Kabushiki Kaisha Toshiba

Tokyo Shibaura Denki Kabushiki Kaisha

Norio Koike

Takeo Itou

Hidemi Matsuda

Kunihiro Ikari

Shigeo Takenaka

Yasuhiro Shirakawa

Takeo Ito

Masaaki Tamatani

Takeshi Takahara

Kiyoshi Tokita

Yoshinori Takahashi

Mitsuhiro Oikawa

Kazuhiko Shimizu

Shingo Watanabe

Kaneharu Kida

Masakazu Takaki

Nobuyuki Tsuda

Sakae Ajiro

Hatsuo Tsukagoshi

Seiji Sagow

Ryoichi Ogura

A dispersion solution of colloidal silica is coated on a pigment layer composing a filter layer and then dried. Thus, the state of the front surface of the filter layer (pigment layer) is controlled without affecting the filter layer (pigment layer). A phosphor layer is formed on the filter layer (pigment layer).

Method for forming phosphor screen

A color cathode ray tube having a vacuum envelope including a panel with an inner surface, a neck and a funnel connecting the neck to the panel, a phosphor screen provided on the inner surface of the panel for emitting visible light, an electron gun provided in the neck for emitting a plurality of electron beams towards the phosphor screen, a shadow mask provided adjacent to the phosphor screen with a predetermined distance from the phosphor screen, and a porous layer, which is formed on a surface of the shadow mask facing to the electron gun. The porous layer is formed by using metal alkoxide solution which contains black color pigment containing both of cobalt oxide and nickel oxide.

Color cathode ray tube having a shadow mask covered with a porous layer

According to the present invention, there is provided a method for forming a color tube phosphor screen comprising the steps of forming a light-absorbing matrix having holes on a faceplate, coating a silica colloidal solution or an alumina colloidal solution containing a multivalent metal ion in said holes and washing said holes, and forming phosphor layers of three colors in said washed holes. The color tube phosphor screen formed through the method of the present invention has no phosphor residual, especially pigment residual.

Method of forming color tube phosphor screen

A photoresist film containing a phosphate of a formalin condensate of diazodiphenylamine, 2.5-bis(4'-azide-2'-sulphobenzilidene) cyclopentanone Na, polyvinylalcohol, and polyvinylpyrrolidone is formed on the inner surface of a faceplate. The photoresist film is hardened by light exposure using a point or linear light source, which is essentially a circular light source, via a shadow mask having a large number of apertures. A light absorbing film is formed on this photoresist film. Then the hardened photoresist film and the light absorbing film on top of it are removed using a peeling agent.

Formation method and photoresist composition for phosphor screens of

A cathode ray tube has an envelope including a faceplate with a sidewall portion and a neck receiving an electron gun emitting at least one electron beam. The faceplate is coated with a phosphor layer for emitting a visible light by bombardment of the electron beam on its inner surface and is covered with an antistatic film. To prevent accumulation of electrostatic charges, the antistatic film is electrically connected to a metal tension band wound around the sidewall portion by a connecting element. The connecting element is conductive oxide layer which essentially consists of a conductive substance and a binder consisting at least amorphous silicon oxide or silicon hydroxide.

Cathode ray tube with an electrical connecting element

A photoresist film containing a phosphate of a formalin condensate of diazodiphenylamine, 2.5-bis (4'-azide-2'- sulphobenzilidene) cyclopentanone Na, polyvinylalcohol, and polyvinylpyrrolidone is formed on the inner surface of a faceplate. The photoresist film is hardened by light exposure using a point or linear light source, which is essentially a circular light source, via a shadow mask having a large number of apertures. A light absorbing film is formed on this photoresist film. Then the hardened photoresist film and the light absorbing film on top of it are removed using a peeling agent.

Method for forming light absorbing pattern using photoresist composition

In a cathode ray tube with a phosphor screen containing a Zn type green emitting phosphor, e.g. ZnS, ZnCdS and Zn.sub.2 SiO.sub.4, the surface of the phosphor particle includes a surface area of (Co,Zn)O. The surface area is green colored to operate as a filter against incident light from outside the tube and reduces background brightness of picture images caused by excitation of scattering electrons. Thus, the contrast of the picture images rises. The contrast is further increased by Ni doped.

Cathode ray tube with pigment-doped phosphor

Electron tube having an evacuated envelope equipped with an electron emitting cathode, wherein a layer of activated silicon oxide is formed inside the envelope. The activated silicon oxide layer improves the emission life.

Electron tube provided with porous silicon oxide getter

The shadow mask of a color cathode ray tube is arranged in the vicinity of a phosphor screen. The shadow mask is provided with through-holes that select the electron beams emitted from the electron guns. A layer comprising, as a filler, one or other of a metal, metal oxide, metal carbide, metal nutride, or a mixture of two or more of these, for example zirconium powder and, as a binder, one of an amorphous metal oxide compound, amorphous metal hydroxide compound or a mixture of these, for example silicon oxide, is formed on the surface of the shadow mask. This layer increases thermal radiation of the shadow mask, reduces electron scattering, and raises the residual emissivity.

Color cathode ray tube

In a color cathode ray tube provided with in-tube metallic members of which the main constituent is iron, such as the shadow mask assembly or inner shield, at least part of the surface of these metallic members is formed with a blackened region. The vicinity of the surface of this blackened region contains Al, Fe and Si, the Si content being selected in the range 1.5 wt % to 30 wt %, preferably 4 wt % to 15 wt %.

Color cathode ray tube having shadow mask with silicon

A color picture tube fitted with a phosphor screen formed of a green-emitting phosphor prepared from copper and aluminum-activated zinc sulfide, a red-emitting phosphor prepared from europium-activated yttrium oxysulfide, and a blue-emitting phosphor prepared from silver-activated zinc sulfide, and wherein the copper concentration ranges between 0.01 and 0.03% by weight and the europium concentration ranges between 5.1 and 6.1% by weight.

Color picture tube

A photoresist composition, comprising, a water-soluble azide compound and a water-soluble polymer in combination with a water-soluble silane compound having at least two alkoxysilane groups.

Photoresist composition with azide having alkoxy silane as adhesion

A projection type green cathode ray tube (CRT) with improved brightness despite an increase in the temperature of the faceplate, a method for manufacturing a phosphor screen adopted therein, and a projection video device which utilizes the projection type green CRT. The phosphor screen of the CRT is formed of a cerium-activated calcium sulfide phosphor which contains 0.01 to 0.3 mol% of cerium. According to the method for manufacturing the phosphor screen, the cerium-activated calcium sulfide phosphor is precipitated in a 0.3 to 5% aqueous solution of water glass based on weight. The aqueous solution does not contain barium ions. The projection video device includes the green CRT, a red CRT having a phosphor screen which is formed of an europium-activated yttrium oxide phosphor, and a blue CRT having a phosphor screen which is formed of a silver-activated zinc sulfide phosphor. Brightness of images is improved and does not substantially change over time.

Projection type green cathode ray tube, method for manufacturing

Photoresist compositions based upon a water-soluble polymer are disclosed together with a water-soluble bisazide compound as a cross-linker, a water-soluble adhesion-improving diazo compound are characterized in that a water-soluble silane compound is included. The compositions are photosensitive, particularly to ultraviolet rays, and adhere well to the substrates to which they are applied. The compositions of the invention are used as photoresists.

Water soluble photoresist composition with bisazide, diazo, polymer and

There are disclosed a composition for making a picture tube fluorescent screen characterized by essentially consisting of a light-sensitive resin at least having recurring units (1) and (2) represented by the formulas: ##STR1## wherein R and X.sup.- have the same meanings as defined in the specification, and CaS-based phosphor particles which are dispersed in an aqueous medium, and a method of making a picture tube fluorescent screen using the same. According to this invention, it is possible to make a picture tube exhibiting an excellent light emitting efficiency and a contrast by a simple process.

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Fukaya, Japan

Norio Koike