TW202000477A - Manufacturing method of coated metal laminated plate, manufacturing method of coated pressurizing roller and repairing method a coating layer moves synchronously with the pressurizing roller - Google Patents

Abstract

The invention provides a manufacturing method of a metal foil coated plate, a manufacturing method of a coated pressurizing roller and a repairing method thereof. The concave-convex surface of the metal foil is non-uniformly filled with the polyimide film, and the adhesion of the polyimide film and the metal foil is high. A metal foil (100) is fabricated by thermally crimping a polyimide film (10) with a metal foil (20) as a metal foil after the polyimide film (10) and the metal foil (20) continuously passing between a pair of pressurizing rollers (30) and a pressurizing roller (40). Hot pressing is conducted under the circumstances where a pressing surface of the pressurizing roller (30) on one side of the pair of the pressurizing rollers (30) and the pressurizing roller (40) is covered by a coating layer (50) which is used as a film-like buffer material, and the coating layer (50) can move synchronously with the pressurizing roller (30).

Description

Manufacturing method of metal-clad laminate, manufacturing method of coated pressure roller and repairing method

The present invention relates to a method for manufacturing a metal-clad laminate that can be used in flexible printed circuits (FPC) and the like used in electronic products, a method for manufacturing a coated pressure roller that can be used in the method, and a repair method.

The FPC can be manufactured by etching the copper layer of a copper-clad laminate (CCL) obtained by laminating a resin layer and a copper layer to perform circuit wiring processing. Regarding the CCL used in the FPC, a single-sided copper-clad laminate (hereinafter referred to as a single-sided CCL) that laminates copper foil only on one side of the resin layer is known, and double-sided copper-clad laminates of copper foil are deposited on both sides of the resin layer Laminate (hereinafter referred to as two-sided CCL).

As a manufacturing method of CCL, for example, a lamination method using a metal pressure roller and thermally bonding copper foil and a resin film is known (for example, refer to Patent Document 1 and Patent Document 2).

In addition, regarding the lamination method, when laminating the liquid crystal polymer film and the metal foil, in order to improve the appearance of the laminate, a fluororubber having a thickness of 0.02 mm to 5 mm is provided on the surface of the metal pressure roller , Silicone rubber or polyimide resin coating layer (for example, refer to Patent Document 3). [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2001-129918 (Patent Application etc.) [Patent Document 2] Japanese Patent Laid-Open No. 2009-66911 (Figure 2 etc.) [Patent Document 3] Japanese Patent Laid-Open No. 4398179 (Patent Application etc.)

[Problems to be solved by the invention]

In recent years, due to the high-definition and multi-functionalization of displays of mobile devices such as smart phones, the miniaturization of wiring has been promoted for FPCs used in the connection of components in the casings of these devices. Along with this, regarding the CCL that functions as a connecting component by processing the deposited copper foil to form wiring, the quality required for the adhesion between the copper foil and the resin layer is more stringent. However, when the metal foil and the polyimide film are laminated by the lamination method, the adhesion of the bonding surface and the filling of the thermocompression bonding surface are likely to be insufficient, which may lead to wiring during fine wiring processing Peel off. Therefore, an object of the present invention is to provide a metal-clad laminate in which the polyimide film fills the unevenness of the surface of the metal foil without unevenness, and the adhesion between the polyimide film and the metal foil is high. [Technical means to solve the problem]

The present inventors have repeatedly studied hard and found that when a metal-clad laminate is manufactured by a lamination method, the state of the pressing surface of at least one pressure roller among the pair of pressure rollers is covered by a film-shaped buffer material The thermocompression bonding is carried out under the circumstances, and the above problems can be solved, thereby completing the present invention.

That is, the manufacturing method of the metal-clad laminate of the present invention is to overlap the polyimide film and the metal foil by overlapping the polyimide film and the metal foil and continuously passing between a pair of pressing rollers A method of manufacturing a metal-clad laminate by thermocompression bonding. Furthermore, the method for manufacturing a metal-clad laminate according to the present invention is characterized by performing thermal compression bonding in a state where at least one of the pressure rollers of the pair of pressure rollers is covered with a film-like cushioning material. The film-shaped cushioning material can move in synchronization with the pressing roller, and the film-shaped cushioning material includes a non-thermoplastic polyimide layer containing non-thermoplastic polyimide.

In the method of manufacturing a metal-clad laminate of the present invention, the film-shaped buffer material may form a coating layer that covers the surface of the one-side pressure roller in the circumferential direction.

In the method of manufacturing a metal-clad laminate of the present invention, the one-side pressure roller may be a coated pressure roller having the coating layer, and the other pressure roller may be a metal roller.

In the method for manufacturing a metal-clad laminate of the present invention, the metal roller may be arranged on the metal foil side.

In the method of manufacturing a metal-clad laminate of the present invention, the film-shaped buffer material may be formed in a ring shape, and may be rotatably formed by the one-side pressure roller and a plurality of guide rollers.

In the method of manufacturing a metal-clad laminate of the present invention, the film-shaped buffer material may be formed into a long strip and transported in a roll-to-roll manner.

In the method of manufacturing a metal-clad laminate of the present invention, the thickness of the film-shaped buffer material may be in the range of 1 μm to 200 μm.

In the method for manufacturing a metal-clad laminate of the present invention, the polyimide film may include a single-layer or multi-layer polyimide layer, at least one layer may be a non-thermoplastic polyimide, and may be at least one The surface on the side where the metal foil is thermocompression-bonded is a thermoplastic polyimide layer.

In the method for manufacturing a metal-clad laminate according to the present invention, the polyimide film may be a laminated structure including a base material and a polyimide layer formed on the base material in layers.

In the method of manufacturing a metal-clad laminate of the present invention, the substrate may be copper foil.

The manufacturing method of the coated pressure roller of the present invention is to heat and press the polyimide film and the metal foil by overlapping the polyimide film and the metal foil and continuously passing between a pair of pressure rollers Next, a method of manufacturing a coated pressure roller used when manufacturing a metal-clad laminate. Furthermore, the method of manufacturing a coated pressure roller of the present invention is characterized in that the coated pressure roller includes a metal roller and a coating layer, the coating layer covers the surface of the metal roller in the circumferential direction, and the coating The manufacturing method of the pressure roller includes: A step of applying a resin solution of polyimide or a precursor of polyimide on the surface of the metal roller; and The step of forming the coating layer by completing the heat treatment of the resin solution on the metal roller.

In the method of manufacturing a coated pressure roller of the present invention, the resin solution may be applied to the surface of the metal roller while rotating the metal roller. In this case, the application unit can apply the resin solution while relatively moving in the direction of the rotation axis of the metal roller.

In the method for manufacturing a coated pressure roller of the present invention, the heat treatment of the resin solution can be performed by heating the metal roller using a heating mechanism of the metal roller.

The method for repairing the coated pressure roller of the present invention is to heat and press the polyimide film and the metal foil by overlapping the polyimide film and the metal foil and continuously passing between a pair of pressure rollers Next, the method for repairing the coated pressure roller used when manufacturing the metal-clad laminate. Furthermore, the method for repairing the coated pressure roller of the present invention is characterized in that the coated pressure roller includes a metal roller and a coating layer, the coating layer covers the surface of the metal roller in the circumferential direction, and the coating The repair methods of the pressure roller include: A step of coating a resin solution of polyimide or a precursor of polyimide on at least a part of the surface of the coating layer; and The step of heat-treating the resin solution is completed on the coated pressure roller. [Effect of invention]

According to the present invention, it is possible to manufacture a metal-clad laminate in which the polyimide film fills the unevenness of the surface of the metal foil without unevenness, and the polyimide film and the metal foil are firmly adhered. By using the metal-clad laminate manufactured in the above manner as a circuit board material such as FPC, a circuit board excellent in the adhesion between the fine wiring and the insulating resin layer can be manufactured. Therefore, the present invention can improve the yield and reliability of circuit boards and electronic products using the circuit boards. In addition, when a metal roller is used as the pressure roller, the pressure on the pressing surface is likely to become uneven due to uneven thickness of the polyimide film and variations in the diameter of the metal roller in the width direction. At this time, there may be a problem that the polyimide film does not sufficiently fill the irregularities on the surface of the metal foil at the places where the pressure is low. In the method of the present invention, by using a film-like cushioning material, the pressure unevenness is made uniform, and it is possible to produce a polyimide film in which the unevenness of the surface of the metal foil is sufficiently filled and firmly adhered over the entire surface. Metal laminate.

Hereinafter, embodiments of the present invention will be described with appropriate reference to the drawings. The manufacturing method of the metal-clad laminate of the present invention is to laminate the polyimide film and the metal foil by overlapping the polyimide film and the metal foil and continuously passing between a pair of pressure rollers, and to heat and pressure-bond the polyimide film and the metal foil Metal laminate. At this time, thermal compression bonding is performed in a state where at least one of the pressure rollers of the pair of pressure rollers is covered with a film-shaped buffer material, and the film-shaped buffer material can move in synchronization with the pressure roller . Here, the film-like cushioning material includes a non-thermoplastic polyimide layer containing non-thermoplastic polyimide. In addition, the so-called "non-thermoplastic polyimide" generally refers to polyimide that softens without heating even when heated, and in the present invention refers to the use of a dynamic viscoelasticity measuring device (dynamic mechanical thermal analysis) (Dynamic Mechanical Thermal Analyzer, DMA)) Polyimide with a storage elasticity coefficient at 30°C of 1.0×10 ⁹ Pa or more and a storage elasticity coefficient at 300°C of 3.0×10 ⁸ Pa or more. The "thermoplastic polyimide" generally refers to a polyimide whose glass transition temperature (Tg) can be clearly confirmed. In the present invention, it refers to 30°C measured using a dynamic viscoelasticity measuring device (DMA) Polyimide with a storage elasticity coefficient of 1.0×10 ⁹ Pa or more and a storage elasticity coefficient of 320° C. of less than 3.0×10 ⁸ Pa.

Hereinafter, preferred embodiments of the "film-like cushioning material" used in the method of the present invention will be described with reference to the first to third embodiments.

[First embodiment] FIG. 1 is an explanatory diagram of a method of manufacturing a metal-clad laminate according to a first embodiment of the present invention. Fig. 2 is an enlarged cross-sectional view of a main part of the coated pressure roller used in the method. In the present embodiment, the polyimide film 10 and the metal foil 20 are heated and pressed by overlapping the polyimide film 10 and the metal foil 20 and continuously passing between the pair of pressure rollers 30 and 40. Then, the metal-clad laminate 100 is manufactured. Furthermore, the film-shaped cushioning material forms a coating layer 50 that covers the surface of the pressure roller 30 in the circumferential direction. That is, the one-side pressure roller 30 is a coating pressure roller having a coating layer 50. Therefore, in this embodiment, thermal compression bonding is performed in a state where the pressing surface of at least one side of the pressure roller 30 of the pair of pressure rollers 30 and 40 is covered by the coating layer 50 as a film-shaped buffer material. The coating layer 50 can move in synchronization with the pressure roller 30. Here, the “pressing surface” of the pressure roller 30 refers to a portion of the surface of the rotating pressure roller 30 that presses the polyimide film 10 toward the metal foil 20 side (the other pressure roller 40 side). The pressing surfaces are sequentially replaced by the rotation of the pressure roller 30. In addition, the portion where the coating layer 50 is pressure-contacted with the polyimide film 10 is also sequentially replaced in synchronization with the rotation of the pressure roller 30. In addition, the arrow in FIG. 1 shows the conveyance direction or the rotation direction, and illustrations of the unwinding roller, the winding roller, the guide roller, and the like are omitted. The pair of pressure rollers 30 and 40 each include a heating mechanism (not shown).

In FIG. 1, the other pressure roller 40 is a metal roller that does not have the coating layer 50. Both the pressure roller 30 and the pressure roller 40 may be coated pressure rollers that have the coating layer 50. The use of both the pressure roller 30 and the pressure roller 40 as coating pressure rollers is effective for reducing the pressure deviation at the time of thermal compression bonding in the roller width direction. On the other hand, in order to efficiently conduct heat to the crimping site, it is effective to make one of the pressure roller 30 and the pressure roller 40 as a coated pressure roller and the other roller without the coating layer 50 Metal roll. In this case, as shown in FIG. 1, it is preferable that the pressing roller 40 pressed from the metal foil 20 side is made of a metal roller that does not have the coating layer 50. By arranging metal rollers on the metal foil 20 side, heat can be more efficiently conducted to the crimping site. That is, by directly contacting the metal pressure roller 40 and the metal foil 20, heat can be quickly transferred from the pressure roller 40 heated by a heating mechanism (not shown) to the metal foil 20 having a high thermal conductivity. Since the pressure-bonded portion with the polyimide film 10 is high, the efficiency of thermal compression bonding becomes high, and the adhesion between the polyimide film 10 and the metal foil 20 becomes good.

<Coated Press Roller> As shown in FIG. 2, the pressure roller 30 includes a metal roller 31 as a core, an adhesive layer 33 covering the periphery of the metal roller 31, and a metal layer covered by the adhesive layer 33. The polyimide coating layer 35 of the roller 31. The adhesive layer 33 and the polyimide coating layer 35 constitute the coating layer 50. In addition, the adhesive layer 33 may not be provided.

The adhesive layer 33 preferably contains a polyimide-based adhesive. The adhesive layer 33 ensures the adhesion between the metal roller 31 and the polyimide coating layer 35. In addition, the polyimide-based adhesive refers to an adhesive having an amide imide bond, and for example, includes siloxane polyimide, polyether amide imide, and the like.

On the other hand, the polyimide coating layer 35 preferably contains non-thermoplastic polyimide. By forming the polyimide coating layer 35 in direct contact with the polyimide film 10 from a non-thermoplastic polyimide, it can be prevented that the polyimide coating layer 35 is partially thermally welded to the polyimide film 10 The appearance of abnormal appearance such as wrinkles and smudges. The polyimide constituting the polyimide coating layer 35 is preferably, for example, a polyimide having heat resistance with a glass transition temperature (Tg) of 300° C. or higher. By using polyimide having a Tg of 300° C. or higher, it is possible to avoid deformation or damage due to heating during thermocompression bonding, thereby improving the durability of the coating layer 50. In addition, from the same viewpoint, the Tg of the polyimide constituting the polyimide coating layer 35 is preferably higher than the Tg of the thermoplastic polyimide (described later) constituting a part of the polyimide film 10 by, for example, 10 ℃ above. In addition, from the viewpoint of alleviating thermal shock to the polyimide film 10 during thermocompression bonding, the polyimide coating layer 35 preferably has a thermal conductivity of less than 0.2 W/m·K.

In addition, in order to suppress the dimensional change due to the temperature change during thermocompression bonding and to ensure the followability of the transferred polyimide film 10, the thermal expansion coefficient E of the polyimide coating layer 35 constituting the coating layer 50 is preferably The coefficient of thermal expansion E1 of the entire polyimide film 10 described later has a relationship of, for example, 0.5×E≦E1≦1.5×E.

The thickness of the coating layer 50 (in this embodiment, the total thickness of the adhesive layer 33 and the polyimide coating layer 35) is not particularly limited, but for example, it is preferably in the range of 1 μm to 200 μm, and more preferably 10 Within the range of μm～100 μm. In order to efficiently conduct heat, the upper limit of the thickness is preferably 200 μm or less. In addition, as described below, when a resin solution of polyimide or a polyimide precursor is applied to the surface of the metal roller 31 and then heat-treated to form the coating layer 50, in order to make the coating layer 50 It is easy to form, more preferably 100 μm or less. Furthermore, in order to prevent temperature variations in the width direction of the metal roller 31, the thickness of the coating layer 50 is preferably 25 μm or less. In order to withstand repeated use, the lower limit of the thickness is preferably 1 μm or more, and more preferably 5 μm or more.

The coating layer 50 as a film-shaped cushioning material has the effect of easing the bias of the pressure at the time of thermocompression bonding and distributing the pressure equally, and has the effect of uniformly bonding the polyimide film 10 and the metal foil 20. Therefore, it is possible to manufacture the metal-clad laminate 100 in which the polyimide film 10 fills the unevenness of the surface of the metal foil 20 without unevenness, and the polyimide film 10 and the metal foil 20 are firmly adhered.

The coating layer 50 may preferably use a film containing at least non-thermoplastic polyimide, or may be a film containing only non-thermoplastic polyimide, and may contain other components as necessary. Specifically, other components include resins other than non-thermoplastic polyimide, various additives for improving various characteristics of the coating layer 50, and the like. In addition, non-thermoplastic polyimide can also be used in combination. In addition, fillers and the like may also be contained.

<Manufacturing method of coated pressure roller> The pressure roller 30 having a metal roller 31 and a coating layer 50 covering the surface of the metal roller 31 in the circumferential direction can be manufactured by a method including the following steps a and b, for example: a) The step of coating the resin solution of polyimide or polyimide precursor on the surface of the metal roller 31; b) The step of forming the coating layer 50 by completing the heat treatment of the resin solution on the metal roller 31.

In step a, it is preferable to apply a resin solution to the surface of the metal roller 31 while rotating it. As a method of applying the resin solution to the metal roller 31, for example, a coating unit such as a coater or a sprayer may be used, or it may be lifted after the metal roller 31 is immersed in the resin solution The dipping method of pulling the metal roll 31. When applying a resin solution to the surface of the metal roller 31 using a coating unit such as a coater or a sprayer, it is more preferable to apply the coating unit while relatively moving in the direction of the rotation axis of the metal roller 31 Resin solution. For example, as shown in FIG. 3, it is preferable to bring the discharge port of the coating unit 61 close to or in contact with the surface of the metal roller 31 and rotate the metal roller 31 while rotating the discharge port along the metal roller 31 The axis direction is relatively moved, and the resin solution 63 is continuously supplied to the surface of the metal roller 31 from the discharge port. Here, the term “relatively moving the discharge port in the direction of the rotation axis of the metal roller 31 ”refers to moving from one end to the other end of the rotating metal roller 31. Therefore, the resin solution 63 is applied spirally on the surface of the metal roller 31. In addition, after the resin solution 63 is applied to the surface of the metal roller 31, the metal roller 31 may be rotated before the start of the heat treatment for the purpose of making the thickness of the resin solution 63 uniform.

In step b, heat treatment is performed by heating on the metal roller 31 to form the coating layer 50. Heating The metal roller 31 may be placed in an oven to heat the entire body, or may be heated by blowing hot air on the surface of the metal roller 31 with a heater. In addition, the heating mechanism (not shown) of the metal roller 31 itself may be used to heat from the inside of the metal roller 31.

The heat treatment conditions differ depending on the chemical structure, thickness, area, and type of solvent of the resin solution 63 constituting the polyimide constituting the coating layer 50, and the maximum temperature is preferably within a range of 300°C or more and 500°C or less. In addition, if rapid heating is performed, gas outgassing when the temperature rises may occur, and bubbles may be generated. Therefore, it is preferable to take, for example, 30 minutes or more to increase the temperature to the maximum temperature.

When the coating layer 50 is composed of a plurality of polyimide layers, the steps a and b may be repeated, or the step a may be carried out in batches after the step a is repeated a predetermined number of times.

<Repair method of coated pressure roller> Regarding the coating layer 50, when the coating layer 50 is formed on the surface of the metal roller 31, defects such as bubbles, surface roughness, and adhesion of foreign matter may occur. In addition, the use of the pressure roller 30 having the coating layer 50, that is, the manufacture of the metal-clad laminate 100 also causes the same defects. When a defect has occurred in the coating layer 50 of the pressing roller 30, the defective part can be repaired. The repair of the pressure roller 30 with the coating layer 50 may include the following steps c and d, for example: c) a step of coating a resin solution of polyimide or a precursor of polyimide on at least a part of the surface of the coating layer 50 (for example, the defect portion and its surroundings); d) The step of heat-treating the resin solution is completed on the pressure roller 30 having the coating layer 50.

In step c, for example, as shown in FIG. 4, the discharge port of the coating unit 61 such as a syringe is brought close to or in contact with the surface of the metal roller 31, and the resin solution 63 is partially applied to the metal roller from the discharge port 31's surface.

The heat treatment in step d can be carried out in the same manner as in step b in the method of manufacturing the coated pressure roller.

In addition, before step c, step c may be performed after removing the defect or the coating layer 50 of the defect and its periphery from the surface of the metal roller 31. In addition, after the heat treatment in step d is completed, a treatment for smoothing the surface of the coating layer 50 may be performed, for example, polishing by an abrasive material.

<Polyimide film> The polyimide film 10 that is thermocompression-bonded with the metal foil 20 includes a single-layer or multi-layer polyimide layer, and may further include any layer other than the polyimide layer. In this case, it is preferable that at least one layer is a non-thermoplastic polyimide layer, and at least the surface on the side that is thermocompression-bonded with the metal foil 20 is a thermoplastic polyimide layer. In this case, in order to ensure the adhesion to the metal foil 20, the glass transition temperature (Tg) of the thermoplastic polyimide is preferably in the range of 200°C to 350°C, and more preferably in the range of 280°C to 320°C Inside.

From the viewpoint of achieving a thinner circuit board such as an FPC obtained by processing the metal-clad laminate 100, the thickness of the polyimide film 10 is preferably, for example, in the range of 1 μm to 150 μm, and more preferably 2 μm ~100 μm. If the thickness of the polyimide film 10 is less than 1 μm, functions such as electrical insulation may be impaired. If the thickness of the polyimide film 10 exceeds 150 μm, it is difficult to reduce the thickness of the circuit board such as FPC.

The thermal expansion coefficient of the entire polyimide film 10 is preferably as close as possible to the thermal expansion coefficient of the metal foil 20. By making the thermal expansion coefficient of the polyimide film 10 close to the thermal expansion coefficient of the metal foil 20, it is possible to suppress the occurrence of warpage and the like in the FPC processing process. From such a viewpoint, in the metal-clad laminate 100, it is preferable that the thermal expansion coefficient E1 of the entire polyimide film 10 and the thermal expansion coefficient E2 of the metal foil 20 have a relationship of, for example, 0.7×E1≦E2≦1.1×E1.

In addition, the polyimide film 10 may be in the form of a laminated structure including an arbitrary layer in addition to the polyimide layer. As an arbitrary layer, a base material, a release film, etc. are mentioned, for example. As a preferred embodiment of the polyimide film 10, as shown in FIG. 5, polyimide having a laminated structure including a base material 71 and a polyimide layer 73 formed on the base material 71 in a laminated manner may be mentioned. Amine film 10A. Here, as the base material 71, for example, a metal foil such as copper foil can be mentioned. When the base material 71 is a copper foil, the polyimide film 10A is a single-sided CCL. By using a single-sided CCL as the polyimide film 10A, a double-sided CCL (double-sided copper-clad laminate) used in a double-sided circuit board capable of achieving high-density wiring can be manufactured, which is particularly advantageous. In addition, when a single-sided CCL is used as the polyimide film 10A, it is preferably arranged so that the pressure roller 30 having the coating layer 50 is pressed against the copper foil layer side of the single-sided CCL. The reason for this is that since the coating layer 50 with the pressure roller 30 interposed therebetween, it is possible to avoid applying excessive thermal history to the copper foil as the base material 71. In addition, by arranging the pressure roller 30 having the coating layer 50 to be pressure-bonded to the copper foil layer side of the single-sided CCL, the pressure roller 30 is prevented from being in close contact with the copper foil as the base material 71, and the transportability can be maintained. And it can prevent the small size defects of copper foil.

In addition, the single-sided CCL as the polyimide film 10A is preferably a single-sided CCL manufactured by a casting method in which a polyimide or a polyimide precursor is used The applied resin solution is applied onto the base 71 and dried, and then subjected to heat treatment, thereby forming the polyimide layer 73. In addition, the polyimide layer 73 may be formed of only a single layer. In consideration of the adhesion and dimensional stability of the polyimide layer 73 and the copper foil, it is preferable to include multiple layers. In the case where the polyimide layer 73 is formed into multiple layers, other polyimide or polyimide containing different constituent components may be sequentially coated on the resin solution of the polyimide or polyimide precursor It is formed by a resin solution of an amine precursor. When the polyimide layer 73 includes multiple layers, the resin solution of the same configuration may be used twice or more. In addition, the single-sided CCL manufactured by the casting method is an advantageous embodiment having excellent dimensional stability. Furthermore, by arranging the coating layer 50 only on the copper foil layer side of the single-sided CCL, the dimensional change rate during thermocompression bonding can be reduced Control is lower. In addition, when a single-sided CCL is used as the polyimide film 10A, the obtained metal-clad laminate 100A is a double-sided CCL (double-sided copper-clad laminate).

When the polyimide layer 73 of the single-sided CCL is a laminated structure of a non-thermoplastic polyimide layer and a thermoplastic polyimide layer, it is preferably a non-thermoplastic polyimide layer and a thermoplastic polyimide The thickness ratio of the layer (non-thermoplastic polyimide layer/thermoplastic polyimide layer) is in the range of 1.5 to 10.0. If the value of the ratio is less than 1.5, the non-thermoplastic polyimide layer becomes thinner relative to the entire polyimide layer 73, so the rate of dimensional change during etching of the copper foil tends to increase, if it exceeds 10.0 Since the thermoplastic polyimide layer becomes thinner, the reliability of adhesion between the polyimide layer 73 and the copper foil tends to decrease.

<Metal foil> Examples of the metal of the metal foil 20 include copper, aluminum, stainless steel, iron, silver, palladium, nickel, chromium, molybdenum, tungsten, zirconium, gold, cobalt, titanium, tantalum, zinc, lead, tin, and silicon. Metals such as bismuth, indium, or alloys of these. In terms of conductivity, a metal foil of copper or copper alloy is particularly preferred. In order to continuously produce the metal-clad laminate 100 and the metal-clad laminate 100A, a long metal foil 20 in which a metal foil of a predetermined thickness is wound into a roll shape may be used.

The surface roughness of the surface of the metal foil 20 directly contacting the polyimide film 10 is preferably 0.1 μm to 7 μm in terms of Rz, for example. The reason is that if it is within the above range, the adhesion to the polyimide film 10 is sufficiently good. Furthermore, if Rz is 0.3-3.0 micrometers, it is more preferable. Here, Rz represents the ten-point average roughness specified in Japanese Industrial Standards (JIS) B 0601 (1994).

<Thermal compression conditions> The heating method of the pressure roller 30 and the pressure roller 40 is not particularly limited as long as it can be heated at a predetermined temperature, and examples thereof include a heat medium circulation method, a hot air heating method, and a dielectric heating method. The pressurization method is also not particularly limited as long as a predetermined pressure can be applied, and examples thereof include a hydraulic method, a pneumatic method, and a gap pressure method.

The pressure during thermal compression bonding of the polyimide film 10 and the metal foil 20 by the pressure roller 30 and the pressure roller 40 is not particularly limited, but for example, it is preferably in the range of 0.1 Mpa to 50 MPa.

In addition, the temperature during thermocompression bonding is preferably, for example, 280°C or higher, and more preferably in the range of 300°C to 400°C.

[Second Embodiment] 6 is an explanatory diagram of a method of manufacturing a metal-clad laminate according to a second embodiment of the present invention. In this embodiment, the film-shaped buffer material is formed in a ring shape. That is, in this embodiment, the ring-shaped polyimide film 50A is disposed on the outer circumference of at least one side of the pressure roller 40A of the pair of metal pressure rollers 40A and 40B, and this is used as a film-shaped buffer material. Here, "ring-shaped" also includes a cylindrical shape. In FIG. 6, the film-shaped cushioning material is not arranged on the side of the other pressure roller 40B, and it is also possible to perform thermocompression bonding in a state where both the pressure roller 40A and the pressure roller 40B are covered with the film-shaped cushioning material.

The ring-shaped polyimide film 50A is formed to have an inner diameter larger than the outer diameter of the pressure roller 40A, and is formed to be rotatable by the one-side pressure roller 40A, the guide roller 80A, and the guide roller 80B. By rotating the ring-shaped polyimide film 50A in the same direction as the rotation direction of the pressure roller 40A, the pressure roller 40A can be coated with the ring-shaped polyimide film 50A that can move in synchronization with the pressure roller 40A Thermal compression bonding in the state of the pressing surface. In addition, the guide roller is not limited to two, and one or more than three may be arranged.

As described above, since the inner diameter of the ring-shaped polyimide film 50A is larger than the outer diameter of the pressure roller 40A, the ring-shaped polyimide film 50A is not fixed to the pressure roller 40A. Polyimide has hygroscopic properties, and the moisture contained in the ring-shaped polyimide film 50A rapidly evaporates during thermal compression bonding, which may cause the appearance of the metal-clad laminate 100 to be poor. When the inner diameter of the ring-shaped polyimide film 50A is sufficiently larger than the outer diameter of the pressure roller 40A, the ring-shaped polyimide film 50A can be coated with a coating before reaching the thermocompression bonding surface Since a part of the pressing roller 40A is brought into contact for preheating, the moisture contained in the ring-shaped polyimide film 50A can be reduced. The time during which the ring-shaped polyimide film 50A is in contact with the pressure roller 40A is preferably 1 second or more.

The thickness of the cyclic polyimide film 50A is not particularly limited. For example, it is preferably in the range of 1 μm to 200 μm, and more preferably in the range of 10 μm to 100 μm. The upper limit of the thickness is preferably 200 μm or less in order to efficiently conduct heat, and preferably 25 μm or less in order to prevent temperature deviation in the width direction of the pressing roller 40A. The lower limit of the thickness is preferably 1 μm or more in order to withstand repeated use, and more preferably 5 μm or more.

The ring-shaped polyimide film 50A can be manufactured, for example, by applying a resin solution of polyimide or polyimide precursor to the surface of a cylindrical or cylindrical release material, and releasing After the heat treatment of the resin solution is completed on the material, it is peeled off from the release material. The coating method or heat treatment conditions of the resin solution to the release material can be implemented in accordance with steps a and b in the manufacturing method of the coated pressure roller.

The ring-shaped polyimide film 50A may include a single layer or multiple layers of polyimide layers. In this case, it is preferable that at least one layer is a non-thermoplastic polyimide, and at least the surface (inner peripheral surface) on the side in contact with the pressure roller 40A is a thermoplastic polyimide layer. That is, for the ring-shaped polyimide film 50A, a thermoplastic polyimide layer with high adhesiveness can be used to make the surface of the metal pressure roller 40A easily adhere to each other.

On the other hand, in the ring-shaped polyimide film 50A, the surface (outer peripheral surface) on the side directly in contact with the polyimide film 10 preferably contains non-thermoplastic polyimide. By forming the surface directly in contact with the polyimide film 10 from the non-thermoplastic polyimide layer, it is possible to prevent wrinkles and stains caused by the partial thermal fusion of the ring-shaped polyimide film 50A to the polyimide film 10 The appearance of abnormalities such as traces. The polyimide constituting the non-thermoplastic polyimide layer in the cyclic polyimide film 50A is preferably, for example, a polyimide having heat resistance with a glass transition temperature (Tg) of 300° C. or higher. By using polyimide having a Tg of 300° C. or higher, it is possible to avoid deformation or damage due to heating during thermocompression bonding, thereby improving the durability of the ring-shaped polyimide film 50A. In addition, from the same viewpoint, the Tg of the polyimide constituting the non-thermoplastic polyimide layer in the cyclic polyimide film 50A is preferably higher than the thermoplastic polyimide constituting part of the polyimide film 10. The Tg of imine (described later) is, for example, 10°C or higher.

In addition, in order to suppress the dimensional change caused by the temperature change during thermocompression bonding and ensure precise followability of the transferred polyimide film 10, the thermal expansion coefficient E3 of the entire ring-shaped polyimide film 50A is preferably relatively The coefficient of thermal expansion E1 of the entire polyimide film 10 described later is, for example, a relationship of 0.5×E3≦E1≦1.5×E3.

In addition, as the ring-shaped polyimide film 50A, a ring-shaped metal-clad laminate such as a ring-shaped CCL may also be used. By using the ring-shaped metal-clad laminate as the ring-shaped polyimide film 50A, the operability is improved and the durability can be improved. The ring-shaped metal-clad laminate used as the ring-shaped polyimide film 50A is preferably a ring-shaped metal-clad laminate manufactured by a casting method from the viewpoint of durability.

The ring-shaped polyimide film 50A, which is a film-shaped cushioning material, has the effect of easing and evenly distributing the pressure during thermocompression bonding, and has the effect of uniformly bonding the polyimide film 10 and the metal foil 20.

The other configurations and effects of this embodiment are the same as those of the first embodiment. In addition, as in the present embodiment, as a modification, as shown in FIG. 7, the metal-clad laminate 100A can be manufactured by using the polyimide film 10A having a laminated structure instead of the polyimide film 10.

The ring-shaped polyimide film 50A is preferably heated in advance before thermocompression bonding to reduce moisture. For example, the polyimide constituting the cyclic polyimide film 50A has hygroscopic characteristics, and the moisture contained therewith evaporates during thermocompression bonding, especially in the case of the polyimide film 10A, there is a concern This leads to poor appearance of the copper foil on the single-sided CCL side. When the ring-shaped polyimide film 50A is used during thermocompression bonding, the ring-shaped polyimide is made to allow time for contact with the pressure roller 40A before reaching the thermocompression bonding surface by increasing the insertion angle or the like. The imine film 50A contacts so as to cover a part of the pressure roller 40A, so that the ring-shaped polyimide film 50A can be heated in advance. At this time, the time during which the ring-shaped polyimide film 50A is in contact with the pressure roller 40A is preferably 1 second or more.

[Third Embodiment] 8 is an explanatory diagram of a method of manufacturing a metal-clad laminate according to a third embodiment of the present invention. In this embodiment, the film-shaped cushioning material is formed into a long strip and is configured to be transported in a roll-to-roll manner. That is, in the present embodiment, the long polyimide film 50B is disposed between at least one of the pair of metal pressure rollers 40A and the pressure roller 40B and the polyimide film 10. And use it as a film-like cushioning material. In FIG. 8, the film-shaped cushioning material is not arranged on the side of the other pressure roller 40B, and it is also possible to perform thermocompression bonding in a state where both the pressure roller 40A and the pressure roller 40B are covered with the film-shaped cushioning material.

The long-shaped polyimide film 50B is formed so as to be transportable by the pressure roller 40A, the unwinding roller 90A, and the winding roller 90B. By transporting the long-shaped polyimide film 50B in the same direction as the rotation direction of the pressure roller 40A, the long-type polyimide film 50B that can move in synchronization with the pressure roller 40A can be coated and pressurized Thermal compression bonding is performed in the state of the pressing surface of the roller 40A. In addition, in order to adjust the angle at the time of contact with the pressure roller 40A and the angle at the time of separation, one or more guide rollers may be arbitrarily provided.

As described above, the long polyimide film 50B is not fixed to the pressure roller 40A. As in the case of the annular polyimide film 50A of the second embodiment, the long polyimide film 50B transported at the same speed as the pressure roller 40A can reach the thermocompression bonding surface before reaching Pre-heating is performed by contacting to cover a part of the pressure roller 40A, so that the moisture contained in the long-shaped polyimide film 50B can be reduced. The time during which the long-shaped polyimide film 50B is in contact with the pressure roller 40A is preferably 1 second or more.

The thickness of the long-shaped polyimide film 50B is not particularly limited. For example, it is preferably in the range of 1 μm to 200 μm, and more preferably in the range of 10 μm to 100 μm. The upper limit of the thickness is preferably 200 μm or less in order to efficiently conduct heat, and preferably 25 μm or less in order to prevent temperature deviation in the width direction of the pressing roller 40A. The lower limit of the thickness is preferably 1 μm or more in order to withstand repeated use, and more preferably 5 μm or more.

The elongated polyimide film 50B may include a single layer or multiple layers of polyimide layers. In this case, it is preferable that at least one layer is a non-thermoplastic polyimide, and at least the surface on the side in contact with the pressure roller 40A is a thermoplastic polyimide layer. That is, the long-shaped polyimide film 50B can use a thermoplastic polyimide layer with high adhesiveness to make it easily adhere to the surface of the metal pressure roller 40A.

On the other hand, in the elongated polyimide film 50B, the surface on the side directly in contact with the polyimide film 10 preferably contains non-thermoplastic polyimide. By forming a surface directly in contact with the polyimide film 10 from the non-thermoplastic polyimide layer, it is possible to prevent wrinkles caused by the partial fusion of the elongated polyimide film 50B to the polyimide film 10, Abnormal appearance such as smudges. The polyimide constituting the non-thermoplastic polyimide layer in the long polyimide film 50B is preferably, for example, a polyimide having heat resistance with a glass transition temperature (Tg) of 300° C. or higher. By using a polyimide having a Tg of 300° C. or higher, it is possible to avoid deformation or damage due to heating during thermocompression bonding, thereby improving the durability of the long polyimide film 50B. In addition, from the same viewpoint, the Tg of the polyimide constituting the non-thermoplastic polyimide layer in the long polyimide film 50B is preferably higher than that of the thermoplastic polymer constituting part of the polyimide film 10 The Tg of acetylenimine (described later) is, for example, 10°C or higher.

In addition, in order to suppress dimensional changes due to temperature changes during thermocompression bonding and to ensure precise followability of the polyimide film 10 to be transported, the thermal expansion coefficient E4 of the entire long polyimide film 50B is preferably The coefficient of thermal expansion E1 of the entire polyimide film 10 described later has a relationship of, for example, 0.5×E4≦E1≦1.3×E4.

As the long-length polyimide film 50B, for example, Kapton V (trade name) manufactured by Toray DuPont (Toray DuPont) or UPILEX S manufactured by Ube Kosei Corporation can be used. (Brand name) and other commercially available polyimide membranes.

In addition, as the long polyimide film 50B, a long metal-clad laminate such as a long CCL can also be used. By using an elongated metal-clad laminate as the elongated polyimide film 50B, operability is improved, and durability can be improved. The long metal-clad laminate used as the long polyimide film 50B is preferably a long metal-clad laminate produced by a casting method from the viewpoint of durability and thickness uniformity.

The elongated polyimide film 50B as a film-shaped buffer material has the effect of easing and evenly distributing the pressure during thermocompression bonding, and has the effect of uniformly adhering the polyimide film 10 and the metal foil 20.

The other configurations and effects of this embodiment are the same as those of the first and second embodiments. In addition, as in the present embodiment, as a modification, as shown in FIG. 9, the metal-clad laminate 100A can be manufactured by using the polyimide film 10A having a laminated structure instead of the polyimide film 10.

The elongated polyimide film 50B is preferably heated in advance before thermocompression bonding to reduce moisture. For example, the polyimide constituting the long polyimide film 50B has hygroscopic characteristics, and the moisture contained therewith evaporates during thermocompression bonding, especially in the case of the polyimide film 10A. The copper foil on the single-sided CCL side may have a poor appearance. In the case of using the long polyimide film 50B at the time of thermocompression bonding, by increasing the insertion angle or the like to allow time for contact with the pressure roller 40A before reaching the thermocompression bonding surface, the long strip The polyimide film 50B is in contact so as to cover a part of the pressure roller 40A, so that the long polyimide film 50B can be heated in advance. At this time, the time during which the long polyimide film 50B is in contact with the pressure roller 40A is preferably 1 second or more.

As described above, in the metal-clad laminate 100 and the metal-clad laminate 100A obtained in the first to third embodiments, the polyimide film 10 and the polyimide film 10A affect the metal foil 20 uniformly. The irregularities on the surface are filled, and the polyimide film 10, the polyimide film 10A, and the metal foil 20 are firmly adhered. The adhesion strength (peel strength) of the polyimide film 10, the polyimide film 10A and the metal foil 20 can be determined by the raw material monomer of the polyimide film constituting the polyimide film 10 and the polyimide film 10A The types or ratios, heat treatment conditions, etc. are controlled.

[Polyimide] Next, in the first to third embodiments described above, the polyimide film 10, the polyimide film 10A, the coating layer 50, the ring-shaped polyimide film 50A, or the elongated polyimide are configured Polyimide of a part or whole of the amine film 50B will be described. Polyimide is produced by polyimide acidation as a precursor of polyimide and can be produced by reacting a specific acid anhydride with a diamine compound. Therefore, polyacrylic acid can be understood by explaining the acid anhydride and the diamine compound Specific examples of imines. In addition, when referring to polyimide in the present invention, it means a resin containing a polymer having an imide group in the molecular structure. In addition to polyimide, there are polyimide, imide, and polyether imide. Imine, polyester amide imine, polysiloxane oxamide imide, polybenzimidazole amide imide, etc.

Regarding the diamine compound as the raw material of the polyimide, an aromatic diamine compound, an aliphatic diamine compound, etc. can be used, and for example, an aromatic diamine compound represented by NH ₂ -Ar1-NH ₂ can be cited as a preferred compound . Here, Ar1 is selected from the group represented by the following formula, the substitution position of the amino group is arbitrary, and it is preferably the p, p'position. Ar1 may further have a substituent, preferably without a substituent, or in the case of a substituent, the substituent may be a lower alkyl group or a lower alkoxy group having 1 to 6 carbon atoms. Only one type of these aromatic diamine compounds may be used, or two or more types may be used in combination.

[Chemical 1]

The acid anhydride reacted with the diamine compound is preferably an aromatic tetracarboxylic acid anhydride in terms of ease of synthesis of polyamic acid. The aromatic tetracarboxylic anhydride is not particularly limited, and examples thereof include compounds represented by O(CO) ₂ Ar2(CO) ₂ O as preferred compounds. Here, Ar2 is preferably a tetravalent aromatic group represented by the following formula, and the substitution position of the acid anhydride group [(CO) ₂ O] is arbitrary, and is preferably a symmetrical position. Ar2 may further have a substituent, and preferably has no substituent, or in the case of having a substituent, the substituent may be a lower alkyl group having 1 to 6 carbon atoms.

[Chem 2]

Polyimide film 10, polyimide film 10A, coating layer 50, ring-shaped polyimide film 50A, elongated polyimide film 50B may be a thermoplastic polyimide layer and a non-thermoplastic polyimide Since the multilayer structure of the imine layer, preferred examples of the acid anhydride and the diamine compound used for each of the thermoplastic polyimide and the non-thermoplastic polyimide will be described.

Thermoplastic polyimide: In the case where the polyimide is a thermoplastic polyimide, although not particularly limited, the diamino component as a raw material is preferably used, for example, containing 50 mol% or more selected from 3,4'-diaminodiphenyl Ether, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, 2,2-bis(4-(4-aminophenoxy)benzene More than one diamine compound in the group] propane. In addition, although not particularly limited, the acid anhydride component as a raw material is preferably used, for example, containing 50 mol% or more selected from pyromellitic dianhydride, 3,3',4,4'-biphenyltetracarboxylic diacid One or more of anhydride, benzophenone tetracarboxylic dianhydride, 3,3',4,4'-diphenyl sulfone tetracarboxylic dianhydride, 4,4'-oxydiphthalic anhydride Acid anhydride. By using a predetermined amount of the diamine compound or acid anhydride, the adhesiveness achieved by the thermoplastic polyimide can be fully exerted, and the thermocompression bonding property becomes high.

Non-thermoplastic polyimide: When the polyimide is a non-thermoplastic polyimide, although not particularly limited, the diamino component as a raw material is preferably used, for example, containing 60 mol% or more selected from 1,3-phenylenediamine , 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-bis (trifluoromethyl) benzidine, 3,4'-diaminodiphenyl ether Of diamine compounds. In addition, although not particularly limited, the acid anhydride component as a raw material is preferably used, for example, containing 60 mol% or more selected from pyromellitic dianhydride, 3,3′,4,4′-biphenyltetracarboxylic diacid One or more acid anhydrides in the anhydride. By using a predetermined amount of the diamine compound or acid anhydride, characteristics such as heat resistance and dimensional stability achieved by the non-thermoplastic polyimide can be exhibited.

Regarding the thermoplastic polyimide and the non-thermoplastic polyimide, the coefficient of thermal expansion, the coefficient of storage elasticity, the glass transition temperature, etc. can be controlled by selecting the types of the diamine compound and the acid anhydride, or the respective molar ratios.

In addition, when the thermoplastic polyimide and the non-thermoplastic polyimide have a plurality of structural units of polyimide, they may be present in the form of blocks or may be present randomly, preferably none Regularly exists.

Polyimide can be obtained, for example, by mixing the diamine compound and the acid anhydride in a solvent at an approximately equal molar ratio, and the reaction temperature is in the range of 0°C to 200°C, preferably 0°C to 100°C The reaction is carried out to obtain a resin solution of polyamic acid, which is further imidized. Examples of the solvent include N-methyl pyrrolidone (NMP), dimethyl formamide (DMF), dimethyl acetamide (DMAc), and dimethyl. Dimethyl sulfoxide (DMSO), dimethyl sulfate, cyclobutane, butyrolactone, cresol, phenol, halogenated phenol, cyclohexanone, dioxane, tetrahydrofuran, diethylene glycol dimethyl ether (diglyme) , Triethylene glycol dimethyl ether (triglyme), etc.

Generally, the synthesis of polyamide is carried out in a reaction vessel or the like. For example, a resin solution of polyamic acid is coated on an arbitrary substrate and dried to form a polyamic acid layer, and then the polyamic acid layer is imidized by heat treatment, thereby obtaining a polyimide Acetate layer. It can also be applied repeatedly on the formed polyamic acid layer or polyimide layer in a superimposed manner. Alternatively, the polyimide that has been previously imidized may be applied to the surface of an arbitrary substrate in the form of a solution dissolved in a solvent and dried to form a polyimide layer. When the polyimide film 10, the polyimide film 10A, the coating layer 50, the ring-shaped polyimide film 50A, and the elongated polyimide film 50B have a multilayer structure, it is preferable After the resin solution of the polyamic acid is applied to arbitrary substrates in portions and dried, the method of batching imidization is not limited to this. That is, a plurality of resin solutions of polyamic acid can be applied to any substrate in batches using a multi-layer mold or the like, and after drying it, the resin can be imidized in batches by heat treatment to form a plurality of Polyimide layer. In addition, a polyimide layer may be formed layer by layer by performing steps from coating and drying a plurality of polyamic acid resin solutions to imidate. When a plurality of polyimide layers are formed, these treatments can be combined arbitrarily.

The method for applying the polyimide solution or the polyamic acid resin solution to any substrate is not particularly limited. For example, a coating machine such as a corner wheel, mold, blade, die lip, etc. can be used. The representative coating unit performs coating. When forming a multi-layer polyimide layer, a method of repeatedly applying a polyimide solution (or a polyamic acid resin solution) to a substrate and drying it is preferred.

As the method of drying and heating the imidization treatment, for example, any method such as a batch processing method or a continuous processing method can be selected. The batch processing method is to apply a resin solution of polyamic acid to a long metal foil, wind the laminate into a roll without imidization, and set it to a predetermined value. The temperature is kept in a hot air drying furnace at a certain temperature for a certain period of time, and finally heat treatment is performed at a high temperature of 200° C. or higher, thereby completing the method of imidization. The continuous treatment method is to apply the resin solution of polyamide to the long metal foil, and then move it continuously in the drying furnace to ensure the prescribed heat treatment time, and finally perform heat treatment at a high temperature of 200°C or higher method. Among these methods, any method can be selected from the viewpoint of productivity, yield, etc. The heat treatment at a high temperature of 200° C. or higher is preferably under a reduced pressure environment, a reducing gas environment, or a reducing gas environment And under reduced pressure. In addition, the solvent of the polyacrylic acid resin is removed by the drying and heating in the amidation treatment step to be amidated. In this case, if the heat treatment is performed abruptly at a high temperature, a surface layer is formed on the surface of the resin. It is difficult for the solvent to evaporate or foam, so it is preferable to perform heat treatment while rising from a low temperature stage to a high temperature. In addition, in the heating amide imidization step, it is preferable to finally perform heat treatment at a temperature of 300°C to 400°C. [Example]

Hereinafter, examples will be shown to more specifically describe the features of the present invention. However, the scope of the present invention is not limited to the examples. In addition, in the following examples, unless otherwise specified, various measurements and evaluations are performed in the following manner.

[Coefficient of thermal expansion (CTE)] For a polyimide film with a size of 3 mm×20 mm, a thermomechanical analyzer (manufactured by Bruker, trade name: 4000SA) was used, and a constant temperature increase rate was applied while applying a load of 5.0 g After raising the temperature from 30°C to 265°C, and then maintaining the temperature for 10 minutes, it is cooled at a rate of 5°C/minute, and the average thermal expansion coefficient (linear thermal expansion coefficient) of 240°C to 100°C is obtained.

[Glass transition temperature (Tg)] The glass transition temperature is for a polyimide film with a size of 5 mm×20 mm, using a dynamic viscoelasticity measuring device (DMA: manufactured by UBM Co., Ltd., trade name: E4000F) at a heating rate of 4°C/min from 30°C The temperature was increased to 400°C, and the measurement was performed at a frequency of 11 Hz, and the temperature at which the elastic coefficient change (tan δ) was the largest was taken as the glass transition temperature.

[Determination of Viscosity] The viscosity was measured using an E-type viscometer (manufactured by Brookfield Corporation, trade name: DV-II+Pro) to measure the viscosity at 25°C. Set the rotation speed so that the torque is 10% to 90%, and read the value when the viscosity is stable after 2 minutes have elapsed since the start of the measurement.

[Peel strength] The peel strength was determined using a Tensilon tester (manufactured by Toyo Seiki Co., Ltd., trade name: Strograph VE-1D), and the metal on the conductor layer side was processed to width using double-sided tape The force at the time of peeling the metal wiring from the resin layer to the 180° direction at a speed of 50 mm/min.

[Filled state of thermocompression bonding surface] After etching the copper foil of the copper-clad laminate after thermocompression bonding over the entire width, the surface of the polyimide film is visually observed, and the person who has a uniform color on the whole surface is evaluated as good on the whole surface, and there will be a difference in color tone Of some people rated it as bad.

The abbreviations used in Examples and the like indicate the following compounds. BAPP: 2,2-bis[4-(4-aminophenoxy)phenyl]propane m-TB: 2,2'dimethyl-4,4'-diaminobiphenyl PMDA: pyromellitic dianhydride BPDA: 3,3',4,4'-biphenyltetracarboxylic dianhydride DMAc: N,N-dimethylacetamide

<Synthesis of Polyamic Acid Solution> (Synthesis Example 1) In a reaction vessel equipped with a thermocouple and a stirrer and capable of introducing nitrogen, 87.5 kg of DMAc was added, and 8.11 kg of BAPP was added to the reaction vessel Dissolve while stirring in the container. Next, put in 4.10 kg of PMDA. Then, stirring was continued for 3 hours to perform a polymerization reaction, and a resin solution 1 of polyamide a was obtained. Resin solution 1 (solid content: 12.5%) has a viscosity of 1,300 cps. In addition, the polyimide obtained by polyimidization of polyamic acid a is thermoplastic, and the coefficient of thermal expansion (CTE) of a 25 μm thick polyimide film formed of polyamic acid a is 55× 10 ^-6 /K, glass transition temperature is 320℃.

(Synthesis Example 2) In a reaction vessel equipped with a thermocouple and a stirrer and capable of introducing nitrogen, 212.5 kg of DMAc was added, and further 17.9 kg of m-TB was added to the reaction vessel and stirred while stirring in the vessel Dissolve. Next, put in 4.94 kg of BPDA and 14.7 kg of PMDA. Then, stirring was continued for 3 hours to perform a polymerization reaction, and a resin solution 2 of polyamic acid b was obtained. Resin solution 2 (solid content: 15%) has a viscosity of 26,500 cps. In addition, the polyimide obtained by polyimidization of polyamic acid b is thermoplastic, and the coefficient of thermal expansion (CTE) of a 25 μm thick polyimide film formed of polyamic acid b is 22× 10 ^-6 /K.

[Manufacture of Polyimide Coated Rollers] After rotating the metal roller provided with a heater inside, the resin solution 2 prepared in Synthesis Example 2 was applied to the surface of the metal roller using a coating machine, and then the metal roller was heated by the heater, by It took one hour to increase the temperature from room temperature to 360°C, and a polyimide-coated roller having a polyimide-coated layer having a predetermined thickness on the surface was obtained.

(Example 1) Using a long copper foil 1 (rolled copper foil, thickness: 12 μm, lateral width: 500 mm) as a base material, and using a die coater, the resin solution 1 prepared in Synthesis Example 1 was cured to a thickness after curing After being uniformly applied to the rough surface of the copper foil 1 so as to be 2.5 μm, it was heated and dried at 130° C. to remove the solvent. Next, on the coating surface side, the resin solution 2 prepared in Synthesis Example 2 was uniformly applied so that the thickness after curing became 20 μm, and was heated and dried at 120° C. to remove the solvent. Furthermore, on the coating surface side, the same resin solution 1 as the solution applied in the first layer was uniformly applied so that the thickness after curing became 2.5 μm, and the solution was heated and dried at 130° C. After removal, heat treatment was performed stepwise until 360° C. to obtain a single-sided copper-clad laminate 1a having a polyimide film with a thickness of 25 μm.

Using a heating and pressing device having a pair of pressure rollers, a polyimide coating roller 1 (thickness of the polyimide coating layer: 50 μm) was placed on the copper foil 1 side of the single-sided copper-clad laminate 1a. In addition, A long copper foil 2 (electrolytic copper foil, thickness: 12 μm, lateral width: 540 mm) is arranged on the polyimide layer side of the single-sided copper-clad laminate 1a, and further, the copper foil 2 is thermally pressed A metal roller is arranged on the opposite side of the surface. For these, while being transported via a guide roller, under a nitrogen atmosphere, the surface temperature of the roller: 300°C to 400°C, the linear pressure of the pressure roller: 38.6 to 115.8 kgf/cm, the transport speed: 4.0 m/min Under the condition of continuous thermal compression bonding, a double-sided copper-clad laminate 1b was obtained. The copper foil surface on the coated surface side of the obtained double-sided copper-clad laminate 1b had a good overall appearance, and the peel strength of the copper foil on the pressure contact side was 1.6 kN/m.

(Comparative example 1) A double-sided copper-clad laminate 1b' was obtained in the same manner as in Example 1, except that the two pressure rollers were made of metal. Part of the appearance of the copper foil surface on the coated surface side of the obtained double-sided copper-clad laminate 1b' was defective, and the peel strength of the copper foil on the pressure bonding side was 1.2 kN/m.

The results of Example 1 and Comparative Example 1 are shown in Table 1. [Table 1]

(Example 2) A double-sided copper-clad laminate 2b was obtained in the same manner as in Example 1, except that the polyimide coating roll 2 (thickness of the polyimide coating layer: 75 μm) was used. The copper foil surface on the coated surface side of the obtained double-sided copper-clad laminate 2b had a good overall appearance, and the peel strength of the copper foil on the pressure contact side was 1.6 kN/m.

(Example 3) The double-sided copper-clad laminate 3b was obtained in the same manner as in Example 1, except that the polyimide coating roll 3 (thickness of the polyimide coating layer: 25 μm) was used. The copper foil surface on the coated surface side of the obtained double-sided copper-clad laminate 3b had a good overall appearance, and the peel strength of the copper foil on the pressure contact side was 1.6 kN/m.

(Example 4) A double-sided copper-clad laminate 4b was obtained in the same manner as in Example 1, except that the polyimide coating roll 4 (thickness of the polyimide coating layer: 20 μm) was used. The copper foil surface on the coated surface side of the obtained double-sided copper-clad laminate 4b had a good overall appearance, and the peel strength of the copper foil on the pressure contact side was 1.6 kN/m.

(Example 5) A double-sided copper-clad laminate 5b was obtained in the same manner as in Example 1, except that the polyimide coating roll 5 (thickness of the polyimide coating layer: 15 μm) was used. The copper foil surface on the coated surface side of the obtained double-sided copper-clad laminate 5b had a good overall appearance, and the peel strength of the copper foil on the pressure contact side was 1.6 kN/m.

(Example 6) A double-sided copper-clad laminate 6b was obtained in the same manner as in Example 1, except that the polyimide coating roll 6 (thickness of the polyimide coating layer: 12 μm) was used. The copper foil surface on the coated surface side of the obtained double-sided copper-clad laminate 6b had a good overall appearance, and the peel strength of the copper foil on the pressure bonding side was 1.6 kN/m.

(Example 7) A double-sided copper-clad laminate 7b was obtained in the same manner as in Example 1, except that the polyimide coating roller 7 (thickness of the polyimide coating layer: 10 μm) was used. The copper foil surface on the coated surface side of the obtained double-sided copper-clad laminate 7b had a good overall appearance, and the peel strength of the copper foil on the pressure contact side was 1.6 kN/m.

(Example 8) A double-sided copper-clad laminate 8b was obtained in the same manner as in Example 1, except that the polyimide coating roll 8 (thickness of the polyimide coating layer: 8 μm) was used. The copper foil surface on the coated surface side of the obtained double-sided copper-clad laminate 8b had a good overall appearance, and the peel strength of the copper foil on the pressure contact side was 1.6 kN/m.

(Example 9) A double-sided copper-clad laminate 9b was obtained in the same manner as in Example 1, except that the polyimide coating roll 9 (thickness of the polyimide coating layer: 100 μm) was used. The copper foil surface on the coated surface side of the obtained double-sided copper-clad laminate 9b had a good overall appearance, and the peel strength of the copper foil on the pressure contact side was 1.6 kN/m.

(Example 10) Polyimide tape 10 (thickness: 20 μm, tensile strength: 400 MPa, tensile modulus of elasticity) was disposed on the copper foil 1 side of the single-sided copper-clad laminate 1a in Example 1 to remove moisture by preheating. : 9 GPa, seamless type (seamless type), instead of arranging the polyimide-coated roller 1, in the same manner as in Example 1, to obtain a double-sided copper-clad laminate 10b. The copper foil surface on the coated surface side of the obtained double-sided copper-clad laminate 10b had a good overall appearance, and the peel strength of the copper foil on the pressure contact side was 1.6 kN/m. In addition, the contact time between the polyimide belt 10 and the pressure roller was set to 2 seconds.

(Example 11) In the copper foil 1 side of the single-sided copper-clad laminate 1a in Example 1, a commercially available polyimide film 11 (thickness: 25 μm) in which moisture was removed by preheating was arranged instead of polyimide Except for this, the coating roll 1 was carried out in the same manner as in Example 1, and a double-sided copper-clad laminate 11b was obtained. The copper foil surface on the coated surface side of the obtained double-sided copper-clad laminate 11b had a good overall appearance, and the peel strength of the copper foil on the pressure contact side was 1.6 kN/m. In addition, the insertion angle of the polyimide film 11 to the pressure roller was set to 70°.

As described in detail above, according to the manufacturing method of the metal-clad laminate of the present embodiment, the polyimide film can be obtained to fill the irregularities of the surface of the metal foil without unevenness, and the polyimide film and the metal foil are strong Ground-clad metal-clad laminate. By using the metal-clad laminate manufactured in the above manner as a circuit board material such as FPC, a circuit board excellent in the adhesion between the fine wiring and the insulating resin layer can be manufactured. Therefore, according to the present invention, the yield and reliability of the circuit board and electronic products using the circuit board can be improved.

In the above, the embodiment of the present invention has been described in detail for the purpose of illustration, but the present invention is not restricted by the above embodiment.

10, 10A‧‧‧Polyimide film 20‧‧‧Metal foil 30‧‧‧Pressure roller (coated pressure roller) 31‧‧‧Metal roller 33‧‧‧adhesive layer 35‧‧‧Polyimide coating 40、40A、40B‧‧‧Pressure roller 50‧‧‧Coated layer 50A‧‧‧Circular Polyimide Film 50B‧‧‧long polyimide film 61‧‧‧Coating unit 63‧‧‧resin solution 71‧‧‧ Base material 73‧‧‧Polyimide layer 80A, 80B‧‧‧Guide roller 90A‧‧‧Roll-out roll 90B‧‧‧Winding roller 100、100A‧‧‧Metal-clad laminate

FIG. 1 is a diagram illustrating a method of manufacturing a metal-clad laminate according to a first embodiment of the present invention. FIG. 2 is a cross-sectional view showing the structure of the coating pressure roller. FIG. 3 is a diagram illustrating a method of manufacturing a covered pressure roller. FIG. 4 is a diagram illustrating a method of repairing a covered pressure roller. 5 is a diagram explaining a modification of the method of manufacturing the metal-clad laminate according to the first embodiment. 6 is a diagram illustrating a method of manufacturing a metal-clad laminate according to a second embodiment of the present invention. 7 is a diagram explaining a modification of the method of manufacturing the metal-clad laminate of the second embodiment. 8 is a diagram illustrating a method of manufacturing a metal-clad laminate according to a third embodiment of the present invention. 9 is a diagram explaining a modification of the method of manufacturing the metal-clad laminate according to the third embodiment.

10‧‧‧Polyimide film

20‧‧‧Metal foil

30‧‧‧Pressure roller (coated pressure roller)

40‧‧‧Pressure roller

50‧‧‧Coated layer

100‧‧‧Metal-clad laminate

Claims (15)

A method for manufacturing a metal-clad laminate, which is to heat-press the polyimide film and the metal foil by overlapping the polyimide film and the metal foil and continuously passing between a pair of pressing rollers Next, a method of manufacturing a metal-clad laminate, which is characterized by: Thermal compression bonding is performed in a state where at least one of the pressure rollers on one side of the pair of pressure rollers is covered with a film-shaped buffer material, and the film-shaped buffer material can be synchronized with the one-side pressure roller The film-like cushioning material includes a non-thermoplastic polyimide layer containing non-thermoplastic polyimide. The method for manufacturing a metal-clad laminate according to item 1 of the patent application range, wherein the film-shaped buffer material forms a coating layer that covers the surface of the one-side pressure roller in the circumferential direction. The method for manufacturing a metal-clad laminate according to item 2 of the patent application range, wherein the one-side pressure roller is a coated pressure roller having the coating layer, and the other pressure roller is a metal roller. The method for manufacturing a metal-clad laminate according to item 3 of the patent application scope, wherein the metal roller is arranged on the metal foil side. The method for manufacturing a metal-clad laminate according to item 1 of the patent application range, wherein the film-shaped buffer material is formed in a ring shape and is rotatable by the one-side pressure roller and the plurality of guide rollers Way to form. The method for manufacturing a metal-clad laminate as described in Item 1 of the patent application range, wherein the film-shaped buffer material is formed into a long strip and is conveyed in a roll-to-roll manner. The method for manufacturing a metal-clad laminate according to any one of claims 1 to 6, wherein the thickness of the film-shaped buffer material is within a range of 1 μm to 200 μm. The method for manufacturing a metal-clad laminate as described in any one of claims 1 to 6, wherein the polyimide film includes a single layer or multiple layers of polyimide layers, at least one of which is not Thermoplastic polyimide, and at least the surface on the side of the metal foil thermally press-bonded is a thermoplastic polyimide layer. The method for manufacturing a metal-clad laminate according to any one of claims 1 to 6, wherein the polyimide film is a polyimide film including a substrate and a laminate formed on the substrate The laminated structure of the amide imide layer. The method for manufacturing a metal-clad laminate as described in item 9 of the patent application range, wherein the base material is copper foil. A method for manufacturing a coated pressure roller, which is to heat and press the polyimide film and the metal foil by overlapping a polyimide film and a metal foil and passing continuously between a pair of pressure rollers Next, a method of manufacturing a coated pressing roller used when manufacturing a metal-clad laminate, the method of manufacturing the coated pressing roller is characterized by: The coated pressure roller includes a metal roller and a coating layer, the coating layer covers the surface of the metal roller in the circumferential direction, and the method of manufacturing the coated pressure roller includes: A step of applying a resin solution of polyimide or a precursor of polyimide on the surface of the metal roller; and The step of forming the coating layer by completing the heat treatment of the resin solution on the metal roller. The method for manufacturing a coated pressure roller according to claim 11 of the patent application, wherein the resin solution is applied to the surface of the metal roller while rotating the metal roller. The method for manufacturing a coated pressure roller according to claim 12 of the patent application range, wherein the coating solution is applied while the coating unit is relatively moved in the direction of the rotation axis of the metal roller. The method for manufacturing a coated pressure roller according to any one of claims 11 to 13, wherein the metal roller is heated by using the heating mechanism of the metal roller to perform The heat treatment of the resin solution is described. A repairing method of covering a pressure roller, which is to heat-press the polyimide film and the metal foil by overlapping the polyimide film and the metal foil and continuously passing between a pair of pressure rollers Next, a method for repairing a coated pressure roller used in manufacturing a metal-clad laminate is characterized by: The coated pressure roller includes a metal roller and a coating layer, the coating layer covers the surface of the metal roller in the circumferential direction, and the method of repairing the coated pressure roller includes: A step of coating a resin solution of polyimide or a precursor of polyimide on at least a part of the surface of the coating layer; and The step of heat-treating the resin solution is completed on the coated pressure roller.

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