JP6257435B2 - LAMINATE, METHOD FOR PRODUCING MULTILAYER PRINTED WIRING BOARD AND MULTILAYER PRINTED WIRING BOARD - Google Patents

Description

  The present invention relates to a laminate, a method for producing a multilayer printed wiring board, and a multilayer printed wiring board.

  In recent years, with the thinning and miniaturization of electronic and electrical equipment, it has been required to mount electronic components on a printed wiring board at a high density, and the conductive layers provided on both main surfaces of the insulating layer have been increased. There is a need to conduct to density. In the manufacturing process of a printed wiring board, the conductive layers are generally conducted through via holes formed in the insulating layer by NC drilling, plasma etching, laser drilling, punching, or the like. However, these processes are not suitable for continuous production of printed wiring boards by roll-to-roll.

On the other hand, if via holes can be formed between conductive layers by chemical etching,
Continuous production of printed wiring boards by two rolls becomes possible. In a conventional process for producing a printed wiring board using chemical etching, a resin composition solution is applied and dried on a conductive layer to provide a resin composition layer, and the conductive layer is formed on the resin composition layer. Laminate. Then, after removing a predetermined region of the conductive layer provided on the resin composition layer with a metal etching solution, the resin layer is etched away with an alkaline solution to form a via hole. Then, after the resin composition is heated and cured, plating is formed on the inner wall of the via hole to electrically connect one conductive layer and the other conductive layer through the via hole. Here, when an aqueous solution of sodium hydroxide or the like is used as the alkaline solution, the step of removing the dry film resist functioning as the etching resist for the conductive layer and the step of etching the resin layer can be accomplished efficiently at the same time (Patent Document 1). reference). The resin composition used for these is required to have alkali resistance because it has alkali processability when forming a via hole and requires a function as an insulating protective film after curing. In Patent Document 1, a combination of a polyimide containing a phenolic hydroxyl group and an oxazoline compound is introduced. Further, Patent Document 2 introduces a combination of a polyimide containing a phenolic hydroxyl group and an epoxy compound, and even if this is used, it has alkali workability when forming a via hole, and has an ability of having alkali resistance after curing. Can be granted.

International Publication No. 2013/108890 Pamphlet JP 2009-147116 A

  When forming a via hole by alkaline etching, if the alkali etching is performed for a sufficient amount of time so that no residue remains on the bottom of the via, the overetching amount on the via hole side wall is significantly increased in the resin layer having isotropic alkali solubility. There is. If it becomes so, the connection reliability of a via hole will fall. The non-photosensitive resin compositions described in Patent Documents 1 and 2 have a further problem in terms of the amount of overetching that is acceptable in terms of via hole quality.

  The present invention has been made in view of the above points, and a laminated body from which a multilayer printed wiring board having good connection reliability of via holes can be obtained, a method for producing a multilayer printed wiring board using the laminated body, and the method. It aims at providing the manufactured multilayer printed wiring board.

  The laminate of the present invention comprises a base material that is a conductor and a thermosetting resin layer provided on the base material, and the thermosetting resin layer contains an alkali-soluble resin and has a minimum melt viscosity. Is 700 Pa · s or more and 2300 Pa · s or less, and the temperature range showing the minimum melt viscosity is 150 ° C. or more and 200 ° C. or less.

  With such a configuration, since the minimum melt viscosity of the thermosetting resin layer is 700 Pa · s or more and 2300 Pa · s or less, an appropriate flow of the resin layer occurs during thermosetting in the heating step. In addition, since the temperature range showing the lowest melt viscosity is 150 ° C. or more and 200 ° C. or less, the resin layer flows at a general heating process temperature, and even if overetching occurs due to alkali etching, the resin is present at the missing portion. The composition layer can flow in sufficiently, and the final overetching amount can be reduced.

  In the laminate of the present invention, it is preferable that the thermosetting resin layer has a melt viscosity at 40 ° C. of 10,000 Pa · s or more.

  In the laminate of the present invention, the dissolution rate of the thermosetting resin layer in a 3% by mass sodium hydroxide aqueous solution at 45 ° C. is preferably 0.15 μm / second or more and 0.50 μm / second or less.

  In the laminate of the present invention, it is preferable that the minimum melt viscosity is 1500 Pa · S or more and 1700 Pa · s or less, and the dissolution rate is 0.15 μm / second or more and 0.25 μm / second or less.

  In the laminate of the present invention, the alkali-soluble resin is preferably a polyimide having a phenolic hydroxyl group.

  In the laminate of the present invention, the phenolic hydroxyl group preferably has a structure represented by the following general formula (1).

（一般式（１）中、Ｘは、単結合又は−Ｃ（−ＣＦ_３）_２−を表し、ｋは、１から４の整数を表す。）

(In General Formula (1), X represents a single bond or —C (—CF ₃ ) ₂ —, and k represents an integer of 1 to 4.)

  In the laminate of the present invention, the polyimide preferably has a structure represented by the following general formula (2).

（一般式（２）中、Ｒは、二価の有機基を表す。）

(In general formula (2), R represents a divalent organic group.)

  In the laminate of the present invention, the thermosetting resin layer preferably contains an oxazoline compound.

  In the laminate of the present invention, the base material is preferably a copper foil.

  The method for producing a multilayer printed wiring board according to the present invention includes a step of laminating the thermosetting resin layer side of the laminate described above on a substrate having wiring, and a dry film resist on the substrate side of the laminate. Forming a resist mask, forming a conformal mask by removing a part of the base material by etching using the resist mask, and forming the thermosetting resin layer through the conformal mask. Removing a part with an alkaline solution to form a via hole, removing the resist mask, and then performing an acid cleaning; and thermosetting the thermosetting resin layer to form a cured resin layer; and It is characterized by comprising.

  The multilayer printed wiring board of the present invention is manufactured by the manufacturing method described above.

  ADVANTAGE OF THE INVENTION According to this invention, the laminated body from which the multilayer printed wiring board with favorable connection reliability of a via hole is obtained, the manufacturing method of the multilayer printed wiring board using the said laminated body, and the multilayer printed wiring board manufactured by the said method are provided. can do.

It is a cross-sectional schematic diagram which shows each process of the manufacturing method of the double-sided flexible wiring board which concerns on this Embodiment. It is a cross-sectional schematic diagram which shows each process of the manufacturing method of the multilayer flexible wiring board which concerns on this Embodiment. It is a cross-sectional schematic diagram which shows each process of via-hole formation in the manufacturing method of the multilayer flexible wiring board which concerns on this Embodiment. It is explanatory drawing for demonstrating the determination method of the blind via hole shape in the Example of this invention.

  Hereinafter, embodiments of the present invention will be described in detail. In addition, this invention is not limited to the following embodiment, It can implement by changing variously within the range of the summary.

<Outline of the present embodiment>
The laminate according to the present embodiment includes a base material that is a conductor, and a thermosetting resin layer provided on the base material, and the thermosetting resin layer includes an alkali-soluble resin, The minimum melt viscosity is 700 Pa · s or more and 2300 Pa · s or less, and the temperature range showing the minimum melt viscosity is 150 ° C. or more and 200 ° C. or less.

  With the configuration as described above, the laminate according to the present embodiment exhibits suitable performance as a material for the interlayer insulating layer of the multilayer printed wiring board.

  For example, in the production of a multilayer printed wiring board, first, a laminate composed of a thermosetting resin layer (hereinafter simply referred to as a resin layer) and a substrate is laminated so as to cover the wiring of the substrate having wiring. To do. A resist mask made of a dry film resist (or liquid resist) is formed on the substrate. A conformal mask is formed by removing a part of the substrate by etching using a resist mask. A part of the resin layer is removed with an alkaline solution through a conformal mask to form a via hole, and the resist mask is removed (this process is called alkali etching). Next, the resin layer is thermally cured to form a cured resin layer.

  In the production of the multilayer printed wiring board as described above, when the laminate according to the present embodiment is used, the minimum melt viscosity of the resin layer is 700 Pa · s or more and 2300 Pa · s or less. Sometimes moderate flow of the resin layer occurs. In addition, since the temperature range showing the lowest melt viscosity is 150 ° C. or more and 200 ° C. or less, the resin layer flows at a general heating process temperature, and even if overetching occurs due to alkali etching, the resin is present at the missing portion. The composition layer can flow in sufficiently, and the final overetching amount can be reduced.

<Manufacturing method of multilayer printed wiring board>
The manufacturing method of the multilayer printed wiring board concerning this Embodiment is demonstrated in detail with reference to an accompanying drawing. First, the manufacturing method of the double-sided flexible wiring board 10 will be described with reference to FIG. FIG. 1 is a schematic cross-sectional view showing each step of the method for manufacturing a double-sided flexible wiring board according to the present embodiment. In the manufacturing method of this double-sided flexible wiring board 10, the laminated body 11 which concerns on this Embodiment is used (refer FIG. 1A). The laminate 11 includes a base material 12a (for example, copper foil F2-WS (12 μm)) and a resin layer 14 (for example, thickness 25 μm) provided on the base material 12a and containing an alkali-soluble resin. Prepare.

  In the laminate 11 according to the present embodiment, the thermosetting resin composition dissolved in an organic solvent is applied onto the base material 12a, and then heated at 95 ° C. for 12 minutes, and the organic material contained in the resin layer 14 It is manufactured by removing the solvent by drying.

  Next, the laminate 13 is obtained by, for example, vacuum pressing the base material 12b on the resin layer 14 of the laminate 11 at 120 ° C. for 2 minutes under the condition of 4 MPa (see FIG. 1B). Next, a photosensitive resist mask made of a dry film resist is formed on the base materials 12 a and 12 b of the laminate 13. The resist mask is exposed and developed, and a part of the base materials 12a and 12b is removed by etching using the resist mask to form a conformal mask. Next, through the conformal mask, the resin layer 14 exposed at the etching sites of the base materials 12a and 12b is removed by etching with a 3 mass% sodium hydroxide aqueous solution or the like at 45 ° C. After removing the mask, acid cleaning is performed with 1% hydrochloric acid or the like (see FIG. 1C).

  Next, by using a curing and drying furnace, for example, by heating at 180 ° C. for 1 hour, the resin layer 14 is thermally cured (hereinafter also referred to as cure) to form the cured resin layer 16.

  Next, the base materials 12a and 12b are electrically connected by a method such as electrolytic plating after carbon black is attached to the inner wall of the through hole 15. Next, the double-sided flexible wiring board 10 is manufactured by patterning the base materials 12a and 12b by a subtractive method or the like to form a circuit (see FIG. 1D).

  Next, a method for manufacturing the multilayer flexible wiring board 1 will be described with reference to FIG. FIG. 2 is a schematic cross-sectional view showing each step of the method for manufacturing a multilayer flexible wiring board according to the present embodiment. In the manufacturing method of this multilayer flexible wiring board 1, the double-sided flexible wiring board 10 obtained by the manufacturing method shown in FIG. 1 is used (see FIG. 2A). Here, a commercially available double-sided copper-clad laminate (Espanex (registered trademark) M: insulating layer thickness 25 μm, manufactured by Nippon Steel Chemical Co., Ltd.) may be used. The double-sided flexible wiring board 10 includes a cured resin layer 16 and a pair of base materials (copper foils) 12 a and 12 b provided on both main surfaces of the cured resin layer 16.

  First, the laminated bodies 21a and 21b according to the present embodiment are laminated on the base materials 12a and 12b (see FIG. 2B). The laminates 21a and 21b include base materials 22a and 22b (copper foil: F2-WS (18 μm), manufactured by Furukawa Circuit Foil Co., Ltd.), and the above-described thermosetting resin composition and organic solvent on the base materials 22a and 22b. The resin layer 23a, 23b provided by applying a thermosetting resin composition solution containing the organic solvent and removing the organic solvent.

  The laminated bodies 21a and 21b are laminated on the double-sided flexible wiring board 10 by a method such as vacuum pressing at 120 ° C. for 2 minutes under a condition of 4 MPa. Thereby, the resin layers 23a and 23b are provided on the base materials 12a and 12b of the double-sided flexible wiring board 10, respectively, and the base materials 22a and 22b are sequentially laminated on the resin layers 23a and 23b (FIG. 2C). reference).

  In this laminating process, the resin layers 23a and 23b are heated under conditions that do not allow the thermosetting of the resin layers 23a and 23b (for example, at 120 ° C. for about 2 minutes) to melt the resin layers 23a and 23b. Embed and crimp between patterns. Further, the holes in the through holes 15 formed in the double-sided flexible wiring board 10 may be completely closed in advance with electrolytic plating, conductive paste, or insulating resin for filling holes, but are filled with the resin layers 23a and 23b at the time of lamination. You can also

  Next, a photosensitive resist mask (not shown) made of a dry film resist is formed on the base materials 22a and 22b. The resist mask is exposed and developed, and a part of the base materials 22a and 22b is removed by etching using the resist mask to form a conformal mask. Next, the resin layers 23a and 23b exposed at the etching sites of the base materials 22a and 22b through the conformal mask are etched with a 3% by mass sodium hydroxide aqueous solution at 45 ° C. to form the via hole 24, and at the same time, the resist The layer is peeled off and washed with 1% hydrochloric acid or the like (see FIG. 2D).

  Next, by using a curing / drying furnace, for example, by heating at 180 ° C. for 1 hour, the resin layers 23a and 23b are thermally cured to form resin cured product layers 31a and 31b, and outer layer substrates 26a and 26b are obtained.

  Next, the resin cured material layers 31a and 31b on the inner walls of the via holes 24 are plated to electrically connect the base material 12a and the base material 22a and between the base material 12b and the base material 22b. To do.

  Next, the substrates 22a and 22b are patterned by a subtractive method or the like to form a circuit (see FIG. 2E). Next, surface treatment such as formation of the cover coat 25 is performed to manufacture the multilayer flexible wiring board 1 (see FIG. 2F).

  According to the laminated body 11 which concerns on this Embodiment, since the resin layer 14 contains alkali-soluble resin, it is used universally for peeling of the dry film of the wiring process in the manufacturing process of a flexible printed wiring board, for example Blind vias or via holes such as through holes 15 can be processed using the aqueous sodium hydroxide solution.

  However, in the method for manufacturing a multilayer printed wiring board using the laminate 11 according to the present embodiment, it is possible to process a via hole with an alkaline solution, but the present invention is not necessarily limited thereto, and the conventional drill is used. Laser processing is also possible.

  In the following description of the present embodiment, the term “via hole” includes a through via hole, that is, a through hole and a non-through via hole. The non-through via hole includes a blind via that is a via hole used for connection from the outer layer to the inner layer and a buried via that is a via hole used for connection between the inner layers.

<Laminated body>
Next, details of the laminated body 11 according to the present embodiment will be described. The laminate 11 according to the present embodiment includes a base material 12a that is a conductor, and a resin layer 14 provided on the base material 12a.

(1) Resin layer The resin layer 14 contains alkali-soluble resin. The resin layer 14 has a minimum melt viscosity of 700 Pa · s to 2300 Pa · s, and a temperature range indicating the minimum melt viscosity is 150 ° C. to 200 ° C.

  The melt viscosity here is, for example, a value measured with a viscoelasticity measuring device (rheometer).

  In order to further reduce the amount of over-etching after thermosetting, the minimum melt viscosity is preferably 800 Pa · s or more and 2000 Pa · s or less, in order to impart an appropriate resin fluidity, and 1500 Pa · s or more and 1700 Pa · s or less. The following is more preferable.

  Methods for adjusting the minimum melt viscosity include methods such as adjusting the amount of plasticizer added in the resin composition, adjusting the molecular weight of the alkali-soluble resin, and adjusting the flexibility of the alkali-soluble resin. .

  The resin layer 14 preferably has a melt viscosity at 40 ° C. of 10,000 Pa · s or more from the viewpoint of easy handling as a laminate.

  Furthermore, the resin layer 14 has a dissolution rate in a 3% by mass sodium hydroxide aqueous solution at 45 ° C. of 0.15 μm / second or more and 0.50 μm / second or less from the viewpoint of adapting to a general dry film peeling time. It is preferably 0.15 μm / sec or more and more preferably 0.25 μm / sec or less.

  Thus, the minimum time required for dissolving and removing the resin composition layer (hereinafter referred to as the minimum alkaline etching time) when simultaneously forming the via hole using the alkaline solution and peeling the dry film resist is the dry film. It matches the time required for resist stripping (hereinafter referred to as DF stripping time). When the minimum alkaline etching time and the DF peeling time are equal or close to the same state, it is referred to as “adapted”. Ideally, the minimum alkali etching time and the DF peeling time are equal.

  The DF stripping time is calculated by multiplying the lifting point of the dry film resist by a safety factor. The lifting point refers to the time when the dry film resist begins to peel off when the dry film resist is immersed in an alkaline solution. Moreover, a general safety factor is 1.5-3.

  Since the resin layer 14 has a very good via hole shape, the minimum melt viscosity is 1500 Pa · S or more and 1700 Pa · s or less, and the dissolution rate is 0.15 μm / second or more and 0.25 μm / second or less. Is particularly preferred.

(2) Base material As the base material 12a which is a conductor, known metal foils and alloy foils are applicable, but copper foils such as electrolytic copper foil and rolled copper foil are preferable from the viewpoint of wiring formability. Furthermore, when using for fine wiring formation property and especially a flexible substrate, a copper foil with a thickness of 18 μm or less is preferable from the viewpoint of folding resistance. The copper foil surface may be subjected to a surface treatment such as a roughening treatment, a known plating treatment such as nickel or zinc, a chromate treatment, an aluminum alcoholate treatment, an aluminum chelate treatment, or a silane coupling agent treatment.

<Method for producing laminate>
Next, the manufacturing method of the laminated body 11 which concerns on this Embodiment is demonstrated. First, a resin composition solution described later is applied onto the conductor by any method. Examples of the coating method include bar coating, roller coating, die coating, blade coating, dip coating, doctor knife, spray coating, flow coating, spin coating, slit coating, and brush coating. After coating, a heat drying treatment is performed in order to remove the solvent in the resin composition applied onto the substrate 12a.

  Although it does not specifically limit about the aspect of a heating, In order to make it soluble in alkaline aqueous solution, it is preferable to heat for 1 minute-60 minutes at 50 to 140 degreeC, and you may implement by a vacuum drying method etc.

  Further, an arbitrary antifouling or protective cover film may be provided on the resin layer 14 of the laminate 11 according to the present embodiment. As a cover film, if it is a film which protects resin compositions, such as low density polyethylene, it will not be limited.

  The resin layer 14 of the laminate 11 according to the present embodiment is soluble in an alkaline aqueous solution even after being heated at 50 ° C. to 140 ° C. for 1 minute to 60 minutes. For this reason, the laser drilling process etc. which are used by manufacture of a flexible printed wiring board are unnecessary, and it can use suitably as an interlayer insulation material at the time of carrying out a via-hole process and a through-hole process with alkaline aqueous solution.

  Moreover, in the laminated body 11 which concerns on this Embodiment, it is preferable that the thickness of the resin layer 14 is 5 micrometers-50 micrometers. When the thickness of the resin layer 14 is 5 μm or more, handling is easy, and when the thickness of the resin layer 14 is 50 μm or less, folding and incorporation are easy when used for a flexible printed wiring board.

  Moreover, the laminated body 13 which provided the base material 12b in the resin layer 14 side of the laminated body 11 which comprises the base material 12a and the resin layer 14 provided on the base material 12a is used for manufacture of a wiring board. Can do. That is, the method for manufacturing a wiring board using the laminate 13 includes a step of patterning the base materials 12a and 12b of the laminate 13, a step of patterning the resin layer 14 using the patterned base materials 12a and 12b as a mask, and patterning. The step of thermally curing the resin layer 14 and the step of patterning the base materials 12a and 12b are included. Moreover, in the process of thermosetting the resin layer 14, it is preferable to heat at 150 to 220 ° C. for 10 to 100 minutes.

<Resin composition>
Next, details of the resin composition forming the resin layer 14 will be described. Although the composition of the resin composition according to the present embodiment is not particularly limited as long as it contains an alkali-soluble resin, a preferred embodiment includes an embodiment containing (A) an alkali-soluble resin and (B) a thermal crosslinking agent. Thereby, when the resin cured product layer 16 is formed in the heating step, a crosslinking reaction between (A) the acidic hydroxyl group of the alkali-soluble resin and (B) the crosslinkable functional group in the thermal crosslinking agent at the initial stage of thermal curing. Gradually proceeds, and the fluidity of the cured resin layer 16 increases for a certain period of time. As a result, even if overetching occurs in alkali etching, the resin composition can sufficiently flow into the missing portion, and the final overetching amount can be reduced. Furthermore, (C) a flame retardant, (D) a plasticizer, and (F) other additives can be included as needed. Hereinafter, the components contained in the resin composition will be described in detail.

(A) Alkali-soluble resin (A) The alkali-soluble resin is not particularly limited as long as it is soluble in alkali. Examples of the (A) alkali-soluble resin include (A-1) polyimide, (A-2) polyamide, (A-3) modified polyurethane, phenol resin, resol resin, and novolak resin. Among these, (A-1) polyimide, (A-2) polyamide, (A-3) modified polyurethane and the like are preferable from the viewpoints of flexibility and folding resistance.

(A-1) Polyimide (A-1) It is preferable that a polyimide has acidic functional groups, such as a carboxyl group and a phenolic hydroxyl group, from an alkali-soluble viewpoint, and a phenolic hydroxyl group from a reactive and availability viewpoint. More preferably. In addition, the phenolic hydroxyl group-containing polyimide preferably has a structure represented by the following general formula (1) from the viewpoints of solubility in an organic solvent, reactivity during polymerization, availability, and the like.

（一般式（１）中、Ｘは、単結合、−Ｃ（−ＣＦ_３）_２−を表し、ｋは１から４の整数を表す。）

(In general formula (1), X represents a single bond, —C (—CF ₃ ) ₂ —, and k represents an integer of 1 to 4.)

  In addition, from the viewpoint that it is possible to control the alkali dissolution rate because it can impart an appropriate hydrophobicity to the resin layer 14, and it is possible to control the melt viscosity during the heating step because it can provide an appropriate flexibility ( A-1) It is preferable that the polyimide has a structure represented by the following general formula (2).

（一般式（２）中、Ｒは、二価の有機基を表す。）

(In general formula (2), R represents a divalent organic group.)

  The acid dianhydride having the structure represented by the general formula (2) has increased hydrophilicity due to the ether chain-containing acid dianhydride, and also has hydrophobicity due to the substitution position with the aromatic being in the para position. Will increase. It is inferred that moderate hydrophobicity is imparted to the resin composition due to hydrophilic and hydrophobic factors. Moreover, moderate flexibility is provided by having a bent structure.

  The amount of the acid dianhydride having the structure represented by the general formula (2) contained in the polyimide (A-1) from the resin composition is determined by placing the resin composition in an organic solvent such as acetone or ethanol. It can be specified by dissolving and separating the (A-1) polyimide, which is an insoluble component, by reprecipitation and analyzing it by pyrolysis GC / MS. Moreover, in the resin cured product after thermosetting, after separating the crosslinked body of (A-1) polyimide and (B) thermal crosslinking agent by the same reprecipitation treatment as described above, this is thermally decomposed in the same manner as described above. It can be specified by analyzing with GC / MS.

  (A-1) A polyimide is obtained by making tetracarboxylic dianhydride and diamine react.

  As the tetracarboxylic dianhydride, 2,2-bis ((4- (3,4-dicarboxyphenoxy) phenyl) propane dianhydride having the structure of the general formula (2) is more preferable. It may be used in combination with other acid dianhydrides.

  Examples of tetracarboxylic dianhydrides that can be used in combination include those conventionally known, such as 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 2,3,3 ′. , 4′-biphenyltetracarboxylic dianhydride, 2,2 ′, 3,3′-biphenyltetracarboxylic dianhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, 2, 2 ', 3,3'-benzophenone tetracarboxylic dianhydride, 3,3'-oxydiphthalic dianhydride, 4,4'-oxydiphthalic dianhydride, bis (3,4-dicarboxyphenyl) sulfone Anhydride, bicyclo [2,2,2] oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, 1,2,3,4-butanetetracarboxylic dianhydride, 5, 5'-methylene-bi (Anthranic acid), pyromellitic dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 2,2-bis (2,3-dicarboxyphenyl) propane dianhydride 1,1-bis (3,4-dicarboxyphenyl) ethane dianhydride, 1,1-bis (2,3-dicarboxyphenyl) ethane dianhydride, bis (3,4-dicarboxyphenyl) Methane dianhydride, bis (2,3-dicarboxyphenyl) methane dianhydride, 2,2-bis (4- (4-aminophenoxy) phenyl) propane, 1,3-dihydro-1,3-dioxo- 5-isobenzofurancarboxylic acid-1,4-phenylene ester, 4- (2,5-dioxotetrahydrofuran-3-yl) -1,2,3,4-tetrahydronaphthalene-1,2-di Rubonic anhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 2,3,5,6-pyridinetetracarboxylic acid Anhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, 2,2-bis (3,4-dicarboxyphenyl) hexafluoropropane dianhydride, 2,2-bis (4- (3 , 4-Dicarboxyphenoxy) phenyl) hexafluoropropane dianhydride, 2,2-bis (4- (3,4-dicarboxybenzoyloxy) phenyl) hexafluoropropane dianhydride, 2,2′-bis ( Trifluoromethyl) -4,4′-bis (3,4-dicarboxyphenoxy) biphenyl dianhydride, cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentane Tetracarboxylic dianhydride, 2,3,5,6-cyclohexanetetracarboxylic dianhydride, 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene-1,2 -Dicarboxylic dianhydride etc. are mentioned.

  Further, from the viewpoint of flexibility, polydimethylsiloxane-containing acid dianhydride or polyoxyalkylene skeleton-containing acid dianhydride may be used.

  Examples of the diamine containing a phenolic hydroxyl group include 3,3′-diaminobiphenyl-4,4′-diol, 3,3′-diaminobiphenyl-4,4′-diol represented by the above general formula (1), 4,3′-diaminobiphenyl-3,4′-diol, 4,4′-diaminobiphenyl-3,3 ′, 5,5′-tetraol, 3,3′-diaminobiphenyl-4,4 ′, 5 , 5′-tetraol, 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane, 2,2′-bis (3-amino-2,4-dihydroxyphenyl) hexafluoropropane, 2, 2′-bis (4-amino-3,5-dihydroxyphenyl) hexafluoropropane and the like can be mentioned. These diamines may be used alone or in combination of two or more.

  Among these diamines, (A-1) 3,3′-diaminobiphenyl-4,4′-diol, 2,2-bis (2, from the viewpoint of solubility of polyimide, insulation reliability, polymerization rate and availability 3-Amino-4-hydroxyphenyl) hexafluoropropane is preferred.

  From the viewpoint of flexibility, α, ω-bis (2-aminoethyl) polydimethylsiloxane, α, ω-bis (3-aminopropyl) polydimethylsiloxane, α, ω-bis (4-aminobutyl) poly Silicone diamines such as dimethylsiloxane, α, ω-bis (4-aminophenyl) polydimethylsiloxane, and α, ω-bis (3-aminopropyl) polydiphenylsiloxane can be used in combination. PAM-E, KF-8010, X-22-161A, X-22-1660B-3 and the like manufactured by the company may be mentioned.

  Similarly, from the viewpoint of flexibility, polyoxyethylene diamine, polyoxypropylene diamine, polyoxytetramethylene diamine, and other polyoxyalkylene diamines (polyalkyl ether diamines) containing oxyalkylene groups having different numbers of carbon chains are combined. Can be used. Commercially available products include polyoxyethylene diamines such as Jeffermin ED-600, ED-900, ED-2003, EDR-148, and HK-511 manufactured by Huntsman, Inc., Jeffermin D-230, D-400, D- 2000, D-4000, polyoxypropylene diamines such as polyetheramine D-230, D-400, D-2000 manufactured by BASF Germany, and polyoxyls such as Jeffamine XTJ-542, XTJ-533, XTJ-536 Examples having a tetramethylene group include (A-1) a solvent solubility of polyimide and a polyoxytetramethylene group in that the melt viscosity at the time of thermosetting can be lowered and the resin flow can be promoted. Including Jeffamine XTJ-542, XTJ-533, XTJ-536 Arbitrariness.

  Further, as the diamine, other conventionally known diamines can be used within the range where the effects of the present embodiment are exhibited. Other diamines include, for example, 3,3′-diaminobenzophenone, 4,4′-diaminobenzophenone, 3,3′-diaminodiphenyl ether, 4,4′-diaminodiphenyl ether, 1,3-bis (3-aminophenoxy ) Benzene, 1,4-bis (4-aminophenoxy) benzene, bis (3- (3-aminophenoxy) phenyl) ether, bis (4- (4-aminophenoxy) phenyl) ether, 1,3-bis ( 3- (3-aminophenoxy) phenoxy) benzene, 1,4-bis (4- (4-aminophenoxy) phenoxy) benzene, bis (3- (3- (3-aminophenoxy) phenoxy) phenyl) ether, bis (4- (4- (4-Aminophenoxy) phenoxy) phenyl) ether, 1,3-bis (3- ( -(3-aminophenoxy) phenoxy) phenoxy) benzene, 1,4-bis (4- (4- (4-aminophenoxy) phenoxy) phenoxy) benzene, 4,4'-bis (3-aminophenoxy) biphenyl, 4,4′-bis (4-aminophenoxy) biphenyl, 2,2-bis [4- (3-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- (3-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoropropane, 2,2-bis [4- (4-aminophenoxy) phenyl]- 1,1,1,3,3,3-hexafluoropropane, m-phenylenediamine, o-phenylenediamine, p-phenylenediamine, bis (3-aminopheny ) Sulfide, bis (4-aminophenyl) sulfide, bis (3-aminophenyl) sulfoxide, bis (4-aminophenyl) sulfoxide, bis (3-aminophenyl) sulfone, bis (4-aminophenyl) sulfone, 2, Examples thereof include diamines such as 2-bis [4- (3-aminophenoxy) phenyl] butane.

  As content of diamine represented by the said General formula (1), it is preferable that the theoretical value of the phenolic hydroxyl value of (A-1) polyimide exists in the range of 20-100 mgKOH / g. When the theoretical value of the phenolic hydroxyl value is in the range of 20 to 100 mgKOH / g, the resin composition can be imparted with appropriate alkali processability, and the optimum time for alkali etching is reduced to a general DF peeling time. In this respect, more preferably in the range of 40-80 mg KOH / g.

  Next, a method for producing (A-1) polyimide will be described. (A-1) The manufacturing method of polyimide which concerns on this Embodiment can apply all the methods which can manufacture (A-1) polyimide including a well-known method. Among these, it is preferable to perform the reaction in an organic solvent. As a solvent used in such a reaction, for example, N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, γ-butyrolactone, 1,2-dimethoxyethane, tetrahydrofuran, 1,3 -Dioxane, 1,4-dioxane, dimethyl sulfoxide, benzene, toluene, xylene, mesitylene, phenol, cresol, ethyl benzoate, butyl benzoate and the like. These may be used alone or in combination of two or more.

  As a density | concentration of the reaction raw material in this reaction, it is 2 mass%-80 mass% normally, Preferably it is 20 mass%-50 mass%.

  Although not particularly limited, the total molar ratio of the tetracarboxylic dianhydride to be reacted and the diamine is preferably in the range of 0.8 to 1.2. Within this range, the molecular weight can be increased, and the elongation and the like are excellent. The molar ratio is preferably 0.9 to 1.1, more preferably 0.92 to 1.07.

  The weight average molecular weight of the polyimide precursor is preferably 5000 or more and 100,000 or less. Here, the weight average molecular weight refers to a molecular weight measured by gel permeation chromatography using polystyrene having a known number average molecular weight as a standard. The weight average molecular weight is more preferably from 10,000 to 60,000, and most preferably from 15,000 to 50,000. When the weight average molecular weight is 5,000 or more and 100,000 or less, the strength and elongation of the protective film obtained using the resin composition is improved, and the mechanical properties are excellent. Furthermore, it can be applied without bleeding at a desired film thickness during coating.

  (A-1) The polyimide is obtained by the following method. First, a polyimide precursor having a polyamic acid structure is produced by subjecting a reaction raw material to a polycondensation reaction from room temperature to 80 ° C. Next, this polyimide precursor is heated to 100 ° C. to 400 ° C. to imidize, or chemically imidized using an imidizing agent such as acetic anhydride, thereby having a repeating unit structure corresponding to polyamic acid. (A-1) A polyimide is obtained. In the case of imidization by heating, in order to remove water produced as a by-product, dehydration may be performed under reflux using a Dean-Stark dehydrator in the presence of an azeotropic agent (for example, toluene or xylene). preferable.

  Moreover, by performing reaction at 80 degreeC-220 degreeC, the production | generation of a polyimide precursor and a thermal imidation reaction can be advanced together, and (A-1) polyimide can also be obtained. That is, a diamine component and an acid dianhydride component are suspended or dissolved in an organic solvent and reacted under heating at 80 ° C. to 220 ° C. to cause both generation of a polyimide precursor and dehydration imidization. (A-1) It is also preferable to obtain a polyimide.

  Moreover, as (A-1) polyimide which concerns on this Embodiment, it is preferable from the viewpoint of the storage stability of a resin composition that it is further end-capped with the end-capping agent which consists of a monoamine derivative or a carboxylic acid derivative. .

  Examples of the end capping agent comprising a monoamine derivative include aniline, o-toluidine, m-toluidine, p-toluidine, 2,3-xylidine, 2,6-xylidine, 3,4-xylidine, and 3,5-xylidine. O-chloroaniline, m-chloroaniline, p-chloroaniline, o-bromoaniline, m-bromoaniline, p-bromoaniline, o-nitroaniline, p-nitroaniline, m-nitroaniline, o-aminophenol P-aminophenol, m-aminophenol, o-anisidine, m-anisidine, p-anisidine, o-phenetidine, m-phenetidine, p-phenetidine, o-aminobenzaldehyde, p-aminobenzaldehyde, m-aminobenzaldehyde, o-aminobenzonitrile, p-aminobenzonitrile Lyl, m-aminobenzonitrile, 2-aminobiphenyl, 3-aminobiphenyl, 4-aminobiphenyl, 2-aminophenylphenyl ether, 3-aminophenylphenyl ether, 4-aminophenylphenyl ether, 2-aminobenzophenone, 3 -Aminobenzophenone, 4-aminobenzophenone, 2-aminophenyl phenyl sulfide, 3-aminophenyl phenyl sulfide, 4-aminophenyl phenyl sulfide, 2-aminophenyl phenyl sulfone, 3-aminophenyl phenyl sulfone, 4-aminophenyl phenyl sulfone , Α-naphthylamine, β-naphthylamine, 1-amino-2-naphthol, 5-amino-1-naphthol, 2-amino-1-naphthol, 4-amino-1-naphthol, 5-amino Aromatic monoamines such as 2-naphthol, 7-amino-2-naphthol, 8-amino-1-naphthol, 8-amino-2-naphthol, 1-aminoanthracene, 2-aminoanthracene and 9-aminoanthracene It is done. Of these, aniline derivatives are preferably used. These may be used alone or in combination of two or more.

  Examples of the terminal blocking agent made of a carboxylic acid derivative mainly include carboxylic anhydride derivatives. As carboxylic anhydride derivatives, phthalic anhydride, 2,3-benzophenone dicarboxylic anhydride, 3,4-benzophenone dicarboxylic anhydride, 2,3-dicarboxyphenyl phenyl ether anhydride, 3,4-dicarboxyphenyl Phenyl ether anhydride, 2,3-biphenyl dicarboxylic acid anhydride, 3,4-biphenyl dicarboxylic acid anhydride, 2,3-dicarboxyphenyl phenyl sulfone anhydride, 3,4-dicarboxyphenyl phenyl sulfone anhydride, 2 , 3-dicarboxyphenyl phenyl sulfide anhydride, 3,4-dicarboxyphenyl phenyl sulfide anhydride, 1,2-naphthalenedicarboxylic anhydride, 2,3-naphthalenedicarboxylic anhydride, 1,8-naphthalenedicarboxylic acid Anhydride, 1,2-anthracene dicarboxylic acid Anhydride, 2,3-anthracene dicarboxylic acid anhydride, 1,9-aromatic dicarboxylic acid anhydrides such as anthracene dicarboxylic acid anhydride. Of these aromatic dicarboxylic acid anhydrides, phthalic anhydride is preferably used. These may be used alone or in combination of two or more.

  The obtained polyimide solution may be used as it is without removing the solvent, and may further be used as a resin composition solution according to the present embodiment by blending necessary solvents, additives and the like.

(A-2) Polyamide (A-2) The polyamide preferably has a phenolic hydroxyl group from the viewpoint of alkali solubility and can be synthesized by the reaction of a dicarboxylic acid and a diamine.

  Examples of the dicarboxylic acid having a phenolic hydroxyl group include 5-hydroxyisophthalic acid and 4-hydroxyisophthalic acid.

  Specific examples of other dicarboxylic acids include phthalic acid, isophthalic acid, terephthalic acid, 4,4′-oxydibenzoic acid, 4,4′-biphenyldicarboxylic acid, 3,3′-, methylene dibenzoic acid, 4,4′-methylene dibenzoic acid, 4,4′-thiodibenzoic acid, 3,3′-carbonyl dibenzoic acid, 4,4′-carbonyl dibenzoic acid, 4,4′-sulfonyldibenzoic acid, 1,5-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 1,2-naphthalenedicarboxylic acid, 2,2′-bis (3-carboxyphenyl) hexafluoropropane, 2, Examples thereof include, but are not limited to, 2′-bis (4-carboxyphenyl) hexafluoropropane. Moreover, you may use these 1 type or in mixture of 2 or more types. Moreover, it is preferable to use what made the said dicarboxylic acid into acid chloride from a reactive viewpoint with diamine. A commercially available dicarboxylic acid chloride can be used, but it can also be synthesized by a known method using an acid chloride reagent such as thionyl chloride as the dicarboxylic acid.

  Examples of the diamine containing a phenolic hydroxyl group include 3,5-diaminophenol, 3,3′-diaminobiphenyl-4,4′-diol, 3,3′-diaminobiphenyl-4,4′-diol, 4 , 3′-diaminobiphenyl-3,4′-diol, 4,4′-diaminobiphenyl-3,3 ′, 5,5′-tetraol, 3,3′-diaminobiphenyl-4,4 ′, 5 5′-tetraol, 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane, 2,2′-bis (3-amino-2,4-dihydroxyphenyl) hexafluoropropane, 2,2 Examples include '-bis (4-amino-3,5-dihydroxyphenyl) hexafluoropropane. These diamines may be used alone or in combination of two or more.

  Among these diamines, (A-2) 3,3′-diaminobiphenyl-4,4′-diol, 2,2-bis (2, from the viewpoints of solubility of polyamide, insulation reliability, polymerization rate and availability 3-Amino-4-hydroxyphenyl) hexafluoropropane is preferred.

  From the viewpoint of flexibility, α, ω-bis (2-aminoethyl) polydimethylsiloxane, α, ω-bis (3-aminopropyl) polydimethylsiloxane, α, ω-bis (4-aminobutyl) poly Silicone diamines such as dimethylsiloxane, α, ω-bis (4-aminophenyl) polydimethylsiloxane, and α, ω-bis (3-aminopropyl) polydiphenylsiloxane can be used in combination. PAM-E, KF-8010, X-22-161A, X-22-1660B-3, etc. manufactured by Kogyo Co., Ltd. may be mentioned.

  Similarly, from the viewpoint of flexibility, polyoxyethylene diamine, polyoxypropylene diamine, polyoxytetramethylene diamine, and other polyoxyalkylene diamines (polyalkyl ether diamines) containing oxyalkylene groups having different numbers of carbon chains are combined. Can be used. Commercially available products include polyoxyethylene diamines such as Jeffermin ED-600, ED-900, ED-2003, EDR-148, and HK-511 manufactured by Huntsman, Inc., Jeffermin D-230, D-400, D- 2000, D-4000, polyoxypropylene diamines such as polyetheramine D-230, D-400, D-2000 manufactured by BASF Germany, and polyoxyls such as Jeffamine XTJ-542, XTJ-533, XTJ-536 Examples having a tetramethylene group include (A-2) Solvent solubility of the polyamide, and a polyoxytetramethylene group in that the melt viscosity at the time of thermosetting can be lowered and the resin flow can be promoted. Including Jeffamine XTJ-542, XTJ-533, XTJ-536 Arbitrariness.

  Further, as the diamine, other conventionally known diamines can be used within the range where the effects of the present embodiment are exhibited. Other diamines include, for example, 3,3′-diaminobenzophenone, 4,4′-diaminobenzophenone, 3,3′-diaminodiphenyl ether, 4,4′-diaminodiphenyl ether, 1,3-bis (3-aminophenoxy ) Benzene, 1,4-bis (4-aminophenoxy) benzene, bis (3- (3-aminophenoxy) phenyl) ether, bis (4- (4-aminophenoxy) phenyl) ether, 1,3-bis ( 3- (3-aminophenoxy) phenoxy) benzene, 1,4-bis (4- (4-aminophenoxy) phenoxy) benzene, bis (3- (3- (3-aminophenoxy) phenoxy) phenyl) ether, bis (4- (4- (4-Aminophenoxy) phenoxy) phenyl) ether, 1,3-bis (3- ( -(3-aminophenoxy) phenoxy) phenoxy) benzene, 1,4-bis (4- (4- (4-aminophenoxy) phenoxy) phenoxy) benzene, 4,4'-bis (3-aminophenoxy) biphenyl, 4,4′-bis (4-aminophenoxy) biphenyl, 2,2-bis [4- (3-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- (3-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoropropane, 2,2-bis [4- (4-aminophenoxy) phenyl]- 1,1,1,3,3,3-hexafluoropropane, m-phenylenediamine, o-phenylenediamine, p-phenylenediamine, bis (3-aminopheny ) Sulfide, bis (4-aminophenyl) sulfide, bis (3-aminophenyl) sulfoxide, bis (4-aminophenyl) sulfoxide, bis (3-aminophenyl) sulfone, bis (4-aminophenyl) sulfone, 2, Examples thereof include diamines such as 2-bis [4- (3-aminophenoxy) phenyl] butane.

  (A-2) The theoretical value of the phenolic hydroxyl value of the polyamide is preferably in the range of 20 to 100 mgKOH / g. When the theoretical value of the phenolic hydroxyl value is in the range of 20 to 100 mgKOH / g, the resin composition can be imparted with appropriate alkali processability, and the optimum time for alkali etching is reduced to a general DF peeling time. In this respect, more preferably in the range of 40-80 mg KOH / g.

  Although not particularly limited, the total molar ratio of dicarboxylic acid and diamine is preferably 0.3 or more, more preferably, because the molecular weight can be increased and the elongation and the like are excellent. It is 0.5 or more. On the other hand, from the viewpoint of controlling the amount of active dicarboxylic acid and improving storage stability, the total molar ratio of dicarboxylic acid and diamine is preferably 2.0 or less, and preferably 1.3 or less. Is more preferable. In addition, when acid chloride is used as a raw material, the total molar ratio of dicarboxylic acid and diamine is 1.0 or less in order to control the amount of chlorine remaining in the polymer skeleton and to use it suitably as an electronic material. Is preferred.

(A-3) Modified polyurethane (A-3) The modified polyurethane preferably has a phenolic hydroxyl group from the viewpoint of alkali solubility. Examples of the modified polyurethane (A-3) include a urea-modified polyurethane in which a diamine skeleton is introduced into a urethane bond through a urea bond. It doesn't matter.

  Urea-modified polyurethane is synthesized by reacting diisocyanate, diol and diamine.

  Specific examples of the diisocyanate compound include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, p-xylene diisocyanate, m-xylene diisocyanate, 4,4′-diphenylmethane diisocyanate (MDI), 1,5-naphthalene. Diisocyanate, 3,3′-dimethylbiphenyl-4,4′-diisocyanate, hexanemethylene diisocyanate, trimethylhexanemethylene diisocyanate, lysine diisocyanate, isophorone diisocyanate, 4,4′-methylenebis (cyclohexyl isocyanate), methyl cyclohexyl 2,4- (or 2,6) diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane and the like can be mentioned. These may be used alone or in combination.

  Further, from the viewpoint of flexibility, as diols, KF-6001, KF-6002, KF-6003, ethylene oxide adducts of bisphenol A, propylene oxide adducts of bisphenol A, bisphenol F Examples thereof include an ethylene oxide adduct, a propylene oxide adduct of bisphenol F, an ethylene oxide adduct of hydrogenated bisphenol A, and a propylene oxide adduct of hydrogenated bisphenol A.

  Specific examples of other diol compounds include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polyester polyol, polycarbonate diol, neopentyl glycol, 1,3. -Butylene glycol, 1,6-hexanediol, 2,2,4-trimethyl-1,3-pentanediol, 1,4-bis-β-hydroxyethoxycyclohexane, cyclohexanedimethanol, tricyclodecane dimethanol, water Bisphenol A, hydrogenated bisphenol F, hydroquinone dihydroxyethyl ether, p-xylene glycol, dihydroxyethyl sulfone, bis (2 Hydroxyethyl) -2,4-tolylene dicarbamate, 2,4-tolylene-bis- (2-hydroxyethyl) -m-xylene carbamate, bis (2-hydroxyethyl) isophthalate, and commercially available polycarbonate diol and polybutadiene diol And can be used in combination with the above highly flexible diol.

  Examples of the diamine containing a phenolic hydroxyl group include 2,4-diaminophenol, 2,5-diaminophenol, 2,6-diaminophenol, 3,5-diaminophenol, and 2,5-diaminobenzene-1. , 4-diol, 4,6-diaminobenzene-1,3-diol, 4,4′-diaminobiphenyl-3,3′-diol, 3,3′-diaminobiphenyl-4,4′-diol, 5, 5'-sulfonyl-bis (2-aminophenol), 4,4'-sulfonyl-bis (2-aminophenol), 5,5'-thio-bis (2-aminophenol), 4,4'-thio- Bis (2-aminophenol), 5,5′-oxy-bis (2-aminophenol), 4,4′-oxy-bis (2-aminophenol), 5,5′-methyl Bis (2-aminophenol), 4,4′-methylene-bis (2-aminophenol), 5,5 ′-(propane-2,2-diyl) -bis (2-aminophenol), 4, 4 '-(propane-2,2-diyl) -bis (2-aminophenol), 5,5'-phenylene-bis (2-aminophenol), and 4,4'-phenylene-bis (2-amino) Phenol) 2,2′-bis (3-amino-4-hydroxyphenyl) hexafluoropropane.

  Further, from the viewpoint of flexibility, the following diamine may be introduced through a urea bond.

  Examples of silicone diamines include α, ω-bis (2-aminoethyl) polydimethylsiloxane, α, ω-bis (3-aminopropyl) polydimethylsiloxane, α, ω-bis (4-aminobutyl) poly. Examples include dimethylsiloxane, α, ω-bis (4-aminophenyl) polydimethylsiloxane, and α, ω-bis (3-aminopropyl) polydiphenylsiloxane, and commercially available products such as PAM-E manufactured by Shin-Etsu Chemical Co., Ltd. , KF-8010, X-22-161A, X-22-1660B-3, and the like.

  Furthermore, as polyoxyalkylene diamines, polyoxyethylene diamines such as Jeffamine ED-600, ED-900, ED-2003, EDR-148, HK-511 manufactured by Huntsman, Inc., Jeffamine D-230, D -400, D-2000, D-4000, polyoxypropylene diamines such as polyetheramine D-230, D-400, D-2000 manufactured by BASF Germany, Jeffamine XTJ-542, XTJ-533, XTJ- Examples thereof include those having a polytetramethylene ethylene group such as 536.

  (A-3) It is preferable that the theoretical value of the phenolic hydroxyl value of the modified polyurethane is in the range of 20 to 100 mgKOH / g. When the theoretical value of the phenolic hydroxyl value is in the range of 20 to 100 mgKOH / g, the resin composition can be imparted with appropriate alkali processability, and the optimum time for alkali etching is reduced to a general DF peeling time. In this respect, more preferably in the range of 40-80 mg KOH / g.

  The modified polyurethane containing a phenolic hydroxyl group according to the present embodiment can be obtained by reacting a diisocyanate compound, a diamine compound, and a diol compound at a temperature of about 20 to 120 ° C. without solvent or in a solvent. In the case of using a diamine containing a functional hydroxyl group, a diisocyanate compound and a polyol compound are reacted in advance in a solvent-free or solvent at a temperature of about 20 to 120 ° C. to synthesize a prepolymer, and then a diamine compound containing a phenolic hydroxyl group And a method obtained by subjecting the chain extension reaction to a temperature of about 20 to 120 ° C. is preferable because the reaction can be easily controlled. The reaction is preferably performed in the presence of a urethanization catalyst.

  Although not particularly limited, since the molecular weight of the modified polyurethane can be increased and the elongation is excellent, the total molar ratio of diisocyanate, diol, and diamine is 0.3 to 2.0. Preferably, it is 0.5 to 1.3.

  The solvent used in the reaction in the solvent is not particularly limited, but nitrogen-containing solvents such as N, N-dimethylacetamide, N, N-diethylacetamide, N, N-dimethylformamide, N, N-diethyl Formamide, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, and N-methylcaprolactam, a sulfur-containing atomic solvent such as dimethyl sulfoxide, diethyl sulfoxide, dimethyl sulfone, diethyl sulfone, and Hexamethylsulfuramide, as well as oxygen-containing solvents such as phenolic solvents cresol, phenol, xylenol, diglyme solvents diethylene glycol dimethyl ether, ethylene glycol diethyl ether, carbitol Acetate, propylene glycol Ether ether, propylene glycol ethyl ether acetate, dipropylene glycol methyl ether acetate, diethylene glycol ethyl ether acetate, methyl methoxypropionate, ethyl methoxypropionate, methyl ethoxypropionate, ethyl ethoxypropionate, triethylene glycol dimethyl ether, tetra Examples include glyme, ketone solvents such as acetone, acetophenone, propiophenone, cyclohexanone and isophorone, ether solvents such as ethylene glycol, dioxane and tetrahydrofuran, and lactone solvents such as γ-butyrolactone. In particular, γ-butyrolactone, diethylene glycol ethyl ether acetate, triethylene glycol dimethyl ether and the like can be preferably used.

  The urethanization catalyst is not particularly limited as long as it is a compound that promotes the urethanation reaction. Specifically, for example, a tin-based catalyst such as dibutyltin dilaurate, dioctyltin dilaurate, stannous octoate, Ethylenediamine, triethylamine, N, N, N ′, N′-tetramethylpropylenediamine, N, N, N ′, N′-tetrakis (2-hydroxypropyl) ethylenediamine, N-methylmorpholine, 1,2-dimethylimidazole, 1,5-diaza-bicyclo (4,3,0) nonene-5, 1,8-diazabicyclo (5,4,0) -undecene-7 (hereinafter abbreviated as DBU), borane salts of these amine catalysts, Various amine salt catalysts such as DBU phenol salt, DBU octylate, DBU carbonate, naphthenic acid Neshiumu, lead naphthenate, carboxylates such as potassium acetate, triethyl phosphine, trialkylphosphine such as tribenzylphosphine, alkoxides of alkali metals such as sodium methoxide, and, zinc-based organometallic catalysts. An amine-based catalyst such as DBU is preferred from the viewpoint of the insulating properties of the cured product and the environmental load.

(B) Thermal crosslinking agent (B) There is no restriction | limiting in particular as a thermal crosslinking agent, if it has a crosslinkable functional group which reacts with the phenolic hydroxyl group in a resin composition. Examples of the compound having a crosslinkable functional group include (B-1) oxazoline compound, (B-2) benzoxazine compound, (B-3) isocyanate compound, methylol compound, acid anhydride compound, melamine resin, urea resin. And carbodiimide compounds, (B-1) oxazoline compounds, (B-2) benzoxazine compounds, and (B-3) isocyanate compounds are preferred from the viewpoints of availability, reactivity, storage stability, and the like. .

(B-1) Oxazoline Compound (B-1) An oxazoline compound is a compound having at least one oxazoline group in the molecule. (B-1) As an oxazoline compound, (A) 2 or more oxazoline groups in a molecule | numerator from a viewpoint which seals the hydroxyl group of alkali-soluble resin, and also forms bridge | crosslinking between (A) alkali-soluble resin. Those having the following are preferred.

  (B-1) Examples of the oxazoline compound include 1,3-bis (4,5-dihydro-2-oxazolyl) benzene (PBO), K-2010E, K-2020E, K-2030E manufactured by Nippon Shokubai Co., Ltd. 2,6-bis (4-isopropyl-2-oxazolin-2-yl) pyridine, 2,6-bis (4-phenyl-2-oxazolin-2-yl) pyridine, 2,2′-isopropylidenebis (4 -Phenyl-2-oxazoline), 2,2'-isopropylidenebis (4-tertiarybutyl-2-oxazoline) and the like. Also, 2-vinyl-2-oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, 2-isopropenyl-2-oxazoline, 2-isopropenyl-4- Mention may be made of copolymers of polymerizable monomers such as methyl-2-oxazoline. These oxazoline compounds may be used alone or in combination of two or more.

(B-2) Benzoxazine Compound (B-2) As the benzoxazine compound, a compound consisting only of a monomer may be used, or a compound in which several molecules are polymerized to form an oligomer. In addition, as the (B-2) benzoxazine compound, a plurality of benzoxazine compounds having different structures may be used in combination. (B-2) Examples of the benzoxazine compound include bisphenol benzoxazine. Commercially available products such as bisphenol F type benzoxazine (trade name: BF-BXZ), bisphenol S type benzoxazine (trade name: BS-BXZ), bisphenol A type benzoxazine (trade name: BA-BXZ) manufactured by Konishi Chemical Industries, Ltd. Product can be used.

(B-3) Isocyanate Compound (B-3) An isocyanate compound is a compound having at least one isocyanate group in the molecule. (B-3) As an isocyanate compound, from the viewpoint of (A) sealing the acidic functional group of the alkali-soluble resin and further forming a cross-link (A) with the alkali-soluble resin, two or more in the molecule. Those having an isocyanate group are preferable, for example, diphenylmethane-2,4′-diisocyanate; 3,2′-, 3,3′-, 4,2′-, 4,3′-, 5,2′-, 5 , 3'-, 6,2'- or 6,3'-dimethyldiphenylmethane-2,4'-diisocyanate;3,2'-,3,3'-,4,2'-,4,3'-,5,2'-,5,3'-,6,2'- or 6,3'-diethyldiphenylmethane-2,4'-diisocyanate;3,2'-,3,3'-,4,2'-4,3'-,5,2'-,5,3'-,6,2'- or 6,3'-dimethoxydiphenylmethane-2,4'-diisocyanate Diphenylmethane-4,4′-diisocyanate; diphenylmethane-3,3′-diisocyanate; diphenylmethane diisocyanate compounds such as diphenylmethane-3,4′-diisocyanate and hydrogenated products thereof; diphenyl ether-4,4′-diisocyanate; benzophenone -4,4'-diisocyanate;diphenylsulfone-4,4'-diisocyanate;tolylene-2,4-diisocyanate;tolylene-2,6-diisocyanate; 2,4-tolylene diisocyanate; 2,6-tolylene diisocyanate; aromatic aromatics such as m-xylylene diisocyanate; p-xylylene diisocyanate; 1,5-naphthalene diisocyanate; 4,4 ′-[2,2bis (4-phenoxyphenyl) propane] diisocyanate Socyanate compounds, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, transcyclohexane-1,4-diisocyanate, hydrogenated m-xylylene diisocyanate, and lysine diisocyanate Although aliphatic or alicyclic isocyanates such as can be used, aliphatic or alicyclic isocyanate compounds are preferred from the viewpoint of suppressing reactivity at low temperatures.

  The (B) thermal crosslinking agent is preferably contained in the resin composition in an amount of 3% by mass. By containing 3% by mass, the function as a plasticizer can reduce the melt viscosity of the thermosetting resin layer during the heating step and promote the resin flow during thermosetting. In this respect, the content of (B) the thermal crosslinking agent is more preferably 5% by mass or more.

  Further, the content of (B) the thermal crosslinking agent is more preferably 25% by mass or less. Since it is 25% by mass or less, the content of the low molecular weight substance derived from the remaining (B) thermal crosslinking agent can be suppressed when it becomes a resin cured product through the subsequent heating step. Insulation reliability is improved.

  (A) The phenolic hydroxyl group of the alkali-soluble resin and (B) the thermal cross-linking agent are inhibited from reacting in the low temperature region and react significantly in the high temperature region to form an appropriate three-dimensional cross-linked structure, Since there is no low molecular weight product by-produced, it is suitable for imparting fluidity of the resin in a low temperature region at the initial stage of thermosetting. Note that the laminate 11 according to the present embodiment is required to have a performance as an insulating film having alkali resistance and insulation reliability as the resin layer 14 is finally thermally cured. From this viewpoint, the ratio of the number of phenolic hydroxyl groups and the number of oxazoline groups in the resin composition is preferably in the range of hydroxyl group / oxazoline group = 4.0 to 0.1, and preferably 3.0 to 0.00. A range of 3 is more preferable. When the hydroxyl group / oxazoline group = 4 or less, the alkali resistance of the resin composition after thermosetting is improved, and when the hydroxyl group quantity / oxazoline group quantity = 0.3 or more, the resin composition after thermosetting is obtained. Flexibility and heat resistance are improved.

(C) Flame Retardant The resin composition according to the present embodiment can also be used by containing (C) a flame retardant from the viewpoint of improving flame retardancy. (C) Although there is no restriction | limiting in particular as a kind of flame retardant, A halogen-containing compound, a phosphorus-containing compound, an inorganic flame retardant, etc. are mentioned. These (C) flame retardants may be used alone or in admixture of two or more.

  (C) There is no restriction | limiting in particular as an addition amount of a flame retardant, According to the kind of (C) flame retardant to be used, it can change suitably. (C) The amount of the flame retardant added is generally preferably in the range of 5% by mass to 50% by mass based on the (A) alkali-soluble resin in the resin composition.

  Examples of the halogen-containing compound include organic compounds containing a chlorine atom or a bromine atom. Examples of the halogen-containing compound flame retardant include pentabromodiphenyl ether, octabromodiphenyl ether, decabromodiphenyl ether, tetrabromobisphenol A, hexabromocyclododecane tetrabromobisphenol A, and the like.

  Examples of the phosphorus-containing compound include phosphazene, phosphine, phosphine oxide, phosphate ester, and phosphite ester. In particular, from the viewpoint of compatibility with the resin composition, phosphazene, phosphite oxide, or phosphate ester is preferably used. As the phosphazene, for example, substituted hexa (phenoxy) cyclotriphosphazene having a cyano group or a hydroxyl group can be used.

  The addition amount of the phosphorus-containing flame retardant is desirably 40% by mass or less based on the (A) alkali-soluble resin in the resin composition. By being 40 mass% or less, the bleed-out resulting from the unreacted component after thermosetting can be suppressed, and high adhesiveness with the conductor 12a is obtained.

  Examples of inorganic flame retardants include antimony compounds and metal hydroxides. Examples of the antimony compound include antimony trioxide and antimony pentoxide. By using an antimony compound in combination with the above halogen-containing compound, antimony oxide pulls out halogen atoms from the flame retardant to produce antimony halide in the thermal decomposition temperature range of the plastic, thus synergistically increasing the flame retardancy. Can do. Examples of the metal hydroxide include aluminum hydroxide and magnesium hydroxide.

  Inorganic flame retardants do not dissolve in organic solvents. For this reason, as an inorganic flame retardant, it is preferable that the particle size of the powder is 100 micrometers or less. If the particle size of the powder is 100 μm or less, it is preferable that the powder is easily mixed into the resin composition and the transparency of the cured resin is not impaired. Furthermore, from the viewpoint of improving flame retardancy, the particle size of the powder is more preferably 50 μm or less, and even more preferably 10 μm or less.

  When forming a coating film, the viscosity and thixotropy are adjusted according to the coating method. If necessary, a filler or a thixotropic agent can be added and used. It is also possible to add additives such as known antifoaming agents, leveling agents and pigments.

(D) Plasticizer The resin composition according to the present embodiment contains (D) a plasticizer for the purpose of setting the minimum melt viscosity of the resin layer 14 at 150 to 200 ° C. to 700 Pa · s to 2300 Pa · s. Can be used.

  (D) Examples of the plasticizer include dimethyl phthalate, dibutyl phthalate, diisobutyl phthalate, diheptyl phthalate, dioctyl phthalate, dicyclohexyl phthalate, ditridecyl phthalate, butyl benzyl phthalate, diisodecyl phthalate, diphenyl phthalate, diallyl phthalate, octyl capryl phthalate Phthalic acid esters such as: triethylene glycol diacetate, tetraethylene glycol diacetate, dimethylglycol phthalate, ethyl phthalyl ethyl glycolate, methyl phthalyl ethyl glycolate, butyl phthalyl butyl glycolate, triethylene glycol dicabrylic acid Glycol esters such as esters; toluenesulfonamide, benzenesulfonamide, Amides such as n-butylbenzenesulfonamide and Nn-butylacetamide; aliphatic dibases such as diisobutyl adipate, dioctyl adipate, dimethyl sebacate, dibutyl sepacate, dioctyl sepacate, dioctyl azelate, dibutyl malate Acid esters; Triethyl citrate, tributyl citrate, glycerin triacetyl ester, butyl laurate, dioctyl 4,5-diepoxycyclohexane-1,2-dicarboxylate, and glycols such as polyethylene glycol and polypropylene glycol .

  (D) The plasticizer is a combination of at least two of the above plasticizers and is added in an amount such that the minimum melt viscosity of the resin layer 14 at 150 to 200 ° C. is 700 Pa · s to 2300 Pa · s. Although good, 50 mass% or less is preferable with respect to the resin composition whole component, and 40 mass% or less is more preferable. The compatibility of the resin and the (D) plasticizer varies depending on the structure, but by controlling the content of the (D) plasticizer to 50% by mass or less, bleed-out caused by unreacted components after thermosetting is suppressed. And high adhesion to the conductor 12a is obtained.

  Further, (C) the phosphoric acid ester, phosphazene and the like described above as a flame retardant can also be suitably used as a flame retardant and plasticizer because they also have an effect as a (D) plasticizer.

(G) Other additives The resin composition according to the present embodiment may be used by containing (G) other additives such as an antioxidant and an adhesion material within a range not impairing the effects of the present embodiment. it can.

  The antioxidant is used from the viewpoint of preventing oxidation of the resin composition. Examples of the antioxidant include bis [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionic acid] [ethylene bis (oxyethylene)] (trade name: Irganox (registered trademark) 245. (IRGANOX 245), manufactured by BASF) or the like can be used.

  Further, from the viewpoint of improving the adhesion between the resin layer 14 and the base material 12a, an adhesion material can be contained and used. Although it does not specifically limit as an adhesive material, A phenol compound, a nitrogen-containing organic compound, an acetylacetone metal complex etc. can be mentioned. Among these, a phenol compound is preferable.

<Multilayer printed wiring board>
As described above, the multilayer flexible wiring board 1 has been described as an example with reference to FIG. 1 and FIG. 2, but the laminate according to the present embodiment is not limited to the multilayer flexible wiring board application. It can be applied to all wiring boards.

  FIG. 3 is a schematic cross-sectional view showing each process of forming a via hole in the method for manufacturing a multilayer flexible wiring board according to the present embodiment. As shown in FIG. 3A, a resin layer 23a is provided on the surface of the substrate 12a of the double-sided flexible wiring board 10, and a substrate 22a is provided on the surface of the resin layer 23a. Here, the base material 12a is patterned as shown in FIG. 2C and functions as a wiring. As shown in FIG. 3B, a resist mask 101 using a dry film is formed on the surface of the base material 22a with respect to the laminate composed of the base material 12a / resin layer 23a / base material 22a. Next, the base material 22a exposed to the opening 101a formed in the resist mask 101 is removed by etching to form a conformal mask.

  Next, the resin layer 23a exposed to the opening 22a-1 of the conformal mask is removed by etching using an alkaline solution to form a via hole (blind via) 24 as shown in FIG. 3C. Etching using an alkaline solution can be performed, for example, by spraying a sodium hydroxide solution and then washing with water using a spray or acid washing with 1% hydrochloric acid or the like. Further, the resist mask 101 is peeled off during this etching.

  Next, as shown in FIG. 3D, an electroless copper plating process is performed on the surface of the base material 22a including the resin layer 23a forming the side wall surface of the via hole 24 and the surface of the base material 12a exposed to the via hole 24. The copper plating layer 102 is formed to obtain electrical continuity between the base material 12a and the base material 22a.

  Examples carried out to clarify the effects of the present invention will be described below. In addition, this invention is not limited at all by the following examples.

(Weight average molecular weight of alkali-soluble resin)
The weight average molecular weight was measured by gel permeation chromatography (GPC) under the following conditions. As the solvent, N, N-dimethylformamide (manufactured by Wako Pure Chemical Industries, Ltd., for high performance liquid chromatograph) was used, and 24.8 mmol / L lithium bromide monohydrate (manufactured by Wako Pure Chemical Industries, Ltd.) before the measurement. , Purity 99.5%) and 63.2 mmol / L phosphoric acid (manufactured by Wako Pure Chemical Industries, Ltd., for high performance liquid chromatograph) were used. A calibration curve for calculating the weight average molecular weight was prepared using standard polystyrene (manufactured by Tosoh Corporation).
Column: Shodex KD-806M (manufactured by Showa Denko KK)
Flow rate: 1.0 mL / min Column temperature: 40 ° C
Pump: PU-2080 Plus (manufactured by JASCO)
Detector: RI-2031Plus (RI: differential refractometer, manufactured by JASCO)
UV-2075 Plus (UV-VIS: UV-Visible Absorber, manufactured by JASCO)

(Melt viscosity of resin layer)
The resin composition solution was applied to a PET film (Unipeel (registered trademark) TR1, manufactured by Unitika) using a bar coater, and leveled at room temperature for 5 to 10 minutes. The PET film coated with this resin composition solution was heated in a hot air oven at 95 ° C. for 15 minutes, and then the PET film was peeled off to obtain a self-supporting film of 25 μm thick resin composition. A plurality of the self-supporting films were laminated and a sample having a thickness of 500 μm or more was prepared in advance by applying pressure at 0.3 MPa for 1 minute with a vacuum press machine (manufactured by Kitagawa Seiki Co., Ltd.).

  This sample was set in a viscoelasticity measuring device (rheometer) (DHR-2, manufactured by TA Instruments Inc.), measured at a frequency of 1 Hz, a load of 0.2 N, and a temperature rising rate of 5 ° C./min. The temperature was raised from 250C to 250 ° C. In the melt viscosity curve obtained by the measurement, the lowest melt viscosity (unit Pa · s) was defined as the lowest viscosity point, and the temperature (unit ° C.) at that point was read.

(Production of laminate)
The resin composition solution was applied to the mat surface of 12 μm thick electrolytic copper foil (F2-WS, manufactured by Furukawa Electric Co., Ltd.) using a bar coater, and leveled at room temperature for 5 to 10 minutes. The copper foil coated with this resin composition solution was heated in a hot air oven at 95 ° C. for 15 minutes, and further a vacuum dryer (DRR420DA, manufactured by ADVANTEC) and a belt-driven oil rotary vacuum pump (TSW-150, Sato Vacuum Co., Ltd.) was vacuum-dried at 90 ° C. for 30 minutes (under reduced pressure of about 6.7 × 10 ⁻² Pa) to obtain a laminate in which a resin layer having a thickness of 25 μm was laminated on the copper foil. . This laminate was used as a sample for evaluation of the following alkali dissolution rate and blind via hole shape.

(Evaluation of resin layer alkali dissolution rate)
The laminate described in the above section (Preparation of laminate) was sprayed with a 3 wt% aqueous sodium hydroxide solution heated to 45 ° C. at a pressure of 0.18 MPa, and it was required until the resin layer was completely removed. Time was taken as dissolution time. By dividing the film thickness (μm) of the resin layer before dissolution by the obtained dissolution time (seconds) and multiplying by 100, the alkali dissolution rate (μm / second) of the resin layer was calculated.

(Blind via hole formation method)
On one substrate of a double-sided flexible substrate (Espanex (registered trademark) M, manufactured by Nippon Steel Chemical Co., Ltd.) washed with a 3% hydrochloric acid aqueous solution, the resin layer of the laminate described in the section (Preparation of laminate) is provided. In a vacuum press machine (manufactured by Kitagawa Seiki Co., Ltd.), the laminate was pressed at 120 ° C. and 1.0 MPa for 2 minutes. Next, after laminating a dry film resist (Sunfort (registered trademark) AQ2578, manufactured by Asahi Kasei E-Materials Co., Ltd.) on the base material of the laminate, forming a circular hole pattern of 150 μmφ by exposure with a mask and further development, The substrate in the circular hole pattern was removed by etching with an aqueous ferric chloride solution.

  Thereafter, the resin is etched by spraying the resin layer with a 3% by mass sodium hydroxide aqueous solution heated to 45 ° C. at a pressure of 0.18 MPa for a predetermined time, and then with ion-exchanged water at 20 ° C. for 30 seconds, 20 ° C., Blind via holes were formed by spraying with 1% by mass hydrochloric acid for 15 seconds and with ion exchange water at 20 ° C. for 30 seconds.

(Blind via hole shape evaluation method)
The sample in which the blind via hole was formed was cured in a hot air oven at 180 ° C. for 1 hour. The blind via hole formed in this way is embedded in an epoxy resin, and after performing cross-sectional polishing processing to the center position of the blind via hole diameter using a polishing device (manufactured by Marumoto Stratos) perpendicular to the embedded wiring board, Observed with an optical microscope with a length measuring function, the values of the blind via hole parameters x and y in the formed via hole were measured.

  The shape of the blind via hole will be described. FIG. 4 is an explanatory diagram for explaining a method for determining the shape of a blind via hole in the embodiment of the present invention. As shown in FIG. 4, first, when a vertical cross section of the via hole 24 is observed, from the inner end face 105 of the opening 22a-1 of the base material 22a, the via hole 24 on the base material 22a side (upper side in FIG. 4). A horizontal distance to the end 106 is defined as a parameter x. Here, the parameter x is + when the end 106 of the via hole 24 is on the inner side than the end surface 105, and-when the end 106 is on the outer side.

  Further, the horizontal distance from the end face 105 inside the opening 22a-1 of the base 22a to the end 107 on the base 12a side (downward in FIG. 4) of the via hole 24 is defined as a parameter y. More specifically, the parameter y draws a perpendicular line A from the inner end face 105 of the opening 22a-1 of the base material 22a toward the base material 12a (in other words, toward the bottom of the via hole 24). It is a distance from the edge part 107 by the side of the base material 12a. Here, the parameter y is set to + when the end 107 of the via hole 24 is on the inner side than the perpendicular A, and is set to be on the outer side.

  When the cross-sectional observation of the blind via hole 10 holes is performed, the parameters x and y of the blind via hole shape described with reference to FIG. 4 are in the range of 0 ≧ x ≧ −5 μm and −5 μm ≦ y ≦ 5 μm. The case of 0 ≧ x ≧ −10 μm and −10 μm ≦ y ≦ 10 μm is indicated by ○, the case of 0 ≧ x ≧ −15 μm and −15 μm ≦ y ≦ 15 μm is indicated by Δ, and the other range is indicated. The case was marked with x.

[Synthesis Example of Polyimide A]
A three-necked separable flask was equipped with a nitrogen condenser, a thermometer, and a ball condenser equipped with a moisture separation trap. In oil bath room temperature, 92.0 g of γ-butyrolactone, 60.0 g of toluene, 2,2-bis ((4- (3,4-dicarboxyphenoxy) phenyl) propane dianhydride (trade names: BISDA-2000, SABIC Innovative Plastics Co., Ltd. (52.05 g) was stirred until uniform at 60 ° C. Further, polyalkyl ether diamine (trade name: Jeffamine (registered trademark) XTJ-542, Huntsman Co., Ltd.) 40.00 g was added little by little. After the addition, the temperature was raised to 180 ° C., and the mixture was heated and stirred for 3 hours.During the reaction, by-product water was azeotroped with toluene and dehydrated under reflux using a condenser tube with a water separation trap. After the reaction solution was once cooled to 35 ° C., 115.7 g of γ-butyrolactone, 2,2′-bis (3-amino-4-hydroxy) Nyl) hexafluoropropane (6FAP) (17.58 g) was added little by little, followed by heating and stirring for 3 hours at 70 ° C. After adding 2.24 g of aniline, the reaction solution was heated to 180 ° C. and refluxed for 3 hours. After removing the raw water, the reflux was stopped, all the toluene was removed, and the mixture was cooled to room temperature, and then the product was pressure filtered through a 5 μm filter to obtain a polyimide A varnish with a weight average molecular weight of 2. It was 0,000.

[Synthesis Example of Polyimide B]
A three-necked separable flask was equipped with a nitrogen condenser, a thermometer, and a ball condenser equipped with a moisture separation trap. At an oil bath room temperature, 81.0 g of γ-butyrolactone, 60.0 g of toluene, BISDA-2000; 39.04 g, and 7.76 g of ODPA were stirred at 60 ° C. until uniform. Furthermore, after adding XTJ-542; 42.00g little by little, it heated up to 180 degreeC and heat-stirred for 3 hours. During the reaction, by-product water was azeotroped with toluene and dehydrated under reflux using a ball-mounted condenser equipped with a water separation trap. The reaction solution was once cooled to 35 ° C., 120.6 g of γ-butyrolactone and 6FAP; 18.31 g were added little by little, and the mixture was heated and stirred at 70 ° C. for 3 hours. Further, after 1.49 g of aniline was added, the reaction solution was heated to 180 ° C. and refluxed for 3 hours. After draining by-product water, the reflux was stopped, toluene was completely drained, and the mixture was cooled to room temperature. Next, the product was subjected to pressure filtration with a 5 μm filter to obtain a polyimide B varnish. The weight average molecular weight was 27,000.

[Synthesis Example of Polyimide C]
A three-necked separable flask was equipped with a nitrogen condenser, a thermometer, and a ball condenser equipped with a moisture separation trap. At an oil bath room temperature, 79.5 g of N-methyl-2-pyrrolidone, 60.0 g of toluene, BISDA-2000; 49.45 g were stirred at 60 ° C. until uniform. Furthermore, after adding 30.10 g of polyalkyl ether diamine (Baxodur (registered trademark) EC302, manufactured by BASF) little by little, the temperature was raised to 180 ° C., and the mixture was heated and stirred for 3 hours. During the reaction, by-product water was azeotroped with toluene and dehydrated under reflux using a ball-mounted condenser equipped with a water separation trap. The reaction solution was once cooled to 35 ° C., 1.48 g of phthalic anhydride was added and stirred until uniform, and 91.3 g of N-methyl-2-pyrrolidone, 6FAP; 10.99 g were added little by little. After stirring with heating at 3 ° C. for 3 hours, the reaction solution was heated to 180 ° C. and refluxed for 3 hours. After draining by-product water, the reflux was stopped, toluene was completely drained, and the mixture was cooled to room temperature. Next, the product was pressure filtered through a 5 μm filter to obtain a polyimide C varnish. The weight average molecular weight was 54,000.

[Synthesis Example of Polyimide D]
A three-necked separable flask was equipped with a nitrogen condenser, a thermometer, and a ball condenser equipped with a moisture separation trap. N-methyl-2-pyrrolidone 80.5 g, toluene 60.0 g, BISDA-2000; 38.52 g, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (BPDA) 7 at oil bath room temperature .65 g was stirred at 60 ° C. until uniform. Furthermore, after adding XTJ-542; 42.00g little by little, it heated up to 180 degreeC and heat-stirred for 3 hours. During the reaction, by-product water was azeotroped with toluene and dehydrated under reflux using a ball-mounted condenser equipped with a water separation trap. After the reaction solution was once cooled to 35 ° C., 106.1 g of N-methyl-2-pyrrolidone and 10.81 g of 3,3′-diaminobiphenyl-4,4′-diol (HAB) were added little by little. And stirred for 3 hours. Further, after 1.49 g of aniline was added, the reaction solution was heated to 180 ° C. and refluxed for 3 hours. After draining by-product water, the reflux was stopped, toluene was completely drained, and the mixture was cooled to room temperature. Next, the product was pressure-filtered with a 5 μm filter to obtain a polyimide D varnish. The weight average molecular weight was 25,000.

[Synthesis Example of Polyimide E]
A three-necked separable flask was equipped with a nitrogen condenser, a thermometer, and a ball condenser equipped with a moisture separation trap. N-methyl-2-pyrrolidone 67.2g, toluene 60.0g, BISDA-2000; 30.19g, ODPA; 9.93g was stirred at 60 degreeC at the oil bath room temperature until it became uniform. Furthermore, 36.98 g of silicone diamine (KF-8010, manufactured by Shin-Etsu Chemical Co., Ltd.) was added little by little, and then the temperature was raised to 180 ° C. and stirred for 3 hours. During the reaction, by-product water was azeotroped with toluene and dehydrated under reflux using a ball-mounted condenser equipped with a water separation trap. The reaction solution was once cooled to 35 ° C., and 1.48 g of phthalic anhydride was added and stirred until uniform, then 120.3 g of N-methyl-2-pyrrolidone, 6FAP; 20.88 g were added little by little. After heating and stirring at 3 ° C. for 3 hours, the reaction solution was heated to 180 ° C. and refluxed for 3 hours. After draining by-product water, the reflux was stopped, toluene was completely drained, and the mixture was cooled to room temperature. Next, the product was pressure-filtered with a 5 μm filter to obtain a polyimide E varnish. The weight average molecular weight was 38,000.

[Synthesis example of polyimide F]
A three-necked separable flask was equipped with a nitrogen condenser, a thermometer, and a ball condenser equipped with a moisture separation trap. At an oil bath room temperature, 61.7 g of γ-butyrolactone, 60.0 g of toluene, BISDA-2000; 41.65 g, and 8.28 g of ODPA were stirred at 60 ° C. until uniform. Furthermore, after adding XTJ-542; 20.00g little by little, it heated up to 180 degreeC and heat-stirred for 3 hours. During the reaction, by-product water was azeotroped with toluene and dehydrated under reflux using a ball-mounted condenser equipped with a water separation trap. The reaction solution was once cooled to 35 ° C., 124.3 g of γ-butyrolactone, 6FAP; 28.63 g were added little by little, and the mixture was heated and stirred at 70 ° C. for 3 hours. Further, after 1.59 g of aniline was added, the reaction solution was heated to 180 ° C. and refluxed for 3 hours. After draining by-product water, the reflux was stopped, toluene was completely drained, and the mixture was cooled to room temperature. Next, the product was pressure-filtered with a 5 μm filter to obtain a polyimide F varnish. The weight average molecular weight was 31,000.

[Synthesis Example of Polyimide G]
A three-necked separable flask was equipped with a nitrogen condenser, a thermometer, and a ball condenser equipped with a moisture separation trap. At an oil bath room temperature, 72.7 g of γ-butyrolactone, 60.0 g of toluene, and 30.09 g of ODPA were stirred at 60 ° C. until uniform. Furthermore, after adding XTJ-542; 42.60g little by little, it heated up to 180 degreeC and heat-stirred for 3 hours. During the reaction, by-product water was azeotroped with toluene and dehydrated under reflux using a ball-mounted condenser equipped with a water separation trap. The reaction solution was once cooled to 35 ° C., 103.0 g of γ-butyrolactone and 6FAP; 21.02 g were added little by little, and the mixture was heated and stirred at 70 ° C. for 3 hours. Further, after adding 0.89 g of phthalic anhydride, the reaction solution was heated to 180 ° C. and refluxed for 3 hours. After draining by-product water, the reflux was stopped, toluene was completely drained, and the mixture was cooled to room temperature. Next, polyimide G varnish was obtained by carrying out pressure filtration of the product with a 5 micrometers filter. The weight average molecular weight was 48,000.

[Synthesis Example of Polyimide H]
A three-necked separable flask was equipped with a nitrogen condenser, a thermometer, and a ball condenser equipped with a moisture separation trap. At an oil bath room temperature, 96.7 g of γ-butyrolactone, 60.0 g of toluene, BISDA-2000; 41.65 g, and 8.28 g of ODPA were stirred at 60 ° C. until uniform. Furthermore, after adding XTJ-542; 55.00g little by little, it heated up to 180 degreeC and heat-stirred for 3 hours. During the reaction, by-product water was azeotroped with toluene and dehydrated under reflux using a ball-mounted condenser equipped with a water separation trap. The reaction solution was once cooled to 35 ° C., 130.5 g of γ-butyrolactone, 6FAP; 15.81 g were added little by little, and the mixture was heated and stirred at 70 ° C. for 3 hours. Further, after 1.59 g of aniline was added, the reaction solution was heated to 180 ° C. and refluxed for 3 hours. After draining by-product water, the reflux was stopped, toluene was completely drained, and the mixture was cooled to room temperature. Next, polyimide H varnish was obtained by carrying out pressure filtration of the product with a 5 micrometers filter. The weight average molecular weight was 37,000.

[Synthesis Example of Polyimide I]
A three-necked separable flask was equipped with a nitrogen condenser, a thermometer, and a ball condenser equipped with a moisture separation trap. At an oil bath room temperature, 111.7 g of γ-butyrolactone, 60.0 g of toluene, BISDA-2000; 41.65 g, and 8.28 g of ODPA were stirred at 60 ° C. until uniform. Furthermore, after adding XTJ-542; 70.00g little by little, it heated up to 180 degreeC and heat-stirred for 3 hours. During the reaction, by-product water was azeotroped with toluene and dehydrated under reflux using a ball-mounted condenser equipped with a water separation trap. The reaction solution was once cooled to 35 ° C., 133.2 g of γ-butyrolactone, 6FAP; 10.31 g were added little by little, and the mixture was heated and stirred at 70 ° C. for 3 hours. Further, after 1.59 g of aniline was added, the reaction solution was heated to 180 ° C. and refluxed for 3 hours. After draining by-product water, the reflux was stopped, toluene was completely drained, and the mixture was cooled to room temperature. Next, the product was subjected to pressure filtration with a 5 μm filter to obtain a polyimide I varnish. The weight average molecular weight was 37,000.

[Synthesis example of polyimide J]
A three-necked separable flask was equipped with a nitrogen condenser, a thermometer, and a ball condenser equipped with a moisture separation trap. At an oil bath room temperature, 69.1 g of γ-butyrolactone, 38.0 g of toluene, and 30.09 g of ODPA were stirred at 60 ° C. until uniform. Furthermore, after adding XTJ-542; 39.00g little by little, it heated up to 180 degreeC and heat-stirred for 3 hours. During the reaction, by-product water was azeotroped with toluene and dehydrated under reflux using a ball-mounted condenser equipped with a water separation trap. The reaction solution was once cooled to 35 ° C., 97.6 g of γ-butyrolactone, 6FAP; 19.78 g were added little by little, and the mixture was heated and stirred at 70 ° C. for 3 hours. Further, after adding 0.89 g of phthalic anhydride, the reaction solution was heated to 180 ° C. and refluxed for 3 hours. After draining by-product water, the reflux was stopped, toluene was completely drained, and the mixture was cooled to room temperature. Next, polyimide J varnish was obtained by carrying out pressure filtration of the product with a 5 micrometers filter. The weight average molecular weight was 20,000.

[Synthesis example of polyamide A]
A nitrogen inlet tube and a thermometer were attached to the three-necked separable flask. Under room temperature, 115.81 g of N-methyl-2-pyrrolidone, 6.21 g of 3,5-diaminophenol, XTJ-542; 23.00 g, KF-8010; 23.22 g were added and stirred until uniform. Further, a solution prepared by dissolving 19.69 g of terephthalic acid dichloride in 19.69 g of N-methyl-2-pyrrolidone in an ice bath at 0 to 5 ° C. was slowly added dropwise over 30 minutes and reacted at room temperature for 3 hours. To this solution, 0.84 g of benzoyl chloride was slowly added dropwise and stirred for 3 hours. After completion of the reaction, this solution was added to 1000 g of distilled water, and the precipitate was filtered off and dried under reduced pressure to obtain polyamide A powder. The weight average molecular weight was 29,000.

[Synthesis example of polyurethane A]
A nitrogen inlet tube and a thermometer were attached to the three-necked separable flask. In an oil bath at 90 ° C., 100.0 g of γ-butyrolactone and a diol of a propylene oxide adduct of bisphenol A (molecular weight 580, trade name: Adekapolyol (BPX-33), manufactured by Asahi Denka) are stirred until uniform. did. Further, 24.77 g of 4,4-diphenylmethane diisocyanate (MDI) was added and dissolved, and then stirred at 90 ° C. for 2 hours. 17.20 g of KF-8010; 17.20 g was added to this solution, reacted at 90 ° C. for 2 hours, and then cooled to 40 ° C. Further, 6FAP; 10.99 g and 52.2 g of γ-butyrolactone were added to this solution at 40 ° C. Stir for 10 hours. Next, the product was pressure filtered through a 5 μm filter to obtain a polyurethane A varnish. The weight average molecular weight was 30,000.

[Synthesis of Phosphazene Compound A]
The phosphazene compound A having a cyano group was synthesized by the method described in Synthesis Example 17 of JP-A No. 2002-114981.

  4-cyanophenol 1.32 mol (157.2 g), phenol 2.20 mol (124.2 g), hydroxylation in a 2 liter four-necked flask equipped with a stirrer, heating device, thermometer and dehydrator Sodium 2.64 mol (105.6 g) and 1000 ml toluene were added. This mixture was heated to reflux, water was removed from the system, and a toluene solution of cyanophenol and a sodium salt of phenol was prepared. 580 g of a 20% chlorobenzene solution containing 1 unit mol (115.9 g) of dichlorophosphazene oligomer was added dropwise to the toluene solution of cyanophenol and sodium salt of phenol at an internal temperature of 30 ° C. or lower while stirring. After the mixed solution was refluxed for 12 hours, a 5% aqueous sodium hydroxide solution was added to the reaction mixture and washed twice. Next, the organic layer was neutralized with dilute sulfuric acid, and then washed twice with water. The organic layer was filtered, concentrated, and dried in vacuo to obtain the desired product (phosphazene compound A).

[Synthesis of Phosphazene Compound B]
The phenoxyphosphazene compound B was synthesized by the method described in Synthesis Example 14 of JP-A-2002-114981.

99.5% phosphorus pentachloride (PCl ₅ ) 2512 g (12 mol), 99.5% ammonium chloride (NH ₄ Cl) 688 g (12.8 mol), 97.0% zinc chloride (ZnCl ₂ ) 20 g (0. 16 mol) and 5 liters of monochlorobenzene (MCB) are placed in a reaction kettle equipped with a temperature control device, a stirrer and a refluxing device. The reaction starts at 24 ° C., gradually warms up, and 3 hours after the reaction starts. The temperature was raised to 130 ° C. Furthermore, after refluxing with stirring at 130 ° C. to 134 ° C. for 2 hours, the reaction mixture was filtered to remove 76 g of a white filtration residue to obtain chlorophosphazene as an almost colorless and transparent MCB solution. This solution was concentrated to give a 39.5% chlorophosphazene solution.

Next, 2931 g (31.14 mol) of phenol (PhOH), 596.67 g (25.95 mol) of metal Na and 7 liters of tetrahydrofuran (THF) were placed in a reaction kettle equipped with a temperature controller, a stirrer and a reflux device. The mixture was refluxed for 8 hours with stirring. Next, a solution obtained by dissolving the previously obtained 39.5% chlorophosphazene solution (3172.41 g) in 5.5 liters of THF was added dropwise to the solution at a temperature of 42 ° C to 79 ° C. After completion of the dropwise addition, refluxing was continued for 10 hours at 78 ° C. with stirring. The reaction mixture was then concentrated and dissolved in 8 liters of monochlorobenzene, 5 liters of water and 3 liters of 5% aqueous NaOH. This was washed in the following order. Washed twice with 7 liters of 5% aqueous NaOH solution, once with 7 liters of 5% hydrochloric acid, once with 7 liters of 7% aqueous NaHCO ₃ solution, twice with 7 liters of water, dried by adding MgSO ₄ and concentrated. . Finally, it was vacuum-dried at 80 ° C. and 3 torr or less for 12 hours to obtain the desired product (phosphazene compound B).

[Example 1]
The solid content of polyimide A is 52.9% by mass, 1,3-bis (4,5-dihydro-2-oxazolyl) benzene (PBO), which is an oxazoline compound as a thermal crosslinking agent, is 5.1% by mass, an antioxidant. Irganox 245 (IRG245, manufactured by BASF) is 2.0 mass%, and composite magnesium hydroxide (trade name: MGZ-5R, manufactured by Sakai Chemical Industry Co., Ltd.) is 37.0 mass% as a flame retardant. A resin composition was prepared so that the phosphazene compound A, which is a flame retardant, was 3.0% by mass, and diluted with γ-butyrolactone so that the total solid content of the resin composition was 43% by mass. A laminate was produced using this resin composition solution, and the melt viscosity was measured with a rheometer using the produced laminate, and the alkali dissolution rate and the blind via hole shape were evaluated. Table 1 below shows the evaluation results of the lowest melt viscosity, the temperature at the lowest melt viscosity, the alkali dissolution rate, and the blind via hole shape.

[Examples 2 to 14]
A resin composition was prepared in the same manner as in Example 1 to produce a laminate, and the produced laminate was evaluated. For polyimides C, D, E, and polyamide A synthesized with N-methyl-2-pyrrolidone as the solvent, N-methyl-2-pyrrolidone was used instead of γ-butyrolactone. For Example 3, phosphazene compound B, which is a flame retardant having plasticity, was used. In Example 7, a benzoxazine compound (trade name: BS-BXZ, manufactured by Konishi Chemical Co., Ltd.) is used as a thermal crosslinking agent. In Example 8, an isocyanate compound (trade name: SBN-70D, manufactured by Asahi Kasei Chemicals) is used. Was used. Table 1 below shows the evaluation results of the resin compositions of Examples 2 to 14, the lowest melt viscosity, the temperature at the lowest melt viscosity, the alkali dissolution rate, and the blind via hole shape.

[Comparative Examples 1-6]
The resin composition was prepared similarly to Examples 1-14, the laminated body was produced, and the produced laminated body was evaluated. In Comparative Example 2, a trifunctional epoxy compound (trade name: VG3101, manufactured by Printec Co., Ltd.) was used as a thermal crosslinking agent. The composition of the resin compositions of Comparative Examples 1 to 6, the lowest melt viscosity, the temperature at the lowest melt viscosity, the alkali dissolution rate, and the evaluation results of the blind via hole shape are shown in Table 1 below.

  As shown in Table 1, by using a laminate in which the minimum melt viscosity of the resin layer is 700 Pa · s or more and 2300 Pa · s or less and the temperature range indicating the minimum melt viscosity is 150 ° C. or more and 200 ° C. or less, It was confirmed that the via hole shape was good (Examples 1 to 14). In particular, for a laminate having a minimum melt viscosity of 800 Pa · s or more and 2000 Pa · s or less, the fluidity of the resin during the heating step was appropriately imparted, and the amount of overetching was small (Examples 1 to 3 and Examples). 5-9). In particular, a laminate having a minimum melt viscosity of 1500 Pa · s to 1700 Pa · s and an alkali dissolution rate of 0.15 μm / second to 0.25 μm / second obtained a very good blind via hole shape. (Examples 1, 2, 5, 6).

  From these results, it can be seen that the resin compositions according to Examples 1 to 14 can be suitably used for forming a via hole in an interlayer insulating film using alkali etching.

  On the other hand, a laminate having a minimum melt viscosity exceeding 2300 Pa · s could not provide sufficient resin fluidity at the time of thermosetting, and a good blind via hole shape could not be obtained (Comparative Examples 1 and 3). In addition, it was difficult to form a via hole by alkali etching in a laminate having a minimum melt viscosity of less than 120 ° C., and a favorable blind via hole shape could not be obtained (Comparative Example 2). This is presumed to be caused by the progress of crosslinking between the acidic functional group of the alkali-soluble resin and the curing agent in the solvent drying step at a low temperature during the production of the laminate. Further, in the laminate having a minimum melt viscosity of less than 700 Pa · s, the resin flowed excessively during thermosetting, and a good blind via hole shape was not obtained (Comparative Examples 4, 5, and 6).

  From these results, the laminates of Comparative Examples 1 to 6 are not suitable for the fluidity of the resin at the time of thermosetting and / or the alkali dissolution rate is not sufficient, so that via holes are formed in the interlayer insulating film using alkali etching. It proves difficult to use as such.

  The present invention is not limited to the embodiment described above, and can be implemented with various modifications. For example, the material, arrangement, shape, and the like of the members in the above embodiment are illustrative, and can be appropriately changed and implemented within a range where the effects of the present invention are exhibited. In addition, various modifications can be made without departing from the scope of the present invention.

  In particular, the present invention can be suitably used as a laminate used for an interlayer insulating film and a printed wiring board substrate.

DESCRIPTION OF SYMBOLS 1 Multilayer flexible wiring board 10 Double-sided flexible wiring board 11, 13, 21a, 21b Laminate body 12a, 12b, 22a, 22b Base material 14, 23a, 23b Resin layer 16 Resin hardened material layer

Claims (11)

Comprising a base material that is a conductor, and a thermosetting resin layer provided on the base material,
The thermosetting resin layer is
Containing an alkali-soluble resin,
The minimum melt viscosity is 700 Pa · s or more and 2300 Pa · s or less, and
The temperature range which shows the said minimum melt viscosity is 150 to 200 degreeC, The laminated body characterized by the above-mentioned.   The laminate according to claim 1, wherein the thermosetting resin layer has a melt viscosity at 40 ° C. of 10,000 Pa · s or more.   The dissolution rate of the thermosetting resin layer in a 3 mass% sodium hydroxide aqueous solution at 45 ° C is 0.15 µm / sec or more and 0.50 µm / sec or less. The laminated body as described in.   The laminate according to claim 3, wherein the minimum melt viscosity is 1500 Pa · S or more and 1700 Pa · s or less, and the dissolution rate is 0.15 µm / sec or more and 0.25 µm / sec or less.   The laminate according to any one of claims 1 to 4, wherein the alkali-soluble resin is a polyimide having a phenolic hydroxyl group. The laminate according to claim 5, wherein the phenolic hydroxyl group has a structure represented by the following general formula (1).

(In General Formula (1), X represents a single bond or —C (—CF ₃ ) ₂ —, and k represents an integer of 1 to 4.) The laminate according to claim 5 or 6, wherein the polyimide has a structure represented by the following general formula (2).

(In general formula (2), R represents a divalent organic group.)   The laminate according to any one of claims 1 to 7, wherein the thermosetting resin layer contains an oxazoline compound.   The laminate according to any one of claims 1 to 8, wherein the substrate is a copper foil. A step of stacking the thermosetting resin layer side of the laminate according to any one of claims 1 to 9 on a substrate having wiring;
Forming a resist mask made of a dry film resist on the substrate side of the laminate; and
Removing a portion of the substrate by etching using the resist mask to form a conformal mask; and
Removing a part of the thermosetting resin layer with an alkaline solution through the conformal mask to form a via hole, removing the resist mask, and then performing acid cleaning;
A step of thermosetting the thermosetting resin layer to form a cured resin layer;
A method for producing a multilayer printed wiring board, comprising:   A multilayer printed wiring board manufactured by the manufacturing method according to claim 10.

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