JPH10298406A - Epoxy resin composition for metal-foil-clad laminate and prepreg for metal-foil-clad laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a composition which can give prepregs being useful for obtaining metal-foil-clad laminates excellent in a glass transition temperature and being scarcely forms a broken resin powder during handling, etc., by mixing an epoxy resin with an amine curing agent, a cure accelerator and a linear block polymer having specified structural units. SOLUTION: This composition comprises an epoxy resin, desirably containing 50-100 pts.wt. tetrabromobisphenol A epoxy resin per 100 pts.wt. total epoxy resin, an aminic curing agent desirably containing dicyandiamide, a cure accelerator (e.g. 2-ethyl-4-methylimidazole) and a linear block polymer having structural units represented by formula I (wherein R is an alkyl) and formulas II and III and desirably having a Vicat softening point of 55-100 deg.C. It is desirable that the linear block polymer used in an amount of 1-8 pts.wt. per 100 pts.wt. total epoxy resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an epoxy resin composition and a prepreg used for manufacturing a metal foil-clad laminate used for electric / electronic equipment and the like.

[0002]

2. Description of the Related Art For example, a metal foil-clad laminate used for electric and electronic equipment is impregnated with a thermosetting resin varnish such as an epoxy resin composition on a substrate such as a glass cloth and then heated to a half. A prepreg is manufactured by curing, a required number of prepregs are stacked, and a metal foil such as a copper foil is arranged and laminated on one or both sides of the prepreg, and heated and pressed to perform molding. In addition, the multilayer metal foil-clad laminate is formed by etching the metal foil on the surface of the metal foil-clad laminate obtained by the above method to form a conductor circuit, and then, on the front and back of the laminate on which the conductor circuit is formed. It is manufactured by stacking a required number of the same prepregs as described above, arranging and laminating metal foils on one or both sides thereof, and performing molding by heating and pressing.

When a prepreg is used when manufacturing a metal foil-clad laminate, the resin in the prepreg lowers in viscosity as soon as it is heated, causing the resin to flow. . for that reason,
When handling during lamination, it is easy to handle because it is solid,
In addition, during molding by heating and pressurizing, it has a certain degree of fluidity, so that bubbles are unlikely to remain in the resulting metal foil-clad laminate, and even if there is some variation in the amount of resin, it has a substantially uniform thickness. It is generally used because it has a feature that a metal foil-clad laminate can be obtained.

When an epoxy resin composition is used as the resin varnish, an amine-based curing agent such as dicyandiamide is used as a curing agent in order to secure the glass transition temperature of the metal foil-clad laminate and the storage stability of the prepreg. It is generally done.

[0005] The resin in the prepreg is generally brittle because it is in a semi-cured state called a B stage, and the resin is broken when a large force is applied to the resin during handling or cutting into a predetermined size. The broken powder of the resin sometimes adhered to the end face or surface of the prepreg.

When a metal foil-clad laminate is to be manufactured using a prepreg to which the broken powder of the resin adheres, the broken powder of the resin floats at the time of lamination and adheres to the surface of the metal foil. In some cases, a fine cured product of a resin is formed on the metal foil surface of the resulting metal foil-clad laminate. When a circuit is formed by etching the metal foil of the metal foil-clad laminate on which the cured product of the resin is formed, the portion where the cured product of the resin is formed remains without being etched, and the circuit is formed. There is a problem that the circuit may be short-circuited and the yield of the circuit is low.

Therefore, without impairing the characteristic that a metal foil-clad laminate excellent in glass transition temperature and the like, which is a feature of a prepreg using an amine-based curing agent, is obtained.
There is a need for a prepreg for a metal foil-clad laminate that is less likely to generate broken powder of resin in handling and an epoxy resin composition for a metal foil-clad laminate from which the prepreg for the metal foil-clad laminate can be obtained.

[0008]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a metal foil-clad laminate containing an epoxy resin and an amine-based curing agent. An epoxy resin composition, a metal foil-clad laminate having an excellent glass transition temperature can be obtained, and a prepreg that does not easily generate broken resin powder during handling or the like can be obtained. It is to provide a resin composition.

Another object of the present invention is to provide a prepreg for a metal-foil-clad laminate in which a metal-foil-clad laminate having an excellent glass transition temperature can be obtained, and in which, for example, resin broken powder is less likely to be generated in handling and the like.

[0010]

The epoxy resin composition for a metal foil-clad laminate according to claim 1 of the present invention comprises an epoxy resin, an amine-based curing agent, a curing accelerator, and a compound represented by the following formula (a): And a linear block polymer having structural units represented by formulas (b) and (c).

[0011]

Embedded image

[0012] The epoxy resin composition for a metal foil-clad laminate according to claim 2 of the present invention is the epoxy resin composition for a metal foil-clad laminate according to claim 1, wherein
It is characterized by containing 1 to 8 parts by weight of a linear block polymer with respect to 00 parts by weight.

[0013] The epoxy resin composition for a metal foil-clad laminate according to claim 3 of the present invention is the epoxy resin composition for a metal foil-clad laminate according to claim 1 or 2, wherein , Vicat softening point is 55-1
It is characterized by containing a linear block polymer at 00 ° C.

[0014] The epoxy resin composition for a metal foil-clad laminate according to claim 4 of the present invention is the epoxy resin composition for a metal foil-clad laminate according to any one of claims 1 to 3, wherein It is characterized by containing dicyandiamide as a curing agent.

The epoxy resin composition for a metal foil-clad laminate according to claim 5 of the present invention is the epoxy resin composition for a metal foil-clad laminate according to any one of claims 1 to 4, wherein It is characterized by containing 50 to 100 parts by weight of a tetrabromobisphenol A type epoxy resin with respect to 100 parts by weight of the resin.

A prepreg for a metal foil-clad laminate according to claim 6 of the present invention is obtained by impregnating a base material with the epoxy resin composition for a metal foil-clad laminate according to any one of claims 1 to 5. Later, it becomes solidified.

A prepreg for a metal foil-clad laminate according to claim 7 of the present invention is characterized in that, in the prepreg for a metal foil-clad laminate according to claim 6, the base material is a glass cloth.

According to the present invention, since the above-mentioned linear block polymer is contained in the epoxy resin composition, the flexibility of the semi-cured resin contained in the obtained prepreg is increased, and the impact resistance is improved. Even when a large force is applied to the resin during handling, cutting into a predetermined size, or the like, it is considered that the resin is unlikely to be broken. Further, since the linear block polymer is a compound that does not easily lower the glass transition temperature of the cured product of the epoxy resin composition, the glass transition temperature, which is a feature of the prepreg using an amine-based curing agent, is excellent. It is considered that the property of obtaining a metal foil-clad laminate is hardly impaired, and a metal foil-clad laminate having an excellent glass transition temperature can be obtained.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The epoxy resin composition for a metal foil-clad laminate according to any one of claims 1 to 5 of the present invention comprises at least an epoxy resin, an amine-based curing agent, a curing accelerator, (A), a linear block polymer having structural units represented by formulas (b) and (c).

The epoxy resin used in the present invention includes:
There is no particular limitation as long as the epoxy resin has two or more epoxy groups in the molecule. Examples thereof include bisphenol A epoxy resin, bisphenol F epoxy resin, phenol novolak epoxy resin, bisphenol A novolak epoxy resin, and cresol. Novolak-type epoxy resins, diaminodiphenylmethane-type epoxy resins, and epoxy resins in which some of the hydrogen atoms in these epoxy resin structures are halogenated to make them flame-retardant alone, modified products, and mixtures thereof.

The upper limit of the number of epoxy groups in the epoxy resin is too large, the viscosity of the epoxy resin composition becomes high, and the impregnation property of the base material is lowered. preferable. Note that an epoxy resin having one epoxy group in the molecule can be used in combination.

When a plurality of types of epoxy resins are used in combination,
It has two or more epoxy groups in the molecule and an epoxy equivalent of 200 to 10 parts by weight based on 100 parts by weight of the total epoxy resin.
It is preferable to contain 50 parts by weight or more of the epoxy resin No. 00. Epoxy resins having an epoxy equivalent of 200 to 1000 have an appropriate melt viscosity and are characterized in that rapid three-dimensional crosslinking does not proceed during the curing reaction. It is preferable because the gelation time of the resin in the resin can be easily controlled.

The epoxy resin is bisphenol A
Epoxy resin, tetrabromobisphenol A type epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin, bisphenol A novolak type epoxy resin It is preferable because a metal foil-clad laminate having excellent electrical and physical properties and a balance between the two can be obtained. When using a tetrabromobisphenol A type epoxy resin,
Further, a metal foil-clad laminate excellent in flame retardancy is obtained, which is preferable.

The amine-based curing agent used in the present invention is not particularly limited as long as it is an amine-based compound which is cured by reacting with an epoxy resin. For example, dicyandiamide, aliphatic polyamide, aromatic diamine and the like. Derivatives and the like can be exemplified, and these may be used alone or in combination of two or more. The amount of the amine-based curing agent is 1
It is desirable to add 0.1 to 2 equivalents to the epoxy equivalent of the epoxy resin. When the amount is less than 0.1 equivalent or more than 2 equivalents, the heat resistance of the obtained metal foil-clad laminate may decrease. When dicyandiamide is contained as the amine-based curing agent, the storage stability of the obtained prepreg and the heat resistance of the obtained metal foil-clad laminate are particularly excellent and are preferable.

As long as the object of the present invention is not impaired, phenolic curing agents such as bisphenol A, bisphenol F, phenol novolak, cresol novolak, diaminomaleonitrile,
A hydrazide compound, an acid anhydride or the like can be used in combination.

The curing accelerator used in the present invention is not particularly limited, but includes 2-methylimidazole,
Imidazoles such as 2-ethyl-4-methylimidazole and 2-phenylimidazole; tertiary amines such as 1,8-diaza-bicyclo [5.4.0] undecene-7, triethylenediamine and benzyldimethylamine; tributyl Examples thereof include organic phosphines such as phosphine and triphenylphosphine, and tetraphenylboron salts such as tetraphenylphosphonium tetraphenylborate and triphenylphosphine tetraphenylborate. These may be used alone or in combination of two or more. Is also good.
Usually, the content of the curing accelerator is preferably about 1 part by weight or less based on 100 parts by weight of the solid content of the epoxy resin composition.

The linear block polymer used in the present invention is a compound having the structural units represented by the above formulas (a), (b) and (c). , And is represented by the following equation (d). Note that in equation (d),
R represents an alkyl group, and x, y, and z represent a polymerization ratio.
Further, the blocks of the structural units represented by the above formulas (a), (b) and (c) are not limited to one block, respectively, and a plurality of blocks may be provided.

[0028]

Embedded image

The epoxy resin composition preferably contains the linear block polymer in an amount of 1 to 8 parts by weight based on 100 parts by weight of the epoxy resin in total. If the amount is less than 1 part by weight, the effect of increasing the flexibility of the resin contained in the prepreg and improving the impact resistance is reduced, so that broken powder of the resin may be generated during handling or the like. If the amount exceeds 8 parts by weight, the glass transition temperature of the resulting metal foil-clad laminate may be low.

The linear block polymer preferably has a Vicat softening point of 55 to 100 ° C. When the temperature is lower than 55 ° C. or higher than 100 ° C., broken resin powder may be generated from the obtained prepreg, or the glass transition temperature of the obtained metal foil-clad laminate may be low.

The epoxy resin composition of the present invention may contain a solvent, an inorganic filler and the like, if necessary. The solvent that can be used is not particularly limited as long as it is a solvent that can obtain a uniform solution of the resin composition.
Examples thereof include ketones such as acetone and methyl ethyl ketone, ethers such as ethylene glycol monomethyl ether and ethylene glycol butyl ether, aromatic hydrocarbons such as benzene and toluene, and methoxypropanol. These may be used alone or in combination of two or more.

After the base material is impregnated with the epoxy resin composition, it is solidified to produce a prepreg for a metal foil-clad laminate. The substrate is not particularly limited, and cloth or nonwoven fabric using fibers such as glass fiber, aramid fiber, polyester fiber, and nylon fiber, or paper such as kraft paper and linter paper can be used. In addition, inorganic fibers such as glass cloth are preferable because they have excellent heat resistance and moisture resistance. As a method of solidifying, the solvent in the epoxy resin composition is removed by heating, and the curing of the epoxy resin composition is advanced to a B stage (semi-cured) state, and then cooled to a solid state. Is generally performed. When a solid epoxy resin composition is heated and melted at room temperature and then impregnated into a substrate, it can be cooled only.

The amount of the resin in the prepreg is preferably 40 to 80 parts by weight based on 100 parts by weight of the prepreg. If the amount is less than 40 parts by weight, air bubbles may remain in the metal foil-clad laminate manufactured using this prepreg and electrical reliability may be reduced. Also, 80
When the amount exceeds the weight part, the thickness variation of the metal foil-clad laminate manufactured using this prepreg may increase.

A metal foil-clad laminate is manufactured by laminating a required number of prepregs, arranging and laminating a metal foil such as a copper foil on one or both sides thereof, and performing molding by heating and pressing. Further, a laminate having a copper circuit formed on the surface thereof (a laminate using the epoxy resin composition according to the present invention, a laminate using another epoxy resin composition, or a laminate using another thermosetting resin composition) may be used. The prepreg obtained above is disposed on both sides or one side thereof, and a metal foil is disposed on the outer side of the prepreg and laminated, and then heated and pressed to form a multi-layered metal foil. A laminated laminate is obtained. The metal foil-clad laminate obtained in this manner has a small amount of finely cured resin formed on the surface of the metal foil and has a good glass transition temperature.

[0035]

【Example】

(Examples 1 to 4, Comparative Examples 1 and 2) The following three types of epoxy resins, amine-based curing agents, curing accelerators, linear block polymers, and solvents were used as raw materials for epoxy resin compositions. -Epoxy resin 1: a tetrabromobisphenol A type epoxy resin having an epoxy equivalent of 500 [DER511 manufactured by Dow Chemical Co., Ltd.]-Epoxy resin 2: a cresol novolac type epoxy resin having an epoxy equivalent of 220 [Toto Kasei Co., Ltd.
-Epoxy resin 3: a brominated phenol novolak-type epoxy resin having an epoxy equivalent of 280 [trade name: BREN, manufactured by Nippon Kayaku Co., Ltd.]-Amine-based curing agent: dicyandiamide [reagent], A curing accelerator: 2-ethyl-4-methylimidazole [manufactured by Shikoku Chemicals Co., Ltd.]; and a linear block polymer: a structure represented by the above formulas (a), (b) and (c). A linear block polymer having a unit and a Vicat softening point of 72 ° C. [trade name # 6000-EP, manufactured by Denki Kagaku Kogyo Co., Ltd.] Solvent 1: ethylene glycol butyl ether [reagent]
Solvent 2: methyl ethyl ketone [reagent].

Each of the above-mentioned raw materials was blended in the weight ratio shown in Table 1, and then mixed and dissolved with a disper to obtain a liquid epoxy resin composition.

[0037]

[Table 1]

Next, the obtained epoxy resin composition is
After impregnating a glass cloth (product name: 7628W, manufactured by Asahi Schwebel Co., Ltd.) with a thickness of 0.18 mm, the resin is semi-cured by heating at 150 ° C., and then cooled and solidified to obtain a resin amount of 50% by weight. Prepreg was obtained.

Next, eight prepregs obtained were laminated, and a copper foil having a thickness of 18 μm [trade name: JTC manufactured by Nikko Gould Foil Co., Ltd.] was disposed on both outer sides thereof. Sandwiched between plates, maximum temperature 17
Molding was performed under the conditions of 0 ° C., a pressure of 3.9 MPa, and a time of 90 minutes to obtain a metal foil-clad laminate having a size of 1 × 1 m and a thickness of 1.6 mm.

(Evaluation and Results) The amount of resin powder scattered was measured for the prepregs obtained in each of the examples and comparative examples.
As a measuring method, a prepreg was cut into 10 × 10 cm, and 12 sheets were piled up as a measurement sample, and four sides of the measurement sample were dropped on a platen five times from a height of 5 cm each five times. The resin scattered on the surface plate was sampled and the weight was measured.

As shown in Table 1, it was confirmed that each example was a prepreg in which the amount of scattered resin powder was smaller in each example than in each comparative example, and powder in which the resin was broken was less likely to be generated.

Further, for the metal foil-clad laminates obtained in each of the examples and comparative examples, the resin cured product generation rate and the glass transition temperature were measured. The resin cured product generation rate was evaluated by evaluating the presence or absence of a resin cured product having a size of φ0.5 mm or more and a depth of 50 μm or more generated on the copper foil on the surface of the metal foil-clad laminate on 1,000 sheets. The occurrence rate was determined from the number of foil-clad laminates. The glass transition temperature was determined by etching the entire outer copper foil of the metal foil-clad laminate,
It was determined based on the DSC method of IS standard C6481.

As shown in Table 1, it was confirmed that each of the examples had a lower resin cured product generation rate and a substantially equal glass transition temperature as compared with the comparative examples. That is, the prepreg obtained in each of the examples is a prepreg in which the broken powder of the resin is unlikely to be generated in handling or the like,
It was confirmed that a metal foil-clad laminate excellent in glass transition temperature was obtained, which was almost equivalent to the comparative example containing no linear block polymer.

[0044]

When the epoxy resin composition for a metal foil-clad laminate according to any one of claims 1 to 5 of the present invention is used, a metal foil-clad laminate having an excellent glass transition temperature can be obtained, and at the same time, in handling and the like. As a result, a prepreg in which resin broken powder is hardly generated can be obtained.

Further, according to the prepreg for a metal foil-clad laminate according to claims 6 and 7 of the present invention, a metal foil-clad laminate having an excellent glass transition temperature can be obtained, and the resin is broken during handling and the like. It becomes a prepreg that hardly generates powder.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08L 53:00)

Claims (7)

[Claims] 1. An epoxy resin, an amine-based curing agent, a curing accelerator, and a linear block polymer having structural units represented by the following formulas (a), (b) and (c): An epoxy resin composition for a metal foil-clad laminate characterized by containing. Embedded image 2. The epoxy resin composition for a metal foil-clad laminate according to claim 1, wherein the epoxy resin composition contains 1 to 8 parts by weight of a linear block polymer based on 100 parts by weight of the total epoxy resin. 3. An epoxy for a metal foil-clad laminate according to claim 1, wherein the linear block polymer contains a linear block polymer having a Vicat softening point of 55 to 100 ° C. Resin composition. 4. The epoxy resin composition for a metal foil-clad laminate according to claim 1, wherein dicyandiamide is contained as an amine-based curing agent. 5. A tetrabromobisphenol A type epoxy resin is used in an amount of 50 to 1 based on 100 parts by weight of all epoxy resins.
The epoxy resin composition for a metal foil-clad laminate according to any one of claims 1 to 4, wherein the epoxy resin composition is contained in an amount of 00 parts by weight. 6. A prepreg for a metal foil-clad laminate obtained by impregnating a base material with the epoxy resin composition for a metal foil-clad laminate according to any one of claims 1 to 5 and then solidifying it. 7. The prepreg for a metal foil-clad laminate according to claim 6, wherein the substrate is a glass cloth.