Abstract: A ceiling panel to be fixed to a ceiling base, the ceiling base having a long shape extending in a first direction and being provided in parallel spaced in a second direction orthogonal to the first direction. The ceiling panel includes a panel body in a shape of a rectangular flat plate, a magnet provided on a back face side of both end portions of the panel body in the second direction and being attracted to an attracted portion of the ceiling base, a hooked portion provided for a first end portion of the panel body in the first direction, and a hooking portion provided for a second end portion of the panel body in the first direction, the hooking portion hooking on a hooked portion of an adjacent ceiling panel to be provided in the first direction.

Abstract: A ceiling panel having a connection portion at one of end portions on both sides in a first direction of a panel body in a shape of a rectangular flat plate, the connection portion connecting with a connected portion of an adjacent ceiling panel. The connection portion is fixed to the end portion by a fastener, the fastener being fastened to an insertion part inserted into a layer of the panel body from a cut portion opening on a back face of the end portion so as to penetrate a securing part provided along the back face of the end portion.

Abstract: A ceiling panel of which both end portions in a second direction are held on a ceiling base having a long shape extending in a first direction and being provided in parallel spaced in a second direction the ceiling panel includes a panel body, a hooked portion, and a hooking portion. The hooking portion has a folded part formed by being bent into a room side from a tip end portion in an extending direction of an extension portion extending outward in the first direction from the second end portion in the first direction, and by being further folded inward in the first direction, and the hooked portion keeps hooking and holding of the folded part with a second end portion in the first direction of an adjacent ceiling panel to be provided in the first direction being positioned upward further than the first end portion in the first direction.

Abstract: An adhesive is added to woody fibers obtained by steaming and defibrating a woody material. Then, the woody fibers are formed and are subjected to thermocompression molding. The woody material includes a compressed material obtained by compressing and integrating together a plurality of dried ground products of a Palmae plant.

Abstract: A ceiling panel having a connection portion at one of end portions on both sides in a first direction of a panel body in a shape of a rectangular flat plate, the connection portion connecting with a connected portion of an adjacent ceiling panel. The connection portion is fixed to the end portion by a fastener, the fastener being fastened to an insertion part inserted into a layer of the panel body from a cut portion opening on a back face of the end portion so as to penetrate a securing part provided along the back face of the end portion.

Abstract: A ceiling panel of which both end portions in a second direction are held on a ceiling base having a long shape extending in a first direction and being provided in parallel spaced in a second direction the ceiling panel includes a panel body, a hooked portion, and a hooking portion. The hooking portion has a folded part formed by being bent into a room side from a tip end portion in an extending direction of an extension portion extending outward in the first direction from the second end portion in the first direction, and by being further folded inward in the first direction, and the hooked portion keeps hooking and holding of the folded part with a second end portion in the first direction of an adjacent ceiling panel to be provided in the first direction being positioned upward further than the first end portion in the first direction.

Abstract: A ceiling panel to be fixed to a ceiling base, the ceiling base having a long shape extending in a first direction and being provided in parallel spaced in a second direction orthogonal to the first direction. The ceiling panel includes a panel body in a shape of a rectangular flat plate, a magnet provided on a back face side of both end portions of the panel body in the second direction and being attracted to an attracted portion of the ceiling base, a hooked portion provided for a first end portion of the panel body in the first direction, and a hooking portion provided for a second end portion of the panel body in the first direction, the hooking portion hooking on a hooked portion of an adjacent ceiling panel to be provided in the first direction.

Abstract: A light guide member includes a reflective surface with a diffusion groove array. The diffusion groove array includes diffusion grooves arranged in the reflective surface in a length direction of the light guide member. The diffusion groove array includes, as the diffusion grooves, at least two inspection grooves and a non-inspection diffusion groove. The two inspection grooves are spaced in the length direction of the light guide member. The non-inspection diffusion groove is between the two inspection grooves. An intermediate part, in a length direction, of each of the two inspection grooves is divided by an ungrooved portion with no groove.

Abstract: A light guide member includes a reflective surface with a diffusion groove array. The diffusion groove array includes diffusion grooves arranged in the reflective surface in a length direction of the light guide member. The diffusion groove array includes, as the diffusion grooves, at least two inspection grooves and a non-inspection diffusion groove. The two inspection grooves are spaced in the length direction of the light guide member. The non-inspection diffusion groove is between the two inspection grooves. An intermediate part, in a length direction, of each of the two inspection grooves is divided by an ungrooved portion with no groove.