JP2008050638A - Method of manufacturing metallized plastic film base material, and vacuum film deposition apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a metallized plastic film base material reduced in the amount of foreign matters deposited on a metallic film when depositing the metallic film on a surface of a plastic film, and to provide a vacuum film deposition apparatus therefor which is suitable for manufacturing a long product reduced in surface defects such as ruggedness as much as possible in a subsequent process. <P>SOLUTION: In the manufacturing method of the metallized plastic film base material, the metallized plastic film base material is manufactured by performing the film deposition of a metal on a plastic film by using a vacuum film deposition apparatus having a plastic film uncoiling means, a pretreatment device, a film deposition chamber demarcated by bulkheads, and a coiling means demarcated by the bulkheads in a vacuum container. After performing the film deposition of the metal on the plastic film, foreign matters deposited on a surface opposite to a metallic film deposition surface of the plastic film are removed, and the metallized plastic film base material is coiled. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for producing a metallized plastic film substrate by subjecting a plastic film to a metal film by sputtering or vapor deposition, and in particular, a conductive method suitably used for the production of a plating method two-layer circuit substrate. The present invention relates to a method for producing a metallized plastic film substrate and a vacuum film forming apparatus for producing the same.

  As electronic devices become smaller, lighter, more functional, more multifunctional, and more densely packed, printed wiring boards are becoming higher due to conductor widths and narrower conductors, multilayers, flexibility, and thinner substrates. The density is rapidly increasing, and it has been developed into a flexible printed circuit (hereinafter sometimes referred to as FPC) substrate.

  Conventionally, a so-called three-layer flexible printed wiring board is known in which a copper film as a conductor layer is bonded to a plastic film such as a polyimide film via an adhesive layer. The three-layer structure type flexible printed wiring board has a problem that the heat resistance of the adhesive used is inferior to that of the polyimide film, so that the dimensional accuracy after processing decreases, and the thickness of the copper foil used is usually Since the thickness is 10 μm or more, there is a disadvantage that patterning for high-density wiring with a narrow pitch is difficult. Further, when the IC is mounted, the adhesive is melted or thermally decomposed with respect to the IC heated to a high temperature, so that the IC bump and the lead on the FPC cannot be connected with high accuracy. Therefore, when mounting an IC, it is generally performed that a hole is punched at a position where the IC is mounted by a method such as punching so that no adhesive is interposed under the IC chip. Yes.

  On the other hand, a metal layer as a conductor layer was formed on a polyimide film by a wet plating method or a dry plating method (for example, a vacuum deposition method, a sputtering method, an ion plating method, etc.) without using an adhesive. A so-called two-layer structure type flexible printed wiring board is known. This plating method two-layer type flexible printed wiring board that does not use an adhesive (hereinafter sometimes referred to as a plating method two-layer circuit substrate) has no adhesive, so that it has been described above when mounting an IC. It is possible to mount the IC directly on the polyimide film without making a hole in the film surface. In addition, the flexible printed wiring board of this two-layer structure type can make the conductor layer thinner than 10 μm, so the FPC has very good flexibility and can handle fine pitch and high-density wiring. It is.

  Usually, said wet plating method is implemented by electrolytic plating (refer patent document 1-patent document 4).

  However, if deposits are present on the metal surface of the metallized plastic film substrate that is the base film for constituting the plating method two-layer circuit substrate, surface defects such as irregularities are likely to occur on the surface after the electrolytic plating. . That is, when a conductive foreign matter such as a metal piece is present on the metal surface of the metallized plastic film substrate, the metal by electrolytic plating is stacked thereon to form a protrusion. Moreover, when a nonelectroconductive foreign material exists in the metal surface of a metallized plastic film base material, since it does not plate on the foreign material, a dent will arise. In recent years, as the circuit pattern becomes very fine such as 30 μm, 20 μm or less, reduction of the surface defects has become a big problem.

  In a two-layer plating base material, it is generally known that a plastic film, which is a base film before plating, is subjected to glow discharge treatment, corona discharge treatment, plasma treatment or the like as pretreatment (see Patent Document 5). ). By these treatments, the surface of the plastic film is cleaned, and the conductive or non-conductive foreign matter and deposits on the plastic film as described above are removed, and the surface of the plastic film is hydrophilized, and the surface free energy Is increased, thereby enhancing the adhesion between the plastic film and the metal deposited by sputtering.

However, these techniques alone have become insufficient as the surface quality of the plating method two-layer circuit substrate in order to cope with the finer pitch of the circuit in recent years. As a result of intensive studies, the present inventors have conducted a pretreatment such as the above-described glow discharge treatment, followed by a dry plating process such as sputtering or vapor deposition, and then a metallized plastic film substrate on which a metal has been formed. When deposits are present on the non-dry plating surface during winding, after the metallized plastic film substrate is wound up, the foreign matter adhering to the back surface is transferred to the dry plating surface, followed by wet plating. In (electrolytic plating), it turned out that a protrusion and a dent generate | occur | produce due to the deposit | attachment which moved to the said plating surface.
Japanese Patent Laid-Open No. 2002-20898 Japanese Patent Laid-Open No. 2003-321796 JP 2003-147582 A Japanese Patent Laid-Open No. 9-235697 JP-A-1-321687

  The problem to be solved by the present invention is that an optimal conductive metal is used in order to minimize surface defects generated in the wet (electrolytic) plating process as described above when producing a plating method two-layer circuit substrate and the like. An object of the present invention is to provide a method for producing a plasticized plastic film substrate and a vacuum film forming apparatus for producing the same.

  Means for solving the above problems are as follows.

  The method for producing a metallized plastic film substrate of the present invention comprises a vacuum container having a plastic film unwinding means, a pretreatment device, a film forming chamber separated by a partition, and a winding means separated by the partition. In a method of manufacturing a metallized plastic film substrate by forming a metal film on a plastic film using a film forming apparatus, after the metal film forming process on the plastic film, the opposite of the metal film forming surface of the plastic film A method for producing a metallized plastic film substrate, comprising removing a foreign matter adhering to the surface and then winding the metallized plastic film substrate.

  According to a preferred embodiment of the method for producing a metallized plastic film substrate of the present invention, it is possible to remove a foreign substance by bringing a slightly adhesive roll into contact with the surface opposite to the metal film-forming surface of the plastic film. The adhesive force of the slightly adhesive roll is preferably as weak as possible, and it is preferable that the adhesive substance is not transferred when it is brought into contact with the plastic film to be formed. The surface of the plastic film can be of any kind, such as silicon rubber and butyl rubber, as long as it is contacted while rolling over the plastic film with foreign matter on it, and the attached foreign matter is transferred to the roll side. It is preferable to select one having a change in contact angle with pure water of 30 ° or less before and after contact with the slightly adhesive roll. When the change in the contact angle exceeds this value, the slightly sticky substance is transferred to the film surface, and when this is used for the production of a plating method two-layer circuit substrate, the transferred substance is applied to the plating film in the subsequent plating step. There is a possibility of inhibiting the adhesion, which is not preferable.

  According to a preferred embodiment of the method for producing a metallized plastic film substrate of the present invention, the nonwoven fabric travels on the opposite surface of the plastic film on the metal film-forming surface in the same direction as or in the opposite direction to the direction of transport of the plastic film. To remove foreign matters.

  When the present invention is applied to the production of a plating method two-layer type circuit substrate, according to a preferred embodiment of the method for producing a metallized plastic film substrate, the metal film forming process is sputtering.

  The metallized plastic film substrate produced by the above-described method for producing a metallized plastic film substrate of the present invention can be made into a two-layer circuit substrate by subjecting it to wet electrolytic plating.

  Further, the vacuum film forming apparatus of the present invention is separated by a partition for forming a metallized plastic film substrate by forming a metal film on the plastic film in the vacuum container. In a vacuum film forming apparatus having a film forming chamber and a winding means for a metallized plastic film substrate separated by a partition, the metallized plastic film substrate after the film forming chamber separated by the partition The vacuum film forming apparatus is characterized in that a foreign matter removing means for removing foreign matter adhering to the surface opposite to the metal film forming surface of the plastic film is arranged before the winding means.

  According to a preferred aspect of the vacuum film-forming apparatus of the present invention, the foreign matter removing means has a nonwoven fabric unwinding means, a nonwoven fabric winding means, and a mechanism for bringing the nonwoven fabric into contact with a plastic film. It has a function of removing the adhered foreign matter while being wound by the means.

  According to a preferred aspect of the vacuum film forming apparatus of the present invention, the foreign matter removing means is a slightly adhesive roll, and a change in a contact angle with pure water on the surface before and after contacting with the slightly adhesive roll on the surface of the plastic film. Is less than 30 °.

  The metallized plastic film substrate can be advantageously produced by the vacuum film forming apparatus of the present invention.

  In the present invention, the plastic film is preferably used for a long plastic film. The long length is usually used for a plastic film having a width of 5 m or less and a length of 10 m or more.

  According to the present invention, when forming a conductive metal film on the surface of the plastic film, it is possible to remove foreign matter (adhered matter) on the back side of the plastic film immediately before winding after vacuum film formation. Long length of plating method two-layer circuit substrate, etc., with no foreign matter (adhered matter) transferred onto the metal film-forming surface of the plastic film after winding, and less surface defects such as protrusions and dents in post-processing A metallized plastic film substrate suitable for the manufacture of the product is obtained. When a circuit pattern is formed on the plating method two-layer circuit material manufactured using the metallized plastic film substrate manufactured according to the present invention, actual damage such as short circuit or disconnection of the circuit can be reduced.

  Next, the embodiment of the manufacturing method of the metallized plastic film base material of this invention is described using drawing.

  In the method for producing a metallized plastic film substrate of the present invention, a vacuum film forming apparatus as shown in FIG. 1 can be used. FIG. 1 is a schematic side view showing an example of the structure in the vacuum chamber of the vacuum film forming apparatus of the present invention.

  In FIG. 1, in the vacuum container 1, an unwinding chamber, a film forming chamber, and a winding chamber are separated by a partition wall, and are arranged and arranged in this order. In the unwinding chamber, the plastic film 2 mounted on the unwinding means 3 passes through a pretreatment device 4 (glow discharge treatment, etc.) and is held by a cooling roll 5 in the film forming chamber, and a desired metal material is sputtered or metalized. A metal film is formed on the plastic film 2 by vapor deposition or the like. Here, examples of the pretreatment process performed by the pretreatment apparatus 4 include glow discharge treatment, corona discharge treatment, and plasma treatment, and these usually have an adhesive force with a substance to be formed by hydrophilizing the surface of the plastic film 2. Although it is performed for the purpose of increasing the thickness, it is desirable to treat only the surface on which the metal is formed by sputtering or metal vapor deposition, and to prevent the treatment effect from being exerted as much as possible on the opposite surface where no film is formed. If the opposite side of the metal film processing surface of the plastic film 2 is processed, blocking will occur after winding the metallized plastic film substrate, and the sputtering surface and metal deposition surface will peel off, resulting in the occurrence of pinholes, etc. It can be a cause.

  In the example of FIG. 1, four sputtering cathodes 6 are installed, and a metal material to be deposited is installed here to perform sputtering. A metallized plastic film base material on which a metal film has been processed is conveyed in the direction of the arrow while being supported by a guide roll 9 or the like, and is disposed in front of (in the vicinity of) the winding means 7 in the winding chamber. The foreign matter adhered by 10 is removed, and then the metalized plastic film substrate is wound up by the winding means 7.

  In FIG. 1, the vacuum container 1 is separated into three chambers, an unwinding chamber, a film forming chamber, and a winding chamber, by a partition wall and a slit roll 8, and a pretreatment device 4 is installed in the unwinding chamber. If necessary, a pretreatment chamber for the pretreatment device 4 may be separately installed. In the case where there is a difference in the set vacuum degree between these chambers, the plastic film 2 and the metallized plastic film substrate are transported between the chambers via the slit roll 8. Furthermore, when it is necessary to make a large difference in the degree of vacuum between the chambers, a buffer chamber may be provided between the chambers. In each chamber, it is possible to maintain a desired degree of vacuum using various commonly used pumps such as a rotary pump, a diffusion pump, and a turbo molecular pump.

  The plastic film 2 and the metallized plastic film substrate in the vacuum container 1 can be carried by a roll driven by a motor and several guide rolls 9. The guide roll 9 may have a driving force by a motor or may be a free rotating roll.

The plastic film 2 is transported while being supported by several guide rolls 9 as a metallized plastic film substrate after sputtering or metal deposition, and is wound up by the winding means 7. Here, the adhering substance removing means 10 is installed before winding the metalized plastic film substrate, and the adhering foreign matter is removed on the opposite side of the surface of the plastic film 2 on which sputtering or metal deposition is performed. It is an important element of the invention. The winding chamber is separated from the film forming chamber where sputtering and metal deposition are performed by a partition wall, and the appearance of the metallized plastic film substrate in the winding process is improved by making a difference in the degree of vacuum of both chambers. Thus, the effect of preventing poor flatness can be obtained. Specifically, the film forming chamber is generally set to a vacuum degree of about 10 ⁻¹ Pa, but the winding chamber is preferably 10 ^−0.5 Pa or lower than that. . A preferable range of the vacuum degree of the film forming chamber is 5 × 10 ⁻⁰ to 5 × 10 ⁻² Pa, and a preferable vacuum degree of the winding chamber is 1 × 10 to 1 × 10 ⁻¹ Pa. It is a range.

  FIG. 2 is a schematic side view showing an example of a winding mechanism of a winding chamber in the vacuum film forming apparatus of FIG. The metallized plastic film base material on which the metal layer is formed in the film forming chamber is transferred to the winding chamber via the slit roll 8 and the foreign matter removing means 10 disposed in front of (in the vicinity of) the winding means 7. After the foreign matter adhering to the surface is removed, it is wound on the winding means 7 through the guide roll 9.

  In the present invention, one of the preferred embodiments of the foreign matter removing method is that a non-woven fabric traveling in the same direction as or opposite to the conveying direction of the plastic film 2 is brought into contact with the opposite surface of the plastic film 2 to the metal film forming surface. To remove foreign matter. In FIG. 2, the nonwoven fabric 13 released from the nonwoven fabric unwinding means 11 and wound on the nonwoven fabric winding means 12 by motor driving is applied to the back surface of the metallized plastic film substrate that has been transported to remove the adhered foreign matter. It is to follow. The nonwoven fabric 13 is preferably selected from a material that does not generate dust as much as possible. The conveyance direction of the nonwoven fabric 13 may be the same as or opposite to the conveyance direction of the metallized plastic film substrate. Depending on the type of plastic film 2 and the type of nonwoven fabric 13, a method in which scratches or the like hardly occur on the plastic film 2 can be selected. The material of the fibers constituting the nonwoven fabric is not particularly limited, such as polyester, nylon, rayon, etc., but the removal amount of the adhered foreign matter is maximized by the pressing amount and pressure as long as the surface of the plastic film is not scratched. Conditions can be defined.

  In the present invention, another embodiment of the foreign matter removing method includes a method using a slightly adhesive roll. FIG. 3 is a schematic side view showing another example of the winding mechanism of the winding chamber in the vacuum film forming apparatus of FIG. In FIG. 3, the fine adhesive roll 14 as the foreign matter removing means removes the foreign matter from the metallized fine adhesive roll 14. The material of the slightly adhesive roll is not particularly limited, but a material based on butyl rubber or silicon rubber can be used. For example, Miyagawa Roller Co., Ltd. MIMOSA ST, MIMSOA B-MT, TEKNEK XCH390, etc. can be selected according to the type of plastic film. The diameter of the slightly adhesive roll is preferably as large as possible within the range that can be installed in the film forming apparatus.

  As the type of the slightly adhesive roll 14, (a) a type in which one slightly adhesive roll 14 is applied to a metallized plastic film substrate and the surface of the slightly adhesive roll 14 is cleaned for each batch, and (b) the adhesive sheet is used as a roll. A type in which the pressure-sensitive adhesive roll 14 is applied to the surface of the metallized plastic film substrate and the pressure-sensitive adhesive sheet is exchanged for each batch. The type that replaces the adhesive sheet can be selected as necessary.

  It is preferable to select an appropriate range of the adhesive strength of the slightly adhesive roll 14 for a plastic film on which a metal film is formed. In addition, it is preferable to select a material having a low-molecular-weight bleed-out from the pressure-sensitive adhesive surface as much as possible.

  According to a preferred embodiment of the method for producing a metallized plastic film substrate of the present invention, it is preferable to use a slightly adhesive roll having as little adhesive force as possible to the plastic film surface. The adhesive strength is qualitatively 10 hPa or less (substantially exfoliated) when a 1 cm wide film sample is held on a slightly adhesive material wound around a roll and a 50 g load is applied and then peeled off by a tensile tester. Material that cannot be measured because the force is too small can be selected. The lower limit of the adhesive strength is not measurable by the measurement method of the present inventors, but a small amount of fine powder such as magnesium oxide is sprayed on the plastic film surface, and the fine powder is roughly formed by rolling the date adhesive roll on it. Since there is almost nothing removed and reattached to the plastic film surface, it is possible to evaluate the slight adhesive force.

  As will be described later, the adhesive force can be forcibly amplified and evaluated, but the suitability range in this case is 200 to 800 hPa.

  The measurement of the adhesive force when the adhesive force is forcibly amplified can be performed as follows. Attach a stainless steel rectangular data base that can superimpose two upper and lower horizontal planes of 10 mm square to a tensile tester, attach a piece of adhesive material on one side, and a piece of plastic film on the other side using double-sided adhesive tape After applying a 3 kg overload for 10 seconds at normal temperature and humidity, a tensile test is performed, and the maximum stress when the adhesive material and the plastic film are peeled is defined as the adhesive strength. In the adhesive force by such a forced test, the suitable range of the adhesive force with respect to a plastic film is 200-800 hPa.

  Moreover, when making the slightly adhesive roll 14 contact the metallized plastic film base material conveyed, if the holding angle of a metallized plastic film base material is enlarged too much, it may cause a wrinkle and flatness defect. The range of an appropriate holding angle is preferably 1 to 50 °, more preferably 5 to 30 °. The holding angle is designed geometrically as an angle formed by a contact point at the time of entering and leaving the roll when the roll is pressed against the plastic film surface.

  In the present invention, to prevent the metallized plastic film substrate from being wound around the slightly adhesive roll 14, the roll is driven immediately after or slightly after the slightly adhesive roll 14, and after the slightly adhesive roll 14 compared to before the slightly adhesive roll 14. Draw may be applied so that the speed of the metallized plastic film substrate is slightly increased. The value of the draw is about 0.1% or less as a general value in the conveyance of the metallized plastic film substrate.

  In addition, as an index of a preferable form of the surface of the slightly adhesive roll, there is a change amount of the contact angle. It is preferable that the adhesive roll is rolled back and forth on the plastic film, and the change in contact angle with pure water before and after that does not exceed 30 °.

  FIG. 4 is a schematic cross-sectional view illustrating the side structure of the metallized plastic film substrate obtained in the present invention. In FIG. 4, a metallized plastic film substrate 21 has a conductive layer 16 formed on a plastic film 2 by sputtering or metal vapor deposition, and a conductive layer 15 formed thereon.

  The conductive layer 16 includes a nichrome layer, and the conductive layer 15 includes a copper layer. In addition, as a metal that can be used for the conductive layer 16, in addition to nichrome, metal chromium, nickel, titanium, molybdenum, cobalt, and the like can be used.

  Plating method In the manufacturing method of two-layer circuit base material, when it is going to perform electroplating on the metallized plastic film base material obtained by sputtering or metal vapor deposition, conductive foreign matter adheres to the sputtering or metal vapor deposition surface. If so, the plating rides on the foreign matter and a projection is formed. Further, when non-conductive foreign matter is adhered, the plating does not get on and a dent or pinhole is formed.

  Examples of the plastic film used in the present invention include polyesters such as polyethylene terephthalate, polyethylene-2,6-naphthalate and polyethylene-α, β-bis (2-chlorophenoxyethane 4,4′-dicarboxylate), polyphenylene sulfide. , Polyethersulfone, polyetheretherketone, aromatic polyamide, polyarylate, polyimide, polyamideimide, polyetherimide, polyparazic acid, polyoxadiazole, and plastic films made of polymers such as halogen group or methyl group substituted products thereof Is mentioned. Further, a plastic film made of a copolymer of these polymers or a polymer containing another organic polymer may be used.

  These plastic films may be added with known additives such as lubricants and plasticizers. The polyimide film is excellent in heat resistance during solder mounting and the like, and is suitably used for the application of the present invention. Polyethylene terephthalate is inexpensive and easy to handle unless it is mounted by soldering.

  In the present invention, the plastic film is subjected to pretreatment by the pretreatment apparatus, and then subjected to sputtering or metal vapor deposition. The metal to be sputtered or vapor-deposited is not particularly limited, but in the case of a plating method two-layer circuit substrate, nickel, chromium, titanium, molybdenum and copper and alloys thereof are generally used as the cored layer. It is.

  The thickness of the plastic film used in the present invention is preferably 10 μm or more from the viewpoint of transportability, and the concept of a plastic film has an upper limit of 200 μm at most. Moreover, in the case of the plating method two-layer circuit substrate use, the lower limit of the thickness of the conductive metal layer provided on the plastic film is not particularly limited as long as the electric resistance value becomes 1Ω or less during the plating process. However, the upper limit of good productivity without causing wrinkles or flatness in sputtering or metal vapor deposition is about 5000 angstroms. The metallized plastic film substrate obtained by sputtering or metal-depositing a conductive metal layer is preferably subjected to pretreatment such as acid treatment, degreasing treatment, and water washing treatment before introducing the plating tank. If the deposit on the sputtering or metal deposition surface is sufficiently removed as in the case of a metal deposition film, and plating is performed while the metal surface is not oxidized after sputtering or metal deposition, The preprocessing as described above may be omitted.

  The metallized plastic film substrate produced by the method for producing a metallized plastic film substrate of the present invention can produce a two-layer circuit substrate by subjecting it to wet electrolytic plating.

  When a metallized plastic film substrate is used as a plating method two-layer circuit substrate, the metallized plastic film substrate imparted with conductivity by sputtering or metal vapor deposition is subjected to electrolytic plating on the conductive surface. The In this application, the metal to be sputtered or vapor-deposited on the plastic film is preferably in the same position as the metal to be electroplated, and in particular, the metal species of the metal layer formed by sputtering or metal-deposited layer and plating. Are preferably the same. Since copper is usually used for electrolytic plating, it is preferable to use copper as the metal for sputtering or metal deposition. When copper is oxidized, it tends to diffuse into many plastic films such as polyimide and polyethylene terephthalate, which leads to a decrease in insulation reliability between circuit patterns when used as a circuit material. . In order to prevent these problems, it is desirable to provide a barrier layer on the plastic film before sputtering or metal deposition of copper on the plastic film. As the metal used for this barrier layer, nickel, chromium or an alloy thereof is suitable.

  After performing plating treatment with the current applied adjusted to the desired thickness in the plating tank, perform post-treatment steps such as a water washing tank, rust prevention treatment and drying to remove the plating solution as necessary. Thus, a two-layer type circuit material (substrate) can be obtained.

  FIG. 5 is a perspective view showing an example of the structure of a plating apparatus for performing electrolytic plating on the metallized plastic film substrate obtained in the present invention.

  The plating apparatus shown in FIG. 5 includes a plating solution tank 26 for containing a plating solution and a plating solution in the plating solution tank 26 while transporting the metallized plastic film substrate 21 in the longitudinal direction with its width direction directed up and down. An electroplating apparatus having a conveying means for dipping and a power supply means that is in electrical contact with the conductive surface of the metallized plastic film substrate 21, and is used as a drive roll 23 and a power supply means that are used as the conveyance means. Both of the power feeding rolls 24 are provided outside the plating solution tank 26, and the power feeding roll 24 has substantially no driving force and is configured to rotate by following the metallized plastic film substrate 21 to be conveyed. An anode (anode) 22 that generates electrolysis with the plastic film substrate 21 is disposed in the plating bath 26. The power supply roll 24 installed on both sides of the metallized plastic film base 21 and used as power supply means (cathode) is installed only on one side of the metallized plastic film base 21 and is metallized from the power supply roll 24. Power is supplied to the plastic film base 21.

  In FIG. 5, a plating solution tank 26 in the power supply unit 27 is a part that accommodates the plating solution. A pair of side walls facing the plating solution tank 26 are provided with slits through which the metallized plastic film substrate 21 can enter and exit. The plating solution tank 26 is usually provided with an anode 22 as an electrode immersed in the plating solution. The anode 22 can be installed on one side or both sides depending on the surface of the metallized plastic film substrate 21 to be plated. In the present invention, since the metal layers are provided on both sides of the metallized plastic film substrate 21, the anode 22 can be installed on both sides. The conveying means immerses the metallized plastic film substrate 21 in the plating solution in the plating solution tank 26 while conveying the metallized plastic film substrate 21 to be plated in the longitudinal direction with the width direction facing up and down. Means.

  In the plating apparatus shown in FIG. 5, the drive roll 23 corresponds to a conveying means, and rotates with a driving force to assist the metallized plastic film substrate 21 and the plated plating method two-layer circuit substrate 29. It is sandwiched between the rolls 25 and transported in the direction indicated by the arrow MD (hereinafter sometimes referred to as the transport direction MD). Further, if necessary, an auxiliary roll 25 is additionally installed in the vicinity of the drive roll 23 or the power supply roll 24, and the metallized plastic film substrate 21 and the plated plating two-layer circuit substrate 29 and the drive roll 23 or An appropriate holding angle may be provided between the power supply roll 24 and the power supply roll 24.

The drive roll 23 is preferably made of a material having corrosion resistance to the plating solution because it prevents the roll material from being deteriorated by contact with the plating solution. In the present invention, “having corrosion resistance” means that there is no weight change or discoloration for 6 months in the immersion test using a plating solution. When the roll deteriorates due to the plating solution, the roll surface roughness and roll diameter change, and the metallized plastic film substrate 21 cannot be stably conveyed. Therefore, it is a particularly preferable aspect that the drive roll 23 is disposed outside the plating solution tank 26 to avoid contact with the plating solution.
The power supply electrode is an electrode that is in electrical contact with the metallized plastic film substrate 21 and supplies power so that a portion to be plated of the metallized plastic film substrate 21 becomes a cathode for the anode 22 described above. In the plating apparatus illustrated in FIG. 5, the power supply roll 24 corresponds to a power supply electrode.
The plating apparatus can increase the number of plating baths 26 according to the thickness of the target conductive layer, the speed of the metallized plastic film substrate 21 and the plating method two-layer circuit substrate 29 to be conveyed. At that time, the metallized plastic film substrate 21 and the plated plating method two-layer circuit substrate 31 can be stabilized by configuring the power supply unit 27 having the conveyance / power supply rolls on both sides of the plating solution tank 26 as one unit. Can be conveyed.

  Using such a plating apparatus, the plating solution tank 26 is filled with a plating solution, and a current is passed between the anode 22 and the power supply electrode, whereby the metallized plastic film substrate 21 is plated and two plating methods are applied. The circuit substrate 31 can be manufactured.

  After performing plating treatment with the current applied adjusted to the desired thickness in the plating bath, post-treatment steps such as washing bath, rust prevention treatment and drying to remove the plating solution were performed as necessary. Thereafter, the intended plating method two-layer type circuit material (substrate) can be obtained.

  FIG. 6 is a schematic cross-sectional view showing an example of the structure of a plating method two-layer circuit substrate 31 in which electrolytic plating is performed on the metallized plastic film substrate obtained in the present invention.

  In FIG. 6, the plated plating two-layer circuit substrate 29 shown in FIG. 4 has the conductive layer 16 formed on the plastic film 2 by sputtering or metal vapor deposition, and the conductive layer 15 formed thereon. A plated layer 28 is further formed on the metallized plastic film substrate 21 by a plating apparatus.

  The metallized plastic film substrate obtained in the present invention is suitable for the production of a plating method two-layer type flexible printed wiring board (plating method two-layer circuit substrate). In addition to COF (chip-on-flex) circuit board applications in which ICs are directly mounted on this plated two-layer circuit substrate, IC card and IC tag antenna circuits, and thin-film circuit components for small electronic devices such as mobile phones Etc., such as various FPC applications, electromagnetic wave shielding materials for flat panel displays, and outer conductors of coaxial cables. As a method for forming a circuit pattern, a subtractive method or a semi-additive method is used, and is not particularly limited.

  Hereinafter, a method for producing a metallized plastic film substrate using the sputtering and metal deposition method of the present invention, and a plating method using the metallized plastic film substrate (FIG. 4) obtained thereby (FIG. 4) (FIG. 4) The production method 6) will be described as an example, but the present invention is not limited to these examples.

<Evaluation of surface quality>
Observe the copper film surface of the metallized plastic film (polyimide film with copper film) substrate (50 mm x 500 mm) with a stereomicroscope (x40), and mark the surface defects with a size of 20 μm or more. Concavities and convexities were measured with a laser microscope (manufactured by Keyence Corporation, VK8500), judged to be protrusions or dents, and dents with a depth of 2.0 μm or more were counted. The copper layer of the dent part detected here is removed by etching, and defects caused by the unevenness of the polyimide film surface are omitted and not counted. In the evaluation of the surface quality after plating, eight portions were evaluated every about 300 m with respect to a portion of the original fabric having a length of 3000 m from which the portion of 300 m from the outermost winding and the portion of 300 m from the winding core were removed.

(Example 1)
A polyimide film “Kapton EN” (registered trademark) (manufactured by Toray DuPont, thickness 38 μm, width 520 mm, length 3000 m) was used as the insulating plastic film. Using the sputtering apparatus shown in FIG. 1, a nickel / chrome layer having a thickness of 300 angstroms is formed on one surface of a polyimide film, and a copper layer having a thickness of 1500 angstroms is further formed thereon, as shown in FIG. A metallized plastic film substrate with a conductive layer having a cross-sectional structure was produced. Here, just before the winding means in the winding chamber, a slightly adhesive roll MIMASA B-ST manufactured by Miyagawa Roller Co., Ltd. was used as a foreign matter removing means only on the side opposite to the sputtering film forming surface. Here, the degree of vacuum in the film forming chamber was in the range of 1 × 10 ⁻¹ Pa to 1 Pa, and the degree of vacuum in the winding chamber was in the range of 5 × 10 ⁻¹ Pa to 5 Pa. The holding angle of the slightly adhesive roll was 18 °, and the conveyance speed of the plastic film was 3.0 m / min. The slightly adhesive roll does not have a driving force for rotating itself, and is rotated by contacting a plastic film to be conveyed. The change in contact angle with pure water before and after the slightly adhesive roll used here was brought into contact with the polyimide film (Kapton EN) was 21 °. (51 ° before contact, 72 ° after contact)
A conductive metallized plastic film base material obtained by sputtering nickel / chromium alloy and copper on a plastic film obtained as described above, and a plating apparatus in which eight plating solution tanks shown in FIG. 5 are arranged in series Was used for electrolytic plating. Copper was used for the anode, a copper sulfate plating solution was used for the electrolytic solution, and electrolytic copper plating having a thickness of 8 μm was performed on the above-mentioned long metallized plastic film substrate.

(Example 2)
In Example 1, a polyimide film (metallized plastic film substrate) with a copper film was produced in the same manner as in Example 1 except that XCH390 made by TEKNEK was used as the slightly adhesive roll for the foreign matter removing means. The metallized plastic film substrate thus obtained was subjected to electrolytic copper plating in the same manner as in Example 1 to prepare a plating method two-layer circuit substrate.

(Example 3)
In Example 1, a polyimide film (metallized plastic film substrate) with a copper film was produced in the same manner as in Example 1 except that a non-woven fabric conveyance device was installed as the foreign matter removing means. As shown in FIG. 2, the nonwoven fabric conveying device is provided with a nonwoven fabric winding means and a nonwoven fabric unwinding means. As the nonwoven fabric, a polyester nonwoven fabric (weight per unit 40 g / m ² , thickness 0.29 mm) is used, and the polyimide film is conveyed. The deposits were removed while winding in the same direction as the direction at a speed of 0.1 m / min. The metallized plastic film substrate thus obtained was subjected to electrolytic copper plating in the same manner as in Example 1 to prepare a plating method two-layer circuit substrate.

(Comparative Example 1)
In Example 1, a polyimide film with a double-sided copper film (metallized plastic film base) was prepared in the same manner as in Example 1 except that the sputtering was performed with the slightly adhesive roll as the winding means in the winding chamber removed. Material). The metallized plastic film substrate thus obtained was subjected to electrolytic copper plating in the same manner as in Example 1 to prepare a plating method two-layer circuit substrate.

  Tables 1 and 2 show the results of evaluating the surface quality of the two-layer type circuit material (FIG. 6) obtained in Examples 1 to 3 and Comparative Example 1 in accordance with the above method.

  In the present invention, the plating method two-layer circuit base material prepared by electrolytic plating of a dry-plated conductive long metallized plastic film base material has a good surface state with few surface defects.

  Since the metallized plastic film substrate obtained in the present invention is a metallized plastic film substrate with reduced adhesion foreign matter on the metal film, a long product with very few surface defects such as irregularities is produced in subsequent processing. Can be useful.

FIG. 1 is a schematic side view showing an example of the structure in the vacuum chamber of the vacuum film forming apparatus of the present invention. FIG. 2 is a schematic side view illustrating an example of a winding mechanism of a winding chamber in the vacuum film forming apparatus of FIG. FIG. 3 is a schematic side view showing an example of another winding mechanism of the winding chamber in the vacuum film forming apparatus of FIG. FIG. 4 is a schematic cross-sectional view illustrating the side structure of the metallized plastic film substrate of the present invention. FIG. 5 is a perspective view showing an example of the structure of a plating apparatus for performing electrolytic plating on the metallized plastic film substrate obtained in the present invention. FIG. 6 is a schematic cross-sectional view showing an example of the structure of a plating method two-layer circuit base material obtained by performing electrolytic plating on the metallized plastic film base material obtained in the present invention.

Explanation of symbols

1. 1. Vacuum container 2. Plastic film Unwinding means 4. 4. Pretreatment device 5. Cooling roll 6. Sputtering cathode Winding means 8. Slit roll9. Guide roll 10. Foreign matter removing means 11. Nonwoven fabric unwinding means 12. Nonwoven fabric winding means 13. Nonwoven fabric 14. 14. Lightly adhesive roll Conductive layer 16. Conductive layer 21. Metallized plastic film substrate 22. Anode 23. Drive roll 24. Feeding roll 25. Auxiliary roll 26. Plating bath 27. Power supply unit 28. Plating layer 29. Plating method 2-layer circuit substrate

Claims (8)

  In a vacuum container, metal film is formed on plastic film using a vacuum film forming device having a plastic film unwinding means, a pretreatment device, a film forming chamber separated by a partition wall, and a winding means separated by a partition wall. In the method of manufacturing the metallized plastic film substrate, after the metal film is formed on the plastic film, the foreign matter adhering to the opposite surface of the metal film processed surface of the plastic film is removed, and then the metallized plastic A method for producing a metallized plastic film substrate, comprising winding up the film substrate.   2. The method for producing a metallized plastic film substrate according to claim 1, wherein a foreign matter is removed by bringing a slightly adhesive roll into contact with the surface opposite to the metal film forming surface of the plastic film.   2. The metallized plastic according to claim 1, wherein a non-woven fabric running in the same direction as or in the opposite direction to the direction of transport of the plastic film is brought into contact with the surface opposite to the metal film-forming surface of the plastic film to remove foreign matter. A method for producing a film substrate.   4. The method for producing a metallized plastic film substrate according to claim 1, wherein the metal film forming process is sputtering.   The plating method two-layer circuit base material formed by wet-electrolytic plating to the metallized plastic film base material obtained with the manufacturing method of the metallized plastic film base material in any one of Claims 1-4.   In a vacuum vessel, the film was separated by a partition for separating the plastic film unwinding means, pre-processing device, partition for separating the metal into a metallized plastic film by forming a metal film on the plastic film. In a vacuum film forming apparatus having a winding means for a metallized plastic film substrate, the plastic film is provided after the film forming chamber separated by the partition and before the winding means for the metallized plastic film substrate. A vacuum film forming apparatus comprising a foreign substance removing means for removing foreign substances adhering to the opposite surface of the metal film forming surface.   The foreign matter removing means has a mechanism for bringing the nonwoven fabric unwinding means, the nonwoven fabric winding means, and the nonwoven fabric into contact with the plastic film, and removing the adhered foreign matter while the nonwoven fabric is being wound by the winding means. The vacuum film-forming apparatus according to claim 6.     7. The foreign matter removing means is a slightly adhesive roll, and the change in contact angle with pure water on the surface before and after contacting with the slightly adhesive roll on the surface of the plastic film is 30 ° or less. Vacuum film forming equipment.