JP2014176823A - Pattern formation method, and substrate employing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a patterning method which enables a stable pattern to be formed only by a printing process without causing a pattern failure such as liquid pool in a case where the physical properties of liquid to be applied are not suitable for coating in patterning by printing.SOLUTION: A pattern formation method comprises a first applying process of applying liquid adjusted to a physical property value suitable for patterning to a substrate, a first drying process of drying the liquid applied in the first coating process, a second applying process of executing patterning again so as to trace a part patterned in the first coating process, and a second drying process of drying the liquid applied in the second applying process.

Description

  The present invention relates to a pattern forming method for forming a desired pattern on a substrate by applying a liquid onto the substrate, and a substrate based thereon.

  In recent years, a method for forming patterning on a substrate by a printing technique such as flexographic printing, gravure printing, and ink jet has been studied extensively. As a method of creating a pattern, for example, in the case of conventional lithography, there are a large number of steps such as (Step 1) film formation, (Step 2) photolithography, (Step 3) etching, (Step 4) resist stripping step, and etching and Since the material removed in the resist stripping process is also used, the cost increases. If this can be replaced by printing, the process can be shortened, and the cost can be reduced because the material is used only for the pattern portion.

  However, in the case of patterning on a substrate by a printing method, the liquid flows until after the patterning due to non-uniformity in how the liquid spreads after being transferred to the substrate or a repelling phenomenon called dewetting. Precise patterning on a flat substrate is difficult. A method for controlling the flow is being sought.

  Although there is a method of patterning the lowered surface by irradiating UV light onto the surface of the substrate to which the liquid crystallinity is imparted to selectively reduce the liquid crystallinity, a photomask required for a photolithographic method using UV light Is expensive and disadvantageous in terms of cost.

  In Patent Document 1, a hydrophilic pattern is created in advance by irradiating a water-repellent processed water-repellent surface with an ultraviolet laser beam, and a precise pattern is formed by patterning a coating liquid on the hydrophilic pattern. Has been proposed.

  However, in the above method, the liquid repellent material is applied to the entire surface and then the process of removing only the patterning portion is performed. Therefore, the liquid repellent material is required even in the unnecessary portion and the portion to be removed, which increases the material cost. . Furthermore, since equipment for irradiating a laser beam is required separately from the coating equipment, the cost increases.

  Patent Document 2 proposes a method of controlling the wetting and spreading of the dropped liquid material by forming an indent (notch) region by the indent region.

  However, the above method requires a process for forming an indent on the substrate and cannot be completed by a simple printing process alone. Therefore, the cost increases due to the installation of equipment for forming the indent.

Japanese Patent Laid-Open No. 2004-200244 Japanese Patent No. 4917735

  When a coating liquid is to be patterned on a substrate by a printing process, if the liquid has a low viscosity, the liquid often moves and the coating film pattern tends to become unstable, and problems such as local liquid accumulation tend to occur. On the other hand, when the viscosity is too high, the liquid is difficult to be smooth, so that the shape of the liquid at the time of patterning tends to remain as it is, and the shape after application becomes distorted. In order to solve such problems, there is a method of creating a hydrophilic surface along the shape of the part to be patterned by photolithography, etc., but a large amount of water-repellent material is required. As a result, it is necessary to introduce equipment for patterning, which increases the cost. Therefore, in order to avoid these costs, when patterning is performed only in the printing process, it is necessary to adjust the physical properties of the liquid to be optimal in the printing process in the conventional method. However, it is difficult to achieve both material distribution necessary for expressing desired functionality and viscosity suitable for patterning. For example, when a thickener is mixed in the coating liquid to adjust the viscosity, the applied layer Problems such as deterioration in functionality that should be exhibited.

  The present invention has been made in view of such circumstances, and provides a coating film pattern forming method that improves the stability of patterning and can be stably applied when a low viscosity liquid is used. With the goal.

  In order to solve the above problems, the invention according to claim 1 of the present invention is to dry the liquid applied in the first application process and the first application process with a liquid adjusted to a physical property value suitable for patterning on the substrate. A first drying step to be performed, a second coating step in which patterning is performed again while tracing a portion patterned in the first coating step, and a second coating step in which the liquid applied in the second coating step is dried. A pattern forming method characterized by the above.

  In the above method, first, in the first coating step, a coating liquid having liquid properties that can realize a desired patterning shape is applied and dried. At this time, the liquid to be applied may be any liquid that does not hinder the functionality of the coating film formed by drying in the second coating process.

  Next, in the second coating step, coating is performed so as to trace the patterning shape applied in the first coating step. At this time, since the patterning shape formed in the first application step exists, the liquid spreads along this shape. In order to avoid problems such as non-uniform wetting and spreading, liquid accumulation, and repelling that occur when a liquid is directly applied on a substrate, the first application step can be performed without adjusting the application liquid to physical properties suitable for pattern application. A similar pattern can be applied.

  As a result, only a coating apparatus is required for patterning, and since it is not necessary to perform coating other than the patterning portion, less material is used, and a pattern is formed with an advantage in terms of cost compared to photolithography. be able to.

  The invention according to claim 2 of the present invention is characterized in that the coating liquid applied in the first coating step is a coating liquid different in concentration from the coating liquid applied in the second coating step. This is a pattern forming method.

  By making the liquid applied in the first application process the same composition that differs only in concentration from the liquid applied in the second application process, a pattern can be formed without any loss of functionality.

  The invention according to claim 3 of the present invention is the pattern forming method according to claim 1 or 2, wherein the method of applying the coating liquid to the substrate is a relief printing method.

  The invention according to claim 4 of the present invention is an organic EL display substrate manufactured by the pattern forming method according to any one of claims 1 to 3.

  According to the present invention, it is possible to perform patterning without adjusting physical properties, and to perform high-precision patterning without using a special apparatus other than the coating apparatus or forming a liquid repellent layer on the coating surface. Therefore, material costs and process costs can be reduced.

Sectional drawing at the time of apply | coating a 1st coating liquid on a board | substrate. Sectional drawing at the time of drying the 1st coating liquid on a board | substrate and creating the 1st coating layer. Sectional drawing at the time of apply | coating a 2nd coating liquid on the 1st application layer. Cross-sectional film at the time when the second coating liquid is dried and a functional film is formed. Schematic which shows the application state when the 2nd coating liquid can be stably apply | coated by apply | coating on a 1st application layer. Schematic which shows the state which has been patterned by the unstable shape because the 2nd coating liquid was apply | coated without apply | coating a 1st application layer. 1 is a schematic cross-sectional view showing an example of a relief printing press according to an embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  A small amount of the first coating solution 2 is applied to the substrate 1 to form a pattern as shown in FIG. At this time, the first coating liquid needs to adjust physical properties such as viscosity and surface tension in order to correctly form a desired pattern. However, since the amount to be applied itself may be very small, the physical property adjustment by an additive such as a thickener or a surfactant can be performed as long as the second coating layer 5 does not impair the functionality.

  Further, the first coating liquid 2 is dried to form a first coating layer 3 as shown in FIG. Since the first coating liquid 2 may be a trace amount as long as a desired pattern can be formed, the drying process can be shortened.

  Further, the second coating solution 4 is applied on the first coating layer 3. At this time, since the boundary between the first coating layer 3 and the substrate 1 functions in the same manner as a defect or a groove on the substrate, the contact line of the second coating liquid 4 is pinned at the boundary surface. Thereby, as shown in FIG. 3, the pattern similar to the 1st application layer formed in advance can be created easily.

  Furthermore, the pattern of the 2nd coating layer 5 which expresses a desired function is created as shown in FIG. 4 by drying the 2nd coating liquid 4. As shown in FIG.

  Through such a process, a normal pattern in which local deformation or the like as shown in FIG. 5 does not occur can be formed.

  If the first coating layer is not formed and the physical property adjustment suitable for coating is not performed, an abnormal coating film with local deformation as shown in FIG. 6 may be formed.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the technical scope of the present invention is not limited to these examples.

<Example>
Using the relief printing press 100 shown in FIG. 6, first, an anilox having a small cell capacity is used to apply a small amount of ink as a first application liquid on a glass substrate, and after drying, the concentration is different using an anilox having a large cell capacity. A pattern was created by applying and drying ink as a second coating solution.

  The ink liquid used as the first coating liquid uses a light emitting material made of a polyfluorene derivative as a polymer, the ink solvent composition is 89.0% by weight of xylene, 10.0% by weight of cyclohexylbenzene, and 1. The viscosity was adjusted to 0% by weight and adjusted to a viscosity suitable for coating by adding a fatty acid amide wax as a thickener.

  The ink liquid used as the second coating liquid was one that did not use a thickener from the first coating liquid.

  With the above method, a normal pattern as shown in FIG. 5 was printed on the glass surface.

<Comparative example>
The pattern was formed using the same method and the same ink liquid as in Example 1, but the first coating liquid 2 was not applied and printing was performed only with the second coating liquid 4.

  As a result, a puddle was scattered in the applied pattern, and an abnormal application pattern as shown in the uppermost pattern in FIG. 6 was printed.

DESCRIPTION OF SYMBOLS 1 ... Substrate 2 ... 1st coating liquid 3 ... 1st coating layer 4 ... 2nd coating liquid 5 ... 2nd coating layer 10 ... Normal coating film 11 ... Abnormal Coating film 100 ... letterpress printing machine

Claims (4)

  A first coating step with a liquid adjusted to a physical property value suitable for patterning on the substrate, a first drying step for drying the liquid applied in the first coating step, and a portion patterned in the first coating step. A pattern forming method comprising: a second application step of performing patterning again; and a second application step of drying the liquid applied in the second application step.   2. The pattern forming method according to claim 1, wherein the coating liquid applied in the first application process is a coating liquid that differs only in concentration from the coating liquid applied in the second application process.   The pattern forming method according to claim 1 or 2, wherein a method of applying the coating liquid in the first application step and the second application step to the substrate is a relief printing method.   An organic EL display substrate manufactured by the pattern forming method according to claim 1.

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