Abstract: Provided is a method for preparing alkali cellulose having alkali distributed uniformly therein. A uniform alkali distribution in the alkali cellulose makes it possible to prepare cellulose ether which has been substituted uniformly in an etherification reaction step. The resulting cellulose ether does not contain a floating water-insoluble portion which will otherwise appear owing to insufficient substitution. More specifically, provided are a method for preparing alkali cellulose, comprising simultaneously feeding pulp powder and an aqueous alkali solution to a high speed disperser to continuously bring them into contact with each other and a method for preparing cellulose ether, comprising reacting the resulting alkali cellulose with an etherifying agent.

Abstract: A water-soluble cellulose ether is separated from its suspension by passing a suspension of water-soluble cellulose ether particles in water through a filter of perforated metallic or ceramic filter medium under pressure, removing the filter cake of water-soluble cellulose ether from the filter medium, and cleaning the filter medium with steam, compressed air or water under pressure. The invention enables to separate a water-soluble cellulose ether, especially having a high dissolution temperature, avoids the filter from being clogged, and extends the operative time of the filter.

Abstract: The present invention is to solve the problems caused by a conventional method for producing a zinc chloride-loaded support wherein zinc chloride is adsorbed on a solid support in an aqueous solution of zinc chloride. The problems include environmental destruction caused by the treatment of a used aqueous solution of zinc chloride, corrosion to a reactor, a threat to health for workers, deterioration of zinc chloride due to deliquescence thereof, and reduction of specific surface area.

Abstract: Pulp is ground by means of a vertical roller mill. The average particle diameter of the resulting powdered pulp is adjusted to 20-300 ?m. The powdered pulp thus obtained is used as a starting material for the production of cellulose ethers.

Abstract: The present invention is to solve the problems caused by a conventional method for producing a zinc chloride-loaded support wherein zinc chloride is adsorbed on a solid support in an aqueous solution of zinc chloride. The problems include environmental destruction caused by the treatment of a used aqueous solution of zinc chloride, corrosion to a reactor, a threat to health for workers, deterioration of zinc chloride due to deliquescence thereof, and reduction of specific surface area.

Abstract: A high pressure discharge lamp in which, in the silica glass which comprises the hermetically sealed portion on the cathode side, fractures originating from the contact area with the cathode are prevented from propagating as in a high pressure discharge lamp of the direct current operating type which has: a discharge vessel of silica glass in which opposite sides an arc tube portion are each joined to a respective hermetically sealed portion; a metal foil is located in each of the hermetically sealed portions; a supply lead is attached in each the hermetically sealed portion with an inner end of the supply lead being connected to a respective one of the metal foils and an outer end projecting outwardly from the discharge vessel; an anode and a cathode are each attached in one of the hermetically sealed portions and have a base which is connected to one of the metal foils and a tip which projects into the arc tube portion; by the outer surface of the cathode-side hermetically sealed portion being surrounded by

Abstract: A metal halide lamp with a distance of less than 3.0 mm between the electrodes, in which in the hermetically sealed portion no cracks occur, which can be produced without difficulty, and which enables advantageous operation is achieved with a halide lamp in which an arc tube made of quartz glass contains a cathode and an anode spaced from each other at a distance of less than or equal to 2.9 mm together with mercury and metal halides, and which is operated with a nominal wattage range of from 100 to 400 W using direct current, by causing the ratio D/H to be greater than or equal to 1.9 when D is the maximum inside diameter in millimeters in a direction which orthogonally intersects the axial direction of the electrodes in the discharge space and H is the length of the cathode projecting within the discharge space, also in millimeters.

Abstract: A metal halide lamp in which no color shadowing occurs on the light acceptance surface and which at the same time emits with sufficient brightness is achieved according to the invention by encapsulating lutetium halide and one or more of the metal halides from groups A, B and C in an arc tube of a metal halide lamp together with a mercury halide:Group A: dysprosium halide, holmium halide, erbium halide, thulium halideGroup B: cerium halide, praseodymium halide, neodymium halideGroup C: cesium halide.

Abstract: A lamp device having one-piece arrangement of a metal halide lamp and a reflector which has a front cover in which a small, compact shape for installation of a halogen lamp can be obtained, which has characteristics of high efficiency, good color reproduction and high power. The lamp has a unidirectional base and a unidirectional sealed end which is configured such that it is surrounded by a front cover and a reflector.

Abstract: A reflector used for a light source material of a liquid crystal video projector provides a good projection image and causes no color shading to occur in the periphery of a screen. The reflector has a surface on which a dielectric multifilm coating is deposited. The reflector reflects only visible light beams and has a wavelength .lambda..sub.1, which has a spectral transmittance on a short wave side (with normal incidence) of 20% and is equal to or smaller than 440 nm and, at the same time, has a wavelength .lambda..sub.2, which has a spectral transmittance on a long wave side (with normal incidence) of 50% and is equal to or greater than 820 nm.

Abstract: Disclosed herein is a lighting lamp having a light-emitting tube in which lutetium (Lu), lithium (Li) and a halogen are sealed together with mercury and a rare gas. The lighting lamp satisfies the following conditions (1) and (2):(1) the proportion Li/Lu (the ratio in terms of the number of atoms of lithium to lutetium) is 0.5 to 1.5; and(2) the sealed amount of the halogen is the total of a stoichiometric amount of halogen in which the halogen form halides with lutetium and lithium to be sealed and an excess amount of 0.5.times.10.sup.-6 to 4.times.10.sup.-6 molecular mole/cc based on the internal volume of the light-emitting tube.

Abstract: A metal vapor discharge lamp includes a light-emitting tubing in which a halogen and iron at least 0.005 mg per cc of the internal volume of the light-emitting tubing are filled together with mercury and a rare gas in amounts sufficient to retain a discharge. Magnesium is additionally filled in at a magnesium-to-iron ratio of 1/40-2/3 in terms of gram atom number so as to prevent iron from depositing on the inner wall of the light-emitting tubing and forming a thin film thereon.

Abstract: A magnesium vapor discharge lamp includes a light-emitting tubing in which magnesium and a halogen are sealed as light-emitting substances together with mercury and a rare gas in amounts sufficient to retain a discharge. Iron is additionally sealed within the light-emitting tubing.

Abstract: A semiconductor wafer can be exposed by arranging a combination of electrodes in an opposed relation with an interelectrode distance of not more than 15 mm in a closed discharge cavity, enclosing, within the cavity, mercury as a light-emitting discharge component in an amount such that the vapor pressure of mercury reaches 0.4-5 atms during discharge lighting, forming a discharge between the combination of electrodes while controlling the discharge current at not less than 10 A, and irradiating light, which has been radiated as a result of the discharge and contains at least one of light components having wave-lengths of 405 nm and 436 nm respectively, onto the surface of a photoresist applied on the semiconductor wafer through a photomask or reticle and a lens which permits transmission of the light having wavelength of 405 nm or 436 nm therethrough.