TW201611670A - Printed circuit board resin laminate for forming fine via hole, and multilayer printed circuit board having fine via hole in resin insulating layer and method for manufacturing same - Google Patents

Abstract

Provided is a method for processing or manufacturing a printed circuit board in which it is possible to form a via hole in which the top diameter is reduced and the difference between the top diameter and the bottom diameter is smaller. Also provided is a resin laminate used in this method. A printed wiring board resin laminate including a resin insulating layer for forming a fine via hole and a release film for laser attenuation laminated on the resin insulating layer, wherein the thickness of the release film for laser attenuation is set to over 50 [mu]m and no more than 180 [mu]m, making it possible to form a via hole having a top diameter of 30 [mu]m or less and a difference between the top diameter and the bottom diameter of 10 [mu]m or less.

Description

Resin laminate for printed circuit board for forming fine via hole and multilayer printed circuit board provided with fine via hole in resin insulating layer and manufacturing method thereof

The present invention relates to a resin laminate for a printed wiring board for forming fine via holes, and a multilayer printed wiring board having fine via holes in a resin insulating layer and a method for producing the same.

In recent years, in order to increase the mounting density of electronic components and to improve the miniaturization of the conductor wiring, the multilayer printed circuit board has been developed to reduce the size of the electronic device. As a method of forming a high-density fine wiring on an insulating layer, there is known a method in which an additive method is used to form a conductor layer only by electroless plating, and a thin copper is formed entirely by electroless plating. After the layer, a conductor layer is formed by electrolytic plating, and then the thin copper layer is subjected to a rapid etching half-addition method or the like.

A through hole and a blind via hole which are necessary for interlayer connection of a printed circuit board are formed by laser processing or drilling. As a method of forming a blind via hole by laser processing, a method using a UV-YAG laser and a method using a carbon dioxide laser are known. Although the UV-YAG laser has good workability for small diameter holes, it is not satisfactory from the viewpoint of cost and processing speed. The carbon dioxide laser is excellent in cost and processing speed, but has a long wavelength and a large spot diameter. Therefore, the processing of the small diameter hole is worse than that of the UV-YAG laser having a short wavelength and a small spot diameter. When forming blind vias with small diameters by carbon dioxide laser, it must be processed with low processing energy, so the diameter of the bottom is smaller than that of the top, which becomes a strong push-pull shape, so that the conduction reliability of the blind vias is made. The reason for the decrease.

Patent Documents 1 to 3 describe a method of manufacturing a multilayer printed wiring board using an adhesive film, and Patent Document 1 discloses that an adhesive film composed of a supporting base film having a release layer and a thermosetting resin composition is used in a core substrate. The adhesive film is laminated and thermally cured in a state in which a supporting base film is attached, and the method of attaching the supporting base film or peeling and then opening the hole by a laser or a drill is maintained. Further, Patent Document 2 discloses a method in which an insulating layer is laminated on one surface of a metal foil, and an organic film which can be peeled off is laminated on the surface of the insulating layer, and laser processing is performed from the surface side of the organic film. Further, Patent Document 3 discloses that when a blind via hole is formed using a carbon dioxide laser in an insulating layer containing a large amount of inorganic filler, the difference between the diameter of the top portion and the diameter of the bottom of the via hole is formed so that no large unevenness is formed on the surface of the insulating layer around the via hole. A small well-formed blind via is formed, and a carbon dioxide laser is used for the insulating layer of the laminated plastic film. Patent Documents 1 and 2 relate to the formation of a mesopores having a top diameter of 100 μm or more, and Patent Document 3 discloses that the top diameter is 100 μm or less, preferably 90 μm or less, and more preferably 80 μm or less. Therefore, these documents do not mention the formation of fine interbed pores having a top diameter of 30 μm or less. [Prior Technical Literature] [Patent Literature]

[Patent Document 1] JP-A-2001-196743 [Patent Document 2] Japanese Patent No. 3899544 (Patent Document 3) International Publication No. 2009/066759

[The subject to be solved by the invention]

When a via hole is formed in a resin insulating layer used for a printed circuit board, the output diameter of the carbon dioxide laser is lowered in order to reduce the diameter of the via hole, and the diameter of the top diameter becomes a strong push-out shape. The problem of the difference between the top diameter and the bottom diameter increases. Therefore, it is still desired to have a method of processing or manufacturing a printed circuit board capable of forming a via hole having a small diameter at the top and a small difference between the top diameter and the bottom diameter, and a resin laminate used in the method. [Method of solving the problem]

The inventors of the present invention have made an effort to study a method of forming a via hole having a small top diameter and a small difference between a top diameter and a bottom diameter by a laser (preferably a carbon dioxide laser), and found that when a layer laminated on a resin insulating layer is provided When the thickness of the release film for radiation attenuation is more than 50 μm to 180 μm or less, fine mesopores having a top diameter of 30 μm or less and a difference between the top diameter and the bottom diameter of 10 μm or less can be formed, and the present invention has been completed.

Therefore, the present invention relates to the following: [1] A resin laminate comprising a resin insulating layer for forming fine via holes and a printed circuit board for releasing a release film for laser lightening of the resin insulating layer. With the resin laminate, the thickness of the release film exceeds 50 μm and is 180 μm or less. [2] The resin laminate according to [1], wherein the release film for laser attenuation is formed of polyester. [3] The resin laminate according to [2], wherein the polyester is selected from the group consisting of polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polynaphthalene. One or more of the group consisting of butylene glycol dicarboxylate (PBN), polybutylene terephthalate (PBT), and polytrimethylene terephthalate (PTT). [4] The laminate according to any one of [1] to [3] wherein the diameter of the top of the via hole formed in the resin insulating layer is 30 μm or less, and the difference between the top diameter and the bottom diameter is 10 μm or less. . [5] The resin laminate according to any one of [1] to [4] wherein the resin insulating layer has a thickness of 3 to 50 μm. [6] The resin laminate according to any one of [1] to [5] wherein the resin insulating layer is formed of a thermosetting resin composition. [7] The resin laminate according to [6], wherein the thermosetting resin composition contains an epoxy resin, a cyanate compound, and an inorganic filler. [8] The resin laminate according to [6] or [7], wherein the thermosetting resin composition is semi-hardened. [9] The resin laminate according to any one of [1] to [8] wherein the resin insulating layer has a plating peel strength of 0.4 kN/m or more. [10] A method of manufacturing a multilayer printed circuit board, comprising the steps of: laminating a resin according to any one of [1] to [9], in a circuit substrate having a substrate and a conductive circuit formed on the substrate The body is laminated such that the conductive circuit of the circuit substrate faces the surface of the resin insulating layer of the resin laminate, and is formed by laser to form a side of the release film for laser attenuation from the resin laminate. The via hole of the resin insulating layer peels the release film from the resin insulating layer. [11] The method for producing a multilayer printed circuit board according to [10], wherein the resin laminate is a resin laminate of [8], and the circuit substrate is laminated with the resin laminate, Before the formation of the via hole, the step of fully hardening the resin insulating layer in a semi-hardened state is further included. [12] The method of manufacturing a multilayer printed circuit board according to [10] or [11], wherein the laser is a carbon dioxide laser. [13] The method of manufacturing a multilayer printed circuit board according to [12], wherein the energy of the laser is 0.3 mJ to 5 mJ. [14] The method of manufacturing a multilayer printed circuit board according to any one of [10] to [13] wherein the diameter of the top of the via hole formed in the resin insulating layer is 30 μm or less, and the difference between the top diameter and the bottom diameter It is 10 μm or less. [15] The method for producing a multilayer printed circuit board according to any one of [10] to [14] wherein, after the release film is peeled off, the method further comprises the steps of: roughening the surface of the resin insulating layer The conductor layer is formed by plating on the roughened surface, and the conductor layer is patterned to form an electric circuit. [16] A multilayer printed circuit board obtained by the method of manufacturing a multilayer printed circuit board according to any one of [10] to [15]. [17] A multilayer printed circuit board comprising: a circuit substrate having a substrate and a conductive circuit formed on the substrate; and a resin stack laminated to the circuit substrate according to any one of [1] to [9] The resin insulating layer of the layered body has a via hole formed by laser, and the top diameter of the via hole is 30 μm or less, and the difference between the top diameter and the bottom diameter is 10 μm or less. [Effects of the Invention]

When the appropriate output energy is selected, the resin laminate of the present invention can be formed by a laser from the side of the release film in the state of the release film for laser attenuation. The release film for attenuation is attenuated or cut off by a laser of low energy intensity. Thereby, the resin insulating layer can form a via hole having a small top diameter and a small difference between the top diameter and the bottom diameter. Therefore, by laminating the resin laminate of the present invention on a circuit board and forming a via hole, a multilayer printed wiring board including a via hole having a small diameter and high electrical conductivity reliability can be formed.

One aspect of the present invention relates to a resin laminate for a printed circuit board including a resin insulating layer for forming fine via holes and a release film for laser light reduction laminated on the resin insulating layer. The thickness of the release film is more than 50 μm and is not more than 180 μm.

The resin constituting the resin insulating layer in the resin laminate of the present invention can be a resin which can be used for the production of a printed circuit board and can form a fine via hole by using a laser (preferably a carbon dioxide laser). The insulating resin may be any resin. The resin composition generally does not have a significant effect on the size of the pores formed when using a laser.

In the present invention, the fine via hole formed in the resin insulating layer means a via hole having a top diameter of the via hole of 30 μm or less and a difference between the top diameter and the bottom diameter of 10 μm or less. From the viewpoint of improving the electrical conductivity reliability, the smaller the difference between the top diameter and the bottom diameter, the better, more preferably 8 μm or less, and still more preferably 5 μm or less. From the viewpoint of miniaturization of the conductor wiring, the smaller the top diameter, the better, for example, 30 μm or less, more preferably 27 μm or less, and still more preferably 25 μm or less. On the other hand, from the viewpoint of improving the electrical conductivity reliability, the top diameter is usually preferably 15 μm or more.

The thickness of the resin insulating layer may be selected to be any thickness within a range in which the diameter of the top of the via hole and the difference between the top diameter and the bottom diameter of the via hole can be achieved. The upper limit of the thickness of the resin insulating layer is preferably 50 μm or less, more preferably 30 μm or less, still more preferably 20 μm or less, from the viewpoint of forming a via hole having a difference between the top diameter and the bottom diameter of 10 μm or less. On the other hand, the lower limit of the thickness of the insulating layer, from the viewpoint of the insulation reliability of the insulating layer, is preferably 3 μm or more, more preferably 5 μm or more, and still more preferably 10 μm or more.

The size of the via hole necessary for connection between the layers of the printed circuit board is desirably finer because of the miniaturization and high density of the wiring. A printed circuit board using a fine via hole requires the wiring itself formed on the wiring board to be fine. As a method of forming a high-density fine wiring, there are an additive method and a semi-additive method which are known to form fine wiring by electroless plating or electrolytic plating. However, when the wiring is made fine, the adhesion area between the insulating layer and the wiring is reduced, and there is a problem that the wiring is easily peeled off. Therefore, from the viewpoint of miniaturization and high density of wiring, it is desirable that the resin insulating layer have a higher plating peeling strength when forming a finer via hole.

In the production of a printed circuit board, the plating peeling strength of the resin insulating layer is preferably 0.4 kN/m or more, more preferably 0.5 kN/m or more, from the viewpoint of preventing peeling of the plating formed in the resin insulating layer. The peel strength of the plating varies depending on the surface roughness of the resin insulating layer. The range of the plating peeling described above may be any range of the plating peeling strength before the roughening treatment or after the roughening treatment, but preferably refers to the range of the plating peel strength after the roughening treatment.

[Release film] Conventionally, a release film is generally used for preventing adhesion to a pressurizing means when a resin insulating layer is laminated on a circuit board having a conductive circuit and heated and pressurized. In this case, after the resin laminate is adhered to the circuit board, the release film is peeled off, and the surface of the resin insulating layer is roughened, the conductor layer is formed by plating on the roughened surface, and the conductor layer is patterned. Form the circuit. On the other hand, in the aspect of the invention, the release film has a laser attenuation application in addition to the use for preventing adhesion to a pressurizing means.

In the present invention, the laser attenuation means that the low-intensity laser which is the cause of the hole profile which becomes the resin insulating layer in the distribution of the laser intensity of the laser is blocked or attenuated. The intensity distribution of the laser is usually a Gaussian distribution (Fig. 1), but when the mask (small hole) is thinned by the beam diameter, the light interferes and interference fringes appear. Even a laser having a low-intensity distribution corresponding to a portion containing such interference fringes partially cuts off the resin insulating layer to cause the push-out (Fig. 2A). Therefore, the release film for laser attenuation of the present invention is not intended to be limited to the theory, for example, by attenuating or blocking the laser of a low intensity distribution including a portion of the interference fringe in the distribution of the laser intensity. The pushing of the formed holes is minimized. The intensity of the laser that is blocked or attenuated varies depending on the thickness of the release film for laser attenuation. If it is generally known in the art, the laser attenuation suitable for the formation of fine via holes can be appropriately selected. The thickness of the release film.

The release film for laser attenuation of the present invention is not intended to be limited to the theory, but can be reduced by preventing the recess of the resin insulating layer due to the laser spread on the low-intensity side of the laser intensity distribution. Pushing out the hole formed by the resin insulating layer. Therefore, the release film for laser attenuation of the present invention is required to prevent a sufficient thickness of the resin insulating layer from being recessed due to low-intensity laser light in the laser intensity distribution, and this thickness is considered to achieve an ideal laser interception or attenuation. The viewpoint is preferably more than 50 μm. More preferably, it is more than 60 μm, and more preferably more than 70 μm. On the other hand, if the thickness is increased, the laser output for forming the through hole must be increased. In this case, the diameter of the top of the hole is increased, which is not preferable. From this point of view, the upper limit of the thickness of the release film is preferably 180 μm or less. More preferably, it is 150 μm or less, and more preferably 100 μm or less.

The release film for laser attenuation may be any film as long as it is attenuated by laser energy and can be peeled off after thermal curing of the resin insulating layer, for example, polyester, polycarbonate (hereinafter referred to as "PC"), polymethyl methacrylate. An acrylic resin such as (PMMA), a cyclic polyolefin, triethylenesulfonyl cellulose (TAC), polyether sulfide (PES), polyether ketone, or polyimine. Among them, polyester is preferred, and polyethylene naphthalate (hereinafter sometimes referred to as "PEN"), polyethylene terephthalate (PET), and polybutylene naphthalate (preferably referred to as "PEN"). PBN), polybutylene terephthalate (PBT), and polytrimethylene terephthalate (PTT). Further, as the release film for laser attenuation, a laser absorbing component such as soot may be used. In addition, in the release film, a release layer may be provided on the surface to be formed of the thermosetting resin composition layer in order to peel off the release film after heat-hardening the thermosetting resin composition layer. The release agent to be used as the mold release layer is not particularly limited as long as it can be peeled off after the thermosetting resin composition layer is thermally cured, and is, for example, an anthrone-based release agent or an alkyd resin. It is a release agent and the like.

The resin laminate of the present invention can be produced by a method known to those skilled in the art, for example, a resin varnish in which an organic solvent is dissolved in a thermosetting resin composition, and the resin varnish is coated with a die coater or the like. The cloth is produced on the support film by drying the organic solvent by heating or hot air blowing to form a resin composition layer. Since the resin laminated system is laminated on the circuit board and then cured, it is preferably semi-hardened.

[Resin Insulation Layer] The resin used in the resin insulating layer of the present invention is not particularly limited as long as it is a resin that can be used for the insulating layer of the printed circuit board, and the viewpoint of heat resistance, insulation, and plating adhesion is considered. A thermosetting resin is preferred. Specific examples of the thermosetting resin include an epoxy resin, a cyanate resin, a bismaleimide resin, a quinone imine resin, a phenol resin, a double bond addition polyphenylene ether resin, an unsaturated polyester resin, and the like. . These may be used alone or in combination of two or more kinds in any combination. Among them, from the viewpoint of providing a resin insulating layer having excellent peel strength, a mixture of an epoxy resin and a cyanate resin is preferable, but a bismaleimide resin is preferably added. In the resin composition used for the resin insulating layer of the present invention, for example, in order to carry out curing of the epoxy resin, it is preferred to use a curing agent. Further, in the case of using a curing agent, a curing accelerator may be used in combination in order to appropriately adjust the curing rate. Further, from the viewpoint of low thermal expansion, it is preferred that the resin composition used in the insulating layer of the present invention contains an inorganic filler in a range that does not impair the desired properties.

[Epoxy resin] The epoxy resin used as the thermosetting resin as the resin insulating layer may be any one of two or more epoxy groups in one molecule, and the type thereof is not limited, and any conventionally known one can be used. Epoxy resin. Examples of the epoxy resin include a biphenyl aralkyl type epoxy resin, a naphthalene 4-functional epoxy resin, a xylene type epoxy resin, a naphthol aralkyl type epoxy resin, and a bisphenol A type epoxy resin. Bisphenol F type epoxy resin, resin, bisphenol A novolak type epoxy resin, trifunctional phenol type epoxy resin, tetrafunctional phenol type epoxy resin, naphthalene type epoxy resin, biphenyl type epoxy resin, aromatic Alkyl novolac type epoxy resin, alicyclic epoxy resin, polyol type epoxy resin, glycidylamine, glycidyl ester, compound obtained by epoxidizing a double bond such as butadiene, and a hydroxyl group-containing compound A compound obtained by reacting an anthrone resin with epichlorohydrin. Among these, in particular, from the viewpoint of adhesion of copper plating and flame retardancy, a biphenyl aralkyl type epoxy resin, a naphthalene 4-functional epoxy resin, a xylene type epoxy resin, a naphthol aralkyl type Epoxy resin is especially preferred. These epoxy resins may be used alone or in combination of two or more.

The biphenyl aralkyl type epoxy resin is, for example, a structure represented by the formula (1), the naphthalene 4 functional type epoxy resin is, for example, a structure represented by the formula (2), and the xylene type epoxy resin is, for example, the formula (3). The structure represented by the formula, the naphthol aralkyl type epoxy resin has a structure represented by the formula (4), for example.

【化1】 (wherein n1 represents an integer of 1 or more.)

[Chemical 2]

[化3] (wherein n2 represents an integer of 1 or more.)

【化4】 (n3 represents the average enthalpy, which is a number from 1 to 6, and X represents a glycidyl group or a hydrocarbon group having 1 to 8 carbon atoms, and the ratio of the hydrocarbon group to the epoxy group is 0.05 to 2.0.)

The weight average molecular weight (Mw) of the epoxy resin is not limited, but the viewpoint of exhibiting the flexibility of the cured resin is usually 250 or more, of which 300 or more is preferable, and the coating property of the uncured resin and the heat resistance of the hardened resin are considered. The viewpoint of improving the sex is usually 5,000 or less, and preferably 3,000 or less.

In the resin composition used for the resin insulating layer of the present invention, the content of the epoxy compound is not particularly limited, and from the viewpoint of heat resistance and hardenability, it accounts for 20 to 80% by mass of the resin solid content in the resin composition. Ideally, the range of 30 to 70% by mass is particularly desirable.

[Malayimine compound] A maleic imine compound having a maleidino group, for example, bis(4-maleimidophenyl)methane, 2,2-double {4-(4) -Malyleneimine phenoxy)-phenyl}propane, bis(3,5-dimethyl-4-maleimidophenyl)methane, bis(3-ethyl-5-methyl- 4-maleimide phenyl)methane, bis(3,5-diethyl-4-maleimidophenyl)methane, polyphenylmethane maleimide as other components, used in the composition A resin composition of a resin insulating layer which can improve the moisture absorption heat resistance of the insulating layer. In addition, one type of the prepolymer of the maleic imine compound or the prepolymer of the maleimide compound and the prepolymer of the amine compound may be used, and one type or two or more types may be used as appropriate.

[Curing Agent] The curing agent is not particularly limited as long as it is generally used as a curing agent for the thermosetting resin. Examples thereof include a phenol compound, a polyphenol compound, a cyanate compound, an active ester compound, dicyandiamide, a carboxylic acid guanamine, an amine compound, various acid anhydrides, and a Lewis acid complex. These may be used alone or in combination of two or more kinds in any group and ratio. When a curing agent is used, the ratio of use thereof is not limited. For example, it is usually used in an amount of 1 part by mass or more, more than 5 parts by mass, and usually 100 parts by mass or less, based on 100 parts by mass of the resin solid content of the thermosetting resin. 70 parts by mass or less is preferred. Further, the ratio of use of the thermosetting resin to the curing agent varies depending on the type of the thermosetting resin and the curing agent, for example, a reactive group of the thermosetting resin (represented by RF1) and a curing agent reactive therewith The ratio (RF2/RF1) of the reactivity group (represented by RF2) is usually 0.3 or more, and 0.7 or more, and usually 3 or less, preferably 2.5 or less is preferably used.

The cyanate compound which is used as a curing agent is excellent in chemical resistance, adhesiveness, and the like, and can form a uniform roughened surface by using such excellent chemical resistance. Therefore, it is suitably used as a resin composition in the present invention. The ingredients. As the cyanate ester compound, a naphthol aralkyl type cyanate compound represented by the formula (5), a novolac type cyanate represented by the formula (6), and a biphenyl aryl group represented by the formula (7) can be used. Alkyl type cyanate, 1,3-dicyanooxybenzene, 1,4-dicyanooxybenzene, 1,3,5-tricyanooxybenzene, bis(3,5-dimethyl 4- Cyanooxyphenyl)methane, 1,3-dicyanooxynaphthalene, 1,4-dicyanooxynaphthalene, 1,6-dicyanooxynaphthalene, 1,8-dicyanooxynaphthalene, 2, 6-Dicyanooxynaphthalene, 2,7-dicyanooxynaphthalene, 1,3,6-tricyanooxynaphthalene, 4,4'-dicyanoxybiphenyl, bis(4-cyanooxybenzene) Methane, bis(4-cyanooxyphenyl)propane, bis(4-cyanooxyphenyl)ether, bis(4-cyanooxyphenyl) sulfide, bis(4-cyanooxyphenyl)碸, 2,2'-bis(4-cyanooxyphenyl)propane, bis(3,5-dimethyl, 4-cyanooxyphenyl)methane, and the like.

Among them, the naphthol aralkyl type cyanate compound represented by the formula (5), the novolak type cyanate represented by the formula (6), and the biphenyl aralkyl type cyanate represented by the formula (7) are flame retarded. It is particularly preferable because it has excellent properties, high hardenability, and low thermal expansion coefficient of the cured product. 【化5】 (wherein R1 represents a hydrogen atom or a methyl group, and n4 represents an integer of 1 or more.)

【化6】 (wherein R2 represents a hydrogen atom or a methyl group, and n5 represents an integer of 1 or more.)

【化7】 (wherein R3 represents a hydrogen atom or a methyl group, and n6 represents an integer of 1 or more.)

The active ester compound used as a curing agent has excellent characteristics such as low dielectric constant, low dielectric tangent, low water absorption, low thermal expansion coefficient, high glass transition temperature, and excellent electrical properties and high glass transition temperature, so it is suitable as The component of the resin composition of the present invention is used. A generally known product can be used, but EPICLON HPC-8000 (DIC) and EPICLON HPC-8000-65T (DIC) are preferred examples.

[Inorganic Filler] The inorganic filler is not particularly limited as long as it is generally used by the user in the technical field. Further, one type or a plurality of inorganic fillers may be used. Inorganic fillers such as magnesium hydroxide, magnesium oxide, natural cerium oxide, molten cerium oxide, amorphous cerium oxide, hollow cerium oxide, cerium oxide, boehmite, molybdenum oxide, zinc molybdate, etc. Molybdenum compound, alumina, talc, calcined talc, mica, glass short fiber, spherical glass (glass micropowder such as E glass, T glass, D glass), and the like. In particular, from the viewpoint of providing a resin structural body having a resin insulating layer having a desired plating releasability, an acid-soluble inorganic filler is preferred. By containing an acid-soluble inorganic filler, a roughened surface having a low roughness can be formed on the surface of the insulating layer, and a resin insulating layer excellent in plating adhesion when metal plating is formed on the roughened surface can be obtained. . This effect is not limited to theory, but it is presumed that the acid-soluble inorganic filler is insoluble in the roughening step by the alkaline oxidizing agent in the desmear treatment step, and is in the middle of using the acidic reducing agent. And the step of dissolving, and the use of the cyanate ester compound can provide a resin structure having high chemical resistance, whereby the effect of the acid-soluble inorganic filler does not fall off even in the roughening step using the alkaline oxidizing agent Earned.

The inorganic filler which is soluble in acid used in the present invention may, for example, be magnesium hydroxide or magnesium oxide. These materials have the effect of dissolving in the desizing treatment on the surface of the insulating layer to form a uniform roughened surface and improving the peeling strength of the plating. Specifically, as the magnesium hydroxide, Ecomag Z-10, Ecomag PZ-1 manufactured by Tateho Chemical Industry Co., Ltd., Magseeds N, Magseeds S, Magseeds EP, Magseeds EP2 manufactured by Shendao Chemical Industry Co., Ltd. -A, MGZ-1, MGZ-3, MGZ-6R, manufactured by 堺Chemical Industries Co., Ltd., Kisuma 5, Kisuma 5A, Kisuma 5P, etc., manufactured by Kyowa Chemical Industry Co., Ltd. Examples of the magnesium oxide include FNM-G manufactured by Tateho Chemical Industry Co., Ltd., SMO, SMO-0.1, SMO-S-0.5 manufactured by Nippon Chemical Industry Co., Ltd., and the like.

The average particle diameter of the above-mentioned acid-soluble inorganic filler is preferably from 0.1 to 2.0 μm from the viewpoint of obtaining a uniform surface roughness after the desmear treatment. Here, the average particle diameter refers to the median diameter. When the particle size distribution of the measured powder is divided into two parts, the number of the larger side or the mass of the side and the mass of the side are 50 of the total powder. The particle size at % is generally measured by a wet laser diffraction/scattering method.

In the resin composition used for the resin insulating layer of the present invention, the content of the acid-soluble inorganic filler is from 5 to 150 parts by mass based on 100 parts by mass of the resin solid content in the resin composition, from the surface of the insulating layer. The viewpoint of roughness is ideal.

Moreover, when the acid-soluble inorganic filler is surface-treated, it is preferable from the viewpoints of moisture absorption heat resistance and chemical resistance. Specifically, it is preferred to carry out the decane coupling treatment, the KBM-403 treatment, and the KBM-3063 treatment for the decane coupling agent.

The decane coupling agent is not particularly limited as long as it is a decane coupling agent which is generally used for the surface treatment of an inorganic material. Specific examples thereof include γ-aminopropyltriethoxydecane, N-β-(aminoethyl)-γ-aminopropyltrimethoxydecane, and the like, and an oxane-glycidyloxy group. Ethylene decane such as propyltrimethoxydecane, vinyl decane such as γ-methyl propylene oxypropyltrimethoxy decane, or N-β-(N-vinylbenzylaminoethyl)-γ-amine A cationic decane type or a phenyl decane type, such as a propyl trimethoxy decane hydrochloride, may be used alone or in combination of two or more kinds as appropriate. Further, the wetting dispersant is not particularly limited as long as it is a dispersion stabilizer used for coating applications. For example, a wet dispersant such as Disperbyk-110, 111, 180, 161, BYK-W996, W9010, W903 manufactured by BYK Japan Co., Ltd.

[Curing accelerator] The hardening accelerator is an optional component, and may be added to the resin composition in order to appropriately adjust the curing rate. These are not particularly limited as long as they are known as a curing accelerator for a cyanate compound or an epoxy resin. Specific examples thereof include organic metal salts such as copper, zinc, cobalt, and nickel, imidazoles and derivatives thereof, dimethylaminopyridine, and tertiary amines. These hardening accelerators may be used singly or in combination of two or more kinds in any combination.

[Other Components] The curable resin composition may contain other components as long as it does not deviate from the gist of the present invention. Other polymer compounds such as other thermosetting resins, thermoplastic resins, oligomers thereof, and elastomers, other flame retardant compounds, additives, and the like can be used in combination as the other components. As long as it is a general user, there is no particular limitation. For example, the flame retardant compound may be a nitrogen compound such as a phosphate ester, a melamine phosphate, a phosphorus-containing epoxy resin, a melamine or a benzoguanamine, or the like. a compound of a ring, an anthrone-based compound, or the like. It can be used as an additive for UV absorbers, antioxidants, photopolymerization initiators, fluorescent brighteners, photosensitizers, dyes, pigments, tackifiers, lubricants, defoamers, dispersants, and coatings. Flat agents, brighteners, and the like are used in an appropriate combination.

Other polymer compounds such as other thermosetting resins, thermoplastic resins, oligomers thereof, and elastomers, other flame retardant compounds, additives, and the like may be used in combination. Further, examples thereof include diced or pulverized fibers such as glass fibers, carbon fibers, graphite fibers, aromatic polyamide fibers, boron fibers, alumina fibers, and cerium carbide fibers, defoaming agents, rheology modifiers, and flame retardants. , fillers, polymerization inhibitors, pigments, dyes, coupling agents, ion trapping agents, mold release agents, and the like. These other components may be used singly or in combination of two or more kinds in any combination.

[Use Ratio of Each Component] When the resin laminate of the present invention is produced, the use ratio of each component is not limited, and is as follows, for example.

When the cyanate compound is used as the curing agent, the ratio of the cyanate group number of the cyanate compound to the epoxy group of the epoxy resin in the resin composition (CN/Ep) is 0.7. The blending of ~2.5 is preferred. If the CN/Ep is in the range of 0.7 to 2.5, good flame retardancy and hardenability can be obtained.

[Method for Producing Resin Structure] The resin structure system of the present invention is produced by a process comprising the steps of: preparing an epoxy resin, a hardener, an optional inorganic filler, an optional hardening accelerator, and other optional components as necessary. In the curable resin composition, after the curable resin composition is cured to form a cured resin, at least one surface of the obtained cured resin is subjected to surface roughening treatment.

The method for preparing the curable resin composition is not limited, as long as it can uniformly mix the epoxy resin, the hardener, the inorganic filler as needed, the hardening accelerator as needed, and other components as necessary. Use any method. The following examples can be cited.

(i) introducing an epoxy resin into the reactor. When the epoxy resin is a solid, it is heated at a suitable temperature to become a liquid, in which an inorganic filler is added as needed to completely dissolve the hardener, and a hardener is added thereto as needed. A method of preparing a curable resin composition by adding a hardening accelerator, uniformly mixing it in a liquid state, and performing a defoaming treatment as needed. (ii) using a mixer, etc., using an epoxy resin, a curing agent, an optional inorganic filler, and a hardening accelerator and other components to be added as needed, and then using a hot roll, a twin-screw extruder, a kneader, etc. A method of performing melt-kneading to prepare a curable resin composition.

(iii) an epoxy resin, a curing agent, an optional inorganic filler, and optionally a hardening accelerator, and other components are dissolved in a solvent such as methyl ethyl ketone, acetone, or toluene to prepare a varnish-like curable resin composition. method.

Further, when a curing agent is added to a mixture of an epoxy resin and an optional inorganic filler, the curing reaction starts. Therefore, the step after the addition of the curing agent is preferably carried out as short as possible and rapidly.

The method of curing the curable resin composition to form a cured resin is not limited, and a curing method of the epoxy resin composition conventionally used can be arbitrarily selected. As the curing method, for example, a thermosetting method, an energy ray hardening method (electron beam curing method, ultraviolet curing method, etc.), a moisture curing method, or the like, a thermal curing method is preferable.

Specifically, when the curable resin composition is solid at normal temperature, it can be cured by a conventionally known molding method such as pulverization or tableting, followed by transfer molding, compression molding, or injection molding to produce a cured resin ( Hardened molded article).

On the other hand, when the curable resin composition is in the form of a liquid or a varnish at normal temperature, for example, a curable resin composition can be injected into a mold (forming), injected into a container (filling, etc.), and coated on a substrate. After hardening (stacking), impregnation with a fiber (fibril) or the like (such as filament wetting), the method is followed by heating and hardening to obtain a cured resin. In addition, it is a liquid or varnish-like curable resin composition at normal temperature, and if necessary, it is subjected to injection molding, charging, coating, impregnation with fibers, etc., and then heated and dried to be semi-hardened. (Phase B), the viscosity is reduced, and the workability is improved. Further, the curable resin composition of the present invention in the form of a varnish may be applied to a cast film by a coating device such as a comma coater, a die coater or a gravure coater, and dried. It is formed into a hardened film or can be used after vacuum defoaming.

When the curable resin composition is cured, the curing temperature and the curing time may vary depending on the type of the epoxy resin or the curing agent, and for example, a curing temperature of 20 to 250 ° C and a curing time of 1 to 24 hours may be employed.

[Protective Film] The resin laminate of the present invention may comprise a protective film laminated on the opposite side of the laser attenuating film on the resin insulating layer. The protective film prevents dust and dirt from adhering during the flow of the resin laminate until the resin film is laminated, and prevents the surface of the resin insulating layer from being physically damaged and protects the resin insulating layer. Examples of such a protective film include polyolefins such as polyethylene, polypropylene, and polyvinyl chloride, polyesters such as PET and PEN, and films such as PC and polyimide. Further, the protective film may be subjected to MAD treatment or corona treatment, or a mold release treatment may be applied. The thickness of the protective film may be any, for example, in the range of 5 to 30 μm. In order to distinguish it from the release film for laser attenuation, the protective film may be colored, and may also be described as a protective film.

[Manufacturing Method of Printed Circuit Board] Another aspect of the present invention relates to a method of manufacturing a multilayer printed wiring board using the resin laminate of the present invention. The method includes the steps of laminating the resin laminate of the present invention into a resin substrate having the substrate and the conductive circuit formed on the substrate, and the resin of the conductive substrate and the resin laminate of the circuit substrate The insulating layer becomes face to face. When a resin laminate in a semi-hardened state is used, a full hardening step may be included after lamination. The work of thermally hardening the resin insulating layer made of a thermosetting resin can be carried out by a conventional method. For example, a resin laminate is placed on one surface or both surfaces of a circuit board so that the resin insulating layer and the circuit board face each other, and the metal plate such as a SUS mirror plate is heated and pressurized, and laminated and pressed to be fully cured. The conditions at this time may be any conditions generally used in the technical field to which the present invention pertains and which can cure the thermosetting resin, and can be, for example, a pressure of 5 to 40 kgf/cm ² , a temperature of 120 to 180 ° C, and a temperature of 20 to 100. The squeeze time of minutes is carried out. Heating and pressurization may be performed by pressing a metal plate from the side of the plastic film with a heated SUS mirror plate or the like, but it is preferable not to directly press the metal plate, but to separate the circuit board from the circuit board. It is preferable that the elastic material such as the uneven heat-resistant rubber is pressed. The lamination step can also be carried out using a vacuum laminator. In this case, the resin laminate is heated and pressurized under reduced pressure, and the resin laminate is laminated on the circuit board. The conditions for lamination may be those generally used in the field, and may be carried out, for example, at a temperature of 70 to 140 ° C, a pressure in the range of 1 to 11 kgf/cm ² , and a reduced pressure of 20 mmHg (26.7 hPa) or less. After the laminating step, the laminated film can be smoothed by hot pressing using a metal plate. The lamination step and the smoothing step described above can be carried out continuously using a commercially available vacuum laminator. After the lamination step or after the smoothing step, a thermal hardening step can be performed. The heat hardening step thermally hardens the resin composition and forms an insulating layer. The thermosetting conditions vary depending on the type of the thermosetting resin composition, etc., but generally, the curing temperature is 170 to 190 ° C, and the curing time is 15 to 60 minutes.

Moreover, the method for producing a multilayer printed wiring board according to the present invention includes the step of irradiating a laser beam from the side of the release film for laser attenuation of the resin laminate on the laminated circuit board and the resin laminate. By irradiating the laser, a fine via hole penetrating the resin insulating layer can be formed. The size of the fine via hole is preferably such that the top diameter of the via hole is 30 μm or less and the difference between the top diameter and the bottom diameter is 10 μm or less.

There is no limit to the type of laser exposure. For example, carbon dioxide laser, YAG laser, excimer laser, and the like. Among them, carbon dioxide laser is preferred. The irradiated carbon dioxide laser generally uses a laser having a wavelength of 9.2 to 10.8 μm. Further, the number of shots may be one or more times, and the laser attenuation effect of the release film for laser attenuation is preferably one time, and even if it is performed a plurality of times, it is preferable to reduce the output after the second time. The cleaning emission is better. The output energy of the carbon dioxide laser can be appropriately set by a person skilled in the art in view of the thickness of the resin insulating layer, the thickness of the release film for laser attenuation, and the desired aperture. Generally, the thicker the thickness of the resin insulating layer and the thickness of the release film for laser attenuation, the higher the output energy of the necessary carbon dioxide laser. On the other hand, if the energy of the carbon dioxide laser is too low, the workability is lowered, and the bottom diameter is smaller than the top diameter. Therefore, the viewpoint of using a release film for laser attenuation having a thickness of more than 50 μm and/or the difference between the top diameter and the bottom diameter is 10 μm or less, and the output energy is, for example, 0.3 mJ or more, more preferably more than 0.6 mJ, and more. Good is 0.8mJ or more. On the other hand, from the viewpoint of suppressing the top diameter of 30 μm or less, the output energy is 5 mJ or less, and more preferably 3 mJ or less. The pulse width of the carbon dioxide laser is not particularly limited, and can be selected in a wide range of pulse waves of about 0.5 μs to 100 μs, but the viewpoint of suppressing the top diameter of 30 μm or less is preferable, and the upper limit is preferably 30 μs or less, more preferably 15 μs. the following.

The method of manufacturing the multilayer printed circuit board of the present invention may further comprise the step of peeling the release film from the resin layer after forming the via hole by laser irradiation. After the release film is peeled off, a roughening treatment step of roughening the surface of the resin insulating layer may be performed. The surface roughening treatment method is not limited, and may be appropriately selected depending on the type of the epoxy resin and the inorganic filler to be used, and examples thereof include ultraviolet irradiation treatment, plasma treatment, and solvent treatment. Any of these may be implemented singly or in combination of two or more kinds.

The ultraviolet irradiation treatment is performed by irradiating the surface of the cured resin with ultraviolet rays. The wavelength of the ultraviolet light is not particularly limited, but is usually 20 nm or more, preferably 50 nm or more, more preferably 100 nm or more, and usually 400 nm or less, preferably 350 nm or less, and more preferably 300 nm or less. The irradiation time of the ultraviolet rays is not limited, and is usually 2 minutes or longer, more preferably 5 minutes or longer, and usually 240 minutes or shorter, and more preferably 120 minutes or shorter.

The plasma treatment is performed by irradiating a surface of the cured resin with a plasma. The plasma is of any kind. For example, oxygen (oxygen plasma), argon (argon plasma), air (air plasma), nitrogen (nitrogen plasma) and other plasma. Any of these may be used singly or in combination of two or more kinds in any combination. The irradiation time of the plasma is not limited, but is usually 2 minutes or longer, preferably 5 minutes or longer, and usually 240 minutes or shorter, and preferably 120 minutes or shorter.

The solvent treatment is not limited, and examples thereof include an oxidation treatment using an acidic solvent, a reduction treatment using an alkaline solvent, and the like. Among them, the solvent treatment is preferably carried out by a solvent treatment including a swelling step, a surface roughening and a sludge dissolution step, and a neutralization step.

The swelling step is carried out by swelling the surface insulating layer with a swelling agent. The swelling agent is not limited as long as it can improve the moisture permeability of the surface insulating layer and swell the surface insulating layer until the next surface is roughened and the oxidative decomposition in the slag-dissolving step is promoted. For example, an alkali solution, a surfactant solution, and the like.

The surface roughening and the sludge dissolution step are carried out using an oxidizing agent. The oxidizing agent, for example, a permanganate solution or the like, is preferably a potassium permanganate aqueous solution or a sodium permanganate aqueous solution. The oxidant treatment is referred to as wet desmearing, but in addition to the wet degumming, it is also treated by plasma treatment, UV treatment for dry desmear, mechanical polishing with a buff, etc. Other known roughening treatments such as grinding are suitably combined and carried out.

The neutralization step is a step of neutralizing the oxidizing agent used in the previous step with a reducing agent. The reducing agent may, for example, be an amine-based reducing agent, and a specific example thereof may be an acidic reducing agent such as a hydroxylamine sulfate aqueous solution, an ethylenediaminetetraacetic acid aqueous solution or a nitrogen-based triacetic acid aqueous solution.

The method for manufacturing the multilayer printed circuit board of the present invention may be performed after the roughening treatment or without roughening treatment, and further includes a plating step of forming a conductor layer by plating on the surface of the resin insulating layer, and a conductor layer formed thereon A circuit forming (patterning) step of forming a circuit. These steps can be carried out in accordance with various conventionally known methods of manufacturing multilayer printed circuit boards.

The plating step can be performed by, for example, forming a conductor layer by a combination of electroless plating and electrolytic plating in a surface of an insulating layer formed by roughening treatment, or forming a conductor layer only by electroless plating. The conductor layer can be formed of a metal such as copper, aluminum, nickel, silver or gold or an alloy of such metals, and in particular copper is preferred. The copper plating layer may be formed by a combination of electroless copper plating and electrolytic copper plating, or a plating resist having a pattern opposite to that of the conductor layer, and plating only with electroless copper.

The circuit forming step may be a semi-additive method, a full additive method, a subtractive method, or the like. Among them, a semi-additive method is preferable in view of the viewpoint of forming a fine wiring pattern.

A method of forming a pattern by a semi-additive method, for example, after forming a thin conductor layer on the surface of an insulating layer by electroless plating or the like, selectively applying electrolytic plating (pattern plating) using a plating resist, and then plating A method in which a resist is peeled off and an entire amount is etched to form a wiring pattern.

A method of forming a pattern by a full-addition method, for example, a method of forming a pattern by using a plating resist on a surface of an insulating layer, and selectively attaching an electroless plating or the like to form a wiring pattern.

A method of forming a pattern by subtraction, for example, after forming a conductor layer by plating on the surface of the insulating layer, using a etch resist to selectively remove the conductor layer to form a wiring pattern.

When the wiring pattern is formed by plating, it is preferable to carry out the drying step after plating, from the viewpoint of improving the adhesion strength between the insulating layer and the conductor layer. When the pattern is formed by the semi-additive method, electroless plating and electrolytic plating are combined. However, in this case, it is preferred to perform drying after electroless plating and after electrolytic plating, respectively. The drying after electroless plating is preferably carried out at 80 to 180 ° C for 10 to 120 minutes, and the drying after electrolytic plating is preferably carried out at 130 to 220 ° C for 10 to 120 minutes.

The circuit board used in the manufacture of the multilayer printed circuit board of the present invention mainly refers to a substrate such as a glass epoxy substrate, a metal substrate, a polyester substrate, a polyimide substrate, a BT resin substrate, or a thermosetting polyphenylene ether substrate. A substrate on which a patterned conductor layer (circuit) is formed on one or both sides. Further, when manufacturing a multilayer printed circuit board, the inner layer circuit substrate further forming an intermediate layer of the insulating layer and/or the conductor layer is also included in the circuit substrate of the present invention. Moreover, the surface of the conductor layer (circuit) is roughened beforehand by blackening treatment or the like, and it is preferable from the viewpoint of the adhesion of the insulating layer to the circuit board. [Examples]

[Production of Cyanate Compound] Synthesis Example 1 Synthesis of α-naphthol aralkyl type cyanate compound (compound of formula (8)): [Chemical 8] (In the formula, the average 値 of n is 3~4.)

The reactor equipped with a thermometer, a stirrer, a dropping funnel and a reflux cooler was previously cooled to 0 to 5 ° C with brine, and 7.47 g (0.122 mol) of cyanogen chloride and 9.75 g of hydrochloric acid of 35% (0.0935 mol) were added thereto. ), 76 ml of water, and 44 ml of dichloromethane.

The temperature in the reactor was maintained at -5 to +5 ° C, the pH was 1 or less, and the α-naphthol aralkyl resin represented by the following formula (8') was added dropwise with a dropping funnel over 1 hour under stirring (SN485). , OH group equivalent: 214g / eq. Softening point: 86 ° C, Nippon Steel Chemical Co., Ltd.) 20g (0.0935mol), and triethylamine 14.16g (0.14mol) dissolved in dichloromethane 92ml solution After the completion of the dropwise addition, 4.72 g (0.047 mol) of triethylamine was added dropwise over 15 minutes. 【化9】 (In the formula, the average 値 of n is 3~4.)

After completion of the dropwise addition, the mixture was stirred at the same temperature for 15 minutes, and then the reaction liquid was separated and the organic layer was separated. The obtained organic layer was washed twice with 100 ml of water, and then the dichloromethane was evaporated under reduced pressure using an evaporator, and then concentrated and dried at 80 ° C for 1 hour to obtain α-naphthol represented by the above formula (8). A cyanate compound (α-naphthol aralkyl type cyanate compound) of an aralkyl resin was 23.5 g.

[Production of a resin composition] 47.5 parts by mass of a biphenyl aralkyl type epoxy resin (NC-3000-H, manufactured by Nippon Kayaku Co., Ltd.) represented by the formula (1) as an epoxy resin, and (22.7 parts by mass of epoxy resin naphthalene type epoxy resin (made by HP4710, DIC), and α-naphthol aralkyl type cyan represented by the formula (8) obtained as the cyanate compound in Synthesis Example 1. 51.4 parts by mass of a solution of a methyl ester (cyanate equivalent: 261 g/eq.) of methyl ester (cyanate equivalent: 261 g/eq.) (nonvolatile content: 50% by mass) (in terms of nonvolatile content: 25.7 parts by mass) The maleic imine compound (BMI-2300, manufactured by Daiwa Kasei Co., Ltd.) represented by the formula (9) of the maleic imine compound, 11.1 parts by mass, 2,4,5-triphenylimidazole as a hardening accelerator 300 parts by mass of PMA solution (manufactured by Wako Pure Chemical Industries, Ltd.) (3.0 parts by mass of nonvolatile matter) and MEK solution of zinc octoate (1% by mass of nonvolatile matter) 7 parts by mass The nonvolatile content was converted to 0.07 parts by mass in terms of dissolved or dispersed in MEK. Further, 125 parts by mass of magnesium oxide (SMO-0.4, manufactured by Seiko Chemical Co., Ltd., average particle diameter: 0.4 μm) as an inorganic filler was added, and stirred for 30 minutes using a high-speed stirring device to obtain a varnish (including an epoxy resin, A solution of a cyanate resin, a maleimide compound, or a resin composition of an inorganic filler. 【化10】 (wherein R ^{1 to 4} each independently represent a hydrogen atom or a methyl group, and n is in the range of 1 to 10 in terms of an average enthalpy.)

[Production of Resin Laminate] The obtained varnish was uniformly applied to a release surface of a PET film having a release layer by a die coater so that the thickness of the dried resin composition layer became 8 μm or 20 μm at 150 Dry at ~180 ° C for 3 minutes. Then, a polypropylene film having a thickness of 15 μm was wound into a roll shape while being bonded to the surface of the resin composition layer. The roll-shaped adhesive film was cut to a width of 507 mm to obtain a sheet-like adhesive film having a size of 507 × 336 mm.

[Formation of via hole in resin insulating layer] The adhesive film was temporarily attached to both sides of a copper clad laminate having a size of 510 × 340 mm and a thickness of 0.2 mm which was formed into a circuit (circuit conductor thickness: 18 μm), and Nichigo Morton (share) was used. The vacuum laminator was laminated on both surfaces under the conditions of a temperature of 130 ° C, a pressure of 10 kgf/cm ² , and a gas pressure of 5 mmHg or less, and was continuously subjected to hot pressing by a SUS mirror plate under the conditions of a temperature of 180 ° C and a pressure of 10 kgf / cm ² . Next, the PET film with the release layer attached thereto was thermally cured at 180 ° C for 30 minutes to form an insulating layer on both surfaces of the circuit board. After cooling to room temperature, the PET film with the release layer was not peeled off, but a carbon dioxide laser device (ML605GTWIII-H-5200U) made of Mitsubishi Electric Co., Ltd. was used for opening to form a blind via hole (assuming The top diameter is 20~30μm). Further, since the top diameter is assumed to be 20 to 30 μm, when the PET film with the release layer of this example is adhered, the diameter of the mask at the time of opening is 0.6 mm.

Example 1: Use of a PET film with a release layer of a total thickness of 75 μm A PET film having a release layer of a total thickness of 75 μm was used as a release film for laser attenuation, and uniformly coated to form a resin composition layer after drying. The thickness was 20 μm, and the opening was performed by the processing energy described in the column of Example 1 of Table 1.

Example 2: Use of a PET film with a release layer of a total thickness of 100 μm A PET film having a release layer of a total thickness of 100 μm was used as a release film for laser attenuation, and uniformly coated to form a resin composition layer after drying. The thickness was 20 μm, and the opening was performed by the processing energy described in the column of Example 2 of Table 1.

Example 3: Use of a PET film with a release layer of a total thickness of 125 μm A PET film having a release layer of a total thickness of 125 μm was used as a release film for laser attenuation, and uniformly coated to form a resin composition layer after drying. The thickness was 20 μm, and the opening was performed by the processing energy described in the column of Example 3 of Table 1.

Example 4: Use of a PET film with a release layer of a total thickness of 100 μm A PET film having a release layer of a total thickness of 100 μm was used as a release film for laser attenuation, and uniformly coated to form a resin composition layer after drying. The thickness was 8 μm, and the opening was performed by the processing energy described in the column of Example 1 of Table 1.

Example 5: Use of a PEN film with a release layer of a total thickness of 100 μm A PEN film having a release layer of a total thickness of 100 μm was used as a release film for laser attenuation, and uniformly coated to form a resin composition layer after drying. The thickness was 20 μm, and the opening was performed by the processing energy described in the column of Example 5 of Table 1.

Example 6: Magnesium oxide and cerium oxide were used as an inorganic filler in an amount of 75 parts by mass of magnesium oxide (SMO-0.4, manufactured by Seiko Chemical Co., Ltd., average particle diameter: 0.4 μm), and cerium oxide (SFP-130MC) 50. A varnish (a solution of a resin composition) was obtained in the same manner as the above-described resin composition, except that the varnish was blended as a varnish. The obtained varnish was used, and a PET film having a release layer of 100 μm in total thickness was used as a release film for laser attenuation, and the coating was uniformly applied so that the thickness of the dried resin composition layer became 20 μm, and the example of Table 1 was used. The processing energy described in column 6 is used to perform the opening.

Comparative Example 1: Use of a PET film with a release layer of a total thickness of 38 μm A PET film having a release layer of a total thickness of 38 μm was used as a release film for laser attenuation, and uniformly coated to form a resin composition layer after drying. The thickness was 20 μm, and the opening was performed by the processing energy described in the column of Comparative Example 1 of Table 1. (Mask diameter 0.4mm).

Comparative Example 2: Use of a PET film with a release layer of a total thickness of 50 μm A PET film having a release layer of a total thickness of 50 μm was used as a release film for laser attenuation, and uniformly coated to form a resin composition layer after drying. The thickness was 20 μm, and the opening was performed by the processing energy described in the column of Comparative Example 2 of Table 1. (Mask diameter 0.4mm).

Comparative Example 3: A PET film having a release layer of a total thickness of 188 μm was used. A PET film having a release layer of a total thickness of 188 μm was used as a release film for laser attenuation, and uniformly coated to form a resin composition layer after drying. The thickness was 20 μm, and the opening was performed by the processing energy described in the column of Comparative Example 3 of Table 1.

Comparative Example 4: Use of a PET film with a release layer of a total thickness of 38 μm A PET film having a release layer of a total thickness of 38 μm was used as a release film for laser attenuation, and uniformly coated to form a resin composition layer after drying. The thickness was 8 μm, and the opening was performed by the processing energy described in the column of Comparative Example 4 of Table 1 (mask diameter: 0.4 mm).

Comparative Example 5: A resin composition having a low peeling strength as a resin composition, and a biphenyl aralkyl type epoxy resin (NC-3000-H, manufactured by Nippon Kayaku Co., Ltd.) And naphthalene type epoxy resin (made by HP4710, DIC) to 60.2 parts by mass of bisphenol A type epoxy resin (EPIKOTE 1001, manufactured by Mitsubishi Chemical Corporation), and without inorganic filler, Other than the above resin composition, a varnish (a solution of a resin composition) was obtained. The obtained varnish was used, and a PET film having a release layer of 75 μm in total thickness was used as a release film for laser attenuation, and the coating was uniformly applied so that the thickness of the dried resin composition layer became 20 μm, and the comparative example of Table 1 was used. The processing energy described in column 5 is used to perform the opening.

(Wet Roughening Treatment and Conductor Layer Plating) After performing laser opening in Examples 1 to 6 and Comparative Examples 1 to 5, the PET film with the release layer was peeled off, and an insulating layer which was also subjected to desmear treatment was performed. Surface treatment. The surface treatment is treated by the above-mentioned village industrial degumming treatment (swelling: Appdes MDS-37, roughening: Appdes MDE-40 and Appdes ELC-SH, neutralization: Appdes MDN-62), by swelling 60 ° C × 5 The procedure of minute, roughening 70 ° C × 20 minutes, neutralization 35 ° C × 5 minutes was carried out. The electroless copper plating treatment (using the chemical liquid name: MCD-PL, MDP-2, MAT-SP, MAB-4-C, MEL-3-APEA ver. 2) manufactured by the above-mentioned village industry is implemented to be about 0.5 μm. Electrolytic copper plating was carried out at 130 ° C for 1 hour. In Comparative Example 5, swelling occurred in the electroless copper plating layer after drying, and the subsequent evaluation could not be performed. Then, electrolytic copper plating was carried out so that the thickness of the plated copper became 18 μm, and drying was performed at 180 ° C for 1 hour.

(Measurement method) 1) Measurement of the top diameter and the bottom diameter of the through hole The blind through hole was observed with a digital microscope (VHX-2000 manufactured by Keyence), and the diameter of the top and the diameter of the bottom of the through hole were measured at a diameter of 3 o'clock. And ask for an average. The results are shown in Table 1. 2) Plating copper adhesion A laminated plate on which copper plating has been applied is prepared, measured three times in accordance with JIS C6481, and averaged as the adhesion of the plated copper. The sample which was swollen during drying after electrolytic copper plating was evaluated using an unexpanded portion. The results are shown in Table 1. 【Table 1】

In Example 2 and Comparative Example 1, after the formation of the via hole, the resin laminate was cut, and the cut-off cross section of the via hole was taken. The results are shown in Fig. 2A (Comparative Example 1) and B (Example 2).

1‧‧‧Resin insulation
2‧‧‧Release film for laser attenuation
3‧‧‧Interlayer hole
4‧‧‧ top diameter
5‧‧‧ bottom diameter
6‧‧‧ Push

Figure 1 is a schematic diagram showing the laser intensity distribution of a carbon dioxide laser. In Fig. 2, Fig. 2A is a cross-sectional view showing a resin sheet subjected to laser processing on a resin sheet composed of a resin insulating layer having a thickness of 20 μm. 2B is a cross-sectional view showing the resin laminate after laser processing from the release film side for a resin laminate including a resin insulating layer having a thickness of 20 μm and a release film having a thickness of 100 μm.

no

1‧‧‧Resin insulation

2‧‧‧Release film for laser attenuation

3‧‧‧Interlayer hole

4‧‧‧ top diameter

5‧‧‧ bottom diameter

6‧‧‧ Push

Claims (17)

A resin laminate comprising a resin insulating layer for forming a fine via hole and a resin laminate for a printed wiring board laminated on the resin insulating layer for laser attenuation, and a release film The thickness exceeds 50 μm and is 180 μm or less. The resin laminate according to claim 1, wherein the release film for laser attenuation is formed of polyester. The resin laminate according to claim 2, wherein the polyester is selected from the group consisting of polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polynaphthalene. One or more of the group consisting of butylene glycol dicarboxylate (PBN), polybutylene terephthalate (PBT), and polytrimethylene terephthalate (PTT). The laminate according to any one of claims 1 to 3, wherein a top diameter of the via hole formed in the resin insulating layer is 30 μm or less, and a difference between the top diameter and the bottom diameter is 10 μm or less. The resin laminate according to any one of claims 1 to 3, wherein the resin insulating layer has a thickness of 3 to 50 μm. The resin laminate according to any one of claims 1 to 3, wherein the resin insulating layer is formed of a thermosetting resin composition. The resin laminate according to claim 6, wherein the thermosetting resin composition contains an epoxy resin, a cyanate compound, and an inorganic filler. The resin laminate according to item 6 of the patent application is obtained by semi-hardening the thermosetting resin composition. The resin laminate according to any one of claims 1 to 3, wherein the resin insulating layer has a plating peel strength of 0.4 kN/m or more. A method of manufacturing a multilayer printed circuit board comprising the steps of: applying a resin laminate according to any one of claims 1 to 9 to a circuit substrate having a substrate and a conductive circuit formed on the substrate Laminated so that the conductive circuit of the circuit board and the resin insulating layer of the resin laminate face each other, and the resin is formed to penetrate from the side of the release film for laser attenuation of the resin laminate to the resin The via hole of the insulating layer is peeled off from the resin insulating layer. The method of manufacturing a multilayer printed circuit board according to claim 10, wherein the resin laminate is a resin laminate according to claim 8 of the patent application, and the circuit substrate and the resin laminate are laminated Thereafter, the step of completely hardening the resin insulating layer in a semi-hardened state is further included before the formation of the via hole. A method of manufacturing a multilayer printed circuit board according to claim 10 or 11, wherein the laser is a carbon dioxide laser. The method of manufacturing a multilayer printed circuit board according to claim 12, wherein the energy of the laser is 0.3 mJ to 5 mJ. The method of manufacturing a multilayer printed wiring board according to claim 10, wherein a diameter of a top portion of the via hole formed in the resin insulating layer is 30 μm or less, and a difference between the top diameter and the bottom diameter is 10 μm or less. The method for manufacturing a multilayer printed circuit board according to claim 10, wherein after the release film is peeled off, the method further comprises the steps of: roughening the surface of the resin insulating layer and roughening the surface A conductor layer is formed by plating, and the conductor layer is patterned to form a circuit. A multilayer printed circuit board obtained by the method of manufacturing a multilayer printed circuit board according to any one of claims 10 to 15. A multilayer printed circuit board comprising a substrate having a substrate and a conductive circuit formed on the substrate, and a resin laminate laminated to the circuit substrate according to any one of claims 1 to 9. The resin insulating layer has a via hole formed by laser, and the top diameter of the via hole is 30 μm or less, and the difference between the top diameter and the bottom diameter is 10 μm or less.