KR20080046340A - Multi layer polyimide film and manufacturing method thereof - Google Patents

Abstract

A multi-layered polyimide film and a manufacturing method thereof are provided to increase the adhesive strength of thermoplastic and non-thermoplastic polyimide films and to produce the multi-layered polyimide film having both thermoplastic and non-thermoplastic properties during a polyimide film manufacturing process. A method for manufacturing a multi-layered polyimide film comprises the steps of: pouring at least two kinds of polyamic acid solutions(15,25) into plural dies(10,20) installed in parallel; discharging each polyamic acid solution from plural dies through eject ports(11,21) and stacking each discharged polyamic acid solution on a support body(30) progressing in one direction, in order; and drying and thermally treating the polyamic acid solution. The temperature of the dies is kept below the temperature not to cause dehydration in molecules of polyamic acid resin.

Description

Multi-layer polyimide film and manufacturing method

BRIEF DESCRIPTION OF THE DRAWINGS It is a perspective view which shows one form of the apparatus for manufacturing the multilayer polyimide film of this invention.

* Explanation of the main symbols in the drawings

10: 1st die 11: 1st discharge outlet

15 first polyamic acid solution 20 second die

21: second discharge port 25: the second polyamic acid solution

30: support

The present invention relates to a multilayer polyimide film and a method for producing the same.

Polyimide is excellent in thermal stability and has excellent mechanical and electrical properties, and is used as a heat-resistant film for electronics, a liquid crystal alignment film, a material for semiconductors, a material for molding parts, and an adhesive. In particular, in recent years, it has been spotlighted as a flexible printed circuit board (FPCB), tape automated bonding (TAB), and a heat-resistant heat coating material as a heat-resistant film for electric and electronics.

Among them, FPCB is widely used in computers and peripherals, communication equipment, and medical equipment because of its three-dimensional circuit configuration and high-density wiring. In this case, the core material of FPCB, FCCL (Flexible Copper Clad Laminate) is made of polyimide film as the main raw material, and when used as an insulating layer, the polyimide film and the conductor are bonded by using an adhesive such as epoxy. Has been.

However, the polyimide film has no polar group on the surface, and as time goes by, the adhesive strength of the adhesive decreases, and thus, the adhesive strength of the polyimide film is separated from the conductor, so that the polyimide film and the conductor are separated. Doing.

As the adhesive for forming the adhesive layer, a thermosetting adhesive such as epoxy or acrylic, which can be bonded at a relatively low temperature, is mainly used. However, since the thermosetting adhesive has low heat resistance and poor electrical properties, the adhesive does not sufficiently meet the characteristics required by FCCL. There is a point.

Therefore, the method of using the thermoplastic polyimide film which has adhesive force as an adhesive layer for bonding an insulating polyimide film and a conductor is proposed. That is, an adhesive layer may be formed by applying and drying a thermoplastic polyimide compound or a precursor thereof on one or both surfaces of an insulating non-thermoplastic polyimide film, or by heating and bonding a thermoplastic polyimide film.

In this case, however, a non-thermoplastic polyimide film is separately prepared, and thus, a separate thermoplastic film layer needs to be adhered thereto, thereby incurring inconvenience in process.

Thus, the present invention while seeking to eliminate the inconvenience of preparing each film separately while increasing the adhesion between the thermoplastic polyimide film and the non-thermoplastic polyimide film, the thermoplastic and non- thermoplastic in the manufacturing step of the polyimide film It was confirmed that the present invention can provide a method for producing a multilayer polyimide film having thermoplasticity at the same time.

Accordingly, it is an object of the present invention to provide a multi-layered polyimide film having different properties and a method of manufacturing the same.

The present invention for achieving the above object comprises the steps of respectively injecting at least two or more polyamic acid solution to a plurality of die installed in parallel; Simultaneously discharging each polyamic acid solution through each discharge port from the plurality of dies, and sequentially stacking the discharged respective polyamic acid solutions on a support traveling in one direction; And drying and heat treatment, wherein the die temperature is maintained below a temperature at which the polyamic acid resin does not cause intramolecular dehydration.

The die temperature is characterized in that -20 ~ 30 ℃.

The polyamic acid solution discharged from the plurality of discharge ports is characterized in that the viscosity is 500 ~ 20000 Poise.

The plurality of discharge ports are characterized in that the distance between the axis and the axis is 500 ~ 5000mm based on the central axis of the discharge port, the movement speed of the support is 1 ~ 30m / min.

In addition, the present invention is imidized together under the same conditions in a state in which the polyimide film obtained by the above production method, at least one or more thermoplastic polyimide precursor layers, and at least one or more non-thermoplastic polyimide precursor layers are laminated. Provided is a multilayer polyimide film comprising at least one or more thermoplastic polyimide layers and at least one or more non-thermoplastic polyimide layers formed by interlayer adhesion due to a polyimide layer.

The polyimide film is characterized in that the thickness is 10 ~ 100㎛.

Moreover, this invention provides the copper foil polyimide laminated body containing the polyimide film obtained by said manufacturing method on at least one surface of copper foil.

Referring to the present invention as described in more detail with reference to the accompanying drawings as follows.

BRIEF DESCRIPTION OF THE DRAWINGS It is a perspective view which shows one form of the apparatus for manufacturing the multilayer polyimide film of this invention.

In order to produce the multi-layered polyimide film of the present invention, as shown in FIG. 1, an apparatus including a plurality of dies 10 and 20 and a support 30 running in one direction is used.

The first die 10 and the second die 20 are provided in parallel, and polyamic acid solutions of different compositions are added thereto. The injected polyamic acid solution is discharged through the discharge ports 11 and 21 of the dies 10 and 20, and the first die 10 and the second die 20 are subjected to intramolecular dehydration of the polyamic acid resin. The viscosity of the discharged solution is lowered by keeping it below a temperature which does not occur. Polyamic acid solutions having different compositions have different characteristics such as degree of polymerization, viscosity, and the like, and therefore, it is necessary to control conditions such as temperatures of the dies 10 and 20 differently. Each of the dies 10 and 20 is provided with means (not shown) for controlling the temperature and the discharge rate separately, so that the conditions can be separately adjusted according to the characteristics of the solution introduced into each of the dies 10 and 20. have. Therefore, the temperature, thickness and discharge amount of each part can be adjusted according to the dies 10 and 20.

The temperature of the die 10, 20 is preferably maintained at -20 ~ 30 ℃, if the temperature is more than 30 ℃ intramolecular dehydration reaction of the polyamic acid resin may proceed to film or gelation, -20 If the temperature is less than 0 ° C., the viscosity may be so large that it may not be flattened or may be swollen or the discharge pressure may increase rapidly.

The method of maintaining the dies 10 and 20 below a temperature at which the intramolecular dehydration reaction of the polyamic acid resin does not occur is not particularly limited, but a device in which a refrigerant penetrates outside the dies 10 and 20 is used. A method of enclosing or cooling the dies 10 and 20 in advance and adding a polyamic acid solution may be used.

The first polyamic acid solution 15 and the second polyamic acid solution 25 are discharged onto the support 30 positioned below and spaced apart from the discharge ports 11 and 21 at regular intervals. The support 30 is traveling in one direction in which the first die 10 and the second die 20 are installed, and the first polyamic acid solution 15 discharged from the first discharge port 11 located rearward in the traveling direction. ) Is discharged to the support 30 and flows along the traveling direction, and the second polyamic acid solution 25 discharged from the second discharge port 21 is stacked thereon. Since the first polyamic acid solution 15 and the second polyamic acid solution 25 are in a gel state in which the viscosity is reduced, each of the solutions 15 and 25 is not mixed because the shape of the discharged state is maintained.

The support 30 serves as a support for transporting and stacking the discharged solutions 15 and 25, and is resistant to heat, does not react with the polyamic acid, and the dried polyamic acid solutions 15 and 25 can be easily detached. It can be used, for example, steel, stainless steel (SUS, steel use stainless) and the like can be used.

The thickness of the final polyimide film is preferably 10 ~ 100㎛ for FCCL application, in consideration of this to adjust the thickness of the polyamic acid solution (15, 25) laminated. The thickness of each of the polyamic acid solutions 15 and 25 may vary depending on the viscosity of the solutions 15 and 25 discharged from the respective discharge ports 11 and 21, the moving speed of the support 30, and the like. It is preferable that the moving speed of 1-30 m / min and the viscosity of the solution 15, 25 discharged are 500-20000Poise in order to obtain the film of the target thickness.

The distance between the first die 10 and the second die 20 is not particularly limited, but the distance between the axis and the axis of each of the discharge ports 11 and 21 based on the center axis of each of the discharge holes 11 and 21 ( It is preferable that a) is 50-5000 mm. The polyamic acid solution is simultaneously discharged from the first discharge port 11 and the second discharge port 21, but is not limited thereto. The first discharge port 11 and the second discharge port are considered in consideration of the relationship between the distance a and the discharge speed. At 21, the timing at which the polyamic acid solution is discharged may be adjusted differently. In this case, the discharge timings at the discharge ports 11 and 21 are sequentially discharged along the advancing direction of the support in consideration of the distance a.

 Polyamic acid solution (15, 25) laminated in two layers is dried and heat-treated and imidized to produce a polyimide film as in the conventional polyimide film production method. At this time, the solvent in the two-layer polyamic acid solution (15, 25) is dried and firmly adhered to each other while evaporating, it is completed as a single film through the imidization.

On the other hand, a polyamic acid solution is obtained by melt | dissolving and polymerizing an aromatic diamine component and an aromatic dianhydride component in a solvent, as is commonly known.

The aromatic diamine component and aromatic dianhydride component are not particularly limited, and commonly known components are used. For example, pyromellitic dianhydride (PMDA) or biphenyltetracarboxylic dianhydride (BPDA) can be used as the aromatic dianhydride component, and oxydianiline (ODA) or p-phenylenediamine is used as the aromatic diamine component. (p-PDA) and the like can be used.

At this time, the polyamic acid solution having different properties, that is, the polyamic acid solution that is a precursor of the non-thermoplastic polyimide compound and the polyamic acid solution that is the precursor of the thermoplastic polyimide compound are not particularly limited, and all known polyamic acid solutions Can be used, and well-known raw materials, reaction conditions, etc. can also be used also in a manufacturing method. Moreover, additives, such as an imidation catalyst and a hardening | curing agent, can be used as needed.

Here, the thermoplastic polyimide resin is -O-, -CO-, -NHCO-, -S-, -SO _2- , -CO-O-, -CH _2- , -C (CH ₃ ) ₂ between the aromatic rings. It can be obtained through the polymerization of diamines and acid dianhydrides, which are soft monomers containing a chain of-. For example, ODPA (4,4'- oxydi (phthalic anhydride)), BTDA (3,3 ', 4,4'- benzophenone tetracarboxylic dianhydride), BPADA (bisphenol A dianhydride), DPSDA as an acid dianhydride (3,3 ', 4,4'-diphenylsulfontetracarboxylic dianhydride), TMEG (ethylene glycol bis (anhydro trimellitate)), and the like, and as diamines, DDE, DABA (4,4'-diamino Benzanilide), APB (1,3-bis (3-aminophenoxy) benzene), PDPDA (4,4 '-(1,3-phenylenediisopropylidene) dianiline), BAPP (2,2-bis [-4- (4-aminophenoxy) phenyl] propane, BAPSM (bis [4- (3-aminophenoxy) phenyl] sulfone), DDS (3,3'-diaminodiphenyl sulfone), and the like.

In addition, the thermoplastic polyimide resin may include a hard monomer in molecular structure if it can achieve the technical purpose as a thermoplastic polyimide resin. The hard monomer is specifically -O-, -CO-, -NHCO-, -S-, -SO _2- , -CO-O-, -CH _2- , -C (CH ₃ ) between aromatic rings. _It can be defined as a _two -chain, ie a monomer in which no soft chain is present.

In the above described with reference to the drawings shown in Figure 1, it is not limited to this, it will be apparent to those skilled in the art that various changes can be made within the scope without departing from the spirit.

Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited by the Examples.

Synthesis Example 1 Synthesis of Non-thermoplastic Polyamic Acid Solution

580 g of N, N-dimethylformamide (DMF) was added to the reactor as a solvent, 55.8 g of 4,4-diaminodiphenyl ether (ODA) and 10.3 g of paraphenylenediamine (p-PDA) were added thereto. Diamine solution was prepared by stirring at ° C. 86.8 g of pyromellitic dianhydride (PMDA) was added thereto, followed by stirring for 4 hours until complete dissolution, thereby obtaining a non-thermoplastic polyamic acid solution (viscosity: 3120Poise, 30 ° C).

Synthesis Example 2 Synthesis of Thermoplastic Polyamic Acid Solution

300 g of N, N-dimethylformamide (DMF) and 28.5 g of 1,3 bis (4-phenoxy) benzenediamine were stirred in a nitrogen atmosphere in a reactor. 29.1 g of ', 4'-biphenyl tetracarboxylic dianhydride (BPDA) was added. The solution was added until completely dissolved and stirred for 4 hours to obtain a thermoplastic polyamic acid solution (viscosity: 7120Poise, 30 ° C).

<Example 1>

Using the apparatus of FIG. 1, 31.5 g of isoquinoline was added as a curing agent to 120 g of the non-thermoplastic polyamic acid solution prepared in Synthesis Example 1, and the stirred solution was added to the first die.

250 g of DMF was added to 100 g of the thermoplastic polyamic acid solution prepared in Synthesis Example 2, and the stirred solution was added to a second die.

The distance between the first die and the second die is such that the distance (a) based on the central axis of the first discharge port and the second discharge port is 1000 mm, so that the non-thermoplastic polyamic acid solution is discharged from the first discharge port and stabilization of the film forming curtain is achieved. After being made, the thermoplastic polyamic acid solution was discharged from the second discharge port.

The first die was maintained at 0 ° C. and the second die at 5 ° C.

The viscosity of the non-thermoplastic polyamic acid solution discharged from the first discharge port was 4500Poise, and the viscosity of the thermoplastic polyamic acid solution discharged from the second discharge port was 8100Poise.

A non-thermoplastic polyamic acid solution was discharged to a thickness of 150 μm on a SUS substrate running in one direction, and then flattened, and a thermoplastic polyamic acid solution was discharged to a thickness of 60 μm and stacked on top thereof.

After drying for 2 hours at 300 ℃, two layers of dried film is fixed on the support frame by desorption from the SUS substrate, and then dried and heat treated at 200 ℃ for 10 minutes, 20 minutes at 300 ℃, 1 minute at 400 ℃ 37 A polyimide film of μm was obtained.

<Example 2>

In Example 1, when the temperature of the first die was kept at −10 ° C. and the second die was kept at 20 ° C., the viscosity of the non-thermoplastic polyamic acid solution discharged was 5200 Poise, and the temperature of the thermoplastic polyamic acid solution discharged from the second discharge port was increased. A polyimide film was prepared in the same manner except that the viscosity was 6100 Poise.

<Example 3>

The polyimide film was prepared in the same manner as in Example 1 except that the thickness of the non-thermoplastic film in the gel state discharged by adjusting the discharge amounts at the first discharge port and the second discharge port was 50 μm and the thickness of the thermoplastic polyimide film was 20 μm. Prepared.

Comparative Example 1

The non-thermoplastic polyamic acid solution prepared in Synthesis Example 1 was applied on an SUS plate and dried at 100 ° C. for 5 minutes. After peeling the coating film of the gel film state from the SUS plate and fixed to the support frame, a non-thermoplastic polyimide film having a thickness of 25 μm was obtained by drying and heat treatment at 200 ° C. for 10 minutes, at 300 ° C. for 20 minutes, and at 400 ° C. for 1 minute.

The thermoplastic polyamic acid solution prepared in Synthesis Example 2 was applied on an SUS plate and dried at 100 ° C. for 5 minutes. The coating film of the gel film state was peeled off from the SUS plate and fixed to the support frame, followed by drying and heat treatment at 200 ° C. for 10 minutes, 300 ° C. for 20 minutes, and 400 ° C. for 1 minute to obtain a thermoplastic polyimide film having a thickness of 12 μm.

The two films were bonded by thermocompression bonding at a pressure of 30 kg / cm 2 at 200 ° C. for 30 minutes.

Experimental Example

In the polyimide film obtained according to the above Examples and Comparative Examples, the thermoplastic polyimide side was bonded to copper foil (Mitsui Co., Sec-III, 1/2 Oz) and laminated at 300 kg for 30 minutes at 30 kg _f / cm 2 for copper foil laminate. Was prepared, and the peel adhesion strength was measured according to ASTM 1876-72 using a universal testing machine (Instrone). The results are shown in Table 1 below.

Peel Strength (kgf / cm) Example 1 2.0 Example 2 1.8 Example 3 1.9 Comparative Example 1 1.6

From the above results, it can be seen that the adhesive force with the copper foil is equal to or greater than that of the comparative example, but the manufacturing process is much shorter and more efficient, and the manufacturing cost can be reduced.

As described in detail above, the present invention can provide a multi-layered polyimide film having different properties at the same time through a single process without separately preparing and bonding a polyimide film having different properties and a method of manufacturing the same.

Moreover, this invention can provide the polyimide film excellent in the adhesive force with copper foil, and its manufacturing method.

Claims (10)

Injecting at least two or more polyamic acid solutions into a plurality of dies installed in parallel; Simultaneously discharging each of the polyamic acid solutions from the plurality of dies through respective discharge ports, and sequentially stacking the discharged polyamic acid solutions on a support running in one direction; And A method for producing a multi-layer polyimide film, comprising the steps of drying and heat treatment, wherein the temperature of the die is kept below a temperature at which no intramolecular dehydration reaction of the polyamic acid resin occurs. The method of claim 1, The temperature of die | dye is -20-30 degreeC, The manufacturing method of the multilayer polyimide film characterized by the above-mentioned. The method of claim 1, Polyamic acid solution discharged from a plurality of discharge port is a manufacturing method of a multi-layer polyimide film, characterized in that the viscosity is 500 ~ 20000 Poise. The method of claim 1, A plurality of discharge port is a method of producing a multi-layer polyimide film, characterized in that the distance between the axis and the axis 50 to 5000mm based on the central axis of the discharge port. The method of claim 1, Method of producing a multi-layer polyimide film, characterized in that the movement speed of the support is 1 ~ 30m / min. The polyimide film obtained by the manufacturing method of Claim 1. At least one or more thermoplastic polyimide precursor layers and at least one or more non-thermoplastic polyimide precursor layers are imidized together under the same conditions in a laminated state, and at least one or more thermoplastic polyimide formed by interlayer adhesion due to the thermoplastic polyimide layer A multilayer polyimide film comprising a mid layer and at least one non-thermoplastic polyimide layer. The method according to claim 6 or 7, Polyimide film, characterized in that the thickness is 10 ~ 100㎛. The copper foil polyimide laminated body containing the polyimide film obtained by the manufacturing method of Claim 1 on at least one surface of copper foil. The copper foil polyimide laminated body containing the polyimide film of Claim 7 on at least one surface of copper foil.

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