DE102007000475A1 - Production of an exhaust gas cleaning filter used for collecting particles in an exhaust gas comprises producing a honeycomb body, applying a mask material to the ends of the body, immersing the ends in a binder solution and drying - Google Patents

Abstract

Production of an exhaust gas cleaning filter (1) comprises producing a honeycomb body having an outer peripheral wall (11), separating walls (2) and cells (3), applying a mask material to the ends (13, 14) of the honeycomb body to form through-holes in regions corresponding the cells ends, immersing the ends of the honeycomb body in a binder solution and drying the body, immersing the ends of the body in a slurry-like plugging material to plug the cell ends and firing the body together with the plugged sections. Independent claims are also included for the following: (1) Plugging slurry used in the above process; and (2) Method for the production of an exhaust gas cleaning filter.

Description

1. Technical field of invention

The The present invention relates to a method of manufacturing an exhaust gas purification filter for trapping in exhaust gases Particles to thereby clean the exhaust gases, the exhaust gases from be delivered to an internal combustion engine.

2. Description of the related state of the technique

In a modern motor vehicle powered by an internal combustion engine is driven, so far an attempt has been made, a ceramic honeycomb structural body to apply as an exhaust gas purifying filter to in from the internal combustion engine captured exhaust gases contained particles to thereby to clean the exhaust gases.

Like this in the 22 and 23 is shown, the ceramic honeycomb structural body 9 an outer peripheral wall 91 , Partitions 92 inside the outer perimeter wall 91 are formed in a honeycomb structure, and a plurality of cells 95 on, passing through the dividing walls 92 are divided and extending to both end surfaces 93 and 94 extend. Furthermore, in order to increase the cleaning efficiency, the ceramic honeycomb structural body has 9 constipation sections 96 (see also the Japanese Patent Application Publication No. 2004-154 768 ).

When the clogging sections 96 generally have the cells 95 of the ceramic honeycomb structural body 9 first cell ends 95a sealed with a plugging material that is a material of the plugging sections 95 forms, and second cell ends 95b that stay open. Then, the ceramic honeycomb structural body 9 and the clogging material that ends at the first cell ends 95a Sealed, burned to obtain a finished product.

Like this in 18 are shown, in particular masking tapes 97 initially at the end surfaces 93 and 94 appropriate. Like this in 19 is shown, then a high-density energy such as a laser beam on the Maskierbänder 97 so blasted that perforated sections 975 be formed in the areas that the first cell ends 95a sealed with the clogging material, while leaving covered areas which are the second cell ends 95 which are not closed with the clogging material.

After that, as in the 20 and 21 shown is the end pages 93 and 94 of the ceramic honeycomb structural body 9 alternately in slime-like, clogging material 99a immersed in a container 99 is filled. In this process, slime-like, clogging material enters the first cell ends 95a on each end side of the ceramic honeycomb structural body 9 over the perforated sections 975 to the first cell ends 95a with the slime-like, clogging material to clog. Subsequently, the ceramic honeycomb structural body 9 , whose first cell ends 95a sealed with the slime-like, clogging material, fired. This will allow the clogged sections 96 in the first cell ends 95a of the ceramic honeycomb structural body 9 be formed in a way like this in the 21 and 22 is shown.

However, in the manufacturing process of this prior art, there has been the occurrence of a lower affinity between the clogging material 99a and a cell wall 92 a problem when the end faces 93 and 94 of the ceramic honeycomb structural body 9 in a slime-like, clogging material 99a be dived (see 21 ). Like this in 24 is shown, therefore, there is a risk of clogging gap (gap) 90 which by nature is between the cell wall 92 and a surface 96a the clogged section 62 is produced. When under such a defective condition, the ceramic honeycomb structural body 9 As an exhaust gas purifying filter, the exhaust gases may leak out of the filter without capturing the particulates. Thus, there has been a problem that a reliable cleaning of the exhaust gases is made difficult.

also was it is a common practice in producing the ceramic honeycomb structural body; a ceramic honeycomb compact by an extrusion molding or to make a piston forming. When forming the compact piece through Extrusion forming becomes a kneaded raw material for extrusion molding exposed using a mold to form a compact piece, which in turn is dried and fired to supply the ceramic honeycomb structural body receive.

Of Further, the ceramic honeycomb structural body usually has cell ends, from a part is closed with clogged sections. At the Producing such a ceramic honeycomb structural body, the has the clogged portions becomes kneaded raw material subjected to extrusion molding using a mold a compact piece which, in turn, is dried, temporarily fired, masked is clogged and burned, to the ceramic honeycomb body receive.

At the Clogging of the ceramic honeycomb structural body with the clogging Material will be cell ends, each surrounded by cell walls are, of the ceramic honeycomb body with the clogging Material clogged. In the prior art, there was a difficulty the cell ends of the ceramic honeycomb structural body in a desired Depth to clog without any gap or gap is generated between the plugging material and the cell wall.

SUMMARY OF THE INVENTION

The The present invention addresses the problems set forth above and their job is to have an exhaust gas purification filter, a procedure for manufacturing the exhaust gas purification filter, which has increased connectivity between a cell wall and a clogged portion can, and a clogging mud for one Use in a method of manufacturing the exhaust gas purification filter to make it possible is, the cell ends of the exhaust gas purification filter at a predetermined Constipation depth with an increased thermal shock resistance to clog.

Around to solve the above stated problem, creates a first aspect of the present invention, a method of manufacturing an exhaust gas purification filter for trapping in an exhaust gas produced by an internal combustion engine is discharged, contained particles, thereby to purify the exhaust gas, with the following steps: a honeycomb preparatory step for preparing a ceramic honeycomb structural body, an outer peripheral wall, partitions, the inside of the outer peripheral wall be formed in a honeycomb pattern and serve as cell walls, and has a variety of cells passing through the partitions are separated and extend to both end sides of the honeycomb structural body and the first cell ends being clogged and second cell ends that are not clogged; a masking step for Applying a masking material on both end sides of the honeycomb structural body to penetrate through holes form the areas corresponding to the first cell ends, which are clogged with constipation sections while the other remaining areas are covered, the second cell ends that are not clogged; a pretreatment step, a step of immersing the both end sides of the honeycomb structural body in a binder solution, in the water-soluble Binders dissolved in water is, in a water-repellent or in a hydrophobic treatment agent, and for drying the honeycomb structural body having; a plugging material application step for dipping the two End sides of the honeycomb structural body, exposed to the masking step and pretreatment step into a slutty Blockage material acting as a material of the plugging sections acts, such that the first cell ends with the Verstopfungsabschnitten be clogged; and a firing step for firing the honeycomb structural body with the blockage sections that are in the first cell ends are located.

at the manufacturing method of the first aspect according to the present invention The most important point in the fact that the pretreatment step sits before the step of applying or applying the clogging Materials executed becomes.

Specifically, prior to carrying out the step of applying the clogging material, the two end surfaces or end faces of the ceramic honeycomb structural body in the binder solution containing water in which the water-soluble binder is dissolved are immersed in the water-repellent or in the hydrophobic treatment agent, after which ceramic honeycomb structural body (in the pretreatment step) is dried. In this process, when the binder solution is applied, the binder solution enters the cells of the ceramic honeycomb body via its end portions at the end faces. This allows the water-soluble binder to adhere to the partition walls at least in the areas located near the end surfaces. Therefore, when the step of applying the clogging material is carried out, the water-soluble binder adhering to the partition walls causes increased affinity between the clogging material and the partition walls, allowing the clogging material and the partition walls to be improved in bonding ability (FIG. Binding ability). As a result, when the ceramic honeycomb structural body and the plugged-end plugged portions are fired, there is no gap or gap between the clogged portions and the partition walls of the ceramic honeycomb structural body.

If the water repellent or the hydrophobic treatment agent is applied, the water repellent or the hydrophobic Treatment agent on the partitions of the ceramic honeycomb structural body be coated at least in the areas that are near the end faces are located. Therefore, it will be for the partitions difficult to absorb the water content that is in the clogging Material is located. This will cause the occurrence of a reduction the volume of clogging material that clogs the cell ends, suppressed which is effected by the water content of the clogging material through the partitions is absorbed. As a result, upon firing of the ceramic Honeycomb structural body no gap between the clogged sections and the partitions of the ceramic honeycomb structural body.

consequently allows the present invention provides an exhaust gas purification filter, the increased connectivity (Binding ability) between the partitions and the clogged sections.

One second aspect of the present invention provides an exhaust gas purification filter, by the method of manufacturing an exhaust gas purification filter according to the present Invention is produced.

at The second aspect of the present invention is an exhaust gas purification filter created by the method of manufacturing an exhaust gas purification filter according to the first Aspect of the present invention is produced. In the exhaust gas purification filter can be avoided that a gap between the clogged sections and the partitions while the manufacturing process is generated. Therefore, the exhaust gas purification filter has an increased connectivity (Binding ability) between the clogged sections and the partitions. Accordingly, the Exhaust gas purification filter of the second aspect of the present invention to be able to prevent exhaust gases from the exhaust gas purification filter across a gap between the clogged sections and the partitions, what makes it possible the exhaust gases in an extraordinary reliable Way to clean.

One Third aspect of the present invention provides a clogging sludges for one Use in a method for producing an exhaust gas purification filter, which consists of a honeycomb structural body, an outer peripheral wall, Cell walls the inside of the outer peripheral wall are formed in a honeycomb pattern, and a large number at square-shaped cells separated by the cell walls are and extend to both end sides of the ceramic honeycomb structural body, having first cell ends which become plugged, and has second cell ends that are not clogged with the obstructive sludges Comprising at least aggregates, a dispersant and Water; the aggregates containing ceramic powder, the cordierite crystals on firing give off and that has an average particle diameter, from 6 to 22 μm (according to the standard: D50) is enough; and wherein the clogging slurry to the cell walls each attached at a contact angle of less than about 114 ° is.

Of the most important point in the third aspect of the present invention includes the clogging mud for one Use when clogging a section or part of the quadrangular shaped cells of the honeycomb structural body, which as an essential Contains component elements, which have a ceramic powder that burns cordierite crystals emits. The ceramic powder has an average particle diameter size, the from 6 to 22 μm enough, and the clogging slurry will be on the cell walls respectively attached at a contact angle with a size of less than about 114 °.

By the application of such a clogging slurry, the Cell ends of the honeycomb structural body with the clogging mud in a uniform given depth are clogged without leaving any gap between the clogged portion and the associated cell wall is caused thereby allows is that the honeycomb body an increased thermal shock resistance having.

The is called, by using the aggregates containing ceramic powder, while burning cordierite crystals can give up the clogging mud and the cell ends of the honeycomb structural body with each other increased reliability be connected when burning. In addition, there is no difference in the thermal expansion between the clogging slurry and the cell ends of the honeycomb structural body, which makes it possible the honeycomb structural body to get that has the clogged sections with this at an elevated thermal shock resistance (Thermal shock resistance) are connected.

Furthermore allows the use of ceramic powder that is selected that there is an average particle diameter in a range of values from 6 to 22 μm (according to the norm: D50), suppressing the occurrence of a contraction due to crystallization of the aggregates when the clogging sludges is subjected to the step of burning. At this moment results there is a smaller difference in a rate of contraction of the aggregates while the step of burning, thereby preventing a gap between the clogged portion and the associated cell wall at a stage is generated, following the step of applying the clogging Materials connects.

In addition, refers In the following application, the term "after the Norm: D50 "on one Standard for defining a distribution range into which a value of 50 of a lower frequency falls on particle distribution, which is determined as "D50" and which belongs to the scattering area. The "after the standard: D50 "at of the present invention 14 ± 8 μm.

Of Further, the clogging mud is attached to the cell walls respectively attached at a contact angle with a size of less than about 114 °. This makes possible, that the cell ends of the honeycomb structural body with the clogging sludges be plugged without any gap or gap between the cell wall and the clogged portion is generated.

The is called in the third aspect of the present invention, the honeycomb structural body includes the clogging mud has been applied to the cells, each one quadrangular Shape in which each corner is angled at 90 °. The clogging sludges which is attached to the cell wall, has a contact angle with a size of less as about 114 °, while he has a suitable wetting property. Therefore, the clogging sludges penetrate at the four corners of each cell, which makes it possible that the clogging mud causes blockage in the cell ends without a gap is generated between the clogged portion and the associated cell wall.

Consequently the present invention is capable of clogging sludges to create, which consists of limited essential components, wherein the average particle diameter in a given Range is specified while the contact angle of the clogging slurry is specified, thereby when the cells of the honeycomb structural body with the clogging sludges The clogging muds clog the cell ends in one uniform, predetermined blockage depth can clog without any Gap created between the clogged portion and the cell wall will, what an increase of thermal shock resistance (Thermal shock resistance) leads.

One Fourth aspect of the present invention provides a method for manufacturing an exhaust gas purification filter, which consists of a honeycomb structural body, an outer peripheral wall, porous Cell walls, the inside the outer peripheral wall are formed in a honeycomb pattern, and a large number has square shaped cells separated by the cell walls are up to both end sides of the ceramic honeycomb structural body in extend its axial direction, the first cell ends, with a clogging mud to be plugged, which consists of a cordierite mixed composition, and having second cell ends that are not clogged, wherein the Method characterized by the following steps: extrusion molding for molding a compact honeycomb body with a base material in a honeycomb structure by extrusion molding, drying the compact Honeycomb body, Cutting the compact honeycomb body in a given length with a structure in which the cell walls are formed in the honeycomb pattern are and the big one Number of square-shaped cells separated by the cell walls are and extend to both end surfaces; pre-baking the compact honeycomb body, around a honeycomb body form; Masking for applying a masking material both end sides of the honeycomb body, around through holes in the areas corresponding to the first cell ends, and covered sections in the other areas that form the correspond to second cell ends; Clogging to apply clogging sludges at the first cell ends of the honeycomb body via the through holes, the have been formed in the masking material; Burning the honeycomb body and the Clogging material that has been stuffed into the first cell ends is, in a simultaneous way; and further that the plugging slurry of claim 9 to 13 is used as the clogging slurry, with the the honeycomb body is clogged.

In the method for manufacturing an exhaust gas purification filter of the fourth aspect of the present invention, in producing the exhaust gas purification filter, the plugging slurry of the third aspect of the present invention is used as the plugging slurry. This allows the honeycomb structural body to have cell ends that are clogged with a uniform plugging depth without creating any gap between the plugged portion and the associated cell wall while there is an increased thermal shock resistance.

at the method of manufacturing an exhaust gas purification filter of the fourth Aspect of the present invention is contraction (contraction) of the honeycomb structural body usually at a stage to run a Vorbrennschritts completed. As described above is possible the clogging mud of the third aspect of the present invention, that the clogging sludges causes blockage in the cell ends of the honeycomb structural body, without a gap being created while there is less contraction due to crystallization during of the step of firing. Therefore, the step of burning with a minimal difference in terms of contraction between the honeycomb structural body and the clogging mud accomplished , whereby the occurrence of a gap or gap after the step of clogging is suppressed.

Consequently For example, the fourth aspect of the present invention is a method to produce an exhaust gas purification filter in which the Cell ends of a honeycomb structural body, which forms the exhaust gas purification filter, with a clogging sludges with a uniform Constipation depth can be blocked without any gap created between a clogged portion and a cell wall will, while an increased thermal shock resistance is effected.

BRIEF DESCRIPTION OF THE DRAWINGS

1 FIG. 12 is a perspective view of an exhaust gas purification filter of an embodiment according to the present invention, which is manufactured by a method according to one aspect of the present invention. FIG.

2 FIG. 15 is a longitudinal sectional view of the exhaust gas purification filter of the present embodiment shown in FIG 1 is shown.

3 FIG. 11 is a sectional view showing the flow of the exhaust gases through the exhaust gas purification filter of the present invention shown in FIG 2 is shown.

4 FIG. 15 is a perspective view of a honeycomb structural body constituting the exhaust gas purification filter of the present embodiment incorporated in FIG 1 is shown.

5 FIG. 12 is a longitudinal sectional view of the honeycomb structural body of the present embodiment shown in FIG 4 is shown.

6 10 shows a sectional view of the honeycomb structural body of the present embodiment having a structure in which masking materials are applied to both end surfaces.

7 10 shows a sectional view of the honeycomb structural body of the present embodiment having a structure in which the masking materials are perforated to form through-holes in the areas corresponding to the first cell ends that become clogged.

8th FIG. 12 is a schematic view of a step of dipping the honeycomb structural body of the present embodiment in a binder solution. FIG.

9 Fig. 12 is a fragmentary sectional view of the honeycomb structural body of the present embodiment, wherein an end face is dipped in the binder solution.

10 FIG. 12 is a schematic view of a step of dipping the honeycomb structural body of the present embodiment into a slurry-like clogging material. FIG.

11 FIG. 10 is a sectional view of the honeycomb structural body of the present embodiment in which the first cell ends are clogged with the slurry-like clogging material. FIG.

12 Fig. 12 is a photograph taken in place of a drawing taken while viewing an end surface of an exhaust gas purification filter (pattern E1) of the present embodiment opposite to an end surface using a loupe in a state in which a visible light beam is irradiated to the other end surface in one direction pointing towards an end face.

13 FIG. 10 is a photograph taken in the state of taking a visible light beam to the other end face in a state of being viewed from an end surface of another exhaust gas purification filter (pattern C) of the present embodiment opposite to an end surface using a magnifying glass Direction is blasted, which faces towards an end face.

14 FIG. 10 shows a photograph instead of a drawing taken at clogged portions from an end face of the exhaust gas purification filter (pattern E) of the present embodiment as a cut face using a microscope, the end face being cut at a plane substantially parallel to that of FIG End face of the exhaust gas purification filter is.

15 FIG. 10 is a photograph taken at clogged portions of an end surface of the exhaust gas purification filter (pattern C) of the present embodiment at a sectional area using the microscope, wherein an end surface has been cut at a plane substantially parallel to the plane. FIG End face of the exhaust gas purification filter is.

16 FIG. 10 is a photograph taken on clogged portions of an end surface of the exhaust gas purification filter (pattern E) of the present embodiment on the interface using a scanning electron microscope, the end surface being cut at a plane substantially parallel to the end surface. FIG of the exhaust gas purification filter.

17 FIG. 10 is a photograph taken on clogged portions of an end surface of the exhaust gas purification filter (pattern C) of the present embodiment on the interface using the scanning electron microscope, the end surface being cut at a plane substantially parallel to the end surface. FIG of the exhaust gas purification filter.

18 shows a sectional view of a honeycomb structural body of the prior art with a structure in which masking materials have been applied to both end surfaces.

19 Fig. 10 is a sectional view of the prior art honeycomb structural body having a structure in which the masking materials are perforated to form through-holes in the areas corresponding to the first cell ends being clogged.

20 FIG. 12 is a schematic view of a step of dipping the honeycomb structural body of the prior art into a slurry-like clogging material. FIG.

21 Figure 11 is a fragmentary sectional view of the prior art honeycomb structural body in which first cell ends are clogged with the slurry-like occlusive material.

22 shows a perspective view of the honeycomb structural body of the prior art.

23 shows a view in longitudinal section of the honeycomb structural body of the prior art, which in 22 is shown.

24 Fig. 10 is an enlarged view of a clogged portion formed at a cell end of the honeycomb structural body of the prior art.

25 FIG. 11 is an illustrative view of a clogging slurry for use in a method of manufacturing a honeycomb structural body of a second embodiment according to the present invention. FIG.

26 FIG. 3 is an illustrative illustration of a contact angle evaluation test for a clogging slurry used in the in-house 25 shown second embodiment has been executed.

27A and 27B show enlarged partial views of Spalt Auswertversuchen, which have been carried out in the second embodiment.

The 28A to 28C 10 are enlarged fragmentary views of clogging depth evaluation tests performed in the second embodiment.

29 FIG. 10 is a perspective view of the honeycomb structural body formed using the methods of FIG 25 clogging slurry has been produced.

DETAILED DESCRIPTION THE PREFERRED EMBODIMENTS

below are methods of manufacturing an exhaust gas purification filter Exhaust gas purification filter and a Verstopfungsschlämme based on various embodiments according to the present Invention in detail with reference to the accompanying drawings described. However, the present invention is not intended to be a be limited to such embodiment described below, and the technical concepts of the present invention can be found in Combination with other known technologies or other technologies, which have equivalent functions to those known technologies.

[First] Embodiment]

below is a method of manufacturing an exhaust gas purification filter for Capture of exhaust gases emitted from an internal combustion engine contained particles, thereby purifying the exhaust gases, under Reference to a first embodiment according to the present Invention described.

At the To run of the method of manufacturing an exhaust gas purification filter first a honeycomb preparation step carried out in which a ceramic Honeycomb structural body is prepared. The ceramic honeycomb structural body has an outer peripheral wall, partitions (Cell walls), within the outer peripheral wall be formed in a honeycomb structure, and a large number to cells passing through the partitions are divided so that they extend in an axial direction and have first and second cell ends open at both end surfaces are.

More accurate said ceramic honeycomb structural body either a compact, formed by extrusion molding, a prefired one Body, which results from a step for pre-firing the compact, or a burned body resulting from the step of firing the compact results.

The is called Extrusion molding a clay-containing ceramic material allows the Forming a compact with a honeycomb structure. The compact has an outer peripheral wall, porous partitions (Cell walls), the inside of the outer peripheral wall are formed in a honeycomb pattern, and a number of cells, through the partitions are divided and extend to both end surfaces in through holes. Of the Pressling is then dried.

For the ceramic Honeycomb structural body can either the dried compact, the burned body or the burned body be taken up.

If the compact or the preformed body is used as the ceramic honeycomb structural body, The step of burning can be carried out to the ceramic one Honeycomb structural body (in the forms of the compact or the pre-burned body) and the clogged sections made from the clogging material are to burn at the same time. This will allow the ceramic Honeycomb structural body has an advantage in that the cells and the associated clogged Sections joined together with a higher strength become.

Besides, if the burned body when the ceramic honeycomb structural body is used, only the clogged sections that cover the cell ends of the ceramic Honeycomb structural body clogged, burned. Through such a process has the ceramic honeycomb structural body (with a burnt body) a lower thermal expansion during the firing step. Therefore For example, the ceramic honeycomb structural body can be reduced in size thermal residual stress is fired at the area between the ceramic honeycomb structural body (burnt body) and the clogged sections.

Consequently the ceramic honeycomb structural body of one of the three types, which comprise the pressed body, the pre-burned body and the fired body, dependent on of the thermal expansion coefficient of the fired body and the particle diameter of the plugging material can be selected.

The ceramic honeycomb structural body (the fired body) may preferably have a main component made of cordierite. In this case, the exhaust gas purification filter can be manufactured by taking full advantage of the property of cordierite, resulting in reduced thermal expansion and increased thermal shock resistance. The ceramic honeycomb structural body made of cordierite as a main component can be manufactured by using a cordierite-dispensing raw material as a ceramic material which is formed into cordierite in the step of firing.

At the To run of the pretreatment step, both end faces of the ceramic honeycomb structural body are sealed in the binder solution, the water repellent Immersed agent or the hydrophobic treatment agent, wherein Thereafter, the ceramic honeycomb structural body is dried. The binder solution has a water-soluble Binders dissolved in water.

The binder solution may preferably be about 0.1 to 2.0 wt .-% of water-soluble Binder included.

If the water-soluble Binder less than 0.1 wt .-% makes up, then that remains water-soluble Binders attached to the partitions is attached, in an inappropriate quantity, from which the danger that gives a difficulty in obtaining a sufficient improved affinity between the clogged sections and the associated partitions becomes.

If Furthermore the water-soluble Binder more than 2 wt .-%, it is difficult to the water-soluble binder prepare. This means it becomes difficult, the water-soluble Binder completely in Dissolve water. If over it addition, the water-soluble Binder more than 2 wt .-%, it is difficult to the drying step at the pre-treatment step, which causes a hazard an extension the drying time. This leads to an increase of Production costs.

at the pretreatment step is further an end face of the ceramic honeycomb structural body in the binder solution immersed in a predetermined depth. At this moment results a capillary phenomenon in the binder solution in such a way that the water-soluble binder is in a larger area as the dipped area expands. That is, the water-soluble binder adheres on the cell walls the honeycomb structure in its more inward areas at.

at In the pre-treatment step, an end surface of the ceramic honeycomb structural body may preferably be in the binder solution in an immersion depth of about 1.5 mm to 2.0 mm from the end face of the ceramic honeycomb structural body be immersed.

If the immersion depth is less than 1.5 mm, the ceramic honeycomb structural body has an unsuitable one Adhesion range of the water-soluble Binder. Therefore, under the circumstances where the clogged Sections in the target cell walls in adequate are formed inwardly facing portions of the end face to the clog the first cell ends with a suitable strength or gull, a risk of occurrence of gaps (spaces) that partially formed in the inwardly facing portions of the cell walls become.

If about that In addition, the immersion depth is greater than 2.0 mm, must the immersion step for Pretreatment extended Run for a long time be what an increase the production costs.

The water-soluble Binder may preferably comprise water-soluble polymer, which consists of at least one element chosen from the group made of methylcellulose, hydroxylpropyl-methylcellulose, carboxy-methylcellulose, Hydroxy ethyl cellulose, starch, Polyvinyl alcohol, polyethylene oxide, sodium polyacrylate and polyacrylamide consists.

All these water-soluble Polymers can a suitable improved affinity between the clogging Material and the cell walls provide. Furthermore allows the application of a minor Amount of such a water-soluble Polymers showing a suitable improvement effect, what allows, the drying step in a shorter Time span during of the pretreatment step.

The water-repellent agent has the effect of causing an object repelled by the water repellent to have a water-repellent property. The hydrophobic treating agent has the effect of causing an object coated with the hydrophobic treating agent to cause a hydrophobizing property (hydrophobic) has.

Examples water repellent and hydrophobic treatment agent can Preferably, those agents include, for example, commercially be marketed. In particular, examples of such Water-repellent agent such as fluorine resin and its solution or the like. Furthermore can Examples of the hydrophobic treatment agent, for example, a solution of Hydrocarbon family or the like such as dimethyl silicone oil or the like include.

Of Furthermore, the pretreatment step may preferably be in one phase between the step of preparing the honeycomb and the masking step or between the masking step and the applying step of the clogging material.

The is called the ceramic honeycomb structural body is prepared in a step of preparing the honeycomb, wherein then the pretreatment step is performed and the masking step accomplished can be. About that Beyond is during the masking step, the masking material on an end face of the ceramic honeycomb structural body arranged to expose the first cell ends to be clogged, while second Cell ends that are not clogged are covered.

Furthermore In the masking step, the masking materials are applied to both end faces of the ceramic honeycomb structural body at the opening sections the cells are applied, after which the pretreatment step is carried out and then the step of applying the clogging material accomplished can be.

at the masking step is applied to the end surface of the ceramic honeycomb structural body Masking material perforated to form through holes in the areas which correspond to the first cell ends, the one with the clogging Material to be clogged while covered sections remain in the other areas left correspond to the second cell ends that are not clogged.

Especially become masking tapes at the two end surfaces of the ceramic honeycomb structural body applied and then for the purpose of removal using a laser beam or the like is melted or burned off to form the through holes in form the areas corresponding to the first cell ends, which are clogged with the clogging material. In such a way has each of the masking tapes exposed (open) sections in the areas that correspond to the first cell ends clogged and covered (closed) sections in the other areas corresponding to the second cell ends, which are not clogged, these being in a checkered pattern are formed. Examples of such a masking material may preferably be For example, a resin film (plastic film) or the like.

at the drying step following the pretreatment step about that In addition, the ceramic honeycomb structural body preferably by a Bubbles with hotter Air at temperatures of about 40 ° C to 120 ° C with a blowing speed of about 3 to 50 m / s dried become.

One allows such drying step a reduction in the drying time. The execution of the drying step in a natural Drying process causes the ceramic honeycomb structural body a longer Period of, for example, more than two hours is dried. Furthermore For example, the drying step may be performed by blowing the hot air not only to the outer peripheral wall of the ceramic honeycomb structural body but also to the inner areas of the respective cells.

If the temperature of the hot ones Air less than 40 ° C is, the drying step brings a less effective reduction the drying time with it. Furthermore results when the temperature of the hot air is more than 120 ° C, one thermal deterioration of the masking material, which is a danger of Contraction or melting, which then causes it if it is the pretreatment step subsequent to, for example, the To run the masking step is suspended. As a result, results a risk of deviation, which is in terms of positions the through holes resulting, for example, by the laser beam or be formed.

Further, if the blowing speed is less than 3 m / s, the drying step brings less reduction in the drying time. In addition, if the blowing speed is greater than 50 m / s, there is a danger that the masking materials will be peeled or broken.

at In addition, the step of applying the clogging material the two end surfaces the ceramic honeycomb structural body, resulting from the masking step and the subsequent pretreatment step arise, alternately in clogging material in the form of a sludges immersed, which acts as a material that blocks the clogged sections formed. This makes possible, that the clogging material is the first cell ends of the ceramic Honeycomb structural body on both end surfaces blocked by these.

Examples of the clogging material preferably a ceramic material such as cordierite or a cordierite-dispensing raw material. A dispersing of, for example, ceramic material and organic binder in water, the slime-like, Prepare clogging material.

at In addition, the step of firing is accompanied by the ceramic honeycomb structural body the first cell ends clogged with the clogging material are, burnt. At that moment, the clogging material is so burned that the clogged sections at the first cell ends of the ceramic honeycomb structural body be formed. In a case where the compact that is from the extrusion forming, or the preformed body as the ceramic honeycomb structural body in the step of preparing the honeycomb, the ceramic honeycomb structural body and the clogging material at the same firing step simultaneously get abandoned.

(Example 1)

below is a method of manufacturing an exhaust gas purification filter of the first embodiment according to the present Invention described in detail.

Of the Exhaust purification filter of the present embodiment may be used as a Device for capturing in from an internal combustion engine Exhaust gases contained particles are used, thereby reducing the exhaust gases to clean.

Like this in the 1 to 3 is shown has the exhaust gas purification filter 1 an outer peripheral wall 11 , porous partitions 2 which serve as cell walls and inside the outer peripheral wall 11 are formed in a honeycomb structure so as to extend in an axial direction, and a plurality of cells 3 passing through the dividing walls 2 shared. Both end faces of the cells 3 are with a variety of opening sections 31 at the second cell ends 3b are formed, and a plurality of clogged sections 32 at the first cell ends 3a are formed, formed.

In the present example, the exhaust gas purification filter has 1 an upstream side end surface 13 serving as an inlet for the exhaust gases and a downstream side end surface 14 acting as an outlet of the exhaust gases. In the cells 3 are the first cell ends 3a with the clogged sections 32 closed and are the second cell ends 3b with the opening sections 31 at the upstream side end surface 13 formed, wherein the opening portions 31 and the clogged sections 32 arranged in a checkerboard pattern. Similarly, in the cells 3 the first cell ends 3a closed with the clogged sections and the second cell ends 3b with the open portions at the downstream side end surface 14 educated.

In particular, they are in the cells 3 each the clogged sections 32 at the upstream side end surface 13 and the open portions at the downstream side end surface 14 , Thus, the cells have 3 alternately the open sections 31 and the clogged sections 32 at both the upstream side end surface 13 as well as the downstream side end surface 14 , In addition, the partitions (cell walls) 3 are formed with a large number of pores so that they are porous, to allow the passage of the exhaust gases through it, while the particles contained in them are captured.

Furthermore, the exhaust gas purification filter 1 a total size with a diameter of about 160 mm and an axial length of about 100 mm. Each of the cells 3 has a size with a cell thickness of about 3 mm and a cell spacing of about 1.47 mm.

In addition, the exhaust gas purification filter 1 made of cordierite, the cells 3 have square shapes in cross section. However, the cells can 3 be formed with other various cross-sectional shapes such as a triangular shape or a hexagonal shape or the like.

In addition, usually carry the partitions 3 a catalyst having at least one element selected from the group consisting of, for example, platinum, rhodium, palladium, barium and potassium, and the like.

Below is on the 4 to 11 to describe a method of manufacturing the exhaust gas purification filter of the present embodiment.

If the method of manufacturing the exhaust gas purification filter is carried out; at least one step for preparing a honeycomb, a masking step, a pretreatment step, a step of applying a clogging Materials and a step to burning performed.

The step of preparing a honeycomb becomes a ceramic honeycomb structural body 4 with one in the 4 and 5 prepared structure. That is, the ceramic honeycomb structural body 4 has an outer peripheral wall 41 , porous partitions (cell walls) 42 inside the outer perimeter wall 41 are formed in a honeycomb structural body, and a plurality of cells 3 on, passing through the dividing walls 42 are shared and linked to both end pages 43 and 44 extend.

In the masking step, as shown in FIG 6 Shown is masking materials 5 on the two end pages 43 and 44 each applied to both ends of the cells 3 to close. Subsequently, the masking materials 5 then subjected to a perforating step. In the perforating step, high-density energy is applied to the masking materials 5a using, for example, a laser beam (not shown) applied to through holes 321 in the fields of 325 form the first cell ends 3a while plugged with a clogging material while. covered sections in the other areas 315 leave the second cell ends 3b do not clog, as in 7 is shown.

Like this 7 is apparent, the ceramic honeycomb structural body 4 with the masking materials 5 covered so that each of the cells 3 at the cell end 3a on one end side 43 is open and covered with the area 315 at the second end of the cell 3b on the other end side 44 closed is. This will allow each cell 3 has one end closed with the clogging material with the other end left open, as described later.

In the pretreatment step, the two end faces become 43 and 44 of the ceramic honeycomb structural body 4 alternately in a binder solution 6 submerged containing the water-soluble binder mixed in water and placed in a vessel 60 is filled, like this in 8th is shown. Thereafter, the ceramic honeycomb structural body 4 dried.

In the step of applying the clogging material, the two end sides become 43 and 44 of the ceramic honeycomb structural body 4 which has been exposed to the masking step and the pretreatment step, into a slurry-like clogging material 320 immersed in a vessel 329 is filled, like this in 9 is shown. Then the first cell ends will be 3a of the ceramic honeycomb structural body 4 with the clogging material 320 clogged, like this in the 10 and 11 is shown.

In the firing step (firing step), the ceramic honeycomb structural body becomes 4 , whose first cell ends 3a with the clogging material 320 clogged, burned.

The Manufacturing method of the present embodiment is below detailed with reference to each of the different steps described.

[Step to prepare the honeycomb]

Talc, quartz glass and aluminum hydroxide were weighed and mixed as a raw material in a desired cordierite composition. To the weighed and blended raw material was added a pore-providing agent, a binder and water, etc., which were mixed and stirred to provide a clay-containing ceramic material. Then, the resulting clay-containing ceramic material was supplied to an extrusion molding machine for extrusion molding to thereby form a green honeycomb compact receive.

The green honeycomb pellet was then dried and then cut to a desired length. The compact had partitions (cell walls) formed in a honeycomb structure and a plurality of cell walls divided by the partition walls or partitions and extending to both end sides acting as an inlet and outlet, respectively (see Figs 4 and 5 ). Subsequently, at temperatures ranging from about 1350 to 1450 ° C, the green honeycomb was prebake for about 2 to 8 hours, resulting in a prebaked body 4 (a ceramic honeycomb structural body 4 ).

[Masking]

Subsequently, the masking materials 5 on the ceramic honeycomb structural body 4 on both end sides 43 and 44 each applied so that the same were covered, as in 6 is shown. Then, a high-density energy was applied to the masking materials 5 blasted using a laser beam to the through holes 321 in the fields of 325 form the first cell ends 3a which are clogged while the covered sections in the other areas 315 left the second cell ends 3b do not clog, as in 7 is shown. Thus, the honeycomb structural body was 4 in the uncovered areas 325 open, with the clogged sections 32 be clogged, and stayed in the covered areas 315 with the masking materials 5 locked. Further, in the present embodiment, resin films (plastic films) each having a thickness of 0.1 mm were used as the masking materials 5 applied.

[Pretreatment step]

Thereafter, a binder solution was prepared by dissolving methyl cellulose in hot water having a methyl cellulose concentration of about 0.35 wt%. Then the binder solution became 6 , which has been cooled to room temperature, in the vessel 60 poured, like this in 8th is shown. After that, it became an end page 43 of the honeycomb structural body 4 in the binder solution 6 in the vessel 60 was immersed for 20 to 30 seconds. The immersion depth of the honeycomb structural body 4 was chosen to be at a value of about 1.5 to 2.0 mm from the end side 43 was. During such a dipping step, as in 9 shown is the binder solution 6 partly in the end or end face 43 of the honeycomb structural body 4 over the through holes 321 , which caused the water-soluble binder to close to the partitions 42 the first cell ends 3a clung. A capillary phenomenon occurred on the binder solution 6 such that the binder solution 6 into the interior of the cell ends 3a over the through holes 321 penetrated. At that moment, had the binder solution 6 a surface level 62 that is higher than the surface level (level) 61 the binder solution 6 was like this in 9 is shown. This resulted because the binder solution 6 an excellent wetting property on the partitions 42 the cells 3 would have.

Subsequently, the other end side similarly became 44 of the honeycomb structural body 4 in the binder solution 6 immersed. Subsequently, the honeycomb structural body became 4 dried in a constant temperature bath at a temperature of about 95 ° C for two hours.

In such a way, the honeycomb structural body became 4 obtained with the water-soluble binder, that on the partitions 42 the first cell ends 3a attached to the sections 325 at the two end surfaces 43 and 44 of the ceramic honeycomb structural body corresponded.

[Step to apply the clogging material]

After that were weighed talc, quartz glass and aluminum hydroxide and as a Main raw material for a clogging material mixed with a clogged material Sections in a desired Composition was formed. A dispersant, binder and water, etc. were added and mixed with the main raw material, whereby a slurry-like, clogging material was prepared.

Like this in the 10 and 11 It was shown to be with the slime-like, clogging material 320 filled vessel 329 prepared. After that, the end page became 43 of the honeycomb structural body 4 which had been exposed to the masking step and pretreatment step, into the slurry-like clogging material 320 that in the vessel 329 filled, dipped. This has caused the clogging material 320 in the first cell ends 3a of the honeycomb structural body 4 about the Durchgangslö cher 321 with a suitable depth. In addition, the other end page became 44 of the honeycomb structural body 4 exposed to the same clogging step as it is at the end side 43 of the honeycomb structural body 4 was applied.

[Burning step]

Subsequently, the honeycomb structural body (the burned body) 4 and the clogging material 320 that in the first cell ends 3a was burned at a temperature of about 1400 ° C. This has caused the masking materials 5 burned away and from the honeycomb structural body 4 were removed. This resulted in an exhaust gas purification filter 1 that has the multiplicity of opening sections 31 and the multitude of clogged sections 32 at the two end surfaces 13 and 14 such that every cell 3 an end to that with the clogged section 32 was formed, and had another end, with the opening portion 31 was trained. This exhaust gas purification filter was treated as a sample E.

at The present example further has another exhaust gas purification filter as a pattern C made to a comparative example for comparison to get with the pattern E. This pattern C was the same Process as in the case of E manufactured with the exception that no pretreatment performed has been.

After that were in the present example experiments in the exhaust gas purification filters of the pattern E and the pattern C performed to the bond strengths between the clogged sections and the associated partitions. The connection states were checked by penetrating light was observed, a microscopic observation was executed from an inner area and an observation with a scanning electron microscope (SEM) in With regard to the cross section.

[Observation of penetrating light]

A visible light beam was irradiated on each exhaust gas purification filter of the patterns E and C in a direction from one end surface to the other end surface. In such a state, the other end face, which was opposite to the one end face of each pattern to which the visible light beam was irradiated, was observed with a magnifying glass (magnifying glass) to check the existence of leakage of light. The resulting photographs of the observation of the patterns E and C are in the 12 and 13 each shown. In addition, the show 12 and 13 in both cases the photographs under consideration with a magnification factor of 3.5.

[Microscopic examination from inside]

The exhaust gas purification filters for the patterns E and C were cut (split) at levels approximately at the middle portions of the sidewalls, which were substantially parallel to the end surfaces. Then, the clogged portions at the end surfaces were observed from the inside areas (from the sides of the separation area) using a microscope. The resulting photographs for the patterns E and C are in the 14 respectively. 15 shown. In addition, the show 14 and 15 in both cases the photographs under consideration with a magnification factor of 25.

[Examination with a scanning electron microscope from the inside]

An approximately central portion of each of the end faces of the exhaust gas purification filter for the patterns E and C was cut at a plane substantially perpendicular to the end side. Then, the clogged portions were observed on the cut surface using a scanning electron microscope. The resulting photographs for the patterns E and C are in the 16 respectively. 17 shown. In addition, the show 16 and 17 in both cases the photographs with a magnification factor of 20.

Like this 12 As a result, no leakage of light from the areas formed with the clogged portions on the end face or the end face of the pattern E exhaust gas purifying filter was observed. In contrast, as in 13 In the exhaust gas purification filter for the pattern C, it is shown that leakage of light occurred between the clogged portions and the partition walls in the areas formed with the clogged portions (see FIG kreister area in 13 ).

Furthermore, as was the case from the 14 and 16 8, in the pattern E, the clogged portions are substantially and completely connected to the relevant partition walls, and no gap penetrated in a direction from the inside to the end side in the relevant joined portion has been observed. In contrast, as was clear from the 15 and 17 4, a plurality of gaps or gaps (line gaps) are observed between the clogged portions and the relevant partitions in the pattern C (refer to circled portions in FIGS 15 and 17 ). A part of the gaps was found with a structure penetrating in a direction from the inside of the cell to the end side.

As listed above is, from the present example, that a temporary Immersion of the area to be clogged with the clogging material into the binder solution allows that an exhaust gas purification filter having a structure is obtained, with no gap or gap in the clogged sections occurs after the firing step, while being an excellent bonding property between the clogged section and the associated partition.

Of Further, although the present embodiment is by way of reference is described on the pretreatment step, between the Masking step and the step of clogging is performed, the present invention is not limited to such a sequence. The is called the pre-treatment step may even be carried out before the masking step, whereby the production of an exhaust gas purification filter is made possible, the excellent bond strength between a clogged Section and an associated Partition in similar Way as with the pattern E has. In addition, while the The present invention will be described with reference to an example is where the burned body as the ceramic honeycomb structural body is used, be understood that even the application of a compact, resulting from an extrusion molding results, and a fired body the production of an exhaust gas purifying filter that allows an excellent Connection property between a clogged section and an associated one Partition in similar Way as with the pattern E has.

In addition, while in the present example, the pretreatment step using the binder solution accomplished was the pre-treatment step using a water-repellent Be carried out by means of or a hydrophobic treatment agent instead of the binder solution. Even such an alternative allows the production of a Exhaust gas purification filter, which is an excellent bonding property between a clogged section and an associated partition in similar Way as with the pattern E has.

Second Embodiment

A Verstopfungsschlämme (a clogging mud) a second embodiment according to the present Invention for a use in a method of manufacturing an exhaust gas purification filter is described below.

The clogging material comprises at least aggregates, a dispersant and water. The aggregates contain ceramic powder which releases cordierite crystals during firing. Examples of such a ceramic powder include, for example, silica (SiO ₂ ), talc (Mg ₃ Si ₉ O ₁₀ (OH) ₂ ), aluminum hydroxide (Al (OH) ₃ ) and alumina (Al ₂ O ₃ ), and the like.

Of Further, examples of the dispersant include, for example Ammonium polycarbonate, polycarboxylic copolymer, ammonium polyacrylate and sodium polyacrylate and the like.

Furthermore the ceramic powder has an average particle diameter, from about 6 to 22 μm ranges (according to the standard: D50).

When the ceramic powder has an average particle diameter of less than 6 μm, a clogged portion that has clogged into a ceramic honeycomb structural body has an extremely increased contraction factor during the firing step. This causes a problem that a clearance or gap occurs between the clogged portion and an associated partition wall (cell wall). In contrast, when the ceramic powder has an average particle diameter of more than 22 μm, coarse particles of the ceramic are likely to be present Powder fail with ease. This results in occurrence of fine ceramic powder which clogs the cells of the ceramic honeycomb structural body, causing a problem that a gap occurs in a similar manner as mentioned above.

Of Furthermore, the clogging slurry has a contact angle in a size of less as about 114 °, the then results when the mud attached to the cell wall. Under such a condition Can the clogging mud even at four corners of a square-shaped cell without appearance a gap can be arranged.

If the contact angle exceeds the value of 114 °, results in a Problem in that there are gaps or gaps that follow result in the four corners of the cell.

The clogging mud may preferably have a contact angle in a value of more than Have 58 °, when it is attached to the cell wall.

Under In such a condition, the clogging slurry may enter the Cell ends with a uniform Blockage depth are plugged.

If The contact angle has a value of less than 58 °, there is a risk of Occurrence of an increase in the constipation depth to an excessive extent or a variation in the occlusion depth due to unevenness the shape of the cells.

Of Further, adjusting the viscosity of the clogging slurry and the surface property or the like of the cell wall, the contact angle between the clogging sludges and regulate the cell wall.

The viscosity the clogging mud can be adjusted by, for example, the salary rate (the Content fraction) of a dispersant is varied.

Furthermore can the surface property the cell wall can be adjusted by, for example, a water-soluble Film on the surface the cell wall in a manner described below is trained.

Furthermore the rate of incorporation of the dispersant may preferably be in one Value range of approximately 0.3 to 1.0 wt% S / S in terms of a proportion of a solid particle in relation to the aggregates.

If the incorporation rate of the dispersant is less than 0.3% by weight, takes the viscosity the clogging mud to, which leads to a danger, that when clogging with the clogging slurry at the cell ends of the Honeycomb structural body a difficulty occurs. If, in contrast, the salary rate of the dispersant greater than 1.0% by weight will not be additional Improvement of the effect observed, indicating the risk of deterioration the dispersibility of the clogging slurry causes.

Of Further, the clogging slurry may preferably be a binder with a salary rate in a value of less than approximately 0.5% by weight of S / S in terms of a proportion of solid in terms contained on the aggregates.

If the content of the binder exceeds 0.5% by weight S / S, takes the viscosity of the clogging mud to what a difficulty in clogging and a drop in the Strength of the clogging material causes.

Furthermore can Examples of the binder, for example, preferably methyl cellulose, Polyvinyl alcohol and agar or the like.

Of Further, a content rate of water may preferably be in a range of values of about 30 to 45% by weight, (added) based on a total weight of 100% by weight of the clogging slurry.

When the water content rate is less than 30% by weight, the viscosity of the clogging slurry increases, resulting in a danger of clogging difficulty. If, in contrast In addition, since the water content rate is larger than 45% by weight, there is a fear that a clogged portion having a convex-shaped central portion is formed, and in some cases, there is also a risk of pore formation.

[Third Embodiment]

One Method for producing an exhaust gas purification filter, which consists of a Honeycomb structural body a third embodiment according to the present Invention is described in detail below.

Of the Honeycomb structural body has an outer peripheral wall, porous Cell walls the inside of the outer peripheral wall are formed in a honeycomb pattern, and a large number at square-shaped cells divided by the cell walls are and to the two end sides of the ceramic honeycomb structural body in extend in its axial direction.

Of Further, the ceramic honeycomb structural body has first cell ends, which with a clogging mud be plugged, which consists of a cordierite mixed composition, and second cell ends that are not clogged.

The A method of manufacturing an exhaust gas purification filter of the present invention Embodiment has an extrusion molding step in which a compact honeycomb body with a base material in a honeycomb structure by extrusion molding is formed, wherein the compact honeycomb body is dried, the compact honeycombs in a given length is separated with a structure in which the cell walls in the Honeycomb patterns are formed and the large number of square shaped Cells through the cell walls are divided and extend to the two end pages.

Of Further, a pre-firing step is carried out to bring the compact honeycomb body to the Purpose of forming a honeycomb body pre-burn. Then it will be a masking step is carried out, wherein a masking material is applied to both end sides of the honeycomb body is going to get through holes in the areas corresponding to the first cell ends, and to form covered areas in the other areas which correspond to the second cell ends.

Furthermore a clogging step is carried out in which the clogging sludges on the first cell ends of the honeycomb body (via the through holes, the formed in the masking material) is applied.

Subsequently, will a first firing step is carried out, in which the honeycomb body and the clogging material stuffed into the first cell ends be fired at the same time.

at the manufacturing method of the third embodiment is the clogging sludges in a composition referring to the clogging sludges of the second listed above embodiment is described as using the clogging slurry stuffed into the honeycomb body becomes.

The Method for producing an exhaust gas purification filter, which consists of a Honeycomb structural body of the third embodiment according to the present Furthermore, the invention may preferably include a step in which a water-soluble Film on the surface the cell wall of the honeycomb structural body in an area that covered at least one blockage section, before the step to Applying the clogging material is temporarily formed.

This temporary Step allows an improvement of the surface property the cell wall, which allows, with ease, a contact angle between the clogging mud and define the cell wall in a range of less than about 114 °. Therefore, you can in a clogging step, the cell ends of the honeycomb structural body the clogging mud be clogged in a stable manner.

Examples of the water-soluble Films can preferably, for example, methyl cellulose, polyvinyl alcohol and Include agar or the like.

(Example 2)

Examples of the present embodiment are described below with reference to FIG 25 described.

In the present embodiment, as shown in FIG 25 shown is a clogging mud 320A at least aggregates 102 , a dispersant 104 , Water 106 and a bridging section 108 on.

The aggregates 102 contain ceramic powder which gives off cordierite crystals on firing and which has an average particle diameter of about 6 to 22 μm.

below this is described in detail.

In Example 2, plugging muds were prepared as samples E1 and E2 having the compositions shown in Table 1. In addition, plugging muds were prepared as samples C1 to C3 as comparative examples having the compositions shown in Table 1. In addition, a clogging slurry was prepared by using silica (SiO ₂ ) and alumina (Al ₂ O ₃ ) in the absence of a cordierite compound composition.

The clogging muds were prepared by placing the aggregates, water, dispersant and binder in a 5 liter vessel and mixing these components for about 12 to 48 hours at a stirring rate of about 60 revolutions per minute. [Table 1] template Aggregate (g) Dispersant wt% S / S Binder wt .-% S / S Water% by weight Rohmat. A Rohmat. B Rohmat. C Rohmat. D E1 385 762 524 263 0.5 0.1 35 E2 385 762 524 263 0.5 0.1 45 C1 385 762 524 263 0.5 0.1 30 C2 385 762 524 263 0.5 0.1 40 C3 385 762 524 263 0.5 0.1 40 C4 1408 - - 526 - 15 19

In Table 1, as the raw material A, silicon oxide (SiO ₂ ) was used. For the raw material B, talc (Mg ₃ Si ₄ O ₁₀ (OH) ₂ ) was used. For the raw material C, aluminum hydroxide (Al (OH) ₃ ) was used. For the raw material D, alumina (Al ₂ O ₃ ) was used.

Of Another was for the dispersant ammonium polycarbonate used and for the binder Methylcellulose was used.

Furthermore in Table 1, the content rates of the dispersant and of the binder in terms of the proportion of solids in terms listed on the aggregates. The Wassergehaltrate is in terms of Gehaltrate (added) on based on a total of 100 wt .-% of clogging sludge shown.

After that the resulting clogging slurry was used, and the contact angle and the average particle diameter of the ceramic powder were measured.

<Contact angle measurement test>

Like this in 26 was shown, the resulting slurry 320A on a base material 110 dropped from a main component to cordierite, dropped, and the contact angle θ between the slurry 320A and the surface of the base material 110 was measured. In this regard, the basic material was 110 formed in a plate corresponding to a cell wall of a honeycomb structural body, the in the same structure as Example 3 described below. The base material 110 had a surface on which no water-soluble film was formed. Evaluations were graded "P" (positive), "G" (good) and "N" (negative), with the results "P" and "G" accepted and the result "N" discarded.

(Evaluation Standards)

"P": The contact angle θ is in a size range of about 58 to 114 °.

"G": The contact angle θ is included a size of less as about 58 °.

"N": The contact angle θ is included a size of more as about 114 °.

<Particle diameter measuring test>

Of the Particle diameter of the ceramic powder was measured using a grain size distribution measuring device measured by the "Nikkiso" Co., Ltd. (under the brand "Microtrac") and sold becomes. In the evaluations one result "G" was accepted and another result "N" was rejected.

(Evaluation Standards)

"G1": the particle diameter is in a size range of about 6 to 22 μm.

"N1": the particle diameter is less than 6 μm in size or greater than about 22 μm in size. [Table 2] template Contact angle (°) Particle diameter (μm) Thermal shock behavior E1 P G G E2 G G G C1 N G G C2 N N G C3 G N G C4 G G N

As as shown in Table 2, samples E1 and E2 showed of the present embodiment according to the present Invention favorable Results in terms of both sizes including the contact angle and the particle diameter.

Of Further, the pattern C1, which as a comparative example of FIG Present invention served, a result in which the contact angle exceeded the upper limit of the present invention.

Of Further, the pattern C2 showed as another comparative example The present invention served another result, in which the particle diameter took a size, lower than a lower limit of the present invention was.

Furthermore showed the pattern C3, which as another comparative example of served the present invention, another result in which the Particle diameter took a size, exceeding an upper limit of the present invention.

also was the pattern C4, which as another comparative example of the present Invention, not in a cordierite blend composition educated.

The method of manufacturing an exhaust gas purification filter of the third embodiment according to The present invention will be described below in detail.

The A method of manufacturing an exhaust gas purification filter therefrom embodiment generally comprises an extrusion molding step, a step to the temporary Burning, a masking step, a step for applying a clogging material and a firing step (firing step).

In the manufacturing method of the present embodiment, which is described in 29 is shown, extrusion molding is performed using a cordierite mixed raw material to form a compact in a honeycomb structural body 201 train. The honeycomb structural body 201 has an outer peripheral wall 211 , a variety of porous cell walls 202 in the form of partitions inside the outer peripheral wall 201 are formed in a honeycomb structure, and a large number of square-shaped cells 203 on through the cell walls 202 inside the outer peripheral wall 211 are divided so that they extend in an axial direction. The resulting compact, made from cordierite mixed raw material, then becomes a plugging slurry 320A so dipped that the ends of the cells 203 (hereinafter these are referred to as "first cell ends 203a " designated) with a clogging material 100 be clogged.

below the manufacturing method of the present embodiment is detailed described.

The honeycomb structural body 201 is made of a main component of cordierite having a theoretical composition represented by 2 MgO · 2Al ₂ O ₃ · 5SiO ₂ . Typically, cordierite contains from about 49.0 to 53.0 weight percent SiO ₂ , from about 33.0 to 37.0 weight percent Al ₂ O _3, and from about 11.5 to 15.5 weight percent. -% of MgO.

Examples of raw material for the honeycomb structural body 201 comprise a mixture of cordierite mixed raw material formed in a desired cordierite composition to which an auxiliary molding agent is added with a mixture which is kneaded. Examples of the mixed cordierite raw material include silica (SiO ₂ ), talc (Mg ₃ Si ₄ O ₁₀ (OH) ₂ ), aluminum hydroxide (Al (OH) ₃ ) and alumina (Al ₂ O ₃ ), and the like. In addition, oxides, hydroxides and chlorides or the like constituting a Mg source, Al source and Si source can be used. These include, for example, kaolin (Al ₂ Si ₂ O ₅ (OH) ₄ ), serpentine (Mg ₃ Si ₂ O ₅ (OH) ₄ ), pyrophyllite (Al ₂ Si ₄ O ₁₀ (OH) ₂ ) and brucite (Mg (OH ) ₂ ).

Of Further can Examples of the auxiliary molding agent used in the cordierite mixed raw material added is usually available standing lubricant and humectant and binder or the like exhibit. Examples of a lubricant and a humectant For example, wax include water-soluble polyalcohol derivatives and surface agents (Surfactant Fabric) or the like. About that In addition, examples of binders include, for example, methyl cellulose, Polyvinyl alcohol, agar or the like.

At first were the cordierite mixed raw material and the auxiliary molding agent with each other mixed and then kneaded to form a raw material.

In the extrusion molding, the raw material was extrusion-molded to provide a compact in a honeycomb structural body. This compact was dried and then separated in a predetermined length. This compact formed the honeycomb structural body 201 who in 29 is shown, and the cell walls 202 and a variety of square shaped cells 203 that passes through the cell walls 202 divided and extending to the two end sides of the compact. Extrusion molding under extrusion pressure of a size ranging from about 100 to 200 kg / cm ² was extrusion speeds of about 1.0 to 2.0 m / min. and raw material temperatures ranging in size from about 10 to 20 ° C.

After that in one step of pre-firing, the honeycomb pellet was prefired, causing a honeycomb body was trained. This step of pre-firing was at a Temperature of about 1400 ° C one hour long running. By such a step, the contraction of the honeycomb body was almost completed.

Subsequently, in the masking step, masking tapes were attached to both end sides at the end sides thereof between the opening portions of the honeycomb body and perforated in the areas facing the first cell ends 203a that were clogged, and covered in the other areas that the second cell ends 203b that were not blocked.

Thereafter, in the step of applying the clogging material, the honeycomb body became a clogging slurry 320A dipped to allow the first cell ends 203a with the clogging mud 320A be clogged.

In the step of applying the clogging material, plugging muds (samples E1 and E2 and samples C1 to C4) prepared in example 2 were taken to be the clogging slurry 320A applied.

Then In the firing step, the honeycomb bodies and the clogging slurry were used was stuffed into the first cell ends, at the same time at one Temperature of about 1430 ° C for about 30 hours burned.

Thus, a honeycomb structural body became 201 obtained in which the first cell ends were provided with the clogged sections.

Thereafter, evaluation experiments were conducted using the resulting honeycomb body 201 carried out.

<Space experiment>

One Gap or gap between the clogged portion and the associated Cell wall was checked by a light penetration test, wherein this evaluation was done was confirmed by the presence of a gap.

27A shows the result in the pattern E1 and 27B shows the result in the pattern C1.

Of Further, the patterns E2, C3 and C4 were compared with the Each structure found that the clogging sludge in the Cell ends even up to the four corners of each cell with no gap was stuffed with the same result as the pattern E1.

Moreover, in the pattern C2, it was found that the first cell ends 203a as gaps (column) 264 at the squares as in the pattern C1.

<Constipation depth attempt>

The Blockage depth was measured by taking an image of a blockage shape taken in cross-section using an X-ray CT was (X-ray computed tomography).

28A shows the results in patterns C1 and C2; 28B shows the result in the pattern E1; and 28C shows the results for the samples E2, C3 and C4.

<Thermal shock behavior>

With regard to the thermal shock properties (thermal shock resistance), the honeycomb bodies became 201 placed in an electric oven at a temperature of about 650 ° C for about 20 minutes, after which the honeycomb bodies 201 were removed from the oven and left in an environment at room temperature. Thereafter, evaluations were made as to whether cracks are in the honeycomb bodies 201 found or not. In the evaluation results shown in Table 2, acceptable results are shown with a symbol "G", and results to be discarded with "N" are shown.

(Evaluation Standards)

"G": No crack was in the honeycomb body 201 found.

"N": A crack was applied to the honeycomb body 201 found.

Like this from the 27A and 27B and from the 28A to 28C As is apparent, the pattern E1 representing the present embodiment showed favorable evaluation results in each Point with regard to the gap and the blockage depth.

Further, in the pattern E <b> 2 representing the present embodiment, the honeycomb body was 201 successful in that it had a structure in which the first cell ends could each be clogged at a predetermined clogging depth without occurrence of a gap. However, the E2 pattern showed greater variations in clogging depth than the clogging depth of the E1 pattern. Therefore, it is understood that the contact angle between the plugging slurry and the cell wall may preferably further be within a range of about 58 to 114 degrees.

Of Further, the pattern C1, which as a comparative example of FIG The present invention serves a contact angle which is an upper Limit value of the contact angle specified by the present invention will, passed, and the clogging mud barely clogged the given cell ends to a predetermined Depth without gaps or gaps.

Furthermore showed the pattern C2, which as another comparative example of present invention serves a contact angle of less than the upper limit of the contact angle, in the present Invention is specified. Therefore, during the burning step, the clogging mud clogging to crystallization with a resulting Increase in the contraction, which causes column or interspaces between the clogging mud and the cell wall after the plugging step.

Furthermore showed the pattern C3, which as another comparative example of The present invention serves an average particle size, the exceeded an upper limit of average particle size, specified by the present invention. This leads to a Increase in the precipitation or precipitation rate of the aggregates in the mud, which leads to a water rich condition. Such a rich in water sludges got into the cell ends, the middle of each clogged Section was formed in a concave shape. It was also causes a pored section to inherently be in the central area of the clogged portion depending from the circumstances revealed.

Of Further, the pattern C4 included as another comparative example The present invention serves the aggregates in the absence the mixed ceramic composition for forming cordierite in the Burning, resulting in a final product with thermal shock properties led, that was discarded.

As listed above is possible the fact that the average particle diameter of the ceramic powder so chosen he was in a size range of about 6 to 22 μm (according to the standard: D50) lies that contraction due to crystallization while the step of burning the clogging slurry is suppressed. This leads to a Reduction of contraction of the obstruction section during the Firing step, which prevents a gap on one Corner of each cell is formed after the Verstopfungsschritt.

Therefore it gets at the blockage mud and the method for producing a honeycomb structural body possible ceramic honeycomb structural body to receive, which has a clogged section and in which no interspaces or gaps between the clogged portion and the associated cell wall occur while this excellent thermal shock properties shows.

While the specific embodiments of the present invention are described in detail for professionals be obvious that various essays and alternatives to the details given in the light of the overall doctrine of the Revelation accomplished can be. Accordingly, the disclosed special designs merely serve as an illustration and not the scope of restrict the present invention, in the attached claims is defined.

The exhaust gas purification filter, an associated manufacturing method, and a clogging slurry for use in the manufacturing method are disclosed. A ceramic honeycomb structural body is prepared with a structure having a plurality of cells separated by cell walls and with masking materials applied to both end faces. A pretreatment step is carried out to dip both end sides in a binder solution containing water-soluble binder dissolved in water, a water-repellent agent or a hydrophobic treatment agent, and to dry the honeycomb structural body to form water-soluble films at the cell ends of the honeycomb structural body , Subsequently, the cell ends are clogged with a clogging slurry to clogging sections and then the honeycomb structural body and the plugging portions are fired. In a preferred embodiment, the clogging slurry comprises aggregates, a dispersant and water. The aggregates comprise a ceramic powder which releases cordierite crystals upon firing.

Claims (18)

A method of manufacturing an exhaust gas purifying filter for trapping particulates contained in an exhaust gas discharged from an internal combustion engine to thereby purify the exhaust gas, comprising the steps of: a honeycomb body manufacturing step of making a ceramic honeycomb structural body ( 1 . 4 . 201 ), which has an outer peripheral wall ( 11 . 211 ), Partitions ( 2 . 42 . 202 ) which are formed inside the outer peripheral wall in a honeycomb pattern and serve as cell walls, and a plurality of cells (FIG. 3 . 203 ), which are separated by the partitions and extending to both end sides ( 13 . 14 ) of the honeycomb structural body, wherein it has first cell ends ( 3a . 203a ), which become clogged, and second cell ends ( 3b . 203b ), which are not clogged; a masking step for applying a masking material ( 5 ) on the two end pages ( 13 . 14 ) of the honeycomb structural body ( 1 . 4 . 201 ) to form through holes in areas adjacent to the first cell ends ( 3a . 203a ), which are associated with clogging sections ( 32 . 232 ) are occluded while covering the other remaining areas facing the second cell end ( 3b . 203b ) that are not clogged; a pretreatment step that includes a step of immersing the two end faces ( 13 . 14 ) of the honeycomb structural body in a binder solution ( 6 ) in which water-soluble binder is dissolved in water, in a water-repellent or in a hydrophobic treatment agent, and for drying the honeycomb structural body; a plugging material application step for dipping the two end faces ( 13 . 14 ) of the honeycomb structural body which has been subjected to the masking step and the pretreatment step, into a slurry-like plugging material ( 320 . 320A ) acting as a material of the plugging sections, such that the first cell ends ( 3a . 302a ) with the blockage sections ( 32 . 232 ) are clogged; and a firing step for firing the honeycomb structural body ( 1 . 4 . 201 ) together with the blockage sections ( 32 . 232 ) located in the first cell ends ( 3a . 203a ) are located. Method for producing an exhaust gas purification filter according to claim 1, characterized in that the binder solution about 0.1 to 2.0 wt .-% of the water-soluble Binder contains. Method for producing an exhaust gas purification filter according to claim 1 or 2, characterized in that the water-soluble binder water-soluble Contains polymer, which is composed of at least one element that is derived from the Group selected consisting of methylcellulose, hydroxylpropyl-methylcellulose, carboxy-methylcellulose, Hydroxy ethyl cellulose, starch, Polyvinyl alcohol, polyethylene oxide, sodium polyacrylate and polyacrylamide consists. Method for producing an exhaust gas purification filter according to one the claims 1 to 3, characterized in that the pretreatment step between the honeycomb manufacturing step and the masking step or between the masking step and the Constipation material application step is performed. Method for producing an exhaust gas purification filter according to one of claims 1 to 4, characterized in that the ceramic honeycomb structural body ( 1 . 4 . 201 ) At least one composed of a clay-containing ceramic material formed by extrusion molding and having an outer peripheral wall, partitions formed in the interior of the outer peripheral wall in a honeycomb pattern, and a plurality of cells, which are divided by the partition walls and to extending therethrough, after which the compact is dried, a prebaked body resulting from the compact which is prebaked, and / or having a fired body resulting from firing of the compact or prefired body. Method for producing an exhaust gas purification filter according to one of claims 1 to 5, characterized in that during the pretreatment step the ceramic honeycomb structural body ( 1 . 4 . 201 ) is dried by blowing hot air at temperatures of about 40 ° C to 120 ° C at an air velocity of about 3 to 50 m / s. Method of manufacturing an exhaust gas purification filter according to claim 3, characterized in that in that, during the pretreatment step, the step of drying the honeycomb structural body is carried out at a temperature of about 95 ° C for two hours. Exhaust gas purification filter produced by the method for Producing an exhaust gas purification filter according to one of claims 1 to 7 is made. Blockage sludge ( 320A ) for use in a method of manufacturing an exhaust gas purification filter made of a honeycomb structural body ( 201 ), which has an outer peripheral wall ( 211 ), Cell walls ( 202 ) formed inside the outer peripheral wall in a honeycomb pattern and a large number of square-shaped cells (FIG. 203 ), which are separated by the cell walls and extend to both end sides of the ceramic honeycomb body, having first cell ends (FIGS. 203a ), which become clogged, and second cell ends ( 203b ), which are not clogged, the clogging slurry comprising: at least aggregates ( 102 ), a dispersing agent ( 104 ) and water ( 106 ); where the aggregates ( 102 ) contain ceramic powder which gives cordierite crystals on firing and which has an average particle diameter ranging from 6 to 22 μm (according to the standard: D50); and wherein the plugging slurry adheres to the cell walls each at a contact angle of less than about 114 °. Verstopfungsschlämme according to claim 9, characterized in that the contact angle is a size of more as about 58 ° has. Verstopfungsschlämme according to claim 9 or 10, characterized in that the dispersant a Salary share with one size, the expressed as a proportion of a solid part with respect to the aggregates of about 0.3 to 1.0% by weight S / S is sufficient. Blockage slurry according to one of claims 9 to 11, characterized in that the slurry-like clogging material ( 320 . 320A ) further comprises a binder having a content content in a size expressed as a proportion of a solid portion relative to the aggregates of less than about 0.5% by weight S / S. Verstopfungsschlämme according to one the claims 9 to 12, further characterized by: Water with one Salary component in a size that based on a total weight of 100% by weight of the clogging slurry of approximately 30 to 45% by weight (added) enough. Clogging slurry according to any one of claims 9 to 13, characterized in that the aggregates comprise at least one element selected from the group consisting of silicon oxide (SiO ₂ ), talc (Mg ₃ Si ₄ O ₁₀ (OH) ₂ ), aluminum hydroxide (Al (OH) ₃ ) and alumina (Al ₂ O ₃ ). Verstopfungsschlämme according to one the claims 9 to 14, characterized in that the dispersant at least comprises an element selected from the group consisting of ammonium polycarbonate, Polycarboxylcopolymer, ammonium polyacrylate, sodium polyacrylate exists. Verstopfungsschlämme according to one the claims 9 to 15, characterized in that the dispersant a Salary component in one size, the expressed as a proportion of a solid part with respect to the aggregates of about 0.3 to 1.0% by weight S / S is sufficient. Method for producing an exhaust gas purification filter, which consists of a honeycomb structural body ( 201 ), which has an outer peripheral wall ( 211 ), porous cell walls ( 202 ) formed inside the outer peripheral wall in a honeycomb pattern and a large number of square-shaped cells (FIG. 203 ) which are separated by the cell walls and which extend to both end sides of the ceramic honeycomb structural body in its axial direction, the first cell end ( 203a clogged with a plugging slurry composed of a cordierite mixed composition and second cell ends ( 203b ), which are not clogged, characterized by the following steps: Extrusion molds for molding a honeycomb compact ( 201 ) with a base material in a honeycomb structure by extrusion molding, drying the compact honeycomb body, cutting the compact honeycomb body in a predetermined length with a structure in which the cell walls are formed in the honeycomb pattern and the large number of square shaped cells (FIG. 203 ) are separated by the cell walls and extend to both end surfaces; Pre-firing the compact honeycomb body around a honeycomb body ( 201 ) to train; Masking for applying a masking material on both end sides of the honeycomb body ( 201 ) to form through holes in the areas corresponding to the first cell ends and to form covered areas in the other areas corresponding to the second cell ends; Clogging for applying the clogging mud ( 320A ) at the first cell ends of the honeycomb body ( 201 ) via the through-holes formed in the masking material; simultaneous burning of the honeycomb body ( 201 ) and the plugging material ( 320A ), with which the first cell ends have been blocked; and further that the plugging slurry ( 320A ) according to claim 9 to 13 is used as the clogging slurry with which the honeycomb body ( 201 ) is clogged. A method of manufacturing an exhaust gas purification filter according to claim 17, characterized in that, prior to the execution of the plugging step, at least the surfaces of the first cell ends of the honeycomb body ( 201 ) are temporarily formed with water-soluble films.