Abstract: Disclosed is a highly dense aggregate of brittle material particles having an interface at which the particles are bonded to each other and pores between the brittle material particles structuring the highly dense aggregate, where a porosity which is a volume ratio of the pores with respect to the whole of the highly dense aggregate is equal to or less than 20%, and a volume ratio of the pores communicating with an apparent outer surface of the highly dense aggregate with respect to a volume of all of the pores of the highly dense aggregate is equal to or higher than 65%.

Abstract: Provided is an air-permeable sheet (3) to be used in a state of being interposed between a suction stage (1) and an air-impermeable substrate (4) when printing is performed by a sheet-fed method on the surface of the substrate (4) fixed by suction to the suction stage (1), the air-permeable sheet capable of printing a desired printing pattern on the surface of the substrate with high accuracy. The air-permeable sheet (3) includes a non-woven fabric layer (3b) and a support layer (3a) constituted by a woven fabric or knitted fabric.

Abstract: Provided is an air-permeable sheet (3) to be used in a state of being interposed between a suction stage (1) and an air-impermeable substrate (4) when printing is performed by a sheet-fed method on the surface of the substrate (4) fixed by suction to the suction stage (1), the air-permeable sheet capable of printing a desired printing pattern on the surface of the substrate with high accuracy. The air-permeable sheet (3) includes a non-woven fabric layer (3b) and a support layer (3a) constituted by a woven fabric or knitted fabric.

Abstract: The invention provides a process and an apparatus for producing a high quality electronic component by reducing sagging at pattern side walls, which may occur when patterns of a wiring, an electrode, etc. are printed by a screen printing process using an electroconductive paste, an insulation paste, or a semiconductor paste, and reducing a mesh mark on the patterns of a wiring, an electrode, etc., or a full solid surface film, as well as a pattern formation process, by which screen printing can be applied and double face printing can be conducted with the number of process steps less than a conventional process. A pattern is formed by that a pattern is printed on a blanket having a surface comprising polydimethylsiloxane using an electroconductive paste, an insulation paste, or a semiconductor paste by a screen printing process, and the pattern is transferred from the blanket to a printing object.

Abstract: The invention provides a process and an apparatus for producing a high quality electronic component by reducing sagging at pattern side walls, which may occur when patterns of a wiring, an electrode, etc. are printed by a screen printing process using an electroconductive paste, an insulation paste, or a semiconductor paste, and reducing a mesh mark on the patterns of a wiring, an electrode, etc., or a full solid surface film, as well as a pattern formation process, by which screen printing can be applied and double face printing can be conducted with the number of process steps less than a conventional process. A pattern is formed by that a pattern is printed on a blanket having a surface comprising polydimethylsiloxane using an electroconductive paste, an insulation paste, or a semiconductor paste by a screen printing process, and the pattern is transferred from the blanket to a printing object.

Abstract: There are provided a novel optical information recording material or medium excellent in various holographic optical information recording properties such as sensitivity, response speed, long-term storage stability, and repeatability, and a substance therefor.

Abstract: There are provided a novel optical information recording material or medium excellent in various holographic optical information recording properties such as sensitivity, response speed, long-term storage stability, and repeatability, and a substance therefor.

Abstract: Hydrogen is produced from a hydrocarbon by contacting the hydrocarbon with fine particles of a carbonaceous material having an external surface area of at least 1 m.sup.2 /g at a temperature sufficient to pyrolyze the hydrocarbon.

Abstract: A non-aromatic organic compound is converted into aromatic hydrocarbons by a process in which the non-aromatic organic compound is contacted with a diamond-like carbonaceous catalyst at a temperature of 200.degree.-1,500.degree. C. The catalyst is a carbonaceous material which does not show any peak at 2.theta. of about 25.degree. attributed to C(002) diffraction in a powder X-ray diffraction pattern thereof or which shows a peak at 2.theta. of about 25.degree. attributed to C(002) diffraction in a powder X-ray diffraction pattern thereof and has a C(002) interplanar spacing greater than 0.3440 nm.