KR20180070572A - A method for winding a long substrate and a winding device, and a surface treatment device for a long substrate having the winding device - Google Patents

Abstract

The present invention proposes a method for winding a long substrate which is difficult to form a striped shape at both end portions of a wound long substrate. A method of winding a long substrate such as a long resin film, which is transported in a roll-to-roll state, onto a cylindrical winding core, is characterized in that when the long substrate (F) is wound around the winding core (26) And is wound so as to be farther from the center of rotation of the winding core than the center in the width direction, preferably 50 to 200 占 퐉 away from the leading end of the long substrate which is first wound in contact with the outer peripheral surface of the winding core.

Description

A method for winding a long substrate and a winding device, and a surface treatment device for a long substrate having the winding device

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a retracting method and a retracting device for retracting a long substrate to be transported in a roll-to-roll state onto a retracting core, and a surface treatment apparatus for a long substrate such as a roll-

2. Description of the Related Art A flexible wiring board having a wiring circuit on a resin film is used for a display panel such as a liquid crystal panel, a notebook computer, a digital camera, a cellular phone, and the like. Such a flexible wiring board can be produced by patterning a resin film with a metal film having a metal film on one side or both sides of the resin film. In recent years, the wiring pattern of the above-described flexible wiring board tends to become finer and denser, and accordingly, the resin film with a metal film is required to be smooth and free of wrinkles or streaks on the appearance.

As a method for producing the above-mentioned resin film with a metal film, a method of producing a resin film by adhering a metal foil to a resin film with an adhesive (a method of producing a three-layer substrate), a method of coating a resin solution on a metal foil, Casting method), a method of forming a metal film on a resin film by a vacuum film forming method alone, or a combination of a vacuum film forming method and a wet plating method (metalizing method). Examples of the vacuum deposition method used in the metallization method include a vacuum deposition method, a sputtering method, an ion plating method, and an ion beam sputtering method.

With respect to the metallizing method, for example, Patent Document 1 describes a method of sputtering a chromium layer on a polyimide insulating layer, followed by sputtering a copper layer to form a conductor layer. Such film formation by sputtering is generally excellent in adhesion, but is known to have a larger heat load applied to the resin film as a base material than in the vacuum evaporation method. It is also known that when a large heat load is applied to the resin film at the time of film formation, wrinkles easily occur in the film.

Therefore, in a process of forming a resin film such as a polyimide film by sputtering to produce a resin film with a metal film, a sputtering web coater equipped with a can roll is generally used. As described in Patent Document 2, this apparatus is a sputtering film forming apparatus which performs sputtering film formation while winding a long resin film which is rolled in a roll-to-roll manner on a can roll in which a refrigerant is circulated, The heat generated in the resin film can be immediately removed from the backside of the resin film. Therefore, it is possible to effectively suppress the occurrence of wrinkles by suppressing adverse effects of heat load during sputtering film formation.

However, in the conductive substrate used for the touch panel sensor of the display panel, it has been attempted to use a transparent resin film in which fine metal wiring is disposed instead of the conventional ITO electrode in order to increase the size and increase the response speed. Such a conductive substrate can also be made of a resin film with a metal film like the above-described flexible wiring substrate. However, when copper is used for a metal wiring, since copper has a metal luster, the problem that the visibility of the display is lowered due to reflection . Therefore, a black blackening layer may be formed on the surface of the metal wiring. For example, Patent Document 3 discloses a touch sensor panel having a blackening layer.

Japanese Unexamined Patent Application Publication No. 2-98994 Japanese Patent Application Laid-Open No. 62-247073 Japanese Patent Application Laid-Open No. 2013-225276

In the metalizing method described above, when a long substrate, which is transported in a roll-to-roll state under a reduced pressure atmosphere such as in a vacuum chamber, is wound around a cylindrical winding core, a striped shape is produced in both end portions in the width direction of the wound long substrate have. Particularly, in a resin film with a metal film on which a blackening layer containing an oxide of a metal which is chemically irregular in black is formed on the surface of the copper layer, the appearance of the stripes is bad and the product value is impaired. SUMMARY OF THE INVENTION It is an object of the present invention to propose a winding method and a winding device in which stripe-like shapes are hardly generated at both end portions in the width direction of a wound long substrate.

In order to achieve the above object, a method for winding a long substrate provided by the present invention is a method for winding a long substrate onto a cylindrical winding core, the long substrate being conveyed in a roll-to-roll state, , Both ends in the width direction of the elongated substrate are wound so as to be located farther from the center axis of rotation of the winding core than the center in the width direction.

In addition, the apparatus for winding a long substrate provided by the present invention is an apparatus for winding a long substrate onto a cylindrical winding core, the long substrate being conveyed in a roll-to-roll state, wherein both ends in the width direction of the long substrate, Are each formed with a convex stepped portion extending continuously in the circumferential direction.

According to the present invention, it is possible to substantially eliminate the occurrence of stripe-like shapes at both end portions in the width direction, which tend to occur when the surface-treated long substrate is wound around the winding core, so that the yield at the time of surface treatment of the long substrate can be increased .

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a front view showing one specific example of a vacuum film forming apparatus in which a winding device according to the present invention is suitably used. FIG.
Fig. 2 is a perspective view schematically showing a tensile force in the longitudinal direction generated when the long substrate is wound on the winding core. Fig.
3 is a perspective view showing a specific example of the winding device according to the present invention.
4 is a front view showing the winding device of the embodiment of the present invention.

First, referring to Fig. 1, as a specific example of a surface treatment apparatus to which the retracting apparatus for a long substrate of the present invention is suitably used, a film forming process in which a heat load is applied to a long substrate, which is transported in a roll- A vacuum deposition apparatus capable of performing vacuum deposition continuously and efficiently. In the following description, a long resin film substrate is used as an example of a long substrate and a sputtering film forming process is performed as an example of a film forming process in which a heat load is applied.

The vacuum film forming apparatus 10 of the elongated resin film substrate F shown in FIG. 1 (hereinafter, simply referred to as a long substrate F) is also called a sputtering web coater, The elongated substrate F wound from the core 14 is wound around the outer circumferential surface of the can roll 20 provided in the film forming chamber 12 and is subjected to film forming treatment by a sputtering mechanism as a surface treatment means to which a heat load is applied , And wound around a winding core (26) as a winding means provided in the winding chamber (13).

More specifically, in the roll-to-roll transport path of the elongated substrate F from the take-up core 14 to the take-up core 26, the elongated substrate F A tension sensor rolls 15 and 18 for measuring the tension of the elongated substrate F and a motor drive front feeder 15 disposed immediately upstream of the can roll 20, The rolls 19 are arranged in this order.

The front feed roll 19 plays a role of adjusting the speed of the elongated substrate F fed from the tension sensor roll 18 toward the can roll 20 with respect to the main speed of the can roll 20, As a result, the long substrate F continuously conveyed to the outer circumferential surface of the can roll 20 in which the coolant such as water is circulated can be surely brought into close contact with the inner circumferential surface of the can roll 20 and efficiently cooled.

The conveying path from the can roll 20 to the winding core 26 is also a motor for adjusting the main speed of the can roll 20 in the same manner as the conveying path from the winding core 14 to the can roll 20, The tension rollers 22 and 25 for measuring the tension of the elongated substrate F and the pre rolls 23 and 24 for guiding the elongated substrate F are arranged in this order Respectively.

In the take-up core 14 and the take-up core 26, the tension balance of the long substrate F is maintained by torque control by a powder clutch or the like, respectively. The elongated substrate F is pulled out from the winding core 14 by the forward feed roll 19 and the rear feed roll 21 which are driven by the motor and rotated by the rotation of the can roll 20, (Not shown).

The four long magnetron sputtering cathodes 30, 31, 32, and 33 are wound around the can roll 20 along a transport path defined on the outer circumferential surface of the can roll 20, As shown in Fig. Further, in the case of sputtering deposition of a metal film, a plate-shaped target can be used, but when a plate-shaped target is used, nodules (growth of foreign matter) may occur on the target. When this is a problem, it is preferable to use a cylindrical rotary target which is hard to generate nodules and has a high use efficiency of the target.

The vacuum film forming apparatus 10 is provided with a pre-roll (not shown) for changing the conveying direction of the long substrate F, a dry pump for maintaining the state of the vacuum chamber by depressurizing it, a turbo molecular pump, (Not shown) such as an o-coil is further provided. With this vacuum evacuation apparatus, the film forming chamber 12 of the vacuum film forming apparatus 10 is subjected to the pressure reduction up to the arrival pressure of about 10 ^-4 Pa and the pressure adjustment of about 0.1 to 10 Pa by the subsequent introduction of the sputtering gas, Sputtering film formation is performed under this pressure condition. A known gas such as argon is used for the sputtering gas, and a gas such as oxygen is further added depending on the purpose. The shape and material of the vacuum chamber are not particularly limited as long as they can withstand the above-described reduced pressure state, and various ones can be used.

By the metallizing method using the vacuum film forming apparatus 10 as described above, for example, a film of a Ni-based alloy or the like and a Cu film can be successively deposited on the surface of a long resin film by sputtering, Even when a large heat is applied to the elongated resin film by applying a large electric power, it is possible to immediately heat the film by the can roll 20, thereby enabling high-speed film formation. Therefore, it is possible to produce a high-quality resin film with a wrinkle-free metal film with high productivity, and it is possible to reduce the cost.

The film containing the Ni alloy or the like is called a seed layer and its composition is selected according to desired characteristics such as electrical insulation and migration resistance of the resin film with a metal film. Various known alloys such as Ni-Cr alloy, Inconel, Constantan and Monel can be used for the seed layer, and the thickness of the seed layer is generally 3 to 100 nm. When a metal film such as a Cu film laminated on the seed layer is to be made thicker by about 50 nm to 12 占 퐉, a general wet plating process may be performed as a post-process of the above vacuum film forming process. The wet plating process as the post-treatment may be made thick by a combination of a case of thickening the metal film only by the electroplating process and a combination of a plurality of wet plating methods having different plating conditions. In the latter case, for example, an electroless plating process is performed as the primary plating and an electrolytic plating process is performed as the secondary plating.

Further, an oxide film, a nitride film, or the like may be formed on the elongated resin film substrate in place of or in addition to the metal film such as Ni-Cr alloy or Cu. The kind and the film thickness of the oxide film or the nitride film are appropriately determined depending on the purpose, and also include films which are chemically irregular. The film thickness of these oxide films (including the case of chemically inferiority) or the nitride film (including the case of chemically inferiority) is generally in the range of 3 to 100 nm.

The resin film with a metal film formed by the above method is then patterned to a metal film by a subtractive method or a semi-additive method to form a wiring circuit. Here, the subtractive method is a method in which the surface of a resin film with a metal film is covered with a resist and an opening is formed by removing a resist other than a portion to be left as a wiring in a metal film (for example, the Cu film) And a metal film exposed from the opening is etched to form a wiring board.

On the other hand, the semi-additive method is a method in which a surface of a resin film with a metal film is covered with a resist, an opening in a portion of the metal film to be thickened is removed by removing the resist, A thick film wiring is formed by plating, a resist film is removed, and the whole is etched to remove the unnecessary portion of the metal film, thereby manufacturing a wiring substrate. Therefore, the film thickness of the metal film of the resin film with a metal film differs according to the manufacturing method of the above-described flexible wiring substrate. In general, the film thickness of the metal film when the subtractive method is employed is 5 to 12 μm, and the thickness of the metal film when the semi-additive method is employed is 5 μm or less.

Examples of the resin film used for the resin film with a metal film include a polyimide film, a polyamide film, a polyester film, a polytetrafluoroethylene film, a polyphenylene sulfide film, a polyethylene naphthalate film And a resin film such as a film or a liquid crystal polymerization system film. These materials are preferable because they have flexibility as a flexible substrate required for a resin film with a metal film, strength required for practical use, suitable electric insulation property as a wiring material, and the like. Further, the resin film having a thickness of 5 to 100 탆 and a width of 20 to 80 cm is preferable because it can be easily handled and can be satisfactorily subjected to the sputtering film forming process.

However, in the conductive substrate used as the member for the touch panel sensor, in order to prevent the reflection of the metal film such as the Cu film to be inconspicuous, a black blackening layer containing a metal oxide or the like chemically irregularly- . The blackening layer contains oxides of irregularity such as copper, nickel, tungsten and the like, and appears black in the naked eye. These chemically irregular films can be produced by suitably adding oxygen gas or nitrogen gas to the sputtering gas at the time of sputtering deposition.

However, when the blackening layer is formed on the surface of the metal film and then wound up by the winding core, stripes that can be visually recognized at both ends in the width direction of the wound resin film with the metal film may be formed. Particularly, when the thickness of a metal film (for example, a Cu film) on which a blackening layer is formed is 5 占 퐉 or less, stripes that can be visually recognized visually in the blackening layer may occur. It is presumed that the stripes are caused by the deterioration caused when the metal film is unevenly wound around both end portions and the central portion in the width direction when the elongated substrate is wound around the winding core. Of course, even if a blackening layer is not formed on the surface of a metal film (for example, a Cu film), the stripe can not be visually confirmed, but it is considered that the metal film is deteriorated due to unevenly tightening as described above .

The occurrence of the above-described striations becomes particularly conspicuous when the elongated substrate is wound under a reduced-pressure atmosphere. The reason is that, if the elongated substrate is wound around the winding core under atmospheric pressure, the atmosphere is mixed in between the wound elongated substrates, so that the tension in the longitudinal direction (conveying direction) Because it acts to mitigate. On the other hand, when the elongated substrate is wound around the winding core in a reduced-pressure atmosphere, the elongated substrate is tightened by the tensile force in the longitudinal direction at the time of winding described above because the gas is rarely mixed in between the wound elongated substrates. At this time, as shown by black arrows in Fig. 2, the distribution in the width direction of the elongated substrate F having the above tension is the strongest at the center in the width direction and weakest at both ends in the width direction.

Therefore, in one embodiment of the present invention, as shown in Fig. 3, convex portions 26 extending continuously in the circumferential direction are formed on the outer circumferential surface of the winding core 26 at positions where both end portions in the width direction of the elongated substrate F are wound, Thereby forming a step portion 26a of a shape. Thus, the tension in the longitudinal direction at both ends in the width direction of the elongated substrate F can be adjusted to be high, and the tension at the center in the width direction at the time of winding by the winding core 26 and the tension at both ends in the width direction are almost equal . As a result, deterioration of the elongated substrate F can be suppressed, and generation of stripe-like shapes at both ends in the width direction can be substantially eliminated.

That is, by forming the convex-shaped stepped portion 26a, the portion of the outer circumferential surface of the winding core 26, which is in contact with both end portions in the width direction of the elongated substrate F, The longitudinal ends of the elongated substrate F are wound so as to be positioned farther from the central axis O of the winding core 26 than to the center of the width direction. As a result, when the elongated substrate F is wound up following the rotation of the winding core 26, both ends in the width direction of the elongated substrate F are prevented from being displaced in the longitudinal direction by the convex shape step portions 26a So that the tensile force is applied in the longitudinal direction. This makes it possible to compensate for the tension in the longitudinal direction which is insufficient at both end portions in the width direction of the elongated substrate F, so that it is possible to prevent the partial tightening (bias of the tightening and winding) It is possible to prevent occurrence of streaks at both ends in the width direction.

The winding core 26 of the embodiment of the present invention preferably has an outer diameter of about 8 to 25 cm and is not particularly limited as long as it is longer than the width of the long substrate F to be wound. A pair of circumferentially continuous convex-shaped stepped portions 26a formed on portions of the outer circumferential surface of the winding core 26 that are in contact with both end portions in the width direction of the elongate substrate F are formed so as to have a step difference of 50 to 200 mu m . If the step difference exceeds 200 mu m, the adjacent layers of the elongated substrate F wound around the winding core 26 are easily charged by friction, and a discharge is generated due to a potential difference generated by charging, There is a possibility that a discharge trace may be generated. On the other hand, if the step is less than 50 탆, it is difficult to prevent the occurrence of streaks at the time of winding.

It is preferable that the length in which the elongated substrate F overlaps with the convex-shaped step 26a in the width direction thereof is 10 mm or less. For example, when a pair of convex-shaped stepped portions 26a enter between both corners of the long substrate F, it is preferable that each convex-shaped stepped portion 26a has a width of 10 mm or less. Each convex-shaped step 26a may be disposed only on the portion overlapping the elongated substrate F or may extend from the position overlapping the elongated substrate F to the rim of the winding core 26. [ Each of the convex-shaped stepped portions 26a may be provided with a belt-shaped resin film or a metal foil so as to generate a step on the flat outer circumferential surface of the winding core 26, or may be cut out from the cylindrical member so as to form a convex- .

Even if the convex shape step 26a is not formed in the winding core 26 as described above, the convex shape 26a is formed on the outer circumferential surface of the guide roll most adjacent to the winding core on the conveying path of the long substrate F The same effect can be obtained. In other words, even in the case of using the guide rolls having convex-shaped stepped portions on the outer peripheral surface, it is possible to increase the tension in the longitudinal direction at both end portions in the width direction of the elongated substrate F similarly to the case of the winding core 26 described above, Both end portions in the width direction of the elongated substrate F are liable to be charged because the elongate substrate F is wound around the outer peripheral surface of the elongated substrate F and contracts in the longitudinal direction at both end portions in the width direction of the elongated substrate F. As a result, It has been confirmed that there arises a problem that discharge occurs.

The winding core and the winding device having the winding core according to one embodiment of the present invention have been described above. However, the present invention is not limited to these specific embodiments, but may be practiced in various forms within the scope not departing from the gist of the present invention . For example, although the magnetron sputtering cathode is shown because the vacuum film forming apparatus 10 shown in Fig. 1 performs the sputtering film forming process as a process to which a heat load is applied, the process in which the heat load is applied is CVD ) Or other surface treatment such as vapor deposition treatment, another vacuum film forming means is provided instead of the plate-shaped target.

The present invention is not limited to a film forming apparatus for a long resin film under a reduced-pressure atmosphere. However, the present invention is also applicable to a drying apparatus using a heating heater at atmospheric pressure, Can be used. The long substrate used in this case may be a metal foil or a metal strip in addition to a resin film such as a polyethylene terephthalate (PET) film or a polyimide film.

Example

[Example 1]

A film-forming apparatus (sputtering web coater) shown in Fig. 1 was used, and a resin film with a metal film was produced by using oxygen gas as a reactive gas. Specifically, the surface of the roll body made of stainless steel having an outer diameter of 600 mm and a width of 750 mm having been hard chrome plated was used as the can roll 20, and the temperature was controlled at about 0 캜 by circulating the refrigerant therein. A Cu target for the metal layer was provided on the magnetron sputtering cathodes 30 and 31, and a Cu-Ni target for the blackening layer was provided on the magnetron sputtering cathodes 32 and 33.

A cylindrical member having an outer diameter of 180 mm and a length of 700 mm as shown in Fig. 4 was used as the winding core 26, and band-shaped resin films each having a thickness of 75 m and a width of 8 mm were attached to both ends thereof, A pair of convex-shaped stepped portions 26a of 75 mu m were formed. A PET film having a thickness of 50 m, a width of 600 mm and a length of 1200 m was used for the long substrate F. [ As a result, the overlapping of the convex-shaped step 26a in the width direction of the PET film became 8 mm.

The vacuum chamber 10 was evacuated to 5 Pa by a plurality of dry pumps, and further evacuated to 3 x 10 < ^-3 > Pa using a plurality of turbo molecular pumps and cryo-coils. The PET film was transported at a transporting speed of 2 m / min and film formation was carried out by electric power control so that a Cu film with a film thickness of 80 nm was obtained for the cathode 30 and the cathode 31. The film was formed on the cathode 32 and the cathode 33 A mixed gas of 500 sccm of argon gas and 50 sccm of oxygen gas was introduced and film formation was performed by power control so that a Ni-Cu oxide film having a chemically irregularity of 30 nm in thickness was obtained as a blackening layer. In this state, a PET film was formed to a thickness of 1200 m. When the resin film with a metal film wound around the winding core 26 after film formation was visually observed, no striations were observed at both ends thereof.

[Example 2]

A resin film with a thin metal film was produced in the same manner as in Example 1 except that the step difference of the convex-shaped step 26a was 180 mu m. After the PET film was formed to a thickness of 1200 m, the resin film with the metal film wound around the winding core 26 was visually observed, and no streaks were observed at both ends thereof.

[Comparative Example 1]

A resin film with a thin metal film was produced in the same manner as in Example 1 except that a flat wound core without the convex shape step 26a was used. After the PET film was formed to have a thickness of 1200 m, the resin film with the metal film wound around the winding core was visually observed, and streaks were formed at both ends.

[Reference Example]

Except that a guide roll was formed immediately upstream of the winding core 26 and a convex shaped step portion with a step of 75 占 퐉 was formed on both end portions of the outer circumferential surface of the winding core 26 so as to overlap with the PET film by 8 mm, A film was produced. When the PET film was formed to have a thickness of 1200 m and the resin film with a metal film wound around the winding core 26 was visually inspected, it was thought that the stripes were hardly formed at both ends, A discharge trace was generated.

F: Long substrate
O: rotation center axis
10: Vacuum deposition apparatus
11: Applying room
12: The Tent of Meeting
13: Winding room
14: Retracting core
16, 17, 23, 24: pre-roll
15, 18, 22, 25: tension sensor roll
19: forward feed roll
20: Can roll
21: rear feed roll
26: winding core
26a: step of convex shape
30, 31, 32, 33: Magnetron sputtering cathode

Claims (7)

A method of winding an elongated substrate on a roll-up roll, wherein the elongated substrate is wound on a cylindrical winding core, wherein when the elongated substrate is wound on the winding core, both ends of the elongated substrate in the width- Is wound so as to be located further away from the axis. The end of the elongated substrate which is first wound in contact with the outer circumferential surface of the winding core is wound such that both widthwise ends of the elongated substrate are located at a distance of 50 to 200 탆 from the center axis of rotation of the winding core Wherein the length of the elongated substrate is reduced. A winding apparatus for winding a long substrate on a cylindrical winding core, the long substrate being conveyed in a roll-to-roll state, wherein a convex shape continuously extending in a circumferential direction is formed in each of the circumferential surfaces of the long- And a step portion of the elongated substrate is formed. The apparatus according to claim 3, wherein the outer circumferential surface of the winding core has substantially the same outer diameter except for the convex stepped portion. The take-up device for a long substrate according to any one of claims 3 and 4, wherein the convex step has a step difference of 50 to 200 탆. There is provided a surface treatment apparatus for a long substrate having a surface treatment means for performing surface treatment on a long substrate conveyed in a roll-to-roll state in a vacuum chamber, and a winding means including a cylindrical core for winding a surface-
The apparatus for surface treatment of a long substrate as claimed in any one of claims 3 to 5, wherein the winding means is a winding device for a long substrate. A roll-to-roll sputtering apparatus characterized in that the surface treatment means according to claim 6 is a sputtering cathode.

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