Ngk Insulators, Inc.

Corning Incorporated

Takashi Harada

Fumio Abe

Toshiyuki Hamanaka

Hiroshige Mizuno

Shuichi Ichikawa

Tsuneaki Ohashi

Seiichi Asami

Yukio Miyairi

Naomi Noda

Kunikazu Hamaguchi

Aiko Otsuka

Yoshinori Yamamoto

Fumio Hattori

Yoshiyuki Kasai

Naoshi Masukawa

Kaname Fukao

Shinji Kawasaki

Raja Rao Wusirika

Takahiro Tomita

Keiichiro Watanabe

Nobuo Tsuno

Toshihiko Hijikata

Yukinari Shibagaki

Junichi Suzuki

Koichi Ikeshima

Kevin Robert Brundage

Tomoharu Kondo

Toshikazu Ito

Yukihisa Wada

Srinivas H Swaroop

David S Weiss

Masato Ogawa

Osamu Horikawa

Jun Fujita

David F Thompson

Isao Mizutani

Shunichi Yamada

Akito Higuchi

Tsuneaki Ohhashi

Noboru Kondo

Abe Fumio

Yoshihiro Fujiwara

Yuichiro Tabuchi

A ceramic honeycomb structure body () including a configuration in which a plurality of porous honeycomb segments () are bound one another with an adhesive layer () interposed between each two neighboring porous honeycomb segments (), where a plurality of protrusion portions () fixed to one of the adhesion surfaces () respectively of two honeycomb segments () opposed to each other with the adhesive layer () interposed between the two honeycomb segments () are embedded into the adhesive layer ().

Ceramic honeycomb structure body and method of manufacturing the same

This is directed to a honeycomb structure () including two or more honeycomb segments () having numerous through channels having been partitioned by walls and penetrating in axial direction thereof, the walls for through channels having a filtering function, and one end being clogged at predetermined through channels, and the other end at the remaining ones, and joint layers () for joining two or more honeycomb segments () each other. It may satisfy at least either that the Young's modulus of material of the joint layer () is 20% or less of that of the honeycomb segment (), or that the material strength of joint layer () is lower than that of the honeycomb segment (). This honeycomb structure shows a less thermal stress during use, has such a durability that no crack is formed, hardly shows a difference in temperature between the central portion and outer peripheral portion, and shows a lower pressure loss of fluid.

Honeycomb structure

A catalyst body comprising a carrier and a catalyst layer containing an alkali metal and/or an alkaline earth metal, loaded on the carrier, which catalyst further contains a substance capable of reacting with the alkali metal and/or the alkaline earth metal, dominating over the reaction between the main components of the carrier and the alkali metal and/or the alkaline earth metal. With this catalyst body, the deterioration of the carrier by the alkali metal and/or the alkaline earth metal is prevented; therefore, the catalyst body can be used over a long period of time.

Catalyst body

A method of manufacturing a honeycomb structure. (1) Water is added to silicon carbide particles and kneaded into a kneaded raw material. The silicon carbide particles have an average particle diameter of not less than 2 &#x3bc;m and not more than the honeycomb rib thickness&#xd7;0.23 and a logarithmic standard deviation of the particle size distribution of not less than 0.15 and not more than 0.40 (step S). (2) The kneaded raw material is extruded by extrusion into a honeycomb extruded body (step S). (3) The extruded body is dried (step S), calcined (step S), and fired (step S).

Method of manufacturing honeycomb structure and silicon carbide particle for manufacturing the same

A honeycomb structure that is a plurality of honeycomb segments () bonded into one piece by a bonding material (), the honeycomb segments () each having a large number of through-channels () separated from each other by partition walls (), the bonding material () being composed of components substantially the same as components composing the unified body of honeycomb segments (), and the honeycomb segments () being bonded to each other at their planes substantially parallel to the direction of channels of through- channels (), in which honeycomb structure each bonded plane () of each honeycomb segment () has a structure possessing an unbonded area () containing at least an edge portion opening to a periphery of its gas inlet side end face () and/or a periphery of its gas outlet side end face (). With this honeycomb structure, there is no cracking caused by the thermal stress during the use, and excellent durability can be obtained.

Honeycomb structure, honeycomb filter and processes for the production thereof

A method for producing a porous ceramic article involves a step of kneading raw materials including a raw material for a ceramic and a processing aid, to prepare a body, a step of forming the body, to prepare a ceramic formed product, a step of drying the formed product, to prepare a ceramic dried article, and a step of firing the ceramic dried article, to preparing a porous ceramic article, characterized in that the processing aid is a starch having been subjected to a crosslinking treatment or a material comprising a starch having been subjected to a crosslinking treatment and a foamed resin. The method allows the production of a porous ceramic article which is suppressed in the deformation during drying and is excellent in dimensional accuracy.

Method for producing porous ceramic article

There is disclosed a honeycomb structure in which a positional deviation is not easily occurred by vibration or the like in the honeycomb structure held in a can, of which the strength reduction is small and which can be easily produced, and a process for production of the structure. The honeycomb structurecomprises a cell structure portionconstituted of partition wallsarranged so as to form a plurality of cellsextending through an axial direction, and an outer peripheral walldisposed in an outer periphery of the cell structure portionA surface roughness Ra of an outer peripheral surface of the outer peripheral wall is 1 to 80 &#x3bc;m.

Honeycomb structure and process for production thereof

A silicon carbide-based porous material containing silicon carbide particles () as an aggregate and metallic silicon (), wherein the average particle diameter of the silicon carbide-based porous material is at least 0.25 time the average particle diameter of the silicon carbide particles (), or the contact angle between the silicon carbide particles () and the metallic silicon () is acute, or a large number of secondary texture particles each formed by contact of at least four silicon carbide particles () with one metallic silicon () are bonded to each other to form a porous structure. This silicon carbide-based porous material can be sintered, in its production, at a relatively low firing temperature and, therefore, can be provided at a low production cost, at a high yield and at a low product cost.

Silicon carbide-based porous material and process for production thereof

A honeycomb structurehas a large number of through-holesdivided by partition wallsand extending in the axial direction, characterized in that the honeycomb structure contains a Si phase having a lattice constant controlled at 0.54302 to 0.54311 nm at room temperature. A process for producing the honeycomb structure, includes a firing step of firing a precursor of honeycomb structure, wherein the precursor contains a Si phase and the firing step is conducted using a furnace material free from any boron-containing compound. A process for producing the honeycomb structure, includes a firing step of firing a precursor of honeycomb structure, wherein a reduction percentage of Si content in Si phase after firing step relative to Si content in Si phase before firing step is suppressed at 10% by mass or less. Having an improved thermal conductivity, the honeycomb structure is superior in thermal shock resistance.

Si-containing honeycomb structure and process for production thereof

A honeycomb filter for exhaust gas purification, possessing a honeycomb structure () having a plurality of through-holes which are separated from each other by porous partition walls and plugged alternately at the exhaust gas inlet face () and the exhaust gas outlet face (), wherein the honeycomb structure () has a slit () possessing an opening at least at the exhaust gas inlet face (), and the slit () is partially filled with a filler () in a depth of 3 to 25 times the width () of slit from the exhaust gas inlet face () toward a flow direction () of exhaust gas and a gap () is formed inside from a portion of the slit filled with the filler (). This honeycomb filter for exhaust gas purification has high purification ability, yet possesses high thermal shock resistance, and can be used continuously over a long period.

Honeycomb filter for exhaust gas purification

A honeycomb structure () having a large number of through-holes () formed in the axial direction and defined by partition walls, wherein slits () are formed so as to be exposed to at least part of the outer surface () of the honeycomb structure along the axial direction. In this honeycomb structure, each portion can deform freely without being restricted by other portion even when an uneven temperature distribution appears therein; as a result, reduction in thermal stress is possible and generation of cracks can be prevented.

A honeycomb filter is composed mainly of silicon carbide or of metallic silicon and silicon carbide; the filter being formed by bonding a plurality of honeycomb segments each of which has a plurality of through-holes being partitioned by porous partition walls. The filter is plugged alternately at the exhaust gas inlet face and exhaust gas outlet face of honeycomb segments. Each two adjacent honeycomb segments are contacted with each other at each a portion of their sides facing each other. They are bonded with each other at least at part of each portion of said sides other than the contacted portion through a bonding material having a strength lower than that of a basal body of honeycomb segment. Thus, the thermal stresses generated among the respective portions constituting the filter is reduced. The generation of cracks, etc. can be also prevented considerably.

Honeycomb filter and process for production thereof

A honeycomb structure having, in the axial direction, a number of through-channels separated by partition walls, which honeycomb structure contains refractory particles and a vitreous component and is porous. Although the honeycomb structure contains refractory particles such as silicon carbide particles or the like, it can be produced at a relatively low firing temperature; therefore, the honeycomb structure has a low production cost and a high yield and can be provided at a low price.

A ceramic honeycomb structure has an open frontal area of 50% to 85%, a porosity of 0.1% to 10%, and a proportion of the volume of pores of 1 &mgr;m or larger in diameter, in total pore volume, of 20% or more; a regenerative thermal oxidizer using the ceramic honeycomb structure. The ceramic honeycomb structure has a small porosity and, therefore, has a sufficient heat accumulation capacity and hardly causes floating by gas pressure; has controlled pore diameters and, therefore, hardly shows adsorption of VOC or the like, or rupture; and has controlled contraction and, therefore, has a large GSA.

Ceramic honeycomb structure and process for production thereof

A ceramic structure obtained by combining a plurality of sintered ceramic material segments ( ) having a thermal expansion coefficient of 3.0&times;10 /&deg; C. or more and integrating them, in which ceramic structure thermal impact-relieving zones ( ) capable of releasing the thermal impact applied are provided between the segments ( ) and the widths of the thermal impact-relieving zones ( ) in the sectional direction of the ceramic structure are various. This ceramic structure is capable of sufficiently release the thermal impact applied, without significantly reducing the effective sectional area of the structure or the overall strength of the structure, and can have the universality capable of coping with various applications and various materials.

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Nagoya, Japan

Takashi Harada