Oxide phosphor, and light-emitting device using the same

Abstract

To provide an oxide phosphor, and a light-emitting device.SOLUTION: An oxide phosphor has a composition represented by the formula (1). (Li1-qM1q)r(Mg1-sM2s)t(Ta1-u-vNbuM3v)wOx:Cry,M4z (1). (In the formula (1), M1 is at least one selected from a group composed of Na, K, Rb and Cs, M2 is at least one selected from a group composed of Zn, Ca, Sr and Ba, M3 is at least one selected from a group composed of P, V, Sb and Bi, M4 is at least one selected from a group composed of Ni, Ce, Eu, Fe, Mn, Nd, Tm, Ho, Er and Yb, and 0≤q≤0.5, 0.5≤r≤3.5, 0≤s≤0.5, 1.8≤t≤3.2, 0≤u≤1.0, 0≤v≤0.3, 0≤u+v≤1.0, 0.8≤w≤1.2, 5.1≤x≤6.9, 0.002≤y≤0.5 and 0≤z≤0.3 are satisfied.)SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to an oxide phosphor and a light-emitting device using the same. [Background technology]

[0002] Light-emitting devices having a light emission intensity in the wavelength range from red light to near-infrared light are desired for use in, for example, infrared cameras, infrared communications, light sources for plant growth and cultivation, vein authentication which is a type of biometric authentication, food component analysis equipment that non-destructively measures the sugar content of agricultural products such as fruits and vegetables or food, analytical equipment that non-destructively measures the presence of foreign matter in medicines, etc. Light-emitting devices that emit light in the wavelength range of visible light as well as in the wavelength range from red light to near-infrared light are also desired.

[0003] As such a light emitting device, there is a light emitting device in which a light emitting diode (LED) and a phosphor are combined. Furthermore, examples of phosphors that can be combined with light emitting devices include phosphors that have a relatively large emission spectrum and emission intensity in the wavelength range from red light to near infrared light (hereinafter, also referred to as "near infrared light emitting phosphors").

[0004] Patent Document 1 describes a near-infrared emitting phosphor having an emission peak wavelength in the range of 680 nm to 760 nm and a composition of, for example, CaYAlO4:Mn 4+ There is also a demand for near-infrared emitting phosphors having an emission spectrum with a wider full width at half maximum and an emission peak wavelength in a longer wavelength range, which are suitable for the above-mentioned applications. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Special Publication No. 2020-528486 Summary of the Invention [Problem to be solved by the invention]

[0006] An object of the present disclosure is to provide an oxide phosphor having an emission peak wavelength in the wavelength range from red light to near-infrared light and a wide full width at half maximum of the emission spectrum, and a light emitting device using the oxide phosphor. [Means for solving the problem]

[0007] The first aspect is an oxide phosphor having a composition represented by the following formula (1). (Li 1-q M 1 q ) r (Mg 1-s M 2 s ) t (Ta 1-u-v Nb u M 3 v ) w O x :Cr y ,M 4 z (1) (In the above formula (1), M 1 is at least one element selected from the group consisting of Na, K, Rb and Cs, and M 2 is at least one element selected from the group consisting of Zn, Ca, Sr and Ba, and M 3 is at least one element selected from the group consisting of P, V, Sb and Bi, and M 4 is at least one element selected from the group consisting of Ni, Ce, Eu, Fe, Mn, Nd, Tm, Ho, Er, and Yb, and q, r, s, t, u, v, w, x, y, and z satisfy 0≦q≦0.5, 0.5≦r≦3.5, 0≦s≦0.5, 1.8≦t≦3.2, 0≦u≦1.0, 0≦v≦0.3, 0≦u+v≦1.0, 0.8≦w≦1.2, 5.1≦x≦6.9, 0.002≦y≦0.5, and 0≦z≦0.3, respectively.

[0008] A second aspect is a light emitting device comprising the oxide phosphor and a light emitting element having an emission peak wavelength in the range of 365 nm to 650 nm and irradiating the oxide phosphor with excitation light. Effect of the Invention

[0009] According to the present disclosure, it is possible to provide an oxide phosphor having an emission peak wavelength in the wavelength range from red light to near-infrared light and a wide full width at half maximum of the emission spectrum, and a light emitting device using the same. [Brief description of the drawings]

[0010] [Figure 1] 1 is a schematic cross-sectional view showing an example of a first configuration example of a light emitting device. [Diagram 2] FIG. 4 is a schematic cross-sectional view showing another example of the first configuration example of the light emitting device. [Figure 3A] FIG. 4 is a schematic plan view showing a second configuration example of the light emitting device. [Figure 3B] FIG. 4 is a schematic cross-sectional view showing a second configuration example of the light emitting device. [Figure 4] FIG. 2 is a diagram showing the emission spectra of the oxide phosphors according to Examples 1 to 3. [Diagram 5] FIG. 2 is a diagram showing the emission spectra of the oxide phosphors according to Examples 4 to 6. [Figure 6] FIG. 1 is a diagram showing the emission spectra of the oxide phosphors according to Examples 7 to 9. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The oxide phosphor according to the present disclosure, a light-emitting device using the same, and a method for producing the oxide phosphor will be described below. However, the following embodiments are merely examples for embodying the technical concept of the present invention, and the present invention is not limited to the oxide phosphor and light-emitting device described below. Note that, for visible light, the relationship between color names and chromaticity coordinates, the relationship between the wavelength range of light and the color names of monochromatic light, etc., follow JIS Z8110.

[0012] A light-emitting device using a phosphor is required to emit light in an optimal wavelength range depending on the visual target and the usage situation. For example, in the medical field, it may be required to easily obtain information inside a living body. In a living body, light absorbers include water, hemoglobin, melanin, etc. For example, hemoglobin has a high absorption rate of light in the visible wavelength range of less than 650 nm, and a light-emitting device that emits light in the visible wavelength range has difficulty in transmitting light in the visible wavelength range inside a living body, making it difficult to obtain information inside the living body. If it is possible to irradiate light in a wavelength range in which the absorption and scattering of light in living tissue is small, it becomes easier to obtain information deep inside the living body. Therefore, there is a demand for a light-emitting device that can emit light in a wavelength range called the "biological window" through which light can easily penetrate inside the living body. As the "biological window," the wavelength range of about 650 nm to about 950 nm is sometimes called the "first biological window," the wavelength range of about 1000 nm to about 1350 nm is sometimes called the "second biological window," and the wavelength range of about 1500 nm to about 1800 nm is sometimes called the "third biological window." If it is possible to irradiate light in a wavelength range in which the absorption and scattering of light in tissues in a living body is small, it becomes easier to obtain information about the deep inside of the living body. For example, if it is possible to measure the increase or decrease in the oxygen concentration in blood in a living body by the increase or decrease in the absorption of light by hemoglobin that binds with oxygen, it becomes possible to easily obtain information about the inside of the living body by irradiating it with light from a light-emitting device. In addition, if information about the deep inside of the living body can be obtained by irradiating it with light from a phosphor and a light-emitting element rather than by irradiating it with X-rays or the like, it is possible to obtain information about the inside of the living body more safely. Therefore, the phosphor used in the light-emitting device may be required to have an emission peak wavelength in the wavelength range from red light to near-infrared light. The phosphor used in the light-emitting device may be one having a peak emission wavelength in the range of 680 nm to 1000 nm, or one having a peak emission wavelength in the range of 840 nm to 970 nm. Recently, there has been a demand for a light-emitting device that can more clearly visualize deep inside a living body and emits safe light in the wavelength range from red light to near-infrared light.Furthermore, in a light-emitting device including a light-emitting element and a phosphor, if it is possible to pass a high current and emit high-power light, detection capabilities can be improved, making it easier to obtain information inside the living body.

[0013] In the agricultural and food fields, there is a demand for non-destructive saccharometers that measure the sugar content of agricultural products and fruits and vegetables non-destructively, and measuring instruments that can perform non-destructive taste testing of rice (e.g., Taste Meter (registered trademark)). Near-infrared spectroscopy may be used as a method for non-destructively measuring the internal quality of fruits and vegetables, such as sugar content, acidity, ripeness, and internal damage, and the surface quality that appears on the surface of the fruit skin or the surface layer of the fruit skin near the surface, such as abnormal dryness. Near-infrared spectroscopy irradiates fruits and vegetables with light in the near-infrared wavelength range, receives the transmitted light that has passed through the fruits and vegetables, and the reflected light that has been reflected by the fruits and vegetables, and measures the quality of the fruits and vegetables based on the reduction in light intensity (light absorption). In such near-infrared spectroscopy analytical devices used in the food field, light sources such as tungsten lamps and xenon lamps are used. In the JIS K0134 General Rules for Near-Infrared Spectroscopic Analysis, it is stated that near-infrared light refers to a wavelength range of 700 nm or more and 2500 nm or less.

[0014] In addition, amid environmental changes such as climate change, it is desirable to provide a stable supply of vegetables and other plants and to increase plant production efficiency. Plant factories, which allow artificial management, are capable of steadily supplying safe vegetables to the market and are expected to be the next-generation industry. In such plant factories, light-emitting devices that irradiate light that can promote plant growth are required. Plant responses to light are divided into photosynthesis and photomorphogenesis. Photosynthesis is a reaction that uses light energy to decompose water, generate oxygen, and fix carbon dioxide into organic matter, and is a reaction necessary for plant growth. Photomorphogenesis is a morphological reaction that uses light as a signal to perform seed germination, differentiation (germination formation, leaf formation, etc.), movement (stoma opening and closing, chloroplast movement), light refraction, etc. It has been found that light in the wavelength range of 690 nm to 800 nm affects the photoreceptors of plants in photomorphogenesis reactions. For this reason, light-emitting devices used in plant factories and the like may be required to be capable of emitting light in a wavelength range that affects plant photoreceptors (chlorophyll a, chlorophyll b, carotenoids, phytochromes, cryptochromes, phototropins) and promotes plant growth.

[0015] With regard to the near-infrared light-emitting phosphors described above, there is room for improving the light-emitting characteristics as a phosphor so that light can be emitted suitable for the application when a light-emitting device is made using a light-emitting element such as a light-emitting diode (LED) or a laser diode (LD) that emits purple to blue light as an excitation light source.

[0016] In addition, there are cases where light emitting devices that emit light in the wavelength range of 365 nm to less than 700 nm, as well as light in the wavelength range from red light to near infrared light, are required. For example, there are cases where light emission in the wavelength range of visible light is required not only to obtain internal information about living organisms or fruits and vegetables, but also to improve the visibility of the target object.

[0017] The oxide phosphor has a composition represented by the following formula (1). (Li 1-q M 1 q ) r (Mg 1-s M 2s ) t (Ta 1-u-v Nb u M 3 v ) w O x :Cr y ,M 4 z (1) (In the above formula (1), M 1 is at least one element selected from the group consisting of Na, K, Rb and Cs, and M 2 is at least one element selected from the group consisting of Zn, Ca, Sr and Ba, and M 3 is at least one element selected from the group consisting of P, V, Sb and Bi, and M 4 is at least one element selected from the group consisting of Ni, Ce, Eu, Fe, Mn, Nd, Tm, Ho, Er, and Yb, and q, r, s, t, u, v, w, x, y, and z satisfy 0≦q≦0.5, 0.5≦r≦3.5, 0≦s≦0.5, 1.8≦t≦3.2, 0≦u≦1.0, 0≦v≦0.3, 0≦u+v≦1.0, 0.8≦w≦1.2, 5.1≦x≦6.9, 0.002≦y≦0.5, and 0≦z≦0.3, respectively.

[0018] In the oxide phosphor, when the variable y in the formula (1) expressing the molar ratio of the activator element Cr is within the range of 0.002 or more and 0.5 or less (0.002≦y≦0.5) in 1 mole of the oxide phosphor composition, the oxide phosphor has an emission peak wavelength in a desirable wavelength range from red light to near infrared light according to the intended use, and can obtain a relatively wide emission spectrum with a full width at half maximum. In the oxide phosphor, when the variable y in the formula (1) expressing the molar ratio of the activator element Cr is within the range of 0.002 or more and 0.5 or less (0.002≦y≦0.5) in 1 mole of the oxide phosphor composition, the variable y in the formula (1) may be within the range of 0.004 or more and 0.40 or less (0.004≦y≦0.40), within the range of 0.010 or more and 0.30 or less (0.005≦y≦0.30), within the range of 0.007 or more and 0.25 or less (0.007≦y≦0.25), within the range of 0.010 or more and 0.2 or less (0.010≦y≦0.2), or within the range of 0.0 It may be in the range of 15 or more and 0.15 or less (0.015≦y≦0.15), in the range of 0.020 or more and 0.10 or less (0.020≦y≦0.10), in the range of 0.020 or more and 0.090 or less (0.020≦y≦0.090), in the range of 0.020 or more and 0.080 or less (0.020≦y≦0.080), or in the range of 0.020 or more and 0.070 or less (0.020≦y≦0.070). In this specification, in the composition formula showing the composition of the phosphor containing the oxide phosphor, the part before the colon (:) shows the elements constituting the host crystal and their molar ratio, and the part after the colon (:) shows the activator element.

[0019] The oxide phosphor has a composition represented by the formula (1) and may optionally contain a first element M 1 is at least one element selected from the group consisting of Na, K, Rb and Sc, and may be two or more elements selected from the group consisting of Na, K, Rb and Sc. In 1 mol of the composition of the oxide phosphor represented by the formula (1), the first element M 1The molar ratio of is represented by the product of the variables q and r. In order for the oxide phosphor to emit light having an emission peak wavelength in the desired wavelength range from red light to near infrared light and a desired luminous efficiency with a wide full width at half maximum when irradiated with excitation light, the variable q in 1 mole of the composition represented by the above formula (1) is within the range of 0 to 0.5 (0≦q≦0.5), may be within the range of 0 to 0.3 (0≦q≦0.3), may be within the range of 0 to 0.2 (0≦q≦0.2), or may be within the range of 0 to 0.1 (0≦q≦0.1). In order for the oxide phosphor to emit light having an emission peak wavelength in the desired wavelength range from red light to near infrared light and a desired luminous efficiency with a wide full width at half maximum, the variable q in 1 mole of the composition represented by the above formula (1) is within the range of 0 to 0.5 (0≦q≦0.5), may be within the range of 0 to 0.3 (0≦q≦0.3), may be within the range of 0 to 0.2 (0≦q≦0.2), or may be within the range of 0 to 0.1 (0≦q≦0.1). 1 The first element M 1 In the case where the composition does not contain any of the elements, q may be substantially 0 (q=0) in the composition represented by the formula (1). In this specification, when the numerical value of a variable representing the molar ratio of an element in a composition is "substantially 0", it means that the element is not intentionally included. Specifically, when the numerical value of a variable representing the molar ratio of an element in a composition is substantially 0, it means that the numerical value of the variable representing the molar ratio of an element in a composition is substantially 0, which includes the case of 1000 ppm by mass or less, the case of 500 ppm by mass or less, and the case of 1 ppm by mass or more.

[0020] The oxide phosphor contains Li and a first element M in 1 mole of the composition represented by the formula (1). 1 The variable r representing the molar ratio of the total of the first element M is within the range of 0.5 to 3.5 (0.5≦r≦3.5). 1 When the variable r does not include Li, the variable r represents the molar ratio of Li. In the oxide phosphor, in 1 mole of the composition represented by the formula (1), the variable r may be in the range of 0.8 to 3.2 (0.8≦r≦3.2) or in the range of 1.0 to 3.0 (1.0≦r≦3.0). In the oxide phosphor, in 1 mole of the composition represented by the formula (1), if the variable r is in the range of 0.5 to 3.5 (0.5≦r≦3.5), the oxide phosphor emits light having a peak emission wavelength in the desired red to near-infrared wavelength range and a desired luminous efficiency with a wider full width at half maximum when irradiated with excitation light.

[0021] The oxide phosphor may include a second element M 2 is at least one element selected from the group consisting of Zn, Ca, Sr and Ba, and may be two or more elements selected from the group consisting of Zn, Ca, Sr and Ba. 2 In 1 mole of the composition of the oxide phosphor represented by the formula (1), the second element M 2 The molar ratio of is represented by the product of the variables s and t. In order to obtain light emission having an emission peak wavelength in a desired wavelength range depending on the purpose of use when irradiated with excitation light, the variable s in 1 mole of the composition represented by the above formula (1) is within the range of 0 to 0.5 (0≦s≦0.5), may be within the range of 0 to 0.3 (0≦s≦0.3), may be within the range of 0 to 0.2 (0≦s≦0.2), or may be within the range of 0 to 0.1 (0≦s≦0.1). In order to emit light having an emission peak wavelength in a desired wavelength range from red light to near-infrared light and a desired luminous efficiency with a wide full width at half maximum when irradiated with excitation light, the oxide phosphor contains the second element M 2 The second element M may not be included. 2 When no compound is contained, s may be substantially 0 (s=0) in the composition represented by formula (1).

[0022] The oxide phosphor contains Mg and a second element M in 1 mole of the composition represented by the formula (1). 2 The variable t representing the molar ratio of the total of the second element M is within the range of 1.8 to 3.2 (1.8≦r≦3.2). 2When the variable t does not include t, the variable t represents the molar ratio of Mg. In the oxide phosphor, in 1 mole of the composition represented by the formula (1), the variable t may be in the range of 1.9 to 3.1 (1.9≦t≦3.1), or in the range of 2.0 to 3.0 (2.0≦t≦3.0). In the oxide phosphor, in 1 mole of the composition represented by the formula (1), if the variable t is in the range of 1.8 to 3.2 (1.8≦t≦3.2), the oxide phosphor emits light having a desired emission peak wavelength in the wavelength range from red light to near infrared light and a desired emission efficiency with a wider full width at half maximum when irradiated with excitation light.

[0023] The oxide phosphor preferably contains at least one selected from the group consisting of Ta and Nb in the composition represented by the formula (1). The oxide phosphor may contain both Ta and Nb in the composition represented by the formula (1). By containing at least one selected from the group consisting of Ta and Nb in the oxide phosphor and the composition represented by the formula (1), the wavelength of the irradiated excitation light is converted, and light having an emission peak wavelength in a desired range depending on the purpose of use in the wavelength range from red light to near infrared light and a desired luminous efficiency with a wide full width at half maximum is emitted. In 1 mole of the composition of the oxide phosphor represented by the formula (1), the molar ratio of Nb is represented by the product of the variable u and the variable w. In 1 mole of the composition of the oxide phosphor represented by the formula (1), the variable u is in the range of 0 to 1.0 (0≦u≦1.0). When the variable u is 0 in the composition represented by the formula (1), Nb is not included in the oxide phosphor. In the composition represented by the formula (1), when the variable u is 1.0, the oxide phosphor contains Nb but does not contain Ta. In order to obtain light emission having an emission peak wavelength in a desired wavelength range depending on the intended use by irradiation with excitation light in 1 mol of the composition represented by the formula (1), the variable u of the oxide phosphor may be in the range of 0.1 to 0.9 (0.1≦u≦0.9), 0.2 to 0.8 (0.2≦u≦0.8), 0.3 to 0.7 (0.3≦u≦0.7), or 0.4 to 0.6 (0.4≦u≦0.6).

[0024] The oxide phosphor has a composition represented by the formula (1) that includes at least one selected from the group consisting of Ta and Nb, and the sum of variables u and v is within the range of 0 to 1.0 (0≦u+v≦1.0). The oxide phosphor has a composition represented by the formula (1) that includes at least one variable u and v is within the range of 0.1 to 0.9 (0≦u+v≦0.9), 0.2 to 0.8 (0.2≦u+v≦0.8), 0.3 to 0.7 (0.3≦u+v≦0.7), or 0.4 to 0.6 (0.4≦u+v≦0.6).

[0025] The oxide phosphor may include a third element M 3 is at least one element selected from the group consisting of P, V, Sb and Bi, and may be two or more elements selected from the group consisting of P, V, Sb and Bi. 3 In 1 mole of the composition of the oxide phosphor represented by the formula (1), the third element M 3 The molar ratio of is represented by the product of the variables v and w. In order for the oxide phosphor to emit light having an emission peak wavelength in the desired red to near-infrared wavelength range and a desired luminous efficiency with a wide full width at half maximum when irradiated with excitation light, the variable v is within the range of 0 to 0.3 (0≦v≦0.3), may be within the range of 0 to 0.2 (0≦v≦0.2), or may be within the range of 0 to 0.1 (0≦v≦0.1) in 1 mole of the composition represented by the above formula (1). In order for the oxide phosphor to emit light having an emission peak wavelength in the desired red to near-infrared wavelength range and a desired luminous efficiency with a wide full width at half maximum when irradiated with excitation light, the variable v is within the range of 0 to 0.3 (0≦v≦0.3), may be within the range of 0 to 0.2 (0≦v≦0.2), or may be within the range of 0 to 0.1 (0≦v≦0.1). 3 The third element M may not be included. 3 When no compound is contained, v may be substantially 0 (v=0) in the composition represented by formula (1).

[0026] The oxide phosphor contains Ta, Nb and a third element M in 1 mol of the composition represented by the formula (1). 3The variable w, which represents the molar ratio of the sum of Nb and the third element M, is within the range of 0.8 to 1.2 (0.8≦w≦1.2). When the variable w is within the range of 0.8 to 1.2 (0.8≦w≦1.2) in 1 mole of the composition represented by the formula (1), the oxide phosphor emits light having an emission peak wavelength in the desired wavelength range from red light to near infrared light and having a desired luminous efficiency with a wider full width at half maximum when irradiated with excitation light. The variable w may be within the range of 0.9 to 1.1 (0.9≦w≦1.1) in 1 mole of the composition represented by the formula (1) of the oxide phosphor, or may be 1 (w=1). When the variable w is within the range of 0.8 to 1.2 (0.8≦w≦1.2) in 1 mole of the composition represented by the formula (1), the oxide phosphor emits light having an emission peak wavelength in the desired wavelength range from red light to near infrared light and having a desired luminous efficiency with a wider full width at half maximum when irradiated with excitation light. 3 When the variable w does not include Ta, the variable w represents the molar ratio of Ta. In 1 mole of the composition represented by the formula (1) of the oxide phosphor, Ta and the third element M 3 When not included, the variable w represents the molar fraction of Nb.

[0027] The oxide phosphor may include a fourth element M 4 is at least one element selected from the group consisting of Ni, Ce, Eu, Fe, Mn, Nd, Tm, Ho, Er and Yb, and may be at least one element selected from the group consisting of Ni, Ce, Eu, Fe, Mn and Nd.

[0028] The oxide phosphor is an activator element together with Cr in 1 mole of the composition represented by the formula (1), and a fourth element M 4 The variable z representing the molar ratio of is within the range of 0 to 0.3 (0≦z≦0.3). The oxide phosphor may contain a fourth element M 4 The variable z representing the molar ratio of may be in the range of 0 to 0.2 (0≦z≦0.2), may be in the range of 0 to 0.1 (0≦z≦0.1), or may be 0.001 or more (0.001≦z). In order to emit light having an emission peak wavelength in the desired wavelength range from red light to near infrared light and having a desired luminous efficiency with a wide full width at half maximum when irradiated with excitation light in 1 mole of the composition represented by the above formula (1), the oxide phosphor contains a fourth element M 4The fourth element M may not be substantially contained. 4 In the case where no compound is contained, the variable z in the composition represented by formula (1) may be substantially 0 (z=0).

[0029] The oxide phosphor has a composition represented by the formula (1) of 1 mole, which contains a first element M 1 and the second element M 2 In the oxide phosphor, in 1 mole of the composition represented by the formula (1), the first element M 1 and the second element M 2 In the case where the first element M is not included, the variables q and r may each be substantially 0. In the formula (1), q and s may satisfy q=0 and s=0. In the oxide phosphor, in the composition represented by the formula (1), 1 and the second element M 2 When the compound does not contain the compound, when irradiated with excitation light, it emits light having an emission peak wavelength in the desired wavelength range from red light to near infrared light, and having a desired luminous efficiency with a wide full width at half maximum.

[0030] The oxide phosphor may have a composition represented by the following formula (1a), which is included in the composition represented by the above formula (1). Li r Mg t (Ta 1-u-v Nb u M 3 v ) w O x :Cr y ,M 4 z (1a) (In formula (1a), M 3 is at least one element selected from the group consisting of P, V, Sb and Bi, and M 4 is at least one element selected from the group consisting of Ni, Ce, Eu, Fe, Mn, Nd, Tm, Ho, Er, and Yb, and r, t, u, v, w, x, y, and z satisfy 0.5≦r≦3.5, 1.8≦t≦3.2, 0≦u≦1.0, 0≦v≦0.3, 0≦u+v≦1.0, 0.8≦w≦1.2, 5.1≦x≦6.9, 0.002≦y≦0.5, and 0≦z≦0.3.

[0031] The oxide phosphor has a composition represented by the formula (1) of 1 mole, which contains a first element M 1 , second element M 2 and the third element M 3 In the oxide phosphor, in 1 mole of the composition represented by the formula (1), the first element M 1 , second element M 2 and the third element M 3 When the formula (1) does not include the variable q, the variable s, and the variable v may each be substantially 0. In the formula (1), q, s, and v may respectively satisfy q=0, s=0, and v=0.

[0032] The oxide phosphor may have a composition represented by the following formula (1b), which is included in the composition represented by the above formula (1). Li r Mg t (Ta 1-u Nb u ) w O x :Cr y ,M 4 z (1b) (In formula (1b), M 4 is at least one element selected from the group consisting of Ni, Ce, Eu, Fe, Mn, Nd, Tm, Ho, Er, and Yb, and r, t, u, w, x, y, and z satisfy 0.5≦r≦3.5, 1.8≦t≦3.2, 0≦u≦1.0, 0.8≦w≦1.2, 5.1≦x≦6.9, 0.002≦y≦0.5, and 0≦z≦0.3.

[0033] The oxide phosphor contains Nb and a third element M in 1 mole of the composition represented by the formula (1). 3 may not be included, and the variable u may be substantially 0 (u=0) and the variable v may be substantially 0 (v=0).

[0034] The oxide phosphor contains Nb and a third element M in 1 mole of the composition represented by the formula (1). 3When the variable u is substantially 0 (u=0) and the variable v is substantially 0 (v=0), the variable y representing the molar ratio of Cr, which is an activator element, may be within the range of 0.01 to 0.2 (0.01≦y≦0.2) in order to obtain light emission having an emission peak wavelength in a desired wavelength range depending on the intended use by irradiation with excitation light. In the oxide phosphor, in 1 mole of the composition represented by the formula (1), the variable y may be within the range of 0.011 to 0.1 (0.011≦y≦0.1), 0.012 to 0.08 (0.012≦y≦0.08), 0.013 to 0.05 (0.013≦y≦0.05), or 0.013 to 0.04 (0.013≦y≦0.04).

[0035] The oxide phosphor contains Nb and a third element M in 1 mole of the composition represented by the formula (1). 3 does not contain the first element M 1 and the second element M 2 In addition, the variable q may be substantially 0 (q=0), the variable s may be substantially 0 (s=0), the variable u may be substantially 0 (u=0), and the variable v may be substantially 0 (v=0). 3 When the compound does not contain the compound, when irradiated with excitation light, it emits light having an emission peak wavelength in the desired wavelength range from red light to near infrared light, and having a desired luminous efficiency with a wide full width at half maximum.

[0036] The oxide phosphor may have a composition represented by the following formula (1c), which is included in the composition represented by the above formula (1). Li r Mg t Ta w O x :Cr y ,M 4 z (1c) (In formula (1c), M 4is at least one element selected from the group consisting of Ni, Ce, Eu, Fe, Mn, Nd, Tm, Ho, Er, and Yb, and r, t, w, x, y, and z satisfy 0.5≦r≦3.5, 1.8≦t≦3.2, 0.8≦w≦1.2, 5.1≦x≦6.9, 0.002≦y≦0.5, and 0≦z≦0.3.

[0037] In the oxide phosphor, in the formula (1c), y may be 0.01≦y≦0.2, 0.011≦y≦0.1, 0.012≦y≦0.08, 0.013≦y≦0.05, or 0.013≦y≦0.04. When the oxide phosphor in the formula (1b) is 0.01≦y≦0.2, the oxide phosphor emits light having an emission peak wavelength in the desired wavelength range from red light to near infrared light, a wider full width at half maximum, and a desired luminous efficiency, when irradiated with excitation light.

[0038] The oxide phosphor contains Ta and a third element M in 1 mole of the composition represented by the formula (1). 3 Alternatively, the variable u may be 1 (u=1.0) and the variable v may be substantially 0 (v=0). 3 When the compound does not contain the compound, when irradiated with excitation light, it emits light having an emission peak wavelength in the desired wavelength range from red light to near infrared light, and having a desired luminous efficiency with a wide full width at half maximum.

[0039] The oxide phosphor contains Ta and a third element M in 1 mole of the composition represented by the formula (1). 3When the variable u is 1 (u=1.0) and the variable v is substantially 0 (v=0), the variable y representing the molar ratio of Cr, which is an activator element, may be within the range of 0.01 to 0.2 (0.01≦y≦0.2) in order to emit light having a desired emission peak wavelength in the wavelength range from the desired red light to the near infrared light and a desired emission efficiency with a wider full width at half maximum by irradiation with excitation light. In the oxide phosphor, the variable y may be within the range of 0.015 to 0.15 (0.015≦y≦0.15), 0.02 to 0.1 (0.02≦y≦0.1), 0.02 to 0.08 (0.02≦y≦0.08), or 0.025 to 0.07 (0.025≦y≦0.07) in 1 mole of the composition represented by the formula (1).

[0040] The oxide phosphor contains Ta and a third element M in 1 mole of the composition represented by the formula (1). 3 does not contain the first element M 1 and the second element M 2 may not be included, and the variable q may be substantially 0 (q=0), the variable s may be substantially 0 (s=0), the variable u may be 1 (u=1.0), and the variable v may be substantially 0 (v=0).

[0041] The oxide phosphor may have a composition represented by the following formula (1d), which is included in the composition represented by the above formula (1). Li r Mg t Nb w O x :Cr y ,M 4 z (1d) (In formula (1d), M 4 is at least one element selected from the group consisting of Ni, Ce, Eu, Fe, Mn, Nd, Tm, Ho, Er, and Yb, and r, t, w, x, y, and z satisfy 0.5≦r≦3.5, 1.8≦t≦3.2, 0.8≦w≦1.2, 5.1≦x≦6.9, 0.002≦y≦0.5, and 0≦z≦0.3.

[0042] In the oxide phosphor, in the formula (1d), y may be 0.01≦y≦0.2, 0.015≦y≦0.15, 0.02≦y≦0.1, 0.02≦y≦0.08, or 0.025≦y≦0.07. When the oxide phosphor in the formula (1d) is 0.01≦y≦0.2, the oxide phosphor emits light having an emission peak wavelength in the desired wavelength range from red light to near infrared light, and having a desired luminous efficiency with a wider full width at half maximum when irradiated with excitation light.

[0043] The oxide phosphor preferably has an emission spectrum having an emission peak wavelength with a full width at half maximum in the range of 140 nm to 220 nm. The oxide phosphor preferably converts the wavelength of excitation light from an excitation light source such as a light-emitting element to emit light having an emission peak wavelength in a desired range from red light to near-infrared light in an emission spectrum, a wide full width at half maximum, and an emission intensity required for analysis, etc.

[0044] If light having a wide full width at half maximum emission spectrum can be irradiated in a wavelength range where information on the inside of a living body or information on agricultural products can be obtained non-destructively, information on the inside of a living body or on agricultural products can be easily obtained. In addition, it is desirable for the color of an object to be seen when irradiated with light (hereinafter also referred to as "color rendering") to have an emission spectrum in a wide wavelength range, and a wider full width at half maximum allows light with excellent color rendering to be emitted. For example, in a plant factory, even when emitting light in a wavelength range that affects the growth of plants, it may be required to emit light that does not destroy the spectral balance of light so that workers can work easily. The oxide phosphor may have an emission spectrum with a peak emission wavelength of 145 nm or more, or 150 nm or more. The oxide phosphor may have an emission spectrum with a peak emission wavelength of 215 nm or less, or 210 nm or less. The oxide phosphor may have an emission spectrum with a peak emission wavelength of 150 nm or more and 210 nm or less. In this specification, the full width at half maximum refers to a wavelength width that is 50% of the emission intensity at the emission peak wavelength showing the maximum emission intensity in an emission spectrum.

[0045] When the oxide phosphor contains at least Ta in 1 mol of the composition represented by the formula (1), the full width at half maximum of the emission spectrum having an emission peak wavelength may be in the range of 145 nm to 200 nm, or in the range of 150 nm to 180 nm. When the oxide phosphor has a composition represented by the formula (1c), the full width at half maximum of the emission spectrum having an emission peak wavelength may be in the range of 145 nm to 200 nm, or in the range of 150 nm to 180 nm. When the oxide phosphor contains at least Ta in 1 mol of the composition represented by the formula (1), the oxide phosphor contains Nb and a third element M 3 When the oxide phosphor contains at least Ta in 1 mol of the composition represented by the formula (1), Nb and the third element M 3 does not have to be included.

[0046] The oxide phosphor contains Ta and a third element M in 1 mol of the composition represented by the formula (1). 3 When the variable u is 1 (u=1.0) and the variable v is substantially 0 (v=0), the full width at half maximum of the emission spectrum having an emission peak wavelength may be in the range of 160 nm to 220 nm, or in the range of 170 nm to 210 nm. When the oxide phosphor has a composition represented by formula (1d), the full width at half maximum of the emission spectrum having an emission peak wavelength may be in the range of 160 nm to 220 nm, or in the range of 170 nm to 210 nm.

[0047] The oxide phosphor preferably has an emission peak wavelength in the range of 800 nm to 860 nm in the emission spectrum. The oxide phosphor converts the wavelength of the excitation light from an excitation light source such as a light-emitting element to emit light in the wavelength range from red light to near-infrared light. A light-emitting device equipped with an oxide phosphor that emits light in the wavelength range from red light to near-infrared light can replace a tungsten lamp or a xenon lamp. The oxide phosphor preferably has an emission spectrum that provides the emission intensity required for analysis in a wavelength range that is easy to obtain information on the inside of a living body or agricultural products. When the oxide phosphor has an emission peak wavelength in the range of 800 nm to 860 nm in the emission spectrum, an emission spectrum having the emission intensity required for analysis in a wavelength range that is easy to obtain information on the inside of a living body or information on agricultural products, foods, medicines, etc. in a non-destructive manner can be obtained. The oxide phosphor may have an emission peak wavelength in the range of 810 nm to 855 nm in the emission spectrum, or may have an emission peak wavelength in the range of 820 nm to 850 nm in the emission spectrum.

[0048] The light emitting device includes an oxide phosphor having a composition represented by the formula (1) and a light emitting element having an emission peak wavelength in the range of 365 nm to 650 nm and irradiating the oxide phosphor with excitation light. The oxide phosphor can be used as a member constituting a wavelength conversion member together with a translucent material.

[0049] A semiconductor element can be used as a light-emitting element that irradiates an oxide phosphor with excitation light. For example, a nitride semiconductor can be selected as a material for a light-emitting element that emits green and blue light. X Al Y Ga 1-X-Y N (0≦X≦1, 0≦Y≦1, X+Y≦1), etc. can be used. As a material for the light-emitting element that emits red light, for example, a gallium-aluminum-arsenide-based semiconductor or an aluminum-indium-gallium-phosphorus-based semiconductor can be selected. As the light-emitting element, for example, it is preferable to use an LED chip or an LD chip.

[0050] The light-emitting element may have an emission peak wavelength in the range of 365 nm to 650 nm, may have an emission peak wavelength in the range of 365 nm to 500 nm, may have an emission peak wavelength in the range of 370 nm to 490 nm, or may have an emission peak wavelength in the range of 375 nm to 480 nm. The light-emitting element may have an emission peak wavelength in the range of more than 500 nm to 650 nm, may have an emission peak wavelength in the range of 510 nm to 650 nm, or may have an emission peak wavelength in the range of 520 nm to 650 nm. By using the light-emitting element as an excitation light source for the oxide phosphor, it is possible to configure a light-emitting device that emits a mixed color light of a desired wavelength range of light from the light-emitting element and fluorescence from a phosphor containing the oxide phosphor. The full width at half maximum of the emission peak in the emission spectrum of the light-emitting element can be, for example, 30 nm or less. It is preferable to use a light-emitting element using, for example, a nitride-based semiconductor as the light-emitting element. By using a light emitting element using a nitride semiconductor as an excitation light source, it is possible to obtain a light emitting device that is highly efficient, has high output linearity with respect to input, and is stable and resistant to mechanical shock.

[0051] The light emitting device is essentially composed of a first phosphor containing the oxide phosphor described above, and may further contain a phosphor having a different composition. In addition to the first phosphor, the light emitting device is preferably provided with at least one phosphor selected from the group consisting of a second phosphor having an emission peak wavelength in the range of 455 nm or more and less than 495 nm, a third phosphor having an emission peak wavelength in the range of 495 nm or more and less than 610 nm, a fourth phosphor having an emission peak wavelength in the range of 610 nm or more and less than 700 nm, and a fifth phosphor having an emission peak wavelength in the range of 700 nm or more and 1550 nm or less in the emission spectrum of each phosphor. The light emitting device is provided with a light emitting element and a first phosphor containing the oxide phosphor described above, and by providing at least one phosphor selected from the group consisting of the second phosphor, the third phosphor, the fourth phosphor, and the fifth phosphor, the light emitting device can be used as a light source that emits light having an emission spectrum in a wavelength range including visible light to a part of near infrared light. The light emitting device has an emission spectrum similar to that of conventionally used tungsten lamps and xenon lamps, and can be used as a light source that can be made smaller than tungsten lamps and xenon lamps. The small light emitting device can be mounted on small mobile devices such as smartphones and smart watches, and the information obtained from within the body can be used for health management, etc. The light emitting device can be used, for example, in a reflectance spectroscopic measuring device or an illumination device that is capable of non-destructively measuring inside a living body, fruits and vegetables, etc. and that is required to produce light with excellent color rendering properties.

[0052] The second phosphor, which has a composition different from that of the first phosphor containing the above-mentioned oxide phosphor, preferably contains at least one phosphor selected from the group consisting of a phosphate phosphor having a composition represented by the following formula (2a), an aluminate phosphor having a composition represented by the following formula (2b), and an aluminate phosphor having a composition represented by the following formula (2c), and may contain two or more phosphors. (Ca, Sr, Ba, Mg) 10 (PO4)6(F,Cl,Br,I)2:Eu (2a) (Ba,Sr,Ca)MgAl 10 O 17:Eu (2b) Sr4Al 14 O 25 :Eu (2c) In this specification, when a plurality of elements are described in a composition formula separated by a comma (,), it means that at least one of these plurality of elements is contained in the composition.

[0053] The third phosphor preferably contains at least one phosphor selected from the group consisting of a silicate phosphor having a composition represented by the following formula (3a), an aluminate phosphor or gallate phosphor having a composition represented by the following formula (3b), a β-sialon phosphor having a composition represented by the following formula (3c), a cesium lead halide phosphor having a composition represented by the following formula (3d), and a nitride phosphor having a composition represented by the following formula (3e), and may contain two or more phosphors. When the third phosphor contains two or more phosphors, it is preferable that each of the two or more third phosphors has a different emission peak wavelength in the range of 495 nm or more and less than 610 nm. (Ca,Sr,Ba)8MgSi4O 16 (F,Cl,Br)2:Eu (3a) (Lu,Y,Gd,Tb)3(Al,Ga)5O 12 :Ce (3b) S 6-z Al z O z N 8-z :Eu (0 <z≦4.2) (3c) CsPb(F,Cl,Br)3(3d) (La,Y,Gd)3Si6N 11 :Ce (3e)

[0054] The fourth phosphor preferably contains at least one phosphor selected from the group consisting of a nitride phosphor having a composition represented by the following formula (4a), a fluorogermanate phosphor having a composition represented by the following formula (4b), an oxynitride phosphor having a composition represented by the following formula (4c), a fluoride phosphor having a composition represented by the following formula (4d), a fluoride phosphor having a composition represented by the following formula (4e), a nitride phosphor having a composition represented by the following formula (4f), and a nitride phosphor having a composition represented by the following formula (4g), and may contain two or more phosphors. When the fourth phosphor contains two or more phosphors, it is preferable that each of the two or more fourth phosphors is a phosphor having an emission peak wavelength in a different range within the range of 610 nm or more and less than 700 nm. (Sr,Ca)AlSiN3:Eu (4a) 3.5MgO·0.5MgF2·GeO2:Mn (4b) (Ca,Sr,Mg) k Si 12-(m+n) Al m+n O n N 16-n :Eu (4c) (In the formula (4c), k, m, and n satisfy 0 < k ≤ 2.0, 2.0 ≤ m ≤ 6.0, and 0 ≤ n ≤ 2.0.) A 1 c1 [M 6 1-b1 Mn 4+ b1 F d1 (4d) (In the formula (4d), A 1 is selected from the group consisting of at least one of K + , Li + , Na + , Rb + , Cs + and NH4 + , and among them, K + is preferable. M 6 contains at least one element selected from the group consisting of Group 4 elements and Group 14 elements, and among them, Si and Ge are preferable. b1 satisfies 0 < b1 < 0.2, and c1 is [M 6 1-b1 Mn4+ b1 F d1 is the absolute value of the charge of the ion, and d1 satisfies 5 < d1 < 7.) A 2 c2 [M 7 1-b2 Mn 4+ b2 F d2 (4e) (In the formula (4e), A 2 is at least one selected from the group consisting of K + , Li + , Na + , Rb + , Cs + and NH4 + , and among them, K + is preferred. M 7 includes group 13 elements, and may further include at least one element selected from the group consisting of group 4 elements and group 14 elements. The group 13 element is preferably Al, and the group 14 element is preferably Si. b2 satisfies 0 < b2 < 0.2, and c2 is [M 7 1-b2 Mn 4+ b2 F d2 is the absolute value of the charge of the ion, and d2 satisfies 5 < d2 < 7.) (Ba,Sr,Ca)2Si5N8:Eu (4f) (Sr,Ca)LiAl3N4:Eu (4g)

[0055] The fifth phosphor is a gallate phosphor having a composition represented by the following formula (5a), an aluminate phosphor having a composition represented by the following formula (5b), a gallate phosphor having a composition represented by the following formula (5c), an aluminate phosphor having a composition represented by the following formula (5d), and a phosphor having a composition represented by the following formula (5e) different in composition from the oxide phosphor, a phosphor having a composition represented by the following formula (5f) different in composition from the oxide phosphor, a phosphor having a composition represented by the following formula (5g) different in composition from the oxide phosphor, and a phosphor having a composition represented by the following formula (5h) different in composition from the oxide phosphor. The phosphor having a composition represented by the following formula (5i) which is different from the above oxide phosphor, a phosphor having a composition represented by the following formula (5j) which is different from the above oxide phosphor, a phosphor having a composition represented by the following formula (5k) which is different from the above oxide phosphor, a phosphor having a composition represented by the following formula (5l) which is different from the above oxide phosphor, a phosphor having a composition represented by the following formula (5m) which is different from the above oxide phosphor, and a phosphor having a composition represented by the following formula (5n) which is different from the above oxide phosphor, and may contain two or more phosphors.

[0056] Ga2O3:Cr (5a) Al2O3:Cr (5b) ZnGa2O4:Cr (5c) (Lu,Y,Gd,Tb)3(Al,Ga)5O 12 : Ce, Cr (5d)

[0057] M 8 g M 9 h M 10 i M 11 5O j :Cr e , M 12 f (5e) (In the formula (5e), ​​M 8 is at least one element selected from the group consisting of Li, Na, Ka, Rb and Cs, and M 9is at least one element selected from the group consisting of Mg, Ca, Sr, Ba, and Zn, and M 10 is at least one element selected from the group consisting of Ba, Al, Ga, In, and rare earth elements, and M 11 is at least one element selected from the group consisting of Si, Ti, Ge, Zr, Sn, Hf, and Pb, and M 12 is at least one element selected from the group consisting of Eu, Ce, Tb, Pr, Nd, Sm, Yb, Ho, Er, Tm, Ni, and Mn, and e, f, g, h, i, and j satisfy 0 < e ≤ 0.2, 0 ≤ f ≤ 0.1, f < e, 0.7 ≤ g ≤ 1.3, 1.5 ≤ h ≤ 2.5, 0.7 ≤ i ≤ 1.3, 12.9 ≤ j ≤ 15.1.)

[0058] (Mg 1-t1 M 13 t1 ) u1 (Ga 1-v1-x1-y1 M 14 v1 )2O w1 :Cr x1 ,M 15 y1 (5f) (In the formula (5f), M 13 is at least one element selected from the group consisting of Ca, Sr, Ba, Ni, and Zn, and M 14 is at least one element selected from the group consisting of B, Al, Sc, and In, and M 15 is at least one element selected from the group consisting of Eu, Ce, Tb, Pr, Nd, Sm, Yb, Ho, Er, Tm, and Mn, and t1, u1, v1, w1, x1, and y1 satisfy 0 ≤ t1 ≤ 0.8, 0.7 ≤ u1 ≤ 1.3, 0 ≤ v1 ≤ 0.8, 3.7 ≤ w1 ≤ 4.3, 0.02 < x1 ≤ 0.3, 0 ≤ y1 ≤ 0.2, y1 < x1.)

[0059] (Li 1-t2 M 16 t2 ) u2 (Ga 1-v2 M 17 v2 )5O w2 :Cr x2, Ni y2 , M 18 z2 (5g) (In the formula (5g), M 16 is at least one element selected from the group consisting of Na, K, Rb, and Cs, and M 17 is at least one element selected from the group consisting of B, Al, Sc, In, and rare earth elements, and M 18 is at least one element selected from the group consisting of Si, Ge, Sn, Ti, Zr, Hf, Bi, V, Nb, and Ta, and t2, u2, v2, w2, x2, y2, and z2 respectively satisfy 0 ≦ t2 ≦ 1.0, 0.7 ≦ u2 ≦ 1.6, 0 ≦ v2 < 1.0, 7.85 ≦ w2 ≦ 11.5, 0.05 ≦ x2 ≦ 1.2, 0 ≦ y2 ≦ 0.5, 0.25 < x2 + y2 ≦ 1.2, y2 < x2, 0 ≦ z2 ≦ 0.5.)

[0060] (Ga 1-u3 M 19 u3 )2(Ge 1-v3 M 20 v3 ) w3 O x3 :Cr y3 , M 21 z3 (5h) (In the formula (5h), M 19 is at least one element selected from the group consisting of Al, Sc, and In, and M 20 is at least one element selected from the group consisting of Si, Ti, Zr, Sn, and Hf, and M 21 is at least one element selected from the group consisting of Ni, Eu, Fe, Mn, Nd, Tm, Ho, Er, and Yb, and u3, v3, w3, x3, y3, and z3 respectively satisfy 0 ≦ u3 ≦ 1.0, 0 ≦ v3 ≦ 0.5, 1.0 ≦ w3 ≦ 3.0, 5 ≦ x3 ≦ 9, 0.005 ≦ y3 ≦ 1.0, 0 ≦ z3 ≦ 0.5.)

[0061] (Mg 1-s4 M 22 s4 )2(Al 1-t4 M 23 t4 )u4 (Ge 1-v4 M 24 v4 ) w4 O x4 :Cr y4 ,M 25 z4 (5i) (In the above formula (5i), M 22 is at least one element selected from the group consisting of Ca, Sr, Ba and Zn, and M 23 is at least one element selected from the group consisting of Ga, Sc, and In, and M 24 is at least one element selected from the group consisting of Si, Ti, Zr, Sn and Hf, and M 25 is at least one element selected from the group consisting of Ni, Ce, Eu, Fe, Mn, Nd, Tm, Ho, Er, and Yb, and s4, t4, u4, v4, w4, x4, y4, and z4 satisfy 0≦s4≦1.0, 0≦t4≦1.0, 1.5≦u4≦2.5, 0≦v4≦0.5, 3.0≦w4≦6.0, 11.0≦x4≦17.0, 0.005≦y4≦1.0, and 0≦z4≦0.5, respectively.

[0062] M 26 x5 (Al 1-y5 M 27 y5 ) z5 O x5+3 / 2z5 :Cr v5 ,M 28 w5 (5j) (In the above formula (5j), M 26 is at least one element selected from the group consisting of alkaline earth metal elements, M 27 is at least one element selected from the group consisting of Group 13 elements excluding Al, and M 28 is at least one element selected from the group consisting of Mn, Eu, Ce, Tb, Pr, Nd, Sm, Yb, Ho, Er, and Tm, and v5, w5, x5, y5, and z5 satisfy 0.004≦v5≦0.8, 0≦w5≦0.4, 0.004≦v5+w5≦0.8, 1.0≦x5≦4.0, 0≦y5≦0.7, and 4.0≦z5≦1.50, respectively.

[0063] M 29 t6 M 30 u6 (Ge 1-v6 M 31 v6 )6O w6 :Cr x6 ,M 32 y6 (5k) (In the formula (5k), M 29 is at least one element selected from the group consisting of Li, Na, K, Rb, and Cs, M 30 is at least one element selected from the group consisting of Ca, Sr, Mg, Ba, and Zn, M 31 is at least one element selected from the group consisting of Si, Ti, Zr, Sn, Hf, and Pb, M 32 is at least one element selected from the group consisting of Eu, Ce, Tb, Pr, Nd, Sm, Yb, Ho, Er, Tm, Ni, and Mn, and t6, u6, v6, w6, x6, and y6 satisfy 1.5 ≦ t6 ≦ 2.5, 0.7 ≦ u6 ≦ 1.3, 0 ≦ v6 ≦ 0.4, 12.9 ≦ w6 ≦ 15.1, 0 < x6 ≦ 0.2, 0 ≦ y6 ≦ 0.10, and y6 < x6, respectively.)

[0064] (Li 1-u7 M 33 u7 )4(Ge 1-v7 M 34 v7 ) w7 O x7 :Cr y7 ,M 35 z7 (5l) (In the formula (5l), M 33 is at least one element selected from the group consisting of Na, K, Rb, and Cs, M 34 is at least one element selected from the group consisting of Si, Ti, Zr, Sn, and Hf, M 35is at least one element selected from the group consisting of Ni, Eu, Fe, Mn, Nd, Tm, Ho, Er, and Yb, and u7, v7, w7, x7, y7, and z7 satisfy 0≦u7≦0.3, 0≦v7≦0.5, 3.5≦w7≦15, 9≦x7≦32, 0.005≦y7≦1.0, and 0≦z7≦0.5, respectively.

[0065] (Li 1-u8 M 36 u8 )2M 37 v8 M 38 w8 O x8 :Cr y8 ,M 39 z8 (5m) (In the above formula (5m), M 36 is at least one element selected from the group consisting of Na, K, Rb and Cs, and M 37 is at least one element selected from the group consisting of Mg, Ca, Sr, Ba and Zn, M 38 is at least one element selected from the group consisting of Si, Ge, Ti, Zr, Sn and Hf, and M 39 is at least one element selected from the group consisting of Ni, Eu, Fe, Mn, Nd, Tm, Ho, Er, and Yb, and u8, v8, w8, x8, y8, and z8 satisfy 0≦u8≦1.0, 0.8≦v8≦3.0, 1.8≦w8≦6, 5.4≦x8≦16, 0.005≦y8≦1.0, and 0≦z8≦0.5, respectively.

[0066] (Mg 1-p9 M 40 p9 ) q9 (Li 1-r9 M 41 r9 ) s9 (In 1-t9 M 42 t9 ) u9 (Ge 1-v9 M 43 v9 ) w9 O x9 :Cr y9 ,M44 z9 (5n) (In the above formula (5n), M 40 is at least one element selected from the group consisting of Ca, Sr, Ba and Zn, and M 41 is at least one element selected from the group consisting of Na, K, Rb and Cs, and M 42 is at least one element selected from the group consisting of Al, Ga, and Sc, and M 43 is at least one element selected from the group consisting of Si, Ti, Zr, Sn and Hf, and M 44 is at least one element selected from the group consisting of Ni, Ce, Eu, Fe, Mn, Nd, Tm, Ho, Er, and Yb, and p9, q9, r9, s9, t9, u9, v9, w9, x9, y9, and z9 satisfy 0≦p9≦1.0, 0.1≦q9≦0.9, 0≦r9≦1.0, 0.05≦s9≦0.45, 0≦t9≦0.5, 0.05≦u9≦0.45, 0≦v9≦1.0, 0.8≦w9≦1.3, 2.6≦x9≦3.6, 0.02≦y9≦0.5, 0≦z9≦0.3, and 0.9≦q9+s9+u9≦1.2, respectively.

[0067] 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 first configuration example of a light emitting device. Fig. 2 is a schematic cross-sectional view showing another example of the first configuration example of a light emitting device.

[0068] As shown in FIG. 1, the light emitting device 100 includes a molded body 40 having a recess, a light emitting element 10 serving as an excitation light source, and a wavelength conversion member 50 covering the light emitting element 10. The molded body 40 is formed by integrally molding a first lead 20, a second lead 30, and a resin part 42 containing a thermoplastic resin or a thermosetting resin. In the molded body 40, at least the first lead 20 and the second lead 30 form the bottom surface of the recess, and at least the resin part 42 forms the side surface of the recess. The light emitting element 10 is placed on the bottom surface of the recess of the molded body 40. 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, respectively. The light emitting element 10 is covered with a wavelength conversion member 50. The wavelength conversion member 50 includes a phosphor 70 that converts the wavelength of light emitted from the light emitting element 10, and a translucent material. The phosphor 70 essentially includes a first phosphor 71 including an oxide phosphor having a composition represented by the formula (1). The phosphor 70 may include a phosphor having an emission peak wavelength in a wavelength range different from the emission peak wavelength of the first phosphor 71 and having a composition different from that of the first phosphor 71. As shown in FIG. 2, the phosphor 70 preferably includes at least one phosphor selected from the group consisting of the second phosphor 72, the third phosphor 73, the fourth phosphor 74, and the fifth phosphor 75 described above, and may include two or more phosphors. The phosphor 70 essentially includes the first phosphor 71, and may include the second phosphor 72, the third phosphor 73, the fourth phosphor 74, and the fifth phosphor 75. The wavelength conversion member 50 also functions as a member for protecting the light emitting element 10, the wire 60, the phosphor 70, and the like from the external environment. The light emitting device 100 receives power from the outside via the first lead 20 and the second lead 30 and emits light.

[0069] 3A and 3B show a second configuration example of the light emitting device. FIG. 3A is a schematic plan view of the light emitting device 200. FIG. 3B is a schematic cross-sectional view of the light emitting device 200 shown in FIG. 3A along line III-III'. The light emitting device 200 includes a light emitting element 10 having an emission peak wavelength in the range of 365 nm to 650 nm, and a wavelength conversion member 51 including a wavelength conversion body 52 containing a first phosphor 71 that is excited by light from the light emitting element 10 and emits light, and a translucent body 53 disposed on the wavelength conversion body 52. ​​The light emitting element 10 is flip-chip mounted on the substrate 1 via bumps that are conductive members 61. The wavelength conversion body 52 of the wavelength conversion member 51 is disposed on the light emitting surface of the light emitting element 10 via an adhesive layer 80. The light emitting element 10 and the wavelength conversion member 51 have their sides covered by a covering member 90 that reflects light. The wavelength converter 52 essentially includes a first phosphor 71 that is excited by light from the light emitting element 10 and includes an oxide phosphor having a composition represented by the formula (1). The wavelength converter 52 may include at least one selected from the group consisting of a second phosphor, a third phosphor, a fourth phosphor, and a fifth phosphor. The light emitting element 10 can receive power from the outside of the light emitting device 200 via wiring and a conductive member 61 formed on the substrate 1 to cause the light emitting device 200 to emit light. The light emitting device 200 may include a semiconductor element 11 such as a protective element for protecting the light emitting element 10 from destruction due to application of an excessive voltage. The semiconductor element 11 may be mounted on the substrate 1 via the conductive member 61. The covering member 90 is disposed so as to cover, for example, the semiconductor element 11. Each member used in the light emitting device will be described below. For details, the disclosure of JP 2014-112635 A may be referred to.

[0070] The light-transmitting material constituting the wavelength conversion body together with the phosphor may be at least one selected from the group consisting of resin, glass, and inorganic material. The resin may be at least one selected from the group consisting of silicone resin, epoxy resin, phenol resin, polycarbonate resin, acrylic resin, and modified resins thereof. Silicone resin and modified silicone resin are preferable in terms of excellent heat resistance and light resistance. In addition to the phosphor and the light-transmitting material, the wavelength conversion member may contain a filler, a colorant, and a light diffusing material as necessary. Examples of the filler include silicon oxide, barium titanate, titanium oxide, and aluminum oxide.

[0071] The light-transmitting body can be a plate-shaped body made of a light-transmitting material such as glass or resin. Examples of glass include borosilicate glass and quartz glass. Examples of resin include silicone resin and epoxy resin. When the wavelength conversion member includes a substrate, the substrate is preferably made of an insulating material that is difficult to transmit light from the light-emitting element and external light. Examples of materials for the substrate include ceramics such as aluminum oxide and aluminum nitride, and resins such as phenol resin, epoxy resin, polyimide resin, bismaleimide triazine resin (BT resin), and polyphthalamide (PPA) resin. When an adhesive layer is interposed between the light-emitting element and the wavelength conversion member, the adhesive constituting the adhesive layer is preferably made of a material that can optically connect the light-emitting element and the wavelength conversion member. The material constituting the adhesive layer is preferably at least one resin selected from the group consisting of epoxy resin, silicone resin, phenol resin, and polyimide resin. The light-transmitting body does not have to be disposed in the wavelength conversion member.

[0072] Examples of the semiconductor element provided in the light emitting device as required include a transistor for controlling the light emitting element and a protective element for suppressing the destruction or performance deterioration of the light emitting element due to the application of an excessive voltage. An example of the protective element is a Zener diode. When the light emitting device includes a covering member, it is preferable to use an insulating material as the material of the covering member. More specifically, examples of the insulating material include phenol resin, epoxy resin, bismaleimide triazine resin (BT resin), polyphthalamide (PPA) resin, and silicone resin. A colorant, a phosphor, and a filler may be added to the covering member as required. The light emitting device may use bumps as the conductive member. The bump material may be Au or its alloy, and other conductive members may be eutectic solder (Au-Sn), Pb-Sn, lead-free solder, and the like.

[0073] An example of a method for manufacturing the light emitting device of the first configuration example will be described. For details, the disclosure of JP 2010-062272 A can be referred to. The method for manufacturing the light emitting device preferably includes a molded body preparation step, a light emitting element arrangement step, a wavelength conversion member forming composition arrangement step, and a resin package formation step. When an aggregate molded body having a plurality of recesses is used as the molded body, a singulation step of separating the resin packages of each unit area may be included after the resin package formation step.

[0074] In the step of preparing a molded body, a plurality of leads are integrally molded using a thermosetting resin or a thermoplastic resin to prepare a molded body having a recess having a side surface and a bottom surface. The molded body may be a molded body made of an aggregate base including a plurality of recesses.

[0075] In the step of arranging the light-emitting element, the light-emitting element is arranged on the bottom surface of the recess of the molded body, and the positive and negative electrodes of the light-emitting element are connected to the first lead and the second lead by wires.

[0076] In the step of placing the composition for forming a wavelength conversion member, the composition for forming a wavelength conversion member is placed in the recess of the molded body.

[0077] In the resin package molding step, the composition for forming the wavelength conversion member arranged in the recess of the molded body is cured to form a resin package, and a light emitting device is manufactured. When a molded body made of an aggregate base having a plurality of recesses is used, after the resin package forming step, the aggregate base having a plurality of recesses is separated into each resin package of each unit area in the singulation step, and individual light emitting devices are manufactured. In this manner, the light emitting device shown in FIG. 1 or FIG. 2 can be manufactured.

[0078] An example of a method for manufacturing the light emitting device of the second configuration example will be described. For details, refer to the disclosure of, for example, JP 2014-112635 A or JP 2017-117912 A. The method for manufacturing the light emitting device preferably includes a step of arranging the light emitting element, a step of arranging the semiconductor element as necessary, a step of forming a wavelength conversion member including a wavelength converter, a step of bonding the light emitting element and the wavelength conversion member, and a step of forming a covering member.

[0079] For example, in the step of arranging the light-emitting element, the light-emitting element is arranged on the substrate. The light-emitting element and the semiconductor element are, for example, flip-chip mounted on the substrate. Next, in the step of forming the wavelength conversion member including the wavelength converter, the wavelength conversion member may be obtained by forming a plate-shaped, sheet-shaped or layer-shaped wavelength conversion member on one side of the light-transmitting body by a printing method, an adhesion method, a compression molding method or an electrodeposition method. For example, the printing method can print a composition for wavelength conversion body containing a phosphor and a resin serving as a binder or a solvent on one side of the light-transmitting body to form a wavelength conversion member including a wavelength conversion body. Next, in the adhesion step of the light-emitting element and the wavelength conversion member, the wavelength conversion member is opposed to the light-emitting surface of the light-emitting element, and the wavelength conversion member is bonded to the light-emitting element by an adhesive layer. Next, in the step of forming the covering member, the side surfaces of the light-emitting element and the wavelength conversion member are covered with the composition for covering member. This covering member is for reflecting the light emitted from the light-emitting element, and when the light-emitting device also includes a semiconductor element, it is preferable to form the semiconductor element so that it is embedded in the covering member. In the above manner, the light-emitting device shown in FIG. 3A and FIG. 3B can be manufactured.

[0080] The method for producing an oxide phosphor having a composition represented by the formula (1) includes preparing at least a first compound containing Li, a second compound containing Mg, a third compound containing Ta and / or a fourth compound containing Nb, and a fifth compound containing Cr, and, if necessary, adding at least one first element M selected from the group consisting of Na, K, Rb, and Cs. 1 and optionally at least one second element M selected from the group consisting of Zn, Ca, Sr and Ba. 2 and at least one third element M selected from the group consisting of P, V, Sb and Bi. 3 and optionally at least one fourth element M selected from the group consisting of Ni, Ce, Eu, Fe, Mn, Nd, Tm, Ho, Er and Yb. 4 and a ninth compound containing: preparing a raw material mixture in which each compound is adjusted and mixed so that the molar ratio of each element in 1 mole of the composition of the oxide phosphor satisfies the composition represented by the formula (1); and heat-treating the raw material mixture in an oxygen-containing atmosphere at a temperature in the range of 1300°C to 1600°C to obtain an oxide phosphor. It is preferable that at least one selected from the group consisting of the first compound, the second compound, the third compound, the fourth compound, the fifth compound, the seventh compound, the eighth compound, and the ninth compound is an oxide. It is preferable that the obtained oxide phosphor has a molar ratio of each element of the oxide phosphor in 1 mole of the composition of the oxide phosphor in the same range as the charged composition for obtaining the raw material mixture.

[0081] The raw materials for producing the oxide phosphor are a first compound containing Li, a second compound containing Mg, a third compound containing Ta, a fourth compound containing Nb, a fifth compound containing Cr, and the first element M, which is included as necessary. 1 A sixth compound containing, as necessary, a second element M 2 A seventh compound containing a third element M 3 and an eighth compound containing a fourth element M 4The ninth compound including the above may be an oxide, a carbonate, a chloride, or a hydrate thereof. At least one compound selected from the group consisting of the first compound, the second compound, the third compound, the fourth compound, the fifth compound, the seventh compound, the eighth compound, and the ninth compound is an oxide, and two or more of the compounds may be oxides. The first compound, the second compound, the third compound, the fourth compound, the fifth compound, the seventh compound, the eighth compound, and the ninth compound are preferably in the form of powder.

[0082] Examples of the first compound containing Li include Li2O, Li2CO3, and LiCl. Examples of the second compound containing Mg include MgO, MgCO3, and MgCl2. Examples of the third compound containing Ta include Ta2O5 and TaCl5. Examples of the fourth compound containing Nb include Nb2O5 and NbCl5. Examples of the fifth compound containing Cr include Cr2O3, Cr2(CO3)3, and CrCl3. The first element M 1 Examples of the sixth compound containing the second element M include Na2O, NaCl, Na2CO3, K2O, KCl, K2CO3, Rb2O, RbCl, Rb2CO3, Cs2O, CsCl, and Cs2CO3. 2 Examples of the seventh compound containing the third element M include ZnO, ZnCO3, ZnCl2, CaO, CaCO3, CaCl2, SrO, SrCO3, SrCl2, BaO, BaCO3, and BaCl2. 3 Examples of the eighth compound containing the fourth element M include PCl3, V2O5, VCl3, Sb2O3, Bi2O3, and BiCl3. 4 Examples of the ninth compound include NiO, NiCl2, CeO2, CeCl3, Ce2(CO3)3, Eu2O3, EuCl3, Fe2O3, Fe3O4, FeCl2, FeCl3, FeCO3, Fe2(CO3)3, MnO, MnO2, Mn2O3, Mn3O4, Nd2(CO3)3, Nd2O3, NdCl3, Tm2O3, TmCl3, Ho2O3, HoCl3, Er2O3, ErCl3, Yb2O3, and YbCl3. The first, second, third, fourth, fifth, seventh, eighth, and ninth compounds may be hydrates.

[0083] The raw material mixture is preferably prepared by adjusting and mixing each raw material so as to have a composition represented by the following formula (1). It is preferable that the oxide phosphor obtained by the production method has a composition in which each element of the oxide phosphor per mole of the oxide phosphor has the same composition as that represented by the following formula (1) for obtaining the raw material mixture. (Li 1-q M 1 q ) r (Mg 1-s M 2 s ) t (Ta 1-u-v Nb u M 3 v ) w O x :Cr y ,M 4 z (1) (In the above formula (1), M 1 is at least one element selected from the group consisting of Na, K, Rb and Cs, and M 2 is at least one element selected from the group consisting of Zn, Ca, Sr and Ba, and M 3 is at least one element selected from the group consisting of P, V, Sb and Bi, and M 4 is at least one element selected from the group consisting of Ni, Ce, Eu, Fe, Mn, Nd, Tm, Ho, Er, and Yb, and q, r, s, t, u, v, w, x, y, and z satisfy 0≦q≦0.5, 0.5≦r≦3.5, 0≦s≦0.5, 1.8≦t≦3.2, 0≦u≦1.0, 0≦v≦0.3, 0≦u+v≦1.0, 0.8≦w≦1.2, 5.1≦x≦6.9, 0.002≦y≦0.5, and 0≦z≦0.3, respectively.

[0084] The raw material mixture may be prepared by mixing the compounds so as to have a composition represented by formula (1a), which is included in the composition represented by formula (1), by mixing the compounds so as to have a composition represented by formula (1b), by mixing the compounds so as to have a composition represented by formula (1c), or by mixing the compounds so as to have a composition represented by formula (1d).

[0085] The first compound, the second compound, the third compound and / or the fourth compound, and the fifth compound are weighed so that the elements contained in each compound of the raw material satisfy the above-mentioned composition, and the sixth compound, the seventh compound, the eighth compound, and the ninth compound are weighed as necessary, and the weighed compounds are mixed in a wet or dry manner to obtain a raw material mixture. The weighed compounds may be mixed using a mixer. As the mixer, in addition to a ball mill that is commonly used industrially, a vibration mill, a roll mill, a jet mill, and the like can be used.

[0086] The raw material mixture may contain a flux. When the raw material mixture contains a flux, the reaction between the raw materials is promoted, and furthermore, the solid-phase reaction proceeds more uniformly, so that a phosphor having a large particle size and excellent luminescence characteristics can be obtained. When the temperature of the heat treatment for obtaining the phosphor is approximately the same as the temperature at which the liquid phase of the compound used as the flux is generated, the flux promotes the reaction between the raw materials. As the flux, boric acid, a borate containing at least one element selected from the group consisting of an alkaline earth metal element and an alkali metal element, or a halide containing at least one element selected from the group consisting of an alkaline earth metal element and an alkali metal element can be used. As the flux, among the halides, a fluoride can be used. As the flux, for example, boric acid (H3BO3), lithium fluoride (LiF), etc. can be used. When the flux contains an element contained in the composition represented by the formula (1), the flux can also be used as a part of the molar ratio of the element contained in the composition represented by the formula (1).

[0087] The raw material mixture can be placed in a crucible or boat made of a material such as graphite or other carbon, boron nitride (BN), alumina (Al2O3), tungsten (W), or molybdenum (Mo), and then heat-treated in a furnace.

[0088] The heat treatment of the raw material mixture is carried out in an atmosphere containing oxygen. The oxygen content in the atmosphere is not particularly limited. The oxygen content in the oxygen-containing atmosphere is preferably 5% by volume or more, more preferably 10% by volume or more, and even more preferably 15% by volume or more. The heat treatment is preferably carried out in an air atmosphere (oxygen content of 20% by volume or more). If the oxygen-free atmosphere has an oxygen content of less than 1% by volume, an oxide phosphor having the desired composition may not be obtained.

[0089] The temperature for heat-treating the raw material mixture is in the range of 1300°C to 1600°C, preferably in the range of 1350°C to 1550°C, more preferably in the range of 1400°C to 1500°C. If the heat-treating temperature is in the range of 1300°C to 1600°C, decomposition due to heat is suppressed, and a phosphor having a target composition and a stable crystal structure is obtained. In consideration of the reactivity of Ta or Nb contained in the raw material mixture, the temperature for heat-treating the raw material mixture is preferably 1300°C or higher. In consideration of the volatility of Li contained in the raw material mixture, in order to obtain an oxide phosphor having a target composition, the temperature for heat-treating the raw material mixture is preferably 1500°C or lower.

[0090] In the heat treatment, a holding time may be set at a predetermined temperature. The holding time may be, for example, 0.5 hours to 48 hours, 1 hour to 40 hours, 2 hours to 30 hours, 3 hours to 20 hours, or 5 hours to 10 hours. By setting the holding time to 0.5 hours to 48 hours, crystal growth can be promoted.

[0091] The pressure of the heat treatment atmosphere may be standard atmospheric pressure (0.101 MPa, air atmosphere), 0.101 MPa or more, or a pressurized atmosphere of 0.11 MPa to 200 MPa. When the heat treatment temperature is high, the heat-treated product obtained by the heat treatment is likely to have a decomposition of its crystal structure, but when the heat treatment is performed in a pressurized atmosphere, the decomposition of the crystal structure can be suppressed.

[0092] The heat treatment time can be appropriately selected depending on the heat treatment temperature and the pressure of the atmosphere during the heat treatment, and is preferably 0.5 hours or more and 20 hours or less. Even when two or more stages of heat treatment are performed, it is preferable that the heat treatment time for each stage is 0.5 hours or more and 20 hours or less. If the heat treatment time is 0.5 hours or more and 20 hours or less, decomposition of the heat-treated product obtained is suppressed, and a phosphor having a stable crystal structure and a desired emission intensity can be obtained. In addition, the production cost can be reduced and the manufacturing time can be relatively short. The heat treatment time is more preferably 1 hour or more and 10 hours or less, and even more preferably 1.5 hours or more and 9 hours or less.

[0093] The heat-treated product obtained by the heat treatment may be subjected to post-treatment such as pulverization, dispersion, solid-liquid separation, drying, etc. Solid-liquid separation can be carried out by an industrially commonly used method such as filtration, suction filtration, pressure filtration, centrifugation, decantation, etc. Drying can be carried out by an industrially commonly used device such as a vacuum dryer, a hot air heating dryer, a conical dryer, a rotary evaporator, etc. EXAMPLES

[0094] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0095] Oxide phosphor Example 1 The raw materials were weighed out so that the first compound Li2CO3 was 3.33g, the second compound MgO was 2.42g, the third compound Ta2O5 was 6.63g, and the fifth compound Cr2O3 was 0.03g. The molar ratio of each element in 1 mole of the resulting oxide phosphor was Li3Mg2TaO6:Cr 0.013The raw materials were weighed out so that the amount of the raw materials was 100%. The raw materials were mixed for 10 minutes using an agate mortar and an agate pestle to obtain a raw material mixture. The obtained raw material mixture was placed in an alumina crucible and heat-treated for 8 hours in an air atmosphere (oxygen 20% by volume) at 1400°C and standard pressure (0.101 MPa). After the heat treatment, the obtained heat-treated product was crushed to obtain an oxide phosphor of Example 1 having a composition shown in Table 1, which is the molar ratio of the charged composition. In the composition of the oxide phosphor of Example 1 shown in Table 1, the variable q in the formula (1) is 0 (q=0), the variable r is 3 (r=3), the variable s is 0 (s=0), the variable t is 2 (t=2), the variable u is 0 (u=0), the variable v is 0 (v=0), the variable w is 1 (w=1), the variable x is 6 (x=6), the variable y is 0.013 (y=0.013), and the variable z is 0 (z=0). In the composition formula, there may be elements without a numerical value, and the molar ratio of the elements without a numerical value is 1.

[0096] Example 2 The raw materials were weighed out so that the first compound Li2CO3 was 3.33g, the second compound MgO was 2.42g, the third compound Ta2O5 was 6.63g, and the fifth compound Cr2O3 was 0.06g. The molar ratio of each element in 1 mole of the resulting oxide phosphor was Li3Mg2TaO6:Cr 0.026 The other components were weighed out so that the molar ratio of the charged composition was the same as in Example 1, and an oxide phosphor of Example 2 having the composition shown in Table 1 was obtained. In the composition of the oxide phosphor of Example 2 shown in Table 1, the variable q in the formula (1) is 0 (q=0), the variable r is 3 (r=3), the variable s is 0 (s=0), the variable t is 2 (t=2), the variable u is 0 (u=0), the variable v is 0 (v=0), the variable w is 1 (w=1), the variable x is 6 (x=6), the variable y is 0.026 (y=0.026), and the variable z is 0 (z=0).

[0097] Example 3 The raw materials were weighed out so that the first compound Li2CO3 was 3.33g, the second compound MgO was 2.42g, the third compound Ta2O5 was 6.63g, and the fifth compound Cr2O3 was 0.09g. The molar ratio of each element in 1 mole of the resulting oxide phosphor was Li3Mg2TaO6:Cr 0.04 The other components were weighed out so that the molar ratio of the charged composition was the same as in Example 1, and an oxide phosphor of Example 3 having the composition shown in Table 1, which is the molar ratio of the charged composition, was obtained. In the composition of the oxide phosphor of Example 3 shown in Table 1, the variable q in the formula (1) is 0 (q=0), the variable r is 3 (r=3), the variable s is 0 (s=0), the variable t is 2 (t=2), the variable u is 0 (u=0), the variable v is 0 (v=0), the variable w is 1 (w=1), the variable x is 6 (x=6), the variable y is 0.04 (y=0.04), and the variable z is 0 (z=0).

[0098] Example 4 The raw materials were weighed out so that the first compound Li2CO3 was 3.33g, the second compound MgO was 2.42g, the fourth compound Nb2O5 was 3.99g, and the fifth compound Cr2O3 was 0.06g. The molar ratio of each element in 1 mole of the resulting oxide phosphor was Li3Mg2NbO6:Cr 0.026 The other components were weighed out so that the molar ratio of the charged composition was the same as in Example 1, and an oxide phosphor of Example 4 having the composition shown in Table 1 was obtained. In the composition of the oxide phosphor of Example 4 shown in Table 1, the variable q in the formula (1) is 0 (q=0), the variable r is 3 (r=3), the variable s is 0 (s=0), the variable t is 2 (t=2), the variable u is 1 (u=1), the variable v is 0 (v=0), the variable w is 1 (w=1), the variable x is 6 (x=6), the variable y is 0.026 (y=0.026), and the variable z is 0 (z=0).

[0099] Example 5 The raw materials were weighed out so that the first compound Li2CO3 was 3.33g, the second compound MgO was 2.42g, the fourth compound Nb2O5 was 3.99g, and the fifth compound Cr2O3 was 0.09g. The molar ratio of each element in 1 mole of the resulting oxide phosphor was Li3Mg2NbO6:Cr 0.04 The other components were weighed out so that the molar ratio of the charged composition was the same as in Example 1, and an oxide phosphor of Example 5 having the composition shown in Table 1 was obtained. In the composition of the oxide phosphor of Example 5 shown in Table 1, the variable q in the formula (1) is 0 (q=0), the variable r is 3 (r=3), the variable s is 0 (s=0), the variable t is 2 (t=2), the variable u is 1 (u=1), the variable v is 0 (v=0), the variable w is 1 (w=1), the variable x is 6 (x=6), the variable y is 0.04 (y=0.04), and the variable z is 0 (z=0).

[0100] Example 6 The raw materials were weighed out so that the first compound Li2CO3 was 3.33g, the second compound MgO was 2.42g, the fourth compound Nb2O5 was 3.99g, and the fifth compound Cr2O3 was 0.15g. The molar ratio of each element in 1 mole of the resulting oxide phosphor was Li3Mg2NbO6:Cr 0.066 The other components were weighed out so that the molar ratio of the charged composition was the same as in Example 1, and an oxide phosphor of Example 6 having the composition shown in Table 1 was obtained. In the composition of the oxide phosphor of Example 6 shown in Table 1, the variable q in the formula (1) is 0 (q=0), the variable r is 3 (r=3), the variable s is 0 (s=0), the variable t is 2 (t=2), the variable u is 1 (u=1), the variable v is 0 (v=0), the variable w is 1 (w=1), the variable x is 6 (x=6), the variable y is 0.066 (y=0.066), and the variable z is 0 (z=0).

[0101] Example 7 The raw materials were weighed out so that the first compound Li2CO3 was 1.11g, the second compound MgO was 3.63g, the fourth compound Ta2O5 was 6.63g, and the fifth compound Cr2O3 was 0.09g. The molar ratio of each element in 1 mole of the resulting oxide phosphor was LiMg3TaO6:Cr 0.04 The other components were weighed out so that the molar ratio of the charged composition was the same as in Example 1, and an oxide phosphor of Example 7 having the composition shown in Table 1 was obtained. In the composition of the oxide phosphor of Example 7 shown in Table 1, the variable q in the formula (1) is 0 (q=0), the variable r is 1 (r=1), the variable s is 0 (s=0), the variable t is 3 (t=3), the variable u is 0 (u=0), the variable v is 0 (v=0), the variable w is 1 (w=1), the variable x is 6 (x=6), the variable y is 0.04 (y=0.04), and the variable z is 0 (z=0).

[0102] Example 8 The raw materials were weighed out so that the first compound Li2CO3 was 1.11g, the second compound MgO was 3.63g, the fourth compound Nb2O5 was 3.99g, and the fifth compound Cr2O3 was 0.09g. The molar ratio of each element in 1 mole of the resulting oxide phosphor was LiMg3NbO6:Cr 0.04 The other components were weighed out so that the molar ratio of the charged composition was the same as in Example 1, and an oxide phosphor of Example 8 having the composition shown in Table 1 was obtained. In the composition of the oxide phosphor of Example 8 shown in Table 1, the variable q in the formula (1) is 0 (q=0), the variable r is 1 (r=1), the variable s is 0 (s=0), the variable t is 3 (t=3), the variable u is 1 (u=1), the variable v is 0 (v=0), the variable w is 1 (w=1), the variable x is 6 (x=6), the variable y is 0.04 (y=0.04), and the variable z is 0 (z=0).

[0103] Example 9 The raw materials were weighed out so that the first compound Li2CO3 was 3.33g, the second compound MgO was 2.42g, the third compound Ta2O5 was 3.31g, the fourth compound Nb2O5 was 1.99g, and the fifth compound Cr2O3 was 0.09g. Each element in 1 mole of the composition of the resulting oxide phosphor was in the molar ratio of Li3Mg2Ta 0.5 Nb 0.5 O6:Cr 0.04 The other components were weighed out so that the molar ratio of the charged composition was the same as in Example 1, and an oxide phosphor of Example 9 having the composition shown in Table 1 was obtained. In the composition of the oxide phosphor of Example 9 shown in Table 1, the variable q in the formula (1) is 0 (q=0), the variable r is 3 (r=3), the variable s is 0 (s=0), the variable t is 2 (t=2), the variable u is 0.5 (u=0.5), the variable v is 0 (v=0), the variable w is 1 (w=1), the variable x is 6 (x=6), the variable y is 0.04 (y=0.04), and the variable z is 0 (z=0).

[0104] Measurement of emission spectrum and emission characteristics The emission spectrum of each oxide phosphor of the examples was measured using a quantum efficiency measurement system (QE-2000, manufactured by Otsuka Electronics Co., Ltd.). The emission peak wavelength of the excitation light of the light-emitting element, which is a semiconductor element, used in the quantum efficiency measurement system was 450 nm. From the emission spectrum of each phosphor obtained, the relative emission intensity, emission peak wavelength, and full width at half maximum were obtained as emission characteristics. That is, the emission peak wavelength (nm) in the emission spectrum of each phosphor and the full width at half maximum (FWHM) (nm) of the emission spectrum at the emission peak wavelength were obtained. The relative emission intensity was calculated by taking the emission intensity of Example 3 as 100%, and the relative emission intensity (%) of the emission intensity of each oxide phosphor was obtained. The results are shown in Table 1. Figures 4 to 6 show the emission spectra of the oxide phosphors according to Examples 1 to 9.

[0105] [Table 1]

[0106] As shown in Table 1 or FIGS. 4 to 6 , the oxide phosphors of Examples 1 to 9 have an emission peak wavelength in the range of 800 nm or more and 860 nm or less in the emission spectrum, more specifically, have an emission peak wavelength in the range of 810 nm or more and 850 nm or less, and can emit light required for analysis in the wavelength range of red light to near-infrared light, more specifically, in the wavelength range of near-infrared light.

[0107] The oxide phosphors according to Examples 1 to 3 and 7 contain Ta, Nb, and a first element M in 1 mol of the composition represented by the formula (1). 1 , second element M 2 , third element M 3 and the fourth element M 4 does not include. In the oxide phosphors according to Examples 1 to 3 and 7, in 1 mole of the composition represented by the formula (1), the variable y representing the molar ratio of Cr, which is an activation element in the formula (1), is in the range of 0.01 to 0.2 (0.01≦y≦0.2), more specifically, in the range of 0.013 to 0.04 (0.013≦y≦0.04). In the oxide phosphors according to Examples 1 to 3 and 7, the relative emission intensity is 90% or more in the emission spectrum, and the relative emission intensity is high. In addition, in the oxide phosphors according to Examples 1 to 3 and 7, the full width at half maximum is in the range of 150 nm to 165 nm in the emission spectrum, and the full width at half maximum is wide, and light having the emission intensity required for analysis can be emitted in the near-infrared wavelength range.

[0108] The oxide phosphors according to Examples 4 to 6 and 8 contain Nb, Ta, and the first element M in 1 mol of the composition represented by the formula (1). 1 , second element M 2 , third element M 3 and the fourth element M 4In the oxide phosphors according to Examples 4 to 6 and 8, in 1 mole of the composition represented by the formula (1), the variable y representing the molar ratio of Cr, which is an activation element in the formula (1), is in the range of 0.01 to 0.2 (0.01≦y≦0.2), more specifically, in the range of 0.025 to 0.07 (0.025≦y≦0.07). In the oxide phosphors according to Examples 4 to 6 and 8, the relative emission intensity is 50% or more in the emission spectrum, and the emission intensity is lower than that of an oxide phosphor having a composition containing Ta and not containing Nb in 1 mole of the composition represented by the formula (1), but the full width at half maximum is in the range of 170 nm to 210 nm, and the full width at half maximum is wider, and light having an emission intensity required for analysis can be emitted in the wavelength range of near-infrared light.

[0109] The oxide phosphor according to Example 9 contains both Ta and Nb in 1 mol of the composition represented by the formula (1), and the first element M 1 , second element M 2 , third element M 3 and the fourth element M 4 does not contain. In the oxide phosphor according to Example 9, in 1 mole of the composition represented by formula (1), the variable y representing the molar ratio of Cr, which is an activation element in formula (1), is in the range of 0.01 to 0.2 (0.01≦y≦0.2), more specifically, 0.04 (y=0.04). In the emission spectrum of the oxide phosphor according to Example 9, the relative emission intensity is 34% or more, the full width at half maximum is 150 nm or more, and the oxide phosphor according to Example 9 can emit light having an emission intensity required for analysis in the wavelength range of near-infrared light.

[0110] The embodiments according to the present disclosure include the following oxide phosphor and a light emitting device using the same. The embodiments according to the present disclosure preferably include a method for producing the oxide phosphor.

[0111] [Section 1] An oxide phosphor having a composition represented by the following formula (1): (Li 1-q M 1 q ) r (Mg1-s M 2 s ) t (Ta 1-u-v Nb u M 3 v ) w O x :Cr y ,M 4 z (1) (In the above formula (1), M 1 is at least one element selected from the group consisting of Na, K, Rb and Cs, and M 2 is at least one element selected from the group consisting of Zn, Ca, Sr and Ba, and M 3 is at least one element selected from the group consisting of P, V, Sb and Bi, and M 4 is at least one element selected from the group consisting of Ni, Ce, Eu, Fe, Mn, Nd, Tm, Ho, Er, and Yb, and q, r, s, t, u, v, w, x, y, and z satisfy 0≦q≦0.5, 0.5≦r≦3.5, 0≦s≦0.5, 1.8≦t≦3.2, 0≦u≦1.0, 0≦v≦0.3, 0≦u+v≦1.0, 0.8≦w≦1.2, 5.1≦x≦6.9, 0.002≦y≦0.5, and 0≦z≦0.3, respectively. [Section 2] Item 2. The oxide phosphor according to item 1, wherein in formula (1), u and v satisfy u=0 and v=0. [Section 3] Item 3. The oxide phosphor according to item 2, wherein in formula (1), y satisfies 0.01≦y≦0.2. [Section 4] Item 2. The oxide phosphor according to item 1, wherein in formula (1), u and v satisfy u=1.0 and v=0. [Section 5] 5. The oxide phosphor according to item 4, wherein in formula (1), y satisfies 0.01≦y≦0.2. [Section 6] 6. The oxide phosphor according to claim 1, wherein in said formula (1), q and s satisfy q=0 and s=0. [Section 7] Item 7. The oxide phosphor according to any one of items 1 to 6, wherein the full width at half maximum of an emission spectrum having an emission peak wavelength is within a range of 140 nm to 220 nm. [Section 8] Item 8. The oxide phosphor according to any one of items 1 to 7, wherein the oxide phosphor has an emission peak wavelength in the range of 800 nm to 860 nm in an emission spectrum. [Section 9] Item 10. An oxide phosphor according to any one of items 1 to 8, A light emitting element having an emission peak wavelength in the range of 365 nm to 650 nm, which irradiates the oxide phosphor with excitation light. [Industrial Applicability]

[0112] The oxide phosphor according to the present disclosure can also be used in medical light-emitting devices for obtaining information within a living body, light-emitting devices mounted on small mobile devices such as smartphones and smartwatches for managing physical condition, light-emitting devices used in medical devices, light-emitting devices for analytical devices that non-destructively measure internal information of agricultural products such as fruits and vegetables, rice, and foods, and pharmaceuticals, light-emitting devices for plant cultivation that affect the photoreceptors of plants, and light-emitting devices for reflectance spectroscopy measuring devices used to measure film thickness, etc. [Explanation of symbols]

[0113] 10: light-emitting element, 11: semiconductor element, 20: first lead, 30: second lead, 40: molded body, 42: resin part, 50, 51: wavelength conversion member, 52: wavelength conversion member, 53: light-transmitting body, 60: wire, 61: conductive member, 70: phosphor, 71: first phosphor, 72: second phosphor, 73: third phosphor, 74: fourth phosphor, 75: fifth phosphor, 80: adhesive layer, 90: covering member, 100, 200: light-emitting device.

Claims

1. An oxide phosphor having a composition represented by the following formula (1): (Li １－ｑ M １ ｑ ) ｒ (Mg １－ｓ M ２ ｓ ) ｔ (Ta １－ｕ－ｖ Nb ｕ M ３ ｖ ) ｗ O ｘ :Cr ｙ , M ４ ｚ (1) (In the above formula (1), M １ is at least one element selected from the group consisting of Na, K, Rb and Cs, M ２ is at least one element selected from the group consisting of Zn, Ca, Sr and Ba, M ３ is at least one element selected from the group consisting of P, V, Sb and Bi, M ４ is at least one element selected from the group consisting of Ni, Ce, Eu, Fe, Mn, Nd, Tm, Ho, Er, and Yb, and q, r, s, t, u, v, w, x, y, and z each satisfy 0≦q≦0.5, 0.5≦r≦3.5, 0≦s≦0.5, 1.8≦t≦3.2, 0≦u≦1.0, 0≦v≦0.3, 0≦u+v≦1.0, 0.8≦w≦1.2, 5.1≦x≦6.9, 0.002≦y≦0.5, and 0≦z≦0.

3.

2. The oxide phosphor according to claim 1 , wherein in the formula (1), u and v satisfy u=0 and v=0.

3. The oxide phosphor according to claim 2 , wherein in the formula (1), y satisfies 0.01≦y≦0.

2.

4. The oxide phosphor according to claim 1 , wherein in the formula (1), u and v satisfy u=1.0 and v=0.

5. 5. The oxide phosphor according to claim 4, wherein in the formula (1), y satisfies 0.01≦y≦0.

2.

6. The oxide phosphor according to claim 1 , wherein in said formula (1), q and s satisfy q=0 and s=0.

7. 2. The oxide phosphor according to claim 1, wherein the full width at half maximum of an emission spectrum having an emission peak wavelength is within a range of 140 nm to 220 nm.

8. The oxide phosphor according to claim 1 , wherein the oxide phosphor has an emission peak wavelength in the range of 800 nm to 860 nm in an emission spectrum.

9. The oxide phosphor according to any one of claims 1 to 8, A light emitting element having an emission peak wavelength in the range of 365 nm to 650 nm, which irradiates the oxide phosphor with excitation light.

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