JP2000198907A - Flame-retardant epoxy resin composition and production of interlayer adhesive film for printed wiring board and multilayer printed wiring board by using same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an epoxy resin composition improved in flame retardancy, heat resistance, electrical insulation properties, and the ability to firmly adhere to a conductor layer by including a polyfunctional epoxy resin with a roughening component soluble or decomposable in an aqueous oxidizing agent solution, a salt of a basic-nitrogen-containing compound with a polyphosphoric acid, and a curing agent. SOLUTION: This composition is obtained by compounding a polyfunctional epoxy resin with 5-40 wt.% roughening component being soluble or decomposable in an aqueous oxidizing agent solution and being at least one member selected from among a rubber component, an inorganic filler, and an organic filler, 0.2-10 wt.% (in terms of the phosphorus atoms) salt of a basic-nitrogen-containing compound with a polyphosphoric acid, a curing agent in such an amount that the total of the active hydrogen groups is 0.3-1.0 equivalent per equivalent of the epoxy groups of the epoxy resin, and, optionally, a cure accelerator. The composition is applied to an inner layer circuit board having been subjected to patterning and dried at 50-150 deg.C for 5-30 min. The surface of the resin layer is roughened with an aqueous oxidizing agent solution to form fine irregularities, and a conductor layer is formed on the roughened surface to obtain a multilayer printed board.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multilayer printed wiring board in which conductive circuit layers and insulating layers are alternately built up, and simultaneously satisfies good flame retardancy, heat resistance, electrical insulating properties and adhesive strength of the conductive layers. Flame-retardant epoxy resin composition and interlayer adhesive film for printed wiring board using the same,
The present invention relates to a multilayer printed wiring board and a method for manufacturing the same.

[0002]

2. Description of the Related Art In recent years, as electronic devices have become smaller and higher in performance, printed wiring boards have been increasing in density and multilayered. As a method of manufacturing such a high-density multilayer printed wiring board, an insulating resin layer is alternately laminated on a conductor layer without using a conventional copper foil, a prepreg and a laminating press method using an inner layer material, and the wiring is formed by a via hole. The development of build-up type multilayer printed wiring boards for connection is being actively conducted.
As a method of forming a via hole in a build-up type printed wiring board, a photo via method in which a photosensitive resin is used for an insulating resin layer and exposure and development, and a method in which a via hole is formed by laser processing using a thermosetting resin are studied. ing. In addition, in a printed wiring board using a conventional lamination press method, a through-hole plating process is included, so that the thickness of the outer layer conductor is increased by adding the copper thickness of the copper plating to the copper foil, making it difficult to form a fine pattern. However, in the build-up method, the conductor layer can be formed directly on the insulating resin, so that the fine pattern can be easily formed. Taking advantage of these features, build-up type printed wiring boards are lightweight and compact video cameras,
It is expected to be used not only as motherboards for portable information devices and mobile phones, but also as substrates for semiconductor packages and MCMs.

[0003] On the other hand, interest in global environmental issues and safety for the human body has been increasing, and in addition to flame retardancy, products with less harmfulness and higher safety have been demanded for electric and electronic devices. I have. Electric and electronic devices are not only flame retardant, but also reduce harmful gases and smoke. Accordingly, similar characteristics are required for a printed wiring board on which components are mounted and a substrate material thereof. In order to satisfy this requirement, brominated epoxy resins having tetrabromobisphenol A in the resin skeleton are widely used in glass epoxy copper-clad laminates and prepregs. Printed wiring boards manufactured using such substrate materials not only generate harmful hydrogen bromide gas when burned, but if not properly incinerated, may generate dioxins and cause environmental problems. ing. From such a viewpoint, an epoxy resin composition using a red phosphorus flame retardant as a non-halogen flame retardant, and a glass epoxy copper clad laminate have been developed. (For example, JP-A-9-207271,
Japanese Patent Application Laid-Open No. 9-307240 discloses a method for manufacturing a multilayer wiring board using a photosensitive resin containing red phosphorus as an interlayer insulating material as an insulating material used in the build-up method. However, the red phosphorus used in these is a dangerous substance itself, and there is a problem in work safety, and there are restrictions on handling of the composition and the laminate.

[0004]

SUMMARY OF THE INVENTION In view of the above circumstances, the present invention shows good flame retardancy without containing halogen,
Provided is a flame-retardant epoxy resin composition which simultaneously satisfies heat resistance, electrical insulation properties and adhesive strength of a conductor layer, and an interlayer adhesive film for a printed wiring board using the same. Furthermore, it is another object of the present invention to provide a multilayer printed wiring board which can cope with an increase in wiring density, is excellent in heat resistance and electrical insulation, and a method for manufacturing the same.

[0005]

Means for Solving the Problems In order to solve the above problems, the present inventors have conducted intensive studies, and as a result, have shown the following flame-retardant epoxy resin composition, an interlayer adhesive film for a printed wiring board using the same, and a multilayer film. It has been found that the printed wiring board has extremely excellent performance, and the present invention has been completed. That is, the present invention comprises (A) a polyfunctional epoxy resin, (B) a roughening component soluble or decomposed in an aqueous solution of an oxidizing agent, (C) a salt of a basic nitrogen-containing compound and polyphosphoric acid, and (D) a curing agent as an essential component. A flame-retardant epoxy resin composition comprising the following flame-retardant epoxy resin composition as an essential component and an interlayer adhesive film for a printed wiring board using the same.

The present invention also relates to a method for manufacturing a printed wiring board using the flame-retardant epoxy resin composition of the present invention. (1) A step of forming a resin layer on an inner layer material on which an inner layer circuit is formed and thermosetting (2) Resin A step of forming a roughened surface having irregularities on the surface of the layer by roughening treatment with an aqueous solution of an oxidizing agent; and (3) a step of forming a conductor layer on the roughened surface. Plate manufacturing method.

Further, the present invention relates to a method for manufacturing a printed wiring board using the interlayer adhesive film for a printed wiring board of the present invention. (1) A support base film is laminated on an inner layer material on which an inner layer circuit is formed under pressure and heating conditions. (2) Step of forming a roughened surface with irregularities by roughening treatment with an aqueous solution of an oxidizing agent on the surface of the resin layer (3) Forming a conductor layer on the roughened surface A method for manufacturing a multilayer printed wiring board, comprising the steps of:

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The flame-retardant epoxy resin composition used in the present invention is composed of (A) a polyfunctional epoxy resin, (B) a roughening component soluble or decomposed in an aqueous solution of an oxidizing agent, (C) a basic component. It comprises a nitrogen-containing compound and a salt of polyphosphoric acid (D) as a curing agent as essential components. Each component is described below.

Specific examples of the polyfunctional epoxy resin (A) include a phenol novolak type epoxy resin (eg, Epicoat 152, 15 manufactured by Yuka Shell Epoxy Co., Ltd.).
4), cresol novolak type epoxy resin (e.g., Epicron N-673, N-69 manufactured by Dainippon Ink and Chemicals, Inc.)
5), bisphenol A type epoxy resin, bisphenol F type epoxy resin, (Example: Yuka Shell Epoxy Co., Ltd.)
Epicoat 828EL, 807) Bisphenol S type epoxy resin (example: Epicron EXA-1514 manufactured by Dainippon Ink & Chemicals, Inc.), biphenyl type epoxy resin (example: Epicoat YX-4 manufactured by Yuka Shell Epoxy Co., Ltd.)
000) naphthalene type epoxy resin (eg, HP-4032 manufactured by Dainippon Ink and Chemicals, Inc.), dicyclopentadiene type epoxy resin (example: HP- manufactured by Dainippon Ink and Chemicals, Inc.)
7200) N-glycidyl type epoxy resin, epoxy resin such as alicyclic epoxy resin, triglycidyl isocyanurate, phenoxy resin from the viewpoint of imparting flexibility (eg, YP-50S manufactured by Toto Kasei Co., Ltd.), urethane modified Known epoxy resins such as an epoxy resin and a rubber-modified epoxy resin can be used.

As the roughening component soluble or decomposed in the aqueous solution of the oxidizing agent (B), at least one roughening component selected from a rubber component, an inorganic filler and an organic filler can be used. . Examples of the rubber component include polybutadiene rubber (R-45HT manufactured by Idemitsu Petrochemical, G-1000 manufactured by Nippon Soda, etc.), various polybutadiene derivatives such as urethane-modified, maleated, acrylated, methacrylized, and epoxy-modified (Idemitsu Petrochemical R -45 EPI,
Nippon Soda's BN-1015, GQ-1000, etc.), core-shell rubber fine particles (Takeda Pharmaceutical's staphyloid,
Zeon F351, etc.), or a fine particle rubber-dispersed epoxy resin (YR-570, YR-528, Toto Kasei) in which fine particle rubber is dispersed in an epoxy resin in advance. Examples of inorganic fillers include calcium carbonate,
Magnesium carbonate, magnesium oxide, aluminum hydroxide, magnesium hydroxide and the like can be used. In particular, when aluminum hydroxide or magnesium hydroxide is used, an effect can be expected in imparting flame retardancy. Examples of the organic filler include pre-cured epoxy resin powder, crosslinked acrylic polymer fine particles, and those obtained by heat-curing amino resins such as melamine resins, guanamine resins, urea resins, and their alkyl etherified resins, and then pulverizing them. No. These roughening components in the resin composition,
It is important that it is in the range of 5 to 40% by weight. If it is less than 5% by weight, the roughening properties are insufficient, and if it exceeds 40% by weight, the electrical properties, chemical resistance and heat resistance are reduced.

(C) As a salt of a basic nitrogen-containing compound and polyphosphoric acid, ammonium polyphosphate, melamine polyphosphate, melamine polyphosphate, melam polyphosphate, surface-coated with triazine derivatives such as ammonium polyphosphate and melamine; These double salts can also be used. Further, these surface-coated products can be used. water resistant,
From the viewpoint of chemical resistance and electrical insulation, it is desirable to use a salt of a basic nitrogen-containing compound and polyphosphoric acid, which are hardly soluble in water. Preferred examples thereof include salts of polyphosphoric acid with at least one basic nitrogen-containing compound selected from melamine polyphosphate, melam polyphosphate, and melem polyphosphate. It is important that these components have a phosphorus atom content of 0.2 to 10% by weight, preferably 0.5 to 5% by weight in the resin composition. If it is less than 0.2% by weight, the flame retardancy is insufficient, and if it exceeds 10% by weight, the chemical resistance and the heat resistance decrease.

As the curing agent (D), known and commonly used ones such as amine-based, guanidine-based, imidazole-based, phenol-based curing agents and epoxy adducts thereof can be used. These can be used alone or in combination of two or more.

Specific examples of the curing accelerator (component (E)) in which a curing accelerator can be used if necessary in addition to the above-mentioned curing agents include tertiary amines, quaternary ammonium salts,
Examples thereof include imidazole compounds or organic acid salts thereof, phosphine compounds, guanamine compounds, and boron trifluoride compounds, and are preferably imidazole compounds and phosphine compounds. These can be used alone or in combination of two or more.

The content of the components (D) and (E) is as follows:
(A) Epoxy group in epoxy resin used for component 1.
It is desirable that the sum of the active hydrogen groups in the components (D) and (E) be in the range of 0.3 to 1.0 with respect to 0. If the addition amount is less than this, the heat resistance decreases, and if it is more than this, unreacted active hydrogen groups remain, which is not preferable because the insulation property is reduced.

The flame-retardant epoxy resin composition can be applied to a substrate by a known method such as screen printing, curtain coating, roll coating, spray coating and the like. In each application method, if necessary, known and publicly used fillers and additives such as fillers, solvents, defoamers, thixotropic agents, pigments, dyes and the like can be used.

A multilayer printed wiring board using the flame-retardant epoxy resin composition of the present invention and a method for producing the same will be described. The flame-retardant epoxy resin composition of the present invention is applied to a pattern-processed inner circuit board by a known method such as screen printing, curtain coating, roll coating, spray coating, and dried. The drying conditions vary depending on the solvent used, but are selected in the range of 50 to 150 ° C. for 5 to 30 minutes. Thereafter, heat curing is performed as necessary, and a predetermined through-hole and / or via-hole is opened with a laser and / or a drill. If necessary, the surface of the resin composition is treated with a roughening agent to form fine irregularities. Next, the conductor layer is formed by dry and / or wet plating to produce a multilayer printed wiring board. The conditions for thermosetting are 12
It is selected within the range of 10 to 90 minutes at 0 to 200 ° C. Specific examples of the roughening agent that can be used as the roughening agent include oxidizing agents such as dichromate, permanganate, ozone, hydrogen peroxide / sulfuric acid, and nitric acid, and N-methyl-2-pyrrolidone. , N, N-dimethylformamide, methoxypropanol, and the like, an alkaline aqueous solution such as caustic soda and potassium hydroxide, an acidic aqueous solution such as sulfuric acid and hydrochloric acid, and various plasma treatments. These processes may be used in combination. After forming an anchor having fine irregularities on the surface of the resin composition as necessary, a conductor layer is formed by dry plating such as vapor deposition, sputtering, or ion plating and / or wet plating such as electroless plating or electrolytic plating. At this time, a plating resist having a pattern opposite to that of the conductor layer may be formed, and the conductor layer may be formed only by electroless plating. After the conductor layer is formed in this manner, by annealing for 10 to 60 minutes at a temperature higher than the glass transition temperature of the cured product of the thermosetting resin composition, the curing of the thermosetting resin progresses, The peel strength of the layer can be further improved.

When the flame-retardant epoxy resin composition is used as an interlayer adhesive film for a printed wiring board, it has a weight average molecular weight of 5,000 to 5,000 to improve mechanical strength and flexibility and to facilitate handling. A binder polymer in the range of 100,000 "is required. If the weight average molecular weight is less than 5,000, the effect of improving mechanical strength and flexibility is not exhibited, and if it exceeds 100,000, the solubility in organic solvents and the compatibility with the epoxy resin become poor, so that it cannot be used. The amount added is preferably in the range of 5 to 50% by weight. If less than 5% by weight, mechanical strength,
The effect of improving the flexibility is not exhibited, and if it exceeds 50% by weight, the heat fluidity becomes poor, which is not preferable. The binder polymer also has the effect of preventing cissing on the support film in the drying step during film production. Specifically, a phenoxy resin, a polyacryl resin, a polyimide resin, a polyamideimide resin, a polycyanate resin, a polyester resin, a polyphenylene ether resin and the like can be mentioned, and these can be used in combination of two or more.

The interlayer adhesive film for a printed wiring board of the present invention is obtained by applying a resin varnish dissolved in a predetermined organic solvent using a base film as a support, and then drying the solvent by heating and / or blowing with hot air to obtain a resin composition which is solid at room temperature. It can be manufactured as a product. Examples of the support base film include polyolefins such as polyethylene, polypropylene, and polyvinyl chloride; polyesters such as polyethylene terephthalate; polycarbonate; and release paper, copper foil, and metal foils such as aluminum foil. The thickness of the supporting base film is generally from 10 to 150 μm. The support film may be subjected to a release treatment in addition to the mud treatment and the corona treatment. As the organic solvent, usually a solvent, for example, acetone, methyl ethyl ketone,
Ketones such as cyclohexanone, ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate, acetic acid esters such as carbitol acetate, cellosolve, cellosolves such as butyl cellosolve, carbitol, carbitols such as butyl carbitol, In addition to aromatic hydrocarbons such as toluene and xylene, dimethylformamide, dimethylacetamide, N-methylpyrrolidone and the like can be used alone or in combination of two or more. The thus obtained interlayer adhesive film of the present invention is stored as it is or by further laminating a protective film such as a support film on the other surface of the resin composition, winding it into a roll shape, and storing.

Next, a multilayer printed wiring board using the interlayer adhesive film for a printed wiring board of the present invention and a method of manufacturing the same will be described. When bonding the interlayer adhesive film of the present invention to the patterned inner layer circuit board, if the protective film is present, the protective film is removed, and a normal temperature solid resin composition is added from the support base film side. Laminate under pressure and heat. As the inner circuit board, a glass epoxy, metal board, polyester board, polyimide board, thermosetting polyphenylene ether board, or the like can be used, and the circuit surface may be roughened in advance. The lamination may be a batch type or a continuous type with a roll under reduced pressure, and it is preferable to laminate both sides simultaneously. The above laminating conditions vary depending on the hot melt viscosity of the room temperature solid resin composition of the present invention and the used inner layer circuit board. Generally, the crimping temperature is 70 to 150 ° C and the crimping pressure is 1 to 10 kgf / cm2. And laminate under reduced pressure of 20 mmHg or less. After lamination, the support base film is peeled off after cooling to around room temperature. Then, if necessary, heat-cured, and laser and / or
Alternatively, a hole is formed by a drill, and if necessary, the surface of the resin composition is treated with a roughening agent to form fine irregularities. Next, the conductor layer is formed by dry and / or wet plating to produce a multilayer printed wiring board. The conditions for heat curing are selected in the range of 120 to 200 ° C. for 10 to 90 minutes. Specific examples of the roughening agent that can be used as the roughening agent include oxidizing agents such as dichromate, permanganate, ozone, hydrogen peroxide / sulfuric acid, and nitric acid, and N-methyl-2-pyrrolidone. , N, N-dimethylformamide, methoxypropanol, and the like, an alkaline aqueous solution such as caustic soda and potassium hydroxide, an acidic aqueous solution such as sulfuric acid and hydrochloric acid, and various plasma treatments. These processes may be used in combination. After forming an anchor having fine irregularities on the surface of the resin composition as necessary, a conductor layer is formed by dry plating such as vapor deposition, sputtering, or ion plating and / or wet plating such as electroless plating or electrolytic plating. At this time, a plating resist having a pattern opposite to that of the conductor layer may be formed, and the conductor layer may be formed only by electroless plating. After the conductor layer is thus formed, the thermosetting resin composition is annealed at a temperature higher than the glass transition temperature of the cured product for 10 to 60 minutes, whereby the curing of the thermosetting resin progresses, The peel strength of the layer can be further improved.

Hereinafter, the present invention will be described in detail with reference to examples.

[0021]

Examples 1 to 5 Flame-retardant epoxy resin compositions were prepared with the compositions shown in the examples of Table 1 (the numerical values are parts by weight). For the preparation of the flame-retardant epoxy resin composition of each Example, each resin and each component were mixed with a dissolver, uniformly dispersed with a three-roll mill, and then adjusted with a diluting solvent to adjust the viscosity. These resin compositions are applied on a circuit-formed substrate by screen printing, and dried at 120 ° C. for 15 minutes.
After curing at 30 ° C. for 30 minutes, the mixture was swelled with a mixture of an aqueous alkaline solution and a solvent, and then treated with an aqueous alkaline permanganate solution, followed by a reducing agent, and subjected to a roughening agent treatment.
Thereafter, a copper-clad laminate having a copper thickness of 35 microns was produced by electroless copper plating or electrolytic copper plating. Annealing treatment was performed at 150 ° C. for 60 minutes to produce a copper-clad laminate wiring board and evaluated.

[0022]

Example 6 Compositions shown in Examples of Table 1 (numerical parts are parts by weight)
Was used to prepare a flame-retardant epoxy resin composition. Regarding the preparation of the flame-retardant epoxy resin composition, each resin and each component were uniformly mixed in a methyl ethyl ketone solvent to prepare a resin varnish. The varnish is applied on a 30 μm-thick polyethylene terephthalate (hereinafter referred to as PET) film using a roller coater so that the thickness after drying becomes 50 μm, and dried at 80 to 100 ° C. for 10 minutes to form a printed wiring board. An interlayer adhesive film was obtained. This film was bent at 180 degrees for evaluation of flexibility, but there was no abnormality such as crack in the resin portion. An interlayer adhesive film for a printed wiring board was simultaneously laminated on both sides of the circuit-formed inner layer circuit board by a vacuum laminator. 150 ° C
For 30 minutes to obtain a laminated substrate. Thereafter, predetermined through holes, via holes, and the like were drilled with a drill and a laser. After swelling with a mixture of an alkaline aqueous solution and a solvent, the mixture was treated with an alkaline permanganate aqueous solution and subsequently with a reducing agent, and subjected to a roughening agent treatment. afterwards,
A multilayer laminate having a copper thickness of 35 microns was produced by electroless copper plating and electrolytic copper plating. Annealing was performed at 150 ° C. for 60 minutes, and a 4-layer printed wiring board on which a circuit was formed by a subtractive method was prepared and evaluated. . The obtained printed wiring board was immersed in a solder bath at 260 ° C. for 60 seconds, and the solder heat resistance was observed. No abnormality was found. Also,
In the thermal shock test (-55 ° C to 125 ° C, 500 cycles), no abnormality was found in the connection of the through hole and the via hole.

[0023]

Comparative Examples 1 to 3 Epoxy resin compositions having the compositions shown in Comparative Examples in Table 1 were prepared. Regarding the preparation of the epoxy resin composition of each comparative example, an epoxy resin composition was prepared with the composition shown in Table 1 (the numerical values are parts by weight). Weigh each resin and each component,
After mixing and uniformly dispersing with a three-roll mill, the viscosity was adjusted with a diluting solvent to prepare a mixture. For the preparation and evaluation samples of the epoxy resin compositions of Comparative Examples, Examples 1 to 6 were used.
Compliant.

[0024]

[Table 1]

The results are shown in Table 2. As is clear from Examples 1 to 6, when the flame-retardant epoxy resin composition of the present invention was used, there was no problem in flame retardancy, heat resistance and insulation properties, and no peeling after annealing and good peeling Strength was obtained, and there was no problem such as blistering in the solder heat test. On the other hand, in the case of Comparative Example 1, there was no problem in flame retardancy and insulation properties, but swelling occurred in the solder heat resistance test because it did not contain a roughening component. In the case of Comparative Example 2, there was no problem in heat resistance and electric characteristics because it did not contain a flame retardant, but the sample burned in the combustion test. Comparative Example 3 was the same as Comparative Example 2 except that the brominated epoxy resin and antimony trioxide were used as flame retardants, and had the same characteristics.

[0026]

[Table 2]

[0027]

As described above, the flame-retardant epoxy resin composition of the present invention, that is, (A) a polyfunctional epoxy resin, (B) a roughening component which is soluble or decomposed in an aqueous solution of an oxidizing agent, (C) a basic component By using a flame-retardant epoxy resin composition containing a nitrogen-containing compound and a salt of polyphosphoric acid (D) as a hardening component as an essential component and an interlayer adhesive film for a printed wiring board using the same, good flame-retardancy without halogen is obtained. While showing the nature,
A flame-retardant epoxy resin composition which simultaneously satisfies heat resistance, electrical insulation properties, and adhesive strength of a conductor layer, and an interlayer adhesive film for a printed wiring board using the same was obtained. Further, it is possible to provide a multilayer printed wiring board which can cope with a high density of wirings and is excellent in heat resistance and electrical insulation and a method for manufacturing the same.

Continued from the front page F-term (reference) 4J002 AC032 BG022 CC162 CC182 CC192 CD001 CD021 CD051 CD061 CD071 CD141 CP002 DE076 DE146 DE236 DH057 EJ008 EN008 ER028 EU118 FD148 FD150 FD202 FD206 FD207 GQ01 5E346 AA12 AA15 AA23GG DD DD203 GG27 HH11 HH16

Claims (6)

[Claims] An essential component comprising: (A) a polyfunctional epoxy resin; (B) a roughening component soluble or decomposed in an aqueous solution of an oxidizing agent; (C) a salt of a basic nitrogen-containing compound and polyphosphoric acid; and (D) a curing agent. Flame-retardant epoxy resin composition 2. The flame-retardant epoxy resin composition (B)
The flame retardant according to claim 1, wherein the roughening component soluble or decomposed in the aqueous solution of the oxidizing agent is at least one kind of a roughening component selected from a rubber component, an inorganic filler, and an organic filler. Epoxy resin composition (C) The salt of a basic nitrogen-containing compound and polyphosphoric acid is a salt of at least one basic nitrogen-containing compound and polyphosphoric acid selected from melamine polyphosphate, melam polyphosphate and melem polyphosphate. The flame-retardant epoxy resin composition according to claim 1 or 2, 4. The method according to claim 1, wherein the support base film is formed on a support base film.
Interlayer adhesive film for printed wiring boards formed from the flame-retardant epoxy resin described 5. The step of (1) forming a resin layer on the inner layer material on which the inner layer circuit is formed and thermally curing the flame-retardant epoxy resin composition according to any one of claims 1 to 3, and (2) oxidizing the surface of the resin layer. Forming a roughened surface in an uneven shape by a roughening agent treatment with an aqueous solution of an agent; and (3) forming a conductor layer on the roughened surface. 6. The interlayer adhesive film for a printed wiring board according to claim 4 is laminated on the inner layer material on which (1) the inner layer circuit is formed under pressure and heating conditions, and after peeling off the supporting base film, if necessary. Step of thermosetting (2) Step of forming a roughened surface on the surface of the resin layer by roughening treatment with an aqueous solution of an oxidizing agent (3) Step of forming a conductor layer on the roughened surface Of manufacturing a multilayer printed wiring board.