Abstract: A solid titanium catalyst component (I) for olefin polymer production contains titanium, magnesium, halogen, and a cyclic multiple-ester-group-containing compound (a) represented by the formula (1). Preferably, a propylene polymer that is obtained by the olefin polymerization method and has specific thermal properties as determined primarily by differential scanning calorimetry (DSC).

Abstract: The solid titanium catalyst component (I) of the present invention contains titanium, magnesium, halogen, and a cyclic multiple-ester-group-containing compound (a) represented by the following formula (1).

Abstract: [Problem] To provide an internal donor component capable of producing, with high productivity, a propylene polymer having extremely high stereoregularity when used mainly as a solid titanium catalyst component. [Solution] A polyol ester compound having a specific polycyclic structure represented by formula (1). This ester compound is characterized in that sites including a C-R3 structure and a C-R4 structure satisfy a specific relationship.

Abstract: The ester compound of the present invention is represented by the following formula (1), wherein R1 to R24 are each independently a hydrogen atom, a halogen atom, a hydrocarbon group, or a hetero atom-containing hydrocarbon group; R1 to R10, R23, and R24 may be bonded to one another to form a ring or may form a multiple bond at which adjacent substituents are directly bonded; R11 to R24 may be bonded to one another to form a ring, or adjacent substituents may be bonded to one another to form a multiple bond; at least one set in R1 to R24 is bonded to one another to form a ring structure; n2 to n5 each independently represent an integer of 0 to 2; n1 and n6 each independently represent an integer of 0 or 1; and L1 and L2 are each independently a hydrocarbon group or a hetero atom-containing hydrocarbon group.

Abstract: A head includes a head body having a medium facing surface, and a protective film covering the medium facing surface. The head body includes a main pole, a waveguide, a plasmon generator, and a main light-blocking section. The waveguide has an entrance end face and an exit end face. The plasmon generator has a near-field light generating surface. The medium facing surface includes a first region including neither of the exit end face and the near-field light generating surface, and a second region including the exit end face and the near-field light generating surface. The protective film includes a first portion covering the first region, and a second portion covering the second region. The main light-blocking section is located to intersect an imaginary straight line connecting the entrance end face and the first region.

Abstract: A thermal assisted magnetic recording head executing magnetic recording while locally heating a magnetic recording medium includes a plasmon generator generating surface plasmon and generating near-field light from the surface plasmon at an end surface situated on an air bearing surface facing the magnetic recording medium, a main pole being in contact with the plasmon generator and exposed on the air bearing surface, a metal protective layer situated on an opposite side to the plasmon generator when viewed from the main pole and positioned to overlap with a part of the main pole when viewed from one side in a down track direction, and an overcoat protective layer covering the metal protective layer. The overcoat protective layer is formed on a flat surface at least at a position where it overlaps with the main pole when viewed from one side in the down track direction, and the metal protective layer configures a part of the flat surface.

Abstract: A thermally assisted magnetic write head includes a waveguide having a first end surface included in an air bearing surface; a magnetic pole having a second end surface included in the air bearing surface; a plasmon generator having a third end surface included in the air bearing surface; a first protective film directly covering a part of the second end surface of the magnetic pole at least; and a second protective film directly covering the first end surface of the waveguide and the third end surface of the plasmon generator. The configuration can reduce recording density and improve thermal stability, furthermore increase the producing yield.

Abstract: The present invention provides a thermally assisted magnetic head with improved recording performance. The thermally assisted magnetic head includes a recording element and a near-field light generating element. The recording element includes a main pole appearing on a medium-facing surface, and a bit inversion starting region intended to be a maximum recording magnetic field generating position is formed at a leading edge of the main pole. The near-field light generating element is located on a leading side of the main pole and capable of creating a heating spot due to a near-field light on a near-field light generating end face appearing on the medium-facing surface. The bit inversion starting region is located within one-half of a diameter of the heating spot from a center of the heating spot.

Abstract: The present invention provides a thermally assisted magnetic head with improved recording performance. The thermally assisted magnetic head includes a recording element and a near-field light generating element. The recording element includes a main pole appearing on a medium-facing surface, and a bit inversion starting region intended to be a maximum recording magnetic field generating position is formed at a leading edge of the main pole. The near-field light generating element is located on a leading side of the main pole and capable of creating a heating spot due to a near-field light on a near-field light generating end face appearing on the medium-facing surface. The bit inversion starting region is located within one-half of a diameter of the heating spot from a center of the heating spot.

Abstract: A thermally assisted magnetic head includes a suspension mounting arrangement facilitating insertion and positioning of a suspension and hardly causes displacement after insertion. The head further includes a slider and a light source unit. The slider has a recording element, a plasmon generating element, a waveguide and a reproducing element at one of opposite ends in a length direction. The recording element and waveguide are disposed adjacent to the plasmon generating element. The light source unit has a laser diode chip and a holder and is disposed on a back surface of the slider opposite from a medium-facing surface. The chip is supported by the holder and optically connected to the waveguide in a height direction. Further, the slider has a groove in a surface of a trailing-side end face for insertion of a suspension. The groove extends linearly along a width direction with bent parts at opposite open ends.

Abstract: A thermally-assisted magnetic recording head includes: a medium facing surface; a magnetic pole; a waveguide including a core and a cladding; a plasmon generator; and a protruding member. The protruding member is disposed between the medium facing surface and a front end face of the core facing toward the medium facing surface. The protruding member has a first end face located in the medium facing surface, and a second end face facing toward the front end face of the core and receiving light having propagated through the core and passed through the front end face. The protruding member is formed of a metal different from both a material forming the magnetic pole and a material forming the plasmon generator. The protruding member is heated and expanded by the light received at the second end face, so that the first end face gets protruded toward a magnetic recording medium.

Abstract: A thermally-assisted magnetic recording head includes a main pole, a waveguide, and a plasmon generator. The main pole has a front end face including first and second ends that are opposite in a track width direction. An arbitrary cross section of the main pole that passes through an arbitrary point on the front end face and is perpendicular to a medium facing surface and to the track width direction has a length in a direction perpendicular to the medium facing surface. When the arbitrary point on the front end face is located at a center of the front end face in the track width direction, the length of the arbitrary cross section is smaller than that when the arbitrary point is located at the first end and that when the arbitrary point is located at the second end.

Abstract: A near-field light generating device includes: a waveguide having a groove that opens in the top surface; a clad layer disposed on the top surface of the waveguide and having an opening that is contiguous to the groove; a near-field light generating element accommodated in the opening; and a buffer layer interposed between the near-field light generating element and each of the waveguide and the clad layer in the groove and the opening. The near-field light generating element includes: first and second side surfaces that decrease in distance from each other toward the groove; an edge part that connects the first and second side surfaces to each other and is opposed to the groove with the buffer layer therebetween; and a near-field light generating part that lies at one end of the edge part and generates near-field light.

Abstract: A near-field light generating device includes: a waveguide; a buffer layer disposed on the top surface of the waveguide; an adhesion layer that is formed by incompletely oxidizing a metal layer and disposed on the buffer layer; and a near-field light generating element disposed on the adhesion layer. The adhesion layer has a resistance-area product higher than that of the metal layer unoxidized and lower than that of a layer that is formed by completely oxidizing the metal layer. A layered structure consisting of the buffer layer, the adhesion layer and the near-field light generating element has a peel-test adhesive strength higher than that of a layered structure consisting of the buffer layer and the near-field light generating element.

Abstract: A near-field light generating device includes: a waveguide; a buffer layer disposed on the top surface of the waveguide; an adhesion layer that is formed by incompletely oxidizing a metal layer and disposed on the buffer layer; and a near-field light generating element disposed on the adhesion layer. The adhesion layer has a resistance-area product higher than that of the metal layer unoxidized and lower than that of a layer that is formed by completely oxidizing the metal layer. A layered structure consisting of the buffer layer, the adhesion layer and the near-field light generating element has a peel-test adhesive strength higher than that of a layered structure consisting of the buffer layer and the near-field light generating element.

Abstract: A near-field light generating device includes: a waveguide having a groove that opens in the top surface; a clad layer disposed on the top surface of the waveguide and having an opening that is contiguous to the groove; a near-field light generating element accommodated in the opening; and a buffer layer interposed between the near-field light generating element and each of the waveguide and the clad layer in the groove and the opening. The near-field light generating element includes: first and second side surfaces that decrease in distance from each other toward the groove; an edge part that connects the first and second side surfaces to each other and is opposed to the groove with the buffer layer therebetween; and a near-field light generating part that lies at one end of the edge part and generates near-field light.