Abstract: A support plate for use in firing which has a main component of the crystal phase after firing being the same as that of an article to be sintered, and has a surface roughness (Ra) of the surface to be contacted with the article to be fired of 8 to 50 ?m. A firing method using the above support plate is free from the breaking or chipping of cells of a honeycomb fired article as a product and also is free from the breaking thereof during firing, the staining or cells, the cracking or deformation thereof, or the failure of reaction, which is caused by the mismatch in expansion-shrinkage behavior, and thus allows the prevention of the decrease of the yield in the production of a honeycomb fired article as a product.

Abstract: Disclosed is a method for producing a porous ceramic structure wherein as a pore-forming agent, hollow particles (microcapsules) made of an organic resin are used, and as at least one type of raw material particles, particles are used which contain 30 to 100 mass % of particles (spherical particles) having a circularity of 0.70 to 1.00 with respect to the total mass of the particles.

Abstract: A method of producing a cordierite honeycomb structure includes: preparing clay containing a cordierite raw material having an aspect ratio of 1.5 or more; forming the clay to prepare a formed product of a honeycomb shape; drying the formed product to prepare a dried honeycomb product; and firing the dried honeycomb product to prepare a cordierite honeycomb structure. The production method can obtain a cordierite honeycomb structure capable of suppressing formation of cracks during firing.

Abstract: An electric control device 70 is applied to an internal combustion engine 10 capable of a pre-mixed charge compression ignition combustion in which air-fuel mixture gas including air and fuel injected from an injector 37 is formed in a combustion chamber 25, and the air-fuel mixture gas is self-ignited to be combusted by compressing the air-fuel mixture gas during a compression stroke. The electric control device injects high pressure fluid such as air from the air injection valve 38 into the air-fuel mixture gas at a predetermined acting timing within a compression stroke prior to fuel pyrolysis starting timing to enhance the temperature un-uniformity of the air-fuel mixture gas. This enables the temperature un-uniformity of the air-fuel mixture gas at the fuel pyrolysis starting timing to become larger than the temperature un-uniformity of the air-fuel mixture gas at the fuel pyrolysis starting timing obtained only by simply compressing the air-fuel mixture gas during the compression stroke.

Abstract: There is provided a method for manufacturing a silicon carbide based honeycomb structure, the method using, as a part of a starting material, a recycled raw material recycled from a recovered material generated in a process for manufacturing the silicon carbide based honeycomb structure and derived from a starting material for a silicon carbide based honeycomb structure; wherein the recycled raw material is pulverized to have an average particle size of 10 to 300 ?m. According to the present invention, structure defects such as voids or coarse particles, which have been problems upon manufacturing a silicon carbide based honeycomb structure, are hardly formed, and a silicon carbide based honeycomb structure having excellent strength and uniform heat conductivity can be obtained. In addition, since a once kneaded material is used as a part of a starting material, the time for kneading can be shortened.

Abstract: There is provided a honeycomb structure and a method for producing the honeycomb structure, capable of reducing variance in pore diameter depending on part and capable of increasing the mean pore diameter as a whole. There is provided a method for producing a cordierite honeycomb structure 1 including the step of firing a honeycomb formed body. In the firing step, a temperature rise rate from 1200° C. to 1250° C. is controlled to 40° C./hr or more, a temperature rise rate from 1250° C. to 1300° C. is controlled to 2 to 40° C./hr, and a temperature rise rate from 1300° C. to 1400° C. is controlled to 40° C./hr or more. There is further provided a honeycomb structure having a porosity of 50 to 70%, a mean pore diameter of 15 to 30 ?m, a difference in a mean pore diameter of 5 ?m or less between in the central portion and in the outer peripheral portion, a thermal expansion coefficient of 1.0×10?6/° C.

Abstract: 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 ?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.

Abstract: A porous honeycomb structure includes: a plurality of partition walls containing cordierite as a main component and constituted of a porous ceramic having a porosity of 55 to 75% and an average pore diameter of 15 to 35 ?m, wherein the partition walls have a pore distribution represented by the following condition formula (1): Lr>0.3×P/100+0.91,??(1) “in the above condition formula (1), Lr means an average developed length ratio, and P means a porosity obtained from a total pore volume measured by a mercury press-in type porosimeter, assuming that a true specific gravity of cordierite is 2.52 g/cc.” The porous honeycomb structure is capable of effectively achieving raising of a trapping efficiency of soot or the like, lowering of a pressure loss, improving a purifying performance by effective use of a catalyst, and lengthening a trapping time, and is additionally capable of improving a dissolved loss limit at the time of filter regeneration, and an isostatic strength.

Abstract: There is disclosed a honeycomb filter capable of minimizing an initial pressure loss during an exhaust gas treatment in a state in which a high efficiency is maintained in trapping particulate matters included in an exhaust gas. In the honeycomb filter which includes porous partition walls to define and form a plurality of cells constituting channels of a fluid and in which the predetermined cells each opened at one end thereof and plugged at the other end thereof and the remaining cells each plugged at one end thereof and opened at the other end thereof are alternately arranged, an average pore diameter of the partition walls is in a range of 8 to 18 ?m, and a standard deviation in terms of common logarithm in pore diameter distribution, when pore diameters are expressed in terms of common logarithm, is in a range of 0.2 to 0.5.

Abstract: In a method for producing a honeycomb structure 20 which comprises disposing a material for forming outer wall 11 on the outer peripheral surface 3 of a cell structure 1 having a plurality of cells serving as fluid flowing channels to produce a cell structure being provided with a material for forming outer wall 10 and firing the resulting cell structure being provided with a material for forming outer wall 10, wherein a cell structure being provided with a material for forming outer wall 10 in which the absolute value of the difference between the volumetric shrinkage percentage (firing shrinkage percentage) before and after firing of the cell structure 1 and the firing shrinkage percentage of the material for forming outer wall 11 is not more than 0.5% is produced and fired.

Abstract: A ceramic porous body including at least Si as a chemical component, the ceramic porous body being obtained by adding a porous silica powder or a porous silica-containing compound powder to a forming raw material to prepare a clay, forming the resulting ceramic clay into a specific shape, and firing the formed product. The ceramic porous body according to the present invention does not produce carbon dioxide or toxic gas during firing and allows the firing time to be reduced in comparison with the case of using a resin powder or a carbon powder as a pore-forming agent by using the porous silica powder or the porous silica-containing compound powder as the pore-forming agent during production. Moreover, a change in pore-forming characteristics or deformation of a formed product rarely occurs.

Abstract: A method for producing a honeycomb structure 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 formed article, and the honeycomb formed article is fired to obtain a honeycomb structure, wherein the forming formulation comprises two or more types of magnesium-containing materials containing at least talc (a first magnesium-containing material), and a magnesium-containing material except talc (a second magnesium-containing material) has an average particle diameter of 4 ?m or less; and a honeycomb structure produced by the above method The above method allows the production of a well formed honeycomb structure, even when the above body contains a small of an organic material.

Abstract: There is provided a method for manufacturing a porous ceramic structure, including: firing a formed body containing ceramic particles and a combustible powder functioning as a pore former, and burning off the combustible powder to obtain the porous ceramic structure. The combustible powder has an exothermic rate of 0 to 35 ?V·min./mg, which is obtained from a differential thermal analysis. The method for manufacturing a porous ceramic structure can inhibit a crack from being generated during firing even without slowing down the temperature rise rate at the combustion range of the pore former or without lowering an oxygen content in the firing atmosphere.

Abstract: There is provided a method for manufacturing a porous ceramic structure, including: firing a formed body containing ceramic particles and a combustible powder functioning as a pore former, and burning off the combustible powder to obtain the porous ceramic structure. As the combustible powder, porous resin particles having an average particle diameter of 10 to 50 ?m and a porosity of 50 to 90% are used. The method for manufacturing a porous ceramic structure can inhibit the combustible powder functioning as a pore former from being smashed upon mixing/kneading a forming raw material and suppressing an excess heat generation upon firing and can manufacture a porous ceramic structure having a stable porosity with a good yield.

Abstract: There is disclosed a honeycomb ceramics filter, wherein an average pore diameter X (?m) and partition wall thickness W (?m) of the filter satisfy a relation of 10?W/X. According to this filter, while a predetermined trapping efficiency is maintained, a pressure loss can be prevented from increasing to be not less than a predetermined pressure loss even with use for a long period.

Abstract: A method for manufacturing a honeycomb formed body, which comprises: a mixing step of mixing two or more types of aggregate particulate materials (first mixing) to prepare a forming blend (dry powder) and then mixing the blend with water (second mixing) to prepare a forming blend (wet powder); and a kneading step of kneading the forming blend (wet powder) to prepare a clay. This method for manufacturing a honeycomb formed body allows the prevention of the generation of internal defects without the adoption of a complicated process or a troublesome operation, with ease and simplicity.

Abstract: A method for producing a honeycomb structure using, as a part of a starting material, a recycled raw material recycled from a recovered material which is produced in the production process of the honeycomb structure and originates from the starting material for the honeycomb structure, and further provides the honeycomb structure. The recycled raw material is ground so that it has an average particle diameter of 10–2000 ?m and contains 10% or less by weight of particles having an average particle diameter of 2800 ?m or more.

Abstract: A honeycomb filter includes a honeycomb-shaped filter base having a plurality of through holes and a sealing member fixed on end surfaces of the filter base in which the through holes are open. The through holes of the filter base are clogged with the sealing member in a checker flag form on each end surface so as to clog the through holes differently from the through holes sealed on the opposite end surface. The sealing member is a sheet-shaped fired body with a thickness of 3 mm or less, and a difference in coefficient of thermal expansion at temperatures of 40 to 800° C. between said sealing member and said filter base is 0.5×10?6/° C. or less. This honeycomb filter has high filtration efficiency, and very high thermal shock resistance and has high bonding strength between the sealing member and the filter base and a low pressure loss.

Abstract: There is provided a method for producing a ceramic structure, in which a concentration of at least one kind of inflammable gas (gas to be measured) in the combustion furnace is measured upon degreasing, and a condition such as temperature rise speed is adjusted according to a total concentration of the gas to be measured to control the total concentration of the gas to be measured to be a concentration of 0 to 75% of an explosion lower limit concentration of the whole gas to be measured. The method can effectively inhibit an explosion inside the furnace, can reduce the production cost, and can produce a ceramic structure with high production efficiency.

Abstract: There is provided a plugged honeycomb structure 1 including: partition walls 2 disposed so as to form a plurality of cells 3 extending from one end face 42 to the other end face 44 in the axial direction, and plugged portions 4 disposed so as to plug the cells 3 at one of the end faces, and a production method thereof. In this honeycomb structure 1, the plugged portions 4 and partition walls surrounding the plugged portions are unitarily formed. The production method includes a forming step, a plugging step for filling a plugging material, and a firing step. The plugging material contains solid particles capable of unitarily joining with at least one kind of solid particles contained in a forming raw material in a firing step. A ratio of a dimensional change (%) upon forming the partition walls out of the partition wall-forming material to a dimensional change (%) upon forming the plugged portions out of the plugging material is controlled to be within the range of 0.7% to 1.3 in the firing step.