Nitride phosphor particle dispersion-type sialon ceramic, fluorescent member, and method for producing nitride phosphor particle dispersion-type sialon ceramic

A nitride phosphor particle dispersion-type sialon ceramic produced by a method comprising:

• a step of performing uniaxial press molding on a mixture which contains raw material powder serving as a sialon-based compound through a reaction and at least one nitride phosphor containing a luminescence center element to prepare a primary molded body;
• a step of performing cold isostatic press molding on the primary molded body to prepare a secondary molded body;
• a step of performing pre-sintering on the secondary molded body in a nitrogen atmosphere to prepare a sintered body;
• and
• a step of performing a pressure-sintering treatment on the sintered body in a nitrogen atmosphere,
• nitride phosphor particle dispersion-type sialon ceramic comprising:
• a matrix formed of a sialon-based compound;
• and
• at least one nitride phosphor which is dispersed in the matrix and contains a luminescence center element,
• wherein the sialon-based compound is a nitride represented by Formula Mx(Si,Al)y(N,O)z (here, M represents at least one selected from the group consisting of Li, alkaline earth metals, and rare earth metals, 0≤x/z<3, and 0<y/z<1), and
• wherein the nitride phosphor contains a luminescence center element using a nitride represented by Formula Mx(Si,Al)y(N,O)z (here, M represents at least one selected from the group consisting of Li, alkaline earth metals, and rare earth metals, 0≤x/z<3, and 0<y/z<1) as a matrix, and
• the total transmittance of light having a wavelength of 300 nm to 500 nm in a case where a sintered body having a thickness of 100 pin is formed is 10% or greater.