Method for forming a hydrophilic antifouling layer, hydrophilic antifouling composition, and hydrophilic antifouling laminate

Abstract

The present invention aims to provide a method for forming a hydrophilic and antifouling layer that has a low environmental impact, excellent manufacturability, a simple layer structure, and an excellent balance of hydrophilicity and antifouling properties; a hydrophilic and antifouling composition for forming the hydrophilic and antifouling layer; a method for forming the hydrophilic and antifouling layer; or a hydrophilic and antifouling laminate formed from the hydrophilic and antifouling composition. [Means for solving the problem] A method for forming a hydrophilic antifouling layer, wherein a hydrophilic antifouling layer is formed on a substrate layer by applying a hydrophilic antifouling material, a specific hydrophilicity enhancing treatment agent is applied to the surface of the hydrophilic antifouling layer to form a hydrophilicity-enhancing treated surface, the thickness of the hydrophilic antifouling layer is 10 nm or more and 1000 nm or less, and the contact angle of the surface of the hydrophilicity-enhancing treated surface immediately after surface treatment is 1 degree or more and less than 40 degrees.

Description

Technical Field

[0001] The present invention relates to a method for forming a hydrophilic antifouling layer having a small environmental impact, excellent manufacturing suitability, a simple layer structure, and an excellent balance between hydrophilicity and antifouling properties, a hydrophilic antifouling composition for forming the hydrophilic antifouling layer, a method for forming the hydrophilic antifouling layer, or an antifouling laminate formed from the hydrophilic antifouling composition.

Background Art

[0002] Generally, an antifouling layer is formed by spray-treating a treatment agent containing a fluorine-based silane coupling agent to adhere to a substrate and impart water repellency. However, since the fluorine-based silane coupling agent is hardly compatible with general solvents, it is necessary to dilute it with a fluorine-based solvent, resulting in a large environmental impact and high cost (Patent Documents 1 to 4).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present invention is to provide a method for forming a hydrophilic antifouling layer having a small environmental impact without using hydrofluoric acid or fluorine-based solvents, excellent manufacturing suitability, a simple layer structure, and an excellent balance between hydrophilicity, antifouling properties, and interference-free colorless transparency, a hydrophilic antifouling composition for forming the hydrophilic antifouling layer, a method for forming the hydrophilic antifouling layer, or a hydrophilic antifouling laminate formed from the hydrophilic antifouling composition.

Means for Solving the Problems

[0005] As a result of various studies, the inventors have found that a method for forming a hydrophilic antifouling layer, which involves applying a specific hydrophilic antifouling material to a substrate to form a hydrophilic antifouling layer, and then surface-treating the surface of the hydrophilic antifouling layer with a specific hydrophilicity-enhancing treatment agent, can achieve the above objectives. In other words, the present invention is characterized by the following: [1] A method for forming a hydrophilic antifouling layer, comprising forming a hydrophilic antifouling layer on a substrate layer by applying a hydrophilic antifouling material, and forming a hydrophilic enhanced surface by applying a hydrophilicity enhancing treatment agent to the surface of the hydrophilic antifouling layer, The surface of the substrate layer on which the hydrophilic antifouling layer is formed is made of organic and / or inorganic materials. The hydrophilic antifouling material consists of a hydrophilic antifouling composition. The hydrophilic antifouling composition contains an alkyl silicate resin (A) and a solvent (B), does not contain fine particles with a particle size of 5 nm or larger, and has a viscosity of 0.5 to 1000 mPa·s. Alkyl silicate resin (A) has alkoxysilyl groups and a weight-average molecular weight of 1,000 to 100,000. The content of alkyl silicate resin (A) in the hydrophilic antifouling composition is 0.01 to 10% by mass. The thickness of the hydrophilic antifouling layer is 10 nm or more and 1000 nm or less. The hydrophilicity-enhancing treatment agent contains an oxidizing agent (F) and a solvent (I), The oxidizing agent (F) contains hydrogen peroxide. The hydrogen peroxide content in the hydrophilicity-enhancing treatment agent is 0.01 to 5% by mass. The contact angle of the surface immediately after surface treatment of the hydrophilicity-enhancing treated surface is 1 degree or more and less than 40 degrees. A method for forming a hydrophilic antifouling layer. [2] The hydrophilic antifouling composition further contains an adhesion agent (C) and / or a hydrophilic agent (D), Adhesion-enhancing agent (C) contains a silicone-modified acrylic polymer, The hydrophilicity-imparting agent (D) contains a compound having a sulfonic acid group, The content of adhesion-imparting agent (C) in the hydrophilic antifouling composition is 0% by mass, or 0.01 to 1% by mass. The content of the hydrophilicity imparting agent (D) in the hydrophilic antifouling composition is 0% by mass, or 0.01 to 10% by mass. The method for forming a hydrophilic antifouling layer as described in [1] above. [3] The hydrophilicity-enhancing agent further contains an alkyl silicate resin (E) and a basic compound (G) and / or a hydrophilicity-imparting agent (H), and does not contain fine particles with a particle size of 5 nm or larger. The pH of the hydrophilicity-enhancing treatment agent is 8 to 11. Alkyl silicate resin (E) has an alkoxysilyl group and a weight-average molecular weight of 1,000 to 100,000. The hydrophilicity-imparting agent (H) contains one or more selected from the group consisting of an acrylic polymer having a sulfonic acid group, a sulfonic acid-modified silicate, and sodium sulfosuccinate. The content of alkyl silicate resin (E) in the hydrophilicity-enhancing treatment agent is 0.01 to 5% by mass. The content of the basic compound (G) in the hydrophilicity-enhancing treatment agent is 0% by mass, or 0.01 to 5% by mass. The content of the hydrophilicity-enhancing agent (H) in the hydrophilicity-enhancing treatment agent is 0% by mass, or 0.01 to 5% by mass. The method for forming a hydrophilic antifouling layer as described in [1] above. [4] The method for forming the hydrophilic antifouling layer described in [1] above, comprising the following steps 1 to 5 in this order. Step 1: Applying a hydrophilic antifouling agent to the substrate layer. Step 2: Drying and curing the applied hydrophilic antifouling agent. Step 3: Applying a hydrophilicity-enhancing treatment agent. Step 4: Drying the applied hydrophilicity-enhancing treatment agent. Step 5: Wipe the hydrophilic treated surface with water. [5] The method for forming a hydrophilic antifouling layer according to [4] above, wherein the hydrophilic antifouling material of step 1 and / or the hydrophilicity enhancing treatment agent of step 3 are applied in a cross-coat. [6] The method for forming a hydrophilic antifouling layer according to [4] above, wherein the hydrophilic antifouling material of step 2 is dried and cured at 10 to 40 degrees Celsius for 1 to 60 minutes. [7] The hydrophilicity-enhancing treatment agent of step 4 is dried at 10 to 40°C for 1 to 60 minutes, in the method for forming a hydrophilic antifouling layer as described in [4] above. [8] A hydrophilic antifouling laminate having a base layer and a hydrophilic antifouling layer adjacent to the base layer, The surface of the substrate layer facing the hydrophilic antifouling layer is made of organic and / or inorganic materials. The hydrophilic antifouling layer is the surface layer of the hydrophilic antifouling laminate, and is a layer formed by the method for forming a hydrophilic antifouling layer described in any one of the above items [1] to [7], and does not exhibit interference colors, is colorless and transparent, The thickness of the hydrophilic antifouling layer is 10 nm or more and 1000 nm or less. The contact angle of the surface of the hydrophilic-enhancing treated surface of the hydrophilic antifouling layer immediately after surface treatment is 1 degree or more and less than 40 degrees. Hydrophilic antifouling laminate. [9] A hydrophilic antifouling composition which is applied adjacent to the surface of an organic and / or inorganic substrate layer, dried and cured, The hydrophilic antifouling composition contains an alkyl silicate resin (A) and a solvent (B), and does not contain fine particles with a particle size of 5 nm or larger. Alkyl silicate resin (A) has alkoxysilyl groups and a weight-average molecular weight of 1,000 to 100,000. The content of alkyl silicate resin (A) in the hydrophilic antifouling composition is 0.01 to 10% by mass. The viscosity of the hydrophilic antifouling composition is 0.5 to 1000 mPa·s. Hydrophilic antifouling composition.

[10] The hydrophilic antifouling composition further contains an adhesion agent (C) and / or a hydrophilic agent (D), Adhesion-enhancing agent (C) contains a silicone-modified acrylic polymer, The hydrophilicity-imparting agent (D) contains a compound having a sulfonic acid group, The content of the adhesion-imparting agent (C) in the hydrophilic antifouling composition is 0% by mass, or 0.01 to 1% by mass. The content of the hydrophilic agent (D) in the hydrophilic antifouling composition is 0% by mass, or 0.01 to 10% by mass. The hydrophilic antifouling composition according to [9] above.

[11] A hydrophilic antifouling laminate having a base material layer and a hydrophilic antifouling layer adjacent to the base material layer, The surface of the base material layer on the hydrophilic antifouling layer side is made of an organic substance and / or an inorganic substance, The hydrophilic antifouling layer is the surface layer of the hydrophilic antifouling laminate and is composed of the hydrophilic antifouling composition according to [9] or

[10] above, and has a thickness of 10 nm or more and 1 μm or less. The surface of the hydrophilic antifouling layer is a hydrophilicity-increasing treatment surface surface-treated with a hydrophilicity-enhancing treatment agent, and the contact angle immediately after the surface treatment is 1 degree or more and less than 40 degrees. The hydrophilicity-enhancing treatment agent contains an alkyl silicate resin (E), an oxidizing agent (F), a basic compound (G) and / or a hydrophilic agent (H), and a solvent (I), has a viscosity of 0.5 to 1000 mPa·s, a pH of 8 to 11, and does not contain fine particles having a particle size of 5 nm or more. The content of the oxidizing agent (F) in the hydrophilicity-enhancing treatment agent is 0.01 to 5% by mass. The alkyl silicate resin (E) has an alkoxysilyl group and a weight average molecular weight of 1,000 to 100,000. The oxidizing agent (F) contains hydrogen peroxide. <000009​​​​​​​​​​​​​According to the present invention, it is possible to obtain a method for forming a hydrophilic antifouling layer that does not use hydrofluoric acid or fluorine-based solvents, has low environmental impact, excellent manufacturability, and a simple layer structure that provides an excellent balance of hydrophilicity, antifouling properties, and colorless transparency without interference colors; a hydrophilic antifouling composition for forming the hydrophilic antifouling layer; a method for forming the hydrophilic antifouling layer; or a hydrophilic antifouling laminate formed from the hydrophilic antifouling composition. [Brief explanation of the drawing]

[0007] [Figure 1] This is a cross-sectional view of the hydrophilic antifouling laminate of the present invention. [Modes for carrying out the invention]

[0008] The present invention relates to a method for forming a hydrophilic antifouling layer that has an excellent balance of hydrophilicity, antifouling properties, and colorless transparency, a hydrophilic antifouling composition for forming the hydrophilic antifouling layer, and a hydrophilic antifouling laminate formed from the method for forming the hydrophilic antifouling layer or the hydrophilic antifouling composition.

[0009] I. Hydrophilic antifouling compositions The hydrophilic antifouling composition of the present invention is a hydrophilic antifouling material, which is applied adjacent to the surface of a substrate layer and dried to form a hydrophilic antifouling layer. The hydrophilic antifouling composition contains an alkyl silicate resin (A) and a solvent (B), and may further contain an adhesion promoter (C) and / or a hydrophilicity promoter (D).

[0010] It is preferable that the hydrophilic antifouling composition does not contain fine particles with a particle size of 5 nm or larger. When a hydrophilic antifouling composition contains fine particles with a particle size of 5 nm or larger, the smoothness of the surface of the hydrophilic antifouling layer decreases, it becomes difficult to obtain a uniform, transparent appearance without interference colors, and the hydrophilicity tends to decrease after outdoor exposure. The viscosity of the hydrophilic antifouling composition is preferably 0.5 to 1000 mPa·s, and more preferably 0.8 to 100 mPa·s. Lowering the viscosity of the hydrophilic antifouling composition below the above range is difficult without significantly improving the applicability or hydrophilic antifouling properties, while higher viscosities tend to make uniform application difficult.

[0011] The content of alkyl silicate resin (A) in the hydrophilic antifouling composition is preferably 0.01 to 10% by mass, and more preferably 0.05 to 5% by mass. If the content of alkyl silicate resin (A) is less than the above range, the hydrophilic antifouling layer will not exhibit sufficient antifouling properties and hydrophilicity, and if it is more than the above range, the antifouling properties and hydrophilicity will not improve significantly, and the viscosity will increase, making it easy to reduce the applicability.

[0012] If the hydrophilic antifouling composition does not contain an adhesion promoter (C), the content of the adhesion promoter (C) in the hydrophilic antifouling composition is 0% by mass. However, if the hydrophilic antifouling composition contains an adhesion promoter (C), the content of the adhesion promoter (C) in the hydrophilic antifouling composition is preferably 0.01 to 1% by mass, and more preferably 0.02 to 1% by mass. If the content of the adhesion promoter (C) is less than the above range, it is difficult to obtain a sufficient adhesion improvement effect, and if it is more than the above range, the adhesion improvement effect does not improve much, and the viscosity tends to increase, making it difficult to apply.

[0013] When a hydrophilic antifouling composition does not contain a hydrophilic agent (D), the content of the hydrophilic agent (D) in the composition is 0% by mass. However, when a hydrophilic antifouling composition contains a hydrophilic agent (D), the content of the hydrophilic agent (D) in the composition is preferably 0.01 to 10% by mass, and more preferably 0.02 to 1% by mass. If the content of the hydrophilic agent (D) is less than the above range, it is difficult to obtain a sufficient hydrophilic improvement effect, and if it is more than the above range, the hydrophilic improvement effect does not improve much, and the viscosity tends to increase, making it difficult to apply.

[0014] II. Hydrophilicity-enhancing agents The hydrophilicity-enhancing treatment agent is a treatment agent that increases the hydrophilicity of the surface of the hydrophilic antifouling layer in the present invention. The hydrophilicity-enhancing agent contains an oxidizing agent (F) and a solvent (I), and may further contain an alkyl silicate resin (E), a basic compound (G), and / or a hydrophilicity-imparting agent (H). In order to maintain the surface smoothness of the hydrophilic antifouling layer after surface treatment to the same extent as before treatment, it is preferable that the hydrophilicity enhancing agent does not contain fine particles with a particle size of 5 nm or larger.

[0015] The oxidizing agent (F) hydrolyzes the surface of the hydrophilic antifouling layer, thereby improving its hydrophilicity. The alkyl silicate resin (E) and the basic compound (G) and / or hydrophilicity-imparting agent (H) produce an effect that improves the hydrophilicity of the surface of the hydrophilic antifouling layer by hydrolysis or functional group substitution.

[0016] The viscosity of the hydrophilicity-enhancing agent is preferably between 0.5 and 1000 mPa·s. It is difficult to reduce the viscosity of the hydrophilicity-enhancing agent below this range without changing the application and processing properties, while a viscosity higher than this range makes it difficult to obtain uniform application and surface treatment. The pH of the hydrophilicity-enhancing treatment agent is preferably 8 to 11, and more preferably 8.5 to 10.5. If the pH of the hydrophilicity-enhancing treatment agent is within the above range, an excellent treatment effect can be obtained on the surface of the hydrophilic antifouling layer in the present invention.

[0017] The content of the oxidizing agent (F) in the hydrophilicity-enhancing treatment agent is preferably 0.01 to 5% by mass, and more preferably 0.05 to 1% by mass. If the content of the oxidizing agent (F) is less than the above range, it is difficult to obtain sufficient adhesion and hydrophilicity, and if it is more than the above range, the adhesion and hydrophilicity do not improve significantly.

[0018] The content of alkyl silicate resin (E) in the hydrophilicity enhancing agent is preferably 0.01 to 5% by mass, and more preferably 0.02 to 2% by mass. If the content of the hydrophilicity imparting agent (E) is less than the above range, it is difficult to obtain a sufficient hydrophilicity improvement effect, and if it is more than the above range, the hydrophilicity improvement effect does not improve much, and viscosity tends to increase, reducing the applicability.

[0019] When the hydrophilicity enhancing agent does not contain basic compound (G), the content of basic compound (G) in the hydrophilicity enhancing agent is 0% by mass. However, when the hydrophilicity enhancing agent contains basic compound (G), the content of basic compound (G) in the hydrophilicity enhancing agent is preferably 0.01 to 5% by mass, and more preferably 0.05 to 1% by mass. If the content of basic compound (G) is less than the above range, it is difficult to obtain sufficient hydrophilicity, and if it is more than the above range, the hydrophilicity does not improve significantly.

[0020] The hydrophilicity enhancing agent does not need to contain hydrophilicity imparting agent (H); that is, the content of hydrophilicity imparting agent (H) in the hydrophilicity enhancing agent may be 0% by mass. However, if the hydrophilicity enhancing agent does contain hydrophilicity imparting agent (H), the content of hydrophilicity imparting agent (H) in the hydrophilicity enhancing agent is preferably 0.01 to 5% by mass, and more preferably 0.1 to 2% by mass.

[0021] III. About Raw Materials [Base material] The substrate layer is the object to be coated with the hydrophilic antifouling composition of the present invention. There are no particular restrictions on the material of the base material constituting the base layer; it may be an organic material, an inorganic material, or a mixture of organic and inorganic materials. In particular, the material of the surface of the substrate layer adjacent to the hydrophilic antifouling layer is made of organic and / or inorganic materials, and may be organic, inorganic, or a mixture of organic and inorganic materials. Examples of inorganic materials include metal oxides, while examples of organic materials include resins. Examples of substrates using metal oxides include ceramic plates, glass plates, and glass cloth. Examples of resin-based substrates include polymethyl methacrylate (PMMA) sheets, polycarbonate (PC) sheets, and polyethylene terephthalate (PET) sheets.

[0022] [Alkyl silicate resin (A), Alkyl silicate resin (E)] Alkyl silicate resin (A) and alkyl silicate resin (E) are silicate resins having alkoxysilyl groups and are soluble in solvent (B) and solvent (I), respectively. Alkyl silicate resin (A) and alkyl silicate resin (E) may be the same or different. Alkyl silicate resin (A) and alkyl silicate resin (E) may be, for example, a mixture of polyalkyl silicate and tetraalkoxysilane, γ-glycidylpropyl-trialkoxysilane, γ-aminopropyl-trialkoxysilane, etc., or may be partial reaction products thereof. The weight-average molecular weight of alkyl silicate resin (A) and alkyl silicate resin (E) is preferably between 1,000 and 1,000,000.

[0023] [Solvent (B), Solvent (I)] Solvent (B) and solvent (I) are solvents that dissolve alkyl silicate resin (A) and alkyl silicate resin (E), respectively, and solvent (B) and solvent (I) may be the same or different. The solvent (B) and solvent (I) preferably contain water and / or an aqueous solvent. Examples of such aqueous solvents include alcohol-based solvents, glycol-based solvents, alkylene glycol ethers, ester-based solvents, and polar solvents, and it is preferable to use one or more selected from the group consisting of these. Among the above, solvents (B) and (I) more preferably contain water and / or ethanol. The presence of water in solvents (B) and (I) facilitates the hydrolysis and functional group substitution of alkyl silicate resins (A) and (E). Furthermore, solvents contained as solvents in other raw materials contained in the hydrophilic antifouling composition or hydrophilicity enhancing treatment agent may be considered as solvent (B) or solvent (I) and used as is.

[0024] When drying the hydrophilic antifouling composition or hydrophilicity enhancing treatment agent of the present invention at, for example, 10 to 40°C, the boiling points of the solvents contained in solvent (B) and solvent (I) are preferably 50 to 120°C, and more preferably 60 to 90°C. By including solvents with boiling points within the above range, it becomes easier to make the hydrophilic antifouling layer smoother and obtain an excellent appearance.

[0025] Specific examples of alcohol-based solvents include methanol (1 carbon atom, boiling point 65°C), ethanol (2 carbon atoms, boiling point 78°C), n-propanol (3 carbon atoms, boiling point 97°C), isopropyl alcohol (3 carbon atoms, boiling point 82°C), tert-butanol (4 carbon atoms, boiling point 82°C), n-butanol (4 carbon atoms, boiling point 118°C), isobutanol (4 carbon atoms, boiling point 108°C), and deuterated butanol. Examples include ethanol (4 carbon atoms, boiling point 100°C), 1-pentanol (5 carbon atoms, boiling point 138°C), 2-methyl-1-butanol (5 carbon atoms, boiling point 128°C), 3-methyl-1-butanol (5 carbon atoms, boiling point 131°C), 2-pentanol (5 carbon atoms, boiling point 119°C), 1-ethyl-1-propanol (5 carbon atoms, boiling point 116°C), and 2-methyl-2-butanol (5 carbon atoms, boiling point 102°C). Among these, ethanol is preferred.

[0026] Specific examples of glycol-based solvents include alkylene glycols and alkylene glycol ethers. Specific examples of alkylene glycols include ethylene glycol (2 carbon atoms, boiling point 197°C), propylene glycol (3 carbon atoms, boiling point 189°C), butylene glycol (4 carbon atoms, boiling point 207°C), hexylene glycol (6 carbon atoms, boiling point 197°C), and octylene glycol (8 carbon atoms, boiling point 175°C).

[0027] Specific examples of alkylene glycol ethers include ethylene glycol monomethyl ether (3 carbon atoms, boiling point 124°C), ethylene glycol monoethyl ether (4 carbon atoms, boiling point 135°C), ethylene glycol diethyl ether (6 carbon atoms, boiling point 121°C), ethylene glycol monoisopropyl ether (5 carbon atoms, boiling point 141°C), ethylene glycol monobutyl ether (6 carbon atoms, boiling point 171°C), propylene glycol monomethyl ether (4 carbon atoms, boiling point 120°C), propylene glycol monoethyl ether (5 carbon atoms, boiling point 132°C), propylene glycol monon-propyl ether (6 carbon atoms, boiling point 149°C), and propylene glycol monon-butyl ether (7 carbon atoms, boiling point 171°C). Among these, propylene glycol monomethyl ether is preferred. In the present invention, the above compounds can be used as the solvent (H) individually or in combination of two or more.

[0028] [Adhesion-enhancing agent (C)] Adhesion-enhancing agent (C) is an additive that improves the adhesion of hydrophilic antifouling compositions. Examples of additives that provide such improved adhesion include silicon-modified acrylic polymers and amine-modified silanols. It is preferable to use one or more selected from this group depending on the material of the surface of the substrate layer. For example, if the surface of the substrate layer contains an acrylic resin, the adhesion promoter (C) preferably contains a silicon-modified acrylic polymer. The acrylic polymer portion of the silicon-modified acrylic polymer adheres to the acrylic resin portion of the substrate surface, and the silicon portion of the silicon-modified acrylic polymer reacts with and bonds to the alkyl silicate resin (A) in the hydrophilic antifouling composition, thereby improving the adhesion between the substrate layer and the hydrophilic antifouling layer.

[0029] [Hydrophilicity-enhancing agent (D), Hydrophilicity-enhancing agent (H)] Hydrophilicity imparting agent (D) and hydrophilicity imparting agent (H) are additives that impart improved hydrophilicity to hydrophilic antifouling compositions and hydrophilicity enhancing treatment agents. Hydrophilicity imparting agent (D) and hydrophilicity imparting agent (H) may be the same or different. The hydrophilicity imparting agent (D) and hydrophilicity imparting agent (H) preferably contain compounds having a sulfonic acid group. Examples of compounds having a sulfonic acid group include sulfonic acid-modified silicates, acrylic polymers having a sulfonic acid group, sodium sulfosuccinate, and 2-acrylamido-2-methylpropanesulfonic acid. It is preferable to use one or more selected from the group consisting of these compounds.

[0030] Among these, sulfonic acid-modified silicates are more preferred. The sulfonic acid-modified silicates in hydrophilicity imparting agents (D) and (H) condense with the alkyl silicate resin (A) in the hydrophilic antifouling composition and the alkyl silicate resin (E) in the hydrophilicity enhancing treatment agent to increase their molecular weight, thereby improving adhesion to the substrate layer, reducing solubility in water, and enhancing hydrophilicity through the sulfonic acid groups.

[0031] [Oxidizing agent (F)] The oxidizing agent (F) contains compounds that have hydrolytic or functional group substitution effects on the alkyl silicate resin (A). Examples of compounds having such hydrolytic or functional group substitution effects include hydrogen peroxide and sodium nitrite, and it is preferable to use one or more selected from the group consisting of these. Among these, hydrogen peroxide is preferred due to its superior cost-effectiveness and convenience.

[0032] [Basic compounds (G)] Basic compound (G) is a pH adjuster used to adjust the pH of the hydrophilicity enhancing agent in order to regulate the hydrolysis and dehydration condensation reactions of alkyl silicate resin (A), alkyl silicate resin (E), hydrophilicity imparter (D), and hydrophilicity imparter (H). Examples of basic compounds (G) include ammonia, dimethylethanolamine, and triethylamine, and it is preferable to use one or more selected from the group consisting of these. Among these, ammonia is preferred due to its superior cost-effectiveness and convenience, and it is even more preferred to use it in the form of aqueous ammonia.

[0033] IV. Hydrophilic antifouling laminate The hydrophilic antifouling laminate of the present invention is a hydrophilic antifouling laminate having a base layer and a hydrophilic antifouling layer adjacent to the base layer, wherein the hydrophilic antifouling layer is the surface layer of the hydrophilic antifouling laminate. The surface of the substrate layer on the hydrophilic antifouling layer side is formed of a substrate consisting of organic and / or inorganic materials. The hydrophilic antifouling layer is a layer formed by the method for forming a hydrophilic antifouling layer of the present invention, using the hydrophilic antifouling composition and hydrophilicity enhancing treatment agent of the present invention.

[0034] The surface of the hydrophilic antifouling layer is a hydrophilic-enhancing treated surface, which has been treated with a hydrophilicity-enhancing agent. The contact angle immediately after surface treatment is preferably 1 degree or more and less than 40 degrees, and more preferably 2 degrees or more and less than 30 degrees. It is difficult to make the contact angle smaller than the above range immediately after formation, and if the contact angle is greater than the above range, it is difficult to obtain sufficient hydrophilicity. The contact angle after a cycle test, such as immersion in deionized water for 8 hours followed by drying at 80°C for 16 hours (10 cycles), is preferably 10 degrees or more and less than 40 degrees, and more preferably 10 degrees or more and less than 35 degrees. It is difficult to make the contact angle smaller than the above range, and if the contact angle is above the above range, it is difficult to obtain sufficient hydrophilicity. The contact angle after exposure tests, such as 90 days of outdoor exposure, is preferably 10 degrees or more and less than 40 degrees, and more preferably 10 degrees or more and less than 30 degrees. It is difficult to make the contact angle smaller than the above range, and if the contact angle is above the above range, it is difficult to obtain sufficient hydrophilicity.

[0035] The thickness of the hydrophilic antifouling layer is preferably 10 nm or more and 1000 nm or less, and more preferably 20 nm or more and 200 nm or less. If the thickness of the hydrophilic antifouling layer is thinner than the above range, it will be difficult to obtain sufficient hydrophilic antifouling properties, and if it is thicker than the above range, the rigidity of the hydrophilic antifouling laminate may become too high or the transparency uniformity of the hydrophilic antifouling layer may decrease. Furthermore, it is preferable that the appearance of the hydrophilic antifouling layer is colorless and transparent, without exhibiting interference colors, despite the thinness of the layer as described above.

[0036] V. Method for forming a hydrophilic fouling repellent layer The present invention provides a method for forming a hydrophilic antifouling layer, which involves forming a hydrophilic antifouling layer on a substrate layer by applying a hydrophilic antifouling material consisting of a hydrophilic antifouling composition, and then applying a hydrophilicity enhancing treatment agent to the surface of the hydrophilic antifouling layer to form a hydrophilicity-enhancing treated surface. The method preferably includes the following steps 1 to 5 in this order.

[0037] Step 1: Applying a hydrophilic antifouling agent to the substrate layer. Step 2: Drying and curing the applied hydrophilic antifouling agent. Step 3: Applying a hydrophilicity-enhancing treatment agent. Step 4: Drying the applied hydrophilicity-enhancing treatment agent. Step 5: Wipe the hydrophilic treated surface with water.

[0038] There are no particular restrictions on the method of applying the hydrophilic antifouling agent in step 1 described above, but it can be done by, for example, cloth application, spray coating, spin coating, roll coating, or immersion. Among these, cloth application using a microfiber cloth is preferred because it is simple.

[0039] In step 2 described above, the drying and curing of the hydrophilic antifouling material is preferably carried out at 10 to 40°C for 1 to 60 minutes, and more preferably at 15 to 30°C for 2 to 20 minutes. If the temperature is lower or the time is shorter than the above range, the curing of the hydrophilic antifouling layer may be insufficient, and if the temperature is higher or the time is longer than the above range, the hydrophilicity of the surface of the hydrophilic antifouling layer may decrease. Step 2 may further include wiping the surface of the dried and cured hydrophilic antifouling material with water. Wiping with water can improve the smoothness of the surface of the dried and cured hydrophilic antifouling material and remove any unreacted material. There are no particular restrictions on the method of wiping with water, but examples include wiping with a cloth such as a microfiber cloth, spraying with water, and wiping with a sponge. Among these, wiping with a cloth such as a microfiber cloth is preferred.

[0040] The method of applying the hydrophilicity-enhancing agent in step 3 described above is not particularly limited, but can be done by, for example, cloth coating, spray coating, spin coating, roll coating, or immersion. Among these, cloth coating is preferred because it is simple.

[0041] In step 4 described above, the drying of the hydrophilicity-enhancing treatment agent is preferably carried out at 10 to 40°C for 1 to 60 minutes, and more preferably at 15 to 30°C for 2 to 20 minutes. If the temperature is lower or the drying time is shorter than the above range, the hardening of the hydrophilic antifouling layer may be insufficient, and if the temperature is higher or the drying time is longer than the above range, the hydrophilicity of the hydrophilicity-enhancing treatment surface may decrease.

[0042] Step 5 described above is a process to improve the smoothness of the hydrophilic treated surface and remove any unreacted materials by wiping it with water. There are no particular restrictions on the method of wiping with water, but examples include wiping with a cloth such as a microfiber cloth, spraying with water, and wiping with a sponge. Among these, wiping with a cloth such as a microfiber cloth is preferred. [Examples]

[0043] The present invention will be specifically described below with reference to examples. The present invention is not limited to the following examples. The raw materials used in the example are as follows:

[0044] <Ingredients> [Alkyl silicate resin] • Alkyl silicate resin 1: Silicate 40 manufactured by Tama Chemical Industry Co., Ltd. It is a mixture of polyethyl silicate, tetraethoxysilane, and a solvent, with 100% by mass of non-volatile content. 60-70% by mass of the non-volatile content is polyethyl silicate. The weight-average molecular weight is 750. • Alkyl silicate resin 2: KR517 manufactured by Shin-Etsu Silicone Co., Ltd. A polysilicate resin having γ-glycidylpropylsilyl groups, methoxysilyl groups, and ethoxysilyl groups, and is a trimer of γ-glycidylpropyl-trialkoxysilane. Epoxy equivalent weight 830 g / mol. Non-volatile content 100% by mass.

[0045] [Adhesion-enhancing agent] • Adhesion enhancer 1: 8SQ-1100 manufactured by Taisei Fine Chemical Co., Ltd. Silicone-modified acrylic polymer, 50% by mass of non-volatile content.

[0046] [Hydrophilicity-imparting agent] • Hydrophilicity-imparting agent 1: Aron A6012, manufactured by Toagosei Co., Ltd. An acrylic polymer having sulfonic acid groups. Non-volatile content 40% by mass. • Hydrophilicity-imparting agent 2: LAMBIC-1000W manufactured by Osaka Organic Chemical Industry Co., Ltd. Sulfonic acid-modified silicate, 10% by mass of non-volatile content. • Hydrophilicity-imparting agent 3: Perex SSH manufactured by Kao Corporation. Sodium sulfosuccinate, 50% by mass of non-volatile content.

[0047] [Basic compounds] Basic compound 1: 28% aqueous ammonia • Hydrogen peroxide 1:35% hydrogen peroxide [Colloidal Silica] • Colloidal Silica 1: Snowtex manufactured by Nissan Chemical Corporation. Colloidal silica, 20% by mass of non-volatile content. Particle size 12 nm. [Base material] • Base material 1: Polycarbonate base material.

[0048] <Example of synthesis> [Preparation of Nitrate Solution 1] The following were mixed to obtain nitric acid solution 1 as a catalyst. 10% nitric acid aqueous solution 1.0 parts by mass Water 3.0 parts by mass Ethanol 30 parts by mass

[0049] [Synthesis of alkyl silicate resin 3] First, the following were mixed to obtain a mixed solution. Alkyl silicate resin 1: 8.0 parts by mass Ethanol 30 parts by mass Then, 34 parts by mass of nitric acid solution 1 obtained above was added dropwise while stirring and mixing at 40°C for 1 hour. Next, the following were added and stirred to obtain a 4% solids solution containing alkyl silicate resin 3. Ethanol 28.0 parts by mass The weight-average molecular weight of the obtained alkyl silicate resin 3 was 4000.

[0050] [Synthesis of alkyl silicate resins 4-8] Alkyl silicate resins 2 to 8 were obtained by following the formulations and conditions shown in Table 1, in the same manner as with alkyl silicate resin 1.

[0051] [Table 1]

[0052] [Preparation of hydrophilicity enhancing agent 1] The following raw materials were stirred and mixed at 40°C for 1.5 hours to obtain hydrophilicity-enhancing treatment agent 1. Hydrogen peroxide solution: 1 0.6 parts by mass Deionized water 99.4 parts by mass

[0053] [Preparation of hydrophilicity enhancing agents 2-7] Hydrophilicity-enhancing agents 2 to 7 were obtained by following the formulations shown in Table 2, in the same manner as the preparation of hydrophilicity-enhancing agent 1.

[0054] [Table 2]

[0055] <Examples> [Example 1] The following was stirred and mixed at 40°C for 1.5 hours to obtain hydrophilic antifouling material 1. Alkyl silicate resin 1 10 parts by mass Adhesion-enhancing agent 1: 0.2 parts by mass Hydrophilicity-imparting agent 1: 1 part by mass Ethanol 88.8 parts by mass

[0056] First, the hydrophilic antifouling agent 1 prepared above was applied in a cross pattern onto the substrate layer made of substrate 1 using a microfiber cloth, and then dried and cured by standing at 25°C for 5 minutes. Then, the surface of the layer consisting of the dried and hardened hydrophilic antifouling material 1 was wiped with a microfiber cloth. Next, the hydrophilicity enhancing agent 1 was applied to the surface of the layer made of the hydrophilic antifouling material 1, which had been wiped with water, using a microfiber cloth to enhance its hydrophilicity, and then left to stand at 25°C for 5 minutes. Then, the surface to which the hydrophilicity-enhancing treatment agent 1 was applied was wiped with water using a microfiber cloth to obtain a hydrophilic and antifouling laminate having a surface-treated hydrophilic and antifouling layer. Various evaluations were then performed on the hydrophilic, antifouling laminate obtained in this manner.

[0057] [Examples 2-11, Comparative Examples 1-7] Each hydrophilic antifouling material was obtained by stirring according to the formulations in Table 3, in the same manner as in Example 1. Then, using the hydrophilicity-enhancing treatment agent selected according to the formulation in Table 3, a hydrophilic antifouling laminate was obtained by the same procedure as in Example 1 and evaluated in the same manner.

[0058] <Evaluation Method> [Molecular weight measurement] The weight-average molecular weight of alkyl silicate resins, on a polystyrene basis, was measured using a GPC instrument (HLC-8320GPC manufactured by Tosoh Corporation).

[0059] [viscosity] Viscosity was measured using a viscometer TVB-10M (manufactured by Toki Sangyo Co., Ltd.) in accordance with JIS Z8803.

[0060] [Hydrophilic stain-resistant layer thickness] The thickness of the hydrophilic antifouling layer was measured using a reflectance spectrometer, FR-pOrtable (manufactured by ThetaMetrisis).

[0061] [Exterior view of the hydrophilic fouling prevention layer] Black tape was attached to the back surface of the substrate layer made of substrate 1, and sunlight was shone on it. The presence and degree of any abnormalities in the hydrophilic antifouling layer, as well as the presence or absence of interference colors, were observed visually. The meanings of the symbols in the table are as follows: ○: Uniform and transparent appearance △: Slight unevenness or interference coloration present. ×: Severe abnormalities such as unevenness or interference coloration.

[0062] [Contact angle] The contact angle of the hydrophilic antifouling layer surface to water was measured using a contact angle meter PCA-11 (manufactured by Kyowa Interface Science Co., Ltd.) in accordance with JIS R3257. Contact angle measurements were taken immediately after the formation of the hydrophilic antifouling layer, after 8 hours of immersion in deionized water followed by 10 cycles of drying at 80°C for 16 hours, and after 90 days of outdoor exposure.

[0063] [Table 3]

[0064] <Summary of Evaluation Results> All examples exhibited excellent appearance and low contact angles (high hydrophilicity) under each condition. However, all the comparative examples showed inferior results in at least one of them. [Industrial applicability]

[0065] The method for forming a hydrophilic antifouling layer and the hydrophilic antifouling composition of the present invention do not use hydrofluoric acid or fluorine-based solvents, resulting in a low environmental impact, excellent manufacturability, and a simple layer structure that allows for the formation of hydrophilic antifouling layers and hydrophilic antifouling laminates with an excellent balance of hydrophilicity and antifouling properties. Therefore, they are extremely useful industrially from both a performance and environmental perspective. [Explanation of symbols]

[0066] 1 Hydrophilic antifouling laminate 2 Base material layer 3 Hydrophilic antifouling layer 4. Hydrophilicity-enhancing treated surface

Claims

1. A method for forming a hydrophilic antifouling layer, comprising: forming a hydrophilic antifouling layer on a substrate layer by applying a hydrophilic antifouling material; and forming a hydrophilic-enhancing surface on the surface of the hydrophilic antifouling layer by applying a hydrophilicity-enhancing treatment agent; The surface of the substrate layer on which the hydrophilic antifouling layer is formed is made of organic and / or inorganic materials. The hydrophilic antifouling material consists of a hydrophilic antifouling composition. The hydrophilic antifouling composition contains an alkyl silicate resin (A) and a solvent (B), does not contain fine particles with a particle size of 5 nm or larger, and has a viscosity of 0.5 to 1000 mPa·s. Alkyl silicate resin (A) has alkoxysilyl groups and a weight-average molecular weight of 1,000 to 100,000. The content of alkyl silicate resin (A) in the hydrophilic antifouling composition is 0.01 to 10% by mass. The thickness of the hydrophilic antifouling layer is 10 nm or more and 1000 nm or less. The hydrophilicity-enhancing treatment agent contains an oxidizing agent (F) and a solvent (I), The oxidizing agent (F) contains hydrogen peroxide, The hydrogen peroxide content in the hydrophilicity-enhancing treatment agent is 0.01 to 5% by mass. The contact angle of the surface immediately after surface treatment of the hydrophilicity-enhancing treated surface is 1 degree or more and less than 40 degrees. A method for forming a hydrophilic antifouling layer.

2. The hydrophilic antifouling composition further contains an adhesion agent (C) and / or a hydrophilic agent (D), Adhesion-enhancing agent (C) contains a silicone-modified acrylic polymer, The hydrophilicity-imparting agent (D) contains a compound having a sulfonic acid group, The content of the adhesion-imparting agent (C) in the hydrophilic antifouling composition is 0% by mass, or 0.01 to 1% by mass. The content of the hydrophilicity imparting agent (D) in the hydrophilic antifouling composition is 0% by mass, or 0.01 to 10% by mass. A method for forming a hydrophilic antifouling layer according to claim 1.

3. The hydrophilicity-enhancing agent further contains an alkyl silicate resin (E) and a basic compound (G) and / or a hydrophilicity-imparting agent (H), and does not contain fine particles with a particle size of 5 nm or larger. The pH of the hydrophilicity-enhancing treatment agent is 8 to 11. Alkyl silicate resin (E) has an alkoxysilyl group and a weight-average molecular weight of 1,000 to 100,000. The hydrophilicity-imparting agent (H) contains one or more selected from the group consisting of an acrylic polymer having a sulfonic acid group, a sulfonic acid-modified silicate, and sodium sulfosuccinate. The content of alkyl silicate resin (E) in the hydrophilicity-enhancing treatment agent is 0.01 to 5% by mass. The content of the basic compound (G) in the hydrophilicity-enhancing treatment agent is 0% by mass, or 0.01 to 5% by mass. The content of the hydrophilicity-enhancing agent (H) in the hydrophilicity-enhancing treatment agent is 0% by mass, or 0.01 to 5% by mass. A method for forming a hydrophilic antifouling layer according to claim 1.

4. The method for forming a hydrophilic antifouling layer according to claim 1, comprising the following steps 1 to 5 in this order. Step 1: Applying a hydrophilic antifouling agent to the substrate layer. Step 2: Drying and curing the applied hydrophilic antifouling agent. Step 3: Applying a hydrophilicity-enhancing treatment agent. Step 4: Drying the applied hydrophilicity-enhancing treatment agent. Step 5: Wipe the hydrophilic treated surface with water.

5. The method for forming a hydrophilic antifouling layer according to claim 4, wherein the hydrophilic antifouling material of step 1 and / or the hydrophilicity enhancing treatment agent of step 3 are applied in a cross-coat.

6. The method for forming a hydrophilic antifouling layer according to claim 4, wherein the hydrophilic antifouling material in step 2 is dried and cured at 10 to 40°C for 1 to 60 minutes.

7. The method for forming a hydrophilic antifouling layer according to claim 4, wherein the hydrophilicity-enhancing treatment agent in step 4 is dried at 10 to 40°C for 1 to 60 minutes.

8. A hydrophilic antifouling laminate having a base layer and a hydrophilic antifouling layer adjacent to the base layer, The surface of the substrate layer facing the hydrophilic antifouling layer is made of organic and / or inorganic materials. The hydrophilic antifouling layer is the surface layer of the hydrophilic antifouling laminate, and is a layer formed by the method for forming a hydrophilic antifouling layer described in any one of claims 1 to 7, and does not exhibit interference colors and is colorless and transparent. The thickness of the hydrophilic antifouling layer is 10 nm or more and 1000 nm or less. The contact angle of the surface of the hydrophilic-enhancing treated surface of the hydrophilic antifouling layer immediately after surface treatment is 1 degree or more and less than 40 degrees. Hydrophilic antifouling laminate.

9. A hydrophilic antifouling composition that is applied, dried, and cured adjacent to a surface made of organic and / or inorganic materials of a substrate layer, The hydrophilic antifouling composition contains an alkyl silicate resin (A) and a solvent (B), and does not contain fine particles with a particle size of 5 nm or larger. Alkyl silicate resin (A) has alkoxysilyl groups and a weight-average molecular weight of 1,000 to 100,000. The content of alkyl silicate resin (A) in the hydrophilic antifouling composition is 0.01 to 10% by mass. The viscosity of the hydrophilic antifouling composition is 0.5 to 1000 mPa·s. Hydrophilic antifouling composition.

10. The hydrophilic antifouling composition further contains an adhesion agent (C) and / or a hydrophilic agent (D), Adhesion-enhancing agent (C) contains a silicone-modified acrylic polymer, The hydrophilicity-imparting agent (D) contains a compound having a sulfonic acid group, The content of the adhesion-imparting agent (C) in the hydrophilic antifouling composition is 0% by mass, or 0.01 to 1% by mass. The content of the hydrophilicity imparting agent (D) in the hydrophilic antifouling composition is 0% by mass, or 0.01 to 10% by mass. The hydrophilic antifouling composition according to claim 9.

11. A hydrophilic antifouling laminate having a base layer and a hydrophilic antifouling layer adjacent to the base layer, The surface of the substrate layer facing the hydrophilic antifouling layer is made of organic and / or inorganic materials. The hydrophilic antifouling layer is the surface layer of the hydrophilic antifouling laminate and consists of the hydrophilic antifouling composition described in claim 9 or 10, and has a thickness of 10 nm or more and 1 μm or less. The surface of the hydrophilic antifouling layer is a hydrophilic-enhancing treated surface, and the contact angle immediately after surface treatment is 1 degree or more and less than 40 degrees. The hydrophilicity-enhancing treatment agent contains an alkyl silicate resin (E), an oxidizing agent (F), a basic compound (G) and / or a hydrophilicity-imparting agent (H), and a solvent (I), has a viscosity of 0.5 to 1000 mPa·s, a pH of 8 to 11, and does not contain fine particles with a particle size of 5 nm or larger. The content of the oxidizing agent (F) in the hydrophilicity-enhancing treatment agent is 0.01 to 5% by mass. Alkyl silicate resin (E) has an alkoxysilyl group and a weight-average molecular weight of 1,000 to 100,000. The oxidizing agent (F) contains hydrogen peroxide, The hydrophilicity-imparting agent (H) contains one or more selected from the group consisting of an acrylic polymer having a sulfonic acid group, a sulfonic acid-modified silicate, and sodium sulfosuccinate. The content of the hydrophilicity-enhancing agent (E) in the hydrophilicity-enhancing treatment agent is 0.01 to 5% by mass. The content of the basic compound (G) in the hydrophilicity-enhancing treatment agent is 0% by mass, or 0.01 to 5% by mass. The content of the hydrophilicity-enhancing agent (H) in the hydrophilicity-enhancing treatment agent is 0% by mass, or 0.01 to 5% by mass. Hydrophilic antifouling laminate.

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