# US 2017/0282108 A1 · Porous material, method for manufacturing porous material, and honeycomb structure > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0282108 A1 - Document ID: US20170282108A1 - Status: Published application - Kind: A1 - Application number: 15/468,529 - Filed: 2017-03-24 - Published: 2017-10-05 - Earliest claimed: 2016-03-31 - Assignees: NGK Insulators, Ltd. - Applicants: Ngk Insulators, Ltd. - Inventors: Atsushi MIZUNO; Ryuta KOUNO; Shuichi ICHIKAWA - Web page: https://patentgrep.com/patent/US20170282108A1 ## CPC - B01D 46/0001: {Making filtering elements} - F01N 3/0222: {the structure being monolithic, e.g. honeycombs} - Y02T 10/12: Improving ICE efficiencies - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) - F01N: GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES (arrangements in connection with gas exhaust of propulsion units in vehicles B60K13/00; combustion-air intake silencers specially adapted for, or arranged on, internal-combustion engines F02M35/00; protecting against, or damping, noise in general G10K11/16) - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract Provided is a porous material which is not easily damaged even when being exposed to a high temperature in a low oxygen atmosphere, and has heat resistance improved. A porous material includes aggregates formed of a nonoxide containing silicon and a binding material formed of an oxide ceramic binding the aggregates to each other while keeping a plurality of pores. The porous material has a phase containing oxygen on a surface of the aggregates including a boundary surface with the binding material. In the porous material, a content ratio of oxygen in the aggregates is preferably from 2 to 25% by mass relative to the mass of the aggregates. ## Claims ### Claim 1 A porous material comprising; aggregates formed of a nonoxide containing silicon and a binding material formed of an oxide ceramic binding the aggregates to each other while keeping a plurality of pores, wherein the porous material has a phase containing oxygen on a surface of the aggregates including a boundary surface with the binding material. ### Claim 2 (depends on 1) The porous material according to claim 1, wherein a content ratio of oxygen in the aggregates is from 2 to 25% by mass relative to the mass of the aggregates. ### Claim 3 (depends on 1) The porous material according to claim 1, wherein the phase containing oxygen contains cristobalite. ### Claim 4 (depends on 2) The porous material according to claim 2, wherein the phase containing oxygen contains cristobalite. ### Claim 5 (depends on 1) The porous material according to claim 1, wherein the binding material contains crystalline cordierite in an amount of 50% by mass or more relative to the total amount of the binding material. ### Claim 6 (depends on 5) The porous material according to claim 5, wherein the binding material further contains at least one selected from a group consisting of amorphous cordierite, alumina, mullite, spinel, sapphirine, and cristobalite. ### Claim 7 (depends on 1) The porous material according to claim 1, wherein the phase containing oxygen has a film thickness of 0.2 to 3.0 μm. ### Claim 8 (depends on 2) The porous material according to claim 2, wherein the phase containing oxygen has a film thickness of 0.2 to 3.0 μm. ### Claim 9 (depends on 3) The porous material according to claim 3, wherein the phase containing oxygen has a film thickness of 0.2 to 3.0 μm. ### Claim 10 (depends on 4) The porous material according to claim 4, wherein the phase containing oxygen has a film thickness of 0.2 to 3.0 μm. ### Claim 11 (depends on 5) The porous material according to claim 5, wherein the phase containing oxygen has a film thickness of 0.2 to 3.0 μm. ### Claim 12 (depends on 6) The porous material according to claim 6, wherein the phase containing oxygen has a film thickness of 0.2 to 3.0 μm. ### Claim 13 (depends on 1) The porous material according to claim 1, wherein the aggregates are formed of silicon carbide. ### Claim 14 (depends on 1) The porous material according to claim 1, having a porosity of 35to 75%. ### Claim 15 (depends on 1) The porous material according to claim 1, having a thermal expansion coefficient of 5.5×10−6/K or less. ### Claim 16 A method for manufacturing a porous material, comprising: a forming step of obtaining a mixture by adding and mixing a raw material for a binding material containing a cordierite forming raw material and an organic binder to powdery aggregates formed of a nonoxide containing silicon, and then forming the mixture to obtain a formed body; a firing step of calcinating the obtained formed body in an atmosphere containing oxygen to remove the organic binder in the formed body, and then firing the formed body in a temperature range of 1370 to 1450° C. to obtain a porous fired body in which the powdery aggregates are bound to each other with an oxide ceramic; and a porous material forming step of subjecting the obtained fired body to a heat treatment in a temperature range of 1000 to 1400° C. in an atmosphere containing oxygen, and thereby forming a phase containing oxygen on a surface of the powdery aggregates including a boundary surface with the oxide ceramic to obtain a porous material. ### Claim 17 (depends on 16) The method for manufacturing a porous material according to claim 16, wherein the phase containing oxygen contains an alkali metal in an amount of 0.05% by mass or more relative to the porous material. ### Claim 18 (depends on 1) A honeycomb structure formed by the porous material according to claim 1, having a shape including a partition wall defining a plurality of cells extending from a first end face as one end face to a second end face as the other end face. ### Claim 19 (depends on 18) The honeycomb structure according to claim 18, comprising a plugging portion disposed in each of an open end of a predetermined cell on the first end face and an open end of a residual cell on the second end face.