JP2007007559A - Ceramic honeycomb filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a honeycomb filter in which the number of both side sealed passages is reduced by appropriately arranging the both side sealed passages constituting a resonance pipe and the number of outflowing side sealed passages is increased and PM collecting capacity is increased without reducing a muffling function as much as possible. <P>SOLUTION: This ceramic honeycomb filter has an inflowing side sealed passage in which an exhaust gas inflowing side of the passage surrounded by a partition wall of ceramic honeycomb structure and having a square cross section is sealed with a sealing part, the outflowing side sealed passage in which an outflowing side is sealed with the sealing part and the both side sealed passage in which both the inflowing side and the outflowing side are sealed with the sealing parts. In this ceramic honeycomb filter, all eight passages surrounding the both side sealed passage are the inflowing side sealed passages or the outflowing side sealed passages and further at least two inflowing side sealed passages or the outflowing side sealed passages are provided between two both side sealed passages standing in a line in a stretching direction of the partition wall on a passage cross section of a vertical direction. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a ceramic honeycomb filter used for purifying exhaust gas containing particulate matter discharged from a diesel engine.

  Exhaust gases such as diesel engines contain a large amount of PM (Particulate Matter) mainly composed of carbon, and if this is released into the atmosphere, it will adversely affect the human body and the environment. For this reason, an exhaust gas system such as a diesel engine is equipped with a filter for collecting and purifying PM.

  FIG. 1 shows an example of a conventional ceramic honeycomb filter (hereinafter abbreviated as “honeycomb filter”) 10 that collects and purifies PM in exhaust gas, and (a) is viewed from the inflow side. The schematic diagram of a honey-comb filter, (b) is a cross-sectional schematic diagram along line AA. In FIG. 1, the honeycomb filter 10 includes an outer peripheral wall 1 whose section perpendicular to the flow path direction of the honeycomb filter is substantially circular or substantially elliptical, and a large number of walls surrounded by partition walls 2 on the inner peripheral side of the outer peripheral wall 1. A ceramic honeycomb structure (1) having a flow path (hereinafter referred to as “honeycomb structure” for short) is formed by sealing portions 5 and 6 on the exhaust gas inflow end surface 7 and the outflow side end surface 8 respectively. By alternately plugging, the outflow side sealed flow path 3 and the inflow side sealed flow path 4 are formed. The outer peripheral wall is shown as 1, and the honeycomb structure is shown as (1).

  In the honeycomb filter 10 of FIG. 1, exhaust gas purification is performed as follows. Exhaust gas (indicated by a dotted arrow) flows in from the outflow side sealing flow path 3 opened in the inflow side end surface 7. The PM contained in the exhaust gas is collected on the inside and the surface of the partition wall 2 when passing through the partition wall 2, and the purified exhaust gas flows into the inflow side sealed flow opening in the outflow side end face 8. It flows out of the road 4 and is released into the atmosphere.

  Here, when the amount of PM trapped in the inside and the surface of the partition wall 2 increases, PM accumulates in the outflow side sealing flow path 3 and the partition wall is clogged to increase the pressure loss. Before this increases, it is necessary to regenerate the honeycomb filter 10 by burning and removing PM.

  By the way, in contrast to the basic honeycomb filter shown in FIG. 1, Patent Document 1 describes a honeycomb filter to which a silencing function is added. FIG. 2 shows an example of the honeycomb filter described in Patent Document 1, wherein (a) is a schematic view of the honeycomb filter viewed from the inflow side, and (b) is a schematic cross-sectional view along line CC. In FIG. 2, 3 is an outflow side sealed flow path, 4 is an inflow side sealed flow path, and 4C is a both-side sealed flow path in which both the inflow side and the outflow side of the flow path are sealed. Further, in FIG. 2A, the hatching of the inflow side sealed flow path 4 indicates the sealed portion 5 on the inflow side of the flow path. It shows that the inflow side sealing portion 5 and the outflow side sealing portion 6 are plugged. Here, it is said that a honeycomb filter having a silencing function can be obtained by making the both-side sealed flow path function as a resonance chamber.

JP 2003-254035 A

  However, in the case of the honeycomb filter 20 having the silencing function shown in FIG. 2 described in Patent Document 1, the number of the inflow side sealing flow paths 4 is the same as the number of the both-side sealed flow paths 4C compared to the honeycomb filter shown in FIG. The number of outflow side sealing flow paths 3 decreases. Since PM is collected on the surface and inside of the partition wall constituting the outflow side sealing flow path 3, if the number of outflow side sealing flow paths 3 is small, the PM can be put into the outflow side sealing flow path 3 in a short time. As a result, the partition wall 2 is clogged and the pressure loss increases, and the regeneration interval of the honeycomb filter needs to be shortened. As a method of regenerating the honeycomb filter, a method of burning PM with an electric heater, a burner, a microwave, or the like is used. However, in any method, when the regeneration interval is shortened, energy consumption increases.

  Naturally, if the number of both-side sealed flow paths 4C is reduced and the number of outflow-side sealed flow paths 3 is increased, the amount of PM trapped until the honeycomb filter needs to be regenerated (hereinafter, the honeycomb filter needs to be regenerated). (PM collection capacity is abbreviated as “PM collection capacity”), so that the regeneration interval can be extended, but the silencing function is reduced. Patent Document 1 describes that the arrangement and ratio of the inflow side sealing channel, the outflow side sealing channel, and the both side sealing channels can be freely changed, but both sides sealing without reducing the silencing function as much as possible. The specific arrangement and ratio of increasing the number of outflow side sealing channels 3 by reducing the number of stop channels 4C are not presented.

  Therefore, an object of the present invention is to reduce the number of both-side sealed channels by increasing the number of both-side sealed channels and to increase the number of outflow-side sealed channels, and to reduce PM without reducing the silencing function as much as possible. The object is to obtain a honeycomb filter having an increased collection capacity.

  The present invention relates to an inflow side sealed flow path in which an exhaust gas inflow side of a flow path surrounded by partition walls of a ceramic honeycomb structure has a quadrangular shape is plugged with a sealing part, and an outflow side is a sealing part In a ceramic honeycomb filter having an outflow side sealing flow path plugged with a plug and both side sealing flow paths in which both the inflow side and the outflow side are plugged with a sealing portion, All of the flow paths are inflow side sealed flow paths or outflow side sealed flow paths, and between the two side sealed flow paths that exist side by side in the extending direction of the partition wall on the cross section in the vertical direction of the flow path. It has at least two inflow side sealed flow paths or outflow side sealed flow paths.

  Here, the eight channels surrounding the both-side sealed channels refer to eight channels surrounding the both-side sealed channels 4C in the schematic vertical sectional view of the honeycomb filter shown in FIG. Further, the extending direction of the partition wall on the cross section in the vertical direction of the flow path means two arrow directions shown in FIG. Further, the quadrangular shape of the cross section of the flow path is not limited to a square, a rectangle, a trapezoid, a parallelogram, or the like, but may be a shape having four corner portions formed by intersecting partition walls in the cross section in the vertical direction of the flow path. That's fine.

  Further, according to the present invention, the inflow side sealing portion of the inflow side sealing flow channel and the inflow side sealing portion of the both side sealing flow channels are arranged apart from the exhaust gas inflow side end surface of the ceramic honeycomb structure. In addition, it is preferable that the inflow side sealed flow channel and the both side sealed flow channels are not adjacent to the extending direction of the partition wall on the flow channel vertical cross section.

(Function)
The operation of the present invention will be described with reference to the drawings. First, FIG. 2 shows a honeycomb filter described in Patent Document 1. Here, (a) is a schematic diagram of the honeycomb filter as viewed from the inflow side end face, and (b) is a schematic cross-sectional view along line CC. Further, 2 is a partition wall, 5 and 6 are sealing portions, 3 is an outflow side sealing flow path, 4 is an inflow side sealing flow path, and 4C is a double-side sealed flow path. In the case of the honeycomb filter shown in FIG. 2, 1/4 of the total number of flow paths is the outflow side sealed flow path, that is, 25% of the total number of flow paths is present. Since it is the outflow side sealing flow path 3, the PM collection capacity is small. In order to increase the PM collection capacity, it is only necessary to decrease the number of both-side sealed channels and increase the number of outflow-side sealed channels, but simply decrease the number of both-side sealed channels 4C, For example, if the both-side sealed flow path 4C is reduced to half as shown in the schematic diagram of FIG. 4, the noise collection function is greatly reduced although the PM collection capacity is increased. The reason for this is that out of the exhaust gas flowing into the outflow side sealing flow channel 3H, for example, the exhaust gas flowing through the partition wall 2 into the inflow side sealing flow channels 4I and 4J out of the outflow side sealing flow channel 3H This is because the honeycomb filter is discharged without touching the partition wall surrounding the both-side sealed flow paths 4C constituting the resonance tube. Further, since the two side sealed channels are adjacent to each other so as to share two of the four partition walls surrounding one channel, the silencing function of the both side sealed channels is not effectively exhibited.

  When the both-side sealed flow path 4C is shifted from the extending direction of the partition wall by 45 ° as shown in FIG. 5 while avoiding the above reasons, the exhaust gas must be sealed on both sides inside the honeycomb filter. Although the silencing function can be effectively exhibited because it touches the partition wall surrounding the flow path, the number of outflow side sealed flow paths 3 is 25% of the total number of flow paths, and the PM collection capacity is small.

  Next, an example of the honeycomb filter of the present invention is shown in FIG. Here, (a) is a schematic view of the honeycomb filter viewed from the inflow side, and (b) is a schematic cross-sectional view along the line FF. In the honeycomb filter 60 shown in FIG. 6, the eight flow paths surrounding the both-side sealed flow paths 4 </ b> C are all inflow side sealed flow paths 4 or outflow side sealed flow paths 3. Further, at least two inflow side sealing channels 4 or outflow side seals are provided between two two-sided sealing channels 4C (for example, 4CA and 4CB) existing side by side in the extending direction of the partition wall 2 on the channel vertical cross section. A stop channel 3 is provided. By arranging the both-side sealed flow paths 4C in this way, the number of outflow side sealed flow paths 3 is about 42% with respect to the total number of flow paths. In the honeycomb filter shown in FIGS. 2 and 5, the number of outflow side sealing channels 3 with respect to the total number of channels is 25%. In the honeycomb filter shown in FIG. 4, the outflow side sealing channels with respect to the number of all channels. Since the number of 3 is 37%, the PM collection capacity of the honeycomb filter 60 of the present invention is greatly increased. Further, since the exhaust gas always comes into contact with the partition wall surrounding the both-side sealed flow path inside the honeycomb filter, the silencing function is effectively exhibited as in the honeycomb filter shown in FIG.

  FIG. 7 shows another example of the honeycomb filter of the present invention. Here, (a) is a schematic view of the honeycomb filter viewed from the inflow side, and (b) is a schematic cross-sectional view along the line GG. In the filter 70 shown in FIG. 7, all the eight flow paths surrounding the both-side sealed flow paths 4 </ b> C are the inflow side sealed flow paths 4 or the outflow side sealed flow paths 3. Further, there are three inflow side sealing channels 4 or outflow side sealing channels 3 between the two side sealing channels 4C existing side by side in the extending direction of the partition wall 2 on the channel vertical cross section. ing. By arranging the both-side sealed flow paths 4C in this way, the number of outflow-side sealed flow paths 3 is further increased to 50% with respect to the total number of flow paths, and the PM collection capacity of the honeycomb filter is as described above. Compared with the honeycomb filter 60 shown in FIG. Further, since the exhaust gas always comes into contact with the partition wall surrounding the both-side sealed flow paths 4C inside the honeycomb filter 70, the silencing function is effectively exhibited as in the honeycomb filter shown in FIG.

  In the present invention, the inflow side sealed flow path 4 or the outflow side sealed flow path 3 existing between the two side sealed flow paths 4C existing side by side in the extending direction of the partition wall 2 on the flow path vertical cross section. It is also possible to increase the number. It is also possible to change the both-side sealed flow path 4C to the inflow side sealed flow path 4 or the outflow side sealed flow path 3. As a result, the number of the both-side sealed flow paths 4C constituting the resonance tube is reduced, so that the silencing function is reduced. However, the both-side sealed flow paths 4C are all inflow side sealed flow paths 4 or outflow side sealed with the partition wall 2 interposed therebetween. Since it is in contact with the stop channel 3, it is possible to collect the PM while effectively exhibiting the silencing effect.

  Moreover, in this invention, a sealing part can also be provided in the inside of both-side sealing flow path 4C. Thereby, resonance tubes having different resonance frequencies can be configured.

  FIG. 8 shows another example of the honeycomb filter of the present invention. Here, (a) is a schematic view of the honeycomb filter viewed from the outflow side, and (b) is a schematic cross-sectional view along the line HH. In the honeycomb filter shown in FIG. 8, the inflow side sealing portion 5 of the inflow side sealing channel 4 and the inflow side sealing portion 5 of the both side sealing channels 4C are arranged apart from the inflow side end surface 7. Yes. As a result, PM can also be collected on the inflow side of the inflow side sealing portion, and the PM collection capacity further increases. Further, the inflow side sealing flow path 4 and the both side sealing flow paths 4C are not adjacent to each other with the partition wall 2 interposed in the extending direction of the partition wall on the cross section in the flow channel vertical direction. As a result, the inflow side sealing flow path 4 and the both side sealing flow paths 4C are adjacent to each other with only the outflow side sealing flow path 3 through which the exhaust gas having a high temperature flows through the partition wall 2. 4 and PM deposited on the inflow side end surfaces of the inflow side sealing portions 5 of the both side sealed flow paths 4C are easily burned and removed.

  According to the honeycomb filter of the present invention, by properly arranging the both-side sealed flow paths constituting the resonance tube, the number of both-side sealed flow paths is reduced, the number of outflow-side sealed flow paths is increased, and the muffler function is provided. A honeycomb filter having an increased PM collection capacity without being reduced as much as possible can be obtained.

Hereinafter, several examples of embodiments of the present invention will be described in detail with reference to the drawings.
(Embodiment 1)
6A and 6B show the honeycomb filter 60 according to Embodiment 1. FIG. 6A is a schematic diagram of the honeycomb filter viewed from the inflow side, and FIG. 6B is a schematic cross-sectional view taken along line FF. The basic structure of the honeycomb filter 60 and the arrangement pattern of the both-side sealed flow paths 40C are as described in the means for solving the above problems. That is, in the honeycomb filter 60 shown in FIG. 6, all the eight flow paths surrounding the both-side sealed flow paths 4C are the inflow side sealed flow paths 4 or the outflow side sealed flow paths 3, and Thus, at least two inflow side sealing channels 4 or outflow side sealing channels 3 are provided between the two side sealing channels 4C existing side by side in the extending direction of the partition wall 2. The honeycomb filter 60 according to Embodiment 1 can be obtained as follows. First, kaolin, talc, silica, aluminum hydroxide, to adjust the powder, such as alumina, in a mass _{ratio, SiO 2: 47~53%, Al} 2 O 3: 33~38%, MgO: 12~16%, And a cordierite-producing raw material powder containing 2.5% or less in total of components inevitably mixed such as CaO, Na ₂ O, K ₂ O, TiO _2, Fe ₂ O ₃ , PbO, and P ₂ O ₅ To this, add graphite, methylcellulose, hydroxypropylmethylcellulose, and other binders, graphite, and pore-forming material, mix thoroughly in a dry process, add a specified amount of water, and perform sufficient kneading to plasticize the ceramic cup. Make soil. Next, the kneaded material is extruded using an extrusion molding die and cut to obtain a formed body having a honeycomb structure. Next, the molded body is dried and fired, the outer diameter of the outer peripheral wall 1 is 267 mm, the total length L is 300 mm, the partition walls 2 are 0.3 mm thick, 1.57 mm pitch, 65% porosity, average pore diameter A cordierite honeycomb structure with a thickness of 20 μm is used. The total number of channels of the honeycomb structure (1) is about 25,000.

  Next, sealing portions are formed at both ends of the honeycomb structure by a known method. First, a resin sealing film is attached to the inflow side end face 7 of the honeycomb structure (1). Next, a sealing film at a position where the inflow side sealing portion 5 is formed is perforated. At this time, the sealing portion 5 on the inflow side is made to have a pattern shown in FIG. Next, the inflow side end face 7 of the honeycomb structure (1) is immersed in a slurry-like sealing material, and the sealing material is filled into the flow path through the perforations. Thereafter, after the sealing material is deposited on the partition wall 2 and the shape retention is obtained, the sealing film is removed and the sealing material is dried. Subsequently, in the same manner as described above, the sealing material 6 is filled from the outflow side end face 8 of the honeycomb structure (1) so that the sealing portion 6 has the pattern shown in FIG. 6A, and the sealing film is removed. The sealing material is dried. Thereafter, the honeycomb structure (1) is fired together with the sealing material while controlling the temperature using a batch-type firing furnace, whereby the honeycomb filter 60 shown in FIG. 6 is obtained. The number of both-side sealed flow paths 4C of the honeycomb filter 60 is 42% with respect to the total number of flow paths.

  In order to make it difficult for heat when PM burns to be transmitted to the outside through the outer peripheral wall 1, a heat insulating layer having a sealing portion may be provided at both ends of the flow path of the outer peripheral portion of the honeycomb structure. The flow paths with both ends sealed are adjacent to each other in order to provide a heat insulating function, and are different from the flow paths constituting the resonance tube of the present invention.

(Comparative example)
Next, as a comparative example, the same structure as the honeycomb structure (1) of FIG. 6 is used, except that the flow path for forming the inflow side sealing portion 5 and the outflow side sealing portion 6 is changed, and the inflow side sealing is performed. The honeycomb filter 50 was manufactured such that the stop channel 4, the outflow side sealing channel 3, and the both side sealing channel 4C were arranged in the pattern shown in FIG. The number of both-side sealed channels 4C of the honeycomb filter 50 is 25% with respect to the total number of channels. When the PM collection capacity of the honeycomb filter 60 shown in the first embodiment and the honeycomb filter 50 shown in the comparative example are compared, the PM collection capacity of the honeycomb filter 60 shown in the first embodiment is the honeycomb filter 50 shown in the comparative example. It was possible to increase to 160%. Moreover, the silencing function of the honeycomb filter 60 shown in the first embodiment and the honeycomb filter 50 shown in the comparative example was almost the same.

Here, the PM collection capacity is measured as follows. First, the honeycomb filter 50 of the comparative example is mounted on a pressure loss measuring device, and air is passed through the honeycomb filter 50 in an amount of 10 Nm ³ / min, and the initial pressure loss is measured. Next, the pressure loss is measured while introducing carbon powder having a particle size of 0.042 μm into the honeycomb filter in small portions at a rate of 3 g / min together with the same air amount as described above. The weight of the carbon powder charged into the honeycomb filter 50 by the time when the pressure loss value reaches 125% of the initial pressure loss quality is defined as the PM collection capacity of the honeycomb filter 50, and the pressure loss value at this time is defined as K. And Next, the honeycomb filter 60 shown in the first embodiment is mounted on the pressure loss measuring device, and the pressure loss is measured while introducing small amounts of carbon powder together with air into the honeycomb filter in the same manner as described above. The weight of the carbon powder charged into the honeycomb filter 60 up to the time point becomes the PM collection capacity of the honeycomb filter 60.

(Embodiment 2)
7A and 7B show the honeycomb filter 70 according to the second embodiment, where FIG. 7A is a schematic diagram of the honeycomb filter viewed from the inflow side, and FIG. 7B is a schematic cross-sectional view taken along line GG. The manufacturing method of the honeycomb filter 70 is the same as that of the honeycomb filter 60 according to Embodiment 1, but the arrangement of the outflow side sealing flow path 3, the inflow side sealing flow path 4, and the both side sealing flow paths 4C is shown in FIG. Only the perforation pattern of the sealing film was changed to produce the pattern shown. In the honeycomb filter 70 manufactured as described above, the number of outflow side sealing channels is 50% of the total number of channels, and the PM collection capacity is 110% compared to the honeycomb filter 60 shown in the first embodiment. It could be increased further. Further, the silencing function of the honeycomb filter 70 shown in the second embodiment and that of the honeycomb filter 60 shown in the first embodiment are substantially the same.

(Embodiment 3)
8A and 8B show the honeycomb filter 80 according to the third embodiment. FIG. 8A is a schematic view of the honeycomb filter viewed from the inflow side, and FIG. 8B is a schematic cross-sectional view taken along line HH. Compared with the honeycomb filter 70 shown in the second embodiment, the honeycomb filter 80 has a configuration in which the sealing portion 5 of the inflow side sealing flow path 4 and the inflow side sealing portion 5 of the both side sealing flow paths 4C are the honeycomb filter. It is the same except that it is arrange | positioned away from the inflow side end surface 7 of no. The manufacturing method of the honeycomb filter 80 of the third embodiment is the same except for the manufacturing method of the sealing portion 5 of the inflow side sealing flow path 4 and the inflow side sealing portion 5 of the both side sealing flow paths 4C. is there.

  The sealing part 5 of the inflow side sealing flow path 4 of the honeycomb filter 80 and the sealing part 5 on the inflow side of the both side sealing flow paths 4C are configured by inserting a syringe-like tube into the flow path. It can be manufactured by introducing a pasty sealing material as a material into a desired position away from the inflow side end face 7.

  In the honeycomb filter 80 manufactured as described above, the number of outflow side sealing channels is 50% with respect to the total number of channels, and the PM collection capacity is 140% with respect to the honeycomb filter 70 shown in the second embodiment. It could be increased further. Further, the silencing function of the honeycomb filter 80 shown in the third embodiment and that of the honeycomb filter 70 shown in the second embodiment are substantially the same. In addition, as a manufacturing method of the sealing part 5 of the inflow side sealing flow path 4 and the sealing part 5 on the inflow side of the both side sealing flow paths 4C which are arranged apart from the inflow side end face 7, honeycomb structure (1) Is cut and separated in the direction perpendicular to the flow path at the position where the sealing portion 5 is disposed, and the sealing portion is disposed using a known method of providing the sealing portion on the end face of the honeycomb structure, and then a bonding material is used. The honeycomb structure separated in this manner can be obtained by joining and integrating again.

A conventional honeycomb filter is shown, (a) is a schematic view of the honeycomb filter viewed from the inflow side, and (b) is a schematic cross-sectional view along line AA. The honeycomb filter proposed in Patent Document 1 is shown, in which (a) is a schematic view of the honeycomb filter viewed from the inflow side, and (b) is a schematic cross-sectional view along line CC. It is a figure explaining the meaning of the extending direction of the above-mentioned partition on the eight channel which encloses both sides sealing channel, and a channel perpendicular direction section. 4 is a honeycomb filter showing an example in which the number of both-side sealed channels is reduced with respect to the honeycomb filter shown in FIG. 4, (a) is a schematic diagram of the honeycomb filter viewed from the inflow side, and (b) is a line DD. It is a cross-sectional schematic diagram along line. It is a honeycomb filter which concerns on a comparative example, (a) is a schematic diagram of the honeycomb filter seen from the inflow side, (b) is a cross-sectional schematic diagram along line EE. 1 is a honeycomb filter according to Embodiment 1, wherein (a) is a schematic view of the honeycomb filter viewed from the inflow side, and (b) is a schematic cross-sectional view taken along line FF. 4 is a honeycomb filter according to Embodiment 2, wherein (a) is a schematic view of the honeycomb filter viewed from the inflow side, and (b) is a schematic cross-sectional view taken along line GG. FIG. 4 is a honeycomb filter according to Embodiment 3, wherein (a) is a schematic view of the honeycomb filter viewed from the inflow side, and (b) is a schematic cross-sectional view taken along line FF. FIG.

Explanation of symbols

10, 20, 40, 50, 60, 70, 80: honeycomb filter (ceramic honeycomb filter)
1: Outer peripheral wall (1): Honeycomb structure (ceramic honeycomb structure)
2: Septum 3: Outflow side sealed flow path 4: Inflow side sealed flow path 4C: Both sides sealed flow path 5: Inflow side sealed section 6: Outflow side sealed section 7: Inflow side end face 8: Outflow Side end face

Claims (2)

The flow path surrounded by the partition walls of the ceramic honeycomb structure has a quadrangular cross section, the inflow side sealing flow path in which the exhaust gas inflow side is plugged with the sealing part, and the outflow side is plugged with the sealing part. In the ceramic honeycomb filter having the outflow side sealed flow path and the both side sealed flow paths in which the inflow side and the outflow side are both sealed with a sealing portion, all of the 8 flow paths surrounding the both side sealed flow paths are Inflow side sealing flow path or outflow side sealing flow path, and at least two inflows between the two side sealed flow paths that exist side by side in the extending direction of the partition wall on the cross section in the vertical direction of the flow path A ceramic honeycomb filter having a side sealing flow path or an outflow side sealing flow path. The inflow side sealing portion of the inflow side sealing flow channel and the inflow side sealing portion of the both side sealing flow channels are disposed apart from the exhaust gas inflow side end surface of the ceramic honeycomb structure, and the inflow side 2. The ceramic honeycomb filter according to claim 1, wherein the sealing flow path and the both-side sealed flow paths are not adjacent to each other in the extending direction of the partition walls on the cross section in the flow path vertical direction.

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