Resin composition, adhesive member, and display device including adhesive member

Abstract

To provide a resin composition which exhibits low viscosity characteristics before curing, and exhibits low elastic modulus and high adhesive force after curing, an adhesive member formed of the resin composition, and a display device including the adhesive member.SOLUTION: A resin composition in one embodiment may contain at least one monofunctional (meth)acrylate monomer, an urethane (meth)acrylate oligomer having a weight average molecular weight of 5,000 or more and 100,000 or less, a dendritic polymer, and at least one photoinitiator including a radical polymerization initiator. Thus, the resin composition may exhibit excellent low viscosity characteristics before curing, and may exhibit excellent flexibility and excellent adhesive reliability after curing.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a resin composition containing a dendritic polymer, an adhesive member made of the resin composition, and a display device including the adhesive member. [Background technology]

[0002] Various display devices have been developed for use in multimedia devices such as televisions, mobile phones, tablet computers, navigation systems, game consoles, etc. In particular, recently, development has been underway regarding display devices that can be folded, bent, or rolled up using flexible display members to facilitate portability and improve user convenience. Adhesive resins used to form adhesive layers applied to display devices of various shapes are required to have excellent coating properties with respect to display device members of various shapes. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] U.S. Patent Application Publication No. 2022 / 0380611 [Patent Document 2] Korean Patent Registration No. 10-1740056 [Patent Document 3] Chinese Patent Application Publication No. 115537167 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present invention is to provide a resin composition that exhibits low viscosity characteristics before curing and a low elastic modulus and high adhesive strength after curing, an adhesive member made of the resin composition, and a display device that includes the adhesive member. [Means for solving the problem]

[0005] One embodiment provides a resin composition including at least one monofunctional (meth)acrylate monomer, a urethane (meth)acrylate oligomer having a weight average molecular weight of 5,000 or more and 100,000 or less, a dendritic polymer, and at least one photoinitiator including a radical polymerization initiator.

[0006] The weight of the dendritic polymer may be 0.5 wt % or more and 15 wt % or less based on the total weight of the resin composition.

[0007] The glass transition temperature of the dendritic polymer may be 25°C or higher and 180°C or lower.

[0008] The weight average molecular weight of the dendritic polymer may be 1,000 or more and 50,000 or less.

[0009] The dendritic polymer may include a repeating unit represented by the following formula 1: [ka] chemical formula 1 In Chemical Formula 1, R1 may be a hydrogen atom or a methyl group, and R2 may be an alkyl group having 1 to 20 carbon atoms.

[0010] The dendritic polymer may contain multifunctional thiol residues.

[0011] The dendritic polymer may have a molecular weight distribution of 1.0 or more and 3.0 or less.

[0012] The resin composition may be solvent-free.

[0013] The resin composition may have a shear viscosity of 5 mPa·s or more and 50 mPa·s or less at 25° C. as measured by JIS Z8803 method.

[0014] After photocuring, the resin composition may have a storage modulus of 1 MPa or less at a frequency of 1 Hz and a temperature of -20°C.

[0015] After photocuring, the resin composition may have a 180° peel strength of 800 gf / 25 mm or more at a temperature of 25° C. from at least one of a glass substrate and a polymer substrate.

[0016] The resin composition may have a glass transition temperature of 0° C. or lower after photocuring.

[0017] The monofunctional (meth)acrylate monomer may include at least one of 4-hydroxybutyl acrylate (4-HBA), 2-ethylhexyl acrylate (2-EHA), tetrahydrofurfuryl acrylate (THF-A), and 2-ethylhexyl-diglycol acrylate (EHDG-AT).

[0018] The resin composition may be applied by inkjet printing or dispensing.

[0019] One embodiment provides an adhesive member comprising a polymer derived from a resin composition including at least one monofunctional (meth)acrylate monomer, a urethane (meth)acrylate oligomer having a weight average molecular weight of 5,000 or more and 100,000 or less, a dendritic polymer, and at least one photoinitiator including a radical polymerization initiator.

[0020] The adhesive member may have a storage modulus of 1 MPa or less at a frequency of 1 Hz and a temperature of -20°C.

[0021] The adhesive member may have a 180° peel strength of 800 gf / 25 mm or more at a temperature of 25° C. to at least one of a glass substrate and a polymer substrate.

[0022] The adhesive member may have a glass transition temperature of 0° C. or lower.

[0023] The weight of the dendritic polymer may be 0.5 wt % or more and 15 wt % or less based on the total weight of the resin composition.

[0024] The weight average molecular weight of the dendritic polymer may be 1,000 or more and 50,000 or less.

[0025] The dendritic polymer may include a repeating unit represented by the following formula 1: [ka] chemical formula 1 In Chemical Formula 1, R1 may be a hydrogen atom or a methyl group, and R2 may be an alkyl group having 1 to 20 carbon atoms.

[0026] The dendritic polymer may contain multifunctional thiol residues.

[0027] The dendritic polymer comprises a (meth)acrylate copolymer, and the (meth)acrylate copolymer may have a molecular weight distribution of 1.0 or more and 3.0 or less.

[0028] The resin composition may have a shear viscosity of 5 mPa·s or more and 50 mPa·s or less at 25° C. as measured by JIS Z8803 method.

[0029] One embodiment provides a display device including a display panel, a window disposed on the display panel, and an adhesive member disposed between the display panel and the window, the adhesive member including a polymer derived from a resin composition including at least one monofunctional (meth)acrylate monomer, a urethane (meth)acrylate oligomer having a weight-average molecular weight of 5,000 or more and 100,000 or less, a dendritic polymer, and at least one photoinitiator including a radical polymerization initiator.

[0030] The adhesive member may have a storage modulus of 1 MPa or less at a frequency of 1 Hz and a temperature of -20°C.

[0031] The adhesive member may have a 180° peel strength of 800 gf / 25 mm or more at a temperature of 25° C. to at least one of a glass substrate and a polymer substrate.

[0032] The adhesive member may have a glass transition temperature of 0° C. or lower.

[0033] The weight of the dendritic polymer may be 0.5 wt % or more and 15 wt % or less based on the total weight of the resin composition.

[0034] The weight average molecular weight of the dendritic polymer may be 1,000 or more and 50,000 or less.

[0035] The dendritic polymer may include a repeating unit represented by the following formula 1: [ka] chemical formula 1 In Chemical Formula 1, R1 may be a hydrogen atom or a methyl group, and R2 may be an alkyl group having 1 to 20 carbon atoms.

[0036] The dendritic polymer may contain multifunctional thiol residues.

[0037] The dendritic polymer comprises a (meth)acrylate copolymer, and the (meth)acrylate copolymer may have a molecular weight distribution of 1.0 or more and 3.0 or less.

[0038] The resin composition may have a shear viscosity of 5 mPa·s or more and 50 mPa·s or less at 25° C. as measured by JIS Z8803 method.

[0039] The display device may further include an input sensing unit disposed between the display panel and the window, and the adhesive member may be disposed between the display panel and the input sensing unit or between the input sensing unit and the window. [Effects of the Invention]

[0040] The resin composition of one embodiment includes a dendritic polymer and can exhibit low viscosity characteristics.

[0041] An adhesive member of one embodiment contains a polymer derived from the resin composition of one embodiment, and can exhibit excellent flexibility and excellent adhesive reliability.

[0042] The display device of the embodiment includes the adhesive member of the embodiment and can exhibit excellent reliability. [Brief explanation of the drawings]

[0043] [Figure 1A] 1 is a perspective view showing a display device according to an embodiment; [Figure 1B] 1 is a perspective view showing a display device according to an embodiment; [Figure 1C] 1 is a plan view illustrating a display device according to an embodiment. [Figure 1D] 1 is a perspective view showing a display device according to an embodiment; [Figure 2] 1 is an exploded perspective view showing a display device according to an embodiment; [Figure 3] 3 is a cross-sectional end view showing a portion corresponding to line II' in FIG. 2. FIG. [Figure 4] 1 is a cross-sectional end view of a portion of a display device according to one embodiment. [Figure 5A] 1A to 1C are diagrams illustrating a method for manufacturing an adhesive member according to an embodiment. [Figure 5B] 1A to 1C are diagrams illustrating a method for manufacturing an adhesive member according to an embodiment. [Figure 5C] 1A to 1C are diagrams illustrating a method for manufacturing an adhesive member according to an embodiment. [Figure 5D] 1A to 1C are diagrams illustrating a method for manufacturing an adhesive member according to an embodiment. [Figure 6A] 1A to 1C are diagrams illustrating a method for manufacturing an adhesive member according to an embodiment. [Figure 6B] 1A to 1C are diagrams illustrating a method for manufacturing an adhesive member according to an embodiment. [Figure 6C] 1A to 1C are diagrams illustrating a method for manufacturing an adhesive member according to an embodiment. [Figure 7] 1 is a cross-sectional end view illustrating a display device according to an embodiment. [Figure 8]1 is a cross-sectional end view illustrating a display device according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0044] Because the present invention can be modified in various ways and can have various forms, specific embodiments are shown by way of example in the drawings and described in detail herein, but it should be understood that this is not intended to limit the invention to the particular disclosed forms, but rather to include all modifications, equivalents, and alternatives falling within the spirit and technical scope of the invention.

[0045] As used herein, when a component (or region, layer, portion, etc.) is referred to as being "on" or "coupled" to another component, it means that it may be directly disposed, coupled, or connected to the other component, or that a third component may be disposed therebetween.

[0046] The same reference numerals refer to the same elements. In the drawings, the thickness, proportions, and dimensions of the elements are exaggerated for the purpose of effectively explaining the technical content. "And / or" includes all combinations of one or more elements defined by the associated elements.

[0047] Terms such as "first" and "second" are used to describe various components, but the components are not limited to the terms. Terms are used only to distinguish one component from another. For example, a first component may be designated as a "second component," and similarly, a second component may be designated as a "first component," without departing from the scope of the present invention. A singular expression includes a plural expression unless the context clearly dictates otherwise.

[0048] Furthermore, terms such as "under," "below," "on," and "above" are used to describe the relationship between components shown in the drawings. The terms are relative concepts and are described based on the directions shown in the drawings.

[0049] It should be understood that the terms "comprise" or "have" and the like specify the presence of any feature, number, step, operation, component, part, or combination thereof set forth above in the specification, but do not preclude the presence or possible addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0050] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by a person skilled in the art to which the present invention belongs. Furthermore, terms that are the same as those defined in commonly used dictionaries should be interpreted to have a meaning consistent with the meaning they have in the context of the relevant art, and should not be interpreted in an overly ideal or formal sense unless explicitly defined herein.

[0051] In this specification, an alkyl group may be linear or branched. The number of carbon atoms in the alkyl group may be 1 to 50, 1 to 30, 1 to 20, 1 to 10, or 1 to 6. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an s-butyl group, a t-butyl group, an i-butyl group, a 2-ethylbutyl group, a 3,3-dimethylbutyl group, an n-pentyl group, an i-pentyl group, a neopentyl group, a t-pentyl group, a 1-methylpentyl group, a 3-methylpentyl group, a 2-ethylpentyl group, a 4-methyl-2-pentyl group, an n-hexyl group, a 1-methylhexyl group, 2-ethylhexyl group, 2-butylhexyl group, n-heptyl group, 1-methylheptyl group, 2,2-dimethylheptyl group, 2-ethylheptyl group, 2-butylheptyl group, n-octyl group, t-octyl group, 2-ethyloctyl group, 2-butyloctyl group, 2-hexyloctyl group, 3,7-dimethyloctyl group, n-nonyl group, n-decyl group, adamantyl group, 2-ethyldecyl group, 2-butyldecyl group, 2-hexyl Cyldecyl group, 2-octyldecyl group, n-undecyl group, n-dodecyl group, 2-ethyldodecyl group, 2-butyldodecyl group, 2-hexyldodecyl group, 2-octyldecyl group, n-tridecyl group, n-tetradecyl group, n-pentadecyl group, n-hexadecyl group, 2-ethylhexadecyl group, 2-butylhexadecyl group, 2-hexylhexadecyl group, 2-octylhexadecyl group, n-heptadecyl group, n-octyl Examples of the alkyl group include, but are not limited to, tadecyl, n-nonadecyl, n-icosyl, 2-ethylicosyl, 2-butylicosyl, 2-hexylicosyl, 2-octylicosyl, n-henicosyl, n-docosyl, n-tricosyl, n-tetracosyl, n-pentacosyl, n-hexacosyl, n-heptacosyl, n-octacosyl, n-nonacosyl, and n-triacontyl groups.

[0052] An adhesive member and a display device including the same according to an embodiment of the present invention will be described below with reference to the accompanying drawings, in which: Figure 1A is a perspective view of a display device DD in an unfolded state according to an embodiment of the present invention;

[0053] In one embodiment, the electronic device DD may be a device activated by an electrical signal. For example, the display device DD may be, but is not limited to, a mobile phone, a tablet, a car navigation system, a game console, or a wearable device. In FIG. 1A and other figures, the display device DD is exemplarily shown as a mobile phone.

[0054] The display device DD may include a first display surface FS defined by a first directional axis DR1 and a second directional axis DR2 intersecting the first directional axis DR1. The display device DD may provide an image IM to a user via the first display surface FS. The display device DD may display the image IM on the first display surface FS in a direction of a third directional axis DR3 parallel to each of the first directional axis DR1 and the second directional axis DR2.

[0055] In this specification, the first directional axis DR1 and the second directional axis DR2 may be perpendicular to each other, and the third directional axis DR3 may be a normal direction to a plane defined by the first directional axis R1 and the second directional axis DR2. The thickness direction of the display device DD may be aligned with the third directional axis DR3. The front (or top) and back (or bottom) surfaces may face each other along the third directional axis DR3, and the normal directions of the front (or top) and back (or bottom) surfaces may be parallel to the third directional axis DR3. The front (or top) surface refers to a surface close to the first display surface FS, and the back (or bottom) surface refers to a surface separated from the first display surface FS. Alternatively, the back (or bottom) surface refers to a surface close to the second display surface RS (described later). The upper side refers to a direction approaching the first display surface FS, and the lower side refers to a direction away from the first display surface FS.

[0056] The cross section refers to a surface aligned with the thickness direction DR3, and the plane refers to a surface perpendicular to the thickness direction DR3. The plane refers to a plane defined by the first direction axis DR1 and the second direction axis DR2.

[0057] The directions indicated by the first to third directional axes DR1, DR2, and DR3 described in this specification are relative concepts and may be converted into other directions. Furthermore, the directions indicated by the first to third directional axes DR1, DR2, and DR3 may be described as the first to third directions, and the same symbols may be used.

[0058] The display device DD may detect an external input applied from the outside. The external input may include various types of input provided from outside the display device DD. For example, the external input may include contact with a part of the user's body, such as a hand, as well as external input applied by being close to the display device DD or adjacent to it at a predetermined distance (e.g., hovering). The external input may also have various forms, such as force, pressure, temperature, and light.

[0059] The display device DD may include a first display surface FS and a second display surface RS. The first display surface FS may include a first active area F-AA, a first peripheral area F-NAA, and an electronic module area EMA. The second display surface RS may be defined as a surface opposite to at least a portion of the first display surface FS. In other words, the second display surface RS may be defined as a portion of the back surface of the display device DD.

[0060] The first active area F-AA may be an area activated by an electrical signal, where an image IM is displayed, and may be an area capable of sensing various types of external inputs.

[0061] The first peripheral area F-NAA may be adjacent to the first active area F-AA. The first peripheral area F-NAA may have a predetermined color. The first peripheral area F-NAA may surround the first active area F-AA. As a result, the shape of the first active area F-AA may be substantially defined by the first peripheral area F-NAA. However, this is merely an example, and the first peripheral area F-NAA may be disposed on only one side of the first active area F-AA or may be omitted.

[0062] Various electronic modules may be arranged in the electronic module area EMA. For example, the electronic module may include at least one of a camera, a speaker, a light sensor, and a heat sensor. The electronic module area EMA may detect an external object received via the display surfaces FS and RS, or may provide an audio signal, such as a voice, to the outside via the display surfaces FS and RS. The electronic module may include multiple components and is not limited to any one embodiment.

[0063] The electronic module area EMA may be surrounded by the first peripheral area F-NAA. However, this is merely an example and is not limited to any one embodiment. For example, the electronic module area EMA may be surrounded by the first active area F-AA and the first peripheral area F-NAA, and the electronic module area EMA may be disposed within the first active area F-AA.

[0064] In one embodiment, the display device DD may be a flexible display device. The display device DD may include at least one folding area FA and multiple non-folding areas NFA1 and NFA2 extending from the folding area FA. For example, a first non-folding area NFA1, a folding area FA, and a second non-folding area NFA2 may be defined along the second direction DR2. In one embodiment, the display device DD may include the first non-folding area NFA1 and the second non-folding area NFA2 spaced apart from each other in the second direction DR2 with the folding area FA interposed therebetween. For example, the first non-folding area NFA1 may be disposed on one side of the folding area FA along the second direction DR2, and the second non-folding area NFA2 may be disposed on the other side of the folding area FA along the second direction DR2.

[0065] 1A and other figures show an embodiment of a display device DD including one folding region FA, but examples are not limited thereto, and multiple folding regions may be defined in the display device DD. For example, a display device according to an embodiment may include three or more folding regions and may also include two or more non-folding regions disposed between the folding regions.

[0066] Figures 1B, 1C, and 1D are perspective views illustrating the folding operation of a display device DD according to an embodiment, a plan view of the display device DD in a folded state, and a perspective view of the display device DD according to an embodiment, respectively.

[0067] 1B , a display device DD according to an embodiment may be folded about a first folding axis FX1 extending in a first direction DR1. When the display device DD is folded, the folding area FA may have a predetermined curvature and radius of curvature. The display device DD may be folded about the first folding axis FX1, and may be transformed into an in-folding state such that the first non-folding area NFA1 and the second non-folding area NFA2 face each other and the first display surface FS is not exposed to the outside.

[0068] 1C , when the display device DD according to an embodiment is folded inward, a second display surface RS may be visible to a user. In this case, the second display surface RS may include a second active area R-AA that displays an image. The second active area R-AA may be an area that is activated by an electrical signal. The second active area R-AA may be an area that displays an image and is capable of sensing various types of external inputs.

[0069] The second peripheral region R-NAA may be adjacent to the second active region R-AA. The second peripheral region R-NAA may have a predetermined color. The second peripheral region R-NAA may surround the second active region R-AA. Meanwhile, although not shown, the display device DD may further include an electronic module region on the second display surface RS in which electronic modules having various configurations are arranged, and is not limited to any one embodiment.

[0070] 1D , the display device DD according to an embodiment may be folded about a second folding axis FX2 extending in the first direction DR1. The display device DD may be folded about the second folding axis FX2 and transformed into an out-folding state such that the first display surface FS is exposed to the outside. In an embodiment, the display device DD may be configured to alternate between an unfolded operation and an inward or outward folding operation, but is not limited thereto.

[0071] 1A to 1D exemplarily show folding based on a folding axis FX1 or FX2, but the number of folding axes and the corresponding number of non-folding areas are not limited thereto. For example, folding based on multiple folding axes may be performed so that portions of the first display surface FS and the second display surface RS face each other. Also, while the first and second folding axes FX1 and FX2 are shown aligned with the long sides of the display device DD, the embodiment is not limited thereto, and the first and second folding axes FX1 and FX2 may be aligned with the short sides of the display device DD.

[0072] In the display device DD, the first non-folding area NFA1 and the second non-folding area NFA2 may be defined as portions having display surfaces FS and RS aligned with the plane defined by the first directional axis DR1 and the second directional axis DR2 in the folded state as shown in Fig. 1C, and the folding area FA may be defined as the area between the first non-folding area NFA1 and the second non-folding area NFA2. The folding area FA may include a curved surface portion that is bent to have a predetermined curvature in the folded state.

[0073] 2 is an exploded perspective view showing a display device DD according to one embodiment. Referring to FIG. 2, the display device DD may include a display module DM, a window WP disposed on the display module DM, and an adhesive member AP disposed between the display module DM and the window WP. The display device DD may further include a support member SM disposed below the display module DM, a protective layer PF disposed on the window WP, and a housing HAU that houses the display module DM, the support member SM, etc.

[0074] The housing HAU may include a material having a relatively high rigidity. For example, the housing HAU may include a plurality of frames and / or plates made of glass, plastic, or metal. The housing HAU may provide a predetermined storage space. The display module DM may be housed in the storage space to be protected from external impacts.

[0075] The support member SM may include a metal material or a polymer material. For example, the support member SM may be formed of stainless steel, aluminum, or an alloy thereof. Alternatively, the support member SM may be made of carbon fiber reinforced plastic (CFRP) or the like. However, the embodiment is not limited thereto, and the support member SM may include a non-metallic material, plastic, glass fiber reinforced plastic, or glass. Unlike the illustration, the support member SM may be omitted.

[0076] Although not shown, the display device DD may further include a cushioning layer, a shielding layer, etc., disposed under the support member SM. The cushioning layer may include sponge, foam, or an elastic polymer such as urethane resin. The shielding layer may be an electromagnetic wave shielding layer or a heat dissipation layer.

[0077] The display module DM may be activated by an electrical signal. The display module DM may be activated to display an image IM (FIG. 1A) on a display surface FS (FIG. 1A) of the display device DD. A display area AA-DM and a non-display area NAA-DM may be defined in the display module DM. The display area AA-DM may be an area activated by an electrical signal. The non-display area NAA-DM may be an area located adjacent to at least one side of the display area AA-DM. Circuits, wiring, etc. for driving the display area AA-DM may be arranged in the non-display area NAA-DM.

[0078] An adhesive member AP may be disposed on the display module DM. The display module DM and the window WP may be bonded by the adhesive member AP. The adhesive member AP may be optically transparent. In one embodiment, the adhesive member AP may include a polymer derived from an embodiment of a resin composition RC (FIGS. 5A and 6A) described below. The adhesive resin AP may be formed from an embodiment of the resin composition RC (FIGS. 5A and 6A). The adhesive member AP formed from the embodiment of the resin composition RC (FIGS. 5A and 6A) may exhibit excellent adhesive reliability. In one embodiment, a display device DD including an adhesive member AP formed from the resin composition RC (FIGS. 5A and 6A) may exhibit excellent reliability.

[0079] The window WP may include a glass substrate. The window WP may protect the display module DM and the like. An image IM (FIG. 1A) generated by the display panel DM may be provided to a user through the window WP. For example, the window WP may include UTG (Ultra Thin Glass).

[0080] The window WP may include a transparent area TA and a bezel area BZA. The transparent area TA may overlap at least a portion of the display area AA-DM of the display module DM. The transparent area TA may be an optically transparent area. An image IM (FIG. 1A) may be provided to a user through the transparent area TA.

[0081] The bezel area BZA may be an area having a relatively low light transmittance compared to the transmissive area TA. The bezel area BZA may define the shape of the transmissive area TA. The bezel area BZA may be adjacent to the transmissive area TA and surround the transmissive area TA.

[0082] The bezel region BZA may have a predetermined color. The bezel region BZA may cover the non-display region NAA-DM of the display module DM and block the non-display region NAA-DM from being viewed from the outside. However, the embodiment is not limited thereto, and the bezel region BZA may be disposed adjacent to only one side of the transmissive region TA, or at least a portion of the bezel region BZA may be omitted.

[0083] The protective layer PF may be a functional layer that protects one surface (e.g., the top surface) of the window WP. The protective layer PF may include an anti-fingerprint coating agent, a hard coating agent, an anti-static agent, etc. Although not shown, an auxiliary adhesive may be disposed between the window WP and the protective layer PF. Unlike the illustration, the protective layer PF may be omitted.

[0084] Fig. 3 is a cross-sectional end view showing a portion corresponding to line II' in Fig. 2. Fig. 3 is a cross-sectional end view showing a display device DD according to an embodiment. For convenience of explanation, Fig. 3 omits the housing HAU, and shows the support member SM, display module DM, adhesive member AP, window WP, and protective layer PF.

[0085] 3, the support plate SM may include a first support portion MP1 overlapping the first non-folding area NFA1 and a second support portion MP2 overlapping the second non-folding area NFA1. The first support portion MP1 and the second support portion MP2 may be separated from the folding area FA. The first support portion MP1 and the second support portion MP2 may not overlap the folding area FA. Unlike the illustration, at least a portion of the first support portion MP1 and at least a portion of the second support portion MP2 may overlap the folding area FA.

[0086] The display module DM may include a display panel DP and an input sensing unit TP disposed on the display panel DP. The display panel DP may include a base substrate BS, a circuit layer DP-CL disposed on the base substrate BS, a display element layer DP-EL disposed on the circuit layer DP-CL, and a sealing layer TFE covering the display element layer DP-EL. An adhesive member AP may be disposed between the display panel DP and the window WP.

[0087] 3 is merely an example, and the configuration of the display panel DP is not limited thereto. For example, the display panel DP may include a liquid crystal display element, in which case the sealing layer TFE may be omitted.

[0088] The base substrate BS may provide a base surface on which the circuit layers DP-CL are disposed. The base substrate BS may be a flexible substrate that can be bent, folded, rolled, etc. The base substrate BS may be a glass substrate, a metal substrate, a polymer substrate, etc. However, embodiments are not limited thereto, and the base substrate BS may include an inorganic layer, an organic layer, or a composite material layer.

[0089] The circuit layer DP-CL may include an insulating layer, a semiconductor pattern, a conductive pattern, a signal line, etc. For example, the circuit layer DP-CL may include a switching transistor and a driving transistor for driving the light-emitting element ED (FIG. 4) of the display element layer DP-EL.

[0090] The display element layer DP-EL may include a light-emitting element ED (FIG. 4) that emits light. For example, the light-emitting element ED (FIG. 4) may include an organic light-emitting material, an inorganic light-emitting material, an organic-inorganic light-emitting material, a quantum dot, a quantum rod, a micro-LED, or a nano-LED.

[0091] The encapsulating layer TFE may be disposed on the display element layer DP-EL. The encapsulating layer TFE may protect the light-emitting element layer DP-EL from foreign substances such as moisture, oxygen, and / or dust particles. The encapsulating layer TFE may include at least one inorganic layer. Alternatively, the encapsulating layer TFE may include at least one organic layer and at least one inorganic layer. For example, the encapsulating layer TFE may include an inorganic layer, an organic layer, and an inorganic layer that are stacked in sequence.

[0092] The input sensing unit TP may be disposed on the display panel DP, for example, the input sensing unit TP may be disposed directly on the encapsulation layer TFE of the display panel DP.

[0093] As used herein, when one component is placed / provided directly on another component, it means that there is no third component placed / provided between the two components. In other words, when one component is 'placed / provided' directly on another component, it means that the two components are in 'contact' with each other.

[0094] The input sensing unit TP may sense an external input, convert it into a predetermined input signal, and provide the input signal to the display panel DP. For example, in one embodiment of the display device DD, the input sensing unit TP may be a touch sensing unit that senses a touch. The input sensing unit TP may recognize a direct touch by a user, an indirect touch by a user, a direct touch by an object, or an indirect touch by an object.

[0095] The input sensing unit TP may sense at least one of the position and intensity (pressure) of an externally applied touch. In an embodiment, the input sensing unit TP may have various structures or be made of various materials and is not limited to any one embodiment. For example, the input sensing unit TP may sense an external input using a capacitive method. The display panel DP may receive an input signal from the input sensing unit TP and generate an image corresponding to the input signal.

[0096] The window WP may include a base layer BL and a print layer BM. Although not shown, the window WP may further include at least one functional layer (not shown) provided on the base layer BL. For example, the functional layer (not shown) may be a hard coating layer, an anti-fingerprint coating layer, etc., but embodiments are not limited thereto.

[0097] The base layer BL may be a glass substrate, or may be a plastic substrate. For example, the base layer BL may be formed of polyimide, polyacrylate, polymethyl methacrylate, polycarbonate, polyethylene naphthalate, polyvinylidene chloride, polyvinylidene fluoride, polystyrene, ethylene-vinyl alcohol copolymer, or a combination thereof.

[0098] The print layer BM may be disposed on one surface of the base layer BL. The print layer BM may be provided on the lower surface of the base layer BL adjacent to the display module DM. The print layer BM may be disposed in an edge region of the base layer BL. The print layer BM may be an ink print layer. The print layer BM may also be a layer formed containing a pigment or dye. In the window WP, the bezel region BZA may be a portion where the print layer BM is provided.

[0099] A step SP-a may exist between the print layer BM and a portion of the base layer BL where the print layer BM is not provided. The adhesive member AP formed from the resin composition RC according to one embodiment (FIGS. 5A and 6A) has excellent flexibility and adhesive strength, and therefore can be attached to the window WP at the step SP-a without lifting.

[0100] An adhesive member AP may be disposed between the display panel DP and the window WP. An adhesive member AP may be disposed between the input sensing unit TP disposed on the display panel DP and the window WP.

[0101] The thickness T0 of the adhesive member AP may be 50 μm or more and 200 μm or less. For example, the thickness T0 of the adhesive member AP may be 50 μm or more and 100 μm or less. However, these are merely examples, and the thickness T0 of the adhesive member AP is not limited to these.

[0102] In one embodiment, the adhesive member AP may have a storage modulus of 1 MPa or less at a frequency of 1 Hz and a temperature of -20°C. In this specification, the storage modulus refers to a value measured in shear (torsion) mode. An adhesive member having a storage modulus of more than 1 MPa at a frequency of 1 Hz and a temperature of -20°C is vulnerable to external impact, has very low flexibility, and is unsuitable for use in a display device. In contrast, an adhesive member according to one embodiment having a storage modulus of 1 MPa or less at a frequency of 1 Hz and a temperature of -20°C may exhibit excellent impact resistance and excellent flexibility. In one embodiment, a display device DD including the adhesive member AP may exhibit excellent reliability.

[0103] In one embodiment, the adhesive member AP may have a 180° peel strength of 800 gf / 25 mm or more from at least one of a glass substrate and a polymer substrate at a temperature of 25° C. The adhesive member AP may have a 180° peel strength of 2100 gf / 25 mm or less from at least one of a glass substrate and a polymer substrate at a temperature of 25° C. For example, the polymer substrate may include polyethylene terephthalate (PET). An adhesive member AP having a 180° peel strength of 800 gf / 25 mm or more from at least one of a glass substrate and a polymer substrate at a temperature of 25° C. may exhibit excellent adhesive reliability. A display device DD including an adhesive member AP having a 180° peel strength of 800 gf / 25 mm or more from at least one of a glass substrate and a polymer substrate at a temperature of 25° C. may exhibit excellent reliability. In contrast, an adhesive member having a 180° peel strength of less than 800 gf / 25 mm from at least one of a glass substrate and a polymer substrate at a temperature of 25° C. may have low adhesive strength and, when included in a display device, may peel from the display device components (e.g., a display module and / or a window).

[0104] For example, the adhesive member AP may have a 180° peel strength of 500 gf / 25 mm or more and 1200 gf / 25 mm or less against at least one of a glass substrate and a polymer substrate at a temperature of 60° C. However, this is merely an example, and the embodiment is not limited thereto.

[0105] In one embodiment, the adhesive member AP may have a glass transition temperature (Tg) of 0°C or less. Adhesives with a glass transition temperature exceeding 0°C have very high cohesive strength of the polymer constituting the adhesive member, making them vulnerable to external impact and unsuitable for use in display devices. In contrast, adhesive members AP with a glass transition temperature of 0°C or less in one embodiment may exhibit good cohesive strength of the polymer constituting the adhesive member AP and may exhibit excellent impact resistance. In one embodiment, a display device DD including an adhesive member AP with a glass transition temperature of 0°C or less may exhibit excellent reliability.

[0106] For example, the adhesive member AP may have a glass transition temperature of −32° C. or lower. In one embodiment, the adhesive member AP having a glass transition temperature of −32° C. or lower may exhibit properties that allow for easy repeated folding and unfolding in a relatively low temperature environment. In one embodiment, the adhesive member AP having a glass transition temperature of −32° C. or lower may exhibit excellent properties suitable for use in a flexible display device DD.

[0107] In one embodiment, the adhesive resin AP may be formed from one embodiment of the resin composition RC (FIGS. 5A and 6A), whereby the adhesive member AP of one embodiment may satisfy the storage modulus, 180° peel strength, and glass transition temperature described above.

[0108] Fig. 4 is a cross-sectional end view specifically showing the display module DM of Fig. 3. The configuration of the display module DM shown in Fig. 4 is an example, and the embodiment is not limited thereto.

[0109] In FIG. 4, the base substrate BS may include a single layer or multiple layers. For example, the base substrate BS may include a first synthetic resin layer, a multilayer or single-layer inorganic layer, and a second synthetic resin layer disposed on the multilayer or single-layer inorganic layer. Each of the first synthetic resin layer and the second synthetic resin layer may include a polyimide-based resin. Each of the first synthetic resin layer and the second synthetic resin layer may also include at least one of an acrylic-based resin, a methacrylic-based resin, a polyisoprene-based resin, a vinyl-based resin, an epoxy-based resin, a urethane-based resin, a cellulose-based resin, a siloxane-based resin, a polyamide-based resin, and a perylene-based resin. In this specification, a "XX-based" resin means that the resin contains the functional group "XX."

[0110] The display panel DP may include a transistor TR and a light-emitting element ED. The transistor TR and the light-emitting element ED may be disposed on a base substrate BS. Although one transistor TR is shown in FIG. 4, the display panel DP may actually include multiple transistors and at least one capacitor for driving the light-emitting element ED.

[0111] The circuit layer DP-CL may be disposed on a base substrate BS. The circuit layer DP-CL may include a shielding electrode BML, a transistor TR, a connection electrode CNE, and a plurality of insulating layers BFL and INS1-INS6. The plurality of insulating layers BFL and INS1-INS6 may include a buffer layer BFL and first to sixth insulating layers INS1-INS6. However, the layered structure of the circuit layer DP-CL shown in FIG. 4 is merely an example, and the layered structure of the circuit layer DP-CL may be changed depending on the configuration of the display panel DP and the process of the circuit layer DP-CL, etc.

[0112] The shielding electrode BML may be disposed on the base substrate BS. The shielding electrode BML may overlap the transistor TR. The shielding electrode BML may protect the transistor TR by blocking light incident on the transistor TR from below the display panel DP. The shielding electrode BML may include a conductive material. When a voltage is applied to the shielding electrode BML, the threshold voltage of the transistor TR disposed above the shielding electrode BML may be maintained. However, embodiments are not limited thereto, and the shielding electrode BML may be a floating electrode. The shielding electrode BML may be omitted.

[0113] The buffer layer BFL may be disposed on the base substrate BS and cover the light-shielding electrode BML. The buffer layer BFL may include an inorganic layer. The buffer layer BFL may improve the bonding strength between the semiconductor pattern or the conductive pattern disposed on the buffer layer BFL and the base substrate BS.

[0114] The transistor TR may include a source S1, a channel C1, a drain D1, and a gate G1. The source S1, the channel C1, and the drain D1 of the transistor TR may be formed of a semiconductor pattern. The semiconductor pattern of the transistor TR may include polysilicon, amorphous silicon, or metal oxide, but is not limited to any one of them and may be applied without limitation as long as it has semiconductor properties.

[0115] The semiconductor pattern may include a plurality of regions differentiated by the magnitude of conductivity. Regions of the semiconductor pattern that are doped with a dopant or have a reduced metal oxide may have high conductivity and may substantially function as the source and drain electrodes of the transistor TR. The regions of the semiconductor pattern that are high in conductivity may correspond to the source S1 and drain D1 of the transistor TR. Regions of the semiconductor pattern that are undoped or lightly doped or have a non-reduced metal oxide and have low conductivity may correspond to the channel C1 (or active) of the transistor TR.

[0116] A first insulating layer INS1 may be disposed on the buffer layer BFL while covering the semiconductor pattern of the transistor TR. A gate G1 of the transistor TR may be disposed on the first insulating layer INS1. In a plan view, the gate G1 may overlap the channel C1 of the transistor TR. The gate G1 may function as a mask in a process of doping the semiconductor pattern of the transistor TR.

[0117] A second insulating layer INS2 may be disposed on the first insulating layer INS1 while covering the gate G1. A third insulating layer INS3 may be disposed on the second insulating layer INS2.

[0118] The connection electrode CNE may include a first connection electrode CNE1 and a second connection electrode CNE2 for electrically connecting the transistor TR and the light emitting element ED. However, the configuration of the connection electrode CNE for electrically connecting the transistor TR and the light emitting element ED is not limited thereto, and one of the first and second connection electrodes CNE1 and CNE2 may be omitted, or an additional connection electrode may be further included.

[0119] The first connection electrode CNE1 may be disposed on the third insulating layer INS3. The first connection electrode CNE1 may be connected to the first drain D1 via a first contact hole CH1 that penetrates the first to third insulating layers INS1 to INS3. The fourth insulating layer INS4 may be disposed on the third insulating layer INS3 while covering the first connection electrode CNE1. The fifth insulating layer INS5 may be disposed on the fourth insulating layer INS4.

[0120] The second connection electrode CNE1 may be disposed on the fifth insulating layer INS5. The second connection electrode CNE2 may be connected to the first connection electrode CNE1 via a second contact hole CH2 that penetrates the fourth and fifth insulating layers INS4 and INS5. The sixth insulating layer INS6 may be disposed on the fifth insulating layer INS5 while covering the second connection electrode CNE2.

[0121] Each of the first to sixth functional layers INS1 to INS6 may include an inorganic layer or an organic layer. For example, the inorganic layer may include at least one of aluminum oxide, titanium oxide, silicon oxide, silicon oxynitride, zirconium oxide, and hafnium oxide. The organic layer may include at least one of acrylic resin, methacrylic resin, polyisoprene resin, vinyl resin, epoxy resin, urethane resin, cellulose resin, siloxane resin, polyamide resin, and ferrylene resin.

[0122] The display element layer DP-EL may include a pixel defining layer PDL and a light emitting element ED. The light emitting element ED may include a first electrode AE, a hole control layer HCL, an emitting layer EML, an electron control layer TCL, and a second electrode CE.

[0123] The first electrode AE ​​may be disposed on the sixth insulating layer INS6. The first electrode AE ​​may be connected to the second connection electrode CNE2 via a third contact hole CH3 that penetrates the sixth insulating layer INS6. The first electrode AE ​​may be electrically connected to the drain D1 of the transistor TR via the first and second connection electrodes CNE1 and CNE2.

[0124] The first electrode AE ​​may be formed of a metal material, a metal alloy, or a conductive compound. The first electrode AE ​​may be an anode or a cathode. However, the embodiment is not limited thereto. The first electrode AE ​​may also be a pixel electrode. The first electrode AE ​​may be a transmissive electrode, a semi-transmissive electrode, or a reflective electrode. The first electrode AE ​​may include at least one selected from Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF, Mo, Ti, W, In, Sn, and Zn, a compound of 22 or more selected from these elements, a mixture of two or more selected from these elements, or an oxide thereof.

[0125] If the first electrode AE ​​is a transmissive electrode, it may include a transparent metal oxide, such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), or indium tin zinc oxide (ITZO). If the first electrode AE ​​is a semi-transmissive or reflective electrode, it may include Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF / Ca (a laminated structure of LiF and Ca), LiF / Al (a laminated structure of LiF and Al), Mo, Ti, W, or a compound or mixture thereof (e.g., a mixture of Ag and Mg). Alternatively, the first electrode AE ​​may have a multi-layer structure including a reflective or semi-transmissive film formed of these materials and a transparent conductive film formed of ITO, IZO, ZnO, ITZO, or the like. For example, the first electrode AE ​​may have an ITO / Ag / ITO triple-layer structure, but is not limited thereto. Furthermore, the embodiment is not limited thereto, and the first electrode AE ​​may include the above-mentioned metal material, a combination of two or more metal materials selected from the above-mentioned metal materials, or an oxide of the above-mentioned metal material.

[0126] A pixel defining layer PDL may be disposed on the sixth insulating layer INS6. A light emitting opening PX_OP exposing a portion of the first electrode AE ​​may be defined in the pixel defining layer PDL. The portion of the first electrode AE ​​exposed by the light emitting opening PX_OP may be defined as a light emitting area LA.

[0127] The display area AA-DM of the display module DM may include a light-emitting area LA and a light-shielding area NLA. The area where the pixel definition film PDL is arranged may correspond to the light-shielding area NLA. The light-shielding area NLA may surround the light-emitting area LA within the display area AA-DM.

[0128] The hole control layer HCL may be disposed on the first electrode AE ​​and the pixel defining layer PDL. The hole control layer HCL may be provided as a common layer overlapping the light emitting region LA and the light blocking region NLA. Alternatively, the hole control layer HCL may be provided only in the region corresponding to the light emitting opening PX-OP. The hole control layer HCL may include at least one of a hole transport layer, a hole injection layer, and an electron blocking layer. The hole control layer HCL may include a known hole injection material and / or a known hole transport material.

[0129] The emitting layer EML may be disposed on the hole controlling layer HCL. The emitting layer EML may be disposed in a region corresponding to the light emitting opening PX_OP. Alternatively, the emitting layer EML may be provided as a common layer. The emitting layer EML may include an organic light emitting material and / or an inorganic light emitting material. The emitting layer EML may emit any one of red, green, and blue light. For example, the emitting layer EML may emit blue light.

[0130] The electron control layer TCL may be disposed on the light-emitting layer EML. The electron control layer TCL may be provided as a common layer overlapping the light-emitting region LA and the light-shielding region NLA. Alternatively, the electron control layer TCL may be provided only in the region corresponding to the light-emitting aperture PX-OP. The electron control layer TCL may include at least one of an electron transport layer, an electron injection layer, and a hole blocking layer. The electron control layer TCL may include a known electron injection material and / or a known electron transport material.

[0131] The second electrode CE may be disposed on the electronic control layer TCL. The second electrode CE may be provided as a common layer overlapping the light emitting area LA and the light blocking area NLA.

[0132] The second electrode CE may be a common electrode. The second electrode CE may be a cathode or an anode, but the embodiment is not limited thereto. For example, if the first electrode AE ​​is an anode, the second electrode may be a cathode, and if the first electrode AE ​​is a cathode, the second electrode CE may be an anode.

[0133] The second electrode CE may be a transmissive electrode, a semi-transmissive electrode, or a reflective electrode. If the second electrode CE is a transmissive electrode, the second electrode CE may be formed of a transparent metal oxide, such as ITO, IZO, ZnO, or ITZO.

[0134] If the second electrode CE is a semi-transmissive electrode or a reflective electrode, the second electrode CE may include Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF / Ca, LiF / Al, Mo, Ti, Yb, W, or a compound or mixture containing any of these (e.g., AgMg, AgYb, or MgYb). Alternatively, the second electrode CE may have a multi-layer structure including a reflective or semi-transmissive film formed of the above material and a transparent conductive film formed of ITO, IZO, ZnO, ITZO, or the like. For example, the second electrode CE may include any of the above-mentioned metal materials, a combination of two or more metal materials selected from the above-mentioned metal materials, or oxides of the above-mentioned metal materials.

[0135] The encapsulation layer TFE may be disposed on the second electrode CE to cover the light-emitting element ED. The encapsulation layer TFE may include multiple thin films. For example, the encapsulation layer TFE may include an inorganic film disposed on the second electrode CE and an organic film disposed between the inorganic films. The inorganic film may protect the light-emitting element ED from moisture / oxygen, and the organic film may protect the light-emitting element ED from foreign matter such as dust particles.

[0136] The input sensing unit TP may include a first sensing insulating layer IL1, a second sensing insulating layer IL2, and a third sensing insulating layer IL3. The input sensing unit TP may include at least one conductive layer disposed on the sensing insulating layer. The input sensing unit TP may include a first conductive layer CDL1 and a second conductive layer CDL2.

[0137] The first sensing insulating layer IL1 may be disposed on the sealing layer TFE. The first sensing insulating layer IL1 may include at least one inorganic insulating layer. The first sensing insulating layer IL1 may be in contact with the sealing layer TFE. Alternatively, the first sensing insulating layer IL1 may be omitted, in which case the first conductive layer CD1 may be in contact with the sealing layer TFE.

[0138] The first conductive layer CDL1 may be disposed on the first sense insulating layer IL1. The first conductive layer CDL1 may include a plurality of first conductive patterns. The plurality of first conductive patterns may be disposed on the first sense insulating layer IL1. The second sense insulating layer IL2 may be disposed on the first sense insulating layer IL1 to cover at least a portion of the first conductive layer CDL1.

[0139] The second conductive layer CDL2 may be disposed on the second sensor insulating layer IL2. The second conductive layer CDL2 may include a plurality of second conductive patterns. The plurality of second conductive patterns may be disposed on the second sensor insulating layer IL2. Each of the plurality of second conductive patterns may be connected to the plurality of first conductive patterns via a contact hole formed in the second sensor insulating layer IL2.

[0140] The plurality of first conductive patterns of the first conductive layer CDL1 and the plurality of second conductive patterns of the second conductive layer CDL2 may be arranged to correspond to the light-shielding region NLA. The plurality of first conductive patterns of the first conductive layer CDL1 and the plurality of second conductive patterns of the second conductive layer CDL2 may correspond to a mesh pattern.

[0141] The third sensing insulating layer IL3 may be disposed on the second sensing insulating layer IL2 and cover the second conductive layer CDL2. Each of the second sensing insulating layer IL2 and the third sensing insulating layer IL3 may include an inorganic insulating layer or an organic insulating layer.

[0142] The first conductive layer CDL1 and the second conductive layer CDL2 may each have a single-layer structure or a multi-layer structure stacked along the third direction DR3. The single-layer conductive layers CDL1 and CDL2 may include a metal layer or a transparent conductive layer. The metal layer may include molybdenum, silver, titanium, copper, aluminum, or an alloy thereof. The transparent conductive layer may include a transparent conductive oxide such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), or indium zinc tin oxide (ITO). The transparent conductive layer may also include a conductive polymer such as PEDOT, a metal nanowire, graphene, or the like.

[0143] The multilayer conductive layers CDL1 and CDL2 may include a metal layer. The metal layer may have a three-layer structure such as titanium (Ti) / aluminum (Al) / titanium (Ti). The multilayer conductive layers CDL1 and CDL2 may include at least one metal layer and at least one transparent conductive layer.

[0144] 5A to 5D are schematic diagrams illustrating a method for manufacturing an adhesive member AP (FIG. 3) from a resin composition RC according to one embodiment. For example, the method for manufacturing the adhesive member AP (FIG. 3) may include the steps of providing a resin composition RC on a substrate CF, applying a first light UV-1 to the resin composition RC to form a preliminary adhesive member P-AP, and applying a second light UV-2 to the preliminary adhesive member P-AP to form the adhesive member AP (FIG. 3). In the following description of FIGS. 5A and 5D, overlapping content with that described with reference to FIGS. 1 to 4 will not be repeated, and the differences will be focused on.

[0145] Referring to FIG. 5A, in one embodiment, a resin composition RC may be provided on a substrate CF. The resin composition RC may be provided on the substrate CF through a nozzle NZ. For example, the substrate CF on which the resin composition RC is provided may include polyethylene terephthalate (PET). The substrate CF is a temporary substrate used to form an adhesive member AP (FIG. 3) from the resin composition RC, and may be any substrate that can be easily removed after the resin composition RC is cured. One surface of the substrate CF on which the resin composition RC is provided may be subjected to a release treatment.

[0146] In one embodiment, the resin composition RC may be provided by an inkjet printing method or a dispensing method. In one embodiment, the liquid resin composition RC may be provided in a uniform amount and / or at a uniform rate. Although FIG. 5A illustrates the resin composition RC being provided through a nozzle NZ, the device for providing the resin composition RC is not limited thereto.

[0147] In one embodiment, the resin composition may have a shear viscosity of 5 mPa·s or more and 50 mPa·s or less, as measured by JIS Z8803 at 25°C. Resin compositions RC having a shear viscosity of 5 mPa·s or more and 50 mPa·s or less, as measured by JIS Z8803 at 25°C, exhibit low viscosity characteristics and may be applied by inkjet printing or dispensing. Resin compositions having a shear viscosity of less than 5 mPa·s, as measured by JIS Z8803 at 25°C, may sag when applied. "Sagging" refers to the phenomenon in which the resin composition flows away from the component to which it is applied. Resin compositions having a shear viscosity of more than 50 mPa·s, as measured by JIS Z8803 at 25°C, are difficult to dispense from equipment such as a nozzle NZ, and are not applied in a uniform amount and / or thickness.

[0148] In one embodiment, the resin composition RC may include at least one monofunctional (meth)acrylate monomer, a urethane (meth)acrylate oligomer having a weight-average molecular weight of 5,000 to 100,000, a dendritic polymer, and at least one photoinitiator. In one embodiment, the photoinitiator may include a radical polymerization initiator. As used herein, "(meth)acryloyl" refers to an acryloyl group or a methacryloyl group, and "(meth)acrylic" refers to an acrylic or methacrylic group.

[0149] The resin composition RC may include at least one monofunctional (meth)acrylate monomer. For example, the weight of the monofunctional (meth)acrylate monomer may be 75 wt% or more and 85 wt% or less based on the total weight of the resin composition (100 wt%). However, this is merely an example, and the weight of the monofunctional (meth)acrylate monomer is not limited to this.

[0150] The monofunctional (meth)acrylate monomer may include at least one of an alicyclic (meth)acrylate, a hydroxyl-containing (meth)acrylate, an alkyl (meth)acrylate, and an aromatic (meth)acrylate. For example, the monofunctional (meth)acrylate monomer may include at least one of 4-hydroxybutyl acrylate (4-HBA), 2-ethylhexyl acrylate (2-EHA), tetrahydrofurfuryl acrylate (THF-A), and 2-ethylhexyl-diglycol acrylate (EHDG-AT).

[0151] In one embodiment, the resin composition RC includes at least one urethane (meth)acrylate oligomer. The urethane (meth)acrylate oligomer has a weight-average molecular weight of 5,000 to 100,000. The urethane (meth)acrylate oligomer having a weight-average molecular weight of 5,000 to 100,000 is included in the resin composition RC in a state where it has a relatively high degree of polymerization, and maintains this high degree of polymerization even after photocuring, thereby forming an adhesive member AP with excellent adhesive reliability.

[0152] For example, the weight of the urethane (meth)acrylate oligomer may be 10 wt% or more and 15 wt% or less based on the total weight of the resin composition RC. The weight of the urethane (meth)acrylate oligomer may be 11 wt% or more and 13 wt% or less based on the total weight of the resin composition RC. However, these are merely examples, and the weight of the urethane (meth)acrylate oligomer is not limited to these.

[0153] In the resin composition RC, the urethane (meth)acrylate oligomer may include at least one of UF-C051 (urethane acrylate, manufactured by Kyoeisha Chemical Co., Ltd.), UF-C052 (urethane acrylate, manufactured by Kyoeisha Chemical Co., Ltd.), and UN6304 (urethane acrylate, manufactured by Negami Chemical Industrial Co., Ltd.), although this is merely an example and the urethane (meth)acrylate oligomer contained in the resin composition RC is not limited thereto.

[0154] In one embodiment, the resin composition RC may contain a dendritic polymer. A dendritic polymer refers to a polymer having a "dendritic structure," which refers to a structure including a core and arms bonded directly or indirectly to the core. The core may be composed of a single element or multiple elements. The branches may be composed of multiple elements.

[0155] A resin composition containing a polymer may selectively segregate at the interface with air as the resin composition cures, thereby increasing the cohesive strength at the interface. In one embodiment, the resin composition RC contains a dendritic polymer, which may efficiently segregate at the interface by reducing entanglement between polymer chains or between the polymer and matrix monomer. Therefore, an adhesive member AP made of an embodiment of the resin composition RC containing a dendritic polymer may exhibit reduced rigidity. In one embodiment, an adhesive member AP (FIG. 3) made of the resin composition RC containing the dendritic polymer may satisfy the storage modulus, 180° peel strength, and glass transition temperature described above.

[0156] The weight of the dendritic polymer may be 0.5 wt% to 15 wt%, based on 100 wt% of the total weight of the resin composition RC. Adhesives made from resin compositions containing less than 0.5 wt% of the dendritic polymer, based on 100 wt% of the total weight of the resin composition RC, exhibit low 180° peel strength and are unsuitable for use in flexible display devices. Adhesives made from resin compositions containing more than 15 wt% of the dendritic polymer, based on 100 wt% of the total weight of the resin composition RC, exhibit high elastic modulus and poor shape retention. In contrast, adhesives AP (Figure 3) made from resin compositions containing 0.5 wt% to 15 wt% of the dendritic polymer, based on 100 wt% of the total weight of the resin composition RC, may exhibit excellent shape retention and exhibit properties suitable for use in flexible display devices.

[0157] In one embodiment, the weight-average molecular weight of the dendritic polymer may be 1,000 or more and 50,000 or less. For example, the weight-average molecular weight of the dendritic polymer may be 5,000 or more and 30,000 or less. A resin composition RC containing a dendritic polymer having a weight-average molecular weight of 1,000 or more and 50,000 or less may satisfy the above-mentioned shear viscosity, and an adhesive member AP (FIG. 3) made of the resin composition RC may satisfy the above-mentioned storage modulus, 180° peel strength, and glass transition temperature.

[0158] In one embodiment, the glass transition temperature of the dendritic polymer may be 25° C. or higher and 180° C. or lower. For example, the glass transition temperature of the dendritic polymer may be 50° C. or higher and 150° C. or lower, or 80° C. or higher and 120° C. or lower. A resin composition RC containing a dendritic polymer having a glass transition temperature of 25° C. or higher and 180° C. or lower may satisfy the above-mentioned shear viscosity, and an adhesive member AP ( FIG. 3 ) made of the resin composition RC may satisfy the above-mentioned storage modulus, 180° peel strength, and glass transition temperature.

[0159] In one embodiment, the dendritic polymer may have a molecular weight distribution (Polydispersity Index, PDI) of 1.0 or more and 3.0 or less. The molecular weight distribution is the weight average molecular weight (Mw) divided by the number average molecular weight (Mn). A larger molecular weight distribution value indicates a wider molecular weight distribution from low to high molecular weights, and a smaller molecular weight distribution value indicates a narrower molecular weight distribution from low to high molecular weights. A resin composition RC containing a dendritic polymer having a molecular weight distribution of 1.0 or more and 3.0 or less may satisfy the above-mentioned shear viscosity, and an adhesive member AP (FIG. 3) made of the resin composition RC may satisfy the above-mentioned storage modulus, 180° peel strength, and glass transition temperature.

[0160] The dendritic polymer may comprise a (meth)acrylate copolymer. The dendritic polymer may comprise a copolymer comprising a first repeat unit derived from a first monomer and a second repeat unit derived from a second monomer. For example, the first monomer may comprise methyl methacrylate (MMA) and the second monomer may comprise isobornyl methacrylate (IBXMA).

[0161] In one embodiment, the dendritic polymer may contain a polyfunctional thiol residue. The thiol residue refers to a compound derived from a compound containing a thiol group (-SH). The dendritic polymer may be synthesized by a radical polymerization method using a polyfunctional initiator and / or a radical polymerization method using a polyfunctional chain transfer agent. The free radical polymerization method using a polyfunctional chain transfer agent containing a polyfunctional thiol residue may exhibit excellent efficiency due to the wide variety of polyfunctional thiol residues available and the ease of synthesis.

[0162] In one embodiment, the dendritic polymer may include a repeating unit represented by the following Chemical Formula 1. The dendritic polymer may include a repeating unit containing an ester group. A resin composition RC including a dendritic polymer including a repeating unit represented by Chemical Formula 1 may satisfy the above-mentioned shear viscosity, and an adhesive member AP (FIG. 3) made of the resin composition RC may satisfy the above-mentioned storage modulus, 180° peel strength, and glass transition temperature.

[0163] [ka] chemical formula 1

[0164] In Chemical Formula 1, R1 may be a hydrogen atom or a methyl group, and R2 may be an alkyl group having from 1 to 20 carbon atoms. The alkyl group may be a straight-chain alkyl group or a branched-chain alkyl group.

[0165] In one embodiment, the resin composition RC includes at least one photoinitiator. The photoinitiator may include a radical polymerization initiator. For example, the resin composition RC may include Omnirad 819 (manufactured by IGM Resin) as the photoinitiator.

[0166] When the resin composition RC includes multiple photoinitiators, the different photoinitiators may be activated by ultraviolet light with different center wavelengths. For example, the photoinitiators may include at least one of 2,2-dimethoxy-1,2-diphenylethan-1-one, 1-hydroxycyclohexylphenylketone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 2-hydroxy-1-[4-(2-hydroxyethoxy)phenyl]-2-methyl-1-propanone, and 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)-benzyl]phenyl}-2-methylpropan-1-one.

[0167] Also, the photoinitiator may be 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1,2-dimethylamino-2-(4-methyl-benzyl)-1-(4-morpholin-4-yl-phenyl)-butan-1-one, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, ethyl(2,4,6-trimethylbenzoyl) ... The compound may include at least one of phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, [1-(4-phenylsulfanylbenzoyl)heptylideneamino]benzoate, [1-[9-ethyl-6-(2-methylbenzoyl)carbazol-3-yl]ethylideneamino]acetate, and bis(2,4-cyclopentadienyl)bis[2,6-difluoro-3-(1-pyrryl)phenyl]titanium(IV).

[0168] In one embodiment, the resin composition RC may be solvent-free. A solvent refers to a liquid for dissolving materials (e.g., monomers, oligomers, etc.) that constitute the composition. A resin composition that includes a solvent requires a drying period after application. In contrast, the resin composition RC of one embodiment that does not include a solvent does not require a drying period after application, and may be applied by inkjet printing or dispensing, thereby exhibiting excellent manufacturing efficiency.

[0169] Referring to FIG. 5B, a first light UV-1 may be applied to a resin composition RC that has been applied to a substrate CF with a uniform thickness. The liquid resin composition RC may be cured by the first light UV-1 to form a preliminary adhesive member P-AP (FIG. 5C). The first light UV-1 is ultraviolet light. Although FIG. 5B illustrates the resin composition RC applied to the substrate CF being directly irradiated with the first light UV-1 to form the preliminary adhesive member P-AP, the embodiment is not limited thereto. A carrier film (not shown) may be disposed on the resin composition RC that has been applied to a uniform thickness, and the carrier film (not shown) may be transparent to ultraviolet light.

[0170] 5C and 5D, the preliminary adhesive member P-AP formed by irradiating the resin composition RC with the first light UV-1 (FIG. 5B) may be detached from the substrate CF and provided on one side of the window WP or one side of the display module DM. One side of the preliminary adhesive member P-AP may be laminated on one side of the window WP or one side of the display module DM, and the remaining side of the preliminary adhesive member P-AP may be attached to the unattached side of the window WP or one side of the display module DM. Next, the preliminary adhesive member P-AP may be irradiated with the second light UV-2 to form the adhesive member AP. The second light UV-2 may be ultraviolet light. The second light UV-2 may be provided from above the window WP, and the window WP may transmit the second light UV-2. The second light UV-2 may be provided to the preliminary adhesive member P-AP via the window WP.

[0171] 5A to 5D, the adhesive member AP (FIG. 3) is formed by curing the resin composition RC twice (i.e., by applying light twice), but the embodiment is not limited thereto. For example, the adhesive member AP (FIG. 3) may be formed by curing the resin composition RC (FIG. 5A) once, or may be formed by curing the resin composition RC (FIG. 5A) three or more times.

[0172] In one embodiment, the resin composition RC (FIG. 5A) may include at least one monofunctional (meth)acrylate monomer, a urethane (meth)acrylate oligomer having a weight-average molecular weight of 5,000 to 100,000, a dendritic polymer, and at least one photoinitiator including a radical polymerization initiator. The resin composition RC (FIG. 5A) may be cured by UV-1 or UV-2 light. For example, the resin composition RC (FIG. 5A) may be cured by ultraviolet light to form the adhesive member AP (FIG. 3). After being cured by light, the resin composition RC (FIG. 5A) may have a storage modulus of 1 MPa or less at a frequency of 1 Hz and a temperature of -20°C. After being cured by light, the resin composition RC (FIG. 5A) may have a 180° peel strength of 800 gf / 25 mm or more from at least one of a glass substrate and a polymer substrate at 25°C. After being cured by light, the resin composition RC (FIG. 5A) may have a glass transition temperature of 0°C or less. For example, the resin composition RC (FIG. 5A) of one embodiment may have a glass transition temperature of −32° C. or lower after being cured by light. The resin composition RC (FIG. 5A) of one embodiment may contain a monofunctional (meth)acrylate monomer, a urethane (meth)acrylate oligomer, a dendritic polymer, and a radical polymerization initiator, and may satisfy the storage modulus, 180° peel strength, and glass transition temperature described above.

[0173] 6A to 6C are diagrams schematically illustrating another method for producing an adhesive member AP from a resin composition RC according to one embodiment. In the following description of FIGS. 6A to 6C, the same content as that described with reference to FIGS. 1 to 5D will not be repeated, and the differences will be mainly described.

[0174] 6A to 6C may include the steps of providing a resin composition RC on a display module DM, applying a first light UV-1 to the resin composition RC to form a preliminary adhesive member P-AP, and applying a second light UV-2 to the preliminary adhesive member P-AP to form the adhesive member AP. Compared to the manufacturing method shown in FIGS. 5A to 5D, the manufacturing method shown in FIGS. 6A to 6C differs in that a resin composition RC is provided on the display module DM.

[0175] The resin composition RC may be provided directly on one surface of the display module DM or one surface of the window WP. Figure 6A shows the case where the resin composition RC is provided directly on one surface of the display module DM.

[0176] Resin composition RC having a shear viscosity of 5 mPa·s or more and 50 mPa·s or less, as measured by JIS Z8803 at 25°C, may be applied to cover the curved portion of the step SP-b in the display module DM. By having a low viscosity of 50 mPa·s or less, resin composition RC may be applied to avoid leaving any empty space in curved portions such as the step SP-b. Furthermore, resin composition RC having a shear viscosity of 5 mPa·s or more may be applied uniformly to a predetermined thickness without dripping beyond the portion where resin composition RC is to be applied, i.e., the display module DM.

[0177] Referring to FIG. 6B, a first light UV-1 may be applied to the uniformly applied resin composition RC. By applying the first light UV-1 to the resin composition RC, a preliminary adhesive member P-AP may be formed. Referring to FIG. 6C, a window WP may be provided on the preliminary adhesive member P-AP. A second light UV-2 may be transmitted through the window WP and applied to the preliminary adhesive member P-AP. The preliminary adhesive member P-AP may be cured by the second light UV-2, forming the adhesive member AP (FIG. 3).

[0178] 7 is a cross-sectional end view showing a display device according to an embodiment of the present invention. In the following description of the display device shown in FIG. 7, the same content as that described with reference to FIGS. 1 to 6C will not be repeated, and the differences will be mainly described.

[0179] 2 and 3, the display device DD-a shown in Fig. 7 may further include a light control layer PP and an optical adhesive layer AP-a. The display device DD-a of one embodiment may further include a light control layer PP disposed between the adhesive member AP and the window WP, and an optical adhesive layer AP-a disposed between the light control layer PP and the window WP. The light control layer PP may include a polarizer or a color filter layer.

[0180] The optical adhesive layer AP-a may be formed from an embodiment of the resin composition RC (FIGS. 5A and 6A). The optical adhesive layer AP-a containing the polymer derived from the resin composition RC (FIGS. 5A and 6A) may have a storage modulus of 1 MPa or less at a frequency of 1 Hz and a temperature of -20°C. The optical adhesive layer AP-a containing the polymer derived from the resin composition RC (FIGS. 5A and 6A) may have a 180° peel strength of 800 gf / 25 mm or more at 25°C from at least one of a glass substrate and a polymer substrate. The optical adhesive layer AP-a containing the polymer derived from the resin composition RC (FIGS. 5A and 6A) may have a glass transition temperature of 0°C or less. For example, the optical adhesive layer AP-a containing the polymer derived from the resin composition RC (FIGS. 5A and 6A) may have an excellent glass transition temperature of -32°C or less. The optical adhesive layer AP-a containing the polymer derived from the resin composition RC (FIGS. 5A and 6A) may exhibit excellent flexibility and excellent adhesion reliability.

[0181] Fig. 8 is a cross-sectional end view showing a display device according to an embodiment of the present invention. In the following description of the display device according to the embodiment shown in Fig. 8, the same content as that described with reference to Figs. 1 to 7 will not be described again, and the differences will be mainly described.

[0182] 2 and 3, the display device DD-b of an embodiment shown in Fig. 8 may further include a light control layer PP, an optical adhesive layer AP-a, and an interlayer adhesive layer PIB. The display device DD-b of an embodiment shown in Fig. 8 may further include a light control layer PP arranged between the adhesive member AP and the window WP, and an optical adhesive layer AP-a arranged between the light control layer PP and the window WP, like the display device DD-a of an embodiment shown in Fig. 7.

[0183] In the display device DD-b according to one embodiment, an adhesive member AP may be provided between the display panel DP and the input sensing unit TP. That is, the input sensing unit TP may not be disposed directly on the display panel DP, but may be bonded to the display panel DP by the adhesive member AP. For example, the adhesive member AP may be disposed between the sealing layer TFE (FIG. 3) of the display panel DP and the input sensing unit TP.

[0184] An interlayer adhesive layer PIB may be provided below the light control layer PP. The interlayer adhesive layer PIB may be disposed between the input sensing unit TP and the light control layer PP and may be formed of an adhesive material with excellent moisture permeability resistance. For example, the interlayer adhesive layer PIB may be formed of a material containing polyisobutylene. The interlayer adhesive layer PIB may be disposed on the input sensing unit TP and may prevent corrosion of the sensing electrodes of the input sensing unit TP. A display device DD-b according to one embodiment includes an optical adhesive layer AP-a and an adhesive member AP formed from the resin composition RC according to one embodiment, and the display device DD-b including the optical adhesive layer AP-a and the adhesive member AP may exhibit excellent reliability. [Example]

[0185] Hereinafter, a resin composition according to an embodiment of the present invention and an adhesive member made of the resin composition will be described in detail with reference to examples and comparative examples. Note that the examples shown below are merely illustrative examples to aid in understanding the present invention, and the scope of the present invention is not limited thereto.

[0186] 1. Synthesis of (meth)acrylate copolymers The (meth)acrylate copolymers A-1 to A-3 used in the resin compositions of the Examples and Comparative Examples were synthesized by the method described below. The (meth)acrylate copolymers A-1 and A-2 are dendritic polymers of the Examples, and the (meth)acrylate copolymer A-3 is a linear polymer of the Comparative Example.

[0187] <Synthesis of (meth)acrylate copolymer A-1> A round flask equipped with a condenser, a dropping funnel, a nitrogen inlet, and a magnetic stirrer was charged with 60 g of butyl acetate, 16 g of methyl methacrylate (MMA, manufactured by Tokyo Chemical Industry Co., Ltd.), 8.9 g of isobornyl methacrylate (IBXMA, manufactured by Tokyo Chemical Industry Co., Ltd.), 0.2 g of V-601 (dimethyl 2,2'-azobis(methyl 2-propionate), manufactured by FUJIFILM Wako Pure Chemical Co., Ltd.), and 0.6 g of KarenzMT PE1 (pentaerythritol tetrakis(3-mercaptobutyrate), manufactured by Resonac Co., Ltd.). The mixture was reacted at 80 °C for 4 hours under a nitrogen stream to obtain a sample. The cooled sample was then reprecipitated and purified in methanol and dried under vacuum to obtain (meth)acrylate copolymer A-1.

[0188] <Synthesis of (meth)acrylate copolymer A-2> (Meth)acrylate copolymer A-2 was synthesized in the same manner as in the synthesis of (meth)acrylate copolymer A-1, except that 0.6 g of KarenzMT PE1 was changed to 1.6 g of KarenzMT PE1.

[0189] <Synthesis of (meth)acrylate copolymer A-3> (Meth)acrylate copolymer A-3 was synthesized in the same manner as in the synthesis of (meth)acrylate copolymer A-1, except that 0.6 g of KarenzMT PE1 was not added.

[0190] Table 1 below shows the core and branch portions contained in the synthesized (meth)acrylate copolymers A-1 and A-3. In Table 1, "Core" corresponds to the core portion, and "Arm" corresponds to the branch portion. "-*" indicates the position of connection, and "ran" means that the left and right repeating units are randomly connected to each other. (Meth)acrylate copolymer A-2 contains the same core and branch portions as (meth)acrylate copolymer A-1.

[0191] [Table 1]

[0192] Referring to Table 1, it can be seen that (meth)acrylate copolymer A-1 comprises a core portion and a branch portion, and the core portion comprises a monofunctional thiol residue. It can also be seen that (meth)acrylate copolymer A-1 comprises a repeating unit represented by the above-described Chemical Formula 1. As described above, (meth)acrylate copolymer A-1 is a dendritic polymer according to one embodiment.

[0193] In contrast, (meth)acrylate copolymer A-3 is a polymer containing only branches without a core, and does not contain thiol residues. As mentioned above, (meth)acrylate copolymer A-3 is a linear polymer (linear polymer) of the comparative example.

[0194] Table 2 below lists the materials used in synthesizing (meth)acrylate copolymers A-1, A-2, and A-3 and their physical properties. The physical properties were measured by the methods described below.

[0195] <Measurement of molecular weight and molecular weight distribution> Measurements were performed using a gel permeation chromatography (GPC) analyzer HLC-8420GPC manufactured by TOSOH Corporation. A TSKgel SUPER HZM-N was used as the measurement column, and tetrahydrofuran (THF) was used as the measurement solvent. The weight-average molecular weight and molecular weight distribution were obtained in terms of standard polystyrene (PS) from the SEC (Size Exclusion Chromatography) curve detected with a refractive index (RI) detector.

[0196] <Measurement of glass transition temperature> The glass transition was measured using a differential scanning calorimeter (DSC) Photo-DSC 204 Phoenix manufactured by NETZSCH at a heating rate of 10 K / min. The results of the second scan are recorded in Table 2.

[0197] [Table 2]

[0198] Referring to Table 2, (meth)acrylate copolymers A-1 and A-2 have four bonding sites (bond numbers) and are dendritic polymers with a resin-like structure in which four monomer groups branch out from a core. The monomer groups may correspond to the aforementioned branches. (Meth)acrylate copolymer A-3 has zero bonding sites (bond numbers) and corresponds to a linear polymer with a linear structure.

[0199] The (meth)acrylate copolymers A-1 and A-2 have a weight average molecular weight of 1,000 to 50,000, which satisfies the weight average molecular weight of the dendritic polymer according to one embodiment. The (meth)acrylate copolymers A-1 and A-2 have a molecular weight distribution of 1.0 to 3.0, which satisfies the molecular weight distribution of the dendritic polymer according to one embodiment. The (meth)acrylate copolymers A-1 and A-2 have a glass transition temperature of 25°C to 180°C, which satisfies the glass transition temperature of the dendritic polymer according to one embodiment.

[0200] 2. Production and evaluation of resin compositions The resin compositions of the examples and comparative examples were produced using the materials listed in Table 3. The materials listed in Table 3 were weighed out in their respective amounts (g) in a light-shielding glass container and stirred at room temperature for 12 hours on a roll mill.

[0201] <Measurement of shear viscosity of resin composition> In Table 3, the shear viscosity of the resin composition was measured at a temperature of 25°C according to the JIS Z8803 method. The shear viscosity of the resin composition was measured at a speed of 10 rpm using a viscometer TVE-25L (manufactured by TOKI SANGYO Co., LTD.).

[0202] [Table 3]

[0203] <Information on materials in Table 3> 4-HBA: 4-hydroxybutyl acrylate (Osaka Organic Chemical Industry Ltd. product) 2-EHA: 2-ethylhexyl acrylate (product of Toagosei Co., Ltd.) THF-A: Tetrahydrofurfuryl acrylate (Kyoeisha Chemical Co., Ltd. product) EHDG-AT: 2-Ethylhexyl-diglycol acrylate (Kyoeisha Chemical Co., Ltd.) UF-C051: Urethane acrylate (weight average molecular weight 35,000, manufactured by Kyoeisha Chemical Co., Ltd.) UF-C052: Urethane acrylate (weight average molecular weight 10,000, manufactured by Kyoeisha Chemical Co., Ltd.) UN6304: Urethane acrylate (weight average molecular weight 10,000, manufactured by Negami Chemical Industrial Co., Ltd.) Omnirad 819: phenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide (IGM Resins) TPO-L: Ethyl phenyl(2,4,6-trimethylbenzoyl)phosphinate (manufactured by Chitec Technology)

[0204] In Table 3, the resin compositions of Examples 1-1 to 1-6 are resin compositions according to an embodiment and do not contain a solvent. Each of the resin compositions of Examples 1-1 to 1-6 contains a urethane acrylate having a weight-average molecular weight of 10,000 or 35,000, and the urethane acrylate satisfies the weight-average molecular weight range (5,000 to 100,000) of the urethane (meth)acrylate oligomer according to an embodiment.

[0205] Each of the resin compositions of Examples 1-1 to 1-6 contains (meth)acrylate copolymer A-1 or A-2. As described above, (meth)acrylate copolymers A-1 and A-2 correspond to the dendritic polymer of one embodiment. In the resin compositions of Examples 1-1 to 1-4, the weight of (meth)acrylate copolymer A-1 is 0.5 wt% or more and 15 wt% or less, based on the total weight of the resin composition. In the resin compositions of Examples 1-5 and 1-6, the weight of (meth)acrylate copolymer A-2 is 0.5 wt% or more and 15 wt% or less, based on the total weight of the resin composition. In the resin compositions of Examples 1-1 to 1-6, the dendritic polymers, (meth)acrylate copolymers A-1 and A-2, satisfy the weight range of the dendritic polymer of one embodiment.

[0206] The resin composition of Example 1-1 has a total weight of 106 g, and when 106 g is converted to 100 wt%, the weight of the (meth)acrylate copolymer in the resin composition of Example 1-1 is approximately 0.94 wt%. In the same manner, when the total weight of the resin composition of Examples 1-2 to 1-6 is converted to 100 wt%, the weights of the (meth)acrylate copolymer are approximately 2.78 wt%, approximately 4.55 wt%, approximately 8.70 wt%, approximately 4.55 wt%, and approximately 8.70 wt%, respectively.

[0207] The resin compositions of Comparative Examples 1-7 and 1-8 do not contain a dendritic polymer according to an embodiment. The resin composition of Comparative Example 1-7 contains a linear polymer.

[0208] Referring to the shear viscosity in Table 3, it can be seen that the resin compositions of Examples 1-1 to 1-6 have shear viscosities of 5 mPa·s or more and 50 mPa·s or less, measured according to JIS Z8803 at 25°C. The resin compositions of Examples 1-1 to 1-6 are resin compositions according to an embodiment, and contain a monofunctional (meth)acrylate monomer, a urethane (meth)acrylate oligomer having a weight-average molecular weight of 5,000 or more and 100,000 or less, a dendritic polymer, and a photoinitiator. Therefore, it can be seen that the resin compositions according to an embodiment exhibit low viscosity characteristics.

[0209] Referring to the shear viscosity in Table 3, it can be seen that the resin compositions of Comparative Examples 1-8 have shear viscosities exceeding 50 mPa·s at 25°C as measured according to JIS Z8803. It can be seen that the resin compositions of Comparative Examples 1-8 exhibit high shear viscosities because they do not contain a dendritic polymer. As mentioned above, resin compositions with a shear viscosity exceeding 50 mPa·s are difficult to dispense from devices such as nozzles, and are not applied in a uniform amount and / or thickness.

[0210] 3. Manufacturing and evaluation of adhesive materials Table 4 below shows the storage modulus, glass transition temperature, and 180° peel strength of adhesive members made from the resin compositions of Examples and Comparative Examples. The adhesive members of Examples 2-1 to 2-6 were formed from the resin compositions of Examples 1-1 to 1-6, respectively. The adhesive members of Comparative Examples 2-7 and 2-8 were formed from the resin compositions of Examples 1-7 and 1-8, respectively.

[0211] <Measurement of storage modulus and glass transition temperature of adhesive member> A 500 μm thick silicone rubber sheet with an 8 mm inner diameter hole was placed on a release-treated PET film, and approximately 28 μL of the resin composition of the Examples and Comparative Examples was poured into the hole. Next, LED lamps with peak wavelengths of 365 nm and 395 nm were used, each with a total light intensity of 800 mJ / cm. 2 , 400mJ / cm 2Next, a PET film identical to the above PET film was provided, and a glass substrate with a thickness of approximately 1 mm was provided on the PET film. An LED lamp with a peak at a wavelength of 395 nm was used above the glass substrate, and a total amount of light was irradiated to 4000 mJ / cm. 2 A circular sample having a diameter of 8 mm and a thickness of 500 μm was obtained by irradiating the sample with light so that the sample was irradiated ...

[0212] The obtained samples were subjected to viscoelasticity measurements. Measurements were performed using an MCR302 (manufactured by Anton-Paar) at a frequency of 1 Hz, in shear mode, at temperatures from -50 to 80°C, and at a heating rate of 2°C / min. The storage modulus and glass transition temperature at -20°C confirmed by the measurements are recorded in Table 4. The glass transition temperature is the temperature at which the tan δ value reaches its peak, and tan δ is the ratio (G' / G") of the loss modulus (G") to the storage modulus (G').

[0213] <Measurement of 180° peel strength of adhesive materials> The resin compositions of the Examples and Comparative Examples were applied to a 26 mm x 76 mm soda-lime glass (product of Central Glass Co., Ltd.) using a bar coater to a thickness of 50 μm. LED lamps with peaks at wavelengths of 365 nm and 395 nm were used to irradiate the soda-lime with the resin compositions, with a total light intensity of 800 mJ / cm. 2 , 400mJ / cm 2 A 20mm x 150mm PET film (A4360, manufactured by TOYOBO Co., Ltd.) was placed on the irradiated resin composition and bonded under a bonding pressure of 0.15 MPa. After bonding, an LED lamp with a peak wavelength of 395 nm was used to irradiate the PET film with a total light intensity of 4000 J / cm. 2 The sample was obtained by irradiating the sample with light so that the

[0214] The peel strength of the obtained samples was measured using a Universal Testing Machine (Instron Corporation, Model 5965) at a peel angle of 180° at a speed of 300 mm / min under constant temperatures of 25°C and 60°C. The average value for a peel of approximately 50 mm was calculated, and the obtained value was multiplied by 1.25 to record the peel strength for a width of 25 mm in Table 4.

[0215] [Table 4]

[0216] Referring to Table 4, it can be seen that the adhesive members of Examples 2-1 to 2-6 have a storage modulus of 1 MPa or less at a temperature of -20°C and a glass transition temperature of 0°C or less. Specifically, it can be seen that the adhesive members of Examples 2-1 to 2-6 have a glass transition temperature of -32°C or less. It can be seen that the adhesive members of Examples 2-1 to 2-6 have a 180° peel strength of 800 gf / 25 mm or more at a temperature of 25°C. It can be seen that the adhesive members of Examples 2-1 to 2-6 have a 180° peel strength of 500 gf / 25 mm or more and 1200 gf / 25 mm or less at a room temperature of 60°C. The adhesive members of Examples 2-1 to 2-6 are made of a resin composition according to one example. Therefore, it can be seen that an adhesive member made of a resin composition according to one example exhibits excellent flexibility and excellent adhesion reliability.

[0217] Referring to Table 4, the adhesive member of Comparative Example 2-7 has a glass transition temperature of -31°C, which is higher than that of the adhesive members of Examples 2-4 and 2-6. The adhesive members of Comparative Examples 2-7 are made from the resin compositions of Comparative Examples 1-7. As described with reference to Table 3, the resin compositions of Comparative Examples 1-7 contain a linear polymer but not a dendritic polymer. The adhesive members of Examples 2-4 and 2-6 are made from the resin compositions of Examples 1-4 and 1-6. Compared to the resin compositions of Examples 1-4 and 1-6, the resin compositions of Comparative Examples 1-7 contain the same weight (i.e., 10 g) of (meth)acrylate copolymer (i.e., dendritic polymer or linear polymer). The adhesive member of Comparative Example 2-7, which exhibits a relatively high glass transition temperature, is not easily folded and unfolded repeatedly in a relatively low temperature environment. Therefore, adhesive members made from resin compositions containing a linear polymer but not a dendritic polymer are unsuitable for flexible display devices.

[0218] Referring to Table 4, it can be seen that the adhesive members of Comparative Examples 2-8 have a storage modulus of 1 MPa or less at a temperature of -20°C and a glass transition temperature of 0°C or less. However, it can be seen that the adhesive members of Comparative Examples 2-8 have a 180° peel strength of less than 800 gf / 25 mm at a temperature of 25°C. The adhesive members of Comparative Examples 2-8 are formed using the resin compositions of Comparative Examples 1-8, which, as explained with reference to Table 3, do not contain a dendritic polymer. As a result, it can be seen that the adhesive members of Comparative Examples 2-8 exhibit low 180° peel strength.

[0219] A display device according to an embodiment includes an adhesive member disposed between a display panel and a window, and the adhesive member may include a polymer derived from the resin composition according to an embodiment. The adhesive member may be formed by curing the resin composition according to an embodiment.

[0220] The resin composition of one embodiment may include a monofunctional (meth)acrylate monomer, a urethane (meth)acrylate oligomer having a weight average molecular weight of 5,000 to 100,000, a dendritic polymer, and a photoinitiator. As a result, the resin composition of one embodiment may exhibit excellent low viscosity characteristics before curing and excellent flexibility and excellent adhesive reliability after curing. An adhesive member made of the resin composition of one embodiment and a display device including the adhesive member may exhibit excellent reliability.

[0221] Although the present invention has been described above with reference to preferred embodiments, it will be understood by those skilled in the art or those with ordinary knowledge in the art that various modifications and changes may be made to the present invention without departing from the spirit and technical scope of the present invention as set forth in the claims below.

[0222] Therefore, the technical scope of the present invention should not be limited to the contents of the detailed description of the specification, but should be determined by the claims. [Explanation of symbols]

[0223] RC: Resin composition AP: Adhesive material DD: Display device DP: Display panel WP:Window

Claims

1. at least one monofunctional (meth)acrylate monomer; a urethane (meth)acrylate oligomer having a weight average molecular weight of 5,000 or more and 100,000 or less; a dendritic polymer; and at least one photoinitiator comprising a radical polymerization initiator.

2. The resin composition according to claim 1 , wherein the weight of the dendritic polymer is 0.5 wt % to 15 wt % based on the total weight of the resin composition.

3. The resin composition according to claim 1, wherein the glass transition temperature of the dendritic polymer is 25°C or higher and 180°C or lower.

4. 2. The resin composition according to claim 1, wherein the dendritic polymer has a weight average molecular weight of 1,000 or more and 50,000 or less.

5. The resin composition according to claim 1, wherein the dendritic polymer comprises a repeating unit represented by the following chemical formula 1: 【Chemical 1】 Chemical formula 1 In the above Chemical Formula 1, R １ is a hydrogen atom or a methyl group, R ２ is an alkyl group having 1 to 20 carbon atoms.

6. The resin composition according to claim 1 , wherein the dendritic polymer contains a polyfunctional thiol residue.

7. The resin composition according to claim 1, wherein the dendritic polymer has a molecular weight distribution of 1.0 or more and 3.0 or less.

8. The resin composition according to claim 1, which does not contain a solvent.

9. 2. The resin composition according to claim 1, which has a shear viscosity of 5 mPa·s to 50 mPa·s at 25°C measured according to JIS Z8803 method.

10. 2. The resin composition according to claim 1, which has a storage modulus of 1 MPa or less at a frequency of 1 Hz and a temperature of −20° C. after photocuring.

11. 2. The resin composition according to claim 1, wherein after photocuring, the 180° peel strength from at least one of a glass substrate and a polymer substrate at a temperature of 25° C. is 800 gf / 25 mm or more.

12. 2. The resin composition according to claim 1, which has a glass transition temperature of 0°C or lower after photocuring.

13. 2. The resin composition of claim 1, wherein the monofunctional (meth)acrylate monomer comprises at least one of 4-hydroxybutyl acrylate (4-HBA), 2-ethylhexyl acrylate (2-EHA), tetrahydrofurfuryl acrylate (THF-A), and 2-ethylhexyl-diglycol acrylate (EHDG-AT).

14. The resin composition according to claim 1, which is provided by an inkjet printing method or a dispensing method.

15. An adhesive member comprising a polymer derived from a resin composition containing at least one monofunctional (meth)acrylate monomer, a urethane (meth)acrylate oligomer having a weight average molecular weight of 5,000 or more and 100,000 or less, a dendritic polymer, and at least one photoinitiator including a radical polymerization initiator.

16. The adhesive member according to claim 15, which has a storage modulus of 1 MPa or less at a frequency of 1 Hz and a temperature of −20° C.

17. 16. The adhesive member according to claim 15, wherein the adhesive member has a 180° peel strength at 25° C. to at least one of a glass substrate and a polymer substrate of 800 gf / 25 mm or more.

18. The adhesive member according to claim 15, which has a glass transition temperature of 0°C or lower.

19. The adhesive member according to claim 15, wherein the weight of the dendritic polymer is 0.5 wt% to 15 wt% based on the total weight of the resin composition.

20. The adhesive member according to claim 15, wherein the weight average molecular weight of the dendritic polymer is 1,000 or more and 50,000 or less.

21. The adhesive member according to claim 15, wherein the dendritic polymer comprises a repeating unit represented by the following chemical formula 1: 【Chemistry 2】 Chemical formula 1 In the above Chemical Formula 1, R １ is a hydrogen atom or a methyl group, R ２ is an alkyl group having 1 to 20 carbon atoms.

22. The adhesive member according to claim 15 , wherein the dendritic polymer contains a polyfunctional thiol residue.

23. The adhesive member according to claim 15, wherein the dendritic polymer comprises a (meth)acrylate copolymer, and the (meth)acrylate copolymer has a molecular weight distribution of 1.0 or more and 3.0 or less.

24. The adhesive member according to claim 15, wherein the resin composition has a shear viscosity of 5 mPa·s or more and 50 mPa·s or less, measured at 25°C according to JIS Z8803 method.

25. A display panel; a window disposed above the display panel; and an adhesive member disposed between the display panel and the window, the adhesive member comprising a polymer derived from a resin composition comprising at least one monofunctional (meth)acrylate monomer, a urethane (meth)acrylate oligomer having a weight average molecular weight of 5,000 or more and 100,000 or less, a dendritic polymer, and at least one photoinitiator including a radical polymerization initiator.

26. 26. The display device according to claim 25, wherein the adhesive member has a storage modulus of 1 MPa or less at a frequency of 1 Hz and a temperature of −20° C.

27. 26. The display device of claim 25, wherein the adhesive member has a 180° peel strength of 800 gf / 25 mm or more at a temperature of 25° C. with respect to at least one of a glass substrate and a polymer substrate.

28. 26. The display device according to claim 25, wherein the adhesive member has a glass transition temperature of 0° C. or lower.

29. 26. The display device of claim 25, wherein the weight of the dendritic polymer is 0.5 wt % to 15 wt % based on the total weight of the resin composition.

30. 26. The display device according to claim 25, wherein the weight average molecular weight of the dendritic polymer is 1,000 or more and 50,000 or less.

31. 26. The display device of claim 25, wherein the dendritic polymer comprises a repeating unit represented by the following chemical formula 1: 【Chemistry 3】 Chemical formula 1 In the above Chemical Formula 1, R １ is a hydrogen atom or a methyl group, R ２ is an alkyl group having 1 to 20 carbon atoms.

32. The display device according to claim 25 , wherein the dendritic polymer contains a multifunctional thiol residue.

33. 26. The display device of claim 25, wherein the dendritic polymer includes a (meth)acrylate copolymer, and the (meth)acrylate copolymer has a molecular weight distribution of 1.0 or more and 3.0 or less.

34. 26. The display device according to claim 25, wherein the resin composition has a shear viscosity of 5 mPa·s to 50 mPa·s at 25°C as measured by JIS Z8803 method.

35. further comprising an input sensing unit disposed between the display panel and the window; The display device of claim 25, wherein the adhesive member is disposed between the display panel and the input sensing unit or between the input sensing unit and the window.

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