Abstract: A method for producing a polytetrafluoroethylene particle, which includes subjecting tetrafluoroethylene to suspension polymerization in an aqueous medium to prepare a suspension-polymerized particle of polytetrafluoroethylene, washing and then crushing the suspension-polymerized particle or crushing the suspension-polymerized particle with washing to prepare a crushed particle, dehydrating the crushed particle to prepare a crushed particle having a water content of 40% by mass or less, and subjecting the dehydrated crushed particle to heat treatment to produce a polytetrafluoroethylene particle.

Abstract: A method for producing a polytetrafluoroethylene powder, which includes subjecting tetrafluoroethylene to suspension polymerization in an aqueous medium to prepare a suspension-polymerized particle of non melt-processible polytetrafluoroethylene, drying the suspension-polymerized particle to prepare a dry particle, subjecting the dry particle to fluorine radical treatment to prepare a fluorine radical-treated particle, and crushing the fluorine radical-treated particle to produce a polytetrafluoroethylene powder. Also disclosed is a polytetrafluoroethylene formed article obtained by forming the polytetrafluoroethylene powder, as well as a polytetrafluoroethylene compression-molded article obtained by compression molding the polytetrafluoroethylene powder.

Abstract: A piston rod of a shock absorber includes a pipe material formed of a fiber material and a resin material, and connection members provided to the ends of the pipe material. The pipe material has an inner peripheral surface which has not been subjected to processing for cutting the fiber material, and the connection members have joint parts that are inserted into the inner peripheral surface and are joined to the pipe material with an adhesive.

Abstract: A high pressure discharge lamp comprises a pair of electrodes that face each other in an electric discharge container, wherein an electrode axis of each electrode is buried in a sealing portion, each electrode axis is joined to a metallic foil, two or more grooves are formed in an axis direction on a portion of the electrode axis, which corresponds to the sealing portion, an upper shoulder portion of each groove is formed in a shape of a curved surface, a diameter of the electrode axis is 0.3 mm to 1 mm, and a curvature radius of the curved surface upper shoulder portion is 5 ?m-50 ?m.

Abstract: A high pressure discharge lamp light source device is provided having a quartz glass discharge vessel enclosing two opposed electrodes that are spaced apart by at most 2.0 mm, each electrode having a projection formed at a tip end thereof, at least 0.20 mg/mm3 of mercury and a halogen; and a power supply device for supplying alternating current to the lamp, The power supply device is adapted to switch between a nominal electric power lighting mode and a low electric power lighting mode having a defined current value in a range of 40 to 70% of a nominal electric power consumption. In the low power mode, the power supply alternately supplies a base current in a range between 100 Hz and 5 kHz a boost current having a higher current value than that of the base current.

Abstract: An extra high pressure mercury lamp that includes an arc tube, which includes a light emission section enclosing 0.2 mg/mm3 or more of mercury, sealing sections that respectively extend from both ends of the light emission section, a pair of electrodes that face each other in the light emission section, wherein an electrode axis portion of each electrode is held by the sealing portion, and a metallic foil that is buried in the sealing section and that is electrically connected with the electrode axis portion, wherein the metallic foil has a covering portion fixed to the electrode axis portion so as to roll up the electrode axis portion; an extended portion that extends towards the outside of a tube axis without being connected with the electrode axis portion; and a main body portion that extends from the extended portion.

Abstract: A high pressure discharge lamp comprises a pair of electrodes that face each other in an electric discharge container, wherein an electrode axis of each electrode is buried in a sealing portion, each electrode axis is joined to a metallic foil, two or more grooves are formed in an axis direction on a portion of the electrode axis, which corresponds to the sealing portion, an upper shoulder portion of each groove is formed in a shape of a curved surface, a diameter of the electrode axis is 0.3 mm to 1 mm, and a curvature radius of the curved surface upper shoulder portion is 5 ?m-50 ?m.

Abstract: For maintaining the projections of the electrode tip ends in the ideal condition and maintaining a stable arc even if the lamp is lighted with a lamp power of at most 70% of the rated electric power, a high pressure discharge lamp light source device is provided, comprised of a high pressure discharge lamp having a discharge vessel made from quartz glass and a pair of electrodes arranged oppositely to each other with a spacing of at most 2.0 mm, each electrode having a projection formed at a tip end thereof, and mercury of at least 0.

Abstract: An electrode for an extra-high pressure discharge lamp, comprises large diameter portion which is symmetrical with respect to an axis of the electrode, a small diameter portion connected to the large diameter portion, wherein the large diameter portion is connected to the small diameter portion through an outer surface portion of the electrode, wherein a stripe lines like pattern portion, extending along an electrode axis direction, is formed on a portion to be brought in contact with glass of a lamp, and wherein unevenness is formed over an entire circumference of the electrode in a cross sectional view of the electrode taken along a direction perpendicular to the electrode axis direction.

Abstract: An extra high pressure mercury lamp that includes an arc tube, which includes a light emission section enclosing 0.2 mg/mm3 or more of mercury, sealing sections that respectively extend from both ends of the light emission section, a pair of electrodes that face each other in the light emission section, wherein an electrode axis portion of each electrode is held by the sealing portion, and a metallic foil that is buried in the sealing section and that is electrically connected with the electrode axis portion, wherein the metallic foil has a covering portion fixed to the electrode axis portion so as to roll up the electrode axis portion; an extended portion that extends towards the outside of a tube axis without being connected with the electrode axis portion; and a main body portion that extends from the extended portion.

Abstract: An electrode for an extra-high pressure discharge lamp, comprises large diameter portion which is symmetrical with respect to an axis of the electrode, a small diameter portion connected to the large diameter portion, wherein the large diameter portion is connected to the small diameter portion through an outer surface portion of the electrode, wherein a stripe lines like pattern portion, extending along an electrode axis direction, is formed on a portion to be brought in contact with glass of a lamp, and wherein unevenness is formed over an entire circumference of the electrode in a cross sectional view of the electrode taken along a direction perpendicular to the electrode axis direction.

Abstract: Process for producing a discharge lamp having a silica discharge vessel with an emission space in which there is a pair of electrodes at least 0.15 mg/mm3 of mercury, argon (Ar), and halogen by measuring the relation b/a1 between the emission intensity a1 of argon (Ar) at a wavelength of 668 nm and the emission intensity b of OH radicals at a wavelength of 309 nm in a state of glow discharge of the discharge lamp; supplying hydrogen into the discharge vessel of the discharge lamp; measuring the relation c/a2 between the emission intensity a2 of argon (Ar) at a wavelength of 668 nm and the emission intensity c of OH radicals at a wavelength of 309 nm in the state of glow discharge of the discharge lamp; and fixing the difference c/a2?b/a1 at a value in the range of 0.001 to 15.

Abstract: A wavelength plate including an organic thin film adhered to a glass substrate through an adhesive is built in an optical head optical system used in a predetermined using temperature range. The adhesive has a glass transition temperature higher than the predetermined using temperature range, and the linear expansion coefficient (K1) of the adhesive, the linear expansion coefficient (K2) of the organic thin film, and the linear expansion coefficient (K3) of the glass substrate have the relation of K3?K1 and K1?K2 under the predetermined using temperature range.

Abstract: Process for producing a discharge lamp having a silica discharge vessel with an emission space in which there is a pair of electrodes at least 0.15 mg/mm3 of mercury, argon (Ar), and halogen by measuring the relation b/a1 between the emission intensity a1 of argon (Ar) at a wavelength of 668 nm and the emission intensity b of OH radicals at a wavelength of 309 nm in a state of glow discharge of the discharge lamp; supplying hydrogen into the discharge vessel of the discharge lamp; measuring the relation c/a2 between the emission intensity a2 of argon (Ar) at a wavelength of 668 nm and the emission intensity c of OH radicals at a wavelength of 309 nm in the state of glow discharge of the discharge lamp; and fixing the difference c/a2?b/a1 at a value in the range of 0.001 to 15.