KR100656247B1 - Method of surface modification of polyimide film using silanes coupling agent, manufacturing method of flexible copper clad laminate and its product thereby - Google Patents

Abstract

The present invention relates to a surface modification method of a polyimide film, a method for producing a flexible copper foil laminated film using the same, and a flexible copper foil laminated film having a two-layer structure produced therefrom.

In the method for surface modification of the polyimide film of the present invention, a silane-based coupler prepared by first performing a plasma treatment on a surface of a polyimide film, and adding 0.25 to 1 mole of the compound represented by Formula 2 to 1 mole of the compound represented by Formula 1 By immersing in the solution containing the ring agent and surface treatment, and performing the secondary plasma treatment sequentially, the surface of the conventional polyimide film is simplified than the modification method, and copper sputtering and electrolytic copper plating method on the surface of the modified polyimide film The manufactured two-layer flexible copper foil laminated film maintains excellent adhesion strength between polyimide film and copper foil and excellent adhesion strength even at high temperature for a long time, so it is for flexible printed circuit board, TCP (Tape Carrier Package), and COF (Chip On Film) It is advantageous for the substrate material use of electronic components such as these.

(Wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , m and n are as defined in the specification).

Copper Clad Laminated Film, Polyimide, Diamine, Sputtering, Electroplating

Description

METHOD OF SURFACE MODIFICATION OF POLYIMIDE FILM USING SILANES COUPLING AGENT, MANUFACTURING METHOD OF FLEXIBLE COPPER CLAD LAMINATE AND ITS PRODUCT THEREBY}             

1 is an FT-IR spectrum of a silane coupling agent used in Example 1 of the present invention,

2A is a SEM photograph of the polyimide film of Example 1 of the present invention,

2B is a SEM photograph of the polyimide film of Comparative Example 1 of the present invention,

2C is a SEM photograph of the polyimide film of Comparative Example 2 of the present invention,

2D is a SEM photograph of the polyimide film of Comparative Example 3 of the present invention,

3A is an AFM photograph of a polyimide film of Example 1 of the present invention,

3B is an AFM photograph of a polyimide film of Comparative Example 1 of the present invention,

3C is an AFM photograph of a polyimide film of Comparative Example 2 of the present invention,

3D is an AFM photograph of a polyimide film of Comparative Example 3 of the present invention,

4 is an ESCA analysis of the polyimide film of the present invention,

5 is a schematic diagram of the plasma apparatus used in the present invention,

6 is a schematic diagram of the pulse DC spatter equipment used in the present invention.

The present invention relates to a surface modification method of a polyimide film, a method for producing a flexible copper foil laminated film using the same, and a flexible copper foil laminated film having a two-layer structure manufactured therefrom, and more specifically, to a primary plasma treatment of a polyimide film, Surface modification method of the polyimide film surface-impregnated in a solution containing a silane coupling agent and subsequently secondary plasma treatment surface modification of the polyimide film, a method of manufacturing a polyimide copper clad laminated film having a two-layer structure using the same And it relates to a polyimide flexible copper foil laminated film excellent in the adhesive force produced therefrom.

Polyimide film has excellent heat resistance, electrical properties, chemical resistance and flex resistance compared to other polymer materials, and is used for electronic parts such as flexible printed circuit boards, auto bonding (TAB) tape, and chip on film (COF). It is variously used as an insulating substrate material. The copper foil laminated film used in the flexible printed circuit board is a three-layer copper foil laminated film using an epoxy adhesive, but the dimensional stability is poor due to the problem that the heat resistance of the adhesive is lowered, it is pointed out that it is not suitable for fine patterning applications have.

Therefore, the trend of changing from a three-layer (layer), which has been mainstream in recent years, to a two-layer structure product is accelerating. Such a two-layered structure directly die-casts a polyimide film onto a copper foil or adheres to a high temperature to remove the adhesive layer, thereby providing an advantage of easy formation of fine patterns and excellent flexibility. In addition, due to these advantages, the copper foil laminated film having a two-layer structure can broaden the marketability of display products such as cellular phone folders, LCDs, and PDP modules.

In particular, domestic substrate materials for electronic components depend mostly on imports, and there is an urgent need for research on flexible copper clad laminate (FCCL) applied a new method.

In the two-layer FCCL manufacturing method, a technique of laminating a polyimide film and a copper foil instead of an adhesive has been reported.

In addition, as a sputtering-electroplating method, a method of forming a thin seed metal layer (nickel, chromium, etc.) in advance by sputtering and then forming a copper layer having a desired thickness by electroplating has been proposed. The surface modification process must be preceded by the above, and in this process, a special seed layer is required, and in particular, when manufacturing a double-sided copper foil laminated film, a special manufacturing facility is required. In addition, in the high temperature and high humidity environment, the adhesive strength of the copper foil laminate is unstable, and thus the reliability is low, and there is a disadvantage of environmental pollution due to the drill work on the PCB (Printed Circuit Board) post-treatment process.

Accordingly, the present inventors have tried to solve the conventional problems and obtain a flexible copper foil laminated film having a two-layer structure, and as a result, the polyimide film is subjected to a first plasma treatment, and the solution containing the specific silane coupling agent according to the present invention is contained. By immersing the surface treatment and successive secondary plasma treatment, the polyimide film was surface-modified, and carried out under optimization conditions for copper sputtering and electrolytic copper plating, thereby providing a method for producing a flexible copper foil laminated film having a two-layer structure. The present invention was completed by confirming that the flexible copper foil laminated film thus prepared was excellent in adhesion between the film and the copper foil and maintained at high temperature for a long time.

It is an object of the present invention to provide a method of surface modification of a polyimide film.

Another object of the present invention is to provide a method for producing a flexible copper foil laminated film having a two-layer structure using the surface modification method of the polyimide film.

Still another object of the present invention is to provide a flexible copper foil laminated film having a two-layer structure formed on one side or both sides of a polyimide film produced by the manufacturing method.

In order to achieve the above object, the present invention is directed to a polyimide film surface

1) a first plasma treatment, and 2) a surface treatment by immersing in a solution containing a silane coupling agent prepared by adding 0.25-1 mol of the compound represented by the formula (2) to 1 mol of the compound represented by the following formula (1), 3) Provided is a method for surface modification of a polyimide film that is sequentially subjected to secondary plasma treatment.

Formula 1

Formula 2

(Wherein R ₁ , R ₂ , and R ₃ are hydrogen or a C _{1 to} C ₁₀ alkyl group or vinyl group, R ₄ and R ₅ are C ₁ to C ₄ alkyl groups, and R ₆ is C ₁ to C ₅ is an alkyl group, an aryl group or a cyano group, m is 1 to 5, and n is 1 to 3.)

In the above, the solution containing the silane coupling agent is a solution containing 0.01 to 10% by weight of the silane coupling agent, and the polyimide film is immersed in the solution for 1 to 60 minutes. In addition, the solution containing the silane coupling agent is prepared by dissolving the silane coupling agent in one or more mixed solvents selected from the group consisting of water, acetone, methanol, ethanol and isopropanol.

Plasma treatment is performed using a direct current or 60 Hz high frequency power supply, the output is 20 to 100 W, the pressure in the vacuum chamber is maintained at 1 × 10 ^{−3 to} 1 × 10 ⁻⁵ torr, and is performed for 10 to 1,000 seconds.

In another aspect, the present invention provides a method for producing a flexible copper foil laminated film using a method of modifying the surface of the polyimide film. More specifically, the surface-modified polyimide film is sputtered for 1 to 10 hours at 0.5 to 30 mA and 50 to 500 W on one or both sides of the film to form a copper sputtering layer, and the copper sputtering layer is electroplated. It consists of forming an electrocopper plating layer.

The thickness of the said copper sputtering layer is 500-5,000 kPa, and the thickness of the said electroplated copper layer is 1-50 micrometers.

In another aspect, the present invention is a copper sputtering layer having a thickness of 500 ~ 5,000Å in the cross section of the polyimide film produced by the surface modification method; And an electrocopper plating layer having a thickness of 1 to 50 µm on the copper sputtering layer. Provided in this section is a polyimide flexible copper foil laminated film having a two-layer structure.

In addition, the present invention is a copper sputtering layer having a thickness of 500 ~ 5,000Å on both sides of the polyimide film produced by the surface modification method; And a copper electroplating layer having a thickness of 1 to 50 μm on the copper sputtering layer. The polyimide flexible copper foil laminated film having a two-layer structure formed on both surfaces thereof is provided.

Hereinafter, the present invention will be described in detail.

The present invention is to provide a polyimide flexible copper foil laminated film with improved adhesion, 1) the first plasma treatment on the surface of the polyimide film, 2) compound represented by formula 2 to 1 mole of the compound represented by the formula (1) 0.25 Provided is a method for surface modification of a polyimide film in which a surface treatment is performed by immersion in a solution containing a silane coupling agent prepared by adding 1 mol.

Formula 1

Formula 2

(Wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , m and n are as defined above.)

The polyimide film that can be used in the present invention is not particularly limited as long as it has a thickness of 10 to 100 μm, even if it is synthesized or commercially available. Examples thereof include Dupont's Kapton H, Kapton E, Japan Upbex-S from Ube, or Apical from Kaneka, Japan Use film.

In the surface modification method of the polyimide film of the present invention, the first plasma treatment is a step of introducing a hydrophilic group to the surface of the polyimide film, and the plasma treatment is performed by argon, oxygen, nitrogen alone, or argon and oxygen, argon, nitrogen, and nitrogen. It is preferable to introduce a mixed gas of an appropriate ratio of and oxygen and to treat the plasma. The proper ratio of these mixed gases is 0.5 to 5 cc / min.

Plasma treatment is performed using a direct current or 60 Hz high frequency power supply, the output is 20 to 100 W, the pressure in the vacuum chamber is maintained at 1 × 10 ^{−3 to} 1 × 10 ⁻⁵ torr, and is performed for 10 to 1,000 seconds. At this time, if the polyimide film is subjected to plasma treatment for a long time at a high output in a gas atmosphere containing excessively excessive oxygen, nitrogen, and argon, the polyimide film surface may be subjected to enormous damage such as carbonization. The inherent characteristics are deteriorated and it cannot serve as an insulator of a substrate.

In the surface modification method of the polyimide film of the present invention, the step of surface treatment by immersion in the solution containing the silane coupling agent is a solution containing a hydrophilic group and a silane coupling agent formed on the surface of the polyimide film due to the first plasma treatment By graft-reaction with, high adhesive force between a polyimide film and copper foil can be provided.

The silane coupling agent of the present invention is mixed with an equal amount of an organosilane epoxy to an imidazole derivative and reacted at 50 to 150 ° C. for 60 minutes in a nitrogen atmosphere to prepare a compound of Formula 1, and a compound of Formula 1 To the compound of formula (2), 0.25 to 1 mole was added, the mixture was reacted at 150 to 200 ° C for 1 to 5 hours, and the resulting methanol was removed under reduced pressure to prepare a silane coupling agent.

1 is an FT-IR spectrum result of the silane coupling agent used in Example 1 as an embodiment of the present invention. From the above results, functional groups of imidazole and silane were identified.

The solution containing the silane coupling agent of the present invention is a solution containing 0.01 to 10% by weight of the silane coupling agent, and the polyimide film is immersed for 1 to 60 minutes. At this time, the solvent that can be used in the preparation of the solution containing the silane coupling agent is not particularly limited, but preferably a single or a mixture of two or more selected from the group consisting of water, acetone, methanol, ethanol and isopropanol having a low boiling point Solvent is used.

The coupling agent composition is used alone or mixed with an organic solvent and water to prepare a solution at a concentration of 0.01 to 10% by weight, and then immersed the polyimide film. At this time, the immersion time is preferably carried out for 1 to 60 minutes, less than 1 minute is not preferable because the silane coupling agent is not sufficiently reacted, and if it exceeds 60 minutes, the difference in the reaction, adhesion and heat resistance of the reaction time It is not desirable because there is no.

2A to 2D are scanning electron microscope (SEM) photographs showing the surfaces of the polyimide film prepared in Example 1 of the present invention and the polyimide film prepared in Comparative Examples 1 to 3. FIG. Figure 2a is Example 1, Figure 2b is Comparative Example 1, Figure 2c is Comparative Example 2, and Figure 2d is Comparative Example 3, in the case of Example 1 surface-treated the polyimide film by the method of the present invention, Regular roughness was confirmed.

3A to 3D are AFM (Atomic Force Microscopy) photographs of the surface of the polyimide film prepared in Example 1 of the present invention and the polyimide film prepared in Comparative Examples 1 to 3, wherein FIG. 3A is performed. Example 1, FIG. 3B shows the comparative example 1, FIG. 3C shows the comparative example 2, and FIG. 3D shows the comparative example 3. FIG. From the above result, in the case of Example 1 of this invention which surface-treated the polyimide film, the result which the very small protrusion showed on the surface is shown.

Figure 4 is an ESCA analysis of the polyimide film of the present invention, in the case of Example 1 treated with the surface modification method of the present invention, the oxygen content is significantly increased, showing a high degree of hydrophilicity of the polyimide film It was confirmed.

After the immersion process, the reaction was carried out for 1 to 60 minutes at a temperature of 50 ~ 100 ℃, after the reaction the surface-modified polyimide film is washed with distilled water and alcohol solvent to remove the unreacted solution, the surface is 100 ℃ or less Dry sufficiently in an oven to prepare for the next step.

Subsequently, in the method for modifying the surface of the polyimide film of the present invention, the secondary plasma treatment introduces an oxygen functional group to the surface of the polyimide film, thereby providing a function of imparting a higher hydrophilic group to the lowered polyimide film surface.

At this time, the secondary plasma treatment is performed in the same manner as the primary plasma treatment.

As a schematic diagram of the plasma apparatus 10 of this invention of FIG. 5 , the vacuum chamber 2 wound the polyimide film 3 by the roller 4, and was maintained at 1 * 10 <^{-3> -1} * 10 <^-5> torr Plasma source (6) fixed in the upper and lower sides of the vacuum chamber (2) to form an atmosphere by introducing (1), (5) argon gas or oxygen gas or mixed gas of argon and oxygen in the range of about 5 to 30 sccm. Plasma treatment is performed by adjusting (8) to 1 to 100 mA current and 0.25 to 10 KV power.

The present invention provides a method for producing a flexible copper foil laminated film using the surface modification method of the polyimide film. More specifically, the manufacturing method of the present invention

1) surface modification method of the polyimide film of the present invention, the step of modifying the surface of the polyimide film;

2) copper sputtering at 0.5 to 30 mA and 50 to 500 W for 1 to 10 hours on one or both surfaces of the polyimide film dried in the step, thereby forming a copper sputtering layer; And

3) electroplating the copper sputtering layer to form an electrocopper plating layer.

The surface modification method of the polyimide film of step 1 is as described above, the surface modification process is the first plasma treatment to introduce a hydrophilic group on the surface, immersed in a solution containing a silane coupling agent surface treatment Through the graft reaction, high adhesion between the polyimide film and the copper foil is provided, and subsequently, secondary plasma treatment introduces an oxygen functional group onto the film to impart higher hydrophilic groups.

Step 2 is a sputtering step of forming a thin film of copper by impinging a copper atom on the surface-modified polyimide film.

A sputtering step of the present invention is performed by using the pulse (pulse) DC spa emitter device 20 is shown in Fig. The surface-modified polyimide film 13 is wound on the roller 14 in this step, and argon gas is about 5 to 30 sccm in the vacuum chamber 12 maintained at 1 × 10 ⁻³ to 1 × 10 ⁻⁵ torr. (11) is formed to form an atmosphere, and the sputtering process is performed for 1 to 10 hours while the 0.5 to 30 mA current is adjusted to 50 to 500 W of power to maintain the thickness of 500 to 5,000 mW. At this time, when the thickness of the copper sputtering layer due to spattering is less than 500 μs, pinholes may occur or electricity may not be applied during electroplating, or the adhesion of plating may be weak, and when the thickness exceeds 5,000 μs, energy loss may occur. Many and too thick are undesirable for use as substrate materials.

Subsequently, step 3 is a step in which a polyimide film having a copper sputtering layer is formed in an electroplating bath of copper sulfate and sulfuric acid aqueous solution, laminating a thin copper film of electroplating on the copper thin film, and manufacturing a copper foil laminated film. At this time, the thickness of the preferable copper foil is 1-50 micrometers, and when an electric copper plating layer, ie, the thickness of copper foil is less than 1 micrometer, a pinhole is observed and difficult to handle in a copper foil laminated film, and when it exceeds 50 micrometers, It is unpreferable in terms of reduced precision of line width or light weight and small size in component mounting.

The present invention provides a polyimide flexible copper foil laminated film having a two-layer structure, which is prepared by the above production method.

Polyimide flexible copper foil laminated film of the two-layer structure of the present invention comprises a copper sputtering layer having a thickness of 500 to 5,000 kPa on the cross-section of the polyimide film surface-modified by the method of the present invention; And a copper electroplating layer having a thickness of 1 to 50 μm on the copper sputtering layer. It is a polyimide flexible copper foil laminated film having a two-layer structure.

In addition, the present invention is provided on both sides of the polyimide film produced by the surface modification method, to provide a two-layer polyimide flexible copper foil laminated film formed on both sides.

In the polyimide flexible copper foil laminated film of the present invention, the adhesion strength between the polyimide film and the copper foil is 0.8 kg / cm or more, and in particular, the adhesive strength between the polyimide film and the copper foil is maintained at 0.7 kg / cm or more even at 150 ° C. for 1 week or more. It has sufficient adhesion even when exposed to high temperatures.

The copper foil laminated film of the two-layer structure of the present invention forms a mask having a pattern, selectively exposes and removes the exposed copper thin film portion with a copper etching solution, and applies it to a method of forming a copper circuit pattern, thereby providing a flexible printed circuit board. Or it is useful for substrate materials of electronic components such as Tape Carrier Package (TCP), Chip On Film (COF).

Hereinafter, the present invention will be described in detail by way of examples.

The following examples are merely illustrative of the present invention, but the scope of the present invention is not limited to the following examples.

<Example 1>

Step 1: Preparation of Silane-Based Coupling Agent Composition

To 1 mole of 1-imidazole, 1 mole of 3-glycidoxy propyltrimethoxysilane was reacted at 100 ° C. for 60 minutes in a nitrogen atmosphere to prepare a compound of Formula 1, and to the prepared compound of Formula 1, 1 mol of tetramethyl orthosilicate, which is a compound of Formula 2, was added and reacted at 120 ° C for 2 hours. At this time, the produced methanol was removed under reduced pressure to prepare a silane coupling agent.

Step 2: Preparation of Polyimide Copper Foil Laminated Film

The polyimide film (Kapton E from DuPont) was placed in a chamber of a plasma apparatus, and the pressure was maintained at 3 × 10 ⁻³ torr under an argon atmosphere, and plasma was generated at a voltage of 1 KV and a current of 6 mA, followed by surface treatment for 200 seconds.

Subsequently, the silane coupling agent prepared in Step 1 was dissolved in 1 wt% of a 1: 1 mixed solvent of water and methanol to prepare a solution, and the surface-treated polyimide film was immersed in the solution for 20 minutes, followed by 100 ° C. The reaction was carried out in an oven for 60 minutes, and the reaction was washed with methanol and dried in the oven.

Put it back into the plasma chamber and regulate 5 × 10 ^-3 torr under argon atmosphere. Secondary plasma treatment was performed for 700 seconds by generating a plasma with a voltage of 1 KV and a current of 6 mA. Then put into a sputtering device 4 × 10 ^-3 torr The pressure was adjusted using argon gas in vacuum, and the current used was performed for 1 hour by adjusting the output to 200W at 3.5mA. The thickness of the laminated copper foil was made constant at 2,500 kPa. Subsequently, electroplating was performed in an electrolytic plating bath, and copper plating having a thickness of 20 µm was performed to manufacture a polyimide copper foil laminated film.

<Example 2>

Except for using the silane coupling agent prepared using the compound represented by Formula 1 and 2 represented by Example 2 of Table 1 , instead of the silane coupling agent of step 1 of Example 1, It carried out similarly to Example 1, and manufactured the 20 micrometers polyimide copper foil laminated | multilayer film.

<Example 3>

Instead of the silane coupling agent of step 1 of Example 1, a silane coupling agent prepared using the compound represented by Formula 1 and 2 represented by Example 3 of Table 1 was used.

Subsequently, a 1: 1 mixed solvent was prepared in a mixed solvent of water and methanol to dissolve the silane coupling agent at 0.5% by weight to prepare an immersion solution, and the surface treatment was performed in the same manner as in Step 2 of Example 1 above. The polyimide film (Kapton E manufactured by DuPont) was immersed for 10 minutes, and then reacted in an oven at 100 ° C. for 1 hour, washed with distilled water, and dried. Thereafter, secondary plasma treatment was carried out under the same conditions as in Example 1, and copper was laminated on a modified polyimide film by sputtering, followed by electroplating, to prepare a 45 μm polyimide copper foil laminated film.

<Example 4>

Instead of the silane coupling agent of step 1 of Example 1, using a silane coupling agent prepared using the compounds of formulas (1) and (2) represented by Example 4 of Table 1 , the silane coupling agent A 20-micrometer polyimide copper-clad laminated film was prepared in the same manner as in Example 3, except that 0.1 wt% was dissolved in a 1: 1 mixed solvent of water and methanol to prepare an immersion solution.

Example 5

Instead of the silane coupling agent of Step 1 of Example 1, using a silane coupling agent prepared using the compound of Formula 1 and 2 represented by Example 5 of Table 1 , the silane coupling agent A 20-micrometer polyimide copper-clad laminated film was prepared in the same manner as in Example 3, except that 0.1 wt% was dissolved in a 1: 1 mixed solvent of water and methanol to prepare an immersion solution.

<Example 6>

Instead of the silane coupling agent of step 1 of Example 1, a silane coupling agent prepared using the compounds represented by the formulas (1) and (2) represented by Example 6 of Table 1 was used, and the silane coupling agent A 20-micrometer polyimide copper-clad laminated film was prepared in the same manner as in Example 3, except that 0.1 wt% was dissolved in a 1: 1 mixed solvent of water and methanol to prepare an immersion solution.

<Example 7>

Instead of the silane coupling agent of step 1 of Example 1, using a silane coupling agent prepared using the compounds of formulas (1) and (2) represented by Example 7 of Table 1 , the silane coupling agent A 20-micrometer polyimide copper foil laminated film was prepared in the same manner as in Example 3 except that the solution was dissolved in isopropanol at 0.5% by weight to prepare an immersion solution.

<Example 8>

Instead of the silane coupling agent of step 1 of Example 1, a silane coupling agent prepared using the compounds represented by Formulas 1 and 2 represented by Example 8 of Table 1 is used, and the silane coupling agent A 20-micrometer polyimide copper foil laminated film was prepared in the same manner as in Example 1 except that the solution was dissolved in ethanol at 0.1% by weight to prepare an immersion solution.

Example 9

The same procedure as in Example 1 was repeated except that a UFILEX-S (Upilex-S, Ube, Japan) film was used instead of the polyimide film used in Step 1 of Example 1, and the thickness of A polyimide copper foil laminated film was produced.

Comparative Example 1

Copper sputtering and electroplating were carried out in the same manner as in Example 1, except that the surface modification process using the primary plasma, the coupling agent and the secondary plasma was omitted for the polyimide film (Kapton E from DuPont). The 20 micrometers polyimide copper foil laminated | multilayer film was manufactured.

Comparative Example 2

The polyimide film (Kapton E of DuPont) was subjected to the first plasma treatment in the same manner as in Example 1, except that the surface modification process using the coupling agent and the subsequent secondary plasma treatment were omitted, and the same method as in Example 1 was performed. Spattering and electroplating were performed to prepare a 20 μm polyimide copper foil laminated film.

Comparative Example 3

The polyimide film (Kapton E of DuPont) was subjected to the first plasma treatment in the same manner as in Example 1, and the surface was modified using the silane coupling agent used in Example 1, after which the secondary plasma treatment was omitted. And copper sputtering and electroplating were performed by the same method as Example 1, and the polyimide copper foil laminated | multilayer film of 20 micrometers was manufactured.

<Comparative Example 4>

The polyimide film (Kapton E of DuPont) was subjected to the first plasma treatment in the same manner as in Example 1, and surface-modified using the silane coupling agent used in Example 3, after which the secondary plasma treatment was omitted. And copper sputtering and electroplating were performed by the same method as Example 1, and the polyimide copper foil laminated | multilayer film of 20 micrometers was manufactured.

Comparative Example 5

The polyimide film (Kapton E of DuPont) was subjected to the first plasma treatment in the same manner as in Example 1, and the surface was modified using the silane coupling agent used in Example 7, after which the secondary plasma treatment was omitted. And copper sputtering and electroplating were performed by the same method as Example 1, and the polyimide copper foil laminated | multilayer film of 20 micrometers was manufactured.

Experimental Example 1

The characteristic of the polyimide copper foil laminated | multilayer film manufactured by the said Example and the comparative example was measured as follows.

1. Measurement of adhesive strength

The copper foil film prepared after the electroplating process in Examples 1 to 9 and Comparative Examples 1 to 5 was patterned by using an acid paint or an acid resistant tape, and then etched using an etching solution made of sulfuric acid and copper sulfate solution. By evaluating the physical properties of the peel adhesive strength, the results of the contact angle and the adhesive strength are shown in Tables 2 and 3 .

From the results of Tables 2 and 3, in the case of the polyimide copper foil laminated film subjected to the surface modification process of the present invention, the adhesive strength between the polyimide film and copper showed an adhesive strength of 0.8 kg / cm or more. In addition, as a result of an aging test in which the polyimide flexible copper foil laminated film of the present invention was maintained at 150 ° C. under degradation conditions of one week or more, by maintaining the adhesive strength of 0.7 kg / cm or more, sufficient adhesive strength was maintained even when exposed to high temperature for a long time.

2. Measurement of Atomic Composition of Polyimide Surfaces

The surface of the polyimide copper-clad laminated film prepared in Examples and Comparative Examples was analyzed by surface analysis using ESCA (Electron Spectroscopy of Chemical Analysis) to analyze the atomic ratio.

Comparative Example 1 and the surface of the polyimide copper foil laminated film of Example 1 prepared by performing the first plasma treatment, coupling agent treatment and secondary plasma treatment of the present invention, or prepared by performing only the first plasma treatment The copper foil laminated film of 2 was compared and analyzed.

From the above results, in the case of Example 1 through the surface modification process of the present invention, the composition ratio of silicon atoms was found using a silane coupling agent, and the oxygen content was increased to obtain a polarized polyimide surface.

As described above, the present invention

First, the surface treatment process using a conventional ion beam by modifying the surface of the polyimide film surface by primary plasma treatment, surface treatment immersed in the solution containing the silane coupling agent of the present invention, and secondary plasma treatment Since it does not use a special seed layer, it is possible to reduce the environmental pollution caused by heavy metals while reducing costs.                     

Second, it is possible to provide a polyimide copper foil laminated film having a two-layer structure, and in particular, by performing surface modification on one or both surfaces of the polyimide film, it is possible to provide a double-sided polyimide copper foil laminated film as well as one side.

Although the present invention has been described in detail only with respect to the embodiments described, it will be apparent to those skilled in the art that various modifications and variations are possible within the technical spirit of the present invention, and such modifications and variations belong to the appended claims. .

Claims (10)

On the surface of polyimide film 1) primary plasma treatment, 2) surface treatment by immersing in a solution containing a silane coupling agent prepared by adding 0.25 to 1 mole of the compound represented by Formula 2 to 1 mole of the compound represented by Formula 1, 3) A method for surface modification of a polyimide film, characterized in that the secondary plasma treatment is performed sequentially. Formula 1

Formula 2

(Wherein R ₁ , R ₂ , and R ₃ are hydrogen or a C _{1 to} C ₁₀ alkyl group or vinyl group, R ₄ and R ₅ are C ₁ to C ₄ alkyl groups, and R ₆ is C ₁ to C ₅ is an alkyl group, an aryl group or a cyano group, m is 1 to 5, and n is 1 to 3.) The surface modification method of the polyimide film according to claim 1, wherein the solution containing the silane coupling agent contains 0.01 to 10% by weight of the silane coupling agent. The method of claim 1, wherein the immersion is carried out for 1 to 60 minutes. The method of claim 1, wherein the silane coupling agent is dissolved in a single or two or more mixed solvents selected from the group consisting of water, acetone, methanol, ethanol and isopropanol. Surface modification method of the polyimide film. 2. The plasma treatment according to claim 1, wherein the plasma treatment is performed using a direct current or a 60 Hz high-frequency power supply, the output is 20 to 100 W, and the pressure in the vacuum chamber is maintained at 1 × 10 ^{−3 to} 1 × 10 ⁻⁵ torr, for 10 to 1,000 seconds. Surface modification method of the polyimide film, characterized in that carried out. Modifying the surface of the polyimide film by the method of claim 1; Copper sputtering at 0.5 to 30 mA and 50 to 500 W on one or both surfaces of the polyimide film for 1 to 10 hours to form a copper sputtering layer; Electroplating the copper sputtering layer to form an electroplated copper layer; method for producing a flexible copper foil laminated film, characterized in that consisting of. The said copper sputtering layer is 500-5,000 mm thick, The manufacturing method of the said flexible copper foil laminated film of Claim 6 characterized by the above-mentioned. The method for producing the flexible copper foil laminated film according to claim 6, wherein the electroplated copper layer has a thickness of 1 to 50 µm. A copper sputtering layer having a thickness of 500 to 5,000 mm 3 on a cross section of the polyimide film surface-modified by the method of claim 1; And An electric copper plating layer having a thickness of 1 to 50 μm on the copper sputtering layer; Polyimide flexible copper foil laminated film having a two-layer structure, characterized in that formed on the cross section. A copper sputtering layer having a thickness of 500 to 5,000 kPa on both surfaces of the polyimide film surface-modified by the method of claim 1; And An electric copper plating layer having a thickness of 1 to 50 µm on the copper sputtering layer; Polyimide flexible copper foil laminated film having a two-layer structure, characterized in that formed on both sides.

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