JP2005149823A - Laser heat transfer donor sheet for color organic el display, circuit board for color organic el display, and manufacturing method of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laser heat transfer donor sheet for color organic EL display reducing the number of processes and material cost for manufacturing a circuit board for color organic EL display, as well as an inexpensive circuit board for color organic EL display and its manufacturing method. <P>SOLUTION: The heat transfer donor sheet for color organic EL display has a photothermal conversion layer 13, and a stripe-shape organic material layer 3 having at least one organic luminous layer of R, G, and B formed on a support body 14, of which, the width of the organic material layer is broader than that of an electrode of a circuit board by 1.1 times or more and 5 times or less. On the circuit board for color organic EL display, the laser heat transfer donor sheet is superposed on the circuit board, on which a laser beam 17 is irradiated to have the organic material layer transferred on the electrode in a pixel shape. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a color organic EL display, and more particularly to a laser thermal transfer donor sheet for a color organic EL display, a circuit substrate for a color organic EL display, and a method for manufacturing the same, which are used for manufacturing a color organic EL display.

  A mask vapor deposition method has been proposed for forming pixels of a color organic EL display (see, for example, Patent Document 1). Or the inkjet method is proposed (for example, refer patent document 2). However, the mask vapor deposition method and the ink jet method are difficult to cope with an increase in size. In the mask vapor deposition method, there is a limit to the substrate size that can be input. In addition, the inkjet method has a problem that it takes time to produce an organic EL element on a large substrate. In order to solve these problems, a laser thermal transfer method was studied.

  However, in the conventional pixel formation using a laser thermal transfer donor sheet provided with an organic material layer capable of developing R, G, or B, each color is formed using an organic material layer capable of developing R, G, or B. A laser thermal transfer donor sheet is formed every time, and a transfer process is performed for each color (for example, see Patent Document 3).

That is, in the conventional laser thermal transfer donor sheet, each material of the organic material layer capable of coloring R, G, or B is provided on different sheets, and the transfer process is repeated for each material. In addition, since an organic material layer is provided on almost the entire surface of the sheet and transfer is performed in a desired size, there are many unused portions of the material.
JP-A-8-227276 Japanese Patent Laid-Open No. 10-12377 JP 2003-77658 A

  The present invention has been made in view of the above problems, and provides a laser thermal transfer donor sheet for a color organic EL display capable of reducing the number of steps for producing a circuit board for a color organic EL display and further reducing the material cost. It is an object to do.

  Another object of the present invention is to provide an inexpensive circuit board for color organic EL display using the laser thermal transfer donor sheet for color organic EL display, and a method for producing the circuit board.

  According to the present invention, a striped organic material layer having at least one organic light emitting layer of red (R), green (G), and blue (B) is formed on a support. This is a laser thermal transfer donor sheet for a color organic EL display.

  In the laser thermal transfer donor sheet for a color organic EL display according to the present invention, the width of the stripe-shaped organic material layer is 1.1 times or more and 5.0 or less than the width of the electrode of the circuit substrate for EL display. It is a laser thermal transfer donor sheet for a color organic EL display characterized by being.

  Further, according to the present invention, the laser thermal transfer donor sheet for a color organic EL display according to claim 1 or 2 is superimposed on an EL display circuit board, irradiated with laser light from the support side, and the organic material layer is A color organic EL display circuit board, which is transferred in a pixel shape onto an electrode of an EL display circuit board.

  The present invention also provides a laser thermal transfer donor sheet for a color organic EL display according to claim 1 or 2 that is superimposed on a circuit board for EL display, irradiated with laser light from the support side, A method for producing a circuit board for a color organic EL display, wherein the circuit board is transferred in a pixel shape onto electrodes of the circuit board for EL display.

  Manufacturing a laser thermal transfer donor sheet for color organic EL displays in which R, G, and B striped organic material layers are formed on a film substrate, and transferring the organic material layers for each color onto a circuit board for EL display By doing so, the production and transfer process of the thermal transfer donor sheet for the color organic EL display can be reduced to 1/3. In addition, the amount of material used can be reduced. Therefore, the manufacturing cost of the color organic EL display circuit board using the transfer method can be greatly reduced.

  A laser thermal transfer donor sheet for a color organic EL display and a circuit board for a color organic EL display according to the present invention will be described below based on one embodiment thereof.

  FIG. 1A is a plan view from the upper surface of an embodiment of a laser thermal transfer donor sheet for a color organic EL display according to the present invention, and FIG. 1B is a cross-sectional view in a direction parallel to the stripe of a stripe-shaped organic material layer. , (C) is a cross-sectional view in the perpendicular direction. Moreover, (d) is sectional drawing which expands and shows the perpendicular direction in the state in which the cover film (15) was bonded together.

  As shown in FIGS. 1A to 1C, a laser thermal transfer donor sheet for a color organic EL display according to the present invention has a photothermal conversion layer (13), a stripe on a film substrate (14) as a support. A shaped organic material layer (3) is formed. FIG. 2 is a cross-sectional view perpendicular to the stripes in an example of a circuit board for a color organic EL display manufactured using the laser thermal transfer donor sheet for a color organic EL display.

  As shown in FIG. 2, the color organic EL display circuit board has the organic material layer (3) of the laser thermal transfer donor sheet for the color organic EL display on the first electrode (2) of the EL display circuit board (20). It is formed in a pixel shape, and subsequently, a protective layer (4) and a second electrode (5) are formed on the entire surface.

  The EL display circuit substrate (20) is obtained by sequentially forming a TFT (6), a first electrode (2), and a planarizing layer (10) on a substrate (1).

Below, each layer which comprises the laser thermal transfer donor sheet for color organic EL displays is explained in full detail.
(Support)
The support of the present invention is a film substrate, and a substrate made of a transparent polymer can be used. Examples of the transparent polymer include polyethylene terephthalate, polyether sulfone, polycarbonate, polyacryl, polyester, polyethylene, polyepoxy, polystyrene, and the like, and polyethylene terephthalate and polycarbonate are most preferable from the characteristics of the film. Furthermore, it is preferable to use a film substrate processed with a barrier film in order to maintain the water vapor barrier property.
(Photothermal conversion layer)
The photothermal conversion layer is a functional film that absorbs light and generates heat with high efficiency. Examples of such a film include carbon black, graphite, infrared dye, aluminum, and a metal film made of an oxide / sulfide thereof. The film can be used by dispersing in a polymer material and forming a thin film. It is also possible to stack a release layer having a release function. The release layer is a layer for receiving the heat generated by the photothermal conversion layer to release the transfer layer, and examples thereof include poly α-methylstyrene.
(R, G, and B organic light emitting layers)
The organic light emitting layers of R, G, and B make coating liquids of organic light emitting materials that can emit light to R, G, and B. For example, spinless coating method, ink jet method, dip coating method, doctor blade method, ejection It is possible to form a film by a wet process such as a coating method, a spray coating method, a relief printing method, an intaglio printing method, a screen printing method, or a micro gravure coating method.

  In addition, the film can be formed by a conventional method. For example, the film can be formed by a drive process such as a vacuum evaporation method, an EB method, an MBE method, or a sputtering method. However, considering the cost of manufacturing the laser thermal transfer donor sheet, a process using a spinless coating method and an ink jet method is preferable.

  The coating liquid of the organic light emitting material capable of emitting light to R, G, and B is a solution containing at least each organic light emitting material, and may contain one kind or many kinds of organic light emitting materials. Furthermore, you may contain the resin for binding. Moreover, a leveling agent, a light emission assisting agent, a charge transporting material, an additive, or the like may be added as an improving agent such as a coating liquid coating performance.

  As the organic light emitting material, a known light emitting material for an organic EL element can be used.

  Examples of the low-molecular light emitting material include aromatic dimethylidene compounds such as 4,4′-bis (2,2′-diphenylvinyl) -biphenyl (DPVBi), 5-methyl-2- [2- [4- (5 Oxadiazole compounds such as -methyl-2-benzoxazolyl) phenyl] vinyl] benzoxazole, 3- (4-biphenylyl) -4-phenyl-5-t-butylphenyl-1,2,4-triazole Fluorescence of triazole derivatives such as (TAZ), styrylbenzene compounds such as 1,4-bis (2-methylstyryl) benzene, thiopyrazine dioxide derivatives, benzoquinone derivatives, naphthoquinone derivatives, anthraquinone derivatives, diphenoquinone derivatives, fluorenone derivatives, etc. Organic material, azomethine zinc complex, (8-hydroxyquinolinato) , And the like aluminum complex (Alq3) fluorescent organic metal compound such.

  Examples of the binding resin include polycarbonate and polyester. The solvent may be any solvent that can dissolve or disperse the light emitting material, and examples thereof include pure water, methanol, ethanol, THF, chloroform, toluene, xylene, trimethylbenzene, and a mixed solution thereof. .

On the other hand, as a polymer light-emitting material, poly [2,5-bis- [2- (N, N, N-triethylammonium) ethoxy] -1,4-phenyl-alt-1,4-phenyllene] dipromide ( PPP-NEt3 +), poly (2-decyloxy-1,4-phenylene) DO-PPP, poly [5-methoxy- (2-propanoxysulfonide) -1,4-phenylenevinylene] (MPS-PPV), Poly [2,5-bis- (hexyloxy) -1,4-phenylene- (1-cyanovinylene)] (CN-PPV), poly [2- (2′-ethylhexyloxy) -5-methoxy-1, 4-phenylene vinylene] (MEH-PPV), (poly (9,9-dioctylfluorene)) (PDAF), and the like. Examples of the precursor of the polymer light-emitting material include For example, a PPV precursor, a PNV precursor, a PPP precursor, etc. can be mentioned.
(Organic material layer)
The organic material layer may be a single layer structure or a multilayer structure, and examples thereof include the following configurations.
1. 1. Organic light emitting layer 2. hole transport layer / organic light emitting layer 3. Organic light emitting layer / electron transport layer 4. hole transport layer / organic light emitting layer / electron transport layer 5. Hole injection layer / hole transport layer / organic light emitting layer / electron transport layer Hole injection layer / hole transport layer / organic light emitting layer / blocking layer / electron transport layer (charge transport layer (hole injection layer, hole transport layer, and electron transport layer))
The hole injection layer, the hole transport layer, and the electron transport layer may be a single layer or a multilayer structure. Here, the charge transport layer can be formed by a conventional method. For example, the charge transport material is directly formed by a dry process such as a vacuum evaporation method, an EB method, an MBE method, or a sputtering method. Is possible.

  Spin coating method, dip coating method, doctor blade method, discharge coating method, spray coating method, ink jet method, letterpress printing method, intaglio printing method, screen printing method, microgravure coating method, using charge transport layer forming coating solution It is also possible to form a film by a wet process such as.

  The coating solution for forming a charge transport layer is a solution containing at least a charge transport material, may contain one or more kinds of charge transport materials, and may further contain a binding resin. . Moreover, a leveling agent, other additives, etc. may be added.

  Here, as the charge transport material, known charge transport materials for organic EL elements and organic photoconductors can be used.

  Examples of the hole transport material include inorganic p-type semiconductor materials, porphyrin compounds, N, N′-di (naphthalen-1-yl) -N, N′-diphenyl-benzidine (NPD), N, N′-bis- ( Low molecular weight materials such as aromatic tertiary amine compounds, quinacridone compounds, styrylamine compounds such as 3-methylphenyl) 1 N, N′-bis- (phenyl) -benzidine (TPD), hydrazone compounds, polyaniline (PANI), 3,4-polyethylenedioxythiophene / polystyrene sulfonate (PEDT / PSS), poly [triphenylamine derivative] (Poly-TPD), poly (p-naphthalene vinylene) precursor (Pre-PNV) , Poly (p-phenylene vinylene) precursor (Pre-PPV), polyvinylcarbazole (PVCz), etc. Examples thereof include molecular materials or polymer material precursors.

  On the other hand, as an electron transport material, low molecular weight materials such as inorganic n-type semiconductor materials, anthraquinone derivatives, oxadiazole derivatives, diphenoquinone derivatives, thiopyrazine dioxide derivatives, triazole derivatives, naphthoquinone derivatives, benzoquinone derivatives, fluorenone derivatives, and poly [High molecular materials such as oxadiazole [(Poly-OXZ)].

Examples of the binding resin include polycarbonate, polyester, and the like, as in the case of a coating liquid of an organic light emitting material capable of emitting light to R, G, and B. The solvent may be any solvent that can dissolve or disperse the light emitting material, and examples thereof include pure water, methanol, ethanol, THF, chloroform, toluene, xylene, trimethylbenzene, and a mixed solution thereof. . .

  The charge blocking layer may be a single layer or a multilayer structure. The coating solution for forming a charge blocking layer is a solution containing at least one or more kinds of charge blocking materials, and may further contain a binding resin. Further, a leveling agent or the like may be added.

  As the charge blocking material, known charge blocking materials for organic EL elements can be used, and examples include 2,9-dimethyl-1,10-phenanthroline and 4,7-diphenyl-1,10-phenanthroline. Examples of the binding resin include polycarbonate and polyester as well as the hole transport material and the electron transport material. The solvent may be any solvent that can dissolve or disperse the charge blocking material, and examples thereof include pure water, methanol, ethanol, THF, chloroform, xylene, and trimethylbenzene.

  For the purpose of protecting the organic material layer on the support, it is desirable to form a cover film with a film substrate processed with a barrier film in order to maintain water vapor barrier properties. This cover film is peeled off immediately before the transfer process.

  Further, the present invention is characterized in that the width of the stripe-shaped organic material layer of each color is 1.1 times or more and 5.0 or less than the width of the electrode of the EL display circuit board.

  Here, the width of the stripe-shaped organic material layer of the laser thermal transfer donor sheet means a width sufficient to form the organic EL elements (11) of the respective colors. When the width (W1) of the organic material layer is less than 1.1 times the width (W2) of the first electrode (2) in FIG. 2, alignment accuracy in forming the organic EL element is required. The throughput in the process is reduced.

  Further, when the width is 5 times or more, the amount of the organic material layer provided on the laser thermal transfer donor sheet increases, and the material cost increases. Preferably, the width (W2) of the first electrode (2) is 1.7 times or more and 3 times or less.

  3 (a) to 3 (c) and FIGS. 4 (a) to 4 (c) show steps of manufacturing a circuit substrate for a color organic EL display using the laser thermal transfer donor sheet for a color organic EL display according to the present invention. It is explanatory drawing.

  The above-mentioned laser thermal transfer donor sheet for color organic EL display is laminated on the surface of the organic material layer to the EL display circuit substrate (20) in which the TFT, the first electrode, and the planarization layer have already been formed on the substrate. Laser light is irradiated from the substrate side.

  At this time, following the pixel shape of the first electrode while detecting the first electrode so that the organic material layer is transferred onto the pixel shape of the first electrode (2) on the first electrode (2). Laser light is irradiated (FIGS. 3A to 3C).

  The laser (16) used for the transfer is not particularly limited with respect to the type of laser light or the wavelength of irradiation, and a semiconductor laser, a YAG laser, or the like is preferable.

  Here, since the width (W1) of the stripe-shaped organic material layer formed on the laser thermal transfer donor sheet is wider than the width (W2) of the first electrode on the circuit board for EL display, the detection accuracy needs to be strict. There is no.

  The laser beam (17) is irradiated, for example, following the first electrode of the organic EL element that emits red light and irradiating the region corresponding to the pixel shape of the first electrode (FIG. 3C). Next, the region corresponding to the pixel shape of the first electrode is irradiated following the first electrode of the adjacent organic EL element that emits green light (FIG. 4A). A plurality of lasers (16) may be used.

  In this way, when the laser light is sequentially irradiated and the irradiation of the entire surface of the circuit board for EL display is completed, the laser thermal transfer donor sheet for color organic EL display is peeled off, and the organic material layer (3) is removed. It transfers to a pixel form on the 1st electrode (2) of the circuit board (20) for EL displays (FIG.4 (b)).

  After the transfer of the organic material layer (3), a protective film (4) is formed on the entire surface of the EL display circuit board (20). Examples of the forming method include ordinary means such as sputtering and CVD. Next, a second electrode (5) is formed (FIG. 4C).

As the second electrode, a conventional electrode material can be used, and a metal (Au, Pt, Ni, etc.) having a high work function, a transparent electrode (ITO), SnO ₂ or the like can be used. Further, these materials can be formed by EB, sputtering, resistance heating vapor deposition, or the like.

  The protective film (4) can be formed after the second electrode is formed.

  FIG. 5 shows a laser thermal transfer donor sheet for a color organic EL display according to the present invention, the organic material layer (3) of which is bonded to the EL display circuit board (20), and the organic material layer is first formed by laser light. It is a top view which shows an example of the laser thermal transfer donor sheet | seat for color organic EL displays at the time of peeling from the circuit board for EL displays (20) after irradiating the pixel shape of an electrode.

  In this example of the laser thermal transfer donor sheet, R, G, and B striped organic material layers are repeatedly formed on the film substrate in the horizontal direction and the width direction of the stripe in FIG. The hatched portion (51) represents the organic material layer remaining on the film substrate without being transferred, and the hatched square portion (52) is transferred onto the first electrode (2). Represents an area.

  On the other hand, FIG. 6 is a plan view of an example of a conventional laser thermal transfer donor sheet. Similarly, after the organic material layer is irradiated onto the pixel shape of the first electrode by laser light, the EL display circuit board (20) is used. It is a thing at the time of peeling.

  In the conventional laser thermal transfer donor sheet, the organic material layers of R, G, or B are formed on different sheets. At the time of transfer, R, G, or B is transferred for each different laser thermal transfer donor sheet.

  Therefore, as indicated by the oblique lines in FIG. 6, the area of the organic material layer (61) remaining on the film substrate without being transferred is large. FIG. 6 shows a red (R) laser thermal transfer donor sheet, but the same applies to G and B.

  Hereinafter, the present invention will be described in detail with reference to examples. However, the present invention is not limited to the embodiments.

  A 500 mm wide sheet roll of about 100 μm thick polyethylene terephthalate was used as the film substrate. This film base material was coated with a thermosetting epoxy resin in which carbon fine particles were mixed so as to have a film thickness of about 5 μm after curing, and cured to form a photothermal conversion layer. Next, a release layer that was easily peeled off by heating was coated so that the film thickness after drying was about 1 μm. In addition, the surface of the used polyethylene terephthalate was subjected to a barrier treatment for preventing permeation of moisture.

Next, using a micro gravure coater, the hole transport layer forming coating solution was dried and then applied to a film thickness of about 20 nm to form a hole transport layer. Furthermore, a coating liquid for forming an organic light emitting layer was applied thereon with an ink jet printer so as to have a film thickness of about 50 nm, thereby forming a striped organic light emitting layer. In addition, the width | variety of each organic light emitting layer which light-emits R, G, and B was 100 micrometers.

  Next, the sheet roll was heated in a nitrogen atmosphere at about 110 ° C. for 1 hour to remove the residual solvent. Finally, a 25-μm thick polyethylene terephthalate film with a release layer formed so that the barrier layer that prevents moisture permeation and the protective substrate are easier to peel off than the organic light-emitting layer is laminated as a protective substrate to produce a laser thermal transfer donor sheet did. That is, this laser thermal transfer donor sheet is composed of a hole transport layer as an organic material layer and an organic light emitting layer in the form of stripes of R, G, and B.

The protective substrate polyethylene terephthalate is peeled off from the laser thermal transfer donor sheet, and the laser thermal transfer donor sheet and the organic EL display circuit board are formed so that each colored stripe covers the 35 μm wide first electrode on the organic EL display circuit board. After being set and pressed to a pressure of about 2 × 10 ⁻³ Pa using a roller, the desired position was scanned with a YAG laser to form an organic material layer with a width of 66 μm for each color. Then, the laser thermal transfer donor sheet was peeled from the EL display circuit board.

  Next, a barrier layer having a thickness of about 150 nm was formed on the EL display circuit substrate onto which the organic material layer had been transferred, using CVD to prevent moisture from passing therethrough. Further, a second electrode (transparent electrode) of about 50 nm was formed on the EL display circuit substrate with a barrier layer by sputtering.

  By forming the organic light emitting layer of the laser thermal transfer donor sheet into a striped organic light emitting layer of three colors, the laser thermal transfer donor sheet could be combined into one roll. Moreover, the transfer process of the organic material layer to the circuit board for EL displays could be reduced to one time. Furthermore, the amount of discarded organic material layers could be reduced.

  A 500 mm wide sheet roll of about 100 μm thick polyethylene terephthalate was used as the film substrate. This film base material was coated with a thermosetting epoxy resin in which carbon fine particles were mixed so as to have a film thickness of about 5 μm after curing, and cured to form a photothermal conversion layer. Next, a release layer that was easily peeled off by heating was coated so that the film thickness after drying was about 1 μm. In addition, the surface of the used polyethylene terephthalate was subjected to a barrier treatment for preventing permeation of moisture.

  Next, using a micro gravure coater, the hole transport layer forming coating solution was dried and applied to a film thickness of about 20 nm to form a hole transport layer. Furthermore, a coating liquid for forming an organic light emitting layer was applied thereon with an ink jet printer so as to have a film thickness of about 50 nm, thereby forming a striped organic light emitting layer. R and G each have a stripe width of 70 μm, and B has a stripe width of 120 μm.

  Next, the sheet roll was heated in a nitrogen atmosphere at about 110 ° C. for 1 hour to remove the residual solvent. Finally, a 25-μm thick polyethylene terephthalate film with a release layer formed so that the barrier layer that prevents moisture permeation and the protective substrate are easier to peel off than the organic light-emitting layer is laminated as a protective substrate to produce a laser thermal transfer donor sheet did. That is, this laser thermal transfer donor sheet is composed of a hole transport layer and an organic light emitting layer as an organic material layer.

Remove the protective polyethylene terephthalate from the laser thermal transfer donor sheet and set the laser thermal transfer donor sheet and the EL display circuit board so that each colored stripe covers the 35 μm wide first electrode on the EL display circuit board. , Using a roller to press and adhere to about 2 × 10 ⁻³ Pa, and then scanning a desired position with a YAG laser to form an organic material layer with R and G being 40 μm each and B being 90 μm . The laser thermal transfer donor sheet was peeled from the EL display circuit board.

  Next, on the EL display circuit board on which the organic material layer was formed, a barrier layer of about 150 nm for preventing moisture permeation was formed using CVD. Further, a second electrode (transparent electrode) of about 50 nm was formed on the EL display circuit substrate with a barrier layer by sputtering.

  By forming the organic color-developing layer of the laser thermal transfer donor sheet in the organic light emitting layer of three different stripe widths, the laser thermal transfer donor sheet is combined into one roll even if it is a circuit board for EL display having different color opening areas. I was able to. Moreover, the transfer process of the organic layer to the circuit board for EL displays could be reduced to one time. Furthermore, the amount of discarded organic material layers could be reduced.

  A 500 mm wide sheet roll of about 100 μm thick polyethylene terephthalate was used as the film substrate. This film base material was coated with a thermosetting epoxy resin in which carbon fine particles were mixed so as to have a film thickness of about 5 μm after curing, and cured to form a photothermal conversion layer. Next, a release layer that was easily peeled off by heating was coated so that the film thickness after drying was about 1 μm. In addition, the surface of the used polyethylene terephthalate was subjected to a barrier treatment for preventing permeation of moisture.

  Next, using a micro gravure coater, the hole transport layer forming coating solution was dried and then applied to a film thickness of about 20 nm to form a hole transport layer. Further, a red organic light emitting layer forming coating solution was applied thereon with a micro gravure coater so that the film thickness was about 50 nm, and a red organic light emitting layer was formed on the entire surface of the sheet with a uniform film thickness.

  Next, the sheet roll was heated at about 110 ° C. for 1 hour in a nitrogen atmosphere to remove the residual solvent. Finally, a 25-μm thick polyethylene terephthalate film with a release layer formed so that the barrier layer that prevents moisture permeation and the protective substrate are easier to peel off than the organic light-emitting layer is laminated as a protective substrate to produce a laser thermal transfer donor sheet did. That is, this laser thermal transfer donor sheet is composed of a hole transport layer and a red organic light emitting layer as an organic material layer.

  Similarly, a sheet roll of 500 mm width having a thickness of about 100 μm polyethylene terephthalate was used as a film substrate. This film base material was coated with a thermosetting epoxy resin in which carbon fine particles were mixed so as to have a film thickness of about 5 μm after curing, and cured to form a photothermal conversion layer. Next, a release layer that was easily peeled off by heating was coated so that the film thickness after drying was about 1 μm. In addition, the surface of the used polyethylene terephthalate was subjected to a barrier treatment for preventing permeation of moisture.

  Next, using a micro gravure coater, the hole transport layer forming coating solution was dried and then applied to a film thickness of about 20 nm to form a hole transport layer. Further, a green organic light emitting layer forming coating solution was applied thereon with a micro gravure coater so that the film thickness was about 50 nm, and a green organic light emitting layer was formed with a uniform film thickness on the entire surface of the sheet.

  Next, the sheet roll was heated at about 110 ° C. for 1 hour in a nitrogen atmosphere to remove the residual solvent. Finally, a laser thermal transfer donor sheet was prepared by laminating 25 μm-thick polyethylene terephthalate on which a release layer was formed so that the barrier layer for preventing moisture permeation and the protective substrate were more easily peeled off from the light emitting layer as a protective substrate. . That is, this laser thermal transfer donor sheet is composed of a hole transport layer and a green organic light emitting layer as organic material layers.

Similarly, a sheet roll of 500 mm width having a thickness of about 100 μm polyethylene terephthalate was used as a film substrate. This film base material was coated with a thermosetting epoxy resin in which carbon fine particles were mixed so as to have a film thickness of about 5 μm after curing, and cured to form a photothermal conversion layer. Next, a release layer that was easily peeled off by heating was coated so that the film thickness after drying was about 1 μm. In addition, the surface of the used polyethylene terephthalate was subjected to a barrier treatment for preventing permeation of moisture.

  Next, using a micro gravure coater, the hole transport layer forming coating solution was dried and then applied to a film thickness of about 20 nm to form a hole transport layer. Further, a blue organic light emitting layer forming coating solution was applied thereon with a micro gravure coater so that the film thickness was about 50 nm, and a blue organic light emitting layer was formed on the entire surface of the sheet with a uniform film thickness.

  Next, the sheet roll was heated at about 110 ° C. for 1 hour in a nitrogen atmosphere to remove the residual solvent. Finally, a 25-μm thick polyethylene terephthalate film with a release layer formed so that the barrier layer that prevents moisture permeation and the protective substrate are easier to peel off than the organic light-emitting layer is laminated as a protective substrate to produce a laser thermal transfer donor sheet did. That is, this laser thermal transfer donor sheet is composed of a hole transport layer and a blue organic light emitting layer as organic material layers.

Peel off the protective polyethylene terephthalate from the red laser thermal transfer donor sheet, set the circuit board for EL display, press it to about 2 × 10 ^-3 Pa using a roller, and then attach it with YAG laser. The blue organic material layer was formed with a width of 66 μm. Then, the laser thermal transfer donor sheet was peeled from the EL display circuit board.

Then, peeling the polyethylene terephthalate of the protective substrate from the green laser thermal transfer donor sheet, setting the circuit substrate for an organic EL display that forms a red organic material layer, about 2 × 10 ^-3 Pa using a roller After pressurizing and adhering, a desired position was scanned with a YAG laser to form a green organic material layer having a width of 66 μm. Then, the laser thermal transfer donor sheet was peeled from the EL display circuit board.

Next, the protective substrate polyethylene terephthalate is peeled off from the blue laser thermal transfer donor sheet, and the EL display circuit board on which the red organic material layer and the green organic material layer are formed is set. After pressurizing to 10 ⁻³ Pa and bringing it into close contact, a desired position was scanned with a YAG laser to form an organic material layer having a B width of 66 μm. Then, the laser thermal transfer donor sheet was peeled from the EL display circuit board.

  Next, on the EL display circuit board on which the organic material layer was formed, a barrier layer of about 150 nm for preventing moisture permeation was formed using CVD. Further, a second electrode (transparent electrode) of about 50 nm was formed on the EL display circuit substrate with a barrier layer by sputtering.

  The laser thermal transfer donor sheet was prepared in each color, and each color was transferred sequentially to form an organic material layer. Therefore, the amount of material used, the transfer process and the remaining amount of the organic material layer were also included in the striped laser thermal transfer donor sheet according to the present invention. Compared to the high cost.

(A) is a top view from the upper surface of one Example of the laser thermal transfer donor sheet | seat for color organic EL displays by this invention.

  (B) is sectional drawing of a parallel direction with the stripe of an organic material layer.

  (C) is a cross-sectional view perpendicular to the stripe.

(D) is sectional drawing which expands and shows the perpendicular direction in the state in which the cover film was bonded together.
It is sectional drawing of the direction orthogonal to the stripe in an example of the circuit board for color organic EL displays by this invention. (A)-(c) is explanatory drawing of the process of manufacturing the circuit board for color organic EL displays by this invention. (A)-(c) is explanatory drawing of the process of manufacturing the circuit board for color organic EL displays by this invention. It is a top view which shows an example of the laser thermal transfer donor sheet for color organic EL displays at the time of the laser thermal transfer donor sheet for color organic EL displays by this invention peeling from the circuit board for EL displays. It is a top view at the time of the organic material layer of the conventional laser thermal transfer donor sheet having been peeled from the circuit board for EL display.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Substrate 2 ... First electrode 3 ... Organic material layer 4 ... Protective layer 5 ... Second electrode 6 ... TFT
DESCRIPTION OF SYMBOLS 10 ... Planarization layer 11 ... Organic EL element 13 ... Photothermal conversion layer 14 ... Film base material (support body)
15 ... Cover film 16 ... Laser 17 ... Laser light 20 ... EL display circuit board 51, 61 ... Remaining organic material layers 52, 62 ... on the first electrode Transferred area W1 Width of organic material layer W2 Width of first electrode

Claims (4)

  A color comprising a light-to-heat conversion layer and a stripe-shaped organic material layer having at least one organic light emitting layer of red (R), green (G), and blue (B) formed on a support. Laser thermal transfer donor sheet for organic EL displays.   2. The laser thermal transfer donor for a color organic EL display according to claim 1, wherein the width of the stripe-shaped organic material layer is 1.1 times or more and 5.0 or less of the width of the electrode of the EL display circuit board. Sheet.   The laser thermal transfer donor sheet for a color organic EL display according to claim 1 or 2 is superimposed on an EL display circuit board, irradiated with laser light from the support side, and an organic material layer is formed on the EL display circuit board. A circuit board for a color organic EL display, which is transferred onto an electrode in a pixel form.   The laser thermal transfer donor sheet for a color organic EL display according to claim 1 or 2 is superimposed on an EL display circuit board, irradiated with laser light from the support side, and an organic material layer is applied to the EL display circuit board. A method of manufacturing a circuit substrate for a color organic EL display, wherein the substrate is transferred onto an electrode in a pixel shape.

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