JP2012140010A - Conductor foil laminate, printed circuit board, and multilayer wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a conductor foil laminate, capable of manufacturing a printed circuit board, which satisfactorily reduces a transmission loss particularly in a high-frequency band, which has superior heat resistance, and which satisfactorily suppresses delamination.SOLUTION: The conductor foil laminate 1 is made of a hardened material of a resin composition comprising an insulation layer 2, a conductor layer 6 disposed while facing the insulation layer 2, and an adhesive layer 4 held between the insulation layer 2 and the conductor layer 6. The adhesive layer 4 contains (A) component; a multifunctional epoxy resin, (B) a component; a multifunctional phenol resin, and (C) a component; a polyamide resin.

Description

  The present invention relates to a conductor-clad laminate, a printed wiring board, and a multilayer wiring board.

  Mobile communication devices such as mobile phones, their base station devices, network-related electronic devices such as servers and routers, or large computers are required to transmit and process large amounts of information with low loss and high speed. ing. In order to meet such demands, the frequency of electric signals handled is increasing in printed wiring boards mounted on the above-described devices. However, since the electrical signal has a property of being easily attenuated as the frequency becomes higher, a printed wiring board that handles the electrical signal of higher frequency is required to have a transmission loss lower than before.

  In order to obtain a printed wiring board with low transmission loss, conventionally, a thermoplastic resin material containing a fluorine-based resin having a low relative dielectric constant and dielectric loss tangent has been used as a substrate material for the printed wiring board. However, since this fluororesin generally has a high melt viscosity and low fluidity, it is not always easy to mold, for example, it is necessary to set high temperature and high pressure conditions during press molding. Moreover, as a printed wiring board material used for the above-mentioned communication apparatus etc., in addition to workability, it had the fault that dimension stability and adhesiveness with metal plating were inadequate.

  Therefore, an attempt has been made to use a thermosetting resin composition having a low relative dielectric constant and dielectric loss tangent instead of the thermoplastic resin material. For example, the following are known as thermosetting resin compositions used as raw materials for dielectric materials such as electronic devices described above. That is, Patent Documents 1 to 3 disclose resin compositions containing triallyl cyanurate or triallyl isocyanurate. Patent Documents 1, 2, 4, and 5 disclose resin compositions containing polybutadiene. Furthermore, Patent Document 6 discloses a resin composition containing a thermosetting polyphenylene ether provided with a radical crosslinkable functional group such as an allyl group, and the above-mentioned triallyl cyanurate and triallyl isocyanurate. Yes. In these patent documents, it is generally shown that the above-mentioned thermosetting resin composition does not have many polar groups after curing, so that transmission loss can be reduced.

  In the printed wiring board, it is desirable that the adhesiveness between the insulating layer and the conductive layer provided thereon is high. If the adhesiveness between the insulating layer and the conductive layer is low, inconveniences such as separation of the two during use tend to occur. A printed wiring board is often formed by processing a conductive foil of a metal-clad laminate in which a conductive foil is laminated on an insulating layer, but in order to obtain excellent adhesion between the insulating layer and the conductive layer It is also important that the adhesion between the insulating layer and the conductive foil in this metal-clad laminate is high.

  From such a viewpoint, a metal-clad laminate obtained by laminating a prepreg sheet with a copper foil coated with polybutadiene modified with epoxy, maleic acid, carboxylic acid or the like is known (see Patent Documents 7 and 8). . A printed wiring board in which a layer containing an epoxy compound or a polyamideimide compound is interposed between an insulating layer and a conductor layer is also known (see Patent Documents 9 and 10). Furthermore, a method of arranging an adhesion promoting elastomer layer such as ethylene-propylene elastomer between the copper foil and the insulating layer has also been proposed (see Patent Document 11).

Japanese Examined Patent Publication No. 6-69746 Japanese Patent Publication No. 7-47689 JP 2002-265777 A Japanese Patent Publication No.58-21925 JP-A-10-117052 Japanese Patent Publication No. 6-92533 JP 54-74883 A JP 55-86744 A JP 2005-167172 A JP 2005-167173 A JP-A-2005-502192

  By the way, in recent years, it has been required for electronic devices and the like as described above to cope with higher frequency electrical signals. However, for example, a low dielectric constant, low dielectric loss tangent resin as described in Patent Documents 1 to 6 described above is used as a dielectric material, and only a low transmission loss of an electric signal in an insulating layer (dielectric layer) is achieved. Therefore, it has become difficult to sufficiently cope with such high frequencies. The transmission loss of electrical signals is caused by both the loss due to the insulating layer (dielectric loss) and the loss due to the conductive layer (conductor loss). In response to the recent increase in frequency, it is necessary to reduce not only the dielectric loss but also the conductor loss by improving the conventional dielectric material.

  In particular, in most printed wiring boards (multilayer wiring boards) that have been put into practical use in recent years, the thickness of the insulating layer disposed between the signal layer, which is a conductive layer, and the ground layer is as thin as 200 μm or less. . Therefore, when a resin having a dielectric constant or a dielectric loss tangent that is somewhat low is employed as the material of the insulating layer, the conductor loss rather than the dielectric loss is dominant as the transmission loss of the entire wiring board.

  Here, as a method for reducing the conductor loss, there is a method using a metal foil having a small surface unevenness on the surface of the conductive layer that is bonded to the insulating layer (roughened surface, hereinafter referred to as “M surface”). Can be mentioned. Specifically, a metal foil provided with a metal foil having a surface roughness (ten-point average roughness; Rz) of M surface of 4 μm or less (such metal foil is hereinafter referred to as “low-roughened foil”). It is conceivable to use a laminate.

  Therefore, based on the above findings, the present inventors first have a low dielectric constant and low dielectric loss tangent resin that is cured by polymerization of a vinyl group or an allyl group, as described in Patent Documents 1 to 6. The printed wiring board obtained by using together with the low roughening foil mentioned above was produced and examined in detail. As a result, such a printed wiring board has a low polarity of the insulating layer and a low anchoring effect due to the unevenness of the M surface of the metal foil, so that the adhesive force (bonding force) between the insulating layer and the conductive layer is weak. It was confirmed that peeling easily occurred between these layers. In particular, such peeling tends to be prominent when the printed wiring board is heated (particularly when heated after moisture absorption). Thus, when the above-described resin is used as a dielectric material, it is difficult to sufficiently secure the adhesion between the insulating layer and the conductive layer if a low-roughened foil is used to reduce conductor loss. It has been found.

  Further, by applying the means described in Patent Documents 7 and 8, the insulating layer and a low-roughened copper foil having an M-plane Rz of 4 μm or less are bonded together via a modified polybutadiene, and a printed wiring board is obtained. Produced. As a result, it was found that a sufficiently high copper foil peeling strength could not be obtained, and that heat resistance (particularly heat resistance during moisture absorption) was reduced.

  Furthermore, by applying the means described in Patent Documents 9 and 10, a polyamideimide resin having a thickness of 0.1 to 5 μm was previously provided on the surface of the low-roughened copper foil having an Rz of M surface of 4 μm or less. A printed wiring board was produced using a copper foil with an adhesive layer. In this case, it was confirmed that high copper foil peeling strength was obtained. However, in such a printed wiring board, the anchor effect resulting from the unevenness of the M surface of the metal foil is reduced. For this reason, the adhesive force between the polyamide-imide resin and the insulating layer becomes weak (bonding force). For example, when heated (especially when heated after moisture absorption), peeling between these layers occurs easily. Turned out to be.

  Further, by applying the means described in Patent Document 11, adhesion containing an elastomer such as a styrene-butadiene elastomer having a thickness of 3 to 15 μm on the surface of a low-roughened copper foil whose Rz on the M surface is 4 μm or less. A printed wiring board was prepared using a copper foil with an adhesive layer provided with an accelerating elastomer layer in advance. In this case, although high copper foil peeling strength is shown, the anchor effect resulting from the unevenness | corrugation of the M surface of metal foil falls. As a result, it has been found that the adhesive force between the insulating layers via the adhesion promoting elastomer layer becomes weak (bonding force), and peeling easily occurs between these layers when heated.

  Therefore, the present invention has been made in view of such circumstances, and in particular, a print that can satisfactorily reduce transmission loss in a high frequency band, has excellent heat resistance, and sufficiently suppresses delamination between layers. An object is to provide a conductor-clad laminate capable of producing a wiring board. Another object of the present invention is to provide a printed wiring board and a multilayer wiring board obtained using such a conductor-clad laminate.

  In order to achieve the above object, the present invention includes an insulating layer, a conductor layer disposed opposite to the insulating layer, and an adhesive layer sandwiched between the insulating layer and the conductor layer. The present invention provides a conductor-clad laminate comprising a cured product of a resin composition comprising: a component; a polyfunctional epoxy resin; and a component (B); a polyfunctional phenol resin; and a component (C); a polyamide resin. Note that the adhesive layer may be referred to as an “adhesive layer” before and after curing. Therefore, in this specification, the adhesive layer before the adhesive layer in the conductor-clad laminate of the present invention is cured is referred to as “adhesive layer before curing” and is distinguished from the “adhesive layer” after curing.

  The adhesive layer in the conductor-clad laminate of the present invention is made of a cured product of the curable resin composition containing the components (A) to (C). Since this cured product contains a cured product of polyfunctional epoxy resin and polyfunctional phenolic resin and polyamideimide by curing, it has extremely good adhesion to insulating layers having characteristics such as low roughened foil and low dielectric constant. It will be excellent. Furthermore, since this cured product is a cured product of the above three components, it also has excellent heat resistance.

  Therefore, when a printed wiring board (printed wiring board) or a multilayer wiring board is manufactured using such a conductor-clad laminate as will be described later, the insulating layer and the conductor layer (conductor foil) Strong adhesion is achieved through the adhesive layer in the conductor-clad laminate, and the separation of these can be greatly prevented. Further, due to the low dielectric constant and low dielectric loss tangent characteristics of the adhesive layer, it is possible to significantly reduce transmission loss. Furthermore, due to the adhesive layer having excellent heat resistance, excellent heat resistance as a whole can be obtained. In this specification, an insulating layer that is a substrate material such as a conductor-clad laminate or a printed wiring board (printed wiring board) is referred to as an “insulating layer” or “insulating resin layer”, and an “adhesive layer” in the conductor-clad laminate. It will be distinguished from.

  In the conductor-clad laminate of the present invention, the (A) component and the (B) component in the curable resin composition that is cured to form an adhesive layer have a glass transition temperature of 150 ° C. or higher after curing of these mixtures. It is preferable. By satisfying such conditions, the heat resistance of the adhesive layer is further improved, and the printed wiring board obtained using the conductor-clad laminate of the present invention also has excellent heat resistance in a practical temperature range. become. In addition, this glass transition temperature (Tg) can be measured by differential scanning calorimetry (DSC) based on JIS-K7121-1987.

  In the curable resin composition, the polyfunctional epoxy resin (A) is a phenol novolac type epoxy resin, a cresol novolak type epoxy resin, a brominated phenol novolak type epoxy resin, a bisphenol A novolak type epoxy resin, or a biphenyl type epoxy resin. , Naphthalene skeleton-containing epoxy resins, aralkylene skeleton-containing epoxy resins, biphenyl-aralkylene skeleton-containing epoxy resins, phenol salicylaldehyde novolac-type epoxy resins, lower alkyl group-substituted phenol salicylaldehyde novolac-type epoxy resins, dicyclopentadiene skeleton-containing epoxy resins, many It is preferable to contain at least one polyfunctional epoxy resin selected from the group consisting of a functional glycidylamine type epoxy resin and a polyfunctional alicyclic epoxy resin.

  The polyfunctional phenol resin as component (B) is an aralkyl type phenol resin, a dicyclopentadiene type phenol resin, a salicylaldehyde type phenol resin, a copolymer type resin of a benzaldehyde type phenol resin and an aralkyl type phenol resin, and It is preferable to contain at least one polyfunctional phenol resin selected from the group consisting of novolak type phenol resins.

  These polyfunctional epoxy resins or polyfunctional phenol resins can impart excellent adhesion and heat resistance to the adhesive layer by being combined with other components in the present invention.

  Furthermore, the polyamideimide as the component (C) preferably contains a structural unit composed of a saturated hydrocarbon. Using polyamide imide containing a structural unit consisting of saturated hydrocarbons will improve the adhesion of the adhesive layer to the conductor layer, insulating layer, etc., and particularly maintain good adhesion even during moisture absorption. Become so. As a result, a printed wiring board or the like obtained using the conductor-clad laminate of the present invention has a characteristic that it is extremely difficult to cause delamination even after moisture absorption.

  In the curable resin composition that is cured to be an adhesive layer, the blending ratio of the component (C) is preferably 10 to 400 parts by mass with respect to 100 parts by mass in total of the component (A) and the component (B). . When the blending ratio of the component (C) is within such a range, good adhesiveness can be obtained, and the toughness, heat resistance, chemical resistance and the like of the adhesive layer tend to be particularly improved.

  The adhesive layer in the conductor-clad laminate preferably has a thickness of 0.1 to 10 μm. According to the adhesive layer having such a thickness, sufficient adhesion with the conductor layer can be obtained, and the dielectric loss can be reduced well.

  Furthermore, it is preferable that the ten-point average roughness (Rz) of the surface on the adhesive layer side in the conductor layer is 4 μm or less. When the surface roughness of the M surface is 4 μm or less, the conductor loss due to the conductive layer formed from this conductor layer is reduced, and the printed wiring board obtained using the conductor-clad laminate of the present invention has only dielectric loss. In addition, the conductor loss is reduced well. Here, the ten-point average roughness (Rz) refers to the ten-point average roughness defined in JIS B0601-1994.

  In the conductor-clad laminate of the present invention, the insulating layer is composed of an insulating resin and a base material disposed in the insulating resin, and the base material is made of glass, paper, and an organic polymer compound. It is preferable to have a woven or nonwoven fabric of fibers made of at least one material selected from the group. As a result, it is possible to more reliably reduce transmission loss, improve heat resistance, and suppress delamination between layers.

  Moreover, it is preferable that an insulating layer contains resin which has an ethylenically unsaturated bond as insulating resin. More specifically, the insulating resin preferably contains at least one resin selected from the group consisting of polybutadiene, polytriallyl cyanurate, polytriallyl isocyanurate, unsaturated group-containing polyphenylene ether and maleimide compound. Since these resins have a low dielectric constant and a low dielectric loss tangent, dielectric loss can be greatly reduced.

  Alternatively, the insulating resin preferably contains at least one resin selected from the group consisting of polyphenylene ether and thermoplastic elastomer. Since these resins also have a low dielectric constant and low dielectric loss tangent, dielectric loss can be greatly reduced.

  The insulating layer preferably has a relative dielectric constant of 4.0 or less at 1 GHz. According to the insulating layer satisfying such conditions, the dielectric loss can be greatly reduced. As a result, the wiring board obtained from this conductor-clad laminate has extremely low transmission loss.

  The conductor-clad laminate of the present invention includes an insulating resin and a base material disposed in the insulating resin on the layer before curing in the conductor foil with an adhesive layer, which includes the layer before curing of the adhesive layer on the conductor foil. It is preferable that the laminate is obtained by laminating a film including the above, and then heating and pressurizing the laminate. The conductor-clad laminate thus obtained has particularly good adhesion between the adhesive layer and the conductor layer.

  Furthermore, the printed wiring board according to the present invention can be applied as a printed wiring board, and is obtained by processing the conductor foil in the conductor-clad laminate of the present invention so as to have a predetermined circuit pattern. It is. Such a printed wiring board, even when using a low-roughening foil, it is very difficult to peel off the circuit pattern made of the conductive foil and the insulating resin layer, and since the adhesive layer has excellent heat resistance, As a whole, it has excellent heat resistance.

  Furthermore, this invention can provide the multilayer wiring board which is hard to produce peeling between layers and has high heat resistance by providing the printed wiring board of the said invention. That is, the multilayer wiring board of the present invention includes a core substrate having at least one printed wiring board and an outer wiring board having at least one printed wiring board disposed on at least one surface of the core substrate. Then, at least one of the printed wiring boards in the core substrate is the printed wiring board of the present invention.

  Note that high-frequency compatible printed wiring boards applied to electronic devices as described above are required to have good impedance control as well as low transmission loss. In order to realize this, it is important to improve the accuracy for forming a good pattern width of the conductive layer during the production of the printed wiring board. Here, when a conductor foil having a small surface roughness such as a low profile foil is used, it tends to be advantageous for improving the accuracy in forming the conductor pattern and for further fine patterning.

  Under such circumstances, according to the conductor-clad laminate of the present invention, a low-roughened foil is used, and an insulating resin material having a low dielectric constant and a low dielectric loss tangent is used for the insulating layer. However, sufficient adhesion between the insulating layer and the conductor layer can be obtained. Therefore, according to the printed wiring board produced using the conductor-clad laminate of the present invention, not only low transmission loss but also good impedance control can be realized.

  The reason why the conductor-clad laminate of the present invention can provide the above excellent adhesiveness is not clear in detail at present, but the present inventors presume as follows. . For example, when using a low-roughened foil as a conductor layer, in addition to lowering the adhesion of the low-roughened foil to the insulating layer, etc., multilayering is performed using a conductor-clad laminate having this low-roughened foil. Even in such a case, delamination may easily occur. That is, by removing the conductor layer of the conductor-clad laminate in which the low-roughening foil with Mz Rz of 4 μm or less is laminated on both surfaces of the insulating resin layer, the prepreg and the conductor foil are sequentially stacked on the surface. When producing a multilayer laminated board and also a printed wiring board, the roughness transferred to the inner insulating resin layer by the low-roughening foil is also small.

  In the multilayer laminate obtained in this way, the anchor effect between the insulating resin layer and the prepreg is reduced as compared with the case where a general copper foil (Rz is 6 μm or more) is used as the conductor foil. As a result, the adhesive force (bonding force) between the insulating resin layer and the prepreg is reduced. Therefore, as a result, the conductive foil disposed on the surface of the prepreg is easily peeled from the insulating resin layer. In particular, such a tendency is remarkable when heating (especially heating after moisture absorption) is performed.

  In such a case, by using a conductor-clad laminate in which a conductor layer and an insulating resin layer are laminated via an adhesive layer, the above-described decrease in adhesive force can be reduced. That is, when a multilayer laminate is formed using this conductor-clad laminate, an adhesive layer is interposed between the insulating resin layer and the prepreg, so that the adhesion between the two layers is improved to some extent. .

  However, in this case, when only a polyamideimide or a resin material in which a polyamideimide and an epoxy resin are combined is applied to the adhesive layer, the heat resistance is insufficient for application as a printed wiring board. Although this resin material can show favorable adhesiveness, it is thought that it is because heat resistance after moisture absorption is not so good because it tends to cause hydrogen bonding with water and the like.

  On the other hand, in the conductor-clad laminate of the present invention, the components (A) and (B) contained in the pre-curing adhesive layer are excellent in heat resistance after curing (particularly heat resistance after moisture absorption). Therefore, the multilayer laminated board and printed wiring board obtained by using such a conductor-clad laminated board have excellent heat resistance as a whole. In addition, since the components (A) and (B) are excellent in adhesion to the insulating resin layer and the conductor layer, the adhesive layer is sufficient even if the amount of the polyamideimide (C) component is reduced. High adhesion can be maintained. In general, polyamideimide tends to lower the heat resistance of the adhesive layer. Therefore, according to the conductor-clad laminate of the present invention, even if the amount of polyamideimide added is minimized, even more heat resistance is achieved. This will improve the performance.

  Therefore, printed wiring boards and multilayer wiring boards obtained using the conductor-clad laminate of the present invention have a specific adhesive layer between the conductive layer (circuit pattern) and the insulating layer, so that the adhesive surface is smooth. Even when a conductive layer and an insulating layer with little dielectric loss are provided, the adhesiveness between the conductive layer and the insulating layer is good and the heat resistance is also excellent.

  Advantageous Effects of Invention According to the present invention, it is possible to provide a conductor-clad laminate that can satisfactorily reduce transmission loss in a high-frequency band and that can produce a printed wiring board that does not easily cause delamination between layers. It becomes. Moreover, it becomes possible to provide a metal-clad laminate, a printed wiring board, and a multilayer wiring board obtained using such a conductor-clad laminate.

It is a figure which shows typically the cross-sectional structure of the conductor clad laminated board of suitable embodiment. It is a mimetic diagram showing the section structure of the wiring board of an embodiment. It is a schematic diagram which shows the cross-section of the multilayer wiring board of embodiment.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings as necessary. In the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted. Further, the positional relationship such as up, down, left and right is based on the positional relationship shown in the drawings unless otherwise specified. Further, the dimensional ratios in the drawings are not limited to the illustrated ratios.

[Conductor-clad laminate]
First, a conductor-clad laminate according to a preferred embodiment will be described. FIG. 1 is a partial cross-sectional view showing a conductor-clad laminate according to a preferred embodiment. A conductor-clad laminate 1 shown in FIG. 1 has a structure in which an insulating layer 2, an adhesive layer 4, and a conductor layer 6 are laminated in this order.

(Insulating layer)
As the insulating layer 6 in the conductor-clad laminate 1, for example, one obtained by pasting a predetermined number of known prepregs and then heating and / or pressing is employed. As the prepreg, the prepared resin varnish was impregnated into a woven or non-woven fabric of fiber made of at least one material selected from the group consisting of glass, paper material and organic polymer compound, and prepared by a known method Can be used. Examples of the fiber (glass fiber) made of glass include E glass, S glass, NE glass, D glass, and Q glass. Examples of the fiber (organic fiber) made of an organic polymer compound include aramid, fluororesin, and polyester. And liquid crystalline polymers. These are used singly or in combination of two or more.

  As the resin contained in the resin varnish, an insulating resin (insulating resin) is preferable, and a resin having an ethylenically unsaturated bond is more preferable. Examples of such an insulating resin include polybutadiene, polytriallyl cyanurate, polytriallyl isocyanurate, unsaturated group-containing polyphenylene ether having a structural unit containing an ethylenically unsaturated bond, and a maleimide compound. Since these insulating resins have a low relative dielectric constant and dielectric loss tangent, transmission loss of the wiring board obtained from the conductor-clad laminate 1 can be reduced. These are used singly or in combination of two or more.

  The insulating resin preferably contains at least one selected from the group consisting of polyphenylene ether and a thermoplastic elastomer, and a saturated thermoplastic elastomer is particularly preferable as the thermoplastic elastomer. Since these resins have a low dielectric constant and a low dielectric loss tangent, dielectric loss can be greatly reduced.

  The maleimide compound (polymaleimide) as the insulating resin may be a resin having a maleimide skeleton in the main chain, or a resin having a maleimide group in the side chain and / or terminal. However, it is preferable to use a maleimide compound as a crosslinking aid for the insulating resin. This not only reduces the transmission loss of the wiring board obtained from the conductor-clad laminate 1, but also improves the curability, so that the thermal expansion coefficient and heat resistance of the resin become better.

  The dielectric constant of the insulating layer 6 is preferably 4.0 or less at 1 GHz. According to the insulating layer 6 satisfying such conditions, the dielectric loss can be greatly reduced. As a result, the printed wiring board obtained from this conductor-clad laminate has extremely low transmission loss.

(Conductor layer)
The conductor layer 6 is not particularly limited as long as it is conventionally applied to a conductive layer such as a printed wiring board. For example, a conductor layer composed of a metal foil is employed. More specifically, for example, copper foil, nickel foil, aluminum foil or the like can be applied. Of these, electrolytic copper foil or rolled copper foil is preferable. In addition, when a metal foil is applied as the conductor layer 6, a barrier layer forming treatment with nickel, tin, zinc, chromium, molybdenum, cobalt, etc. is performed from the viewpoint of improving the rust prevention, chemical resistance, heat resistance, etc. Preferably. Further, from the viewpoint of improving the adhesion with the insulating layer, it is preferable that surface treatment such as surface roughening treatment or treatment with a silane coupling agent is performed.

  Among these surface treatments, with regard to the surface roughening treatment, the surface roughness (Rz) on the M surface of the conductor layer 6 on the side in contact with the adhesive layer 4 is preferably 4 μm or less, more preferably 3 μm or less. It is preferable that the treatment is performed. Thereby, it exists in the tendency which can improve a high frequency transmission characteristic further. The silane coupling agent used for the silane coupling agent treatment is not particularly limited, but epoxy silane, amino silane, cationic silane, vinyl silane, acryloxy silane, methacryloxy silane, ureido silane, mercapto silane, sulfide silane, An isocyanate silane etc. are mentioned.

  The conductor layer 6 may have a single-layer structure made of one kind of metal material, may have a single-layer structure made of a plurality of metal materials, or has a laminated structure in which a plurality of metal layers of different materials are laminated. There may be. Moreover, the thickness of the conductor layer 6 is not specifically limited. The metal foil applied to the conductor layer 6 is, for example, copper foil F2-WS (Furukawa Circuit Foil, trade name, Rz = 2.0 μm), F0-WS (Furukawa Circuit Foil, trade name, Rz = 1.2 μm), 3EC-VLP (manufactured by Mitsui Kinzoku Co., Ltd., trade name, Rz = 3.0 μm) and the like are commercially available and suitable.

(Adhesive layer)
The adhesive layer 4 in the conductor-clad laminate 1 is composed of (A) component; polyfunctional epoxy resin, (B) component; polyfunctional phenol resin, and (C) component; curing of curable resin composition containing polyamideimide. It is a layer consisting of things. The thickness of the adhesive layer 4 is preferably 0.1 to 10 μm. If this thickness is less than 0.1 μm, it tends to be difficult to obtain sufficient peel strength of the conductor layer (conductor foil) or the like. On the other hand, when the thickness exceeds 10 μm, the high-frequency transmission characteristics of the metal-clad laminate 1 tend to deteriorate. Hereinafter, each component of the curable resin composition that cures to become the adhesive layer 4 will be described.

  First, the component (A) will be described.

  The polyfunctional epoxy resin as the component (A) is a compound having a plurality of epoxy groups in one molecule, and is a compound in which a plurality of molecules can be bonded by reaction between epoxy groups. Examples of such component (A) include bisphenol A type epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin, brominated phenol novolak type epoxy resin, bisphenol A novolak type epoxy resin, biphenyl type epoxy resin, Naphthalene skeleton-containing epoxy resin, aralkylene skeleton-containing epoxy resin, biphenyl-aralkylene skeleton epoxy resin, phenol salicylaldehyde novolak type epoxy resin, lower alkyl group-substituted phenol salicylaldehyde novolak type epoxy resin, dicyclopentadiene skeleton containing epoxy resin, polyfunctional glycidyl Examples include amine type epoxy resins and polyfunctional alicyclic epoxy resins. As the component (A), one of these may be contained alone, or two or more may be contained in combination.

  Especially, as (A) component, a cresol novolak type epoxy resin, a biphenyl type epoxy resin, or a phenol novolak type epoxy resin is preferable. By including these polyfunctional epoxy resins as the component (A), excellent adhesion and electrical properties by the adhesive layer 4 can be easily obtained after curing.

  Next, the component (B) will be described.

  The polyfunctional phenol compound (B) is a compound having a plurality of phenolic hydroxyl groups in one molecule, and functions as a curing agent for the polyfunctional epoxy resin (A). Examples of the component (B) include aralkyl type phenol resins, dicyclopentadiene type phenol resins, salicylaldehyde type phenol resins, benzaldehyde type phenol resins and aralkyl type phenol resins, and novolac type phenol resins. It is done. (B) As a component, these compounds may be contained independently and may be contained in combination of 2 or more type.

  The above-mentioned component (A) and component (B) are preferably selected such that the glass transition temperature after curing of the mixture obtained by mixing them is 150 ° C. or higher. When the cured product of the mixture of the component (A) and the component (B) satisfies such conditions, the heat resistance of the adhesive layer 4 is further improved, and the printed wiring board obtained using the conductor-clad laminate is also provided. It has excellent heat resistance in a practical temperature range.

  Next, the component (C) will be described.

  The polyamideimide as the component (C) is a polymer having a repeating unit including an amide structure and an imide structure. The component (C) in the present embodiment preferably has a weight average molecular weight (hereinafter referred to as “Mw”) of 20,000 to 300,000. Here, Mw can be measured by gel permeation chromatography, and a value converted by a calibration curve created using standard polystyrene can be applied.

  When the Mw of the component (C) is less than 20000, the conductor-clad laminate 1 obtained using the curable resin composition containing the component (C), and further using the conductor-clad laminate 1 are used. In a printed wiring board, the adhesion between the adhesive layer and the conductor layer (conductor foil) tends to be disadvantageously reduced. In particular, this tendency becomes more remarkable when the thickness of the conductor layer is reduced. On the other hand, even if Mw exceeds 300,000, the fluidity of the polyamideimide is deteriorated, so that the adhesiveness between the adhesive layer and the conductor layer tends to be lowered. This tendency is also remarkable when the thickness of the conductor layer is reduced.

  (C) It is preferable that the component contains the structural unit which consists of a saturated hydrocarbon in the molecule | numerator. When the component (C) contains a saturated hydrocarbon, the adhesiveness of the adhesive layer to the conductor layer and the like is improved. In addition, since the moisture resistance of the component (C) is improved, the adhesion by the adhesive layer after moisture absorption is also favorably maintained. As a result, the moisture and heat resistance of a printed wiring board obtained using the conductor-clad laminate 1 of the present embodiment is improved. The component (C) particularly preferably has a structural unit composed of a saturated hydrocarbon in the main chain.

  The structural unit consisting of this saturated hydrocarbon is particularly preferably a saturated alicyclic hydrocarbon group. When it has a saturated alicyclic hydrocarbon group, the adhesiveness at the time of moisture absorption by the adhesive layer becomes particularly good, and the adhesive layer comes to have a high Tg, and the heat resistance of a printed wiring board or the like provided with the adhesive layer is further increased. improves. And the effect as mentioned above exists in the tendency which is acquired stably especially when Mw of (C) component is 50,000 or more.

  The component (C) more preferably contains a siloxane structure in the main chain. A siloxane structure is a structural unit in which silicon atoms and oxygen atoms having a predetermined substituent are alternately and repeatedly bonded. The component (C) contains a siloxane structure in the main chain, so that the properties such as the elastic modulus and flexibility of the adhesive layer 4 can be improved, and the durability of the obtained printed wiring board can be improved and cured. The drying efficiency of the conductive resin composition tends to be good, and the adhesive layer 4 tends to be formed easily.

  Examples of the polyamideimide as component (C) include polyamideimide synthesized by a so-called isocyanate method by reaction of trimellitic anhydride and aromatic diisocyanate. As a specific example of this isocyanate method, a method in which an aromatic tricarboxylic acid anhydride and a diamine compound having an ether bond are reacted in the presence of excess diamine compound and then reacted with diisocyanate (see, for example, Japanese Patent No. 2897186). And a method of reacting an aromatic diamine compound and trimellitic anhydride (for example, a method described in JP-A No. 04-182466).

  Further, the component (C) containing a siloxane structure in the main chain can also be synthesized according to the isocyanate method. Specific examples of the synthesis method include a method of polycondensing an aromatic tricarboxylic acid anhydride, an aromatic diisocyanate and a siloxane diamine compound (for example, a method described in JP-A No. 05-009254), an aromatic dicarboxylic acid or A method of polycondensing an aromatic tricarboxylic acid and a siloxane diamine compound (for example, a method described in JP-A-06-116517), a diamine compound having three or more aromatic rings and a mixture containing siloxane diamine and trimellitic anhydride Examples include a method of reacting a mixture containing diimide dicarboxylic acid obtained by reacting with an acid with an aromatic diisocyanate (for example, a method described in JP-A-06-116517). According to the curable resin composition of the present embodiment which is cured to form the adhesive layer 4, even when the component (C) synthesized by these known methods is used, a sufficiently high metal foil peeling strength is obtained. It is done.

  Hereinafter, an example of a method for producing a polyamideimide having a structural unit (particularly a saturated alicyclic hydrocarbon group) composed of a saturated hydrocarbon suitable as the component (C) in the main chain will be described in detail.

  Such a polyamideimide is, for example, after derivatizing an imide group-containing dicarboxylic acid obtained by reacting a diamine compound having a saturated hydrocarbon group with trimellitic anhydride into an acid halide, or using a condensing agent. It can be obtained by reacting with a diamine compound. Alternatively, it can also be obtained by reacting a diisocyanate with an imide group-containing dicarboxylic acid obtained by reacting a diamine compound having a saturated hydrocarbon group with trimellitic anhydride. A polyamide having a saturated alicyclic hydrocarbon group can be obtained by using a diamine compound having a saturated alicyclic hydrocarbon group as a saturated hydrocarbon group in these methods.

ここで、式（１ａ）及び（１ｂ）中、Ｌ^１は、ハロゲン置換されていてもよい炭素数１〜３の２価の脂肪族炭化水素基、スルホニル基、オキシ基、カルボニル基、単結合又は下記式（２ａ）又は（２ｂ）で表される２価の基を示し、Ｌ^２はハロゲン置換されていてもよい炭素数１〜３の２価の脂肪族炭化水素基、スルホニル基、オキシ基又はカルボニル基を示し、Ｒ^５、Ｒ^６及びＲ^７は、それぞれ独立に、水素原子、水酸基、メトキシ基、ハロゲン置換されていてもよいメチル基を示す。 Specific examples of the diamine compound having a saturated hydrocarbon group include compounds represented by the following general formula (1a) or (1b).

Here, in the formulas (1a) and (1b), L ¹ is an optionally halogenated divalent aliphatic hydrocarbon group having 1 to 3 carbon atoms, sulfonyl group, oxy group, carbonyl group, single bond Or a divalent group represented by the following formula (2a) or (2b), wherein L ² is a halogenated halogenated divalent aliphatic hydrocarbon group having 1 to 3 carbon atoms, sulfonyl group, oxy A group or a carbonyl group, R ⁵ , R ⁶ and R ⁷ each independently represent a hydrogen atom, a hydroxyl group, a methoxy group or a halogen-substituted methyl group.

ただし、式（２ａ）中、Ｌ^３は、ハロゲン置換されていてもよい炭素数１〜３の２価の脂肪族炭化水素基、スルホニル基、オキシ基、カルボニル基又は単結合を示す。

However, in the formula (2a), L ³ represents a C 1-3 divalent aliphatic hydrocarbon group, sulfonyl group, oxy group, carbonyl group or single bond which may be halogen-substituted.

  Specific examples of the diamine compound having a saturated hydrocarbon group as represented by the above formulas (1a) and (1b) include the following compounds. That is, for example, 2,2-bis [4- (4-aminocyclohexyloxy) cyclohexyl] propane, bis [4- (3-aminocyclohexyloxy) cyclohexyl] sulfone, bis [4- (4-aminocyclohexyloxy) cyclohexyl ] Sulfone, 2,2-bis [4- (4-aminocyclohexyloxy) cyclohexyl] hexafluoropropane, bis [4- (4-aminocyclohexyloxy) cyclohexyl] methane, 4,4′-bis (4-aminocyclohexyl) Oxy) dicyclohexyl, bis [4- (4-aminocyclohexyloxy) cyclohexyl] ether, bis [4- (4-aminocyclohexyloxy) cyclohexyl] ketone, 1,3-bis (4-aminocyclohexyloxy) benzene, 1, 4-bi (4-aminocyclohexyloxy) benzene, 2,2′-dimethylbicyclohexyl-4,4′-diamine, 2,2′-bis (trifluoromethyl) dicyclohexyl-4,4′-diamine, 2,6,2 ', 6'-tetramethyl-4,4'-diamine, 5,5'-dimethyl-2,2'-sulfonyldicyclohexyl-4,4'-diamine, 3,3'-dihydroxydicyclohexyl-4,4'- Diamine, (4,4'-diamino) dicyclohexyl ether, (4,4'-diamino) dicyclohexylsulfone, (4,4'-diaminocyclohexyl) ketone, (3,3'-diamino) benzophenone, (4,4 ' -Diamino) dicyclohexylmethane, (4,4'-diamino) dicyclohexyl ether, (3,3'-diamino) di Black hexyl ether, (4,4'-diamino) dicyclohexylmethane, (3,3'-diamino) dicyclohexylmethane ether, 2,2-bis (4-aminocyclohexyl) propane and the like. A diamine compound may be used individually by 1 type in these compounds, and may be used in combination of 2 or more type. In the production of the polyamideimide of the present embodiment, as will be described later, other diamine compounds, that is, diamine compounds having no saturated hydrocarbon group may be used in combination.

  A diamine compound having a saturated hydrocarbon group can be easily obtained, for example, by subjecting an aromatic diamine compound having an aromatic ring structure corresponding to the saturated hydrocarbon group to hydrogen reduction. Examples of such aromatic diamine compounds include 2,2-bis [4- (4-aminophenoxy) phenyl] propane (hereinafter referred to as “BAPP”), bis [4- (3-aminophenoxy). ) Phenyl] sulfone, bis [4- (4-aminophenoxy) phenyl] sulfone, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, bis [4- (4-aminophenoxy) phenyl ] Methane, 4,4′-bis (4-aminophenoxy) biphenyl, bis [4- (4-aminophenoxy) phenyl] ether, bis [4- (4-aminophenoxy) phenyl] ketone, 1,3-bis (4-Aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, 2,2′-dimethylbiphenyl-4, 4 ′ Diamine, 2,2′-bis (trifluoromethyl) biphenyl-4,4′-diamine, 2,6,2 ′, 6′-tetramethyl-4,4′-diamine, 5,5′-dimethyl-2 2′-sulfonylbiphenyl-4, 4′-diamine, 3,3′-dihydroxybiphenyl-4, 4′-diamine, (4,4′-diamino) diphenyl ether, (4,4′-diamino) diphenylsulfone, (4,4′-diamino) benzophenone, (3,3′-diamino) benzophenone, (4,4′-diamino) diphenylmethane, (4,4′-diamino) diphenyl ether, (3,3′-diamino) diphenyl ether, etc. Can be illustrated.

  Hydrogen reduction of an aromatic diamine compound can be performed by a general method for reducing an aromatic ring. Examples of this reduction method include Raney nickel catalyst and platinum oxide catalyst (D. Varech et al., Tetrahedron Letter, 26, 61 (1985); RHBaker et al., J. Am. Chem. Soc., 69, 1250 (1947)). Rhodium-aluminum oxide catalyst (JCSircar et al., J. Org. Chem., 30, 3206 (1965); AIMeyers et al., Organic Synthesis Collective Volume VI, 371 (1988); AWBurgstahler, Organic Synthesis Collective Volume V, 591 (1973 AJBriggs, Synthesis, 1988, 66), rhodium oxide-platinum oxide catalyst (S. Nishimura, Bull. Chem. Soc. Jpn., 34, 32 (1961); EJCorey et al., J. Am. Chem. Soc) 101, 1608 (1979)), charcoal-supported rhodium catalyst (K. Chebaane et al., Bull. Soc. Chim. Fr., 1975, 244), sodium borohydride-rhodium chloride catalyst (PG Gassman et al., Organic Synthesis Collective Volume VI, 581 (1988); PG Gassman et al., Organic Synthesis Collective Volume VI, 601 (1988)), and the like.

  When the polyamideimide as component (C) is obtained using a diamine compound having a saturated hydrocarbon group as described above, the main chain of the polyamideimide contains a structural unit composed of saturated hydrocarbons. It becomes like this. Such a polyamideimide has an extremely high water absorption resistance or water repellency compared to a conventional polyamideimide due to such a structural unit comprising a saturated hydrocarbon. And according to the conductor-clad laminate 1 using the cured product of a curable resin composition containing a polyamideimide having a structural unit made of saturated hydrocarbon for the adhesive layer 4, for example, a resin composition containing a polyamideimide having an aromatic ring Compared to the case of using an object, when a metal-clad laminate is manufactured, it is possible to greatly suppress a decrease in adhesion between the conductor layer (conductor foil) and the insulating layer during moisture absorption. Become. Such an effect is particularly prominent when a diamine compound having an alicyclic saturated hydrocarbon group is used as the diamine compound having a saturated hydrocarbon group.

  (C) Polyamideimide which is a component may further add a diamine compound other than the diamine compound having an alicyclic saturated hydrocarbon group in the production stage. If it carries out like this, structural units other than the structure which consists of saturated hydrocarbons will be introduce | transduced in the obtained polyamideimide, and also it will become easy to obtain the desired characteristic.

ここで式（３）中、Ｌ^４はメチレン基、スルホニル基、オキソ基、カルボニル基又は単結合を示し、Ｒ^８及びＲ^９は、それぞれ独立に、水素原子、アルキル基又は置換基を有していてもよいフェニル基を示し、ｋは１〜５０の整数を示す。 Examples of the diamine compound other than the diamine compound having a saturated hydrocarbon group include compounds represented by the following general formula (3).

Here, in formula (3), L ⁴ represents a methylene group, a sulfonyl group, an oxo group, a carbonyl group or a single bond, and R ⁸ and R ⁹ each independently have a hydrogen atom, an alkyl group or a substituent. And k represents an integer of 1 to 50.

In the diamine compound represented by the above formula (3), R ⁸ and R ⁹ are each independently a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or a phenyl group which may have a substituent. Preferably there is. Examples of the substituent that may be bonded to the phenyl group include an alkyl group having 1 to 3 carbon atoms and a halogen atom. In the diamine compound represented by the general formula (3), L ⁴ is particularly preferably an oxy group from the viewpoint of achieving both a low elastic modulus and a high Tg. Specific examples of such a diamine compound include Jeffamine D-400 and Jeffamine D-2000 (manufactured by Sun Techno Chemical Co., Ltd., trade name).

  An aromatic diamine having an aromatic ring is also suitable as a diamine compound to be combined with a diamine having a saturated hydrocarbon group. As the aromatic diamine, a compound in which two amino groups are directly bonded to an aromatic ring, or two or more aromatic rings are bonded directly or via a specific group, at least of these aromatic rings A compound in which an amino group is bonded to each of the two is exemplified, and the compound is not particularly limited as long as it has such a structure.

As the aromatic diamine compound, for example, a compound represented by the following general formula (4a) or (4b) is preferable.

In the formulas (4a) and (4b), L ⁵ is an optionally halogenated divalent aliphatic hydrocarbon group having 1 to 3 carbon atoms, a sulfonyl group, an oxy group, a carbonyl group, a single bond, or A divalent group represented by the formula (5a) or (5b), wherein L ⁶ is a halogenated halogenated divalent aliphatic hydrocarbon group having 1 to 3 carbon atoms, a sulfonyl group, an oxy group, or R ¹⁰ , R ¹¹ and R ¹² each independently represent a hydrogen atom, a hydroxyl group, a methoxy group or a halogen-substituted methyl group. In the following formula (5a), L ⁷ represents a C 1-3 divalent aliphatic hydrocarbon group, a sulfonyl group, an oxy group, a carbonyl group or a single bond which may be halogen-substituted.

  Specific examples of the aromatic diamine include 2,2-bis [4- (4-aminophenoxy) phenyl] propane (BAPP), bis [4- (3-aminophenoxy) phenyl] sulfone, and bis [4- (4-aminophenoxy) phenyl] sulfone, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, bis [4- (4-aminophenoxy) phenyl] methane, 4,4′-bis (4-aminophenoxy) biphenyl, bis [4- (4-aminophenoxy) phenyl] ether, bis [4- (4-aminophenoxy) phenyl] ketone, 1,3-bis (4-aminophenoxy) benzene, 1 , 4-bis (4-aminophenoxy) benzene, 2,2′-dimethylbiphenyl-4,4′-diamine, 2,2′-bis (trif Oromethyl) biphenyl-4,4′-diamine, 2,6,2 ′, 6′-tetramethyl-4,4′-diamine, 5,5′-dimethyl-2,2′-sulfonylbiphenyl-4,4 ′ -Diamine, 3,3'-dihydroxybiphenyl-4,4'-diamine, (4,4'-diamino) diphenyl ether, (4,4'-diamino) diphenylsulfone, (4,4'-diamino) benzophenone, 3,3′-diamino) benzophenone, (4,4′-diamino) diphenylmethane, (4,4′-diamino) diphenyl ether, (3,3′-diamino) diphenyl ether, and the like. An aromatic diamine compound may be used individually by 1 type in the compound mentioned above, and may be used in combination of 2 or more type.

  By using these aromatic diamines in combination, an aromatic ring structure is introduced into the polyamideimide in addition to the structural units composed of saturated hydrocarbons. The curable resin composition containing such polyamideimide can further improve the Tg of the cured product (adhesive layer 4), and can further improve the heat resistance.

Furthermore, as a diamine compound used in combination with a diamine compound having a saturated hydrocarbon group, a siloxane diamine represented by the following general formula (6) is suitable.

In the formula (6), R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ (hereinafter referred to as “R ^{13 to} R ¹⁸ ”) each independently represent 1 to 1 carbon atoms. It is preferable that it is the phenyl group which may have 3 alkyl groups or a substituent. The substituent that may be bonded to the phenyl group is preferably an alkyl group having 1 to 3 carbon atoms or a halogen atom. R ¹⁹ and R ²⁰ are each independently preferably an alkylene group having 1 to 6 carbon atoms or an arylene group which may have a substituent. As this arylene group, a phenylene group which may have a substituent or a naphthalene group which may have a substituent is preferable. Furthermore, as a substituent which may be couple | bonded with this arylene group, a C1-C3 alkyl group or a halogen atom is preferable. Furthermore, in Formula (6), a and b are integers of 1-15, respectively.

As such a siloxane diamine, a compound in which R ^{13 to} R ¹⁸ are methyl groups, that is, a compound having a structure in which amino groups are bonded to both ends of dimethylsiloxane is particularly preferable. As the siloxane diamine, one type of compound may be used alone, or two or more types of compounds may be used in combination.

  Specific examples of the siloxane diamine represented by the general formula (6) include silicone oil X-22-161AS (amine equivalent 450), X-22-161A (amine equivalent 840), X-22-161B ( Amine equivalent 1500), X-22-9409 (amine equivalent 700), X-22-1660B-3 (amine equivalent 2200) (above, manufactured by Shin-Etsu Chemical Co., Ltd., trade name), BY16-853 (amine equivalent 650), What is commercially available as BY16-853B (amine equivalent 2200) (above, manufactured by Toray Dow Corning Silicone Co., Ltd.) is suitable.

  By using the siloxane diamine described above as the diamine compound, the polyamideimide as the component (C) has a siloxane structure in the main chain. Further, the curable resin composition containing such a polyamideimide having a siloxane structure can form a cured product that is excellent in flexibility and hardly generates swelling under high temperature conditions. The durability and heat resistance of a printed wiring board or the like obtained using the conductor-clad laminate 1 can be further improved.

  In the production of a polyamideimide having a structural unit composed of a saturated hydrocarbon, first, a diamine compound containing at least a diamine compound having a saturated hydrocarbon group is prepared as a diamine compound. Subsequently, these diamine compounds are reacted with trimellitic anhydride. At this time, a reaction occurs between the amino group of the diamine compound and the carboxyl group or the anhydrous carboxyl group of trimellitic anhydride to produce an amide group. In such a reaction, it is particularly preferable to cause a reaction between the amino group of the diamine compound and the anhydrous carboxyl group of trimellitic anhydride.

  This reaction is preferably performed at 70 to 100 ° C. by dissolving or dispersing the diamine compound and trimellitic anhydride in an aprotic polar solvent. Examples of the aprotic polar solvent include N-methyl-2-pyrrolidone (NMP), γ-butyrolactone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, sulfolane, and cyclohexanone. Of these, NMP is particularly preferable. These aprotic polar solvents may be used alone or in combination of two or more.

  The aprotic polar solvent is preferably an amount such that the solid content is 10 to 70% by mass with respect to the total mass of the aprotic polar solvent, the diamine compound and trimellitic anhydride, and is 20 to 60% by mass. Is more preferable. When the solid content in the solution is less than 10% by mass, the amount of the solvent used is too large and tends to be industrially disadvantageous. On the other hand, when it exceeds 70% by mass, the solubility of trimellitic anhydride is lowered, and it tends to be difficult to perform a sufficient reaction.

  Next, an aromatic hydrocarbon which can be azeotroped with water is added to the solution after the above reaction, and further reacted at 150 to 200 ° C. Thereby, a dehydration ring-closing reaction occurs between the adjacent carboxyl group and amide group, and as a result, an imide group-containing dicarboxylic acid is obtained. Here, examples of the aromatic hydrocarbon that can be azeotroped with water include toluene, benzene, xylene, and ethylbenzene. Of these, toluene is preferable. The aromatic hydrocarbon is preferably added in an amount corresponding to 10 to 50 parts by mass with respect to 100 parts by mass of the aprotic polar solvent. When the addition amount of the aromatic hydrocarbon is less than 10 parts by mass with respect to 100 parts by mass of the aprotic polar solvent, the water removal effect tends to be insufficient, and generation of an imide group-containing dicarboxylic acid The amount may be reduced. On the other hand, if the amount exceeds 50 parts by mass, the reaction temperature in the solution decreases, and the amount of imide group-containing dicarboxylic acid produced tends to decrease.

  During this dehydration ring closure reaction, the aromatic hydrocarbon in the solution is distilled off together with water, so that the amount of the aromatic hydrocarbon in the reaction solution may be less than the above-mentioned preferred range. Thus, for example, by performing operations such as distilling water and aromatic hydrocarbons into a moisture determination receiver with a cock, separating the aromatic hydrocarbons, and then returning them to the reaction solution. The amount of the group hydrocarbon may be kept at a certain ratio. In addition, after completion | finish of a spin-drying | dehydration ring-closing reaction, it is preferable to remove the aromatic hydrocarbon which can azeotrope with water, keeping the temperature of a solution at about 150-200 degreeC.

The imide group-containing dicarboxylic acid obtained by the reaction so far has, for example, a structure represented by the following general formula (7).

In the formula (7), L ⁸ is a residue obtained by removing the amino group of the diamine compound represented by the general formula (1a), (1b), (3), (4a), (4b) or (6). Indicates. The imide-containing dicarboxylic acid, various compounds having the L ⁸ of structure corresponding to the diamine compound used as the starting material can be obtained.

  Examples of a method for synthesizing polyamideimide using the imide group-containing dicarboxylic acid thus obtained include the following methods. That is, first, as the first method, there is a method in which an imide group-containing dicarboxylic acid as described above is derived into an acid halide and then copolymerized with the diamine compound as described above.

  The imide group-containing dicarboxylic acid is easily derived into an acid halide by reaction with thionyl chloride, phosphorus trichloride, phosphorus pentachloride, or dichloromethyl methyl ether. The imide group-containing dicarboxylic acid halide thus obtained can be easily copolymerized with a diamine compound at room temperature or under heating conditions.

  The second method includes a method in which an imide group-containing dicarboxylic acid is copolymerized with the diamine compound as described above in the presence of a condensing agent. In such a reaction, a general condensing agent that forms an amide bond can be used as the condensing agent. Among these, it is preferable to use dicyclohexylcarbodiimide, diisopropylcarbodiimide or N-ethyl-N′-3-dimethylaminopropylcarbodiimide alone, or to use these in combination with N-hydroxysuccinimide or 1-hydroxybenzotriazole.

  As a third method, a method of reacting an imide group-containing dicarboxylic acid with a diisocyanate can be mentioned. When going through such a reaction, the ratio of the diamine compound and trimellitic anhydride, which are raw materials of the imide group-containing dicarboxylic acid, and the diisocyanate is preferably set as follows. That is, (diamine compound: trimellitic anhydride: diisocyanate) is in a molar ratio of 1.0: (2.0 to 2.2): (1.0 to 1.5). Preferably, 1.0: (2.0 to 2.2) :( 1.0 to 1.3) is more preferable. By adjusting to such a molar ratio, it is possible to obtain a polyamideimide having a higher molecular weight and advantageous for film formation.

Examples of the diisocyanate used in the third method include compounds represented by the following general formula (8).

In formula (8), L ⁹ is a divalent organic group or divalent aliphatic hydrocarbon group having one or more aromatic rings. In particular, it is selected from the group consisting of a group represented by the following formula (9a), a group represented by the following formula (9b), a tolylene group, a naphthylene group, a hexamethylene group, and a 2,2,4-trimethylhexamethylene group. It is preferably at least one group.

  Examples of the diisocyanate represented by the general formula (8) include aliphatic diisocyanates and aromatic diisocyanates, and aromatic diisocyanates are preferable, and it is particularly preferable to use both in combination. Examples of aromatic diisocyanates include 4,4′-diphenylmethane diisocyanate (MDI), 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, naphthalene-1,5-diisocyanate, and 2,4-tolylene dimer. It can be illustrated. Of these, MDI is particularly preferable. By using MDI as the aromatic diisocyanate, the flexibility of the resulting polyamideimide can be improved and the crystallinity can be reduced. As a result, the film-formability of polyamideimide can be improved. On the other hand, examples of the aliphatic diisocyanate include hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, and isophorone diisocyanate.

  When the aromatic diisocyanate and the aliphatic diisocyanate are used in combination, it is preferable to add the aliphatic diisocyanate in an amount of about 5 to 10 parts by mole with respect to 100 parts by mole of the aromatic diisocyanate. Thereby, the heat resistance of the polyamideimide obtained can be further improved.

  The reaction of the imide group-containing dicarboxylic acid and the diisocyanate in the third method can be performed by adding the diisocyanate to a solution containing the imide group-containing dicarboxylic acid and reacting at a reaction temperature of 130 to 200 ° C. Moreover, you may perform this reaction using a basic catalyst. In this case, the reaction temperature is preferably 70 to 180 ° C, more preferably 120 to 150 ° C. When this reaction is performed in the presence of a basic catalyst, the reaction can proceed at a lower temperature than when the reaction is performed in the absence of a basic catalyst. The progress of side reactions such as reactions can be suppressed. As a result, a higher molecular weight polyamideimide compound can be obtained.

  Examples of the basic catalyst include trialkylamines such as trimethylamine, triethylamine, tripropylamine, tri (2-ethylhexyl) amine, and trioctylamine. Among these, triethylamine is particularly preferable because it is a suitable basic catalyst that can promote the above-described reaction and is easily removed from the system after the reaction.

Examples of the polyamideimide obtained by the various methods described above include those having a structural unit represented by the following general formula (10). In the following formulas (10), ^{L 8} and ^{L 9} has the same meaning as ^{L 8} and ^{L 9} above.

  The curable resin composition in a preferred embodiment contains the components (A) to (C) as described above. And in such a curable resin composition, it is preferable that (A)-(C) component is contained in the mixture ratio which satisfy | fills the conditions as shown below.

  First, the blending ratio of the component (B) in the curable resin composition is preferably 0.5 to 200 parts by mass and more preferably 10 to 150 parts by mass with respect to 100 parts by mass of the component (A). preferable. When the blending ratio of the component (B) is less than 0.5 parts by mass, the toughness of the adhesive layer and the adhesiveness to the conductor layer (conductor foil) in the conductor-clad laminate 1 and the printed wiring board obtained using the same. Tend to decrease. On the other hand, if it exceeds 200 parts by mass, the thermosetting property of the adhesive layer 4 is lowered, and the reactivity between the adhesive layer and the insulating resin layer is lowered, so that the conductor-clad laminate 1 or a printed wiring board as described later is used. When the film is formed, the heat resistance, chemical resistance and breaking strength in the vicinity of the adhesive layer itself or the interface between the adhesive layer and the insulating resin layer tend to be lowered.

  Moreover, it is preferable that the mixture ratio of (C) component shall be 0.5-500 mass parts with respect to a total of 100 mass parts of (A) component and (B) component, and shall be 1-400 mass parts. Is more preferable, and it is still more preferable to set it as 10-400 mass parts. When the blending ratio of the component (C) is less than 0.5 parts by mass, in the conductor-clad laminate 1 or a printed wiring board obtained using the same, the toughness of the adhesive layer and the conductor layer (conductor foil) There is a tendency for the adhesiveness to decrease. Moreover, when it exceeds 500 mass parts, it exists in the tendency for the heat resistance of the adhesive layer itself or the interface vicinity of an adhesive layer and an insulating resin layer, chemical resistance, and breaking strength to fall.

  The curable resin composition that is cured to become the adhesive layer 4 may further contain a desired component as necessary in addition to the components (A) to (C) described above. As components other than the components (A) to (C), first, curing acceleration having a catalytic function for promoting the reaction between the polyfunctional epoxy resin as the component (A) and the polyfunctional phenol resin as the component (B). Agents. Although it does not restrict | limit especially as a hardening accelerator, For example, an amine compound, an imidazole compound, an organic phosphorus compound, an alkali metal compound, an alkaline-earth metal compound, a quaternary ammonium salt etc. are mentioned. As a hardening accelerator, 1 type may be used independently and 2 or more types may be used in combination.

  The blending ratio of the curing accelerator in the curable resin composition is preferably determined according to the blending ratio of the component (A). Specifically, it is preferable to set it as 0.05-10 mass parts with respect to 100 mass parts of (A) component. When a curing accelerator is blended within this range, a good reaction rate between the component (A) and the component (B) is obtained, and the curable resin composition that is cured to become the adhesive layer 4 is reactive and cured. It will become even more excellent. As a result, the adhesive layer 4 has more excellent chemical resistance, heat resistance and moisture heat resistance.

  Further, the curable resin composition has various heat-resistant properties such as crosslinked rubber particles, flame retardants, fillers, coupling agents, etc. depending on the desired properties, and heat resistance by the adhesive layer 4 when a printed wiring board is formed. It may be included to such an extent that properties such as property, adhesiveness and moisture absorption resistance are not deteriorated.

  The crosslinked rubber particles described above are preferably at least one selected from acrylonitrile butadiene rubber particles, carboxylic acid-modified acrylonitrile butadiene rubber particles, and core-shell particles of butadiene rubber-acrylic resin.

  Here, the acrylonitrile butadiene rubber particles are particles obtained by copolymerizing acrylonitrile and butadiene and partially crosslinking in the copolymerization stage. The carboxylic acid-modified acrylonitrile butadiene rubber particles are obtained by copolymerizing together carboxylic acids such as acrylic acid and methacrylic acid in the above copolymerization. Further, the core-shell particles of butadiene rubber-acrylic resin are obtained by a two-stage polymerization method in which butadiene particles are polymerized by emulsion polymerization, and a monomer such as acrylic acid ester or acrylic acid is further added to continue polymerization. The size of these crosslinked rubber particles is preferably a primary average particle diameter of 50 nm to 1 μm. As the crosslinked rubber particles, those described above may be added alone or in combination of two or more.

  More specific examples of such crosslinked rubber particles include, for example, XER-91 manufactured by Nippon Synthetic Rubber Co., Ltd. as carboxylic acid-modified acrylonitrile butadiene rubber particles. Examples of the core-shell particles of butadiene rubber-acrylic resin include EXL-2655 manufactured by Kureha Chemical Industry Co., Ltd. and AC-3832 manufactured by Takeda Pharmaceutical Company Limited.

  In the curable resin composition, the blending ratio of the crosslinked rubber particles is preferably 0.5 to 100 parts by mass with respect to 100 parts by mass in total of the component (A) and the component (B), and 1 to 50 parts by mass. It is more preferable. When the blending ratio of the crosslinked rubber particles is less than 0.5 parts by mass, in the conductor-clad laminate 1 and a printed wiring board obtained using the same, the toughness of the adhesive layer, the adhesive layer and the conductor layer (conductor foil) There is a tendency for the adhesiveness to decrease. On the other hand, when it exceeds 100 parts by mass, the heat resistance, chemical resistance, and breaking strength in the vicinity of the adhesive layer itself or the interface between the adhesive layer and the insulating resin layer tend to be reduced. In addition, when several types of component is included as a crosslinked rubber particle, it is preferable that those sum totals satisfy | fill the compounding ratio mentioned above.

  Although it does not specifically limit as a flame retardant, Flame retardants, such as a bromine type, a phosphorus type, and a metal hydroxide, are suitable. More specifically, brominated flame retardants include brominated epoxy resins such as brominated bisphenol A type epoxy resin and brominated phenol novolac type epoxy resin, hexabromobenzene, pentabromotoluene, ethylenebis (pentabromophenyl) , Ethylenebistetrabromophthalimide, 1,2-dibromo-4- (1,2-dibromoethyl) cyclohexane, tetrabromocyclooctane, hexabromocyclododecane, bis (tribromophenoxy) ethane, brominated polyphenylene ether, brominated Brominated flame retardants such as polystyrene, 2,4,6-tris (tribromophenoxy) -1,3,5-triazine, tribromophenyl maleimide, tribromophenyl acrylate, tribromophenyl methacrylate, tetrabromobi Phenol A type dimethacrylate, pentabromobenzyl acrylate, brominated reactive flame retardant containing an unsaturated double bond of the brominated styrene.

  Phosphorus flame retardants include aromatics such as triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, cresyl diphenyl phosphate, cresyl di-2, 6-xylenyl phosphate, resorcinol bis (diphenyl phosphate) Phosphoric acid esters, phosphonic acid esters such as diphenyl phenylphosphonate, diallyl phenylphosphonate, bis (1-butenyl) phenylphosphonate, phenyl diphenylphosphinate, methyl diphenylphosphinate, 9,10-dihydro-9-oxa- Phosphinic acid esters such as 10-phosphaphenanthrene-10-oxide derivatives, phosphazene compounds such as bis (2-allylphenoxy) phosphazene and dicresyl phosphazene, melamine phosphate, melamine pyrophosphate, Li Lin melamine, melam polyphosphate, ammonium polyphosphate, phosphorus-based flame retardant of red phosphorus and the like. Further, examples of the metal hydroxide flame retardant include magnesium hydroxide and aluminum hydroxide. These flame retardants may be used individually by 1 type, and may be used in combination of multiple types.

  When the flame retardant is added, the blending ratio is not particularly limited, but is preferably 5 to 150 parts by mass with respect to 100 parts by mass of the total amount of the component (A) and the component (B), and 5 to 80 It is more preferable to set it as a mass part, and it is still more preferable to set it as 5-60 mass parts. When the blending ratio of the flame retardant is less than 5 parts by mass, the flame resistance of the pre-curing adhesive layer and the adhesive layer 4 tends to be insufficient. On the other hand, when it exceeds 100 parts by mass, the heat resistance of the adhesive layer 4 tends to decrease.

  Moreover, it does not specifically limit as a filler which is an additive, However, An inorganic filler is suitable. Examples of the inorganic filler include alumina, titanium oxide, mica, silica, beryllia, barium titanate, potassium titanate, strontium titanate, calcium titanate, aluminum carbonate, magnesium hydroxide, aluminum hydroxide, aluminum silicate, Examples thereof include calcium carbonate, calcium silicate, magnesium silicate, silicon nitride, boron nitride, clay such as calcined clay, talc, aluminum borate, aluminum borate, silicon carbide and the like.

  These fillers may be used individually by 1 type, and may be used in combination of 2 or more type. Moreover, there is no restriction | limiting in particular about the shape of a filler, and a particle size, However, When a particle size is 0.01-50 micrometers, it is more preferable that it is 0.1-15 micrometers. The blending ratio of the filler in the curable resin composition is, for example, preferably 1 to 1000 parts by mass and 1 to 800 parts by mass with respect to 100 parts by mass of the total amount of the component (A) and the component (B). More preferably.

  Furthermore, although it does not specifically limit as a coupling agent, For example, a silane coupling agent, a titanate coupling agent, etc. are mentioned. Examples of the silane coupling agent include carbon functional silane. Specifically, epoxy group-containing silanes such as 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyl (methyl) dimethoxysilane, 2- (2,3-epoxycyclohexyl) ethyltrimethoxysilane; Amino group-containing silanes such as aminopropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyl (methyl) dimethoxysilane; Cationic silanes such as (trimethoxylyl) propyltetramethylammonium chloride; vinyl group-containing silanes such as vinyltriethoxysilane; acrylic group-containing silanes such as 3-methacryloxypropyltrimethoxysilane; 3-mercaptopropyltrimethoxysilane Of mercapto group-containing silanes It is below. On the other hand, examples of titanate coupling agents include alkyl titanates such as titanium propoxide and titanium butoxide. As these coupling agents, one kind may be used alone, or two or more kinds may be used in combination.

  The blending ratio of the coupling agent in the curable resin composition is not particularly limited, but is preferably 0.05 to 20 parts by mass with respect to 100 parts by mass of the total amount of the component (A) and the component (B). It is more preferable in it being 0.1-10 mass parts.

  And the curable resin composition containing each component mentioned above prepares by mix | blending (A) component, (B) component, (C) component, and another additive component by a well-known method, and mixing. Can do.

[Method for producing conductor-clad laminate]
Next, the manufacturing method of the said conductor clad laminated board 1 is demonstrated.

  First, the curable resin composition described above is prepared, and the varnish prepared by dissolving or dispersing it in a solvent is applied to the M surface of the conductor foil as described above, and then dried and cured. A pre-adhesive layer is used. Thus, a conductor foil with an adhesive layer formed by laminating the conductor foil to be the conductor layer 6 and the pre-curing adhesive layer to be cured to be the adhesive layer 4 is obtained. At this time, the curable resin composition may be semi-cured (B-staged).

  The curable resin composition and its varnish can be applied by a known method, for example, using a kiss coater, a roll coater, a comma coater, or the like. Moreover, drying can be implemented by the method of processing in a heat drying oven etc. at the temperature of 70-250 degreeC, for example, Preferably it is 100-200 degreeC for 1 to 30 minutes, Preferably it is 3 to 15 minutes. When a solvent is used to dissolve the curable resin composition, the drying temperature is preferably equal to or higher than the temperature at which the solvent can be volatilized.

  The solvent used for varnishing the curable resin composition is not particularly limited. For example, alcohols such as methanol, ethanol, butanol, ethyl cellosolve, butyl cellosolve, ethylene glycol monomethyl ether, carbitol, butyl carbitol, etc. Ethers, acetone, methyl ethyl ketone, methyl isobutyl ketone, ketones such as cyclohexanone, aromatic hydrocarbons such as toluene, xylene, mesitylene, esters such as methoxyethyl acetate, ethoxyethyl acetate, butoxyethyl acetate, ethyl acetate, Examples thereof include solvents such as nitrogen-containing compounds such as N, N-dimethylformamide, N, N-dimethylacetamide and N-methyl-2-pyrrolidone. In varnishing, only one solvent may be used alone, or two or more solvents may be used in combination.

  Among these solvents, when nitrogen-containing compounds and ketones are used in combination, the blending ratio is preferably such that the ketones are 1 to 500 parts by mass with respect to 100 parts by mass of nitrogen-containing compounds. More preferably, it is 300 parts by mass, and even more preferably 5 to 250 parts by mass.

  In addition, when the curable resin composition is varnished, it is preferable to adjust the amount of the solvent so that the solid content (nonvolatile content) concentration in the varnish is 5 to 80% by mass. When producing a conductor foil with an adhesive layer, the solid content concentration and varnish viscosity can be adjusted by appropriately adjusting the amount of solvent so that a pre-curing adhesive layer having a preferred film thickness as described above can be obtained. It becomes easy.

  In addition, a prepreg for forming the insulating layer 2 is prepared simultaneously with the preparation of the conductor film with the adhesive layer. Examples of the prepreg include those prepared by a known method such as impregnating a reinforcing fiber such as glass fiber or organic fiber with the above-described insulating resin and semi-curing the resin.

  Next, a plurality of the prepregs are stacked to form an insulating resin film. Then, the conductive foil with an adhesive layer is stacked on one surface of the insulating resin film so that the adhesive layer before curing is in contact with the insulating resin film. Then, the conductor clad laminated board 1 is obtained by heating and / or pressurizing these. By this heating and pressurization, the insulating resin in the insulating resin film is cured, and the curable resin composition constituting the pre-curing adhesive layer is cured. As a result, the insulating layer 2 is formed from the insulating resin film, and the adhesive layer 4 is formed from the pre-curing adhesive layer.

  The heating is preferably performed at a temperature of 150 to 250 ° C., the pressing is preferably performed at a pressure of 0.5 to 10.0 MPa, and the heating and pressing time is 0.5 to 10 hours. preferable. This heating and pressurization can be performed simultaneously by using, for example, a vacuum press. As a result, the curing of the pre-curing adhesive layer and the insulating resin film sufficiently proceeds, and the adhesive layer 4 has excellent adhesion between the conductor layer 6 and the insulating layer 2, and also has chemical resistance, heat resistance and A conductor-clad laminate 1 having excellent moisture and heat resistance is obtained.

[Printed wiring board]
Next, a printed wiring board according to a preferred embodiment of the present invention will be described with reference to FIG. FIG. 2 is a cross-sectional view showing a printed wiring board according to a preferred embodiment.

  The printed wiring board 10 has a configuration including an insulating layer 12, an adhesive layer 14, and a circuit pattern 16 in this order. The insulating layer 12, the adhesive layer 14, and the circuit pattern 16 are made of the same material as the insulating layer 2, the adhesive layer 4 and the conductor layer 6 in the conductor-clad laminate 1, respectively. The wiring board 10 having such a configuration can be manufactured, for example, by processing the conductor layer 6 in the above-described conductor-clad laminate 1 into a desired circuit pattern by applying a known etching method. .

[Multilayer wiring board]
Next, a multilayer wiring board according to a preferred embodiment of the present invention will be described with reference to FIG. FIG. 3 is a schematic diagram showing a cross-sectional structure of the multilayer wiring board of the present embodiment.

  In the multilayer wiring board 20, a set of wiring boards having an insulating layer 22, an adhesive layer 24, an inner layer circuit pattern 26, an interlayer insulating layer 28, and an outer layer circuit pattern 30 in this order are laminated so that the insulating layers 22 face each other. Have a structure. In the multilayer wiring board 20, the inner layer circuit pattern 26 and the outer layer circuit pattern 30 are connected by a via hole 32 provided in the interlayer insulating layer 28. Further, the inner layer circuit patterns 26 in a set of wiring boards are connected by a through hole 34.

  In the multilayer wiring board 20, the insulating layer 22, the adhesive layer 24, and the inner circuit pattern 26 are made of the same material as the insulating layer 12, the adhesive layer 24, and the circuit pattern 16 in the printed wiring board 10, respectively. That is, the multilayer wiring board 20 includes the above-described printed wiring board 10 as the core substrate 40. In addition, as the interlayer insulating layer 28, a layer made of a known insulating resin material (for example, a resin material included in the insulating layer 12 in the printed wiring board 10), or a predetermined material in the insulating resin material is used. Examples thereof include a layer made of a prepreg on which a reinforcing substrate is arranged.

  Further, the outer layer circuit pattern 30 is made of the same conductive material as the inner layer circuit pattern 26. Furthermore, the via hole 32 and the through hole 34 are formed by filling holes provided in the insulating layer 22, the adhesive layer 24, the interlayer insulating layer 28, and the like with a predetermined conductive material. By the via hole 32 or the through hole 34, the inner layer circuit pattern 26 and the outer layer circuit pattern 30 or the inner layer circuit patterns 26 are electrically connected to each other at a predetermined portion.

  The multilayer wiring board 20 having such a configuration can be manufactured by the following method. That is, first, a set of printed wiring boards 10 to be the core substrate 40 is prepared and stacked so that the insulating layers 22 face each other. This is subjected to drilling, metal plating or the like as necessary to form a through hole 34. Next, a predetermined number of prepregs or the like that should form the interlayer insulating layer 28 are stacked on the circuit pattern 16 (inner layer circuit pattern 26) on the printed wiring board 10.

  Then, after making a hole at a desired position in the prepreg, the via hole 32 is formed by filling with a conductive material. Thereafter, the same metal foil as the inner layer circuit pattern 26 is laminated on the prepreg, and these are heat-pressed to be pressure-bonded. Then, the outermost layer metal foil is processed into a desired circuit pattern by a known etching method or the like to form the outer layer circuit pattern 30 to obtain the multilayer wiring board 20.

  Note that the multilayer wiring board of the present invention is not limited to the above-described embodiment as long as at least the core board 40 includes the wiring board of the present invention. For example, an adhesive layer similar to the adhesive layer 24 may be formed between the interlayer insulating layer 28 and the outer layer circuit pattern 30. As a result, the interlayer insulating layer 24 and the outer circuit pattern 30 are firmly bonded via this adhesive layer, so that the multilayer wiring board 20 has not only the inner circuit pattern 26 but also the outer circuit pattern 30. Peeling is extremely difficult to occur.

  As described above, the multilayer wiring board having the adhesive layer between the interlayer insulating layer 28 and the outer layer circuit pattern 30 is, for example, in addition to sequentially forming the interlayer insulating layer 28 and the outer layer circuit pattern 30 as described above. It can also be obtained by laminating the resin-coated metal foil used for manufacturing the wiring board 10 on the core substrate 40. Such a multilayer wiring board 20 can also be manufactured by laminating the wiring board 10 having the same or different circuit pattern 16 on the core substrate 40.

  Furthermore, the multilayer wiring board 20 is not limited to the illustrated number of layers, and may have a desired number of layers. In such a multilayer wiring board 20, the interlayer insulating layers 28 and the outer layer circuit patterns 30 are alternately laminated on both sides of the core substrate 40 according to the desired number of laminations, or the wiring board 10 is arranged in a desired number of layers. It can manufacture by laminating | stacking so that it may become.

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to the above embodiment. The present invention can be variously modified without departing from the gist thereof.

  For example, in another embodiment of the present invention, the conductor-clad laminate is not limited to the above-described preferred embodiment. For example, a layer formed by integrating an insulating layer and an adhesive layer is sandwiched between a pair of conductor layers. You may have the structure comprised. Even with such a conductor-clad laminate, it is advantageous for producing a printed wiring board capable of sufficiently suppressing transmission loss in a high frequency band, and the adhesiveness between the insulating layer and the conductor layer is excellent. It will be excellent enough.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples.

[Synthesis of Polyamideimide]
(Synthesis Example 1)
First, in a 1 L separable flask equipped with a Dean-Stark reflux condenser, a thermometer, and a stirrer, (4,4′-diamino) dicyclohexylmethane (Wandamine HM (as diamine compound A having a saturated alicyclic hydrocarbon group) was added. WHM), manufactured by Shin Nippon Chemical Co., Ltd., trade name) 45 mmol, reactive silicone oil as siloxane diamine compound B (X-22-161-B, manufactured by Shin-Etsu Chemical Co., Ltd., amine equivalent: 1500, trade name) 5 mmol, anhydrous tri 105 mmol of merit acid (TMA) and 85 g of N-methyl-2-pyrrolidone (NMP) as an aprotic polar solvent were added, and the temperature in the flask was set at 80 ° C. and stirred for 30 minutes.

  After completion of the stirring, 100 mL of toluene was further added as an aromatic hydrocarbon azeotropic with water, and the temperature in the flask was raised to 160 ° C. and refluxed for about 2 hours. After confirming that the theoretical amount of water was stored in the moisture meter and no water distilling was observed, the temperature in the flask was increased to 190 ° C while removing the water in the meter. The toluene in the reaction solution was removed.

After returning the solution in the flask to room temperature, 60 mmol of 4,4′-diphenylmethane diisocyanate (MDI) was added as a diisocyanate, the temperature in the flask was raised to 190 ° C. and reacted for 2 hours, and then diluted with NMP. Thus, an NMP solution of polyamideimide of Synthesis Example 1 (solid content concentration of 30% by mass) was obtained. It was 34000 when the weight average molecular weight (Mw) of this NMP solution was measured by the gel permeation chromatography.
(Synthesis Example 2)

  First, in a 1 L separable flask equipped with a Dean-Stark reflux condenser, a thermometer, and a stirrer, Jeffamine D-2000 (trade name) manufactured by Sun Techno Chemical Co., Ltd. was used as a diamine compound C having a saturated aliphatic hydrocarbon group. As a diamine compound A having a saturated alicyclic hydrocarbon group, (4,4'-diamino) dicyclohexylmethane (Wandamine HM (WHM), manufactured by Shin Nippon Rika Co., Ltd., trade name) 40 mmol, trimellitic anhydride (TMA) 105 mmol In addition, 150 g of N-methyl-2-pyrrolidone (NMP) was added as an aprotic polar solvent, and the temperature in the flask was set to 80 ° C. and stirred for 30 minutes.

  After completion of the stirring, 100 mL of toluene was further added as an aromatic hydrocarbon azeotropic with water, and the temperature in the flask was raised to 160 ° C. and refluxed for about 2 hours. After confirming that the theoretical amount of water was stored in the moisture meter and no water distilling was observed, the temperature in the flask was increased to 190 ° C while removing the water in the meter. The toluene in the reaction solution was removed.

After returning the solution in the flask to room temperature, 180 mmol of 4,4′-diphenylmethane diisocyanate (MDI) was added as a diisocyanate, the temperature in the flask was raised to 190 ° C. and reacted for 2 hours, and then diluted with NMP. Thus, an NMP solution of polyamideimide of Synthesis Example 2 (solid content concentration of 30% by mass) was obtained. It was 84000 when Mw of this NMP solution was measured by the gel permeation chromatography.
(Synthesis Example 3)

  First, in a 1 L separable flask equipped with a Dean-Stark reflux condenser, a thermometer, and a stirrer, Jeffamine D-2000 (trade name, manufactured by Sun Techno Chemical Co., Ltd.) 30 mmol as a diamine compound C having a saturated aliphatic hydrocarbon group. , (4,4′-diamino) diphenylmethane (DDM) 120 mmol as aromatic diamine compound D, 315 mmol of trimellitic anhydride (TMA), 100 g of N-methyl-2-pyrrolidone (NMP) as an aprotic polar solvent, The temperature in the flask was set to 80 ° C. and stirred for 30 minutes.

  After completion of the stirring, 100 mL of toluene was further added as an aromatic hydrocarbon azeotropic with water, and the temperature in the flask was raised to 160 ° C. and refluxed for about 2 hours. After confirming that the theoretical amount of water was stored in the moisture meter and no water distilling was observed, the temperature in the flask was increased to 190 ° C while removing the water in the meter. The toluene in the reaction solution was removed.

  After returning the solution in the flask to room temperature, 180 mmol of 4,4′-diphenylmethane diisocyanate (MDI) was added as a diisocyanate, the temperature in the flask was raised to 190 ° C. and reacted for 2 hours, and then diluted with NMP. Thus, an NMP solution of polyamideimide of Synthesis Example 3 (solid content concentration of 30% by mass) was obtained. It was 74000 when Mw of this NMP solution was measured by the gel permeation chromatography.

[Preparation of resin varnish for adhesive layer (curable resin composition)]
(Preparation Example 1)
(A) Component cresol novolac type epoxy resin (YDCN-500, manufactured by Tohto Kasei Co., Ltd., trade name) 5.0B, component (B) novolac type phenol resin (MEH7500, manufactured by Meiwa Kasei Co., Ltd., trade name) 3.1 g and 18 g of the NMP solution of polyamideimide obtained in Synthesis Example 1 as the component (C) were blended. Furthermore, after adding 0.025 g of 2-ethyl-4-methylimidazole (2E4MZ, manufactured by Shikoku Kasei Kogyo Co., Ltd.) as a curing accelerator, 28 g of N-methyl-2-pyrrolidone and 13 g of methyl ethyl ketone were blended. Thus, a resin varnish for the adhesive layer of Preparation Example 1 (solid content concentration of about 20% by mass) was prepared.

  In addition, the glass transition temperature (Tg) of the resin composition obtained by hardening | curing resin which added 2E4MZ to YDCN-500 and MEH7500 was 190 degreeC. Here, the glass transition temperature Tg is a value measured by differential scanning calorimetry (DSC) in accordance with JIS-K7121-1987.

(Preparation Example 2)
(A) Phenol novolac epoxy resin (N-770, manufactured by Dainippon Ink & Chemicals, Inc., trade name) (5.0 g) is added to (B) component cresol novolac type phenol resin (KA-1165, Dainippon). Ink Chemical Industries, Ltd., trade name) 3.9 g, 55 g of NMP solution of polyamideimide obtained in Synthesis Example 2 as component (C) was blended. Furthermore, 0.025 g of 2-ethyl-4-methylimidazole (2E4MZ, manufactured by Shikoku Kasei Kogyo Co., Ltd., trade name) was added as a curing accelerator, and then 39 g of N-methyl-2-pyrrolidone and 20 g of methyl ethyl ketone were blended. Thus, a resin varnish for the adhesive layer of Preparation Example 2 (solid content concentration of about 20 mass%) was prepared.

  In addition, the glass transition temperature (Tg) of the resin composition obtained by hardening | curing resin which added 2E4MZ to N-770 and KA-1165 was 190 degreeC.

(Preparation Example 3)
(B) component bisphenol A novolak resin (YLH129, Japan Epoxy Resin Co., Ltd.) to 5.0 g of novolak type epoxy resin (NC-3000H, manufactured by Nippon Kayaku Co., Ltd., trade name) having a biphenyl structure as component (A) Manufactured, trade name) 2.0 g, and 38 g of NMP solution of polyamideimide obtained in Synthesis Example 3 as component (C). Further, 0.025 g of 2-ethyl-4-methylimidazole (2E4MZ, manufactured by Shikoku Kasei Kogyo Co., Ltd., trade name) was added as a curing accelerator, and then 35 g of N-methyl-2-pyrrolidone and 13 g of methyl ethyl ketone were blended. Thus, a resin varnish for the adhesive layer of Preparation Example 3 (solid content concentration of about 20% by mass) was prepared.

  In addition, the glass transition temperature (Tg) of the resin composition obtained by hardening | curing resin which added 2E4MZ to NC-3000H and YLH-129 was 170 degreeC.

(Preparation Example 4)
(A) Component bisphenol A type epoxy resin (DER-331L, manufactured by Dow Chemical Japan, trade name) 5.0 g, (B) component cresol novolac type phenol resin (KA-1163, Dainippon Ink and Chemicals, Inc.) Made by Kogyo Co., Ltd., trade name) 3.2 g, 50 g of NMP solution of polyamideimide obtained in Synthesis Example 1 as component (C) was blended. Furthermore, after adding 0.025 g of 2-ethyl-4-methylimidazole (2E4MZ, manufactured by Shikoku Kasei Kogyo Co., Ltd., trade name) as a curing accelerator, 46 g of N-methyl-2-pyrrolidone and 15 g of methyl ethyl ketone were blended. Thus, a resin varnish for the adhesive layer of Preparation Example 4 (solid content concentration of about 20% by mass) was prepared.

  In addition, the glass transition temperature (Tg) of the resin composition obtained by hardening | curing resin which added 2E4MZ to DER-331L and KA-1163 was 135 degreeC.

(Comparative Preparation Example 1)
50 g of N-methyl-2-pyrrolidone was added to 50 g of the NMP solution of polyamideimide obtained in Synthesis Example 1 to prepare an adhesive resin varnish of Comparative Preparation Example 1 (solid content concentration of about 15% by mass).

(Comparative Preparation Example 2)
8.8 g of a cresol novolac type epoxy resin (YDCN-500, manufactured by Tohto Kasei Co., Ltd., trade name) was blended with 50 g of the NMP solution of polyamideimide obtained in Synthesis Example 2. Furthermore, after adding 0.088 g of 2-ethyl-4-methylimidazole (2E4MZ, manufactured by Shikoku Kasei Kogyo Co., Ltd.) as a curing accelerator, 101 g of N-methyl-2-pyrrolidone and 34 g of methyl ethyl ketone were blended. Thus, a resin varnish for the adhesive layer of Comparative Preparation Example 2 (solid content concentration of about 15% by mass) was prepared.

[Preparation of prepreg for insulating resin layer (insulating layer)]
(Production Example 1)
First, in a 2 L separable flask equipped with a cooling tube, a thermometer, and a stirrer, 400 g of toluene and 120 g of a polyphenylene ether resin (modified PPO-noryl PKN4752, manufactured by Nippon GE Plastics Co., Ltd., trade name) were placed. The solution was stirred and dissolved while heating the temperature to 90 ° C.

  Next, 80 g of triallyl isocyanurate (TAIC, manufactured by Nippon Kasei Kogyo Co., Ltd., trade name) was added to the flask while stirring, and the mixture was cooled to room temperature after confirming that it was dissolved or uniformly dispersed. Next, after adding 2.0 g of α, α′-bis (t-butylperoxy) diisopropylbenzene (Perbutyl P, trade name, manufactured by NOF Corporation) as a radical polymerization initiator, 70 g of toluene was further blended. A varnish for an insulating resin layer having a solid content concentration of about 30% by mass was obtained.

  The impregnated varnish for insulating resin layer was impregnated into a glass fiber having a thickness of 0.1 mm (E glass, manufactured by Nitto Boseki Co., Ltd.) and then dried by heating at 120 ° C. for 5 minutes. A prepreg for an insulating resin layer of a certain production example 1 was obtained.

(Production Example 2)
First, in a 2 L separable flask equipped with a cooling tube, a thermometer, and a stirrer, 333 g of toluene and 26.5 g of polyphenylene ether resin (Zylon S202A, manufactured by Asahi Kasei Chemicals Corporation) are placed, and the temperature in the flask is set. The solution was stirred and dissolved while heating to 90 ° C. Next, 100 g of 1,2-polybutadiene (B-3000, manufactured by Nippon Soda Co., Ltd., trade name) and 15.9 g of N-phenylmaleimide as a crosslinking aid were added to the flask while stirring and dissolved or uniformly dispersed. After confirming, it was cooled to room temperature. Next, after adding 3.0 g of α, α′-bis (t-butylperoxy) diisopropylbenzene (Perbutyl P, trade name, manufactured by NOF Corporation) as a radical polymerization initiator, 70 g of toluene was further blended. A varnish for an insulating resin layer having a solid content concentration of about 30% by mass was obtained.

  The obtained insulating resin layer varnish was impregnated into a 0.1 mm thick glass fiber (E glass, manufactured by Nitto Boseki Co., Ltd.) and then dried by heating at 120 ° C. for 5 minutes to produce a resin content of 50% by mass. The prepreg for insulating resin layers of Example 2 was obtained.

(Production Example 3)
First, in a 10 L separable flask equipped with a condenser, a thermometer, and a stirrer, 5000 mL of tetrahydrofuran (THF) and 100 g of a polyphenylene ether resin (Noryl PPO646-111, manufactured by Nippon GE Plastics, Inc., trade name) The temperature in the flask was stirred and dissolved while heating to 60 ° C. After returning this to room temperature, 540 mL of n-butyllithium (1.55 mol / L, hexane solution) was added under a nitrogen stream and stirred for 1 hour. Furthermore, after adding 100 g of allyl bromide and stirring for 30 minutes, an appropriate amount of methanol was blended, and the precipitated polymer was isolated to obtain an allylated polyphenylene ether.

  Next, in a 2 L separable flask equipped with a cooling tube, a thermometer, and a stirrer, 400 g of toluene and 100 g of the allylated polyphenylene ether were put and dissolved while stirring while heating the temperature in the flask to 90 ° C. Next, 100 g of triallyl isocyanurate (TAIC, manufactured by Nippon Kasei Kogyo Co., Ltd., trade name) was added to the flask while stirring, and the mixture was cooled to room temperature after confirming that it was dissolved or uniformly dispersed. Then, after adding 2.5 g of α, α′-bis (t-butylperoxy) diisopropylbenzene (Perbutyl P, trade name, manufactured by NOF Corporation) as a radical polymerization initiator, 70 g of toluene was further blended. A varnish for an insulating resin layer having a solid content concentration of about 30% by mass was obtained.

  The obtained insulating resin layer varnish was impregnated into a 0.1 mm thick glass fiber (E glass, manufactured by Nitto Boseki Co., Ltd.) and then dried by heating at 120 ° C. for 5 minutes to produce a resin content of 50% by mass. The prepreg for insulating resin layers of Example 3 was obtained.

(Production of metal foil with adhesive layer)
M of the adhesive copper resin varnish obtained in Preparation Examples 1 to 4 and Comparative Preparation Examples 1 and 2 having a thickness of 12 μm (F0-WS-12, low profile copper foil, manufactured by Furukawa Circuit Foil Co., Ltd.) Each of the surfaces (surface roughness (Rz) = 0.8 μm) was naturally cast and then dried at 150 ° C. for 5 minutes to prepare a conductor foil with an adhesive layer. The thickness of the adhesive layer before curing after drying was 3 μm.

[Examples 1 to 4, Comparative Examples 1 and 2]
(Production of double-sided copper-clad laminate)
Either one of the conductor foils with the adhesive layer is adhered to both main surfaces of the base material formed by stacking the four prepregs for insulating resin layer in any of Production Examples 1 to 3 so that the respective adhesive layers are in contact with each other. To obtain a laminate. Thereafter, the laminate was molded by heating and pressing in the laminating direction under press conditions of 200 ° C., 3.0 MPa, 70 minutes, and double-sided copper-clad laminates (thickness: 0.55 mm). The combinations of the resin varnish for adhesive layer and the prepreg for insulating resin layer in each Example or Comparative Example were as shown in Table 1.

  Also, an electrolytic copper foil A (F0-WS-12, Furukawa Electric Co., Ltd.) having a thickness of 18 μm without an adhesive layer formed on both main surfaces of the base material formed by stacking the four prepregs for insulating resin layer of Production Example 1 Manufactured, trade name, Rz = 0.8 μm), or 18 μm thick electrolytic copper foil B (GTS-12, general copper foil, manufactured by Furukawa Electric Co., Ltd., with no adhesive layer, Rz = 8 μm on the M surface, The product name) was applied so that the M-plane was in contact with the main surface of the substrate to obtain a laminate. Thereafter, the laminate was molded by heating and pressing in the laminating direction under press conditions of 200 ° C. and 3.0 MPa for 70 minutes to produce a double-sided copper clad laminate (thickness: 0.55 mm) of Comparative Examples 3 and 4. did. Of these, the one using the electrolytic copper foil A was used as Comparative Example 3, and the one using the electrolytic copper foil B was used as the double-sided copper clad laminate (thickness: 0.55 mm) of Comparative Example 4.

(Production of multilayer substrate)
First, similarly to the above, double-sided copper-clad laminates of Examples 1 to 4 and Comparative Examples 1 to 4 were formed, and these copper foil portions were completely removed by etching. After that, the same prepreg as the insulating resin layer prepreg used in the production of the copper clad laminate was placed on each side of the double-sided copper clad laminate after removing the copper foil, and no adhesive layer was provided on the outside. After depositing an electrolytic copper foil having a thickness of 12 μm (GTS-12, general copper foil, manufactured by Furukawa Electric Co., Ltd., Rz = 8 μm of M surface, product name) so that the M surface is in contact, 200 ° C., Molding was performed by heating and pressing in the laminating direction under a pressing condition of 3.0 MPa for 70 minutes to produce a multilayer substrate.

[Measurement of peel strength of copper foil in copper-clad laminate]
The double-sided copper-clad laminate obtained in Examples 1 to 4 and Comparative Examples 1 to 4 is subjected to a process of removing unnecessary copper foil portions by etching so that the copper foil has a circuit shape with a line width of 5 mm. A laminate sample having a planar shape of 2.5 cm × 10 cm was produced. The sample thus prepared was held in an apparatus for normal and pressure cooker test (PCT) (conditions: 121 ° C., 2.2 atm, 100% RH) for 5 hours, and then peeled off with copper foil (unit: kN / m) was measured under the following conditions. The obtained results are shown in Table 1.
Test method: 90 ° C direction tensile test Tensile speed: 50 mm / min Measuring device: Shimadzu Autograph AG-100C

  In addition, about this copper foil peeling strength, what was shown by "-" in a table | surface was that copper foil had already peeled after hold | maintaining in PCT, Therefore The copper foil peeling strength was not able to be measured Means.

[Evaluation of solder heat resistance of copper-clad laminates and multilayer boards]
After cutting the double-sided copper-clad laminate and the multilayer substrate obtained in Examples 1 to 4 and Comparative Examples 1 to 4 into 50 mm squares, the double-sided copper-clad laminate is obtained by etching the copper foil on one side into a predetermined shape. In addition, after removing the copper foil of the outer layer completely by etching, the multilayer substrate is subjected to a normal time and an apparatus for pressure cooker test (PCT) (conditions: 121 ° C., 2.2 atm) for a predetermined time (1 to 5 hours). Retained. Thereafter, these were immersed in a molten solder at 260 ° C. for 20 seconds, and the appearance of each of the double-sided copper-clad laminate and the multilayer board after the treatment was visually examined. The obtained results are shown in Table 1. In addition, the number in a table | surface means the number of sheets which did not swell and generation | occurrence | production of a mesling between an insulating layer and copper foil (electroconductive layer) among three copper clad laminated boards after a solder immersion. It means that it is excellent in solder heat resistance, so that this number is large.

[Evaluation of transmission loss of copper-clad laminate]
The transmission loss (unit: dB / m) of the double-sided copper-clad laminates of Examples 1 to 4 and Comparative Examples 1 to 4 was measured by a triplate line resonator method using a vector network analyzer. The measurement conditions were: line width: 0.6 mm, insulating layer distance between upper and lower ground conductors: 1.04 mm, line length: 200 mm, characteristic impedance: about 50Ω, frequency: 3 GHz, measurement temperature: 25 ° C. The obtained results are shown in Table 1.

DESCRIPTION OF SYMBOLS 1 ... Conductor-clad laminated board, 2 ... Insulating layer, 4 ... Adhesive layer, 6 ... Conductor layer, 10 ... Wiring board, 12 ... Insulating layer, 14 ... Adhesive layer, 16 ... Circuit pattern, 20 ... Multilayer wiring board, 22 ... Insulating layer, 24 ... adhesive layer, 26 ... inner layer circuit pattern, 28 ... interlayer insulating layer, 30 ... outer layer circuit pattern, 32 ... via hole, 34 ... through hole, 40 ... core substrate.

Claims (16)

An insulating layer, a conductor layer disposed opposite to the insulating layer, and an adhesive layer sandwiched between the insulating layer and the conductor layer,
The adhesive layer is
(A) component; a polyfunctional epoxy resin;
(B) component; polyfunctional phenol resin;
(C) Component: A conductor-clad laminate comprising a cured product of a resin composition containing a polyamide resin.   The conductor-clad laminate according to claim 1, wherein the component (A) and the component (B) have a glass transition temperature of 150 ° C. or higher after curing of the mixture.   The component (A) is a phenol novolak type epoxy resin, a cresol novolak type epoxy resin, a brominated phenol novolak type epoxy resin, a bisphenol A novolak type epoxy resin, a biphenyl type epoxy resin, a naphthalene skeleton-containing epoxy resin, an aralkylene skeleton-containing epoxy resin. , Biphenyl-aralkylene skeleton-containing epoxy resin, phenol salicylaldehyde novolak type epoxy resin, lower alkyl group-substituted phenol salicylaldehyde novolak type epoxy resin, dicyclopentadiene skeleton containing epoxy resin, polyfunctional glycidylamine type epoxy resin and polyfunctional alicyclic type The conductor-clad laminate according to claim 1 or 2, comprising at least one polyfunctional epoxy resin selected from the group consisting of epoxy resins.   The component (B) is composed of an aralkyl type phenol resin, a dicyclopentadiene type phenol resin, a salicylaldehyde type phenol resin, a copolymer type resin of a benzaldehyde type phenol resin and an aralkyl type phenol resin, and a novolac type phenol resin. The conductor-clad laminate according to any one of claims 1 to 3, comprising at least one polyfunctional phenol resin selected from the above.   The conductor-clad laminate according to any one of claims 1 to 4, wherein the component (C) includes a structural unit composed of a saturated hydrocarbon.   The blending ratio of the component (C) is 10 to 400 parts by mass with respect to a total of 100 parts by mass of the component (A) and the component (B), according to any one of claims 1 to 5. Conductor-clad laminate.   The conductor-clad laminate according to any one of claims 1 to 6, wherein the adhesive layer has a thickness of 0.1 to 10 µm.   The conductor-clad laminate according to any one of claims 1 to 7, wherein a ten-point average roughness (Rz) of the surface on the adhesive layer side in the conductor layer is 4 µm or less. The insulating layer is composed of an insulating resin and a base material disposed in the insulating resin,
The conductor according to any one of claims 1 to 8, comprising a woven or nonwoven fabric of fibers made of at least one material selected from the group consisting of glass, paper, and an organic polymer compound as the base material. Tension laminate.   The conductor-clad laminate according to claim 9, wherein the insulating layer contains a resin having an ethylenically unsaturated bond as the insulating resin.   The insulating resin contains at least one resin selected from the group consisting of polybutadiene, polytriallyl cyanurate, polytriallyl isocyanurate, unsaturated group-containing polyphenylene ether and maleimide compound. Conductor-clad laminate.   The conductor-clad laminate according to any one of claims 9 to 11, wherein the insulating resin contains at least one resin selected from the group consisting of polyphenylene ether and thermoplastic elastomer.   The conductor-clad laminate according to any one of claims 1 to 12, wherein the insulating layer has a relative dielectric constant of 4.0 or less at 1 GHz.   Laminating a film containing the insulating resin and a base material disposed in the insulating resin on the uncured layer of the conductive foil with an adhesive layer, comprising a layer before the adhesive layer is cured on the conductor foil The conductor-clad laminate according to any one of claims 1 to 13, which is obtained by heating and pressurizing the laminate after obtaining the laminate.   The printed wiring board obtained by processing the said conductor foil in the conductor clad laminated board as described in any one of Claims 1-14 so that it may have a predetermined circuit pattern. A multilayer wiring board comprising: a core substrate having at least one printed wiring board; and an outer wiring board disposed on at least one side of the core substrate and having at least one printed wiring board,
The multilayer wiring board according to claim 15, wherein at least one of the printed wiring boards in the core substrate is a printed wiring board according to claim 15.

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