Abstract: In the structure of the present invention, there can be provided a cathode ray tube in which deviation in the trajectory of the electron beams by the leakage magnetic field from the mask frame (1) is decreased by using a polygonal mask frame (1) in which the relative magnetic permeability of longer side members (31) out of two side members adjacent to each other at the joint portion of the mask frame (1) is the same as or larger than the relative magnetic permeability of the other side members (21). Thus, the significance of the present invention in industrial terms is large.

Abstract: A method of manufacturing a heater comprises: (a) washing alumina particles with warm running-water of at least 40° C.; (b) preparing a suspension for electrodeposition by suspending the washed alumina particles in a predetermined liquid; and (c) forming an alumina insulating layer made of the alumina particles on a metal wire as a heater base metal provided inside a cathode of an electron gun by electrophoresis using the suspension for electrodeposition.

Abstract: In an indirectly heated cathode comprising a heater having an alumina electrical insulating layer formed by layering and sintering alumina particles on a surface of a metal wire and an electron-emitting part that receives heat from the heater and emits thermoelectrons, and a cathode-ray tube comprising the indirectly heated cathode, the alumina particles contained in the alumina electrical insulating layer have a purity of at least 99.7 wt % and the alumina particles used for forming the alumina electrical insulating layer have a Na content of 20 ppm or less or a Si content of 100 ppm or less, thus enabling stable production, avoiding the occurrence of cracks in the alumina electrical insulating layer and heater deformation even in the practical operation of the cathode-ray tube, and lengthening the life of the heater.

Abstract: A cathode for an electron tube is described that has little deterioration of emission current after long operation, is used as a long-life oxide cathode even with high current density in a CRT, and is economical. An emissive material is adhered onto a substrate that is positioned at one opening of a cylindrical sleeve having a built-in heater coil and that includes nickel as a main component by thermally decomposing carbonate including an alkaline earth metal oxide and at least one element selected from the group consisting of titanium, nickel, zirconium, vanadium, niobium and tantalum.

Abstract: An electron gun is provided, in which a capacitance between a cathode and other electrodes, especially a control electrode is reduced largely without substantially changing a structure for supporting the cathode with an insulator. The cathode of this electron gun is disposed inside of the cylindrical metal shell. The cathode and the cylindrical metal shell are connected by three metal tabs. The cylindrical metal shell fits into a hole formed in the center portion of the insulator, and a metal outer frame is attached to the periphery of the insulator. The metal outer frame is welded to the inner surface of a cathode metal support. There is a control electrode facing the electron emitting surface of the cathode at a predetermined distance. Plural electrodes including an accelerating electrode are disposed in turn beyond the control electrode.

Abstract: A method of making a construction material luminous in response to ultraviolet rays. An inorganic material containing an ultraviolet luminous substance can be used as pigment after formed into gravelish, sandy or fragmentary material and, thus, a sufficient amount of luminance thereof can be ensured over long years while being prevented from deterioration with time of pigment. In particular, when using as inorganic materials ores containing ultraviolet luminous substance which is obtainable at a low price, pigment can be prepared at a low cost and patterned and decorated construction materials can also be manufactured at a low cost. Further, with the use of a large number of small pieces containing ultraviolet luminous substances as a pattern composing pieces, patterns complicated in shape and various in color can easily be produced on the surface of a construction material.

Abstract: A method for producing concrete products provided with inlaid patterns includes (a) preparing a reusable mold provided with recessed patterns by applying ultra violet rays on the surface of an ultra-violet-ray setting resin plate, (b) preparing a waste mold provided with recessed patterns from the reusable mold, the waste mold being made of a soluble material which can be dissolved by water, solution or heat, (c) casting concrete into the waste mold and solidifying the concrete to provide a concrete block on the waste mold, (d) dissolving and removing the waste mold from the concrete block and providing recessed patterns on the surface of the concrete block, (e) filling a coloring material into the recessed patterns on the surface of the concrete block and solidifying the coloring material, and (f) grinding the surface of the concrete block to produce concrete products provided with inlaid patterns on the surface thereof.

Abstract: The present invention discloses a fitting structure of a safety lamp to a wheel especially of a bicycle or motorcycle. Such safety lamp is replaceably mounted on an air valve disposed on the wheel. Due to such construction, people can clearly recognize the presence of the bicycle or motorcycle even from the back or the side, thus enhancing the safety of the rider. Furthermore, the safety lamp can be fitted easily and reliably by utilizing the male screw portion of the air valve of the wheel. The fitting structure includes a skirt which protects the air valve.

Abstract: A method for producing sulfur plates comprises producing an aqueous mixture by mixing and agitating sulfur powder, inorganic powder, fibers and water, filtering the aqueous mixture to form plates, molding the plates while dewatering, curing and drying the plates, and heating the plates at a temperature higher than the melting point of the sulfur. The sulfur plates attain a desired strength in a short time and are free from any cracks and have an excellent acid resistance.