JP2013181132A - Epoxy resin material and multilayer board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an epoxy resin material low in thermal linear expansion coefficient of cured matter and capable of enhancing adhesion between the cured matter and a metal layer.SOLUTION: An epoxy resin material includes an epoxy resin, a curing agent and an inorganic filler. After thermally curing the epoxy resin material, the storage elastic modulus E' of the cured matter, measured at 250°C using a dynamic viscoelasticity measuring apparatus, is 2.0×10Pa or lower. After thermally curing the epoxy resin material, the linear expansion coefficient of the cured matter at 25-150°C is 30 ppm/°C or lower.

Description

  The present invention relates to an epoxy resin material that can be suitably used, for example, for forming an insulating layer in a multilayer substrate. The present invention also relates to a multilayer substrate using the epoxy resin material.

  Conventionally, various resin materials have been used in order to obtain electronic components such as laminated boards and printed wiring boards. For example, in a multilayer printed wiring board, a resin composition is used in order to form an insulating layer for insulating inner layers or to form an insulating layer located in a surface layer portion.

  The resin composition is often blended with an inorganic filler for the purpose of lowering the coefficient of thermal expansion. In recent years, along with miniaturization and high performance of electronic devices, the electronic components are also required to have finer wiring and further reduced thermal expansion coefficient in the insulating layer. In order to meet such a demand, an inorganic filler may be blended at a high concentration in the resin composition for forming the insulating layer.

  As an example of the resin composition, Patent Document 1 below discloses a resin composition containing a cyanate resin, a phenol resin, and an inorganic filler. Here, it is described that the resin composition has high flame retardancy and heat resistance and a low coefficient of linear expansion. Furthermore, Patent Document 1 describes that it is preferable to use an epoxy resin in order to improve the reactivity of the cyanate resin.

  Patent Document 2 below discloses a resin composition containing a compound having a heterocyclic group, an epoxy resin, and a cyanate compound. A filler can be added to this resin composition. Here, it is described that a cured product having low water absorption, excellent dielectric properties, and high heat resistance and dimensional stability can be obtained.

JP 2003-096296 A JP 2006-028498 A

  There is an increasing demand for miniaturization and high performance of the electronic components, and the electronic components are becoming thinner, densely integrated and densely packaged. For this reason, thinning of multilayer printed wiring boards and miniaturization of conductor wiring are progressing.

  As a method for forming a wiring on an insulating layer, a semi-additive method is known in which a wiring is formed by electroless plating and electrolytic plating after the surface of the insulating layer is roughened. In such a method, a roughening treatment is performed using a roughening solution such as an alkaline permanganate solution to form fine holes on the surface of the insulating layer. By forming fine holes in the surface of the insulating layer, a physical anchor effect can be obtained between the insulating layer and the wiring. The adhesion between the insulating layer and the wiring is enhanced by the anchor effect. The fine pores on the surface of the insulating layer are generally formed by dissolving the resin component in the roughening solution or by detaching the filler contained in the resin composition.

  In recent years, there has been an increasing demand for miniaturization of conductor wiring of multilayer printed wiring boards. Even if the conductor wiring is fine, high adhesion between the insulating layer and the wiring is required. In addition, in a multilayer printed wiring board on which high-density wiring is formed, there is a problem that a defect is likely to occur due to a crack generated due to a difference in the thermal linear expansion coefficient between the wiring and the insulating layer. For this reason, it is desirable that the thermal expansion coefficient of the insulating layer is low.

  When an insulating layer is formed using a conventional resin composition as described in Patent Documents 1 and 2, the thermal expansion coefficient of the insulating layer does not become sufficiently low, or the adhesion between the insulating layer and the metal layer There is a problem that is not high enough. Moreover, when an insulating layer is formed using a conventional resin composition, both lowering the thermal expansion coefficient of the insulating layer and increasing the adhesion between the insulating layer and the metal layer are compatible. It is difficult.

  An object of the present invention is to provide an epoxy resin material having a low thermal linear expansion coefficient of a cured product and capable of further improving the adhesion between the cured product and a metal layer, and a multilayer substrate using the epoxy resin material. .

According to a wide aspect of the present invention, the storage elastic modulus E at 250 ° C. measured using a dynamic viscoelasticity measuring device for a cured product after heat curing, including an epoxy resin, a curing agent, and an inorganic filler. An epoxy resin material is provided in which 'is 2.0 × 10 ⁸ Pa or less and the thermal linear expansion coefficient at 25 to 150 ° C. of the cured product after thermosetting is 30 ppm / ° C. or less.

  In a specific aspect of the epoxy resin material according to the present invention, the epoxy resin material further includes a thermoplastic resin.

  In another specific aspect of the epoxy resin material according to the present invention, the epoxy resin material is a B-stage film formed into a film shape.

  According to a wide aspect of the present invention, it includes a circuit board and a cured product layer disposed on the surface of the circuit board, and the cured product layer is formed by curing the above-described epoxy resin material. A multilayer substrate is provided.

The epoxy resin material according to the present invention includes an epoxy resin, a curing agent, and an inorganic filler, and a storage elastic modulus E at 250 ° C. measured using a dynamic viscoelasticity measuring device for a cured product after heat curing. 'Is 2.0 × 10 ⁸ Pa or less, and the thermal linear expansion coefficient at 25 to 150 ° C. of the cured product after thermosetting is 30 ppm / ° C. or less. The adhesion between the metal layer and the metal layer can be improved.

FIG. 1 is a partially cutaway front sectional view schematically showing a multilayer substrate using an epoxy resin material according to an embodiment of the present invention.

  Details of the present invention will be described below.

(Epoxy resin material)
The epoxy resin material according to the present invention includes an epoxy resin, a curing agent, and an inorganic filler. After thermally curing the epoxy resin material according to the present invention, the storage elastic modulus E ′ at 250 ° C. measured using a dynamic viscoelasticity measuring device (DMA) of the cured product is 2.0 × 10 ⁸ Pa or less. . After thermally curing the epoxy resin material according to the present invention, the thermal expansion coefficient of the cured product at 25 to 150 ° C. is 30 ppm / ° C. or less.

  Adoption of the above-described configuration in the epoxy resin material according to the present invention can improve the adhesion between the cured product and the metal layer. In particular, when the storage elastic modulus E ′ is less than or equal to the above upper limit, when stress is applied to the interface between the insulating layer and the metal layer, the resin component has good elongation characteristics in the insulating layer, and the stress is relieved. Since the area of a component becomes large, the interface peeling between the insulating layer and the metal layer can be effectively suppressed.

  Examples of the method for setting the storage elastic modulus E ′ to the above value or less include a method using an epoxy resin having a large epoxy equivalent, a method using a curing agent having a large equivalent, and a method using a polymer component such as a thermoplastic resin. .

  Examples of the method for setting the thermal linear expansion coefficient to the above value or less include a method for increasing the blending amount of the inorganic filler, a method for increasing the crosslinking density of the resin, and a method for stacking constituent molecules by intermolecular force.

  The cured product for measuring the storage elastic modulus E ′ and the thermal expansion coefficient is preferably measured using a cured product obtained by thermally curing an epoxy resin material at 190 ° C. for 2 hours.

  The storage elastic modulus E ′ at 250 ° C. measured by the dynamic viscoelasticity measuring apparatus is measured under conditions of a temperature rising rate of 5 ° C./min and a temperature range of 30 to 300 ° C. Examples of the dynamic viscoelasticity measuring apparatus include a viscoelasticity spectrometer (“EXSTAR DMS6100” manufactured by SII Nano Technology).

The thermal expansion coefficient is measured in a tensile load of 2.94 × 10 ⁻² N, a temperature increase rate of 5 ° C./min, and a temperature range of 25 to 150 ° C. Examples of the measurement device for the thermal linear expansion coefficient include a heat / stress / strain measurement device (“EXSTAR TMA / SS6100” manufactured by SII Nanotechnology).

  Conventionally, as a method for lowering the thermal linear expansion coefficient of a cured product, a method of increasing the blending amount of an inorganic filler is generally employed. However, when the blending amount of the inorganic filler is increased, the adhesion between the cured product (insulating layer) and the metal layer (conductor wiring) decreases.

  On the other hand, in this invention, even if there are many compounding quantities of an inorganic filler, even if there are few, the adhesiveness of hardened | cured material and a metal layer can fully be improved. In the present invention, the amount of the inorganic filler may be large or small. From the viewpoint of lowering the thermal linear expansion coefficient of the cured product, it is preferable that the amount of the inorganic filler is large. The epoxy resin material according to the present invention preferably contains an inorganic filler. In this case, the surface roughness of the roughened cured product can be reduced. As a result, for example, when a metal layer is formed on the roughened surface after roughening the surface of the precured product that has been cured of the epoxy resin material, the adhesion between the cured product and the metal layer Can be further increased.

  The epoxy resin material according to the present invention may be a paste or a film. The epoxy resin material according to the present invention may be a resin composition or a B-stage film in which the resin composition is formed into a film. The epoxy resin material according to the present invention is preferably a B-stage film formed into a film.

  Moreover, it is preferable that the epoxy resin material which concerns on this invention is an epoxy resin material used in order to obtain the hardened | cured material roughened.

  Hereinafter, each component contained in the epoxy resin material according to the present invention and details of each component preferably contained will be described.

[Epoxy resin materials]
The epoxy resin contained in the epoxy resin material is not particularly limited. A conventionally well-known epoxy resin can be used as this epoxy resin. The epoxy resin refers to an organic compound having at least one epoxy group. As for the said epoxy resin, only 1 type may be used and 2 or more types may be used together.

  Examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, biphenyl novolac type epoxy resin, biphenol type epoxy resin, naphthalene type epoxy resin, and fluorene type epoxy resin. , Phenol aralkyl type epoxy resin, naphthol aralkyl type epoxy resin, dicyclopentadiene type epoxy resin, anthracene type epoxy resin, epoxy resin having adamantane skeleton, epoxy resin having tricyclodecane skeleton, and epoxy resin having triazine nucleus in skeleton Etc.

  The epoxy resin may be liquid at normal temperature (23 ° C.) or may be solid. The epoxy resin material preferably contains an epoxy resin that is liquid at normal temperature (23 ° C.). In 100% by weight of the total solid content excluding the inorganic filler contained in the epoxy resin material (hereinafter also referred to as total solid content B), the content of the epoxy resin that is liquid at room temperature is preferably 10% by weight or more, More preferably, it is 25% by weight or more, and preferably 80% by weight or less. It is easy to increase content of the inorganic filler in an epoxy resin material as content of the epoxy resin which is liquid at normal temperature is more than the said minimum. “Total solid content B” refers to the sum of the epoxy resin, the curing agent, and the solid content blended as necessary. “Total solid content B” does not include an inorganic filler. “Total solid content B” includes a curing accelerator and a thermoplastic resin described later. “Solid content” refers to a non-volatile component that does not volatilize during molding or heating.

  From the viewpoint of further reducing the surface roughness of the roughened cured product, the epoxy equivalent of the epoxy resin is preferably 90 or more, more preferably 100 or more, preferably 1000 or less, more preferably 800 or less. It is.

  The epoxy resin preferably has a weight average molecular weight of 1000 or less. In this case, it is easy to increase the content of the inorganic filler in the epoxy resin material. Furthermore, even if there is much content of an inorganic filler, the resin composition which is an epoxy resin material with high fluidity | liquidity is obtained. On the other hand, by the combined use of an epoxy resin having a weight average molecular weight of 1000 or less and a thermoplastic resin, it is possible to suppress a decrease in the melt viscosity of the B stage film that is an epoxy resin material. For this reason, when a B stage film is laminated on a board | substrate, an inorganic filler becomes easy to exist uniformly.

[Curing agent]
The curing agent contained in the epoxy resin material is not particularly limited. A conventionally known curing agent can be used as the curing agent. As for the said hardening | curing agent, only 1 type may be used and 2 or more types may be used together.

  As the curing agent, cyanate ester compound (cyanate ester curing agent), phenol compound (phenol curing agent), amine compound (amine curing agent), thiol compound (thiol curing agent), imidazole compound, phosphine compound, acid anhydride, Examples include active ester compounds and dicyandiamide. Especially, from a viewpoint of obtaining the hardened | cured material in which the dimensional change by a heat | fever is still smaller, it is preferable that the said hardening | curing agent is a cyanate ester compound or a phenol compound. The curing agent is preferably a cyanate ester compound, and is preferably a phenol compound. The curing agent preferably has a functional group capable of reacting with the epoxy group of the epoxy resin.

  From the viewpoint of further reducing the surface roughness of the surface of the insulating layer and further increasing the adhesion between the insulating layer and the metal layer, the curing agent is a cyanate ester compound, a phenol compound or an active ester compound. It is preferable. Furthermore, from the viewpoint of imparting better insulation reliability with a curing agent, the curing agent is more preferably a cyanate ester compound.

  By using the cyanate ester compound, the size of the pores formed by the roughening treatment becomes fine, the number of pores increases, and the depth of the pores increases. As a result, the adhesion between the cured product and the insulating layer is further enhanced. Further, by using a cyanate ester compound, a cured product having a smaller dimensional change due to heat can be obtained. Moreover, favorable insulation reliability can be provided to the insulating layer by using a cyanate ester compound. Furthermore, the use of the cyanate ester compound further increases the glass transition temperature of the insulating layer having a high inorganic filler content.

  The cyanate ester compound is not particularly limited. As the cyanate ester compound, a conventionally known cyanate ester compound can be used. As for the said cyanate ester compound, only 1 type may be used and 2 or more types may be used together.

  Examples of the cyanate ester compound include novolac-type cyanate ester resins, bisphenol-type cyanate ester resins, and prepolymers in which these are partially trimerized. As said novolak-type cyanate ester resin, a phenol novolak-type cyanate ester resin, an alkylphenol-type cyanate ester resin, etc. are mentioned. Examples of the bisphenol type cyanate ester resin include bisphenol A type cyanate ester resin, bisphenol E type cyanate ester resin, and tetramethylbisphenol F type cyanate ester resin.

  From the viewpoint of further reducing the thermal linear expansion coefficient of the cured product and further improving the adhesion between the cured product and the metal layer, the cyanate ester compound as the curing agent is preferably a bisphenol type cyanate ester compound.

  Commercially available products of the above-mentioned cyanate ester compounds include phenol novolac type cyanate ester resins (Lonza Japan "PT-30" and "PT-60"), and prepolymers (Lonza Japan) in which bisphenol type cyanate ester resins are trimerized. "BA-230S", "BA-3000S", "BTP-1000S", and "BTP-6020S") manufactured by the company.

  The cyanate ester compound preferably has a weight average molecular weight of 3000 or less. In this case, the content of the inorganic filler in the resin composition can be increased, and a resin composition having high fluidity can be obtained even if the content of the inorganic filler is large.

  The “weight average molecular weight” indicates a weight average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC).

  By using the phenol compound, the glass transition temperature of the insulating layer is further increased. In addition, the use of the phenol compound increases the strength and heat resistance of the insulating layer and further increases the adhesion between the insulating layer and the metal layer. Further, the use of the phenol compound increases the smoothness of the surface of the insulating layer. The phenol compound is not particularly limited. A conventionally well-known phenol compound can be used as this phenol compound. As for the said phenol compound, only 1 type may be used and 2 or more types may be used together.

  Examples of the phenol compound include biphenyl type phenol curing agents and naphthol type phenol curing agents.

  Commercially available products of the above-mentioned phenol compounds include biphenyl type phenol curing agents (“KAYAHARDGPH-103” manufactured by Nippon Kayaku Co., Ltd. and “MEH7851” manufactured by Meiwa Kasei Co., Ltd.), and naphthol type curing agents (“SN485” manufactured by Tohto Kasei Co., Ltd., Japan) “KAYAHARDNHN”) manufactured by Kayaku Co., Ltd.

  From the viewpoint of further reducing the surface roughness of the insulating layer, the phenol compound preferably has two or more phenolic hydroxyl groups.

  From the viewpoint of further reducing the surface roughness of the surface of the insulating layer, forming finer wiring on the surface of the insulating layer, and providing good insulation reliability with the curing agent, the curing agent is equivalent to It is preferable to contain the hardening | curing agent whose is 250 or less. When the said hardening | curing agent is a cyanate ester compound, the equivalent in the said hardening | curing agent shows cyanate ester group equivalent. When the said hardening | curing agent is a phenol compound, the equivalent in the said hardening | curing agent shows a phenolic hydroxyl group equivalent.

  The content of the curing agent having an equivalent weight of 250 or less in 100% by weight of the entire curing agent is preferably 30% by weight or more, more preferably 50% by weight or more. The total amount of the curing agent may be a curing agent having an equivalent weight of 250 or less. When the content of the curing agent having an equivalent weight of 250 or less is not less than the above lower limit, the surface roughness of the surface of the insulating layer is further reduced, and finer wiring can be formed on the surface of the insulating layer. Furthermore, the glass transition temperature of an insulating layer becomes still higher that content of the hardening | curing agent whose equivalent is 250 or less is more than the said minimum.

  The weight average molecular weight of the phenol compound is preferably 100 or more, more preferably 500 or more, preferably 50000 or less, more preferably 20000 or less. A B stage film can be easily obtained as the weight average molecular weight of the said hardening | curing agent is more than the said minimum, and a B stage film does not become weak easily. When the weight average molecular weight of the phenol compound is not more than the above upper limit, the glass transition temperature of the cured product is further increased, and the heat resistance of the cured product is further increased.

  The “weight average molecular weight” indicates a weight average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC).

  The compounding ratio of the epoxy resin and the curing agent is not particularly limited. The compounding ratio of the epoxy resin and the curing agent is appropriately determined depending on the types of the epoxy resin and the curing agent. The equivalent ratio of the epoxy resin and the curing agent (epoxy equivalent: equivalent of the curing agent) is preferably 1: 0.25 to 1: 2, and preferably 1: 0.3 to 1: 1.5. It is more preferable. When the equivalent ratio satisfies the above range, the adhesion between the insulating layer and the metal layer is further enhanced.

[Inorganic filler]
The inorganic filler contained in the epoxy resin material is not particularly limited. As the inorganic filler, conventionally known inorganic fillers can be used. As for the said inorganic filler, only 1 type may be used respectively and 2 or more types may be used together.

  Examples of the inorganic filler include silica, talc, clay, mica, hydrotalcite, alumina, magnesium oxide, aluminum hydroxide, aluminum nitride, and boron nitride.

  From the viewpoint of further reducing the surface roughness of the roughened cured product surface, forming finer wiring on the cured product surface, and imparting good insulation reliability to the cured product, The inorganic filler is preferably silica or alumina, more preferably silica, and still more preferably fused silica. By using silica, the coefficient of thermal expansion of the cured product is further reduced, and the surface roughness of the surface of the cured product that has been roughened is effectively reduced. The shape of silica is preferably substantially spherical.

  The average particle size of the inorganic filler is preferably 1 nm or more, more preferably 10 nm or more, further preferably 50 nm or more, particularly preferably 150 nm or more, preferably 20 μm or less, more preferably 10 μm or less, still more preferably 5 μm or less, particularly Preferably it is 1 micrometer or less. When the average particle size of the inorganic filler is not less than the above lower limit and not more than the above upper limit, the size of the holes formed by the roughening treatment becomes fine, the number of holes increases, and the depth of the holes is deep. Become. As a result, the adhesion between the cured product and the metal layer is further enhanced.

  A median diameter (d50) value of 50% is employed as the average particle diameter of the inorganic filler. The average particle size can be measured using a laser diffraction / scattering particle size distribution measuring apparatus.

  The inorganic filler is preferably spherical and more preferably spherical silica. In this case, the surface roughness of the surface of the insulating layer is effectively reduced, and the adhesion between the cured product and the metal layer is effectively increased. The inorganic filler is preferably surface-treated, and more preferably surface-treated with a coupling agent. As a result, the surface roughness of the roughened insulating layer is further reduced, finer wiring can be formed on the surface of the insulating layer, and the insulating layer has better inter-wiring insulation reliability and interlayer insulation. Reliability can be imparted.

  When the inorganic filler is spherical, the aspect ratio of the inorganic filler is preferably 2 or less, more preferably 1.5 or less.

  The content of the inorganic filler is not particularly limited. The content of the inorganic filler is preferably 25% by weight or more, more preferably 30% in 100% by weight of the total solid content (hereinafter sometimes abbreviated as total solid content A) contained in the epoxy resin material. % By weight or more, more preferably 40% by weight or more, particularly preferably 50% by weight or more, preferably 85% by weight or less, more preferably 80% by weight or less, still more preferably 75% by weight or less. When the content of the inorganic filler is not less than the above lower limit and not more than the above upper limit, the surface roughness of the roughened cured product is further reduced, and finer wiring is formed on the surface of the cured product. And the adhesion between the cured product and the metal layer is further enhanced. Furthermore, the thermal linear expansion coefficient of hardened | cured material becomes still lower that content of the said inorganic filler is more than the said minimum and below the said upper limit. “Total solid content A” refers to the sum of the epoxy resin, the curing agent, the inorganic filler, and the solid content blended as necessary. “Total solid content A” includes a curing accelerator and a thermoplastic resin described later. “Solid content” refers to a non-volatile component that does not volatilize during molding or heating.

[Thermoplastic resin]
The epoxy resin material according to the present invention preferably contains a thermoplastic resin. The thermoplastic resin is not particularly limited. A conventionally known thermoplastic resin can be used as the thermoplastic resin. As for the said thermoplastic resin, only 1 type may be used and 2 or more types may be used together.

  Examples of the thermoplastic resin include phenoxy resins, polyvinyl acetal resins, modified polyphenylene ether resins, rubber components, and organic fillers. The thermoplastic resin is particularly preferably a phenoxy resin. By using the phenoxy resin, the melt viscosity can be adjusted, so that the dispersibility of the inorganic filler is improved, and the B stage film is difficult to wet and spread in an unintended region during the curing process. Moreover, the deterioration of the embedding property with respect to the hole or the unevenness | corrugation of the circuit board of a resin composition or a B stage film and the nonuniformity of an inorganic filler can be suppressed by making the compounding quantity of a phenoxy resin into a predetermined range.

  Examples of the phenoxy resin include phenoxy resins having a skeleton such as a bisphenol A skeleton, a bisphenol F skeleton, a bisphenol S skeleton, a biphenyl skeleton, a novolac skeleton, a naphthalene skeleton, and an imide skeleton.

  From the viewpoint of further reducing the thermal linear expansion coefficient of the cured product and further improving the adhesion between the cured product and the metal layer, the thermoplastic resin is preferably a modified polyphenylene ether resin. Since the modified polyphenylene ether resin has no or few reactive groups in the skeleton, the molecular weight between crosslinking points can be increased in the cured product, and the adhesion between the cured product and the metal layer can be reduced by reducing the crosslinking density. Becomes higher.

  The thermoplastic resin preferably has a weight average molecular weight of 3000 or more, preferably 100,000 or less. The weight average molecular weight indicates a weight average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC).

  Examples of commercially available phenoxy resins include “YP50”, “YP55” and “YP70” manufactured by Toto Kasei Co., Ltd., and “1256B40”, “4250”, “4256H40”, “4275” manufactured by Mitsubishi Chemical Corporation, Examples thereof include “YX6954BH30” and “YX8100BH30”.

  The content of the thermoplastic resin is not particularly limited. Of the total solid content B of 100% by weight, the content of the thermoplastic resin (when the thermoplastic resin is a phenoxy resin, the content of the phenoxy resin) is preferably 1% by weight or more, more preferably 5% by weight or more. , Preferably 30% by weight or less, more preferably 20% by weight or less, and even more preferably 15% by weight or less. When the content of the thermoplastic resin is not less than the above lower limit and not more than the above upper limit, the thermal linear expansion coefficient of the cured product is further lowered. Moreover, the embedding property with respect to the hole or unevenness | corrugation of the circuit board of an epoxy resin material becomes favorable. When the content of the thermoplastic resin is not less than the above lower limit, the film-forming property is enhanced, and an even better B-stage film is obtained. When the content of the thermoplastic resin is not more than the above upper limit, the surface roughness of the roughened cured product is further reduced, and the adhesion between the cured product and the metal layer is further enhanced.

[Curing accelerator]
The epoxy resin material preferably contains a curing accelerator. By using the curing accelerator, the curing rate is further increased. By rapidly curing the epoxy resin material, the cross-linked structure of the cured product can be made uniform, the number of unreacted functional groups is reduced, and as a result, the cross-linking density is increased. The said hardening accelerator is not specifically limited. Conventionally known curing accelerators can be used as the curing accelerator. As for the said hardening accelerator, only 1 type may be used and 2 or more types may be used together.

  Examples of the curing accelerator include imidazole compounds, phosphorus compounds, amine compounds, and organometallic compounds.

  Examples of the imidazole compound include 2-undecylimidazole, 2-heptadecylimidazole, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl- 2-methylimidazole, 1-benzyl-2-phenylimidazole, 1,2-dimethylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-un Decylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6- [2 ′ -Methyl Midazolyl- (1 ′)]-ethyl-s-triazine, 2,4-diamino-6- [2′-undecylimidazolyl- (1 ′)]-ethyl-s-triazine, 2,4-diamino-6 [2′-Ethyl-4′-methylimidazolyl- (1 ′)]-ethyl-s-triazine, 2,4-diamino-6- [2′-methylimidazolyl- (1 ′)]-ethyl-s-triazine Isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-methylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole and 2-phenyl-4-methyl-5-dihydroxymethylimidazole Can be mentioned.

  Examples of the phosphorus compound include triphenylphosphine.

  Examples of the amine compound include diethylamine, triethylamine, diethylenetetramine, triethylenetetramine and 4,4-dimethylaminopyridine.

  Examples of the organometallic compound include zinc naphthenate, cobalt naphthenate, tin octylate, cobalt octylate, bisacetylacetonate cobalt (II), and trisacetylacetonate cobalt (III).

  From the viewpoint of increasing the insulation reliability of the cured product, the curing accelerator is particularly preferably an imidazole compound. By using an imidazole compound, an epoxy resin material having a curing exothermic peak top measured by a differential scanning calorimeter within a temperature range of 130 ° C. or higher and 180 ° C. or lower and a half-value width of the exothermic peak of 20 ° C. or lower is obtained. Becomes easier.

  The content of the curing accelerator is not particularly limited. From the viewpoint of efficiently curing the epoxy resin material, the content of the curing accelerator in the total solid content B of 100% by weight is preferably 0.01% by weight or more, and preferably 3% by weight or less.

[Other ingredients]
For the purpose of improving impact resistance, heat resistance, resin compatibility and workability, epoxy resin materials include coupling agents, colorants, antioxidants, UV degradation inhibitors, antifoaming agents, and thickeners. A thixotropic agent and other resins other than those mentioned above may be added.

  Examples of the coupling agent include silane coupling agents, titanium coupling agents, and aluminum coupling agents. Examples of the silane coupling agent include vinyl silane, amino silane, imidazole silane, and epoxy silane.

  The content of the coupling agent is not particularly limited. In the total solid content B of 100% by weight, the content of the coupling agent is preferably 0.01% by weight or more and 5% by weight or less.

  Examples of the other resin include polyphenylene ether resin, divinyl benzyl ether resin, polyarylate resin, diallyl phthalate resin, polyimide resin, benzoxazine resin, benzoxazole resin, bismaleimide resin, and acrylate resin.

(B-stage film epoxy resin material)
As a method for forming the resin composition into a film, for example, an extrusion molding method is used in which the resin composition is melt-kneaded using an extruder, extruded, and then formed into a film using a T-die or a circular die. Examples thereof include a casting molding method in which the resin composition is dissolved or dispersed in a solvent such as an organic solvent and then cast into a film, and other conventionally known film molding methods. Of these, the extrusion molding method or the casting molding method is preferable because the thickness can be reduced. The film includes a sheet.

  A B-stage film can be obtained by forming the resin composition into a film and drying it by heating at 90 to 200 ° C. for 10 to 180 seconds to such an extent that curing by heat does not proceed excessively.

  The film-like resin composition that can be obtained by the drying process as described above is referred to as a B-stage film.

  The B-stage film is a semi-cured product in a semi-cured state. The semi-cured product is not completely cured and curing can proceed further.

  The said resin composition can be used suitably in order to form a laminated film provided with a base material and the B stage film laminated | stacked on one surface of this base material. A B-stage film of a laminated film is formed from the resin composition.

  Examples of the base material of the laminated film include polyester resin films such as polyethylene terephthalate film and polybutylene terephthalate film, olefin resin films such as polyethylene film and polypropylene film, polyimide resin film, metal foil such as copper foil and aluminum foil, and the like. Can be mentioned. The surface of the base material may be subjected to a release treatment as necessary.

  When the epoxy resin material is used as an insulating layer of a circuit, the thickness of the layer formed of the epoxy resin material is preferably equal to or greater than the thickness of the conductor layer that forms the circuit. The thickness of the layer formed of the epoxy resin material is preferably 5 μm or more, and preferably 200 μm or less.

(Printed wiring board)
The said epoxy resin material is used suitably in order to form an insulating layer in a printed wiring board.

  The printed wiring board can be obtained, for example, by using a B stage film formed of the resin composition and heat-pressing the B stage film on a circuit board or the like.

  A metal foil can be laminated on one side or both sides of the B-stage film. The method for laminating the B-stage film and the metal foil is not particularly limited, and a known method can be used. For example, the B-stage film can be laminated on the metal foil using an apparatus such as a parallel plate press or a roll laminator while applying pressure while heating or without heating.

(Copper-clad laminate and multilayer board)
The said epoxy resin material is used suitably in order to obtain a copper clad laminated board. An example of the copper-clad laminate is a copper-clad laminate comprising a copper foil and a B stage film laminated on one surface of the copper foil. The copper-clad laminate B-stage film is formed of the epoxy resin material according to the present invention.

  The thickness of the copper foil of the copper-clad laminate is not particularly limited. The thickness of the copper foil is preferably in the range of 1 to 50 μm. Moreover, in order to raise the adhesive strength of the hardened | cured material layer which hardened the epoxy resin material, and copper foil, it is preferable that the said copper foil has a fine unevenness | corrugation on the surface. The method for forming the unevenness is not particularly limited. Examples of the method for forming the unevenness include a formation method by treatment using a known chemical solution.

  Moreover, the epoxy resin material according to the present invention is suitably used for obtaining a multilayer substrate. As an example of the multilayer substrate, there is a multilayer substrate including a circuit board and a cured product layer laminated on the surface of the circuit board. The cured product layer of the multilayer substrate is formed by curing the epoxy resin material. It is preferable that the said hardened | cured material layer is laminated | stacked on the surface in which the circuit of the circuit board was provided. Part of the cured product layer is preferably embedded between the circuits.

  In the multilayer substrate, it is more preferable that the surface of the cured product layer opposite to the surface on which the circuit substrate is laminated is roughened. The roughening method can be any conventionally known roughening method and is not particularly limited. The surface of the cured product layer may be swelled before the roughening treatment.

  Moreover, it is preferable that the said multilayer substrate is further equipped with the metal layer laminated | stacked on the surface by which the roughening process of the said hardened | cured material layer was carried out. The metal layer is preferably a copper layer, and is preferably a copper plating layer.

  Further, as another example of the multilayer board, a circuit board, a cured product layer laminated on the surface of the circuit board, and a surface of the cured product layer opposite to the surface on which the circuit board is laminated are provided. A multilayer board | substrate provided with the laminated copper foil is mentioned. The cured product layer and the copper foil are formed by curing the B-stage film using a copper-clad laminate comprising a copper foil and a B-stage film laminated on one surface of the copper foil. Preferably it is. Furthermore, it is preferable that the copper foil is etched and is a copper circuit.

  Another example of the multilayer substrate is a multilayer substrate including a circuit board and a plurality of cured product layers stacked on the surface of the circuit board. At least one of the plurality of cured product layers is formed by curing the epoxy resin material. It is preferable that the multilayer substrate further includes a circuit laminated on at least one surface of the cured product layer formed by curing the epoxy resin material.

  FIG. 1 is a partially cutaway front sectional view schematically showing a multilayer substrate using an epoxy resin material according to an embodiment of the present invention.

  In the multilayer substrate 11 shown in FIG. 1, a plurality of cured product layers 13 to 16 are laminated on the upper surface 12 a of the circuit substrate 12. The cured product layers 13 to 16 are insulating layers. A metal layer 17 is formed in a partial region of the upper surface 12 a of the circuit board 12. Among the plurality of cured product layers 13 to 16, the cured product layers 13 to 15 other than the cured product layer 16 located on the outer surface opposite to the circuit board 12 side include a metal layer in a partial region of the upper surface. 17 is formed. The metal layer 17 is a circuit. Metal layers 17 are respectively arranged between the circuit board 12 and the cured product layer 13 and between the laminated cured product layers 13 to 16. The lower metal layer 17 and the upper metal layer 17 are connected to each other by at least one of via hole connection and through hole connection (not shown).

  In the multilayer substrate 11, the cured product layers 13 to 16 are formed by curing the epoxy resin material according to the present invention. In the present embodiment, since the surfaces of the cured product layers 13 to 16 are roughened, fine holes (not shown) are formed on the surfaces of the cured product layers 13 to 16. Further, the metal layer 17 reaches the inside of the fine hole. Moreover, in the multilayer substrate 11, the width direction dimension (L) of the metal layer 17 and the width direction dimension (S) of the part in which the metal layer 17 is not formed can be made small. In the multilayer substrate 11, good insulation reliability is imparted between an upper metal layer and a lower metal layer that are not connected by via-hole connection and through-hole connection (not shown).

(Roughening treatment and swelling treatment)
The epoxy resin material according to the present invention is preferably used for obtaining a cured product to be roughened. The cured product includes a precured product that can be further cured.

  In order to form fine irregularities on the surface of the precured material obtained by precuring the epoxy resin material according to the present invention, the precured material is preferably subjected to a roughening treatment. Prior to the roughening treatment, the precured product is preferably subjected to a swelling treatment. The cured product is preferably subjected to a swelling treatment after preliminary curing and before the roughening treatment, and is further cured after the roughening treatment. However, the pre-cured product may not necessarily be subjected to the swelling treatment.

  As a method for the swelling treatment, for example, a method of treating a precured product with an aqueous solution or an organic solvent dispersion solution of a compound mainly composed of ethylene glycol or the like is used. The swelling liquid used for the swelling treatment generally contains an alkali as a pH adjuster or the like. The swelling liquid preferably contains sodium hydroxide. Specifically, for example, the swelling treatment is performed by treating a precured product with a 40 wt% ethylene glycol aqueous solution at a treatment temperature of 30 to 85 ° C. for 1 to 30 minutes. The swelling treatment temperature is preferably in the range of 50 to 85 ° C. When the temperature of the swelling treatment is too low, it takes a long time for the swelling treatment, and the roughened adhesive strength between the cured product and the metal layer tends to be low.

  For the roughening treatment, for example, a chemical oxidizing agent such as a manganese compound, a chromium compound, or a persulfuric acid compound is used. These chemical oxidizers are used as an aqueous solution or an organic solvent dispersion after water or an organic solvent is added. The roughening liquid used for the roughening treatment generally contains an alkali as a pH adjuster or the like. The roughening solution preferably contains sodium hydroxide.

  Examples of the manganese compound include potassium permanganate and sodium permanganate. Examples of the chromium compound include potassium dichromate and anhydrous potassium chromate. Examples of the persulfate compound include sodium persulfate, potassium persulfate, and ammonium persulfate.

  The method for the roughening treatment is not particularly limited. As a method of the said roughening process, 30-90 g / L permanganic acid or a permanganate solution and 30-90 g / L sodium hydroxide solution are used, for example, process temperature 30-85 degreeC and 1-30 minutes. A method of treating a precured product once or twice under conditions is preferable. It is preferable that the temperature of the said roughening process exists in the range of 50-85 degreeC.

  The arithmetic average roughness Ra of the surface of the roughened cured product is preferably 50 nm or more, and preferably 350 nm or less. In this case, the adhesion between the cured product and the metal layer is further enhanced, and further finer wiring can be formed on the surface of the cured product layer.

Moreover, a through-hole may be formed in the precured material or hardened | cured material obtained by precuring the epoxy resin material which concerns on this invention. In the multilayer substrate or the like, a via or a through hole is formed as a through hole. For example, the via can be formed by irradiation with a laser such as a CO ₂ laser. The diameter of the via is not particularly limited, but is about 60 to 80 μm. Due to the formation of the through hole, a smear that is a resin residue derived from the resin component contained in the cured product layer is often formed at the bottom of the via.

  In order to remove the smear, the surface of the cured product layer is preferably desmeared. The surface of the cured product is roughened by desmear treatment. By using the epoxy resin material according to the present invention, the surface roughness of the surface of the cured product subjected to the desmear treatment is reduced. The desmear process may also serve as the roughening process.

  For the desmear treatment, for example, a chemical oxidant such as a manganese compound, a chromium compound, or a persulfate compound is used in the same manner as the roughening treatment described above. These chemical oxidizers are used as an aqueous solution or an organic solvent dispersion after water or an organic solvent is added. The desmear treatment liquid used for the desmear treatment generally contains an alkali. The desmear treatment liquid preferably contains sodium hydroxide.

  The method for the desmear treatment is not particularly limited. As a method for the desmear treatment, for example, using a 30 to 90 g / L permanganate or permanganate solution and a 30 to 90 g / L sodium hydroxide solution, a treatment temperature of 30 to 85 ° C. and a condition of 1 to 30 minutes A method of treating a precured product or a cured product once or twice is preferable. It is preferable that the temperature of the said desmear process exists in the range of 50-85 degreeC.

  Hereinafter, the present invention will be specifically described by giving examples and comparative examples. The present invention is not limited to the following examples.

(Epoxy resin)
Bisphenol A type epoxy resin (“828EL” manufactured by Mitsubishi Chemical Corporation)
Biphenyl skeleton-containing epoxy resin (“NC-3000H” manufactured by Nippon Kayaku Co., Ltd.)
Epoxy resin containing dicyclopentadiene skeleton (“XD-1000” manufactured by Nippon Kayaku Co., Ltd.)

(Cyanate ester resin)
Cyanate ester resin solution 1 (Prepolymer solution of bisphenol A type dicyanate, “BA-230S” manufactured by Lonza Japan, cyanate ester resin (solid content) 75 wt%, solvent (methyl ethyl ketone) 25 wt%)
Cyanate ester resin solution 2 (Prepolymer solution of bisphenol A type dicyanate, “BTP-6020S” manufactured by Lonza Japan Co., Ltd., cyanate ester resin (solid content) 65 wt%, solvent (methyl ethyl ketone 30 wt%, dimethylformamide 5 wt%) 35 weight%)

(Phenolic resin)
Biphenyl skeleton-containing phenol resin (“MEH7851-H” manufactured by Meiwa Kasei Co., Ltd.)

(Active ester curing agent)
Active ester curing agent (“HPC-8000” manufactured by DIC)

(Thermoplastic resin)
Biphenyl skeleton-containing phenoxy resin solution (Mitsubishi Chemical "YX6954BH30", biphenyl skeleton-containing phenoxy resin (solid content) 30 wt%, solvent (mixed solvent of methyl ethyl ketone and cyclohexanone) 70 wt%)
Modified polyphenylene ether resin solution (solution of “Xylon S202A” manufactured by Asahi Kasei Co., Ltd. dissolved in toluene to 5% by weight)

(Curing accelerator)
Imidazole Compound A (2-Phenyl-4-methylimidazole, “2P4MZ” manufactured by Shikoku Chemicals)
Imidazole compound B (2-ethyl-4methylimidazole, “2E4MZ” manufactured by Shikoku Kasei Kogyo Co., Ltd.)

(Inorganic filler)
Inorganic filler A (silica (“SO-C1” manufactured by Admatechs, average particle size of 0.25 μm) is epoxy silane (3-glycidoxypropyltrimethoxysilane), “KBM-403” manufactured by Shin-Etsu Chemical Co., Ltd. Surface treatment)
Inorganic filler B (silica (“SO-C2” manufactured by Admatechs, average particle size 0.50 μm) is epoxysilane (3-glycidoxypropyltrimethoxysilane, “KBM-403” manufactured by Shin-Etsu Chemical Co., Ltd.)) Surface treatment)

(solvent)
Methyl ethyl ketone

Example 1
100 parts by weight of methyl ethyl ketone, 100 parts by weight of inorganic filler A (silica (“Ad-Tex” “SO-C1”)), 25 parts by weight of bisphenol A type epoxy resin (“828EL” manufactured by Mitsubishi Chemical), and biphenyl skeleton 5 parts by weight of an epoxy resin (“NC-3000H” manufactured by Nippon Kayaku Co., Ltd.), 15 parts by weight (11.25 parts by weight in solid content) of cyanate ester resin solution 1 (“BA-230S” manufactured by Lonza Japan), 25 parts by weight (7.5 parts by weight of solid content) of biphenyl skeleton-containing phenoxy resin solution (“YX6954BH30” manufactured by Mitsubishi Chemical Corporation) and imidazole compound A (2-phenyl-4-methylimidazole, “2P4MZ manufactured by Shikoku Chemicals Co., Ltd.) ]) 0.6 part by weight was added and stirred at room temperature to obtain a resin composition varnish.

  A release-treated transparent polyethylene terephthalate (PET) film (“PET5011 550” manufactured by Lintec Corporation, thickness 50 μm) was prepared. The obtained resin composition varnish was applied onto the surface of the PET film subjected to the mold release treatment using an applicator so that the thickness after drying was 40 μm. Next, it was dried in a gear oven at 100 ° C. for 2 minutes to prepare a laminated film of an uncured resin sheet (B stage film) of 200 mm long × 200 mm wide × 40 μm thick and a PET film.

(Examples 2 to 7 and Comparative Examples 1 and 2)
A laminated film was produced in the same manner as in Example 1 except that the types and blending amounts of the blending components were changed as shown in Table 1 below.

(Evaluation)
(1) Measurement of peel strength A sample for measuring peel strength was prepared as follows.

Laminate surface treatment:
Both surfaces of a glass epoxy substrate (“CS-3665” manufactured by Risho Kogyo Co., Ltd.) on which an inner layer circuit has been formed by etching are immersed in a copper surface roughening agent (“MEC Etch Bond CZ-8100” manufactured by MEC) to immerse the copper surface. Roughening treatment was performed.

Lamination of laminated film:
The obtained laminated film is set on both surfaces of the glass epoxy substrate from the uncured side of the resin sheet, and the glass epoxy substrate is used with a diaphragm vacuum laminator (“MVLP-500” manufactured by Meiki Seisakusho Co., Ltd.). Laminated on both sides. Lamination was performed by reducing the pressure for 20 seconds to a pressure of 13 hPa or less, and then pressing for 20 seconds at 100 ° C. and a pressure of 0.8 MPa.

Curing of resin sheet:
The PET film was peeled from the laminated film laminated, and then the resin sheet was cured under the curing conditions of 170 ° C. and 60 minutes to obtain a laminated sample.

Swelling treatment:
The above laminated sample is put in a swelling solution at 60 ° C. (an aqueous solution composed of “Swelling Dip Securigant P” manufactured by Atotech Japan Co., Ltd.) and “sodium hydroxide” manufactured by Wako Pure Chemical Industries, Ltd., and the swelling temperature is 60 ° C. for 10 minutes. Rocked. Thereafter, it was washed with pure water.

Roughening treatment (permanganate treatment):
The above-mentioned layered sample that has been swollen is placed in a 80 ° C. sodium permanganate roughening aqueous solution (“Concentrate Compact CP” manufactured by Atotech Japan, “Sodium hydroxide” manufactured by Wako Pure Chemical Industries, Ltd.). Rock at 20 ° C. for 20 minutes. Then, after washing | cleaning for 10 minutes with a 40 degreeC washing | cleaning liquid ("Reduction securigant P" by the Atotech Japan company, "Sulfuric acid" by Wako Pure Chemical Industries, Ltd.), it wash | cleaned further with the pure water. In this way, a roughened cured product was formed on the glass epoxy substrate on which the inner layer circuit was formed by etching.

Electroless plating treatment:
The surface of the roughened cured product was treated with a 60 ° C. alkali cleaner (“Cleaner Securigant 902” manufactured by Atotech Japan) for 5 minutes and degreased and washed. After washing, the cured product was treated with a 25 ° C. pre-dip solution (“Pre-Dip Neogant B” manufactured by Atotech Japan) for 2 minutes. Thereafter, the cured product was treated with an activator solution at 40 ° C. (“Activator Neo Gantt 834” manufactured by Atotech Japan) for 5 minutes to attach a palladium catalyst. Next, the cured product was treated with a reducing solution at 30 ° C. (“Reducer Neogant WA” manufactured by Atotech Japan) for 5 minutes.

  Next, the cured product is put into a chemical copper solution (all manufactured by Atotech Japan “Basic Print Gantt MSK-DK”, “Copper Print Gantt MSK”, “Stabilizer Print Gantt MSK”, “Reducer Cu”). Was carried out until the plating thickness reached about 0.5 μm. After the electroless plating, annealing was performed at a temperature of 120 ° C. for 30 minutes in order to remove the remaining hydrogen gas. All the steps up to the electroless plating step were performed with a treatment liquid of 2 L on a beaker scale and while the cured product was swung.

Next, electrolytic plating was performed on the cured product that had been subjected to electroless plating until the plating thickness reached 25 μm. As an electrolytic copper plating, a copper sulfate solution (“copper sulfate pentahydrate” manufactured by Wako Pure Chemical Industries, Ltd., “sulfuric acid” manufactured by Wako Pure Chemical Industries, Ltd., “basic leveler kaparaside HL” manufactured by Atotech Japan Co., Ltd. Capalaside GS ") was used to conduct electroplating until a current of 0.6 A / cm ² was passed and the plating thickness was about 25 µm. After the copper plating treatment, the cured product was heated at 190 ° C. for 2 hours to further cure the cured product. Thus, the hardened | cured material with which the copper plating layer was laminated | stacked on the upper surface was obtained.

  In the cured product obtained by laminating the obtained copper plating layer, a 10 mm wide cutout was made on the surface of the copper plating layer. Thereafter, the peel strength between the cured product and the copper plating layer was measured using a tensile tester (“AG-5000B” manufactured by Shimadzu Corporation) under the condition of a crosshead speed of 5 mm / min.

(2) Evaluation of coefficient of thermal expansion (CTE) The PET film was peeled from the obtained laminated film, and the uncured resin sheet was heated in a gear oven at 190 ° C. for 2 hours to obtain a cured resin sheet. .

The obtained cured product was cut into a size of 3 mm × 25 mm. Using a heat / stress / strain measuring device ("EXSTAR TMA / SS6100" manufactured by SII Nano Technology), it was cut under the conditions of a tensile load of 2.94 × 10 ^-2 N and a heating rate of 5 ° C / min. The average linear expansion coefficient up to 25 to 150 ° C. of the cured product was measured, and the thermal linear expansion coefficient was evaluated.

(3) Evaluation of storage elastic modulus E ′ by dynamic viscoelasticity measuring device (DMA) The PET film is peeled off from the obtained laminated film, and the uncured resin sheet is heated in a gear oven at 190 ° C. for 2 hours. A cured resin sheet was obtained.

  The obtained cured product was cut into a size of 3 mm × 25 mm. Using a viscoelasticity spectrometer ("EXSTAR DMS6100" manufactured by SII Nanotechnology Inc.), measurement of the cured product cut in a temperature range of 30 to 300 ° C was performed at a temperature rising rate of 5 ° C / min. The value of the storage elastic modulus E ′ at 250 ° C. was evaluated.

  The results are shown in Table 1 below.

DESCRIPTION OF SYMBOLS 11 ... Multilayer substrate 12 ... Circuit board 12a ... Upper surface 13-16 ... Hardened | cured material layer 17 ... Metal layer (wiring)

Claims (4)

Including an epoxy resin, a curing agent, and an inorganic filler,
The storage elastic modulus E ′ at 250 ° C. measured using a dynamic viscoelasticity measuring device of the cured product after thermosetting is 2.0 × 10 ⁸ Pa or less,
The epoxy resin material whose thermal linear expansion coefficient in 25-150 degreeC of the hardened | cured material after thermosetting is 30 ppm / degrees C or less.   The epoxy resin material according to claim 1, further comprising a thermoplastic resin.   The epoxy resin material according to claim 1 or 2, which is a B-stage film formed into a film shape. A circuit board;
A cured product layer disposed on the surface of the circuit board,
The multilayer substrate in which the said hardened | cured material layer is formed by hardening the epoxy resin material of any one of Claims 1-3.

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