JP2011021205A - Insulating resin composition for printed wiring board and application thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a halogen-free insulating resin sheet excellent in copper foil peeling strength and chemical resistance. <P>SOLUTION: An insulating resin composition is an epoxy resin composition containing a polyphenolic antioxidant. The epoxy resin composition is a resin composition including an epoxy resin, phenolic hardener, compound having a dihydrobenzoxazine ring, polyvinyl butyral resin and inorganic filler. A method of manufacturing a printed wiring board using the epoxy resin composition is described. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an insulating resin material having high chemical resistance and copper foil peeling strength (peel strength), which is useful for manufacturing a multilayer printed wiring board.

  As miniaturization of consumer electronic devices progresses, printed wiring boards used for them tend to have higher density and finer wiring. In recent years, a thin multilayer printed wiring board by a build-up method using a resin-coated copper foil corresponding to a thin fine pitch has been widely used. In addition, mainly in Europe, awareness of environmental issues has increased, and materials that do not cause the generation of harmful gases such as dioxins during incineration such as disposal, especially halogen-free insulating resin materials, are being introduced. For this reason, there is a demand for improvements in the copper foil peeling strength, solvent resistance, and the like for multilayer printed wiring boards that use halogen-free insulating resin sheets.

  Conventionally, in a halogen-free multilayer printed wiring board, a bisphenol antioxidant has been added to the epoxy resin composition used for the insulating resin sheet. However, an insulating resin sheet obtained from a resin composition containing a bisphenol-based antioxidant is not sufficiently cured by press molding under pressure and heating. Therefore, the obtained printed wiring board was inferior in copper foil peeling strength and chemical resistance.

  An object of the present invention is to provide a halogen-free insulating resin sheet excellent in copper foil peeling strength and chemical resistance.

  The present invention is a resin composition comprising an epoxy resin, a phenolic curing agent, a compound having a dihydrobenzoxazine ring, a polyvinyl butyral resin, and an inorganic filler, characterized in that it contains a polyphenolic antioxidant. The present invention relates to a resin composition.

  The present invention further relates to an insulating resin sheet obtained by applying and drying the above resin composition to a copper foil or a carrier film, and an electronic device using the resin sheet.

  The epoxy resin composition containing a polyphenol-based antioxidant which is halogen-free according to the present invention and the insulating resin sheet for multilayer printed wiring boards using the composition according to the present invention have increased copper foil peeling strength and are resistant to resistance. There is an excellent effect of improving chemical properties.

Hereinafter, examples of the present invention will be described in detail.
As the epoxy resin that can be used in the present invention, a bifunctional or higher functional epoxy resin can be used. For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, dendritic epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol A novolac type epoxy resin, polyfunctional phenol digly There exist a dietherified substance, these hydrogenated substances, etc., and it can be used individually or in combination of 2 or more types. Moreover, the molecular weight with respect to this epoxy resin and the method of mixing these epoxy resins are not restrict | limited to temperature.

  The phenolic curing agent that can be used in the present invention is a phenolic curing agent having two or more phenolic hydroxyl groups. For example, a novolak resin etc. are mentioned, A phenol novolak resin, a cresol novolak resin, a xylene-novolak resin, a melamine-novolak resin, etc. are preferable, These can be used individually or in combination.

  As the compound having a dihydrobenzoxazine ring that can be used in the present invention, a resin system that cures by a ring-opening reaction of a dihydrobenzoxazine ring can be used. For example, it can be produced from a compound having a phenolic hydroxyl group, formalin and a primary amine. Examples of the compound having a phenolic hydroxyl group include polyfunctional phenols and polycyclic phenols, and biphenol compounds, bisphenol compounds, trisphenol compounds, tetraphenol compounds, and phenol resins are preferable. Examples of the primary amine include unsubstituted or substituted alkylamine, cycloamine, and aniline, and methylamine, cyclohexylamine, aniline, substituted aniline, and the like are preferable.

  The degree of polymerization or degree of butyralization of the polyvinyl butyral resin of the present invention is not limited. However, those having an average degree of polymerization of 500 to 3000 and a degree of butyralization of 60 mol% or more are preferred. Furthermore, it is more preferable that the average degree of polymerization is 1500 to 2500 and the degree of butyralization is 65 mol% or more. For example, Eslex BX-1 (manufactured by Sekisui Chemical Co., Ltd .: average polymerization degree 1700, butyralization degree 65 mol%), Eslex BX-2 (manufactured by Sekisui Chemical Co., Ltd .: average polymerization degree 1700, butyralization degree) 65 mol%), electrified butyral 4000-2 (manufactured by Denki Kagaku Kogyo Co., Ltd .: average polymerization degree 1000, butyral degree of 75 mol%), electrified butyral 5000-A (manufactured by Denki Kagaku Kogyo Co., Ltd .: average degree of polymerization 2000, butyral) Conversion degree 80 mol%). These resins can be used alone or in combination of two or more. The blending amount of polyvinyl butyral is preferably 5 to 30 parts by weight per 100 parts by weight of the total amount of the solid varnish, considering the balance between film forming properties, flame retardancy and heat resistance.

  As fillers that can be used in the present invention, inorganic fillers, organic fillers, reinforcing fibers, and the like can be used. For example, staple fiber, yarn, cotton cloth, glass cloth, glass mat, glass fiber, carbon fiber, quartz fiber, flame retardant synthetic fiber, silica powder, calcium carbonate magnesium hydroxide, aluminum hydroxide, etc., alone or Can be used in combination. These fillers are effective in improving the interfacial adhesion to the resin if the surface is subjected to hydrophobic treatment with a coupling agent in advance. The blending amount of the filler is preferably 20 to 60 parts by weight and more preferably 30 to 50 parts by weight in consideration of the balance between film forming property and flame retardancy per 100 parts by weight of the total amount of the solid varnish.

  As the polyphenol-based antioxidant that can be used in the present invention, trivalent or higher polyphenols are preferable. Further, trihydroxybenzene is preferable, and examples thereof include 1,2,3-trihydroxybenzene, 1,2,4-trihydroxybenzene, and 1,3,5-trihydroxybenzene. These antioxidants can be used alone or in combination of two or more. The blending amount is preferably 0.1 to 5.0 parts by weight and more preferably 0.5 to 2.0 parts by weight in consideration of the balance between the antioxidant effect and the varnish curing time per 100 parts by weight of the filler.

  The resin composition of the present invention can be used after adding an organic solvent and varnishing if desired. As an organic solvent, what dissolve | melts the resin part except a filler can be used. For example, alcohol, acetone, toluene, xylene, ketone, amide, pyrrolidone and the like can be mentioned, and methanol, ethanol, isopropyl alcohol, toluene, methyl ethyl ketone, cyclohexanone, dimethylformamide, and N-methylpyrrolidone are preferable. These can be used alone or in combination of two or more.

  As mentioned above, after apply | coating to the carrier film the varnish-like resin composition obtained by the mixing | blending of this invention, a solvent is removed in the range of 60 degreeC-180 degreeC, it is made to thermoset, and an insulating resin sheet is used. Can be used for production. The application method is not particularly limited. In the present invention, the carrier film is an organic film that can withstand a drying temperature (60 to 180 ° C.) such as PET, PBT, and PPO, a metal foil such as copper, aluminum, nickel, silver, and the like. Can be used in combination. The insulating resin sheet of the present invention is placed on both sides of a circuit-processed double-sided wiring board, laminated, and then press-laminated under vacuum (for example, holding temperature 180 ° C., holding pressure 3.0 MPa, holding time 90 minutes) ), A multilayer printed wiring board can be manufactured. In view of good moldability and resin performance, the press lamination (thermocompression bonding) is preferably a holding temperature of 170 to 220 ° C, more preferably 180 to 200 ° C. The pressure is preferably 2.0 to 7.0 MPa, more preferably 3.0 to 5.0 MPa. The holding time is preferably 10 to 180 minutes, more preferably 70 to 120 minutes.

An insulating resin sheet can be formed from the resin composition of the present invention. The sheet | seat of this invention means the solidified thing which dried the resin composition of this invention and has a fixed shape. Preferably, it is layered or film-like, and these can be laminated and used. In addition, the sheet of the present invention can be further formed into a desired shape. The sheet of the present invention has excellent chemical resistance, and the weight loss in an alkaline solution is preferably 100 μg · cm ⁻² or less, more preferably 80 μg · cm ⁻² or less.

Further, the sheet of the present invention has a copper foil peeling strength when laminated, preferably 0.90 kN · m ⁻¹ or more, more preferably 0.95 kN · m ⁻¹ or more.

  Although it does not specifically limit as an electronic device using the resin sheet of this invention, The copper clad laminated board for printed wiring boards etc. are mentioned. Moreover, the electronic device which uses the resin sheet of this invention for a part, for example, adhere | attaches with a wiring board or a semiconductor chip is included. For example, a BGA (ball grid array) package, an element mounting PGA (pin grid array), and the like can be given.

  EXAMPLES The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. In the examples, all parts are parts by weight.

Example 1
70 parts of bisphenol F epoxy resin (GK-5079: manufactured by Nippon Steel Chemical Co., Ltd.), compound having a dihydrobenzoxazine ring (VR-2000M: manufactured by Hitachi Chemical Co., Ltd.)) per 100 parts of filler , 15 parts of melamine modified phenolic resin (LA-7054: manufactured by Dainippon Ink & Chemicals, Inc.), 15 parts of polyvinyl butyral resin (HS-3Z: manufactured by Sekisui Chemical Co., Ltd.), aluminum hydroxide (CL-303: Sumitomo Chemical Co., Ltd.) 100 parts, 1,2,3-trihydroxybenzene (Pyrogallol: Wako Pure Chemical Industries, Ltd.) 0.5 part blended and mixed to form a varnish-like epoxy resin composition I got a thing. This composition is applied to a copper foil having a thickness of 12 μm and dried at 130 ° C. for 3 minutes and then at 150 ° C. for 3 minutes. The resin thickness is 80 μm, the resin flow is 10%, and the rheometer has a minimum melt viscosity of 3000 poise. An insulating resin sheet was obtained. The obtained insulating adhesive sheet was disposed on both sides of the inner layer board, and then thermocompression bonded for 90 minutes under a vacuum condition of a pressure of 3.0 MPa and a holding temperature of 180 ° C. to form a double-sided copper clad laminate.

  The copper foil peeling strength and chemical resistance of the obtained double-sided copper-clad laminate were evaluated by the following methods.

Evaluation method Copper foil peeling strength (peel strength): A 10 mm wide pattern was formed on the outer layer copper foil using a copper-clad laminate obtained by heat-pressing an insulating resin sheet. This outer layer copper foil was peeled off using a tensile tester (S-100, manufactured by Shimadzu Autograph) at a peeling speed of 50 mm · min ⁻¹ and evaluated by the force required for peeling.
Chemical resistance (alkali resistance): A substrate sample of 1 dm ² of the evaluation substrate etched on the entire surface was dried. Thereafter, it was immersed in a 5% sodium hydroxide solution preheated to 50 ° C. for a predetermined time. The difference in weight before and after the immersion treatment was determined, and the chemical resistance was evaluated based on the weight loss.

Example 2
A double-sided copper-clad laminate was formed and evaluated in the same manner as in Example 1 except that 0.5 part of 1,2,3-trihydroxybenzene was replaced with 5.0 parts.

Example 3
Example 1 was repeated except that 0.5 part of 1,2,3-trihydroxybenzene was replaced with 0.5 part of 1,2,4-trihydroxybenzene (manufactured by Wako Pure Chemical Industries, Ltd.). Then, a double-sided copper-clad laminate was formed and evaluated.

Example 4
Example 1 was repeated except that 0.5 part of 1,2,3-trihydroxybenzene was replaced with 0.5 part of 1,3,5-trihydroxybenzene (manufactured by Wako Pure Chemical Industries, Ltd.). Then, a double-sided copper-clad laminate was formed and evaluated.

Comparative Example 1
Both surfaces are the same as in Example 1 except that 0.5 part of 1,2,3-trihydroxybenzene is replaced with 0.5 part of 1,2-dihydroxybenzene (manufactured by Wako Pure Chemical Industries, Ltd.). A copper clad laminate was formed and evaluated.

Comparative Example 2
Both sides were carried out in the same manner as in Example 1 except that 0.5 part of 1,2,3-trihydroxybenzene was replaced with 0.5 part of bisphenol antioxidant (Yoshinox BB: manufactured by Maruzen Petrochemical Co., Ltd.). A copper clad laminate was formed and evaluated.

Comparative Example 3
A double-sided copper-clad laminate was formed and evaluated in the same manner as in Example 1 except that 1,2,3-trihydroxybenzene was not added.

  Table 1 shows the results of peel strength and chemical resistance of Examples 1 to 4 and Comparative Examples 1 to 3.

  As is clear from Table 1, the laminate produced using the composition of the present invention exhibited high copper foil peeling strength. In addition, the laminate of the present invention has a low weight reduction rate and is excellent in chemical resistance.

Claims (8)

  An epoxy resin comprising a epoxy resin, a phenolic curing agent, a compound having a dihydrobenzoxazine ring, a polyvinyl butyral resin, and a filler, and containing a trihydric or higher polyphenolic antioxidant. Composition.   The resin composition according to claim 1, wherein the polyphenol-based antioxidant is trihydroxybenzenes.   The polyphenol antioxidant is one or more selected from the group consisting of 1,2,3-trihydroxybenzene, 1,2,4-trihydroxybenzene and 1,3,5-trihydroxybenzene. The resin composition according to claim 1.   The resin composition according to any one of claims 1 to 3, wherein the polyphenol antioxidant is 0.1 to 5.0 parts by weight per 100 parts by weight of the filler.   The insulating resin sheet which apply | coated and dried the resin composition of any one of Claims 1-4 to copper foil or a carrier film. The sheet according to claim 5, which has a chemical resistance of 100 µg · cm ^-2 or less. The sheet according to claim 5 or 6, wherein the peel strength of the copper foil is 0.9 kN · m ^-1 or more.   The electronic device using the resin sheet of any one of Claims 5-8.