WO2025206435A1 - Display device, integrated coating film for same, and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a display device and a manufacturing method thereof. A display device according to an embodiment of the present invention comprises: a wiring substrate; a first wiring electrode and a second wiring electrode arranged on the wiring substrate; a first electrode pad and a second electrode pad connected to the first wiring electrode and the second wiring electrode, respectively; a light-emitting element electrically connected to the first electrode pad and the second electrode pad and installed to form a sub-pixel in each of the unit pixel regions; and a coating film positioned on the light-emitting element, wherein the coating film includes a black coating layer positioned on the wiring substrate to cover at least a portion of a side surface of the light-emitting element, a transparent coating layer positioned on the black coating layer, and an optical layer positioned on the transparent coating layer.

Description

Display device, integrated coating film therefor, and manufacturing method thereof

The present disclosure relates to a display device and a method for manufacturing the same.

In recent years, display devices with superior characteristics, such as thinness and flexibility, have been developed in the field of display technology. Currently, the major commercially available displays are represented by LCD (Liquid Crystal Display) and OLED (Organic Light Emitting Diode).

Meanwhile, a light-emitting diode (LED) is a semiconductor light-emitting device that is well known for converting electric current into light. Starting with the commercialization of a red LED using GaAsP compound semiconductors in 1962, it has been used as a light source for display images in electronic devices, including information and communication devices, along with green LEDs of the GaP:N series.

Recently, these light-emitting diodes (LEDs) have been gradually miniaturized and manufactured into millimeter- or micrometer-sized LEDs, which are used as pixels in display devices.

Compared to other display devices/panels, this type of LED technology boasts low power consumption, high brightness, and high reliability, and can also be applied to flexible devices. Therefore, research institutes and companies have been actively researching this technology recently.

The LED display market is expanding into diverse applications that leverage the high brightness and high reliability of LEDs. One of the sectors leading the market with these characteristics is signage displays.

When manufacturing a display using these LEDs, a sealing layer (coating layer) is formed using a polymer material such as silicone to protect the LEDs that form the light source.

For example, the process of forming such an encapsulating layer involves applying an encapsulating material, such as silicone, onto a light source using jet dispensing, followed by a lapping process to achieve surface flatness after curing the encapsulating material. This process polishes the surface of the encapsulating material using friction.

However, the surface flattening process and the wrapping process for grinding the surface of the sealing material to achieve the target thickness require additional process time and cost, and this may result in loss of silicon material.

Additionally, after this surface processing, a film attachment process is additionally required to protect the surface.

Therefore, an efficient process for forming a sealing layer (coating layer) and a structure that can stably protect a light source are required.

The present disclosure provides a display device capable of reducing the process time and material consumption required to form each coating layer, an integrated coating film therefor, and a method for manufacturing the same.

In addition, the present invention seeks to provide a display device capable of emitting uniform light from individual light-emitting elements by taking into account side light emitted from the light-emitting elements, an integrated coating film therefor, and a method for manufacturing the same.

In addition, the present invention aims to provide a display device that does not require a separate adhesive layer for bonding a black coating layer, a transparent coating layer, and an optical layer on a support film layer, an integrated coating film therefor, and a manufacturing method thereof.

Meanwhile, when filler particles are provided in a transparent coating layer, a display device in which filler particles can be uniformly distributed within a transparent coating layer or a scattering layer, an integrated coating film therefor, and a manufacturing method thereof are provided.

A display device according to an embodiment of the present disclosure includes: a wiring substrate; a first wiring electrode and a second wiring electrode arranged on the wiring substrate; a first electrode pad and a second electrode pad respectively connected to the first wiring electrode and the second wiring electrode; a light-emitting element electrically connected to the first electrode pad and the second electrode pad in each unit pixel area to form a subpixel; and a coating film positioned on the light-emitting element, wherein the coating film may include: a black coating layer positioned on the wiring substrate and covering at least a portion of a side surface of the light-emitting element; a transparent coating layer positioned on the black coating layer; and an optical layer positioned on the transparent coating layer.

A method for manufacturing a modular display device according to an embodiment of the present disclosure may include the steps of: preparing a substrate assembly in which unit light-emitting elements are arranged on a wiring board; manufacturing a coating film in which at least a portion is in a semi-cured state; bonding a semi-cured portion of the coating film onto the substrate assembly; and separating the substrate assembly into individual unit modules.

An integrated coating film bonded to a wiring board on which light sources are arranged according to an embodiment of the present disclosure may include a black coating layer in a semi-cured (B-stage) state positioned on a release film; a transparent coating layer in a semi-cured (B-stage) state positioned on the black coating layer; a support film layer positioned on the transparent coating layer; and an optical layer positioned on the support film layer.

According to at least one of the various embodiments of the present disclosure, by applying a coating film that is at least partially in a semi-cured state (B-stage), the process time and material consumption required to form each coating layer can be reduced. For example, the dispensing and subsequent wrapping (flattening) processes required when forming a coating film using a liquid coating material can be eliminated.

In addition, since the height of the black coating layer can be easily adjusted, uniform light can be emitted from each light-emitting element by taking into account the side light emitted from the light-emitting element.

Additionally, no separate adhesive layer is required to adhere the black coating layer, transparent coating layer, and optical layer to the support film layer. This is because the semi-cured (B-stage) material itself has adhesive strength.

Meanwhile, when filler particles are provided in the transparent coating layer, the filler particles can be uniformly distributed within the transparent coating layer or the scattering layer. Meanwhile, it is also possible to distribute the filler particles at a higher density on the upper surface within the transparent coating layer or the scattering layer.

In addition to the effects described above, the specific effects of the present disclosure are described below together with specific details.

Fig. 1 is a cross-sectional schematic diagram showing a display device according to a first embodiment of the present disclosure.

Fig. 2 is a cross-sectional photograph showing a display device according to the first embodiment of the present disclosure.

FIG. 3 is a cross-sectional view of an integrated coating film applied to a display device according to the first embodiment of the present disclosure.

Fig. 4 is a cross-sectional photograph showing a display device according to a comparative example.

FIGS. 5 to 9 are cross-sectional views showing a manufacturing process of an integrated coating film applied to a display device according to the first embodiment of the present disclosure.

Fig. 10 is a cross-sectional view showing a display device according to a second embodiment of the present disclosure.

FIG. 11 and FIG. 12 are photographs showing filler particles according to one embodiment of the present disclosure.

FIGS. 13 to 16 are cross-sectional views showing a manufacturing process of a display device according to the first embodiment of the present disclosure.

Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings. The suffixes "module" and "part" used in the following description for components are assigned or used interchangeably solely for the convenience of writing the specification, and do not in themselves have distinct meanings or roles.

Additionally, when describing the embodiments disclosed in this specification, detailed descriptions of related known technologies will be omitted if it is determined that such detailed descriptions may obscure the gist of the embodiments disclosed in this specification. Furthermore, it should be noted that the attached drawings are intended only to facilitate understanding of the embodiments disclosed in this specification, and should not be construed as limiting the technical concepts disclosed in this specification.

Furthermore, for the convenience of explanation, each drawing is described, but it is also within the scope of the present invention for a person skilled in the art to implement another embodiment by combining at least two drawings.

Additionally, when an element such as a layer, region or substrate is referred to as existing "on" another element, it will be understood that this may be directly on the other element, or that there may be intermediate elements in between.

The display device described in this specification is a concept that includes all display devices that display information as a unit pixel or a set of unit pixels. Therefore, it can be applied not only to finished products but also to components. For example, a panel corresponding to a component of a digital TV is also a display device in this specification. Finished products may include mobile phones, smart phones, laptop computers, digital broadcasting terminals, personal digital assistants (PDAs), portable multimedia players (PMPs), navigation systems, slate PCs, tablet PCs, Ultrabooks, digital TVs, desktop computers, etc.

However, it will be readily apparent to those skilled in the art that the configuration according to the embodiments described herein may be applied to any device capable of displaying, even if it is a new product type developed in the future.

In addition, the semiconductor light-emitting device mentioned in the specification includes LED, mini LED, micro LED, etc., and may be used interchangeably.

Fig. 1 is a cross-sectional schematic diagram showing a display device according to a first embodiment of the present disclosure.

Referring to FIG. 1, a display device (10) may be configured such that individual unit pixel areas (200) are defined on a wiring board (100), and a plurality of light-emitting elements (210, 220, 230) forming unit light sources are installed within the unit pixel areas (200).

Here, individual light-emitting elements (210, 220, 230) installed in a unit pixel area (200) may substantially correspond to subpixels. For example, three subpixels may be gathered together to form one pixel. In Fig. 1, the three light-emitting elements (210, 220, 230) may correspond to red, green, and blue light-emitting elements, respectively.

Each light emitting element (210, 220, 230) can be electrically connected to a pair of electrode pads (130, 140/131, 141/132, 142). In this case, for example, the electrode pads (130, 131, 132: hereinafter, first electrode pads) arranged in one direction in FIG. 1 can be connected to the first wiring electrodes (121, 122, 123; signal electrodes or data electrodes).

In addition, the electrode pads (140, 141, 142: hereinafter, second electrode pads) arranged in the other direction can be connected to the second wiring electrode (124; common electrode or scan electrode). However, the opposite case is also possible. In Fig. 1, signal electrodes (121, 122, 123) and the common electrode (124) are omitted in terms of the arrangement of the electrodes and electrode pads.

Meanwhile, in some cases, the first electrode pad (130, 131, 132) may correspond to a signal electrode (121, 122, 123), and the second electrode pad (140, 141, 142) may correspond to a common electrode (124).

Hereinafter, the drawing symbols for electrode pads and wiring electrodes are used interchangeably. That is, the electrode pads and wiring electrodes can be described using the same drawing symbols.

In this way, a unit subpixel can be defined at the point where the first wiring electrode (121, 122, 123) and the second wiring electrode (124) intersect each other.

Meanwhile, when the light-emitting elements (210, 220, 230) are driven in an Active Matrix (AM) manner and the first wiring electrodes (121, 122, 123) are signal electrodes (or data electrodes), the first wiring electrodes (121, 122, 123, or the first electrode pads (130, 131, 132)) may be connected to a TFT layer (120) equipped with a thin film transistor (TFT). Accordingly, each of the light-emitting elements (210, 220, 230) may be driven by switching driving by the TFT layer (120).

In FIG. 1, the TFT layer (120) is briefly illustrated as a single layer, but the TFT layer (120) may include a plurality of TFT regions capable of performing a switching operation. For example, each TFT region may include a gate electrode, a source electrode, a drain electrode, an insulating layer positioned therebetween, a via electrode that may be connected to a first wiring electrode (121, 122, 123, or a first electrode pad (130, 131, 132)), etc. A detailed description thereof is omitted. Each of these TFT regions may be connected to a respective light-emitting element (210, 220, 230).

A plurality of light-emitting elements (200; 210, 220, 230) can be installed electrically connected to form individual subpixels on these wiring electrodes (121, 122, 123, 124).

Meanwhile, when the light-emitting element (210, 220, 230) is driven in a passive matrix (PM) manner, the TFT layer (120) may be omitted.

As mentioned above, the unit pixel (200) may include a red light-emitting element (210), a green light-emitting element (220), and a blue light-emitting element (230), and these three light-emitting elements (210, 220, 230) may form individual subpixels and be repeatedly positioned on the wiring board (100). The light-emitting elements (210, 220, 230) may include at least one of an organic light-emitting element and an inorganic light-emitting element. For example, the light-emitting elements (210, 220, 230) may be inorganic semiconductor light-emitting elements (Light Emmitting Diodes; LEDs).

For example, such semiconductor light emitting devices (LEDs; 200) may have a size in units of millimeters (mm) or micrometers (㎛). Here, a size in units of micrometers (㎛) may mean that the width of at least one side of the light emitting device (200) has a size of several to several hundred micrometers (㎛).

The light emitting elements (210, 220, 230) may each include a first type electrode (e.g., an n-type electrode; 211, 221, 231) and a second type electrode (e.g., a p-type electrode; 212, 222, 232). These first type electrodes (211, 221, 231) and second type electrodes (212, 222, 232) may be electrically connected to a pair of electrode pads (130, 140/131, 141/132, 142) by solder (240).

In this way, a coating film (encapsulation layer; 150) may be positioned on the wiring board (100) on which the light-emitting elements (210, 220, 230) are arranged. This coating film (150) may perform at least one of the functions of an insulating layer that insulates the electrical connection portions of the light-emitting elements (210, 220, 230) and a function of flattening the installation portions of the light-emitting elements (210, 220, 230).

Such a coating film (150) may include a black coating layer (151) positioned on a wiring board (100) and covering at least a portion of a light emitting element (210, 220, 230).

The black coating layer (151) may have a height corresponding to at least a portion of the side portion of the light emitting element (210, 220, 230). For example, the black coating layer (151) may cover at least a portion of the side portion of the light emitting element (210, 220, 230). For example, as illustrated in FIG. 1, the upper surface of the black coating layer (151) may be positioned at a certain height that does not completely cover the side portion of the light emitting element (210, 220, 230). This black coating layer (151) may improve the contrast ratio of the display device (10). That is, the black coating layer (151) may improve the black color of the display device (10).

For example, the material of the black coating layer (151) may be in the form of a black powder mixed with at least one of silicone, acrylic, urethane, and epoxy polymers. The thickness of this black coating layer may be smaller than the thickness of the light-emitting element (210, 220, 230) (for example, 150 μm or less).

The transmittance of this black coating layer (151) may be 80% or less. For example, when the transmittance exceeds 80%, the blackness improvement effect may be low.

The black powder included in the black coating layer (151) may include an organic or inorganic dye or pigment (carbon black, etc.). The shape of the black powder may be spherical or amorphous. The diameter of the black powder may be 10 nm to 20 μm.

As described above, the coating film (150) can serve as an insulating layer that insulates the electrical connection portions of the light-emitting elements (210, 220, 230). At this time, the black coating layer (151) included in the coating film (150) can also serve as an insulating layer that insulates the electrical connection portions of the light-emitting elements (210, 220, 230). In addition, the black coating layer (151) can prevent the metal electrode pads (130, 140/131, 141/132, 142) from being reflected by external light and emitting reflected light.

In some cases, a separate insulating layer (159) may be positioned under the black coating layer (151). For example, the separate insulating layer (159) may serve as an insulating layer that insulates the electrical connection portions of the light-emitting elements (210, 220, 230).

The coating film (150) may include a transparent coating layer (152) positioned on a black coating layer (151). The transparent coating layer (152) may serve as a transmitting layer through which light emitted from a light-emitting element (210, 220, 230) is transmitted, as a scattering layer, or as a role of preventing damage caused by external force.

The transparent coating layer (152) can be manufactured using at least one of silicone, acrylic, urethane, and epoxy polymers. The transparent coating layer (152) may include filler particles (158; see FIG. 10). The filler particles may act as a light scattering agent. Meanwhile, a separate scattering layer containing a light scattering agent may be provided separately from the transparent coating layer (152). The thickness of the transparent coating layer (152) or the scattering layer may be 20 μm. The thickness of the transparent coating layer (152) may be 300 μm or less.

The filler particles (158) may have optical properties that refract or scatter light emitted from the light-emitting elements (210, 220, 230). The light emitted from the light-emitting elements (210, 220, 230) may be refracted or scattered by at least one of the transparent coating layer (152), the scattering layer, and the filler particles (158). The light scattered by the filler particles (158) may be emitted to the outside of the coating film (150).

The coating film (150) may have light-transmitting properties after being cured. For example, the cured coating film (150) including silicone may have a refractive index of 1.4 to 1.6. Accordingly, light may be totally reflected within the coating film (150). The filler particles (158) may refract or scatter light that is totally reflected within the coating film (150).

In this way, the filler particles (158) can act as a light scattering agent. Therefore, the filler particles (158) can be referred to as a light scattering agent. In the following description, the filler particles and the light scattering agent may refer to the same entity. By mixing such light scattering agents (158), the color viewing angle of the display device (10) can be improved. In addition, filler particles (158) having a high scattering effect with a small amount of light scattering agent (158) can be used.

These filler particles (158) may include at least one of Zr, Si, Ti, Zn, BaS, and oxides thereof. For example, the filler particles (158) may be spherical or amorphous (see FIGS. 11 and 12). The diameter of the filler particles (158) may be 20 nm to 7 μm based on D50 (medium size).

The diameter or size of the filler particles (158) may be 10 nanometers (nm) to 10 micrometers (㎛). The content (weight ratio) of these filler particles (158) may be 0.01% to 30% relative to the transparent coating layer (152). If the content of the filler particles (158) exceeds 30%, implementation may be difficult due to an increase in viscosity.

For example, the transparent coating layer (152) may include at least one of Zr oxide and Si oxide. For example, a plurality of scattering agents may be included in one layer, and may be provided as a plurality of layers each including a scattering agent.

Although not shown separately, a modular display device may be implemented in which multiple display devices (10) are combined to realize a larger display area. For example, the display device (10) may be a single display module forming a modular display device. In this way, multiple display devices (10) may be combined in parallel to form a modular display device. A detailed description thereof will be omitted.

A support film layer (153) may be positioned on the transparent coating layer (152). This support film layer (153) may perform at least one of the following roles: protecting the light-emitting elements (210, 220, 230), acting as a light-transmitting transparent layer, and supporting the coating film (150). For example, the support film layer (153) may enhance the role of protecting the light-emitting elements (210, 220, 230).

This support film layer (153) may include at least one material among PET (Poly Ethylene Terephthalate), CPI (Clear Polyimide), and PU (Poly Urethane).

The thickness of the support film layer (153) may be 20 to 150 μm. A thickness of 20 μm or more may be required for the function of the support film layer (153) described above. Meanwhile, a thickness of 150 μm or more may cause a line to appear in the display device (10).

An optical layer (154) may be positioned on the support film layer (153). For example, this optical layer (154) may constitute a composite optical film. In this way, the optical layer (154) may be formed directly on the support film layer (153). For example, according to the present embodiment, the optical layer (154) may be in direct contact with the support film layer (153). That is, a separate adhesive layer may not exist between the optical layer (154) and the support film layer (153).

The optical layer (154) may, as an exemplary embodiment, include anti-glare (AG) and anti-fingerprint (AF) functions. For example, the optical layer (154) may include at least one of an anti-glare (AG) coating layer and an anti-fingerprint (AF) coating layer.

At least a portion of such a coating film (150) may be provided as an integral part in a semi-cured state (B-stage). For example, at least a portion of the black coating layer (151), the transparent coating layer (152), the support film layer (153), and the optical layer (154) forming the coating film (150) may be provided as an integral part in a semi-cured state and may be bonded onto a wiring board (100) on which light-emitting elements (210, 220, 230) are mounted.

For example, a black coating layer (151) and a transparent coating layer (152) are integrated with a support film layer (153) in a semi-cured state to form an integrated coating film (150) that is bonded to a wiring board (100) on which light-emitting elements (210, 220, 230) are mounted, and then completely cured (C-stage) to form a structure of a display device (10) as shown in FIG. 1.

In this way, the black coating layer (151) and the transparent coating layer (152) are positioned in a semi-cured state on the support film layer (153), and an optical layer (154) is formed on the support film layer (153) to form an integrated coating film (150).

At this time, as an exemplary embodiment, at least one of the black coating layer (151) and the transparent coating layer (152) may be optional. For example, at least one of the black coating layer (151) and the transparent coating layer (152) may be omitted.

By applying a coating film (150) that is at least partially in a semi-cured state (B-stage), the process time and material consumption required to form each coating layer can be reduced. Typically, when forming a coating film using a liquid coating material, the dispensing and subsequent wrapping (flattening) processes can require time and materials.

However, according to the present disclosure, a highly reliable display device (10) can be implemented by a coating film (150) having high heat resistance properties compared to conventional liquid coating materials.

Since the height of the black coating layer (151) can be easily adjusted, uniform light can be emitted from each light emitting element (210, 220, 230) by taking into account the side light emitted from the light emitting element (210, 220, 230).

In addition, a separate adhesive layer is not required to adhere the black coating layer (151), the transparent coating layer (152), and the optical layer (154) on the support film layer (153). This is because the material in the semi-cured state (B-stage) itself has adhesive strength.

Meanwhile, when filler particles (158) are provided in the transparent coating layer (152), the filler particles (158) can be uniformly distributed within the transparent coating layer (152) or the scattering layer. Meanwhile, it is also possible to distribute the filler particles (158) at a higher density on the upper surface within the transparent coating layer (152) or the scattering layer.

In general, when distributing filler particles using a liquid material, the distribution of filler particles tends to be concentrated on the lower side due to the influence of gravity.

Fig. 2 is a cross-sectional photograph showing a display device according to the first embodiment of the present disclosure. Fig. 3 is a cross-sectional photograph of an integrated coating film applied to a display device according to the first embodiment of the present disclosure. Fig. 4 is a cross-sectional photograph showing a display device according to a comparative example.

Referring to FIG. 2, an example of a display device (10) is illustrated in which an integrated coating film (150) in a semi-cured state, at least partially described above, is bonded to a wiring board (100) equipped with light-emitting elements (210, 220, 230).

In FIG. 2, the black coating layer (151), the transparent coating layer (152), the support film layer (153), and the optical layer (154) are indicated as black coating, transparent coating, PET film, and AG coating, respectively.

In this way, as an exemplary embodiment, the black coating layer (151) and the transparent coating layer (152) are integrated with the support film layer (153) in a semi-cured state to form an integrated coating film (150) that is bonded onto a wiring board (100) on which light-emitting elements (210, 220, 230) are mounted, and then completely cured (C-stage) to form a structure of a display device (10) as shown in FIG. 2.

Referring to FIG. 3, a black coating layer (151) and a transparent coating layer (152) are laminated and positioned in a semi-cured state on one side of a support film layer (153), and an optical layer (154) is coated on the other side of the support film layer (153) to form an integrated coating film.

In this case, the upper surface (1511) of the black coating layer (151) may form a surface parallel to the upper surface of the light-emitting element (LED chip). That is, the upper surface (1511) of the black coating layer (151) may form a flat surface parallel to the wiring board (100).

For example, since the black coating layer (151) is bonded to the wiring board (100) equipped with the light-emitting element (LED chip) in a semi-cured state, the upper surface (1511) can form a substantially flat surface rather than a curved surface. Accordingly, light of uniform intensity can be emitted from each light-emitting element (210, 220, 230). In addition, since the height of the black coating layer (151) can be easily adjusted, light of uniform intensity can be emitted from each light-emitting element (210, 220, 230) in consideration of the side light emitted from the light-emitting elements (210, 220, 230).

Fig. 4 shows an example of a display device (1) in which a black coating layer (11) and a transparent coating layer (12) of a liquid material are applied on a wiring board as a comparative example.

Referring to Fig. 4, after a black coating layer (11) is formed on a wiring board using a liquid silicone material, a transparent coating layer (12) of a liquid material is coated to form a coating film (sealing layer).

At this time, since the black coating layer (11) is formed with a liquid silicone material, the upper surface (13) of the black coating layer (11) becomes curved. That is, the upper surface (13) of the black coating layer (11) forms a curved hang structure between the light-emitting elements. Accordingly, according to the comparative example, a coating of a constant height is not formed on the side of the light-emitting element. Accordingly, the uniformity of the intensity of light emitted from each light-emitting element may be reduced.

FIGS. 5 to 9 are cross-sectional views showing a manufacturing process of an integrated coating film applied to a display device according to the first embodiment of the present disclosure.

First, referring to FIG. 5, an optical layer (154) may be formed on a support film layer (153). For example, this optical layer (154) may constitute a composite optical film. In this way, the optical layer (154) may be formed directly on the support film layer (153). Therefore, according to the present embodiment, the optical layer (154) may be in direct contact with the support film layer (153). That is, a separate adhesive layer may not exist between the optical layer (154) and the support film layer (153).

The support film layer (153) may include at least one material selected from the group consisting of PET (Poly Ethylene Terephthalate), CPI (Clear Polyimide), and PU (Poly Urethane). In this way, the support film layer (153) may have a stable support substrate function. Accordingly, the optical layer (154) may be easily coated and formed on the support film layer (153).

The optical layer (153) may, as an exemplary embodiment, include anti-glare (AG) and anti-fingerprint (AF) functions. For example, the optical layer (153) may include at least one of an anti-glare (AG) coating layer and an anti-fingerprint (AF) coating layer.

Referring to Fig. 6, a black coating layer (151) may be formed on a separate carrier film (155; release film). This black coating layer (151) may be formed in a semi-cured state (B-stage) on the release film (155).

Referring to Fig. 7, a transparent coating layer (152) can be formed on a black coating layer (151). This transparent coating layer (152) can be formed in a semi-cured state (B-stage) on a black coating layer (151) in a semi-cured state (B-stage).

Generally, resin materials can be categorized into thermosetting resins and thermoplastic resins. Among these, thermosetting resins are polymers that harden when heated through a chemical reaction (cross-linking). They do not return to their original state when reheated.

The curing process of these thermosetting resins occurs in three stages. First, the A-stage is a state in which the resin and hardener are simply mixed. The B-stage, also known as the semi-cured state, is the stage in which the resin and hardener react to some extent, causing a rapid increase in viscosity and flowability. In other words, it refers to the state in which the resin and hardener meet and begin to react to form a polymer, and the state before curing. The C-stage is the stage in which the reaction between the resin and hardener is complete, and thereafter, it is unaffected by solvents and heat.

In this way, the black coating layer (151) and the transparent coating layer (152) are positioned on the release film (155) in this semi-cured state.

In some cases, as shown in FIG. 8, a protective film (156) is attached to the transparent coating layer (152).

Referring to FIG. 9, a semi-cured transparent coating layer (152) can be laminated to one side of the support film layer (153) described with reference to FIG. 5. If a protective film (156) is positioned on the transparent coating layer (152), one side of the support film layer (153) can be laminated after removing the protective film (156). For example, a transparent coating layer (152) as shown in FIG. 7 can be laminated to one side of the support film layer (153) on which the optical layer (154) is not formed.

Here, when the release film (155) is removed, the state of the integrated coating film (150) described above with reference to FIG. 3 is achieved. When the integrated coating film (150) is bonded onto the wiring board (100) to manufacture the display device (10), the release film (155) can be removed in this manner and the coating film (150) can be bonded so that the black coating layer (151) faces the upper surface of the wiring board (100).

Fig. 10 is a cross-sectional view showing a display device according to a second embodiment of the present disclosure. Figs. 11 and 12 are photographs showing filler particles according to one embodiment of the present disclosure.

Referring to Fig. 10, a display device (11) according to a second embodiment of the present disclosure is illustrated. The display device (11) according to the second embodiment is illustrated in a state in which a unit light emitting element (210) is installed on a wiring board (100).

In Fig. 10, a state in which a unit light emitting element (210) is installed on a single wiring board (100) is shown, but as in the first embodiment described above, individual unit pixel areas (200) may be divided, and a plurality of light emitting elements (210, 220, 230) forming a unit light source may be installed within the unit pixel areas (200).

Here, individual light-emitting elements (210, 220, 230) installed in the unit pixel area (200) may substantially correspond to subpixels. For example, three subpixels may be gathered together to form one pixel. The three light-emitting elements (210, 220, 230) may correspond to red, green, and blue light-emitting elements, respectively. Among these, the unit light-emitting element (210) illustrated in FIG. 10 may correspond to a red light-emitting element.

As described above, each light emitting element (210, 220, 230) can be electrically connected to a pair of electrode pads (130, 140/131, 141/132, 142). Referring to FIG. 10, the red light emitting element (210) can be electrically connected to the first electrode pad (130) and the second electrode pad (140).

In this case, for example, the first electrode pad (130) may be connected to the first wiring electrode (121; signal electrode or data electrode). In addition, the second electrode pad (140) arranged in the other direction may be connected to the second wiring electrode (124; common electrode or scan electrode). However, the opposite case is also possible. In Fig. 10, the signal electrode (121) and the common electrode (124) are omitted in terms of the arrangement of the electrodes and electrode pads. In addition, the first type electrode and the second type electrode of the light-emitting element (210), solder, etc. are omitted.

Meanwhile, when the light-emitting element (210) is driven in an Active Matrix (AM) manner and the first wiring electrode (121) is a signal electrode (or data electrode), the first wiring electrode (121, or first electrode pad (130)) may be connected to a TFT layer (120) equipped with a thin film transistor (TFT). Accordingly, each of the light-emitting elements (210, 220, 230) may be driven by switching driving by the TFT layer (120).

When the light emitting element (210, 220, 230) is driven by the Passive Matrix (PM) method, the TFT layer (120) may be omitted.

Parts not described separately may be commonly applied to the parts described above with reference to Figure 1. Below, the characteristic parts of the second embodiment will be mainly described.

In this way, a coating film (encapsulation layer; 150) may be positioned on the wiring board (100) on which the light-emitting elements (210) are arranged. This coating film (150) may perform at least one of the following functions: an insulating layer that insulates the electrical connection portion of the light-emitting elements (210) and a flattening portion of the installation portion of the light-emitting elements (210).

The black coating layer (151) may be positioned on at least a portion of the side surface of the light emitting element (210). For example, as illustrated in FIG. 10, the upper surface of the black coating layer (151) may be positioned at a certain height that does not completely cover the side surface of the light emitting element (210). This black coating layer (151) may improve the contrast ratio of the display device (10). That is, the black coating layer (151) may improve the black color of the display device (10).

As described above, the coating film (150) can serve as an insulating layer that insulates the electrical connection portion of the light-emitting element (210). In addition, the black coating layer (151) can prevent the metal electrode pads (130, 140) from being reflected by external light and emitting reflected light.

The coating film (150) may include a transparent coating layer (152) positioned on the black coating layer (151). The transparent coating layer (152) may serve as at least one of a transmission layer through which light emitted from the light-emitting element (210) is transmitted, a scattering layer, and a damage prevention layer due to external force.

The transparent coating layer (152) may be manufactured using at least one of silicone, acrylic, urethane, and epoxy polymers. The transparent coating layer (152) may include filler particles (158). These filler particles may act as a light scattering agent. Meanwhile, a separate scattering layer containing a light scattering agent may be provided separately from the transparent coating layer (152).

The filler particles (158) may have optical properties that refract or scatter light emitted from the light-emitting element (210). The light emitted from the light-emitting element (210) may be refracted or scattered by at least one of the transparent coating layer (152), the scattering layer, and the filler particles (158). The light scattered by the filler particles (158) may be emitted to the outside of the coating film (150).

The coating film (150) may have light-transmitting properties after being cured. For example, the cured coating film (150) including silicone may have a refractive index of 1.4 to 1.6. Accordingly, light may be totally reflected within the coating film (150). The filler particles (158) may refract or scatter light that is totally reflected within the coating film (150).

In this way, the filler particles (158) can act as a light scattering agent. Therefore, the filler particles (158) can be referred to as a light scattering agent. In the following description, the filler particles and the light scattering agent may refer to the same entity. By mixing such light scattering agents (158), the color viewing angle of the display device (10) can be improved. In addition, filler particles (158) having a high scattering effect with a small amount of light scattering agent (158) can be used.

These filler particles (158) may include at least one of Zr, Si, Ti, Zn, BaS, and oxides thereof. For example, the filler particles (158) may be spherical, as illustrated in FIG. 11. As another example, the filler particles (158) may be amorphous, as illustrated in FIG. 12. Alternatively, the filler particles (158) may be amorphous.

For example, the transparent coating layer (152) may include at least one of Zr oxide and Si oxide. For example, a plurality of scattering agents may be included in one layer, and may be provided as a plurality of layers each including a scattering agent.

Here, an optical layer (157) may be directly formed on the transparent coating layer (152). For example, the optical layer (157) may include an anti-glare (AG) pattern. In this way, when the optical layer (157) including the AG pattern is formed on the transparent coating layer (152), the support film layer (153) of the first embodiment described with reference to FIG. 1 may not be provided separately. For example, the transparent coating layer (152) may also function as the support film layer (153).

In this way, since the AG pattern can be directly formed on the transparent coating layer (152), the coating film (150) can be implemented without a support film layer.

The optical layer (157) may, as an exemplary embodiment, include an anti-fingerprint (AF) function.

At least a portion of such a coating film (150) may be provided as an integral part in a semi-cured state (B-stage). For example, at least a portion of the black coating layer (151) and the transparent coating layer (152) forming the coating film (150) may be provided as an integral part in a semi-cured state and attached to a wiring board (100) on which a light-emitting element (210) is mounted.

For example, a black coating layer (151) and a transparent coating layer (152) are formed into an integrated coating film (150) in a semi-cured state and are bonded onto a wiring board (100) equipped with a light-emitting element (210), and then completely cured (C-stage) to form a structure of a display device (11) as shown in FIG. 10.

In this way, the black coating layer (151) and the transparent coating layer (152) are positioned in a semi-cured state, and an optical layer (157) is formed on the semi-cured transparent coating layer (152) to form an integrated coating film (150).

Accordingly, the transparent coating layer (152) can be in direct contact with the optical layer (157). That is, a separate adhesive layer may not be required between the transparent coating layer (152) and the optical layer (157).

By applying a coating film (150) that is at least partially in a semi-cured state (B-stage), the process time and material consumption required to form each coating layer can be reduced. Typically, when forming a coating film using a liquid coating material, the dispensing and subsequent wrapping (flattening) processes can require time and materials.

However, according to the present disclosure, a highly reliable display device (11) can be implemented using a coating film (150) having high heat resistance properties compared to conventional liquid coating materials.

Since the height of the black coating layer (151) can be easily adjusted, uniform light can be emitted from each light emitting element (210) by taking into account the side light emitted from the light emitting element (210).

In addition, a separate adhesive layer is not required to bond the black coating layer (151) and the transparent coating layer (152). This is because the material in the semi-cured state (B-stage) itself has adhesive strength.

Meanwhile, when filler particles (158) are provided in the transparent coating layer (152), the filler particles (158) can be uniformly distributed within the transparent coating layer (152) or the scattering layer. Meanwhile, it is also possible to distribute the filler particles (158) at a higher density on the upper surface within the transparent coating layer (152) or the scattering layer.

FIGS. 13 to 16 are cross-sectional views showing a manufacturing process of a display device according to the first embodiment of the present disclosure.

Hereinafter, with reference to FIGS. 13 to 16, a process for manufacturing a display device or a display device module using an integrated coating film (150) will be described.

First, referring to FIG. 13, a substrate assembly (100; wiring board) in which unit light emitting elements (210, 220, 230) are arranged on a substrate (110) can be prepared. In an independent process, a coating film (150) in which at least a portion is semi-cured can be manufactured.

In this way, in a state where a wiring board (100) on which unit light emitting elements (210, 220, 230) are assembled and a coating film (150) of which at least a portion is in a semi-cured state are prepared, the coating film (150) can be bonded onto the board assembly (100).

At this time, this bonding process can be accomplished by applying at least one of heat and pressure.

For example, first, a coating film (150) can be positioned on a substrate assembly (100) and pressure can be applied along with heat. At this time, heat can be applied while a plate (300) is positioned on the coating film (150).

Additionally, as shown in Fig. 14, pressure (press) can be applied toward the coating film (150) using a plate (300).

Through this process, a semi-cured coating layer can be completely cured. For example, a semi-cured black coating layer (151) and a transparent coating layer (152) can be cured.

A coating film (150) bonded and cured on a substrate assembly (100) like this can be formed into a large-area display device including many unit pixels. In some cases, such a large-area display device can be separated into individual unit modules, as illustrated in FIG. 15.

In this way, when separated into unit modules, a state as illustrated in Fig. 16 can be achieved. The state illustrated in Fig. 16 can be substantially the same as the example illustrated in Fig. 1.

The display device described above is not limited to the configuration and method of the embodiments described above, and the embodiments may be configured by selectively combining all or part of each embodiment so that various modifications can be made.

According to the present disclosure, a display device or display device module equipped with a coating film can be provided.

Claims (15)

wiring board; A first wiring electrode and a second wiring electrode arranged on the above wiring board; A first electrode pad and a second electrode pad connected to the first wiring electrode and the second wiring electrode, respectively; A light emitting element electrically connected to the first electrode pad and the second electrode pad in each of the above unit pixel areas to form a subpixel; and Including a coating film positioned on the light emitting element, The above coating film, A black coating layer positioned on the wiring board and covering at least a portion of a side surface of the light-emitting element; A transparent coating layer positioned on the black coating layer; and An optical layer comprising an optical layer positioned on the transparent coating layer. Display device. In the first paragraph, the optical layer includes an anti-glare pattern. Display device. In the first paragraph, the optical layer includes anti-glare and anti-fingerprint functions. Display device. In the first paragraph, further comprising a support film layer positioned between the transparent coating layer and the optical layer. Display device. In the first paragraph, at least a portion of the coating film is integrated in a semi-cured state. Display device. In the fifth paragraph, the black coating layer and the transparent coating layer are integrated with the support film layer in a semi-cured state. Display device. In the first paragraph, the transparent coating layer and the optical layer are in direct contact. Display device. In the first paragraph, the transparent coating layer includes filler particles. Display device. A method for manufacturing a modular display device, A step of preparing a substrate assembly in which unit light emitting elements are arranged on a wiring board; A step of manufacturing a coating film in which at least a portion is semi-cured; A step of bonding a semi-cured portion of the coating film onto the substrate assembly; and Including the step of separating into individual unit modules. A method for manufacturing a display device. In the 9th paragraph, the coating film, Black coating layer in semi-cured (B-stage) state; A transparent coating layer in a semi-cured (B-stage) state located on the black coating layer; A support film layer positioned on the transparent coating layer; and An optical layer comprising an optical layer positioned on the support film layer. A method for manufacturing a display device. In the 10th paragraph, the step of bonding the coating film onto the substrate assembly is: The black coating layer in the above semi-cured (B-stage) state is bonded to cover at least a portion of the unit light emitting elements on the wiring board. A method for manufacturing a display device. In the 9th paragraph, the step of manufacturing the coating film comprises: A step of forming an optical layer on a support film layer; A step of forming a black coating layer in a semi-cured (B-stage) state on a release film; A step of forming a transparent coating layer in a semi-cured (B-stage) state located on the black coating layer; A step of laminating the support film layer on the transparent coating layer; and A step of removing the above-mentioned heteromorphic film is included. A method for manufacturing a display device. In the 9th paragraph, the bonding step, A step of applying pressure together with heat to the coating film on the substrate assembly. A method for manufacturing a display device. In an integrated coating film bonded to a wiring board on which light sources are arranged, A black coating layer in a semi-cured (B-stage) state located on a release film; A transparent coating layer in a semi-cured (B-stage) state located on the black coating layer; A support film layer positioned on the transparent coating layer; and comprising an optical layer positioned on the above support film layer; Integrated coating film. In the 14th paragraph, the thickness of the black coating layer has a thickness that covers a part of the side of the light source. Integrated coating film.