Production method of inorganic fluoride luminescent material

A method for producing an inorganic fluoride luminescent material comprising:

• either preparing a first non-aqueous solution that comprises at least one first ion containing at least one selected from the group consisting of a first element M1 and ammonium, at least one second ion containing a second element M2 other than the first element M1, and a first non-aqueous hydrogen fluoride-containing liquid having a hydrogen fluoride content in a range of 20% by mass or more and 100% by mass or less, and
• a second non-aqueous solution that comprises a third ion containing a third element M3 other than the first element M1 and the second element M2, and a second non-aqueous hydrogen fluoride-containing liquid having a hydrogen fluoride content in a range of 20% by mass or more and 100% by mass or less;
• or
• preparing a third non-aqueous solution that comprises at least one first ion containing at least one selected from the group consisting of a first element M1 and ammonium, at least one second ion containing a second element M2 other than the first element M1, a third ion containing a third element M3 other than the first element M1 and the second element M2, and a third non-aqueous hydrogen fluoride-containing liquid having a hydrogen fluoride content in a range of 20% by mass or more and 100% by mass or less;
• either mixing the first non-aqueous solution and the second non-aqueous solution with a non-aqueous organic liquid having a hydrogen fluoride content of less than 20% by mass, or mixing the third non-aqueous solution with a non-aqueous organic liquid having a hydrogen fluoride content of less than 20% by mass, to precipitate an inorganic fluoride luminescent material containing the first element M1 and/or ammonium, the second element M2, and the third element M3 as a precipitate;
• and
• drying the precipitate at a drying temperature,
• wherein the first element M1 comprises at least one element selected from the group consisting of alkali metal elements and alkaline earth metal elements,
• wherein the second element M2 comprises at least one element selected from the group consisting of non-luminescent transition metal elements, Group 12 elements, Group 13 elements, Group 14 elements, and Group 15 elements,
• wherein the third element M3 comprises at least one element selected from luminescent transition metal elements,
• wherein the mixing of the first non-aqueous solution, the second non-aqueous solution and the non-aqueous organic liquid, or the mixing of the third non-aqueous solution and the non-aqueous organic liquid is performed at a mixing temperature in a range of 15° C. or higher and 40° C. or lower, and
• wherein the drying temperature is lower than the upper limit of the mixing temperature.