KR102122938B1 - Bond ply layer for flexible copper clad laminated film and method for manufacturing the same - Google Patents

Abstract

The present invention discloses a bond ply layer for a flexible copper clad laminated film, and a method for manufacturing the same, in which a thermoplastic polyimide resin having low dielectric properties is coated on both sides of a fluorine-based resin layer to reinforce a low mechanical strength of a fluorine-based resin so that the utilization as a function of a bond ply for FCCL is improved. The method for manufacturing the bond ply layer for the flexible copper clad laminated film according to the present invention includes the steps of: (a) preparing a fluorine-based resin layer; (b) surface-treating both surfaces of the fluorine-based resin layer to have interfacial adhesion; and (c) coating a polyimide resin on the both surfaces of the surface-treated fluorine-based resin layer.

Description

BOND PLY LAYER FOR FLEXIBLE COPPER CLAD LAMINATED FILM AND METHOD FOR MANUFACTURING THE SAME}

The present invention relates to a bond ply layer applicable to a flexible copper foil laminated film (FCCL) for high-frequency wireless communication and a method of manufacturing the same.

Flexible copper foil laminated film (FCCL) is a laminate of conductive copper foil and polyimide resin, and is a material that is increasing in usage along with the trend of miniaturization and weight reduction of electronic devices.

Recently, the signal transmission rate in the GHz band has been generalized due to the development of a 4th generation wireless communication device represented by LTE. The circuit board material also requires corresponding technological development according to the tendency of the signal to be high-frequency, and for the impedance control in the high-frequency band, the low dielectric constant of the insulating resin constituting the circuit is required.

Antennas for receiving radio signals are typically manufactured by attaching a metal layer on which the electrical flow is caused by radio signals on the base film.

The loss generated in connection with the signal reception of the antenna includes loss due to the dielectric constant of the base film forming the base layer of the antenna, and signal loss generated physically by electrical resistance when a radio signal, that is, an electrical signal flows through the metal layer.

In this regard, a physical phenomenon in which the electrical flow by the wireless signal is more concentrated to the surface layer of the metal layer occurs in comparison with the wireless signal having a relatively low frequency frequency.

On the other hand, when manufacturing an antenna for wireless communication of 10 GHz or more, the dielectric constant and dielectric loss of the bond ply layer for FCCL should be low, and among them, a value that greatly affects results such as transmission loss is dielectric loss.

Accordingly, various configurations of a bond ply layer for FCCL using a polymer material having low dielectric loss have been attempted.

Polymer materials with low dielectric loss that can be used at frequencies above 10 GHz include liquid crystal polymer (LCP), modified PI (mPI), poly phenylene sulfide (PSP), and Teflon resin. However, LCP has difficulty in processing, mPI has a high dielectric loss value in the frequency band of 28 GHz or higher, and PPS and Teflon resins have problems of heat resistance and low mechanical strength.

Therefore, it is necessary to study the bond ply layer for FCCL that exhibits low dielectric constant and dielectric loss at high frequencies and has excellent mechanical properties.

An object of the present invention is to provide a method of manufacturing a bond ply layer for a flexible copper foil laminated film by improving the low mechanical strength of a fluorine-based resin layer by coating a thermoplastic polyimide resin having low dielectric properties on both sides of the fluorine-based resin layer.

It is also an object of the present invention to provide a bond ply layer for a flexible copper foil laminated film having excellent mechanical properties and low dielectric properties.

The objects of the present invention are not limited to the above-mentioned objects, and other objects and advantages of the present invention not mentioned can be understood by the following description, and will be more clearly understood by embodiments of the present invention. In addition, it will be readily appreciated that the objects and advantages of the present invention can be realized by means of the appended claims and combinations thereof.

A method of manufacturing a bond ply layer for a flexible copper foil laminated film according to the present invention comprises the steps of: (a) providing a fluorine-based resin layer; (b) surface-treating to have interfacial adhesion to both surfaces of the fluorine-based resin layer; And (c) coating polyimide resin on both surfaces of the surface-treated fluorine-based resin layer.

The bonding ply layer for the flexible copper-clad laminate film according to the present invention includes a fluorine-based resin layer surface-treated to have interfacial adhesion on both sides; And a polyimide resin layer coated on both surfaces of the surface-treated fluorine-based resin layer.

Bond ply layer for flexible copper foil laminated film according to the present invention and its manufacturing method are coated with thermoplastic polyimide resin having low dielectric properties on both sides of the fluorine-based resin layer, thereby reinforcing the low mechanical strength of the fluorine-based resin to improve the FCCL bond ply. The utilization as a function can be improved.

In addition, the bond ply layer of the present invention has an effect of improving mechanical properties such as tensile strength, elongation, and elasticity while securing excellent low dielectric properties equal to or higher than that of the fluorine-based resin.

In addition to the above-described effects, the concrete effects of the present invention will be described together while describing the specific matters for carrying out the invention.

1 is a flow chart of a bond ply layer for a flexible copper foil laminated film according to the present invention and a method of manufacturing the same.
Figure 2 is a cross-sectional view of the bond ply layer for a flexible copper foil laminated film according to the present invention.

The above-described objects, features, and advantages will be described in detail below with reference to the accompanying drawings, and accordingly, a person skilled in the art to which the present invention pertains can easily implement the technical spirit of the present invention. In the description of the present invention, when it is determined that detailed descriptions of known technologies related to the present invention may unnecessarily obscure the subject matter of the present invention, detailed descriptions are omitted. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The same reference numerals in the drawings are used to indicate the same or similar components.

In the following, the arrangement of any component in the "upper (or lower)" or "upper (or lower)" of the component means that any component is disposed in contact with the upper surface (or lower surface) of the component. In addition, it may mean that other components may be interposed between the component and any component disposed on (or under) the component.

Hereinafter, a bond ply layer for a flexible copper foil laminated film according to some embodiments of the present invention and a method of manufacturing the same will be described.

The present invention is an invention in which a thermoplastic polyimide having low dielectric properties is coated on both surfaces of a fluorine-based resin layer in order to reinforce low mechanical strength in order to improve the utilization of the fluorine-based resin as a bond ply layer for FCCL.

1 is a flow chart of a bond ply layer for a flexible copper-clad laminate film according to the present invention and a method of manufacturing the same. Referring to Figure 1, the method of manufacturing a bond ply layer for a flexible copper-clad laminate film according to the present invention comprises the steps of providing a fluorine-based resin layer (S110), surface-treating both surfaces of the fluorine-based resin layer (S120) and surface-treated And coating the polyimide resin on both sides of the fluorine-based resin layer (S130).

First, the fluorine-based resin layer 10 is prepared.

The fluorine-based resin layer 10 may be formed by applying a fluorine-based resin on a substrate.

The substrate may be a rigid glass substrate, but is not limited thereto. After forming the fluorine-based resin layer on the substrate and manufacturing the bond ply layer for the flexible copper-clad laminate film through a number of subsequent processes, the bond ply layer for the flexible copper-clad laminate film is separated from the substrate.

The fluorine-based resin is a polymer having low dielectric loss, and is suitable for use in a high frequency band because it exhibits a dielectric constant (D _k ) of 2 or less at 10 GHz or more and a dielectric loss (D _f ) of 0.001 or less at 10 GHz or more.

Examples of the fluorine-based resin include polytetrafluoroethylene (PTFE), ethylene-tetrafluoroethylene copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, and tetrafluoro Roethylene-hexafluoropropylene-vinylidene fluoride copolymer.

As a method of applying the fluorine-based resin, it may be performed by spin coating, bar coating, or the like. The formed fluorine-based resin layer may have a thickness of approximately 5 to 300 μm. When the thickness of the fluorine-based resin layer is outside this range, it may be difficult to exhibit excellent physical properties when applied to FCCL.

Subsequently, surface treatment is performed to have interfacial adhesion on both surfaces of the fluorine-based resin layer.

In the present invention, in order to improve the interface adhesion between the fluorine-based resin and the polyimide resin to be described later, both surfaces of the fluorine-based resin layer can be surface-treated.

The surface treatment aims to enhance the adhesion between the fluorine-based resin layer and the polyimide resin layer, and the surface treatment may be performed by performing plasma treatment or corona discharge, or etching the surface using a sodium ammonia etching method. .

In the plasma treatment, when particles having high energy raised in the plasma state collide with the surface of the fluorine-based resin layer, the energy is transferred to the surface of the collided fluorine-based resin layer. Accordingly, the surface of the fluorine-based resin layer may be chemically or physically activated to improve adhesion between the layers. For example, oxygen plasma may be treated at 200 to 1000 W.

Corona discharge may be performed by variously controlling the surface treatment source, and the source may include one or more of air, oxygen, and nitrogen. Corona discharge exhibits a synergistic effect of physical surface modification of the discharge itself and chemical surface modification due to functional group formation. In chemical surface modification, high-energy electrons or ions collide and radicals or ions are generated in the fluorine-based resin layer, and air, oxygen, nitrogen, ozone, and moisture around them react, such as carbonyl, carboxyl, hydroxy, and cyano groups. A polar functional group such as is introduced to cause chemical surface modification.

In the sodium ammonia etching method, when precipitating PTFE in a solution formed by dissolving sodium metal in an ammonia liquid, sodium fluoride (NaF) is generated, and the surface of PTFE is etched, and the PTFE surface is chemically modified.

As described above, when the adhesive strength of the surface-treated fluorine-based resin layer to the polyimide resin layer is confirmed by the ASTM D3359 method at 25° C., it exhibits properties of up to 5B at approximately 700 g adhesive strength. As the adhesive strength of the fluorine-based resin layer satisfies this range, it is possible to prevent the floating phenomenon between the layers and to improve the durability of the product.

On the other hand, with respect to the polyimide resin layer, the adhesive strength at 25°C of the surface-treated fluorine-based resin layer shows a property of about 0B at 400 g adhesion when confirmed by the ASTM D3359 method.

Subsequently, in order to reinforce the mechanical strength of the fluorine-based resin layer, a thermoplastic polyimide resin having low dielectric properties is coated on both surfaces of the surface-treated fluorine-based resin layer.

Polyimide resin has the most excellent heat resistance, flexibility and strength among plastic materials. The polyimide resin can withstand characteristics from 273°C down to 400°C without changing its characteristics, and the amount of gas generated in a vacuum environment is small, and there are few deformations and residues due to strong acidic chemicals.

The monomer used for synthesizing the thermoplastic polyimide resin having the low dielectric properties of the present invention may be a monomer containing at least one of methyl group, ether group, ketone group and carboxy group.

Specifically, the monomer may include at least one of a diamine monomer, a dianhydride monomer and a dielectric constant reducing monomer. Preferably, a diamine monomer and a dianhydride monomer may be included to synthesize the polyimide resin.

For example, diamine monomers include 2,2-bis(4-(4-aminophenoxy)phenyl)propane (BAPP), 1,3-bis(4-aminophenoxy)benzene (TPE-R), 4 ,4-oxydianiline (ODA), m-bis(4-(4-aminophenoxy)phenyl)sulfone (m-BAPS).

Dianhydride monomers include 4,4'-oxydiphthalic anhydride (ODPA), biphenyl-tetracarboxylic acid (BPDA), 4,4'-(4,4'-isopropylidene-diphenoxy) Bis (phthalic anhydride) (BPADA).

The dielectric constant reducing monomer may include at least one of poly-diaminosiloxane (PSX) and dimer diamine.

The pre-polymerized polyamic acid (PAA) precursor may be synthesized by dissolving the diamine monomer and the dianhydride monomer presented above in an organic solvent.

The organic solvent is DMF (dimethylformamide), NMP (N-methyl-2-pyrrolidone), DMSO (Dimethyl Sulfoxide), DMAc (Dimethylacetamide), methyl lactate, methyl lactate, ethyl lactate, n-propyl It may include one or more of n-propyl Lactate, n-butyl Lactate, acetone, and diethyl acetate.

With respect to 100 parts by weight of the organic solvent, it may include 1 to 25 parts by weight of the proposed monomer. When the added amount of the monomer is outside the range of 1 to 25 parts by weight, the solubility of the monomer is poor and synthesis of the PAA precursor may not be smoothly performed.

The thermoplastic polyimide resin having low dielectric properties may be synthesized by including the synthesized PAA precursor.

The thermoplastic polyimide resin having low dielectric properties to be synthesized may have a viscosity of 50 cP to 20,000 cP at 25°C, and a weight average molecular weight of 1×10 ³ to 1×10 ⁶ . And the thermoplastic polyimide resin may have a glass transition temperature of about 100 ~ 350 ℃.

At this time, in the process of synthesizing the thermoplastic polyimide resin, a fluorine-based resin powder coated with the above-described monomer may be further added in a core-shell form. A spherical fluorine-based resin powder is present in the core, and the suggested monomer is coated on the shell, and the core-shell structured powder may be nano powder having a particle diameter of approximately 1 to 30 nm. The fluorine-based resin powder coated with the proposed monomer may exhibit excellent dispersibility in a solvent, and the polyimide resin layer containing the same may exhibit better low-k dielectric properties.

In the present invention, by coating the synthesized PAA precursor on the surface-treated fluorine-based resin layer and heating it, a thermoplastic polyimide resin layer having low dielectric properties can be formed on both surfaces of the fluorine-based resin layer.

Heating may be performed in a stepwise heat treatment in a region of approximately 100 to 300° C. Specifically, first heat treatment, second heat treatment performed at a temperature higher than the first heat treatment, and third heat treatment performed at a temperature higher than the second heat treatment. Can be performed with.

For example, it may be performed through conditions of a first heat treatment at about 100°C, a second heat treatment at 200°C or less, and a third heat treatment at 300°C or less.

With regard to the heating process, it may be difficult to secure a stable polyimide resin layer when heat treatment is performed in a region lower than 100°C. Conversely, when heat treatment is performed in a region higher than 300°C, a poor appearance of the fluorine-based resin layer may occur due to low heat resistance of the fluorine-based resin layer.

In the process of coating the polyimide resin on the surface-treated fluorine-based resin layer, the polyimide resin may be coated to have a thickness smaller than the thickness of the fluorine-based resin layer.

For example, the polyimide resin layer may be formed to have a thickness of 1 to 300 μm. If it is outside this range, it is insufficient to exhibit the effect of low dielectric properties of the polyimide resin layer.

2 is a cross-sectional view of the bond ply layer for a flexible copper-clad laminate film according to the present invention.

As shown in FIG. 2, the bond fly layer 100 for the flexible copper-clad laminate film according to the present invention has a surface-treated fluorine-based resin layer 10 and surface-treated fluorine-based resin layer 10 to have interfacial adhesion on both sides. ) Includes a polyimide resin layer 20 coated on both sides.

The description of the fluorine-based resin layer 10 is as described above.

The thermoplastic polyimide resin layer 20 has 2,2-bis(4-(4-amino phenoxy)phenyl)propane (BAPP), 1,3-bis(4-aminophenoxy)benzene ( TPE-R), 4,4-oxydianiline (ODA), m-bis(4-(4-aminophenoxy)phenyl)sulfone (m-BAPS), 4,4'-oxydiphthalic anhydride ( ODPA), biphenyl-tetracarboxylic acid (BPDA), 4,4'-(4,4'-isopropylidene-diphenoxy)bis(phthalic anhydride) (BPADA), poly-diaminosiloxane ( PSX) and dimer diamines.

As described above, the bond ply layer 100 for the flexible copper-clad laminate film of the present invention includes a fluorine-based resin layer and a thermoplastic polyimide resin layer having low dielectric properties, thereby improving low mechanical strength of the fluorine-based resin, thereby providing excellent mechanical strength and low dielectric constant. Characteristics can be secured simultaneously.

The bond ply layer 100 for the flexible copper-clad laminate film may exhibit a tensile strength of 30 MPa or more, an elongation of 90% or more, and an elasticity of 600 MPa or more.

In addition, the bond fly layer 100 for a flexible copper-clad laminate film may exhibit a dielectric loss (D _f ) of less than 0.003 at 10 GHz or higher and a dielectric constant (D _k ) of 3 or lower at 10 GHz or higher.

As described above, a specific embodiment of the bonding ply layer for a flexible copper-clad laminate film and its manufacturing method is as follows.

1. Manufacture of a bond ply layer for flexible copper foil laminated films

Example

Polytetrafluoroethylene (PTFE) was spin coated on a glass substrate to form a 50 µm thick PTFE resin layer.

Subsequently, surface treatment was performed by plasma treatment at 500 W on both surfaces of the PTFE resin layer.

Subsequently, in order to synthesize the polyimide resin, 0.11 mol of 3-bis(4-aminophenoxy)benzene was dissolved in 410 g of DMAc solvent, and then 0.136 mol of biphenyl-tetracarboxylic acid was added to react, followed by dimer diamine 0.027. After adding mol to complete the reaction, a polyamic acid (PAA) precursor was synthesized. After coating the synthesized PAA precursor on both surfaces of the PTFE resin layer, a thermoplastic polyimide resin layer having a thickness of 5 μm was formed through imidization through heat treatment conditions of 100° C. 5 minutes, 200° C. 5 minutes, and 300° C. 5 minutes.

A bond ply layer was prepared by removing the glass substrate.

Comparative example

After spin coating polytetrafluoroethylene (PTFE) on a glass substrate to form a 50 µm thick PTFE resin layer, the glass substrate was removed.

2. Method for evaluating physical properties and results

1) Tensile strength (Mpa)

After each specimen is prepared according to ASTM D-638, the tensile strength of the specimen is broken until the specimen breaks at a rate of 50.8 mm/min using a universal testing machine (UTM, Universal Testing Machine, model name WITHLAB WL2100). Calculated and shown in Table 1

2) Elongation at break (%)

After each specimen is prepared according to ASTM D-638, it is stretched at a rate of 50.8 mm/min using a universal testing machine (UTM, Universal Testing Machine, model name WITHLAB WL2100) until the specimen breaks. Table 1 shows the elongation at break by measuring.

3) Tensile modulus (Mpa)

After each specimen is prepared according to ASTM D-638, it is stretched until the specimen breaks at a rate of 5.08 mm/min using a universal testing machine (UTM, Universal Testing Machine, WITHLAB WL2100). The tensile modulus was calculated by calculating the slope and is shown in Table 1.

4) Dielectric constant (D _k ), dielectric loss (D _f )

Dielectric constant and dielectric loss are different depending on the measurement frequency band. In the 1 GHz and 10 GHz regions, D _k and D _f were measured by a AET, Inc. measuring instrument according to JIS C2565 using the cavity resonator method. As for the measurement method in the 28 GHz region, D _k and D _f were measured by a KEYCOM Corp measuring instrument according to JIS R 1660-2 using an open resonator method.

[Table 1]

[Table 2]

Referring to the results of Table 1 and Table 2, the bond ply layer of the present invention has a structure in which a thermoplastic polyimide is coated on both sides of the fluorine-based resin layer, thereby improving the low mechanical properties of the existing fluorine-based resin layer and also showing low dielectric properties. It shows the result of maintaining without significant change.

This is expected to improve the utilization of the fluorine-based resin as a bond ply layer for FCCL according to the manufacturing method of the present invention.

As described above, the present invention has been described with reference to the exemplified drawings, but the present invention is not limited by the examples and drawings disclosed in the present specification, and can be varied by a person skilled in the art within the scope of the technical idea of the present invention. It is obvious that modifications can be made. In addition, although the operation effect according to the configuration of the present invention is not explicitly described while explaining the embodiment of the present invention, it is natural that the effect predictable by the configuration should also be recognized.

10: fluorine-based resin layer
20: polyimide resin layer
100: Bond fly layer for flexible copper-clad films

Claims (10)

(a) preparing a fluorine-based resin layer;
(b) surface-treating to have interfacial adhesion to both surfaces of the fluorine-based resin layer; And
(c) coating a thermoplastic polyimide resin on both surfaces of the surface-treated fluorine-based resin layer; including,
The thermoplastic polyimide resin has a viscosity of 50 to 20,000 cP at 25°C, and a weight average molecular weight of 1 x 10 ³ to 1 x 10 ⁶ ,
The thermoplastic polyimide resin includes a diamine monomer, a dianhydride monomer, and a monomer for reducing dielectric constant,
The dielectric constant reduction monomer is poly-diaminosiloxane (PSX), a method of manufacturing a bond ply layer for a flexible copper foil laminated film comprising at least one of dimer diamine.
According to claim 1,
In the step (b), a method of manufacturing a bond fly ply layer for a flexible copper-clad laminate film by performing a plasma treatment, corona discharge, or surface etching process.
According to claim 1,
The diamine monomer is 2,2-bis(4-(4-amino phenoxy)phenyl)propane (BAPP), 1, 3-bis(4-aminophenoxy)benzene (TPE-R), 4,4-ox Cydianiline (ODA), m-bis (4-(4-aminophenoxy) phenyl) sulfone (m-BAPS) contains at least one, and
The dianhydride monomer is 4,4'-oxydiphthalic anhydride (ODPA), biphenyl-tetracarboxylic acid (BPDA), 4,4'-(4,4'-isopropylidene-diphenoxy) Method for manufacturing a bond ply layer for a flexible copper-clad laminate film comprising at least one of bis(phthalic anhydride) (BPADA).
delete According to claim 1,
In the step (c), a method of manufacturing a bond ply layer for a flexible copper-clad laminate film coating a thermoplastic polyimide resin to have a thickness smaller than that of the fluorine-based resin layer.
A fluorine-based resin layer surface-treated to have interfacial adhesion on both sides; And
Including; a thermoplastic polyimide resin layer coated on both surfaces of the surface-treated fluorine-based resin layer,
The thermoplastic polyimide resin has a viscosity of 50 to 20,000 cP at 25°C, and a weight average molecular weight of 1 x 10 ³ to 1 x 10 ⁶ ,
The thermoplastic polyimide resin includes a diamine monomer, a dianhydride monomer, and a monomer for reducing dielectric constant,
The dielectric constant reduction monomer is a poly-diaminosiloxane (PSX), a bond ply layer for a flexible copper-clad laminate film comprising at least one of dimer diamine.
The method of claim 6,
The diamine monomer is 2,2-bis(4-(4-amino phenoxy)phenyl)propane (BAPP), 1, 3-bis(4-aminophenoxy)benzene (TPE-R), 4,4-ox Cydianiline (ODA), m-bis (4-(4-aminophenoxy) phenyl) sulfone (m-BAPS) contains at least one, and
The dianhydride monomer is 4,4'-oxydiphthalic anhydride (ODPA), biphenyl-tetracarboxylic acid (BPDA), 4,4'-(4,4'-isopropylidene-diphenoxy) Bond ply layer for flexible copper-clad laminate films containing at least one of bis(phthalic anhydride) (BPADA).
delete The method of claim 6,
The bond ply layer for the flexible copper foil laminated film is a bond ply layer for a flexible copper foil laminated film having a tensile strength of 30 MPa or more, an elongation of 90% or more, and an elastic modulus of 600 MPa or more.
The method of claim 6,
The bond ply layer for the flexible copper foil laminated film is a bond fly layer for a flexible copper foil laminated film having a dielectric loss (D _f ) of less than 0.003 at 10 GHz and a dielectric constant (D _k ) of 3 or less at 10 GHz.

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