JP2008134513A - Resin letterpress and manufacturing method of element panel for organic EL display - Google Patents

Abstract

The present invention provides a resin relief plate for high-definition printing that secures a certain relief depth and maintains the sharpness of the edges of relief projections without causing a reduction in relief strength, or the resin relief plate. The manufacturing method of the element panel for organic electroluminescent displays which can form the high-definition pattern of the light emitting layer of an organic electroluminescent element uniformly uniformly stably can be provided.
A resin relief plate having a relief formed by exposing and developing a photosensitive resin layer (30) laminated on a substrate (1), wherein the photosensitive resin layer (30) is light-sensitive. Resin comprising two layers (31, 32) having different scattering properties, wherein the layer (32) closer to the substrate is a layer having higher light scattering properties than the layer (31) closer to the surface layer Letterpress.
[Selection] Figure 2

Description

  The present invention relates to a resin relief plate and a method for producing an element panel for an organic EL display by patterning a light emitting layer of an organic EL (Electro Luminescence) element with high definition using the resin letterpress.

  In an organic EL element, a light emitting layer made of an organic light emitting material is formed between two opposing electrodes, and light is emitted by passing a current through the light emitting layer. Is important, and a thin film of about 100 nm is required. Further, in order to make this a display, it is necessary to pattern it with high definition.

  The organic light emitting material for forming the light emitting layer includes a low molecular material and a high molecular material. Generally, a low molecular material is formed into a thin film by a resistance heating vapor deposition method or the like, and is patterned using a fine pattern mask at this time. This method has a problem that the larger the substrate is, the more difficult patterning accuracy is.

  Therefore, recently, a method of using a polymer material as an organic light emitting material, dispersing or dissolving the organic light emitting material in a solvent to form a coating solution, and forming a thin film by a wet coating method has been tried. As the wet coating method for forming a thin film, there are a spin coating method, a bar coating method, a protruding coating method, a dip coating method, and the like. However, it is considered difficult to form a thin film by a printing method that is good at coating and patterning.

  Further, among various printing methods, in organic EL elements and displays using glass as a substrate, a method using a hard plate such as a metal printing plate such as a gravure printing method is unsuitable, and an elastic rubber blanket. An offset printing method using, and a relief printing method using an elastic rubber plate or resin plate are also suitable. Actually, as an attempt by these printing methods, a method by offset printing (for example, see Patent Document 1), a method by letterpress printing (for example, see Patent Document 2), and the like have been proposed.

  On the other hand, the polymer organic light-emitting material has poor solubility in water and alcohol solvents, and in order to form a coating liquid (hereinafter referred to as ink), it is necessary to dissolve and disperse using an organic solvent. Toluene, xylene and other aromatic organic solvents are preferred. Therefore, the ink of the organic light emitting material (hereinafter referred to as organic EL ink) is an ink of an aromatic organic solvent.

  However, a rubber blanket used for offset printing has a problem that it is easily swollen or deformed by an organic solvent such as toluene or xylene. The types of rubber used in blankets vary from olefin rubber to silicone rubber, but none of these rubbers are resistant to toluene, xylene or other solvents and are prone to swelling and deformation. It is inappropriate for EL ink printing.

  In addition, a relief printing method using an elastic relief plate includes a flexographic printing method using a rubber plate and a resin relief printing method using a resinous plate. Among these, a water development type photosensitive resin relief plate is used. If it is a system, the tolerance with respect to toluene, xylene, and other organic solvents is also high, and it can be used for printing of organic EL ink.

  For the reasons described above, as a method for printing organic EL ink containing an aromatic solvent such as toluene and xylene on a hard base material such as a glass substrate, a relief printing using a water-development type photosensitive resin relief printing is used. The printing method is optimal.

  The water-developable photosensitive resin relief plate is prepared from a plate material in which a photocurable photosensitive resin layer is laminated on a base material, and the photocurable photosensitive resin layer of this plate material is By exposing using the photomask patterned by the light-shielding part and the light transmissive part, after hardening an exposed part, it develops with water and removes an unhardened part, and formed the relief. In general, an exposure machine used for exposure of a photosensitive resin relief printing plate uses diffused light, and the light entering the resin layer of the plate material through the light transmitting portion of the photomask is itself diffused light. Due to the light scattering property of the resin layer itself, the resin layer itself diffuses and proceeds, so that the cured portion tends to spread from the exposed side toward the non-exposed side. Therefore, as shown in FIG. 1, the completed relief convex part 10 becomes a forward taper shape, but there exists an advantage that the intensity | strength of a relief improves by this.

  However, the higher the printing is, the narrower the interval between the relief recesses, so that when the projections are forward tapered, the depth of the relief becomes shallow. If the relief pitch is narrowed and the relief depth is shallow, a large amount of ink tends to enter the relief recess when supplying ink to the relief plate, and the ink that has entered the recess will be removed from the recess during ink transfer from the plate to the substrate. In some cases, the printed image may flow out, resulting in a problem that the printed image is disturbed. Therefore, in the relief formation of the resin relief printing, it is necessary to ensure a relief depth of a certain level or more.

On the other hand, by using a plate material made of a photosensitive resin having a low light scattering property, a relief resin depth can be secured, and a photosensitive resin relief plate with sharpened relief protrusions can be obtained. It is necessary to use a device that uses parallel light. That is, by exposing a photosensitive resin plate material having a low light scattering property to a plate by exposing it with a parallel light exposure apparatus, the relief convex portion is not tapered, and the inclination angle of the side surface of the relief convex portion with respect to the substrate is 90 degrees. It is possible to form a close resin relief. However, in the resin relief printing plate having a non-tapered relief, the strength of the relief is weak, causing problems such as uneven development in the relief during development, deformation of the relief during printing, and poor printing durability.
JP 2001-93668 A JP 2001-155858 A

  As described above, the photosensitive resin relief plate obtained by exposing a photosensitive resin plate material having light scattering properties with diffused light and then developing the relief resin relief plate has a relief taper shape with a forward taper shape, so that the relief is enhanced when the definition is increased. There is a problem that the depth becomes shallow. On the other hand, the photosensitive resin relief printing plate obtained by exposing and developing a photosensitive resin plate material with reduced light scattering property using parallel light has a non-tapered relief, and the relief depth can be ensured even if the definition is increased. However, the problem that the intensity | strength of a relief falls arises.

  Therefore, the present invention provides a resin relief printing plate for high-definition printing that ensures a certain relief depth and maintains the sharpness of the edges of the relief projections, while not reducing the relief strength, or this It is an object of the present invention to provide a method for producing an element panel for an organic EL display capable of uniformly and stably forming a high-definition pattern of a light emitting layer of an organic EL element using a resin relief plate.

  In order to solve the above-mentioned problem, as shown in FIG. 2, the relief protrusion 20 has a two-step taper shape in which a portion 22 near the bottom has a forward taper shape and a portion 21 near the top has a non-taper shape. It is thought that the formed photosensitive resin relief plate may be used, and the present invention has been made to obtain such a shape.

  That is, the invention according to claim 1 is a resin relief plate in which a relief is formed by exposing and developing a photosensitive resin layer laminated on a substrate, and the photosensitive resin layer has different light scattering properties. A resin relief printing plate comprising two layers, wherein the layer closer to the substrate is a layer having higher light scattering properties than the layer closer to the surface layer.

  The invention according to claim 2 is characterized in that the light-scattering layer of the photosensitive resin layer has a light scattering rate of 10% to 30% in the case of light having a wavelength of 360 nm. The resin relief printing plate according to claim 1.

  The invention according to claim 3 is characterized in that the light-scattering layer of the photosensitive resin layer has a light scattering rate of 5% or less in the case of light having a wavelength of 360 nm. The resin letterpress described in 1 or 2.

  Further, in the invention according to claim 4, a portion near the top of the relief convex portion is formed by a layer having a lower light scattering property of the photosensitive resin layer, and a portion near the bottom of the relief convex portion is the photosensitive resin layer. Of the light-scattering layer, the inclination angle of the portion near the top of the relief convex portion with respect to the substrate surface is between 85 degrees and 90 degrees, and the portion near the bottom of the relief convex portion The resin relief printing plate according to any one of claims 1 to 3, wherein an inclination angle with respect to the substrate surface is between 50 degrees and 80 degrees.

  Further, the invention according to claim 5 is an organic EL characterized in that the light emitting layer of the organic EL element is patterned by a relief printing method using the resin relief plate according to any one of claims 1 to 4. It is a manufacturing method of the element panel for a display.

  In the present invention, in the resin plate material in which the photosensitive resin layer is provided on the base material, the photosensitive resin layer is composed of two types of resin layers having different light scattering properties, and the light of the layer closer to the base material is formed. By increasing the scattering property, when this resin plate material was subjected to pattern exposure and development using a photomask with a parallel light exposure machine, the portion close to the top of the relief projection was non-tapered, and the relief projection The portion near the bottom of the portion could form a resin relief plate having a forward taper shape.

  When printing a panel with a definition of 200 pixels per inch, which is a high-definition category in an element panel for organic EL displays, a relief-shaped relief plate with a pitch of 120 μm and a line width of 20 μm is required. However, a relief depth of 100 μm or more could be secured.

  In addition, even if organic EL ink is printed using this plate, the plate will not be deformed and print lines will not be found or the plate will not be applied, and a clear print pattern corresponding to the relief pattern can be obtained. I was able to.

  Therefore, the invention according to claims 1 to 4 is a resin relief printing plate for high-definition printing that ensures a certain relief depth and maintains the sharpness of the edges of the relief projections, while not reducing the relief strength. There is an effect that it can be provided.

  The invention according to claim 5 is an organic EL display capable of uniformly and stably forming a high-definition pattern of a light emitting layer of an organic EL element, using the resin relief plate provided by any of the inventions according to claims 1 to 4. There is an effect that it is possible to provide a method for manufacturing an element panel.

  First, an embodiment of the resin relief plate of the present invention will be described.

  As described above, the resin relief printing used for patterning the light emitting layer of the organic EL element with high definition has high resistance to the organic solvent that is a solvent of the organic EL ink, particularly an aromatic organic solvent, that is, a water developing type. However, the water-developing type photosensitive resin constituting the resin relief printing plate is composed of, for example, a monomer containing a hydrophilic polymer and an unsaturated bond, a so-called crosslinkable monomer and a photopolymerization initiator. Type. In this type, polyamide, polyvinyl alcohol, cellulose derivatives and the like are used as hydrophilic polymers. Examples of the crosslinkable monomer include methacrylates having a vinyl bond, and examples of the photopolymerization initiator include aromatic carbonyl compounds. Of these, a polyamide-based water-developable photosensitive resin is preferable from the viewpoint of printing suitability.

  In addition, the polyamide-based water-developable photosensitive resin has a low light scattering property, and is controlled to increase its light scattering property by adding spherical organic fine particles of an acrylate ester having a particle size of about 2 μm. be able to.

  Therefore, by changing the concentration of the acrylic ester-based spherical organic particles in two stages and laminating a polyamide-based water-developable photosensitive resin, a light scattering property as shown in FIG. A resin plate material in which a photosensitive resin layer 30 composed of two different layers (31, 32) is laminated on the substrate 1 can be obtained. At this time, be sure to add spherical fine particles having a volume concentration of several percent to 10% to the layer 32 on the side close to the base material so that the light scattering property of the layer 32 on the side close to the base material becomes high, On the other hand, the spherical organic fine particles are not added to the layer 31 on the side close to the surface layer or only a small amount of the spherical organic fine particles are added, and the light scattering property of the layer 31 on the side close to the surface layer is kept low.

  As a result, in the case of light having a wavelength of 360 nm, the light scattering rate of the layer 32 closer to the substrate is 10% or more and 30% or less, while the light scattering rate of the layer 31 closer to the surface layer is 5%. Fits below.

  The resin relief printing plate of the present invention is produced by pattern exposure of the photosensitive resin layer of the resin plate material using a negative photomask with a parallel light exposure machine, and then brush development with hot water at 30 ° C. to form the unexposed resin. After washing out and drying in an oven at 70 ° C., post-exposure was performed to form a relief having a predetermined pattern.

  In the photosensitive resin layer composed of two layers of the resin plate material, the layer on the side close to the substrate is not added with the acrylate-based spherical organic fine particles or a very small amount is added to the layer close to the surface layer. Since acrylate-based spherical fine particles having a volume concentration of several percent to about 10% are added, the resin relief printing plate of the present invention is a portion close to the top of the relief projection 20 as shown in FIG. 21, the inclination angle is basically 85 to 90 degrees with respect to the bottom surface of the substrate, and on the other hand, the inclination angle of the portion 20 near the bottom of the relief projection 20 is controlled to about 50 to 80 degrees. It is possible.

  Next, since the element panel for organic EL displays was created by performing light emitting layer printing using the resin relief printing plate of this invention, the one Embodiment is described.

The organic EL element which comprises the element panel for organic EL displays is formed on a glass substrate. A pixel electrode patterned as an anode is provided on a glass substrate. The material of the pixel electrode is ITO (indium tin composite oxide), IZO (indium zinc composite oxide), tin oxide, zinc oxide, indium oxide. Transparent electrode materials such as zinc aluminum composite oxide can be used. ITO is preferred because of its low resistance, solvent resistance, and high transparency. ITO is formed on a glass substrate by a sputtering method and patterned by a photolithographic method to form a line-shaped pixel electrode.

  After the line-shaped pixel electrode is formed, an insulating layer is formed by photolithography using a photosensitive material between adjacent pixel electrodes. The insulating layer was formed by first coating the entire surface with an insulating photoresist material by a slit coating method and then patterning the insulating layer in a line shape in the space portion of the pixel electrode using the photolithography method.

  After forming the insulating layer, a hole transport layer is formed. Examples of the hole transport material for forming the hole transport layer include polyaniline derivatives, polythiophene derivatives, polyvinylcarbazole (PVK) derivatives, poly (3,4-ethylenedioxythiophene) (PEDOT), and the like. These materials are dissolved or dispersed in a solvent to form a hole transport material ink, and are applied onto the entire surface of the substrate on which the pixel electrode and the insulating layer are formed by using a spin coat method or a die coat method to form a hole transport layer. It is also possible to form a pattern in accordance with the pixel electrode pattern using a relief printing method.

  After forming the hole transport layer, an organic light emitting layer is formed. Organic light-emitting materials forming the organic light-emitting layer are, for example, coumarin-based, perylene-based, pyran-based, anthrone-based, porphyrene-based, quinacridin-based, N, N′-dialkyl-substituted quinacdolin-based, naphthalimide-based, N, N′-diaryl. Dispersed luminescent dyes such as substituted pyrrolopyrrole and iridium complexes in polymers such as polystyrene, polymethylmethacrylate, and polyvinylcarbazole, and polyarylene, polyarylene vinylene, and polyolefin polymer materials Is mentioned.

  These organic light emitting materials are dissolved or dispersed in a solvent to form an organic EL ink. Examples of the solvent for dissolving or dispersing the organic light emitting material include toluene, xylene, acetone, anisole, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, or a mixed solvent thereof. Among them, aromatic organic solvents such as toluene, xylene, and anisole are preferable from the viewpoint of the solubility of the organic light emitting material.

  The organic light emitting layer is formed by a relief printing method using the resin relief plate of the present invention. The printing machine used for forming the organic light emitting layer can be any letterpress printing machine that prints on a flat plate, but a printing machine as shown below is desirable.

  This printing machine has an ink tank, an ink chamber, an anilox roll, and a plate cylinder to which the resin relief plate of the present invention is attached. The ink tank contains organic EL ink diluted with a solvent, and the organic EL ink is fed into the ink chamber from the ink tank. The anilox roll rotates in contact with the ink supply part of the ink chamber and the plate cylinder.

  With the rotation of the anilox roll, the organic EL ink supplied from the ink chamber is uniformly held on the anilox roll surface, and then the film thickness is uniform on the relief convex portion of the resin relief plate of the present invention attached to the plate cylinder. Metastasize. Further, the substrate to be printed is fixed on a slidable substrate fixing base, and is moved to the printing start position while adjusting the position by the position adjustment mechanism of the resin relief printing pattern and the substrate pattern of the present invention. The relief convex portion of the resin relief printing plate of the present invention further moves while contacting the substrate in accordance with the rotation, and the organic EL ink is transferred by patterning to a predetermined position on the substrate.

  After the organic light emitting layer is formed, the cathode layer is formed in a line pattern orthogonal to the pixel electrode line pattern. As the material for the cathode layer, materials according to the light emitting characteristics of the organic light emitting layer can be used. For example, simple metals such as lithium, magnesium, calcium, ytterbium and aluminum and alloys of these with stable metals such as gold and silver Etc. Alternatively, a conductive oxide such as indium, zinc, or tin can be used. As a formation method of a cathode layer, the formation method by the vacuum evaporation method using a mask is mentioned.

  Finally, in order to protect these organic EL element structural bodies from external oxygen and moisture, the element panel for organic EL display can be obtained by sealing and sealing with a glass cap and an adhesive.

  Examples of the present invention will be specifically described below.

  In this embodiment, the relief pattern is a line pattern having a pitch of 120 μm and a line width of 20 μm, and the inclination angle of the portion where the relief convex portion is close to the top is in the range of 85 degrees to 90 degrees with respect to the substrate surface. The inclination angle of the portion close to the bottom is an example of producing a resin relief plate in the range of 50 to 80 degrees with respect to the substrate surface, and the light emission layer is formed using the relief plate, and the definition is 1 An example of producing an element panel for a passive matrix type organic EL display having 200 pixels per inch (hereinafter referred to as 200 PPI) will be described.

<Example 1>
The resin relief printing plate of Example 1 has a two-step tapered shape in which the inclination angle of the portion close to the top is 90 degrees with respect to the substrate surface and the inclination angle of the portion close to the bottom is 50 degrees with respect to the substrate surface. A relief having a convex portion is formed. The resin relief printing plate of Example 1 was prepared as follows.

  First, as a resin plate material, a photosensitive resin layer having a total thickness of 150 μm is formed on a steel substrate having a thickness of 200 μm, and this photosensitive resin layer has an acrylic ester-based side 100 μm on the side close to the substrate. The spherical organic fine particles were used in a layer containing 10% by volume, and the side close to the surface layer of 50 μm was a layer containing no acrylate-based spherical organic fine particles.

  Next, a negative pattern photomask corresponding to the printed pattern of the light emitting layer is arranged with a gap of 25 μm with respect to the exposed surface of the photosensitive resin layer of the resin plate material, and parallel with an exposure energy of 40 mJ. The resin relief printing plate of Example 1 was formed by exposing to light and then washing out the uncured resin with warm water at 30 ° C. using a brush developing machine. The relief depth of the resin relief printing plate of Example 1 was 100 μm or more.

  Subsequently, the element panel for organic EL displays of Example 1 was produced as follows by the method of printing and forming a light emitting layer using the resin relief printing plate of Example 1.

  First, an ITO (indium-tin oxide) thin film is formed on a 200 mm square glass substrate by sputtering, and the ITO film is patterned by photolithography and etching with an acid solution. Pixel electrodes were formed so that four displays could be taken. The line pattern of the pixel electrodes constituting the display was a pattern formed with a line width of 20 μm and a space of 20 μm.

  Next, an insulating layer was formed using a photoresist material between the pixel electrodes so as to cover the end portions of the pixel electrode lines.

  Next, a polymer film made of PEDOT was formed on the insulating layer as a hole transport layer by a spin coating method.

  Furthermore, using organic EL ink in which polyphenylene vinylene derivative, an organic light emitting material, is dissolved in toluene to a concentration of 1%, the organic light emitting layer is printed on the pixel electrode according to the line pattern by letterpress printing. It was. At this time, an anilox roll of 150 lines / inch and the resin relief printing plate of Example 1 were used. The thickness of the organic light emitting layer after printing and drying was 100 nm.

  Next, a cathode layer made of Ca and Al was formed on the organic light emitting layer by mask vapor deposition by a resistance overheating vapor deposition method in a line pattern orthogonal to the pixel electrode line pattern.

  Finally, in order to protect these organic EL element structural bodies from external oxygen and moisture, a glass cap and an adhesive were hermetically sealed to produce an element panel for an organic EL display of Example 1.

  In the peripheral part of the display part of the obtained panel, there are the extraction electrodes on the anode side and the cathode side connected to each pixel electrode, and the lighting display confirmation of the panel is performed by connecting these to the power source, and the light emission The state was checked.

<Example 2>
The resin relief printing plate of Example 2 has a two-step tapered shape in which the inclination angle of the portion close to the top is 85 degrees with respect to the substrate surface, and the inclination angle of the portion close to the bottom is 50 degrees with respect to the substrate surface. A relief having a convex portion is formed. The resin relief printing plate of Example 2 was prepared as follows.

  In the resin plate material, a photosensitive resin layer having a total thickness of 150 μm is formed on a steel substrate having a thickness of 200 μm. The photosensitive resin layer has a spherical shape of 100 μm on the side close to the substrate and is an acrylate ester type. A layer containing 10% by volume of organic fine particles and the same 50 μm on the side close to the surface layer were used as in Example 1 in which no spherical organic fine particles of an acrylate ester were used.

  The resin relief printing plate of Example 2 was formed from this resin plate material in the same manner as in Example 1 except that the gap during exposure was set to 50 μm and the exposure amount was set to 50 mJ. The relief depth of the resin relief printing plate of Example 2 was 100 μm or more.

  Using the resin relief printing plate of Example 2, an element panel for organic EL display of Example 2 was prepared in the same manner as Example 1.

<Example 3>
The resin relief printing plate of Example 3 has a two-step tapered shape in which the inclination angle of the portion close to the top is 90 degrees with respect to the substrate surface, and the inclination angle of the portion close to the bottom is 80 degrees with respect to the substrate surface. A relief having a convex portion is formed. The resin relief printing plate of Example 3 was prepared as follows.

  In the resin plate material, a photosensitive resin layer having a total thickness of 150 μm is formed on a steel substrate having a thickness of 200 μm. The photosensitive resin layer has a spherical shape of 100 μm on the side close to the substrate and is an acrylate ester type. A layer containing 3% of organic fine particles by volume and a layer having 50 μm on the side close to the surface layer containing no acrylate-based spherical organic fine particles was used.

  Forming the resin relief plate of Example 3 from this resin plate material was performed in the same manner as in Example 1. The relief depth of the resin relief printing plate of Example 3 was 100 μm or more.

  Using the resin relief printing plate of Example 3, an element panel for an organic EL display of Example 3 was produced in the same manner as in Example 1.

<Comparative Example 1>
The resin relief printing plate of Comparative Example 1 has a relief having a forward taper shaped projection having an inclination angle of 70 degrees with respect to the substrate from a resin plate material having a photosensitive resin layer consisting of a single layer having a uniform light scattering property. Formed. The resin relief printing of Comparative Example 1 was prepared as follows.

  First, the resin plate material has a photosensitive resin layer having a total thickness of 150 μm formed on a steel substrate having a thickness of 200 μm, and this photosensitive resin layer does not contain acrylate-based spherical organic fine particles at all. The one consisting only of one layer was used.

  To form the resin relief plate of Comparative Example 1 from this resin plate material, the film photomask of the negative pattern corresponding to the print pattern of the light emitting layer is brought into close contact with the exposed surface of the photosensitive resin layer of this resin plate material, The same procedure as in Example 1 was performed except that the scattered light exposure was performed with an exposure amount of 40 mJ. The relief depth of the resin relief printing plate of Comparative Example 1 was about 50 μm.

  Using the resin relief printing plate of Comparative Example 1, an element panel for organic EL display of Comparative Example 1 was prepared in the same manner as in Example 1.

<Comparative example 2>
The resin relief printing plate of Comparative Example 2 is a relief from a resin plate material having a photosensitive resin layer consisting of a single layer having a uniform light scattering property and having a non-tapered projection having an inclination angle of 90 degrees with respect to the substrate. Formed. The resin letterpress of Comparative Example 2 was prepared as follows.

  First, the resin plate material has a photosensitive resin layer having a total thickness of 150 μm formed on a steel substrate having a thickness of 200 μm, and this photosensitive resin layer does not contain acrylate-based spherical organic fine particles at all. The one consisting only of one layer was used.

  Forming the resin relief plate of Comparative Example 2 from this resin plate material was performed in the same manner as in Example 1. The relief depth of the resin relief printing plate of Comparative Example 2 was 100 μm or more.

  Using the resin relief printing plate of Comparative Example 2, an element panel for organic EL display of Comparative Example 2 was prepared in the same manner as in Example 1.

<Comparative Example 3>
The resin relief printing plate of Comparative Example 3 is a non-tapered tape having an inclination angle of 90 degrees with respect to the substrate only from the resin plate material having a photosensitive resin layer composed of two layers having different light scattering properties. A relief having a shape-shaped convex part was formed, and no relief was formed on the layer on the side close to the substrate. The resin relief printing plate of Comparative Example 3 was prepared as follows.

  First, the resin plate material has a photosensitive resin layer having a total thickness of 150 μm formed on a steel substrate having a thickness of 200 μm. The photosensitive resin layer has an acrylic ester-based side 100 μm on the side close to the substrate. A layer containing 15% of the spherical organic fine particles in a volume concentration and a layer having 50 μm on the side close to the surface layer containing no acrylate-based spherical organic fine particles were used.

Forming the resin relief plate of Comparative Example 3 from this resin plate material was performed in the same manner as in Example 1. The relief depth of the resin relief printing plate of Comparative Example 3 was about 50 μm. That is, no relief was formed in the layer on the side close to the substrate.

  Using the resin relief printing plate of Comparative Example 3, an element panel for organic EL display of Comparative Example 3 was produced in the same manner as in Example 1.

(Evaluation of resin letterpress)
Table 1 below shows the inclination angle of the relief protrusion, the relief depth, the relief depth evaluation, and the linearity evaluation of the lines for the resin relief plates of Examples 1 to 3 and Comparative Examples 1 to 3.

If the relief depth is too shallow, ink accumulates in the relief recesses and printability deteriorates. However, in the relief pattern of each example and each comparative example, it was judged that the relief depth of 100 μm or more could be secured. . Naturally, the linearity of the line is directly linked to the linearity of the printed matter. However, if the inclination angle of the relief convex part is perpendicular to the part close to the substrate, the strength of the relief convex part is weak, and resin is developed during development. The letterpress is easy to twist.

  As can be seen from Table 1, with respect to the relief depth, Examples 1 to 3 and Comparative Example 2 were 100 μm or more, which was satisfactory, but Comparative Examples 1 and 3 were shallow at 50 μm and judged to be defective. Further, with respect to the linearity of the line, only Comparative Example 2 was unsatisfactory because the development was finished and a relief line was observed.

(Evaluation of element panel for organic EL display)
Table 2 below shows the film thickness unevenness of the light emitting layer and the light emitting state of the panel for the organic EL display element panels of Examples 1 to 3 and Comparative Examples 1 to 3.

As can be seen from Table 2, according to the evaluation results of the resin relief printing, for the organic EL display element panel, each of Examples 1 to 3 was good in both the uneven thickness of the light emitting layer and the light emission state of the panel. Comparative Examples 1 to 3 were all poor.

The figure which illustrates the conventional resin letterpress. The figure which illustrates the resin letterpress of this invention. The figure which illustrates the resin plate material for creating the resin relief plate of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Base material 10 ... Relief convex part 20 ... Relief convex part 21 ... Part near the top 22 ... Part near the bottom 30 ... Photosensitive resin layer 31 ... Layer 32 near the surface layer ... Layer near the base material

Claims (5)

  A resin relief plate having a relief formed by exposing and developing a photosensitive resin layer laminated on a base material, the photosensitive resin layer comprising two layers having different light scattering properties, and close to the base material A resin relief printing plate, wherein the side layer is a layer having higher light scattering properties than the side layer close to the surface layer.   The resin relief printing plate according to claim 1, wherein the light-scattering layer of the photosensitive resin layer has a light scattering rate of 10% or more and 30% or less in the case of light having a wavelength of 360 nm. .   3. The resin relief printing plate according to claim 1, wherein the light-scattering layer of the photosensitive resin layer has a light scattering rate of 5% or less in the case of light having a wavelength of 360 nm.   The portion close to the top of the relief convex portion is formed of the layer having the lower light scattering property of the photosensitive resin layer, and the portion closer to the bottom of the relief convex portion is the layer having the higher light scattering property of the photosensitive resin layer. The inclination angle with respect to the base material surface of the portion near the top of the relief convex portion is between 85 degrees and 90 degrees, and the inclination angle with respect to the base material surface of the portion near the bottom of the relief convex portion is 50 degrees. The resin letterpress according to any one of claims 1 to 3, wherein the angle is between 80 and 80 degrees.   A method for producing an element panel for an organic EL display, comprising: patterning a light emitting layer of an organic EL element by a letterpress printing method using the resin letterpress according to any one of claims 1 to 4;