JPWO2007049349A1 - Application head - Google Patents

Abstract

A coating head in a coating apparatus that coats the surface of a member to be coated such as a sheet-like member is less likely to be damaged. Provided is a coating head in which members made of cemented carbide are arranged effectively at the tip of the coating head, and these members are incorporated so as not to create a gap through which the paint penetrates. The coating head may be characterized in that the tip portion thereof is coated with a cemented carbide having a predetermined thickness. The cemented carbide may be a cermet containing tungsten carbide (WC). Furthermore, this coating can be performed by thermal spraying.

Description

  The present invention relates to a coating tool and a coating apparatus for coating a coating liquid on the surface of a member to be coated such as a sheet-shaped member or a plate-shaped member, and more particularly to a coating tool and a coating apparatus provided with a slot-shaped coating nozzle.

  Conventionally, the surface of an object to be coated has been coated with various films typified by a heat-sensitive film, a conductive film, a low-reflection conductive film, an anti-ultraviolet film, an anti-electromagnetic wave film, a protective film, or a magnetic film. Yes. For example, a coating tool having a slot through which a coating liquid is passed as a coating tool to be applied to a coating apparatus that performs a coating operation to apply a coating liquid thinly and uniformly on the surface of a sheet-like member to form a coating film layer Is used. As such an application tool, there is an application tool provided with an application head (tool body). This is illustrated in FIG.

  The coating apparatus 911 includes a coating head 910, and the coating head 910 is configured by attaching a first member 911 called a back edge and a second member 912 called a doctor edge to each other. . The coating apparatus includes a feeding means (not shown) that causes the flexible belt-like support 914 to travel in the direction of the arrow (B) in the figure, and the first member 911 and the second member 912 are flexible belt-like. The support bodies 914 are arranged in order along the traveling direction (b). That is, the first member 911 is disposed on the upstream side in the direction (b) in which the flexible belt-like support 914 travels, and the second member 912 is disposed on the downstream side. Between the first and second members 911 and 912, a slot 913 is formed through which the coating liquid flows toward the tips of the first member 911 and the second member 912. At the tip of the slot 913, An outflow port 913 a that opens at the tip of the first and second members 911 and 912 is formed.

  The coating head 911 having a slot-shaped nozzle may be scratched at the tip of the coating blade due to contact with the member to be coated 914, corrosion due to paint, and friction with particles such as pigments that may be included. When the size of such scratches exceeds a predetermined value, the paint enters the scratches, making it difficult to form a uniform coating film. Therefore, when the scratches become large to some extent, it is necessary to regenerate the head tip portion by polishing the blade edge portion. Therefore, the productivity of the coating process is significantly reduced, such as periodic inspection and maintenance of the coating apparatus, suspension of the coating apparatus during head regeneration or preparation of a spare head, and precise mounting of the head after regeneration.

  FIG. 7 schematically shows examples of scratches 950 and 952 generated in the head 942. Due to contact with the member to be coated, etc., there are scratches 952 that gradually become narrower triangular from the running direction, and there are some that penetrate to the opposite side and have deep valleys 954. Typical scratch widths are as large as about 0.1 to 0.3 mm, and such scratches penetrate the paint and hinder stable film formation.

  For this reason, it is desired that the tip of the coating head is less likely to be scratched. Specifically, it has been proposed to use a cemented carbide material for the coating head (for example, Patent Document 1).

However, it is not practical to make the entire coating head a cemented carbide because of the cost and low machinability. For this reason, it has been proposed that only the tip portion of the coating head is made of cemented carbide (for example, Patent Document 2 and Patent Document 3), but it is not easy to assemble so that the width of the slot of the tip portion is uniform. Absent. In particular, even if the assembly is performed precisely at the initial stage of assembly, it is easy to change with time due to the stress caused by the difference in thermal expansion between the members as the coating operation is repeated. Furthermore, in assembly, a minute gap is likely to be generated between the members, and the coating material may permeate into the gap and change the application conditions.
JP 2000-301044 A JP 2002-224607 A JP 2004-261678 A

  In consideration of the above, the present invention provides a coating head in which the hardness of only the tip portion of the head is effectively increased. Thereby, wear of the tip portion is suppressed and a coating film can be formed stably.

  In the present invention, the coating head is configured such that members made of cemented carbide are arranged effectively at the tip portion, and these members are incorporated so as not to generate a gap through which the paint penetrates. That is, the tip portion may be coated with a cemented carbide having a predetermined thickness. The cemented carbide may be a cermet containing tungsten carbide (WC). Furthermore, this coating can be performed by thermal spraying. Therefore, the thermal spray material to be sprayed may be a cermet containing tungsten carbide (WC).

  More specifically, the following is provided.

(1) An application head for supplying paint to form a coating film on a sheet-like member, a slot-type application nozzle having a slot extending in a direction substantially perpendicular to the application direction to the sheet-like member; A coating head main body for holding the coating nozzle, the coating nozzle having two nozzle tip members facing each other with a predetermined width defining the slot, and at least the sheet-like member or plate of the nozzle tip member A coating head comprising a cemented carbide coating layer formed by thermal spraying on a portion facing the shaped member.

(2) The coating head according to (1), wherein a base material of the coating nozzle is made of stainless metal, and the cemented carbide coating layer is formed thereon.

(3) A cemented carbide processing method for a slotted coating nozzle of an application head that supplies paint to form a coating film on a sheet-like member or plate-like member, and after spraying the cemented carbide on the tip of the application head, A cemented carbide processing method characterized by polishing into a predetermined shape.

(4) A coating head, which is a slot type coating nozzle for forming a coating film on a plate-like workpiece and is formed by spraying a cemented carbide on the nozzle tip.

  (5) The coating head according to (4), wherein the coating head is made of stainless steel for the main body and cemented carbide for the tip.

  (6) A cemented carbide processing method of a slot type coating nozzle for forming a coating film on a plate-like workpiece, wherein a cemented carbide is sprayed on the tip of the coating head and then the shape is adjusted by polishing.

  Here, the thermal spraying may include explosive thermal spraying capable of forming a dense thermal sprayed film, thermal spraying with a high-temperature combustion gas, plasma spraying, and the like. Moreover, a sealing process can also be performed as needed.

A coating head having a tip coated with a cemented carbide is shown together with a member to be coated. It is a perspective view including a section of a coating head sprayed with a cemented carbide at the tip and shown together with a member to be coated. It is a schematic sectional drawing which shows the state before thermal spraying of the coating head front-end | tip part. It is a schematic sectional drawing which shows the state after the thermal spraying of the coating head front-end | tip part. It is a schematic sectional drawing which shows the state after grinding | polishing of the coating head front-end | tip part. It is a disassembled perspective view which shows the detailed structure of a coating head. It is sectional drawing which shows typically the outline of the gun part of the jet coat used in the Example of this invention. It is a side view which shows typically the outline of the gun used for the jet coat used in the Example of this invention. It is a figure which shows the data sheet which listed the general characteristic of the thermal spray coating used suitably for this invention. It is a figure which shows the data sheet which put together the characteristic of the thermal spray material (TS-10713) used suitably for this invention. It is a figure which shows the data sheet which put together the characteristic of the thermal spray material (TS-03084) used suitably for this invention. It is a figure which shows the data sheet which put together the characteristic of the thermal spray material (TS-1305) used suitably for this invention. It is a figure which shows the data sheet which put together the characteristic of the thermal spray material (TS-10718) used suitably for this invention. It is a figure which shows the data sheet which put together the characteristic of the thermal spray material (TS-1301) used suitably for this invention. It is a figure which shows the data sheet which put together the characteristic of the thermal spray material (TS-3092N) used suitably for this invention. It is a figure which shows the data sheet which put together the characteristic of the thermal spray material (TS-12006) used suitably for this invention. It is a figure which shows the data sheet which put together the characteristic of the thermal spray material (TS-11811) used suitably for this invention. It is a figure which shows the data sheet which put together the characteristic of the thermal spray material (TS-20142NB) used suitably for this invention. It is a perspective view which shows the conventional coating head. It is a perspective view which shows typically the damage | wound made in an application head.

Explanation of symbols

20 coating head 21, 22 split head 21a, 22a tip 23 shim 26 cavity 27 slot 42 spray coating

  FIG. 1 shows a cross-sectional view of a coating head including a tip member sprayed with cemented carbide together with a member to be coated schematically. FIGS. 2A to 2C show step by step how cemented carbide is processed on the tip member of the coating head. FIG. 3 is an exploded perspective view showing a detailed structure of the coating head.

  A coating head that performs coating on the liquid crystal substrate 4 will be described as a preferred example with reference to FIGS. 1A and 1B, a sheet-like liquid crystal substrate 4 extending in the left-right direction is disposed at the lower portion, and a coating head 20 is disposed thereon. The liquid crystal substrate or the coating head 20 is relatively moved from right to left (or from left to right) in the drawing, and a coating film is formed from left to right (or from right to left). In FIG. 1A, for the sake of explanation, the coating head 20 is depicted with a large distance from the top of the liquid crystal substrate 4 to the top surface of the liquid crystal substrate 4, but in reality, the liquid crystal substrate 4 is coated with a shorter distance D (for example, 50 to 150 μm). (FIG. 1B). Therefore, direct or indirect contact between the upper surface of the liquid crystal substrate 4 and the tip of the coating head 20 may occur, and the tip or tip of the coating head 20 may be worn or scratched.

  The coating head 20 is composed of divided heads 21 and 22 that face each other at a predetermined interval. Each of the two divided heads 21 and 22 is made of a long and thin rectangular parallelepiped metal (stainless steel) block. The predetermined interval between the divided blocks 21 and 22 can be defined by sandwiching the shim 23. The divided blocks 21 and 22 have substantially parallel opposing surfaces, and these surfaces extend substantially vertically downward, and extend substantially horizontally in the width direction of the respective divided blocks 21 and 22. The coating head 20 is provided so as to maintain the respective surfaces facing the above-mentioned cutting edge portions that project downward at an acute angle. In other words, in the coating head 20, the thickness of the divided blocks 21 and 22 is gradually reduced so that the tip edge of the blade edge becomes the tip edge below the facing surface.

  The front end portions 21a and 22a of the divided blocks 21 and 22 which are the lower end nozzle portions of the coating head 20 have the width of the liquid crystal substrate 4 (the length of the liquid crystal substrate 4 in the direction perpendicular to the traveling direction of the coating head). It is formed almost horizontally so as to have a length exceeding it, and becomes a nozzle portion. The tip portions 21a and 22a are opposed to each other at a predetermined interval as described above. By flowing a predetermined amount of paint per unit time (for example, about 2 cc / sec for a general liquid crystal substrate) from a slot 27 having a predetermined interval defined by the tip portions 21a and 22a, a uniform coating film is obtained. Form.

  The predetermined interval of the slot 27 can be defined by a shim 23 sandwiched between the divided blocks 21 and 22. As shown in FIG. 3, the shim 23 is formed of a thin plate punched into a U-shape of katakana in a plan view, and the side portions 23 a and 23 b of the U-shaped recess are formed by two divided heads 21, When the shim 23 is sandwiched between the two divided heads 22, a predetermined gap is maintained between the two divided heads 21 and 22. A slot 27 is formed by this gap. The thickness of the shim 23 determines the size of the gap in the slot 27. That is, when the split heads 21 and 22 are fastened by bolts 60 and nuts 61 as fastening members passing through the bolt holes 51 and 52 and the bolt holes 53 of the shim 23, the thickness of the shim 23 is substantially equal to that of the slot 27. It becomes the gap interval.

  A liquid injection port 24 for injecting a liquid or the like that forms a coating liquid (or paint) is formed in the upper part of one of the divided heads 21 at a substantially central position in the width direction (width direction of the coating head 20). Air vents 34 are formed near both ends in the length direction. The liquid inlet 24 and the air vent 34 communicate with the cavity 26 provided in the middle or inside of the divided head 21 through the through holes 25, respectively. The cavity 26 extends in the width direction of the divided head 21, and the liquid or the like injected from the liquid injection port 24 flows in the width direction from approximately the center to both ends. At this time, the air remaining in the cavity is discharged from the air vent 34 through the through hole 25. Thus, the cavity part 26 can hold the liquid or the like thus injected in the cavity part.

  The cavity 26 communicates with the slot 27, and the liquid in the cavity 26 is made to have a constant thickness by the slot 27 and is discharged from the tip opening 28 below the slot 27. The front end opening 28 of the slot 27 forms a nozzle opening of the lower end nozzle portion of the coating head 20.

  The tip portions 21a and 22a of the opposing surfaces of the divided heads 21 and 22 are respectively coated with a coating 42 by thermal spraying so that the surface roughness is fine and the distortion in the width direction is small. . For example, the surface roughness of the thermal spray coatings 42a and 42b attached to the tip portions 21a and 22a is, for example, 0.1 to 0.2 [mu] m, more preferably 0.025 to 0.05 [mu] m in terms of Ra as measured by JIS. It is. The distance between the slots 27 is such that the shim thickness is ± 0.1 μm, the head mating surface is within 2 μm, and the maximum is 2.1 μm or less. Therefore, if the surface roughness and the interval are out of this range, it is not preferable because it is difficult to form a uniform coating film. When scratches enter, unevenness in the width direction of the discharged paint tends to occur, and streaks are likely to enter the coating film. Accordingly, it is difficult to form a uniform coating film. Such scratches are caused by contact with or sliding on the surface irregularities of the liquid crystal substrate 4 that is the object to be coated, foreign matter such as contamination on the surface, and solid matter in the paint in the process of applying the paint. obtain. In this embodiment, the hard coating tip is further coated by spraying on the cutting head portion made of stainless steel, the hardness is high, and such scratches are unlikely to occur.

  2A to 2C, the thermal spraying procedure on the divided head 21 will be described. First, the equipment shape of the division block of the coating head is formed by machining or the like. At this time, it is more preferable that the portions to be sprayed on the coating head blade edge are provided with depressions 44 and 46 in advance so as to be thin (FIG. 2A). This is because it becomes difficult to make a step on the outer side 42C or the inner side 42b of the tip.

  When cemented carbide is sprayed on the depressions 44, 46, etc., the cutting edge portion can have a slightly rounded shape 48 as shown in FIG. 2B. The reason why the thermal spraying is slightly thick is that if it is thin, there is a possibility that scratches that cannot be removed in the subsequent polishing process may be formed. At this time, sealing can be optionally performed. Open holes can be the starting point of scratches and are generally considered effective to prevent unnecessary paint penetration.

  Next, the tip portion is polished and finished to the required shape (FIG. 2C). Further, it is possible to carry out a sealing treatment and perform a precise polishing of the surface again, but this is not an essential requirement. The final thickness of the sprayed coating was about 0.4 mm. This thickness is preferably 0.2 mm or more, and more preferably 0.3 mm or more. Moreover, this thickness is preferably 1 mm or less, and more preferably 0.8 mm or less. This is because if the thickness is too thin, the abrasion resistance is not sufficient, and if it is too thick, the film may be peeled off, and the optimum film thickness to be applied by thermal spraying will be greatly exceeded. The divided heads 22 are also manufactured in the same procedure, and these are fastened with a bolt or the like through the shim 23 to form an application head.

  By manufacturing in this way, the coating head does not enter into the joint portion of different materials, and a coating head which is difficult to be damaged is completed.

  FIG. 4A shows, in cross-section, a gun portion 100 used in an HVOF (High Velocity Oxy-Fuel) spraying method that can be suitably used in an embodiment of the present invention. From a Laval nozzle, a gas containing a high-speed thermal spray material that is 5 times the speed of sound is sprayed toward the right substrate 112 to form a coating film 114. Several diamond-shaped objects 110 are arranged in the high-speed gas, and are called shock diamonds 110. Such a high-speed gas is obtained by sending oxygen and combustion gas (for example, propylene) to the gun portion 100 as indicated by an arrow 106 and generating high-speed flame by the high-pressure oxygen and propylene combustion gas. It is done. Thermal spray material (powder) is supplied as indicated by the center arrow 104, and is heated and melted at the center of the frame. The combustion temperature may be 2700 ° C., for example, and the flame speed reaches 1500 m / sec. Compressed air is sent as indicated by an arrow 108 to protect the nozzle 102 and the like from this high temperature. As described above, since the speed of sound is exceeded, shock diamond 110 is seen, and a flat sprayed coating can be formed on the substrate by its kinetic energy. Therefore, it has a feature that it has a super-dense and finely sprayed skin, a high bonding strength is obtained because of high density strength, and a phase change of the base material is small because of low residual stress.

  Such thermal spray systems include JET KOTE (jet coat) thermal spray systems. This jet coat was purchased from the Browsing Engineering Co. in the early 1980s. (United States), Union Carbide Co. This is a new high-energy gas spraying method developed against d-gun of (US). In particular, the supersonic jet combustion gas flow around Mach 5 enables extremely high-sheath and high-density powder spraying. Furthermore, it is particularly suitable for spraying carbide-based cermets and superalloy materials. For materials in this field, it is possible to form a film with higher density and higher adhesion than conventional plasma spraying methods.

  FIG. 4B shows an outline of the gun of the jet coat in a side view. From the tip of the gun barrel 101 extending to the right from the gun body 103, the powder spray material is conveyed to the high-speed combustion gas flow 111, and a coating 114 is formed on the substrate 112. This high-speed combustion gas flow is generated when the combustion gas and oxygen supplied from the combustion gas supply port and the oxygen supply port are burned in the combustion chamber 105. As described above, since the high density and high adhesion force due to the high-speed gas flow are characteristic, the angle between the surface of the substrate 112 and the gas flow is important, and it is desirable that the angle be as perpendicular as possible. Therefore, as in this embodiment, in order to form sprayed coatings on three orthogonal surfaces, it is desirable that the above-described gun spraying is performed from a direction suitable for each surface. Specifically, it is preferable that the workpiece or the gun is fixed at an appropriate position, and if necessary, one of them is slid in a direction parallel to the substrate surface.

  FIG. 5A shows a data sheet that summarizes the materials for thermal spraying preferably used in the present invention. Some of these materials are suitably used. Broadly divided into two categories: carbide cermet and metal / alloy. It can be seen that the carbide cermet has a relatively low hardness but a relatively high hardness and is more suitable for use in the examples of the present invention. That is, as shown in FIG. 7, since the wear is so-called abrasive wear such as scratches, it is considered that the high hardness contributes greatly. Furthermore, the porosity is relatively low at 0.5% or less, and the penetration of the paint hardly occurs. In addition, if the paint is corrosive, it is preferable to use one having excellent corrosion resistance.

  Data sheets summarizing more detailed characteristics of each component are shown in FIGS. 5B to 5J. Of these, materials other than these, preferred materials, or combinations thereof are used to perform thermal spraying as described above and perform carbide machining of the tip of the head to greatly reduce wear. It is possible to achieve a great effect on uniform formation of a coating film.

  The present invention relates to a coating tool and a coating apparatus for coating a coating liquid on the surface of a member to be coated such as a sheet-shaped member or a plate-shaped member, and more particularly to a coating tool and a coating apparatus provided with a slot-shaped coating nozzle.

Conventionally, various surfaces typified by heat-sensitive films, conductive films, low-reflective conductive films, UV-preventing films, electromagnetic wave-preventing films, protective films, or magnetic films have been applied to the surface of objects to be coated . . For example, a coating tool having a slot through which a coating liquid is passed as a coating tool to be applied to a coating apparatus that performs a coating operation to apply a coating liquid thinly and uniformly on the surface of a sheet-like member to form a coating film layer Is used. As such an application tool, there is an application tool provided with an application head (tool body). This is illustrated in FIG.

The coating apparatus includes a coating head 910, and the coating head 910 is configured by attaching a first member 911 called a back edge and a second member 912 called a doctor edge to each other. The coating apparatus includes a feeding means (not shown) that causes the flexible belt-like support 914 to travel in the direction of the arrow (B) in the figure, and the first member 911 and the second member 912 are flexible belt-like. The support bodies 914 are arranged in order along the traveling direction (b). That is, the first member 911 is disposed on the upstream side in the direction (b) in which the flexible belt-like support 914 travels, and the second member 912 is disposed on the downstream side. A slot 913 is formed between the first and second members 911 and 912 to allow the coating liquid to flow toward the tips of the first member 911 and the second member 912. At the tip of the slot 913, Outflow ports 913 a that open at the tips of the first and second members 911 and 912 are formed.

The coating head 910 having a slot-like nozzle may be scratched at the tip of the coating blade due to contact with the member to be coated 914, corrosion due to paint, and friction with particles such as pigments that may be included. When the size of such scratches exceeds a predetermined value, the paint enters the scratches, making it difficult to form a uniform coating film. Therefore, when the scratches become large to some extent, it is necessary to regenerate the head tip portion by polishing the blade edge portion. Therefore, the productivity of the coating process is significantly reduced, such as periodic inspection and maintenance of the coating apparatus, suspension of the coating apparatus during head regeneration or preparation of a spare head, and precise mounting of the head after regeneration.

FIG. 7 schematically shows examples of scratches 950 and 952 generated in the head 942. There are scratches 952 that gradually become narrower triangular from the traveling direction due to contact with the member to be coated, and some of them have penetrated to the opposite side and deep valleys 954 are generated. Typical scratch widths are as large as about 0.1 to 0.3 mm, and such scratches penetrate the paint and hinder stable film formation.

  For this reason, it is desired that the tip of the coating head is less likely to be scratched. Specifically, it has been proposed to use a cemented carbide material for the coating head (for example, Patent Document 1).

However, it is not practical to make the entire coating head a cemented carbide because of the cost and low machinability. For this reason, it has been proposed that only the tip portion of the coating head is made of cemented carbide (for example, Patent Document 2 and Patent Document 3), but it is not easy to assemble so that the width of the slot of the tip portion is uniform. Absent. In particular, even if the assembly is performed precisely at the initial stage of assembly, it is easy to change with time due to the stress caused by the difference in thermal expansion between the members as the coating operation is repeated. Furthermore, in assembly, a minute gap is likely to be generated between the members, and the coating material may permeate into the gap and change the application conditions.
JP 2000-301044 A JP 2002-224607 A JP 2004-261678 A

In consideration of the above, the present invention provides a coating head in which the hardness of only the tip portion of the head is effectively increased. Thereby, wear of the tip portion is suppressed and a coating film can be formed stably.

  In the present invention, the coating head is configured such that members made of cemented carbide are arranged effectively at the tip portion, and these members are incorporated so as not to generate a gap through which the paint penetrates. That is, the tip portion may be coated with a cemented carbide having a predetermined thickness. The cemented carbide may be a cermet containing tungsten carbide (WC). Furthermore, this coating can be performed by thermal spraying. Therefore, the thermal spray material to be sprayed may be a cermet containing tungsten carbide (WC).

  More specifically, the following is provided.

(1) An application head for supplying paint to form a coating film on a sheet-like member, a slot-type application nozzle having a slot extending in a direction substantially perpendicular to the application direction to the sheet-like member; A coating head main body for holding the coating nozzle, the coating nozzle having two nozzle tip members facing each other with a predetermined width defining the slot, and at least the sheet-like member or plate of the nozzle tip member A coating head comprising a cemented carbide coating layer formed by thermal spraying on a portion facing the shaped member.

(2) The coating head according to (1), wherein a base material of the coating nozzle is made of stainless metal, and the cemented carbide coating layer is formed thereon.

(3) A cemented carbide processing method for a slotted coating nozzle of an application head that supplies paint to form a coating film on a sheet-like member or plate-like member, and after spraying the cemented carbide on the tip of the application head, A cemented carbide processing method characterized by polishing into a predetermined shape.

(4) A coating head, which is a slot type coating nozzle for forming a coating film on a plate-like workpiece and is formed by spraying a cemented carbide on the nozzle tip.

(5) The coating head according to (4), wherein the coating head is made of stainless steel for the main body and cemented carbide for the tip.

(6) A cemented carbide processing method of a slot type coating nozzle for forming a coating film on a plate-like workpiece, wherein a cemented carbide is sprayed on the tip of the coating head and then the shape is adjusted by polishing.

  Here, the thermal spraying may include explosive thermal spraying capable of forming a dense thermal sprayed film, thermal spraying with a high-temperature combustion gas, plasma spraying, and the like. Moreover, a sealing process can also be performed as needed.

1A and 1B show a cross-sectional view of a coating head including a tip member sprayed with a cemented carbide together with a coated member schematically shown. FIGS. 2A to 2C show step by step how cemented carbide is processed on the tip member of the coating head. FIG. 3 is an exploded perspective view showing a detailed structure of the coating head.

A coating head that performs coating on the liquid crystal substrate 4 will be described as a preferred example with reference to FIGS. 1A and 1B, a sheet-like liquid crystal substrate 4 extending in the left-right direction is disposed at the lower portion, and a coating head 20 is disposed thereon. A liquid crystal substrate or the coating head 20 is relatively moved from the right in the figure to the left (or left to right), the coating film is gradually formed from left to right (or from right to left). In FIG. 1A, for the sake of explanation, the coating head 20 is depicted with a large distance from the top of the liquid crystal substrate 4 to the top surface of the liquid crystal substrate 4, but in reality, the liquid crystal substrate 4 is coated with a shorter distance D (for example, 50 to 150 μm). (FIG. 1B). Therefore, direct or indirect contact between the upper surface of the liquid crystal substrate 4 and the tip of the coating head 20 may occur, and the tip or tip of the coating head 20 may be worn or scratched.

  The coating head 20 is composed of divided heads 21 and 22 that face each other at a predetermined interval. Each of the two divided heads 21 and 22 is made of a long and thin rectangular parallelepiped metal (stainless steel) block. The predetermined interval between the divided blocks 21 and 22 can be defined by sandwiching the shim 23. The divided blocks 21 and 22 have substantially parallel opposing surfaces, and these surfaces extend substantially vertically downward, and extend substantially horizontally in the width direction of the respective divided blocks 21 and 22. The coating head 20 is provided so as to maintain the respective surfaces facing the above-mentioned cutting edge portions that project downward at an acute angle. In other words, in the coating head 20, the thickness of the divided blocks 21 and 22 is gradually reduced so that the tip edge of the blade edge becomes the tip edge below the facing surface.

  The front end portions 21a and 22a of the divided blocks 21 and 22 which are the lower end nozzle portions of the coating head 20 have the width of the liquid crystal substrate 4 (the length of the liquid crystal substrate 4 in the direction perpendicular to the traveling direction of the coating head). It is formed almost horizontally so as to have a length exceeding it, and becomes a nozzle portion. The tip portions 21a and 22a are opposed to each other at a predetermined interval as described above. By flowing a predetermined amount of paint per unit time (for example, about 2 cc / sec for a general liquid crystal substrate) from a slot 27 having a predetermined interval defined by the tip portions 21a and 22a, a uniform coating film is obtained. Form.

  The predetermined interval of the slot 27 can be defined by a shim 23 sandwiched between the divided blocks 21 and 22. As shown in FIG. 3, the shim 23 is formed of a thin plate punched into a U-shape of katakana in a plan view, and the side portions 23 a and 23 b of the U-shaped recess are formed by two divided heads 21, When the shim 23 is sandwiched between the two divided heads 22, a predetermined gap is maintained between the two divided heads 21 and 22. A slot 27 is formed by this gap. The thickness of the shim 23 determines the size of the gap in the slot 27. That is, when the split heads 21 and 22 are fastened by bolts 60 and nuts 61 as fastening members passing through the bolt holes 51 and 52 and the bolt holes 53 of the shim 23, the thickness of the shim 23 is substantially equal to that of the slot 27. It becomes the gap interval.

A liquid injection port 24 for injecting a liquid or the like that forms a coating liquid (or paint) is formed in the upper part of one of the divided heads 21 at a substantially central position in the width direction (width direction of the coating head 20). at both ends near the longitudinal direction, the air vent port 34 is formed, respectively. The liquid inlet 24 and the air vent 34 communicate with the cavity 26 provided in the middle or inside of the divided head 21 through the through holes 25, respectively. The cavity 26 extends in the width direction of the divided head 21, and the liquid or the like injected from the liquid injection port 24 flows in the width direction from approximately the center to both ends. At this time, the air remaining in the cavity is discharged from the air vent 34 through the through hole 25. Thus, the cavity part 26 can hold the liquid or the like thus injected in the cavity part.

  The cavity 26 communicates with the slot 27, and the liquid in the cavity 26 is made to have a constant thickness by the slot 27 and is discharged from the tip opening 28 below the slot 27. The front end opening 28 of the slot 27 forms a nozzle opening of the lower end nozzle portion of the coating head 20.

  The tip portions 21a and 22a of the opposing surfaces of the divided heads 21 and 22 are respectively coated with a coating 42 by thermal spraying so that the surface roughness is fine and the distortion in the width direction is small. . For example, the surface roughness of the thermal spray coatings 42a and 42b attached to the tip portions 21a and 22a is, for example, 0.1 to 0.2 [mu] m, more preferably 0.025 to 0.05 [mu] m in terms of Ra as measured by JIS. It is. The interval between the slots 27 is ± 0.1 μm for the shim and within 2 μm for the mating surface of the head, and is 2.1 μm or less at the maximum. Therefore, if the surface roughness and the interval are out of this range, it is not preferable because it is difficult to form a uniform coating film. When scratches enter, unevenness in the width direction of the discharged paint tends to occur, and streaks are likely to enter the coating film. Accordingly, it is difficult to form a uniform coating film. Such scratches are caused by contact with or sliding on the surface irregularities of the liquid crystal substrate 4 that is the object to be coated, foreign matter such as contamination on the surface, and solid matter in the paint in the process of applying the paint. obtain. In this embodiment, the hard coating tip is further coated by spraying on the cutting head portion made of stainless steel, the hardness is high, and such scratches are unlikely to occur.

  2A to 2C, the thermal spraying procedure on the divided head 21 will be described. First, the equipment shape of the division block of the coating head is formed by machining or the like. At this time, it is more preferable that the portions to be sprayed on the coating head blade edge are provided with depressions 44 and 46 in advance so as to be thin (FIG. 2A). This is because it becomes difficult to make a step on the outer side 42C or the inner side 42b of the tip.

  When cemented carbide is sprayed on the depressions 44, 46, etc., the cutting edge portion can have a slightly rounded shape 48 as shown in FIG. 2B. The reason why the thermal spraying is slightly thick is that if it is thin, there is a possibility that scratches that cannot be removed in the subsequent polishing process may be formed. At this time, sealing can be optionally performed. Open holes can be the starting point of scratches and are generally considered effective to prevent unnecessary paint penetration.

  Next, the tip portion is polished and finished to the required shape (FIG. 2C). Further, it is possible to carry out a sealing treatment and perform a precise polishing of the surface again, but this is not an essential requirement. The final thickness of the sprayed coating was about 0.4 mm. This thickness is preferably 0.2 mm or more, and more preferably 0.3 mm or more. Moreover, this thickness is preferably 1 mm or less, and more preferably 0.8 mm or less. This is because if the thickness is too thin, the abrasion resistance is not sufficient, and if it is too thick, the film may be peeled off, and the optimum film thickness to be applied by thermal spraying will be greatly exceeded. The divided heads 22 are also manufactured in the same procedure, and these are fastened with a bolt or the like through the shim 23 to form an application head.

  By manufacturing in this way, the coating head does not enter into the joint portion of different materials, and a coating head which is difficult to be damaged is completed.

  FIG. 4A shows, in cross-section, a gun portion 100 used in an HVOF (High Velocity Oxy-Fuel) spraying method that can be suitably used in an embodiment of the present invention. From a Laval nozzle, a gas containing a high-speed thermal spray material that is 5 times the speed of sound is sprayed toward the right substrate 112 to form a coating film 114. Several diamond-shaped objects 110 are arranged in the high-speed gas, and are called shock diamonds 110. Such a high-speed gas is obtained by sending oxygen and combustion gas (for example, propylene) to the gun portion 100 as indicated by an arrow 106 and generating high-speed flame by the high-pressure oxygen and propylene combustion gas. It is done. Thermal spray material (powder) is supplied as indicated by the center arrow 104, and is heated and melted at the center of the frame. The combustion temperature may be 2700 ° C., for example, and the flame speed reaches 1500 m / sec. Compressed air is sent as indicated by an arrow 108 to protect the nozzle 102 and the like from this high temperature. As described above, since the speed of sound is exceeded, shock diamond 110 is seen, and a flat sprayed coating can be formed on the substrate by its kinetic energy. Therefore, it has a feature that it has a super-dense and finely sprayed skin, a high bonding strength is obtained because of high density strength, and a phase change of the base material is small because of low residual stress.

Such thermal spray systems include JET KOTE (jet coat) thermal spray systems. This jet coat was purchased from the Browsing Engineering Co. in the early 1980s. (United States), Union Carbide Co. This is a new high-energy gas spraying method developed against d-gun of (US). In particular, the supersonic jet combustion gas flow around Mach 5 enables extremely sharp and high-density powder spraying. Furthermore, it is particularly suitable for spraying carbide-based cermets and superalloy materials. For materials in this field, it is possible to form a film with higher density and higher adhesion than conventional plasma spraying methods.

  FIG. 4B shows an outline of the gun of the jet coat in a side view. From the tip of the gun barrel 101 extending to the right from the gun body 103, the powder spray material is conveyed to the high-speed combustion gas flow 111, and a coating 114 is formed on the substrate 112. This high-speed combustion gas flow is generated when the combustion gas and oxygen supplied from the combustion gas supply port and the oxygen supply port are burned in the combustion chamber 105. As described above, since the high density and high adhesion force due to the high-speed gas flow are characteristic, the angle between the surface of the substrate 112 and the gas flow is important, and it is desirable that the angle be as perpendicular as possible. Therefore, as in this embodiment, in order to form sprayed coatings on three orthogonal surfaces, it is desirable that the above-described gun spraying is performed from a direction suitable for each surface. Specifically, it is preferable that the workpiece or the gun is fixed at an appropriate position, and if necessary, one of them is slid in a direction parallel to the substrate surface.

  FIG. 5A shows a data sheet that summarizes the materials for thermal spraying preferably used in the present invention. Some of these materials are suitably used. Broadly divided into two categories: carbide cermet and metal / alloy. It can be seen that the carbide cermet has a relatively low hardness but a relatively high hardness and is more suitable for use in the examples of the present invention. That is, as shown in FIG. 7, since the wear is so-called abrasive wear such as scratches, it is considered that the high hardness contributes greatly. Furthermore, the porosity is relatively low at 0.5% or less, and the penetration of the paint hardly occurs. In addition, if the paint is corrosive, it is preferable to use one having excellent corrosion resistance.

  Data sheets summarizing more detailed characteristics of each component are shown in FIGS. 5B to 5J. Of these, materials other than these, preferred materials, or combinations thereof are used to perform thermal spraying as described above and perform carbide machining of the tip of the head to greatly reduce wear. It is possible to achieve a great effect on uniform formation of a coating film.

A coating head having a tip coated with a cemented carbide is shown together with a member to be coated. It is a perspective view including a section of a coating head sprayed with a cemented carbide at the tip and shown together with a member to be coated. It is a schematic sectional drawing which shows the state before thermal spraying of the coating head front-end | tip part. It is a schematic sectional drawing which shows the state after the thermal spraying of the coating head front-end | tip part. It is a schematic sectional drawing which shows the state after grinding | polishing of the coating head front-end | tip part. It is a disassembled perspective view which shows the detailed structure of a coating head. It is sectional drawing which shows typically the outline of the gun part of the jet coat used in the Example of this invention. It is a side view which shows typically the outline of the gun used for the jet coat used in the Example of this invention. It is a figure which shows the data sheet which listed the general characteristic of the thermal spray coating used suitably for this invention. It is a figure which shows the data sheet which put together the characteristic of the thermal spray material (TS-10713) used suitably for this invention. It is a figure which shows the data sheet which put together the characteristic of the thermal spray material (TS-03084) used suitably for this invention. It is a figure which shows the data sheet which put together the characteristic of the thermal spray material (TS-1305) used suitably for this invention. It is a figure which shows the data sheet which put together the characteristic of the thermal spray material (TS-10718) used suitably for this invention. It is a figure which shows the data sheet which put together the characteristic of the thermal spray material (TS-1301) used suitably for this invention. It is a figure which shows the data sheet which put together the characteristic of the thermal spray material (TS-3092N) used suitably for this invention. It is a figure which shows the data sheet which put together the characteristic of the thermal spray material (TS-12006) used suitably for this invention. It is a figure which shows the data sheet which put together the characteristic of the thermal spray material (TS-11811) used suitably for this invention. It is a figure which shows the data sheet which put together the characteristic of the thermal spray material (TS-20142NB) used suitably for this invention. It is a perspective view which shows the conventional coating head. It is a perspective view which shows typically the damage | wound made in an application head.

Explanation of symbols

20 coating head 21, 22 split head 21a, 22a tip 23 shim 26 cavity 27 slot 42 spray coating

Claims (3)

An application head that supplies paint to form a coating film on a sheet-like member,
A slot-type application nozzle having a slot extending in a direction substantially perpendicular to the application direction to the sheet-like member, and an application head main body holding the application nozzle,
The application nozzle has two nozzle tip members that oppose each other with a predetermined width defining the slot;
An application head comprising: a cemented carbide coating layer formed by thermal spraying on at least a portion of the nozzle tip member facing the sheet-like member or plate-like member.   2. The coating head according to claim 1, wherein a substrate of the coating nozzle is made of stainless metal, and the cemented carbide coating layer is formed thereon.   A cemented carbide processing method for a slot-type coating nozzle of a coating head that supplies paint to form a coating film on a sheet-shaped member or a plate-shaped member, wherein the cemented carbide is sprayed on the tip of the coating head and then polished and polished. Carbide processing method characterized by having a shape of

Images