Abstract: A phosphor including a crystal phase of an aluminate compound containing a metal element M constituting a luminescent center ion and aluminum, in which the crystal phase contains crystallites, and an average size of the crystallites is 2 to 100 ?m.

Abstract: A method for producing a phosphor having a core-shell structure that includes: a core part formed of a crystal phase of an inorganic compound containing a metal element M constituting a luminescent center ion and aluminum; and a shell part containing at least one element selected from the group consisting of boron and silicon and formed on at least a portion of a surface of the core part, the method including: mixing a raw material of the crystal phase and a raw material of the shell part; and heating the obtained mixture at a temperature at which the raw material of the shell part is liquefied, but a host crystal of a phosphor to be obtained is maintained, in which the raw material of the crystal phase contains a raw material compound having D50 in a particle diameter distribution of 0.2 to 90 ?m and containing aluminum.

Abstract: A phosphor having an elemental composition represented by the following composition formula: SryMg(1?x)MxAlzO(1+y+1.5z) (1), in the formula (1), M represents at least one metal element selected from the group consisting of manganese, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, thulium, and ytterbium, x represents a value of 0.01?x?0.8, y represents a value of 1?y?2, and z represents a value of 10?z?22, wherein a particle diameter D10 at which a cumulative frequency is 10% and a particle diameter D90 at which a cumulative frequency is 90% in a volume-based cumulative particle diameter distribution curve obtained by a laser diffraction scattering method satisfy the following conditions (I) and (II): (I) D90-D10 is less than 67.4 ?m; and (II) D10 is a value of greater than 1.3 ?m and 100 ?m or less.

Abstract: A phosphor having an elemental composition represented by the following composition formula: SryMg(1?x)MxAlzO(1+y+1.5z) (1), in the formula (1), M represents at least one metal element selected from the group consisting of manganese, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, thulium, and ytterbium, x represents a value of 0.01?x?0.8, y represents a value of 1?y?2, and z represents a value of 10?z?22, wherein a full width at half maximum of an XRD peak at 2?=31.7°±0.5 is less than 0.207.

Abstract: A phosphor having an elemental composition represented by the following composition formula: SryMg(1-x) MxAlzO(1+y+1.5z) (1), in the formula (1), M represents at least one metal element selected from the group consisting of manganese, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, thulium, and ytterbium, x represents a value of 0.01?x?0.8, y represents a value of 1?y?2, and z represents a value of 10?z?22, wherein the phosphor has a specific surface area of less than 2.7 m2/g.

Abstract: A fluorescent material has a core-shell structure. The core contains a crystal phase of an inorganic compound having Formula: MxMgaAlyOzNw (A); M represents a metal; × satisfies 0.001 ? × ? 0.3; a satisfies 0 ? a ? 1.0 - ×; y satisfies 1.2 ? y ? 11.3; z satisfies 2.8 ? z ? 18; and w satisfies 0 ? w ? 1.0. The shell is formed on at least a part of a surface of the core and contains boron and/or silicon. The core has a sodium content of 1700 ppm by mass or less and a specific surface area of 0.01 to 4.30 m2/g. A ratio Y/X of a peak area value Y of boron or silicon to a peak area value X of metal M present in the shell satisfies 0 < Y/X ? 0.095 in an EDX measurement of a cross section of the fluorescent material.

Abstract: A fluorescent material has a core-shell structure. The core contains a crystal phase of an inorganic compound having Formula: MxMgaAlyOzNw (A); M represents a metal; x satisfies 0.001?x?0.3; a satisfies 0?a?1.0?x; y satisfies 1.2?y?11.3; z satisfies 2.8?z?18; and w satisfies 0?w?1.0. The shell is formed on at least a part of a surface of the core and contains boron and/or silicon. The core has a tetrahedral site occupancy of M1 of 0.032 or more and a specific surface area of 0.01 to 4.1 m2/g. A ratio Y/X of a peak area value Y of boron or silicon to a peak area value X of M present in the shell satisfies 0<Y/X?0.095 when EDX measurement of a cross section of the fluorescent material is performed.

Abstract: A cylindrical honeycomb structure 1 has a partition wall 3 forming A channels 5 and B channels 6. The A channels 5 are open at a first end surface 1a and closed at a second end surface 1b. The B channels 6 are closed at the first end surface 1a and open at the second end surface 1b. The B channels 6 include a first B channel 11 and a second B channel 13 extending substantially in parallel to each other. The A channels 5 include first A channels 10, which surround the first B channel at the first end surface, and second A channels 12, which surround the second B channel at the first end surface. The partition wall 3 has a first group partition wall 18, which separates adjacent channels of the first A channels 10 and the second A channels 12 from each other.

Abstract: The columnar honeycomb structure 10 extending along a central axis CL, including a first end surface 10a and a second end surface 10b, and a partition wall 10c forming a plurality of first flow passages Ra and a plurality of second flow passages Rb, in which the first flow passages Ra are opened at the side of the first end surface 10a and plugged at the side of the second end surface 10b, the second flow passages Rb are plugged at the side of the first end surface 10a and opened at the side of the second end surface 10b, and the honeycomb structure includes a circular row W formed by arranging the second flow passages Rb adjoining and partitioned by the partition wall 10c in a circular pattern.

Abstract: A cylindrical honeycomb structure 1 has a partition wall 3 forming A channels 5 and B channels 6. The A channels 5 are open at a first end surface 1a and closed at a second end surface 1b. The B channels 6 are closed at the first end surface 1a and open at the second end surface 1b. The B channels 6 include a first B channel 11 and a second B channel 13 extending substantially in parallel to each other. The A channels 5 include first A channels 10, which surround the first B channel at the first end surface, and second A channels 12, which surround the second B channel at the first end surface. The partition wall 3 has a first group partition wall 18, which separates adjacent channels of the first A channels 10 and the second A channels 12 from each other.

Abstract: A honeycomb structure 100 having a partition wall 112 that forms a plurality of first channels 110a and a plurality of second channels 110b is provided. The first channels 110a are open at a first end surface 100a and closed at a second end surface 100b. The second channels 110 are closed at the first end surface 100a and open at the second end surface 100b. The partition wall 112 has standard walls 112a, which separate the first channels 110a and the second channels 110b from each other, and a common wall 112b, which separates two first channels 110a adjacent to each other at the first end surface 100a, and the standard walls 112a are thicker than the common walls 112b.

Abstract: The production method of the present invention is a method for producing porous aluminum magnesium titanate by forming a mixture containing Al source powder, Mg source powder, Ti source powder and Si source powder as well as a pore-forming agent to obtain a molded body; presintering the obtained molded body; and then sintering the presintered molded body, wherein the content of the pore-forming agent to a total of 100 parts by mass for the Al source powder, Mg source powder, Ti source powder and Si source powder is 5 to 30 parts by mass, the melting point of the Si source powder is 600 to 1300° C., when the elemental composition ratio of Al, Mg, Ti and Si in the mixture is represented by compositional formula (1): Al2(1?x)MgxTi(1+x)O5+aAl2O3+bSiO2 ??(1), x satisfies 0.05?x?0.15, a satisfies 0?a?0.1 and b satisfies 0.05?b?0.15, and the presintered molded body is sintered at 1300 to 1560° C.

Abstract: The invention is to provide an aluminum titanate-based ceramics showing a good mechanical strength. The invention is an aluminum titanate-based ceramics obtained by firing a starting material mixture which contains a titanium element and an aluminum element, and further contains a chromium element and/or a tungsten element. Preferably, a content of a chromium source which contains the chromium element is from 0.001 to 5 parts by mass, and a content of a tungsten source which contains the tungsten element is from 0.001 to 1.0 part by mass relative to 100 parts by mass of the starting material mixture.

Abstract: The columnar honeycomb structure 10 extending along a central axis CL, including a first end surface 10a and a second end surface 10b, and a partition wall 10c forming a plurality of first flow passages Ra and a plurality of second flow passages Rb, in which the first flow passages Ra are opened at the side of the first end surface 10a and plugged at the side of the second end surface 10b, the second flow passages Rb are plugged at the side of the first end surface 10a and opened at the side of the second end surface 10b, and the honeycomb structure includes a circular row W formed by arranging the second flow passages Rb adjoining and partitioned by the partition wall 10c in a circular pattern.

Abstract: A honeycomb structure 100 has a plurality of flow paths 110a and 110b which are partitioned by partition walls 120 and are substantially parallel to each other; and one end of the flow path 110a is plugged by a plugging part 130 at one end surface 100a of the honeycomb structure 100, and one end of the flow path 110b is plugged by a plugging part 130 at the other end surface 100b of the honeycomb structure 100, wherein, in an image of the partition walls 120 obtained by X-ray CT measurement, when the number of communicating holes detected when resolution of the image is 1.5 ?m/pixel is defined as X, and the number of communicating holes detected when resolution of the image is 2.5 ?m/pixel is defined as Y, Y/X is 0.58 or more.

Abstract: A method of manufacturing a honeycomb structure comprises a step of forming a molded article by molding a raw material containing a ceramic powder and a pore-forming agent; and a step of manufacturing a honeycomb structure by sintering the molded article, wherein the pore-forming agent is powder formed of a material that disappears at a sintering temperature or less where the molded article is sintered, the powder is obtained by mixing a small particle size powder and a large particle size powder, a median particle size of which a ratio of a cumulative mass with respect to a total mass of the small particle size powder is 50% is 5 to 20 ?m, a median particle size of which a ratio of a cumulative mass with respect to a total mass of the large particle size powder is 50% is 30 ?m or more, and a ninety-percentage particle size of which a ratio of a cumulative mass with respect to a total mass of the large particle size powder is 90% is 80 ?m or less.

Abstract: A honeycomb structure 100 has a plurality of flow paths 110a and 110b which are partitioned by partition walls 120 and are substantially parallel to each other; and one end of the flow path 110a is plugged by a plugging part 130 at one end surface 100a of the honeycomb structure 100, and one end of the flow path 110b is plugged by a plugging part 130 at the other end surface 100b of the honeycomb structure 100, wherein, in an image of the partition walls 120 obtained by X-ray CT measurement, when the number of communicating holes detected when resolution of the image is 1.5 ?m/pixel is defined as X, and the number of communicating holes detected when resolution of the image is 2.5 ?am/pixel is defined as Y, Y/X is 0.58 or more.

Abstract: A method of manufacturing a honeycomb structure comprises a step of forming a molded article by molding a raw material containing a ceramic powder and a pore-forming agent; and a step of manufacturing a honeycomb structure by sintering the molded article, wherein the pore-forming agent is powder formed of a material that disappears at a sintering temperature or less where the molded article is sintered, the powder is obtained by mixing a small particle size powder and a large particle size powder, a median particle size of which a ratio of a cumulative mass with respect to a total mass of the small particle size powder is 50% is 5 to 20 ?m, a median particle size of which a ratio of a cumulative mass with respect to a total mass of the large particle size powder is 50% is 30 ?m or more, and a ninety-percentage particle size of which a ratio of a cumulative mass with respect to a total mass of the large particle size powder is 90% is 80 ?m or less.