KR20180036762A - Preferred glass substrates for cover glasses of mobile display devices - Google Patents

Abstract

There is provided a glass substrate having high scratch resistance, slipperiness, good visibility, and low reflectance, particularly as a cover glass of a mobile display device or the like. A polysiloxane obtained by polycondensation of an alkoxysilane represented by the following formula (1) and, optionally, an alkoxysilane represented by the following formula (2), between the fluorine coating layer on the front surface side and the DLC layer on the substrate side The glass substrate having an intermediate layer formed thereon.
R ¹ {Si (OR ² ) ₃ } _P (1)
(R ¹ is a hydrocarbon group of 1 to 12 carbon atoms substituted with a ureide group, R ² is an alkyl group of 1 to 5 carbon atoms, and p is an integer of 1 or 2)
(R ³ ) _n Si (OR ⁴ ) _4-n (2)
(R ³ represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms which may be substituted with a hetero atom, a halogen atom, a vinyl group, an amino group, a glycidoxy group, a mercapto group, a methacryloxy group, an isocyanate group, R ⁴ is an alkyl group having 1 to 5 carbon atoms, and n is an integer of 0 to 3)

Description

Preferred glass substrates for cover glasses of mobile display devices

The present invention relates to a glass substrate preferably used as a glass substrate having high scratch resistance, slipperiness, good visibility, and low reflectance, particularly, a cover glass of a mobile display device or the like.

Recently, a cover glass for protecting the surface of a display device is widely used in a liquid crystal display device such as a mobile device or a touch panel. In addition, a glass plate having excellent scratch resistance and good visibility is also used for a protective glass such as a finder of a watch or a camera (see Patent Document 1 and Patent Document 2).

In the cover glass of such a display element, a high hardness and a high scratch-off property are demanded in order to prevent cracks and to prevent scratches from occurring more easily. However, when a diamond-like carbon (DLC) layer or the like is formed on a glass substrate in order to increase hardness and scratch resistance, slipperiness of the cover glass is usually given, The adhesion to the fluorine-containing coating layer becomes poor, and the slipping property is remarkably lowered during use (see Patent Document 3).

Japanese Laid-Open Patent Publication No. 2009-186234 Japanese Laid-Open Patent Publication No. 2009-186236 Japanese Patent Application Laid-Open No. 2010-228307

It is an object of the present invention to provide a glass substrate which is preferably used as a glass substrate having excellent scratch resistance, corrosion resistance and good visibility, particularly as a cover glass for a display device such as a mobile device or a touch panel.

The inventors of the present invention have made extensive studies in view of the above circumstances, and as a result, they have completed the present invention described below.

1. A glass substrate having a fluorine coating layer on the front surface side and a diamond-like carbon (DLC) layer on the substrate side, wherein the glass substrate comprises an alkoxysilane represented by the following formula (1) and an alkoxy silane containing an alkoxysilane represented by the following formula And an intermediate layer made of a film containing a polysiloxane obtained by polycondensing a silane between the fluorocarbon coating layer and the DLC layer.

R ¹ {Si (OR ² ) ₃ } _P (1)

(R ¹ is a hydrocarbon group of 1 to 12 carbon atoms substituted with a ureide group, R ² is an alkyl group of 1 to 5 carbon atoms, and p is an integer of 1 or 2)

(R ³ ) _n Si (OR ⁴ ) _4-n (2)

(R ³ represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms which may be substituted with a hetero atom, a halogen atom, a vinyl group, an amino group, a glycidoxy group, a mercapto group, a methacryloxy group, an isocyanate group, R ⁴ is an alkyl group of 1 to 5 carbon atoms, and n is an integer of 0 to 3)

Wherein the alkoxysilane represented by the formula (1) is at least one selected from the group consisting of? -Ureidopropyltriethoxysilane,? -Ureidopropyltrimethoxysilane and? -Ureidopropyltripropoxysilane The glass substrate according to 1 above.

3. The glass substrate according to 1 or 2 above, wherein the alkoxysilane represented by the formula (2) is tetraalkoxysilane in which n is 0 in the formula (2).

4. The glass substrate according to any one of 1 to 3 above, wherein the alkoxysilane represented by the formula (1) is contained in an amount of 0.5% or more based on the total alkoxysilane.

5. The alkoxysilane represented by the above formula (1), wherein the alkoxysilane represented by the formula (1) is contained in an amount of 0.5 to 60 mol% in the total alkoxysilane and the alkoxysilane represented by the formula To (4).

6. The glass substrate according to any one of 1 to 5 above, wherein the fluorine-containing coating layer is formed of an axial polymer of a perfluoroalkyl or perfluoropolyether silane compound.

7. The glass substrate according to any one of 1 to 6 above, wherein the thickness of the fluorine coating layer is 1 to 30 nm, the thickness of the diamond like carbon layer is 50 to 150 nm, and the thickness of the intermediate layer is 10 to 500 nm.

8. A display device comprising the glass substrate according to any one of 1 to 7 above.

According to the present invention, by having an intermediate layer of a specific polysiloxane in addition to a fluorine coating layer on the surface and a DLC layer on the substrate side with high scratch resistance and slippery property, the transmittance can be improved unexpectedly , And the reflectance is lowered, thereby providing a glass substrate having excellent visibility.

In the glass substrate of the present invention, since the above-mentioned specific polysiloxane intermediate layer can be cured at a low temperature of 300 ° C or less, the production efficiency is good, and the fluorine coating layer and / Since it has high adhesion to the DLC layer, it does not affect the properties of electronic devices and the like, and is particularly preferably used as a cover glass for liquid crystal display devices.

1 is a schematic sectional view showing an example of a glass substrate according to an embodiment of the present invention.

[Glass Substrate]

As the glass substrate of the present invention, a glass plate made of alkali glass, quartz glass, sapphire glass, alumina silicon glass, or the like can be widely used. Thickness is not particularly limited, but is usually 0.1 to 2.0 mm, more preferably 0.2 to 1.3 mm. In order to increase the strength, the glass plate may be chemically reinforced or reinforced by wind. The glass substrate of the present invention has a DLC layer on the substrate side and a fluorine coating layer on the surface side.

[DLC layer]

The DLC layer on the substrate side of the glass substrate is formed in order to impart high scratch resistance and corrosion resistance. The DLC layer in the present invention can be easily obtained by using a hydrocarbon gas such as acetylene or methane as a raw material by a plasma CVD method, a sputtering method, an ionization deposition method, and the like, preferably by a sputtering method. The raw material may contain hydrogen.

The thickness of the DLC layer in the present invention is preferably 50 to 150 nm, and more preferably 70 to 130 nm. The refractive index is preferably 1.7 or less, and more preferably 1.5 or less, in order to achieve low reflection. The DLC layer may be porous and the volume ratio of vacancies is preferably 40 to 70%, more preferably 45 to 65%.

[Fluorine Coating Layer]

The fluorine coating layer on the surface side of the glass substrate is formed in order to improve slipperiness and to improve ease of operation and prevention of fingerprint adhesion. A glass substrate having a fluorine coating layer on its surface is already known from, for example, International Publication Nos. WO2013 / 115191 and 2014-218639, and the fluorine coating layer may be those already known in the present invention.

Fluorine coating layer in the present invention, for _{^{example, R f -Q 1 -SiX 1 3}} (R f is a perfluoroalkyl of 1 to 6 carbon atoms, Q ¹ is a fluorine atom the carbon number is 1 to 10 (X ¹ is a hydrolyzable group such as a halogen atom or an alkoxy group), or a silane compound having a perfluoroalkyl group such as CF ₃ CF ₂ CF ₂ O (CF ₂ CF ₂ CF ₂ O) ₂₀ CF ₂ CF ₂ CH ₂ OCH ₂ CH ₂ CH ₂ SiCl ₃ , CF ₃ CF ₂ CF ₂ O (CF ₂ CF ₂ CF ₂ O) ₂₀ CF ₂ CF ₂ CH ₂ OCH ₂ CH ₂ CH ₂ Si ₂ CH = CH ₂ ) ₃ , and the like, as well as a fluorinated polymer such as a condensate of a perfluoro (poly) ether group-containing silane compound. A fluorine coating layer is formed by applying a solution prepared by dispersing these fluorine-containing polymerizers in a medium onto a DLC layer of a glass substrate, and drying and heating.

The thickness of the fluorine coating layer is preferably 1 to 30 nm, more preferably 1 to 15 nm in terms of optical performance, surface slipperiness, friction durability and antifouling property.

[Middle layer]

The intermediate layer in the present invention is used between the fluorine coating layer and the DLC layer and is characterized by containing a polysiloxane having a ureide group as described below. This makes it possible to form a film having sufficient hardness and adhesion even at a low temperature of 100 to 300 캜.

That is, the intermediate layer in the present invention contains a polysiloxane obtained by polycondensation of an alkoxysilane represented by the following formula (1) and, if necessary, an alkoxysilane containing an alkoxysilane represented by the following formula (2).

R ¹ {Si (OR ² ) ₃ } _P (1)

In the formula (1), R ¹ is a hydrocarbon group having 1 to 12 carbon atoms and having a ureide group. Among them, R ¹ is preferably a hydrocarbon group of 1 to 7, more preferably 1 to 5, and any hydrogen atom thereof, preferably 3 to 15 hydrogen atoms, particularly preferably 3 to 11 hydrogen atoms Is a group substituted with a ureide group. The hydrocarbon group is preferably an alkyl group.

R ² is an alkyl group having 1 to 5 carbon atoms, preferably 1 to 3 carbon atoms, more preferably a methyl group or an ethyl group. p represents an integer of 1 or 2;

The alkoxysilane represented by the formula (1) is an alkoxysilane represented by the formula (1-1) when p is 1.

R ¹ Si (OR ² ) ₃ (1-1)

The alkoxysilane represented by the formula (1) is an alkoxysilane represented by the formula (1-2) when p is 2.

(R ² O) ₃ Si-R ¹ -Si (OR ² ) ₃ (1-2)

Specific examples of the alkoxysilane represented by the formula (1-1) include, but are not limited to, the following. (R) -N-1-phenylethyl-N ' -triethoxysilane, [gamma] -ureidopropyltrimethoxysilane, [gamma] -ureidopropyltripropoxysilane, (R) -N-1-phenylethyl-N'-trimethoxysilylpropylurea, and the like. Among them, γ-ureidopropyltriethoxysilane or γ-ureidopropyltrimethoxysilane is particularly preferable because it is readily available as a commercial product.

Specific examples of the alkoxysilane represented by the formula (1-2) include, but are not limited to, the following. For example, there may be mentioned bis [3- (triethoxysilyl) propyl] urea, bis [3- (triethoxysilyl) ethyl] urea, bis [3- (trimethoxysilyl) (Tripropoxysilyl) propyl] urea. Among them, bis [3- (triethoxysilyl) propyl] urea is particularly preferable because it is commercially available as a commercially available product.

The alkoxysilane represented by the formula (1) is preferably 0.5 mol% or more, more preferably 1.0 mol% or more, and further preferably 2.0 mol% or more in the total alkoxysilane used for obtaining the intermediate layer. The alkoxysilane represented by the formula (1) may be 100 mol% of the total alkoxysilane used for obtaining the intermediate layer.

The alkoxysilane for obtaining the intermediate layer is preferably an alkoxysilane represented by the following formula (2) together with the alkoxysilane represented by the above formula (1).

(R ³ ) _n Si (OR ⁴ ) _4-n (2)

In formula (2), R ³ represents a hydrogen atom or a carbon atom which may be substituted by a hetero atom, a halogen atom, a vinyl group, an amino group, a glycidoxy group, a mercapto group, a methacryloxy group, an isocyanate group, And is a hydrocarbon group having 1 to 6 atoms. R ⁴ is an alkyl group of 1 to 5 carbon atoms, preferably 1 to 3 carbon atoms. n represents an integer of 0 to 3, preferably 0 to 2;

Examples of R ^{3 in} the formula (2) include aliphatic hydrocarbons; A cyclic structure such as an aliphatic ring, an aromatic ring or a heterocyclic ring; Unsaturated bonds; A hetero atom such as an oxygen atom, a nitrogen atom or a sulfur atom, or an organic group having 1 to 6 carbon atoms which may have a branched structure. Further, R ³ may be substituted with a halogen atom, a vinyl group, an amino group, a glycidoxy group, a mercapto group, a methacryloxy group, an isocyanate group, an acryloxy group and the like. R ⁴ has the same meaning as R ² described above, and the preferred range is also the same.

Specific examples of the alkoxysilane represented by the formula (2) include, but are not limited to, Specifically, specific examples of the alkoxysilane in which R ³ is a hydrogen atom in the alkoxysilane represented by the formula (2) include trimethoxysilane, triethoxysilane, tripropoxysilane, tributoxysilane, and the like. .

Specific examples of the alkoxysilane represented by the other formula (2) include methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, Aminopropyltriethoxysilane, N-2 (aminoethyl) 3-aminopropyltriethoxysilane, N-2 (aminoethyl) aminopropyltrimethoxysilane, ), 3-aminopropyltrimethoxysilane, 3- (2-aminoethylaminopropyl) trimethoxysilane, 3- (2-aminoethylaminopropyl) triethoxysilane, 2-aminoethylaminomethyltrimethoxysilane , 2- (2-aminoethylthioethyl) triethoxysilane, 3-mercaptopropyltriethoxysilane, mercaptomethyltrimethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, allyltriethoxy Silane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltri Acryloxypropyltrimethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-acryloxypropyltriethoxysilane, 3-isocyanatepropyltriethoxysilane, trifluoropropyltrimethoxysilane, chloropropyltriethoxysilane, bromo Propyltrimethoxysilane, propyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, dimethyldiethoxysilane, dimethyldimethoxysilane, diethyldiethoxysilane, diethyldimethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, 3-aminopropylmethyldiethoxysilane, 3-aminopropyldimethylethoxysilane, trimethylethoxysilane, trimethylmethoxysilane, and the like.

In the alkoxysilane represented by the formula (2), the alkoxysilane wherein n is 0 is tetraalkoxysilane. Since tetraalkoxysilane is easily condensed with an alkoxysilane represented by the formula (1), it is preferable to obtain the polysiloxane of the present invention. As the alkoxysilane in which n is 0 in the formula (2), tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane or tetrabutoxysilane is more preferable, and tetramethoxysilane or tetraethoxysilane Particularly preferred.

When the alkoxysilane represented by the formula (2) is used, the amount of the alkoxysilane to be used is preferably from 40 to 99.5 mol%, more preferably from 50 to 99.5 mol% in the total alkoxysilane used for obtaining the intermediate layer And preferably 60 to 99.5 mol%. In this case, the alkoxysilane represented by the formula (1) is preferably 60 mol% or less, more preferably 50 mol% or less, further preferably 40 mol% or less, of the total alkoxysilane used for obtaining the intermediate layer .

The polysiloxane forming the intermediate layer in the present invention is obtained by preferably polycondensing an alkoxysilane represented by the formula (1) and an alkoxysilane containing an alkoxysilane represented by the formula (2), if necessary. The intermediate layer may contain a plurality of alkoxysilanes represented by formula (1) and alkoxysilanes represented by formula (2), respectively, as long as they do not impair their properties.

Examples of the polycondensation method in the present invention include a method of hydrolyzing and condensing the alkoxysilane in an organic solvent such as an alcohol or a glycol. At this time, the hydrolysis-condensation reaction may be partial hydrolysis or complete hydrolysis. In the case of complete hydrolysis, it is theoretically possible to add water at a molar ratio of 0.5 times the total alkoxide group in the alkoxysilane, and it is usually preferable to add an excess amount of water in excess of 0.5 times mol. The amount of water can be appropriately selected according to the desired amount, but is preferably 0.5 to 2.5 times the total moles of alkoxy groups in the alkoxysilane.

In the present invention, an acid such as hydrochloric acid, sulfuric acid, nitric acid, acetic acid, formic acid, oxalic acid, maleic acid, fumaric acid, etc .; Alkali such as ammonia, methylamine, ethylamine, ethanolamine, triethylamine and the like; It is preferable to use a catalyst such as a metal salt of hydrochloric acid, sulfuric acid or nitric acid. It is also preferable to further accelerate the hydrolysis / condensation reaction by heating the solution in which the alkoxysilane is dissolved. At that time, the heating temperature and the heating time can be appropriately selected according to the desired one. For example, heating and stirring at 50 ° C to reflux for 1 to 24 hours.

As another method, a method of heating an alkoxysilane, an organic solvent, and a mixture of organic acids such as formic acid, oxalic acid, maleic acid, and fumaric acid to polycondense. For example, a method in which a mixture of alkoxysilane, a solvent and oxalic acid is heated and polycondensed. Specifically, oxalic acid is added to the alcohol in advance to prepare an alcohol solution of oxalic acid, and then the solution is heated to mix the alkoxysilane. At this time, the amount of oxalic acid to be used is preferably 0.2 to 2 mol per 1 mol of the total alkoxy group of the alkoxysilane. The heating in this method can be carried out at a liquid temperature of 50 to 180 ° C. Preferably, the solution is heated for several tens of minutes to several tens of hours under reflux so as not to evaporate or volatilize the solution.

When a plurality of alkoxysilanes are used in obtaining the polysiloxane, they may be mixed as a mixture of alkoxysilanes in advance, or a plurality of alkoxysilanes may be sequentially mixed.

The solvent used for polycondensing the alkoxysilane (hereinafter also referred to as a polymerization solvent) is not particularly limited as long as it dissolves the alkoxysilane. In addition, even when the alkoxysilane is not dissolved, it may be any one that dissolves along with the progress of the polycondensation reaction of the alkoxysilane. Generally, an organic solvent having good compatibility with alcohols, glycols, glycol ethers, or alcohols is used because alcohol is produced by the polycondensation reaction of alkoxysilane.

Specific examples of the organic solvent in the condensation reaction include alcohols such as methanol, ethanol, propanol, butanol, and diacetone alcohol: ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, hexylene glycol, Butanediol, 1,3-butanediol, 2,3-butanediol, 1,2-pentanediol, 1,3-pentanediol, 1,4-pentanediol, Glycols such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monoethyl ether, Ethylene glycol monobutyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dipropyl ether, ethylene glycol dibutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, Diethylene glycol mono Diethylene glycol diethyl ether, diethylene glycol dipropyl ether, diethylene glycol dibutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, Glycol ethers such as monobutyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol dipropyl ether and propylene glycol dibutyl ether, and N-methyl-2-pyrrolidone, N, N, N-dimethylacetamide, gamma -butyrolactone, dimethylsulfoxide, tetramethylurea, hexamethylphosphoric triamide, and m-cresol. A plurality of the above organic solvents may be mixed and used.

The polymerization solution of polysiloxane (hereinafter also referred to as a polymerization solution) obtained by the above-mentioned method is a solution containing 20 mass% of the total alkoxysilane injected as a raw material in terms of a concentration of silicon atoms converted to SiO ₂ (hereinafter referred to as SiO ₂ concentration) Or less. By selecting an arbitrary concentration in this concentration range, it is possible to obtain a homogeneous solution by suppressing gel formation.

In the present invention, the polymerized solution of the polysiloxane obtained as described above may be used to form the intermediate layer as it is. If necessary, the above polymerization solution may be concentrated or added with a solvent or diluted or replaced with another solvent.

At this time, the solvent to be used (hereinafter also referred to as an addition solvent) may be the same as the polymerization solvent or may be another solvent. The addition solvent is not particularly limited as long as the polysiloxane is dissolved uniformly, and it may be a kind, a plurality of kinds, or may be arbitrarily selected and used.

Specific examples of such an addition solvent include ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone, as well as solvents exemplified by the above-mentioned polymerization solvents; And esters such as methyl acetate, ethyl acetate and ethyl lactate. The viscosity adjusted by these solvents can be applied to the substrate by spin coating, flexo printing, ink jet, slit coating, etc. to improve the coating property when the intermediate layer is formed.

In the present invention, the coating liquid for forming the intermediate layer contains other components other than the above polysiloxane such as inorganic fine particles, metal oxalate oligomer, metal oxalate polymer, leveling agent, and further, surfactant .

As the inorganic fine particles, fine particles such as silica fine particles, alumina fine particles, titania fine particles, or magnesium fluoride fine particles are preferable, and in particular, they are preferably in a colloid solution state. By including the inorganic fine particles in the coating liquid at the time of forming the intermediate layer, adjustment of the surface shape and refractive index of the formed cured coating and other functions can be imparted. The inorganic fine particles preferably have an average particle diameter (D50) of 0.001 to 0.2 mu m, more preferably 0.001 to 0.1 mu m. When the average particle diameter exceeds 0.2 탆, the transparency of the intermediate layer to be formed may be lowered.

Examples of the dispersion medium of the inorganic fine particles include water and an organic solvent. As the colloidal solution, the pH or pKa is preferably 1 to 10, more preferably 2 to 7, from the viewpoint of the stability of the polysiloxane liquid.

Examples of the organic solvent for use in the dispersion medium of the colloid solution include alcohols such as methanol, propanol, butanol, ethylene glycol, propylene glycol, butanediol, pentanediol, hexyleneglycol, diethylene glycol, dipropylene glycol and ethylene glycol monopropyl ether ; Ketones such as methyl ethyl ketone and methyl isobutyl ketone; Aromatic hydrocarbons such as toluene and xylene; Amides such as dimethylformamide, dimethylacetamide and N-methylpyrrolidone; Esters such as ethyl acetate, butyl acetate and? -Butyrolactone; And ethers such as tetrahydrofuran and 1,4-dioxane. Of these, alcohols and ketones are preferred. The organic solvent may be used alone or in combination of two or more.

As the metal oxyne oligomer and the metal oxide polymer, a single or complex oxide precursor such as silicon, titanium, aluminum, tantalum, antimony, bismuth, tin, indium, The methacrylic acid oligomer and the methacrylic acid polymer may be obtained by hydrolysis or the like from monomers such as metal alkoxide, nitrate, hydrochloride, and carboxylate.

The metal oxane oligomer and the metal oxane polymer may be commercially available products. Examples thereof include methyl silicate 51, methyl silicate 53A, ethyl silicate 40, ethyl silicate 48, EMS-485, SS-101 and the like manufactured by Colcoat; And titanium oxyne oligomers such as titanium-n-butoxide tetramer manufactured by Kanto Chemical. These may be used alone or in combination of two or more.

As the leveling agent and the surfactant, known ones, especially commercial ones, can be used. The method of mixing the above other components with the polysiloxane may be carried out simultaneously with or after the polysiloxane, and is not particularly limited.

An intermediate layer can be obtained by applying the polysiloxane solution of the present invention onto a DLC layer of a glass substrate and thermally curing it. The application of the polysiloxane solution can be carried out by known methods or well-known methods. For example, a dip coating method, a float coating method, a spray coating method, a bar coating method, a gravure coating method, a roll coating method, a blade coating method, an air knife coating method, a flexo printing method, an ink jet method, have. Among them, a good coating film can be formed by the flexo printing method, the slit coat method, the ink jet method, the spray coat method and the gravure coat method.

The polysiloxane solution is preferably filtered using a filter or the like before application. The formed coating film is preferably thermally cured at room temperature to 120 ° C, more preferably at 50 to 100 ° C, preferably at 100 to 600 ° C, more preferably at 150 ° C or more. The time required for drying is preferably 1 minute to 30 minutes, more preferably 1 minute to 10 minutes. The heat curing time is preferably 10 minutes to 24 hours, more preferably 30 minutes to 24 hours.

The intermediate layer used in the glass substrate of the present invention can obtain a cured film having sufficient hardness even at a curing temperature exceeding 180 캜. The thickness of the intermediate layer in the present invention is preferably 10 to 500 nm, and more preferably 30 to 300 nm.

It is also effective to irradiate an energy ray (ultraviolet ray or the like) using a mercury lamp, a metal halide lamp, a xenon lamp, an excimer lamp or the like prior to thermosetting. By irradiating the dried coating film with an energy ray, the curing temperature can be further lowered or the hardness of the coating film can be increased. The irradiation amount of the energy ray can be appropriately selected in accordance with the necessity, but usually it is preferably several hundreds to several thousands mJ / cm2.

In the present invention, a fluorine coating layer is formed on the surface of the intermediate layer obtained as described above. Such a fluorine coating layer is already known as described above, and is formed by a known method.

1 is a schematic sectional view showing an example of a glass substrate of an embodiment of the present invention. The glass 1 comprises a fluorine coating layer 2, an intermediate layer 3, a DLC layer 4, and a glass substrate 5. The intermediate layer 3 is an intermediate layer formed on the DLC layer. The fluorine-containing coating layer is formed by coating the fluorine-containing polymer-containing liquid described above and firing it. A glass substrate of the present invention is obtained by using a glass substrate having a DLC layer, forming an intermediate layer on the DLC layer, and then forming a fluorine coating layer on the intermediate layer.

Example

EXAMPLES Hereinafter, the present invention will be described in detail with reference to Examples of the present invention, but the present invention is not construed as being limited to the following Examples. The meanings of the abbreviations in the following and measurement methods are as follows.

TEOS: tetraethoxysilane

UPS: 3-ureidopropyltriethoxysilane

MeOH: methanol

EtOH: ethanol

IPA: Isopropyl alcohol

PGME: Propylene glycol monomethyl ether

HG: hexylene glycol

BCS: ethylene glycol monobutyl ether

AF: Fluomat P-5425, manufactured by FT-Net

[Method for measuring residual alkoxysilane monomer]

The residual alkoxysilane monomer in the polysiloxane solution was measured by gas chromatography (hereinafter referred to as GC). GC measurement was carried out using Shimadzu GC-14B (Shimadzu Corporation) under the following conditions.

Column: capillary column CBP1-W25-100 (length 25 mm, diameter 0.53 mm, thickness 1 占 퐉)

Column temperature: The temperature was raised from the initiation temperature of 50 占 폚 to 15 占 폚 / min to give an ultimate temperature of 290 占 폚 (retention time of 3 minutes).

Sample injection amount: 1 占,, injection temperature: 240 占 폚, detector temperature: 290 占 폚, carrier gas: nitrogen (flow rate: 30 ml / min)

[Steel Wool Scratch Resistance]

Speed: 25 round trips / minute, distance: 6 cm, area: 2 cm (length) using a steel wool scuffing tester (manufactured by Taiei Jungwon) × 2 cm, load: 1 kg, and then the water contact angle was measured.

[Water contact angle]

Using a contact angle meter DM-701 (manufactured by Kyowa Interface Chemicals Co., Ltd.), 3 탆 (liters) of water was dropped on the steel wool scratch test point on the substrate, and the water contact angle was measured.

[Average transmittance]

The glass substrates of samples 1 to 3 obtained in the examples and comparative examples were measured for transmittance spectra at visible light wavelengths (380 to 780 nm) using an ultraviolet visible spectrophotometer UV-3600 (product name of Shimadzu Corporation) And the value obtained by multiplying the weighted average by the weighted coefficient obtained from the wavelength distribution of the non-viscous sensitivity was taken as an average transmittance. The results of measurement according to JIS R3106 (1998) are shown in Table 1.

[Average reflectance]

The glass substrates of the samples 1 to 3 obtained in the examples and comparative examples were measured using an ultraviolet visible spectrophotometer UV-3600 (manufactured by Shimadzu Corporation), an absolute specular reflection measuring apparatus ASR3145 and a multipurpose large sample chamber MPC-3100 ? Reflectance The reflectance spectrum at the wavelength (380 to 780 nm) was multiplied by a weighted coefficient obtained from the wavelength distribution of the main spectrum and the nonvisible sensitivity, and the value obtained by weighted average was taken as the average reflectance. The results of measurement according to JIS R3106 (1998) are shown in Table 1. The results are shown in Table 1.

[Production Example 1]

MeOH (27.25 g) as a solvent and TEOS (32.98 g) as an alkoxysilane were added to a four-neck reaction flask equipped with a reflux tube and stirred.

Then, MeOH (11.23 g) as a solvent, a mixture of 6% nitric acid solution (8.75 g) as an acid and water (15.0 g) was added dropwise and stirred for 30 minutes. After stirring and refluxing for 2 hours, 92% UPS (2.39 g) and MeOH (2.39 g) were added as alkoxysilane, refluxed for 30 minutes and then cooled to room temperature. After cooling, MeOH (70.67 g) was added as a solvent to prepare a solution (A) of polysiloxane.

As a result of measuring the solution of the polysiloxane by GC, no alkoxysilane monomer was detected.

[Comparative Production Example 1]

MeOH (27.92 g) as a solvent and TEOS (34.72 g) as an alkoxysilane were added to a four-neck reaction flask equipped with a reflux tube and stirred.

Then, a mixture of MeOH (13.96 g) as a solvent, a 6% nitric acid solution (8.75 g) as an acid, and water (14.65 g) was added dropwise and stirred for 30 minutes. After stirring, the mixture was refluxed for 2 hours and 30 minutes, and then cooled to room temperature. After cooling, MeOH (70.67 g) was added as a solvent to prepare a solution (B) of polysiloxane.

As a result of measuring the solution of the polysiloxane by GC, no alkoxysilane monomer was detected.

[Example 1]

The polysiloxane solution (A) (50 g) obtained in Preparation Example 1 was diluted with PGME (30 g), HG (10 g), BCS (5 g) and PB (5 g) A1).

On the DLC layer of a glass substrate (thickness: 0.7 mm) on which a DLC layer with a thickness of 100 nm was formed by sputtering, the coating liquid for film formation (A1) was applied by a spin coater to form a coating film. Subsequently, the glass plate on which the coated film was formed was dried on a hot plate at 80 ° C for 3 minutes, and then cured in a clean oven at 300 ° C for 30 minutes to obtain a glass substrate having a coating film (intermediate layer) having a thickness of 100 nm.

On the intermediate layer of this glass substrate, AF was applied by a spin coater to form a coating film of a fluorine coating layer having a thickness of about 10 nm so that the contact angle was about 113 degrees. Subsequently, the substrate was dried on a hot plate at 80 ° C for 3 minutes, and then cured in a clean oven at 170 ° C for 20 minutes to obtain a glass substrate of Sample 1 (Example 1).

[Comparative Example 1]

Except for using the polysiloxane solution (A) obtained in Preparation Example 1 and forming the coating film of the fluorine-containing coating layer directly on the DLC layer of the glass substrate without applying the intermediate layer, , And a glass substrate of Sample 2 (Comparative Example 1) was obtained in the same manner as in Example 1.

[Comparative Example 2]

Sample 3 (Comparative Example 2) was obtained in the same manner as in Example 1, except that the polysiloxane solution (B) obtained in Comparative Preparation Example 1 was used instead of the polysiloxane solution (A) obtained in Production Example 1, ) Was obtained.

The water contact angle, average transmittance, and average reflectance after the steel wool anti-scratch test were measured for each of Sample 1 (Example 1), Sample 2 (Comparative Example 1) and Sample 3 (Comparative Example 2) , And the results are shown in Tables 1 and 2. In the table, "-" means unmeasured.

As shown in Table 1 and Table 2, in the examples, even when the steel wool scratch resistance test was repeated 9000 times, the water contact angle was 90 ° or more and the transmittance was 94% or more. .

On the other hand, in Comparative Examples 1 and 2, although the steel wool scratch resistance test was 5000 round trips or less and all had a low water contact angle of 90 ° or less, scratch resistance was low and the average transmittance was 94% , And the average reflectance was 6% or more, which was higher than that of the Examples.

Industrial availability

The glass substrate of the present invention is widely used as a cover glass for display devices such as mobile devices and touch panels.

The entire contents of the specification, claims, drawings and summary of Japanese Patent Application No. 2015-152008 filed on July 31, 2015 are hereby incorporated herein by reference as the disclosure of the specification of the present invention.

1: Cover glass
2: Fluorine coating layer
3: Middle layer
4: DLC layer
5: glass substrate

Claims (8)

A glass substrate having a fluorine coating layer on the surface side and a diamond-like carbon (DLC) layer on the substrate side, an alkoxysilane represented by the following formula (1) and an alkoxy silane containing an alkoxysilane represented by the following formula (2) And an intermediate layer containing a polysiloxane obtained by polycondensation of silane between the fluorine coating layer and the DLC layer.
R ¹ {Si (OR ² ) ₃ } _P (1)
(R ¹ is a hydrocarbon group of 1 to 12 carbon atoms substituted with a ureide group, R ² is an alkyl group of 1 to 5 carbon atoms, and p is an integer of 1 or 2)
(R ³ ) _n Si (OR ⁴ ) _4-n (2)
(R ³ represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms which may be substituted with a hetero atom, a halogen atom, a vinyl group, an amino group, a glycidoxy group, a mercapto group, a methacryloxy group, an isocyanate group, R ⁴ is an alkyl group of 1 to 5 carbon atoms, and n is an integer of 0 to 3) The method according to claim 1,
Wherein the alkoxysilane represented by the formula (1) is at least one selected from the group consisting of? -Ureidopropyltriethoxysilane,? -Ureidopropyltrimethoxysilane and? -Ureidopropyltripropoxysilane, Board. 3. The method according to claim 1 or 2,
Wherein the alkoxysilane represented by the formula (2) is tetraalkoxysilane in which n is 0 in the formula (2). 4. The method according to any one of claims 1 to 3,
A glass substrate wherein the alkoxysilane represented by the formula (1) is contained in an amount of 0.5% or more in the total alkoxysilane. 5. The method according to any one of claims 1 to 4,
A glass substrate wherein the alkoxysilane represented by the formula (1) is contained in an amount of 0.5 to 60 mol% in the total alkoxysilane and the alkoxysilane represented by the formula (2) is contained in the total alkoxysilane in an amount of 40 to 99.5 mol%. 6. The method according to any one of claims 1 to 5,
Wherein the fluorine-containing coating layer is formed of an axial polymer of a perfluoroalkyl or perfluoropolyether silane compound. 7. The method according to any one of claims 1 to 6,
The thickness of the fluorine coating layer is 1 to 30 nm, the thickness of the diamond like carbon layer is 50 to 150 nm, and the thickness of the intermediate layer is 10 to 500 nm. A display device comprising the glass substrate according to any one of claims 1 to 7.

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