JPWO2017056978A1 - Method for forming functional fine line pattern and functional fine line pattern - Google Patents

Abstract

The present invention relates to a method for forming a functional fine line pattern in which, when forming a plurality of functional fine lines from a line-like liquid containing a functional material, the functional fine lines are hardly visible even when the arrangement interval of the functional fine lines is widened. And providing a functional fine line pattern, the problem is that a plurality of linear liquids containing functional materials are applied on the substrate 1 so as not to overlap each other, Along with drying, a functional material is selectively deposited on the peripheral portion of the line-shaped liquid to form two thin wires 3 each having a pair of parallel lines 31 and then one of the thin wires 3. This is a method in which the functional thin lines are formed by the remaining portions of the thin wires 3 by removing the respective portions, and when the spacing between the functional thin wires is 300 μm or more and less than 750 μm, the line width of the functional thin wires is 2 μm or more and 7 μm or less. age, When the location distance was 750μm or 2.5mm or less, it is solved by the line width and 2μm or 5μm or less.

Description

  The present invention relates to a method for forming a functional fine line pattern and a functional fine line pattern. More specifically, when forming a plurality of functional fine lines from a plurality of line-like liquids containing a functional material, the arrangement of adjacent functional fine lines is provided. A method for forming a functional fine line pattern in which the interval can be easily set so that the interval is wider than the arrangement interval of two parallel line segments formed from a line-shaped liquid, and the functional fine line is difficult to visually recognize, and It relates to a functional thin line pattern.

  In recent years, transparent conductive films have been widely used in various electric devices such as touch panels, mobile phones, electronic paper, organic EL elements, and solar cells.

  A conventional transparent conductive film is formed by depositing a transparent conductive material such as ITO (Indium Tin Oxide) on the entire surface of the substrate, and then removing the unnecessary conductive film by laser processing. An electrode pattern is formed by the conductive film left without being used (Patent Documents 1 and 2).

  However, these methods have a problem from the viewpoint of productivity because the area of an unnecessary conductive film to be removed to form an electrode pattern increases, resulting in a long tact time.

JP 2007-243059 A JP 2013-152514 A Japanese Patent Laying-Open No. 2005-95787 (Method for forming an electrical wiring pattern with a narrow pitch)

  The inventor has attempted to form a transparent conductive film (also referred to as a transparent electrode) by an aggregate of conductive thin wires. Specifically, a conductive thin wire is formed by depositing a conductive material contained in a line-shaped liquid applied on a base material on both edges of the line-shaped liquid.

  The resulting conductive thin wire is sufficiently thin compared to the line width of the line-like liquid, so even if the conductive material itself does not have transparency, it is difficult to block light and imparts light transparency to the transparent conductive film. it can. However, due to the restriction that the conductive thin wires are arranged at a pitch corresponding to the line width of the line-shaped liquid, there is a limit to the further improvement in light transmittance, and the performance of the transparent conductive film is limited.

  According to the study by the present inventors, by arranging the conductive thin wires at a wide pitch that is not limited by the line width of the line-like liquid, the light transmittance is further improved and the performance of the transparent conductive film is further extracted. I found out that For example, in an electronic device in which an image display element is arranged on the back surface of a transparent conductive film such as a touch panel, a mobile phone, electronic paper, an organic EL element, etc., when displaying an image by improving the light transmittance of the transparent conductive film The loss of the amount of light can be suppressed. Thereby, energy saving can be realized and consumption of the battery can be suppressed. For example, in the case of a solar cell, it is expected that the power generation efficiency is improved by improving the light transmittance of the transparent conductive film.

  However, if the pitch of the conductive thin wires is too wide, each of the conductive thin wires will be in an isolated state, and the conductive property that cannot transmit light to the region having light transmission between the conductive thin wires. There is a problem that the fine line becomes conspicuous and the conductive fine line is easily visually recognized.

  Note that Patent Document 3 does not disclose a transparent conductive film and is intended to reduce the pitch of electric wiring patterns, and thus does not solve the above-described problems.

  Therefore, in the present invention, when forming a plurality of functional fine lines from a line-shaped liquid containing a functional material, two fine lines formed from the line-shaped liquid have an arrangement interval between adjacent functional fine lines. Functional fine line pattern forming method and function that can be easily set to be wider than the arrangement interval of parallel line segments, and that the functional fine lines are not easily seen even if the arrangement interval of the functional fine lines is widened It is an object to provide a fine line pattern.

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

  The above problems are solved by the following inventions.

1.
A plurality of line-shaped liquids containing functional materials are provided on the substrate so as not to overlap each other.
Next, as the line-shaped liquid is dried, the functional material is selectively deposited on the periphery of the line-shaped liquid, so that the line-shaped liquid has two pairs of parallel line segments. Each thin line is formed,
Next, by removing a part of each of the thin lines and forming functional thin lines by the remaining portions of the thin lines, the arrangement intervals of the plurality of functional thin lines are such that the thin lines formed from the line-shaped liquid A method of forming a functional fine line pattern that is larger than the arrangement interval of the two line segments that are parallel to each other.
When the arrangement interval of the functional thin wires is 300 μm or more and less than 750 μm, the line width of the functional thin wires is 2 μm or more and 7 μm or less,
A method for forming a functional fine line pattern, wherein when the arrangement interval of the functional fine lines is 750 μm or more and 2.5 mm or less, the line width of the functional fine lines is 2 μm or more and 5 μm or less.
2.
The contact angle of the linear liquid with respect to the substrate is 10 ° or more and 30 ° or less,
The amount of liquid droplets per pixel when applying the line-shaped liquid on the substrate is 300 pl or less,
2. The method for forming a functional fine line pattern according to 1 above, wherein a solid content concentration of the liquid containing the functional material for forming the linear liquid is 0.1% or more.
3.
3. The method for forming a functional thin line pattern according to 1 or 2, wherein the drying of the line-shaped liquid is performed by setting the temperature of the base material to 60 ° C. or more and 85 ° C. or less and drying with a suction air.
4).
The functionality according to the above 1, 2 or 3, wherein after forming the functional fine wire on the substrate, the surface of the functional fine wire is oxidized by heat treatment at 80 ° C or higher and 150 ° C or lower in the atmosphere. A method for forming a fine line pattern.
5).
5. The method for forming a functional fine line pattern according to 4, wherein a line width of the functional fine line is reduced by treatment with an electrolyte solution after the oxidation treatment.
6).
The functional material is a conductive material,
6. The method for forming a functional fine line pattern according to 5, wherein after the oxidation treatment, the functional fine wire is plated with a plating solution that is an electrolyte solution when the functional fine wire is plated.
7).
7. The method for forming a functional fine line pattern according to 6, wherein the plating process is a copper plating process.
8).
The functional material is a conductive material,
5. The method of forming a functional fine line pattern as described in 4 above, wherein after the oxidation treatment, the functional fine wire is subjected to copper plating treatment and then subjected to copper etching treatment to reduce the line width of the functional fine wire.
9.
9. The method for forming a functional fine wire pattern according to any one of 5 to 8, wherein the functional fine wire is subjected to nickel plating after the oxidation treatment.
10.
A functional fine line pattern in which a plurality of functional fine lines containing a functional material are arranged in parallel on a base material,
The arrangement interval of the functional thin wires is 300 μm or more and less than 750 μm,
A functional fine line pattern in which a line width of the functional fine line is 2 μm or more and 7 μm or less.
11.
A functional fine line pattern in which a plurality of functional fine lines containing a functional material are arranged in parallel on a base material,
The arrangement interval of the functional thin wires is 750 μm or more and 2.5 mm or less,
A functional fine line pattern in which a line width of the functional fine line is 2 μm or more and 5 μm or less.

  According to the present invention, when forming a plurality of functional fine lines from a line-shaped liquid containing a functional material, the two fine lines formed from the line-shaped liquid have an interval between adjacent functional thin lines. Functional fine line pattern forming method and function that can be easily set to be wider than the arrangement interval of parallel line segments, and that the functional fine lines are not easily seen even if the arrangement interval of the functional fine lines is widened A thin line pattern can be provided.

The top view explaining one Embodiment of the formation method of the functional fine wire pattern which concerns on this invention The top view explaining one Embodiment of the formation method of the functional fine wire pattern which concerns on this invention The top view explaining one Embodiment of the formation method of the functional fine wire pattern which concerns on this invention The top view explaining one Embodiment of the formation method of the functional fine wire pattern which concerns on this invention The figure explaining a mode that a line-like liquid is formed The figure explaining a mode that a fine line is formed from a line-like liquid Cross section of functional thin wire The top view explaining other embodiment of the formation method of the functional fine wire pattern concerning the present invention The top view explaining other embodiment of the formation method of the functional fine wire pattern concerning the present invention The top view explaining other embodiment of the formation method of the functional fine wire pattern concerning the present invention The top view explaining other embodiment of the formation method of the functional fine wire pattern concerning the present invention

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  1 to 4 are plan views for explaining an embodiment of a method for forming a functional fine line pattern according to the present invention.

  First, as shown in FIG. 1, a plurality of line-shaped liquids 2 containing a functional material are applied on a base material 1 in parallel. The application of the plurality of line-shaped liquids 2 is performed so that the line-shaped liquids 2 do not overlap each other.

  In the present invention, the substrate 1 is not particularly limited. For example, glass, plastic (polyethylene terephthalate, polybutylene terephthalate, polyethylene, polypropylene, acrylic, polyester, polyamide, etc.), metal (copper, nickel, aluminum, iron, etc.) Or alloys) and ceramics. These may be used alone or in a state where two or more different materials are bonded together. For example, when used as a transparent conductive film (transparent electrode) of a touch panel sensor, a plastic having transparency is preferable, and polyethylene terephthalate, polyolefin such as polyethylene and polypropylene, and the like are preferable.

  In the present invention, the functional material contained in the liquid (ink) for forming the line-shaped liquid 2 is not particularly limited as long as it is a material for imparting a specific function to the substrate 1. Giving a specific function means, for example, imparting conductivity to the substrate 1 using a conductive material, imparting insulation to the substrate 1 using an insulating material, and the like. As the functional material, for example, a conductive material, an insulating material, a semiconductor material, an optical filter material, a dielectric material, or the like can be used according to a required function. The functional material is preferably a material different from the material constituting the surface of the substrate 1 to which the functional material is applied.

  Each linear liquid 2 in the present embodiment is formed in a straight line extending along the Y direction in FIG. 1, and is arranged so that it is parallel in parallel at a constant interval along the X direction orthogonal to the Y direction. It is given on the material 1. Here, the four line-shaped liquids 2 are formed so as to be arranged in parallel at equal intervals. However, the number of the line-shaped liquids 2 provided on the substrate 1 may be plural, and is not particularly limited. .

  As a method for applying the line-shaped liquid 2 onto the substrate 1, a method of applying by an ink jet method is used. According to the inkjet method, a plurality of line-shaped liquids 2 juxtaposed on the substrate 1 can be formed with a high degree of freedom.

  As shown in FIG. 5, the line-like liquid 2 by the ink jet method is a process in which the base material 1 and an ink jet head (not shown) are relatively moved along the Y direction, and as shown in FIG. Then, it is ejected to form a plurality of dots d on the substrate. Adjacent dots d, d are landed so as to overlap each other and are united on the base material, thereby forming one line-like liquid 2 extending in the Y direction.

  Next, the plurality of line-shaped liquids 2 arranged in parallel on the substrate 1 are dried. As the line-shaped liquid 2 is dried, the functional material is selectively deposited on the peripheral edge 21 of the line-shaped liquid 2 by the coffee stain phenomenon. That is, when the line-shaped liquid 2 applied on the substrate 1 is dried as shown in FIG. 6 (a), the drying is faster in the peripheral portion 21 than in the central portion 22 shown in FIG. 6 (b). First, the functional material is locally deposited on the peripheral portion 21. The peripheral portion 21 of the line-shaped liquid 2 is fixed by the deposited functional material, and shrinkage in the width direction of the line-shaped liquid 2 due to subsequent drying is suppressed. In the line-shaped liquid 2, as indicated by an arrow in FIG. 6B, a flow from the central portion 22 toward the peripheral portion 21 is formed so as to supplement the liquid lost by evaporation at the peripheral portion 21. Due to this flow, further functional material is carried to the peripheral edge 21 and deposited.

  As a result, as shown in FIG. 6C, the thin line 3 including the functional material is formed on the base material 1. FIG. 2 shows an assembly of four thin wires 3 formed on the substrate 1. The fine line 3 formed from one line-shaped liquid 2 has a shape along the shape of the peripheral edge 21 of the line-shaped liquid 2. For this reason, as shown in FIG. 2, the thin line 3 formed from each line-shaped liquid 2 has the line segments 31 and 31 which consist of a set of two mutually parallel straight lines, respectively. These line segments 31 and 31 are formed of a functional material deposited on both edge portions along the length direction of the peripheral edge portion 21 of the line-shaped liquid 2. L1 in FIG. 2 is an arrangement interval along the X direction of a pair of parallel line segments 31 and 31 formed from one line-shaped liquid 2.

  It is preferable to promote the formation of a flow that carries the functional material in the line-shaped liquid 2 to the peripheral edge 21. For example, the solid content concentration, the contact angle of the line-shaped liquid 2 with respect to the substrate 1, the amount of the line-shaped liquid 2, the heating temperature of the substrate 1, the arrangement density of the line-shaped liquid 2, or environmental factors such as temperature, humidity, and atmospheric pressure By adjusting the conditions, the peripheral portion 21 of the line-shaped liquid 2 can be fixed early, and the difference in evaporation amount between the central portion 22 and the peripheral portion 21 of the line-shaped liquid 2 is increased. Can do. Thereby, formation of the flow which carries a functional material to the peripheral part 21 can be accelerated | stimulated.

  Next, as shown in FIG. 3, a part of each thin wire 3 formed on the substrate 1 by each line-shaped liquid 2 is removed. The site | part shown with the broken line in FIG. 3 is shown.

  When a part of the thin wire 3 is removed, the remaining portion of the thin wire 3 that remains without being removed becomes a portion that is used as a functional thin wire. Here, with respect to each thin line 3, other portions are removed so that only the line segment 31 composed of one straight line on one side of the pair of parallel line segments 31, 31 is left. Thereby, four line segments 31 remain side by side on the substrate 1.

  As a method of removing a part of the thin wire 3, a method of irradiating an energy beam such as a laser beam or a chemical for chemically etching is possible because a part of the thin wire 3 can be easily and selectively removed. The method by etching is mentioned. In particular, the method of irradiating with energy rays can remove pinpoints by selectively irradiating a part of the thin wires 3 to be removed, thereby greatly reducing the time required for the removal process. This is preferable because the tact time can be shortened.

  By removing a part of the thin wire 3, a plurality of parallel functional materials are included on the base material 1 by the four line segments 31 that remain without being removed, as shown in FIG. 4. A functional thin line pattern in which four functional thin lines 4 are arranged at equal intervals is formed.

  In this functional fine line pattern, the arrangement interval L2 along the X direction of the adjacent functional fine lines 4 and 4 is larger than the arrangement interval L1 of the adjacent line segments 31 and 31 shown in FIG. This arrangement interval L2 is determined by the arrangement interval of the line-shaped liquids 2 provided in parallel on the substrate 1. Therefore, by arbitrarily setting the arrangement interval of the line-shaped liquid 2, the arrangement interval L2 of the functional fine lines 4 and 4 constituting the functional fine-line pattern can be formed from one line-shaped liquid 2. Without being limited to the arrangement interval L1 of the two line segments 31, 31, it can be easily set to be wider than the arrangement interval L1.

  In general, the arrangement interval L1 between a pair of parallel line segments 31 and 31 of thin lines 3 formed from one line-shaped liquid 2 is limited to about 500 μm. As the line-shaped liquid 2 becomes wider, the moving distance of the functional material toward the peripheral edge 21 at the time of drying becomes longer, and the functional material is dried before reaching the peripheral edge 21. This is because it is difficult to stably deposit the functional material on 21. However, according to the present invention, the line-shaped liquid 2 does not need to be widened, and the functional thin wire 4 including the functional material can be stably formed.

  Moreover, since the part to be removed is only a part of each thin line 3, the area to be removed can be extremely small. For this reason, the tact time for forming the functional thin line pattern can be shortened, and the productivity can be improved.

  The functional thin line pattern shown in FIG. 4 has an arrangement interval L2 by leaving only the line segment 31 on the left side of the thin line 3 formed by the line-like liquids 2 arranged in parallel at equal intervals as shown in FIG. The four functional thin wires 4 are arranged in parallel at equal intervals.

  Here, since the line width of the functional thin wire 4 becomes extremely narrower than the width of the line-like liquid 2 due to the coffee stain phenomenon, for example, when the functional thin wire 4 is formed on the transparent substrate 1, the functionality is reduced. It is difficult to visually recognize the thin wire 4 and it becomes easy to ensure transparency. Further, even if the substrate 1 is opaque, the functional thin wire 4 on the surface may be visually recognized depending on how light is reflected. Even in this case, the functional thin wire 4 is visually recognized because it is extremely thin. It can be difficult. However, if the width of each functional thin wire 4 is made too thin, there is a possibility that a problem of disconnection may occur. Therefore, the functional thin wire 4 needs to have a certain thickness. Moreover, if the arrangement | positioning space | interval L2 of the adjacent functional fine wires 4 and 4 is enlarged too much, each of the functional thin wires 4 will be close to the state which exists in isolation on the base material 1, and will become easy to be visually recognized on the contrary.

  For this reason, in the present invention, attention is paid to the arrangement interval L2 of the functional thin wires 4 and 4 and the line width of each functional thin wire 4. That is, in the present invention, when the arrangement interval L2 of the functional thin wires 4 and 4 formed so as to be arranged in parallel on the substrate 1 is set to 300 μm or more and less than 750 μm, the line width of the functional thin wire 4 is 2 μm or more. When the distance L2 between the functional thin wires 4 and 4 is set to 750 μm or more and 2.5 mm or less, the width of the functional thin wire 4 is formed to be 2 μm or more and 5 μm or less. Thereby, the functional fine wire pattern which consists of the functional fine wire 4 which does not have the malfunction of a disconnection, and is hard to visually recognize on the base material 1 can be formed.

  If the arrangement interval L2 between the adjacent functional thin wires 4 and 4 is less than 300 μm, it is difficult to obtain a merit with respect to the case where each pair of parallel line segments 31 and 31 of the thin wires 3 is used as the functional thin wire. In addition, when the arrangement interval L2 exceeds 2.5 mm, even if the line width of the functional thin wire 4 is adjusted to be thin, the effect of making it difficult to visually recognize each of the functional thin wires 4 cannot be obtained sufficiently.

  Moreover, if the line width of the functional thin wire 4 is less than 2 μm, the functional thin wire 4 becomes too thin, and disconnection is likely to occur when stress is applied to the functional thin wire 4. When the line width exceeds 7 μm, the functional thin line 4 is easily visually recognized regardless of the arrangement interval L2.

  The arrangement interval L2 between the functional thin wires 4 and 4 is set by adjusting the interval between the line-shaped liquids 2 provided on the substrate 1 so as to be arranged in parallel. Moreover, although the line width of the functional thin wire 4 is set by the above-described condition adjustment at the time of drying, the line width of the functional thin wire 4 is more preferably any one of the following conditions or two or more It is adjusting so that it may become said range by employ | adopting conditions together.

  First, the first preferable condition is that the contact angle of the linear liquid 2 with respect to the substrate 1 is 10 ° or more and 30 ° or less, and droplets per pixel when the linear liquid 2 is applied on the substrate 1. The amount is set to 300 pl or less, and the solid content concentration of the liquid (ink) containing the functional material for forming the line-shaped liquid 2 is set to 0.1% or more. By applying the line-like liquid 2 on the substrate 1 under the above conditions and thereby forming the functional thin wire 4, the line width of the functional thin wire 4 is in the above range, specifically 7 μm or less or 5 μm. It can be easily adjusted to be as follows.

  When the contact angle is 10 ° or more, it is possible to prevent the ink from being too wet, to prevent the solid content accumulated in the form of parallel fine lines during drying of the ink from being broken, and to further stabilize the formation of the line. Furthermore, when the contact angle is 30 ° or less, it is possible to prevent the liquid from being excessively repelled on the base material, and it is possible to suitably form a desired line (line-shaped liquid). On the other hand, when the contact angle is less than 10 ° or exceeds 30 °, it is difficult to form the functional thin wire 4 having the line width in the above range even if the droplet amount and the solid content concentration satisfy the above conditions. . More preferably, the contact angle is 10 ° or more and 25 ° or less. The contact angle is a value measured based on JIS R 3257.

  When the amount of droplets per pixel exceeds 300 pl, the line-like liquid 2 becomes too wide, so that the functionality having a line width in the above range even if the contact angle and the solid content concentration satisfy the above conditions. It becomes difficult to form the thin wire 4 stably. More preferably, the amount of droplets per pixel is 30 pl or more and 200 pl or less.

  Note that a pixel is a minimum unit of a region on the substrate 1 that is filled with droplets ejected from the nozzles of the inkjet head in order to form the line-shaped liquid 2. When applying the line-shaped liquid 2 on the substrate 1, one pixel may be filled with one droplet of 300 pl or less, or may be filled with a plurality of droplets totaling 300 pl or less. Also good.

  When the solid content concentration is 0.1% or more, the thin wire 3 on which the functional material is deposited can be formed more stably. On the other hand, if the solid content concentration is less than 0.1%, it is difficult to form the functional thin wire 4 having a line width in the above range even if the contact angle and the droplet amount satisfy the above conditions. More preferably, the solid content concentration is 0.2% or more and 1% or less.

  Next, the second preferable condition is that when the line-shaped liquid 2 is dried, the temperature of the base material 1 is set to 60 ° C. or more and 85 ° C. or less and drying is performed by suction air.

  By drying with suction air, the gas evaporated from the line-shaped liquid 2 can be quickly removed from above the line-shaped liquid 2, and from the central portion 22 of the line-shaped liquid 2 (see FIG. 6B). The flow which carries a functional material to the peripheral part 21 is accelerated | stimulated. As a result, the filling density of the functional material in the peripheral portion 21 is increased, and the line width of the obtained functional thin wire 4 can be reduced. However, when the temperature of the base material 1 is less than 60 ° C., even if drying is performed with suction air, the evaporation of the line-shaped liquid 2 becomes insufficient, and it is difficult to form a flow toward the peripheral portion 21 of the functional material. For this reason, it becomes difficult to form the functional thin wire 4 whose line width is in the above range. On the other hand, if the temperature exceeds 85 ° C., the evaporation of the line-shaped liquid 2 is promoted too much, so that there is no difference in drying between the peripheral portion 21 and the central portion 22 of the line-shaped liquid 2, and the line width is also in the above range. It becomes difficult to form the functional thin wire 4. A more preferable temperature is 60 ° C. or higher and 70 ° C. or lower.

  Furthermore, the third preferable condition is that after the functional fine wire 4 is formed on the substrate 1, the surface of the functional fine wire 4 is oxidized by heat treatment at 80 ° C. or higher and 150 ° C. or lower in the atmosphere. It is.

  This oxidation treatment is, so to speak, a pretreatment for reducing the line width of the functional thin wire 4, and as a result of this oxidation treatment, as shown in FIG. 7, the edge 41 of the functional thin wire 4 (the shaded portion in FIG. 7). ) Is preferentially oxidized. This is because the edge portion 41 has a larger surface area per volume than the central portion 42 of the functional thin wire 4. The edge 41 of the oxidized functional thin wire 4 can be easily removed by post-processing, and the line width of the functional thin wire 4 is adjusted to be in the above range, specifically, 7 μm or less or 5 μm or less. Becomes easy. The processing width of the edge 41 to be oxidized can be adjusted according to the time of the oxidation treatment.

  If the heating temperature is less than 80 ° C., the oxidation may not proceed sufficiently, and if it exceeds 150 ° C., the center part of the unintended line may be oxidized or the base material may be whitened. More preferably, the heat treatment is performed at a heating temperature of 100 ° C. or higher and 140 ° C. or lower.

  A specific method for reducing the line width of the functional thin wire 4 after the oxidation treatment is to treat the oxidized functional thin wire 4 with an electrolyte solution to thereby treat the edge of the oxidized functional fine wire 4. A method of selectively removing 41 may be mentioned. By immersing the base material 1 having the oxidized functional thin wire 4 in the electrolyte solution, the line width of the functional thin wire 4 can be easily removed.

  The electrolyte solution is not particularly limited, and examples thereof include an aqueous copper sulfate solution. When the functional material is a conductive material, it is preferable to use a plating solution as the electrolyte solution. Simultaneously with the plating treatment (for example, copper plating treatment) for the functional thin wire 4, a treatment for reducing the line width of the functional thin wire 4 after the oxidation treatment can be performed. That is, when the functional thin wire 4 is plated after the oxidation treatment, the functional thin wire 4 is reduced in width by being treated with a plating solution that is an electrolyte solution. By plating the functional fine wire 4 using a conductive material as a functional material, the conductive performance can be enhanced by increasing the film thickness of the functional fine wire 4, and a wiring having a small electric resistance is formed. Can do. Details of the conductive material will be described later.

  When the functional thin wire 4 after the oxidation treatment is immersed in the plating solution and the plating treatment is performed, the central portion 42 in which the oxidation is relatively suppressed is well plated, but the edge portion 41 that has been preferentially oxidized. Since the conductivity is lower than that of the central portion 42, the plating does not proceed and is removed by the plating solution that is an electrolyte solution. Thereby, the line width of the functional thin wire 4 is reduced. The plating process width for the functional thin wire 4 and the removal amount of the edge 41 removed in the plating solution can be adjusted by the time of the plating process, and the line width of the functional thin wire 4 finally obtained by the plating process is adjusted. be able to.

  Further, when the functional material is a conductive material, after the oxidation treatment, the functional fine wire 4 is subjected to copper (Cu) plating treatment, and then subjected to copper etching treatment, thereby reducing the line width of the functional fine wire 4. Is also preferable.

  By performing copper plating on the functional thin wire 4 after the oxidation treatment, the film thickness of the functional thin wire 4 is increased. Next, when a copper etching process is performed, the copper layer plated on the surface of the functional thin wire 4 is removed. At this time, the edge 41 of the functional thin wire 4 has a lower conductivity than the central portion 42, so that it is difficult to be plated during the copper plating process and is easily etched during the copper etching. For this reason, the edge part 41 is removed preferentially rather than the center part 42. Thereby, the line width of the functional thin wire 4 can be reduced.

  Furthermore, it is also preferable that the functional fine wire 4 after the oxidation treatment is subjected to nickel (Ni) plating treatment. By performing the nickel plating process, the functional fine wire 4 can be reduced in visibility. This is because the nickel-plated surface has a color showing low visibility compared to copper. The nickel plating treatment may be performed by forming a layer of nickel alone on the functional thin wire 4 or by applying the copper plating treatment on the functional thin wire 4 after forming a copper layer. A nickel layer may be further formed on the copper layer.

  In the embodiment described above, a comb-like functional fine line pattern in which a plurality of functional fine lines 4 arranged in parallel in one direction on the substrate 1 is used. However, the functional fine line pattern according to the present invention is not limited thereto. Absent. For example, a lattice-like functional fine line pattern may be formed on the substrate 1.

  8 to 11 are plan views for explaining an example of a forming method in the case of forming a lattice-like functional thin line pattern. Since the site | part of the same code | symbol as FIGS. 1-4 has shown the site | part of the same structure, those description uses the said description and abbreviate | omits here.

  First, as shown in FIG. 8, a plurality of line-shaped liquids 2A are formed on a substrate 1 by applying a plurality of line-shaped liquids 2A containing a functional material in parallel. Here, the plurality of line-shaped liquids 2 </ b> A are formed so as to be inclined at an angle of 45 ° with respect to the Y direction of the substrate 1.

  Thereafter, as in the case of the above-described embodiment, with the drying of the line-shaped liquid 2A, a functional material is selectively deposited on the peripheral portion 21 of each line-shaped liquid 2A by the coffee stain phenomenon. As a result, an aggregate of a plurality of parallel thin wires 3A having a pair of two parallel line segments 31, 31 is formed.

  Next, as shown in FIG. 9, a plurality of line-shaped liquids 2B are formed by applying a plurality of line-shaped liquids 2B containing functional materials in parallel on the plurality of fine wires 3A arranged in parallel. The plurality of line-shaped liquids 2B are formed so as to incline at an angle of 45 ° on the opposite side to the thin line 3A with respect to the Y direction of the substrate 1, and intersect with the previously formed fine line 3A. Yes.

  Thereafter, with the drying of the line-shaped liquid 2B as described above, a functional material is selectively deposited on the peripheral edge 21 of each line-shaped liquid 2B by the coffee stain phenomenon. As a result, as shown in FIG. 10, an assembly of a plurality of parallel thin wires 3B having a set of two parallel line segments 31 and 31 is formed. The fine wire 3A and the fine wire 3B formed thereby are orthogonal to each other.

  Next, as shown in FIG. 11, a part of each thin wire 3 </ b> A, 3 </ b> B on the substrate 1 is removed in the same manner as in the above-described embodiment. FIG. 11 shows a portion where the portion indicated by a broken line is removed.

  Here, when removing a part of each of the thin wires 3A and 3B, the remaining portions of the thin wires 3A and 3B (functional thin wires 4A and 4B in FIG. 11) It removes so that it may not be disconnected at the intersection P with a part (part shown with the broken line in FIG. 11). As a result, a lattice-like functional thin line pattern in which the functional thin lines 4A and 4B reliably intersect at the intersections is formed by the portions of the plurality of thin lines 3A and 3B that remain without being removed.

  Thereby, the arrangement interval L12 of the functional thin wires 4A and 4A becomes larger than the arrangement interval L11 of the line segments 31 and 31 constituting the thin line 3A shown in FIG. The arrangement interval of the functional thin wires 4B and 4B is the same. Therefore, in this embodiment, similarly to the above, the arrangement intervals of the functional thin wires 4A, 4A, 4B, and 4B are set to one by setting the arrangement intervals of the line-like liquids 2A and 2B arbitrarily. The tact time for forming a functional thin line pattern can be freely set so as to be larger than the arrangement interval of the two line segments 31, 31 formed from the line liquids 2A, 2B. Can be greatly shortened, and productivity can be improved.

  For example, when the functional material is a conductive material and the functional thin wires 4A and 4B are used as wirings, a lattice pattern is formed that is reliably electrically connected at the intersection of the functional thin wires 4A and 4B. It is possible.

  Even in the case of forming such a lattice-like functional thin line pattern, the arrangement interval L12 of each functional thin line 4A, 4A, 4B, 4B and the line width of each functional thin line 4A, 4B are completely different from those in the above embodiment. By defining similarly, the same effect as the above-mentioned embodiment can be acquired.

  Next, the conductive material will be described. Preferred examples of the conductive material include conductive fine particles and conductive polymers.

  The conductive fine particles are not particularly limited, but Au, Pt, Ag, Cu, Ni, Cr, Rh, Pd, Zn, Co, Mo, Ru, W, Os, Ir, Fe, Mn, Ge, Sn, Ga, Fine particles such as In can be preferably exemplified, and among them, it is preferable to use fine metal particles such as Au, Ag, and Cu because they can form thin wires having low electric resistance and strong against corrosion. From the viewpoint of cost and stability, metal fine particles containing Ag are most preferable. The average particle diameter of these metal fine particles is preferably in the range of 1 to 100 nm, more preferably in the range of 3 to 50 nm. The average particle diameter is a volume average particle diameter, and can be measured with a Zetasizer 1000HS manufactured by Malvern.

  It is also preferable to use carbon fine particles as the conductive fine particles. Preferable examples of the carbon fine particles include graphite fine particles, carbon nanotubes, fullerenes and the like.

  Although it does not specifically limit as a conductive polymer, (pi) conjugated system conductive polymer can be mentioned preferably. Examples of the π-conjugated conductive polymer include polythiophenes, polypyrroles, polyindoles, polycarbazoles, polyanilines, polyacetylenes, polyfurans, polyparaphenylenes, polyparaphenylene vinylenes, polyparaphenylene sulfide. Chain conductive polymers such as polyazenes, polyazulenes, polyisothianaphthenes, and polythiazyl compounds can be used. Among these, polythiophenes and polyanilines are preferable in that high conductivity is obtained, and polyethylenedioxythiophene is most preferable.

  More preferably, the conductive polymer comprises the above-described π-conjugated conductive polymer and a polyanion. Such a conductive polymer can be easily produced by chemical oxidative polymerization of a precursor monomer that forms a π-conjugated conductive polymer in the presence of an appropriate oxidizing agent, an oxidation catalyst, and a polyanion.

  A commercially available material can also be preferably used for the conductive polymer. For example, conductive polymers consisting of poly (3,4-ethylenedioxythiophene) and polystyrene sulfonic acid are commercially available from HCStarck as CLEVIOS series, from Aldrich as PEDOT-PASS483095, 560598, from Nagase Chemtex as Denatron series Has been. Polyaniline is commercially available from Nissan Chemical as the ORMECON series.

  As the liquid containing the functional material, for example, one kind or a combination of two or more kinds such as water and an organic solvent can be used. The organic solvent is not particularly limited. For example, alcohols such as 1,2-hexanediol, 2-methyl-2,4-pentanediol, 1,3-butanediol, 1,4-butanediol, propylene glycol, Examples include 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.

  Further, the liquid containing the functional material may contain various additives such as a surfactant as long as the effects of the present invention are not impaired. By using a surfactant, for example, when the line-like liquid 2 is formed on the substrate 1 using an inkjet head, it is possible to stabilize the discharge by adjusting the surface tension etc. become. The surfactant is not particularly limited, but a silicon surfactant or the like can be used. Silicone surfactants are those obtained by modifying the side chain or terminal of dimethylpolysiloxane with polyether, such as KF-351A and KF-642 manufactured by Shin-Etsu Chemical, BYK347 and BYK348 manufactured by Big Chemie. ing. The content of the surfactant is preferably 1% by weight or less with respect to the total amount of the line liquid 2.

  In the present invention, the functional fine wire pattern can be used for various electric devices by, for example, providing the functional fine wire 4 with electrical conductivity to form electric wiring. As an electrical device, for example, as a transparent electrode for various types of displays such as liquid crystal, plasma, organic electroluminescence, field emission, etc., or as a touch panel, mobile phone, electronic paper, various solar cells, various electroluminescence dimming elements, etc. It can use suitably as a transparent electrode used. It is particularly preferable to use a substrate with a transparent conductive film as a touch panel sensor for electronic devices such as smartphones and tablet terminals.

  Examples of the present invention will be described below, but the present invention is not limited to these examples.

  First, according to Reference Examples 1 to 6, the influence of the arrangement interval and the line width of the thin lines on the light transmittance and the low visibility of the thin lines will be verified.

(Reference Example 1)
A polyethylene terephthalate (PET) film (thickness 50 μm) is used as a base material, an ink jet head (piezo head manufactured by Konica Minolta, standard droplet volume 30 pl) is used on the base material, and silver is used as a functional material. By applying the ink containing the nanoparticles in a line shape, a collection of line liquids arranged in parallel at equal intervals was formed.
When forming the line-shaped liquid, the number of applied droplets per pixel is 2 [dpd], the applied amount of droplets per pixel is 60 [pl], and the solid content concentration in the ink is 0.690 [wt%]. Set.
Then, with drying of the line-shaped liquid, silver nanoparticles in each line-shaped liquid were deposited on the peripheral edge portion to form an aggregate A-1 of thin lines having a set of two line segments parallel to each other.
The arrangement interval of the two pairs of thin wires obtained was 100 μm. Here, the application | coating space | interval of the line-shaped liquid was adjusted so that the space | interval of adjacent thin wires might also be 100 micrometers. The line width of the obtained thin line was 2 [μm].
A functional fine line pattern was obtained as described above.

(Reference Example 2)
In Reference Example 1, when forming a line-shaped liquid, the number of applied droplets per pixel is 4 [dpd], the applied amount of droplets per pixel is 120 [pl], and the solid content concentration in the ink is 0.345. [Wt%] was set.
The arrangement interval of the two pairs of thin wires obtained was 140 μm. Here, the application interval of the line-shaped liquid was adjusted so that the interval between adjacent thin wires was 140 μm. The line width of the obtained thin line was 4 [μm].

(Reference Example 3)
In Reference Example 1, when forming a line-shaped liquid, the number of applied droplets per pixel is 6 [dpd], the applied amount of droplets per pixel is 180 [pl], and the solid content concentration in the ink is 0.23. [Wt%] was set.
The arrangement interval of the two pairs of thin lines obtained was 170 μm. Here, the application | coating space | interval of a line-shaped liquid was adjusted so that the space | interval of adjacent thin wires might also be 170 micrometers. Moreover, the line width of the obtained thin wire | line was 5 [micrometers].

(Reference Example 4)
In Reference Example 1, when forming a line-shaped liquid, the number of applied droplets per pixel is 10 [dpd], the applied amount of droplets per pixel is 300 [pl], and the solid content concentration in the ink is 0.138. [Wt%] was set.
The arrangement interval between the two pairs of thin wires obtained was 274 μm. Here, the application interval of the line-shaped liquid was adjusted so that the interval between adjacent thin wires was also 274 μm. Further, the line width of the obtained thin line was 7 [μm].

(Reference Example 5)
In Reference Example 1, when forming a line-shaped liquid, the number of applied droplets per pixel is 30 [dpd], the applied amount of droplets per pixel is 900 [pl], and the solid content concentration in the ink is 0.046. [Wt%] was set.
The arrangement interval of the pair of two thin wires obtained was 400 μm. Here, the application interval of the line-shaped liquid was adjusted so that the interval between adjacent fine lines was also 400 μm. The line width of the obtained thin line was 10 [μm].

(Reference Example 6)
In Reference Example 1, when forming a line-shaped liquid, the number of applied droplets per pixel is 80 [dpd], the applied amount of droplets per pixel is 2400 [pl], and the solid content concentration in the ink is 0.017. [Wt%] was set.
The arrangement interval between the two pairs of thin wires obtained was 650 μm. Here, the application | coating space | interval of the line-shaped liquid was adjusted so that the space | interval of adjacent thin wires might also be 650 micrometers. Further, the line width of the obtained thin line was 15 [μm].

<Evaluation method>
(1) Light transmittance The total light transmittance of the functional fine line pattern was measured using AUTOMATIC HAZEMETER (MODEL TC-H III DP) manufactured by Tokyo Denshoku. In addition, it corrected using the base material (film) without a pattern, and measured it as the total light transmittance of the created pattern. Based on the measured value, light transmittance was evaluated according to the following evaluation criteria.
[Evaluation criteria]
A: Total light transmittance is 92% or more B: Total light transmittance is less than 92%

(2) Low visibility of fine lines Based on the result of visual observation of a substrate on which a functional fine line pattern was formed from a position 50 cm away on a light table, low visibility was evaluated according to the following evaluation criteria.
[Evaluation criteria]
A: A thin line cannot be visually recognized. B: A thin line can be visually recognized.

<Evaluation>
As shown in Table 1, when two thin lines are formed from a line-shaped liquid, if the line width of the thin lines is reduced to improve the low visibility of the thin lines, the arrangement interval of the thin lines cannot be increased, and the light It becomes difficult to obtain permeability. On the other hand, if an attempt is made to increase the light transmission by increasing the arrangement interval of the thin lines, the line width of the thin lines cannot be reduced, and it becomes difficult to obtain low visibility. Therefore, room for further improvement is found from the viewpoint of achieving both light transmittance and low visibility.

Example 1
A polyethylene terephthalate (PET) film (thickness 50 μm) is used as a base material, an ink jet head (piezo head manufactured by Konica Minolta, standard droplet volume 30 pl) is used on the base material, and silver is used as a functional material. By applying the ink containing the nanoparticles in a line shape, a collection of line liquids arranged in parallel at equal intervals was formed.
When forming the line-shaped liquid, the number of applied droplets per pixel is 2 [dpd], the applied amount of droplets per pixel is 60 [pl], and the solid content concentration in the ink is 0.690 [wt%]. Set.
Thereafter, as the line-shaped liquid is dried, as shown in FIG. 14A, silver nanoparticles in each line-shaped liquid are deposited on the peripheral edge, and the fine lines having a set of two parallel line segments are formed. Aggregate A-1 was formed.
The arrangement interval of the two pairs of thin wires obtained was 100 μm. The line width of the obtained thin line was 2 [μm].
By using a fiber laser (wavelength 1 μm, spot diameter 30 μm) for this assembly A-1, as shown in FIG. 14B, only the right side of each thin line is irradiated with laser light. Part of the fine line was removed. As a result, an assembly B-1 of functional fine wires was formed by the line segments remaining without being removed.

  The functional thin line pattern in which the arrangement interval of the adjacent functional fine lines obtained by this is 650 μm, and the arrangement interval of the plurality of functional fine lines is larger than the line segment of the fine lines formed from the line-shaped liquid. I was able to form.

(Example 2)
In Example 1, the solid content concentration in the ink was set to 0.173 [wt%] when forming the line liquid. The obtained thin wire had a line width of 5 [μm]. Further, by removing a part of the fine line, the arrangement interval of the remaining part of the fine line was set to be 650 μm.

(Example 3)
In Example 1, the solid content concentration in the ink was set to 0.173 [wt%] when forming the line liquid. The obtained thin wire had a line width of 5 [μm]. Further, by removing a part of the fine line, the arrangement interval of the remaining part of the fine line was set to 350 μm.

Example 4
In Example 1, the solid content concentration in the ink was set to 0.173 [wt%] when forming the line liquid. The obtained thin wire had a line width of 5 [μm]. Further, by removing a part of the fine line, the arrangement interval of the remaining part of the fine line was set to 700 μm.

(Comparative Example 1)
In Example 1, the solid content concentration in the ink was set to 0.052 [wt%] when forming the line liquid. The obtained thin wire had a line width of 1.5 [μm]. Further, by removing a part of the fine line, the arrangement interval of the remaining part of the fine line was set to be 650 μm.

(Comparative Example 2)
In Example 1, the solid content concentration in the ink was set to 0.276 [wt%] when forming the line liquid. The line width of the obtained thin line was 8 [μm]. Further, by removing a part of the fine line, the arrangement interval of the remaining part of the fine line was set to be 650 μm.

(Example 5)
In Example 1, the solid content concentration in the ink was set to 0.173 [wt%] when forming the line liquid. The obtained thin wire had a line width of 5 [μm]. Further, by removing a part of the fine line, the arrangement interval of the remaining part of the fine line was set to 750 μm.

(Example 6)
In Example 1, the solid content concentration in the ink was set to 0.173 [wt%] when forming the line liquid. The obtained thin wire had a line width of 5 [μm]. Further, by removing a part of the fine line, the arrangement interval of the remaining part of the fine line was set to 2000 μm.

(Example 7)
In Example 1, the solid content concentration in the ink was set to 0.173 [wt%] when forming the line liquid. The obtained thin wire had a line width of 5 [μm]. Further, by removing a part of the fine line, the arrangement interval of the remaining part of the fine line was set to 2500 μm.

(Comparative Example 3)
In Example 1, the solid content concentration in the ink was set to 0.052 [wt%] when forming the line liquid. The obtained thin wire had a line width of 1.5 [μm]. Further, by removing a part of the fine line, the arrangement interval of the remaining part of the fine line was set to 750 μm.

(Comparative Example 4)
In Example 1, the solid content concentration in the ink was set to 0.207 [wt%] when forming the line liquid. The line width of the obtained thin line was 6 [μm]. Further, by removing a part of the fine line, the arrangement interval of the remaining part of the fine line was set to 750 μm.

  Table 2 shows the results of evaluation of the functional thin line patterns obtained in the examples and comparative examples in the same manner as in the reference examples.

<Evaluation>
As shown in Table 2, (1) when the arrangement interval of the functional thin lines is set to 300 μm or more and less than 750 μm, the line width of the functional thin lines is set to 2 μm or more and 7 μm or less; and (2) It can be seen that when the arrangement interval is set to 750 μm or more and 2.5 mm or less, the light transmission and low visibility can be achieved by setting the width of the functional thin wire to 2 μm or more and 5 μm or less.

  About the comparative examples 1 and 3, although light transmittance and low visibility can be made compatible, it disconnected by stress at the time of drying or a post process (plating), and the conduction failure (disconnection failure) had arisen.

1: Substrate 2, 2A, 2B: Line-shaped liquid 21: Peripheral part 22: Center part 3, 3A, 3B: Fine line 31: Line segment 4, 4A, 4B: Functional fine line 41: Edge part 42: Center part d :Dot

Claims (11)

A plurality of line-shaped liquids containing functional materials are provided on the substrate so as not to overlap each other.
Next, as the line-shaped liquid is dried, the functional material is selectively deposited on the periphery of the line-shaped liquid, so that the line-shaped liquid has two pairs of parallel line segments. Each thin line is formed,
Next, by removing a part of each of the thin lines and forming functional thin lines by the remaining portions of the thin lines, the arrangement intervals of the plurality of functional thin lines are such that the thin lines formed from the line-shaped liquid A method of forming a functional fine line pattern that is larger than the arrangement interval of the two line segments that are parallel to each other.
When the arrangement interval of the functional thin wires is 300 μm or more and less than 750 μm, the line width of the functional thin wires is 2 μm or more and 7 μm or less,
A method for forming a functional fine line pattern, wherein when the arrangement interval of the functional fine lines is 750 μm or more and 2.5 mm or less, the line width of the functional fine lines is 2 μm or more and 5 μm or less. The contact angle of the linear liquid with respect to the substrate is 10 ° or more and 30 ° or less,
The amount of liquid droplets per pixel when applying the line-shaped liquid on the substrate is 300 pl or less,
The method for forming a functional fine line pattern according to claim 1, wherein the solid content concentration of the liquid containing the functional material for forming the linear liquid is 0.1% or more.   The method for forming a functional fine line pattern according to claim 1 or 2, wherein the drying of the linear liquid is performed by setting the temperature of the base material to 60 ° C or higher and 85 ° C or lower and using a suction air.   The function according to claim 1, 2, or 3, wherein the surface of the functional thin wire is oxidized by heat treatment at 80 ° C or higher and 150 ° C or lower after forming the functional thin wire on the substrate. Of forming a fine thin line pattern.   5. The method of forming a functional fine line pattern according to claim 4, wherein a line width of the functional fine line is reduced by treating with an electrolyte solution after the oxidation treatment. The functional material is a conductive material,
6. The method of forming a functional fine line pattern according to claim 5, wherein, after the oxidation treatment, when the functional fine line is plated, the functional fine line is reduced in width by treating with a plating solution that is an electrolyte solution.   The method for forming a functional fine line pattern according to claim 6, wherein the plating process is a copper plating process. The functional material is a conductive material,
5. The method of forming a functional fine line pattern according to claim 4, wherein after the oxidation treatment, the functional fine line is subjected to copper plating treatment and then subjected to copper etching treatment to reduce a line width of the functional fine line.   The method for forming a functional fine wire pattern according to any one of claims 5 to 8, wherein the functional fine wire is subjected to nickel plating after the oxidation treatment. A functional fine line pattern in which a plurality of functional fine lines containing a functional material are arranged in parallel on a base material,
The arrangement interval of the functional thin wires is 300 μm or more and less than 750 μm,
A functional fine line pattern in which a line width of the functional fine line is 2 μm or more and 7 μm or less. A functional fine line pattern in which a plurality of functional fine lines containing a functional material are arranged in parallel on a base material,
The arrangement interval of the functional thin wires is 750 μm or more and 2.5 mm or less,
A functional fine line pattern in which a line width of the functional fine line is 2 μm or more and 5 μm or less.

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