JP6445903B2 - LAMINATED FILM AND METHOD FOR PRODUCING LAMINATED STRUCTURE - Google Patents

Description

  The present invention relates to a laminated film including an insulating film, and relates to a laminated film that can be used for forming an insulating layer in, for example, a printed wiring board. Moreover, this invention relates to the manufacturing method of the laminated structure using the said laminated | multilayer film.

  Conventionally, various resin compositions have been used to obtain electronic components such as laminates and printed wiring boards. For example, in a multilayer printed wiring board, a resin composition is used in order to form an insulating layer for insulating inner layers or to form an insulating layer located in a surface layer portion. On the surface of the insulating layer, wiring that is generally a metal part is laminated.

  Moreover, in order to form an insulating layer, the insulating film which made the said resin composition into a film may be used. This insulating film may be used in the form of a laminated film laminated on a base film in order to improve the handleability.

  For example, in a laminated film including an interlayer insulating film for a printed wiring board, an insulating film formed of an epoxy resin composition is laminated on a first base film, and a second base film is formed on the insulating film. It is formed by stacking. When forming an insulating layer in a printed wiring board, one base film is peeled from the insulating film. From the surface side where the insulating film is exposed, it is laminated on a lamination target member such as an inner circuit board by a vacuum laminator or a press. Then, the other base film is peeled off. Then, a printed wiring board is manufactured by forming a metal wiring or curing an insulating film.

  The above laminated films are disclosed, for example, in Patent Documents 1 and 2 below.

  Patent Document 1 below discloses a laminated film obtained by coating an epoxy resin composition on a support film and then overlaying a release film on the epoxy resin composition. The epoxy resin composition includes a biphenyl type epoxy resin (A) having an average epoxy equivalent of less than 450, a bisphenol A type epoxy resin (B) having an average epoxy equivalent of 450 or more, and a phenolic novolac resin having a triazine ring. (C). In the said epoxy resin composition, the mass ratio of the said bisphenol A type epoxy resin (B) with respect to the said biphenyl type epoxy resin (A) is 0.25-2. At the time of use of the laminated film, the support film is peeled after the epoxy resin composition is brought into a semi-cured state.

  Patent Document 2 listed below discloses a printed wiring board interlayer insulating film (laminated film) comprising a supporting base film, and an insulating resin layer and a protective film which are laminated on the surface of the supporting base film at room temperature. ing. In this laminated film, the support base film is provided so as to be peelable at the time of lamination.

JP 2009-29930 A JP 2002-252470 A

  In the conventional laminated films as described in Patent Documents 1 and 2, it may be difficult to peel the substrate film from the surface of the insulating film after the lamination process. For example, streaks may be formed on the surface of the insulating film when the base film is peeled off. As a result, when a metal layer is formed on the surface of the insulating layer formed of the insulating film, the adhesion strength between the insulation layer and the metal layer may be lowered, or unevenness in the adhesion strength depending on the location may occur.

  Also, in order to increase the peelability of the base film, just using a base film with high releasability, coating defects such as repellency are likely to occur when an insulating film is formed on the surface of the base film. Become. On the other hand, if the surface of the insulating layer after peeling is in a sticky state, suspended matters in the environment may easily adhere to the surface as contaminants. As a countermeasure, if the base film is peeled off after the insulating film is in a semi-cured state as described in Patent Document 1, volatile components such as a solvent easily remain in the insulating layer. As a result, reliability such as insulation is reduced. Further, when the base film is peeled after the insulating film is in a semi-cured state, the surface shape of the base film is easily transferred to the insulating layer, and it is difficult to form fine metal wiring.

  An object of the present invention is to provide a laminated film capable of satisfactorily peeling the base film after laminating the insulating film together with the base film, and a method for producing a laminated structure using the laminated film. That is.

  A limited object of the present invention is to provide a laminated film capable of increasing the adhesive strength between the insulating layer and the metal layer cured from the insulating film, and to provide a method for producing a laminated structure using the laminated film. That is.

  According to a wide aspect of the present invention, an insulating film and a first base film laminated on the first surface of the insulating film are provided, and a first side opposite to the first surface of the insulating film is provided. Or the second base film laminated on the surface of 2, the insulating film includes a thermosetting resin, a curing agent, a filler, and a solvent, and the second of the insulating film The proportion of the solvent in the region up to a depth of 3 μm on the surface side is greater than the proportion of the solvent in the region up to a depth of 3 μm on the first surface side of the insulating film. When the first base film is laminated on the lamination target member and used from the surface side of 2, and the laminated film includes the second base film, the insulating film The second A laminated film is provided in which the second base film is peeled off from the second surface of the insulating film before being laminated on the lamination target member from the surface side.

  In a specific aspect of the laminated film according to the present invention, the depth of the first surface side of the insulating film in the proportion of the solvent in the region up to a depth of 3 μm on the second surface side of the insulating film. The ratio of the solvent in the region up to 3 μm is 2 or more and 10 or less.

  In a specific aspect of the laminated film according to the present invention, the proportion of the filler in the region up to a depth of 3 μm on the second surface side of the insulating film is a depth on the first surface side of the insulating film. More than the abundance of the filler in the region up to 3 μm.

  In a specific aspect of the laminated film according to the present invention, the depth of the filler on the first surface side of the insulating film in the region up to 3 μm in depth on the second surface side of the insulating film. More preferably, the ratio of the filler to the existing ratio in the region up to 3 μm is 1.5 or more and 4.0 or less.

  In a specific aspect of the laminated film according to the present invention, the peel strength of the second base film with respect to the insulating film is lower than the peel strength of the first base film with respect to the insulating film.

  On the specific situation with the laminated film which concerns on this invention, the peeling strength of the said 1st base film with respect to the said insulating film is 5 mN / cm or more and 30 mN / cm or less.

  According to a wide aspect of the present invention, when the laminated film includes the second base film using the above-described laminated film, the second base material from the second surface of the insulating film. A laminate step of peeling the film and laminating the insulating film from the second surface side in a state where the first base film is laminated, and a laminate target member, and after the laminating step, the insulating film And a peeling step of peeling the first base film from the first surface of the laminated structure.

  In a specific aspect of the method for manufacturing a laminated structure according to the present invention, the method for manufacturing the laminated structure includes: a precuring step for precuring the insulating film after the peeling step; and a step after the precuring step. A roughening treatment step for roughening a surface opposite to the lamination target member side of the insulating film, and a surface opposite to the lamination target member side of the roughened insulation film after the roughening treatment step. And a plating step of forming a metal layer by plating, and a main curing step of curing the precured insulating film after the plating step.

  The laminated film according to the present invention includes an insulating film and a first base film laminated on the first surface of the insulating film. The laminated film according to the present invention includes or does not include the second base film laminated on the second surface opposite to the first surface of the insulating film. In the laminated film according to the present invention, the insulating film contains a thermosetting resin, a curing agent, a filler, and a solvent, and the presence of the solvent in a region up to a depth of 3 μm on the second surface side of the insulating film. Since the ratio is higher than the ratio of the solvent in the region up to the depth of 3 μm on the first surface side of the insulating film, the insulating film is moved from the second surface side to the first base film. By laminating and using on the member to be laminated in a state where is laminated, the first base film can be favorably peeled after laminating the insulating film together with the first base film.

FIG. 1 is a cross-sectional view schematically showing a laminated film according to an embodiment of the present invention. 2A to 2D are schematic cross-sectional views for explaining each step of manufacturing a laminated structure using the laminated film according to one embodiment of the present invention. FIGS. 3A to 3C are schematic cross-sectional views for explaining each step of manufacturing a laminated structure using the laminated film according to one embodiment of the present invention.

  Details of the present invention will be described below.

(Laminated film)
Hereinafter, the present invention will be clarified by describing specific embodiments of the present invention with reference to the drawings.

  FIG. 1 is a cross-sectional view schematically showing a laminated film according to an embodiment of the present invention.

  The laminated film 1 includes an insulating film 2, a first base film 3, and a second base film 4. The first base film 3 is laminated on the first surface 2 a of the insulating film 2. The second base film 4 is laminated on the second surface 2 b opposite to the first surface 2 a of the insulating film 2.

  In this invention, it is preferable that a laminated | multilayer film is equipped with the 2nd base film laminated | stacked on the 2nd surface of the insulating film. However, the laminated film may not include the second base film laminated on the second surface of the insulating film. The laminated film includes or does not include the second base film laminated on the second surface of the insulating film.

  The insulating film 2 includes a thermosetting resin, a curing agent, a filler, and a solvent. In the laminated film 1, the solvent existing ratio X2 in the region up to 3 μm deep on the second surface 2 b side of the insulating film 2 is the solvent content in the region up to 3 μm deep on the first surface 2 a side of the insulating film 2. More than the existing ratio X1. Therefore, the solvent is unevenly distributed in the insulating film 2. The insulating film 2 has a solvent concentration distribution.

  In the laminated film 1, the insulating film 2 is used by laminating on the member to be laminated in the state where the first base film 3 is laminated from the second surface 2 b side. Before the insulating film 2 is laminated on the lamination target member from the second surface 2b side, the second base film 4 is peeled off from the second surface 2b of the insulating film 2.

  In the present invention, in the case where the laminated film includes the second base film, the second from the second surface of the insulating film before the insulating film is laminated to the lamination target member from the second surface side. The base film is peeled off.

  In this embodiment, since the above-described configuration is provided, and in the present invention, since the above-described configuration is provided, the first base film is good after laminating the insulating film together with the first base film. Can be peeled off. The first base film can be easily peeled off, and the formation of streaks during peeling can be suppressed. Furthermore, it becomes difficult for foreign matter to adhere to the surface of the insulating film after peeling. Furthermore, after the first substrate film is peeled off, the exposed surface of the insulating film has a good shape without peeling stripes. For this reason, the adhesive strength of the insulating layer and metal layer which the insulating film hardened | cured can be improved by arrange | positioning a metal layer on the surface of this insulating film.

  Furthermore, even if the metal wiring formed on the insulating layer is miniaturized, the metal wiring can be satisfactorily formed.

  Examples of the method of unevenly distributing the solvent in the insulating film include, for example, preparing films in different dry states, a method of stacking a plurality of films, a method of controlling a drying rate using a plurality of solvents having different boiling points, and And a method for controlling the volatilization rate of the solvent by changing the thickness of the film.

  The region up to a depth of 3 μm on the second surface side of the insulating film is a region having a thickness of 3 μm from the second surface toward the inside in the thickness direction of the insulating film. The region up to a depth of 3 μm on the first surface side of the insulating film is a region having a thickness of 3 μm from the first surface toward the inside in the thickness direction of the insulating film.

  The solvent existing ratio X2 in the region up to a depth of 3 μm on the second surface side of the insulating film is the average of the solvent in the entire region up to a depth of 3 μm on the second surface side of the insulating film. It is an existing ratio. The solvent existing ratio X1 in the region up to a depth of 3 μm on the first surface side of the insulating film is the average of the solvent in the entire region up to a depth of 3 μm on the first surface side of the insulating film. It is an existing ratio.

  From the viewpoint of further exfoliating the first substrate film and further increasing the adhesion strength between the insulating layer and the metal layer, the ratio of the solvent existing ratio X2 to the solvent existing ratio X1 (X2 / X1) is preferably 2 or more, more preferably 4 or more. The ratio (X2 / X1) is preferably 10 or less. If the ratio (X2 / X1) is less than or equal to the above upper limit, the amount of solvent increases on the first base film side, and the first base film is laminated after being laminated on a member to be laminated such as a copper clad laminate. The first base film is difficult to peel off unintentionally before peeling. When the ratio (X2 / X1) is equal to or greater than the above lower limit, the amount of solvent becomes appropriate on the second base film side, and tackiness is lowered. Therefore, the laminate is laminated on a member to be laminated such as a copper-clad laminate. When it does, a void becomes difficult to produce between a lamination | stacking object member and an insulating film, and it becomes difficult to generate | occur | produce a wrinkle in an insulating film.

  From the viewpoint of further exfoliating the first base film and further enhancing the adhesion strength between the insulating layer and the metal layer, the above-mentioned region in the region up to a depth of 3 μm on the second surface side of the insulating film. The filler existing ratio Y2 is preferably larger than the filler existing ratio Y1 in the region up to a depth of 3 μm on the first surface side of the insulating film. From the viewpoint of further exfoliating the first base film and further enhancing the adhesion strength between the insulating layer and the metal layer, the above-mentioned region in the region up to a depth of 3 μm on the second surface side of the insulating film. The ratio (Y2 / Y1) of the filler existing ratio Y2 to the filler existing ratio Y1 in the region up to a depth of 3 μm on the first surface side of the insulating film is preferably 1.5 or more, more preferably 2.5 or more. The ratio (Y2 / Y1) is preferably 4.0 or less. In the insulating film, it is preferable that the filler is unevenly distributed. The insulating film preferably has a filler concentration distribution.

  In the insulating film, as a method of unevenly distributing the filler, for example, in the step of forming a resin varnish into a film (drying step), the filler is continuously or stepwise from the surface side by utilizing the specific gravity difference between the filler and the other resin. And a method in which films having different filler contents are prepared in advance and a plurality of films are stacked.

  From the viewpoint of easily forming an insulating film, peeling the first base film better, and further increasing the adhesion strength between the insulating layer and the metal layer, the second base film with respect to the insulating film Is preferably lower than the peel strength of the first base film with respect to the insulating film, more preferably 30 mN / cm or more. The absolute value of the difference between the peel strength of the second base film with respect to the insulating film and the peel strength of the first base film with respect to the insulating film is preferably 20 mN / cm or less. The peel strength of the first base film with respect to the insulating film is preferably 5 mN / cm or more, and preferably 30 mN / cm or less.

  From the viewpoint of further peeling off the first base film and further increasing the adhesion strength between the insulating layer and the metal layer, the peel strength of the first base film with respect to the insulating film after the laminating step is Preferably it is 10 mN / cm or more, More preferably, it is 20 mN / cm or more, Preferably it is 60 mN / cm or less, More preferably, it is 40 mN / cm or less. When the peel strength is equal to or higher than the lower limit, unintended peeling of the first base film is suppressed. A 1st base film can be favorably peeled as the said peeling strength is below the said upper limit.

  Examples of the first and second base films include polyester resin films such as polyethylene terephthalate film and polybutylene terephthalate film, olefin resin films such as polyethylene film and polypropylene film, and polyimide resin films. In order to control the presence ratio of the solvent, it is preferable that the first base film and the second base film are different.

  Each component that can be used for the insulating film will be described in detail later.

(Manufacturing method of laminated structure)
In the manufacturing method of the laminated structure according to the present invention, the above-described laminated film is used. When the laminated film includes the second base film, the second base film is peeled from the second surface of the insulating film, and the laminated film is used. The method for manufacturing a laminated structure according to the present invention includes a laminating step and a peeling step. The laminating step is a step of laminating the insulating film from the second surface side on the lamination target member in a state where the first base film is laminated. The peeling step is performed after the laminating step. The peeling step is a step of peeling the first base film from the first surface of the insulating film.

  In the manufacturing method of the laminated structure which concerns on this invention, since the structure mentioned above is provided, after laminating | stacking an insulating film with a 1st base film, a 1st base film can be peeled favorably. The first base film can be easily peeled off, and the formation of streaks during peeling can be suppressed. Furthermore, after the first base film is peeled off, the exposed surface of the insulating film has a good shape. For this reason, the adhesive strength of the insulating layer and metal layer which the insulating film hardened | cured can be improved by arrange | positioning a metal layer on the surface of this insulating film.

  Examples of the member to be laminated include a substrate having a metal layer on the surface and an insulating layer having a metal layer on the surface. The lamination target member may be a substrate having a metal layer on the surface or an insulating layer having a metal layer on the surface. The substrate having the metal layer on the surface is preferably a circuit board.

  The manufacturing method of the laminated structure according to the present invention includes: 1) a pre-curing step for pre-curing the insulating film after the peeling step, and 2) after the pre-curing step, opposite to the lamination target member side of the insulating film. 3) Roughening treatment step for roughening the surface of the film 3) Plating for forming a metal layer by plating treatment on the surface opposite to the lamination target member side of the roughened insulating film after the roughening treatment step It is preferable to provide each process of the process and 4) the main hardening process of hardening the precured insulating film after the said plating process.

  Next, each process of the manufacturing method of a laminated structure is demonstrated concretely, referring FIG. 2 (a)-(d) and FIG. 3 (a)-(c).

  First, the laminated film 1 shown in FIG. 1 is prepared. Using this laminated film 1, the second base film 4 is peeled from the second surface 2 b of the insulating film 2. After peeling of the second base film 4, a laminated film 1A of the insulating film 2 and the first base film 3 is obtained (FIG. 2 (a), pre-peeling step (first peeling step)).

  Next, the insulating film 2 is laminated on the lamination target member 21 in a state where the first base film 3 is laminated from the second surface 2b side (FIG. 2B, laminating step). Here, a substrate having a metal layer 21b on the surface is used as the lamination target member 21, and this substrate is a circuit board. This substrate has a substrate body 21a and a metal layer 21b on the substrate body 21a. After lamination, the insulating film 2 is in contact with the lamination target member 21 on the second surface 2b side. The insulating film 2 is in contact with the substrate body 21a in a region where the metal layer 21b is not present, and is in contact with the metal layer 21b in a region where the metal layer 21b is present.

  Next, the 1st base film 3 is peeled from the 1st surface 2a of the insulating film 2 after the said lamination process. When the 1st base film 3 is peeled, the 1st surface 2a of the insulating film 2 will be exposed (FIG.2 (c), peeling process (2nd peeling process)). This peeling step is preferably performed before the pre-curing step described later. If the peeling step is performed before the pre-curing step, volatile components such as a solvent hardly remain in the insulating layer. As a result, a decrease in reliability such as insulation can be suppressed. Further, after the first base film is peeled off, the surface shape of the first base film is hardly transferred to the insulating layer.

  Next, after the peeling step, the insulating film 2 is precured. The insulating film 2 becomes a precured insulating film 2A (FIG. 2 (d), precuring step).

  The pre-curing temperature for appropriately pre-curing the insulating film is preferably 100 ° C. or more, preferably 200 ° C. or less, and the pre-curing time is preferably 0.5 hours or more, preferably 2 hours or less.

  Next, after the preliminary curing step, the first surface 2a (upper surface) opposite to the lamination target member 21 side of the insulating film 2 is roughened. The pre-cured insulating film 2A becomes a roughened insulating film 2B (FIG. 3A, roughening treatment step). You may perform a swelling process before a roughening process.

  For the roughening treatment, for example, a chemical oxidizing agent such as a manganese compound, a chromium compound, or a persulfuric acid compound is used. These chemical oxidizers are used as an aqueous solution or an organic solvent dispersion after water or an organic solvent is added. The roughening liquid used for the roughening treatment generally contains an alkali as a pH adjuster or the like. The roughening solution preferably contains sodium hydroxide.

  Examples of the manganese compound include potassium permanganate and sodium permanganate. Examples of the chromium compound include potassium dichromate and anhydrous potassium chromate. Examples of the persulfate compound include sodium persulfate, potassium persulfate, and ammonium persulfate.

  The method for the roughening treatment is not particularly limited. As the method of the roughening treatment, for example, using a 30 to 90 g / L permanganate or permanganate solution and a 30 to 90 g / L sodium hydroxide solution, the treatment temperature is 30 to 85 ° C. and 1 to 40 minutes. A method of treating a precured insulating film under conditions is suitable. This roughening treatment is preferably performed once or twice. It is preferable that the temperature of the said roughening process exists in the range of 50-85 degreeC.

  The arithmetic average roughness Ra of the roughened surface of the insulating film is preferably 50 nm or more, more preferably 70 nm or more, preferably 150 nm or less, more preferably 100 nm or less. When the arithmetic average roughness Ra is not less than the above lower limit and not more than the above upper limit, the adhesion between the insulating layer and the metal layer is further enhanced. The arithmetic average roughness is measured according to JIS B0601-1994.

  Next, after the roughening treatment step, a metal layer 22 is formed by plating on the first surface 2a (upper surface) opposite to the lamination target member 21 side of the roughened insulating film 2B (FIG. 3). (B) Plating step). Here, a metal layer 22 which is a fine metal wiring is formed. After forming a metal layer on the insulating film, a dry film resist is laminated, exposed and developed to form a resist pattern, and then the metal layer is partially removed by etching at the opening of the resist pattern. Then, the resist pattern may be peeled off to form the metal wiring. A dry film resist is laminated on an insulating film, exposed and developed to form a resist pattern, then a metal wiring is formed in the opening of the resist pattern, the resist pattern is peeled off, and a metal wiring is formed. Also good. Moreover, you may form a resist pattern directly, without using a dry film resist.

  By using a laminated film, the metal layer can be made into fine wiring. The L / S of the metal layer which is a fine wiring is preferably 20 μm or less / 20 μm or less, more preferably 15 μm or less / 15 μm or less, and further preferably 10 μm or less / 10 μm or less.

  Next, after the plating step, the pre-cured and roughened insulating film 2B is cured. The roughened insulating film 2B becomes the insulating layer 2C (FIG. 3C, main curing step).

  In the main curing step, the main curing temperature for sufficiently curing the insulating film is preferably 150 ° C. or higher, preferably 200 ° C. or lower, and the main curing time is preferably 0.5 hours or longer, preferably 2 hours or shorter. . The main curing temperature in the main curing step is preferably 20 ° C. or more higher than the precuring temperature in the preliminary curing step.

  In the main curing step, the plurality of insulating films may be cured at once after the plurality of insulating films are laminated.

  A laminated structure can be obtained through the above steps.

  A printed wiring board in which a plurality of metal layers are laminated via a plurality of insulating layers can be obtained by using a build-up method. The laminated structure is preferably a printed wiring board, and is preferably a build-up wiring board. In the build-up method, a step of forming an insulating layer on a substrate using a substrate having a metal portion on the upper surface, a step of further forming a metal portion thereon, and a step of forming an insulating layer thereon And are repeated. Through these steps, a multilayer build-up wiring board is obtained.

(Insulating film material)
[Thermosetting resin]
The thermosetting resin contained in the insulating film is not particularly limited. Examples of the thermosetting resin include epoxy resin, polyimide, and acrylic resin. From the viewpoint of further improving the insulation and mechanical strength, the thermosetting resin is preferably an epoxy resin. As for the said thermosetting resin, only 1 type may be used and 2 or more types may be used together.

  Examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, biphenyl type epoxy resin, biphenyl novolac type epoxy resin, biphenol type epoxy resin, and naphthalene type epoxy resin. Fluorene type epoxy resin, phenol aralkyl type epoxy resin, naphthol aralkyl type epoxy resin, dicyclopentadiene type epoxy resin, anthracene type epoxy resin, epoxy resin having adamantane skeleton, epoxy resin having tricyclodecane skeleton, and triazine nucleus Examples thereof include an epoxy resin having a skeleton. As for the said epoxy resin, only 1 type may be used and 2 or more types may be used together.

[Curing agent]
The curing agent contained in the insulating film is not particularly limited. As for the said hardening | curing agent, only 1 type may be used and 2 or more types may be used together.

  As the curing agent, cyanate ester compound (cyanate ester curing agent), phenol compound (phenol curing agent), amine compound (amine curing agent), thiol compound (thiol curing agent), imidazole compound, phosphine compound, acid anhydride, Examples include active ester compounds and dicyandiamide. Among these, from the viewpoint of forming an insulating layer whose dimensional change due to heat is much smaller, the curing agent is preferably a cyanate ester compound or a phenol compound. The curing agent is preferably a cyanate ester compound, and is preferably a phenol compound. The curing agent preferably has a functional group capable of reacting with the thermosetting group of the thermosetting resin.

  From the viewpoint of further reducing the surface roughness of the roughened insulating layer, further increasing the adhesive strength between the insulating layer and the metal layer, and forming finer wiring on the surface of the insulating layer. The curing agent is preferably a cyanate ester compound, a phenol compound or an active ester compound.

  Examples of the cyanate ester compound include novolac-type cyanate ester resins, bisphenol-type cyanate ester resins, and prepolymers in which these are partially trimerized. As said novolak-type cyanate ester resin, a phenol novolak-type cyanate ester resin, an alkylphenol-type cyanate ester resin, etc. are mentioned. Examples of the bisphenol type cyanate ester resin include bisphenol A type cyanate ester resin, bisphenol E type cyanate ester resin, and tetramethylbisphenol F type cyanate ester resin.

  Commercially available products of the above-mentioned cyanate ester compounds include phenol novolac type cyanate ester resins (Lonza Japan "PT-30" and "PT-60"), and prepolymers (Lonza Japan) in which bisphenol type cyanate ester resins are trimerized. "BA-230S", "BA-3000S", "BTP-1000S", and "BTP-6020S") manufactured by the company.

  The phenol compound is not particularly limited. A conventionally well-known phenol compound can be used as this phenol compound. As for the said phenol compound, only 1 type may be used and 2 or more types may be used together.

  Examples of the phenol compound include novolak type phenol, biphenol type phenol, naphthalene type phenol, dicyclopentadiene type phenol, aralkyl type phenol, dicyclopentadiene type phenol and the like.

  Examples of commercially available phenolic compounds include novolak type phenol (“TD-2091” manufactured by DIC), biphenyl novolac type phenol (“MEH-7851” manufactured by Meiwa Kasei Co., Ltd.), and aralkyl type phenol compound (“MEH manufactured by Meiwa Kasei Co., Ltd.). -7800 "), and phenols having aminotriazine skeletons (" LA-1356 "and" LA3018-50P "manufactured by DIC).

  From the viewpoint of further reducing the surface roughness of the roughened insulating layer, further increasing the adhesive strength between the insulating layer and the metal layer, and forming finer wiring on the surface of the insulating layer. The phenol compound is preferably a biphenyl novolac type phenol compound or an aralkyl type phenol compound.

  The active ester compound is not particularly limited. Commercially available products of the active ester compounds include “HPC8000” and “EXB9416” manufactured by DIC.

  The total content of the thermosetting resin and the curing agent in the solid content A of 100% by weight excluding the filler contained in the insulating film is preferably 75% by weight or more, more preferably 80% by weight or more. , Preferably 99% by weight or less, more preferably 97% by weight or less.

  When the total content of the thermosetting resin and the curing agent is not less than the above lower limit and not more than the above upper limit, a better insulating layer can be obtained and the melt viscosity can be adjusted, so that the dispersion of the filler It becomes possible to prevent the insulating film from spreading and spreading in unintended areas during the curing process. Furthermore, the dimensional change by the heat | fever of an insulating layer can be suppressed further. Moreover, when the total content of the thermosetting resin and the curing agent is less than the lower limit, it is difficult to embed the insulating film in the holes or irregularities of the circuit board. In addition, when the total content of the thermosetting resin and the curing agent exceeds the upper limit, the melt viscosity tends to be too low and the insulating film tends to wet and spread in unintended regions during the curing process. “Solid content A” refers to the sum of the thermosetting resin, the curing agent, and other solid components blended as necessary. Solid content A does not contain a filler. “Solid content” refers to a non-volatile component that does not volatilize during molding or heating.

  The compounding ratio of the thermosetting resin and the curing agent is not particularly limited. The mixing ratio of the thermosetting resin and the curing agent is appropriately determined depending on the type of the thermosetting resin and the curing agent.

[Filler]
Examples of the filler contained in the insulating film include organic fillers and inorganic fillers. Inorganic fillers are preferred. As for the said filler, only 1 type may be used and 2 or more types may be used together.

  Examples of the inorganic filler include silica, talc, clay, mica, hydrotalcite, alumina, magnesium oxide, aluminum hydroxide, aluminum nitride, and boron nitride. The surface roughness of the roughened insulating layer is reduced, the adhesive strength between the insulating layer and the metal layer is further increased, finer wiring is formed on the surface of the insulating layer, and the insulating layer From the viewpoint of imparting good insulation reliability, the inorganic filler is preferably silica or alumina, more preferably silica, and still more preferably fused silica. By using silica, the linear expansion coefficient of the insulating layer is further reduced, the surface roughness of the roughened insulating layer is effectively reduced, and the adhesive strength between the insulating layer and the metal layer is effective. To be high. The shape of silica is preferably substantially spherical.

  The average particle size of the filler is preferably 0.1 μm or more, preferably 20 μm or less, more preferably 1 μm or less. A median diameter (d50) value of 50% is adopted as the average particle diameter of the filler. The average particle size can be measured using a laser diffraction / scattering particle size distribution analyzer.

  The filler is preferably surface-treated, and more preferably surface-treated with a coupling agent. As a result, the surface roughness of the roughened insulating layer is further reduced, the adhesive strength between the insulating layer and the metal layer is further increased, and finer wiring is formed on the surface of the insulating layer. In addition, it is possible to provide the insulating layer with much better inter-wiring insulation reliability and interlayer insulation reliability.

  Examples of the coupling agent include silane coupling agents, titanate coupling agents, and aluminum coupling agents. Examples of the silane coupling agent include amino silane, imidazole silane, vinyl silane, and epoxy silane.

  The content of the filler in 100% by weight of the insulating film is more preferably 55% by weight or more, further preferably 60% by weight or more, and more preferably 80% by weight or less. When the content of the filler is not less than the above lower limit and not more than the above upper limit, the surface roughness of the surface of the roughened insulating layer is further reduced, and the adhesive strength between the insulating layer and the metal layer is further increased. In addition, finer wiring can be formed on the surface of the insulating layer, and at the same time, the thermal expansion coefficient of the insulating layer can be reduced to the same level as that of metallic copper.

  In the present invention, even if the filler content is high or the filler content is 55% by weight or more in 100% by weight of the insulating film, the first base film is peeled off well after lamination. can do.

[solvent]
Examples of the solvent contained in the insulating film include acetone, methanol, ethanol, butanol, 2-propanol, 2-methoxyethanol, 2-ethoxyethanol, 1-methoxy-2-propanol, and 2-acetoxy-1-methoxy. Examples thereof include propane, toluene, xylene, methyl ethyl ketone, N, N-dimethylformamide, methyl isobutyl ketone, N-methyl-pyrrolidone, n-hexane, cyclohexane, cyclohexanone and naphtha which is a mixture. As for the said solvent, only 1 type may be used and 2 or more types may be used together.

  In 100% by weight of the insulating film, the content of the solvent is preferably 1% by weight or more, more preferably 2% by weight or more, preferably 5% by weight or less, more preferably 4% by weight or less. When the content of the solvent is not less than the above lower limit, the insulating film hardly flows excessively. When the content of the solvent is not more than the above upper limit, the solvent is more difficult to remain in the insulating layer.

[Details of other components and epoxy resin materials]
The said insulating film may contain the hardening accelerator, the thermoplastic resin, the leveling agent, etc. as needed.

  By using the curing accelerator, the curing speed of the insulating film is further increased. By rapidly curing the insulating film, the crosslinked structure of the insulating layer becomes uniform. Examples of the curing accelerator include imidazole compounds, phosphorus compounds, amine compounds, and organometallic compounds. As for the said hardening accelerator, only 1 type may be used and 2 or more types may be used together.

  Examples of the thermoplastic resin include phenoxy resin and polyvinyl acetal resin. As for the said thermoplastic resin, only 1 type may be used and 2 or more types may be used together.

  Hereinafter, the present invention will be specifically described by giving examples and comparative examples. The present invention is not limited to the following examples.

In order to form the insulating film, the following materials were used. In the examples , reference examples and comparative examples, the following components were used.

(Thermosetting resin)
Biphenyl type epoxy resin (“NC3000H” manufactured by Nippon Kayaku Co., Ltd.)
Bisphenol A type epoxy resin (DIC Corporation "850S")
Dicyclopentadiene type epoxy resin (“XD1000” manufactured by Nippon Kayaku Co., Ltd.)

(Curing agent)
Phenol novolac curing agent (“H4” by Meiwa Kasei Co., Ltd.)
Aminotriazine-modified phenol novolac curing agent (“LA-1356” manufactured by DIC)
Dicyclopentadiene skeleton active ester curing agent (“HPC8000” manufactured by DIC)

(Filler)
Aminophenylsilane-treated silica (average particle size 0.5 μm (coarse particles of 5 μm or more have been cut), “SOC2” manufactured by Admatechs)

(Curing accelerator)
2-Ethyl-4-methylimidazole (“2E4MZ” manufactured by Shikoku Chemicals)

(Thermoplastic resin)
Bisphenol acetophenone skeleton phenoxy resin ("YX6954" manufactured by Mitsubishi Chemical Corporation)

(Leveling agent)
Leveling agent (“LS-480” manufactured by Enomoto Kasei Co., Ltd.)

(solvent)
Cyclohexanone Methyl ethyl ketone Dimethylformamide (DMF)
toluene

  The following films were prepared as the first and second substrate films.

Release processing PET film 1 (“2511” manufactured by Lintec Corporation, surface free energy 20 mJ / m ² )
Release processing PET film 2 (“T157” manufactured by Lintec Corporation, surface free energy 45 mJ / m ² )
Untreated PET film (“T60M” manufactured by Toray Industries, Inc., surface free energy 47 mJ / m ² )
Polypropylene film ("MA411" manufactured by Oji F-Tex, surface free energy 28mJ / m ² )

Example 1
(1) Production of laminated film In 107 parts by weight of cyclohexanone slurry (solid content 70% by weight) of aminophenylsilane-treated silica ("SOC2" manufactured by Admatechs), biphenyl type epoxy resin ("NC3000H" manufactured by Nippon Kayaku Co., Ltd.) 11 parts by weight, 5 parts by weight of bisphenol A type epoxy resin (“850S” manufactured by DIC), 7.9 parts by weight of cyclohexanone, and 7.7 parts by weight of methyl ethyl ketone are added, and the mixture is stirred at 1200 rpm for 60 minutes. Stir. Next, it was confirmed that there was no undissolved material. Thereafter, 11 parts by weight of a methyl ethyl ketone mixed solution (solid content 50% by weight) of aminotriazine-modified phenol novolak curing agent (“LA-1356” manufactured by DIC), and 3% by weight of phenol novolac curing agent (“H4” manufactured by Meiwa Kasei Co., Ltd.) After stirring for 60 minutes at 1200 rpm and confirming that there was no undissolved material, a mixed solution of bisphenolacetophenone skeleton phenoxy resin (“YX6954” manufactured by Mitsubishi Chemical Corporation) and cyclohexanone (solid content 30 wt%) ) 0.67 parts by weight, 0.1 part by weight of 2-ethyl-4-methylimidazole (“2E4MZ” manufactured by Shikoku Kasei Kogyo Co., Ltd.) and 0.01 part by weight of a leveling agent (“LS-480” manufactured by Enomoto Kasei Co., Ltd.) Was further stirred at 1200 rpm for 30 minutes to obtain a resin varnish.

  Resin with a die coater so that the thickness of the insulating film (resin composition) after drying is 40 μm on the release surface of the release-treated PET film 1 (“2511” manufactured by Lintec Corporation) as the second base film. A varnish was applied and dried at 100 ° C. for 2 minutes (drying conditions) to form an insulating film. Furthermore, the laminated film 1 was obtained by bonding a release-treated PET film 2 (“T157” manufactured by Lintec Corporation) as a first base film with a roll laminator heated to 80 ° C. on the surface of the insulating film. .

(2) Production of laminated structure 1) Lamination process: Double-sided copper-clad laminate (thickness of copper foil on each side 18 μm, substrate thickness 0.7 mm, substrate size 100 mm × 100 mm, “MCL-E679FG” manufactured by Hitachi Chemical Co., Ltd.) ) Was prepared. Both surfaces of the copper foil surface of this double-sided copper-clad laminate were immersed in “Cz8101” manufactured by MEC, and the surface of the copper foil was roughened.

Using a “batch type vacuum laminator MVLP-500-IIA” manufactured by Meiki Seisakusho Co., Ltd., the second base film of the obtained laminated film 1 is peeled off on both sides of the roughened copper clad laminate. Lamination (vacuum lamination) was performed so that the surface of the film faced the copper-clad laminate surface to obtain a laminated structure. The laminating condition was such that the pressure was reduced to 30 hPa or less by reducing the pressure for 30 seconds, and then pressing was performed at 100 ° C. and a pressure of 0.8 MPa for 30 seconds.

2) Film peeling process: In the copper clad laminated board on which the resin composition of the laminated film 1 was laminated, the first base film on both sides was peeled off.

  3) Curing step: The laminated plate was placed in a gear oven having an internal temperature of 150 ° C. for 60 minutes to cure the insulating film to form an insulating layer, thereby obtaining a laminated body.

  4) Roughening treatment step: The laminate having the obtained insulating layer was subjected to the following (a) swelling treatment, and then subjected to the following (b) roughening treatment.

(A) Swelling treatment:
The laminate was placed in a 60 ° C. swelling solution (“Swelling Dip Securigant P” manufactured by Atotech Japan Co., Ltd., “Sodium hydroxide” aqueous solution manufactured by Wako Pure Chemical Industries, Ltd.) and rocked for 20 minutes. Thereafter, it was washed with pure water. That is, the swelling treatment was performed at 60 ° C. for 10 minutes.

(B) Roughening treatment:
The above laminate is placed in a roughened aqueous solution of sodium permanganate at 75 ° C. (“Concentrate Compact CP” manufactured by Atotech Japan Co., Ltd., “Sodium hydroxide” manufactured by Wako Pure Chemical Industries, Ltd.) and shaken for 20 minutes. A cured product was obtained. That is, a roughening treatment was performed at 75 ° C. for 20 minutes.

  The roughened insulating layer was washed for 10 minutes with a 40 ° C. neutralizing solution (“Reduction Securigant P” manufactured by Atotech Japan, “Sulfuric acid” manufactured by Wako Pure Chemical Industries, Ltd.), and further washed with pure water. . Thus, the roughened insulating layer (cured product) was formed on the copper clad laminate.

  The arithmetic average roughness Ra of the roughened surface of the insulating layer was 50 nm.

5) Electroless copper plating step Next, electroless copper plating was performed in the following procedure on the roughened surface of the insulating layer.

  The surface of the insulating layer was treated with a 55 ° C. alkaline cleaner (“Cleaner Securigant 902” manufactured by Atotech Japan) for 5 minutes and degreased and washed. After washing, the insulating layer was treated with a 23 ° C. predip solution (“Predip Neogant B” manufactured by Atotech Japan) for 2 minutes. Thereafter, the insulating layer was treated with an activator solution at 40 ° C. (“Activator Neo Gant 834” manufactured by Atotech Japan) for 5 minutes, and a palladium catalyst was attached. Next, the insulating layer was treated with a reducing solution at 30 ° C. (“Reducer Neogant WA” manufactured by Atotech Japan) for 5 minutes.

  Next, the above insulating layer is made of a chemical copper solution ("Basic Print Gantt MSK-DK" manufactured by Atotech Japan, "Copper Print Gantt MSK" manufactured by Atotech Japan, "Stabilizer Print Gantt MSK" manufactured by Atotech Japan, and Atotech Japan In the “reducer Cu”), electroless plating was performed until the plating thickness reached about 0.5 μm to form a copper plating layer.

  After electroless plating, annealing was performed at a temperature of 120 ° C. for 30 minutes in order to remove the remaining hydrogen gas. All the steps up to the electroless plating step were performed while using a beaker scale with a treatment liquid of 1 L and rocking the insulating layer.

6) Electrolytic copper plating step By feeding power to the electrolessly plated laminated structure, electrolytic copper plating was performed until the thickness became 25 μm, thereby forming an electrolytic copper plating layer. As an electrolytic copper plating, an aqueous copper sulfate solution (“copper sulfate pentahydrate” manufactured by Wako Pure Chemical Industries, Ltd., “sulfuric acid” manufactured by Wako Pure Chemical Industries, Ltd., “basic leveler kaparaside HL” manufactured by Atotech Japan Co., Ltd., “ A current of 0.6 A / cm ² was applied using the corrector Kaparaside GS ”).

7) Main curing step The electroplated laminated structure was heated in a gear oven at 180 ° C. for 60 minutes to be fully cured, thereby improving the adhesion by tightening the anchor portion of the copper plating, and the copper plating was performed. A laminated structure was produced.

8) Wiring formation process About the laminated structure which the process of 5) ended, wiring formation was performed in the following procedures (semi-additive process).

Step 1: Laminating process of dry film resist (DFR) An alkali-soluble DFR (“RY-3525” manufactured by Hitachi Chemical Co., Ltd.) on a PET film as a support is applied to a roll laminator (Taisei Laminator) on an electroless copper plating layer. (VA-700SH)) was laminated under the conditions of a temperature of 150 ° C., a pressure of 0.4 MPa, and a speed of 1.5 m / s to obtain a laminated structure.

Step 2: Exposure and development process Using the obtained laminated structure, L / S = 8 μm / 8 μm, 10 μm / 10 μm, 15 μm / 15 μm, 20 μm using a UV exposure machine (“EXA-1201” manufactured by Oak Manufacturing Co., Ltd.) The DFR was irradiated with UV through a pattern mask of / 20 μm and 30 μm / 30 μm under irradiation conditions of 100 mJ / cm ² .

Step 3: DFR peeling step Thereafter, after holding at 25 ° C. for 60 minutes, the PET film which is a DFR support was peeled off. The surface of the DFR was sprayed with a 1% by weight aqueous sodium carbonate solution at 30 ° C. under a spray pressure of 1.0 kg / cm ² for 80 seconds, developed, and unexposed portions were removed. Thereafter, the film was washed with water at 20 ° C. under a spray pressure of 1.0 kg / cm ^{2 for} 80 seconds and dried to form a negative pattern by DFR.

Step 4: Electrolytic copper plating step 6) In the same manner as the step, a copper plated laminated structure was obtained.

Step 5: DFR peeling and quick etching The DFR remaining between the copper plating wirings was peeled off by immersing the laminated structure after electrolytic copper plating in a caustic soda aqueous solution at 40 ° C. Further, the electroless plating remaining in the fine roughened holes on the surface of the insulating layer below the DFR was removed with a hydrogen peroxide-sulfuric acid-based quick etching solution (“SAC” manufactured by JCU).

(Example 2)
(1) Production of laminated film On the release surface of release-treated PET film 1 (“2511” manufactured by Lintec Corporation) as the second base film, the thickness of the insulating film (resin composition) after drying is 25 μm. Thus, the resin varnish obtained in Example 1 was applied with a die coater and dried at 100 ° C. for 1 minute (drying conditions). Furthermore, the laminated film 2 was obtained by bonding the mold release process PET film 2 ("T157" by Lintec Corporation) as a 1st base film on the resin surface.

(2) Production of Laminated Structure A laminated structure was produced in the same manner as in Example 1 except that the obtained laminated film 2 was used.

( Reference Example 3)
(1) A laminated film 3 was produced in the same manner as in Example 1 except that the drying condition in producing the laminated film was changed to a condition of drying at 100 ° C. for 1 minute.

(2) Production of laminated structure A laminated structure was produced in the same manner as in Example 1 except that the obtained laminated film 3 was used.

( Reference Example 4)
(1) Production of laminated film Biphenyl type epoxy resin (“NC3000H” manufactured by Nippon Kayaku Co., Ltd.) was added to 107 parts by weight of methyl ethyl ketone slurry (solid content: 70% by weight) of aminophenylsilane-treated silica (“SOC2” manufactured by Admatechs). 11 parts by weight, 5 parts by weight of a bisphenol A type epoxy resin (“850S” manufactured by DIC), 13.2 parts by weight of cyclohexanone, and 2.5 parts by weight of methyl ethyl ketone are added, and the mixture is stirred at 1200 rpm for 60 minutes. Stir. Next, it was confirmed that there was no undissolved material. Thereafter, 11 parts by weight of a methyl ethyl ketone mixed solution (solid content 50% by weight) of aminotriazine-modified phenol novolak curing agent (“LA-1356” manufactured by DIC), and 3% by weight of phenol novolac curing agent (“H4” manufactured by Meiwa Kasei Co., Ltd.) After stirring for 60 minutes at 1200 rpm and confirming that there were no undissolved substances, a mixed solution of bisphenolacetophenone skeleton phenoxy resin (“YX6954” manufactured by Mitsubishi Chemical Corporation) and cyclohexanone (solid content: 30% by weight) ) 0.67 parts by weight, 0.1 part by weight of 2-ethyl-4-methylimidazole (“2E4MZ” manufactured by Shikoku Kasei Kogyo Co., Ltd.) and 0.01 part by weight of a leveling agent (“LS-480” manufactured by Enomoto Kasei Co., Ltd.) Was further stirred at 1200 rpm for 30 minutes to obtain a resin varnish.

  Resin with a die coater so that the thickness of the insulating film (resin composition) after drying is 25 μm on the release surface of the release-treated PET film 1 (“2511” manufactured by Lintec Corporation) as the second base film. A varnish was applied and dried at 100 ° C. for 2 minutes (drying conditions) to form an insulating film. Furthermore, the laminated film 4 was obtained by bonding the release film PET film 2 (“T157” manufactured by Lintec Corporation) as a first base film with a roll laminator heated to 80 ° C. on the surface of the insulating film. .

(2) Production of laminated structure A laminated structure was produced in the same manner as in Example 1 except that the obtained laminated film 4 was used.

(Example 5)
(1) A laminated film 5 was produced in the same manner as in Reference Example 4 except that the drying condition in producing the laminated film was changed to a condition of drying at 100 ° C. for 0.5 minutes.

(2) Production of laminated structure A laminated structure was produced in the same manner as in Example 1 except that the obtained laminated film 5 was used.

(Example 6)
(1) Production of laminated film 92 parts by weight of diphenylpentadiene (DCPD) type epoxy resin (Nippon Kayaku Co., Ltd.) in dimethylformaldehyde slurry (solid content 70% by weight) of aminophenylsilane-treated silica ("SOC2" manufactured by Admatechs) "XD1000"), 15 parts by weight, 7 parts by weight of bisphenol A type epoxy resin (DIC, "850S"), 12.9 parts by weight of dimethylformaldehyde, and 0.8 parts by weight of methyl ethyl ketone were added. And stirred for 60 minutes at 1200 rpm. Next, it was confirmed that there was no undissolved material. Thereafter, 6 parts by weight of a methylethylketone mixed solution (solid content 50% by weight) of an aminotriazine-modified phenol novolak curing agent (“LA-1356” manufactured by DIC) and a dicyclopentadiene (DCPD) skeleton active ester curing agent (manufactured by DIC) After adding 16.9 parts by weight of a “HPC8000” toluene mixed solution (solid content: 65% by weight) and stirring at 1200 rpm for 60 minutes, it was confirmed that there was no undissolved material, and then bisphenolacetophenone skeleton phenoxy resin (Mitsubishi) 1.7 parts by weight of a methyl ethyl ketone and cyclohexanone mixed solution (solid content 30% by weight) of “YX6954” manufactured by Kagaku Co., Ltd. and 0.35 parts by weight of 2-ethyl-4-methylimidazole (“2E4MZ” manufactured by Shikoku Kasei Kogyo Co., Ltd.) And 0.01% leveling agent (“LS-480” manufactured by Enomoto Kasei Co., Ltd.) DOO further added, and stirred for 30 minutes at 1200 rpm, to obtain a resin varnish.

  A laminated film 6 was produced in the same manner as in Example 1 except that the above resin varnish was used.

(2) Production of Laminated Structure A laminated structure was produced in the same manner as in Example 1 except that the obtained laminated film 6 was used.

(Comparative Example 1)
(1) Production of laminated film Using a die coater so that the thickness of the insulating film (resin composition) after drying is 40 μm on an untreated PET film (“T60M” manufactured by Toray Industries, Inc.) as the first base film A resin varnish was applied and dried at 100 ° C. for 2 minutes (drying conditions). Furthermore, a laminated film A was obtained by bonding a polypropylene film (“MA411” manufactured by Oji F-Tex Co., Ltd.) as a second base film on the resin surface.

(2) Production of Laminated Structure A laminated structure was produced in the same manner as in Example 1 except that the obtained laminated film A was used and the polypropylene film was peeled off in the film peeling step.

(Comparative Example 2)
(1) Production of laminated film Using a die coater such that the thickness of the insulating film (resin composition) after drying is 25 μm on an untreated PET film (“T60M” manufactured by Toray Industries, Inc.) as the first base film. A resin varnish was applied and dried at 100 ° C. for 1 minute (drying conditions). Furthermore, a laminated film B was obtained by laminating a polypropylene film (“MA411” manufactured by Oji F-Tex Co., Ltd.) as a second base film on the resin surface.

(2) Production of laminated structure A laminated structure was produced in the same manner as in Example 1 except that the obtained laminated film B was used and the polypropylene film was peeled off in the film peeling step.

(Comparative Example 3)
(1) Production of Laminated Film A laminated film C was produced in the same manner as in Comparative Example 1 except that the resin varnish of Example 6 was used.

(2) Production of laminated structure A laminated structure was produced in the same manner as in Comparative Example 1 except that the obtained laminated film C was used.

(Evaluation)
(1) Solvent amount in laminated film The films on both sides of the obtained laminated film were peeled off, and the weight loss before and after heating at 200 ° C. and 60 minutes was measured with an electronic balance for the insulating film (resin composition) alone. The amount of solvent was used.

(2) Presence of the solvent in the insulating film in the laminated film In the obtained laminated film, the solvent in the region up to a depth of 3 μm on the second surface side (laminated side of the second base film) of the insulating film. The existence ratio X2 and the existence ratio X1 of the solvent in the region up to a depth of 3 μm on the first surface side of the insulating film (lamination side of the first base film) were evaluated.

Evaluation method: About each surface, IR spectrum of the surface vicinity was acquired in ATR mode using FT-IR (Thermo ELECTRON company make, NICOLET380). From this spectrum, the main peak attributed to the solvent used (in this example, derived from the stretching vibration of the carbonyl group contained in the ketone or amide (in the case of ketone: 1700 to 1740 cm ⁻¹ , in the case of amide: 1515) ˜1650 cm ⁻¹ )) and the intensity (Xr) of the reference peak (in this case, derived from the stretching vibration of the benzene ring contained in the resin (near 1500 cm ⁻¹ )). About this ratio (Xsol / Xr), the presence state of the solvent was grasped | ascertained by measuring and calculating for every surface.

(3) Existence state of filler in insulating film in laminated film In the obtained laminated film, the filler in the region up to 3 μm deep on the second surface side of the insulating film (the laminated side of the second base film). The abundance ratio Y2 and the abundance ratio Y1 of the filler in the region up to a depth of 3 μm on the first surface side (lamination side of the first base film) of the insulating film were evaluated.

Evaluation method: About each surface of the insulating film, IR spectrum of the surface vicinity was acquired in ATR mode using FT-IR. From this spectrum, the intensity (Ysi) of the main peak due to the filler (in this example, derived from the Si—O—Si bond of silica (1100 to 1000 cm ⁻¹ )) and the reference peak (in this case, The strength (Yr) derived from the stretching vibration of the benzene ring contained in the resin (near 1500 cm ⁻¹ ) was calculated. About this ratio (Ysi / Yr), the presence state of the silica was grasped | ascertained by measuring and calculating for every surface.

(4) Peel strength of first and second base film in laminated film In the obtained laminated film, the peel strength at 25 ° C. of the first base film with respect to the insulating film was evaluated by the following method.

  Evaluation method: After the laminated film was cut to 50 mm × 100 mm, the second base film was peeled off, and then fixed to the SUS substrate with a double-sided tape (arranged so that the surface of the insulating film faces the substrate). The first base film was cut into a 30 mm width with a cutter. The end of the first base film was turned and the peel strength was evaluated by using a 90 ° peel tester (“TE-3001” manufactured by Tester Sangyo Co., Ltd.). The peel strength at 25 ° C. of the second base film with respect to the insulating film was similarly evaluated.

(5) Peel strength of the first base film In the peel process (after the laminating process) for peeling the first base film, the peel strength at 25 ° C. of the first base film with respect to the insulating film is determined as follows. It was evaluated with.

  Evaluation method: After the laminated film was cut to 50 mm × 100 mm, the second base film was peeled off, and then fixed to a copper-clad laminate under predetermined conditions (arranged so that the surface of the insulating film faces the substrate). The first base film (PET film) was cut into a 10 mm width with a cutter. The end of the first base film was turned and the peel strength was evaluated by using a 90 ° peel tester (“TE-3001” manufactured by Tester Sangyo Co., Ltd.).

(6) Film peelability of the first base film In the peeling step (after the laminating process) for peeling the first base film, the surface of the insulating film has streaks after the first base film is peeled off. It was evaluated whether or not foreign matter had adhered to the surface of the insulating film. The film peelability of the first base film was determined according to the following criteria.

[Criteria for determining film peelability of first base film]
○: No streak or foreign matter adhered ×: At least one of streaks or foreign matter adhered

(7) Adhered state of first base film after lamination (2) For sample after vacuum laminating to double-sided copper-clad laminate in production of laminated structure, before peeling first base film, The adhesion state of the first base film after lamination was evaluated according to the following criteria.

[Criteria for Adhering State of First Substrate Film after Lamination]
○: In the process of handling the laminated plate, it does not unintentionally peel. Δ: In the process of handling the laminated plate, only the end of the film is unintentionally peeled. ×: In the process of handling the laminated plate, the film is not intended. More than half peel off

(8) Appearance after lamination (foaming, wrinkles)
(2) In the step of vacuum laminating to a double-sided copper-clad laminate in the production of a laminated structure, the appearance after lamination of the insulating layer on the laminate is visually observed, and the appearance after lamination (foaming, wrinkles) ) Was evaluated according to the following criteria.

[Judgment criteria for appearance (bubbles, wrinkles) after lamination]
○: No bubbles (voids) or wrinkles △: Either bubbles (voids) or wrinkles ×: Both bubbles (voids) and wrinkles

(9) Arithmetic mean roughness Ra of the roughened insulating film
Using a non-contact type surface roughness meter ("WYKO NT1100" manufactured by BEIKO INSTRUMENTS), the measurement range is set to 121 μm × 92 μm by a VSI contact mode and a 50 × lens, and the arithmetic average roughness Ra of the roughened surface is set to It was measured. The arithmetic average roughness Ra was measured at three measurement points selected at random, and the average value of the measurement values was adopted.

(10) Adhesion strength between the insulating layer and the metal layer (peel strength)
In the production of the laminated structures of Examples , Reference Examples, and Comparative Examples, a laminated structure in which electrolytic copper plating was applied to the entire surface without forming wirings was prepared. The copper layer was cut with a cutter to a width of 10 mm. The end of the copper layer was turned, and the copper layer was peeled by 20 mm using a 90 ° peel tester (“TE-3001” manufactured by Tester Sangyo Co., Ltd.). The peel strength at this time was measured.

(11) Fine wiring formability In the production of the laminated structure, it was evaluated whether or not fine wiring with L / S of 8 μm / 8 μm (aspect ratio: 2) could be formed satisfactorily. The fine wiring formability was determined according to the following criteria.

[Judgment criteria for fine wiring formability]
○: L / S = 8 μm / 8 μm fine wiring is observed by SEM, and there is no peeling or defect of the copper plating pattern. X: L / S = 8 μm / 8 μm fine wiring is observed by SEM, and the copper plating pattern is peeled off. Or there is a defect

The details and evaluation results of Examples , Reference Examples and Comparative Examples are shown in Table 1 below.

  From the difference in evaluation results between Examples 1 and 2 and Comparative Examples 1 and 2 shown in Table 1 above, the presence ratio of the solvent in the region up to a depth of 3 μm on the second surface side of the insulating film is It can be seen that the effect of the present invention is excellent when the amount of the solvent is larger than the presence ratio of the solvent in the region up to a depth of 3 μm on the surface side of 1.

  Moreover, the solvent in the area | region to the depth of 3 micrometers on the 2nd surface side of an insulating film from the difference of the evaluation result of Example 1 and the comparative example 1, and the difference of the evaluation result of Example 2 and the comparative example 2 It can be seen that the effect of the present invention is more excellent when the difference in the existence ratio between the existence ratio of the solvent and the existence ratio of the solvent in the region up to 3 μm deep on the first surface side of the insulating film is large.

DESCRIPTION OF SYMBOLS 1,1A ... Laminated film 2 ... Insulating film 2a ... 1st surface 2b ... 2nd surface 2A ... Precured insulating film 2B ... Roughened insulating film 2C ... Insulating layer 3 ... 1st base material Film 4 ... Second base film 21 ... Lamination target member 21a ... Substrate body 21b ... Metal layer 22 ... Metal layer

Claims (7)

An insulating film, and a first base film laminated on the first surface of the insulating film,
The insulating Bei example the second base material film laminated on the second surface opposite to the first surface of the film,
The insulating film includes a thermosetting resin, a curing agent, a filler, and a solvent,
The proportion of the solvent in the region up to a depth of 3 μm on the second surface side of the insulating film is greater than the proportion of the solvent in a region up to a depth of 3 μm on the first surface side of the insulating film. Many
Ratio of the solvent existing ratio in the region up to a depth of 3 μm on the second surface side of the insulating film to the solvent existing ratio in a region up to a depth of 3 μm on the first surface side of the insulating film Is 2 or more and 10 or less,
The insulating film is used by laminating on the member to be laminated in a state where the first base film is laminated from the second surface side,
Before Symbol insulating film before being laminated on the laminated target member from said second surface side, said insulating the second base film from said second surface of the film is peeled off, the laminated film. The filler present in the region up to a depth of 3 μm on the second surface side of the insulating film is greater than the filler present in the region up to a depth of 3 μm on the first surface side of the insulating film. The laminated film according to claim 1, wherein there are many. The ratio of the filler existing in the region up to a depth of 3 μm on the second surface side of the insulating film to the ratio of the filler in the region up to a depth of 3 μm on the first surface of the insulating film The laminated film according to claim 2 , wherein is 1.5 or more and 4.0 or less. The laminated film according to any one of claims 1 to 3 , wherein a peel strength of the second base film with respect to the insulating film is lower than a peel strength of the first base film with respect to the insulating film. The laminated film according to any one of claims 1 to 4 , wherein the peel strength of the first base film with respect to the insulating film is 5 mN / cm or more and 30 mN / cm or less. Claims a stacked film of any one of clauses 1-5, before Symbol by peeling the second base film from said second surface of the insulating film,
A lamination step of laminating the insulating film on the member to be laminated in a state where the first base film is laminated from the second surface side;
The manufacturing method of a laminated structure provided with the peeling process which peels a said 1st base film from the said 1st surface of the said insulating film after the said lamination process. A pre-curing step of pre-curing the insulating film after the peeling step;
After the preliminary curing step, a roughening treatment step of roughening the surface opposite to the lamination target member side of the insulating film,
After the roughening treatment step, a plating step of forming a metal layer by plating on the surface opposite to the lamination target member side of the roughened insulating film,
The manufacturing method of a laminated structure according to claim 6 , further comprising a main curing step of curing the precured insulating film after the plating step.

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