Coating attachment

Abstract

To provide a coating attachment for suppressing adhesion of a coating liquid to a part of an outer skin of a honeycomb substrate when the coating liquid is applied to the inner wall of a flow path of the honeycomb substrate by a suction method. [Solution] A coating attachment for applying a coating liquid to the inner walls of a flow path of a honeycomb substrate by a suction method, the coating attachment having a generally cylindrical shape with a first opening end at one end and a second opening end at the other end, a coating liquid storage section at the first opening end, and a substrate abutment section for abutting the outer peripheral edge of the end of the honeycomb substrate on the second opening end side of the coating liquid storage section, the substrate abutment section having a tapered surface whose inner diameter increases toward the second opening end side.

Description

[Technical field]

[0001] The present invention relates to a coating attachment used for applying a coating liquid to the inner walls of flow channels of a honeycomb substrate by a suction method. [Background technology]

[0002] An exhaust gas purification catalyst device for purifying exhaust gas emitted from an internal combustion engine of an automobile or the like has a configuration in which, for example, a catalyst coating layer containing an exhaust gas purification catalyst is applied to the inner walls of the flow paths of a honeycomb substrate.

[0003] As a manufacturing method of such an exhaust gas purification catalyst device, for example, a method including a coating step by the "suction method" is known (Patent Documents 1 to 3). The "suction method" is a method in which a coating liquid for forming a catalyst coat layer is placed on one end face of a honeycomb substrate and sucked from the opposite end face to extend the placed coating liquid into the flow path of the honeycomb substrate. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2007-268484 A [Patent Document 2] JP 2015-039672 A [Patent Document 3] JP 2006-015205 A Summary of the Invention [Problem to be solved by the invention]

[0005] When a coating liquid is applied to the flow passages of a honeycomb substrate by a suction method, the coating liquid may adhere to a part of the outer skin of the honeycomb substrate. The catalytic components such as catalytic precious metals contained in the coating liquid adhered to the outer skin of the honeycomb substrate do not contribute to purifying exhaust gas. Therefore, when the coating liquid is applied, adhesion of the coating liquid to a part of the outer skin of the honeycomb substrate leads to a loss of catalytic components.

[0006] The present invention has been made in view of the above circumstances. An object of the present invention is to provide a coating attachment for suppressing adhesion of a coating liquid to a part of an outer skin of a honeycomb substrate when the coating liquid is applied to an inner wall of a flow path of the honeycomb substrate by a suction method. [Means for solving the problem]

[0007] The present invention is as follows.

[0008] A coating attachment for applying a coating liquid to an inner wall of a flow channel of a honeycomb substrate by a suction method, comprising: The container has a generally cylindrical shape with a first open end at one end and a second open end at the other end, a coating liquid storage portion at the first open end, and a substrate abutment portion for abutting against an outer peripheral edge of an end portion of the honeycomb substrate, the substrate abutment portion being located closer to the second open end than the coating liquid storage portion; The substrate contact portion has a tapered surface whose inner diameter increases toward the second opening end. Coating attachment. Aspect 2: On the second opening end side of the substrate contact portion, A connecting portion that coaxially surrounds the honeycomb substrate; and A substrate fixing portion for fixing the honeycomb substrate by coaxially surrounding the honeycomb substrate. In this order, The connecting portion has an opening for connecting a region of the outer peripheral surface of the honeycomb substrate near the substrate abutment portion to outside air. 2. The coating attachment according to claim 1. Aspect 3 is the coating attachment according to Aspect 2, wherein the opening of the connecting portion extends in a circumferential direction of the connecting portion. Aspect 4 is the coating attachment of Aspect 3, wherein the opening of the connecting portion extends around the entire circumference of the connecting portion. Aspect 5: The coating attachment according to Aspect 4, wherein, among the connecting portions, the portion on the first opening end side of the opening and the portion on the second opening end side of the opening are connected inside the opening by a plurality of columnar portions spaced apart from each other in the circumferential direction of the connecting portion. Aspect 6: The coating attachment according to Aspect 5, wherein a cross-sectional shape obtained by cutting the columnar portion in a direction perpendicular to the axial direction of the coating attachment is circular, elliptical, polygonal, or arc-shaped. Aspect 7: The coating attachment according to any one of Aspects 1 to 6, wherein the base material contact portion is made of an elastic material. Aspect 8: The coating attachment according to any one of Aspects 1 to 6, wherein an angle formed between the tapered surface of the base material contact portion and the axis of the coating attachment is 35° or more and 70° or less. Aspect 9: The coating attachment according to any one of Aspects 1 to 6, wherein the coating liquid storage portion has a shape in which the inner diameter expands as it goes toward the first opening end side. Aspect 10: The coating attachment according to any one of Aspects 2 to 6, wherein the base material fixing portion has a balloon-shaped member for pressing and fixing the outer peripheral surface of the honeycomb base material.

Advantages of the Invention

[0009] According to the coating attachment of the present invention, when coating a coating liquid on the inner wall of the flow path of the honeycomb base material by the suction method, adhesion of the coating liquid to a part of the outer skin of the honeycomb base material is suppressed.

Brief Description of the Drawings

[0010] [Figure 1] FIG. 1 is a schematic cross-sectional view showing an example of the configuration of the coating attachment of the present invention. [Diagram 2] FIG. 2 is a schematic cross-sectional view showing a state in which the coating attachment of FIG. 1 is mounted on a honeycomb base material. [Diagram 3] FIG. 3 is a schematic cross-sectional view showing another example of the configuration of the coating attachment of the present invention. [Figure 4] FIG. 4 is a schematic cross-sectional view showing a state in which the coating attachment of FIG. 3 is mounted on a honeycomb substrate. [Diagram 5] FIG. 5 is a perspective view of the coating attachment of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] <Coating attachment> The coating attachment of the present invention comprises: A coating attachment for applying a coating liquid to an inner wall of a flow path of a honeycomb substrate by a suction method, The container has a generally cylindrical shape with a first open end at one end and a second open end at the other end, a coating liquid storage portion at the first open end, and a substrate abutment portion for abutting against an outer peripheral edge of an end portion of a honeycomb substrate, the substrate abutment portion being located closer to the second open end than the coating liquid storage portion; The substrate contact portion has a tapered surface whose inner diameter increases toward the second opening end. This is a coating attachment.

[0012] The coating attachment of the present invention further comprises: On the second opening end side from the substrate abutment portion, A connecting portion that coaxially surrounds the honeycomb substrate; and A substrate fixing portion for fixing the honeycomb substrate by coaxially surrounding the honeycomb substrate. in that order.

[0013] In this case, the connecting portion may have an opening for connecting the region of the outer circumferential surface of the honeycomb substrate near the substrate abutment portion to the outside air.

[0014] The coating attachment of the present invention has a substrate abutment portion for abutting the outer peripheral edge of the end portion of the honeycomb substrate, which has a tapered surface, thereby preventing the coating liquid from adhering to part of the outer skin of the honeycomb substrate.

[0015] In the conventional technology, when a coating liquid is applied to the inner walls of the flow channels of a honeycomb substrate by a suction method, the coating liquid adheres to part of the outer skin of the honeycomb substrate mainly for the following two reasons.

[0016] First, when the coating attachment is placed on the upper end face of the honeycomb substrate, the adhesion between the substrate abutment portion and the honeycomb substrate is poor, which may cause the coating liquid to leak from the abutment portion during suction.

[0017] Secondly, when a single coating attachment is used to continuously apply coating liquid to multiple honeycomb substrates, it is possible that the coating liquid remaining on the substrate contact portion may adhere to part of the outer skin of the next honeycomb substrate.

[0018] In this regard, since the coating attachment of the present invention has a tapered surface at the substrate contact portion, when the attachment is placed on the upper end face of the honeycomb substrate, the substrate contact portion and the honeycomb substrate are in good contact with each other, and leakage of the coating liquid from the contact portion is suppressed. Furthermore, since the coating attachment of the present invention has a tapered surface at the substrate contact portion and has a small contact area with the honeycomb substrate, it is believed that even if there is any coating liquid remaining on the substrate contact portion, it is unlikely to adhere to part of the outer skin of the honeycomb substrate.

[0019] Furthermore, when the coating attachment of the present invention has a connecting portion and a substrate fixing portion on the second opening end side (lower side) than the substrate abutment portion, and the connecting portion has an opening for connecting the area of ​​the outer surface of the honeycomb substrate near the substrate abutment portion to the outside air, even if there is a small gap at the contact portion between the substrate abutment portion and the honeycomb substrate during suction, an airflow will be generated in the direction of the coating liquid storage portion, which is thought to highly suppress leakage of the coating liquid from the abutment portion.

[0020] It is believed that the combination of the above-mentioned features of the coating attachment of the present invention highly suppresses adhesion of the coating liquid to a portion of the outer skin of the honeycomb substrate during coating. However, the present invention is not limited to a specific theory.

[0021] The components of the coating attachment of the present invention will now be described in order.

[0022] <Outline> The coating attachment of the present invention has a generally cylindrical shape with a first opening end open at one end and a second opening end open at the other end.

[0023] The coating attachment of the present invention is used to apply a coating liquid to the inner walls of the flow paths of a honeycomb substrate by a suction method. During coating, the honeycomb substrate is placed or fixed so that its axial direction is approximately parallel to the vertical direction. The coating attachment of the present invention is used by placing it on the upper end face of the honeycomb substrate in this state, with the first open end facing upward and the second open end facing downward. More specifically, it is envisaged that the coating attachment of the present invention will be used by placing it so that the tapered surface of the substrate abutment portion thereof abuts against the outer peripheral end of the upper end face of the honeycomb substrate.

[0024] Therefore, the coating attachment of the present invention has a generally cylindrical shape which is advantageous for use by placing it on the end face of a honeycomb substrate.

[0025] Hereinafter, in this specification, the direction toward the first opening end of the coating attachment may be referred to as the "upper direction" or "upper side," and the direction toward the second opening end may be referred to as the "lower direction" or "lower side."

[0026] <Coating liquid storage section> The coating liquid reservoir in the coating attachment of the present invention is a portion for storing the coating liquid prior to suction when the coating liquid is applied to the inner walls of the flow paths of the honeycomb substrate by a suction method.

[0027] When the coating attachment of the present invention is placed on the end face of the honeycomb substrate, it becomes possible to store the coating liquid in the space defined by the end face of the honeycomb substrate, the inner wall of the portion extending from the substrate abutment portion to the first open end, and the surface to which the first open end belongs. Therefore, the coating liquid storage portion may have any shape.

[0028] The coating liquid storage section may have a shape in which the inner diameter increases toward the first open end (upper side), for example. Such a shape has the advantage that it can store a large amount of coating liquid and can be easily cleaned after use.

[0029] The capacity of the coating liquid storage section may be appropriately set depending on the planned coating amount.

[0030] The coating liquid storage portion may be made of a material appropriately selected by a person skilled in the art. The coating liquid storage portion may be made of, for example, a synthetic resin, a metal, a ceramic, etc. The coating liquid storage portion may be made entirely of the same material, or may be made by combining a plurality of portions made of different materials.

[0031] <Base material contact part> The coating attachment of the present invention has a substrate abutting portion for abutting against the outer periphery of the end portion of the honeycomb substrate, on the second open end side (lower side) than the coating liquid reservoir.

[0032] The inside of this substrate contact part is a tapered surface whose inner diameter increases toward the second open end (lower side). Therefore, the uppermost part of the substrate contact part (the part of the substrate contact part closest to the first open end) is the part of the substrate contact part with the smallest inner diameter.

[0033] The substrate abutment portion may be formed contiguous with the bottommost portion of the coating liquid storage portion (the portion of the coating liquid storage portion closest to the second open end). In this case, the topmost portion of the substrate abutment portion may coincide with the bottommost portion of the coating liquid storage portion and may be the portion with the smallest inner diameter in the coating liquid attachment of the present invention.

[0034] The angle between the tapered surface of the substrate abutment portion and the axis of the coating attachment may be, for example, 30° or more and 75° or less. From the viewpoint of ensuring fixation of the honeycomb substrate during coating, this angle may be, for example, 35° or more, 40° or more, 45° or more, or 50° or more, and from the viewpoint of suppressing uncoated flow paths near the outer circumferential edge of the honeycomb substrate, the angle may be, for example, 70° or less, 65° or less, 60° or less, or 55° or less.

[0035] The coating attachment of the present invention has a substrate contact portion having a tapered surface whose inner diameter increases toward the second open end side (lower side). Therefore, when the coating attachment is placed on the honeycomb substrate, the diameter of the tapered surface closest to the first open end side (uppermost part) is configured to be smaller than the outer diameter of the honeycomb substrate.

[0036] In this case, the "protrusion width" defined as the difference between the radius of the honeycomb substrate and the radius of the top of the tapered surface may be set in consideration of the balance between the coating efficiency and the effect of the present invention. This "protrusion width" may be, for example, 0.3 mm or more, 0.5 mm or more, or 0.7 mm or more, and may be, for example, 2.0 mm or less, 1.8 mm or less, 1.5 mm or less, or 1.3 mm or less.

[0037] The inside (tapered surface) of the substrate abutment portion may be made of an elastic material. By making the tapered surface of the substrate abutment portion from an elastic material, the adhesion between the tapered surface of the substrate abutment portion and the honeycomb substrate is improved, and leakage of the coating liquid from that portion is suppressed. This suppresses adhesion of the coating liquid to a part of the outer skin of the honeycomb substrate.

[0038] The elastic material constituting the tapered surface of the substrate contacting portion may be one or more types selected from, for example, silicone rubber, fluororubber, and the like.

[0039] The material constituting the portion of the substrate contact portion other than the tapered surface may be made of a highly rigid material capable of maintaining the shape of the substrate contact portion. The material constituting the portion of the substrate contact portion other than the tapered surface may be, for example, a synthetic resin, a metal, or the like.

[0040] The substrate contact portion in the present invention may be, for example, made of a highly rigid material and may have a configuration in which a layer of an elastic material is formed on the inside of a cylindrical portion having an inner tapered surface.

[0041] <Connection part> As described above, the coating attachment of the present invention has a coating liquid storage section and a substrate contact section.

[0042] The coating attachment of the present invention further comprises, in addition to the coating liquid storage section and the substrate contact section, On the second opening end side from the substrate abutment portion, A connecting portion that coaxially surrounds the honeycomb substrate; and A substrate fixing portion for fixing the honeycomb substrate by coaxially surrounding the honeycomb substrate in that order.

[0043] The connecting portion in the coating attachment of the present invention has a structure that coaxially surrounds the honeycomb substrate. This connecting portion may have an opening for connecting the region of the outer peripheral surface of the honeycomb substrate near the substrate contact portion to the outside air.

[0044] Hereinafter, the advantage of the connection part having an opening will be described using an example in which the pressure around the coating attachment is atmospheric pressure. However, the pressure around the coating attachment of the present invention is not limited to atmospheric pressure, and the coating attachment may be used under pressurized or reduced pressure.

[0045] In the case where the coating attachment of the present invention does not have a connecting portion and a substrate fixing portion, when the coating attachment is placed on the upper end face of the honeycomb substrate, the region of the outer peripheral surface of the honeycomb substrate near the substrate abutment portion is naturally in contact with the outside air. Therefore, when the coating liquid is stored in the coating liquid storage portion of the coating attachment placed on one end face of the honeycomb substrate and sucked from the opposite end face of the honeycomb substrate, the pressure in the region of the outer peripheral surface of the honeycomb substrate near the substrate abutment portion is atmospheric pressure, and since the coating liquid stored in the coating liquid storage portion is sucked, the pressure becomes lower than atmospheric pressure. Therefore, the coating attachment of this embodiment is less likely to cause leakage of the coating liquid from the substrate abutment portion.

[0046] Next, consider a case where the coating attachment has a connecting portion and a substrate fixing portion. The honeycomb substrate to which the coating attachment of the present invention is applied may be made of ceramics having pores penetrating the partition walls. In this case, when the coating liquid is stored in the coating liquid storage portion of the coating attachment and sucked from the opposite end face of the honeycomb substrate, it is considered that the air on the outer peripheral surface side of the honeycomb substrate passes through the pores penetrating the partition walls and is sucked, and the pressure on the outer peripheral surface side of the honeycomb substrate becomes lower than atmospheric pressure. In that case, there is a concern that the coating liquid stored in the coating liquid storage portion will leak out beyond the substrate abutment portion into the reduced pressure side area and adhere to the outer skin of the honeycomb substrate.

[0047] However, if the connecting portion has an opening for connecting the region of the outer peripheral surface of the honeycomb substrate near the substrate abutment portion to the outside air, even if the coating liquid is stored in the coating liquid storage portion of the coating attachment and suction is performed from the opposite end face of the honeycomb substrate, outside air flows in from the opening, and the air pressure in the region of the honeycomb substrate near the substrate abutment portion is maintained at atmospheric pressure. Therefore, during suction, the coating liquid stored in the coating liquid storage portion is prevented from leaking beyond the substrate abutment portion and onto the outer peripheral surface side of the honeycomb substrate, and adhesion of the coating liquid to the outer skin of the honeycomb substrate can be prevented.

[0048] The openings of the connecting parts may extend in the circumferential direction of the connecting parts. In this case, the openings may extend discontinuously around the entire circumference of the connecting parts, or may extend continuously around the entire circumference of the connecting parts. If the openings of the connecting parts extend continuously around the entire circumference of the connecting parts, this is preferable in that the air pressure in the region near the base material abutment part of the honeycomb base material can be smoothly adjusted.

[0049] The width of the opening of the connecting portion (the opening width in the axial direction of the coating attachment) may be set appropriately, taking into consideration the intended degree of suction, the effectiveness of maintaining the air pressure in the area near the substrate abutment portion of the honeycomb substrate at atmospheric pressure, and the size of the coating attachment.

[0050] Such an opening may be formed, for example, by dividing the connecting portion into a portion (upper portion) closer to the first opening end than the opening and a portion (lower portion) closer to the second opening end than the opening, and connecting the two portions with a columnar portion. In this case, there may be a plurality of columnar portions, and these columnar portions may be present inside the opening and spaced apart from one another in the circumferential direction of the connecting portion. Here, if each columnar portion is configured to be entirely located inside the outer periphery of the connecting portion (closer to the axis of the coating attachment), the opening of the connecting portion can be configured to extend continuously around the entire circumference of the connecting portion.

[0051] The cross-sectional shape of the columnar portion cut in a direction perpendicular to the axial direction of the coating attachment may be, for example, a circle, an ellipse, a polygon, an arc, or a combination of these.

[0052] The material constituting the connecting portion may be made of a highly rigid material capable of maintaining the shape of the connecting portion. The material constituting the portion of the substrate abutment portion other than the tapered surface may be, for example, a synthetic resin, a metal, or the like. The material constituting the columnar portion may be the same as or different from the material constituting the connecting portion. The columnar portion may be a separate part from the other portions of the connecting portion, or may be integrally formed with the other portions of the connecting portion.

[0053] <Base material fixing part> The substrate fixing part in the coating attachment of the present invention has a function of coaxially surrounding the honeycomb substrate to fix the honeycomb substrate. To achieve this function, the substrate fixing part may have a substrate fixing part main body that coaxially surrounds the honeycomb substrate and supports the coating liquid storage part, the substrate abutment part, and the connecting part, and a balloon-shaped member that presses against the outer circumferential surface of the honeycomb substrate to fix it.

[0054] In order to effectively exert the supporting function, the substrate fixing part main body may have a flange part at the second open end of the coating attachment for fixing the coating attachment to a coating device, a coating table, etc. The substrate fixing part main body, including the flange part if present, may be composed of a highly rigid member.

[0055] The balloon-shaped member may be configured, for example, such that the upper end and the lower end are fixed between the substrate fixing part bodies, and the middle part can form a gap between the substrate fixing part body and the substrate fixing part body. According to this embodiment, air pressure, water pressure, or oil pressure is applied to the gap between the middle part of the balloon-shaped member and the substrate fixing part body to expand the balloon-shaped member toward the center, thereby pressing and fixing the outer circumferential surface of the honeycomb substrate.

[0056] The material constituting the substrate fixing portion main body may be made of a highly rigid material capable of maintaining its shape and fixing the honeycomb substrate. The material constituting this portion may be, for example, synthetic resin, metal, etc. The balloon-shaped member may be made of an elastic material in order to exert the function of pressing against the outer peripheral surface of the honeycomb substrate to fix it. The balloon-shaped member may be, for example, neoprene rubber, NBR, natural rubber, etc.

[0057] <Coating method> Another aspect of the present invention provides a method for coating a honeycomb substrate using the coating attachment of the present invention.

[0058] The coating method for a honeycomb substrate of the present invention includes the steps of: Attaching the coating attachment of the present invention to one end face of the honeycomb substrate (coating attachment attachment step); Placing and storing the coating liquid in a coating liquid storage portion of the coating attachment (coating liquid storage step); The coating liquid is sucked from the opposite end face of the honeycomb substrate (suction process). The method includes:

[0059] In the coating attachment mounting step, the coating attachment is mounted on one end face of the honeycomb substrate so that the tapered surface of the substrate contacting portion contacts the outer peripheral edge of the end face on one side of the honeycomb substrate. Here, the "overhang width" defined as half the difference between the diameter of the honeycomb substrate and the inner diameter of the uppermost portion of the tapered surface of the substrate contacting portion (the portion of the substrate contacting portion with the smallest inner diameter) is preferably larger from the viewpoint of preventing leakage of the coating liquid from the contacting portion, and is preferably smaller from the viewpoint of improving the efficiency of supplying the coating liquid to the flow path near the outer periphery of the honeycomb substrate. The "overhang width" may be appropriately set by a person skilled in the art after comprehensively considering the above.

[0060] In the coating liquid storage step, the coating liquid is placed and stored in the coating liquid storage portion of the coating attachment. The viscosity and amount of the coating liquid to be placed may be appropriately set by a person skilled in the art depending on the size of the honeycomb substrate and the desired coating length (the percentage of the substrate length to be coated).

[0061] In the suction step, the coating liquid is sucked from the opposite end face of the honeycomb substrate. The degree and time of this suction may be appropriately set by a person skilled in the art depending on the viscosity and amount of the coating liquid.

[0062] The coated honeycomb substrate can be dried and fired by a known method to form, for example, an exhaust gas purification catalyst device.

[0063] Specific Embodiments Hereinafter, examples of the configuration of the coating attachment of the present invention will be described with reference to the drawings.

[0064] FIG. 1 is a schematic cross-sectional view showing an example of the configuration of a coating attachment of the present invention.

[0065] The coating attachment (100) in FIG. 1 has an overall cylindrical shape and a first opening (A 11 ) is opened at the lower end, and a second opening (A 12 ) is open.

[0066] The coating attachment (100) has a first open end (A 11 ) side, and the second opening end (A 12 ) has a substrate contact portion (120).

[0067] The coating liquid storage section (110) is provided with a first opening end (A 11 ) side (upper side), the inner diameter remains the same for a while, but then it becomes larger toward the first open end (A 11 ) side, the inner diameter becomes larger.

[0068] The substrate contact section (120) is formed continuously with the lowermost portion of the coating liquid storage section (110), and the inside of the substrate contact section (120) is formed with a second opening end (A 12 ) side, the inner diameter becomes larger, forming a tapered surface (121).

[0069] FIG. 2 is a schematic cross-sectional view showing a state in which the coating attachment (100) shown in FIG. 1 is attached onto a honeycomb substrate (300).

[0070] FIG. 2 shows the state in which the tapered surface (121) of the substrate contact portion (120) is in contact with the outer peripheral edge of one end face of the honeycomb substrate (300). 1 )" is the diameter (d 300 ) and the inner diameter (d 120 ) is defined as half the difference between

[0071] 1 and 2, when placed on the upper end surface of the honeycomb substrate (300), the area of ​​the outer peripheral surface of the honeycomb substrate (300) near the substrate abutment portion (120) is always in contact with the outside air. Therefore, when coating is performed by the suction method using the coating attachment (100), the pressure in the area of ​​the outer peripheral surface of the honeycomb substrate (300) near the substrate abutment portion is kept at atmospheric pressure and is not reduced, so that leakage of the coating liquid from the substrate abutment portion (120) is unlikely to occur.

[0072] The coating attachment (200) in FIG. 3 has a generally cylindrical shape and a first opening (A 21 ) is opened at the lower end, and a second opening (A 22 ) is open.

[0073] The coating attachment (200) has a first open end (A 21 ) side, and the second opening end (A 22 ) side, and further, the second opening end (A 22 ) side, a connecting portion (230) and a substrate fixing portion (240) are provided.

[0074] The configurations of the coating liquid storage section (210) and the substrate contact section (220) of the coating attachment (200) are similar to the coating liquid storage section (110) and the substrate contact section (120) of the coating attachment (100) shown in Figures 1 and 2, and the substrate contact section (220) has a tapered surface (221).

[0075] The connecting portion (230) coaxially surrounds the honeycomb substrate and has a function of connecting the substrate abutting portion (220) and a substrate fixing portion (240) described below.

[0076] The connecting portion (230) of the coating attachment (200) is divided into an upper connecting portion portion (230a) on the first opening end side (upper side) and a lower connecting portion portion (230b) on the second opening end side (lower side), and the gap between them forms an opening portion (231). The upper connecting portion portion (230a) and the lower connecting portion portion (230b) are connected by a plurality of columnar portions (230c). These columnar portions (230c) are arranged inside the opening portion (231) at intervals from one another in the circumferential direction of the connecting portion (230), and are entirely located inside the outer periphery of the connecting portion (230) (closer to the axis of the coating attachment (200)). Due to such an arrangement of the multiple columnar portions (230c), the opening (231) of the gap between the upper connecting portion portion (230a) and the lower connecting portion portion (230b) extends continuously around the entire circumference of the connecting portion (230).

[0077] The substrate fixing portion (240) has a function of coaxially surrounding the honeycomb substrate and fixing the honeycomb substrate.

[0078] The substrate fixing part (240) of the coating attachment (200) has a substrate fixing part main body (241) and a balloon-shaped member (242), and further has a flange part (243).

[0079] The substrate fixing part main body (241) of the substrate fixing part (240) provides strength to the substrate fixing part (240) and the coating attachment (200), and has the function of holding the coating attachment (200) as a whole so that it can achieve its intended purpose.

[0080] The balloon-shaped member (242) is made of an elastic member, and when air pressure, water pressure, or oil pressure is applied between it and the substrate fixing part main body (241), it expands toward the center of the coating attachment (200) and has the function of pressing and fixing the outer peripheral surface of the honeycomb substrate.

[0081] In the coating attachment (200), the balloon-shaped member (242) is configured such that its upper end is sandwiched between the connecting portion upper part (230a) and the substrate fixing portion main body (241), and its lower end is sandwiched between the flange portion (243) and fixed, and a gap can be formed between the middle part and the substrate fixing portion main body (241). Also, in the coating attachment (200), the upper end of the balloon-shaped member (242) constitutes a part of the connecting portion lower part (230b). Such an embodiment is also included in the present invention.

[0082] The flange portion (243) may be used to secure the coating attachment (200) to a coating device, a coating table, etc. (neither of which are shown).

[0083] 4 shows the state in which the tapered surface (221) of the substrate abutment portion (220) abuts against the outer peripheral edge of one end face of the honeycomb substrate (300). Here, the balloon-shaped member (242) of the coating attachment (200) is shown expanding toward the center of the coating attachment (200) to press against and fix the outer peripheral surface of the honeycomb substrate (300).

[0084] In addition, "protrusion width (p 2 )" is the diameter (d 300 ) and the inner diameter (d 220 ) is defined as half the difference between

[0085] FIG. 5 shows a perspective view of the coating attachment (200).

[0086] When the coating attachment (200) shown in FIGS. 3 to 5 is placed on the upper end surface of the honeycomb substrate (300), the outer peripheral surface of the honeycomb substrate (300) is surrounded by the connecting portion (230) and the substrate fixing portion (240). However, the connecting portion (230) has an opening (231) that extends continuously around the entire circumference. Therefore, when coating is performed by the suction method using the coating attachment (200), outside air flows in from the opening (231), and the pressure in the region of the outer peripheral surface of the honeycomb substrate (300) near the substrate abutment portion is kept at atmospheric pressure and is unlikely to be reduced, so that leakage of the coating liquid from the substrate abutment portion (220) is suppressed. EXAMPLES

[0087] Examples 1 to 3 and Comparative Examples 1 and 2 Coating tests were carried out using a coating attachment having the general shape shown in Figure 2. The coating attachments used in each of the Examples and Comparative Examples were attachments whose angle (taper angle) between the tapered surface of the substrate contacting portion and the axis of the coating attachment, and whose connecting portion had or did not have an opening, were as shown in Table 1.

[0088] The materials constituting each part of the coating attachment used in the examples are as follows. Coating fluid storage section: Polyethylene resin Base material contact part Parts other than the tapered surface: Polyethylene resin Tapered surface: Silicon rubber sheet attached Base material fixing part Parts other than the flange: Polyethylene resin Flange: Stainless steel Balloon-shaped material: Neoprene rubber

[0089] The opening of the connection part in Examples 1 to 3 extended continuously around the entire circumference of the connection part, and the width of the opening (opening width in the axial direction of the coating attachment) was 1 mm. The "overhang width", defined as 1 / 2 the difference between the diameter of the honeycomb substrate and the inner diameter of the uppermost part of the tapered surface of the substrate abutment part, was 1.0 mm.

[0090] The coating test was performed by applying 80 g of coating liquid by suction to a cylindrical cordierite honeycomb substrate with a diameter of 80 mm and a length of 65 mm, and the presence or absence of uncoated flow paths and the amount of coating liquid (dry mass) attached to the outer skin of the honeycomb substrate were examined. Here, the substrate was replaced with a new one in sequence, and multiple coating tests were performed consecutively, and the average value of the multiple tests was used as the amount of coating liquid attached to the outer skin.

[0091] The coating liquid used in the coating test was a slurry-like coating liquid for forming a catalyst coating layer of an exhaust gas purification catalyst device, and had the following viscosity at 25°C. Shear rate 383s -1 Viscosity at: 180 mPa s Shear rate 3.83s -1 Viscosity at: 5,000 mPa s

[0092] The results are shown in Table 1.

[0093] [Table 1]

[0094] With reference to Table 1, the following can be seen:

[0095] In the coating tests of Comparative Examples 1 and 2, in which a coating attachment with no opening in the connecting portion was used, there were no uncoated flow paths, but the amount of coating liquid adhering to the outer shell was large.

[0096] In contrast, in the coating tests of Examples 1 to 3 using a coating attachment in which the substrate contact portion had a taper angle and the connecting portion had an opening, there were only a few or no uncoated flow paths, and the amount of coating liquid attached to the outer skin was small. In Example 3, some of the flow paths near the outer periphery of the honeycomb substrate were uncoated, but this was not to the extent that would cause a practical problem.

[0097] These coating tests verified that the coating attachment of the present invention achieves the intended purpose. [Explanation of symbols]

[0098] 100, 200 Coating attachment 110, 210 Coating liquid storage section 120, 220 Base material contact part 121, 221 Tapered surface 230 Connection section 230a Upper part of the connection part 230b Lower part of connection 230c Columnar part 231 Opening 240 Base material fixing part 241 Base material fixing part body 242 Balloon-shaped member 243 Flange 300 Honeycomb substrate A 11 , A 21 First opening A 12 , A 22 Second opening d 120 , d 220 Inside diameter of top of tapered surface d 300 Honeycomb substrate diameter p 1 , p 2 Overhang width

Claims

1. A coating attachment for applying a coating liquid to an inner wall of a flow path of a honeycomb substrate by a suction method, a substantially cylindrical shape having a first open end at one end and a second open end at the other end; a coating liquid storage portion at the first open end, and a substrate abutment portion for abutting against an outer peripheral edge of an end portion of the honeycomb substrate, the substrate abutment portion being located closer to the second open end than the coating liquid storage portion; the substrate contact portion has a tapered surface whose inner diameter increases toward the second opening end, On the second opening end side of the substrate abutment portion, A connecting portion coaxially surrounding the honeycomb substrate; and A substrate fixing portion for fixing the honeycomb substrate by coaxially surrounding the honeycomb substrate. in that order, and The connecting portion has an opening for connecting a region of the outer peripheral surface of the honeycomb substrate near the substrate abutment portion to outside air. Coating attachment.

2. 2. The coating attachment according to claim 1, wherein the opening of the connecting portion extends in a circumferential direction of the connecting portion.

3. 3. The coating attachment according to claim 2, wherein the opening in the connecting portion extends around the entire circumference of the connecting portion.

4. 4. The coating attachment according to claim 3, wherein a portion of the connecting portion closer to the first opening end than the opening and a portion of the connecting portion closer to the second opening end than the opening are connected inside the opening by a plurality of columnar portions spaced apart from one another in the circumferential direction of the connecting portion.

5. 5. The coating attachment according to claim 4, wherein a cross-sectional shape of the columnar portion cut in a direction perpendicular to the axial direction of the coating attachment is circular, elliptical, polygonal, or arc-shaped.

6. 6. The coating attachment according to claim 1, wherein the substrate contact portion is made of an elastic material.

7. 6. The coating attachment according to claim 1, wherein an angle between the tapered surface of the substrate contact portion and an axis of the coating attachment is 35° or more and 70° or less.

8. 6. The coating attachment according to claim 1, wherein the coating liquid storage section has an inner diameter that increases toward the first open end.

9. 6. The coating attachment according to claim 1, wherein the substrate fixing portion has a balloon-shaped member for pressing and fixing an outer peripheral surface of the honeycomb substrate.

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