Ngk Insulators, Inc.

Yasushi Noguchi

Hiroyuki Suenobu

Kyoko Makino

Atsushi Kaneda

Takehiko Watanabe

Hideaki Nishi

Yukari Nakane

Takayuki Inoue

Tomoo Nakamura

Toshio Yamada

Yukihito Ichikawa

Shinichi Miwa

Toshiyuki Hamanaka

Kazuhiko Kumazawa

Yukihisa Wada

Yoshiro Ono

Kaname Fukao

Ryuta Kono

Yukio Miyairi

Takahiro Tomita

Shuichi Ichikawa

Kenji Morimoto

Naomi Noda

Yasushi Kato

Yoshimasa Omiya

Hirotake Yamada

Takeshi Tokunaga

Toshikazu Ito

Wataru Kotani

Masato Ogawa

Tatsuyuki Kuki

Kaori Takahashi

Yohei Ono

Yukio Mizuno

Aiko Otsuka

Shinzou Hayashi

Yumi Toda

Masashi Marada

Mariko Kakitani

Yumi Muroi

Masashi Harada

Mariko Kusabe

Chika Saito

Syogo Hirose

A process for producing a honeycomb structure includes: a mixing step where forming raw materials including a ceramic raw material are mixed to obtain a forming blended material, a kneading step where the forming blended material is kneaded to obtain kneaded clay, a forming step where the kneaded clay is formed into a honeycomb shape to obtain a honeycomb formed article, and a firing step where the honeycomb formed article is fired to obtain a honeycomb structure. The ceramic raw material is a cordierite forming raw material, and a magnetic powder contained in the kneaded clay is at a ratio of 400 ppm or less with respect to solid content conversion mass of the whole kneaded clay. There is provided a honeycomb structure capable of improving trapping efficiency, in particular, initial trapping efficiency by reducing the number of coarse pores in the partition walls.

Process for producing honeycomb structure

A honeycomb structure includes: a honeycomb structural portion having porous partition walls functioning as fluid passages and separating and forming a plurality of cells extending from one end face to the other end face. The partition walls and the outer peripheral wall contain silicon carbide particles as a framework and silicon as a binder for binding the silicon carbide particles. The honeycomb structure has a partition walls thickness of 50 to 200 &#x3bc;m, a cell density of 40 to 150 cells/cm, and an average particle diameter of the silicon carbide as a framework of 3 to 40 &#x3bc;m. The honeycomb structural portion has a volume resistivity of 1 to 40 &#x3a9;cm at 400&#xb0; C., and the volume resistivity of the electrode portion at 400&#xb0; C. is not more than 40% of the volume resistivity of the honeycomb structural portion at 400&#xb0; C.

Honeycomb structure

There is provided a ceramic honeycomb structure usable as a catalyst substrate and being improved warm-up properties and thermal insulation properties, and being excellent in exhaust gas purification performance; by employing larger heat capacity and larger thermal conductivity compared with a material of the partition walls in at least one of insides and surfaces of the respective partition walls.

Ceramic honeycomb structure

A method of manufacturing a cordierite-based honeycomb structure, comprising: adding an alumina source material, a silica source material and a magnesia source material to obtain a cordierite forming material; obtaining a clay by use of the resultant cordierite forming material; extruding the resultant clay into a honeycomb shape to obtain a formed honeycomb body; drying the resultant formed honeycomb body to obtain a dried honeycomb body; and firing the resultant dried honeycomb body to manufacture the cordierite-based honeycomb structure, wherein a first alumina source material having a degree of circularity of 0.70 or more and an average particle diameter of 1 to 10 &#x3bc;m is added as at least the alumina source material in an amount of 10 mass % or more with respect to the total mass of the cordierite forming material to obtain the cordierite forming material.

Method for producing cordierite-based honeycomb structure

There is provided a method for manufacturing a ceramic honeycomb structure comprising: a coating material adjustment step for obtaining a coating material by mixing at least water with a ceramic powder aggregate having only one peak in a particle size distribution, an average particle size of 23 to 39 &#x3bc;m, and a particle size distribution width of 15 to 33, a coating material application step for applying the coating material to cover the outer periphery of a honeycomb structure having a plurality of cells separated by porous ceramic partition walls, and a coating material heat-drying step for forming an outer wall by heat-drying the coating material after the coating material application step. By the method, the outer periphery is covered with a coating material to form an outer wall to hardly generate, for example, crack generation and peeling upon drying the outer wall, and the coating material is provided.

Method for manufacturing ceramic honeycomb structure and coating material for the ceramic honeycomb structure

The honeycomb structure is provided with a honeycomb structural section, a pair of lateral electrodes on the side face of the honeycomb structural section, and at least one intermediate layer between the honeycomb structural section and the lateral electrodes. The honeycomb structural section has silicon carbide particles having an average particle diameter of 3 to 40 &#x3bc;m and silicon, and the ratio (Si/SiC) of silicon (Si) to silicon carbide (SiC) is 10/90 to 40/60. The lateral electrodes have an average particle diameter of the silicon carbide particles of 10 to 70 &#x3bc;m and a Si/SiC ratio of 20/80 to 50/50. The intermediate layer has an average particle diameter of silicon carbide particles and Si/SiC between those of the honeycomb structural section and those of the lateral electrodes. The electric resistance between the lateral electrodes of the honeycomb structural section is 2 to 100&#x3a9;.

There is disclosed a honeycomb structure including a honeycomb structure section including: porous partition walls to divide and form a plurality of cells which extend from one end surface to the other end surface and become through channels of a fluid; and an outer peripheral wall positioned in an outermost periphery. The partition walls and the outer peripheral wall contain silicon carbide particles as an aggregate, and silicon as a binder to bind the silicon carbide particles, thicknesses of the partition walls are from 50 to 200 &#x3bc;m, a cell density is from 50 to 150 cells/cm, an average particle diameter of silicon carbide as the aggregate is from 3 to 40 &#x3bc;m, and a volume resistivity at 400&#xb0; C. is from 1 to 40 &#x3a9;cm.

There is provided a manufacturing method of a honeycomb structure, comprising: forming kneaded clay containing a cordierite forming raw material formed by mixing talc having an average particle diameter of 0.1 to 40 &#x3bc;m, kaolin having an average particle diameter of 0.1 to 20 &#x3bc;m, an alumina source raw material having an average particle diameter of 0.05 to 10 &#x3bc;m, and a silica having an average particle diameter of 0.1 to 20 &#x3bc;m, a binder, a surface active agent, water, and a hygroscopic resin having an average particle diameter of two to 200 &#x3bc;m after water absorption and a water absorption magnification of two to 100 magnifications into honeycomb shape to fabricate a honeycomb formed body; and firing the honeycomb formed body to obtain a honeycomb structure whose porosity is less than 40%.

Manufacturing method of honeycomb structure

A honeycomb structureof the present invention is provided with porous partition wallsmade of a ceramic material containing cordierite as a main crystal phase and separating and forming a plurality of cellsfunctioning as fluid passages. The partition wallscontain sodium at 0.08 to 0.15 mass % in terms of sodium oxide. A honeycomb structure having a large average pore size can be provided.

Honeycomb structure and method for manufacturing the same

A honeycomb filter including partition walls having a porous partition wall base material and a surface layer provided on only inflow side or both inflow and outflow sides of the partition wall base material, and satisfying the following conditions capable of using as a DPF. The surface layer has a peak pore diameter of from 0.3 &#x3bc;m to 20 &#x3bc;m (exclusive) being equal to or smaller than the average pore diameter of the base material; the porosity of from 60% to 95% (exclusive) when measured by mercury porosimetry being larger than that of the base material; and the thickness Lof from 0.5% to 30% (exclusive) of the partition wall thickness L; and mass per filtration area of from 0.01 mg/cmto 6 mg/cm(exclusive). The base material has an average pore diameter of from 10 &#x3bc;m to 60 &#x3bc;m (exclusive) and a porosity of from 40% to 65% (exclusive).

Honeycomb filter

A method of producing a honeycomb structure includes producing a honeycomb structure using methyl cellulose as at least part of a binder, the methyl cellulose having a weight average molecular weight (Mw) of 4,000,000 to 5,000,000, and having an integral molecular weight distribution value of components having a molecular weight of 100,000 or less in the integral molecular weight distribution curve of 15 or less.

Method of producing honeycomb structure

A method for producing an aluminum titanate ceramic, which comprises subjecting, to forming, a raw material for aluminum titanate formation, containing NaO-containing &#x3b1;-alumina particles, to obtain a formed body and then firing the body, wherein the &#x3b1;-alumina particles has such a crystal structure that the ratio of the average value of the average length in axis a direction and the average length in axis b direction, to the average length H in axis c direction is 3 or more.

Method for producing aluminum titanate ceramic

There is disclosed a ceramic structure which comprises a material having a controlled pore distribution and including cordierite as the main crystal phase. In the pore distribution, the volume of pores having pore diameters smaller than 20 &#x3bc;m accounts for 15% or less of the total pore volume, and the volume of pores having pore diameters of 20 to 100 &#x3bc;m accounts for 70% or more of the total pore volume. This ceramic structure is suitable for realizing a ceramic catalyst body which has excellent purification efficiency, is reduced in pressure loss, and is mountable even in a limited space.

Ceramic structure and process for producing the same

A method for producing a honeycomb structure is provided, where a body containing a forming formulation composed of a cordierite forming material and an organic binder is formed into a honeycomb shape to prepare a honeycomb shaped article, and the honeycomb shaped article is fired to obtain a honeycomb structure. The forming formulation includes two or more types of magnesium-containing materials containing at least talc, and a magnesium-containing material except talc has an average particle diameter of 4 &#x3bc;m or less.

Method for producing honeycomb structure and honeycomb structure

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Nagoya, Japan

Yasushi Noguchi