Abstract: Embodiments in accordance with the present invention reduce the number of errors caused by the aged deterioration of a heater for adjusting the clearance between a head and a disk. According to one embodiment, a thermal fly height control (TFC) controller executes the measurement of a resistance value of a heater in a predetermined timing. The TFC controller judges whether or not the measured resistance value falls within a predetermined reference range. If the measured resistance value falls within the reference range, the processing ends without performing any other processing. If the measured resistance value goes out of the reference range, the TFC controller executes error handling processing in response to a resistance failure. As one of the error handling processing, the TFC controller notifies the host that the abnormality (resistance failure) has been detected in the resistance value of the TFC heater.

Abstract: Embodiments of the present invention allow for a precise altitude to be calculated from read-out signals of a head slider. In one embodiment, a hard disk controller/multiprocessing unit (HDC/MPU) determines a head element portion in which the instability has occurred in accordance with the resolution change. The HDC/MPU adjusts the clearance accordingly. The head element portion reads signals of different frequencies under a condition of the signal strengths coinciding with a reference value, and the HDC/MPU calculates the resolution. The HDC/MPU determines that the instability has occurred if the difference is outside the criterion. The HDC/MPU uses the read-out signal of a head slider in which the instability has not occurred to calculate the altitude.

Abstract: Embodiments of the present invention provide a process that monitors a magnetic playback signal while gradually increasing an electricity supply amount for a heater to thereby determine contact between a magnetic head slider and a magnetic disk medium. According to one embodiment, after components for configuring a magnetic recording/playback portion are assembled into a housing, magnetic information is played back on a specific track of a magnetic disk medium by using a playback element while gradually increasing an electricity supply amount for a heater of a magnetic head slider. An amplitude of a playback signal is measured at a plurality of portions along a circumferential direction of the track. Contact between the magnetic head slider and the magnetic disk medium is detected in accordance with an increase in variation in the measured amplitude.

Abstract: Embodiments of the invention reduce a possibility that a head will collide with a medium when the clearance between the head and the medium is adjusted by using a medium, and sufficiently reduce the clearance even at an initial stage of accessing a data area. In one embodiment, a hard disk drive (HDD) keeps a heater in an OFF state for a period of time from the start of seek operation until the specified timing after a following mode starts. This prevents a head element from colliding with a magnetic disk, and also prevents flying properties from changing due to the deformation of the ABS. In the above specified timing, the heater is switched from OFF to ON. Specifically, for example, on completion of seek operation, in the timing in which a head arrives at a target track, or in the timing in which an HDC/MPU enters the following mode, the heater is turned ON.

Abstract: A water-based ink for ink-jet recording contains water, a water-soluble organic solvent, a coloring agent and a crown ether. Even when the water-based ink is employed in the ink passage of an ink-jet recording apparatus and comes into contact with rubber members employed in the ink passage, the occurrence of precipitation is prevented.

Abstract: Embodiments of the invention reduce a possibility that a head will collide with a medium when the clearance between the head and the medium is adjusted by using a medium, and sufficiently reduce the clearance even at an initial stage of accessing a data area. In one embodiment, a hard disk drive (HDD) switches a heater from OFF to ON in the specified timing after a seek mode is switched to a following mode. Specifically, for example, on the completion of seek operation, in the timing in which a head arrives at a target track, or in the timing in which an HDC/MPU enters the following mode, the heater is turned ON, and this state is kept unchanged until access to the target sector is made.

Abstract: Embodiments in accordance with the present invention reduce the structural stress applied to a head, and to achieve the effective control, when the clearance between the head and a disk is adjusted by using a heater. According to one embodiment, the hard disk controller/microprocessing unit (HDC/MPU) controls a slew rate of a heater at the time of TFC (Thermal Fly height Control). In response to processing conditions, a HDC/MPU changes a slew rate of the output of electric current/voltage applied to the heater. This makes it possible to reduce the head stress, and to achieve the effective TFC. To be more specific, with reference to a temperature/slew rate table, the HDC/MPU changes a slew rate in response to the temperature in the read/write processing.

Abstract: Embodiments in accordance with the present invention relate to improving error recovery process performance. A head slider in an embodiment of this invention includes a heater for adjusting a clearance between a head element section and a magnetic disk. During an error recovery process (ERP) for a reading error, if a particular environmental temperature is in a low-temperature region, a microprocessing unit (MPU) executes the ERP steps of increasing a heater power value of the heater (i.e., STEP X to STEP X+2), preferentially over the ERP steps of reducing the heater power (i.e., STEP X+3 to STEP X+5). In the low-temperature region, the possibility of error recovery in an earlier step can be raised by executing the heater power increasing ERP steps earlier than the heater power reducing ERP steps.

Abstract: A water-based ink for ink-jet recording contains water, a water-soluble organic solvent, a coloring agent and a crown ether. Even when the water-based ink is employed in the ink passage of an ink-jet recording apparatus and comes into contact with rubber members employed in the ink passage, the occurrence of precipitation is prevented.

Abstract: A preservative solution contains water, a water-soluble organic solvent and a crown ether. Even when the preservative solution is employed in the ink passage of an ink-jet recording apparatus and comes into contact with rubber members employed in the ink passage, the occurrence of precipitation is prevented.

Abstract: A water base ink set for ink-jet recording includes a water base ink which contains an acid dye, and a water base ink which contains a basic dye. The water base ink contains a polymer which has an average molecular weight of 3,000 to 20,000 and which is represented by the following formula (1): wherein X represents H or COONa, and Y represents H, COONa, SO3Na, or CH2OR in the formula (1). R represents a substituted group having SO3Na with carbon atom or atoms of a number of 1 to 5. When the ink containing the acid dye and the ink containing the basic dye are mixed with each other, then the head discharge section is prevented from any clog-up, and it is possible to perform the stable jetting operation.

Abstract: The ink-jet recording apparatus has an-ink passage into which a water-based ink or a preservation solution is filled. The ink passage employs a rubber member formed from an ethylene propylene diene rubber in which a sulfenamide-based vulcanization accelerator or a thiazole-based vulcanization accelerator is employed. The water-based ink has a dynamic surface tension at a lifetime of 100 ms of about 35 mN/m to about 45 mN/m as measured by means of a maximum bubble pressure method at a measurement temperature of 25° C. Furthermore, the preservation solution has a dynamic surface tension at a lifetime of 100 ms of about 30 mN/m to about 35 mN/m as measured by means of the maximum bubble pressure method at a measurement temperature of 25° C.

Abstract: An ink-jet recording apparatus includes a rubber member in an ink flow passage. The rubber member is made of a rubber composition including a rubber base polymer selected from ethylene-propylene diene rubber polymer and isobutylene-isoprene rubber polymer, and at least one trapping agent selected from calcium carbonate, silicon dioxide, talc, and clay. The trapping agent is effective for absorb-trapping various types of additives that may be present in the rubber member. The additives in the rubber are thereby held in the rubber structure and prevented from being eluted into the water-based ink or the preservative solution, which can lead to clogging of ink nozzles and the like.

Abstract: Embodiments of the invention reduce a possibility that a head will collide with a medium when the clearance between the head and the medium is adjusted by using a medium, and sufficiently reduce the clearance even at an initial stage of accessing a data area. In one embodiment, a hard disk drive (HDD) keeps a heater in an OFF state for a period of time from the start of seek operation until the specified timing after a following mode starts. This prevents a head element from colliding with a magnetic disk, and also prevents flying properties from changing due to the deformation of the ABS. In the above specified timing, the heater is switched from OFF to ON. Specifically, for example, on completion of seek operation, in the timing in which a head arrives at a target track, or in the timing in which an HDC/MPU enters the following mode, the heater is turned ON.

Abstract: Embodiments of the invention reduce a possibility that a head will collide with a medium when the clearance between the head and the medium is adjusted by using a medium, and sufficiently reduce the clearance even at an initial stage of accessing a data area. In one embodiment, a hard disk drive (HDD) switches a heater from OFF to ON in the specified timing after a seek mode is switched to a following mode. Specifically, for example, on the completion of seek operation, in the timing in which a head arrives at a target track, or in the timing in which an HDC/MPU enters the following mode, the heater is turned ON, and this state is kept unchanged until access to the target sector is made.

Abstract: The ink-jet recording apparatus has an ink passage into which a water-based ink or a preservation solution is filled. The ink passage employs a rubber member formed from a rubber in which a butyl rubber polymer serving as a base polymer, zinc oxide serving as a vulcanization agent and a thiazole-based compound serving as a vulcanization accelerator are employed. The water-based ink comprises at least a coloring agent, water and a glycol ether, an amount of the glycol ether being about 5 wt. % to about 10 wt. % with respect to the total weight of the water-based ink. The preservation solution comprises at least water and a glycol ether, an amount of the glycol ether being about 5 wt. % to about 10 wt. % with respect to the total weight of the preservation solution.

Abstract: The ink-jet recording apparatus has an ink passage into which a water based ink or a preservation solution is filled. The ink passage employs a rubber member formed from a rubber which is formed of a butyl rubber polymer, a rubber polymer vulcanizable with an organic peroxide, and an organic peroxide. The water-based ink has a dynamic surface tension at a lifetime of 100 ms of about 35 mN/m to about 45 mN/m as measured by means of a maximum bubble pressure method at a measurement temperature of 25° C. The preservation solution has a dynamic surface tension at a lifetime of 100 ms of about 30 mN/m to about 35 mN/m as measured by means of the maximum bubble pressure method at a measurement temperature of 25° C.

Abstract: An ink-jet recording apparatus has an ink passage into which a water-based ink or a preservation solution is filled. The ink passage employs a rubber member formed from a rubber in which a butyl rubber polymer serving as a base polymer, zinc oxide serving as a vulcanization agent, and a thiourea-based compound serving as a vulcanization accelerator are employed. Each of the water-based ink and the preservation solution comprises water and a water-soluble organic solvent. The ink and the preservation solution contain water in an amount of 70 wt. % to about 85 wt. % with respect to the total weight of the water-based ink and the preservation solution, respectively.

Abstract: The ink-jet recording apparatus has an ink passage into which a water based ink or a preservation solution is filled. The ink passage is formed from a rubber employing organic peroxide and zinc oxide as a vulcanization agent. The ink has a dynamic surface tension at a lifetime of 100 ms of about 35 mN/m to about 45 mN/m as measured by means of a maximum bubble pressure method at a measurement temperature of 25° C. The preservation solution has a dynamic surface tension at a lifetime of 100 ms of about 30 mN/m to about 35 mN/m as measured by means of a maximum bubble pressure method at a measurement temperature of 25° C.

Abstract: In an ink-jet recording apparatus, insoluble materials originating from rubber members employed in an ink passage are prevented from precipitating into a preservation solution or a water-based ink filled into the ink passage. The ink-jet recording apparatus in which the preservation solution or a water-based ink is filled into the ink passage, is configured such that a rubber member employed in the ink passage is formed of a rubber not containing a lubricant.