Ngk Insulators, Inc.

Yohei Ono

Yuji Katsuda

Satoshi Yamazaki

Atsushi Watanabe

Yasushi Noguchi

Shuji Ueda

Takehiko Watanabe

Yasushi Uchida

The circumference coating material fills a recessed groove that is formed on a circumferential surface of a honeycomb fired body and extends an axial direction at which a part of cells are opened to the outside and to cover the circumferential surface, thereby forming a circumferential wall on the circumferential surface of a honeycomb structure, and the circumference coating material includes colloidal silica in a part of raw materials to be used and has a chlorine concentration of 150 ppm or less. In addition, the colloidal silica to be used has a chlorine concentration of 500 ppm or less, and the colloidal silica is produced using at least any one acid of sulfuric acid, phosphoric acid, and organic acid.

Circumference coating material, bonding material, honeycomb structure, and method of producing honeycomb structure

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 method for manufacturing cordierite ceramics is provided, including forming and heating a cordierite-forming raw material containing &#x3b1;-alumina. The degree of orientation, expressed by (I/(I+I), where Iis height of X-ray diffraction intensity of an hkl-face of an &#x3b1;-alumina crystal, by X-ray diffraction measurement of an &#x3b1;-alumina crystal in a formed article of the raw material for forming cordierite is 0.10 or more.

Method for manufacturing cordierite ceramics

A method of producing cordierite ceramic where the degree of stacking faults and the particle diameter of kaolinite used as a component of a cordierite-forming raw material are appropriately adjusted so that microcracks having an average width of 0.3 &#x3bc;m or more are introduced into the resulting cordierite ceramic to produce a high-quality cordierite ceramic that includes a cordierite crystal oriented in a specific direction and has a porosity of 25% or more and a coefficient of thermal expansion of 0.30&#xd7;10/&#xb0; C. or less.

Cordierite ceramic and method of producing the same

A cordierite ceramic is provided, which includes at least zirconium oxide or hafnium oxide, and also includes titanium oxide. The molar ratio of zirconium (Zr), hafnium (Hf) and titanium (Ti) in terms of the moles in the form of the dioxides, respectively which is given by the formula [(ZrO+HfO)/TiO] is in a range of 0.1 to 5. In this cordierite ceramic, the phases of the components are contained mainly as zirconium titanate or hafnium titanate, and no heterogeneity in appearance, caused by change in color and generation of spots occurs. A honeycomb structure made of the cordierite ceramic is also provided.

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Kiyosu, Japan

Yohei Ono