JP7460047B2 - Method for producing metal pattern using electrophotographic toner - Google Patents

Description

The present invention relates to a method for producing metal patterns such as electronic circuits using electrophotographic toner, where the pattern formation is related to electrostatic printer technology, such as electrophotography, and the formation of a conductive metal layer is related to plating technology.

The subtractive method using photoresist has long been used to create metal patterns for electronic circuits, such as printed circuit boards. First, a resist layer is formed on a metal layer formed over the entire surface of the substrate, and ultraviolet light is irradiated through a mask with a pattern to harden only the portion of the resist layer that corresponds to the pattern, after which the unhardened portion of the resist layer is removed. Next, the metal layer other than the pattern is dissolved and removed, and the resist layer is subsequently removed to create a metal pattern for electronic circuits, etc. However, this method involves many steps, and storing and managing the masks is difficult, so there is a demand to reduce the number of steps as much as possible and to digitize the pattern data.

Various methods have been proposed as countermeasures, and some of them have been put into practical use, but no method has emerged that can replace conventional methods. It is said that the ultimate in this field is the fully additive method. It is also said that if this becomes a reality, the cost will be halved compared to conventional methods.
The additive method is a method in which metal is added only to the necessary parts from the beginning, as opposed to the subtractive method.

There are two possible ways to realize the additive method. The first method is, as the name suggests, a method of directly applying metal to only the necessary parts of the substrate surface. However, it is not easy to meet the specifications required for printed circuit boards, as both fineness and low electrical resistance are required. It is nearly impossible to cut out and paste metal sheets, or to create metal patterns using metal powder. Furthermore, if the metal is turned into powder, contact resistance will occur between the metal powders, and the high conductivity that is originally required will not be obtained. The only way to obtain the original conductivity of metal is to melt the metal and integrate the powder. This usually requires heating at 500°C to 1000°C, and is impossible to achieve unless the substrate is something like ceramic.

However, this barrier was broken with the advent of nanometals as seen in Patent Document 1. When metal particles are made small to the nano-order, they melt at around 300°C, and if the temperature is lowered to this level, they can be formed on polyimide films used as flexible substrates. It seemed that the additive method would be established all at once, but unfortunately no practical pattern formation method using this nanometal has been established. The inkjet method was the only method that seemed simple and effective, but it is difficult to create a thick metal layer using the inkjet method. Taking printed circuit boards as an example, one of the required performances is not only the conductivity of the circuit, but also the ability to flow a certain amount of current. In order to increase the wiring density of the circuit, the line width must be made narrower, and in order to allow more current to flow, it is necessary to make the metal layer thicker. Although it depends on the circuit conditions, the thickness is required to be several micrometers or more at most. In this respect, the metal layer created using the inkjet method using nano ink is thin and cannot conduct large currents. Although it is possible to increase the thickness to some extent by overwriting, it is impossible to put it to practical use in terms of speed and accuracy. In this way, the possibility of further development using the first method is not visible.

The second method to realize the additive method already provides the inherent conductivity of metal required for printed circuit boards, the thickness of the metal layer can be adjusted depending on the purpose, and it has a long history as an industrial method and the technology has been established. This is a method using a metal plating method. If plating can be applied only to the desired pattern, it is a fully additive method. However, unless the pattern forming method has a resolution comparable to the conventional subtractive method using photoresist, it cannot replace the conventional method. Patent Document 2 discloses a technology that has this potential. The method involves creating an electrostatic pattern for an electronic circuit using electrophotography, developing and transferring it using toner with a catalytic metal such as palladium attached to the surface of a powdered resin, and then creating a metal pattern using plating. Although there have been proposals for this method for some time, electrophotography is a method in which an electrostatic latent image on a photoreceptor is developed with electrostatically charged toner, and then transferred to a transfer material using an electrostatic electric field. If there is a conductive metal on the surface of the powder toner, there is a risk of destroying the electrostatic latent image or causing transfer failure, so this method could not be practical.
Patent Document 2 proposes that the above problem can be solved by adsorbing catalytic metal fine particles onto the surface of metal oxide fine particles and arranging the fine particles in a matrix on the surface of a resin toner.

Another method with high resolution is to use a patterned mask and irradiate it with vacuum ultraviolet light, electron beams, X-rays, etc. to cause chemical changes on the surface of the base material, and catalyze only those areas. Methods of attaching metal and plating have also been proposed for some time. Although these have resolution comparable to subtractive methods using photoresists, they have not been widely adopted as industrial equipment. The reality is that it is limited to special industries such as patterns for semiconductors. The reason for this is probably that the light source is special, the mask base material that transmits the light, and the material of the mask part that blocks it are more specific and expensive than conventional ones, and the process of using the mask is different from the conventional one. This is thought to be because it is not suitable for industrial equipment that attempts to process large areas at high speeds.

Electrophotography is an established technology that has been used in copiers, printers, digital printers, and everything from consumer devices to industrial equipment. The resolution of the photoconductor is said to be 100 lines/mm (2500 dpi), meaning it can reproduce 10 μm lines. Although this has not yet been commercialized, it is said that a high-gamma photoconductor can reproduce 5000 dpi. 1200 dpi specifications are becoming common even in consumer devices. If a system with this level of capability could freely create patterns, it could become a system that can be used in most printed circuit board fields.
So, can Patent Document 2 be the final product? Unfortunately, I have to say that it is probably not. The reason is that toner production and processing are complicated, unreasonable, and wasteful. In other words, it is expected that toner production and plating pre-processing will be quite costly. First of all, palladium is generally used as a catalyst metal for copper plating. Palladium is a precious metal and is expensive. And if it is made into a nano-metal, it will be even more expensive. The production method of attaching the metal to the fine toner surface in a special arrangement will also be costly. Furthermore, when the toner is fixed, some of the metal will be buried inside the resin. This will not function as a catalyst. For this reason, Patent Document 2 proposes a process to treat the toner surface after fixing to bring the internal metal to the surface.
Also, it is impossible to use 100% of the toner developer for images, and some toner will always be wasted, scattered, or stuck to the surface. This happens in any printing system, and while it is not a big deal if it is ordinary ink or toner, if it is precious metals, it becomes a bit of a problem in terms of cost.

Japanese Patent Application Publication No. 2008-280592 JP 2007-134422 A Patent Application No. 2018-188998

As mentioned above, although it is an electrophotographic system with high resolution, it is not good for the system to include metal in the toner, and if it is nanometal or precious metal, it is not good from a cost standpoint. This is something I would like to avoid even more.
Common sense dictates that it is most desirable from both system and cost standpoints for the toner to be composed only of resin, as usual. The challenge then becomes how to create a system that can be connected to plating even though it is a resin. Furthermore, it is desired that the metal plating and the base material have strong adhesion.

The present invention provides a practical, high-definition metal pattern fabrication method that is a full additive method, using electrophotography, which can achieve resolution comparable to or greater than that of conventional subtractive methods that use photoresists, and plating, which is an excellent method in terms of both electrical properties and material costs.
To achieve this, the following measures are used:
(1) The pattern is formed by electrostatic pattern forming means, typically electrophotography, which is fast, has high resolution and allows continuous output.
(2) The means for developing the electrostatic pattern is toner composed only of resin, the same as conventional electrophotographic toner. The toner is composed of resin with ligands that incorporate metals to form complexes, and has the function of supporting the plating catalyst metal. The fixed toner is composed of resin that is resistant to both highly acidic catalyst solutions and highly alkaline plating solutions.
(3) The toner that has been directly developed or transferred onto the substrate is fixed by means of heat, light, electromagnetic waves, etc. The toner has a hardening property, and by hardening and fixing, the toner has strong adhesion to the substrate and also has the acid resistance and alkali resistance required for subsequent processes.
(4) As a pre-plating treatment means, a means is used in which the substrate to which the toner has been fixed is immersed in a metal salt catalyst liquid to adsorb the catalyst metal or catalyst metal ions.
(5) The pretreated substrate is immersed in a desired electroless plating solution to form a desired metal pattern on the substrate.

Since the toner used in the present invention is composed only of resin and does not contain any metal, accurate development and transfer can be performed without destroying the electrostatic pattern, similar to conventional electrophotographic toners. Then, the catalytic metal is adsorbed only on the toner portion, and only that portion is plated with metal in a step similar to the conventional electroless plating pretreatment method, without requiring the complicated process of plating on a conventional insulator. The patterned metal plating also has strong adhesion to the substrate without the need for post-treatment. Therefore, a low-cost fully additive method is realized in which neither the catalyst metal nor the plated metal is wasted, and a metal pattern that is faithful to the original high-definition electrostatic pattern can be obtained.

A method for producing static electricity patterns using intaglio printing in hand experiments Nickel-plated photograph on fused toner Enlarged photo of plated thin line area An example of electrophotographic production of toner patterns on a continuous substrate An example of creating a metal pattern by plating a continuous substrate with a toner pattern.

As mentioned above, the present invention basically proposes a method of developing, transferring, and fixing an electrostatic pattern with a completely resinous toner that has the function of a toner used in the electrophotographic method of faithfully manifesting an electrostatic latent image, and further has the ability to carry a catalytic metal for plating pretreatment, and then adsorbs the catalytic metal to the fixed toner part, and plates it to create a metal pattern. In other words, the present invention first proposes a method of forming a pattern with static electricity and then forming a toner pattern on the target substrate. The substrate is not a substrate with copper foil attached or a copper film formed over the entire surface by sputtering or plating as in the past, but a substrate with high electrical insulation. It may be in the form of a plate or a film. In the electrophotographic method, an electrostatic pattern is generally formed on a photoreceptor, and then the toner is transferred from the photoreceptor to the target substrate in order to develop it with charged toner, but there is also a method of drawing an electrostatic pattern directly on the substrate, in which case the substrate is directly developed with toner. However, when drawing an electrostatic pattern directly on the substrate, the charge retention of the electrostatic charge is more affected by the surface condition of the substrate than by the electrophotographic photoreceptor, and in particular, the effect of moisture is large, so this needs to be taken into consideration. One effective solution is to apply a water-repellent coating to the substrate surface. Regardless of the method, the first step is to fix the desired toner pattern onto the substrate. After that, the metal pattern is formed using a standard electroless plating method.

[Static pattern]
Electrophotography is a technology invented for copying machines, and is a plateless variable printing method that can output different images for each page at high speed. For this reason, the photoconductor, which is an optical semiconductor, has high resolution and excellent characteristics. However, unless the purpose is prototyping for development, there is almost no need for it to be variable if the purpose is to mass-produce the same patterns as printed circuit boards as industrial equipment. There is no problem with using plates like in printing presses, and in fact there is a possibility of creating a system that is faster, more accurate, and more durable than plateless systems.
It is possible to make a plate that can be charged only in the pattern portion of a plate. This is an effective manufacturing method because it does not require the use of a special device called an electrophotographic photoreceptor. Also, as long as toner development is possible, the plate is not limited to an electrostatic pattern. For example, even if a pattern is formed on an insulating substrate with a conductive material such as metal, the insulating toner will adhere if a polarity potential opposite to the charging polarity of the toner is applied to the conductive material, and it can be transferred to a transfer material by applying a reverse electric field. This is because the insulating toner has a charge distributed over the entire surface of each particle, and does not lose charge even when it comes into contact with a conductive material. Since the toner in the present invention is also an insulating toner, there is no problem even if the pattern is formed with a conductive material. Furthermore, even if an insulating protective film or toner release treatment is applied to the surface of the pattern formed with the conductive material, it hardly interferes with development, and is effective in durability and transferability.

If an electrostatic pattern could be formed directly on the substrate on which the metal pattern is to be formed, the transfer process could be omitted and image degradation due to transfer could be avoided. However, although there have been examples in the past of practical devices for directly creating electrostatic patterns, they are not currently being manufactured due to their low resolution. Also, a copying machine using a method known as electrostatic transfer, in which the electrostatic charge of a charged pattern created on a photoconductor by electrophotography is directly transferred to special paper and the paper is developed, has been put to practical use, but this is no longer manufactured. Both of these demonstrate the difficulty of forming a high-resolution electrostatic pattern directly on an insulating substrate.
However, technology has always made the impossible possible. The inventors have invented a method to create electrostatic patterns with a quality higher than that of the current electrophotographic method directly on an insulating substrate. When combined with the present invention, it is possible to print high-density printed circuits on polyimide substrates and PET substrates, and to print so-called metal mesh circuits for touch panel films that require fine lines of 10 μm or less.

[Toner Composition]
The toner used is a functional toner made with a new composition. It is not a "platable toner in which a catalytic metal is added to a toner resin" as previously proposed, but a "platable toner that adsorbs catalytic metal or catalytic metal ions". In other words, since the toner itself does not contain catalytic metal, it is not possible to plate only the toner part when it is fixed to the substrate. The toner according to the present invention is immersed in a catalytic solution, so that the catalytic metal is adsorbed only to the toner, and then immersed in an electroless plating solution, so that the toner part is plated with metal. The toner is composed of a resin necessary for the original function of electrophotographic toner, and is established by introducing a group having a ligand that incorporates a metal into a part of the resin and forms a complex. Furthermore, in order to withstand the highly acidic catalytic solution and the highly alkaline plating solution in the next process, and to increase adhesion to the substrate, it is given the property of hardening when fixed. In the world of chemical reactions, it is common to treat catalytic metals as complexes. The complex that holds the metal is strong, and the metal will not come off unless another chemical reaction occurs. And since the resin that holds the metal is fixed to the substrate as a hardened toner and firmly adheres to it, the plated metal will firmly adhere to the substrate.

The toner can be either a dry developed toner or a liquid developed toner. The minimum particle size of dry development toner is about 5 μm, and the particle size of liquid development toner is submicron (about 0.2 to 0.8 μm) except in special cases. When expressing the required minimum line width on an image by overlapping particles, it is said that the particle diameter needs to be 1/10 or less of the line width.
When the dry development toner particle size and the latent image dot size are 5 μm (equivalent to 5000 dpi), a 50 μm line (equivalent to 500 dpi) is the resolution limit (guaranteeing good linearity at the end of the line). Good linearity at the end of the line becomes more important as the frequency used in printed circuits becomes higher. If higher resolution is desired, liquid developing toner is suitable.
Since the particle size of liquid developing toner is submicron (approximately 0.2 to 0.8 μm) except in special cases, it is possible to obtain a resolution 10 times or more. In other words, lines and dots with a width of 5 μm can be obtained with satisfactory resolution. Here, one specific configuration will be shown using a liquid developing toner as a representative that can provide such resolution.

The components of the liquid developing toner include insulating resin particles composed of a core resin and a shell resin covering the core, a dispersant, an insulating solvent, and, if necessary, a charge control material such as a metal soap.
This liquid developing toner contains an electron-donating functional group that selectively adsorbs a catalyst metal (ion) on either the core resin or the shell resin. The functional group (that is, a group having a ligand that incorporates a metal to form a complex) includes an amino group, a phosphono group, a carboxyl group, a hydroxyl group, a thiol group, etc., which are composed of atoms with a lone pair of electrons. Applicable. Amino groups are particularly effective. Amino groups also include nitrogen-containing compounds such as pyridine, azole, triazole, imidazole, and the like.
It contains an electron-donating functional group of 0.1 mM/g or more (preferably 0.2 mM/g or more). In the electroless plating process, electroless plating (strongly alkaline) is performed after catalyst application (strongly acidic), so the pattern formed by the toner is required to have high acid resistance and alkali resistance.
Therefore, the present liquid developing toner contains a crosslinkable functional group, such as an isocyanate group, a blocked isocyanate group, or a glycidyl group, that reacts with the electron-donating functional group in either the core resin or the shell resin. When a liquid developing toner fixes an electrostatic latent image after developing it, the developed resin layer becomes three-dimensional due to the crosslinking between the electron-donating functional group and the crosslinking functional group, resulting in significant alkali resistance, acid resistance, and chemical resistance. improve. The present liquid developing toner is not limited to two core-shell layers, but also includes multilayer particles. The purpose of making the particles multilayered is to improve the selective adsorption of catalysts and chemical resistance of the pattern formed by the present liquid developing toner, as well as to improve the thermal properties and electrical properties. Furthermore, the use of multiple layers can also be used to improve toner dispersibility, charging characteristics, and the like.

[Developing/Fixing]
There is no problem if the development method follows the conventional electrophotographic method. This is because, as mentioned above, the basic characteristics of the toner can be made exactly the same as those of the conventional toner. And if the transfer and fixing conditions follow the conventional electrophotographic method, there will be no problem and a high-fidelity finish. However, as far as the inventors have confirmed, when high-definition image quality is required, such as reproducing fine lines of 100 μm or less, the oven heater method seems to be good for fixing. Also, in liquid development, high-definition development can be obtained by reducing the remaining liquid on the substrate as much as possible using a squeeze roller or a squeeze roller as in the conventional method, and then drying with air, including hot air. The fixing temperature depends on the toner composition, but it is possible to configure it to harden and fix at about 100° C. to 120° C., and it is possible to use a PET substrate.

[Preprocessing]
When there is a catalytic metal on the toner surface as described in Patent Document 2, as long as the catalytic metal is exposed on the surface, the catalytic metal is already present and there is no need for a process to attach the catalytic metal. Instead, it can be immersed in an electroless plating solution immediately. However, since the toner of the present invention does not yet have a catalytic metal at the time of completion of fixing, a pretreatment to impart a catalytic metal for electroless plating is necessary. In the present invention, a treatment method is used in which the material is immersed in an aqueous solution of a metal salt such as an aqueous solution of palladium chloride or an aqueous solution of palladium sulfate. The reason why the catalytic metal is adsorbed to the toner is that, as described above, a group having a ligand that incorporates the metal and forms a metal complex is introduced into the shell resin of the toner. Since a mere insulating base material does not have the ability to capture the catalytic metal, the catalytic metal is present only in the toner pattern area. This pretreatment method is a common process especially when electroless plating is performed on metals, and one of the important features of the present invention is that it is the same pretreatment method.
However, if the catalytic metal is adsorbed as ions, depending on the situation, it may be necessary to add a step of metallization by reduction with phosphinic acid, formalin, etc.
Conventionally, when electroless plating is applied to plastics, a two-step process using a tin catalyst and a palladium catalyst (sensitizing-activation method) or a palladium-tin colloidal particle catalyst process using a mixed solution of stannous chloride and palladium chloride (catalyst acceleration method) is used. method) allows the catalytic metal to be attached to the plastic. The reason why tin is used is because it has the property of adhering to plastic, whereas palladium does not have that property. Since tin gets in the way during plating, a treatment process is required to remove it. Furthermore, to put it in an extreme, tin will stick to anything, so it is good for plating the entire surface, but it cannot be used for selective plating where it only sticks to patterns. In recent years, methods using colloidal palladium or colloidal silver as catalysts have been used, but these colloidal materials also tend to adhere to anything, making selective plating difficult. It can be said that this has made patterned plating difficult until now.
In the present invention, the metal adsorbed to the complex resin of the toner is not limited to palladium. Formaldehyde is generally used as a reducing agent in copper plating, but it has been reported that the metals with the highest catalytic activity for formaldehyde oxidation reactions are copper, gold, silver, platinum, nickel, and cobalt, in order. be. There is great potential to use these metal salts as catalyst liquids. Moreover, since there is no need to convert the catalyst into nanometallic material, it is a very cost-effective method.
However, this does not mean that nanometallized catalyst metals cannot be used at all. A system could be established if the resin that colloidizes the nano-metallic catalyst metal has the property of adsorbing only to the functional groups of the toner.

[Electroless plating]
The electroless plating solution, its management, and plating method can be performed as in the past, and there is no special need for it. The difficulties of plating are the same as in the present invention, but the electroless plating method is an established technology and its quality is guaranteed.

[Example]
[Liquid development toner production and plating confirmation]
(Preparation of liquid developing toner)
An example of producing a specific liquid developing toner for realizing the present invention will be described.
A liquid developing toner (S2) for use in the present invention was produced according to the following procedure C1⇒S1⇒S2.
(1) Preparation of C1 liquid Vinyl acetate: 60 parts Lauryl methacrylate: 15 parts Isopar E: 170 parts Add 1 part or more of azobisisobutyronitrile to a four-neck flask, add a stirrer, a reflux condenser, and a nitrogen inlet pipe. and a thermometer, and heated at 80° C. for 3 hours while introducing nitrogen, and then heated at 100° C. for 10 hours to obtain a cloudy polymer dispersion.
Furthermore, it was diluted with Isopar G to prepare a dispersion liquid C1 having a solid content concentration of 30%.
(2) Preparation of S1 liquid C1: 180 parts Glycidyl methacrylate: 3 parts Methyl methacrylate: 13 parts Azobisisobutyronitrile: 0.3 parts Isopar G: Pour 45 parts or more into a four-necked flask and stir. The reactor was equipped with a reflux condenser, a nitrogen inlet tube, and a thermometer, and heated at 80° C. for 5 hours while introducing nitrogen to obtain a cloudy polymer dispersion S1.
(3) Preparation of S2 liquid S1: 180 parts Dimethylaminoethyl methacrylate: 6 parts Methyl methacrylate: 6 parts Azobisisobutyronitrile: 0.2 parts Isopar G: Pour 24 parts or more into a four-necked flask. , a stirrer, a reflux condenser, a nitrogen inlet tube, and a thermometer were installed and heated at 80° C. for 5 hours while introducing nitrogen to obtain a cloudy polymer dispersion S2.
Polymer dispersion liquid S2 (solid content 30 wt%) was diluted with Isopar G to a solid content of 0.1%, and a small amount of charge control material was added to prepare a prototype liquid developer toner T1 used in the present invention. The produced toner exhibits positive charge.

(Preparation of electrostatic patterns for plating verification experiments)
In order to confirm that the liquid developing toner T1 prepared above has the ability to form even fine lines by plating, a static electricity pattern was prepared using the method described in Patent Document 3, which was previously filed by the present inventor. For reference, a simple explanation of the method is shown in FIG.
An epoxy-type photoresist is applied to a conductive plate to a thickness of about 10 μm using a spin coater, dried, and a photomask pattern is exposed and developed to produce an intaglio (10) with a recessed pattern. A 25 μm-thick PET substrate (20) with a conductive back surface is placed on top of the photoresist and uniformly charged to +300 V over the entire surface as a preliminary charge, and then the substrate is brought into close contact with the intaglio (10). Next, a +2500 V pulse is applied to the PET electrode (21) relative to the intaglio electrode (11) for 2 seconds, and the PET substrate (20) is then peeled off to form a negative electrostatic pattern.

(Development and fixing of prototype liquid developer toner)
Since there is no commercially available liquid developer, I decided to develop by hand. Pour the liquid developer toner T1 onto the surface of the PET base material (20) on which the electrostatic pattern has been formed, squeeze the liquid developer toner T1 with a metal plate connected to ground potential while maintaining a gap of about 30 μm, and then air dry. As a result, a toner pattern without fogging was obtained.
The toner does not contain any colorant, and before it is fixed, it is in a particle state, so it reflects diffusely and appears slightly white. However, if you put it in an oven at about 110°C for 3 minutes and fix it, the toner becomes transparent and becomes difficult to see, but it hardens. Closely adhered to the PET base material.

(Pre-plating treatment)
The PET substrate (10) on which the toner was fixed was immersed in a 0.04% palladium chloride solution at 40° C. for 10 minutes as a catalytic metal treatment. It was then washed with water and immersed in a 20% sodium hypophosphite solution for 3 minutes, whereby the palladium was reduced and the pattern became visible as a black raised pattern. It was then washed with water again.

(Electroless nickel plating treatment)
The electroless nickel plating solution was prepared using Okuno Pharmaceutical Co., Ltd.'s chemical nickel SEP-LF according to the manufacturer's specifications, kept at approximately 50°C, and immersed the pre-plated PET substrate (10) for 3 minutes. As a result, nickel appeared on the toner pattern. A clean plated metal pattern was obtained. A photograph of the condition is shown in Figure 2. FIG. 3 is an enlarged photograph of a 20 μm thin line portion.

As described above, a method for producing a high-definition metal pattern using a fully additive method was demonstrated through toner and plating experiments according to the basic concept of the present invention.

[System configuration]
The present invention proposes a means for producing a metal pattern from a pattern using static electricity, and the electrostatic pattern and development are applied to the field of industrial equipment by using a means capable of continuous output, as typified by electrophotography. It shows that you can contribute to Furthermore, in industry, systems that can perform plating pretreatment and electroless plating treatment continuously are already in operation. From this, if the base material is a film, it is easy to construct a system for producing continuous metal patterns using a roll-to-roll method.
As an example, FIG. 4 shows a composition in which a toner pattern is produced on a continuous base film through an electrophotographic device, and FIG. 5 shows a composition in which a toner pattern produced on a continuous base material is continuously plated.
Furthermore, if the method of Patent Document 3 is used to produce electrostatic patterns, thin metal patterns of 3 to 5 μm, which cannot be achieved with current electrophotographic photoreceptors, are no longer a dream, and it is also possible to continuously produce metal mesh touch panels. become.
The system according to the present invention is extremely stable because it is composed of the mature technologies of electrophotography and electroless plating using a special toner, and it is possible to construct a low-cost fully additive system using the present invention. .

Code explanation

10 Intaglio (with electrode)
11 Intaglio electrode 20 PET base material (with electrode)
21 Electrode of PET base material 22 PET film 31 Developing toner for plating 70 Metal plating pattern 100 Electrophotographic device 101 Fixing device 200 Base film roll 201 Base film roll 202 with toner pattern formed Base material with metal plating pattern formed Material film roll 203 Catalytic metal bathtub 204 Washing bathtub 205 Electroless metal plating bathtub 206 Dryer

Claims (7)

a developing step in which charged insulating resin particles called toner are attached to the electrostatic pattern portion formed on the surface of the electrically insulating base material;
a fixing step of fixing the toner on the base material using means for melting or crosslinking the toner with heat or light irradiation or electromagnetic waves on the pattern developed in the developing step ;
a pretreatment step of adsorbing a plating catalyst metal or catalyst metal ions to the toner fixed on the base material;
A metal pattern manufacturing method comprising a metal layer manufacturing step of manufacturing a metal layer by immersing the base material that has undergone the pretreatment step in an electroless plating solution,
A method for producing a metal pattern, wherein the toner includes a resin having a ligand that forms a metal complex as a part of the resin. A pattern portion of an original plate having an electrostatic pattern or a pattern formed of a conductive material is
a developing step in which electrically charged insulating resin particles, called toner, are deposited;
a transfer step of transferring the toner adhered in the developing step onto an electrically insulating substrate;
a fixing step of fixing the transferred toner onto the substrate by using a means for melting or crosslinking the toner by applying heat, light irradiation, or electromagnetic waves ;
a pretreatment step of adsorbing a plating catalyst metal or a plating catalyst metal ion to the toner fixed on the substrate;
A method for producing a metal pattern, comprising a metal layer producing step of producing a metal layer by immersing the base material after the pretreatment step in an electroless plating solution,
The method for producing a metal pattern is characterized in that the toner contains a resin having a ligand for forming a metal complex as a part of the resin constituting the toner. 3. The method for producing a metal pattern according to claim 1, wherein the toner is composed of a core resin and a shell resin covering the core, and a part of the shell resin is a resin having a ligand that forms a metal complex. 4. The method for producing a metal pattern according to claim 1, wherein the toner has resistance to acid or alkali or resistance to both. 5. The method for producing a metal pattern according to claim 1, wherein the surface of the substrate is treated to be water repellent. 6. The method for producing a metal pattern according to claim 1, wherein a resin having a ligand for forming a metal complex, which is a part of the resin constituting the toner, is an amine type or an imidazole type. The method for producing a metal pattern according to any one of claims 1 to 6, wherein the base material is an insulating film used for a touch panel.

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