Cordierite-Indialite-Plain Titanium Stone Structure Ceramic Body, Batch Composition Mixture, and Method for Producing Ceramic Body from the Same

Abstract

To provide a ceramic body having a high porosity, a relatively large median pore diameter, a narrow pore size distribution, and a relatively low CTE, and a method for producing the ceramic body.SOLUTION: In a ceramic body, %P≥50% (where %P is an average bulk volume porosity) and df≤0.36 (where df is (d50-d10) / d50). The ceramic body contains a crystalline phase containing a total weight percentage of at least 85 wt.% of cordierite and indialite, and contains a crystalline phase containing up to 10 wt.% of a pseudobrookite structure. The ceramic body comprises, when expressed as a weight percentage based on oxides: 1 wt.% to 11 wt.% of titania, and 89 wt.% to 99 wt.% of MgO, Al2O3, and SiO2.SELECTED DRAWING: Figure 3

Description

Priority

[0001] This application claims priority under Section 119 of the United States Patent Act to U.S. Provisional Patent Application No. 62 / 725,591, filed on 31 August 2018, the contents of which the entire contents of the said Provisional Patent Application are incorporated herein by reference. This application is a divisional application of Japanese Patent Application No. 2021-511643, filed on 29 August 2019. [Technical Field]

[0002] Exemplary embodiments of the present disclosure relate to cordierite and imitation titanium granite structured ceramic bodies, and more particularly to porous cordierite and imitation titanium granite structured honeycomb bodies useful for engine exhaust gas aftertreatment and other filtration applications. [Background technology]

[0003] Cordierite-based honeycomb and aluminum titanate-based honeycomb have been widely used in a variety of exhaust gas mitigation / treatment applications, for example, in catalytic converters and in particulate filters for controlling emissions from diesel and gasoline engines.

[0004] Diesel particulate filters (DPFs) and gasoline particulate filters (GPFs) can be manufactured by forming a sealed honeycomb body from a porous ceramic honeycomb body by sealing some of the channels in a certain pattern.

[0005] Exhaust gas flows through the porous walls of a sealed ceramic honeycomb body. Along the flow path through the porous walls, particulate matter derived from the exhaust gas can be deposited in the pores, on the surface of the porous walls, or on a soot layer formed on or deposited on the surface of the porous walls, thereby providing filtration of particulate matter from the exhaust gas. The formed soot layer can be periodically burned during the regeneration cycle, thereby allowing the DPF / GPF to have a design life comparable to the life of the vehicle. [Overview of the Initiative]

[0006] Exemplary embodiments of the present disclosure provide a ceramic body having a cordierite-indialite-plytitanite crystalline structure.

[0007] Exemplary embodiments of the present disclosure also provide a ceramic honeycomb body having porous walls comprising a cordierite-indialite-plytitanite crystalline structure.

[0008] Exemplary embodiments of the present disclosure also provide batch composition mixtures useful for producing cordierite-indialite-plicatinite crystalline structures.

[0009] One or more exemplary embodiments of the present disclosure also provide a method for producing a ceramic body having a cordierite-indialite-plytitanite crystalline structure.

[0010] Further features of this disclosure are described below, some of which will become apparent from this description or can be learned by practicing the embodiments disclosed herein.

[0011] In one embodiment of the present disclosure, the embodiments of the present disclosure are: %P ≥ 50% (where %P is the mean bulk volume porosity); df ≤ 0.36 (where df is (d 50 -d 10 ) / d 50 The ceramic body is provided, comprising a crystalline phase containing cordierite and indialite in a total weight percentage of at least 85% by weight, and a crystalline phase containing a quasi-plated titaniumite structure in a total weight percentage of up to 10% by weight, wherein the ceramic body is expressed in weight percentage on an oxide basis: 1% to 11% by weight of titania, and 89% to 99% by weight of MgO, Al2O3, and SiO2 (where the relative weight ratios of MgO:Al2O3:SiO2 are within the fields defined by 15.6:34.0:50.4, 12.6:34.0:53.4, 13.9:30.7:55.4, and 16.9:30.7:52.4); or 2.5% to 11% titania, and 89% to 97.5% by weight of MgO, Al2O3, and SiO2 (where the relative weight ratios of MgO:Al2O3:SiO2 are within the fields defined by 15.6:34.0:50.4, 12.6:34.0:53.4, 12.0:35.7:52.3, and 15.0:35.7:49.3). It contains.

[0012] Another exemplary embodiment discloses a ceramic body comprising a crystalline phase containing cordierite and indialite in a total weight percentage of 85% to 92% and a second crystalline phase of a pseudo-titaniumite structure containing armacolite in a total weight percentage of up to 10%. The above ceramic body contains, when expressed as an oxide-based weight percentage, 1% to 11% by weight of titania, and 89% to 99% by weight of MgO, Al2O3, and SiO2 (where the relative weight ratios of MgO:Al2O3:SiO2 are within the fields defined by 15.6:34.0:50.4, 12.6:34.0:53.4, 13.9:30.7:55.4, and 16.9:30.7:52.4); 55% ≤ %P ≤ 72%; 8μm≦d 50 ≤20μm (where d 50 (where is the pore median diameter); 0.16 ≤ df ≤ 0.32 (where df is (d 50 -d 10 ) / d 50 It is.

[0013] Another exemplary embodiment discloses a ceramic body comprising a crystalline phase containing cordierite and indialite in a total weight percentage of 85% to 92% and a second crystalline phase of a pseudo-titaniumite structure containing armacolite in a total weight percentage of up to 10%. When expressed as weight percentages based on oxides, the ceramic body contains 2.5% to 11% of titania, and 89 wt% to 97.5 wt% of MgO, Al2O3, and SiO2 (where the relative weight ratio of MgO:Al2O3:SiO2 is within the fields defined by 15.6:34.0:50.4, 12.6:34.0:53.4, 12.0:35.7:52.3, and 15.0:35.7:49.3); 55% ≤ %P ≤ 72%; 8 μm ≤ d 50 ≤ 20 μm (where d 50 is the pore median diameter); 0.16 ≤ df ≤ 0.32 (where df is (d 50 - d 10 ) / d 50 ).

[0014] In another exemplary embodiment, a batch composition mixture is disclosed. The batch composition mixture, when expressed as weight percentages based on oxides: 1 wt% to 11 wt% of titania, and 89 wt% to 99 wt% of MgO, Al2O3, and SiO2 (where the relative weight ratio of MgO:Al2O3:SiO2 is within the fields defined by 15.6:34.0:50.4, 12.6:34.0:53.4, 13.9:30.7:55.4, and 16.9:30.7:52.4); or 2.5% to 11% of titania, and 89 wt% to 97.5 wt% of MgO, Al2O3, and SiO2 (where the relative weight ratio of MgO:Al2O3:SiO2 is within the fields defined by 15.6:34.0:50.4, 12.6:34.0:53.4, 12.0:35.7:52.3, and 15.0:35.7:49.3) comprises a magnesia source, an alumina source, a silica source, and a titania source.

[0015] Yet another exemplary embodiment discloses a method for manufacturing a ceramic body. The method: 20 wt% to 42 wt% of a magnesia source, 25 wt% to 40 wt% of an alumina source, A silica source of 15% to 30% by weight, and Titania source of 1% to 10% by weight, A step of providing an inorganic component comprising the above-mentioned magnesia source, alumina source, silica source, and titania source, wherein the above-mentioned weight percentages of each are based on 100% of the total weight of the inorganic material present; The step of mixing the above inorganic components with an organic binder, a pore-forming agent in an amount of 26% SA to 56% SA by weight, and a liquid vehicle to form a batch composition mixture, wherein the % SA by weight is a weight percentage of the added amount based on 100% of the total weight of the inorganic components; The step of molding the above batch composition mixture to form a base material; and A step of firing the above-mentioned substrate under conditions effective for converting it into a ceramic body comprising a crystalline phase containing cordierite and indialite in a total weight percentage of at least 85% by weight, and a crystalline phase containing a quasi-titaniumite structure in a total weight percentage of up to 10% by weight. Includes.

[0016] Please understand that both the above "Summary of the Invention" and the following "Modes for Carrying Out the Invention" are intended to provide numerous examples and further enhance the understanding of this disclosure.

[0017] The accompanying drawings are included to provide a further understanding of this disclosure, are incorporated herein and constitute part of this specification, illustrate exemplary embodiments, and serve to illustrate the principles of this disclosure in conjunction with this description. These drawings are not necessarily to exact scale. The same reference numbers are used to refer to identical or substantially similar parts. [Brief explanation of the drawing]

[0018] [Figure 1A] A perspective view of a ceramic body embodied as a honeycomb structure containing cordierite, indialite, and quasi-titaniumite crystalline structure ceramic according to an embodiment of the present disclosure. [Figure 1B]Enlarged end view of a portion of the ceramic honeycomb body shown in Figure 1A according to an embodiment of the present disclosure. [Figure 1C] A perspective view of a ceramic body embodied as a sealing honeycomb body containing cordierite, indialite, and quasi-plated titaniumite crystalline structure ceramic according to an embodiment of the present disclosure. [Figure 2] A partial cross-sectional view of an extrusion machine showing a honeycomb substrate being extruded according to an embodiment of the present disclosure. [Figure 3] A triangular graph of the relative weight ratio of MgO:Al2O3:SiO2 in a field (based on a total of 100% MgO, Al2O3, and SiO2) according to embodiments of the present disclosure. [Figure 4A] Representative micrographs of polished cross-sections of the porous walls of exemplary ceramic bodies (e.g., Example E9) including cordierite, indialite, and quasi-titaniumite crystalline structure ceramics according to embodiments of the present disclosure. [Figure 4B] Representative micrographs of polished cross-sections of the porous walls of exemplary ceramic bodies (e.g., E7C) including cordierite, indialite, and quasi-titaniumite crystalline structure ceramics according to embodiments of the present disclosure. [Figure 4C] Representative micrographs of polished cross-sections of the porous walls of exemplary ceramic bodies (e.g., Example E20) including cordierite, indialite, and quasi-titaniumite crystalline structure ceramics according to embodiments of the present disclosure. [Figure 5] A method for producing a ceramic body including cordierite, indialite, and quasi-titaniumite crystalline structure ceramic according to embodiments of the present disclosure. [Modes for carrying out the invention]

[0019] The present disclosure will now be described in more detail with reference to the accompanying drawings illustrating exemplary embodiments. However, the present invention can be embodied in a number of different forms and should not be construed as being limited to the embodiments described herein. In the drawings, the sizes and relative sizes of feature parts and components may be exaggerated for illustrative purposes and therefore may not be shown to exact scale. Similar reference numerals in the drawings may refer to similar elements.

[0020] When an element is said to be "on," "connected to," or "coupled to" another element, it should be understood that the element may be directly on or directly connected to the other element, or there may be intervening or interconnecting elements. In contrast, when an element is said to be "directly on" or "directly connected to" another element, there are no intervening elements.

[0021] Various NOx removal catalysts, diesel oxidation catalysts (DOCs), three-way catalysts (TWCs), or selective catalyst reduction (SCR) catalysts can be incorporated into a sealed honeycomb filter body. Relatively high catalytic efficiency can be achieved by utilizing a high catalyst load. A washcoat load of 100 g / l is currently common, and in the future, loads may exceed 150 g / l. In various embodiments, high catalyst loads at low back pressure can be provided by a honeycomb filter body made from a ceramic honeycomb structure with extremely high porosity and relatively large pore diameters.

[0022] Porous cordierite and aluminum titanate-feldspar composite honeycomb ceramic articles can exhibit low thermal expansion coefficient, relatively high porosity, low Young's modulus, and high strength for high-performance automotive catalytic converters and diesel particulate filters. For example, as disclosed in U.S. Patent No. 8,394,167 (the contents of which are incorporated in whole by reference), a cordierite-mullite-aluminum titanate (CMAT) composite is provided, which exhibits improved strength compared to aluminum titanate-feldspar composites and better volumetric heat capacity compared to cordierite, due to the assembly and microstructure of the phases of the CMAT ceramic material. The combination of these two advantages makes CMAT materials particularly suitable for applications requiring high porosity, such as TWC and SCR applications, including ceramic honeycomb filter bodies. The platylithite structural phase in these CMAT composites can be stabilized by magnesium in the solid solution, thereby making them more thermodynamically stable than the aluminum titanate phase found in aluminum titanate feldspar (AT) composites, and better resistant to high-temperature thermal decomposition and accelerated decomposition when exposed to glass-forming elements such as copper, manganese, cobalt, bismuth, and their compounds. However, the various embodiments described herein offer various combinations of high porosity, relatively large pore median diameter, narrow pore size distribution, and relatively low CTE.

[0023] Exemplary embodiments of ceramic bodies disclose cordierite, indialite, and quaternite structures in a composition range that provide unexpectedly superior performance over prior art AT, cordierite, and cordierite-mullite-aluminum titanate (CMAT) materials. More specifically, this disclosure provides: relatively high average bulk volume porosity (e.g., %P≧50%); relatively narrow pore size distribution (e.g., df≦0.36(where df is (d 50 -d 10 ) / d 50The present invention discloses a ceramic body having a relatively high total weight percentage (e.g., at least 85% by weight) of a crystalline phase including cordierite and indialite; and up to 10% by weight of a crystalline platylithite structure phase (e.g., armalcolite).

[0024] In particular, the above ceramic materials, when expressed in weight percentage based on oxide: 1% to 11% by weight of titania, and 89% to 99% by weight of MgO, Al2O3, and SiO2 (where the relative weight ratios of MgO:Al2O3:SiO2 are within the fields defined by 15.6:34.0:50.4, 12.6:34.0:53.4, 13.9:30.7:55.4, and 16.9:30.7:52.4); or 2.5% to 11% titania, and 89% to 97.5% by weight of MgO, Al2O3, and SiO2 (where the relative weight ratios of MgO:Al2O3:SiO2 are within the fields defined by 15.6:34.0:50.4, 12.6:34.0:53.4, 12.0:35.7:52.3, and 15.0:35.7:49.3). It contains.

[0025] definition Cordierite-(Mg,Fe)2Al3(Si5AlO 18 )~(Fe,Mg)2Al3(Si5AlO 18 A magnesium aluminum cyclosilicate having the following formula: ). Iron and nickel may be present in small amounts, i.e., less than 4% by weight. Using cordierite crystals, extremely low thermal expansion can be obtained along one axis.

[0026] Indialyte-cordierite is a hexagonal type 2 high-temperature polymorphic aluminosilicate phase, which has the same structure as beryl, (Si,Al)6O 18It has a random distribution of Al in the ring. It is compositionally similar to cordierite and also exhibits negative thermal expansion along one crystal axis. The conversion from indialite to cordierite occurs slowly, and indialite is metastable below approximately 1250°C. Small amounts of iron and nickel may be present, i.e., less than 4% by weight.

[0027] A hard crystalline phase material that arises as spinel-octahedral crystals and consists of magnesium oxide and aluminum oxide.

[0028] MgSiO3 is an orthorhombic material from the pyroxene group consisting of enstatite-magnesium silicate.

[0029] Rutile - A ceramic material mainly composed of titanium dioxide (TiO2).

[0030] Titanite structural phases - thialite (Al2TiO5), titanite (Fe2TiO5), armacolite (Mg,Fe 2+ A structural phase which is a solid solution of one or more of Ti2O5 and caluite (MgTi2O5).

[0031] Crystalbolite-silica high-temperature polymorph. This means that it has a distinct crystal structure despite having the same chemical formula as quartz (SiO2).

[0032] Amorphous phase – Glass containing mainly silica, with less than a small amount of alumina, magnesia, titania, and oxide impurities of sodium, calcium, iron, and nickel.

[0033] Further embodiments of this disclosure will now be described with reference to the tables and Figures 1A-5 disclosed and described herein. In some embodiments, the ceramic body 100 can be embodied as a honeycomb body as shown in Figures 1A and 1B. The ceramic body 100 embodied as a honeycomb body may comprise a matrix of interconnected porous walls 102, which form a honeycomb of a plurality of channels 104 extending along the axial length of the ceramic body 100 from a first end 103 (e.g., an inlet end) to a second end 105 (e.g., an outlet end). The channels 104 may be parallel to one another. The shape of the channels in cross-section, whose contour is formed by the walls 102, may be square as shown in Figures 1A and 1B. However, the cross-sectional channel shape may be rectangular (but not square), triangular, octagonal, hexagonal, rhombus, circular, other polygonal, or a combination thereof, and may have rounded corners, chamfered corners, square corners, or a combination thereof.

[0034] When the ceramic body 100 is configured as a honeycomb, it can have a configuration in which the lateral wall thickness tw of the walls 102 is 0.002 inches to 0.016 inches (0.05 mm to 0.41 mm, see Figure 1B), and in some embodiments, 0.004 to 0.012 inches (0.10 mm to 0.30 mm). Furthermore, the connected porous walls 102 may have a substantially constant thickness traversing the honeycomb, or may have various thicknesses. For example, the wall thickness tw of the connected porous walls 102 can be increased near the surface 106 of the ceramic body 100, thereby providing a relatively thick, ring-shaped wall near the surface 106.

[0035] If the ceramic body 100 is configured as the honeycomb body shown in Figure 1A or the eye-sealing honeycomb body shown in Figure 1C, for example, 15.5 cells / cm 2 ~77.5 cells / cm 2It can have an average cell density of (100 cpsi to 500 cpsi). Other cell densities are also available. An exemplary geometry of the ceramic body 100 is defined herein as a 400 / 8 honeycomb body, with a density of 400 cpsi (62 cells / cm³). 2 ) average cell density and lateral wall thickness of approximately 8 mil (0.20 mm), or as defined herein as a 400 / 6 honeycomb, 400 cpsi (62 cells / cm²). 2 The ceramic body 100 may have an average cell density and a wall thickness of approximately 6 mils (0.15 mm). Other geometries of the ceramic body 100 include, for example, average cell density / lateral wall thickness combinations of 100 / 17, 200 / 12, 200 / 19, 270 / 19, 300 / 8, 200 / 8, and 350 / 12. Other suitable combinations of cell density and lateral wall thickness can also be used.

[0036] In some honeycomb structures, when the ceramic body 100 is embodied as a sealed ceramic honeycomb 100P, certain ones of the channels 104 can be sealed. For example, as shown in Figure 1C, a sealed ceramic honeycomb 100P is shown that can be included in particulate filters for diesel or gasoline engine applications. In the embodiment shown in Figure 1C, some of the channels 104L may have a larger hydraulic area than other relatively smaller channels 104S, as disclosed, for example, in U.S. Patent Nos. 6,843,822; 6,696,132; 7,247,184; and 7,601,194. In other embodiments, as disclosed, for example, in U.S. Patent Nos. 4,329,162; 6,849,181; 8512,433; and 8236,083, the sealed ceramic honeycomb 100P may include inlet and outlet channels of the same size. Other filter-eye sealing patterns are also possible, such as those disclosed in U.S. Patent No. 9,757,675; U.S. Patent No. 8,673,064; U.S. Patent No. 4,417,908; and U.S. Patent No. 8,844,752.

[0037] The outermost cross-sectional shape of the ceramic body 100 (and the sealed honeycomb body 100P) may be any desired outer cross-sectional shape, such as a circle, oval, ellipse, triangle or trefoil, track-shaped, square, or rectangular cross-section (as shown in Figures 1A and 1C). However, the honeycomb body 100 and the sealed honeycomb body are not limited to these cross-sectional shapes. Other cross-sectional shapes may be used. The ceramic body 100 used herein includes, but is not limited to, the honeycomb body and the sealed honeycomb body 100P.

[0038] Exemplary embodiments of the ceramic body 100 of this disclosure can have a relatively high level of total bulk porosity, which is open and connected porosity. For example, the ceramic body 100 of the composition described herein can have an average bulk porosity %P, where, as determined by mercury penetration porosimetry, %P≧50%, %P≧55%, %P≧60%, and even %P≧65%. In some embodiments, the average bulk porosity %P can be 50%≦%P≦72%, 55%≦%P≦72%, 60%≦%P≦72%, and even 65%≦%P≦72%. Such a range of porosity for the ceramic body 100 of this disclosure can provide low back pressure while providing sufficient overall strength and thermal shock resistance when used as a sealed honeycomb body 100P for particulate filters.

[0039] In addition to a relatively high total porosity, the ceramic body 100 of this disclosure may also have a relatively narrow pore size distribution. This narrow pore size distribution can be demonstrated by the fact that the percentage of relatively fine pores or relatively large pores is minimal, or, in some embodiments, the percentage of both relatively fine and relatively large pores is minimal. Such a narrow pore size distribution has the advantage of providing low back pressure, even when coated with a catalyst-containing washcoat. Furthermore, a narrow pore size distribution may be beneficial when the ceramic body 100 is used in diesel and / or gas engine exhaust gas filtration applications, as it may provide a small soot load pressure drop and excellent soot capture efficiency.

[0040] For this purpose, the relative pore size distribution is determined by mercury penetration porosimetry using Washburn's equation. For example, quantity d 50 This represents the pore median diameter (MPS) based on the pore volume (measured in micrometers). Therefore, d 50 This is the pore diameter through which mercury penetrates 50% of the open porosity of the ceramic body 100. 90 90% of the pore volume is d 90 The pore diameter is composed of pores with a diameter smaller than the value of , and therefore d 90This is also equal to the pore diameter through which mercury penetrates 10 volume percent of the open porosity of the ceramic. Furthermore, the amount d 10 10% of the pore volume is d 10 The pore diameter is composed of pores with a diameter smaller than the value of , and therefore d 10 This is equal to the pore diameter through which mercury penetrates 90% by volume of the open porosity of the ceramic. 10 and d 90 The value is also expressed in micrometers.

[0041] d 50 According to one aspect of this disclosure, the porous wall 102 of the ceramic body 100 after firing is d 50 ≥10.0μm, d 50 ≥12.0μm, d 50 ≥13.0μm, d 50 ≥15.0 μm, and in some embodiments d 50 Pore ​​median diameter (d) ≥ 18.0 μm 50 ) can have. Furthermore, the porous wall 102 of the ceramic body 100 after firing has 7 μm ≤ d50 ≤ 20 μm, 10 μm ≤ d 50 ≤20μm, 12μm ≤d 50 ≤20μm, and in some embodiments, 15μm ≤d 50 Pore ​​median diameter (d) in the range of ≤20 μm 50 ) can have.

[0042] df The pore size distribution of the open-connected porosity of ceramic body 100, the relatively small pore fraction (d 50 The narrowness of the following can be characterized by the coefficient d (df), where df = {(d 50 -d 10 ) / d 50In exemplary embodiments of the ceramic body 100, df may be df ≤ 0.36, df ≤ 0.32; df ≤ 0.30, df ≤ 0.25, and even df ≤ 0.22. Embodiments of the extremely narrow pore size distribution described herein may exhibit d coefficients of d ≤ 0.20, df ≤ 0.18, and even df ≤ 0.17. In some embodiments, the porous wall 102 of the fired ceramic body 100 may have df of 0.16 ≤ df ≤ 0.32, 0.16 ≤ df ≤ 0.30, 0.16 ≤ df ≤ 0.25, 0.16 ≤ df ≤ 0.22, and even 0.16 ≤ df ≤ 0.20.

[0043] dB Pore ​​fraction with relatively large pore size distribution (d 10 from d 90 The relative measure of narrowness, including up to , can be characterized by the d width (dB) of the pore size distribution of the open-connected porosity of the ceramic body 100. For example, the d width (dB) of the pore size distribution of the open-connected porosity of the ceramic body 100 may be dB≦1.1, dB≦0.85, dB≦0.80, dB≦0.70, and even dB≦0.60 in some embodiments, where dB={(d 90 -d 10 ) / d 50 In some embodiments, the porous wall 102 of the fired ceramic body 100 can have dB values ​​of 0.45≦dB≦1.1, 0.45≦dB≦0.85, 0.45≦dB≦0.70, 0.45≦dB≦0.60, and even 0.45≦dB≦0.55.

[0044] CTE The coefficient of thermal expansion (CTE) of the ceramic body 100, which includes ceramics, was found to be extremely low. According to exemplary embodiments, the ceramic material of the present invention exhibits a low coefficient of thermal expansion, which was found to result in excellent thermal shock resistance (TSR). As will be understood by those skilled in the art, TSR is inversely proportional to the coefficient of thermal expansion (CTE). That is, the ceramic body 100 with a low coefficient of thermal expansion can also have relatively high thermal shock resistance and, therefore, can withstand the wide temperature fluctuations that occur in engine exhaust gas filtration applications.

[0045] Accordingly, in exemplary embodiments, the ceramic body 100 of the Disclosure, including the ceramic phase described herein, can exhibit a relatively low coefficient of thermal expansion (CTE) in at least one direction when measured by dilammetry. In particular, CTE ≤ 14 × 10 -7 / ℃, CTE ≤ 12 × 10 -7 / ℃, CTE ≤ 10 × 10 -7 / ℃, and furthermore, CTE ≤ 9 × 10 -7 A temperature of / ℃ can be achieved, and these are all measured over a temperature range of 25℃ to 800℃. In some embodiments, the CTE over the temperature range of 25℃ to 800℃ is 7 × 10⁻⁶. -7 / ℃≦CTE≦14×10 -7 / ℃; 7×10 -7 / ℃≦CTE≦12×10 -7 / ℃; Furthermore, 7 × 10 -7 / ℃≦CTE≦10×10 -7 It can be / ℃. In a further embodiment, the CTE over the temperature range of 25℃ to 800℃ is 3 × 10 -7 / ℃≦CTE≦14×10 -7 / ℃, 3×10 -7 / ℃≦CTE≦12×10 -7 / ℃, and furthermore, 3 × 10 -7 / ℃≦CTE≦10×10 -7 It can be set to / ℃. The ceramic body 100 has a microcrack index Nb of 0.10 or higher. 3It can be characterized as a microcrack body having the microcrack index Nb. In some embodiments, the microcrack index Nb 3 is 0.10 ≤ Nb 3 It is acceptable for the value to be ≤0.43.

[0046] combination The above average bulk porosity (%P) and pore median diameter (d 50 The ceramic body 100, exhibiting a combination of low df and / or low dB and low CTE (RT ~ 800°C), can provide a small clean and soot pressure drop while maintaining useful filtration efficiency and improved thermal shock resistance when the ceramic body 100 of this disclosure is used in diesel or gasoline exhaust gas filtration applications.

[0047] Particularly effective examples of the ceramic body 100 may include the ceramic compositions described herein, further comprising the average bulk porosity (%P) of the linked porous wall 102, where P% ≥ 50%, d 50 The pore median diameter (d) of ceramic body 100 is ≥7.0 μm. 50 )(here d 50 (where d is the pore median diameter), df ≤ 0.36 (where df = {(d 50 -d 10 ) / d 50}, and when measured at room temperature from 25°C to 800°C, CTE ≤ 14 × 10 -7 It can have a temperature of / ℃. In some embodiments, the ceramic body 100 may include the ceramic composition described herein, and furthermore, the average bulk porosity (%P) of the connected porous wall 102 is 50% ≤ P% ≤ 72%, and 7.0 μm ≤ d 50 Pore ​​median diameter (d) ≤ 20.0 μm 50 ), 0.16≦df≦0.36, and 3×10 -7 / K≦CTE≦14×10 -7 It can have a temperature of / ℃.

[0048] Other specific exemplary embodiments of this disclosure may include the ceramic compositions described herein, and further: 55% ≤ %P ≤ 72%; 8 μm ≤ d 50≤20 μm; 0.16 ≤ df ≤ 0.32; and when measured at 25 °C to 800 °C, 3×10 -7 / °C ≤ CTE ≤ 14×10 -7 / °C can be achieved. Further, certain other exemplary embodiments are: 60% ≤ %P ≤ 72%; 10 μm ≤ d 50 ≤20 μm; 0.16 ≤ df ≤ 0.25; and when measured at 25 °C to 800 °C, 3×10 -7 / °C ≤ CTE ≤ 13×10 -7 / °C can be achieved.

[0049] Notably, some exemplary embodiments are: 60% ≤ %P ≤ 72%; 12 μm ≤ d 50 ≤20 μm; 0.16 ≤ df ≤ 0.20; and when measured at 25 °C to 800 °C, 3×10[[ID= 17]] -7 / °C ≤ CTE ≤ 12×10 -7 / °C can be achieved. Further exemplary embodiments are: 60% ≤ %P ≤ 72%; 13 μm ≤ d 50 ≤20 μm; 0.16 ≤ df ≤ 0.18; and when measured at 25 °C to 800 °C, 3×10 -7 / °C ≤ CTE ≤ 12×10 -7 / °C can be achieved. Such properties are extremely useful for use in particulate filter applications.

[0050] As already outlined, the exemplary embodiments of the present disclosure provide a ceramic body 100 that includes a ceramic composite containing a primary crystalline phase consisting of a combination of cordierite and indialite, and a secondary crystalline phase containing a solid solution with a pseudobrookite structure phase. In particular, the ceramic body 100 includes a composite crystalline phase containing at least 85 wt% of cordierite and indialite, and a secondary crystalline phase containing up to 10 wt% of a solid solution pseudobrookite structure phase. Other phases may be present.

[0051] The crystalline phases of cordierite and indialite, when added together, can be 85% to 92% by weight based on 100% by weight of the present inorganic matter. For example, in one or more embodiments, the crystalline phase of cordierite can be 53% to 78% by weight based on 100% by weight of the present inorganic matter. The crystalline phase of indialite can be 15% to 35% by weight based on 100% by weight of the present inorganic matter. In some embodiments, the lamellarite structural phase in the ceramic body 100 can be 2% to 8% by weight based on 100% by weight of the present inorganic matter. The lamellarite structural phase may include the crystalline phase of armalcolite.

[0052] Furthermore, the ceramic body 100 may contain an additional crystalline phase of mullite, which can be 1.5% to 3% by weight based on 100% by weight of the present inorganic matter. The ceramic body 100 should contain substantially no crystalline phase of rutile. For example, the crystalline phase of rutile may be less than 1.0% by weight based on 100% by weight of the inorganic matter present in the ceramic body 100. In some embodiments, a crystalline phase of enstatite or cristobalite may be included in an amount less than 2.0% by weight based on 100% by weight of the present inorganic matter, etc. In some embodiments, the ceramic body 100 may contain less than 7% by weight of amorphous phase based on 100% by weight of the present inorganic matter.

[0053] The weight percentages and identification of the various phases present herein are achieved by the Rietveld method and are expressed as percentages of 100% by weight of the total weight of inorganic matter present in the ceramic body 100.

[0054] Furthermore, when the ceramic body 100 is expressed in weight percentage based on oxide: 1% to 11% by weight of titania, and a total of 90% to 99% by weight of MgO (magnesium oxide), Al2O3 (alumina), and SiO2 (silica), as best illustrated in region 340 of Figure 3 (where the relative weight ratios of MgO:Al2O3:SiO2 are within the fields defined by 15.6:34.0:50.4, 12.6:34.0:53.4, 13.9:30.7:55.4, and 16.9:30.7:52.4); or 2.5% to 11% by weight of titania, and a total of 89% to 97.5% by weight of MgO (magnesium oxide), Al2O3 (alumina), and SiO2 (silica), as best illustrated in region 342 of Figure 3 (where the relative weight ratios of MgO:Al2O3:SiO2 are within the fields defined by 15.6:34.0:50.4, 12.6:34.0:53.4, 12.0:35.7:52.3, and 15.0:35.7:49.3). This may include the following. As illustrated and described, the relative weight ratio of these (MgO:Al2O3:SiO2) totals 100%.

[0055] In other embodiments, the ceramic body 100 comprises 2% to 6% by weight of titania, and 94% to 98% by weight of MgO, Al2O3, and SiO2 (where the relative weight ratio of MgO:Al2O3:SiO2 is within the fields defined by 14.3:34.9:50.8; 13.3:34.9:51.8; 14.3:32.3:53.4; and 15.3:32.3:52.4).

[0056] Therefore, with respect to oxide concentration, in embodiments having an MgO:Al2O3:SiO2 oxide ratio within the edge boundary of region 340, the ceramic body 100 can contain 1% to 11% by weight of titania, and in embodiments having an MgO:Al2O3:SiO2 oxide ratio within the edge boundary of region 342, it can contain 2.5% to 11% of titania.

[0057] In some embodiments, the ceramic body 100 may further have a titania (TiO2) oxide concentration of 1% to 6% by weight, based on 100% by weight of total inorganic oxides present in the ceramic body 100. In other embodiments, the ceramic body 100 may further have a titania (TiO2) oxide concentration of 2% to 6% by weight. Furthermore, in terms of weight percentage of oxides, in some embodiments, the ceramic body 100 may have a magnesia (MgO) oxide concentration of 12% to 17% by weight, or 12.5% ​​to 14% by weight, based on 100% by weight of total inorganic oxides present in the ceramic body 100.

[0058] It should be noted that the presence of titania, along with the cordierite and indialite phases, provides not only relatively high porosity (%P) and a narrow pore size distribution, but also a low CTE. Although not constrained by theory, the function of titania is thought to be to generate a stable liquid during reactive sintering that moves in response to capillary forces and fills undesirable fine pores. This makes it possible to narrow the pore size distribution nominally compared to stoichiometric cordierite. Therefore, a particulate filter utilizing the ceramic body 100 embodied as a sealed honeycomb body 100P can have excellent permeability, washcoat compatibility, and filtration efficiency.

[0059] In exemplary embodiments of the ceramic body 100 of this disclosure, E may have an E of 4.5 GPa or less, where E is the Young's modulus of the ceramic body 100 at room temperature (RT) in units of GPa. In other exemplary embodiments, the ceramic body 100 may have an E of 2.0 GPa or less, and even more specifically, 1.5 GPa or less. In some embodiments, E may be between 1.33 GPa and 4.5 GPa, further between 1.33 GPa and 1.5 GPa, and even further between 1.33 GPa and 2.0 GPa.

[0060] According to exemplary embodiments of this disclosure, the ceramic body 100 exhibits a preferred crystallographic texture of the cordierite phase, which can be quantified by the i-ratio calculated from the (110) and (200) surface X-ray diffraction (XRD) peak intensities. With respect to the axial i-ratio, the XRD peak intensities were measured perpendicular to the wall 102 of the ceramic body 100. With respect to the transverse i-ratio, the XRD peak intensities were measured on the wall surface or on a slightly polished honeycomb wall surface. The peak intensities of cordierite can be extracted from the contribution of overlapping peaks of other phases present using Rietveld deconvolution. In exemplary embodiments of this disclosure, the cordierite phase of the ceramic body exhibits an axial i-ratio of 0.43 to 0.59 and a transverse i-ratio of 0.80 to 0.88. In some embodiments, the axial i-ratio may be less than 0.55, and even less than 0.5.

[0061] Extrusion molding method Exemplary embodiments of this disclosure also provide a method for producing cordierite-indialite-titanium platylite composite ceramics from inorganic powder raw materials, organic powder materials, a liquid vehicle (e.g., water), and processing aids. The above method is based on selected particle sizes (e.g., d) outlined herein. 50 The process includes the step of providing an inorganic batch composition mixture containing sources of magnesia, alumina, silica, and titania, which may have a concentration (dB) and a weight percentage (wt%). Next, the inorganic batch composition mixture can be mixed and / or kneaded with one or more processing aids selected from the group consisting of: organic binders, pore-forming agents, and other organic powder materials; liquid vehicles; and plasticizers and lubricants to form a plasticized batch composition mixture 210. The plasticized ceramic precursor batch composition mixture 210 can be molded or otherwise formed to form a base material 100G (see Figure 2), such as a honeycomb base material. Subsequently, the base material 100G can be dried and then fired under conditions effective for converting it into a ceramic body 100 having the above-described cordierite-indialite-plytitanite composite crystalline composition.

[0062] For example, the plasticized batch composition can be molded into a substrate 100G by an extrusion molding method. For example, Figure 2 shows a lateral cross-sectional view of an exemplary embodiment of an extrusion molding machine 200 (e.g., a continuous twin-screw extrusion molding machine). The extrusion molding machine 200 includes a barrel 212, which includes a chamber 214 formed therein. The barrel 212 may be monolithic or may be formed from a plurality of barrel segments connected in a continuous longitudinal direction 215 (e.g., in the direction indicated by the arrow). The chamber 214 extends through the barrel 212 in the longitudinal direction 215 between the upstream side 215U and the downstream side 215D. The upstream side 215U of the barrel 212 may be provided with a material supply port 216, which may include a hopper or other material supply structure for supplying the batch composition mixture 210 to the extrusion molding machine 200. A cartridge assembly 217 containing a honeycomb extrusion die 218 is provided downstream 215D for extruding the batch mixture 210 into a desired shape such as a base honeycomb body 100G. Before the plasticized batch composition mixture 210 reaches the honeycomb extrusion die 218, other structures such as an entirely open cavity, a screen 220, or a homogenizer 222 may be present before the honeycomb extrusion die 218 to facilitate the formation of a stable plug-type flow front.

[0063] As further shown in Figure 2, a pair of extrusion screws 224 can be rotatably mounted within the barrel 212. The screws 224 may be arranged approximately parallel to each other as shown, but may be arranged at various angles to each other as desired. The screws 224 may also be coupled to a drive mechanism 220 located outside the barrel 212 for rotation of the screws 224 in the same or different directions. It should be understood that both screws 224 may be coupled to a single drive mechanism 220 as shown, or to independent drive mechanisms (not shown). The screws 224 operate to move the batch composition mixture 210 longitudinally 215 through the chamber 214 by pumping and further mixing. Further support structures may be provided to support the screws 224 at their ends and / or along their length. Such support structures may include perforations or holes through which the batch composition mixture 210 can flow.

[0064] Figure 2 further shows the extrusion machine 200 with the base material 100G being extruded from it. The extrusion machine cartridge 217 may include extrusion hardware such as a honeycomb extrusion die 218 and a skin-forming mask 226. The base material 100G is extruded from the extrusion machine 200, and in some embodiments, a skin 106 surrounding the multiple walls 102 is also formed along the multiple walls 102 during the extrusion process. The honeycomb body 100G is then cut to a certain length by a cutting element 228 and placed on a tray 230. The tray 230 can be, for example, one of those described in U.S. Patent No. 9,440,373; U.S. Patent No. 9,085,089; or U.S. Patent No. 8,407,915.

[0065] Cutting can be achieved by wire cutting, saw cutting with a band saw or reciprocating saw, or other cutting methods. The tray 232 can be fed into a dryer, for example, as described in U.S. Patent Nos. 9,038,284, 9,335,093, 7,596,885, and 6,259,078. Any preferred drying method, such as RF drying, microwave drying, oven drying, or a combination thereof, can be used. In some embodiments, the substrate honeycomb 100G can be cut from a log, for example, after drying, from which multiple honeycomb bodies are supplied.

[0066] After drying, the base material 100G can be fired under conditions effective for converting the base honeycomb into a ceramic body 100 containing cordierite, indialite, and imitation titanite, as well as other crystalline phases.

[0067] Batch composition The batch composition mixture may include: inorganic components comprising a magnesia source, an alumina source, a silica source, and a titania source; and porosity-forming agents (e.g., starch and / or graphite), which may further have the particle size and particle size distribution, as well as width (dBp), as described in Table 1 below.

[0068] [Table 1]

[0069] For this purpose, where referred to herein, all particle sizes are measured using laser diffraction techniques and a Microtrac particle size analyzer, with the exception of dispersible alumina (AlOH), whose properties were defined by the supplier.

[0070] Magnesia source For example, the magnesia source can be any suitable compound that can provide a magnesium oxide useful for forming a cordierite-indialite-laminated titanite structured crystalline phase composition, not limited to but exemplifying. For example, the magnesia source can be selected as a talc source, or magnesium hydroxide, or a combination thereof. For example, the talc source can be calcined or uncalcined talc. Optionally, the magnesia source can be one or more of MgO, Mg(OH)2, MgCO3, MgAl2O4, Mg2SiO4, MgSiO3, MgTiO3, Mg2TiO4, MgTi2O5. Alternatively, the magnesia source can be one or more of forsterite, olivine, chlorite, and serpentine. When the magnesia source is talc, it has a particle median diameter (d) of about 6 μm to about 25 μm. p50 ) can have, and also dB p We can set it to ≤2.2, where dB p is the width coefficient, and (d p90 -d p10 ) / d p50 The magnesia source can be composed of 25% to 40% by weight, based on 100% of the total weight of inorganic substances present in the batch composition mixture 210.

[0071] Alumina source The alumina source can be any suitable compound that can provide an aluminum oxide useful for forming a cordierite-indialite-ply-titaniumite structured crystalline phase composition, not limited to but exemplifying. The alumina source can be selected from alumina-forming sources such as corundum, aluminum hydroxide (or alumina hydroxide) such as Al(OH)3, dispersible alumina such as boehmite that can form a colloidal suspension, diaspore, or transition alumina such as γ-alumina or ρ-alumina. Alternatively, the alumina source can be a compound of aluminum with another metal oxide, such as MgAl2O4, Al2TiO5, mullite, kaolin, calcined kaolin, pyrophyllite, kyanite, or chlorite. In some embodiments, the median grain size (d p50The particle size can be approximately 7.0 μm or less, and can range from approximately 0.5 μm to approximately 7.0 μm. The alumina source can consist of 25% to 40% by weight, based on 100% of the total weight of inorganic substances present in the batch composition mixture 210.

[0072] Silica source The silica source can be any suitable compound that can provide silica oxides useful for forming cordierite-indialite-plicatite crystalline phase compositions, not limited to but exemplifying. The silica source can be selected from silica sources such as SiO2 powder, including, for example, quartz, cryptocrystalline quartz, fused silica, diatomaceous earth silica, low-alkali zeolite, colloidal silica, or combinations thereof. Furthermore, the silica source can also be provided as a compound with magnesium and / or aluminum, including, for example, talc, cordierite, chlorite, kaolin, kyanite, etc. In the embodiment, the median particle size (d) of the silica source is... 50 The particle size can be approximately 4 μm to approximately 30 μm. The silica source can consist of 15% to 30% by weight, based on 100% of the total weight of inorganic matter present in the batch composition mixture 210.

[0073] Titania source The titania source can be provided as TiO2 powder. The median particle size (d) is shown in Table 1. p50 ) and / or titania powder having a particle size distribution can be used. For example, the titania source may have a median particle size of 0.25 μm to 0.45 μm. Furthermore, the titania source may have a width coefficient dB p ≤2.0, and furthermore, dB p ≤1.5 (where dB) p =(d p90 -d p10 ) / d p50 It can have a particle size distribution that is ( ).

[0074] Pore-forming agent To achieve a relatively high average bulk porosity (%P≧50%), the batch composition mixture 210 may contain a pore-forming agent to help adjust the average bulk porosity and, optionally, the pore size distribution of the ceramic body 100. The pore-forming agent is a transient material that adjusts the desired coarse pore median diameter (d) in the ceramic body 100. 50 To obtain the desired high bulk porosity, which can be linked to ), the material evaporates or vaporizes by combustion during the drying and / or heating of 100G of substrate. Suitable porosity-forming agents include, but are not limited to, carbon; graphite; starch; wood, bark, or nut powder; polymers such as polyethylene beads; and combinations thereof. Examples of starches include corn starch, rice starch, pea starch, sago starch, potato starch, etc. Other suitable porosity-forming agents may also be used. When using a specific porosity-forming agent such as potato starch, a relatively coarse (e.g., d p50 Using a larger source of talc, alumina, and / or silica can reduce df.

[0075] Relatively high porosity and relatively large d 50 Exemplary embodiments that help provide useful combinations include combinations of starch and graphite. For example, the pore-forming agent may include pea starch alone or in combination with graphite, or corn starch alone or in combination with graphite. The pore-forming agent is an additional component of about 25% by weight (SA) based on 100% by weight of the inorganic substances present in the batch composition mixture 210. pf ) ~ approx. 57% SA by weight pf It can be supplied in the following quantity. Based on 100% by weight of inorganic matter present in batch composition mixture 210, 20% by weight SA pf ~Approx. 47%SA by weight pf Starch and 20% by weight SA pf ~Approx. 47%SA by weight pf Embodiments including a combination with graphite offer high average bulk porosity and pore median diameter (d), which are useful for filtration applications. 50) can provide an excellent combination. The amount of pore-forming agent is w i ×Weight%SA pf It is calculated as / 100, and here w i This is the total weight of the inorganic raw materials.

[0076] Starch particles have a median diameter (d) of approximately 5 μm to 50 μm, and in other embodiments, approximately 8 μm to 30 μm. p50 ) can have a particle median diameter (d) of about 5 μm to 50 μm in some embodiments. p50 ) can have.

[0077] Organic binders The batch composition mixture 210 may contain an organic binder. The organic binder may be a cellulose ether binder, such as a hydrophobic modified cellulose ether binder. In some embodiments, the hydrophobic modified cellulose ether binder may be, but is not limited to, methylcellulose, ethyl hydroxyethylcellulose, hydroxybutyl methylcellulose, hydroxymethylcellulose, hydroxypropyl methylcellulose, hydroxyethyl methylcellulose, hydroxybutyl cellulose, hydroxyethylcellulose, hydroxypropyl cellulose, sodium carboxymethylcellulose, or combinations thereof. Methylcellulose and / or methylcellulose derivatives are particularly suitable as organic binders for use in the batch composition mixture 210, with methylcellulose and hydroxypropyl methylcellulose being excellent choices. The source of the cellulose ether is METHOCEL® cellulose products available from DOW® Chemical Co.

[0078] Some embodiments of the batch compositions disclosed in Tables 2A to 2E below may include methylcellulose (methylcellulose 1) and hydroxypropyl methylcellulose (methylcellulose 2). Other combinations of cellulose ether binders may include multiple cellulose ethers with different molecular weights. Alternatively, the combination of cellulose ethers may include multiple cellulose ethers having different hydrophobic groups or different concentrations of the same hydrophobic group, or combinations of other cellulose ethers. The different hydrophobic groups may, as non-limiting examples, be hydroxyethyl or hydroxypropyl. In some embodiments, the organic binder may be a combination of a hydroxyethyl methylcellulose binder and a hydroxypropyl methylcellulose binder. Other suitable combinations of organic binders may be used.

[0079] The organic binder may be provided in the batch composition in an amount of approximately 2.0% by weight SAP to 8.0% by weight SAP, and even more so, approximately 3.0% by weight SAP to approximately 5.0% by weight SAP, where SAP is based on the amount added to 100% of the total weight of inorganic substances and porosity-forming agents present in the batch composition mixture 210.

[0080] liquid vehicle In one or more embodiments, the batch composition mixture 210 comprises a liquid vehicle, which can be provided in a certain percentage LV% of the liquid vehicle as an addition to 100% by weight of the inorganic substances and pore-forming agents present in the batch. The LV% in the batch composition mixture 210 may be added to the batch composition mixture in an amount of about 15% by weight ≤ LV% ≤ 50% by weight, by addition to 100% by total weight of the inorganic substances and pore-forming agents present in the batch composition mixture 210.

[0081] During use, the liquid vehicle provides a medium for dissolving the organic binder, thereby providing plasticity to the batch composition mixture 210 and wetting the inorganic particles therein. The liquid vehicle can be an aqueous liquid, such as water or a water-miscible solvent. In one implementation, the liquid vehicle is water such as deionized water, but other solvents such as alcohols (e.g., methanol or ethanol) may also be used alone or in combination with water.

[0082] Processing aids Furthermore, the batch composition mixture 210 may also contain other processing aids such as plasticizers, surfactants, and / or oily lubricants. Non-limiting examples of surfactants that can be used as processing aids include C8-C8. 22 These are fatty acids and / or derivatives thereof. Further surfactant compositions that may be used with these fatty acids include C8-C 22 Aliphatic esters, C8~C 22 These are aliphatic alcohols and combinations thereof. Exemplary surfactants include: stearic acid, lauric acid, myristic acid, oleic acid, linoleic acid, and palmitic acid, and their derivatives; tall oil; stearic acid combined with ammonium lauryl sulfate; and all combinations thereof. In some exemplary embodiments, the surfactant is lauric acid, stearic acid, oleic acid, tall oil, or a combination thereof. In some embodiments, the amount of surfactant can be about 0.25% SA by weight to about 2% SA by weight, and in illustrated embodiments, about 0.5% SA by weight to 1.5% SA by weight.

[0083] Non-limiting examples of oily lubricants that can be used as processing aids include light mineral oil, corn oil, high molecular weight polybutene, polyol esters, blends of light mineral oil and wax emulsion, blends of paraffin wax in corn oil, or combinations of these with olefins. In some embodiments, the amount of oily lubricant can be about 0% SA by weight to about 10% SA by weight. In some exemplary embodiments, the oily lubricant can be present at a maximum of about 2% SA by weight. In some embodiments, no lubricant is used.

[0084] Inorganic batch powder components, organic binders, and pore-forming agents can be carefully blended with a liquid vehicle and one or more processing aids to impart plasticity and substrate strength to the plasticized batch composition mixture when molded onto a 100g substrate. When molding is carried out by extrusion, most typically, cellulose ether binders such as methylcellulose, hydroxypropylmethylcellulose, and / or combinations thereof function as temporary organic binders. Tall oil can function as a suitable processing aid. The inorganic batch components, organic binders, and pore-forming agents are typically mixed in a dry form and then mixed with a liquid vehicle (e.g., water) and one or more processing aids. The amount of liquid vehicle (e.g., water) may vary for each batch composition mixture, and is determined by preliminary testing of the extrudeability of a particular batch composition mixture and, if necessary, adjusting the LV% of the liquid vehicle to achieve appropriate plasticity and optimal handling characteristics for extrusion.

[0085] In addition to forming and shaping the substrate 100G from the plasticized batch composition mixture by extrusion, other suitable molding methods may be used. For example, the substrate 100G may be formed using a uniaxial or isostatic press, casting, and injection molding. For example, if the ceramic body 100 is embodied as a honeycomb, for example, as a pass-through substrate for a catalytic converter (e.g., a catalytic substrate), or as a sealed honeycomb for use in particulate wall flow filter applications, extrusion can be used. After drying the obtained substrate 100G, it can be fired in a furnace such as a gas or electric kiln under conditions effective for converting the substrate 100G into a ceramic body 100. After firing, the ceramic body 100 can be sealed as described herein to form a sealed ceramic body 100P.

[0086] firing In one or more embodiments, effective firing conditions for converting the substrate 100G into a ceramic body 100 include heating the substrate 100G to a maximum immersion temperature of 1,350°C to 1,410°C, and subsequently maintaining the above maximum immersion temperature for a sufficient immersion time to generate a cordierite-indialite-laminite crystalline phase composite structure. In some embodiments, the maximum immersion temperature can be 1,360°C to 1,400°C or 1,380°C to 1,395°C. The maximum immersion temperature is maintained for a sufficient immersion time to convert the substrate 100G into a ceramic body 100 having a cordierite-indialite-laminite crystalline phase composite structure. The immersion time can be, for example, about 6 hours to about 24 hours. After the immersion time, cooling is continued at a sufficiently low rate so as not to subject the ceramic body 100 to thermal shock.

[0087] Blindfold To obtain a sealed honeycomb body 100P for use in wall-flow particulate filter applications, portions of the cells of the ceramic honeycomb body 100 at the inlet end and / or face can be sealed as known in the art. This sealing may be performed at the end of the channel 104 and can be to a depth of approximately 3 mm to 20 mm, although this depth can be varied. In some embodiments, a portion of the channel 104 is sealed at the outlet end 105 rather than the inlet end 103 (e.g., the inlet channel), and another portion of the channel 104 is sealed at the inlet end 103 rather than the outlet end 105 (e.g., the outlet channel). Thus, each channel 104 is sealed only at one end in the fully sealed embodiment. In some embodiments, a sealing configuration can be provided such that all other channels 104 on a given face are sealed in a checkerboard pattern. However, other sealing patterns are possible, and not all channels 104 have to be sealed. Some channels 104 do not have to be sealed, i.e., they may be unsealed through channels. Preferred and non-limiting sealing materials and sealing processes are described, for example, in U.S. Patent No. 4,329,162; U.S. Patent No. 4,557,773; U.S. Patent No. 6,673,300; U.S. Patent No. 7,744,669; and U.S. Patent No. 7,922,951. Other preferred sealing methods, patterns, and types of sealing may be used.

[0088] Exemplary batch composition mixture The exemplary embodiments of this disclosure will now be further described with respect to specific batch composition mixtures, which are merely illustrative and not intended to be limiting. Tables 2A to 2E below provide several examples (E1 to E27) of batch composition mixtures 210 useful in forming a ceramic body 100 containing a cordierite-indialite-plytianeite structure composite ceramic. In particular, the exemplary batch mixtures 210 according to the embodiments described herein may include inorganic components, including a magnesia source, an alumina source, a silica source, and a titania source, which can be materials for a powdered particulate source, etc. Magnesia source can be provided in batch composition mixture in amounts of 20% to 42% by weight; alumina source in amounts of 25% to 40% by weight; silica source in amounts of 15% to 30% by weight; and titania source in amounts of 1% to 10% by weight, where the weight percentages of each of the magnesia source, alumina source, silica source, and titania source are all based on 100% of the total weight of inorganic substances present in the batch composition mixture 210, i.e., each inorganic component is added relative to 100%.

[0089] If the magnesia source is a talc source supplied to the batch composition mixture as a powdered fine-particle talc material, it can be provided, for example, according to one of the talc particle size distributions and materials shown in Table 1. The alumina source can be any preferred source of alumina and / or aluminum hydroxide, such as calcined alumina, hydrated alumina, or even those derived from clay such as kaolin clay. Other types of clay, such as halloysite or attapulgite, may also be used. In some embodiments, the alumina source may consist of: 11% to 33% by weight of calcined alumina fine-particle material; and 0% to 16% by weight of hydrated alumina, each based on 100% of the total weight of inorganic materials in the batch composition mixture 210.

[0090] The silica source can be derived from fine particle silica, clay such as kaolin clay, talc, or a combination thereof. The titania source can be any of the above-mentioned sources of fine particle titania (TiO2).

[0091] The batch composition mixture further contains 26% by weight of SA pf ~56wt%SA pf Furthermore, 35% SA by weight pf ~56wt%SA pf The pore-forming agent is provided in such quantities that wt% SA is the weight percentage of the added portion based on 100% of the total weight of inorganic substances in the batch composition mixture 210. In some embodiments, the pore-forming agent is 44 wt% SA. pf ~56wt%SA pf Only is provided. In further embodiments, the pore-forming agent is 44% by weight of SA pf ~51wt%SA pf This may include pea starch. Exemplary pea starch is as shown in Table 1 and / or as described elsewhere in this specification, with a median particle size (d 50 ) and particle size distribution can be present.

[0092] In some embodiments, the pore-forming agent includes starch alone or a combination of starch and graphite. For example, the pore-forming agent is 44% by weight SA pf ~46wt%SA pf Pea starch, and 9% by weight SA pf ~11wt%SA pf Contains graphite, here by weight %SA pf This is the weight percentage of the added portion based on 100% of the total weight of inorganic substances in the batch composition mixture 210.

[0093] [Table 2A]

[0094] [Table 2B]

[0095] [Table 2C]

[0096] [Table 2D]

[0097] [Table 2E]

[0098] Tables 3A to 3G below show the nominal oxide chemical composition, processing details, microstructure geometry and properties, and the composition of various phases as phase fractions in weight percent (W%) for exemplary ceramic bodies E1A to E28 after firing, which were produced from batch composition mixture 210 using the raw materials in Table 1 and the batch composition mixtures defined in Tables 2A to 2E.

[0099] Examples E1A to E28 in Tables 3A to 3G, corresponding to E1 to E28 in Tables 2A to 2E, have axial lengths of approximately 200 mm to 305 mm, a nominal diameter of 54 mm in the transverse cross-section, and a cell density of 46.6 cells / cm³, respectively. 2 These were obtained by extruding honeycomb substrates 100G having a wall thickness of 0.20 mm to 0.23 mm. These honeycomb substrates 100G were made from various batch materials listed in Tables 2A to 2E, and then fired in an electric furnace under the listed firing conditions. The maximum immersion temperature (°C) and immersion time (hr) are indicated.

[0100] The calculated oxide weight percentages for various sources are shown. The phase fractions of the various phases present in the cordierite-indialite-citrate (CID) composite ceramic are also shown. For example, E2 contains cordierite, indialite, spinel, enstatite, armalcolite as a citrate structure, rutile, and amorphous phases. The phase fractions for all examples E1A to E28 were determined by the Rietveld method and X-ray diffraction.

[0101] [Table 3A]

[0102] [Table 3B]

[0103] [Table 3C]

[0104] [Table 3D]

[0105] [Table 3E]

[0106] [Table 3F]

[0107] [Table 3G]

[0108] The pore size distribution of ceramic body 100 was investigated by mercury penetration porosimetry using an Autopore® IV 9520 porosimemeter. In this measurement system, the pressure is increased so that mercury penetrates relatively narrow pore channels and fills the increased pore volume until a critical pressure is reached at which mercury spreads throughout the entire specimen.

[0109] Thermal expansion was measured for a bar-shaped sample with dimensions of approximately 0.25 inches × 0.25 inches × 2 inches (0.64 × 0.64 × 5.1 cm) while heating from room temperature to 1,000°C at a rate of 4°C / min and then cooling to room temperature (RT). For the reported data, thermal expansion was provided in the axial direction of the honeycomb body 100 by orienting the long axis of the test bar toward the honeycomb channel 104. The average coefficient of thermal expansion from room temperature (RT) to 800°C is defined as L(800°C) - L(25°C) / 775°C.

[0110] The modulus of elasticity (E) was measured by bending resonance frequency using a bar-shaped sample with dimensions of 5 inches × 1 inch × 0.5 inches (12.7 × 2.54 × 1.27 cm) and its long axis oriented in the direction of the honeycomb channel 104. The sample was heated to 1200°C and then cooled again to room temperature. For each temperature, the modulus of elasticity was derived directly from the resonance frequency by referring to ASTM C 1198-01 and normalized with respect to the geometry and weight of the sample.

[0111] Figures 4A–4C show scanning electron microscope (SEM) images of polished and fired products from Examples E9, E7C, and E18, which show magnified views of the phase distribution, where the cordierite and indialite phases are dark gray, the pores are black, and the quasi-titanite structure phase is light gray. The phases present in ceramic body 100 were identified by X-ray diffraction (XRD). A Phillips X'Pert diffraction system with an X'Celerator fast detector was used. High-resolution spectra were acquired, typically at 15°–100°(2θ). The percentage of each phase was quantified using the Rietveld method.

[0112] Figure 5 shows a method for producing a ceramic body 100. Method 500 includes the step in 502 of providing an inorganic component comprising 20% ​​to 42% by weight of a magnesia source, 25% to 40% by weight of an alumina source, 15% to 30% by weight of a silica source, and 1% to 10% by weight of a titania source, where the weight percentages of the magnesia source, alumina source, silica source, and titania source are based on 100% of the total weight of the inorganic material present.

[0113] Manufacturing method 500 further involves, in 504, the inorganic component being an organic binder, 26% by weight SA pf ~56wt%SA pf The step includes mixing a pore-forming agent and a liquid vehicle to form a batch composition mixture, where % SA by weight. pf This is the weight percentage of the additional component based on 100% of the total weight of the inorganic substances mentioned above.

[0114] The manufacturing method 500 further includes, in 506, a step of molding the batch composition mixture to form a substrate (e.g., substrate 100G), and in 508, a step of drying the substrate 100G as described herein. The step of molding the batch composition mixture 210 to form a substrate 100G may include a step of extruding the batch composition mixture 210 through an extrusion die 218 to form a substrate honeycomb. Optionally, the molding step may be carried out by any other preferred method.

[0115] The manufacturing method 500 further includes the step in 510 of firing the substrate under conditions effective for converting the substrate into a ceramic body (e.g., ceramic body 100) comprising a crystalline phase containing cordierite and indialite in a total weight percentage of at least 85 wt% and a crystalline platylithite structure phase of up to 10 wt%. The crystalline phase containing the platylithite structure phase may, in some embodiments, include armacolite. However, other platylithite structure phases can also be provided. In some embodiments, the firing conditions effective for converting the substrate (e.g., substrate 100G) into a ceramic body 100 include heating the substrate 100G at an immersion temperature of 1350°C to 1410°C and maintaining the immersion temperature for a sufficient immersion time to convert the substrate 100G into a ceramic body 100.

[0116] It will be apparent to those skilled in the art that various modifications and changes can be made to the various embodiments disclosed herein without departing from the scope of this disclosure. Accordingly, this disclosure is intended to encompass such modifications and variations of the disclosed embodiments, insofar as they fall within the scope of the claims and their equivalents.

[0117] Preferred embodiments of the present invention are described below in separate sections.

[0118] Embodiment 1 %P ≥ 50% (where %P is the average bulk volume porosity); df ≤ 0.36 (where df is (d 50 -d 10 ) / d 50 (is) and; It comprises a crystalline phase containing cordierite and indialite in a total weight percentage of at least 85% by weight; A ceramic body comprising a crystalline phase containing a pseudo-titaniumite structure, up to 10% by weight, The above ceramic material, when expressed in weight percentage based on oxide: 1% to 11% by weight of titania, and 89% to 99% by weight of MgO, Al2O3, and SiO2 (where the relative weight ratios of MgO:Al2O3:SiO2 are within the fields defined by 15.6:34.0:50.4, 12.6:34.0:53.4, 13.9:30.7:55.4, and 16.9:30.7:52.4); or 2.5% to 11% titania, and 89% to 97.5% by weight of MgO, Al2O3, and SiO2 (where the relative weight ratios of MgO:Al2O3:SiO2 are within the fields defined by 15.6:34.0:50.4, 12.6:34.0:53.4, 12.0:35.7:52.3, and 15.0:35.7:49.3). A ceramic body containing [ceramic material].

[0119] Embodiment 2 Microcrack index Nb3 Nb 3 A ceramic body according to Embodiment 1, wherein the coefficient is ≥ 0.10.

[0120] Embodiment 3 A ceramic body according to Embodiment 1, wherein %P ≥ 55%.

[0121] Embodiment 4 A ceramic body according to Embodiment 1, wherein %P ≥ 60%.

[0122] Embodiment 5 A ceramic body according to Embodiment 1, wherein %P ≥ 65%.

[0123] Embodiment 6 A ceramic body according to Embodiment 1, wherein 50% ≤ %P ≤ 72%.

[0124] Embodiment 7 A ceramic body according to Embodiment 1, wherein 60% ≤ %P ≤ 72%.

[0125] Embodiment 8 A ceramic body according to Embodiment 1, wherein 65% ≤ %P ≤ 72%.

[0126] Embodiment 9 A ceramic body according to Embodiment 1, wherein df ≤ 0.32.

[0127] Embodiment 10 A ceramic body according to Embodiment 1, wherein df ≤ 0.25.

[0128] Embodiment 11 A ceramic body according to Embodiment 1, wherein df ≤ 0.22.

[0129] Embodiment 12 A ceramic body according to Embodiment 1, wherein df ≤ 0.20.

[0130] Embodiment 13 A ceramic body according to Embodiment 1, wherein df ≤ 0.18.

[0131] Embodiment 14 A ceramic body according to Embodiment 1, wherein df ≤ 0.17.

[0132] Embodiment 15 A ceramic body according to Embodiment 1, wherein 0.16 ≤ df ≤ 0.30.

[0133] Embodiment 16 A ceramic body according to Embodiment 1, wherein 0.16 ≤ df ≤ 0.25.

[0134] Embodiment 17 A ceramic body according to Embodiment 1, wherein 0.16 ≤ df ≤ 0.22.

[0135] Embodiment 18 A ceramic body according to Embodiment 1, wherein 0.16 ≤ df ≤ 0.20.

[0136] Embodiment 19 A ceramic body according to Embodiment 1, wherein dB ≤ 0.85.

[0137] Embodiment 20 A ceramic body according to Embodiment 1, wherein the dB ≤ 0.70.

[0138] Embodiment 21 A ceramic body according to Embodiment 1, wherein dB ≤ 0.60.

[0139] Embodiment 22 7μm≦d 50 ≤20μm (where d 50 The ceramic body according to Embodiment 1, wherein (where is the pore median diameter of the ceramic body).

[0140] Embodiment 23 10 μm ≤ d 50 ≤20μm (where d 50 The ceramic body according to Embodiment 22, wherein (where is the pore median diameter of the ceramic body).

[0141] Embodiment 24 12 μm ≤ d 50 ≤20μm (where d 50 The ceramic body according to Embodiment 22, wherein (where is the pore median diameter of the ceramic body).

[0142] Embodiment 25 When measured between 25°C and 800°C, CTE ≤ 14 × 10⁻¹⁴ -7 A ceramic body according to Embodiment 1, having a temperature of / ℃ (where CTE is the coefficient of thermal expansion).

[0143] Embodiment 26 CTE ≤ 13 × 10 -7 A ceramic body according to embodiment 25, wherein the temperature is / ℃.

[0144] Embodiment 27 CTE ≤ 12 × 10 -7 A ceramic body according to embodiment 25, wherein the temperature is / ℃.

[0145] Embodiment 28 CTE ≤ 10 × 10 -7 A ceramic body according to embodiment 25, wherein the temperature is / ℃.

[0146] Embodiment 29 CTE ≤ 9 × 10 -7 A ceramic body according to embodiment 25, wherein the temperature is / ℃.

[0147] Embodiment 30 3 x 10 -7 / ℃≦CTE≦14×10 -7 A ceramic body according to embodiment 25, wherein the temperature is / ℃.

[0148] Embodiment 31 3 x 10 -7 / ℃≦CTE≦12×10 -7 A ceramic body according to embodiment 25, wherein the temperature is / ℃.

[0149] Embodiment 32 50% ≤ %P ≤ 72%; 7μm≦d50 ≤20μm (where d 50 (where is the pore median diameter); 0.16 ≤ df ≤ 0.36; 3 x 10 -7 / K≦CTE≦14×10 -7 A ceramic body according to Embodiment 1, wherein the value is / K.

[0150] Embodiment 33 60% ≤ %P ≤ 72%; 10 μm ≤ d 50 ≤20μm (where d 50 (where is the pore median diameter); 0.16 ≤ df ≤ 0.25; 3 x 10 -7 / ℃≦CTE≦13×10 -7 The ceramic body according to Embodiment 1, wherein the temperature is / ℃ (where CTE is the coefficient of thermal expansion of the ceramic body when measured between 25℃ and 800℃).

[0151] Embodiment 34 60% ≤ %P ≤ 72%; 12 μm ≤ d 50 ≤20μm (where d 50 (where is the pore median diameter of the above ceramic body); 0.16 ≤ df ≤ 0.20; 3 x 10 -7 / K≦CTE≦12×10 -7 The ceramic body according to Embodiment 1, wherein the coefficient of thermal expansion of the ceramic body is / K (where CTE is the coefficient of thermal expansion of the ceramic body when measured at 25°C to 800°C).

[0152] Embodiment 35 60% ≤ %P ≤ 72%; 13 μm ≤ d 50 ≤20μm (where d 50 (where is the pore median diameter of the above ceramic body); 0.16 ≤ df ≤ 0.18; 3 x 10 -7 / K≦CTE≦12×10 -7The ceramic body according to Embodiment 1, wherein the coefficient of thermal expansion of the ceramic body is / K (where CTE is the coefficient of thermal expansion of the ceramic body when measured at 25°C to 800°C).

[0153] Embodiment 36 The ceramic body according to Embodiment 1, wherein the crystalline phase of cordierite and indialite is 85% to 92% by weight.

[0154] Embodiment 37 The ceramic body according to Embodiment 1, wherein the above-mentioned crystalline phase of cordierite is 53% to 78% by weight.

[0155] Embodiment 38 The ceramic body according to Embodiment 1, wherein the above-mentioned crystalline phase of Indialite is 15% to 35% by weight.

[0156] Embodiment 39 The above-described pseudo-titanium plate structure is a ceramic body according to Embodiment 1, comprising a crystalline phase of armacolite.

[0157] Embodiment 40 The ceramic body according to Embodiment 39, wherein the above-mentioned crystalline phase of armalcolite is 2% to 8% by weight.

[0158] Embodiment 41 A ceramic body according to Embodiment 1, comprising 1.5% to 3% by weight of a crystalline mullite phase.

[0159] Embodiment 42 A ceramic body according to Embodiment 1, comprising less than 1.0% by weight of a crystalline phase of rutile.

[0160] Embodiment 43 A ceramic body according to Embodiment 1, comprising less than 7% by weight of an amorphous phase.

[0161] Embodiment 44 The ceramic body according to Embodiment 1, wherein the titania oxide concentration is 1% to 6% by weight.

[0162] Embodiment 45 The ceramic body according to Embodiment 44, wherein the oxide concentration of the above-mentioned titania is 2% by weight to 6% by weight.

[0163] Embodiment 46 The ceramic body according to Embodiment 1, wherein the oxide concentration of the above-mentioned magnesia is 12% by weight to 17% by weight.

[0164] Embodiment 47 The ceramic body according to Embodiment 1, comprising 2% by weight to 6% by weight of titania, and 94% by weight to 98% of MgO, Al2O3, and SiO2 (where the relative weight ratio of MgO:Al2O3:SiO2 is within the field defined by 14.3:34.9:50.8; 13.3:34.9:51.8; 14.3:32.3:53.4; and 15.3:32.3:52.4).

[0165] Embodiment 48 The ceramic body according to Embodiment 1, comprising a honeycomb body.

[0166] Embodiment 49 The ceramic body according to Embodiment 48, wherein the above-mentioned honeycomb body comprises a matrix of a connected porous wall.

[0167] Embodiment 50 The ceramic body according to Embodiment 49, wherein the matrix of the above-mentioned connected porous wall has a lateral wall thickness of 0.05 mm to 0.41 mm.

[0168] Embodiment 51 The matrix of the above-mentioned connected porous wall has a cell density of 15.5 cells / cm 2 ~62 cells / cm 2 The ceramic body according to Embodiment 49.

[0169] Embodiment 52 A ceramic body comprising a crystalline phase containing cordierite and indialite with a total weight percentage of 85% to 92% and a second crystalline phase with a pseudo-titanium plate structure containing armacolite up to 10% by weight, The above ceramic body contains, when expressed as an oxide-based weight percentage, 1% to 11% by weight of titania, and 89% to 99% by weight of MgO, Al2O3, and SiO2 (where the relative weight ratios of MgO:Al2O3:SiO2 are within the fields defined by 15.6:34.0:50.4, 12.6:34.0:53.4, 13.9:30.7:55.4, and 16.9:30.7:52.4); 55% ≤ %P ≤ 72%; 8μm≦d 50 ≤20μm (where d 50 (where is the pore median diameter); 0.16 ≤ df ≤ 0.32 (where df is (d 50 -d 10 ) / d 50 (is) and; 3 × 10⁻⁶ at 25°C to 800°C -7 / ℃≦CTE≦14×10 -7 A ceramic body with a temperature of / ℃.

[0170] Embodiment 53 A ceramic body comprising a crystalline phase containing cordierite and indialite with a total weight percentage of 85% to 92% and a second crystalline phase with a pseudo-titanium plate structure containing armacolite up to 10% by weight, The above ceramic body contains, when expressed as an oxide-based weight percentage, 2.5% to 11% titania, and 89% to 97.5% by weight of MgO, Al2O3, and SiO2 (where the relative weight ratios of MgO:Al2O3:SiO2 are within the fields defined by 15.6:34.0:50.4, 12.6:34.0:53.4, 12.0:35.7:52.3, and 15.0:35.7:49.3); 55% ≤ %P ≤ 72%; 8μm≦d 50 ≤20μm (where d50 (where is the pore median diameter); 0.16 ≤ df ≤ 0.32 (where df is (d 50 -d 10 ) / d 50 (is) and; 3 × 10⁻⁶ at 25°C to 800°C -7 / ℃≦CTE≦14×10 -7 A ceramic body with a temperature of / ℃.

[0171] Embodiment 54 When expressed as a weight percentage based on oxides: 1% to 11% by weight of titania, and 89% to 99% by weight of MgO, Al2O3, and SiO2 (where the relative weight ratios of MgO:Al2O3:SiO2 are within the fields defined by 15.6:34.0:50.4, 12.6:34.0:53.4, 13.9:30.7:55.4, and 16.9:30.7:52.4); or 2.5% to 11% titania, and 89% to 97.5% by weight of MgO, Al2O3, and SiO2 (where the relative weight ratios of MgO:Al2O3:SiO2 are within the fields defined by 15.6:34.0:50.4, 12.6:34.0:53.4, 12.0:35.7:52.3, and 15.0:35.7:49.3). A batch composition mixture comprising a magnesia source, an alumina source, a silica source, and a titania source.

[0172] Embodiment 55 20% to 42% by weight of the above magnesia source; 25% to 40% by weight of the above alumina source; 15% to 30% by weight of the above silica source; and 1% to 10% by weight of titania source Includes, The batch composition mixture according to Embodiment 54, wherein the above weight percentages of the above magnesia source, alumina source, silica source, and titania source are all based on 100% of the total weight of inorganic substances present in the batch composition mixture.

[0173] Embodiment 56 The alumina source is, based on the total weight of the inorganic substances in the batch composition mixture, respectively: 20 wt% to 35 wt% alumina; and 0 wt% to 16 wt% hydrated alumina The batch composition mixture according to Embodiment 54, containing

[0174] Embodiment 57 Containing 26 wt% SA to 56 wt% SA pore former, wt% SA is the weight percentage of the additional component based on the total weight of the inorganic substances in the batch composition mixture. The batch composition mixture according to Embodiment 54

[0175] Embodiment 58 The pore former is provided within the range of 35 wt% SA to 56 wt% SA. The batch composition mixture according to Embodiment 57

[0176] Embodiment 59 The pore former contains pea starch provided within the range of 35 wt% SA to 51 wt% SA. The batch composition mixture according to Embodiment 57

[0177] Embodiment 60 The pore former contains pea starch within the range of 36 wt% SA to 46 wt% SA and graphite within the range of 9 wt% SA to 11 wt% SA. The batch composition mixture according to Embodiment 57

[0178] Embodiment 61 The pore former contains only starch or a combination of starch and graphite. The batch composition mixture according to Embodiment 57

[0179] Embodiment 62 A method for manufacturing a ceramic body, wherein The method is: 20 wt% to 42 wt% magnesia source, 25 wt% to 40 wt% alumina source, A silica source of 15% to 30% by weight, and Titania source of 1% to 10% by weight, A step of providing an inorganic component comprising the above-mentioned magnesia source, alumina source, silica source, and titania source, wherein the above-mentioned weight percentages of each are based on 100% of the total weight of the inorganic material present; The above inorganic components are 26% by weight of SA pf ~56wt%SA pf The step of mixing the pore-forming agent and liquid vehicle to form a batch composition mixture, wherein the weight % SA pf This is a step, which is the weight percentage of the added amount based on 100% of the total weight of the inorganic substances mentioned above; The step of molding the above batch composition mixture to form a base material; and A step of firing the above-mentioned substrate under conditions effective for converting it into a ceramic body comprising a crystalline phase containing cordierite and indialite in a total weight percentage of at least 85% by weight, and a crystalline phase containing a quasi-titaniumite structure in a total weight percentage of up to 10% by weight. Methods that include...

[0180] Embodiment 63 The method according to Embodiment 62, wherein the above firing conditions effective for converting the above substrate into a ceramic body include heating the above substrate at an immersion temperature of 1350°C to 1410°C, and maintaining the above immersion temperature for a sufficient immersion time to convert the above substrate into a ceramic body.

[0181] Embodiment 64 The above-described pseudo-titanium plate structure is the method according to Embodiment 62, which includes a crystalline phase of armacolite.

[0182] Embodiment 65 The method according to Embodiment 62, wherein the step of molding the batch composition mixture to form the substrate includes extruding the batch composition mixture through an extrusion die to form a substrate honeycomb body.

[0183] Embodiment 66 %P ≥ 50% (where %P is the average bulk volume porosity); df ≤ 0.36 (where df is (d 50 -d 10 ) / d 50 (is) and; It comprises a crystalline phase containing cordierite and indialite in a total weight percentage of at least 85% by weight; A ceramic body comprising a crystalline phase containing a pseudo-titaniumite structure, up to 10% by weight, The ceramic body, when expressed in weight percentage based on oxide: 1% to 11% by weight of titania, and 89% to 99% by weight of MgO, Al2O3, and SiO2 (where the relative weight ratios of MgO:Al2O3:SiO2 are within the fields defined by 15.6:34.0:50.4, 12.6:34.0:53.4, 13.9:30.7:55.4, and 16.9:30.7:52.4); or 2.5% to 11% titania, and 89% to 97.5% by weight of MgO, Al2O3, and SiO2 (where the relative weight ratios of MgO:Al2O3:SiO2 are within the fields defined by 15.6:34.0:50.4, 12.6:34.0:53.4, 12.0:35.7:52.3, and 15.0:35.7:49.3). A ceramic body containing [ceramic material].

[0184] Embodiment 67 7μm≦d 50 ≤20μm (where d 50 The ceramic body according to embodiment 66, wherein (where is the pore median diameter of the ceramic body).

[0185] Embodiment 68 50% ≤ %P ≤ 72%; 7μm≦d 50 ≤20μm (where d 50 (where is the pore median diameter); 0.16 ≤ df ≤ 0.36; 3 x 10 -7 / K≦CTE≦14×10 -7 A ceramic body according to embodiment 66, wherein the value is / K.

[0186] Embodiment 69 60% ≤ %P ≤ 72%; 10 μm ≤ d 50 ≤20μm (where d 50 (where is the pore median diameter); 0.16 ≤ df ≤ 0.25; 3 x 10 -7 / ℃≦CTE≦13×10 -7 The ceramic body according to Embodiment 66, wherein the temperature is / ℃ (where CTE is the coefficient of thermal expansion of the ceramic body when measured at 25℃ to 800℃).

[0187] Embodiment 70 A ceramic body according to Embodiment 66, comprising 2% to 6% by weight of titania, and 94% to 98% by weight of MgO, Al2O3, and SiO2 (where the relative weight ratio of MgO:Al2O3:SiO2 is within the fields defined by 14.3:34.9:50.8; 13.3:34.9:51.8; 14.3:32.3:53.4; and 15.3:32.3:52.4).

[0188] Embodiment 71 A method for manufacturing ceramic bodies, The aforementioned method is: 20% to 42% by weight of magnesia source, Alumina source of 25% to 40% by weight, A silica source of 15% to 30% by weight, and Titania source of 1% to 10% by weight, A step of providing an inorganic component comprising the following, wherein the weight percentages of the magnesia source, the alumina source, the silica source, and the titania source are all based on 100% of the total weight of the inorganic material present; The aforementioned inorganic component is 26% by weight SA pf ~56wt%SA pfThe step of mixing the pore-forming agent and liquid vehicle to form a batch composition mixture, wherein the weight % SA pf This is a step, where the additional weight percentage is based on 100% of the total weight of the inorganic material; The step of molding the batch composition mixture to form a base material; and A step of firing the substrate under conditions effective for converting the substrate into a ceramic body comprising a crystalline phase containing cordierite and indialite in a total weight percentage of at least 85% by weight, and a crystalline phase containing a quasi-titaniumite structure in a total weight percentage of up to 10% by weight. Methods that include... [Explanation of Symbols]

[0189] 100 ceramic body 100G base material, base material honeycomb structure 100P Sealed Ceramic Honeycomb Body 102 Porous wall 103 First end, entrance end 104, 104L, 104S Channel 105 Second end, exit end 106 Epidermis 200 Extrusion Molding Machines 210 Plasticized batch composition mixture 212 barrels 214 Chamber 215 Longitudinal direction 215D Downstream 215U upstream side 216 Material supply ports 217 Cartridge Assembly, Extrusion Molding Machine Cartridge 218 Honeycomb Extrusion Dies 220 screens 222 Homogenizer 224 Extrusion Screw 226 Epidermal formation mask 228 cutting elements 230 trays

Claims

1. %P ≥ 50% (where %P is the average bulk volume porosity); df ≤ 0.36 (where df is (d ５０ -d １０ ) / d ５０ (is) and; The material comprises a crystalline phase containing cordierite and indialite, with cordierite making up 53% to 78% by weight, indialite making up 15% to 35% by weight, and the total weight percentage being at least 85% by weight; A ceramic body comprising a crystalline phase containing a pseudo-titaniumite structure, up to 10% by weight, The aforementioned ceramic body, expressed in weight percentage based on oxide, is: 1 wt% to 11 wt% of titania, and 89 wt% to 99 wt% of MgO, Al ２ O ３ , and SiO ２ (where the relative weight ratio of MgO:Al ２ O ３ :SiO ２ is within the field defined by 15.6:34.0:50.4, 12.6:34.0:53.4, 13.9:30.7:55.4, and 16.9:30.7:52.4); or 2.5% to 11% titania, and 89% to 97.5% by weight of MgO and Al ２ O ３ , and SiO ２ (Here MgO:Al ２ O ３ SiO ２ (The relative weight ratios are within the fields defined by 15.6:34.0:50.4, 12.6:34.0:53.4, 12.0:35.7:52.3, and 15.0:35.7:49.3.) A ceramic body containing [ceramic material].

2. 7 μm ≤ d ５０ ≤20 μm (where d ５０ The ceramic body according to claim 1, wherein ( is the median diameter of the pores of the ceramic body).

3. 50% ≤ %P ≤ 72%; 7 μm ≤ d ５０ ≤20 μm (where d ５０ (where is the pore median diameter); 0.16 ≤ df ≤ 0.36; 3 x 10 －７ K ≤ CTE ≤ 14 × 10 －７ A ceramic body according to claim 1, wherein the value is K.

4. 60% ≤ %P ≤ 72%; 10 μm ≤ d ５０ ≤20 μm (where d ５０ (where is the pore median diameter); 0.16 ≤ df ≤ 0.25; 3 x 10 －７ / ℃≦CTE≦13×10 －７ The ceramic body according to claim 1, wherein the coefficient of thermal expansion of the ceramic body is / °C (where CTE is the coefficient of thermal expansion of the ceramic body when measured at 25°C to 800°C).

5. 2% to 6% by weight of titania, and 94% to 98% by weight of MgO, Al ２ O ３ , and SiO ２ (Here MgO:Al ２ O ３ SiO ２ The ceramic body according to claim 1, wherein the relative weight ratios are within the fields defined by 14.3:34.9:50.8; 13.3:34.9:51.8; 14.3:32.3:53.4; and 15.3:32.3:52.

4.

6. The ceramic body according to claim 1, wherein the crystalline phase containing the pseudo-titaniumite structure contains armacolite.

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