阅读说明：本技术 气体喷出喷嘴及炉、以及加工膜的制造方法 (Gas ejection nozzle, furnace, and method for producing processed film ) 是由 千枝繁树 西川彻 野村文保 于 2019-02-22 设计创作，主要内容包括：获得从气体喷出面喷出的气体的流速沿着喷嘴长度方向均匀的气体喷出喷嘴。本发明的气体喷出喷嘴具有以与树脂膜相对的侧面作为气体喷出面的壳体、沿着喷嘴长度方向供给气体的气体供给口、和从气体供给口连通至气体喷出面的1个以上的均压室,至少1个均压室的气体喷出面一侧的面由隔板构成,并且在隔板上表面沿着喷嘴长度方向配置有两端具有开口的多个筒状体,所述多个筒状体被配置成各筒状体的轴方向与喷嘴长度方向正交,筒状体的从隔板立起的接近气体供给口一侧的壁面与隔板所形成的角θ为规定范围内,在筒状体的与隔板接触的面上以还贯通隔板的孔的形态设有气体流通孔。(A gas jetting nozzle is obtained in which the flow velocity of gas jetted from a gas jetting surface is uniform along the longitudinal direction of the nozzle. The gas ejection nozzle of the present invention includes a housing having a side surface facing a resin film as a gas ejection surface, a gas supply port for supplying a gas along a nozzle longitudinal direction, and 1 or more pressure equalizing chambers communicating from the gas supply port to the gas ejection surface, wherein a surface of at least 1 pressure equalizing chamber on the gas ejection surface side is formed of a partition plate, and a plurality of cylindrical bodies having openings at both ends are arranged on a partition plate upper surface along the nozzle longitudinal direction, the plurality of cylindrical bodies are arranged such that an axial direction of each cylindrical body is orthogonal to the nozzle longitudinal direction, an angle θ formed by a wall surface of each cylindrical body rising from the partition plate on the side close to the gas supply port and the partition plate is within a predetermined range, and gas flow holes are provided in the form of holes further penetrating through the partition plate on a surface of the cylindrical body contacting the partition plate.)

1. A gas ejection nozzle for blowing a gas onto the surface of the resin film,

the gas ejection nozzle includes:

a housing provided so that a longitudinal direction of the gas ejection nozzle extends in a width direction of the resin film, and having a gas ejection surface that ejects a gas on a side surface opposite to the resin film;

a gas supply port provided at one end of the housing and supplying gas in a nozzle length direction; and

1 or more pressure equalizing chambers communicating from the gas supply port to the gas ejection face,

a surface on the gas discharge surface side of at least 1 pressure equalizing chamber of the 1 or more pressure equalizing chambers is formed by a partition plate, and a plurality of cylindrical bodies having openings at both ends are arranged on the partition plate along the nozzle longitudinal direction, the plurality of cylindrical bodies being arranged such that the axial direction of each cylindrical body is orthogonal to the nozzle longitudinal direction,

an angle θ formed between a wall surface of the cylindrical body on a side close to the gas supply port among wall surfaces rising from the separator and the separator is an inner angle of a cross-sectional shape of the cylindrical body and is in a range of 55 ° to 120 °,

and a gas circulation hole which is also communicated with the partition plate is arranged on the surface of the cylindrical body, which is in contact with the partition plate.

2. The gas ejection nozzle according to claim 1, wherein the angle θ is in a range of 75 ° or more and 95 ° or less.

3. The gas ejection nozzle according to claim 1 or 2, wherein the pressure equalizing chamber in which the cylindrical body is arranged is a pressure equalizing chamber adjacent to the gas supply port.

4. According to claimThe gas discharge nozzle according to any one of claims 1 to 3, wherein an opening area of the gas flow hole is S in each of the tubular bodies₁And the area of the surface of the cylindrical body which is in contact with the partition plate except the surface of the cylindrical body which is erected from the partition plate and is in contact with the partition plate is S₂While, the aperture ratio S₁/S₂Is 0.85 or less.

5. The gas ejection nozzle according to any one of claims 1 to 4, wherein the gas flow hole is a slit extending in a longitudinal direction of the nozzle.

6. The gas ejection nozzle according to any one of claims 1 to 5, wherein a surface formed by each of the openings of the tubular body is a surface that is parallel to the nozzle longitudinal direction and substantially perpendicular to the partition plate.

7. The gas ejection nozzle according to any one of claims 1 to 6, wherein L2/L1 is 1.0 or less where L1 represents a length of a surface of the cylindrical body in contact with the partition plate along a nozzle longitudinal direction and L2 represents a distance between adjacent cylindrical bodies in the nozzle longitudinal direction.

8. The gas ejection nozzle according to any one of claims 1 to 7, wherein in an ejection velocity distribution of the gas along the nozzle longitudinal direction, a difference between a maximum value and a minimum value of an ejection velocity is within 11% with respect to an average ejection velocity.

9. A furnace comprising the gas discharge nozzle according to any one of claims 1 to 8,

and blowing a heating gas from the gas ejection nozzle to the resin film to perform a heating treatment.

10. A method for producing a processed film, comprising a step of blowing a gas onto a surface of a resin film by using the gas ejection nozzle according to any one of claims 1 to 8.

11. The method of manufacturing a processed film according to claim 10, wherein the gas is a heated gas.

Technical Field

The present invention relates to a gas ejection nozzle for blowing a gas onto a surface of a resin film, a furnace provided with the gas ejection nozzle, and a method for producing a processed film.

Background

In a process for producing a processed film in which a surface of a resin film is processed, for example, a liquid is applied to a long or web-shaped raw material of the resin film, and then the resin film is conveyed inside a drying furnace or the like while blowing a gas such as air or nitrogen gas on the surface of the resin film. When blowing a gas to the resin film to be conveyed, a gas ejection nozzle that extends in a direction orthogonal to the conveying direction of the resin film, that is, in the width direction of the resin film and ejects a gas perpendicularly toward the surface of the resin film is generally used in many cases. The gas is supplied to the gas ejection nozzle extending in the film width direction (i.e., the nozzle longitudinal direction).

Such a gas ejection nozzle bends a gas supplied in the nozzle longitudinal direction in a direction orthogonal to the supply direction, and blows the resin film. A baffle (buffer) or the like is provided in the nozzle in order to change the direction of the gas flow, but turbulence may occur due to the collision of the gas with the baffle, and the resin film to be blown may be damaged by the turbulence. As a gas ejection nozzle for preventing such damage and blowing a similar gas flow, patent document 1 discloses a gas ejection nozzle having an uneven surface cover formed in a wavy or zigzag shape by repeating unevenness along a longitudinal direction of the gas ejection nozzle (i.e., a width direction of a workpiece). The cross-sectional shape of the convex-concave surface cover along the length direction of the nozzle is triangular wave shape. The gas ejection nozzle has a nozzle box having a surface facing the workpiece as a gas ejection surface, and a slit-shaped opening provided in the nozzle box and extending in a width direction of the workpiece and through which the gas passes toward the gas ejection surface, and the uneven surface cover is provided so as to cover the opening in the nozzle box. The concave-convex surface cover covers the opening, but the cross-sectional shape is triangular wave-like, so that the gas can flow toward the opening from the end side (cover side) of the concave-convex surface cover in the direction orthogonal to the nozzle longitudinal direction (width direction of the gas ejection nozzle). Further, a gap is formed between the concave-convex surface cover and the inner wall of the nozzle box in the nozzle width direction. The gas supplied to the gas ejection nozzle flows from the slit to the side of the concave-convex surface cover, flows in the space between the concave-convex surface cover and the opening, passes through the opening, and is ejected from the gas ejection surface toward the workpiece. Further, patent document 1 discloses that a space between the opening and the gas ejection surface is a stabilization chamber or a pressure equalizing chamber for stabilizing the gas flow. Patent document 2 also discloses a gas discharge nozzle having a concave-convex surface cover. The gas discharge nozzle described in patent document 2 is a gas discharge nozzle in which the cross-sectional shape of the concave-convex surface cover is a sine wave shape or a trapezoidal shape.

Disclosure of Invention

Problems to be solved by the invention

The characteristics of a processed film produced by blowing a gas into a furnace such as a drying furnace are affected by the thermal history when the processed film passes through the inside of the furnace, and in order to obtain a processed film having uniform characteristics in the width direction of the film, it is necessary to make the heat exchange between the gas ejected from the gas ejection nozzle and the resin film uniform in the width direction of the resin film. Therefore, a rectifying mechanism needs to be provided in the gas ejection nozzle so that the gas ejection speed is constant along the width direction of the resin film.

However, the gas ejection nozzle that supplies ejection gas in the film width direction, i.e., the nozzle longitudinal direction includes a type that supplies gas from both sides in the nozzle longitudinal direction and a type that supplies gas from only one side in the nozzle longitudinal direction. As in patent documents 1 and 2, the following phenomenon occurs in a gas ejection nozzle that supplies gas from only one side in the nozzle longitudinal direction: the gas ejection velocity in the longitudinal direction of the nozzle at a position opposite to the gas supply side becomes greater than the gas ejection velocity at the gas supply side. The gas discharge nozzles disclosed in patent documents 1 and 2 can suppress the occurrence of local turbulence, but are not necessarily sufficient in terms of uniformity in the gas discharge velocity along the longitudinal direction of the nozzle.

The invention aims to provide a gas ejection nozzle for blowing gas to a resin film and having a uniform gas ejection speed along the length direction of the nozzle, a furnace provided with the gas ejection nozzle, and a method for manufacturing a processed film using the gas ejection nozzle.

Means for solving the problems

As a result of experiments and simulations, the inventors of the present application found that, when a concave-convex surface cover having a triangular wave-shaped cross section as shown in patent document 1 is used, the velocity of the gas flow flowing along the inclined surface facing the gas supply port is higher than the velocity of the gas flow not flowing along the inclined surface facing the gas supply port among the 2 inclined surfaces adjacent to each other constituting the concave-convex surface cover, and thereby studied the optimum angle for the inclination of the inclined surface and the uniformity of the gas ejection velocity along the nozzle longitudinal direction, and completed the present invention.

The gas ejection nozzle of the present invention is a gas ejection nozzle for blowing a gas onto a surface of a resin film, the gas ejection nozzle including: a housing provided so that a longitudinal direction of the gas discharge nozzle extends along a width direction of the resin film and having a gas discharge surface for discharging gas on a side surface facing the resin film; a gas supply port provided at one end of the housing and supplying a gas along a nozzle length direction; and 1 or more pressure equalizing chambers communicating from the gas supply port to a gas discharge surface, wherein a surface on the gas discharge surface side of at least 1 pressure equalizing chamber out of the 1 or more pressure equalizing chambers is formed by a partition plate, and a plurality of cylindrical bodies having openings at both ends are arranged on the partition plate along the nozzle longitudinal direction, the plurality of cylindrical bodies are arranged such that the axial direction of each cylindrical body is orthogonal to the nozzle longitudinal direction, an angle θ formed by a wall surface of the cylindrical body on a side close to the gas supply port among wall surfaces rising from the partition plate and the partition plate is an internal angle of the sectional shape of the cylindrical body and is in a range of 55 ° or more and 120 ° or less, and a gas flow hole further penetrating the partition plate is provided on a surface of the cylindrical body contacting the partition plate.

The oven of the present invention is provided with the gas ejection nozzle of the present invention, and performs a heating treatment by blowing a heating gas from the gas ejection nozzle to the resin film.

The method for producing a processed film of the present invention includes a step of blowing a gas to the resin film by the gas ejection nozzle of the present invention.

In the method for producing a processed film of the present invention, the gas is preferably a heated gas.

In the method for producing a processed film of the present invention, in the discharge velocity distribution of the gas along the longitudinal direction of the nozzle, the difference between the maximum value and the minimum value of the discharge velocity with respect to the average discharge velocity is preferably within 11%.

Effects of the invention

According to the present invention, a gas discharge nozzle in which the flow velocity of gas discharged from the gas discharge surface is uniform along the nozzle length direction can be obtained. By performing a heat treatment on the resin film using a furnace provided with the gas ejection nozzle, a processed film having uniform properties along the width direction of the film can be obtained.

Drawings

Fig. 1 is a view showing a typical gas ejection nozzle, where (a) is a perspective view and (b) is a sectional view.

Fig. 2 is a sectional view showing a gas ejection nozzle according to an embodiment of the present invention.

Fig. 3 is a schematic perspective view of the gas ejection nozzle shown in fig. 2.

Fig. 4 is a perspective view showing an example of the configuration and arrangement of the cylindrical body.

Fig. 5 is a perspective view showing an example of the configuration and arrangement of the cylindrical body.

Fig. 6 is a perspective view showing an example of the configuration and arrangement of the cylindrical body.

Fig. 7 is a sectional view showing a gas ejection nozzle according to another embodiment of the present invention.

Fig. 8 is a schematic perspective view of the gas ejection nozzle shown in fig. 7.

Fig. 9(a) to (c) are views showing the dimensions and angles of the respective portions of the tubular body.

Detailed Description

Next, preferred embodiments of the present invention will be described with reference to the drawings. Before describing the gas discharge nozzle according to the present invention, a general gas discharge nozzle will be described with reference to fig. 1.

The gas ejection nozzle 10 shown in fig. 1 is a gas ejection nozzle for blowing a gas such as air onto the surface of the resin film 50 conveyed in a drying furnace, a tenter oven for stretching, or the like, for example. As shown in fig. 1(a), an xyz orthogonal coordinate system is assumed in which the direction of conveyance of the resin film 50 is the z-axis direction, and the width direction of the resin film 50 orthogonal to the film conveyance direction is the x-axis direction. The y-axis direction is the height direction of the gas discharge nozzle 10. The gas ejection nozzles 10 are provided at a constant interval with respect to the surface of the resin film 50, and extend in the film width direction, i.e., the x-axis direction, of the entire width of the resin film 50. Therefore, the nozzle length direction is also referred to as the x-axis direction. The gas ejection nozzle 10 is configured to supply gas from one side in the nozzle longitudinal direction (x-axis direction) as shown in "gas supply direction" in fig. 1(a), and to eject gas parallel to the y-axis, which is a direction perpendicular to the surface of the resin film 50, over the entire width of the resin film 50 as shown in "ejection direction". The direction perpendicular to the nozzle length direction and parallel to the resin film 50 (i.e., the z direction) is referred to as the nozzle width direction.

Fig. 1(b) shows a cross-sectional structure of the gas ejection nozzle 10 in a direction parallel to the nozzle longitudinal direction and perpendicular to the surface of the resin film 50. The gas ejection nozzle 10 has a housing 11 whose longitudinal direction extends in the width direction of the resin film 50, and a gas supply port 12 is provided at the left end of the housing 11 in the drawing. An upper pressure equalizing chamber 13 is formed inside the housing 11 so as to be connected to the gas supply port 12. The height of the upper pressure equalizing chamber 13 decreases with distance from the gas supply port in the nozzle length direction. I.e. formed in a conical shape. In the gas ejection nozzle 10, the surface facing the surface of the resin film 50 is a gas ejection surface 14. Between the upper pressure-equalizing chamber 13 and the gas ejection surface 14, 3 lower pressure-equalizing chambers 15 are provided. In fig. 1(b), the gas discharge nozzle 10 provided with 3 lower pressure equalizing chambers 15 is illustrated as an example, but the number of the lower pressure equalizing chambers 15 is not limited thereto. When a plurality of lower pressure-equalizing chambers 15 are provided, the lower pressure-equalizing chambers 15 are arranged in the height direction of the gas discharge nozzle 10, and the lower pressure-equalizing chambers 15 are separated from each other by porous and air-permeable partitions 17 such as punched metal plates. The upper pressure equalizing chamber 13 and the lower pressure equalizing chamber 15 are also partitioned by a porous and air-permeable partition plate 16 such as a punched metal plate. The separators 16 and 17 are both provided parallel to the surface of the resin film 50, that is, parallel to the x-axis and z-axis. The entire outer walls of the upper pressure equalizing chamber 13 and the lower pressure equalizing chamber 15 constitute a casing 11 (i.e., a nozzle casing) of the gas discharge nozzle 10, and a gas discharge surface 14 is formed on a side surface of the casing 11 facing the resin film 50.

In the gas discharge nozzle 10 shown in fig. 1, porous and air- permeable partitions 16 and 17 are used, and therefore, the gas supply port 12 communicates with the gas discharge surface 14 via the upper pressure equalizing chamber 13 and the lower pressure equalizing chamber 15. The gas supplied from the gas supply port 12 flows in the upper pressure equalizing chamber 13 in the x direction as shown in the figure, passes through the partition plate 16, enters the lower pressure equalizing chamber 15, passes through the partition plate 17, gradually changes the flow direction, and is discharged from the gas discharge surface 14 as a gas flow perpendicular to the surface of the resin film 50.

Next, a gas discharge nozzle according to an embodiment of the present invention will be described. Fig. 2 is a sectional view of a gas discharge nozzle 20 according to an embodiment of the present invention, and fig. 3 is a schematic perspective view for explaining the structure of the gas discharge nozzle 20. The gas discharge nozzle 20 shown in fig. 2 and 3 is different from the gas discharge nozzle 10 shown in fig. 1 in that the structure of the casing 11, the gas supply port 12, the upper pressure equalizing chamber 13, the lower pressure equalizing chamber 15, and the partition plate 17 is the same as the structure of the gas discharge nozzle 10 shown in fig. 1, the partition plate 21 different from the partition plate shown in fig. 1 is used as the partition plate for partitioning the upper pressure equalizing chamber 13 and the lower pressure equalizing chamber 15, and a plurality of cylindrical bodies 22 are arranged on the surface of the partition plate 21 on the upper pressure equalizing chamber 13 side. The separator 21 and the cylindrical body 22 will be described in detail below.

The partition plate 21 constitutes a surface on the gas ejection surface 14 side in the upper pressure equalizing chamber 13. As the separator 21, a general plate member is used instead of a porous material such as a punched metal plate. The tubular body 22 is disposed in the upper pressure equalizing chamber 13 so that the axial direction of the tube is the nozzle width direction, i.e., the z direction. When the sectional shape of the cylindrical body 22 is a shape obtained when the cylindrical body 22 is cut on a plane orthogonal to the axial direction of the cylinder, the sectional shape of the cylindrical body 22 is a polygonal shape such as a triangle or a quadrangle. The cross-sectional shape of the cylindrical body 22 shown in fig. 3 is a quadrangle. Both ends of the cylindrical body 22, which are cylinders, are openings 23. The length (length in the nozzle width direction) of the cylindrical body 22 is smaller than the length in the nozzle width direction of the gas discharge nozzle 20, so that a space is formed between the side walls (walls on both end sides in the nozzle width direction) of the upper pressure equalizing chamber 13 and the opening 23 of the cylindrical body 22, and the gas supplied from the gas supply port 12 can flow from the space into the inside of the cylindrical body 22 through the opening 23. In the tubular body 22, a porous and air-permeable member such as a punched metal plate or a net (mesh) may be disposed in the opening 23. The direction of the surface on which the opening 23 is formed is not particularly limited, but is preferably a surface parallel to the nozzle longitudinal direction and substantially perpendicular to the partition plate 21.

Fig. 4 is a diagram for explaining the internal structure of the cylindrical body 22, and shows the partition plate 21 and the cylindrical body 22. In fig. 4, arrows indicate the flow direction of the gas supplied from the gas supply port 12 to the upper pressure equalizing chamber 13. For ease of illustration of the interior of the cartridge 22, in FIG. 4, the cartridge 22 is depicted as having a height greater than that shown in FIG. 3. However, since the height of the cylindrical body 22 can be appropriately set as long as it can be accommodated in the upper pressure equalizing chamber 13, the effect of the present invention can be exhibited by using either the cylindrical body 22 having the height shown in fig. 3 or the cylindrical body 22 having the height shown in fig. 4. The gas flow hole 24 is formed in the cylindrical body 22 at a position along the longitudinal center line of the gas discharge nozzle 20 so as to penetrate both the bottom surface of the cylindrical body 22 and the partition plate 21, which are surfaces of the cylindrical body 22 in contact with the partition plate 21. The position of the gas flow hole 24 does not necessarily need to be along the longitudinal center line of the gas ejection nozzle 20, but is preferably arranged on the longitudinal center line. In the configuration shown in fig. 4, the gas flow holes 24 are formed in a slit shape along the entire length of the nozzle longitudinal direction on the bottom surface of the tubular body 22. The partition plate 21 at the position where the cylindrical body 22 is not provided has no through-hole. As a result, in the gas discharge nozzle 20, the gas supplied from the gas supply port 12 to the upper pressure equalizing chamber 13 flows into the inside of the tubular bodies 22 through the openings 23 of the tubular bodies 22, flows into the lower pressure equalizing chamber 15 through the gas flow holes 24, and is discharged from the gas discharge surface 14.

Since the gas flow holes 24 are provided for each cylindrical body 22, a plurality of gas flow holes 24 are arranged along the nozzle length direction as viewed from the entire partition plate 21. In this case, the gas flow holes 24 are preferably arranged uniformly along the nozzle longitudinal direction, and therefore, the cylindrical bodies 22 are preferably arranged on the partition plate 21 so as to be in contact with each other or so as to be equally spaced from each other in the nozzle longitudinal direction.

In the gas discharge nozzle 20 of the present embodiment, each tubular body 22 has 2 wall surfaces rising from the partition plate 21, and of these, the wall surface 25 on the gas supply port 12 side is preferably an angle θ formed by the wall surface 25 and the partition plate 21, which is an inner angle of the cross-sectional shape of the tubular body 22, of about 90 °. More specifically, θ is 55 ° or more and 120 ° or less, preferably 60 ° or more and 110 ° or less, and more preferably 75 ° or more and 95 ° or less. According to the study of the inventors of the present application, it is clear from the following examples that: if the angle θ formed by the wall surface 25 and the partition plate 21 is within this angle range, the velocity distribution of the gas ejected from the gas ejection surface 14 becomes uniform over the entire length in the nozzle longitudinal direction.

In the above-described sub-example, the cylindrical body 22 is provided in the upper pressure-equalizing chamber 13, but the pressure-equalizing chamber in which the cylindrical body 22 is provided is not necessarily limited to the upper pressure-equalizing chamber 13. However, the most expected rectification effect by providing the cylindrical body 22 is when the cylindrical body 22 is provided in the pressure equalizing chamber adjacent to the gas supply port 12, and therefore, the cylindrical body 22 is preferably disposed in the upper pressure equalizing chamber 13. When the cylindrical body 22 is provided in the upper pressure equalizing chamber 13, the lower pressure equalizing chamber 15 does not necessarily need to be provided in the gas discharge nozzle 20, and the gas flowing out of the gas flow holes 24 may be directly blown onto the resin film 50 by using the partition plate 21 itself as the gas discharge surface 14. However, the lower pressure equalizing chamber 15 is preferably provided from the viewpoint of controllability of the gas flow discharged from the gas discharge surface 14.

In the configuration shown in fig. 2, 3, and 4, the cylindrical bodies 22 having a quadrangular cross section are disposed at the partition plate 21 so as to be spaced from each other, but the configuration and disposition of the cylindrical bodies 22 are not limited thereto. Fig. 5 shows another example of the structure and arrangement of the cylindrical body 22. In the configuration shown in fig. 5, the tubular bodies 22 having a quadrangular cross-sectional shape are disposed on the partition plate 21 in the nozzle longitudinal direction so as to be in contact with each other. The gas flow hole 24 is formed in a circular shape at a substantially central portion of the bottom surface of the cylindrical body 22, and the diameter of the gas flow hole 24 is smaller than the length of the bottom surface of the cylindrical body 22 in the nozzle longitudinal direction. In the tubular body 22 shown in fig. 5, an angle θ formed by the wall surface 25 rising from the separator 21 on the side of the gas supply port 12 among the wall surfaces and the separator 21 is 55 ° or more and 120 ° or less, preferably 60 ° or more and 110 ° or less, and more preferably 75 ° or more and 95 ° or less.

Fig. 6 shows still another example of the structure and arrangement of the tubular body 22. The configuration shown in fig. 6 is as follows: in the configuration shown in fig. 4, the cross-sectional shape of the tubular body 22 is changed from a quadrangle to a triangle. In the tubular body 22 shown in fig. 6, an angle θ formed by the wall surface 25 rising from the separator 21 on the side of the gas supply port 12 among the wall surfaces and the separator 21 is 55 ° or more and 120 ° or less, preferably 60 ° or more and 110 ° or less, and more preferably 75 ° or more and 95 ° or less.

Next, a gas discharge nozzle according to another embodiment of the present invention will be described. In the gas discharge nozzle 20 of the above-described embodiment, the upper pressure equalizing chamber 13 is formed in a tapered shape whose height decreases in the nozzle longitudinal direction when viewed from the gas supply port 12 side. However, in the present invention, the shape of the upper pressure equalizing chamber is not limited to the tapered shape. The gas discharge nozzle 30 according to the other embodiment of the present invention shown in fig. 7 has the same configuration as the gas discharge nozzle 20 shown in fig. 2 and 3, but is different from the gas discharge nozzle 20 shown in fig. 2 and 3 in that it includes an upper pressure equalizing chamber 32 having a constant height along the nozzle length direction. In addition, the adjacent cylindrical bodies 22 are provided so as to be in contact with each other, similarly to the gas discharge nozzle shown in fig. 5. Fig. 8 is a schematic perspective view for explaining the structure of the gas discharge nozzle 30 shown in fig. 7.

In the gas discharge nozzles 20 and 30 according to the present invention described above, the shape of the gas flow holes 24 is not particularly limited as long as they are in communication from the upper pressure equalizing chamber 13 to the lower pressure equalizing chamber 15 or the gas discharge surface 14, but a slit-like shape extending in the nozzle longitudinal direction as shown in fig. 4 or 6 is preferable. In addition, the opening area of the gas flow hole 24 is S for every 1 cylindrical body 22₁And the area of the surface of the cylindrical body 22 in contact with the separator 21 except the surfaces of the wall surfaces 22 and 25 in contact with the separator is S₂While, the aperture ratio S₁/S₂Preferably 0.85 or less.

The gas ejection nozzles 20 and 30 according to the present invention are configured such that the difference between the maximum value and the minimum value of the ejection velocity when the distribution of the ejection velocity of the gas is obtained along the nozzle longitudinal direction is approximately 14% or less, preferably 11% or less, with respect to the average ejection velocity, but the difference between the maximum value and the minimum value of the ejection velocity may be larger than this value depending on the type of the resin film 50 used as the target for ejecting the gas, and is not particularly limited. The ejection speed of the gas from the gas ejection surface 14 is preferably in a range of more than 0m/s and 20m/s or less, and more preferably in a range of more than 0m/s and 7m/s or less.

The gas ejection nozzles 20 and 30 according to the present invention are provided in, for example, a drying oven or a tenter oven, and are used to blow a gas such as air or nitrogen gas onto the surface of the resin film 50 when manufacturing a processed film. Specifically, the gas ejection nozzles 20 and 30 are used when the coating liquid is applied to the resin film 50 and then the resin film 50 is dried by blowing air in a drying oven. At least one of the following advantages is obtained by using the gas ejection nozzles 20 and 30 according to the present invention in a drying oven or a tenter oven when producing a processed film

(1) Obtaining a processed film with uniform surface roughness in the film width direction;

(2) obtaining a processed film with uniform thickness in the film width direction;

(3) obtaining a processed film in which micropores are uniformly formed in a film width direction in the case of forming a microporous film;

(4) the shaking of the film during conveying is reduced, the occurrence of film cracking is reduced, and the yield is improved;

(5) a processed film having uniform adhesion between the dried coating film and the resin film in the film width direction is obtained;

(6) a processed film having no appearance defects was obtained.