HONEYCOMB STRUCTURE AND MANUFACTURING PROCESS OF A HONEYCOMB STRUCTURE

Abstract

Honeycomb structure, which includes the following: a columnar honeycomb structure body that has a porous partition wall such that it surrounds several cells running from a first end face to a second end face, and a circumferential coating layer formed from a circumferential coating material that is coated on at least a part of the circumference of the honeycomb structure body, wherein the peripheral coating layer has a printing area for printing on its surface, the print area has a brightness (L*) of 35 or more in the L*a*b* color space (CIE1976), which is defined by the International Commission on Illumination (CIE), and The printing area has a surface roughness Ra of 30 µm or less.

Description

BACKGROUND OF THE INVENTION Area of ​​the invention

[0001] The present invention relates to a honeycomb structure and a manufacturing method for a honeycomb structure. In particular, the present invention relates to a honeycomb structure having a circumferential coating layer with a display area for creating a display on its surface, and a manufacturing method for this. Description of the related area

[0002] To date, honeycomb structures made of ceramics have been used in widely adopted applications such as a catalyst support for cleaning vehicle exhaust gases, a purification filter for removing particulate matter from exhaust gas, and a heat storage unit for a combustion device. For example, a honeycomb structure contains a porous partition arranged to enclose multiple cells extending from a first end face (one end face) to a second end face (the other end face).

[0003] In recent years, there have been many instances where a honeycomb structure has been used for various purposes and tasks, and a large number of these structures are manufactured specifically for each application. Therefore, it is difficult to visually distinguish these honeycomb structures based on appearance and other characteristics. Once the honeycomb structure is manufactured, information required for subsequent product management (e.g., product management information) can be attached to it.

[0004] Specifically, product management information is printed directly onto the circumferential surface of the honeycomb structure using a printing technology such as laser marking. Consequently, it is possible to visually identify the honeycomb structure type, product number, and similar information directly from the outside. It should be noted that this product management information can include various pieces of data such as a product name, product number (model number), production number (batch number), production time, production location, and production line number.

[0005] Furthermore, to enable the combined display and management of several of the aforementioned product management metrics, the printing of two-dimensional codes, such as well-known barcodes and QR codes (registered trademark), onto the perimeter surfaces of the honeycomb structure is becoming increasingly common, instead of printing numbers or characters directly onto them. It should be noted that "printing" in this specification refers not only to the direct display of information such as characters and numbers, but also to the reproduction of various symbols, such as one-dimensional and two-dimensional codes, within a desired area.

[0006] The information relating to each honeycomb structure is easily obtained from the two-dimensional code printed on the circumferential surface using a reading device such as a barcode scanner. Consequently, an operator or inspector can verify the information, converted into recognizable characters and numbers, on a display screen or similar device.

[0007] As a result, it is possible, for example, to easily and immediately capture various types of information about the honeycomb structure during the period from the completion of its manufacture until it is installed as part of a passenger car or similar vehicle. For instance, it is possible to easily record the movement route, the quantity in stock from the moment the honeycomb structure is transported to a warehouse until it is actually used, the storage period, the storage location, the current condition, and similar data for each honeycomb structure. This enables traceability of information for each honeycomb structure and allows for the immediate capture and use of the aforementioned information. Therefore, printing product information and similar data on the perimeter surface of the honeycomb structure is extremely useful for product management.

[0008] Printing product information, such as a two-dimensional code, onto the circumferential surface of the honeycomb structure is carried out, for example, by a known printing process and a known printing technique such as laser marking or inkjet printing.

[0009] For example, a technique has been proposed in which a peripheral coating layer containing laser color development raw material powder is provided on the peripheral surface of the honeycomb structure and laser marking is carried out on the surface of the peripheral coating layer (see patent document 1).

[0010] Further prior art is also known from patent documents 2 to 4. [Patent Document 1] JP 2016- 055 282 A [Patent document 2] US 2017 / 0 002 205 A1 [Patent document 3] US 2006 / 0 216 467 A1 [Patent document 4] US 2018 / 0 273 432 A1 SUMMARY OF THE INVENTION

[0011] Traditionally, laser marking or inkjet printing, as mentioned above, was often used as a method for printing onto the circumferential surface of the honeycomb structure. However, with each method, the printed characters and the like were difficult to read. Specifically, a symbol, such as a two-dimensional code, must be decoded by a reading device, and if reading by the device is difficult, capturing the information becomes extremely challenging. For example, printing characters, numbers, and the like might allow predictions about the information to be made based on the appearance of the printed characters. However, if it is difficult for the reading device to read a symbol, such as a two-dimensional code, it may be impossible to capture any information at all.It must be noted that, although the description was given with the effect that predictions can be made about the information regarding the printing of characters, numbers and the like, a doubt remains regarding the accuracy of the information obtained, such that it is also necessary to carry out the printing of characters, numbers and the like with good legibility.

[0012] The present invention was developed with regard to the problems of the prior art. The present invention provides a honeycomb structure having a circumferential coating layer with a printing area for printing on its surface. In particular, the present invention provides a honeycomb structure that can improve the legibility of characters and symbols printed in the printing areas of the circumferential coating layers, and a manufacturing method for this.

[0013] According to the present invention, a honeycomb structure and a manufacturing process for it are created as follows.

[0014] [1] A honeycomb structure comprising: a columnar honeycomb structure body having a porous partition arranged to surround several cells extending from a first end face to a second end face, and a circumferential coating layer formed from a circumferential coating material that is coated on at least a part of the circumference of the honeycomb structure body, wherein the peripheral coating layer has a printing area for printing on its surface, the print area has a brightness (L*) of 35 or more in the L*a*b* color space (CIE1976), which is defined by the International Commission on Illumination (CIE), and The printing area has a surface roughness Ra of 30 µm or less.

[0015] [2] The honeycomb structure according to [1], wherein the circumferential coating layer contains several aggregate particles and a neck material for connecting the aggregate particles together.

[0016] [3] The honeycomb structure according to [1] or [2], wherein the cells in the honeycomb structure body are sealed by sealing sections at one end either on the side of the first end face or on the side of the second end face of the honeycomb structure body.

[0017] [4] The honeycomb structure according to one of [1] to [3], wherein the circumferential coating layer is arranged such that it surrounds the perimeter of the honeycomb structure body.

[0018] [5] The honeycomb structure according to [1] to [4], wherein the peripheral coating layer contains a laser color development component which develops a color different from the original color by means of a laser.

[0019] [6] The honeycomb structure according to one of [1] to [5], wherein the circumferential coating layer is formed from a porous material.

[0020] [7] The honeycomb structure according to one of [1] to [6], wherein the content of at least one component of silicon carbide, metallic silicon, magnesium oxide and aluminium oxide in a part forming the printing area of ​​the circumferential coating layer is 20 wt% or more in relation to 100 wt% of the components of the part.

[0021] [8] The honeycomb structure according to one of [1] to [7], where the printing area serves to print an information code.

[0022] [9] The honeycomb structure according to [8], where the information code is a two-dimensional code.

[0023]

[10] The honeycomb structure according to [9], wherein a point size of the two-dimensional code is in the range of 0.3 mm to 1.0 mm.

[0024]

[11] A manufacturing process for a honeycomb structure according to [1] to

[10] , comprising coating the peripheral coating material on at least a part of the circumference of the honeycomb structure body, wherein the peripheral coating material contains as aggregate particles at least one selected from the group consisting of fine silicon carbide particles, aluminum oxide particles, cordierite particles, titanium oxide particles and aluminum nitride particles having an average particle diameter in the range of 1 to 5 µm, wherein the peripheral coating material is manufactured such that a shear stress (Pa) measured by a rotational viscometer at a rotational speed of 2.0 s -1 Measured at a temperature of 25 °C, the pressure is in the range of 20 to 250 Pa.

[0025] The honeycomb structure of the present embodiment can improve the readability of characters and symbols printed in the printed areas of the circumferential coating layers. In particular, when, for example, a symbol such as a two-dimensional code is printed, a reading error by the reading device is unlikely, and more reliable information can be acquired. The manufacturing process of the honeycomb structure of the present invention can conveniently produce the honeycomb structure of the present invention as described above. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a perspective view that schematically shows an embodiment of a honeycomb structure of the present invention. Fig. Figure 2 is a perspective view that schematically shows another embodiment of a honeycomb structure of the present invention. DESCRIPTION OF PREFERRED EXECUTION FORMS

[0026] The following describes embodiments of the present invention. However, the present invention is not limited to the following embodiments. Naturally, changes, modifications, and the like can be made to the following embodiments based on the usual knowledge of a person skilled in the art, without departing from the spirit of the present invention. (1) Honeycomb structure:

[0027] One embodiment of the honeycomb structure of the present invention is a honeycomb structure 100, as shown in Fig. 1 is shown. Fig. Figure 1 is a perspective view schematically showing an embodiment of the honeycomb structure of the present invention. The honeycomb structure 100 comprises a honeycomb structure body 10 and a circumferential coating layer 20 arranged around the perimeter of the honeycomb structure body 10.

[0028] The honeycomb structure 10 consists of column-shaped elements that have a porous partition 1. The partition 1 is arranged such that it surrounds several cells 2 that extend from a first end face 11 to a second end face 12 of the honeycomb structure 10. In the present invention, the cell 2 means the space enclosed by the partition 1.

[0029] The circumferential coating layer 20 is formed from a circumferential coating material that is applied to at least a portion of the circumference of the honeycomb structure body 10. In the honeycomb structure 100, which is in Fig.As shown in Figure 1, the honeycomb structure 10 has a circumferential wall 3 arranged such that it surrounds the partition 1 at its periphery. The circumferential coating layer 20 is formed from a circumferential coating material that is applied to the surface of the circumferential wall 3 of the honeycomb structure 10. It should be noted that the honeycomb structure 10 does not necessarily have to have a circumferential wall 3 at its periphery. In such cases, the circumferential coating layers 20 can be arranged directly on the periphery of the partition 1, which is arranged in a grid pattern forming the honeycomb structure 10.

[0030] The circumferential coating layer 20 can be arranged on a portion of the circumference of the columnar honeycomb structure body 10, or it can be arranged to cover the entire circumference of the columnar honeycomb structure body 10. Preferably, the circumferential coating layer 20 is arranged to cover the entire circumference of the honeycomb structure body 10 and to form an outer wall for the interface between the honeycomb structure 10 and the outer surface. That is, it is preferred that the circumferential coating layer 20 is arranged to surround the circumference of the honeycomb structure body 10.

[0031] The circumferential coating layer 20 has a printing area 21 for printing on its surface. The printing area 21 is an area for printing, for example, product management information onto the honeycomb structure 100. The size of the printing area 21 is not particularly limited and can be suitably determined in accordance with the size of the imprint on the honeycomb structure 100. For example, the size of the printing area 21 is preferably 80 mm in one direction and 60 mm in the direction perpendicular to that one direction. Additionally, the area of ​​the printing area 21 is preferably 4500 to 5500 mm². 2 . The total surface area of ​​the peripheral coating layer 20 can be used as the printing area 21.

[0032] The printed area 21 of the peripheral coating layer 20 has a brightness (L*) of 35 or higher in the L*a*b* color space (CIE1976), as defined by the International Commission on Illumination (CIE). Furthermore, the printed area 21 in the peripheral coating layer 20 has a surface roughness Ra of 30 µm or less. This configuration improves the readability of characters and symbols printed in the printed area 21 of the peripheral coating layer 20. In particular, when a symbol such as a two-dimensional code is printed, a reading error by the reading device is less likely, and more reliable information can be captured.It should be noted that “the brightness (L*) of the print area 21 of the peripheral coating layer 20 is 35 or more” means that the peripheral coating layer 20 has a print area 21 of a specified area (surface) with a brightness (L*) of 35 or more.

[0033] The brightness (L*) of print area 21 is an L* value in the L*a*b* color space (CIE 1976), defined by the International Commission on Illumination (CIE). The L* value is a value between 0 and 100 that indicates the brightness of the color. The closer it is to 0, the darker it is; the closer it is to 100, the lighter it is. The a* value represents the red / green position of the color, with a positive value indicating the red side and a negative value indicating the green side. The b* value represents the yellow / blue position of the color, with a positive value indicating the yellow side and a negative value indicating the blue side. The brightness (L*) of print area 21 can be measured by a spectrocolorimeter. A spectrocolorimeter can be, for example, a... For example, a “CM-2600d / 2500d (trade name)” manufactured by Konica Minolta Japan, Inc. can be used.The brightness (L*) of the print area 21 can be measured according to the procedure defined by the International Commission on Illumination (CIE) or the procedure according to the procedure (e.g. JIS Z 8781-4 and JIS Z 8781-5 of the Japanese Industrial Standard).

[0034] While the theoretical upper limit of the brightness (L*) is 100, as described above, a fixed upper limit of the brightness (L*) of the printed area 21 of the peripheral coating layer 20 can be, for example, 80. Therefore, the brightness (L*) of the printed area 21 is preferably in the range of 35 to 80. A lower limit of the brightness (L*) of the printed area 21 is preferably 40, more preferably 45, and particularly preferably 50.

[0035] In the honeycomb structure 100, the circumferential coating layer 20 has a surface roughness Ra of the printing area 21 of 30 µm or less. This configuration improves the readability of characters and symbols printed in the printing area 21 of the circumferential coating layer 20. In particular, when a symbol such as a two-dimensional code is printed, a reading error by the reading device is unlikely, and more reliable information can be captured.

[0036] The surface roughness Ra (the arithmetic mean of the roughness) of the printed area 21 can be calculated using a contact-type surface roughness measuring device. For example, a device for measuring surface roughness Ra, such as the "Form Talysurf S5K (trade name)", manufactured by Taylor Hobson, can be used.

[0037] The surface roughness Ra of the printed area 21 can be adjusted, for example, by modifying the viscosity of the circumferential coating material applied to the perimeter of the honeycomb structure body 10. The circumferential coating material can be prepared by adding a binder to the aggregate particles, water, various organic binders, and the like to the aggregate particles forming the circumferential coating layer 20. Currently, the viscosity of the circumferential coating material can be adjusted by changing the amount of water or organic binder added. The binder acts as a neck material in the circumferential coating layer 20. The organic binder provides a suitable viscosity, dimensional stability, and water retention for the application of the circumferential coating material.The viscosity of the peripheral coating material can be defined by measuring the shear stress (Pa) of the peripheral coating material. The shear stress (Pa) is a value determined by a rotational viscometer at a rotational speed of 2.0 s. -1 The surface roughness (Ra) of the printed area is measured at a temperature of 25 °C. The peripheral coating material is preferably manufactured such that the shear stress (in other words, the viscosity) is in the range of 20 to 250 Pa, and particularly preferably in the range of 50 to 150 Pa. If the shear stress of the peripheral coating material is less than 20 Pa or exceeds 250 Pa, the surface roughness Ra of the printed area is likely to exceed 2130 µm.

[0038] Preferably, the circumferential coating layer 20 has a surface roughness Ra of 30 µm or less over the entire surface containing the printing area 21.

[0039] The position of the printing area 21 in the peripheral coating layer 20 is not particularly restricted. For example, it is preferred that the printing area 21 is arranged on the surface of the peripheral coating layer 20 in order to be closer to the side of the end face of either the first end face 11 or the second end face 12.

[0040] It is preferred that the circumferential coating layer 20 contains several aggregate particles and a neck material for connecting the aggregate particles to one another. It is further preferred that the aforementioned aggregate particles contain at least one element selected from the group consisting of fine silicon carbide particles, aluminum oxide particles, cordierite particles, titanium oxide particles, and aluminum nitride particles, having a particle diameter in the range of 1 to 5 µm.

[0041] The brightness (L*) of the peripheral coating layer 20 is reduced by at least one element selected from the group described above. For example, fine silicon carbide particles, which have a particle diameter in the range of 1 to 5 µm, tend to be closer to white in color compared to coarse silicon carbide particles, which have a larger particle diameter. For example, the coarse silicon carbide particles are relatively black, and the fine silicon carbide particles, which have a particle diameter in the range of 1 to 5 µm, are relatively gray. Additionally, the aluminum oxide particles are relatively white. The cordierite particles are a relatively pale grayish-yellow. The titanium oxide particles and the aluminum nitride particles are relatively white.As described above, the brightness value (L*) of the print area 21 of the peripheral coating layer 20 can be increased (e.g., to 35 or more) by adjusting the proportion of at least one element selected from the group described above as an aggregate particle in the peripheral coating material. If the brightness (L*) of the print area 21 can be adjusted to 35 or more by incorporating a suitable amount of the aggregate particles mentioned above, the peripheral coating material can further comprise, for example, coarse silicon carbide particles with a particle diameter greater than 5 µm, or materials other than the aggregate particle. The other materials described above can include, for example, mullite, zirconium oxide, zirconium phosphate, silicon nitride, ceramic fibers, grinding slurry, or powdered honeycomb structure based on silicon carbide.

[0042] The peripheral coating layer 20 can contain a laser color development component that, when exposed to a laser, develops a color different from the original color. For example, the laser color development component can contain silicon carbide, titanium oxide, aluminum nitride, and the like. By incorporating such a laser color development component, it is possible to satisfactorily achieve the desired printing on the peripheral coating layer 20 by irradiating the peripheral coating layer 20 with a laser. In particular, each of the laser color development components mentioned above can excellently shape the color development properties during laser irradiation (i.e., the printability by a laser). For example, by irradiating the printing area 21 of the peripheral coating layer 20 with a laser such as…With an infrared laser of a predetermined wavelength, only the irradiated part that is illuminated by the laser changes color to black.

[0043] The peripheral coating layer 20 need not contain the laser color development component mentioned above. For example, if the peripheral coating layer 20 does not contain a laser color development component, printing into the print area 21 can be carried out by a process such as inkjet printing.

[0044] In the part forming the printing area 21 of the peripheral coating layer 20, it is preferred that the proportion of at least one component comprising silicon carbide, metallic silicon, magnesium oxide, and aluminum oxide is 20 wt% or more per 100 wt% of the component. Additionally, one of the preferred configurations is that the component comprising silicon carbide, metallic silicon, magnesium oxide, and aluminum oxide described above is the component having the highest proportion in the part forming the printing area 21. Hereinafter, a component having the highest proportion may be referred to as the "main component." For example, even if each of the four components mentioned above has a proportion of less than 20 wt%, if the proportion of one of the four components mentioned above is the highest in the part forming the printing area 21, that component is a main component.

[0045] In the honeycomb structure 100 of the present embodiment, it is preferred that the printing performed in the printing area 21 is an information code. It is more preferred that the aforementioned information code is a two-dimensional code. According to the honeycomb structure 100 of the present embodiment, even if the information code is a two-dimensional code, reading errors by the reading device are less likely to occur, and more reliable information can be captured. The dot size of the two-dimensional code is not particularly limited, but is preferably, for example, in the range of 0.3 to 1.0 mm.

[0046] The thickness of the peripheral coating layer 20 is not particularly limited. For example, the thickness of the peripheral coating layer 20 is preferably in the range of 0.05 to 4.0 mm. If the thickness is less than 0.05 mm, the honeycomb structure body 10 may be exposed. Conversely, if the thickness exceeds 4.0 mm, the honeycomb structure 10 may deviate from a dimensional tolerance, and the pressure loss may increase.

[0047] The thickness of the partition 1 forming the honeycomb structure 10 is not particularly limited. For example, from the standpoint of ease of manufacture, the thickness of the partition 1 is preferably in the range of 0.20 to 0.50 mm and more preferably in the range of 0.25 to 0.45 mm. If the thickness is less than 0.20 mm, the strength of the honeycomb structure 10 may be reduced, and if the thickness exceeds 0.50 mm, the pressure drop may increase when the honeycomb structure 10 is used as a filter. The thickness of the partition 1 is an average value determined by microscopic examination of the axial cross-section.

[0048] The porosity of the partition 1 is preferably in the range of 30 to 70% and more preferably in the range of 40 to 65%. The porosity of the partition 1 is a value that is measured by the mercury injection method. The porosity of the partition 1 can be measured, for example, using Autopore 9500 (trade name), which is manufactured by Micromeritics Co. The porosity can be measured by cutting out a portion of the partition 1 to obtain a test specimen and using the test specimen. If the porosity of the partition 1 is less than 30%, the pressure drop may increase when the honeycomb structure 100 is used as an element for cleaning exhaust gas. If the porosity of the partition 1 exceeds 70%, the strength of the honeycomb structure 100 may deteriorate.

[0049] The shape of the cells 2 formed in the honeycomb structure 10 is not particularly restricted. For example, the cells 2 in a section perpendicular to the direction of extension of the cells 2 can have various shapes, such as polygons, circles, and elliptical shapes. Examples of polygon shapes include triangles, quadrilaterals, pentagons, hexagons, and octagons. The shape of the cells 2 is preferably a triangle, quadrilateral, pentagon, hexagon, or octagon. Regarding the shape of the cells 2, all cells 2 can have the same shape, or the cells 2 can have different shapes. For example, although not shown, quadrilateral and octagonal cells can be combined. Regarding the size of the cells 2, all cells 2 can have the same size, or the cells 2 can have different sizes.For example, although this is not shown, some of the multiple cells may be larger and other cells may be relatively smaller.

[0050] The cell density of cell 2, defined by the partition 1, is not particularly limited. For example, the cell density preferably lies in the range of 5 to 63 cells per cm². 2 and more strongly preferred in the range of 31 to 54 cells per cm² 2 .

[0051] The method for forming the circumferential coating layer 20 on the circumference of the honeycomb structure body 10 is not particularly restricted, and a conventionally known method can be used. Examples of the method include coating a circumferential coating material prepared to have a desired viscosity, e.g., by the following method or the like. This involves arranging a honeycomb structure body on the rotary table and rotating it while the circumferential coating material is dispensed from the blade-shaped coating nozzle, and pressing the coating nozzle along the circumference of the honeycomb structure body to coat it. In this way, the circumferential coating material can be coated with a uniform thickness.

[0052] The overall shape of the honeycomb structure 100 is not particularly restricted. For example, the overall shape of the honeycomb structure 100, which is in Fig.Figure 1 shows a columnar shape, with the first end face 11 and the second end face 12 being circular. Additionally, although not shown, the overall shape of the honeycomb structure can be a columnar shape, with the first and second end faces being essentially circular, such as an elliptical, racetrack, or oval shape. Furthermore, the overall shape of the honeycomb structure can be a prismatic shape, with the first and second end faces being polygons, such as a square or a hexagon.

[0053] Although the material forming partition 1 is not particularly restricted, at least one material selected from the group of materials below is preferred from the standpoint of strength, thermal resistance, durability, and the like. The group of materials includes silicon carbide, a silicon-silicon carbide composite, silicon nitride, cordierite, mullite, aluminum oxide, spinel, a silicon carbide-cordierite composite, lithium aluminum silicate, aluminum titanate, and Fe-Cr-Al-based metals. Among these, silicon carbide or a silicon-silicon carbide composite is more preferred. A silicon-silicon carbide composite is a composite material containing silicon carbide (SiC) as an aggregate and silicon (Si) as a binder.

[0054] In the honeycomb structure 100, the partition 1, which defines several cells 2, can be loaded with a catalyst. Loading the catalyst onto the partition 1 means that the catalyst is coated on the surface of the partition 1 and on the inner wall of a pore formed on the partition 1. With this structure, CO, NOx, HC, and the like in an exhaust gas can be rendered harmless through a catalytic reaction. Additionally, when the honeycomb structure 100 is used as an exhaust gas purification filter, the oxidation of suspended solids such as deposited soot can be accelerated.

[0055] Then, a further embodiment of the honeycomb structure of the present invention is described with reference to Fig. 2 described. Fig. Figure 2 is a perspective view schematically showing another embodiment of the honeycomb structure of the present invention. The honeycomb structure 200, which is shown in Fig.Figure 2 shows the so-called honeycomb structure 200 of a segmented structure. The honeycomb structure 200 comprises a honeycomb structure body 40 of a segmented structure and a circumferential coating layer 50, which is arranged such that it surrounds the perimeter of the honeycomb structure body 40.

[0056] The honeycomb structure 40 contains several honeycomb segments 34 and a bonding layer 36. The honeycomb segment 34 has a porous partition 31 arranged such that it surrounds several cells 32 extending from the first end face 41 to the second end face 42. The honeycomb segment 34 also has an outer segment wall on its circumferential part such that the overall shape is configured, for example, as a prismatic shape.

[0057] In the multiple honeycomb segments 34, the side surfaces of the honeycomb segments 34 are connected to one another by means of a bonding layer 36. Thus, the connected body in which the multiple honeycomb segments 34 are connected by means of the bonding layer 36 is the honeycomb structure body 40 within the honeycomb structure 200. The circumferential coating layer 50 is arranged such that it surrounds the perimeter of the honeycomb structure body 40. The circumferential coating layer 50 forms an outer wall for creating the boundary between the honeycomb structure 200 and the outer surface.

[0058] In cell 32 of each honeycomb segment 34, one end of the side of the first end face 41 or the side of the second end face 42 is sealed with a sealing section 35. That is, the sealing section 35 is arranged at the open end of the first end face 41 of the designated cell 32 and at the open end of the second end face 42 of the remaining cells 32 except the designated cell 32 in each honeycomb segment 34. The honeycomb structure 200 can be suitablely used as an exhaust gas purification filter to remove suspended particles from exhaust gas. Although Fig. Figure 2 shows the example of the case in which one end of cell 32 is sealed with the sealing section 35. The sealing section 35 is not an essential component and is an optional component when the honeycomb structure 200 is used as an exhaust gas purification filter. For example, the honeycomb structure 100, which is shown in Fig.As shown in Figure 1, one end of cell 2 is sealed with a sealing section (which is not shown).

[0059] In the honeycomb structure body 40, a portion of its circumferential part can be processed by grinding or the like, depending on the overall shape of the honeycomb structure 200. For example, among the multiple honeycomb segments 34 that form the honeycomb structure bodies 40, the honeycomb segment 34 that is arranged on the outer circumference of the honeycomb structure body 40 such that it is in contact with the circumferential coating layer 50 is referred to as the "circumferential segment," and among the multiple honeycomb segments 34, the honeycomb segment 34 other than the circumferential segment is referred to as the "central segment." The shape of the central segment is preferably a prismatic shape, in which the cut shape perpendicular to the axial direction of the central segment is quadrilateral. With regard to the shape of the circumferential segment, a portion of the prismatic shape can be processed by grinding or the like, depending on the overall shape of the honeycomb structure 200, and examples of the shape before processing include a triangle and a quadrilateral.

[0060] The material forming honeycomb segment 34 is not particularly restricted. For example, at least one material is preferred that is selected from the group of materials that can form the partition 1 (see Fig. 1) forms, in one embodiment (of the honeycomb structure 100, which is in Fig. 1 is shown) of the present invention.

[0061] The partition 31 and the cell 32 in honeycomb segment 34 are preferably similar to the partition 1 (see Fig. 1) and cell 2 (see Fig. 1) in one embodiment (of the honeycomb structure 100, which is in Fig. 1 shown) of the present invention configured, except that the honeycomb structure body 40 is a segmented structure.

[0062] The material of the binder layer 36 is not particularly restricted. For example, the material of the binder layer 36 can be a material in a conventionally known honeycomb structure or a segmented structure.

[0063] The material of the sealing section 35 is not particularly limited. The material of the sealing section 35 is preferably, for example, a material similar to that of the material illustrated as forming the honeycomb segment 34. (2) Manufacturing process of the honeycomb structure:

[0064] The manufacturing process for the honeycomb structure of this embodiment is not particularly limited and it can be produced, for example, by the following method. First, a kneaded plastic material is prepared to create a honeycomb structure body. The kneaded material for the honeycomb structure body can be prepared by adding, as appropriate, an additive such as a binder and water to a raw material powder selected from the above-mentioned suitable partition materials.

[0065] The kneaded material obtained in this way is then extruded to create a honeycomb-shaped body with a partition wall arranged to surround multiple cells. When a honeycomb structure is produced within a segmented structure, several prismatically shaped honeycomb bodies are created for each honeycomb segment.

[0066] The resulting honeycomb mold is then dried, for example, with microwaves and hot air. Open ends of the cells are then sealed as needed. A material similar to that used to manufacture the honeycomb mold can be used for sealing the open cell ends. The sealed portion of an open cell end forms a sealing section within the honeycomb structure. It should be noted that the honeycomb mold can be dried again after the open cell ends have been sealed.

[0067] The honeycomb mold is then fired to obtain a fired honeycomb body. When a honeycomb structure is produced, as in Fig. As shown in Figure 1, the resulting fired honeycomb body is the honeycomb structure body 10. When a honeycomb structure 200 is produced, as in Fig.As shown in Figure 2, the resulting fired honeycomb body consists of honeycomb segments 34. The firing temperature and firing atmosphere vary depending on the raw materials, and experts will be able to select the firing temperature and firing atmosphere that are optimal for the chosen materials.

[0068] When a honeycomb structure of a segmented structure is produced, several honeycomb segments are joined together using a binding material. Then, the perimeter of a joined element of the honeycomb segment is processed by grinding or similar methods to achieve the desired shape. As described above, the honeycomb structure body of the segmented structure can be created. When a honeycomb structure of 100 is produced, as described in Fig.As shown in Figure 1, the circumferential part of the resulting fired honeycomb body is subjected to grinding or the like in order to remove the circumferential wall 3 of the fired honeycomb body (see Figure 1). Fig. 1) The shape of the fired honeycomb body can be adjusted to a desired shape by performing such grinding. For example, if the shape of the fired honeycomb body exhibits a deformation or the like due to firing shrinkage or the like during firing, it is possible to reshape the fired honeycomb body by grinding its circumference. The grinding process is not particularly limited and can be carried out in accordance with a method used in the production of a conventionally known honeycomb structure that has circumferential coating layers.

[0069] Then, a peripheral coating material is prepared to create a peripheral coating layer. The peripheral coating material is preferably prepared by mixing aggregate particles made from ceramics with a binder for bonding the aggregate particles together, as applicable, an organic binder, a dispersing agent, a surfactant, a dispersion medium, a pore-forming agent, clay, and the like.

[0070] It is further preferred that the aggregate particles contain at least one selected from the group consisting of fine silicon carbide particles, aluminum oxide particles, cordierite particles, titanium oxide particles, and aluminum nitride particles, having an average particle diameter in the range of 1 to 5 µm. If fine silicon carbide particles with an average particle diameter in the range of 1 to 5 µm are used, coarse silicon carbide particles with an average particle diameter greater than 5 µm (e.g., an average particle diameter in the range of 10 to 30 µm) can be used together. The brightness (L*) of the peripheral coating layers formed by the peripheral coating material can be adjusted to be 35 or higher by adjusting the material selection of the aggregate particles and their mixing ratio.It is preferred that the aggregate particles are uniformly distributed. The average particle diameter of the aggregate particles is a value determined by particle size measurement using the laser diffraction / laser scattering method.

[0071] The binder is a necking material that binds the aggregate particles together. Examples of the binder include colloidal silicon dioxide. When mixing the circumferential coating material, if the sum of the aggregate particles and the binder is adjusted to 100% by mass, the proportion of the binder in the mixture is preferably 20 to 35% by mass and more preferably 25 to 30% by mass.

[0072] It is preferred that the binder contains a colloidal oxide in which a polymer is dispersed. By incorporating a colloidal oxide in which a polymer is dispersed, shrinkage of a peripheral coating material during drying can be suppressed. For example, it is more preferred to use colloidal silicon dioxide than colloidal oxide.

[0073] The viscosity of the peripheral coating material can be determined by measuring its shear stress (Pa). The shear stress is preferably in the range of 20 to 250 Pa. If the shear stress is less than 20 Pa or more than 250 Pa, the surface roughness (Ra) of the printed area is likely to exceed 30 µm. The shear stress of the peripheral coating material can be adjusted by adding an organic binder, a dispersion medium, or similar additive.

[0074] The dispersion medium may contain water. Examples of suitable organic binders include methylcellulose, hydroxypropoxymethylcellulose, carboxylmethylcellulose, polyvinyl alcohol, and the like.

[0075] Examples of suitable dispersants include polyethylene glycol, polyvinyl alcohol, polyoxyethylene alkyl ethers, polyethylene glycol fatty acid esters, and the like. Examples of suitable clays include a clay mineral such as bentonite and montmorillonite.

[0076] Then, a peripheral coating material is applied to the circumference of the produced honeycomb structure to create a peripheral coating layer. The coating process for the peripheral coating material is not particularly limited, and the coating can be carried out according to a method used in the production of a conventionally known honeycomb structure having a peripheral coating layer. As described above, the honeycomb structure of the present invention can be produced.

[0077] Examples of the peripheral coating process may include the following procedure: A honeycomb structure body (in other words, a fired honeycomb body as described above) is placed on the turntable and rotated. While the peripheral coating material is dispensed from the blade-shaped coating nozzle, the coating nozzle is pressed along the circumference of the honeycomb structure body to apply the coating. In this way, the peripheral coating material can be applied with a uniform thickness.

[0078] If the circumferential surface of the honeycomb structure has been ground and the perimeter wall removed, the perimeter coating material should be applied to the entire circumferential surface of the honeycomb structure to form a perimeter coating. Conversely, if the perimeter wall is present on the circumferential surface of the honeycomb structure, or if part of the perimeter wall has been removed, the perimeter coating material can be applied only partially to form the perimeter coating. Of course, the perimeter coating material can also be applied to the entire perimeter surface of the honeycomb structure to form the perimeter coating. The perimeter coating described above is intended to be the perimeter coating layer.

[0079] The method for drying the coated peripheral coating material (i.e., the undried peripheral coating material) is not particularly restricted. For example, from the standpoint of preventing drying cracks, a suitable method is to remove moisture and organic substances by drying at room temperature if necessary and then holding in an electric melting furnace at 400 to 700 °C for 10 minutes or more.

[0080] The resulting honeycomb structure has a printable area where the brightness (L*) in the L*a*b* color space (CIE 1976), defined by the International Commission on Illumination (CIE), is 35 or higher in the peripheral coating layer formed from the peripheral coating material. Printing can be performed by irradiating the printable area of ​​the peripheral coating layer with a laser to develop a color-developing component (e.g., silicon carbide or titanium oxide) contained within the peripheral coating layer. Examples of printed data include an information code, such as a two-dimensional code. Suitable examples of laser beams used for laser printing include a CO2 laser, a YAG laser, and a YVO4 laser. The laser's state for emitting the laser beam can be appropriately selected depending on the type of laser to be used.For example, when using a CO2 laser, marking is preferably performed at a power level of 15 to 25 W and a scanning speed of 400 to 600 mm / s. Marking in this way causes the irradiated part to develop a dark color, such as black to green, and the contrast with the unirradiated part is extremely good due to the color development. If the honeycomb structure is loaded with the catalyst, even after printing with the laser described above, the printed part is not degraded and the print remains clearly legible even after catalyst loading. The catalyst loading process is not particularly limited and can be carried out according to the catalyst loading process used in the conventional manufacturing process for the honeycomb structure. Examples

[0081] The present invention will be described in more detail below by means of examples; however, the present invention is in no way limited by these examples. (Example 1)

[0082] To the silicon carbide-metallic silicon raw material powder, which was mixed in such a way that the composition after firing was silicon carbide, the following were added: metallic silicon = 80:20, a forming aid, a pore former and water, mixed and kneaded to produce a kneaded material.

[0083] The resulting kneaded material was then shaped using a vacuum extruder to produce 16 pieces of the honeycomb body, which has a square prism shape.

[0084] The resulting honeycomb-shaped body was then dried using dielectric high-frequency heating and then dried using a hot air dryer at 120 °C for 2 hours.

[0085] Then, after drying, a sealing section was formed on the honeycomb mold. Specifically, first, one end face of the honeycomb mold was masked to cover a predetermined cell. One end of the masked end face was then immersed in a sealing slurry containing a sealant to form a sealing section, and the open end of the remaining unmasked cells was filled with the sealing slurry. Then, a second end face of the honeycomb mold was masked to cover the remaining cells in a manner similar to that described above, and the open end of the predetermined unmasked cell was filled with a sealing slurry.

[0086] The honeycomb mold, on which the sealing section was formed, was degreased and fired to obtain honeycomb segments. The degreasing condition was set to 5 hours at 400 °C and the firing condition to 1.5 hours at 1450 °C under an argon atmosphere.

[0087] As described above, the honeycomb segments used to create the honeycomb structure of Example 1 were produced. In each honeycomb segment, a square section perpendicular to the axial direction was formed, and the length of one side of the square (the segment size) was 42 mm. The honeycomb segment had a length of 141.0 mm in the axial direction. The honeycomb segment had a septum thickness of 0.305 mm and a cell density of 46.5 cells / cm². 2 .

[0088] Then a binding material was prepared to join the honeycomb segments. An organic binder, a foamable resin, and a dispersion agent were added to an inorganic raw material to form a binding layer. Water was then added, the mixture was kneaded into a slurry, and used as a binding material.

[0089] The resulting honeycomb segments were then joined with the binding material, positioned so that their sides faced each other. On the end face of the joined honeycomb segment, the segments were arranged as four longitudinally and four transversely. A binding layer was then dried and hardened within the joined honeycomb segment and subsequently subjected to heat treatment. Finally, the honeycomb structure in Example 1 was formed into a round column shape by grinding the circumference of the joined honeycomb segment.

[0090] A peripheral coating material was then prepared using the following procedure. First, coarse silicon carbide particles with an average particle diameter of 20 µm, fine silicon carbide particles with an average particle diameter of 3 µm, aluminum oxide particles with an average particle diameter of 4 µm, and cordierite particles with an average particle diameter of 40 µm were produced as aggregate particles. The average particle diameter was measured using laser diffraction / laser scattering. Additionally, colloidal silicon dioxide was prepared as a binder. These were mixed such that coarse silicon carbide particles comprised 30 parts by mass, fine silicon carbide particles 10 parts by mass, aluminum oxide particles 20 parts by mass, cordierite particles 15 parts by mass, and colloidal silicon dioxide 25 parts by mass.The mixture formulas of the aggregate particles are shown in the columns “Coarse silicon carbide”, “Fine silicon carbide”, “Aluminum oxide” and “Cordierite” in Table 1.

[0091] Then, water and an organic binder were added to the mixed powder obtained by blending each raw material, and each raw material was mixed to produce a perimeter coating material. It should be noted that in the mixture, when the total mass of the mixed powder was set to 100 parts by mass, water was set to 25 parts by mass, and an organic binder was set to 0.1 parts by mass.

[0092] The viscosity of the resulting peripheral coating material was determined by measuring the shear stress (Pa) of the peripheral coating material. The shear stress (Pa) of the peripheral coating material was measured using a rotational viscometer at a rotational speed of 2.0 s⁻¹. -1Measurements were taken at a temperature of 25 °C. The results are shown in Table 1.

[0093] The circumferential coating material was then applied to the circumference of the previously produced honeycomb structure and dried to create circumferential coating layers. The thickness of the circumferential coating layer was approximately 0.2 mm. The resulting honeycomb structure was the honeycomb structure of Example 1. The honeycomb structure of Example 1 had an end-face diameter of 165.0 mm. In Example 1, 10 honeycomb structures were produced in the manner described above.

[0094] For the honeycomb structure of Example 1, the 20 mm portion from the second side of the end face of the peripheral coating layer was the print area. The brightness (L*) in the L*a*b* color space (CIE1976), defined by the International Commission on Illumination (CIE), was measured for the print areas of the peripheral coating layers using a spectrocolorimeter (“CM-2600d / 2500d (trade name)”, manufactured by Konica Minolta Japan, Inc.). The brightness (L*) was 35. The results are shown in the “L*” column in Table 2.

[0095] Furthermore, the surface roughness Ra (the arithmetic mean of the roughness) of the printed area of ​​the peripheral coating layer was calculated using the stylus-type surface roughness meter. Then, the mean surface roughness Ra of the printed area of ​​the peripheral coating layer of the 10 honeycomb structures was determined. This mean value was the surface roughness Ra of the printed area of ​​the peripheral coating layer of the honeycomb structure from Example 1. The surface roughness Ra of the printed area of ​​the peripheral coating layer was 10 µm. The results are shown in Table 2.

[0096] Then, a 20 mm section of the second side of the end face of the circumferential coating layer of the 10 honeycomb structures of Example 1 was defined as the print area, and a two-dimensional code was printed within this area. The print size was 16 mm. Printing was carried out as follows.

[0097] The circumferential surface of the honeycomb structure was irradiated with a laser to develop a color-developing component (e.g., silicon carbide) contained in the circumferential coating layer, thereby printing a two-dimensional code. Laser printing was performed using a CO2 laser marking system at a power of 20 W and a scanning speed of 500 mm / s.

[0098] A readability test was then performed on the printed two-dimensional code applied to the printed area using the following procedure. The printed two-dimensional codes in 10 honeycomb structures of Example 1 were read by a two-dimensional code reader. The two-dimensional code reader used was the "DataMan302x (trade name)," manufactured by COGNEX. The readability of each of the 10 honeycomb structures was then assessed using grades A to D and F according to the "readability class" in ISO / IEC 15415 standards. The results are shown in the "Readability Test" column in Table 2. Only the alphabetical letters A to D and F are shown in the "Readability Test" column. The "DataMan302x (trade name)" two-dimensional code reader obtains the grades A to D and F by assessing the readability of the two-dimensional code.In the case of rating A, readability is best, meaning that readability decreases sequentially from rating A to rating F. In this two-dimensional code reader, there is no rating E result, and rating F follows rating D. For example, in the "Read Test" column of Table 2, "DC" indicates that the rating results for the 10 honeycomb structures were either rating D or rating C. [Table 1] Mixture proportion of aggregate particles (in a total quantity of 75 parts by weight) Shear stress (Pa) of a circumferential coating material Coarse silicon carbide (parts by weight) Fine silicon carbide (parts by weight) Aluminum oxide (parts by weight) Cordierite (by weight) Titanium oxide (parts by weight) Comparative Example 1 40 0 20 15 0 180 Comparative Example 2 40 0 20 15 0 220 Comparative Example 3 40 0 20 15 0 250 Comparative Example 4 40 0 20 15 0 20 Comparative Example 5 40 0 20 15 0 255 Comparative Example 6 40 0 20 15 0 15 Example 1 30 10 20 15 0 180 Example 2 30 10 20 15 0 220 Example 3 30 10 20 15 0 250 Example 4 30 10 20 15 0 20 Comparative Example 7 30 10 20 15 0 255 Comparative Example 8 30 10 20 15 0 15 Example 5 10 30 20 15 0 180 Example 6 10 30 20 15 0 220 Example 7 10 30 20 15 0 250 Example 8 10 30 20 15 0 20 Comparative Example 9 10 30 20 15 0 255 Comparative Example 10 10 30 20 15 0 15 Example 9 10 30 25 10 0 180 Example 10 10 30 30 5 0 180 Example 11 10 30 35 0 0 180 Example 12 10 30 20 10 5 180 Example 13 10 30 20 5 10 180 Example 14 10 30 20 0 15 180 Example 15 0 40 25 0 10 180 Example 16 0 40 25 0 10 140 [Table 2] Test number L* Surface roughness Ra (µm) Reading comprehension Comparative Example 1 30 10 F Comparative Example 2 30 20 F Comparative Example 3 30 30 F Comparative Example 4 30 30 F Comparative Example 5 30 35 F Comparative Example 6 30 35 F Example 1 35 10 CD Example 2 35 20 CD Example 3 35 30 D Example 4 35 30 D Comparative Example 7 35 35 F Comparative Example 8 35 35 F Example 5 50 10 C Example 6 50 20 CD Example 7 50 30 CD Example 8 50 30 CD Comparative Example 9 50 35 F Comparative Example 10 50 35 F Example 9 55 10 BC Example 10 60 10 BC Example 11 60 10 B Example 12 65 10 B Example 13 70 10 AWAY Example 14 70 10 AWAY Example 15 75 10 AWAY Example 16 75 5 A (Examples 2 to 16 and comparative examples 1 to 10)

[0099] When preparing the peripheral coating material, the proportion of aggregate particles (in a total quantity of 75 parts by mass) was changed, as shown in Table 1, to produce the honeycomb structures of Examples 2 to 16 and Comparative Examples 1 to 10 in the same manner as in Example 1. Ten pieces of each honeycomb structure were also produced for Examples 2 to 16 and Comparative Examples 1 to 10. In Examples 12 to 16, titanium oxide particles were added as the aggregate particle to prepare the peripheral coating material. Specifically, 5 parts by mass of titanium oxide particles were used in Example 12. 10 parts by mass of titanium oxide particles were used in Examples 13, 15, and 16. 15 parts by mass of titanium oxide particles were used in Example 14.

[0100] In the examples and comparative examples, the shear stresses (Pa) of the peripheral coating material were modified during the preparation of the peripheral coating material, as shown in Table 1. The shear stress (Pa) of the peripheral coating material was adjusted by increasing or decreasing the amount of water and binder added to the peripheral coating material.

[0101] The brightness (L*) in the L*a*b* color space (CIE1976), defined by the International Commission on Illumination (CIE), was measured using a spectrocolorimeter for the printed area of ​​the peripheral coating layers of the honeycomb structures of Examples 2 to 16 and the comparative Examples 1 to 10. The results are shown in Table 2.

[0102] For the honeycomb structures of Examples 2 to 16 and the comparative Examples 1 to 10, the readability tests were performed in the same manner as in Example 1. The imprints applied to the printed areas of the circumferential coating layers of the honeycomb structures were two-dimensional codes similar to those of Example 1. Furthermore, a comprehensive decision was made based on the readability test. The results are shown in Table 2. (Results)

[0103] In the honeycomb structures of Examples 1 to 16, the brightness (L*) of the printed area of ​​the peripheral coating layer was 35 or higher, the surface roughness (Ra) was 30 µm or lower, and the readability of the imprint (two-dimensional code) applied to the printed area was good. Conversely, in the honeycomb structures of the comparative Examples 1 to 6, the brightness (L*) of the printed area of ​​the peripheral coating layer was 35 or lower, numerous reading errors were confirmed in the imprint applied to the printed area, and readability was poor. The results confirmed that even when the surface roughness (Ra) of the printed area was 30 µm or lower, as in the honeycomb structures of comparative Examples 1 to 4, readability was extremely poor when the brightness (L*) of the printed area was 35 or lower.Furthermore, in the honeycomb structures of comparative examples 7 to 10, even when the brightness (L*) of the print area was 35 or more, the surface roughness Ra of the print area was greater than 30 µm and the readability was poor.

[0104] A honeycomb structure of the present invention is suitable for use as a catalyst support for loading a catalyst or as a filter in various fields such as passenger cars, chemistry, electrical energy, iron and steel. Description of reference symbols

[0105] 1, 31: Partition wall, 2, 32: Cell, 3: Perimeter wall, 10, 40: Honeycomb structure body, 11, 41: First end face, 12, 42: Second end face, 20, 50: Perimeter coating layer, 21, 51: Pressure area, 34: Honeycomb segment, 35: Sealing section, 36: Bonding layer, 100, 200: Honeycomb structure

Claims

[1] Honeycomb structure comprising the following: a columnar honeycomb structure body that has a porous partition wall such that it surrounds several cells running from a first end face to a second end face, and a circumferential coating layer formed from a circumferential coating material that is coated on at least a part of the circumference of the honeycomb structure body, wherein the peripheral coating layer has a printing area for printing on its surface, the print area has a brightness (L*) of 35 or more in the L*a*b* color space (CIE1976), which is defined by the International Commission on Illumination (CIE), and The printing area has a surface roughness Ra of 30 µm or less. [2] Honeycomb structure according to claim 1, wherein the circumferential coating layer contains several aggregate particles and a neck material for connecting the aggregate particles together. [3] Honeycomb structure according to claim 1 or 2, wherein the cells in the honeycomb structure body are sealed by sealing sections at one end either on the side of the first end face or on the side of the second end face of the honeycomb structure body. [4] Honeycomb structure according to one of claims 1 to 3, wherein the circumferential coating layer is arranged such that it surrounds the perimeter of the honeycomb structure body. [5] Honeycomb structure according to any one of claims 1 to 4, wherein the circumferential coating layer contains a laser color development component which develops a color different from the original color by means of a laser. [6] Honeycomb structure according to any one of claims 1 to 5, wherein the circumferential coating layer is formed from a porous material. [7] Honeycomb structure according to any one of claims 1 to 6, wherein the content of at least one component of silicon carbide, metallic silicon, magnesium oxide and aluminium oxide in a part forming the printing area of ​​the circumferential coating layer is 20 wt% or more in relation to 100 wt% of the components of the part. [8] Honeycomb structure according to one of claims 1 to 7, wherein the printing area serves to print an information code. [9] Honeycomb structure according to claim 8, wherein the information code is a two-dimensional code. [10] Honeycomb structure according to claim 9, wherein a dot size of the two-dimensional codes is in the range of 0.3 mm to 1.0 mm. [11] Manufacturing method of a honeycomb structure according to any one of claims 1 to 10, comprising coating the circumferential coating material on at least a part of the circumference of the honeycomb structure body, wherein the peripheral coating material contains as aggregate particles at least one selected from the group consisting of fine silicon carbide particles, aluminum oxide particles, cordierite particles, titanium oxide particles and aluminum nitride particles, which have an average particle diameter in the range of 1 to 5 µm, wherein the circumferential coating material is manufactured in such a way that a shear load (Pa) measured by a rotational viscometer at a rotational speed of 2.0s -1 Measured at a temperature of 25 °C, the pressure is in the range of 20 to 250 Pa.

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