JPH0243157A - Dust removing method - Google Patents

Abstract

PURPOSE:To make minute dust sticking to the surface of a web removable irrespective of its thickness by setting a clearance between a backup roller and a blade for dust removal to such a size that is conformed to the dust to be removed. CONSTITUTION:Foreign substances sticking to the surface of a web 1 running in succession are removed by a blade 2. At this time, the web 1 is traveled as being pressed to a backup roll 3 in an interval between this backup roll 3 and the blade 2 extending along a rotating core direction of the backup roll 3, and a clearance 4 between the backup roll 3 and the blade 2 should be set to a distance conformed to size of foreign matter subject to removal. In consequence, the foreign matter is surely removable from the surface of the web 1 by the blade 2.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a dust removal method for removing foreign matter such as dust attached to the surface of a web (so-called flexible support such as paper or plastic). be.

[Conventional technology]

Conventionally, various dust removal methods have been used to remove foreign matter such as dust or stuck protrusions from the surface of a web, and in particular, to remove dust and the like from a running web. A method is proposed.

An example of a web to which the present invention is applied is a web whose width is 0.3 to 3 m and whose length is 45 to 10,000 m.
, polyethylene terephthalate, polyethylene-2,6-naphthalate, cellulose diacetate, cellulose triacetate, whose thickness is about 5 to 200 μm,
Plastic films such as cellulose acetate propionate, polyvinyl chloride, polyvinylidene chloride, polycarbonate, polyimide, and polyamide; paper; α-polyofrein having 2 to 10 carbon atoms such as polyethylene, polypropylene, and ethylene-butene copolymer; Flexible strips made of metal foils such as aluminum, copper, tin, etc., or strips with a preliminary processed layer formed on the surface using the strips as a base material. included.

Further, the web is coated with a coating liquid depending on its use, such as a photosensitive coating liquid, a magnetic coating liquid, a surface protection coating, an antistatic coating, or a slippery coating liquid, etc., and after drying, a desired width and a desired width are formed. It is cut into lengths, and typical products include various photographic films, photographic paper, and magnetic tape.

The above-mentioned dust removal method includes, for example, a method in which deposits on the surface of the web are captured by pressing a non-woven fabric or a brush held in an appropriate manner against the web (JP-A-61-136764, JP-A-61-136764). -2730
No. 90, Japanese Patent Application No. 6142741, No. 62-7329, No. 6294740, etc.), or by blowing clean air at high speed onto the web running on a backup roll to remove deposits from the surface of the web. There are methods of peeling the web and guiding it to a nearby suction port, and methods of directly polishing the web surface with a hard material such as diamond or sapphire (
JP-A-62-92130, JP-A No. 62-172532,
Dry dust removal methods such as those described in Japanese Patent Application No. 61-243553 and Japanese Patent Application No. 62-132991 are known.

In contrast to the dry dust removal method described above, there is a method in which the web is introduced into a cleaning liquid tank and the deposits are peeled off by ultrasonic vibration there, and a method in which the web is supplied with a cleaning liquid such as water or an organic solvent and then doctored or the like is used to remove the deposits. A method of removing foreign matter adhering to the surface by scraping it off together with the cleaning agent (Japanese Patent Laid-Open No. 5
Wet dust removal methods such as those described in Japanese Patent Application No. 9-150571, Japanese Patent Application Laid-open No. 62-60748, Japanese Patent Application No. 60-296826, etc.) are known.

[Problem to be solved by the invention]

The method of washing away dust requires water or an organic solvent as a cleaning agent, so a means for supplying the cleaning agent is required, which complicates the structure of the device and increases the cost of the organic solvent. Furthermore, since the web is once wetted, it is necessary to dry it as a subsequent process, and the web must be passed through a drying process.

Therefore, not only does the drying process require equipment and operating costs, but a predetermined path length is required between cleaning and, for example, applying a magnetic material to the web, and while traveling along this path length, Dust may re-adhere and interfere with the coating process.

In addition, since the cleaning agent is present on the web surface, even if a member such as a blade comes into contact with the web surface, the occurrence of scratches on the web surface is suppressed by the lubricating action of the cleaning agent, but on the contrary, it may stick strongly. There were drawbacks such as the inability to remove the dust that was present.

On the other hand, a dust removal method has also been disclosed in which compressed air is sprayed onto a web running on a roll with backup without using the above-mentioned cleaning agent, or static-eliminating ionized air is sprayed onto the web. However, although the method of blowing gas is effective in capturing relatively large deposits of several tens of microns or more, it is effective in capturing relatively large deposits of several tens of microns or more, but it cannot capture dust that is strongly attached to the web or large protrusions kneaded into the upper surface. Because the removal power was weak, dust removal (top cut) could not be performed, and the dust removal effect was not sufficient.

Therefore, in the dust removal method that directly scrapes the web surface without using gas or liquid, the web surface and, for example, an abrasive tape (or nonwoven fabric) are in physical contact, and with materials such as polyester base, scratches may occur. is easily formed.

In addition, there were problems in practicality, such as the web shavings generated by excessive rubbing and the fallen fibers of the nonwoven fabric being attached to the web again due to the effect of static electricity, causing new dust to adhere.

Furthermore, in the case of a dust removal method in which the web surface is directly rubbed with a sharp object, the web surface is directly polished with a hard material such as diamond or sapphire, which may cause scratches on the web due to physical contact and damage to the web surface. There is also
There were also problems in practicality, such as excess scraping caused by unnecessary excessive rubbing, which resulted in re-adhesion of the scraps to the web.

The present invention solves the above problems, and its purpose is to provide a dust removal method that removes dust, protrusions, etc. attached to the web surface without damaging the web surface.

Another object of the present invention is to remove dust from the web surface immediately before the next step, for example, immediately before the application part of magnetic material, etc., to reduce new dust adhesion in the post-dust removal step.

[Means to solve the problem]

The object of the present invention is to provide a dust removal method for removing foreign matter adhering to or sticking to the surface of a continuously running web, in which a backing roll and a blade extending along the rotation core direction of the backing roll are provided. The web is run while being pressed against the backing roll, a gap between the backing roll and the blade is set to a distance corresponding to the size of the foreign object to be removed, and the blade moves the foreign object away from the web. This can be achieved by a dust removal method characterized by removing dust from the surface of.

[Embodiment]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

Note that FIG. 1 is a schematic configuration diagram of an apparatus implementing the dust removal method of the present invention.

The web l is sent out from a delivery roll (not shown), and is run in the six directions of arrows at a predetermined tension and running speed by a run control means (not shown) so as to pass through a predetermined running route. The film is processed and wound onto a winding roll (not shown). The blade 2 provided on the travel path of the web I has an edge 2a that is at least wider than the web width along the web width direction, that is, the rotational axis direction of the backing roll 3,
The edge 2a faces the web surface and removes foreign matter such as dust and protrusions attached or fixed to the surface of the web 1.

Therefore, at the time when the web 1 passes through the gap 4, the back surface thereof runs in close contact with the outer and circumferential surface of the backup roller 3, the vertical fluctuation of the web 1 is suppressed, and the gap 4 is accurately This means that it is maintained at

What is important here is how the gap 4 is set.

The gap 4 is set to be larger than the thickness of the web 1, and its setting is determined by taking into consideration the thickness of the web 1 and the size of the dust to be removed. That is, by running the web 1 while pressing it against the backing roll 3 with appropriate tension between the backing roll 3 and the blade 1 extending along the rotation axis of the backing roll 3, the surface of the web is It is possible to position the web 1 and stably hold the web 1 from its back side, and furthermore, the backing roll 3 and the blade 2 can be
(To be precise, the edge of the blade) is set to a distance corresponding to the thickness of the web 1 plus the size of the foreign matter to be removed, so the edge 2a of the blade 2 The foreign matter can be removed from the surface of the web 1 without substantially contacting the surface of the web 1 and without causing unnecessary scratches.

To explain in more detail, the gap 4 formed between the edge 2a and the backup roller 3 is the gap between the web! Taking into account the variation in the thickness of the web 1, and detecting in advance the size of the dust attached to the web 1 and the fixed protrusions, the dust can be removed without the edge 2a substantially touching the web surface. The range is set by adjusting the position of the blade 2. By doing this, not only the occurrence of scratches but also the abrasions and the like that are newly generated when the edge 2a comes into contact with the web 1 are eliminated.

The blade 2 is preferably made of a hard material such as cemented carbide or ceramic, and the edge 2a preferably has a sharp blade shape. Further, the backing roll 3 is constructed with extremely high precision not only in its surface properties but also in its rotational performance.

In addition, if it is not necessary to remove small particles of dust adhering to the web 1, but instead large protrusions, etc., the position of the blade 2 is adjusted and the gap 4 is set to a large value. Dust of a desired size can be removed in accordance with subsequent processing steps.

The web 1 from which dust has been removed as described above is
It is guided to the application section IO via the roller 5.

The application section 10 has a configuration called a reverse roller type, and applies, for example, a magnetic liquid 14 to the surface of the web 1 from which dust has been removed by three rollers 11, 12, and 13. .

What should be noted in this configuration is that the structure of the dust removal part is extremely simple, consisting of the blade 2 and the backup roller 3, and therefore the dust removal part is located near the application part 10, in other words, just before the application part 10. It lies in the fact that it can be placed. According to such an arrangement, the distance that the web 1 from which dust has been removed reaches the application section 10 is shortened, and it is possible to reduce re-adhesion of dust during the running period.

Therefore, the magnetic liquid 1 is applied to the surface of the web l from which dust has been removed and free from undesirable scratches in the coating section 10.
4 is applied, the quality of the product is further improved.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above, and various modifications are possible.

For example, the foreign matter removed by the blade 2 may be sucked in by a suction means. Further, the rake angle of the blade 2 is not limited to a right angle as shown in FIG. 1, but can be changed as appropriate.

Further, regarding the application section 10, Japanese Patent Application Laid-Open No. 57-847
Publication No. 71, No. 5B-104666, No. 5B-109
It goes without saying that the coating method described in Japanese Patent Application No. 162 and Japanese Patent Application No. 59-94657, in which an extrusion type coating head is pressed against a web without backup to apply a magnetic liquid, for example, may also be applied.

〔Effect of the invention〕

As explained above, according to the dust removal method of the present invention, the gap between the backup roller and the dust removal blade is set to a size corresponding to the amount of dust to be removed. Regardless of the surface, fine dust adhering to the surface can be removed. Also,
If you want to set the gap to be relatively thick (for example, to remove dust larger than a predetermined size) relative to the thickness of the web,
By setting the gap in accordance with the thickness of the web and the size of the dust, desired dust removal can be performed without damaging the web surface.

Therefore, the dust removal method can remove dust and protrusions as necessary without damaging the web surface, and also does not damage the web surface and does not generate dust due to scratches.

Furthermore, by setting the backup roller and blade immediately before a coating device that coats the web with, for example, a magnetic material, the distance from the dust removal position to the coating position can be shortened, and the unnecessary shavings mentioned above can be reduced. In combination with prevention, re-deposition of dust can be reduced, and an inexpensive and efficient web dust removal method can be provided.

〔Example〕

The blade 2 was manufactured using cemented carbide, and the backup roller 3 was manufactured according to precision grade specifications.

The gap 4 was set variously as shown in Table 2, including the degree of deflection of the backup roller 3. The rake angle of the blade 2 was set, for example, to about 1 degree to 5 degrees.

The effectiveness was evaluated by removing dust using the dust removal method described in FIG. 1, and by detecting the trapping of foreign matter in the coating head 10 and the occurrence of streaks that occur when the web surface is scraped. .

The magnetic liquid is applied using a reverse roll type coating head 12 in the same manner as shown in FIG. (Epoxy equivalent: 500) was added to the mixture and uniformly mixed and dispersed.

Table 1 The web thickness was approximately 15 μm, the magnetic liquid coating length was 3000 m for each level, and the test results are shown in Table 2.

Without dust, many dust particles and protrusions were observed, clearly demonstrating the effect of the present invention.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing an embodiment of the dust removal method according to the present invention. 1...web, 2...blade, 3...
・Backup roller, 4... Gap, 5... Roller, 10... Coating device, 11.13...
Roller, 12... Application head, 14... Magnetic liquid, t
...Gap width. (3 other people) Table 2 As is clear from Table 2, when the gap width t is set to 50 μmm or less, dust and protrusions are completely removed, and there are almost no foreign matter traps in the coating head 12. , Moreover, no shavings occur on the surface of the web 1,
We were able to apply the magnetic liquid without any damage, so to speak. On the other hand, sample No. 6.7 to which the present invention is not applied. excision of
1 figure

Claims (1)

[Claims] In a dust removal method for removing foreign matter adhering or fixed to the surface of a continuously running web, the web is placed between a backing roll and a blade extending along the rotation core direction of the backing roll. The foreign matter is removed from the surface of the web by the blade, by running the web while pressing against the backing roll, and setting a distance between the backing roll and the blade corresponding to the size of the foreign matter to be removed. Dust removal method.