Abstract: The present invention relates to a method for preparing a rare earth oxysulfide phosphor which comprises baking a mixture containing a rare earth oxide and/or a rare earth compound which becomes a rare earth oxide easily at a high temperature a sulfiding agent and a flux, wherein a rare earth oxysulfide seed is added to the mixture before baking.

Abstract: A phosphor comprising phosphor particles and a surface treating material attached or coated on the phosphor particles, wherein said surface treating material comprises zinc and a polycarboxylic acid.

Abstract: The present invention relates to an electron-beam excited display tube useful in such a display apparatus as a color cathode-ray tube. In accordance with the present invention, the content of europium as a activator for a rare earth oxysulfide fluorescent material used as the red emission component is within the range of 0.05 to 2.0 mol %, thereby providing a very bright and low cost electron-beam excited display tube without any uneven color reproduction, even when the display screen is seen from very close quarters.

Abstract: Pigment coated phosphors comprising a europium activated yttrium oxysulfide phosphor having a europium activator value within a range of 0.04 gram atom to 0.066 gram atom per 1 mol of yttrium oxysulfide having adhered thereto red colored pigment particles such as cadmium sulfoselenide pigment particles, rouge pigment particles or red lead pigment particles, in respective amounts of 0.1 to 2.0 wt %, 0.05 to 2.0 wt % or 0.1 to 12 wt %, based upon the europium activated yttrium oxysulfide phosphor; and a cathode ray tube for high contrast color television using as a red emitting phosphor at least one of the three pigment coated phosphors.

Abstract: A pigment-coated phosphor having good finish sieve passability and capable of forming a fluorescent film with excellent properties can be produced from a process characterized by:(1) the first step of adding to a water suspension of a phosphor and a pigment an anionic polymer emulsion which has a minimum film forming temperature of less than 30.degree. C.;(2) the second step of adding a cationic polymer emulsion which has a minimum film forming temperature of 30.degree. C. or lower;(3) the thrid step of adding an anionic polymer emulsion which has a minimum film forming temperature of 30.degree. C. or higher; and(4) the fourth step of making the mixture system neutral or weakly acidic.

Abstract: A pigment coated phosphor used as a green emitting phosphor for a high contrast color television cathode ray tube. A green emitting phosphor is coated with TiO.sub.2 --ZnO--CoO--NiO system pigment particles.

Abstract: On the surface of a phosphor, pigment particles are uniformly adhered by a layer of a gelatin-gum arabic mixture. A process for manufacturing such a pigment coated phosphor includes the steps of preparing an aqueous solution of gelatin and an aqueous solution of gum arabic, allowing the phosphor to disperse homogeneously into one of these aqueous solutions, allowing the pigment particles to disperse homogeneously into the other aqueous solution, and mixing the so obtained phosphor and pigment dispersions.

Abstract: Liquid crystalline p-cyanocinnamic acid p'-n-alkoxyphenyl esters, and nematic liquid crystal compositions containing the same, useful for electro-optical devices, are described.

Abstract: Nematic liquid crystal compositions having positive dielectric anisotropy are obtained by mixing at least one of p-n-alkylphenyl-p'-cyanobenzoates represented by the formula, ##STR1## wherein R.sub.2 is n-alkyl group of 3 to 8 carbon atoms with at least one of p-cyanophenyl-p'-n-alkylbenzoates represented by the formula, ##STR2## wherein R.sub.1 is n-alkyl group of 4 to 8 carbon atoms. Said compositions exhibit nematic liquid crystal phase over a broad temperature range and therefore, are useful for the torsion effect-type display device.