JP2017202606A - Polyimide film with resin, polyimide film including resin layer, laminate for printed wiring board, and method for manufacturing printed wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyimide film with resin that has a surface roughness of a resin layer reduced, and has high adhesiveness on a metal thin film even with the reduced surface roughness of the resin layer, and also provide a polyimide film including a resin layer obtained by thermally hardening the polyimide film with resin, a laminate for printed wiring boards, and a method for manufacturing a printed wiring board.SOLUTION: A polyimide film with resin includes a resin composition containing (A) epoxy resin and (B) an active ester group-containing compound, and a polyimide film.SELECTED DRAWING: None

Description

  The present invention relates to a polyimide film with a resin, a polyimide film provided with a resin layer, a laminate for a printed wiring board, and a method for producing a printed wiring board.

  As electronic devices become smaller, lighter, and more functional, LSIs and chip components are becoming more highly integrated, and their forms are rapidly changing to higher pins and smaller sizes. . For this reason, in order to improve the mounting density of electronic components, development of printed wiring boards that can cope with fine wiring has been underway. As such a printed wiring board, there is a build-up type printed wiring board that uses an insulating resin not containing a glass cloth instead of a prepreg, and forms a wiring layer while connecting only necessary portions with via holes. It is becoming mainstream as a method suitable for miniaturization and miniaturization.

In this build-up type printed wiring board, first, a resin layer (insulating resin layer) is formed on a substrate having a circuit. And after hardening this resin layer, in order to ensure the adhesive strength with a wiring conductor, the resin layer surface is immersed in an oxidizing treatment liquid, and a roughening process is performed. Next, electroless plating is performed by pre-plating treatment. Further, after forming a resist pattern on the electroless plating layer and thickening by electroplating, the resist pattern is peeled off, and the electroless plating layer is removed to obtain a printed wiring board.
However, with the miniaturization of the wiring, the unevenness on the surface of the resin layer formed by roughening the surface of the resin layer causes a decrease in the yield of wiring formation. This is because the electroless metal plating layer bites into the irregularities on the surface of the resin layer, making it difficult to remove and causing a wiring short, and the formation accuracy of the resist pattern is reduced due to the irregularities on the surface of the resin layer. Etc.

Therefore, reducing the unevenness on the surface of the resin layer is important for realizing fine wiring. However, if the unevenness is reduced, the adhesive strength between the resin layer and the electroless metal plating layer is lowered, so the adhesive strength is improved. It is necessary to let
In response to these requirements, for example, a resin layer using a polyphenylene ether resin is irradiated with ultraviolet rays in the presence of oxygen to provide a conductor layer, and then heat-treated before forming a circuit in the conductor layer, or a conductor A method of performing a heat treatment after forming a circuit in a layer has been proposed (for example, see Patent Document 1).

JP 2004-214597 A

In patent document 1, the unevenness | corrugation of the surface of a resin layer is suppressed, and it makes it the subject to make the adhesiveness of a resin layer and a conductor layer favorable. However, in Patent Document 1, a method of curing with a support attached is used to improve yield, but according to the study by the present inventors, a resin using a support such as polyethylene terephthalate (PET) is attached. It was found that when the support was heated, the oligomer component precipitated from the support and was present in the vicinity of the interface between the resin layer and the support, resulting in increased unevenness on the surface of the resin layer (see FIG. 1).
In view of such circumstances, the present invention suppresses the surface roughness of the resin layer to provide a polyimide film with a resin having high adhesion to a metal thin film even when the surface roughness of the resin layer is small. Another object of the present invention is to provide a polyimide film provided with a resin layer obtained by thermosetting the polyimide film with resin, a laminate for a printed wiring board, and a method for producing a printed wiring board.

  As a result of earnest research to solve the above problems, the present inventors have solved the above problems by combining a polyimide film with a resin composition containing an epoxy resin and an active ester group-containing compound. The present invention has been found and the present invention has been completed. The present invention has been completed based on such knowledge.

The present invention relates to the following [1] to [9].
[1] A resin-coated polyimide film comprising: (A) an epoxy resin and (B) a resin composition containing an active ester group-containing compound; and a polyimide film.
[2] The polyimide film with a resin according to the above [1], wherein the (A) epoxy resin has a structural unit derived from an alkylene glycol having 3 or more carbon atoms.
[3] The resin-coated polyimide film according to the above [1] or [2], wherein the resin composition further contains an inorganic filler.
[4] The resin according to any one of the above [1] to [3], wherein the (B) active ester group-containing compound is an aromatic ester compound having a structural unit represented by the following general formula (V): With polyimide film.

[5] A polyimide film provided with a resin layer obtained by heat-curing the resin-coated polyimide film according to any one of [1] to [4], wherein the polyimide film side surface of the resin layer is The polyimide film provided with the resin layer whose surface roughness is 0.1 micrometer or less.
[6] A laminate for a printed wiring board, which is formed by laminating a substrate material and a polyimide film with a resin according to any one of [1] to [4].
[7] A method for producing a printed wiring board, comprising the following steps.
(1) A step of laminating a substrate material and the polyimide film with resin according to any one of the above [1] to [4] to form a laminate for a printed wiring board.
(2) A step of heating the printed wiring board laminate obtained in step (1).
(3) A step having the following step (3-i) or the following steps (3-i) and (3-ii).
(3-i) The process of removing a polyimide film from the laminated body for printed wiring boards obtained at the process (1).
(3-ii) A step of irradiating the laminate for a printed wiring board obtained in the step (3-i) with ultraviolet rays.
(4) A step of forming a circuit pattern on the printed wiring board laminate obtained in step (3).
[8] The method for producing a printed wiring board according to [7], wherein the heating temperature in the step (2) is 160 to 300 ° C.
[9] The method for producing a printed wiring board according to the above [7] or [8], wherein an integrated light amount of ultraviolet rays in the step (3-ii) is 2,000 to 5,000 mJ / cm ² .

  According to the present invention, it is possible to provide a polyimide film with a resin that suppresses the surface roughness of the resin layer to be small and has high adhesion to the metal thin film even in a state where the surface roughness of the resin layer is small. Furthermore, the laminated body for printed wiring boards can be provided with the polyimide film provided with the resin layer which heat-processes this polyimide film with resin, In addition, the manufacturing method of a printed wiring board can also be provided.

It is a scanning electron micrograph figure of the film surface when a PET film is heated at 180 degreeC for 60 minutes.

[Polyimide film with resin]
The polyimide film with resin of the present invention comprises (A) an epoxy resin and (B) a resin composition containing an active ester group-containing compound, and a polyimide film. Hereinafter, the resin composition and the polyimide film will be described in detail in order.

(Resin composition)
The resin composition comprises (A) an epoxy resin (hereinafter sometimes referred to as “(A) component”) and (B) an active ester group-containing compound (hereinafter sometimes referred to as “(B) component”). Containing. Hereinafter, each component which a resin composition contains is demonstrated in order.
((A) component: epoxy resin)
The epoxy resin is an epoxy resin having two or more epoxy groups in one molecule. From the viewpoint of improving heat resistance, an aromatic epoxy resin is preferable.
The epoxy equivalent of the epoxy resin is preferably 50 to 3,000 g / eq, more preferably 80 to 2,000 g / eq, and still more preferably 100 to 1,000 g / eq. Here, the epoxy equivalent is the mass (g / eq) of resin per equivalent of epoxy groups, and can be measured according to the method defined in JIS K 7236 (2001). Specifically, using an automatic titration apparatus “GT-200 type” (manufactured by Mitsubishi Chemical Analytech Co., Ltd.), 2 g of epoxy resin was weighed into a 200 ml beaker, 90 ml of methyl ethyl ketone was dropped, and after dissolving in an ultrasonic cleaner, It is determined by adding 10 ml of glacial acetic acid and 1.5 g of cetyltrimethylammonium bromide and titrating with a 0.1 mol / L perchloric acid / acetic acid solution.

Examples of the epoxy resin include a cresol novolak type epoxy resin, a phenol novolak type epoxy resin, a naphthol novolak type epoxy resin, an aralkyl novolak type epoxy resin, a biphenyl novolak type epoxy resin, a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, and a bisphenol. S type epoxy resin, bisphenol T type epoxy resin, bisphenol Z type epoxy resin, tetrabromobisphenol A type epoxy resin, biphenyl type epoxy resin, tetramethylbiphenyl type epoxy resin, triphenyl type epoxy resin, tetraphenyl type epoxy resin, naphthol Aralkyl-type epoxy resin, Naphthalene all-aralkyl-type epoxy resin, Naphthol aralkyl-type epoxy resin, Fluorene-type epoxy resin Carboxymethyl resins, epoxy resins having a dicyclopentadiene skeleton, epoxy resins having an ethylenically unsaturated group in the backbone, the alicyclic type epoxy resins. An epoxy resin may be used individually by 1 type, and may use 2 or more types together from a viewpoint of insulation reliability and heat resistance.
Examples of commercially available epoxy resins include “jER828EL” and “YL980” (manufactured by Mitsubishi Chemical Corporation), which are bisphenol A type epoxy resins, and “jER806H” and “YL983U”, which are bisphenol F type epoxy resins. (Above, manufactured by Mitsubishi Chemical Corporation).

Here, the epoxy resin is not particularly limited, but from the viewpoint of imparting flexibility, it has two or more epoxy groups in one molecule and is derived from an alkylene glycol having 3 or more carbon atoms. Epoxy resins having structural units are preferred. The structural unit derived from the alkylene glycol having 3 or more carbon atoms is preferably included in the main chain of the epoxy resin. Further, from the viewpoint of further improving flexibility, it is preferable that two or more structural units derived from an alkylene glycol having 3 or more carbon atoms are continuously repeated.
Note that “having a structural unit derived from an alkylene glycol having 3 or more carbon atoms” may be obtained by using an alkylene glycol having 3 or more carbon atoms as a monomer, or an alkylene having 3 or more carbon atoms. It may be obtained using a compound having a glycol skeleton.

The alkylene glycol having 3 or more carbon atoms is preferably an alkylene glycol having 4 or more carbon atoms. The upper limit of the carbon number is not limited, but is preferably 15 or less, more preferably 10 or less, and still more preferably 8 or less. As the epoxy resin, for example, a bisphenol A type epoxy resin having a structural unit derived from alkylene glycol having 4 to 8 carbon atoms in the main chain is preferable, and a bisphenol A type epoxy resin having a structural unit derived from hexanediol in the main chain. Is more preferable.
Specific examples of the epoxy resin having a structural unit derived from an alkylene glycol having 3 or more carbon atoms in the main chain include, for example, a vinyl ether compound represented by the following general formula (I) and a bifunctional compound represented by the following general formula (II). The epoxy resin obtained by making it react with a phenol compound is mentioned. More specifically, after reacting a vinyl ether compound represented by the following general formula (I) with a bifunctional phenol compound represented by the following general formula (II), the terminal is epoxidized with an epihalohydrin such as epichlorohydrin. Can be manufactured. The epoxy resin has a structure derived from an alkylene diol represented by HO [—R ¹ —O] n—H (R ¹ and n are the same as those in the general formula (I)), and It can also be said that it has a structure derived from a bifunctional phenol compound represented by the general formula (II).

In the general formula (I), ^{R 1} is an aliphatic hydrocarbon group having 1 to 10 carbon atoms. R ² represents an aliphatic hydrocarbon group having 1 to 10 carbon atoms, preferably an aliphatic hydrocarbon group having 1 to 5 carbon atoms, more preferably an aliphatic hydrocarbon group having 1 to 3 carbon atoms. N represents an integer of 1 to 15, preferably an integer of 1 to 10, more preferably an integer of 1 to 5, still more preferably an integer of 1 to 3, and particularly preferably 1.
Examples of the aliphatic hydrocarbon group having 1 to 10 carbon atoms represented by R ¹ include a methylene group, a 1,2-dimethylene group, a 1,2-trimethylene group, a 1,3-trimethylene group, and a 1,4-tetramethylene group. And an alkylene group having 1 to 10 carbon atoms such as 1,5-pentamethylene group, 1,6-hexamethylene group and 1,9-nonamethylene group. The alkylene group having 1 to 10 carbon atoms is preferably an alkylene group having 2 to 10 carbon atoms, more preferably an alkylene group having 2 to 7 carbon atoms, and further preferably a 1,6-hexamethylene group.
Examples of the aliphatic hydrocarbon group having 1 to 10 carbon atoms represented by R ² include a methylene group, a 1,2-dimethylene group, a 1,3-trimethylene group, a 1,4-tetramethylene group, and 1,5-penta. An alkylene group having 1 to 10 carbon atoms such as a methylene group; an alkylidene group having 2 to 10 carbon atoms such as an ethylidene group, a propylidene group, an isopropylidene group, a butylidene group, an isobutylidene group, a pentylidene group, and an isopentylidene group. . The alkylene group having 1 to 10 carbon atoms is preferably an alkylene group having 1 to 5 carbon atoms, more preferably an alkylene group having 1 to 3 carbon atoms. The alkylidene group having 2 to 10 carbon atoms is preferably an alkylidene group having 2 to 5 carbon atoms, more preferably an alkylidene group having 2 to 3 carbon atoms, and further preferably an isopropylidene group. R ² is preferably an alkylidene group having 2 to 10 carbon atoms, more preferably as described above.
R ² is preferably bonded at the 4-position of phenol.
As a commercial item of the epoxy resin which has a structural unit shown by general formula (I), "Epiclon EXA-4816" (the DIC Corporation make, epoxy resin which has bisphenol A and a long-chain aliphatic skeleton) etc. are mentioned, for example. .

The epoxy resin may be an aralkyl novolac type epoxy resin having a biphenyl structure. The aralkyl novolak type epoxy resin having a biphenyl structure refers to an aralkyl novolak type epoxy resin containing an aromatic ring of a biphenyl derivative in the molecule. For example, an epoxy resin having a structural unit represented by the following formula (III) Can be mentioned.

Commercially available epoxy resins having the structural unit represented by the formula (III) include “NC-3000” (epoxy equivalent = 275 g / eq), “NC-3000H” (epoxy equivalent = 290 g / eq, the following formula ( See IV)) [Nippon Kayaku Co., Ltd.].

(In formula (IV), p represents 1 to 5. p is preferably 1.2 to 5, and more preferably 1.4 to 3.)

  Although there is no restriction | limiting in particular in content of (A) component in a resin composition, From a viewpoint of improving adhesiveness, 30 mass% or more is preferable on the basis of the total mass (total solid content) of a resin composition, and 40 mass % Or more is more preferable, and 50 mass% or more is more preferable. Moreover, from a viewpoint of improving laser workability, 85 mass% or less is preferable on the basis of the total mass (total solid content) of a resin composition, 80 mass% or less is more preferable, 75 mass% or less is more preferable.

((B) component: active ester group-containing compound)
The active ester group-containing compound can function as a curing agent for the component (A). Here, the “active ester group” means an ester group that can react with an epoxy resin. In addition, this ester group containing compound decomposes | disassembles by the ultraviolet irradiation mentioned later, As a result, it contributes to the improvement of adhesiveness with a metal thin film.
Examples of the active ester group-containing compound include ester compounds obtained by reacting aliphatic carboxylic acids or aromatic carboxylic acids with aliphatic hydroxy compounds or aromatic hydroxy compounds.
An aliphatic ester compound obtained from an aliphatic carboxylic acid and an aliphatic hydroxy compound tends to have high solubility in an organic solvent and compatibility with an epoxy resin by including an aliphatic chain. In addition, an aromatic ester compound obtained from an aromatic carboxylic acid and an aromatic hydroxy compound has an aromatic ring and tends to have high heat resistance. Among these, the latter aromatic ester compound is preferable.
Examples of the aromatic carboxylic acid include aromatic carboxylic acids in which 2 to 4 hydrogen atoms of an aromatic compound such as benzene, naphthalene, biphenyl, diphenylpropane, diphenylmethane, diphenyl ether, and diphenylsulfonic acid are substituted with a carboxyl group. preferable. Examples of the aromatic hydroxy compound include a monovalent phenol in which one of the hydrogen atoms of the aromatic compound is substituted with a hydroxyl group, or a polyhydric phenol in which 2 to 4 hydrogen atoms of the aromatic compound are substituted with a hydroxyl group. preferable. The active ester group-containing compound is preferably an aromatic ester obtained by a condensation reaction of an aromatic carboxylic acid and a phenolic hydroxyl group using a mixture of the aromatic carboxylic acid and the aromatic hydroxy compound as a raw material. Is done.
From the viewpoint of reducing warpage, the active ester group-containing compound is preferably an aromatic ester compound, and more preferably an ester group having an aromatic ring which may be substituted at both ends. For example, an aromatic ester compound having a structural unit represented by the following general formula (V) is preferable.

The active ester group-containing compound is also available as a commercial product. As a commercial item, EXB-9451, EXB-9460, EXB-9460S, EXB-9480, EXB-9420 (all are the brand names made by DIC Corporation), BPN80 (the Mitsui Chemicals brand name, brand names) etc., for example. Is mentioned.
An active ester group containing compound may be used individually by 1 type, and may use 2 or more types together.

  The content of the active ester group-containing compound is preferably such that the ester group of the active ester group-containing compound is 0.3 to 1.5 equivalents relative to 1 equivalent of the epoxy group of the epoxy resin. More preferred is an amount of 3 to 1.25 equivalents, and even more preferred is an amount of 0.5 to 0.9 equivalents. Within this range, the heat resistance and glass transition temperature tend to be better.

(Other ingredients)
The resin composition may further contain other components not corresponding to the components (A) and (B). Examples of other components include a curing agent [other than the component (B)], a curing accelerator, an inorganic filler, an organic filler, a leveling agent, an antioxidant, a flame retardant, a thixotropic agent, a thickener, Examples include thixotropic agents, surfactants, coupling agents, and the like, and it is preferable to contain at least one selected from these.

(Curing agent)
Examples of the curing agent include epoxy resin curing agents such as phenol-based curing agents, cyanate ester-based curing agents, and acid anhydride-based curing agents. A hardening | curing agent may be used individually by 1 type, and may use 2 or more types together.

Although it does not restrict | limit especially as a phenol type hardening | curing agent, For example, a cresol novolak type hardening | curing agent, a biphenyl type hardening | curing agent, a phenol novolak type hardening | curing agent, a naphthylene ether type hardening | curing agent, a triazine skeleton containing phenol type hardening | curing agent etc. are mentioned preferably. .
Examples of commercially available phenolic curing agents include cresol novolac type curing agents such as KA-1160, KA-1163, and KA-1165 (all manufactured by DIC Corporation, trade names); MEH-7700, MEH-7810, Biphenyl type curing agents such as MEH-7851 (both made by Meiwa Kasei Co., Ltd., trade name); phenol novolac type curing agents such as TD2090 (made by DIC, trade name); EXB-6000 (made by DIC Corporation, product) Naphthylene ether type curing agents such as LA3018, LA7052, LA7054, and LA1356 (all manufactured by DIC Corporation, trade names) and the like.

The cyanate ester curing agent is not particularly limited, and examples thereof 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-dimethylphenyl) methane, 1,3-bis (4-cyanatephenyl-1- (methylethylidene)) benzene, bis (4-cyanatephenyl) thioether, bis (4-cyanatephenyl) ether and the like. It is done.
The acid anhydride curing agent is not particularly limited. For example, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylnadic acid anhydride, Hydrogenated methyl nadic anhydride, trialkyltetrahydrophthalic anhydride, dodecenyl succinic anhydride, 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic acid Anhydride, trimellitic anhydride, pyromellitic anhydride, etc. are mentioned.

(Curing accelerator)
As a hardening accelerator, the general hardening accelerator used for hardening of an epoxy resin can be used. Examples of the curing accelerator include imidazole compounds and derivatives thereof; phosphorus compounds; tertiary amine compounds; quaternary ammonium compounds and the like. From the viewpoint of promoting the curing reaction, imidazole compounds and derivatives thereof are preferred.
Specific examples of the imidazole compound and derivatives thereof include, for example, 2-methylimidazole, 2-ethylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-phenylimidazole, 1,2-dimethylimidazole, 2-ethyl. -1-methylimidazole, 1,2-diethylimidazole, 1-ethyl-2-methylimidazole, 2-ethyl-4-methylimidazole, 4-ethyl-2-methylimidazole, 2-phenyl-4-methylimidazole, 1 -Benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 2- Phenyl- , 5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo [1,2-a] benzimidazole, 2,4-diamino-6- [2 '-Methylimidazolyl- (1')] ethyl-s-triazine, 2,4-diamino-6- [2'-undecylimidazolyl- (1 ')] ethyl-s-triazine, 2,4-diamino-6 An imidazole compound such as [2′-ethyl-4′-methylimidazolyl- (1 ′)] ethyl-s-triazine; the imidazole compound such as 1-cyanoethyl-2-phenylimidazolium trimellitate and trimellitic acid; A salt of the imidazole compound and isocyanuric acid; a salt of the imidazole compound and hydrobromic acid, and the like. An imidazole compound may be used individually by 1 type, and may use 2 or more types together.

(Inorganic filler)
The inorganic filler can reduce the coefficient of thermal expansion and improve the coating strength.
Examples of inorganic fillers include silica, alumina, barium sulfate, talc, mica, kaolin, boehmite, beryllia, barium titanate, potassium titanate, strontium titanate, calcium titanate, aluminum carbonate, magnesium hydroxide, hydroxide Clays such as aluminum, aluminum borate, aluminum silicate, calcium carbonate, calcium silicate, magnesium silicate, zinc borate, zinc stannate, zinc oxide, titanium oxide, silicon carbide, silicon nitride, boron nitride, calcined clay, Examples thereof include short glass fibers, glass powder, and hollow glass beads, and at least one selected from the group consisting of these is preferably used. Preferred examples of the glass include E glass, T glass, and D glass. Among these, silica and alumina are preferable and silica is more preferable from the viewpoints of reduction of thermal expansion coefficient, relative dielectric constant, and dielectric loss tangent.
Examples of the silica include precipitated silica produced by a wet method and having a high water content, and dry method silica produced by a dry method and containing almost no bound water or the like. Examples of the dry silica include crushed silica, fumed silica, and fused silica (fused spherical silica) depending on the production method. Among these, fumed silica is preferable.
The inorganic filler may be surface-treated with a surface treatment agent such as a silane coupling agent in order to improve moisture resistance, or may be hydrophobized to improve dispersibility.

The inorganic filler can be appropriately selected depending on the purpose. From the viewpoint of facilitating the formation of fine wiring on the resin layer, the specific surface area of the inorganic filler is preferably 20 m ² / g or more, more preferably 30 to 250 m ² / g, still more preferably 50 to ²⁰⁰ m ² / g, Most preferably, it is 60-160 m < ² > / g. The specific surface area of the inorganic filler can be determined by a measurement method usually performed by those skilled in the art, and can be measured, for example, by the BET method. The BET method is a method in which molecules having a known adsorption occupation area are adsorbed on the surface of powder particles at the temperature of liquid nitrogen, and the specific surface area of the sample is obtained from the amount. In the specific surface area analysis, the BET method using an inert gas such as nitrogen is most often used.

From the viewpoint of reducing the surface shape after the roughening treatment in the plating process, for example, the average primary particle diameter of the inorganic filler is preferably 100 nm or less, more preferably 1 to 80 nm, still more preferably 1 to 50 nm, Preferably it is 5-30 nm. Here, the “average primary particle diameter” refers to the average diameter of aggregated particles, that is, the average particle diameter of a single substance that is not aggregated, not the secondary particle diameter. The primary average particle diameter can be determined by measuring with a laser diffraction particle size distribution meter. The average primary particle size is the particle size at a point corresponding to a volume of 50% when a cumulative frequency distribution curve based on the particle size is obtained with the total particle volume as 100%.
Commercially available inorganic fillers having an average primary particle diameter of 100 nm or less include, for example, AEROSIL R972 (specific surface area = 110 ± 20 m ² / g, average primary particle diameter≈16 nm, catalog value), AEROSIL R202 (specific surface area = 100 ± 20 m ² / g, average primary particle size ≈ 14 nm, catalog value) [above, Nippon Aerosil Co., Ltd., trade name]; PL-1 (specific surface area = 181 m ² / g, average primary particle size = 15 nm, catalog value) ) And PL-7 (specific surface area = 36 m ² / g, average primary particle size = 75 nm, catalog value) [above, manufactured by Fuso Chemical Industries, Ltd., trade name]; AL-A06 (specific surface area = 55 m ² / g, catalog value) [CIK Nanotech Co., Ltd., trade name; "SO-C1" (spherical silica, specific surface area = ^17m 2 / g, catalog value) Ltd. De Matex made, there is a trade name], and the like.

  When the resin layer contains an inorganic filler, the content thereof is preferably 1 to 35% by mass in all components used for forming the resin layer (excluding the organic solvent). -30 mass% is more preferable, and 1-15 mass% is further more preferable. If the content of the inorganic filler is 1% by mass or more, the coefficient of thermal expansion tends to be low. On the other hand, if the content is 35% by mass or less, the resin flow becomes sufficient when the resin layer is formed in the inner layer circuit. There is a tendency that unfilled portions are less likely to occur.

(Organic solvent)
From the viewpoint of facilitating handling, the resin composition may further contain an organic solvent. In this specification, the resin composition containing an organic solvent may be referred to as a resin varnish.
Examples of the organic solvent include, but are not limited to, alcohol solvents such as methanol, ethanol, propanol, butanol, methyl cellosolve, butyl cellosolve, and propylene glycol monomethyl ether; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone. Ester solvents such as butyl acetate and propylene glycol monomethyl ether acetate; ether solvents such as tetrahydrofuran; aromatic solvents such as toluene, xylene and mesitylene; dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, etc. Nitrogen atom-containing solvents; sulfur atom-containing solvents such as dimethyl sulfoxide. Among these, from the viewpoint of solubility and appearance after coating, a ketone solvent is preferable, acetone, methyl ethyl ketone, and methyl isobutyl ketone are more preferable, and methyl ethyl ketone is more preferable.
An organic solvent may be used individually by 1 type, and may use 2 or more types together.

  The content of the organic solvent is appropriately adjusted according to the equipment for forming the resin layer. For example, the solid content of the resin composition is preferably 20 to 70% by mass, more preferably 40 to 70% by mass. Adjust the amount of organic solvent used.

(Method for preparing resin composition)
There is no restriction | limiting in particular in the preparation method of the said resin composition, A conventionally well-known preparation method is employable.
For example, (A) an epoxy resin, (B) an active ester group-containing compound, and other components as necessary are added to the solvent, and then mixed and stirred using various mixers to obtain a varnish. Can be prepared as Examples of the mixer include an ultrasonic dispersion method, a high-pressure collision dispersion method, a high-speed rotation dispersion method, a bead mill method, a high-speed shear dispersion method, and a rotation and revolution dispersion method.

  The resin composition obtained as described above is useful as a material for a resin layer for plating process, for example. For example, as described later, a printed wiring board can be obtained by arranging a resin layer made of a cured product of the resin composition on a substrate material and forming a conductor layer on the resin layer by plating. The resin layer obtained from the resin composition can be suitably used, for example, for producing a wiring board on which fine wiring is formed. Specifically, it can be suitably used to form a wiring having a line and space (L / S) of 10 μm / 10 μm or less.

[Polyimide film]
In the present invention, a polyimide film is used as the support in order to reduce the surface roughness of the resin layer. Since the polyimide film has high heat resistance as compared with other component films such as a polyethylene terephthalate (PET) film, for example, precipitation of components in the film can be suppressed, and increase in the surface roughness of the resin layer can be suppressed. .
As a polyimide film, what has moderate intensity | strength and does not cause a tear etc. when peeling a polyimide film is preferable. For example, from the viewpoint of film strength, an aromatic polyimide in which aromatic compounds are directly connected by an imide bond is preferable.
A commercially available product may be used as the polyimide film. Examples of commercially available products include Neoprim (polyimide film, Mitsubishi Gas Chemical Co., Ltd., trade name), Upilex R, Upilex S, Upilex SGA (above, Ube Industries, Ltd., trade name), Kapton H, Kapton V, Kapton E, Kapton EN, Kapton ENZT (above, product name manufactured by Toray DuPont Co., Ltd.), Apical AH, Apical NPI (above, product name manufactured by Kaneka Co., Ltd.), and the like.

Although the thickness of a polyimide film is suitably selected according to the objective, 10 micrometers-150 micrometers are preferable from a viewpoint of the followable | trackability and peelability of a film, for example, and 10 micrometers-50 micrometers are more preferable.
The surface roughness (Ra) of the polyimide film is, for example, preferably 0.2 μm or less, more preferably 0.1 μm or less from the viewpoint of improving the flatness of the molded body or laminated body after peeling. More preferably, it is 0.08 μm or less. Here, “surface roughness of the polyimide film” indicates the surface roughness of the surface on which the resin layer is formed.

  Since a polyimide film has the intensity | strength which does not heat-melt in a high temperature range, it is also possible to use it at 150-300 degreeC, for example. Moreover, it does not show clear glass transition temperature in the said range, Furthermore, it is preferable that a storage elastic modulus (10 Hz) exceeds 1 GPa.

  The polyimide film may be appropriately treated with a release agent from the viewpoint of facilitating peeling from the resin layer. Examples of the releasing agent include silicone resins, fluorine resins, polyolefin resins, alkyd resins, and the like. Further, if necessary, an easy lubricant, an antistatic agent and the like can be added to the release agent. Since static electricity frequently occurs in the hot pressing process, it is preferable to add an antistatic agent. Moreover, you may form an antistatic layer by apply | coating an antistatic agent to the surface in which the mold release layer is not formed.

The material for the release agent can be appropriately selected depending on the application. As an example, a silicone resin is preferable because it does not generate harmful gas at the price and incineration, and a silicone compound that can easily adjust the surface tension and is suitable for forming a thin film on the entire film is preferable.
Further, as the release agent, a thermosetting silicone resin in which the components of the release agent are transferred to the molded body or the laminated body during the hot press process and hardly adversely affect the peelability is preferable. Examples of the thermosetting silicone resin include a silicone-containing aminoalkyd resin.
The thickness of the release layer is preferably in the range of 0.01 to 10 μm, and more preferably in the range of 0.02 to 5 μm. When the thickness of this layer is in the range of 0.01 to 10 μm, a uniform layer is easily obtained, and the peelability is improved. Moreover, it can suppress that the component of a mold release agent transfers to an contact bonding layer after hot-plate press, and suppresses a bad influence on peelability. Furthermore, it is possible to suppress a decrease in heat resistance of the molded body or the laminated body due to the transfer of the release agent component to the molded body or the laminated body.
As a method for forming a release layer on a polyimide film, there is a method of applying to a film using a reverse roll coater, a gravure coater, a rod coater, an air doctor coater or other coating devices.

(Manufacturing method of polyimide film with resin)
The polyimide film with a resin of the present invention can be produced, for example, by applying the resin composition on a polyimide film and then drying it to make the resin composition into a B-stage. More specifically, after coating a resin composition containing an organic solvent (also referred to as a resin varnish) on a polyimide film, it can be produced, for example, by drying at 80 to 150 ° C. for 1 to 10 minutes.
Although there is no restriction | limiting in particular in the method of apply | coating a resin composition, For example, the method of using a die coater, a gravure coater, a comma coater, a reverse coater, an air doctor coater, a lip coater etc. is mentioned.
If the temperature of the drying treatment is 80 ° C. or more and the drying treatment time is 1 minute or more, it tends to be able to effectively suppress the generation of voids in the B-staged resin layer. In addition, if the temperature of the drying process is 150 ° C. or less and the time of the drying process is 10 minutes or less, a decrease in the resin flow amount due to excessive drying tends to be further suppressed.
In addition, the B-staged resin composition is in a state where the organic solvent in the resin varnish has been volatilized by drying, and is in an uncured state where the curing treatment described later is not performed.
The thickness of the layer of the resin composition after drying is preferably 1 to 60 μm, more preferably 1 to 20 μm, still more preferably 1 to 10 μm, and particularly preferably 2 to 6 μm. When the thickness is 0.5 μm or more, the adhesion to the metal thin film is likely to be improved, and the insulating property tends to be ensured. If the thickness is 60 μm or less, the manufacturing cost tends to be kept low.

[Polyimide film with resin layer]
The present invention is a polyimide film having a resin layer formed by thermosetting the polyimide film with resin, wherein the resin layer has a surface roughness of 0.1 μm or less on the polyimide film side surface. A polyimide film with a layer is also provided.
That is, the resin composition is cured and a resin layer is formed by thermosetting the polyimide film with resin. The resin layer exhibits high adhesion to a conductor layer (metal thin film) formed by electroless plating even when the surface roughness is small.
In addition, although there is no restriction | limiting in particular in thermosetting processing conditions, For example, Preferably it is 160-300 degreeC, More preferably, it is 160-230 degreeC, More preferably, it is 160-200 degreeC, Preferably it is made to heat for 15 to 180 minutes, and is hardened. . In particular, the surface roughness of the resin layer obtained by heating and curing at 180 ° C. for 60 minutes is preferably 0.1 μm or less.

[Laminated body for printed wiring board]
This invention also provides the laminated body for printed wiring boards formed by carrying out lamination molding of the board | substrate material and the said polyimide film with resin. Preferably, it is a laminate for a printed wiring board laminated so that the resin composition side of the polyimide film with resin and the substrate material face each other.
Examples of the substrate material include an insulating substrate having a circuit (insulating substrate with circuit), a base material (insulating base material) that is an insulator, and the like. The substrate material may be a laminate used for manufacturing a multilayer wiring board, such as a laminate in which an insulating base material is laminated on an insulating substrate with circuit.

The insulating substrate with a circuit is not particularly limited as long as it is an insulating substrate provided with a circuit on at least one main surface. In addition to an insulating substrate provided with a circuit only on one side, a double-sided copper-clad laminate is used. As obtained, circuits may be formed on both sides of the insulating substrate. As the insulating substrate with a circuit, a known laminated board [glass cloth-epoxy resin, paper-phenol resin, paper-epoxy resin, glass cloth and glass paper-epoxy resin, etc.] used in ordinary wiring boards is used. can do. Further, it may be a multilayer board in which three or more circuits are formed.
The circuit of the insulating substrate with circuit may be formed by any known method. For example, a subtractive method of etching and removing unnecessary portions of the copper foil in a copper clad laminate in which a copper foil and the insulating base material are bonded together, and a circuit is formed by electroless plating at a necessary portion of the insulating substrate. A known method for manufacturing a printed wiring board, such as an additive method, can be employed.

  Further, a surface treatment for improving adhesion may be performed on the surface on which the circuit is formed. The surface treatment method is not particularly limited. For example, copper oxide needle crystals are formed on the circuit surface with an alkaline aqueous solution such as sodium hypochlorite, and the formed copper oxide needle crystals are immersed in a dimethylamine borane aqueous solution. A known method such as reduction can be employed.

  The insulating substrate is not particularly limited as long as it is an insulator, and a known insulating substrate for a wiring board such as a prepreg or a resin film can be used. Examples of commercially available prepregs include, for example, “GWA-900G”, “GWA-910G”, “GHA-679G”, “GHA-679G (S)”, “GZA-71G” (all manufactured by Hitachi Chemical Co., Ltd., Product name) and the like can be used.

[Method of manufacturing printed wiring board]
This invention also provides the manufacturing method of the printed wiring board which has the following process.
(1) A step of laminating a substrate material and the polyimide film with resin to form a laminate for a printed wiring board.
(2) A step of heating the printed wiring board laminate obtained in step (1).
(3) A step having the following step (3-i) or the following steps (3-i) and (3-ii).
(3-i) The process of removing a polyimide film from the laminated body for printed wiring boards obtained at the process (1).
(3-ii) A step of irradiating the laminate for a printed wiring board obtained in the step (3-i) with ultraviolet rays.
(4) A step of forming a circuit pattern on the printed wiring board laminate obtained in step (3).
Hereinafter, each process is demonstrated in order.

[Step (1)]
Examples of a method of laminating and forming the substrate material and the polyimide film with resin include a method of laminating and forming by a laminate method, a press method, or the like.
The laminating method is a method of laminating a substrate material, for example, a circuit of an insulating substrate with a circuit, and a resin composition side of a polyimide film with a resin, and laminating using, for example, a vacuum pressure laminator laminator. When using a vacuum pressurizing laminator laminator, the temperature is preferably about 50 to 300 ° C. and the pressure is 0.2 MPa or more. The preferable upper limit of the pressure varies depending on the thickness of the substrate, the remaining copper ratio, and the like, but is preferably 1.0 MPa or less from the viewpoint of avoiding deformation of the substrate. Further, it is preferable that the degree of vacuum is 15 hPa or less because the embedding property to the inner circuit board tends to be good. The lower the degree of vacuum, the better. However, in consideration of the influence of the apparatus capacity and the waiting time until reaching a predetermined value on productivity, the range of 5 to 10 hPa is preferable. The thermocompression bonding time is preferably about 10 to 90 seconds. If it is 10 seconds or more, the time required for the resin to flow to the inner layer circuit tends to be sufficient, and if it is 90 seconds or less, the productivity tends to be good. A more preferable thermocompression bonding time is 20 to 50 seconds.

  On the other hand, in the case of the press method, the substrate material, for example, the circuit of the insulating substrate with circuit, and the resin composition side of the polyimide film with resin are opposed to each other, for example, about 35 ° C. to 190 ° C. The temperature is raised for about 50 minutes, and the temperature is maintained at a pressure of about 2 to 3 MPa for about 60 to 90 minutes, and then cooled to room temperature for about 30 minutes.

[Step (2)]
Step (2) is a step of heating the printed wiring board laminate obtained in step (1). By this step (2), the resin composition is cured and a resin layer is formed. In this invention, since the polyimide film with resin excellent in heat resistance is used, it can heat-process before the process of removing a polyimide film.
The heating condition is preferably selected in consideration of the following points. That is, if the curing is excessively advanced, the adhesion between the resin layer and the conductor layer may be reduced during the plating process in the subsequent step (4). On the other hand, if the curing is insufficient, the subsequent step (4 It is preferable to consider that the resin layer may be dissolved in the plating solution by being eroded by the alkali treatment solution used during the plating process in (1). Considering the above, preferably the resin composition is cured by heating at 160 to 300 ° C., more preferably 160 to 230 ° C., further preferably 160 to 200 ° C., and preferably about 15 to 180 minutes to form a resin layer. The conditions to do can be adopted.

In addition, after this step (2) and before the step (3-i) of removing the polyimide film, drilling processing such as drilling and laser processing can be performed from the upper surface of the polyimide film as necessary. It is. By drilling from the upper surface of the polyimide film, resin scattering during processing and via ringing by a laser can be suppressed, and the yield is improved. Moreover, by removing smear on the via bottom before peeling the polyimide film, it is possible to prevent the surface roughness of the surface of the resin layer from being increased by the chemical solution.
If it is necessary to remove the smear at the bottom of the via hole after the drilling or laser processing, it can be removed using an oxidizing roughening solution. Examples of the oxidizing roughening liquid include a chromium / sulfuric acid roughening liquid, an alkaline permanganic acid roughening liquid, a sodium fluoride / chromium / sulfuric acid roughening liquid, and a borofluoric acid roughening liquid. In addition, when removing with an oxidizing roughening solution, after the immersion treatment with a solvent or an alkaline solution, or a mixed solution thereof (generally a swelling solution or a pre-dip solution), the removing treatment with an oxidizing roughening solution is also possible. Good. Examples of the solvent include alcohol solvents such as diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, and isopropyl alcohol. Further, the alkaline solution is not particularly limited as long as it is a solution that exhibits alkalinity when dissolved in water, and a sodium hydroxide solution, a potassium hydroxide solution, or the like can be used. Furthermore, as the liquid for mixing the solvent and the alkali liquid, for example, a liquid for mixing sodium hydroxide and diethylene glycol monobutyl ether can be used, and more specifically, sodium hydroxide 3 g / L and diethylene glycol monobutyl ether 300 mL / L. A solution having the composition can be used.

[Step (3)]
Step (3) is a step having the following step (3-i) or the following steps (3-i) and (3-ii).
(3-i) The process of removing a polyimide film from the laminated body for printed wiring boards obtained at the process (1).
(3-ii) A step of irradiating the laminate for a printed wiring board obtained in the step (3-i) with ultraviolet rays.

-Step (3-i)-
There is no restriction | limiting in particular in the method of removing a polyimide film from the laminated body for printed wiring boards, A polyimide film can be removed by well-known methods, such as peeling a polyimide film.

-Step (3-ii)-
In the manufacturing method of the printed wiring board of this invention, it is preferable to irradiate an ultraviolet-ray to the laminated body for printed wiring boards obtained at the process (3-i).
As described above, the resin layer formed from the resin composition containing (A) an epoxy resin and (B) an active ester group-containing compound is a conductor, although the surface roughness is small, that is, the surface roughness is small. Expresses high adhesion to the layer. Although it is not necessarily clear about the mechanism, by irradiating the resin layer which the laminated body for printed wiring boards obtained at the process (3-i) has with an ultraviolet-ray, (B) the active ester group containing compound which is a component The derived ester group is decomposed, and a large number of functional groups such as carbonyl-containing groups are formed on the surface of the resin layer. It is assumed that the functional groups such as carbonyl-containing groups exhibit high adhesion to the conductor layer. The In addition, the number of the functional groups present on the surface of the flexible sheet can be grasped by referring to the amount of oxygen atoms derived from the functional group such as a carbonyl-containing group. The amount of oxygen atoms on the surface of the flexible sheet can be measured by X-ray photoelectron spectroscopy.

Although there are no particular limitations on the irradiation conditions of the ultraviolet rays, for example, using an ultraviolet lamp, preferably an ultraviolet lamp that emits light having a maximum wavelength of 300 to 450 nm, an integrated light quantity of 1,000 to 6,000 mJ / cm under an atmospheric pressure atmosphere. It is preferable to irradiate with ultraviolet rays at about ² . The integrated light quantity (mJ / cm ² ) is calculated by “illuminance (mW / cm ² ) × irradiation time (seconds)”.
From the viewpoint of productivity, the ultraviolet irradiation device is preferably a conveyor type. As the ultraviolet lamp having a maximum wavelength in the range of 300 to 450 nm, for example, a mercury short arc lamp, a high pressure mercury lamp, a capillary type ultra high pressure lamp, a high pressure lamp, a metal halide lamp, or the like can be used. Among these lamps, metal halide lamps having a wide ultraviolet wavelength over the entire region are preferable.

If the cumulative amount of ultraviolet light is 1,000 mJ / cm ² or more, the adhesiveness to the conductor layer tends to be satisfactory without treating the resin layer with an oxidizing roughening solution. If the amount of light is 6,000 mJ / cm ² or less, the adhesiveness with the conductor layer is sufficient and tends to be economically advantageous. From the same viewpoint, the integrated light quantity is more preferably 2,000~5,000mJ / cm ^2, more preferably 2,500~5,000mJ / cm ^2.

[Step (4)]
Step (4) is a step of forming a circuit pattern on the printed wiring board laminate (specifically, on the resin layer) obtained in step (3). Step (4) can be performed by first forming a conductor layer by electroless plating and then forming a circuit pattern.
First, after performing a plating catalyst application treatment for adhering palladium to the resin layer, an electroless plating treatment is performed, and an electroless plating layer preferably having a thickness of 0.3 to 1.5 μm is formed on the resin layer. Form. The plating catalyst application treatment is performed by immersing the insulating film with a resin layer in a palladium chloride plating catalyst solution, and the electroless plating treatment is performed by immersing in an electroless plating solution. As the electroless plating solution, a known electroless plating solution can be used and is not particularly limited, but it is preferable to use an electroless copper plating solution.

  Next, after forming a plating resist pattern on the electroless plating layer, an electrolytic plating process is performed to form an electrolytic plating layer having a desired thickness at a desired location. Thereafter, the plating resist is peeled off, and unnecessary electroless plating layers are removed by etching. Thereby, the conductor layer which consists of an electroless plating layer and an electroplating layer is formed on a resin layer. A known plating resist can be used as the plating resist, and there is no particular limitation. The electrolytic plating treatment can be performed according to a known method, and is not particularly limited, but it is preferable to use an electrolytic copper plating solution as the electrolytic plating solution.

  Since the laminate for a printed wiring board of the present invention has a high adhesive strength between the resin layer and the conductor layer, the conductor layer can be prevented from peeling off in the printed wiring board manufacturing process such as a component mounting process and a soldering process. . Moreover, since the printed wiring board manufactured by the above method using the laminate can form a fine circuit on a resin layer having a small surface roughness, for example, a millimeter wave or a terahertz wave of 30 GHz or more expected in the future. It can be used for electronic devices to be operated, antennas and the like.

  The adhesive strength between the resin layer and the conductor layer of the laminate for a printed wiring board of the present invention is not particularly limited, but is preferably 0.3 kN / m or more, and more preferably 0.5 kN / m or more. Although there is no restriction | limiting in particular in the upper limit of adhesive strength, Usually, 5 kN / m or less, 3 kN / m or less, and 1 kN / m or less may be sufficient. In addition, this adhesive strength is the magnitude | size of the load at the time of peeling at a pulling speed of 50 mm / min in the orthogonal | vertical direction with respect to the surface of a sheet-like flexible sheet | seat of width 10mm and length 100mm.

  Next, the present invention will be described in more detail with reference to the following examples, but these examples are not intended to limit the present invention in any way. In addition, using the evaluation board | substrate for printed wiring boards manufactured by each example, according to the following method, the adhesiveness and surface roughness with a metal thin film were measured and evaluated.

[1. Adhesiveness to metal thin film (conductor layer)]
A part of the conductor layer of the evaluation board produced in each example was etched with a copper etching solution “ammonium persulfate (APS)” (Mitsubishi Gas Chemical Co., Ltd.) to form a circuit pattern having a width of 10 mm and a length of 100 mm. Then, one end of the circuit pattern is peeled off at the interface between the circuit pattern and the resin layer, and is gripped with a gripper. Using “Autograph AG-100C” (manufactured by Shimadzu Corporation), the pulling speed is 50 mm / min in the vertical direction at room temperature. The load at the time of peeling was measured to determine the adhesive strength. The larger the value, the better the adhesion with the metal thin film (conductor layer).

[2. Method for measuring surface roughness (Ra)]
The conductor layer of the evaluation substrate obtained in each example was removed by etching treatment, and the surface roughness (Ra) of the exposed resin layer was measured using a high-precision three-dimensional surface shape measuring device “Wyko NT9100” (manufactured by Veeco). Measurement was performed under the following measurement conditions. In addition, in the comparative example which did not provide the resin layer, the surface roughness of the exposed transparent insulating film was measured.
-Surface roughness measurement conditions-
Internal lens: 1x External lens: 50x Measurement range: 0.120 x 0.095mm
Measurement depth: 10 μm
Measurement method: Vertical scanning type interference method (VSI method)

Example 1
(1) Production of substrate material A 40 μm thick prepreg “GEA-679FG (R)” (manufactured by Hitachi Chemical Co., Ltd.) is stacked on an insulating substrate having a circuit, and copper foil “GTS-12” (Furukawa Electric Co., Ltd.) After making the roughened surface outward, and then stacking the end plate and cushion paper, and using a press machine to heat and cure at 3.0 MPa and 180 ° C. for 1 hour to obtain a laminated sample The copper foil was removed by etching to obtain a substrate material.

(2) Preparation of Resin Composition (Resin Varnish A) Aliphatic Modified Epoxy Resin “Epiclon EXA-4816” (DIC Corporation, Epoxy Resin Having Bisphenol A and Long Chain Aliphatic Skeleton) 100.0 g, Active Ester Group-containing curing agent “EXB-9451” (manufactured by DIC Corporation, ester equivalent 220 g / eq) 44.3 g and 2-phenylimidazole “2PZ” (manufactured by Shikoku Kasei Kogyo Co., Ltd.) 0.30 g were added to methyl ethyl ketone 96 as a solvent. Was dissolved in 4 g to obtain a thermosetting resin composition (resin varnish A) having a solid concentration of 60% by mass.

(3) Preparation of polyimide film provided with resin layer Resin varnish A obtained in (2) above is a die coater on a polyimide film “UPILEX 25S” (Ube Industries, Ltd., thickness 25 μm) as a carrier film. The polyimide film with a resin whose thickness of a resin layer is 4 micrometers was produced by applying for 10 minutes and drying at 140 degreeC for 10 minutes.

(4) Production of laminate for printed wiring board Further, the resin layer of the polyimide film with resin obtained in (3) is opposed to one side of the substrate material obtained in (1) above, so that the vacuum is applied. Using a pressure laminator “MVLP-500” (trade name, manufactured by Meiki Co., Ltd.), lamination was performed under conditions of a temperature of 120 ° C., a pressure of 0.5 MPa, and a pressure bonding time of 30 seconds.
The printed wiring board laminate thus obtained was heat-treated at 180 ° C. for 60 minutes to thermally cure the resin composition, and then the polyimide film was peeled off.
Thereafter, using a conveyor type ultraviolet irradiation device, ultraviolet rays were irradiated with a metal halide lamp (maximum wavelength 350 to 380 nm) so that the integrated light amount became 4,000 mJ / cm ² .

(5) Electroless plating treatment and electrolytic plating treatment As a pretreatment for electroless plating, the laminate for a printed wiring board obtained in (4) above was applied to a conditioner solution “CLC-601” (manufactured by Hitachi Chemical Co., Ltd.). After dipping at 5 ° C. for 5 minutes, it was washed with water and immersed in a pre-dip solution “PD-201” (manufactured by Hitachi Chemical Co., Ltd.) at room temperature for 2 minutes. Next, after being immersed in “HS-202B” (manufactured by Hitachi Chemical Co., Ltd.), which is an electroless plating catalyst containing PdCl ₂ , at room temperature for 10 minutes, it is washed with water and “CUST-” is an electroless copper plating solution. The film was immersed in “201 plating solution” (manufactured by Hitachi Chemical Co., Ltd.) at room temperature for 15 minutes to perform electroless plating. Furthermore, copper sulfate electrolytic plating was performed using a copper sulfate solution.
Thereafter, annealing was performed at 180 ° C. for 30 minutes to form a conductor layer having a thickness of 20 μm on the surface of the resin layer, and an evaluation substrate for a printed wiring board was obtained. Using the evaluation substrate, the adhesion to the metal thin film and the surface roughness were measured and evaluated according to the method described above. The results are shown in Table 1.

(Comparative Example 1)
In Example 1 (4), except that the polyimide film with resin was not laminated (however, the polyimide film was not peeled), an evaluation board for a printed wiring board was prepared, and the method Thus, the adhesion and surface roughness with the metal thin film were measured and evaluated. The results are shown in Table 1.

(Comparative Example 2)
In the same manner as in Example 1 (3), except that a polyethylene terephthalate (PET) film “TR-1” (manufactured by Unitika Ltd., thickness 38 μm) was used instead of the polyimide film, An evaluation substrate was prepared, and the adhesion to the metal thin film and the surface roughness were measured and evaluated according to the method described above. The results are shown in Table 1.

From Table 1, in the evaluation board | substrate for printed wiring boards of Example 1, the surface roughness of the resin layer was small, but the high adhesiveness with the metal thin film was shown.
On the other hand, in the evaluation board | substrate for printed wiring boards of the comparative example 1 which did not laminate | stack the polyimide film with resin, adhesiveness with a metal thin film fell significantly. Moreover, in the comparative example 2 which used PET instead of the polyimide film, the unevenness | corrugation produced by the oligomer component which precipitated and the surface roughness of the resin layer became large.

  Since the polyimide film with resin of the present invention has high adhesiveness to the conductor layer (metal thin film), it is possible to prevent peeling of the circuit pattern in the printed wiring board manufacturing process in the component mounting process, the soldering process, and the like. In addition, the laminate for a printed wiring board using the polyimide film with resin can form a fine circuit pattern on a resin layer having a small surface roughness, and therefore operates in a millimeter wave or a terahertz wave of 30 GHz or more expected in the future. It can be used for electronic devices or antennas.

1 Oligomer component deposited from PET film

Claims (9)

  (A) A resin-coated polyimide film comprising a resin composition containing an epoxy resin and (B) an active ester group-containing compound, and a polyimide film.   The polyimide film with a resin according to claim 1, wherein the (A) epoxy resin has a structural unit derived from an alkylene glycol having 3 or more carbon atoms.   The polyimide film with a resin according to claim 1, wherein the resin composition further contains an inorganic filler. The polyimide film with a resin according to any one of claims 1 to 3, wherein the (B) active ester group-containing compound is an aromatic ester compound having a structural unit represented by the following general formula (V).
  It is a polyimide film provided with the resin layer formed by thermosetting the polyimide film with resin of any one of Claims 1-4, Comprising: The surface roughness of the surface at the side of the polyimide film in this resin layer is The polyimide film provided with the resin layer which is 0.1 micrometer or less.   The laminated body for printed wiring boards formed by carrying out lamination molding of the board | substrate material and the polyimide film with resin of any one of Claims 1-4. The manufacturing method of a printed wiring board which has the following process.
(1) A step of laminating a substrate material and the polyimide film with resin according to any one of claims 1 to 4 to form a laminate for a printed wiring board.
(2) A step of heating the printed wiring board laminate obtained in step (1).
(3) A step having the following step (3-i) or the following steps (3-i) and (3-ii).
(3-i) The process of removing a polyimide film from the laminated body for printed wiring boards obtained at the process (1).
(3-ii) A step of irradiating the laminate for a printed wiring board obtained in the step (3-i) with ultraviolet rays.
(4) A step of forming a circuit pattern on the printed wiring board laminate obtained in step (3).   The manufacturing method of the printed wiring board of Claim 7 whose heating temperature in the said process (2) is 160-300 degreeC. The method for producing a printed wiring board according to claim 7 or 8, wherein an integrated light quantity of ultraviolet rays in the step (3-ii) is 2,000 to 5,000 mJ / cm ² .