JP2002066419A - Coating apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coating apparatus which can stably and uniformly coat while preventing the occurrence of turbulent flow of a coating liquid. SOLUTION: The tip face of a first doctor edge tip 17 attached to a first doctor edge is made so that its curved face 23 present along the width direction of a flexible band-like support 19 is made bulgy toward the flexible band-like support 19. The tip face of a second doctor edge tip 18 attached to a second doctor edge is made so that a bulgy streak 24 present along the width direction of the flexible band-like support 19 is made bulgy toward the flexible band-like support 19. The bulgy streak 24 is formed so that arcs different in radius of curvature at the upstream and downstream sides are smoothly connected so as to have the same tangential line, forming a composite arc face having a wing-line-shaped cross section.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating apparatus for applying a thin layer to a traveling flexible belt-like support, and more particularly to a coating head for discharging a coating liquid.

[0002]

2. Description of the Related Art Generally, as a prior art of a coating apparatus for forming a thin layer, there is one disclosed in Japanese Patent Publication No. Hei 6-77712 (hereinafter referred to as a first prior art).

[0003] The coating apparatus shown in the first prior art has a coating head as shown in FIG. 6, the coating head comprising a back edge 2 and a first doctor edge 3 forming a first slot 1, A second doctor edge 5 forming a second slot 4 together with the first doctor edge 3 is provided.

A first slot 1 and a first slot 1 are provided inside the coating head.
Pockets 6a and 6b each having a substantially circular cross section communicating with the second slot 4 are formed. Then, the coating liquid is sent from the liquid supply means (not shown) in the directions of arrows B1 and B2 via the pipes 7a and 7b, respectively, and is stored in the pockets 6a and 6b. It is pushed out to each outlet of the two slots 4, and the direction of the arrow C1,
It is configured to be discharged to C2.

[0005] The flexible belt-shaped support 8 is fed from the back edge 2 side to the back edge 2, the first doctor edge 3, and the second doctor edge 5 by a feeding means of the flexible belt-shaped support 8 not shown. The vehicle travels in the arrow direction A.

When the flexible belt-shaped support 8 travels, as shown in FIG. 7, the first coating liquid 91 in the pocket 6a is
The ink is discharged from the slot 1 and applied to one surface of the flexible belt-shaped support 8. After that, the second coating liquid 92 which is located on the downstream side in the traveling direction of the flexible belt-shaped support 8 and is pushed out from the inside of the pocket 6b to the outlet of the second slot 4 is used for the first coating liquid 91. Overlaid on top. As described above, when the flexible belt-shaped support 8 travels, the coating liquids 91 and 92 are discharged back and forth, and the two layers of the coating liquids 91 and 9 are applied to the flexible belt-shaped support 8.
2 is applied.

[0007]

As described above, the coating liquids 91 and 9 are supplied from the first slot 1 and the second slot 4 as described above.
The following problems have occurred when 2 is ejected and applied to the flexible belt-shaped support 8. For example, as shown in FIG. 7, when the coating liquid 92 of the second layer flows out of the outlet of the second slot 4 onto the flexible belt-shaped support 8, the distal end surface of the second doctor edge 5 and the flexible belt-shaped A turbulent flow 93 as a turbulent flow is generated between the support 8 and the support 8, so that the speed of the outflow of the coating liquid 92 becomes unstable, and the thickness of the coating liquid 92 becomes nonuniform. For this reason, it was not possible to apply a uniform coating solution to the flexible belt-like support 8. In addition, since the second slot 4 is inclined at an angle opposite to the running direction of the flexible band-shaped support 8, it also contributes to the generation of the vortex 93 in the coating liquid 92. Of course, such a turbulent flow of the coating liquid 92 is smaller than the second-layer coating liquid 92 discharged from the second slot 4,
The same occurs in the first-layer coating liquid 91 discharged from the first slot 1, which is one of the causes of forming an uneven film thickness.

In view of the above circumstances, the present invention can prevent turbulence from occurring in a coating liquid discharged from a slot, and can apply a coating liquid stably and uniformly to a flexible belt-shaped support. It is an object to provide a coating device.

[0009]

Means for Solving the Problems To solve the above problems, the present invention employs the following means. Claim 1
In the invention described, the coating head includes a coating head that applies a coating liquid on a flexible belt-shaped support that travels in one direction, and the coating heads are sequentially arranged in the traveling direction of the flexible belt-shaped support. Having at least two members, a slot through which the coating liquid flows toward the flexible strip-shaped support is formed between the members, and an outlet of the slot is opened at a tip end of the member. In the coating device, the coating liquid is applied to the flexible belt-shaped support so that the coating liquid flows out of the two adjacent members, and a distal end surface of a member arranged on a downstream side includes the The ridges along the width direction of the flexible band-shaped support are projected toward the flexible band-shaped support, and the ridges have different curvature radii on the upstream side and the downstream side having the same tangent to each other. And wing-shaped composites that are connected smoothly and smoothly Characterized in that it is a comment.

[0010] As described above, since the distal end surface of the member arranged on the downstream side forms a compound arc surface having a wing-shaped cross section as described above, the member arranged on the downstream side receives the coating liquid from the slot. The coating liquid can be smoothly flowed out at the tip end surface, and turbulence is prevented from being generated in the coating liquid, so that the coating liquid can be uniformly applied to the flexible belt-shaped support. At this time, the radius of curvature Ru on the upstream side of the ridge and the radius of curvature Rd on the downstream side are
Is less than Ru <Rd, and 2 mm ≦ Ru ≦ 20 m
By setting m (Rd <∞), stable and uniform application can be surely realized.

According to the present invention, the coating head has three members sequentially arranged in the traveling direction of the flexible strip-shaped support, and the three members are respectively arranged in the traveling direction. The back edge, the first doctor edge, and the second doctor edge are sequentially formed, and a first slot is formed between the back edge and the first doctor edge, and the distal end surface of the first doctor edge is curved. The second doctor edge has a convex surface, and the distal end surface of the second doctor edge is the convex arc, and the convex arc is the composite arc surface having a wing-shaped cross section.

As described above, since the distal end surface of the first doctor edge has a curved surface and the distal end surface of the second doctor edge has a compound arc surface having a wing-shaped cross section, the coating liquid from the first and second slots is formed. Can flow out smoothly. In particular, it is possible to prevent a turbulent flow such as a vortex from being generated in the coating liquid between the flexible band-shaped support and the second doctor edge where the flexible band-shaped support is separated from the coating head. The coating liquid can be uniformly applied to the flexible belt-shaped support.

At this time, the angle θ between the second slot formed by the first doctor edge and the second doctor edge and the direction of the flexible belt-like support toward the second doctor edge is: 90 ° ≦ θ <≦ 120
°, the coating solution can be smoothly pushed out along the running direction of the flexible belt-shaped support without opposing the running direction of the flexible band-shaped support, and the turbulent flow can be more effectively prevented. Things. Further, the radius of curvature Rd of the first doctor edge on the downstream side of the curved surface is R1,
The radius of curvature Ru on the upstream side is R2, and the radius of curvature Ru on the upstream side of the ridge of the second doctor edge is R3.
The radius of curvature Rd on the downstream side is R4. These relationships are R1 <R2, R3 <R4, and 2 mm ≦ R1, R
When 3 ≦ 20 mm (R2, R4 <∞), not only the coating liquid from the second slot but also the coating liquid from the first slot can be stably applied with a uniform thickness.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to FIGS. As shown in FIGS. 1 and 2, the coating apparatus has a coating head 10, and the coating head 10 forms a back edge 13 forming a first slot 11.
And the first doctor edge 14 and the first doctor edge 1
4 together with a second doctor edge 15 forming a second slot 12. Further, a feeding means (not shown) for feeding the flexible belt-shaped support 19 in the traveling direction A is provided. The back edge 13, the first and second doctor edges 14, 15 are sequentially arranged along the traveling direction A of the flexible band-shaped support 19, and the front edge of the back edge 16, which is made of cemented carbide, is disposed at the front end. The first and second doctor edge tips 17, 18 are respectively mounted.

When the flexible belt-shaped support 19 travels, the coating liquids 20A, 20B are supplied by a liquid supply means (not shown).
Is supplied, and the coating liquids 20A and 20B are
22 and the first slot 11 and the second slot 12, the coating liquid 2 is applied to one surface of the flexible belt-shaped support 19.
0A and 20B are configured to be applied in an overlapping manner. In this example, the coating liquid in this case is for forming a base material sheet used for the green sheet of the multilayer ceramic capacitor. For example, the liquid containing the dielectric ceramic powder, and the composition thereof were slightly changed. It consists of two types, such as a dielectric-containing liquid.

Further, as shown in FIG. 3, a curved surface 23 along the width direction of the flexible band-shaped support 19 can be formed on the distal end face of the first doctor edge tip 17 attached to the first doctor edge 14. A curved surface 23 protruding toward the flexible band-shaped support 19 and having a curved surface 23 in which arcs having different radii of curvature on the upstream side 23a and the downstream side 23b have the same tangent to each other and are smoothly connected to each other; Have been. At this time, if the radius of curvature of the downstream side 23b of the curved surface 23 is represented by R1, and the radius of curvature of the upstream side 23a is represented by R2, the relationship is R1 <R2. However, 2 ≦ R1 ≦ 20 (mm), R2 <
∞.

Further, the tip surface of the second doctor edge tip 18 attached to the second doctor edge 15 is shown in FIG.
As shown in the figure, a ridge 24 along the width direction of the flexible band-shaped support 19 is projected toward the flexible band-shaped support 19, and the ridge 24 has a different curvature between the upstream side 24a and the downstream side 24b. It is a composite arc surface having a wing-shaped cross section formed by smoothly connecting arcs of radii having the same tangent to each other. At this time, the height dimension h between the end of the upstream side 24a and the ridge top 24c in the ridge 24 is 0 <h ≦ 1 (m
m). Also, the upstream side 24 of the ridge 24
Assuming that the radius of curvature of a is R3 and the radius of curvature of the downstream side 24b is R4, the relationship of R3 <R4 is established. Where 2 ≦ R
3 ≦ 20 (mm) and R4 <∞.

Further, the first doctor edge 14 and the second
Second slot 1 formed by doctor edge 15
2 and the direction of the flexible band-shaped support 19 toward the second doctor edge 15 are 90 ° ≦ θ <≦ 120 °
Is desirably within the range.

In the coating apparatus having such a configuration, when the flexible belt-shaped support 19 runs, the coating liquids 20A and 20B are respectively supplied by liquid supply means (not shown), and the coating liquids 20A and 20B are stored in the pockets 21 and 20. 22 and the first slot 11 and the second slot 12, and are applied from the respective outlets in a state of being sequentially overlapped on one surface of the flexible band-shaped support 19.

At the time of this application, of the first doctor edge 14 and the second doctor edge 15 forming the second slot 12, the tip of the second doctor edge tip 18 attached to the tip of the second doctor edge 15. As mentioned above,
The upstream side 24a and the downstream side 24b have different curvature radii, and the curvature radius R on the downstream side of the curvature radius R3 on the upstream side.
4, the coating liquid from the outlet 12a of the second slot 12 is applied to the tip 1 of the second doctor edge as shown in FIG.
8 can be smoothly discharged along the front end surface. Therefore, it is possible to prevent the vortex as a turbulent flow from being generated in the coating liquid 20 </ b> B pushed out from the second slot 12.

In addition, the first doctor edge 14 and the second
Second slot 1 formed by doctor edge 15
2 and the direction of the flexible band-shaped support 19 toward the second doctor edge 15 are 90 ° ≦ θ <≦ 120 °
, The coating solution 20B can be smoothly pushed out along the running direction of the flexible band-shaped support 19 without opposing the running direction of the flexible band-shaped support 19, and the turbulent flow can be more effectively prevented. Things.

Further, of the back edge 13 and the first doctor edge 14 forming the first slot 11, the tip surface of the first doctor edge tip 17 attached to the tip of the first doctor edge 14 is the same as that described above. Like the upstream side 23a
And the downstream side 23b have different curvature radii, and form a composite arc surface in which the curvature radius of the upstream side 23a is larger than the curvature radius of the downstream side 23b, so that the coating liquid 20A from the first slot 11 1st doctor edge tip 1
7 can smoothly flow out at the tip end surface.

Therefore, according to the present embodiment, not only the turbulence of the coating solution 20B pushed out from the second slot 12 can be prevented, but also the turbulence of the coating solution 20A pushed out from the first slot 11 is prevented. As a result, the two coating solutions 20A and 20B can be uniformly and stably applied to the flexible belt-like support 19, and a uniform and uniform two-layer thin film layer can be reliably obtained. .

FIG. 5 shows another embodiment of the coating apparatus according to the present invention. In this embodiment, the coating head 10 is provided with a back edge 32 and a doctor edge 33 forming a slot 31, and a back edge tip 34 and a doctor edge tip 35 are attached to these tips, for example, flexible. It is configured so that only the coating solution 20A is applied to the belt-like support 19.

The tip surface of the doctor edge tip 35 attached to the tip of the doctor edge 33 is shown in FIG.
As shown in (1), the protruding ridge 36 protrudes from the application surface of the flexible band-shaped support 19 from the upstream side to the downstream side in the running direction A of the flexible band-shaped support 19. This ridge 36
Has a different radius of curvature on its upstream side 36a and downstream side 36b, and is formed in a compound arcuate surface having a wing-line cross-section by being connected to each other. In this case, the height dimension h between the edge of the upstream side 36a of the convex ridge 36 and the convex top 36c is 0 <h ≦ 1 (mm), and the radius of curvature of the upstream side 36a of the convex ridge 36 is R5,
Assuming that the radius of curvature of the downstream side 36b is R6, the relationship of R5 <R6 holds, and the flexible band-shaped support 19 is expanded along the running direction. However, 2 ≦ R5 ≦ 2
0 (mm), R6 <∞.

According to this embodiment, when the flexible belt-shaped support 19 travels, the coating solution 20A is pushed out of the slot 31 to be applied to one surface of the flexible belt-shaped support 19, The distal end face of the doctor edge tip 35 attached to the doctor edge 33 has a different radius of curvature between the upstream side 36a and the downstream side 36b and the upstream side 3a.
6a, the curvature radius of the downstream side 36b is larger than that of the curvature radius of the composite arc surface having a wing-shaped cross section.
The coating liquid 20A from the slot 31 can smoothly flow out at the distal end surface of the doctor edge tip 35, and even when only one type of coating liquid 20A is applied, turbulence occurs in the coating liquid 20A. Can be prevented, the coating can be applied with a uniform film thickness, and basically the same operation and effect as in the above-described embodiment can be obtained.

In this embodiment, an example is shown in which the present invention is applied to a base material sheet of a green sheet in a multilayer ceramic capacitor. It can be applied to sheets as well as magnetic coating solutions,
The present invention can also be applied to those which form a magnetic tape, various photographic films, photographic paper and the like by applying a photographic photosensitive coating solution or the like.

In the embodiment, the curved surfaces 23 and the ridges 24 formed on the first and second doctor edge tips 17 and 18, and the ridge 36 formed on the doctor edge tip 35.
Although no specific numerical value is described for the radius of curvature of, the material and traveling speed of the flexible belt-shaped support member 8 and the coating liquids 20A and 20A are not described.
It is desirable that the material be appropriately selected according to the constituent material of OB, its discharge pressure, discharge amount, and the like.

[0029]

As described above, according to the first aspect of the present invention, the distal end surface of the member disposed on the downstream side is constituted by the composite arc surface having the wing-shaped cross section as described above.
The coating liquid from the slot can smoothly flow out at the tip end surface of the member, and turbulence can be prevented from being generated in the coating liquid, and the coating liquid can be applied with a uniform film thickness. In particular, according to the second aspect, stable and uniform application can be reliably realized.

According to the third aspect, the distal end surface of the first doctor edge forms a curved surface, the distal end surface of the second doctor edge forms a composite arc surface having a wing-shaped cross section, and Since the coating liquid is configured to smoothly flow out along the tip surfaces of the first and second doctor edges, it is possible to prevent generation of a turbulent flow as a turbulent flow particularly in the coating liquid pushed out from the second slot. Thus, there is an effect that stable application can be realized with a uniform film thickness.

According to the fourth and fifth aspects, coating can be performed with a more uniform thickness and more stably.

[Brief description of the drawings]

FIG. 1 is a perspective view of a coating head showing one embodiment of a coating device according to the present invention.

FIG. 2 is an explanatory diagram showing a relationship between a coating head and a flexible belt-shaped support.

FIG. 3 is an enlarged explanatory view showing a main part of the present invention.

FIG. 4 is an explanatory diagram of an operation in a coating state when the flexible belt-shaped support is running.

FIG. 5 is a schematic view showing another embodiment of the coating apparatus according to the present invention.

FIG. 6 is a schematic view showing a conventional coating apparatus.

FIG. 7 is an explanatory view showing a problem in a conventional coating apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 ... 1st slot 12 ... 2nd slot 13 ... Back edge 14 ... 1st doctor edge 15 ... 2nd doctor edge 16 ... Back edge tip 17 ... 1st doctor edge tip 18 ... 2nd doctor edge tip 19 ... Flexibility Band-shaped support A: running direction of the flexible band-shaped support 20A, 20B: coating liquid 23: curved surface at the tip of the first doctor edge 23a: upstream side of the curved surface 23b: downstream side of the curved surface 24: second doctor edge Tip ridge 24a ... Upstream of ridge 24b ... Downstream of ridge 31 ... Slot 32 ... Back edge 33 ... Doctor edge 34 ... Back edge tip 35 ... Doctor edge tip 36 ... Protrusion 36a ... Upstream of ridge 36b: Downstream side of the ridge 36c: Top of the ridge

Claims (5)

[Claims] 1. A coating head for applying a coating liquid on a flexible belt-like support running in one direction, wherein the coating heads are sequentially arranged in the running direction of the flexible belt-like support. A slot having at least two members, wherein the coating liquid flows between the members toward the flexible belt-shaped support, is formed from an outlet of the slot opened at a tip of the member. A coating apparatus configured so that a coating liquid flows out and is applied to the flexible belt-shaped support, wherein a tip surface of a member arranged on a downstream side between two adjacent members is the flexible member. The ridges along the width direction of the flexible band-shaped support are projected toward the flexible band-shaped support, and the ridges have different curvature radii on the upstream side and the downstream side so that they have the same tangent to each other. Composite arc with wing-shaped cross-section formed smoothly connected Coating apparatus characterized by being with. 2. The relationship between the curvature radius Ru on the upstream side of the ridge and the curvature radius Rd on the downstream side is such that Ru <Rd and 2
2. The coating apparatus according to claim 1, wherein mm ≦ Ru ≦ 20 mm (Rd <∞). 3. The coating head includes three members sequentially arranged in the traveling direction of the flexible belt-shaped support,
The three members are respectively a back edge, a first doctor edge, and a second doctor edge in the running direction, and a first slot is formed between the back edge and the first doctor edge, A second slot is formed between the first doctor edge and the second doctor edge, the tip surface of the first doctor edge forms a curved surface,
2. The coating apparatus according to claim 1, wherein the distal end surface of the second doctor edge forms the ridge, and the ridge is the composite arc surface having a wing-shaped cross section. 3. 4. The second slot formed by the first doctor edge and the second doctor edge,
The coating apparatus according to claim 3, wherein an angle θ formed between the direction of the flexible belt-shaped support body and the direction of the second doctor edge is set in a range of 90 ° ≦ θ <≦ 120 °. . 5. A curvature radius Rd on the downstream side of the curved surface of the first doctor edge is R1, and a curvature radius R on the upstream side is 5.
u is R2, the radius of curvature Ru on the upstream side of the ridge of the second doctor edge is R3, and the radius of curvature R on the downstream side is R3.
Let d be R4. These relationships are R1 <R2, R3 <R
4 and 2 mm ≦ R1, R3 ≦ 20 mm (R2, R4
The coating device according to claim 3, wherein <る こ と).