JP2018103460A - Conductive pattern forming method, conductive pattern forming printing plate and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for forming a conductive pattern, with which breaking of wire of the obtained conductive pattern is infrequent, and with which excellent light transmittance is achieved, and to provide a printing plate for forming the conductive pattern and a production method of the same, with which the conductive pattern with infrequent breaking of wire and with excellent light transmittance can be formed.SOLUTION: A method for forming a conductive pattern includes: a step to prepare a printing plate which has a recessed line formed by cutting on the surface; a step to hold a conductive ink on a recess of the recessed line; a step to transfer the conductive ink on the recess to a substrate; and a step to sinter the conductive ink transferred on the substrate. A production method of a printing plate for forming the conductive pattern includes: a step to prepare the printing plate for forming the conductive pattern, which has the recessed line formed by cutting on the surface and a printing original plate; and a step to form the recessed line on the surface of the printing original plate by cutting.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to a conductive pattern forming method, a conductive pattern forming printing plate, and a manufacturing method thereof.

Conventionally, conductive patterns by printing have been widely used in various fields as various sensors such as pressure sensors and biosensors, printed boards, solar cells, capacitors, electromagnetic wave shields, touch panels, antennas and the like.
Examples of conventional conductive pattern forming methods include the methods described in Patent Documents 1 to 4.
Patent Document 1 discloses a method for forming a fine line pattern having a line width of 1 to 60 μm on one surface of a flexible base material with a conductive paste, which is formed on the surface of a gravure cylinder of a gravure printing machine. A conductive paste is press-fitted into the mold groove of the fine line pattern of the plate with a doctor blade, and viewed from the rotation axis direction of the gravure cylinder, the gravure cylinder at a position of 45 to 180 degrees clockwise or counterclockwise from the upper end. A method for forming a fine line pattern is described in which line contact is made with a transfer material, and the conductive paste is transferred from the gravure plate to the transfer material at the line contact position.

In Patent Document 2, the surface of an ink resin printed with a circuit pattern on a substrate is coated with a colloidal solution in which conductive nanometal powder having an average particle size of 0.1 nm to 50 nm is dispersed, and then the colloidal solution is used. And the ink resin is heated to evaporate the liquid in the colloidal solution, fuse the conductive nanometal powders together, and form a conductive metal film on the surface of the ink resin to be heat-cured. A circuit manufacturing method characterized by the above is described.
In Patent Document 3, a conductive pattern is formed by forming a net-like pattern having an average line width of 50 μm or less made of a resin composition on a transparent substrate by a gravure printing method, and providing a metal layer on the pattern. A method for producing a transparent electromagnetic wave shielding material is described.
Patent Document 4 discloses a method of manufacturing a printed circuit board on an insulating carrier (2), in which a circuit pattern (1) is formed on the carrier using a conductive ink, and then the carrier is plated. And a method characterized in that the conductive ink is added by a gravure printing method.

JP 2010-258381 A JP 2004-172288 A JP 2003-304090 A JP-T-2004-529499

Conventionally, when the conductive pattern is formed by screen printing, the line width is usually 50 to 70 μm and the line width of 50 μm or less is difficult due to the accuracy of finishing the opening width of the opening hole pattern.
Also, when the conductive pattern is formed by letterpress printing (flexographic printing), the plate is soft, so the plate is crushed by printing, and the line width tends to be thick, and the line width is usually 20 to 30 μm, Since the thickness of the ink is thin, there is a problem in that disconnection is likely to occur when a fine line is printed.
When a conductive pattern is formed by lithographic printing, the line width possible at the mass production level is 50 μm or more, and, as with letterpress printing, the thickness of the ink is so thin that it tends to cause disconnection when printing fine lines. Furthermore, since the ink is transferred to the base material via the blanket, there is a problem that unevenness of the printing pattern, increase in line width, disconnection, etc. are likely to occur in response to the change of the blanket state over time. there were.

The problem to be solved by an embodiment of the present invention is to provide a method for forming a conductive pattern that is less in the disconnection of the obtained conductive pattern and excellent in light transmittance.
Another problem to be solved by other embodiments of the present invention is to provide a printing plate for forming a conductive pattern that can form a conductive pattern with less disconnection and excellent light transmittance, and a method for manufacturing the same. It is.

Means for solving the above problems include the following aspects.
<1> A step of preparing a printing plate having a concave line formed by cutting on the surface, a step of holding conductive ink in the concave portion of the concave line, and a transfer of the conductive ink held in the concave portion to the substrate A conductive pattern forming method including a step and a step of sintering the conductive ink transferred to the substrate.
<2> The conductive pattern forming method according to <1>, wherein the concave line is a concave line formed by cutting using a cutting tool.
<3> The conductive pattern forming method according to <2>, wherein the cutting tool does not vibrate at a constant frequency in a direction perpendicular to a surface to be cut of the printing plate during cutting.
<4> The conductive pattern forming method according to any one of <1> to <3>, wherein the printing plate is a metal plate.
<5> The conductive pattern forming method according to <4>, wherein the metal plate is a metal roll.
<6> The conductive pattern forming method according to any one of <1> to <5>, wherein the concave line includes a concave line having a line width of 10 μm or less.
<7> The method according to any one of the above items <1> to <6>, wherein the holding step, the transferring step, and the sintering step are performed during a period from one feeding of the substrate to winding. The conductive pattern forming method.
<8> The conductive pattern forming method according to any one of <1> to <7>, wherein the sintering is performed by at least one selected from the group consisting of heat and light.
<9> The conductive pattern forming method according to any one of <1> to <8>, wherein the sintering is performed by heating at a temperature of 80 ° C. to 200 ° C. in the step of sintering.
<10> The conductive pattern forming method according to any one of <1> to <9>, wherein the volume resistance value of the conductive ink is 20 μΩ · cm or less.
<11> The conductive pattern forming method according to any one of <1> to <10>, wherein the conductive ink is a conductive ink containing silver nanoparticles.
<12> A printing plate for forming a conductive pattern having a concave line formed by cutting on its surface.
<13> A method for producing a printing plate for forming a conductive pattern, comprising a step of preparing a printing plate precursor and a step of forming a concave line on the surface of the printing plate precursor by cutting.

According to one embodiment of the present invention, it is possible to provide a conductive pattern forming method that is less in disconnection of the obtained conductive pattern and excellent in light transmittance.
In addition, according to another embodiment of the present invention, it is possible to provide a printing plate for forming a conductive pattern and a method for manufacturing the same, which can form a conductive pattern with less disconnection and excellent light transmittance.

It is a cross-sectional enlarged schematic diagram which shows an example of the cross-sectional shape of the concave line vicinity part in the line width direction of the concave line formed in the surface of the printing plate in the conductive pattern formation method which concerns on this embodiment. It is a cross-sectional enlarged schematic diagram which shows another example of the cross-sectional shape of the concave line vicinity part in the line width direction of the concave line formed in the surface of the printing plate in the conductive pattern formation method which concerns on this embodiment. It is a schematic diagram which shows an example of the flat printing plate in the conductive pattern formation method which concerns on this embodiment. FIG. 4 is a partial schematic enlarged view including a concave line 106 in an elliptical portion 108 shown in FIG. 3.

Hereinafter, the contents of the present disclosure will be described in detail. The description of the constituent elements described below may be made based on typical embodiments of the present disclosure, but the present disclosure is not limited to such embodiments.
In the specification of the present application, “to” indicating a numerical range is used in a sense including numerical values described before and after the numerical value as a lower limit value and an upper limit value.
Moreover, in the description of the group (atomic group) in this specification, the description which does not describe substitution and non-substitution includes what does not have a substituent and what has a substituent. For example, the “alkyl group” includes not only an alkyl group having no substituent (unsubstituted alkyl group) but also an alkyl group having a substituent (substituted alkyl group).
In the present disclosure, “mass%” and “wt%” are synonymous, and “part by mass” and “part by weight” are synonymous.
Furthermore, in the present disclosure, a combination of two or more preferred embodiments is a more preferred embodiment.
Hereinafter, the present disclosure will be described in detail.

(Conductive pattern forming method)
The conductive pattern forming method according to the present disclosure includes a step of preparing a printing plate having a concave line formed by cutting on a surface thereof, a step of holding conductive ink in a concave portion of the concave line, and a conductivity held in the concave portion. A step of transferring the conductive ink to the substrate, and a step of sintering the conductive ink transferred to the substrate.

As a result of intensive studies by the present inventors, it has been found that, by adopting the above-described configuration, a conductive pattern forming method with less light disconnection and excellent light transmittance can be provided.
Although the mechanism of the excellent effect by this is not clear, it is estimated as follows.
Because it is an intaglio, the amount of ink transferred is larger than that of letterpress and lithographic plates. Therefore, it is estimated that disconnection is less likely to occur when printing fine patterns, the resulting conductive pattern has less disconnection, and is excellent in light transmission. ing.
In addition, the indentation of the intaglio plate is formed by an electronic engraving (for example, paragraphs 0081 of JP-T-2015-506289 and columns 7 to 8 of JP-B 62-17540). Engraving), and by forming by cutting rather than by laser plate making using a resist, a concave line with a narrow line width can be easily formed with less disconnection, It is presumed that the obtained conductive pattern is also excellent in light transmittance. “Cutting” in the present disclosure is different from the above-described electronic engraving for engraving the cells, and a processing tool (for example, a bite) described later is brought into contact with the surface of the printing plate precursor to form a desired concave surface of the printing plate precursor. It is a process to scrape off. Note that the printing plate precursor in the present disclosure refers to an uncut substrate. For example, in a direction perpendicular to the surface of the printing plate precursor, the processing tool is preferably processed as a concave line shape without being processed into a cell shape by vibrating at a constant frequency. In the concave portion formed by the engraving described above, the line width of the obtained conductive pattern is large and the light transmittance is inferior, and the shape of the concave portion of the obtained conductive pattern is not stable, resulting in increased disconnection.
Further, in the above-described cutting, the shape of the portion to be cut in contact with the processing tool is preferably at least twice as long as the line width of the recess, and more than 5 times as long as the line width of the recess. More preferably. The upper limit is not particularly limited, but is preferably 10,000 times or less.

<Process to prepare>
The conductive pattern forming method according to the present disclosure includes a step of preparing a printing plate having a concave line formed on a surface thereof by cutting.
The concave line on the surface of the printing plate used in the present disclosure is formed by cutting.
The printing plate used in the present disclosure is not particularly limited as long as it has a cuttable surface, but it is preferable to have a metal layer on the surface from the viewpoint of machinability, printability, and durability. More preferably, it has an alloy, nickel or nickel alloy layer, more preferably has a copper or nickel layer on its surface, and particularly preferably has a copper or nickel plating layer on its surface.
Further, from the viewpoint of durability, the copper or nickel (plating) layer has a surface hardened layer of either a chromium plating layer or a diamond-like carbon (DLC) layer on at least a part of its surface. It is preferable to have a chromium plating layer.

The thickness of the metal layer is not particularly limited, but is preferably 20 μm or more and 1,000 μm or less, more preferably 30 μm or more and 300 μm or less, and 40 μm from the viewpoints of machinability, printability, and durability. The thickness is particularly preferably 200 μm or more.
The thickness of the surface hardened layer is preferably from 0.1 μm to 20 μm, more preferably from 0.1 μm to 10 μm, and more preferably from 0.2 μm to 5 μm from the viewpoint of durability. It is particularly preferred.

The form of the printing plate used in the present disclosure may be a flat surface or a roll. Moreover, it is good also as a roll, after cutting a flat printing plate precursor.
The material of the flat plate precursor used in the present invention is not particularly limited, but the flat plate precursor is preferably a metal plate, a group consisting of copper, copper alloy, nickel and nickel alloy. More preferably, the plate is made of a material selected from.
There is no restriction | limiting in particular in the material of the core material in the printing roll used for this indication, A well-known gravure printing roll can be used, A metal roll is mentioned preferably from a viewpoint of cost or durability.
Moreover, it is preferable that the core material of the printing roll is iron or aluminum from the viewpoint of cost and durability.
The width, outer diameter, inner diameter and the like of the printing roll are not particularly limited and can be appropriately set as desired.

The shape of the concave line is not particularly limited, but the cross-sectional shape of the concave line in the line width direction is an inverted triangle, a rectangle, or an inverted trapezoid from the viewpoint of suppressing disconnection of the obtained conductive pattern and light transmittance. Is more preferable, an inverted triangle or a rectangle is more preferable, and an inverted triangle is particularly preferable. Moreover, the tip of the inverted triangle may be rounded.
Moreover, the concave line formed in the said printing plate can be formed not only in the concave line on a straight line but in arbitrary pattern shapes.
Further, the number of the concave lines is not particularly limited, and a desired number can be formed.
Further, the pitch interval of the concave lines is not particularly limited, and the concave lines may be formed at a desired interval, but is preferably 5 μm to 2,000 μm, and more preferably 10 μm to 1,000 μm. .

The concave line preferably includes a concave line having a line width of 10 μm or less, and more preferably includes a concave line having a line width of 0.3 μm or more and 10 μm or less, from the viewpoint of light transmittance of the obtained conductive pattern. It is more preferable to include a concave line having a line width of 0.4 μm to 8 μm, and it is particularly preferable to include a line width of 0.5 μm to 6 μm.
The depth of the concave line is preferably 0.2 μm or more and 40 μm or less, more preferably 0.3 μm or more and 30 μm, from the viewpoint of suppression of disconnection of the obtained conductive pattern and light transmittance. More preferably, it is 4 μm or more and 25 μm or less, and particularly preferably 0.5 μm or more and 20 μm or less.

  The aspect ratio (depth / line width) between the line width and the depth of the concave line is preferably 0.3 to 7, more preferably 0.5 to 5, and 0.8 to 3. It is particularly preferred. Within the above range, the amount of conductive ink retained is sufficient, the amount transferred to the substrate is sufficient, the occurrence of disconnection is suppressed, and the conductive ink is transferred to the substrate. In this case, it is possible to prevent the conductive ink from remaining on the surface, and cleaning after printing is easy.

FIG. 1 is an enlarged schematic cross-sectional view showing an example of a cross-sectional shape of a portion near a concave line in the line width direction of the concave line formed on the surface of the printing plate in the conductive pattern forming method according to the present embodiment.
The concave line 10 formed on the surface of the printing plate shown in FIG. 1 has an inverted triangle cross-sectional shape in the line width direction of the concave line, and is formed by cutting a metal layer 12 such as a copper or nickel layer.
Moreover, in the concave line 10 shown in FIG. 1, the depth 14 and the line width 16 are shown in FIG.
In addition, the line width of the concave line in the present disclosure is a length (width) in a direction perpendicular to the line direction of the concave line on the surface of the printing plate as shown in FIG. 1, and the line width direction of the concave line is In the surface direction of the printing plate, the direction is perpendicular to the line direction of the concave line. Further, the depth of the concave line in the present disclosure is a cutting depth, and represents a distance from a point in the concave portion farthest from a line connecting two end points in the line width direction of the concave line on the printing plate surface. 1 corresponds to the depth 14 in the cross-sectional shape of the concave line in the line width direction.

FIG. 2 is an enlarged schematic cross-sectional view showing another example of the cross-sectional shape of the portion near the concave line in the line width direction of the concave line formed on the surface of the printing plate in the conductive pattern forming method according to the present embodiment. is there.
The surface of the printing plate shown in FIG. 2 has a hardened surface layer 18, and the concave line 10 formed on the surface of the printing plate has an inverted triangular cross-sectional shape in the line width direction. A metal layer 12 such as a copper or nickel layer is cut and formed, and a surface hardened layer 18 is formed on the surface thereof.
Moreover, in the concave line 10 shown in FIG. 2, the depth 14 and the line width 16 are shown in FIG.

Furthermore, FIG. 3 is a schematic diagram showing an example of a flat plate-like printing plate in the conductive pattern forming method according to the present embodiment.
The printing plate 100 shown in FIG. 3 is made of a metal plate 102 and has a chromium plating layer (not shown) having a thickness of 1 μm as a hardened surface on the surface thereof. The metal plate 102 has a width of 170 mm, a length of 400 mm, and a thickness of 2 mm. The metal plate 102 is made of copper. Further, the concave line 106 repeatedly formed on the cutting portion 104 on the surface of the printing plate has an inverted triangular cross-sectional shape in the line width direction. The cutting portion 104 is a central portion having a width of 35 mm from the end of the metal plate 102 in the vertical and horizontal directions. In the cutting portion 104, the concave line 106 is formed not only on the two concave lines shown in FIG.
4 is a partial schematic enlarged view including the concave line 106 in the elliptical portion 108 shown in FIG.
Line width ^{L 1} of each凹線106 is 5 [mu] m, the distance ^{L s} between the two凹線106 is 100 [mu] m. When observed from the surface of the metal plate 102, each concave line 106 is formed in a wavy shape, and the inner diameter of one hemisphere as a part of the wave in the wavy shape of the concave line is 10 mm. The radius (the distance from the center of the hemisphere to the contact with the concave line) is 5 mm.

As a method for forming a concave line on the surface of the printing plate by cutting, a method using a cutting tool is preferably exemplified.
Examples of the bite include diamond (single crystal), diamond sintered body (polycrystal), cubic boron nitride (cBN) sintered body, ceramics, cermet, cemented carbide, high speed steel (high speed), and coated. However, single crystal diamond is preferable from the viewpoint of processing accuracy.
In addition, the cutting tool preferably has a V-shaped cutting tool, that is, the cutting surface of the cutting tool (the surface contacting the workpiece) is preferably V-shaped, and the V-shaped angle is More preferably, it is 90 degrees or less, the V-shaped angle is more preferably 75 degrees or less, and the V-shaped angle is particularly preferably 15 degrees or more and 65 degrees or less.
Furthermore, it is preferable that the cutting tool does not vibrate at a constant frequency in a direction perpendicular to the surface to be cut of the printing plate during cutting. In a direction perpendicular to the surface to be cut of the printing plate, such as engraving, in a direction perpendicular to the surface to be cut of the printing plate during cutting, as compared with an aspect in which cutting is performed by vibrating a cutting tool at a constant frequency. In this case, the cross-sectional shape of the concave line due to the cutting is stabilized, the disconnection of the obtained conductive pattern is further suppressed, and the concave line can be made a finer wire. The light transmittance of the pattern is more excellent.

<Holding process>
The conductive pattern forming method according to the present disclosure includes a step of holding conductive ink in the concave portion of the concave line.
The amount of conductive ink retained in the concave portion is not particularly limited as long as it can sufficiently form a conductive pattern in the transfer described later.
There is no restriction | limiting in particular as a method of hold | maintaining the conductive ink to the said recessed part, It can use by a well-known method. Specifically, for example, there is a method in which the surface of the printing plate and the conductive ink are brought into contact with each other and excess conductive ink other than the recesses is removed by a removing means such as a doctor blade.

The conductive ink used in the present disclosure may be a thermal sintering type, a photosintering type, or a thermal and photosintering type.
The volume resistance value of the conductive ink is preferably 20 μΩ · cm or less, more preferably 15 μΩ · cm or less, and more preferably 10 μΩ · cm or less, from the viewpoints of conductivity and light transmittance. It is particularly preferred. The lower limit value is not particularly limited, but is preferably 10 ⁻⁵ μΩ · cm or more.

Moreover, although the conductive ink used for this indication can use a conductive paste and a conductive nano ink, the conductive nano ink containing a metal particle is preferable from the point of resistance value.
As the material of the metal particles used in the conductive ink, copper, silver, nickel, aluminum, gold, platinum, palladium, and an alloy of two or more of these can be used, but the resistance value, cost, Silver, copper or an alloy thereof is preferable from the viewpoint of sintering temperature and the like, and silver is particularly preferable from the viewpoint of sintering temperature and oxidation suppression.
The particle diameter of the metal particles is preferably 0.1 nm to 50 nm, more preferably 1 nm to 20 nm, from the viewpoint of stability and fusion temperature.
Among these, the conductive ink is particularly preferably a conductive ink containing silver nanoparticles from the viewpoint of low resistance.
As the solvent contained in the conductive ink, water and an organic solvent can be used.
As the organic solvent, hydrocarbons such as toluene, dodecane, tetradecane, cyclododecene, n-heptane and n-undecane, and alcohols such as ethanol and isopropyl alcohol are preferable.
The content of the metal particles in the conductive ink is preferably 10 to 95% by mass, and preferably 30 to 80% by mass from the viewpoints of metal film formation during sintering and dispersion stability. More preferred.

Examples of the conductive paste include those containing metal particles and a binder polymer.
The metal particles in the conductive paste are preferably those described above.
There is no restriction | limiting in particular in the binder polymer in the said electrically conductive paste, A well-known binder polymer can be used.
Examples of the binder polymer include thermoplastic resins such as polyester resin, (meth) acrylic resin, polyethylene resin, polystyrene resin, and polyamide resin. Moreover, thermosetting resins, such as an epoxy resin, an amino resin, a polyimide resin, and a (meth) acrylic resin, may be sufficient.
Moreover, the said electrically conductive paste can perform viscosity adjustment with the addition amount of a solvent, etc.

<Transfer process>
The conductive pattern forming method according to the present disclosure includes a step of transferring the conductive ink held in the concave portion to a base material.
There is no restriction | limiting in particular as the transfer method in the said process to transfer, The method of transferring by making the printing plate which has a recessed part with which the electroconductive ink was hold | maintained by making a base material contact with pressure is mentioned suitably.

Examples of the base material used in the present disclosure include polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyolefin resins such as polyethylene and polypropylene, cyclic polyolefin resins, and cellulose derivative resins (carboxymethyl cellulose, hydroxyalkyl cellulose, Cellulose acetate, etc.), acrylic resin, epoxy resin, fluororesin, silicone resin, polycarbonate resin, diacetate resin, triacetate resin, polyarylate resin, polyvinyl chloride, polysulfone resin, polyethersulfone resin, polyimide resin, polyamide resin, polyurethane Examples thereof include resins. Among these, from the viewpoint of cost and optical properties, a polyester resin, a cyclic polyolefin resin, or a cellulose derivative resin is preferable.
There is no restriction | limiting in particular in the thickness and shape of the said base material, What is necessary is just to select suitably as needed.
The base material is preferably a roll base material.
Furthermore, the base material may be subjected to surface treatment such as corona treatment.

The conductive pattern forming method according to the present disclosure may include a step of drying the conductive ink transferred to the substrate, if necessary.
In addition, the conductive pattern forming method according to the present disclosure may be performed together with sintering in the sintering step described later to dry the conductive ink.
The drying method is not particularly limited, and may be heat drying, air drying, or a combination thereof.
There is no restriction | limiting in particular also about drying temperature and drying time, According to the conductive ink to be used etc., it can select suitably.

<Sintering process>
The conductive pattern forming method according to the present disclosure includes a step of sintering the conductive ink transferred to the substrate.
The sintering in the sintering step is preferably performed by at least one selected from the group consisting of heat and light from the viewpoint of conductivity and manufacturing efficiency.
In the case of performing thermal sintering, the heating temperature in the sintering step is preferably 80 ° C. to 200 ° C., more preferably 100 ° C. to 150 ° C. from the viewpoints of heat resistance of the base material and resistance value. .
Moreover, when performing heat sintering, it is preferable that the heating time in the said process to sinter is 0.5 minute-30 minutes from a viewpoint of manufacturing efficiency and resistance value, and it is 1 minute-20 minutes. More preferably, it is particularly preferably 2 to 10 minutes.

In the case of photosintering, the type of light to be irradiated in the sintering step is not particularly limited as long as the conductive ink to be used can be sintered, but is preferably light containing ultraviolet rays.
Also it, when performing light sintering, irradiation energy of the irradiation in the process of the ^sintering, it is 1J / cm ² ~10J / cm 2 is ^{preferably, 2J / cm 2 ~6J / cm} 2 it is more ^preferable, and particularly preferably ^{3J / cm 2 ~5J / cm 2} .
Furthermore, in the case of photosintering, the light irradiation time in the sintering step depends on the energy of the light to be irradiated and is not particularly limited. Also good. When performing flash exposure, the light irradiation time is preferably 0.1 ms (milliseconds) to 10 ms, more preferably 0.2 ms to 5 ms, and particularly preferably 0.5 ms to 4 ms. .

<Printing device>
The printing apparatus used in the conductive pattern forming method according to the present disclosure is not particularly limited, and a known gravure printing apparatus can be used. For example, a sheet-fed or rotary gravure printing machine, or a gravure type printing apparatus can be used. A coater can be suitably used.
These printing machines or coaters are (1) a base feed section, (2) a conductive ink is supplied to the plate, and the non-image portion of the plate is scraped off with a doctor blade, and the ink held in the recess (image portion) is removed. It is preferable to include a patterning unit to be transferred to the substrate, (3) a drying unit, and (4) a winding unit.
In the case of thermal sintering, (3) drying of the organic solvent contained in the conductive ink and thermal sintering can be simultaneously performed in the drying section. In addition, if there is an exposed part between (3) the drying part and (4) the take-up part, (3) the organic solvent contained in the conductive ink is dried in the drying part, and the exposed part is photo-sintered. It is preferable at the point which can do. Furthermore, there may be a substrate surface treatment part such as a corona treatment for ensuring the adhesion between the conductive ink and the substrate, between (1) the substrate delivery part and (2) the patterning part, (3) Between the drying section and (4) the winding section, there may be a laminate section for attaching another substrate.

  Further, in the conductive pattern forming method according to the present disclosure, from the viewpoint of manufacturing efficiency, the holding step, the transferring step, and the sintering step are performed during a period from one feeding of the substrate to winding. It is preferable to carry out. “In-line” in the present disclosure indicates that the base material feeding portion to the base material winding portion are continuous. Therefore, when performing thermal sintering in the drying section, it is preferable that the drying line length of the drying section is secured to such an extent that the conductive ink is sufficiently sintered.

(Printing plate for conductive pattern formation)
The conductive pattern forming printing plate according to the present disclosure has a concave line formed by cutting on the surface.
In addition, the conductive pattern forming printing plate according to the present disclosure is preferably manufactured by a method for manufacturing a conductive pattern forming printing plate according to the present disclosure described later.
The printing plate for forming a conductive pattern according to the present disclosure is synonymous with the printing plate in the above-described method for forming a conductive pattern according to the present disclosure, and a preferable aspect thereof is also the same.

(Method for producing printing plate for forming conductive pattern)
The manufacturing method of the conductive pattern forming printing plate according to the present disclosure includes a step of preparing a printing plate precursor and a step of forming a concave line on the surface of the printing plate precursor by cutting.
As the printing plate precursor in the step of preparing the printing plate precursor, one having a copper or nickel layer formed on the surface of a flat plate or roll can be suitably used, and the preferred embodiment is also the same.
The copper or nickel layer in the method for producing a printing plate for forming a conductive pattern according to the present disclosure is preferably the copper or nickel layer described above in the method for forming a conductive pattern according to the present disclosure, and a preferable aspect is also the same.

In the step of forming the concave line, it is preferable to cut using a cutting tool, and it is more preferable to cut using a V-shaped cutting tool at the tip.
As the cutting tool, the above-described cutting tool is preferably used in the conductive pattern forming method according to the present disclosure, and a preferable aspect thereof is also the same.
Moreover, when forming one concave line using a bite in the process of forming the said concave line, it is preferable to cut a bite without vibrating at the time of cutting from a viewpoint of wire breakage suppression and line width variation suppression.

Moreover, the manufacturing method of the printing plate for conductive pattern formation which concerns on this indication is a chromium plating layer or at least one part of the said surface which formed the concave line after the process of forming the said concave line from a viewpoint of durability. Preferably, the method includes a step of forming any of the DLC layers, and more preferably includes a step of forming a chromium plating layer on at least a part of the surface on which the concave line is formed after the step of forming the concave line. .
As for the chromium plating layer or DLC layer in the manufacturing method of the conductive pattern forming printing plate according to the present disclosure, the chromium plating layer or the DLC layer described above in the conductive pattern forming method according to the present disclosure is preferably exemplified, and a preferable aspect is also provided. It is the same.

  Hereinafter, the present disclosure will be described in detail by way of examples, but the present disclosure is not limited thereto. In this example, “part” means “part by mass” unless otherwise specified.

  Details of various components used in Examples and Comparative Examples are shown below.

Example 1
<Plate making conditions>
Electro copper plating was performed on the surface of an iron roll having a width of 1,000 mm, an outer diameter of 200 mm, and an inner diameter of 100 mm (plating thickness: 80 μm).
On the surface, cutting is performed with a V-shaped diamond cutting tool having an angle of 60 ° (cutting machine: ULR-628B manufactured by Toshiba Machine Co., Ltd.), and L (line) / S (space) = 5 μm / 300 μm concave. A line was formed in the circumferential direction (35 mm from both ends of the roll was a blank part where no concave line was formed).
Thereafter, in order to impart surface hardness, electrochrome plating was performed (plating thickness: 1 μm).

<Printing conditions>
Printing was performed with a rotary gravure printing machine under the following conditions.
Base material: Cosmo Shine A4300 (polyethylene terephthalate film, thickness 38 μm) manufactured by Toyobo Co., Ltd.
Conductive ink: Water-based silver nano ink manufactured by DOWA Electronics Co., Ltd. (volume resistance value after 120 ° C./30 seconds: 4 μΩ · cm)
・ Dry length: 25m
-Thermal sintering conditions (drying part temperature): 120 ° C
・ Printing speed: 5m / min (sintering time 5min)

(Example 2)
Example 1 except that organic solvent silver nano ink (organic solvent silver nano ink, organic solvent: alcohol compound containing ethanol, volume resistance: 4 μΩ · cm) manufactured by DOWA Electronics Co., Ltd. was used as the conductive ink. Thus, plate making and printing were performed.

(Example 3)
Plate making and printing were performed in the same manner as in Example 1 except that the plate making conditions were the same as in Example 1 and the printing conditions were as follows.

<Printing conditions>
Printing was performed with a rotary gravure printing machine under the following conditions.
-Base material: Kapton 200EN manufactured by Toray DuPont Co., Ltd. (polyimide film, thickness 50 μm)
-Conductive ink: Photo-sintered copper nano ink CJ-0104 manufactured by Ishihara Yakuhin Co., Ltd. (volume resistance value: 6 [mu] [Omega] .cm)
・ Dry length: 25m
-Drying part temperature: 80 ° C
Photo-sintering conditions: Using a flash irradiation apparatus (UX-A3091EM manufactured by Ebara Research Laboratory Co., Ltd.) equipped with a xenon lamp, light irradiation was performed at an energy of 4 J / cm ² for 2 ms.
・ Printing speed: 5m / min

Example 4
Plate making and printing were carried out in the same manner as in Example 1 except that DOTITE XA-3609 (silver paste, volume resistance value: 30 μΩ · cm) manufactured by Fujikura Kasei Co., Ltd. was used as the conductive ink.

(Example 5)
Plate making and printing were performed in the same manner as in Example 1 except that the plate making conditions were changed as follows.

<Plate making conditions>
Using a rectangular diamond cutting tool with a width of 3 μm, the insertion depth is controlled so that the aspect ratio is 5, and cutting is performed (Cutting machine: ULR-628B manufactured by Toshiba Machine Co., Ltd.), L (Line) A concave line of / S (space) = 3 μm / 300 μm was formed in the circumferential direction (35 mm from both ends of the roll was a blank portion where no concave line was formed).
Other plate making conditions were the same as in Example 1.

(Example 6)
Plate making and printing were performed in the same manner as in Example 1 except that the plate making conditions were changed as follows.

<Plate making conditions>
Using a rectangular diamond cutting tool with a width of 1 μm, the insertion depth is controlled so that the aspect ratio is 3, and cutting is performed (cutting machine: ULR-628B manufactured by Toshiba Machine Co., Ltd.), L (line) A concave line of / S (space) = 1 μm / 300 μm was formed in the circumferential direction (35 mm from both ends of the roll was a blank portion where no concave line was formed).
Other plate making conditions were the same as in Example 1.

(Example 7)
Plate making and printing were performed in the same manner as in Example 1 except that the plate making conditions were changed as follows.

<Plate making conditions>
Using a rectangular diamond cutting tool having a width of 0.5 μm, the insertion depth was controlled so that the aspect ratio was 3, and cutting was performed (cutting machine: ULR-628B manufactured by Toshiba Machine Co., Ltd.), L ( Line) / S (space) = 0.5 μm / 300 μm concave line was formed in the circumferential direction (35 mm from both ends of the roll was a blank part where no concave line was formed).
Other plate making conditions were the same as in Example 1.

(Example 8)
Plate making and printing were performed in the same manner as in Example 1 except that the plate making conditions were changed as follows.

<Plate making conditions>
Cutting was performed using a V-shaped diamond cutting tool having an angle of 40 ° (cutting machine: ULR-628B manufactured by Toshiba Machine Co., Ltd.), and a concave line of L (line) / S (space) = 5 μm / 300 μm was formed. It was formed in the circumferential direction (35 mm from both ends of the roll was a blank portion not forming a concave line). Thereafter, in order to impart surface hardness, electrochrome plating was performed (plating thickness: 1 μm).

Example 9
Plate making and printing were performed in the same manner as in Example 1 except that the plate making conditions were changed as follows.

<Plate making conditions>
Cutting is performed using a V-shaped diamond cutting tool with an angle of 20 ° (cutting machine: ULR-628B manufactured by Toshiba Machine Co., Ltd.), and a concave line of L (line) / S (space) = 5 μm / 300 μm is formed. It was formed in the circumferential direction (35 mm from both ends of the roll was a blank portion not forming a concave line). Thereafter, in order to impart surface hardness, electrochrome plating was performed (plating thickness: 1 μm).

(Example 10)
A copper sheet having a width of 170 mm, a length of 400 mm and a thickness of 2 mm was cut with a V-shaped diamond cutting tool having an angle of 60 °, and as shown in FIG. 3, L (line) / S (space) = 5 μm / 100 μm A curved concave line was formed on the plane. In addition, 35 mm from 4 sides of the sheet | seat was made into the blank part which does not form a concave line. Thereafter, in order to impart surface hardness, electrochrome plating was performed (plating thickness: 1 μm).

<Printing conditions>
Printing was performed with a sheet-fed gravure printing machine under the following conditions.
Base material: Cosmo Shine A4300 (polyethylene terephthalate film, thickness 38 μm) manufactured by Toyobo Co., Ltd.
Conductive ink: Water-based silver nano ink manufactured by DOWA Electronics Co., Ltd. (volume resistance value after 120 ° C./30 seconds: 4 μΩ · cm)
After printing, thermal sintering was performed at 120 ° C. for 5 minutes.

(Example 11)
A nickel-phosphorous sheet having a width of 1,000 mm, a length of 640 mm, and a thickness of 200 μm is cut with a V-shaped diamond cutting tool having an angle of 60 °, and a linear shape of L (line) / S (space) = 5 μm / 300 μm. The concave line was formed on a plane. In addition, 35 mm from 4 sides of the sheet | seat was made into the blank part which does not form a concave line. This sheet was wound around an iron roll, and the edges were welded and polished so that there was no step difference in the joints, thereby producing a printing plate.

<Printing conditions>
Printing was performed under the same conditions as in Example 1.

(Comparative Example 1)
Plate making and printing were performed in the same manner as in Example 1 except that the plate making conditions were changed as follows.

<Plate making conditions>
Electro copper plating was performed on the surface of an iron roll having a width of 1,000 mm, an outer diameter of 200 mm, and an inner diameter of 100 mm (plating thickness: 80 μm).
On the surface, a positive photosensitive solution TSER-2104 (manufactured by Sink Laboratory Co., Ltd.) was applied at a thickness of 3.5 μm and dried at 23 ° C. for 45 minutes to form a resist layer.
Next, using a laser exposure apparatus Laser-Stream-FX-1300 (manufactured by Sink Laboratory Co., Ltd.), exposure was performed at an exposure power of 230 mJ / cm ² and a cylinder rotation speed of 200 rpm (rotation / min). In the image pattern, L (line width) is 4 μm, which is the limit of the apparatus, and L (line) / S (space) = 4 μm / 300 μm concave line (35 mm from both ends of the roll is a blank part that does not form a concave line) ).
After the exposure, rotary immersion development was performed at 25 ° C. for 80 seconds using a TLD developer (manufactured by Sink Laboratories).
After the development, the cupric chloride aqueous solution was sprayed with a spray etching apparatus, and the copper was etched at 37 ° C. so that the etching depth was about 4.3 μm, which is substantially the same as that in Example 1. Then, after washing with water and drying, the resist layer in the unexposed area was peeled off to obtain a roll whose entire surface was copper.
Thereafter, in order to impart surface hardness, electrochrome plating was performed (plating thickness 1 μm) to obtain a printing plate.

(Comparative Example 2)
Plate making and printing were performed in the same manner as in Example 1 except that the plate making conditions were changed as follows.

<Plate making conditions>
A resist composition was prepared as follows.
After mixing 40 parts of nitrocellulose varnish, 10 parts of carbon black (Raven 780 Ultra Powder made by Columbian Chemical Co., Ltd.) and 5 parts of ethyl acetate with a disper, they were kneaded with an Eiger mill to prepare a mill base. Thereto was added 6 parts of a polyester resin varnish, 4 parts of castor oil as a plasticizer, and 35 parts of ethyl acetate / toluene / isopropyl alcohol (mixing ratio: 40/40/20) as a diluent solvent to obtain a resist composition.
In the resist composition, Zahn Cup No. 3 was added for 15 seconds to obtain a coating solution.
Electro copper plating was performed on the surface of an iron roll having a width of 1,000 mm, an outer diameter of 200 mm, and an inner diameter of 100 mm (plating thickness: 80 μm).
The coating solution was applied to the surface and dried at 23 ° C. for 45 minutes. The resist film thickness after drying was 3 μm.
Subsequently, the resist layer was ablated by irradiating with a Nd: YAG laser having a wavelength of 1064 nm using a laser exposure apparatus Digilas (manufactured by Schepers). In the image pattern, L (line width) is 4 μm, which is the limit of the apparatus, and L (line) / S (space) = 4 μm / 300 μm concave line (35 mm from both ends of the roll is a blank part that does not form a concave line) ).
After the exposure, the cupric chloride aqueous solution was sprayed with a spray etching apparatus, and the copper was etched at 37 ° C. so that the etching depth was about 4.3 μm, which is substantially the same as that in Example 1. Then, it washed with water and dried.
The resist layer of the non-ablation part was peeled off using the diluting solvent used in the preparation of the resist composition to obtain a roll whose entire surface was copper.
Thereafter, in order to impart surface hardness, electrochrome plating was performed (plating thickness 1 μm) to obtain a printing plate.

(Comparative Example 3)
<Plate making conditions>
Electro copper plating was performed on the surface of an iron roll having a width of 1,000 mm, an outer diameter of 200 mm, and an inner diameter of 100 mm (plating thickness: 80 μm).
On the surface, engraving was performed with a V-shaped diamond stylus having an angle of 130 ° (engraving machine: Helio Klischograph K500, manufactured by Helgravia Japan Co., Ltd.). 35 mm from both ends of the roll was a blank portion where no image was formed.
However, even the minimum point (2% halftone dot portion) is 12 μm wide and the points are discrete, and could not be recognized as a line. Therefore, printing could not be performed and the sheet resistance value could not be measured.

(Comparative Example 4)
Plate making and printing were performed in the same manner as in Example 1 except that the plate making conditions were changed as follows.

<Plate making conditions>
Electro copper plating was performed on the surface of an iron roll having a width of 1,000 mm, an outer diameter of 200 mm, and an inner diameter of 100 mm (plating thickness: 80 μm).
On the surface, a positive photosensitive solution TSER-2104 (manufactured by Sink Laboratory Co., Ltd.) was applied at a thickness of 3.5 μm and dried at 23 ° C. for 45 minutes to form a resist layer.
Next, using a laser exposure apparatus Laser-Stream-FX-1300 (manufactured by Sink Laboratory Co., Ltd.), exposure was performed at an exposure power of 230 mJ / cm ² and a cylinder rotation speed of 200 rpm. In the image pattern, L (line width) is 4 μm, which is the limit of the apparatus, and L (line) / S (space) = 4 μm / 300 μm concave line (35 mm from both ends of the roll is a blank part that does not form a concave line) ).
After the exposure, rotary immersion development was performed at 25 ° C. for 80 seconds using a TLD developer (manufactured by Sink Laboratories).
After development, the cupric chloride aqueous solution was sprayed with a spray-type etching apparatus, and the copper was etched at 37 ° C. so that the width of the recess after etching was about 5 μm. Then, after washing with water and drying, the resist layer in the unexposed area was peeled off to obtain a roll whose entire surface was copper. The recess depth at this time was 0.5 μm.
Thereafter, in order to impart surface hardness, electrochrome plating was performed (plating thickness 1 μm) to obtain a printing plate.

(Comparative Example 5)
Plate making and printing were performed in the same manner as in Example 1 except that the plate making conditions were changed as follows.

<Plate making conditions>
A resist composition was prepared as follows. After mixing 40 parts of nitrocellulose varnish, 10 parts of carbon black (Raven 780 Ultra Powder made by Columbian Chemical Co., Ltd.) and 5 parts of ethyl acetate with a disper, they were kneaded with an Eiger mill to prepare a mill base. Thereto was added 6 parts of a polyester resin varnish, 4 parts of castor oil as a plasticizer, and 35 parts of ethyl acetate / toluene / isopropyl alcohol (mixing ratio: 40/40/20) as a diluent solvent to obtain a resist composition.
In the resist composition, Zahn Cup No. 3 was added for 15 seconds to obtain a coating solution.
Electro copper plating was performed on the surface of an iron roll having a width of 1,000 mm, an outer diameter of 200 mm, and an inner diameter of 100 mm (plating thickness: 80 μm).
The coating solution was applied to the surface and dried at 23 ° C. for 45 minutes. The resist film thickness after drying was 3 μm.
Subsequently, the resist layer was ablated by irradiating with a Nd: YAG laser having a wavelength of 1064 nm using a laser exposure apparatus Digilas (manufactured by Schepers). In the image pattern, L (line width) is 4 μm, which is the limit of the apparatus, and L (line) / S (space) = 4 μm / 300 μm concave line (35 mm from both ends of the roll is a blank part that does not form a concave line) ).
After the exposure, the cupric chloride aqueous solution was sprayed with a spray-type etching apparatus, and the copper was etched at 37 ° C. so that the width of the recess after etching was about 5 μm. Then, it washed with water and dried.
The resist layer of the non-ablation part was peeled off using the diluting solvent used in the preparation of the resist composition to obtain a roll whose entire surface was copper. The recess depth at this time was 0.5 μm.
Thereafter, in order to impart surface hardness, electrochrome plating was performed (plating thickness 1 μm) to obtain a printing plate.

<Evaluation>
The confirmation of the presence or absence of disconnection, the measurement of the line width, and the measurement of the variation in the line width were performed using a 3 CCD color confocal microscope (OPTELICS manufactured by Lasertec Corporation) for the line width of the printed line on the substrate.
The line width was measured at six points in the circumferential direction to obtain an average value.
For the measurement of the variation in line width, the difference between the maximum value and the minimum value of the line width in the entire region was obtained, and the value was used as the variation.
The sheet resistance value was measured according to JIS K7194 using a resistivity meter (Lorestar GX MCP-T700 manufactured by Mitsubishi Chemical Corporation).
The transmittance (light transmittance) was measured according to JIS K7361-1 using a haze meter (NDH4000 manufactured by Nippon Denshoku Industries Co., Ltd.).

  The evaluation results are summarized in Table 1.

As is clear from the results in Table 1, the conductive patterns obtained in Examples 1 to 11 had few disconnections and excellent light transmittance.
In addition, the conductive patterns obtained in Examples 1 to 11 were able to form recesses with a narrow line width, the variation in the line width was small, and the sheet resistance value was a small value. It was.
In Comparative Examples 1 and 2, the line width was increased due to the side etch effect during etching, and the line width variation was increased due to variations during etching. Moreover, in Comparative Example 4 and Comparative Example 5 in which the line width was set to be thin, since the recess depth was insufficient, the amount of conductive ink transferred to the substrate was insufficient, and disconnection was recognized.

10: concave line, 12: metal layer, 14: line width of concave line, 16: depth of concave line, 100: printing plate, 102: metal plate, 104: cutting portion, 106: concave line, 108: FIG. , L ¹ : line width of the concave line 106, L ^s : distance between the two concave lines 106

Claims (13)

Preparing a printing plate having a concave line formed by cutting on its surface;
A step of holding conductive ink in the concave portion of the concave line;
Transferring the conductive ink held in the recess to the substrate; and
A method for forming a conductive pattern, comprising a step of sintering the conductive ink transferred to the substrate.   The conductive pattern forming method according to claim 1, wherein the concave line is a concave line formed by cutting using a cutting tool.   The conductive pattern forming method according to claim 2, wherein the cutting tool does not vibrate at a constant frequency in a direction perpendicular to a surface to be cut of the printing plate during cutting.   The method for forming a conductive pattern according to any one of claims 1 to 3, wherein the printing plate is a metal plate.   The conductive pattern forming method according to claim 4, wherein the metal plate is a metal roll.   The conductive pattern forming method according to claim 1, wherein the concave line includes a concave line having a line width of 10 μm or less.   The conductive pattern according to any one of claims 1 to 6, wherein the holding step, the transferring step, and the sintering step are performed during a period from one feeding of the substrate to winding. Forming method.   The conductive pattern forming method according to any one of claims 1 to 7, wherein in the sintering step, the sintering is performed by at least one selected from the group consisting of heat and light.   The conductive pattern forming method according to claim 1, wherein the sintering is performed by heating at a temperature of 80 ° C. to 200 ° C.   The volume resistance value of the said conductive ink is 20 microhm * cm or less, The conductive pattern formation method of any one of Claims 1-9.   The conductive pattern forming method according to claim 1, wherein the conductive ink is a conductive ink containing silver nanoparticles. A printing plate for forming a conductive pattern having a concave line formed by cutting on its surface. Preparing a printing plate precursor, and
The manufacturing method of the printing plate for electroconductive pattern formation including the process of forming a concave line on the surface of the said printing plate precursor by cutting.