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JP2024155787A - Honeycomb Filter - Google Patents

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JP2024155787A
JP2024155787A JP2024065167A JP2024065167A JP2024155787A JP 2024155787 A JP2024155787 A JP 2024155787A JP 2024065167 A JP2024065167 A JP 2024065167A JP 2024065167 A JP2024065167 A JP 2024065167A JP 2024155787 A JP2024155787 A JP 2024155787A
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partition walls
honeycomb filter
pore
honeycomb
partition wall
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佑基 高室
Yuki Takamuro
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NGK Insulators Ltd
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    • BPERFORMING OPERATIONS; TRANSPORTING
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    • B01D46/24Particle separators, e.g. dust precipitators, using rigid hollow filter bodies
    • B01D46/2403Particle separators, e.g. dust precipitators, using rigid hollow filter bodies characterised by the physical shape or structure of the filtering element
    • B01D46/2418Honeycomb filters
    • B01D46/2425Honeycomb filters characterized by parameters related to the physical properties of the honeycomb structure material
    • B01D46/2429Honeycomb filters characterized by parameters related to the physical properties of the honeycomb structure material of the honeycomb walls or cells
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    • B01D53/34Chemical or biological purification of waste gases
    • B01D53/92Chemical or biological purification of waste gases of engine exhaust gases
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    • B01J35/50Catalysts, in general, characterised by their form or physical properties characterised by their shape or configuration
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
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    • F01N3/00Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/02Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust
    • F01N3/021Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters
    • F01N3/022Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters characterised by specially adapted filtering structure, e.g. honeycomb, mesh or fibrous
    • F01N3/0222Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters characterised by specially adapted filtering structure, e.g. honeycomb, mesh or fibrous the structure being monolithic, e.g. honeycombs
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    • F01N3/00Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/02Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust
    • F01N3/021Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters
    • F01N3/033Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters in combination with other devices
    • F01N3/035Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters in combination with other devices with catalytic reactors, e.g. catalysed diesel particulate filters
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    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
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    • B01D2255/915Catalyst supported on particulate filters
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Abstract

【課題】圧力損失の増加を抑制しつつ、浄化性能を向上させることが可能なハニカムフィルタを提供する。【解決手段】流入端面11から流出端面12まで延びる流体の流路となる複数のセル2を取り囲むように配置された多孔質の隔壁1を有する柱状のハニカム構造体4と、セル2の流入端面11側の端部又は流出端面12側の端部のいずれか一方に配設された多孔質の目封止部5と、を備え、隔壁1の厚さが152~254μmであり、ハニカム構造体4のセル密度が38.8~62.0個/cm2であり、水銀圧入法によって測定された隔壁1の細孔径分布において、累積細孔容積が全細孔容積の50%となる細孔径D50が11~15μmであり、水銀圧入法によって測定された隔壁1の気孔率が60~75%であり、多孔質の隔壁1内に形成された気孔の濡れ面積Aを、当該気孔の断面積Sで除した値である隔壁濡れ面積比(A/S)が0.21~0.35m2/m2である。【選択図】図3A honeycomb filter capable of improving purification performance while suppressing an increase in pressure loss is provided. [Solution] The honeycomb structure 4 is provided with a columnar honeycomb structure having porous partition walls 1 arranged to surround a plurality of cells 2 which form a fluid flow path extending from an inflow end face 11 to an outflow end face 12, and porous plugging portions 5 arranged at either the end of the cells 2 on the inflow end face 11 side or the end on the outflow end face 12 side, wherein the partition walls 1 have a thickness of 152 to 254 μm, the honeycomb structure 4 has a cell density of 38.8 to 62.0 cells/cm2, the pore size distribution of the partition walls 1 measured by mercury intrusion porosimetry has a pore size D50 at which the cumulative pore volume is 50% of the total pore volume of 11 to 15 μm, the porosity of the partition walls 1 measured by mercury intrusion porosimetry is 60 to 75%, and the partition wall wetted area ratio (A/S), which is the value obtained by dividing the wetted area A of pores formed in the porous partition walls 1 by the cross-sectional area S of the pores, is 0.21 to 0.35 m2/m2. [Selected figure] Figure 3

Description

本発明は、ハニカムフィルタに関する。更に詳しくは、圧力損失の増加を抑制しつつ、浄化性能を向上させることが可能なハニカムフィルタに関する。 The present invention relates to a honeycomb filter. More specifically, the present invention relates to a honeycomb filter that can improve purification performance while suppressing an increase in pressure loss.

内燃機関から排出される排ガスに含まれる粒子状物質の排出量を低減するための手段としては、内燃機関の排ガス通路に粒子状物質を堆積させ捕集することを目的としたパティキュレートフィルタを設ける方法が知られている(例えば、特許文献1)。特に、近年では、搭載スペースの省スペース化等の観点から、粒子状物質の排出抑制と、一酸化炭素(CO)、炭化水素(HC)及び窒素酸化物(NOx)等の有害成分の除去を同時に行うために、パティキュレートフィルタに触媒スラリーを塗工し、これを焼成することで触媒層を設けることが検討されている。 As a means for reducing the amount of particulate matter contained in exhaust gas discharged from an internal combustion engine, a method of providing a particulate filter for the purpose of depositing and collecting particulate matter in the exhaust gas passage of the internal combustion engine is known (for example, Patent Document 1). In particular, in recent years, from the viewpoint of saving mounting space, etc., studies have been conducted on providing a catalyst layer by applying a catalyst slurry to the particulate filter and baking it in order to simultaneously suppress the emission of particulate matter and remove harmful components such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx).

排ガス浄化用のパティキュレートフィルタとして、例えば、ハニカム構造体を用いたハニカムフィルタが知られている。ハニカム構造体は、コージェライトなどの多孔質セラミックスによって構成された隔壁を有し、この隔壁によって複数のセルが区画形成されたものである。ハニカムフィルタは、上述したハニカム構造体に対して、複数のセルの流入端面側の開口部と流出端面側の開口部とを交互に目封止するように目封止部を配設したものである。 As a particulate filter for purifying exhaust gas, for example, a honeycomb filter using a honeycomb structure is known. The honeycomb structure has partition walls made of porous ceramics such as cordierite, and multiple cells are partitioned by these partition walls. A honeycomb filter is a honeycomb structure in which plugging portions are arranged so that the openings on the inflow end face side and the openings on the outflow end face side of multiple cells are alternately plugged.

特開2002-219319号公報JP 2002-219319 A

触媒層を設けたハニカムフィルタにおいては、触媒による排ガスの浄化性能を高めるためには、触媒が担持される多孔質の隔壁(別言すれば、多孔質担体)の表面積を増大させ、触媒と排ガスの接触頻度を増加させることが有用である。例えば、隔壁を構成する多孔質担体の表面積を増大させ方法として、ハニカム構造体のセル密度を大きくすること等が考えられるが、セル密度の増大は、大幅な圧力損失の増加を招いてしまうという問題があった。特に、ガソリンパティキュレートフィルタ(GPF)に代表されるハニカムフィルタにおいて、圧力損失の増加を抑制しつつ、浄化性能を向上させることが可能なハニカムフィルタの開発が要望されている。 In honeycomb filters with a catalyst layer, in order to improve the exhaust gas purification performance of the catalyst, it is useful to increase the surface area of the porous partition walls (in other words, the porous carrier) on which the catalyst is supported, and to increase the frequency of contact between the catalyst and the exhaust gas. For example, one method of increasing the surface area of the porous carrier that constitutes the partition walls is to increase the cell density of the honeycomb structure, but there is a problem in that an increase in cell density leads to a significant increase in pressure loss. In particular, there is a demand for the development of honeycomb filters that can improve purification performance while suppressing an increase in pressure loss, particularly in honeycomb filters such as gasoline particulate filters (GPFs).

本発明は、このような従来技術の有する問題点に鑑みてなされたものである。本発明によれば、圧力損失の増加を抑制しつつ、浄化性能を向上させることが可能なハニカムフィルタが提供される。 The present invention was made in consideration of the problems associated with the conventional technology. The present invention provides a honeycomb filter that can improve purification performance while suppressing an increase in pressure loss.

本発明によれば、以下に示す、ハニカムフィルタが提供される。 According to the present invention, the following honeycomb filter is provided.

[1] 流入端面から流出端面まで延びる流体の流路となる複数のセルを取り囲むように配置された多孔質の隔壁を有する柱状のハニカム構造体と、
前記セルの前記流入端面側の端部又は前記流出端面側の端部のいずれか一方に配設された目封止部と、を備え、
前記隔壁の厚さが、152~254μmであり、
前記ハニカム構造体のセル密度が、38.8~62.0個/cmであり、
水銀圧入法によって測定された前記隔壁の細孔径分布において、累積細孔容積が全細孔容積の50%となる細孔径D50が、11~15μmであり、
水銀圧入法によって測定された前記隔壁の気孔率が、60~75%であり、
多孔質の前記隔壁内に形成された気孔の濡れ面積Aを、当該気孔の断面積Sで除した値である隔壁濡れ面積比(A/S)が、0.21~0.35m/mである、ハニカムフィルタ。
[1] A columnar honeycomb structure having porous partition walls arranged to surround a plurality of cells that serve as fluid flow paths extending from an inflow end face to an outflow end face;
A plugging portion is provided at either one of the end portion on the inlet end surface side or the end portion on the outlet end surface side of the cell,
The thickness of the partition wall is 152 to 254 μm,
The honeycomb structure has a cell density of 38.8 to 62.0 cells/ cm2 ;
In a pore size distribution of the partition walls measured by mercury intrusion porosimetry, a pore size D50 at which a cumulative pore volume becomes 50% of a total pore volume is 11 to 15 μm,
the porosity of the partition walls measured by mercury porosimetry is 60 to 75%,
A honeycomb filter, wherein a partition wall wet area ratio (A/S), which is a value obtained by dividing a wet area A of a pore formed in the porous partition wall by a cross-sectional area S of the pore, is 0.21 to 0.35 m 2 /m 2 .

[2] 水銀圧入法によって測定された前記隔壁の前記細孔径分布において、累積細孔容積が全細孔容積の10%となる細孔径D10が、5.5~7.5μmである、前記[1]に記載のハニカムフィルタ。 [2] The honeycomb filter according to [1], wherein the pore diameter D10 at which the cumulative pore volume is 10% of the total pore volume in the pore diameter distribution of the partition walls measured by mercury intrusion porosimetry is 5.5 to 7.5 μm.

[3] 水銀圧入法によって測定された前記隔壁の前記細孔径分布において、累積細孔容積が全細孔容積の90%となる細孔径D90が、35.0μm以下である、前記[1]又は[2]に記載のハニカムフィルタ。 [3] The honeycomb filter according to [1] or [2], wherein the pore diameter D90, at which the cumulative pore volume is 90% of the total pore volume, in the pore diameter distribution of the partition walls measured by mercury intrusion porosimetry, is 35.0 μm or less.

本発明のハニカムフィルタは、圧力損失の増加を抑制しつつ、浄化性能を向上させることができる。例えば、ハニカムフィルタに触媒スラリーを塗工し、これを焼成することで触媒層を設ける場合、触媒スラリーは、ハニカム構造体を構成する多孔質の隔壁内へと浸透する形で塗布される。本発明のハニカムフィルタは、隔壁濡れ面積比(A/S)を0.21~0.35m/mとすることで、隔壁に形成された気孔のうち、相対的に小径の気孔を増加させ、隔壁内の触媒が塗布される表面積を増大させることができる。このため、このようなハニカムフィルタに触媒層を設けた際に、排ガスと触媒との接触頻度が増加し、ハニカムフィルタによる浄化性能を向上させることができる。また、本発明のハニカムフィルタにおいて、ハニカム構造体のセル密度を38.8~62.0個/cmの範囲としており、セル密度の過度の増加を行うことなく、上述したような浄化性能の向上を実現することができる。このため、本発明のハニカムフィルタは、セル密度を増加させることで浄化性能の向上を図るといった従来手法に比して、圧力損失の増加を有効に抑制しつつ、より効果的に浄化性能を向上させることができる。 The honeycomb filter of the present invention can improve the purification performance while suppressing an increase in pressure loss. For example, when a catalyst layer is provided by coating a honeycomb filter with a catalyst slurry and firing the coated catalyst slurry, the catalyst slurry is applied in a manner that the catalyst slurry penetrates into the porous partition walls constituting the honeycomb structure. In the honeycomb filter of the present invention, the partition wall wet area ratio (A/S) is set to 0.21 to 0.35 m 2 /m 2 , and thus it is possible to increase the number of relatively small pores among the pores formed in the partition walls, and to increase the surface area in the partition walls to which the catalyst is applied. Therefore, when a catalyst layer is provided on such a honeycomb filter, the frequency of contact between the exhaust gas and the catalyst increases, and the purification performance of the honeycomb filter can be improved. In addition, in the honeycomb filter of the present invention, the cell density of the honeycomb structure is set to a range of 38.8 to 62.0 cells/cm 2 , and the above-mentioned improvement in purification performance can be realized without excessively increasing the cell density. Therefore, the honeycomb filter of the present invention can more effectively improve purification performance while effectively suppressing an increase in pressure loss, compared to conventional methods of improving purification performance by increasing cell density.

本発明のハニカムフィルタの一の実施形態を模式的に示す斜視図である。1 is a perspective view showing a schematic view of one embodiment of a honeycomb filter of the present invention. 図1に示すハニカムフィルタの流入端面側を示す平面図である。FIG. 2 is a plan view showing an inlet end face side of the honeycomb filter shown in FIG. 1 . 図2のA-A’断面を模式的に示す断面図である。3 is a cross-sectional view showing a schematic cross section taken along the line A-A' in FIG. 2. 隔壁濡れ面積比(A/S)を求めるためのボクセルデータの概念図である。FIG. 13 is a conceptual diagram of voxel data for determining a partition wall wetted area ratio (A/S).

以下、本発明の実施の形態について説明するが、本発明は以下の実施の形態に限定されるものではない。したがって、本発明の趣旨を逸脱しない範囲で、当業者の通常の知識に基づいて、以下の実施の形態に対し適宜変更、改良等が加えられたものも本発明の範囲に入ることが理解されるべきである。 The following describes the embodiments of the present invention, but the present invention is not limited to the following embodiments. Therefore, it should be understood that modifications and improvements to the following embodiments, based on the ordinary knowledge of a person skilled in the art, fall within the scope of the present invention, as long as they do not deviate from the spirit of the present invention.

(1)ハニカムフィルタ:
本発明のハニカムフィルタの一の実施形態は、図1~図3に示すようなハニカムフィルタ100である。ここで、図1は、本発明のハニカムフィルタの一の実施形態を模式的に示す斜視図である。図2は、図1に示すハニカムフィルタの流入端面側を示す平面図である。図3は、図2のA-A’断面を模式的に示す断面図である。
(1) Honeycomb filter:
One embodiment of the honeycomb filter of the present invention is a honeycomb filter 100 as shown in Figures 1 to 3. Here, Figure 1 is a perspective view that shows one embodiment of the honeycomb filter of the present invention. Figure 2 is a plan view showing the inflow end face side of the honeycomb filter shown in Figure 1. Figure 3 is a cross-sectional view that shows a cross section taken along line AA' in Figure 2.

図1~図3に示すように、ハニカムフィルタ100は、ハニカム構造体4と、目封止部5と、を備えている。ハニカム構造体4は、流入端面11から流出端面12まで延びる流体の流路となる複数のセル2を取り囲むように配置された多孔質の隔壁1を有する柱状のものである。ハニカムフィルタ100において、ハニカム構造体4は、柱状を呈し、その外周側面に、外周壁3を更に有している。即ち、外周壁3は、格子状に配設された隔壁1を囲繞するように配設されている。 As shown in Figures 1 to 3, the honeycomb filter 100 comprises a honeycomb structure 4 and plugging portions 5. The honeycomb structure 4 is columnar with porous partition walls 1 arranged to surround a plurality of cells 2 that serve as fluid flow paths extending from the inlet end face 11 to the outlet end face 12. In the honeycomb filter 100, the honeycomb structure 4 is columnar and further has an outer peripheral wall 3 on its outer peripheral side. In other words, the outer peripheral wall 3 is arranged to surround the partition walls 1 arranged in a lattice pattern.

目封止部5は、それぞれのセル2の流入端面11側又は流出端面12側の開口部に配設されている。図1~図3に示すハニカムフィルタ100においては、所定のセル2の流入端面11側の端部の開口部、及び残余のセル2の流出端面12側の端部の開口部に、目封止部5がそれぞれ配設されている。流出端面12側の開口部に目封止部5が配設され、流入端面11側が開口したセル2を、流入セル2aとする。また、流入端面11側の開口部に目封止部5が配設され、流出端面12側が開口したセル2を、流出セル2bとする。流入セル2aと流出セル2bとは、隔壁1を隔てて交互に配設されていることが好ましい。そして、それによって、ハニカムフィルタ100の両端面に、目封止部5と「セル2の開口部」とにより、市松模様が形成されていることが好ましい。 The plugging portion 5 is disposed at the opening on the inlet end face 11 side or the outlet end face 12 side of each cell 2. In the honeycomb filter 100 shown in Figures 1 to 3, the plugging portion 5 is disposed at the opening on the inlet end face 11 side of a certain cell 2 and at the opening on the outlet end face 12 side of the remaining cells 2. The cell 2 in which the plugging portion 5 is disposed at the opening on the outlet end face 12 side and the inlet end face 11 side is opened is called the inlet cell 2a. The cell 2 in which the plugging portion 5 is disposed at the opening on the inlet end face 11 side and the outlet end face 12 side is opened is called the outlet cell 2b. The inlet cell 2a and the outlet cell 2b are preferably disposed alternately with the partition wall 1 between them. As a result, it is preferable that a checkered pattern is formed on both end faces of the honeycomb filter 100 by the plugging portion 5 and the "opening of the cell 2".

ハニカムフィルタ100は、ハニカム構造体4及び当該ハニカム構造体4を構成する隔壁1の構成について、特に主要な特性を有している。即ち、ハニカム構造体4を構成する隔壁1は、当該隔壁1の厚さが、152~254μmである。また、ハニカム構造体4のセル密度が、38.8~62.0個/cmである。また、水銀圧入法によって測定された隔壁1の細孔径分布において、累積細孔容積が全細孔容積の50%となる細孔径D50が、11~15μmであり、水銀圧入法によって測定された隔壁1の気孔率が、60~75%である。更に、多孔質の隔壁1内に形成された気孔の濡れ面積Aを、当該気孔の断面積Sで除した値である隔壁濡れ面積比(A/S)が、0.21~0.35m/mである。以下、多孔質の隔壁1に形成された微細な空孔のことを、隔壁1の「気孔」又は「細孔」ということがある。 The honeycomb filter 100 has particularly major characteristics with respect to the configuration of the honeycomb structure 4 and the partition walls 1 constituting the honeycomb structure 4. That is, the partition walls 1 constituting the honeycomb structure 4 have a thickness of 152 to 254 μm. The honeycomb structure 4 has a cell density of 38.8 to 62.0 cells/cm 2. In addition, in the pore size distribution of the partition walls 1 measured by mercury intrusion porosimetry, the pore size D50 at which the cumulative pore volume is 50% of the total pore volume is 11 to 15 μm, and the porosity of the partition walls 1 measured by mercury intrusion porosimetry is 60 to 75%. Furthermore, the partition wall wet area ratio (A/S), which is the value obtained by dividing the wet area A of the pores formed in the porous partition walls 1 by the cross-sectional area S of the pores, is 0.21 to 0.35 m 2 /m 2 . Hereinafter, the minute holes formed in the porous partition wall 1 may be referred to as the “pores” or “fine holes” of the partition wall 1 .

このように構成されたハニカムフィルタ100は、圧力損失の増加を抑制しつつ、浄化性能を向上させることができる。例えば、ハニカムフィルタ100に触媒スラリーを塗工し、これを焼成することで触媒層を設ける場合、触媒スラリーは、ハニカム構造体4を構成する多孔質の隔壁1内へと浸透する形で塗布される。ハニカムフィルタ100は、隔壁濡れ面積比(A/S)を0.21~0.35m/mとすることで、隔壁1の気孔のうち、相対的に小径の気孔を増加させ、触媒が塗布される表面積を増大させることができる。このため、ハニカムフィルタ100に触媒層を設けた際に、排ガスと触媒との接触頻度が増加し、ハニカムフィルタ100による浄化性能を向上させることができる。また、ハニカムフィルタ100において、ハニカム構造体4のセル密度を38.8~62.0個/cmの範囲としており、セル密度の過度の増加を行うことなく、浄化性能の向上を実現することができる。このため、ハニカムフィルタ100は、セル密度を増加させることで浄化性能の向上を図るといった従来手法に比して、圧力損失の増加を有効に抑制しつつ、より効果的に浄化性能を向上させることができる。以下、本実施形態のハニカムフィルタ100について、更に詳細に説明する。 The honeycomb filter 100 thus configured can improve the purification performance while suppressing an increase in pressure loss. For example, when a catalyst layer is provided by coating the honeycomb filter 100 with a catalyst slurry and firing the coated catalyst slurry, the catalyst slurry is applied in a manner that it penetrates into the porous partition walls 1 constituting the honeycomb structure 4. The honeycomb filter 100 can increase the number of relatively small pores among the pores of the partition walls 1 and increase the surface area to which the catalyst is applied by setting the partition wall wet area ratio (A/S) to 0.21 to 0.35 m 2 /m 2. Therefore, when a catalyst layer is provided on the honeycomb filter 100, the frequency of contact between the exhaust gas and the catalyst increases, and the purification performance of the honeycomb filter 100 can be improved. In the honeycomb filter 100, the cell density of the honeycomb structure 4 is set to a range of 38.8 to 62.0 cells/cm 2 , and the purification performance can be improved without excessively increasing the cell density. Therefore, the honeycomb filter 100 can effectively improve the purification performance while effectively suppressing an increase in pressure loss, compared to the conventional method of improving the purification performance by increasing the cell density. Hereinafter, the honeycomb filter 100 of the present embodiment will be described in further detail.

ハニカム構造体4を構成する隔壁1は、当該隔壁1の厚さが、152~254μmである。隔壁1の厚さを上記数値範囲とすることで、構造体としての強度の確保と圧力損失増加抑制の両立が達成できる。例えば、隔壁1の厚さが152μm未満であると、強度低下の点で好ましくない。隔壁1の厚さが254μmを超えると、圧力損失が大きく増大するため好ましくない。特に限定されることはないが、隔壁1の厚さは、203~254μmであることが好ましく、203~229μmであることが更に好ましい。隔壁1の厚さは、例えば、走査型電子顕微鏡又はマイクロスコープ(microscope)を用いて測定することができる。 The partition walls 1 constituting the honeycomb structure 4 have a thickness of 152 to 254 μm. By setting the thickness of the partition walls 1 within the above numerical range, it is possible to achieve both ensuring the strength of the structure and suppressing an increase in pressure loss. For example, if the thickness of the partition walls 1 is less than 152 μm, this is not preferable in terms of a decrease in strength. If the thickness of the partition walls 1 exceeds 254 μm, this is not preferable because the pressure loss increases significantly. Although not particularly limited, the thickness of the partition walls 1 is preferably 203 to 254 μm, and more preferably 203 to 229 μm. The thickness of the partition walls 1 can be measured, for example, using a scanning electron microscope or a microscope.

また、上記したような隔壁1を有するハニカム構造体4は、当該ハニカム構造体4のセル密度が、38.8~62.0個/cmである。セル密度を上記数値範囲とすることで、灰(以下、「アッシュ」又は「Ash」ともいう)堆積時の圧力損失の増加を抑制できる。例えば、セル密度が38.8個/cm未満であると、幾何学的表面積(GSA)がさがりAsh堆積層の厚みが増し、圧力損失が大きく増加するため好ましくない。セル密度が62.0個/cmを超えると、ガス入口端面の水力直径が小さくなり、圧力損失が急激に増加するため好ましくない。特に限定されることはないが、ハニカム構造体4のセル密度は、43~54個/cmであることが好ましく、45~48個/cmであることが更に好ましい。 In addition, the honeycomb structure 4 having the partition walls 1 as described above has a cell density of 38.8 to 62.0 cells/cm 2. By setting the cell density within the above numerical range, the increase in pressure loss during ash (hereinafter also referred to as "ash" or "Ash") deposition can be suppressed. For example, if the cell density is less than 38.8 cells/cm 2 , the geometric surface area (GSA) decreases, the thickness of the Ash deposition layer increases, and the pressure loss increases significantly, which is not preferable. If the cell density exceeds 62.0 cells/cm 2 , the hydraulic diameter of the gas inlet end face decreases, and the pressure loss increases rapidly, which is not preferable. Although not particularly limited, the cell density of the honeycomb structure 4 is preferably 43 to 54 cells/cm 2 , and more preferably 45 to 48 cells/cm 2 .

隔壁1は、水銀圧入法によって測定された隔壁1の細孔径分布において、累積細孔容積が全細孔容積の50%となる細孔径D50が、11~15μmである。以下、隔壁1の細孔径分布において、累積細孔容積が全細孔容積の50%となる細孔径D50のことを、単に、隔壁1の細孔径分布における「D50」ということがある。この「D50」は、隔壁1の細孔径分布における全細孔容積の半分の容積を与える細孔径と定義して算出した値であり、隔壁1の平均細孔径とも称されることがある。D50が11μm未満であると、触媒塗布後の圧力損失が激的に増大する可能性があるため好ましくない。細孔径D50が15μmを超えると、捕集性能が低下する点で好ましくない。特に限定されることはないが、D50は、12~15μmであることが好ましく、13~15μmであることが更に好ましい。 In the pore size distribution of the partition wall 1 measured by mercury intrusion porosimetry, the pore size D50 at which the cumulative pore volume is 50% of the total pore volume is 11 to 15 μm. Hereinafter, the pore size D50 at which the cumulative pore volume is 50% of the total pore volume in the pore size distribution of the partition wall 1 may be simply referred to as "D50" in the pore size distribution of the partition wall 1. This "D50" is a value calculated by defining it as the pore size that gives half the total pore volume in the pore size distribution of the partition wall 1, and may also be referred to as the average pore size of the partition wall 1. If D50 is less than 11 μm, it is not preferable because the pressure loss after catalyst application may increase dramatically. If the pore size D50 exceeds 15 μm, it is not preferable because the collection performance decreases. Although not particularly limited, D50 is preferably 12 to 15 μm, and more preferably 13 to 15 μm.

隔壁1の累積細孔容積は、水銀圧入法によって測定された値である。隔壁1の累積細孔容積の測定は、例えば、Micromeritics社製のオートポア9500(商品名)を用いて行うことができる。隔壁1の累積細孔容積の測定は、以下のような方法によって行うことができる。まず、ハニカムフィルタ100から隔壁1の一部を切り出して、累積細孔容積測定用の試験片を作製する。試験片の大きさについては特に制限はないが、例えば、縦、横、高さのそれぞれの長さが、約10mm、約10mm、約20mmの直方体であることが好ましい。試験片を切り出す隔壁1の部位については特に制限はないが、試験片は、ハニカム構造部の軸方向の中心付近から切り出して作製することが好ましい。得られた試験片を、測定装置の測定用セル内に収納し、この測定用セル内を減圧する。次に、測定用セル内に水銀を導入する。次に、測定用セル内に導入した水銀を加圧し、加圧時において、試験片内に存在する細孔中に押し込まれた水銀の体積を測定する。この際、水銀に加える圧力を増やすにしたがって、細孔径の大きな細孔から、順次、細孔径の小さな細孔に水銀が押し込まれることとなる。したがって、「水銀に加える圧力」と「細孔中に押し込まれた水銀の体積」との関係から、「試験片に形成された細孔の細孔径」と「累積細孔容積」の関係を求めることができる。更に詳細に説明と、上記したように水銀圧入法により、真空状態に密閉した容器内にある試料(試験片)の細孔に水銀を浸入させるために徐々に圧力を加えていくと、圧力が加えられた水銀は、試料の大きな細孔から小さな細孔へと順に浸入していく。その時の圧力と圧入された水銀量から、試料に形成された細孔の細孔径、及びその細孔容積を算出することができる。以下、細孔径をD1、D2、D3・・・とした場合、D1>D2>D3・・・の関係を満たすものとする。ここで、各測定ポイント間(例えば、D1からD2)の平均細孔径Dは、「平均細孔径D=(D1+D2)/2」として横軸に示すことができる。また、縦軸のLog微分細孔容積は、各測定ポイント間の細孔容積の増加分dVを細孔径の対数扱いの差分値(即ち、「log(D1)-log(D2)」)で割った値とすることができる。 The cumulative pore volume of the partition wall 1 is a value measured by mercury intrusion porosimetry. The cumulative pore volume of the partition wall 1 can be measured, for example, using Autopore 9500 (product name) manufactured by Micromeritics. The cumulative pore volume of the partition wall 1 can be measured by the following method. First, a part of the partition wall 1 is cut out from the honeycomb filter 100 to prepare a test piece for measuring the cumulative pore volume. There is no particular restriction on the size of the test piece, but it is preferable that the length, width, and height are, for example, a rectangular parallelepiped with lengths of about 10 mm, about 10 mm, and about 20 mm. There is no particular restriction on the part of the partition wall 1 from which the test piece is cut out, but it is preferable to cut the test piece from near the center of the axial direction of the honeycomb structure. The obtained test piece is placed in a measurement cell of a measurement device, and the pressure in the measurement cell is reduced. Next, mercury is introduced into the measurement cell. Next, the mercury introduced into the measurement cell is pressurized, and the volume of mercury forced into the pores present in the test piece is measured at the time of pressurization. At this time, as the pressure applied to the mercury is increased, the mercury is forced from the pores with the larger pore diameter to the pores with the smaller pore diameter. Therefore, the relationship between the "pore diameter of the pores formed in the test piece" and the "cumulative pore volume" can be obtained from the relationship between the "pressure applied to the mercury" and the "volume of mercury forced into the pores". In further detail, as described above, when pressure is gradually applied to infiltrate mercury into the pores of the sample (test piece) in a container sealed in a vacuum state by the mercury intrusion method, the mercury to which pressure is applied infiltrates the pores of the sample from the larger pores to the smaller pores. From the pressure at that time and the amount of mercury pressed in, the pore diameter of the pores formed in the sample and its pore volume can be calculated. Hereinafter, when the pore diameters are D1, D2, D3, etc., it is assumed that the relationship D1>D2>D3... is satisfied. Here, the average pore diameter D between each measurement point (e.g., from D1 to D2) can be shown on the horizontal axis as "average pore diameter D = (D1 + D2) / 2". Also, the log differential pore volume on the vertical axis can be the value obtained by dividing the increase dV in the pore volume between each measurement point by the logarithmic difference value of the pore diameter (i.e., "log (D1) - log (D2)").

水銀圧入法によって測定された隔壁1の気孔率が、60~75%である。隔壁1の気孔率が60%未満であると、触媒塗布時の圧力損失が激的に増大する可能性があるため好ましくない。隔壁1の気孔率が75%を超えると、強度低下の点で好ましくない。特に限定されることはないが、隔壁1の気孔率は、61~70%であることが好ましく、62~66%であることが更に好ましい。隔壁1の気孔率は、例えば、Micromeritics社製のオートポア9500(商品名)を用いて測定することができる。気孔率の測定は、ハニカムフィルタ100から隔壁1の一部を切り出して試験片とし、このようにして得られた試験片を用いて行うことができる。 The porosity of the partition wall 1 measured by mercury intrusion is 60 to 75%. If the porosity of the partition wall 1 is less than 60%, it is not preferable because the pressure loss during catalyst application may increase dramatically. If the porosity of the partition wall 1 exceeds 75%, it is not preferable because the strength decreases. Although not particularly limited, the porosity of the partition wall 1 is preferably 61 to 70%, and more preferably 62 to 66%. The porosity of the partition wall 1 can be measured, for example, using Autopore 9500 (product name) manufactured by Micromeritics. The porosity can be measured by cutting a part of the partition wall 1 from the honeycomb filter 100 as a test piece and using the test piece thus obtained.

更に、ハニカムフィルタ100は、以下に説明する隔壁濡れ面積比(A/S)が、0.21~0.35m/mである。隔壁濡れ面積比(A/S)とは、多孔質の隔壁1内に形成された気孔の濡れ面積A(m)を、当該気孔の断面積S(m)で除した値(A/S)である。気孔の濡れ面積A(m)及び断面積S(m)は、隔壁1に対してCTスキャンを行うことによって得た3次元のボクセルデータ60を用いて算出する。図4は、ボクセルデータ60の概念図である。まず、隔壁1(例えば、図3参照)の厚さ方向をX方向とし、セル2の軸方向(例えば、図3の上下方向)をY方向として、XY平面を撮影断面とする。次に、撮影断面をXY方向に垂直なZ方向にずらして複数撮影するように隔壁1のCTスキャンを行って複数の画像データを取得し、この画像データに基づいて図4の上段のようなボクセルデータ60を得る。X,Y,Zの各方向の解像度はそれぞれ1.2μmとし、これにより得られる1辺が1.2μmの立方体が3次元のボクセルデータ60の最小単位すなわちボクセルとなる。なお、CTスキャンで得られる撮影断面の画像データはZ方向の厚みのない平面のデータであるが、各撮影断面は撮影断面のZ方向の間隔分(1.2μm)の厚みがあるものとして扱う。すなわち画像データの二次元の各画素を1辺が1.2μmの立方体(ボクセル)として扱う。ボクセルデータ60の大きさは、図3の上段に示すように、X方向が300μm(=1.2μm×250ボクセル),Y方向が480μm(=1.2μm×400ボクセル),Z方向が480μm(=1.2μm×400ボクセル)の直方体とする。各ボクセルはX,Y,Z座標(座標の値1がボクセルの一辺の長さである1.2μmに対応する)により位置が表されるとともに、空間(気孔)を表す空間ボクセルであるか物体を表す物体ボクセルであるかが区別されている。空間ボクセルと物体ボクセルとの区別は、モード法を用いた2値化処理によって以下のように行う。CTスキャンによって実際に得られる複数の画像データは、X,Y,Z座標毎の輝度データである。この輝度データに基づき、全ての座標(複数の画像データの全画素)について輝度のヒストグラムを作成する。そして、ヒストグラムに現れる2つの山の間(谷)の部分の輝度値を閾値に設定し、各座標について輝度が閾値より大きいか小さいかで各座標の輝度を2値化する。これにより、各座標のボクセルが空間ボクセルであるか物体ボクセルであるかを区別する。図4の中段に、空間ボクセルと物体ボクセルとを区別した状態の一例を2次元的に示した。図4の下段には、その一部の拡大図64を2次元的に示した。なお、このようなCTスキャンは、例えば、島津製作所社製のSMX-160CT-SV3(商品名)を用いて行うことができる。CTスキャンを行う隔壁1の位置については特に制限はないが、ハニカム構造体4のセル2の延びる方向(上述したセル2の軸方向)の中央部分であることが好ましい。 Furthermore, the honeycomb filter 100 has a partition wall wet area ratio (A/S) described below of 0.21 to 0.35 m 2 /m 2. The partition wall wet area ratio (A/S) is a value (A/S) obtained by dividing the wet area A (m 2 ) of a pore formed in a porous partition wall 1 by the cross-sectional area S (m 2 ) of the pore. The wet area A (m 2 ) and cross-sectional area S (m 2 ) of the pore are calculated using three-dimensional voxel data 60 obtained by performing a CT scan on the partition wall 1. FIG. 4 is a conceptual diagram of the voxel data 60. First, the thickness direction of the partition wall 1 (for example, see FIG. 3) is the X direction, the axial direction of the cell 2 (for example, the vertical direction in FIG. 3) is the Y direction, and the XY plane is the photographed cross section. Next, a CT scan of the partition wall 1 is performed so that the photographed cross section is photographed multiple times while being shifted in the Z direction perpendicular to the XY direction, and multiple image data are obtained, and voxel data 60 as shown in the upper part of Fig. 4 is obtained based on this image data. The resolution in each of the X, Y, and Z directions is 1.2 µm, and a cube with a side length of 1.2 µm obtained thereby becomes the smallest unit of the three-dimensional voxel data 60, i.e., a voxel. Note that although the image data of the photographed cross section obtained by the CT scan is planar data with no thickness in the Z direction, each photographed cross section is treated as having a thickness of the interval (1.2 µm) between the photographed cross sections in the Z direction. In other words, each two-dimensional pixel of the image data is treated as a cube (voxel) with a side length of 1.2 µm. The size of the voxel data 60 is a rectangular parallelepiped with an X direction of 300 μm (=1.2 μm×250 voxels), a Y direction of 480 μm (=1.2 μm×400 voxels), and a Z direction of 480 μm (=1.2 μm×400 voxels) as shown in the upper part of FIG. 3. The position of each voxel is expressed by X, Y, and Z coordinates (where the coordinate value 1 corresponds to 1.2 μm, which is the length of one side of the voxel), and each voxel is classified as a space voxel representing a space (pore) or an object voxel representing an object. The space voxel and the object voxel are classified as follows by a binarization process using the mode method. The multiple image data actually obtained by the CT scan are brightness data for each X, Y, and Z coordinate. Based on this brightness data, a brightness histogram is created for all coordinates (all pixels of the multiple image data). Then, the brightness value of the portion between two peaks (valleys) appearing in the histogram is set as a threshold value, and the brightness of each coordinate is binarized according to whether the brightness of each coordinate is greater than or smaller than the threshold value. In this way, it is possible to distinguish whether the voxel at each coordinate is a space voxel or an object voxel. In the middle part of FIG. 4, an example of a state in which the space voxel and the object voxel are distinguished is shown two-dimensionally. In the lower part of FIG. 4, an enlarged view 64 of a part of the state is shown two-dimensionally. Note that such a CT scan can be performed using, for example, SMX-160CT-SV3 (product name) manufactured by Shimadzu Corporation. There is no particular restriction on the position of the partition wall 1 where the CT scan is performed, but it is preferable that the position is the center part in the direction in which the cell 2 of the honeycomb structure 4 extends (the axial direction of the cell 2 described above).

次に、このボクセルデータ60を用いて、気孔の断面積S’及び気孔の濡れ面積A’を算出する。気孔の断面積S’は、図4の中段及び下段に示される「空間ボクセル」が存在する範囲の面積である。このため、気孔の断面積S’は、断面積S’=空間ボクセル数×1.2μm×1.2μmとして算出することができる。濡れ面積A’は、ボクセルデータ60における空間ボクセルと物体ボクセルとの境界面の面積の合計として算出する。より具体的には、濡れ面積A’=(ボクセルデータ60中の境界面の数)×(1つの境界面の面積)として導出する。1つの境界面の面積は1.44μm(=1.2μm×1.2μm)である。例えば、図4の下段に示す拡大図64には、空間ボクセルと物体ボクセルとの境界面が6面存在するため、拡大図64における境界面の面積の合計は、6×1.44=8.64μmとなる。このようにして、濡れ面積A’を算出する。なお、これまでの説明では、気孔の断面積S’及び気孔の濡れ面積A’の単位を「μm」とした場合の例を説明しているが、適宜、ボクセルデータ60の大きさ(長さ)等の単位を「m」にて換算することで、気孔の濡れ面積A(m)及び気孔の断面積S(m)を求めることができる。そして、気孔の断面積Sと濡れ面積Aとにより隔壁濡れ面積比(A/S)を算出する。 Next, the cross-sectional area S' of the pore and the wet area A' of the pore are calculated using this voxel data 60. The cross-sectional area S' of the pore is the area of the range in which the "space voxels" shown in the middle and lower parts of FIG. 4 exist. Therefore, the cross-sectional area S' of the pore can be calculated as the cross-sectional area S'=number of space voxels×1.2 μm×1.2 μm. The wet area A' is calculated as the sum of the areas of the boundary surfaces between the space voxels and the object voxels in the voxel data 60. More specifically, the wet area A' is derived as the number of boundary surfaces in the voxel data 60×area of one boundary surface. The area of one boundary surface is 1.44 μm 2 (=1.2 μm×1.2 μm). For example, in the enlarged view 64 shown in the lower part of Fig. 4, there are six boundary surfaces between the space voxel and the object voxel, so the total area of the boundary surfaces in the enlarged view 64 is 6 x 1.44 = 8.64 µm2 . In this manner, the wet area A' is calculated. In the above description, an example is described in which the unit of the pore cross-sectional area S' and the wet area A' of the pore is " µm2 ", but the unit of the size (length) of the voxel data 60, etc., can be appropriately converted to "m" to obtain the wet area A ( m2 ) of the pore and the cross-sectional area S ( m2 ) of the pore. Then, the partition wall wet area ratio (A/S) is calculated from the cross-sectional area S of the pore and the wet area A.

ハニカムフィルタ100において、隔壁濡れ面積比(A/S)が、0.21m/m未満であると、隔壁1内の触媒が塗布される表面積(即ち、隔壁1内の濡れ面積)が少なくなる。このため、ハニカムフィルタ100に触媒層を設けた際に、排ガスと触媒との接触頻度が増加し難く、十分な浄化性能の向上が期待できない。一方で、隔壁濡れ面積比(A/S)が、0.35m/mを超えると、触媒塗布後に圧力損失が増大してしまう可能性がある点で好ましくない。隔壁濡れ面積比(A/S)は0.21~0.35m/mであればよいが、例えば、0.23~0.30m/mであることが好ましく、0.25~0.27m/mであることが更に好ましい。 In the honeycomb filter 100, if the partition wall wet area ratio (A/S) is less than 0.21 m 2 /m 2 , the surface area in the partition wall 1 where the catalyst is applied (i.e., the wet area in the partition wall 1) becomes small. For this reason, when a catalyst layer is provided in the honeycomb filter 100, the frequency of contact between the exhaust gas and the catalyst is unlikely to increase, and sufficient improvement in purification performance cannot be expected. On the other hand, if the partition wall wet area ratio (A/S) exceeds 0.35 m 2 /m 2 , it is not preferable because there is a possibility that the pressure loss increases after the catalyst is applied. The partition wall wet area ratio (A/S) may be 0.21 to 0.35 m 2 /m 2 , but for example, it is preferable that it is 0.23 to 0.30 m 2 /m 2 , and more preferably 0.25 to 0.27 m 2 /m 2 .

また、ハニカムフィルタ100は、これまでに説明した隔壁1の細孔径分布において、累積細孔容積が全細孔容積の10%となる細孔径D10が、5.5~7.5μmであることが好ましい。以下、累積細孔容積が全細孔容積の10%となる細孔径D10のことを、単に、隔壁1の細孔径分布における「D10」ということがある。D10が、5.5~7.5μmであると、触媒塗布後の圧力損失の増加を抑制できる点で好ましい。特に限定されることはないが、D10は、6.0~7.0μmであることが更に好ましい。 In addition, in the pore size distribution of the partition walls 1 of the honeycomb filter 100 described above, the pore size D10 at which the cumulative pore volume is 10% of the total pore volume is preferably 5.5 to 7.5 μm. Hereinafter, the pore size D10 at which the cumulative pore volume is 10% of the total pore volume may be simply referred to as "D10" in the pore size distribution of the partition walls 1. If D10 is 5.5 to 7.5 μm, it is preferable in that an increase in pressure loss after catalyst application can be suppressed. Although not particularly limited, it is more preferable that D10 is 6.0 to 7.0 μm.

更に、ハニカムフィルタ100は、隔壁1の細孔径分布において、累積細孔容積が全細孔容積の90%となる細孔径D90が、35.0μm以下であることが好ましい。以下、累積細孔容積が全細孔容積の90%となる細孔径D90のことを、単に、隔壁1の細孔径分布における「D90」ということがある。D90が、35.0μm以下であると、十分な捕集性能が発現できる点で好ましい。特に限定されることはないが、D90は、27.0~35.0μmであることが更に好ましく、27.0~32.0μmであることが特に好ましい。 Furthermore, in the pore size distribution of the partition walls 1 of the honeycomb filter 100, the pore size D90 at which the cumulative pore volume is 90% of the total pore volume is preferably 35.0 μm or less. Hereinafter, the pore size D90 at which the cumulative pore volume is 90% of the total pore volume may be simply referred to as "D90" in the pore size distribution of the partition walls 1. If D90 is 35.0 μm or less, this is preferable in that sufficient collection performance can be expressed. Although not particularly limited, D90 is more preferably 27.0 to 35.0 μm, and particularly preferably 27.0 to 32.0 μm.

隔壁1によって区画されるセル2の形状については特に制限はない。例えば、セル2の延びる方向に直交する断面における、セル2の形状としては、多角形、円形、楕円形等を挙げることができる。多角形としては、三角形、四角形、五角形、六角形、八角形等を挙げることができる。なお、セル2の形状は、三角形、四角形、五角形、六角形、八角形であることが好ましい。また、セル2の形状については、全てのセル2の形状が同一形状であってもよいし、異なる形状であってもよい。例えば、図示は省略するが、四角形のセルと、八角形のセルとが混在したものであってもよい。また、セル2の大きさについては、全てのセル2の大きさが同じであってもよいし、異なっていてもよい。例えば、図示は省略するが、複数のセルのうち、一部のセルの大きさを大きくし、他のセルの大きさを相対的に小さくしてもよい。なお、本発明において、セルとは、隔壁によって取り囲まれた空間のことを意味する。 There is no particular restriction on the shape of the cells 2 partitioned by the partitions 1. For example, examples of the shape of the cells 2 in a cross section perpendicular to the direction in which the cells 2 extend include polygons, circles, and ellipses. Examples of polygons include triangles, squares, pentagons, hexagons, and octagons. The shapes of the cells 2 are preferably triangles, squares, pentagons, hexagons, and octagons. The shapes of the cells 2 may be the same for all the cells 2, or may be different. For example, although not shown in the figure, the cells may be a mixture of square cells and octagonal cells. The sizes of the cells 2 may be the same for all the cells 2, or may be different. For example, although not shown in the figure, the size of some of the cells may be large, and the size of the other cells may be relatively small. In the present invention, a cell means a space surrounded by partitions.

ハニカム構造体4の形状については特に制限はない。ハニカム構造体4の形状としては、流入端面11及び流出端面12の形状が、円形、楕円形、多角形等の柱状を挙げることができる。 There are no particular limitations on the shape of the honeycomb structure 4. Examples of the shape of the honeycomb structure 4 include a cylindrical shape, such as a circle, an ellipse, or a polygon, for the inlet end face 11 and the outlet end face 12.

ハニカム構造体4の大きさ、例えば、流入端面11から流出端面12までの長さや、ハニカム構造体4のセル2の延びる方向に直交する断面の大きさについては、特に制限はない。ハニカムフィルタ100を、排ガス浄化用のフィルタとして用いた際に、最適な浄化性能を得るように、各大きさを適宜選択すればよい。 There are no particular limitations on the size of the honeycomb structure 4, for example, the length from the inlet end face 11 to the outlet end face 12, or the size of the cross section perpendicular to the extension direction of the cells 2 of the honeycomb structure 4. When the honeycomb filter 100 is used as a filter for purifying exhaust gas, each size can be appropriately selected to obtain optimal purification performance.

ハニカム構造体4を構成する隔壁1の材料については特に制限はない。例えば、隔壁1の材料が、コージェライト、炭化珪素、珪素-炭化珪素複合材料、コージェライト-炭化珪素複合材料、窒化珪素、ムライト、アルミナ及びチタン酸アルミニウムから構成される群から選択される少なくとも1種を含むことが好ましい。本実施形態のハニカムフィルタ100においては、隔壁1の材料として、コージェライト、炭化珪素、チタン酸アルミニウムのうちの少なくとも1種を含む材料を好適例として挙げることができる。 There are no particular limitations on the material of the partition walls 1 that constitute the honeycomb structure 4. For example, it is preferable that the material of the partition walls 1 contains at least one material selected from the group consisting of cordierite, silicon carbide, silicon-silicon carbide composite material, cordierite-silicon carbide composite material, silicon nitride, mullite, alumina, and aluminum titanate. In the honeycomb filter 100 of this embodiment, a suitable example of the material of the partition walls 1 is a material containing at least one of cordierite, silicon carbide, and aluminum titanate.

目封止部5の材料についても特に制限はない。例えば、上述した隔壁1の材料と同様の材料を用いることができる。 There are no particular limitations on the material of the plugging portion 5. For example, the same material as that of the partition wall 1 described above can be used.

ハニカムフィルタ100は、複数のセル2を区画形成する隔壁1に排ガス浄化用の触媒が担持されていることが好ましい。隔壁1に触媒を担持するとは、隔壁1の表面及び隔壁1に形成された細孔の内壁に、触媒がコーティングされることをいう。このように構成することによって、排ガス中のCOやNOxやHCなどを触媒反応によって無害な物質にすることができる。また、捕集した煤等のPMの酸化を促進させることができる。 The honeycomb filter 100 preferably has a catalyst for purifying exhaust gas carried on the partition walls 1 that define the multiple cells 2. Carrying a catalyst on the partition walls 1 means that the catalyst is coated on the surfaces of the partition walls 1 and on the inner walls of the pores formed in the partition walls 1. This configuration makes it possible to convert CO, NOx, HC, and other substances in the exhaust gas into harmless substances through catalytic reactions. It also makes it possible to promote the oxidation of PM such as collected soot.

隔壁1に担持する触媒については特に制限はない。例えば、白金族元素を含有する触媒であって、アルミニウム、ジルコニウム、及びセリウムのうちの少なくとも一種の元素の酸化物を含む触媒を挙げることができる。 There are no particular limitations on the catalyst supported on the partition wall 1. For example, a catalyst containing a platinum group element and an oxide of at least one of the elements aluminum, zirconium, and cerium can be used.

(2)ハニカムフィルタの製造方法:
本発明のハニカムフィルタを製造する方法については、特に制限はなく、例えば、以下のような方法を挙げることができる。まず、ハニカム構造体を作製するための可塑性の坏土を調製する。ハニカム構造体を作製するための坏土は、原料粉末として、前述の隔壁の好適な材料の中から選ばれた材料に、適宜、バインダ等の添加剤、造孔材、及び水を添加することによって調製することができる。なお、本発明のハニカムフィルタを製造する際に、坏土を調製するための原料粉末としては、例えば、カオリン、タルク、アルミナ、水酸化アルミニウム、シリカ等を用い、これらの原料粉末を、シリカが42~56質量%、アルミナが30~45質量%、マグネシアが12~16質量%の範囲に入る化学組成となるようにして調製することができる。なお、カオリン、アルミナ、水酸化アルミニウムは平均粒径が7μm以下のものを使用することで素地内の小細孔を増加させ、隔壁濡れ面積を増大することができる。
(2) Manufacturing method of honeycomb filter:
There is no particular limitation on the method for manufacturing the honeycomb filter of the present invention, and for example, the following method can be mentioned. First, a plastic clay for manufacturing a honeycomb structure is prepared. The clay for manufacturing a honeycomb structure can be prepared by appropriately adding additives such as binders, pore formers, and water to a material selected from the above-mentioned suitable materials for the partition walls as a raw material powder. In addition, when manufacturing the honeycomb filter of the present invention, for example, kaolin, talc, alumina, aluminum hydroxide, silica, etc. are used as the raw material powder for preparing the clay, and these raw material powders can be prepared so that the chemical composition falls within the range of 42 to 56 mass% silica, 30 to 45 mass% alumina, and 12 to 16 mass% magnesia. In addition, by using kaolin, alumina, and aluminum hydroxide with an average particle size of 7 μm or less, the small pores in the base material can be increased, and the partition wall wetted area can be increased.

次に、このようにして得られた坏土を押出成形することにより、複数のセルを区画形成する隔壁、及びこの隔壁を囲繞するように配設された外周壁を有する、柱状のハニカム成形体を作製する。押出成形においては、押出成形用の口金として、坏土の押出面に、成形するハニカム成形体の反転形状となるスリットが設けられた口金を用いることができる。 Next, the puddle thus obtained is extruded to produce a columnar honeycomb molded body having partition walls that define a plurality of cells and an outer peripheral wall arranged to surround the partition walls. In the extrusion molding, a die having slits on the extrusion surface of the puddle that will form the inverted shape of the honeycomb molded body to be molded can be used as the die for extrusion molding.

得られたハニカム成形体を、例えば、マイクロ波及び熱風で乾燥し、ハニカム成形体の作製に用いた材料と同様の材料で、セルの開口部を目封止することで目封止部を作製する。目封止部を作製した後に、ハニカム成形体を更に乾燥してもよい。 The obtained honeycomb formed body is dried, for example, with microwaves and hot air, and the openings of the cells are plugged with the same material as that used to produce the honeycomb formed body to produce plugged portions. After producing the plugged portions, the honeycomb formed body may be further dried.

次に、目封止部を作製したハニカム成形体を焼成することにより、ハニカムフィルタを製造する。焼成温度及び焼成雰囲気は原料により異なり、当業者であれば、選択された材料に最適な焼成温度及び焼成雰囲気を選択することができる。 Next, the honeycomb formed body with the plugged portions is fired to produce a honeycomb filter. The firing temperature and firing atmosphere vary depending on the raw materials, and a person skilled in the art can select the firing temperature and firing atmosphere that are optimal for the selected materials.

以下、本発明を実施例によって更に具体的に説明するが、本発明はこれらの実施例によって何ら限定されるものではない。 The present invention will be explained in more detail below with reference to examples, but the present invention is not limited to these examples.

(実施例1)
コージェライト化原料100質量部に、造孔材を2質量部、分散媒を2質量部、有機バインダを7質量部、それぞれ添加し、混合、混練して坏土を調製した。コージェライト化原料としては、アルミナ、水酸化アルミニウム、カオリン、タルク、及びシリカを使用した。分散媒としては、水を使用した。有機バインダとしては、メチルセルロース(Methylcellulose)を使用した。分散剤としては、デキストリン(Dextrin)を使用した。水酸化アルミニウムは平均粒径が5μmのものを使用し、ハニカム構造体を作製するための坏土を調製した。
Example 1
2 parts by mass of a pore former, 2 parts by mass of a dispersion medium, and 7 parts by mass of an organic binder were added to 100 parts by mass of the cordierite raw material, and mixed and kneaded to prepare a clay. Alumina, aluminum hydroxide, kaolin, talc, and silica were used as the cordierite raw material. Water was used as the dispersion medium. Methylcellulose was used as the organic binder. Dextrin was used as the dispersant. Aluminum hydroxide with an average particle size of 5 μm was used to prepare a clay for producing a honeycomb structure.

次に、得られた坏土を、押出成形機を用いて成形し、ハニカム成形体を作製した。次に、得られたハニカム成形体を高周波誘電加熱乾燥した後、熱風乾燥機を用いて更に乾燥した。ハニカム成形体におけるセルの形状は、四角形とした。 Next, the obtained clay was molded using an extrusion molding machine to produce a honeycomb molded body. Next, the obtained honeycomb molded body was dried using high-frequency dielectric heating, and then further dried using a hot air dryer. The shape of the cells in the honeycomb molded body was rectangular.

次に、乾燥後のハニカム成形体に、目封止部を形成した。まず、ハニカム成形体の流入端面にマスクを施した。次に、マスクの施された端部(流入端面側の端部)を目封止スラリーに浸漬し、マスクが施されていないセル(流出セル)の開口部に目封止スラリーを充填した。このようにして、ハニカム成形体の流入端面側に、目封止部を形成した。そして、乾燥後のハニカム成形体の流出端面についても同様にして、流入セルにも目封止部を形成した。 Next, plugging sections were formed on the dried honeycomb formed body. First, a mask was applied to the inflow end face of the honeycomb formed body. Next, the masked end (the end on the inflow end face side) was immersed in plugging slurry, and the plugging slurry was filled into the openings of the unmasked cells (outflow cells). In this way, plugging sections were formed on the inflow end face side of the honeycomb formed body. Then, plugging sections were formed in the inflow cells on the outflow end face of the dried honeycomb formed body in the same manner.

次に、目封止部を形成したハニカム成形体をマイクロ波乾燥機で乾燥し、更に熱風乾燥機で完全に乾燥させた後、ハニカム成形体の両端面を切断し、所定の寸法に整えた。次に、乾燥したハニカム成形体を、脱脂し、焼成して、実施例1のハニカムフィルタを製造した。 Next, the honeycomb formed body with the plugged portions was dried in a microwave dryer and then completely dried in a hot air dryer, after which both end faces of the honeycomb formed body were cut and adjusted to the specified dimensions. Next, the dried honeycomb formed body was degreased and fired to produce the honeycomb filter of Example 1.

実施例1のハニカムフィルタは、端面の直径が132.6mmであり、セルの延びる方向の長さが127.3mmであった。また、隔壁の厚さが210.8μmであり、セル密度が46.8個/cmであった。隔壁の厚さの値を表1に示す。 The honeycomb filter of Example 1 had an end face diameter of 132.6 mm, a length in the cell extension direction of 127.3 mm, a partition wall thickness of 210.8 μm, and a cell density of 46.8 cells/cm 2. The partition wall thickness values are shown in Table 1.

実施例1のハニカムフィルタについて、以下の方法で、隔壁の「気孔率(%)」、「D50(μm)」、「D10(μm)」及び「D90(μm)」の測定を行った。また、以下の方法で、隔壁の「隔壁濡れ面積比」を求めた。各結果を、表1に示す。 For the honeycomb filter of Example 1, the "porosity (%)", "D50 (μm)", "D10 (μm)" and "D90 (μm)" of the partition walls were measured by the following method. In addition, the "partition wall wet area ratio" of the partition walls was determined by the following method. The results are shown in Table 1.

[気孔率(%)、D50(μm)、D10(μm)及びD90(μm)]
隔壁の気孔率(%)、D50(μm)、D10(μm)及びD90(μm)は、Micromeritics社製のオートポア9500(商品名)を用いて測定した。D50(μm)、D10(μm)及びD90(μm)の各値は、隔壁の細孔径分布において累積細孔容積が全細孔容積の50%、10%及び90%となる各細孔径(μm)を確認することにより求めた。これらの測定においては、ハニカムフィルタから隔壁の一部を切り出して試験片とし、得られた試験片を用いて測定を行った。試験片は、縦、横、高さのそれぞれの長さが、約10mm、約10mm、約20mmの直方体のものとした。試験片の採取箇所については、ハニカム構造体の軸方向の中心付近とした。
[Porosity (%), D50 (μm), D10 (μm) and D90 (μm)]
The porosity (%), D50 (μm), D10 (μm) and D90 (μm) of the partition wall were measured using Autopore 9500 (trade name) manufactured by Micromeritics. The values of D50 (μm), D10 (μm) and D90 (μm) were obtained by confirming the pore sizes (μm) at which the cumulative pore volume was 50%, 10% and 90% of the total pore volume in the pore size distribution of the partition wall. In these measurements, a part of the partition wall was cut out from the honeycomb filter to prepare a test piece, and the measurements were performed using the obtained test piece. The test piece was a rectangular parallelepiped with lengths of about 10 mm, about 10 mm and about 20 mm in length, width and height, respectively. The test piece was taken from the vicinity of the center in the axial direction of the honeycomb structure.

[隔壁濡れ面積比]
これまでに説明した方法にて、ハニカム構造体の隔壁に対してCTスキャンを行うことにより、図4に示すような3次元のボクセルデータ60を得た。そして、得られた3次元のボクセルデータ60を用いて、上述した方法に従って隔壁濡れ面積比を算出した。
[Partition wall wetted area ratio]
By performing a CT scan on the partition walls of the honeycomb structure by the method described above, three-dimensional voxel data 60 as shown in Fig. 4 was obtained. Then, using the obtained three-dimensional voxel data 60, the partition wall wet area ratio was calculated according to the method described above.

Figure 2024155787000002
Figure 2024155787000002

実施例1のハニカムフィルタについて、以下の方法で、圧力損失、浄化性能、捕集性能の評価を行った。結果を表1に示す。 The honeycomb filter of Example 1 was evaluated for pressure loss, purification performance, and collection performance using the following methods. The results are shown in Table 1.

(圧力損失)
大型風洞試験機を用いて、25℃のガスを、10Nm/分の流量で流入させて、ハニカムフィルタの流入端面側と流出端面側との圧力を測定した。そして、流入端面側と流出端面側との圧力差を算出することにより、ハニカムフィルタの圧力損失(kPa)を求めた。そして、比較例1のハニカムフィルタの圧力損失の値に対する、各実施例のハニカムフィルタの圧力損失の増加率(%)を求めた。圧力損失の評価においては、下記評価基準に基づき、各実施例のハニカムフィルタの評価を行った。
評価「良」:圧力損失の増加率(%)が10%未満である場合、その評価を「良」とする。
評価「不可」:圧力損失の増加率(%)が10%以上の場合、その評価を「不可」とする。
(Pressure loss)
Using a large wind tunnel testing machine, gas at 25°C was introduced at a flow rate of 10 Nm3 /min to measure the pressure at the inlet end face side and the outlet end face side of the honeycomb filter. The pressure loss (kPa) of the honeycomb filter was then obtained by calculating the pressure difference between the inlet end face side and the outlet end face side. The increase rate (%) of the pressure loss of the honeycomb filter of each Example relative to the pressure loss value of the honeycomb filter of Comparative Example 1 was then obtained. In the evaluation of pressure loss, the honeycomb filters of each Example were evaluated based on the following evaluation criteria.
Evaluation "Good": If the increase rate (%) of pressure loss is less than 10%, the evaluation is "Good".
Evaluation: "Fail": If the increase rate (%) of pressure loss is 10% or more, the evaluation is "Fail".

(浄化性能)
三元触媒を100g/L担持させたハニカムフィルタを、排気量が1500ccの車両の床下位置に搭載し、走行モードRTS95サイクルでの台上試験を行いハニカムフィルタのNOx浄化率(%)を求めた。そして、比較例1のハニカムフィルタのNOx浄化率(%)の値に対して、各実施例のハニカムフィルタのNOx浄化率(%)を比較することで、浄化性能の評価を行った。具体的には。浄化性能の評価においては、下記評価基準に基づき、各実施例のハニカムフィルタの評価を行った。
評価「優」:比較例1のハニカムフィルタのNOx浄化率(%)の値に対して、NOx浄化率(%)が1.0%以上の向上が見られる場合、その評価を「優」とする。
評価「良」:比較例1のハニカムフィルタのNOx浄化率(%)の値に対して、NOx浄化率(%)が0.5%以上1.0%未満の向上が見られる場合、その評価を「良」とする。
評価「不可」:比較例1のハニカムフィルタのNOx浄化率(%)の値に対して、NOx浄化率(%)が0.5%未満の向上が見られる場合、その評価を「不可」とする。
(Purification performance)
A honeycomb filter carrying 100 g/L of a three-way catalyst was mounted under the floor of a vehicle with an engine displacement of 1500 cc, and a bench test was performed in a driving mode RTS 95 cycle to determine the NOx purification rate (%) of the honeycomb filter. The NOx purification rate (%) of the honeycomb filter of each example was compared with the value of the NOx purification rate (%) of the honeycomb filter of Comparative Example 1 to evaluate the purification performance. Specifically, the honeycomb filter of each example was evaluated in the evaluation of the purification performance based on the following evaluation criteria.
Evaluation "Excellent": When the NOx purification rate (%) is improved by 1.0% or more compared to the NOx purification rate (%) of the honeycomb filter of Comparative Example 1, the evaluation is "Excellent".
Evaluation "good": When the NOx purification rate (%) is improved by 0.5% or more and less than 1.0% compared to the NOx purification rate (%) of the honeycomb filter of Comparative Example 1, the evaluation is "good".
Evaluation "Fail": When the NOx purification rate (%) is improved by less than 0.5% compared to the NOx purification rate (%) of the honeycomb filter of Comparative Example 1, the evaluation is "Fail".

(捕集性能)
ハニカムフィルタを、排気量が1500ccの車両の床下位置に搭載し、走行モードRTS95サイクルでの台上試験を行い、ハニカムフィルタにPMを含む排ガスを流した。このとき、ハニカムフィルタに流入する前の排ガス中のPM数、ハニカムフィルタから流出する排ガス中のPM数を測定することでハニカムフィルタの捕集効率(%)を求めた。捕集性能の評価においては、下記評価基準に基づき、各実施例のハニカムフィルタの評価を行った。
評価「良」:捕集効率(%)が70%以上の場合、その評価を「良」とする。
評価「可」:捕集効率(%)が65%以上、70%未満の場合、その評価を「可」とする。
評価「不可」:捕集効率(%)が65%未満の場合、その評価を「不可」とする。
(Collection performance)
The honeycomb filter was mounted under the floor of a vehicle with a displacement of 1500 cc, and a bench test was performed in a driving mode RTS95 cycle, and exhaust gas containing PM was passed through the honeycomb filter. At this time, the number of PM in the exhaust gas before it flowed into the honeycomb filter and the number of PM in the exhaust gas flowing out from the honeycomb filter were measured to obtain the collection efficiency (%) of the honeycomb filter. In the evaluation of the collection performance, the honeycomb filters of each Example were evaluated based on the following evaluation criteria.
Evaluation "good": When the collection efficiency (%) is 70% or more, the evaluation is rated as "good".
Evaluation "Fair": When the collection efficiency (%) is 65% or more and less than 70%, the evaluation is "Fair".
Evaluation "Fail": When the collection efficiency (%) is less than 65%, the evaluation is rated as "Fail".

(実施例2~4)
実施例2~4においては、ハニカム構造体の構成を、表1の「隔壁の特性」に示すように変更した。なお、実施例2,4においては、原料粉末に添加する造孔材の粒径をより小さくしてハニカム構造体を作製した。実施例3においては、原料粉末に添加する造孔材の粒径をより大きくしてハニカム構造体を作製した。
(Examples 2 to 4)
In Examples 2 to 4, the configuration of the honeycomb structure was changed as shown in "Partition wall characteristics" in Table 1. In Examples 2 and 4, the honeycomb structure was manufactured by adding a smaller particle size of the pore-forming material to the raw material powder. In Example 3, the honeycomb structure was manufactured by adding a larger particle size of the pore-forming material to the raw material powder.

(比較例1)
比較例1においては、ハニカム構造体の構成を、表1の「隔壁の特性」に示すように変更した。なお、比較例1においては、造孔材の粒子径、及びその添加量を調節することにより小細孔容積が少なくなるようなハニカム構造体を作製した。
(Comparative Example 1)
In Comparative Example 1, the configuration of the honeycomb structure was changed as shown in "Partition wall characteristics" in Table 1. In Comparative Example 1, a honeycomb structure was produced in which the small pore volume was reduced by adjusting the particle size of the pore-forming material and the amount of the pore-forming material added.

実施例2~4のハニカムフィルタについても、実施例1と同様の方法で、圧力損失、浄化性能、捕集性能の評価を行った。結果を表1に示す。なお、比較例1のハニカムフィルタは、圧力損失及び浄化性能の評価において評価基準となっている。 The honeycomb filters of Examples 2 to 4 were also evaluated for pressure loss, purification performance, and collection performance in the same manner as in Example 1. The results are shown in Table 1. The honeycomb filter of Comparative Example 1 was used as the evaluation standard for pressure loss and purification performance.

(結果)
実施例1~4のハニカムフィルタは、圧力損失、及び浄化性能の評価において、評価基準となる比較例1のハニカムフィルタよりも優れた結果を示すものであった。特に、実施例4のハニカムフィルタは、隔壁濡れ面積比が0.3m/mであり、浄化性能の評価結果が特に優れたものであった。実施例1,3のハニカムフィルタは、隔壁濡れ面積比が同等の値を示すものであったが、詳細な捕集性能を比較したところ、実施例1のハニカムフィルタの方がより優れた捕集性能を示すことが分かった。実施例1のハニカムフィルタは、D90の値が実施例3のハニカムフィルタよりも小さく、捕集性能の改善が図られたものと推察される。
(result)
The honeycomb filters of Examples 1 to 4 showed superior results in the evaluation of pressure loss and purification performance to the honeycomb filter of Comparative Example 1, which was the evaluation standard. In particular, the honeycomb filter of Example 4 had a partition wall wet area ratio of 0.3 m 2 /m 2 and showed particularly excellent evaluation results for purification performance. The honeycomb filters of Examples 1 and 3 showed equivalent partition wall wet area ratios, but when the collection performance was compared in detail, it was found that the honeycomb filter of Example 1 showed superior collection performance. The honeycomb filter of Example 1 had a smaller D90 value than the honeycomb filter of Example 3, and it is presumed that the collection performance was improved.

本発明のハニカムフィルタは、排ガス中の粒子状物質を捕集するフィルタとして利用することができる。 The honeycomb filter of the present invention can be used as a filter to capture particulate matter in exhaust gas.

1:隔壁、2:セル、2a:流入セル、2b:流出セル、3:外周壁、4:ハニカム構造体、5:目封止部、11:流入端面、12:流出端面、60:ボクセルデータ、64:拡大図、100:ハニカムフィルタ。 1: Partition wall, 2: Cell, 2a: Inlet cell, 2b: Outlet cell, 3: Outer wall, 4: Honeycomb structure, 5: Plugged portion, 11: Inlet end face, 12: Outlet end face, 60: Voxel data, 64: Enlarged view, 100: Honeycomb filter.

Claims (3)

流入端面から流出端面まで延びる流体の流路となる複数のセルを取り囲むように配置された多孔質の隔壁を有する柱状のハニカム構造体と、
前記セルの前記流入端面側の端部又は前記流出端面側の端部のいずれか一方に配設された目封止部と、を備え、
前記隔壁の厚さが、152~254μmであり、
前記ハニカム構造体のセル密度が、38.8~62.0個/cmであり、
水銀圧入法によって測定された前記隔壁の細孔径分布において、累積細孔容積が全細孔容積の50%となる細孔径D50が、11~15μmであり、
水銀圧入法によって測定された前記隔壁の気孔率が、60~75%であり、
多孔質の前記隔壁内に形成された気孔の濡れ面積Aを、当該気孔の断面積Sで除した値である隔壁濡れ面積比(A/S)が、0.21~0.35m/mである、ハニカムフィルタ。
a columnar honeycomb structure having porous partition walls arranged to surround a plurality of cells that serve as fluid flow paths extending from an inflow end face to an outflow end face;
A plugging portion is provided at either one of the end portion on the inlet end surface side or the end portion on the outlet end surface side of the cell,
The thickness of the partition wall is 152 to 254 μm,
The honeycomb structure has a cell density of 38.8 to 62.0 cells/ cm2 ;
In a pore size distribution of the partition walls measured by mercury intrusion porosimetry, a pore size D50 at which a cumulative pore volume becomes 50% of a total pore volume is 11 to 15 μm,
the porosity of the partition walls measured by mercury porosimetry is 60 to 75%,
A honeycomb filter, wherein a partition wall wet area ratio (A/S), which is a value obtained by dividing a wet area A of a pore formed in the porous partition wall by a cross-sectional area S of the pore, is 0.21 to 0.35 m 2 /m 2 .
水銀圧入法によって測定された前記隔壁の前記細孔径分布において、累積細孔容積が全細孔容積の10%となる細孔径D10が、5.5~7.5μmである、請求項1に記載のハニカムフィルタ。 The honeycomb filter according to claim 1, wherein the pore diameter D10 at which the cumulative pore volume is 10% of the total pore volume in the pore diameter distribution of the partition walls measured by mercury intrusion porosimetry is 5.5 to 7.5 μm. 水銀圧入法によって測定された前記隔壁の前記細孔径分布において、累積細孔容積が全細孔容積の90%となる細孔径D90が、35.0μm以下である、請求項1又は2に記載のハニカムフィルタ。

3. The honeycomb filter according to claim 1, wherein in the pore size distribution of the partition walls measured by mercury intrusion porosimetry, a pore size D90 at which a cumulative pore volume is 90% of a total pore volume is 35.0 μm or less.

JP2024065167A 2023-04-21 2024-04-15 Honeycomb Filter Pending JP2024155787A (en)

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JP2005530616A (en) * 2002-06-26 2005-10-13 コーニング インコーポレイテッド Aluminum magnesium silicate structure for DPF applications
JP2007525612A (en) * 2003-06-25 2007-09-06 コーニング・インコーポレーテッド Cordierite filter with reduced pressure loss
JP2016187793A (en) * 2015-03-30 2016-11-04 日本碍子株式会社 Honeycomb structure and method for producing the same
JP2017170396A (en) * 2016-03-25 2017-09-28 日本碍子株式会社 Honeycomb structure
JP2020182887A (en) * 2019-04-26 2020-11-12 株式会社デンソー Exhaust gas purification filter

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005530616A (en) * 2002-06-26 2005-10-13 コーニング インコーポレイテッド Aluminum magnesium silicate structure for DPF applications
JP2007525612A (en) * 2003-06-25 2007-09-06 コーニング・インコーポレーテッド Cordierite filter with reduced pressure loss
JP2016187793A (en) * 2015-03-30 2016-11-04 日本碍子株式会社 Honeycomb structure and method for producing the same
JP2017170396A (en) * 2016-03-25 2017-09-28 日本碍子株式会社 Honeycomb structure
JP2020182887A (en) * 2019-04-26 2020-11-12 株式会社デンソー Exhaust gas purification filter

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