Matsushita Electric Industrial Co., Ltd.

Yasuo Wakahata

Iwao Ueno

Akihiro Takami

Kimio Kobayashi

Kaori Okamoto

Hideyuki Okinaka

Hideaki Tokunaga

Kaori Shiraishi

Toru Fukada

Atsushi Nishino

Kiyotaka Wasa

Masahiro Nagasawa

Shinji Harada

Hideki Matsukawa

Hiroshi Kawarada

Toshio Tatsumichi

Keiichi Noi

Fumio Hosomi

Masahiro Itoh

Takeshi Masuyama

Naoki Mutoh

Kensuke Kuchiba

Miho Higashitani

Youichi Ogoshi

Yoichi Ogoshi

Kunio Nishi

Hiroshi Abe

Mitsuyoshi Hamanaka

Tamotsu Kajitani

Masazumi Katase

Tomohiro Yashiki

Minoru Hirota

A method for manufacturing varistor by which a varistor having a high plating resistance and a high moisture resistance is manufactured by selectively forming a compact high-resistance layer having a uniform thickness on the surface of a varistor element. In the method, the varistor element (,) is first formed by alternately laminating ceramic sheets (,) mainly of a zinc oxide and internal electrodes (,) upon one another, and then, Ag electrode paste which becomes external electrodes (,) is applied to both end faces of the element (,). Then, after the element (,) is sintered through heat treatment, the element (,) is buried in SiO,or a mixture (,) containing SiO,and the element (,) is heat-treated for 5-10 minutes at 600-950&deg; C. in the air or in an oxygen atmosphere.

Method for manufacturing varistor

The electronic component of the present invention includes: an element having an internal electrode therein; an external electrode formed on an end portion of the element where an end face of the internal electrode is exposed; and a protection layer formed on the entire surface of the element except for the end portion of the element, wherein the protection layer is made of a metal oxide.

Electronic component and method for fabricating the same

A furnace for manufacturing ceramics is disclosed. The furnace contains a cylindrical heat resistant container, a furnace body for heating the cylindrical heat resistant container, and driving means for driving the cylindrical heat resistant container. The cylindrical heat resistant container rotates about a central shaft. At the same time, a first end and alternately a second end of the cylindrical heat resistant container are raised and lowered periodically, thus creating a seesaw motion while any material contained in the cylindrical heat resistant container is fired by the furnace body.

Furnace and method for firing ceramics

The invention is directed to a method of firing ceramics and a furnace for manufacturing ceramics. Ceramic forms are first fired in a cylindrical heat resistant container in a furnace core tube by using a lateral tubular furnace to increase their mechanical strength. Then, the container is rotated while the ceramic forms are fired further in a predetermined temperature region, which includes a maximum temperature. In this manner the ceramic forms are heated in a uniform state, both thermally and atmospherically, while receiving moderate impact by rotation, and defective appearance and fluctuations in the characteristics of the ceramics are suppressed. In particular, the container is rotated within a temperature region which is higher than the temperature used to start increasing the mechanical strength of the ceramic forms. Further, the ceramic forms can be packed into the container at a higher rate during the rotation portion of the process than during the first firing.

Method for firing ceramic forms

The varistor element contains zinc-oxide as a main constituent and at least bismuth and antimony as accessory constituents. The content of bismuth in the form of Bi.sub.2 O.sub.3 is in a range from about 0.1 to 4.0 mol % and the content of antimony in the form of Sb.sub.2 O.sub.3 constitutes a mol-ratio of Sb.sub.2 O.sub.3 /Bi.sub.2 O.sub.3 less than or equal to about 1.0 mol %. These materials are mixed thoroughly and are pressed into a compact. After coating both sides of the compact with Ag or Ag--Pd paste, the compact and its electrodes are sintered simultaneously at a temperature of about 800.degree. C. to 960.degree. C.

Varistor formed of bismuth and antimony and method of manufacturing same

Method for producing ceramic parts

A method for manufacturing semiconductor-type laminated ceramic capacitors with a grain boundary-insulated structure including the steps of calcinating starting material of mixed powder in air or in nitrogen atmosphere after grinding, mixing and drying the mixed powder; forming raw sheets; printing a pattern of inner electrode paste on the surface of the raw sheets; calcinating the laminated body in air; sintering the laminated raw sheets in reducing atmosphere or in nitrogen atmosphere after calcination; re-oxidizing in air after sintering; and covering the edges of sintered ceramic sheets with outer electrode paste and baking after re-oxidation, terminals of inner electrodes being exposed to the edges, wherein: the starting material of mixed powder comprises a material of the composition Sr.sub.(1-x) Ba.sub.x TiO.sub.3 containing excess Ti to make a final molecular ratio of Ti to Sr.sub.(1-x) Ba.sub.x in the range of 0.95.ltoreq. Sr.sub.(1-x)Ba.sub.x /Ti&lt; 1.00 (where x is in the range of 0&lt; x.ltoreq. 0.3); a first component of at least one or more kinds of the compounds selected from Nb.sub.2 O.sub.5, Ta.sub.2 O.sub.5, V.sub.2 O.sub.5, W.sub.2 O.sub.5, Dy.sub.2 O.sub.5, Nd.sub.2 O.sub.3, Y.sub.2 O.sub.3, La.sub.2 O.sub.3, or CeO.sub.2 ; a second component of Mn and Si converted into MnO.sub.2 and SiO.sub.2 respectively; and an optional third component of at least one or more kinds of the compounds selected from Na.sub.2 SiO.sub.3, NaAlO.sub.2, Li.sub.2 SiO.sub. 3, LiAlO.sub.2, and Al.sub.2 O.sub.3.

Ceramic capacitor with a grain boundary-insulated structure

Semiconductor-type laminated ceramic capacitor with a grain

A laminated semiconductor ceramic capacitor with a grain boundary-insulated structure comprises a semiconductor ceramic block with a grain boundary-insulated structure, a plurality of Ni inner electrodes and outer electrodes, wherein the Ni inner electrodes are obtained from a paste containing a powder prepared by solubilizing at least one compound containing an atom selected from the group consisting of Li, Na and K into Ni or an Ni containing compound; the Ni inner electrodes are placed in a substantially parallel manner within the ceramic block to reach to the corresponding opposite edges of the ceramic block alternatively one by one; and the outer electrodes are electrically connected to the corresponding edges of the inner electrodes, respectively.

Laminated semiconductor ceramic capacitor with a grain

A large number of liquid crystal display devices is formed on a single plane, each of the liquid crystal display devices being formed by arranging liquid crystal between transparent substrates which allow light from a light source to pass through. Display portions of the respective liquid crystal display devices are covered by a masking member (23) and a light guide which is formed of light guide devices, one or more of which being provided for each of said liquid crystal display devices, and junctions between the liquid crystal display devices are also covered by the light guide. With this structure, when the light guides are formed such that the junctions between the plurality of liquid crystal display devices are also covered, lattice-like non-display lines do not appear, thereby providing substantially visually uniform brightness throughout the entire screen of the large-sized liquid crystal display and improving the entire image.

Large-sized liquid crystal display

The present invention provides a liquid crystal color display panel of improved positive contrast by utilizing the so-called Guest-Host effect.

Liquid crystal color display panel

Growing community of inventors

Katano, Japan

Yasuo Wakahata