Abstract: A glass ceramic substrate includes: an inner layer part having a first thermal expansion coefficient; and a surface layer part having a second thermal expansion coefficient smaller than the first thermal expansion coefficient. The inner layer part contains a first glass matrix and flat alumina particles. The flat alumina particles are dispersed in the glass matrix in a direction in which individual thickness directions are substantially perpendicular to a surface direction of one of main surfaces of the inner layer part. Further, a mean aspect ratio of the flat alumina particles is 3 or more in one of cross sections along the thickness directions of the flat alumina particles out of cross sections of the inner layer part.

Abstract: To provide a glass ceramic body, whereby light which transmits through the substrate and leaks (i.e. emits) out of the incident direction is reduced, and the number of voids at the surface of the substrate and in the inside of the substrate is low, A glass ceramic body 10 comprising a glass matrix 11 and flat fillers 12 dispersed therein, wherein the flat fillers 12 are dispersed in the glass matrix 11 so that their individual thickness directions would be substantially in the same direction; and in a cross-section along the thickness direction of the flat filler 12 in the glass matrix 11, the occupation area of the flat fillers 12 having a length in their flat direction of from 0.5 to 20 ?m and a length in their thickness direction of from 0.02 to 0.25 ?m per unit area of the cross-section is from 30 to 48%.

Abstract: A glass ceramic substrate includes: an inner layer part having a first thermal expansion coefficient; and a surface layer part having a second thermal expansion coefficient smaller than the first thermal expansion coefficient. The inner layer part contains a first glass matrix and flat alumina particles. The flat alumina particles are dispersed in the glass matrix in a direction in which individual thickness directions are substantially perpendicular to a surface direction of one of main surfaces of the inner layer part. Further, a mean aspect ratio of the flat alumina particles is 3 or more in one of cross sections along the thickness directions of the flat alumina particles out of cross sections of the inner layer part.

Abstract: To provide a substrate for mounting a light-emitting device, which is provided with a silver reflection layer having a high reflectance and being less susceptible to deterioration of the reflectance due to corrosion and which has an improved light extraction efficiency. A substrate for mounting a light-emitting element 1, which comprises a substrate main body 2, a silver reflection layer 6 composed mainly of silver or a silver alloy, formed on the substrate main body 2, and a protective layer formed so as to cover the entire surface of the silver reflection layer 6, wherein the protective layer 7 contains an alumina filler and further contains a glass constituting the protective layer 7, having silver ions diffused therein. The concentration of silver ions contained in the glass of the protective layer 7 is at least 0.5 mass % and at most 5.0 mass %.

Abstract: To provide a glass ceramic body wherein the deterioration of the reflectance due to black coloration is suppressed, and the unevenness of the firing shrinkage is suppressed. A glass ceramic body comprising a glass matrix and alumina particles dispersed therein, wherein the glass matrix is not crystallized, a ceramic part composed of the dispersed alumina particles has an ?-alumina crystal structure and a crystal structure other than the ?-alumina crystal structure.

Abstract: There are provided a glass ceramic body having a sufficiently high strength and having a high degree of flexibility in shape which can correspond to a three-dimensional shape, and a layered body having the glass ceramic body. In a glass ceramic body in which flat alumina particles are dispersed in a glass matrix constituted of a glass with a crystallinity of 25% or less, a total cross-sectional area of the flat alumina particles, having a cross section with a thickness of 0.2 ?m or more, a maximum diameter of 8 ?m or less, and an aspect ratio in a range of 3 to 18 in one of cross sections along the thickness directions of the flat alumina particles in the glass ceramic body, is 20% or more relative to a total area of the cross section, and an open porosity is 5% or less.

Abstract: To provide a glass ceramic body wherein the deterioration of the reflectance due to black coloration is suppressed, and the unevenness of the firing shrinkage is suppressed. A glass ceramic body comprising a glass matrix and alumina particles dispersed therein, wherein the glass matrix is not crystallized, a ceramic part composed of the dispersed alumina particles has an ?-alumina crystal structure and a crystal structure other than the ?-alumina crystal structure.

Abstract: To provide a glass ceramic body, whereby light which transmits through the substrate and leaks (i.e. emits) out of the incident direction is reduced, and the number of voids at the surface of the substrate and in the inside of the substrate is low, A glass ceramic body 10 comprising a glass matrix 11 and flat fillers 12 dispersed therein, wherein the flat fillers 12 are dispersed in the glass matrix 11 so that their individual thickness directions would be substantially in the same direction; and in a cross-section along the thickness direction of the flat filler 12 in the glass matrix 11, the occupation area of the flat fillers 12 having a length in their flat direction of from 0.5 to 20 ?m and a length in their thickness direction of from 0.02 to 0.25 ?m per unit area of the cross-section is from 30 to 48%.

Abstract: To provide a substrate for mounting a light-emitting device, which is provided with a silver reflection layer having a high reflectance and being less susceptible to deterioration of the reflectance due to corrosion and which has an improved light extraction efficiency. A substrate for mounting a light-emitting element 1, which comprises a substrate main body 2, a silver reflection layer 6 composed mainly of silver or a silver alloy, formed on the substrate main body 2, and a protective layer formed so as to cover the entire surface of the silver reflection layer 6, wherein the protective layer 7 contains an alumina filler and further contains a glass constituting the protective layer 7, having silver ions diffused therein. The concentration of silver ions contained in the glass of the protective layer 7 is at least 0.5 mass % and at most 5.0 mass %.