Abstract: A lighting device, comprises: a first reflector that includes a first hole where a light source is disposed, a second hole that emits light, and a reflection curved surface that connects the first hole and the second hole to each other, and the first reflector emits light to a first direction; a liquid crystal lens disposed to cover the second hole of the first reflector; and a polygonal pyramid including a bottom surface and a plurality of inclined surfaces, and being disposed so that the plurality of inclined surfaces oppose the liquid crystal lens. The plurality of inclined surfaces are reflection surfaces, and on the reflection surfaces, a traveling path of the light traveling to the first direction changes to a second direction. The liquid crystal lens can configure lenses corresponding to the plurality of inclined surfaces.

Abstract: A nail tip guide tool is attached to an end of a nose of a nailing machine to provide guide pieces on a bottom surface inside same, the nail guide tool having a lower portion in a funnel shape. The top surfaces of the guide pieces have a recess in a mortar shape when brought together at the center of the funnel shape by a press board member biased by a coil spring. The guide pieces are used so that in the nose, the tip of a nail in an inclined posture is guided to a center of the mortar shape and is inserted thereamong, and correcting the posture thereof. For fastening a metal piece with a nail, distal ends of the guide pieces are structured to form a conical shape, and with this portion having been fitted into a pilot hole of the metal piece, the nail is struck.

Abstract: An impact-driven threaded nail includes a threaded portion with a lead angle of about 45°, the threaded portion being defined along an outer circumference of a nail shank that includes a first end defined as a pointed tip; and a head having a larger diameter than the nail shank, the head being integrally provided at a second end of the nail shank, wherein a tapered portion of the head on a back-surface side in continuation with the nail shank is defined in a pyramidal shape having one of regular pentagonal to octagonal cross-sections with a diameter decreasing gradually toward the nail shank, and the threaded nail is configured to be impact-driven and rotate into a mounting member when impacted.

Abstract: In an impact-driven threaded nail, a thread has a steep lead angle of about 45° in order to attach a material with the nail by hitting a nail head and causing the threaded nail to rotate. When external force is applied in a direction to pull back the attached material from an underlying material, the threaded nail is often slightly rotated in a loosening direction, thereby generating a gap between the underlying material and the attached material, particularly in the case of the attached material being a thin sheet such as plywood. The present invention addresses the problem of providing an impact-driven threaded nail equipped with a means for preventing the above-mentioned loosening. The solution means resides in that a tapered portion of the head of the impact-driven threaded nail on a back-surface side thereof is formed in a pyramidal shape having a regular polygonal cross-section with a diameter decreasing gradually toward the nail shank.

Abstract: Diphenylsulfone bridged compounds of the general formula: (1) wherein n is an integer of 1 to 10. Further, there is disclosed a thermal recording material comprising a support and, superimposed thereon, a thermosensitive color forming layer containing a color forming substance for thermal recording consisting of any of the diphenylsulfone bridged compounds and a color forming substance consisting of a colorless or light-colored leuco dye. This thermal recording material excels in the storability, especially wet heat resistance and oil resistance, of image areas and further exhibits excellent characteristics in the storability, especially heat resistance, of undeveloped areas.

Abstract: Diphenylsulfone bridged compounds of the general formula: (1) wherein n is an integer of 1 to 10. Further, there is disclosed a thermal recording material comprising a support and, superimposed thereon, a thermosensitive color forming layer containing a color forming substance for thermal recording consisting of any of the diphenylsulfone bridged compounds and a color forming substance consisting of a colorless or light-colored leuco dye. This thermal recording material excels in the storability, especially wet heat resistance and oil resistance, of image areas and further exhibits excellent characteristics in the storability, especially heat resistance, of undeveloped areas.

Abstract: A color developer for heat sensitive recording which comprises 0.5 to 5 parts by mass of 3-allyl-4-allyloxy-4?-hydroxydiphenylsulfone, 4-allyloxy-3?-allyl-4?-hydroxydiphenylsulfone or a mixture of these compounds per 100 parts by mass of 4-allyloxy-4?-hydroxydiphenylsulfone, a process for producing the color developer and a heat sensitive recording material comprising the color developer in the heat sensitive color forming layer. The color developer and the recording material suppress fog on the background and exhibit excellent color forming property and storage property of image portions.

Abstract: A color developer for heat sensitive recording which comprises 0.5 to 5 parts by mass of 3-allyl-4-allyloxy-4?-hydroxydiphenylsulfone, 4-allyloxy-3?-allyl-4?-hydroxydiphenylsulfone or a mixture of these compounds per 100 parts by mass of 4-allyloxy-4?-hydroxydiphenylsulfone, a process for producing the color developer and a heat sensitive recording material comprising the color developer in the heat sensitive color forming layer. The color developer and the recording material suppress fog on the background and exhibit excellent color forming property and storage property of image portions.

Abstract: A process for producing 2,4?-dihydroxydiphenylsulfone which comprises separating 4,4?-dihydroxydiphenylsulfone by crystallization from a mixture containing 4,4?-dihydroxydiphenylsulfone, 2,4?-dihydroxydiphenylsulfone, phenolsulfonic acid and phenol which is obtained by dehydration of phenol and sulfuric acid or phenolsulfonic acid to obtain a mixture having a content of 2,4?-dihydroxydiphenylsulfone greater than the content of 4,4?-dihydroxydiphenylsulfone, crystallizing 2,4?-dihydroxydiphenylsulfone by adjusting the composition of the solvent of the obtained mixture so that the ratio of the amounts by weight of phenol to water is 10:90 to 90:10, and separating 2,4?-dihydroxydiphenylsulfone by filtration; and a process as described above in which the filtrate obtained by the filtration is used as the raw material for the hydration.

Abstract: A process for producing 2,4?-dihydroxydiphenylsulfone which comprises separating 4,4?-dihydroxydiphenylsulfone by crystallization from a mixture containing 4,4?-dihydroxydiphenylsulfone, 2,4?-dihydroxydiphenylsulfone, phenolsulfonic acid and phenol which is obtained by dehydration of phenol and sulfuric acid or phenolsulfonic acid to obtain a mixture having a content of 2,4?-dihydroxydiphenylsulfone greater than the content of 4,4?-dihydroxydiphenylsulfone, crystallizing 2,4?-dihydroxydiphenylsulfone by adjusting the composition of the solvent of the obtained mixture so that the ratio of the amounts by weight of phenol to water is 10:90 to 90:10, and separating 2,4?-dihydroxydiphenylsulfone by filtration; and a process as described above in which the filtrate obtained by the filtration is used as the raw material for the hydration.

Abstract: A pair of nail shank pieces are united face to face through the intermediary of a strip metal, and the tip parts of both nail shank pieces are tapered so that both nail shank pieces may be gradually opened as the nail is driven in. The metal strip is subjected to a compressive deformation to support the nail shank pieces from inside, thereby helping in their maintaining an opened state. Both nail shank pieces engage the base material in a dovetail fashion and in this way, the countering force against the nail's coming out is reinforced. A clamping ring fit around the outer circumference of both nail shank pieces to hold the metal strip therebetween such that both nail shank pieces are prevented from opening at the base material surface, and moreover, the opening made by the nail at the base material surface is protected from widening, while aiding in both nail shank pieces entering deep into the base material.