Aqueous primer composition, water-repellent article, and method for producing water-repellent article

Abstract

Provided is an aqueous primer composition which is used for forming a primer layer of a water-repellent article, which has the primer layer on the outer surface of a base material and also has a water-repellent surface layer on the outer surface of the primer layer. The aqueous primer composition is characterized by containing silica nanoparticles and a metal compound containing one or more of niobium, hafnium, zirconium and tantalum at quantities whereby the mass ratio of the metal compound relative to the silica nanoparticles is not less than 5% and less than 1000%. By forming the primer layer on the surface of the base material using the aqueous primer composition, it is possible to produce a water-repellent article having a water-repellent surface layer that exhibits excellent abrasion resistance and excellent chemical resistance.

Description

Water-based primer composition, water-repellent article and method for producing water-repellent article

[0001] The present invention relates to an aqueous primer composition, and more particularly to an aqueous primer composition used for forming a primer layer of a water-repellent article having a primer layer on the outer surface of a substrate and further having a water-repellent surface layer on the outer surface of the primer layer; a water-repellent article having a primer layer formed using the aqueous primer composition and having a water-repellent surface protective film with excellent abrasion resistance and chemical resistance; and a method for producing the water-repellent article.

[0002] BACKGROUND ART Generally, surfaces of semiconductor manufacturing process components, mold components, precision equipment components, medical equipment parts, automobile parts, building materials, home appliances, office automation equipment, and household goods are subjected to water-repellent treatment to protect the products.

[0003] For water-repellent treatment, alkyl group-containing silane compounds (Patent Documents 1 and 2: JP 2002-038092 A, JP 2021-123678 A) and fluoropolyether group-containing silane compounds (Patent Documents 3 to 8: JP 6260579 A, ​​JP 6828744 A, JP 5761305 A, JP 6451279 A, ​​JP 6741074 A, JP 6617853 A) are used. When these silane compounds are applied and cured to the surface of a substrate such as metal, porcelain, glass, or plastic, a water-repellent layer is formed on the surface of the substrate, imparting to the substrate the ability to prevent dust, fingerprints, and other stains.

[0004] The silane compound has an organic functional group and a reactive silyl group (generally a hydrolyzable silyl group such as an alkoxysilyl group) in one molecule. The hydrolyzable silyl group undergoes a self-condensation reaction in the presence of moisture in the air to form a coating. The hydrolyzable silyl group chemically and physically bonds with the substrate surface, resulting in a durable, strong coating.

[0005] Furthermore, it has been disclosed that friction and wear resistance can be improved by providing a silicon oxide layer between the silane compound and the substrate (Patent Documents 9 to 17: WO 2014 / 097388, JP 2020-132498 A, JP 2020-090652 A, Japanese Patent No. 5655215, Japanese Patent No. 6601492, Japanese Patent No. 5494656, WO 2019 / 035271, WO 2023 / 013476, WO 2023 / 013477).

[0006] However, even when the above-mentioned silane compound and a primer layer of silicon oxide are used in combination, good chemical resistance as well as good abrasion resistance may not be obtained in some cases.

[0007] Japanese Patent Publication No. 2002-038092 Japanese Patent Publication No. 2021-123678 Japanese Patent No. 6260579 Japanese Patent No. 6828744 Japanese Patent No. 5761305 Japanese Patent No. 6451279 Japanese Patent No. 6741074 Japanese Patent No. 6617853 International Publication No. 2014 / 097388 Japanese Patent Publication No. 2020-132498 Japanese Patent Publication No. 2020-090652 Japanese Patent No. 5655215 Japanese Patent No. 6601492 Patent No. 5494656 International Publication No. 2019 / 035271 International Publication No. 2023 / 013476 International Publication No. 2023 / 013477 Special Publication No. 2008-534696 Special Publication No. 2008-537557 Japanese Patent Application Laid-Open No. 2012-072272 Japanese Patent Application Laid-Open No. 2012-157856 Japanese Patent Application Laid-Open No. 2013-136833 Japanese Patent Application Laid-Open No. 9-326240 Japanese Patent No. 4363388 Japanese Patent Application Laid-Open No. 2022-118099

[0008] The present invention has been made in view of the above circumstances, and aims to provide an aqueous primer composition used for forming a primer layer of a water-repellent article having a primer layer on the outer surface of a substrate and further having a water-repellent surface layer on the outer surface of the primer layer; a water-repellent article having a primer layer formed using the aqueous primer composition and having a water-repellent surface protective film with excellent abrasion resistance and chemical resistance; and a method for producing the water-repellent article.

[0009] As a result of intensive research conducted by the present inventors to achieve the above object, they have found that in a water-repellent article comprising a primer layer on the outer surface of a substrate and a water-repellent surface layer on the outer surface of the primer layer, when the primer layer is formed using an aqueous primer composition characterized by containing silica nanoparticles and a metal compound containing one or more of niobium, hafnium, zirconium, and tantalum, the mass ratio of the metal compound to the silica nanoparticles being 5% or more but less than 1000%, it is possible to form a water-repellent surface protective film that is excellent in chemical resistance and abrasion resistance, which has led to the present invention.

[0010] Accordingly, the present invention provides the following aqueous primer composition, water-repellent article, and method for producing a water-repellent article. [1] An aqueous primer composition used to form a primer layer of a water-repellent article having a primer layer on the outer surface of a substrate and a water-repellent surface layer on the outer surface of the primer layer, the aqueous primer composition comprising silica nanoparticles and a metal compound containing one or more of niobium, hafnium, zirconium, and tantalum, the mass ratio of the metal compound to the silica nanoparticles being 5% or more but less than 1000%. [2] The primer composition according to [1], wherein the silica nanoparticles have an average particle size of 0.1 to 50 nm. [3] The primer composition according to [1] or [2], wherein the metal compound is one or more of niobium oxide, ammonium niobium oxalate, and niobium oxalate. [4] The primer composition according to [3], wherein the niobium oxide is niobium oxide nanoparticles having an average particle size of 0.1 to 20 nm. [5] The primer composition according to any one of [1] to [4], wherein the metal compound is one or more of ammonium zirconium carbonate, zirconium acetate, zirconium oxynitrate, zirconium nitrate, zirconium oxychloride, and chlorohydroxyzirconium. [6] The primer composition according to any one of [1] to [5], wherein the substrate is metal. [7] The primer composition according to any one of [1] to [5], wherein the substrate is glass. [8] The primer composition according to any one of [1] to [7], which is used for building materials and housing equipment. [9] The primer composition according to any one of [1] to [7], which is used for touch panels, windows, and lenses.

[10] A water-repellent article having a primer layer having a thickness of 1 to 50 nm on the outer surface of a substrate, the primer layer containing silica nanoparticles and a metal oxide containing one or more of niobium, hafnium, zirconium, and tantalum in total at a ratio of 5% to 1000% by mass of the metal oxide relative to the silica nanoparticles, and a water-repellent surface layer having a thickness of 0.5 to 20 nm on the outer surface of the primer layer.

[11] The water-repellent article according to

[10] , wherein the average particle size of the silica nanoparticles in the primer layer is 0.1 to 50 nm.

[12] The water-repellent article according to

[10] or

[11] , wherein the metal oxide in the primer layer is niobium oxide or zirconium oxide.

[13] The water-repellent surface layer is represented by the following formula (1), (4), or (7): [wherein Rf is a divalent perfluoropolyether group, A 1 is a monovalent fluorine-containing hydrocarbon group whose terminal is CF3- or CF2H- and which may contain an oxygen atom, or D, and D is independently a monovalent group represented by the following formula (2): [In the formula, Q is a single bond or a divalent organic group, Z is a trivalent to octavalent group, α is an integer of 2 to 7, and W is independently a monovalent silanol group or a hydrolyzable silyl group-containing group represented by the following formula (3): (wherein R is an alkyl group having 1 to 4 carbon atoms or a phenyl group, X is independently a hydroxyl group or a hydrolyzable group, a is 2 or 3, and Y is a single bond or a divalent hydrocarbon group which may have one or more bonds selected from a fluorine atom, a silicon atom, and a siloxane bond.) [wherein Rf is the same as above, A 2 is a monovalent fluorine-containing hydrocarbon group whose terminal is CF3- or CF2H- and which may contain an oxygen atom, or G, and G is independently a monovalent group represented by the following formula (5): [In the formula, W is the same as above, B is a hydrogen atom or —OS, and S is a hydrogen atom, a monovalent hydrocarbon group having 1 to 10 carbon atoms, or a monovalent group represented by the following formula (6): (wherein T is a single bond or a divalent group, L is independently a divalent hydrocarbon group having 1 to 4 carbon atoms, E is a monovalent hydrocarbon group having 1 to 6 carbon atoms or W, and l is an integer of 0 to 20.) [wherein Rf is the same as above, A 3 is a monovalent fluorine-containing hydrocarbon group whose terminal is CF3- or CF2H- and which may contain an oxygen atom, or J, each J is independently a monovalent group represented by the following formula (8), and J has two or more Ws: [In the formula, S is the same as defined above, V is a divalent hydrocarbon group having 2 to 15 carbon atoms which may have a single bond or an ether bond, and M is independently a monovalent group represented by the following formula (9): (wherein Y, S, and W are the same as above, and f is an integer of 1 to 3, and e is 1 or 2.) ]].

[14] The water-repellent article according to any one of

[10] to

[12] , wherein the water-repellent surface layer is a cured product of a surface treatment agent containing a fluoropolyether group-containing polymer having one or more silanol groups or hydrolyzable silyl groups and / or a partial (hydrolyzed) condensate thereof, represented by the following formula (11), (12), or (13): (wherein A is a monovalent hydrocarbon group having 1 to 50 carbon atoms, and B 1 is a hydrogen atom or a hydroxyl group, E 1 is a hydrogen atom or a monovalent hydrocarbon group having 1 to 50 carbon atoms, and A and E 1 The total number of carbon atoms contained in Y is 12 or more, 1 is a single bond or a divalent hydrocarbon group which may have one or more bonds selected from silicon atoms and siloxane bonds, R is an alkyl group having 1 to 4 carbon atoms or a phenyl group, and X 1 are independently hydrolyzable groups, and z is 2 or 3. (In the formula, A, B 1 , E 1 , Y 1 is the same as above, y is a number from 0 to 3, x is (3-y) / 2, when y=3, formula (12) represents the molecular formula of the monomer, and when y<3, formula (12) represents the composition formula of the polymer. (In the formula, G 1 are independently monovalent hydrocarbon groups having 8 to 30 carbon atoms; J 1are independently a hydrogen atom, a hydroxyl group, or a methyl group.) The water-repellent article according to any one of

[10] to

[12] , which is a cured product of a surface treatment agent containing a fluorine-free alkyl-containing compound having a hydrolyzable silyl group represented by the formula (I) and / or a partial hydrolysis condensate thereof.

[15] The water-repellent article according to any one of

[10] to

[14] , wherein the substrate is metal.

[16] The water-repellent article according to any one of

[10] to

[14] , wherein the substrate is glass.

[17] The water-repellent article according to any one of

[10] to

[16] , which is used for building materials and housing equipment.

[18] The water-repellent article according to any one of

[10] to

[16] , which is used for touch panels, windows, and lenses.

[19] A method for producing a water-repellent article according to any one of

[10] to

[18] , comprising forming a primer layer by a wet coating method using the primer composition according to any one of [1] to [9], and forming a water-repellent surface layer by the wet coating method.

[20] A method for producing a water-repellent article according to any one of

[10] to

[18] , wherein a primer layer is formed by a wet coating method using the primer composition according to any one of [1] to [9], and a water-repellent surface layer is formed by a dry coating method.

[0011] According to the aqueous primer composition of the present invention, by forming a primer layer on the surface of a substrate using the aqueous primer composition, a water-repellent surface layer (e.g., a cured product of a reactive silyl compound exhibiting surface water repellency) is firmly adhered to the surface of the substrate, and a water-repellent article having a water-repellent surface layer excellent in abrasion resistance and chemical resistance can be produced. The method for producing the water-repellent article can be formed by a wet process without requiring a vacuum process or a high-temperature heating process, and can be applied to a variety of applications.

[0012] In the present invention, the term "partial (hydrolyzed) condensate" refers to a partial condensate or a partial hydrolyzed condensate.

[0013] The present invention will be described in further detail below. [Water-based primer composition] The water-based primer composition of the present invention is used for forming a primer layer of a water-repellent article having a primer layer on the outer surface of a substrate and further having a water-repellent surface layer on the outer surface of the primer layer, and contains silica nanoparticles and a metal compound containing one or more of niobium, hafnium, zirconium, and tantalum, in which the mass ratio of the metal compound to the silica nanoparticles is 5% or more but less than 1000%.

[0014] In the aqueous primer composition of the present invention, the silica nanoparticles preferably have an average particle size (diameter) of 50 nm or less, more preferably 20 nm or less, and even more preferably 10 nm or less. If the average particle size of the silica nanoparticles is too large, the number of contact points between the substrate and the silica nanoparticles may decrease, resulting in poor adhesion to the substrate. The lower limit of the average particle size is usually 0.1 nm or more, preferably 0.5 nm or more. If the average particle size of the silica nanoparticles is too small, the mechanical strength of the primer layer may decrease. In the present invention, the average particle size can be determined, for example, as the hydrodynamic average diameter by dynamic light scattering in accordance with JIS Z 8828:2019.

[0015] The silica nanoparticles used in the present invention may be commercially available products dispersed in water, such as Snowtex (manufactured by Nissan Chemical Industries, Ltd.).

[0016] The content of silica nanoparticles in the aqueous primer composition is preferably 0.01 to 10% by mass, more preferably 0.1 to 1% by mass. If the amount of silica nanoparticles is too small, the uncoated areas will increase, while if the amount of silica nanoparticles is too large, aggregation (phase separation) may occur.

[0017] In the aqueous primer composition of the present invention, examples of the metal compound containing one or more of niobium, hafnium, zirconium, and tantalum include a metal compound containing niobium, a metal compound containing hafnium, a metal compound containing zirconium, and a metal compound containing tantalum.

[0018] Examples of metal compounds containing niobium include niobium oxide, ammonium niobium oxalate, and niobium oxalate. Here, the niobium oxide is preferably niobium oxide nanoparticles, and the average particle size (diameter) of the niobium oxide nanoparticles is preferably 20 nm or less, more preferably 10 nm or less. If the average particle size of the niobium oxide nanoparticles is too large, the number of contact points between the substrate and the niobium oxide nanoparticles may decrease, resulting in poor adhesion to the substrate. The lower limit of the average particle size is usually 0.1 nm or more, preferably 0.5 nm or more. If the average particle size of the niobium oxide nanoparticles is too small, the mechanical strength of the primer layer may be reduced. In the present invention, the average particle size can be determined, for example, as the hydrodynamic average diameter by dynamic light scattering in accordance with JIS Z 8828:2019.

[0019] Examples of metal compounds containing hafnium include hafnium acetate and hafnium oxalate.

[0020] Examples of the metal compound containing zirconium include ammonium zirconium carbonate, zirconium acetate, zirconium oxynitrate, zirconium nitrate, zirconium oxychloride, and chlorohydroxyzirconium.

[0021] An example of a metal compound containing tantalum is tantalum oxalate.

[0022] In the aqueous primer composition of the present invention, the metal compound containing at least one of niobium, hafnium, zirconium, and tantalum is preferably a metal compound containing niobium or a metal compound containing zirconium, and more preferably niobium oxide nanoparticles or ammonium zirconium carbonate. The niobium oxide nanoparticles and ammonium zirconium carbonate used in the present invention can be commercially available products in the form of a dispersion in water or an aqueous solution. For example, Baylar Nb (manufactured by Taki Chemical Co., Ltd.) is a commercially available product in the form of a dispersion of niobium oxide nanoparticles in water, and Baycoat (manufactured by Nippon Light Metal Co., Ltd.) is a commercially available product in the form of an aqueous solution of ammonium zirconium carbonate.

[0023] The content of the metal compound in the aqueous primer composition is preferably 0.01 to 10% by mass, more preferably 0.1 to 1% by mass. If the amount of the metal compound is too small, the amount of uncoated areas will increase, while if the amount of the metal compound is too large, aggregation (phase separation) may occur. The content of the metal compound is determined from the particle mass for niobium oxide, and for metal compounds other than niobium oxide, it is determined as a metal oxide equivalent value by chelate titration.

[0024] In the aqueous primer composition of the present invention, the mass ratio of the metal compound to the silica nanoparticles in the primer composition is 5% or more and less than 1000%, and preferably 100% or more and 800% or less. If the mass ratio of the metal compound is too low, the resulting water-repellent article will not have sufficient chemical resistance, and if the mass ratio of the metal compound is too high, the resulting water-repellent article will not have sufficient abrasion durability.

[0025] In the aqueous primer composition of the present invention, the solvent for dispersing or dissolving the silica nanoparticles and the metal compound is an aqueous solvent, preferably pure water or an alkaline aqueous solution such as an aqueous sodium hydroxide solution or an aqueous ammonia solution. The pH range is preferably 7 to 11, particularly preferably 8 to 10.

[0026] In the aqueous primer composition of the present invention, the total content of silica nanoparticles and the metal compound is 50 to 100% by mass, preferably 60 to 100% by mass, based on the solid content of the aqueous primer composition. If the total content is less than 50% by mass, the abrasion resistance and chemical resistance of the resulting water-repellent article will be poor. The total content of silica nanoparticles and the metal compound may be 100% by mass, but since voids may be easily formed, the degree of filling may be increased by mixing other particles with small particle sizes.

[0027] The aqueous primer composition of the present invention may contain particles other than silica nanoparticles and the above-mentioned metal compounds. Examples of such particles other than silica nanoparticles and the above-mentioned metal compounds include nanoparticles of titanium oxide, tin oxide, silver, platinum, copper, alumina, calcium oxide, magnesium oxide, manganese oxide, nickel oxide, and multicomponent oxides (excluding the above-mentioned metal compounds), each having an average particle size of preferably 30 nm or less, more preferably 20 nm or less, and even more preferably 1 to 10 nm. Among these, titanium oxide nanoparticles, platinum nanoparticles, and tin oxide nanoparticles are preferred. These may be used alone or in combination of two or more. When these particles are used, they are preferably contained in an amount of 0.1 to 50% by mass, particularly 1 to 20% by mass, of the solid content of the aqueous primer composition.

[0028] Furthermore, the aqueous primer composition of the present invention may contain surfactants such as ultraviolet absorbers, light stabilizers, antioxidants, leveling agents, antifoaming agents, pigments, dyes, dispersants, antistatic agents, and antifogging agents, as needed, within the scope of not impairing the object of the present invention.

[0029] The aqueous primer composition of the present invention can be prepared by mixing silica nanoparticles, a metal compound containing one or more of niobium, hafnium, zirconium, and tantalum, an aqueous solvent, and, if necessary, other components to form a dispersion.

[0030] [Water-repellent article] The present invention further provides a water-repellent article comprising a primer layer having a thickness of 1 to 50 nm on the outer surface of a substrate, the primer layer containing silica nanoparticles and a metal oxide containing one or more of niobium, hafnium, zirconium, and tantalum in total at a ratio of 5% to 1000% by mass of the metal oxide relative to the silica nanoparticles, and a water-repellent surface layer having a thickness of 0.5 to 20 nm on the outer surface of the primer layer.

[0031] The water-repellent article of the present invention can be obtained by a manufacturing method that includes wet-coating, onto the outer surface of a substrate, an aqueous primer composition containing the above-mentioned silica nanoparticles and a metal compound containing one or more of niobium, hafnium, zirconium, and tantalum, in which the mass ratio of the metal compound to the silica nanoparticles is 5% or more but less than 1000%, followed by drying and removing the solvent from the composition to form a primer layer on the outer surface of the substrate, and further wet- or dry-coating, onto the outer surface of the primer layer, a surface treatment agent containing a reactive silyl compound, followed by drying and removing the solvent from the surface treatment agent and curing the reactive silyl compound to form a water-repellent surface layer on the outer surface of the primer layer.

[0032] [Substrate] Examples of the substrate used in the water-repellent article of the present invention include glass and metal. Examples of glass include soda-lime glass, crown glass, lead glass, borosilicate glass, crystallized glass, quartz glass, aluminosilicate glass, Tempax, Pyrex (registered trademark), Neoceram, etc., but are not limited to these. The glass may be chemically or physically strengthened. The shape of the glass substrate may be a plate, a film, or other form.

[0033] Examples of the metal include, but are not limited to, pure metals such as aluminum, titanium, chromium, iron, cobalt, zinc, nickel, and copper, alloys such as stainless steel (e.g., SUS304 mirror finish), brass, Kovar, and Inconel, and those plated with zinc, nickel, chromium, etc. The shape of the metal substrate may be a plate, rod, sphere, or other shape.

[0034] The substrate may be pretreated before coating with the primer layer. The pretreatment method is not particularly limited as long as it can remove contaminants from the substrate surface and hydrophilize the substrate surface. Examples of pretreatment methods include alcohol cleaning treatment using alcohol such as ethanol or 2-propanol, alkali cleaning treatment using an alkaline cleaner, plasma cleaning treatment using oxygen or argon plasma, and radical cleaning treatment using OH radicals. These methods may also be used in combination. An alkali cleaning treatment using an alkaline cleaner or a plasma cleaning treatment using plasma is preferred, and it is more preferred to perform an alkali cleaning treatment using an alkaline cleaner followed by a plasma cleaning treatment using plasma.

[0035] The effect of the pretreatment of the substrate can be confirmed by the degree of hydrophilicity of the substrate surface. The hydrophilicity can be evaluated by the contact angle of water on the substrate, which is preferably 40° or less, more preferably 20° or less, and even more preferably 10° or less. The contact angle of water is measured in accordance with JIS R 3257:1999.

[0036] In the present invention, a functional layer may be formed between the substrate and the primer layer. Examples of the functional layer include an anti-reflection film layer.

[0037] [Primer Layer] The primer layer constituting the water-repellent article of the present invention is a primer layer having a film thickness of 1 to 50 nm, which contains a total of 50 mass% or more of silica nanoparticles and a metal oxide containing one or more of niobium, hafnium, zirconium, and tantalum, and in which the mass ratio of the metal oxide to the silica nanoparticles is 5% or more but less than 1000%, and which can be formed using the above-mentioned aqueous primer composition of the present invention.

[0038] The primer layer can be formed by applying the aqueous primer composition to the surface of a substrate by a wet coating method, particularly by dipping, brushing, spin coating, spray coating, flow coating, or the like, and then drying the solvent. To increase the density of the primer layer, it is advisable to heat the primer layer at 50 to 500°C for 10 minutes to 24 hours, within a temperature range that does not affect the substrate. If the metal compound is not a metal oxide, it will become a metal oxide at this stage.

[0039] The thickness of the primer layer formed on the substrate surface is selected appropriately depending on the type of substrate, but is usually 1 to 50 nm, preferably 1 to 20 nm, and particularly preferably 1 to 10 nm. If the thickness is thinner than this range, the surface coverage may be insufficient, resulting in insufficient adhesion of the water-repellent surface layer. If the thickness is thicker than this range, poor appearance such as haze or color change may occur. In the present invention, the thickness can be measured by X-ray reflectance measurement, spectroscopic ellipsometry measurement, or the like.

[0040] The resulting primer layer is a metal oxide-silica mixed primer layer, containing silica nanoparticles and a metal oxide containing one or more of niobium, hafnium, zirconium, and tantalum in a total amount of 50% by mass or more (50 to 100% by mass), preferably 60 to 100% by mass. If the content is less than 50% by mass, the abrasion durability and chemical resistance of the resulting water-repellent article will be poor. Furthermore, in the resulting primer layer, the mass ratio of the metal oxide to the silica nanoparticles is 5% or more but less than 1000%, preferably 100% or more and 800% or less. If the mass ratio of the metal oxide is too low, the resulting water-repellent article will not have sufficient chemical resistance, and if the mass ratio of the metal oxide is too high, the resulting water-repellent article will not have sufficient abrasion durability.

[0041] [Water-repellent surface layer] The water-repellent surface layer constituting the water-repellent article of the present invention is a water-repellent surface layer having a film thickness of 0.5 to 20 nm formed on the outer surface of the primer layer. The water-repellent surface layer is preferably formed from a cured product of a surface treatment agent containing a reactive silyl compound exhibiting surface water repellency, and more preferably formed from a cured product of a surface treatment agent containing a fluoropolyether group-containing polymer having a silanol group or a hydrolyzable silyl group and / or a partial (hydrolyzed) condensate thereof, or a cured product of a surface treatment agent containing a fluorine-free alkyl group-containing compound having a hydrolyzable silyl group and / or a partial hydrolyzed condensate thereof.

[0042] <Surface Treatment Agent Comprising Fluoropolyether Group-Containing Polymer Having Silanol Group or Hydrolyzable Silyl Group and / or Partial (Hydrolyzed) Condensate Thereof> As the fluoropolyether group-containing polymer having a silanol group or a hydrolyzable silyl group, it is preferred to use one or more fluoropolyether group-containing polymers represented by the following formula (1), (4) or (7). In particular, it is preferred to use a fluoropolyether group-containing polymer represented by the following formula (4). [wherein Rf is a divalent perfluoropolyether group, A 1 is a monovalent fluorine-containing hydrocarbon group whose terminal is CF3- or CF2H- and which may contain an oxygen atom, or D, and D is independently a monovalent group represented by the following formula (2): [In the formula, Q is a single bond or a divalent organic group, Z is a trivalent to octavalent group, α is an integer of 2 to 7, and W is independently a monovalent silanol group or a hydrolyzable silyl group-containing group represented by the following formula (3): (wherein R is an alkyl group having 1 to 4 carbon atoms or a phenyl group, X is independently a hydroxyl group or a hydrolyzable group, a is 2 or 3, and Y is a single bond or a divalent hydrocarbon group which may have one or more bonds selected from a fluorine atom, a silicon atom, and a siloxane bond.) [wherein Rf is the same as above, A 2 is a monovalent fluorine-containing hydrocarbon group whose terminal is CF3- or CF2H- and which may contain an oxygen atom, or G, and G is independently a monovalent group represented by the following formula (5): [In the formula, W is the same as above, B is a hydrogen atom or —OS, and S is a hydrogen atom, a monovalent hydrocarbon group having 1 to 10 carbon atoms, or a monovalent group represented by the following formula (6): (wherein T is a single bond or a divalent group, L is independently a divalent hydrocarbon group having 1 to 4 carbon atoms, E is a monovalent hydrocarbon group having 1 to 6 carbon atoms or W, and l is an integer of 0 to 20.) [wherein Rf is the same as above, A 3is a monovalent fluorine-containing hydrocarbon group whose terminal is CF3- or CF2H- and which may contain an oxygen atom, or J, each J is independently a monovalent group represented by the following formula (8), and J has two or more Ws: [In the formula, S is the same as defined above, V is a divalent hydrocarbon group having 2 to 15 carbon atoms which may have a single bond or an ether bond, and M is independently a monovalent group represented by the following formula (9): (wherein Y, S, and W are the same as above, f is an integer of 1 to 3, and e is 1 or 2.)

[0043] First, the fluoropolyether group-containing polymer represented by the following formula (1) will be described.

[0044] In the above formula (1), Rf is a divalent perfluoropolyether group, preferably -C d F 2d -O-(CF2O) p (C2F4O) q (C3F6O) r (C4F8O) s (C5F 10 O) t (C6F 12 O) u -C d F 2d - is a divalent perfluoropolyether group represented by the formula (I), and d is independently an integer of 0 to 5, preferably an integer of 0 to 2, and more preferably 0 or 1 for each unit. p, q, r, s, t, and u are each independently an integer of 0 to 150, preferably an integer of 0 to 100, and more preferably an integer of 0 to 60, and the sum of p, q, r, s, t, and u is an integer of 1 to 250, preferably an integer of 3 to 140, and more preferably an integer of 7 to 70. Each of these units may be linear or branched. Note that the repeating units shown in parentheses with p, q, r, s, t, and u may be randomly bonded.

[0045] The divalent perfluoropolyether group represented by Rf can be specifically represented by the following structure. (In the formula, p', q', r', s', t', and u' each independently represent an integer of 1 to 150, the sum of p', q', r', s', t', and u' is 12 to 250, and each of these units may be linear or branched. Furthermore, each of the repeating units shown in parentheses followed by p', q', r', s', t', and u' may be bonded randomly. d' is independently an integer of 0 to 5 for each unit. Each of these units may be linear or branched.)

[0046] The above formula (1); A 1 - In Rf-D, A 1 represents a monovalent fluorine-containing hydrocarbon group having a terminal CF3- or CF2H- and optionally containing an oxygen atom, or D (i.e., a group represented by the formula (2) below): -Q-Z(W) α The monovalent fluorine-containing hydrocarbon group which is a CF3- or CF2H- group and which may contain an oxygen atom and has a terminal CF3- or CF2H- is preferably a fluoroalkyl group having 1 to 6 carbon atoms, and particularly preferably one which ends in a polymer with a terminal CF3- or CF2H-.

[0047] Such an A 1 Examples of the monovalent fluorine-containing hydrocarbon group which has a terminal group of CF3- or CF2H- and may contain an oxygen atom include the following groups:

[0048] The above formula (1); A 1 In —Rf-D, D is independently a monovalent group represented by the following formula (2).

[0049] In the above formula (2), Q is a single bond or a divalent organic group, and Q other than a single bond is preferably an unsubstituted or substituted divalent hydrocarbon group having 1 to 15 carbon atoms, preferably 2 to 15 carbon atoms, which may contain one or more bonds selected from the group consisting of an amide bond (e.g., an unsubstituted amide bond, an N-methyl-substituted amide bond, an N-phenyl-substituted amide bond), an ether bond, an ester bond, a sulfide bond, a urethane bond, a siloxane bond, a triazine bond, a diorganosilylene group (e.g., a dialkylsilylene group such as a dimethylsilylene group), a silarylene bond (e.g., a silphenylene bond), and a silalkylene bond (e.g., a silethylene bond), and is preferably an unsubstituted or fluorine-substituted divalent hydrocarbon group having 1 to 12 carbon atoms, preferably 2 to 12 carbon atoms, which may contain the above bond.

[0050] Here, examples of the silalkylene bond and silarylene bond include those shown below. (In the formula, R 1 is an alkyl group having 1 to 8 carbon atoms, such as a methyl group, an ethyl group, a propyl group, or a butyl group, and more preferably an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 10 carbon atoms, such as a phenyl group; R 1 may be the same or different. 2 represents an alkylene group having 1 to 4 carbon atoms, such as a methylene group, an ethylene group, or a propylene group (trimethylene group, methylethylene group), or an arylene group having 6 to 10 carbon atoms, such as a phenylene group.

[0051] Examples of Q other than a single bond include the following groups: In the following structure, it is preferred that the left bond is bonded to Rf and the right bond is bonded to Z. (In the formula, b is an integer of 2 to 4.)

[0052] The above formula (2); -Q-Z(W) αIn the formula, Z is a trivalent to octavalent group, preferably a trivalent to octavalent, preferably tri- or tetravalent group selected from trivalent to octavalent organopolysiloxane residues having a silicon atom, a nitrogen atom, and a siloxane bond, preferably a linear, branched, or cyclic organopolysiloxane residue having 3 to 13 silicon atoms, more preferably 3 to 5 silicon atoms. Also preferred are silalkylene structures such as a silethylene structure in which two silicon atoms are bonded via an alkylene group such as an ethylene group, i.e., Si-(CH2) n It may contain —Si (in the above formula, n is an integer of 2 to 6, preferably an integer of 2 to 4).

[0053] Examples of the trivalent to octavalent organopolysiloxane residue having a siloxane bond include those shown below. (In the formula, R 1 is the same as above. g is an integer of 3 to 12, preferably 3 or 4, h is an integer of 3 to 8, preferably 3 or 4, j is an integer of 0 to 8, preferably 0 or 1, h+j is an integer of 3 to 13, preferably an integer of 3 to 5, and k is 2 or 3. [In the formula, R 4 are independently R 1 Or the following formula (a): (In the formula, R 1 is the same as above, j' is an integer of 1 to 6, preferably 1, and the bond on the left side is bonded to Si. 5 are independently a single bond or a group represented by the following formula (b): (In the formula, R 2 , R 4 is the same as above, j" is an integer of 0 to 6, preferably an integer of 0 to 3, j'" is an integer of 0 to 6, preferably an integer of 0 to 2, and each repeating unit shown in parentheses may be bonded randomly. The bond on the left side is bonded to Si.) and R 4 At least one of the formulas is formula (a).

[0054] Examples of such Z include the following: In the following structure, it is preferred that the bond on the left side is bonded to Q, and the other bond is bonded to W.

[0055] The above formula (2); -Q-Z(W) α In the formula (3), W is independently a monovalent silanol group or a hydrolyzable silyl group-containing group represented by the following formula (3): (In the formula, R is an alkyl group having 1 to 4 carbon atoms or a phenyl group, X is independently a hydroxyl group or a hydrolyzable group, a is 2 or 3, and Y is a single bond or a divalent hydrocarbon group which may have one or more bonds selected from a fluorine atom, a silicon atom, and a siloxane bond.)

[0056] In the above formula (3), X's are hydroxyl groups or hydrolyzable groups, which may be different from one another. Examples of such X's include hydroxyl groups, alkoxy groups having 1 to 10 carbon atoms such as methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, sec-butoxy, and tert-butoxy groups, alkoxy-substituted alkoxy groups having 2 to 10 carbon atoms such as methoxymethoxy, methoxyethoxy, ethoxymethoxy, and ethoxyethoxy groups, acyloxy groups having 2 to 10 carbon atoms such as acetoxy and propionoxy groups, alkenyloxy groups having 2 to 10 carbon atoms such as vinyloxy, allyloxy, propenoxy, and isopropenoxy groups, and halogen groups such as chlorine, bromo, and iodo groups. Among these, methoxy, ethoxy, isopropenoxy, and chlorine groups are preferred.

[0057] In the above formula (3), R is an alkyl group having 1 to 4 carbon atoms, such as a methyl group, an ethyl group, a propyl group, or a butyl group, or a phenyl group, of which a methyl group or an ethyl group is preferred. In the above formula (3), a is 2 or 3, and is preferably 3 from the viewpoints of reactivity and adhesion to the substrate.

[0058] In the above formula (3), Y is a single bond or a divalent hydrocarbon group having 1 to 20 carbon atoms which may have one or more bonds selected from a fluorine atom, a silicon atom, and a siloxane bond, and the divalent hydrocarbon group which may have one or more bonds selected from a fluorine atom, a silicon atom, and a siloxane bond is a group selected from the group consisting of an alkylene group having 1 to 10 carbon atoms, an alkylene group having 1 to 10 carbon atoms and containing a fluorine atom, an alkylene group containing an arylene group having 6 to 8 carbon atoms (alkylene-arylene group), a divalent group in which alkylene groups are mutually bonded via a silalkylene structure or a silarylene structure, and a divalent group in which an alkylene group having 2 to 10 carbon atoms is bonded to a bond of a linear divalent organopolysiloxane residue having 2 to 10 silicon atoms or a branched or cyclic divalent organopolysiloxane residue having 3 to 10 silicon atoms.

[0059] Specific examples of Y other than a single bond include the following: In the following structure, it is preferable that the bond on the right side is bonded to the silicon atom.

[0060] Examples of the group in the above formula (3) include the following.

[0061] The above formula (2); -Q-Z(W) α In the formula, α, which indicates the number of Ws, is an integer of 2 to 7.

[0062] The group in the above formula (2): -Q-Z(W) α (i.e., D in formula (1)) includes the following.

[0063] Examples of the fluoropolyether group-containing polymer represented by the above formula (1) include the following. (In the formula, A 1 , Rf is the same as above.)

[0064] Next, the fluoropolyether group-containing polymer represented by the following formula (4) will be described. In the above formula (4), Rf is the same as above, and examples thereof include the same as those exemplified for Rf in the above formula (1).

[0065] The above formula (4); A 2 In Rf-G, A 2 is a monovalent fluorine-containing hydrocarbon group which terminates in CF3- or CF2H- and which may contain an oxygen atom, or G (i.e., a monovalent group represented by formula (5); -C(B)(W)2 described below), and the monovalent fluorine-containing hydrocarbon group which terminates in CF3- or CF2H- and which may contain an oxygen atom is preferably a fluoroalkyl group having 1 to 6 carbon atoms, and particularly preferably one which terminates in CF3- or CF2H- of the polymer.

[0066] Such an A 2 Examples of the monovalent fluorine-containing hydrocarbon group which has a terminal group of CF3- or CF2H- and may contain an oxygen atom include the following groups:

[0067] The above formula (4); A 2 In —Rf-G, G is independently a monovalent group represented by the following formula (5). In the above formula (5), W is the same as above, and examples thereof include those similar to those exemplified for W in the above formula (2).

[0068] In the above formula (5); -C(B)(W)2, B is a hydrogen atom or -OS, and S is a hydrogen atom, a monovalent hydrocarbon group having 1 to 10 carbon atoms, or a monovalent group represented by the following formula (6):

[0069] Here, examples of the monovalent hydrocarbon group having 1 to 10 carbon atoms represented by S include alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, and octyl groups; alkenyl groups such as vinyl and allyl groups; aryl groups such as phenyl and tolyl groups; and aralkyl groups such as benzyl and phenylethyl groups, with alkyl groups having 1 to 3 carbon atoms and phenyl groups being preferred.

[0070] The above formula (6); -T-(LO) lIn -E, T represents a single bond or a divalent group, and is preferably a single bond, or a divalent hydrocarbon group having 2 to 20 carbon atoms which may contain one or more bonds selected from the group consisting of a silicon atom, a siloxane bond, a silalkylene bond (e.g., a silethylene bond or a silpropylene bond), a silarylene bond (e.g., a silphenylene bond), and a diorganosilylene group (e.g., a dialkylsilylene group such as a dimethylsilylene group, or a dialkoxysilylene group such as a dimethoxysilylene group), and specific examples of T other than a single bond include those shown below. In the following structure, it is preferable that the bond on the right is bonded to L or E.

[0071] The above formula (6); -T-(LO) l In -E, L is independently a divalent hydrocarbon group having 1 to 4 carbon atoms, such as an alkylene group, including a methylene group, an ethylene group, a propylene group (trimethylene group, methylethylene group), a butylene group (tetramethylene group), etc., and the number of carbon atoms in each (LO) unit may be a single group or a mixture of groups. l In -E, l is an integer of 0 to 20, preferably an integer of 0 to 10, more preferably an integer of 0 to 6. When (LO) is present, l is preferably 1 or more, particularly preferably 2 or more. The above formula (6); -T-(LO) l In -E, E is an alkyl group having 1 to 4 carbon atoms, such as a methyl group, an ethyl group, a propyl group, or a butyl group, or a monovalent hydrocarbon group having 1 to 6 carbon atoms, such as a phenyl group, or W, where W is the same as defined above and can be exemplified by the same groups as those exemplified for W in formula (2) above.

[0072] The above formula (6); -T-(LO) l Examples of the monovalent group represented by -E include those shown below.

[0073] Examples of the monovalent group represented by -C(B)(W)2 in the above formula (5) (i.e., G in formula (4)) include those shown below.

[0074] Examples of the fluoropolyether group-containing polymer represented by the above formula (4) include the following. (In the formula, A 2 , Rf is the same as above.)

[0075] Next, the fluoropolyether group-containing polymer represented by the following formula (7) will be described. In the above formula (7), Rf is the same as above, and examples thereof include the same as those exemplified for Rf in the above formula (1).

[0076] The above formula (7); A 3 In Rf-J, A 3 is a monovalent fluorine-containing hydrocarbon group whose terminal is CF3- or CF2H- and which may contain an oxygen atom, or J (i.e., the group represented by the formula (8) below; -VC(=O)N(S) 2-e (M) e The monovalent fluorine-containing hydrocarbon group which is a CF3- or CF2H- group and which may contain an oxygen atom and has a terminal CF3- or CF2H- is preferably a fluoroalkyl group having 1 to 6 carbon atoms, and particularly preferably one which ends in a polymer with a terminal CF3- or CF2H-.

[0077] Such an A 3 Examples of the monovalent fluorine-containing hydrocarbon group which has a terminal group of CF3- or CF2H- and may contain an oxygen atom include the following groups:

[0078] The above formula (7); A 3 In —Rf-J, J is independently a monovalent group represented by the following formula (8), and J has two or more Ws.

[0079] In the above formula (8), S is the same as above, and examples thereof include the same as those exemplified for S above.

[0080] In the above formula (8), V is a divalent hydrocarbon group having 2 to 15 carbon atoms which may have a single bond or an ether bond, and specific examples of V other than a single bond include those shown below. In the following structure, it is preferable that the bond on the right side is bonded to a carbon atom (-C(=O)-). In the above formula (8), e is 1 or 2, and preferably 1. In the above formula (8), M is independently a monovalent group represented by the following formula (9).

[0081] In the formula (9), Y, S, and W are the same as those described above, and examples thereof include the same as those given as examples of Y in the formula (3), S in the formula (2), and W in the formula (2). In the formula (9), f is an integer of 1 to 3.

[0082] The above formula (9); -Y-C(S) 3-f (W) f Examples of the monovalent group represented by the formula (i.e., M in formula (8)) include those shown below.

[0083] Above formula (8); -VC(=O)N(S) 2-e (M) e Examples of the monovalent group represented by the formula (i.e., J in formula (7)) include those shown below.

[0084] Examples of the fluoropolyether group-containing polymer represented by the above formula (7) include the following. (In the formula, A 3 , Rf is the same as above.)

[0085] The surface treatment agent containing a fluoropolyether group-containing polymer having a silanol group or a hydrolyzable silyl group and / or a partial (hydrolyzed) condensate thereof may further contain, in addition to the above-mentioned fluoropolyether group-containing polymer having a silanol group or a hydrolyzable silyl group and / or a partial (hydrolyzed) condensate thereof, a fluoropolyether group-containing polymer not containing a hydrolyzable silyl group represented by the following formula (10) (hereinafter referred to as a polymer not containing a hydrolyzable silyl group) and / or a partial (hydrolyzed) condensate thereof. [In the formula, Rf is the same as above, and examples thereof include the same as those exemplified as Rf in formula (1) above. 4each independently represents a monovalent fluorine-containing hydrocarbon group which has a terminal CF3- or CF2H- and which may contain an oxygen atom; -OR 3 , -COOR 3 Or -PO(OR 3 ) 2 (R 3 is a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms.

[0086] In the above formula (10), A 4 each independently represents a monovalent fluorine-containing hydrocarbon group which has a terminal CF3- or CF2H- and which may contain an oxygen atom; -OR 3 , -COOR 3 Or -PO(OR 3 ) 2, and the monovalent fluorine-containing hydrocarbon group having a terminal CF3- or CF2H- and optionally containing an oxygen atom includes A 1 The terminal of R is CF3- or CF2H- and may contain an oxygen atom, and the same fluorine-containing monovalent hydrocarbon group as those exemplified above can be used. 3 is a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms. Examples of the monovalent hydrocarbon group include alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, and octyl groups, alkenyl groups such as vinyl and allyl groups, aryl groups such as phenyl and tolyl groups, and aralkyl groups such as benzyl and phenylethyl groups. R 3 is preferably a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or a phenyl group. 4 -OR 3 , -COOR 3 , -PO(OR 3 )2 includes, for example, —OH, —OCH3, —COOH, —COOCH3, —PO(OH)2, —OC2H5, and —COOC2H5.

[0087] Examples of the fluoropolyether group-containing polymer represented by the above formula (10) include the following. (In the formula, p", q", r", s", t", and u" each independently represent an integer of 0 to 150, the sum of p", q", r", s", t", and u" is 12 to 250, and each of these units may be linear or branched. Furthermore, each repeating unit shown in parentheses with p", q", r", s", t", and u" may be bonded randomly.)

[0088] The surface treatment agent containing a fluoropolyether group-containing polymer having a silanol group or a hydrolyzable silyl group and / or its partial (hydrolysis) condensate is preferably at least one of the fluoropolyether group-containing polymer having at least two silanol groups or hydrolyzable silyl groups at one molecular chain end, as represented by the above formula (1), (4) or (7), and / or the partial (hydrolysis) condensate of the polymer (single-end polymer), or at least one of the fluoropolyether group-containing polymer having at least two silanol groups or hydrolyzable silyl groups at each of the molecular chain ends, as represented by the above formula (1), (4) or (7), and / or the partial (hydrolysis) condensate of the polymer (double-end polymer), or at least one of the single-end polymer and at least one double-end polymer, or at least one of these, further containing a mixture containing a polymer not containing a hydrolyzable silyl group (hereinafter referred to as a fluoropolyether group-containing polymer composition).

[0089] In a surface treatment agent containing a fluoropolyether group-containing polymer having a silanol group or a hydrolyzable silyl group and / or a partial (hydrolyzed) condensate thereof, when the polymer does not contain a hydrolyzable silyl group, the mixing ratio of the one-terminal polymer and / or both-terminal polymer to the polymer not containing a hydrolyzable silyl group is not particularly limited, but usually, the ratio of the polymer not containing a hydrolyzable silyl group to the entire fluoropolyether group-containing polymer composition consisting of the one-terminal polymer and / or both-terminal polymer and the polymer not containing a hydrolyzable silyl group is desirably 0.01 to 30 mol %, particularly 0.1 to 10 mol %.

[0090] In the surface treatment agent containing a fluoropolyether group-containing polymer having a silanol group or a hydrolyzable silyl group and / or a partial (hydrolyzed) condensate thereof, the number average molecular weight of the fluoropolyether group-containing polymer having a silanol group or a hydrolyzable silyl group and / or a partial (hydrolyzed) condensate thereof, or the fluoropolyether group-containing polymer composition, is preferably in the range of 1,000 to 20,000. The number average molecular weight is more preferably 2,000 to 10,000, and particularly preferably 3,000 to 8,000. The number average molecular weight is 19 It can be calculated from the characteristic peak intensity ratio in F-NMR analysis.

[0091] The fluoropolyether group-containing polymer and / or its partial (hydrolysis) condensate, or the fluoropolyether group-containing polymer composition, which has silanol group or hydrolyzable silyl group and is within the above-mentioned number-average molecular weight range, can be obtained by rectification or molecular distillation of the fluoropolyether group-containing polymer and / or its partial (hydrolysis) condensate, or the fluoropolyether group-containing polymer composition, which has silanol group or hydrolyzable silyl group and / or its partial (hydrolysis) condensate.In addition, the fluoropolyether group-containing polymer and / or its partial (hydrolysis) condensate, or the fluoropolyether group-containing polymer composition, which has silanol group or hydrolyzable silyl group and is within the above-mentioned number-average molecular weight range, can also be prepared by using the fluorine compound used in synthesizing the fluoropolyether group-containing polymer in advance, which has the above-mentioned number-average molecular weight.

[0092] If necessary, a hydrolysis condensation catalyst such as an organotin compound (dibutyltin dimethoxide, dibutyltin dilaurate, etc.), an organotitanium compound (tetra n-butyl titanate, etc.), an organic acid (acetic acid, methanesulfonic acid, fluorine-modified carboxylic acid, etc.), or an inorganic acid (hydrochloric acid, sulfuric acid, etc.) may be added to the surface treatment agent containing a fluoropolyether group-containing polymer having silanol groups or hydrolyzable silyl groups and / or a partial (hydrolysis) condensate thereof. Of these, acetic acid, tetra n-butyl titanate, dibutyltin dilaurate, fluorine-modified carboxylic acid, etc. are particularly desirable. The amount added is a catalytic amount, and is typically 0.01 to 5 parts by mass, particularly 0.1 to 1 part by mass, per 100 parts by mass of the fluoropolyether group-containing polymer having silanol groups or hydrolyzable silyl groups and / or a partial (hydrolysis) condensate thereof.

[0093] Furthermore, the surface treatment agent containing a fluoropolyether group-containing polymer having a silanol group or a hydrolyzable silyl group and / or a partial (hydrolyzed) condensate thereof may contain a solvent. The solvent is preferably a fluorine-modified aliphatic hydrocarbon solvent (perfluoroheptane, perfluorooctane, etc.), a fluorine-modified olefin solvent (methoxyperfluoroheptene, etc.), a fluorine-modified aromatic hydrocarbon solvent (m-xylene hexafluoride, benzotrifluoride, 1,3-trifluoromethylbenzene, etc.), a fluorine-modified ether solvent (methyl perfluorobutyl ether, ethyl perfluorobutyl ether, perfluoro(2-butyltetrahydrofuran), etc.), a fluorine-modified alkylamine solvent (perfluorotributylamine, perfluorotripentylamine, etc.), a hydrocarbon solvent (petroleum benzine, mineral spirits, toluene, xylene, etc.), or a ketone solvent (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.). Among these, fluorine-modified solvents (referred to as fluorine-based solvents) are desirable in terms of solubility, wettability, etc., and 1,3-trifluoromethylbenzene, m-xylene hexafluoride, perfluoro(2-butyltetrahydrofuran), perfluorotributylamine, and ethyl perfluorobutyl ether are particularly preferred.

[0094] The above solvents may be used in combination of two or more kinds, and it is preferable to uniformly dissolve the fluoropolyether group-containing polymer having a silanol group or a hydrolyzable silyl group and / or its partial (hydrolyzed) condensate, or the fluoropolyether group-containing polymer composition. The optimal concentration of the fluoropolyether group-containing polymer having a silanol group or a hydrolyzable silyl group and / or its partial (hydrolyzed) condensate to be dissolved in the solvent is not limited and may be appropriately selected depending on the method of use of the surface treatment agent. The concentration is usually 0.01 to 30% by mass, preferably 0.02 to 25% by mass, and more preferably 0.05 to 20% by mass.

[0095] <Surface Treatment Agent Comprising a Fluorine-Atom-Free Alkyl-Containing Compound Having a Hydrolyzable Silyl Group and / or a Partially Hydrolyzed Condensate Thereof> As the fluorine-atom-free alkyl-containing compound having a hydrolyzable silyl group, it is preferred to use a fluorine-atom-free alkyl-containing compound having a hydrolyzable silyl group represented by the following formula (11), (12), or (13) (where formula (12) represents the molecular formula of a monomer or the composition formula of a polymer). In particular, a compound represented by the following formula (11) is preferred. (wherein A is a monovalent hydrocarbon group having 1 to 50 carbon atoms, and B 1 is a hydrogen atom or a hydroxyl group, E 1 is a hydrogen atom or a monovalent hydrocarbon group having 1 to 50 carbon atoms, and A and E 1 The total number of carbon atoms contained in Y is 12 or more, 1 is a single bond or a divalent hydrocarbon group which may have one or more bonds selected from silicon atoms and siloxane bonds, R is an alkyl group having 1 to 4 carbon atoms or a phenyl group, and X 1 are independently hydrolyzable groups, and z is 2 or 3. (In the formula, A, B 1 , E 1 , Y 1 is the same as above, y is a number from 0 to 3, x is (3-y) / 2, when y=3, formula (12) represents the molecular formula of the monomer, and when y<3, formula (12) represents the composition formula of the polymer. (In the formula, G 1are independently monovalent hydrocarbon groups having 8 to 30 carbon atoms; J 1 are independently a hydrogen atom, a hydroxyl group, or a methyl group.

[0096] In the above formulas (11) and (12), A is a monovalent hydrocarbon group having 1 to 50 carbon atoms, preferably 10 to 50 carbon atoms, and B 1 is a hydrogen atom or a hydroxyl group, E 1 are hydrogen atoms or monovalent hydrocarbon groups having 1 to 50 carbon atoms, preferably 10 to 50 carbon atoms. 1 Examples of the monovalent hydrocarbon group having 1 to 50 carbon atoms include the following: (In the formula, a1 is an integer of 0 to 49, preferably 9 to 49, and b1 is independently an integer of 1 or more, and the total number of carbon atoms in each structure is 50 or less, preferably 1 to 43.) A is preferably a linear saturated monovalent hydrocarbon group having 10 to 50 carbon atoms, and B 1 is preferably a hydroxyl group, and E 1 is preferably a linear saturated monovalent hydrocarbon group having 10 to 50 carbon atoms. 1 The total number of carbon atoms contained in the formula (I) is 12 or more, preferably 20 to 60.

[0097] In the above formulas (11) and (12), Y 1 is a divalent hydrocarbon group preferably having 1 to 20 carbon atoms, which may have one or more bonds selected from a single bond, a silicon atom, and a siloxane bond. Specific examples of the divalent hydrocarbon group include an alkylene group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, an alkylene group having 1 to 10 carbon atoms including an arylene group having 6 to 8 carbon atoms (for example, an alkylene-arylene group having 7 to 18 carbon atoms), a divalent group in which alkylene groups having 1 to 8 carbon atoms are bonded to each other via a diorganosilylene group, a silalkylene structure, or a silarylene structure, and a divalent group in which an alkylene group having 1 to 10 carbon atoms is bonded to a bond of a linear organopolysiloxane residue having 2 to 10 silicon atoms, preferably 2 to 8 silicon atoms, or a branched or cyclic organopolysiloxane residue having 3 to 10 silicon atoms, preferably 3 to 8 silicon atoms.

[0098] Here, the group bonded to a silicon atom, such as a diorganosilylene group, a silalkylene structure, a silarylene structure, or an organopolysiloxane residue, is preferably an alkyl group having 1 to 8 carbon atoms, preferably 1 to 4 carbon atoms, such as a methyl group, ethyl group, propyl group, or butyl group, or a phenyl group. Furthermore, the alkylene group in the silalkylene structure is preferably an ethylene group, propylene group (trimethylene group, methylethylene group), or butylene group (tetramethylene group, methylpropylene group), each having 2 to 6 carbon atoms, preferably 2 to 4 carbon atoms. Furthermore, the organopolysiloxane residue may contain a silalkylene structure in which two silicon atoms are bonded via an alkylene group, such as an ethylene group or propylene group.

[0099] Such a Y 1 Examples of such groups include the following: In the following structure, it is preferred that the left bond is bonded to a carbon atom and the right bond is bonded to a silicon atom. (In the formula, f1 is independently an integer of 1 to 10, g1 and h1 are each an integer of 1 to 8, and the sum of g1 and h1 is an integer of 2 to 10. j1 is an integer of 1 to 9, and k1 is an integer of 2 to 4.)

[0100] In the above formula (11), X 1 are independently hydrolyzable groups. Examples of the hydrolyzable group include alkoxy groups having 1 to 10 carbon atoms, such as methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, sec-butoxy, and tert-butoxy; alkoxy-substituted alkoxy groups having 2 to 10 carbon atoms, such as methoxymethoxy, methoxyethoxy, ethoxymethoxy, and ethoxyethoxy; acyloxy groups having 2 to 10 carbon atoms, such as acetoxy and propionoxy; alkenyloxy groups having 2 to 10 carbon atoms, such as vinyloxy, allyloxy, propenoxy, and isopropenoxy; and halogen groups, such as chlorine, bromo, and iodo. Of these, methoxy, ethoxy, isopropenoxy, and chlorine are preferred.

[0101] In the above formula (11), R is an alkyl group having 1 to 4 carbon atoms or a phenyl group, of which a methyl group or an ethyl group is preferred. In the above formula (11), z is 2 or 3, preferably 3.

[0102] In the above formula (12), y is a number from 0 to 3 (0 or a positive number of 3 or less), preferably a number from 0 to 2, and more preferably 0. Also, x is (3-y) / 2, preferably 1.5. When y=3, formula (12) represents the molecular formula of a monomer, and when y<3, formula (12) represents the composition formula of a polymer.

[0103] In the above formula (13), G 1 are independently monovalent hydrocarbon groups having 8 to 30 carbon atoms, preferably 10 to 28 carbon atoms, and examples thereof include the following: (In the formula, m1 is an integer of 7 to 29, preferably 9 to 27 carbon atoms, and n1 is an integer of 1 or more, such that the total number of carbon atoms in each structure is 8 to 30, preferably 10 to 28.) In the above formula (13), J 1 are independently a hydrogen atom, a hydroxyl group or a methyl group, and among these, a methyl group is preferred.

[0104] Specific examples of the compound represented by the above formula (11) include octadecyltrimethoxysilane, octadecyltrichlorosilane, octadecyltriethoxysilane, dodecyltrimethoxysilane, triacontyltrichlorosilane, and the compounds shown below.

[0105] Specific examples of the compound represented by the above formula (12) include those shown below.

[0106] Specific examples of the compound represented by the formula (13) include 1,3-dioctadecyl-1,1,3,3-tetramethyldisilazane, 1,3-didodecyl-1,1,3,3-tetramethyldisilazane, 1,3-didecyl-1,1,3,3-tetramethyldisilazane, and 1,3-dioctyl-1,1,3,3-tetramethyldisilazane.

[0107] In the compound represented by the above formula (11), E 1 where R is a monovalent hydrocarbon group having 1 to 50 carbon atoms, can be produced by, for example, the following methods. A hydrocarbon terminal group-containing compound having an alkenyl group at its terminal is mixed with a compound having an SiH group and a hydrolyzable silyl group, and the mixture is subjected to a hydrosilylation addition reaction in the presence of a hydrosilylation catalyst (Preparation Method 1). Alternatively, a hydrocarbon terminal group-containing compound having an SiH group at its terminal is mixed with a compound having an alkenyl group and a hydrolyzable silyl group, and the mixture is subjected to a hydrosilylation addition reaction in the presence of a hydrosilylation catalyst (Preparation Method 2).

[0108] Here, examples of hydrocarbon terminal group-containing compounds having an alkenyl group at the end include compounds represented by the following formula (11a): (In the formula, A, B 1 is the same as above. 1’ is a monovalent hydrocarbon group having 1 to 50 carbon atoms, and A and E 1’ The total number of carbon atoms contained in Y is 12 or more, 1’ may have one or more bonds selected from silicon atoms and siloxane bonds, and is preferably a divalent hydrocarbon group having 1 to 18 carbon atoms.

[0109] In the above formula (11a), E 1’ is a monovalent hydrocarbon group having 1 to 50 carbon atoms, and examples thereof include the same monovalent hydrocarbon groups having 1 to 50 carbon atoms as those described above for E. In the above formula (11a), Y 1’ is a divalent hydrocarbon group having 1 to 18 carbon atoms, which may have one or more bonds selected from silicon atoms and siloxane bonds, and examples thereof include those shown below. In the following structure, the bond on the left side is A, B 1 , E 1’ and the bond on the right side is preferably bonded to a vinyl group. (In the formula, g1, j1, and k1 are the same as above, f1' is an integer of 0 to 8, h1' is an integer of 0 to 6, and the sum of g1 and h1' is an integer of 2 to 8.)

[0110] Examples of the compound represented by formula (11a) include the compounds shown below. (In the formula, a1 and f1′ are each independently the same as above.)

[0111] Examples of compounds having a SiH group and a hydrolyzable silyl group include trimethoxysilane, triethoxysilane, triacetoxysilane, and trichlorosilane.

[0112] In Preparation Method 1, the amount of the compound having a SiH group and a hydrolyzable silyl group used is preferably 1 to 6 moles, particularly 1.5 to 4 moles, per mole of alkenyl group in the hydrocarbon terminal group-containing compound having an alkenyl group at the terminal.

[0113] Furthermore, examples of hydrocarbon terminal group-containing compounds having SiH groups at their terminals include compounds represented by the following formula (11b): (In the formula, A, B 1 , E 1’ is the same as above, and Y 1" is a divalent hydrocarbon group having a silicon atom or a siloxane bond.

[0114] In the above formula (11b), Y 1" is a divalent hydrocarbon group having a silicon atom or a siloxane bond, and examples thereof include the following: In the following structure, it is preferable that the bond on the left side is bonded to a carbon atom, and the bond on the right side is bonded to a hydrogen atom. (wherein f1 and k1 are the same as above.)

[0115] Examples of the compound represented by formula (11b) include the compounds shown below. (In the formula, a1 and f1 are each independently the same as above.)

[0116] Examples of compounds having an alkenyl group and a hydrolyzable silyl group include vinyltrimethoxysilane, allyltrimethoxysilane, and octenyltrimethoxysilane.

[0117] In Preparation Method 2, the amount of the compound having an alkenyl group and a hydrolyzable silyl group used is preferably 1 to 5 moles, particularly 1 to 3 moles, per mole of SiH group in the hydrocarbon terminal group-containing compound having an SiH group at the terminal.

[0118] In Preparation Methods 1 and 2, examples of the hydrosilylation catalyst include platinum black, chloroplatinic acid, alcohol-modified chloroplatinic acid, complexes of chloroplatinic acid with olefins, aldehydes, vinylsiloxanes, acetylene alcohols, and the like, and platinum group metal catalysts such as tetrakis(triphenylphosphine)palladium and chlorotris(triphenylphosphine)rhodium. Platinum compounds such as vinylsiloxane coordination compounds are preferred. The platinum compounds are preferably used by dissolving them in a solvent such as toluene, a lower alcohol, a higher alcohol, or a silicone-based solvent. The amount of the hydrosilylation catalyst used is preferably 0.001 to 1,000 ppm, and more preferably 0.01 to 100 ppm, in terms of transition metal (mass), relative to the mass of the hydrocarbon terminal group-containing compound having an alkenyl group or SiH group at the terminal.

[0119] In Preparation Methods 1 and 2, a solvent can be used during the reaction. Examples of the solvent include aromatic hydrocarbons such as toluene and xylene, aliphatic or alicyclic hydrocarbons such as n-pentane, n-hexane, and cyclohexane, cyclic ether compounds such as tetrahydrofuran and dioxane, and ketones such as acetone and methyl ethyl ketone. The amount of the solvent used is preferably 0 to 1,000 parts by mass, and more preferably 50 to 200 parts by mass, per 100 parts by mass of the hydrocarbon terminal group-containing compound having an alkenyl group or a SiH group at the terminal.

[0120] In Preparation Methods 1 and 2, the reaction conditions for the hydrocarbon terminal group-containing compound having an alkenyl group at the terminal with the compound having a SiH group and a hydrolyzable silyl group, and the reaction conditions for the hydrocarbon terminal group-containing compound having a SiH group at the terminal with the compound having an alkenyl group and a hydrolyzable silyl group are preferably a temperature of 20 to 120°C, particularly 60 to 100°C, for 0.5 to 72 hours, particularly 1 to 36 hours.

[0121] In the compound represented by the above formula (12), E 1 is a monovalent hydrocarbon group having 1 to 50 carbon atoms, for example, by the following method: A hydrocarbon terminal group-containing compound having an alkenyl group at the terminal is mixed with trichlorosilane, the mixture is reacted in the presence of a hydrosilylation catalyst, and the resulting compound is then reacted with ammonia gas.

[0122] Here, the reaction product of the hydrocarbon terminal group-containing compound having an alkenyl group at the end and trichlorosilane can be prepared in the same manner as in Preparation Method 1 described above.

[0123] In the method for preparing the compound represented by formula (12), the amount of ammonia gas used is preferably 1 to 300 cc / min, particularly preferably 30 to 200 cc / min.

[0124] In the method for preparing the compound represented by formula (12), the reaction conditions for the reaction of ammonia gas with a reactant of a hydrocarbon terminal group-containing compound having an alkenyl group at the terminal and trichlorosilane are preferably room temperature (23±15°C, the same applies hereinafter), particularly a temperature of 20 to 30°C, for 2 to 36 hours, particularly 4 to 12 hours.

[0125] If necessary, a hydrolysis and condensation catalyst such as an organotin compound (dibutyltin dimethoxide, dibutyltin dilaurate, etc.), an organotitanium compound (tetra-n-butyl titanate, etc.), an organic acid (acetic acid, methanesulfonic acid, fluorine-modified carboxylic acid, etc.), or an inorganic acid (hydrochloric acid, sulfuric acid, etc.) may be added to the surface treatment agent containing the fluorine-free alkyl group-containing compound having a hydrolyzable silyl group and / or its partial hydrolysis and condensation product. Of these, acetic acid, tetra-n-butyl titanate, dibutyltin dilaurate, etc. are particularly desirable. The amount added is a catalytic amount, and is typically 0.01 to 5 parts by mass, particularly 0.1 to 1 part by mass, per 100 parts by mass of the fluorine-free alkyl group-containing compound having a hydrolyzable silyl group and / or its partial hydrolysis and condensation product.

[0126] Furthermore, the surface treatment agent containing the fluorine-free alkyl group-containing compound having a hydrolyzable silyl group and / or its partial hydrolysis condensate may contain a solvent. The solvent is preferably a hydrocarbon solvent (petroleum benzine, mineral spirits, toluene, xylene, etc.), a ketone solvent (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.), an alcohol solvent (ethanol, 1-propanol, 2-propanol, butanol, etc.), or an ether solvent (tetrahydrofuran (THF), monoethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, dioxane, etc.).

[0127] Two or more of the above solvents may be mixed, and it is preferable to uniformly dissolve the fluorine-free alkyl group-containing compound having a hydrolyzable silyl group and / or its partial hydrolysis condensate. The optimal concentration of the fluorine-free alkyl group-containing compound having a hydrolyzable silyl group and / or its partial hydrolysis condensate to be dissolved in the solvent is not limited and may be appropriately selected depending on the method of use of the surface treatment agent. The concentration is usually 0.01 to 30 mass%, preferably 0.02 to 25 mass%, and more preferably 0.05 to 20 mass%.

[0128] The water-repellent surface layer can be formed by wet or dry coating a surface treatment agent containing a reactive silyl compound exhibiting surface water repellency (a surface treatment agent containing the above-mentioned fluoropolyether group-containing polymer having a silanol group or a hydrolyzable silyl group and / or a partial (hydrolyzed) condensate thereof, or a surface treatment agent containing the above-mentioned alkyl group-containing compound having a hydrolyzable silyl group and not containing a fluorine atom and / or a partial hydrolyzed condensate thereof) on the outer surface of the primer layer formed as described above, followed by drying to remove the solvent from the surface treatment agent and curing the reactive silyl compound (a fluoropolyether group-containing polymer having a silanol group or a hydrolyzable silyl group and / or a partial (hydrolyzed) condensate thereof or a fluoropolyether group-containing polymer composition, or a fluorine atom-free alkyl group-containing compound having a hydrolyzable silyl group and / or a partial hydrolyzed condensate thereof).

[0129] The water-repellent surface layer can be formed using a surface treatment agent by a wet coating method such as brush coating, dip coating, or spray coating, or by a dry coating method such as vapor deposition (physical vapor deposition (PVD) or chemical vapor deposition (CVD)).

[0130] After applying the surface treatment agent, the solvent is dried and removed, and curing treatment is carried out. In the case of a wet coating method, the curing treatment can be carried out at 60 to 150°C, preferably 60 to 120°C, and a relative humidity of 95% or less for 30 minutes to 24 hours, preferably 30 minutes to 2 hours. In the case of a dry coating method, the curing treatment can be carried out at 25 to 150°C, preferably 25 to 80°C, and a relative humidity of 95% or less for 30 minutes to 48 hours, preferably 30 minutes to 24 hours.

[0131] The thickness of the water-repellent surface layer is 0.5 to 20 nm, preferably 1 to 15 nm. If the thickness of the water-repellent surface layer is less than 0.5 nm, the water repellency may be reduced due to the influence of the properties of the primer layer, while if it exceeds 20 nm, changes in appearance such as color may occur due to differences in the refractive index between the substrate or primer layer and the water-repellent surface layer. In the present invention, the thickness can be measured by X-ray reflectance measurement, spectroscopic ellipsometry measurement, or the like.

[0132] By forming a primer layer on the surface of a substrate using the aqueous primer composition of the present invention, a cured product of a reactive silyl compound exhibiting surface water repellency firmly adheres to the substrate surface, allowing the production of a water-repellent article having a water-repellent surface layer with excellent abrasion resistance and chemical resistance. Furthermore, the method for producing the water-repellent article does not require a vacuum process or a high-temperature heating process, and the article can be formed using only a wet process or a wet and dry process. For these reasons, the water-repellent article of the present invention can be used in a variety of applications, such as housings, frames, floors, touch panels, windows, lenses, display covers, protective films, etc. for mobile electronic devices, household appliances, automobiles, outdoor equipment, building materials, housing facilities, eyeglasses, etc.

[0133] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to the following examples. In the following examples, the number average molecular weight is 19 This is a value calculated from the characteristic peak intensity ratio of F-NMR analysis.

[0134] [Comparative Example 1] [Alkaline cleaning of glass substrate] A soda-lime glass substrate (size: 100 mm × 50 mm × 0.7 mm (thickness)) was immersed in an alkaline cleaning solution (an aqueous solution prepared by diluting Semiclean L.G.L manufactured by Yokohama Oil & Fat Industries Co., Ltd. to 5% by mass) and subjected to ultrasonic cleaning for 5 minutes. Thereafter, the substrate was immersed in ion-exchanged water and subjected to ultrasonic cleaning for 6 minutes. The moisture in the glass substrate was blown off with compressed air and the substrate was dried.

[0135] [Plasma Cleaning of Glass Substrate] The surface of the glass substrate that had been subjected to the above alkaline cleaning was treated with oxygen-argon mixed plasma. The treatment conditions are as follows: Treatment device: PDC510 (manufactured by Yamato Scientific Co., Ltd.) Oxygen gas flow rate: 10 sccm (Standard Cubic Centimeters) Argon gas flow rate: 100 sccm Treatment pressure: 60 Pa RF power supply: 250 W Treatment time: 30 seconds

[0136] [Formation of Primer Layer] A glass substrate that had been subjected to alkali cleaning and plasma cleaning was dip-coated with the aqueous primer composition 1 shown below, followed by heating and drying to form a primer layer with a thickness of 4 nm. The dip-coating and heating conditions were as follows: Immersion time: 30 seconds, Pull-up speed: 0.5 mm / second, Heating conditions: 150°C, 30 minutes. The thickness of the primer layer was measured by X-ray reflectance measurement.

[0137] [Water-based primer composition 1] 10 g of water-dispersed silica nanoparticles (Snowtex ST-XS, manufactured by Nissan Chemical Industries, Ltd.) and 1,990 g of pure water were uniformly mixed to obtain a pure water dispersion of silica nanoparticles with an average particle size of 7 nm (silica nanoparticle concentration: 0.1% by mass, pH 9), which was designated as water-based primer composition 1.

[0138] [Preparation of Surface Treatment Agent I] Compound (A) (number average molecular weight: 4000) represented by the following formula was dissolved in a fluorine-based solvent (NOVEC HFE-7200, ethyl perfluorobutyl ether, manufactured by 3M Company) to a concentration of 20 mass %, thereby obtaining surface treatment agent I. (p / q=1.0, p+q=42)

[0139] [Formation of a water-repellent surface layer by physical vapor deposition (PVD)] The glass substrate with the primer layer was set in a resistance heating vacuum deposition apparatus (VTR-350M, manufactured by ULVAC KIKO Co., Ltd.), 5 μL of surface treatment agent I was dropped onto the resistance heating section, and the pressure was reduced. -3 Once the pressure was reduced to 0.1 Pa or less, resistance heating was initiated. The power input to the resistance heating was adjusted so that the maximum evaporation rate measured by a quartz crystal film thickness meter installed approximately 20 cm away from the resistance heating unit was 1.0 nm / sec. Resistance heating was continued for 100 seconds after the evaporation rate measured by the quartz crystal film thickness meter decreased to 0.1 nm / sec. The device was allowed to cool for 5 minutes, after which it was opened to the atmosphere to obtain a glass substrate coated with surface treatment agent I. The glass substrate coated with the surface treatment agent I was left in an environment of 25°C and 50% relative humidity for 24 hours to cure and fix the surface treatment agent I, thereby obtaining a glass substrate having a water-repellent surface layer of 10 nm thick made of a fluoropolyether group-containing polymer. The thickness of the water-repellent surface layer was calculated using a calibration curve by quantifying the fluorescent X-ray intensity derived from elemental fluorine using a fluorescent X-ray analyzer (manufactured by Rigaku Corporation, product name: Fluorescent X-ray analyzer Primini).

[0140] Comparative Example 2 A glass substrate having a water-repellent surface layer was obtained in the same manner as in Comparative Example 1, except that the primer layer was a 10 nm-thick SiO layer formed by electron beam evaporation. The thicknesses of the primer layer and the water-repellent surface layer are shown in Table 1.

[0141] Example 1 A glass substrate having a water-repellent surface layer was obtained in the same manner as in Comparative Example 1, except that the following aqueous primer composition 2 was used. The film thicknesses of the primer layer and the water-repellent surface layer are shown in Table 1.

[0142] [Water-based Primer Composition 2] 10 g of water-dispersed silica nanoparticles (Snowtex ST-XS, manufactured by Nissan Chemical Industries, Ltd.), 10 g of an aqueous solution of ammonium zirconium carbonate (Baycoat 20, manufactured by Nippon Light Metal Co., Ltd.), and 1,980 g of pure water were uniformly mixed to obtain a pure water dispersion of silica nanoparticles with an average particle size of 7 nm and ammonium zirconium carbonate (silica nanoparticle concentration: 0.1% by mass, zirconium oxide equivalent concentration: 0.1% by mass, pH 9), which was designated as Water-based Primer Composition 2. The zirconium oxide equivalent concentration was determined by chelate titration. That is, an excess amount of ethylenediaminetetraacetic acid (EDTA) was added to an aqueous solution of ammonium zirconium carbonate treated with perchloric acid and nitric acid, and the solution was heated to form a zirconium-EDTA complex salt. The pH of the solution was adjusted to 5-6, and the excess EDTA was titrated using a lead standard solution to determine the zirconium oxide concentration (the same applies hereinafter).

[0143] Example 2 A glass substrate having a water-repellent surface layer was obtained in the same manner as in Comparative Example 1, except that the following aqueous primer composition 3 was used. The film thicknesses of the primer layer and the water-repellent surface layer are shown in Table 1.

[0144] [Water-based primer composition 3] 10 g of water-dispersed silica nanoparticles (Snowtex ST-XS, manufactured by Nissan Chemical Industries, Ltd.), 32.3 g of niobium oxide nanoparticles (Baylal Nb-G6000, manufactured by Taki Chemical Industries, Ltd.), and 1,957.7 g of pure water were uniformly mixed to obtain a pure water dispersion of silica nanoparticles with an average particle size of 7 nm and niobium oxide nanoparticles with an average particle size of 6 nm (silica nanoparticle concentration: 0.1 mass%, niobium oxide nanoparticle concentration 0.1 mass%, pH 9), which was designated as water-based primer composition 3.

[0145] Example 3 A glass substrate having a water-repellent surface layer was obtained in the same manner as in Comparative Example 1, except that the following aqueous primer composition 4 was used. The film thicknesses of the primer layer and the water-repellent surface layer are shown in Table 1.

[0146] [Water-based primer composition 4] 10 g of water-dispersed silica nanoparticles (Snowtex ST-XS, manufactured by Nissan Chemical Industries, Ltd.), 25 g of an aqueous solution of ammonium zirconium carbonate (Baycoat 20, manufactured by Nippon Light Metal Co., Ltd.), and 1,965 g of pure water were uniformly mixed to obtain a pure water dispersion of silica nanoparticles with an average particle size of 7 nm and ammonium zirconium carbonate (silica nanoparticle concentration: 0.1% by mass, zirconium oxide equivalent concentration: 0.25% by mass, pH 9), which was designated as water-based primer composition 4.

[0147] Example 4 A glass substrate having a water-repellent surface layer was obtained in the same manner as in Comparative Example 1, except that the following aqueous primer composition 5 was used. The film thicknesses of the primer layer and the water-repellent surface layer are shown in Table 1.

[0148] [Water-based primer composition 5] 10 g of water-dispersed silica nanoparticles (Snowtex ST-XS, manufactured by Nissan Chemical Industries, Ltd.), 50 g of an aqueous solution of ammonium zirconium carbonate (Baycoat 20, manufactured by Nippon Light Metal Co., Ltd.), and 1,940 g of pure water were uniformly mixed to obtain a pure water dispersion of silica nanoparticles with an average particle size of 7 nm and ammonium zirconium carbonate (silica nanoparticle concentration: 0.1% by mass, zirconium oxide equivalent concentration: 0.5% by mass, pH 9), which was designated as water-based primer composition 5.

[0149] Comparative Example 3 A glass substrate having a water-repellent surface layer was obtained in the same manner as in Comparative Example 1, except that the following aqueous primer composition 6 was used. The film thicknesses of the primer layer and the water-repellent surface layer are shown in Table 1.

[0150] [Water-based primer composition 6] 10 g of water-dispersed silica nanoparticles (Snowtex ST-XS, manufactured by Nissan Chemical Industries, Ltd.), 100 g of an aqueous solution of ammonium zirconium carbonate (Baycoat 20, manufactured by Nippon Light Metal Co., Ltd.), and 1,890 g of pure water were uniformly mixed to obtain a pure water dispersion of silica nanoparticles with an average particle size of 7 nm and ammonium zirconium carbonate (silica nanoparticle concentration: 0.1% by mass, zirconium oxide equivalent concentration: 1.0% by mass, pH 9), which was designated as water-based primer composition 6.

[0151] The glass substrates having the water-repellent surface layers obtained in the above Examples and Comparative Examples were evaluated for initial water contact angle, steel wool abrasion resistance, and alkali resistance by the methods described below.

[0152] [Measurement of initial water contact angle] The water contact angle of the water-repellent surface layer of the glass substrate was measured by the sessile drop method using a 2 μL droplet and θ / 2 analysis method using a contact angle meter Drop Master (manufactured by Kyowa Interface Science Co., Ltd.) in accordance with JIS R 3257: 1999. The measurement results are shown in Table 1.

[0153] [Steel Wool Abrasion Durability Test] The water-repellent surface layer of the glass substrate was tested using a reciprocating abrasion tester (Type 40, manufactured by Shinto Scientific Co., Ltd.) under the following conditions: Abrasive: Steel wool #0000 (Bonstar) Load: 1 kgf Reciprocating distance: 40 mm Reciprocating speed: 60 reciprocations per minute Total number of reciprocating friction cycles: 15,000 The water contact angle of the friction-wear portion was measured every 2,500 reciprocating friction cycles using the same method as above. The number of reciprocating friction cycles at which a water contact angle of 90° or more was maintained was taken as the steel wool abrasion durability cycle. In Comparative Example 1, the steel wool abrasion durability cycle was 15,000 cycles. The steel wool abrasion durability cycle is shown in Table 1, where Comparative Example 1 is set to 100, and the ratio of the steel wool abrasion durability cycles of each Example and Comparative Example to the steel wool abrasion durability cycle of Comparative Example 1 is taken as the steel wool abrasion durability cycle.

[0154] [Alkali Resistance Test] A glass substrate having a water-repellent surface layer was immersed in a 0.4% by mass sodium hydroxide aqueous solution (test liquid) at 55°C. Every two hours, the glass substrate was removed from the test liquid. Pure water was poured onto the water-repellent surface layer of the glass substrate for one minute to remove the test liquid, and the surface moisture was removed by blowing dry air. The water contact angle of the water-repellent surface layer of the glass substrate was then measured in the same manner as above. Immersion in the test liquid was repeated until the water contact angle fell below 90°, and the immersion time during which the water contact angle of 90° was maintained was defined as the alkali resistance time. In Comparative Example 1, the alkali resistance time was 16 hours. The alkali resistance is shown in Table 1, where Comparative Example 1 is set to 100, and the ratio of the alkali resistance time of each Example and Comparative Example to the alkali resistance time of Comparative Example 1.

[0155]

[0156] Comparative Example 4 Alkaline Cleaning of Stainless Steel Substrate A stainless steel substrate (bright annealed (BA) treated SUS304, size: 100 mm × 50 mm × 1.0 mm (thickness)) was immersed in an alkaline cleaning solution (aqueous solution prepared by diluting Semiclean L.G.L manufactured by Yokohama Oil & Fat Industries Co., Ltd. to 5% by mass) and subjected to ultrasonic cleaning for 5 minutes. Thereafter, the substrate was immersed in ion-exchanged water and subjected to ultrasonic cleaning for 6 minutes. The water content of the stainless steel substrate was blown off with compressed air and the substrate was dried.

[0157] [Plasma Cleaning of Stainless Steel Substrate] The surface of the stainless steel substrate that had been subjected to the alkaline cleaning described above was treated with oxygen-argon mixed plasma. The treatment conditions are as follows: Treatment device: PDC510 (manufactured by Yamato Scientific Co., Ltd.) Oxygen gas flow rate: 10 sccm (Standard Cubic Centimeters) Argon gas flow rate: 100 sccm Treatment pressure: 60 Pa RF power supply: 250 W Treatment time: 30 seconds

[0158] [Formation of Primer Layer] The above aqueous primer composition 1 was dip-coated on a stainless steel substrate that had been subjected to alkali cleaning and plasma cleaning, and then the substrate was heated and dried to form a primer layer with a thickness of 4 nm. The dip-coating and heating conditions were the same as those in Comparative Example 1. The thickness of the primer layer was measured by X-ray reflectivity measurement.

[0159] [Formation of a Water-Repellent Surface Layer by Physical Vapor Deposition (PVD)] The above-described stainless steel substrate with a primer layer was placed in a resistance heating vacuum deposition apparatus (VTR-350M, manufactured by ULVAC KIKO, Inc.), and the same treatment as in Comparative Example 1 was carried out using the above-described surface treatment agent I, to obtain a stainless steel substrate coated with the surface treatment agent I. The stainless steel substrate coated with the above-described surface treatment agent I was left in an environment of 25°C and 50% relative humidity for 24 hours, to cure and fix the surface treatment agent I, thereby obtaining a stainless steel substrate having a water-repellent surface layer of 4 nm thick made of a fluoropolyether group-containing polymer. The thickness of the above-described water-repellent surface layer was calculated using a calibration curve by quantifying the intensity of fluorescent X-rays derived from elemental fluorine using a fluorescent X-ray analyzer (manufactured by Rigaku Corporation, product name: fluorescent X-ray analyzer Primini).

[0160] Comparative Example 5 A stainless steel substrate having a water-repellent surface layer was obtained in the same manner as in Comparative Example 4, except that the primer layer was a 10 nm-thick SiO layer formed by electron beam evaporation. The thicknesses of the primer layer and the water-repellent surface layer are shown in Table 2.

[0161] Example 5 A stainless steel substrate having a water-repellent surface layer was obtained in the same manner as in Comparative Example 4, except that the above-mentioned aqueous primer composition 2 was used. The film thicknesses of the primer layer and the water-repellent surface layer are shown in Table 2.

[0162] Example 6 A stainless steel substrate having a water-repellent surface layer was obtained in the same manner as in Comparative Example 4, except that the above-mentioned aqueous primer composition 3 was used. The film thicknesses of the primer layer and the water-repellent surface layer are shown in Table 2.

[0163] Example 7 A stainless steel substrate having a water-repellent surface layer was obtained in the same manner as in Comparative Example 4, except that the following aqueous primer composition 7 was used. The film thicknesses of the primer layer and the water-repellent surface layer are shown in Table 2.

[0164] [Water-based primer composition 7] 10 g of water-dispersed silica nanoparticles (Snowtex ST-XS, manufactured by Nissan Chemical Industries, Ltd.), 75 g of an aqueous solution of ammonium zirconium carbonate (Baycoat 20, manufactured by Nippon Light Metal Co., Ltd.), and 1,915 g of pure water were uniformly mixed to obtain a pure water dispersion of silica nanoparticles with an average particle size of 7 nm and ammonium zirconium carbonate (silica nanoparticle concentration: 0.1% by mass, zirconium oxide equivalent concentration: 0.75% by mass, pH 9), which was designated as Water-based primer composition 7.

[0165] Comparative Example 6 A stainless steel substrate having a water-repellent surface layer was obtained in the same manner as in Comparative Example 4, except that the above-mentioned aqueous primer composition 6 was used. The film thicknesses of the primer layer and the water-repellent surface layer are shown in Table 2.

[0166] The stainless steel substrates having the water-repellent surface layers obtained in the above Examples and Comparative Examples were evaluated for initial water contact angle, nonwoven fabric abrasion resistance, and alkali resistance by the methods described below.

[0167] [Measurement of initial water contact angle] The water contact angle of the water-repellent surface layer of the stainless steel substrate was measured by the sessile drop method using a 2 μL droplet and an analysis method of θ / 2 using a contact angle meter Drop Master (manufactured by Kyowa Interface Science Co., Ltd.) in accordance with JIS R 3257: 1999. The measurement results are shown in Table 2.

[0168] [Nonwoven Fabric Abrasion Durability Test] The water-repellent surface layer of the stainless steel substrate was tested using a reciprocating abrasion tester (Type 40, manufactured by Shinto Scientific Co., Ltd.) under the following conditions: Abrasive: Bemcot (M-3II, manufactured by Ozu Sangyo Co., Ltd.) Load: 1 kgf Reciprocating distance: 40 mm Reciprocating speed: 40 reciprocations per minute Total number of reciprocating friction cycles: 10,000 cycles The water contact angle of the friction-wear portion was measured every 2,500 reciprocating friction cycles using the same method as above. The number of reciprocating abrasion cycles at which a water contact angle of 90° or more was maintained was taken as the nonwoven fabric abrasion durability cycle. In Comparative Example 4, the nonwoven fabric abrasion durability cycle was 10,000 cycles. The ratio of the number of reciprocating abrasion cycles of the nonwoven fabric of each Example and Comparative Example to the number of reciprocating abrasion cycles of the nonwoven fabric of Comparative Example 4, which is set to 100, is shown in Table 2 as the nonwoven fabric abrasion durability.

[0169] [Alkali Resistance Test] A stainless steel substrate having a water-repellent surface layer was immersed in a 0.4% by mass aqueous sodium hydroxide solution (test liquid) at 55°C. Every two hours, the substrate was removed from the test liquid. Pure water was poured over the water-repellent surface layer of the stainless steel substrate for one minute to remove the test liquid, and the surface moisture was removed by blowing dry air onto the substrate. The water contact angle of the water-repellent surface layer of the stainless steel substrate was then measured in the same manner as above. Immersion in the test liquid was repeated until the water contact angle fell below 90°, and the immersion time during which the water contact angle of 90° was maintained was defined as the alkali resistance time. In Comparative Example 4, the alkali resistance time was 8 hours. The alkali resistance is shown in Table 2, where Comparative Example 4 is set to 100, and the ratio of the alkali resistance time of each Example and Comparative Example to the alkali resistance time of Comparative Example 4.

[0170]

[0171] Comparing the results of Comparative Example 1 and Examples 1 to 4, Examples 1 to 4 exhibited excellent chemical resistance and good steel wool abrasion resistance. On the other hand, comparing the results of Comparative Example 4 and Examples 5 to 7, Examples 5 to 7 all exhibited excellent chemical resistance and water-repellent surface layers with excellent nonwoven fabric abrasion resistance. Furthermore, Comparative Examples 2 and 5, which used a SiO2 primer layer, exhibited inferior chemical resistance compared to the corresponding Examples and other Comparative Examples. Furthermore, Comparative Examples 3 and 6, which used Primer Composition 6, had a metal compound to silica nanoparticle ratio of 1000%, and therefore exhibited superior chemical resistance compared to Comparative Examples 1 and 4, but did not exhibit good abrasion resistance with either steel wool or nonwoven fabric.

[0172] [Comparative Example 7] [Alkaline cleaning of glass substrate] A soda-lime glass substrate (size: 100 mm × 50 mm × 0.7 mm (thickness)) was immersed in an alkaline cleaning solution (an aqueous solution prepared by diluting Semiclean L.G.L manufactured by Yokohama Oil & Fat Industries Co., Ltd. to 5% by mass) and subjected to ultrasonic cleaning for 5 minutes. Thereafter, the substrate was immersed in ion-exchanged water and subjected to ultrasonic cleaning for 6 minutes. The moisture in the glass substrate was blown off with compressed air, and the substrate was dried.

[0173] [Plasma Cleaning of Glass Substrate] The surface of the glass substrate that had been subjected to the above alkaline cleaning was treated with oxygen-argon mixed plasma. The treatment conditions are as follows: Treatment device: PDC510 (manufactured by Yamato Scientific Co., Ltd.) Oxygen gas flow rate: 10 sccm (Standard Cubic Centimeters) Argon gas flow rate: 100 sccm Treatment pressure: 60 Pa RF power supply: 250 W Treatment time: 30 seconds

[0174] [Formation of Primer Layer] The above aqueous primer composition 1 was dip-coated on a glass substrate that had been subjected to alkali cleaning and plasma cleaning, and then heated and dried to form a primer layer with a thickness of 4 nm. The dip-coating and heating conditions are as follows: Immersion time: 30 seconds, Pull-up speed: 0.5 mm / second, Heating conditions: 150°C, 30 minutes. The thickness of the primer layer was measured by X-ray reflectivity measurement.

[0175] [Preparation of Surface Treatment Agent II] A reaction vessel was charged with a compound represented by the following formula (b): 1.00 g (1.82 × 10 -3 mol), toluene 1.00 g, trimethoxysilane 0.667 g (5.46 × 10 -3 mol), and a toluene solution of chloroplatinic acid / vinylsiloxane complex 6.62 × 10 -3 g (2.05 x 10 as Pt alone) -8 The resulting mixture was aged at 80° C. for 24 hours. Thereafter, the solvent and unreacted materials were distilled off under reduced pressure to obtain a compound. The obtained compound was 1 H-NMR confirmed that the compound had the structure shown in formula (B) below. The compound represented by the above formula (B) was dissolved in propylene glycol monomethyl ether (PGME) to a concentration of 20% by mass, to give a surface treatment agent II.

[0176] [Formation of a water-repellent surface layer by physical vapor deposition (PVD)] The glass substrate with the primer layer was set in a resistance heating type vacuum deposition apparatus (VTR-350M, manufactured by ULVAC KIKO Co., Ltd.), 3 μL of surface treatment agent II was dropped onto the resistance heating section, and the pressure was reduced. -3 Once the pressure was reduced to 0.1 Pa or less, resistance heating was initiated. The power input to the resistance heating was adjusted so that the maximum evaporation rate measured by a quartz crystal film thickness meter installed approximately 20 cm away from the resistance heating unit was 1.0 nm / sec. Resistance heating was continued for 100 seconds after the evaporation rate measured by the quartz crystal film thickness meter decreased to 0.1 nm / sec. The device was allowed to cool for 5 minutes, after which it was opened to the atmosphere, yielding a glass substrate coated with surface treatment agent II. The glass substrate coated with surface treatment agent II was left in an environment of 80°C and 80% relative humidity for 4 hours to cure and fix the surface treatment agent II, yielding a glass substrate having a 4 nm-thick water-repellent surface layer made of an alkyl group-containing compound not containing fluorine atoms. The thickness of the water-repellent surface layer was calculated using a spectroscopic ellipsometer (manufactured by J.A. Woolam, product name: M-2000D).

[0177] Comparative Example 8 A glass substrate having a water-repellent surface layer was obtained in the same manner as in Comparative Example 7, except that the primer layer was a SiO layer having a thickness of 10 nm formed by electron beam evaporation. The thicknesses of the primer layer and the water-repellent surface layer are shown in Table 3.

[0178] Example 8 A glass substrate having a water-repellent surface layer was obtained in the same manner as in Comparative Example 7, except that the above-mentioned aqueous primer composition 2 was used. The film thicknesses of the primer layer and the water-repellent surface layer are shown in Table 3.

[0179] Example 9 A glass substrate having a water-repellent surface layer was obtained in the same manner as in Comparative Example 7, except that the above-mentioned aqueous primer composition 3 was used. The film thicknesses of the primer layer and the water-repellent surface layer are shown in Table 3.

[0180] Example 10 A glass substrate having a water-repellent surface layer was obtained in the same manner as in Comparative Example 7, except that the above-mentioned aqueous primer composition 7 was used. The film thicknesses of the primer layer and the water-repellent surface layer are shown in Table 3.

[0181] Comparative Example 9 A glass substrate having a water-repellent surface layer was obtained in the same manner as in Comparative Example 7, except that the above-mentioned aqueous primer composition 6 was used. The film thicknesses of the primer layer and the water-repellent surface layer are shown in Table 3.

[0182] The glass substrates having the water-repellent surface layers obtained in the above Examples and Comparative Examples were evaluated for initial water contact angle, steel wool abrasion resistance, and alkali resistance by the methods described below.

[0183] [Measurement of initial water contact angle] The water contact angle of the water-repellent surface layer of the glass substrate was measured by the sessile drop method using a 2 μL droplet and θ / 2 analysis method using a contact angle meter Drop Master (manufactured by Kyowa Interface Science Co., Ltd.) in accordance with JIS R 3257: 1999. The measurement results are shown in Table 3.

[0184] [Steel Wool Abrasion Durability Test] The water-repellent surface layer of the glass substrate was tested using a reciprocating abrasion tester (Type 40, manufactured by Shinto Scientific Co., Ltd.) under the following conditions: Abrasive: Steel wool #0000 (Bonstar) Load: 0.5 kgf Reciprocating distance: 40 mm Reciprocating speed: 60 reciprocations per minute Total number of reciprocating friction cycles: 4,000 cycles The water contact angle of the friction-wear portion was measured every 500 reciprocating friction cycles using the same method as above. The number of reciprocating friction cycles at which a water contact angle of 90° or more was maintained was taken as the steel wool abrasion durability cycle. In Comparative Example 7, the steel wool abrasion durability cycle was 4,000 cycles. Table 3 shows the steel wool abrasion durability as the ratio of the steel wool abrasion durability cycles of each Example and Comparative Example to the steel wool abrasion durability cycle of Comparative Example 7, where Comparative Example 7 is set to 100.

[0185] [Alkali Resistance Test] A glass substrate having a water-repellent surface layer was immersed in a 0.4% by mass sodium hydroxide aqueous solution (test liquid) at 55°C. Every two hours, the glass substrate was removed from the test liquid. Pure water was poured onto the water-repellent surface layer of the glass substrate for one minute to remove the test liquid, and the surface moisture was removed by blowing dry air. The water contact angle of the water-repellent surface layer of the glass substrate was then measured in the same manner as above. Immersion in the test liquid was repeated until the water contact angle fell below 90°, and the immersion time during which the water contact angle of 90° was maintained was defined as the alkali resistance time. In Comparative Example 7, the alkali resistance time was 8 hours. The alkali resistance is shown in Table 3, where Comparative Example 7 is set to 100, and the ratio of the alkali resistance time of each Example and Comparative Example to the alkali resistance time of Comparative Example 7.

[0186]

[0187] Comparative Example 10 Alkaline Cleaning of Stainless Steel Substrate A stainless steel substrate (bright annealed (BA) treated SUS304, size: 100 mm × 50 mm × 1.0 mm (thickness)) was immersed in an alkaline cleaning solution (aqueous solution prepared by diluting Semiclean L.G.L manufactured by Yokohama Oil & Fat Industries Co., Ltd. to 5% by mass) and subjected to ultrasonic cleaning for 5 minutes. Thereafter, the substrate was immersed in ion-exchanged water and subjected to ultrasonic cleaning for 6 minutes. The water content of the stainless steel substrate was blown off with compressed air and the substrate was dried.

[0188] [Plasma Cleaning of Stainless Steel Substrate] The surface of the stainless steel substrate that had been subjected to the alkaline cleaning described above was treated with oxygen-argon mixed plasma. The treatment conditions are as follows: Treatment device: PDC510 (manufactured by Yamato Scientific Co., Ltd.) Oxygen gas flow rate: 10 sccm (Standard Cubic Centimeters) Argon gas flow rate: 100 sccm Treatment pressure: 60 Pa RF power supply: 250 W Treatment time: 30 seconds

[0189] [Formation of Primer Layer] The above aqueous primer composition 1 was dip-coated on a stainless steel substrate that had been subjected to alkali cleaning and plasma cleaning, and then the substrate was heated and dried to form a primer layer with a thickness of 4 nm. The dip-coating and heating conditions were the same as those in Comparative Example 1. The thickness of the primer layer was measured by X-ray reflectivity measurement.

[0190] [Formation of a Water-Repellent Surface Layer by Physical Vapor Deposition (PVD)] The above-described stainless steel substrate with a primer layer was placed in a resistance heating vacuum deposition apparatus (VTR-350M, manufactured by ULVAC KIKO, Inc.), and the same treatment as in Comparative Example 7 was carried out using the above-described surface treatment agent II, yielding a stainless steel substrate coated with surface treatment agent II. The stainless steel substrate coated with the above-described surface treatment agent II was left in an environment of 80°C and 80% relative humidity for 4 hours, allowing the surface treatment agent II to harden and set, yielding a stainless steel substrate with a 4 nm-thick water-repellent surface layer made of an alkyl group-containing compound that does not contain fluorine atoms. The thickness of the above-described water-repellent surface layer was calculated using a spectroscopic ellipsometer (manufactured by J.A. Woolam, product name: M-2000D).

[0191] Comparative Example 11 A stainless steel substrate having a water-repellent surface layer was obtained in the same manner as in Comparative Example 10, except that the primer layer was a 10 nm-thick SiO layer formed by electron beam evaporation. The thicknesses of the primer layer and the water-repellent surface layer are shown in Table 4.

[0192] Example 11 A stainless steel substrate having a water-repellent surface layer was obtained in the same manner as in Comparative Example 10, except that the above-mentioned aqueous primer composition 2 was used. The film thicknesses of the primer layer and the water-repellent surface layer are shown in Table 4.

[0193] Example 12 A stainless steel substrate having a water-repellent surface layer was obtained in the same manner as in Comparative Example 10, except that the aqueous primer composition 3 was used. The film thicknesses of the primer layer and the water-repellent surface layer are shown in Table 4.

[0194] Example 13 A stainless steel substrate having a water-repellent surface layer was obtained in the same manner as in Comparative Example 10, except that the above-mentioned aqueous primer composition 7 was used. The film thicknesses of the primer layer and the water-repellent surface layer are shown in Table 4.

[0195] Comparative Example 12 A stainless steel substrate having a water-repellent surface layer was obtained in the same manner as in Comparative Example 10, except that the aqueous primer composition 6 was used. The film thicknesses of the primer layer and the water-repellent surface layer are shown in Table 4.

[0196] The stainless steel substrates having the water-repellent surface layers obtained in the above Examples and Comparative Examples were evaluated for initial water contact angle, nonwoven fabric abrasion resistance, and alkali resistance by the methods described below.

[0197] [Measurement of initial water contact angle] The water contact angle of the water-repellent surface layer of the stainless steel substrate was measured by the sessile drop method using a 2 μL droplet and θ / 2 analysis method using a contact angle meter Drop Master (manufactured by Kyowa Interface Science Co., Ltd.) in accordance with JIS R 3257: 1999. The measurement results are shown in Table 4.

[0198] [Nonwoven Fabric Abrasion Durability Test] The water-repellent surface layer of the stainless steel substrate was tested using a reciprocating abrasion tester (Type 40, manufactured by Shinto Scientific Co., Ltd.) under the following conditions. Abrasive: Bemcot (M-3II, manufactured by Ozu Sangyo Co., Ltd.) Load: 1 kgf Reciprocating distance: 40 mm Reciprocating speed: 40 reciprocations per minute Total number of reciprocating friction cycles: 10,000 cycles The water contact angle of the friction-wear portion was measured every 2,500 reciprocating friction cycles using the same method as above. The number of reciprocating abrasion cycles at which a water contact angle of 90° or more was maintained was taken as the nonwoven fabric abrasion durability cycle. In Comparative Example 10, the nonwoven fabric abrasion durability cycle was 10,000 cycles. The ratio of the number of reciprocating abrasion cycles of the nonwoven fabric of each Example and Comparative Example to the number of reciprocating abrasion cycles of the nonwoven fabric of Comparative Example 10, which is set to 100, is shown in Table 4 as the nonwoven fabric abrasion durability.

[0199] [Alkali Resistance Test] A stainless steel substrate having a water-repellent surface layer was immersed in a 0.4% by mass sodium hydroxide aqueous solution (test liquid) at 55°C. Every two hours, the substrate was removed from the test liquid. Pure water was poured over the water-repellent surface layer of the stainless steel substrate for one minute to remove the test liquid, and the surface moisture was removed by blowing dry air onto the substrate. The water contact angle of the water-repellent surface layer of the stainless steel substrate was then measured in the same manner as above. Immersion in the test liquid was repeated until the water contact angle fell below 90°, and the immersion time during which the water contact angle of 90° was maintained was defined as the alkali resistance time. In Comparative Example 10, the alkali resistance time was 4 hours. The alkali resistance is shown in Table 4, where Comparative Example 10 is set to 100, and the ratio of the alkali resistance time of each Example and Comparative Example to the alkali resistance time of Comparative Example 10.

[0200]

[0201] Comparing the results of Comparative Example 7 and Examples 8 to 10, Examples 8 to 10 all exhibited excellent chemical resistance and good steel wool abrasion resistance. Comparing the results of Comparative Example 10 and Examples 11 to 13, Examples 11 to 13 all exhibited excellent chemical resistance and water-repellent surface layers with excellent nonwoven fabric abrasion resistance. Furthermore, Comparative Examples 8 and 11, in which the primer layer was a SiO2 layer, exhibited inferior chemical resistance compared to the corresponding Examples and other Comparative Examples. Furthermore, Comparative Examples 9 and 12, which used Primer Composition 6, had a metal compound to silica nanoparticle ratio of 1000%, and therefore exhibited superior chemical resistance compared to Comparative Examples 7 and 10, but did not exhibit good abrasion resistance with either steel wool or nonwoven fabric.

[0202] [Comparative Example 13] [Alkaline Cleaning of Glass Substrate] A soda-lime glass substrate (size: 100 mm × 50 mm × 0.7 mm (thickness)) was immersed in an alkaline cleaning solution (an aqueous solution prepared by diluting Semiclean L.G.L manufactured by Yokohama Oil & Fat Industries Co., Ltd. to 5% by mass) and subjected to ultrasonic cleaning for 5 minutes. Thereafter, the substrate was immersed in ion-exchanged water and subjected to ultrasonic cleaning for 6 minutes. The moisture in the glass substrate was blown off with compressed air and the substrate was dried.

[0203] [Plasma Cleaning of Glass Substrate] The surface of the glass substrate that had been subjected to the above alkaline cleaning was treated with oxygen-argon mixed plasma. The treatment conditions are as follows: Treatment device: PDC510 (manufactured by Yamato Scientific Co., Ltd.) Oxygen gas flow rate: 10 sccm (Standard Cubic Centimeters) Argon gas flow rate: 100 sccm Treatment pressure: 60 Pa RF power supply: 250 W Treatment time: 30 seconds

[0204] [Formation of Primer Layer] The above aqueous primer composition 1 was dip-coated on a glass substrate that had been subjected to alkali cleaning and plasma cleaning, and then heated and dried to form a primer layer with a thickness of 4 nm. The dip-coating and heating conditions are as follows: Immersion time: 30 seconds, Pull-up speed: 0.5 mm / second, Heating conditions: 150°C, 30 minutes. The thickness of the primer layer was measured by X-ray reflectivity measurement.

[0205] [Preparation of Surface Treatment Agent III] The above compound (A) (number average molecular weight 4000) was dissolved in a fluorine-based solvent (NOVEC HFE-7200, ethyl perfluorobutyl ether, manufactured by 3M) to a concentration of 0.1% by mass to prepare surface treatment agent III.

[0206] [Formation of a water-repellent surface layer by dip coating] Surface treatment agent III was dip-coated onto a glass substrate on which a primer layer had been formed, and then cured to obtain a glass substrate having a water-repellent surface layer of a fluoropolyether group-containing polymer with a thickness of 10 nm. The dip-coating and curing conditions were as follows: Immersion time: 30 seconds, Pull-up speed: 10 mm / second, Curing conditions: 80°C, 80% relative humidity, 30 minutes. The thickness of the water-repellent surface layer was calculated using a calibration curve by quantifying the intensity of fluorescent X-rays derived from elemental fluorine using a fluorescent X-ray analyzer (manufactured by Rigaku Corporation, product name: fluorescent X-ray analyzer Primini).

[0207] The glass substrate having the obtained water-repellent surface layer was evaluated in the same manner as in Comparative Example 1. The results were that the initial water contact angle was 113°, the steel wool abrasion durability was 15,000 times, and the alkali resistance time was 16 hours.

[0208] Example 14 A glass substrate having a water-repellent surface layer was obtained in the same manner as in Comparative Example 13, except that the aqueous primer composition 2 was used. The film thickness of the primer layer measured in the same manner as in Comparative Example 13 was 5 nm, and the film thickness of the water-repellent surface layer was 10 nm. The glass substrate having the obtained water-repellent surface layer was evaluated in the same manner as in Comparative Example 1. The results were an initial water contact angle of 113°, a steel wool abrasion durability of 15,000 cycles, and an alkali resistance time of 28 hours. Compared to Comparative Examples 1 and 13, the steel wool abrasion durability was equivalent, and the alkali resistance was good.

Claims

1. An aqueous primer composition used for forming a primer layer on the outer surface of a substrate, and further having a water-repellent surface layer on the outer surface of the primer layer, wherein the primer composition contains silica nanoparticles and a metal compound containing any one or more of niobium, hafnium, zirconium, and tantalum, and contains the metal compound in a mass ratio of 5% or more and less than 1000% with respect to the silica nanoparticles.

2. The primer composition according to claim 1, wherein the average particle diameter of the silica nanoparticles is 0.1 to 50 nm.

3. The primer composition according to claim 1, wherein the metal compound is any one or more of niobium oxide, ammonium niobium oxalate, and niobium oxalate.

4. The primer composition according to claim 3, wherein the niobium oxide is niobium oxide nanoparticles having an average particle diameter of 0.1 to 20 nm.

5. The primer composition according to claim 1, wherein the metal compound is any one or more of ammonium zirconium carbonate, zirconium acetate, zirconium oxynitrate, zirconium nitrate, zirconium oxychloride, and chlorohydroxy zirconium.

6. The primer composition according to claim 1, wherein the substrate is a metal.

7. The primer composition according to claim 1, wherein the substrate is glass.

8. The primer composition according to claim 1, which is for building materials and household equipment.

9. The primer composition according to claim 1, which is for touch panels, windows, and lenses.

10. A water-repellent article having a primer layer with a film thickness of 1 to 50 nm containing a total of 50% by mass or more of silica nanoparticles and a metal oxide containing any one or more of niobium, hafnium, zirconium, and tantalum, and having a mass ratio of the metal oxide to the silica nanoparticles of 5% or more and less than 1000%, and having a water-repellent surface layer with a film thickness of 0.5 to 20 nm on the outer surface of the primer layer.

11. The water-repellent article according to claim 10, wherein the average particle diameter of the silica nanoparticles in the primer layer is 0.1 to 50 nm.

12. The water-repellent article according to claim 10, wherein the metal oxide in the primer layer is niobium oxide or zirconium oxide.

13. The water-repellent surface layer is represented by the following formula (1), (4), or (7): [In the formula, Rf is a divalent perfluoropolyether group, and A 1 is a monovalent fluorine-containing hydrocarbon group having a terminal of CF3- or CF2H- and optionally containing an oxygen atom, or D, and D is independently a monovalent group represented by the following formula (2). [In the formula, Q is a single bond or a divalent organic group, Z is a trivalent to octavalent group, α is an integer of 2 to 7, and W is independently a monovalent silanol group or a hydrolyzable silyl group-containing group represented by the following formula (3). (In the formula, R is an alkyl group having 1 to 4 carbon atoms or a phenyl group, X is independently a hydroxyl group or a hydrolyzable group, a is 2 or 3, and Y is a single bond, or a divalent hydrocarbon group which may have one or more selected from a fluorine atom, a silicon atom, and a siloxane bond.)]], [In the formula, Rf is the same as above, and A 2 is a monovalent fluorine-containing hydrocarbon group having a terminal of CF3- or CF2H- and optionally containing an oxygen atom, or G, and G is independently a monovalent group represented by the following formula (5). [In the formula, W is the same as above, B is a hydrogen atom, or -OS, and S is a hydrogen atom, a monovalent hydrocarbon group having 1 to 10 carbon atoms, or a monovalent group represented by the following formula (6). (In the formula, T is a single bond or a divalent group, L is independently a divalent hydrocarbon group having 1 to 4 carbon atoms, E is a monovalent hydrocarbon group having 1 to 6 carbon atoms, or W, and l is an integer of 0 to 20.)]], [In the formula, Rf is the same as above, and A 3 is a monovalent fluorine-containing hydrocarbon group having a terminal of CF3- or CF2H- and optionally containing an oxygen atom, or J, and J is independently a monovalent group represented by the following formula (8) and has two or more Ws in J. [In the formula, S is the same as above, V is a single bond or a divalent hydrocarbon group having 2 to 15 carbon atoms which may have an ether bond, M is independently a monovalent group represented by the following formula (9), (wherein Y, S, and W are the same as described above, and f is an integer of 1 to 3.) e is 1 or 2.]] The water-repellent article according to claim 10, which is a cured product of a surface treatment agent containing a fluoropolyether group-containing polymer having one or more silanol groups or hydrolyzable silyl groups represented by and / or a partial (hydrolytic) condensate thereof.

14. The water-repellent surface layer is represented by the following formula (11), (12) or (13) (In the formula, A is a monovalent hydrocarbon group having 1 to 50 carbon atoms, B 1 is a hydrogen atom or a hydroxyl group, E 1 is a hydrogen atom or a monovalent hydrocarbon group having 1 to 50 carbon atoms, and the total number of carbon atoms contained in A and E 1 is 12 or more, Y 1 is a single bond or a divalent hydrocarbon group which may have one or more selected from a silicon atom and a siloxane bond, R is an alkyl group having 1 to 4 carbon atoms or a phenyl group, X 1 is independently a hydrolyzable group, and z is 2 or 3.) (In the formula, A, B 1 , E 1 , Y 1 are the same as above, y is a number from 0 to 3, x is (3 - y) / 2, and when y = 3, formula (12) represents the molecular formula of a monomer, and when y < 3, formula (12) represents the compositional formula of a polymer.) (In the formula, G 1 is independently a monovalent hydrocarbon group having 8 to 30 carbon atoms, and J 1 is independently a hydrogen atom, a hydroxyl group or a methyl group.) The water-repellent article according to claim 10, which is a cured product of a surface treatment agent containing a fluorine atom-free alkyl group-containing compound having a hydrolyzable silyl group represented by the formula and / or a partial hydrolysis condensate thereof.

15. The water-repellent article according to claim 10, wherein the substrate is a metal.

16. The water-repellent article according to claim 10, wherein the substrate is glass.

17. The water-repellent article according to claim 10, which is for building materials and household equipment.

18. The water-repellent article according to claim 10, which is for a touch panel, a window, or a lens.

19. A method for manufacturing the water-repellent article according to claim 10, comprising forming a primer layer by a wet coating method using the primer composition according to any one of claims 1 to 9, and forming a water-repellent surface layer by a wet coating method.

20. A method for manufacturing the water-repellent article according to claim 10, comprising forming a primer layer by a wet coating method using the primer composition according to any one of claims 1 to 9, and forming a water-repellent surface layer by a dry coating method.

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