Patent application number | Description | Published |
20080241603 | Magnetic Disk Glass Substrate - A magnetic disk glass substrate including compressive stress layers at main surfaces and a tensile stress layer between the compressive stress layers formed by chemical strengthening. When the glass substrate has a thickness of less than 0.5 mm and the tensile stress layer has a thickness L and a tensile stress of Pt (kg/mm | 10-02-2008 |
20090142484 | METHOD OF MANUFACTURING MAGNETIC-DISK GLASS SUBSTRATE AND METHOD OF MANUFACTURING MAGNETIC DISK - A process for producing a glass substrate for magnetic disk through chemical strengthening operation, in which the distribution of compressive stress is uniformed at a surface layer portion of the glass substrate to thereby, while preventing failures such as head crash and thermal asperity, realize a low flying height of magnetic head, attaining high-density information recording. In particular, the provided glass substrate for magnetic disk is suitable for application to compact magnetic disks for portable information equipment. The chemical strengthening operation includes the first step of bringing the glass substrate into contact with a first treatment solution (chemical strengthening treatment solution) containing first ions with an ionic radius larger than those of ions within the glass substrate and either the second and subsequent steps of bringing the platy glass into contact with treatment solutions containing second and subsequent bivalent ions, or the second and subsequent steps of bringing the glass substrate into contact with second and subsequent chemical strengthening treatment solutions containing second and subsequent ions exhibiting an ion exchange rate with ions within the glass substrate greater than that of the first ions to thereby decelerate the ion exchange. | 06-04-2009 |
20110102945 | MAGNETIC DISK SUBSTRATE, METHOD FOR MANUFACTURING THE SAME, AND MAGNETIC DISK - Provided are a magnetic disk substrate that can be adapted to a reduction in flying height of a head in an HDD and to an increase in rotational speed therein, and a method of manufacturing such a substrate. | 05-05-2011 |
20110129693 | MAGNETIC DISK GLASS SUBSTRATE - A magnetic disk glass substrate including compressive stress layers at main surfaces and a tensile stress layer between the compressive stress layers formed by chemical strengthening. When the glass substrate has a thickness of less than 0.5 mm and the tensile stress layer has a thickness L and a tensile stress of Pt (kg/mm | 06-02-2011 |
20110159320 | GLASS SUBSTRATE FOR MAGNETIC DISK AND MANUFACTURING METHOD THEREOF - The present invention provides a glass substrate for magnetic disk in which surface irregularity of a principal surface is suppressed and a method for efficiently manufacturing a glass substrate for magnetic disk. The method includes the steps of: forming a sheet glass material by performing press forming to molten glass, a principal surface of the sheet glass material having target flatness for the glass substrate for magnetic disk, the sheet glass material having a surface shape to be ground using a grinding abrasive grain; grinding the sheet glass material using a fixed abrasive grain; and polishing the sheet glass material using a loose abrasive grain, the sheet glass material having surface irregularity of the principal surface ground using the fixed abrasive grain. | 06-30-2011 |
20110159321 | GLASS SUBSTRATE FOR MAGNETIC DISK AND MANUFACTURING METHOD THEREOF - The present invention provides a method for efficiently manufacturing a glass substrate for magnetic disk having good accuracy of a surface irregularity and an impact resistance. The method includes the steps of: performing press forming to molten glass to prepare a sheet glass material, the sheet glass material having a roughness of the principal surface of 0.01 μm or less and target flatness of a glass substrate for magnetic disk; chemically strengthening the sheet glass material by dipping the sheet glass material in a chemically strengthening salt, thereby preparing a disk substrate; polishing the principal surfaces of the disk substrate. A thickness of the sheet glass material prepared in the press forming step is larger than a target thickness of the glass substrate for magnetic disk by a polishing quantity of the principal surface polishing step. | 06-30-2011 |
20110277508 | MANUFACTURING METHOD OF GLASS BLANK FOR MAGNETIC RECORDING GLASS SUBSTRATE, MANUFACTURING METHOD OF MAGNETIC RECORDING GLASS SUBSTRATE AND MANUFACTURING METHOD OF MAGNETIC RECORDING MEDIUM - Provided is a method of manufacturing a glass blank for a magnetic recording medium glass substrate, including: manufacturing a glass blank by at least press molding a falling molten glass gob with a pair of press molds both so as to face each other in a direction perpendicular to a direction in which the molten glass gob falls, in which: the molten glass gob is formed of a glass material having a glass transition temperature of 600° C. or more; and when the press molding is carried out so that the molten glass gob is completely extended by pressure and molded into a flat glass between press-molding surfaces of the pair of press molds, at least a region in contact with the flat glass in each of the press-molding surfaces of the pair of press molds forms a substantially flat surface. Also provided are a method of manufacturing a magnetic recording medium glass substrate and a method of manufacturing a magnetic recording medium each using the method of manufacturing a glass blank for a magnetic recording medium glass substrate. | 11-17-2011 |
20110283739 | METHOD FOR MANUFACTURING GLASS BLANK, METHOD FOR MANUFACTURING MAGNETIC RECORDING MEDIUM SUBSTRATE AND METHOD FOR MANUFACTURING MAGNETIC RECORDING MEDIUM - Provided are a method of manufacturing a glass blank, the method including press-molding a molten glass gob under a state in which a separation mark formed on an upper surface of the molten glass gob faces at least one of the molding surface sides of a pair of press molds arranged facing each other in a horizontal direction, when the molten glass gob falls into a space between the pair of press molds, and a method of manufacturing a magnetic recording medium substrate and a method of manufacturing a magnetic recording medium, both using the glass blank. | 11-24-2011 |
20120135153 | GLASS SUBSTRATE FOR MAGNETIC DISK AND MANUFACTURING METHOD OF THE SAME - A glass substrate for a magnetic disk of the invention is a disk-shaped glass substrate for a magnetic disk where the substrate has a main surface and end face and is subjected to chemical reinforcement treatment, and is characterized in that the penetration length in the uppermost-portion stress layer on the main surface is 49.1 μm or less, and that assuming that an angle between the main surface and compressive stress in the stress profile by a Babinet compensator method is θ, a value y of {12·t·ln(tan θ)+(49.1/t)} is the penetration length in the uppermost-portion stress layer or less. | 05-31-2012 |
20120247155 | METHOD OF MANUFACTURING GLASS BLANK FOR MAGNETIC RECORDING MEDIUM GLASS SUBSTRATE, METHOD OF MANUFACTURING MAGNETIC RECORDING MEDIUM GLASS SUBSTRATE, METHOD OF MANUFACTURING MAGNETIC RECORDING MEDIUM, AND APPARATUS FOR MANUFACTURING GLASS BLANK FOR MAGNETIC RECORDING MEDIUM GLASS SUBSTRATE - A method of manufacturing a glass blank for a magnetic recording medium glass substrate in which, after a pair of press molds placed so as to be opposed to each other in a horizontal direction with press-molding surfaces thereof and the temperatures of the press-molding surfaces being substantially the same are brought into contact with a molten glass gob substantially at the same time, press molding is carried out to produce plate glass and the plate glass continues to be pressed with the pair of molds, and then, when the plate glass is taken out, the duration time of pressing the plate glass is controlled so that the flatness of the glass blank is 10 μm or less, and a method of manufacturing a magnetic recording medium glass substrate, a method of manufacturing a magnetic recording medium, and an apparatus for manufacturing a glass blank for a magnetic recording medium glass substrate using the same. | 10-04-2012 |
20130287938 | METHOD OF MANUFACTURING MAGNETIC-DISK GLASS SUBSTRATE AND METHOD OF MANUFACTURING MAGNETIC DISK - A process for producing a glass substrate for magnetic disk through chemical strengthening operation, in which the distribution of compressive stress is uniformed at a surface layer portion. The chemical strengthening operation includes the first step of bringing the glass substrate into contact with a first treatment solution (chemical strengthening treatment solution) containing first ions with an ionic radius larger than those of ions within the glass substrate and either the second and subsequent steps of bringing the platy glass into contact with treatment solutions containing second and subsequent bivalent ions, or the second and subsequent steps of bringing the glass substrate into contact with second and subsequent chemical strengthening treatment solutions containing second and subsequent ions exhibiting an ion exchange rate with ions within the glass substrate greater than that of the first ions to thereby decelerate the ion exchange. | 10-31-2013 |
20140287269 | GLASS SUBSTRATE FOR A MAGNETIC DISK AND MAGNETIC DISK - Provided are a magnetic disk substrate and a method of manufacturing the same, wherein the magnetic disk substrate has very few defects present on its surface with an arithmetic mean roughness (Ra) at a level in the vicinity of 0.1 nm and thus is suitable as a substrate for a magnetic disk with high recording density. The magnetic disk glass substrate is such that the arithmetic mean roughness (Ra) of the main surface of the glass substrate measured using an atomic force microscope with a resolution of 256×256 pixels in a 2 μm×2 μm square is 0.12 nm or less and the number of defects detected to have a size of 0.1 μm to 0.6 μm in plan view and a depth of 0.5 nm to 2 nm is less than 10 per 24 cm | 09-25-2014 |
Patent application number | Description | Published |
20100188517 | INFORMATION COMMUNICATION TERMINAL - The information communication terminal includes a first housing having a display unit and a second housing having an operating unit. The first housing can be arranged as follows: the first state where the display unit is directed oppositely to the photographing direction of the imaging unit; the second state where the display unit is directed in the photographing direction of the imaging unit; the third state where the rotary shaft direction of the first housing is made to adjoin the direction perpendicular to the open/close shaft direction of the second housing and the display unit and the operating unit are directed to the same side; and fourth state where the direction perpendicular to the rotary shaft direction of the first housing is made to adjoin the open/close shaft direction of the second housing through the hinge and the display unit and the operating unit are directed to the same side. | 07-29-2010 |
20110126097 | INFORMATION PROCESSING APPARATUS, STORAGE MEDIUM HAVING PROGRAM RECORDED THEREON, AND OBJECT MOVEMENT METHOD - An information processing apparatus has a display unit operable to display an object, a contact detection unit operable to detect a plurality of contact points on the display unit, and a control unit operable to control the object displayed on the display unit so as to be movable with use of the contact detection unit. When the control unit detects contact with a display range of the object displayed on the display unit with use of the contact detection unit, detects contact with an active range of a display screen other than the display range of the object, and further detects a movement instruction to the object, then the control unit controls the object so as to be movable within the active range. Thus, use of a contact detection unit capable of a plurality of contact points permits a user's intuitive operation. | 05-26-2011 |
20140333580 | INFORMATION PROCESSING APPARATUS HAVING A CONTACT DETECTION UNIT CAPABLE OF DETECTING A PLURALITY OF CONTACT POINTS, STORAGE MEDIUM HAVING PROGRAM RECORDED THEREON, AND OBJECT MOVEMENT METHOD - An information processing apparatus has a display unit operable to display an object, a contact detection unit operable to detect a plurality of contact points on the display unit, and a control unit operable to control the object displayed on the display unit so as to be movable with use of the contact detection unit. When the control unit detects contact with a display range of the object displayed on the display unit with use of the contact detection unit, detects contact with an active range of a display screen other than the display range of the object, and further detects a movement instruction to the object, then the control unit controls the object so as to be movable within the active range. Thus, use of a contact detection unit capable of a plurality of contact points permits a user's intuitive operation. | 11-13-2014 |