Abstract: A dopant host containing, in terms of mole %, 20 to 50% SiO2, 30 to 60% (exclusive of 30%) Al2O3, 10 to 40% B2O3, and 2 to 10% RO, wherein R represents alkaline earth metal, or being a laminate including a boron component volatilization layer containing, in terms of mole %, 30 to 60% SiO2, 10 to 30% Al2O3, 15 to 50% B2O3, and 2 to 10% RO, wherein R represents alkaline earth metal, and a heat resistant layer containing, in terms of mole %, 8 to 30% SiO2, 50 to 85% Al2O3, 5 to 20% B2O3, and 0.5 to 7% RO, wherein R represents alkaline earth metal. A process for producing a boron dopant for a semiconductor including the steps of slurrying a starting material powder containing a boron-containing crystalline glass powder, forming the slurry to prepare a green sheet, and sintering the green sheet.

Abstract: A dopant host containing, in terms of mole %, 20 to 50% SiO2, 30 to 60% (exclusive of 30%) Al2O3, 10 to 40% B2O3, and 2 to 10% RO, wherein R represents alkaline earth metal, or being a laminate including a boron component volatilization layer containing, in terms of mole %, 30 to 60% SiO2, 10 to 30% Al2O3, 15 to 50% B2O3, and 2 to 10% RO, wherein R represents alkaline earth metal, and a heat resistant layer containing, in terms of mole %, 8 to 30% SiO2, 50 to 85% Al2O3, 5 to 20% B2O3, and 0.5 to 7% RO, wherein R represents alkaline earth metal. A process for producing a boron dopant for a semiconductor including the steps of slurrying a starting material powder containing a boron-containing crystalline glass powder, forming the slurry to prepare a green sheet, and sintering the green sheet.

Abstract: A dopant host containing, in terms of mole %, 20 to 50% SiO2, 30 to 60% (exclusive of 30%) Al2O3, 10 to 40% B2O3, and 2 to 10% RO, wherein R represents an alkaline earth metal, or including a laminate including a boron component volatilization layer containing, in terms of mole %, 30 to 60% SiO2, 10 to 30% Al2O3, 15 to 50% B2O3, 2 to 10% RO, wherein R represents an alkaline earth metal, and a heat resistant layer containing, in terms of mole %, 8 to 30% SiO2, 50 to 85% Al2O3, 5 to 20% B2O3, and 0.5 to 7% RO, wherein R represents an alkaline earth metal. A process for producing a boron dopant for a semiconductor includes the steps of slurrying a starting material powder containing a boron-containing crystalline glass powder, forming the slurry to prepare a green sheet, and sintering the green sheet.

Abstract: A clamping plate capable of reliably clamping a disk-shaped medium. In the clamping plate, at an imaginary intersecting portion between an imaginary extended surface of a rear surface of an outer peripheral portion of a main body and an imaginary extended surface of a rear surface of an inner peripheral wall of the main body, an annular groove recessed from the imaginary extended surfaces in the directions of the thicknesses of the outer peripheral portion and the inner peripheral wall is formed along an imaginary cross line of the imaginary extended surfaces.

Abstract: An illuminating glass that is capable of shielding of ultraviolet radiation lying on the large wavelength side, for example, 313 nm, and exhibits high transparency. The illuminating glass is characterized by containing, by mass, 50-78% SiO2, 11-25% B2O3, 0-10% Al2O3, 3-20% Li2O+Na2O+K2O, 0-10% MgO, 0-10% CaO, 0-20% SrO, 0-20% BaO, 0-15% ZnO, 2.6-9% TiO2 and 0.001-5% AS2O3+Sb2O3.

Abstract: A recording medium storage case includes: a case body including a first case and a second case that is constructed so as to be capable of fitting together with the first case and when fitted together with the first case forms an enclosure capable of storing two recording media; and a holding member that is capable of being fitted inside the enclosure and in which an opening in which one of the recording media can be fitted is formed.

Abstract: A clamping plate capable of reliably clamping a disk-shaped medium. In the clamping plate, at an imaginary intersecting portion between an imaginary extended surface of a rear surface of an outer peripheral portion of a main body and an imaginary extended surface of a rear surface of an inner peripheral wall of the main body, an annular groove recessed from the imaginary extended surfaces in the directions of the thicknesses of the outer peripheral portion and the inner peripheral wall is formed along an imaginary cross line of the imaginary extended surfaces.

Abstract: A cartridge case is constructed so as to be capable of enclosing an information medium inside a cartridge main body that includes a first shell and a second shell and is formed by placing the first shell and the second shell on one another. Cylindrical convex portions, each of which has a positioning reference hole formed in a central portion thereof, are erected on an inner surface of a main plate of the first shell. Insertion holes that allow positioning pins to be inserted into the positioning reference holes of the cylindrical convex portions are formed in a main plate of the second shell.

Abstract: A cartridge case includes: a case main body that has a partition wall, which constructs an enclosure for enclosing a disc-shaped medium, erected on a top surface thereof; an inner rotor that has a main portion and a side wall erected along an outer circumferential edge of the main portion and is rotatably disposed inside the case main body in a state where the side wall is fitted onto an outside of the partition wall; and a shutter that is disposed between the inner rotor and the case main body and moves as the inner rotor rotates, to open and close an access path for accessing the disc-shaped medium. The inner rotor includes bar-shaped protrusions formed on an inner circumferential surface of the side wall in a direction in which the side wall is erected.

Abstract: A clamping plate includes a circular-plate-shaped main plate and a cylindrical outer wall formed by bending an outer edge portion of the main plate. The clamping plate moves due to being pulled by magnetic attraction by a disc rotating mechanism to clamp a disk-shaped recording medium to the disc rotating mechanism. At least one of a convex that protrudes outward in a radial direction of the main plate and a concave that is depressed inward in the radial direction is formed in the outer wall.

Abstract: A disc cartridge includes a cartridge main body composed of a lower shell, in which a first opening that enables disc access for a disc-like recording medium in a housed state is formed, and an upper shell, a disc tray that is rotatably provided inside the cartridge main body and formed so that the recording medium can be mounted thereon, and a single shutter member disposed between the lower shell and the disc tray. A second opening, which enables disc access for the recording medium when the second opening overlaps the first opening in a thickness direction of the disc cartridge, is formed in the disc tray. The disc tray closes part of the first opening in a restricted state where the disc access is restricted, and is capable of opening the part of the first opening in a disc access state by being rotated inside the cartridge main body and causing the shutter member to slide.

Abstract: In a disc cartridge for an optical disc and the like, to increase stiffness in an opening for a record and reproduction mechanism. A disc cartridge 10 has an upper shell 12, a center frame 14, and a lower shell 16 clamped to one another. A center frame opening 20 and a lower shell opening 22 expose a recording surface of a recording medium contained between the center frame 14 and the upper shell 12 downwardly, and a reinforcing member 24 integrally couples the ends of the center frame opening 20, and a lower shell reinforcing member 26 integrally couples the ends of the lower shell opening 22.

Abstract: In a disc cartridge for an optical disc and the like, to increase stiffness in an opening for a record and reproduction mechanism. A disc cartridge 10 has an upper shell 12, a center frame 14, and a lower shell 16 clamped to one another. A center frame opening 20 and a lower shell opening 22 expose a recording surface of a recording medium contained between the center frame 14 and the upper shell 12 downwardly, and a reinforcing member 24 integrally couples the ends of the center frame opening 20, and a lower shell reinforcing member 26 integrally couples the ends of the lower shell opening 22.

Abstract: A disc cartridge includes a cartridge main body composed of a lower shell, in which a first opening that enables disc access for a disc-like recording medium in a housed state is formed, and an upper shell, a disc tray that is rotatably provided inside the cartridge main body and formed so that the recording medium can be mounted thereon, and a single shutter member disposed between the lower shell and the disc tray. A second opening, which enables disc access for the recording medium when the second opening overlaps the first opening in a thickness direction of the disc cartridge, is formed in the disc tray. The disc tray closes part of the first opening in a restricted state where the disc access is restricted, and is capable of opening the part of the first opening in a disc access state by being rotated inside the cartridge main body and causing the shutter member to slide.

Abstract: The disk storage case is composed of a circular setting portion for setting the disk-like member such as a compact disk thereon, a disk holding portion for holding the disk-like member vertically and annularly arranged at a center of a setting face of the setting portion, and a through hole provided at inner side of the annular holding portion. The disk storage case has a simple structure and a lightweight. A plurality of disk storage cases storing the compact disks and others can compactly be stacked and packaged, and by insertion of the cylindrical rod into the through hole and by packing with film, it may easily be packaged without tilting, and the package of a plurality of the disk storage cases can be produced simply and effectively.

Abstract: A cartridge accommodates a recording medium etc, and includes an opening and a shutter for opening and closing the opening. The shutter surface is formed with a hole with which an external drive member engages for driving the shutter. An inner side peripheral surface of the hole, upon which at least the drive member impinges when opening and closing the opening, is constructed of a bending portion continuous from the shutter surface. The bending portion can be worked as a continuous surface by punching out a prepared hole so as to leave a portion corresponding to the bending portion and thereafter bending it. A resinous protection layer having a thickness more than 12 &mgr;m is provided on the shutter surface upon which the drive member impinges when engaging with the hole.

Abstract: A cartridge accommodates a recording medium etc, and includes an opening and a shutter for opening and closing the opening. The shutter surface is formed with a hole with which an external drive member engages for driving the shutter. An inner side peripheral surface of the hole, upon which at least the drive member impinges when opening and closing the opening, is constructed of a bending portion continuous from the shutter surface. The bending portion can be worked as a continuous surface by punching out a prepared hole so as to leave a portion corresponding to the bending portion and thereafter bending it. A resinous protection layer having a thickness more than 12 &mgr;m is provided on the shutter surface upon which the drive member impinges when engaging with the hole.

Abstract: A disk cartridge has a casing composed of upper and lower casings 1,2 which are adapted to rotatably receive therein a disk-like medium 4, a shutter 5 attached to the casing so as to open and shut openings for driving shaft insertion holes 11, 12 and magnetic head insertion holes 12, 22 formed in the upper and lower casings 1,2, a disk-like medium taking-out port 15 formed in the casing and a cover member 3 for opening and closing the disk-like medium taking-out port 15, wherein the cover member 3 is disposed in the casing at a position opposing the shutter 5; a disk-like medium placing portion is provided by forming tongue-like projections 36 in the cover member 3 to support the disk-like member 4 from its lower surface side; the cover member 3 is so arranged as to slide between the upper and lower casings 1,2, whereby the disk-like member 4 can be taken out by simply drawing the cover member 3 from the disk-like medium taking-out port 15 or the disk-like medium 4 can be placed by simply inserting it, and op

Abstract: A disc cartridge capable of enhancing operability of both a cover and an erasure preventing plug while ensuring smooth removal of a disc shaped medium therefrom. An upper casing member and a lower casing member are formed with cutouts, respectively, and the cover is provided with projections fitted in the cutouts of the upper casing member and lower casing member, respectively. The cutouts of the upper casing member and lower casing member and the projections of the cover cooperate with each other to provide an operation hole for the erasure preventing plug and a detection hole therefor, respectively.

Abstract: A disk storage case comprising a main body and a cover body. The main body stores a disk-shaped medium therein and includes a bottom wall having a plurality of hold projections, side walls including extension portions extended therefrom, a front surface wall, and a back surface wall. The cover body includes a top wall, a pair of mutually opposing side walls, and a back surface wall, and the end portions of the pair of side walls of the cover body on the back surface wall side thereof is capable of being pivotally mounted on the extension portions to thereby mount the cover body on the main body in such a manner that the cover body can be opened and closed. The height of the back surface wall of the cover body is set substantially equal to the thickness of the disk storage case when the cover body is closed.