TWI773795B - display device - Google Patents

Abstract

The display device includes a first substrate, a second substrate arranged to face the first substrate, a first transparent electrode arranged between the first substrate and the second substrate on the side of the first substrate, a second transparent electrode arranged between the first substrate and the second substrate on the side of the second substrate, a reflective layer between the first substrate and the first transparent electrode, and a second transparent electrode arranged between the first substrate and the second substrate A liquid crystal layer having a light-adjusting function between the first transparent electrode and the second transparent electrode, and a color-emitting layer disposed between the first transparent electrode and the reflective layer, and extending from the second substrate The color of the incident light incident on the side and the color of the outgoing light reflected by the reflective layer and emitted from the second substrate side are different from each other.

Description

display device

The present invention relates to a display device and a manufacturing method of the display device.

Conventionally, a liquid crystal display device using a phosphor and a guest-host type liquid crystal layer has been proposed (for example, Patent Document 1).

[Prior Art Literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 8-29787

However, as in the prior art, when a phosphor is used, the half-value width of the spectrum is relatively wide, so the color is blurred and there is a problem that the display quality is not excellent.

In addition, as in the prior art, when a guest-host liquid crystal layer is used, the dichroic ratio of the dichroic dye is not sufficiently high, and the contrast ratio is not sufficiently high. In order to increase the contrast ratio, it is necessary to increase the dye concentration, but if the dye concentration is increased, the transmittance decreases and the brightness decreases.

One embodiment of the present invention is intended to solve the above-mentioned problems associated with the related art, and an object thereof is to provide a display device having a higher display quality.

According to an embodiment of the present invention, there is provided a display device including a first substrate, a second substrate arranged to face the first substrate, and a first substrate arranged between the first substrate and the second substrate on the side of the first substrate 1 transparent electrode, a second transparent electrode arranged between the first substrate and the second substrate on the side of the second substrate, a reflective layer between the first substrate and the first transparent electrode, arranged between the first transparent electrode and the second transparent electrode A liquid crystal layer having a light-adjusting function between the electrodes, and a color-emitting layer disposed between the first transparent electrode and the reflective layer, and the color of incident light incident from the second substrate side is related to the color of the incident light reflected by the reflective layer and The colors of the light emitted from the second substrate side are different from each other.

According to an embodiment of the present invention, there is provided a display device including a first substrate, a second substrate arranged to face the first substrate, and a first substrate arranged between the first substrate and the second substrate on the side of the first substrate 1 transparent electrode, a second transparent electrode arranged between the first substrate and the second substrate on the side of the second substrate, a reflective layer between the first substrate and the first transparent electrode, arranged between the first transparent electrode and the second transparent electrode between the electrodes, a layer having a chargeable particle or liquid and having a dimming function, and a color-emitting layer disposed between the first transparent electrode and the reflective layer, and the color of incident light incident from the second substrate side, The colors of the outgoing light reflected by the reflective layer and emitted from the second substrate side are different from each other.

According to an embodiment of the present invention, there is provided a display device including a first substrate, a second substrate arranged to face the first substrate, and a first substrate arranged between the first substrate and the second substrate on the side of the first substrate a transparent electrode, a second transparent electrode disposed on the second substrate side between the first substrate and the second substrate, the first substrate and the A reflective layer between the first transparent electrodes, a layer disposed between the first transparent electrode and the second transparent electrode and containing charged particles or liquid and having a dimming function, and a layer disposed between the first transparent electrode and the reflective layer The color-emitting layer in between, and the color of the incident light incident from the second substrate side and the color of the outgoing light reflected by the reflective layer and emitted from the second substrate side are different from each other.

According to one embodiment of the present invention, a display device having excellent display quality can be provided.

According to an embodiment of the present invention, a display device with excellent display quality can be provided by combining a layer having a light-adjusting function with a color-emitting layer.

1: Display device

10: Pixel

11: The first substrate

13: Gate electrode

15: Gate insulating film

17: Semiconductor layer

19: source electrode

21: drain electrode

20: Thin Film Transistor

23: Passivation layer

25: Embankment Layer

26: Sidewall

27: Reflective layer

29: wiring layer

31: Scattering layer

33: Hair Color Layer

34: outer coating

35: 1st transparent electrode

37: Black matrix. spacer

39: The first alignment film

40: Dimming layer

41: Second alignment film

43: Second transparent electrode

45: Second substrate

46: Liquid crystal layer

47: Liquid crystal molecules

49: Dichroic Pigments

51: Hydrophobic membrane

53: 1st partition wall material

55: Second partition wall material

57: Liquid 1

59: 2nd fluid

104: Pixel area

108, 109: Gate side drive circuit

112: source side drive circuit

114: Flexible Printed Circuit Substrates

116: Integrated Circuits (ICs)

L _i : Incident light

L _o : outgoing light

FIG. 1 is a schematic plan view showing the configuration of a display device according to an embodiment of the present invention.

2 is a schematic cross-sectional view showing the configuration of a display device according to an embodiment of the present invention.

3 is a schematic cross-sectional view for explaining a step of a method for manufacturing a display device according to an embodiment of the present invention.

4 is a schematic cross-sectional view for explaining a step of a method for manufacturing a display device according to an embodiment of the present invention.

5 is a schematic cross-sectional view for explaining a step of a method of manufacturing a display device according to an embodiment of the present invention.

6 is a schematic cross-sectional view for explaining a step of a method of manufacturing a display device according to an embodiment of the present invention.

7 is a schematic cross-sectional view for explaining a step of a method of manufacturing a display device according to an embodiment of the present invention.

8 is a schematic cross-sectional view for explaining a step of a method of manufacturing a display device according to an embodiment of the present invention.

FIG. 9 is a schematic cross-sectional view for explaining a step of a method of manufacturing a display device according to an embodiment of the present invention.

10 is a schematic cross-sectional view for explaining a step of a method for manufacturing a display device according to an embodiment of the present invention.

11 is a schematic cross-sectional view showing the configuration of a display device according to another embodiment of the present invention.

12 is a schematic cross-sectional view showing the configuration of the display device according to the embodiment of the present invention in a first state.

13 is a schematic cross-sectional view showing the configuration of the display device according to the embodiment of the present invention in a second state.

14 is a schematic cross-sectional view for explaining a step of a method of manufacturing a display device according to an embodiment of the present invention.

15 is a schematic cross-sectional view for explaining a step of a method of manufacturing a display device according to an embodiment of the present invention.

16 is a schematic cross-sectional view for explaining a step of a method of manufacturing a display device according to an embodiment of the present invention.

17 is a schematic cross-sectional view showing a configuration of a display device according to another embodiment of the present invention in a voltage-off state.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. The embodiment shown below is an example of the embodiment of the present invention, and the present invention is not limited to these embodiments. In addition, in order to demonstrate more clearly, in some cases, the drawing schematically shows the width, thickness, shape, etc. of each part compared with the actual state. However, the schematic drawing is merely an example, and does not limit the interpretation of the present invention.

In addition, in the drawings referred to in this embodiment, the same parts or parts having the same functions are denoted by the same symbols or similar symbols (only symbols such as A and B are denoted after the numerals), and the repetition thereof is omitted. situation described.

In this specification, the term "on" includes not only the case where it is arranged so as to be directly in contact with a certain object or region, but also the case where it is arranged with other objects or regions therebetween. The same applies to the term "under". In addition, terms such as "up" and "down" indicate a relative upper-lower relationship between objects or regions, and do not mean an absolute upper-lower relationship.

<First Embodiment>

[Configuration of Display Device]

A display device according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2 . FIG. 1 is a schematic plan view showing the configuration of a display device according to an embodiment of the present invention.

The display device 1 includes: a first substrate 11 , a pixel region 104 , a gate-side driver circuit 108 , a gate-side driver circuit 109 , a source-side driver circuit 112 , a flexible printed circuit (FPC) 114 , and an active Integrated Circuit (IC) 116 .

A pixel region 104 , a gate-side driver circuit 108 , a gate-side driver circuit 109 , and a source-side driver circuit 112 are formed on the first substrate 11 . The flexible printed circuit board 114 is connected to the first board 11 . An integrated circuit (IC) 116 is disposed on the flexible printed circuit substrate 114 .

The pixel area 104 includes a plurality of pixels 10 . The plurality of pixels 10 are arranged along a direction and a direction intersecting the one direction. The number of arrangements of the plurality of pixels 10 is arbitrary. For example, m pixels 10 are arranged in the X direction and n pixels 10 are arranged in the Y direction. m and n are each independently a natural number larger than 1. The pixel area 104 is a display area. Each of the pixels 10 has a display element, and the display element includes a liquid crystal element.

For example, a display element corresponding to the three primary colors of red (R), green (G), and blue (B) may be provided in each of the three pixels. A full-color liquid crystal display device can be provided by supplying 256-level voltage or current to each pixel. In addition, the arrangement of the plurality of pixels 10 is not limited. For example, a stripe arrangement, a delta arrangement, or the like may be employed.

The flexible printed circuit board 114 has a role of supplying video signals, timing signals for controlling circuit operation, and power to the gate-side driver circuit 108 , the gate-side driver circuit 109 , and the source-side driver circuit 112 . The flexible printed circuit substrate 114 may use a flexible printed circuit (FPC). When video signals and control circuits operate Sequence signals, power supplies, and the like are supplied from an external circuit to the gate-side driver circuit 108 , the gate-side driver circuit 109 , and the source-side driver circuit 112 via the flexible printed circuit board 114 .

The gate-side driver circuit 108 , the gate-side driver circuit 109 , and the source-side driver circuit 112 have the functions of driving each pixel 10 using a supplied video signal, a timing signal for controlling the operation of the circuit, a power supply, and the like to display in the pixel area 104 The role of images.

All of the gate-side driver circuit 108 , the gate-side driver circuit 109 , and the source-side driver circuit 112 may be formed on the first substrate 11 . For example, an integrated circuit (IC) including a part or all of the functions of the gate-side driver circuit and the source-side driver circuit may be arranged on the first substrate 11 or on the flexible printed circuit substrate 114 . Furthermore, the integrated circuit (IC) 116 of FIG. 1 has the functions of a gate side driver circuit and a part of the source side driver circuit.

Next, the configuration of the display device will be described with reference to FIG. 2 . 2 is a schematic cross-sectional view showing the configuration of a display device according to an embodiment of the present invention.

The display device 1 includes: a first substrate 11, a gate insulating film 15, a thin film transistor 20, a passivation layer 23, a bank layer 25, a reflection layer 27, a wiring layer 29, a color-emitting layer 33, an overcoat layer 34, a first transparent layer Electrode 35, black matrix. The spacer 37 , the first alignment film 39 , the liquid crystal layer 46 , the second alignment film 41 , the second transparent electrode 43 , and the second substrate 45 .

The first substrate 11 and the second substrate 45 are glass substrates. As the material of the first substrate 11 and the second substrate 45, aluminosilicate glass, aluminoborosilicate glass, and the like are used. The second substrate 45 is arranged to face the first substrate 11 . The thin film transistor 20 includes a gate electrode 13 , a source electrode 19 , a drain electrode 21 , and a semiconductor layer 17 . Here, the material of the gate electrode 13 is tantalum (Ta), molybdenum (Mo), molybdenum tantalum (MoTa), molybdenum tungsten (MoW), aluminum (Al), or the like. The material of the semiconductor layer 17 is a-Si (n ⁺ ) doped with impurities (n ⁺ : phosphorus). The material of the source electrode 19 and the drain electrode 21 is, for example, a low-resistance Al-based alloy. A gate insulating film 15 is arranged between the gate electrode 13 and the semiconductor layer 17 . The material of the gate insulating film 15 is, for example, silicon oxide (SiO _x ) or silicon nitride (SiN _x ).

A passivation (protection) layer 23 is disposed on the thin film transistor 20 and the gate insulating film 15 . The material of the passivation layer 23 is, for example, silicon nitride or the like.

The bank layer 25 is disposed on the passivation layer 23 . The bank layer 25 has an opening, and the reflective layer 27 is arranged on the side wall 26 on the side of the opening. The side wall 26 has a tapered shape when viewed in cross section. The bank layer 25 can be formed by forming a coating film of a photosensitive resin composition by exposure, development, and curing. A precise pattern needs to be formed on the bank layer 25 . Therefore, it is preferable that the photosensitive resin composition for forming the bank layer 25 is high in resolution, and the pattern shape after exposure and development is hardly changed in the subsequent heat treatment step. As such a material, a composition containing a resin with high heat resistance is preferable, and examples thereof include a resin containing a cyclic aliphatic group or an aromatic group, and a resin containing a monomer component capable of imparting a high glass transition temperature. Wait. The resin is preferably selected from acrylic resins, siloxane-based resins, polyimide resins, novolak resins, and polyether-based resins. As such a photosensitive resin composition, Japanese Patent No. 3241399, Japanese Patent No. 4207604, Japanese Patent No. 4784283, Japanese Patent No. 4637209, Japanese Patent No. 4637221, Japanese Patent No. 4232527, and Japanese Patent No. 5176768 are applicable. published in Gazette No. Photosensitive resin composition. By using such a material, at the time of hardening of the bank layer 25, the pattern remaining at the time of development can be maintained, and the bank layer 25 having a precise pattern can be obtained.

The reflection layer 27 reflects light incident from the second substrate 45 side. The material of the reflection layer 27 is metal such as aluminum (Al) and silver (Ag). In order to efficiently perform reflection by the reflection layer 27 (increase the light extraction efficiency), the side wall 26 on the side of the opening of the bank layer 25 has a tapered shape in cross-sectional view. The reflection layer 27 has an inclined surface along the side wall 26 of the opening, and a flat surface along the passivation layer 23 exposed on the bottom surface of the opening.

The bank layer 25 has an opening part different from the opening part in which the reflection layer 27 is arranged. The wiring layer 29 is formed in this opening. The first transparent electrode 35 described later is electrically connected to the thin film transistor 20 via the wiring layer 29 . Therefore, the openings different from the openings in which the reflective layer 27 is arranged can be called contact holes.

The color-emitting layer 33 is arranged on the reflective layer 27 . The color-emitting layer 33 is arranged so as to cover the inclined surface and the flat surface of the reflection layer 27 . The detailed configuration and material of the color-developing layer 33 will be described later.

The overcoat layer 34 is arranged on the color-emitting layer 33 , a part of the reflection layer 27 , and a part of the wiring layer 29 . The overcoat layer 34 is arranged for planarization. The material of the overcoat layer 34 is, for example, a strong material such as a transparent epoxy acrylate system. An opening is provided in the overcoat layer 34 so as to expose the wiring layer 29 .

The first transparent electrode 35 is arranged on the overcoat layer 34 , the side wall on the side of the opening of the overcoat layer 34 , and on the wiring layer 29 exposed through the opening of the overcoat layer 34 . The material of the first transparent electrode 35 is, for example, Indium Tin Oxide (ITO) or Indium Zinc Oxide (IZO). The first transparent electrode 35 is a so-called pixel electrode.

black matrix. The spacer (columnar spacer) 37 is arranged on the first transparent electrode 35 having the opening of the overcoat layer 34 . black matrix. The spacer 37 has a function as a black matrix and a function as a spacer for controlling the thickness of the liquid crystal layer 46 . as a black matrix. As the material of the spacer 37, a well-known colored photosensitive resin composition (for example, Japanese Patent Laid-Open No. 2014-146029) can be used.

In the drawing, the second transparent electrode 43 is arranged on the lower side of the second substrate 45 . The material of the second transparent electrode 43 is the same as the material of the first transparent electrode 35 . The second transparent electrode 43 is a so-called common electrode.

The first alignment film 39 is arranged in the black matrix. on the spacer 37 , the first transparent electrode 35 and the overcoat layer 34 . On the other hand, in the drawing, the second alignment film 41 is arranged on the lower side of the second transparent electrode 43 .

The first alignment film 39 and the second alignment film 41 can be formed by using, as a liquid crystal alignment agent, a liquid composition containing a liquid composition selected from the group consisting of polyamic acid, polyimide, and polyamic acid ester At least one polymer (A) in the group consisting of poly(meth)acrylate and polysiloxane is used as a polymer component, and the polymer (A) is dispersed or dissolved in a solvent. From the viewpoint of forming a coating film at a low temperature, the liquid crystal aligning agent preferably contains poly(meth)acrylate or polysiloxane as a polymer component. In addition, in this specification, "poly(meth)acrylate" is set to include polyacrylate and polymethacrylate, and it is preferably obtained by polymerization using a (meth)acrylic monomer. obtained polymer.

The effect of improving the coatability when using a low-boiling point solvent can be sufficiently obtained, and In addition, from the viewpoint of obtaining a liquid crystal element with sufficiently high transparency, the content ratio of the poly(meth)acrylate in the liquid crystal aligning agent is preferably 3% by mass to the total amount of the polymer components of the liquid crystal aligning agent. 99% by mass. The lower limit of the content ratio is more preferably 5% by mass or more, still more preferably 20% by mass, and particularly preferably 50% by mass. In addition, the upper limit is more preferably 95 mass % or less, and still more preferably 90 mass % or less, when the effect of improving various properties by a polymer different from poly(meth)acrylate is obtained. In addition, a poly (meth)acrylate may be used individually by 1 type, and may be used in combination of 2 or more types.

As the polyamic acid used for the liquid crystal aligning agent, one obtained by reacting tetracarboxylic dianhydride and diamine is used. Regarding the usage ratio of tetracarboxylic dianhydride and diamine for the synthesis reaction of polyamic acid, it is preferable that the acid anhydride group of tetracarboxylic dianhydride is 0.2 to 2 equivalents with respect to 1 equivalent of amine group of diamine. The ratio of 0.3 equivalent to 1.2 equivalent is more preferable.

The polyimide used for the liquid crystal aligning agent can be obtained by dehydrating and ring-closing the polyimide synthesized as described above and subjecting it to imidization. The polyimide may be a complete imide compound obtained by dehydrating and ring-closing the entire amide structure of the polyamide acid that is the precursor thereof, or only a part of the amide structure may be dehydrated. A partial amide imide compound in which the ring is closed and the amide acid structure and the amide ring structure coexist. The polyimide used in the liquid crystal alignment agent preferably has an imidization rate of 30% or more, more preferably 40% to 99%, and still more preferably 50% to 99%. The imidization rate is expressed in percentage as the ratio of the number of imide ring structures of the polyimide to the total of the number of imide acid structures and the number of imine ring structures. Here, Aya A part of the amine ring may also be an isoimide ring.

The polyamic acid ester contained in the liquid crystal aligning agent can be obtained, for example, by the following method. (2) A method of reacting a tetracarboxylic acid diester with a diamine; (3) A method of reacting a tetracarboxylic acid diester dihalide and a diamine. Polyamide, polyimide and polyamide preferably have 10mPa when they are made into a solution with a concentration of 10% by weight. s~800mPa. s solution viscosity, more preferably with 15mPa. s~500mPa. s solution viscosity. Furthermore, the solution viscosity (mPa.s) of the polymer is a concentration of 10 wt. % polymer solution, the value measured at 25°C using an E-type rotational viscometer. The reduced viscosity is not particularly limited as long as it is a range in which a uniform coating film can be formed, but is preferably 0.05 dl/g to 3.0 dl/g, more preferably 0.1 dl/g to 2.5 dl/g, and still more preferably 0.3 dl/g g~1.5dl/g.

The polysiloxane can be obtained, for example, by hydrolyzing a hydrolyzable silane compound. The polysiloxane which has functional groups, such as a photoalignment group or a pretilt angle providing group (for example, the vertical alignment group etc. shown below) in a side chain, may be contained in a liquid crystal aligning agent. Such a functional group-containing polysiloxane can be obtained, for example, by synthesizing a polysiloxane having an epoxy group in a side chain by polymerizing at least a part of the raw material using a hydrolyzable silane compound containing an epoxy group. siloxane, and then the polysiloxane with epoxy group and the carboxylic acid with functional group are reacted. Alternatively, the use of a hydrolyzable silane compound having a functional group in the monomer can also be used. Aggregation method.

As a preferable specific example of the organic solvent used for a liquid crystal aligning agent, 2-butanone, 2-hexanone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, butyl acetate, etc. are mentioned. The organic solvent is preferably used in such a manner that the solid content concentration is 5% by mass to 50% by mass. The reaction temperature in the reaction is preferably 0°C to 200°C, and the reaction time is preferably 0.1 hour to 50 hours. After the reaction is completed, the organic solvent layer separated from the reaction liquid is dried with a desiccant if necessary, and then the solvent is removed, whereby a polysiloxane having a functional group can be obtained.

It is preferable that the liquid crystal aligning agent used for formation of the 1st alignment film 39 and the 2nd alignment film 41 contains the polymer which has a photoalignment group. Here, the term "photoalignment group" means imparting each of the films by a photoisomerization reaction or photodimerization reaction by light irradiation, a photolysis reaction, or a photo Fries rearrangement reaction. Anisotropic functional groups. Specific examples of the photoalignment group include, for example, an azobenzene-containing group containing azobenzene or its derivative as a basic skeleton, a cinnamic acid structure-containing group containing cinnamic acid or its derivative as a basic skeleton, Chalcone-containing group containing chalcone or its derivative as the basic skeleton, benzophenone-containing group containing benzophenone or its derivative as the basic skeleton, coumarin or its derivative as the basic skeleton A coumarin-containing group of the skeleton, a polyimide-containing structure including a polyimide or a derivative thereof as a basic skeleton, and the like.

The photoalignment group may be possessed by poly(meth)acrylate, or may be possessed by a polymer different from poly(meth)acrylate. As the main skeleton of the polymer, for example, polyamic acid, polyamic acid ester, polyimide, polysiloxane, Polyamide, etc. From the viewpoint of securing the reliability and weather resistance of the liquid crystal element, polysiloxane having a photoalignment group can be preferably used.

When the liquid crystal aligning agent contains a polymer having a photoalignment group and a polymer not having a photoalignment group, from the viewpoint of imparting sufficient alignment ability to the coating film formed using the liquid crystal aligning agent by irradiation with radiation. In other words, the content ratio of the polymer having a photoalignment group is preferably 1 mass % or more with respect to the total amount of the polymer components in the liquid crystal aligning agent, and more preferably 5 mass % to 99 mass %.

The polymer component contained in the liquid crystal aligning agent is not limited to the above-mentioned poly(meth)acrylate and polysiloxane, and may also contain other polymers. Examples of other polymers include polyamides, polyimides, polyamides, polyamides, polyesters, cellulose derivatives, polyacetals, polystyrene derivatives, poly(benzene) Ethylene-phenylmaleimide) derivatives, etc. Among these other polymers, preferably at least one selected from the group consisting of polyamic acid and polyamic acid ester, more preferably polyamic acid.

The blending ratio of the other polymer is preferably 20 mass % or less, more preferably 10 mass % or less, and further preferably 5 mass % with respect to the total amount of the polymer components in the liquid crystal aligning agent. the following. Furthermore, other polymers may be used alone or in combination of two or more.

The liquid crystal aligning agent preferably contains a compound having a crosslinkable group (hereinafter, also referred to as a crosslinking agent) as another component. The crosslinkable group is a group that can form a covalent bond between the same or different molecules by light or heat, for example, a (meth)acryloyl group, a group having a vinyl group (alkenyl group, vinylphenyl group) etc.), ethynyl, epoxy (oxetanyl, oxetanyl), carboxyl, (protected) isocyanate groups, and the like. Of these, From the viewpoint of high reactivity, a (meth)acryloyl group is particularly preferred. In addition, a "(meth)acryloyl group" means an acryl group and a methacryloyl group. The number of the crosslinkable group which the crosslinking agent has may be one or plural. From the viewpoint of sufficiently improving the reliability of the liquid crystal element, it is preferably two or more, and more preferably two to six.

As other components contained in a liquid crystal aligning agent, an antioxidant, a metal chelate compound, a hardening accelerator, a surfactant, a filler, a dispersing agent, a photosensitizer etc. are mentioned, for example. The compounding ratio of these other components can be suitably selected according to each compound.

With regard to the organic solvent used in the preparation of the liquid crystal aligning agent, from the viewpoint of forming a coating film at a low temperature, it is preferable to contain 40% by mass or more of a compound having a boiling point of 160° C. or lower with respect to the total amount of the solvent, and more preferably It is preferable to contain 50 mass % or more, and it is more preferable to contain 70 mass % or more.

The solid content concentration in the liquid crystal aligning agent (the ratio of the total mass of the components other than the solvent of the liquid crystal aligning agent to the total mass of the liquid crystal aligning agent) is appropriately selected in consideration of viscosity, volatility, etc., and is preferably 1 mass % to 10% by mass. When the solid content concentration is less than 1 mass %, the film thickness of the coating film is too small, and it is difficult to obtain a good liquid crystal alignment film. On the other hand, when the solid content concentration exceeds 10 mass %, the film thickness of the coating film is too large, making it difficult to obtain a good liquid crystal alignment film, and the viscosity of the liquid crystal aligning agent tends to increase and the applicability tends to decrease.

Use a bar coater to coat the prepared liquid crystal alignment agent on the first transparent electrode 35, the overcoat layer 34 and the black matrix. On the spacer 37, after pre-baking with a hot plate at 80° C. for 1 minute, heating (post-baking) for 2 minutes in an oven at 120° C. in which the inside of the chamber was replaced with nitrogen gas can form an average film thickness. 0.1μm coating film. Then, the surface of the produced coating film was irradiated with 20 mJ/cm ² of polarized ultraviolet rays including a bright line of 313 nm from a direction inclined by 20° from the substrate normal using a Hg-Xe lamp and a Glan Taylor lamp. Thus, the first alignment film 39 can be formed. The second alignment film 41 can also be produced in the same manner.

The liquid crystal layer 46 is arranged between the first transparent electrode 35 and the second transparent electrode 43 . The liquid crystal layer 46 is arranged between the first alignment film 39 and the second alignment film 41 . The liquid crystal layer 46 has a dimming function. As will be described later, in this embodiment, each color-developing layer contains quantum dots. In addition, the quantum dot does not retain the polarization state with respect to the emission of excitation light. In other words, even when polarized light is incident on the quantum dot, the light emission is non-polarized light. Therefore, the liquid crystal layer 46 with a dimming function is preferably a liquid crystal layer that does not require a polarizer. Specifically, the liquid crystal layer 46 is a guest-host liquid crystal layer of a chiral nematic type (positive liquid crystal). Since it is a guest-host liquid crystal layer, the liquid crystal layer 46 includes liquid crystal molecules 47 and a dichroic dye 49 . As the dichroic dye 49, dichroic dyes such as azo-based, anthraquinone-based, naphthoquinone-based, perylene-based, and dioxazine-based dyes can be used. Specific examples of such dichroic dyes include U.S. Patent No. 4,154,746, Japanese Patent Laid-Open No. 10-183122, Japanese Patent Laid-Open No. 2018-003020, and Japanese Patent Laid-Open No. 2018-053167 The described dichroic dye.

[Constitution of the color-forming layer]

Here, the structure of the color-emitting layer 33 shown in FIG. 2 is common to all of the blue-emitting blue color-emitting layer, the red-emitting red color-emitting layer, and the green-emitting green color-emitting layer. Therefore, in the drawing, only sub-pixels of any color are shown. Furthermore, with red (R), A group of three colors, green (G) and blue (B), is one pixel. However, in each color-developing layer, as described below, the substances constituting the color-developing layer are different.

In this example, the blue color-emitting layer includes blue QDs (Quantum Dot; quantum dots), scattering particles, green absorbers, and red absorbers. As the blue QDs, for example, blue QDs manufactured by SIGMA-ALDRICH (product number: 753742, product name: CdSeS/ZnS alloy quantum dots) can be used. In addition, as the scattering particles, spherical alumina (product names: DAM-03, DAM-07) manufactured by Denka Co., Ltd., and silicon dioxide particles (product name) manufactured by Nippon Shokubai Co., Ltd. can be used. : KE-P250, MM-P), zirconia particles (product name: TZ-3YS-E) manufactured by Tosoh Co., Ltd., titanium dioxide particles (product name: R-) manufactured by Sakai Chemical Industry Co., Ltd. 38L) etc. As the green absorber, a visible light absorber (product name: FDG-02, absorption wavelength: 525 nm) manufactured by Yamada Chemical Co., Ltd. or phycoerythrin as a pigment protein can be used. As the red absorbent, phycocyanin, which is a pigment protein, can be used.

In this example, the green color-emitting layer includes green QDs, scattering particles, and red absorbers. As green QDs, for example, green QDs (product name: CZ520-100) manufactured by NN-Labs, and QDs (product name: GREEN-CFQD-) manufactured by NANOCO TECHNOLOGIES can be used G3-525), green QD (product number: 753831, product name: CdSeS/ZnS alloy quantum dots) manufactured by SIGMA-ALDRICH, manufactured by SIGMA-ALDRICH The green QD (Article No.: 776750, product name: InP/ZnS quantum dots) and the like. As the scattering particles, the same scattering particles that can be used in the blue color-emitting layer can be used.

The red chromophoric layer includes red QDs and scattering particles. As red QDs, red QDs (product name: CZ620-100) manufactured by NN-Labs, and QDs (product name: RED-CFQD-G2-) manufactured by NANOCO TECHNOLOGIES 604), red QD manufactured by SIGMA-ALDRICH (product number: 753882, product name: CdSeS/ZnS alloy quantum dots (alloyed quantum dots)), red manufactured by SIGMA-ALDRICH QD (product number: 776777, product name: InP/ZnS quantum dots) and the like. As the scattering particles, the same scattering particles that can be used in the blue color-emitting layer can be used. In addition, as other QDs, ZnSeTe-based QDs (" Mater. Res. Express " (4(2017) 106501)) and AgInS ₂ -based QDs (Japanese Patent No. 6293710) can be used.

The color of the incident light L _i incident from the second substrate 45 side and the color of the outgoing light L _o emitted from the second substrate 45 side are different from each other. In other words, the wavelength components included in the incident light L _i incident from the second substrate 45 side and the wavelength components included in the outgoing light L _o emitted from the second substrate 45 side are different from each other. In this example, the color of the incident light _Li is white. On the other hand, the color of the outgoing light L _o is blue when emitted from the second substrate 45 side through the blue color-emitting layer, and is blue when emitted from the second substrate 45 side through the green color-emitting layer , is green, and is red when it is emitted from the second substrate 45 side through the red color-emitting layer.

In the present embodiment, the half-value width of the spectrum is narrowed compared with the prior art, so that the color purity is high. Therefore, in the present embodiment, a display device with better display quality can be provided.

In this embodiment, scattering particles are contained in each color-developing layer. Therefore, the viewing angle dependence of color can be reduced. In addition, the light emission from each QD is omnidirectional. Therefore, if there are no scattering particles, there is also light that is totally reflected and enclosed in the display device, but this can be prevented by the presence of the scattering particles. In addition, in the present embodiment, the liquid crystal layer 46 is a guest-host liquid crystal layer of a chiral nematic type (positive type liquid crystal). Therefore, the dimming function can be realized without a polarizer.

In this embodiment, the display device 1 includes the thin film transistor 20 in addition to the reflective layer 27 . Therefore, it can be applied to electronic paper such as electronic books and electronic textbooks, and digital signage for outdoor use.

[Manufacturing method of display device]

Next, a method of manufacturing a display device according to an embodiment of the present invention will be described with reference to FIGS. 3 to 10 . 3 to 10 are schematic cross-sectional views for explaining a step of a method for manufacturing a display device according to an embodiment of the present invention, respectively.

First, after cleaning the mother glass substrate (first substrate) 11, a metal film is deposited on the entire first substrate 11 by sputtering. Next, the gate electrode 13 and the storage capacitor electrode (not shown) as shown in FIG. 3 are patterned using a lithography technique. Next, as shown in FIG. 4 , the gate insulating film 15 is formed on the entire surface of the first substrate 11 by chemical vapor deposition (CVD) method. Further, the semiconductor layer 17 is deposited to form a metal film such as Al. Also, using lithography The technique patterns the desired areas to form the source electrode 19 and the drain electrode 21 . Next, the passivation layer 23 is formed on the entire surface of the first substrate 11 , that is, on the gate insulating film 15 , the source electrode 19 and the drain electrode 21 , and the semiconductor layer 17 using CVD.

Next, the photosensitive resin composition is subjected to coating film formation using a wet film formation method, followed by exposure through a photomask. Hereinafter, the photosensitive resin composition will be described as being positive. As a photomask, it is preferable to use a multi-tone mask called a so-called halftone mask or a gray-tone mask. The bank layer is formed by removing the exposed portion by development and curing the coating film remaining in the unexposed portion. It is preferable to carry out in the range of 120 degreeC - 250 degreeC of hardening temperature. Openings are formed in desired regions of the bank layer so as to expose the passivation layer 23, and the bank layer 25 is formed. Furthermore, in order to expose a part of the drain electrode 21, the passivation layer 23 of the required area|region is etched, and a contact hole is formed. Next, a metal film of silver or aluminum is formed on the entire surface of the first substrate 11, that is, the bank layer 25 (including the sidewalls 26), the passivation layer 23, and the drain electrode 21, and the unnecessary parts are selectively etched, Thereby, the reflection layer 27 and the wiring layer 29 are formed (FIG. 5).

Next, as shown in FIG. 6 , the color-emitting layer 33 is formed on the reflection layer 27 and on the opening of the bank layer 25 . In addition, the color-developing layer 33 includes a blue color-developing layer, a red color-developing layer, and a green color-developing layer. Each chromonic layer contains each QD. Moreover, the preparation of the composition of each QD is as follows. That is, first, the following polymers were synthesized. Specifically, 150 parts by mass of propylene glycol monomethyl ether acetate was put into a flask provided with a cooling pipe and a stirrer, and nitrogen substitution was performed. Then, it was heated to 80° C., and 50 parts by mass of propylene glycol monomethyl ether acetate and 2-methacryloyloxyethyl succinic acid were added dropwise at the same temperature over 2 hours. 30 parts by mass of ester, 10 parts by mass of benzyl methacrylate, 60 parts by mass of 2-ethylhexyl methacrylate, and 6 parts by mass of 2,2'-azobis(2,4-dimethylvaleronitrile) The mixed solution was kept at this temperature and the polymerization was carried out for 1 hour. Then, the temperature of the reaction solution was raised to 90° C., and the polymerization was further performed for 1 hour to obtain a polymer. The polymer was obtained in the state of a polymer solution (solid content concentration=33 mass %).

After adding and dissolving 40 parts by mass of methylcyclohexane to 90 parts by mass of the polymer solution, 10 parts by mass of QD was mixed to prepare a uniform solution. For example, in the case of the blue color-developing layer, after adding 40 parts by mass of methylcyclohexane to 90 parts by mass of the polymer solution and dissolving it, 10 parts by mass of blue QDs are mixed to prepare a uniform solution , and then mixed in the order of scattering particles, red absorber, and green absorber. This mixed solution was mixed with 1,2-octanedione-1-[4-(phenylthio)-2-(O-benzyl oxime)] (Irangarco (Irrigacur) (manufactured by BASF Japan). Irgacure) (registered trademark) OXE01) 10 parts by mass and 70 parts by mass of 1,9-nonanediol diacrylate to prepare a QD-containing composition. The prepared composition containing each QD is applied on the reflective layer 27 and on the opening of the bank layer 25 , thereby forming the color-emitting layer 33 .

Next, as shown in FIG. 7 , the overcoat layer 34 is formed on the entire surface of the first substrate 11 , and a part of the overcoat layer 34 is etched so as to expose a part of the wiring layer 29 . Next, as shown in FIG. 8 , the first transparent electrode 35 is formed on a part of the overcoat layer 34 and a part of the wiring layer 29 . The formation method of the 1st transparent electrode 35 is any of a well-known DC sputtering method, a high frequency sputtering method, a plasma ion plating method, and the like. Then, using a known method (for example, Japanese Patent Laid-Open No. 2014-146029) method to form a black matrix. Spacer 37.

Next, as shown in FIG. 9, on the entire surface of the first substrate 11, that is, a part of the overcoat layer 34, a part of the first transparent electrode 35 and the black matrix. The first alignment film 39 is formed on the spacer 37 . Specifically, the first alignment film 39 is formed by applying the material for forming the first alignment film 39 to the first substrate 11 and firing to obtain a desired film thickness. Furthermore, in this example, the first alignment film 39 is a horizontal alignment film. In addition, in consideration of the heat resistance of the quantum dots contained in the color-emitting layer 33, the firing temperature of the first alignment film 39 is preferably low. The calcination temperature is desirably 180°C or lower, and more desirably 160°C or lower. More preferably, the firing temperature of the first alignment film 39 is 140° C. or lower.

After the first alignment film 39 is formed, a rubbing treatment is performed in order to align the liquid crystal molecules 47 and the dichroic dye 49 in a certain direction. In addition, it is desirable that the rubbing direction is an orientation in which the alignment twist of the liquid crystal molecules 47 and the dichroic chromaticity 49 is about 180° to 360°.

Then, as shown in FIG. 10, the separately manufactured opposing substrate (the second transparent electrode 43 and the second alignment film 41 are sequentially laminated on the second substrate 45) is arranged on the side of the first substrate 11, that is, the black matrix. on spacer 37. Specifically, a liquid crystal material obtained by adding an appropriate amount of dichroic dye 49 and a chiral material that induces spontaneous twisting to liquid crystal (positive liquid crystal) having positive dielectric anisotropy is prepared in advance. Then, a predetermined amount of the liquid crystal material is dropped into the display area (area) of the first substrate 11 using a dispenser. The sealant is drawn outside the display area of the opposite substrate. In addition, from the viewpoint of adhesive strength, it is desirable to perform tracing on a portion where there is no second alignment film 41 . painting. Here, the sealant may be drawn on the portion outside the display area where the second alignment film 41 exists to narrow the frame width of the display device. Then, the two substrates, the first substrate 11 and the opposing substrate, are bonded together after the chamber is evacuated and aligned. Next, the sealing portion is irradiated with ultraviolet rays and hardened. Furthermore, it heated to 130 degreeC in an oven at normal pressure, and fully hardened the sealant.

<Variation 1>

The above embodiments have been described on the premise that the blue color-emitting layer includes blue QDs, scattering particles, green absorbers, and red absorbers, and the green color-emitting layer includes green QDs, scattering particles, and red absorbers. The red chromophore layer contains red QDs and scattering particles. However, each color-developing layer is not limited to this. Different from the above embodiments, for example, the blue color-emitting layer may not include blue QDs but may include scattering particles, green absorbers, and red absorbers. The green chromophoric layer may also contain green QDs and red absorbers without scattering particles. The red chromophoric layer may also include red QDs without scattering particles.

In addition, each color-developing layer of 1st Embodiment may be combined with each color-developing layer in this modification. For example, the blue color-emitting layer may include blue QDs, scattering particles, green absorbers, and red absorbers as in the first embodiment, while the green color-emitting layer may not include scattering particles as in this modification. On the other hand, including the green QD and the red absorber, the red color-emitting layer does not include scattering particles but includes the red QD as in the present modification. The combination of each color-developing layer can be appropriately changed.

<Second Embodiment>

A display device according to another embodiment of the present invention will be described with reference to FIG. 11 . Bright. The display device of the present embodiment is substantially the same as the display device of the first embodiment. Therefore, the different points will be described in detail, and the description of the overlapping portions will be omitted.

Unlike the display device of the first embodiment, the display device of the second embodiment has a scattering layer 31 . In this example, as shown in FIG. 11 , the scattering layer 31 is arranged between the reflection layer 27 and the color-emitting layer 33 . The scattering layer 31 has a function of scattering light incident on the scattering layer 31 .

In addition, also in this embodiment, the color-developing layer 33 is different from the color-developing layer 33 of the first embodiment. Specifically, in this embodiment, the blue color-emitting layer contains blue QDs, but does not contain green absorbers and red absorbers. Similarly, the green color-emitting layer of the present embodiment contains green QDs, but does not contain a red absorber. Instead, the scattering layer 31 arranged below the blue color-emitting layer of the present embodiment contains a green absorber and a red absorber. In addition, the scattering layer 31 arranged on the lower side of the green color-emitting layer in the present embodiment contains a red absorber. That is, in the present embodiment, in the color-developing layer 33 in the first embodiment, when the concentration of scattering particles or the concentration of the absorber becomes too high in a single layer, these are separated and provided separately. layer (scattering layer 31). This embodiment also exhibits the same effects as those of the first embodiment.

<Variation 2>

The above second embodiment has been described on the premise that the blue color-developing layer contains blue QDs without scattering particles, the green color-developing layer contains green QDs without scattering particles, and the red color-developing layer contains green QDs. No scattering particles but red QDs are included. However, each color-developing layer is not limited to this. Scattering particles may be included in each chromonic layer. In addition, the concentration of scattering particles in this case is such that each color-emitting layer may be in the form of a single layer. Consists of a range of concentrations. This modification also exhibits the same effects as those of the second embodiment. Furthermore, in the present modification, by further including scattering particles in each color-developing layer, the light is further scattered and the visual dependence of the color can be further reduced as compared with the second embodiment.

<The third embodiment>

Unlike the display device of the first embodiment, the display device of the third embodiment has a scattering layer 31 . In this example, as in the second embodiment (see FIG. 11 ), the scattering layer 31 is arranged between the reflective layer 27 and the color-emitting layer 33 . The scattering layer 31 has a function of scattering light incident on the scattering layer 31 .

In addition, also in this embodiment, the color-developing layer 33 is different from the color-developing layer 33 of the first embodiment. Specifically, in the present embodiment, the color-developing layer of each color contains QDs of each color, but does not contain a color absorber. In addition, the scattering layer 31 arranged on the lower side of the color-developing layer of the present embodiment contains a color absorber that absorbs light other than the color emitted by the color-developing layer. Specifically, the scattering layer 31 arranged on the lower side of the blue color-emitting layer of the present embodiment contains a green absorber and a red absorber. The scattering layer 31 disposed below the green color-emitting layer contains a blue absorber and a red absorber. The scattering layer 31 disposed below the red color-emitting layer contains a blue absorber and a green absorber. In addition, as a red absorber and a green absorber, the compound demonstrated in the description of 1st Embodiment is used suitably. Furthermore, as the blue absorber, those selected from C.I. Pigment Yellow 150, C.I. Pigment Yellow 213, C.I. Pigment Yellow 215, C.I. Pigment Yellow 185, C.I. Pigment Yellow 138, C.I. Pigment Yellow 139, C.I. Solvent Yellow) 21, C.I. Solvent Yellow 82, C.I. Solvent Yellow 83:1, C.I. Solvent Yellow 33, C.I. Solvent Yellow 162 At least one yellow organic dye pigment in the group consisting of. That is, regarding this implementation In the color-emitting layer 33 in the first embodiment, blue light and green light that are not absorbed by the QDs of the respective colors are absorbed by the lower scattering layer 31, whereby the following effect can be achieved: preventing these lights from being emitted from the pixels again , and prevent the color purity of each pixel from degrading. At the same time, in the color-forming layer 33 in the first embodiment, when the concentration of scattering particles or the concentration of the absorber becomes too high in a single layer, these are separated to provide another layer ( scattering layer 31), the present embodiment also exhibits the same effects as those of the first embodiment.

<Variation 3>

The above-mentioned third embodiment has been described on the premise that the blue color-developing layer contains blue QDs without scattering particles, the green color-developing layer contains green QDs without scattering particles, and the red color-developing layer contains green QDs. No scattering particles but red QDs are included. However, each color-developing layer is not limited to this. Scattering particles may be included in each chromonic layer. In addition, the density|concentration of the scattering particle|grains in this case is the density|concentration in the range which each color-developing layer can be comprised as a single layer. This modification also exhibits the same effects as those of the third embodiment. Furthermore, in the present modification, by further including scattering particles in each color-developing layer, the light is further scattered and the visual dependence of the color can be further reduced as compared with the third embodiment.

<Variation 4>

In the above-described embodiment and modification examples, the color-emitting layer 33 is formed by applying the prepared composition containing each QD on the reflective layer 27 and the opening of the bank layer 25 . However, the method of forming the color-developing layer 33 is not limited to this. For example, the color-developing layer 33 can also be formed by coating with ink jet. As the inkjet composition, known ones (for example, Japanese Patent Laid-Open No. 2010-9995, The QD composition of Japanese Patent Laid-Open No. 2009-76282, etc.). This modification also exhibits the same effects as those of the above embodiment.

<Variation 5>

In the above-mentioned embodiment and modification, the description has been made on the premise that the guest-host liquid crystal layer 46 is a liquid crystal layer of a chiral nematic type (positive liquid crystal). However, the guest-host liquid crystal layer 46 is not limited to this. It can also be a chiral nematic type (negative liquid crystal), a phase-transition guest-host mode, a polymer-dispersed type, and a polymer-stabilized cholesteric blue phase, which are described in detail below. In addition, in the following description, only the point which differs from the guest-host type liquid crystal layer 46 using the chiral nematic type (positive type liquid crystal) will be described in detail, and the detailed description of overlapping parts will be omitted.

[Chiral Nematic Type (Negative Liquid Crystal)]

In the case of a chiral nematic type (negative type liquid crystal), the prepared liquid crystal is a liquid crystal (negative type liquid crystal) having negative dielectric anisotropy. For example, MLC-6609 manufactured by Merck, Inc. can be used. In addition, the used alignment film is a vertical alignment film. This modification also exhibits the same effects as those of the above embodiment. In addition, the chiral nematic type (negative liquid crystal) displays white when the voltage is off, and displays black (normally white) when the voltage is on. In the use of electronic books or electronic labels, the area displayed in white is often dominant, so power consumption can be further reduced, which is advantageous from the viewpoint of burn-in and reliability.

[Phase change guest-host mode]

Compared with the case of the chiral nematic type (positive liquid crystal), the addition amount of the chiral material is increased. Specifically, the addition amount of the chiral material is set to 10% or more to stimulate the bile steroid layer. This modification also exhibits the same effects as those of the above embodiment. In addition, in the case of this modification, a stable alignment state of planar (planer), focal conic (focal conic), and homeotropic (homeotropic) can exist according to the driving waveform, and therefore has display retention characteristics (memory). Therefore, display using simple matrix or segment driving can be performed without using an active matrix. In addition, the memory property is suitable for use in electronic books or electronic tags that place importance on power consumption.

[Polymer dispersion type]

In the case of polymer dispersed liquid crystal (PDLC), compared with the case of chiral nematic type (positive liquid crystal), the addition amount of chiral material is increased, and the polymerizable monomer is also added. After the liquid crystal is enclosed, ultraviolet irradiation is performed. For example, 90wt% of "BL007" (trade name) manufactured by Merck Co., Ltd. as a liquid crystal, and 3wt% of "CB15" manufactured by Merck Co., Ltd. as a chiral component are prepared. (trade name) and 7 wt % of biphenyl methacrylate as a polymer precursor mixed with a solution, the solution was injected into an empty cell with a gap (gap) between the substrates of about 5 μm, and after sealing , irradiating ultraviolet rays to phase-separate the polymer particles in the liquid crystal. This modification also exhibits the same effects as those of the above embodiment. In addition, since there is almost no dependence on the alignment orientation, there is no yield reduction due to poor alignment during manufacturing.

[Polymer Stabilized Cholesterol Blue Phase]

In this case, compared with the case of a chiral nematic type (positive liquid crystal), the addition amount of the chiral material is increased, and a polymerizable monomer is also added, and after the liquid crystal is enclosed, ultraviolet irradiation is performed. Among them, ultraviolet irradiation is in the temperature range of cholesterol blue phase implement. For example, "JC-1014XX" (trade name, nematic liquid crystal mixture manufactured by Chisso Co., Ltd.), 4-cyano- 4'-pentylbiphenyl (manufactured by SIGMA-ALDRICH) and chiral dopant ("ZLI-4572" (trade name) manufactured by Merck) mixture. This mixture, TMPTA (trimethylolpropane triacrylate, manufactured by SIGMA-ALDRICH), Mix RM257 and DMPA (2,2-dimethoxy-2-phenyl-acetophenone), and keep it in the vicinity of cholesterol-cholesterol blue phase transition temperature. Cholesterol blue phase, while irradiating ultraviolet rays, polymerizes photoreactive monomers. This modification also exhibits the same effects as those of the above embodiment. In addition, since there is almost no dependence on the alignment orientation, there is no yield reduction due to poor alignment during manufacturing.

<Variation 6>

The first embodiment to the third embodiment and the modifications thereof have been described on the premise that a transistor layer exists, that is, an active matrix driving method. However, the driving method is not limited to this, and can be appropriately changed according to the purpose. For example, in order to provide an inexpensive display device, a known simple matrix method can also be used. In addition, a well-known segment drive method can also be used. In this way, the electronic label previously displayed in monochrome can be turned into a high-quality color electronic label. Furthermore, in the above-mentioned embodiment and modification, the transistor was demonstrated on the premise that the transistor is a so-called reverse staggered type. However, it is not limited Here, the staggered type may also be used. According to this modification, the same effects as those of the first embodiment are exhibited.

In addition, this invention is not limited to the said embodiment, It can change suitably in the range which does not deviate from the summary.

<4th Embodiment>

12 is a schematic cross-sectional view showing the configuration of the display device according to the embodiment of the present invention in a first state. Here, the first state refers to a state in which no voltage is applied between the first transparent electrode 35 and the second transparent electrode 43 .

The display device 1 includes: a first substrate 11, a gate insulating film 15, a thin film transistor 20, a passivation layer 23, a bank layer 25, a reflection layer 27, a wiring layer 29, a color-emitting layer 33, an overcoat layer 34, a first transparent layer The electrode 35 , the second transparent electrode 43 , and the second substrate 45 . The configurations of these members are the same as those in the first embodiment. The display device of the present embodiment includes a layer 40 having a light-adjusting function (hereinafter, sometimes referred to as "light-adjusting layer 40") in place of the liquid crystal layer and the alignment film of the first embodiment.

The light-adjusting layer 40 is arranged between the first transparent electrode 35 and the second transparent electrode 43 . The light-adjusting layer 40 includes a hydrophobic film 51 , a first partition wall material 53 , a second partition wall material 55 , a first liquid 57 and a second fluid 59 . The light-adjusting layer 40 includes particles or liquids having chargeability. As an example of using particles having chargeability, there is an electrophoretic method. On the other hand, as a method using a liquid, there is an electrowetting method. As an electrophoresis type system, particles disclosed in Japanese Patent No. 5904994 can be used. Furthermore, from the viewpoint of high contrast and high responsiveness, the electrowetting method is preferred. In the following description, the electrowetting method is used as an example for description.

The hydrophobic film 51 is arranged on the first transparent electrode 35 . The surface of the hydrophobic film 51 is in contact with at least the first liquid 57 . In this example, the hydrophobic film 51 contains an amorphous fluoropolymer.

The first partition material 53 and the second partition material 55 define the upper part of the hydrophobic film 51 . That is, the space between the hydrophobic film 51 and the second transparent electrode 43 is partitioned by the first partition material 53 and the second partition material 55 . The second partition wall material 55 is arranged on the first partition wall material 53 . The first partition wall material 53 has high wettability (hydrophobicity) with respect to the first liquid 57 . On the other hand, the second partition wall material 55 has low wettability (hydrophilicity) with respect to the first liquid 57 . In this example, the total thickness of the first partition wall material 53 and the second partition wall material 55 is preferably about 20 μm or less.

The first liquid 57 is a non-polar solvent, in this example, black oil. The second fluid 59 is polar, and in this example, pure water. The first liquid 57 and the second fluid 59 are arranged between the hydrophobic film 51 and the second transparent electrode 43 in a region defined by the first partition material 53 and the second partition material 55 .

When no voltage is applied, the hydrophobic film 51 is in a state mainly in contact with the first liquid 57 as shown in FIG. 12 . On the other hand, when a voltage is applied, the first liquid 57 moves on the surface of the hydrophobic film 51 and, as shown in FIG. 13 , the region where the first liquid 57 does not exist is in contact with the second fluid 59 . Here, FIG. 13 is a schematic cross-sectional view showing the configuration of the display device according to the embodiment of the present invention in a second state. The second state refers to a state in which the second voltage is applied between the first transparent electrode 35 and the second transparent electrode 43 . The second voltage refers to a voltage in which charges are generated on the surface of the hydrophobic film 51 by applying the second voltage, and When the charge is applied, the second fluid 59 pushes away the first liquid 57 in contact with the hydrophobic film 51 and comes into contact with the hydrophobic film 51, so that the state shown in FIG. 13 can be achieved. At this time, the first liquid 57 continues to move due to the presence of the second partition wall material 55 having low wettability. In this way, regarding the first liquid 57 and the second fluid 59 , the region defined by the first partition material 53 and the second partition material 55 between the hydrophobic film 51 and the second transparent electrode 43 is formed by the first liquid 57 function as a display unit for displaying images. That is, the state in which the voltage is not applied between the first transparent electrode 35 and the second transparent electrode ( FIG. 12 ) and the state in which the second voltage is applied between the first transparent electrode 35 and the second transparent electrode ( FIG. 13 ) The change is recognized by the observer as the "off" or "on" state of the pixel. In addition, the area of the contact between the second fluid 59 and the hydrophobic film 51 depends on the magnitude of the voltage applied between the first transparent electrode 35 and the second transparent electrode. Therefore, various gray scales can be displayed in the pixels according to the voltage. The above method is referred to as a so-called electrowetting method.

[Manufacturing method of display device]

The gate electrode 13 , the gate insulating film 15 , the semiconductor layer 17 , the source electrode 19 , the drain electrode 21 , the passivation layer 23 , and the bank are formed on the mother glass substrate (first substrate) 11 as in the first embodiment. layer 25, reflective layer 27, wiring layer 29, color-emitting layer 33 (refer to FIGS. 3 to 6).

Then, as shown in FIG. 14 , the overcoat layer 34 is formed on the entire surface of the first substrate 11 , and a part of the overcoat layer 34 is etched so as to expose a part of the wiring layer 29 . Next, as shown in FIG. 14 , the first transparent electrode 35 is formed on a part of the overcoat layer 34 and a part of the wiring layer 29 . The method of forming the first transparent electrode 35 is as follows: Any of the known DC sputtering method, high frequency sputtering method, plasma ion plating method and the like. Next, the hydrophobic film 51 is formed on the first transparent electrode 35 by a known coating method or transfer method.

Next, as shown in FIG. 15 , the first partition wall material 53 is formed by a known printing process such as lithography. Then, as shown in FIG. 15 , a predetermined amount of the first liquid 57 is dripped with a dispenser in an area (ie, a display area) partitioned by the hydrophobic film 51 and the first partition wall material 53 .

Next, as shown in FIG. 16 , a separately manufactured opposing substrate (which is obtained by laminating the second transparent electrode 43 and the second partition material 55 on the second substrate 45 in this order) is prepared. And the sealant is drawn outside the display area of the opposing substrate. Then, the two substrates, the first substrate 11 and the opposing substrate, are bonded together after the chamber is evacuated and aligned. Further, the sealing portion is irradiated with ultraviolet rays to be cured. Next, it heated to 130 degreeC in an oven at normal pressure, and fully hardened the sealant. Next, the bonded substrate and the second fluid 59 are placed in the chamber, and the chamber is evacuated, and then the injection port of the bonded substrate is brought into contact with the second fluid 59 to return to atmospheric pressure, whereby the injection port is The second fluid 59 is injected into the display area. After the second fluid 59 is injected, the injection port is blocked with an ultraviolet curable adhesive (sealing material).

<Variation 7>

The fourth embodiment has been described on the premise that the blue color-emitting layer contains blue QDs, scattering particles, a green absorber, and a red absorber, and the green color-emitting layer contains green QDs, scattering particles, and red absorbers. The red chromophore layer contains red QDs and scattering particles. However, each color-developing layer is not limited to this. with the fourth embodiment Differently, for example, the blue color-emitting layer may not include blue QDs but include scattering particles, green absorbers, and red absorbers. The green chromophoric layer may also contain green QDs and red absorbers without scattering particles. The red chromophoric layer may also include red QDs without scattering particles.

In addition, each color-developing layer of 4th Embodiment may be combined with each color-developing layer in this modification. For example, the blue color-emitting layer may include blue QDs, scattering particles, green absorbers, and red absorbers as in the fourth embodiment, while the green color-emitting layer may not include scattering particles as in this modification. On the other hand, including the green QD and the red absorber, the red color-emitting layer does not include scattering particles but includes the red QD as in the present modification. The combination of each color-developing layer can be appropriately changed.

<Fifth Embodiment>

A display device according to the fifth embodiment will be described with reference to FIG. 17 . The display device of the present embodiment is substantially the same as the display device of the fourth embodiment. Therefore, the different points will be described in detail, and the description of the overlapping portions will be omitted.

Unlike the display device of the fourth embodiment, the display device of the fifth embodiment has a scattering layer 31 . In this example, as shown in FIG. 17 , the scattering layer 31 is arranged between the reflection layer 27 and the color-emitting layer 33 . The scattering layer 31 has a function of scattering light incident on the scattering layer 31 .

In addition, also in this embodiment, the color-developing layer 33 is different from the color-developing layer 33 of the fourth embodiment. Specifically, in this embodiment, the blue color-emitting layer contains blue QDs, but does not contain green absorbers and red absorbers. Similarly, the green color-emitting layer of the present embodiment contains green QDs, but does not contain a red absorber. In its place, this implementation Morphology The scattering layer 31 disposed below the blue color-emitting layer contains a green absorber and a red absorber. In addition, the scattering layer 31 arranged on the lower side of the green color-emitting layer in the present embodiment contains a red absorber. That is, in the present embodiment, in the color-developing layer 33 in the fourth embodiment, when the concentration of scattering particles or the concentration of the absorber becomes too high in a single layer, these are separated and provided separately. layer (scattering layer 31). This embodiment also exhibits the same effects as those of the fourth embodiment.

<Variation 8>

In the above fifth embodiment, the description has been made on the premise that the blue color-developing layer contains blue QDs without scattering particles, the green color-developing layer contains green QDs without scattering particles, and the red color-developing layer contains green QDs. No scattering particles but red QDs are included. However, each color-developing layer is not limited to this. Scattering particles may be included in each chromonic layer. In addition, the density|concentration of the scattering particle|grains in this case is the density|concentration in the range which each color-developing layer can be comprised as a single layer. This modification also exhibits the same effects as those of the fifth embodiment. Furthermore, in the present modification, by further including scattering particles in each color-developing layer, the light is further scattered and the visual dependence of the color can be further reduced as compared with the fifth embodiment.

<Sixth Embodiment>

Unlike the display device of the fourth embodiment, the display device of the sixth embodiment has a scattering layer 31 . In this example, as in the fifth embodiment (see FIG. 17 ), the scattering layer 31 is arranged between the reflective layer 27 and the color-emitting layer 33 . The scattering layer 31 has a function of scattering light incident on the scattering layer 31 .

In addition, also in this embodiment, the color-developing layer 33 is different from the color-developing layer 33 of the fourth embodiment. Specifically, in this embodiment, the color-developing layers of each color include each color QD, but does not contain color absorbers. In addition, the scattering layer 31 arranged on the lower side of the color-developing layer of the present embodiment contains a color absorber that absorbs light other than the color emitted by the color-developing layer. Specifically, the scattering layer 31 arranged on the lower side of the blue color-emitting layer of the present embodiment contains a green absorber and a red absorber. The scattering layer 31 disposed below the green color-emitting layer contains a blue absorber and a red absorber. The scattering layer 31 disposed below the red color-emitting layer contains a blue absorber and a green absorber. In addition, about the red absorber and green absorber, the compound demonstrated in the description of 4th Embodiment is used suitably. Furthermore, as the blue absorber, those selected from C.I. Pigment Yellow 150, C.I. Pigment Yellow 213, C.I. Pigment Yellow 215, C.I. Pigment Yellow 185, C.I. Pigment Yellow 138, C.I. Pigment Yellow 139, C.I. Solvent Yellow) 21, C.I. Solvent Yellow 82, C.I. Solvent Yellow 83:1, C.I. Solvent Yellow 33, C.I. Solvent Yellow 162 At least one yellow organic dye pigment in the group consisting of. That is, in the present embodiment, in the color-emitting layer 33 in the fourth embodiment, blue light and green light that are not absorbed by the QDs of the respective colors are absorbed by the lower scattering layer 31, whereby the effect of preventing these Light is emitted from the pixels again, and the color purity of each pixel is prevented from degrading. At the same time, in the color-forming layer 33 in the fourth embodiment, when the concentration of scattering particles or the concentration of the absorber becomes too high in a single layer, these are separated to provide another layer ( scattering layer 31), the present embodiment also exhibits the same effects as those of the fourth embodiment.

<Modification 9>

The sixth embodiment has been described on the premise that the blue color-emitting layer does not contain scattering particles but blue QDs, and the green color-emitting layer does not contain scattering particles While green QDs are included, the red chromophoric layer does not include scattering particles but includes red QDs. However, each color-developing layer is not limited to this. Scattering particles may be included in each chromonic layer. In addition, the density|concentration of the scattering particle|grains in this case is the density|concentration in the range which each color-developing layer can be comprised as a single layer. This modification also exhibits the same effects as those of the fifth embodiment. Furthermore, in the present modification, by further including scattering particles in each color-developing layer, it is possible to further scatter light and further reduce the visual dependence of color compared with the sixth embodiment.

<Variation 10>

In the fourth embodiment to the sixth embodiment and the modified examples thereof, the following description is made: the prepared composition containing each QD is applied on the reflective layer 27 and the opening of the bank layer 25 is applied to the openings of the bank layer 25 by This forms the color-emitting layer 33 . However, the method of forming the color-developing layer 33 is not limited to this. For example, the color-developing layer 33 can also be formed by coating with ink jet. As the inkjet composition, known QD compositions (eg, Japanese Patent Laid-Open No. 2010-9995, Japanese Patent Laid-Open No. 2009-76282, etc.) can be used. This modification also exhibits the same effects as those of the above embodiment.

<Variation 11>

The fourth embodiment to the sixth embodiment and the modified examples thereof have been described on the premise that a transistor layer exists, that is, an active matrix driving method. However, the driving method is not limited to this, and can be appropriately changed according to the purpose. For example, in order to provide an inexpensive display device, a known simple matrix method can also be used. In addition, a well-known segment drive method can also be used. In this way, the electronic label previously displayed in monochrome can be turned into a high-quality color electronic label. Furthermore, in the above-mentioned embodiment and modification, the transistor was demonstrated on the premise that the transistor is a so-called reverse staggered type. However, it is not limited Here, the staggered type may also be used. According to this modification, the same effects as those of the fourth embodiment are exhibited.

<Variation 12>

The fourth embodiment to the sixth embodiment and the modified examples thereof have been described on the premise that the light-adjusting layer 40 is of an electrowetting method. However, the dimming layer 40 is not limited to this, and a mechanical shutter (mechanical shutter) using the well-known Micro Electro Mechanical Systems (MEMS) technology can also be used. This modification also exhibits the same effects as those of the first embodiment.

<Variation 13>

The fourth to sixth embodiments have been described on the premise that the first partition wall material 53 and the second partition wall material 55 are present. However, the number of partition wall materials may not be two but one or three or more.

In addition, this invention is not limited to the said embodiment, It can change suitably in the range which does not deviate from the summary.

11: The first substrate

13: Gate electrode

15: Gate insulating film

17: Semiconductor layer

19: source electrode

21: drain electrode

20: Thin Film Transistor

23: Passivation layer

25: Embankment Layer

26: Sidewall

27: Reflective layer

29: wiring layer

33: Hair Color Layer

34: outer coating

35: 1st transparent electrode

37: Black matrix. spacer

39: The first alignment film

41: Second alignment film

43: Second transparent electrode

45: Second substrate

46: Liquid crystal layer

47: Liquid crystal molecules

49: Dichroic Pigments

L _i : Incident light

L _o : outgoing light

Claims (26)

A display device comprising: a first substrate, a second substrate arranged to face the first substrate, and a first substrate arranged between the first substrate and the second substrate on the side of the first substrate Transparent electrode, second transparent electrode disposed between the first substrate and the second substrate on the side of the second substrate, reflective layer between the first substrate and the first transparent electrode, disposition a liquid crystal layer having a light-adjusting function between the first transparent electrode and the second transparent electrode, a color-emitting layer disposed between the first transparent electrode and the reflective layer, and a color-emitting layer disposed between the first transparent electrode and the reflective layer A bank layer having an opening between the first substrate and the liquid crystal layer, the reflective layer is disposed on the side wall of the bank layer on the side of the opening, and the incident light incident from the second substrate The color and the color of the outgoing light reflected by the reflective layer and emitted from the second substrate side are different from each other. The display device according to claim 1, wherein the liquid crystal layer is a guest-host liquid crystal layer comprising liquid crystal molecules and dichroic dyes. The display device according to claim 2, wherein the guest-host liquid crystal layer is a Heilmeier liquid crystal layer, a vertical alignment liquid crystal layer containing a chiral component, a liquid crystal layer with a cholesterol blue phase, and a polymer dispersed liquid crystal layer. type of liquid crystal layer. The display device of claim 1, wherein the color-emitting layer includes quantum dots. The display device according to claim 4, further comprising a scattering layer that is disposed between the reflective layer and the color-emitting layer and that scatters incident light. The display device according to claim 5, wherein the color-emitting layer includes a blue color-emitting layer, a red color-emitting layer, and a green color-emitting layer, the blue color-emitting layer includes blue quantum dots, and the The red color-emitting layer includes red quantum dots, the green color-emitting layer includes green quantum dots, and the scattering layer between the blue color-emitting layer and the reflection layer includes a green absorber and a red absorber. The scattering layer between the red color-emitting layer and the reflective layer includes a blue absorber and a green absorber, and the scattering layer between the green color-emitting layer and the reflecting layer includes a blue absorber and green absorbent. The display device according to claim 6, wherein the blue absorber is selected from the group consisting of C.I. Pigment Yellow 150, C.I. Pigment Yellow 213, C.I. Pigment Yellow 215, C.I. Pigment Yellow 185, C.I. Pigment Yellow 138, C.I. Pigment At least one yellow organic dye pigment in the group consisting of Yellow 139, C.I. Solvent Yellow 21, C.I. Solvent Yellow 82, C.I. Solvent Yellow 83:1, C.I. Solvent Yellow 33, and C.I. Solvent Yellow 162. The display device according to claim 1, wherein the display device The color layer includes a blue color-emitting layer, a red color-emitting layer and a green color-emitting layer. The display device of claim 8, wherein the red color-emitting layer includes quantum dots, the green color-emitting layer includes quantum dots and a red absorber, and the blue color-emitting layer includes a green absorber and red absorbent. The display device of claim 8, wherein the blue color-emitting layer further comprises scattering particles. The display device according to claim 10, wherein the red color-emitting layer and the green color-emitting layer further comprise scattering particles, respectively. The display device according to claim 1, wherein the sidewalls are tapered in cross-sectional view. A display device comprising: a first substrate, a second substrate arranged to face the first substrate, and a first substrate arranged between the first substrate and the second substrate on the side of the first substrate Transparent electrode, second transparent electrode disposed between the first substrate and the second substrate on the side of the second substrate, reflective layer between the first substrate and the first transparent electrode, disposition Between the first transparent electrode and the second transparent electrode, a layer containing charged particles or liquid and having a light-adjusting function, and a light-emitting device disposed between the first transparent electrode and the reflective layer a color layer, and a bank layer disposed between the first substrate and the liquid crystal layer and having an opening, The reflective layer is disposed on the side wall of the bank layer on the side of the opening, and the color of the incident light incident from the second substrate side and the color of the incident light reflected by the reflective layer and emitted from the second substrate side The colors of the outgoing light are different from each other. The display device according to claim 13, wherein the layer having a dimming function comprises: a hydrophobic film disposed on the first transparent electrode; The partition material, the non-polar first liquid and the polar second fluid arranged in the region partitioned by the first partition material. The display device according to claim 14, wherein the layer having a dimming function further comprises a second partition wall material disposed on the first partition wall material, and the first partition wall material is relatively The wettability of the first liquid is high, and the wettability of the second partition wall material to the first liquid is low. A display device comprising: a first substrate, a second substrate arranged to face the first substrate, and a first substrate arranged between the first substrate and the second substrate on the side of the first substrate Transparent electrode, second transparent electrode disposed between the first substrate and the second substrate on the side of the second substrate, reflective layer between the first substrate and the first transparent electrode, disposition MEMS between the first transparent electrode and the second transparent electrode A system mechanical shutter, a color-emitting layer disposed between the first transparent electrode and the reflective layer, and a bank layer disposed between the first substrate and the liquid crystal layer and having an opening, the reflective layer disposed The sidewall of the bank layer on the side of the opening, the color of the incident light from the second substrate side, and the color of the outgoing light reflected by the reflective layer and emitted from the second substrate side different from each other. The display device according to claim 13 or claim 16, wherein the color-emitting layer comprises quantum dots. The display device according to claim 17, further comprising a scattering layer that is disposed between the reflective layer and the color-emitting layer and that scatters incident light. The display device according to claim 18, wherein the color-emitting layer includes a blue color-emitting layer, a red color-emitting layer and a green color-emitting layer, the blue color-emitting layer includes blue quantum dots, and the The red color-emitting layer includes red quantum dots, the green color-emitting layer includes green quantum dots, and the scattering layer between the blue color-emitting layer and the reflection layer includes a green absorber and a red absorber. The scattering layer between the red color-emitting layer and the reflective layer includes a blue absorber and a green absorber, and the scattering layer between the green color-emitting layer and the reflecting layer includes a blue absorber and green absorbent. The display device of claim 19, wherein the blue absorber is selected from the group consisting of C.I. Pigment Yellow 150, C.I. Pigment Yellow 213, C.I. Pigment Yellow 215, C.I. Pigment Yellow 185, C.I. Pigment Yellow 138, C.I. Pigment At least one yellow organic dye pigment in the group consisting of Yellow 139, C.I. Solvent Yellow 21, C.I. Solvent Yellow 82, C.I. Solvent Yellow 83:1, C.I. Solvent Yellow 33, and C.I. Solvent Yellow 162. The display device according to claim 13 or 16, wherein the color-emitting layer comprises a blue color-emitting layer, a red color-emitting layer, and a green color-emitting layer. The display device of claim 21, wherein the red color-emitting layer includes quantum dots, the green color-emitting layer includes quantum dots and a red absorber, and the blue color-emitting layer includes a green absorber and red absorbent. The display device of claim 21, wherein the blue color-emitting layer further includes scattering particles. The display device according to claim 23, wherein the red color-emitting layer and the green color-emitting layer further comprise scattering particles, respectively. The display device according to claim 13 or claim 16, wherein the color-emitting layer comprises a fluorescent substance. The display device according to claim 13 or claim 16, wherein the side wall is tapered in cross-sectional view.

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