Abstract: The object of the present invention is to provide a color picture tube, which has a fluorescent film of a red emission component exhibiting a red emission with a deep color tone and is excellent in emission brightness. This object can effectively be accomplished by a color picture tube, having a face plate on which dot-shaped or stripe-shaped fluorescent films of blue, green and red emission components are respectively formed, characterized in that the fluorescent film of the red emission component is formed of a red emission composition comprising a mixture of an europium activated rare earth element oxide phosphor having an x value of 0.630 to 0.652 in CIE Chromaticity Representation and an europium activated rare earth element oxysulfide phosphor having an x value of 0.652 to 0.674 in CIE Chromaticity Representation, the red composition having an x of 0.647 to 0.662 in CIE Chromaticity Representation.

Abstract: A rare earth oxysulfide phosphor of the formula (Ln.sub.1-x-y La.sub.x Ln'.sub.y).sub.2 O.sub.2 S wherein Ln is at least one element selected from the group consisting of Y, Gd, Sc and Lu, Ln' is at least one element selected from the group consisting of Eu, Tb, Sm, Er, Tm, Dy, Ho, Nd and Pr, and x and y are numbers within ranges of 0.005<x.ltoreq.0.07 and 0.0001.ltoreq.y.ltoreq.0.2, respectively.

Abstract: A color cathode-ray tube having a fluorescent screen of red-, blue- and green-emitting phosphors as image elements of a fluorescent layer, wherein at least one of said phosphors is coated with a double oxide of zinc and aluminum.

Abstract: A color cathode-ray tube having a fluorescent screen of red-, blue- and green-emitting phosphors as image elements of a fluorescent layer, wherein at least one of said phosphors is coated with a double oxide of zinc and aluminum.

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: A method for treating a phosphor, which comprises treating a phosphor with an aqueous reagent solution comprising a chelating agent, an oxidizing agent and an alkali agent.

Abstract: A phosphor comprising a phosphor and zinc oxide formed in a suspension of the phosphor and attached to the surface of the phosphor.

Abstract: A phosphor comprising a phosphor and zinc oxide formed in a suspension of the phosphor and attached to the surface of the phosphor.

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.