Abstract: There are provided a honeycomb structure and a method of manufacturing the honeycomb structure, the honeycomb structure including a honeycomb structural part, which has partition walls 2 for forming a plurality of cells 3 partitioned in a honeycomb shape and for forming recesses 6 on an outer peripheral surface, and an outer wall part 5 disposed on the outer peripheral surface of the honeycomb structural part, wherein voids are formed in the recesses 6 between the outer wall part 5 and the honeycomb structural part. The honeycomb structure and the method of manufacturing the same can suppress the reduction of a temperature increasing speed while suppressing a decrease of mechanical strength and further can suppress the occurrence of cracks.

Abstract: There is provided a cell structure, where the outer wall portion has high heat-insulating ability, the cell structural portion has a high temperature rise rate, and a temperature distribution is more uniform, and a method for manufacturing the cell structure. The cell structure 1 includes: a cell structural portion 4 having partition walls forming a plurality of cells extending from one end face to the other end face, and an outer wall portion 5 disposed on an outer peripheral surface of the cell structural portion 4. The outer wall portion 5 has at least a porous layer having a porosity of 40% or more or a porous layer having a hollow body. The manufacturing method can easily manufacture the cell structure.

Abstract: A honeycomb formed article comprising a plurality of partition walls is prepared using clay mainly composed of a ceramic material, a partition wall strengthening agent obtained by mixing a partition wall strengthening material with a dispersion medium mainly composed of an amphipathic liquid compound having both hydrophilic and hydrophobic groups is coated to a plurality of partition walls existing in at least one cell opening end portion of the formed article, and thereafter the article is fired. According to this method, while largely improving enhancement of productivity and product cost reduction, a honeycomb structure superior in isostatic strength and resistance to erosion can be stably obtained.

Abstract: A marking composition comprises an inorganic pigment having an average diameter of o.1 to 5 ?m and a titanium-containing ceramic resin. The composition exhibits excellent concealing properties and heat resistance and produces a high definition marking with high contrast and excellent discrimination capability when applied to the surface of an article.

Abstract: There is provided a cell structure, where the outer wall portion has high heat-insulating ability, the cell structural portion has a high temperature rise rate, and a temperature distribution is more uniform, and a method for manufacturing the cell structure. The cell structure 1 includes: a cell structural portion 4 having partition walls forming a plurality of cells extending from one end face to the other end face, and an outer wall portion 5 disposed on an outer peripheral surface of the cell structural portion 4. The outer wall portion 5 has at least a porous layer having a porosity of 40% or more or a porous layer having a hollow body. The manufacturing method can easily manufacture the cell structure.

Abstract: The ceramic honeycomb structure according to the present invention includes a cell group having a plurality of cells which are divided each other by porous partition walls and functioning as a fluid channel, and porous outer wall surrounding and holding outermost peripheral cells located at a circumference of the cell group. In the partition walls, a part located at least one opening end of the cells of the cell group constitutes a reinforced partition wall part having higher strength than the other part of the partition walls (normal partition wall part) as well as having a variation of porosity per unit volume within ±2%. Uniform and excellent erosion resistance is achieved throughout the reinforced partition wall part.

Abstract: The ceramics honeycomb structure of the present invention is formed of a plurality of cells forming a fluid flow passage partitioned by porous partition walls, and comprising an inflow end part allowing fluid to flow therein, an outflow end part allowing fluid to flow therefrom, and an outer peripheral part including an outer peripheral surface, and is characterized by having a structure where a porosity per unit volume (cm3) gradually increases from the inflow end part side to the outflow end part side at a rate of 0.2%/mm or less, and this ceramics honeycomb structure has an excellent erosion resistance of partition walls positioned at a cell opening end part and a high compressive strength (isostatic strength) at the time of canning, and is suitable particularly as an automobile exhaust gas purification catalyst carrier.

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: There are provided a honeycomb structure and a method of manufacturing the honeycomb structure, the honeycomb structure including a honeycomb structural part, which has partition walls 2 for forming a plurality of cells 3 partitioned in a honeycomb shape and for forming recesses 6 on an outer peripheral surface, and an outer wall part 5 disposed on the outer peripheral surface of the honeycomb structural part, wherein voids are formed in the recesses 6 between the outer wall part 5 and the honeycomb structural part. The honeycomb structure and the method of manufacturing the same can suppress the reduction of a temperature increasing speed while suppressing a decrease of mechanical strength and further can suppress the occurrence of cracks.

Abstract: A coating material of the present invention is a coating material comprising: cordierite powder as a main component having a tap bulk density of 1.3 g/cm3 or more; and water. The coating material is capable of forming a coated wall (outer wall), for example, on the surface of a porous body formed of a ceramic in such a manner that defects such as generation of cracks, and peeling, and a manufacturing yield is satisfactory are not easily generated.

Abstract: A honeycomb catalyst carrier 5 of the present invention includes: a honeycomb formed cell structure 1 which is composed of a porous material having a large number of pores and has cells each functioning as a fluid passage; and an outer wall 6 composed of a porous material disposed so as to cover an outer periphery of the cell structure 1. An impregnated part 1a impregnated with a water-insoluble organic material which disappears by burning or an inorganic material is formed in an outermost peripheral part, which has a given thickness, of the porous material of the cell structure 1.

Abstract: A honeycomb formed article comprising a plurality of partition walls is prepared using clay mainly composed of a ceramic material, a partition wall strengthening agent obtained by mixing a partition wall strengthening material with a dispersion medium mainly composed of an amphipathic liquid compound having both hydrophilic and hydrophobic groups is coated to a plurality of partition walls existing in at least one cell opening end portion of the formed article, and thereafter the article is fired. According to this method, while largely improving enhancement of productivity and product cost reduction, a honeycomb structure superior in isostatic strength and resistance to erosion can be stably obtained.

Abstract: The ceramics honeycomb structure of the present invention is formed of a plurality of cells forming a fluid flow passage partitioned by porous partition walls, and comprising an inflow end part allowing fluid to flow therein, an outflow end part allowing fluid to flow therefrom, and an outer peripheral part including an outer peripheral surface, and is characterized by having a structure where a porosity per unit volume (cm3) gradually increases from the inflow end part side to the outflow end part side at a rate of 0.2%/mm or less, and this ceramics honeycomb structure has an excellent erosion resistance of partition walls positioned at a cell opening end part and a high compressive strength (isostatic strength) at the time of canning, and is suitable particularly as an automobile exhaust gas purification catalyst carrier.

Abstract: The ceramic honeycomb structure according to the present invention includes a cell group having a plurality of cells which are divided each other by porous partition walls and functioning as a fluid channel, and porous outer wall surrounding and holding outermost peripheral cells located at a circumference of the cell group. In the partition walls, a part located at least one opening end of the cells of the cell group constitutes a reinforced partition wall part having higher strength than the other part of the partition walls (normal partition wall part) as well as having a variation of porosity per unit volume within ±2%. Uniform and excellent erosion resistance is achieved throughout the reinforced partition wall part.

Abstract: A honeycomb formed body is obtained by subjecting a mixture of a raw material powder and a forming binder to extrusion, wherein the forming binder is a mixture of a wax and a thermoplastic resin and the mixing ratio of the thermoplastic resin in the forming binder is 5 to 50% by weight. A honeycomb formed body having a partition wall as thin as 25 to 100 &mgr;m can be mass-produced efficiently without generating cracks or deforming the die of extruder.

Abstract: A ceramic heater includes a body of aluminum nitride, and a heating element embedded in the body of aluminum nitride. The heating element has a resistance of (E.sup.2 /W).multidot.0.003.OMEGA. to (E.sup.2 /W).multidot.0.135.OMEGA. (E and W denote an input voltage (unit: V) and a weight (unit: g) of the body of aluminum nitride, respectively).

Abstract: The present invention includes a method for freeze molding, comprising the steps of: mixing poly(vinyl alcohol) or a modified additive thereof with a material slurry to obtain a mixture; pouring the mixture into a molding die; and subjecting the mixture in a molding die to at least one cycle of cooling and heating so as to obtain a compact. A compact obtained in this method is free from melting and can maintain its configuration even if the compact is kept at a temperature of freezing point or higher. Further, since the method does not require vacuum drying, the compact can easily be dried.