JP2007273616A - Manufacturing method for multilayer printed circuit board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method for a multilayer printed circuit board, having even a superior laminating properties, when a resin composition is laminated on a circuit board in the form of a sheet-shaped laminating material, such as an adhesive film, a prepreg, in the formation of the multilayer printed circuit board having the superior heat resistance and mechanical strength for an insulating layer and having a low coefficient of thermal expansion and the formation for the insulating layer. <P>SOLUTION: The manufacturing method for the multilayer printed circuit board contains a process for forming the insulating layer on the circuit board and the process for forming a conductor layer on the insulating layer. In the manufacturing method for the multilayer printed circuit board, the insulating layer is formed by laminating the resin composition, containing (A) the polymer of a bismaleimide compound and a diamine compound, (B) an epoxy resin having two or more of epoxy groups in one molecule, (C) a curing agent, (D) a polyether sulfonic acid and (E) an inorganic filler on the circuit board, in a form of the sheet-shaped laminating material and subjected to thermosetting of the laminate. In the manufacturing method, the conductor layer is formed on a roughened surface, obtained by roughening the surface of the insulating layer by an oxidant through copper plating. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a multilayer printed wiring board, in which an insulating layer formed of a sheet-like laminated material is roughened with an oxidizing agent, and a conductor layer is formed by plating.

  In recent years, downsizing and higher performance of electronic devices have progressed, and multilayering of printed wiring boards and higher density of wiring have progressed. As the number of layers increases, it is necessary to reduce the thickness of the printed wiring board while maintaining the mechanical strength (strength at break and elongation at break). In addition, in order to maintain connection reliability in increasing the density of wiring, the material forming the insulating layer is required to have high heat resistance. In addition, multilayer printed wiring boards with high-density wiring tend to cause problems such as cracking due to the difference in thermal expansion coefficient between copper wiring and insulating layer, so it is required to keep the thermal expansion coefficient of insulating layer low. The

  As a multilayer printed wiring board excellent in mechanical strength and heat resistance, for example, Patent Document 1 discloses a heat-resistant resin such as a solvent-soluble polyamideimide resin, a thermosetting resin such as an epoxy resin, a filler, a resin having a polybutadiene skeleton, and the like. The method of using the resin composition which consists of as an insulating layer is disclosed. Patent Document 2 discloses a method in which a resin composition comprising a maleimide compound, an epoxy resin, a curing agent, and an aromatic polymer is used as an insulating layer.

  However, when a resin composition that is generally excellent in mechanical strength and heat resistance is used as a sheet-like laminated material such as an adhesive film or prepreg, and the resin composition is laminated or used on a circuit board in a dry or semi-cured state, There was a problem that the property became low. For example, in patent document 1, in order to laminate an adhesive film on a circuit board with a vacuum laminator, a resin composition layer that can be laminated on the adhesive film is newly provided. However, the adhesive film having such a two-layer structure is unavoidably deteriorated in performance because the mechanical strength of the resin composition layer that can be laminated becomes relatively low. Further, it is disadvantageous in terms of manufacturing cost and thickness reduction.

JP 2005-39247 A JP-A-11-140281

  The present invention provides a method for producing a multilayer printed wiring board having excellent heat resistance and mechanical strength of an insulating layer and having a low coefficient of thermal expansion. Further, in the formation of an insulating layer, a sheet-like laminated material such as an adhesive film or prepreg is used. When a resin composition is laminated on a circuit board in a form, it is to provide a method for producing a multilayer printed wiring board that is excellent in laminating properties.

  As a result of intensive research by the present inventors, after laminating the resin composition in the form of a sheet-like laminated material on a circuit board, an insulating layer is formed by thermosetting, and the surface of the insulating layer is further roughened with an oxidizing agent. When a conductor layer is formed on the roughened surface by plating, the resin composition is a polymer of a bismaleimide compound and a diamine compound, an epoxy resin having two or more epoxy groups in one molecule, a curing agent, and a polyether. By using a resin composition containing a sulfone resin and an inorganic filler, it has been found that the above problems can be solved, and the present invention has been completed.

That is, the present invention includes the following contents.
[1] A method for producing a multilayer printed wiring board comprising a step of forming an insulating layer on a circuit board and a step of forming a conductor layer on the insulating layer, wherein the insulating layer comprises (A) a bismaleimide compound and Polymer composition of diamine compound, (B) epoxy resin having two or more epoxy groups in one molecule, (C) curing agent, (D) polyethersulfone resin and (E) inorganic filler Is formed by laminating on a circuit board in the form of a sheet-like laminated material and then thermosetting, and the conductor layer is formed by plating on a roughened surface obtained by roughening the surface of the insulating layer with an oxidizing agent. A method for producing a multilayer printed wiring board, comprising:
[2] The sheet-like laminated material is an adhesive film in which the resin composition is layered on the support film, an adhesive film with copper foil in which the resin composition is layered on the copper foil, or the resin composition is made of fibers. The method according to [1] above, which is a prepreg impregnated in a sheet-like reinforcing substrate.
[3] The sheet-like laminated material is an adhesive film in which the resin composition is formed on the support film, and the insulating layer is formed by laminating the adhesive film on the circuit board and then peeling the support film to form the resin composition. The method according to [1] above, wherein the product is formed by heat-curing or peeling the support film after curing the resin composition.
[4] When the nonvolatile content of the resin composition is 100% by mass, the content of the component (A) is 10 to 50% by mass, the content of the component (B) is 15 to 45% by mass, and the component (C) Any of the above [1] to [3], wherein the content is 3 to 20% by mass, the content of the component (D) is 10 to 50% by mass, and the content of the component (E) is 10 to 50% by mass. The method described in 1.
[5] The resin composition further contains (F) one or more resins selected from the group consisting of polyimide resins, polyamideimide resins, polyamide resins, polyetherimide resins, polybenzoxazole resins, and polybenzimidazole resins. The method according to any one of [1] to [4] above.
[6] The method according to [5] above, wherein the content of the component (F) is 1 to 10% when the nonvolatile content of the resin composition is 100% by mass.
[7] The method according to [5] or [6] above, wherein the resin of component (F) is a polyamideimide resin.
[8] The method according to any one of [1] to [7] above, wherein the oxidizing agent is an alkaline permanganate solution.

  According to the production method of the present invention, a multilayer printed wiring board having an insulating layer having excellent heat resistance and mechanical strength and having a low coefficient of thermal expansion is provided. Moreover, since the sheet-like laminated material used in the method of the present invention is excellent in laminating properties, a multilayer printed wiring board can be efficiently produced.

  Hereinafter, the present invention will be described in more detail.

[Component (A) Bismaleimide Compound and Diamine Compound Polymer]
The polymer of the component (A) bismaleimide compound and diamine compound in the present invention can be obtained by Michael addition reaction of an aromatic or aliphatic primary diamine compound or secondary diamine compound to a bismaleimide compound. it can.

  As the bismaleimide compound, an aromatic bismaleimide compound having an aromatic ring structure is preferable from the viewpoint of heat resistance and thermal expansion coefficient. Preferred bismaleimide compounds include N, N ′-(1,3-phenylene) bismaleimide, N, N ′-(1,4-phenylene) bismaleimide, N, N ′-[1,3- (2- Methylphenylene)] bismaleimide, bis (4-maleimidophenyl) methane, bis (3-methyl-4-maleimidophenyl) methane, bis [4- (4-maleimidophenoxy) phenyl] methane, bis (3-ethyl-5 -Methyl-4-maleimidophenyl) methane, 1,1-bis [4- (3-maleimidophenoxy) phenyl] ethane, 1,1-bis [4- (4-maleimidophenoxy) phenyl] ethane, 1,2- Bis [4- (3-maleimidophenoxy) phenyl] ethane, 1,2-bis [4- (4-maleimidophenoxy) phenyl] ethane, 2,2-bis [4 (4-maleimidophenoxy) phenyl] propane, 2,2-bis [4- (3-maleimidophenoxy) phenyl] butane, 2,2-bis [4- (4-maleimidophenoxy) phenyl] butane, 1,4- Bis (4-maleimidophenyl) cyclohexane, 1,4-bis (maleimidomethyl) benzene, 1,3-bis (3-maleimidophenoxy) benzene, 1,4-bis [4- (4-maleimidophenoxy) -α, α-dimethylbenzyl] benzene, 1,3-bis [4- (4-maleimidophenoxy) -α, α-dimethylbenzyl] benzene, 1,4-bis [4- (3-maleimidophenoxy) -α, α- Dimethylbenzyl] benzene, 1,3-bis [4- (3-maleimidophenoxy) -α, α-dimethylbenzyl] benzene, 1,4-bis 4- (4-Maleimidophenoxy) -3,5-dimethyl-α, α-dimethylbenzyl] benzene, 1,3-bis [4- (4-maleimidophenoxy) -3,5-dimethyl-α, α-dimethyl Benzyl] benzene, 1,4-bis [4- (3-maleimidophenoxy) -3,5-dimethyl-α, α-dimethylbenzyl] benzene, 1,3-bis [4- (3-maleimidophenoxy) -3 , 5-dimethyl-α, α-dimethylbenzyl] benzene, 4,4′-bis (3-maleimidophenoxy) biphenyl, 4,4′-bis (4-maleimidophenoxy) biphenyl, bis (4-maleimidophenyl) ketone Bis [4- (3-maleimidophenoxy) phenyl] ketone, bis [4- (4-maleimidophenoxy) phenyl] ketone, bis (4-maleimi Phenyl) sulfide, bis [4- (3-maleimidophenoxy) phenyl] sulfide, bis [4- (4-maleimidophenoxy) phenyl] sulfide, bis [4- (3-maleimidophenoxy) phenyl] sulfoxide, bis [4- (4-maleimidophenoxy) phenyl] sulfoxide, bis (4-maleimidophenyl) sulfone, bis [4- (3-maleimidophenoxy) phenyl] sulfone, bis [4- (4-maleimidophenoxy) phenyl] sulfone, bis (4 -Maleimidophenyl) ether, bis [4- (3-maleimidophenoxy) phenyl] ether, bis [4- (4-maleimidophenoxy) phenyl] ether and the like. Each of the bismaleimide compounds may be used alone or in combination of two or more.

  As the diamine compound, a primary diamine compound is preferable from the viewpoint of reactivity with the bismaleimide compound, and an aromatic diamine compound having an aromatic ring structure is preferable from the viewpoint of heat resistance and thermal expansion coefficient. Preferred diamine compounds include 3,3′-diaminobenzophenone, 4,4′-diaminobenzophenone, 3,3′-diaminodiphenyl ether, 4,4′-diaminodiphenyl ether, and 4,4′-bis (3-aminophenoxy). Biphenyl, 4,4′-bis (4-aminophenoxy) biphenyl, 3-bis (3-aminophenoxy) benzene, 4-bis (4-aminophenoxy) benzene, bis (3- (3-aminophenoxy) phenyl) Ether, bis (4- (4-aminophenoxy) phenyl) ether, 3-bis (3- (3-aminophenoxy) phenoxy) benzene, 4-bis (4- (4-aminophenoxy) phenoxy) benzene, bis ( 3- (3- (3-aminophenoxy) phenoxy) phenyl) ether, bis ( -(4- (4-aminophenoxy) phenoxy) phenyl) ether, 3-bis (3- (3- (3-aminophenoxy) phenoxy) phenoxy) benzene, 4-bis (4- (4- (4-amino Phenoxy) phenoxy) phenoxy) benzene, 2-bis [4- (3-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 4′-bis (3-amino) Benzyl) biphenyl, 4′-bis (4-aminobenzyl) biphenyl, 3-bis (3-aminobenzyl) benzene, 4-bis (4-aminobenzyl) benzene, 3-bis (α, α-dimethyl-3-) Aminobenzyl) benzene, 1,4-bis (α, α-dimethyl-3-aminobenzyl) benzene, 3-bis (α, α-dimethyl-4-aminobenzene) Jill) benzene, and the like. The diamine compounds may be used alone or in combination of two or more.

  The reaction between the bismaleimide compound and the diamine compound can be carried out according to a known method (see JP-A-3-14836, etc.). The amount of the diamine compound used is preferably 1 to 4 molar equivalents, more preferably 2 to 3.5 molar equivalents, relative to 1 mol of the bismaleimide compound. The reaction is usually carried out by reacting in the range of 100 to 250 ° C., preferably 170 ° C. to 200 ° C. for several minutes to several hours. Examples of the solvent used for the reaction include polar solvents such as N, N-dimethylformamide and N-methylpyrrolidone. In order to control the reaction rate, a radical scavenger, an anionic polymerization catalyst, a radical generator, a Michael addition reaction accelerator or the like can be used as a catalyst as necessary. The addition amount of the catalyst is usually 0.001 to 5% by mass with respect to the total mass of the bismaleimide compound and the diamine compound.

  The mass average molecular weight of the polymer of the bismaleimide compound and the diamine compound is preferably 600 to 3500 from the viewpoint of solubility in organic solvents and mechanical strength. In addition, the mass mean molecular weight in this invention is measured by the gel permeation chromatography (GPC) method (polystyrene conversion). Specifically, the number average molecular weight by the GPC method is LC-9A / RID-6A manufactured by Shimadzu Corporation as a measuring device, and Shodex K-800P / K-804L / K manufactured by Showa Denko KK as a column. -804L can be measured using chloroform as a mobile phase at a column temperature of 40 ° C. and calculated using a standard polystyrene calibration curve. The softening point of the resin composition is preferably 40 to 150 ° C. from the viewpoint of laminating properties.

  Examples of commercially available polymers of bismaleimide compounds and diamine compounds include “Techmite E2020” (N, N ′-(4,4′-diphenylmethane) bismaleimide and 1,3 manufactured by Printec Co., Ltd. -A polymer of bis (α, α-dimethyl-4-aminobenzyl) benzene, a weight average molecular weight of 1500 to 2000, and a softening point of 103 to 118 ° C.

  The content of the polymer of the bismaleimide compound and the diamine compound is preferably 10 to 50% by mass when the nonvolatile content of the resin composition of the present invention is 100% by mass. A polymer of a bismaleimide compound and a diamine compound may be used alone or in combination of two or more.

[Epoxy resin having two or more epoxy groups in one molecule of component (B)]
The “epoxy resin having two or more epoxy groups in one molecule” of the component (A) in the present invention is an aromatic epoxy resin having an aromatic ring skeleton in the molecule from the viewpoint of thermal expansion coefficient and heat resistance. preferable. Preferred epoxy resins include, for example, cresol novolac type epoxy resins, phenol novolac type epoxy resins, tert-butyl-catechol type epoxy resins, biphenyl type epoxy resins, naphthalene type epoxy resins (including naphthol novolak type epoxy resins), and bisphenol A. Type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, fluorene type epoxy resin, xanthene type epoxy resin, dicyclopentadiene type epoxy resin, anthracene type epoxy resin. The epoxy resins may be used alone or in combination of two or more.

  The epoxy resin as component (B) preferably contains an epoxy resin that is liquid at a temperature of 20 ° C. from the viewpoint of laminating properties and mechanical strength. The content of the liquid epoxy resin is preferably 20 to 100% by mass when the epoxy resin of the component (B) is 100% by mass.

  Examples of commercially available liquid epoxy resins include HP4032 (naphthalene type epoxy resin, epoxy equivalent 149), HP4032D (naphthalene type epoxy resin, epoxy equivalent 141) manufactured by Dainippon Ink and Chemicals, Japan epoxy resin ( Epicoat 807 (bisphenol F type epoxy resin, epoxy equivalent 170), Epicoat 828EL (bisphenol A type epoxy resin, epoxy equivalent 189)), Epicoat 152 (phenol novolac type epoxy resin, epoxy equivalent 174), etc. .

  Examples of commercially available solid epoxy resins include HP4700 (naphthalene type epoxy resin, epoxy equivalent 163), N-690 (cresol novolak type epoxy resin, epoxy equivalent 208) manufactured by Dainippon Ink and Chemicals, N-695 (cresol novolac type epoxy resin, epoxy equivalent 208), Nippon Kayaku Co., Ltd. EPPN-502H (trisphenol epoxy resin, epoxy equivalent 168), NC7000L (naphthol novolak type epoxy resin, epoxy equivalent 228), NC3000H (Biphenyl type epoxy resin, epoxy equivalent 290), ESN185 manufactured by Tohto Kasei Co., Ltd. (naphthol novolak type epoxy resin, epoxy equivalent 275), ESN475 (naphthol novolak type epoxy resin, epoxy equivalent 350), etc. It is.

  The content of the epoxy resin is preferably 15 to 45% by mass, more preferably 20 to 40% by mass, particularly preferably 25 when the nonvolatile content of the resin composition in the present invention is 100% by mass. It is -35 mass%.

[Curing agent for component (C)]
As the curing agent of the component (C) in the present invention, an amine curing agent, a guanidine curing agent, an imidazole curing agent, a phenol curing agent, an acid anhydride curing agent, a hydrazide curing agent, a carboxylic acid curing agent. And thiol-based curing agents or epoxy adducts or microcapsules thereof. A phenolic curing agent is particularly preferable as the curing agent. Examples of phenolic curing agents include phenol novolac resins, alkylphenol novolak resins, triazine structure-containing phenol novolak resins, bisphenol A novolak resins, dicyclopentadiene structure-containing phenol resins, xylok type phenol resins, terpene-modified phenol resins, Examples thereof include polyvinylphenols, naphthalene structure-containing phenolic curing agents, fluorene structure-containing phenolic curing agents, and the like. Specific examples of commercially available phenolic curing agents include “Phenolite LA7054” and “Phenolite EXB9889” manufactured by Dainippon Ink & Chemicals, Inc. Each of the curing agents may be used alone or in combination of two or more.

  The content of the curing agent of the component (C) is preferably 3 to 20% by mass and more preferably 6 to 15% by mass when the nonvolatile content of the resin composition of the present invention is 100% by mass. preferable. When the content of the curing agent is outside this range, the thermal expansion coefficient tends to increase or the mechanical strength tends to decrease.

  If necessary, an organic phosphine compound such as triphenylphosphine, an imidazole compound such as 2-ethyl 4-methylimidazole, and the like may be added to the resin composition of the present invention as a curing accelerator. When using a hardening accelerator, it is preferable to use it in the range of 0.5-2 mass% when the compounding quantity is 100 mass%.

[Polyethersulfone resin of component (D)]
The polyethersulfone resin of component (D) in the present invention is not particularly limited as long as it is a polyethersulfone resin that is dissolved in an organic solvent and has a functional group capable of crosslinking with an epoxy resin such as a hydroxyl group or a carboxy group at the terminal. A polyethersulfone resin that cannot be dissolved in an organic solvent is difficult to use in the present invention because it cannot be mixed with other components to prepare a composition. Although the organic solvent is not particularly limited, those having properties of being liquid at room temperature of 20 to 30 ° C. and dissolving the polyethersulfone resin are used due to the properties of the present invention. Preferred organic solvents include ketones such as acetone, methyl ethyl ketone and cyclohexanone, acetates such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate and carbitol acetate, and carbitols such as cellosolve and butyl carbitol. And aromatic hydrocarbons such as toluene and xylene, N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone and the like. These organic solvents may be used in combination of two or more.

  Examples of commercially available polyethersulfone resins include “PES5003P” manufactured by Sumitomo Chemical Co., Ltd., “P1700” and “P3500” manufactured by Solven Advanced Polymers Co., Ltd.

  The content of the polyethersulfone resin is preferably 10 to 50% by mass and more preferably 15 to 30% by mass when the nonvolatile content of the resin composition of the present invention is 100% by mass. When the content of the component (C) is too small, the coefficient of thermal expansion tends to increase and the mechanical strength tends to decrease. On the other hand, when the content is too large, the laminating property tends to be lowered.

[Inorganic filler of component (E)]
Examples of the inorganic filler in the present invention include silica, alumina, barium sulfate, talc, clay, mica powder, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum borate, and titanium. Examples thereof include barium acid, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, barium zirconate, and calcium zirconate. The inorganic fillers may be used alone or in combination of two or more. Silica is particularly preferred as the inorganic filler. The average particle size of the inorganic filler is preferably 1 μm or less, more preferably 0.8 μm or less, and particularly preferably 0.7 μm or less. When the average particle diameter exceeds 1 μm, the peel strength of the conductor layer formed by plating tends to decrease. If the average particle size of the inorganic filler is too small, when the epoxy resin composition is used as a resin varnish, the viscosity of the varnish tends to increase and the handleability tends to decrease. It is preferable that it is 05 μm or more. The inorganic filler is preferably surface-treated with a surface treatment agent such as a silane coupling agent in order to improve moisture resistance.

  The average particle diameter of the inorganic filler can be measured by a laser diffraction / scattering method based on Mie scattering theory. Specifically, the particle size distribution of the inorganic filler can be created on a volume basis by a laser diffraction particle size distribution measuring device, and the median diameter can be measured as the average particle diameter. As the measurement sample, an inorganic filler dispersed in water by ultrasonic waves can be preferably used. As a laser diffraction type particle size distribution measuring apparatus, LA-500 manufactured by Horiba, Ltd. can be used.

  The content of the inorganic filler is preferably 10 to 50% by mass and more preferably 20 to 40% by mass when the nonvolatile content of the resin composition in the present invention is 100% by mass.

[One or more kinds of resins selected from the group consisting of polyimide resin, polyamideimide resin, polyamide resin, polyetherimide resin, polybenzoxazole resin and polybenzimidazole resin of component (F)]
The resin composition of the present invention is selected from the group consisting of polyimide resin, polyamideimide resin, polyamide resin, polyetherimide resin, polybenzoxazole resin and polybenzimidazole resin as component (F) in order to further increase the mechanical strength. One or more kinds of resins may be contained. Polyamideimide resin is particularly preferable. These resins are not particularly limited as long as they are resins that dissolve in organic solvents. A resin that cannot be dissolved in an organic solvent is difficult to use because it cannot be mixed with other components to prepare a composition. The organic solvent is not particularly limited, and examples thereof include the same solvents as in the case of the polyethersulfone resin.

  Examples of commercially available resins of component (F) include soluble polyimides “Rika Coat SN20” and “Rika Coat PN20” manufactured by Shin Nippon Rika Co., Ltd., polyetherimide “Nippon GE Plastics Co., Ltd.” "Ultem", polyamideimide "Vilomax HR11NN" and "Vilomax HR16NN" manufactured by Toyobo Co., Ltd., polyimide resin "Neoprim C-1210" manufactured by Mitsubishi Gas Chemical Co., Ltd., polyamide manufactured by Hitachi Chemical Co., Ltd. Examples thereof include imide “KS-9300”.

  The content of the component (F) resin is preferably 1 to 10% when the nonvolatile content of the resin composition of the present invention is 100% by mass. When the content of the component (F) is too large, the laminate property tends to be lowered.

  The resin composition of the present invention may contain components other than those described above as long as the effects of the present invention are exhibited. For example, a radical polymerization initiator such as dicumyl peroxide and an aromatic carboxylic acid such as benzoic acid may be added as a curing catalyst. The addition amount in this case is preferably in the range of 0.001 to 5% by mass with respect to 100% by mass of the polymer of the bismaleimide compound and the diamine compound. Further, for example, an inorganic filler such as silica may be contained for the purpose of further reducing the coefficient of thermal expansion. When an inorganic filler is contained, the blending amount may be appropriately adjusted within a range that does not cause inconvenience in drilling workability such as via holes. Moreover, for example, other resin components such as a thermoplastic resin such as a phenoxy resin and polyvinyl acetal may be contained. In addition, for example, for the purpose of imparting flame retardancy, a flame retardant such as an organic phosphorus flame retardant, an organic nitrogen-containing phosphorus compound, a nitrogen compound, a silicone flame retardant, or a metal hydroxide may be contained. Also, for example, organic fillers such as silicon powder, nylon powder and fluorine powder, thickeners such as olben and benton, silicone type, fluorine type, polymer type antifoaming agent or leveling agent, imidazole type, thiazole type, triazole type Further, an adhesiveness-imparting agent such as a silane coupling agent, or a resin additive such as a colorant such as phthalocyanine / blue, phthalocyanine / green, iodin / green, disazo yellow, or carbon black may be contained.

  The total content of components (A) to (D) in the resin composition of the present invention is not particularly limited, but is usually 50 to 50% with respect to the resin composition (non-volatile content: 100% by mass). The range is 100% by mass.

  The resin composition in the present invention is, for example, applied on a support film to form a resin composition layer to form an adhesive film, or a sheet-like reinforcing substrate made of fibers impregnated with the resin composition to form a prepreg For example, it is used for forming an insulating layer in the form of a sheet-like laminated material.

  The adhesive film of the present invention is prepared by a method known to those skilled in the art, for example, by preparing a resin varnish in which a resin composition is dissolved in an organic solvent, applying the resin varnish using the support film as a support, and further heating or hot air. The organic solvent can be dried by spraying or the like to form a resin composition layer.

  Examples of the organic solvent include ketones such as acetone, methyl ethyl ketone and cyclohexanone, acetates such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate and carbitol acetate, and carbitols such as cellosolve and butyl carbitol. And aromatic hydrocarbons such as toluene and xylene, N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone and the like. Two or more organic solvents may be used in combination.

  The drying conditions are not particularly limited, but the drying is performed so that the content of the organic solvent in the resin composition layer is usually 10% by mass or less, preferably 5% by mass or less. Depending on the amount of the organic solvent in the varnish and the boiling point of the organic solvent, for example, a varnish containing 30 to 60% by mass of the organic solvent can be dried at 50 to 150 ° C. for about 3 to 10 minutes. Those skilled in the art can appropriately set suitable drying conditions through simple experiments.

  The thickness of the resin composition layer formed in the adhesive film is usually not less than the thickness of the conductor layer. Since the thickness of the conductor layer of the circuit board is usually in the range of 5 to 70 μm, the thickness of the resin composition layer is preferably 10 to 100 μm. The resin composition layer may be protected by a protective film described later. By protecting with a protective film, it is possible to prevent dust and the like from being attached to the surface of the resin composition layer and scratches.

  Examples of the support film and protective film in the present invention include polyolefins such as polyethylene, polypropylene, and polyvinyl chloride, polyethylene terephthalate (hereinafter sometimes abbreviated as “PET”), polyesters such as polyethylene naphthalate, polycarbonate, polyimide, Can include release paper, copper foil, metal foil such as aluminum foil, and the like. In addition, the support film and the protective film may be subjected to a release treatment in addition to the mud treatment and the corona treatment.

  Although the thickness of a support film is not specifically limited, Usually, it is 10-150 micrometers, Preferably it is used in 25-50 micrometers. The thickness of the protective film is not particularly limited, but is usually 1 to 40 μm, preferably 10 to 30 μm.

  Next, the manufacturing method of the multilayer printed wiring board of this invention using an adhesive film is demonstrated. When the resin composition layer is protected with a protective film, the resin composition layer is peeled and then laminated on one or both sides of the circuit board so that the resin composition layer is in direct contact with the circuit board. In the adhesive film of the present invention, a method of laminating on a circuit board under reduced pressure by a vacuum laminating method is preferably used. The laminating method may be a batch method or a continuous method using a roll. Further, the adhesive film and the circuit board may be heated (preheated) as necessary before lamination.

  As the substrate used for the circuit substrate, a glass epoxy substrate, a metal substrate, a polyester substrate, a polyimide substrate, a BT resin substrate, a thermosetting polyphenylene ether substrate, or the like can be used. In the present invention, the circuit board refers to a circuit board formed with a patterned conductor layer (circuit) on one or both sides of the board. A circuit board according to the present invention includes a circuit in which one side or both sides of the outermost layer of the multilayer printed wiring board is a circuit. The surface of the conductor layer may be previously roughened by blackening or the like.

The laminating conditions are preferably a pressure bonding temperature (laminating temperature) of 70 to 140 ° C. and a pressure bonding pressure of preferably 1 to 11 kgf / cm ² (9.8 × 10 ^{4 to} 107.9 × 10 ⁴ N / m ² ). Lamination is preferably performed under a reduced pressure of 20 mmHg (26.7 hPa) or less.

  The vacuum lamination can be performed using a commercially available vacuum laminator. Commercially available vacuum laminators include, for example, a vacuum applicator manufactured by Nichigo Morton Co., Ltd., a vacuum pressurizing laminator manufactured by Meiki Seisakusho Co., Ltd., a roll dry coater manufactured by Hitachi Industries, Ltd., and Hitachi AIC Co., Ltd. ) Made vacuum laminator and the like.

  After laminating the adhesive film on the circuit board in this way, the support film is peeled off. For example, when a release film is used, the support film may be peeled after curing. An insulating layer can be formed on the circuit board by thermosetting. The conditions for thermosetting are selected in the range of 20 to 180 minutes at 150 to 220 ° C, more preferably 30 to 120 minutes at 160 to 200 ° C.

  If the support film is not peeled off after the insulating layer is formed, it is peeled off here. If necessary, a via hole and a through hole are formed by drilling an insulating layer formed on the circuit board. Drilling can be performed by a known method such as drilling, laser, or plasma, or a combination of these methods if necessary. However, drilling by a laser such as a carbon dioxide laser or YAG laser is the most common method. .

  Next, the surface of the insulating layer is roughened with an oxidizing agent. Roughening is preferably performed using an alkaline permanganate solution (for example, potassium permanganate, sodium hydroxide aqueous solution of sodium permanganate) as the oxidizing agent. Next, a conductor layer is formed on the surface of the resin composition layer on which uneven anchors are formed by the roughening treatment by a method combining electroless plating and electrolytic plating. Alternatively, a plating resist having a pattern opposite to that of the conductor layer can be formed, and the conductor layer can be formed only by electroless plating. In addition, after forming the conductor layer, the peel strength of the conductor layer can be further improved and stabilized by annealing at 150 to 200 ° C. for 20 to 90 minutes. As a subsequent pattern formation method, for example, a subtractive method or a semi-additive method known to those skilled in the art can be used.

  The roughness of the roughened surface obtained by roughening the surface of the insulating layer (surface roughness Ra value) is preferably 0.5 μm or less, more preferably 0.35 μm or less in forming fine wiring. preferable. In addition, the surface roughness Ra value in this invention is the value which calculated | required Ra (10-point average roughness) using the non-contact-type surface roughness meter (WYKO NT3300 by Beeco Instruments). The Ra value is an average value of the heights calculated over the entire measurement region. Specifically, the Ra value is an arithmetic average obtained by measuring the absolute value of the height changing in the measurement region from the surface as an average line. Yes, it can be expressed by the following formula (1). Here, M and N are the number of data in each direction of the array.

  The prepreg in the present invention can be produced by impregnating the resin composition in the present invention into a sheet-like reinforcing substrate made of fibers by a hot melt method or a solvent method and semi-curing by heating. That is, it can be set as the prepreg which will be in the state which the resin composition in this invention impregnated the sheet-like reinforcement base material which consists of fibers.

  As the sheet-like reinforcing substrate made of fibers, for example, those commonly used as prepreg fibers such as glass cloth and aramid fibers can be used.

  In the hot melt method, without dissolving the resin in an organic solvent, the resin is once coated on the resin and a coated paper having good releasability, and then laminated on a sheet-like reinforcing substrate or directly applied by a die coater. Thus, a prepreg is manufactured. Similarly to the adhesive film, the solvent method is a method in which a sheet-like reinforcing base material is immersed in a resin varnish in which a resin is dissolved in an organic solvent, the resin varnish is impregnated into the sheet-like reinforcing base material, and then dried.

Next, the manufacturing method of the multilayer printed wiring board of this invention using a prepreg is demonstrated. One or several prepregs of the present invention are stacked on a circuit board, a metal plate is sandwiched through a release film, and press lamination is performed under pressure and heating conditions. The pressure is preferably 5 to 40 kgf / cm ² (49 × 10 ^{4 to} 392 × 10 ⁴ N / m ² ), and the temperature is preferably 120 to 200 ° C. for 20 to 100 minutes. Moreover, it can also be manufactured by laminating on a circuit board by a vacuum laminating method as in the case of an adhesive film, and then curing by heating. After that, after the surface of the cured prepreg is roughened as in the method described above, a multilayer printed wiring board can be manufactured by forming a conductor layer by plating.

  The present invention will be described in more detail with reference to the following examples and comparative examples, but these are not intended to limit the present invention in any way.

  Bisphenol F type epoxy resin (Japan Epoxy Resin Co., Ltd. “Epicoat 807”, epoxy equivalent of about 170) 15 parts by mass, triazine ring-containing phenol novolac resin (Dainippon Ink Co., Ltd. (Phenolite “EXB9889”), Phenol equivalent of about 120) 8 parts by mass, polyethersulfone resin ("PES5003P" manufactured by Sumitomo Chemical Co., Ltd.) 50% by mass of N, N-dimethylacetamide solution having a nonvolatile content of 20% by mass, bismaleimide compound and diamine compound 20 parts by mass of polymer ("E2020" manufactured by Printec Co., Ltd.), 0.16 parts by mass of a radical polymerization initiator ("PARK Mill D" manufactured by NOF Corporation), 8 parts by mass of N, N-dimethylacetamide , 20 parts by mass of spherical silica (“SOC2” manufactured by Admatechs Co., Ltd., average particle size of 0.5 μm) at room temperature The thermosetting resin composition varnish was prepared by dissolving and uniformly dispersing with a high-speed rotary mixer.Next, the resin varnish was formed on polyethylene terephthalate (thickness 38 μm, hereinafter abbreviated as PET), The resin thickness after drying was uniformly applied with a die coater so as to be 40 μm, and dried at 80 to 120 ° C. (average 100 ° C.) for 6 minutes (residual solvent amount of about 4% by mass). A polypropylene film having a thickness of 15 μm was attached to the film and wound into a roll shape, and the roll-shaped adhesive film was slit to a width of 507 mm, thereby obtaining a sheet-like adhesive film having a size of 507 × 336 mm.

  50 parts by mass of an N, N-dimethylacetamide solution having a nonvolatile content of 20% by mass of the polyethersulfone resin of Example 1 (“PES5003P” manufactured by Sumitomo Chemical Co., Ltd.) was changed to 35 parts by mass to obtain a polyamideimide resin (Toyo An adhesive film was obtained in exactly the same manner except that 26 parts by mass of “HR-16NN” manufactured by Spinning Co., Ltd. and an N-methylpyrrolidone solution having a nonvolatile content of about 14% by mass were added.

<Comparative Example 1>
20 parts by mass of a polymer of a bismaleimide compound and a diamine compound ("E2020" manufactured by Printec Co., Ltd.) in Example 1 was added to bis (3-ethyl-5-methyl-4-maleimidophenyl) methane (Kay Eye Chemicals). Co., Ltd. “BMI-70”) An adhesive film was obtained in exactly the same manner as in Example 1 except that the content was changed to 20 parts by mass.

<Evaluation of Tg (glass transition temperature) and thermal expansion coefficient by TMA method>
From the adhesive films obtained in Examples and Comparative Examples, the polypropylene film was peeled off and laminated on copper foil (manufactured by Nikko Materials Co., Ltd., “JTC-LP foil”) using a vacuum laminator. Subsequently, PET was peeled off and heated at 190 ° C. for 90 minutes to obtain a cured product of the resin composition with copper foil. Thereafter, the copper foil was removed with ferric chloride (manufactured by Tsurumi Soda Co., Ltd.), washed with water and dried at 130 ° C. for 15 minutes to obtain a cured product of the resin composition. The obtained cured product was cut into test pieces having a width of about 5 mm and a length of about 15 mm, and thermomechanical analysis was performed by a tensile load method using a thermomechanical analyzer manufactured by Rigaku Corporation (Thermo Plus TMA8310). After mounting the test piece on the apparatus, the test piece was measured twice continuously under the measurement conditions of a load of 1 g and a heating rate of 5 ° C./min. The average coefficient of linear expansion from 25 ° C. to 150 ° C. in the second measurement was calculated and used as the value of the thermal expansion coefficient. In addition, the second value of Tg was used.

<Measurement of strength at break and elongation at break>
From the adhesive films obtained in Examples and Comparative Examples, the polypropylene film was peeled off and laminated on copper foil (manufactured by Nikko Materials Co., Ltd., “JTC-LP foil”) using a vacuum laminator. Subsequently, PET was peeled off and heated at 190 ° C. for 90 minutes to obtain a cured product of the resin composition with a copper foil. Thereafter, the copper foil was removed with ferric chloride (manufactured by Tsurumi Soda Co., Ltd.), washed with water and dried at 130 ° C. for 15 minutes to obtain a cured product of the resin composition. In accordance with JIS K7172, dumbbell-shaped test pieces were cut out and a tensile test was performed using these test pieces. From the results, the strength at break and elongation at break of the cured product were calculated.

<Evaluation of laminating properties>
A double-sided wiring board having a conductor thickness of 35 μm and a L / S = 160 μm / 160 μm comb-tooth wiring formed on a glass epoxy board with a thickness of 0.4 mm is prepared. The roughening process was performed using "CZ8100" manufactured by Co., Ltd. The adhesive films produced in Examples and Comparative Examples on the substrate were vacuum pressure type laminator manufactured by Meiki Seisakusho Co., Ltd., MLP-500, with a degree of vacuum of 0.75 mmHg, a pressure bonding temperature of 130 ° C., and a pressure bonding pressure. The resin composition layer was laminated by pressing for 30 seconds under the condition of 58.8 × 10 ⁴ N / m ² . After the lamination, the PET was peeled off and thermally cured at 190 ° C. for 60 minutes to form an insulating layer. The comb-tooth wiring portion of the printed wiring board on which the insulating layer was formed was cut. Using a Keyence microscope, VK8510, cross-sectional observation was performed to determine the unevenness of the insulating layer. As shown in FIG. 1, the unevenness difference was obtained from the difference between the resin thickness (a) on the copper wiring and the resin thickness (b) at the portion without the copper wiring, and was evaluated based on the value having the largest unevenness.

<Peel strength evaluation>
(1) Substrate treatment of laminated board Glass cloth base epoxy resin double-sided copper-clad laminate [copper foil thickness 18 μm, substrate thickness 0.8 mm, Matsushita Electric Works R5715ES] A roughening treatment was performed using “CZ8100”.
(2) Lamination of adhesive film The adhesive film created in Examples and Comparative Examples was laminated on both surfaces of a laminate using a batch type vacuum pressure laminator MVLP-500 (manufactured by Meiki Co., Ltd.). Lamination was performed by reducing the pressure for 30 seconds to a pressure of 13 hPa or less, and then pressing at a pressure of 0.74 MPa for 30 seconds.
(3) Curing of resin composition The PET film was peeled from the laminated adhesive film, and the resin composition was cured under curing conditions at 170 ° C for 30 minutes.
(4) Roughening treatment The laminate is immersed in a swelling liquid, Swelling Dip Securigant P of Atotech Japan Co., Ltd. for 10 minutes at 80 ° C., and then the outlet of Atotech Japan Co., Ltd. as a roughening liquid. Immerse in rate compact P (KMnO ₄ : 60 g / L, NaOH: 40 g / L aqueous solution) at 80 ° C. for 20 minutes, and finally use Atotech Japan Co., Ltd. It was immersed for 5 minutes at 40 ° C.
(5) Plating by semi-additive method The laminate was immersed in an electroless plating solution containing PdCl ₂ and then immersed in an electroless copper plating solution. After annealing at 150 ° C. for 30 minutes, copper sulfate electroplating was performed to form a copper layer with a thickness of 25 ± 10 μm. Next, annealing treatment was performed at 180 ° C. for 30 minutes. The peel strength of the plated copper was measured for this laminate.
(6) Peeling strength (peel strength) test of plated copper layer Cut the 10mm width and 100mm length into the copper layer of the laminate, peel off the 10mm side and grab it with a gripper at room temperature The load when peeling 35 mm in the vertical direction at a speed of 50 mm / min was measured.

  The results of each test are shown in Table 1 for the samples of Examples and Comparative Examples. It can be seen that the example samples were formed with a plated copper layer having excellent heat resistance, mechanical strength, coefficient of thermal expansion, laminating properties, and excellent adhesion strength. In the table, “swelling” means that swelling occurred in the plating formation stage, and no conductor layer capable of measuring peel strength was formed.

  The production method of the present invention is suitable for producing a multilayer printed wiring board having an insulating layer having excellent heat resistance and mechanical strength and having a low coefficient of thermal expansion. Moreover, since the sheet-like laminated material used in the method of the present invention is excellent in laminating properties, a multilayer printed wiring board can be efficiently produced.

It is a conceptual diagram which shows the uneven | corrugated difference of the insulating layer formed on the circuit board.

Claims (8)

A method for producing a multilayer printed wiring board comprising a step of forming an insulating layer on a circuit board and a step of forming a conductor layer on the insulating layer, wherein the insulating layer comprises (A) a bismaleimide compound and a diamine compound. A resin composition containing a polymer, (B) an epoxy resin having two or more epoxy groups in one molecule, (C) a curing agent, (D) a polyethersulfone resin, and (E) an inorganic filler. It is formed by laminating on the circuit board in the form of a laminated material and then thermosetting, and the conductor layer is formed by plating on the roughened surface obtained by roughening the surface of the insulating layer with an oxidizing agent. A method for producing a multilayer printed wiring board, which is characterized. Sheet-like laminated material is an adhesive film in which a resin composition is layered on a support film, an adhesive film with a copper foil in which a resin composition is layered on a copper foil, or a sheet in which a resin composition is made of fibers The method according to claim 1, wherein the prepreg is impregnated in a reinforcing substrate. The sheet-like laminated material is an adhesive film in which the resin composition is layered on the support film, and the insulating layer heats the resin composition by peeling the support film after laminating the adhesive film on the circuit board. The method according to claim 1, wherein the method is formed by curing or peeling the support film after curing the resin composition. When the nonvolatile content of the resin composition is 100% by mass, the content of the component (A) is 10 to 50% by mass, the content of the component (B) is 15 to 45% by mass, and the content of the component (C) is The method according to any one of claims 1 to 3, wherein 3 to 20% by mass, the content of the component (D) is 10 to 50% by mass, and the content of the component (E) is 10 to 50% by mass. . The resin composition further comprises (F) one or more resins selected from the group consisting of polyimide resin, polyamideimide resin, polyamide resin, polyetherimide resin, polybenzoxazole resin, and polybenzimidazole resin. The method of any one of 1-4. The method of Claim 5 whose content of a component (F) is 1 to 10% when the non volatile matter of a resin composition is 100 mass%. The method according to claim 5 or 6, wherein the resin of component (F) is a polyamideimide resin. The method according to claim 1, wherein the oxidizing agent is an alkaline permanganate solution.

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