KR101375276B1 - Method of manufacturing laminated plate using thermoplastic polyimide adhesive film with excellent slip property - Google Patents

Abstract

Disclosed are a thermoplastic polyimide (TPI) adhesive film with improved slip properties, a laminated plate using the film, and a flexible printed circuit board using the laminated plate. The thermoplastic polyimide adhesive film according to the present invention has inert inorganic particles dispersed in thermoplastic polyimide, wherein 0.01-10 parts by weight of the inert inorganic particles is included relative to 100 parts by weight of the thermoplastic polyimide.

Description

Method for manufacturing laminate using thermoplastic polyimide adhesive film having excellent slip property {METHOD OF MANUFACTURING LAMINATED PLATE USING THERMOPLASTIC POLYIMIDE ADHESIVE FILM WITH EXCELLENT SLIP PROPERTY}

The present invention relates to a thermoplastic polyimide (TPI) adhesive film, and more particularly, to a thermoplastic polyimide adhesive film having excellent slip property, a laminate using the same, and a flexible circuit board using the laminate. .

Recently, flexible printed circuit boards (FPCBs) have been adopted as core boards of electronic products according to the weight reduction, miniaturization, and density of electronic devices using printed circuit boards (PCBs).

Flexible circuit boards are thin and easily bent due to the use of laminated plates made by attaching metal foil to the surface of the flexible insulating film as a base material, which enables three-dimensional wiring, which is advantageous for miniaturization and weight reduction of devices.

The flexible printed circuit board may be composed of a single layer, or a multilayer such as two layers, three layers, etc., and as the structure and function of electronic product products are diversified, the use of flexible printed circuit boards having multiple layers is increasing.

As an insulating film for a flexible circuit board, a polyimide (PI) film coated with a thermoplastic polyimide (TPI) film on one or both surfaces is mainly used.

As a method of manufacturing a flexible circuit board, a sputtering method, a cast method of imidizing after coating and applying polyamic acid, which is a precursor of polyimide, onto a metal foil, and forming a polyimide film by plating The metalizing method which directly installs a metal layer in the inside, and the lamination method which overlaps and attaches a polyimide film and metal foil by heating and pressurization are mentioned.

Among these, the lamination method is excellent in that the thickness range of the applicable metal foil is wider than the cast method, and the apparatus cost is lower than the metallizing method. As a laminating apparatus, a hot roll laminating apparatus or a double belt press apparatus for continuously laminating while releasing a roll-shaped material is used, but in terms of productivity, the hot roll laminating method is more preferably used. Can be.

However, when the thermal roll lamination method is used, there is a high possibility of scratches and curls due to friction between the metal roll and the thermoplastic polyimide film due to the low slippage property of the thermoplastic polyimide film.

Prior art related to the present invention is Korean Patent Laid-Open Publication No. 2008-0012527 (published Feb. 12, 2008), which discloses a flexible circuit board having a mesh ground copper foil layer.

SUMMARY OF THE INVENTION An object of the present invention is to provide a thermoplastic polyimide adhesive film having excellent slip properties, and to provide a laminate that can improve scratch resistance and anti-wrinkle properties, and a flexible circuit board including the laminate.

Thermoplastic polyimide (TPI) adhesive film according to the present invention for achieving the above object is inert inorganic particles are dispersed in a thermoplastic polyimide, the inert inorganic particles are 0.01 to 100 parts by weight of the thermoplastic polyimide, It is characterized by being included in ˜10 parts by weight.

Laminated according to the present invention for achieving the above object is an adhesive film formed with a thermoplastic polyimide adhesive film on one or both sides of the thermosetting polyimide film; And a metal foil formed on the thermoplastic polyimide adhesive film, wherein the thermoplastic polyimide adhesive film is formed by dispersing 0.01 to 10 parts by weight of inert inorganic particles in 100 parts by weight of the thermoplastic polyimide.

Laminated sheet manufacturing method according to the present invention for achieving the above object is a sheet of thermosetting on the outside of the metal foil, the adhesive film is laminated with a thermoplastic polyimide adhesive film on one side or both sides of the thermosetting polyimide film, and the metal foil is laminated from above Disposing an adhesive film and two sheets of metal foil on which one side or both sides of the polyimide film are laminated a thermoplastic polyimide adhesive film; And heating and compressing the adhesive film having the thermoplastic polyimide adhesive film laminated on one or both sides of the thermosetting polyimide film and the metal foil by a thermal roll lamination method, wherein the thermoplastic polyimide adhesive film is a thermoplastic polyimide. 0.01 to 10 parts by weight of the inert inorganic particles are dispersed per 100 parts by weight.

A flexible printed circuit board (FPCB) according to the present invention for achieving the above object is characterized in that it comprises at least one layer of the laminate.

The present invention can provide a thermoplastic polyimide adhesive film having excellent slip property by dispersing inert inorganic particles in thermoplastic polyimide to improve surface roughness.

In addition, the present invention is to reduce the friction between the metal roll and the thermoplastic polyimide adhesive film during the process run by using a thermoplastic polyimide adhesive film excellent in slip properties, it is possible to prevent the occurrence of scratches, one or both sides of the thermosetting polyimide film It can prevent the wrinkles which may occur when winding up the adhesive film in which the thermoplastic polyimide adhesive film is laminated | stacked in the roll state.

In addition, the present invention can provide a flexible circuit board without deterioration of electrical properties, including a laminated plate having excellent scratch resistance and anti-wrinkle resistance, and thereby can achieve high functionalization and long life of various electronic devices.

1 is a cross-sectional view showing a laminated plate to which a thermoplastic polyimide adhesive film according to an embodiment of the present invention is applied.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention, and how to achieve them, will be apparent from the following detailed description of embodiments and drawings.

The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. To fully disclose the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims.

Hereinafter, a thermoplastic polyimide (TPI) adhesive film having excellent slip properties according to the present invention, a laminated plate using the same, and a flexible printed circuit board including the laminated plate; FPCB) is explained in full detail.

The thermoplastic polyimide (TPI) adhesive film according to the present invention may be used as an adhesive in a laminate for a flexible printed circuit board (FPCB), and the like, and may include inert inorganic particles as an additive to the thermoplastic polyimide.

Inert inorganic particles in the present invention is added to improve the slip properties of the thermoplastic polyimide adhesive film produced. When the inert inorganic particles are added, the centerline average roughness (Ra) of the thermoplastic polyimide adhesive film to be manufactured is increased, thereby improving slip performance.

Such inert inorganic particles are preferably dispersed at 0.01 to 10 parts by weight based on 100 parts by weight of the thermoplastic polyimide. At this time, when the content of the inert inorganic particles is less than 0.01 parts by weight, the addition effect may be insufficient. On the other hand, when the content of the inert inorganic particles exceeds 10 parts by weight, the flexibility of the thermoplastic polyimide adhesive film may be lowered.

In addition, the average particle diameter of the inert inorganic particles may be in the range of 50 to 1000 nm, preferably 100 to 500 nm. When the average particle diameter of the inert inorganic particles is less than 50 nm, expression of a modifying effect such as slippage due to improvement in center line average roughness Ra may not be sufficient. On the other hand, when the average particle diameter of the inert inorganic particles exceeds 1000 nm, excessive roughness may be formed in the thermoplastic polyimide adhesive film, which may cause problems such as imprinting when laminated with a metal foil such as copper foil.

For example, silica (Silica, SiO ₂ ) may be used as the inert inorganic particles, and the shape of the silica is not particularly limited, and for example, a silica such as a spherical shape, a needle shape, a cubic shape, and a scaly shape may be used. . It is preferable to use spherical silica in consideration of the surface property of the thermoplastic polyimide adhesive film.

 The thermoplastic polyimide used in the present invention may be prepared using polyamic acid as a precursor.

The thermoplastic polyimide has excellent melt processability and high mechanical properties such as high stability and frictional resistance to heat and chemicals, low thermal expansion rate, and the like, so that the thermoplastic polyimide can be used in processes up to 230 ° C.

The kind of the thermoplastic polyimide may use a known material without particular limitation, and for example, the thermoplastic polyimide may be a thermoplastic polyamide imide, a thermoplastic polyether imide, and a thermoplastic polyester imide. (polyester imide) may include one or more.

In addition, in order to enable the existing laminate (laminate), and not impair the heat resistance of the laminate to be produced, in the present invention, the thermoplastic polyimide preferably has a glass transition temperature (Tg) in the range of 150 ~ 300 ℃.

The polyamic acid, which is a precursor of the thermoplastic polyimide adhesive film used in the present invention, is not particularly limited, and any polyamic acid can be used. As a method for producing a polyimide film from a polyamic acid solution, a conventional known method can be used. This method includes a thermal imidation method and a chemical imidization method.

For example, in the present invention, a polyamic acid solution that is a precursor of the thermoplastic polyimide may be prepared by adding a solid component consisting of a diamine compound and a dianhydride compound to an organic solvent.

The diamine compound may be, for example, 4,4'-oxydianiline (ODA), 1,3-bis (4-aminophenoxyl) benzene (1,3'-Bis (4-aminophenoxyl ) Benzene; TPE-R), 2,2-bis (4- (4-aminophenoxy) -phenyl) propane (2,2-Bis (4- (4-aminophenoxy) -phenyl) propane; BAPP) It may be presented, and may include one or more of these.

The dianhydride compound may be, for example, pyromellitic dianhydride (PMDA), 3,3 ', 4,4'-biphenyl tetracarboxylic dianhydride (3,3'4,4' -Biphenyl tetracarboxylic dianhydride; BPDA), 4,4'-oxydiphtahlic anhydride (ODPA), 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride (3,3 ', 4,4'-benzophenonecarboxylic dianhydride; BTDA) and the like, and may include one or more of them.

The organic solvent is N-methyl-2-pyrrolidone (NMP), N, N-dimethyl acetamide (N, N-Dimethyl-acetamide; DMAc), N, N-dimethylform Amide (N, N-dimethylformamide; DMF), dimethyl sulfoxide (DMSO) and the like can be used, and may include one or more of them.

On the other hand, the thickness of the thermoplastic polyimide adhesive film according to the present invention is not particularly limited, but may have a range of about 1 ~ 10㎛ in consideration of the thickness of the laminate to be manufactured.

The thermoplastic polyimide adhesive film according to the present invention has a low coefficient of friction of less than or equal to a centerline average roughness (Ra) of 100 nm and a range of 0.1 to 0.5 by dispersing inert inorganic particles such as silica in the thermoplastic polyimide. Therefore, the thermoplastic polyimide adhesive film according to the present invention may have excellent slipability.

In addition, the present invention can provide a laminate using the aforementioned thermoplastic polyimide adhesive film, preferably a flexible metal foil laminate, and more preferably a flexible copper clad laminate (FCCL).

1 is a cross-sectional view showing a laminated plate to which a thermoplastic polyimide adhesive film according to an embodiment of the present invention is applied.

As shown in FIG. 1, the laminate according to an embodiment of the present invention includes an adhesive film 125 and a thermoplastic polyimide adhesive film 120 having a thermoplastic polyimide adhesive film 120 formed on both sides of a thermosetting polyimide film 110. It may include a metal foil 130 formed on). Meanwhile, the thermoplastic polyimide adhesive film 120 may be formed only on one surface of the thermosetting polyimide film 110, unlike FIG. 1.

In this case, since the thermoplastic polyimide adhesive film 120 is the same as described above, a duplicate description thereof will be omitted, and only the remaining components except for this will be described.

In the present invention, the material of the thermosetting polyimide film 110 as a substrate interposed between the thermoplastic polyimide adhesive films 120 may use a known material without particular limitation.

The thickness of the thermosetting polyimide film 110 is not particularly limited, but may have a range of about 5 ~ 50㎛ in consideration of the thickness of the laminate to be manufactured.

In this case, the thermosetting polyimide film 110 and the thermoplastic polyimide adhesive film 120 constitute an original plate of the laminate.

The metal foil 130 is not particularly limited as long as it is a metal having conductivity and ductility. For example, the metal foil 130 may be formed of any one of copper (Cu), tin (Sn), gold (Au), and silver (Ag), and preferably may be formed of copper (Cu). If the metal foil 130 is a copper film, it may be a rolled copper foil or an electrolytic copper foil.

The thickness of the metal foil 130 is not particularly limited, but may be in the range of about 5 to 40 μm, preferably about 9 to 35 μm. At this time, when the thickness of the metal foil 130 is less than 5㎛, the conductivity may be insufficient. On the other hand, when the thickness of the metal foil 130 exceeds 40㎛, it may be difficult to impart ductility to the laminate to be manufactured.

According to the present invention, a method of manufacturing the above-described laminate is as follows, but is not limited thereto.

For a preferred embodiment of the laminated plate manufacturing method, a sheet of thermosetting polyimide film outside the chamber such that the metal foil, the adhesive film in which the thermoplastic polyimide adhesive film is laminated on one or both sides of the thermosetting polyimide film, and the metal foil are laminated from above. Disposing an adhesive film and two metal foils on which one side or both sides of the thermoplastic polyimide adhesive film are laminated; And heating and compressing the adhesive film having the thermoplastic polyimide adhesive film laminated on one or both sides of the thermosetting polyimide film and the metal foil by a thermal roll lamination method, wherein the thermoplastic polyimide adhesive film is a thermoplastic polyimide. 0.01 to 10 parts by weight of the inert inorganic particles are dispersed per 100 parts by weight.

The hot roll lamination process may be carried out in a roll to roll process at a temperature of 300 ~ 400 ℃. At this time, the tension of the metal foil can be adjusted to 50 ~ 1000N / m, the tension of the adhesive film can be adjusted to 0.1 ~ 100N / m. In addition, the incident angle of a metal foil can be adjusted to 10-80 degrees.

Through the adjustment of the tension and the angle of incidence, it is possible to prevent the generation of wrinkles in the laminate and to improve the dimensional stability. However, when the tension is less than the above-mentioned range, winding may be difficult, and it may be difficult to obtain a laminate having a good appearance. On the other hand, if the above range is exceeded, the dimensional stability may be lowered.

At the time of hot roll lamination, the metal foil and the thermoplastic polyimide adhesive film wound on each winding roll are heated to form a laminated plate having the structure shown in FIG. 1 while passing between a pair of pressing rolls.

In this process, since the thermoplastic polyimide adhesive film having excellent slip properties due to the improvement of the centerline average roughness (Ra) has a low friction force between the crimping roll and the thermoplastic polyimide adhesive film, the laminate can be easily formed without scratches and wrinkles. have.

Furthermore, the present invention provides a flexible printed circuit board (FPCB) comprising the above-described laminate. The flexible circuit board is completed by forming a circuit through etching or the like in the above-described laminate, for example, may be a multi-layer flexible circuit board including at least one layer of the above-described laminate.

Since the flexible circuit board has no deterioration in electrical characteristics through improvement of scratch resistance and anti-wrinkle properties due to the thermoplastic polyimide adhesive film having excellent slip property among the laminated boards, it is possible to achieve high functionality and long life of various electronic devices. Can be.

Example

Hereinafter, the configuration and operation of the present invention through the preferred embodiment of the present invention will be described in more detail. It is to be understood, however, that the same is by way of illustration and example only and is not to be construed in a limiting sense.

Details that are not described herein will be omitted since those skilled in the art can sufficiently infer technically.

1. Manufacture of thermoplastic polyimide adhesive film

Thickness thermoplastic polyimide adhesive film specimens according to Examples 1 to 3 and Comparative Example 1 were prepared under the conditions shown in Table 1 below.

At this time, the thermoplastic polyimide adhesive film is N-methyl-2-pi 70% by weight ODA, 20% by weight TPE-R, 10% by weight BAPP diamine compound and 20% by weight PMDA, 80% by weight dianhydride compound The polyamic acid synthesized by polymerization in a rollidone (NMP) solvent was applied to both sides of the thermosetting polyimide film and dried. And it manufactured by the thermal imidation method at 300 degreeC.

2. Property evaluation

(1) slip

The slipperiness of the upper and lower surfaces of the thermoplastic polyimide adhesive film was measured using a HEIDON STATIC FRICTION TESTER measuring device to measure the angle at which the thermoplastic polyimide adhesive film began to slip.

(2) coefficient of friction

The coefficients of friction of the upper and lower surfaces of the thermoplastic polyimide adhesive film were measured using a HEIDON STATIC FRICTION TESTER measuring device, and the coefficient of friction when the thermoplastic polyimide adhesive film began to slip.

(3) surface roughness

The centerline average roughness (Ra) of the surface of the thermoplastic polyimide adhesive film was measured using the 3-dimensional surface roughness measuring instrument of KOSAKA, Japan.

Physical properties according to Examples 1 to 3 and Comparative Example 1 are shown in Table 1.

[Table 1]

Referring to Table 1, all of Examples 1 to 3 of the present invention exhibited excellent physical properties in terms of basic physical properties, such as slip properties, coefficient of friction and surface roughness properties required as a flexible copper foil laminate.

On the other hand, Comparative Example 1 without addition of silica showed very poor physical properties in terms of slip properties, coefficient of friction and surface roughness.

In addition, it was found that the slip properties, the coefficient of friction and the centerline average roughness Ra were improved in proportion to the addition amount of silica and the average particle diameter of silica.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood by those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

110: thermosetting polyimide film
120: thermoplastic polyimide adhesive film
125: adhesive film
130: metal foil

Claims (12)

delete delete delete delete delete delete delete delete delete delete Disposing a metal foil, an adhesive film having a thermoplastic polyimide adhesive film laminated on one or both sides of a thermosetting polyimide film, and one adhesive film and two metal foils outside the chamber so that the metal foil is laminated; And
And heating and compressing the metal foil, the adhesive film, and the metal foil by a hot roll lamination method.
The thermoplastic polyimide adhesive film is dispersed in 0.01 to 10 parts by weight of inert inorganic particles having an average particle diameter of 100 to 500 nm with respect to 100 parts by weight of thermoplastic polyimide, and has a centerline average roughness (Ra) of 21 nm or more and 100 nm or less, and friction Coefficient is 0.1-0.5,
The hot roll laminating method is carried out at a temperature of 300 ~ 400 ℃, the tension of the metal foil is adjusted to 50 ~ 1000N / m, the tension of the adhesive film is adjusted to 0.1 ~ 100N / m, the of the metal foil to the roll Laminated sheet manufacturing method characterized in that carried out by a roll to roll process in which the incident angle is adjusted to 10 ~ 80 °. delete

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