JP5500073B2 - Film with metal film - Google Patents

Description

  The present invention relates to a film with a metal film and an adhesive film with a metal film. Moreover, it is related with the manufacturing method of circuit boards, such as a multilayer printed wiring board using these films, and the manufacturing method of a metal-clad laminated board.

  Conventionally, a method of transferring a metal film layer such as a copper film onto an adherend as a plating seed layer has been attempted. For example, in Patent Documents 1 and 2, a film with a metal film in which a copper film is formed on a support by vapor deposition or the like through a release layer is prepared, and the copper film of the film with the metal film is formed on an inner circuit board. A method is disclosed in which a conductor layer is formed by plating or the like on a transferred copper film after being transferred to the resin composition layer surface or the prepreg surface. Patent Document 3 discloses an adhesive film in which a copper film is formed directly on a support by vapor deposition or the like, and a resin composition layer is formed thereon.

  However, a thin metal film of a film with a metal film is likely to crack due to a difference in coefficient of thermal expansion with that of the release layer. Further, when the thickness of the release layer is insufficient, cracks occur in the metal film layer at the stage after the film with the metal film is manufactured. When these cracks occur, it becomes difficult to form a uniform metal film layer using a film with a metal film. Moreover, such a problem is the same also in the adhesive film with a metal film which formed the curable resin composition layer on the metal film layer of the film with a metal film.

JP 2004-230729 A JP 2002-324969 A JP-A-9-296156

  An object of the present invention is to prevent the occurrence of cracks in the metal film layer during the production of the film with the metal film and the adhesive film with the metal film, and further, the metal film layer when thermosetting the thermosetting resin composition on the adherend. It is to provide the film capable of preventing the occurrence of cracks.

  In the film with a metal film and the adhesive film with a metal film, the present inventors solve the above problem by setting the arithmetic average roughness of the surface of the support layer on which the release layer is formed to a certain value or less. The present invention was completed.

That is, the present invention includes the following contents.
[1] A film with a metal film in which a release layer is formed on the surface of a support layer having an arithmetic average roughness (Ra) of 50 nm or less, and a metal film layer is formed on the release layer.
[2] The film with a metal film according to the above [1], wherein the release layer has a thickness of 0.1 to 5 μm.
[3] The film with a metal film according to [1] or [2], wherein the metal film layer has a thickness of 50 nm to 5000 nm.
[4] With a metal film according to any one of [1] to [3], wherein the metal film layer is formed by one or more methods selected from a vapor deposition method, a sputtering method, and an ion plating method. the film.
[5] The surface of the release layer that adheres to at least the metal film layer is formed of one or more water-soluble polymers selected from water-soluble cellulose resins, water-soluble polyester resins, and water-soluble acrylic resins. The film with a metal film according to any one of [1] to [4].
[6] The film with a metal film according to any one of [1] to [5], wherein the support layer is a plastic film.
[7] The film with a metal film according to any one of [1] to [5], wherein the support layer is a polyethylene terephthalate film.
[8] The film with a metal film according to any one of [1] to [7], wherein the thickness of the support layer is 10 μm to 70 μm.
[9] A film with a metal film according to any one of the above [1] to [8] is applied to an adherend having at least a surface layer made of a curable resin composition so that the metal film layer is in contact with the surface of the adherend. A method for transferring a metal film layer, the method comprising: laminating and laminating and curing the curable resin composition; and peeling the support layer.
[10] The film with a metal film according to any one of the above [5] to [8] is applied to an adherend having at least a surface layer made of a curable resin composition so that the metal film layer is in contact with the surface of the adherend. A method for transferring a metal film layer, comprising: a step of laminating and curing a curable resin composition; a step of peeling a support layer; and a step of dissolving and removing a release layer present on the metal film layer with an aqueous solution.
[11] The film with a metal film according to any one of the above [1] to [8] is applied to the curable resin composition layer on the inner circuit board so that the metal film layer is in contact with the surface of the curable resin composition layer. A method for manufacturing a circuit board, comprising: a step of stacking layers and curing a curable resin composition layer; and a step of peeling a support layer.
[12] The film with a metal film according to any one of [5] to [8] above is applied to the curable resin composition layer on the inner circuit board so that the metal film layer is in contact with the surface of the curable resin composition layer. A method for manufacturing a circuit board, comprising: a step of laminating and curing a curable resin composition layer; a step of peeling a support layer; and a step of dissolving and removing a release layer present on a metal film layer with an aqueous solution.
[13] The method according to [11] or [12] above, further comprising a step of forming a conductor layer on the metal film layer by plating.
[14] The method according to any one of [11] to [13] above, wherein the curable resin composition layer is composed of a prepreg in which a sheet-like substrate made of fibers is impregnated with the curable resin composition.
[15] The film with a metal film according to any one of the above [1] to [8], wherein the metal film layer is a prepreg on one side or both sides of a single prepreg or a multilayer prepreg obtained by stacking a plurality of prepregs. A method for producing a metal-clad laminate, comprising: a step of heating and pressurizing in contact with a surface; and a step of peeling a support layer.
[16] The film with a metal film according to any one of the above [5] to [8], wherein the metal film layer is a prepreg on one side or both sides of a single prepreg or a multilayer prepreg obtained by stacking a plurality of prepregs. A method for producing a metal-clad laminate, comprising a step of heating and pressurizing so as to be in contact with a surface, a step of peeling a support layer, and a step of dissolving and removing a release layer present on a metal film layer with an aqueous solution.
[17] An adhesive film with a metal film, wherein a curable resin composition layer is further formed on the metal film layer of the film according to any one of [1] to [8].
[18] A step of laminating and laminating the adhesive film with a metal film according to the above [17] on the inner layer circuit board so that the curable resin composition layer is in contact with the inner layer circuit board, a step of curing the curable resin composition layer, And a method for producing a circuit board, comprising a step of peeling the support layer.
[19] An adhesive film with a metal film in which a curable resin composition layer is further formed on the metal film layer of the film according to any one of [5] to [8] above, the curable resin composition layer Dissolving the release layer existing on the metal film layer with an aqueous solution, stacking the inner layer circuit board in contact with the inner circuit board, laminating the curable resin composition layer, peeling the support layer, and the metal film layer A method for manufacturing a circuit board, comprising a step of removing.
[20] The method according to [18] or [19] above, further comprising a step of forming a conductor layer on the metal film layer by plating.

  The “circuit board” referred to in the present invention is not particularly limited as long as it has an insulating layer and a conductor layer on which a circuit is formed, and includes various circuit boards such as a multilayer printed wiring board and a flexible printed wiring board. Further, among the circuit boards, in particular, when referred to as “inner circuit board”, pattern processing was performed on one side or both sides of a glass epoxy board, metal board, polyester board, polyimide board, BT resin board, thermosetting polyphenylene ether board (circuit). An intermediate product that has a conductor layer (formed) and on which an insulating layer and a conductor layer are to be formed when a circuit board is manufactured.

  In the film with a metal film and the adhesive film with a metal film of the present invention, the arithmetic average roughness of the surface of the support layer on which the release layer is formed is not more than a certain value, so that cracks in the metal film layer during the production of the film Generation of cracks in the metal film layer when the thermosetting resin composition on the adherend is thermoset can also be prevented. Therefore, it is possible to manufacture a circuit board such as a multilayer printed wiring board, a metal-clad laminate, and the like that are highly reliable and advantageous for miniaturization by using these films.

It is a photograph of the metal film layer surface where a crack does not exist. It is a photograph of the metal film layer surface where a crack exists.

In the film with a metal film of the present invention, a release layer is formed on the surface of the support layer having an arithmetic average roughness (Ra) of 50 nm or less, and the metal film layer is formed on the release layer.
[Support layer]
The support constituting the support layer is a self-supporting film or sheet, and a plastic film is preferably used. Examples of the plastic film include a polyethylene terephthalate film, a polyethylene naphthalate film, a polyimide film, a polyamideimide film, a polyamide film, a polytetrafluoroethylene film, and a polycarbonate film, and a polyethylene terephthalate film and a polyethylene naphthalate film are preferable. An inexpensive polyethylene terephthalate film is particularly preferred.

  The upper limit value of the thickness of the support layer is preferably 70 μm, more preferably 60 μm, still more preferably 50 μm, and still more preferably 40 μm, from the viewpoint of ensuring practicality from the viewpoint of cost. The lower limit of the thickness of the support layer is preferably 10 μm, preferably 15 μm, from the viewpoint of preventing the support layer from being deteriorated in handleability and peelability and preventing the formation of a smooth metal film layer. Is more preferable, and 20 μm is even more preferable. The surface of the support in contact with the curable resin composition layer may be subjected to a surface treatment such as a corona treatment. Further, the surface of the support that does not contact the curable resin composition layer may be subjected to surface treatment such as mat treatment or corona treatment.

  In the present invention, at least the arithmetic average roughness (Ra) of the surface of the support layer on the side where the release layer is formed needs to be 50 nm or less (that is, 0 to 50 nm). Preferably it is 40 nm or less, More preferably, it is 35 nm or less, More preferably, it is 30 nm or less. When the arithmetic average roughness (Ra) exceeds this range, cracks in the metal film layer tend to occur when a film with a metal film is produced. The lower limit of the arithmetic average roughness (Ra) is not particularly limited, but is preferably 0.1 nm or more and more preferably 0.5 nm or more from the viewpoint of practicality of the support. The arithmetic average roughness of the surface of the support layer on the side where the release layer is not formed is not particularly limited, but when the film with a metal film is wound up into a roll shape, the surface is in contact with the metal film layer, Since there is a possibility of causing a crack, it is preferable to be within the same range as described above from the viewpoint of eliminating the fear of the occurrence of such a problem. The method for setting the arithmetic average roughness (Ra) of the support layer surface to 50 nm or less is not particularly limited, and methods known to those skilled in the art can be used. For example, a plastic film such as a polyethylene terephthalate film is generally provided with a surface irregularity by containing a filler in order to facilitate winding up into a roll after production, and reducing the filler content. As a result, the Ra value can be lowered. Commercially available supports can also be used, such as T60 (Toray Industries, polyethylene terephthalate film, Ra = 22 nm), A4100 (Toyobo, polyethylene terephthalate film, smooth surface side Ra = 12 nm), Q83 ( And Teijin DuPont Films, polyethylene naphthalate film, smooth surface side Ra = 32 nm). The arithmetic average roughness (Ra value) can be measured by using a known method, for example, using a device such as a non-contact type surface roughness meter (such as WYKO NT3300 manufactured by Becoins Instruments). .

[Release layer]
In the present invention, a release layer is formed on the support surface having an arithmetic average roughness (Ra) of 50 nm or less.
The release layer can be formed using a fluororesin, a polyolefin resin, a polyvinyl alcohol resin, an acrylic resin, a polyester resin, a melamine resin, cellulose, or the like, but is uniform on the adherend by the film of the present invention. From the viewpoint of forming the metal film layer, it is preferably formed of one or more selected from a water-soluble cellulose resin, a water-soluble acrylic resin, and a water-soluble polyester resin. When these water-soluble polymers are employed as a release layer, the support layer can be peeled between the support layer and the release layer after curing of the curable resin composition as the adherend, and then the metal film layer Since the release layer remaining on the substrate is easily removed with an aqueous solution, a metal film having excellent uniformity can be formed on the adherend. Among these, a water-soluble cellulose resin and a water-soluble polyester resin are more preferable, and a water-soluble cellulose resin is particularly preferable. Usually, any water-soluble polymer is used alone in the water-soluble polymer release layer, but two or more water-soluble polymers can be mixed and used. The water-soluble polymer release layer is usually formed as a single layer, but may have a multilayer structure formed of two or more layers in which the water-soluble polymers used are different. In order to improve the peelability between the water-soluble polymer release layer and the support layer, another release layer such as a silicone resin, an alkyd resin, or a fluororesin may be present on the support layer. That is, when a water-soluble polymer is applied to the release layer, it is sufficient that at least the surface of the release layer that adheres to the metal film layer is formed of the water-soluble polymer. A two-layer structure of a water-soluble polymer release layer and another release layer, etc., so that the surface to be bonded with the metal film layer is formed of a water-soluble polymer only with the release layer. can do. When the release layer is formed of only a water-soluble polymer, peeling of the support between the support layer and the release layer is performed at the interface between the support and the release layer, and the release layer is an alkyd resin or the like. When it consists of two layers of another release layer and the water-soluble polymer release layer, it is carried out at the interface between the other release layer and the water-soluble polymer release layer. In addition, as a mold release agent of alkyd resin, AL-5 (made by Lintec Corporation) is mentioned.

  The layer thickness of the release layer is preferably from 0.1 μm to 5 μm (0.1 to 5 μm). More preferably, they are 0.1 micrometer or more and 3 micrometers or less, More preferably, they are 0.1 micrometer or more and 2 micrometers or less, More preferably, they are 0.1 micrometer or more and 1 micrometer or less, More preferably, they are 0.2 micrometer or more and 1 micrometer or less. The “layer thickness” here is the thickness when the release layer is a single layer, and the total thickness of the multilayer when it is a multilayer. For example, as described above, when the release layer is composed of a water-soluble polymer release layer and other release layers such as silicone resin, alkyd resin, and fluorine resin, the total of these release layers The layer thickness is set in the above range. When the layer thickness is too thick, when the curable resin composition layer is thermally cured, the metal film layer tends to crack due to the difference in thermal expansion coefficient between the metal film layer and the release layer. On the other hand, when the layer thickness is too thin, the peelability of the support layer may be lowered.

  The method for forming the release layer is not particularly limited, and a known lamination method such as hot pressing, hot roll lamination, extrusion lamination, coating / drying of a coating solution can be adopted, but a simple and highly uniform layer can be formed. From the viewpoint of easy formation, a method of applying and drying a coating liquid containing a material used for the release layer is preferable.

(Water-soluble cellulose resin)
The “water-soluble cellulose resin” as used in the present invention refers to a cellulose derivative that has been subjected to a treatment for imparting water-solubility to cellulose, and preferred examples include cellulose ether and cellulose ether ester.

  Cellulose ether is an ether formed by conversion of one or more hydroxyl groups present in one or more anhydroglucose repeat units of a cellulose polymer to provide one or more ether linking groups to the cellulose polymer. The group is an alkyl group (optionally substituted with one or more substituents selected from a hydroxyl group, a carboxyl group, an alkoxy group (1 to 4 carbon atoms) and a hydroxyalkoxy group (1 to 4 carbon atoms). C1-C4) is mentioned. Specifically, hydroxyalkyl groups (1 to 4 carbon atoms) such as 2-hydroxyethyl, 2-hydroxypropyl, 3-hydroxypropyl; 2-methoxyethyl, 3-methoxypropyl, 2-methoxypropyl, 2-ethoxy Alkoxy (C1-C4) alkyl group (C1-C4) such as ethyl; hydroxyalkoxy (C1-C4) such as 2- (2-hydroxyethoxy) ethyl or 2- (2-hydroxypropoxy) propyl ) Alkyl groups (1 to 4 carbon atoms), carboxyalkyl groups such as carboxymethyl (1 to 4 carbon atoms), and the like. The ether linking group in the polymer molecule may be a single species or a plurality of species. That is, it may be a cellulose ether having a single type of ether linking group or a cellulose ether having a plurality of types of ether linking groups.

  Specific examples of the cellulose ether include methyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, hydroxybutyl methyl cellulose, hydroxyethyl ethyl cellulose, carboxymethyl cellulose and water-soluble salts thereof (for example, alkali metal salts such as sodium salts). Can be mentioned.

  In addition, although the average number of moles of the ether group substituted per unit glucose ring in cellulose ether is not specifically limited, 1-6 are preferable. The molecular weight of cellulose ether is preferably 20000 to 60000 in weight average molecular weight.

  On the other hand, a cellulose ether ester is an ester formed between one or more hydroxyl groups present in cellulose and one or more organic acids or reactive derivatives thereof, thereby forming an ester linking group in the cellulose ether. is there. The “cellulose ether” herein is as described above, and the “organic acid” includes an aliphatic or aromatic carboxylic acid (having 2 to 8 carbon atoms), and the aliphatic carboxylic acid is acyclic (branched) Or unbranched) or cyclic, saturated or unsaturated. Specifically, examples of the aliphatic carboxylic acid include substituted or unsubstituted acyclic aliphatic dicarboxylic acids such as acetic acid, propionic acid, butyric acid, valeric acid, malonic acid, succinic acid, glutaric acid, fumaric acid, and maleic acid; Examples include acyclic hydroxy-substituted carboxylic acids such as glycolic acid or lactic acid; acyclic aliphatic hydroxy-substituted di- or tri-carboxylic acids such as malic acid, tartaric acid, and citric acid. The aromatic carboxylic acid is preferably an aryl carboxylic acid having 14 or less carbon atoms, and includes an aryl group such as a phenyl or naphthyl group having one or more carboxyl groups (for example, 1, 2 or 3 carboxyl groups). Aryl carboxylic acids are particularly preferred. The aryl group is substituted with one or more (for example, 1, 2 or 3) groups which may be the same or different and selected from hydroxy, alkoxy having 1 to 4 carbon atoms (for example, methoxy) and sulfonyl. May be. Preferable examples of the aryl carboxylic acid include phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid (1,2,4-benzenetricarboxylic acid) and the like.

  Where the organic acid has one or more carboxyl groups, preferably only one carboxyl group of the acid forms an ester linkage to the cellulose ether. For example, in the case of hydroxypropylmethylcellulose succinate, one carboxyl group of each succinate group forms an ester linkage with cellulose and the other carboxyl group is present as a free acid. An “ester linking group” is formed by reaction of cellulose or cellulose ether with a suitable organic acid as described above or a reactive derivative thereof. Suitable reactive derivatives include, for example, acid anhydrides such as phthalic anhydride.

  The ester linking group in the polymer molecule may be a single type or a plurality of types. That is, it may be a cellulose ether ester having a single type of ester linking group or a cellulose ether ester having a plurality of types of ester linking groups. For example, hydroxypropyl methylcellulose acetate succinate is a mixed ester of hydroxypropyl methylcellulose having both succinate and acetate groups.

Suitable cellulose ether esters are hydroxypropylmethylcellulose or esters of hydroxypropylcellulose, specifically hydroxypropylmethylcellulose acetate, hydroxypropylmethylcellulose succinate, hydroxypropylmethylcellulose acetate succinate, hydroxypropylmethylcellulose phthalate, hydroxypropylmethylcellulose Trimellitate, hydroxypropyl methylcellulose acetate phthalate, hydroxypropyl methylcellulose acetate trimellitate, hydroxypropyl cellulose acetate phthalate, hydroxypropyl cellulose butyrate phthalate, hydroxypropyl cellulose acetate phthalate succinate and B hydroxypropyl cellulose acetate trimellitate succinate, etc. These may be used alone or in combination.
Among these, hydroxypropylmethylcellulose phthalate, hydroxypropylmethylcellulose acetate succinate, and hydroxypropylmethylcellulose acetate phthalate are preferable.

  In addition, the average number of moles of the ester group substituted per unit glucose ring in the cellulose ether ester is not particularly limited, but is preferably 0.5 to 2. The molecular weight of the cellulose ether ester is preferably 20000 to 60000 in weight average molecular weight.

  Cellulose ethers and cellulose ether esters are well known in the art, and can be obtained by reacting an etherifying agent and an esterifying agent in accordance with a conventional method using natural cellulose (pulp) as a raw material. May be used. “HP-55”, “HP-50” (both hydroxypropylmethylcellulose phthalate), “60SH-06” (hydroxypropylmethylcellulose) manufactured by Shin-Etsu Chemical Co., Ltd. and the like can be mentioned.

(Water-soluble polyester resin)
The “water-soluble polyester resin” as used in the present invention is synthesized by an ordinary polycondensation reaction using a polyvalent carboxylic acid or an ester-forming derivative thereof and a polyhydric alcohol or an ester-forming derivative thereof as main raw materials. It is a polyester resin made of a substantially linear polymer, and has a hydrophilic group introduced in the molecule or at the molecular end. Here, examples of the hydrophilic group include an organic acid group such as a sulfo group, a carboxyl group, and a phosphoric acid group or a salt thereof, and a sulfonic acid group or a salt thereof, a carboxylic acid group or a salt thereof is preferable. As the water-soluble polyester resin, those having a sulfo group or a salt thereof and / or a carboxyl group or a salt thereof are particularly preferable.

  Representative examples of the polyvalent carboxylic acid component of the polyester resin include terephthalic acid, isophthalic acid, phthalic acid, phthalic anhydride, 2,6-naphthalenedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, adipic acid, and the like. These may be used alone or in combination of two or more. In addition to the above-mentioned various compounds, hydroxycarboxylic acids such as p-hydroxybenzoic acid and unsaturated carboxylic acids such as maleic acid, fumaric acid or itaconic acid may be used in combination in small amounts.

  Representative examples of the polyhydric alcohol component of the polyester resin include ethylene glycol, 1,4-butanediol, neopentyl glycol, diethylene glycol, dipropylene glycol, 1,6-hexane glycol, 1,4-cyclohexane methanol, and xylylene. Examples thereof include glycol, dimethylolpropionic acid, glycerin, trimethylolpropane, and poly (tetramethylene oxide) glycol. These may be used alone or in combination of two or more.

  The introduction of a hydrophilic group into the molecule or the molecular end of the polyester resin may be carried out by a known and conventional method, but an ester-forming compound (such as an aromatic carboxylic acid compound or a hydroxy compound) containing a hydrophilic group is copolymerized. Embodiments are preferred.

  For example, when introducing a sulfonate group, 5-sulfonic acid sodium isophthalic acid, 5-sulfonic acid ammonium isophthalic acid, 4-sulfonic acid sodium isophthalic acid, 4-methylsulfonic acid ammonium isophthalic acid, 2-sulfonic acid sodium terephthalic acid It is preferable to copolymerize one or more selected from potassium isophthalic acid 5-sulfonate, potassium isophthalic acid 4-sulfonate, potassium terephthalic acid 2-sulfonate, and the like.

  In addition, when introducing a carboxylic acid group, for example, one or two kinds selected from trimellitic anhydride, trimellitic acid, pyromellitic anhydride, pyromellitic acid, trimesic acid, cyclobutanetetracarboxylic acid, dimethylolpropionic acid and the like. It is preferable to copolymerize the above, and after the copolymerization reaction, the carboxylate group can be introduced into the molecule by neutralization with an amino compound, ammonia or an alkali metal salt.

  The molecular weight of the water-soluble polyester resin is not particularly limited, but the weight average molecular weight is preferably 10,000 to 40,000. If the weight average molecular weight is less than 10,000, the layer formability tends to decrease, and if it exceeds 40000, the solubility tends to decrease.

  In the present invention, a commercially available product can be used as the water-soluble polyester resin, and “Plus Coat Z-561” (weight average molecular weight: about 27000) and “Plus Coat Z-565” manufactured by Kyoyo Chemical Industry Co., Ltd. (Weight average molecular weight: about 25000).

(Water-soluble acrylic resin)
The “water-soluble acrylic resin” referred to in the present invention is an acrylic resin that is dispersed or dissolved in water by containing a carboxyl group-containing monomer as an essential component.

  More preferably, the acrylic resin is a monomer component in which a carboxyl group-containing monomer and a (meth) acrylic ester are essential, and if necessary, other unsaturated monomers as monomer components. Acrylic polymer.

  In the above monomer component, carboxyl group-containing monomers include (meth) acrylic acid, maleic acid, fumaric acid, crotonic acid, itaconic acid, citraconic acid, maleic anhydride, monomethyl maleate, monobutyl maleate, itacone Examples thereof include monomethyl acid and monobutyl itaconate, and one or more of these can be used. Among these, (meth) acrylic acid is preferable.

  In addition, (meth) acrylic acid esters include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, N-pentyl (meth) acrylate, n-hexyl (meth) acrylate, n-heptyl (meth) acrylate, n-octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (meth) acrylic acid Nonyl, (meth) acrylic acid decyl, (meth) acrylic acid dodecyl, alkyl methacrylate having 1 to 18 carbon atoms such as stearyl (meth) acrylate, and one of these Two or more kinds can be used.

  Other unsaturated monomers include aromatic alkenyl compounds, vinyl cyanide compounds, conjugated diene compounds, halogen-containing unsaturated compounds, hydroxyl group-containing monomers, and the like. Examples of the aromatic alkenyl compound include styrene, α-methylstyrene, p-methylstyrene, p-methoxystyrene, and the like. Examples of the vinyl cyanide compound include acrylonitrile and methacrylonitrile. Examples of the conjugated diene compound include butadiene and isoprene. Examples of the halogen-containing unsaturated compound include vinyl chloride, vinylidene chloride, perfluoroethylene, perfluoropropylene, and vinylidene fluoride. As the hydroxyl group-containing monomer, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl acrylate, Examples thereof include 4-hydroxybutyl methacrylate and α-hydroxymethylethyl (meth) acrylate. These can use 1 type (s) or 2 or more types.

  As will be described later, in the present invention, the release layer is preferably formed by a method of applying and drying a coating liquid containing water-soluble cellulose, water-soluble polyester or water-soluble acrylic resin on a support. When a water-soluble acrylic resin is used, the coating solution can be used in an emulsion form or an aqueous solution form.

  When a water-soluble acrylic resin is used in the form of an emulsion, a core-shell type emulsion is preferable, and in the core-shell type emulsion, it is important that a carboxyl group is present in the shell of the core-shell particle. And an acrylic resin containing a (meth) acrylic acid ester.

  Commercially available dispersions (emulsions) of such core-shell particles can be used, such as Joncryl 7600 (Tg: about 35 ° C.), 7630A (Tg: about 53 ° C.), 538J (Tg: about 66 ° C.), 352D (Tg: about 56 ° C.) (both manufactured by BASF Japan Ltd.).

  When the water-soluble acrylic resin is used in the form of an aqueous solution, the acrylic resin is an acrylic resin containing a carboxyl group-containing monomer and a (meth) acrylic acid ester, and it is important that the molecular weight is relatively low. Therefore, it is preferable that the weight average molecular weight is 1000 to 50000. If the weight average molecular weight is less than 1000, the layer-forming property tends to decrease. If the weight average molecular weight exceeds 50000, the adhesion to the support layer is high. It becomes the tendency for the peelability of the support body layer after hardening to fall.

  As such an aqueous solution of a water-soluble acrylic resin, a commercial product can be used, and examples include Jonkrill 354J (manufactured by BASF Japan Ltd.).

  In addition, the emulsion and the aqueous solution of water-soluble acrylic resin are easy to be thinned because the emulsion has a higher molecular weight. Accordingly, a water-soluble acrylic resin emulsion is preferred.

<Metal film layer>
In the film with a metal film used in the present invention, as the metal film layer, in addition to simple metals such as gold, platinum, silver, copper, cobalt, chromium, nickel, titanium, tungsten, aluminum, zinc, iron, tin, and indium Any type of metal such as a solid solution (alloy) of two or more types of metals can be used as appropriate. Among them, from the viewpoints of cost, versatility to which a vapor deposition method or a sputtering method can be applied, electrical conductivity, etc. Nickel, titanium, nickel / chromium alloy, aluminum, zinc, copper / nickel alloy, copper / titanium alloy, gold, silver and copper are preferable, chromium, nickel, titanium, nickel / chromium alloy, aluminum, zinc, gold, silver and copper Is more preferable, and copper is particularly preferable. Further, the metal film layer may be a single layer or may be composed of two or more layers. For example, in the system in which thermal degradation (decomposition) of the resin is a concern due to diffusion of the copper layer to the curable resin composition layer during thermosetting of the curable resin composition layer, if necessary, on the copper layer A chromium layer, a nickel-chromium alloy layer, or a titanium layer can be provided. That is, after the copper layer is formed on the water-soluble polymer release layer, a chromium layer, a nickel / chromium alloy layer, or a titanium layer can be further formed.

  The layer thickness of the metal film layer is preferably 50 nm to 5000 nm, more preferably 50 nm to 3000 nm, more preferably 100 nm to 2000 nm, and particularly preferably 100 nm to 1000 nm. When the layer thickness is too small, it becomes easy to be affected by the unevenness of the surface of the support layer and the difference in the coefficient of thermal expansion from the release layer, and the problem of cracks tends to become apparent. Further, in a desmear process or the like in the production of a circuit board, the metal film layer may be dissolved by acid cleaning or the like, and the surface of the insulating layer may be roughened. On the other hand, if the layer thickness is too large, the problem of cracks tends to be reduced, but it takes a long time to form a metal film by vapor deposition, sputtering, ion plating, etc., making it practical in terms of cost. It tends to be inferior. The total layer thickness in the case of the two-layer structure of the copper layer / chromium layer, nickel / chromium alloy layer or titanium layer as described above is the same as above, and the chromium layer, nickel / chromium layer or titanium layer has the same thickness. The thickness is preferably 5 nm to 100 nm, more preferably 5 nm to 50 nm, particularly preferably 5 nm to 30 nm, and most preferably 5 nm to 20 nm. In addition, the measuring method of the layer thickness of a metal layer is not specifically limited, A well-known method is employable. For example, it can be measured using a fluorescent X-ray film thickness meter (SII NanoTechnology Co., Ltd., SFT9455 series, etc.). The layer thickness of each layer such as a metal layer and a release layer can also be measured by a scanning electron microscope (SEM) photograph of the layer cross section.

The metal film layer is preferably formed by one or more methods selected from a vapor deposition method, a sputtering method and an ion plating method, and particularly preferably formed by a vapor deposition method and / or a sputtering method. These methods can be used in combination, but usually any one method is used alone.
A known method can be used for the sputtering method. For example, a support having a release layer is placed in a vacuum vessel, an inert gas such as argon is introduced, a DC voltage is applied, and the ionized inert gas is applied. A gas can be collided with a target metal, and a film can be formed on the release layer by the struck metal.
As a vapor deposition method (vacuum vapor deposition method), a known method can be used. For example, a support having a release layer is placed in a vacuum vessel, and a metal is heated and evaporated to form a film on the release layer. be able to.
As the ion plating method, a known method can be used. For example, a support having a release layer is placed in a vacuum vessel, and the metal is heated and evaporated in a glow discharge atmosphere. Film formation can be performed on the layer.
In the process of cooling to room temperature after forming the metal film, if the release layer thickness is small and the arithmetic mean roughness (Ra) value of the support surface on which the release layer is provided is large, the metal film will crack. Is likely to occur.

[Curable resin composition layer]
The curable resin composition layer in the adhesive film can be used without any particular limitation as long as the cured product has sufficient hardness and insulation properties, such as epoxy resin, cyanate ester resin, phenol resin, bismaleimide-triazine. A composition in which at least the curing agent is blended with a curable resin such as a resin, a polyimide resin, an acrylic resin, or a vinylbenzyl resin is used. Among these, a composition in which the curable resin is an epoxy resin is preferable, and a composition containing at least (a) an epoxy resin, (b) a thermoplastic resin, and (c) a curing agent is more preferable.

  (A) Epoxy resin includes 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, alicyclic epoxy Resin, aliphatic chain epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol A novolak type epoxy resin, epoxy resin having butadiene structure, diglycidyl etherified product of bisphenol, diglycidyl etherified product of naphthalenediol, Examples thereof include glycidyl etherified products of phenols, diglycidyl etherified products of alcohols, and alkyl-substituted products, halides and hydrogenated products of these epoxy resins. It is. These epoxy resins may be used alone or in combination of two or more.

  Among these, the epoxy resin has a bisphenol A type epoxy resin, a naphthol type epoxy resin, a naphthalene type epoxy resin, a biphenyl type epoxy resin, and a butadiene structure from the viewpoint of heat resistance, insulation reliability, and adhesion to a metal film. Epoxy resins are preferred. Specifically, liquid bisphenol A type epoxy resin (“Epicoat 828EL” manufactured by Japan Epoxy Resin Co., Ltd.), naphthalene type bifunctional epoxy resin (“HP4032”, “HP4032D” manufactured by Dainippon Ink & Chemicals, Inc.), Naphthalene-type tetrafunctional epoxy resin (“HP4700” manufactured by Dainippon Ink and Chemicals, Inc.), naphthol-type epoxy resin (“ESN-475V” manufactured by Tohto Kasei Co., Ltd.), epoxy resin having a butadiene structure (Daicel Chemical Industries ( "PB-3600" manufactured by Co., Ltd.), epoxy resins having a biphenyl structure ("NC3000H", "NC3000L" manufactured by Nippon Kayaku Co., Ltd., "YX4000" manufactured by Japan Epoxy Resin Co., Ltd.), and the like.

  (B) The thermoplastic resin is blended for the purpose of imparting appropriate flexibility to the cured composition, such as phenoxy resin, polyvinyl acetal resin, polyimide, polyamideimide, polyethersulfone, polysulfone. Etc. These may be used alone or in combination of two or more. The thermoplastic resin is preferably blended in a proportion of 0.5 to 60% by weight, more preferably 3 to 50% by weight when the nonvolatile component of the curable resin composition is 100% by weight. When the blending ratio of the thermoplastic resin is less than 0.5% by weight, since the resin composition viscosity is low, it tends to be difficult to form a uniform curable resin composition layer, and when it exceeds 60% by weight, Since the viscosity of the resin composition becomes too high, embedding in the wiring pattern on the inner layer circuit board tends to be difficult.

  Specific examples of the phenoxy resin include FX280 and FX293 manufactured by Toto Kasei Co., Ltd., YX8100, YL6954, and YL6974 manufactured by Japan Epoxy Resin Co., Ltd.

  The polyvinyl acetal resin is preferably a polyvinyl butyral resin. Specific examples of the polyvinyl acetal resin include: Denki 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.

  Specific examples of polyimide include polyimide “Rika Coat SN20” and “Rika Coat PN20” manufactured by Shin Nippon Rika Co., Ltd. Also, a linear polyimide obtained by reacting a bifunctional hydroxyl group-terminated polybutadiene, a diisocyanate compound and a tetrabasic acid anhydride (as described in JP 2006-37083 A), a polysiloxane skeleton-containing polyimide (JP 2002-2002). And modified polyimides such as those described in JP-A No. 12667 and JP-A No. 2000-319386.

  Specific examples of the polyamideimide include polyamideimides “Vilomax HR11NN” and “Vilomax HR16NN” manufactured by Toyobo Co., Ltd. In addition, modified polyamideimides such as polysiloxane skeleton-containing polyamideimides “KS9100” and “KS9300” manufactured by Hitachi Chemical Co., Ltd. may be mentioned.

  Specific examples of polyethersulfone include polyethersulfone “PES5003P” manufactured by Sumitomo Chemical Co., Ltd.

  Specific examples of the polysulfone include polysulfone “P1700” and “P3500” manufactured by Solvay Advanced Polymers Co., Ltd.

  (C) As a curing agent, an amine curing agent, a guanidine curing agent, an imidazole curing agent, a phenol curing agent, a naphthol curing agent, an acid anhydride curing agent, or an epoxy adduct or microencapsulated one thereof. And cyanate ester resins. Of these, phenol-based curing agents, naphthol-based curing agents, and cyanate ester resins are preferable. In addition, in this invention, a hardening | curing agent may be 1 type, or may use 2 or more types together.

  Specific examples of phenol-based curing agents and naphthol-based curing agents include MEH-7700, MEH-7810, MEH-7851 (Maywa Kasei Co., Ltd.), NHN, CBN, GPH (Nippon Kayaku Co., Ltd.), SN170, SN180, SN190, SN475, SN485, SN495, SN375, SN395 (manufactured by Tohto Kasei Co., Ltd.), LA7052, LA7054, LA3018, LA1356 (manufactured by Dainippon Ink & Chemicals, Inc.), and the like.

  Specific examples of the cyanate ester resin include 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 A bifunctional cyanate resin such as dimethylphenyl) methane, 1,3-bis (4-cyanatephenyl-1- (methylethylidene)) benzene, bis (4-cyanatephenyl) thioether, bis (4-cyanatephenyl) ether, Phenol novolac, cle Polyfunctional cyanate resin derived from Runoborakku etc. These cyanate resins and partially triazine of prepolymer. Commercially available cyanate ester resins include phenol novolac type polyfunctional cyanate ester resins (“Lonza Japan Co., Ltd.“ PT30 ”, cyanate equivalent 124) and some or all of bisphenol A dicyanate are triazines and trimers The prepolymer ("BA230" manufactured by Lonza Japan Co., Ltd., cyanate equivalent 232), and the like.

  (A) In the case of a phenolic curing agent or a naphthol curing agent, the blending ratio of the epoxy resin and (c) curing agent is such that the phenolic hydroxyl group equivalent of these curing agents is 0.4 to 1 with respect to the epoxy equivalent 1 of the epoxy resin. A ratio of 2.0 is preferable, and a ratio of 0.5 to 1.0 is more preferable. In the case of a cyanate ester resin, the ratio at which the cyanate equivalent is 0.3 to 3.3 with respect to the epoxy equivalent 1 is preferable, and the ratio at which 0.5 to 2 is more preferable. When the reactive group equivalent ratio is outside this range, the mechanical strength and water resistance of the cured product tend to be lowered.

  In addition to the (c) curing agent, (d) a curing accelerator can be further blended in the curable resin composition. Examples of such curing accelerators include imidazole compounds and organic phosphine compounds, and specific examples include 2-methylimidazole and triphenylphosphine. (D) When using a hardening accelerator, it is preferable to use at 0.1 to 3.0 weight% with respect to an epoxy resin. In the case of using a cyanate ester resin as an epoxy resin curing agent, an organometallic compound conventionally used as a curing catalyst in a system in which an epoxy resin composition and a cyanate compound are used together for the purpose of shortening the curing time. May be added. 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 10 to 500 ppm, preferably 25 to 200 ppm in terms of metal with respect to the cyanate ester resin.

  In addition, the curable resin composition may contain (e) an inorganic filler in order to reduce the thermal expansion of the composition after curing. Examples of the inorganic filler include silica, alumina, mica, mica, silicate, barium sulfate, magnesium hydroxide, and titanium oxide. Silica and alumina are preferable, and silica is particularly preferable. The inorganic filler preferably has an average particle size of 3 μm or less and more preferably 1.5 μm or less from the viewpoint of insulation reliability. The content of the inorganic filler in the curable resin composition is preferably 20 to 60% by weight, more preferably 20 to 50% by weight when the nonvolatile component of the curable resin composition is 100% by weight. is there. When the content of the inorganic filler is less than 20% by weight, the effect of lowering the thermal expansion coefficient tends not to be sufficiently exhibited. When the content of the inorganic filler exceeds 60% by weight, the mechanical strength of the cured product decreases. It becomes a tendency to do.

  In the curable resin composition, other components can be blended as necessary. Other components include organic phosphorus flame retardants, organic nitrogen-containing phosphorus compounds, nitrogen compounds, silicone flame retardants, flame retardants such as metal hydroxides, fillers such as silicon powder, nylon powder and fluorine powder, , Thickeners such as Benton, silicone-based, fluorine-based, polymer-based antifoaming agents or leveling agents, imidazole-based, thiazole-based, triazole-based, silane-based coupling agents such as silane coupling agents, phthalocyanine blue, Colorants such as phthalocyanine green, iodin green, disazo yellow, and carbon black can be used.

  The curable resin composition layer may be a prepreg obtained by impregnating the above-described curable resin composition in a sheet-like reinforcing base made of fibers. As the fiber of the sheet-like reinforcing substrate, those commonly used as prepreg fibers, such as glass cloth and aramid fiber, can be used. The prepreg can be formed by impregnating a curable resin composition by a sheet-like reinforcing base material hot melt method or a solvent method and semi-curing by heating. In addition, the hot melt method, without dissolving the resin composition in an organic solvent, once coated the resin composition on the resin composition and good peelable coated paper, and laminate it on a sheet-like reinforcing substrate, Or it is the method of manufacturing a prepreg by coating directly with a die coater. The solvent method is a method in which a sheet-like reinforcing base material is immersed in a varnish obtained by dissolving a resin composition in an organic solvent, the varnish is impregnated into the sheet-like reinforcing base material, and then dried.

  The thickness of the curable resin composition layer varies depending on the thickness of the conductor layer of the adherend (inner layer circuit board), but is preferably 10 to 150 μm, more preferably 15 from the viewpoint of insulation reliability between layers. ˜80 μm.

  The adhesive film with a metal film can be produced by forming a curable resin composition layer on the surface of the metal film layer after the step of forming the metal film layer of the film with the metal film. A known method can be used as a method for forming the curable resin composition layer. For example, a resin varnish in which a resin composition is dissolved in an organic solvent is prepared, and this resin varnish is formed into a metal film using a die coater or the like. It can be produced by coating on the metal film layer of the attached film and further drying the organic solvent by heating or blowing hot air to form a resin composition layer.

  Examples of organic solvents include ketones such as acetone, methyl ethyl ketone, and cyclohexanone, ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate, acetate esters such as carbitol acetate, and carbitols such as cellosolve and butyl carbitol. Aromatic hydrocarbons such as toluene and xylene, dimethylformamide, dimethylacetamide, N-methylpyrrolidone and the like can be mentioned. 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 of the organic solvent in the resin composition layer is 10% by weight or less, preferably 5% by weight or less. Depending on the amount of organic solvent in the varnish and the boiling point of the organic solvent, a resin composition layer is formed by drying a varnish containing 30 to 60% by weight of an organic solvent at 50 to 150 ° C. for 3 to 10 minutes. .

  Moreover, the adhesive film with a metal film is produced separately from the film with a metal film by producing an adhesive film in which a curable resin composition layer is formed on a support such as the plastic film described above. Can also be produced by a method in which the curable resin composition layer and the metal film layer are bonded together under heating conditions. When the curable resin composition layer is a prepreg, the prepreg can be laminated on the support by a vacuum laminating method. The adhesive film can be produced by a known method.

The film with the metal film and the adhesive film or prepreg are bonded so that the metal film layer of the film with the metal film and the curable resin composition layer of the adhesive film or prepreg face each other. And heat press-bonding with a hot press, a hot roll or the like. The heating temperature is preferably 60 to 140 ° C, more preferably 80 to 120 ° C. The pressure for pressure bonding is preferably 1 to 11 kgf / cm ² (9.8 × 10 ^{4 to} 107.9 × 10 ⁴ N / m ² ), and ^{2 to} 7 kgf / cm ² (19.6 × 10 ^{4 to} 68.6 ×). 10 ⁴ N / m ² ) is particularly preferred.

[Manufacture of circuit boards, etc.]
In the production of the circuit board of the present invention, when an adhesive film with a metal film is used, the curable resin composition layer may be laminated on the inner layer circuit board as an adhesive surface. On the other hand, when a film with a metal film is used, the metal film layer may be stacked so as to be in contact with the surface of the curable resin composition layer present on the inner circuit board.

  A known method can be used to form the curable resin composition layer on the inner layer circuit board. For example, an adhesive film in which the curable resin composition layer is formed on the support layer as described above is used as the inner layer circuit. The curable resin composition layer can be formed on the inner circuit board by laminating on the substrate and removing the support layer by peeling or the like. The lamination conditions for the adhesive film are the same as those for the adhesive film with a metal film, which will be described later.

  In the present invention, when a prepreg is used to manufacture a circuit board, a single-sided or double-sided surface layer of a laminated body in which a single prepreg or a multi-layered prepreg is laminated on an inner circuit board A film with a metal film can be laminated and laminated on a certain prepreg so that the metal film layer is in contact with the prepreg surface. Similarly, a film with a metal film is laminated on one side or both sides of a single prepreg or a multilayer prepreg obtained by stacking a plurality of prepregs so that the metal film layer is in contact with the surface of the prepreg, and heated. The prepreg can be cured by pressurization to produce a metal-clad laminate.

  Lamination | stacking of the adhesive film with a metal film and the film with a metal film laminate | stacks a film on a to-be-adhered body surface by a roll, press press bonding, etc. from the point which is easy to obtain workability | operativity and a uniform contact state. Especially, it is suitable to laminate | stack under reduced pressure by the vacuum laminating method. The lamination method may be a batch method or a continuous method using a roll.

The lamination conditions are generally set such that the pressure is 1 to 11 kgf / cm ² (9.8 × 10 ^{4 to} 107.9 × 10 ⁴ N / m ² ) and the air pressure is 20 mmHg (26.7 hPa) or less. Lamination is preferably performed under reduced pressure.

  The vacuum lamination can be performed using a commercially available vacuum laminator. Commercially available vacuum laminators include: batch type vacuum press laminator MVLP-500 manufactured by Meiki Seisakusho Co., Ltd., vacuum applicator manufactured by Nichigo Morton Co., Ltd., roll dry coater manufactured by Hitachi Industries, Ltd., Hitachi Air Examples include a vacuum laminator manufactured by EC Co., Ltd.

  Further, the curing treatment of the curable resin composition is usually a thermosetting treatment, and the conditions vary depending on the type of the curable resin, but generally the curing temperature is 120 to 200 ° C., and the curing time is 15 to 90. Minutes. In addition, it is preferable from the viewpoint of preventing wrinkles on the surface of the insulating layer to be formed that the curing is performed in a stepwise manner from a relatively low curing temperature to a high curing temperature.

  The support layer after the curing treatment may be peeled mechanically or manually. In addition, when a water-soluble polymer composed of one or more selected from a water-soluble cellulose resin, a water-soluble acrylic resin, and a water-soluble polyester resin is employed as a release layer, the peelability from the plastic film is good. The support layer can be peeled off between the support layer and the release layer, and then the release layer remaining on the metal film layer is simply removed with an aqueous solution, so that the metal film has excellent uniformity without damaging the metal film. Can be formed. The aqueous solution for dissolving and removing the release layer is preferably an alkaline aqueous solution in which sodium carbonate, sodium hydrogen carbonate, sodium hydroxide, potassium hydroxide, etc. are dissolved in water at a concentration of 0.5 to 10% by weight. Etc. The method of dissolving and removing is not particularly limited. For example, after peeling off the support layer, a method of dissolving and removing the inner circuit board by immersing the inner layer circuit board in the aqueous solution, a method of dissolving and removing the aqueous solution by spraying or spraying the aqueous solution, etc. Can be mentioned. The temperature of the aqueous solution is room temperature to 80 ° C., and the treatment time can be 10 seconds to 10 minutes with an aqueous solution such as water immersion or spraying. Examples of the alkaline aqueous solution include an alkaline developer (for example, 0.5 to 2% by weight of sodium carbonate aqueous solution, 25 ° C. to 40 ° C.) used in circuit board manufacture, and a remover for a dry film remover. (For example, 1 to 5% by weight sodium hydroxide aqueous solution, 40 to 60 ° C.), swelling liquid used in the desmear process (for example, alkaline aqueous solution containing sodium carbonate, sodium hydroxide, etc., 60 to 80 ° C.) You can also

  Thereafter, if necessary, a circuit board can be manufactured through blind via formation, through-hole formation, via bottom residue removal (desmear process), conductor layer formation process by plating, and the like. In an insulating layer built up of a multilayer printed wiring board, conduction between layers is generally performed by a blind via. The through hole is generally formed in the core substrate, but the through hole may be formed after the insulating layer is formed. In this case, the same treatment as the desmear process (for example, desmear treatment with an oxidizing agent described later) can be applied to the through hole. A mechanical drill is generally used for forming the through hole, and a laser such as a carbon dioxide laser or a YAG laser is generally used for forming the blind via.

  In order to improve laser workability, a laser absorbing component may be contained in the support layer and / or the release layer. Examples of the laser absorbing component include metal compound powder, carbon powder, metal powder, and black dye. The blending amount of the laser energy absorbing component is 0.05 to 40% by weight, preferably 0.1 to 20% by weight, more preferably 1 to 10% by weight, based on all the components constituting the layer containing the component. is there. For example, when the component is contained in a release layer formed from a water-soluble resin, the total content including the water-soluble resin and the component is set to 100% by weight, and the above content is preferably blended. Examples of the carbon powder include carbon black powder such as furnace black, channel black, acetylene black, thermal black, and anthracene black, graphite powder, and a powder of a mixture thereof. As metal compound powder, titania such as titanium oxide, magnesia such as magnesium oxide, iron oxide such as iron oxide, nickel oxide such as nickel oxide, zinc oxide such as manganese dioxide and zinc oxide, silicon dioxide, Aluminum oxide, rare earth oxide, cobalt oxide such as cobalt oxide, tin oxide such as tin oxide, tungsten oxide such as tungsten oxide, silicon carbide, tungsten carbide, boron nitride, silicon nitride, titanium nitride, aluminum nitride, sulfuric acid Examples thereof include powders of barium, rare earth oxysulfides, or mixtures thereof. Examples of metal powders include silver, aluminum, bismuth, cobalt, copper, iron, magnesium, manganese, molybdenum, nickel, palladium, antimony, silicon, tin, titanium, vanadium, tungsten, zinc, or alloys or mixtures thereof. Is mentioned. Black dyes include azo (monoazo, disazo, etc.) dyes, azo-methine dyes, anthraquinone dyes, quinoline dyes, ketone imine dyes, fluorone dyes, nitro dyes, xanthene dyes, acenaphthene dyes, quinophthalone dyes, aminoketone dyes, methine dyes, perylenes And dyes, coumarin dyes, perinone dyes, triphenyl dyes, triallylmethane dyes, phthalocyanine dyes, incrophenol dyes, azine dyes, or mixtures thereof. The black dye is preferably a solvent-soluble black dye in order to improve dispersibility in a water-soluble resin. These laser energy absorbing components may be used alone or in combination with different types. The laser energy absorbing component is preferably carbon powder, particularly carbon black, from the viewpoint of conversion efficiency of laser energy into heat, versatility, and the like.

  The step of forming the blind via can be performed on the metal film layer. However, when the support is a plastic film, it can be performed on the support layer before the support layer is removed. Moreover, when a release layer remains after removing a support body layer, it can also carry out from on a release layer.

  The desmear process can be performed by a known method such as a dry method such as plasma or a wet method using an oxidizing agent treatment such as an alkaline permanganate solution. The desmear process is a process mainly for removing a via bottom residue generated by blind via formation, and may be performed for the purpose of roughening the via wall surface. In particular, desmear with an oxidizing agent is preferable in that it can remove smear on the bottom of the via and, at the same time, roughen the via wall surface with the oxidizing agent and improve the plating adhesion strength. Further, in the present invention, since the surface of the insulating layer is not roughened, it is advantageous for forming fine wiring, and it is advantageous for shortening the circuit board manufacturing process. The desmear process with an oxidizing agent is usually performed by performing a swelling process with a swelling liquid, a roughening process with an oxidizing agent, and a neutralizing process with a neutralizing liquid in this order. Examples of the swelling liquid include an alkaline solution and a surfactant solution, preferably an alkaline solution. Examples of the alkaline solution include a sodium hydroxide solution and a potassium hydroxide solution. Examples of commercially available swelling liquids include Swelling Dip Securiganth P (Swelling Dip Securiganth P) and Swelling Dip Securiganth SBU (SBU) manufactured by Atotech Japan Co., Ltd. it can. Examples of the oxidizing agent include an alkaline permanganate solution in which potassium permanganate or sodium permanganate is dissolved in an aqueous solution of sodium hydroxide. Roughening treatment with an oxidizing agent such as an alkaline permanganic acid solution is usually performed by subjecting to an oxidizing agent solution heated to 60 to 80 ° C. for 10 to 30 minutes. The concentration of permanganate in the alkaline permanganate solution is generally 5 to 10% by weight. Commercially available oxidizing agents include alkaline permanganic acid solutions such as Concentrate Compact CP, Dosing Solution Securigans P, manufactured by Atotech Japan. The neutralizing solution is preferably an acidic aqueous solution, and a commercially available product is Reduction Solution Securigant P (neutralizing solution) manufactured by Atotech Japan Co., Ltd.

  The metal film layer is used as a conductor layer as it is, or the metal film layer is used as a seed layer, and a metal film layer is further grown thereon by plating (electroless plating and / or electrolytic plating) to form a conductor layer. (At this time, a metal film layer also grows on the inner surface of the via). In general, it is preferable to form a conductor layer on the metal film layer by electrolytic plating. Conductor layer formation by electrolytic plating can be performed by a known method such as a semi-additive method. For example, a plating resist is formed on the metal film layer, and the conductor layer is formed by electrolytic plating. The electrolytic plating layer is preferably copper, and its thickness depends on the desired circuit board design, but is generally 3 to 35 μm, preferably 5 to 30 μm. After electrolytic plating, the plating resist is removed with a plating resist stripping solution such as an alkaline aqueous solution, and then the metal film layer is removed to form a wiring pattern. The metal film layer can be removed by etching with a solution that dissolves the metal forming the metal film layer. Etching is selected according to the selected metal layer. For example, in the case of copper, an acidic etching solution such as an aqueous solution of ferric chloride, an aqueous solution of sodium peroxodisulfate and sulfuric acid, or CF- manufactured by Mec Co., Ltd. An alkaline etching solution such as 6000, E-process-WL manufactured by Meltex Co., Ltd. can be used. In the case of nickel, an etching solution mainly composed of nitric acid / sulfuric acid can be used, and commercially available products include NH-1865 manufactured by MEC, Melstrip N-950 manufactured by Meltex, and the like. Is mentioned.

  EXAMPLES Hereinafter, although an Example is shown and this invention is demonstrated more concretely, this invention is not limited at all by the following Examples. In the following description, “part” means “part by weight”.

Example 1
<Production of film with metal film>
Hydroxypropyl methylcellulose phthalate (manufactured by Shin-Etsu Chemical Co., Ltd. “HP-55”) on T60 (Toray Industries, Inc., Ra = 22 nm) film of polyethylene terephthalate (hereinafter also referred to as “PET”) having a thickness of 38 μm. ) Methyl ethyl ketone (hereinafter abbreviated as “MEK”) and N, N-dimethylformamide (hereinafter abbreviated as “DMF”) 1: 1 solution (solid content 10% by weight) was applied by a die coater, and a hot air drying oven The temperature was raised from room temperature to 140 ° C. at a temperature rising rate of 3 ° C./second to remove the solvent, and a hydroxypropyl methylcellulose phthalate layer having a thickness of about 0.5 μm was formed on the PET film. Next, a copper film layer having a thickness of about 500 nm was formed on the hydroxypropylmethylcellulose phthalate layer by vapor deposition to produce a film with a metal film. No cracks occurred in the metal film layer (copper film layer). FIG. 1 is a photograph of the surface of the metal film layer where no cracks are generated.

<Preparation of adhesive film having curable resin composition layer>
28 parts of liquid bisphenol A type epoxy resin (828EL) and 28 parts of naphthalene type tetrafunctional epoxy resin (HP-4700) were heated and dissolved in a mixed solution of 15 parts of MEK and 15 parts of cyclohexanone with stirring. There, 50 parts of a novolak resin containing a triazine structure which is a phenol-based curing agent (solid phenolic hydroxyl group equivalent 120, “LA7052” manufactured by Dainippon Ink & Chemicals, Inc., MEK solution having a solid content of 60% by weight), 20 parts of phenoxy resin (molecular weight 50000, MEK solution of “E1256” made by Japan Epoxy Resin Co., Ltd. 40 wt%), 0.1 part of curing catalyst (2E4MZ), 55 parts of spherical silica (SOC2), polyvinyl butyral resin 30 parts of a 1: 1 solution of ethanol and toluene with a solid content of 15% by weight (“KS-1” manufactured by Sekisui Chemical Co., Ltd.), an epoxy resin having a butadiene structure (molecular weight: 27000, manufactured by Daicel Chemical Industries, Ltd.) 3 parts of PB-3600 ") were mixed and dispersed uniformly with a high-speed rotary mixer to prepare a resin varnish. The varnish was applied onto a PET film having a thickness of 38 μm using a die coater, the solvent was removed using a hot air drying furnace, and an adhesive film having a thickness of the curable resin composition layer of 40 μm was produced.

<Formation of curable resin composition layer on circuit board>
Roughening is performed on the copper layer of the glass epoxy substrate on which the circuit is formed with an 18 μm-thick copper layer by a CZ8100 (a surface treatment agent containing an azoles copper complex and organic acid (MEC Co., Ltd.)). did. Next, the curable resin composition layer of the adhesive film is brought into contact with the surface of the copper circuit, and the adhesive film is formed into a circuit using a batch type vacuum pressure laminator MVLP-500 (trade name, manufactured by Meiki Seisakusho Co., Ltd.). Laminated on both sides of the substrate. Lamination was performed at a pressure of 13 hPa or less by reducing the pressure for 30 seconds. Next, after cooling to room temperature, the support layer of the adhesive film was peeled off, and curable resin composition layers were formed on both sides of the circuit board.

<Metal film transfer by film with metal film>
The film with metal film prepared above was laminated on the inner circuit board so that the metal film layer (copper film layer) was in contact with the curable resin composition layer. Lamination was performed by laminating on both surfaces of the inner circuit board using a batch type vacuum pressure laminator MVLP-500 (trade name, manufactured by Meiki Seisakusho Co., Ltd.). Lamination was performed by reducing the pressure for 30 seconds to a pressure of 13 hPa or less, and then pressing at a pressure of 7.54 kgf / cm ² for 30 seconds. Thereafter, the curable resin composition layer was cured at 150 ° C. for 30 minutes and further at 180 ° C. for 30 minutes to form an insulating layer (cured product layer). The support PET film was peeled from the insulating layer. The peelability was good and it could be easily peeled by hand. Thereafter, the release layer (hydroxypropylmethylcellulose phthalate layer) present on the insulating layer was dissolved and removed with a 1% by weight aqueous sodium carbonate solution. The metal film layer was uniformly transferred, and abnormalities such as swelling between the resin and the metal film layer, wrinkles of the metal film layer, and cracks in the metal film layer were not observed.

(Example 2)
A film with a metal film was prepared in the same manner as in Example 1 except that the polyethylene terephthalate film was changed to a polyethylene terephthalate film with a thickness of 50 μm manufactured by Toyobo Co., Ltd. and A4100 (Ra = 12 nm on a smooth surface). The metal film layer was transferred. The coating of hydroxypropylmethylcellulose phthalate was performed on a smooth surface of A4100 (Ra = 12 nm). In the manufacturing process of the film with a metal film, no crack occurred in the metal film. Further, the metal film layer was uniformly transferred, and no abnormalities such as swelling between the resin and the metal film layer, wrinkles in the metal film layer, and cracks in the metal film layer were observed.

(Example 3)
In Example 1, the polyethylene terephthalate film was made into a polyethylene naphthalate film having a thickness of 38 μm manufactured by Teijin DuPont Films Co., Ltd., Q83 (Ra = 32 nm on a smooth surface), and the hydroxypropyl methylcellulose phthalate layer had a layer thickness of about 0.5 μm, A film with a metal film was prepared in the same manner as in Example 1 except that the thickness of the metal film layer was about 2500 nm, and the metal film layer was transferred. In the manufacturing process of the film with a metal film, no crack occurred in the metal film layer. Further, the metal film layer was uniformly transferred, and no abnormalities such as swelling between the resin and the metal film layer, wrinkles in the metal film layer, and cracks in the metal film layer were observed.

(Example 4)
A film with a metal film was prepared in the same manner as in Example 1 except that the thickness of the hydroxypropylmethylcellulose phthalate layer was about 2 μm in Example 1, and the metal film layer was transferred. In the manufacturing process of the film with a metal film, no crack occurred in the metal film layer. Further, the metal film layer was uniformly transferred, and no abnormalities such as swelling between the resin and the metal film, wrinkles of the metal film layer, and cracks in the metal film layer were observed.

(Example 5)
In Example 3, a film with a metal film was produced in the same manner as in Example 1 except that the thickness of the hydroxypropylmethylcellulose phthalate layer was about 2 μm, and the metal film layer was transferred. In the manufacturing process of the film with a metal film, no crack occurred in the metal film layer. Further, the metal film layer was uniformly transferred, and no abnormalities such as swelling between the resin and the metal film layer, wrinkles in the metal film layer, and cracks in the metal film layer were observed.

(Example 6)
A film with a metal film was prepared in the same manner as in Example 1 except that the thickness of the hydroxypropylmethylcellulose phthalate layer was about 4 μm in Example 1, and the metal film layer was transferred. In the manufacturing process of the film with a metal film, no crack occurred in the metal film layer. Further, the metal film layer was uniformly transferred, and no abnormalities such as swelling between the resin and the metal film layer, wrinkles in the metal film layer, and cracks in the metal film layer were observed.

(Example 7)
The film with metal film produced in Example 1 was bonded at 90 ° C. so that the curable resin composition layer of the adhesive film produced in Example 1 and the metal film layer were in contact with each other, and wound to produce an adhesive film with metal film. did.

<Curable resin composition layer formation on a substrate by an adhesive film with a metal film>
The copper layer of the glass epoxy substrate on which a circuit is formed with an 18 μm thick copper layer is treated with CZ8100 (a surface treatment agent containing an azole copper complex and an organic acid, manufactured by MEC Co., Ltd.) for roughening. did. Next, the support on the adhesive film side of the produced adhesive film with a metal film is peeled off, and adhesion with a metal film is performed using a batch type vacuum pressure laminator MVLP-500 (trade name, manufactured by Meiki Seisakusho Co., Ltd.). The film was laminated on both sides of the substrate. Lamination was performed by reducing the pressure for 30 seconds to a pressure of 13 hPa or less. Thereafter, the curable resin composition layer was cured at 150 ° C. for 30 minutes and further at 180 ° C. for 30 minutes to form an insulating layer (cured product layer). The PET film which is the support layer on the side of the adhesive film with a metal film was peeled from the insulating layer. The peelability was good and it could be easily peeled by hand. Thereafter, the hydroxypropylmethylcellulose phthalate layer was immersed in a 1% by weight aqueous sodium carbonate solution at room temperature for 1 minute (with stirring), and dissolved and removed. The metal film layer was uniformly transferred, and abnormalities such as swelling between the resin and the metal film layer, wrinkles in the metal film layer, and cracks in the metal film layer were not observed.

(Example 8)
<Preparation of prepreg>
The resin varnish produced in Example 1 was impregnated with a glass fiber having a thickness of 50 μm and dried at 135 ° C. for 4 minutes to produce a prepreg having a resin varnish content of 52% by weight.

<Production of metal film-clad laminate>
In the film with a metal film produced in Example 1, the two prepregs produced above were arranged vertically so that the prepreg and the metal film layer were in contact with each other, under a pressure of 10 kgf / cm ² at 130 ° C. for 30 minutes, and then 30 kgf A metal film-clad laminate was produced by vacuum pressing at 190 ° C. for 90 minutes under a pressure of / cm ² . The PET film, which is the support layer on the metal film-attached film side, was peeled from the insulating layer. The peelability was good and it could be easily peeled by hand. Thereafter, the hydroxypropylmethylcellulose phthalate layer was immersed in a 1% by weight aqueous sodium carbonate solution at room temperature for 1 minute (with stirring), and dissolved and removed. The metal film layer was uniformly transferred, and abnormalities such as swelling between the resin and the metal film layer, wrinkles in the metal film layer, and cracks in the metal film layer were not observed.

(Comparative Example 1)
A film with a metal film was produced in the same manner as in Example 1, except that the polyethylene terephthalate film was changed to a polyethylene terephthalate film having a thickness of 38 μm and R56 (Ra = 67 nm) manufactured by Toray Industries, Inc. However, innumerable cracks occurred in the metal film layer.

(Comparative Example 2)
In Example 1, the polyethylene terephthalate film is a 38 μm thick polyethylene terephthalate film manufactured by Toray Industries, Inc., R56 (Ra = 67 nm), and the layer thickness of the metal film layer (copper film layer) is changed from about 500 nm to about 2500 nm. A film with a metal film was produced in the same manner as in Example 1 except that. However, innumerable cracks occurred in the metal film layer.

(Comparative Example 3)
In Example 1, the polyethylene terephthalate film was changed to a polyethylene terephthalate film having a thickness of 38 μm manufactured by Toray Industries, Inc., R56 (Ra = 67 nm), and the thickness of the hydroxypropylmethylcellulose phthalate layer was changed from about 0.5 μm to about 7 μm. Except for the above, a film with a metal film was prepared in the same manner as in Example 1, and the metal film was transferred. In the manufacturing process of the film with a metal film, no crack was generated in the metal film layer, but innumerable cracks were generated in the transferred metal film layer.

(Comparative Example 4)
In Example 1, the polyethylene terephthalate film is a 38 μm thick polyethylene terephthalate film manufactured by Toray Industries, Inc., R56 (Ra = 67 nm), and the thickness of the hydroxypropylmethylcellulose phthalate layer is about 0.5 μm to about 7 μm. A film with a metal film was produced in the same manner as in Example 1 except that the layer thickness was changed from about 500 nm to about 2500 nm. In the manufacturing process of the film with a metal film, no crack was generated in the metal film layer, but innumerable cracks were generated in the transferred metal film layer.

  FIG. 2 shows a photograph of an example of the surface of the metal film layer where cracks occurred in the comparative example.

<Surface roughness measurement>
The arithmetic average roughness (Ra value) was measured by using a non-contact type surface roughness meter (WYKO NT3300 manufactured by Becoins Instruments Co., Ltd.) with a VSI contact mode and a 50 × lens with a measurement range of 121 μm × 92 μm.

<Measurement of metal film layer thickness>
The film thickness of the metal film layer of the produced film with a metal film was measured with a fluorescent X-ray film thickness measuring device “SFT 9455” manufactured by SII Nanotechnology, and the value was read.

<Measurement of layer thickness of release layer>
The thickness of the release layer is determined by weighing the film before and after forming the release layer with an electronic balance, and obtaining the difference between them. Asked. Then, the layer thickness was calculated by setting the specific gravity of the release layer to 0.9 g / cm ³ .

<Crack evaluation>
The crack means a crack generated in the metal film layer, and the evaluation of the crack was observed using a microscope (Keyence Corporation, ultra-deep microscope “VK-8510”). The state of cracks when observing the surface of the metal film layer at a magnification of 100 is shown. The case where a crack was seen was set as “Yes”, and the case where no crack was found was set as “None”.

  This application is based on patent application No. 2008-222729 filed in Japan, the contents of which are incorporated in full herein.

Claims (19)

A release layer is formed on the surface of the support layer having an arithmetic average roughness (Ra) of 50 nm or less, and a metal film layer is formed on the release layer ,
At least the surface of the release layer that adheres to the metal film layer is formed of one or more water-soluble polymers selected from a water-soluble cellulose resin, a water-soluble polyester resin, and a water-soluble acrylic resin. the film.   The film with a metal film according to claim 1, wherein the release layer has a thickness of 0.1 to 5 μm.   The film with a metal film according to claim 1 or 2, wherein the metal film layer has a thickness of 50 nm to 5000 nm.   The film with a metal film according to any one of claims 1 to 3, wherein the metal film layer is formed by one or more methods selected from an evaporation method, a sputtering method, and an ion plating method. The film with a metal film according to any one of claims 1 to 4 , wherein the support layer is a plastic film. The film with a metal film according to any one of claims 1 to 4 , wherein the support layer is a polyethylene terephthalate film. The film with a metal film according to any one of claims 1 to 6 , wherein the thickness of the support layer is from 10 µm to 70 µm. A film with a metal film according to any one of claims 1 to 7 is laminated on an adherend comprising at least a surface layer of a curable resin composition so that the metal film layer is in contact with the surface of the adherend. And a method for transferring the metal film layer, including a step of curing the curable resin composition and a step of peeling the support layer. Kim further comprising a Shokumaku step of dissolving and removing an aqueous solution of the release layer present on the layer, transferring method of the metal film layer of claim 8. The film with a metal film according to any one of claims 1 to 7 , wherein the metal film layer is in contact with the surface of the curable resin composition layer on the curable resin composition layer formed on the inner layer circuit board. A method for manufacturing a circuit board, comprising: a step of stacking layers and curing a curable resin composition layer; and a step of peeling a support layer. Kim further comprising the step of dissolving and removing the release layer with an aqueous solution Shokumaku present on the layer, the manufacturing method of the circuit board according to claim 10, wherein. The method according to claim 10 or 11 , further comprising a step of forming a conductor layer by plating on the metal film layer. The method according to any one of claims 10 to 12 , wherein the curable resin composition layer is made of a prepreg in which a sheet-like substrate made of fibers is impregnated with the curable resin composition. The film with a metal film according to any one of claims 1 to 7 , wherein the metal film layer is in contact with the surface of the prepreg on one side or both sides of a single prepreg or a multilayer prepreg obtained by stacking a plurality of prepregs. A method for producing a metal-clad laminate, including a step of heating and pressurizing the substrate and a step of peeling the support layer. Further comprising the step of dissolving and removing the release layer present on the gold Shokumaku layer with an aqueous solution, method for producing a metal-clad laminate of claim 14 wherein. On the metal film layer of the film according to any one of claims 1 to 7, are formed further curable resin composition layer, adhesive film with a metal film. A step of laminating the adhesive film with a metal film according to claim 16 on an inner circuit board so that the curable resin composition layer is in contact with the inner circuit board, a step of curing the curable resin composition layer, and a support layer The manufacturing method of a circuit board including the process of peeling. Kim further comprising a Shokumaku step of dissolving and removing an aqueous solution of the release layer present on the layer, the manufacturing method of the circuit board according to claim 17. The method according to claim 17 or 18 , further comprising a step of forming a conductor layer on the metal film layer by plating.