Abstract: An optical recording medium is disclosed, which has a substrate and a recording film formed on the substrate. The recording film has a film comprising tin as the main component and passive state-forming metal layers formed on both sides of the tin film. The optical recording medium has a high recording sensitivity, a good signal quality and a high reliability. The optical recording medium is prepared by forming a first passive state-forming metal layer, a film comprising tin as the main component and a second passive state-forming metal layer in sequence on a substrate, and preferably heating the thus-obtained laminate.

Abstract: A disk substrate is supported by a support base formed on a center pin which is vertically movable on a selective basis, a table is set below the disk substrate, and a stamper is positioned on the table by means of a guide ring or the like. A ring-shaped portion of resin which is cured upon radiation of ultraviolet rays is set on the stamper. The center pin is then caused to descend by means of a drive mechanism, to a first position, at which position the disk substrate is on the point of contact with the resin. Then, the disk substrate is caused to descend intermittently in units of very small amounts, to a second position, at which position the entire periphery of the ring-like resin is brought into contact with the disk substrate.

Abstract: An optical recording medium composed of an energy-absorbing layer having a high energy absorption with respect to light having a wavelength of 750 to 850 nm, the energy-absorbing layer being a film composed of a matrix of a metal oxide and fine particles of a metal dispersed in the matrix, and an energy-sensitive layer which is a film or sheet of an organic material in contact with at least one surface of the energy-absorbing layer.

Abstract: An oil-containing waste water treating material, comprising an active carbon upon whose surface is chemically bonded at least one nitrogenous compound which is an amine or a quaternarized derivative thereof.

Abstract: An inorganic ion exchanger prepared by kneading a blend of anatase type titanic acid or amorphous titanic acid with sulfuric acid, hydrochloric acid or phosphoric acid and water, extrusion molding the blend, and thereafter, heat treating the extruded product at an elevated temperature. The inorganic ion exchanger has high strength in water and is suitable for use in the removal or the concentration and recovery of injurious or beneficial materials contained in water.