in which, when the total moles of the alkali metals and ammonium ions is 2, the number of moles of manganese is more than 0.2 and less than 0.8, the total moles of element M is more than 1, and the number of moles of fluorine atoms is more than 5 and less than 7.

[0043] By contacting fluoride particles having a predetermined composition with a treatment solution containing complex ions including zirconium and fluoride ions, a fluoride phosphor can be efficiently produced in which a fluoride compound containing zirconium is disposed on at least a portion of the surface of the fluoride particles. A light-emitting device equipped with the resulting fluoride phosphor and a wavelength conversion member containing a resin has improved reliability, for example, in high-temperature environments.

[0044] In the first step, fluoride particles having a predetermined composition are prepared. In the preparation step, the fluoride particles may be obtained or may be manufactured as desired. Details of the fluoride particles to be prepared are as described above.

[0045] The fluoride particles can be produced, for example, as follows: When the fluoride particles have a first composition, they can be produced by a production method including a step of mixing a solution a containing at least a first complex ion containing tetravalent manganese, a second complex ion containing at least one element selected from the group consisting of Group 4 elements and Group 14 elements, a fluorine ion, and hydrogen fluoride, with a solution b containing at least an alkali metal including at least potassium and hydrogen fluoride.

[0046] Alternatively, the fluoride phosphor having the first composition may be produced by a production method including a step of mixing a first solution containing at least a first complex ion containing tetravalent manganese and hydrogen fluoride, a second solution containing at least an alkali metal including at least potassium and hydrogen fluoride, and a third solution containing at least a second complex ion containing at least one element selected from the group consisting of Group 4 elements and Group 14 elements and a fluorine ion. For production methods of a fluoride phosphor having the first composition, see, for example, JP 2014-141684 A, JP 2015-143318 A, and JP 2015-188075 A.

[0047] Furthermore, when the fluoride particles have a second composition, the fluoride particles having the second composition can be produced by a method including, for example, preparing fluoride particles having a first composition, preparing fluoride particles containing Al, an alkali metal, and F, and subjecting a mixture containing the fluoride particles and the fluoride particles having the first composition to a first heat treatment in an inert gas atmosphere at a first heat treatment temperature of 600°C to 780°C. Here, the composition of the fluoride particles containing Al, an alkali metal, and F may be such that the ratio of the total number of moles of alkali metals to 1 mole of Al is 1 to 3, and the ratio of the number of moles of F is 4 to 6. Alternatively, the ratio of the total number of moles of alkali metals to 1 mole of Al may be 2 to 3, and the ratio of the number of moles of F to 5 to 6. For the method of producing the fluoride phosphor having the second composition, reference can be made to, for example, Japanese Patent Application Laid-Open Nos. 2010-254933 and 2022-099232.

[0048] In the second step, the prepared fluoride particles are brought into contact with a treatment liquid containing complex ions containing zirconium and fluoride ions, thereby disposing a zirconium-containing fluorine compound on at least a portion of the surface of the fluoride particles. When the treatment liquid containing complex ions containing zirconium and fluoride ions is brought into contact with the fluoride particles, a dissolution reaction occurs in a portion of the fluoride particles, producing at least one ion selected from the group consisting of alkali metal ions and ammonium ions that constitute the fluoride particles, and a complex ion containing element M and fluoride ions. It is believed that the generated at least one ion selected from the group consisting of alkali metal ions and ammonium ions reacts with the complex ion containing zirconium and fluoride ions, thereby disposing a zirconium-containing fluorine compound on the surface of the fluoride particles.

[0049] The treatment liquid contains a liquid medium and complex ions containing zirconium and fluoride ions. The liquid medium only needs to contain water, and may be essentially water if organic solvents, etc., described below, are excluded.

[0050] Complex ions containing zirconium and fluoride ions include [ZrF6] 2- , [ZrF7] 3- , [ZrF8] 4- , [ZrF5] - , [ZrF 10 ] 2- , [ZrF 12 ] 4- , [ZrF 13 ] 5- , [ZrF 14 ] 6- , [ZrF 31 ] 7- The treatment liquid is preferably [ZrF6] 2- The treatment solution may contain at least a complex ion having a composition represented by the formula: Counter cations of the complex ion containing zirconium and fluoride ions include hydrogen ions, ammonium ions, etc., and may contain at least hydrogen ions. The content of the complex ion containing zirconium and fluoride ions in the treatment solution may be, for example, 0.01 mol / L or more, preferably 0.02 mol / L or more, in terms of zirconium content. The content of the complex ion may be, for example, 1 mol / L or less, preferably 0.5 mol / L or less.

[0051] The treatment solution may further contain a boron oxoacid in addition to the complex ions containing zirconium and fluoride ions. Examples of boron oxoacids include orthoboric acid (H3BO3) and metaboric acid (HBO2). n), perboric acid (HBO3), hypoboric acid (H4B2O4), boronic acid (H3BO2), borinic acid (H3BO), etc. The boron oxoacid contained in the treatment solution may contain at least orthoboric acid. When the treatment solution contains a boron oxoacid, for example, hydrogen fluoride produced in conjunction with the production of a zirconium-containing fluorine compound can be removed as hydrofluoroboric acid (e.g., HBF4), thereby facilitating the production of a zirconium-containing fluorine compound. Specifically, when the treatment solution contains orthoboric acid, the following reaction can be considered to occur: In the following formula, A contains at least one selected from the group consisting of alkali metals and ammonium ions.

[0052] 2H2ZrF6+A2SiF6→2AZrF5+H2SiF6+2HF H3BO3+4HF→HBF4+3H2O

[0053] When the treatment solution contains a boron oxoacid, the content of the boron oxoacid in the treatment solution may be, for example, 0.01 mol / L or more, preferably 0.02 mol / L or 0.04 mol / L or more, in terms of boron content, and may be, for example, 0.4 mol / L or less, preferably 0.2 mol / L or less.

[0054] The treatment solution may further contain a reducing agent. By including a reducing agent, for example, tetravalent manganese ions that may be eluted from fluoride particles can be reduced, thereby suppressing coloration caused by tetravalent manganese ions. Examples of reducing agents include hydrogen peroxide and oxalic acid. The reducing agent may preferably contain at least hydrogen peroxide. Hydrogen peroxide has little effect on fluoride particles and can efficiently reduce tetravalent manganese ions. Furthermore, since it ultimately decomposes into harmless water and oxygen, it is easy to use in the production process and can reduce the environmental impact.

[0055] When the processing solution contains a reducing agent, the content of the reducing agent in the processing solution may be, for example, 0.1% by mass to 20% by mass, preferably 0.5% by mass or more or 5% by mass or less. The content of the reducing agent may be, for example, 0.02 mol / L to 4 mol / L, preferably 0.05 mol / L or more or 0.1 mol / L or more, and preferably 2 mol / L or less or 1 mol / L or less.

[0056] In the second step, the treatment liquid to be brought into contact with the fluoride particles may further contain an organic solvent. By including an organic solvent in the treatment liquid, the solubility of, for example, a zirconium-containing fluorine compound in the treatment liquid decreases, allowing the fluorine compound to be more efficiently arranged on the surface of the fluoride particles. This also promotes the production of a zirconium-containing fluorine compound. The organic solvent may be any organic solvent that is miscible with water, such as alcohol-based solvents having 3 or less carbon atoms, such as methanol, ethanol, propyl alcohol, and isopropyl alcohol; ketone-based solvents such as acetone and methyl ethyl ketone; and nitrile-based solvents such as acetonitrile. The organic solvent contained in the solution may preferably contain an alcohol having at least 3 or less carbon atoms.

[0057] When the treatment liquid in the second step contains an organic solvent, the content of the organic solvent in the treatment liquid containing the organic solvent may be, for example, 5% by volume or more, preferably 10% by volume or more, or 15% by volume or more. The content of the organic solvent may be, for example, 80% by volume or less, preferably 70% by volume or less, 60% by volume or less, or 55% by volume or less. Here, the volume of the treatment liquid containing the organic solvent is the sum of the volume of the treatment liquid without the organic solvent and the volume of the organic solvent added to the treatment liquid, and the change in volume due to mixing of water and the organic solvent is ignored.

[0058] The amount of the treatment liquid used to contact the fluoride particles in the second step may be, for example, 100% by mass or more and 3000% by mass or less, preferably 300% by mass or more or 500% by mass or more, and preferably 2500% by mass or less or 2000% by mass or less, in terms of mass ratio relative to the fluoride particles. When the mass ratio of the treatment liquid is within the above range, it tends to be possible to more uniformly arrange the zirconium-containing fluorine compound on the surface of the fluoride particles.

[0059] The contact between the fluoride particles and the treatment liquid can be carried out, for example, by mixing the fluoride particles with the treatment liquid. The contact may be carried out while stirring the treatment liquid containing the fluoride particles. The contact temperature between the fluoride particles and the treatment liquid may be, for example, 10°C or higher and 50°C or lower, and preferably 20°C or higher or 35°C or lower. The contact time may be, for example, 1 hour or higher and 40 hours or lower, and preferably 2 hours or higher or 30 hours or lower. The contact atmosphere may be either air or an inert gas atmosphere.

[0060] The method for producing a fluoride fluorescent material may further include, after the second step, a step of recovering the fluoride fluorescent material obtained in the second step by solid-liquid separation, a step of drying the fluoride fluorescent material after solid-liquid separation, etc.

[0061] Light-emitting device The light emitting device includes a wavelength converting member containing the fluoride phosphor and a resin, and a light source having an emission peak wavelength in the wavelength range of 380 nm to 485 nm. The light emitting device may further include other components as necessary.

[0062] An example of a light-emitting device will be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing an example of a light-emitting device according to this embodiment. This light-emitting device is an example of a surface-mounted light-emitting device. The light-emitting device 100 includes a light-emitting element 10, which is a light source that emits light having an emission peak wavelength on the short wavelength side of visible light (for example, in the range of 380 nm to 485 nm), and a molded body 40 on which the light-emitting element 10 is mounted. The molded body 40 includes a first lead 20 and a second lead 30, and is integrally molded from a thermoplastic resin or a thermosetting resin. The molded body 40 has a recess having a bottom surface and side surfaces corresponding to the substrate, and the light-emitting element 10 is mounted on the bottom surface of the recess. The light-emitting element 10 has a pair of positive and negative electrodes, which are electrically connected to the first lead 20 and the second lead 30 via wires 60. The light-emitting element 10 is covered with a wavelength conversion member 50. The wavelength conversion member 50 contains a phosphor 70 containing a fluoride phosphor that converts the wavelength of light from the light-emitting element 10. The phosphor 70 may contain the fluoride phosphor and a light-emitting material that emits light having an emission peak wavelength in a wavelength range different from that of the fluoride phosphor when excited by the excitation light from the light-emitting element 10 .

[0063] The wavelength conversion member may contain a resin and a phosphor. Examples of resins constituting the wavelength conversion member include silicone resin, epoxy resin, modified silicone resin, modified epoxy resin, and acrylic resin. For example, the refractive index of the silicone resin may be 1.35 or more and 1.55 or less, more preferably 1.38 or more and 1.43 or less. Silicone resins with refractive indices within these ranges have excellent light transmittance and are suitable for use as resins constituting wavelength conversion members. The refractive index of the silicone resin is measured after curing in accordance with JIS K7142:2008. In addition to the resin and phosphor, the wavelength conversion member may further contain a light diffusing material. The inclusion of a light diffusing material can reduce the directionality from the light-emitting element and increase the viewing angle. Examples of light diffusing materials include silicon oxide, titanium oxide, zinc oxide, zirconium oxide, and aluminum oxide.

[0064] The light-emitting element emits light having an emission peak wavelength in the wavelength range of 380 nm to 485 nm, which is the short wavelength region of visible light. The light-emitting element may be a light source that excites a fluoride phosphor. The light-emitting element preferably has an emission peak wavelength in the range of 380 nm to 480 nm, more preferably in the range of 410 nm to 480 nm, and even more preferably in the range of 430 nm to 480 nm. A semiconductor light-emitting element is preferably used as the light source. By using a semiconductor light-emitting element as the light source, a light-emitting device can be obtained that is highly efficient, has high output linearity relative to input, and is stable and resistant to mechanical shock. For example, a semiconductor light-emitting element using a nitride-based semiconductor can be used as the semiconductor light-emitting element. The half-width of the emission peak in the emission spectrum of the light-emitting element is preferably 30 nm or less.

[0065] The light emitting device is configured to include a fluoride phosphor. Details of the fluoride phosphor included in the light emitting device have been described above. The fluoride phosphor is contained, for example, in a wavelength conversion member that covers the light source. In a light emitting device in which the light source is covered with a wavelength conversion member containing a fluoride phosphor, a portion of the light emitted from the light source is absorbed by the fluoride phosphor and emitted as red light. By using a light source that emits light having an emission peak wavelength in the range of 380 nm to 485 nm, the emitted light can be used more effectively, the loss of light emitted from the light emitting device can be reduced, and a highly efficient light emitting device can be provided.

[0066] The light emitting device preferably further includes a light emitting material other than the fluoride phosphor in addition to the fluoride phosphor. The light emitting material other than the fluoride phosphor may be any material that absorbs light from a light source and converts the wavelength of the light into light of a different wavelength from that of the fluoride phosphor. The light emitting material may be contained in a wavelength conversion member, for example, in the same manner as the fluoride phosphor.

[0067] The luminescent material may have an emission peak wavelength in the wavelength range of 495 nm or more and 573 nm or less, and is preferably at least one selected from the group consisting of β - sialon phosphors, halosilicate phosphors, silicate phosphors, rare - earth aluminate phosphors, perovskite - type luminescent materials, and nitride phosphors. The β - sialon phosphor may have a composition represented by, for example, the following formula (IIa). The halosilicate phosphor may have a composition represented by, for example, the following formula (IIb). The silicate phosphor may have a composition represented by, for example, the following formula (IIc). The rare - earth aluminate phosphor may have a composition represented by the following formula (IId). The perovskite - type luminescent material may have a composition represented by, for example, the following formula (IIe). The nitride phosphor may have a composition represented by, for example, the following formula (IIf), (IIg), or (IIh). When the wavelength - converting member includes a β - sialon phosphor or a perovskite - type luminescent material as a luminescent material other than the fluoride phosphor, when the light - emitting device is used as a light source for a backlight, for example, a light - emitting device with a wider color - reproducibility range can be obtained. When the wavelength - converting member includes a halosilicate phosphor, a silicate phosphor, a rare - earth aluminate phosphor, or a nitride phosphor as a luminescent material other than the fluoride phosphor, when the light - emitting device is used as a light source for illumination, for example, a light - emitting device with higher color rendering properties or higher luminous efficiency can be obtained.

[0068] Si 6-x Al x O x N 8-x :Eu (IIa) (In formula (IIa), x is a number satisfying 0 < x ≤ 4.2.) (Ca,Sr,Ba)8MgSi4O 16 (F,Cl,Br)2:Eu (IIb) (Ba,Sr,Ca,Mg)2SiO4:Eu (IIc) (Y,Lu,Gd,Tb)3(Al,Ga)5O 12 :Ce (IId) CsPb(F,Cl,Br,I)3(IIe) (La,Y,Gd)3Si6N 11:Ce (IIf) (Sr,Ca)LiAl3N4:Eu(IIg) (Ca,Sr)AlSiN3:Eu(IIh)

[0069] The wavelength conversion member may further include at least one type of quantum dot in addition to the fluoride phosphor. The quantum dot may absorb light from a light source and convert it to light with a wavelength different from or similar to that of the fluoride phosphor. Examples of quantum dots include quantum dots having a perovskite structure with a composition such as (Cs,FA,MA)(Pb,Sn)(Cl,Br,I)3 (where FA stands for formamidinium and MA stands for methylammonium), quantum dots having a chalcopyrite structure with a composition such as (Ag,Cu,Au)(In,Ga)(S,Se,Te)2, semiconductor quantum dots such as (Cd,Zn)(Se,S), and InP-based semiconductor quantum dots. The wavelength conversion member may include at least one type selected from the group consisting of these. In the formula representing the composition of the quantum dot, multiple elements or cations separated by a comma (,) indicate that at least one of these multiple elements or cations is contained in the composition.

[0070] The invention according to the present disclosure may include, for example, the following aspects. [1] A fluoride phosphor comprising: fluoride particles; and a fluorine compound containing zirconium disposed on at least a portion of the surface of the fluoride particles; The fluoride particles are a fluoride phosphor having a composition comprising element M including at least one element selected from the group consisting of Group 4 elements, Group 13 elements, and Group 14 elements, at least one element selected from the group consisting of alkali metals and ammonium ions, manganese, and fluorine atoms, wherein, when the total number of moles of the alkali metals and ammonium ions is taken as 2, the number of moles of manganese is more than 0 and less than 0.2, the total number of moles of element M is more than 0.8 and less than 1, and the number of moles of fluorine atoms is more than 5 and less than 7.

[0071] [2] The fluoride particles are the fluoride phosphor according to [1] having a composition represented by the following formula (1). A c [M 1-b Mn b F d (1)

[0072] In formula (1), A contains at least one selected from the group consisting of Li, Na, K, Rb, Cs, and NH4. M contains at least one element selected from the group consisting of Group 4 elements, Group 13 elements, and Group 14 elements, and contains at least Si. b satisfies 0 < b < 0.2, and c is the absolute value of the charge of the [M + Mn 1-b Mn b F d ion, and d satisfies 5 < d < 7.

[0073] [3] The fluoride phosphor according to [1] or [2], wherein the content of the fluorine compound is 0.1% by mass or more and 10% by mass or less in terms of zirconium.

[0074] [4] The fluoride phosphor according to any one of [1] to [3], wherein the fluorine compound contains at least a compound having a composition represented by KZrF5.

[0075] [5] The fluoride phosphor according to any one of [1] to [4], wherein the alkali metal contains potassium, the ratio of the number of moles of potassium to the total number of moles of the alkali metal and ammonium ions is 0.9 or more and 1 or less, the element M contains silicon, and the ratio of the number of moles of silicon to the total number of moles of the element M is 0.9 or more and 1 or less.

[0076] [[ID=3[6] Prepare fluoride particles having a composition comprising at least one element M selected from the group consisting of Group 4 elements, Group 13 elements, and Group 14 elements, at least one selected from the group consisting of an alkali metal and an ammonium ion, manganese, and fluorine atoms, wherein when the total number of moles of the alkali metal and the ammonium ion is 2, the number of moles of manganese is more than 0 and less than 0.2, the total number of moles of element M is more than 0.8 and less than 1, and the number of moles of fluorine atoms is more than 5 and less than 7. Contact the prepared fluoride particles with a treatment liquid containing a complex ion containing zirconium and fluoride ions to dispose a fluorine compound containing zirconium on at least a part of the surface of the fluoride particles. A method for producing a fluoride phosphor comprising this.

[0077] [7] The fluoride particles have the composition represented by the following formula (1). The method for producing a fluoride phosphor according to [6]. A c [M 1-b Mn b F d (1)

[0078] In formula (1), A contains at least one selected from the group consisting of Li, Na, K, Rb, Cs, and NH4. M contains at least one element selected from the group consisting of Group 4 elements, Group 13 elements, and Group 14 elements, and contains at least Si. b satisfies 0 < b < 0.2, and c is the absolute value of the charge of the [M + Mn 1-b Mn b F d ion, and d satisfies 5 < d < 7.

[0079] [8] The treatment liquid further contains orthoboric acid. The method for producing a fluoride phosphor according to [6] or [7].

[0080] [9] The concentration of orthoboric acid in the treatment liquid is 0.04 mol / liter or more. The method for producing a fluoride phosphor according to [8].

[0081]

[10] The method for producing a fluoride fluorescent material according to any one of [6] to [9], wherein the treatment liquid further contains an organic solvent.

[0082]

[11] The method for producing a fluoride fluorescent material according to

[10] , wherein the organic solvent has a content of 15% by volume or more.

[0083]

[12] The method for producing a fluoride fluorescent material according to

[10] or

[11] , wherein the organic solvent contains an alcohol having 3 or less carbon atoms.

[0084]

[13] The method for producing a fluoride fluorescent material according to any one of [6] to

[12] , wherein the treatment liquid further contains a reducing agent.

[0085]

[14] A light emitting device comprising the fluoride phosphor according to any one of [1] to [4] and a light source having an emission peak wavelength in the range of 380 nm to 485 nm.

[0086]

[15] The light-emitting device according to

[14] , further comprising a light-emitting material having an emission peak wavelength in the range of 495 nm or more and 573 nm or less. [Example]

[0087] The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

[0088] Manufacturing Example 1 By a known method, the Mn content was 1.00 mass% and K2[Si 0.960 Mn 0.040 Fluoride particles, which are phosphors, having a theoretical composition represented by the formula [F6] were obtained.

[0089] Example 1 20 g of the fluoride particles produced in Production Example 1 were weighed out and placed in a 250 ml cylindrical plastic bottle. The mixture was a mixture of 60 g of 1.0 mol / L aqueous solution of fluorozirconic acid (H2ZrF6), 15 g of 1.0 mol / L aqueous solution of orthoboric acid (H3BO3), 30 g of 1.47 mol / L aqueous solution of hydrogen peroxide (H2O2), 45 g of pure water, and 38 ml (30 g) of ethanol. The mixture was stirred at room temperature for 5 hours using a mixer (product name: Mix Rotor MR-5, manufactured by AS ONE Corporation). The resulting precipitate was separated into solid and liquid, washed with ethanol, and dried at 90°C for 10 hours to produce the fluoride phosphor of Example 1.

[0090] Example 2 A fluoride fluorescent material of Example 2 was produced in the same manner as in Example 1, except that the amount of fluoride particles added was 40 g.

[0091] Example 3 A fluoride fluorescent material of Example 3 was produced in the same manner as in Example 1, except that the stirring time was set to 20 hours.

[0092] Example 4 The fluoride phosphor of Example 4 was prepared in the same manner as in Example 1, except that the amount of H2ZrF6 aqueous solution was 15 g, the amount of pure water was 90 g, and the amount of ethanol added was 152 ml (120 g).

[0093] Comparative Example 1 The fluoride particles obtained in Production Example 1 were used as the fluoride fluorescent material of Comparative Example 1.

[0094] evaluation The fluoride phosphors of Examples 1 to 4 and Comparative Example 1 obtained above were evaluated for relative luminance, manganese content, and zirconium content as follows.

[0095] Relative Luminance From the emission spectrum data measured for each fluoride phosphor, the emission luminance of the fluoride phosphors of Examples 1 to 4 was calculated as a relative luminance, with the emission luminance of the fluoride phosphor of Comparative Example 1 set at 100%. The results are shown in Table 1.

[0096] Manganese Content The manganese content of each fluoride phosphor was analyzed by inductively coupled plasma atomic emission spectroscopy (ICP-AES) to determine the content (Mn content; mass %) relative to the fluoride phosphor. The results are shown in Table 1.

[0097] Zirconium Content The zirconium content of each fluoride phosphor was analyzed by inductively coupled plasma atomic emission spectroscopy (ICP-AES) to determine the content (Zr content; mass %) relative to the fluoride phosphor. The results are shown in Table 1.

[0098] [Table 1]

[0099] The amount of Zr detected was below the measurement limit in the fluoride phosphor of Comparative Example 1. On the other hand, Zr was detected in the fluoride phosphors of Examples 1 to 4.

[0100] Scanning electron microscope observation SEM images were taken using a scanning electron microscope (SEM) for the fluoride phosphors obtained in Examples 1 and 3. The SEM image of the fluoride phosphor of Example 1 is shown in Figure 2A, and the SEM image of the fluoride phosphor of Example 3 is shown in Figure 2B.

[0101] X-ray diffraction spectrum The X-ray diffraction (XRD) spectra of the fluoride phosphors obtained in Examples 1 and 3 were measured using a horizontal sample multipurpose X-ray diffractometer (product name: Ultima IV, manufactured by Rigaku Corporation) with an X-ray source of CuKα radiation (λ = 0.15418 nm, tube voltage 40 kV, tube current 40 mA) under the following measurement conditions: angle: 10° to 70°, scan width: 0.02°, scan rate: 20° / min. The results are shown in Figure 3, along with the XRD spectrum of KZrF5.

[0102] Light-emitting device manufacturing example The light emitting device 100 shown in Fig. 1 was manufactured as follows. As the phosphor 70, the fluoride phosphor of Examples 1 and 2 or Comparative Example 1 and Si 5.81 Al 0.19 O 0.19 N 7.81 A β-sialon phosphor having a composition represented by the formula: β-sialon:Eu and having an emission peak wavelength near 540 nm was used. A fluoride phosphor, a β-sialon phosphor, and a silicone resin were mixed to obtain a resin composition such that the chromaticity coordinates in the CIE 1931 color system were approximately x 0.280 and y 0.270. Next, a molded body 40 having a recess was prepared. A light-emitting element 10 made of a gallium nitride-based compound semiconductor and having an emission peak wavelength of 451 nm was placed on the bottom of the recess on a first lead 20. The electrodes of the light-emitting element 10 were then connected to the first lead 20 and the second lead 30 with wires 60. A resin composition was then injected into the recess of the molded body 40 using a syringe to cover the light-emitting element 10. The resin composition was then cured to form a wavelength conversion member 50, thereby producing a light-emitting device 100.

[0103] Durability test 1 Each light-emitting device using the fluoride phosphor obtained in Examples 1 and 2 or Comparative Example 1 was stored for 500 hours in an environmental test chamber at a temperature of 85°C and a relative humidity of 85%, and durability test 1 was performed. The luminous flux maintenance factor (%) of the light-emitting device after durability test 1 was calculated, with the luminous flux of the light-emitting device before storage in the environmental test chamber being taken as 100%. A higher luminous flux maintenance factor (%) indicates better durability against high heat and humidity. The results are shown in Table 2.

[0104] Durability test 2 Each light-emitting device using the fluoride phosphor obtained in Examples 1 and 2 or Comparative Example 1 was subjected to durability test 2, in which the device was continuously lit at a current of 150 mA in an unhumidified environmental test chamber at 85°C for 500 hours. The x value of the chromaticity in the CIE 1931 color system of the light-emitting device before durability test 2 was set as the initial value, and the absolute value of the change in x value from the initial value in the CIE 1931 color system of the light-emitting device after durability test 2 was calculated as Δx. The Δx of the light-emitting device using the fluoride phosphor of Comparative Example 1 was set as the reference (100%), and the Δx obtained for each light-emitting device in the Examples was calculated as a relative Δx change rate (%) relative to the reference 100%. A lower relative Δx change rate (%) indicates a smaller change in chromaticity and thus higher durability. The results are shown in Table 2.

[0105] [Table 2]

[0106] Compared to the light emitting device using the fluoride phosphor of Comparative Example 1, the light emitting devices using the fluoride phosphors of Examples 1 and 2 had higher luminous flux maintenance in Durability Test 1 and lower Δx change rates in Durability Test 2, demonstrating superior durability. Furthermore, when comparing the light emitting device using the fluoride phosphor of Example 1 with the light emitting device using the fluoride phosphor of Example 2, the light emitting device using the fluoride phosphor of Example 1, which uses a fluoride phosphor with a higher Zr content, had a higher luminous flux maintenance in Durability Test 1 and lower Δx change rate in Durability Test 2 than the light emitting device using the fluoride phosphor of Example 2. This shows that light emitting devices using fluoride phosphors coated with a larger amount of a fluorine compound containing at least zirconium and fluorine exhibit higher durability. [Explanation of symbols]

[0107] 10: light emitting element, 20: first lead, 30: second lead, 40: molded body, 50: wavelength conversion member, 60: wire, 70: phosphor, 100: light emitting device.

Claims

1. A fluoride phosphor comprising: fluoride particles; and a fluorine compound containing zirconium disposed on at least a portion of the surface of the fluoride particles; The fluoride particles comprise an element M including at least one element selected from the group consisting of Group 4 elements, Group 13 elements, and Group 14 elements, at least one element selected from the group consisting of alkali metals and ammonium ions, manganese, and fluorine atoms, and the fluoride phosphor has a composition in which, when the total number of moles of the alkali metals and ammonium ions is taken as 2, the number of moles of manganese is more than 0 and less than 0.2, the total number of moles of element M is more than 0.8 and less than 1, and the number of moles of fluorine atoms is more than 5 and less than 7.

2. 2. The fluoride fluorescent material according to claim 1, wherein the fluoride particles have a composition represented by the following formula (1): A ｃ [M １－ｂ Mn ｂ F ｄ ] (1) (In formula (1), A is Li, Na, K, Rb, Cs, and NH ４ ＋ M contains at least one element selected from the group consisting of Group 4 elements, Group 13 elements, and Group 14 elements, and contains at least Si. b satisfies 0<b<0.2, and c satisfies [M １－ｂ Mn ｂ F ｄ ] is the absolute value of the charge of the ion, and d satisfies the relationship 5<d<7.

3. 2. The fluoride fluorescent material according to claim 1, wherein the content of the fluorine compound is 0.1% by mass or more and 10% by mass or less in terms of zirconium.

4. The fluorine compound is KZrF ５ 2. The fluoride fluorescent material according to claim 1, comprising at least a compound having a composition represented by the following formula:

5. 2. The fluoride particle according to claim 1, wherein the alkali metal contains potassium, and the ratio of the number of moles of potassium to the total number of moles of the alkali metal and ammonium ions is 0.9 or more and 1 or less, and the element M contains silicon, and the ratio of the number of moles of silicon to the total number of moles of the element M is 0.9 or more and 1 or less.

6. preparing fluoride particles having a composition including an element M including at least one element selected from the group consisting of Group 4 elements, Group 13 elements, and Group 14 elements, at least one element selected from the group consisting of alkali metals and ammonium ions, manganese, and fluorine atoms, wherein, when the total number of moles of the alkali metals and ammonium ions is 2, the number of moles of manganese is more than 0 and less than 0.2, the total number of moles of element M is more than 0.8 and less than 1, and the number of moles of fluorine atoms is more than 5 and less than 7; and bringing the prepared fluoride particles into contact with a treatment liquid containing complex ions containing zirconium and fluoride ions, thereby disposing a fluorine compound containing zirconium on at least a portion of the surface of the fluoride particles.

7. 7. The method for producing a fluoride fluorescent material according to claim 6, wherein the fluoride particles have a composition represented by the following formula (1): A ｃ [M １－ｂ Mn ｂ F ｄ ] (1) (In formula (1), A is Li, Na, K, Rb, Cs, and NH ４ ＋ M contains at least one element selected from the group consisting of Group 4 elements, Group 13 elements, and Group 14 elements, and contains at least Si. b satisfies 0<b<0.2, and c satisfies [M １－ｂ Mn ｂ F ｄ ] is the absolute value of the charge of the ion, and d satisfies the relationship 5<d<7.

8. The method for producing a fluoride fluorescent material according to claim 6 , wherein the treatment liquid further contains orthoboric acid.

9. 9. The method for producing a fluoride fluorescent material according to claim 8, wherein the concentration of orthoboric acid in the treatment solution is 0.04 mol / L or more.

10. The method for producing a fluoride fluorescent material according to claim 6 , wherein the treatment liquid further contains an organic solvent.

11. 11. The method for producing a fluoride fluorescent material according to claim 10, wherein the content of the organic solvent is 15% by volume or more.

12. The method for producing a fluoride fluorescent material according to claim 10 , wherein the organic solvent contains an alcohol having three or less carbon atoms.

13. The method for producing a fluoride fluorescent material according to claim 6 , wherein the treatment liquid further contains a reducing agent.

14. A light emitting device comprising: the fluoride phosphor according to claim 1; and a light source having an emission peak wavelength in the range of 380 nm to 485 nm.

15. 15. The light emitting device according to claim 14, further comprising a light emitting material having an emission peak wavelength in the range of 495 nm to 573 nm.

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