JP6648959B2 - Method for producing plated product with good patternability - Google Patents

Description

  The present invention relates to a method for manufacturing a plated product having good patternability, and more particularly, to a method for manufacturing a plated product having a patterned metal film having a desired line width.

A technique for patterning a metal film on a transparent conductive film or a printed wiring board used for a touch panel or the like is known.
In the application of the transparent conductive film, an ITO film is generally often used, but a method of patterning a metal film such as copper into a mesh shape as a film having a lower resistance value has been performed.

On the other hand, in printed wiring board applications, photolithography technology is used for copper-clad laminates in which copper foil and a base material are bonded, and a circuit pattern is formed by dissolving unnecessary portions of copper foil. Is usually done.
Specifically, as described in, for example, Patent Document 1 (Japanese Patent Application Laid-Open No. 09-130016), a photoresist (photosensitive resin) is provided on a copper foil, exposed using a mask, developed, and etched. A method of forming a circuit pattern through a method called resist stripping is known.

JP 09-130016 A

  In the method described in Patent Literature 1, a copper foil exists under a photoresist, and at the time of exposure, light such as ultraviolet rays irradiated is reflected by the copper foil, and the photoresist under a mask, which is a portion that does not originally need to be exposed, is exposed. Because a part is exposed (exposed), when using this method to form a metal film patterned in a mesh shape with fine lines as used in a transparent conductive film, an area exposed by reflection becomes Since it is relatively large with respect to the line width (thin line), a metal film patterned with a line width different from the line width set by the mask will be formed.

  For example, when a negative type photoresist is used as a photoresist, the width of the photoresist after development becomes larger than the mask pattern, and etching is performed in the state of the photoresist having become wider than the width of the mask pattern. When the resist is stripped, a metal film patterned with a line width larger than the line width set by the mask is obtained, and when a positive photoresist is used, the photoresist after development is removed. When the width of the photoresist becomes narrower than the mask pattern and the photoresist is thinner than the width of the mask pattern, etching and stripping of the resist result in a line width smaller than the line width set by the mask. Since a patterned metal film is obtained, as a result, it becomes difficult to form a patterned metal film close to a desired line width. There was a cormorant problem.

  Therefore, an object of the present invention is to provide a method capable of solving the above-mentioned problem, that is, a method of manufacturing a plated product having a patterned metal film close to a desired line width.

The present inventors have conducted intensive studies to solve the above problems, and as a result, applied a paint containing polymer fine particles and a binder on the substrate surface to form a plating underlayer, and formed a photoresist layer on the plating underlayer. Was formed, exposed using a mask, and developed, etched, and stripped of resist. As a result, the polymer fine particles in the plating underlayer had a low light reflectance, so that the amount of reflected light such as ultraviolet light irradiated during exposure was low. As a result, the width of the photoresist after development becomes equivalent to the desired line width, and thereafter, by performing an electroless plating process, a patterned metal film close to the desired line width is formed. The present invention was found to be formed, and the present invention was completed.

That is, the present invention
[1] A method for producing a plated product in which a patterned metal film is formed on the surface of a substrate, and 1) applying a paint containing fine conductive polymer particles and a binder on the surface of the substrate, and performing plating. Forming a stratum a1,
2) a step b1 of forming a photoresist layer on the plating base layer;
3) exposing the photoresist layer through a patterned mask;
4) Step d1 of removing the photoresist layer according to the pattern by development after the exposure, and 5) Step e1 of removing the plating underlayer exposed by the development by etching.
6) Step f1 of removing the photoresist layer remaining on the base material;
7) a step g1 of removing the conductive polymer fine particles contained in the plating underlayer exposed by the removal of the remaining photoresist layer to convert them into reducible polymer fine particles, and 8) the dedoping treatment Providing a metal plating film on the plated underlayer by electroless plating treatment g2
A manufacturing method comprising
[2] The method according to [1], wherein the photoresist layer is formed of a negative photosensitive resist or a positive photosensitive resist.
[3] The manufacturing method according to [1] or [2], wherein the etching is performed by dry etching or wet etching.
[4] The method according to any one of [1] to [3], wherein the thickness of the plating underlayer formed in the step a1 is 1 μm or less,
[5] A method for producing a plated product in which a patterned metal film is formed on the surface of a base material, the method comprising: 1) applying a paint containing fine particles of a reducing polymer and a binder on the surface of the base material and performing plating; Forming a stratum a2,
2) a step b2 of forming a photoresist layer on the plating base layer;
3) exposing the photoresist layer through a patterned mask;
4) Step d2 of removing the photoresist layer according to the pattern by development after the exposure, and 5) Step e2 of removing the plating underlayer exposed by the development by etching.
6) Step f2 of removing the photoresist layer remaining on the base material, and 7) Step g3 of providing a metal plating film by electroless plating on the plating underlayer exposed by removing the remaining photoresist layer.
A manufacturing method comprising
[6] The method according to [5], wherein the photoresist layer is formed of a negative photosensitive resist or a positive photosensitive resist.
[7] The manufacturing method according to [5] or [6], wherein the etching is performed by dry etching or wet etching.
[8] The method according to any one of [5] to [7], wherein the thickness of the plating underlayer formed in the step a2 is 1 μm or less,
About.

According to the present invention, it is possible to manufacture a plated product having a metal film in a pattern close to a desired line width.
In the manufacturing method of the present invention, a process chart in the case of using a negative photoresist as a photoresist is shown in FIG. 1A, and a process chart in the case of using a positive photoresist is shown in FIG.
In the case of FIG. 1A using a negative type photoresist, the plating base layer 2 is formed uniformly over the entire surface of the substrate 1 in the step a, and the negative type plating is formed on the plating base layer 2 in the step b. Is formed. In step c, the negative photoresist layer 3a is exposed through the negative mask 4a. In step d, the negative photoresist layer 3a is not exposed by development. The portions are removed to form a patterned negative photoresist layer 3a. In step e, the plating underlayer 2 exposed by the development is removed by etching. In step f, the negative photoresist on the plating underlayer 2 is removed. The photoresist layer 3a is removed, and in step g, a metal plating film is formed on the exposed patterned plating base layer 2 by electroless plating. That.
In the case of FIG. 1B using a positive type photoresist, the plating base layer 2 is uniformly formed over the entire surface of the substrate 1 in the step a, and the positive type plating layer is formed on the plating base layer 2 in the step b. Is formed. In step c, the positive photoresist layer 3b is exposed through a positive mask 4b. In step d, the exposed portion of the positive photoresist layer 3b is developed. Is removed to form a patterned positive type photoresist layer 3b. In a step e, the plating underlying layer 2 exposed by the development is removed by etching, and in a step f, the positive type photoresist on the plating underlying layer 2 is removed. The resist layer 3b is removed, and in step g, a metal plating film is formed on the exposed patterned plating base layer 2 by electroless plating.
This makes it possible to easily obtain a plated product having a patterned metal film close to a desired line width.
Further, the production method of the present invention can be performed by any of dry etching and wet etching as an etching method, and further, any of conductive fine particles and reducing fine particles can be used as polymer fine particles. Therefore, it can be said that the method is very versatile.

In a preferred embodiment of the present invention, a production method in which the thickness of the plating underlayer is 1 μm or less is exemplified.
By setting the thickness of the plating base layer to 1 μm or less, a metal film having a fine width is formed by wet etching (particularly, isotropic). Specifically, the desired line width is 3 μm or less. Even with a very fine width of 2 μm or less, a plated product having a patterned metal film close to the desired line width can be manufactured.
When wet etching, particularly isotropic wet etching, is employed as the etching method, as shown in FIG. 2, the etching solution 6 not only removes the plating underlayer 2 vertically from the edge of the resist layer 3 but also removes the plating underlayer 2. In addition, the etching solution 6 goes around the inside of the plating underlayer 2 under the resist layer 3 and also removes side portions of the plating underlayer 2 (side etching, over etching).
As a result, the width of the formed plating underlayer 2 becomes narrower than the width of the resist layer 3 after development, and as a result, a patterned metal plating film was formed on the plating underlayer by electroless plating. In this case, the line width of the formed patterned metal film is smaller than the line width of the desired patterned metal film.
The effects of the side etching and the over-etching as described above can be suppressed by making the plating underlayer sufficiently thin, and when the thickness of the plating underlayer is about 1/2 or less of the desired line width, In some cases, it is possible to manufacture a plated product having a patterned metal film close to a desired line width. Therefore, when manufacturing a plated product in which the line width of the patterned metal film is 3 μm or less and the finer width is 2 μm, if the thickness of the plating underlayer is 1 μm or less, for example, wet etching is used as an etching method. Even when (isotropic) is adopted, it is possible to manufacture a plated product on which a patterned metal plating film having a substantially desired line width is formed, thereby adopting isotropic wet etching. In this case, a fine pattern having a line width of 2 μm or less can be formed with a substantially desired line width.

FIG. 4 is a process chart showing the steps of the production method of the present invention. It is a figure explaining wet etching (isotropic). 4 is an electron micrograph of the surface of a plated product manufactured in Example 1 on which a metal plating film having a line width of 1.8 μm is formed.

The present invention will be described in more detail.
The method for producing a plated product in which a patterned metal film is formed on the substrate surface of the present invention,
1) a step a1 of applying a paint containing conductive polymer fine particles and a binder on the surface of a base material to form a plating underlayer;
2) a step b1 of forming a photoresist layer on the plating base layer;
3) exposing the photoresist layer through a patterned mask;
4) Step d1 of removing the photoresist layer according to the pattern by development after the exposure, and 5) Step e1 of removing the plating underlayer exposed by the development by etching.
6) Step f1 of removing the photoresist layer remaining on the base material;
7) a step g1 of removing the conductive polymer fine particles contained in the plating underlayer exposed by the removal of the remaining photoresist layer to convert them into reducible polymer fine particles, and 8) the dedoping treatment Providing a metal plating film on the plated underlayer by electroless plating treatment g2
It is characterized by consisting of.

Hereinafter, the steps a1 to g1 and g2 will be sequentially described.
(1) Step a1 Step a1 is a step of applying a paint containing conductive polymer fine particles and a binder on the surface of the base material to form a plating underlayer.
The substrate that can be used in the present invention is not particularly limited, for example, polyester resins such as polyethylene terephthalate, acrylic resins such as polymethyl methacrylate, polypropylene resins, polycarbonate resins, polystyrene resins, poly Examples thereof include vinyl chloride resin, polyamide resin, polyimide resin, glass, and metal.
Further, the shape of the substrate is not particularly limited, and examples thereof include a plate shape and a film shape. In addition, examples of the substrate include a resin molded product obtained by molding a resin by injection molding or the like. Then, by providing the plated product of the present invention on this resin molded product, for example, by providing the plated product of the present invention in a pattern on a film made of a polyimide resin or polyethylene terephthalate resin, for example, an electric circuit product is created. can do.
The thickness of the substrate is preferably in the range of 5 to 200 μm, more preferably 12 to 100 μm.

The paint contains conductive polymer fine particles and a binder.
The conductive polymer fine particles are particles having conductivity, specifically, particles having a conductivity of 0.01 S / cm or more.
Examples of the conductive polymer fine particles include spherical fine particles, and the average particle diameter (value obtained by a laser diffraction / scattering method) is preferably 10 to 100 nm.
The conductive polymer fine particles are not particularly limited as long as they are polymers having a conductive π-conjugated double bond.For example, polyacetylene, polyacene, polyparaphenylene, polyparaphenylene vinylene, polypyrrole, polyaniline, and polythiophene And various derivatives thereof, and preferably, polypyrrole, which is black and has low light reflectance.
The conductive polymer fine particles can be used by synthesizing from a monomer having a π-conjugated double bond, and commercially available conductive polymer fine particles can also be used.

The conductive polymer fine particles are usually used as a dispersion dispersed in an organic solvent, and these fine particles are used as a solid to maintain the dispersion stability in the dispersion. Is preferably 10% by mass or less (solid content ratio).
Examples of the organic solvent for dispersing the fine particles include aliphatic esters such as butyl acetate, aromatic solvents such as toluene, ketones such as methyl ethyl ketone, cyclic saturated hydrocarbons such as cyclohexane, and chains such as n-octane. Saturated hydrocarbons, chain saturated alcohols such as methanol, ethanol and n-octanol, aromatic esters such as methyl benzoate, aliphatic ethers such as diethyl ether, and mixtures thereof.

The binder contained in the paint is not particularly limited, for example, polyvinyl chloride resin, polycarbonate resin, polystyrene resin, polymethyl methacrylate resin, polyester resin, polysulfone resin, polyphenylene oxide resin Resin, polybutadiene resin, poly (N-vinylcarbazole) resin, hydrocarbon resin, ketone resin, phenoxy resin, polyamide resin, ethylcellulose resin, vinyl acetate resin, ABS resin, urethane resin, Melamine resins, acrylic resins, unsaturated polyester resins, alkyd resins, epoxy resins, silicone resins, and photosensitive resins for photoresists are exemplified.
Preferred binders include polyester resins and melamine resins.

  The solid content ratio (mass ratio) between the conductive polymer fine particles and the binder is preferably in the range of 1: 0.25 to 1:10. In the above-mentioned solid content ratio, when the solid content ratio of the binder is smaller than 1: 0.25, the adhesion of the metal plating film tends to be reduced and peeling tends to occur, and the solid content ratio of the binder is more than 1:10. When it becomes large, there is a tendency that plating deposition property is reduced and plating is difficult to deposit.

The coating material may include an inorganic filler, a solvent, and the like in addition to the components.
Examples of the inorganic filler include carbon particles, and examples of the carbon particles include carbon black.
As the carbon particles, those having an average primary particle diameter in the range of 1 to 100 nm are preferable.
From the viewpoint that the reflection of light such as ultraviolet rays can be further suppressed (blackening), it is preferable to add carbon particles to the paint.
When the inorganic filler is used, the solid content ratio (mass ratio) of the binder and the inorganic filler (carbon particles) is preferably in the range of 1: 1.5 to 1:30. In the above solid content ratio, when the solid content ratio of the carbon particles is smaller than 1: 1.5, it is difficult to suppress the light reflection of the metal plating film, and it is difficult to secure the visibility as a transparent conductive film such as a touch panel. When the solid content ratio of the carbon particles is larger than 1:30, the plating deposition property tends to decrease, and the plating tends to be difficult to deposit.

The solvent is not particularly limited, but specific examples thereof include aliphatic esters such as butyl acetate, aromatic solvents such as toluene, ketones such as methyl ethyl ketone, cyclohexanone and isophorone, and cyclic saturated carbon such as cyclohexane. Hydrogens, chain saturated hydrocarbons such as n-octane, chain saturated alcohols such as methanol, ethanol, and n-octanol; aromatic esters such as methyl benzoate; aliphatic ethers such as diethyl ether; And the like.
In addition, solvents classified as terpenes such as polyhydric alcohol derivative solvents such as methylcellosolve, hydrocarbon solvents such as mineral spirits, dihydroterpineol, and D-limonene can also be used.

The above-mentioned paint can also add a black ink or a dark color ink, and further, if necessary, such as an application or an object to be applied, a dispersion stabilizer, a thickener, and a resin such as an ink binder can be added. is there.
It is preferable that the above-mentioned paint contains the above-mentioned components so that the viscosity of the solution is 50 cps or more.
When the viscosity is less than 50 cps, a general-purpose printing machine, for example, a screen printing method, a screen offset method, a gravure printing method, a gravure offset printing method, a flexographic printing method, an imprint printing method, a reverse printing method, an inkjet printing method, and the like. This is because the printing accuracy of the print pattern may be reduced due to this.

As a method of forming the plating underlayer by applying the coating material on the surface of the substrate, there is a method of printing (overall printing) the coating material on the surface of the substrate.
In addition, when forming a plating underlayer on both surfaces of a base material, it can be achieved by repeating the above operation.
The printing using the paint (full-surface printing) is not particularly limited, and examples thereof include a screen printing method, a screen offset method, a gravure printing method, a gravure offset printing method, a flexographic printing method, an imprint printing method, and a reverse printing method. And an inkjet printing method. The printing method can be performed by a normal printing method using each printing machine.

The thickness of the plating underlayer to be formed is preferably in the range of 0.1 to 1.5 μm. When the thickness of the plating underlayer is less than 0.1 μm, the plating deposition property tends to decrease and the plating tends to be difficult to deposit, and when the thickness of the plating underlayer exceeds 1.5 μm, the fine wire pattern ( (Line width 3 μm or less) tends to be difficult to form.
Further, when wet etching (especially isotropic) is employed as the etching method and a patterned metal film having a fine width (for example, 2 μm or less) is formed, the thickness of the plating base layer is set to 1 μm or less. It is preferable to keep it.
When the line width of the metal film to be formed is a fine width and the etching method is wet etching, in particular, isotropic, the overetching inevitably occurring in the etching method is suppressed to a small value, and is close to a desired line width. In order to obtain a plated product having a patterned metal film, it is required that the thickness of the plating underlayer be thin, for example, １ ／ or less of the line width of the metal film to be formed.
When the thickness of the plating base layer is set to 1 μm or less, a metal film having a fine width is formed by wet etching (particularly, isotropic), and a desired line width is set to 3 μm or less. Even with a very fine width of 2 μm or less, it is possible to manufacture a plated product having a patterned metal film close to the desired line width.

(2) Step b1 Step b1 is a step of forming a photoresist layer on the plating underlayer formed in step a1.
The formation of the photoresist layer can be performed by a conventional method using a photosensitive resist.
The photosensitive resist is not particularly limited as long as it is a photosensitive resist that does not dissolve in the etching solution used in the step e1 described below, and is a solvent-developing type or an alkali-developing type, a sheet-like dry film, an ink, or the like. And the like, and any of a negative photosensitive resist and a positive photosensitive resist can be used, and photoresists for all exposure wavelengths can be used.
The above-mentioned photosensitive resist can be prepared and used in advance, but a commercially available resist can also be used.

  A photoresist layer is formed by affixing the above-mentioned sheet-shaped dry film on the plating underlayer formed in step a1 or applying the above-mentioned photosensitive resist ink on the plating underlayer formed in step a1. be able to.

(3) Step c1 Step c1 is a step of exposing the photoresist layer formed in step b1 through a patterned mask.
Specifically, it can be achieved by irradiating the photoresist layer with light such as ultraviolet rays through a mask pattern.
As the mask pattern, any of a negative type and a positive type can be applied.
As a light source of the ultraviolet light to be irradiated, a commonly used light source such as a high-pressure mercury lamp, a metal halide lamp, a halogen lamp, a xenon lamp, and a germicidal lamp can be used.

(4) Step d1 Step d1 is a step of removing the photoresist layer according to a pattern by development after the exposure in step c1.
Specifically, this is achieved by immersing the exposed material in step c1 in a developing solution corresponding to the photosensitive resist used in step b1, and removing the photosensitive resist other than the pattern portion.

(5) Step e1 Step e1 is a step of removing the plating underlayer exposed by the development in step d1 by etching.
The etching method is not particularly limited as long as the photoresist layer formed in step b1 is not removed and only the plating underlayer formed in step a1 can be removed, and either dry etching or wet etching is used. And either isotropic or anisotropic can be used.

Examples of wet etching include, for example, a method using a mineral acid such as an aqueous solution of nitric acid as an etchant, and examples of dry etching include reactive gas etching in which a material is exposed to a reactive gas, and ionization / radicalization of a gas by plasma. There is reactive ion etching for etching, etc., but reactive gas etching using xenon difluoride (X ₂ F ₂ ) as a reaction gas or sulfur hexafluoride (SF ₆ ) or carbon tetrafluoride (CF ₄ ) as a gas And reactive ion etching using trifluoromethane (CHF ₃ ).
It is preferable to use the RIE method which is dry etching, particularly anisotropic etching.

(6) Step f1 Step f1 is a step of removing the photoresist layer remaining on the base material.
Specifically, this is achieved by immersing the etched one in the step e1 in a rinse solution corresponding to the photosensitive resist used in the step b1, and removing the photosensitive resist remaining on the base material.

(7) Step g1 The step g1 is a step of dedoping the conductive polymer fine particles contained in the plating underlayer exposed by removing the remaining photoresist layer into the reducing polymer fine particles. is there.
As the undoping treatment, the substrate on which the patterned plating underlayer is formed is treated with a reducing agent,
For example, sodium borohydride, borohydride compounds such as potassium borohydride, dimethylamine borane, diethylamine borane, trimethylamine borane, alkylamine borane such as triethylamine borane, and a method of reducing by treating with a solution containing hydrazine and the like. Or a method of treating with an alkaline solution.

It is preferable to treat with an alkaline solution from the viewpoint of operability and economy.
In particular, since the plating underlayer containing the conductive polymer fine particles is very thin, undoping can be achieved by alkali treatment for a short time under mild conditions.
For example, the treatment is carried out in a 1 M aqueous sodium hydroxide solution at a temperature of 20 to 50 ° C., preferably 30 to 40 ° C., for 1 to 30 minutes, preferably 3 to 10 minutes.
By the above-described undoping treatment, the conductive polymer fine particles present in the plating underlayer become reducible polymer fine particles.

(8) Step g2 Step g2 is a step of providing a metal plating film on the undoped plating base layer by electroless plating.
The electroless plating can be performed according to a generally known method.
That is, after immersion of the substrate on which the pattern-shaped plating base layer was formed, which was subjected to the undoping treatment in step g2, was immersed in a catalyst solution for attaching a catalyst metal such as palladium chloride, washing with water, etc., was performed. A metal plating film can be provided by immersion in an electroless plating bath.
The catalyst solution is a solution containing a noble metal (catalyst metal) having catalytic activity for electroless plating. Examples of the catalyst metal include palladium, gold, platinum, and rhodium. These metals may be used alone or as a compound. A palladium compound is preferable from the viewpoint of stability including a metal, and among them, palladium chloride is particularly preferable.
Preferred and specific catalyst liquids include 0.05% palladium chloride-0.005% hydrochloric acid aqueous solution (pH 3).
The processing temperature is 20 to 50 ° C., preferably 30 to 40 ° C., and the processing time is 0.1 to 20 minutes, preferably 1 to 10 minutes.
By the above operation, the fine particles made reducible by the de-doping treatment have the catalytic metal adsorbed on the fine particles, resulting in conductive polymer fine particles.

The substrate treated as described above is immersed in a plating solution for depositing a metal, whereby a patterned metal plating film is formed.
The plating solution is not particularly limited as long as it is a plating solution usually used for electroless plating.
That is, any of metals, copper, gold, silver, nickel, and the like that can be used for electroless plating can be applied, but copper is preferable.
Specific examples of the electroless copper plating bath include an ATS Adcopper IW bath (manufactured by Okuno Pharmaceutical Co., Ltd.).
The processing temperature is 20 to 50 ° C., preferably 30 to 40 ° C., and the processing time is 1 to 30 minutes, preferably 5 to 15 minutes.
It is preferable that the obtained plated product be cured for several hours or more, for example, two hours or more in a temperature range lower than the Tg of the used substrate.
The thickness of the formed patterned metal plating film is preferably in the range of 100 to 2000 nm, more preferably in the range of 200 to 500 nm.

If necessary, a metal plating film by an electrolytic plating method may be formed on a patterned metal plating film formed by an electroless plating method, or a blackening treatment may be performed.
The blackening treatment of the surface of the patterned metal plating film is performed, for example, by performing an oxidation treatment (for example, an oxidation treatment using an aqueous solution of sodium chlorite, sodium hydroxide, and trisodium phosphate) to form a CuO film, for example. This can be achieved by:

According to the above-described manufacturing method, a plated product in which a patterned metal film is formed on a substrate surface is manufactured.
The conductivity of the obtained plated product is usually 1.0 Ω / □ or less.
The width of the line formed in the metal plating film is preferably 10 μm or less from the viewpoint of visibility.
In addition, from the viewpoint of visibility, the obtained plated product preferably has an average light reflectance at 380 to 780 nm of 10% or less.

As a method of manufacturing a plated product having a patterned metal film formed on the substrate surface of the present invention,
1) a step a2 of applying a paint containing reducing polymer fine particles and a binder on the surface of a base material to form a plating underlayer;
2) a step b2 of forming a photoresist layer on the plating base layer;
3) exposing the photoresist layer through a patterned mask;
4) Step d2 of removing the photoresist layer according to the pattern by development after the exposure, and 5) Step e2 of removing the plating underlayer exposed by the development by etching.
6) a step f2 of removing a photoresist layer remaining on the base material, and 7) a step g3 of providing a metal plating film by electroless plating on the plating base layer exposed by removing the remaining photoresist layer.
And a method characterized by comprising:

Step a2 can be performed under exactly the same conditions except that the conductive polymer fine particles in the above-described step a1 are replaced with reducing polymer fine particles.
The reducing polymer fine particles are not particularly limited as long as they are polymers having a π-conjugated double bond having a conductivity of less than 0.01 S / cm. For example, polyacetylene, polyacene, polyparaphenylene, polyparaphenylene Examples thereof include vinylene, polypyrrole, polyaniline, polythiophene, and various derivatives thereof, and preferably, polypyrrole that is black and has low light reflectance.
Further, as the reducing polymer fine particles, polymer fine particles having a conductivity of 0.005 S / cm or less are preferable.
The reducing polymer particles can be used by synthesizing from a monomer having a π-conjugated double bond, and commercially available reducing polymer particles can also be used.
The reducing polymer fine particles are used as a dispersion dispersed in an organic solvent, and the reducing polymer fine particles are used as a solid component in order to maintain dispersion stability in the dispersion. Is preferably 10% by mass or less (solid content ratio).
Examples of the reducing polymer fine particles include spherical fine particles, and the average particle diameter (value obtained by a laser diffraction / scattering method) is preferably 10 to 100 nm.

Steps b2 to f2 can be performed under exactly the same conditions as steps b1 to f1 described above, respectively.
In addition, since this manufacturing method uses the reducing polymer fine particles, the step g1 described above, that is, the step of the undoping process of converting the conductive polymer fine particles into the reducing polymer fine particles is not required. .
The step g3 can be performed under exactly the same conditions as the step g2 described above.

If necessary, a metal plating film by an electrolytic plating method may be formed on a patterned metal plating film formed by an electroless plating method, or a blackening treatment may be performed.
The blackening treatment of the surface of the patterned metal plating film is performed, for example, by performing an oxidation treatment (for example, an oxidation treatment using an aqueous solution of sodium chlorite, sodium hydroxide, and trisodium phosphate) to form a CuO film, for example. This can be achieved by:

According to the above-described manufacturing method, a plated product in which a patterned metal film is formed on a substrate surface is manufactured.
The conductivity of the obtained plated product is usually 1.0 Ω / □ or less.
The width of the line formed in the metal plating film is preferably 10 μm or less from the viewpoint of visibility.
In addition, from the viewpoint of visibility, the obtained plated product preferably has an average light reflectance at 380 to 780 nm of 10% or less.

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the examples.
Production Example 1: Preparation of conductive polypyrrole paint 1.5 mmol of anionic surfactant Perex OT-P (manufactured by Kao Corporation), 10 mL of toluene, and 100 mL of ion-exchanged water were added, and the mixture was stirred at 20 ° C. until emulsified. did. To the obtained emulsion, 21.2 mmol of a pyrrole monomer was added, and the mixture was stirred for 1 hour. Then, 6 mmol of ammonium persulfate was added to carry out a polymerization reaction for 2 hours. After completion of the reaction, the organic phase was recovered and washed several times with ion-exchanged water to obtain conductive polypyrrole fine particles dispersed in toluene. The solid content of the conductive polypyrrole fine particles in the toluene dispersion obtained here was about 5.0%.
Here, Super Beckamine J-820 (manufactured by DIC Corporation) was added as a binder to prepare a conductive polypyrrole paint having a polypyrrole: binder resin of 1: 3 and a solid content of about 5.0%.

Production Example 2: Preparation of reducing polypyrrole paint Anionic surfactant Perex OT-P (manufactured by Kao Corporation) 0.42 mmol, polyoxyethylene alkyl ether nonionic surfactant Emulgen 409P (manufactured by Kao Corporation) 2 .1 mmol, 10 mL of toluene and 100 mL of ion-exchanged water were added, and the mixture was stirred at 20 ° C. until emulsified. To the obtained emulsion, 21.2 mmol of a pyrrole monomer was added, and the mixture was stirred for 1 hour. Then, 6 mmol of ammonium persulfate was added to carry out a polymerization reaction for 2 hours. After completion of the reaction, the organic phase was recovered and washed several times with ion-exchanged water to obtain reducing polypyrrole fine particles having a reducing performance dispersed in toluene. The solid content of the polypyrrole fine particles in the toluene dispersion obtained here was about 5.0%.
Here, Super Beckamine J-820 (manufactured by DIC Corporation) was added as a binder at a ratio of polypyrrole: binder resin = 1: 3 (mass ratio in terms of solid content of both polypyrrole and binder resin). Toluene was added to adjust the concentration of the solid content (polypyrrole and binder resin) to prepare a reducible polypyrrole paint having a solid content of about 5.0%.

Example 1
[Step a1]
The conductive polypyrrole paint prepared in Production Example 1 is thinly coated on a PET film (Cosmoshine A4100 manufactured by Toyobo Co., Ltd.) with a bar coater, dried at 120 ° C. for 5 minutes, and has a thickness of 1 μm. I got
[Step b1]
Subsequently, a negative photosensitive resist OMR-83 (manufactured by Tokyo Ohka Kogyo Co., Ltd.) was coated on the coating film with a bar coater and dried at 85 ° C. for 30 minutes to obtain a resist layer having a thickness of 1 μm. .
[Step c1]
Subsequently, exposure was performed with a high-pressure mercury lamp using a mask having a pattern of L / S = 2 μm / 100 μm.
[Step d1]
Then, it was immersed in an OMR developer (manufactured by Tokyo Ohka Kogyo Co., Ltd.) for 1 minute to perform development, thereby forming a resist pattern.
[Step e1]
Subsequently, the exposed plating underlayer was removed by immersion in a 10% nitric acid solution at 40 ° C. for 3 minutes. [Step f1]
Subsequently, the resist layer was peeled off by immersing it in an OMR rinse solution (manufactured by Tokyo Ohka Kogyo Co., Ltd.) for 1 minute to obtain a patterned plating base layer.
[Step g1]
The film on which the coating film formed in the above step f1 was formed was immersed in a 1 M sodium hydroxide solution at 35 ° C. for 5 minutes to perform a surface treatment (de-doping treatment).
[Step g2]
Next, it was immersed in a 0.02% palladium chloride-0.01% hydrochloric acid aqueous solution at 35 ° C. for 5 minutes, and washed with ion-exchanged water. Next, the film was immersed in an electroless plating bath ATS Adcopper IW bath (manufactured by Okuno Pharmaceutical Co., Ltd.), immersed at 35 ° C. for 10 minutes, and subjected to copper plating to produce a plated product.
FIG. 3 shows an electron micrograph of the surface of a plated product manufactured in Example 1 on which a metal plating film having a line width of 1.8 μm was formed.

Example 2
The resist used in Example 1 was changed to a positive photosensitive resist (S1805 manufactured by Rohm and Haas Co., Ltd.), the developer was changed to (KOH developer), and the stripper was changed to (NaOH stripper). Except for the change, a plated product was manufactured in the same manner as in Example 1.

Example 4
The same method as in Example 1 was used, except that the reducing polypyrrole coating prepared in Production Example 2 was used instead of the conductive polypyrrole coating, and that the dedoping treatment (corresponding to step g1 in Example 1) was not performed. To produce a plated product.

Comparative Example 1
[Production of copper-clad laminate]
100 parts by weight of Chemit K-1294 (manufactured by Toray Industries, Inc.), 20 parts by weight of Staxix (manufactured by Fuji Photo Film Co., Ltd.), and 50 parts by weight of Epicoat Ep871 (manufactured by Japan Epoxy Resin Co., Ltd.) were treated with monochlorobenzene and methyl. The mixture was mixed with a mixed solvent of isobutyl ketone to prepare an adhesive having a solid content of 25%.
Subsequently, the prepared adhesive was coated on a PET film (Cosmoshine A4100 manufactured by Toyobo Co., Ltd.) to a thickness of 5 μm, and a 9 μm thick copper foil F-WS (Furukawa Electric Co., Ltd.) was laminated. Then, it was dried in an oven to produce a copper-clad laminate.
[Photo etching]
Subsequently, a negative photosensitive resist OMR-83 (manufactured by Tokyo Ohka Kogyo Co., Ltd.) is coated on the copper-clad laminate with a bar coater and dried at 85 ° C. for 30 minutes to form a resist layer having a thickness of 1 μm. I got
Subsequently, exposure was performed with a high-pressure mercury lamp using a mask having a pattern of L / S = 2 μm / 100 μm.
Then, it was immersed in an OMR developer (manufactured by Tokyo Ohka Kogyo Co., Ltd.) for 1 minute to perform development, thereby forming a resist pattern.
Subsequently, the exposed copper was immersed in an etching solution composed of an aqueous ferric chloride solution for 3 minutes and removed.
As a result, the copper foil disappeared due to the over-etching, and a plated product having a patterned metal film could not be obtained.

Comparative Example 2
On the copper-clad laminate used in Comparative Example 1, a positive photosensitive resist (S1805 manufactured by Rohm and Haas Co., Ltd.) was coated with a bar coater, dried at 100 ° C. for 10 minutes, and dried to a thickness of 1 μm. A resist layer was obtained.
Subsequently, exposure was performed with a high-pressure mercury lamp using a mask having a pattern of L / S = 2 μm / 100 μm.
Subsequently, the film was immersed in a KOH developer for 1 minute to perform development, thereby forming a resist pattern.
As a result, since the “photoresist after development” disappeared, the subsequent steps (etching, removal of the photoresist) were not performed (as a result, a patterned metal film could not be obtained).

Comparative Example 3
Plating having a patterned copper film in the same manner as in Comparative Example 1 except that copper was sputtered to a thickness of 1 μm on a PET film (Cosmoshine A4100 manufactured by Toyobo Co., Ltd.) instead of the copper-clad laminate. The product was manufactured.

Test example 1
Example 1, 2, at 4 and plated articles manufactured in Comparative Examples 1 and 3, in the plated product produced in the photoresist width after development and Example 1, 2, 4 and Comparative Example 3, patterned metal plating The width was measured and is shown in Table 1.
In addition, the measuring method is as shown below.
In Table 1, A1, A2 and B mean the following.
A1: Conductive polypyrrole fine particles A2: Reducing polypyrrole fine particles B: Super Beckamine J-820 (manufactured by DIC Corporation)
<Measurement method>
1. Measurement of Photoresist Width after Development The photoresist width after development was measured with a microscope (SHP200PC3S manufactured by Shodensha Co., Ltd.) under magnification.
2. Measurement of Patterned Metal Plating Width The final metal film width was measured with a microscope (SHP200PC3S manufactured by Shodensha Co., Ltd.) under magnification.

result:
The photoresist width after development in Examples 1 , 2 and 4 was the same (2.0 μm) in each case as the line width set by the mask, but this was due to reflection from the plating underlayer. It means that there was no exposure.
Further, in Examples 1, 2, and 4 in which wet etching (isotropic) was employed as the etching, although the line width of the metal plating film was reduced due to slight over-etching, the reduced amount was small (2.0 μm → 1.8 μm), and the width of the resulting patterned metal plating film was almost close to the desired line width (see, for example, FIG. 3) .
The ratio Comparative Examples 1, since the layer beneath the resist layer is a copper foil, there is reflected by the copper foil at the time of exposure, and because the resist layer is made from photosensitive negative resist, "development The “post-resist width” became larger than the line width set by the mask (2.0 μm → 4.0 μm).
In Comparative Example 1, the copper foil thickness of the copper-clad laminate was 9.0 μm, which was much larger than the line width set by the mask of 2.0 μm, and wet etching (isotropic) was performed. Because of the adoption, the copper foil disappeared due to over-etching.
In Comparative Example 2, since the layer below the resist layer was a copper foil, there was reflection by the copper foil during exposure, and the resist layer was made of a positive photosensitive resist. The photoresist width is smaller than the line width set by the mask, and the photoresist has completely disappeared.Therefore, it is not possible to obtain a patterned metal film. Did not.
In Comparative Example 3, since the layer below the resist layer was a copper film, there was reflection by the copper film during exposure, and the resist layer was made of a negative photosensitive resist. Is wider than the line width set by the mask (2.0 μm → 4.0 μm).
In Comparative Example 3, the thickness of the copper film formed by sputtering is 1.0 μm, which is considerably smaller than the photoresist width after development of 4.0 μm, so that even in the subsequent wet etching process (isotropic), Only a slight overetching resulted in a patterned metal plating film. However, the width of the patterned metal plating film was not the desired line width (2.0 μm → 3.5 μm).

1: base material 2: plating base layer 3: photoresist layer 3a: negative photoresist layer 3b: positive photoresist layer 4a: negative mask 4b: positive mask 5: metal plating film 6: etching liquid

Claims (4)

A method for producing a plated product in which a patterned metal film having a line width of 2.0 μm or less is formed on a substrate surface,
1) a step a1 of applying a paint containing conductive polypyrrole fine particles and a binder on the surface of a base material to form a plating underlayer having a thickness of 0.1 to 1.0 μm ;
2) a step b1 of forming a photoresist layer on the plating base layer;
3) exposing the photoresist layer through a patterned mask;
4) After the exposure, a step d1 of removing the photoresist layer according to a pattern using a developing solution;
5) a step e1 of removing the plating underlayer exposed by the development by wet etching;
6) Step f1 of removing the photoresist layer remaining on the base material with a rinsing liquid;
7) a step g1 of removing the conductive polypyrrole fine particles contained in the plating underlayer exposed by the removal of the remaining photoresist layer to convert the conductive polypyrrole fine particles into reducible polypyrrole fine particles, and 8) performing the undoping treatment. Step g2 of providing a metal plating film on the plating base layer by electroless plating
Manufacturing method consisting of: 2. The method according to claim 1, wherein the photoresist layer is made of a negative photosensitive resist or a positive photosensitive resist. A method for producing a plated product in which a patterned metal film having a line width of 2.0 μm or less is formed on a substrate surface,
1) a step a2 of applying a paint containing reducing polypyrrole fine particles and a binder on the surface of the base material to form a plating underlayer having a thickness of 0.1 to 1.0 μm ;
2) a step b2 of forming a photoresist layer on the plating base layer;
3) exposing the photoresist layer through a patterned mask;
4) after the exposure, a step d2 of removing the photoresist layer according to a pattern using a developer;
5) a step e2 of removing the plating base layer exposed by the development by wet etching;
6) a step f2 of removing a photoresist layer remaining on the base material with a rinsing liquid; and 7) providing a metal plating film by electroless plating on the plating base layer exposed by removing the remaining photoresist layer. Step g3
Manufacturing method consisting of: 4. The method according to claim 3 , wherein the photoresist layer is made of a negative photosensitive resist or a positive photosensitive resist.