JP2000279868A - Apparatus for preventing generation of bleeding in blade coating - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the subject apparatus not exerting adverse effect on rapid work in a coater part at a time of operation. SOLUTION: A coating apparatus is constituted so that a metering blade 3 is pressed to a web 2 continuously running on a backing roll in the width direction of the web to coat the web with a coating soln. In a bleeding preventing apparatus, a device 5 for supplying water or steam for suppressing the bleeding generated in the boundary region of the metering blade 3 and the web is provided to a coater head so as to be able to be housed in the lower portion of the coating apparatus corresponding to a situation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for preventing bleeding in blade coating. More specifically, the present invention relates to an apparatus for preventing bleeding from occurring in blade coating, which does not adversely affect quick work in a coater during operation.

[0002]

2. Description of the Related Art In general, a blade coater applies a coating liquid to a surface of a base paper which continuously travels via a backing roll from a coating liquid supply unit disposed opposite to the backing roll. A surplus of the coating liquid is scraped off with a metering blade to adjust the required coating amount.

However, when the coating speed is increased in order to improve the productivity, or when the concentration of the coating liquid is increased in order to shorten the drying process from the economical point of view, the tip portion of the metering blade may be reduced. It has long been known that a problem called bleeding occurs.

[0004] Although the theoretical considerations regarding bleeding have not been clarified, the phenomenon is that when the coating liquid is released from the metering blade at the outlet of the metering blade, the liquid circulates above the metering blade. It is a phenomenon that adheres to the tip and solidifies. The solidified coating liquid will be formed at the tip of the metering blade in the form of an icicle in the traveling direction of the web with the passage of time. In some cases, such a phenomenon can be seen.

[0005] The occurrence of bleeding adversely affects the operability of the coater and causes a fatal defect in the quality of coated paper. This is because the generated solids are separated from the metering blade, and especially when the solids are large, even if they come into contact with the base paper and damage the base paper surface to cause paper breakage or even if paper breakage does not occur. In the printing process, problems such as poor printing occur. If the solids are hard, the surface of the roll through which the web passes will be damaged in a later step of the coating process, and such a roll change is very costly.

[0006] Regarding the above-mentioned problems, it is possible to suppress the occurrence of bleeding to some extent by improving the base paper and the coating liquid, but it is difficult to completely prevent the occurrence of bleeding. Considering these, there are limits to how these methods can prevent bleeding. In recent years, the coating speed has been increasing more and more, and the occurrence of bleeding has emerged as a more important problem.

As means for suppressing the occurrence of such bleeding, for example, JP-A-4-22870
As described in "Apparatus and method for preventing occurrence of bumps in paper coating process" in Japanese Patent Publication No. 0, bleeding is remarkably increased by supplying water or steam to the tip portion of the metering blade. It is known to be improved, but when installing and fixing a device that supplies water or steam through a pipe, for example, in the width direction of the tip of the metering blade, workability becomes extremely difficult. You can easily imagine.

FIG. 3 is an enlarged view of the metering blade portion of the coater head 4 in FIG. 1 showing a perspective view of the bleeding prevention device according to the present invention. For example, an operational defect peculiar to blade coating is shown. When streaking occurs, it is necessary to perform an operation on the metalling blade 7 in order to remove foreign matter clogging between the web and the metalling blade, and when adjusting the profile, Also, since the blade pressure is adjusted by the knob 8 of the profiler installed on the coater head, the work at the metering blade is required. Furthermore, during operation, such work must be performed quickly, and for these reasons, in the width direction of the tip of the metering blade, a device for preventing the occurrence of bleeding such as a pipe as described above is installed, Obviously, when fixed, these operability becomes significantly more difficult.

[0009]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an apparatus for suppressing bleeding occurring at the tip of a metering blade, and to provide an apparatus for coating a blade which does not adversely affect quick operation at the metering blade. An object of the present invention is to provide a bleeding prevention device.

[0010]

The apparatus for preventing bleeding in blade coating according to the present invention applies a coating solution by pressing a metering blade 3 in the width direction of a web 2 continuously running on a backing roll 1. A blade coating device for supplying water or steam for suppressing bleeding generated in a boundary region between the metering blade 3 and the web 2, wherein a device 5 for supplying water or steam is provided at a lower portion of the coating device depending on the situation. Characterized in that it is attached to the coater head so that it can be stored in the coater head.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a bleeding prevention device in blade coating according to the present invention will be described based on a specific example shown in the accompanying drawings. In FIG. 1 showing a perspective view of a bleeding occurrence preventing device in the present invention, reference numeral 1 denotes a backing roll, and a web 2 passes on the backing roll 1 in the direction of an arrow. Reference numeral 3 denotes a metering blade, and reference numeral 4 denotes a coater head to which the metering blade is fixed. Such devices are common in the paper manufacturing industry and require no further explanation.

In the bleeding prevention device, since bleeding occurs in the boundary region between the metering blade and the web, it is necessary to supply water or steam to this portion in order to suppress the bleeding. . That is, the device 5 for supplying water or steam in FIG.
Is a bleeding occurrence prevention device in the present invention,
Water or steam is supplied uniformly in the width direction of the boundary region between the metering blade and the web. The bleeding prevention device is not particularly limited as long as it can supply water or steam uniformly in the width direction.

However, when the bleeding prevention device is fixed to the coater head as shown in FIG. 1, it is difficult to perform various operations at the time of operation including streak measures and profile adjustment as described above. It is clear that it will be.

For this reason, this apparatus is provided with rails indicated by 6 on both sides, and when work in the coater is required, the rail is automatically or manually moved to the lower part of the coating apparatus. It has a structure that can be stored. This 6
Are not particularly limited, as long as the bleeding prevention device of No. 5 can be promptly stored in the lower portion of the coating device without any problem. In addition, at the time of storage, as shown in FIG. 2 showing a perspective view when the bleeding occurrence prevention device of the present invention is moved to the lower portion of the coating device, a structure in which work on the coater portion, particularly the metering blade portion can be performed without any problem. It has become.

[0015]

According to the present invention, since the bleeding prevention device in blade coating can be freely stored in the lower portion of the coating device when necessary, work at the coater during operation is completely problematic. It can be seen that it can be done quickly without any problem.

[Brief description of the drawings]

FIG. 1 is a perspective view of a bleeding prevention device according to the present invention.

FIG. 2 is a perspective view when the bleeding prevention device according to the present invention is moved to a lower portion of a coater head.

FIG. 3 is an enlarged view of a metering blade portion of a conventional coater head.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 backing roll 2 web 3, 7 metering blade 4 coater head 5 device for supplying water or steam 6 rail 8 knob

Claims (1)

[Claims] 1. A blade coating apparatus for applying a coating liquid by pressing a metering blade 3 in a width direction of a web 2 continuously running on a backing roll 1, wherein the metering blade 3 and the A device 5 for supplying water or steam for suppressing bleeding generated in the boundary region of the web 2 is attached to the coater head so that the device 5 can be stored in the lower part of the coating device according to the situation. Characteristic bleeding prevention device in blade coating.