Composition for protecting inkjet printing film, protective layer comprising same, device comprising same, and method for preparing same

Abstract

The present invention relates to a protective composition, a protective layer comprising same, an encapsulated device comprising same, and a method for preparing same. The protective composition of the present invention encapsulates a color conversion layer of an image display device, thereby maintaining light conversion efficiency, improving resistance to moisture and oxygen, and enhancing plasma resistance and thermal stability.

Description

Composition for protecting inkjet printing films, protective layer comprising the same, device comprising the same, and method for manufacturing the same

[0001] The present invention relates to a composition for protecting an inkjet printing film, a protective layer including the same, an apparatus including the same, and a method for manufacturing the same.

[0002] Quantum dots are nanometer-sized semiconductor nanocrystals characterized by an energy band gap (Eg) that varies depending on their size and shape. Due to the quantum confinement effect, the emission wavelength of these quantum dots can be controlled solely by adjusting their size, and they can exhibit excellent color purity and high photoluminescence (PL) efficiency. As a result, they are receiving significant attention not only in displays but also in fields such as lighting sources, solar cells, semiconductor lasers / optical amplifiers, and bioimaging.

[0003] Meanwhile, the formation of micropixels is essential for applying quantum dot color converter (QDCC) materials to ultra-high-resolution, high-color reproduction displays, and accordingly, various micro-patterning technologies for quantum dot color converter materials are being researched.

[0004] Micropixel formation technologies for quantum dot color conversion materials are broadly categorized into photolithography and ink-jet printing processes. While photolithography is advantageous for forming fine patterns of smaller sizes, it includes numerous processes such as exposure and development that can reduce the quantum efficiency of quantum dots, resulting in a significant decrease in efficiency compared to the initial efficiency and high material consumption. In contrast, ink-jet printing is gaining attention because it eliminates exposure and development processes when using solvent-type ink, and eliminates development and post-baking processes when using solvent-free ink, thereby minimizing the drop in efficiency compared to the initial efficiency and having the advantage of low material consumption.

[0005] Quantum dot color-converting materials have a problem in that the photo-converting efficiency of the quantum dots themselves decreases when exposed to air; therefore, a separate protective layer can be manufactured to seal and protect the color-converting layer containing the quantum dots. The manufacturing process for such a protective layer generally involves injecting quantum dot ink, followed by a curing process and a pre-oxidation bake (POB) process, and then producing it through a chemical vapor deposition (CVD) process or other encapsulation process.

[0006] Current technology involves fabricating a quantum dot ink film and then undergoing an inorganic encapsulation process, such as SiON, through Plasma-Enhanced Chemical Vapor Deposition (PECVD). This process, in which a quantum dot (QD) plasma inorganic thin film layer is formed to achieve the encapsulation and planarization effects of conventional inkjet, has disadvantages such as a complex manufacturing method, the need for vacuum conditions, the use of toxic gases, and damage to the underlying layer (QD layer) caused by heat and plasma.

[0007] In addition, the PECVD process is expensive, and there is a possibility of air exposure during the process and oxidation due to air exposure, so improvements are needed.

[0008] The present invention aims to solve the aforementioned problem and other related problems.

[0009] One exemplary objective of the present invention is to provide a protective composition that maintains the photoconversion efficiency of quantum dots and improves resistance to moisture and oxygen.

[0010] Another exemplary object of the present invention is to provide a protective layer comprising the protective composition and an apparatus comprising the same.

[0011] Another exemplary objective of the present invention is to provide the protective composition, the protective layer, and a method for manufacturing a device comprising the same.

[0012] The technical problems to be solved according to the technical concept of the invention disclosed in this specification are not limited to those for solving the problems mentioned above, and other unmentioned problems will be clearly understood by a person skilled in the art from the description below.

[0013] To achieve the above objective, one example of the present invention provides a composition for protecting an inkjet printing film comprising at least one curable monomer; and at least one antioxidant among compounds represented by the following chemical formulas 1 to 4.

[0014] [Chemical Formula 1]

[0015]

[0016] [Chemical Formula 2]

[0017]

[0018] [Chemical Formula 3]

[0019]

[0020] [Chemical Formula 4]

[0021]

[0022] In the above chemical formulas 1 to 4,

[0023] The above R' are identical or different from each other, and each independently C, O, S, N, substituted or unsubstituted C1-C 40 alkylene groups, substituted or unsubstituted C1-C 40 cycloalkylene groups of, substituted or unsubstituted C1-C 40 alkyloxylene groups, substituted or unsubstituted C6-C 40 Selected from the group consisting of an arylene group or a substituted or unsubstituted heteroarylene group having 5 to 40 nuclei,

[0024] The above R1 to R4 are identical or different from each other, and each independently hydrogen, hydroxyl group, acrylic group, halogen, cyano group, nitro group, C1-C 40 alkyl group of, C2-C 40 alkenyl group of, C2-C 40 alkynyl groups, substituted or unsubstituted C3-C 40 The cycloalkyl group of, and substituted or unsubstituted C6-C 60 It is selected from a group consisting of aryls,

[0025] n is an integer from 1 to 4.

[0026] Another example of the present invention provides a protective layer comprising the above protective composition.

[0027] Another example of the present invention provides an image display device comprising a substrate; a lower layer; and an upper layer, wherein the substrate includes a light source, the lower layer includes a color conversion layer, and the upper layer includes a protective layer.

[0028] Another example of the present invention provides a method for manufacturing an image display device comprising the steps of: providing a substrate; forming a lower layer on the substrate; and forming an upper layer on the lower layer, wherein the step of forming the lower layer includes an inkjet printing process and a curing process, and the step of forming the upper layer includes a process of treating the protective composition on the lower layer and a curing process.

[0029] By forming a protective layer with the protective composition of the present invention, photoconversion efficiency can be maintained, moisture and oxygen resistance can be improved, and plasma resistance and high-temperature stability can be improved.

[0030] In addition, the protective layer formed from the above protective composition can be used as a flexible protective layer and can be used in a flexible image display device.

[0031] Meanwhile, the scope of the present invention is not limited by the effects described above.

[0032] Figure 1 is the result of measuring and confirming the power conversion efficiency of an image display device including a protective layer prepared with a protective composition according to an example of the present invention, according to the thickness of the protective layer.

[0033] Figure 2 is the result of measuring and confirming the power conversion efficiency of an image display device including a protective layer manufactured with a protective composition according to an example of the present invention at each manufacturing step.

[0034] Figure 3 is the result of measuring and confirming the blue backlight light conversion brightness of an image display device including a protective layer prepared with a protective composition according to an example of the present invention.

[0035] Figure 4 is a result showing an enlarged view of the wavelength range from 500 nm to 575 nm in the result of Figure 3 above.

[0036] The present invention will be described in detail as follows.

[0037] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. The embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art, and the following embodiments may be modified in various different forms, and the scope of the present invention is not limited to the following embodiments.

[0038] Unless otherwise defined, all terms used in this specification (including technical and scientific terms) may be used in a meaning commonly understood by those skilled in the art to which the present invention pertains. Additionally, terms defined in commonly used dictionaries are not to be interpreted ideally or excessively unless explicitly and specifically defined otherwise.

[0039] Furthermore, the size and thickness of each component shown in the drawings are depicted arbitrarily for convenience of explanation, and thus the present invention is not necessarily limited to what is illustrated. Thicknesses have been enlarged in the drawings to clearly represent various layers and regions. Additionally, for convenience of explanation, the thickness of some layers and regions has been exaggerated in the drawings.

[0040] Furthermore, throughout the specification, when a part is described as "comprising" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components. Also, throughout the specification, the terms "above" or "on" mean not only cases where a part is located above or below the subject part but also cases where another part is located in between, and do not necessarily mean that it is located above based on the direction of gravity. Furthermore, in this specification, terms such as "first," "second," etc., are used to distinguish components from one another, rather than indicating an arbitrary order or importance.

[0041] In addition, throughout the specification, "planar" means when the subject part is viewed from above, and "cross-sectional" means when the cross-section obtained by vertically cutting the subject part is viewed from the side.

[0042] In this specification, "(meth)acrylate" refers to acrylate and methacrylate, "(meth)acryl" refers to acryl and methacryl, and "(meth)acryloyl" refers to acryloyl and methacryloyl.

[0043] In addition, in this specification, "monomer" and "monomer" have the same meaning. A monomer in the present invention is distinguished from an oligomer, polymer, or resin, which is a polymer polymerized from the monomer, and refers to a compound having a weight-average molecular weight of 1,000 g / mol or less. In this specification, "polymerizable functional group" refers to a group involved in a polymerization reaction, such as a (meth)acrylate group.

[0044] In this specification, 'substituted or unsubstituted' may mean that one or more hydrogen atoms of the functional groups of the present invention are substituted with a halogen (F, Cl, Br or I), a hydroxyl group, a nitro group, a cyano group, an imino group (=NH, =NR, where R is an alkyl group having 1 to 10 carbon atoms), an amino group (-NH2, -NH(R'), -N(R")(R"'), R', R", R"' are each independently an alkyl group having 1 to 10 carbon atoms), an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a heteroaryl group having 5 to 20 nuclei, a heterocycloalkyl group having 2 to 30 nuclei, and an arylalkyl group having 7 to 21 carbon atoms.

[0045] In this specification, solid content refers to components other than solvents in a protective composition. Therefore, even if a component is in a liquid state, it is considered solid content if it is not used as a solvent. Additionally, in this specification, '*' may indicate an inter-elemental bonding site.

[0046] In the present invention, the term "quantum dot" refers to a nanocrystal exhibiting quantum confinement or exciton confinement and is a type of luminescent nanostructure (e.g., capable of emitting light upon energy excitation). The shape of the term quantum dot is not limited unless specifically defined otherwise.

[0047] The above nanostructure refers to a structure having a single region or characteristic dimensions having nanoscale dimensions. The above nanostructure may have any shape, such as a nanowire, nanorod, nanotube, multi-pod type shape having two or more pods, nanodot (or quantum dot), etc., and is not particularly limited.

[0048] The electrical and / or optical properties of the quantum dots of the present invention may vary depending on their properties (e.g., composition, size, and / or shape). For example, quantum dots may have a large surface area per unit volume, exhibit quantum confinement effects, and exhibit properties different from those of bulk materials of the same composition.

[0049] In the present invention, the type of quantum dot is not particularly limited and includes all known or commercially available quantum dots.

[0050] In one embodiment of the present invention, the quantum dots are InP, CdSe, AgInGaS, ZnSeTe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, MgS, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe, MgZnS, ZnSeSTe, HgZnTeS, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, It can be selected from the group consisting of HgZnSTe and mixtures thereof.

[0051]

[0052] [Protective composition]

[0053] The protective composition according to the present invention is a protective composition for sealing a part of an image display device, comprising a curable monomer and an antioxidant.

[0054] In one specific example, the composition comprises at least one curable monomer; and an antioxidant, wherein the at least one curable monomer may be a photocurable monomer or a thermocurable monomer, and comprises a curable monomer represented by the following chemical formulas 7 to 11 or an oligomer thereof. If necessary, at least one additional conventional photocurable monomer, thermocurable monomer, antioxidant, and additive known in the art may be included.

[0055] The protective composition according to the present invention may be a solvent-free type that does not contain a solvent. Unlike the solvent type, the solvent-free type can improve the problems of reduced jettability and poor coating properties caused by the inclusion of a solvent.

[0056] The protective composition according to the present invention can be used to form a protective layer of an inkjet-printed film.

[0057]

[0058] The composition of the above protective composition is described in detail below.

[0059]

[0060] antioxidants

[0061] The protective composition according to the present invention may include an antioxidant (heat stabilizer).

[0062] These antioxidants serve to improve the thermal stability of the protective layer after curing, and conventional antioxidants known in the field may be used without limitation.

[0063] In the present invention, at least one of the antioxidants represented by the following chemical formulas 1 to 4 may be used.

[0064] [Chemical Formula 1]

[0065]

[0066] [Chemical Formula 2]

[0067]

[0068] [Chemical Formula 3]

[0069]

[0070] [Chemical Formula 4]

[0071]

[0072] In the above chemical formulas 1 to 4,

[0073] The above R' are identical or different from each other, and each independently C, O, S, N, substituted or unsubstituted C1-C 40 alkylene groups, substituted or unsubstituted C1-C 40 cycloalkylene groups of, substituted or unsubstituted C1-C 40alkyloxylene groups, substituted or unsubstituted C6-C 40 Selected from the group consisting of an arylene group or a substituted or unsubstituted heteroarylene group having 5 to 40 nuclei,

[0074] The above R1 to R4 are identical or different from one another, and each independently hydrogen, hydroxyl group, acrylic group, halogen, cyano group, nitro group, C1-C 40 alkyl group of, C2-C 40 alkenyl group of, C2-C 40 alkynyl groups, substituted or unsubstituted C3-C 40 The cycloalkyl group of, and substituted or unsubstituted C6-C 60 It is selected from a group consisting of aryls,

[0075] n is an integer from 1 to 4.

[0076] In the present invention, the antioxidant may include at least one of the compounds represented by the following chemical formulas 5 and 6.

[0077] [Chemical Formula 5]

[0078]

[0079] [Chemical Formula 6]

[0080]

[0081] In the present invention, the content of the antioxidant is not particularly limited and can be appropriately adjusted within a range known in the art. For example, the antioxidant may be included in an amount of 0.1 parts by weight or more, 0.5 parts by weight or more, 1 part by weight or more, 3 parts by weight or more, 5 parts by weight or more, or 7 parts by weight or more per 100 parts by weight of the protective composition according to the present invention, and may be included in an amount of 20 parts by weight or less, 15 parts by weight or less, 10 parts by weight or less, 7 parts by weight or less, 5 parts by weight or less, or 3 parts by weight or less per 100 parts by weight, preferably 0.01 to 3 parts by weight relative to 100 parts by weight, and specifically 0.01 to 1 part by weight. When the content of the antioxidant falls within the aforementioned range, it prevents the deterioration of the protective layer after curing and can exhibit excellent thermal stability.

[0082] In quantum dot displays, quantum dots are formed in a structure where organic ligands are weakly bound to a surface composed of inorganic materials; consequently, the surface is not protected by strong bonds such as covalent bonds, which leads to reduced efficiency when applied to thin film formation and photoconversion devices. Specifically, the quantum dots are produced by forming a thin film via inkjet, followed by a curing process and a pre-oxidation bake (POB) process, and then undergoing a chemical vapor deposition (CVD) process or other encapsulation processes. At this stage, exposure to air can lead to a decrease in the photoconversion efficiency (PCE) and photoconversion stability of the quantum dots. Furthermore, the stability of the quantum dots can be significantly reduced due to degradation caused by oxygen, moisture, and free radicals; therefore, it is necessary to improve stability against exposure to heat, air, and light. Accordingly, the protective composition may include an antioxidant.

[0083]

[0084] Curable monomer

[0085] The protective composition according to the present invention comprises one or more conventional photocurable monomers known in the art as compounds that polymerize by light of a specific wavelength, such as ultraviolet (UV) light, or conventional thermosetting monomers known in the art as compounds that polymerize by heat of a specific temperature, such as 40°C, 50°C, 60°C, 70°C, 80°C, 100°C or higher.

[0086] As a specific example, the curable monomer may include at least one of the monomers represented by the following chemical formulas 7 to 11 or the oligomers thereof.

[0087] [Chemical Formula 7]

[0088]

[0089] [Chemical Formula 8]

[0090]

[0091] [Chemical Formula 9]

[0092]

[0093] [Chemical Formula 10]

[0094]

[0095] [Chemical Formula 11]

[0096]

[0097] In the above chemical formulas 7 to 11,

[0098] The above R5, R7 and R 10 is a (meth)acrylate group, and

[0099] The above R6, R8, R9, R 17 and R 18 They are identical or different from each other, and each independently hydrogen, hydroxyl group, acryl group, halogen, cyano group, nitro group, C1-C 40 alkyl group of, C2-C 40 alkenyl group of, C2-C 40 alkynyl groups, substituted or unsubstituted C3-C40 cycloalkyl group of, C6-C 60 Selected from the group consisting of an aryl group and a substituted or unsubstituted heteroaryl group having 5 to 40 nuclei,

[0100] The above R 11 to R 16 They are identical or different from one another, and each independently hydrogen, hydroxyl group, acrylic group, (meth)acrylate group, halogen, cyano group, nitro group, C1-C 40 alkyl group of, C2-C 40 alkenyl group of, C2-C 40 alkynyl groups, substituted or unsubstituted C3-C 40 The cycloalkyl group of, and substituted or unsubstituted C6-C 60 Selected from the group consisting of the aryl group of, wherein R 11 to R 16 One or more of them are (meth)acrylate groups, and

[0101] m1 to m3 are identical or different from each other and are integers from 1 to 12, and

[0102] m4 is an integer from 1 to 14, and

[0103] The above Z is C, O, S, N, substituted or unsubstituted C1-C 40 alkylene groups, substituted or unsubstituted C1-C 40 cycloalkylene groups of, substituted or unsubstituted C1-C 40 alkyloxylene groups, substituted or unsubstituted C6-C 40 It is selected from the group consisting of an arylene group or a substituted or unsubstituted heteroarylene group having 5 to 40 nuclei.

[0104] As another specific example, the curable monomer may include at least one of the compounds represented by the following chemical formulas 12 to 14.

[0105] [Chemical Formula 12]

[0106]

[0107] [Chemical Formula 13]

[0108]

[0109] [Chemical Formula 14]

[0110]

[0111] As an example of the present invention, a compound represented by any one of the formulas 7 to 14 may include one or more (meth)acrylate groups.

[0112] As an example of the present invention, a compound represented by any one of the formulas 7 to 14 may include a trifunctional (meth)acrylic group or a tetrafunctional (meth)acrylic group.

[0113] In the present invention, a compound represented by any one of the formulas 7 to 14 may be included in an amount of 5 parts by weight or more, 10 parts by weight or more, 15 parts by weight or more, 20 parts by weight or more, 25 parts by weight or more, or 30 parts by weight or more, based on a total of 100 parts by weight of the protective composition.

[0114] In the present invention, a compound represented by any one of the formulas 7 to 14 may be included in an amount of 50 parts by weight or less, 40 parts by weight or less, 35 parts by weight or less, or 30 parts by weight or less, based on a total of 100 parts by weight of the protective composition.

[0115]

[0116] additives

[0117] In addition to the aforementioned components, the adhesive composition of the present invention may use at least one additive known in the art without limitation, within a range that does not impede the effect of the invention.

[0118] Examples of usable additives include light stabilizers, heat stabilizers, photoinitiation promoters, heat initiation promoters, leveling agents, toughening agents, thickeners, solvents, etc. These may be used alone or in combination of two or more. In this case, the content of the additives can be appropriately adjusted within a range known in the art and is not particularly limited. For example, at least one of the above additives may be included in an amount of 0.01 to 5 parts by weight, specifically 0.01 to 2 parts by weight, based on the total weight of the adhesive composition.

[0119]

[0120] The type of photopolymerization initiator is not particularly limited and may include, for example, triazine compounds, acetophenone compounds, benzophenone compounds, thioxanthone compounds, benzoin compounds, oxime ester compounds, aminoketone compounds, phosphine or phosphine oxide compounds, carbazole compounds, diketone compounds, sulfonium borate compounds, diazo compounds, nonimidazole compounds, or combinations thereof.

[0121] Examples of the above 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, 2-(p-tolyl)-4,6-bis(trichloromethyl)-s-triazine, 2-biphenyl-4,6-bis(trichloromethyl)-s-triazine, and bis(trichloromethyl)-6-styryl-s-triazine. Examples include 2-(naphtho-1-yl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4-methoxynaphtho-1-yl)-4,6-bis(trichloromethyl)-s-triazine, 2-4-bis(trichloromethyl)-6-piperonyl-s-triazine, 2-4-bis(trichloromethyl)-6-(4-methoxystyryl)-s-triazine, etc.

[0122] Examples of the above acetophenone-based compounds include 2,2'-diethoxyacetophenone, 2,2'-dibutoxyacetophenone, 2-hydroxy-2-methylpropiophenone, pt-butyltrichloroacetophenone, pt-butyldichloroacetophenone, 4-chloroacetophenone, 2,2'-dichloro-4-phenoxyacetophenone, 2-methyl-1-(4-(methylthio)phenyl)-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, etc.

[0123] Examples of the above benzophenone compounds include benzophenone, benzoyl benzoic acid, methyl benzoyl benzoate, 4-phenyl benzophenone, hydroxybenzophenone, acrylated benzophenone, 4,4'-bis(dimethylamino)benzophenone, 4,4'-bis(diethylamino)benzophenone, 4,4'-dimethylaminobenzophenone, 4,4'-dichlorobenzophenone, 3,3'-dimethyl-2-methoxybenzophenone, etc.

[0124] Examples of the above thioxanthonic compounds include thioxanthon, 2-methylthioxanthon, isopropylthioxanthon, 2,4-diethylthioxanthon, 2,4-diisopropylthioxanthon, 2-chlorothioxanthon, etc.

[0125] Examples of the above-mentioned benzoin compounds include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzyl dimethyl ketal, etc.

[0126] In the above composition, the content of the photopolymerization initiator can be appropriately adjusted by taking into account the type and content of the photopolymerizable monomer used.

[0127] In one embodiment, the content of the photopolymerization initiator may be 0.01 wt% or more, 0.1 wt% or more, 0.5 wt% or more, or 1 wt% or more based on 100 wt% of the total composition. The content of the photopolymerization initiator may be 10 wt% or less, or 5 wt% or less based on the total weight of the composition, but is not limited thereto.

[0128] It is desirable that the photopolymerization initiator be included within the above range, as this improves pattern formation and increases the sensitivity of the light conversion protection composition, thereby tending to improve the strength of the pixel portion formed using the composition or the smoothness of the surface of the pixel portion.

[0129] The types of light scattering agents mentioned above are not particularly limited and may include, for example, barium sulfate (BaSO4), calcium carbonate (CaCO3), titanium dioxide (TiO2), zirconia (ZrO2), or a combination thereof.

[0130] The light scattering agent reflects light that is not absorbed by the quantum dots and enables the quantum dots to reabsorb the reflected light. In other words, the light scattering agent increases the amount of light absorbed by the quantum dots, thereby increasing the light conversion efficiency of the protective composition.

[0131] The form of use of the above light scattering agent is not particularly limited, and as an example, a dispersion in a solvent can be used for dispersion stability on the protective composition.

[0132] In the above composition, the light scattering agent content can be appropriately adjusted as needed.

[0133] In one embodiment, the content of the light scattering agent may be 0.1 weight% or more, 0.5 weight% or more, 1 weight% or more, or 5 weight% or more based on 100 weight% of the total composition. The content of the light scattering agent may be 10 weight% or less, or 5 weight% or less based on the total weight of the composition, but is not limited thereto.

[0134] When the above light scattering agent is included within the above content range, an improvement in light conversion efficiency due to the use of the light scattering agent can be expected, and pattern characteristics can also be improved.

[0135]

[0136] The protective composition has a low viscosity, having a viscosity greater than 0 and less than or equal to 100 cps, and preferably 10 to 50 cps. When having the viscosity described above, outgassing is easy, and a flexible protective layer can be formed, which is suitable for inkjet processes.

[0137] The above protective composition not only contains at least one compound having a curable functional group within the molecule, but also exhibits the low viscosity characteristic, thereby forming a flexible protective layer compared to organic, inorganic, organic-inorganic composite layers and glass hard encapsulations, and can be used in flexible devices.

[0138]

[0139] High-refractive index monomer

[0140] The above protective composition may further include a high-refractive-index monomer represented by the following chemical formula 15.

[0141] [Chemical Formula 15]

[0142]

[0143] In the above chemical formula 15,

[0144] The above X are identical or different from one another, and each independently hydrogen, hydroxyl group, acrylic group, cyano group, nitro group, C1-C 40 alkyl group of, C2-C 40 alkenyl group of, C2-C 40 alkynyl groups, substituted or unsubstituted C6-C 40 Selected from the group consisting of an aryl group and a substituted or unsubstituted heteroaryl group having 5 to 40 nuclear atoms,

[0145] The above Y is hydrogen, hydroxyl group, acrylic group, cyano group, nitro group, C1-C 40 alkyl group of, C2-C 40 alkenyl group of, C2-C 40 alkynyl groups, substituted or unsubstituted C6-C 40Selected from the group consisting of an aryl group and a substituted or unsubstituted heteroaryl group having 5 to 40 nuclear atoms,

[0146] m5 is an integer from 0 to 12, and

[0147] The above A are identical or different from each other and are C, O, S or N.

[0148] Here, the above Y is

[0149]

[0150] It can be one or more of them.

[0151] In this case, * represents the site that binds to Y in chemical formula 15.

[0152] The above high-refractive index monomer includes an aromatic ring structure such as an aryl group or arylene, preferably a phenyl group, phenylene, biphenyl group, or terphenyl group. High-refractive index monomers with such a structure exhibit an electron-dense compound structure through π-ð interaction, which can improve the refractive index of a protective layer formed from a protective composition containing the above high-refractive index monomer.

[0153] A protective layer prepared from a protective composition containing the above high-refractive index monomer has low viscosity characteristics of 10 to 50 cps and simultaneously has a refractive index of 1.4 or higher, 1.45 or higher, 1.5 or higher, preferably 1.48 or higher. In addition, a flexible protective layer is formed, so it can be used in a flexible image display device.

[0154] A protective layer prepared with a protective composition containing the above-mentioned high-refractive index monomer has high photoconversion efficiency, high plasma resistance, and improved stability against high temperatures.

[0155]

[0156] [Protection Layer]

[0157] Another example of the present invention provides a protective layer comprising a cured product of the protective composition.

[0158] The characteristics of the above protective layer are described in detail below.

[0159] The above protective layer may have a thickness of 0.1 to 10 μm.

[0160] The protective layer may have a refractive index of 1.4 to 1.47. However, if the protective layer comprises a cured product of a protective composition containing the high-refractive index monomer, it may have a high refractive index of 1.48 or higher.

[0161] The protective layer according to the present invention can be directly adhered to a film such as a light-emitting layer or a color-converting layer, and at the same time exhibit a light extraction effect through its high refractive index characteristics, thereby reducing light loss.

[0162] The protective layer according to the present invention can be flattened. The protective layer cured by the protective composition can form a flatness of a certain level or higher, thereby forming a low level of surface roughness and exhibiting a light extraction effect. This corresponds to an effect similar to or improved upon the characteristics of a protective layer formed by conventional CVD.

[0163]

[0164] [Image display device]

[0165] Another example of the present invention provides an image display device comprising a substrate; a lower layer; and an upper layer, wherein the substrate comprises a light source, the lower layer comprises a color conversion layer, and the upper layer comprises a protective layer comprising a cured product of the protective composition.

[0166] The light source may be a blue light source, a white light source, an LCD light source, and may include an organic light-emitting diode light source. Here, the blue light backlight unit may be a blue organic light-emitting diode.

[0167] The above image display device may be a flexible image display device. The protective layer according to the present invention can be applied to a flexible image display device due to the characteristic of forming a soft protective layer.

[0168] The substrate may include a bank structure that isolates quantum dots, an organic light-emitting diode layer, or a combination thereof. The bank may be located across all or part of the lower layer or all or part of the upper layer and may perform different roles depending on the type of image display device. As an example of an image display device according to the present invention, when the image display device is a quantum dot organic light-emitting diode, the bank may be used to isolate quantum dots that cause different color conversions in the color conversion layer.

[0169]

[0170] [Manufacturing Method]

[0171] Another example of the present invention is a method for manufacturing an image display device comprising the steps of: providing a substrate; forming a lower layer on the substrate; and forming an upper layer on the lower layer, wherein the step of forming the lower layer may include at least one process selected from the group consisting of an inkjet printing process, a curing process, and a thermal stabilization (POB) process, preferably may include an inkjet printing process and a curing process, and optionally may include a thermal stabilization process. The step of forming the upper layer provides a manufacturing method comprising a process of treating the protective composition on the lower layer and a curing process.

[0172] In one example according to the present invention, the image display device may be a device including quantum dots and an organic light-emitting diode, and the inkjet printing process may be a process for printing quantum dot ink.

[0173] The method of manufacturing an image display device according to the present invention may be performed in conjunction with the method of forming a protective layer comprising an inorganic layer including an inorganic material such as SiON, an organic layer, and / or an organic-inorganic composite layer through a chemical vapor deposition process, or in addition to the method of forming a protective layer through a chemical vapor deposition process, and the method of manufacturing an image display device according to the present invention may form a protective layer by curing the protective composition.

[0174] After inkjet printing, a chemical vapor deposition process is carried out through curing and thermal stabilization processes, during which time exposure to air may occur during the process.

[0175]

[0176] The method for manufacturing an image display device according to the present invention enables the step of forming an upper layer that continuously forms a protective layer in an environment identical or similar to the curing process of the lower layer after inkjet printing, for example under nitrogen conditions, thereby shortening the process time, simplifying the process, and reducing the cost of performing the process.

[0177] In addition, when the lower layer containing quantum dots is exposed to air, the photo-conversion efficiency may decrease and the brightness and safety may decrease; however, the method for manufacturing an image display device according to the present invention has the effect of increasing moisture resistance by 5 to 20 times or more and improving photo-conversion efficiency, brightness and safety by forming the protective layer.

[0178] In addition, the method for manufacturing an image display device according to the present invention has an environmentally friendly feature in that it does not use high-risk gases for performing the chemical vapor deposition process, as there is no chemical vapor deposition process for forming a protective layer.

[0179] The step of forming the upper layer may include a chemical vapor deposition process. At this time, the chemical vapor deposition process may be one or more processes selected from the group consisting of an atmospheric pressure chemical vapor deposition (APCVD) process, a low pressure chemical vapor deposition (LPCVD) process, a plasma enhanced chemical vapor deposition (PECVD) process, a high-density plasma chemical vapor deposition (HDPCVD) process, and an atomic layer chemical vapor deposition (ALCVD) process, and preferably, it may be a PECVD process. In addition, the chemical vapor deposition process may be carried out at 100 to 300°C, 100 to 280°C, 100 to 260°C, 100 to 250°C, 100 to 240°C, 100 to 220°C, 100 to 200°C, 120 to 300°C, 120 to 280°C, 120 to 260°C, 120 to 250°C, 120 to 240°C, 120 to 220°C, 120 to 200°C, 150 to 300°C, 150 to 280°C, 150 to 260°C, 150 to 250°C, 150 to 240°C, 150 to 220°C, preferably 100 to 200°C.

[0180] The chemical vapor deposition process described above may include a thermal stabilization process before and / or after the process. The above thermal stabilization process may be carried out at 100 to 300°C, 100 to 280°C, 100 to 260°C, 100 to 250°C, 100 to 240°C, 100 to 220°C, 100 to 200°C, 120 to 300°C, 120 to 280°C, 120 to 260°C, 120 to 250°C, 120 to 240°C, 120 to 220°C, 120 to 200°C, 150 to 300°C, 150 to 280°C, 150 to 260°C, 150 to 250°C, 150 to 240°C, 150 to 220°C, preferably 100 to 200°C.

[0181] As described above, the method for manufacturing an image display device according to the present invention does not require a chemical vapor deposition process to form a protective layer, but a protective layer may be additionally formed by performing a chemical vapor deposition process before or after manufacturing the protective layer according to the present invention.

[0182] The above curing process may be a photocuring or thermal curing process. If the above curing process is a photocuring process, it may be a process of irradiating ultraviolet (UV) rays, and if the above curing process is a thermal curing process, it may be a process of exposing the protective composition to heat, for example, 40°C, 50°C, 60°C, 70°C, 80°C, 100°C or higher.

[0183]

[0184] The present invention will be explained in more detail below through the following examples. However, these examples are intended to illustrate the invention and the scope of the invention is not limited to these examples.

[0185]

[0186] [Example 1]

[0187] A single film was fabricated by spin-coating the prepared quantum dot ink onto a glass substrate. The single film thickness was fabricated to be between 5 and 20 μm, and the fabricated single film underwent a thermal stabilization (POB) process after photocuring. Photocuring was performed at 8 J, and the thermal stabilization conditions were carried out at 100 to 200°C. Subsequently, a protective composition was spin-coated onto the upper layer of the single film to deposit a protective layer of 1 μm. The composition of the protective composition was prepared by combining materials of Chemical Formulas 7 to 11; specifically, it was prepared in the ratio of TCDDA 15 wt% (sigma-aldrich), HDDMA 75 wt% (Miwon), and IBOMA 10 wt% (sigma-aldrich).

[0188]

[0189] TCDDA: Tricyclodecane dimethanol diacrylate (CAS: 42594-17-2)

[0190] HDDMA: 1,6-Hexanediol dimethacrylate (CAS:6606-59-3)

[0191] IBOMA: Isobornyl Acrylate (CAS: 5888-33-5)

[0192]

[0193] In addition, the protective composition comprises one or more antioxidants among the compounds of Formulas 1 to 4. Specifically, the compound of Formula 5 (SONG 1035, Songwon Industrial Co., Ltd.) and the compound of Formula 6 (SONG 1135, Songwon Industrial Co., Ltd.) were mixed in a 1:1 ratio and used, and the antioxidant was added in an amount of 0.5 to 1 weight% relative to the weight of the ink. After coating the protective layer, it was exposed under 65% humidity conditions. At each step, the photo-conversion efficiency was analyzed by measuring the PCE (photo-conversion efficiency) using a quantum efficiency meter (QE-2100).

[0194] [Chemical Formula 5]

[0195]

[0196] [Chemical Formula 6]

[0197]

[0198] [Example 2]

[0199] It was manufactured by performing the same procedure as in Example 1, except that the protective layer was coated to 3 μm.

[0200]

[0201] [Example 3]

[0202] It is identical to Example 1 except that the protective layer is coated with 5 μm.

[0203]

[0204] [Comparative Example 1]

[0205] Instead of using a composition for a flexible protective layer in the protective layer as in Example 1, a Chemical Vapor Deposition (CVD) process was performed. The plasma thickness was 1-2 μm, and SiO x N y The tabernacle was established.

[0206]

[0207] [Experimental Example 1]

[0208] A protective layer was prepared using the protective composition prepared according to Examples 1 to 3 and Comparative Example 1, and the film thickness, transmittance, and color conversion efficiency (PCE) were measured in the following manner, and the results are shown in Table 1 below.

[0209] A thin film was fabricated by spin-coating a curable composition using a spin coater (SPIN3000D, MIDAS SYSTEM), and the thin film was cured using an exposure machine (SLC-1000AF-D, Jueun UV Tech). Subsequently, a thermal stabilization process was performed using a Corning heat stirrer (sigma-aldrich).

[0210] Film thickness was measured using a step height measuring instrument (DektakXT, BRUKER), and transmittance and color conversion efficiency (PCE) were measured using a quantum efficiency measuring instrument (QE-2100, Otsuka Electronics).

[0211]

[0212] [Table 1]

[0213]

[0214] As shown in Table 1, it was confirmed that the protective layer prepared by the method of preparing the protective layer of Examples 1 to 3 showed significantly improved resistance to moisture and oxygen compared to the protective layer (inorganic thin film layer) prepared by the PECVD process (Fig. 1). In particular, Comparative Example 1 showed a degradation rate of -13.2% when exposed for 7 days under 65% humidity, whereas the protective layer of Example 3 showed a degradation rate of -2.68%.

[0215] In addition, it was confirmed that while the photo-conversion efficiency decreased slightly in Comparative Example 1, the decrease in photo-conversion efficiency was relatively small or maintained in Examples 1 to 3, and it was confirmed that in Examples 1 to 3, the resistance to moisture and oxygen improved as the thickness of the protective layer increased.

[0216]

[0217] [Example 4]

[0218] Single films were fabricated by spin-coating the prepared quantum dot ink onto a glass substrate. Single film thicknesses were fabricated to be between 5 and 20 µm, and the fabricated single films underwent a photocuring followed by a post-treatment biomass (POB) process. Photocuring was performed at 8 J, and the POB conditions were maintained at 100 to 200 °C. Subsequently, a protective composition was spin-coated onto the top layer of the single film to deposit a 2 µm layer. The protective composition was prepared by blending compounds of Chemical Formulas 7 to 11, and 0.5 to 1 wt% of one or more antioxidants selected from Chemical Formulas 1 to 4 were added relative to the ink weight. Chemical Vapor Deposition (CVD) was then performed. The plasma thickness was 1–2 µm, and SiO₂ x N y The membrane was sealed, and a secondary thermal stabilization (POB) process was additionally performed. At each stage, the photovoltaic conversion efficiency was analyzed by measuring the PCE (photovoltaic conversion efficiency) using a QE-2100 instrument.

[0219]

[0220] [Comparative Example 2]

[0221] In Example 4, all processes were performed identically, except for the protective layer composition coating process.

[0222]

[0223] [Experimental Example 2]

[0224] A protective layer was prepared using the protective composition prepared according to Example 4 and Comparative Example 2, and the film thickness, transmittance, and color conversion efficiency (PCE) were measured in the following manner, and the results are shown in Table 2 below.

[0225] Thin films were fabricated by spin-coating a curable composition using a spin coater (SPIN3000D, MIDAS SYSTEM) and cured using a photolithography machine (SLC-1000AF-D, Jueun UV Tech). The Chemical Vapor Deposition (CVD) process was outsourced to an external agency, with a plasma thickness of 1–2 µm and SiO₂ x N y The membrane was formed. Afterwards, the thermal stabilization process was carried out using a Corning heat stirrer (Sigma-Aldrich).

[0226] Film thickness was measured using a step height measuring instrument (DektakXT, BRUKER), and transmittance and color conversion efficiency (PCE) were measured using a quantum efficiency measuring instrument (QE-2100, Otsuka Electronics).

[0227]

[0228] [Table 2]

[0229]

[0230] As shown in Table 2, in the case of Example 4, in which an upper layer containing quantum dots was coated with a protective composition containing one or more antioxidants, plasma resistance was improved from -7.05% to -5.92% during the PECVD process compared to Comparative Example 2 (Fig. 2).

[0231] In addition, the degradation rate in the second POB process after the PECVD process decreased from -3.81% to -0.7%, confirming improved thermal stability.

[0232]

[0233] [Example 5]

[0234] The procedure was carried out in the same manner as in Example 1, except that a high-refractive index monomer (BZA) was applied to the protective layer composition. The structure of the BZA used is as follows.

[0235]

[0236] Subsequently, a single film is deposited on a blue organic electroluminescent device, and 1000 cd / m² 2 The green light conversion brightness was measured by illuminating with light.

[0237]

[0238] [Comparative Example 3]

[0239] The procedure was carried out identically to Example 5, except that only the protective layer was excluded. After forming a single film using quantum dot ink and then placing the film produced by photocuring and thermal stabilization processes onto a blue organic electroluminescent device, 1000 cd / m² 2 The green light conversion brightness was measured by illuminating with light.

[0240]

[0241] [Example 6]

[0242] After performing high-purity sublimation purification using a commonly known method, a blue organic electroluminescent device was fabricated according to the following process. First, a glass substrate coated with a thin film of ITO (Indium tin oxide) to a thickness of 1200 Å was cleaned with distilled water ultrasonics. After the distilled water cleaning was finished, the substrate was ultrasonically cleaned with solvents such as isopropyl alcohol, acetone, and methanol, dried, transferred to a UV OZONE cleaner (Power sonic 405, Hwashin Tech), cleaned using UV light for 5 minutes, and then transferred to a vacuum deposition machine.

[0243] An organic electroluminescent device was fabricated by stacking HI + 2% HAT-CN6 (10 nm) / HI (140 nm) / EB (5 nm) / BH + 2% BD (20 nm) / ET-1 + Liq (1:1) (30 nm) / LiF (1 nm) / Al (100 nm) in that order on the ITO transparent electrode prepared as above. The structures of the materials used to fabricate the device are as follows.

[0244]

[0245]

[0246] [Experimental Example 3]

[0247] A single film to be measured was fixed to the upper layer of the blue organic electroluminescent device fabricated by the method according to Example 6 above, and light (blue light) was irradiated. Using an OLED IVL analyzer (YM-RTC), a luminance of 1000 cd / m² was measured. 2 The driving voltage, emission wavelength, and current efficiency (green light conversion brightness) were measured, and the results are shown in Table 3 and Figure 3 below.

[0248] [Table 3]

[0249]

[0250] When a high-refractive index protective layer (Example 5) was prepared and used in comparison to Comparative Example 3, it was confirmed that the green light conversion brightness increased due to the light extraction effect (out-coupling effect). In particular, it was found that the current efficiency improved from 4.0 to 4.4 in the blue light region, and the green light conversion brightness increased significantly (Fig. 4).

[0251]

[0252] Finally, the present invention stably realizes a low-viscosity, high-efficiency, planarized protective layer and significantly improves efficiency while simultaneously improving thermal process stability and lowering the degradation rate. When forming a thin film using quantum dots, it can be considered a desirable result if there is no difference between the efficiency after initial exposure and the efficiency after heat treatment.

[0253]

[0254] From the foregoing description, those skilled in the art to which the present invention pertains will understand that the present invention may be implemented in other specific forms without altering its technical concept or essential features. In this regard, the embodiments described above should be understood as illustrative in all respects and not restrictive. The scope of the present invention should be interpreted as including all modifications or variations derived from the meaning and scope of the claims set forth below and their equivalents, rather than from the detailed description above.

Claims

1. At least one curable monomer; and At least one antioxidant among compounds represented by the following chemical formulas 1 to 4; A composition for protecting inkjet printing films comprising: [Chemical Formula 1] [Chemical Formula 2] [Chemical Formula 3] [Chemical Formula 4] In the above chemical formulas 1 to 4, The above R' are identical or different from each other, and each independently C, O, S, N, substituted or unsubstituted C1-C 40 alkylene groups, substituted or unsubstituted C1-C 40 cycloalkylene groups, substituted or unsubstituted C1-C 40 alkyloxylene groups, substituted or unsubstituted C6-C 40 Selected from the group consisting of an arylene group or a substituted or unsubstituted heteroarylene group having 5 to 40 nuclei, The above R1 to R4 are identical or different from one another, and each independently hydrogen, hydroxyl group, acrylic group, halogen, cyano group, nitro group, C1-C 40 alkyl group of, C2-C 40 alkenyl group of, C2-C 40 alkynyl groups, substituted or unsubstituted C3-C 40 The cycloalkyl group of, and substituted or unsubstituted C6-C 60 It is selected from a group consisting of aryls, n is an integer from 1 to 4.

2. In Paragraph 1, The protective composition comprising 0.1 to 5 parts by weight of the antioxidant per 100 parts by weight of the total protective composition.

3. In Paragraph 1, The above antioxidant is a protective composition comprising at least one of the compounds represented by the following chemical formulas 5 and 6. [Chemical Formula 5] [Chemical Formula 6] 4. In Paragraph 1, The above-mentioned curable monomer comprises at least one of the monomers represented by the following chemical formulas 7 to 11 or oligomers thereof, and [Chemical Formula 7] [Chemical Formula 8] [Chemical Formula 9] [Chemical Formula 10] [Chemical Formula 11] In the above chemical formulas 7 to 11, The above R5, R7 and R 10 is a (meth)acrylate group, and The above R6, R8, R9, R 17 and R 18 They are identical or different from each other, and each independently hydrogen, hydroxyl group, acryl group, halogen, cyano group, nitro group, C1-C 40 alkyl group of, C2-C 40 alkenyl group of, C2-C 40 alkynyl groups, substituted or unsubstituted C3-C 40 cycloalkyl group of, C6-C 60 Selected from the group consisting of an aryl group and a substituted or unsubstituted heteroaryl group having 5 to 40 nuclei, The above R 11 to R 16 They are identical or different from one another, and each independently hydrogen, hydroxyl group, acrylic group, (meth)acrylate group, halogen, cyano group, nitro group, C1-C 40 alkyl group of, C2-C 40 alkenyl group of, C2-C 40 alkynyl groups, substituted or unsubstituted C3-C 40 The cycloalkyl group of, and substituted or unsubstituted C6-C 60 Selected from the group consisting of the aryl group of, wherein R 11 to R 16 One or more of them are (meth)acrylate groups, and m1 to m3 are identical or different from each other and are integers from 1 to 12, and m4 is an integer from 1 to 14, and The above Z is C, O, S, N, substituted or unsubstituted C1-C 40 alkylene groups, substituted or unsubstituted C1-C 40 cycloalkylene groups, substituted or unsubstituted C1-C 40 alkyloxylene groups, substituted or unsubstituted C6-C 40 It is selected from the group consisting of an arylene group or a substituted or unsubstituted heteroarylene group having 5 to 40 nuclei.

5. In Paragraph 1, A protective composition comprising 50 to 90 parts by weight of the above-mentioned curable monomer per 100 parts by weight of the total protective composition.

6. In Paragraph 1, A protective composition comprising one or more of the compounds represented by the following chemical formulas 12 to 14, wherein the above-mentioned curable monomer is a curable monomer. [Chemical Formula 12] [Chemical Formula 13] [Chemical Formula 14] 7. In Paragraph 1, The above protective composition further comprises a high-refractive monomer represented by the following chemical formula 15: [Chemical Formula 15] In the above chemical formula 15, The above X are identical or different from one another, and each independently hydrogen, hydroxyl group, acrylic group, cyano group, nitro group, C1-C 40 alkyl group of, C2-C 40 alkenyl group of, C2-C 40 alkynyl groups, substituted or unsubstituted C6-C 40 Selected from the group consisting of an aryl group and a substituted or unsubstituted heteroaryl group having 5 to 40 nuclear atoms, The above Y is hydrogen, hydroxyl group, acrylic group, cyano group, nitro group, C1-C 40 alkyl group of, C2-C 40 alkenyl group of, C2-C 40 alkynyl groups, substituted or unsubstituted C6-C 40 Selected from the group consisting of an aryl group and a substituted or unsubstituted heteroaryl group having 5 to 40 nuclear atoms, m5 is an integer from 0 to 12, and The above A are identical or different from each other and are C, O, S or N.

8. In Paragraph 7, The above Y is a protective composition having one of the following structural formulas: In this case, * represents the site that binds to Y in chemical formula 15.

9. In Paragraph 1, The above composition is a protective composition having a viscosity of 10 to 50 cps at 25°C and being solvent-free.

10. A protective layer comprising a cured product of a protective composition according to any one of claims 1 to 9.

11. In Paragraph 10, The protective layer has a thickness of 0.1 to 10 μm.

12. In Paragraph 10, The above protective layer is a protective layer having a refractive index of 1.4 or higher.

13. Substrate; lower layer; As an image display device including an upper layer, The above substrate includes a light source, and The above lower layer includes a color conversion layer, and The above upper layer is an image display device comprising the protective layer of claim 10.

14. In Paragraph 13, An image display device in which the above-mentioned lower layer includes quantum dots.

15. In Paragraph 13, An image display device comprising one or more layers selected from the group consisting of an organic layer, an inorganic layer, and an organic-inorganic composite layer, wherein the upper layer comprises 16. In Paragraph 13, The above light source is an image display device including a blue light source.

17. In Paragraph 14, The above image display device is a flexible image display device.

18. Step of providing a substrate; A step of forming a lower layer on the above substrate; and A method for manufacturing an image display device comprising the step of forming an upper layer on the lower layer, The step of forming the lower layer includes an inkjet printing process and a curing process, and A manufacturing method comprising the step of forming the upper layer, a process of treating the lower layer with a protective composition according to any one of claims 1 to 9, and a curing process.

19. In Paragraph 18, A manufacturing method further comprising a thermal stabilization process of 100 to 200℃.

20. In Paragraph 18 or 19, A manufacturing method in which the step of forming the upper layer further includes a chemical vapor deposition process.

21. In Paragraph 20, A manufacturing method wherein the chemical vapor deposition process further comprises a thermal stabilization process of 100 to 200°C.

22. In Paragraph 20, The above chemical vapor deposition process is a plasma enhanced chemical vapor deposition (PECVD) process, a manufacturing method.

23. In Paragraph 18, A manufacturing method in which the above curing process is a photocuring or thermal curing process.

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