JP2011174813A - Apparatus for manufacturing optical film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical film manufacturing apparatus, capable of achieving the continuous control of a dust amount over the whole region in the width direction of a film (web) at low cost. <P>SOLUTION: The optical film manufacturing apparatus 10 is composed of an unwinding part 12 for unwinding the web 14 from a raw web roll, a coating part 18 for coating the continuous running strip-like web 14 with a coating solution, and a winding part 22 for winding the web 14 provided with a coating layer as a winding roll. At least one dust measuring instrument 26 having the sampling nozzle 28a of a suction port having the flat shape corresponding to the width of the web is provided between the unwinding part 12 and the winding part 22. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an optical film manufacturing apparatus, and more particularly, to an optical film manufacturing apparatus for measuring dust on a web by providing a dust measuring device (particle counter).

  In a functional film (optical film) that forms various functions by forming a thin film on the web surface, minute dust causes defects, and therefore, dust management in the manufacturing process is important.

  In recent years, both the size and amount of dust in question have become increasingly demanding, and there is a need for more accurate measurement and management than ever before.

  A common method for measuring and managing airborne dust is to measure dust in a unit flow rate air introduced with a single suction tube using a light scattering particle counter. It is possible to know the spatial distribution of dust that changes every moment. The widths of optical films produced according to customer requirements are diversified and tend to increase, and it is impossible to perform sufficient quality control by pinpoint measurement as described above. In order to identify the cause (occurrence location) of the dust-induced failure that occurred during production, it is effective to constantly monitor the dust over the entire width of the product.

  As a method for knowing the planar dust distribution, a method is generally used in which a silicon wafer is left in a predetermined place for a certain period of time, and dust attached to the wafer is measured by a dedicated inspection apparatus. However, an expensive silicon wafer is used. The problem of cost and the problem of analysis that the time when each dust adheres to the wafer is not known in detail are pointed out, and various methods using a particle counter have been proposed.

In Patent Document 1 and Patent Document 2, a method is used in which a plurality of sampling tubes are connected to one particle counter and a measurement location is selected by a switching device of the sampling tubes.
In either case, it is possible to measure the amount of dust at a predetermined position in a wide area, but it is not possible to measure multiple locations at the same time. Not suitable for monitoring.

  Therefore, in order to solve the above-mentioned problem, Cited Document 3 makes it possible to connect a sampling tube and a particle counter to each of the suction ports continuously arranged in a predetermined area and continuously monitor the dust distribution. ing.

JP-A-7-209146 JP-A-2005-116854 JP 2001-264236 A

  However, there is no problem if the measurement object is a small size product such as a φ300 mm wafer as in the example of Cited Document 3, but the optical film described above has a width of several meters and a production line length of several hundred meters. There is a problem that it is large-scale and it is not practical in cost to manage these processes.

  The present invention has been made for such a problem, and provides an apparatus for manufacturing an optical film capable of realizing continuous dust amount management over the entire width direction of the film (web) at a low cost. It is an object.

  In order to achieve the above object, the present invention winds a web provided with an unwinding section for unwinding a web from a roll, a coating section for coating a coating liquid on a continuously running belt-shaped web, and a coating layer. In an optical film manufacturing apparatus comprising a winding unit that winds as a winding roll, a sampling nozzle having a flat suction port corresponding to at least one web width between the unwinding unit and the winding unit An apparatus for producing an optical film is provided, comprising a dust measuring device having

  Optical film manufacturing equipment is equipped with at least one dust measuring device that has a sampling nozzle with a flat suction port corresponding to the web width, enabling continuous management of the amount of dust across the entire width of the web at a low cost. can do.

  In the present invention, the width of the suction port of the sampling nozzle is preferably changed corresponding to the web width.

  Since the width of the optical film has various customer requirements, it is preferable that the width of the suction port of the sampling nozzle is changed in accordance with the web width.

  In the present invention, it is preferable that an area of the suction port of the sampling nozzle is constant even when the web width is changed.

  Even if the width of the suction port of the sampling nozzle changes, the suction air speed can always be kept at a predetermined value by making the suction area constant.

  Further, in the present invention, a plurality of sampling nozzles having different suction port widths corresponding to the web width are arranged adjacent to each other, and any one of the plurality of sampling nozzles is selectively used according to a change in the web width. Is preferred.

  A plurality of sampling nozzles having different suction port widths corresponding to the web width are arranged adjacent to each other, and an optimum one of the plurality of sampling nozzles is selected and used according to a change in the web width, so that the web widths are different. For a plurality of webs, continuous dust amount management over the entire web width direction can be realized.

  In the present invention, the sampling nozzle preferably has a shape in which the wind speed of the sampled gas is made uniform in the width direction.

  Since the sampling nozzle has a shape in which the wind speed of the sampled gas is made uniform in the width direction, the gas can be sampled at an equal specific gravity at all positions without depending on the position in the web width direction.

  In the optical film manufacturing apparatus of the present invention, it is preferable to include an inspection machine.

  The surface detector can detect only foreign matter of 10 μm or less, but there are some products that affect the optical performance when 0.1 μm foreign matter is attached to the optical film. In the present invention, the dust measuring apparatus is installed in each part of the manufacturing apparatus and always performs simultaneous measurement, so that the dust state of the order of 0.1 μm can be grasped for each part of the manufacturing apparatus. The measurement range is from the order of 0.1 μm to about 10 μm. Therefore, in the present invention, a quality defect position due to all dust generated on the web can be specified by further providing an inspection machine.

  In the present invention, it is preferable that a plurality of dust measuring devices and an inspection machine are provided, and the dust on the web is simultaneously measured by the plurality of dust measuring devices and the inspection machine.

  At the same time, by measuring the dust on the web, it is possible to accurately identify all the defective positions due to the dust generated on the web.

  In the present invention, at least one dust measuring device may be installed in an explosive gas environment. In this case, it is preferable that a gas concentration detector is installed in the explosive gas environment, and the dust measuring device has means for mixing an inert gas with the gas sampled for dust measurement.

  When a gas in an explosive gas environment is sampled, the dust measuring device may explode due to the explosive gas. Generally, a gas concentration detector has a gas detection time lag of several tens of seconds. Therefore, if the sampled gas is detected by the gas concentration detector, explosion cannot be prevented. Therefore, by installing a gas concentration detector in an explosive gas environment and mixing an inert gas with the gas sampled for dust measurement based on the detection result of the gas concentration detector in the explosive gas environment, The explosion of the dust measuring device due to a time lag of several tens of seconds can be prevented. Further, since the inert gas is mixed with the gas sampled for dust measurement based on the detection result of the gas concentration detector in the explosive gas environment, the running cost of the inert gas can be minimized.

  As described above, according to the optical film manufacturing apparatus of the present invention, it is possible to provide an optical film manufacturing apparatus capable of realizing continuous dust amount management over the entire web width direction at a low cost. . Further, according to the present invention, it becomes possible to accurately identify the position of poor quality due to dust generated on the web, and it is possible to drastically reduce the disposal of the places where there is a concern about dust adhesion, thereby improving the product yield.

The side view which shows typically the structure of the manufacturing apparatus of the optical film of this invention. The top view which shows the adjacent arrangement | positioning of a some sampling nozzle. The perspective view which shows the preferable shape of a sampling nozzle. The conceptual diagram which shows the preferable aspect of the dust measuring apparatus which concerns on this invention.

  Hereinafter, preferred embodiments of an optical film manufacturing apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

  First, an example of a configuration of an optical film manufacturing apparatus according to the present invention will be described. FIG. 1 shows a film 14 unwound from an original roll 12 that is continuously conveyed while being wound around rollers 16, 16... 1 shows an optical film manufacturing apparatus 10 that is dried by a drying unit 20 and wound up as a winding roll 22. When the coating liquid uses an ultraviolet curable resin, an ultraviolet irradiation unit (not shown) is provided downstream of the drying unit 20.

  The film 14 is a film-like material used, for example, for liquid crystal, optics, polarizing plates, etc., and is formed of TAC (triacetylene cellulose), PET (polyethylene terephthalate), or the like.

  As the coating unit 18, a dip coating method, an air knife coating method, a curtain coating method, a slide coating method, a roller coating method, a wire bar coating method, a gravure coating, a micro gravure method, or the like can also be used. The application unit 18 may be a clean atmosphere such as a clean room. At that time, the cleanliness is preferably class 1000 or less, more preferably class 100 or less, and still more preferably class 10 or less.

  A drying unit 20 is provided downstream of the application unit 18. In the drying part 20, the solvent of the formed coating film is evaporated and dried.

  In addition, the optical film manufacturing apparatus 10 includes a control panel 24 that controls the entire apparatus, and controls driving and stopping of the driving roller, operation of the coating unit, temperature adjustment of the drying unit, and the like.

  And in this invention, as shown in FIG. 1 and FIG. 2, the dust measuring device 26 which has the sampling nozzle of the flat suction port corresponding to at least 1 film width is provided. 1 and 2 show three sampling nozzles. Here, FIG. 2 is a view of the sampling nozzle as seen from above, and shows the positional relationship with the film.

  The sampling nozzles 28a, 28b, and 28c are connected to the switching valve 30 via pipes 32a, 32b, and 32c, respectively, and the switching valve 30 is connected to the dust measuring device 26 via the pipe 34.

  Here, as shown in FIGS. 1 and 2, when there are various production film widths, a plurality of sampling nozzles 28 a, 28 b, 28 c having different suction port widths corresponding to the film 14 width are arranged adjacently, Switching from the control panel 24 is performed by the switching valve 30 so as to select the optimum sampling nozzle 28a from the plurality of sampling nozzles 28a, 28b, 28c according to the change in width. In this way, by arranging a plurality of sampling nozzles having different inlet widths corresponding to the film width adjacent to each other, it is possible to continuously manage the amount of dust over the entire film width direction for a plurality of films having different film widths. Can be realized.

  Further, as shown in FIG. 2, it is preferable that the suction ports of the sampling nozzles 28a, 28b, and 28c have a constant area even when the film width is changed. Even if the width of the suction port of the sampling nozzle changes, the suction air speed can always be kept at a predetermined value by making the suction area constant. Therefore, it is possible to confirm the position of poor quality due to dust generated on the film with the standardized numerical value without being affected by the film width.

  The sampling nozzles 28a, 28b, and 28c preferably have a shape in which the wind speed of the sampled gas is made uniform in the width direction. FIG. 3 shows an example of the sampling nozzle, and a plurality of partition plates 31, 31... Are provided so that the ratio of the gas to be sucked does not change depending on the position of the suction port 29 in the width direction. Is.

  Since the sampling nozzle has a shape in which the wind speed of the sampled gas is made uniform in the width direction, the gas can be sampled by an equal amount at all positions without depending on the position in the web width direction. It is possible to accurately grasp the quality defect position (position in the length direction where the defect has occurred) due to the dust generated in.

  And in the optical film manufacturing apparatus 10 of this invention, it is preferable to provide the surface detector 40 with said dust measuring apparatus 26 (refer FIG. 1).

  The surface inspection machine is a device for detecting defects such as scratches and contamination on web sheets such as films, resin sheets, paper, coated products (coating), nonwoven fabrics, and metal sheets. The surface inspection machine is a combination of a CCD line sensor camera and a dedicated image processing device (not shown) that achieves both high-speed capture and high-speed data processing. Is recognized as a defect and processed by a computer. Here, as the surface inspection machine, for example, those manufactured by Takano Co., Ltd., Misuzu Erie Co., Ltd., or Toshiba Corp. can be preferably used.

  The surface detector can detect only foreign matter of a little less than 10 μm, but in the case of an optical film, if a 0.1 μm foreign matter adheres, the optical performance is affected. By providing the dust measuring device 26 according to the present invention at any position of the manufacturing apparatus 10 and performing the measurement, it becomes possible to grasp the dust state of the order of 0.1 μm for each part of the manufacturing apparatus. The measuring range of the apparatus is from the order of 0.1 μm to about 10 μm. Therefore, in the present invention, by further providing the surface inspection device 40, it is possible to identify a quality defect position due to dust of all sizes generated on the film.

  In the present invention, it is also preferable that the dust measuring devices 26 described above are provided at a plurality of sites, and the dust on the web is simultaneously measured by the plurality of dust measuring devices and a surface detector.

  In FIG. 1, for example, it is conceivable that a dust measuring device 26 according to the present invention is further provided in the application unit 18 and the drying unit 20. In the present invention, a dust measuring device is installed in each part of the manufacturing apparatus and always performs simultaneous measurement, so that all defective positions due to dust generated on the film can be accurately identified.

  That is, the dust measuring device 26 outputs to the control panel 24 the amount of dust in the vicinity of the film during the production of the optical film, and the control panel 24 matches the dust data with the defect detection data in the surface detector 40 to attach the dust. Identify the location.

  In addition, in FIG. 1, the dust measuring apparatus 26 which has the sampling nozzle of the flat suction port corresponding to the film width which concerns on this invention showed what was installed after the film roll 12 was unwound in FIG. However, it is also effective to provide the coating unit 18 and the drying unit 20. Moreover, the dust measuring device 26 having the sampling nozzle of the flat suction port corresponding to the film width according to the present invention is not limited to one, and it is preferable to provide a plurality of dust measuring devices in the optical film manufacturing apparatus 10.

  Here, when the dust measuring device 26 according to the present invention is provided in the coating unit 18 or the drying unit 20, if the coating liquid contains an organic solvent, the sampled gas is explosive and dangerous. In particular, if the explosive gas reaches the dust measuring device 26 as it is, the dust measuring device may explode due to the explosive gas.

  Incidentally, in general, a gas concentration detector has a gas detection time lag of several tens of seconds. Therefore, if the sampled gas is detected by the gas concentration detector, explosion cannot be prevented.

  Therefore, in the present invention, as shown in FIG. 4, the gas concentration detector 50a is installed in an explosive gas atmosphere separately from the gas concentration detector 50b, and the explosiveness sampled for dust measurement is provided. Based on the detection result of the gas concentration detector 50a in an explosive gas environment, the gas is mixed with an inert gas from the pipe 52 connected to the pipe 34, so that the explosion of the dust measuring device 26 due to a time lag of several tens of seconds can be prevented. It is preferable to prevent.

  In order to measure dust in the explosive gas atmosphere with the dust measuring device 26, specifically, dilution with an inert gas is performed only when the gas concentration of the gas concentration detector 50a exceeds a predetermined value A. When the predetermined value is exceeded, the flow rate of the inert gas is controlled using a gas flow meter and an automatic open / close valve (not shown). And both gas is mixed by forming a turbulent flow in the confluence | merging part of sampling gas and inert gas, and the dust amount in sampling gas is automatically converted from the flow rate ratio of sampling gas and inert gas. If the gas concentration of the gas concentration detector 50b exceeds the predetermined value B, the dust measurement is stopped. At that time, the laser emission of the dust measuring device 26 is stopped, and the suction of the sampling gas is stopped. The gas concentration detector 50a is preferably measured at a place where the gas concentration is highest in the explosive gas atmosphere.

  In this way, explosion of the dust measuring device 26 can be prevented, and an inert gas is mixed with the gas sampled for dust measurement based on the detection result of the gas concentration detector in the explosive gas atmosphere. By doing so, the running cost of the inert gas can be minimized.

  As described above, according to the optical film manufacturing apparatus of the present invention, by measuring dust using a sampling nozzle having a flat suction port corresponding to the manufacturing film width, continuous over the entire film width direction. The dust volume can be managed at low cost, and by using multiple sampling nozzles with a constant inlet area and different widths according to the width of the production film, the air velocity of the intake air is always maintained at a predetermined value. And stable dust measurement. Therefore, it is possible to continuously grasp the exact floating dust distribution over the entire width of the film, so it is possible to accurately link the dust-caused failure and the dust in the process, and quickly identify the cause of the failure, It is possible to detect failures early based on actual data.

  The optical film manufacturing apparatus according to the present invention can be preferably used for manufacturing an antireflection film and an optical compensation film that are required to have extremely strict appearance quality (no point defects, unevenness, dirt, etc.).

  As mentioned above, although the manufacturing apparatus of the optical film of this invention was demonstrated in detail, this invention is not limited to the said embodiment, You may perform various improvement and a change in the range which does not deviate from the summary of this invention. Of course.

 DESCRIPTION OF SYMBOLS 10 ... Optical film manufacturing apparatus, 12 ... Original fabric roll (unwinding part), 14 ... Film (web), 16 ... Roller, 18 ... Application | coating part, 20 ... Drying part, 22 ... Winding roll (winding part) , 24 ... Control panel, 26 ... Dust measuring device, 28a, 28b, 28c ... Sampling nozzle, 29 ... Suction port, 30 ... Switching valve, 31 ... Partition plate, 32a, 32b, 32c ... Piping, 34 ... Piping, 40 ... Surface detector, 50a, 50b ... gas concentration detector, 52 ... piping

Claims (9)

An unwinding section for unwinding the web from the raw roll, an application section for applying the coating liquid to the continuously running belt-like web, and a winding section for winding the web provided with the coating layer as a winding roll. In an optical film manufacturing apparatus,
An optical film manufacturing apparatus comprising: a dust measuring device having a flat suction port sampling nozzle corresponding to at least one web width between the unwinding portion and the winding portion.   2. The optical film manufacturing apparatus according to claim 1, wherein the width of the suction port of the sampling nozzle is changed in accordance with the web width.   The apparatus for producing an optical film according to claim 2, wherein an area of the suction port of the sampling nozzle is constant even when the web width is changed. A plurality of sampling nozzles with different inlet widths corresponding to the web width are arranged adjacently,
The apparatus for producing an optical film according to claim 3, wherein any one of the plurality of sampling nozzles is selectively used in accordance with a change in web width.   The said sampling nozzle is a shape in which the wind speed of the sampled gas is equalized in the width direction, The manufacturing apparatus of the optical film of any one of Claims 1-4 characterized by the above-mentioned.   The optical film manufacturing apparatus according to any one of claims 1 to 5, further comprising a surface inspection machine.   The optical film according to claim 6, further comprising a plurality of dust measuring devices and a surface detector, wherein dust on the web is simultaneously measured by the plurality of dust measuring devices and the surface detector. Manufacturing equipment.   The optical film manufacturing apparatus according to claim 1, wherein at least one dust measuring device is installed in an explosive gas environment.   9. The gas concentration detector is installed in the explosive gas environment, and the dust measuring device has means for mixing an inert gas with a gas sampled for dust measurement. An apparatus for producing an optical film described in 1.

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