JP4277565B2 - Resin composition for printed wiring board and use thereof - Google Patents

Description

【００４１】
【発明の効果】
本発明の樹脂組成物を用いることにより、ピール強度、耐熱性が良好で、かつＴｇが低下することなく、成形時の樹脂流れが向上したプリプレグが得られ、またこのプリプレグを使用することで高板厚精度の積層板を提供することができる。[0001]
[Industrial application fields]
The present invention relates to a resin composition for a printed wiring board, and a resin varnish, a prepreg and a laminate using the same.
[0002]
[Prior art]
For example, a metal foil-clad laminate used in electrical and electronic equipment is made by, for example, impregnating a base material such as glass cloth with a thermosetting resin varnish such as an epoxy resin composition, and then heating and semi-curing the prepreg. The prepreg is manufactured by stacking a required number of sheets, laminating a metal foil such as a copper foil on one side or both sides, and forming by heating and pressing. In addition, the multilayer metal foil-clad laminate is formed on the front and back of the laminate on which the conductor circuit is formed after etching the metal foil on the surface of the metal foil-clad laminate obtained by the above method to form a conductor circuit. A prepreg similar to that described above is stacked, and a metal foil is disposed on one side or both sides of the prepreg, stacked, and heated and pressed to form. As the epoxy resin composition, a low molecular weight epoxy resin having an epoxy equivalent of about 100 to 1000, an amine curing agent, and a curing accelerator are generally used.
[0003]
In recent years, with the demand for higher density and high-speed transmission of printed wiring boards, printed wiring board materials are also required to have improved board thickness accuracy and interlayer thickness accuracy to control insulation reliability, high heat resistance, and impedance characteristics. Has been. In addition, with the demand for thinner printed wiring boards, the thickness of base materials and copper foils has been reduced, and the improvement of the adhesive strength between the base material and copper foil is also required.
[0004]
[Problems to be solved by the invention]
In order to improve the plate thickness accuracy, it is an effective means to suppress the resin flow during molding by changing the molding pressure and heating conditions during heating molding and by changing auxiliary materials. In addition, the plate thickness accuracy is improved by optimizing the gel time. However, in the resin varnish using the low molecular weight epoxy as described above, even if the resin flow and the gelation time are optimized, it is difficult to suppress the resin flow during molding, and sufficient plate thickness accuracy cannot be obtained. Therefore, blending a linear high molecular weight resin component, a rubbery component and a filler into the resin varnish is an effective means for suppressing the resin flow of the prepreg. However, the blending of fillers tends to decrease the punching characteristics, drilling workability, heat resistance, etc. when processing printed wiring boards, and linear high molecular weight epoxy resins (for example, phenoxy resins) and rubber-like When the components are blended singly, the appearance of the prepreg at the time of drying deteriorates as the amount added increases, and the Tg, heat resistance and peel strength of the resulting laminate are reduced.
[0005]
In response to such a requirement, a linear epoxy resin having an epoxy group at a reaction terminal having an epoxy equivalent of 100 to 1000 and a weight average molecular weight of 10,000 or more, and an epoxy equivalent of 100 to 1000 and a weight average molecular weight of 5000 or less. It has been proposed to improve plate thickness accuracy by using an epoxy resin composition in combination with an epoxy resin (see, for example, Patent Document 1). However, this epoxy resin composition has been required to further improve the peel strength while maintaining good Tg and heat resistance when used as a printed wiring board.
[0006]
[Patent Document 1]
JP-A-2002-114855 [0007]
[Problems to be solved by the invention]
An object of the present invention is to provide a resin composition for a printed wiring board in which a prepreg having good heat resistance and peel strength and improved resin flow during molding can be obtained without lowering Tg.
[0008]
[Means for Solving the Problems]
The present invention includes (a) a linear epoxy resin having an epoxy equivalent of 100 or more and 300 or less and a weight average molecular weight of 500 or less, and (b) an epoxy equivalent of 500 or more and 1000 or less, and a weight. An epoxy resin having an epoxy group at the reaction terminal having an average molecular weight of 10,000 or more, (c) an epoxy resin having an epoxy equivalent of 100 or more and 1000 or less, and a weight average molecular weight of more than 500 and 5000 or less, ( d) a curing agent, and (e) a curing accelerator, and (a) component is 0.1 to 2 parts by weight with respect to 100 parts by weight in total of component (a), component (b) and component (c). It is related with the resin composition for printed wiring boards whose (b) component is 1-15 weight part. Moreover, this invention relates to the resin varnish for printed wiring boards using this resin composition for printed wiring boards, the prepreg for printed wiring boards, and a metal-clad laminated board.
[0009]
In the resin composition of the present invention, (a) a linear epoxy resin having an epoxy equivalent of 100 or more and 300 or less and a weight average molecular weight of 500 or less is not particularly limited. For example, bisphenol A type epoxy resin And liquid epoxy resins such as bisphenol F-type epoxy resins. In the present specification, the weight average molecular weight is a value measured by high performance liquid chromatography.
[0010]
(A) As for the epoxy equivalent of the epoxy resin of a component, 150-250 are preferable, More preferably, it is 180-190. The weight average molecular weight is preferably 300 to 500, and more preferably 350 to 450. The component (a) preferably has a high purity of 99.9% or more from the viewpoint of heat resistance. Further, from the viewpoint of curability and heat resistance, those having an amount of hydrolyzable chlorine as an impurity of 200 ppm or less are preferable. The epoxy resin as component (a) can be used alone or in combination of two or more. Here, the amount of hydrolyzable chlorine means a value obtained by hydrolyzing an epoxy resin with a potassium hydroxide solution and measuring the amount of ionized chlorine by measuring the consumption amount of potassium hydroxide.
[0011]
In the resin composition of the present invention, (b) the epoxy resin having an epoxy equivalent of 500 or more and 1000 or less and having an epoxy at the reaction terminal having a weight average molecular weight of 10,000 or more is not particularly limited. The epoxy resin as component (b) is preferably an epoxy resin having a linear unit, and an epoxy resin obtained by further oligomerizing a linear oligomerized epoxy resin with an amine or the like is particularly preferable. For example, a resin obtained by reacting bisphenol A diglycidyl ether with an acid anhydride and polymerized with diaminodiphenylmethane, having an epoxy group at the reaction end, having an epoxy equivalent of 500 or more, And those having a weight average molecular weight of 10,000 or more.
[0012]
As for the epoxy equivalent of the epoxy resin of (b) component, 600-900 are preferable, More preferably, it is 700-800. The weight average molecular weight is preferably 10,000 to 50,000, more preferably 10,000 to 30,000. The epoxy resin as component (b) can be used alone or in combination of two or more.
[0013]
In the resin composition of the present invention, (c) an epoxy resin having an epoxy equivalent of 100 or more and 1000 or less, a weight average molecular weight of more than 500, and 5000 or less has two or more epoxy groups in the molecule. If it has, it will not specifically limit. Further, the epoxy resin of component (c) may be linear or branched. For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, alicyclic epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol A novolac type epoxy resin, difunctional phenol di Examples thereof include glycidyl etherified products, diglycidyl etherified products of polyfunctional alcohols, halides thereof, and hydrogenated products thereof. Specifically, brominated bisphenol A type epoxy resin can be used.
[0014]
As for the epoxy equivalent of the epoxy resin of (c) component, 300-600 are preferable, More preferably, it is 450-500. The weight average molecular weight is preferably 1,000 to 3,000, more preferably 1,500 to 2,500. The epoxy resin as component (c) can be used alone or in combination of two or more.
[0015]
The (d) curing agent in the resin composition of the present invention is not particularly limited as long as it is used as an epoxy resin curing accelerator, and examples thereof include amines, phenols, and acid anhydrides. Those usually used for electrical insulating varnishes are preferred.
[0016]
Examples of amines include diethylamine, diethylenetriamine, triethylenetetramine, diethylaminopropylamine, aminoethylpiperazine, mensendiamine, metaxylylenediamine, dicyandiamide, diaminodiphenylmethane, diaminodiphenylsulfone, methylenedianiline, and metaphenylenediamine. .
[0017]
Examples of the phenols include biphenol, bisphenol A, bisphenol F, phenol novolak, cresol novolak, bisphenol A novolak, halides thereof, alkyl group (for example, methyl group, ethyl group and the like) substituents, and the like.
[0018]
Acid anhydrides include hexahydrophthalic anhydride (HPA), tetrahydrophthalic anhydride (THPA), pyromellitic anhydride (PMDA), chlorendic anhydride (HET), nadic anhydride (NA), and methyl nadic anhydride (MNA), dodecynyl succinic anhydride (DDSA), phthalic anhydride (PA), methylhexahydrophthalic anhydride (MeHPA), maleic anhydride and the like.
[0019]
The curing agent as component (d) is preferably an amine, and particularly preferably dicyandiamide. (D) The hardening | curing agent of a component can also be used individually or in combination with 2 or more types.
[0020]
Examples of the (e) curing accelerator in the resin composition of the present invention include an imidazole compound, an organic phosphorus compound, a tertiary amine, a quaternary ammonium salt, etc., but the secondary amino group is acrylonitrile, isocyanate, An imidazole compound masked with melamine, acrylate or the like is preferable from the viewpoint of storage stability of the prepreg.
[0021]
As the imidazole compound, imidazole, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-undecylimidazole, 1-benzyl-2-methylimidazole, 2-heptadecylimidazole, 4,5 -Diphenylimidazole, 2-methylimidazoline, 2-ethyl-4-methylimidazoline, 2-phenylimidazoline, 2-undecylimidazoline, 2-heptadecylimidazoline, 2-isopropylimidazole, 2,4-dimethylimidazole, 2-phenyl Examples include -4-methylimidazole, 2-methylimidazoline, 2-isopropylimidazoline, 2,4-dimethylimidazoline, 2-phenyl-4-methylimidazoline.
Examples of the masking agent include acrylonitrile, phenylene diisocyanate, toluene diisocyanate, naphthalene diisocyanate, hexamethylene diisocyanate, methylene bisphenyl isocyanate, and melamine acrylate. (E) The hardening accelerator of a component can also be used individually or in combination with 2 or more types.
[0022]
In the resin composition of the present invention, the amount of the (a) component, the (b) component, and the (c) component epoxy resin is 100 parts by weight in total of the (a) to (c) component epoxy resins. (A) component is 0.1-2 weight part, Preferably it is 1-2 weight part, (b) component is 1-15 weight part, Preferably it is 3-10 weight part. When component (a) is blended within the above range, it is preferable from the viewpoint of peel strength and Tg, and when component (b) is blended within the above range, it is preferable from the viewpoint of resin flow and Tg.
[0023]
From the compounding quantity of said (a) component and (b) component, (c) component is 83-98.9 weight part with respect to the sum total of (a)-(c) component, Preferably, it is 88 -96 parts by weight.
[0024]
In the resin composition of the present invention, the component (d) is preferably 1 to 4 parts by weight, more preferably 1.5 parts with respect to 100 parts by weight of the total of the epoxy resins of the components (a) to (c). ~ 3 parts by weight. When the component (d) is blended in the above range, it is preferable from the viewpoint of heat resistance and Tg.
[0025]
In the resin composition of the present invention, the component (e) is preferably 0.1 to 0.5 parts by weight, more preferably based on 100 parts by weight of the total of the epoxy resins of the components (a) to (c). Is 0.2 to 0.3 parts by weight. When (e) component is mix | blended in said range, it is preferable from the point of heat resistance and Tg.
[0026]
In addition to the above components, a colorant, an antioxidant, a reducing agent, an ultraviolet opaque agent, and the like may be added to the resin composition of the present invention as necessary. Moreover, you may add a filler to such an extent that punch workability and drill workability are not reduced.
[0027]
The resin composition of the present invention can be diluted with a solvent to obtain a resin varnish. The solvent is not particularly limited, but for example, ketones such as methyl ethyl ketone, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone; alcohols such as methanol, ethanol, ethylene glycol, propylene glycol monomethyl ether; N-methylformamide, N, N -Solvents such as amides such as dimethylformamide, N, N-dimethylacetamide and N-methylpyrrolidone. The solvent is preferably used in the range of 30% to 70% by weight with respect to the total weight of the resin composition.
[0028]
Moreover, a prepreg can be obtained by impregnating a glass woven fabric or a glass nonwoven fabric with the resin composition of the present invention or the above resin varnish and drying it. The drying conditions for producing the prepreg can be freely selected according to the prepreg characteristics, and examples include a drying temperature of 60 to 200 ° C. and a drying time of 1 to 30 minutes.
[0029]
Although the kind of glass woven fabric or glass nonwoven fabric used here is not specifically limited, For example, the thing of the range of thickness 0.02-0.4mm is used according to the thickness of the target prepreg or laminated board. be able to.
[0030]
A prepreg obtained according to the thickness of the target laminate can be laminated, a metal foil can be placed on one or both sides, and heated and pressed to produce a laminate. As the metal foil, copper foil or aluminum foil is mainly used, but other metal foil may be used. Although the thickness of metal foil is not specifically limited, The range of 5-200 micrometers is mentioned. The heating temperature and pressure during the production of the laminated plate can be selected depending on the prepreg characteristics, the capacity of the press, the thickness of the desired laminated plate, and the like. For example, heating at 130 to 200 ° C, preferably 160 to 180 ° C The temperature is 0.5 to 10 MPa, preferably 1 to 4 MPa.
[0031]
Furthermore, it can be set as a printed wiring board by carrying out circuit processing of the metal foil of this laminated board. In the production of these prepregs, laminates, and printed wiring boards, ordinary coating, lamination, and circuit processing techniques in the industry can be applied.
[0032]
【Example】
EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. “Parts” indicates “parts by weight”.
[0033]
(Example 1)
(A) Component: DER331L (manufactured by Dow Chemical) 1 part (bisphenol A type epoxy resin, epoxy equivalent 185, weight average molecular weight 400)
(B) Component: 9 parts of XZ-92505 (manufactured by Dow Chemical) (epoxy equivalent 800, weight average molecular weight 10,000)
Component (c): 90 parts of brominated bisphenol A type epoxy resin (epoxy equivalent 480, weight average molecular weight 1900)
(D) Component: Dicyandiamide 2.5 parts (e) Component: 2-ethyl-4-methylimidazole 0.2 parts The above components were dissolved in methyl ethyl ketone to prepare a varnish having a nonvolatile content of 65%. The gel time at 160 ° C. of this varnish was 200 seconds. This varnish was impregnated into a glass woven fabric (thickness 0.2 mm, basis weight 210 g / m ² ) so that the resin content was 45%, dried at 170 ° C. for 5 minutes, and the gelation time at 170 ° C. was 70. A second prepreg was obtained. Four prepregs were stacked, 18 μm copper foil was placed on both sides, and press molded at 170 ° C. for 90 minutes at 4 MPa to obtain a FR-4 laminate having a thickness of 0.8 mm.
[0034]
(Example 2)
(A) Component: DER331L (manufactured by Dow Chemical) 2 parts (bisphenol A type epoxy resin, epoxy equivalent 185, weight average molecular weight 400)
Component (b): XZ-92505 (manufactured by Dow Chemical) 8 parts (epoxy equivalent 800, weight average molecular weight 10,000)
Component (c): 90 parts of brominated bisphenol A type epoxy resin (epoxy equivalent 480, weight average molecular weight 1900)
(D) Component: Dicyandiamide 2.5 parts (e) Component: 2-ethyl-4-methylimidazole 0.2 part Using the above components and methyl ethyl ketone, the same prepreg gelation time as in Example 1 was obtained. A varnish was prepared. Next, using this varnish, a prepreg was produced in the same manner as in Example 1 to obtain a FR-4 laminate having a thickness of 0.8 mm.
[0035]
(Comparative Example 1)
(A) component: DER331L (made by Dow Chemical) 3 parts (bisphenol A type epoxy resin, epoxy equivalent 185, weight average molecular weight 400)
(B) Component: 7 parts of XZ-92505 (manufactured by Dow Chemical) (epoxy equivalent 800, weight average molecular weight 10,000)
Component (c): 90 parts of brominated bisphenol A type epoxy resin (epoxy equivalent 480, weight average molecular weight 1900)
(D) Component: Dicyandiamide 2.5 parts (e) Component: 2-ethyl-4-methylimidazole 0.2 part Using the above components and methyl ethyl ketone, the same prepreg gelation time as in Example 1 was obtained. A varnish was prepared. Next, using this varnish, a prepreg was produced in the same manner as in Example 1 to obtain a FR-4 laminate having a thickness of 0.8 mm.
[0036]
(Comparative Example 2)
(B) Component: DER331L (manufactured by Dow Chemical) 2 parts (bisphenol A type epoxy resin, epoxy equivalent 185, weight average molecular weight 400)
Component (c): 98 parts brominated bisphenol A type epoxy resin (epoxy equivalent 480, weight average molecular weight 1900)
(D) Component: Dicyandiamide 2.5 parts (e) Component: 2-ethyl-4-methylimidazole 0.2 part Using the above components and methyl ethyl ketone, the same prepreg gelation time as in Example 1 was obtained. A varnish was prepared. Next, using this varnish, a prepreg was produced in the same manner as in Example 1 to obtain a FR-4 laminate having a thickness of 0.8 mm.
(Comparative Example 3)
(B) Component: 10 parts of XZ-92505 (manufactured by Dow Chemical) (epoxy equivalent 800, weight average molecular weight 10,000)
Component (c): 90 parts of brominated bisphenol A type epoxy resin (epoxy equivalent 480, weight average molecular weight 1900)
(D) Component: Dicyandiamide 2.5 parts (e) Component: 2-ethyl-4-methylimidazole 0.2 part Using the above components and methyl ethyl ketone, the same prepreg gelation time as in Example 1 was obtained. A varnish was prepared. Next, using this varnish, a prepreg was produced in the same manner as in Example 1 to obtain a FR-4 laminate having a thickness of 0.8 mm.
[0037]
(Comparative Example 4)
Component (c): 100 parts of brominated bisphenol A type epoxy resin (epoxy equivalent 480, weight average molecular weight 1900)
(D) Component: Dicyandiamide 2.6 parts (e) Component: 2-ethyl-4-methylimidazole 0.2 part Using the above components and methyl ethyl ketone, the same prepreg gelation time as in Example 1 was obtained. A varnish was prepared. Next, using this varnish, a prepreg was produced in the same manner as in Example 1 to obtain a FR-4 laminate having a thickness of 0.8 mm.
[0038]
The resin flow was measured for the prepregs obtained in Examples 1 and 2 and Comparative Examples 1 to 4, and the sheet thickness accuracy, Tg, heat resistance, and peel strength (copper foil peel strength) of the laminate using this prepreg. Was measured as follows.
Prepreg resin flow: Measured according to JIS-C-6521.
Plate thickness accuracy: The plate thickness was measured according to JIS-C-6481, and the standard deviation was calculated.
Tg: Measured according to JIS-C-6481 using TMA.
Peel strength: measured in accordance with JIS-C-6481.
Heat resistance: The copper foil on the surface of the laminate was removed by etching, immersed in a solder bath at 280 ° C. for 20 seconds, and the presence or absence of measling or swelling was visually evaluated. The evaluation criteria were as follows: ○: no abnormality, Δ: occurrence of mesuring, and ×: occurrence of swelling.
[0039]
As is clear from the results in Table 1, in Examples 1 and 2 using varnishes containing the epoxy resins of the components (a) to (c) in a specific blending amount, heat resistance and peel strength are good, and The resin flow is reduced without a decrease in Tg, and the plate thickness accuracy is improved. On the other hand, in Comparative Example 1 in which the blending amounts of the component (a) and the component (b) are out of the range of the present invention, it is understood that Tg is low and heat resistance is also inferior. In addition, as in Comparative Examples 2 and 3, when either one or both of the component (a) and the component (b) is not included, any deterioration in characteristics such as heat resistance, resin flow, Tg, and peel strength may occur. Be looked at.
[0040]
[Table 1]

[0041]
【The invention's effect】
By using the resin composition of the present invention, a prepreg having excellent peel strength and heat resistance and improved resin flow at the time of molding without lowering Tg can be obtained. A laminated plate with a plate thickness accuracy can be provided.

Claims (4)

(A) a linear epoxy resin having an epoxy equivalent of 100 or more and 300 or less and a weight average molecular weight of 500 or less;
(B) an epoxy resin having an epoxy group at the terminal, having an epoxy equivalent of 500 or more and 1000 or less, and a weight average molecular weight of 10,000 or more;
(C) an epoxy resin having an epoxy equivalent of 100 or more and 1000 or less, a weight average molecular weight of more than 500 and 5000 or less,
(D) a curing agent, and (e) a curing accelerator, and (a) component is 0.1 to 2 weight with respect to a total of 100 parts by weight of component (a), component (b) and component (c). Part, and the resin composition for printed wiring boards whose (b) component is 1-15 weight part.   A resin varnish for a printed wiring board obtained by dissolving or dispersing the resin composition according to claim 1 in a solvent.   A printed wiring board prepreg obtained by impregnating a glass woven fabric or a glass nonwoven fabric with the resin composition according to claim 1 or the resin varnish for printed wiring board according to claim 2 and heating to form a B stage.   A metal-clad laminate obtained by stacking at least one prepreg for a printed wiring board according to claim 3, laminating a metal foil on at least one surface thereof, and heating and pressing.