KR101013074B1 - Epoxy resin composition and an adhesive film for a printed wiring boards prepared using the same - Google Patents

Abstract

The present invention provides an epoxy resin composition having high heat resistance, high peel strength, low dielectric constant, and low coefficient of thermal expansion, comprising an epoxy resin, a cyanate ester resin, a polyfunctional acid anhydride, and an inorganic filler, It is related with the adhesive film for printed wiring boards.

Epoxy resin, roughening agent, cyanate ester, polyfunctional acid anhydride, adhesive film, multilayer printed wiring board

Description

Epoxy resin composition and an adhesive film for a printed wiring boards prepared using the same}

The present invention relates to an epoxy resin composition and an adhesive film for a printed wiring board manufactured using the same. More specifically, the present invention provides an epoxy resin composition having high heat resistance, high peel strength, low dielectric constant, and low coefficient of thermal expansion, including epoxy resin, cyanate ester resin, polyfunctional acid anhydride, and inorganic filler. It is related with the adhesive film for printed wiring boards manufactured using.

In recent years, with the trend toward miniaturization and high performance of electronic devices, in the case of multi-layered PCBs, conductor wiring has been miniaturized in order to improve the mounting density of electronic components, and the thin and light reduction trend of electronic products has been in progress. For this reason, a microcircuit forming technique using a method by etching and a pattern method by plating has been proposed.

However, in the etching method, the thickness of the copper foil is not only increased, but the shape of the pattern is uneven, so that a fine circuit configuration is impossible in reality.

Therefore, in order to implement a fine pattern, a patterning method by plating is more preferable, and an insulating layer material for special build-up is used to apply to such a manufacturing method. Epoxy resins, phenol curing agents and the like are used as the insulating layer material of the multilayer printed wiring board, and these resins have the advantage of exhibiting excellent heat resistance and electrical insulation.

On the other hand, as a method of forming a high-density fine wiring on an insulating layer, a method of forming a conductor layer by electroless plating after roughening the surface of the insulating layer and a method of forming a conductor layer by combining electroless plating and electrolytic plating are known. have.

In this case, a roughening process is formed on the surface of the insulating layer by roughening treatment with an oxidizing agent such as an alkaline permanganic acid solution, followed by plating on the roughening surface to form a conductor layer. In the roughening process, there is a process of dissolving and removing smear generated in the process of forming a via hole in the insulating layer with a laser or the like. Problems may arise.

In addition, since the thermal expansion coefficient between copper wiring and an insulating layer is largely different in the multilayer printed wiring board which requires a high density of wiring, problems such as cracking occur, and therefore, it is required to reduce the thermal expansion coefficient of the insulating layer low.

Patent Application Publication No. 2002-87287 discloses a composition comprising an epoxy resin, a high heat resistance specific cyanate ester resin, a filler, a curing agent, and a metal catalyst in order to prepare an insulation composition having high heat resistance. However, in the case of such a composition, the heat resistance was improved, but the actual surface roughness was not formed, so that the peel strength with the conductor layer was not good, and there was a disadvantage of showing a high coefficient of thermal expansion.

An object of the present invention is to provide an epoxy resin composition having the characteristics of high heat resistance, high peel strength, low dielectric constant, and low coefficient of thermal expansion.

Another object of the present invention is to provide an adhesive film for a printed wiring board manufactured using an epoxy resin composition having characteristics of high heat resistance, high peel strength, low dielectric constant, and low thermal expansion coefficient.

It is still another object of the present invention to provide a method for manufacturing a multilayer printed wiring board using an epoxy resin composition having properties of high heat resistance, high peel strength, low dielectric constant, and low thermal expansion coefficient, and a multilayer printed wiring board manufactured therefrom. .

In order to achieve the above object, in the present invention (A) 10 to 20 parts by weight of a flame-retardant epoxy resin (A1), 5 to 15 parts by weight of a polyfunctional epoxy resin (A2), and rubber modified epoxy resin, phenoxy resin, and rubber 20 to 40 parts by weight of an epoxy resin including 5 to 15 parts by weight of at least one roughening agent (A3) selected from;

(B) 20 to 30 parts by weight of one or two or more cyanate ester resin mixtures selected from compounds having the following Chemical Formulas 1 to 3;

[Formula 1]

Wherein n is an integer of 1-5.

[Formula 2]

Wherein n is an integer of 1-5.

(3)

(C) 10 to 20 parts by weight of the multifunctional acid anhydride; And

(D) The epoxy resin composition which consists of 40-50 weight part of inorganic fillers is provided.

Since the epoxy resin composition according to the present invention has high heat resistance, high peel strength, low dielectric constant, and low coefficient of thermal expansion (CTE), it is used in the manufacture of an adhesive film for printed wiring boards or a multilayer printed wiring board.

In the present invention, an epoxy resin composition comprising a combination of an epoxy resin effective for forming an insulating layer of a multilayer printed wiring board, a roughening agent that is easy to form an anchor on the surface, and a polyfunctional acid anhydride curing agent, comprising: high heat resistance, high peel strength, low dielectric constant, And a resin composition having low thermal expansion coefficient characteristics.

The present inventors have continued to provide a resin composition having not only high heat resistance but also high peel strength, low dielectric constant, and low thermal expansion coefficient. As a result, the present inventors have studied flame retardant epoxy resin, polyfunctional epoxy resin, and rubber modified epoxy resin. The present invention has been completed by discovering that the epoxy resin composition comprising the epoxy resin mixture, the specific cyanate ester mixture, the polyfunctional acid anhydride, and the inorganic filler is composed of excellent heat resistance and coordination characteristics while maintaining low thermal expansion rate. .

The first aspect of the present invention is (A) 20 to 40 parts by weight of an epoxy resin consisting of 10 to 20 parts of a flame retardant epoxy resin, 5 to 15 parts of a polyfunctional epoxy resin and 5 to 15 parts of a rubber modified epoxy resin (B) Cyanate ester resin 20-30 weight part (C) 10-20 weight part of polyfunctional acid anhydrides, and (D) It is related with the epoxy resin composition containing 40-50 weight part of inorganic fillers.

The second aspect of the present invention relates to an adhesive film for a printed wiring board formed by applying the epoxy resin composition according to the present invention on a support base film.

The 3rd surface of this invention is the process of (1) forming the epoxy resin composition which concerns on this invention as a resin layer on the copper foil layer material in which the inner layer circuit was formed, and thermosetting; (2) forming a roughened surface of the uneven surface by the roughening treatment by an aqueous solution of an oxidizing agent on the surface of the resin layer; And (3) a method of manufacturing a multilayer printed wiring board according to the step of forming a conductor layer on the roughened surface, and a multilayer printed wiring board manufactured therefrom.

Hereinafter, the components of the epoxy resin composition according to the present invention will be described in more detail.

(A) epoxy resin

The resin composition according to the present invention comprises 20 to 40 parts by weight of an epoxy resin composed of 10 to 20 parts by weight of a flame retardant epoxy resin, 5 to 15 parts by weight of a polyfunctional epoxy resin, and 5 to 15 parts by weight of a roughening agent.

In order to improve the flame retardant property of the insulating layer, the compounded flame retardant epoxy resin (A1) is used. The flame-retardant epoxy resin is not particularly limited as long as it is an epoxy resin having flame retardancy, and among the commercially available flame-retardant epoxy resins, FX-305 of Dongdo Chemical Co., Ltd., KDP-540, KDP-550, KDP-555 of Kukdo Chemical Co., Ltd. Etc. These flame-retardant epoxy resins are used alone or in combination of two or more, and it is preferable to use 10 to 20 parts by weight in the resin composition. If the content of the flame-retardant epoxy resin is less than 10 parts by weight, the flame retardancy is insufficient, and if it exceeds 20 parts by weight, the heat resistance is lowered.

The polyfunctional epoxy resin (A2) is bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, biphenyl type epoxy resin, naphthalene type epoxy resin, phenol novolak type epoxy resin, cresol novolac type epoxy resin The at least one epoxy compound selected from the above is not particularly limited, but representative examples thereof include 1, 1, 1-tris hydroxyphenyl ethane glycidyl ether, sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, diglycerol poly Examples include glycidyl ether, triglycidyl tris (2-hydroxyethyl) isocyanurate, and glycerol polyglycidyl ether, and KDT-4400, YH-300, YH available from Kukdo Chemical Co., Ltd. -325 and the like. A polyfunctional epoxy resin is used individually or in combination of 2 or more types, in 5-15 weight part. If the content is less than 5 parts by weight, the heat resistance is insufficient. If the content is more than 15 parts by weight, the flame retardancy is lowered.

The roughening agent (A3) according to the present invention is solubilized or decomposed in an aqueous solution of an oxidizing agent to form an anchor of fine concavo-convex on the surface of the resin composition, thereby improving the peel strength with the conductor layer after plating. At least one roughening agent selected from municipal resins, and rubbers. Specific examples include YP-55, YP-70, ZX-1356-2 of Dongdo Chemical, EFR-001, YPS-007, 1256, 4250, 4275, 1255, YX8100, YX6954, Nagase Chemical Co., Ltd. R-45 EPT, Daishell Chemical Co., Ltd. PB3600, Japan JEON Co., Ltd. NBR, CTBN, PB. It is preferable that 5-15 weight part of such roughening agents are used in a resin composition. Harmonicity is inadequate when it is less than 5 weight part, and when it exceeds 15 weight part, electrical characteristics and heat resistance will fall.

(B) cyanate ester resin

The resin composition according to the present invention comprises 20 to 30 parts by weight of one or two or more cyanate ester resin mixtures selected from compounds having the following Chemical Formulas 1 to 3 to improve heat resistance and dielectric constant:

[Formula 1]

Wherein n is an integer of 1-5.

[Formula 2]

Wherein n is an integer of 1-5.

(3)

The cyanate ester resin may be used alone or as a mixture of two or more resins having excellent heat resistance and thermal properties. Specific examples include PT-15, PT-30, PT-30S, PT-60, PT-60S, CT-90, BA-230S, etc. manufactured by Lonza, Switzerland.

It is preferable to use 20-30 weight part of cyanate ester resin based on the total weight of a resin composition. If the cyanate ester-based resin is more than 30 parts by weight exothermic reaction occurs rapidly it is difficult to control the reaction, economical during the production of the product is added when less than 20 parts by weight, does not show the intended effect.

(C) polyfunctional acid anhydrides

The resin composition according to the present invention contains 10 to 20 parts by weight of a polyfunctional acid anhydride for curing the epoxy resin. If the content of the polyfunctional acid anhydride is less than 10 parts by weight, the heat resistance is lowered. If it is more than 20 parts by weight, unreacted active hydrogen groups remain and insulation is reduced. When the polyfunctional acid anhydride is used, the effect of improving heat resistance, electrical insulation, mechanical strength, and the like is obtained.

As a polyfunctional acid anhydride used as a hardening | curing agent, pyrometallic anhydride, a benzophenone tetracarboxylic anhydride, ethylene glycol bis trimetalic anhydride, a glycerol tris trimetallic anhydride, maleic methylcyclohexene tetracarboxylic anhydride, etc. The polyfunctional acid anhydride may be used alone or in combination of two or more, but is not limited thereto. Specific examples include pythathalic dianhydride (PMDA), benzophenon tetracarboxylic dianhdride (BTDA), ethylene glycol bis-trimethalic dianhydride (TMEG), glycerin tris-trimethalic dianhydride (TMTA), and MCTC (5- (2,5 dioxo tetrahydropryle) -3-methyl -3-cyclohexene-1,2-dicarboxylic anhydride), TDA ((2,5-dioxotetrahydrofuran-3-yl) -1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic anhydride), zefen epoxy resin (Note ) YH-308 and the like.

(D) inorganic filler

An inorganic filler is included to lower the thermal expansion rate of the resin composition according to the present invention.

The inorganic filler lowers the coefficient of thermal expansion, and the content ratio to the resin composition depends on the properties required in consideration of the use of the resin composition and the like, but is preferably 40 to 50 parts by weight in the resin composition. If it is less than 40 weight part, a thermal expansion rate will become high and when it is 50 weight part or more, there exists a tendency for peeling strength to fall. Most preferably, the content of the inorganic filler is at least 40% by weight based on the solids of the entire resin composition.

Examples of inorganic fillers include silica, alumina, barium sulfate, talc, mud, mica powder, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum borate, barium titanate, calcium titanate, magnesium titanate, and titanate Bismuth, titanium oxide, barium zirconate, calcium zirconate and the like are used alone or in combination of two or more thereof. Especially preferred is silica. Among the commercially available silicas, preferred products include SFP-20M, SFP-30M (from DENKA) and SO-E5 (Admatechs).

When the inorganic filler has an average particle diameter of more than 5 µm, it is difficult to stably form a fine pattern when forming a circuit pattern in the conductor layer, so that the average particle diameter is preferably 5 µm or less.

Moreover, in order to improve moisture resistance, it is preferable that the inorganic filler is surface-treated with surface treating agents, such as a silane coupling agent.

In addition to the above essential components (A) to (D), the resin composition of the present invention may be blended with a thermosetting resin or a conventional additive in an appropriate amount in a range not impairing the effects of the present invention. As a thermosetting resin, a block isocyanate resin, xylene resin, a radical generator, a polymeric resin, etc. are mentioned, for example. As an additive, For example, organic fillers, such as a silicone powder, nylon powder, and a fluorine powder, thickeners, such as orbene and benton, a silicone type, a fluorine type, a polymeric antifoamer or a leveling agent, an imidazole type, a zizor type | system | group, a triazole type, Additives generally used in the art, such as adhesive imparting agents, such as a silane coupling agent, are mentioned.

The resin composition according to the present invention comprises the epoxy resin (A) in a conventional organic solvent such as ketones, aromatic hydrocarbons, glycol ethers, esters, alcohols, aliphatic hydrocarbons, or petroleum solvents such as methyl ethyl ketone. After heating and dissolving with stirring and cooling to room temperature, an inorganic filler (D) component was added to the dissolved mixture, followed by sufficient stirring, followed by addition of a cyanate ester resin (B) component and a polyfunctional acid anhydride (C) component. Manufacture.

Preparation of Adhesive Film

The resin composition according to the present invention may be dissolved in an organic solvent, and then coated on a support base film to dry the solvent by hot air to prepare an adhesive film. The thickness of an epoxy resin composition layer is formed in the range of 10-100 micrometers in the support base film whose thickness is 10-100 micrometers. At this time, when the thickness of the epoxy resin composition layer is too thin, a good peel value cannot be obtained, and when too thick, there is a difficulty in forming a fine circuit. The residual solvent amount of the resin layer after drying is preferably 5% by weight or less based on the total weight of the resin composition.

Polyolefin, such as polyethylene, polypropylene, and polyvinyl chloride, polyester, such as polyethylene terephthalate, a polycarbonate, polyimide, etc. are used as a support base film.

Organic solvents include ketones such as acetone, methyl ethyl ketone and cyclohexanone, ethyl acetate, butyl acetate, cellosolve acetate, aromatic hydrocarbons such as propylene glycol monomethyl ether acetate, toluene and xylene, dimethyl formamide, dimethyl acetamide, N-methyl pyrrolidone etc. can be used individually or in combination of 2 or more types.

Multilayer printing Wiring board  Produce

The adhesive film of the present invention is laminated on the processed circuit board while pressing and heating after removing the protective film. The lamination step is a step of laminating under reduced pressure at a compression temperature of 90 to 120 ° C. and a compression pressure of 1 to 5 kgf / cm 2. Thereafter, the support film is peeled off and then heat cured. Heat-hardening is made in the range of 20 minutes-180 minutes under 150-220 degreeC, Preferably it is made for 30 minutes-120 minutes under 160-200 degreeC.

After heat-hardening, a perforation is performed to the insulating layer formed on a circuit board, and a via hole and a through hole are formed. Although punching can be performed by well-known methods, such as a drill, a laser, and a plasma, for example, drilling by a laser is the most common method.

Then, the surface of the insulating layer is treated with an oxidizing agent to perform a roughening treatment. Examples of the oxidizing agent include salts of permanganate (such as potassium permanganate, sodium permanganate), dichromate, ozone, hydrogen peroxide / sulfuric acid, acetic acid, and the like. It is preferable to perform a roughening process using alkaline permanganate solution (for example, potassium permanganate, the sodium hydroxide solution of sodium permanganate).

Thereafter, the conductor layer is formed on the surface of the resin composition layer on which the uneven anchor is formed by the roughening treatment by electroless plating and electrolytic plating. After forming the conductor layer, the annealing treatment at 150 to 200 ° C. for 20 to 90 minutes may further improve the peel strength of the conductor layer.

Although an Example demonstrates this invention concretely below, this invention is not limited to this.

Example

<Examples 1-4>

According to the composition of Examples 1-4 of Table 1, each component and hardening accelerator were mixed uniformly in the methyl ethyl ketone solvent, and the resin varnish was produced. The resin varnish was applied on a polyethylene terephthalate film having a thickness of 38 µm with a coater, and after drying, the thickness of the epoxy resin was 40 µm to obtain an adhesive film. The circuit board was laminated with a vacuum laminator. After curing at 180 ° C. for 60 minutes, a via hole was formed with a laser, roughened with potassium permanganate, and a conductor layer was formed by electroless plating and electroplating. Annealing treatment was performed at 190 ° C. for 60 minutes to stabilize the adhesion strength of the conductors.

<Comparative Examples 1 to 3>

It carried out according to Examples 1-4 except having used the resin composition of the composition of the comparative examples 1-3 of Table 1.

(Unit: parts by weight)                 Furtherance Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Comparative Example 3 (A) component             KDP-540 (A1)    15    16    10    10              FX-305 (A2)    7.5     5    10    11             YX-8800 (A2)    30     Bisphenol A type epoxy resin (A2)    62    12  Tetrafunctional Type Epoxy Resin (A2)     5    12            YL6954BH30 (A2)    15              R-45 EPT (A3)    7.5    12                YP-70 (A3)     7    11 (B) component                 PT-15    10                 PT-30    10    12    25                 PT-30S    10    25                 PT-60    10    10                 PT-60S    10                 CT-90    10                 BA-230S    12                 BA-200    10                 BA-230S75    30 (C) component                 PMDA    10                 BTDA    12                 TMEG    5                 TMTA    5                 MCTC     5                 YH-308     5                 NMA    20                 DICY     9 (D) component                 Silica    42    40    40    43    25     0     6

<Remarks>

KDP-540: Kukdo Chemical Co., Ltd.

FX-305: Dongdo Chemical Co., Ltd., polyfunctional epoxy resin

YX-8800: Zefenepoxy Resin Co., Ltd., anthracene type epoxy resin

YL6954BH30: Zefenepoxy Resin Co., Ltd., biphenyl type phenoxy resin solution

R-45 EPT: Nagase Chemical Industry Co., Ltd., rubber modified epoxy resin

YP-70: Dongdo Chemical Co., Ltd., phenoxy resin

PT-15: Lonza, Cyanate Ester Resin

PT-30: Lonza, Cyanate Ester Resin

PT-30S: Lonza, Cyanate Ester Resin

PT-60: Lonza, Cyanate Ester Resin

PT-60S: Lonza, Cyanate Ester Resins

CT-90: Lonza, Cyanate Ester Resins

BA-230S: Lonza, Cyanate Ester Resins

BA-230S75: Lonza, Cyanate Ester Resins

PMDA: Mitsubishi Gas Chemical Co., Ltd., pyrometallic anhydride

BTDA: Daicel Chemical Co., Ltd., Benzophenone tetracarboxylic anhydride

TMEG: Nippon Ewha Co., Ltd., ethylene glycol bistrimetallic anhydride

TMTA: Nippon Ewha Co., Ltd., Glycerol Tris Trimetallic Anhydride

MCTC: Nippon Chemical Ink Industry Co., Ltd., Maleic methylcyclohexene tetracarboxylic anhydride

YH-308: Zefen Epoxy Resin Co., Ltd.

NMA: Kukdo Chemical Co., Ltd.

DICY: Kukdo Chemical Co., Ltd., Dicyandiamide

Silica: DENKA, SFP-20M

The glass transition temperature, thermal expansion coefficient (CTE), insulation properties, peel strength, and flame retardance of each specimen obtained in Examples 1 to 4 and Comparative Examples 1 to 3 were measured, and the results are shown in Table 2.

 Example 1  Example 2  Example 3  Example 4  Comparative Example 1  Comparative Example 2  Comparative Example 3       Tg (占 폚)    198    187    190    205    152    185    190      CTE (ppm)     37     39     36     35     35     95     83      Insulation properties     o     o     o     o     o     o     o      Peel strength     7     8     6     6     7     4     3      Flammability    V-0    V-0    V-0    V-0    V-1    V-0    V-0

<Measurement method of physical property>

Tg: glass transition temperature (TMA method)

CTE: coefficient of thermal expansion (TMA method)

Insulation property: Insulation resistance value after PCT (121 ℃, 100%, 2atm)

           ○ = 1000 Hz or more × = 1000 Hz

Peel Strength: JIS-C-6481 (N / cm)

Flame Retardant: UL94V-0

As can be seen in Table 2, the specimen prepared using the epoxy resin composition according to the present invention of Examples 1 to 4 has no problem in heat resistance and insulation properties, exhibits good peel value and high glass transition temperature, and has a low coefficient of thermal expansion. It can be seen that. However, the specimen of Comparative Example 1 having no composition according to the present invention had good peel strength or thermal expansion rate but insufficient heat resistance and flame retardancy, and the specimens of Comparative Examples 2-3 had good thermal resistance but insufficient peel strength and high thermal expansion rate. There was a problem.

Claims (7)

(A) Epoxy comprising 10 to 20 parts by weight of a flame retardant epoxy resin, 5 to 15 parts by weight of a polyfunctional epoxy resin, and 5 to 15 parts by weight of at least one roughening agent selected from rubber-modified epoxy resins, phenoxy resins, and rubbers. 20 to 40 parts by weight of resin; (B) 20 to 30 parts by weight of one or two or more cyanate ester resin mixtures selected from compounds having the following Chemical Formulas 1 to 3; [Formula 1]

Wherein n is an integer of 1-5. [Formula 2]

Wherein n is an integer of 1-5. (3)

(C) 10 to 20 parts by weight of the multifunctional acid anhydride; And (D) The epoxy resin composition containing 40-50 weight part of inorganic fillers. 2. The polyfunctional acid anhydride according to claim 1, wherein the polyfunctional acid anhydride is pyrometallic anhydride, benzophenone tetracarboxylic anhydride, ethylene glycol bistrimetallic anhydride, glycerol tris trimetallic anhydride, maleic methylcyclohexene tetracarboxylic anhydride Epoxy resin composition, characterized in that at least one selected from the group containing. The method of claim 1, wherein the inorganic filler is silica, alumina, barium sulfate, talc, mud, mica powder, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum borate, barium titanate, calcium titanate And an epoxy resin composition having a diameter of 5 µm or less as one or more fillers selected from the group consisting of magnesium titanate, bismuth titanate, titanium oxide, barium zirconate, and calcium zirconate. The epoxy resin composition according to claim 3, wherein the content of the inorganic filler is 40% by weight or more based on the solids content of the resin composition. The adhesive film for printed wiring boards formed by apply | coating the epoxy resin composition of any one of Claims 1-4 on a support base film. The step of thermosetting the epoxy resin composition of any one of Claims 1-4 as a resin layer on the copper foil layer material in which the inner layer circuit was formed; Forming a roughened surface on the surface of the resin layer by a roughening agent treatment with an aqueous solution of an oxidizing agent; And Forming a conductor layer on the roughened surface: Method for producing a multilayer printed wiring board comprising a. The multilayer printed wiring board obtained by hardening | curing the epoxy resin composition of any one of Claims 1-4.