Photosensitive resin composition, photosensitive resin layer using the same, display device, and manufacturing method of photosensitive resin layer

Abstract

A photosensitive resin composition, a photosensitive resin layer manufactured using the photosensitive resin composition, a display device including the photosensitive resin layer, and a method of manufacturing the photosensitive resin layer are provided. The photosensitive resin composition comprises (A) an adhesive resin; (B) a photopolymerizable monomer; (C) a photopolymerization initiator; and (D) a solvent.

Description

Technical Field

[0001] This disclosure relates to a photosensitive resin composition, a photosensitive resin layer using the photosensitive resin composition, a display device, and a method of manufacturing the photosensitive resin layer. [Cross-reference to related applications] []

[0002] This application claims priority and benefits to Korean Patent Application No. 10-2024-0065466, filed on May 20, 2024, with the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference. Prior Technology

[0003] Recently, there has been increasing interest in self-emissive (emitting) organic light-emitting diode (OLED) display panels for use in virtual reality (VR), augmented reality (AR), and mixed reality (MR) devices.

[0004] In micro-OLED display panels with pixels 10 times smaller than those of typical OLED display panels, it is difficult to form red (R) / green (G) / blue (B) emitting layers using traditional fine metal mask (FMM) technology. In other words, if traditional LCD displays are used in VR, AR, and similar devices, the color filters may have excessively large pattern sizes, failing to improve resolution.

[0005] Therefore, OLED-on-Silicon (OLEDos) technology has recently been introduced to achieve high resolutions of 4000 ppi or greater. This technology uses OLEDs deposited on silicon wafers as backlights to pattern color filters. While conventional color filters for LCDs are formed by mounting 100 μm patterns on glass and curing them through an exposure process followed by a post-baking process at 230°C or higher, color filters mounted on OLEDos may not undergo high-temperature processing due to the OLED and should be cured at lower temperatures. Another issue is the low efficiency of light emitted from the OLED when directed to the outside. Therefore, research on transparent, high-refractive-index materials that can be cured at low temperatures continues. Summary of the Invention

[0006] Some exemplary embodiments provide a photosensitive resin composition that is transparent and has a high refractive index, and can be fully cured even at low temperatures.

[0007] Some exemplary embodiments provide a photosensitive resin layer manufactured using a photosensitive resin composition.

[0008] Some exemplary embodiments provide a display device including a photosensitive resin layer.

[0009] Some exemplary embodiments provide a method for manufacturing a photosensitive resin layer.

[0010] Some exemplary embodiments provide a photosensitive resin composition comprising: (A) an adhesive resin; (B) a photopolymerizable monomer; (C) a photopolymerization initiator; and (D) a solvent, wherein the photopolymerizable monomer is represented by chemical formula 1. [Chemical Formula 1]

[0011] In chemical formula 1,

[0012] R1 to R3 are each independently a hydrogen atom or a substituted or unsubstituted C1 to C20 alkyl group.

[0013] L1 to L4 are each independently a substituted or unsubstituted C6 to C20 aryl group.

[0014] L5 is a single bond or a substituted or unsubstituted C6 to C20 aryl group.

[0015] L6 is a substituted or unsubstituted C1 to C20 alkyl group, or a substituted or unsubstituted C6 to C20 aryl group, and

[0016] X is a single bond, *-S-*, or *-NR'-* (where R' is a hydrogen atom or a C1 to C10 alkyl group).

[0017] L1 through L4 can all be the same.

[0018] R1 to R3 can all be the same.

[0019] L5 can be a substituted or unsubstituted C6 to C20 exaryl group, and X can be a single bond or *-S-*.

[0020] L5 can be a single bond, and X can be *-S-* or *-NR'-* (where R' is a hydrogen atom or a C1 to C10 alkyl group).

[0021] L5 can be a single key and X can be a single key.

[0022] The photopolymerizable monomer may be represented by any one of chemical formulas 1-1 to 1-5. [Chemical Formula 1-1] [Chemical Formula 1-2] [Chemical Formulas 1-3] [Chemical Formulas 1-4] [Chemical Formulas 1-5]

[0023] Based on the total amount of the photosensitive resin composition, the photosensitive resin composition may comprise: 10% to 30% by weight of the (A) adhesive resin; 3% to 15% by weight of the (B) photopolymerizable monomer; 0.1% to 5% by weight of the (C) photopolymerization initiator; and the balance being the (D) solvent.

[0024] The photosensitive resin composition may further include malonic acid, 3-amino-1,2-propanediol, silane coupling agent, leveling agent, surfactant, polymerization inhibitor, or a combination thereof as additives.

[0025] The photosensitive resin composition may have a refractive index greater than or equal to 1.66 at 550 nm.

[0026] The photosensitive resin composition may have a transmittance of greater than or equal to 90% at 400 nm to 700 nm.

[0027] Some exemplary embodiments provide a photosensitive resin layer manufactured using the photosensitive resin composition.

[0028] The photosensitive resin layer may be transparent.

[0029] Some exemplary embodiments provide a display device including the photosensitive resin layer.

[0030] The display device may be a micro OLED display device, which includes an OLED substrate located on a silicon wafer and a color filter layer. The color filter layer is located on the OLED substrate and converts white light generated from the OLED substrate into light of multiple colors. The photosensitive resin layer is located on the OLED substrate and the color filter layer, and the color filter layer includes a red color filter, a green color filter, and a blue color filter.

[0031] Some exemplary embodiments provide a method for manufacturing a photosensitive resin layer, the method comprising: coating the photosensitive resin composition; pre-baking at a temperature of 100°C or less after coating; exposing the pre-baked layer to an i-line; and developing the layer.

[0032] Other embodiments of the invention are included in the following detailed description.

[0033] The photosensitive resin composition according to some exemplary embodiments is a transparent photosensitive resin composition that can be cured at a low temperature of 100°C or less, has a high refractive index at 550 nm, and has high transmittance in the visible light range (400 nm to 700 nm). The aforementioned effects can be achieved even at a pre-baking temperature of 100°C or less and by photocuring only (i-line exposure), making the photosensitive resin composition suitable for use as a microlens layer (microlens array) in a micro OLED display device capable of implementing fine patterns. Simple Explanation of the Diagram

[0034] Figure 1 is a schematic diagram illustrating the structure of a micro OLED display device according to some exemplary embodiments. Implementation

[0035] Embodiments of the invention are described in detail below. However, these embodiments are exemplary, and this disclosure is not limited thereto.

[0036] Unless otherwise defined, “alkyl” as used herein refers to C1 to C20 alkyl, “alkenyl” as C2 to C20 alkenyl, “cycloalkenyl” as C3 to C20 cycloalkenyl, “heterocyclic alkenyl” as C3 to C20 heterocyclic alkenyl, “aryl” as C6 to C20 aryl, “arylalkyl” as C6 to C20 arylalkyl, “extrinalkyl” as C1 to C20 exrinalkyl, “extrinaryl” as C6 to C20 exrinaryl, “alkylextrinaryl” as C6 to C20 alkylextrinaryl, “extrinheteroaryl” as C3 to C20 exrinheteroaryl, and “extrinalkoxy” as C1 to C20 exrinalkoxy.

[0037] Unless otherwise specifically defined, “substituted” as used herein means that at least one hydrogen atom of a compound is replaced by a substituent selected from the following: halogen atom (F, Cl, Br or I), hydroxyl, C1 to C20 alkoxy, nitro, cyano, amino, imino, azide, amidine, hydrazine, hydrazine, carbonyl, aminomethyl, thiol, ester, ether, carboxyl or a salt thereof, sulfonic acid or a salt thereof, phosphate or a salt thereof, C1 to C20 alkyl, C2 to C20 alkenyl, C2 to C20 alkynyl, C6 to C20 aryl, C3 to C20 cycloalkyl, C3 to C20 cycloalkenyl, C3 to C20 cycloalkynyl, C2 to C20 heterocyclic alkyl, C2 to C20 heterocyclic alkenyl, C2 to C20 heterocyclic alkynyl, C3 to C20 heterocyclic aryl, or combinations thereof.

[0038] Unless otherwise defined, “heterogeneous” as used herein refers to a chemical formula that includes at least one heteroatom of N, O, S and P.

[0039] Unless otherwise defined, “(meth)acrylate” as used herein refers to both “acrylate” and “methacrylate”, and “(meth)acrylic acid” refers to both “acrylic acid” and “methacrylic acid”.

[0040] Unless otherwise defined, the term “composite” as used herein refers to a blend or copolymer. Additionally, “copolymer” refers to a block copolymer or random copolymer, and “polymer” refers to a block copolymer or random copolymer.

[0041] In the chemical formulas of this specification, unless otherwise specifically defined, hydrogen bonds are indicated where they are not drawn.

[0042] Unless otherwise defined, the asterisk (*) used in this document refers to the connection between the same or different atoms or between chemical formulas.

[0043] The photosensitive resin composition according to some exemplary embodiments comprises: (A) an adhesive resin; (B) a photopolymerizable monomer represented by chemical formula 1; (C) a photopolymerization initiator; and (D) a solvent. [Chemical Formula 1]

[0044] In chemical formula 1,

[0045] R1 to R3 are each independently a hydrogen atom or a substituted or unsubstituted C1 to C20 alkyl group.

[0046] L1 to L4 are each independently a substituted or unsubstituted C6 to C20 aryl group.

[0047] L5 is a single bond or a substituted or unsubstituted C6 to C20 aryl group.

[0048] L6 is a substituted or unsubstituted C1 to C20 alkyl group, or a substituted or unsubstituted C6 to C20 aryl group, and

[0049] X is a single bond, *-S-*, or *-NR'-* (where R' is a hydrogen atom or a C1 to C10 alkyl group).

[0050] Among many types of displays, liquid crystal displays (LCDs) offer advantages such as lightness, thinness, low cost, low operating power consumption, and improved adhesion to integrated circuits, and have been increasingly used in laptops, monitors, and television (TV) screens. An LCD includes a lower substrate and an upper substrate. The lower substrate has a black matrix, color filters, and indium tin oxide (ITO) pixel electrodes formed on it. The upper substrate has an active circuit portion including a liquid crystal layer, thin-film transistors, and capacitor layers, as well as ITO pixel electrodes. Each pixel is formed by sequentially stacking multiple color filters (generally formed by multiple colors, typically the three primary colors of red (R), green (G), and blue (B)) in a predetermined order, thereby forming a color filter in the pixel area. The black matrix layer is disposed on a transparent substrate in a predetermined pattern to form the boundaries between pixels. One method for forming color filters is the pigment dispersion method, which provides a colored film by repeatedly performing a series of processes, such as: coating a photopolymerizable composition containing a colorant onto a transparent substrate including a black matrix; exposing the formed pattern; removing the unexposed portions using a solvent; and thermally curing the composition. The colored photosensitive resin composition used to manufacture color filters according to the pigment dispersion method generally includes an alkali-soluble resin, a photopolymerizable monomer, a photopolymerization initiator, an epoxy resin, a solvent, other additives, and the like, and further includes epoxy resins and similar resins. The pigment dispersion method, possessing the above characteristics, is actively used in the manufacture of liquid crystal displays (LCDs) (e.g., mobile phones, laptops, monitors, and TVs).

[0051] However, when the technology used to manufacture color filters for LCDs is applied to VR and AR devices, which have recently attracted considerable market attention, limitations exist in terms of resolution. To achieve high resolutions of 4000 ppi or higher, OLEDoS (OLED on Silicon) technology is being introduced. This technology uses OLEDs deposited on silicon wafers as backlights and patterns color filters on them. While conventional color filters for LCDs are cured through a post-baking process at temperatures of 230°C or higher, color filters mounted on OLEDoS must be curable at lower temperatures due to the durability of OLED materials. Furthermore, micropatterning is crucial for achieving the desired resolution within small VR and AR devices. This technology can only be cured at low temperatures (100°C), which presents a potential problem of color change due to low chemical resistance. To address this issue, increasing the hardness of the resist is essential.

[0052] Displays like OLEDs generally suffer from inefficiency, meaning that the light they produce leaks out. As a solution to this problem, techniques are known to use high-refractive-index layers or patterns to control the refractive index difference, which is one of the causes of light loss when light leaks out.

[0053] As an attempt to enable polymer compounds to have high functionality, the development of polyimide polymer materials containing sulfur atoms is mainly aimed at ensuring a high refractive index (>1.60). However, polyimide materials have the property of absorbing light in the wavelength range of about 400 nm, and are therefore unsuitable for use in microlenses that receive light in the visible light region (400 nm to 700 nm).

[0054] This invention does not relate to color photoresists traditionally used in the manufacture of color filters, but rather to microlenses applied to micro-OLED display devices, wherein the microlenses maintain a high refractive index of greater than or equal to 1.66, for example greater than or equal to 1.67, for example greater than or equal to 1.68, for example greater than or equal to 1.69, or for example greater than or equal to 1.7 at 550 nm, but still have a high transmittance of greater than or equal to 90% or for example greater than or equal to 95% in the visible light region, and are therefore very suitable for receiving light.

[0055] Each component will be described in detail below. (A) Adhesive resin

[0056] The adhesive resin may include acrylic adhesive resin.

[0057] Acrylic adhesive resin is a copolymer of a first olefinic unsaturated monomer and a second olefinic unsaturated monomer that can be copolymerized therewith, and is a resin containing one or more repeating acrylic units.

[0058] The first olefinic unsaturated monomer may be an olefinic unsaturated monomer containing at least one carboxyl group, and specific examples of said monomer include acrylic acid, methacrylic acid, maleic acid, itaconic acid, fumaric acid or combinations thereof.

[0059] The first olefinic unsaturated monomer may be contained in an amount of 5% to 50% by weight, for example, 10% to 40% by weight, based on the total amount of the acrylic adhesive resin.

[0060] Examples of second-ene unsaturated monomers may include: aromatic vinyl compounds, such as styrene, α-methylstyrene, vinyltoluene, vinyl benzyl methyl ether, and the like; unsaturated carboxylic acid ester compounds, such as methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, benzyl (meth)acrylate, cyclohexyl (meth)acrylate, phenyl (meth)acrylate, and the like; unsaturated carboxylic acid aminoalkyl ester compounds, such as 2-aminoethyl (meth)acrylate, 2-dimethylaminoethyl (meth)acrylate, and the like; carboxylic acid vinyl ester compounds, such as vinyl acetate, vinyl benzoate, and the like; unsaturated carboxylic acid glycidyl ester compounds, such as glycidyl (meth)acrylate and the like; cyanide compounds, such as (meth)acrylonitrile and the like; unsaturated amide compounds, such as (meth)acrylamide and the like; etc., and said compounds may be used alone or in mixtures of both or more thereof.

[0061] Specific examples of acrylic adhesive resins may be (meth)acrylic acid / benzyl methacrylate copolymers, (meth)acrylic acid / benzyl methacrylate / styrene copolymers, (meth)acrylic acid / benzyl methacrylate / 2-hydroxyethyl methacrylate copolymers, (meth)acrylic acid / benzyl methacrylate / styrene / 2-hydroxyethyl methacrylate copolymers, and the like, but are not limited thereto, and said acrylic resins may be used alone or in mixtures of two or more of them.

[0062] Acrylic adhesive resins can have a weight-average molecular weight of 3,000 g / mol to 20,000 g / mol and a double bond equivalent weight greater than or equal to 340 g / mol. If the weight-average molecular weight and double bond equivalent weight of the acrylic adhesive resin are within the above ranges, it has excellent patterning properties, and the film produced can have excellent mechanical and thermal properties.

[0063] Adhesive resins may include epoxy adhesive resins.

[0064] The heat resistance of the adhesive resin can be improved by also including epoxy adhesive resins. Epoxy adhesive resins may be, for example, phenolic epoxy resins, tetramethylbiphenyl epoxy resins, bisphenol A epoxy resins, bisphenol F epoxy resins, alicyclic epoxy resins, or combinations thereof, but are not limited thereto.

[0065] In addition, adhesive resins, including epoxy-based adhesive resins, ensure the dispersion stability of colorants (such as pigments) (which will be discussed later) and help to form pixels with the desired resolution during the development process.

[0066] The epoxy adhesive resin may be included in the total amount of the adhesive resin, ranging from 1% to 10% by weight, for example, from 5% to 10% by weight. Including epoxy adhesive resin within this range can significantly improve film residue and chemical resistance.

[0067] The epoxy equivalent weight of the epoxy adhesive resin can be from 150 g / eq to 200 g / eq. If the adhesive resin contains an epoxy adhesive resin with an epoxy equivalent weight within the above range, it has a beneficial effect on improving the curing degree of the formed pattern and fixing the colorant therein to form the patterned structure.

[0068] In addition, the binder resin may be included in an amount of 10% to 30% by weight, for example, 10% to 25% by weight, based on the total amount of the photosensitive resin composition. If the binder resin is included within the above range, excellent sensitivity, developability, resolution, and linearity of the pattern can be obtained. (B) Photopolymerizable monomers

[0069] The photopolymerizable monomer in the photosensitive resin composition according to some exemplary embodiments may be a single compound or a mixture of two different types of compounds.

[0070] For example, the photopolymerizable monomer can be a trifunctional ester of (meth)acrylic acid having at least one olefinic unsaturated double bond, and specifically, the photopolymerizable monomer can be represented by chemical formula 1.

[0071] Since the photopolymerizable monomer is represented by chemical formula 1, it can form patterns with excellent heat resistance, light resistance and chemical resistance by causing full polymerization during exposure in the patterning process, and it can also have a high refractive index at 550 nm and a high transmittance in the visible light region.

[0072] For example, L1 to L4 can all be the same, and for example, L1 to L4 can all be substituted or unsubstituted C6 aryl groups (e.g., arylphenyl groups).

[0073] For example, R1 to R3 can all be the same, and for example, R1 to R3 can all be methyl or hydrogen atoms.

[0074] For example, L5 can be a substituted or unsubstituted C6 to C20 exaryl group, and X can be a single bond or *-S-*.

[0075] For example, L5 can be a single bond, and X can be *-S-* or *-NR'-* (where R' can be a hydrogen atom or a C1 to C10 alkyl group).

[0076] For example, L5 can be a single key, and at the same time, X can also be a single key.

[0077] For example, photopolymerizable monomers can be represented by any of the chemical formulas 1-1 to 1-5, but are not limited to these. [Chemical Formula 1-1] [Chemical Formula 1-2] [Chemical Formulas 1-3] [Chemical Formulas 1-4] [Chemical Formulas 1-5]

[0078] The photosensitive resin composition according to some exemplary embodiments may also include photopolymerizable monomers with different structures and photopolymerizable monomers represented by chemical formula 1.

[0079] Specific examples of photopolymerizable monomers having a structure different from that of Formula 1 include: ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, bisphenol A di(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra ... Hexamethacrylate, dipentaerythritol dimethacrylate, dipentaerythritol trimethacrylate, dipentaerythritol pentamethacrylate, dipentaerythritol hexamethacrylate, bisphenol A epoxy methacrylate, ethylene glycol monomethyl ether methacrylate, trimethylolpropane trimethacrylate, trimethacryloxyethyl phosphate, phenolic epoxy methacrylate, ethoxylated diphenylfluorene diacrylate, ethoxylated naphthyl diacrylate, ethoxylated sulfur diacrylate, and the like.

[0080] Commercially available examples of photopolymerizable monomers having structures different from those of Formula 1 are as follows. Examples of monofunctional esters of (meth)acrylic acid may include: Aronix M-101®, M-111®, M-114® (Toagosei Chemistry Industry Co., Ltd.); KAYARAD TC-110S®, TC-120S® (Nippon Kayaku Co., Ltd.); V-158®, V-2311® (Osaka Organic Chemical Ind., Ltd.) and the like. Examples of difunctional (meth)acrylates may include: Anix M-210®, M-240®, M-6200® (Dong-A Synthetic Chemicals Co., Ltd.), Cayalard HDDA®, HX-220®, R-604® (Nippon Kayaku Co., Ltd.), V-260®, V-312®, V-335 HP® (Osaka Organic Chemicals Co., Ltd.), BPF-022, BPF-022B, BPF-022L, BPF-022G, BPF-102, BPF-152, BPF-202, BPF-302, BN-042, BN-102, TBP-042, TBP-102 (Hannong Chemicals Inc.) and the like. Examples of trifunctional esters of (meth)acrylic acid may include: Anix M-309®, M-400®, M-405®, M-450®, M-710®, M-8030®, M-8060® (Toa Synthetic Chemicals Co., Ltd.), Cayalard TMPTA®, DPCA-20®, DPCA-30®, DPCA-60®, DPCA-120® (Nippon Kayaku Co., Ltd.), V-295®, V-300®, V-360®, V-GPT®, V-3PA®, V-400® (Osaka Yuki Kayaku Kogyo Co. Ltd.) and the like. These products may be used alone or in mixtures of both or more of them.

[0081] Photopolymerizable monomers can be treated with acid anhydrides to improve their developability.

[0082] For example, the photopolymerizable monomer may be included in an amount of 3% to 15% by weight, or for example, 5% to 10% by weight, based on the total amount of the photosensitive resin composition. For example, the photopolymerizable monomer may be included in an amount of 20% to 60% by weight, or for example, 30% to 50% by weight, based on the total amount of solids constituting the photosensitive resin composition. When the photopolymerizable monomer is included within these ranges, it is sufficiently cured during exposure in the patterning process, exhibiting excellent reliability and improving the developability of alkaline developers. (C) Photopolymerization initiator

[0083] The photosensitive resin composition according to some exemplary embodiments includes a photopolymerization initiator. The photopolymerization initiator may include acetophenone compounds, benzophenone compounds, thioxanone compounds, benzoin compounds, triazine compounds, oxime compounds, and similar compounds.

[0084] Examples of acetophenone compounds include 2,2'-diethoxyacetophenone, 2,2'-dibutoxyacetophenone, 2-hydroxy-2-methylacetophenone, p-tert-butyltrichloroacetophenone, p-tert-butyldichloroacetophenone, 4-chloroacetophenone, 2,2'-dichloro-4-phenoxyacetophenone, 2-methyl-1-(4-(methylthio)phenyl)-2-morpholinoprop-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-but-1-one, and the like.

[0085] Examples of benzophenone compounds include benzophenone, benzoyl benzoate, benzoyl methyl benzoate, 4-phenylbenzophenone, hydroxybenzophenone, benzoyl acrylate, 4,4'-bis(dimethylamino)benzophenone, 4,4'-bis(diethylamino)benzophenone, 4,4'-dimethylaminobenzophenone, 4,4'-dichlorobenzophenone, 3,3'-dimethyl-2-methoxybenzophenone, and the like.

[0086] Examples of thioxanthone compounds include thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone and the like.

[0087] Examples of benzoin compounds include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzyl dimethyl ketal, and the like.

[0088] Examples of triazine compounds include 2,4,6-trichloro-s-triazine, 2-phenyl-4,6-bis(trichloromethyl)-s-triazine, 2-(3',4'-dimethoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4'-methoxynaphthyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(p-methoxyphenyl)-4,6-bis(trichloromethyl)-s-triazine, and 2-(p-tolyl)-4,6-bis(trichloromethyl)-s- Triazine, 2-biphenyl-4,6-bis(trichloromethyl)-s-triazine, bis(trichloromethyl)-6-styryl-s-triazine, 2-(naphthol-1-yl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4-methoxynaphthol-1-yl)-4,6-bis(trichloromethyl)-s-triazine, 2-4-bis(trichloromethyl)-6-piperyl-s-triazine, 2-4-bis(trichloromethyl)-6-(4-methoxystyryl)-s-triazine and the like.

[0089] Examples of oxime compounds include O-acetylgime compounds, 2-(O-benzoacetylgime)-1-[4-(phenylthio)phenyl]-1,2-octanedione, and 1-(O-acetylgime)-1-[9-ethyl-6-(2-methylbenzoacetylgime)-9H-carbazole-3-yl]ethenone. Specific examples of oxime compounds include 1,2-octanedione, 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-yl-phenyl)-but-1-one, 1-(4-phenylthiophenyl)-1,2-dione-2-oxime-O-benzoate, 1-(4-phenylthiophenyl)-octane-1,2-dione-2-oxime-O-benzoate, 1-(4-phenylthiophenyl)-octane-1-one-oxime-O-acetate, 1-(4-phenylthiophenyl)-but-1-one-oxime-O-acetate, and the like.

[0090] In addition to the compounds mentioned above, photopolymerization initiators can also be used with, for example, carbazole compounds, diketone compounds, strontium borate compounds, diazo compounds, imidazole compounds, biimidazole compounds and the like.

[0091] For example, based on the total amount of the photosensitive resin composition, a photopolymerization initiator may be included in an amount from 0.1 wt% to 5 wt%, for example, from 0.5 wt% to 3 wt%. For example, based on the total amount of solids constituting the photosensitive resin composition, a photopolymerization initiator may be included in an amount from 1 wt% to 5 wt%, for example, from 1.5 wt% to 3 wt%. When a photopolymerization initiator is included within the above range, sufficient photopolymerization occurs during exposure in the patterning process used to manufacture microlenses, resulting in excellent sensitivity and improved transmittance. (D) Solvent

[0092] The solvent can be a material that is compatible with polymer resins, photopolymerizable monomers, and photopolymerization initiators but does not react with them.

[0093] Examples of solvents may include: alcohols, such as methanol, ethanol, and the like; ethers, such as dichloroethyl ether, n-butyl ether, diisopentyl ether, methyl phenyl ether, tetrahydrofuran, and the like; glycol ethers, such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol dimethyl ether, and the like; celux acetate, such as methyl celux acetate, ethyl celux acetate, diethyl celux acetate, and the like; carbitol, such as methyl ethyl carbitol, diethyl carbitol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, diethylene glycol diethyl ether, and the like; propylene glycol alkyl ether acetates, Examples include propylene glycol methyl ether acetate, propylene glycol propyl ether acetate, and the like; aromatic hydrocarbons, such as toluene, xylene, and the like; ketones, such as methyl ethyl ketone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone, methyl-n-propyl ketone, methyl-n-butyl ketone, methyl-n-pentanone, 2-heptanone, and the like; saturated aliphatic monocarboxylic acid alkyl esters, such as ethyl acetate, n-butyl acetate, isobutyl acetate, and the like; lactic acid esters, such as methyl lactate, ethyl lactate, and the like; alkyl oxyacetic acid esters, such as methyl oxyacetate, ethyl oxyacetate, butyl oxyacetate, and the like; alkyl alkoxyacetic acid esters, such as methoxy... Methyl methoxyacetate, ethyl methoxyacetate, butyl methoxyacetate, methyl ethoxyacetate, ethyl ethoxyacetate and the like; alkyl 3-oxypropionic acid esters, such as methyl 3-oxypropionic acid, ethyl 3-oxypropionic acid and the like; alkyl 3-alkoxypropionic acid esters, such as methyl 3-methoxypropionic acid, ethyl 3-methoxypropionic acid, ethyl 3-ethoxypropionic acid, methyl 3-ethoxypropionic acid and the like; alkyl 2-oxypropionic acid esters, such as methyl 2-oxypropionic acid, ethyl 2-oxypropionic acid, propyl 2-oxypropionic acid and the like; alkyl 2-alkoxypropionic acid esters, such as methyl 2-methoxypropionic acid, alkyl 2-methoxypropionic acid... Ethyl esters, ethyl 2-ethoxypropionate, methyl 2-ethoxypropionate and the like; 2-oxy-2-methylpropionates, such as methyl 2-oxy-2-methylpropionate, ethyl 2-oxy-2-methylpropionate and the like; monooxymonocarboxylic acid alkyl esters of alkyl 2-alkoxy-2-methylpropionates, such as methyl 2-methoxy-2-methylpropionate, ethyl 2-ethoxy-2-methylpropionate and the like; esters, such as 2-hydroxyethylpropionate, 2-hydroxy-2-methylethylpropionate, hydroxyethyl acetate, 2-hydroxy-3-methylethylbutyrate and the like; keto esters, such as ethyl pyruvate and the like. Alternatively, high-boiling-point solvents may be used, such as N-methylformamide, N,N-dimethylformamide, N-methylformaniline, N-methylacetamide, N,N-dimethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide, benzyl ethyl ether, dihexyl ether, acetoacetone, isophorone, hexanoic acid, octanoic acid, 1-octanol, 1-nonanol, benzyl alcohol, benzyl acetate, ethyl benzoate, diethyl oxalate, diethyl maleate, γ-butyrolactone, ethyl carbonate, propyl carbonate, phenylcelusyl acetate, and the like.

[0094] Considering miscibility and reactivity, the following can be used: glycol ethers, such as ethylene glycol monoethyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol ethyl methyl ether and the like; ethylene glycol alkyl ether acetates, such as ethyl celusone acetate and the like; esters, such as 2-hydroxyethyl propionate and the like; carbitol, such as diethylene glycol monomethyl ether and the like; propylene glycol alkyl ether acetates, such as propylene glycol monomethyl ether acetate, propylene glycol propyl ether acetate and the like.

[0095] The total amount of the photosensitive resin composition may include, for example, 50% to 90% by weight, 60% to 80% by weight, or 70% to 80% by weight of solvent. If solvent is included within the range, the photosensitive resin composition may have a suitable viscosity, and thus processability is improved during the production of the photosensitive resin layer (specifically, the microlens). (E) Other additives

[0096] Additionally, the photosensitive resin composition may also contain additives such as malonic acid, 3-amino-1,2-propanediol, silane coupling agents, leveling agents, surfactants, polymerization inhibitors, or combinations thereof.

[0097] Silicon-based coupling agents may have reactive substituents (e.g., vinyl, carboxyl, methacryloxy, isocyanate, or epoxy groups) to improve adhesion to the substrate. However, if a silicon-based coupling agent is used, since the photosensitive resin compositions according to some exemplary embodiments are even colorant-free compositions, i.e., transparent photosensitive resin compositions, the effect of improving adhesion to the color filter may not be achieved unless the refractive index of the polymer resin at 550 nm is controlled as described above.

[0098] Examples of silane coupling agents may include trimethoxysilylbenzoic acid, γ-methacryloxypropyltrimethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, γ-isocyanate propyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and the like. These silane coupling agents may be used alone or in mixtures of both or more thereof.

[0099] Based on 100 parts by weight of the photosensitive resin composition, a silane coupling agent may be included in an amount from 0.01 parts by weight to 10 parts by weight. If a silane coupling agent is included within the above range, adhesion, storage capacity, and similar properties are improved.

[0100] Additionally, depending on the requirements, the photosensitive resin composition may also include surfactants, such as fluorinated surfactants and / or silicone surfactants, to improve coating properties and prevent defect formation.

[0101] Examples of fluorinated surfactants include commercial fluorinated surfactants such as BM-1000®, BM-1100® and similar products from BM Chemie Inc.; MEGAFACE F 142D®, MEGAFACE F 172®, MEGAFACE F 173®, MEGAFACE F 183®, MEGAFACE F 554® and similar products from Dainippon Ink Kagaku Kogyo Co., Ltd.; FULORAD FC-135®, FULORAD FC-170C®, FULORAD FC-430®, FULORAD FC-431® and similar products from Sumitomo 3M Co., Ltd.; and FULORAD FC-135®, FULORAD FC-170C®, FULORAD FC-430®, FULORAD FC-431® and similar products from Asahi Glass Co., Ltd. SURFLON S-112®, SURFLON S-113®, SURFLON S-131®, SURFLON S-141®, SURFLON S-145® and similar products from Toray Silicone Co., Ltd.; and SH-28PA®, SH-190®, SH-193®, SZ-6032®, SF-8428® and similar products from Toray Silicone Co., Ltd.

[0102] The surfactant may be a commercial silicone surfactant, such as BYK-307, BYK-333, BYK-361N, BYK-051, BYK-052, BYK-053, BYK-067A, BYK-077, BYK-301, BYK-322, BYK-325 and the like from BYK Chem.

[0103] Based on 100 parts by weight of the photosensitive resin composition, a surfactant may be used in amounts from 0.001 parts by weight to 5 parts by weight. The inclusion of a surfactant within this range ensures uniform coating, prevents staining, and improves wettability on indium zinc oxide (IZO) substrates or glass substrates.

[0104] Polymerization inhibitors may include, but are not limited to, catechol compounds. Since the photosensitive resin compositions according to some exemplary embodiments also include catechol compounds, room-temperature crosslinking can be prevented during exposure after coating the photosensitive resin composition.

[0105] For example, catechol compounds may include catechol, tert-butylcatechol, 4-methoxyphenol, pyrogallol, 2,6-di-tert-butyl-4-methylphenol, 2-naphthol, and tris(N-hydroxy-N-nitrosophenylaminato-O,O')aluminum, but are not limited to these.

[0106] Catechol compounds can be used in dispersion form, and the polymerization inhibitor in dispersion form can be included in an amount from 0.001% to 3% by weight, for example, from 0.01% to 1% by weight, based on the total amount of the photosensitive resin composition. If the polymerization inhibitor is within the above range, the aging problem at room temperature can be solved, and sensitivity degradation and surface peeling can be prevented.

[0107] In addition, the photosensitive resin composition may include a predetermined amount of other additives (such as stabilizers and similar additives) unless the additives would degrade the properties of the photosensitive resin composition.

[0108] The photosensitive resin composition according to some exemplary embodiments may be positive or negative, but should be negative in order to completely remove residues in the exposed areas of the pattern after exposure and development of the composition having light-blocking properties.

[0109] On the other hand, photosensitive resin compositions comprising photopolymerizable monomers represented by Chemical Formula 1, according to some exemplary embodiments, may have a refractive index greater than or equal to 1.66 (at 550 nm), for example greater than or equal to 1.62 and less than or equal to 1.9 (at 550 nm). Additionally, photosensitive resin compositions comprising photopolymerizable monomers represented by Chemical Formula 1, according to some exemplary embodiments, may have a transmittance greater than or equal to 90%, for example greater than or equal to 95%, for example greater than or equal to 96%, or for example greater than or equal to 97% in the visible light region (400 nm to 700 nm). Photosensitive resin compositions comprising photopolymerizable monomers represented by Chemical Formula 1 (with the refractive index at 550 nm and transmittance in the visible light region controlled as described above) can significantly reduce light loss when white light leaks from the OLED substrate, and further advantageously contribute to improved developability and fine patterning capabilities. Due to these properties, photosensitive resin compositions according to some exemplary embodiments are very suitable as microlens materials for OLEDOS.

[0110] Some exemplary embodiments provide photosensitive resin layers manufactured by low-temperature curing, exposure, and development of the above-described photosensitive resin composition. The difference compared to conventional LCD or semiconductor manufacturing processes is that a post-curing (post-baking) process is unnecessary.

[0111] The method for manufacturing the photosensitive resin layer is as follows.

[0112] (1) Coating and film formation (low-temperature curing)

[0113] A photosensitive resin composition is coated onto a pre-treated substrate (e.g., a silicon wafer or similar substrate) to a desired thickness using spin coating, slot coating, roller coating, screen printing, applicator method, or similar methods. The substrate is then heated at 100°C for 1 to 10 minutes to remove the solvent and form the photosensitive resin layer. This step can improve image quality, etc.

[0114] (2) Exposure

[0115] After setting up a mask to form the necessary pattern on the obtained photosensitive resin layer, exposure is performed by irradiating i-line photochemical rays. As the light source for irradiation, low-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, metal halide lamps, argon lasers, etc., can be used, and in some cases, X-rays, electron beams, and similar light sources can be used.

[0116] When using a high-pressure mercury lamp, the exposure process uses a light dose of, for example, 500 mJ / cm² or less (using a 365 nm sensor). However, the light dose can vary depending on the type of each component, their combination ratio, and the dry film thickness. This step allows for fine-tuning of the pixel size, thereby enabling high resolution.

[0117] (3) Development

[0118] In the development method, after the exposure step, an alkaline aqueous solution is used as a developer to dissolve and remove unwanted parts, leaving only the exposed parts to form a pattern. This step creates an outline for high resolution and ensures color uniformity for improved sharpness.

[0119] Some exemplary embodiments provide a display device including a photosensitive resin layer.

[0120] The display device may be a micro organic light-emitting diode (OLED) display device.

[0121] A micro-organic light-emitting diode (OLED) display device may include an OLED substrate deposited on a silicon wafer and a color filter layer. The color filter layer is located on the OLED substrate and converts white light generated from the OLED substrate into light of various colors, including a red color filter, a green color filter, and a blue color filter. Furthermore, a photosensitive resin layer, i.e., a microlens layer, is located on the OLED substrate and the color filter layer. In other words, the microlens layer may surround the color filter layer on the OLED substrate.

[0122] For example, a micro-organic light-emitting diode (OLED) display device includes an OLED substrate on a silicon wafer, an inorganic layer stacked on the OLED substrate, and a color filter layer stacked on the inorganic layer that converts white light generated from the OLED substrate into various colors of light. The color filter layer may include a red color filter, a green color filter, and a blue color filter. Furthermore, a photosensitive resin layer, i.e., a microlens layer, is located on the inorganic layer and the color filter layer. In other words, the microlens layer may surround the color filter layer on the inorganic layer.

[0123] For example, a micro-organic light-emitting diode (OLED) display device may include an OLED substrate 200 deposited on a silicon wafer 100, an inorganic layer 300 stacked on the OLED substrate 200, an adhesive protective layer 400 stacked on the inorganic layer 300, and a color filter layer stacked on the adhesive protective layer 400 that converts white light generated from the OLED substrate 200 into light of various colors, wherein the color filter layer includes a red color filter R, a green color filter G, and a blue color filter B. Furthermore, the adhesive protective layer 400, i.e., a microlens layer 500, is located on the adhesive protective layer 400 and the color filter layer. That is, the microlens layer 500 may surround the color filter layer on the adhesive protective layer 400.

[0124] Conventionally, OLED substrates in which OLEDs are deposited on glass or polyimide substrates are used. However, according to some exemplary embodiments, micro-OLED display devices may be more advantageous in implementing microdisplays because the OLEDs are deposited on silicon wafers. These microdisplays are attracting considerable attention as next-generation displays and are expected to be used in devices such as MR. In fact, Apple, Meta, and LG Display have all entered or announced their entry into the next-generation MR device market.

[0125] By depositing white OLEDs (WOLEDs) on highly integrated silicon wafers, micro OLED display devices with the above structure can be driven based on pixels, and the transmission wavelength can be easily controlled by color filter layers patterned with a resolution of less than or equal to 3 μm, thereby enabling high color reproduction and ensuring high resolution.

[0126] For example, the adhesive protective layer can have a thickness of less than or equal to 1 μm. In this case, the effects mentioned above, namely improved adhesion to the color filter and improved residue properties, can be further maximized.

[0127] For example, the color filter layer can have a thickness of 1.1 μm to 1.6 μm.

[0128] If the thickness of the color filter layer is controlled as described above, it may be more advantageous to implement a micro OLED display device.

[0129] For example, the inorganic layer can have a thickness of less than or equal to 2 μm. Even with WOLED, since light does not always diffuse in a direction perpendicular to the OLED substrate, color mixing of red, green, and blue inevitably occurs. Therefore, in the past, inorganic layers were deposited on the OLED substrate to prevent this color mixing. However, since color mixing cannot be completely prevented even by depositing an inorganic layer, in some exemplary embodiments, slight light leakage can be prevented by thinning the inorganic layer, for example, controlling the thickness of the inorganic layer to less than or equal to 2 μm.

[0130] Finally, as described above, the photosensitive resin composition according to some exemplary embodiments enables the curing layer to be produced by curing at low temperature (100°C) only during pre-baking and i-line photocuring, and there is necessarily a huge difference in the achievable resolution compared to conventional display devices.

[0131] Preferred embodiments of the present invention will be described below. However, the following examples are merely preferred embodiments of the present invention, and the present invention is not limited to these examples. [(Example)] [Preparation Example] [1] [Based on chemical formula] [1-1] [Synthesis of the represented compound] (Reaction Scheme 1)

[0132] Compound 1a (10.0 mmol) was dissolved in 20 mL of tetrahydrofuran (THF) to obtain a solution. After cooling the solution to 0 °C, another solution prepared by dissolving compound 1b (22.0 mmol) in THF was added dropwise. After the dropwise addition, the resulting mixture was stirred overnight at room temperature. When the reaction was complete, 1 N HCl aqueous solution was added, and then extracted with ethyl acetate. The resulting organic layer was anhydrous, concentrated under reduced pressure, and then purified by column chromatography (eluent: n-hexane / ethyl acetate (EtOAc)) to obtain compound 1c. (Reaction Scheme 2)

[0133] Compound 1c (10.0 mmol) and compound 1d (12.0 mmol) were added to 80.0 mL of toluene / H2O (v / v = 5 / 1) with Pd(PPh3)4 (0.30 mmol) and potassium carbonate (K2CO3, 50.0 mmol), and the reaction was carried out overnight under reflux. After cooling to room temperature, the organic layer was separated and then concentrated under reduced pressure to remove the solvent. Subsequently, methanol was added to the reaction mixture to form a precipitate, which was separated by filtration under reduced pressure and then washed with distilled water. Compound 1e was obtained by drying in a vacuum oven overnight. (Reaction Scheme 3)

[0134] Compound 1e (10.0 mmol) and compound 1f (60.0 mmol) were added to 35.0 mL of N,N-dimethylformamide (DMF) with potassium carbonate (K₂CO₃, 60.0 mmol) and reacted overnight under reflux. After cooling to room temperature, the result was added to 100 mL of 1 N HCl aqueous solution to form a precipitate. The solid was separated by filtration under reduced pressure, washed with distilled water, and dried overnight in a vacuum oven. Subsequently, purification by column chromatography (eluent: n-hexane / EtOAc) yielded 1 g of compound. (Reaction Scheme 4) Chemical Formula 1

[0135] 1 g (5.00 mmol) of compound and 30.0 mmol of triethylamine were dissolved in 30.0 mL of tetrahydrofuran (THF), and after cooling the solution to 0 °C, another solution prepared by dissolving 1 h (22.5 mmol) of compound in 10.0 mL of THF was slowly added. The reaction mixture was stirred overnight at room temperature, and a saturated aqueous solution of sodium bicarbonate was added. The resulting solution was diluted with distilled water and then extracted with dichloromethane (DCM). The resulting organic layer was passed through MgSO4, concentrated under reduced pressure, and purified by column chromatography (eluent: DCM) to obtain the compound represented by formula 1.

[0136] The analytical results of the compound represented by chemical formula 1 are as follows.

[0137] Matrix-assisted laser desorption / ionization-time-of-flight mass spectrometry (MALDI-TOF MS): 844.15 m / z [Preparation Example] [2] [Based on chemical formula] [2] [Synthesis of the represented compound] (Reaction Scheme 5)

[0138] Compound 1c (5.00 mmol) and N,N-diisopropylethylamine (DIPEA, 7.50 mmol) were dissolved in 15.0 mL of tetrahydrofuran (THF), and compound 2a (6.00 mmol) was added to the solution. The resulting mixture was stirred overnight at room temperature. After removing the solvent by concentration under reduced pressure, compound 2b was obtained by purification by column chromatography (elution: n-hexane / EtOAc). (Reaction Scheme 6)

[0139] Compound 2b (10.0 mmol) and compound 1f (40.0 mmol) were added to 35.0 mL of N,N-dimethylformamide (DMF) with potassium carbonate (K₂CO₃, 40.0 mmol) and reacted overnight under reflux. After cooling to room temperature, the result was added to 100 mL of 1 N HCl aqueous solution to form a precipitate. The solid was separated by filtration under reduced pressure, washed with distilled water, and dried overnight in a vacuum oven. Compound 2c was obtained by purification by column chromatography (eluent: n-hexane / EtOAc). (Reaction Scheme 7) Chemical formula 2

[0140] Except for using compound 2c instead of compound 1g, the compound represented by chemical formula 2 was synthesized in the same manner as the material corresponding to chemical formula 1.

[0141] The analytical results of the compound represented by chemical formula 2 are as follows.

[0142] MALDI-TOF MS: 751.16 m / z [Preparation Example] [3] [Based on chemical formula] [3] [Synthesis of the represented compound] (Reaction Scheme 8)

[0143] Compound 3b was synthesized in the same manner as compound 1e, except that compound 3a was used instead of compound 1d. (Reaction Scheme 9)

[0144] Compound 3c was synthesized in the same manner as compound 2c, except that compound 3b was used instead of compound 2b. (Reaction Scheme 10) Chemical formula 3

[0145] Except for using compound 3c instead of compound 1g, the compound represented by chemical formula 3 was synthesized in the same manner as the material corresponding to chemical formula 1.

[0146] The analytical results for the compound represented by chemical formula 3 are as follows.

[0147] MALDI-TOF MS: 736.15 m / z [Preparation Example] [4] [Based on chemical formula] [4] [Synthesis of the represented compound] (Reaction Scheme 11)

[0148] Compound 4b was synthesized in the same manner as compound 2b, except that compound 4a was used instead of compound 2a. (Reaction Scheme 12)

[0149] Compound 4c was synthesized in the same manner as compound 2c, except that compound 4b was used instead of compound 2b. (Reaction Scheme 13) Chemical Formula 4

[0150] Except for using compound 4c instead of compound 1g, the compound represented by chemical formula 4 was synthesized in the same manner as the material corresponding to chemical formula 1.

[0151] The analytical results of the compound represented by chemical formula 4 are as follows.

[0152] MALDI-TOF MS: 703.16 m / z [Preparation Example] [5] [Based on chemical formula] [5] [Synthesis of the represented compound] (Reaction Scheme 14)

[0153] Compound 5a was synthesized in the same manner as compound 2b, except that compound 1f was used instead of compound 2a. (Reaction Scheme 15)

[0154] Compound 5b was synthesized in the same manner as compound 2c, except that compound 5a was used instead of compound 2b. (Reaction Scheme 16) Chemical formula 5

[0155] Except for using compound 5b instead of compound 1g, the compound represented by chemical formula 5 was synthesized in the same manner as the material corresponding to chemical formula 1.

[0156] The analytical results for the compound represented by chemical formula 5 are as follows.

[0157] MALDI-TOF MS: 768.12 m / z [Comparative Preparation Example] [1] [Based on chemical formula] [C-1] [Synthesis of the represented compound] (Reaction Scheme 17)

[0158] Compound 1a (10.0 mmol) and potassium carbonate (K₂CO₃, 20.0 mmol) were added to 35.0 mL of tetrahydrofuran (THF), and the mixture was then cooled to 0 °C. Compound 6a (30.0 mmol) was added dropwise, and the mixture was stirred overnight at 80 °C. When the reaction was complete, distilled water was added to form a precipitate. The solid was separated by filtration under reduced pressure, washed with distilled water, and dried overnight in a vacuum oven to obtain compound 6b. (Reaction Scheme 18) Chemical formula C-1

[0159] Except for using compound 6b instead of compound 1g, the compound represented by chemical formula C-1 was synthesized in the same manner as the material corresponding to chemical formula 1.

[0160] The analytical results of the compound represented by chemical formula C-1 are as follows.

[0161] MALDI-TOF MS: 514.11 m / z [Comparative Preparation Example] [2] [Based on chemical formula] [C-2] [Synthesis of the represented compound] (Reaction Scheme 19)

[0162] Compound 7a was synthesized in the same manner as compound 6b, except that compound 2a was used instead of compound 6a. (Reaction Scheme 20) Chemical formula C-2

[0163] Except for using compound 7a instead of compound 1g, the compound represented by chemical formula C-2 was synthesized in the same manner as the material corresponding to chemical formula 1.

[0164] The analytical results of the compound represented by the chemical formula C-2 are as follows.

[0165] MALDI-TOF MS: 565.18 m / z [(Preparation of photosensitive resin composition)] [Example] [1] [To Example] [5] [And comparative examples] [1] [and comparative examples] [2]

[0166] Using the compositions shown in Table 1, the photopolymerization initiator was dissolved in a solvent and stirred at room temperature for 2 hours. Here, the polymer resin and photopolymerizable monomer were added, and the mixture was stirred at room temperature (25°C) for 1 hour, and then the entire solution was stirred again for 2 hours. The solution was filtered three times through a 0.45 μm filter to remove impurities, thereby producing each photosensitive resin composition. (Table 1) (Unit: weight%) Example 1 Example 2 Example 3 Example 4 Example 5 Comparative Example 1 Comparative Example 2 (A) Adhesive resin 17.5 17.5 17.5 17.5 17.5 17.5 17.5 (B) Photopolymerizable monomers (B-1) 7 - - - - - - (B-2) - 7 - - - - - (B-3) - - 7 - - - - (B-4) - - - 7 - - - (B-5) - - - - 7 - - (B-6) - - - - - 7 - (B-7) - - - - - - 7 (C) Photopolymerization initiator 1 1 1 1 1 1 1 (D) Solvent 74.5 74.5 74.5 74.5 74.5 74.5 74.5 (A) Adhesive resin Acrylic adhesive resin (SP-RY38; Resonac) (B) Photopolymerizable monomers (B-1) Preparation of photopolymerizable monomers in Example 1 (B-2) Preparation of photopolymerizable monomers in Example 2 (B-3) Preparation of photopolymerizable monomers in Example 3 (B-4) Preparation of photopolymerizable monomers in Example 4 (B-5) Preparation of photopolymerizable monomers in Example 5 (B-6) Comparative Preparation of Photopolymerizable Monomers in Example 1 (B-7) Comparative Preparation Example 2: Photopolymerizable Monomer (C) Photopolymerization initiator Oxime initiator (SPI-03, Samyang Corporation) (D) Solvent Propylene glycol monomethyl ether acetate (PGMEA, Daicel) [Evaluate]

[0167] After confirming that the photosensitive resin compositions according to Examples 1 to 5 and Comparative Examples 1 and 2 were all transparent, their refractive index at 550 nm was measured. Subsequently, each of these was coated onto an 8-inch silicon wafer using SEMES K-SPIN at revolutions per minute (rpm) capable of exhibiting similar thicknesses, followed by soft baking on a heated plate at 100°C, and pattern exposure was performed on an i-line stepper manufactured by Nikon Corp. under the following exposure conditions (dose: 200 ms / focal length: -0.3). During the exposure process, after thickness measurement using TENCOR, the coated substrate was developed to reveal the pattern. In this paper, EHD-100S solution (TMAH) was used as the developer, and the time (seconds) required for pattern appearance (BP) was measured.

[0168] The sensitivity and residue of the pattern on the developed substrate were examined using a critical dimension scanning electron microscope (CD-SEM) manufactured by Hitachi, Ltd. The pattern was confirmed to be a 96 μm negative pattern, and large areas of residue were confirmed using an Olympus optical microscope. The results are shown in Table 2. The evaluation criteria for developability and pattern linearity are shown in Table 3. (Table 2) Example 1 Example 2 Example 3 Example 4 Example 5 Comparative Example 1 Comparative Example 2 Refractive index 1.727 1.715 1.711 1.702 1.698 1.51 1.56 Developing time (seconds) 10 10 10 10 10 No development No development Developability ○ ○ ○ ○ ○ X X Pattern linearity ◎ ◎ ◎ ◎ ◎ X X (Table 3) Developability Pattern linearity ◎ No residue Very good linearity ○ Only a small amount of residue remained around the pattern. Excellent linearity △ Residues were present in all areas. Lack of linearity X No development Very poor linearity

[0169] Based on the above evaluation, it can be seen that the photosensitive resin composition according to some exemplary embodiments is a transparent photosensitive resin composition that not only has a very high refractive index at 550 nm, but also has excellent pattern linearity and residue characteristics even when cured at low temperature, making it suitable for use as a microlens surrounding a color filter in a micro-OLED.

[0170] Although the invention has been described in conjunction with embodiments now considered practical examples, it should be understood that the invention is not limited to the disclosed embodiments, but rather is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. Therefore, the foregoing embodiments should be understood as exemplary and not as limiting the invention in any way.

[0171] 100: Silicon wafers 200:OLED substrate 300: Inorganic layer 400: Adhesive protective layer 500: Microlens layer R: Red Filter G: Green Filter B: Blue Filter

Claims

1. A photosensitive resin composition comprising: an adhesive resin; a photopolymerizable monomer; a photopolymerization initiator; and a solvent, wherein the photopolymerizable monomer is represented by Formula 1: Formula 1 wherein in Formula 1, R1 to R3 are each independently a hydrogen atom or a substituted or unsubstituted C1 to C20 alkyl group, L1 to L4 are each independently a substituted or unsubstituted C6 to C20 aryl group, L5 is a single bond or a substituted or unsubstituted C6 to C20 aryl group, L6 is a substituted or unsubstituted C1 to C20 alkyl group or a substituted or unsubstituted C6 to C20 aryl group, and X is a single bond, *-S-* or *-NR'-*, wherein R' is a hydrogen atom or a C1 to C10 alkyl group, wherein, based on the total amount of the photosensitive resin composition, the photosensitive resin composition comprises: 10% to 30% by weight of the adhesive resin; 3% to 15% by weight of the photopolymerizable monomer; 0.1% to 5% by weight of the photopolymerization initiator; and the balance being the solvent.

2. The photosensitive resin composition as claimed in claim 1, wherein all L1 to L4 are identical.

3. The photosensitive resin composition as claimed in claim 1, wherein all of R1 to R3 are identical.

4. The photosensitive resin composition as claimed in claim 1, wherein L5 is a substituted or unsubstituted C6 to C20 aryl group, and X is a single bond or *-S-*.

5. The photosensitive resin composition as claimed in claim 1, wherein L5 is a single bond and X is *-S-* or *-NR'-*, wherein R' is a hydrogen atom or a C1 to C10 alkyl group.

6. The photosensitive resin composition as claimed in claim 1, wherein L5 is a single bond and X is a single bond.

7. The photosensitive resin composition as claimed in claim 1, wherein the photopolymerizable monomer is represented by any one of chemical formulas 1-1 to 1-5: Chemical Formula 1-1 Chemical Formula 1-2 Chemical Formula 1-3 Chemical Formula 1-4 Chemical Formula 1-5.

8. The photosensitive resin composition of claim 1, wherein the photosensitive resin composition further comprises malonic acid, 3-amino-1,2-propanediol, a silane coupling agent, a leveling agent, a surfactant, a polymerization inhibitor, or a combination thereof as an additive.

9. The photosensitive resin composition of claim 1, wherein the photosensitive resin composition has a refractive index greater than or equal to 1.66 at 550 nm.

10. The photosensitive resin composition of claim 1, wherein the photosensitive resin composition has a transmittance of greater than or equal to 90% at 400 nm to 700 nm.

11. A photosensitive resin layer, manufactured using the photosensitive resin composition as described in claim 1.

12. A display device comprising a photosensitive resin layer as described in claim 11.

13. The display device of claim 12, wherein the display device is a micro organic light-emitting diode (OLED) display device, the micro organic light-emitting diode display device comprising an organic light-emitting diode substrate located on a silicon wafer and a color filter layer, the color filter layer being located on the organic light-emitting diode substrate and converting white light generated from the organic light-emitting diode substrate into light of multiple colors, wherein the photosensitive resin layer of claim 11 is located on the organic light-emitting diode substrate and the color filter layer, and the color filter layer comprising a red color filter, a green color filter, and a blue color filter.

14. A method for manufacturing a photosensitive resin layer, comprising: Coating with the photosensitive resin composition as described in claim 1; After the coating is applied, pre-baking is performed at a temperature of 100°C or less. After the pre-baking process, the sample is exposed to i-line; and then developed.

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