JP2006289328A - Knife coating apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a knife coating apparatus capable of uniformly and smoothly applying a coating liquid having viscosity ranging from high viscosity to low viscosity while easily controlling a coating film to have film thickness ranging from thin thickness to thick thickness. <P>SOLUTION: The knife coating apparatus has a backup roll formed with a base material carrying passage on the outer peripheral surface and a liquid supply part in the base material crossing direction on the base material carrying passage, having an R-shape to reduce liquid retaining volume from the inlet of the liquid toward the outlet in the liquid supply part and provided in the base material crossing direction by providing a fine interval with the knife having the knife tip part provided to make 15-45° angle from the vertically below part of the backup roll toward the base material advancing direction and a control mechanism capable of controlling the interval between the backup roll and the knife tip part toward the center part of the backup roll in the knife and the liquid stopping part is provided. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a knife coating apparatus for uniformly forming a coating liquid from a low viscosity to a high viscosity on a surface of a base material supported on an outer peripheral surface of a backup roll and from a thin film to a thick film. is there.

This kind of conventional knife coating device did not have an R shape at the tip of the knife to reduce the reservoir capacity from the liquid inlet to the liquid outlet. In addition, the position of the knife tip with respect to the backup roll is either horizontally oriented with respect to the backup roll, vertically installed at the top with respect to the backup roll, or vertically oriented with the backup roll below. I was there.

The liquid at the tip of the knife is not R-shaped, and the length from the liquid inlet to the liquid outlet is short, and the pressure at the tip of the knife in the liquid at the tip cannot be improved. As a result, the liquid at the liquid outlet The pressure was uneven. In addition, since the attachment position of the knife with respect to the backup roll does not have an angle in the advancing direction with respect to the lower vertical position of the backup roll, air may enter together with the base material from the liquid stop portion constituting the liquid pool at the tip of the knife. For this reason, it was difficult to apply both low and high viscosity liquids smoothly.

Problems to be solved by the invention

As described above, in a conventional knife coating apparatus using a backup roll, it is difficult to apply a high viscosity liquid to a low viscosity liquid from a thin film to a thick film without special adjustment without changing the knife itself. There was a problem that there was.

Means to solve the problem

In the present invention, a backup roll having a base material conveyance path formed on the outer peripheral surface, and a liquid supply part are formed in the transverse direction of the base material on the base material conveyance path, and the liquid supply part is directed from the liquid inlet to the outlet direction. In order to reduce the volume of the liquid reservoir, it has an R shape and the tip of the knife is provided at an angle of 15 to 45 degrees in the direction of travel of the substrate from vertically below the backup roll. Adjustment with which the gap between the backup roll and the knife tip can be adjusted toward the center of the backup roll. By providing a mechanism, coating liquids with low to high viscosity from 100mPa · s to 100,000mPa · s can be applied to the coating thickness from 5μm to several hundreds Without replacing the knife or the like to emissions meter, smooth can be applied only by adjusting the distance between the knife tip and the backup roll at an interval adjustment mechanism.

At this time, since the supply pressure that generates a constant flow rate varies depending on the viscosity of the coating liquid and changes to a certain value, it is necessary to apply a supply pressure corresponding to the coating liquid to the coating liquid.

In this way, it is possible to realize coating from a thin film to a thick film from a low viscosity coating liquid to a high viscosity coating liquid, which has been difficult in the past.

FIG. 1 shows an example of implementation in the knife coating apparatus of the present invention. In the present embodiment, the R shape of the knife tip is R62.5 mm.
In the present embodiment, a lever type adjusting mechanism is employed as a distance adjusting mechanism for the backup roll of the knife, but the distance adjusting mechanism is not limited to this.

In the coating example in the conventional backup roll type knife coating apparatus, when a coating liquid of 3,000 mPa · s is applied at a coating thickness of 20 μm, bubbles are formed in the coating by entrainment of air. There were many cases where coating defects such as contamination occurred.

Further, in one example, when a high speed operation exceeding 50 m / min is performed, the liquid pressure at the knife tip portion is not constant in the width direction, and coating defects such as unpainted portions and the surface are smeared.

In the examples according to the present invention, a coating liquid of 3,000 mPa · s could be applied smoothly from 5 micrometer to 200 micrometer without any coating defects. In addition, high speed coating up to 300 m / min at maximum was possible.

In addition, when a coating solution of 100,000 mPa · s is applied, in the conventional apparatus, the coating thickness cannot be made uniform in the width direction, and as a result, it is difficult to apply the coating liquid. However, in the examples of the present invention, it was possible to apply a coating solution of 100,000 mPa · s from 10 micrometer to 200 micrometer without any coating defects.

In another embodiment of the present invention, it was possible to apply an 800,000 mPa · s coating solution with a thickness of 100 microns.

The invention's effect

As described in the Examples, it was difficult to apply a high-viscosity coating liquid of 10,000 mPa · s in the conventional knife coating method using a backup roll. Moreover, it was difficult to coat with a thin film having a coating thickness of 20 micrometers or less. In addition, it was difficult to apply low-viscosity coating liquids of 1,000 mPa · s or less because the coating liquid pressure at the knife edge was insufficient.

However, in the knife coating apparatus according to the present invention, from a low viscosity coating solution of 100 mPa · s to a high viscosity coating solution of 10,000 mPa · s, a thin film having a coating thickness of 5 μm to a thick film having a thickness of 200 μm. Can be applied evenly at high speed.

It is an example of embodiment in the knife coating apparatus which concerns on this invention, and is a cross-sectional view which shows the relationship between a backup roller, a knife, and a space | interval adjustment mechanism. The tip of the knife is set at an angle of α degrees in the direction of movement of the base material from the lower vertical position of the backup roll. The distance adjustment mechanism that adjusts the distance between the knife and the backup roll moves the lever (5) up and down by the rotation of the eccentric cam (7). The lever is operated by a pneumatic cylinder for pressurization (6) and pivots around the fulcrum (8). Rotate in the direction, thereby adjusting the distance between the knife and the backup roll. 1 shows an example of an embodiment in a knife coating apparatus according to the present invention, and shows a state in which a knife is kept spaced from a base material on an outer periphery of a backup roll by a gap adjusting mechanism. Further, the coating liquid is pressurized and supplied from the coating liquid supply port (9), guided to the liquid reservoir at the tip of the knife, and pressurized by the effect of the knife R shape from the inlet to the tip of the liquid reservoir. It shows the state of being coated on the substrate from the tip of the knife. In this embodiment, the R shape of the knife tip liquid reservoir is R62.5, but the size of R is not limited to this.

Explanation of symbols

1. 1. Backup roll Base material 3. Coating knife4. 4. Coating liquid stopper member 5. Knife fixing and moving lever 6. Pneumatic cylinder for knife pressurization 7. Eccentric cam for interval adjustment mechanism Lever fulcrum 9 Coating liquid supply port 10. 10. Liquid reservoir portion for uniform coating liquid Knife tip liquid reservoir part A, knife tip liquid reservoir inlet part B, knife tip liquid reservoir outlet part

Claims (1)

A backup roll having a substrate conveyance path on the outer peripheral surface, and a liquid supply part is formed in the transverse direction of the substrate on the substrate conveyance path, and the liquid supply part is a liquid storage volume from the liquid inlet toward the outlet The tip of the knife, which is R-shaped and is the tip of the liquid outlet, is provided at an angle of 15 to 45 degrees in the direction of travel of the base material from the vertically lower side of the backup roll. There is a liquid stop portion provided in the transverse direction of the substrate with a small gap from the provided knife, and both the knife and the liquid stop portion can adjust the distance between the backup roll and the knife tip toward the center of the backup roll. A knife coating apparatus provided with an interval adjusting mechanism.

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