TWI500703B - Photo-curing coating composition, photo-curing coating film and touch panel - Google Patents

Description

Photocurable coating composition, photocurable coating film, and touch panel

The present invention relates to a photocurable coating composition, and more particularly to a photocurable coating composition containing a photo-curable polymer obtained by subjecting a metal alkoxide to a water-condensing condensation reaction, and the light-curable coating composition A photo-curing coating film obtained by the curable coating composition and a touch panel including the photo-curing coating film.

In the touch liquid crystal display device, an overcoat layer is usually disposed on the sensing element of the touch panel to protect the underlying member, thereby improving the reliability of the touch liquid crystal display device. In general, due to the significant difference in refractive index between different material layers, this will result in the user easily seeing the pattern of the sensing element, thereby reducing the visibility and display quality of the touch liquid crystal display device. At present, the related research is to reduce the difference between the refractive indexes and improve the visibility by providing a Nb ₂ O ₅ layer under the protective layer. However, this method can improve the visibility and increase the process steps and costs. Therefore, it has become an industry to provide a coating film which has both a general protective layer and a Nb ₂ O ₅ layer to achieve an effect of high refractive index, high transmittance, good protection, and good visibility. The subject of eager research.

The present invention provides a photocurable coating composition which has good photocurability, a photocurable coating film formed of the photocurable coating composition, which has a good refractive index and a transmittance, and is suitable for Applied to the touch panel.

The photocurable coating composition of the present invention includes a photocurable polymer. The photocurable polymer is obtained by subjecting at least a metal alkoxide represented by the formula (I), a metal alkoxide represented by the formula (II) and a metal alkoxide represented by the formula (III) to hydrolysis and condensation reaction: R ^a ₁ Si(OR ^b ) ₃ Formula (I); R ^c ₁ Si(OR ^d ) ₃ Formula (II); Ti(OR ^e ) ₄ Formula (III); wherein R ^a represents aroma of 6-15 a group, R ^b represents an alkyl group having 1 to 5 carbon atoms, R ^c represents an alkenyl group having 2 to 10 carbon atoms, R ^d represents an alkyl group having 1 to 5 carbon atoms, and R ^e represents an alkyl group having 1 to 5 carbon atoms. And the total amount of the metal alkoxide represented by the formula (I), the metal alkoxide represented by the formula (II) and the metal alkoxide represented by the formula (III) is 100 parts by weight, and the formula (I) The metal alkoxide is shown in an amount of 25 parts by weight to 50 parts by weight, and the metal alkoxide represented by the formula (II) is contained in an amount of 5 parts by weight to 20 parts by weight, and the metal alkoxide is represented by the formula (III). The content of the substance is from 45 parts by weight to 70 parts by weight.

In one embodiment of the present invention, the total amount of the metal alkoxide represented by the above formula (I), the metal alkoxide represented by the formula (II), and the metal alkoxide represented by the formula (III) is The content of the metal alkoxide represented by the formula (I) is from 25 parts by weight to 45 parts by weight per 100 parts by weight.

In one embodiment of the present invention, the total amount of the metal alkoxide represented by the above formula (I), the metal alkoxide represented by the formula (II), and the metal alkoxide represented by the formula (III) is The content of the metal alkoxide represented by the formula (I) is from 30 parts by weight to 40 parts by weight per 100 parts by weight.

In an embodiment of the invention, the photocurable coating composition further includes a solvent.

The photocurable coating composition of the present invention includes a photocurable polymer. The photocurable polymer is obtained by substantially hydrolyzing a condensation reaction of a metal alkoxide represented by the formula (II) and a metal alkoxide represented by the formula (III): R ^c ₁ Si(OR ^d ) ₃ (II); Ti(OR ^e ) ₄ Formula (III); wherein R ^c represents an alkenyl group having 2 to 10 carbon atoms, R ^d represents an alkyl group having 1 to 5 carbon atoms, and R ^e represents an alkane having 1 to 5 carbon atoms; And the content of the metal alkoxide represented by the formula (III) is 100 parts by weight based on 100 parts by weight of the total amount of the metal alkoxide represented by the formula (II) and the metal alkoxide represented by the formula (III). 55 parts by weight to 70 parts by weight.

In an embodiment of the invention, the photocurable coating composition further includes a solvent.

The photo-curing coating film of the present invention is produced from the photocurable coating composition as described above.

In an embodiment of the invention, the photo-curing coating film has a film thickness of 80 nm to 120 nm and a refractive index of 1.60 to 1.70.

In an embodiment of the invention, the light-curing coating film has a transmittance of more than 95% in a wavelength range of 380 nm to 450 nm.

The touch panel of the present invention includes the photo-curing coating film as described above.

Based on the above, the photocurable coating composition of the present invention comprises at least a metal alkoxide represented by the formula (I), a metal alkoxide represented by the formula (II), and a formula (III). A photocurable polymer obtained by reacting a metal alkoxide. The photocurability of the present invention is attained by the content of the metal alkoxide represented by the formula (I), the metal alkoxide represented by the formula (II), and the metal alkoxide represented by the formula (III) within the above range. The coating composition has good photocurability, and a light-curing coating film having a good refractive index and transmittance can be obtained. Another photocurable coating composition according to the present invention, which comprises a photohardening reaction consisting essentially of a metal alkoxide represented by the formula (II) and a metal alkoxide represented by the formula (III) Sexual aggregation Things. When the content of the metal alkoxide represented by the formula (II) and the metal alkoxide represented by the formula (III) is within the above range, the photocurable coating composition of the present invention has good photocurability and can be A photo-curing coating film having a good refractive index was obtained. As a result, the touch panel using the photo-curing coating film of the present invention can have good visibility and display quality.

The above described features and advantages of the invention will be apparent from the following description.

100‧‧‧ touch panel

102‧‧‧Substrate

104‧‧‧Touch components

106‧‧‧Protective layer

110, 120‧‧‧ Touch series

112, 122‧‧‧ touch electrodes

114, 124‧‧‧ Connections

130‧‧‧Insulation pattern

D1, D2‧‧‧ direction

1 is a top plan view of a touch panel according to an embodiment of the present invention.

2 is a cross-sectional view of the touch panel of FIG. 1 taken along line I-I'.

In the present specification, the range represented by "a value to another value" is a schematic representation that avoids enumerating all the values in the range in the specification. Therefore, the recitation of a particular range of values is intended to include any value in the range of values and the range of values defined by any value in the range of values, as in the specification. The scope is the same.

In order to prepare a photoharden coating with good refractive index and transmittance The film is suitable for use in a touch panel, and the present invention proposes a photocurable coating composition having good photocurability which can attain the above advantages. Hereinafter, the specific embodiments are described as examples in which the present invention can be implemented.

A photocurable coating composition according to an embodiment of the present invention includes a photocurable polymer. The photocurable polymer is obtained by subjecting at least a metal alkoxide represented by the formula (I), a metal alkoxide represented by the formula (II) and a metal alkoxide represented by the formula (III) to hydrolysis and condensation reaction: R ^a ₁ Si(OR ^b ) ₃ Formula (I); R ^c ₁ Si(OR ^d ) ₃ Formula (II); Ti(OR ^e ) ₄ Formula (III); wherein R ^a represents aroma of 6-15 Further, R ^b represents an alkyl group having 1 to 5 carbon atoms, R ^c represents an alkenyl group having 2 to 10 carbon atoms, R ^d represents an alkyl group having 1 to 5 carbon atoms, and R ^e represents an alkyl group having 1 to 5 carbon atoms.

In detail, in the definition of R ^a , the aryl group is, for example but not limited to, phenyl, tolyl, p-hydroxyphenyl, 1-(p-hydroxyphenyl)ethyl, 2-(p-hydroxyl) Phenyl)ethyl, 4-hydroxy-5-(p-hydroxyphenylcarbonyloxy)pentyl or naphthyl; definition of R ^b In the alkyl group, for example, but not limited to, methyl, ethyl, n-propyl, isopropyl or n-butyl; in the definition of R ^c , alkenyl group such as, but not limited to, vinyl, 3-propenyloxypropyl Or 3-methacryloxypropyl; in the definition of ^Rd , alkyl is, for example but not limited to, methyl, ethyl, n-propyl, isopropyl or n-butyl; and in the definition of R ^e Alkyl groups are, for example but not limited to, methyl, ethyl, n-propyl, isopropyl or n-butyl.

Examples of the metal alkoxide represented by the formula (I) include, but are not limited to, phenyl trimethoxysilane, phenyl triethoxysilane, p-hydroxyphenyltrimethoxydecane ( P-hydroxyphenyl trimethoxysilane), 1-(p-hydroxyphenyl)ethyl trimethoxysilane, 2-(p-hydroxyphenyl)ethyltrimethoxydecane (2) -(p-hydroxyphenyl)ethyl trimethoxysilane), 4-hydroxy-5-(p-hydroxyphenylcarbonyloxy)pentyl trimethoxysilane. Further, examples of commercially available products suitable for use as the metal alkoxide represented by the formula (I) include: KBM-103 or KBE-103 (manufactured by Shin-Etsu Chemical Co., Ltd.). In one embodiment, the metal alkoxide of formula (I) is phenyltrimethoxydecane.

Examples of the metal alkoxide represented by the formula (II) include, but are not limited to, vinyl trimethoxysilane, vinyl triethoxysilane, 3-propenyloxypropyltrimethoxysilane. 3-acryoyloxypropyl trimethoxysilane, 3-methylacryloyloxypropyl trimethoxysilane Or 3-methylacryloyloxypropyl triethoxysilane. Further, examples of commercially available products suitable for use as the metal alkoxide represented by the formula (II) include: KBM-1003, KBE-1003, KBM-503, KBE-503, and KBM-5103 (manufactured by Shin-Etsu Chemical Co., Ltd.) . In one embodiment, the metal alkoxide of formula (II) is 3-methylpropenyloxypropyltrimethoxydecane.

Examples of the metal alkoxide represented by the formula (III) include, but are not limited to, titanium tetramethoxide, titanium tetraethoxide, titanium tetra-n-propoxide, titanium tetraisopropoxide or titanium tetra-n-butoxide. Further, examples of commercially available products suitable for use as the metal alkoxide represented by the formula (III) include: TPT or TBT (manufactured by Nippon Soda Co., Ltd.). In one embodiment, the metal alkoxide of formula (III) is tetra-n-butoxytitanium.

In the present embodiment, the total amount of the metal alkoxide represented by the formula (I), the metal alkoxide represented by the formula (II), and the metal alkoxide represented by the formula (III) is 100 parts by weight. The content of the metal alkoxide represented by the formula (I) is from 25 parts by weight to 50 parts by weight, preferably from 25 parts by weight to 45 parts by weight, more preferably from 30 parts by weight to 40 parts by weight. When the content of the metal alkoxide represented by the formula (I) is less than 25 parts by weight, the transmittance of the photohardenable coating film prepared from the photocurable coating composition in the wavelength range of 380 nm to 450 nm difference. When the content of the metal alkoxide represented by the formula (I) is more than 50 parts by weight, the photocurable coating film obtained from the photocurable coating composition is in the range of the wavelength of 380 nm to 450 nm. The penetration rate is good, but there will be serious yellowing problems.

In the present embodiment, the total amount of the metal alkoxide represented by the formula (I), the metal alkoxide represented by the formula (II), and the metal alkoxide represented by the formula (III) is 100 parts by weight. The metal alkoxide represented by the formula (II) is contained in an amount of from 5 parts by weight to 20 parts by weight. When the content of the metal alkoxide represented by the formula (II) is less than 5 parts by weight, the photocurable coating composition is inferior in photocurability. When the content of the metal alkoxide represented by the formula (II) is more than 20 parts by weight, although the photocurable coating composition has good photocurability, the photohardenable coating prepared from the photocurable coating composition is used. The refractive index of the film is not good, or the transmittance of the photo-curing coating film is not good in the range of 380 nm to 450 nm.

In the present embodiment, the total amount of the metal alkoxide represented by the formula (I), the metal alkoxide represented by the formula (II), and the metal alkoxide represented by the formula (III) is 100 parts by weight. The metal alkoxide represented by the formula (III) is contained in an amount of from 45 parts by weight to 70 parts by weight. When the content of the metal alkoxide represented by the formula (III) is less than 45 parts by weight, the refractive index of the photohardenable coating film produced from the photocurable coating composition is too small. When the content of the metal alkoxide represented by the formula (III) is more than 70 parts by weight, the photocurable coating composition is inferior in photocurability, and photoharden coating by the photocurable coating composition is obtained. The refractive index of the film is too large, or in the range of wavelengths of 380 nm to 450 nm, the transmittance of the photo-curing coating film is not good.

The effect range of the photocurable coating composition of the present invention is not impaired In the photocurable coating composition, the photocurable polymer is a metal alkoxide represented by the above formula (I), a metal alkoxide represented by the formula (II), and a metal alkane represented by the formula (III). In addition to the oxide, other metal alkoxides may also be obtained by hydrolysis and condensation reaction. The other metal alkoxides include, but are not limited to, 3-glycidoxypropyl trimethoxysilane, 3-glycidoxypropyl triethoxysilane , 2-(3,4-epoxycyclohexyl)ethyl trimethoxysilane, 3-ethyl-3-((3-(triphenyloxy)) 3-ethyl-3-((3-(triphenoxysilyl)propoxy)methyl)oxetane), 3-ethyl-3-((3-(trimethoxy) oxime) 3-ethyl-3-((3-(trimethoxysilyl)propoxy)methyl)oxetane), 3-ethyl-3-((3-(triethoxy) oxime) 3-ethyl-3-((3-(triethoxysilyl)propoxy)methyl)oxetane), 2-(trimethoxyindenyl)ethyl succinic anhydride (2- (trimethoxysilyl)ethyl succinic anhydride), 3-(triphenoxysilyl)propyl succinic anhydride, 3-(trimethoxyindolyl)propyl succinic anhydride (3) -(trimethoxysilyl)propyl succinic anhydride), 3-(triethoxysilyl)propyl succinic anhydride (3-(triethoxysilyl) propyl Succinic anhydride), 3-(trimethoxyanthracene) 3-(trimethoxysilyl)propyl glutaric anhydride, 3-(triethoxysilyl)propyl glutaric anhydride, 3-(triphenyloxy) 3-(triphenoxysilyl)propyl glutaric anhydride, diisopropoxy-di(2-oxetanylpropylbutoxypropyl) Silane), di(3-oxetanylpentyl)dimethoxy silane, (di-n-butoxycarbonyl)di(propyl succinic anhydride) (di -n-butoxysilyl)di(propyl succinic anhydride), (dimethoxysilyl) di(ethyl succinic anhydride), 3-epoxypropoxy dimethyl 3-glycidoxydimethylmethoxysilane, 3-glycidoxydimethylethoxysilane, bis(2-propylene oxide-butoxypentyl)-2-epoxy Di(2-oxetanylbutoxypentyl)-2-oxetanylpentylethoxy silane, tri(2-oxetanylpentyl)methoxy s Ilane), (phenoxysilyl) tri(propyl succinic anhydride), (methylmethoxyindolyl) di(ethyl succinic anhydride) ((methylmethoxysilyl) ) Di(ethyl succinic anhydride)), tetramethoxysilane, tetraethoxysilane, tetraacetoxysilane, tetraphenoxysilane, methyltrimethoxy Methyltrimethoxysilane, methyltriethoxysilane, methyltriisopropoxysilane, methyltri-n-butoxysilane, ethyltrimethoxydecane (ethyltrimethoxysilane), ethyltriethoxysilane, ethyltriisopropoxysilane, ethyltri-n-butoxysilane, n-propyltrimethoxydecane (n-propyltrimethoxysilane), n-propyltriethoxysilane, n-butyltrimethoxysilane, n-butyltriethoxysilane, n-hexyltrimethyl N-hexyltrimethoxysilane, n-hexyltriethoxysilane, decyltrimethoxysilane Trifluoromethyl trimethoxy Silane (trifluoromethyltrimethoxysilane), trifluoromethyl triethoxy silane- (trifluoromethyltriethoxysilane), 3,3,3-trifluoropropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane 3-aminopropyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldiacetyloxysilane, di-n-butyl Di-n-butyldimethoxysilane, diphenyldimethoxysilane, trimethylmethoxysilane, tri-n-butylethoxysilane , 3-mercaptopropyltrimethoxysilane.

A photocurable coating composition provided by another embodiment of the present invention includes a photocurable polymer. The photocurable polymer is obtained by substantially hydrolyzing a condensation reaction of a metal alkoxide represented by the formula (II) and a metal alkoxide represented by the formula (III): R ^c ₁ Si(OR ^d ) ₃ (II); Ti(OR ^e ) ₄ Formula (III); wherein R ^c represents an alkenyl group having 2 to 10 carbon atoms, R ^d represents an alkyl group having 1 to 5 carbon atoms, and R ^e represents an alkane having 1 to 5 carbon atoms; base.

Examples of the metal alkoxide represented by the formula (II) and the metal alkoxide represented by the formula (III) include the examples as exemplified above.

In the present embodiment, the metal alkoxide represented by the formula (III) is a total amount of the metal alkoxide represented by the formula (II) and the metal alkoxide represented by the formula (III) in an amount of 100 parts by weight. The content is from 55 parts by weight to 70 parts by weight. When the content of the metal alkoxide represented by the formula (III) is less than 55 parts by weight, the refractive index of the photohardenable coating film produced from the photocurable coating composition is too small. When the content of the metal alkoxide represented by the formula (III) is more than 70 parts by weight, the photocurable coating composition is inferior in photocurability, and photoharden coating by the photocurable coating composition is obtained. The refractive index of the film is too large.

In the foregoing embodiment, the hydrolysis method can be carried out by a general method. For example, a metal alkoxide represented by the formula (I), a metal alkoxide represented by the formula (II), and a metal alkoxide represented by the formula (III) are contacted with a solvent, water or a selective addition. The medium is heated and stirred at 30 ° C to 150 ° C for 0.5 hour to 120 hours. Further, by stirring, by-products (alcohols, water, etc.) can be further removed by distillation.

The above solvent is not particularly limited and may be the same as or different from the solvent used in the photocurable coating composition of the present invention (the related description will be described later). The total amount of the metal alkoxide represented by the formula (I), the metal alkoxide represented by the formula (II) and the metal alkoxide represented by the formula (III) is 100 g, and the solvent is used. The amount is preferably from 100 g to 1,200 g, more preferably from 300 g to 1,000 g.

The hydrolyzable group contained in the metal alkoxide represented by the formula (I), the metal alkoxide represented by the formula (II) and the metal alkoxide represented by the formula (III) is 1 mol. The amount of water used for hydrolysis is from 0.5 moles to 2 moles.

The above catalyst is not particularly limited. In one embodiment, the catalyst is selected from an acid catalyst or a base catalyst. The acid catalyst includes, but is not limited to, oxalic acid, hydrochloric acid, nitric acid, sulfuric acid, hydrofluoric acid, phosphoric acid, acetic acid, trifluoroacetic acid, formic acid, polycarboxylic acid or anhydride thereof, ion exchange resin, and the like. The base catalyst includes, but is not limited to, diethylamine, triethylamine, tripropylamine, tributylamine, triamylamine, trihexylamine, triheptylamine, trioctylamine, diethanolamine, triethanolamine, sodium hydroxide, Potassium hydroxide, an alkoxysilane containing an amine group, an ion exchange resin, and the like. The total amount of the catalyst is compared with the total amount of the metal alkoxide represented by the formula (I), the metal alkoxide represented by the formula (II) and the metal alkoxide represented by the formula (III). Preferably, it is from 0.005 g to 15 g, more preferably from 0.01 g to 12 g, still more preferably from 0.05 g to 10 g.

From the viewpoint of stability, the photocurable polymer obtained by the hydrolysis reaction is preferably free from by-products (such as alcohols or water) and a catalyst, so that it can be selectively hydrolyzed and condensed. The photohardenable polymer is purified. The purification method is not particularly limited. In one embodiment, the photocurable polymer may be diluted with a hydrophobic solvent, followed by concentration of the organic layer washed several times with water by an evaporator to remove the alcohol or water. Alternatively, the catalyst can be removed using an ion exchange resin.

Further, in the present embodiment, the photocurable coating composition may further include a solvent. The kind of the solvent is not particularly limited. In detail, the solvent includes, but is not limited to, a compound containing an alcoholic hydroxyl group or a cyclic compound containing a carbonyl group. Further, the solvent may be used singly or in combination.

The alcoholic hydroxyl group-containing compound includes, but is not limited to, acetol, 3-hydroxy-3-methyl-2-butanone, 4-hydroxy-3-methyl-2-butanone, 5-hydroxy- 2-pentanone, 4-hydroxy-4-methyl-2-pentanone (also known as diacetone alcohol), ethyl lactate, butyl lactate, propylene glycol monomethyl ether, propylene glycol monoethyl ether ), propylene glycol monomethylether acetate, propylene glycol mono-n-propyl ether, propylene glycol mono-n-butyl ether, propylene glycol mono-tert-butyl ether, 3-methoxy-1-butanol, 3-methyl-3 -Methoxy-1-butanol or a combination of these. The alcoholic hydroxyl group-containing compound is preferably selected from the group consisting of diacetone alcohol, ethyl lactate, propylene glycol monoethyl ether, propylene glycol methyl ether acetate, or a combination thereof.

The carbonyl group-containing cyclic compound includes, but is not limited to, γ-butyrolactone, γ-valerolactone, δ-valerolactone, propylene carbonate, nitrogen-methylpyrrolidone, cyclohexanone or cycloheptanone. The carbonyl-containing cyclic compound is preferably selected from the group consisting of γ-butyrolactone, nitrogen-methylpyrrolidone, cyclohexanone, or a combination thereof.

When the compound having an alcoholic hydroxyl group is used in combination with a cyclic compound containing a carbonyl group, the weight ratio thereof is not particularly limited. In one embodiment, the alcoholic form The weight of the hydroxy compound and the carbonyl group-containing cyclic compound is preferably from 99/1 to 50/50, more preferably from 95/5 to 60/40.

The photocurable coating composition may contain other solvents within the range of the effect of not impairing the photocurable coating composition of the present invention. The other solvents include, but are not limited to, (1) esters: ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, propylene glycol methyl ether acetate, 3-methoxy- 1-butyl acetate, 3-methyl-3-methoxy-1-butyl acetate, etc.; (2) ketones: methyl isobutyl ketone, diisopropanone, diisobutyl ketone, etc.; (3) ether Class: diethyl ether, diisopropyl ether, di-n-butyl ether, diphenyl ether and the like.

Further, the solvent is used in an amount of from 500 parts by weight to 20,000 parts by weight, based on the total amount of the photocurable polymer, preferably from 800 parts by weight to 10,000 parts by weight, more preferably from 1,000 parts by weight to 6,000 parts by weight. Share.

The photocurable coating composition may be added with other additives as needed within the range of the effect of not impairing the photocurable coating composition of the present invention. The additives may be used singly or in combination, and the additives include, but are not limited to, sensitizers, adhesion promoters, surfactants, dissolution promoters, antifoaming agents, or a combination thereof.

A photo-curing coating film according to an embodiment of the present invention is produced by the photocurable coating composition of any of the above embodiments. In detail, the method for preparing the photo-curable coating film includes sequentially applying a photo-curable coating composition onto a substrate, performing a pre-bake treatment to form a pre-baked coating film, and The prebaked coating film is subjected to photohardening treatment and post-bake treatment.

The method of applying the photocurable coating composition can be carried out by a coating method generally performed, for example, a dip coating method, a spin coating method, a spray coating method, a brush coating method, a roll transfer method, a screen printing method, or a spray method. Ink method or offset printing method. The substrate may be alkali-free glass, soda-lime glass, hard glass (Pyrus glass), quartz glass, or the above-described glass to which a transparent conductive film is attached. In one embodiment, the transparent conductive film is, for example, a touch element of a touch panel.

The temperature condition of the pre-baking treatment is preferably from room temperature to 150 ° C, more preferably from 40 ° C to 120 ° C. The time condition of the pre-baking treatment is preferably from about 30 seconds to about 10 minutes, more preferably from about 1 minute to about 8 minutes. As the method of the pre-baking treatment, for example, a hot plate or a hot air circulation type oven or the like can be used.

The light used in the photohardening treatment is preferably ultraviolet rays such as g-line, b-line, or i-line, and the device for providing ultraviolet rays may be a (ultra) high pressure mercury lamp or a metal halide lamp.

The temperature condition of the post-baking treatment is preferably from 100 ° C to 300 ° C, more preferably from 150 ° C to 250 ° C. The time condition of the post-baking treatment is preferably 5 minutes or longer, more preferably 15 minutes or longer. For the post-baking treatment, for example, a hot plate, a hot air circulating oven, an infrared oven, or the like can be used.

In one embodiment, the photohardenable coating film of the present invention has a film thickness of from 80 nm to 120 nm and a refractive index of from 1.60 to 1.70.

In one embodiment, the light-curable coating film of the present invention has a transmittance of greater than 95% in the range of wavelengths of 380 nm to 450 nm.

In addition, the photocurable coating film of the present invention containing a metal alkoxide (inorganic material) as a main component has superior mechanical strength as compared with a coating film which is generally composed of an organic material, and is suitable for use in the following description. The touch panel of the present invention.

A touch panel according to an embodiment of the present invention includes the photo-curing coating film according to any of the foregoing embodiments. Hereinafter, the touch panel of the present invention will be described in detail with reference to FIGS. 1 and 2.

1 is a top plan view of a touch panel according to an embodiment of the present invention. 2 is a cross-sectional view of the touch panel of FIG. 1 taken along line I-I'. Referring to FIG. 1 and FIG. 2 , the touch panel 100 includes a substrate 102 , a touch element 104 , and a protective layer 106 .

Substrate 102 can be any substrate known in the art, such as a germanium substrate, a glass substrate, a plastic substrate, or other flexible substrate.

The touch element 104 is disposed on the substrate 102. In this embodiment, the touch component 104 includes a plurality of touch strings 110 and a plurality of touch strings 120, wherein the touch string 110 extends along the direction D1, and the touch string 120 intersects the direction D1. The direction D2 extends, and the touch string 110 and the touch string 120 Electrically insulated from each other. In detail, each touch string 110 includes a plurality of touch electrodes 112 and a plurality of connecting portions 114. Each of the connecting portions 114 connects two adjacent touch electrodes 112, and each touch string 120 includes multiple touches. The control electrode 122 and the plurality of connecting portions 124 are connected to the adjacent two touch electrodes 122. In addition, an insulation pattern 130 is disposed at the intersection of the touch string 110 and the touch string 120 to electrically insulate the two.

The material of the touch electrode 112 and the connecting portion 114 of the touch string 110 and the touch electrode 122 and the connecting portion 124 of the touch string 120 may be the same or different, and is, for example, a transparent conductive material or other suitable conductive material. The transparent conductive material is, for example, indium tin oxide, indium zinc oxide, aluminum zinc oxide, or the like, and a mixture or laminate thereof.

In addition, in the present embodiment, the touch element 104 having the structure shown in FIGS. 1 and 2 is taken as an example, but the invention is not limited thereto. Touch element 104 can be any touch element known to those of ordinary skill in the art. That is, touch element 104 can have other configurations as are well known.

The protective layer 106 is disposed on the substrate 102 and covers the touch element 104 for protecting the touch element 104 from external force. In the present embodiment, the protective layer 106 is realized by the photo-curing coating film of any of the above embodiments. That is, the protective layer 106 is transmitted through the photocurable coating group of the present invention. After the application is applied to the touch element 104, it is formed by prebaking, photohardening, and post-baking. However, the related description and preparation method of the photo-curing coating film have been described in detail in the foregoing embodiments, and thus will not be described herein.

It is to be noted that, as described above, the photo-curing coating film of the present invention has a refractive index of between 1.60 and 1.70, and a transmittance of more than 95% in the wavelength range of 380 nm to 450 nm, thereby The light-curing coating film of the present invention can have good visibility and display quality as a touch panel of a protective layer.

<experiment>

The photocurable coating composition of the present invention will be more specifically described below with reference to experimental examples. Although the following experiments are described, the materials used, the amounts and ratios thereof, the processing details, the processing flow, and the like can be appropriately changed without departing from the scope of the invention. Therefore, the invention should not be construed restrictively based on the experiments described below.

Experimental example 1 Preparation of photocurable polymer

In a three-necked flask having a volume of 1,000 ml, 25 parts by weight of phenyltrimethoxydecane (hereinafter referred to as PTMS, that is, a metal alkoxide represented by the formula (I)), and 11 parts by weight of 3-methylpropene were added.醯 propyl trimethoxy decane (hereinafter referred to as KBM 503, that is, a metal alkoxide represented by formula (II)), 64 parts by weight Tetra-n-butoxytitanium (hereinafter referred to as TBT, that is, metal alkoxide represented by formula (III)) [all of the above metal alkoxides have a total weight of 100 g] and 600 g of propylene glycol monoethyl ether (hereinafter referred to as PGEE) And, an aqueous oxalic acid solution (0.40 g of oxalic acid / 75 g of water) was added over 30 minutes while stirring at room temperature. Next, the flask was immersed in an oil bath at 30 ° C and stirred for 30 minutes, and then the oil bath was heated to 120 ° C in 30 minutes. When the internal temperature of the solution reached 105 ° C, heating and stirring were continued for polycondensation for 6 hours. The photocurable polymer of Experimental Example 1 was obtained by removing the solvent by distillation.

Preparation of photocurable coating composition

100 parts by weight of the photocurable polymer of Experimental Example 1 and 1,900 parts by weight of PGEE were uniformly stirred by a shaking stirrer to obtain a photocurable coating composition of Experimental Example 1 (solid content: 5 weight) %).

Experimental Example 2 to Experimental Example 6

The photocurable coating compositions of Experimental Examples 2 to 6 were prepared in the same manner as Experimental Example 1. The difference is that when the photocurable polymer of Experimental Example 2 to Experimental Example 6 is prepared, the metal alkoxide represented by the formula (I), the metal alkoxide represented by the formula (II) or the formula (III) The kind or amount of the metal alkoxide is different from that of Experimental Example 1, and the details thereof are shown in Table 1.

Experimental example 7

The photocurable coating of Experimental Example 7 was prepared in the same manner as Experimental Example 1. Cloth composition. The difference is that when the photocurable polymer of Experimental Example 7 is prepared, in addition to the metal alkoxide represented by the formula (I), the metal alkoxide represented by the formula (II) or the metal alkoxide represented by the formula (III) The kind or amount of the substance was different from that of Experimental Example 1 (details are detailed in Table 1), and 3 parts by weight of tetraethoxysilane (hereinafter referred to as TEOS) was further added.

Experimental Example 8

The photocurable coating composition of Experimental Example 8 was prepared in the same manner as Experimental Example 1. The difference is that when the photocurable polymer of Experimental Example 8 is prepared, the metal alkoxide represented by the formula (I), the metal alkoxide represented by the formula (II) and the metal represented by the formula (III) are not used. The amount of alkoxide used was different from that of Experimental Example 1, and the details thereof are shown in Table 1.

Comparative Example 1 to Comparative Example 7

The photocurable coating compositions of Comparative Examples 1 to 7 were prepared in the same manner as Experimental Example 1. The difference is that when the photocurable polymer of Comparative Example 1 to Comparative Example 7 is prepared, the metal alkoxide represented by the formula (I), the metal alkoxide represented by the formula (II) or the formula (III) The type or amount of the metal alkoxide is different from that of Experimental Example 1, and the details thereof are shown in Table 2.

Comparative Example 8

The photocurable coating composition of Comparative Example 8 was prepared in the same manner as Experimental Example 1. The difference is that when the photocurable polymer of Comparative Example 8 was prepared, The metal alkoxide represented by the formula (I) is used, but TEOS is added. The type and amount of the metal alkoxide represented by the formula (II) used in the comparative example 8 and the metal alkoxide represented by the formula (III) and the amount of TEOS added are shown in Table 2.

Next, the photocurable coating compositions of Experimental Examples 1 to 8 and Comparative Examples 1 to 8 were each prepared into a photocurable coating film, and the detailed procedure was as follows. First, the photocurable coating compositions of Experimental Examples 1 to 8 and Comparative Examples 1 to 8 were separately filtered under pressure with a membrane filter having a pore diameter of 0.5 μm, and coated on a substrate by spin coating. A pre-baked coating film is formed. Next, the substrate on which the prebaked coating film was formed was placed on a hot plate set to a temperature of 90 ° C, and dried by heating for 5 minutes. Thereafter, ultraviolet rays were irradiated for 75 seconds at a light intensity of 16 mW/cm ² (wavelength 365 nm) with a high-pressure mercury lamp (input power supply 1000 W) using an ultraviolet irradiation device (manufactured by Eye Graphics Co., Ltd., model: UB 011-3A), wherein the ultraviolet irradiation amount was 1200mJ/cm ² . After the ultraviolet irradiation, the substrate was transferred to a hot air circulating oven set to a temperature of 250 ° C, and post-baked for 30 minutes to form light of Experimental Example 1 to Experimental Example 8 and Comparative Example 1 to Comparative Example 8 on the substrate. Hardened coating film (film thickness: 100 nm).

Thereafter, the photo-curing coating films of Experimental Examples 1 to 8 and Comparative Examples 1 to 8 were evaluated by the following test methods, and the evaluation results thereof are shown in Tables 1 and 2.

testing method

Photocurability: After the photocurable coating films of Experimental Examples 1 to 8 and Comparative Examples 1 to 8 were obtained, each of the photocurable coating films was observed with the naked eye to evaluate the light of the photocurable coating composition. The hardening property was evaluated as follows: ○: the surface of the coating film was smooth; ×: the surface of the coating film was uneven or broken.

Refractive index test: The photohardenable coating films of Experimental Examples 1 to 8 and Comparative Examples 1 to 8 were measured at a wavelength of 550 nm using a film measuring instrument (manufactured by Mission Peak Optics Inc., model: MP100-ST). Refractive index. When applied to a general touch panel, the standard of the refractive index is at least greater than 1.6, and more preferably between 1.6 and 1.7.

Penetration test: The photohardenable coating films of Experimental Examples 1 to 7 and Comparative Examples 1 to 8 were measured for the wavelength range of 380 nm to 450 nm using a UV/Vis spectrometer (manufactured by Hitachi, model: U3300). The permeability is evaluated as follows: ○: penetration rate ≧ 95%; ×: penetration rate < 95%.

Yellowing test: The photohardening coating films of Experimental Examples 1 to 7 and Comparative Examples 1 to 8 were placed on a black cloth, and the light hardening coating formed by visual observation was observed in a state illuminated by the upper fluorescent lamp. The film is evaluated as follows: ○: the transparency is slightly yellow; ×: Severe yellowing.

It is worth noting that in Table 2, if the photocurability of the photocurable coating composition is evaluated to be poor (x), the refractive index, transmittance, and yellowing test of the subsequent photocurable coating film are performed. Not done. Experimental Example 8 did not perform the subsequent penetration and yellowing test on the photo-curing coating film.

The following abbreviations in Tables 1 and 2 are described below:

As is apparent from the above Table 1, the photocurable coating compositions of Experimental Examples 1 to 7 all have good photocurability, and the obtained photohardenable coating film has refractive index, transmittance, and yellowing. Tests have performed well. The photocurable coating composition of Experimental Example 8 had good photocurability, and the obtained photocurable coating film exhibited good performance in refractive index test. On the other hand, as seen from the above Table 2, the photocurable coating compositions of Comparative Example 2, Comparative Example 4, and Comparative Example 8 did not have good photocurability, and Comparative Example 1, Comparative Example 3, and Comparative Example 5 were compared. Although the photocurable coating compositions of Example 7 all had good photocurability, the obtained photohardenable coating films could not perform well in refractive index, transmittance, and yellowing test at the same time.

In summary, the photocurable coating composition of the present invention comprises at least a metal alkoxide represented by the formula (I), a metal alkoxide represented by the formula (II), and a formula (III) a photocurable polymer obtained by reacting a metal alkoxide shown, wherein the metal alkoxide represented by the formula (I), the metal alkoxide represented by the formula (II), and the formula (III) The content of the metal alkoxide represented by the formula (I) is from 25 parts by weight to 50 parts by weight based on 100 parts by weight of the total amount of the metal alkoxide, and the content of the metal alkoxide represented by the formula (II) is 5. The metal alkoxide represented by the formula (III) is contained in an amount of from 45 parts by weight to 70 parts by weight per part by weight to 20 parts by weight. By including the above photocurable polymer, the photocurable coating composition of the present invention has good photocurability, and can be used to obtain a photohardenable coating which exhibits good performance in refractive index, transmittance, and yellowing test. Cloth film. Another photocurable coating composition according to the present invention, which comprises a photohardening reaction consisting essentially of a metal alkoxide represented by the formula (II) and a metal alkoxide represented by the formula (III) a polymer, wherein the metal alkoxide represented by the formula (II) and the formula (III) The metal alkoxide represented by the formula (III) is contained in an amount of from 55 parts by weight to 70 parts by weight based on 100 parts by total of the metal alkoxide. By including the photocurable polymer described above, the photocurable coating composition of the present invention has good photocurability, and a photocurable coating film which is excellent in refractive index test can be obtained. As a result, the touch panel using the photo-curing coating film of the present invention can have good visibility and display quality.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and any one of ordinary skill in the art can make some changes and refinements without departing from the spirit and scope of the present invention. The scope of the invention is defined by the scope of the appended claims.

Claims (12)

A photocurable coating composition comprising: a photocurable polymer comprising at least a metal alkoxide represented by the formula (I), a metal alkoxide represented by the formula (II), and a formula (III) The metal alkoxide is obtained by hydrolysis and condensation reaction: R ^a ₁ Si(OR ^b ) ₃ formula (I); R ^c ₁ Si(OR ^d ) ₃ formula (II); Ti(OR ^e ) ₄ formula (III) Wherein R ^a represents an aromatic group having 6 to 15 carbon atoms, R ^b represents an alkyl group having 1 to 5 carbon atoms, R ^c represents an alkenyl group having 2 to 10 carbon atoms which does not contain an aromatic group, and R ^d represents a carbon number of 1 to 5; An alkyl group of 5, R ^e represents an alkyl group having 1 to 5 carbon atoms, and a metal alkoxide represented by the above formula (I), a metal alkoxide represented by the formula (II), and the formula The total amount of the metal alkoxide shown in (III) is 100 parts by weight, and the content of the metal alkoxide represented by the formula (I) is from 25 parts by weight to 50 parts by weight, the formula (II) The metal alkoxide is present in an amount of from 5 parts by weight to 20 parts by weight, and the metal alkoxide represented by the formula (III) is contained in an amount of from 45 parts by weight to 70 parts by weight. The photocurable coating composition according to claim 1, wherein the metal alkoxide represented by the formula (I), the metal alkoxide represented by the formula (II), and the The total amount of the metal alkoxide represented by the formula (III) is 100 parts by weight, and the metal alkoxide represented by the formula (I) is contained in an amount of from 25 parts by weight to 45 parts by weight. The photocurable coating composition according to claim 1, wherein the metal alkoxide represented by the formula (I) and the metal alkoxide represented by the formula (II) And the total amount of the metal alkoxide represented by the formula (III) is 100 parts by weight, and the metal alkoxide represented by the formula (I) is contained in an amount of 30 parts by weight to 40 parts by weight. The photocurable coating composition according to claim 1, further comprising a solvent. A photo-curable coating film obtained by the photocurable coating composition according to any one of claims 1 to 4. The photo-curing coating film according to claim 5, which has a film thickness of 80 nm to 120 nm and a refractive index of 1.60 to 1.70. The photo-curing coating film according to claim 5, wherein the film thickness of the photo-curing coating film is from 80 nm to 120 nm, and in the range of from 380 nm to 450 nm, the photo-curing coating film The penetration rate is greater than 95%. A photocurable coating composition comprising: a photocurable polymer substantially composed of a metal alkoxide represented by the formula (II) and a metal alkoxide represented by the formula (III) by hydrolysis and condensation reaction Obtained: R ^c ₁ Si(OR ^d ) ₃ Formula (II); Ti(OR ^e ) ₄ Formula (III); wherein R ^c represents an alkenyl group having 2 to 10 carbon atoms, and R ^d represents an alkane having 1 to 5 carbon atoms And R ^e represents an alkyl group having 1 to 5 carbon atoms, and the total amount of the metal alkoxide represented by the formula (II) and the metal alkoxide represented by the formula (III) is 100 parts by weight. The content of the metal alkoxide represented by the formula (III) is from 55 parts by weight to 70 parts by weight. The photocurable coating composition according to Item 8 of the patent application, further comprising a solvent. A photo-curable coating film obtained by the photocurable coating composition according to any one of claims 8 to 9. The photocurable coating film according to claim 10, which has a film thickness of from 80 nm to 120 nm and a refractive index of from 1.60 to 1.70. A touch panel comprising the photo-curing coating film according to any one of claims 5 to 7 or 10 to 11.