JP2009078500A - Letterpress printing apparatus and polymer EL element manufacturing method using the apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a letterpress printer capable of easily forming micropatterns of uniform thicknesses without any uneven printing especially in an electronic component for displaying, and a method for manufacturing a high-polymer EL element by using the same. <P>SOLUTION: The letterpress printer is provided with a press body equipped with a press to rotate, a substrate surface plate for mounting a printed substrate, and an ink supplying means for supplying ink onto the press. This printer is further provided with two doctors arranged in parallel in the rotational direction of an ink roll to scratch off surplus ink from the surface of the ink roll for supplying ink to the press. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a letterpress printing apparatus for forming a fine print pattern by transferring ink placed on the convex part of a resin letterpress onto a substrate, and a method for producing a polymer EL element using the apparatus.

  In recent years, attempts have been made to use a known printing method in forming a fine pattern of an electronic component. Particularly in the display field, in order to cope with an increase in screen size and cost, studies are being made on pattern formation of electronic components by a printing method.

  The printing method is excellent in mass productivity and can reduce the manufacturing cost. Specific methods include offset printing and gravure printing.

  Flexographic printing is a printing method using a flexible letterpress made of rubber or resin, an ink roll engraved with fine depressions (cells) on the surface called an anilox roll, and solvent-dried ink. Widely used for simple printed materials such as paper. This flexographic printing is particularly suitable for forming a thin and stable printing layer having a film thickness of about 0.01 to 0.2 μm. In addition, flexographic printing has flexibility in the relief printing plate part, and it is printing at a very low printing pressure called kiss touch, so a transparent electrode whose characteristics can be destroyed by applying a glass substrate or high pressure, etc. This is a printing method that is particularly suitable for pattern formation of electronic parts such as displays.

  Ink supply to the relief printing relief plate is performed by rotating the cylindrical plate cylinder equipped with the relief printing plate and the ink roll at approximately the same peripheral speed while applying the ink held in the cells on the surface of the ink roll to the relief of the relief printing plate. This is done by contact and transfer.

  A part of the ink roll is immersed in the ink reservoir in the ink fountain, and the ink adheres to the surface of the ink roll. A doctor in contact with the surface of the anilox roll to which ink is attached determines the ink supply amount by scraping off the extra ink adhering to the outside of the cell while filling the cell with the rotation of the ink roll. Yes.

  The cells engraved on the ink roll have shapes such as diamond type and honeycomb type. However, when printing fine patterns such as stripe patterns found in electronic components for displays, ink supply to letterpress When the amount varies, there is a problem that printing unevenness occurs, and particularly in an electronic component related to a display unit such as a color filter, the printing unevenness is directly connected to display unevenness of the display, which is a serious problem.

  If the doctor has chipping, undulation or inclination, it may cause streaky unevenness in the direction of rotation of the ink roll, which can be caused by doctor polishing / replacement or suppression of undulation by the holder. This prevents the occurrence of unevenness.

  However, even if the amount of ink adhering to the surface of the ink roll due to the ink reservoir is uneven or uneven, after the excess ink is scraped off by the doctor, streaks appear in the direction of rotation of the ink roll (vertical unevenness). There is a problem to do.

  The present invention has been made in order to solve the above-mentioned problems, and the object of the present invention is to easily form a fine pattern with a uniform film thickness that does not cause uneven printing, particularly on an electronic member for a display. An object of the present invention is to provide a relief printing apparatus and a method for producing a polymer EL element using the apparatus.

The invention described in claim 1 is a relief printing apparatus comprising a plate cylinder that rotates with a plate, a substrate surface plate on which a substrate to be printed is placed, and an ink supply means that supplies ink onto the plate.
The letterpress printing apparatus is characterized in that two doctors for removing excess ink on the surface of an ink roll for supplying ink to the plate are provided in parallel with respect to the rotation direction of the ink roll.

  The invention according to claim 2 is characterized in that, of the two doctors, 0.1 is provided between the doctor and the surface of the ink roll, which is disposed upstream of the uppermost part of the ink roll with respect to the rotation direction of the ink roll. The relief printing apparatus according to claim 1, wherein the relief printing apparatus has a gap of ˜1.0 mm.

  According to a third aspect of the present invention, of the two doctors, a blade-like doctor installed on the upstream side of the uppermost part of the ink roll with respect to the rotation direction of the ink roll is 2. The letterpress printing apparatus according to claim 1, wherein the blade tip is in contact with an inclination of 30 [deg.] Or less so as to face the rotation direction of the ink roll.

  According to a fourth aspect of the present invention, one of the two doctors is installed upstream of the top of the ink roll with respect to the rotation direction of the ink roll, and the other is relative to the rotation direction of the ink roll. The relief printing apparatus according to any one of claims 1 to 3, wherein the relief printing apparatus is installed downstream of the uppermost part of the ink roll.

  Invention of Claim 5 forms the light emitting layer of a polymer EL element using the relief printing apparatus of any one of Claims 1-4, The manufacturing method of a polymer EL element characterized by the above-mentioned It is.

  According to the present invention, it is possible to easily form a fine pattern with a uniform film thickness without printing unevenness, and electronic components such as high-quality polymer EL elements for display can be produced at low cost.

  Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic side sectional view showing an example of an embodiment of a main part of an ink roll of a relief printing apparatus according to the present invention. FIG. 2 is a schematic side sectional view showing another example of the ink roll main part of the relief printing apparatus of the present invention.

  The present invention relates to a relief printing apparatus comprising a rotary plate cylinder on which a relief plate is installed, a substrate surface plate on which a substrate is placed, and an ink supply means for applying ink to the relief plate, and is particularly applicable to a flexographic printing apparatus. Is done.

  As shown in FIG. 1, the relief printing apparatus according to the present invention includes an ink roll 11 for applying ink in contact with the surface of a flexographic plate installed on a plate cylinder, and a lower portion of the ink roll 11 is immersed in an ink reservoir 3a. It has an ink supply device composed of an ink fountain 12 and a doctor 13a for scraping off excess ink 4 adhering to the surface of the ink roll 11.

  The ink roll 11 is engraved with fine recesses (cells) for holding ink after ceramic coating or chrome coating on the surface, and the doctor 13a in contact with the surface of the ink roll is an ink roll. The ink is pushed into the cell and excess ink outside the cell is scraped off from the surface of the ink roll.

  In the letterpress printing apparatus according to the present invention, the second doctor 13b is disposed upstream of the uppermost part of the ink roll with respect to the rotation direction of the ink roll 11 relative to the doctor 13a, and the excess adhered to the surface of the ink roll 11 is disposed. The ink is scraped off. However, the second doctor 13b is installed with a slight gap without contacting the surface of the ink roll, and after the excess ink is scraped off by the second doctor, the second doctor 13b remains on the surface of the ink roll outside the cell. Ink with a uniform film thickness is left behind. If the gap between the second doctor and the surface of the ink roll is too wide, the ink film on the surface of the ink roll cannot be made uniform, and if it is too narrow, the ink roll surface may not be covered with the ink film. Therefore, about 0.1 to 1.0 mm is appropriate.

  When a blade-like doctor (doctor blade) is used as the second doctor, the angle between the surfaces of the second doctor 13b and the ink roll 11 is 30 in the direction in which the blade edge of the blade faces the rotation direction of the ink roll. A method is also conceivable in which the second doctor is laid and abutted so as to be less than or equal to 0 °, and the ink doctor surface can be uniformly left on the surface of the ink roll by the bending of the second doctor 13b.

  The installation position of the second doctor 13b is upstream of the uppermost part of the ink roll with respect to the rotation direction of the ink roll with respect to the first doctor 13a. It is desirable that the scraped ink falls directly to the ink reservoir below the ink roll along the surface of the ink roll by its own weight, so that it is desirable to be upstream of the top of the ink roll with respect to the rotation direction of the ink roll. . In particular, as shown in FIG. 2, if the second doctor 13b is installed near the liquid level of the ink reservoir, the opening of the ink fountain is blocked by the second doctor 13b, so that the solvent content from the ink reservoir is reduced. The effect of suppressing volatilization is also obtained.

  On the other hand, when the ink scraped off by the first doctor 13a falls along the surface of the ink roll, the extra ink is placed on the ink film that is made uniform by the second doctor 13b. Ink may accumulate on the doctor 13b and unevenness in scraping may occur. Therefore, the first doctor 13a is installed on the downstream side with respect to the rotation direction of the ink roll from the uppermost part of the ink roll, and the scraped ink is transferred from both ends of the first doctor 13a to the end face of the roll. It is desirable to let it fall into the pool.

  In addition, as a form of the doctor of this invention, a doctor blade and a doctor roll can be considered, and if it has a function which scrapes off the excess ink on an ink roll, another form may be sufficient.

  Hereinafter, the present invention will be described with reference to specific examples.

  Using the relief printing apparatus of the present invention, the display pixel portion for a color display panel was printed.

  The gap between the ink roll and the second doctor was set to 0.5 mm so that an ink film with a uniform thickness of 0.5 mm remained on the surface of the ink roll. The installation position is 45 ° from the top of the ink roll in the direction opposite to the rotation of the ink roll.

  On the other hand, the first doctor was placed in contact with the ink roll surface. The installation position is 10 ° in the rotation direction of the ink roll from the top of the ink roll.

  When the ink roll is rotated, the ink adheres to the surface of the ink roll from the ink pool where the lower part of the ink roll is immersed, and is lifted along the rotation, but if the ink amount in the ink pool is uneven, the surface of the ink roll The amount of ink adhering to the ink also varies.

  First, excess ink is scraped off from the ink adhered to the ink surface by the second doctor, and a uniform film having a thickness of 0.5 mm is formed on the surface of the ink roll. At this time, since the ink is leveled by the second doctor, the scraped ink is supplied even to the portion where the ink amount is insufficient, and the film thickness of the ink becomes uniform. Furthermore, the ink is sufficiently filled in the cells on the surface of the ink roll by the second doctor. Further, the excess ink scraped off by the second doctor falls in the ink reservoir in the direction opposite to the rotation direction along the surface of the ink roll due to its own weight.

  Next, the ink film uniformly formed on the surface of the ink roll is scraped off by the first doctor leaving only the ink inside the cell. Excess ink scraped off by the first doctor accumulates on the back of the first doctor, and then falls into the ink reservoir along both end faces of the ink roll.

  When the ink filled in the cells on the surface of the ink roll was transferred onto a relief plate installed on the plate cylinder and further printed on a glass substrate, a fine pattern with no unevenness or chipping could be printed. In addition, the ink scraped off by the doctor could be collected in the ink reservoir so as not to affect the printing quality, so that repeated printing could be performed with stable quality.

FIG. 2 is a schematic side sectional view showing an example of an embodiment of an ink roll main part of the relief printing apparatus of the present invention. It is the side cross-sectional schematic which shows the other example of the embodiment about the ink roll principal part of the relief printing apparatus of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Ink roll 12 ... Ink fountain 13a ... Doctor 13b ... Doctor 2 ... Plate cylinder 21 ... Letterpress 3 ... Ink 3a ... Ink reservoir 4 ... Excess ink

Claims (5)

In a relief printing apparatus having a printing cylinder equipped with a plate, a substrate platen on which a substrate to be printed is placed, and an ink supply means for supplying ink onto the plate,
2. A letterpress printing apparatus comprising two doctors arranged in parallel with respect to the direction of rotation of an ink roll for scraping off excess ink on the surface of an ink roll for supplying ink to the plate.   Of the two doctors, a gap of 0.1 to 1.0 mm is provided between a doctor installed on the upstream side of the uppermost part of the ink roll with respect to the rotation direction of the ink roll and the surface of the ink roll. The letterpress printing apparatus according to claim 1.   Of the two doctors, the blade-shaped doctor installed upstream of the top of the ink roll with respect to the rotation direction of the ink roll is the blade edge of the blade with respect to the ink roll surface. The relief printing apparatus according to claim 1, wherein the relief printing apparatus is in contact with being inclined at an angle of 30 ° or less so as to face the surface.   Of the two doctors, one is installed upstream of the top of the ink roll with respect to the direction of rotation of the ink roll, and the other is the top of the ink roll with respect to the direction of rotation of the ink roll. The letterpress printing apparatus according to any one of claims 1 to 3, wherein the letterpress printing apparatus is installed on the downstream side.   A light emitting layer of a polymer EL element is formed using the relief printing apparatus according to any one of claims 1 to 4, and a method for producing a polymer EL element.

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