KR100887923B1 - Non-halogenated flame-retarding epoxy resin composition, resin coated copper foil produced with the same, and copper clad laminate - Google Patents

Abstract

Disclosed are a flame-retardant epoxy resin composition used to manufacture a multilayer printed circuit board, a resin coated copper foil and a copper foil laminated plate manufactured using the same. The non-halogen flame-retardant epoxy resin composition includes (i) a bisphenol A type epoxy, (ii) a biphenyl group-containing epoxy having self-extinguishing ability, (iii) a polyfunctional epoxy having three or more functional groups per molecule, and (iv) an aliphatic polyglycol. Epoxy resin containing rubber modified epoxy which made cylyl ether epoxy and rubber react; Novolak resin curing agents and imidazole compound curing accelerators; Polymers having functional groups crosslinkable with epoxy or having good compatibility with epoxy; And phosphorus-based flame retardants.

Printed Circuit Board, Resin Coated Copper Foil, Copper Clad Laminated Plate, Epoxy Resin, Novolak Resin, Bisphenol, Biphenol, Hardener, Phosphorus Flame Retardant

Description

Non-halogen flame-retardant epoxy resin composition, non-halogenated flame-retarding epoxy resin composition, resin coated copper foil produced with the same, and copper clad laminate}

The present invention relates to a non-halogen flame-retardant epoxy resin composition, and more particularly to a flame-retardant epoxy resin composition used to manufacture a multilayer printed circuit board, a resin coated copper foil and a copper foil laminated plate prepared using the same.

In general, in order to manufacture printed circuit boards used in electrical and electronic products, glass fibers, kraft paper, and nonwoven fabrics are impregnated with a thermosetting resin such as a phenol resin and an epoxy resin, and the resin is semi-cured (B After drying by -stage to make a prepreg, copper clad laminates (CCL) are manufactured by laminating copper foils on one or both surfaces thereof. In addition, when manufacturing three or more copper foil laminated boards classified into a multilayer printed circuit board, first, an inner layer substrate having conductors formed on the surfaces of both copper foil laminated plates is made, and an outer layer is formed on the surface by using prepreg and copper foil. Recently, microvia holes are formed between inner and outer copper clad laminates as circuit density increases and high integration such as pad sizes of printed circuit boards decreases and fine pitch. Is generalized. As a method of forming such a via hole, laser drilling processing or plasma processing is used. In this case, if the inorganic component such as glass fiber is contained as a reinforcement in the copper-clad laminate, it is not easy to process, so the insulation layer is often formed only of the resin component that does not contain the reinforcement, which is generally referred to as resin coated copper foil. Thus, by manufacturing a multilayer printed circuit board using a resin coated copper foil, via holes can be easily formed by using laser drill processing, and a more stable fine pitch circuit can be formed.

On the other hand, a printed circuit board composed of copper clad laminate, prepreg, and resin coated copper foil should have flame retardancy so as not to cause ignition in case of fire, and the standard for this flame retardancy follows UL standard and is required to be UL-94 V0 grade. Conventionally, tetrabromo bisphenol A (TBBA) containing a halogen-based flame retardant bromine (Br) is added to a resin composition constituting a copper clad laminate, a prepreg or a resin coated copper foil, or a TBBA-synthesized epoxy is used. come. However, due to the importance of environmental issues around the world, the use of hazardous materials such as lead and halogens is regulated in electrical and electronic products. In addition, when a printed circuit board containing a halogen material such as bromine is disposed of and incinerated, toxic carcinogens such as dioxin and dibenzofuran, and harmful harmful gases such as HBr are generated.

In order to solve the above problems, development of alternative flame retardants exhibiting the same flame retardant performance as existing halogen compounds has been made, and representatively, phosphorus flame retardants, nitrogen flame retardants, and inorganic flame retardants are known.

Phosphorus-based flame retardants decompose O and H from the epoxy resin by pyrolysis to produce phosphoric acid, metaphosphoric acid, and polymetaphosphate, which form an acid film on the surface of the resin or by dehydration when polymetaphosphate is produced. It forms a char film, and serves to block heat and oxygen (O ₂ ). However, phosphorus-based flame retardants generally have the disadvantage of lowering the water resistance and heat resistance of the resin. In addition, triphenyl phosphate (TPP) and cresyl diphenyl phosphate (CDP), which are monomeric phosphoric acid esters (phosphoric acid ester) in the form of additives, have a low molecular weight and thus have high volatility. It lowers physical properties such as solder blister and hygroscopicity. As reactive phosphorus flame retardants, Ajinomoto Fine Techno's resorcyl diphenyl phosphate (RDP) and Daepal Chemical's CR-757 are used. Is known to prevent degradation of the properties of the product (see US Pat. No. 6,214,455). Condensed phosphorus-based flame retardants are known as aromatic condensed phosphate (aromatic polyphosphate acid ester), and excellent hydrolysis resistance and endothermic stability, but has a disadvantage of lowering the Tg of the cured product.

Nitrogen-based flame retardants are divided into the case of using a nitrogen-containing melamine, methylguanamine, benzoguanamine (benzoguanamine) and the like and the nitrogen-containing reacted with a phenol curing agent. When a nitrogen-based flame retardant is added directly, the hygroscopicity resistance and lead heat resistance are lowered. Therefore, a nitrogen-modified phenol curing agent is prepared and used (see Japanese Patent No. 2000-53845). This method is a dehydration process under reduced pressure after the reaction. It is difficult and the effect of improving lead heat resistance is not great.

Inorganic flame retardants are not volatilized by heat, release a nonflammable gas such as H ₂ O, CO ₂ during decomposition, and endothermic reaction. Representative inorganic flame retardants include aluminum hydroxide (Al (OH) ₃ ), magnesium hydroxide (Mg (OH) ₂ ) and the like, in order to obtain a sufficient flame retardancy by using this alone, a large amount of flame retardant should be used. In addition, since these inorganic flame retardants are not dissolved in the resin system, the inorganic flame retardant can be used for the impregnation process of the copper foil laminated plate and the prepreg, but is difficult to use for the production of the resin coated copper foil. This is because surface irregularities and thickness variations are liable to occur without proper dispersion process, and the workability may be degraded during laser drilling. In addition, when the inorganic flame retardant is applied, it is hard and brittle, and the peel strength of the resin and the copper foil is greatly reduced, and the dielectric breakdown strength, the dielectric properties, and the electrical resistivity are reduced.

Accordingly, an object of the present invention is to provide an environmentally preferable non-halogen flame-retardant epoxy resin composition by not containing a halogen element.

Another object of the present invention is to provide a non-halogen-based flame retardant epoxy resin composition having good physical properties such as flame retardancy, heat resistance, peel strength, workability, storage stability, and a resin coated copper foil and a copper foil laminated plate manufactured using the same.

In order to achieve the above object, the present invention provides an epoxy resin of (i) bisphenol A form, (ii) a biphenyl group-containing epoxy having self-extinguishing ability, (iii) a multifunctional epoxy having a functional group of 3 or more per molecule, and (iv) an aliphatic poly Epoxy resin containing rubber modified epoxy which made glycidyl ether epoxy and rubber react; Novolak resin curing agents and imidazole compound curing accelerators; Polymers having a functional group crosslinkable with epoxy or excellent compatibility with epoxy; And it provides a non-halogen flame-retardant epoxy resin composition comprising a phosphorus-based flame retardant.

Here, the total content of the epoxy resin is 40 to 70% by weight relative to the total flame-retardant epoxy resin composition, the content of the novolak resin used as the curing agent is 15 to 40% by weight, the content of the imidazole compound curing accelerator 0.1 to 1 phr of 100 grams of epoxy resin, the content of the polymer having a crosslinkable functional group or excellent compatibility with the epoxy is 5 to 30% by weight, the content of the phosphorus-based flame retardant is 10 to 20% by weight desirable. In addition, the present invention provides a resin-coated copper foil coated with a resin layer on the surface of the copper foil using a resin composition and a copper-clad laminate prepared by laminating the resin-coated copper foil.

Hereinafter, the present invention will be described in more detail.

The epoxy resin included in the non-halogen flame-retardant epoxy resin composition according to the present invention is a bisphenol A-type epoxy (Br-free, equivalent 400 to 1000 g / eq), biphenyl group-containing epoxy (equivalent 260 to 300 g / eq) ), Rubber-modified epoxy (equivalent 170 to 350 g / eq, rubber) in which a polyfunctional epoxy (equivalent 180 to 250 g / eq) having a functional group of 3 or more molecules and a rubber reacted with an aliphatic polyglycidyl ether Content up to 50% by weight). The total content of the epoxy resin is 40 to 70% by weight relative to the total flame retardant epoxy resin composition (excluding the solvent), if the content of the epoxy resin is less than 40% by weight, the formed resin layer is vulnerable to electrical and mechanical deformation, When it exceeds 70% by weight, the flowability of the resin during the lamination process by the press is too high to form an appropriate insulating layer.

As the epoxy of the bisphenol A form, it is preferable to use a solid epoxy having an equivalent weight of 400 to 1000 g / eq, and such bisphenol A type epoxy removes the tack of the resin coating surface and imparts proper flowability. The bisphenol A-type epoxy may be prepared by, for example, reacting bisphenol A with epichlorohydrine (ECH). Specifically, the product name YD-011 of Kukdo Chemical may be used. The content of the epoxy of the bisphenol A form is preferably 10 to 50% by weight based on the total epoxy components, and if the content of the epoxy of the bisphenol A form is less than 10% by weight, the flowability is excessively reduced during the lamination process. There exists a problem that heat resistance and chemical resistance fall when it exceeds 50 weight%.

As the biphenyl group-containing epoxy, an equivalent weight of 260 to 300 g / eq is preferably used. Such biphenyl group-containing epoxy forms a foamed layer during combustion, and thus has a heat insulating effect and self-extinguishing property. Advantageously, the glass transition temperature (Tg) of the cured product is increased by the included biphenyl group, thereby improving the heat resistance of the resin. The biphenyl group-containing epoxy may be prepared by, for example, reacting 4,4′-dihydroxybiphenyl and epichlorohydrin, specifically, Nippon Kayaku's product names NC3000, NC3000-H, and the like. Can be used. The biphenyl group-containing epoxy content is preferably 10 to 50% by weight based on the total epoxy components. If the content of the biphenol-containing epoxy is less than 10% by weight, sufficient flame retardancy may not be obtained. If exceeded, a problem occurs that brittle resin is brittle.

The polyfunctional epoxy is an epoxy having three or more functional groups per molecule, and it is preferable to use an equivalent of 180 to 250 g / eq. Specifically, cresol novolak having three or more functional groups per molecule (o-cresol novolak) ) Epoxy (Kukdo Chemical Co., Ltd., YDCN500), tetraglycidyl ether of tetraphenylene ethane (Shell, Epon1031), which is a tetrafunctional epoxy, and the like can be used. The polyfunctional epoxy supplements the glass transition temperature and the soldering heat resistance of the cured product lowered by the use of a phosphorus-based flame retardant, and the content thereof is preferably 10 to 50% by weight based on the total epoxy component. If the content of the polyfunctional epoxy is less than 10% by weight, there is a problem that the heat resistance of the resin coated copper foil is lowered, and when the content of the polyfunctional epoxy exceeds 50% by weight, the dried resin is brittle and the flowability is excessively reduced during the lamination process. There is.

The resin-coated copper foil according to the present invention is coated on the copper foil in a state in which the resin is dissolved in a solvent such as methyl ethyl ketone, and then dried in a solvent to be used in a B-stage state. A piece of resin falls off. In order to improve such brittleness, the non-halogen-based flame retardant epoxy resin composition according to the present invention comprises a rubber such as carboxyl-terminated butadiene acrylonitrile rubber (CTBN) and an aliphatic polyglycidyl ether epoxy resin. The reacted rubber modified epoxy is included. The rubber-modified epoxy is preferably equivalent to 170 to 350g / eq, rubber content of 50% by weight or less, the content is preferably 5 to 20% by weight based on the total epoxy component. If the rubber-modified epoxy content is less than 5% by weight, the brittleness improvement effect is less. If the rubber content exceeds 20% by weight, heat resistance and hygroscopicity are deteriorated, and the surface of the resin coated copper foil in a dry state is tacky. have.

The curing agent included in the non-halogen flame-retardant epoxy resin composition according to the present invention uses a phenol (phenol) resin, and the reason is as follows. First, the dicyandiamide curing agent commonly used has a curing condition suitable for laminating resin coated copper foil, but for the dissolution thereof, a solvent such as dimethylformamide (4,4-dimethylformamide), which is a hazardous substance, is used. Should be used, there is a disadvantage that an additional process is required to prevent recrystallization of dicyandiamide. Secondly, when the phosphorus-based flame retardant is included as in the present invention, the phosphorus-based flame retardant interferes with the curing reaction of the curing agent including the amine group, and the curing reaction is not sufficiently achieved, and the adhesive strength, heat resistance and the like are significantly reduced. Phenolic resin used in the present invention, the higher the softening point (softening point), the higher the functional group gives a higher heat resistance to the resin. Phenolic resins that can be used in the present invention include phenol novolac, cresol novolacs, bisphenol A novolacs, multifunctional novolacs resins, or the like alone or mixed. The content is preferably 15 to 40% by weight based on the total flame retardant epoxy resin composition (excluding the solvent). When the amount of the curing agent is less than 15% by weight, the epoxy resin may not be cured sufficiently, resulting in deterioration of physical properties. When the amount of the curing agent is more than 40% by weight, the cured product may be too hard.

The non-halogen flame-retardant epoxy resin composition according to the present invention uses a curing accelerator together with a novolak resin curing agent in order to achieve sufficient degree of curing in the lamination conditions. As a curing accelerator for curing the composition according to the present invention at 170 to 180 ° C. within several hours, an imidazole compound may be used. For example, 1-methyl imidazole, 2- 2-methyl imidazole, 2-ethyl 4-methyl imidazole, 2-phenyl imidazole, 2-phenyl 4-methyl imidazole (2-phenyl 4-methyl imidazole) and their cyanoethylation derivatives, carboxylic acid derivatives, hydroxyl group derivatives and the like can be used alone or in combination. These curing accelerators are appropriately selected in consideration of the pot life and gelation time. The content of the curing accelerator used in the present invention is suitably 0.1 to 1 phr (parts per hundred resin (addition amount of curing accelerator to 100 g of epoxy resin)) with respect to 100 grams of epoxy resin. If the content of the curing accelerator is less than 0.1 phr, there is a fear that the resin is not sufficiently cured within a predetermined lamination process time, if it exceeds 1.0 phr there is a problem that the solder heat resistance is significantly lowered due to rapid curing. In addition, when the phenol novolak resin is used as the curing agent, the storage stability is lower than that of the latent curing agent such as dicyandiamide. Therefore, it is more preferable to apply the imidazole containing a hydroxymethyl group to improve the storage stability.

The non-halogen flame-retardant epoxy resin composition according to the present invention includes a polymer having a functional group capable of crosslinking with epoxy or having excellent compatibility with epoxy, which can be mixed and participate in a curing reaction. Unlike the process of manufacturing a copper clad laminated board or a prepreg by impregnating a reinforcing material with a resin liquid, in the resin composition for resin coating copper foil which concerns on this invention, addition of the polymer which functions as a reinforcing material is essential. The polymer, which acts as a reinforcing material, forms a resin layer with a certain thickness when coating the resin composition on the copper foil, imparts a certain range of fluidity during the lamination process, and cracks the resin layer during processing such as transporting and cutting the resin coated copper foil. It also serves to prevent the scattering of resin powder. The polymer included in the composition according to the present invention and serving as a reinforcing material includes polyvinyl acetal, polyvinyl butyral resin, and phenoxy having excellent compatibility with epoxy. (phenoxy) resin, carboxyl terminated butadiene acrylonitrile (CTBN), rubber modified reactive polyamide resin, mixtures thereof, and the like, and the content thereof is 5 to 50 phr or 100 flame retardant epoxy based on 100 grams of epoxy resin. 5 to 30% by weight relative to the resin composition (excluding solvent) is preferred. If the content of the polymer is less than 5 phr or 5% by weight, the reinforcing effect of maintaining the shape of the resin layer of the resin-coated copper foil is not sufficient. When the flowability of the resin becomes excessively high and exceeds 50 phr or 30% by weight, there is a problem that the heat resistance is lowered.

In addition, the non-halogen flame-retardant epoxy resin composition according to the present invention includes a phosphorus-based flame retardant for causing a synergistic effect of flame retardancy. As described above, since the addition of the phosphorus-based flame retardant causes deterioration of physical properties such as heat resistance and peeling strength, it is preferable to use the phosphorus-based flame retardant to the minimum as long as flame retardancy is ensured, and more preferably the entire flame-retardant epoxy resin composition (excluding solvent). 10 to 20% by weight is used. When the amount of the phosphorus-based flame retardant is less than 10% by weight, the flame retardancy may not be sufficient, and when the amount of the phosphorus-based flame retardant exceeds 20%, physical properties such as heat resistance and peel strength may be deteriorated. As the phosphorus flame retardant, a melting point such as an aromatic condensed phosphate ester is preferably used, which does not lower heat resistance. Specifically, the phosphorus flame retardant has a melting point of 95 ° C. or higher and a phosphorus (P) content of 8 to 12%, preferably 9.0%. As an aromatic polyphosphate acid ester, the product name PX-200 of Daepal Chemical, which is excellent in hydrolysis resistance and endothermic stability and does not have a large Tg decrease in cured product, can be used. The non-halogen flame-retardant epoxy resin composition according to the present invention may include, in addition to the above components, a suitable additive for wettability and surface leveling in copper foil coating.

Next, a method for producing a non-halogen flame retardant epoxy resin composition, a resin coated copper foil and a copper foil laminated plate according to the present invention will be described. First, the polymer serving as a reinforcing material is a solvent such as methyl ethyl ketone (MEK), 2-methoxyethanol, and propylene glycol monomethyl ether (PGME) at about 50 ° C. Dissolve under stirring. Next, the curing agent and the curing accelerator are dissolved in a solvent such as MEK, the epoxy resin component and the phosphorus-based flame retardant are added to the solution, then the reinforcing material polymer solution prepared above is mixed and stirred until completely dissolved. This composition is prepared so that the solids content is usually 30 to 50% by weight in order to maintain the viscosity of the coating is easy. The resin composition is applied to a rough surface of copper foil uniformly and dried by using a resin coating device such as an edge coater, a roll coater, a comma coater, and dried to obtain a semi-cured state ( The resin layer of B-stage) is formed on copper foil. The said copper foil has a thickness of 12-35 micrometers normally, and the thickness of the formed resin layer is 60-80 micrometers normally. The resin-coated copper foil thus prepared is laminated on both sides of the inner layer substrate having a predetermined circuit formed by hot press molding to produce a copper foil laminated plate. Lamination conditions are usually within 1 to 2 hours in the range of 0 to 25 kg / cm ² pressure, 50 to 200 ℃ temperature.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples.

[Example 1-4, Comparative Example 1-4] Preparation of non-halogen flame retardant epoxy resin composition

To prepare an epoxy resin composition having a composition shown in Table 1. In Table 1, each symbol means the following compound, and each numerical value means a weight part.

YD011: Bifunctional Bisphenol A Epoxy Resin (Solid Phase), Kukdo Chemical

YDCN500-90P: Oso-cresol novolac epoxy resin, Kukdo Chemical

NC3000-H: Biphenyl-containing epoxy resin, Nippon Gunpowder

KR207: Rubber modified epoxy, Kukdo Chemical                     

PX-200: Aromatic Condensed Phosphate Ester, Daepal Chemical

KS-5Z: Polyvinyl Butyral, Sekisui

PKHP200: phenoxy resin in powder form, phenoxy specialties

CTBN 1300X8, 1300X13: Rubber with carboxyl terminal, BF Goodrich

GP5833: Phenol Novolac Resin, Georgia Pacific

2P4MZ: 2-phenyl 4-methyl imidazole, Shikoku Chemical Industry

2PHZ: 2-phenyl 4,5-dihydroxymethyl imidazole, Shikoku Kasei Kogyo Co., Ltd.

2P4MHZ: 2-phenyl 4-methyl 5-hydroxymethyl imidazole, Shikoku Chemical Industry

Furtherance Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Epoxy YD011 20 10 20 20 20 60 20 20 YDCN500-90P 40 40 40 40 40 40 40 40 NC3000-H 40 50 40 40 40 40 40 KR207 5 5 5 5 5 5 Flame retardant PX-200 25 25 25 25 25 25 25 Polymer KS-5Z 10 10 10 10 10 10 10 10 PKHP-200 5 5 5 5 5 5 5 5 CTBN1300X13 3 Hardener GP5833 40 40 40 40 40 40 40 Curing accelerator 2E4MZ 0.1 0.1 0.1 0.1 0.1 2PHZ 0.2 2P4MHZ 0.2 0.2

For example, the production method of the epoxy resin composition will be described. First, the polymer which is difficult to dissolve is previously dissolved in a solvent. In a flask containing 50 g of methyl ethyl ketone (MEK) and 56 g of 2-methoxyethanol, 10 g of KS-5Z and 5 g of PKHP-200 were added, stirred and dissolved to prepare a 12.4% solution. At this time, the solution is accelerated by heating at about 50 ° C. with high speed stirring. 174 g of MEK was added to a 1000 ml flask, and 0.1 g of imidazole 2E4MZ and 40 g of phenol resin GP5833 were added and stirred to dissolve. 20 g of epoxy YD-011, 40 g of YDCN500-90P, 40 g of NC3000-H, and 5 g of KR207 were added to the solution, and 25 g of phosphorus flame retardant PX200 and 121 g of the polymer solution prepared above were added and stirred until completely dissolved. This resin composition is usually prepared in 30 to 50% solid content in order to maintain the viscosity of the coating, the above example was prepared in 40%. The gelation time of the resin composition was 120 to 200 seconds on a hot plate at 170 ° C. The compositions of Examples 2-5 and Comparative Examples 1-3 were also prepared in a similar manner to Example 1.

Manufacture of Resin Coated Copper Foil

The resin compositions of Examples and Comparative Examples were applied to a rough surface of copper foil using a resin coating device such as an edge coater, a roll coater, a comma coater, and dried at a uniform thickness, and dried. The resin layer of the semi-hardening state (B-stage) was formed on copper foil. The copper foil used the copper foil of 18 micrometers thick, and the thickness of the formed resin layer was adjusted to 80 micrometers.

Manufacture of Copper Clad Laminates

The resin coated copper foil was laminated by hot press molding on both sides of the FR-4 inner layer substrate on which a predetermined circuit was formed. Lamination conditions are within 1 to 2 hours in the range of pressure 0 ~ 25kg / cm ² , temperature 50 ~ 200 ℃.

Evaluation of Resin Coated Copper Foil and Copper Foil Laminated Plate

Table 2 shows the comprehensive evaluation results of the resin coated copper foil and the copper foil laminated plate manufactured using the compositions of the above Examples and Comparative Examples.

Item unit Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Flame retardant UL94 V-0 V-0 V-0 V-0 V-0 V-1 HB V-0 Heat resistance second 180 210 175 175 160 150 190 180 Peel strength kgf / cm 1.4 1.58 1.52 1.54 1.46 1.35 1.60 1.28 TMA Tg ℃ 125 136 124 125 120 117 130 124 Mandrell Φ (mm) 30 30 30 30 27.5 27.5 30 37.5 Storage stability Resin flowability Early

15th

30 days

45 days △ △

60 days △ △

△ Gel time change Early

15th △ △

30 days △ △

45 days ｘ ｘ △ △ 60 days ｘ ｘ △ △

In Table 2, the combustion test based on UL94 for the evaluation of flame retardancy. Samples of the combustion test were etched double-sided metal of a commercial copper clad laminate (0.5mm) and laminated a resin-coated copper foil by the above method to prepare a specimen having a length of 125mm and a width of 25mm and performed a vertical combustion test. A methane gas flame with a length of 20 mm is in contact with the sample twice for 10 seconds, and after the first 10 seconds of combustion, the extinguishing time is t1, the time after which the flame disappears after burning for the second 10 seconds is measured by t2 and the time of smoke remains as t3. If all of them meet the conditions of 10 seconds or less, t1 + t2 of 50 seconds or less, and t2 + t3 of 30 seconds or less, and the test material does not fall on the lower surface, the V0 grade is given. From Table 2, the addition of NC3000-H and PX-200 is essential to obtain the flame retardancy, it can be seen that exhibits flame retardancy of V0 grade especially when the content of phosphorus relative to the total weight in the above composition 10% or more.

The evaluation of lead heat resistance was performed by using a solder bath at 288 ° C to etch the copper-clad laminate laminated with the resin-coated copper foil according to the present invention to a size of 50 mm × 0 mm, and then swelling the copper foil according to IPC 2.4.13. The climb time was measured. It can be seen from Table 2 that the biphenyl-containing epoxy has increased lead heat resistance.

The peel strength was measured using UTM to measure the vertical peel strength, and the workability was evaluated by using the Gardener Mandrell Flexibility Tester. The resin-coated copper foil was cut into 2 cm width and 20 cm length to have different diameters. The diameter of the cylinder in which cracking of the resin layer occurs when contacting the metallic cylinder was recorded. As the flexibility of the formed resin layer decreases, cracking occurs in a large diameter cylinder. Good flexibility reduces damage during transport and operation of resin coated copper foil and increases workability. It can be seen from the Table 2 that the rubber is improved by adding a rubber-modified epoxy.

, 10~20% 감소를 △, 20% 이상 감소를 X로 나타내었다. 겔화시간은 170℃의 열판(hot plate)위에, 건조상태의 수지를 떼어내어 파우더(powder)형태로 만든 시료 100mg을 올려놓고 시간을 측정하여, 이쑤시개로 저어주며 들어올려 수지가 실처럼 늘어져 딸려오지 않을 때 까지의 시간을 측정한다. 위와 마찬가지로 시료를 25℃ 상온방치 후 15일 간격으로 측정하여, 처음 측정시의 10% 이내 무게 감소를

, 10~20% 무게 감소를 △, 20% 이상 무게 감소를 X로 나타낸다. 실시예 3-4의 결과와 같이, 범용으로 쓰이는 이미다졸인 2-에틸 4-메틸 이미다졸 보다 히드록시메틸기가 함유된 이미다졸을 사용한 경우 보관안정성이 우수하였다.
Storage stability was determined by evaluating resin flow and gelation time in resin coated copper foil. The resin flowability was measured by cutting the specimen into 10 cm × 0 cm size (w1) and measuring the weight after lamination (w2) to express the degree of resin escape during the lamination process in%. Samples were measured at 15 days intervals after standing at 25 ° C at room temperature, reducing within 10% of the initial measurement.

, 10-20% reduction, △, 20% or more reduction is represented by X. The gelation time was measured on a hot plate at 170 ° C by removing a dry resin, placing 100 mg of a sample in powder form, measuring the time, stirring it with a toothpick, and lifting the resin. Measure the time until not. As above, the samples were measured at 15 ° C intervals after 25 ° C room temperature, reducing the weight loss within 10% of the initial measurement.

, 10 to 20% weight loss, △, 20% or more weight loss. As in the result of Example 3-4, when the imidazole containing hydroxymethyl group was used rather than 2-ethyl 4-methyl imidazole which is a general-purpose imidazole, storage stability was excellent.

As described above, the resin composition and the resin coated copper foil according to the present invention have a flame retardancy of UL94-V0 without using a halogen-based flame retardant, and exhibit better heat resistance and peel strength than conventional resin coated copper foil. In addition, in terms of storage stability, which is a concern for using a phenol curing agent, it has a storage stability equivalent to that of the existing latent curing agent, and the process workability and flexibility are improved, so that a build-up multilayer board using these can be easily manufactured.

Claims (10)

(i) a bisphenol A type epoxy, (ii) a self-extinguishing biphenyl group-containing epoxy, (iii) a polyfunctional epoxy having at least 3 functional groups per molecule, and (iv) an aliphatic polyglycidyl ether epoxy reacted with rubber Epoxy resins including rubber-modified epoxy; Phenol resin curing agents and imidazole compound curing accelerators; A polymer having a functional group capable of crosslinking with epoxy or having good compatibility with epoxy, selected from the group consisting of polyvinyl acetal, polyvinyl butyral resin, phenoxy resin, rubber having carboxyl end, rubber modified polyamide resin, and mixtures thereof Polymers; And Non-halogen flame retardant epoxy resin composition comprising a phosphorus flame retardant. According to claim 1, wherein the total content of the epoxy resin is 40 to 70% by weight relative to the total flame-retardant epoxy resin composition, the content of the epoxy of the bisphenol A form is 10 to 50% by weight relative to the total epoxy component, The phenyl group-containing epoxy content is 10 to 50% by weight, the polyfunctional epoxy content is 10 to 50% by weight, and the content of the rubber-modified epoxy is 5 to 20% by weight of the non-halogen flame-retardant epoxy resin composition. According to claim 1, wherein the content of the phenol resin used as the curing agent is 15 to 40% by weight based on the total flame-retardant epoxy resin composition, the content of the imidazole compound curing accelerator is 0.1 to 1phr with respect to 100 grams of epoxy resin, The content of the polymer having a crosslinkable functional group or good compatibility with the epoxy is 5 to 30% by weight based on the total flame retardant epoxy resin composition, the content of the phosphorus-based flame retardant is 10 to 20% by weight based on the total flame-retardant epoxy resin composition A non-halogen flame-retardant epoxy resin composition which is%. According to claim 1, wherein the bisphenol A-type epoxy is a solid epoxy equivalent of 400 to 1000 g / eq, the biphenyl group-containing epoxy is equivalent to 260 to 300 g / eq, the polyfunctional epoxy is equivalent to 180 To 250g / eq, the rubber-modified epoxy is equivalent to 170 to 350g / eq, the rubber content of the non-halogen flame-retardant epoxy resin composition is 50% by weight or less. The non-halogen flame retardant epoxy resin composition according to claim 1, wherein the phenol resin curing agent is selected from the group consisting of phenol novolac, cresol novolac, bisphenol A novolac, polyfunctional novolac, and mixtures thereof. The method of claim 1, wherein the imidazole compound curing accelerator is 1-methylimidazole, 2-methylimidazole, 2-ethyl 4-methyl imidazole, 2-phenylimidazole, 2-phenyl4-methyl A non-halogen flame retardant epoxy resin composition selected from the group consisting of imidazole, cyanoethylation derivatives thereof, carboxylic acid derivatives, hydroxymethyl group derivatives and mixtures thereof. delete The non-halogen flame retardant epoxy resin composition of claim 1, wherein the phosphorus flame retardant is an aromatic condensed phosphate ester. The resin-coated copper foil which coated the resin layer on the surface of copper foil using the resin composition of any one of Claims 1-6 and 8. Copper-clad laminated board prepared by laminating the resin-coated copper foil according to claim 9.