CN107249759B

CN107249759B - Pattern forming method, substrate with transparent conductive film, device, and electronic apparatus

Info

Publication number: CN107249759B
Application number: CN201680012681.0A
Authority: CN
Inventors: 新妻直人; 大屋秀信; 山内正好; 小俣猛宪
Original assignee: Konica Minolta Inc
Current assignee: Konica Minolta Inc
Priority date: 2015-03-02
Filing date: 2016-03-02
Publication date: 2020-06-26
Anticipated expiration: 2036-03-02
Also published as: CN107249759A; KR102003625B1; WO2016140284A1; JPWO2016140284A1; KR20170110111A; JP6652124B2

Abstract

The present invention addresses the problem of providing a pattern forming method, a substrate with a transparent conductive film, a device, and an electronic apparatus, which can increase the degree of freedom in setting the arrangement interval of fine lines containing a functional material without destabilizing the formation of the fine lines, by: a pattern forming method for forming a pattern containing a functional material by relatively moving a droplet discharge device 4 with respect to a substrate 1, discharging a plurality of droplets containing the functional material from the droplet discharge device 4 onto the substrate 1, and forming a linear liquid by uniting the plurality of droplets on the substrate 1, and depositing the functional material on the edge of the linear liquid when drying the formed linear liquid, wherein, in forming the linear liquid, a plurality of groups of droplet groups given from a plurality of nozzles 41 are given to pixel groups arranged in parallel with respect to a nozzle row 40 of the droplet discharge device 4 in a direction intersecting the nozzle row 40, and the plurality of groups of droplets are united to form the linear liquid extending in the direction intersecting the nozzle row 40.

Description

Pattern forming method, substrate with transparent conductive film, device, and electronic apparatus

Technical Field

The present invention relates to a pattern forming method, a substrate with a transparent conductive film, a device, and an electronic apparatus, which can improve the degree of freedom in setting the arrangement interval of thin lines containing a functional material without destabilizing the formation of the thin lines.

Background

As a method for forming a fine line pattern containing a functional material, a method using a photolithography technique has been widely used.

However, the photolithography technique involves a large loss of material and a complicated process. Therefore, a method in which the loss of various materials is small and the process is simple has been studied.

For example, there is a method of forming a fine line pattern by applying droplets containing a functional material to a substrate by an ink jet method or the like, but in the ink jet method, it is generally difficult to form a fine line pattern having a line width of several μm because the width of a fine line is not equal to or smaller than the diameter of a discharged droplet.

On the other hand, there is a method of: after a water repellent is applied to the entire surface of a substrate in advance, a part of the water repellent is hydrophilized with a laser or the like to form a hydrophilic water-repellent pattern (i.e., a pattern formed of a hydrophilic portion and a water-repellent portion), and droplets are applied thereto by ink-jet to form fine lines. However, this method involves applying a water repellent agent and forming a hydrophilic water-repellent pattern by laser, which complicates the process.

In this regard, the following methods are proposed: a functional material, which is a solid component in the liquid droplet, is deposited on the peripheral edge of the liquid droplet by convection inside the liquid droplet, thereby forming a pattern having a width smaller than that of the liquid droplet (patent document 1).

According to this method, a thin line having a width of several μm or less in droplet diameter can be formed without requiring a special step.

It has also been proposed to form fine rings of conductive fine particles by this method and to form a transparent conductive film by connecting a plurality of the rings (patent document 2).

However, this technique has a problem that the number of intersections of the ring increases to produce a conductive path, and transparency is impaired.

In this regard, the present applicant has disclosed so far: when drying a liquid containing a functional material applied in a linear shape on a substrate, a pattern of parallel lines of 1 pair of thin lines is formed by depositing the functional material on the edge portion of the linear liquid by convection inside the liquid droplets, and a transparent conductive film formed of such a pattern of parallel lines is disclosed (patent document 3).

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 2005-95787

Patent document 2: WO2011/051952

Patent document 3: japanese patent laid-open No. 2014-38992

Disclosure of Invention

Problems to be solved by the invention

However, in the technique of patent document 3, if the arrangement interval of the thin lines constituting the parallel line pattern is set to be large in order to further improve the transparency of the transparent conductive film, etc., the formation of the thin lines may be unstable, and there is room for further improvement.

Accordingly, an object of the present invention is to provide a pattern forming method, a substrate with a transparent conductive film, a device, and an electronic apparatus, which can improve the degree of freedom in setting the arrangement interval of fine lines containing a functional material without destabilizing the formation of the fine lines.

Other problems of the present invention will become apparent from the following description.

Means for solving the problems

The above problems are solved by the following inventions.

1. The pattern forming method is a pattern forming method as follows: the method for manufacturing the liquid crystal display device includes discharging a plurality of droplets containing a functional material from a droplet discharge device onto a base material while relatively moving the droplet discharge device with respect to the base material, uniting the plurality of droplets on the base material to form a linear liquid, and depositing the functional material on an edge of the linear liquid to form a pattern containing the functional material when drying the linear liquid formed.

2. The pattern forming method described in the above 1, wherein the linear liquid is formed obliquely with respect to a relative movement direction of the droplet discharge device.

3. The pattern forming method according to 1 or 2, wherein the amount of droplets per 1 pixel is adjusted by a number of gray levels (order number).

4. The pattern forming method according to any one of 1 to 3, wherein an amount of liquid droplets to be applied in a direction of forming the linear liquid is adjusted to a range of 2.5[ pL/μm ] or more and 15[ pL/μm ] or less.

5. The pattern forming method according to any one of the above 1 to 4, wherein a dot diameter (ドット diameter) overlap ratio is adjusted to 20% or more and 60% or less per 1 pixel.

6. The method of forming a pattern according to any one of 1 to 5, wherein a contact angle of the liquid droplet discharged from the liquid droplet discharge device on the substrate is adjusted to be in a range of 10 ° to 25 °.

7. The pattern forming method according to any one of 1 to 6, wherein a treatment for promoting drying is performed when the linear liquid is dried.

8. The method of forming a pattern according to any one of 1 to 7, wherein a concentration range of the functional material is adjusted to a range of 0.01[ wt% ] or more and 1.0[ wt% ]orless.

9. The method of forming a pattern according to any one of 1 to 8, wherein the functional material is a conductive material or a precursor of a conductive material.

10. The pattern forming method according to any one of 1 to 9, wherein the base material has irregularities on a pattern forming surface.

11. A substrate with a transparent conductive film, comprising a transparent conductive film on a surface of the substrate, wherein the transparent conductive film comprises a pattern formed by the pattern forming method according to any one of the above 1 to 10.

12. A device comprising the substrate with a transparent conductive film according to 11.

13. An electronic device comprising the device of 12 above.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, it is possible to provide a pattern forming method, a substrate with a transparent conductive film, a device, and an electronic apparatus, which can improve the degree of freedom in setting the arrangement interval of fine lines containing a functional material without destabilizing the formation of the fine lines.

Drawings

Fig. 1 is a diagram conceptually illustrating how a parallel line pattern is formed by a linear liquid.

FIG. 2 is a diagram illustrating a comparative example.

Fig. 3 is a diagram illustrating another comparative example.

Fig. 4is a diagram conceptually illustrating an example of the pattern forming method of the present invention.

Fig. 5 is a diagram conceptually illustrating a linear liquid formed by the method of fig. 4.

Fig. 6 is a diagram conceptually illustrating a pattern of parallel lines formed by the method of fig. 4.

Fig. 7 is a diagram conceptually illustrating another example of the pattern forming method of the present invention.

Fig. 8 is a diagram conceptually illustrating a linear liquid formed by the method of fig. 7.

Fig. 9 is a diagram conceptually illustrating a parallel line pattern formed by the method of fig. 7.

Fig. 10 is a diagram illustrating a nozzle row.

Fig. 11 is a perspective cross-sectional view showing an example of a parallel line pattern formed on a base material.

Fig. 12 is a diagram illustrating an example of the transparent conductive film.

Fig. 13 is a diagram illustrating a substrate having concavities and convexities used in examples.

Fig. 14 is an optical micrograph of a fine line pattern.

Detailed Description

The mode for carrying out the present invention will be described below with reference to the drawings.

As shown in fig. 1(a), a linear liquid 2 containing a functional material is applied to a substrate 1.

The application of the linear liquid 2 to the substrate 1 can be performed using a droplet discharge device. Specifically, a linear liquid containing a functional material can be formed by discharging a plurality of droplets containing the functional material from the droplet discharge device while relatively moving the droplet discharge device with respect to the base material, and uniting the discharged droplets on the base material. The droplet discharge device can be constituted by, for example, an ink jet head included in an ink jet recording apparatus.

As shown in fig. 1(b), when the linear liquid 2 containing the functional material is evaporated and dried, the functional material is selectively deposited on the edge of the linear liquid 2 by utilizing the phenomenon of coffee stain (コーヒーステイン).

In order to promote the coffee spotting phenomenon, it is preferable to perform: conditions for drying the linear liquid 2 were set. That is, the drying of the linear liquid 2 disposed on the substrate 1 is faster at the edge than at the center, and the conductive material is locally deposited at the edge of the linear liquid 2. The edges of the linear liquid 2 are fixed by the deposited conductive material, and the subsequent shrinkage of the linear liquid 2 in the width direction due to drying is suppressed. As for the liquid of the linear liquid 2, a flow from the central portion toward the edge is formed to replenish the liquid at the portion lost by evaporation at the edge. By this flow, further conductive material is carried to the edge and accumulates. This flow is caused by the fixation of the contact line of the linear liquid 2 in the drying phase and the difference in the evaporation amount between the central portion and the edge of the linear liquid 2. Therefore, it is preferable to set conditions such as the concentration of the conductive material, the contact angle between the linear liquid 2 and the substrate 1, the amount of the linear liquid 2, the heating temperature of the substrate 1, the arrangement density of the linear liquid 2, or environmental factors such as temperature, humidity, and atmospheric pressure so as to promote the flow.

As a result, as shown in fig. 1(c), a coating film pattern (hereinafter, sometimes referred to as a parallel line pattern) 3 composed of thin lines containing a functional material is formed on the base 1. The parallel line pattern 3 formed by 1 line of the liquid 2 is composed of 1 set of 2 line segments (thin lines) 31, 32. In fig. 1(c), I represents the arrangement interval of the

thin wires

31 and 32.

The functional material is a material for imparting a specific function to the base material. The term "imparting a specific function" means, for example, that a conductive material is used as a functional material when the base material is imparted with conductivity, and that an insulating material is used as a functional material when the base material is imparted with insulation.

The functional material contained in the ink of the present invention is not particularly limited, and preferably includes conductive fine particles, conductive materials such as conductive polymers, insulating materials, semiconductor materials, optical filter materials, dielectric materials, and the like.

As described above, if a conductive material is used as the functional material, for example, the

thin lines

31 and 32 can be provided with conductivity. The transparent conductive film in which the

thin lines

31 and 32 are arranged on the substrate 1 in a stripe shape, a mesh shape, or the like is excellent in light transmittance. In the following description, a case where a conductive material is mainly used as a functional material will be described.

Since the

thin lines

31 and 32 are sufficiently thin, even if the functional material itself does not have transparency, it is difficult to see the thin lines, and transparency can be imparted to the transparent conductive film. On the other hand, with respect to the conductivity, the thinner the

thin lines

31, 32 are, the more easily the resistance value is increased.

Therefore, in the above-mentioned patent document 3, the

thin lines

31 and 32 are arranged in a dense state on the substrate 1 by reducing the formation width of the linear liquid 2 and reducing the arrangement interval I of the

thin lines

31 and 32, thereby ensuring the conductivity of the transparent conductive film, specifically, as shown in fig. 2, a plurality of droplets 20 given on the substrate 1 for forming 1 linear liquid are given using 1 nozzle 41 provided in the droplet discharge device 4, and thus a sufficiently thin linear liquid is formed, and α is a relative movement direction of the droplet discharge device 4 with respect to the substrate 1.

According to the subsequent studies by the present inventors, it has been found that the electrical resistance value can be suitably reduced and the electrical conductivity can be suitably improved by plating or the like of the

thin wires

31 and 32. From this, it is understood that even if the arrangement interval I of the

thin lines

31 and 32 is increased, high conductivity can be imparted to the transparent conductive film. In addition, from the viewpoint of further improving the transmittance of a transparent functional film such as a transparent conductive film, it is also preferable to increase the arrangement interval I between the

thin lines

31 and 32.

By increasing the formation width of the linear liquid 2, the arrangement interval I between the

thin lines

31 and 32 can be increased. The present inventors tried to increase the droplet supply amount in order to increase the formation width of the linear liquid 2.

In forming the linear liquid 2, it is attempted to increase the volume of each droplet 20 to be dispensed from the nozzle 4 onto the substrate 1, thereby increasing the amount of droplet dispensing. However, there is a limit to increasing the droplet volume from the viewpoint of stably discharging droplets from the nozzle. That is, there is a limit to increase the arrangement interval I between the

thin lines

31 and 32.

In addition, when the linear liquid 2 is formed, it is attempted to increase the amount of the droplets 20 to be dispensed by causing a plurality of droplets to be attached (ink) to each 1 pixel, that is, by causing the number of gradation steps (drops per dot) [ dpd ] to be 2 or more (see fig. 3). This makes it possible to increase the formation width of the linear liquid and increase the arrangement interval I between the

thin lines

31 and 32, but a new problem has been found that the larger the number of gradation steps, the more likely the generated

thin lines

31 and 32 are to have irregular portions (bulge).

In contrast, in the pattern forming method of the present invention, when forming the linear liquid 2, for the pixel groups arranged in parallel to the nozzle row of the droplet discharge device, a plurality of droplet groups given from a plurality of nozzles are given in sets in a direction intersecting the nozzle row, the plurality of sets of droplets are combined into one, and the linear liquid extending in the direction intersecting the nozzle row is formed. This can prevent the generated

thin wires

31 and 32 from being swollen, particularly when the formation width of the linear liquid 2 is increased and the arrangement interval I between the

thin wires

31 and 32 is increased. Therefore, with the pattern forming method of the present invention, the following effects are obtained: the degree of freedom in setting the arrangement interval I of the thin wire can be increased without destabilizing the formation of the thin wire containing the functional material. It is also known that, particularly when a conductive material is used as a functional material as in the case of forming a transparent conductive film, swelling is prevented, and the pattern resistance is reduced, thereby obtaining an effect that the conductivity can be suitably improved.

Further, by comparing the case where the arrangement interval I is set to be equally large by the method shown in the example of fig. 3 and the method according to the present invention, the anti-bulging property can be particularly improved by using the method according to the present invention. As will be described in detail later in the examples, this point can be seen from a comparison between fig. 14(a) showing a pattern formed by the method according to the present invention and fig. 14(d) showing a pattern formed by the method shown in the example of fig. 3.

Hereinafter, the present invention will be described in more detail.

Fig. 4is a diagram conceptually illustrating an example of the pattern forming method of the present invention, and shows a plan view of a base material.

The droplet discharge device 4 here has a nozzle row 40 including a plurality of nozzles 41a to 41j arranged in a row along the direction N.

The region of the surface of the substrate 1 to be a target of pattern formation may be regarded as being composed of a plurality of pixels as indicated by vertical and horizontal grids in the drawing. In the following description, in the case of a pixel (xy), x designates a column and y designates a row. For example, in the case of the pixel d4, d columns and 4 rows of pixels are shown. Each row is constituted by a plurality of pixels arranged in parallel with the direction N of the nozzle column 40, and each column is constituted by a plurality of pixels arranged in parallel with the direction N orthogonal to the direction of the nozzle column 40.

The droplets 20 containing the functional material are discharged from the droplet discharge device 4 onto the substrate 1 while relatively moving the droplet discharge device 4 with respect to the substrate 1, and the relative movement direction α is set to a direction perpendicular to the direction N of the nozzle row 40.

During this relative movement, the droplets 20 are applied to the pixel group including the plurality of pixels (d1, e1, f1) arranged in parallel with the direction N of the nozzle row 40 from the plurality of

nozzles

41d, 41e, 41f, respectively. These droplets 20 given for a pixel group are sometimes referred to as a droplet group. By assigning the

nozzles

41d, 41e, and 41f to the respective pixels (d1, e1, and f1) constituting the pixel group, the liquid droplets 20 can be individually applied to the respective pixels (d1, e1, and f 1).

Next, when the droplet discharge apparatus 4is relatively moved by 1 pixel portion in the relative movement direction α, the next droplet 20, that is, the next droplet group, is given from each of the plurality of

nozzles

41d, 41e, and 41f to the next pixel group consisting of the plurality of pixels (d2, e2, and f2) arranged in parallel to the direction N of the nozzle row 40, and this is repeated, whereby a plurality of droplet groups can be given in the direction intersecting the direction N of the nozzle row 40, and here, a plurality of droplet groups are given in the direction orthogonal to the direction N of the nozzle row 40.

By uniting the droplets 20 constituting these plural droplet groups, the linear liquid 2 extending in the direction intersecting the direction N of the nozzle row 40 can be formed as shown in fig. 5.

Further, when the linear liquid 2 is dried, the functional material is deposited on the edge of the linear liquid 2, whereby the parallel line pattern 3 containing the functional material can be formed as shown in fig. 6. The parallel line pattern 3 formed by 1 line of the liquid 2 is composed of 1 set of 2 line segments (thin lines) 31, 32.

According to the above method, when the linear liquid 2 is formed, the droplet group is given from the plurality of nozzles to the pixel group including the plurality of pixels arranged in parallel to the nozzle row 40, whereby the formation width of the linear liquid 2 can be freely increased. Further, even when the arrangement interval I of the

thin wires

31 and 32 generated by the linear liquid 2 is increased, the occurrence of the bulge can be appropriately prevented. That is, the degree of freedom in setting the arrangement interval I of the

thin wires

31 and 32 can be increased without destabilizing the formation of the

thin wires

31 and 32 containing the functional material.

In the formation of the linear liquid 2, the droplets 20 to be applied to the substrate 1 are applied not only integrally in the droplet group including the droplets 20 but also integrally between the droplet groups adjacent to each other in the direction intersecting the nozzle row 40.

In order to suitably realize such integration, the dot diameter (ドット diameter) of the droplet 20 is preferably large enough to have a size of 1 pixel. Specifically, the dot diameter of the droplet 20 is preferably set to be 1 pixel long or longer, more preferably 1 pixel long or longer, and the diagonal length is preferably set to be 1 pixel long or longer. The size relationship between the dot diameter of the droplet 20 and the size of 1 pixel can be set as appropriate by adjusting, for example, the pixel resolution, the droplet amount per 1 pixel, the contact angle of the droplet with respect to the substrate, and the like. Note that, the "pixel length of 1 pixel" may be a length of 1 side if the pixel is square, or a length of a long side if the pixel is rectangular.

The "dot diameter of the droplet 20" D [ mm ] can be calculated from the contact angle θ [ rad ] between the droplet 20 and the substrate, and the droplet volume V [ mm3] of the droplet 20 per 1 pixel, by the following equation.

[ mathematical formula 1]

The contact angle is a static contact angle, and can be determined, for example, by placing a droplet (about 5. mu.l) to be measured on the substrate 1 from a syringe under an environment of 25 ℃ and 50% RH using DM-500 manufactured by Kyowa Kagaku K.K., and measuring the angle formed by the tangent line at the end of the droplet and the substrate surface.

The contact angle of the liquid droplet 20 discharged from the liquid droplet discharging device 4 on the substrate 1 is preferably adjusted to be in the range of 10 ° to 25 °. This makes it possible to make the width of each of the

thin lines

31 and 32 narrower, to further improve the transmittance, to further prevent swelling, and to further reduce the pattern resistance.

The adjustment of the amount of droplets per 1 pixel can be performed by adjusting the volume of droplets discharged from the nozzle (the volume per 1 droplet), but is preferably performed by adjusting the number of droplets given to 1 pixel, that is, the number of gradation steps [ dpd ]. That is, the liquid droplets 20 given to 1 pixel may be constituted by only 1 liquid droplet discharged from the nozzle, or may be constituted by 2 or more liquid droplets discharged from the nozzle. In the example of fig. 3, in order to provide a sufficient formation width to the linear liquid, the number of gradation steps needs to be set large, but in the present invention, the number of gradation steps can be set relatively small so as to be inversely proportional to the number of pixels constituting the pixel group.

The amount of droplet supply in the direction of formation of the linear liquid 2 is preferably adjusted to a range of 2.5[ pL/μm ] or more and 15[ pL/μm ] or less. This can further increase the arrangement interval I between the

thin wires

31 and 32, thereby further improving the transmittance, and further preventing swelling and further reducing the pattern resistance.

The dot diameter overlap ratio of 1 pixel is preferably adjusted to 20% or more and 60% or less. This can appropriately integrate the droplets in the process of forming the linear liquid, and can further prevent the swelling and further reduce the pattern resistance. In this case, "the overlapping ratio of dot diameters per 1 pixel" [% ] is a value calculated from ([ D-D ]/D) · 100, "the overlapping ratio of dot diameters per 1 pixel is adjusted to 20% or more and 60% or less" may be in other words, a relationship of 20% ≦ ([ D-D ]/D) · 100 ≦ 60% is satisfied. Wherein D is the dot diameter D [ mm ] of the droplet 20, and D is the inter-dot distance [ mm ]. The dot pitch d [ mm ] corresponds to the arrangement pitch of the plurality of nozzles constituting the nozzle row 40 of the droplet discharge device 4. The inter-dot distance d [ mm ] may also be referred to as an inter-center distance of the droplets 20 adjacently given in the nozzle row 40 direction.

From the viewpoint of more remarkably exhibiting the effects of the present invention, it is particularly preferable to adjust the amount of droplet supply in the direction of formation of the linear liquid 2 to the range of 2.5[ pL/μm ] to 15[ pL/μm ] and to adjust the overlap ratio of the dot diameter per 1 pixel to the range of 20% to 60%, and it is further preferable to adjust the contact angle on the substrate 1 of the droplet 20 discharged from the droplet discharge device 4 to the range of 10 ° to 25 ° after these conditions are satisfied.

According to the present invention, the time required for the wetting and spreading of the droplets given on the substrate can be shortened also in the formation of the linear liquid. For example, in the example of fig. 3, it takes a relatively long time until the wetting spread of the droplets given to 1 pixel to the predetermined range in the width direction of the linear liquid, but in the present invention, the droplets can be given more directly to the predetermined range in the width direction of the linear liquid by giving the droplet group to the pixel group composed of a plurality of pixels arranged in parallel with the nozzle row. Therefore, even when a wide linear liquid is formed, the liquid can be formed quickly.

The advantage of being able to shorten the time required for the wetting and spreading of the droplets given on the substrate is effectively utilized, and when drying the linear liquid 2, the treatment for promoting drying can be suitably performed. From the viewpoint of stably forming the parallel line pattern, it is preferable to perform drying relatively slowly to wait for wet spreading of the droplets, but according to the present invention, since the time required for wet spreading of the droplets can be shortened as described above, the parallel line pattern can be stably formed even in the case where the process of promoting drying is performed.

Examples of the treatment for promoting drying include heating, air blowing, irradiation with energy rays, and the like, and 1 or 2 or more of these may be used in combination.

A drying device (also referred to as a dryer) that promotes drying of the linear liquid is preferably used. The drying device may be configured to perform the above-described drying process, and examples thereof include a heater, a blower, an energy beam irradiation device, and the like, and 1 or 2 or more of these may be combined.

Further, the pattern forming method of the present invention can be suitably used even when a substrate having irregularities is subjected to pattern formation, taking advantage of the fact that the time required for the wetting and spreading of droplets given on the substrate can be shortened. That is, the pattern formation can be suitably performed on a substrate having irregularities such as concave curved surfaces and convex curved surfaces on the pattern formation surface. As described above, the time required for the wet spreading of the droplets can be shortened, and the time from the administration of the droplets to the drying can be shortened. Therefore, when a sufficient margin is not given to the flow of the liquid droplets given to the inclined surface of the unevenness by gravity or the like, for example, the linear liquid can be dried to form the parallel line pattern. When the substrate having irregularities is subjected to patterning, it is particularly preferable to carry out a treatment for promoting drying. Even in the case where the parallel line pattern is formed on the inclined surface, the flow of the liquid droplets is prevented, so that the pattern accuracy is excellent. Further, for example, in the case of patterning a substrate having irregularities, the adhesion of the pattern to the substrate is easily maintained, as compared with the case of performing a bending process for imparting irregularities after patterning a flat substrate.

Further, in the present invention, by applying a droplet group to a pixel group including a plurality of pixels arranged in parallel with the nozzle row, a sufficient formation width can be applied to the linear liquid with a relatively small number of gradation steps. For example, in the example of fig. 3, in order to provide a sufficient formation width to the linear liquid, the number of gradation steps must be set large, whereas in the present invention, the number of gradation steps can be set small so as to be inversely proportional to the number of pixels constituting the pixel group. The number of gray levels can be reduced by reducing the number of droplets to be supplied to 1 pixel from 1 nozzle, that is, by increasing the speed of relative movement of the droplet discharge device with respect to the base material. By increasing the speed of the relative movement, the formation speed of the linear liquid can be increased. As a result, it is possible to prevent a difference in progress of drying in the longitudinal direction of the linear liquid, which also contributes to prevention of occurrence of swelling. That is, from the viewpoint of preventing occurrence of swelling, it is preferable that each of the 1 linear liquids be dried simultaneously in the entire linear liquid, and according to the present invention, drying can be performed in a more desirable state.

In the above description, the case where the linear liquid is formed along the relative movement direction of the droplet discharge device has been described, but the present invention is not limited to this. It is also preferable to form the linear liquid obliquely with respect to the relative movement direction of the droplet discharge means.

Fig. 7 is a diagram conceptually illustrating another example of the pattern forming method of the present invention, and shows a plan view of a base material.

In the illustrated example, as described below, the linear liquid 2 is formed obliquely with respect to the relative movement direction α of the droplet discharge device 4.

In the course of this relative movement, the droplets 20, that is, the droplet groups, are applied from the respective nozzles of the plurality of

nozzles

41a, 41b, and 41c to the pixel group including the plurality of pixels (a1, b1, and c1) arranged in parallel with the direction N of the nozzle row 40.

nozzles

41b, 41c, and 41d to the next pixel group consisting of the plurality of pixels (b2, c2, and d2) arranged in parallel to the direction N of the nozzle row 40, and the plurality of droplet groups are given in the direction inclined to the direction N of the nozzle row 40 by repeating this.

That is, in the illustrated example, when selecting a pixel group to be given to the droplet 20, the next pixel group is selected from the pixels constituting the next row so as to be shifted by a predetermined number of pixels (1 pixel in the illustrated example) in the nozzle row direction N with respect to each pixel constituting the pixel group selected earlier.

By integrating the droplets 20 constituting these plural droplet groups, as shown in fig. 8, the linear liquid 2 extending in a direction inclined with respect to the direction N of the nozzle row 40, that is, in a direction inclined with respect to the relative movement direction of the droplet discharge device 4 can be formed.

Further, when the linear liquid 2 is dried, the functional material is deposited on the edge of the linear liquid 2, whereby the parallel line pattern 3 containing the functional material can be formed as shown in fig. 9. The parallel line pattern 3 formed by 1 line-shaped liquid 2 is composed of 1 set of 2 line segments (thin lines) 31, 32. Parallel line patterns 3 are formed obliquely with respect to the relative movement direction of the droplet discharge device 4.

As described above, when the linear liquid 2 is formed obliquely with respect to the relative movement direction α of the droplet discharge device, the formation width of the linear liquid 2 can be freely increased by applying the droplet group to the pixel group composed of the plurality of pixels arranged in parallel with the nozzle row 40 from the plurality of nozzles, and further, when the arrangement interval I of the

thin lines

31, 32 generated from the linear liquid 2 is increased, the occurrence of the bulge can be appropriately prevented, that is, when the formation of the

thin lines

31, 32 containing the functional material is not made unstable, the degree of freedom in setting the arrangement interval I of the

thin lines

31, 32 can be increased.

In the above example, the case where the linear liquid 2 is formed in the direction inclined by 45 ° with respect to the relative movement direction α of the droplet discharge device has been described, but the inclination angle is not limited to this.

In the above description, the case where the number of pixels constituting the pixel group is set to 3 pixels has been described, but the present invention is not limited to this, and the

thin lines

31 and 32 can be set appropriately so as to have a desired arrangement interval I. Therefore, the degree of freedom in setting the arrangement interval I is high. The number of pixels constituting a pixel group is preferably set to a range of 2 to 20 pixels, for example, and more preferably to a range of 2 to 10 pixels.

In the above description, the case where the base material is fixed and the droplet discharge device is moved has been mainly described, but the present invention is not limited to this, and at least one of the base material and the droplet discharge device is moved so that the droplet discharge device can be moved relative to the base material.

In the above description, the case where the droplet discharge device has a plurality of nozzles arranged in a row has been described, but the present invention is not necessarily limited to this. For example, as shown in fig. 10, the droplet discharge device 4 may have a plurality of nozzles arranged in a plurality of rows. In this case, the direction of the nozzle row corresponds to the arrangement direction N of the entire plurality of nozzles.

The functional material contained in the liquid discharged from the droplet discharge device to the base is not particularly limited, but is preferably a conductive material or a conductive material precursor. The conductive material precursor is a substance that can be changed into a conductive material by performing appropriate treatment.

As the conductive material, for example, conductive fine particles, conductive polymer, and the like can be preferably exemplified.

The conductive fine particles are not particularly limited, and fine particles of Au, Pt, Ag, Cu, Ni, Cr, Rh, Pd, Zn, Co, Mo, Ru, W, Os, Ir, Fe, Mn, Ge, Sn, Ga, In, and the like can be preferably used, and among these, if metal fine particles such as Au, Ag, Cu are used, a circuit pattern having low resistance and corrosion resistance can be formed, and therefore, such particles are more preferably used. From the viewpoint of cost and stability, Ag-containing metal fine particles are most preferable. The average particle diameter of these metal fine particles is preferably in the range of 1 to 100nm, more preferably in the range of 3 to 50 nm.

In addition, carbon fine particles are also preferably used as the conductive fine particles. As the carbon fine particles, graphite fine particles, carbon nanotubes, fullerenes, and the like can be preferably exemplified.

The conductive polymer is not particularly limited, and preferably a pi-conjugated conductive polymer is used.

The pi-conjugated conductive polymer is not particularly limited, and a chain conductive polymer such as polythiophene, polypyrrole, polybenzazole, polycarbazole, polyaniline, polyacetylene, polyfuran, polyparaphenylene vinylene, polyparaphenylene sulfide, polyoxo, polybenzothiophene, or polysulfide can be used. Among them, polythiophenes and polyanilines are preferable in terms of obtaining high conductivity. Polyethylene dioxythiophene is most preferred.

The conductive polymer more preferably contains the above-mentioned pi-conjugated conductive polymer and a polyanion. Such a conductive polymer can be easily produced by chemically oxidatively polymerizing a precursor monomer that forms a pi-conjugated conductive polymer in the presence of a polyanion and an appropriate oxidizing agent and an oxidation catalyst.

The polyanion is a substituted or unsubstituted polyalkylene group, a substituted or unsubstituted polyalkenylene group, a substituted or unsubstituted polyimide, a substituted or unsubstituted polyamide, a substituted or unsubstituted polyester, and a copolymer thereof, and is composed of a structural unit having an anionic group and a structural unit having no anionic group.

The polyanion is a solubilized polymer for solubilizing a pi-conjugated conductive polymer in a solvent. Further, the anionic group of the polyanion functions as a dopant for the pi-conjugated conductive polymer, and improves the conductivity and heat resistance of the pi-conjugated conductive polymer.

The anionic group of the polyanion may be any functional group that can be doped by chemical oxidation to the pi-conjugated conductive polymer, and among them, a mono-substituted sulfate group, a mono-substituted phosphate group, a carboxyl group, a sulfo group, and the like are preferable from the viewpoint of ease of production and stability. Further, from the viewpoint of the doping effect of the functional group to the pi-conjugated conductive polymer, a sulfo group, a monosubstituted sulfate group, and a carboxyl group are more preferable.

Specific examples of the polyanion include polyvinylsulfonic acid, polystyrenesulfonic acid, polyallylsulfonic acid, polyethylethylbenzenesulfonic acid, polybutylacrylate sulfonic acid, poly-2-acrylamido-2-methylpropanesulfonic acid, polyisoprene sulfonic acid, polyvinylcarboxylic acid, polystyrenecarboxylic acid, polyallylcarboxylic acid, polyacrylocarboxylic acid, polymethacryloylcarboxylic acid, poly-2-acrylamido-2-methylpropanecarboxylic acid, polyisoprene carboxylic acid, and polyacrylic acid. These may be homopolymers or 2 or more kinds of copolymers.

Further, a polyanion having F (fluorine atom) in the compound may be used. Specifically, Nafion (manufactured by Dupont) containing a perfluorosulfonic acid group, フレミオン (manufactured by Asahi glass Co., Ltd.) comprising a perfluoro type vinyl ether containing a carboxylic acid group, and the like can be mentioned.

Of these, the sulfonic acid-containing compound is more preferable because the ink jet printing system is particularly excellent in ink ejection stability and high conductivity is obtained.

Among these, polystyrene sulfonic acid, polyisoprene sulfonic acid, polyethyl acrylate sulfonic acid, and polybutyl acrylate sulfonic acid are preferable. These polyanions exhibit an effect of excellent conductivity.

The polymerization degree of the polyanion is preferably in the range of 10 to 100000 monomer units, and more preferably in the range of 50 to 10000 monomer units from the viewpoint of solvent solubility and conductivity.

The conductive polymer can also preferably use the commercial materials. For example, conductive polymers consisting of poly (3, 4-ethylenedioxythiophene) and polystyrene sulfonic acid (abbreviated as PEDOT/PSS) have been marketed by h.c. starck as the cleevios series, Aldrich as PEDOT-PSS483095, 560598, Nagase Chemtex as the Denatron series. In addition, polyaniline is already commercially available as the ORMECON series by the daily chemical company.

As the liquid containing the functional material used for forming the linear liquid, 1 or 2 or more kinds of water, an organic solvent, or the like can be used in combination.

The organic solvent is not particularly limited, and examples thereof include alcohols such as 1, 2-hexanediol, 2-methyl-2, 4-pentanediol, 1, 3-butanediol, 1, 4-butanediol, and propylene glycol; and ethers such as diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol monomethyl ether, dipropylene glycol monomethyl ether, and dipropylene glycol monoethyl ether.

In addition, the liquid containing the functional material may contain various additives such as a surfactant.

By using a surfactant, for example, in the case of forming a linear liquid by a droplet discharge method such as an ink jet method, it is possible to adjust the surface tension and the like to stabilize the discharge. The surfactant is not particularly limited, and a silicon surfactant or the like can be used. The silicone surfactant is a product obtained by polyether modification of a side chain or a terminal of dimethylpolysiloxane, and is commercially available, for example, KF-351A, KF-642 manufactured by shin-Etsu chemical industry, BYK347 and BYK348 manufactured by ビッグケミー. The amount of the surfactant added is preferably 1 wt% or less with respect to the total amount of the liquid forming the linear liquid 2.

The concentration range of the functional material in the liquid discharged from the droplet discharge device to the substrate is preferably adjusted to be 0.01[ wt% ] or more and 1.0[ wt% ] or less. This can further stabilize the formation of the

thin lines

31 and 32.

The substrate is not particularly limited, and examples thereof include glass, plastic (polyethylene terephthalate, polybutylene terephthalate, polyethylene, polypropylene, acrylic, polyester, polyamide, and the like), metal (copper, nickel, aluminum, iron, and the like, or an alloy thereof), ceramic, and the like, and these can be used alone or in a bonded state. Among them, preferred are plastics, and polyolefins such as polyethylene terephthalate, polyethylene, and polypropylene are suitable.

Further, as described above, a substrate having irregularities is also preferably used. The pattern forming method of the present invention can be suitably used also when a substrate having irregularities is patterned.

Fig. 11 is a partially cutaway perspective view showing an example of a parallel line pattern formed on a base material, and the cross section corresponds to a vertical cross section cut in a direction orthogonal to the direction in which the parallel line pattern is formed.

The 1 set of 2 thin lines (line segments) 31, 32 of the parallel line pattern 3 generated from 1 line-shaped liquid do not necessarily have to be island-shaped completely independent of each other. As shown in the drawing, the 2

line segments

31 and 32 are also preferably formed as a continuous body connected by the thin film portion 30 formed at a height lower than the height of the

line segments

31 and 32 between the

line segments

31 and 32.

The line widths W1, W2 of the

line segments

31, 32 of the parallel line pattern 3 are preferably 10 μm or less, respectively. When the thickness is 10 μm or less, the thickness is usually not visible, and therefore, it is more preferable from the viewpoint of improving the transparency. Considering the stability of the

line segments

31 and 32, the line widths W1 and W2 of the

line segments

31 and 32 are preferably in the range of 2 μm to 10 μm, respectively.

The widths W1, W2 of the

line segments

31, 32 are defined as the widths of the

line segments

31, 32 at a height half that of Y1, Y2, where Z is the height of the thinnest portion where the thickness of the functional material between the

line segments

31, 32 is the thinnest, and Y1, Y2 is the height of the

line segments

31, 32 protruding from Z. For example, when the pattern 3 has the thin film portion 30 described above, the height of the thinnest portion of the thin film portion 30 can be represented by Z. When the height of the thinnest portion of the functional material between the

line segments

31, 32 is 0, the line widths W1, W2 of the

line segments

31, 32 are defined as the width of the

line segments

31, 32 at a height half the height H1, H2 of the

line segments

31, 32 from the surface of the base material 1.

Since the line widths W1 and W2 of the

line segments

31 and 32 constituting the parallel line pattern 3 are extremely fine as described above, the heights H1 and H2 of the

line segments

31 and 32 from the surface of the base material 1 are preferably high from the viewpoint of securing the cross-sectional area and achieving a low resistance. Specifically, the heights H1, H2 of the

line segments

31, 32 are preferably in the range of 50nm to 5 μm.

Further, from the viewpoint of improving the stability of the parallel line pattern 3, the H1/W1 ratio and the H2/W2 ratio are preferably in the ranges of 0.01 to 1, respectively.

From the viewpoint of further increasing the thinning of the parallel line patterns 3, it is preferable that the height Z of the thinnest portion where the thickness of the functional material is thinnest between the

line segments

31, 32, specifically, the height Z of the thinnest portion of the thin film portion 30 is within a range of 10nm or less. Most preferably, the thin film portion 30 is provided in the range of 0 < Z.ltoreq.10 nm in order to achieve a balance between transparency and stability.

Further, in order to further increase the thinning of the parallel line pattern 3, the H1/Z ratio and the H2/Z ratio are each preferably 5 or more, more preferably 10 or more, and particularly preferably 20 or more.

In the present invention, the range of the arrangement interval I of the

segments

31 and 32 is not particularly limited, and can be appropriately set with a high degree of freedom as described above, and particularly, even when the arrangement interval I is increased, bulging can be appropriately prevented. Specifically, even when the arrangement interval I is set to a large value, for example, 50 μm or more, 100 μm or more, 200 μm or more, 300 μm or more, 400 μm or more, or 500 μm or more, the bulging can be appropriately prevented, and the formation of the

line segments

31 and 32 can be stabilized. According to the present invention, the arrangement interval I can be set to an optimum value as appropriate depending on the application in a state where the swelling is appropriately prevented. In the case of forming a transparent conductive film or the like, the arrangement interval I is preferably in the range of, for example, 100 μm to 1000 μm, and more preferably in the range of 100 μm to 500 μm.

The arrangement interval I between the

line segments

31 and 32 is the distance between the maximum protrusions of the

line segments

31 and 32.

Further, it is preferable that the line segment 31 and the line segment 32 have the same shape (the same cross-sectional area), and more specifically, it is preferable that the heights H1 and H2 of the line segment 31 and the line segment 32 have substantially the same value. Similarly, the line widths W1 and W2 of the line segment 31 and the line segment 32 are preferably set to be substantially equal to each other.

The

line segments

31, 32 do not necessarily have to be parallel, but the

line segments

31, 32 need not be joined over at least a certain length L in the line segment direction. Preferably, the

line segments

31, 32 are substantially parallel over at least some length L in the direction of the line segments.

The length L of the

line segments

31, 32 in the line segment direction is preferably 5 times or more, and more preferably 10 times or more, the arrangement interval I between the

line segments

31, 32. The length L and the arrangement interval I may be set corresponding to the formation length and the formation width of the pattern (linear liquid) 2.

The

line segments

31 and 32 may be connected to form a continuous body at the start point and the end point of the formation of the linear liquid (start point and end point of a certain length L in the line segment direction).

In addition, the

line segments

31 and 32 preferably have substantially equal line widths W1 and W2, and the line widths W1 and W2 are sufficiently smaller than the 2-line distance (arrangement interval I).

Further, it is preferable that the line segment 31 and the line segment 32 constituting the pattern 3 generated from 1 linear liquid are formed at the same time.

In particular, it is preferable that all of the

line segments

31 and 32 of the parallel line pattern 3 satisfy the following conditions (1) to (3). This makes it difficult to see the pattern, and therefore, the line segment can be stabilized while improving the transparency, and particularly, when the functional material is a conductive material, the effect of reducing the resistance value of the pattern is excellent.

(1) The height of each

line segment

31, 32 is H1, H2, and the height of the thinnest part between the line segments is Z, which is 5. ltoreq.H 1/Z and 5. ltoreq.H 2/Z.

(2) When the widths of the

line segments

31, 32 are W1, W2, W1 is 10 μm or less and W2 is 10 μm or less.

(3) The heights of the

line segments

31 and 32 are set to H1 and H2, respectively, 50nm < H1 < 5 μm and 50nm < H2 < 5 μm.

The pattern formed according to the present invention is also preferably subjected to post-treatment such as firing or plating, if necessary. When the functional material contains a conductive material, the post-treatment is preferably a treatment for improving the conductivity of the pattern.

The substrate with a transparent conductive film of the present invention has a transparent conductive film having a pattern formed by the above-described pattern forming method on the surface of the substrate.

Even when the functional material (conductive material) itself contained in the transparent conductive film is opaque, the pattern can be made less visible by making the linear liquid change into a parallel line pattern and thinning the line.

Fig. 12 is a diagram illustrating an example of the transparent conductive film. The transparent conductive film 5 is preferably formed as an aggregate of a plurality of parallel line patterns 3. The transparent conductive film 5 is preferably in the form of, for example, a stripe in which a plurality of parallel line patterns 3 are arranged in parallel in 1 direction as shown in fig. 12(a) and (b), or a screen (also referred to as a lattice) in which a plurality of parallel line patterns 3 are arranged in parallel in 1 direction and a plurality of parallel line patterns 3 are arranged in parallel in a direction intersecting with the patterns as shown in fig. 12(c) and (d). In the example of fig. 12(a) and (c), the parallel line patterns 3 are formed parallel to the sides of the base material 1, and the parallel line patterns 3 are formed obliquely to the sides of the base material 1 in the example of fig. 12(b) and (d).

The use of the substrate with a transparent conductive film is not particularly limited, and the substrate can be used for various devices included in various electronic apparatuses.

From the viewpoint of remarkably exerting the effects of the present invention, the substrate with a transparent conductive film can be preferably used as a transparent electrode for displays of various types such as liquid crystal, plasma, organic electroluminescence, and field emission, or as a transparent electrode used in touch panels, mobile phones, electronic paper, various solar cells, various electroluminescence light control elements, and the like.

Further, the substrate with the transparent conductive film is preferably used as a transparent electrode of a device. The device is not particularly limited, and for example, a touch panel sensor or the like can be preferably exemplified. The electronic device having these devices is not particularly limited, and a smartphone, a tablet terminal, or the like can be preferably exemplified.

In the above description, the configuration described for one embodiment can be applied to other embodiments as appropriate.

Examples

The following examples of the present invention are described, but the present invention is not limited to these examples.

1. Pattern formation

(example 1)

Composition of ink

As an ink (liquid containing a functional material), an ink of the following composition was prepared.

Silver nanoparticles (average particle diameter: 20 nm): 0.054 wt%

Surfactant (manufactured by ビッグケミー Co., Ltd. "BYK 348"): 0.05 wt%

Diethylene glycol monobutyl ether (abbreviation: DEGBE) (dispersion medium): 20 wt.%

Water (dispersion medium): balance of

< substrate >

As the substrate, a PET substrate 1 was prepared which had been surface-treated so that the contact angle of a liquid containing a functional material became 20.3 °. As the surface treatment, "PS-1M" manufactured by Futokyo electric appliances was used for the corona discharge treatment.

< formation of pattern >

The ink was discharged from the droplet discharge device (manufactured by コニカミノルタ corporation, "KM 1024 iLHE-30" (standard droplet capacity 30pL)) while relatively moving the droplet discharge device with respect to the substrate, and a plurality of linear liquids were formed along a direction inclined at 45 ° with respect to the relative movement direction α.

The coating interval of each linear liquid was controlled so that the sample for transmittance measurement became a value of a multiple of 2 line widths, and the sample for terminal resistance measurement became 1000 μm.

The linear liquid was evaporated and dried, and the functional material was selectively deposited on the edge of the linear liquid, thereby forming a parallel line pattern in a direction inclined at 45 ° to the relative movement direction α, and here, the drying of the linear liquid was promoted by performing pattern formation on a base material disposed on a stage heated to 70 ℃.

In the above-described pattern formation, the ink discharge by the droplet discharge device when the linear liquid is formed is controlled as follows.

Single drop amount (drop volume per 1 drop): 30[ pL ]

The number of pixels constituting a pixel group in the nozzle column direction: 7

Number of gray levels: 3[ dpd ]

The droplet supply amount for 1 linear liquid formation direction: 6.32[ pL/. mu.m ]

Overlap ratio of dot diameter: 48.3 [% ]

The resulting pattern is a slanted stripe as shown in fig. 12 (b).

(example 2)

Composition of ink

Silver nanoparticles (average particle diameter: 20 nm): 0.19 wt%

Surfactant (manufactured by ビッグケミー Co., Ltd. "BYK 348"): 0.05 wt%

Water (dispersion medium): balance of

< substrate >

As the substrate, the PET substrate 1 similar to example 1 was used.

< formation of pattern >

The same as in example 1 was performed, except that ink discharge by the droplet discharge device when the linear liquid was formed was controlled as follows.

Single drop size: 30[ pL ]

The number of pixels constituting a pixel group in the nozzle column direction: 2

Number of gray levels: 3[ dpd ]

The droplet supply amount for 1 linear liquid formation direction: 1.81[ pL/. mu.m ]

Overlap ratio of dot diameter: 48.3 [% ]

The resulting pattern is a slanted stripe as shown in fig. 12 (b).

(example 3)

Composition of ink

Silver nanoparticles (average particle diameter: 20 nm): 0.13 wt%

Surfactant (manufactured by ビッグケミー Co., Ltd. "BYK 348"): 0.05 wt%

Water (dispersion medium): balance of

< substrate >

As the substrate, the PET substrate 1 similar to example 1 was used.

< formation of pattern >

Single drop size: 30[ pL ]

The number of pixels constituting a pixel group in the nozzle column direction: 3

Number of gray levels: 3[ dpd ]

The droplet supply amount for 1 linear liquid formation direction: 2.71[ pL/. mu.m ]

Overlap ratio of dot diameter: 48.3 [% ]

The resulting pattern is a slanted stripe as shown in fig. 12 (b).

(example 4)

Composition of ink

Silver nanoparticles (average particle diameter: 20 nm): 0.036 wt%

Surfactant (manufactured by ビッグケミー Co., Ltd. "BYK 348"): 0.05 wt%

Water (dispersion medium): balance of

< substrate >

As the substrate, the PET substrate 1 similar to example 1 was used.

< formation of pattern >

Single drop size: 30[ pL ]

The number of pixels constituting a pixel group in the nozzle column direction: 8

Number of gray levels: 4[ dpd ]

The droplet supply amount for 1 linear liquid formation direction: 9.63[ pL/. mu.m ]

Overlap ratio of dot diameter: 53.0 [% ]

The resulting pattern is a slanted stripe as shown in fig. 12 (b).

(example 5)

Composition of ink

Silver nanoparticles (average particle diameter: 20 nm): 0.023 wt%

Surfactant (manufactured by ビッグケミー Co., Ltd. "BYK 348"): 0.05 wt%

Water (dispersion medium): balance of

< substrate >

As the substrate, the PET substrate 1 similar to example 1 was used.

< formation of pattern >

Single drop size: 30[ pL ]

Number of gray levels: 6[ dpd ]

The droplet supply amount for 1 linear liquid formation direction: 14.43[ pL/. mu.m ]

Overlap ratio of dot diameter: 58.9 [% ]

The resulting pattern is a slanted stripe as shown in fig. 12 (b).

(example 6)

Composition of ink

Silver nanoparticles (average particle diameter: 20 nm): 0.021 wt%

Surfactant (manufactured by ビッグケミー Co., Ltd. "BYK 348"): 0.05 wt%

Water (dispersion medium): balance of

< substrate >

As the substrate, the PET substrate 1 similar to example 1 was used.

< formation of pattern >

Single drop size: 30[ pL ]

The number of pixels constituting a pixel group in the nozzle column direction: 9

Number of gray levels: 6[ dpd ]

The droplet supply amount for 1 linear liquid formation direction: 16.25[ pL/. mu.m ]

Overlap ratio of dot diameter: 58.9 [% ]

The resulting pattern is a slanted stripe as shown in fig. 12 (b).

(example 7)

Composition of ink

Silver nanoparticles (average particle diameter: 20 nm): 0.24 wt.%

Surfactant (manufactured by ビッグケミー Co., Ltd. "BYK 348"): 0.05 wt%

Water (dispersion medium): balance of

< substrate >

As the substrate, the PET substrate 1 similar to example 1 was used.

< formation of pattern >

The same procedure as in example 1 was repeated, except that a droplet discharge apparatus ("KM 1024 iSHE" (standard droplet amount 6pL) manufactured by コニカミノルタ was used to form a linear liquid, and that ink discharge was controlled as follows.

Single drop size: 6[ pL ]

The number of pixels constituting a pixel group in the nozzle column direction: 6

Number of gray levels: 4[ dpd ]

The droplet supply amount for 1 linear liquid formation direction: 1.44[ pL/. mu.m ]

Overlap ratio of dot diameter: 19.6 [% ]

The resulting pattern is a slanted stripe as shown in fig. 12 (b).

(example 8)

Composition of ink

Silver nanoparticles (average particle diameter: 20 nm): 0.19 wt%

Surfactant (manufactured by ビッグケミー Co., Ltd. "BYK 348"): 0.05 wt%

Water (dispersion medium): balance of

< substrate >

As the substrate, the PET substrate 1 similar to example 1 was used.

< formation of pattern >

Single drop size: 6[ pL ]

Number of gray levels: 5[ dpd ]

The droplet supply amount for 1 linear liquid formation direction: 1.80[ pL/. mu.m ]

Overlap ratio of dot diameter: 25.3 [% ]

The resulting pattern is a slanted stripe as shown in fig. 12 (b).

(example 9)

Composition of ink

Silver nanoparticles (average particle diameter: 20 nm): 0.063 wt%

Surfactant (manufactured by ビッグケミー Co., Ltd. "BYK 348"): 0.05 wt%

Water (dispersion medium): balance of

< substrate >

As the substrate, the PET substrate 1 similar to example 1 was used.

< formation of pattern >

Single drop size: 30[ pL ]

Number of gray levels: 6[ dpd ]

The droplet supply amount for 1 linear liquid formation direction: 5.41[ pL/. mu.m ]

Overlap ratio of dot diameter: 58.9 [% ]

The resulting pattern is a slanted stripe as shown in fig. 12 (b).

(example 10)

Composition of ink

As the ink, the same ink as in example 1 was used.

< substrate >

As the substrate, the PET substrate 1 similar to example 1 was used.

< formation of pattern >

Single drop size: 30[ pL ]

Number of gray levels: 7[ dpd ]

The droplet supply amount for 1 linear liquid formation direction: 6.31[ pL/. mu.m ]

Overlap ratio of dot diameter: 61.0 [% ]

The resulting pattern is a slanted stripe as shown in fig. 12 (b).

(example 11)

Composition of ink

As the ink, the same ink as in example 1 was used.

< substrate >

As the substrate, a PET substrate 2 subjected to surface treatment so that the contact angle of the liquid containing the functional material became 9.6 ° was prepared. As the surface treatment, "PS-1M" manufactured by Futokyo electric appliances was used for the corona discharge treatment. The contact angle was adjusted by making the intensity of the surface treatment different from that of example 1.

< formation of pattern >

Single drop size: 30[ pL ]

Number of gray levels: 3[ dpd ]

Overlap ratio of dot diameter: 59.9 [% ]

The resulting pattern is a slanted stripe as shown in fig. 12 (b).

(example 12)

Composition of ink

As the ink, the same ink as in example 1 was used.

< substrate >

As the substrate, a PET substrate 3 was prepared which had been surface-treated so that the contact angle of the liquid containing the functional material became 10.4 °. As the surface treatment, corona discharge treatment was carried out using "PS-1M" manufactured by SIGHT-ELECTRIC MEASURING CORPORATION. The contact angle was adjusted by making the intensity of the surface treatment different from that of example 1.

< formation of pattern >

Single drop size: 30[ pL ]

Number of gray levels: 3[ dpd ]

Overlap ratio of dot diameter: 58.8 [% ]

The resulting pattern is a slanted stripe as shown in fig. 12 (b).

(example 13)

Composition of ink

As the ink, the same ink as in example 1 was used.

< substrate >

As the substrate, a PET substrate 4 subjected to surface treatment so that the contact angle of the liquid containing the functional material became 24.1 ° was prepared. As the surface treatment, corona discharge treatment was carried out using "PS-1M" manufactured by SIGHT-ELECTRIC MEASURING CORPORATION. The contact angle was adjusted by making the intensity of the surface treatment different from that of example 1.

< formation of pattern >

Single drop size: 30[ pL ]

Number of gray levels: 3[ dpd ]

Overlap ratio of dot diameter: 45.1 [% ]

The resulting pattern is a slanted stripe as shown in fig. 12 (b).

(example 14)

Composition of ink

As the ink, the same ink as in example 1 was used.

< substrate >

As the substrate, a PET substrate 5 was prepared which had been surface-treated so that the contact angle of the liquid containing the functional material became 26.7 °. As the surface treatment, corona discharge treatment was carried out using "PS-1M" manufactured by SIGHT-ELECTRIC MEASURING CORPORATION. The contact angle was adjusted by making the intensity of the surface treatment different from that of example 1.

< formation of pattern >

Single drop size: 30[ pL ]

Number of gray levels: 3[ dpd ]

Overlap ratio of dot diameter: 43.0 [% ]

The resulting pattern is a slanted stripe as shown in fig. 12 (b).

(example 15)

Composition of ink

Silver nanoparticles (average particle diameter: 20 nm): 0.039 wt%

Surfactant (manufactured by ビッグケミー Co., Ltd. "BYK 348"): 0.05 wt%

Water (dispersion medium): balance of

< substrate >

As the substrate, the PET substrate 1 similar to example 1 was used.

< formation of pattern >

While a droplet discharge device ("KM 1024 iLHE-30" (standard droplet volume 30pL) manufactured by コニカミノルタ) was relatively moved with respect to the substrate, ink was discharged from the droplet discharge device, and a plurality of linear liquids were formed along the relative movement direction α.

By evaporating and drying the linear liquid, the functional material is selectively deposited on the edge of the linear liquid, and a parallel line pattern is formed in the relative movement direction α, wherein the drying of the linear liquid is promoted by patterning the base material disposed on the stage heated to 70 ℃.

In the above-described pattern formation, ink discharge by the droplet discharge device when forming the linear liquid is controlled as follows.

Single drop amount (drop volume per 1 drop): 30[ pL ]

Number of gray levels: 3[ dpd ]

The droplet supply amount for 1 linear liquid formation direction: 8.94[ pL/. mu.m ]

Overlap ratio of dot diameter: 48.3 [% ]

The resulting pattern is a stripe pattern as shown in fig. 12 (a).

(example 16)

Composition of ink

As the ink, the same ink as in example 15 was used.

< substrate >

As the substrate, a product in which the PET substrate 1 similar to example 1 was stuck to the concave surface of the concave-surface-shaped glass shown in fig. 13 was used.

< formation of pattern >

Single drop amount (drop volume per 1 drop): 30[ pL ]

Number of gray levels: 3[ dpd ]

Overlap ratio of dot diameter: 48.3 [% ]

The pattern formed on the concave surface of the base material is a stripe pattern as shown in fig. 12 (a).

Comparative example 1

Composition of ink

As the ink, the same ink as in example 1 was used.

< substrate >

As the substrate, the PET substrate 1 similar to example 1 was used.

< formation of pattern >

Single drop size: 30[ pL ]

Number of pixels in nozzle row direction: 1

Number of gray levels: 21[ dpd ]

Overlap ratio of dot diameter: 73.0 [% ]

The resulting pattern was a striped pattern as shown in fig. 12 (b).

Comparative example 2

Composition of ink

As the ink, the same ink as in example 15 was used.

< substrate >

As the substrate, the PET substrate 1 similar to example 15 was used.

< formation of pattern >

The same procedure as in example 15 was repeated, except that the ink discharge by the droplet discharge device in the case of forming a linear liquid was controlled as follows.

Single drop size: 30[ pL ]

Number of pixels in nozzle row direction: 1

Number of gray levels: 21[ dpd ]

Overlap ratio of dot diameter: 73.0 [% ]

The resulting pattern is a stripe pattern as shown in fig. 12 (a).

2. Evaluation method

The properties and physical properties of the patterns formed in the examples and comparative examples were evaluated.

(1) Character of pattern

The following items (anti-swelling property, 2 line width and fine line width) were evaluated as pattern properties.

Anti-ballooning Property

The 2-line properties shown in tables 1 to 5 were obtained by observing 1 set of 2 thin lines by optical microscope observation, and the anti-bulging properties were evaluated according to the following evaluation criteria.

< evaluation criteria >

A: no generation of bulging

B: a little swelling is generated

C: generates a large amount of swelling

2 lines width

The 2 line widths (μm) are the intervals between 1 set of 2 fine lines measured by observation with an optical microscope. The measurement value corresponds to the above arrangement interval I.

Width of thin line

The fine line width (μm) is the width of 1 set of 2 fine lines measured by optical microscope observation. The measured values correspond to the widths W1 and W2 described above. Since the widths of 2 thin lines are substantially the same, the measured value of one thin line is used as the thin line width (μm).

(2) Physical property value

The following items (transmittance, sheet resistance, and terminal resistance) were evaluated as physical property values.

Transmittance (total light transmittance)

The transmittance (total light transmittance) (% T) was measured by using AUTOMATICHAZEMETER (MODELTC-HIIIDP) manufactured by Tokyo electrochrome corporation. The correction was performed using a base material without a pattern, and the total light transmittance of the formed pattern was measured.

Resistance of the terminal

The terminal resistance (Ω) was a value obtained by cutting a patterned base material into a strip of 100mm × 10mm long sides along the pattern forming direction, and measuring the resistance value between the terminals (i.e., between both ends of the longitudinal direction of the strip region).

The evaluation results are shown in tables 1 to 5.

[ Table 4]

[ Table 5]

3. Evaluation of

Comparing examples 1 to 16 shown in tables 1 to 4 with comparative examples 1 and 2, it was found that: according to the present invention, it is possible to suitably prevent the generated

thin wires

31 and 32 from bulging, regardless of the thin wire forming direction, particularly even when the arrangement interval I of the

thin wires

31 and 32 is increased by increasing the forming width of the linear liquid 2. That is, according to the present invention, the following effects can be obtained: the degree of freedom in setting the arrangement interval I of the thin wires can be increased without destabilizing the formation of the thin wires containing the functional material.

In particular, focusing on examples 2 to 6, it is clear from the results of examples 3 to 5 that the amount of droplet supply in the direction of formation of 1 linear liquid is in the range of 2.5[ pL/. mu.m ] or more and 15[ pL/. mu.m ] or less, whereby the line width of 2 lines (corresponding to the arrangement interval I) can be made larger, the transmittance can be further improved, swelling can be further prevented, and the resistance can be further reduced.

In particular, when attention is paid to examples 7 to 10, it is found that swelling can be further prevented and the electrical resistance can be further reduced by adjusting the dot diameter overlap ratio to 20% or more and 60% or less.

In particular, focusing attention on examples 11 to 14, it is apparent from the results of examples 13 and 14 that the contact angle of the liquid droplets discharged from the liquid droplet discharging device on the substrate is adjusted to a range of 10 ° -25 ° -or more, whereby the thin line widths of the

thin lines

31 and 32 can be further reduced, the transmittance can be further improved, the swelling can be further prevented, and the electric resistance can be further reduced.

Particularly, if attention is paid to examples 1 and 15, it is understood that the effects of the present invention are exhibited without depending on the angle of the thin line with respect to the head relative movement direction.

In particular, if example 16 is concerned, it is understood that the present invention is suitably used also in the case of patterning a substrate having an uneven surface.

5. Observation with an optical microscope

Fig. 14(a) to (d) show 4 optical micrographs. These are photographs taken of a thin line pattern formed by depositing a functional material on the edge of a linear liquid given on a substrate when the linear liquid is dried. In the figure, dark portions correspond to the base material, and linear bright portions correspond to thin lines formed on the base material.

Fig. 14(a) and (b) show an example of the present invention in which, when 1 line of liquid is formed, a plurality of sets of liquid droplets supplied from a plurality of nozzles to a pixel set including 3 pixels arranged in parallel with a nozzle row of a liquid droplet discharge device are supplied in a direction intersecting the nozzle row, and the liquid droplets are combined into one body to form a line of liquid extending in the direction intersecting the nozzle row.

In fig. 14(a), by setting the number of gradation levels to 5[ dpd ], a total of 15 droplets of droplets were caused to strike 3 pixels constituting a pixel group. In fig. 14(b), by setting the number of gradation levels to 7[ dpd ], a total of 21 droplets were made to strike on 3 pixels constituting a pixel group. It is known that: thus, even when the 2-line width is increased by setting the number of the striking droplets to be relatively large, the bulge is prevented.

On the other hand, fig. 14(c) and (d) are comparative examples, in which when 1 line of liquid is formed, a plurality of droplets not given to a pixel group but to 1 pixel are given in a direction intersecting with a nozzle row, and these droplets are unified, thereby forming a line of liquid extending in the direction intersecting with the nozzle row.

In fig. 14(c), by setting the number of gradation levels to 6[ dpd ], a total of 6 droplets of droplets were made to strike for 1 pixel. In fig. 14(d), by setting the number of gradation levels to 14[ dpd ], a total of 14 droplets of droplets were made to strike for 1 pixel. In fig. 14(c) in which the number of the landing droplets is relatively small, the occurrence of the bulge is hardly observed, but the 2-line width cannot be increased. It is known that: if the number of the impact droplets is increased as shown in fig. 14(d), the occurrence of the bulge becomes remarkable. It is thus known that: when the width of 2 lines is increased, the bulging cannot be prevented.

In particular, with respect to fig. 14(a) of the embodiment and fig. 14(d) of the comparative example, it is known that: although the amounts of droplets to be administered per unit length of the linear liquid are the same, even if the arrangement interval I is increased to the same extent, the anti-swelling property is remarkably excellent in fig. 14(a) in which the present invention is used. In the present invention, even if the number of impact droplets is further increased to increase the droplet supply amount and the arrangement interval I is further increased, the anti-swelling property can be suitably exhibited as shown in fig. 14 (b).

From the above results, it is also known that: according to the present invention, the degree of freedom in setting the arrangement interval I of the thin wire can be increased without destabilizing the formation of the thin wire containing the functional material.

Description of the symbols

1: base material

2: linear liquid

20: liquid droplet

3: parallel line pattern

31. 32: thin wire

4: liquid droplet discharging device

40: nozzle row

41. 41a to 41 j: nozzle with a nozzle body

Claims

1. A pattern forming method is a pattern forming method comprising: discharging a plurality of droplets containing a functional material from a droplet discharge device onto a base material while relatively moving the droplet discharge device with respect to the base material, integrally combining the plurality of droplets on the base material to form a linear liquid, and depositing the functional material on an edge of the linear liquid to form a pattern containing the functional material when drying the linear liquid,

in the formation of the linear liquid, a plurality of sets of droplet groups given from a plurality of nozzles to a pixel group arranged in parallel with a nozzle row of the droplet discharge device are given in a direction intersecting with the nozzle row of the droplet discharge device, and the plurality of sets of droplets are combined into one body to form the linear liquid extending in the direction intersecting with the nozzle row.

2. The pattern forming method according to claim 1, wherein the linear liquid is formed obliquely with respect to a relative movement direction of the droplet discharge device.

3. The pattern forming method as claimed in claim 1 or 2, wherein the droplet amount per 1 pixel is adjusted by a gray scale number.

4. The pattern forming method according to claim 1 or 2, wherein a droplet feed amount in a forming direction of the linear liquid is adjusted to a range of 2.5pL/μm or more and 15pL/μm or less.

5. The pattern forming method according to claim 1 or 2, wherein the dot diameter overlapping ratio per 1 pixel is adjusted to be 20% or more and 60% or less.

6. The pattern forming method according to claim 1 or 2, wherein a contact angle of the liquid droplet discharged from the liquid droplet discharge device on the substrate is adjusted to a range of 10 ° or more and 25 ° or less.

7. The pattern forming method according to claim 1 or 2, wherein a treatment for promoting drying is performed when the linear liquid is dried.

8. The pattern forming method according to claim 1 or 2, wherein a concentration range of the functional material is adjusted to a range of 0.01 wt% or more and 1.0 wt% or less.

9. The pattern forming method according to claim 1 or 2, wherein the functional material is a conductive material or a conductive material precursor.

10. The pattern forming method according to claim 1 or 2, wherein the base material has an unevenness on a pattern forming surface.

11. A substrate with a transparent conductive film, which has a transparent conductive film on a surface of the substrate, wherein the transparent conductive film comprises a pattern formed by the pattern forming method according to any one of claims 1 to 10.

12. A device having the substrate with a transparent conductive film according to claim 11.

13. An electronic device provided with the device according to claim 12.