JP3611213B2 - Ceramic honeycomb structure - Google Patents
Ceramic honeycomb structure Download PDFInfo
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- JP3611213B2 JP3611213B2 JP2004030688A JP2004030688A JP3611213B2 JP 3611213 B2 JP3611213 B2 JP 3611213B2 JP 2004030688 A JP2004030688 A JP 2004030688A JP 2004030688 A JP2004030688 A JP 2004030688A JP 3611213 B2 JP3611213 B2 JP 3611213B2
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- ceramic honeycomb
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Landscapes
- Exhaust Gas Treatment By Means Of Catalyst (AREA)
- Press-Shaping Or Shaping Using Conveyers (AREA)
- Catalysts (AREA)
- Exhaust Gas After Treatment (AREA)
- Processes For Solid Components From Exhaust (AREA)
- Filtering Materials (AREA)
- Devices For Post-Treatments, Processing, Supply, Discharge, And Other Processes (AREA)
Description
本発明は、自動車等の排気ガス浄化装置に使用されるセラミックハニカム構造体に関し、例えばディーゼルエンジンからの排気ガスを浄化するセラミックハニカム触媒や排気ガス中に含まれる微粒子を捕集するセラミックハニカムフィルタに使用するのに好適なセラミックハニカム構造体に関する。 The present invention relates to a ceramic honeycomb structure used in an exhaust gas purifying apparatus for automobiles, etc., for example, a ceramic honeycomb catalyst for purifying exhaust gas from a diesel engine and a ceramic honeycomb filter for collecting fine particles contained in the exhaust gas. The present invention relates to a ceramic honeycomb structure suitable for use.
ディーゼルエンジンからの排気ガス中に含まれる微粒子を除去するため、セラミックハニカム構造体の隔壁を多孔質構造とし、このハニカム構造体の流路開口部の両端を交互に目封止することにより、微粒子を含んだ排気ガスを前記隔壁に通過せしめる構造の微粒子捕集用のセラミックハニカムフィルタを採用する検討が進められている。 In order to remove the fine particles contained in the exhaust gas from the diesel engine, the partition walls of the ceramic honeycomb structure have a porous structure, and the both ends of the flow path openings of the honeycomb structure are alternately plugged, whereby the fine particles Studies are underway to adopt a ceramic honeycomb filter for collecting fine particles having a structure that allows exhaust gas containing gas to pass through the partition walls.
図１は、排気ガス中の微粒子を捕集するセラミックハニカムフィルタの使用例の一例を示す要部の模式断面概略図である。図１に示すように、セラミックハニカムフィルタ１０は、把持部材１３及び１４を介して、収納容器１２内に収納され、把持部材の面圧により、使用中に動かないように把持されている。通常セラミックハニカムフィルタ１０の端面外周の形状は、ほぼ円筒状で、その外周壁１１ａとこの外周壁１１ａの内周側に各々直交する隔壁１１ｂにより形成された複数の流路１５を有し、この流路１５の両端部が交互に入口側目封止部１ａ、出口側目封止部１ｂで封止されている。 FIG. 1 is a schematic cross-sectional schematic view of the main part showing an example of use of a ceramic honeycomb filter that collects particulates in exhaust gas. As shown in FIG. 1, the ceramic honeycomb filter 10 is accommodated in the storage container 12 via the gripping members 13 and 14, and is held so as not to move during use by the surface pressure of the gripping member. Usually, the shape of the outer periphery of the end face of the ceramic honeycomb filter 10 is substantially cylindrical, and has a plurality of flow paths 15 formed by the outer peripheral wall 11a and the partition walls 11b orthogonal to the inner peripheral side of the outer peripheral wall 11a. Both ends of the flow path 15 are alternately sealed by the inlet side plugged portions 1a and the outlet side plugged portions 1b.
このようなハニカムフィルタでの排気ガス浄化作用は以下の通り行われる。先ず、入口側排気ガス２ａは収納容器１２に収納されたセラミックハニカムフィルタ１０の入口側端面１０ａの開口している流路１５ａから流入し、矢印で示すように、隔壁１１ｂを通過し出口側排気ガス２ｂとして、出口側端面１０ｂの開口している流路１５ｂから排気される。入口側排気ガス２ａが隔壁１１ｂを通過する際に、入口側排気ガス２ａに含まれる微粒子は、隔壁１１ｂに捕捉され、浄化された排気ガスが出口側排気ガス２ｂとして、大気中に放出される。隔壁１１ｂに捕捉された微粒子は一定量以上になるとフィルタの目詰まりが発生するため、バーナーや電気ヒーターにより燃焼させ、フィルタの再生が行われる。 The exhaust gas purification action in such a honeycomb filter is performed as follows. First, the inlet side exhaust gas 2a flows in from the flow path 15a opened in the inlet side end face 10a of the ceramic honeycomb filter 10 accommodated in the storage container 12, passes through the partition wall 11b as indicated by the arrow, and exits the exhaust gas on the outlet side. The gas 2b is exhausted from the flow path 15b opened in the outlet side end face 10b. When the inlet side exhaust gas 2a passes through the partition wall 11b, the particulates contained in the inlet side exhaust gas 2a are captured by the partition wall 11b, and the purified exhaust gas is released into the atmosphere as the outlet side exhaust gas 2b. . When the amount of the fine particles trapped in the partition wall 11b exceeds a certain amount, the filter is clogged. Therefore, the filter is regenerated by burning it with a burner or an electric heater.
しかしながら、フィルタを良好に再生するための最適な微粒子堆積量の範囲が狭く、最適範囲からはずれると、微粒子の自己発熱により、フィルタの溶融温度を超えてフィルタが溶損したり、或いは許容応力を超えてフィルタにクラックの発生することがあった。特にこの現象は、流路の流出側端部を閉塞する目封止部１ｂの上流付近で発生しやすかった。 However, the range of the optimum amount of fine particles deposited for good regeneration of the filter is narrow, and if it deviates from the optimum range, the filter may melt or exceed the allowable stress due to the self-heating of the fine particles. The filter sometimes cracked. In particular, this phenomenon was likely to occur in the vicinity of the upstream of the plugging portion 1b that blocks the outflow side end of the flow path.
このような現象が発生するのは、以下の理由による。フィルタ上に堆積した微粒子は、入口側端面で排ガス中の火花や点火ヒーターによって着火し、入口側端面で燃焼が広がり、それと同時に流路内を下流に向かって燃焼する。図１に示すように、セラミックハニカムフィルタ１０において、排ガス中の微粒子の一部は入口側端面１０ａに堆積し、大部分は流路１５内の入口排ガス通路１５ａの隔壁１１ｂに堆積する。ここで、入口側端面１０ａに堆積した微粒子に着火すると、入口側端面１０ａで燃焼が広がり、それと同時に入口排ガス通路１５ａの隔壁１１ｂに堆積した微粒子に伝播して流路１５内を下流に向かって、燃焼する。入口排ガス通路１５ａの隔壁１１ｂに堆積した微粒子が燃焼した上流側の隔壁では圧力損失が小さくなり、この部分の隔壁を通過して入口排ガス通路１５ａから出口側排ガス通路１５ｂに流れる排ガス量が増加し、下流側の隔壁を通過する排ガス量が減少する。燃焼が流路１５ａ内を下流に向かって伝播するに伴って、この傾向はさらに著しくなる。そこで、下流側の隔壁１１ｂに堆積した微粒子が燃焼する時には、上流側に比べて、同じ微粒子量が燃焼する間に通過する排ガス量が少ないので、排ガスによる冷却作用が少ない。その結果、下流側の隔壁１１ｂでは、上流側に比べて燃焼中の温度が高温になる。従って、入口側で、排ガスフィルタの再生に適した温度になるようにすると、出口側では燃焼温度が高温になり過ぎて、隔壁１１ｂの溶融、及び熱衝撃による破壊などの問題が生じていた。 Such a phenomenon occurs for the following reason. The fine particles deposited on the filter are ignited by sparks and ignition heaters in the exhaust gas at the inlet end face, and the combustion spreads at the inlet end face, and at the same time, burns downstream in the flow path. As shown in FIG. 1, in the ceramic honeycomb filter 10, some of the fine particles in the exhaust gas are deposited on the inlet side end face 10 a, and most of them are deposited on the partition wall 11 b of the inlet exhaust gas passage 15 a in the flow path 15. Here, when the particulates deposited on the inlet side end face 10a are ignited, combustion spreads on the inlet side end face 10a, and at the same time, propagates to the particulates deposited on the partition wall 11b of the inlet exhaust gas passage 15a and travels downstream in the flow path 15. To burn. The pressure loss is reduced in the upstream side partition where the particulates deposited on the partition wall 11b of the inlet exhaust gas passage 15a are burned, and the amount of exhaust gas flowing from the inlet exhaust gas passage 15a to the outlet side exhaust gas passage 15b through this part of the partition wall increases. The amount of exhaust gas passing through the downstream partition is reduced. This tendency becomes more pronounced as combustion propagates downstream in the flow path 15a. Therefore, when the fine particles deposited on the partition wall 11b on the downstream side are combusted, the amount of exhaust gas that passes while the same amount of fine particles is combusted is smaller than that on the upstream side, so that the cooling action by the exhaust gas is small. As a result, in the partition wall 11b on the downstream side, the temperature during combustion becomes higher than that on the upstream side. Therefore, if the temperature is suitable for the regeneration of the exhaust gas filter on the inlet side, the combustion temperature becomes too high on the outlet side, causing problems such as melting of the partition wall 11b and destruction due to thermal shock.
上記問題を解決するため、特許文献１に記載の発明には、ハニカム構造体のセル（流路）の各々において、排気ガス入口側の内径を、出口側の内径より大きくし、排ガス通路をテーパ状にした排ガスフィルタが開示されている。本排ガスフィルタによれば、流路がテーパ状になっていることから、下流側の流路の面積が上流側に比べて小さく、堆積する微粒子量も少なくなる。排ガス流量は上流側でも下流側でも変わらないため、下流側では、微粒子の燃焼により発生する熱量が少なく、排ガスによる冷却作用は変わらないので、結果として、下流側では上流側に比べて、燃焼温度の上昇を少なくすることができ、流路１５の下流側での過度の温度上昇を防ぎ、フィルタ全体に温度むらの少ない、均一な温度分布で燃焼させることができる。従って、排ガスフィルタの再生が容易になるとともに、過度の温度上昇によるクラックや溶融の問題をなくすことができるとしている。 In order to solve the above problem, in the invention described in Patent Document 1, in each cell (flow channel) of the honeycomb structure, the inner diameter on the exhaust gas inlet side is made larger than the inner diameter on the outlet side, and the exhaust gas passage is tapered. An exhaust gas filter is disclosed. According to this exhaust gas filter, since the flow path is tapered, the area of the flow path on the downstream side is smaller than that on the upstream side, and the amount of deposited fine particles is also reduced. Since the exhaust gas flow rate does not change on the upstream side or downstream side, the amount of heat generated by the combustion of fine particles is small on the downstream side, and the cooling action by the exhaust gas does not change.As a result, the combustion temperature on the downstream side is higher than that on the upstream side. Can be reduced, an excessive temperature rise on the downstream side of the flow path 15 can be prevented, and the entire filter can be burned with a uniform temperature distribution with little temperature unevenness. Therefore, the exhaust gas filter can be easily regenerated, and cracks and melting problems due to excessive temperature rise can be eliminated.
一方、排ガス通路をテーパ状にする技術として、特許文献２に記載の発明には、ハニカム構造体の複数のチャンネル（流路）の少なくとも一部は、少なくとも一方向の断面寸法が長さ方向に沿って減縮するチャンネル断面と、厚さが長さ方向に沿って減縮する隣接のチャンネル壁部分とを有するセルラハニカム体が開示されている。このセルラハニカム体によれば、従来の可塑化された粉末バッチ材料からハニカムを直接押し出すことによって作製可能なものより微細なセル構造と薄いセル壁（隔壁）を備えた製品を提供できるとしている。例えば、１６００セル／（１平方インチ）と０．１ｍｍ未満の隔壁厚さの隔壁構造が容易に得られるとしている。 On the other hand, as a technique for making the exhaust gas passage into a tapered shape, in the invention described in Patent Document 2, at least a part of the plurality of channels (flow passages) of the honeycomb structure has at least one cross-sectional dimension in the length direction. A cellular honeycomb body is disclosed having a channel cross-section that shrinks along and adjacent channel wall portions whose thickness shrinks along the length. According to this cellular honeycomb body, it is possible to provide a product having a finer cell structure and thinner cell walls (partition walls) than those which can be produced by directly extruding a honeycomb from a conventional plasticized powder batch material. For example, it is assumed that a partition structure having a partition wall thickness of 1600 cells / (1 square inch) and less than 0.1 mm can be easily obtained.
また、特許文献３には、多数の流路（通気孔）を有するハニカム体と、この流路の内面に向けて紫外線を照射する紫外線ランプを有してなり、ハニカム体の内面には紫外線の照射により励起される光励起化触媒物質が担持され、当該流路は空気の流れる方向に角度をもって配置される空気浄化装置が開示されている。この構成により、ハニカム体に形成された流路は空気の流れる方向に対して角度を持って構成されるため、空気流入口から空気流出口に向けて汚染空気が直進するのでなく、風路を曲げられた形で流過することになり、流路近辺で乱流が生じるとともに、流路近辺における汚染空気の滞留時間も長くなるので、紫外線照射を受ける時間を長くすることができるとしている。 Patent Document 3 includes a honeycomb body having a large number of flow paths (ventilation holes) and an ultraviolet lamp that irradiates ultraviolet rays toward the inner surface of the flow paths. An air purification device is disclosed in which a photoexcited catalytic material that is excited by irradiation is carried and the flow path is arranged at an angle in the direction of air flow. With this configuration, since the flow path formed in the honeycomb body is configured with an angle with respect to the air flow direction, the contaminated air does not travel straight from the air inflow port to the air outflow port. It flows in a bent shape, and turbulent flow is generated in the vicinity of the flow path, and the residence time of the contaminated air in the vicinity of the flow path is increased, so that the time for receiving ultraviolet irradiation can be increased.
しかしながら、上記従来技術の、流路の断面寸法を長さ方向に沿って減縮しテーパ状としたハニカム構造体や、流路を排気ガスの流入する方向に傾けたハニカム構造体を、例えばハニカムフィルタとして実際に使用してみると、以下のように、微粒子の不均一堆積による微粒子燃焼温度の局所的上昇が発生して、クラックや溶損が発生したり、金属容器内への収納に伴う不具合の発生する場合があった。 However, a honeycomb structure in which the cross-sectional dimension of the flow path is reduced and tapered along the length direction of the above-described prior art, or a honeycomb structure in which the flow path is inclined in the direction in which exhaust gas flows is used, for example, a honeycomb filter When actually used, as shown below, the particle combustion temperature locally rises due to non-uniform deposition of particles, causing cracks and erosion, and problems associated with storage in metal containers May occur.
特許文献１に記載の排ガスフィルタは、流路の入口側の内径を出口側の内径より大きくし、排ガス通路をテーパ状にしたハニカム構造体を使用しているが、本発明者らが実際にハニカムフィルタに採用してみると、流路に流入した排気ガスは流路入口からスムーズに浸入し、流路内を層流状態で直進し易く、排ガス中の微粒子は、流路の出口側端面を閉塞する目封止部１ｂの上流側端面に高濃度で堆積しやすくなり、ハニカムフィルタ内での微粒子の堆積に不均一が生じることがあった。このため、フィルタ再生の際に目封止部１ｂの上流側端面での微粒子の自己発熱に伴う温度上昇により、隔壁にクラックや溶損の発生することがあった。また、隔壁の表面粗さや気孔率については何ら考慮されていないこともあり、隔壁に沿って流れる排ガス中の微粒子は隔壁で効率良く捕集されない場合もあり、微粒子が流路の出口側端面を閉塞する目封止部１ｂの上流側端面に高濃度で堆積しやすいという問題点も有していた。また、特許文献１の第２図に記載されているように、排ガス通路をテーパ状とするのに伴い、外周壁もテーパ状となるため、ハニカム構造体の端面と外周壁により形成される交差部の少なくとも一部が鋭角を形成し、当該交差部がシャープエッジとなるため、金属容器への収納の際に破損したり、ハニカムフィルタとして使用した際の機械的振動や熱応力により鋭角交差部からクラックが発生し、場合によっては隔壁が脱落し、浄化不能になることもあるという問題も抱えていた。また、外周壁がテーパ状であることから、テーパを有さない内周面を持つ通常の金属容器への収納作業が難しいという問題点もあった。更に、ハニカム構造体は、セラミック原料を口金から押出すことにより一定断面形状を連続的に成形するという押出成形法で製造されることから、排ガス通路をテーパ状に製造することは困難であった。 The exhaust gas filter described in Patent Document 1 uses a honeycomb structure in which the inner diameter on the inlet side of the flow path is made larger than the inner diameter on the outlet side and the exhaust gas passage is tapered. When adopting a honeycomb filter, the exhaust gas flowing into the flow channel smoothly enters from the flow channel inlet and easily travels straight through the flow channel in a laminar flow state. It becomes easy to deposit at a high concentration on the upstream end face of the plugging portion 1b that closes the plug, and the deposition of fine particles in the honeycomb filter may be uneven. For this reason, when the filter is regenerated, cracks and erosion may occur in the partition wall due to a temperature rise accompanying self-heating of the fine particles on the upstream end face of the plugged portion 1b. In addition, the surface roughness and porosity of the partition wall may not be taken into consideration at all, and the fine particles in the exhaust gas flowing along the partition wall may not be efficiently collected by the partition wall, and the fine particles may be collected on the outlet side end surface of the flow path. There was also a problem that it was easy to deposit at a high concentration on the upstream end face of the plugging portion 1b to be closed. Further, as described in FIG. 2 of Patent Document 1, since the outer peripheral wall also becomes tapered as the exhaust gas passage is tapered, the intersection formed by the end face of the honeycomb structure and the outer peripheral wall. Since at least a part of the part forms an acute angle and the intersecting part becomes a sharp edge, it is damaged when stored in a metal container, or due to mechanical vibration or thermal stress when used as a honeycomb filter In other cases, there was a problem in that cracks occurred, and in some cases, the partition walls dropped off, making purification impossible. In addition, since the outer peripheral wall is tapered, there is a problem in that it is difficult to store in an ordinary metal container having an inner peripheral surface that does not have a taper. Furthermore, since the honeycomb structure is manufactured by an extrusion method in which a constant cross-sectional shape is continuously formed by extruding a ceramic raw material from a die, it is difficult to manufacture the exhaust gas passage in a tapered shape. .
また、特許文献２に記載のハニカム構造体については、流路の所望部位を目封止し、排ガス中の微粒子を隔壁で捕集することにより排ガスを浄化するハニカムフィルタに関する記載は一切なされていないが、従来技術に鑑み、流路の所望部位を目封止してハニカムフィルタとすると、流路の少なくとも一部の断面寸法が長さ方向に向かって減縮し、隔壁断面が長さ方向に沿って減縮しており、また、隔壁の表面粗さや気孔率については何ら考慮されていないことから、流路に流入した排ガスは流路入口からスムーズに浸入して隔壁での捕集が充分行われず、流路内を層流状態で直進し易くなるため、排ガス中の微粒子は、流路の流出側端部を閉塞する目封止部１ｂの上流側端面に高濃度で堆積しやすくなる。このため、ハニカムフィルタ内での微粒子の堆積に不均一が生じ、フィルタの再生の際に、微粒子の自己発熱に伴う温度上昇により、隔壁の溶損やクラック発生につながることが推定される。また、特許文献２のＦＩＧ．１で示されるように、端面と外周壁により形成される交差部の少なくとも一部が鋭角を形成し、当該交差部がシャープエッジとなるため、金属容器への収納の際に破損したり、ハニカムフィルタとして使用した際の機械的振動や熱応力により、鋭角交差部からクラックが発生し、場合によっては隔壁が脱落し、浄化不能になることもあるという問題も抱えていた。また、外周壁がテーパ状であることから、テーパを有さない内周面を持つ通常の金属容器への収納作業が難しいという問題点もあった。更に、ハニカム構造体は、セラミック原料を口金から押出すことにより一定断面形状を連続的に成形するという押出成形法で製造されることから、流路の断面を長さ方向に向かって減縮することは困難であった。 In addition, the honeycomb structure described in Patent Document 2 is not described at all about a honeycomb filter that purifies exhaust gas by plugging a desired portion of a flow path and collecting particulates in the exhaust gas by partition walls. However, in view of the prior art, when a desired portion of the flow path is plugged to form a honeycomb filter, the cross-sectional dimension of at least a part of the flow path is reduced in the length direction, and the partition wall cross section is along the length direction. In addition, since the surface roughness and porosity of the partition walls are not taken into consideration, exhaust gas that has flowed into the flow path smoothly enters from the flow path inlet and is not sufficiently collected by the partition walls. Since it is easy to go straight in the laminar flow state in the flow path, the particulates in the exhaust gas are likely to accumulate at a high concentration on the upstream end face of the plugging portion 1b that closes the outflow side end of the flow path. For this reason, it is presumed that the accumulation of fine particles in the honeycomb filter is non-uniform, and that when the filter is regenerated, the temperature rises due to the self-heating of the fine particles, leading to melting of the partition walls and cracks. Further, FIG. 1, at least part of the intersection formed by the end face and the outer peripheral wall forms an acute angle, and the intersection becomes a sharp edge. Due to mechanical vibration and thermal stress when used as a filter, there was a problem that cracks were generated from the acute intersections, and in some cases, the partition walls dropped out, making it impossible to purify. In addition, since the outer peripheral wall is tapered, there is a problem in that it is difficult to store in an ordinary metal container having an inner peripheral surface that does not have a taper. Furthermore, since the honeycomb structure is manufactured by an extrusion molding method in which a ceramic raw material is extruded from a die and a constant cross-sectional shape is continuously formed, the cross section of the flow path is reduced in the length direction. Was difficult.
また、特許文献３に記載の空気浄化装置では、ハニカム構造体を空気の流れる方向に対してハニカム体全体が傾くように配置しているが、特許文献３の図２及び図５に示されるように、ハニカム体が傾くことによって、余分なスペースの必要になる。仮に、本発明の主な利用分野である、自動車等の排気ガス浄化装置に適用しようとした場合、自動車等の取り付けスペースは限定されることから、取り付けが困難になるといった問題や、排気経路を傾けた特別の金属容器が必要になるといった問題につながることがあった。一方、特許文献３に記載の発明には、通気孔（流路）がハニカム体の中で角度をもって形成されていても良く、この場合浄化ユニットの底板に対して略直角にハニカム体を挿入すれば足りるとの記載があるが、流路をハニカム体の中で傾ける方法の具体的記載がないため、製造技術の高度化により、複雑形状を高精度で得ているセラミックハニカム構造体に対しては、外周壁に対して流路（隔壁）を傾けることは、困難であるとういう問題点があった。また、隔壁の表面粗さや気孔率については何ら考慮されていないことから、従来技術に鑑み、流路の所望部位を目封止してハニカムフィルタとして使用した場合、流路に流入した排気ガスは流路入口からスムーズに浸入して、隔壁での捕集が充分行われず、流路内を層流状態で直進し易くなるため、排気ガス中の微粒子は、流路の流出側端部を閉塞する目封止部１ｂの上流側端面に高濃度で堆積しやすくなる。このため、ハニカムフィルタ内での微粒子の堆積に不均一が生じ、フィルタ再生の際に、微粒子の自己発熱に伴う温度上昇により、隔壁の溶損やクラック発生につながるという問題点があった。 Further, in the air purification device described in Patent Document 3, the honeycomb structure is arranged so that the whole honeycomb body is inclined with respect to the air flow direction, as shown in FIGS. 2 and 5 of Patent Document 3. In addition, when the honeycomb body is inclined, an extra space is required. If an attempt is made to apply the present invention to an exhaust gas purifying apparatus such as an automobile, the space for attaching the automobile or the like is limited. This could lead to problems such as the need for a special tilted metal container. On the other hand, in the invention described in Patent Document 3, the air holes (flow paths) may be formed at an angle in the honeycomb body. In this case, the honeycomb body is inserted at a substantially right angle with respect to the bottom plate of the purification unit. Although there is a description that it is sufficient, since there is no specific description of the method of tilting the flow path in the honeycomb body, the ceramic honeycomb structure that has obtained a complicated shape with high precision by the advancement of manufacturing technology However, there is a problem that it is difficult to incline the flow path (partition wall) with respect to the outer peripheral wall. In addition, since the surface roughness and porosity of the partition walls are not taken into consideration, in view of the prior art, when a desired part of the flow path is plugged and used as a honeycomb filter, the exhaust gas flowing into the flow path is Since it penetrates smoothly from the inlet of the flow path and is not collected sufficiently by the partition walls, it becomes easy to go straight in the flow path in a laminar flow state, so particulates in the exhaust gas block the outlet side end of the flow path It becomes easy to deposit at a high concentration on the upstream end face of the plugged portion 1b. For this reason, non-uniform deposition of the fine particles in the honeycomb filter occurs, and there is a problem that the temperature rise accompanying self-heating of the fine particles during filter regeneration leads to melting of the partition walls and generation of cracks.
本発明の目的は、例えばハニカムフィルタ内における微粒子の不均一堆積の問題を解消し、再生(燃焼)を行う際に部分的な温度上昇を発生しにくくして、溶損や破損に至ることを防止し、且つ金属容器への収納時の取り扱いや、使用時の機械振動、機械的衝撃や熱衝撃にも耐え、長期間に亘り使用できるセラミックハニカム構造体を提供することを目的とする。 An object of the present invention is to solve the problem of non-uniform deposition of fine particles in a honeycomb filter, for example, and to prevent partial temperature rise during regeneration (combustion), resulting in melting and breakage. It is an object of the present invention to provide a ceramic honeycomb structure that can be used for a long period of time and can withstand handling during storage in a metal container, mechanical vibration during use, mechanical shock, and thermal shock.
上記問題を解決するため、本発明者等は、外周壁とこの外周壁の内側で隔壁により囲まれた流路を有する多孔質セラミックハニカム構造体の、排気ガスの流れ方向に対するハニカムフィルタの外形形状、及び隔壁の配置について、鋭意検討を行った結果、これらを最適な範囲に調整することによって、例えば排気ガス中の微粒子をハニカム構造体内で比較的均等に堆積させることができ、従来技術で問題となっていた再生時における局所的過度な温度上昇による溶損やクラック発生の問題や、金属容器への収納時の不具合、使用時の機械的衝撃や熱衝撃による破損の問題が起こりにくくなることを見出し本発明に想到した。 In order to solve the above problems, the present inventors have developed an outer shape of a honeycomb filter with respect to a flow direction of exhaust gas in a porous ceramic honeycomb structure having a peripheral wall and a channel surrounded by a partition wall inside the peripheral wall. As a result of intensive investigations on the arrangement of the partition walls, and adjusting these to the optimum range, for example, fine particles in the exhaust gas can be deposited relatively evenly in the honeycomb structure, which is a problem with the prior art. The problem of melting and cracking due to excessive local temperature rise during regeneration, defects during storage in metal containers, and mechanical and thermal shock damage during use are less likely to occur. And the present invention has been conceived.
すなわち、本発明に係るセラミックハニカム構造体は、外周壁とこの外周壁の内側で隔壁により囲まれた流路を有する多孔質セラミックハニカム構造体であって、該セラミックハニカム構造体の端面と外周壁が略直交し、該外周壁が略円筒形状であり、前記隔壁の表面粗さが最大高さＲyで１０μｍ以上であり、且つ長手方向断面において隣り合う隔壁が略平行であると共に外周壁に対して少なくとも一部の隔壁が傾いていることを特徴とする。 That is, the ceramic honeycomb structure according to the present invention is a porous ceramic honeycomb structure having a peripheral wall and a flow path surrounded by a partition wall inside the peripheral wall, and the end face and the peripheral wall of the ceramic honeycomb structure Are substantially perpendicular to each other, the outer peripheral wall has a substantially cylindrical shape, the surface roughness of the partition wall is 10 μm or more at the maximum height Ry, and adjacent partition walls in the longitudinal section are substantially parallel to the outer wall. And at least some of the partition walls are inclined.
本発明のセラミックハニカム構造体は、前記隔壁の気孔率が５０〜８０％であって、前記流路の所望部位が目封止され、フィルタとして使用されることが好ましい。 In the ceramic honeycomb structure of the present invention, it is preferable that the partition wall has a porosity of 50 to 80%, and a desired portion of the flow path is plugged and used as a filter.
本発明のセラミックハニカム構造体の隔壁に沿って切断した２等分割断面において、隔壁の長手方向端部が外周壁と接する隔壁を１〜６ケ有することが好ましい。 In the two equally divided sections cut along the partition walls of the ceramic honeycomb structure of the present invention, it is preferable that the longitudinal ends of the partition walls have 1 to 6 partition walls in contact with the outer peripheral wall.
また、本発明のセラミックハニカム構造体の隔壁に沿って切断した２等分割断面において、前記外周壁に対して少なくとも一部の隔壁が０．３〜３．３°傾いていることが好ましい。 In addition, in a bisection section cut along the partition walls of the ceramic honeycomb structure of the present invention, it is preferable that at least some partition walls are inclined by 0.3 to 3.3 ° with respect to the outer peripheral wall.
本発明のセラミックハニカム構造体において、前記セラミックハニカム構造体の隔壁及び／または目封止部の少なくとも一部に触媒物質が担持されていることが好ましい。 In the ceramic honeycomb structure of the present invention, it is preferable that a catalyst substance is supported on at least a part of the partition walls and / or the plugging portions of the ceramic honeycomb structure.
本発明のセラミックハニカム構造体において、最外周に位置する流路が外部との間の隔壁を有しないことによって外部に開口して概略軸方向に延びる凹溝を形成しているセラミックハニカム本体の、前記凹溝を充填して外表面を形成する外周壁が形成されており、外周壁を構成する部材と凹溝の間の少なくとも一部に空隙を有していることが好ましい。 In the ceramic honeycomb structure of the present invention, the flow path located on the outermost periphery does not have a partition wall between the outside, so that the outside of the ceramic honeycomb body that opens to the outside and extends in the substantially axial direction is formed. It is preferable that an outer peripheral wall that fills the concave groove to form an outer surface is formed, and that at least part of the gap between the member constituting the outer peripheral wall and the concave groove is provided.
本発明のセラミックハニカム構造体において、前記外周壁を構成する部材と凹溝の間に形成された空隙を有する凹溝の個数割合が全凹溝のうちの５％以上であることが好ましい。 In the ceramic honeycomb structure of the present invention, it is preferable that a ratio of the number of concave grooves having voids formed between the members constituting the outer peripheral wall and the concave grooves is 5% or more of all the concave grooves.
本発明のセラミックハニカム構造体において、最外周に位置する流路が外部との間の隔壁を有しないことによって外部に開口して概略軸方向に延びる凹溝を形成しているセラミックハニカム本体の、前記凹溝を充填して外表面を形成する外周壁が形成されており、外周壁の少なくとも一部に外表面に開口した空隙を有していることが好ましい。 In the ceramic honeycomb structure of the present invention, the flow path located on the outermost periphery does not have a partition wall between the outside, so that the outside of the ceramic honeycomb body that opens to the outside and extends in the substantially axial direction is formed. It is preferable that an outer peripheral wall filling the concave groove to form an outer surface is formed, and at least a part of the outer peripheral wall has a gap opened to the outer surface.
本発明のセラミックハニカム構造体において、前記外表面に開口した空隙の長さの合計がセラミックハニカム構造体全長の１倍以上であることが好ましい。 In the ceramic honeycomb structure of the present invention, it is preferable that the total length of the voids opened in the outer surface is one or more times the total length of the ceramic honeycomb structure.
次に、本発明の各構成の理由を説明する。
本発明のセラミックハニカム構造体について、図３のセラミックハニカムフィルタの隔壁に沿って切断した２等分割断面模式図を用いて説明する。本発明のセラミックハニカム構造体は、端面と外周壁が略直交し、該外周壁が略円筒形状であり、前記隔壁１１ｂの表面粗さが最大高さＲyで１０μｍ以上あり、且つ長手方向断面において隣り合う隔壁１１ｂが略平行であると共に外周壁１１ａに対して少なくとも一部の隔壁１１ｂが傾いている。このため、ハニカム構造体の隔壁がハニカム構造体の外周壁と平行の場合、或いは流路がテーパ状になっている場合に比べて、例えば流路に流入した微粒子を含む排気ガス２ａは、排気ガスの流入方向に対して傾いた隔壁でその方向を曲げられ、流路内の排気ガスの流れに乱れが生じるため、表面粗さが最大高さＲyで１０μｍ以上を有する隔壁が、排気ガス中に存在する微粒子を入口側から出口側に亘って捕集し易くなる。このため、排気ガス流出側端部の目封止部付近に微粒子が集中的に堆積することを防止し、ハニカムフィルタ全体、特にハニカムフィルタの長手方向に亘って略均一に微粒子を分散させることが出来るので、フィルタ再生を行う際の微粒子の部分的な堆積箇所での急激な温度上昇を抑えることができ、再生を容易に行うことができる。
Next, the reason of each structure of this invention is demonstrated.
The ceramic honeycomb structure of the present invention will be described using a schematic diagram of two equally divided sections cut along the partition walls of the ceramic honeycomb filter of FIG. In the ceramic honeycomb structure of the present invention, the end face and the outer peripheral wall are substantially orthogonal, the outer peripheral wall is substantially cylindrical, the surface roughness of the partition wall 11b is 10 μm or more at the maximum height Ry, and in the longitudinal section. Adjacent partition walls 11b are substantially parallel, and at least some of the partition walls 11b are inclined with respect to the outer peripheral wall 11a. For this reason, compared with the case where the partition walls of the honeycomb structure are parallel to the outer peripheral wall of the honeycomb structure or the flow path is tapered, for example, the exhaust gas 2a containing fine particles flowing into the flow path Since the direction is bent by the partition wall inclined with respect to the gas inflow direction and the flow of the exhaust gas in the flow path is disturbed, the partition wall having a surface roughness of 10 μm or more at the maximum height Ry is in the exhaust gas. It becomes easy to collect the fine particles present in the gas from the inlet side to the outlet side. For this reason, it is possible to prevent fine particles from being concentrated in the vicinity of the plugging portion at the end portion on the exhaust gas outflow side, and to disperse the fine particles substantially uniformly over the entire honeycomb filter, particularly in the longitudinal direction of the honeycomb filter. As a result, it is possible to suppress an abrupt temperature rise at the part where the fine particles are partially deposited during filter regeneration, and the regeneration can be performed easily.
また、本発明のセラミックハニカム構造体は、該ハニカム構造体端面と外周壁が略直交し、該外周壁が略円筒形状であるため、ハニカム構造体の外周壁と端面の交差部が略直角となって、特許文献１及び２の発明に記載されたハニカム構造体のような鋭角部は形成されないことから、金属容器への収納の際に破損することがなく、ハニカムフィルタとして使用された際の機械的振動や熱応力による破損を防ぐことができるのと共に、特許文献１及び２の発明に記載されたハニカム構造体のように外周がテーパ状になっていないため、金属容器内への収納も容易に行える。尚、セラミックハニカム構造体の外周壁と端面の交差部には大きさ０．５〜３ｍｍ程度のＲまたは面取りを施すと、より破損しにくくなるのでより好ましい。ここで、外周壁に対して隔壁を傾けるのは、全ての隔壁で行う必要はなく、一部の隔壁もしくは隔壁の長手方向の一部でも構わない。また、その傾きの角度はハニカム構造体全域に亘って一定である必要もなく、ハニカム構造体内の位置によって変わっても構わない。 Further, in the ceramic honeycomb structure of the present invention, the end face of the honeycomb structure and the outer peripheral wall are substantially orthogonal, and the outer peripheral wall has a substantially cylindrical shape, so that the intersection between the outer peripheral wall and the end face of the honeycomb structure is substantially perpendicular. Thus, since an acute angle portion like the honeycomb structure described in the inventions of Patent Documents 1 and 2 is not formed, it is not damaged when stored in a metal container, and when used as a honeycomb filter. In addition to preventing damage due to mechanical vibration and thermal stress, the outer periphery is not tapered as in the honeycomb structures described in the inventions of Patent Documents 1 and 2, so that they can be stored in a metal container. Easy to do. In addition, it is more preferable to apply R or chamfering of a size of about 0.5 to 3 mm to the intersection between the outer peripheral wall and the end face of the ceramic honeycomb structure because it is more difficult to break. Here, it is not necessary to incline the partition walls with respect to the outer peripheral wall, but it is not necessary to perform the operation for all the partition walls, and may be a part of the partition walls or a part of the partition walls in the longitudinal direction. Further, the inclination angle does not have to be constant over the entire honeycomb structure, and may vary depending on the position in the honeycomb structure.
ここで、長手方向断面において隣り合う隔壁１１ｂが略平行であるとは、一つの流路を形成する隣接する隔壁の間隔が、略一定で有ることをいい、流路の入り口から出口にわたって、（隔壁間隔の平均値）×（±０．２）内であることを言う。また、端面と外周壁が略直交しているとは、一方の端面に幾何学的に直角な曲面に対して、他方の端面のずれ量が（全長）×｛±ｔａｎ（０．３°）｝内であることを言い、外周壁が略円筒形状であるとは、両端面から１２．７ｍｍの位置で等間隔で各４ケ所測定した外径寸法が（合計８ケ所）、（外径寸法の平均値）×（±０．０１）内であることを言う。 Here, the adjacent partition walls 11b in the longitudinal cross section being substantially parallel means that the interval between the adjacent partition walls forming one flow path is substantially constant. From the entrance to the exit of the flow path, Mean value of partition wall spacing) × (± 0.2). Further, the fact that the end face and the outer peripheral wall are substantially orthogonal to each other means that the shift amount of the other end face is (total length) × {± tan (0.3 °) with respect to a curved surface geometrically perpendicular to one end face. }, And that the outer peripheral wall has a substantially cylindrical shape means that the outer diameter dimensions measured at four locations at equal intervals at positions of 12.7 mm from both end faces (total of eight positions), (outer diameter dimension) Mean value) × (± 0.01).
ここで、本発明のハニカム構造体において、隔壁の表面粗さを最大高さＲyで１０μｍ以上とするのは、隔壁の表面粗さが最大高さＲyで１０μｍ以上の場合には、隔壁表面に形成された凹凸部により、例えば排気ガス中の微粒子を効率良く捕集することが可能となるからである。隔壁の表面粗さのより好ましい範囲は、最大高さＲyで２０〜１００μｍである。尚、最大高さＲyは、表面粗さ計により、隔壁表面形状を長手方向に測定し、
ＪＩＳ Ｂ ０６０１−１９９４に準じて求めたものである。
Here, in the honeycomb structure of the present invention, the partition wall surface roughness is 10 μm or more at the maximum height Ry when the partition wall surface roughness is 10 μm or more at the maximum height Ry. This is because, for example, fine particles in the exhaust gas can be efficiently collected by the formed uneven portion. A more preferable range of the surface roughness of the partition walls is 20 to 100 μm at the maximum height Ry. The maximum height Ry is measured by measuring the surface shape of the partition wall in the longitudinal direction with a surface roughness meter.
It is determined according to JIS B 0601-1994.
本発明のセラミックハニカム構造体において、前記隔壁の気孔率が５０〜８０％であって、前記流路の所望部位が目封止され、フィルタとして使用されることが好ましいのは、前記隔壁１１ｂの気孔率が５０〜８０％であると、例えば排気ガス中の微粒子を捕集し易いのと共に、前記流路の所望部位が目封止されたフィルタとして使用した場合にフィルタの圧力損失が上昇するのを防ぎ、エンジンの出力低下を防ぐためである。このため、排気ガス流出側端部の目封止部付近に微粒子が集中的に堆積することを防止し、ハニカムフィルタ全体、特にハニカムフィルタの長手方向に亘って略均一に微粒子を堆積させることが出来るので、圧力損失の上昇を防ぐと共に、フィルタ再生を行う際の微粒子の部分的な堆積箇所での急激な温度上昇を抑えることができ、再生を容易に行うことができる。 In the ceramic honeycomb structure of the present invention, it is preferable that the partition wall has a porosity of 50 to 80%, and a desired portion of the flow path is plugged and used as a filter. When the porosity is 50 to 80%, for example, particulates in the exhaust gas are easily collected, and the pressure loss of the filter increases when the desired portion of the flow path is used as a plugged filter. This is to prevent the engine output from decreasing. Therefore, it is possible to prevent the fine particles from being concentrated in the vicinity of the plugging portion at the exhaust gas outflow side end, and to deposit the fine particles substantially uniformly over the entire honeycomb filter, particularly the longitudinal direction of the honeycomb filter. As a result, it is possible to prevent the pressure loss from increasing and to suppress the rapid temperature increase at the part of the fine particles when the filter is regenerated, thereby facilitating the regeneration.
この理由は、本発明のセラミックハニカム構造体において、隔壁の気孔率が５０％未満の場合には、隔壁自体の排気ガスの透過性が低下し、排気ガス出口側の目封止部に微粒子が高濃度に堆積しやすくなるのと共に、ハニカム構造体の圧力損失が高くなるからである。一方、気孔率が８０％を超えると微粒子の捕集効率が低下するのとともに、ハニカム構造体の強度が低下するからである。この気孔率のより好ましい範囲は６０〜７５％である。 The reason for this is that in the ceramic honeycomb structure of the present invention, when the porosity of the partition walls is less than 50%, the exhaust gas permeability of the partition walls themselves decreases, and fine particles are present in the plugging portion on the exhaust gas outlet side. This is because it becomes easy to deposit at a high concentration and the pressure loss of the honeycomb structure increases. On the other hand, when the porosity exceeds 80%, the collection efficiency of the fine particles decreases, and the strength of the honeycomb structure decreases. A more preferable range of the porosity is 60 to 75%.
本発明のセラミックハニカム構造体の隔壁に沿って切断した２等分割断面において、隔壁の長手方向端部が外周壁と接する隔壁を１〜６ケ有することが好ましいのは、上述したように、隔壁の表面粗さをＲｙ１０μｍ以上とし、且つ長手方向断面において外周壁に対して少なくとも一部の隔壁を傾かせていると、排気ガス中に存在する微粒子を入口側から出口側に亘る隔壁で捕集し易くなるが、その傾きには好適な範囲があるからである。 In the bisected cross section cut along the partition walls of the ceramic honeycomb structure of the present invention, it is preferable that the partition walls have 1 to 6 partition walls whose longitudinal ends are in contact with the outer peripheral wall as described above. When the surface roughness of Ry is 10 μm or more and at least a part of the partition wall is inclined with respect to the outer peripheral wall in the longitudinal section, the particulates present in the exhaust gas are collected by the partition wall from the inlet side to the outlet side. This is because the inclination has a suitable range.
ここで、外周壁に対する隔壁の傾きの大きさについて、図２〜図４を用いて説明する。図２は、本発明のセラミックハニカム構造体で形成されたセラミックハニカムフィルタの流路入口側から見た端面を示す模式図である。図３は、前述のように外周壁と隔壁が傾きをなすように形成されたセラミックハニカム構造体で作製されたセラミックハニカムフィルタの隔壁に沿って切断した２等分割断面の模式断面図の一例を示したものであるが、外周近傍の隔壁端部１１ｂ−ｔが外周壁で接するように形成されている。ここで、隔壁に沿って切断した２等分割断面とは、セラミックハニカム構造体を長手方向に凡そ同一の大きさに２分割する際に、隔壁に沿うように切断した面のことをいい、図４に切断の箇所１７を示す。図３の例では隔壁の長手方向端部が外周壁と接する隔壁は１ヶである。このセラミックハニカム構造体の外周壁は段落（００３９）に記載するように外部に開口して軸方向に延びる凹溝を形成しているセラミックハニカム本体の凹溝に外周壁を構成する部材を充填して形成されるものであるが、図４は、本発明のセラミックハニカム構造体において、外周壁が形成される前のセラミックハニカム本体の外観模式図を示している。但し、この模式図では外部に開口して軸方向に延びる凹溝の記載は省略している。このセラミックハニカム本体に外周壁を形成すると、外周壁と隔壁の端部１１ｂ−ｔが接するように形成されることが認識される。従って、セラミックハニカム構造体の隔壁に沿って切断した２等分割断面において、隔壁の長手方向端部が外周壁と接する隔壁の数と、外周壁に対する隔壁の傾きは相関があり、隔壁の長手方向端部が外周壁と接する隔壁の数を１〜６ヶと規定することにより、外周壁に対する隔壁の傾きの範囲を規定することができるのである。 Here, the magnitude | size of the inclination of the partition with respect to an outer peripheral wall is demonstrated using FIGS. FIG. 2 is a schematic view showing an end face of the ceramic honeycomb filter formed of the ceramic honeycomb structure of the present invention as viewed from the flow path inlet side. FIG. 3 is an example of a schematic sectional view of a bisection section cut along a partition wall of a ceramic honeycomb filter made of a ceramic honeycomb structure formed so that the outer peripheral wall and the partition wall are inclined as described above. As shown, the partition wall end 11b-t in the vicinity of the outer periphery is formed so as to be in contact with the outer peripheral wall. Here, the bisected cross section cut along the partition wall means a surface cut along the partition wall when the ceramic honeycomb structure is divided into two parts of approximately the same size in the longitudinal direction. 4 shows a cut portion 17. In the example of FIG. 3, there is one partition wall where the longitudinal end of the partition wall is in contact with the outer peripheral wall. As described in the paragraph (0039), the outer peripheral wall of the ceramic honeycomb structure is opened to the outside to form a concave groove extending in the axial direction. The concave groove of the ceramic honeycomb body is filled with a member constituting the outer peripheral wall. FIG. 4 is a schematic external view of the ceramic honeycomb body before the outer peripheral wall is formed in the ceramic honeycomb structure of the present invention. However, in this schematic diagram, the description of the groove that opens to the outside and extends in the axial direction is omitted. It is recognized that when the outer peripheral wall is formed on the ceramic honeycomb body, the outer peripheral wall and the end portions 11b-t of the partition wall are formed in contact with each other. Therefore, in a bisection section cut along the partition walls of the ceramic honeycomb structure, the number of partition walls in which the longitudinal ends of the partition walls are in contact with the outer peripheral wall is correlated with the inclination of the partition walls with respect to the outer peripheral wall. By defining the number of partition walls whose end portions are in contact with the outer peripheral wall as 1 to 6, the range of the inclination of the partition walls with respect to the outer peripheral wall can be defined.
本発明のセラミックハニカム構造体の隔壁に沿って切断した２等分割断面において、隔壁の長手方向端部が外周壁と接する隔壁の数を１〜６ヶ有することが好ましいとするのは、以下の理由による。セラミックハニカム構造体において、隔壁の長手方向端部が外周壁と接する隔壁が１ケ未満であると、外周壁に対する隔壁の傾きが小さく、流路内での排気ガスの流れに乱れを生じさせにくいため、例えば微粒子が排気ガス出口側目封止部付近へ高濃度で堆積するのを防ぐ効果が小さくなることもあるからである。また、セラミックハニカム構造体の長手方向端部が外周壁と接する隔壁が６ケを超えるようにすると、入口側から出口側に貫通しない流路の割合が増え、例えばセラミックハニカムフィルタの場合、実質的にフィルタ面積が小さくなることから、圧力損失が上昇することもあるからである。なお、セラミックハニカム構造体の隔壁に沿って切断した２等分割断面において、長手方向端部が外周壁と接する隔壁を１〜４ケ有すると、上記観点から尚好ましい。 In the two equally divided sections cut along the partition walls of the ceramic honeycomb structure of the present invention, it is preferable that the longitudinal ends of the partition walls have 1 to 6 partition walls in contact with the outer peripheral wall. Depending on the reason. In the ceramic honeycomb structure, when the number of partition walls whose longitudinal ends are in contact with the outer peripheral wall is less than one, the inclination of the partition wall with respect to the outer peripheral wall is small, and the flow of exhaust gas in the flow path is hardly disturbed. Therefore, for example, the effect of preventing the fine particles from being deposited at a high concentration near the exhaust gas outlet side plugged portion may be reduced. Further, if the number of partition walls where the longitudinal end of the ceramic honeycomb structure is in contact with the outer peripheral wall exceeds six, the proportion of the channels that do not penetrate from the inlet side to the outlet side increases. For example, in the case of a ceramic honeycomb filter, This is because the pressure loss may increase because the filter area becomes smaller. In addition, in the bisection section cut along the partition walls of the ceramic honeycomb structure, it is more preferable from the above viewpoint that the longitudinal end portion has 1 to 4 partition walls in contact with the outer peripheral wall.
セラミックハニカム構造体の隔壁に沿って切断した２等分割断面において外周壁に対して少なくとも一部の隔壁が傾いている、別の例を、図５〜８を用いて説明する。図５はセラミックハニカム構造体の隔壁に沿って切断した２等分割断面の模式断面図の一例を示したものであり、外周近傍の隔壁端部が２ケ所で外周壁と接するように形成される。図６は、図５のセラミックハニカム構造体において、外周壁を形成する前のセラミックハニカム本体の外観模式図を示したものであり、隔壁に沿って切断した２等分割断面において、隔壁の長手方向端部が外周壁と接する隔壁の数が２ケであることが認識される。図６の外観模式図においても、外部に開口して軸方向に延びる凹溝の記載は省略している。 Another example in which at least a part of the partition walls is inclined with respect to the outer peripheral wall in a bisection section cut along the partition walls of the ceramic honeycomb structure will be described with reference to FIGS. FIG. 5 shows an example of a schematic cross-sectional view of a bisection section cut along the partition walls of the ceramic honeycomb structure, and is formed so that the partition wall end portions in the vicinity of the outer periphery are in contact with the outer peripheral wall at two locations. . FIG. 6 is a schematic external view of the ceramic honeycomb body before the outer peripheral wall is formed in the ceramic honeycomb structure of FIG. 5, and the longitudinal direction of the partition wall in a bisection section cut along the partition wall. It is recognized that the number of partition walls whose end portions are in contact with the outer peripheral wall is two. Also in the schematic external view of FIG. 6, the description of the groove that opens to the outside and extends in the axial direction is omitted.
図７は、セラミックハニカム構造体の隔壁に沿って切断した２等分割断面の模式断面図の一例を示したものであり、隔壁の傾きが長手方向で変化しており、外周近傍の隔壁端部が２ケ所で外周壁と接するように形成されたものである。図８は、図７のセラミックハニカム構造体において、外周壁を形成する前のセラミックハニカム本体の外観模式図を示したものであり、隔壁に沿って切断した２等分割断面において、隔壁の長手方向端部が外周壁と２ケ所で接しているが、外周壁と接する隔壁の数は１ケに相当することが認識される。図８の外観模式図においても、外部に開口して軸方向に延びる凹溝の記載は省略している。 FIG. 7 shows an example of a schematic cross-sectional view of a bisection section cut along a partition wall of a ceramic honeycomb structure, where the partition wall inclination changes in the longitudinal direction, and the partition wall end near the outer periphery Is formed so as to be in contact with the outer peripheral wall at two places. FIG. 8 is a schematic external view of the ceramic honeycomb body before the outer peripheral wall is formed in the ceramic honeycomb structure of FIG. 7. In the bisection section cut along the partition walls, the longitudinal direction of the partition walls is shown. Although the end portion is in contact with the outer peripheral wall at two locations, it is recognized that the number of partition walls in contact with the outer peripheral wall corresponds to one. Also in the schematic external view of FIG. 8, the description of the groove that opens to the outside and extends in the axial direction is omitted.
前記ハニカム構造体の隔壁に沿って切断した２等分割断面において、外周壁に対して少なくとも一部の隔壁が０．３〜３．３°傾いているとより好ましいのは、上記同様、外周壁と隔壁の傾きには最適な範囲があるからである。即ち、前記ハニカム構造体の隔壁に沿って切断した２等分割断面において、外周壁に対して少なくとも一部の隔壁が０．３°未満で傾いていると、例えば微粒子が排気ガス出口側目封止部付近へ高濃度で堆積するのを防ぐ効果が小さくなることもあるからであり、３．３°を超えて傾いていると、入口側から出口側に貫通しない流路の割合が増え、例えばセラミックハニカムフィルタの場合、実質的にフィルタ面積が小さくなることから、圧力損失が上昇することもあるからである。なお、前記ハニカム構造体の長手方向断面において、外周壁に対して少なくとも一部の隔壁が０．５〜２°傾いていると、上記観点から更に好ましい。 More preferably, in the bisection section cut along the partition walls of the honeycomb structure, it is more preferable that at least a part of the partition walls is inclined by 0.3 to 3.3 ° with respect to the outer periphery wall, as described above. This is because there is an optimum range for the inclination of the partition wall. That is, in a bisection section cut along the partition wall of the honeycomb structure, if at least a part of the partition wall is inclined with respect to the outer peripheral wall at an angle of less than 0.3 °, for example, fine particles are sealed on the exhaust gas outlet side. This is because the effect of preventing the deposition at a high concentration near the stop portion may be reduced. If the inclination is more than 3.3 °, the proportion of the flow path that does not penetrate from the inlet side to the outlet side increases. This is because, for example, in the case of a ceramic honeycomb filter, the pressure loss may increase because the filter area is substantially reduced. In the longitudinal section of the honeycomb structure, it is more preferable from the above viewpoint that at least a part of the partition walls is inclined by 0.5 to 2 ° with respect to the outer peripheral wall.
本発明のセラミックハニカム構造体において、前記セラミックハニカム構造体の隔壁及び／または目封止部の少なくとも一部に触媒物質が担持されていることが好ましい理由は、排気ガス流入方向に対して傾いた隔壁表面に担持された触媒物質の作用により、より隔壁での微粒子の捕集、浄化が行われ易くなるため、排気ガス出口側端面の目封止部付近に微粒子が集中的に堆積することを防止し易くなるからである。ここで触媒物質は、白金族金属を含む酸化触媒や微粒子燃焼触媒であると好ましい。尚、白金族金属を含む酸化触媒は、たとえば、Ｐｔ、Ｐｄ、Ｒｕ、Ｒｈ又はその組合せ、白金族金属酸化物等が含まれるが、アルカリ土類金属酸化物や希土類酸化物等を含んでも良い。また、白金族金属を含む触媒物質には、公知のγアルミナ等の活性アルミナからなる高比表面積材料が含まれると、白金族金属等と排気ガスとの接触面積を大きくすることができ、排気ガスの浄化効率を高めることができることから好ましい。また、微粒子燃焼触媒としては、ベース金属触媒、典型的にはランタン、セシウム、バナジウム（Ｌａ／Ｃｓ／Ｖ２Ｏ３）類よりなる触媒物質であると好ましい。 In the ceramic honeycomb structure of the present invention, the reason why the catalytic substance is preferably supported on at least a part of the partition walls and / or the plugging portions of the ceramic honeycomb structure is inclined with respect to the exhaust gas inflow direction. The action of the catalyst substance supported on the partition wall surface makes it easier to collect and purify the particulates in the partition wall, so that the particulates are concentrated in the vicinity of the plugging portion on the exhaust gas outlet side end surface. It is because it becomes easy to prevent. Here, the catalyst material is preferably an oxidation catalyst or a particulate combustion catalyst containing a platinum group metal. The oxidation catalyst containing a platinum group metal includes, for example, Pt, Pd, Ru, Rh or a combination thereof, a platinum group metal oxide, etc., but may contain an alkaline earth metal oxide, a rare earth oxide, or the like. . Further, if the catalyst material containing platinum group metal contains a high specific surface area material made of active alumina such as known γ alumina, the contact area between the platinum group metal etc. and the exhaust gas can be increased, This is preferable because the gas purification efficiency can be increased. The fine particle combustion catalyst is preferably a base metal catalyst, typically a catalyst material composed of lanthanum, cesium, vanadium (La / Cs / V 2 O 3 ).
本発明のセラミックハニカム構造体において、最外周に位置する流路が外部との間の隔壁を有しないことによって外部に開口して概略軸方向に延びる凹溝を形成しているセラミックハニカム本体の、前記凹溝を充填して外表面を形成する外周壁が形成されており、外周壁を構成する部材と凹溝の間の少なくとも一部に空隙を有していることが好ましいのは、以下の理由による。本発明の構成である外周壁と隔壁が傾きをなし、かつハニカム構造体端面と外周壁が略直交するようにするには、公知技術（例えば特許文献４及び５に記載の技術）を使用して、ハニカム構造体の周縁部を隔壁が傾きをなすように除去加工し、最外周に位置する流路が外部との間の隔壁を有しないことによって外部に開口して概略軸方向に延びる凹溝を形成したセラミックハニカム本体の前記凹溝を充填して外表面を形成する外周壁を形成する。この場合隔壁を備えたセラミックハニカム本体と外周壁の熱膨張係数を一致させることは、困難であるため、このようなセラミックハニカム構造体が排気ガスで急熱されると、セラミックハニカム構造体の中心部の温度が上昇する一方、外壁部は把持部材、金属容器を介して外気温度に接しており外周壁部の温度は上昇しにくいため、中心部と外壁部の温度差により、外表面に引張応力が作用、クラックが発生し、強固に固着している外壁部と凹溝界面を貫通し、隣接した流路の隔壁へと連鎖的に進展するようになることがあった。隔壁にクラックが進展すると、隔壁が脱落して排ガスの浄化性能が低下したり、微粒子捕集用フィルタの場合は、入口側と出口側の流路が連通してしまうため、微粒子の捕集率が低下するといった、排気ガス浄化装置の浄化性能に係わる、極めて重要な問題に発展することがあった。このため、隔壁で囲まれた多数の流路のうち、最外周に位置する流路が、外部との間の隔壁を有しないことによって、外部に開口して軸方向に延びる凹溝を形成しているセラミックハニカム本体の、前記凹溝を充填して外表面を形成する外壁部を有するセラミックハニカム構造体において、図１３に示すように、前記外壁部と凹溝との間の少なくとも一部に空隙を有する場合には、ハニカム構造体の耐熱衝撃性が大幅に向上する。即ち、本発明のセラミックハニカム構造体が例えば排気ガスにより急熱された場合には、熱衝撃により外壁部に発生する応力をこの空隙が開放するため、外周壁に発生したクラックが隔壁に進展しにくくなるため、隔壁が脱落して排ガスの浄化性能が低下したり、微粒子捕集用フィルタの場合は、入口側と出口側の流路が連通し、微粒子の捕集率が低下するといった、排気ガス浄化装置の浄化性能に係わる、致命的な問題に発展することを防ぐことが出来る。また、本発明のセラミックハニカム構造体は、外壁部と凹溝を構成する隔壁の間の接着面積が小さくなることから、両者界面の熱膨張係数差により生じる残留応力が低減できるため、熱衝撃によるクラックが発生しにくいという効果も有している。 In the ceramic honeycomb structure of the present invention, the flow path located on the outermost periphery does not have a partition wall between the outside, so that the outside of the ceramic honeycomb body that opens to the outside and extends in the substantially axial direction is formed. It is preferable that an outer peripheral wall that fills the concave groove to form an outer surface is formed, and that at least a part between the member constituting the outer peripheral wall and the concave groove has a gap. Depending on the reason. In order to make the outer peripheral wall and the partition wall of the present invention incline and the end face of the honeycomb structure and the outer peripheral wall are substantially orthogonal to each other, a known technique (for example, techniques described in Patent Documents 4 and 5) is used. Then, the peripheral edge portion of the honeycomb structure is removed so that the partition walls are inclined, and the flow path located on the outermost periphery does not have the partition walls between the outside and opens to the outside so as to extend in the substantially axial direction. An outer peripheral wall forming an outer surface is formed by filling the concave grooves of the ceramic honeycomb body having the grooves. In this case, since it is difficult to match the thermal expansion coefficients of the ceramic honeycomb body having the partition walls and the outer peripheral wall, when such a ceramic honeycomb structure is rapidly heated by exhaust gas, the central portion of the ceramic honeycomb structure is However, the outer wall is in contact with the outside air temperature via the gripping member and metal container, and the temperature of the outer wall is hard to rise.Therefore, the tensile stress is applied to the outer surface due to the temperature difference between the center and the outer wall. However, there is a case where cracks are generated, and the outer wall and the groove interface firmly fixed are penetrated to progress to the partition walls of the adjacent flow paths. When cracks develop in the partition walls, the partition walls fall off, reducing the exhaust gas purification performance, or in the case of a particulate collection filter, the flow path on the inlet side and the outlet side communicates with each other. Has developed into a very important problem related to the purification performance of the exhaust gas purification device. For this reason, among the many flow paths surrounded by the partition walls, the flow path located at the outermost periphery does not have a partition wall between the outside, thereby forming a groove that opens to the outside and extends in the axial direction. In a ceramic honeycomb structure having an outer wall portion that fills the concave groove to form an outer surface of the ceramic honeycomb body, as shown in FIG. 13, at least a part between the outer wall portion and the concave groove When there is a void, the thermal shock resistance of the honeycomb structure is greatly improved. That is, when the ceramic honeycomb structure of the present invention is rapidly heated by, for example, exhaust gas, since the voids release the stress generated in the outer wall due to thermal shock, cracks generated in the outer peripheral wall propagate to the partition walls. Exhaust gas such that the partition wall drops off and the exhaust gas purification performance is reduced, or in the case of a particulate collection filter, the inlet and outlet channels are connected to reduce the particulate collection rate. It is possible to prevent the development of a fatal problem related to the purification performance of the gas purification device. In addition, the ceramic honeycomb structure of the present invention has a reduced adhesion area between the partition walls forming the outer wall portion and the recessed groove, so that the residual stress caused by the difference in thermal expansion coefficient between the two interfaces can be reduced. It also has the effect that cracks are less likely to occur.
本発明のセラミックハニカム構造体において、前記外壁部を構成する部材と凹溝の間に空隙を有する凹溝の個数割合が全凹溝のうちの５％以上であることが好ましいのは、前記外壁部を構成する部材と凹溝の間に空隙を有する凹溝が多数存在する場合には、熱衝撃応力を開放する観点からすれば、効果が大きいからである。２０％以上であれば更に好ましい。前記外壁部を構成する部材と凹溝の間に空隙部を有する凹溝の個数割合が９５％を超えると、凹溝を構成する隔壁と、外壁部を構成する部材間の接着面積が減少し、アイソスタティック強度が低下すると共に、外壁部がセラミックハニカム本体から剥離し易くなるため好ましくない。外壁部を構成する部材と凹溝の間に空隙を有する凹溝のより好ましい個数割合は全凹溝のうちの２０〜９０％である。 In the ceramic honeycomb structure of the present invention, it is preferable that a ratio of the number of concave grooves having a gap between a member constituting the outer wall portion and the concave groove is 5% or more of all the concave grooves. This is because, in the case where there are a large number of concave grooves having gaps between the members constituting the part and the concave grooves, the effect is great from the viewpoint of releasing the thermal shock stress. More preferably, it is 20% or more. If the ratio of the number of concave grooves having a gap portion between the member constituting the outer wall portion and the concave groove exceeds 95%, the bonding area between the partition wall constituting the concave groove and the member constituting the outer wall portion is reduced. It is not preferable because the isostatic strength is lowered and the outer wall portion is easily separated from the ceramic honeycomb body. A more preferable number ratio of the concave grooves having a gap between the member constituting the outer wall portion and the concave grooves is 20 to 90% of all the concave grooves.
ここで、外壁部を構成する部材と凹溝の間に空隙を有する凹溝とは、図１３に断面模式図で示すように隔壁で囲まれた多数のセルのうち、最外周に位置する流路が、外部との間の隔壁を有しないことによって、外部に開口して軸方向に延びる凹溝を形成しているセラミックハニカム本体の、前記凹溝の全領域が外周壁部材で充填されていない凹溝のことをいい、図１４に示すように、凹溝を構成する隔壁の端部５１、５４と凹溝を構成する隔壁の交点５２、５３で形成される凹溝長さ５１−５２−５３−５４のうち、外壁部を構成する部材と接触している部分の長さ即ち、接触部長さ５１−５５、５６−５７、５８−５４の合計長さの割合が９５％以下の凹溝のことをいう。ここで、外壁部を構成する部材と凹溝の間に形成された空隙について凹溝の一断面を用いて説明したが、この空隙は、ハニカム構造体の軸方向に連続的に形成されていると、ハニカム構造体全体に発生する熱衝撃応力を開放する意味で好ましい。但し、この空隙の形態は例えば図１３に示す形態が、軸方向全長に亘って全て同一である必要はなく、外壁部を構成する部材と隔壁の接触長さの割合がハニカム構造体の軸方向の位置によって異なっても、熱応力を開放する効果は有している。 Here, the concave groove having a gap between the member constituting the outer wall portion and the concave groove is a flow located on the outermost periphery among a large number of cells surrounded by a partition as shown in the schematic cross-sectional view of FIG. Since the passage does not have a partition wall between the outside and the outside, the entire region of the groove of the ceramic honeycomb body that is open to the outside and forms the groove extending in the axial direction is filled with an outer peripheral wall member. As shown in FIG. 14, the groove length 51-52 formed by the intersections 52, 53 of the partition walls 51, 54 and the partition walls 52, 53 forming the groove, as shown in FIG. -53-54, the length of the portion in contact with the member constituting the outer wall portion, that is, the concave portion whose ratio of the total length of the contact portion lengths 51-55, 56-57, 58-54 is 95% or less It means a groove. Here, the gap formed between the member constituting the outer wall portion and the concave groove has been described using one cross section of the concave groove, but this void is continuously formed in the axial direction of the honeycomb structure. And is preferable in terms of releasing thermal shock stress generated in the entire honeycomb structure. However, for example, the form of the gap shown in FIG. 13 does not have to be the same over the entire length in the axial direction, and the ratio of the contact length between the member constituting the outer wall portion and the partition wall is the axial direction of the honeycomb structure. Even if the position differs depending on the position, there is an effect of releasing the thermal stress.
図１８は、本発明のセラミックハニカム構造体の隔壁に沿って切断した２等分割断面において、隔壁の長手方向端部１１ｂ−ｔが外周壁１１ａと接する箇所の拡大模式図を示している。本発明のセラミックハニカム構造体は、隔壁が外周壁に対して傾いていることから、最外周に位置して外部に開口して延びる凹溝は複数存在し、外周壁を形成する部材は、複数の凹溝に充填される。 FIG. 18 is an enlarged schematic view of a portion where the longitudinal end portion 11b-t of the partition wall is in contact with the outer peripheral wall 11a in a bisection section cut along the partition wall of the ceramic honeycomb structure of the present invention. In the ceramic honeycomb structure of the present invention, since the partition walls are inclined with respect to the outer peripheral wall, there are a plurality of concave grooves that are located at the outermost periphery and open to the outside, and there are a plurality of members that form the outer peripheral wall. The groove is filled.
本発明のセラミックハニカム構造体において、最外周に位置する流路が外部との間の隔壁を有しないことによって外部に開口して概略軸方向に延びる凹溝を形成しているセラミックハニカム本体の、前記凹溝を充填して外表面を形成する外周壁が形成されており、外周壁の少なくとも一部に外表面に開口した空隙を有していることが好ましいのは以下の理由による。即ち、本発明のセラミックハニカム構造体が例えば排気ガスにより急熱された場合には、予め外周壁の外表面に開口した空隙が形成されていることから、当該空隙の開口幅が拡大することによって、外周壁に作用する熱衝撃応力が開放されるため、熱衝撃によるクラックが、外周壁と隔壁との接合界面を超え、隔壁に進展することを防げるからである。このため、隔壁が脱落して排ガスの浄化性能が低下したり、微粒子捕集用フィルタの場合は、入口側と出口側の流路が連通し、微粒子の捕集率が低下するといった、排気ガス浄化装置の浄化性能に係わる、致命的な問題に発展することを防ぐことが出来るのである。 In the ceramic honeycomb structure of the present invention, the flow path located on the outermost periphery does not have a partition wall between the outside, so that the outside of the ceramic honeycomb body that opens to the outside and extends in the substantially axial direction is formed. An outer peripheral wall that fills the concave groove to form an outer surface is formed, and it is preferable that at least a part of the outer peripheral wall has a gap opened to the outer surface for the following reason. That is, when the ceramic honeycomb structure of the present invention is rapidly heated by, for example, exhaust gas, a gap opened in advance on the outer surface of the outer peripheral wall is formed, so that the opening width of the gap is increased. This is because the thermal shock stress acting on the outer peripheral wall is released, so that cracks due to thermal shock can be prevented from exceeding the joint interface between the outer peripheral wall and the partition wall and progressing to the partition wall. For this reason, exhaust gas in which the partition wall is dropped and the exhaust gas purification performance is reduced, or in the case of a particulate collection filter, the inlet and outlet passages communicate with each other and the particulate collection rate decreases. It is possible to prevent the development of a fatal problem related to the purification performance of the purification device.
ここでいう外表面に開口した空隙とは外表面における開口幅が代表的には２μｍ以上で長さ１００μｍ以上の細長い形状のものを指し、外周壁に形成された気孔とは区別されるものである。例えば、図１５に模式図に示すように、空隙部４１は、軸方向に延びる凹溝１８に充填された外周壁１１ａの外表面に形成されており、その深さ方向の先端は、外周壁内で閉じている場合や、凹溝１８まで到達している場合等がある。意図的に形成した、この空隙部を外表面側から観察した走査型電子顕微鏡写真を図１６に示す。 The voids opened on the outer surface as used herein refer to elongated shapes having an opening width on the outer surface of typically 2 μm or more and a length of 100 μm or more, and are distinguished from pores formed on the outer peripheral wall. is there. For example, as shown in the schematic diagram of FIG. 15, the gap 41 is formed on the outer surface of the outer peripheral wall 11 a filled in the groove 18 extending in the axial direction, and the tip in the depth direction is the outer peripheral wall. In some cases, or when the groove 18 is reached. FIG. 16 shows a scanning electron micrograph of the void formed intentionally observed from the outer surface side.
また、外表面に開口した空隙は図１７（ａ）（ｂ）（ｃ）に示すように、軸方向に存在する場合のみならず、図１７（ｄ）（ｅ）に示すように円周方向等に存在しても良いし、図１７（ｆ）に示すように亀甲状に存在しても、前記述べたように熱衝撃による応力を開放する効果がある。 Moreover, as shown in FIGS. 17A, 17B, and 17C, the air gaps opened on the outer surface exist not only in the axial direction but also in the circumferential direction as shown in FIGS. 17D and 17E. Even if it exists in the shape of a turtle shell as shown in FIG. 17 (f), it has the effect of releasing stress due to thermal shock as described above.
ここで、前記外表面に開口した空隙の長さの合計がセラミックハニカム構造体全長の１倍以上であることが好ましいとしたのは、空隙が多数存在すれば、熱衝撃応力を開放する観点からすれば、効果が大きいのであるが、空隙の長さの合計がセラミックハニカム構造体全長の１倍以上あれば、少なくともハニカム構造体の外周壁に発生する熱衝撃応力の円周方向成分をセラミックハニカム構造体の全長に亘って開放できることから、熱衝撃性向上の効果が得られるためである。ここで、空隙の長さの合計とは、ハニカム構造体１ケ中の外表面に開口した空隙の長さの合計のことであり、ハニカム構造体１ヶ中に複数存在する場合はこれらの総和で表す。例えば、図１７（ａ）は、空隙の長さの合計がセラミックハニカム構造体全長の１倍に相当し、図１７（ｃ）は、空隙の長さの合計がセラミックハニカム構造体全長の１倍より少し大きい場合に相当する。尚、空隙の長さの合計がセラミックハニカム構造体全長の３倍以上であれば、よりその効果が大きくなる。 Here, it is preferable that the total length of the voids opened on the outer surface is 1 time or more of the entire length of the ceramic honeycomb structure. From the viewpoint of releasing thermal shock stress if there are many voids. In this case, the effect is great. However, if the total length of the voids is one time or more of the total length of the ceramic honeycomb structure, at least the circumferential component of the thermal shock stress generated on the outer peripheral wall of the honeycomb structure is set to the ceramic honeycomb. This is because the effect of improving thermal shock can be obtained because the structure can be opened over the entire length. Here, the total of the lengths of the voids is the total of the lengths of the voids opened on the outer surface in one honeycomb structure, and when there are a plurality of the voids in one honeycomb structure, the sum of these lengths Represented by For example, in FIG. 17A, the total length of the voids corresponds to one time of the entire length of the ceramic honeycomb structure, and in FIG. 17C, the total length of the voids is one time of the total length of the ceramic honeycomb structure. Corresponds to a slightly larger case. If the total length of the voids is at least three times the total length of the ceramic honeycomb structure, the effect is further increased.
また、本発明のセラミックハニカム構造体の隔壁の平均細孔径は１０〜４０μｍが良い。隔壁の気孔率との関係もあるが、隔壁の平均細孔径を１０〜４０μｍとしたのは、平均細孔径が１０μｍ未満であると圧力損失が大きくなり、平均細孔径が４０μｍを越えると微粒子が隔壁を通過して捕集効率が低下し、また強度も低下するため、微粒子捕集用フィルタとして適さないからである。なお、気孔率及び平均細孔径は、水銀ポロシメータを用いて測定する。 The average pore diameter of the partition walls of the ceramic honeycomb structure of the present invention is preferably 10 to 40 μm. Although there is a relationship with the porosity of the partition wall, the average pore diameter of the partition wall is set to 10 to 40 μm. When the average pore diameter is less than 10 μm, the pressure loss increases, and when the average pore diameter exceeds 40 μm, fine particles are formed. This is because the collection efficiency is lowered through the partition walls, and the strength is also lowered, so that it is not suitable as a filter for collecting fine particles. The porosity and average pore diameter are measured using a mercury porosimeter.
本発明のセラミックハニカム構造体の隔壁厚は０．１〜０．５ｍｍが好ましく、隔壁のピッチは１．３ｍｍ以上が好ましい。隔壁厚が０．１ｍｍ未満の場合は、特に外径が１５０ｍｍを越えるようなセラミックハニカム構造体を製造する際に隔壁の強度が低下し、好ましくない。一方、隔壁厚が０．５ｍｍを超える場合は、セラミックハニカム構造体の排気ガスに対する隔壁の通気抵抗が大きくなり、圧力損失が大きくなるからである。より好ましい隔壁厚さは、０．２〜０．４ｍｍである。また、隔壁のピッチが１．３ｍｍ未満の場合は、セラミックハニカム構造体の流路の開口面積が小さくなることから、セラミックハニカム構造体の入口の圧力損失が大きくなるためである。セラミックハニカム構造体の圧力損失が大きくなると、エンジンの出力低下につながることから好ましくない。 The partition wall thickness of the ceramic honeycomb structure of the present invention is preferably 0.1 to 0.5 mm, and the partition wall pitch is preferably 1.3 mm or more. In the case where the partition wall thickness is less than 0.1 mm, the strength of the partition walls is lowered particularly when a ceramic honeycomb structure having an outer diameter exceeding 150 mm is produced, which is not preferable. On the other hand, when the partition wall thickness exceeds 0.5 mm, the ventilation resistance of the partition wall to the exhaust gas of the ceramic honeycomb structure increases, and the pressure loss increases. A more preferable partition wall thickness is 0.2 to 0.4 mm. Further, when the partition wall pitch is less than 1.3 mm, the opening area of the flow path of the ceramic honeycomb structure becomes small, and the pressure loss at the inlet of the ceramic honeycomb structure becomes large. If the pressure loss of the ceramic honeycomb structure increases, it is not preferable because it leads to a decrease in engine output.
本発明のセラミックハニカム構造体の隔壁を構成するセラミック材料としては、本発明が主にディーゼルエンジンの排気ガス中の微粒子を除去するためのフィルタや触媒担体として使用されるため、耐熱性に優れた材料を使用することが好ましく、コージェライト、アルミナ、ムライト、窒化珪素、炭化珪素及びＬＡＳからなる群から選ばれた少なくとも１種を主結晶とするセラミック材料を用いることが好ましい。中でも、コージェライトを主結晶とするセラミックハニカム構造体は、安価で耐熱性、耐化学性に優れ、また低熱膨張であることから最も好ましい。 The ceramic material constituting the partition walls of the ceramic honeycomb structure of the present invention is excellent in heat resistance because the present invention is mainly used as a filter or catalyst carrier for removing fine particles in exhaust gas of a diesel engine. It is preferable to use a material, and it is preferable to use a ceramic material whose main crystal is at least one selected from the group consisting of cordierite, alumina, mullite, silicon nitride, silicon carbide, and LAS. Among these, a ceramic honeycomb structure having cordierite as a main crystal is most preferable because it is inexpensive, excellent in heat resistance and chemical resistance, and has low thermal expansion.
本発明のセラミックハニカム構造体において、外周壁を構成する部材としては、本発明が凹溝を構成する隔壁と、該凹溝に充填された外周壁の熱膨張係数差は小さい方が好ましいが、これに限定する必要はなく、隔壁を構成する材料に対して適宜選定すれば良い。例えばコージェライト、アルミナ、ムライト、窒化珪素、炭化珪素及びＬＡＳから選ばれたセラミック材料としても良いし、コージェライト、シリカ、アルミナ、ムライト、炭化珪素、窒化珪素等から選ばれる耐熱性セラミックス骨材粒子に無機バインダー、必要に応じてセラミックファイバー、セメント等を添加したものを適宜選択すれば良い。 In the ceramic honeycomb structure of the present invention, as the member constituting the outer peripheral wall, it is preferable that the present invention has a smaller difference in thermal expansion coefficient between the partition wall forming the concave groove and the outer peripheral wall filled in the concave groove. It is not necessary to limit to this, What is necessary is just to select suitably with respect to the material which comprises a partition. For example, a ceramic material selected from cordierite, alumina, mullite, silicon nitride, silicon carbide and LAS, or a heat-resistant ceramic aggregate particle selected from cordierite, silica, alumina, mullite, silicon carbide, silicon nitride, etc. It is only necessary to appropriately select an inorganic binder and ceramic fiber, cement, or the like, if necessary.
本発明のセラミックハニカム構造体の外周壁近傍において流路端部が隣接する流路同士が目封止されていることが好ましい。即ち図１９に示すように、両端部が封じられた流路が形成されることにより、これらの流路では排気ガスの流通が起こりにくいことから、断熱層として機能し、排気ガスの熱がハニカム構造体内部からから外周壁を介して金属製収納容器へ伝わりにくくなり、排ガスの浄化効率が改善されるからである。また、外周壁近傍の流路端部が目封止材で補強されることからセラミックハニカム構造体の端面角部の破損が発生しにくくなり、結果としてセラミックハニカム構造体の強度が改善され、支持部材の支持力や、使用時の機械的振動や衝撃により破損しにくくなるからである。 In the vicinity of the outer peripheral wall of the ceramic honeycomb structure of the present invention, it is preferable that the flow paths adjacent to the flow path ends are plugged. That is, as shown in FIG. 19, since the passages sealed at both ends are formed, the exhaust gas hardly flows through these passages. This is because it is difficult to transmit from the inside of the structure to the metal storage container through the outer peripheral wall, and the exhaust gas purification efficiency is improved. In addition, since the end of the flow path near the outer peripheral wall is reinforced with the plugging material, the corners of the end face of the ceramic honeycomb structure are less likely to break, resulting in improved strength of the ceramic honeycomb structure and support. It is because it becomes difficult to be damaged by the supporting force of the member, mechanical vibration or impact during use.
上記観点から、本発明のセラミックハニカム構造体において、外周壁近傍の流路端部が隣接する流路同士が目封止されている目封止材のハニカム構造体端面からの長さがセラミックハニカム構造体フィルタの全長の８．２％以下が好ましく、且つ、隣接する流路同士の目封止されている範囲が、セラミックハニカム構造体端面の外周壁からハニカムフィルタ端面の中心に向かって、最大５×（隔壁ピッチ）の長さの範囲に存在する流路であることが好ましい。 From the above viewpoint, in the ceramic honeycomb structure of the present invention, the length from the end face of the honeycomb structure of the plugging material in which the flow paths adjacent to the flow path near the outer peripheral wall are plugged is the ceramic honeycomb structure. The total length of the structure filter is preferably 8.2% or less, and the range where the adjacent flow paths are plugged is the maximum from the outer peripheral wall of the end face of the ceramic honeycomb structure toward the center of the end face of the honeycomb filter. It is preferable that the flow path exists within a range of a length of 5 × (partition wall pitch).
以上、本発明のセラミックハニカム構造体の作用効果について、主にセラミックハニカム構造体の流路の所望部位を目封止したセラミックハニカムフィルタを例にあげて説明したが、流路を目封止せずに触媒物質を担持したセラミックハニカム構造体であっても、外周壁に対して傾いた隔壁を有していると、傾いた隔壁で排気ガスの流れに乱れが生じて、担持された触媒物質に、効果的に排気ガスが接触して、浄化効率が高くなるという観点からすると、同様の効果があるということは、言うまでもない。 As described above, the operation and effect of the ceramic honeycomb structure of the present invention has been described mainly using the ceramic honeycomb filter in which a desired portion of the flow path of the ceramic honeycomb structure is plugged as an example, but the flow path is not plugged. Even if the ceramic honeycomb structure is loaded with a catalyst material, it has a partition wall that is inclined with respect to the outer peripheral wall. Needless to say, the same effect can be obtained from the viewpoint of effective exhaust gas contact and high purification efficiency.
本発明のセラミックハニカムフィルタの製造方法概略について以下説明する。
図３及び図５の断面模式図を有する本発明のセラミックハニカムフィルタを、図９の製造工程を模式断面で示した図面により説明する。（ａ）ハニカム構造の押出成形体を乾燥して、隔壁３１ｂに囲まれた流路３１ｃを有するハニカム乾燥体を得た後、（ｂ）このハニカム乾燥体の外周部３５を加工除去する。（ｃ）この際を隔壁３１ｂに対して加工除去した後のハニカム乾燥体の外周部３６が傾くように加工し、最外周部に、外部との間の隔壁を有しないことによって、外部に開口して概略軸方向に延びる凹溝を有するハニカム構造の乾燥体とする。（ｄ）次いでハニカム乾燥体の両端部を加工除去する。この際、外周部３６に対して加工除去した後のハニカム乾燥体の端面３８が略直角になるように加工する。（ｅ）流路３１ｃの所望の端部に目封止材３９を充填して焼成する。（ｆ）次いで、ハニカム乾燥体の外周部３６の表面に形成された凹溝に外周壁用コート材３１ａを充填、塗布して外周壁部を形成し、必要に応じて焼成操作を行い、隔壁、目封止材、外周壁部を一体化させることによりセラミックハニカムフィルタが得られる。このように、乾燥体の外周部を隔壁と傾くように加工除去することから、外周壁形成前の外観は、図４及び図６に示すような形態とすることができる。また、（ｅ）の目封止材と（ｆ）外周壁の焼成を同時に行う方法を採用することもできる。また、ハニカム乾燥体を焼成した上で、図９（ｂ）以降の工程を採用することもできる。即ち、ハニカム焼成体の外周壁に対して隔壁が傾くようにハニカム焼成体の外周部を加工除去した後、外周面に外周壁用コート材を塗布、目封止材を充填した上で、外周壁と目封止部を焼成する方法も必要に応じて採用できる。
An outline of the method for producing the ceramic honeycomb filter of the present invention will be described below.
The ceramic honeycomb filter of the present invention having the schematic cross-sectional views of FIGS. 3 and 5 will be described with reference to the drawings showing the manufacturing process of FIG. 9 in schematic cross-section. (A) After drying the extrusion-molded body having a honeycomb structure to obtain a honeycomb dried body having a channel 31c surrounded by the partition walls 31b, (b) the outer peripheral portion 35 of the honeycomb dried body is processed and removed. (C) The honeycomb dried body after being processed and removed with respect to the partition wall 31b is processed so that the outer peripheral portion 36 is inclined, and the outermost peripheral portion has no partition wall between the outside, thereby opening to the outside. Thus, a dried honeycomb structured body having concave grooves extending substantially in the axial direction is obtained. (D) Next, both ends of the dried honeycomb body are processed and removed. At this time, the end face 38 of the dried honeycomb body after being processed and removed with respect to the outer peripheral portion 36 is processed so as to be substantially perpendicular. (E) A plugging material 39 is filled into a desired end of the flow path 31c and fired. (F) Next, the outer peripheral wall coating material 31a is filled and applied to the concave grooves formed on the surface of the outer peripheral portion 36 of the dried honeycomb body to form the outer peripheral wall portion, and a firing operation is performed as necessary. A ceramic honeycomb filter can be obtained by integrating the plugging material and the outer peripheral wall portion. Thus, since the outer peripheral part of the dry body is processed and removed so as to be inclined with respect to the partition wall, the appearance before the outer peripheral wall is formed can be configured as shown in FIGS. 4 and 6. It is also possible to employ a method in which the plugging material (e) and (f) the outer peripheral wall are fired simultaneously. Further, after firing the dried honeycomb body, the steps after FIG. 9B can be adopted. That is, after processing and removing the outer peripheral portion of the honeycomb fired body so that the partition wall is inclined with respect to the outer peripheral wall of the honeycomb fired body, the outer peripheral surface is coated with a coating material for the outer peripheral wall and filled with the plugging material. A method of firing the wall and the plugged portion can be adopted as necessary.
図７に断面模式図、及び図８に外周壁を形成する前の外観模式図を示す形態の本発明のセラミックハニカム構造体は、押出成形機により、図１０に示すように押出成形機により縦方向にハニカム構造の成形体を押し出す過程で、ハニカム成形体の重量を支えるために付加する保持力の方向、大きさを調整することにより、流路が長手方向に対して湾曲したハニカム成形体を得る。そして、このようにして得られたハニカム成形体を乾燥した後、図３で示したハニカムフィルタと同様に、ハニカム乾燥体或いはハニカム焼成体の外周壁に対して隔壁が傾くように加工除去した後、外周面に外周壁用コート材を塗布、外周壁を形成し、流路の所望の端部に目封止材を充填して目封止部を形成する。 The ceramic honeycomb structure of the present invention having a cross-sectional schematic diagram in FIG. 7 and an external schematic diagram before forming the outer peripheral wall in FIG. 8 is longitudinally processed by an extruder, as shown in FIG. In the process of extruding the honeycomb structure formed body in the direction, by adjusting the direction and size of the holding force applied to support the weight of the honeycomb formed body, the honeycomb formed body in which the flow path is curved with respect to the longitudinal direction is obtained. obtain. Then, after drying the honeycomb formed body obtained in this way, the processed honeycomb is removed so that the partition walls are inclined with respect to the outer peripheral wall of the honeycomb dried body or the honeycomb fired body as in the honeycomb filter shown in FIG. Then, an outer peripheral wall coating material is applied to the outer peripheral surface, an outer peripheral wall is formed, and a plugging material is filled into a desired end of the flow path to form a plugged portion.
ここで、本発明の好ましい形態である、外周壁を構成する部材と凹溝の間に空隙を有するセラミックハニカム構造体を製造するには、最外周に位置する流路が、外部との間の隔壁を有しないことによって、外部に開口して軸方向に延びる凹溝に粘度を２００００ｃＰ以上に調整したコート材を塗布、充填させた後、乾燥させる。特許文献４の方法のように、１００００ｃＰ〜２００００ｃＰの粘度を有するコート材を塗布した場合には、凹溝１２の角隅部にまでコート材が充填されるのであるが、コート材の粘度を例えば２００００ｃＰ以上の高粘度とすることにより、図１３及び図１４に示すように凹溝の角隅部までコート材が充填されないため、外壁部を構成する部材と凹溝との間に空隙を有するセラミックハニカム構造体が得られる。尚、コート材の粘度を２００００ｃＰ以上の高粘度にするには、骨材、無機バインダ−や有機バインダーの種類や添加量、水分量等を調整することにより可能となる。また、コート材の乾燥が終了した後は、必要に応じてコート材の焼成を行っても良い。 Here, in order to produce a ceramic honeycomb structure having a gap between the member constituting the outer peripheral wall and the groove, which is a preferred embodiment of the present invention, the flow path located on the outermost periphery is between the outside and the outside. By not having a partition wall, a coating material whose viscosity is adjusted to 20000 cP or more is applied to and filled in a groove that opens to the outside and extends in the axial direction, and then dried. When a coating material having a viscosity of 10000 cP to 20000 cP is applied as in the method of Patent Document 4, the coating material is filled up to the corners of the grooves 12. Since the coating material is not filled up to the corners of the grooves as shown in FIGS. 13 and 14 by setting the viscosity to 20000 cP or higher, the ceramic having a gap between the members constituting the outer wall and the grooves. A honeycomb structure is obtained. In addition, in order to make the viscosity of a coating material into 20000 cP or more high viscosity, it becomes possible by adjusting the kind, addition amount, moisture content, etc. of an aggregate, an inorganic binder, and an organic binder. Further, after the drying of the coating material is completed, the coating material may be fired as necessary.
更に本発明の好ましい形態である、外表面に開口した空隙を有するセラミックハニカム構造体を製造するには、例えば、セラミックハニカム構造体の最外周に位置するセルが、外部との間の隔壁を有しないことによって、外部に開口して軸方向に延びる凹溝にセラミック骨材及び無機バインダからなるコート材を塗布、充填させ、例えば７０℃以上に加熱させられた乾燥炉に、投入してコート材中に含まれる水分を急速乾燥することにより、コート材表面に開口した空隙部を形成させることができる。この空隙が発生するのは急速乾燥によりコーティングされたコート材の表面と内部の水分量に差が生じ、表面と内部の乾燥収縮量の差が発生するからである。このとき、コート材中の骨材、無機バインダ−や有機バインダーの種類や添加量、水分量、或いは乾燥炉の温度を調整することにより、外表面に開口した空隙の発生割合、空隙の開口幅、空隙の形態を変化させることができるが、無機バインダの添加量や水分量を増加させると空隙は発生し易くなる。なお、コート材の乾燥が終了した後は、必要に応じてコート材の焼成を行っても良い。 Furthermore, in order to manufacture a ceramic honeycomb structure having voids opened on the outer surface, which is a preferred embodiment of the present invention, for example, cells located on the outermost periphery of the ceramic honeycomb structure have partition walls between the outside. The coating material made of ceramic aggregate and inorganic binder is applied to and filled in the groove that opens to the outside and extends in the axial direction. For example, the coating material is put into a drying furnace heated to 70 ° C. or more. By rapidly drying the moisture contained therein, an open space can be formed on the surface of the coating material. The reason why the voids are generated is that a difference occurs in the amount of moisture between the surface and the inside of the coating material coated by rapid drying, and a difference in the amount of drying shrinkage between the surface and the inside occurs. At this time, by adjusting the type and amount of the aggregate, inorganic binder and organic binder in the coating material, the amount of moisture, or the temperature of the drying furnace, the generation ratio of the voids opened on the outer surface, the opening width of the voids Although the shape of the voids can be changed, voids are easily generated when the amount of inorganic binder added or the amount of moisture is increased. In addition, after drying of a coating material is complete | finished, you may bak a coating material as needed.
尚、本発明は上記で示した図３〜８に示す形態に限定されるものではなく、流路に流入した排気ガスが、隔壁で曲げられ、流れに乱れを生じさせるとともに、最適な細孔構造を有する隔壁で微粒子を捕集するという、本発明の技術的思想に基づけば図１１に示す各種形態も本発明に含まれるものである。 In addition, this invention is not limited to the form shown to FIGS. 3-8 shown above, The exhaust gas which flowed into the flow path is bent by a partition, and it produces a disorder | damage | failure in a flow, and optimal pore Various forms shown in FIG. 11 are also included in the present invention based on the technical idea of the present invention in which fine particles are collected by a partition having a structure.
以上詳細に説明のとおり、本発明のセラミックハニカム構造体は、該セラミックハニカム構造体の端面と外周壁が略直交し、該外周壁が略円筒形状であり、前記隔壁の表面粗さＲｙが１０μｍ以上であり、且つ長手方向断面において隣り合う隔壁が略平行であると共に外周壁に対して少なくとも一部の隔壁が傾いていることから、例えばセラミックハニカムフィルタとして使用した場合、隔壁の長手方向がハニカムフィルタ外周壁または排気ガス流入方向と平行の場合に比べて、セル壁の長手方向に略均一に微粒子を分散させることができるので、フィルタ再生を行う場合でも微粒子の部分的な堆積に伴う部分的で急激な温度上昇を抑えることができるため、隔壁の溶損や破損を防げるのと共に、触媒による微粒子の燃焼浄化を行う場合でも長期間に亘り使用できる。更に金属容器への収納時の不具合や、使用時の機械的衝撃や熱衝撃による破損を防げるという効果も有している。 As described above in detail, in the ceramic honeycomb structure of the present invention, the end face and the outer peripheral wall of the ceramic honeycomb structure are substantially orthogonal, the outer peripheral wall is substantially cylindrical, and the surface roughness Ry of the partition wall is 10 μm. In the longitudinal section, adjacent partition walls are substantially parallel and at least a part of the partition walls is inclined with respect to the outer peripheral wall. For example, when used as a ceramic honeycomb filter, the longitudinal direction of the partition walls is honeycomb. Compared with the case of parallel to the filter outer peripheral wall or the exhaust gas inflow direction, the fine particles can be dispersed substantially uniformly in the longitudinal direction of the cell wall. Because it can suppress a sudden temperature rise, it can prevent melting and breakage of the partition wall, and even when performing combustion purification of fine particles with a catalyst Over a period of time it can be used. Furthermore, it has the effect of preventing problems during storage in a metal container and damage due to mechanical or thermal shock during use.
以下、本発明の実際の実施例を説明する。
（実施例１〜５）
カオリン、タルク、シリカ、水酸化アルミ、アルミナなどの粉末を調整して、質量比で、ＳｉＯ2 ：４７〜５３％、Ａｌ2Ｏ3：３２〜３８％、ＭｇＯ：１２〜１６％及びＣａＯ、Ｎａ2Ｏ 、Ｋ2Ｏ、ＴｉＯ2、Ｆｅ2Ｏ3、ＰｂＯ、Ｐ2Ｏ5などの不可避的に混入する成分を全体で２．５％含むようなコージェライト生成原料粉末を得た後に、メチルセルロースとヒドロキシプロピルメチルセルロース等の成形バインダー及びグラファイトからなる造孔剤を添加し、規定量の水を注入して充分な混合、混練を行い、可塑化可能な坏土を作製した。
Hereinafter, actual embodiments of the present invention will be described.
(Examples 1-5)
Kaolin, talc, silica, aluminum hydroxide, to adjust the powder, such as alumina, in a mass ratio, SiO 2: 47~53%, Al 2 O 3: 32~38%, MgO: 12~16% , and CaO, After obtaining a cordierite-producing raw material powder containing 2.5% in total of components inevitably mixed such as Na 2 O, K 2 O, TiO 2, Fe 2 O 3 , PbO, P 2 O 5 , A molding binder such as methylcellulose and hydroxypropylmethylcellulose and a pore-forming agent made of graphite were added, and a prescribed amount of water was injected, and sufficient mixing and kneading were carried out to prepare a plasticizable clay.
次に、公知の構造の押出成形用金型を用いて、押出成形し、得られたハニカム構造の成形体を乾燥することにより、外径３００ｍｍ長さ３５０ｍｍの寸法を有し、隔壁により囲まれた多数の流路を有するハニカム構造の乾燥体を作製した。その後、図９に示す製造方法により、隔壁が外周に対して傾くように、外周部及び両端面を加工除去した後、公知の方法で目封止部を形成して焼成した上で、外径２６４ｍｍ、長さ３０５ｍｍ、隔壁のピッチ１．５ｍｍ、隔壁の厚さ０．３ｍｍで隔壁の気孔率が６３％、隔壁の表面粗さが最大高さＲyで５５μｍであり、隔壁が外周に対し各種傾きを有し、且つ最外周に位置する流路が外部との間に隔壁を有しないことによって、外部に開口して軸方向に延びる凹溝を形成しているセラミックハニカム本体を作製した。一方、外周壁のコート材として、平均粒径２０μｍのコージェライト粉末Ａ、１００質量部に対して、コロイダルシリカを固形分で１０質量部配合し、これにメチルセルロース、水を加えて混練し、粘度３５０００ｃＰのコート材を準備した。次いで、前記準備した外周に凹溝を有するハニカム本体の外周部に塗布した上で、４０℃２４時間乾燥した後、７０℃で１２時間乾燥させた。その後４５０℃まで加熱して、前記メチルセルロースを分解すると共に、凹溝と外周壁が強固に一体化された外径２６７ｍｍ、長さ３０５ｍｍ、隔壁の間隔１．５２ｍｍ、隔壁の厚さ０．３ｍｍで、端面と外周壁が略直交し、外周壁が略円筒形状であり、長手方向断面において外周壁に対して隔壁が傾いている図３〜図６に示す形態のセラミックハニカムフィルタを作製した。このとき、外周部を加工除去する際に、隔壁に沿って切断した２等分割断面において、隔壁の長手方向端部が外周壁と接する隔壁を１〜６ケ存在させるように調整して表１に示す実施例１〜５の５種類のハニカムフィルタを作製した。ここで、隔壁の表面粗さである最大高さＲyは、ミツトヨ製表面粗さ計ＳＵＲＦＴＥＳＴにより、先端の曲率半径５μｍの触針を用いて、隔壁表面を長手方向２ｍｍに亘って測定して、ＪＩＳ Ｂ
０６０１−１９９４に準じて求め、３ケ所の測定値の平均とした。
Next, extrusion molding is performed using a mold for extrusion molding having a known structure, and the obtained honeycomb structure molded body is dried, so that the outer diameter is 300 mm and the length is 350 mm. A dried honeycomb structure having a large number of flow paths was prepared. Thereafter, by the manufacturing method shown in FIG. 9, the outer peripheral portion and both end faces are processed and removed so that the partition wall is inclined with respect to the outer periphery, and then the plugging portion is formed and fired by a known method, and the outer diameter 264 mm, length 305 mm, partition pitch 1.5 mm, partition wall thickness 0.3 mm, partition wall porosity 63%, partition wall surface roughness 55 mm in maximum height Ry A ceramic honeycomb body in which a channel having an inclination and located on the outermost periphery does not have a partition wall between the outside and the outside is formed into a groove that opens to the outside and extends in the axial direction. On the other hand, as a coating material for the outer peripheral wall, 10 parts by mass of colloidal silica in a solid content with respect to 100 parts by mass of cordierite powder A having an average particle diameter of 20 μm, kneaded with adding methylcellulose and water to this, the viscosity A coating material of 35000 cP was prepared. Subsequently, after apply | coating to the outer peripheral part of the honeycomb main body which has a concave groove in the prepared outer periphery, after drying for 24 hours at 40 degreeC, it was made to dry for 12 hours at 70 degreeC. Thereafter, the mixture was heated to 450 ° C. to decompose the methylcellulose, and the outer diameter wall was 267 mm, the length was 305 mm, the partition interval was 1.52 mm, and the partition wall thickness was 0.3 mm. A ceramic honeycomb filter having the form shown in FIGS. 3 to 6 was produced in which the end face and the outer peripheral wall were substantially orthogonal, the outer peripheral wall was substantially cylindrical, and the partition walls were inclined with respect to the outer peripheral wall in the longitudinal section. At this time, when the outer peripheral portion is processed and removed, in the equally divided section cut along the partition wall, adjustment is made so that 1 to 6 partition walls are in contact with the outer peripheral wall at the longitudinal ends of the partition walls. Five types of honeycomb filters of Examples 1 to 5 shown in FIG. Here, the maximum height Ry, which is the surface roughness of the partition wall, is measured with a surface roughness meter SURFTEST made by Mitutoyo using a stylus with a curvature radius of 5 μm at the tip over the surface of the partition wall in the longitudinal direction of 2 mm. JIS B
It was calculated according to 0601-1994, and was taken as the average of the three measured values.
実施例１〜５のセラミックハニカム構造体の、隔壁に沿って切断した２等分割断面において、３本の流路の隔壁間隔を５０ｍｍ間隔で測定したところ、１．４９〜１．５５ｍｍであった。また、一方の端面に直角な曲面に対する他方の端面のずれ量は、最大０．３ｍｍであり、両端面から１２．７ｍｍの位置で等間隔に各４ケ所測定した外径寸法は、２６６〜２６８ｍｍであった。 In the equally divided cross section cut along the partition walls of the ceramic honeycomb structures of Examples 1 to 5, the partition wall spacing of the three channels was measured at 50 mm intervals, and was 1.49 to 1.55 mm. . Further, the maximum deviation of the other end surface with respect to the curved surface perpendicular to one end surface is 0.3 mm, and the outer diameter measured at four locations at equal intervals at positions of 12.7 mm from both end surfaces is 266 to 268 mm. Met.
得られた実施例１〜５のハニカムフィルタを図１２に示すように、金属容器に組み込んだ後、圧力損失、捕集率、及び耐溶損性の評価を行った。圧力損失は、圧力損失テストスタンドにて、空気流量１５Ｎｍ３／ｍｉｎの時のハニカムフィルタ入口側と出口側の差圧を圧力損失として評価を行った。捕集率は、ハニカムフィルタに対して、微粒子発生器により空気流量１０Ｎｍ3 ／ｍｉｎで、粒径０．０４２μｍのカーボン粉を３ｇ／ｈで２時間投入した際の、ハニカムフィルタが捕集したカーボン粉の重量と投入したカーボン粉の重量から、捕集率を算出した。耐溶損性は、ハニカムフィルタへのカーボン粉の投入を継続し、ハニカムフィルタに捕集された微粒子が６ｇ／Ｌとなるまで行った後、これらのハニカムフィルタを排気試験装置(図示せず)に装着し、バーナーによる燃焼ガスによりカーボン粉に着火させ、溶損発生の有無を確認して評価した。この時の昇温速度は毎秒１．６℃とし、６００℃到達後、燃焼ガスの導入を停止し、捕集されたカーボン粉による自己燃焼を行わせる。燃焼が終了し、冷却後のハニカムフィルタに対して、Ｘ線による内部溶損発生の有無の確認を行ったうえで、溶損が認められなかったものについては、捕集させるカーボン粉を２ｇ／Ｌづつ増加させ、溶損が発生するまで繰り返し溶損試験を行い、溶損が発生しなかったカーボン捕集量の最大値を耐溶損カーボン捕集量として耐溶損性の指標として表した。 As shown in FIG. 12, the obtained honeycomb filters of Examples 1 to 5 were assembled in a metal container, and then evaluated for pressure loss, collection rate, and resistance to erosion. The pressure loss was evaluated using a pressure loss test stand, with the differential pressure between the honeycomb filter inlet side and the outlet side when the air flow rate was 15 Nm 3 / min as the pressure loss. The collection rate is the carbon collected by the honeycomb filter when carbon powder having an air flow rate of 10 Nm 3 / min and a particle size of 0.042 μm is charged at 3 g / h for 2 hours with respect to the honeycomb filter. The collection rate was calculated from the weight of the powder and the weight of the charged carbon powder. Melt resistance was maintained by continuing to introduce carbon powder into the honeycomb filter until the amount of fine particles collected in the honeycomb filter reached 6 g / L, and then using these honeycomb filters in an exhaust test device (not shown). The carbon powder was ignited with combustion gas from a burner, and the presence or absence of melting damage was confirmed and evaluated. The heating rate at this time is 1.6 ° C. per second, and after reaching 600 ° C., the introduction of the combustion gas is stopped and self-combustion with the collected carbon powder is performed. After confirming whether or not internal erosion has occurred due to X-rays with respect to the honeycomb filter after the completion of combustion and cooling, the carbon powder to be collected is 2 g / It was increased in increments of L, and the erosion test was repeated until erosion occurred, and the maximum value of the amount of carbon that did not cause erosion was expressed as an index of erosion resistance as the amount of erosion-resistant carbon.
次に、作成した本発明例１〜５のセラミックハニカムフィルタに対して、耐熱衝撃温度の試験を行った。耐熱衝撃温度の評価試験は、一定温度（室温＋４００℃）に加熱された電気炉中にセラミックハニカムフィルタを挿入して３０分間保持し、その後室温に急冷した後、セラミックハニカムフィルタの軸方向両端面の目視観察を行い、隔壁に発生したクラックの有無を確認した。また、隔壁にクラックが発見されない場合は、電気炉の温度を２５℃上昇させ同様の試験を行い、クラックが発生するまで繰り返した。そしてクラックが発見されなかった最高温度差（加熱温度−室温）を耐熱衝撃温度とした。 Next, a test for the thermal shock temperature was performed on the ceramic honeycomb filters of Examples 1 to 5 according to the present invention. The evaluation test of the thermal shock temperature was conducted by inserting the ceramic honeycomb filter into an electric furnace heated to a constant temperature (room temperature + 400 ° C.), holding it for 30 minutes, and then rapidly cooling to room temperature, and then both end faces in the axial direction of the ceramic honeycomb filter Was visually observed to confirm the presence or absence of cracks in the partition walls. In addition, when no crack was found in the partition wall, the temperature of the electric furnace was increased by 25 ° C., the same test was performed, and the test was repeated until the crack was generated. And the maximum temperature difference (heating temperature-room temperature) where the crack was not discovered was made into the thermal shock temperature.
更に、耐熱衝撃温度が測定終了したハニカム構造体を軸方向に５等分に切断し、切断面での凹溝に充填され形成された外壁部形態の観察を、１切断面につき、９０°間隔で４カ所行い、全凹溝のうち外壁部を構成する部材と凹溝の間に空隙を有する凹溝の個数割合をカウントした。 Further, the honeycomb structure whose thermal shock temperature has been measured is cut into five equal parts in the axial direction, and observation of the outer wall portion formed by filling the concave grooves in the cut surface is performed at intervals of 90 ° per cut surface. The number ratio of the number of concave grooves having gaps between the concave grooves and the members constituting the outer wall portion among all the concave grooves was counted.
実施例１〜５のハニカムフィルタの、評価結果を表１に示す。ハニカムフィルタの端面と外周壁が略直交し、該外周壁が略円筒形状であり、前記隔壁の気孔率が６３％、隔壁の表面粗さが最大高さＲyで５５μｍであり、且つ隔壁に沿って切断した２等分割断面において、隔壁の長手方向端部が外周壁と接する隔壁を１〜６ケ存在させるようにしたことから、排気ガスの流入方向に対して隔壁が傾いて形成されているため圧力損失は２００ｍｍＨ２Ｏ以下、捕集率は９０％以上、耐溶損カーボン捕集量も１６ｇ／Ｌ以上であった。特に、隔壁の長手方向端部が外周壁と接する隔壁の数を多くした方が、耐溶損カーボン捕集量が大きくなっている。これらの溶損発生位置は、いずれも、排気ガス出口側の目封止部付近であることが確認され、排気ガス出口側の目封止部にカーボン粉が高濃度で堆積していたことが伺える。 Table 1 shows the evaluation results of the honeycomb filters of Examples 1 to 5. The end face of the honeycomb filter and the outer peripheral wall are substantially orthogonal, the outer peripheral wall is substantially cylindrical, the porosity of the partition wall is 63%, the partition wall surface roughness is 55 μm at the maximum height Ry, and along the partition wall In the two equally divided sections cut in this manner, the partition walls are inclined with respect to the inflow direction of the exhaust gas because the partition walls are arranged so that the longitudinal ends of the partition walls are in contact with the outer peripheral wall. Therefore, the pressure loss was 200 mmH 2 O or less, the collection rate was 90% or more, and the amount of collection of the erosion resistant carbon was 16 g / L or more. In particular, increasing the number of partition walls in which the end portions in the longitudinal direction of the partition walls are in contact with the outer peripheral wall increases the amount of sequestering carbon. It was confirmed that these melting damage occurrence positions were in the vicinity of the plugging portion on the exhaust gas outlet side, and carbon powder was deposited at a high concentration on the plugging portion on the exhaust gas outlet side. I can ask.
また、いずれのセラミックハニカムフィルタも外周壁と端面の交差部は略直角となっており鋭角部が存在せず、かつ、外周壁が略円筒形状であることから、金属容器に挿入する際に、外周壁と端面の交差部の破損の問題は発生しなかった。それと共に、最外周に位置する流路が外部との間の隔壁を有しないことによって外部に開口して概略軸方向に延びる凹溝を形成しているセラミックハニカム本体と、前記凹溝を充填している外周壁を構成する部材との間の少なくとも一部に空隙を有していることから、耐熱衝撃温度は実用上問題ないレベルである４５０℃以上の５００〜５５０℃が得られた。 In addition, any ceramic honeycomb filter has a substantially right angle at the intersection between the outer peripheral wall and the end face, and there is no acute angle part, and the outer peripheral wall has a substantially cylindrical shape. The problem of breakage at the intersection of the outer wall and the end face did not occur. At the same time, the flow path located on the outermost periphery does not have a partition wall between the outside and the ceramic honeycomb body which is opened to the outside and forms a groove extending in the general axial direction, and the groove is filled. Since there is a gap in at least a part between the members constituting the outer peripheral wall, a thermal shock temperature of 500 to 550 ° C. of 450 ° C. or higher, which is a practically no problem level, was obtained.
（比較例１）
実施例１において、外周壁部を加工除去する際に、隔壁に沿って切断した２等分割断面において、隔壁の長手方向端部が外周壁と接する隔壁が存在しないように調整した以外は、実施例１と同様の方法により、外径２６７ｍｍ、長さ３０５ｍｍ、隔壁のピッチ１．５ｍｍ、隔壁の厚さ０．３ｍｍで、端面と外周壁が略直交し、外周壁が略円筒形状であり、隔壁の気孔率が６３％、隔壁の表面粗さが最大高さＲyで５５μｍであり、隔壁に沿って切断した２等分割断面において、隔壁の長手方向端部が外周壁と接する隔壁が存在しない比較例１のハニカムフィルタを作製した。比較例１のセラミックハニカム構造体の、隔壁に沿って切断した２等分割断面において、３本の流路の隔壁間隔を５０ｍｍ間隔で測定したところ、１．４９〜１．５５ｍｍであった。また、一方の端面に直角な曲面に対する他方の端面のずれ量は、最大０．３ｍｍであり、両端面から１２．７ｍｍの位置で等間隔に各４ケ所測定した外径寸法は、２６６〜２６８ｍｍであった。
(Comparative Example 1)
In Example 1, when the outer peripheral wall portion was processed and removed, in the bisection section cut along the partition wall, the adjustment was performed so that there was no partition wall in which the longitudinal end portion of the partition wall was in contact with the outer peripheral wall. By the same method as in Example 1, the outer diameter is 267 mm, the length is 305 mm, the partition wall pitch is 1.5 mm, the partition wall thickness is 0.3 mm, the end surface and the outer peripheral wall are substantially orthogonal, and the outer peripheral wall is substantially cylindrical. The partition wall porosity is 63%, the partition wall surface roughness is 55 μm at the maximum height Ry, and there is no partition wall in which the longitudinal end of the partition wall is in contact with the outer peripheral wall in a bisected section cut along the partition wall A honeycomb filter of Comparative Example 1 was produced. In the equally divided cross section cut along the partition walls of the ceramic honeycomb structure of Comparative Example 1, the partition wall spacing of the three flow paths was measured at 50 mm intervals, and was 1.49 to 1.55 mm. Further, the maximum deviation of the other end surface with respect to the curved surface perpendicular to one end surface is 0.3 mm, and the outer diameter measured at four locations at equal intervals at positions of 12.7 mm from both end surfaces is 266 to 268 mm. Met.
比較例１のハニカムフィルタに対し、実施例１と同様、圧力損失、捕集率、耐溶損カーボン粉捕集量を測定した結果を、表１に記した。比較例１のハニカムフィルタは、隔壁に沿って切断した２等分割断面において、隔壁の長手方向端部が外周壁と接する隔壁が存在しない、即ち排気ガスの流入方向に対する隔壁の傾きが小さいため、圧力損失は２００ｍｍＨ２以下、捕集率は９０％以上であったものの、耐溶損カーボン粉捕集量は６ｇ／Ｌであり、実施例１〜５に比べて耐溶損性は低かった。また比較例１において、溶損が発生したカーボン捕集量（８ｇ／Ｌ）では、排気ガス出口側の目封止部付近が特に大きく溶損しているのが確認された。 For the honeycomb filter of Comparative Example 1, the results of measuring the pressure loss, the collection rate, and the erosion resistant carbon powder collection amount as in Example 1 are shown in Table 1. In the honeycomb filter of Comparative Example 1, in the bisection section cut along the partition wall, there is no partition wall where the longitudinal end of the partition wall is in contact with the outer peripheral wall, that is, the inclination of the partition wall with respect to the inflow direction of the exhaust gas is small. Although the pressure loss was 200 mmH 2 or less and the collection rate was 90% or more, the amount of the collection of the erosion resistant carbon powder was 6 g / L, and the erosion resistance was lower than those of Examples 1-5. Moreover, in the comparative example 1, it was confirmed that the vicinity of the plugging part on the exhaust gas outlet side is particularly greatly melted at the carbon trapping amount (8 g / L) where the melt damage occurred.
（実施例６〜７）
実施例６及び７のセラミックハニカムフィルタは、外周壁を形成するためのコート材の水分量を調整して、コート材の粘度を、実施例６では２５０００ｃＰ、実施例７では５００００ｃＰとして外周壁をコートした以外は、実施例２と同様にして作製し、外径２６７ｍｍ、長さ３０５ｍｍ、隔壁の間隔１．５２ｍｍ、隔壁の厚さ０．３ｍｍで、端面と外周壁が略直交し、外周壁が略円筒形状であり、長手方向断面において、隔壁の長手方向端部が外周壁と接する隔壁が２ケ存在し、隔壁の気孔率が６３％、隔壁の表面粗さが最大高さＲyで５５μｍである２種類のセラミックハニカムフィルタを得た。実施例６〜７のセラミックハニカム構造体の、隔壁に沿って切断した２等分割断面において、３本の流路の隔壁間隔を５０ｍｍ間隔で測定したところ、１．４７〜１．５５ｍｍであった。また、一方の端面に直角な曲面に対する他方の端面のずれ量は、最大０．４ｍｍであり、両端面から１２．７ｍｍの位置で等間隔に各４ケ所測定した外径寸法は、２６６〜２６８ｍｍであった。
(Examples 6 to 7)
The ceramic honeycomb filters of Examples 6 and 7 were coated on the outer peripheral wall by adjusting the moisture content of the coating material for forming the outer peripheral wall and setting the viscosity of the coating material to 25000 cP in Example 6 and 50000 cP in Example 7. In the same manner as in Example 2, the outer diameter was 267 mm, the length was 305 mm, the partition wall spacing was 1.52 mm, the partition wall thickness was 0.3 mm, the end face and the outer peripheral wall were substantially orthogonal, and the outer peripheral wall was It has a substantially cylindrical shape, and in the longitudinal section there are two partition walls where the longitudinal end of the partition wall is in contact with the outer peripheral wall, the partition wall porosity is 63%, and the partition wall surface roughness is 55 μm at the maximum height Ry. Two types of ceramic honeycomb filters were obtained. In the equally divided cross section cut along the partition walls of the ceramic honeycomb structures of Examples 6 to 7, the partition wall spacing of the three channels was measured at 50 mm intervals, and was 1.47 to 1.55 mm. . Further, the maximum deviation of the other end face with respect to the curved surface perpendicular to the one end face is 0.4 mm, and the outer diameter measured at four locations at equal intervals from the both end faces is 266 to 268 mm. Met.
実施例６〜７のセラミックハニカムフィルタに対し、実施例１と同様、圧力損失、捕集率、耐溶損カーボン粉捕集量、耐熱衝撃温度を測定した表１に示す。ハニカムフィルタの端面と外周壁が略直交し、該外周壁が略円筒形状であり、前記隔壁の気孔率が６３％、隔壁の表面粗さが最大高さＲyで５５μｍであり、且つ隔壁と略平行な外周壁のうちの一つにおいて、隔壁の長手方向端部が外周壁と接する隔壁を２６ケ存在させるようにしたことから、排気ガスの流入方向に対して隔壁が傾いて形成されているため圧力損失は２００ｍｍＨ２Ｏ以下、捕集率は９０％以上、耐溶損カーボン捕集量も１６ｇ／Ｌ以上であり、実施例２のセラミックハニカムフィルタと同等のフィルタ性能が得られた。 As in Example 1, the ceramic honeycomb filters of Examples 6 to 7 are shown in Table 1 in which the pressure loss, the collection rate, the erosion-resistant carbon powder collection amount, and the thermal shock temperature were measured. The end face of the honeycomb filter and the outer peripheral wall are substantially orthogonal, the outer peripheral wall is substantially cylindrical, the partition wall has a porosity of 63%, the partition wall surface roughness is 55 μm at the maximum height Ry, and is substantially the same as the partition wall. In one of the parallel outer peripheral walls, there are 26 partition walls whose longitudinal ends are in contact with the outer peripheral wall, so that the partition walls are inclined with respect to the inflow direction of the exhaust gas. Therefore, the pressure loss was 200 mmH 2 O or less, the collection rate was 90% or more, and the amount of collection of erosion-resistant carbon was 16 g / L or more, and the filter performance equivalent to the ceramic honeycomb filter of Example 2 was obtained.
また、いずれのセラミックハニカムフィルタも外周壁と端面の交差部は略直角となっており鋭角部が存在せず、外周壁が略円筒形状であることから、金属容器に挿入する際に、外周壁と端面の交差部の破損の問題は発生しなかった。それと共に、最外周に位置する流路が外部との間の隔壁を有しないことによって外部に開口して概略軸方向に延びる凹溝を形成しているセラミックハニカム本体と、前記凹溝を充填している外周壁を構成する部材との間の少なくとも一部に空隙を有していることから、耐熱衝撃温度は実用上問題ないレベルである４５０℃以上の４７５℃及び５７０℃が得られた。但し、実施例６では、空隙を有する凹溝の個数割合が、実施例２に比べて低かったため、耐熱衝撃温度は実施例２の５２５℃に比べて低くなった実施例６では低くなった。一方、実施例７では、空隙を有する凹溝の個数割合が、実施例２に比べて高かった、耐熱衝撃温度は実施例２の５２５℃に比べて高くなった。 Also, in any ceramic honeycomb filter, the intersection between the outer peripheral wall and the end surface is substantially perpendicular, there is no acute angle portion, and the outer peripheral wall has a substantially cylindrical shape. There was no problem of breakage at the intersection of the end face. At the same time, the flow path located on the outermost periphery does not have a partition wall between the outside and the ceramic honeycomb body which is opened to the outside and forms a groove extending in the general axial direction, and the groove is filled. The thermal shock temperature was 475 ° C. and 570 ° C. of 450 ° C. or higher, which is a practically no problem level, because a gap was formed at least partly between the members constituting the outer peripheral wall. However, in Example 6, since the number ratio of the concave grooves having voids was lower than that in Example 2, the thermal shock temperature was lower in Example 6, which was lower than 525 ° C. in Example 2. On the other hand, in Example 7, the ratio of the number of concave grooves having voids was higher than that in Example 2, and the thermal shock temperature was higher than that at 525 ° C. in Example 2.
（実施例８〜１０）
実施例８〜１０のセラミックハニカムフィルタは実施例１〜５と同様にカオリン、タルク、シリカ、水酸化アルミ、アルミナなどの粉末を調整して、質量比で、ＳｉＯ2 ：４７〜５３％、Ａｌ2Ｏ3：３２〜３８％、ＭｇＯ：１２〜１６％及びＣａＯ、Ｎａ2Ｏ 、Ｋ2Ｏ、ＴｉＯ2、Ｆｅ2Ｏ3、ＰｂＯ、Ｐ2Ｏ5などの不可避的に混入する成分を全体で２．５％含むようなコージェライト生成原料粉末を得た後に、メチルセルロースとヒドロキシプロピルメチルセルロース等の成形バインダーとグラファイトからなる造孔剤を添加し、規定量の水を注入して充分な混合、混練を行い、可塑化可能な坏土を作製した。この際、造孔剤の添加量を実施例１〜５に対して変更した。
(Examples 8 to 10)
The ceramic honeycomb filters of Examples 8 to 10 were prepared by adjusting powders such as kaolin, talc, silica, aluminum hydroxide, and alumina in the same manner as in Examples 1 to 5, and in terms of mass ratio, SiO 2 : 47 to 53%, Al 2 O 3 : 32 to 38%, MgO: 12 to 16% and all components inevitably mixed such as CaO, Na 2 O, K 2 O, TiO 2, Fe 2 O 3 , PbO, P 2 O 5 After obtaining a cordierite-producing raw material powder containing 2.5%, a pore-forming agent composed of a molding binder such as methylcellulose and hydroxypropylmethylcellulose and graphite is added, and a predetermined amount of water is injected and mixed sufficiently. Kneading was performed to prepare a plasticized clay. Under the present circumstances, the addition amount of the pore making material was changed with respect to Examples 1-5.
次いで、実施例１と同様の方法で、外径２６７ｍｍ、長さ３０５ｍｍ、隔壁の間隔１．５２ｍｍ、隔壁の厚さ０．３ｍｍで、端面と外周壁が略直交し、外周壁が略円筒形状であり、隔壁に沿って切断した２等分割断面において、隔壁の長手方向端部が外周壁と接する隔壁が２ケ存在し、隔壁の気孔率が５５〜８５％、隔壁の表面粗さが最大高さＲyで２５μｍ〜７５μｍである、実施例８〜１０の３種類のハニカムフィルタを作製した。実施例８〜１０のセラミックハニカム構造体の、隔壁に沿って切断した２等分割断面において、３本の流路の隔壁間隔を５０ｍｍ間隔で測定したところ、１．４９〜１．５５ｍｍであった。また、一方の端面に直角な曲面に対する他方の端面のずれ量は、最大０．７ｍｍであり、両端面から１２．７ｍｍの位置で等間隔に各４ケ所測定した外径寸法は、２６５〜２６９ｍｍであった。 Next, in the same manner as in Example 1, the outer diameter was 267 mm, the length was 305 mm, the partition wall spacing was 1.52 mm, the partition wall thickness was 0.3 mm, the end face and the outer peripheral wall were substantially orthogonal, and the outer peripheral wall was substantially cylindrical. In the bisection section cut along the partition wall, there are two partition walls where the longitudinal end of the partition wall contacts the outer peripheral wall, the partition wall porosity is 55 to 85%, and the partition wall surface roughness is maximum. Three types of honeycomb filters of Examples 8 to 10 having a height Ry of 25 to 75 μm were manufactured. In the bisecting cross section cut along the partition walls of the ceramic honeycomb structures of Examples 8 to 10, the partition wall spacing of the three flow paths was measured at 50 mm intervals, and was 1.49 to 1.55 mm. . In addition, the displacement of the other end face with respect to the curved surface perpendicular to one end face is 0.7 mm at the maximum, and the outer diameter measured at four locations at equal intervals from the both end faces is 265 to 269 mm. Met.
実施例８〜１０のセラミックハニカムフィルタに対し、実施例１と同様、圧力損失、捕集率、耐溶損カーボン粉捕集量を測定した結果を、表１に記した。実施例８〜１０のハニカムフィルタは、ハニカムフィルタの端面と外周壁が略直交し、該外周壁が略円筒形状であり、前記隔壁の気孔率が５５〜８５％、隔壁の表面粗さが最大高さＲyで２５〜７５μｍであり、且つ隔壁に沿って切断した２等分割断面において、隔壁の長手方向端部が外周壁と接する隔壁が２ケ存在し、即ち排気ガスの流入方向に対して隔壁が傾いているため、捕集率は９０％以上、耐溶損カーボン捕集量も１６ｇ／Ｌ以上であった。また、いずれのハニカムフィルタも外周壁と端面の交差部は略直角となっており鋭角部が存在せず、外周壁は略円筒形状であることから、金属容器に挿入する際に、外周壁と端面の交差部の破損の問題は発生せず、且つ空隙を有する凹溝の個数割合が、実施例２と同様の４９％で有ったことから、耐熱衝撃温度は、実用上問題ない４５０℃以上が得られた。 For the ceramic honeycomb filters of Examples 8 to 10, the results of measuring the pressure loss, the collection rate, and the amount of collection of the erosion-resistant carbon powder as in Example 1 are shown in Table 1. In the honeycomb filters of Examples 8 to 10, the end face of the honeycomb filter and the outer peripheral wall are substantially orthogonal, the outer peripheral wall is substantially cylindrical, the partition wall has a porosity of 55 to 85%, and the partition wall has the maximum surface roughness. There are two partition walls whose longitudinal ends are in contact with the outer peripheral wall in the two equally divided sections cut along the partition walls at a height Ry of 25 to 75 μm, that is, with respect to the inflow direction of the exhaust gas. Since the partition walls were tilted, the collection rate was 90% or more, and the amount of erosion-resistant carbon collected was 16 g / L or more. Also, in any of the honeycomb filters, the intersection between the outer peripheral wall and the end face has a substantially right angle, there is no acute angle portion, and the outer peripheral wall has a substantially cylindrical shape. The problem of breakage at the intersection of the end faces did not occur, and the number ratio of the concave grooves having voids was 49% as in Example 2. Therefore, the thermal shock temperature was 450 ° C., which is practically no problem. The above was obtained.
（比較例２）
実施例８〜１０において、添加するグラファイトの量を調整した以外は、実施例８〜１０と同様の方法により、外径２６７ｍｍ、長さ３０５ｍｍ、隔壁の間隔１．５２ｍｍ、隔壁の厚さ０．３ｍｍで、端面と外周壁が略直交し、外周壁が略円筒形状であり、隔壁に沿って切断した２等分割断面において、隔壁の長手方向端部が外周壁と接する隔壁が２ケ存在し、隔壁の気孔率が４５％、隔壁の表面粗さが最大高さＲyで９μｍである、比較例２の２種類のハニカムフィルタを作製した。
(Comparative Example 2)
In Examples 8 to 10, except that the amount of graphite to be added was adjusted, in the same manner as in Examples 8 to 10, the outer diameter was 267 mm, the length was 305 mm, the partition wall spacing was 1.52 mm, and the partition wall thickness was 0. 3 mm, the end face and the outer peripheral wall are substantially orthogonal, the outer peripheral wall is substantially cylindrical, and there are two partition walls in which the longitudinal end of the partition wall is in contact with the outer peripheral wall in a bisection section cut along the partition wall. Two types of honeycomb filters of Comparative Example 2 were produced in which the partition wall porosity was 45% and the partition wall surface roughness was 9 μm at the maximum height Ry.
比較例２のハニカムフィルタに対し、実施例１と同様、圧力損失、捕集率、耐溶損カーボン粉捕集量を測定した結果を、表１に記した。比較例２のハニカムフィルタは、隔壁に沿って切断した２等分割断面において、隔壁の長手方向端部が外周壁と接する隔壁が２ケ存在しているものの、隔壁の表面粗さが最大高さＲyで９μｍであることから、捕集率は９０％以上であったものの、圧力損失は２００ｍｍＨ２Ｏを超え、耐溶損カーボン粉捕集量は６ｇ／Ｌと低い値であった。比較例２においても溶損が発生したカーボン捕集量（８ｇ／Ｌ）では、排気ガス出口側の目封止部付近が特に大きく溶損しているのが確認されたため、隔壁におけるカーボン粉の捕集が効率良く行われず、排気ガス出口側の目封止部にカーボン粉が高濃度で堆積していたことが伺える。 For the honeycomb filter of Comparative Example 2, the results of measuring the pressure loss, the collection rate, and the amount of collection of the erosion-resistant carbon powder as in Example 1 are shown in Table 1. The honeycomb filter of Comparative Example 2 has two partition walls whose longitudinal ends are in contact with the outer peripheral wall in a bisected section cut along the partition wall, but the partition wall surface roughness is the maximum height. Since the Ry was 9 μm, the collection rate was 90% or more, but the pressure loss exceeded 200 mmH 2 O, and the collection amount of the erosion resistant carbon powder was a low value of 6 g / L. In Comparative Example 2 as well, it was confirmed that the vicinity of the plugging portion on the exhaust gas outlet side was greatly damaged at the carbon trapping amount (8 g / L) in which melting damage occurred. It can be seen that collection was not performed efficiently and carbon powder was deposited at a high concentration on the plugging portion on the exhaust gas outlet side.
（実施例１１〜１２）
実施例１〜５と同様の方法により、外径２６７ｍｍ、長さ３０５ｍｍ、隔壁の間隔１．５２ｍｍ、隔壁の厚さ０．３ｍｍで、端面と外周壁が略直交し、外周壁が略円筒形状であり、隔壁の気孔率が６３％、隔壁の表面粗さが最大高さＲyで５５μｍであり、、隔壁に沿って切断した２等分割断面に、隔壁の長手方向端部が外周壁と接する隔壁を２及び４ケ存在するようにした、実施例１１及び１２のセラミックハニカムフィルタを作成した。ここで、外周壁コート材をコート後の乾燥条件は、８０℃に加熱した乾燥炉に直接投入し、１２時間保持して行った。実施例１１〜１２のセラミックハニカム構造体の、隔壁に沿って切断した２等分割断面において、３本の流路の隔壁間隔を５０ｍｍ間隔で測定したところ、１．４９〜１．５４ｍｍであった。また、一方の端面に直角な曲面に対する他方の端面のずれ量は、最大０．５ｍｍであり、両端面から１２．７ｍｍの位置で等間隔に各４ケ所測定した外径寸法は、２６５〜２６９ｍｍであった。
(Examples 11 to 12)
In the same manner as in Examples 1 to 5, the outer diameter is 267 mm, the length is 305 mm, the partition interval is 1.52 mm, the partition wall thickness is 0.3 mm, the end face and the outer peripheral wall are substantially orthogonal, and the outer peripheral wall is substantially cylindrical. The partition wall porosity is 63%, the partition wall surface roughness is 55 μm at the maximum height Ry, and the longitudinal end of the partition wall is in contact with the outer peripheral wall in a bisected section cut along the partition wall. Ceramic honeycomb filters of Examples 11 and 12 having 2 and 4 partition walls were prepared. Here, the drying conditions after coating the outer peripheral wall coating material were directly put into a drying furnace heated to 80 ° C. and held for 12 hours. In the equally divided cross section cut along the partition walls of the ceramic honeycomb structures of Examples 11 to 12, the partition wall spacing of the three channels was measured at 50 mm intervals, and was 1.49 to 1.54 mm. . In addition, the displacement of the other end face with respect to the curved surface perpendicular to one end face is 0.5 mm at the maximum, and the outer diameter measured at four positions at equal intervals from the both end faces is 265 to 269 mm. Met.
これらに対して、実施例１と同様に、圧力損失、捕集量、耐溶損カーボン捕集量、耐熱衝撃温度を測定した結果を表２に示す。更に、溶損試験終了後のセラミックハニカムフィルタを切断し、外周壁と外周壁に接する隔壁のなす傾きの角度を測定した結果についても表２に示す。この実施例では、図３及び図５に示すように、隔壁は一方向に傾いた形態であった。ここで、隔壁に沿って切断した２等分割断面において、外周壁と外周壁に接する隔壁のなす角度の測定は、隔壁の長手方向端部が隔壁と接している隔壁で行い、更に当該隔壁が複数有るためこれらの平均値を表２に記した。 On the other hand, the results of measuring the pressure loss, the collected amount, the erosion resistant carbon collected amount, and the thermal shock temperature as in Example 1 are shown in Table 2. Further, Table 2 shows the results of cutting the ceramic honeycomb filter after the end of the erosion test and measuring the inclination angle between the outer peripheral wall and the partition wall contacting the outer peripheral wall. In this embodiment, as shown in FIGS. 3 and 5, the partition wall was inclined in one direction. Here, in the bisection section cut along the partition wall, the angle formed between the outer peripheral wall and the partition wall in contact with the outer peripheral wall is measured at the partition wall whose longitudinal end is in contact with the partition wall. Since there are a plurality of these, the average values are shown in Table 2.
実施例１１及び１２のセラミックハニカムフィルタは、隔壁に沿って切断した２等分割断面において、隔壁の長手方向端部が外周壁と接する隔壁が１〜６ケの範囲内であり、且つ、長手方向断面における外周壁と隔壁の傾きが０．３〜３．３°の範囲内であることから、排気ガスの流入方向に対して隔壁が傾いて形成されているため圧力損失は２００ｍｍＨ２Ｏ以下、捕集率は９０％以上、耐溶損カーボン捕集量も１６ｇ／Ｌ以上であった。特に、隔壁に沿って切断した２等分割断面における外周壁と隔壁の傾きの大きい方が、耐溶損カーボン捕集量が大きくなっている。 In the ceramic honeycomb filters of Examples 11 and 12, in the bisection section cut along the partition walls, the partition walls are in the range of 1 to 6 partition walls where the longitudinal ends of the partition walls are in contact with the outer peripheral wall, and in the longitudinal direction. Since the inclination of the outer peripheral wall and the partition wall in the cross section is within the range of 0.3 to 3.3 °, the pressure loss is 200 mmH 2 O or less because the partition wall is inclined with respect to the exhaust gas inflow direction. The collection rate was 90% or more, and the amount of corrosion-resistant carbon collected was 16 g / L or more. In particular, the larger the inclination of the outer peripheral wall and the partition wall in the bisected section cut along the partition wall, the larger the amount of sequestering carbon captured.
また、いずれのハニカムフィルタも外周壁と端面の交差部は略直角となっており鋭角部が存在せず、外周壁が略円筒形状であることから、金属容器に挿入する際に、外周壁と端面の交差部の破損の問題は発生しなかった。それと共に、最外周に位置する流路が外部との間の隔壁を有しないことによって外部に開口して概略軸方向に延びる凹溝を形成しているセラミックハニカム本体と、前記凹溝を充填している外周壁を構成する部材との間の少なくとも一部に空隙を有しており、且つ、外周壁の外表面に開口した空隙部を有していることから、耐熱衝撃温度は実用上問題ないレベルである４５０℃以上の５００〜５７５℃が得られた。 Also, in any of the honeycomb filters, the intersection between the outer peripheral wall and the end face has a substantially right angle, there is no acute angle portion, and the outer peripheral wall has a substantially cylindrical shape. The problem of breakage at the intersection of the end faces did not occur. At the same time, the flow path located on the outermost periphery does not have a partition wall between the outside and the ceramic honeycomb body which is opened to the outside and forms a groove extending in the general axial direction, and the groove is filled. The thermal shock temperature is a practical problem because it has a gap in at least a part of the member constituting the outer peripheral wall and an opening in the outer surface of the outer peripheral wall. An unprecedented level of 500 to 575 ° C., which is 450 ° C. or higher, was obtained.
（実施例１３〜１４）
実施例１と同様に、カオリン、タルク、シリカ、水酸化アルミ、アルミナなどの粉末を調整して、質量比で、ＳｉＯ2 ：４７〜５３％、Ａｌ2Ｏ3：３２〜３８％、ＭｇＯ：１２〜１６％及びＣａＯ、Ｎａ2Ｏ 、Ｋ2Ｏ、ＴｉＯ2、Ｆｅ2Ｏ3、ＰｂＯ、Ｐ2Ｏ5などの不可避的に混入する成分を全体で２．５％含むようなコージェライト生成原料粉末を得た後に、メチルセルロースとヒドロキシプロピルメチルセルロース等の成形バインダーとグラファイトからなる造孔剤を添加し、規定量の水を注入して充分な混合、混練を行い、可塑化可能な坏土を作製した。
(Examples 13 to 14)
In the same manner as in Example 1, powders such as kaolin, talc, silica, aluminum hydroxide, and alumina were prepared, and by mass ratio, SiO 2 : 47 to 53%, Al 2 O 3 : 32 to 38%, MgO: 12 to 16% and CaO, Na 2 O, K 2 O, TiO 2, Fe 2 O 3, PbO, inevitably cordierite generation such as those containing 2.5% throughout the components to be mixed, such as P 2 O 5 After obtaining the raw material powder, a pore forming agent made of graphite and molding binders such as methylcellulose and hydroxypropylmethylcellulose and graphite is added, and a prescribed amount of water is injected, and sufficient mixing and kneading are performed to form a plasticizable clay. Produced.
次に、図１０に示すような押出成形機に、公知の構造の押出成形用金型を装着し、ハニカム構造の成形体を重力方向に押し出す際に、ハニカム成形体の重力を支えるために重力の反対方向に付加する保持力の大きさ及び方向を変化させ、隔壁が長手方向に対して湾曲した、ハニカム構造の成形体を得た。その後、外周部及び両端面を加工除去した後、公知の方法で目封止部を形成して焼成した上で、外径２６４ｍｍ、長さ３０５ｍｍ、隔壁の間隔１．５２ｍｍ、隔壁の厚さ０．３ｍｍで隔壁の気孔率が６３％、隔壁の表面粗さが最大高さＲyで５５μｍであり、外周に対し傾きを有し、且つ最外周に位置する流路が外部との間に隔壁を有しないことによって、外部に開口して軸方向に延びる凹溝を形成しているセラミックハニカム本体を作製した。一方、外周壁のコート材として、平均粒径１０μｍのコージェライト粉末Ｂ１００、質量部に対して、コロイダルシリカを固形分で１２質量部配合し、これにメチルセルロース、水を加えて混練し、粘度３２０００ｃＰのコート材を準備した。次いで、前記準備した外周に凹溝を有するハニカム本体の外周部に塗布した上で、７０℃で１２時間乾燥させた。その後４５０℃まで加熱して、前記メチルセルロースを分解すると共に、凹溝と外周壁が強固に一体化された外径２６７ｍｍ、長さ３０５ｍｍ、隔壁の間隔１．５２ｍｍ、隔壁の厚さ０．３ｍｍで、端面と外周壁が略直交し、外周壁が略円筒形状であり、長手方向断面において外周壁に対して隔壁が傾いている図７〜図８に示す形態の実施例１３及び１４のセラミックハニカムフィルタを作製した。実施例１３〜１４のセラミックハニカム構造体の、隔壁に沿って切断した２等分割断面において、３本の流路の隔壁間隔を５０ｍｍ間隔で測定したところ、１．４８〜１．５６ｍｍであった。また、一方の端面に直角な曲面に対する他方の端面のずれ量は、最大０．７ｍｍであり、両端面から１２．７ｍｍの位置で等間隔に各４ケ所測定した外径寸法は、２６６〜２６９ｍｍであった。 Next, when an extrusion mold having a known structure is mounted on an extrusion molding machine as shown in FIG. 10 and the honeycomb structure is extruded in the direction of gravity, gravity is applied to support the gravity of the honeycomb structure. The size and direction of the holding force applied in the opposite direction were changed to obtain a formed article having a honeycomb structure in which the partition walls were curved with respect to the longitudinal direction. Then, after processing and removing the outer peripheral portion and both end faces, a plugging portion is formed and fired by a known method, and then the outer diameter is 264 mm, the length is 305 mm, the partition wall spacing is 1.52 mm, and the partition wall thickness is 0. The partition wall porosity is 63% at 3 mm, the surface roughness of the partition wall is 55 μm at the maximum height Ry, and the partition wall is inclined with respect to the outer periphery and the channel located on the outermost periphery is connected to the outside. By not having it, a ceramic honeycomb body having a groove that opens to the outside and extends in the axial direction was produced. On the other hand, as a coating material for the outer peripheral wall, 12 parts by mass of colloidal silica in a solid content is blended with 10 parts by mass of cordierite powder B100 having an average particle diameter of 10 μm, and kneaded with adding methylcellulose and water to a viscosity of 32000 cP. A coating material was prepared. Subsequently, after apply | coating to the outer peripheral part of the honeycomb main body which has a groove in the prepared outer periphery, it was dried at 70 degreeC for 12 hours. Thereafter, the mixture was heated to 450 ° C. to decompose the methylcellulose, and the outer diameter wall was 267 mm, the length was 305 mm, the partition interval was 1.52 mm, and the partition wall thickness was 0.3 mm. The ceramic honeycombs of Examples 13 and 14 in the form shown in FIGS. 7 to 8 in which the end face and the outer peripheral wall are substantially orthogonal, the outer peripheral wall is substantially cylindrical, and the partition walls are inclined with respect to the outer peripheral wall in the longitudinal section. A filter was produced. In the bisecting cross section cut along the partition walls of the ceramic honeycomb structures of Examples 13 to 14, the partition wall spacing of the three flow paths was measured at 50 mm intervals, and was 1.48 to 1.56 mm. . Also, the maximum deviation of the other end face with respect to the curved surface perpendicular to one end face is 0.7 mm, and the outer diameter measured at four locations at equal intervals from the both end faces is 266 to 269 mm. Met.
これら実施例１３及び１４のセラミックハニカムフィルタに対して、実施例１と同様に、圧力損失、捕集量、耐溶損カーボン捕集量、耐熱衝撃温度を測定した結果を表３に示す。更に、溶損試験終了後のハニカムフィルタを切断し、外周壁と外周壁に接する隔壁のなす傾きの角度を測定した結果についても表３に示す。 For these ceramic honeycomb filters of Examples 13 and 14, the results of measurement of pressure loss, collection amount, resistance to erosion carbon, and thermal shock temperature are shown in Table 3 as in Example 1. Furthermore, Table 3 also shows the results of cutting the honeycomb filter after the end of the erosion test and measuring the inclination angle between the outer peripheral wall and the partition wall contacting the outer peripheral wall.
実施例１３及び１４のセラミックハニカムフィルタは、隔壁に沿って切断した２分割断面において、隔壁の長手方向端部が外周壁と接する隔壁が１〜６ケの範囲内であり、且つ、長手方向断面における外周壁と隔壁の傾きが０．３〜３．３°の範囲内であることから、排気ガスの流入方向に対して隔壁が傾いて形成されているため圧力損失は２００ｍｍＨ２Ｏ以下、捕集率は９０％以上、耐溶損カーボン捕集量も１６ｇ／Ｌ以上であった。特に、実施例１及び２のセラミックハニカムフィルタが図３に示すように、外周壁に対して隔壁が略一様に傾いているのに比べて、実施例１３及び１４のセラミックハニカムフィルタは、図７に示すように外周壁に対して隔壁が湾曲していることから、耐溶損カーボン捕集量が大きくなっている。 In the ceramic honeycomb filters of Examples 13 and 14, in the two-divided cross section cut along the partition wall, the partition wall in the longitudinal direction end portion is in the range of 1 to 6 and the longitudinal cross section is in contact with the outer peripheral wall. Since the inclination of the outer peripheral wall and the partition wall is within a range of 0.3 to 3.3 °, the partition wall is inclined with respect to the exhaust gas inflow direction, so that the pressure loss is 200 mmH 2 O or less. The collection rate was 90% or more, and the amount of corrosion-resistant carbon trapped was 16 g / L or more. In particular, as shown in FIG. 3, the ceramic honeycomb filters of Examples 13 and 14 are substantially the same as those of Examples 13 and 14, as shown in FIG. Since the partition wall is curved with respect to the outer peripheral wall as shown in FIG.
また、いずれのハニカムフィルタも外周壁と端面の交差部は略直角となっており鋭角部が存在せず、外周壁が略円筒形状であることから、金属容器に挿入する際に、外周壁と端面の交差部の破損の問題は発生しなかった。それとともに、最外周に位置する流路が外部との間の隔壁を有しないことによって外部に開口して概略軸方向に延びる凹溝を形成しているセラミックハニカム本体と、前記凹溝を充填している外周壁を構成する部材との間の少なくとも一部に空隙を有しており、且つ、外周壁の外表面に開口した空隙を有していることから、耐熱衝撃温度は実用上問題ないレベルである４５０℃以上の５５０℃が得られた。 Also, in any of the honeycomb filters, the intersection between the outer peripheral wall and the end face has a substantially right angle, there is no acute angle portion, and the outer peripheral wall has a substantially cylindrical shape. The problem of breakage at the intersection of the end faces did not occur. At the same time, the flow path located on the outermost periphery does not have a partition wall between the outside and the ceramic honeycomb body which is opened to the outside and forms a groove extending substantially in the axial direction, and the groove is filled. The thermal shock temperature is practically no problem because it has a gap in at least a part between the members constituting the outer peripheral wall and an opening in the outer surface of the outer peripheral wall. A level of 550 ° C. above 450 ° C. was obtained.
以上、実施例を用いて説明したように、本発明例のセラミックハニカムフィルタの場合には、外周壁に対してセル壁長手方向が傾いているので、カーボン粉の局部的な堆積が起こりにくいため、ハニカムフィルタの隔壁が外周壁と平行の場合に比べて、溶損発生までのカーボン粉の捕集量が多いことが判る。 As described above with reference to the examples, in the case of the ceramic honeycomb filter of the example of the present invention, since the cell wall longitudinal direction is inclined with respect to the outer peripheral wall, local deposition of carbon powder hardly occurs. It can be seen that the amount of carbon powder collected until the occurrence of melting damage is larger than when the partition walls of the honeycomb filter are parallel to the outer peripheral wall.
１；セラミックハニカム構造体
１ａ；入口側目封止部
１ｂ；出口側目封止部
２ａ；入口側排気ガス
２ｂ；出口側排気ガス
１０；セラミックハニカムフィルタ
１０ａ；入口側端面
１０ｂ；出口側端面
１１ａ；外周壁
１１ｂ；隔壁
１１ｂ−ｔ；隔壁の長手方向端部
１２；収納容器
１３ａ、１３ｂ；把持部材
１４；把持部材
１５；流路
１５ａ；入口側流路
１５ｂ；出口側流路
１６；堆積した微粒子
１７；隔壁に沿って切断した２分割断面の切断箇所
１８；凹溝
１９；セラミックハニカム本体
２１；押出し成形機
２２；口金
２３；支持手段
３１ｂ；隔壁
３１ｃ；流路
３５；除去加工される外周部
３６；除去加工後の外周面
３７；除去加工される両端部
３８；除去加工後の両端面
３９；目封止材
４１：外周壁の外表面に開口した空隙
４２；外周壁を構成する部材と凹溝の間に形成された空隙
５１、５４；凹溝を構成する隔壁の端部
５２、５３；凹溝を構成する隔壁の交点
５５、５６、５７、５８；凹溝断面における外周壁を構成する部材と隔壁の交点
DESCRIPTION OF SYMBOLS 1; Ceramic honeycomb structure 1a; Inlet side plugging part 1b; Outlet side plugging part 2a; Inlet side exhaust gas 2b; Outlet side exhaust gas 10; Ceramic honeycomb filter 10a; Inlet side end face 10b; An outer peripheral wall 11b; a partition wall 11b-t; a longitudinal end 12 of the partition wall; a storage container 13a, 13b; a gripping member 14; a gripping member 15; a channel 15a; an inlet side channel 15b; Fine particle 17; cut portion 18 of two-divided cross section cut along partition wall; concave groove 19; ceramic honeycomb body 21; extrusion molding machine 22; die 23; support means 31b; partition wall 31c; Portion 36; outer peripheral surface 37 after removal processing; both end portions 38 to be removed; both end surfaces 39 after removal processing; plugging material 41: gap 42 opened on the outer surface of the outer peripheral wall; Gaps 51 and 54 formed between the member to be formed and the groove; end portions 52 and 53 of the partition walls forming the groove; intersections 55, 56, 57 and 58 of the partition walls forming the groove; Intersections between members that make up the outer wall and the bulkhead
Claims (9)
9. The ceramic honeycomb structure according to claim 8, wherein the total length of the voids opened in the outer surface is one time or more of the entire length of the ceramic honeycomb structure.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2004030688A JP3611213B2 (en) | 2003-02-07 | 2004-02-06 | Ceramic honeycomb structure |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2003031462 | 2003-02-07 | ||
| JP2004030688A JP3611213B2 (en) | 2003-02-07 | 2004-02-06 | Ceramic honeycomb structure |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2004255377A JP2004255377A (en) | 2004-09-16 |
| JP3611213B2 true JP3611213B2 (en) | 2005-01-19 |
Family
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2004030688A Expired - Lifetime JP3611213B2 (en) | 2003-02-07 | 2004-02-06 | Ceramic honeycomb structure |
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| Country | Link |
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| JP (1) | JP3611213B2 (en) |
Families Citing this family (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7566487B2 (en) * | 2004-07-07 | 2009-07-28 | Jonathan Jay Feinstein | Reactor with primary and secondary channels |
| JP4505579B2 (en) * | 2004-09-03 | 2010-07-21 | 独立行政法人産業技術総合研究所 | Exhaust gas purification structure and manufacturing method thereof |
| JP2006231475A (en) * | 2005-02-25 | 2006-09-07 | Hitachi Metals Ltd | Method of machining ceramic honeycomb structure, and device for machining the same |
| FR2886869B1 (en) * | 2005-06-14 | 2007-08-31 | Saint Gobain Ct Recherches | STRUCTURE AND CATALYTIC FILTER FOR FILTERING GAS COMPRISING HYDROPHOBIC OR OLEOPHOBIC CEMENT |
| WO2006137151A1 (en) * | 2005-06-24 | 2006-12-28 | Ibiden Co., Ltd. | Honeycomb structure and exhaust gas purifier |
| JP5230903B2 (en) * | 2006-02-06 | 2013-07-10 | 東京窯業株式会社 | Setter for firing |
| CN101346184B (en) * | 2006-07-03 | 2012-07-11 | 日本碍子株式会社 | Honeycomb structure and method for manufacturing the same |
| JP2011177893A (en) * | 2008-06-30 | 2011-09-15 | Hitachi Metals Ltd | Method of manufacturing ceramic honeycomb molded body |
| KR101028548B1 (en) * | 2008-09-05 | 2011-04-11 | 기아자동차주식회사 | A device for purifying exhaust gas |
| JP2012206080A (en) * | 2011-03-30 | 2012-10-25 | Ngk Insulators Ltd | Honeycomb filter |
| JP2013039513A (en) * | 2011-08-12 | 2013-02-28 | Sumitomo Chemical Co Ltd | Honeycomb filter |
| JP2014148924A (en) * | 2013-01-31 | 2014-08-21 | Ngk Insulators Ltd | Exhaust gas purification device |
| DE102017124225A1 (en) * | 2017-10-18 | 2019-04-18 | Man Diesel & Turbo Se | Exhaust after-treatment system and exhaust aftertreatment process |
| CN109990472B (en) * | 2018-01-02 | 2024-03-15 | 芜湖美的厨卫电器制造有限公司 | Inner container for phase-change water heater and phase-change water heater with same |
| CN112678913B (en) * | 2020-12-02 | 2023-10-27 | 南京丰禾新材料科技有限公司 | Pig raising wastewater filtering equipment capable of regenerating filter materials by microwaves |
| CN116848366A (en) * | 2021-03-11 | 2023-10-03 | 日本碍子株式会社 | Heat exchange member, heat exchanger using the heat exchange member, and method for manufacturing the heat exchange member |
-
2004
- 2004-02-06 JP JP2004030688A patent/JP3611213B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JP2004255377A (en) | 2004-09-16 |
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