Resin composition, cured resin product and display device including cured resin product

Abstract

The present disclosure relates to a resin composition, a cured resin product, and a display device including the cured resin product. Resin composition including about 1 to about 10 parts by weight of urethane (meth) acrylate oligomer having two (meth) acrylic groups, about 80 to about 95 parts by weight of monofunctional acrylate monomer, about 0.1 to about 1 part by weight of (meth) having two (meth) acrylic groups an acrylate monomer and about 1 to about 5 parts by weight of a hydrogen abstracting type photoinitiator, where the parts by weight are based on the total weight of the resin composition. Some of the monofunctional acrylate monomers include a dicyclopentenyl group. The resin composition may have a viscosity of greater than or equal to about 5 mPa.s and less than 20 mPa.s at 30 DEG C.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of Korean Patent Application No. 10-2024-0034717 filed in the Korean Intellectual Property Office (KIPO) on March 12, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0003] One or more embodiments relate to a resin composition, a cured resin product, and a display device including the cured resin product. Background Art

[0004] Optically clear adhesives (OCAs) as adhesive sheets have been used as adhesives for display devices. However, as the shapes of display devices diversify, the development of optically clear resins (OCRs) as liquid adhesives is underway. In particular, recently, due to the thinning of display devices, an inkjet process for optically clear resins (OCRs) is needed, and for this purpose, low-viscosity optically clear resins (OCRs) are needed. In the case of light curing of low-viscosity optically clear resins (OCRs), it is desirable to maintain the physical properties of the cured product, such as adhesive properties. Summary of the Invention

[0005] One or more embodiments include a resin composition that ensures a stable inkjet process at room temperature, has high adhesion even after photocuring in an oxygen atmosphere, and is suitable for display devices of various shapes.

[0006] Additional aspects will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the presented embodiments of the disclosure.

[0007] According to one or more embodiments, the resin composition may include:

[0008] about 1 part by weight to about 10 parts by weight of a urethane (meth)acrylate oligomer (A) having two (meth)acrylate groups,

[0009] about 80 parts by weight to about 95 parts by weight of a monofunctional acrylate monomer (B),

[0010] about 0.1 parts by weight to about 1 part by weight of a (meth)acrylate monomer (C) having two (meth)acrylic acid groups, and

[0011] About 1 to about 5 parts by weight of a hydrogen abstraction type photoinitiator (D).

[0012] Some of the monofunctional acrylate monomers (B) may have a dicyclopentenyl group.

[0013] Parts by weight may be based on the total weight of the resin composition.

[0014] The resin composition may have a viscosity at 30° C. of greater than or equal to about 5 mPa·s and less than 20 mPa·s.

[0015] According to embodiments, the urethane (meth)acrylate oligomer having two (meth)acrylic groups may have a weight average molecular weight (Mw) of greater than or equal to about 10,000 and less than 40,000.

[0016] According to an embodiment, the resin composition may include two or more types of urethane (meth)acrylate oligomers having two (meth)acrylic groups.

[0017] According to an embodiment, the molecular weight difference between two or more types of urethane (meth)acrylate oligomers having two (meth)acrylate groups may be in the range of about 5,000 to about 30,000. For example, the molecular weight difference may be a difference in weight average molecular weight.

[0018] According to embodiments, the monofunctional acrylate monomer may have a weight average molecular weight (Mw) of less than or equal to about 500.

[0019] According to an embodiment, the resin composition may include two or more types of monofunctional acrylate monomers.

[0020] According to an embodiment, an amount of the monomer having the dicyclopentenyl group in the monofunctional acrylate monomer may be in a range of about 20 parts by weight to about 40 parts by weight based on the total weight of the resin composition.

[0021] According to embodiments, the (meth)acrylate monomer having two (meth)acrylic acid groups may have a weight average molecular weight (Mw) of less than or equal to about 500.

[0022] According to an embodiment, the resin composition may not include a solvent.

[0023] According to an embodiment, the resin composition may further include about 1 to about 5 parts by weight of a tertiary amine group-containing hydrogen donor.

[0024] According to an embodiment, the urethane (meth)acrylate oligomer having two (meth)acrylate groups may include UV-3700B (Mitsubishi Chemical), UV-3300B (Mitsubishi Chemical), UN-7700 (Negami Industry), UF-C051 (Kyoeisha Chemical), CN9021NS (Sartomer), KRM9465 (Dacelidox), EBECRYL8411 (Dacelidox), or a combination thereof.

[0025] According to an embodiment, the monofunctional acrylate monomer may include isodecyl acrylate, isobornyl acrylate, tetrahydrofuranyl (meth) acrylate, dicyclopentenyloxyethyl acrylate, dicyclopentenyloxyethyl (meth) acrylate, 2-ethylhexyl acrylate, 4-hydroxybutyl acrylate, (2-methyl-2-ethyl-1,3-dioxolan-4-yl) methacrylate, butyl acrylate, lauryl acrylate, diethylene glycol 2-ethylhexyl ether acrylate, mono(2-acryloyloxyethyl) succinate, t-butyl acrylate, n-octyl acrylate, cyclohexyl acrylate, or a combination thereof.

[0026] According to an embodiment, the (meth)acrylate monomer having two (meth)acrylate groups may include 1,9-nonanediol diacrylate, 1,4-butanediol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,8-octanediol di(meth)acrylate, 1,9-octanediol diacrylate, 1,12-dodecanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, dicyclopentane di(meth)acrylate, cyclohexane-1,4-dimethanol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, dicyclopentane dihydroxymethyl di(meth)acrylate, neopentyl glycol-modified trimethylpropane di(meth)acrylate, 1,3-adamantanediol di(meth)acrylate, or a combination thereof.

[0027] According to an embodiment, the storage modulus of a cured resin product generated after photocuring the resin composition at 25° C. may be greater than or equal to about 0.05 MPa and less than 0.5 MPa.

[0028] According to an embodiment, a change in yellowness index (ΔYI) of a cured resin product produced after photocuring of the resin composition may be less than or equal to about 1 before and after a light resistance test based on the DIN 75220 standard.

[0029] According to an embodiment, a laminate obtained by bonding a polyethylene terephthalate (PET) film and soda lime glass using the resin composition may have a 180° peel strength at 25° C. ranging from about 2500 (gf / 25 mm) to about 5000 (gf / 25 mm).

[0030] According to one or more embodiments, there is provided

[0031] A cured resin product that can be produced by photocuring a resin composition.

[0032] The cured resin product may be a bonding member.

[0033] According to one or more embodiments, a display device may include:

[0034] display panel,

[0035] an overlay window disposed on the display panel, and

[0036] A light-curable adhesive layer is disposed between the display panel and the cover window, wherein

[0037] The photocurable adhesive layer may include the above-mentioned cured resin product.

[0038] The display device may be a foldable display device. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The above and other aspects, features and advantages of certain embodiments of the present disclosure will become more apparent from the following description taken in conjunction with the accompanying drawings, in which:

[0040] Figure 1 and Figure 2 is a perspective view schematically showing a portion of a display device according to an embodiment;

[0041] Figure 3A is a schematic cross-sectional view schematically showing a portion of a display device according to an embodiment; and

[0042] Figure 3B 1 is a schematic cross-sectional view schematically showing a portion of a display device according to another embodiment. DETAILED DESCRIPTION

[0043] Because the present disclosure can be modified in various ways and can have various embodiments, specific embodiments will be explained and described in the detailed description. By reference to the embodiments described in detail below, the effects and features of the present disclosure and the methods for implementing the present disclosure will become clear. However, the present disclosure can be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein.

[0044] The terms used herein are for the purpose of describing particular embodiments and are not intended to be limiting. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. Furthermore, when the terms "comprises," "comprising," "includes," and / or "including" are used in this specification, they indicate the presence of the recited features, integers, steps, operations, elements, components, and / or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0045] When an element or layer is referred to as being "on," "connected to," or "coupled to" another element or layer, it can be directly on, directly connected to, or directly coupled to the other element or layer, or intervening elements or layers may be present. However, when an element or layer is referred to as being "directly on," "directly connected to," or "directly coupled to" another element or layer, there are no intervening elements or layers. For purposes of this disclosure, the term "connected" may refer to being physically connected, electrically connected, and / or fluidically connected, with or without intervening elements.

[0046] In this specification, the x-axis, y-axis, and z-axis are not limited to the three axes in the Cartesian coordinate system, but can be interpreted in a broad sense including the three axes in the Cartesian coordinate system. For example, the x-axis, y-axis, and z-axis may refer to axes that are orthogonal to each other, or may refer to axes in different directions that are not orthogonal to each other.

[0047] Spatially relative terms such as "below," "beneath," "beneath," "above," "above," "high," and "side" (e.g., as in "sidewall") may be used herein for descriptive purposes, and thereby, to describe the relationship of one element to another element as illustrated in the accompanying drawings. Spatially relative terms are intended to encompass different orientations of the device in use, operation, and / or manufacture in addition to the orientation depicted in the accompanying drawings. For example, if the device in the drawings were turned over, an element described as "below" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the exemplary term "below" can encompass both the above and below orientations. Furthermore, the device may be oriented in other ways (e.g., rotated 90 degrees or in other orientations), and, as such, the spatially relative descriptors used herein should be interpreted accordingly.

[0048] As used herein, "about" and "approximately" are inclusive of the stated value and mean within an acceptable range of deviation from the particular value as determined by one of ordinary skill in the art taking into account the measurements in question and the errors associated with the measurement of the particular quantity (i.e., the limitations of the measurement system). For example, "about" can mean within one or more standard deviations of the stated value, or within ±30%, ±20%, ±10%, or ±5% of the stated value.

[0049] In the specification and claims, for the purposes of its meaning and interpretation, the phrase "at least one of" is intended to include the meaning of "at least one selected from the following groups." For example, "at least one of A and B" may be understood to mean "A," "B," or "A and B." In the specification and claims, for the purposes of its meaning and interpretation, the term "and / or" is intended to include any combination of the terms "and" and "or." For example, "A and / or B" may be understood to mean "A," "B," or "A and B." The terms "and" and "or" may be used in a conjunctive sense or a disjunctive sense and may be understood to be equivalent to "and / or."

[0050] Unless otherwise defined or implied herein, all terms (including technical and scientific terms) used have the same meaning as commonly understood by those skilled in the art to which the present disclosure belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and should not be interpreted in an ideal or overly formal sense unless clearly defined in the specification.

[0051] The term "(meth)acrylic group" as used herein may be a methacrylic group or an acrylic group. Similarly, the term "(meth)acrylate" as used herein may be a methacrylate or an acrylate.

[0052] The resin composition according to the embodiment may include a urethane (meth)acrylate oligomer having two (meth)acrylate groups (A), a monofunctional acrylate monomer (B), a (meth)acrylate monomer having two (meth)acrylate groups (C), and a hydrogen abstraction type photoinitiator (D).

[0053] In an embodiment, based on 100 parts by weight of the resin composition, the amount of the urethane (meth)acrylate oligomer (A) having two (meth)acrylate groups included may be in the range of about 1 part by weight to about 10 parts by weight, the amount of the monofunctional acrylate monomer (B) included may be in the range of about 80 parts by weight to about 95 parts by weight, the amount of the (meth)acrylate monomer (C) having two (meth)acrylate groups included may be in the range of about 0.1 parts by weight to about 1 part by weight, and the amount of the hydrogen abstraction type photoinitiator (D) included may be in the range of about 1 part by weight to about 5 parts by weight.

[0054] In an embodiment, the urethane (meth) acrylate oligomer (A) having two (meth) acrylic acid groups, the monofunctional acrylate monomer (B), and the (meth) acrylate monomer (C) having two (meth) acrylic acid groups may each independently include two or more types thereof. For example, the urethane (meth) acrylate oligomer (A) having two (meth) acrylic acid groups may include two or three types of urethane (meth) acrylates having two (meth) acrylic acid groups. For example, the monofunctional acrylate monomer (B) may include 2 to 5 types of monofunctional acrylate monomers, or 3 or 4 types of monofunctional acrylate monomers.

[0055] In an embodiment, the weight average molecular weight (Mw) of the urethane (meth) acrylate oligomer (A) having two (meth) acrylic acid groups may be greater than or equal to 10,000 and less than 40,000. For example, the urethane (meth) acrylate oligomer (A) having two (meth) acrylic acid groups may include two types of urethane (meth) acrylate oligomers having two (meth) acrylic acid groups, wherein the molecular weight difference between the two types of urethane (meth) acrylate oligomers having two (meth) acrylic acid groups may be in the range of about 5,000 to about 30,000. For example, the molecular weight difference between the two types of urethane (meth) acrylate oligomers having two (meth) acrylic acid groups may be in the range of about 7,000 to about 25,000. In an embodiment, the monofunctional acrylate monomer (B) may have a weight average molecular weight (Mw) less than or equal to about 500. For example, the monofunctional acrylate monomer (B) may have a weight average molecular weight (Mw) in the range of about 200 to about 500. For example, the monofunctional acrylate monomer (B) may have a weight average molecular weight (Mw) in the range of about 200 to about 400. In an embodiment, the (meth)acrylate monomer (C) having two (meth)acrylate groups may have a weight average molecular weight (Mw) less than or equal to about 500. For example, the (meth)acrylate monomer (C) having two (meth)acrylate groups may have a weight average molecular weight (Mw) in the range of about 100 to about 500. For example, the (meth)acrylate monomer (C) having two (meth)acrylate groups may have a weight average molecular weight (Mw) in the range of about 200 to about 400.

[0056] Some of the monofunctional acrylate monomer (B) may include a dicyclopentenyl group. For example, the monofunctional acrylate monomer (B) may include four types of monofunctional acrylate monomers, and one or two types of monofunctional acrylate monomers may have a dicyclopentenyl group. In an embodiment, based on 100 parts by weight of the resin composition, the amount of the monofunctional acrylate monomer (B) with a dicyclopentenyl group may be in the range of about 20 parts by weight to about 40 parts by weight. When some of the monofunctional acrylate monomer (B) with a dicyclopentenyl group has this amount range, the yellowing of the resin composition under ultraviolet (UV) irradiation and the yellowing of the cured resin product over time due to ultraviolet rays can be prevented or reduced.

[0057] The resin composition may be a solvent-free resin composition containing no solvent.

[0058] The resin composition may have a viscosity of 5 mPa·s or more and less than 20 mPa·s at 30°C. If the viscosity of the resin composition is less than 5 mPa·s, the inkjet discharge amount and the film thickness after application may deviate. If the viscosity of the resin composition is greater than 20 mPa·s, inkjet ejection defects and nozzle clogging may occur.

[0059] In an embodiment, the resin composition may further include about 1 to about 5 parts by weight of a tertiary amine group-containing hydrogen donor (E) based on 100 parts by weight of the resin composition. The tertiary amine group-containing hydrogen donor (E) may promote the initiation of photopolymerization caused by the hydrogen abstraction type photoinitiator (D).

[0060] The urethane (meth) acrylate oligomer (A) having two (meth) acrylic acid groups may be an oligomer containing two (meth) acrylic acid groups each having a urethane bond in one unit. The urethane (meth) acrylate oligomer may include at least one of an acrylate having a urethane bond, a urethane acrylate having a polycarbonate backbone, and a urethane acrylate having a polyether backbone. The urethane (meth) acrylate oligomer (A) having two (meth) acrylic acid groups may include, for example, UV-3700B (Mitsubishi Chemical), UV-3300B (Mitsubishi Chemical), UN-7700 (Negami Industries), UF-C051 (Kyoeisha Chemical), CN9021NS (Sartomer), KRM9465 (Dacelid), EBECRYL8411 (Dacelid), or a combination thereof, but the present disclosure is not limited thereto.

[0061] The monofunctional acrylate monomer (B) may include alicyclic (meth) acrylates, alkyl (meth) acrylates, hydroxyl-containing (meth) acrylates, or combinations thereof. For example, the monofunctional acrylate monomer (B) may include isodecyl acrylate, isobornyl acrylate, tetrahydrofuranyl (meth) acrylate, dicyclopentenyloxyethyl acrylate, dicyclopentenyloxyethyl (meth) acrylate, 2-ethylhexyl acrylate, 4-hydroxybutyl acrylate, (2-methyl-2-ethyl-1,3-dioxolane-4-yl) methacrylate, butyl acrylate, lauryl acrylate, 2-ethylhexyl ether acrylate, diethylene glycol mono(2-acryloyloxyethyl) succinate, tert-butyl acrylate, n-octyl acrylate, cyclohexyl acrylate, or combinations thereof, but the present disclosure is not limited thereto.

[0062] The (meth)acrylate monomer (C) having two (meth)acrylate groups may include 1,9-nonanediol diacrylate, 1,4-butanediol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,8-octanediol di(meth)acrylate, 1,9-octanediol diacrylate, 1,12-dodecanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, dicyclopentane di(meth)acrylate, cyclohexane-1,4-dimethanol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, dicyclopentane dihydroxymethyl di(meth)acrylate, neopentyl glycol-modified trimethylpropane di(meth)acrylate, 1,3-adamantanediol di(meth)acrylate, or a combination thereof, but the present disclosure is not limited thereto.

[0063] The hydrogen abstraction type photoinitiator (D) may include, for example, 1-[4-(4-benzoylphenylthio)phenyl]-2-methyl-2-(4-methylphenylsulfonyl)propan-1-one, benzophenone, benzoylbenzoate, methylbenzoylbenzoate, 4-phenylbenzophenone, hydroxybenzophenone, 3,3'-dimethyl-4-methoxybenzophenone, 2,4,6-trimethylbenzophenone, 4-methylbenzophenone, thioxanthone, 2-Chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, camphorquinone, 3,3',4,4'-tetrakis(tert-butoxycarbonyl)benzophenone, 1-[4-(4-benzoylphenylthio)phenyl]-2-toluenesulfonyl-2-methyl-1-propanone, 2-ethylhexyl 2-([1,1'-biphenyl]-4-ylcarbonyl)benzoate, ketone coumarin, or a combination thereof, but the present disclosure is not limited thereto.

[0064] The tertiary amine group-containing hydrogen donor (E) may include 4-(dimethylamino)-ethyl benzoate, poly(ethylene glycol)bis(p-dimethylaminobenzoate), (methylimino)diethylenebis[4-(dimethylamino)benzoate], 1,4-bis(aminopropyl)piperazine, tetramethylethylenediamine, 4-dimethylaminobenzoic acid-ethylhexyl ester, or a combination thereof, but the present disclosure is not limited thereto.

[0065] In an embodiment, the resin composition may further include additives such as photosensitizers, photopolymerization accelerators, curing catalysts, flame retardants, anti-flow agents, antioxidants, anti-aging agents, ultraviolet absorbers, pigments, dyes, fillers, and diluents in amounts that do not impair the physical properties of the resin composition.

[0066] In an embodiment, the storage modulus of the cured resin product produced after photocuring the resin composition may be greater than or equal to 0.05 MPa and less than 0.5 MPa at 25° C. When the cured resin product has a storage modulus within this range, adhesion and cohesion may be obtained while having excellent adhesive properties.

[0067] In an embodiment, the cured resin product produced after the resin composition is photocured may have a change in the yellowness index (ΔYI) of less than or equal to about 1 before and after a light resistance test based on the DIN 75220 standard. The yellowness index (YI) indicates the degree of separation from white to yellow on the CIE chromaticity diagram. The amount of change in the yellowness index (ΔYI) may be an indicator that can be used to assess the degree of degradation of the cured resin product material due to ultraviolet rays. In the present disclosure, the "amount of change in the yellowness index" may be simply referred to as the "change in the yellowness index".

[0068] The amount of change in the yellowness index (ΔYI) can be expressed by Equation 1.

[0069] [Equation 1]

[0070] ΔYI=YI(after light resistance test)-YI(before light resistance test)

[0071] In an embodiment, a laminate obtained by bonding a polyethylene terephthalate (PET) film to soda-lime glass using the resin composition may have a 180° peel strength at 25°C of greater than or equal to about 2500 (gf / 25mm). For example, the 180° peel strength at 25°C of the laminate may be in the range of about 2500 (gf / 25mm) to about 4000 (gf / 25mm). For example, the 180° peel strength at 25°C of the laminate may be in the range of about 2600 (gf / 25mm) to about 3600 (gf / 25mm).

[0072] The resin composition according to the embodiment can be precisely processed by inkjet printing at room temperature. The resin composition according to the present embodiment can be not significantly affected by oxygen inhibition by oxygen inhibition of polymerization reaction when photocuring in an oxygen atmosphere, so that the resin composition can be easily photocured and can have high light resistance, excellent adhesion and cohesion after photocuring.

[0073] The cured resin product according to the embodiment can be manufactured by irradiating light on the resin composition according to the embodiment under atmospheric conditions. The light irradiation may be, for example, UV irradiation. In an embodiment, the cured resin product may have a storage modulus in the range of about 0.05 MPa to about 0.5 MPa at 25 ° C. In an embodiment, the amount of change (ΔYI) of the yellowness index of the cured resin product before and after the light resistance test based on the DIN75220 standard may be less than or equal to about 1. The 180 ° peel strength of a laminate manufactured by applying a resin composition between a polyethylene terephthalate (PET) film and soda-lime glass and irradiating light thereon at 25 ° C may be, for example, in the range of about 2500 (gf / 25mm) to about 4000 (gf / 25mm). For example, a laminate manufactured by applying the resin composition between a polyethylene terephthalate (PET) film and soda-lime glass and irradiating light thereon may have a 180° peel strength at 25° C. in the range of, for example, about 2600 (gf / 25mm) to about 3600 (gf / 25mm).

[0074] In an embodiment, the cured resin product may be an adhesive member, and the adhesive member may be applied to a display device.

[0075] The display device according to the embodiment may include a display panel, a cover window provided on the display panel, and a photocurable adhesive layer provided between the display panel and the cover window. The photocurable adhesive layer may include the curable resin product according to the embodiment.

[0076] The display device according to the embodiment may be a foldable display device. The display device according to the embodiment may be a display device including a bending region. The display device according to the embodiment may be a rollable display device. The display device according to the embodiment may be a display device having a curved surface in some regions.

[0077] The resin composition according to the embodiment may be applied to display devices having various shapes such as folding, bending, curling, and curving by a method such as inkjet printing to stably bond members such as a display panel and a cover window to each other.

[0078] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The same or corresponding components will be denoted by the same reference numerals, and thus redundant descriptions thereof will be omitted.

[0079] Figure 1 and Figure 2 1 is a perspective view schematically showing a portion of a display device 1 according to an embodiment. Figure 1 The display device 1 is shown in an unfolded state, and Figure 2 The display device 1 is shown in a folded state.

[0080] refer to Figure 1 and Figure 2 , the display device 1 may include a lower cover LC, a display panel DP, and a cover window CW.

[0081] The lower cover LC may include a first portion P1 and a second portion P2, each supporting the display panel DP. The lower cover LC may be foldable about a folding axis FAX defined between the first portion P1 and the second portion P2. In an embodiment, the lower cover LC may further include a hinge portion HP, and the hinge portion HP may be provided between the first portion P1 and the second portion P2.

[0082] The display panel DP may include a display area DA. The display panel DP may provide an image through an array of a plurality of pixels PX arranged in the display area DA. Each of the pixels PX may be defined as a light-emitting region where light is emitted by a light-emitting element electrically connected to a pixel circuit. In an embodiment, each of the pixels PX may emit red, green, or blue light. In another embodiment, each of the pixels PX may emit red, green, blue, or white light.

[0083] The light-emitting elements included in the display panel DP may include organic light-emitting diodes, inorganic light-emitting diodes, micro light-emitting diodes, and / or quantum dot light-emitting diodes. For ease of explanation, the following description will focus on an embodiment in which the light-emitting elements provided by the display panel DP include organic light-emitting diodes, but the present disclosure is not limited thereto and may be applied even to embodiments including other light-emitting elements.

[0084] The display area DA may include a first display area DA1 and a second display area DA2 arranged on opposite sides around a folding axis FAX passing through the display area DA. The first display area DA1 and the second display area DA2 may be located on the first portion P1 and the second portion P2 of the lower cover LC, respectively. The display panel DP may provide first and second images using light emitted from pixels PX disposed in the first and second display areas DA1 and DA2. In embodiments, the first and second images may be part of an image provided by the display area DA of the display panel DP. In another embodiment, the display panel DP may provide the first and second images independently of each other.

[0085] The display panel DP may be foldable about a folding axis FAX. In a case where the display panel DP is folded, the first display area DA1 and the second display area DA2 of the display panel DP may face each other.

[0086] Figure 1 and Figure 2 In the embodiment shown, the folding axis FAX extends in the y direction, but the present disclosure is not limited thereto. In an embodiment, the folding axis FAX may extend in the x direction intersecting the y direction. In some embodiments, the folding axis FAX on the xy plane may extend in a direction intersecting the x direction and the y direction.

[0087] Figure 1 and Figure 2 An embodiment in which there is only one folding axis FAX is shown, but the present disclosure is not limited thereto. In an embodiment, the display panel DP may be folded multiple times around a plurality of folding axes FAX passing through the display area DA.

[0088] A cover window CW may be provided on the display panel DP to cover the display panel DP. The cover window CW may be foldable or bendable to prevent cracks caused by external forces. When the display panel DP is folded about the folding axis FAX, the cover window CW may also be folded together.

[0089] Figure 3A is a schematic cross-sectional view schematically showing a portion of a display device 2 according to an embodiment, and Figure 3B Schematic cross-sectional view schematically shows a part of a display device 3 according to another embodiment. Figure 3A and Figure 3B Corresponding to along Figure 1 1-1' is a cross-sectional view of the display device taken along line II'.

[0090] refer to Figure 3A and Figure 3B The display panel DP may have a stacked structure including a substrate 10 , a pixel circuit layer PCL, a display element layer DEL, a thin film encapsulation layer TFE, a touch electrode layer TEL, and an optical function layer OFL.

[0091] The substrate 10 may include glass or a polymer resin. In an embodiment, the polymer resin may include at least one of polyethersulfone, polyarylate, polyetherimide, polyethylene naphthalate, polyethylene terephthalate, polyphenylene sulfide, polyimide, polycarbonate, cellulose triacetate, and cellulose acetate propionate.

[0092] The pixel circuit layer PCL may be disposed on the substrate 10. Figure 3A and Figure 3BThe pixel circuit layer PCL may include a thin film transistor TFT, and a buffer layer 11, a first insulating layer 13a, a second insulating layer 13b, a third insulating layer 15 and a planarization layer 17 disposed below or / and above components of the thin film transistor TFT.

[0093] The buffer layer 11 can reduce or block the penetration of external foreign matter, moisture, or external air from the lower portion of the substrate 10, and provide a flat surface on the substrate 10. The buffer layer 11 may include an inorganic insulating material such as silicon nitride, silicon oxynitride, and silicon oxide, and may be a single layer or multiple layers containing the inorganic insulating material.

[0094] The thin film transistor (TFT) on the buffer layer 11 may include a semiconductor layer 12, which may include polycrystalline silicon. In some embodiments, the semiconductor layer 12 may include amorphous silicon, an oxide semiconductor, an organic semiconductor, or the like. The semiconductor layer 12 may include a channel region 12c and a drain region 12a and a source region 12b, respectively disposed on opposite sides of the channel region 12c. The gate electrode 14 may overlap the channel region 12c in a plan view.

[0095] The gate electrode 14 may include a low-resistance metal material, a conductive material such as molybdenum (Mo), aluminum (Al), copper (Cu), titanium (Ti), etc., and may be formed as a multilayer or single layer containing at least one of the above conductive materials.

[0096] The first insulating layer 13a may be located between the semiconductor layer 12 and the gate electrode 14. The first insulating layer 13a may include an inorganic insulating material such as silicon oxide (SiO2), silicon nitride (SiN X ), silicon oxynitride (SiON), aluminum oxide (Al2O3), titanium oxide (TiO2), tantalum oxide (Ta2O5), hafnium oxide (HfO2) or zinc oxide (ZnO X ). Zinc oxide may include ZnO and ZnO2.

[0097] The second insulating layer 13b may cover the gate electrode 14. The second insulating layer 13b may include an inorganic insulating material such as silicon oxide (SiO2), silicon nitride (SiN X ), silicon oxynitride (SiON), aluminum oxide (Al2O3), titanium oxide (TiO2), tantalum oxide (Ta2O5), hafnium oxide (HfO2) or zinc oxide (ZnO X ).

[0098] The upper electrode Cst2 of the storage capacitor Cst may be disposed on the second insulating layer 13b. The upper electrode Cst2 may at least partially overlap with the gate electrode 14 disposed below the upper electrode Cst2 in a plan view. The overlapping gate electrode 14 and the upper electrode Cst2, with the second insulating layer 13b therebetween, may form the storage capacitor Cst. For example, the gate electrode 14 may function as the lower electrode Cst1 of the storage capacitor Cst.

[0099] In an embodiment, the storage capacitor Cst and the thin film transistor TFT may overlap each other in a plan view. In another embodiment, the storage capacitor Cst may not overlap with the thin film transistor TFT. For example, the lower electrode Cst1 of the storage capacitor Cst may be formed as a separate component relative to the gate electrode 14 so as to be spaced apart from the gate electrode 14 in a plan view.

[0100] The upper electrode Cst2 may include aluminum (Al), platinum (Pt), palladium (Pd), silver (Ag), magnesium (Mg), gold (Au), nickel (Ni), neodymium (Nd), iridium (Ir), chromium (Cr), calcium (Ca), molybdenum (Mo), titanium (Ti), tungsten (W) and / or copper (Cu), and may be a single layer or a multilayer including at least one of these materials.

[0101] The third insulating layer 15 may cover the upper electrode Cst2. The third insulating layer 15 may include an inorganic insulating material such as silicon oxide (SiO2), silicon nitride (SiN X ), silicon oxynitride (SiON), aluminum oxide (Al2O3), titanium oxide (TiO2), tantalum oxide (Ta2O5), hafnium oxide (HfO2) or zinc oxide (ZnO X ). The third insulating layer 15 may be a single layer or multiple layers including at least one of these inorganic insulating materials.

[0102] The drain electrode 16a and the source electrode 16b may each be located on the third insulating layer 15. The drain electrode 16a and the source electrode 16b may be connected to the drain region 12a and the source region 12b respectively through contact holes in the insulating layer below the drain electrode 16a and the source electrode 16b. The drain electrode 16a and the source electrode 16b may include a material with good electrical conductivity. The drain electrode 16a and the source electrode 16b may include a conductive material such as molybdenum (Mo), aluminum (Al), copper (Cu), titanium (Ti), etc., and may be formed into a multilayer or single layer including at least one of these materials. In an embodiment, the drain electrode 16a and the source electrode 16b may each have a multilayer structure of Ti / Al / Ti.

[0103] The planarization layer 17 may include an organic insulating material, such as a general polymer (such as polymethyl methacrylate (PMMA) or polystyrene (PS)), or a polymer derivative having a phenol group, an acrylic polymer, an imide polymer, an aromatic ether polymer, an amide polymer, a fluorine polymer, a paraxylene polymer, a vinyl alcohol polymer and a blend thereof.

[0104] The display element layer DEL may be provided on the pixel circuit layer PCL having the above-described structure. The display element layer DEL may include an organic light-emitting diode OLED as a light-emitting device, and the organic light-emitting diode OLED may have a stacked structure of a first electrode 21, an emission layer 22, and a second electrode 23. The first electrode 21 of the organic light-emitting diode OLED may be electrically connected to the thin film transistor TFT through a contact hole defined in the planarization layer 17.

[0105] The first electrode 21 may include a conductive oxide such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium oxide (In2O3), indium gallium oxide (IGO), or aluminum zinc oxide (AZO). In an embodiment, the first electrode 21 may include a reflective film including silver (Ag), magnesium (Mg), aluminum (Al), platinum (Pt), palladium (Pd), gold (Au), nickel (Ni), neodymium (Nd), iridium (Ir), chromium (Cr), or compounds thereof. In some embodiments, the first electrode 21 may further include a film including ITO, IZO, ZnO, or In2O3 above or below the reflective film.

[0106] A pixel defining layer 19 having an opening 19OP exposing at least a portion of the first electrode 21 may be disposed on the first electrode 21. The pixel defining layer 19 may include an organic insulating material and / or an inorganic insulating material. The opening 19OP may define a light-emitting region of light emitted from the organic light-emitting diode OLED. For example, the size (e.g., width) of the opening 19OP may correspond to the size (e.g., width) of the light-emitting region in a plan view. Accordingly, the size (e.g., width) of the pixel PX may depend on the size (e.g., width) of the opening 19OP of the pixel defining layer 19.

[0107] The emission layer 22 may be disposed in the opening 19OP of the pixel defining layer 19. The emission layer 22 may include a polymer organic material or a low-molecular organic material that emits light of a certain color. In some embodiments, the emission layer 22 may include an inorganic light-emitting material or quantum dots.

[0108] Despite Figure 3A and Figure 3BAlthough not shown in the figure, the first functional layer and the second functional layer may be respectively disposed below and above the emission layer 22. For example, the first functional layer may include a hole transport layer (HTL), or an HTL and a hole injection layer (HIL). The second functional layer may include an electron transport layer (ETL) and / or an electron injection layer (EIL). However, the present disclosure is not limited thereto. The first functional layer and the second functional layer may be selectively disposed above and below the emission layer 22, respectively.

[0109] Similar to the second electrode 23 to be described below, the first functional layer and the second functional layer may each be formed as a common layer that completely covers the substrate 10 .

[0110] The second electrode 23 may be disposed on the first electrode 21 and may overlap with the first electrode 21 in a plan view. The second electrode 23 may include a conductive material having a low work function. For example, the second electrode 23 may include a (semi) transparent layer comprising silver (Ag), magnesium (Mg), aluminum (Al), platinum (Pt), palladium (Pd), gold (Au), nickel (Ni), neodymium (Nd), iridium (Ir), chromium (Cr), lithium (Li), calcium (Ca), or an alloy thereof. In some embodiments, the second electrode 23 may further include a layer comprising ITO, IZO, ZnO, or In2O3 on the (semi) transparent layer comprising these materials. The second electrode 23 may be formed as a whole to completely cover the substrate 10.

[0111] The encapsulation member may be provided on the display element layer DEL. In an embodiment, the encapsulation member may be provided as a thin film encapsulation layer TFE. The thin film encapsulation layer TFE may be provided on and cover the display element layer DEL. The thin film encapsulation layer TFE may include at least one inorganic encapsulation layer and at least one organic encapsulation layer. In an embodiment, the thin film encapsulation layer TFE may include a first inorganic encapsulation layer 31, an organic encapsulation layer 32, and a second inorganic encapsulation layer 33 stacked in sequence. In another embodiment, the encapsulation member may be provided as an encapsulation substrate.

[0112] The first inorganic encapsulation layer 31 and the second inorganic encapsulation layer 33 may each include at least one inorganic material, such as at least one of aluminum oxide, titanium oxide, tantalum oxide, hafnium oxide, zinc oxide, silicon oxide, silicon nitride, and silicon oxynitride. The organic encapsulation layer 32 may include a polymer material. The polymer material may include at least one of acrylic resin, epoxy resin, polyimide, and polyethylene. In an embodiment, the organic encapsulation layer 32 may include acrylate. The organic encapsulation layer 32 may be formed by curing a monomer or applying a polymer.

[0113] A touch electrode layer TEL including touch electrodes may be provided on the thin film encapsulation layer TFE, and an optical function layer OFL may be provided on the touch electrode layer TEL. The touch electrode layer TEL may obtain coordinate information based on external input (e.g., a touch event). The optical function layer OFL may reduce the reflectivity of light (external light) incident from the outside on display devices 1, 2, and 3, and improve the color purity of light emitted from display devices 1, 2, and 3.

[0114] In embodiments, the optical functional layer OFL may include a phase retarder and / or a polarizer. The phase retarder may be a film type or a liquid crystal coating type, and may include a λ / 2 phase retarder and / or a λ / 4 phase retarder. The polarizer may also be a film type or a liquid crystal coating type. A film type polarizer may include a stretched synthetic resin film, and a liquid crystal coating type polarizer may include liquid crystals arranged in an array. The phase retarder and polarizer may further include a protective film.

[0115] In an embodiment, the optical function layer OFL may include a destructive interference structure. The destructive interference structure may include a first reflective layer and a second reflective layer disposed on different layers. The first reflected light and the second reflected light reflected from the first reflective layer and the second reflective layer, respectively, may destructively interfere with each other, thereby reducing external light reflectivity.

[0116] The adhesive member may be disposed between the touch electrode layer TEL and the optical function layer OFL. The adhesive member may be a photocurable adhesive layer (not shown) including a resin composition.

[0117] The cover window CW may be placed on the display panel DP. The cover window CW may be adhered to the display panel DP using an adhesive member. The adhesive member may be a photocurable adhesive layer (not shown) including the resin composition described above.

[0118] The cover window CW may have high transmittance to transmit light emitted from the display panel DP. In an embodiment, the cover window CW may have a transmittance greater than or equal to about 85% and a transmission haze less than or equal to about 2%, but the present disclosure is not limited thereto.

[0119] The cover window CW may have a small thickness to minimize the weight of the display devices 1 , 2 , and 3 , and may have high strength and hardness to protect the display panel DP from external impact.

[0120] The optical function layer OFL may be interposed between the cover window CW and the touch electrode layer TEL, and an adhesive member may be provided between the optical function layer OFL and the cover window CW. The adhesive member may be a photocurable adhesive layer OCRL including the resin composition as described above.

[0121] In an embodiment, Figure 3B As shown in , the protective layer PL may be provided on the cover window CW. The protective layer PL may cover the cover window CW and may protect the cover window CW. The protective layer PL may include at least one transparent synthetic resin, such as at least one of polyethylene terephthalate (PET), polypropylene (PP), polystyrene (PP) and polyimide (PI), and may include a hard coating layer. In an embodiment, an adhesive member (such as a photocurable adhesive layer (not shown) including a resin composition) may be provided between the protective layer PL and the cover window CW. In another embodiment, as Figure 3A As shown in FIG, the protection layer PL may be omitted, and the outermost surfaces of the display device 1 and the display device 2 may be provided as a cover window CW to improve the glass texture.

[0122] [Example]

[0123] Preparation of resin composition

[0124] The resin compositions of Examples 1 to 5 and Comparative Examples 1 to 5 were prepared according to the composition ratios shown in Table 1 and Table 2, respectively. The composition ratio of each material refers to the weight parts based on the total weight (100 parts by weight) of the resin composition. The urethane acrylate oligomer in Table 1 and Table 2 refers to a urethane (meth) acrylate oligomer having two (meth) acrylic acid groups. The multifunctional acrylic monomer in Table 1 and Table 2 refers to a (meth) acrylate monomer having two (meth) acrylic acid groups.

[0125] Each material listed in Table 1 and Table 2 was stirred in a light-shielding container at room temperature at 1000 rpm for 30 minutes by using a planetary centrifugal mixer (Shashin Chemical Co., Ltd.) to obtain resin compositions of Examples 1 to 5 and Comparative Examples 1 to 5.

[0126] [Table 1]

[0127]

[0128] [Table 2]

[0129]

[0130]

[0131] Information on materials used to prepare the resin composition

[0132] [Urethane acrylate oligomer]

[0133] UV-3700B: Urethane acrylate (Mitsubishi Chemical Corporation)

[0134] UV-3300B: Urethane acrylate (Mitsubishi Chemical Corporation)

[0135] UN-7700: Urethane acrylate (Negami Industry Co., Ltd.)

[0136] [Multifunctional acrylic monomer]

[0137] Viscoat #260: 1,9-nonanediol diacrylate (Osaka Organic Chemical Industry Co., Ltd.)

[0138] [Monofunctional acrylic monomer]

[0139] IDAA: Isodecyl acrylate (Osaka Organic Chemical Industry Co., Ltd.) (CAS No. 1330-61-6)

[0140] IBXA: Isobornyl acrylate (Osaka Organic Chemical Industry Co., Ltd.) (CAS No. 5888-33-5)

[0141] FA-512AS: Dicyclopentenyloxyethyl acrylate (Resonac Co., Ltd.)

[0142] FA-512M: Dicyclopentenyloxyethyl (meth)acrylate (Resonac Co., Ltd.)

[0143] FA-513AS: Dicyclopentane acrylate (Resonac Co., Ltd.)

[0144] THF-A: Tetrahydrofuryl acrylate (Kyoeisha Chemical Co., Ltd.)

[0145] [Hydrogen abstraction photoinitiator]

[0146] ESACURE 1001M: 1-[4-(4-Benzoylphenylsulfanyl)phenyl]-2-methyl-2-(4-methylphenylsulfonyl)propan-1-one (IGM Resins Co., Ltd.)

[0147] [Intramolecular ring-opening photoradical polymerization initiator]

[0148] Omnirad 819: Phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (IGM Resins Ltd.)

[0149] [Hydrogen donor containing tertiary amine group]

[0150] Omnirad EDB: ethyl 4-(dimethylamino)benzoate (IGM resin)

[0151] Omnirad EHA: 4-Dimethylaminobenzoic acid ethylhexyl ester (IGM resin)

[0152] Physical property evaluation

[0153] Physical properties of the resin compositions of Examples 1 to 5 and Comparative Examples 1 to 5 were evaluated in the following manner. The results are shown in Tables 3 and 4 below, respectively.

[0154] [Viscosity measurement]

[0155] The viscosity of each of the resin compositions was measured using a viscometer (TVE-25L: Toki Sangyo) at 30° C. and at a speed of 50 rpm based on the JISK 2283 testing method.

[0156] [Inkjet Printer Application Characteristics]

[0157] Each of the resin compositions was applied to a slide glass using an inkjet printer from MICROJET Co., Ltd. at a head temperature of 30° C. and ultraviolet (UV) cured. The appearance of the coating film was evaluated after curing. The evaluation results are shown below.

[0158] ◎: Suitable for application without thickness variation in the film

[0159] ×: Cannot be sprayed

[0160] [Measurement of storage modulus of cured materials]

[0161] A release-treated PET film (NP100A, Vanac Co., Ltd.) and a silicone rubber sheet with 8 mm diameter holes (Yaiga Plastics Co., Ltd.) were sequentially laminated on a glass slide (Matsunami Glass Co., Ltd., S1112), and 28 μL of the resin composition was dropped into the holes of the silicone rubber sheet. In this regard, ultraviolet light was irradiated using a UV LED lamp having emission peaks at 405 nm and 365 nm so that the total amount (cumulative amount) of light was 4000 mJ / cm 2 , to obtain a cured resin product sample having a diameter of 8 mm and a thickness of 500 μm. For the obtained cured resin product sample, the storage modulus was measured using a dynamic viscoelasticity measuring device (Antonpa, MCR302) at 25° C., a frequency of 1 Hz, a temperature range of −50° C. to 80° C., and a heating rate of 2° C. / min.

[0162] [Appearance after curing material bonding]

[0163] The resin composition was applied to a slide glass (S1112, Matsunami Glass Co., Ltd.) using an inkjet printer to a thickness of 200 μm. In this regard, ultraviolet rays were irradiated using a UV LED lamp having emission peaks at 405 nm and 365 nm so that the total amount of light was 4000 mJ / cm 2 , and a cured resin product layer was formed on a glass slide. A PET film (Toyobo Co., Ltd., product name A4360, 50 μm thickness) was attached to the cured resin product layer and treated at 30 ° C and 0.5 MPa for 5 minutes by using an automatic heating and pressing device (Chiyoda Electronics Co., Ltd., product name ACS-230). As a result, a laminate consisting of a glass slide, a cured material layer and a PET film was obtained. The appearance of the obtained laminate was evaluated. The evaluation results are shown below.

[0164] ◎: No leakage of unreacted material or unbonded parts.

[0165] Leakage of unreacted material: Leakage of uncured, unreacted material.

[0166] Poor adhesion: There were areas where the glass slide did not adhere to the PET film.

[0167] [Light resistance test]

[0168] The laminated panels manufactured as described above were subjected to a light resistance test to confirm the appearance of the cured product after bonding. 2 The light resistance test was conducted by irradiating ultraviolet rays having a wavelength of 280 nm to 300 nm for 80 hours.

[0169] Before and after the light resistance test, the yellowness index (YI) of the laminate was measured by using a spectrocolorimeter COH 7700 (Nippon Denshoku), and the corresponding ΔYI was calculated according to the following Equation 1.

[0170] [Equation 1]

[0171] ΔYI=YI(after test)-YI(before test)

[0172] [180° peel strength]

[0173] In order to confirm the 180° peel strength after bonding the cured product, the laminated board manufactured as described above was tested for 180° peel strength by using a tensile tester (INSTRON 5965). The 180° peel strength test was performed at 25°C and a tensile speed of 300 mm / min.

[0174] [Table 3]

[0175] Material Example 1 Example 2 Example 3 Example 4 Example 5 Viscosity [mPa·s] (30°C) 19.8 5.1 12.7 10.8 9.7 Inkjet printer application (30℃) ◎ ◎ ◎ ◎ ◎ Storage modulus [MPa] (25℃) 0.132 0.487 0.395 0.228 0.052 Appearance after bonding ◎ ◎ ◎ ◎ ◎ ΔYI before and after light fastness test 0.78 0.35 0.63 0.48 0.95 180° peel strength [gf / 25mm] (25℃) 2780 3570 3250 2940 2600

[0176] [Table 4]

[0177]

[0178] Referring to Table 3, each of the resin compositions of Examples 1 to 5 had a viscosity at 30° C. ranging from about 5 mPa·s to about 20 mPa·s, such that the resin composition could be applied to a uniform thickness at 30° C. using an inkjet printer.

[0179] Each of the cured resin products obtained by curing the resin compositions of Examples 1 to 5 had a storage modulus at 25°C ranging from about 0.05 MPa to about 0.5 MPa, indicating that the cured resin products had suitable adhesiveness and cohesion at room temperature. The 180° peel strength of the adhesive used for bonding a glass slide to a PET film exhibited a high value exceeding 2500 [gf / 25mm].

[0180] The cured resin products obtained by curing the resin compositions of Examples 1 to 5 all had small ΔYI values ​​of less than 1 before and after the light resistance test, showing little yellowing.

[0181] Compared with Examples 1 to 5, Comparative Example 1 has a high content of urethane acrylate oligomers, Comparative Example 2 has a high content of multifunctional acrylic monomers, Comparative Example 3 uses a dicyclopentanyl group instead of a dicyclopentenyl group in the monofunctional acrylate monomer, Comparative Example 4 does not use a tertiary amine-containing hydrogen donor, and Comparative Example 5 uses an intramolecular ring-opening photopolymerization initiator instead of a hydrogen abstraction photoinitiator.

[0182] Referring to Table 4, the resin composition of Comparative Example 1 had a high viscosity, and it was difficult to eject the resin composition of Comparative Example 1 from an inkjet printer at 30°C.

[0183] The cured resin product obtained by curing the resin composition of Comparative Example 2 had a high storage modulus at 25°C, and adhesion defects occurred in the laminate. As a result, adhesion to the slide glass and PET film decreased, and the 180°C peel strength of the laminate decreased.

[0184] The cured resin product obtained by curing the resin composition of Comparative Example 3 had a large ΔYI before and after the light resistance test, and yellowing occurred after the test.

[0185] The cured resin product obtained by curing the resin composition of Comparative Example 4 had a low storage modulus at 25°C. For this reason, when the slide glass and the FET film were bonded together, unreacted material in the cured resin product overflowed to the outside. The cohesion of the cured product was reduced, and the 180° peel strength was greatly reduced.

[0186] The cured resin product obtained by curing the resin composition of Comparative Example 5 was significantly affected by oxygen inhibition, resulting in an increased amount of unreacted material. Consequently, unreacted material in the cured resin product overflowed when the glass slide and FET film were bonded. Due to poor surface curing of the adhesive, the 180° peel strength was significantly reduced.

[0187] The resin composition according to the embodiment ensures a stable inkjet process at room temperature, has high adhesive strength even after photocuring in an oxygen atmosphere, can prevent or reduce yellowing, and is suitable for display devices of various shapes.

[0188] The above description is an example of the technical features of the present disclosure, and those skilled in the art will be able to make various modifications and variations. Therefore, the above embodiments of the present disclosure can be implemented separately or in combination with each other.

[0189] Therefore, the embodiments disclosed in this disclosure are not intended to limit the technical spirit of this disclosure, but to describe the technical spirit of this disclosure, and the scope of the technical spirit of this disclosure is not limited by these embodiments. The scope of protection of this disclosure should be interpreted by the claims, and should be interpreted as all technical spirits within the scope of equivalents are included in the scope of this disclosure.

Claims

1. A resin composition comprising: 1 to 10 parts by weight of a urethane (meth)acrylate oligomer having two (meth)acrylate groups; 80 to 95 parts by weight of a monofunctional acrylate monomer; 0.1 to 1 parts by weight of a (meth)acrylate monomer having two (meth)acrylic acid groups; and 1 to 5 parts by weight of a hydrogen abstraction photoinitiator, wherein Some of the monofunctional acrylate monomers include dicyclopentenyl, The parts by weight are based on the total weight of the resin composition, and The resin composition has a viscosity at 30° C. of greater than or equal to 5 mPa·s and less than 20 mPa·s. 2 . The resin composition according to claim 1 , wherein the urethane (meth)acrylate oligomer having two (meth)acrylic groups has a weight average molecular weight greater than or equal to 10,000 and less than 40,000. 3 . The resin composition according to claim 1 , wherein the resin composition comprises two or more types of the urethane (meth)acrylate oligomer having two (meth)acrylic groups. 4 . The resin composition according to claim 3 , wherein a difference in molecular weight between the two or more types of urethane (meth)acrylate oligomers having two (meth)acrylic groups is in the range of 5,000 to 30,000. The resin composition according to claim 1 , wherein the weight average molecular weight of the monofunctional acrylate monomer is less than or equal to 500. The resin composition according to claim 1 , wherein the resin composition comprises two or more types of the monofunctional acrylate monomers. 7 . The resin composition according to claim 1 , wherein an amount of the monomer having the dicyclopentenyl group in the monofunctional acrylate monomer is in a range of 20 parts by weight to 40 parts by weight based on the total weight of the resin composition. 8 . The resin composition according to claim 1 , wherein the (meth)acrylate monomer having two (meth)acrylic acid groups has a weight average molecular weight of less than or equal to 500. 9 . The resin composition according to claim 1 , wherein the resin composition does not include a solvent.

10. The resin composition according to claim 1, further comprising: 1 to 5 parts by weight of a tertiary amine group-containing hydrogen donor.

11. The resin composition according to claim 1, wherein the urethane (meth)acrylate oligomer having two (meth)acrylic groups comprises Mitsubishi Chemical's UV-3700B, Mitsubishi Chemical's UV-3300B, Negami Industry's UN-7700, Kyoeisha Chemical's UF-C051, Sartomer's CN9021NS, Daicel's KRM9465, Daicel's EBECRYL8411, or a combination thereof.

12. The resin composition according to claim 1, wherein the monofunctional acrylate monomer comprises isodecyl acrylate, isobornyl acrylate, tetrahydrofuranyl (meth) acrylate, dicyclopentenyloxyethyl acrylate, dicyclopentenyloxyethyl (meth) acrylate, 2-ethylhexyl acrylate, 4-hydroxybutyl acrylate, (2-methyl-2-ethyl-1,3-dioxolan-4-yl) methacrylate, butyl acrylate, lauryl acrylate, diethylene glycol 2-ethylhexyl ether acrylate, mono(2-acryloyloxyethyl) succinate, t-butyl acrylate, n-octyl acrylate, cyclohexyl acrylate, or a combination thereof.

13. The resin composition according to claim 1, wherein the (meth)acrylate monomer having two (meth)acrylate groups comprises 1,9-nonanediol diacrylate, 1,4-butanediol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,8-octanediol di(meth)acrylate, 1,9-octanediol diacrylate, 1,12-dodecanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, dicyclopentane di(meth)acrylate, cyclohexane-1,4-dimethanol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, dicyclopentane dihydroxymethyl di(meth)acrylate, neopentyl glycol-modified trimethylpropane di(meth)acrylate, 1,3-adamantanediol di(meth)acrylate, or a combination thereof. The resin composition according to claim 1 , wherein a cured resin product produced by photocuring the resin composition has a storage modulus at 25° C. greater than or equal to 0.05 MPa and less than 0.5 MPa. The resin composition according to claim 1 , wherein a change in yellowness index ΔYI of a cured resin product produced after photocuring of the resin composition is less than or equal to 1 before and after a light resistance test based on the DIN 75220 standard. 16 . The resin composition according to claim 1 , wherein a laminate obtained by bonding a polyethylene terephthalate film and soda lime glass using the resin composition has a 180° peel strength at 25° C. ranging from 2500 gf / 25 mm to 5000 gf / 25 mm. 17 . A cured resin product produced by photocuring the resin composition according to claim 1 . 18 . The cured resin product according to claim 17 , wherein the cured resin product is an adhesive member.

19. A display device comprising: Display panel; A cover window disposed on the display panel; and A photocurable adhesive layer is disposed between the display panel and the cover window, wherein The photocurable adhesive layer includes the cured resin product according to claim 17 or 18.

20. The display device according to claim 19, wherein the display device is a foldable display device.

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