Abstract: A red phosphor represented by general formula: MSiAlN3, wherein M is at least one or more elements selected from Mg, Ca, Sr and Ba, and is partially replaced with Eu and has, as a host crystal, a crystal structure identical to that of a CaAlSiN3 crystal phase, and the phosphor has a bulk density of 0.70 g/cm3 or more and 2.30 g/cm3 or less. There is also provided a light-emitting element including the red phosphor and a semiconductor light-emitting element capable of exciting the red phosphor.

Abstract: A phosphor powder composed of ?-sialon phosphor particles containing Eu. The phosphor powder has an ammonium ion concentration CA of the phosphor powder of equal to or more than 15 ppm and equal to or less than 100 ppm, which is determined from the following extracted ion analysis. (Extracted Ion Analysis A) 0.5 g of a phosphor powder is added to 25 ml of distilled water in a polytetrafluoroethylene (PTFE)-made container with a lid and held at 60° C. for 24 hours, and then a total mass MA of ammonium ions included in an aqueous solution obtained by removing a solid content from the solution by filtration is determined using ion chromatography. Then, CA is determined by dividing MA by the mass of the phosphor powder.

Abstract: An europium activating ?-type sialon phosphor contains at least one kind of element selected from the group made of yttrium, titanium, and gadolinium, wherein the total content of the at least one kind of element is more than 0 ppm and less than 1000 ppm.

Abstract: A phosphor powder consists of a red phosphor represented by a general formula (Srx, Ca1-x-y, Euy)AlSi(N,O)3 having the same crystal phase as that of CASN. In a general formula, a relationship of x<1 and 1?x?y>0 are satisfied. In addition, a peak wavelength of a fluorescence spectrum, in a case where the phosphor powder is irradiated with blue excitation light having a wavelength of 455 nm is equal to or more than 600 nm and equal to or less than 610 nm, and a full width at half maximum of the fluorescence spectrum is equal to or less than 73 nm.

Abstract: A phosphor having a main crystal phase having a crystal structure identical to that of CaAlSiN3, and including a Ca element partially replaced with an Eu element, wherein the phosphor has a median size d50 of 12.0 ?m or more and 22.0 ?m or less, as measured according to a laser diffraction scattering method, and has a specific surface area of 1.50 m2/g or more and 10.00 m2/g or less, as measured according to a BET method.

Abstract: A phosphor powder contains an EU-activated ?-type sialon phosphor particles. When a median diameter in the phosphor powder having not been subjected to an ultrasonic homogenizer treatment is set as D1 and a median diameter in the phosphor powder having been subjected to an ultrasonic homogenizer treatment is set as D2, 1.05?D1/D2?1.70. A dispersion liquid in which 30 mg of the phosphor powder is uniformly dispersed in 100 ml of a 0.2% concentration of a sodium hexametaphosphate aqueous solution is added to a columnar container of which a bottom surface has an inner diameter of 5.5 cm. Then, the dispersion liquid is irradiated with ultrasonic waves for 3 minutes at a frequency of 19.5 kHz, and an output of 150 W, in a state where a cylindrical tip, which has an outer diameter of 20 mm, of an ultrasonic homogenizer is immersed in the dispersion liquid in ?1.0 cm.

Abstract: A ?-sialon phosphor that is a solid solution of europium, in which D50 is 7.0 ?m or more and 20.0 ?m or less and (D50?D10)/D50 is 0.60 or less, where D50 is a 50% area diameter of primary particles of the ?-sialon phosphor, and D10 is a 10% area diameter of the primary particles of the ?-sialon phosphor. Primary particles are defined as single-crystal particles distinguished for each crystal orientation by identifying the crystal orientation of individual particles of the ?-sialon phosphor by an electron backscatter diffraction image method. D50 and D10 are obtained by image analysis of the cross-sectional area of the primary particles.

Abstract: A phosphor plate includes a plate-like composite including an inorganic base material, which is a sintered material of two or more types of metal oxide including SiO2, and a phosphor contained in the inorganic base material, in which the phosphor includes an ?-type sialon phosphor, and in a case in which intensity of transmitted light at a wavelength of 455 nm and intensity of reflected light at a wavelength of 455 nm of the phosphor plate are denoted by T1 and R1, respectively, T1 and R1 satisfy 1.5×10?2?T1/R1?5.0×10?2.

Abstract: A europium-doped ?-sialon phosphor particle. When the element concentration of a Si atom on the surface portion of the particle that is obtained by analyzing a cross section of the phosphor particle by the energy dispersive X-ray analysis method is indicated by Ps [at %], and the element concentration of a Si atom near the center of the particle that is obtained by an analysis by the same method is indicated by Pc [at %], the Pc-Ps value is 3 at % or more.

Abstract: An ?-sialon phosphor particle containing Eu. At least one minute recess is formed on a surface of the ?-sialon phosphor particle. The ?-sialon phosphor particle is preferably produced by undergoing a raw material mixing step, a heating step, a pulverizing step, and an acid treatment step.

Abstract: A europium-doped ?-sialon phosphor, in which, when the ratio of an aluminum element at a depth of 8 nm from the surface of the phosphor, which is obtained by X-ray photoelectron spectroscopy, is indicated by P8 [at %], and the ratio of an aluminum element at a depth of 80 nm from the surface of the phosphor is indicated by P80 [at %], P8/P80?0.9 is satisfied. A light emitting device containing this ?-sialon phosphor.

Abstract: A phosphor powder composed of ?-sialon phosphor particles containing Eu. In a case where an internal quantum efficiency after the phosphor powder is held at 600° C. for 1 hour in an air atmosphere is defined as P1 and an internal quantum efficiency after the phosphor powder is held at 700° C. for 1 hour in an air atmosphere is defined as P2, P1 is equal to or more than 70% and (P1?P2)/P1×100 is equal to or less than 2.8%.

Abstract: The purpose of the invention is to both improve the luminance of a SCASN-based phosphor and achieve deep-color rendering properties. Provided is a red phosphor having a main crystal phase having the same crystal structure as a crystal structure of CaAlSiN3, the main crystal phase represented by the general formula MAlSiN3, wherein an internal quantum efficiency, as measured when the red phosphor is excited by light having a wavelength of 455 nm, is 71% or more, and M in the general formula represents an element group containing at least three elements selected from Eu, Sr, Mg, Ca, and Ba, the element group containing Eu, Sr, and Ca as essentials, and a Eu content is 4.5 mass % or more and 7.0 mass % or less, a Sr content is 34.0 mass % or more and 42.0 mass % or less, and a Ca content is 0.8 mass % or more and 3.0 mass % or less.

Abstract: A phosphor powder contains an EU-activated ?-type sialon phosphor particles. When a median diameter in the phosphor powder having not been subjected to an ultrasonic homogenizer treatment is set as D1 and a median diameter in the phosphor powder having been subjected to an ultrasonic homogenizer treatment is set as D2, 1.05?D1/D2?1.70. A dispersion liquid in which 30 mg of the phosphor powder is uniformly dispersed in 100 ml of a 0.2% concentration of a sodium hexametaphosphate aqueous solution is added to a columnar container of which a bottom surface has an inner diameter of 5.5 cm. Then, the dispersion liquid is irradiated with ultrasonic waves for 3 minutes at a frequency of 19.5 kHz, and an output of 150 W, in a state where a cylindrical tip, which has an outer diameter of 20 mm, of an ultrasonic homogenizer is immersed in the dispersion liquid in ?1.0 cm.

Abstract: A phosphor powder composed of ?-sialon phosphor particles containing Eu. With regard to the phosphor powder, a volume-based median diameter (D50) determined by a laser diffraction scattering method is equal to or more than 10 ?m and equal to or less than 20 ?m, and a diffuse reflectance with respect to light at a wavelength of 600 nm is equal to or more than 93% and equal to or less than 99%.

Abstract: An ?-sialon phosphor particle containing Eu. At least one slit is formed on a surface of the ?-sialon phosphor particle. The ?-sialon phosphor particle is preferably produced by undergoing a raw material mixing step, a heating step, a pulverizing step, and an acid treatment step.

Abstract: A nitride fluorescent material represented by General Formula: MAlSiN3 (M=Ca, Sr) in which a part of M is substituted with Eu and a main crystal phase has the same structure as that of a CaAlSiN3 crystal phase, in which a light emission peak wavelength is 640 nm or more, and a half width of the light emission peak wavelength is 80 nm or less.

Abstract: A phosphor powder composed of ?-sialon phosphor particles containing Eu. In a case where an internal quantum efficiency after the phosphor powder is held at 600° C. for 1 hour in an air atmosphere is defined as P1 and an internal quantum efficiency after the phosphor powder is held at 700° C. for 1 hour in an air atmosphere is defined as P2, P1 is equal to or more than 70% and (P1?P2)/P1×100 is equal to or less than 2.8%.

Abstract: A phosphor powder composed of ?-sialon phosphor particles containing Eu. The phosphor powder has an ammonium ion concentration CA of the phosphor powder of equal to or more than 15 ppm and equal to or less than 100 ppm, which is determined from the following extracted ion analysis. (Extracted Ion Analysis A) 0.5 g of a phosphor powder is added to 25 ml of distilled water in a polytetrafluoroethylene (PTFE)-made container with a lid and held at 60° C. for 24 hours, and then a total mass MA of ammonium ions included in an aqueous solution obtained by removing a solid content from the solution by filtration is determined using ion chromatography. Then, CA is determined by dividing MA by the mass of the phosphor powder.

Abstract: An ?-sialon phosphor particle containing Eu. At least one minute recess is formed on a surface of the ?-sialon phosphor particle. The ?-sialon phosphor particle is preferably produced by undergoing a raw material mixing step, a heating step, a pulverizing step, and an acid treatment step.