Abstract: Provided are a lubricant that is highly resistant to contamination and highly thermally stable, a lubricant that is highly durable and highly heat resistant, and a magnetic disk. A fluoropolyether compound contains perfluoropolyether groups, end groups each containing at least one hydroxyl group, and a linking group that is comprised of a C4-C14 hydrocarbon group and that contains at least one hydroxyl group.

Abstract: Provided are a lubricant that is highly resistant to contamination and highly thermally stable, a lubricant that is highly durable and highly heat resistant, and a magnetic disk. A fluoropolyether compound contains perfluoropolyether groups, end groups each containing at least one hydroxyl group, and a linking group that is comprised of a C4-C14 hydrocarbon group and that contains at least one hydroxyl group.

Abstract: Systems and methods for applying electric fields during ultraviolet exposure of lubricant layers for hard disk media. One such method involves inserting a magnetic medium into a chamber, the magnetic medium including a lubricant on an outer surface thereof, and applying an electric field and an ultraviolet radiation to the lubricant within the chamber. Another such method involves inserting a magnetic medium into a chamber, depositing a lubricant on the medium within the chamber, and applying an electric field and an ultraviolet radiation to the lubricant within the chamber.

Abstract: Systems and methods for applying electric fields during ultraviolet exposure of lubricant layers for hard disk media. One such method involves inserting a magnetic medium into a chamber, the magnetic medium including a lubricant on an outer surface thereof, and applying an electric field and an ultraviolet radiation to the lubricant within the chamber. Another such method involves inserting a magnetic medium into a chamber, depositing a lubricant on the medium within the chamber, and applying an electric field and an ultraviolet radiation to the lubricant within the chamber.

Abstract: Systems and methods are illustrated for manufacturing hard disks with double lubrication layers that allow minimization of a HDD head DFH touchdown point while maintaining good tribology performance for HDD reliability. An exemplary hard disk includes a magnetic recording layer, a carbon overcoat, and a double lubrication layer: a bonded lubrication layer and a mobile lubrication layer. The bonded lubrication layer includes a high conformity and high density first lubricant. The mobile layer include a high lubricity lubricant that promotes HDI reliability.

Abstract: Systems and methods are illustrated for manufacturing hard disks with double lubrication layers that allow minimization of a HDD head DFH touchdown point while maintaining good tribology performance for HDD reliability. An exemplary hard disk includes a magnetic recording layer, a carbon overcoat, and a double lubrication layer: a bonded lubrication layer and a mobile lubrication layer. The bonded lubrication layer includes a high conformity and high density first lubricant. The mobile layer include a high lubricity lubricant that promotes HDI reliability.

Abstract: A composite lubricant for recording disk media, a recording disk media including a layer of the composite lubricant, and method of manufacturing the same are described. The composite lubricant may include a non-phosphazene component and a phosphazene component where the non-phosphazene component is a difunctional perfluoropolyether compound terminated with first and second polar end groups, the first polar end group comprising a first number of hydroxyls and the second polar end includes a second number of hydroxyls, greater than the first number of hydroxyls. The phosphazene component may be a difunctional perfluoropolyether compound terminated with a phosphazene functional group and with a third polar end group, the third polar end group comprising a third number of hydroxyls equal to the second number of hydroxyls.

Abstract: A composite lubricant for recording disk media, a recording disk media including a layer of the composite lubricant, and method of manufacturing the same are described. The composite lubricant may include a non-phosphazene component and a phosphazene component where the non-phosphazene component is a difunctional perfluoropolyether compound terminated with first and second polar end groups, the first polar end group comprising a first number of hydroxyls and the second polar end includes a second number of hydroxyls, greater than the first number of hydroxyls. The phosphazene component may be a difunctional perfluoropolyether compound terminated with a phosphazene functional group and with a third polar end group, the third polar end group comprising a third number of hydroxyls equal to the second number of hydroxyls.

Abstract: An optical information recording medium having a structure in which irregular reflection of information light and recording/reproducing light from the reflective layer of an optical information record medium is prevented, thereby reducing the noise appearing on the reproduced image. The optical information recording medium for recording information by holography comprises a transparent substrate, a recording layer where information is recorded by an interference pattern, and a filter layer formed between the transparent substrate and the recording layer and adapted to transmit a light of a first wavelength and reflect a light of a second wavelength. The filter layer of the thus structured optical information recording medium transmits a light of the first wavelength (for example, red light) and reflects a light of the second wavelength (for example, green light). As a result, two lights of different wavelengths can be separated and used for different purposes without being influenced by each other.

Abstract: The present invention provides a lubricant for recording media that does not readily decompose, and which has high adhesion to recording media, and a magnetic disk that is durable against continuous sliding under high-speed rotation. The present invention provides a lubricant for recording media containing: a perfluoropolyether compound represented by Formula (1), R1—CH2CF2O—(CF2CF2O)m—(CF2O)n—CF2CH2—R2??(1) wherein R1 represents R represents a C1-4 haloalkyl group, R2 represents —OCH2CH(OH)CH2OH, and m and n are each independently 1-30; and another perfluoropolyether compound represented by Formula (2), R1—CH2CF2O—(CF2CF2O)m—(CF2O)n—CF2CH2—R3??(2) wherein R1, m and n are as defined above and R3 represents —OCH2CH(OH)CH2OCH2CH(OH)CH2OH. The present invention also provides a magnetic disk having a lubricating layer essentially consists of such a lubricant.

Abstract: The present invention provides a lubricant for recording media that does not readily decompose, and which has high adhesion to recording media, and a magnetic disk that is durable against continuous sliding under high-speed rotation. The present invention provides a lubricant for recording media containing: a perfluoropolyether compound represented by Formula (1), R1—CH2CF2O—(CF2CF2O)m—(CF2O)n—CF2CH2—R2??(1) wherein R1 represents R represents a C1-4 haloalkyl group, R2 represents —OCH2CH(OH)CH2OH, and m and n are each independently 1-30; and another perfluoropolyether compound represented by Formula (2), R1—CH2CF2O—(CF2CF2O)m—(CF2O)n—CF2CH2—R3??(2) wherein R1, m and n are as defined above and R3 represents —OCH2CH(OH)CH2OCH2CH(OH)CH2OH. The present invention also provides a magnetic disk having a lubricating layer essentially consists of such a lubricant.

Abstract: It is an object of the invention to provide an optical information recording method which can store information with a simple control, with a high density, and accurately, and which can store information sequentially in holographic storage. A first information group is stored by illuminating a plurality of places of an optical storage medium under a first condition with information light and reference light for storage, and forming a plurality of first illumination regions a1 to a1+2 and c1 to c1+2. A second information group is stored by illuminating a plurality of places of the optical storage medium under a second condition with the information light and the reference light for storage so that second illumination regions overlap the first illumination regions at the same overlapping rate as each other, and forming a plurality of second illumination regions a2 to a2+2 and c2 to c2+2.

Abstract: An optical information-recording medium 1 is constituted by depositing a quarter-wave plate 4, a hologram-recording layer 3 and a reflection layer 5 on a transparent base plate 2 in this order. Reproducing reference light (P-polarized light) passes through the quarter-wave plate 4 to change into a circularly polarized light, and then the circularly polarized light enters the hologram-recording layer 3, so that the reproducing light (circular polarization) generated from the hologram-recording layer 3 passes through the quarter-wave plate 4 to change into a S-polarized light. On the other hand, stray light SL1 (P-polarized light) resulting from the process in which the reproducing light is reflected from the surface of the base plate or in the inside thereof has an vibration direction different from that in the stray light SL2 (P-polarized light) resulting from the process in which the reproducing reference light goes and returns in the inside of the optical information-recording medium 1.

Abstract: A hard disk drive utilizing a combination of thin film recording heads and media allows high density recording through virtual contact recording, while still providing excellent contact start stop performance and low stiction. The air bearing surface of the head has a microscopically fine texture which provides reliable mechanical performance with a constant and very low flying height. A skew insensitive constant flying height over the disk surface can be provided with the use of transverse pressure contour or cross-cut slider designs. The slider air bearing surface is textured by selective mechanical removal of subsurface damaged regions left behind during the diamond lapping of the slider air bearing surface, thereby leaving the slider less abrasive to the disk. A slider with this fine texture on the air bearing surface permits the use of a much smoother texture and thinner overcoat on the disk than currently possible using conventional sliders.