KR20150077225A - 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 an insulating resin sheet for forming a flexible printed circuit board (FPCB) including a polyimide film; a low dielectric constant polyphenylene ether (PPE) resin insulation layer formed on one side or both sides of the polyimide film; and a thermoplastic polyimide layer formed on the polyphenylene ether (PPE) resin insulation layer, and forming a certain surficial roughness on the surface, to a manufacturing method thereof, and to a flexible printed circuit board including the insulating resin sheet. Provided in the present invention are an insulating resin sheet achieving excellent additive, low dielectric constant, and a fine circuit pattern, and a buildup printed circuit board using the same.

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 an insulating layer of a build-up printed circuit board capable of simultaneously realizing a high-density fine circuit pattern implementation, good adhesiveness and low dielectric constant characteristics, a method for producing the same, To a flexible printed circuit board and a method of manufacturing the same.

BACKGROUND ART [0002] Recently, electronic products such as mobile phones and tablet PCs have rapidly advanced in performance, speed, and densification, and thinning and densification of FPCB substrates are accelerating. In order to cope with such technology trends, a micro-circuit pattern embodying technique and appropriate plating reliability and low light-emitting material are required.

Examples of materials for implementing the conventional microcircuits include sputtering methods and films produced by a chemical etching method. The sputtering method is a method in which a metal thin film is deposited on a polyimide film which has not been treated (or treated by dry plasma treatment) through a sputtering process, and a metal thin film is formed on the metal thin film formed through the above process by a semi-additive process This is a method of implementing a microcircuit by plating. In this case, only the intermolecular force acts between the resin material constituting the substrate and the metal thin film layer, so that the initial adhesion can be ensured, but the adhesion, which is the core of this technology, is lowered due to thermal shock and chemical resistance.

Another method, chemical etching, is to form a thin metal film by electroless copper plating by forming the surface roughness through selective etching of the smearing material in the insulating layer resin material. The metal thin film formed through the above process is patterned through a semi-permanent process to realize a microcircuit. In this case, there is an advantage that the surface roughness of the film can be freely adjusted by selective etching, but the chemical resistance of the polyimide is low, and the chemical resistance of the resin material, which is an insulating layer, is weakened when the roughness is formed. The interlayer adhesive force between the substrates is not only low but also unsatisfactory in terms of moisture absorption and heat resistance.

SUMMARY OF THE INVENTION The present invention has been conceived in order to solve the above problems of the conventional micro-circuit method, and it is an object of the present invention to provide a polyimide film having a low dielectric constant polyphenylene ether (PPE) resin insulating layer and a thermoplastic polyimide layer sequentially formed thereon, A certain degree of roughness is formed on the surface of the polyimide to realize a technique of implementing a fine circuit pattern and a high adhesive force at the same time.

Accordingly, it is an object of the present invention to provide an insulating resin sheet of a new laminated structure capable of simultaneously realizing a fine circuit pattern implementation, good adhesiveness and low dielectric constant characteristics while solving the problems of the conventional microcircuit construction method.

The present invention also provides a flexible printed circuit board capable of reducing defects during circuit formation and exhibiting an interlaminar bond strength, a low dielectric constant and an improvement in long-term reliability at the same time by including an insulating layer formed using the insulating resin sheet, The present invention provides another object.

The present invention relates to a polyimide film; A polyphenylene ether (PPE) resin insulating layer formed on one or both surfaces of the polyimide film; And a thermoplastic polyimide layer formed on the polyphenylene ether (PPE) resin insulating layer and having a predetermined surface roughness formed on the surface thereof. The present invention also provides an insulating resin sheet for forming a flexible printed circuit board (FPCB).

According to a preferred embodiment of the present invention, the polyphenylene ether (PPE) resin insulating layer comprises (a) polyphenylene ether in combination with 9,9-bis (hydroxyaryl) fluorene (BCF) A polyphenylene ether modified resin obtained by a redistribution reaction in the presence of hydro-9-oxa-10- (dihydroxyaryl) -10-phosphapenanthrene 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) .

According to another preferred embodiment of the present invention, the surface roughness (Ra) of the thermoplastic polyimide layer is preferably in the range of 0.2 to 3.0 탆, and the thermoplastic polyimide layer is formed of polyimide, polyamide, polyamideimide, A resin, and a resin, and then curing the resin composition.

Here, the thickness of the polyimide film ranges from 5 占 퐉 to 100 占 퐉, the thickness of the polyphenylene ether (PPE) resin insulating layer ranges from 1 占 퐉 to 50 占 퐉, the thickness of the thermoplastic polyimide layer ranges from 1 占 퐉 to 50 mu m.

 According to a preferred embodiment of the present invention, a support layer may be further included on the thermoplastic polyimide layer, and a release layer may further be formed between the thermoplastic polyimide layer and the support layer.

The present invention also relates to the above-mentioned insulating resin sheet; And a copper foil layer formed on upper and lower surfaces of the thermoplastic polyimide layer of the insulating resin sheet, respectively.

In addition, the present invention relates to the above-mentioned insulating resin sheet; A copper foil plating layer formed on the upper and lower surfaces of the thermoplastic polyimide layer of the insulating resin sheet and having a predetermined pattern; And a plurality of through-holes plated to electrically connect the patterns of the copper-plated layer formed on the upper and lower surfaces, respectively, through the insulating resin sheet.

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

According to a preferred embodiment of the present invention, the production method comprises the steps of (i) coating a thermosetting resin composition for forming a polyphenylene ether (PPE) resin insulating layer on one or both surfaces of a polyimide film, (PPE) resin insulating layer; (Ii) coating a composition for forming a thermoplastic polyimide layer on the polyphenylene ether (PPE) resin insulating layer and then drying to form a thermoplastic polyimide layer; And (iii) a step of laminating the polyimide film and a copper foil having a predetermined surface roughness, wherein the thermoplastic polyimide layer of the polyimide film and the surface roughness of the copper foil are in contact with each other, And a step of transferring the surface roughness of the copper foil.

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

According to a preferred embodiment of the present invention, the manufacturing method comprises: (I) forming at least one hole in the above-described insulating resin sheet; (II) dishing the surface and the inside of the insulating resin sheet to form an illuminance; (III) forming an electroless plating layer on the rough surface and the inner surface of the hole of the insulating resin sheet; (IV) forming a pattern using a photoresist on the electroless plating layer formed; (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, a polyimide film capable of imparting flexibility to a substrate, a polyphenylene ether (PPE) resin insulating layer having excellent adhesion to other substrates and having low dielectric constant characteristics, And a thermoplastic polyimide layer in which a predetermined roughness surface is formed on the surface are sequentially laminated. Thus, a more precise microcircuit can be realized, and high adhesion and low dielectric constant characteristics can be ensured.

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 to 3 are cross-sectional views showing the construction of an insulating resin sheet according to an embodiment of the present invention.
4 is a cross-sectional view illustrating a manufacturing process of an insulating resin sheet according to an embodiment of the present invention.
5 is a scanning electron microscope (SEM) photograph of a microcircuit pattern implemented by applying the insulating resin sheet manufactured in Example 1 by a semi-additive method.
Description of the Related Art
10: polyimide film
20: polyphenylene ether (PPE) resin insulating layer
30: thermoplastic polyimide layer
40: release film

Hereinafter, the present invention will be described in detail.

The present invention provides a novel insulating resin sheet that exhibits 'excellent adhesion to a substrate and a plated layer' and 'low dielectric constant property' as a build-up material capable of forming an insulating layer in the production of a printed circuit board.

The insulating resin sheet comprises (A) a polyimide film; (B) a polyphenylene ether (PPE) resin insulating layer formed on one side or both sides of the polyimide film; And (C) a thermoplastic polyimide layer formed on the polyphenylene ether (PPE) resin insulating layer and having a predetermined surface roughness formed on the surface thereof, respectively (see FIGS. 1 to 2).

Here, the conventional polyphenylene ether (PPE) resin insulating layer is a resin insulating layer which is obtained by modifying a high molecular weight polyphenylene ether with a low molecular weight polyphenylene ether resin in the presence of a phenol derivative or a compound such as bisphenol A (BCA) or 9,10-dihydro-9-oxa-10- (dihydroxyaryl) -10-phosphaphenanthrene 10-oxide (HCA-HQ) , Solubility is improved, film coating is facilitated, molecular structure is blocked in rotation, and hydrophobic double ring hydrocarbon group is introduced in a large amount, thereby reducing electron polarization and lowering the dielectric constant. Particularly, since the molecular structure of BCF or HCA-HQ is bulky and higher in crystallinity than conventional phenol derivatives and bisphenol A, the improvement of the glass transition temperature (Tg) of the low molecular weight modified polyphenylene ether modified resin Can be achieved.

In the present invention, the thermoplastic polyimide layer is formed by the anchoring effect of the micro-roughness formed through the transfer of the matte surface of the copper foil and the intermolecular forces occurring at the interface, The bonding strength with the copper plating layer can be further improved. In addition, when the thermoplastic polyimide layer is located under the pattern layer, the content of impurities such as additives relative to a substrate using an epoxy resin as an insulating layer is low, so that the ion migration characteristic by the acceleration test is relatively low.

On the other hand, when solubilized polyimide is coated on a polyimide film, the interlayer adhesion between the already cured polyimide and the soluble polyimide resin is low, which causes a problem of lowering the plating adhesion of the entire insulating resin . Thus, in the present invention, by introducing a polyphenylene ether (PPE) resin insulating layer having high adhesion properties with polyimide, an insulating resin sheet having high adhesion and low dielectric properties can be provided.

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.

Referring to Figs. 1 and 2, the insulating resin sheet of the present invention comprises a polyimide film 10; A polyphenylene ether (PPE) resin insulating layer 20 formed on one side or both sides of the polyimide film; And a thermoplastic polyimide layer (30) formed on the polyphenylene ether (PPE) resin insulating layer and having a predetermined surface roughness formed on the surface thereof, each of which is sequentially stacked.

<Polyimide (PI) Film>

In the insulating resin sheet of the present invention, the polyimide film 10 not only serves as a base supporting film for physically supporting the insulating resin sheet, but also has 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.

<Polyphenylene ether (PPE) resin insulating layer>

In the insulating resin sheet of the present invention, the polyphenylene ether (PPE) resin insulating layer 20 is formed on one or both surfaces of the polyimide film 10, and the polyimide film, the thermoplastic polyimide layer, And a cured layer formed by curing a thermosetting resin composition capable of further improving the adhesive force with the copper foil layer and exhibiting low dielectric constant characteristics.

Preferable examples of the above-mentioned thermosetting composition for forming a polyphenylene ether (PPE) resin insulating layer include (a) polyphenylene ether in combination with 9,9-bis (hydroxyaryl) fluorene (BCF) A polyphenylene ether modified resin obtained by a redistribution reaction in the presence of dihydro-9-oxa-10- (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). 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 composition for forming the polyphenylene ether resin insulating layer according to the present invention is the 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 polyphenylene ether modified resin modified with a low molecular weight by redistribution reaction of polyphenylene ether is not particularly limited and conventional methods 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 composition for forming a polyphenylene ether resin insulating 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 relative to 100 parts by weight of the total resin composition, May range from 20 to 40. 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 composition for forming the polyphenylene ether resin insulating layer according to the present invention is the 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 with other substrates, 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 composition for forming a polyphenylene ether resin insulating layer according to the present invention, the content of the epoxy resin may be in the range of 10 to 40 parts by weight relative to 10 to 60 parts by weight of the polyphenylene ether modified resin, preferably 15 To 30 parts by weight. 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 composition for forming the polyphenylene ether resin insulating layer according to the present invention is the 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 composition for forming the polyphenylene ether resin insulating layer according to the present invention, the content of the curing agent may be appropriately controlled according to 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 composition for forming a polyphenylene ether resin insulating layer of the present invention, the content of the curing agent may be in the range of 10 to 40 parts by weight, preferably 10 to 40 parts by weight, relative to 10 to 60 parts by weight of the polyphenylene ether- 30 parts by weight. 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 composition for forming the polyphenylene ether resin insulating layer according to the present invention is the 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 composition for forming a polyphenylene ether resin insulating layer according to the present invention, the content of the modified epoxy resin may be in the range of 5 to 40 parts by weight, preferably 5 to 40 parts by weight based on 100 parts by weight of the mixture of the epoxy resin and the curing agent, 30 parts by weight, and more preferably 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 composition for forming the polyphenylene ether resin insulating layer according to the present invention may further contain a flame retardant (e) as required.

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 composition for forming the polyphenylene ether resin insulating 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 composition for forming the polyphenylene ether resin insulating 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.

The polyphenylene ether resin composition of the present invention may contain a flame retardant generally known in the art or other thermosetting resin or a thermoplastic resin not described above as long as the inherent characteristics of the resin composition are not impaired, Various additives such as various polymers such as an oligomer, solid rubber particles or ultraviolet absorbers, antioxidants, polymerization initiators, dyes, pigments, dispersants, thickeners, leveling agents 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 composition for forming the polyphenylene ether resin insulating layer may contain 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.

The polyphenylene ether (PPE) resin insulating layer 20 according to the present invention is formed by directly coating a thermosetting composition for forming a polyphenylene ether (PPE) resin insulating layer on one surface or both surfaces of a polyimide film 10 .

The thickness of the polyphenylene ether (PPE) resin insulating layer 20 formed with the above-described components is not particularly limited, and may be, for example, in the range of 1 to 50 μm, preferably in the range of 10 to 30 μm have.

Further, the polyphenylene ether (PPE) resin insulating layer 20 can exhibit excellent low dielectric constant characteristics. For example, the dielectric constant of the polyphenylene ether (PPE) resin insulating layer 20 may be 3.10 or less, preferably 2.6 to 3.06.

&Lt; Thermoplastic polyimide layer >

In the insulating resin sheet of the present invention, the thermoplastic polyimide layer 30 is formed on the surface or upper and lower surfaces of the polyphenylene ether (PPE) resin insulating layer 20, and a predetermined roughness surface is formed on the surface thereof , The adhesion with the copper foil plating layer formed thereafter is improved.

Wherein the thermoplastic polyimide (TPI) layer is formed by applying a resin composition for forming a thermoplastic polyimide layer, which comprises at least one resin selected from the group consisting of polyimide, polyamide, polyamideimide, and polyamic acid resin, . Or a soluble soluble polyimide (soluble PI) may be used.

At this time, the composition for forming a thermoplastic polyimide layer may be composed of a polyimide (PI) first resin and a surfactant, and may further include a second resin such as an epoxy resin, if necessary.

The polyimide (PI) is generally synthesized by condensation polymerization of an aromatic dianhydride and an aromatic diamine (or aromatic diisocyanate), and the polyimide is preferably a thermosetting polyimide. Non-limiting examples of usable polyimide resins include polyimide, polyamideimide, or a composite resin thereof.

Here, the polyimide resin may be prepared by imidizing a polyamic acid varnish obtained through imidization reaction of a diamine with a typical dianhydride known in the art.

In the resin composition for forming a thermoplastic polyimide layer according to the present invention, the content of the polyimide resin may range from 70 to 100 parts by weight, preferably from 80 to 100 parts by weight, relative to 100 parts by weight of the total resin composition have. When the content of the polyimide resin falls within the above-mentioned range, the curing property, the molding processability and the adhesive force of the resin composition are good.

In the resin composition for forming a thermoplastic polyimide layer of the present invention, the surfactant may be any conventional surfactant component known in the art without limitation.

The surfactant controls the surface tension of the thermoplastic polyimide layer-forming resin composition varnish, and is a component having an action to improve coatability, coatability and uniformity of the copper foil as a coating base material.

Nonlimiting examples of usable surfactants include fluorinated surfactants, silicone surfactants, nonionic surfactants, or a mixture of at least one of these surfactants.

In the resin composition for forming a thermoplastic polyimide layer according to the present invention, the content of the surfactant may be in the range of 0.001 to 0.1 parts by weight, preferably 0.001 to 0.05 parts by weight, based on 100 parts by weight of the total resin composition. When the content of the surfactant falls within the above-mentioned range, the coating property, coating property, and uniformity of the resin composition are good.

The resin composition for forming a thermoplastic polyimide layer according to the present invention may contain a second resin such as an epoxy resin if necessary.

The above-mentioned epoxy resin may be the same as or different from the component used in the above-mentioned composition for forming a polyphenylene ether (PPE) resin insulating layer.

In the resin composition for forming a thermoplastic polyimide layer according to the present invention, the content of the epoxy resin may be in the range of 0 to 30 parts by weight, preferably 0 to 20 parts by weight, based on 100 parts by weight of the total resin composition. 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.

In addition to the above-mentioned components, the resin composition for forming a thermoplastic polyimide layer of the present invention may further contain an additive such as an inorganic filler. As the inorganic filler that can be used, silica, alumina, aluminum hydroxide, calcium carbonate, clay, talc, silicon nitride, boron nitride, titanium oxide, barium titanate, or titanate may be used.

The thermoplastic polyimide layer-forming 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, 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.

The thermoplastic polyimide layer 30 according to the present invention is obtained by directly coating a composition for forming a thermoplastic polyimide layer on the surface of a polyphenylene ether (PPE) resin insulating layer 20 and drying the surface, To form a predetermined surface roughness surface.

At this time, the surface roughness Ra of the thermoplastic polyimide layer 30 may be in the range of 0.2 탆 to 3.0 탆. The transferring method is not particularly limited, and for example, the transferring may be performed by laminating a copper foil having a predetermined roughness surface on a surface thereof and a thermoplastic polyimide layer, followed by pressing.

The thickness of the thermoplastic polyimide layer 30 may be in the range of 1 to 50 占 퐉, preferably 10 to 30 占 퐉, in consideration of physical stiffness, heat-hygroscopicity, adhesion, thinning, etc. of the insulating resin sheet according to the present invention. Lt; / RTI &gt;

In the insulating resin sheet according to the present invention, the sum of the thicknesses of the polyphenylene ether (PPE) resin insulating layer 20 and the thermoplastic polyimide layer 30 may range from 1 to 30% of the total thickness, May range from 1 to 20%.

As shown in FIG. 3, the insulating resin sheet according to the present invention may further include a support layer 40 on the thermoplastic polyimide layer 30.

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.

In this case, when a plastic film is used as the support, it is preferable to further include a release layer treated with a release agent between the polyimide layer 30 and the support layer 40 in order to be easily peelable. The releasing agent used in the releasing layer is not particularly limited to its component, provided that the thermoplastic polyimide layer can be completely peeled off 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 plastic film may be a matte-treated or corona-treated film, and a release layer may be formed on the treated surface.

 The thickness of the support layer 40 is not particularly limited, but may be in the range of 10 to 150 mu m, preferably in the range of 25 to 50 mu m.

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, and preferably from 10 to 150 mu m.

<Manufacturing Method of Insulating Resin Sheet>

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

4 is a cross-sectional view illustrating a manufacturing process of an insulating resin sheet according to an embodiment of the present invention.

(I) a thermosetting composition for forming a polyphenylene ether (PPE) resin insulating layer is coated on one surface or both surfaces of a polyimide film, Followed by drying to form a polyphenylene ether (PPE) resin insulating layer; (Ii) coating a composition for forming a thermoplastic polyimide layer on the polyphenylene ether (PPE) resin insulating layer and then drying to form a thermoplastic polyimide layer; And (iii) a step of laminating the polyimide film and a copper foil having a predetermined surface roughness, wherein the thermoplastic polyimide layer of the polyimide film and the surface roughness of the copper foil are in contact with each other, And a step of transferring the surface roughness of the copper foil.

When the resin composition for forming a polyphenylene ether (PPE) resin insulating layer is applied on the polyimide film substrate in the step (i), for example, a roll coater, a bar coater, a comer coater, a blade coater, A thermosetting resin composition may be coated on a substrate by a coater, a squeeze coater, a reverse coater, a transfer roll coater, a gravure coater, a spray coater, etc., and dried at a temperature of 50 to 130 ° C for 1 to 30 minutes. Also in the case of applying the composition for forming a thermoplastic polyimide layer in the step (ii), the above-mentioned coating method may be used in the same manner.

When the resin composition for forming the PPE insulating layer is prepared, examples of usable organic solvents 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.

Here, the step (iii) may be performed by laminating the thermoplastic polyimide layer of the polyimide film and the surface roughness surface of the copper foil so as to be in contact with each other, followed by heating and pressing. At this time, it is preferable to completely cure the thermoplastic polyimide resin composition through a roll lamination or a press process.

In the present invention, conditions such as the roll lamination and the pressing process are not particularly limited and can be suitably adjusted under ordinary conditions known in the art.

<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 is a material of a flexible printed circuit board (FPCB), which refers to a laminate in which an insulating resin sheet and a copper foil are bonded. By using the insulating resin sheet according to the present invention, the flexible copper-clad laminate can realize high adhesion, excellent moisture absorption and heat resistance characteristics, and high-density fine circuit pattern while reducing the total lamination thickness and improving the degree of design freedom of the final product .

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 thermoplastic polyimide 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 (Ra). The surface roughness is not particularly limited. For example, the surface roughness may range from 0.2 탆 to 3.0 탆.

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. The flexible printed circuit board of the present invention can easily form a rough circuit by forming a roughness by a semi-additive method and then form a fine circuit pattern. In addition, The surface roughness is dense and the regular shape is formed, and it is possible to have excellent plating adhesion. 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 thermoplastic polyimide 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 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.

(I) forming at least one hole in the above-described insulating resin sheet; (II) dishing 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 using a photoresist on the electroless plating layer formed; (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. However, the present invention is not limited to the processes illustrated below.

1) At least one hole is formed in the insulating resin sheet.

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.

Conventionally, chemical etching is a chemical etching of an insulating layer with a strong basic solution. The roughness (Ra / Ra) value can be controlled by adjusting the concentration, etching time and temperature of the etching solution. However, when polyimide (PI) is used, the plating adhesion is lowered by chemical etching due to low chemical resistance of polyimide.

In contrast, the insulating resin sheet of the present invention has a surface roughness already formed on the outermost surface, so that a special chemical etching process is unnecessary. Even when a chemical etching process is performed, the chemical resistance of the insulating resin sheet is higher than that of polyimide As the thermoplastic polyimide layer (TPI) is present outside, deterioration of the plating adhesion due to chemical etching can be minimized.

On the other hand, the desmear process is a process for removing resin residues (smear) after laser irradiation by an oxidizing agent such as permanganate salt, dichromate, and the like. In this step, the surface of the insulating resin sheet and the inner surface of the hole 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 performed to maintain a horizontal roughness surface having an appropriate roughness on the insulating resin sheet after the desmear process.

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.

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 is intended to secure adhesion strength to the thermoplastic polyimide 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 formed electroless plating layer using a photoresist.

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.

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; Actually, it can be seen that the line space (L / S) of the circuit pattern formed in the present invention is 10 占 퐉 / 10 占 퐉 (see Fig. 5).

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]

1-1. Preparation of composition for forming polyphenylene ether (PPE) resin insulating layer

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.

1-2. Insulation resin sheet and flexible printed circuit board manufacturing

For the evaluation of the present invention, the polyphenylene ether resin insulating layer of Example 1-1 was coated by 3 to 4 占 퐉 on a Kapton polyimide film (38 占 퐉) 15FN019 manufactured by Dupont Co., And dried for about 10 minutes.

Then, a coating layer of UNIDIC-V800 thermoplastic polyimide composition, which is a soluble polyimide of soluble DIC, was formed on the formed polyphenylene ether resin insulating layer to a thickness of 4 μm and dried in a drier at 150 ° C. for 5 to 10 minutes Respectively. Thereafter, laminate was made using a copper foil having a rough surface formed on the thermoplastic polyimide layer produced, and then pressed to produce an insulating resin sheet.

The insulating resin sheet thus prepared was subjected to a hole forming process, a dismage process, an electroless plating layer formation process, and a circuit forming process according to a semi-additive process method to produce a flexible printed circuit board (FPCB) Respectively. The thickness of the formed plating layer was 12 占 퐉.

[Comparative Examples 1 and 2]

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

[Comparative Example 3]

A printed circuit board was fabricated in the same manner as in the above example, except that general purpose polyimide (PI) for general FCCL was used.

[Experimental Example 1] Evaluation of physical properties (1)

The following tests were conducted on the flexible printed circuit boards prepared in Examples 1 to 4 and Comparative Examples 1 to 3, respectively, and the results are shown in Table 1 below.

1) PI adhesion: 1 ~ 5 ㎛ epoxy resin was coated on unfaced polyimide film by using Slot Die coater (* micro coating machine capable of thin film coating). After drying at 150 ° C for about 2 minutes in a B-stage, 5 μm of thermosetting polyimide was coated on the surface of a 12 μm (1 / 3Oz) copper foil and laminated at 200 ° C. and evaluated for IPC-TM-650 2.4.8 A circuit pattern was formed on the laminate for a printed circuit board according to the standard. Then, the formed circuit pattern was pulled up in the direction of 90 DEG, and the time when the circuit pattern (copper layer) was peeled off was measured and evaluated.

2) Water absorption rate: Evaluated according to the evaluation standard of IPC-TM-650 2.6.2.1.

3) Moisture absorption and heat resistance: After leaving in a constant temperature and humidity chamber at 85 ° C and 85% for 24 hours, the laminate for printed circuit board was floated at solder 288 ° C according to IPC TM-650 2.4.13 evaluation standard, The time until the separation phenomenon occurred was measured and evaluated.

4) Permittivity: IPC-TM-650 Evaluation was carried out according to the evaluation standard of 2.5.5.3.

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)

As a result of the test, the insulating resin sheet of the present invention exhibited excellent properties in terms of adhesiveness to a polyimide (PI) film, water absorption, moisture absorption and heat resistance, and low dielectric constant characteristics (see Table 1).

[Examples 5 to 9]

As shown in Table 2 below, a flexible printed circuit board was prepared by carrying out primer composition, roughening process, and method of implementing a seed layer.

[Comparative Examples 4 to 6]

The flexible circuit boards were fabricated as shown in Table 2 below.

[Experimental Example 2] Evaluation of physical properties (2)

The following tests were conducted on the flexible printed circuit boards prepared in Examples 5 to 9 and Comparative Examples 4 to 6, respectively, and the results are shown in Table 2 below.

1) Surface roughness: To measure the surface roughness, the Ra value was measured using a non-contact 3D Optical Profiler (Bruker Contour GT). The Ra value is an average value of the heights calculated over the entire measurement area. More specifically, the absolute value of the heights varying in the measurement area is measured and arithmetically averaged from the surface of the average line. Here, This is the value measured by obtaining the roughness.

2) Line / Space: It is a value measured by a microscope to measure the line width and the width of a pattern implemented by the semi-

3) Peel Strength: Peel Strength was measured according to the test standard of IPC-TM-650 2.4.8 in order to measure the bond strength between the plated layer and the insulator.

4) Peel Strength: Peel strength was measured in accordance with the test standard of IPC-TM-650 2.4.8 after standing for 168 hours in a 150 ° C oven to measure the adhesive strength between the plated layer and the insulator at high temperature thermal shock.

5) Rate of change: In order to quantify the change of the plating adhesion measured after high temperature thermal shock, the adhesive strength changed by high temperature thermal shock was subtracted by the initial adhesive force, and then divided by the percentage.

As a result of the test, the insulating resin sheet of the present invention exhibited excellent properties in terms of surface roughness, plating adhesion, high-temperature adhesive force and rate of change (see Table 2). Accordingly, it is possible to manufacture a build-up printed circuit board with high reliability in the future, and it is considered to be usefully used as a constituent material of a small and lightweight new semiconductor package.

Claims (21)

Polyimide films;
A polyphenylene ether (PPE) resin insulating layer formed on one or both surfaces of the polyimide film; And
A thermoplastic polyimide layer formed on the polyphenylene ether (PPE) resin insulating layer and having a predetermined surface roughness formed on the surface thereof;
And an insulating resin sheet for forming a flexible printed circuit board (FPCB). The method of claim 1, wherein the polyphenylene ether (PPE) resin insulating 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)
Wherein the thermosetting resin composition is formed by curing the thermosetting resin composition. The thermosetting resin composition according to claim 2, wherein the thermosetting resin composition comprises a polyphenylene ether modified resin (a) modified by subjecting a high molecular weight polyphenylene ether to redistribution reaction in the presence of 9,9-bis (hydroxyaryl) fluorene (BCF) (E) a flame retardant. The insulating resin sheet for forming a flexible printed circuit board (FPCB) according to claim 1, The polyphenylene ether-modified resin (a) according to claim 2, wherein the polyphenylene ether-modified resin (a) is subjected to a redistribution reaction of a high molecular weight polyphenylene ether resin having a number average molecular weight in the range of 10,000 to 30,000, (FPCB). &Lt; RTI ID = 0.0 &gt; 11. &lt; / RTI &gt; The insulating resin sheet for forming a flexible printed circuit board (FPCB) according to claim 2, wherein the epoxy resin (b) is a mixture of two or more kinds of epoxy resins different in epoxy equivalent. 6. The epoxy resin composition according to claim 5, 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, based on the total weight of the insulating resin sheet. The insulating resin sheet for forming a flexible printed circuit board (FPCB) according to claim 2, wherein the curing agent (c) is selected from the group consisting of phenol-based, anhydride-based, and dicyanamide-based curing agents. The flexible printed circuit board (FPCB) according to claim 2, 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 flexible printed circuit board (FPCB) 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, silicone flame retardants and metal hydroxides. ) Insulating resin sheet. 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 modified by subjecting the high molecular weight polyphenylene ether to redistribution reaction in the presence of 9,9-bis (hydroxyaryl) fluorene (BCF) Further comprising a flame retardant (e) in the range of 5 to 40 parts by weight relative to 10 to 60 parts by weight of the insulating resin sheet. The insulating resin sheet for forming a flexible printed circuit board (FPCB) according to claim 1, wherein the thermoplastic polyimide layer has a surface roughness (Ra) in the range of 0.2 to 3.0 占 퐉. The thermoplastic polyimide resin composition according to claim 1, wherein the thermoplastic polyimide layer is formed by applying a resin composition comprising at least one resin selected from the group consisting of polyimide, polyamide, polyamideimide, and polyamic acid resin, Characterized in that the insulating resin sheet for forming a flexible printed circuit board (FPBC). The film according to claim 1, wherein the thickness of the polyimide film is in the range of 5 탆 to 100 탆,
The thickness of the polyphenylene ether (PPE) resin insulating layer is in the range of 1 탆 to 50 탆,
Wherein the thickness of the thermoplastic polyimide layer 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 To 200 [mu] m. The insulating resin sheet for forming a flexible printed circuit board (FPBC) The insulating resin sheet for forming a flexible printed circuit board (FPBC) according to claim 1, further comprising a support layer on the thermoplastic polyimide layer. 16. The insulating resin sheet for forming a flexible printed circuit board (FPBC) according to claim 15, further comprising a release layer between the thermoplastic polyimide layer and the support layer. An insulating resin sheet according to any one of claims 1 to 16; And
A copper foil layer formed on the upper and lower surfaces of the thermoplastic polyimide layer of the insulating resin sheet,
(FCCL). An insulating resin sheet according to any one of claims 1 to 16;
A copper foil plating layer formed on the upper and lower surfaces of the thermoplastic polyimide 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 flexible printed circuit board. (i) coating a thermosetting resin composition for forming a polyphenylene ether (PPE) resin insulating layer on one side or both sides of a polyimide film and then drying to form a polyphenylene ether (PPE) resin insulating layer;
(Ii) coating a composition for forming a thermoplastic polyimide layer on the polyphenylene ether (PPE) resin insulating layer and then drying to form a thermoplastic polyimide layer; And
(Iii) stacking the polyimide film and a copper foil having a predetermined surface roughness, wherein the thermoplastic polyimide layer of the polyimide film and the surface roughness of the copper foil are brought into contact with each other, Wherein the step of transferring the surface roughness of the surface
The method of manufacturing an insulating resin sheet for forming a flexible printed circuit board (FPBC) according to claim 1, The method for manufacturing a flexible printed circuit board according to claim 19, wherein the step (iii) comprises curing the composition for forming a thermoplastic polyimide layer by a roll lamination or a pressing process. &Lt; / RTI &gt; (I) forming at least one hole in the insulating resin sheet according to any one of claims 1 to 16;
(II) dishing the surface and the inside of the insulating resin sheet to form an illuminance;
(III) forming an electroless plating layer on the rough surface and the inner surface of the hole of the insulating resin sheet;
(IV) forming a pattern using a photoresist on the electroless plating layer formed;
(V) forming a circuit layer by electrolytic plating on the pattern; And
(VI) peeling the photoresist and removing the exposed electroless plating layer
Wherein the flexible printed circuit board comprises a flexible printed circuit board.

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