JP2018135542A - Method for treating surface of resin film and method for manufacturing copper-clad laminated substrate including the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for treating the surface of a resin film, capable of efficiently removing the fragile layer of the resin film.SOLUTION: A method for treating the surface of a resin film, performed before depositing a base metal layer and a copper coated layer comprises: contacting, for example, at least one surface of a resin film consisting of a long-sized resin-film F to the outer peripheral surface of a surface treatment roll 14: having an active unoxidized metal surface used as the outer peripheral surface; following the conveyance of the long-sized resin film F and rotating while preferably conveying the long-sized resin film in a housing 11 having a reduced pressure atmosphere with roll-to-roll; and having the outer peripheral surface preferably subjected to cleaning by a plasma irradiation or ion beam irradiation.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a resin film surface treatment method and a method for producing a copper-clad laminate having the surface treatment method.

  In electronic devices such as liquid crystal panels, notebook computers, digital cameras, and cellular phones, flexible wiring boards having wiring circuits formed on one or both sides of a heat-resistant resin film are used. This flexible wiring board can be produced by patterning the metal film of a resin film with a metal film obtained by coating a metal film on one or both surfaces of a heat-resistant resin film.

  As a manufacturing method of the resin film with a metal film, conventionally, a method of manufacturing a metal foil by attaching it to a resin film with an adhesive (manufacturing method of a three-layer substrate), a metal foil coated with a resin solution, and then dried. Manufacturing method (casting method), and a method of forming a metal film on a resin film by vacuum film forming method alone or in combination with vacuum film forming method and wet plating method (metalizing method), etc. Are known. Further, vacuum deposition methods, sputtering methods, ion plating methods, ion beam sputtering methods and the like are known as vacuum film forming methods employed in the metalizing method.

  For example, Patent Document 1 discloses a metallizing method in which a chromium layer is formed on a polyimide substrate by sputtering and then a copper layer is formed by sputtering to form a laminated conductor layer on the insulating layer. ing. Further, in Patent Document 2, a first metal thin film formed by sputtering film formation using a copper nickel alloy as a target and a second metal thin film formed by sputtering film formation using a copper target are arranged in this order on the polyimide film. A two-layer copper-clad laminate is disclosed. In order to continuously perform vacuum film formation on a long resin film, a sputtering web coater capable of performing dry plating on the surface of the long resin film (web) while being conveyed by roll-to-roll. Is generally used.

  By the way, although the resin film with a metal film obtained by the sputtering method among the above vacuum film forming methods is generally excellent in the adhesion between the resin film and the metal film, the resin film actually having the metal film formed thereon is used. When the peel strength was measured, it was often peeled inside the resin film by so-called cohesive peeling without peeling at the interface between the metal film and the resin film. The reason why such cohesive peeling occurs is considered to be that a weak layer called a fragile layer is generally present on the surface layer of the resin film, and peeling occurs from that point.

  Therefore, in the vacuum film formation method, it has been proposed to improve the peel strength by performing plasma treatment or ion beam treatment on the resin film as pretreatment. For example, in Patent Document 3, the effect of adhesion is defined by the thickness of the modified layer on the surface of the polyimide film modified by plasma treatment in a two-layer copper polyimide substrate composed of a polyimide film, a metal seed layer, and a copper layer. Technology is disclosed. Patent Document 4 discloses a technique for defining the effect of adhesion by the thickness of a metal mixed layer in a metal-coated polyimide resin substrate in which a barrier layer, a seed layer, and a conductive layer are formed after modification by a dry method. Has been.

Japanese Patent Laid-Open No. 2-98994 Japanese Patent No. 3447070 JP 2007-318177 A International Publication No. 2010/098236

  The surface treatment of the resin film by the plasma treatment and ion beam treatment described above effectively removes the fragile layer near the surface of the resin film and improves the adhesion by generating a functional group that develops adhesion. I am trying. However, since the thickness of the fragile layer can vary depending on the type and thickness of the resin film and the manufacturing method of the resin film, in order to improve the peel strength, for example, the processing conditions of the plasma treatment according to the type and thickness of the resin film It is necessary to adjust ion beam irradiation conditions, and it may be necessary to significantly change conditions such as processing speed in order to optimize the conditions.

  The present invention has been made paying attention to such conventional problems, and by efficiently removing a fragile layer that may cause variations in thickness and the like due to different types and manufacturing methods of the resin film, the resin It is an object of the present invention to provide a resin film surface treatment method capable of reducing variations in adhesion with a metal film formed on the film, and a copper clad laminated substrate manufacturing method using the surface treatment method. .

In order to achieve the above object, the present inventors formed a metal film by sputtering on the long resin film while being wound around the outer periphery of the can roll while cooling the long resin film conveyed by roll-to-roll. In this case, by bringing the surface of the long resin film into contact with a metal roller having an active surface state that is not oxidized before the film formation, the brittle layer of the long resin film is peeled off to form a metal roller. The inventors have found that it can be adhered, and have completed the present invention.

  That is, the resin film surface treatment method of the present invention is characterized in that at least one surface of the resin film is brought into contact with an unoxidized active metal surface.

  According to this invention, since the weak layer of a resin film can be removed, the adhesive force of this resin film and the metal film formed on the surface can be improved.

It is typical sectional drawing of the copper clad laminated board which can be produced with the manufacturing method of the copper clad laminated board of this invention. It is a typical front view of the surface treatment film-forming apparatus which can implement the surface treatment method of the resin film of this invention. FIG. 3 is a schematic front view of a roll-to-roll continuous electroplating apparatus preferably used when wet plating is performed after dry plating in the surface treatment film forming apparatus of FIG. 2.

  Hereinafter, a specific example of the resin film surface treatment method according to the present invention will be described by taking as an example the case of producing a copper-clad laminate for a flexible wiring board of a two-layer board by a metalizing method. As shown in FIG. 1, a copper-clad laminate generally has a base metal layer 2 and a copper layer 3 sequentially formed on at least one surface of a resin film 1 typified by a polyimide film without using an adhesive. It has a laminated structure laminated. The copper layer 3 may be composed of one layer, but in FIG. 1, it has a laminated structure of a copper thin film layer 3a and a copper electroplating layer 3b.

  The material of the resin film 1 is not limited to a polyimide film, and a polyamide film, a polyester film, a polytetrafluoroethylene film, a polyphenylene sulfide film, a polyethylene naphthalate film, a liquid crystal polymer film, or the like can be used. Among these materials, a polyimide film is preferable from the viewpoints of mechanical strength, heat resistance, and electrical insulation.

  The base metal layer 2 plays a role of improving the adhesion and heat resistance between the resin film 1 and the copper layer 3 and ensuring the reliability of the copper-clad laminate. The material is nickel, chromium, or these Of these, an alloy made of at least one of these is preferable, and among these, a nickel-chromium alloy is particularly preferable from the viewpoint of adhesion strength and ease of etching during patterning of a wiring circuit. The composition of the nickel-chromium alloy is preferably 15% by mass or more and 22% by mass or less from the viewpoint of improving corrosion resistance and migration resistance. Of these, nickel-chromium alloy (Ni-20Cr) with 20% by mass of chromium is distributed as a nichrome alloy and can be easily obtained as a sputtering target for the magnetron sputtering method. Alternatively, a base metal layer having a concentration gradient in the thickness direction may be formed by laminating a plurality of nickel-chromium alloy thin films having different chromium concentrations. Note that in the case of an alloy containing nickel, chromium, vanadium, titanium, molybdenum, cobalt, or the like may be added.

  The thickness of the resin film 1 is preferably 12.5 μm or more and 75 μm or less. The film thickness of the base metal layer 2 is desirably 3 nm or more and 50 nm or less. When the film thickness of the base metal layer 2 is less than 3 nm, it becomes difficult to stably maintain the adhesion with the copper layer 3 when the resin film 1 is a polyimide film, and the corrosion resistance and migration resistance become insufficient. There is a fear. On the other hand, if the thickness of the base metal layer 2 exceeds 50 nm, it becomes difficult to sufficiently remove the base metal layer 2 when processing the wiring circuit by the subtractive method, and problems such as migration between adjacent wirings occur. There is a fear. The thickness of the copper layer 3 is preferably 100 nm or more and 20 μm or less, and the upper limit thereof is more preferably 12 μm or less. When the copper layer 3 has a two-layer structure as shown in FIG. 1, it is preferable that the film thickness of the copper thin film layer 3a is 10 nm or more and 1 μm or less, and the remaining film thickness is the copper electroplating layer 3b.

  Next, the above-described method for producing a copper clad laminated substrate will be described by taking, as an example, the case in which film formation by dry plating and film formation by wet plating are performed in this order after the surface treatment is performed on the resin film. . First, the surface treatment film forming apparatus 10 shown in FIG. 2 will be described. This surface treatment film forming apparatus 10 performs pretreatment on the surface of a long resin film F conveyed by roll-to-roll, and subsequently forms a film by dry plating on the pretreated surface. It is.

More specifically, the surface treatment film forming apparatus 10 includes various roll groups that define a transport path of the long resin film F that is transported by roll-to-roll, and before the pretreatment is performed on the long resin film F. Mainly composed of a processing means and a film forming means for forming a film on the pre-treated long resin film F. These are various vacuum devices such as a dry pump, a turbo molecular pump, and a cryocoil (not shown). Is housed in a housing 11 having The shape of the housing 11 is not limited to the rectangular parallelepiped shape of FIG. 2 as long as it can withstand a reduced internal atmosphere of about 10 ^{−4 to 1} Pa, and may be a cylindrical shape or the like.

  The above-mentioned various roll groups are the unrolling roll 12 from which the long resin film F is unwound, and the surface treatment roll as the first pretreatment means for performing the first surface treatment on the unrolled long resin film F. 14, a nip roll 15 for sandwiching the long resin film F with the outer peripheral surface of the surface treatment roll 14, and a heat load applied to the long resin film F after the first pretreatment by a second pretreatment means The first can roll 18 is cooled when the second pretreatment is performed, and the long resin film F after the two pretreatments is cooled when the sputtering film formation is applied with a thermal load. The second can roll 21, the front feed roll 20a and the rear feed roll 20b positioned immediately upstream and downstream of the second can roll 21, respectively, and the long resin film formed by sputtering. Winding roll 23 is capable of winding a beam F, and consists of a guide roll 13a~13n provided appropriately between the rolls. The interior of the housing 11 is partitioned by a partition into five spaces, an unwinding zone, a first pretreatment zone, a second pretreatment zone, a sputtering film formation zone, and a winding zone. Each of the roll groups is arranged in the space.

  A surface treatment sputtering cathode 16 is provided at a position facing an outer peripheral surface located within an angle range that does not come into contact with the long resin film F in the entire angle range around the rotation axis of the surface treatment roll 14. Yes. By this surface treatment sputtering cathode 16, an active metal film (hereinafter also referred to as an unoxidized active metal film) that is not oxidized can be formed on the outer peripheral surface of the surface treatment roll 14. That is, in the outer peripheral surface of the surface treatment roll 14, an unoxidized active metal surface is formed by sputtering when the region that contacts the long resin film F comes to a position that does not contact the long resin film F by rotation. It is like that. The metal used as the material of the unoxidized active metal film is preferably copper, nickel, chromium, titanium, or any alloy thereof. In particular, nickel, chromium, or titanium is preferable because organic substances are easily bonded by coordination or the like.

  The thickness of the unoxidized active metal film formed on the outer peripheral surface of the surface treatment roll 14 by the surface treatment sputtering cathode 16 is preferably 1 nm or more and 10 nm or less. If the thickness of this metal film is less than 1 nm, it is too thin to form the unoxidized active metal film almost uniformly. On the other hand, even if the thickness of the metal film exceeds 10 nm, the effect is hardly improved further. The thickness of the unoxidized active metal film can be estimated from the film formation efficiency of the sputtering cathode 16. The film formation efficiency of the sputtering cathode 16 can be known by forming an unoxidized active metal film on a resin film using the sputtering cathode 16 and measuring the thickness of the unoxidized active metal film formed on the resin film. it can. From the film formation efficiency of the sputtering cathode 16, the thickness of the unoxidized active metal film may be controlled by the input power to the sputtering cathode 16.

  Of the entire angle range around the rotation axis of the surface treatment roll 14, the surface treatment sputtering cathode 16 is disposed at a position facing the outer peripheral surface located within the angle range not in contact with the long resin film F. In addition, it is desirable to provide a processing means for cleaning the outer peripheral surface. In the surface treatment film forming apparatus 10 of FIG. 2, the cleaning treatment means 17 for cleaning the outer peripheral surface of the surface treatment roll 14 is a position facing the outer peripheral surface and the rotation direction of the surface treatment roll 14 is the above. It is provided in front of the surface treatment sputtering cathode 16. Thereby, the area | region which contacts the elongate resin film F in the outer peripheral surface of the surface treatment roll 14 is the position which contacts the elongate resin film F by rotation, and the non-oxidized active metal by said sputtering cathode 16 for surface treatment. When it comes to the position where the surface is formed, a cleaning process is performed

  By providing the cleaning processing means 17, the fragile layer from the long resin film F transferred to the surface of the non-oxidized active metal film on the outer peripheral surface of the surface treatment roll 14 can be removed. That is, the outer peripheral surface of the surface treatment roll 14 is weakened from the surface treatment roll 14 due to rotation by (1) deposition of an unoxidized active metal film by sputtering and (2) contact with the long resin film F. The surface treatment cycle consisting of layer transfer and (3) removal of the fragile layer by cleaning treatment is repeated.

  The cleaning processing means 17 is preferably one using plasma irradiation or ion beam irradiation. The output of plasma irradiation or ion beam irradiation may be any output that can satisfactorily remove the fragile layer from the long resin film F transferred to the surface of the non-oxidized active metal film on the outer peripheral surface of the surface treatment roll 14. In the surface treatment film forming apparatus 10 shown in FIG. 2, a cleaning ion source for irradiating an ion beam is provided as the cleaning processing means 17.

  In the case where the atmosphere of this cleaning process and the sputtering film forming process on the long resin film F to be described later can be shared, an ion beam process or a plasma process using argon gas is preferable, and in terms of gas pressure control. An ion beam is more preferable. On the other hand, in the case of an equipment in which the atmosphere of the sputtering film forming process and the cleaning process on the long resin film F can be controlled independently, the cleaning process is performed using argon having a gas pressure different from that of the sputtering film forming process. It is preferable to use plasma in a gas atmosphere, an atmosphere mainly containing oxygen gas or nitrogen gas, an atmosphere partially containing argon gas, or a mixed gas atmosphere thereof. Among these, plasma in an atmosphere containing oxygen gas as a main component is most suitable for removing the fragile layer. The gas pressure of the atmospheric gas is preferably 0.6 to 2.5 Pa, and the applied voltage of plasma is preferably 800 to 2600V.

  The long resin film F in contact with the outer peripheral surface of the surface treatment roll 14 is desirably sandwiched between the outer peripheral surface of the surface treatment roll 14 using the nip roll 15 as described above. Thus, by sandwiching the long resin film F between the surface treatment roll 14 and the nip roll 15, one side of the long resin film F can be reliably brought into contact with the surface of the unoxidized active metal film of the surface treatment roll 14. it can. The pressure when the long resin film F is sandwiched between the nip roll 15 and the surface treatment roll 14 is preferably 30 N or more and 180 N or less, more preferably 30 N or more and 150 N or less, and further preferably 30 N or more and 120 N or less. If this pressure is less than 30 N, the long resin film F may not contact the surface treatment roll 14 reliably. Conversely, when it exceeds 180 N, it becomes difficult to control the transport tension of the long resin film F.

Instead of the nip roll 15, the transport tension of the long resin film F may be adjusted to a predetermined value, and the long resin film F may be partially wound around the outer peripheral surface of the surface treatment roll 14. In this case, the long resin film F is reliably applied to the surface of the unoxidized active metal film of the surface treatment roll 14 by the drag of the following formula 1 generated between the long resin film F and the outer peripheral surface of the surface treatment roll 14. The surface treatment of the long resin film F can be performed stably as in the case of the nip roll 15.
[Formula 1]
Drag = transport tension of long resin film / (radius of surface treatment roll x width of long resin film)

  Also in this case, the conveyance tension of the long resin film F and the radius of the surface treatment roll 14 are appropriately selected so that the drag generated between the long resin film F and the outer peripheral surface of the surface treatment roll 14 is 30 to 180 N. do it. However, since the drag which the long resin film F receives from the outer peripheral surface of the surface treatment roll 14 changes according to the angular position of the circumferential direction, the conveyance tension of the long resin film F and the long resin film in the surface treatment roll 14 are changed. It is preferable to appropriately adjust the holding angle of F (that is, the angle range in which the long resin film F is wound around the entire outer peripheral surface of the surface treatment roll 14). Further, when the thickness of the long resin film F is reduced, wrinkles (trough wrinkle) may be generated or broken due to an increase in tension. Therefore, the long resin film F is formed on the outer peripheral surface of the surface treatment roll 14. In addition to adjusting the drag by winding, it is preferable to use the nip roll 15 described above in combination.

  The long resin film F from which the fragile layer has been removed by contact with the unoxidized active metal is preferably further subjected to surface treatment by plasma treatment or ion beam treatment. When the surface of the long resin film F from which the fragile layer has been removed is irradiated with plasma or an ion beam, functional groups such as carboxyl groups can be introduced into the molecules constituting the long resin film F. The adhesion between the film F and the base metal layer formed on the surface of the film F can be further improved.

  However, when plasma treatment or ion beam treatment is performed on the long resin film F, the temperature of the long resin film F rises, so that temperature adjustment is necessary. In the surface treatment film forming apparatus 10, the entire angle range around the rotation axis of the first can roll 18 so that the ion beam treatment is performed when the long resin film F is wound around the outer peripheral surface of the first can roll 18. Among these, for the surface treatment for irradiating the ion beam toward the surface of the long resin film F on the outer peripheral surface at a position facing the outer peripheral surface located within the angular range around which the long resin film F is wound An ion source 19 is provided. And the refrigerant | coolant supplied from the exterior of the housing | casing 11 circulates through the flow path provided in the inside of the 1st can roll 18. As shown in FIG.

  It is desirable that the long resin film F subjected to the first and second surface treatments as described above is subsequently subjected to film formation treatment of the base metal and the copper thin film layer by dry plating in the same apparatus. By subjecting the long resin film F to continuous surface treatment and film formation in the same apparatus, the surface-treated long resin film F is hardly contaminated and a base metal layer is formed on the surface thereof. This is because a film can be formed. Examples of the dry plating method for forming the base metal layer and the copper thin film layer on the long resin film F include a sputtering method, an ion plating method, a cluster ion beam method, a vacuum deposition method, and a CVD method. From the viewpoint of controlling the composition of the underlying metal layer as the seed layer, the sputtering method is desirable.

  When forming a film on the long resin film F by a sputtering method, a known sputtering film forming means can be used, for example, a general roll-to-roll sputtering apparatus (sputtering web coater) can be used. By using a roll-to-roll sputtering apparatus, it is possible to produce a polyimide film with a copper thin film layer by continuously and efficiently forming a base metal layer and a copper thin film layer on the surface of a long resin film made of a polyimide film or the like. it can.

  The surface treatment film forming apparatus 10 in FIG. 2 is a roll-to-roll sputtering apparatus so that such continuous sputtering film formation is possible. That is, the long resin film F transported by roll-to-roll along the transport path defined by the various roll groups described above from the unwinding roll 12 to the winding roll 23 in the housing 11 is replaced with the second can roll 21. Sputtering film formation is performed by the sputtering film forming means described later while being wound around the outer peripheral surface of the film and cooling.

  Of the roll group, the second can roll 21, the front feed roll 20a located immediately upstream thereof, the unwinding roll 12 and the winding roll 23 are provided with a power source by a servo motor, The other rolls are free rolls. Further, the unwinding roll 12 and the winding roll 23 are configured such that the tension balance of the long resin film F is maintained by torque control using a powder clutch or the like. The guide rolls 13j and 13k are provided with a tension sensor for measuring the tension of the long resin film F being conveyed.

  The outer peripheral surface of the second can roll 21 is finished with hard chrome plating, and a refrigerant circulation path as a cooling mechanism is provided therein. The outer peripheral surface of the second can roll 21 can be adjusted to a constant temperature by circulating the refrigerant and the heating medium supplied from the outside of the housing 11 through the refrigerant circulation path. With the above configuration, the long resin film F can be securely adhered to the outer peripheral surface of the second can roll 21, so that the long resin film F is subjected to sputtering film formation with a thermal load by the film forming means described later. However, wrinkles or the like hardly occur in the long resin film F.

  For example, magnetron cathode type sputtering cathodes 22 a, 22 b, 22 c, and 22 d as sputtering film forming means are arranged in this order along the transport path of the long resin film F at a position facing the outer peripheral surface of the second can roll 21. It is provided so that the surface of the long resin film F can be subjected to a sputtering film forming process which is a dry film forming process in which a thermal load is applied. In addition, in sputtering cathode 22a-22d, it is preferable that the length extended in the width direction of the long resin film F is wider than the width of the long resin film F.

  When the base metal layer and the copper thin film layer are formed after pre-processing on the surface of the long resin film F using the surface treatment film forming apparatus 10 described above, a target having the composition of the base metal layer is, for example, a sputtering cathode. At the same time, the copper target is attached to the remaining sputtering cathodes 22b to 22d. Further, for example, a long polyimide film is set on the unwinding roll 12 as the long resin film F, and the refrigerant is circulated through the first and second can rolls 18 and 21. And after evacuating the inside of the housing | casing 11, sputtering gas, such as argon, is introduce | transduced and atmospheric pressure is hold | maintained at about 1.3 Pa. In this state, while feeding a long polyimide film on a roll-to-roll basis, power is supplied to the above-described surface treatment sputtering cathode 16, cleaning treatment means 17, and sputtering cathodes 22a to 22d. Thereby, the polyimide film F2 with a copper thin film layer excellent in adhesion can be produced. Note that the copper thin film layer may be formed by vapor deposition after the base metal layer is formed by sputtering.

  Next, a copper electroplating layer is formed by electroplating on the polyimide film F2 with the copper thin film layer on which the base metal layer and the copper thin film layer are formed by the surface treatment film forming apparatus 10. The film thickness of the copper electroplating layer to be formed is preferably 1 μm or more and 20 μm or less. As the electroplating method, for example, a method of performing electroplating using an insoluble anode in a copper plating bath containing copper sulfate can be used. The composition of the copper plating bath is not particularly limited, and a commonly used high-throw copper sulfate plating bath for printed wiring boards can be used.

  FIG. 3 shows a roll-to-roll continuous electroplating apparatus (hereinafter also referred to as a plating apparatus 30) as a specific example of a plating apparatus capable of forming a copper plating film by the above electroplating method. This plating apparatus 30 is a copper film having a predetermined thickness by repeatedly immersing the polyimide film F2 with a copper thin film layer continuously unwound from the unwinding roll 32 into the plating solution in the electroplating tank 31. The electroplating layer is formed by electroplating. After electroplating, it is wound up on a winding roll 36 as a copper-clad laminated substrate S which is a metallized resin film substrate for a two-layer flexible wiring board.

  More specifically, the polyimide thin film F2 with a copper thin film layer, which has been unwound from the unwinding roll 32, preferably at a conveyance speed within a range of several m to several tens of m / min, travels downward by the feeding roll 33a. Is changed, and then introduced into the plating solution stored in the electroplating tank 31. The polyimide film F2 with a copper thin film layer that travels downward in the plating solution travels upward in the plating solution after the traveling direction is reversed by the reversing roll 35a, and is pulled up onto the surface of the plating solution by the power supply roll 33b It is done.

  Insoluble anodes 34a and 34b are provided at positions facing the polyimide film F2 traveling downward and the polyimide film F2 traveling upward, respectively. A power source (not shown) is connected between the power supply roll 33a and the insoluble anodes 34a and 34b. A plating circuit is configured.

  With the above configuration, a plating layer is formed on the surface of the copper thin film only while being immersed in the plating solution. By repeating this immersion in the plating solution a predetermined number of times (four times in FIG. 3), A copper electroplating layer having a desired film thickness can be formed on the metal thin film of the polyimide film F2 with a copper thin film layer. Thereby, the copper clad laminated substrate S for two-layer flexible wiring boards can be produced. As the insoluble anode, a known anode whose surface is coated with a conductive ceramic can be used. A mechanism for supplying copper ions to the plating solution is provided outside the electroplating tank 31. Copper ions can be supplied to the plating solution using an aqueous copper oxide solution, an aqueous copper hydroxide solution, an aqueous copper carbonate solution or the like, or a small amount of iron ions is added to the plating solution to dissolve the oxygen-free copper ball. The method may be used.

[Example 1]
After performing surface treatment on Kapton 150ENC (film width 500 mm) having a film thickness of 38 μm made of Toray DuPont polyimide as a long resin film F using a surface treatment film forming apparatus 10 as shown in FIG. Sputtering film formation was performed. For this surface treatment, a Cu—Ni alloy film having a thickness of 10 mm (1 nm) was formed on the outer peripheral surface of the surface treatment roll 14 having a radius of 20 cm by the surface treatment sputtering cathode 16.

  The cleaning process of the outer peripheral surface of the surface treatment roll 14 was performed by irradiating the argon ion beam with a flow rate of 100 sccm and 2000 V by the cleaning processing means 17. As a result, the outer peripheral surface of the surface treatment roll 14 is rotated by (1) film formation of an unoxidized and active metal film, (2) contact with the long resin film F, and (3) cleaning treatment. The surface treatment cycle consisting of was repeated. In addition, since the conveyance tension of the long resin film F was set to 100 N in the upstream and downstream of the surface treatment roll 14, the drag generated between the long resin film F and the surface treatment roll 14 was 1000 N.

  After the surface treatment, a Ni-20Cr alloy film with a thickness of 5 nm was formed by sputtering without performing treatment with the ion source 19 for surface treatment, and a copper thin film layer with a film thickness of 100 nm was further formed on the surface by sputtering. Thus, with respect to the film-forming surface of the long resin film F formed by dry plating, the film thickness of the copper layer is 8 μm using a roll-to-roll continuous electroplating apparatus 30 as shown in FIG. Copper was electroplated with an aqueous copper sulfate solution having a pH of 1. In this way, a copper clad laminated substrate was produced.

  In addition, as the long resin film F, a 10 μm-thick polypropylene film made by Shin-Etsu Film, Shine SRF with a 80 μm thickness made of PET made by Toyobo Cosmo, and a 50 μm-thick Vector star made of Kuraray LCP (liquid crystal polymer) A copper-clad laminate was prepared in the same manner as described above (both having a film width of 500 mm). Further, for Kapton 150ENC manufactured by Toray DuPont, a copper-clad laminate was prepared in the same manner as described above except that a Cu film having a thickness of 10 mm was formed instead of the Cu-Ni alloy.

[Example 2]
Five types were performed in the same manner as in Example 1 except that the long resin film F surface-treated with the surface treatment roll 14 was further surface-treated with an argon ion beam having a flow rate of 100 sccm and 2000 V by the surface treatment ion source 19. A copper-clad laminate was prepared.

[Comparative example]
Five types of copper-clad laminated substrates were produced in the same manner as in Example 1 except that the surface treatment with the surface treatment roll 14 was not performed.

[Evaluation]
For each of the copper clad laminated substrates obtained in Examples 1 and 2 and the comparative example, the metal film was etched so that a line-shaped circuit pattern having a line width of 1 mm was formed on the metal film, and the room temperature The adhesion strength (peel strength) was measured according to IPC-TM-650, Number: 2.4.9, Revision: E, Method: A. The measurement results are shown in Table 1 below.

  As can be seen from Table 1 above, the copper-clad laminates of Examples 1 and 2 produced by applying the resin film surface treatment method of the present invention were the comparative example copper produced without applying the surface treatment method. Compared to the tension laminate, high adhesion was obtained regardless of the type and thickness of the resin film. Further, in Example 2 in which the treatment with the argon ion beam was performed after the surface treatment with the surface treatment roll, higher adhesion was obtained than in Example 1 in which the treatment with the argon ion beam was not performed.

DESCRIPTION OF SYMBOLS F Long resin film F2 Polyimide film with a copper thin film layer S Copper-clad laminated board for 2 layers flexible wiring boards 1 Polyimide film 2 Base metal layer 3 Copper layer 3a Copper thin film layer 3b Copper electroplating layer 10 Surface treatment film-forming apparatus 11 Case 12 Unwinding roll 13a-13n Guide roll 14 Surface treatment roll 15 Nip roll 16 Surface treatment sputtering cathode 17 Cleaning treatment means 18 First can roll 19 Surface treatment ion source 20a Front feed roll 20b Rear feed roll 21 Second can Roll 22a-22d Sputtering cathode 23 Winding roll 30 Roll-to-roll continuous electroplating device 31 Electroplating tank 32 Unwinding roll 33a-33e Feeding roll 34a-34h Anode 35a-35d Reversing roll 36 Winding roll Le

Claims (9)

  A method for treating a surface of a resin film, comprising bringing at least one surface of the resin film into contact with an unoxidized active metal surface.   The resin film is a long resin film, and the long resin film is rolled on the outer peripheral surface of a surface treatment roll that has the metal surface on the outer peripheral surface and rotates following the conveyance of the long resin film. 2. The surface treatment method for a resin film according to claim 1, wherein at least one surface thereof is brought into contact while being conveyed by two rolls.   The transport of the long resin film is performed under a reduced pressure atmosphere, and the region in contact with the long resin film on the outer peripheral surface of the surface treatment roll comes to a position where it does not contact the long resin film due to the rotation. 3. The resin film surface treatment method according to claim 2, wherein the non-oxidized active metal surface is formed by sputtering means.   The region in contact with the long resin film on the outer peripheral surface of the surface treatment roll includes a position in contact with the long resin film by the rotation, and a position in which an unoxidized active metal surface is formed by the sputtering means. The method for surface treatment of a resin film according to claim 3, wherein a cleaning process is performed when the film comes between.   The resin film surface treatment method according to claim 4, wherein the cleaning treatment is plasma irradiation or ion beam irradiation.   The region in contact with the long resin film on the outer peripheral surface of the surface treatment roll is rotated by a cycle consisting of contact with the long resin film, the cleaning treatment, and formation of the unoxidized active metal surface. The resin film surface treatment method according to claim 4, wherein the method is repeated.   A method of manufacturing a copper-clad laminate in which a base metal layer and a copper coating layer are formed on at least one surface of the long resin film by a dry plating method, wherein the film formation is performed before the base metal layer is formed. A method for producing a copper-clad laminate, wherein the surface is subjected to surface treatment by the surface treatment method according to any one of claims 1 to 6.   A surface treatment apparatus for performing a surface treatment on a long resin film conveyed in a roll-to-roll manner in a decompression container, wherein the surface is in contact with the surface of the long resin film on a conveyance path of the long resin film A treatment roll is arranged, and when the region of the outer peripheral surface of the surface treatment roll that comes into contact with the surface of the long resin film comes within an angular range that does not contact the long resin film by rotation, A surface treatment apparatus for a long resin film, characterized in that a sputtering cathode is arranged at an opposing position.   When the region of the outer peripheral surface of the surface treatment roll that comes into contact with the surface of the long resin film comes within an angular range that does not contact the long resin film by rotation, 9. The long length according to claim 8, wherein a plasma irradiation source or an ion beam irradiation ion source is disposed in front of or behind the sputtering cathode with respect to a rotation direction of the surface treatment roll. Resin film surface treatment equipment.

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