KR101516872B1 - Insulating resin sheet for flexible printed circuit board and method of manufacturing the same, and printed circuit board comprising the same - Google Patents

Abstract

The present invention relates to a polyimide film; And an insulating resin layer formed on the upper and lower surfaces of the polyimide film, the insulating resin layer being capable of forming a roughness by a desmearing process, and a method for producing the same, And a method of manufacturing the same.
The present invention can provide a flexible printed circuit board capable of reducing the total stacking thickness and increasing the degree of design freedom of the substrate while realizing a high density fine circuit pattern.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insulating resin sheet for forming a flexible printed circuit board, a method of manufacturing the same, and a printed circuit board including the same. BACKGROUND OF THE INVENTION 1. Field of the Invention [0001]

The present invention relates to an insulating resin sheet for forming a flexible printed circuit board capable of reducing the total lamination thickness and enhancing the flexibility of a substrate and improving freedom of product design, a high density fine circuit pattern, and a method for manufacturing the same, And a method of manufacturing the same.

Flexible printed circuit boards (FPCB) are excellent in heat resistance, bending resistance and chemical resistance, and are less deformed in dimension, and are widely used in a bent portion of a folding cellular phone, a driving unit of a digital camera, and an LCD.

In recent years, there has been a demand for improvement in flex life, flexibility, and high-density packaging due to the trend of thin and small size of electronic products and miniaturization and high level of electronic devices. Recently, Narrow pitch and high density mounting are progressing, and the required level of mechanical properties for the laminated board is higher than ever, and the demand for non-adhesive polyimide copper-clad laminate, which is also flexible for printed circuit boards, is increasing.

The flexible copper-clad laminate is a material of a flexible printed circuit board (FPCB), which can be divided into an adhesive three-layer substrate and a non-adhesive two-layer substrate. A method for manufacturing an adhesive type three-layer substrate is mainly to bond a polyimide film and a copper foil using an adhesive. A non-adhesive double-layer substrate is produced by first coating a polyimide solution on a surface of a copper foil and changing the polyimide solution into a polyimide solution through a high temperature chemical reaction to form a one-layer polyimide layer on the surface of the copper foil. Compared to the adhesive three-layer substrate, the non-adhesive two-layer substrate is widely used because of its thin, long-lasting strength. In addition, as many electronic products have become sophisticated and miniaturized, a non-adhesive type double-sided flexible copper-clad laminate has been produced.

However, in the conventional flexible copper-clad laminates, the thickness of the copper foil and the polyimide film is too thin, so that there is a high risk of defects in the heat lamination. Further, defective joints (bubbles, wrinkles, center defects, etc.) frequently occur due to differences in thickness and tension of the copper foil and the polyimide film. In addition, there is a problem that the polyimide is melted out at the time of the hot press or the high-temperature heat treatment to pollute the environment, and the polyimide film coated with the thermoplastic polyimide (TPI) has a disadvantage of increasing the production cost have. In addition, conventional flexible copper clad laminate and polyimide film layers are difficult to form a fine circuit pattern due to disadvantages of roughness formation and subsequent plating formation in a manufacturing process such as a desmear process.

SUMMARY OF THE INVENTION The present invention has been conceived in order to solve the above-mentioned problems, and it is an object of the present invention to provide a flexible polyimide film and an insulating resin sheet, The present inventors have realized that not only a printed circuit board is easily manufactured but also the bonding strength between the insulating resin layer and the plated copper foil layer is improved and at the same time the entire laminated layer thickness is reduced and a fine circuit pattern is realized,

Accordingly, it is an object of the present invention to provide an insulating resin sheet for forming a flexible laminated printed circuit board which can provide flexibility to a substrate, increase the degree of freedom of product design, and enable roughness formation by a desmear treatment.

The present invention also provides a printed circuit board which can reduce defects in the circuit formation process and simultaneously exhibit a reduction in the thickness of the laminate, an interlaminar bond strength, a heat resistance and a long-term reliability improvement by including the insulating layer formed using the above- And a method for producing the same.

The present invention relates to a polyimide film; And an insulating resin layer formed on the upper and lower surfaces of the polyimide film, the insulating resin layer being capable of forming a roughness by a desmearing process.

According to a preferred embodiment of the present invention, the insulating resin layer comprises (a) polyphenylene ether in combination with 9,9-bis (hydroxyaryl) fluorene (BCF) or 9,10-dihydro- (Dihydroxyaryl) -10-phosphaphenanthrene 10-oxide (HCA-HQ); (b) an epoxy resin; (c) a curing agent; And (d) at least one modified epoxy resin selected from the group consisting of a dimer acid-modified epoxy resin, a urethane-modified epoxy resin and a carboxyl-terminated butadiene acrylonitrile (CTBN) will be. When the thermosetting resin composition comprises a polyphenylene ether modified resin (a) obtained by redispersing polyphenylene ether in the presence of 9,9-bis (hydroxyaryl) fluorene (BCF), (e) .

Here, the polyphenylene ether-modified resin (a) may be modified to have a lower molecular weight than the high molecular weight polyphenylene ether resin through a redistribution reaction so that a high molecular weight polyphenylene ether resin having a number average molecular weight in the range of 10,000 to 30,000, It is preferable that the redistribution reaction is carried out in the presence of a radical initiator, a catalyst, or a radical initiator in the presence of a catalyst having an average molecular weight in the range of 1,000 to 15,000.

The modified epoxy resin (d) preferably has an epoxy equivalent of 100 to 500 g / eq and a viscosity of 5,000 to 30,000 cps. The epoxy resin (b) preferably contains two or more kinds of epoxy resins different in epoxy equivalent. .

Wherein the resin composition for forming an insulating resin layer comprises: (a) 10 to 60 parts by weight of a polyphenylene ether modified resin; (b) 10 to 40 parts by weight of an epoxy resin; (c) 10 to 40 parts by weight of a curing agent; And (d) 5 to 40 parts by weight of a modified epoxy resin, wherein the polyphenylene ether-modified resin (a) contains polyphenylene ether in the presence of 9,9-bis (hydroxyaryl) fluorene (BCF) (E) in the range of 5 to 40 parts by weight based on 10 to 60 parts by weight of the polyphenylene ether modified resin.

According to a preferred embodiment of the present invention, the thickness of the polyimide film is in the range of 5 탆 to 100 탆, and the thickness of the insulating resin layer formed on the upper and lower surfaces of the polyimide film is preferably in the range of 1 탆 to 50 탆.

According to a preferred embodiment of the present invention, a support layer may be further included on the insulating resin layer, and further, a release layer may be further provided between the insulating resin layer and the support layer.

The present invention also provides a non-adhesive type flexible copper-clad laminate (FCCL) formed using the above-described insulating resin sheet and a printed circuit board comprising the same.

According to a preferred embodiment of the present invention, the flexible copper-clad laminate (FCCL) comprises the insulating resin sheet; And a copper foil layer formed on the upper and lower surfaces of the insulating resin layer of the insulating resin sheet, respectively.

According to another preferred embodiment of the present invention, the printed circuit board (FPCB) comprises an insulating resin sheet; A copper foil plating layer formed on the upper and lower surfaces of the insulating resin layer of the insulating resin sheet and having a predetermined pattern; And a plurality of through holes formed to penetrate the insulating resin sheet and plated to electrically connect the patterns of the copper foil layer formed on the upper and lower surfaces. Here, the line / space (L / S) of the circuit pattern may range from 2 탆 / 2 탆 to 30 탆 / 30 탆.

In addition, the present invention provides a method for producing the above-described insulating resin sheet.

According to a preferred example of the present invention, the manufacturing method comprises the steps of: (i) coating a first surface of a polyimide film with a thermosetting resin composition forming the insulating resin layer and then drying the thermosetting resin composition; (Ii) coating and drying the thermosetting resin composition on the second side of the polyimide film; And (iii) drying the double-side-coated polyimide film and curing the composition.

According to another preferred embodiment of the present invention, there is provided a method for producing a thermosetting resin composition, comprising the steps of (i) providing a first adhesive sheet coated with a thermosetting resin composition for forming an insulating resin layer on a first surface of a first support, Preparing a second adhesive sheet onto which the thermosetting resin composition is applied, respectively; And (ii) a first adhesive sheet and a second adhesive sheet are laminated on the upper and lower surfaces of the polyimide film, respectively, wherein the composition layer for forming the insulating resin layer is disposed so as to be in contact with the polyimide film, ≪ / RTI > to cure the composition.

In addition, the present invention provides a method of manufacturing a printed circuit board using the above-described insulating resin sheet.

According to a preferred embodiment of the present invention, the manufacturing method comprises the steps of: (i) forming at least one hole in the above-described insulating resin sheet; (Ii) desmearing the surface and the inside of the film to form roughness; (Iii) forming an electroless plating layer on the rough surface and the hole inner surface of the film; (Iv) forming a pattern on the formed electroless plating layer using a photoresist; (v) forming a circuit layer by electrolytic plating on the pattern; And (vi) peeling the photoresist and removing the exposed electroless plating layer.

In the present invention, since an insulating resin sheet in which a polyimide film capable of imparting flexibility of a substrate and an insulating resin layer capable of forming an illuminance by a desmearing process are sequentially laminated is used, a fine circuit is formed It is possible to realize a more precise circuit by significantly reducing the micro-crack occurrence rate of the insulating layer.

Further, by applying the polyimide film, flexibility can be imparted to the substrate, and the degree of freedom in product design can be increased.

Further, the thickness of the flexible printed circuit board can be remarkably reduced, and the structural deflection characteristic as a final product can be minimized, thereby ensuring ease of manufacture.

1 is a cross-sectional view showing a configuration of an insulating resin sheet according to an embodiment of the present invention.
2 is a cross-sectional view showing a configuration of an insulating resin sheet according to another embodiment of the present invention.
3 is a cross-sectional view illustrating a manufacturing process of a printed circuit board according to an embodiment of the present invention.
4 is a scanning electron microscope (SEM) surface photograph of the insulating resin sheet produced in Example 1 after desmear treatment.
5 is a scanning electron microscope (SEM) surface photograph of the insulating resin sheet prepared in Comparative Example 1 after desmear treatment.
6 is a scanning electron microscope (SEM) surface photograph of the insulating resin sheet produced in Example 5 after desmear treatment.
7 is a scanning electron microscope (SEM) surface photograph of the insulating resin sheet produced in Comparative Example 4 after desmear treatment.
Description of the Related Art
100: Insulation resin sheet for forming a flexible circuit board
110: polyimide film 120: insulating resin layer
130: release layer 140: support layer

Hereinafter, the present invention will be described in detail.

The present invention is characterized by providing an insulating resin sheet for forming a flexible printed circuit board (FPCB) capable of improving the degree of freedom in product design so as to freely form a structure, a pattern, and the like of a printed circuit board do.

(I) a polyimide film; And (ii) an insulating resin layer formed on the upper and lower surfaces of the polyimide film, the insulating resin layer being capable of forming a roughness by a desmearing process, respectively (see FIG. 1).

Here, since the insulating resin layer is a resin layer which does not contain an inorganic filler or contains a very small amount, the generation rate of micro-cracks in the laser processing step during the manufacturing process of a printed circuit board is significantly reduced, Circuit implementation is possible. In addition, since the soluble material capable of forming the roughness by the desmearing process is included, the bonding strength between the rough surface of the insulating resin layer and the plated copper foil layer formed by the subsequent plating process can be improved.

In addition, since the insulating resin sheet of the present invention is made of polyimide (PI) film having flexibility, the degree of freedom of product design can be increased. In addition, it is possible to simultaneously reduce the total thickness, impart flexibility of the substrate, and realize a high-density fine circuit pattern.

<Insulating resin sheet for forming a flexible printed circuit board>

Hereinafter, an insulating resin sheet for forming a flexible printed circuit board (FPCB) according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1, the insulating resin sheet 100 according to the present invention includes a polyimide film 110 and an insulating resin layer 120 disposed on the upper and lower surfaces of the polyimide film, respectively, As shown in Fig.

<Polyimide (PI) Film>

In the insulating resin sheet of the present invention, the polyimide film 110 not only serves as a base supporting film for physically supporting the insulating resin sheet, but also has a high heat resistance and flexibility, have. At this time, the polyimide film contains an inorganic filler if necessary, and the coefficient of thermal expansion (CTE) of the substrate can be controlled.

The polyimide (PI) resin is a polymer material having an imide ring, and exhibits excellent heat resistance, ductility, chemical resistance, abrasion resistance and weather resistance based on the chemical stability of the imide ring. Thermal expansion rate, low air permeability and excellent electrical properties.

The polyimide film may be in the form of a film or sheet having a self-supporting property. In this case, a commercially available polyimide film may be used, or a diamine compound and a tetracarboxylic acid compound may be condensed according to a method known in the art, and then the reaction product may be coated on a substrate and dried / cured .

The thickness of the polyimide film can be appropriately adjusted in consideration of handling property of the film, physical rigidity, thermal expansion coefficient, thinning of the substrate, high-density wiring, and the like. For example, in the range of 5 to 100 mu m, preferably in the range of 12.5 to 50 mu m, and more preferably in the range of 12.5 to 25 mu m. The surface of the polyimide film may be subjected to a surface treatment such as a mat treatment or a corona treatment.

In order to effectively reduce the difference in the coefficient of thermal expansion (CTE) between the polyimide film layer and the copper foil layer to effectively improve the warping property, the low expansion, the mechanical properties, and the low stress of the final product, the polyimide film layer And may contain conventional inorganic fillers. Non-limiting examples of usable inorganic fillers include inorganic fillers such as silica, calcium carbonate, magnesium carbonate, alumina, magnesia, clay, talc, calcium silicate, titanium oxide, antimony oxide, glass fiber, aluminum borate, strontium titanate, calcium titanate , Magnesium titanate, bismuth titanate, titanium oxide, barium zirconate, calcium zirconate, boron nitride, silicon nitride, talc, mica and the like. The amount of the inorganic filler to be used is not particularly limited, and can be appropriately adjusted in consideration of the above-described flexural characteristics, mechanical properties, and the like.

The polyimide (PI) film according to the present invention may contain a laser energy absorbing component in order to further improve the workability of the hole by the laser. As the laser energy absorbing component, a known one such as carbon powder, metal compound powder, metal powder or black dye can be used. In addition, any one of them or two or more of them may be used in combination.

Examples of the carbon powder include powders of carbon black such as furnace black, channel black, acetylene black, thermal black and anthracene black, graphite powder, and mixtures thereof. Examples of the metal compound include titania such as titanium oxide, magnesia such as magnesium oxide, iron oxide such as iron oxide, nickel oxide such as nickel oxide, zinc oxide such as manganese dioxide and zinc oxide, silicon dioxide, aluminum oxide, Cobalt oxide such as cobalt oxide, tin oxide such as tin oxide, tungsten oxide such as tungsten oxide, silicon carbide, tungsten carbide, boron nitride, silicon nitride, titanium nitride, aluminum nitride, barium sulfate, rare earth oxides, Powder and the like. Examples of the metal powder include powders of silver, aluminum, bismuth, cobalt, copper, iron, magnesium, manganese, molybdenum, nickel, palladium, antimony, silicon, tin, titanium, vanadium, tungsten, zinc, . The laser energy absorbing component is preferably a carbon powder from the viewpoint of conversion efficiency with respect to heat of laser energy, versatility and the like. The upper limit of the average particle diameter of the laser energy absorbing component is preferably in the range of 0.01 mu m to 20 mu m from the viewpoint of efficiently absorbing the laser energy.

On the other hand, in the present invention, a polyimide (PI) film is mainly described as a base support film, but it is not particularly limited as long as it is a resin film having other heat resistance, flexibility, smoothness and low water absorption. For example, it is possible to use a polyethylene terephthalate (PET) film, a polyethylene naphthalate film, a polyamideimide film, a polyamide film, a polytetrafluoroethylene film, a polycarbonate film or a mixture of two or more thereof It is also within the scope of the present invention to use conventional plastic films known to those skilled in the art.

<Insulating resin layer>

In the insulating resin sheet of the present invention, the insulating resin layer 120 is disposed on the upper and lower surfaces of the polyimide film 110, and is formed by curing a thermosetting resin composition capable of forming roughness by a desmearing process .

The resin composition of the present invention for forming the above-described insulating resin layer is prepared by (a) mixing polyphenylene ether with 9,9-bis (hydroxyaryl) fluorene (BCF) or 9,10-dihydro- A polyphenylene ether modified resin obtained by a redistribution reaction in the presence of -10- (dihydroxyaryl) -10-phosphapenanthrene 10-oxide (HCA-HQ); (b) an epoxy resin; (c) a curing agent; (d) at least one modified epoxy resin selected from the group consisting of dimeric acid-modified epoxy resins and urethane-modified epoxy resins. When the thermosetting resin composition is a polyphenylene ether modified resin (a) in which polyphenylene ether is redistributed and reacted in the presence of 9,9-bis (hydroxyaryl) fluorene (BCF), the flame retardant (e) As shown in FIG.

(a) a polyphenylene ether (PPE) modified resin

The first component constituting the thermosetting resin composition for forming an insulating resin layer according to the present invention is a polyphenylene ether modified resin (a).

Conventionally, when modifying a high molecular weight polyphenylene ether with a low molecular weight polyphenylene ether resin, a compound such as a phenol derivative or bisphenol A is generally used. In this case, the molecular structure is rotatable and the dielectric constant is lowered .

However, in the present invention, a 9,9-bis (hydroxyaryl) fluorene (BCF) or 9,10-dihydro-9-oxa-10- (dihydroxyaryl) By modifying a high molecular weight polyphenylene ether with a low molecular weight polyphenylene ether resin using 10-phosphaphenanthrene 10-oxide (HCA-HQ), the solubility is improved and film coating becomes easy, It blocks rotation in the molecular structure and introduces a large number of hydrophobic double ring hydrocarbon groups, thereby reducing the electron polarization and lowering the dielectric constant. In addition, in comparison with conventional phenol derivatives and bisphenol A, 9,9-bis (hydroxyaryl) fluorene (BCF) or 9,10-dihydro-9-oxa-10- (dihydroxyaryl) Since the molecular structure of nhenthrene 10-oxide (HCA-HQ) is bulky and the crystallinity is high, it is possible to improve the properties of the glass transition temperature (Tg) of the low molecular weight modified polyphenylene ether modified resin .

Further, the hygroscopic property can be enhanced by the increase of the hydrophobic group, and the crosslinking property can be strengthened, so that the thermal property and the chemical resistance property can be enhanced. By improving the dielectric properties, low dielectric and low loss substrates can be realized. Particularly, in the case of a desmear process for forming a microcircuit, the chemical resistance of the insulating layer is important because it is mostly composed of an acid / alkali process. In the present invention, the polyphenylene ether-modified resin (PPE) modified with BCF or HCA-HQ has a high degree of crosslinking to enhance the chemical resistance and low surface roughness (Ra).

In addition, the polyphenylene ether (PPE) modified resin having the self-extinguishing property due to the phosphorus (P) component contained in the HCA-HQ molecule has a flame retardant property by itself. As a result, it is possible to develop a microcircuit pattern material having excellent flame retardancy without adding a separate flame retardant.

Accordingly, the insulating resin sheet and the printed circuit board manufactured using the resin composition of the present invention have an advantage of improving physical properties such as moldability, workability, dielectric properties, heat resistance, and adhesive strength.

In the present invention, the polyphenylene ether to be modified may be a high molecular weight polyphenylene ether. For example, a polyphenylene ether having a number average molecular weight (Mn) of 10,000 to 30,000 may be used. Further, it is not particularly limited as long as the main skeleton is polyphenylene ether. The molecular weight of the low molecular weight modified polyphenylene ether modified resin by redistribution of the high molecular weight polyphenylene ether resin is not particularly limited, but may be, for example, in the range of 1,000 to 15,000.

The 9,9-bis (hydroxyaryl) fluorene (BCF) may be at least one compound selected from the group consisting of compounds represented by the following formulas (1) to (3)

In Formula (1), R ¹ to R ³ are each independently a C ₁ to C ₆ alkyl group; p1 is an integer of 1 to 5, q1 is an integer of 0 to 4, and p1 + q1 is an integer of 5 or less; k1 and k2 are each independently an integer of 0 to 4;

In Formula 2, R ⁴ to R ⁶ are each independently a C ₁ to C ₆ alkyl group; p2 is an integer of 1 to 4, q2 is an integer of 0 to 3, and p2 + q2 is an integer of 4 or less; k3 and k4 are each independently an integer of 0 to 4;

In Formula (3), R ⁷ to R ¹⁰ are each independently a C ₁ to C ₆ alkyl group; q3 and q4 are each independently an integer of 0 to 2, p3 + q3 is an integer of 3 or less, p4 + q4 is an integer of 4 or less, p3 is an integer of 1 to 3, p4 is an integer of 0 to 4, ; k5 and k6 are each independently an integer of 0 to 4;

In addition, the 9,10-dihydro-9-oxa-10- (dihydroxyaryl) -10-phosphapenanthrene 10-oxide (HCA-HQ) May be one or more compounds selected.

In Formula 4, R ¹¹ to R ¹³ are each independently a C ₁ to C ₆ alkyl group; p5 is 2, q5 is an integer of 0 to 3; k7 and k8 are each independently an integer of 0 to 4;

In Formula 5, R ¹⁴ to R ¹⁷ are each independently a C ₁ to C ₆ alkyl group; p6 and p7 are each independently an integer of 0 to 2, p6 + p7 is 2, p6 + q6 is an integer of 3 or less, and p7 + q7 is an integer of 4 or less; k9 and k10 are each independently an integer of 0 to 4;

(BCA) or 9,10-dihydro-9-oxa-10- (dihydroxyaryl) -10-phosphaphenanthrene 10-oxide (HCA-HQ ) Can be carried out in the presence of a radical initiator and / or catalyst.

As the radical initiator and the catalyst, those conventionally known in the art can be used. Examples of the radical initiator include t-butylperoxy isopropylmonocarbonate, t-butylperoxy 2-ethylhexylcarbonate, benzoyl peroxide, acetyl But are not limited to, acetyl peroxide, di-t-butyl peroxide, t-butyl peroxylaurate, t-butylperoxybenzoate, , But is not limited thereto. The radical initiator may be used in an amount of 0.1 to 5 parts by weight based on 10 to 60 parts by weight of the polyphenylene ether.

A non-limiting example of the catalyst is cobalt naphthanate. The catalyst may be used in an amount of 0.001 to 0.5 parts by weight based on 10 to 60 parts by weight of the polyphenylene ether.

The method of synthesizing a modified polyphenylene ether modified resin by redistribution of polyphenylene ether is not particularly limited and a conventional method known in the art can be applied. For example, polyphenylene ether and 9,9-bis (hydroxyaryl) fluorene (BCF) or 9,10-dihydro-9-oxa-10- (dihydroxyaryl ) -10-phosphaphenanthrene 10-oxide (HCA-HQ) and a radical initiator are mixed and heated to obtain a modified polyphenylene ether modified resin. At this time, the solvent may be a hydrocarbon-based solvent such as benzene or toluene, but is not particularly limited thereto. The reaction temperature and the reaction time can be appropriately controlled according to the number average molecular weight of the desired polyphenylene ether resin, and the reaction can be performed at 60 to 200 ° C for 10 minutes to 10 hours, for example.

In the thermosetting resin composition for forming an insulating resin layer according to the present invention, the content of the polyphenylene ether-modified resin (a) may be in the range of 10 to 60 parts by weight, preferably 20 to 40 parts by weight, Lt; / RTI &gt; When the content of the polyphenylene ether-modified resin falls within the above-mentioned range, the curing property, the molding processability and the adhesive force of the resin composition are good.

(b) Epoxy resin

The second component constituting the thermosetting resin composition for forming an insulating resin layer according to the present invention is an epoxy resin (b).

The epoxy resin may be any conventional epoxy resin known in the art, and it is preferable that two or more epoxy groups are present in one molecule.

Examples of usable epoxy resins include, but are not limited to, bisphenol A type / F type / S type resin, novolak type epoxy resin, alkylphenol novolak type epoxy resin, biphenyl type, aralkyl type, naphthol Naphthol type, dicyclopentadiene type, or mixed form thereof.

More specific examples thereof include epoxy resins such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, naphthalene type epoxy resin, anthracene epoxy resin, biphenyl type epoxy resin, Cresol novolak type epoxy resin, bisphenol A novolak type epoxy resin, bisphenol S novolak type epoxy resin, biphenyl novolac type epoxy resin, naphthol novolak type epoxy resin, naphthol phenol coaxial novolak type epoxy resin , Naphthol cholizole co-novolak type epoxy resin, aromatic hydrocarbon formaldehyde resin modified phenol resin type epoxy resin, triphenyl methane type epoxy resin, tetraphenyl ethane type epoxy resin, dicyclopentadiene phenol addition reaction type epoxy resin, phenol aral A quarternary epoxy resin, a polyfunctional phenol resin, a naphthol aralkyl type epoxy resin There is. At this time, the above-mentioned epoxy resin may be used alone, or two or more epoxy resins may be used in combination.

Particularly when a hydrogenated epoxy resin is used, it is preferable to use bisphenol A or biphenyl-type epoxy resin. In addition, when a resin having a high molecular weight is used in the epoxy resin, a greater ductility can be imparted to the insulating layer, so that adhesion characteristics between the laminated body and the metal after plating can be improved.

In order to further improve the adhesion properties after plating, two or more epoxy resins having different epoxy equivalents may be used in combination in the present invention. Preferably a first epoxy resin having an epoxy equivalent of 400 to 1,000 g / eq; And a second epoxy resin having an epoxy equivalent of 100 to 300 g / eq at a weight ratio of 50 to 90:10 to 50. For example, YD-011 (epoxy equivalent: 500 g / eq) and YD-128 (epoxy equivalent: 190 g / eq) can be mixed at the above-mentioned weight ratio.

In the thermosetting resin composition for forming an insulating resin layer according to the present invention, the content of the epoxy resin may be in the range of 10 to 40 parts by weight, preferably 15 to 30 parts by weight per 10 to 60 parts by weight of the polyphenylene ether modified resin Can be negative. When the content of the epoxy resin falls within the above range, the curing property, the molding processability and the adhesive force of the resin composition are good.

(c)

The third component constituting the thermosetting resin composition for forming an insulating resin layer according to the present invention is a curing agent (c).

The curing agent may be a conventional curing agent known in the art without limitation, and may be appropriately selected depending on the type of epoxy resin to be used. Non-limiting examples of usable curing agents include phenol-based, anhydride-based, dicyanamide-based, and curing agents. Of these, phenolic curing agents are preferred because they can further improve heat resistance and adhesiveness.

Non-limiting examples of the phenolic curing agent include phenol novolak, cresol novolac, bisphenol A novolac, naphthalene type, etc. These may be used alone or in combination of two or more.

In the thermosetting resin composition for forming an insulating resin layer according to the present invention, the content of the curing agent can be appropriately controlled in accordance with the content of the epoxy resin. In order to maintain the surface roughness (Ra) of the insulating layer at a low level while further improving the heat resistance and the adhesive strength, it is preferable to mix the curing agent and the epoxy resin in a weight ratio of 20 to 50:80 to 50.

In the thermosetting resin composition for forming an insulating resin layer of the present invention, the content of the curing agent may be 10 to 40 parts by weight, preferably 10 to 30 parts by weight, relative to 10 to 60 parts by weight of the polyphenylene ether modified resin Lt; / RTI &gt; When the content of the curing agent falls within the above-mentioned range, the curing property, strength, heat resistance and fluidity of the resin composition are satisfactory.

In the present invention, the compounding ratio of the epoxy resin and the curing agent may be such that the phenolic hydroxyl group equivalent of the curing agent is in the range of 0.4 to 2.0, preferably 0.5 to 1.0, in terms of the epoxy equivalent of the epoxy resin . &Lt; / RTI &gt;

(d) Modified epoxy resin

The fourth component constituting the thermosetting resin composition for forming an insulating resin layer according to the present invention is a modified epoxy resin (d).

Examples of the usable modified epoxy resin include dimer acid-modified epoxy resin, urethane-modified epoxy resin, and carboxyl-terminated butadiene acrylonitrile (CTBN). These resins may be used alone or in combination of two or more can do.

The dimeric acid-modified epoxy resin is liable to form a cured product which gives flexibility by the structural factors of the dimeric acid-modified part when the insulating layer is formed by the curing reaction. Further, by providing elastomeric properties to the insulator, the plating adhesion, heat resistance, and humidity resistance characteristics can be improved.

Such a dimeric acid-modified epoxy resin is preferable because it has excellent plating adhesion properties and further improved heat resistance and moisture resistance when the modification ratio is about 5 to 30%. Examples of usable dimeric acid-modified epoxy resins include KSR-200 (Kukdo Chemical Co., Ltd.) and the like. The epoxy equivalent weight and viscosity of the dimeric acid-modified epoxy resin are not particularly limited, but when the epoxy equivalent is about 100 to 500 g / eq and the viscosity is about 5,000 to 30,000 cps, the plating adhesion, the heat resistance and the moisture resistance can be further improved desirable.

The urethane-modified epoxy is an insulating layer, which improves the plating adhesion and the ductility of the insulating layer when used, thereby improving heat resistance and moisture resistance.

Examples of the urethane-modified epoxy resin that can be used include UME-315 (Kukdo Chemical), UME-330 (Kukdo Chemical), and the like. These may be used alone or in combination of two or more. In addition, the urethane-modified epoxy resin is preferable because it has excellent plating adhesion properties and further improved heat resistance and moisture resistance when the modification ratio is about 5 to 30%. The epoxy equivalent weight and viscosity of the urethane-modified epoxy resin are not particularly limited. However, when the epoxy equivalent is about 100 to 500 g / eq and the viscosity is about 5,000 to 30,000 cps, the coating adhesion, heat resistance, .

BACKGROUND ART Carboxyl terminated butadiene rubber (CTBN) is a type of rubber-modified epoxy resin added to improve the compatibility of rubber and epoxy. The carboxyl-terminated butadiene rubber (CTBN) Can play a role.

In the thermosetting resin composition for forming an insulating resin layer according to the present invention, the content of the modified epoxy resin may be 5 to 40 parts by weight, preferably 5 to 30 parts by weight, based on 100 parts by weight of the mixture of the epoxy resin and the curing agent And more preferably in the range of 5 to 15 parts by weight. If the amount of the modified epoxy resin is less than 5 parts by weight, the coating property and the plating adhesion property may be deteriorated. If the amount exceeds 40 parts by weight, the compatibility between the modified epoxy resin and the epoxy resin is poor and coating property and adhesion between the printed circuit board and the insulator And a reduction in heat resistance is expected.

(e) Flame retardant

The thermosetting resin composition for forming an insulating resin layer according to the present invention may further contain a flame retardant (e) if necessary.

The flame retardant may be any conventional flame retardant known in the art, but it is preferably an organic phosphorus flame retardant, an organic nitrogen-containing phosphorus compound, a nitrogen compound, a silicon flame retardant, or a metal hydroxide.

The flame retardant may be contained in an amount of 5 to 40 parts by weight, preferably 5 to 30 parts by weight, more preferably 5 to 15 parts by weight, based on 10 to 60 parts by weight of the polyphenylene ether modified resin have. When the content is in the above range, the resin composition has sufficient flame resistance and the heat resistance of the cured product is also preferable.

The thermosetting resin composition for forming an insulating resin layer of the present invention may further comprise a curing accelerator. The curing accelerator may be an organic metal salt or an organic metal complex containing at least one metal selected from the group consisting of iron, copper, zinc, cobalt, lead, nickel, manganese and tin.

Examples of the organic metal salt or organometallic complex include iron naphthenate, copper naphthenate, zinc naphthenate, cobalt naphthenate, nickel naphthenate, manganese naphthenate, tin naphthenate, zinc Octanoate, tin octanoate, iron octanoate, copper octanoate, zinc 2-ethylhexanate, lead acetylacetonate, cobalt acetylacetonate, or dibutyltin maleate. But is not limited thereto. These may be used singly or in combination of two or more. The curing accelerator may be included in an amount of 0.01 to 1 part by weight based on 10 to 60 parts by weight of polyphenylene ether, but is not limited thereto.

In addition to the above-mentioned components, the thermosetting resin composition for forming an insulating resin layer of the present invention may further contain additives such as inorganic fillers. Examples of the inorganic filler include, but are not limited to, silica, alumina, aluminum hydroxide, calcium carbonate, clay, talc, silicon nitride, boron nitride, titanium oxide, barium titanate or titanate.

On the other hand, the resin composition of the present invention may contain various additives such as flame retardants generally known in the art, other thermosetting resins, thermoplastic resins and oligomers thereof, Other additives such as a polymer, a solid rubber particle or an ultraviolet absorber, an antioxidant, a polymerization initiator, a dye, a pigment, a dispersing agent, a thickener, a leveling agent and the like. For example, flame retardants such as organic phosphorus flame retardants, organic nitrogen-containing phosphorus compounds, nitrogen compounds, silicone flame retardants and metal hydroxides; Organic fillers such as silicone-based powder, nylon powder, and fluororesin powder; thickeners such as orthobenzene and benzene; Polymer-based defoaming agents or leveling agents such as silicones and fluororesins; Adhesion-imparting agents such as imidazole-based, thiazole-based, triazole-based and silane-based coupling agents; Phthalocyanine, carbon black, and other coloring agents.

The thermosetting resin composition may be blended with a thermoplastic resin for the purpose of imparting appropriate flexibility to the cured resin composition. Examples of such a thermoplastic resin include phenoxy resin, polyvinyl acetal resin, polyimide, polyamideimide, polyethersulfone, polysulfone and the like. Any one of these thermoplastic resins may be used alone, or two or more of them may be used in combination.

Considering the physical stiffness, thermal expansion coefficient, thinning, etc. of the insulating resin sheet 100 according to the present invention, the thickness of the insulating resin layer 120 may be in the range of 1 to 50 탆 which does not affect the thermal expansion characteristics of the substrate, Preferably in the range of 1 to 30 mu m.

It is preferable that the insulating resin layer 120 is protected by a protective film in order to prevent damage to the surface and adhesion of foreign matter. The protective film may be the same as a conventional plastic film known in the art. The thickness of the protective film may range from 1 to 40 mu m, preferably from 10 to 30 mu m. Further, it is possible to apply a film which can be peeled after heating, pressing, and pressing under coating.

According to an example of the present invention, the insulating resin sheet 100 may further include a support layer 140 on the insulating resin layer 120.

As the support, a plastic film may be used, and a metal foil such as a release film, a copper foil, and an aluminum foil may be used as a support. Examples of usable plastic films include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate; Polycarbonate, acrylic resin, cyclic polyolefin, triacetyl cellulose, polyether sulfide, polyether ketone, polyimide and the like.

When a polyimide (PI) film is used as the support, high-temperature pressing at about 220 ° C is possible. In the case of a polyethylene terephthalate (PET) film, a low-temperature press of about 180 占 폚 may be used. In this case, when a plastic film is used as the support, it is preferable to use a support having a release layer, in which the surface to be cured of the cured layer of the thermosetting resin composition has been subjected to release treatment, in order to enable release from the cured product of the thermosetting resin composition. In this case, the plastic film may be a matte-treated or corona-treated film, and a release layer may be formed on the treated surface.

Further, since the metal foil can be removed by etching, it is not necessary to further use the release layer when the metal foil is used as a support. It is also possible to use the metal foil as a conductor layer without peeling off. Examples of usable metal foils include aluminum foil and copper foil. When such a metal foil is used as a support layer, a high-temperature press of about 220 캜 is possible.

The thickness of the support layer 140 is not particularly limited, but may be in the range of 10 to 150 占 퐉, and preferably in the range of 25 to 50 占 퐉.

According to another embodiment of the present invention, the insulating resin sheet 100 may further include a release layer 130 between the insulating resin layer 120 and the support layer 140.

The releasing layer 130 has a function of easily separating the insulating resin layer 120 so that the insulating resin layer 120 can maintain its shape without deteriorating when the supporting layer 140 is separated from the cured product of the thermosetting resin composition after pressing. Here, the release layer may be a commonly used film-type release material.

The releasing agent used in the releasing layer 130 is not particularly limited to its component as long as the insulating resin layer can be peeled completely from the support, and conventional releasing agent components known in the art can be used. Non-limiting examples thereof include epoxy-based releasing agents, releasing agents comprising fluororesins, silicone-based releasing agents, alkyd resin-based releasing agents, and water-soluble polymers. The thickness of the release layer 130 is not particularly limited. For example, the thickness of the release layer 130 may be in the range of 0.01 to 10 mu m, preferably in the range of 0.1 to 5 mu m.

The method for forming the release layer 130 is not particularly limited, and known methods such as hot press, thermal roll laminate, extrusion laminate, application of coating liquid, and drying can be employed.

In a preferred example according to the present invention, the total thickness of the insulating resin sheet may range from 7 to 200 mu m.

<Manufacturing Method of Insulating Resin Sheet>

The insulating resin sheet 100 for forming a flexible printed circuit board according to the present invention can be largely manufactured by the following two methods. However, it is not particularly limited.

For example, the insulating resin layer 120 of the insulating resin sheet can be obtained by applying a thermosetting resin composition varnish for forming an insulating resin layer on the surface of a polyimide, and simultaneously performing heating, drying, and curing, or The adhesive sheet or film obtained by heating and drying the resin varnish applied on the support may be placed on the surface of the polyimide film and then adhered.

(I) coating a thermosetting resin composition for forming an insulating resin layer on a first surface of a polyimide film and drying the coated thermosetting resin composition; (Ii) coating and drying the thermosetting resin composition on the second side of the polyimide film; And (iii) drying the double-side-coated polyimide film and curing the composition.

When a resin composition for forming an insulating resin layer is applied on a polyimide film substrate, a roll coater, a bar coater, a coater, a blade coater, a lip coater, a rod coater, a squeeze coater, a reverse coater, a transfer roll coater, A thermo-curable resin composition may be coated on a substrate by a coater, a spray coater, or the like, followed by drying at a temperature of 50 to 130 ° C for 1 to 30 minutes.

Examples of the organic solvent usable in preparing the resin composition for forming the insulating resin layer include ketones such as acetone, methyl ethyl ketone and cyclohexanone, ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate , And carbitol acetate; carbohydrates such as cellosolve and butyl carbitol; aromatic hydrocarbons such as toluene and xylene; dimethylformamide; dimethylacetamide; and N-methylpyrrolidone. The organic solvents may be used alone or in combination of two or more.

In the first method described above, an insulating resin sheet can be manufactured through a total of three drying processes without using a heating / press-pressing step.

Meanwhile, in a second embodiment of the production method according to the present invention, there is provided a method for producing a thermosetting resin composition, comprising the steps of: (i) providing a first adhesive sheet coated with a thermosetting resin composition for forming an insulating resin layer on a first surface of a first support, Preparing a second adhesive sheet on which the thermosetting resin composition is applied; And (ii) a first adhesive sheet and a second adhesive sheet are laminated on the upper and lower surfaces of the polyimide film, respectively, wherein the composition layer for forming the insulating resin layer is disposed so as to be in contact with the polyimide film, &Lt; / RTI &gt; to cure the composition.

Here, it is preferable that the step (ii) is complete curing of the composition through a roll lamination or press process. The conditions such as roll lamination and pressing process are not particularly limited and can be suitably adjusted under ordinary conditions known in the art.

The first support and the second support are each treated with a releasing agent, and a release layer is preferably disposed between the support and the composition for forming an insulating resin layer.

In the second method, an insulating resin layer capable of realizing a microcircuit is coated on a carrier substrate treated with a release agent, and then the coated substrate and the polyimide film are completely cured through a heating / pressing process such as roll lamination or press.

In the second method, the insulating resin sheet 1000 can be obtained by bonding the cured insulating resin layer 120 and the polyimide film 110 to each other. For example, the support layer 140 and the thermosetting resin A method of laminating the insulating resin layer 120 composed of the coating layer of the composition on one side of the polyimide film 110 and adhering the laminated film to the insulating resin layer 120 and bonding the polyimide film 110 to the insulating resin layer 120 The sheet-like insulating resin layer 120 and the polyimide film 110 may be rolled up in a roll form and laminated continuously. Alternatively, both the roll-type sheets may be cut and then laminated .

<Flexible Copper Clad Laminate (FCCL)>

The present invention provides a flexible copper-clad laminate using the above-described insulating resin sheet.

The flexible copper-clad laminate refers to a laminate in which a polyimide film and a copper foil are bonded as a material of a flexible printed circuit board (FPCB). The flexible copper-clad laminates use an insulating resin sheet according to the present invention in which a flexible polyimide film and an insulating resin layer capable of forming an illuminance by a desmearing process are sequentially laminated, thereby reducing the total lamination thickness, A high-density fine circuit pattern can be realized while increasing the degree of design freedom.

According to a preferred embodiment of the present invention, the flexible copper-clad laminate (FCCL) comprises an insulating resin sheet; And a copper foil layer formed on upper and lower surfaces of the insulating resin layer of the insulating resin sheet, respectively.

In this case, the copper foil layer may include any copper foil known in the art without limitation, and includes all the copper foils manufactured by the rolling method and the electrolytic method. For example, an electrolytic plating layer, an electroless plating layer, or a sputtering method.

The copper foil layer may have a predetermined surface roughness (Rz), and the surface roughness is not particularly limited. For example, the surface roughness may range from 0.6 mu m to 3.0 mu m.

The thickness of the copper foil layer is not particularly limited, and may be less than 3 占 퐉 in consideration of the thickness and the mechanical properties of the final product. A predetermined pattern may already be formed on the copper foil layer.

&Lt; Printed circuit board and manufacturing method thereof >

The present invention provides a printed circuit board, preferably a flexible printed circuit board (FPCB), which is manufactured using an insulating sheet.

The printed circuit board in the present invention refers to a printed circuit board laminated in a single layer or two to three or more layers by a plating through hole method, a build-up method, or the like. Since the flexible printed circuit board of the present invention is a non-adhesive type that does not include an adhesive, it can be thin and long-lasting. In addition, it is possible to form a fine circuit pattern by easy formation of roughness and subsequent plating by a semi-additive method, and it is also possible to minimize the defects of the pattern side generated in the electroplating process, (See Figs. 4 and 6 below). In addition, a high-density microcircuit pattern can be realized while reducing the total stacking thickness and increasing the degree of design freedom of the final product.

According to a preferred embodiment of the present invention, the printed circuit board includes an insulating resin sheet; A copper foil plating layer formed on the upper and lower surfaces of the insulating resin layer of the insulating resin sheet and having a predetermined pattern; And a plurality of through holes formed to penetrate the insulating resin sheet and plated to electrically connect the patterns of the copper foil layer formed on the upper and lower surfaces, respectively.

Here, the line / space (L / S) of the copper-plated layer circuit pattern may be in the range of 2 탆 / 2 탆 to 30 탆 / 30 탆, but is not particularly limited thereto.

The printed circuit board according to the present invention can be manufactured by a conventional method known in the art, for example, semi-additive, except that the above-described insulating resin sheet is used.

In one preferred embodiment of the above production method, (i) forming at least one hole in the above-described insulating resin sheet; (Ii) desmearing the surface and the inside of the film to form roughness; (Iii) forming an electroless plating layer on the rough surface and the hole inner surface of the film; (Iv) forming a pattern on the formed electroless plating layer using a photoresist; (v) forming a circuit layer by electrolytic plating on the pattern; And (vi) peeling the photoresist and removing the exposed electroless plating layer.

Hereinafter, a manufacturing process of a printed circuit board according to an embodiment of the present invention will be described in detail with reference to FIG. However, the present invention is not limited to the processes illustrated below.

1) One or more holes are formed in the insulating resin sheet (see Fig. 3 (a)

A laser is irradiated on the insulating resin sheet to form a hole. The laser may be an excimer laser, a UV laser, a carbon dioxide gas (CO ₂ ) laser, or the like.

When this step is performed, a hole penetrating the entire insulating resin sheet is formed.

2) The surface of the insulating resin sheet and the inner surface of the hole are subjected to desmear treatment to form roughness (see FIG. 2 (b)).

The desmear process is a process for removing resin residues (smear) after laser irradiation with an oxidizing agent such as permanganate salt, dichromate, or the like. In this step, the surface of the insulating resin sheet and the inner surface of the hole are processed And a rough surface having an appropriate roughness (roughness) is formed.

At this time, if the desmear treatment is insufficient and the desmear resistance is not sufficiently secured, even if the metal plating treatment is performed on the hole, the conductivity of the upper layer metal wiring and the lower layer metal wiring can not be sufficiently secured due to the smear. Further, the surface of the smooth insulating resin sheet can be roughened at the same time, and the adhesion of the conductive wiring circuit formed by the subsequent metal plating can be increased.

If necessary, an etching process may be further carried out after the desmearing step to maintain a horizontal roughness surface having an appropriate roughness on the insulating resin sheet.

It is preferable that the surface of the insulating resin sheet after the desmearing step has a desired roughness for forming a fine circuit pattern. For example, the surface roughness of the insulating resin sheet after the desmearing step may be in the range of 50 nm to 1,000 nm, and preferably in the range of 100 nm to 500 nm.

3) An electroless plating layer is formed on the rough surface and the inner surface of the hole of the insulating resin sheet (see Fig. 3 (c)).

Electroless plating is performed on the rough surface and the inner surface of the hole to form a comparatively thin plating layer. This electroless plating layer secures adhesion strength to the insulating resin layer in advance in order to raise the fine circuit pattern layer to be formed thereon.

Generally, the adhesiveness between the formed circuit electrode and the substrate is closely related, and an electroless plating layer is formed between the substrate and the circuit electrode. Here, since the electroless plating layer is formed using the surface-coated catalyst as an active point, ultimately, there is no adhesion with the substrate. Therefore, when the surface roughness of the substrate is large, the adhesion between them is kept good by the anchor effect, but if there is no roughness on the surface of the substrate, the adhesiveness tends to be low. Therefore, it is preferable to adjust the surface roughness to 0.1 times or less of the formed circuit width because a good circuit shape can be obtained.

At this time, the electroless plating layer to be a seed layer of the electroplating layer is preferably in the range of 0.1 to 5 mu m.

4) A pattern is formed on the electroless plating layer formed using a photoresist (see Fig. 3 (c)).

In order to form a desired circuit pattern on the electroless plating layer, a fine circuit pattern is formed through a process of coating a photoresist as a lithography process and forming an opening for forming an outer layer pattern.

Here, the photoresist may be a dry film or the like.

5) A circuit layer formed by electrolytic plating is formed on the pattern (see Fig. 3 (d)).

Thereafter, a conductor layer for forming the fine circuit pattern is formed on the opening of the photoresist layer by electrolytic plating.

Through this step, the electroplated layer forms a new circuit layer connected to the plated copper layer by the holes. Here, the thickness of the electroplating layer is preferably in the range of about 1 m to 100 m.

The line / space of the circuit pattern formed in this step may be less than 30 탆 / 30 탆, preferably in the range of 2 탆 / 2 탆 to 30 탆 / 30 탆, more preferably 2 탆 / 2 탆 to 20 탆 / 20 Lt; / RTI &gt;

6) The photoresist is peeled off and the exposed electroless plating layer is removed.

Finally, the unnecessary photoresist layer is removed and the exposed electroless plating layer is removed to complete the circuit pattern.

Then, if necessary, the manufacturing is completed by further performing a manufacturing process of a conventional printed circuit board known in the art, for example, an electronic element mounting process.

The above-described method of manufacturing a printed circuit board can be performed by modifying the steps of the respective processes or selectively mixing them according to design specifications, not by sequentially performing the steps described above.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, the following Examples and Experimental Examples are merely illustrative of the present invention, and the scope of the present invention is not limited by the following Examples and Experimental Examples.

[Examples 1 to 4]

1. Preparation of Resin Composition

A resin composition for forming an insulating resin layer was prepared by mixing the polyphenylene ether modified resin, BCF, epoxy resin, curing agent, modified epoxy resin and, if necessary, flame retardant in accordance with the composition shown in Table 1 below. In Table 1, the unit of usage of each composition is parts by weight.

2. Manufacture of insulating resin sheet and flexible printed circuit board

For evaluation of the present invention, an APICAL polyimide film (12.5 占 퐉) 12.5NPI manufactured by Kaneka Co., Ltd. was coated on one side with an adhesive layer of 20 占 퐉 for adhesion to an inner wiring board and dried to form a B-stage form. Thereafter, the resin composition was coated on the other surface of the PI film to a thickness of 5 μm using a Gravure Coater, and then a coating layer was formed on the other surface of the PI film. And dried for 5 to 10 minutes.

The insulating resin sheet prepared above was subjected to hole processing, desmear treatment, electroless plating layer formation, and circuit formation according to a conventional method to produce a flexible printed circuit board (FPCB).

 [Comparative Examples 1 and 2]

A resin composition, an insulating resin sheet and a printed circuit board were prepared in the same manner as in the above example, except that the composition shown in the following Table 1 was used. In Table 1, the unit of usage of each composition is parts by weight.

[ Comparative Example  3]

A printed circuit board was produced in the same manner as in the above example, except that polyimide for general FCCL was used.

[ Example  5 ~ 7]

A resin composition, an insulating resin sheet and a printed circuit board were prepared in the same manner as in the above examples, except that the compositions shown in Table 2 were used. In Table 2, the unit of usage of each composition is parts by weight.

[Comparative Examples 4 to 5]

A resin composition, an insulating resin sheet and a printed circuit board were prepared in the same manner as in the above examples, except that the compositions shown in Table 2 were used. In Table 2, the unit of usage of each composition is parts by weight.

Company

1) Epoxy resin 1: YD-011 (epoxy equivalent weight: 500 g / eq)

2) Epoxy resin 2: YD-128 (epoxy equivalent 190 g / eq)

3) Radical initiator: PB-I

4) Catalyst: Cobalt naphthanate

5) Hardener: KTG-105 (OH equivalent: 104 g / eq)

6) Modified Epoxy Resin 1: Dimeric acid-modified epoxy resin (KSR-200)

7) Modified Epoxy Resin 2: Urethane Modified Epoxy Resin (UME-315)

8) Modified Epoxy Resin 3: CTBN Modified Epoxy Resin (KR-207)

9) Flame retardant: phosphorus flame retardant (SPB-100)

Experimental Example 1. Evaluation of Surface Properties of Insulating Resin Sheet

The insulating resin sheets prepared in Example 1, Example 5, Comparative Example 1, and Comparative Example 4 were evaluated for their surface physical properties.

Each insulating resin sheet was subjected to desmear treatment, and then a scanning electron microscopic photograph was observed to evaluate their surface roughness and shape.

As a result of experiments, it was found that, in Example 1 and Example 5 in which BCF and HCA-HQ were applied to the insulating resin layer components, a regular shape was formed with dense surface roughness after the desmear treatment (see FIGS. 4 and 6) . As a result, the specific surface area of the roughness is increased and a good plating adhesion is obtained.

On the other hand, Comparative Example 1 and Comparative Example 4 in which conventional BPA was applied as an insulating resin layer component were irregularly formed with a large surface roughness after the desizing treatment (see FIGS. 5 and 7) Respectively. In addition, in the case of Comparative Example 3 in which the conventional general FCCL polyimide film was applied, plating was impossible at all.

Experimental Example 2. Evaluation of Physical Properties of Printed Circuit Board

The following tests were conducted on the flexible printed circuit boards prepared in Examples 1 to 7 and Comparative Examples 1 to 5, and the results are shown in Table 1 above.

1) Flexibility (Flexibility): The copper foil of the produced laminate was removed by etching, and the obtained insulation layer was folded and bent, and the flexibility was evaluated by the presence or absence of breakage at that time. (A: no break, B: fine break phenomenon, C: break)

2) Plating adhesion strength: The adhesion strength between the plated layer and the insulator was measured according to the test standard of IPC-TM-650 2.4.8.

3) Surface roughness: Ra value was measured using a non-contact 3D Optical Profiler (Bruker Contour GT) to measure the surface roughness. The Ra value is an average value of the height calculated over the entire measurement area, and specifically, the absolute value of the height varying in the measurement area is measured from the average line surface and arithmetically averaged. Here, the average roughness It is the value measured according to the obtained.

4) Lead heat resistance: The sample was cut into a size of 5 cm x 5 cm in a 288 ° C water bath, and the time at which the abnormality began to occur was measured.

5) Flame retardancy: Proceed according to UL 94 VTM test standard.

  V-0: Within 10 seconds per specimen / 5 sets in total, within 50 seconds

  V-1: Within 30 seconds per specimen / 10 times total, within 250 seconds

As a result of the test, the printed circuit board using the insulating resin sheet of the present invention had a surface roughness of less than half that of the conventional product after the dismear treatment and exhibited excellent characteristics in terms of flammability, plating adhesion, flexural strength and heat resistance (See Tables 1 and 2).

Accordingly, a multilayer printed circuit board with high reliability can be manufactured in the future, and it is considered to be usefully used as a constituent material of a small and lightweight new semiconductor package.

Claims (24)

Polyimide films; And
An insulating resin layer formed on the upper and lower surfaces of the polyimide film, respectively,
And an insulating resin sheet for forming a flexible printed circuit board (FPCB)
The insulating resin layer
(a) polyphenylene ether is reacted with 9,9-bis (hydroxyaryl) fluorene (BCF) or 9,10-dihydro-9-oxa-10- (dihydroxyaryl) -10-phosphaphenanthrene A polyphenylene ether modified resin obtained by redistribution in the presence of 10-oxide (HCA-HQ);
(b) an epoxy resin;
(c) a curing agent; And
(d) at least one modified epoxy resin selected from the group consisting of a dimer acid-modified epoxy resin, a urethane-modified epoxy resin, and a carboxyl-terminated butadiene acrylonitrile (CTBN) Features an insulating resin sheet. delete The thermosetting resin composition according to claim 1, wherein the thermosetting resin composition comprises a polyphenylene ether modified resin (a) in which polyphenylene ether has been redistributed and reacted in the presence of 9,9-bis (hydroxyaryl) fluorene (BCF) (e) a flame retardant. The polyphenylene ether-modified resin (a) according to claim 1, wherein the polyphenylene ether-modified resin (a) has a molecular weight lower than that of the high molecular weight polyphenylene ether resin through a redistribution reaction in a high molecular weight polyphenylene ether resin having a number average molecular weight of 10,000 to 30,000 Wherein the number average molecular weight is in the range of 1,000 to 15,000. The insulating resin sheet according to claim 1, wherein the epoxy resin (b) is a mixture of two or more epoxy resins different in epoxy equivalent. The epoxy resin composition according to claim 1, wherein the epoxy resin (b) is a first epoxy resin having an epoxy equivalent of 400 to 1,000 g / eq; And a second epoxy resin having an epoxy equivalent of 100 to 300 g / eq at a weight ratio of 50 to 90:10 to 50. The insulating resin sheet according to claim 1, wherein the curing agent (c) is selected from the group consisting of phenol-based, anhydride-based, and dicyanamide-based curing agents. The insulating resin sheet according to claim 1, wherein the modified epoxy resin (d) has an epoxy equivalent of 100 to 500 g / eq and a viscosity of 5000 to 30,000 cps. The insulating resin sheet according to claim 3, wherein the flame retardant (e) is at least one member selected from the group consisting of organic phosphorus flame retardants, organic nitrogen-containing phosphorus compounds, nitrogen compounds, silicon flame retardants, and metal hydroxides. The thermosetting resin composition according to claim 3, wherein the thermosetting resin composition comprises
(a) 10 to 60 parts by weight of a polyphenylene ether modified resin;
(b) 10 to 40 parts by weight of an epoxy resin;
(c) 10 to 40 parts by weight of a curing agent; And
(d) 5 to 40 parts by weight of a modified epoxy resin,
When the polyphenylene ether-modified resin (a) is a polyphenylene ether which has undergone redistribution reaction in the presence of 9,9-bis (hydroxyaryl) fluorene (BCF), the polyphenylene ether- Further comprising a flame retardant (e) in a range of 5 to 40 parts by weight relative to the total weight of the insulating resin sheet. The film according to claim 1, wherein the thickness of the polyimide film is in the range of 5 탆 to 100 탆,
Wherein the thickness of the insulating resin layer formed on each of the upper and lower surfaces of the polyimide film is in the range of 1 占 퐉 to 50 占 퐉. The method of claim 1, wherein the total thickness is less than 7 Lt; RTI ID = 0.0 &gt; um. &Lt; / RTI &gt; The insulating resin sheet according to claim 1, further comprising a support layer on the insulating resin layer. The insulating resin sheet according to claim 13, further comprising a release layer between the insulating resin layer and the support layer. 14. The insulating resin sheet according to claim 13, wherein the support layer is a plastic film or a metal foil. An insulating resin sheet according to any one of claims 1 to 15, And
A copper foil layer formed on the upper and lower surfaces of the insulating resin layer of the insulating resin sheet,
(FCCL). An insulating resin sheet according to any one of claims 1 to 15,
A copper foil plating layer formed on the upper and lower surfaces of the insulating resin layer of the insulating resin sheet and having a predetermined pattern; And
A plurality of through holes (not shown) are formed through the insulating resin sheet to electrically connect patterns of the copper foil layer formed on the upper and lower surfaces,
And a printed circuit board. The printed circuit board according to claim 17, wherein the line / space (L / S) of the copper-plated layer pattern is in the range of 2 탆 / 2 탆 to 30 탆 / 30 탆. (i) coating a thermosetting resin composition for forming an insulating resin layer on a first side of a polyimide film, followed by drying;
(Ii) coating and drying the thermosetting resin composition on the second side of the polyimide film; And
(Iii) drying the double-side-coated polyimide film and curing the composition,
The thermosetting resin composition for forming the insulating resin layer
(a) polyphenylene ether is reacted with 9,9-bis (hydroxyaryl) fluorene (BCF) or 9,10-dihydro-9-oxa-10- (dihydroxyaryl) -10-phosphaphenanthrene A polyphenylene ether modified resin obtained by redistribution in the presence of 10-oxide (HCA-HQ);
(b) an epoxy resin;
(c) a curing agent; And
(d) at least one modified epoxy resin selected from the group consisting of a dimer acid-modified epoxy resin, a urethane-modified epoxy resin, and a carboxyl-terminated butadiene acrylonitrile (CTBN). A method for producing an insulating resin sheet for forming a flexible printed circuit board. (i) a first adhesive sheet coated with a thermosetting resin composition forming an insulating resin layer on a first surface of a first support, a second adhesive sheet coated with the thermosetting resin composition on a first surface of a second support, Respectively; And
(Ii) a first adhesive sheet and a second adhesive sheet are laminated on the upper and lower surfaces of the polyimide film, respectively, and the composition layer for forming the insulating resin layer is arranged so as to be in contact with the polyimide film, And curing the composition,
The thermosetting resin composition for forming the insulating resin layer
(a) polyphenylene ether is reacted with 9,9-bis (hydroxyaryl) fluorene (BCF) or 9,10-dihydro-9-oxa-10- (dihydroxyaryl) -10-phosphaphenanthrene A polyphenylene ether modified resin obtained by redistribution in the presence of 10-oxide (HCA-HQ);
(b) an epoxy resin;
(c) a curing agent; And
(d) at least one modified epoxy resin selected from the group consisting of a dimer acid-modified epoxy resin, a urethane-modified epoxy resin, and a carboxyl-terminated butadiene acrylonitrile (CTBN). A method for producing an insulating resin sheet for forming a flexible printed circuit board. The method according to claim 20, wherein the step (ii) comprises curing the composition by a roll lamination or a pressing process. 21. The flexible printed circuit board according to claim 20, wherein the first support and the second support are respectively treated with a releasing agent, and a release layer is disposed between the support and the composition for forming an insulating resin layer. &Lt; / RTI &gt; (i) forming at least one hole in the insulating resin sheet according to any one of claims 1 to 15;
(Ii) desmearing the surface and the inside of the film to form roughness;
(Iii) forming an electroless plating layer on the rough surface and the hole inner surface of the film;
(Iv) forming a pattern on the formed electroless plating layer using a photoresist;
(v) forming a circuit layer by electrolytic plating on the pattern; And
(Vi) peeling the photoresist and removing the exposed electroless plating layer
And a step of forming the printed circuit board. 24. The method of claim 23, wherein, if the insulating resin sheet comprises a release layer, a support layer or both, removing the release layer, the support layer, or all of them between step (i) and step (ii) Wherein the method comprises the steps of:

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