JP2003077352A - Manufacturing method of conductive pattern film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method which enables to simply manufacture a conductive film by using a solution composed of only metal fine particles and solvent with few treatment process at low cost, and enables to manufacture a necessary conductive pattern film with low heat treatment temperature. SOLUTION: As the manufacturing method of a conductive pattern film, a coagulation promotion layer having pores is formed on a base material, and the minute holes are filled with solvent, and monomer with polymerizing characteristics is painted on the above, and a polymer layer is formed by polymerizing and drying the painted layer excluding a prescribed conductive pattern forming part, and a metal particle solution is painted on the surface of the polymer layer and non-polymer layer, and dried by heat treatment, and the conductive pattern layer is formed on the coagulation promotion layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic circuit requiring a fine conductive pattern film, and an EL, P requiring a conductive pattern having a fine opening and having a high visible light transmittance.
The present invention relates to a method for producing a conductive pattern film useful as an electromagnetic wave shielding film and a transparent electrode of various display devices such as DP, CRT, LCD, or a transparent electrode of a solar cell.

[0002]

2. Description of the Related Art Fine conductive pattern films are useful as wiring for electronic circuits, transparent electrodes, electromagnetic wave shielding films, etc., and various materials and manufacturing methods have been conventionally used. In a commonly used method for producing a fine conductive pattern film, a metal thin film formed on the upper surface of a substrate is subjected to processes such as resist coating, pre-baking, and exposure to remove unnecessary portions and perform etching to obtain a desired pattern shape. And finally, the resist is removed by peeling or melting.

In recent years, a wet process typified by wet coating has been actively tried as a method for forming a conductive layer at low cost. As the wet coating material, a material in which a conductive material such as ITO fine particles or metal fine particles is dispersed in a dispersion medium together with a binder and a dispersion stabilizer is generally used.

Among them, the conductive film using ITO fine particles is
Due to the grain boundary resistance between the fine particles in the coating layer, the achievable surface resistance is at least 1000 Ω / □ to 10000 Ω / □, and to obtain the level of conductivity required for electronic circuit wiring, electromagnetic wave shielding, or electrodes. I can't. Also, 350
Although it is possible to reduce the resistance by high-temperature heat treatment at ℃ to 400 ℃ or more, the base material that can handle the temperature is limited to glass.

On the other hand, the metal fine particles have a volume specific resistance smaller than that of the above-mentioned conductive oxide by 1/100 order, and in addition to the conductive oxide fine particles or the bulk state of the above-mentioned metal fine particles, It is generally known that fusion of particles occurs at low temperature. For this reason, when the metal fine particles are used as a conductive material for wet coating, it is possible to obtain the level of conductivity required for the above-mentioned applications by heat treatment at a relatively low temperature, and it has recently attracted attention as a conductive material. There is.

[0006]

However, in the above-mentioned patterning step, the number of processing steps is large, so that the cost is increased and the defective product rate is further increased. In addition, when forming the metal thin film during the treatment process, vapor deposition, sputtering method, plating method, or the like must be adopted, which causes further cost increase. Further, even when using the metal fine particles, the temperature required to develop the level of conductivity required for the application is 150 to 200 ° C. or higher, and when considering the heat resistance of the film substrate, It cannot be said that the temperature can be sufficiently processed, and the problem that the usable substrate is limited has not yet been solved. Then, when using a coating liquid containing metal fine particles, if the metal fine particles and a compound other than the solvent are mixed, the coating suitability is increased, but aggregation of the metal fine particles easily occurs and liquid stability is poor, and in general, The conductivity will drop. However, a solution containing only metal fine particles and a solvent has a problem that its suitability for application to general substrates is extremely poor.

The present invention has been made in view of this problem, has a small number of processing steps, is simple and inexpensive, and can form a conductive film by using a solution of only metal fine particles and a solvent, and An object of the present invention is to provide a method capable of producing a necessary conductive pattern film at a low heat treatment temperature.

[0008]

The invention according to claim 1 provides a coagulation promoting layer having pores on a substrate, filling the pores of the coagulation promoting layer with a solvent, and then polymerizing the monomer. A coating solution containing the above, except for the predetermined conductive pattern forming portion on the top, polymerization, and dried to form a polymerized layer, the polymerized layer and the non-polymerized layer surface, the metal fine particle solution is applied, heat treatment dried. The method for producing a conductive pattern film comprises forming a conductive pattern layer on the aggregation promoting layer.

According to a second aspect of the present invention, an aggregation promoting layer having pores is provided on a base material, the pores of the aggregation promoting layer are filled with a solvent, and then the conductive pattern forming portion is removed, and the polymerizable composition is polymerized. A coating liquid containing a monomer is applied, polymerized and dried to form a polymerized layer, a metal fine particle solution is applied to the surface of the polymerized layer and the aggregation promoting layer, and heat treatment is dried to form a conductive pattern layer on the aggregation promoting layer. It is a method of manufacturing a conductive pattern film, which is characterized in that the conductive pattern film is formed.

The invention according to claim 3 is characterized in that a solvent permeation layer is formed on a substrate before the aggregation promoting layer is provided. It is a manufacturing method of a pattern film.

The invention according to claim 4 is the method for producing a conductive pattern film according to any one of claims 1 to 3, wherein the film thickness of the aggregation promoting layer is in the range of 10 to 10,000 nm. Is.

A fifth aspect of the present invention is the method for producing a conductive pattern film according to the third or fourth aspect, wherein the thickness of the solvent permeation layer is in the range of 1 to 100 μm.

In a sixth aspect of the present invention, the metal fine particles are any of Ag, Al, Cu, Au, Pt and Pd.
Alternatively, the method for producing a conductive pattern film according to any one of claims 1 to 5, which is a combination or an alloy of two or more kinds thereof.

The invention according to claim 7 is the method for producing a conductive pattern film according to any one of claims 1 to 6, wherein the heat treatment temperature is 150 ° C. or lower.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be specifically described below.

First, in the present invention, the aggregation promoting layer 3 having pores composed of one or more layers containing inorganic oxide fine particles is formed on the substrate 1, and then the solvent is added to the aggregation promoting layer 3. And then a solution containing a polymerizable monomer is applied to form a coating liquid layer 4
Is formed, and except for a predetermined conductive pattern forming portion, polymerization and drying are performed to form a patterned surface layer 5. Then, a metal fine particle solution containing at least metal fine particles and a solvent is applied onto the non-polymerized portion 6 and the surface layer 5 to form a conductive pattern layer including the aggregation layer 7 on the aggregation promoting layer 3. A conductive pattern film is manufactured.

The above-mentioned surface layer 5 was prepared by polymerizing the layer 4 of the solution containing the polymerizable monomer, which was provided on the entire surface, except for the portion where the conductive pattern was formed. A layer of a solution containing a polymerizable monomer may be formed only on the exposed portion to form a polymerized surface layer.

Next, it is preferable to provide not only the aggregation promoting layer 3 but also the solvent permeation layer 2 and the aggregation promoting layer 3 directly on the substrate 1. Note that, although FIG. 1 shows a step of forming a conductive pattern film in the case where one layer of the solvent permeation layer 2 and one layer of the aggregation promotion layer 3 are provided, the present invention is not limited to this configuration.

As described above, in the surface layer 5 portion formed of the polymerized layer, the permeation of the solvent of the solution containing the polymerized monomer is obstructed and the conductive layer is not formed, but the non-patterned portion, that is, the aggregation promoting layer. In the third portion, the solvent mainly permeates selectively into the pores, and accordingly, the aggregation of the metal fine particles is promoted in the portion close to the surface, and the metal fine particle aggregation layer 7 appropriately patterned has a low heat treatment temperature. Can be obtained at.

Here, the base material 1 in the present invention is not particularly limited, and various glass base materials and known plastic films or sheets having appropriate mechanical rigidity may be appropriately selected and used. You can Specific examples include films of polyimide, polyester, polyethylene, polypropylene, triacetyl cellulose, diacetyl cellulose and the like.

From the viewpoint of fine processing, the particle size of the metal particles used in the metal particle solution for forming the conductive layer is preferably 50 nm or less. Primary particle size is 50
When it is at least nm, the pattern resolution is likely to be lowered.

As the metal species of the metal fine particles, Ag,
Examples thereof include Au, Cu, Al, Pd, and the like, and particularly Ag from the viewpoint of conductivity and visible light transmittance in display applications.
Those mainly composed of are preferred. Further, in order to improve color tone and chemical stability, two or more kinds of alloys containing Ag may be used.

For the preparation of the fine metal particles, Carey-
The method published by Lea in 1889 (Am. J. Sc
i. , Vol. 37, pp. It can be manufactured relatively easily by many known techniques represented by 491, 1889).

The metal fine particle solution contains, in addition to the solvent, a dispersant such as citric acid used at the time of preparation, a reducing agent which is contained in a trace amount and which is not washed, and other additives. Since it may cause deterioration of metal dispersion performance and deterioration of conductivity after coating, it is preferable not to add any other additive.

As described above, it is preferable not to add an additive to the metal fine particle solution, but for the purpose of improving dispersibility of metal fine particles, coating suitability, coating strength, etc., a dispersion stabilizer or a binder is used. May be added.

Examples of the additives include carboxylic acids such as citric acid, stearic acid, lauric acid and oleic acid, sulfonic acids such as phenyldiazosulfonic acid and dodecylbenzenesulfonic acid, polyvinyl alcohol, polyvinylpyrrolidone and polyethylene glycol. It is preferable to use the water-soluble polymer compound.

The solvent used for the metal fine particle solution is water; methanol, ethanol, propanol, butanol, diacetone alcohol, ethylene glycol,
Alcohols such as hexylene glycol; Esters such as methyl acetate and ethyl acetate; Diethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, etc. Kinds; ketones such as acetone, methyl ethyl ketone, acetylacetone, acetoacetic acid ester, and the like. These may be used alone or in combination of two or more.

The aggregation promoting layer having fine pores containing the inorganic oxide fine particles preferably contains 20% by weight or more of the inorganic oxide fine particles, and the higher the content, the more preferable.

With respect to the inorganic oxide fine particles contained in the solvent permeation layer, if the particle size is too small, the gaps between the particles will almost disappear, while if too large, the gaps between the particles will become large, so that it is appropriate. The penetration of the solvent is less likely to occur, and the appropriate aggregation of the metal fine particles in the aggregation promoting layer is less likely to occur. Therefore, the particle diameter is preferably in the range of 10 nm to 100 μm, more preferably 100 nm to 10 μm. Furthermore, the structure is flaky, feathery,
It is preferably a plate-like shape.

The inorganic oxide species of the inorganic oxide particulates contained in the solvent permeation layer are not particularly limited, and general silicon oxide particulates and aluminum oxide particulates can be used.

Other components contained in the solvent permeation layer include binder and / or binder from the viewpoint of coating suitability and coating strength.
Or preferably containing a binder precursor monomer,
Examples of binders include, but are not limited to, water-soluble polymers such as polyvinyl alcohol and polyethylene glycol, thermosetting resins and monomers, and photocurable resins and monomers.

Binder and / or included in the solvent permeation layer
If the content of the binder precursor monomer is too large, the gaps between the inorganic oxide fine particles will disappear, and if it is too small, the coating suitability and the coating strength will be poor. On the other hand, it is preferably in the range of 1 to 100 parts by weight,
More preferably, it is in the range of 5 to 20 parts by weight.

The thickness of the solvent permeation layer is 100 n.
The range of m to 100 μm is preferable, and 1 is more preferable.
It is in the range of μm to 50 μm.

With respect to the inorganic oxide fine particles contained in the aggregation promoting layer, if the particle size is too small, the gaps between the particles will almost disappear, while if too large, the gaps between the particles will become large, and thus the metal fine particles are suitable. Since it is difficult to cause such aggregation, the particle diameter is preferably in the range of 1 nm to 10 μm, more preferably 10 nm to 1 μm. Further, the structure preferably has a shape close to a sphere.

The inorganic oxide species of the inorganic oxide fine particles contained in the aggregation promoting layer are not particularly limited, and general silicon oxide fine particles and aluminum oxide fine particles can be used.

Other components contained in the aggregation promoting layer include a binder and / or a binder from the viewpoint of coating suitability and coating strength.
Or preferably containing a binder precursor monomer,
Examples of the binder include, but are not limited to, water-soluble polymers such as polyvinyl alcohol and polyethylene glycol, thermosetting resins and monomers, and photocurable resins and monomers.

The binder contained in the aggregation promoting layer and / or
If the content of the binder precursor monomer is too large, the gaps between the inorganic oxide fine particles will disappear, while if it is too small, the coating suitability and coating strength will be poor. The amount is preferably 1 to 100 parts by weight, more preferably 5 to 20 parts by weight, based on parts by weight.

The aggregation promoting layer has a thickness of 5 nm to
The range is preferably 10 μm, more preferably 10 nm.
˜2 μm.

The method of polymerizing the polymerizable monomer is as follows:
Although not particularly limited, a polymerization method by pattern exposure is preferable because it is necessary to polymerize in a desired pattern, and various UV light sources, X
A line light source, an electron beam light source, etc. can be used. Also,
There is no particular limitation as long as it can polymerize the polymerizable monomer. Although it is not necessary when using a method such as electron beam drawing, when using a mask for the pattern light, if the mask is a transparent portion of the light source to be used and a difficult-to-transparent portion is patterned, It is not particularly limited.

As the above-mentioned polymerizable monomer, one in which the polymerization proceeds by using the light source used and / or one in which the polymerization proceeds by using the light source used by adding an additive such as a polymerization initiator. It is not particularly limited as long as it is, and examples thereof include styrene, styrene derivatives, and various (meth) acrylates.

The solvent that fills the pores is not particularly limited, but it is preferable that the polymerizable monomer be maintained near the outermost surface, and therefore it is preferable that the solvent has little compatibility with the polymerizable monomer. For example, when styrene, a styrene derivative, various (meth) acrylates, etc. are used as the polymerizable monomer, it is preferable to use water or the like.

As the coating liquid containing the above-mentioned polymerizable monomer,
A solvent, a polymerization initiator, a leveling agent, a defoaming agent, a viscosity adjusting agent and the like may be contained.

The solvent used in the coating liquid containing the polymerizable monomer is not particularly limited, but it is preferable to maintain the polymerizable monomer in the vicinity of the outermost surface, so that the solvent is compatible with the polymerizable monomer. And it is preferable that there is not much compatibility with the solvent that fills the pores. For example, styrene, a styrene derivative, and various (meth) acrylates are used as the polymerizable monomer, and water is used as the solvent that fills the pores. If is used, it is preferable to use methyl ethyl ketone, toluene, hexane, various ethers, or the like.

The polymerization initiator used in the coating liquid containing the polymerizable monomer is not particularly limited, but is particularly limited as long as the polymerization of the polymerizable monomer proceeds using the light source used. It is not something that will be done.

The solvent permeation layer, the aggregation promoting layer, the coating solution containing a polymerizable monomer and the metal fine particle solution may be applied by a gravure coating method, a spin coating method, an ink jet method, a roll coating method, a spray method, a bar coating method or a dip. A normal film forming method such as a method can be used.

After coating the metal fine particles, various overcoat layers may be further provided thereon to provide various functions.

[0047]

EXAMPLES A. Preparation of Silver Fine Particle Aqueous Solution The above-mentioned method announced by Carey-Lea in 1889 (Am. J. Sci., Vol.37, pp.491,
1889) to prepare an aqueous silver particle dispersion solution. T
The average primary particle diameter was about 7 nm by EM observation. Further, it was prepared by diluting with distilled water so that the Ag concentration became 7% by weight.

B. Preparation of coating solution for forming solvent penetration layer 25 parts by weight of flaky alumina sol aqueous solution (Alumina sol 520 manufactured by Nissan Chemical Industries, alumina content 20% by weight) and polyvinyl alcohol (PVA21 manufactured by Kuraray)
5 parts by weight of the 10% by weight aqueous solution of 7) and 10 parts by weight of distilled water
The solution mixed at a ratio of 0 part by weight was prepared by stirring for 30 minutes.

C. Preparation of coating liquid for forming aggregation promoting layer 25 parts by weight of spherical silica sol aqueous solution (Snowtex Ak, manufactured by Nissan Chemical Industries, silica content 20% by weight) and 5 parts by weight of 10% by weight aqueous solution of polyvinyl alcohol (PVA217 by Kuraray) and A solution prepared by mixing 100 parts by weight of distilled water was prepared by stirring for 30 minutes.

D. Preparation of coating liquid containing polymerizable monomer 20 parts by weight of pentaerythritol triacrylate (light acrylate PE-3A manufactured by Kyoeisha Chemical Co., Ltd.) and 8 parts of methyl ethyl ketone (VC102 manufactured by Toyo Ink Mfg. Co., Ltd.)
0 parts by weight and a photopolymerization initiator (Irba manufactured by Ciba Geigy)
Gacure 651) was mixed at a ratio of 1 part by weight to prepare a solution which was stirred for 30 minutes.

E. Exposure Method Exposure was performed using a high pressure mercury lamp with an exposure amount of 200 mJ / cm ^ 2. As the mask, a photomask having a stripe pattern of L / S = 10/10 μm was used.

(Example 1) A PET film (A4300 manufactured by Toyobo Co., Ltd.) was coated with a coating solution for forming a solvent permeation layer by a wire bar coating method so that the film thickness after drying was 10 μm, and the coating was carried out at 120 ° C. for 1 hour. After drying for a minute, a solvent permeation layer was formed. A coating solution for forming an aggregation promoting layer was applied onto the solvent permeation layer by a wire bar coating method so that the film thickness after drying was 0.1 μm, and dried at 120 ° C. for 1 minute to form an aggregation promoting layer. . Distilled water is applied to the laminate by the wire bar coating method to fill the pores,
A coating liquid containing a polymerizable monomer was applied by a wire bar coating method to a wet film thickness of 10 μm, exposed by a mask exposure method, and dried at 120 ° C. for 1 minute to form a surface layer. An aqueous solution of fine silver particles was applied to this surface by a wire bar coating method to obtain a wet film thickness of 1 μm.
And then dried at 120 ° C. for 1 minute to prepare a target film.

Comparative Example 1 A film was prepared in the same manner as in Example 1 except that the coating solution for forming a solvent permeation layer was not applied and dried.

Comparative Example 2 A film was prepared in the same manner as in Example 1 except that the coating liquid for forming the aggregation promoting layer was not coated and dried.

(Comparative Example 3) A film was prepared in the same manner as in Example 1 except that water was not applied and dried on the laminate of the solvent permeation layer and the aggregation promoting layer.

The characteristics of the conductive film thus prepared are shown in Table 1 below.
Shown in.

[0057]

[Table 1]

From the results shown in Table 1 above, the laminate of the solvent permeation layer and the aggregation promoting layer was filled with water to fill the pores, and the coating liquid containing the polymerizable monomer was applied to the upper surface of the laminate, followed by pattern exposure and drying, By the application of an aqueous solution of silver fine particles, a good pattern shape is exhibited as compared with the case where there is no solvent permeation layer, the case where there is no aggregation promoting layer, and the case where the step of filling the pores with the application of water is not performed, and the silver The agglomeration state of the fine particles was well controlled, and a good pattern shape and conductivity were exhibited.

[0059]

INDUSTRIAL APPLICABILITY The fine conductive pattern film of the present invention is formed by applying water to a layer on which agglomeration of metal fine particles is formed, and preferably a base material provided with a layer for promoting solvent penetration under the layer. By filling the pores with a coating solution containing a polymerizable monomer on the upper surface, pattern exposure, drying, and coating with an aqueous solution of silver fine particles, the resist removal step can be omitted as compared with the conventional manufacturing method by photolithography. In addition, a good pattern shape and conductivity are exhibited.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an example of a process of forming a fine conductive pattern layer of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Substrate, 2 ... Solvent permeation layer, 3 ... Aggregation promoting layer, 4 ... Coating liquid layer containing a polymerizable monomer, 5 ... Surface layer, 6 ... Non-polymerization part,
7 ... Metal colloid aggregation layer

Continued front page    F-term (reference) 4D075 AE03 AE27 BB24Z BB40Y                       BB46Y BB47Y BB48Y BB92Z                       BB93Z CA22 CB11 DA04                       DA06 DB13 DB33 DB36 DB48                       DB53 DC21 DC24 EA06 EA10                       EA21 EB01 EB14 EB19 EB22                       EB24 EC10                 5G323 CA00

Claims (7)

[Claims] 1. A coagulation promoting layer having pores is provided on a substrate,
The pores of this aggregation promoting layer are filled with a solvent, and then a coating liquid containing a polymerizable monomer is applied, and a predetermined conductive pattern forming portion is removed thereon, and polymerization and drying are performed to form a polymerization layer, and the polymerization is performed. A method for producing a conductive pattern film, which comprises applying a fine metal particle solution to the surfaces of the layer and the non-polymerized layer, heating and drying the solution to form a conductive pattern layer on the aggregation promoting layer. 2. A coagulation promoting layer having pores is provided on a base material,
The pores of this aggregation promoting layer are filled with a solvent, and then the conductive pattern forming part is removed, and a coating liquid containing a polymerizable monomer is applied, polymerized and dried to form a polymerized layer, and the polymerized layer and aggregation are promoted. A method for producing a conductive pattern film, which comprises applying a solution of fine metal particles on a layer surface, heating and drying the solution, and forming a conductive pattern layer on the aggregation promoting layer. 3. The method for producing a conductive pattern film according to claim 1, wherein a solvent permeation layer is formed on the base material before the aggregation promoting layer is provided. 4. The film thickness of the aggregation promoting layer is 10 to 1000.
The method for producing a conductive pattern film according to claim 1, wherein the conductive pattern film has a thickness of 0 nm. 5. The solvent permeation layer has a thickness of 1 to 100 μm.
5. The method for producing a conductive pattern film according to claim 3, wherein the conductive pattern film is in the range. 6. The fine metal particles are Ag, Al, Cu, A
6. The method for producing a conductive pattern film according to claim 1, wherein any one of u, Pt, and Pd, or a combination or alloy of two or more kinds thereof is used. 7. The method for producing a conductive pattern film according to claim 1, wherein the heat treatment temperature is 150 ° C. or lower.