JP2014101491A - Resin composition for insulation, insulation film, prepreg and printed circuit board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition for insulation having low thermal expansion, high glass transition temperature, high rigidity as well as heat resistance and mechanical strength, capable of securing process property which can form low roughness for forming a fine circuit pattern in a state where low dielectric constant and hygroscopicity are basically secured, and to provide an insulation film, a prepreg and a printed circuit board.SOLUTION: The resin composition for insulation contains a liquid crystal oligomer to which nano clay binds, an epoxy resin and an inorganic filler.

Description

  The present invention relates to an insulating resin composition, an insulating film, a prepreg, and a printed circuit board.

  In recent years, with the development of electronic devices and demands for complicated functions, printed circuit boards have been reduced in weight, thickness, and size. In order to satisfy such a requirement, the wiring of the printed circuit is further complicated, and the density and functionality are increased.

  As described above, with downsizing and high performance of electronic devices, multilayer printed circuit boards are required to have high density, high functionality, downsizing, thinning, and the like. In particular, the development direction of multilayer printed circuit boards is also matched to the miniaturization and high density of wiring. As a result, thermal, mechanical, and electrical characteristics are important for the insulating layer of the multilayer printed circuit board.

  In particular, in order to minimize warpage caused by reflow during the mounting process of the electronic / electrical element, a low coefficient of thermal expansion (Low CTE), a high glass transition temperature (High Tg), a high modulus ( High Modulus characteristics are required.

  With the development of electronic devices, various methods have been studied in order to improve the mechanical, electrical, and thermal characteristics of insulating layers in multilayer printed circuit boards used in electronic devices. For example, in order to increase the adhesive strength of insulating materials for printed circuit boards, and to realize a low thermal expansion coefficient and high strength (modulus), a resin layer such as epoxy resin, polyimide, aromatic polyester, etc., ceramic such as silica or alumina An insulating material is manufactured by filling a filler, but the degree is not sufficient.

  On the other hand, researches are currently underway to improve thermal and mechanical properties by introducing inorganic materials such as nano-sized clay into olefin resins. However, it is not easy for nano-sized inorganic substances to have high dispersibility, and the characteristics are not sufficiently realized.

  For example, Patent Document 1 discloses a fuel for a natural gas vehicle obtained by melt-mixing a mixture of a lipophilic nanoclay and a polypropylene resin modified with maleic anhydride with a polyethylene resin again. Although a method for producing a polyethylene composite material for a storage container has been disclosed, this is not suitable as an insulating resin used in electronic products such as printed circuit boards.

  Therefore, at present, there is a demand for an insulating layer that can satisfy the requirements of a printed circuit board that is further complicated in wiring of the printed circuit and is becoming higher in density and functionality.

Korean Registered Patent No. 10-0491213

  In order to realize a low thermal expansion coefficient and high rigidity of a printed circuit board, the present inventors have used a resin composition for insulation containing an epoxy resin and a liquid crystal oligomer which is reacted with nanoclay and bonded with nanoclay, to reduce the low heat of the printed circuit board. In addition to expansion coefficient, high glass transition temperature, and high rigidity, it has heat resistance and mechanical strength, and low roughness to form fine circuit patterns in a state where low dielectric constant and hygroscopicity are basically secured. Based on this, the present invention was completed.

  Accordingly, one object of the present invention is to provide an insulating resin composition that is excellent in heat resistance and mechanical properties in combination with a low coefficient of thermal expansion, a high glass transition temperature, and high rigidity.

  Another object of the present invention is to provide an insulating film which is manufactured from the resin composition and has improved heat resistance and mechanical properties in combination with a low coefficient of thermal expansion, a high glass transition temperature and high rigidity.

  Still another object of the present invention is to provide a prepreg in which a base material is impregnated with the resin composition to improve heat resistance and mechanical properties in combination with a low coefficient of thermal expansion, a high glass transition temperature, and high rigidity. .

  Still another object of the present invention is to provide a printed circuit board, preferably a multilayer printed circuit board, including the insulating film or the prepreg.

  An insulating resin composition according to the present invention (first invention) for achieving the one object includes a liquid crystal oligomer to which nanoclay is bonded, an epoxy resin, and an inorganic filler.

  In the first invention, the liquid crystal oligomer is represented by the following chemical formula 1, chemical formula 2, chemical formula 3 or chemical formula 4.

  In the chemical formulas 1 to 4, a is an integer of 13 to 26, b is an integer of 13 to 26, c is an integer of 9 to 21, d is an integer of 10 to 30, and e is 10 It is an integer of ~ 30.

  1st invention WHEREIN: The said epoxy resin is represented by following Chemical formula 5 or Chemical formula 6, It is characterized by the above-mentioned.

  In the chemical formula 1, R is an alkyl group having 1 to 20 carbon atoms, and n is an integer of 0 to 20.

  1st invention WHEREIN: The said resin composition for insulation contains the liquid crystal oligomer 0.5-50 weight% containing the said nano clay, the said epoxy resin 5-50 weight%, and the said inorganic filler 40-80 weight%. It is characterized by.

  In the first invention, the insulating resin composition further includes 0.1 to 1 part by weight of a curing agent with respect to 100 parts by weight of the liquid crystal oligomer and the epoxy resin.

In the first invention, the nanoclay is a natural nanoclay surface-treated with Ca ⁺ or Na ⁺ among montmorillonite.

  In the first invention, the nanoclay is surface-treated with a quaternary ammonium salt to which an aliphatic carbon chain or an alkyl group is added (Quaternary Ammonium Salt).

  In the first invention, the insulating resin composition is selected from a naphthalene epoxy resin, a bisphenol A epoxy resin, a phenol novolac epoxy resin, a cresol novolac epoxy resin, a rubber-modified epoxy resin, and a phosphorous epoxy resin. It further includes one or more epoxy resins.

  In the first invention, the curing agent is selected from an amide curing agent, a polyamine curing agent, an acid anhydride curing agent, a phenol novolac curing agent, a polymercaptan curing agent, a tertiary amine curing agent, or an imidazole curing agent. It is one or more.

  In the first invention, the inorganic filler is silica, alumina, barium sulfate, talc, clay, mica powder, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum borate, titanium. It is one or more selected from the group consisting of barium acid, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, barium zirconate and calcium zirconate.

  1st invention WHEREIN: The diameter of the said inorganic filler is 0.008-10 micrometers, It is characterized by the above-mentioned.

  In the first invention, the insulating resin composition comprises 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4- Methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-un Decylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecyl-imidazolium trimellitate, 1-cyanoethyl-2-phenyl-imidazolium trimellitate, 2,4-diamino-6- (2 '-Methylimidazole- ( ′))-Ethyl-es-triazine, 2,4-diamino-6- (2′ethyl-4-methylimidazole- (1 ′))-ethyl-es-triazine, 2,4-diamino-6- (2 '-Undecylimidazole- (1'))-ethyl-es-triazine, 2-pecyl-4,5-dihydroxymethylimidazole, 2-pecyl-4-methyl-5-hydroxymethyl, 2-pecyl-4-benzyl -5-hydroxymethylimidazole, 4,4'-methylene-bis- (2-ethyl-5-methylimidazole), 2-aminoethyl-2-methylimidazole, 1-cyanoethyl-2-phenyl-4,5-di From (cyano-ethoxymethyl) imidazole, 1-dodecyl-2-methyl-3-benzylimidazolinium chloride and imidazole-containing polyamide It further comprises one or more selected curing accelerators.

  In the first invention, the insulating resin composition includes phenoxy resin, polyimide resin, polyamideimide (PAI) resin, polyetherimide (PEI) resin, polysulfone (PS) resin, polyethersulfone (PES) resin, polyphenylene ether. It further includes at least one thermoplastic resin selected from (PPE) resin, polycarbonate (PC) resin, polyether ether ketone (PEEK) resin, and polyester resin.

  An insulating film (second invention) for achieving the other object of the present invention is manufactured from the insulating resin composition.

  A prepreg (third invention) for achieving another object of the present invention is produced by impregnating the insulating resin composition described above.

  A printed circuit board, particularly a multilayer printed circuit board, for achieving another object of the present invention includes an insulating film according to the second invention.

  A printed circuit board, particularly a multilayer printed circuit board, for achieving another object of the present invention includes a prepreg according to the third invention.

  The insulating resin composition according to the present invention, and the insulating film and prepreg produced using the insulating resin composition have low thermal expansion coefficient, high glass transition temperature, high rigidity, heat resistance and mechanical strength, and low dielectric constant. The processability which can form the low roughness for forming a fine circuit pattern in the state by which the rate and the hygroscopic property were fundamentally ensured can be ensured.

It is sectional drawing of the copper clad laminated board which formed copper foil on the prepreg manufactured with the resin composition for insulation by this invention. It is sectional drawing of the normal printed circuit board which can apply the resin composition for insulation by this invention.

  Objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments with reference to the accompanying drawings. In this specification, it should be noted that when adding reference numerals to the components of each drawing, the same components are given the same number as much as possible even if they are shown in different drawings. I must. The terms “one side”, “other side”, “first”, “second” and the like are used to distinguish one component from another component, and the component is the term It is not limited by. Hereinafter, in describing the present invention, detailed descriptions of known techniques that may obscure the subject matter of the present invention are omitted.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  1 and 2, a printed circuit board according to a preferred embodiment of the present invention uses a copper clad laminate 30 in which a copper foil 20 is formed on a prepreg 10 made of a resin composition according to the present invention. An insulator 11 having a cavity, for example, an insulating film or a prepreg, and another insulator 12 and / or 13 disposed on at least one of the upper and lower surfaces of the insulator 11, for example, a build-up layer. Can be included. The build-up layer includes an insulator 12 disposed on at least one of the upper surface and the lower surface of the insulator 11, and circuit layers 21 and 22 disposed on the insulator 13 to form an interlayer connection.

  Here, the insulators 10, 11, 12, and 13 can function to provide insulation between circuit layers or electronic components, and can also function as a structural material for maintaining the rigidity of the package.

  At this time, in order to minimize the distortion of the printed circuit board 100, preferably a multilayer printed circuit board, which is caused by reflow during the mounting process of the electronic and electrical elements, the insulators 10, 11, 12 and 13 require thermal, mechanical and electrical properties such as low coefficient of thermal expansion, high glass transition temperature and high modulus. The insulators 10, 11, 12 and 13 according to the present invention can form a low roughness for forming a fine circuit pattern in a state where a low dielectric constant and hygroscopicity are basically ensured.

  Thus, in order to ensure the excellent thermal, mechanical and electrical properties of the insulators 10, 11, 12 and 13 in the present invention, the insulator includes a liquid crystal oligomer to which nanoclay is bonded, and an epoxy resin. And an insulating resin composition containing an inorganic filler. Optionally, the insulating resin composition according to the present invention may further include a curing agent, a curing accelerator, another epoxy resin, and / or other additives.

(Nano clay)
Nanoclays overlap in a plate shape at intervals of several nanometers, and are called so-called layered silicate inorganic materials. The present invention relates to a polymer nanocomposite material that can improve the physical properties of the polymer by reacting the nanoclay with a polymer (for example, an oligomer) and introducing the nanoclay into the polymer. However, it is difficult for the polymer nanocomposite material to have high dispersibility. Therefore, the present invention provides a technique capable of increasing the interlayer distance of the nanoclay and ensuring compatibility with the polymer while synthesizing a liquid crystal oligomer bonded by reacting the nanoclay with the liquid crystal oligomer.

Examples of the nanoclay used in the present invention include natural nanoclay surface-treated with Ca ⁺ or Na ⁺ in montmorillonite, or a quaternary ammonium salt to which an aliphatic carbon chain or an alkyl group is added. Although nanoclay surface-treated with (Quaternary Ammonium Salt) is preferable, it is not particularly limited thereto. Such nanoclay is preferably used in a weight ratio of 0.1% to 10% with respect to the liquid crystal oligomer. When the amount of the liquid crystal oligomer used is less than 0.1%, the thermal expansion coefficient decreases and the glass transition temperature. In the case where the increase in the amount is small and exceeds 10%, the viscosity of the solution in which the liquid crystal oligomer is dissolved tends to increase and the processability tends to decrease.

(Liquid crystal oligomer)
The liquid crystal oligomer used in the present invention may be a compound represented by the following chemical formula 1, chemical formula 2, chemical formula 3, or chemical formula 4.

  In the chemical formulas 1 to 4, a is an integer of 13 to 26, b is an integer of 13 to 26, c is an integer of 9 to 21, d is an integer of 10 to 30, and e is 10 It is an integer of ~ 30.

  The liquid crystal oligomers represented by the chemical formulas 1 to 4 contain ester groups at both ends of the main chain in order to improve the dielectric loss tangent and dielectric constant, and contain naphthalene groups for crystallinity, As shown in Chemical Formula 2 or Chemical Formula 4, a phosphorus component that imparts flame retardancy can be contained. More specifically, the liquid crystal oligomer may contain a hydroxyl group or a nadiimide group at a terminal to perform a thermosetting reaction with an epoxy or a bismaleimide.

  On the other hand, in order to synthesize a liquid crystal oligomer with nanoclay bonded, the monomer used must have a functional group that can participate in the reaction during the polymerization process, and is inserted between the nanoclay layers. It must have the property of increasing the interlayer distance. Such monomers must contain carboxyl groups (—COOH) or anhydrides (Anhydrides) and hydroxy groups (—OH). The liquid crystal oligomer to which nanoclay is bonded contains a hydroxyl group at the terminal and can be thermally cured with an epoxy. The oligomer includes an amide group that imparts solubility, a naphthalene group that imparts liquid crystallinity, and the compounds represented by Chemical Formulas 2 and 4 may include a phosphorus component to realize flame retardancy. In the chemical formulas 1 to 4, a, b, c, d, and e mean the molar ratio of repeating units, and are determined by the content of the starting material.

  The number average molecular weight of the liquid crystal oligomer is preferably 2,500 to 6,500 g / mol, more preferably 3,000 to 6,000 g / mol, and most preferably 3,000 to 5,000 g / mol. When the number average molecular weight of the liquid crystal oligomer is less than 2,500 g / mol, there is a problem that the mechanical properties are inferior, and when it exceeds 6,500 g / mol, there is a problem that the solubility is lowered.

  The amount of the liquid crystal oligomer to which the nanoclay is bonded is preferably 0.5 to 50% by weight, and more preferably 15 to 40% by weight. When the amount used is less than 0.5% by weight, the reduction of the thermal expansion coefficient and the improvement of the glass transition temperature are minute, and when it exceeds 50% by weight, the mechanical properties tend to be lowered.

(Epoxy resin)
The resin composition according to the present invention contains an epoxy resin in order to enhance the handleability of the resin composition after drying as an adhesive film. The epoxy resin is not particularly limited, but it means that one or more epoxy groups are contained in the molecule, preferably means that two or more epoxy groups are contained in the molecule, and more preferably, In which 4 or more epoxy groups are contained.

  The epoxy resin used in the present invention preferably includes a naphthalene group as shown in the following chemical formula 5 or an aromatic amine type as shown in the following chemical formula 6.

  In the chemical formula 5, R is an alkyl group having 1 to 20 carbon atoms, and n is an integer of 0 to 20.

  However, the epoxy resin used in the present invention is not particularly limited to the epoxy resin represented by the chemical formula 5 or the chemical formula 6, and examples thereof include bisphenol A type epoxy resin, bisphenol F type epoxy resin, and bisphenol S type epoxy resin. , Phenol novolac type epoxy resin, alkylphenol novolak type epoxy resin, cresol novolac epoxy resin, biphenyl type epoxy resin, aralkyl type epoxy resin, dicyclopentadiene type epoxy resin, naphthalene type epoxy resin, naphthol type epoxy resin, phenols and phenol Condensates with aromatic aldehydes having a functional hydroxyl group, biphenyl aralkyl type epoxy resins, fluorene type epoxy resins, xanthene type epoxy resins, triglycidyl resins Cyanurate, and rubber-modified epoxy resin and phosphorus (Phosphorous) epoxy resins can be used. The epoxy resins may be used alone or in combination of two or more. Preferably, it is at least one selected from naphthalene type epoxy resin, bisphenol A type epoxy resin, phenol novolac epoxy resin, cresol novolac epoxy resin, rubber-modified epoxy resin and phosphorus type epoxy resin.

  The amount of the epoxy resin used is preferably 5 to 50% by weight. When the amount used is less than 5% by weight, the handleability is lowered. And the degree of improvement of dielectric loss tangent, dielectric constant and coefficient of thermal expansion tends to decrease.

(Inorganic filler)
The resin composition according to the present invention contains an inorganic filler in order to reduce the coefficient of thermal expansion (CTE) of the epoxy resin. The inorganic filler lowers the thermal expansion coefficient, and the content ratio with respect to the resin composition varies depending on the properties required in consideration of the use of the resin composition, but is preferably 40 to 80% by weight. When it is less than 40% by weight, the dielectric loss tangent is low and the coefficient of thermal expansion is high, and when it exceeds 80% by weight, the adhesive strength tends to decrease.

  Specific examples of the inorganic filler used in the present invention include silica, alumina, barium sulfate, talc, clay, mica powder, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, Aluminum borate, barium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, barium zirconate, calcium zirconate and the like can be used alone or in combination of two or more. In particular, silica having a low dielectric loss tangent is preferable.

  The inorganic filler can be dispersed in a size of several nanometers to several tens of micrometers, or can be mixed and used without being dispersed. When the average particle diameter exceeds 10 μm, it is difficult to stably form a fine pattern when forming a circuit pattern on the conductor layer. Therefore, the average particle diameter is more preferably 10 μm or less. The inorganic filler is preferably surface-treated with a surface treatment agent such as a silane coupling agent in order to improve moisture resistance. More preferably, silica having a diameter of 0.008 to 5 μm is suitable.

(Curing agent)
On the other hand, in this invention, a hardening | curing agent can be used selectively, and normally any can be used if it can be used in order to thermoset an epoxy resin, It does not specifically limit.

  Specifically, amide type curing agents such as dicyandiamide; polyamine type curing agents such as diethylenetriamine, triethylenetetraamine, N-aminoethylpiperazine, diaminodiphenylmethane, adipic acid dihydrazide, etc .; acid anhydride curing agents such as pyrometalic acid Anhydride, benzophenone tetracarboxylic acid anhydride, ethylene glycol bistrimetalic acid anhydride, glycerol tristrimetalic acid anhydride, maleic methylcyclohexane tetracarboxylic acid anhydride, etc .; phenol novolac type curing agent; Xatriethylene mercaptan, etc .; tertiary amine curing agents such as benzyldimethylamine, 2,4,6-tris (dimethylaminomethyl) phenol; 4-methylimidazole, 2-methylimidazole, 1-benzyl-2-methylimidazole, 2-heptadecylimidazole, 2-undecylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2-phenyl Examples include imidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-phenylimidazole, 1,2-dimethylimidazole, 1-cyanoethyl-2-phenylimidazole, and 2-phenyl-4,5-dihydroxymethylimidazole. The curing agent can be used alone or in combination of two or more. In particular, dicyandiamide is preferable in terms of physical properties. The amount of the curing agent used is within a range well known to those skilled in the art, for example, within the range of 0.1 to 1 part by weight of the curing agent with respect to 100 parts by weight of the mixture of the liquid crystal oligomer and the epoxy resin. Without degrading the intrinsic physical properties of the resin, it can be appropriately selected and used in consideration of the curing rate.

(Curing accelerator)
The resin composition of the present invention can efficiently cure the epoxy resin of the present invention by selectively containing a curing accelerator. Examples of the curing accelerator used in the present invention include a metal-based curing accelerator, an imidazole-based curing accelerator, an amine-based curing accelerator, and the like, and these are one or a combination of two or more of ordinary amounts well known in the art. Can be used.

  Although it does not restrict | limit especially as said metal-enhanced hardening accelerator, The organometallic complex or organometallic salt of metals, such as cobalt, copper, zinc, iron, nickel, manganese, tin, is mentioned. Specific examples of the organometallic complex include organocobalt complexes such as cobalt (II) acetylacetonate and cobalt (III) acetylacetonate, glass copper complexes such as copper (II) acetylacetonate, and zinc (II) acetyl. Organic zinc complexes such as acetonate, organic iron complexes such as iron (III) acetylacetonate, organic nickel complexes such as nickel (II) acetylacetonate, and organic manganese complexes such as manganese (II) acetylacetonate . Examples of the organic metal salt include zinc octylate, tin octylate, zinc naphthenate, cobalt naphthenate, tin stearate, and zinc stearate. As the metal-dependent curing accelerator, in terms of curability and solvent solubility, cobalt (II) acetylacetonate, cobalt (III) acetylacetonate, zinc (II) acetylacetonate, zinc naphthenate, iron (III) Acetylacetonate is preferable, and cobalt (II) acetylacetonate and zinc naphthenate are particularly preferable. One or more metal-enhanced curing accelerators can be used in combination.

  The imidazole curing accelerator is not particularly limited, but 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 1,2 -Dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2 -Methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1- Anoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6- [2'-methylimidazolyl- (1 ')]-ethyl-s-triazine, 2,4-diamino-6- [2'- Undecylimidazolyl- (1 ′)]-ethyl-s-triazine, 2,4-diamino-6- [2′-ethyl-4′-methylimidazolyl- (1 ′)]-ethyl-s-triazine, 2, 4-diamino-6- [2'-methylimidazolyl- (1 ')]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-Phenyl-4-methyl-5hydroxymethylimidazole, 2,3-dihydroxy-1H-pyrrolo [1,2-a] benzimidazole, 1-dodecyl-2-methyl 3-benzyl-imidazolium chloride, 2-methyl-imidazoline, imidazole compounds such as 2-phenyl-imidazoline and imidazole compounds and adducts of epoxy resins. One or more imidazole curing accelerators can be used in combination.

  The amine curing accelerator is not particularly limited, but trialkylamine such as triethylamine and tributylamine, 4-dimethylaminopyridine, benzyldimethylamine, 2,4,6-tris (dimethylaminomethyl) phenol, 1, And amine compounds such as 8-diazabicyclo (5,4,0) -undecene (hereinafter referred to as DBU). One or a combination of two or more amine curing accelerators can be used.

(Thermoplastic resin)
The resin composition of the present invention can selectively contain a thermoplastic resin in order to improve the film properties of the resin composition or to improve the mechanical properties of the cured product. Examples of thermoplastic resins include phenoxy resin, polyimide resin, polyamideimide (PAI) resin, polyetherimide (PEI) resin, polysulfone (PS) resin, polyethersulfone (PES) resin, polyphenylene ether (PPE) resin, polycarbonate (PC) resin, polyether ether ketone (PEEK) resin, polyester resin, etc. are mentioned. These thermoplastic resins are used alone or in admixture of two or more. The weight average molecular weight of the thermoplastic resin is preferably in the range of 5,000 to 200,000. When the amount is less than 5,000, the effect of improving the film formability and mechanical strength tends to be insufficient. When the amount is more than 200,000, the compatibility with the liquid crystal oligomer and the epoxy resin is insufficient, and the surface unevenness after curing. Increases, which makes it difficult to form a high-density fine pattern.

  When a thermoplastic resin is blended in the resin composition of the present invention, the content of the thermoplastic resin in the resin composition is not particularly limited, but is 0.1 to 0.1% by weight with respect to 100% by weight of the nonvolatile content in the resin composition. 10 weight% is preferable, More preferably, it is 1 to 5 weight%. When the content of the thermoplastic resin is less than 0.1% by weight, the effect of improving the film formability and mechanical strength tends to not be exhibited. When the content exceeds 10% by weight, the melt viscosity is increased and after the wet roughening step. The surface roughness of the insulating layer tends to increase.

  The insulating resin composition according to the present invention is mixed in the presence of an organic solvent. As the organic solvent, considering the solubility and miscibility of the resin and other additives used in the present invention, dimethylformamide, dimethylacetamide, 2-methoxyethyl alcohol, acetone, methyl ethyl ketone, cyclohexanone, ethyl acetate, butyl acetate, Examples include cellosolve acetate, propylene glycol mono-methyl ether acetate, ethylene glycol mono-butyl ether acetate, cellosolve, butyl cellosolve, carbitol, butyl carbitol, and xylene, but are not particularly limited thereto.

  The viscosity of the resin composition according to the present invention is preferably 700 to 1500 cps for producing an insulating film, and has a characteristic of maintaining an appropriate viscosity at room temperature. The viscosity of the resin composition of the present invention can be adjusted by changing the content of a solvent (for example, DMAc). Nonvolatile components other than the solvent occupy 30 to 70% by weight with respect to the resin composition. When the viscosity of the resin composition is out of the above range, it may be difficult to form an insulating film, or even if formed, it may be difficult to mold a member.

  Moreover, peel strength shows 1.0 kN / m or more, when a 12 micrometer copper foil is used in the state of an insulating film. The insulating film manufactured with the resin composition according to the present invention has a coefficient of thermal expansion (CTE) measured in the temperature range of 50 to 150 ° C. of less than 28 ppm / ° C., and a coefficient of thermal expansion (CTE) measured above the glass transition temperature. ) Has a value of less than 80 ppm / ° C. The tensile strength is 10 or more, and the glass transition temperature (Tg) is 200 to 300 ° C, preferably 230 to 270 ° C.

  In addition, the present invention may further include other leveling agents and / or flame retardants known to those who have ordinary knowledge in the art within the technical idea of the present invention, if necessary.

  The insulating resin composition of the present invention can be produced into a semi-solid dry film by any general method known in the art. For example, after manufacturing in a film form using a roll coater (Roll Coater) or a curtain coater (Curtain Coater) and drying, when this is applied on a substrate, a multilayer printed board by a build-up method is manufactured. Used as an insulating layer (or insulating film) or prepreg. Such an insulating film or prepreg has a low coefficient of thermal expansion (CTE) of 30 ppm / ° C. or less.

  As described above, the resin composition according to the present invention is impregnated into a base material such as glass fiber, and then cured to produce a prepreg, and a copper foil is laminated on the copper-clad laminate (CCL) as shown in FIG. : copper clad laminate) 30 is acquired. In addition, when the insulating film manufactured with the resin composition according to the present invention is laminated on the CCL used as the inner layer when manufacturing the multilayer printed circuit board, the multilayer printed circuit board 100 as shown in FIG. 2 is manufactured. Used for. For example, after laminating an insulating film made of the insulating resin composition on a patterned inner layer circuit board, curing it at a temperature of 80 to 110 ° C. for 20 to 30 minutes, and performing a desmear process, a circuit layer Can be formed by an electroplating process to produce a multilayer printed circuit board.

  Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples, but the scope of the present invention is not limited to the following examples.

(Synthesis Example 1)
[Synthesis of a liquid crystal oligomer having a hydroxy group at the end to which nanoclay is bonded]
In a 5 L glass reactor, 545.65 g (5.0 mol) of 4-aminophenol, 622.99 g (3.75 mol) of isoptaric acid, 402.28 g (2.91 mol) of 4-hydroxybenzoic acid, 6-hydroxy-2- After adding 195.24 g (1.04 mol) of naphthoic acid and 1566.55 g (15.35 mol) of acetic anhydride, 108 g of nanoclay is added. The glass reactor is equipped with a sealed mechanical stirrer, nitrogen injection tube, thermometer and reflux condenser. After sufficiently replacing the inside of the reactor with nitrogen gas, the temperature inside the reactor is raised to a temperature of about 140 ° C. under the flow of nitrogen gas, and refluxed for 3 hours while maintaining the temperature inside the reactor at the above temperature. Let Next, acetic acid and unreacted acetic anhydride as reaction byproducts are removed and the temperature is raised to about 250 ° C. After further adding 352.84 g (1.88 mol) of 6-hydroxy-2-naphthoic acid at the above temperature, the temperature was raised to about 280 ° C., followed by reaction for about 3 hours to obtain a molecular weight having a hydroxy group at the terminal of about A liquid crystal oligomer represented by the above chemical formula 1 of 4600 g / mol was produced.

(Synthesis Example 2)
[Synthesis of Liquid Crystalline Oligomer Showing High Glass Transition Temperature with Hydroxyl Terminal at Nanoclay Bonded End]
In a 5 L glass reactor, 545.65 g (5.0 mol) of 4-aminophenol, 726.82 g (4.38 mol) of isoptaric acid, 402.28 g (2.91 mol) of 4-hydroxybenzoic acid, 6-hydroxy-2- After adding 371.66 g (1.98 mol) of naphthoic acid and 1671.85 g (16.38 mol) of acetic anhydride, 108 g of nanoclay is added. The glass reactor is equipped with a sealed mechanical stirrer, nitrogen injection tube, thermometer and reflux condenser. After sufficiently replacing the inside of the reactor with nitrogen gas, the temperature in the reactor is raised to a temperature of about 140 ° C. under a flow of nitrogen gas, and the temperature inside the reactor is maintained at the temperature for about 3 hours. Reflux. Next, acetic acid and unreacted acetic anhydride as reaction byproducts are removed and the temperature is raised to about 250 ° C. After further adding 176.42 g (0.938 mol) of 6-hydroxy-2-naphthoic acid at the above temperature, the temperature was raised to about 280 ° C., followed by reaction for about 3 hours to obtain a molecular weight having a hydroxy group at the terminal of about A liquid crystal oligomer represented by Formula 1 that is 4800 g / mol is produced.

(Synthesis Example 3)
[Synthesis of Liquid Crystal Oligomer with Nano-Clay Bonded Terminal Nadiimide]
In a 5 L glass reactor, 68.21 g (0.6 mol) of 4-aminophenol, 207.66 g (1.25 mol) of isoptaric acid, 338.40 g (2.45 mol) of 4-hydroxybenzoic acid, 6-hydroxy-2- Naphthoic acid 461.04 g (2.45 mol), 2- (6-oxide-6H-dibenz [c, e] [1,2oxaphospholin-6-yl) -1,4-benzenediol, DOPO-HQ) After adding 608.01 g (1.88 mol) and 111.76 g (10.89 mol) of acetic anhydride, 108 g of nanoclay is added. The glass reactor is equipped with a sealed mechanical stirrer, nitrogen injection tube, thermometer and reflux condenser. After sufficiently replacing the inside of the reactor with nitrogen gas, the temperature in the reactor is raised to a temperature of about 140 ° C. under a flow of nitrogen gas, and the temperature inside the reactor is maintained at the temperature for about 3 hours. Reflux. After completing the acetylation reaction, the temperature inside the reactor is raised to about 200 ° C. while distilling off the by-products to be removed, acetic acid and unreacted acetic anhydride. After adding 708.2 g (2.5 mol) of end-capping nadiimide benzoic acid at the above temperature, the reaction was allowed to proceed at about 200 ° C. for about 3 hours, and the polymerization reaction was further advanced while gradually applying vacuum for the last 30 minutes. A liquid crystal thermosetting oligomer represented by Formula 2 having an end-capped molecular weight of about 4700 g / mol was prepared.

(Comparative Synthesis Example 1)
[Synthesis of liquid crystal oligomer without nanoclay]
In a 5 L glass reactor, 545.65 g (5.0 mol) of 4-aminophenol, 622.99 g (3.75 mol) of isoptaric acid, 402.28 g (2.91 mol) of 4-hydroxybenzoic acid, 6-hydroxy-2- 195.24 g (1.04 mol) of naphthoic acid and 1566.55 g (15.35 mol) of acetic anhydride are added. The glass reactor is equipped with a sealed mechanical stirrer, nitrogen injection tube, thermometer and reflux condenser. After sufficiently replacing the inside of the reactor with nitrogen gas, the temperature in the reactor is raised to a temperature of about 140 ° C. under a flow of nitrogen gas, and the temperature inside the reactor is maintained at the temperature for about 3 hours. Reflux. Next, acetic acid and unreacted acetic anhydride as reaction byproducts are removed and the temperature is raised to about 250 ° C. After further adding 352.84 g (1.88 mol) of 6-hydroxy-2-naphthoic acid at the above temperature, the temperature was raised to about 280 ° C., followed by reaction for about 3 hours to obtain a molecular weight having a hydroxy group at the terminal of about The liquid crystal oligomer represented by Formula 1 is 4200 g / mol.

Example 1
[Vannish production and film production using a liquid crystal oligomer with nanoclay]
A liquid crystal oligomer solution is prepared by adding 50 g of the liquid crystal oligomer obtained in Synthesis Example 1 to N, N′-dimethylacetamide (DMAc). To this, 107.09 g of silica filler slurry (NV 78.13%) is added and stirred for 30 minutes. To this, 33.3 g of Araldite MY-721 (manufactured by Huntsmann) as an epoxy resin and 0.33 g of dicyandiamide as a curing catalyst are added and stirred for 2 hours. This is applied by a doctor blade method to a copper foil shiny surface with a thickness of 100 μm to produce a film. The produced film is dried at room temperature for 2 hours, dried in a vacuum oven at 80 ° C. for 1 hour, and dried at 110 ° C. for 1 hour to form a semi-cured state (B-stage). This is fully cured using vacuum pressure. At this time, the maximum temperature was 230 ° C., and the maximum pressure was 2 MPa.

(Example 2)
[Manufacture of varnish and film using a liquid crystal oligomer combined with nanoclay]
A liquid crystal oligomer solution is prepared by adding 50 g of the liquid crystal oligomer obtained in Synthesis Example 2 to N, N′-dimethylacetamide (DMAc). To this, 107.09 g of silica filler slurry (NV 78.13%) is added and stirred for 30 minutes. To this, 33.3 g of Araldite MY-721 (manufactured by Huntsmann) as an epoxy resin and 0.33 g of dicyandiamide as a curing catalyst are added and stirred for 2 hours. This is applied by a doctor blade method to a copper foil shiny surface with a thickness of 100 μm to produce a film. The produced film is dried at room temperature for 2 hours, dried in a vacuum oven at 80 ° C. for 1 hour, and dried at 110 ° C. for 1 hour to make a semi-cured state. This is fully cured using vacuum pressure. At this time, the maximum temperature was 230 ° C., and the maximum pressure was 2 MPa.

(Example 3)
[Manufacture of varnish and film using a liquid crystal oligomer combined with nanoclay]
A liquid crystal oligomer solution is produced by adding 25 g of the liquid crystal oligomer obtained in Synthesis Example 2 and 25 g of the liquid crystal oligomer obtained in Synthesis Example 3 to N, N′-dimethylacetamide (DMAc). To this, 107.09 g of silica filler slurry (NV 78.13%) is added and stirred for 30 minutes. To this was added 16.65 g of epoxy resin Araldite MY-721 (manufactured by Huntsmann), 11.0 g of 4-4′-bismaleimide diphenylmethane (BMI-1000), and 0.33 g of dicyandiamide as a curing catalyst for 2 hours. Stir. This is applied by a doctor blade method to a copper foil shiny surface with a thickness of 100 μm to produce a film. The produced film is dried at room temperature for 2 hours, dried in a vacuum oven at 80 ° C. for 1 hour, and dried at 110 ° C. for 1 hour to make a semi-cured state. This is fully cured using vacuum pressure. At this time, the maximum temperature was 230 ° C., and the maximum pressure was 2 MPa.

(Comparative Example 1)
[Manufacture of varnishes and films with nanoclay dispersed in a forehead]
A liquid crystal oligomer solution is prepared by adding 50 g of the liquid crystal oligomer obtained in Comparative Synthesis Example 1 to N, N′-dimethylacetamide (DMAc). Add 0.84 g of nanoclay to 106.02 g of silica filler slurry (NV 78.13%) and stir at high speed for about 30 minutes. Add 33.3 g of Araldite MY-721 (manufactured by Huntsmann) as an epoxy resin and 0.33 g of dicyandiamide as a curing catalyst to the silica filler slurry containing the liquid crystal oligomer solution and nanoclay and stir for about 2 hours. This is applied by a doctor blade method to a copper foil shiny surface with a thickness of 100 μm to produce a film. The produced film is dried at room temperature for about 2 hours, dried in a vacuum oven at 80 ° C. for 1 hour, and dried at 110 ° C. for 1 hour to make a semi-cured state. This is fully cured using vacuum pressure. At this time, the maximum temperature was 230 ° C., and the maximum pressure was 2 MPa.

(Thermal characteristics evaluation)
The thermal expansion coefficient (CTE) of the specimens of the insulating films manufactured according to the examples and comparative examples are as follows: a temperature range (a1) of 50 to 150 ° C. and a glass transition temperature using a thermal analyzer (TMA; Thermo mechanical Analyzer). The coefficient of thermal expansion in the above (a2) was measured, and the glass transition temperature (Tg) was determined by differential scanning calorimetry (DSC) using a thermal analyzer (TA Instruments TMA2940) under a nitrogen atmosphere at a temperature of 10 ° C. The sample was heated up to 270 ° C./min and measured to 270 ° C. (first cycle) and 300 ° C. (second cycle), and the tensile strength was measured by dynamic mechanical analysis (DMA).

  As can be seen from Table 1, the insulating film made of the epoxy resin according to the present invention has a relatively low thermal expansion coefficient, high tensile strength, and high glass transition temperature (Tg) as compared with the film of Comparative Example 1. .

  As described above, the present invention has been described in detail based on the specific embodiments. However, the present invention is only for explaining the present invention, and the present invention is not limited thereto. It will be apparent to those skilled in the art that modifications and improvements within the technical idea of the present invention are possible.

  All simple variations and modifications of the present invention belong to the scope of the present invention, and the specific scope of protection of the present invention will be apparent from the appended claims.

  The present invention is applicable to insulating resin compositions, insulating films, prepregs and printed circuit boards.

10 Prepreg (insulator)
11, 12, 13 Insulator 20 Copper foil 21, 22 Circuit layer 30 Copper-clad laminate 100 Printed circuit board (multilayer printed circuit board)

Claims (17)

A liquid crystal oligomer combined with nanoclay;
Epoxy resin,
An insulating resin composition comprising an inorganic filler. The insulating resin composition according to claim 1, wherein the liquid crystal oligomer is represented by the following chemical formula 1, chemical formula 2, chemical formula 3 or chemical formula 4.

In the chemical formulas 1 to 4, a is an integer of 13 to 26, b is an integer of 13 to 26, c is an integer of 9 to 21, d is an integer of 10 to 30, and e is 10 It is an integer of ~ 30. The insulating resin composition according to claim 1, wherein the epoxy resin is represented by the following chemical formula 5 or chemical formula 6.

In the chemical formula 1, R is an alkyl group having 1 to 20 carbon atoms, and n is an integer of 0 to 20.

  The insulating resin composition includes 0.5 to 50% by weight of a liquid crystal oligomer to which the nanoclay is bonded, 5 to 50% by weight of the epoxy resin, and 40 to 80% by weight of the inorganic filler. Item 2. The insulating resin composition according to Item 1.   The insulating resin composition according to claim 1, wherein the insulating resin composition further includes 0.1 to 1 part by weight of a curing agent with respect to 100 parts by weight of the liquid crystal oligomer and the epoxy resin. . The insulating resin composition according to claim 1, wherein the nanoclay is a natural nanoclay surface-treated with Ca ⁺ or Na ⁺ of montmorillonite.   2. The insulating resin composition according to claim 1, wherein the nanoclay is surface-treated with a quaternary ammonium salt to which an aliphatic carbon chain or an alkyl group is added.   The insulating resin composition includes at least one epoxy resin selected from a naphthalene epoxy resin, a bisphenol A epoxy resin, a phenol novolac epoxy resin, a cresol novolac epoxy resin, a rubber-modified epoxy resin, and a phosphorus epoxy resin. The insulating resin composition according to claim 1, further comprising:   The curing agent is one or more selected from amide type curing agents, polyamine type curing agents, acid anhydride curing agents, phenol novolac type curing agents, polymercaptan curing agents, tertiary amine curing agents or imidazole curing agents. The insulating resin composition according to claim 5, wherein the resin composition is an insulating resin composition.   The inorganic filler is silica, alumina, barium sulfate, talc, clay, mica powder, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum borate, barium titanate, titanate The insulating resin composition according to claim 1, wherein the insulating resin composition is one or more selected from the group consisting of calcium, magnesium titanate, bismuth titanate, titanium oxide, barium zirconate and calcium zirconate.   The insulating resin composition according to claim 1, wherein a diameter of the inorganic filler is 0.008 to 10 μm.   The insulating resin composition comprises 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1- Benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1- Cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecyl-imidazolium trimellitate, 1-cyanoethyl-2-phenyl-imidazolium trimellitate, 2,4-diamino-6- (2′-methylimidazole) (1 '))-Ethyl-E S-triazine, 2,4-diamino-6- (2'-ethyl-4-methylimidazole- (1 '))-ethyl-es-triazine, 2,4-diamino-6- (2'-undecylimidazole) -(1 '))-ethyl-es-triazine, 2-pecyl-4,5-dihydroxymethylimidazole, 2-pecyl-4-methyl-5-hydroxymethyl, 2-pecyl-4-benzyl-5-hydroxymethyl Imidazole, 4,4'-methylene-bis- (2-ethyl-5-methylimidazole), 2-aminoethyl-2-methylimidazole, 1-cyanoethyl-2-phenyl-4,5-di (cyano-ethoxymethyl) ) One or more selected from imidazole, 1-dodecyl-2-methyl-3-benzylimidazolinium chloride and imidazole-containing polyamide The insulating resin composition according to claim 1, further comprising the above curing accelerator.   The insulating resin composition includes phenoxy resin, polyimide resin, polyamideimide (PAI) resin, polyetherimide (PEI) resin, polysulfone (PS) resin, polyethersulfone (PES) resin, polyphenylene ether (PPE) resin, The insulating resin composition according to claim 1, further comprising one or more thermoplastic resins selected from a polycarbonate (PC) resin, a polyether ether ketone (PEEK) resin, and a polyester resin.   The insulating film manufactured with the resin composition for insulation of Claim 1.   A prepreg produced by impregnating a base material with the insulating resin composition according to claim 1.   A printed circuit board comprising the insulating film according to claim 14.   A printed circuit board comprising the prepreg according to claim 15.

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