JP5195454B2 - Resin composition - Google Patents

Description

  The present invention relates to a resin composition suitable for forming an insulating layer (especially an interlayer insulating layer) of a circuit board such as a multilayer printed wiring board, an insulating resin sheet such as an adhesive film or prepreg obtained from the resin composition, and the resin The present invention relates to a circuit board on which an insulating layer is formed of a cured product of the composition.

  In recent years, with the miniaturization and high performance of electronic devices, circuit boards are required to have fine wiring and further lower the thermal expansion coefficient. As means for reducing the thermal expansion of the insulating material, a method of increasing the filling of an inorganic filler such as silica is known. As means for highly filling silica in a resin composition, a method of surface-treating silica with various coupling agents is known. For example, Patent Document 1 discloses a method for highly filling a surface of a metal oxide powder represented by silica with a silazane compound and a silane coupling agent in an epoxy resin composition for semiconductor encapsulation. Has been. However, in a resin composition used as an interlayer insulating material such as a multilayer circuit board, a conductor layer is formed on the surface of the insulating layer after the formation of the insulating layer, but the resin composition is highly filled with an inorganic filler. Is used, it tends to be difficult to form a conductor layer with excellent peel strength, and when the inorganic filler is excessively dropped, it is disadvantageous for fine wiring due to non-uniform surface roughness of the insulating layer. (For example, an anchor caused by dropping of coarse particles causes a short circuit).

  In addition, as a material for forming the insulating layer of the circuit board, a fiber base material is impregnated with an adhesive film or a resin composition varnish formed by applying and drying a resin composition varnish on a support and drying. A sheet-like insulating material such as a prepreg (hereinafter referred to as “insulating resin sheet”) is generally used. Since such an insulating resin sheet is handled as a sheet-like member, an appropriate melting property for laminating is required. However, due to the high filling of the inorganic filler, the meltability and fluidity of the insulating resin sheet are remarkably lowered and the moldability is poor, which is disadvantageous for resin embedding in a fine wiring region.

JP 2004-59380 A

  This invention is made | formed in view of the above situations, The subject which it is going to solve can be used suitably for the insulating layer formation of a circuit board, and uses it in the form of an insulating resin sheet especially. Resin composition and insulation capable of forming a conductor layer having excellent peelability, low thermal expansion coefficient, and high peel strength even if the surface roughness of the insulating layer obtained by curing it is low It is to provide a resin sheet.

  As a result of intensive studies to solve the above problems, the present inventors used an inorganic filler surface-treated with a silazane compound and then surface-treated with a silane coupling agent as an inorganic filler, and further, a phenoxy resin and When polyvinyl acetal resin is used and these are combined in a specific epoxy resin composition and blended in a large amount, it has good film formability (especially laminating properties and The insulating layer after lamination can be formed into an insulating resin sheet having a good flatness), and further, a conductive layer having a high peel strength can be formed on the insulating layer obtained by curing it, and after the roughening treatment The inventors have found that the conductor layer has a high peel strength even when the surface has a relatively low roughness, and have completed the present invention. That is, the present invention includes the following contents.

(1) (A) polyfunctional epoxy resin, (B) curing agent, (C) phenoxy resin and / or polyvinyl acetal resin, and (D) inorganic surface-treated with silane coupling agent after surface treatment with silazane compound A resin composition comprising a filler, wherein the content of the component (D) is 50 to 80% by mass with respect to 100% by mass of the nonvolatile content in the resin composition.
(2) The resin composition according to the above (1), wherein the content of the component (D) is 55 to 75% by mass.
(3) The resin composition according to the above (1) or (2), wherein the inorganic filler is silica having an average particle size of 1 μm or less and a maximum particle size of 5 μm or less.
(4) The resin composition according to any one of (1) to (3), wherein the weight average molecular weight of the phenoxy resin and / or polyvinyl acetal resin is 8,000 to 150,000.
(5) The epoxy content of the epoxy resin in which the total content of the components (A) and (B) is 15 to 50% by mass with respect to 100% by mass of the nonvolatile content in the resin composition, and is present in the resin composition Any one of the above (1) to (4), wherein the ratio of the total number of groups to the total number of reactive groups of the epoxy curing agent (epoxy group: reactive group) is 1: 0.4 to 2.0. Resin composition.
(6) The resin composition according to any one of (1) to (5), wherein the content of the component (C) is 1 to 10% by mass with respect to 100% by mass of the nonvolatile content in the resin composition.
(7) An adhesive film in which the layer of the resin composition according to any one of (1) to (6) is formed on a support film.
(8) A prepreg in which the resin composition according to any one of (1) to (6) is impregnated in a sheet-like fiber base material composed of fibers.
(9) A circuit board including an insulating layer formed of a cured product of the resin composition according to any one of (1) to (6).

  While the resin composition of the present invention contains a relatively large amount of inorganic filler, it has excellent laminating properties when used in the form of an insulating resin sheet, and can form an insulating layer with high flatness. The obtained insulating layer can form a high peel strength conductor layer even if the surface roughness is low. Therefore, by using the resin composition of the present invention, it is possible to realize an insulating layer (particularly an interlayer insulating layer) that has a low coefficient of thermal expansion and is advantageous for forming fine wiring, and as a result, has a high function having fine wiring. In addition, a highly reliable circuit board can be formed.

Hereinafter, the present invention will be described with reference to preferred embodiments thereof.
The resin composition of the present invention (hereinafter also abbreviated as “the present composition”) includes (A) a polyfunctional epoxy resin, (B) a curing agent, (C) a phenoxy resin and / or a polyvinyl acetal resin. , (D) a resin composition containing at least an inorganic filler surface-treated with a silazane compound and then surface-treated with a silane coupling agent, and the component (D) with respect to 100% by mass of the nonvolatile content in the resin composition The main feature is that 50 to 80% by mass is contained.

[(A) Multifunctional epoxy resin]
A polyfunctional epoxy resin refers to an epoxy resin having two or more epoxy groups in one molecule.

  Examples of the polyfunctional epoxy resin include bisphenol A type epoxy resin, biphenyl type epoxy resin, naphthol type epoxy resin, naphthalene type epoxy resin, bisphenol F type epoxy resin, phosphorus-containing epoxy resin, bisphenol S type epoxy resin, and alicyclic type. Epoxy resin, aliphatic chain epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol A novolac type epoxy resin, epoxy resin having butadiene structure, diglycidyl etherified product of bisphenol, diglycidyl etherified product of naphthalenediol , Glycidyl ethers of phenols, and diglycidyl ethers of alcohols, and alkyl-substituted products, halides and hydrogenated products of these epoxy resins And the like. One of these polyfunctional epoxy resins can be used, or two or more can be mixed and used.

  Among these, polyfunctional epoxy resins are bisphenol A type epoxy resin, naphthol type epoxy resin, naphthalene type epoxy resin, biphenyl type epoxy resin, butadiene from the viewpoint of heat resistance, insulation reliability, adhesion to metal film, etc. An epoxy resin having a structure is preferred. The polyfunctional epoxy resin may be liquid or solid, but from the viewpoint of balance of meltability, film formability, physical properties, etc., the liquid polyfunctional epoxy resin and the solid polyfunctional epoxy resin A mode in which is used in combination is preferred. Here, “liquid” and “solid” refer to the state of the epoxy resin at room temperature (25 ° C.).

  The solid polyfunctional epoxy resin is preferably an aromatic polyfunctional epoxy resin, more preferably a naphthol type epoxy resin, a naphthalene type epoxy resin, from the viewpoint of high glass transition temperature and low coefficient of thermal expansion. Biphenyl type epoxy resin, biphenyl aralkyl type epoxy resin and the like. Two or more solid polyfunctional epoxy resins may be mixed and used.

  Preferred examples of the liquid polyfunctional epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolac type epoxy resin, naphthalene type epoxy resin, cyclohexanedimethanol type epoxy resin, and glycidylamine type epoxy resin. . Two or more liquid polyfunctional epoxy resins may be mixed and used.

  When liquid polyfunctional epoxy resin and solid polyfunctional epoxy resin are used in combination, the usage ratio of liquid polyfunctional epoxy resin and solid polyfunctional epoxy resin (liquid polyfunctional epoxy resin: solid polyfunctional epoxy resin) is non-volatile The mass ratio is preferably 5-60: 95-40, more preferably 10-50: 90-50. If the ratio of the liquid polyfunctional epoxy resin is too small outside this range, when the insulating resin sheet is formed by the composition of the present invention, the flexibility and melt fluidity of the insulating resin sheet tend to decrease, When the ratio of the liquid polyfunctional epoxy resin is too large, the glass transition temperature of the insulating resin sheet tends to decrease and the coefficient of thermal expansion tends to increase.

  Specific examples of the polyfunctional epoxy resin include, as the liquid polyfunctional epoxy resin, for example, liquid bisphenol A type epoxy resin (“jER828EL” (epoxy equivalent: 189) manufactured by Japan Epoxy Resin Co., Ltd.), liquid bisphenol F type Epoxy resin (Japan Epoxy Resin Co., Ltd. “jER806” (epoxy equivalent: 165)), phenol novolac type epoxy resin (Japan Epoxy Resin Co., Ltd. “jER152” (epoxy equivalent: 175)), naphthalene type bifunctional epoxy Resins (“HP4032”, “HP4032D” (epoxy equivalent: 144) manufactured by Dainippon Ink & Chemicals, Inc.), liquid bifunctional epoxy resin (“ZX1658” (epoxy equivalent: 135) manufactured by Tohto Kasei Co., Ltd.), etc. Can be mentioned.

  In addition, as the solid polyfunctional epoxy resin, naphthalene type tetrafunctional epoxy resin (“HP4700” (epoxy equivalent: 162) manufactured by Dainippon Ink & Chemicals, Inc.), naphthol type epoxy resin (manufactured by Toto Kasei Co., Ltd.) ESN-475V "(epoxy equivalent: 332)), epoxy resin having a butadiene structure (" PB-3600 "manufactured by Daicel Chemical Industries, Ltd.), epoxy resin having a biphenyl structure (" NC3000H "manufactured by Nippon Kayaku Co., Ltd.) , “NC3000L” (epoxy equivalent: 269), “YX4000” (epoxy equivalent: 192) manufactured by Japan Epoxy Resin Co., Ltd.), and the like.

  In the present invention, the “polyfunctional epoxy resin” preferably has an epoxy equivalent in the range of 90 to 500 from the viewpoint of reactivity. Here, the epoxy equivalent is the mass (g) of the resin containing an epoxy group, and is measured according to the method defined in JIS K 7236.

[(B) Curing agent]
In the present invention, the curing agent is not particularly limited as long as it has a function of curing the epoxy resin. Preferred examples thereof include a phenol-based curing agent, a naphthol-based curing agent, an active ester-based curing agent, and a benzoxazine. Examples thereof include a system curing agent and a cyanate ester resin. Any one of these curing agents may be used, or two or more may be mixed and used.

  As a phenol type hardening | curing agent and a naphthol type | system | group hardening | curing agent, from a heat resistant and water-resistant viewpoint, the phenol type hardening | curing agent which has a novolak structure, and the naphthol type hardening | curing agent which has a novolak structure are preferable. Examples of commercially available products include MEH-7700, MEH-7810, MEH7851-4H (Maywa Kasei Co., Ltd.), NHN, CBN, GPH (Nippon Kayaku Co., Ltd.), SN170, SN180, SN190, and SN475. SN485, SN495, SN375, SN395 (manufactured by Toto Kasei Co., Ltd.), LA7052, LA7054 (manufactured by Dainippon Ink & Chemicals, Inc.), and the like. Examples of the active ester curing agent include EXB-9460 (Dainippon Ink Chemical Co., Ltd.), DC808, YLH1030 (Japan Epoxy Resin Co., Ltd.) and the like. Examples of the benzoxazine-based curing agent include HFB2006M (manufactured by Showa Polymer Co., Ltd.), Pd, Fa (manufactured by Shikoku Kasei Kogyo Co., Ltd.), and the like. Specific examples of the cyanate ester resin include, for example, bisphenol A dicyanate, polyphenol cyanate (oligo (3-methylene-1,5-phenylene cyanate), 4,4′-methylenebis (2,6-dimethylphenyl cyanate), 4, 4'-ethylidenediphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis (4-cyanate) phenylpropane, 1,1-bis (4-cyanatephenylmethane), bis (4-cyanate-3,5- Bifunctional cyanate resins such as dimethylphenyl) methane, 1,3-bis (4-cyanatephenyl-1- (methylethylidene)) benzene, bis (4-cyanatephenyl) thioether, bis (4-cyanatephenyl) ether, phenol Novolac, cle Examples include polyfunctional cyanate resins derived from arn novolac, etc., prepolymers in which these cyanate resins are partially triazines, etc. Examples of commercially available cyanate ester resins include phenol novolac type polyfunctional cyanate ester resins (Lonza Japan Ltd.). ) “PT30”, cyanate equivalent 124), or a prepolymer in which a part or all of bisphenol A dicyanate is triazine-modified (“BA230” manufactured by Lonza Japan Co., Ltd., cyanate equivalent 232) and the like. .

  In the resin composition of the present invention, when sufficient curing is performed, the total content of the “polyfunctional epoxy resin” and the “epoxy curing agent” is 100% by mass of the nonvolatile content in the resin composition. It is preferable that it is 15-50 mass%. Furthermore, both of these ratios of the total number of epoxy groups in the epoxy resin and the total number of reactive groups in the epoxy curing agent present in the resin composition (total number of epoxy groups: total number of reactive groups in the epoxy curing agent) ) Is preferably 1: 0.4 to 2.0, more preferably 1: 0.5 to 1.5. The total number of epoxy groups in the epoxy resin present in the resin composition is a value obtained by dividing the value obtained by dividing the solid content mass of each epoxy resin by the epoxy equivalent for all epoxy resins. The total number of reactive groups (active hydroxyl group, active ester group, etc.) is a value obtained by totaling the values obtained by dividing the solid content mass of each curing agent by the reactive group equivalent for all curing agents.

  In addition to the curing agent, a curing accelerator can be further added to the composition of the present invention. Examples of the curing accelerator include organic phosphine compounds, organic phosphonium salt compounds, imidazole compounds, amine adduct compounds, and tertiary amine compounds. Specific examples of organic phosphine compounds and organic phosphonium salt compounds include TPP, TPP-K, TPP-S, TPTP-S, TBP-DA, TPP-SCN, TPTP-SCN (trade name of Hokuko Chemical Co., Ltd.), etc. Is mentioned. Specific examples of the imidazole compound include Curazole 2MZ, 2E4MZ, C11Z, C11Z-CN, C11Z-CNS, C11Z-A, 2MZ-OK, 2MA-OK, 2PHZ (trade names of Shikoku Kasei Kogyo Co., Ltd.). . Specific examples of the amine adduct compound include Novacure (trade name of Asahi Kasei Kogyo Co., Ltd.) and Fuji Cure (trade name of Fuji Kasei Kogyo Co., Ltd.). Specific examples of the tertiary amine compound include DBU (1,8-diazabiccyclo [5,4,0] undec-7-ene). Two or more curing accelerators may be mixed and used. In the resin composition of the present invention, the content of the curing accelerator is usually in the range of 0.1 to 5 mass% with respect to the total amount (nonvolatile content) of the epoxy resin and the epoxy curing agent contained in the resin composition. used.

  When using a cyanate ester resin as an epoxy curing agent, for the purpose of shortening the curing time, an organometallic compound that has been conventionally used as a curing catalyst in a system in which an epoxy resin and a cyanate compound are used together is added. Also good. Examples of organometallic compounds include organic copper compounds such as copper (II) acetylacetonate, organic zinc compounds such as zinc (II) acetylacetonate, and organic such as cobalt (II) acetylacetonate and cobalt (III) acetylacetonate. A cobalt compound etc. are mentioned. The addition amount of the organometallic compound is usually in the range of 10 to 500 ppm, preferably 25 to 200 ppm in terms of metal with respect to the cyanate ester resin. Two or more organometallic compounds may be mixed and used. In a system using such a cyanate ester resin and an organometallic compound, the organometallic compound and one or more optional curing accelerators may be used in combination.

[(C) Phenoxy resin, polyvinyl acetal resin]
The resin composition of the present invention contains a phenoxy resin and / or a polyvinyl acetal resin. The weight average molecular weight of the phenoxy resin and / or polyvinyl acetal resin is preferably in the range of 8,000 to 150,000, more preferably in the range of 10,000 to 60,000, and in the range of 20,000 to 60,000. It is particularly preferred. When the weight average molecular weight of the phenoxy resin and / or the polyvinyl acetal resin is smaller than the preferred range, the peel strength of the conductor layer on the insulating layer formed by the resin composition of the present invention tends to decrease, and from this range. If it is large, the thermal expansion coefficient of the insulating layer and the roughness of the surface of the insulating layer after the roughening treatment tend to increase.

  The “weight average molecular weight” here is measured by gel permeation chromatography (GPC) method (polystyrene conversion). Specifically, the weight average molecular weight by the GPC method is LC-9A / RID-6A manufactured by Shimadzu Corporation as a measuring device, and Shodex K-800P / K-804L / K- manufactured by Showa Denko KK as a column. 804 L can be measured at a column temperature of 40 ° C. using chloroform or the like as a mobile phase, and can be calculated using a standard polystyrene calibration curve.

  The phenoxy resin and the polyvinyl acetal resin may be used either alone or in combination, but the compatibility in the epoxy resin composition and the conductor layer formed on the insulating layer From the viewpoint of the peel strength, it is preferable to use at least a phenoxy resin. Each of the phenoxy resin and the polyvinyl acetal resin can be used alone or in combination of two or more.

  Examples of the phenoxy resin include bisphenol A skeleton, bisphenol F skeleton, bisphenol S skeleton, bisphenol acetophenone skeleton, novolac skeleton, biphenyl skeleton, fluorene skeleton, dicyclopentadiene skeleton, norbornene skeleton, naphthalene skeleton, anthracene skeleton, adamantane skeleton, terpene skeleton, Examples thereof include those having one or more skeletons selected from a trimethylcyclohexane skeleton. The terminal of the phenoxy resin may be any functional group such as a phenolic hydroxyl group or an epoxy group. Examples of commercially available phenoxy resins include 1256, 4250 (bisphenol A skeleton-containing phenoxy resin) manufactured by Japan Epoxy Resin Co., Ltd., YX8100 (bisphenol S skeleton-containing phenoxy resin) manufactured by Japan Epoxy Resin Co., Ltd., Japan Epoxy Resin ( YX6954 (bisphenol acetophenone skeleton-containing phenoxy resin) manufactured by Co., Ltd., FX280, FX293 manufactured by Toto Kasei Co., Ltd., YL7553BH30, YL6794, YL7213, YL7290, YL7482 manufactured by Japan Epoxy Resins Co., Ltd. and the like can be mentioned.

  The polyvinyl acetal resin is preferably a polyvinyl butyral resin, and specific examples of the polyvinyl acetal resin include those manufactured by Denki Kagaku Kogyo Co., Ltd., Electric Butyral 4000-2, 5000-A, 6000-C, 6000-EP, Sekisui Chemical Co., Ltd. ) Made S-Rec BH series, BX series, KS series, BL series, BM series and the like.

  The content of the phenoxy resin and / or the polyvinyl acetal resin in the resin composition of the present invention is preferably in the range of 1 to 20% by mass with respect to 100% by mass of the nonvolatile content in the resin composition, and 2 to 15% by mass. % Is more preferable. If the content is too small, the desired effects of increasing the filling of the inorganic filler and increasing the peel strength of the conductor layer on the insulating layer tend not to be obtained sufficiently, and if the content is too large, the resin composition When the layer of the resin composition is formed on the conductor pattern, embedding (embedding of the composition between adjacent patterns (wiring)) or the like becomes difficult, or the resin composition As a result, the laminating property of the insulating resin sheet formed tends to decrease.

[(D) Inorganic filler surface-treated with silazane compound and then surface-treated with silane coupling agent]
In the resin composition of the present invention, the inorganic filler surface-treated with the silazane compound and then surface-treated with the silane coupling agent is blended for the purpose of reducing the thermal expansion coefficient of the insulating layer formed from the resin composition. However, since the inorganic filler exhibits excellent dispersibility in the resin composition, the resin composition can be made to exhibit a relatively low melt viscosity even when blended in a relatively large amount, and the inorganic filler This contributes to the formation of an insulating layer whose material is highly filled. On the other hand, the insulating layer obtained by heat-curing the resin composition containing the inorganic filler has improved adhesion to the conductor layer (plating layer) due to the presence of the inorganic filler and the phenoxy resin and / or polyvinyl acetal resin. This makes it possible to form an insulating layer having excellent adhesion to the conductor layer, although the surface roughness obtained by the roughening treatment is small.

  Examples of the inorganic filler to be surface-treated include silica, alumina, barium sulfate, talc, clay, mica powder, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, and boric acid. Aluminum, barium titanate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, barium zirconate, calcium zirconate, etc., among these, silica (spherical silica, amorphous silica, Fused silica, crystalline silica, synthetic silica, etc.) are preferred, and spherical silica is particularly preferred. Such inorganic fillers may be used alone or in combination of two or more.

  The average particle diameter of the inorganic filler subjected to the surface treatment is preferably 1 μm or less, more preferably 0.8 μm or less, and particularly preferably 0.7 μm or less. When the average particle diameter of the inorganic filler exceeds 1 μm, the peel strength of the conductor layer when the conductor layer is formed by plating on the insulating layer formed from the resin composition tends to decrease. If the average particle size of the inorganic filler is too small, the viscosity of the varnish tends to increase and the handleability tends to decrease when the resin composition is a resin varnish. It is preferable that it is 05 μm or more. Even if the average particle diameter of the inorganic filler is 1 μm or less, if it contains a large amount of coarse particles, irregularities derived from coarse particles are produced during the roughening treatment, and plated copper penetrates into the irregularities when forming a conductor layer by plating. However, it becomes easy to short-circuit between the miniaturized conductors. Therefore, the inorganic filler preferably has a maximum particle size of 5 μm or less.

  The average particle diameter and the maximum particle diameter of the inorganic filler to be subjected to the surface treatment here can be measured by a laser diffraction / scattering method based on Mie scattering theory. Specifically, the particle size distribution of the inorganic filler is created on a volume basis with a laser diffraction particle size distribution measuring device, the median diameter (50% value) is the average particle diameter, and the 5% value is the maximum particle diameter. Measured in As the measurement sample, an inorganic filler dispersed in water by ultrasonic waves can be preferably used. As a laser diffraction type particle size distribution measuring apparatus, LA-500 manufactured by Horiba, Ltd. or the like can be used.

  Examples of the silazane compound used for the surface treatment include hexamethyldisilazane, 1,3-divinyl-1,1,3,3-tetramethyldisilazane, octamethyltrisilazane, hexa (t-butyl) disilazane, Hexabutyldisilazane, hexaoctyldisilazane, 1,3-diethyltetramethyldisilazane, 1,3-di-n-octyltetramethyldisilazane, 1,3-diphenyltetramethyldisilazane, 1,3-dimethyltetra Phenyldisilazane, 1,3-diethyltetramethyldisilazane, 1,1,3,3-tetraphenyl-1,3-dimethyldisilazane, 1,3-dipropyltetramethyldisilazane, hexamethylcyclotrisilazane, Hexaphenyldisilazane, dimethylaminotrimethylsilazane, trisilazane, cyclo Examples include trisilazane, 1,1,3,3,5,5-hexamethylcyclotrisilazane, and hexamethyldisilazane is particularly preferable.

  Examples of the silane coupling agent used for the surface treatment include 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropyltriethoxysilane, 3-glycidyloxypropyl (dimethoxy) methylsilane, and 2- (3, Epoxy silane coupling agents such as 4-epoxycyclohexyl) ethyltrimethoxysilane; 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropylmethyldimethoxysilane and 11-mercaptoundecyltrimethoxysilane Mercapto silane coupling agents such as: 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyldimethoxymethylsilane, N-phenyl 3-aminopropyltrimethoxysilane, N-methylaminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane and N- (2-aminoethyl) -3-aminopropyldimethoxymethylsilane Amino silane coupling agents such as; ureido silane coupling agents such as 3-ureidopropyltriethoxysilane; vinyl silane coupling agents such as vinyltrimethoxysilane, vinyltriethoxysilane and vinylmethyldiethoxysilane; p A styryl silane coupling agent such as styryltrimethoxysilane; an acrylate silane coupling agent such as 3-acryloxypropyltrimethoxysilane and 3-methacryloxypropyltrimethoxysilane; Isocyanate-based silane coupling agents such as propyl propyltrimethoxysilane, sulfide-based silane coupling agents such as bis (triethoxysilylpropyl) disulfide and bis (triethoxysilylpropyl) tetrasulfide; methyltrimethoxysilane, octadecyltrimethoxysilane , Phenyltrimethoxysilane, methacryloxypropyltrimethoxysilane, imidazolesilane, triazinesilane and the like. Of these, aminosilane coupling agents, epoxysilane coupling agents, and imidazolesilane are preferable.

  For example, the surface treatment of the inorganic filler may be performed by adding and spraying a silazane compound and stirring for 5 to 15 minutes while stirring and dispersing the untreated inorganic filler at room temperature with a mixer, followed by adding a silane coupling agent. This can be done by spraying with addition and stirring for 5-15 minutes. In addition, an inorganic filler surface-treated with a commercially available silazane compound (inorganic filler with silazane compound treatment) can be used. In this case, the inorganic filler surface-treated with a commercially available silazane compound is used at room temperature. What is necessary is just to carry out by adding and spraying a silane coupling agent and stirring for 5 to 15 minutes while stirring and dispersing. In order to firmly adhere the silazane compound and / or silane coupling agent to the inorganic filler, the inorganic filler may be taken out from the mixer after the above operation and allowed to stand for more than one day. A slight heat treatment may be performed after the stirring operation after adding and spraying the compound and / or after the stirring operation after adding and spraying the silane coupling agent. In order to uniformly deposit the silazane compound and / or silane coupling agent on the inorganic filler, an organic solvent is added and mixed after the addition spray of the silazane compound and / or after the addition spray of the silane coupling agent. May be. As the mixer, known mixers can be used, for example, blenders such as V blenders, ribbon blenders and bubble cone blenders, mixers such as Henschel mixers and concrete mixers, ball mills, etc., and mixers are preferably used. Is done.

  The treatment amount of the silazane compound is preferably about 0.01 to 1.0 part by mass per 100 parts by mass of the inorganic filler. Moreover, the processing amount of the silane coupling agent is preferably about 0.5 to 2 parts by mass per 100 parts by mass of the inorganic filler. In addition, when using the inorganic filler with silazane compound processing of a commercial item, the processing amount of a silane coupling agent has about 0.5-2 mass parts per 100 mass parts of inorganic fillers with silazane compound treatment.

  Use an inorganic filler that has been surface-treated with either a silazane or a silane coupling agent, or an inorganic filler that has been surface-treated with a silane coupling agent first, followed by a surface treatment with a silazane. However, even if an inorganic filler that has been surface-treated by mixing silazane and a silane coupling agent is used, the desired effect, ie, low melt viscosity of the resin composition and conductor of the insulating layer can be obtained. The effect of sufficiently exhibiting both improvement in adhesion to the layer cannot be obtained.

  It is preferable that content of the said inorganic filler (component (D)) in the resin composition of this invention is the range of 50-80 mass% with respect to 100 mass% of non volatile matters in a resin composition. It is more preferably in the range of 75% by mass, particularly preferably in the range of 60 to 70% by mass. When the content of the inorganic filler is too small, the thermal expansion coefficient of the insulating resin sheet or the insulating layer formed by the resin composition tends to increase. When the content is too large, the flexibility of the insulating resin sheet is increased. Tend to decrease.

[Rubber particles]
The resin composition of the present invention may contain rubber particles for the purpose of improving the mechanical strength of the cured product and relaxing the stress. The rubber particles are not dissolved in an organic solvent when preparing the resin composition, are not compatible with components in the resin composition such as an epoxy resin, and exist in a dispersed state in the varnish of the resin composition Is preferred. Such rubber particles can generally be prepared by increasing the molecular weight of the rubber component to a level that does not dissolve in an organic solvent or resin and making it into particles. Specifically, core-shell type rubber particles, Examples thereof include acrylonitrile butadiene rubber particles, crosslinked styrene butadiene rubber particles, and acrylic rubber particles. The core-shell type rubber particles are rubber particles having a core layer and a shell layer. For example, the outer shell layer is a glassy polymer and the inner core layer is a rubbery polymer. Examples include a three-layer structure in which the shell layer is a glassy polymer, the intermediate layer is a rubbery polymer, and the core layer is a glassy polymer. The glass layer is made of, for example, a polymer of methyl methacrylate, and the rubbery polymer layer is made of, for example, a butyl acrylate polymer (butyl rubber). Specific examples of the core-shell type rubber particles include Staphyloid AC3832, AC3816N, (Ganz Kasei Co., Ltd. trade name), and Metabrene KW-4426 (Mitsubishi Rayon Co., Ltd. trade name). Specific examples of acrylonitrile butadiene rubber (NBR) particles include XER-91 (average particle size 0.5 μm, manufactured by JSR Corporation). Specific examples of styrene butadiene rubber (SBR) particles include XSK-500 (average particle size 0.5 μm, manufactured by JSR Corporation). Specific examples of the acrylic rubber particles include methabrene W300A (average particle size 0.1 μm), W450A (average particle size 0.5 μm) (manufactured by Mitsubishi Rayon Co., Ltd.).

  The average particle diameter of the rubber particles is preferably in the range of 0.005 to 1 μm, and more preferably in the range of 0.2 to 0.6 μm. The average particle diameter of such rubber particles can be measured using a dynamic light scattering method. For example, rubber particles are uniformly dispersed in a suitable organic solvent by ultrasonic waves, etc., and using FPRA-1000 (manufactured by Otsuka Electronics Co., Ltd.), the particle size distribution of the rubber particles is created on a mass basis, and the median diameter is determined. The average particle diameter is measured.

  When the rubber particles are blended, the content is preferably in the range of 1 to 10% by mass and more preferably in the range of 2 to 5% by mass with respect to 100% by mass of the nonvolatile content in the resin composition. .

[Thermosetting resin]
The resin composition of the present invention contains a thermosetting resin other than an epoxy resin, such as a maleimide compound, a bisallyl nadiimide compound, a vinyl benzyl resin, and a vinyl benzyl ether resin, as long as the effects of the present invention are exhibited as necessary. It can also be blended. Such thermosetting resins may be used in combination of two or more. As maleimide resins, BMI1000, BMI2000, BMI3000, BMI4000, BMI5100 (manufactured by Daiwa Kasei Kogyo Co., Ltd.), BMI, BMI-70, BMI-80 (manufactured by KEI Kasei Co., Ltd.), ANILIX-MI (Mitsui Chemical Fine) BANI-M, BANI-X (manufactured by Maruzen Petrochemical Co., Ltd.) as a vinyl benzyl resin, V5000 (manufactured by Showa Polymer Co., Ltd.), vinyl benzyl ether resin V1000X, V1100X (manufactured by Showa Polymer Co., Ltd.).

[Flame retardants]
The resin composition of the present invention may contain a flame retardant as long as the effects of the present invention are exhibited. Two or more flame retardants may be mixed and used. Examples of the flame retardant include an organic phosphorus flame retardant, an organic nitrogen-containing phosphorus compound, a nitrogen compound, a silicone flame retardant, and a metal hydroxide. Examples of organic phosphorus flame retardants include phenanthrene-type phosphorus compounds such as HCA, HCA-HQ, and HCA-NQ manufactured by Sanko Co., Ltd., phosphorus-containing benzoxazine compounds such as HFB-2006M manufactured by Showa Polymer Co., Ltd., and Ajinomoto Reefos 30, 50, 65, 90, 110, Fine Techno Co., TPP, RPD, BAPP, CPD, TCP, TXP, TBP, TOP, KP140, TIBP, PPQ, Clariant (made by Hokuko Chemical Co., Ltd.) Phosphoric acid ester compounds such as OP930 manufactured by Daihachi Chemical Co., Ltd., FX289 compounds manufactured by Tohto Kasei Co., Ltd., phosphorus-containing epoxy resins such as FX305, phosphorus such as ERF001 manufactured by Tohto Kasei Co., Ltd. Examples thereof include phenoxy resin. Examples of organic nitrogen-containing phosphorus compounds include phosphate ester compounds such as SP670 and SP703 manufactured by Shikoku Kasei Kogyo Co., Ltd., phosphazenes such as SPB100 and SPE100 manufactured by Otsuka Chemical Co., Ltd., and FP-series manufactured by Fushimi Seisakusho Co., Ltd. Compounds and the like. As the metal hydroxide, magnesium hydroxide such as UD65, UD650, UD653 manufactured by Ube Materials Co., Ltd., B-30, B-325, B-315, B-308, B manufactured by Sakai Kogyo Co., Ltd. And aluminum hydroxide such as -303 and UFH-20.

  The resin composition of the present invention may optionally contain various resin additives other than the components described above as long as the effects of the present invention are exhibited. Examples of such resin additives include organic fillers such as silicon powder, nylon powder, and fluorine powder, thickeners such as olben and benton, silicone-based, fluorine-based, and polymer-based antifoaming agents or leveling agents. Adhesion imparting agents such as silane coupling agents, triazole compounds, thiazole compounds, triazine compounds, porphyrin compounds, coloring agents such as phthalocyanine blue, phthalocyanine green, iodin green, disazo yellow, carbon black, etc. it can.

[Insulating resin sheet]
An adhesive film is obtained by forming a layer of the resin composition of the present invention on a support, and the resin composition of the present invention is impregnated in a sheet-like substrate (sheet-like fiber substrate) made of fibers. Thus, a prepreg can be obtained. The resin composition of the present invention can be directly applied to a circuit board to form an insulating layer, but industrially, the resin composition of the present invention is used to form an insulating resin sheet such as the above adhesive film or prepreg. It is preferable to form and form an insulating layer on the circuit board using the insulating resin sheet.

  The adhesive film using the resin composition of the present invention is prepared by a method known to those skilled in the art, for example, by preparing a resin varnish in which the resin composition is dissolved in an organic solvent, and applying the resin varnish on a support. It can be produced by drying the organic solvent by heating or blowing hot air to form the resin composition layer.

  Examples of the organic solvent include ketones such as acetone, methyl ethyl ketone and cyclohexanone, acetates such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate and carbitol acetate, and carbitols such as cellosolve and butyl carbitol. , Aromatic hydrocarbons such as toluene and xylene, amide solvents such as dimethylformamide, dimethylacetamide, and N-methylpyrrolidone. One organic solvent may be used, or two or more organic solvents may be used in combination.

  The drying conditions are not particularly limited, but the drying is performed so that the content ratio of the organic solvent in the resin composition layer is usually 10% by mass or less, preferably 5% by mass or less. As drying conditions, suitable drying conditions can be appropriately set by simple experiments. Depending on the amount of organic solvent in the varnish, for example, a varnish containing 30 to 60% by mass of an organic solvent can be dried at 50 to 150 ° C. for about 3 to 10 minutes.

  In general, the thickness of the resin composition layer formed in the adhesive film is equal to or greater than the thickness of the conductor layer of the circuit board. Since the thickness of the conductor layer of the circuit board is usually in the range of 5 to 70 μm, the thickness of the resin composition layer is preferably 10 to 100 μm. The resin composition layer may be protected by a protective film described later. By protecting with a protective film, it is possible to prevent dust and the like from being attached to the surface of the resin composition layer and scratches.

  Examples of the support used for the adhesive film include polyolefins such as polyethylene, polypropylene and polyvinyl chloride, polyethylene terephthalate (hereinafter sometimes abbreviated as “PET”), polyesters such as polyethylene naphthalate, plastics such as polycarbonate and polyimide. A film is mentioned. As the plastic film, PET is particularly preferable. Moreover, it can also be set as an adhesive film with metal foil by using metal foil, such as copper foil and aluminum foil, as a support body. The protective film is preferably a plastic film similar to the support. Further, the support and the protective film may be subjected to a release treatment in addition to the mat treatment and the corona treatment. Examples of the release treatment include a release treatment with a release agent such as a silicone resin release agent, an alkyd resin release agent, and a fluororesin release agent.

  Although the thickness of a support body is not specifically limited, Usually, it is 10-150 micrometers, Preferably it is used in 25-50 micrometers. The thickness of the protective film is not particularly limited, but is usually 1 to 40 μm, preferably 10 to 30 μm.

  The support in the adhesive film is peeled after the adhesive film is laminated on a circuit board or the like, or after the resin composition layer is heated and cured to form an insulating layer after lamination. If the support is peeled off after the resin composition layer is heat-cured, adhesion of dust and the like in the curing step can be prevented, and the surface smoothness of the insulating layer after curing can be improved. In the case of peeling after curing, the support is usually subjected to a release treatment in advance. In addition, it is preferable to form the resin composition layer formed on a support body so that the area of a layer may become smaller than the area of a support body. The adhesive film can be wound up in a roll shape and stored and stored.

  A circuit board such as a multilayer printed wiring board using the adhesive film of the present invention can be produced, for example, as follows. When the resin composition layer of the adhesive film is protected by a protective film, after peeling these, the adhesive film is laminated on one or both sides of the inner circuit board so that the resin composition layer is in direct contact with the inner circuit board . In the adhesive film of the present invention, a method of laminating the inner layer circuit board under reduced pressure by a vacuum laminating method is preferably used. The laminating method may be a batch method or a continuous method using a roll. Further, the adhesive film and the inner layer circuit board may be heated (preheated) as necessary before lamination.

  The “inner circuit board” as used in the present invention is mainly a conductor layer patterned on one or both sides of a substrate such as a glass epoxy, metal substrate, polyester substrate, polyimide substrate, BT resin substrate, thermosetting polyphenylene ether substrate, etc. (Circuit) is formed. In addition, when manufacturing a multilayer printed wiring board in which conductor layers and insulating layers are alternately formed, and one or both surfaces are patterned conductor layers (circuits), an insulating layer and a conductor layer are further formed. The intermediate product to be included is also included in the inner layer circuit board in the present invention. In the inner layer circuit board, the surface of the conductor circuit layer is preferably roughened by a blackening process or the like from the viewpoint of adhesion of the insulating layer to the inner layer circuit board.

The laminating conditions are preferably a pressure bonding temperature (laminating temperature) of 70 to 140 ° C. and a pressure bonding pressure of preferably 1 to 11 kgf / cm ² (9.8 × 10 ^{4 to} 107.9 × 10 ⁴ N / m ² ). Lamination is preferably performed under a reduced pressure of 20 mmHg (26.7 hPa) or less.

  The vacuum lamination can be performed using a commercially available vacuum laminator. Examples of commercially available vacuum laminators include a vacuum applicator manufactured by Nichigo-Morton, a vacuum pressurizing laminator manufactured by Meiki Seisakusho, a roll dry coater manufactured by Hitachi Industries, Ltd., and Hitachi Air Examples include a vacuum laminator manufactured by EC Co., Ltd.

  After laminating the adhesive film on the inner layer circuit board, when the support is peeled off, the insulating film can be formed on the inner layer circuit board by peeling and thermosetting. The conditions of heat curing are selected in the range of 20 to 180 minutes at 150 to 220 ° C, more preferably 30 to 120 minutes at 160 to 200 ° C. In addition, when a support body is not peeled before hardening, it peels after formation of an insulating layer.

  Next, holes are formed in the insulating layer formed on the inner circuit board to form via holes and through holes. Drilling can be performed by a known method such as drilling, laser, or plasma, or a combination of these methods if necessary. However, drilling by a laser such as a carbon dioxide laser or YAG laser is the most common method. .

  Next, a roughening process is performed on the surface of the insulating layer. The roughening treatment in the present invention is usually preferably carried out by a wet roughening method using an oxidizing agent. Examples of the oxidizing agent include permanganate (potassium permanganate, sodium permanganate, etc.), dichromate, ozone, hydrogen peroxide / sulfuric acid, nitric acid and the like. Preferably, an alkaline permanganate solution (for example, potassium permanganate, sodium hydroxide aqueous solution of sodium permanganate), which is an oxidizer widely used for roughening an insulating layer in the production of a multilayer printed wiring board by a built-up method. It is preferable to perform roughening using.

  The roughness of the roughened surface obtained by roughening the surface of the insulating layer is preferably 50 to 500 nm in terms of Ra when forming fine wiring. Here, the Ra value is a kind of numerical value representing the surface roughness, and is called arithmetic average roughness. Specifically, the absolute value of the height changing in the measurement region is expressed by the average line. Measured from a certain surface and arithmetically averaged. For example, using WYKO NT3300 manufactured by Becoin Instruments Co., Ltd., it can be obtained from a numerical value obtained with a measurement range of 121 μm × 92 μm using a VSI contact mode and a 50 × lens.

  Next, a conductor layer is formed on the roughened insulating layer surface by a method combining electroless plating and electrolytic plating. Alternatively, a plating resist having a pattern opposite to that of the conductor layer can be formed, and the conductor layer can be formed only by electroless plating. In addition, after forming the conductor layer, the peel strength of the conductor layer can be further improved and stabilized by annealing at 150 to 200 ° C. for 20 to 90 minutes. The peel strength of the conductor layer is preferably 0.6 kgf / cm or more.

  Moreover, as a method of patterning the conductor layer to form a circuit, for example, a subtractive method or a semi-additive method known to those skilled in the art can be used.

  A prepreg using the resin composition of the present invention can be produced by impregnating the resin composition of the present invention into a sheet-like fiber base material by a hot melt method or a solvent method and semi-curing by heating.

  As a sheet-like fiber base material, what is commonly used as a fiber base material for a prepreg made of, for example, glass cloth or aramid fiber can be used.

  In the hot melt method, without dissolving the resin in an organic solvent, the resin is once coated on the resin and a coated paper having good releasability, and then laminated on a sheet-like fiber substrate, or directly applied by a die coater. Thus, a prepreg is produced. Similarly to the adhesive film, the solvent method is a method in which a sheet-like fiber base material is immersed in a resin varnish obtained by dissolving a resin in an organic solvent, the resin varnish is impregnated into the sheet-like fiber base material, and then dried.

Production of a circuit board such as a multilayer printed wiring board using the prepreg of the present invention can be performed as follows, for example. One or several prepregs of the present invention are stacked on the inner layer circuit board, and a metal plate is sandwiched through a release film, and press laminated under pressure and heating conditions. The pressure is preferably 5 to 40 kgf / cm ² (49 × 10 ^{4 to} 392 × 10 ⁴ N / m ² ), and the temperature is preferably 120 to 200 ° C. for 20 to 100 minutes. Moreover, it can also be manufactured by laminating to an inner layer circuit board by a vacuum laminating method as in the case of the adhesive film, followed by heat curing. Thereafter, in the same manner as described above, the surface of the prepreg cured with an oxidizing agent is roughened, and then the conductor layer is formed by plating, whereby a circuit board such as a multilayer printed wiring board can be manufactured.

  The insulating resin sheet (adhesive film, prepreg, etc.) in the present invention preferably has an average linear thermal expansion coefficient of 25 to 150 ° C. of the cured product (that is, the cured product of the resin composition of the present invention) of 20 to 40 ppm. More preferably, it is 20-35 ppm. By having such an average linear thermal expansion coefficient, it effectively acts to reduce the thermal expansion coefficient of the circuit board.

  EXAMPLES Hereinafter, although this invention is demonstrated in detail using an Example and a comparative example, these do not restrict | limit this invention in any meaning. In the following description, “part” means “part by mass”.

  14 parts of liquid bisphenol A type epoxy resin (epoxy equivalent 180, “jER828EL” manufactured by Japan Epoxy Resins Co., Ltd.) and 14 parts biphenyl aralkyl type epoxy resin (epoxy equivalent 269, “NC3000L” manufactured by Nippon Kayaku Co., Ltd.) 10 parts of a naphthalene type tetrafunctional epoxy resin (epoxy equivalent 162, “HP-4700” manufactured by DIC Corporation), phenoxy resin (“YX6954BH30” manufactured by Japan Epoxy Resin Co., Ltd. (weight average molecular weight 38000)) is methyl ethyl ketone (hereinafter “ MEK ”) and 20 parts of a resin solution having a nonvolatile content of 30% by mass dissolved in a mixed solvent having a mass ratio of cyclohexanone of 1: 1 were dissolved in 15 parts of MEK and 15 parts of cyclohexanone with stirring. Thereto, 40 parts of a biphenyl aralkyl type phenol resin (MEK solution of Mehkasei Co., Ltd. “MEH7851-4H” having a solid content of 50%, phenolic hydroxyl group equivalent 242), phenol novolac-based curing agent (manufactured by DIC Corporation “ LA-7054 "60% solid MEK solution, phenolic hydroxyl group equivalent 124) 8 parts, curing catalyst (Shikoku Kasei Kogyo Co., Ltd.," 2E4MZ ") 0.1 part, spherical silica (manufactured by Admatechs) 105 parts of “SOC2” (with hexamethyldisilazane treatment, average particle size 0.5 μm) further treated with 1 part of imidazolesilane IM-1000 manufactured by Nikko Metal Co., Ltd., polyvinyl butyral resin solution (Sekisui Chemical) “KS-1” (glass transition temperature 105 ° C., weight average molecular weight: 27000) manufactured by Kogyo Co., Ltd. was mixed with ethanol and toluene Mass ratio of 1: 1 mixed 15% solids resin solution in a solvent) 12 parts were mixed, and uniformly dispersed in a high-speed rotary mixer to prepare a resin varnish. Next, it was coated on a polyethylene terephthalate (thickness 38 μm, hereinafter abbreviated as “PET”) with a die coater so that the thickness of the resin composition after drying was 40 μm, and the temperature was 80 to 120 ° C. (average 100 ) For 7 minutes (residual solvent amount of about 2% by mass). Subsequently, it wound up in roll shape, bonding a 15-micrometer-thick polypropylene film on the surface of a resin composition layer. The roll-like adhesive film was slit to a width of 507 mm, and a sheet-like adhesive film having a size of 507 mm × 336 mm was obtained therefrom.

  14 parts of liquid bisphenol A type epoxy resin (epoxy equivalent 180, “jER828EL” manufactured by Japan Epoxy Resins Co., Ltd.) and 14 parts biphenyl aralkyl type epoxy resin (epoxy equivalent 269, “NC3000L” manufactured by Nippon Kayaku Co., Ltd.) 10 parts of naphthalene-type tetrafunctional epoxy resin (epoxy equivalent 162, “HP-4700” manufactured by DIC Corporation), phenoxy resin (“YX6954BH30” manufactured by Japan Epoxy Resin Co., Ltd. (weight average molecular weight 38000)) of MEK and cyclohexanone 20 parts of a resin solution having a nonvolatile content of 30% by mass dissolved in a mixed solvent having a mass ratio of 1: 1) was dissolved in 15 parts of MEK and 15 parts of cyclohexanone with stirring. There, 40 parts of biphenyl aralkyl type phenol resin (MEK solution of MEH7851-4H manufactured by Meiwa Kasei Co., Ltd., 50% solid content, phenolic hydroxyl group equivalent 242), dicyandiamide (“DICY7” manufactured by Japan Epoxy Resin Co., Ltd.) ) 1 part, curing catalyst (Shikoku Kasei Kogyo Co., Ltd., “2E4MZ”) 0.1 part, spherical silica (“SOC2” manufactured by Admatechs Co., Ltd., with hexamethyldisilazane treatment, average particle size 0.5 μm) A resin varnish was prepared by mixing 160 parts of 100 parts of a imidazolesilane IM-1000 manufactured by Nikko Metal Co., Ltd. and uniformly dispersing the mixture with a high-speed rotary mixer. Next, using this resin varnish, an adhesive film was obtained in the same manner as in Example 1.

  40 parts of a prepolymer of bisphenol A dicyanate ("BA-230-S75" manufactured by Lonza Japan Co., Ltd., MEK solution having a cyanate equivalent of about 232 and a non-volatile content of 75% by mass), a phenol novolac type polyfunctional cyanate ester resin (Lonza Japan ( "PT30" manufactured by Co., Ltd. and cyanate equivalent of about 124) were mixed with 10 parts and 10 parts of MEK, and "ESN-475V" manufactured by Tohto Kasei Co., Ltd. (represented by the following general formula (1)) as a naphthol type epoxy resin. 30 parts of an epoxy resin having an epoxy equivalent of about 340 (a MEK solution having a nonvolatile content of 65% by mass), 10 parts of a liquid bisphenol A type epoxy resin ("jER828EL" manufactured by Japan Epoxy Resin Co., Ltd., epoxy equivalent of about 185), a phenoxy resin solution (Japan Epoxy Resin Co., Ltd. “YL7553 10 parts of a mixed solution of MEK and cyclohexanone having a nonvolatile content of 30% by mass of “H30” (weight average molecular weight 35000), 1% by mass of N, N—cobalt (II) acetylacetonate (manufactured by Tokyo Chemical Industry Co., Ltd.) To 3.5 parts of dimethylformamide (DMF) solution and spherical silica ("SOC2" manufactured by Admatechs Co., Ltd., with hexamethyldisilazane treatment, average particle diameter of 0.5 µm) and epoxy manufactured by Shin-Etsu Chemical Co., Ltd. 110 parts of silane KBM-403 treated) were mixed and dispersed uniformly with a high-speed rotary mixer to prepare a varnish of a thermosetting resin composition. Next, using this resin varnish, an adhesive film was obtained in the same manner as in Example 1.

(N shows the number of 1-6 as an average value, X shows a glycidyl group or a C1-C8 hydrocarbon group, and the ratio of a hydrocarbon group / glycidyl group is 0.05-2.0. )

<Comparative Example 1>
In Example 1, 100 parts of spherical silica (“SOC2” manufactured by Admatechs Co., Ltd. (with hexamethyldisilazane treatment, average particle diameter of 0.5 μm) was further treated with 1 part of imidazolesilane IM-1000 manufactured by Nikko Metal Co., Ltd. Example 1) Except for using 105 parts of spherical silica ("SOC2" (average particle size 0.5 µm) manufactured by Admatechs Co., Ltd.) 105 parts, completely the same as Example 1 except that a varnish of a thermosetting resin composition was used. An adhesive film was obtained in the same manner.

<Comparative example 2>
In Example 1, 100 parts of spherical silica (“SOC2” manufactured by Admatechs Co., Ltd. (with hexamethyldisilazane treatment, average particle diameter of 0.5 μm) was further treated with 1 part of imidazolesilane IM-1000 manufactured by Nikko Metal Co., Ltd. The varnish of the thermosetting resin composition was used, in which 105 parts were changed to 105 parts spherical silica ("SOC2" manufactured by Admatechs (with hexamethyldisilazane treatment, average particle size 0.5 µm)). Except for this, an adhesive film was obtained in the same manner as in Example 1.

<Comparative Example 3>
In Example 1, 100 parts of spherical silica (“SOC2” manufactured by Admatechs Co., Ltd. (with hexamethyldisilazane treatment, average particle diameter of 0.5 μm) was further treated with 1 part of imidazolesilane IM-1000 manufactured by Nikko Metal Co., Ltd. 105 parts of spherical silica ("SOC2" manufactured by Admatechs Co., Ltd. (with imidazole silane treatment, average particle size 0.5 µm)) and 1,1,1,3, manufactured by Tokyo Chemical Industry Co., Ltd. An adhesive film was obtained in exactly the same manner as in Example 1 except that the varnish of the thermosetting resin composition changed to 105 parts) was used, which was obtained by treating 1 part of 3,3-hexamethyldisilazane.

<Comparative example 4>
In Example 3, 100 parts of spherical silica ("SOC2" manufactured by Admatechs Co., Ltd. (with hexamethyldisilazane treatment, average particle size 0.5 µm)) and 1 part of Epoxysilane KBM-403 manufactured by Shin-Etsu Chemical Co., Ltd. 110 parts of spherical silica ("SOC2" (average particle size 0.5 µm) manufactured by Admatechs Co., Ltd. and 1 part of epoxy silane KBM-403 manufactured by Shin-Etsu Chemical Co., Ltd.) 110 parts An adhesive film was obtained in the same manner as in Example 3 except that the varnish of the thermosetting resin composition changed to the part was used.

<Comparative Example 5>
In Example 1, phenoxy resin (“YX6954BH30” (weight average molecular weight 38000) manufactured by Japan Epoxy Resin Co., Ltd.) was mixed into a mixed solvent having a mass ratio of 1: 1 to methyl ethyl ketone (hereinafter abbreviated as “MEK”) and cyclohexanone. 20 parts of a dissolved resin solution having a non-volatile content of 30% by mass and a polyvinyl butyral resin solution (“KS-1” (glass transition temperature 105 ° C., weight average molecular weight: 27000) manufactured by Sekisui Chemical Co., Ltd.) of ethanol and toluene An adhesive film was obtained in exactly the same manner as in Example 1 except that a varnish of a thermosetting resin composition excluding 12 parts (resin solution having a solid content of 15% dissolved in a mixed solvent having a mass ratio of 1: 1) was used. It was.

<Comparative Example 6>
In Example 1, phenoxy resin (“YX6954BH30” (weight average molecular weight 38000) manufactured by Japan Epoxy Resin Co., Ltd.) was mixed into a mixed solvent having a mass ratio of 1: 1 to methyl ethyl ketone (hereinafter abbreviated as “MEK”) and cyclohexanone. 20 parts of a dissolved resin solution having a nonvolatile content of 30% by mass and polyvinyl butyral resin solution (“KS-1” manufactured by Sekisui Chemical Co., Ltd. (glass transition temperature 105 ° C., weight average molecular weight: 27000)) are masses of ethanol and toluene. Except 12 parts of a resin solution having a solid content of 15% dissolved in a mixed solvent having a ratio of 1: 1), a polyimide resin solution (“Unidic V-8000” (weight average molecular weight 20000) manufactured by DIC Corporation) was used instead. A crocodile of a thermosetting resin composition to which 20 parts of a 40 mass% ethyl diglycol acetate solution) is added Except using the in the same manner as in Example 1 to obtain an adhesive film.

<Comparative Example 7>
In Comparative Example 6, 20 parts of the polyimide resin solution was changed to 20 parts of a rubber-modified polyamide resin solution (DMP solution of “BPAM-260” (weight average molecular weight 70000) manufactured by Nippon Kayaku Co., Ltd.). An adhesive film was obtained in the same manner as in Comparative Example 6 except that the varnish of the thermosetting resin composition thus obtained was used.

<Comparative Example 8>
In Comparative Example 6, except for using a varnish of a thermosetting resin composition in which 20 parts of a polyimide resin solution was changed to 20 parts of a polyimide resin (a DMF solution having a non-volatile content of 40% by mass of “Matrimid 5218US” manufactured by Bantico Co., Ltd.). Produced an adhesive film in exactly the same manner as in Comparative Example 6.

<Comparative Example 9>
In Comparative Example 6, 20 parts of a polyimide resin solution was added to MEK / toluene having a nonvolatile content of 12.5% by mass of acrylic acid ester copolymer resin (“SG-70L” (weight average molecular weight 80000) manufactured by Nagase ChemteX Corporation). Solution) An adhesive film was obtained in the same manner as in Comparative Example 6 except that the varnish of the thermosetting resin composition changed to 40 parts was used.

<Melt viscosity measurement>
The melt viscosity of the resin composition layer in the adhesive films prepared in Examples and Comparative Examples was measured. Using UBM Model Rheosol-G3000, using a parallel plate with a resin amount of 1 g and a diameter of 18 mm, starting temperature from 60 ° C. to 200 ° C., heating rate of 5 ° C./min, measurement The melt viscosity was measured under the measurement conditions of a temperature interval of 2.5 ° C. and a vibration of 1 Hz / deg.

<Lamination test>
The adhesive films produced in the examples and comparative examples were subjected to L (line: wiring width) / S (space) with a conductor thickness of 35 μm using a batch type vacuum pressure laminator MVLP-500 (trade name, manufactured by Meiki Co., Ltd.). : Interval width) = 160/160 μm was laminated on a comb-like conductor pattern. Lamination was performed by reducing the pressure for 30 seconds to a pressure of 13 hPa or less, and then pressing at 100 ° C. and a pressure of 0.74 MPa for 30 seconds. The presence or absence of voids in the resin composition layer after lamination was confirmed. The PET film was peeled from the laminated adhesive film, and the resin composition was cured under curing conditions at 180 ° C. for 30 minutes to form an insulating layer. The value of the unevenness difference (Rt: maximum peak-to-valley) between the conductor and other portions in the insulating layer is determined using a non-contact type surface roughness meter (WYKO NT3300 manufactured by Beeco Instruments Inc.), VSI contact mode, The value was obtained by a numerical value obtained with a 10 × lens with a measurement range of 1.2 mm × 0.91 mm.
In addition, there is no generation of voids after lamination, and the difference in unevenness between the conductor and other portions is less than 5 μm, and no void is generated after lamination, but the unevenness difference between the conductor and other portions is 5 μm. The case above was evaluated as Δ, and the case where void occurred after lamination was evaluated as ×.

<Preparation of peel strength and Ra value measurement sample>
(1) Underlayer treatment of inner layer circuit board Both sides of a glass cloth base epoxy resin double-sided copper-clad laminate (copper foil thickness 18 μm, substrate thickness 0.3 mm, Matsushita Electric Works R5715ES) on which an inner layer circuit is formed The copper surface was roughened by immersing in CZ8100 (a surface treatment agent containing an azoles copper complex and an organic acid) manufactured by MEC Co., Ltd.
(2) Lamination of Adhesive Film The adhesive films produced in the examples and comparative examples were laminated on both sides of the inner circuit board using a batch type vacuum pressure laminator MVLP-500 (trade name, manufactured by Meiki Co., Ltd.). . Lamination was performed by reducing the pressure for 30 seconds to a pressure of 13 hPa or less, and then pressing at 100 ° C. and a pressure of 0.74 MPa for 30 seconds.
(3) Curing of resin composition (3-1) Examples 1 and 2 and Comparative Examples 1 to 3 and 5 to 9
The PET film was peeled off from the laminated adhesive film, and the resin composition was cured under curing conditions at 170 ° C. for 30 minutes to form an insulating layer.
(3-2) Example 3 and Comparative Example 4
The PET film was peeled from the laminated adhesive film, and the resin composition was cured under curing conditions at 100 ° C. for 30 minutes, and further at 180 ° C. for 30 minutes to form an insulating layer.
(4) Roughening treatment (4-1) Examples 1 and 2 and Comparative Examples 1 to 3 and 5 to 9
The laminate is immersed in a swelling solution, a swelling dip / seculigand P containing diethylene glycol monobutyl ether, which is a swelling solution, and then concentrated as a roughening solution by Atotech Japan Co., Ltd., Compact P (KMnO). ₄ : 60 g / L, NaOH: 40 g / L aqueous solution), and finally, as a neutralizing solution, immersed in Atotech Japan Co., Ltd. Reduction Sholyshin Securigant P at 40 ° C. for 5 minutes (roughening conditions) : Immersion in swelling liquid at 60 ° C. for 5 minutes, immersion in roughening liquid at 80 ° C. for 20 minutes).
About the laminated board after this roughening process, the surface roughness was measured with the following method.
(4-2) Example 3 and Comparative Example 4
The laminate is immersed in a swelling solution, a swelling dip / seculigand P containing diethylene glycol monobutyl ether, which is a swelling solution, and then concentrated as a roughening solution by Atotech Japan Co., Ltd., Compact P (KMnO). ₄ : 60 g / L, NaOH: 40 g / L aqueous solution), and finally, as a neutralizing solution, immersed in Atotech Japan Co., Ltd. Reduction Sholyshin Securigant P at 40 ° C. for 5 minutes (roughening conditions) : Immersion in swelling liquid at 80 ° C. for 10 minutes, immersion in roughening liquid at 80 ° C. for 20 minutes).
About the laminated board after this roughening process, the surface roughness was measured with the following method.
(5) Plating by semi-additive method In order to form a circuit on the surface of the insulating layer, the inner layer circuit board was immersed in an electroless plating solution containing PdCl ₂ and then immersed in an electroless copper plating solution. After annealing at 150 ° C. for 30 minutes, an etching resist was formed, and after pattern formation by etching, copper sulfate electrolytic plating was performed to form a conductor layer with a thickness of 30 ± 5 μm. Next, annealing was performed at 180 ° C. for 60 minutes. The peel strength of the plated copper was measured for this circuit board.

<Stripping strength of peeled conductor layer (peel strength)>
When the conductor layer of the circuit board is cut into a 10 mm wide and 100 mm long part, this end is peeled off and gripped with a gripper, and 35 mm is peeled off vertically at a speed of 50 mm / min at room temperature. The load of was measured.

<Surface roughness after roughening (Ra value)>
Using a non-contact type surface roughness meter (BYCO Instruments WYKO NT3300), the Ra value was determined by a numerical value obtained by setting the measurement range to 121 μm × 92 μm with a VSI contact mode and a 50 × lens. Moreover, it measured by calculating | requiring the average roughness of 10 points | pieces.

<Evaluation of glass transition temperature (Tg) and linear thermal expansion coefficient>
The adhesive films obtained in Examples and Comparative Examples were heated at 190 ° C. for 90 minutes to thermally cure the resin composition layer. The cured product was cut into a test piece having a width of about 5 mm and a length of about 15 mm, and thermomechanical analysis was performed by a tensile load method using a thermomechanical analyzer manufactured by Rigaku Corporation (Thermo Plus TMA8310). After mounting the test piece on the apparatus, the test piece was measured twice continuously under the measurement conditions of a load of 1 g and a heating rate of 5 ° C./min. In the second measurement, the glass transition temperature and the average linear thermal expansion coefficient from 25 ° C. to 150 ° C. were calculated.
The results are shown in Tables 1 and 2 below.

  From the result of Table 1, since the resin composition which comprises the adhesive film obtained in Examples 1-3 has low melt viscosity, it is excellent in laminating property, and the cured product (insulating layer) is It has a low coefficient of thermal expansion with an average linear thermal expansion coefficient of 35 ppm or less. Moreover, although the insulating layer has low surface roughness, a high peel strength conductor layer having a peel strength of 0.6 kgf / cm or more can be formed. On the other hand, since the adhesive film of Comparative Example 1 uses spherical silica that has not been subjected to surface treatment, the dispersibility of the spherical silica in the resin composition is remarkably poor, and the melt viscosity of the resin composition is also increased. A void was generated, which was not suitable for the insulating layer. Therefore, subsequent evaluation was omitted. The adhesive film of Comparative Example 2 uses a spherical silica whose surface is treated with hexamethyldisilazane, and the adhesive film of Comparative Example 3 is a spherical silica whose surface is treated with imidazole silane and hexamethyldisilazane in this order. However, in either case, since the resin composition does not have sufficient meltability, in the lamination of the resin composition layer on the comb-like conductor pattern, the unevenness difference between the conductor and the other portion The surface of the insulating layer obtained by curing it is larger than 5 μm, and the roughness after the roughening treatment for obtaining a high peel strength conductor layer increases, which is disadvantageous for the formation of fine wiring. there were. In addition, in the adhesive film of Comparative Example 4 using spherical silica subjected only to surface treatment with epoxysilane, the resin composition does not have sufficient meltability, and the resin composition on the comb-like conductor pattern It was difficult to ensure flatness in the lamination of the layers, and the roughness and linear thermal expansion coefficient were inferior to Example 3. Furthermore, in the adhesive film of Comparative Example 5 in which no phenoxy resin and / or polyvinyl acetal resin was used, the resin composition had good laminating properties, but the cured product (insulating layer) had a high peel strength conductor layer. In the adhesive films of Comparative Examples 6 to 9 using a thermoplastic resin other than the phenoxy resin and / or the polyvinyl acetal resin, the resin composition exhibits good laminating properties, but the cured product ( Insulating layer) did not provide low roughness and high peel strength as in Examples 1-3.

Claims (8)

(A) A polyfunctional epoxy resin, (B) a curing agent, (C) a phenoxy resin and / or polyvinyl acetal resin, and (D) an inorganic filler surface-treated with a silazane compound and then surface-treated with a silane coupling agent. a resin composition containing, relative to a non-volatile content 100% by weight of the resin composition, tree fat composition content of Ru 50-80% by mass of the component (D) is a sheet-like fibers consisting of fibers A prepreg impregnated in a substrate . The prepreg according to claim 1, wherein the content of the component (D) is 55 to 75% by mass. The prepreg according to claim 1 or 2, wherein the inorganic filler is silica having an average particle size of 1 µm or less and a maximum particle size of 5 µm or less. The prepreg according to any one of claims 1 to 3, wherein the phenoxy resin and / or the polyvinyl acetal resin has a weight average molecular weight of 8,000 to 150,000. The total content of the components (A) and (B) is 15 to 50% by mass with respect to 100% by mass of the nonvolatile content in the resin composition, and the total of epoxy groups of the epoxy resin present in the resin composition The prepreg according to any one of claims 1 to 4, wherein a ratio of the number to the total number of reactive groups of the epoxy curing agent (epoxy group: reactive group) is 1: 0.4 to 2.0. To a non-volatile content 100% by weight of the resin composition, 1 to 10 mass% content of the component (C), the prepreg according to any one of claims 1 to 5. (C) The weight average molecular weight of the phenoxy resin and / or the polyvinyl acetal resin is 8,000 to 150,000, and the content of the (C) phenoxy resin and / or the polyvinyl acetal resin in the resin composition is a resin. The prepreg according to any one of claims 1 to 6, which is in a range of 1 to 20% by mass with respect to 100% by mass of a nonvolatile content in the composition . The circuit board using the prepreg of any one of Claims 1-7.