JP2015220179A - Method of manufacturing functional film, organic el functional film, organic solar cell functional film, organic semiconductor functional film, organic el element, organic solar cell element, organic semiconductor element, illuminating device, and display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a functional film capable of suppressing film thickness irregularity of the functional film, and of preventing occurrence of light emission irregularity of the functional film in a case where a coating head is made to scan one coating region several times to form the functional film.SOLUTION: A method of manufacturing a functional film includes: a first coating step of making a coating head filled with ink relatively scan a substrate, and discharging the ink from a plurality of nozzles of the coating head to a part of one sectioned region to form a first coating region; and a second coating step of making the coating head relatively scan the substrate in parallel with a scanning path of the coating head in the first coating step so that a part of the scanning range is overlapped, and discharging the ink to at least a part of the remaining part of the one sectioned region to form a second coating region. Discharge amounts of the ink in the first coating step and the second coating step are adjusted.

Description

  The present invention relates to a method for producing a functional film by scanning the coating head a plurality of times, an organic EL functional film produced by the production method, an organic solar cell functional film, an organic semiconductor functional film, and an organic comprising these functional films. The present invention relates to an EL element, an organic solar cell element, an organic semiconductor element, a lighting device, and a display device.

  In the manufacture of an organic EL display panel, each pixel is partitioned by a partition called a bank, and a coating liquid (ink) for forming an organic functional layer of the organic EL element is applied to the minute area in the bank by an inkjet method. In general, a method of forming an organic functional layer in each minute region partitioned by the bank is generally used. For example, Patent Document 1 discloses a technique for forming an organic functional layer by ejecting ink droplets containing an organic light-emitting material to a predetermined partition region of a display substrate using an inkjet device. Yes.

  In recent years, large-scale display panels have been actively manufactured and researched. In such large displays, the coating area on the substrate is larger than the width of the coating head of the inkjet apparatus (the area where coating can be performed once). In such a case, it is necessary to form the organic functional layer by scanning the coating head a plurality of times.

  In addition, in an organic EL lighting panel that is an illumination using an organic EL element, a coating area on a substrate differs from an organic EL display panel in which the width of a coating area partitioned by a bank is about several microns to several hundred microns. Is several centimeters to several tens of centimeters. Accordingly, also in the manufacture of the organic EL lighting panel, the width of the coating region on the substrate is wider than the width of the coating head of the ink jet device as in the case of the large display as described above. It is necessary to form an organic functional layer.

  In the case where the organic functional layer is formed by scanning the coating head a plurality of times, the organic functional layer formed by the first scanning of the coating head and the organic functional layer formed by the second scanning. There was a problem that uneven light emission occurred at the boundary. This is because the ink applied by the first scan flows before the second scan is performed, the ink applied by the first scan, and the ink applied by the second scan. This is because unevenness occurs at the boundary between the two organic functional layers due to the difference in the dry state and the like. That is, there is a problem that unevenness in light emission is caused by unevenness in film thickness at the boundary between two organic functional layers. In response to such a problem, Patent Document 2 discloses a method of manufacturing a functional film for the purpose of suppressing film thickness unevenness at the boundary between the first application region and the second application region.

JP 2004-362818 A JP 2011-129337 A

  In the method for producing a functional film disclosed in Patent Document 2, the coating amount in the vicinity of the boundary between the first coating region and the second coating region is made smaller than the coating amount at the center of each coating region. . However, it is difficult to sufficiently suppress film thickness unevenness at the boundary between the two organic functional layers only by controlling the coating amount.

  The present invention has been made in view of such a problem, and the object of the present invention is to function in the case of forming a functional film by scanning the coating head a plurality of times with respect to one partitioned coating region. An object of the present invention is to provide a method of manufacturing a functional film that can sufficiently suppress unevenness in film thickness and sufficiently prevent occurrence of unevenness in light emission of the functional film.

  In addition, the present invention provides an organic EL functional film, an organic solar cell functional film, an organic semiconductor functional film, an organic EL element including these functional films, and an organic sun, which are manufactured by using the method for manufacturing the functional film. A battery element, an organic semiconductor element, a lighting device, and a display device are provided.

  In order to achieve the above-described object, a method for manufacturing a functional film according to the present invention is a method for manufacturing a functional film, in which a functional film is formed by applying ink in one region partitioned on the surface of a substrate. The coating head filled with the ink is scanned relative to the substrate, and the ink is ejected from a plurality of nozzles of the coating head to a part of the partitioned region. The coating head is scanned relative to the substrate so as to be parallel to the scanning path of the coating head in the first coating step and to partially overlap the scanning range. And a second application step of forming a second application region by discharging the ink to at least a part of the remaining part of the partitioned one region, and the first application step and the second application step. Corresponding to the overlapping scanning range in The total discharge amount per unit area of the ink in the overlapping application region of the substrate is −30 of the total discharge amount per unit area of the ink in the first application region and the second application region other than the overlap application region. The ink ejection amount in the first application step and the second application step is adjusted so that the amount falls within the range of% to + 30%.

  In the functional film manufacturing method described above, in each of the first application step and the second application step, the number of ejection points per unit area of the ink in the overlap application region is the first other than the overlap application region. The number may be smaller than the number of ejection points per unit area of the ink in the application region and the second application region. By doing in this way, the total ejection amount per unit area of the ink in the overlapping application region of the substrate corresponding to the overlapping scanning range in the first application step and the second application step is set to be other than the overlapping application region. In the first application region and the second application region, the ink can be reliably set within a range of −30% to + 30% of the total discharge amount per unit area, and the functional film thickness unevenness can be sufficiently obtained. It is possible to sufficiently suppress the occurrence of uneven light emission of the functional film.

  In any one of the functional film manufacturing methods described above, in each of the first application step and the second application step, a single ejection amount of the ink in the overlap application region may be the first amount other than the overlap application region. The amount of ink discharged in one application region and the second application region may be smaller than the single ejection amount. By doing in this way, the total ejection amount per unit area of the ink in the overlapping application region of the substrate corresponding to the overlapping scanning range in the first application step and the second application step is set to be other than the overlapping application region. In the first application region and the second application region, the ink can be reliably set within a range of −30% to + 30% of the total discharge amount per unit area, and the functional film thickness unevenness can be sufficiently obtained. It is possible to sufficiently suppress the occurrence of uneven light emission of the functional film.

  In any one of the functional film manufacturing methods described above, the plurality of nozzles are arranged in parallel at a constant pitch on the coating head, and three or more nozzles are overlapped in the second coating step. The scanning range may be scanned. Thus, when the number of nozzles for scanning in the overlapping scanning range is 3 or more, the film thickness unevenness of the functional film in the overlapping application region can be further suppressed, and the occurrence of uneven light emission of the functional film can be further prevented.

  In any one of the functional film manufacturing methods described above, the discharge amount per unit area of the ink in the overlapping application region may be increased in the second application step as compared to the first application step. In such a case, in the second application step, at least one of the number of ink discharge points in the overlapping application region and the amount of ink discharged from one nozzle at a time is calculated. It may be more than one coating step. As described above, when the discharge amount per unit area of the ink for the overlapping application region in the second application process is increased as compared with the first application process, the ink applied in the first application process is increased. , It is possible to suppress spreading to the second application region other than the overlapping application region, and it is possible to make the thickness of the functional film formed in one partitioned region more uniform.

  In any one of the functional film manufacturing methods described above, in each of the first coating step and the second coating step, the first coating region or the second coating region other than the overlapping coating region and the overlapping coating region Gradually, at least one of the number of ink ejection points and one ejection amount of the ink from one nozzle on the same scanning path from the boundary to the end of the overlapping application region. It may be reduced to. In this way, even in the overlapping application region, it is possible to form a shape that approximates the shape after the flow of the ejected ink when the ink is ejected in the first application step. By increasing the film thickness of the functional film in the overlapping application region by discharging ink in the application process, the film thickness of the functional film in the overlapping application region can be made more uniform.

  In any one of the functional film manufacturing methods described above, the ink discharge point in the overlap application region in the second application step may be different from the discharge point in the first application step, or in the overlap application region. The ink ejection point may be the same as the ejection point in the first application step. By doing in this way, the total ejection amount per unit area of the ink in the overlapping application region of the substrate corresponding to the overlapping scanning range in the first application step and the second application step is set to be other than the overlapping application region. In the first application region and the second application region, the ink can be reliably set within a range of −30% to + 30% of the total discharge amount per unit area, and the functional film thickness unevenness can be sufficiently obtained. It is possible to sufficiently suppress the occurrence of uneven light emission of the functional film.

  In any one of the functional film manufacturing methods described above, different coating heads may be used in the first coating step and the second coating step. If different coating heads are used in this way, the second coating process can be started without waiting for the end of the first coating process, and the manufacturing time and manufacturing cost of the functional film can be reduced.

  In any one of the functional film manufacturing methods described above, the first coating step and the second coating step are repeated using the same ink as the ink for the partitioned one region. A thickening step for increasing the thickness of the functional film in one region may be further included. By performing such a thickening step, an optimal functional film can be manufactured according to the intended use of the functional film and the required characteristics.

  In the functional film manufacturing method including the above-described thickening step, the thickening step is performed at a position that does not overlap the overlapping application region when the functional film is formed on the surface of the substrate in the thickening step. You may form the said overlap application | coating area | region in. By doing so, slight variations in the film thickness in the functional film formed on the substrate can be offset by slight variations in the film thickness in the functional film formed in the thickening step, and thus manufactured. Variations in the film thickness of the entire functional film can be further reduced.

  In any one of the functional film manufacturing methods including the thickening step described above, the ink discharge amount per unit area in the thickening step is a unit area when the functional film is formed on the surface of the substrate. The ink ejection amount may be smaller than the above. By doing in this way, the variation in the film thickness in the upper layer located on the exposed surface side of the functional film can be further reduced, and the flatness of the functional film in the uppermost layer (exposed surface) of the manufactured functional film can be reduced. Can be improved.

  In any one of the functional film manufacturing methods including the above-described thickening process, the thickening process may be repeated a plurality of times so that the overlapping application regions for each thickening process do not overlap. By doing so, slight variations in the film thickness in the functional film formed on the substrate can be offset by slight variations in the film thickness in the functional film formed in each thickening step. The variation in film thickness as a whole of the functional film can be further reduced.

  In any one of the functional film manufacturing methods described above, a laminated structure is formed by repeating the first application step and the second application step using an ink different from the ink for one partitioned area. A laminating step for forming the overlapping coating region in the laminating step at a position that does not overlap the overlapping coating region when the functional film is formed on the surface of the substrate. May be. By performing such a lamination process, an optimal functional film can be manufactured according to the intended use of the functional film and the required characteristics. Moreover, even if there is a region where the distribution of the film characteristics is deteriorated due to the variation in the film thickness in the overlapping application region of the functional film formed on the substrate, there is a region where the distribution of the film characteristics of the two functional films is deteriorated. As a result, the deterioration of the distribution of the film characteristics of the entire functional film to be manufactured can be reduced.

  The organic EL functional film may be formed using any one of the functional film manufacturing methods described above. Further, the organic EL functional film may be applied to an organic EL element. Further, the organic EL element may be applied to a lighting device or a display device. Thereby, an organic EL functional film, an organic EL element, an illumination device, and a display device having excellent characteristics can be provided.

  You may form an organic solar cell functional film using the manufacturing method of one of the functional films mentioned above. Moreover, you may apply the said organic solar cell functional film to an organic solar cell element. Thereby, an organic solar cell functional film having excellent characteristics and an organic solar cell element can be provided.

  The organic semiconductor functional film may be formed using any one of the functional film manufacturing methods described above. Moreover, you may apply the said organic-semiconductor functional film to an organic-semiconductor element. Thereby, the organic-semiconductor functional film and organic-semiconductor element provided with the outstanding characteristic can be provided.

  According to the method for manufacturing a functional film according to the present invention, even when the functional film is formed by scanning the coating head a plurality of times with respect to one coating region, the film thickness unevenness of the functional film is sufficiently suppressed, Occurrence of light emission unevenness in the film can be sufficiently prevented.

6 is a schematic diagram for explaining a method for producing a functional film according to Embodiment 1. FIG. It is an enlarged view of the scanning range of the coating head for explaining the method for manufacturing the functional film according to the first embodiment. It is an enlarged view of the scanning range of the coating head for explaining the method for manufacturing the functional film according to the first embodiment. It is an enlarged view of the scanning range of the coating head for explaining the method for producing a functional film according to Modification 1. It is an enlarged view of the scanning range of the coating head for explaining the method for producing a functional film according to Modification 1. 10 is an enlarged view of a coating region for explaining a method for manufacturing a functional film according to Modification 2. FIG. 10 is an enlarged view of a coating region for explaining a method for producing a functional film according to Modification 3. FIG. It is an enlarged view of the scanning range of the coating head for demonstrating the manufacturing method of the functional film which concerns on the modification 4. It is an enlarged view of the scanning range of the coating head for demonstrating the manufacturing method of the functional film which concerns on the modification 4. It is sectional drawing of each process for demonstrating the manufacturing method of the functional film which concerns on Example 2 of Embodiment. It is sectional drawing of each process for demonstrating the manufacturing method of the functional film which concerns on Example 2 of Embodiment. It is sectional drawing of each process for demonstrating the manufacturing method of the functional film which concerns on Example 2 of Embodiment. It is sectional drawing of each process for demonstrating the manufacturing method of the functional film which concerns on Example 3 of Embodiment. It is sectional drawing of each process for demonstrating the manufacturing method of the functional film which concerns on Example 3 of Embodiment. 6 is an enlarged view of a scanning range of a coating head for explaining a method for producing a functional film according to Comparative Example 1. FIG. 6 is an enlarged view of a scanning range of a coating head for explaining a method for producing a functional film according to Comparative Example 1. FIG. It is an enlarged view of the scanning range of the coating head for demonstrating the manufacturing method of the functional film which concerns on the comparative example 2. FIG. It is an enlarged view of the scanning range of the coating head for demonstrating the manufacturing method of the functional film which concerns on the comparative example 2. FIG.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a method for producing a functional film according to the present invention will be described in detail with reference to the drawings based on embodiments or modifications. In addition, this invention is not limited to the content demonstrated below, In the range which does not change the summary, it can change arbitrarily and can implement. In addition, the drawings used for the description of the embodiment or the modification schematically show the functional film produced by the method for producing the functional film according to the present invention or an intermediate thereof, and are intended to deepen understanding. Emphasis, enlargement, reduction, omission, etc. are performed, and there is a case where the scale or shape of each functional film or its intermediate is not accurately represented. Furthermore, the various numerical values used in the embodiment or the modification are only examples, and can be variously changed as necessary.

<Embodiment 1>
First, a method for manufacturing a functional film according to Embodiment 1 of the present invention will be described with reference to FIGS. 1 to 3. FIG. 1 is a schematic view for explaining a method of manufacturing a functional film according to this embodiment. 2 and 3 are enlarged views of the scanning range of the coating head for explaining the functional film manufacturing method according to the present embodiment.

  As shown in FIG. 1, an application region 12 (shown by a solid line) for applying an ink made of an organic material that is a functional film material is partitioned on a surface 11a of a substrate 11 in advance. In the present invention, one partitioned area is a continuous film in which the ink applied to form a functional film is a film formed by ink immediately after coating (hereinafter referred to as a coated film). It refers to the area that becomes the coating film. For example, when the coating film is divided and formed by a partition wall formed on the substrate, the regions on both sides of the partition wall (that is, the region located so as to sandwich the partition wall) are two different regions. Thus, it is not called a partitioned area. Further, as long as it is a region where one continuous coating film is formed, even a flat region where no bank or the like is formed around it is regarded as one partitioned region. Further, even if the partition is formed on the substrate, if the coating film completely covers the partition and the coating film is continuous on the partition, the regions on both sides of the partition are collectively partitioned. Is regarded as a single region.

  Taking an organic EL element as an example, an organic EL element generally includes a plurality of layers such as a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer between two electrodes. However, each of these layers can correspond to the functional film of the present invention. In other words, the surface of the substrate in the present invention is not limited to the direct surface of the substrate, but may be a surface on which some functional film is formed on the substrate. For example, when a light emitting layer is formed as a functional film of the present invention, ink for forming a light emitting layer is applied to a surface on which a hole transport layer or the like is formed on a substrate. When the layer is formed as the functional film of the present invention, ink for forming the hole transport layer is applied to the surface on which the hole injection layer is formed on the substrate.

  The application region 12 is surrounded by banks, partition walls, or other members (for example, a member having a surface having higher liquid repellency than the application region 12) so that the ink to be applied does not spread outside the application region 12. It is preferable. In the present embodiment example, it is assumed that a functional film constituting the organic EL lighting panel is formed, so that the coating region 12 is broadly partitioned. More specifically, the width of the coating region 12 in the direction orthogonal to the scanning direction of the coating head 13 filled with ink is wider than the width of the coating head 13, and in one scan of the coating head 13, Ink cannot be applied to the entire application region 12. For this reason, in this embodiment, the application of the ink in the application region 12 is completed by scanning the application head 13 twice.

  As specific scanning of the coating head 13, first, the coating head 13 is scanned relative to the substrate 11, and the first end 11b to the second end 11c of the coating region 12 (indicated by the arrow A in FIG. 1). Direction). Here, when the coating head 13 is scanned, ink is ejected from the coating head 13, and the ejection of the ink will be described later. The first application process is completed by ejecting ink to a part of the application region 12 while the application head 13 moves from the first end 11b to the second end 11c. In FIG. 1, the scanning range of the coating head 13 in the first coating step is shown as a first scanning range 14 (a range surrounded by a broken line).

  Next, the application head 13 that has reached the second end portion 11c of the application region 12 moves in a direction orthogonal to the ink application scanning direction (in the direction of arrow B in FIG. 1). The application head 13 is scanned relative to the substrate 11 to move the ink from the second end portion 11c of the application region 12 toward the first end portion 11b (in the direction of arrow C in FIG. 1). Discharge from the coating head 13. As described above, the application head 13 moves from the second end portion 11c to the first end portion 11b, and the remaining portion of the application region 12 (the portion of the application region 12 where the ink application has not been completed by the first application step). The second application process is completed by discharging ink. In FIG. 1, the scanning range of the coating head 13 in the second coating step is shown as a second scanning range 15 (range surrounded by a dotted line).

  Here, in the second coating process, the scanning path of the coating head 13 is parallel to the scanning path of the coating head 13 in the first coating process (that is, the arrows A and C are parallel). In addition, the second scanning range 15 of the coating head 13 in the second coating process partially overlaps the first scanning range 14 of the coating head 13 in the first coating process. In other words, the first application step and the second application step partially overlap the ink discharge ranges. Here, in FIG. 1, the overlapping scanning range is shown as an overlapping scanning range 16 (hatched range). The specific ejection of ink in the second application step will be described later in order to be described together with the ejection of ink in the first application step.

  Through the first application step and the second application step as described above, the ink is uniformly applied in the application region 12, and the formation of the functional film is completed. In this embodiment, the first application step and the second application step are performed using one application head 13, but the application heads 13 for the first application step and the second application step are separately prepared. The first coating step and the second coating step may be performed simultaneously or sequentially. That is, the first coating process and the second coating process may be performed using different coating heads. If different coating heads are used in this way, the second coating process can be started without waiting for the end of the first coating process, and the manufacturing time and manufacturing cost of the functional film can be reduced.

  In the first coating process and the second coating process, the scanning direction of the coating head 13 is opposite, but the scanning direction of the coating head 13 in the first coating process and the second coating process may be the same.

Next, ink discharge in each coating process will be described in detail with reference to FIGS. First, as shown in FIG. 2, the coating head 13 includes 216 nozzles 21 _a1 , 21 _a2 ... 21 _{a216 arranged} in parallel on a straight line at a constant pitch (in the case where an arbitrary nozzle is shown below). The distance between the adjacent nozzles 21 (nozzle pitch in the width direction of the coating head 13) is about 282 μm. In this embodiment, the opening diameter of the nozzle 21 is circular. However, the present invention is not limited to this, and various shapes can be formed in consideration of ink spreading and the like. The coating head 13 is connected to a control device (not shown), and can eject a desired amount of ink from a desired nozzle 21 at a desired timing in accordance with a control signal supplied from the control device. . In the present embodiment, the amount of ink ejected from each nozzle 21 at one time is adjusted to be the same. The number of nozzles 21 is not limited to the above number, and can be changed as appropriate according to the dimensions of the application region 12 and the like.

Next, as shown in FIG. 2, in the first coating step, when the coating head 13 scans along the arrow A from the first end portion 11b to the second end portion 11c, a desired interval (discharge pitch in the scanning direction). ) Ink is ejected from the nozzle 21. In this embodiment, ink is ejected at an ejection pitch of about 50 μm. In the first application step, the first, third, fifth, seventh, and ninth (odd-numbered) ink ejections are all performed from the (216) nozzles 21 with a desired amount of ink. However, for the second, fourth, sixth, eighth and tenth (even-numbered) ink discharges, desired ink is supplied from 214 nozzles 21 excluding the nozzles 21 _a1 and 21 _a2 . Dispense only the amount. That is, for the nozzles 21 _a1 and 21 _a2 , ink is ejected every other time (at an interval of 100 μm). Then, the ink ejected from the nozzle 21 spreads over a part of the application region 12 to form a first application region 22 (region surrounded by a broken line in FIG. 2).

  In this embodiment, for convenience of explanation, it is assumed that the number of ejections in the scanning direction is 10 and the entire application region 12 is applied, but the number of ejections is appropriately selected according to the width in the scanning direction. For example, when the width of the application region 12 in the scanning direction is about 100 mm and the ejection pitch is about 50 μm, the number of ejections in the scanning direction needs to be about 2000 times. The same applies to other embodiments and modifications described later.

Next, as shown in FIG. 3, in the second coating step, when the coating head 13 scans along the arrow C from the second end portion 11c to the first end portion 11b, a desired interval (discharge pitch in the scanning direction). ) Ink is ejected from the nozzle 21. In the second application step, ink is ejected at an ejection pitch of about 50 μm, as in the first application step. In the second application step, the first, third, fifth, seventh, and ninth (odd number of) ink ejections are all performed from the (216) nozzles 21 with a desired amount of ink. In the second, fourth, sixth, eighth, and tenth (even-numbered) ejections of ink, desired ink is ejected from 214 nozzles 21 excluding the nozzles 21 _a215 and 21 _a216 . Dispense only the amount. That is, for the nozzles 21 _a215 and 21 _a216 , ink is ejected every other time (at an interval of 100 μm). Then, the ink ejected from the nozzle 21 spreads over a part of the application region 12 to form a second application region 23 (region surrounded by a dotted line in FIG. 3).

  Further, as described above, the first scanning range 14 of the coating head 13 in the first coating process and the second scanning range 15 of the coating head 13 in the second coating process partially overlap. Corresponding to the overlapping scanning range 16 where the scanning range overlaps, an overlapping application region 24 (a region surrounded by a one-dot chain line in FIG. 3) exists in the application region 12 of the substrate 11. The number of ink discharge points per unit area of each nozzle 21 in the first application process or the second application process in the overlapping application area 24 is the first application area 22 or the second application area other than the overlapping application area 24. 23, the number of ejection points per unit area of the ink of each nozzle 21 is smaller, specifically, the number of ejection points is halved. For this reason, in the overlapping application region 24, the ejection amount is the same as the region other than the overlapping application region 24 by performing the ink discharge twice in the first application step and the second application step. In other words, the total discharge amount per unit area of the ink in the overlapping application region 24 is the first application other than the overlap application region 24 by performing two ink discharges in the first application step and the second application step. This is the same as the total ejection amount per unit area of ink in the region 22 and the second application region 23.

  As described above, the overlapping application region 24 has a certain width (in the present embodiment, two nozzles) at the boundary between the first application region 22 in the first application step and the second application region 23 in the second application step. In order to form an overlapping area using the, the total ejection amount of ink in the overlapping application area 24 is set to 564 μm, which is twice the nozzle pitch of 282 μm, and the ink in the other application areas is formed by two ink application processes. By making the total discharge amount the same, the thickness of the functional film formed in the coating region 12 can be made uniform. Thereby, in an organic EL element using a functional film having a uniform film thickness, the occurrence of uneven light emission is suppressed.

  In other words, in the present embodiment, the ink ejected in the first application step spreads while forming a gentle slope that gradually decreases from the first application region to the second application region. Thus, the ink ejected in the second application step spreads while forming a gentle slope that gradually decreases from the second application region toward the first application region. That is, in the present embodiment example, the shape approximated to the shape after the flow of the ejected ink (the shape in which the film thickness gradually decreases toward the end) at the time of ink ejection in the first application step. The thickness of the functional film in the coating region 12 can be made uniform by increasing the thickness of the functional film by ejecting ink in the second coating step.

  And an organic EL element provided with such a functional film is applied to a lighting device and a display device including an organic EL light emitting panel, thereby realizing a lighting device and a display device having excellent electrical characteristics and reliability. Can do.

  Note that the total discharge amount per unit area of ink in the overlap application region 24 completely matches the total discharge amount per unit area of ink in the first application region 22 and the second application region 23 other than the overlap application region 24. It is not necessary, and it may be adjusted within a range of −30% to + 30% of the total ejection amount per unit area of the ink in the first application region 22 and the second application region 23 other than the overlapping application region 24, and preferably Adjustment may be made within ± 10%, more preferably within ± 1%, and particularly preferably within ± 0.1%.

In this embodiment, the number of nozzles 21 in each application process that scans within the overlapping scanning range 16 (overlapping application area 24) is two (nozzles 21 _a1 , 21 _a2 , and second in the first application process). In the coating process, the nozzles 21 _a215 and 21 _a216 ) are used, but the number of nozzles 21 in each coating process that scans within the overlapping scanning range 16 may be preferably three, particularly preferably four or more. That is, it is preferable to increase the number of nozzles 21 in each coating process that scans within the overlapping scanning range 16 as much as possible, and thereby the thickness of the functional film formed in the coating region 12 can be made more uniform. .

Furthermore, in this embodiment, the ink discharge point in the first application step and the ink discharge point in the second application step are different in the overlap application region 24 (overlap scanning range 16). The discharge points may be the same. Even in such a case, the ink in the overlapping application region 24 spreads uniformly, and the film thickness of the functional film formed in the application region 12 can be made uniform.
In the range not departing from the gist of the present invention, the ink discharge point in the first application step and the ink discharge point in the second application step may be different in the nozzle pitch direction.

  In this embodiment, the application head 13 is scanned twice in order to apply ink in the application region 12, but the number of scans may be set to three or more. Even when the number of scans is set to 3 or more, the overlap scanning range 16 (overlap application region 24) is set in the first and second scans of the coating head 13, and the second and third scans are set. The overlapping scanning range 16 (overlapping application region 24) is set.

  Further, in the present embodiment example, it is assumed that the functional film used for the organic EL element is manufactured. However, the functional film used for the organic solar cell and the functional film used for the organic semiconductor are also described above. A method for producing a functional film can be applied. Thereby, an organic solar cell functional film and an organic semiconductor functional film with a uniform film thickness can be provided. And such an organic solar cell functional film is applied to an organic solar cell element, or an organic semiconductor functional film is applied to an organic semiconductor element, thereby providing an organic solar cell element and an organic material having excellent electrical characteristics and reliability. A semiconductor element can be realized.

<Modification 1>
In the first embodiment described above, after the ink is ejected twice in the first application step and the second application step, the total discharge amount per unit area of the ink in the overlapping application region 24 is other than that in the overlapping application region 24. Ink discharge from each nozzle 21 in the first application step and the second application step in the overlapping application region 24 so that the total discharge amount per unit area of ink in the first application region 22 and the second application region 23 is the same. The number of points was set to be smaller than the ink discharge point of each nozzle 21 in the first application region 22 or the second application region 23 other than the overlapping application region 24. Here, the total ejection amount per unit area of ink in the overlapping application region and the total ejection amount per unit area of ink in the first application region 22 and the second application region 23 other than the overlapping application region 24 are the same or predetermined. In order to make the difference within the range, the discharge amount of ink to the overlapping application region 24 in each application process is set to be the same as that of the first application region 22 or the second application region 23 other than the overlapping application region 24. It may be less than the discharge amount.

  In the following, referring to FIGS. 4 and 5, a method for manufacturing a functional film that adjusts the amount of ink discharged once will be described as a first modification. Here, FIGS. 4 and 5 are enlarged views of the scanning range of the coating head for explaining the method of manufacturing the functional film according to this modification. In addition, about the structure same as Embodiment 1, the code | symbol same as Embodiment 1 is attached | subjected, and the description about the content shall be abbreviate | omitted.

First, as shown in FIG. 4, in the first coating process according to the manufacturing method of Modification 1, when the coating head 13 scans along the arrow A from the first end portion 11b to the second end portion 11c, it is about 50 μm. Ink is ejected from the nozzles 21 at the ejection pitch. Further, in the first application process of the first modification, ink is ejected in a desired amount from all (216) nozzles 21 in all ink ejection times (first to tenth times in FIG. 4). To do. Here, the discharge amount of one ink of the nozzles 21 _a1 and 21 _a2 is smaller than the discharge amount of the other nozzles 21 _{a3 to} 21 _a216 , and is set to, for example, half. The setting of the discharge amount is controlled by a control device (not shown), and the discharge amount can be freely changed for each nozzle 21 in accordance with a control signal supplied from the control device.

Then, the ink ejected from the nozzle 21 spreads over a part of the application region 12 to form a first application region 22 (region surrounded by a broken line in FIG. 4). Here, the coating portion formed by the ink ejected from the nozzles 21 _a1 and 21 _a2 and the coating portion formed by the ink ejected from the nozzles 21 _{a3 to} 21 _a216 have different film thicknesses. For example, the thickness of the coating portion formed by the ink ejected from the nozzles 21 _a1 and 21 _a2 is about half of the thickness of the coating portion formed by the ink ejected from the nozzles 21 _{a3 to} 21 _a216 .

Next, as shown in FIG. 5, in the second coating step according to the manufacturing method of Modification 1, when the coating head 13 scans from the second end portion 11 c to the first end portion 11 b along the arrow C, about Ink is ejected from the nozzles 21 at an ejection pitch of 50 μm. Further, in the second coating process of the first modification, ink is ejected by a desired amount from all (216) nozzles 21 in all ink ejection times (first to tenth times in FIG. 5). To do. Here, the discharge amount of one ink of the nozzles 21 _a215 and 21 _a216 is smaller than the discharge amount of the other nozzles 21 _{a1 to} 21 _a214 , and is set to, for example, half. Then, the ink ejected from the nozzle 21 spreads over a part of the application region 12 to form a second application region 23 (region surrounded by a dotted line in FIG. 5).

  Here, the first scanning range 14 of the coating head 13 in the first coating step and the second scanning range 15 of the coating head 13 in the second coating step partially overlap as in the first embodiment. . Corresponding to the overlapping scanning range 16 where the scanning range overlaps, an overlapping application region 24 (a region surrounded by a one-dot chain line in FIG. 5) exists in the application region 12 of the substrate 11. The amount of ink discharged from each nozzle 21 in the first application step and the second application step in the overlapping application region 24 is the same as that in the first application region 22 or the second application region 23 other than the overlapping application region 24. The amount of ink discharged from the nozzle 21 is smaller than one discharge, and specifically, the amount of discharge is halved. For this reason, in the overlapping application region 24, the ejection amount is the same as the region other than the overlapping application region 24 by performing the ink discharge twice in the first application step and the second application step. In other words, the total discharge amount per unit area of the ink in the overlapping application region 24 is the first application other than the overlap application region 24 by performing two ink discharges in the first application step and the second application step. This is the same as the total ejection amount per unit area of ink in the region 22 and the second application region 23.

  As described above, also in the first modification, the overlapping application region 24 is provided with a certain width at the boundary portion between the first application region 22 in the first application step and the second application region 23 in the second application step, and the overlap. By making the total ejection amount of ink in the application region 24 the same as the total ejection amount of ink in the other application regions by two ink application processes, the film thickness of the functional film formed in the application region 12 is uniform. Can be.

<Modification 2>
In the first embodiment described above, ink is ejected in the overlapping application region 24 by alternately arranging the ink ejection points in the first application process and the ink ejection points in the second application process in the scanning direction of the application head 13. However, the position of the ink ejection point in the overlapping application region 24 may be adjusted so as to form various patterns. An example of another pattern formation of such discharge points will be described as a second modification example with reference to FIG. Here, FIG. 6 is an enlarged view of a coating region for explaining the method of manufacturing the functional film according to this modification. In addition, about the structure same as Embodiment 1, the code | symbol same as Embodiment 1 is attached | subjected, and the description about the content shall be abbreviate | omitted.

  As shown in FIG. 6, in the overlapping application region 24, a checkered pattern is formed by the first discharge points 31 in the first application process and the second discharge points 32 in the second application process. That is, the first discharge points 31 and the second discharge points 32 are alternately arranged in the scanning direction of the coating head 13 and the direction orthogonal thereto. With such an arrangement, the numbers of the first discharge points 31 and the second discharge points 32 are the same. In FIG. 6, the number of discharge points of each nozzle 21 is 10 in each application step. However, the number of discharge points is changed depending on the width of the application region 12 in the scanning direction as in the first embodiment. In some cases, a larger number of discharge points exist, and the number of the first discharge points 31 and the second discharge points 32 may be different depending on the number of discharge points.

  Thus, even when various patterns are formed according to the ink ejection points, overlapping application areas are formed at the boundary between the first application area 22 in the first application process and the second application area 23 in the second application process. 24 is provided with a constant width, and the total amount of ink discharged in the overlapping application region 24 is made equal to the total amount of ink discharged in the other application regions by two ink application processes, so that The film thickness of the formed functional film can be made uniform.

<Modification 3>
Although the checkered pattern example has been described as the second modification as the ink ejection pattern in the overlapping application region 24, a case where a more complicated pattern is formed will be described as a third modification with reference to FIG. Here, FIG. 7 is an enlarged view of a coating region for explaining the method of manufacturing a functional film according to this modification. In addition, about the structure same as Embodiment 1 and Modification 2, the code | symbol same as Embodiment 1 and Modification 2 is attached | subjected, and the description about the content shall be abbreviate | omitted.

  As can be seen from FIG. 7, in Modification 3, the number of nozzles 21 that move in the overlapping application region 24 (overlapping scanning range 16) is four in both the first application step and the second application step. That is, the width of the four nozzles 21 corresponds to the overlapping application region 24. In the overlap application region 24, the first discharge point 31 in the first application step is a boundary between the first application region 22 other than the overlap application region 24 and the overlap application region 24 (that is, the overlap application region 24 and one end). Toward the boundary between the second application region 23 other than the overlap application region 24 and the overlap application region 24 (that is, the overlap application region 24 and the other end), the number of ink ejection points gradually increases on the same scanning path. is decreasing. Similarly, in the overlap application region 24, the second discharge point 32 in the second application step is the first application other than the overlap application region 24 from the boundary between the second application region 23 other than the overlap application region 24 and the overlap application region 24. The number of ink ejection points on the same scanning path gradually decreases toward the boundary between the region 22 and the overlapping application region 24. Here, the gradual decrease is not limited to a complete monotonous decrease, and when the number of discharge points does not change in the central portion of the overlapping application region 24 as in this modification, or the number of discharge points slightly increases. This is also included.

  In this way, by adjusting the pattern of the ink discharge points in the first and second application steps in the overlapping application region 24, in the overlapping application region 24, the ink discharged in the first application step is changed to the first application region. The ink gradually spreads from the second application region toward the first application region, and gradually decreases toward the second application region. It will spread while forming a gentle slope. That is, in this modification, even in the overlapping application region 24, the shape after the flow of the ejected ink (the film thickness gradually decreases toward the end portion) at the time of ink ejection in the first application process. The shape of the functional film in the overlapping application region 24 can be increased by increasing the thickness of the functional film in the overlapping application region 24 by ejecting ink in the second application step. It can be made uniform.

  In this modification, the shape of the ink in the overlapping application region 24 (that is, the inclination of the film thickness) is controlled by adjusting the pattern of the ink ejection points in each application process in the overlapping application region 24. Adjustments other than the quantity of such discharge points may be made. For example, the shape of the ink in the overlapping application region 24 may be controlled by adjusting the amount of ink discharged once in each application process in the overlapping application region 24. The shape of the ink in the overlapping application region 24 may be controlled by combining the adjustment of the discharge amount.

<Modification 4>
In the first embodiment and the first modification described above, the total discharge amount per unit area of ink in the first application process in the overlapping application region 24 and the per unit area of ink in the second application process in the overlap application region 24 are described. The discharge point or discharge amount of ink in each process is adjusted so that the total discharge amount is the same, but the total discharge amount per unit area of ink in the second coating process is larger than that in the first coating process. May be.

  In the following, referring to FIG. 8 and FIG. 9, the total discharge amount per unit area of ink in the second application step in the overlapping application region 24 is increased from the total discharge amount per unit area of ink in the first application step. A method of manufacturing the functional film to be performed will be described as a fourth modification. Here, FIG. 8 and FIG. 9 are enlarged views of the scanning range of the coating head for explaining the method of manufacturing the functional film according to this modification. In addition, about the structure same as Embodiment 1, the code | symbol same as Embodiment 1 is attached | subjected, and the description about the content shall be abbreviate | omitted.

First, as shown in FIG. 8, in the first coating step, when the coating head 13 scans along the arrow A from the first end portion 11b to the second end portion 11c, the nozzle 21 is ejected at a discharge pitch of about 50 μm. Ink is ejected. In the first application step, the third, sixth, and ninth (multiple of 3) ink ejections are all ejected from the (216) nozzles 21 in a desired amount. However, for the first, second, fourth, fifth, seventh, eighth, and tenth times (times other than multiples of 3), 214 nozzles excluding the nozzles 21 _a1 and 21 _a2 A desired amount of ink is ejected from the nozzle 21. That is, the nozzles 21 _a1 and 21 _a2 eject ink at intervals of 150 μm. Then, the ink ejected from the nozzle 21 spreads over a part of the application region 12 to form a first application region 22 (region surrounded by a broken line in FIG. 8).

Next, as shown in FIG. 9, in the second coating step, when the coating head 13 scans along the arrow C from the second end portion 11c to the first end portion 11b, the nozzle 21 is spaced at intervals of about 50 μm. Ink is ejected. In the second application step, the first, third, fourth, sixth, seventh, ninth, and tenth ink ejections are all desired from the (216) nozzles 21. In the second, fifth, and eighth ink discharges, a desired amount of ink is discharged from 214 nozzles 21 excluding the nozzles 21 _a215 and 21 _a216 . That is, the nozzles 21 _a215 and 21 _a216 do not eject ink at a rate of once every three times. Then, the ink ejected from the nozzle 21 spreads over a part of the application region 12 to form a second application region 23 (region surrounded by a dotted line in FIG. 9).

  Further, as described above, the first scanning range 14 of the coating head 13 in the first coating process and the second scanning range 15 of the coating head 13 in the second coating process partially overlap, and the scanning range. In the overlapping application region 24 corresponding to the overlapping scanning range 16 that is an overlapping portion, the ink discharge point of each nozzle 21 in the first application step and the second application step is the first application region other than the overlapping application region 24. 22 or the second application region 23 is adjusted to be less than the ink discharge point of each nozzle 21. In the overlapping application region 24, the ejection amount is the same as the region other than the overlapping application region 24 by performing the ink discharge twice in the first application step and the second application step. In other words, the total discharge amount per unit area of the ink in the overlapping application region 24 is the first application other than the overlap application region 24 by performing two ink discharges in the first application step and the second application step. This is the same as the total ejection amount per unit area of ink in the region 22 and the second application region 23.

  Here, in the overlapping application region 24, the ink application point in the second application process is approximately twice the ink application point in the first application process. That is, in the second application step, the amount of ink discharged per unit area in the overlapping application region 24 is greater than that in the first application step. As described above, when the ink discharge amount per unit area of the overlapping application region 24 in the second application step is increased as compared with the first application step, the ink applied in the first application step is overlapped with the overlap application region. The spread to the second application region other than 24 can be suppressed, and the thickness of the functional film formed in the application region 12 can be made more uniform. Thereby, in the organic EL element using a functional film having a uniform film thickness, the occurrence of uneven light emission is further suppressed.

  In the present modification, for the overlapping application region 24, the number of ink ejection points in the second application process is set to be larger than the number of ink ejection points in the first application process. Although the discharge amount per unit area is larger than that in the first application step, adjustments other than the number of discharge points may be performed. For example, with respect to the overlapping application region 24, the unit area of the ink in the second application step can be increased by making the one-time discharge amount of the ink in the second application step larger than the one-time discharge amount of the ink in the second application step. The per unit discharge amount may be increased by the first application process. Further, the adjustment of the discharge point and the adjustment of the single discharge amount may be performed in combination, and the discharge amount per unit area of the ink in the second application step may be larger than that in the first application step.

<Embodiment 2>
In the first embodiment, the functional film is manufactured by performing the first coating process and the second coating process once, but the first coating process and the second coating process are repeated, and the functional film is formed. A thickening step for increasing the film thickness may be performed. A method for manufacturing a functional film having the thickening step will be described as a second embodiment with reference to FIGS. Here, FIG. 10 to FIG. 12 are cross-sectional views of each step for explaining the method of manufacturing the functional film according to the second embodiment.

  First, as shown in FIG. 10, the first functional film 51 is formed in the coating region 12 surrounded by the bank 41 on the substrate 11 by using the functional film manufacturing method in the first embodiment. Here, the first functional film 51 includes the first application part 51a formed only by the first application process, the second application part 51b formed only by the second application process, and the first application process and the second application process. It is comprised from the 3rd application | coating part 51c formed when the discharged ink overlaps. That is, the first application part is a part of the functional film formed in the first application area 22 other than the overlapping application area 24, and the second application part is formed in the second application area 23 other than the overlapping application area 24. The third application part is a part of the functional film formed on the overlapping application region 24 of the substrate 11.

  Next, as shown in FIG. 11, the second functional film 52 is formed on the first functional film 51 using the method for producing a functional film in the first embodiment. Here, the first functional film 51 and the second functional film 52 are composed of the same ink, and forming the second functional film 52 increases the thickness of the functional film (thickening step). become.

  In addition, as shown in FIG. 11, the second functional film 52 also includes a first application part 52a formed only by the first application process, a second application part 52b formed only by the second application process, and the first application. It is comprised from the 3rd application part 52c formed when the ink discharged in the process and the 2nd application process overlaps. Here, in the thickening step for forming the second functional film 52, the third application portion 52c of the second functional film 52 is formed at a position that does not overlap with the third application portion 51c of the first functional film 51. . In other words, in the thickening step, the overlapping coating region 24 in the thickening step is formed at a position that does not overlap with the overlapping coating region 24 when the functional film is formed on the surface of the substrate 11. . By doing so, a slight variation in the film thickness in the first functional film 51 (for example, a difference in film thickness between the first application part 51 a and the third application part 51 c) is reduced. (For example, the film thickness difference between the first application part 52a and the third application part 52c) can be offset, and the film thickness variation of the entire functional film to be manufactured can be further reduced.

  In addition, when it is difficult to form each overlapping application area | region of a functional film in the position which does not overlap completely, it is preferable to form at least the edge part of each overlapping application area | region in the position which does not overlap. In addition, when forming the second functional film in the film increasing step, a different discharge nozzle than that used when forming the first functional film may be used, or an ink discharge pattern different from that used when forming the first functional film may be used. Good.

  Further, in the thickening step for forming the second functional film 52, the film thickness of the second functional film 52 is made thinner than the film thickness of the first functional film 51. In other words, the ink discharge amount per unit area in the thickening step is adjusted to be smaller than the ink discharge amount per unit area when the functional film is formed on the surface of the substrate 11. Thereby, the variation in the film thickness in the upper layer located on the exposed surface side of the functional film (that is, the portion located on the side opposite to the substrate 11) can be further reduced, and the uppermost layer ( The flatness of the functional film on the exposed surface can be improved. Thereby, in the organic EL element etc. using the said functional film, generation | occurrence | production of light emission nonuniformity is suppressed further.

  Next, as shown in FIG. 12, the third functional film is formed on the second functional film 52 by using the functional film manufacturing method according to the first embodiment, similarly to the thickening step for forming the second functional film 52. 53 is formed. Here, the third functional film 53 is also composed of the same ink as the first functional film 51 and the second functional film 52, and forming the third functional film 53 further increases the thickness of the functional film. (Thickening process). Similarly to the first functional film 51 and the second functional film 52, the third functional film 53 is also formed by the first application part 53a formed only by the first application process and the second application process only by the second application process. It is comprised from the application part 53b and the 3rd application part 53c formed when the ink discharged in the 1st application process and the 2nd application process overlaps. Further, in the thickening process for forming the third functional film 53, the third application part 53 c of the third functional film 53 is the first functional film 51 in the same way as the thickening process for forming the second functional film 52. The third application part 51c and the second functional film 52 are formed at positions that do not overlap with the third application part 52c. As a result, slight variations in film thickness in the first functional film 51, the second functional film 52, and the third functional film can be offset each other, and the variation in film thickness as a whole of the functional film to be manufactured is further increased. Can be reduced.

  In the thickening process for forming the third functional film 53, the thickness of the third functional film 53 is set to be larger than the thickness of the second functional film 52, as in the thickening process for forming the second functional film 52. make it thin. Thereby, the variation in the film thickness in the upper layer located on the exposed surface side of the functional film can be further reduced, and the flatness of the functional film in the uppermost layer of the manufactured functional film can be improved.

  Through the above steps, the formation of the functional film 60 in a state where the first functional film 51, the second functional film 52, and the third functional film 53 are stacked (that is, in a state where the film thickness is increased) is completed. The thickening step is not limited to two times, and can be changed as appropriate according to the required characteristics of the functional film 60 and the intended use.

<Embodiment 3>
In Embodiment 2, the thickness of the functional film is increased by laminating the same ink, but a laminating step of laminating different inks may be performed. A method of manufacturing a functional film having the lamination step will be described as Embodiment 3 with reference to FIGS. Here, FIG. 13 and FIG. 14 are cross-sectional views of each step for explaining the method of manufacturing the functional film according to the third embodiment. In addition, about the structure same as Embodiment 2, the code | symbol same as Embodiment 2 is attached | subjected, and the description about the content shall be abbreviate | omitted.

  First, as shown in FIG. 13, the first functional film 51 is formed in the coating region 12 surrounded by the bank 41 on the substrate 11 by using the functional film manufacturing method in the first embodiment. As in the second embodiment, the first functional film 51 includes a first application part 51a formed only by the first application process, a second application part 51b formed only by the second application process, and a first application process. And a third application part 51c formed by overlapping the ink ejected in the second application process.

  Next, as shown in FIG. 14, the second functional film 61 is formed on the first functional film 51 by using the functional film manufacturing method in the first embodiment. Here, the first functional film 51 and the second functional film 61 are composed of different inks. In order to distinguish the formation of the second functional film 61 from ink having different characteristics from the thickening process. This is called a lamination process.

  Further, as shown in FIG. 14, the second functional film 61 also includes a first application part 61a formed only by the first application process, a second application part 61b formed only by the second application process, and the first application. It is comprised from the 3rd application | coating part 61c formed when the ink discharged in the process and the 2nd application | coating process overlaps. Here, in the stacking process for forming the second functional film 61, the third application portion 61c of the second functional film 61 is formed at a position that does not overlap with the third application portion 51c of the first functional film 51. In other words, in the lamination step, the overlapping application region 24 in the lamination step is formed at a position that does not overlap with the overlapping application region 24 when the functional film is formed on the surface of the substrate 11. By doing so, there is a region where the distribution of film characteristics is deteriorated due to a slight variation in the film thickness of the first functional film 51 (for example, the film thickness difference between the first application part 51a and the third application part 51c). Even if it does, it does not overlap with the area | region where distribution of the film | membrane characteristic by the slight variation (for example, film thickness difference of the 1st application part 61a and the 3rd application part 61c) in the 2nd functional film 61 deteriorated. Thus, the deterioration of the distribution of the film characteristics of the entire functional film to be manufactured can be reduced.

  In addition, the lamination process in the present embodiment example and the thickening process in the embodiment example 2 are combined, the respective functional films made of inks having different characteristics are laminated according to the present embodiment example 3, and the respective functional films are The thickness may be increased according to the second embodiment. In this case, it is preferable that the overlapping application regions in all the functional films do not overlap each other. Further, when it is difficult to form the overlapping application regions of the functional film at positions that do not completely overlap, it is preferable to form at least the end portions of the overlapping application regions at positions that do not overlap. Furthermore, when forming the second functional film in the stacking step, a different discharge nozzle from that used when forming the first functional film may be used, or a different ink discharge pattern may be used than when forming the first functional film.

<Example>
Next, the evaluation result of the functional film manufactured by the functional film manufacturing method according to the present invention and the conventional functional film manufacturing method will be described. For the evaluation of the functional film, Examples 1 to 6 manufactured by the method for manufacturing a functional film according to the present invention, and Comparative Examples 1 and 2 manufactured by a conventional method for manufacturing a functional film, a total of eight examples. And a comparative example. Below, the specific manufacturing method of each Example and a comparative example is demonstrated.

Example 1
A glass substrate on which ITO (about 150 nm) is formed is subjected to UV / O ₃ cleaning, and the functional film solution (2 wt%) is 40 nm in thickness by an ink jet method to function according to the manufacturing method of Embodiment 1 described above. A film was formed. More specifically, during the application, the nozzle pitch was 282 μm, and the droplet discharge pitch in the scanning direction was 50 μm. The number of nozzles used for coating was 216, and the coating head was adjusted so that two nozzles would be in the overlapping scanning range (overlapping coating region) by bidirectional coating. In the overlapping scanning range, the droplet discharge pitch in the scanning direction is 100 μm, and droplets are alternately discharged by two coatings (the first coating step and the second coating step). The number was the same in the first application step and the second application step. A single discharge amount was set to be the same in all regions, and the discharge amount per unit area was set to be equal between the overlapping application region and the other application regions. Under the above-mentioned conditions, the size of the entire application area by two scans was about 121 mm (nozzle pitch direction) × about 119 mm (discharge pitch direction). Thereafter, the functional film was vacuum-dried.

(Example 2)
The manufacturing method is basically the same as that of the first embodiment. As a difference from Example 1, in the bidirectional coating, an overlapping scanning range for 3 nozzles was provided. That is, the number of nozzles that scan the overlapping application region is one more than that in the first embodiment.

(Example 3)
The manufacturing method is basically the same as that of the first embodiment. The difference from Example 1 was that an overlapping scanning range for 5 nozzles was provided in bidirectional coating. That is, the number of nozzles that scan the overlapping application region is three more than in the first embodiment.

Example 4
The manufacturing method is basically the same as that of the first embodiment. The difference from Example 1 was that an overlapping scanning range for 10 nozzles was provided in bidirectional coating. That is, the number of nozzles that scan the overlapping application region is eight more than in the first embodiment.

(Example 5)
The manufacturing method is basically the same as that of the first embodiment. The difference from Example 1 was that an overlapping scanning range for 20 nozzles was provided in bidirectional coating. That is, the number of nozzles that scan over the overlapping application region is 18 more than in the first embodiment.

(Example 6)
The glass substrate on which ITO (about 150 nm) is formed is subjected to UV / O ₃ cleaning, and the manufacturing method of Modification 4 described above is applied so that the functional film solution (2 wt%) has a film thickness of 40 nm by the inkjet method. The functional film was formed. Specifically, the discharge amount per time is the same in all regions, the discharge pitch of the overlapping scanning range (overlapping application region) in the first application step is 150 μm, and the overlapping scanning range (overlapping application region) in the second application step. With the discharge pitch of 75 μm, the number of discharge points in the overlapping application region is varied, and the discharge amount per unit area of the overlapping application region discharged in the first application step is overlapped in the second application step. The discharge amount per unit area of the coating area was reduced. The other manufacturing process conditions were the same as those in Example 4 described above.

(Comparative Example 1)
As shown in FIGS. 15 and 16, the first application process and the second application process are performed without setting the overlapping scanning range as in the first to sixth embodiments so as not to be applied redundantly. A functional film was formed. The other manufacturing process conditions were the same as in Example 1 described above. FIGS. 15 and 16 are enlarged views of the scanning range of the coating head for explaining the method of manufacturing the functional film according to Comparative Example 1, and the same reference numerals are used for the same configurations as those in Embodiment 1 described above. Is attached.

(Comparative Example 2)
As in Comparative Example 1, the first application step and the second application step are performed without setting the overlapping scan range, and as shown in FIGS. 17 and 18, In a portion where the second scanning range in the second coating step is close, a nozzle that does not discharge ink is provided to reduce the discharge amount per unit area at the boundary portion between the first coating region and the second coating region. A functional film was formed. More specifically, no ink was ejected from the nozzle 21 _a2 in the first coating step, and no ink was _ejected from the nozzle 21 _a215 in the second coating step. The other manufacturing process conditions were the same as in Comparative Example 1 described above. 17 and 18 are enlarged views of the scanning range of the coating head for explaining the method of manufacturing the functional film according to the comparative example 2, and the same reference numerals are given to the same configurations as those of the first embodiment described above. Is attached.

  And as this evaluation method, with respect to the functional film of Examples 1-6 manufactured by the manufacturing method mentioned above and Comparative Examples 1 and 2, a fluorescent lamp or Na lamp is irradiated, and a 1st application area | region and a 2nd application | coating area | region Visual observation of the boundary part (joint area | region) was performed. A table summarizing the evaluation results is shown below. It should be noted that, at locations where the film thickness variation of the functional film is large, streaky unevenness (hereinafter referred to as “straight unevenness”) along the scanning direction of the coating head is observed by visual observation. It is in. In addition, it is easier to see stripes when the Na lamp is irradiated and observed than a fluorescent lamp.

The meanings of the symbols in Table 1 are as follows.
XX Three or more clear stripes were found.
× Two clear stripes were found.
△ One streak was clearly thinner than ×.
〇 One very thin stripe was found.
◎ No stripes were found.

  As shown in the above table, the functional films (Examples 1 to 6) formed by the manufacturing method of the present invention were observed by irradiating with a fluorescent lamp and a Na lamp, and the first coating area and the second coating area were observed. No stripe unevenness was found at the boundary with the coating region, or only fine stripe unevenness that did not affect the characteristics of the functional film was found, and the film thickness unevenness was sufficiently suppressed. Further, by increasing the number of overlapping nozzles in the overlapping scanning range, the film thickness unevenness of the formed functional film is further suppressed.

  On the other hand, when the functional films (Comparative Examples 1 and 2) formed by the conventional manufacturing method were observed by irradiating with a fluorescent lamp and a Na lamp, a plurality of stripes were observed. That is, in the functional films of Comparative Examples 1 and 2, the film thickness unevenness is not suppressed, and it is considered that the characteristics of the functional film are also affected.

  The functional film produced by the method for producing a functional film according to the present invention can be used as an organic EL functional film, an organic solar cell functional film, and an organic semiconductor functional film. Moreover, these functional films can be applied to an organic EL element, an organic solar cell element, an organic semiconductor element, a lighting device, and a display device.

11 substrate 11a surface 11b first end 11c second end 12 coating region 13 coating head 14 first scanning range 15 second scanning range 16 overlap the scanning range _{21 (21 a1, ···, 21} a216) nozzle 22 first Application area 23 Second application area 24 Overlapping application area 31 First discharge point 32 Second discharge point 41 Bank 51 First functional film 51a First application part 51b Second application part 51c Third application part 52 Second functional film 52a First 1 coating part 52b 2nd coating part 52c 3rd coating part 53 3rd functional film 53a 1st coating part 53b 2nd coating part 54c 3rd coating part 60 functional film 61 2nd functional film 61a 1st coating part 61b 2nd coating Part 61c Third application part 70 Functional film

Claims (18)

A functional film manufacturing method for forming a functional film by applying ink to one area partitioned on a surface of a substrate, wherein the coating head filled with the ink is scanned relative to the substrate. A first application step of forming a first application region by discharging the ink to a part of the partitioned one region from a plurality of nozzles of the application head;
The coating head is scanned relative to the substrate so as to be parallel to the scanning path of the coating head in the first coating step and part of the scanning range overlaps, and the partitioned one region A second application step of discharging the ink to at least a part of the remaining part to form a second application region,
The total ejection amount per unit area of the ink in the overlapping application region of the substrate corresponding to the overlapping scanning range in the first application step and the second application step is the first application region other than the overlapping application region and the The ink discharge amount in the first application step and the second application step is adjusted so that the total discharge amount per unit area of the ink in the second application region is within a range of −30% to + 30%. A method for producing a functional film.   In each of the first application step and the second application step, the number of ejection points per unit area of the ink in the overlap application region is the first application region and the second application region other than the overlap application region. The method for producing a functional film according to claim 1, wherein the number is less than the number of ejection points per unit area of the ink. In each of the first application step and the second application step, the discharge amount of the ink in the overlap application region is the amount of the ink in the first application region and the second application region other than the overlap application region. The method for producing a functional film according to claim 1, wherein the functional film is less than a single ejection amount of ink. The plurality of nozzles are juxtaposed at a constant pitch on a straight line in the coating head,
4. The method of manufacturing a functional film according to claim 1, wherein, in the second application step, three or more nozzles scan within the overlapping scanning range. 5.   5. The method of manufacturing a functional film according to claim 1, wherein, in the second application step, the discharge amount per unit area of the ink in the overlapping application region is increased more than in the first application step. .   In the second application step, at least one of the number of ejection points of the ink in the overlapping application region and the single ejection amount of the ink from one nozzle is larger than that in the first application step. The method for producing a functional film according to claim 5.   In each of the first coating step and the second coating step, the first coating region other than the overlapping coating region or the boundary between the second coating region and the overlapping coating region is set to the end of the overlapping coating region. The quantity of at least one of the number of ejection points of the ink and the ejection quantity of the ink from one nozzle on the same scanning path is gradually reduced. The manufacturing method of the functional film as described in a term.   8. The method for producing a functional film according to claim 1, wherein, in the second application step, a discharge point of the ink in the overlapping application region is different from a discharge point in the first application step. 9.   The method for manufacturing a functional film according to claim 1, wherein, in the second application step, the ink discharge point in the overlapping application region is the same as the discharge point in the first application step.   The method for manufacturing a functional film according to claim 1, wherein different application heads are used in the first application process and the second application process.   An organic EL functional film formed using the method for producing a functional film according to claim 1.   An organic EL device comprising the organic EL functional film according to claim 11.   The illuminating device using the organic EL element of Claim 12.   A display device using the organic EL element according to claim 12.   An organic solar cell functional film formed using the method for producing a functional film according to any one of claims 1 to 10.   An organic solar cell element comprising the organic solar cell functional film according to claim 15.   An organic semiconductor functional film formed by using the method for producing a functional film according to claim 1.   An organic semiconductor element comprising the organic semiconductor functional film according to claim 17.

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