JP2008021700A - Method of manufacturing printed wiring board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a printed wiring board that is applicable to the manufacture of a micro circuit, and by which a conductive layer can be surely formed in holes when manufacturing multilayer wiring boards having holes such as a via hole or the like, and a printed wiring board can be manufactured in a short step and inexpensively. <P>SOLUTION: The method of manufacturing a printed wiring board includes at least a resist formation step wherein a hole 6 is made in an insulating substrate 1, a first metallic conductive layer 2 is formed, a material for forming a resist layer is discharged onto the surface of the first metallic conductive layer 2 by an electrostatic ink jetting, and a resist layer 3 for pattern electric plating is formed by curing; an electric plating step wherein a lamination on which the resist layer 3 for pattern electric plating is subject to electric plating, and a second metallic conductive layer 4 is formed like a pattern; a resist removing step to remove the resist layer 3 for electric plating; and an etching step wherein the first metallic conductive layer 1 is etched and removed in an area other than the formed second metallic conductive layer 4. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a printed wiring board, and more specifically, a circuit such as a printed wiring board and a semiconductor device capable of forming a patterned conductive layer having a high-definition and sufficient thickness by applying a semi-additive method. The present invention relates to a method for manufacturing a substrate.

  As a method for manufacturing a circuit board, a subtractive method, an additive method, and a semi-additive method are known. In the case of forming a fine circuit by the subtractive method, it is disadvantageous to the fine circuit because there is a thinning of an image line due to side etching of the metal conductive layer. On the other hand, the additive method is advantageous for a fine circuit, but has a problem of high manufacturing cost because all metal conductive layers are formed by electroless plating. The semi-additive method is multi-step, but can be used as a fine circuit manufacturing method because it can use electrolytic plating capable of high-speed operation.

  An example of a process for manufacturing a circuit board by the semi-additive method will be given. First, a thin first metal conductive layer 2 is provided on an insulating substrate 1 (FIG. 1A) (FIG. 1B). Next, a plating resist layer 3 is formed in the circuit non-formed part (FIG. 1C). Subsequently, the second metal conductive layer 4 is formed on the surface of the portion where the first metal conductive layer 1 is exposed by electrolytic plating (FIG. 1D). Thereafter, the resist layer 3 is removed (FIG. 1E), and the thin first metal conductive layer 1 under the resist layer is removed by etching to form a pattern comprising a first metal conductive layer and a second metal conductive layer. A substrate on which the circuit 5 is formed is obtained (FIG. 1F).

For forming the plating resist layer, a screen printing method, a photofabrication method having an exposure and development process using a photosensitive material, an ink jet method, an electrodeposition photoresist method, or the like is used. Among these, the screen printing method can be manufactured at a low cost, but cannot be used for high density and its application is limited. In order to cope with the higher density, the photofabrication method can be used advantageously. As a photofabrication method, a method using a negative type (photocrosslinking type) or a positive type (photolytic type) photoresist is generally used. However, the photofabrication method has a drawback in that it requires at least a process of applying a photosensitive material to a substrate, an exposure process, and a development process, and thus has many steps.
Although the inkjet method has a simple process, thermal and piezo inkjet recording methods are generally applied due to the characteristics of the resist material to be ejected. Although a high-density pattern can be formed, there is no practical example because the pattern resolution is inferior to that of the photofabrication method.

  By the way, with recent miniaturization and multi-functionalization of electronic devices, circuit boards are also being densified and wiring patterns are being miniaturized. As a means for achieving such conditions, multilayer circuit boards are being used. Can be mentioned. That is, a circuit board formed by laminating a plurality of wiring layers forms holes generally called through holes 21, via holes 22, and interstitial via holes 23 having the shape shown in FIG. As shown in (B), conduction between layers is performed through pores such as through-holes and non-through-holes whose inner walls are covered or filled with a metal conductive layer (hereinafter, these are collectively referred to as “holes”).

  FIG. 3 is a schematic view of the hole as viewed from above. A metal conductive layer called a land 32 is formed around the hole 31. There are various types of lands, such as a square, a circle, an ellipse, and an irregular shape. A circle is often used because of the occupied area or the ease of use of the design surface. In order to cope with higher density, a landless or narrow land-width hole is required.

  Next, an example of a process for manufacturing a circuit board having holes by the semi-additive method will be described. First, an insulating base substrate 1 (FIG. 4A) is prepared, and a hole 6 is formed therein (FIG. 4B). Thereafter, a thin first metal conductive layer is formed on the insulating substrate 1 having the hole 6. 2 is provided (FIG. 4C). Next, the plating resist layer 3 is formed in the circuit non-formed part (FIG. 4D). Subsequently, the second metal conductive layer 4 is formed on the surface of the portion where the first metal conductive layer 1 is exposed by electrolytic plating (FIG. 4F). Thereafter, the resist layer 3 is removed (FIG. 4F), and the thin first metal conductive layer 1 under the resist layer 3 is removed by etching to form a pattern comprising a first metal conductive layer and a second metal conductive layer. A substrate on which the circuit 5 is formed is obtained (FIG. 4G). In the semi-additive method, since the second metal conductive layer 5 is also provided inside the hole 6 by electrolytic plating, it is necessary that the plating resist layer is not formed in the hole 6 portion.

In order to prevent the plating resist from being formed in the hole portion in this way, when using the negative (photocrosslinking type) dry film photoresist described above, the hole and land portion are shielded from light, and the negative type is used. It is necessary to prevent the (photocrosslinking type) dry film photoresist from being crosslinked and to remove the unreacted dry film photoresist so as not to form a plating resist layer in the hole portion and the land portion. In this process, hole drilling and alignment of the exposure process are important. Especially in the case of landless and narrow land width holes required for high-density circuit boards, very high alignment accuracy is required. In the case of the land width, if the hole and the land are displaced at the same distance, there is a problem that a hole having a narrow land cannot be formed over the entire outer periphery.
Also, when manufacturing a landless hole, in the case of a hole with a small hole diameter, if the light shielding part is displaced, the light shielding part is detached from the hole, so that a negative (photocrosslinking type) dry film photoresist of the hole part is formed. There is a problem that the plating resist layer in the hole portion is not removed because of crosslinking (for example, see Patent Document 1).

  Actually, the alignment accuracy is limited due to the accuracy of drilling, expansion / contraction of the substrate, dimensional change of the photomask for exposure, and the like. Further, since the diameters of the holes formed on the high-density circuit board are various and the number of holes is extremely large, it is very difficult to accurately align all the holes. Therefore, in the case of a hole with a narrow land width, a negative type (photocrosslinking type) is ensured in the case of a hole with a narrow land width, even though a landless or narrow land width hole is required in a high-density circuit board. ) In order to prevent the dry film photoresist from cross-linking, there is a problem that the land width must be designed to be large (see, for example, Patent Document 2). In the case of a landless hole, the light shielding part must be designed to be small in order to ensure light shielding in the hole part and not to bridge the negative (photocrosslinking type) dry film photoresist. Therefore, it is difficult for the plating solution to enter the hole, and there is a problem that the plating is not performed.

As a method for forming a plating resist layer, Patent Document 2 also describes a method using an electrodeposition photoresist. This is a method of providing a plating resist layer by uniformly providing an electrodeposited photoresist layer on a metal conductive layer including the inner wall of the hole by an electrodeposition coating method, and then exposing and developing through a photomask. It is.
Electrodeposited photoresists include negative (photocrosslinking) and positive (photolytic). In the case of the positive type (photodecomposition type), it is necessary to expose and decompose the photoresist, but the cylindrical through-hole cannot expose the inside of the hole, and the electrodeposited photoresist inside can be completely decomposed. Since it cannot be used, it cannot be used as a plating resist layer. In a tapered via hole, a landless hole can be formed using a photomask having only a pattern having no land, but there is a problem that the electrodeposited photoresist inside the hole cannot be completely decomposed.

  In addition, when manufacturing a hole with a narrow land width, a photomask designed to expose the land portion is used, but as described in the above-mentioned negative (photocrosslinking type) dry film photoresist, Since there is a problem of alignment accuracy, there is a problem that the position of the land is shifted, and it is impossible to form a hole in which a narrow land exists over the entire outer periphery. Therefore, the land width must be increased, and there is a problem that the land cannot be narrowed.

  On the other hand, in the case of a negative type (photo-crosslinking type) electrodeposited photoresist, it is not necessary to expose the inside of the hole, so it is effective as a means of forming a landless hole using a photomask having only a pattern without a land. However, the tapered via hole has a problem that the plating resist layer on the inner wall and bottom surface of the hole cannot be removed because light partially penetrates. Therefore, in the case of a circuit board in which through holes and via holes coexist, it is impossible to remove the plating resist layer of all the holes existing in the circuit board.

In addition, when manufacturing a hole with a narrow land width using a negative type (photocrosslinking type) electrodeposition photoresist, a photomask designed to expose the land portion is used. As in the case of the mold) dry film photoresist, there is a problem of alignment accuracy, so that there is a problem that the land position is shifted.
As described above, the current resist manufacturing method has a problem that it cannot cope with the narrowing of lands, and a resist manufacturing method and a circuit formation method using the resist that can take advantage of the semi-additive method have been desired. .
JP-A-10-178031 Japanese Patent Laid-Open No. 7-7265

  An object of the present invention made in consideration of the conventional problems is to provide a method for manufacturing a printed wiring board that can be used for manufacturing a fine circuit and that can be manufactured at a low cost with a short process. It is in. In particular, when manufacturing a multilayer wiring board having a hole such as a via hole, a printed wiring board that can reliably form a conductive layer in the hole portion without being affected by the shape of the hole or the alignment accuracy of the exposure process. It is to provide a manufacturing method.

As a result of intensive studies to solve the above problems, the present inventors have found that the above problems can be solved by applying an electrostatic ink jet recording method to the formation of a pattern electroplating resist. completed.
That is, the present invention is as follows.
<1> A resist for pattern electroplating, in which a resist layer forming material is discharged onto a surface of a first metal conductive layer of a laminate comprising a first metal conductive layer on an insulating substrate by an electrostatic ink jet and cured. A resist forming step for forming a layer, an electroplating step for forming a second metal conductive layer in a pattern by electroplating the laminate on which the resist layer for pattern electroplating is formed, and removing the resist layer for electroplating A method for producing a printed wiring board, comprising: a resist removing step for performing, and an etching step for etching and removing the first metal conductive layer in a region other than the formed portion of the second metal conductive layer formed thereafter.

<2> After forming through holes and / or non-through holes in an insulating substrate, a metal conductive layer forming step of providing a first metal conductive layer, and forming a resist layer on the surface of the first metal conductive layer by electrostatic inkjet Forming a resist layer for pattern electroplating by discharging and curing the material, and electroplating the laminate on which the resist layer for pattern electroplating is formed to form a second metal conductive layer in a pattern An electroplating step to form, a resist removal step to remove the resist layer for electroplating, and then an etching step to etch away the first metal conductive layer in a region other than the formed portion of the formed second metal conductive layer; A method for producing a printed wiring board having at least

  According to the method for producing a printed wiring board of the present invention, since the resist is formed by the electrostatic ink jet method using the semi-additive method, it is possible to cope with the production of a fine circuit, the process is short, and the cost is low. Can be manufactured. In particular, when a multilayer wiring board having holes such as via holes is manufactured, the conductive layer can be reliably formed in the hole portions without being affected by the shape of the holes and the alignment accuracy of the exposure process.

Hereinafter, the manufacturing method of the present invention will be described in detail in the order of steps with reference to the drawings.
Here, an example using an insulating substrate in which holes are formed will be described. However, when an insulating substrate having no holes is used, the same process can be performed except for the “hole formation” step.
4A to 4G are cross-sectional views showing a method for manufacturing a circuit board having holes as a form of the circuit board manufacturing method of the present invention in the order of steps. Here, a description will be given by taking a through hole as an example, but a circuit board can be manufactured by a method similar to that described below even for a non-through hole. Further, even a build-up substrate in which through holes and via holes coexist can be manufactured by the same method.

<Metal conductive layer forming step of forming a first metal conductive layer after forming through holes and / or non-through holes in an insulating substrate>
First, an insulating base substrate 1 (FIG. 4A) is prepared, and holes 6 are formed therein (FIG. 4B).
Typical examples of the insulating substrate used in the present invention include paper-based phenolic resin and glass-based epoxy resin substrates, polyimide films, and liquid crystal polymer films. Examples of these insulating substrates are described in “Printed Circuit Technology Handbook” (edited by Japan Printed Circuit Industry Association, published in 1987, published by Nikkan Kogyo Shimbun), and a desired insulating substrate can be used.
The method for forming the hole 6 (through hole in this embodiment) is not particularly limited, and for example, any of the methods described in the above “Printed Circuit Technology Handbook” can be applied.

Thereafter, the thin first metal conductive layer 2 is provided on the insulating substrate 1 in which the holes 6 are formed (FIG. 4C).
The method for providing the first metal conductive layer 2 on the insulating substrate 1 according to the present invention is not particularly limited. For example, an electroless plating catalyst or a precursor thereof is attached to the surface of the substrate, and a metal thin film is formed by an electroless plating method. A method of forming, a method of pasting an ultra-thin conductive layer such as a metal foil on an insulating substrate, a method of forming a thin film by etching the conductive layer of a laminated plate bonded with a metal conductive layer, and the like. Can also be applied.
Here, as the conductive metal used for forming the first metal conductive layer, copper or an alloy containing copper is generally used from the viewpoint of conductivity, but is not limited thereto. Gold, silver, chromium, lead Further, metals such as tin and zinc or alloys containing these metals can also be used.
The film thickness of the first metal conductive layer to be formed can be appropriately selected depending on the application, but is generally preferably about 0.1 to 20 μm.

<Resist forming step of forming a resist layer for pattern electroplating by discharging and curing a resist layer forming material to the surface of the first metal conductive layer by electrostatic inkjet>
Next, a plating resist layer 3 is formed in a region where a circuit is not formed (FIG. 4D). The plating resist layer 3 is formed by an electrostatic ink jet method described in detail below.

The plating resist layer contains a resin that is soluble in the plating resist layer removing solution and insoluble in the electrolytic plating solution.
In the present invention, an electrostatic ink jet recording apparatus is used to form the plating resist layer 3 in a desired region. As an electrostatic ink jet recording apparatus that can be used in the present invention, for example, an ink jet recording apparatus described in JP-A-10-230608 can be used. FIG. 5 is a conceptual diagram of an ink jet head of an electrostatic ink jet recording apparatus that can be used in the present invention.

The inkjet head 50 includes a head substrate 52, an ink guide 54, an insulating substrate 56, a control electrode 58, an electrode substrate 60, a DC bias voltage source 62, and a pulse voltage source 64.
The insulating substrate 56 is formed with a discharge port (through hole) 66 for discharging ink. A head substrate 52 is provided so as to extend in the arrangement direction of the ejection ports 66, and an ink guide 54 is disposed on the head substrate 52 at a position corresponding to the ejection ports. The ink guide 54 passes through the ejection port 66, and the tip end portion 54 a protrudes above the surface of the insulating substrate 56 on the side opposite to the head substrate 52 side.

The head substrate 52 and the insulating substrate 56 are arranged at a predetermined interval, and a flow path for the ink Q is formed between them.
The ink Q containing fine particles (coloring material particles) charged with the same polarity as the voltage applied to the control electrode 58 is moved in the ink flow path 68 from the right side to the left side in the drawing by an ink circulation mechanism (not shown). The ink is circulated and ink is supplied to each ejection port 66.

The control electrode 58 is provided in a ring shape on the surface of the surface of the insulating substrate 56 on the recording medium P side so as to surround the periphery of the ejection port 66. The control electrode 58 is connected to a pulse voltage source 64 that generates a pulse voltage in accordance with image data. The pulse voltage source 64 is grounded via a DC bias voltage source 62.
In such electrostatic ink jet recording, the recording medium P is preferably grounded in a state where it is charged to a high voltage opposite to the control electrode by a charging device using a scorotron charger or the like. The insulating layer 61 is held.

In such electrostatic ink jet recording, when no voltage is applied to the control electrode 58, the bias voltage by the counter electrode and the Coulomb attractive force between the colorant particles in the ink, the viscosity of the ink (dispersion medium), The surface tension, the repulsive force between the charged particles, the fluid pressure of the ink supply, and the like are coupled, and the ink is balanced in a meniscus shape that is slightly raised from the discharge port (nozzle) 66.
Further, due to the Coulomb attractive force or the like, the color material particles migrate and move to a meniscus shape, that is, the ink is concentrated.

When a voltage is applied to the control electrode 58 (ejection ON), a bias voltage and a drive voltage are superimposed, and as a result, the ink Q is attracted to the recording medium P (opposite electrode) side and is a so-called tailor having a substantially conical shape. A cone is formed.
When time elapses after the voltage application starts, the balance between the Coulomb attractive force acting on the colorant particles and the surface tension of the dispersion medium is lost, and a slender ink liquid column with a diameter of about several μm to several tens of μm is formed. Is done. When the time further elapses, as disclosed in US Pat. No. 4,314,263, etc., the leading end of the kite string is cut, and ink droplets are ejected toward the recording medium P and fly by suction.

  In an electrostatic ink jet, normally, a pulse voltage is modulated and applied to each control electrode 58 to turn on / off ejection, modulate and eject ink droplets, and turn on according to the recorded image. Demand ink droplets are ejected.

(Ink composition for plating resist layer formation)
Here, the details of the ink composition for forming the resist layer will be described.
As the ink composition for forming the plating resist layer, an ink composition in which a component containing a polymer, a dispersant, and a charge control agent is dispersed in a carrier liquid is preferably used.

The carrier liquid is preferably a dielectric liquid having a high electrical resistivity, particularly 10 ¹⁰ Ωcm or more. If a carrier liquid having a low electrical resistivity is used, electrical conduction is caused between adjacent control electrodes, which is not suitable for the present invention.
The relative dielectric constant of the carrier liquid (dielectric liquid) is preferably 5 or less, more preferably 4 or less, and still more preferably 3.5 or less. It is preferable to set the relative dielectric constant of the dispersion times in this range because an electric field effectively acts on the particles of the carrier liquid.

Preferred examples of such a carrier liquid include linear or branched aliphatic hydrocarbons, alicyclic hydrocarbons, or aromatic hydrocarbons, halogen substitution products of these hydrocarbons, silicone oils, and the like. .
Examples include hexane, heptane, octane. Isooctane, decane, isodecane, decalin, nonane, dodecane, isododecane, cyclohexane, cyclooctane, cyclodecane, toluene, xylene, mesitylene, Isopar C, Isopar E, Isopar G, Isopar H, Isopar L, Isopar M (Isopar: from Exxon) Trade name), Shellsol 70, Shellsol 71 (Shellsol: trade name of Shell Oil), Amsco OMS, Amsco 460 solvent (Amsco: trade name of Spirits), KF-96L (trade name of Shin-Etsu Silicone) Etc. can be used alone or in combination.
The content of the carrier liquid with respect to the entire ink composition is preferably 20 to 99% by mass. By setting the content of the carrier liquid to 20% by mass or more, the particles can be favorably dispersed in the carrier liquid, and by setting the content to 99% by mass or less, the content of the particles can be satisfied.

The carrier liquid is preferably a dielectric liquid having a high electrical resistivity, particularly 10 ¹⁰ Ωcm or more. If a carrier liquid having a low electrical resistivity is used, electrical conduction is caused between adjacent control electrodes, which is not suitable for the present invention.
The relative dielectric constant of the carrier liquid (dielectric liquid) is preferably 5 or less, more preferably 4 or less, and still more preferably 3.5 or less. It is preferable to set the relative dielectric constant of the dispersion times within this range because an electric field effectively acts on the colorant particles of the carrier liquid.

In the ink composition for forming a resist layer, a polymer, which is a material that is cured to form a resist, is contained in a fine particle state in a carrier liquid.
Examples of the polymer include rosins, rosin-modified phenol resins, alkyd resins, (meth) acrylic polymers, polyurethane, polyester, polyamide, polyethylene, polybutadiene, polystyrene, polyvinyl acetate, polyvinyl alcohol, acetal-modified products of polyvinyl alcohol, polycarbonate, and the like. Can be mentioned.
Among these, from the viewpoint of ease of particle formation, the weight average molecular weight is in the range of 2,000 to 1,000,000 and the polydispersity (weight average molecular weight / number average molecular weight) is 1.0 to 5 Polymers in the range of 0.0 are preferred. Furthermore, from the viewpoint of ease of fixing, a polymer having any one of a softening point, a glass transition point, and a melting point within a range of 40 ° C. to 120 ° C. is preferable.

  Here, what is particularly preferably used as the polymer contains at least one of the structural units represented by the following general formulas (1) to (4), and contains an acid group such as (meth) acrylic acid. A polymer copolymerized with at least one of the structural units.

In the above formula, R ¹¹ represents a hydrogen atom or a methyl group, and R ¹² represents a hydrocarbon group having 1 to 30 carbon atoms. X ¹¹ represents an oxygen atom or —N (R ¹³ ) —, wherein R ¹³ represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms. R ²¹ represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms. R ³¹ , R ³² and R ⁴¹ each represent a divalent hydrocarbon group having 1 to 20 carbon atoms. Note that the hydrocarbon group of R ¹² , R ²¹ , R ³¹ , R ³² , and R ⁴¹ may contain an ether bond, an amino group, a hydroxy group, or a halogen substituent.

The polymer containing the structural unit represented by the general formula (1) can be obtained by radical polymerization of a corresponding radical polymerizable monomer by a known method.
Examples of the radical polymerizable monomer used include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, and (meth) acrylic. Octyl acid, 2-ethylhexyl (meth) acrylate, dodecyl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, phenyl (meth) acrylate, benzyl (meth) acrylate,
(Meth) acrylic acid esters such as 2-hydroxyethyl (meth) acrylate, and N-methyl (meth) acrylamide, N-propyl (meth) acrylamide, N-phenyl (meth) acrylamide, N, N-dimethyl Examples include (meth) acrylamides such as (meth) acrylamide.

  The polymer containing the structural unit represented by the general formula (2) can be obtained by radical polymerization of a corresponding radical polymerizable monomer by a known method. Examples of the radical polymerizable monomer used include ethylene, propylene, butadiene, styrene, and 4-methylstyrene.

The polymer containing the structural unit represented by the general formula (3) can be obtained by dehydrating condensation of a corresponding dicarboxylic acid or acid anhydride and a diol by a known method.
Examples of the dicarboxylic acid and acid anhydride used include succinic acid anhydride, adipic acid, sebacic acid, isophthalic acid, terephthalic acid, 1,4-phenylenediacetic acid, and diglycolic acid. Examples of the diol used include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 1,10-decanediol, and 2-butene- Examples include 1,4-diol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, 1,4-benzenedimethanol, and diethylene glycol.

  The polymer containing the structural unit represented by the general formula (4) is prepared by dehydrating condensation of a carboxylic acid having a corresponding hydroxy group by a known method or a known cyclic ester of a carboxylic acid having a corresponding hydroxy group. It is obtained by ring-opening polymerization by a method. Examples of the carboxylic acid having a hydroxy group or a cyclic ester thereof include 6-hydroxyhexanoic acid, 11-hydroxyundecanoic acid, hydroxybenzoic acid, and ε-caprolactone.

  The polymer containing at least one of the structural units represented by the general formulas (1) to (4) contains at least one of the structural units represented by the general formulas (1) to (4), Those copolymerized with at least one of structural units containing an acid group such as (meth) acrylic acid are preferred. Moreover, these polymers may be used independently and may be used in combination of 2 or more type.

  The polymer content relative to the entire ink composition is preferably 0.1 to 40% by mass. When the content of the polymer is 0.1% by mass or more, the amount of the polymer is satisfied and sufficient fixability is obtained, and when it is 40% by mass or less, the particles can be favorably formed. .

  Further, although the particles as described above are dispersed (particulate) in the carrier liquid, it is more preferable to use a dispersant in order to control the particle diameter and to suppress the sedimentation of the particles in the composition. . Suitable dispersants include surfactants typified by sorbitan fatty acid esters such as sorbitan monooleate and polyethylene glycol fatty acid esters such as polyoxyethylene distearate. Further, for example, a copolymer of styrene and maleic acid, and an amine-modified product thereof, a copolymer of styrene and (meth) acrylic compound, a (meth) acrylic polymer, a copolymer of polyethylene and (meth) acrylic compound, rosin, BYK-160, 162, 164, 182 (polyurethane polymer manufactured by Big Chemie), EFKA-401, 402 (acrylic polymer manufactured by EFKA), Solsperse 17000, 24000 (polyester polymer manufactured by Geneca), and the like. From the viewpoint of long-term storage stability of the ink composition, the dispersant has a weight average molecular weight in the range of 1,000 to 1,000,000 and a polydispersity (weight average molecular weight / number average molecular weight). Polymers that are in the range of 1.0 to 7.0 are preferred. Furthermore, it is most preferable to use a graft polymer or a block polymer.

  The polymer that is particularly preferably used as the dispersant includes a polymer component composed of at least one of the structural units represented by the following general formulas (5) and (6), and a structural unit represented by the following general formula (7). A graft polymer containing at least a polymer component contained as a graft chain.

In the above formula, R ⁵¹ represents a hydrogen atom or a methyl group, and R ⁵² represents a hydrocarbon group having 1 to 10 carbon atoms. X ⁵¹ represents an oxygen atom or —N (R ⁵³ ) —, wherein R ⁵³ represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms. R ⁶¹ represents a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, a halogen atom, a hydroxyl group, or an alkoxy group having 1 to 20 carbon atoms. R ⁷¹ represents a hydrogen atom or a methyl group, and R ⁷² represents a hydrocarbon group having 4 to 30 carbon atoms. X ⁷¹ represents an oxygen atom or —N (R ⁷³ ) —, wherein R ⁷³ represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms. The hydrocarbon group of R ⁵² and R ⁷² may contain an ether bond, an amino group, a hydroxy group, or a halogen substituent.

  The graft polymer is obtained by polymerizing a radically polymerizable monomer corresponding to the general formula (7), preferably in the presence of a chain transfer agent, and introducing a polymerizable functional group into the terminal of the obtained polymer. It can be obtained by copolymerizing with a radically polymerizable monomer corresponding to (5) or (6).

  Examples of the radical polymerizable monomer corresponding to the general formula (5) include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, and (meth) acrylic acid. Hexyl (meth) acrylate cyclohexyl, phenyl (meth) acrylate, benzyl (meth) acrylate, (meth) acrylic acid esters of 2-hydroxyethyl (meth) acrylate, and N-methyl (meth) acrylamide And (meth) acrylamides such as N-propyl (meth) acrylamide, N-phenyl (meth) acrylamide, and N, N-dimethyl (meth) acrylamide.

  Examples of the radical polymerizable monomer corresponding to the general formula (6) include styrene, 4-methylstyrene, chlorostyrene, methoxystyrene, and the like.

  Furthermore, examples of the radical polymerizable monomer corresponding to the general formula (7) include hexyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, dodecyl (meth) acrylate, ( (Meth) stearyl acrylate, and the like. Specific examples of these graft polymers that can be suitably used as a dispersant in the present invention include polymers represented by the following structural formulas ([BZ-1] to [BZ-6]).

  Contains a polymer component containing at least one of the structural units represented by general formulas (5) and (6) and a polymerization component containing at least the structural unit represented by general formula (7) as a graft chain. The graft polymer to be processed may have only the structural unit represented by the general formula (5) and / or (6) and the general formula (7), or may contain other components. A preferred composition ratio between the polymer component containing the graft chain and the other polymer components is 10:90 to 90:10. Within this range, good particle formability is obtained, and a desired particle diameter is easily obtained, which is preferable. These polymers may be used alone as a dispersant, or may be used in combination of two or more.

  The content of the dispersant with respect to the entire ink composition is preferably 0.01 to 30% by mass. By setting the content of the dispersant in this range, good particle forming properties can be obtained, and a desired particle diameter can be obtained.

The polymer is preferably contained in the carrier liquid by being dispersed in the form of particles using a dispersant, and more preferably used in combination with a charge adjusting agent in order to control the charge amount of the particles.
Suitable charge control agents used here include metal salts of organic carboxylic acids such as zirconium naphthenate and zirconium octenoate, ammonium salts of organic carboxylic acids such as tetramethylammonium stearate, and dodecylbenzenesulfonic acid. Contains metal salt of organic sulfonic acid such as sodium salt, magnesium dioctylsulfosuccinate, ammonium salt of organic sulfonic acid such as tetrabutylammonium toluenesulfonate, and carboxylic acid group modified with amine of styrene and maleic anhydride copolymer Such as a polymer having a carboxylic acid group in its side chain, a polymer having a carboxylic acid anion group in its side chain, such as a copolymer of stearyl methacrylate and tetramethylammonium methacrylate, and a copolymer of styrene and vinylpyridine Etc. on the side chain Examples thereof include polymers having an elementary atom, polymers having an ammonium group in the side chain, such as a copolymer of butyl methacrylate and N- (2-methacryloyloxyethyl) -N, N, N-trimethylammonium tosylate salt. .

  The charge control agent is preferably a polymer compound rather than a low molecular weight compound, and in particular, a polymer containing a carboxylic acid group is preferable. In particular, a copolymer having at least one monomer that can be soluble in a non-aqueous solvent and maleic anhydride as a constituent unit, and a primary amino compound, or a primary amino compound and a secondary amino compound And a polymer having a hemi-maleic acid amide component and a maleimide component as repeating units are preferably exemplified as a charge control agent.

In a polymer used as a charge control agent, monomers capable of forming a polymer soluble in a non-aqueous solvent are polymerizable alkenes, cycloalkenes, styrenes, vinyl ethers, allyl ethers, carboxylic acids Vinyl esters or allyl esters, and esters of unsaturated carboxylic acids such as methacrylic acid and acrylic acid.
More specifically, the monomer may be an alkene (eg, propenylene, butene, vinylidene chloride, ω-phenyl-1-propene, allyl alcohol, hexene, which may have a substituent having 3 to 40 carbon atoms in total. Octene, 2-ethylhexene, decene, dodecene, tetradecene, hexadecene, octadecene, dococene, eicosene, 10-undecenoic acid hexyl, etc., and C5-C40 cycloalkenes (for example, cyclopentene, cyclohexene, bicyclo [2, 2,1] -heptene-2, 5-cyanobicyclo [2,2,1] -heptene-2, etc.), styrenes optionally having substituents having 8 to 40 carbon atoms (for example, styrene, 4 -Methylstyrene, 4-n octylstyrene, 4-hexyloxystyrene, etc.),

Aliphatic group-substituted vinyl ethers having 1 to 40 carbon atoms in total or allyl ethers [Alkyl group which may have a substituent as an aliphatic group (for example, methyl group, ethyl group, butyl group, hexyl group, octyl group) Decyl group, dodecyl group, hexadecyl group, octadecyl group, docosanyl group, chloroethyl group, 2-ethylhexyl group, 4-methoxybutyl group, etc.), an aralkyl group which may have a substituent (for example, benzyl group, phenethyl) Group), an optionally substituted cycloalkyl group (eg, cyclopentyl group, cyclohexyl group, etc.), or an optionally substituted alkenyl group (eg, 2-pentenyl group, 4-propyl-2). -Pentenyl group, oleyl group, linoleyl group, etc.)], aromatic group-substituted vinyl ether having 6 to 40 carbon atoms in total Alternatively, allyl ethers [aromatic groups such as phenyl group, 4-butoxyphenyl group, 4-octylphenyl group, etc.], vinyl of aliphatic carboxylic acid which may have a substituent having 2 to 40 carbon atoms in total Esters or allyl esters (eg, esters of acetic acid, valeric acid, caproic acid, capric acid, lauric acid, myristic acid, palmamic acid, stearic acid, oleic acid, sorbic acid, linoleic acid, etc.), having a total carbon number of 6 or more Aromatic carboxylic acid vinyl esters or allyl esters (for example, benzoic acid, 4-butylbenzoic acid, 2,4-butylbenzoic acid, esters of 4-hexyloxybenzoic acid, etc.), or acrylic acid, methacrylic acid, malein Aliphatic group optionally having a substituent having 1 to 32 carbon atoms of unsaturated carboxylic acid such as acid and crotonic acid Ester (such as methyl group, ethyl group, propyl group, hexyl group, decyl group, 2-hydroxyethyl group, N, N-dimethylaminoethyl group).

  About the copolymer which has these monomers and maleic anhydride as a structural unit, the specific example suitable for following (1)-(22) is shown with the structural unit which comprises the copolymer. However, it is not limited to the following examples.

  The copolymer containing maleic anhydride as described above can be produced according to a conventionally known method. For example, Oda Ryohei, “Modern Industrial Chemistry Vol. 16, Polymer Industrial Chemistry I”, page 281 (published by Asakura Shoten), J. Am. Brandrup et al., “Polymer Handbook 2nd, Edition, John Wiley & Sons, New York, Chapter 2” describes in detail.

Here, the polymer suitably used as the charge control agent is a reactant of the copolymer containing maleic anhydride and an amino compound as described above. As the amino compound, a primary amino compound represented by the following general formula (8), a primary amino compound represented by the following general formula (8), and a secondary amino compound represented by the following general formula (9) are used.
Formula (8) R ⁸¹ NH ₂
Formula (9) R ⁹¹ R ⁹² NH

In the general formulas (8) and (9), R ⁸¹ , R ⁹¹ and R ⁹² represent an aliphatic group, an alicyclic hydrocarbon group, an aromatic group or a heterocyclic group, and R ^{91 in the} general formula (9) And R ⁹² may be the same or different. Preferably, an alkyl group having a substituent having 1 to 32 carbon atoms (for example, methyl group, ethyl group, propyl group, butyl group, hexyl group, octyl group, decyl group, dodecyl group, tetradecyl group, hexadecyl group) Group, octadecyl group, docosanyl group, chloroethyl group, cyanoethyl group, 4-butoxypropyl group, 2-ethylhexyl group, N, N-butylaminopropyl group, etc.), and having a substituent having 3 to 32 carbon atoms Good alkenyl group (for example, allyl group, 2-pentenyl group, 4-propyl-2-pentenyl group, decenyl group, oleyl group, linoleyl group, etc.), aralkyl group optionally having a substituent having 7 to 36 carbon atoms (For example, benzyl group, phenethyl group, etc.), alicyclic hydrocarbon group (for example, cyclopentyl group) which may have a substituent having 5 to 32 carbon atoms A cyclohexyl group, a bicyclo [2,2,1] -heptyl group, a cyclohexenyl group, etc.), an aryl group optionally having a substituent having 6 to 38 carbon atoms (for example, a phenyl group, a tolyl group, a 4-butylphenyl group). , 4-decylphenyl group, 4-butoxyphenyl group, etc.) or a heterocyclic group having 5 or more atoms (for example, furyl group, thienyl group, etc.). In the general formula (9), R ⁹¹ and R ⁹² may be closed with a carbon atom or may contain a hetero atom in the ring (for example, a morpholyl group).

  Specific examples of preferred amino compounds include ethylamine, propylamine, butylamine, pentylamine, hexylamine, octylamine, decylamine, dodecylamine, tetradecylamine, hexadecylamine, stearylamine, docosanylamine, 2-ethylhexylamine, 3 , 3-dimethylpentylamine, allylamine, hexenylamine, dodecenylamine, tetradecenylamine, hexadecenylamine, octadecenylamine, 2-nonyl-2-butenylamine, allylamine, cyclohexylamine, benzylamine, 4-n-octyl And aniline.

  In addition, a polymer that is a reactant of a copolymer having a monomer and maleic anhydride as a structural unit and an amino compound, which is preferably used as a charge control agent, is a polymer compound such as a half-maleic amide component and maleimide. Contains ingredients. Such a polymer is converted into a half-maleic acid amide copolymer by a polymer reaction between a maleic anhydride component in a polymer compound and a primary amino compound, and further subjected to a dehydration ring-closing reaction to thereby form one half-maleic acid amide component. It can be easily produced by changing the part to a maleimide component.

That is, in an organic solvent that does not cause a reaction between maleic anhydride and an amino compound and can dissolve both at the following reaction temperature [for example, hydrocarbons (for example, decane, isopa-G, isopa-H, Cielsol 71, cyclohexane, benzene, toluene, xylene, etc.), ketones (eg, methyl ethyl ketone, methyl isobutyl ketone, etc.), ethers (eg, dioxane, tetrahydrofuran, anisole, etc.), halogenated hydrocarbons (chloroform, dichloroethylene, methyl chloroform, etc.) , Dimethylformamide, dimethyl sulfoxide, etc., used alone or in combination]], each compound is mixed.
This is reacted at a temperature of 60 to 200 ° C., preferably 100 to 180 ° C., for 1 to 80 hours, preferably 3 to 15 hours. In this reaction, when a catalytic amount of an organic base (for example, triethylamine, dimethylaniline, pyridine, morpholine, etc.) or an inorganic or organic acid (for example, sulfuric acid, methanesulfonic acid, benzenesulfonic acid, etc.) is used, the reaction is accelerated. The Or you may use together normal dehydrating agents (for example, phosphorus pentoxide, dicyclocarboxydiimide, etc.).

  As described above, the reactant obtained by this reaction is a polymer compound containing a half-maleic acid amide and a maleinamide in the polymer, but the content of the half-maleic acid amide and the maleinamide is included in the polymer. Is from 10:90 to 90:10, preferably from 30:70 to 70:30. Further, the monomer part and maleic anhydride part that can form a polymer that is soluble in a non-aqueous solvent, constituting the polymer, are in a mass ratio of 10:90 to 99.5: 0.5, preferably 70:30 to 30:70. The molecular weight of the polymer compound is 1,000 to 500,000, preferably 5,000 to 50,000.

  Here, the charge imparted to the particles by the charge control agent may be a positive charge or a negative charge. The amount of the charge adjusting agent with respect to the entire ink composition is preferably in the range of 0.0001 to 10% by mass. Within this range, the electrical conductivity of the ink composition can be easily adjusted within the range of 10 nS / m to 300 nS / m.

  The ink composition used in the ink jet recording method of the present invention includes not only components such as the carrier liquid, polymer, dispersant, and charge control agent as described above, but also a preservative and surface for preventing corruption. Various components such as a surfactant for controlling the tension may be contained depending on the purpose.

As an example, such an ink composition can be prepared by dispersing a polymer and a dispersant in a carrier liquid to form particles, and adding a charge control agent to the carrier liquid to generate charge. The ink composition for forming a resist layer obtained by the adjustment is discharged by the ink jet recording apparatus onto a substrate having the hole 6 and having the first metal conductive layer 1 formed thereon. The ejection conditions, for example, the ink ejection amount per dot when ejecting, are appropriately selected depending on the resolution of the target pattern.
The ink composition for forming a resist layer applied on the first metal conductive layer 1 is removed from the solvent and cured to form the resist layer 3. The ejected ink composition can be cured even at room temperature, but can be dried by a conventional method such as a heater, infrared exposure, or hot air blowing if desired.
It is preferable that the thickness after drying of the resist layer 3 formed here is about 1 to 100 μm.

<Electroplating Step of Forming Second Metal Conductive Layer in Pattern by Performing Electroplating on Laminate Forming Resist Layer for Pattern Electroplating>
After forming the plating resist layer 3 in this way, the second metal conductive layer 4 is formed on the surface of the portion where the first metal conductive layer 1 is exposed by electrolytic plating (FIG. 4E).
The second metal conductive layer can be formed by an electrolytic plating method for the first metal conductive layer.
A conventionally well-known method can be used for an electrolytic plating process. In addition, as a metal used for the electroplating of this process, copper, chromium, lead, nickel, gold, silver, tin, zinc, etc. are mentioned. From the viewpoint of conductivity, copper, gold, and silver are preferable. More preferred.
The metal used for the second metal conductive layer formed by the electroplating process may be the same as or different from the metal used for forming the first metal conductive layer. Are preferably the same.
The second metal conductive layer may only cover the first metal conductive layer in the hole or may fill the hole.
There is no restriction | limiting in particular in the film thickness of a 2nd metal conductive layer, It changes with uses, It can control by adjusting the metal density | concentration contained in a plating bath, or a current density. In addition, the film thickness in the case of using it for general electric wiring etc. is preferably 0.5 μm or more, and more preferably 3 μm or more from the viewpoint of conductivity.

<Resist removal process for removing resist layer for electroplating>
After forming the second metal conductive layer, the resist layer 3 is removed (FIG. 4F).
The plating resist layer removing liquid according to the present invention is a solution that dissolves the plating resist layer, and uses a liquid that matches the composition of the plating resist layer to be used.
When an alkali-soluble resin is used for the plating resist layer, an aqueous alkali solution is usefully used. For example, alkali metal silicate, alkali metal hydroxide, phosphoric acid and alkali metal carbonate, phosphoric acid and ammonium carbonate An aqueous solution of an inorganic basic compound such as a salt, an organic basic compound such as ethanolamines, ethylenediamine, propanediamine, triethylenetetramine, and morpholine can be used. These aqueous solutions need to be adjusted in concentration, temperature, spray pressure, etc. in order to control the solubility of the plating resist layer. After the treatment with the plating resist layer removing solution, it is preferable to stop the unnecessary progress of dissolution of the plating resist layer by acid treatment and water washing treatment.

<Etching Step for Etching and Removing First Metal Conductive Layer in Region Excluding Formed Section of Formed Second Metal Conductive Layer>
Next, the thin first metal conductive layer 1 remaining after the removal of the resist layer 3 is etched away to obtain a substrate on which a patterned circuit 5 composed of the first metal conductive layer and the second metal conductive layer is formed ( FIG. 4 (G)).
The etching solution used for etching the first metal conductive layer according to the present invention may be any solution that can dissolve and remove the first metal conductive layer. For example, common etching solutions such as alkaline ammonia, sulfuric acid-hydrogen peroxide, cupric chloride, persulfate, ferric chloride, and the like can be used. Moreover, as an apparatus and a method, apparatuses and methods, such as horizontal spray etching and immersion etching, can be used, for example. These details are described in “Printed Circuit Technology Handbook” (edited by Japan Printed Circuit Industry Association, published in 1987, published by Nikkan Kogyo Shimbun).
Note that the laminated substrate after the etching treatment is preferably washed with an alkaline aqueous solution or water in order to remove the etching solution.
The patterned metal conductive layer thus obtained has a sufficient thickness and is formed according to a high resolution pattern. The manufacturing method of the printed wiring board of the present invention is a simple method, and a high-definition conductive circuit is formed. Therefore, the application range is wide.

Hereinafter, the present invention will be described with reference to examples.
A surface including the inside of the through hole after a 0.15mmφ through hole is made in a glass substrate epoxy resin substrate (area 340mm x 510mm, substrate thickness 0.1mm), followed by desmear treatment, electroless plating treatment An electroless copper plating layer having a thickness of 0.5 μm was provided as a first metal conductive layer.
Next, the following materials were prepared for forming a plating resist layer.
-Ink composition for resist layer formation-
・ Polymer [AP-1] 20g
・ Dispersant [BZ-2] 7.5g
・ Charge modifier [CT-1] 0.6g
・ Carrier fluid Isopar G (manufactured by Exxon Corporation) 391 g
The polymer [AP-1], dispersant [BZ-2], and charge control agent [CT-1] used in the ink composition have the following structural formula.

The polymer [AP-1], the dispersant [BZ-2], and the charge control agent [CT-1] were synthesized as follows.
<Polymer [AP-1]>
It was obtained by subjecting methyl methacrylate, butyl methacrylate and methacrylic acid to a radical polymerization reaction using a known polymerization initiator. The weight average molecular weight was 15,000, and the polydispersity (weight average molecular weight / number average molecular weight) was 2.7. The glass transition point (mid point) was 51 ° C., and the softening point by the strain gauge method was 46 ° C.

<Dispersant [BZ-2]>
Stearyl methacrylate was radically polymerized in the presence of 2-mercaptoethanol, and further reacted with methacrylic anhydride to give a polymer of stearyl methacrylate having a methacryloyl group at the terminal (weight average molecular weight was 7,600). ) This polymer was radically polymerized with styrene to obtain BZ-2. The weight average molecular weight was 110,000.
<Charge control agent [CT-1]>
It was obtained by reacting 1-octadecene and maleic anhydride copolymer with 1-hexadecylamine. The weight average molecular weight was 17,000.

Using each of the above materials, an ink composition containing particles was obtained as follows.
First, 20 g of the polymer [AP-1] was put into a tabletop kneader PBV-0.1 manufactured by Irie Shokai Co., Ltd., and the heater temperature was set at 100 ° C. and heated for 2 hours. And then finely pulverized with a SK-M10 type sample mill manufactured by Kyoritsu Riko Co., Ltd. The finely pulverized product obtained was predispersed in a paint shaker manufactured by Toyo Seiki Seisakusho together with 7.5 g of the dispersant [BZ-2], 75 g of Isopar G, and glass beads having a diameter of about 3.0 mm. After removing the glass beads, together with zirconia ceramic beads having a diameter of about 0.6 mm, a Type KDL dynomill manufactured by Shinmaru Enterprises Co., Ltd. was used for 5 hours while maintaining the internal temperature at 25 ° C., and subsequently at 45 ° C. for 5 hours. Dispersion (particle formation) was performed at a rotational speed of 000 rpm. Zirconia ceramic beads were removed from the obtained dispersion, and 316 g of Isopar G and 0.6 g of a charge control agent [CT-1] were added to obtain an ink composition [EC-1].

The electrical conductivity of [EC-1] of the ink composition at 20 ° C. was determined in the same manner as described above by using an LCR meter (AG-4311 manufactured by Ando Electric Co., Ltd.) and a liquid electrode (Kawaguchi Electric Manufacturing Co., Ltd.). LP-05 type) was used and measured under the conditions of an applied voltage of 5 V and a frequency of 1 kHz. The electrical conductivity of the entire ink was 100 nS / m. Further, using a small high-speed cooling centrifuge (Tomy Seiko Co., Ltd. SRX-201), the ink composition was centrifuged at a rotational speed of 14500 rpm and a temperature of 20 ° C. for 30 minutes to precipitate particles. Thereafter, the electrical conductivity of the supernatant was measured in the same manner. As a result, the electrical conductivity of the supernatant was 30 nS / m.
That is, the electrical conductivity of the particles is 70 nS / m, and the ratio of the electrical conductivity of the particles to the electrical conductivity of the supernatant is 2.3. Further, the volume average diameter of the particles was measured by centrifugal sedimentation using an ultracentrifugal automatic particle size distribution analyzer CAPA-700 (manufactured by Horiba, Ltd.) in the same manner as described above. It was. Further, the viscosity of the ink composition was 1.2 mPa · s.

Using the ink composition [EC-1] and an ink jet recording apparatus comprising the ink jet head 50 shown in FIG. 5, the first ejection electrode (not shown) is in a ground state (OFF) as a switch, The second discharge electrode 58 is changed to two states of 0 V (OFF) and +600 V (ON), and the surface of the recording medium P is −1600 V. The liquid droplets were ejected by setting the distance between the tip portion 54a of the ink guide 54 and the glass base epoxy resin substrate P provided with the first conductive layer to 500 μm. Here, under the above conditions, ink droplets were ejected when both the first ejection electrode and the second ejection electrode 58 were ON.
The line width and interval of the plating resist layer were 50 μm, and the variation in width was 4 μm.

  After confirming that the first metal conductive layer inside the through hole is completely exposed, electrolytic copper plating is performed to form an electrolytic copper plating layer having a thickness of 12 μm on the first metal conductive layer. Formed as. Subsequently, the plating resist layer was eluted and removed using a 3 mass% sodium hydroxide solution (30 ° C., 35 seconds) having a pH of 13.

Further, it was treated with a sulfuric acid-hydrogen peroxide etching solution (30 ° C., spray pressure: 2.0 kg / cm ² ) to remove the exposed first metal conductive layer. When the obtained circuit board was observed with a microscope, a metal conductive layer was uniformly formed inside the through hole.
The number of steps required for forming the metal conductive layer was seven.

(Comparative Example 1)
A surface including the inside of the through hole after a 0.15mmφ through hole is made in a glass substrate epoxy resin substrate (area 340mm x 510mm, substrate thickness 0.1mm), followed by desmear treatment, electroless plating treatment An electroless copper plating layer having a thickness of 0.5 μm was provided as a first metal conductive layer.
Using a dry film laminator, a commercially available negative-type (photocrosslinkable) dry film photoresist is subjected to thermocompression bonding, and then a baking high-pressure mercury lamp light source device (Unirec URM300, USHIO) having a suction adhesion mechanism through a photomask. For 30 seconds. A photomask having a conductor width and interval of 60 μm and a land diameter of 0.3 mmφ was used in order to completely shield the through hole portion. Subsequently, the plating resist layer was formed in the circuit non-formation part by performing alkali elution with 1 mass% sodium carbonate aqueous solution (liquid temperature of 35 degreeC).

Next, electrolytic copper plating was performed to form a second metal conductive layer having a thickness of 12 μm on the surface of the portion where the first metal conductive layer was exposed. Next, the photoresist layer was removed by treatment with a 3 mass% sodium hydroxide solution at 40 ° C. Then, it processed with the sulfuric acid-hydrogen peroxide type etching liquid (30 degreeC, spray pressure: 2.0 kg / cm < ² >), the 1st metal conductive layer was etched, and the circuit board was obtained. When the obtained circuit board was observed with a microscope, disconnection or the like was not confirmed on the circuit board.
Nine processes were required for forming the metal conductive layer wiring using the photoresist method.

(Comparative Example 2)
A surface including the inside of the through hole after a 0.15mmφ through hole is made in a glass substrate epoxy resin substrate (area 340mm x 510mm, substrate thickness 0.1mm), followed by desmear treatment, electroless plating treatment An electroless copper plating layer having a thickness of 0.5 μm was provided as a first metal conductive layer.
Using a dry film laminator, a commercially available negative-type (photocrosslinkable) dry film photoresist is subjected to thermocompression bonding, and then a baking high-pressure mercury lamp light source device (Unirec URM300, USHIO) having a suction adhesion mechanism through a photomask. For 30 seconds. The photomask is designed so that the light shielding area of the through hole portion is designed to be 0.08 mmφ so that the pattern width of the circuit forming portion is 50 μm and the pattern width is connected to it so that only the central portion of the through hole portion is not exposed. used. Subsequently, the plating resist layer was formed in the circuit non-formation part by performing alkali elution with 1 mass% sodium carbonate aqueous solution (liquid temperature of 35 degreeC). When the plating resist layer was observed, a through-hole in which the opening area of the dry film photoresist in the hole portion was reduced due to misalignment in the exposure process was confirmed.

Next, electrolytic copper plating was performed to form a second metal conductive layer having a thickness of 12 μm on the surface of the portion where the first metal conductive layer was exposed. Next, the photoresist layer was removed by treatment with a 3 mass% sodium hydroxide solution at 40 ° C. Then, it processed with the sulfuric acid-hydrogen peroxide type etching liquid (30 degreeC, spray pressure: 2.0 kg / cm < ² >), the 1st metal conductive layer was etched, and the circuit board was obtained. When the obtained circuit board was observed with a microscope, there were a portion where the thickness of the metal conductive layer inside the hole was uneven and a portion where the metal conductive layer inside the hole was not present.
The number of processes required for forming the metal conductive layer wiring using the photoresist method was nine.

  By applying the manufacturing method of the present invention, it is possible to increase the density without causing defects in the through holes, and the process is short, so that a printed wiring board having high-definition wiring can be manufactured at low cost.

(A)-(F) It is a schematic sectional drawing which shows an example of the process which manufactures a circuit board by a semi-additive method. (A) is a schematic sectional drawing which shows the shape of a through hole, a via hole, and an interstitial via hole, (B) is a schematic sectional drawing which shows the state which coat | covered these opening part inner walls with the metal conductive layer. It is the schematic which shows the state in which the land (metal conductive layer) is formed in the periphery of the opening part of holes, such as a through hole. (A)-(G) It is a schematic sectional drawing which shows an example of the process which manufactures the circuit board which provided the hole in the insulating substrate by the semi-additive method. It is a conceptual diagram of the inkjet head of the electrostatic inkjet recording device which can be used for formation of an electroplating resist layer in this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Insulating board | substrate 2 1st metal conductive layer 3 Plating resist layer 4 2nd metal conductive layer 6 Through hole (through-hole)
21 Through hole (through hole)
22 Via hole (non-through hole)
23 Interstitial via hole 31 Hole 32 Land 50 (Inkjet) head 52 Head substrate 54 Ink guide 54a Ink guide tip 56 Insulating substrate 58 Control electrode 61 Insulating substrate 62 DC bias voltage source 64 Pulse voltage source 66 Discharge port 68 Ink flow path

Claims (2)

  A resist layer forming material is formed by discharging and curing a resist layer forming material on the surface of the first metal conductive layer of the laminate comprising the first metal conductive layer on an insulating substrate by electrostatic inkjet. Forming a resist, forming a second metal conductive layer in a pattern by electroplating the laminate on which the patterned electroplating resist layer is formed, and removing the resist removing the electroplating resist layer The manufacturing method of the printed wiring board which has a process and the etching process of etching away the 1st metal conductive layer in area | regions other than the formation part of the formed 2nd metal conductive layer at least.   After forming through holes and / or non-through holes in an insulating substrate, a metal conductive layer forming step of providing a first metal conductive layer, and a resist layer forming material by electrostatic inkjet on the surface of the first metal conductive layer A resist forming step of forming a resist layer for pattern electroplating by discharging and curing, and an electric for forming a second metal conductive layer in a pattern by electroplating the laminate on which the resist layer for pattern electroplating is formed Printed wiring having at least a plating process, a resist removing process for removing a resist layer for electroplating, and an etching process for etching and removing the first metal conductive layer in a region other than a portion where the formed second metal conductive layer is formed A manufacturing method of a board.

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