JPH11207248A - Coating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent thickness distribution in a width direction of a single striped coating film from becoming extremely thick on an edge part and prevent a trouble wherein a small amount of a coating liquid is transferred to a non- coating striped part and other troubles from occurring even if problems of thickness distribution are solved. SOLUTION: A coating object matter wherein thickness distribution in a width direction of a single striped coating film is prevented from becoming extremely thick on an edge part as compared with a center part and even a small amount of coating liquid is prevented from being transferred on a striped non-coating part is obtained by bringing a coating object matter 1 and a gravure roll 6 into contact with each other by interposing a required number of masks 8 having required dimensions between the coating object matter 1 and the gravure roll 6. When a continuous coating object matter is wound on a tubular cylindrical core, extreme partial rise due to coating thickness difference is avoided so that deterioration of dimensional accuracy and damage of the coating object matter due to elongation induced at a rising part can be eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating method for forming a stripe-shaped coating film in the longitudinal direction of a continuous object to be coated.

[0002]

2. Description of the Related Art Conventionally, as a coating method for forming a continuous strip-shaped coating film in a longitudinal direction on a continuous coating object, as shown in FIG.
Then, a stripe-shaped groove 12 is formed on the circumference, and the surplus application liquid in the groove and the surface of the gravure roll 14 is scraped off using a comb-shaped doctor blade 13 corresponding to the groove. There was a method of applying by contacting a gravure roll that rotates in the forward or reverse direction with respect to the transport direction, but the dimensions of the groove of the gravure roll and the dimensions of the comb-shaped doctor blade that corresponds to this gravure roll completely match If the doctor blade does not reliably hit the gravure roll, the excess coating liquid may be left unscrewed. As shown in FIG. 7, the edge portion 18 was thicker than the central portion 19 as shown in FIG. When the object to be coated is wound around a cylindrical core by such a conventional method, as shown in FIG. 8, the thick portion 18 of the stripe-shaped edge has an extremely large thickness compared to the central portion 19. In this case, there is a problem that the object to be coated in this portion is stretched to cause dimensional defects, and in an extreme case, the object to be coated is damaged.

As another method, as shown in FIG. 9, a flat portion 16 without gravure engraving is provided on the object 15 to be continuously conveyed, in a stripe shape in the circumferential direction of the surface, and the surplus surface is removed. There is also a method in which the coating liquid is scraped off and the gravure roll 17 rotating in the forward direction or the reverse direction with respect to the transport direction of the object to be coated is brought into contact with the gravure roll 17 to apply the coating liquid. However, since a small amount of coating liquid remaining on a flat portion without gravure engraving is transferred to the object to be coated on the surface of the gravure roll from which the excess coating liquid has been scraped off with a doctor blade, the metal foil is removed by such a conventional method. A metal thin film 21 is formed on the surface or a surface of a support 20 such as paper or a plastic film as shown in FIG. When a coating film 22 is formed in the shape of a stripe and an attempt is made to make electrical contact with the portion 23 where the striped metal surface is exposed, a small amount of insulator or Due to the presence of the coating liquid 24 serving as a dielectric, there have been problems such as an increase in the resistance of the contact portion and no contact at all.

[0004]

In the coating method of the present invention, a stripe-shaped coating film which is continuous in the longitudinal direction and which does not increase the coating thickness at the edge portion and does not transfer a small amount of coating liquid to the coated portion is formed. The purpose is to:

[0005]

SUMMARY OF THE INVENTION In order to solve this problem, the present invention relates to a method of contacting an object to be coated with a gravure roll through a mask having a necessary number and dimensions between the object and the gravure roll. It was done. According to the present invention, it is possible to form a stripe-shaped coating film continuous in the longitudinal direction in which the coating thickness at the edge portion does not increase and the coating portion does not include a trace amount of the coating liquid.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is characterized in that the surface of an object to be continuously conveyed is rotated in a forward or reverse direction with respect to the conveying direction of the object to be applied, In the method of applying by contacting a gravure roll with a coating liquid adhered thereto, providing a mask on a part or a plurality of parts in the axial direction of the gravure roll between the object to be coated and the gravure roll in the contact part, After the excess coating liquid is removed by the doctor blade, the coating liquid remaining on the surface of the gravure roll does not come into contact with the workpiece by the mask, and is applied to the surface of the workpiece in contact with the mask. The liquid is not applied, and the coating liquid on the gravure roll surface is applied to the object to be coated in the portion without the mask. At this time, the edge portion of the stripe-shaped coating film has a large coating thickness due to a small amount of coating liquid formed at the edge portion of the mask, but the thickness can be reduced as compared with the coating method according to the conventional method.

According to a second aspect of the present invention, a flat portion without gravure engraving is provided in the circumferential direction of the surface of the gravure roll so as to be at the same position as the mask. Due to this, the amount of the coating solution adhering to the gravure roll surface in the portion in contact with the mask is small,
The coating liquid pool that forms at the edge of the mask is reduced,
The coating thickness at the edge portion can be flattened.

According to a third aspect of the present invention, there is provided a gravure roll having a flat portion without gravure engraving having a width equal to or larger than a dimension of a contact portion of the mask with the gravure roll. Since there is no gravure engraving on the surface of the gravure roll in contact with the gravure roll, there is almost no coating liquid on the flat part surface after scraping off the excess coating liquid with a doctor blade, and coating liquid accumulation occurs at the edge of the mask Therefore, the coating thickness at the edge portion of the stripe-shaped coating film does not increase.

An embodiment of the present invention will be described below with reference to FIGS. (Embodiment 1) FIGS. 1 and 2 show a coating method according to claim 1 of the present invention. FIG. 1 is a perspective view, FIG. 2 is a side view, and in FIGS. They are supported by rolls 2 and 3, and are conveyed from left rear to right front in FIG. 1 and from left to right in FIG. The gravure roll 6, on which gravure engraving is applied almost entirely, is provided with the coating liquid 5 stored in the coating liquid reservoir 4.
, And is rotated in the direction of the arrow, and the excess coating solution is scraped off by the doctor blade 7 and is in contact with the object 1 through the mask 8. The mask 8 has an action of forming a stripe-shaped non-coating portion, and is preferably made of a material having a low friction coefficient and good abrasion resistance with respect to friction with the gravure roll 6 and the object to be coated, Metals are preferred in terms of wear resistance and dimensional accuracy. The thickness of the mask 8 is preferably as thin as possible in terms of dimensional accuracy, but is preferably from 10 to 100 μm in terms of life due to abrasion and ease of handling.

(Embodiment 2) FIG. 3 is a front view of a coating method according to a second embodiment of the present invention. In FIG. 3, a part of a portion of the surface of the gravure roll 6 which comes into contact with the mask 8 is shown. A flat portion 9 without gravure engraving is provided, and the flat portion 9 without gravure engraving has an extremely small amount of the coating solution adhering to the surface as compared with the gravure engraved portion 10 and thus has a mask Pool 1 caused by contact with water
1 has the effect of reducing the coating thickness at the edge of the stripe-shaped coating film. If a striped non-coated portion having the required dimensions can be obtained, a flat portion 9 without gravure engraving can be obtained. The dimensional relationship between the gravure roll and the mask 8 in the axial direction can be freely set.

(Embodiment 3) FIGS. 4 and 5 are enlarged views of a contact portion between a gravure roll 6 and a mask 8 in a coating method according to a third embodiment of the present invention. The dimension in the axial direction of the gravure roll of the flat portion 9 without gravure engraving provided in 6 is the same as the dimension of the portion of the mask 8 that comes into contact with the gravure roll 6, and FIG.
In (a) and (b), the dimension in the axial direction of the gravure roll of the flat portion 9 having no gravure engraving provided on the gravure roll 6 is larger than the dimension of the portion of the mask 8 which is in contact with the gravure roll 6. In each case,
The entire surface of the gravure roll 6 in contact with the mask 8 becomes a flat portion 9 without gravure engraving, and almost no liquid pool is generated at the edge of the mask 8 in contact with the mask 8, and the coating thickness at the edge of the stripe-shaped coating film is reduced. It has the effect of lowering.

[0012]

Next, specific examples of the present invention will be described.

(Example 1) The number of meshes is 20 over the entire surface.
0 mesh, 25 μm depth, gravure engraving with pyramid shape, diameter 60 mm, surface length 600
mm gravure roll, 48 stainless steel masks having a dimension of 1 mm in the gravure roll axis direction and a thickness of 20 μm are provided at intervals of 10 mm in the gravure roll axis direction.
The gravure roll was provided at a holding angle of 30 degrees, the rotation speed of the gravure roll was 200 r / m, and a doctor blade made of 0.15 mm-thick Swedish steel was used for scraping off excess liquid. Without diluting the UV-curable acrylate resin in a solvent, a polyethylene terephthalate film having a thickness of 5 μm and a width of 500 mm was applied to the object to be applied, and a length of 2000 m was applied at an application speed of 50 m / min. Wound on the core. The coating thickness at this time was 2.0 μm at the center in the width direction of one stripe and 2.5 μm at the edge. Further, there was no adhesion of the coating liquid to the surface of the film which should be the non-coated portion formed by the mask.

As a comparison, a gravure roll having a dimension of 1 mm in the gravure roll axis direction and a depth of 1 mm without a mask was provided.
mm, and the thickness of the coating film applied under the same configuration and conditions as in Example 1 was 2 except that a doctor blade adapted to the shape and size was used. 0.0 μm, and the edge portion was 3.0 μm.

(Example 2) The surface portion of the gravure roll in contact with the mask has a dimension in the gravure roll axial direction of 0.8.
The coating was carried out under the same configuration and conditions as in Example 1 except that the surface was flat without gravure engraving so that the thickness became mm. The coating thickness at this time was 2.0 μm at the center in the width direction of one stripe, and 2.3 μm at the edge. Further, there was no adhesion of the coating solution to the surface of the polyethylene terephthalate film which should be the non-coated portion formed by the mask.

(Example 3) The surface portion of the gravure roll in contact with the mask has a dimension in the gravure roll axial direction of 1.1.
The coating was carried out under the same configuration and conditions as in Example 1 except that the surface was flat without gravure engraving so that the thickness became mm. The coating thickness at this time was 2.0 μm at the center in the width direction of one stripe and 2.1 μm at the edge. Further, there was no adhesion of the coating liquid to the surface of the polyethylene terephthalate film which should be an uncoated portion formed by the mask.

[0017]

As described above, according to the present invention, by providing a mask between the object to be coated and the gravure roll, the coating thickness at the edge portion is extremely larger than the coating thickness at the central portion in the width direction of one stripe. It is not thickened, and in the state where it is wound on a cylindrical core, deterioration of dimensional accuracy due to elongation of the application object caused by locally increasing the application thickness locally and breakage of the object to be applied are eliminated, and By obtaining a striped coating film with no coating liquid adhered to the surface of the object to be coated, which should be the non-coated part, a metal thin film can be formed on the surface of a metal foil or the surface of a support such as paper or plastic film. When the coating liquid is applied in a stripe shape to the surface of the metal thin film for the purpose of insulator or dielectric, the electrical contact is made with the exposed part of the stripe-shaped metal surface. Or resistance becomes high of ECTS part, it is solved the problem, such as it is not possible to completely contact.

Furthermore, by providing a flat portion without gravure engraving in the circumferential direction of the gravure roll at the portion in contact with the mask, the coating thickness at the edge portion with respect to the coating thickness at the central portion in the width direction of one stripe is provided. The effect of further reducing the degree of increase in the thickness of the film is obtained.

Furthermore, the flat portion without the gravure engraving is made equal to or larger than the dimension of the contact portion between the mask and the gravure roll in the gravure roll axial direction, and the mask is made flat without the gravure engraving of the gravure roll. By providing the stripe in the portion, an effect of making the coating thickness of the central portion in the width direction of one stripe substantially equal to the coating thickness of the edge portion can be obtained.

The gravure roll described in the examples,
The specifications of the doctor blade and the like, the materials such as the object to be coated and the coating liquid, and the coating conditions are examples of the embodiment, and are not limited thereto.

[Brief description of the drawings]

FIG. 1 is a perspective view of a coating method according to a first embodiment of the present invention.

FIG. 2 is a side view of the coating method according to the first embodiment of the present invention.

FIG. 3 is a front view of a coating method according to a second embodiment of the present invention.

FIG. 4 is an explanatory view of a gravure roll and a mask according to a third embodiment of the present invention.

FIGS. 5A and 5B are explanatory views of a gravure roll and a mask according to a third embodiment of the present invention.

FIG. 6 is a perspective view of a conventional coating method.

FIG. 7 is a cross-sectional view showing a coating state by a conventional coating method.

FIG. 8 is a diagram showing a state in which a non-coated material according to a conventional coating method is wound up.

FIG. 9 is a perspective view of a conventional coating method different from FIG. 7;

FIG. 10 is a sectional view showing an application state by the conventional application method of FIG. 9;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Coated object 6 Gravure roll 8 Mask 9 Flat part without gravure engraving

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Takashi Fujiwara 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (3)

[Claims] 1. A gravure roll that rotates in a forward or reverse direction with respect to the direction of conveyance of an object to be coated, one surface of which is continuously conveyed, and one surface of which is in a free state, and the surface of the object to which a coating liquid is applied is conveyed. A part of the gravure roll between the axial direction, or a plurality of portions provided with a mask to contact the gravure roll with the object to be coated, continuous in the longitudinal direction to a portion or a plurality of portions of the object to be coated A coating method for forming a non-coated portion. 2. A coating method according to claim 1, wherein a gravure roll having a flat portion without gravure engraving in a circumferential direction of a portion of the gravure roll contacting the mask is used. 3. The flat portion without the gravure engraving has a dimension equal to or larger than the dimension of the contact portion between the mask and the gravure roll in the direction of the gravure roll axis, and the mask is flat without the gravure engraving of the gravure roll. 3. The coating method according to claim 2, wherein the coating method is located within a portion.