JP2023124881A - Anti-fogging coating agent having antiviral properties - Google Patents

Abstract

To provide an anti-fogging coating agent having both of high anti-fogging properties and improved antiviral properties.SOLUTION: Provided herein is an anti-fogging coating agent having antiviral properties, the anti-fogging coating agent including (A) ammonium ion-free elongated colloidal silicas, (B) ammonium ion-bearing spherical colloidal silicas, (C) a silane derivative compound including a polyethylene glycol chain in each molecule, and (D) a silane derivative compound including an epoxy group in each molecule (excluding the (C) silane derivative compound).SELECTED DRAWING: None

Description

The present invention relates to an anti-fog coating agent having antiviral properties.

An anti-fog coating agent is a coating liquid that can prevent fogging on the surface of an article by forming an anti-fog film by coating it on the surface of the article, such as camera lenses, face shields, glasses, etc. Applied to various products.

Various types of such antifogging coating agents have been proposed so far. For example, a coating composition that imparts antireflective and antifogging properties to a substrate having a surface to which the coating composition is applied, the coating composition comprising a porous inorganic metal oxide, at least one hydrophobic group and at least one hydrophilic group. A coating composition containing a surfactant containing an anionic group is known (Patent Document 1).

Furthermore, an antifogging agent composition comprising a specific copolymer (A), a polyfunctional block isocyanate compound (B), and a surfactant (C) has been proposed (Patent Document 2).

Further, an antifogging coating composition is known that includes a colloidal silica mixture containing acidic long colloidal silica and pH-adjusting long colloidal silica (Patent Document 3).

In addition, an anti-fog paint containing elongated colloidal silica and a silane derivative compound mixture containing at least a silane derivative compound having a polyethylene glycol chain in the molecule and a silane derivative compound having an epoxy group in the molecule. A composition has been proposed (Patent Document 4).

JP2010-131651 JP2016-169287 JP2019-19253 International publication WO2021/141044

By the way, recently, with increasing interest in preventive measures against viral diseases such as the new coronavirus infection (COVID-19), it has become necessary to add antiviral properties to antifogging agents. ing.

In this regard, the above-mentioned conventional technology provides the desired antifogging properties, but if even higher antiviral properties can be imparted, it is expected to be applied to a wider range of uses.

Therefore, the main object of the present invention is to provide an antifogging coating agent that has both high antifogging properties and superior antiviral properties.

As a result of extensive research in view of the problems of the prior art, the present inventor discovered that a composition containing a specific component has both antifogging and antiviral properties, and has completed the present invention. Ta.

That is, the present invention relates to the following antifogging coating agent.
1. An anti-fog coating agent having antiviral properties,
(A) long colloidal silica without ammonium ions;
(B) spherical colloidal silica having ammonium ions;
(C) A silane derivative compound having a polyethylene glycol chain in the molecule, and (D) a silane derivative compound having an epoxy group in the molecule (excluding the silane derivative compound mentioned in (C) above).
An anti-fog coating agent characterized by containing.
2. Item 1 above, wherein the content of spherical colloidal silica having ammonium ions is 20 to 50 parts by weight out of a total of 100 parts by weight of elongated colloidal silica without ammonium ions and spherical colloidal silica having ammonium ions. Anti-fog coating agent as described.
3. As solid content,
(A) Long colloidal silica without ammonium ions: 45 to 75% by weight,
(B) Spherical colloidal silica having ammonium ions: 20 to 45% by weight,
(C) Silane derivative compound having a polyethylene glycol chain in the molecule: 0.1 to 5% by weight,
(D) Silane derivative compound having an epoxy group in the molecule: 0.1 to 5% by weight
The anti-fog coating agent according to item 1 or 2 above.
4. 4. The antifogging coating agent according to any one of items 1 to 3 above, which contains at least one of water and a water-soluble organic solvent and is liquid in nature.
5. 5. The antifogging coating agent according to any one of items 1 to 4 above, further comprising a surfactant.
6. 6. The antifogging coating agent according to any one of items 1 to 5 above, further comprising at least one solid particle of copper and its compounds (excluding monovalent copper compounds).
7. An anti-fog/anti-virus coating film comprising a coating film of the anti-fog coating agent according to any one of items 1 to 6 above.
8. An article in which the antifogging/antiviral coating film according to item 7 is laminated on the surface of a base material.

According to the present invention, it is possible to provide an antifogging coating agent that has both high antifogging properties and superior antiviral properties.

With the antifogging coating agent of the present invention, an antifogging/antiviral coating film can be suitably formed. In this coating film, by using highly hydrophilic inorganic fine particles (spherical silica, elongated silica) as the main component, it is possible to form a coating film with high water wettability even though there are few components that elute into water. It can exhibit excellent anti-fog properties. At the same time, by imparting the property of easily drawing water into the coating film, it is possible to increase the probability of contact between the ammonium ions possessed by colloidal silica and viruses, thereby stably exhibiting antiviral properties.

1. Anti-fog coating agent The anti-fog coating agent of the present invention (coating agent of the present invention) is an anti-fog coating agent having antiviral properties,
(A) long colloidal silica without ammonium ions (component A),
(B) spherical colloidal silica having ammonium ions (component B),
(C) A silane derivative compound having a polyethylene glycol chain in the molecule (component C), and (D) a silane derivative compound having an epoxy group in the molecule (excluding the silane derivative compound in (C) above) (D component)
It is characterized by including.

(1) About each component (1-1) Component A The long colloidal silica without ammonium ions, which is the component A, is the long colloidal silica (SiO ₂ or its hydrate) is dispersed in water. The diameter (average primary particle size) of the silica primary particles is usually about 5 to 300 nm, although it is not limited. In the present invention, elongated colloidal silica can be spread and adsorbed onto the surface of a base material to form a film, and therefore can be suitably used as a component of an anti-fog coating agent.

Examples of the elongated colloidal silica include chain colloidal silica, pearl necklace-like colloidal silica, and the like.

Note that colloidal silica using water as a dispersion medium includes various types of acidic, neutral, and basic colloidal silica. In the present invention, any of them can be used, but in particular, acidic long colloidal silica exhibits strong acidity with a pH of 1 to 3 when dispersed in water, and weakly acidic to neutral to weakly basic with a pH of 4 to 9. Examples include neutral long colloidal silica and basic long colloidal silica having a pH of 10 to 14, and these can be used alone or in combination.

In this case, when using a mixture of multiple colloidal silicas, the coating agent of the present invention should be used within a range that does not affect the substrate to which the coating agent is applied (usually a weakly acidic to weakly basic range, particularly a pH range of about 7 to 10). ) It is preferable to use them in combination. For example, in addition to the combination of acidic long colloidal silica and basic long colloidal silica, the combination of basic long colloidal silica and acidic long colloidal silica, neutral long colloidal silica alone can be used. It can also be used.

Further, in the present invention, the elongated colloidal silica may be any type as long as it does not contain ammonium ions, and any type of colloidal silica can be used as long as it does not contain ammonium ions.

As such long colloidal silica itself, publicly known or commercially available ones can be used. Commercially available products include, for example, product names "ST-OUP", "ST-UP", "ST-PS-S", "ST-PS-M", "ST-PS-SO", "ST-PS-MO". ” (all manufactured by Nissan Chemical Industries, Ltd.), etc. can be used.

The solid content of component A in the coating agent of the present invention can be set appropriately depending on the desired performance, application, application site, etc., but is usually about 45 to 75% by weight, particularly 50 to 70% by weight. It is preferable.

(1-2) Component B The spherical colloidal silica having ammonium ions, which is the B component, is a colloidal solution in which spherical silica (SiO ₂ or its hydrate) is dispersed in water. For this purpose, what is known as an NH ₄ ⁺ stable alkaline (basic) sol can be used. In addition to being stabilized by ammonium ions, such spherical colloidal silica can also contribute to antiviral properties.

The spherical colloidal silica has a generally spherical particle shape in water. The diameter (average particle size) of the silica primary particles is usually about 5 to 300 nm, although it is not limited. In the present invention, two or more types of spherical colloidal silica having different average particle sizes can also be used. As a result, a denser coating film can be formed, and as a result, the elution of coating film components can be inhibited, and the occurrence of "water drip marks" as shown in Test Example 1 described later can be effectively suppressed or prevented.

Generally, spherical colloidal silica can be acidic, neutral, or basic, but in the present invention, as described above, basic spherical colloidal silica has ammonium ions and usually has a pH of 10 to 14. It is. These can be used alone or in combination.

As such spherical colloidal silica, known or commercially available ones can be used. As commercially available products, for example, product names such as "ST-N", "ST-NS", and "ST-N-40" (all manufactured by Nissan Chemical Industries, Ltd.) can be used.

The solid content of component B in the coating agent of the present invention can be appropriately set depending on the desired performance, application, application site, etc., but is usually about 20 to 50% by weight, particularly 25 to 40% by weight. It is preferable.

Although the ratio of component A and component B is not limited, the ratio of component B is preferably 20 to 50 parts by weight, and preferably 25 to 40 parts by weight, assuming the total of both is 100 parts by weight. is more preferable. This makes it possible to obtain higher antiviral properties as well as better film-forming properties, antifogging durability (water drip resistance), and the like.

(1-3) Component C As the component C, a silane derivative compound having a polyethylene glycol chain in the molecule is used. Specifically, at least one compound represented by the following general formulas (1-1) to (1-3) can be mentioned.

As a compound represented by general formula (1-1),
(In the formula, R ¹ , R ² and R ³ are the same or different and are an alkyl group having 1 to 3 carbon atoms, R ⁴ is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and n is m is an integer of 1 to 5, m is an integer of 1 to 20, preferably 4 to 20, more preferably 4 to 15).

The silane derivative compound represented by the general formula (1-1) contains an alkoxy group (i.e., -OR ¹ , -OR ² and -OR ³ groups) that can react with elongated silica and spherical silica, and water. It has a hydrophilic group (-OCH ₂ CH ₂ -) containing a polyethylene glycol chain that has high affinity with. Since the silane derivative compound represented by the general formula (1-1) has a substituent and a hydrophilic group that can react with elongated silica, the silane derivative compound has a hydrophilic group and a substituent that can react with elongated silica. It is possible to bond to silica and impart hydrophilicity to the coating film formed by the coating agent of the present invention.

Specific examples of the silane derivative compound represented by the general formula (1-1) include polyethylene glycol-modified alkoxysilanes such as methoxyPEG-10propyltrimethoxysilane and ethoxyPEG-10propyltrimethoxysilane. In addition, for example, 2-[hydroxy(polyethyleneoxy)ethyl]trimethoxysilane, 3-[hydroxy(polyethyleneoxy)propyl]trimethoxysilane, 4-[hydroxy(polyethyleneoxy)butyl]trimethoxysilane, 2-[ Alkoxy(polyethyleneoxy)ethyl]trimethoxysilane, 3-[alkoxy(polyethyleneoxy)propyl]trimethoxysilane, 4-[alkoxy(polyethyleneoxy)butyl]trimethoxysilane, etc. can also be used.

As the silane derivative compound represented by the general formula (1-1), commercially available products can also be used. As commercially available products, for example, the product names "Dynasylan 4148", "Dynasylan 4150" (all manufactured by Evonik Japan Co., Ltd.), "Methoxy PEG-10 Propyltrimethoxysilane" (PG series) (Azumax Co., Ltd.), etc. may be used. can.

In addition, as a compound represented by general formula (1-2),
(In the formula, R ¹¹ , R ¹² , R ¹³ and R ¹⁴ are the same or different and are alkyl groups having 1 to 3 carbon atoms, and A is -O-, -NHCOO-, -OCO-, - selected from the group consisting of COO-, -OCH ₂ CH (OH) CH ₂ O-, -OCH ₂ CH ₂ CH (OH) O-, -S-, -SCO- and -COS-, and n1 is 1 to 5 (where m1 is an integer of 1 to 20, preferably 4 to 20, more preferably 4 to 15) can be used. Among the silane derivative compounds represented by the general formula (1-2), the most preferred group of A in the formula is -O-.

The silane derivative compound represented by the general formula (1-2) has an alkoxy group (i.e., -OR ¹¹ , -OR ¹² and OR ¹³ groups) that can react with elongated silica, and an affinity for water. It has a hydrophilic group (-CH ₂ CH ₂ O-) containing a high polyethylene glycol chain.

Since the silane derivative compound represented by the general formula (1-2) has a substituent and a hydrophilic group that can react with the elongated silica, the silane derivative compound is bonded to the elongated silica. At the same time, it becomes possible to impart hydrophilicity to the coating film formed by the coating agent of the present invention.

Specific examples of the silane derivative compound represented by the general formula (1-2) include 3-[acetoxy(polyethyleneoxy)propyl]triethoxysilane, 2-[acetoxy(polyethyleneoxy)ethyl]trimethoxysilane, 3-[ Examples include acetoxy(polyethyleneoxy)propyl]trimethoxysilane, 4-[acetoxy(polyethyleneoxy)butyl]trimethoxysilane, and the like.

As the silane derivative compound represented by the general formula (1-2), known or commercially available compounds can be used. As a commercially available product, 3-[acetoxy(polyethyleneoxy)propyl]triethoxysilane (Gelest Inc.), which is a silane derivative compound having a polyethylene glycol chain and an acyl group in the molecule, can also be used.

As a compound represented by general formula (1-3),
(In the formula, R ²¹ , R ²² and R ²³ are the same or different from each other and are an alkyl group having 1 to 3 carbon atoms, R ²⁴ is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and B is -NHCOO-, -OCO-, -COO-, -OCH ₂ CH(OH)CH ₂ O-, -OCH ₂ CH ₂ CH(OH)O-, -S-, -SCO- and -COS- n2 is an integer of 1 to 5, and m2 is an integer of 1 to 20, preferably 4 to 20, more preferably 4 to 15. Among the silane derivative compounds represented by the general formula (1-3), the most preferred group for B in the formula is -NHCOO- (urethane group).

The silane derivative compound represented by the general formula (1-3) has an alkoxy group (i.e., -OR ²¹ , -OR ²² and -OR ²³ groups) that can react with elongated silica, and an affinity for water. It has a hydrophilic group (-CH ₂ CH ₂ O-) containing a polyethylene glycol chain with high properties.

Since the silane derivative compound represented by the general formula (1-3) has a substituent and a hydrophilic group that can react with the elongated silica, the silane derivative compound is bonded to the elongated silica. At the same time, it becomes possible to impart hydrophilicity to the coating film formed by the coating agent of the present invention.

Specific examples of the silane derivative compound represented by the general formula (1-3) include 2-hydroxy(polyethyleneoxy)ethyl[3-(trimethoxysilyl)propyl]carbamate, 2-hydroxy(polyethyleneoxy)ethyl[3- (triethoxysilyl)propyl]carbamate, 2-alkoxy(polyethyleneoxy)ethyl[3-(trimethoxysilyl)propyl]carbamate, 2-alkoxy(polyethyleneoxy)ethyl[3-(triethoxysilyl)propyl]carbamate, 2 -alkoxy(polyethyleneoxy)ethyl [4-(trimethoxysilyl)butanoic acid] ester and the like.

Furthermore, among the silane derivative compounds represented by the general formula (1-3), silane derivative compounds having a polyethylene glycol chain and a urethane group in the molecule are most preferred. A silane derivative compound having a polyethylene glycol chain and a urethane group in the molecule is produced by reacting an alkoxysilane compound having an isocyanato group, such as isocyanatopropyltrimethoxysilane or isocyanatopropyltriethoxysilane, with polyethylene glycol. Can be synthesized.

In this specification, among the silane derivative compounds represented by the general formula (1-3), a silane derivative compound having a polyethylene glycol chain and a urethane group in the molecule, which can be particularly preferably used in the embodiment, is referred to as " Sometimes called urethane silane. In addition, the silane derivative compounds represented by the general formulas (1-1), (1-2), and (1-3), respectively, are collectively referred to as "silane derivative compounds having a polyethylene glycol chain in the molecule." There is.

The solid content of component C in the coating agent of the present invention can be appropriately set depending on the desired performance, application, application site, etc., but is usually about 0.1 to 5% by weight, particularly 1 to 4% by weight. It is preferable that

(1-4) Component D As component D, a silane derivative compound having an epoxy group in the molecule (excluding the silane derivative compound (C) above) is used. As component D, a silane derivative compound represented by general formula (2) can be used.
(In the formula, R ⁵ , R ⁶ and R ⁷ are the same or different and are an alkyl group having 1 to 3 carbon atoms, p is an integer of 1 to 5, and X is an organic group containing an epoxy group. be.)

It has an alkoxy group (i.e., -OR ⁵ , -OR ⁶ and OR ⁷ groups) that can react with elongated silica and X (where X is an organic group including an epoxy group). are doing. Here, examples of the organic group containing an epoxy group include, but are not limited to, a glycidyl group.

Since the silane derivative compound represented by the general formula (2) has a substituent that can react with the elongated silica, the silane derivative compound can crosslink between the elongated silicas. It becomes possible.

Specific examples of the silane derivative compound represented by general formula (2) include 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, and 3-glycidoxypropyltrimethoxysilane. Examples include epoxy group-containing silane derivative compounds such as sidoxypropylmethyldiethoxysilane.

Examples of silane derivative compounds having an epoxy group in the molecule include product names "Dynasylan GLYEO" (Evonik Japan Co., Ltd.), "KBM402", "KBM403", "KBE402", and "KBE403" (all produced by Shin-Etsu Chemical Co., Ltd.). ) etc. can also be used. In particular, such silane derivative compounds can react with and bond with elongated silica, crosslink between elongated silica, increase the strength of the coating film, and impart hydrophilicity to the coating film. can.

The solid content of component D in the coating agent of the present invention can be appropriately set depending on the desired performance, application, application site, etc., but is usually about 0.1 to 5% by weight, particularly 1 to 4% by weight. It is preferable that

(1-5) Copper and its compounds (E component)
In the coating agent of the present invention, at least one solid particle of copper and its compounds (excluding monovalent copper compounds) can be included as component E in order to obtain higher antiviral properties.

Metallic copper can be used as the copper. The copper compound may be anything other than monovalent copper compounds, such as divalent copper compounds such as CuO, _CuCl2 , _CuSO4 , Cu( _NO3 ) ₂ , _CuCO3 , Cu(OH) ₂ , etc. Examples include various compounds. In the present invention, it is desirable to use at least metallic copper because it can more reliably enhance antiviral properties. Commercially available products can also be used.

Copper and its compounds may be contained in the coating agent of the present invention as solid particles (powder), but some of them may be dissolved to form Cu ²⁺ ions within a range that does not impede the effects of the present invention. It's okay. The particle size of the solid particles is not particularly limited, but the average particle size is usually 1 μm or less, preferably within the range of about 1 to 500 nm.

When the E component is contained in the coating agent of the present invention, the solid content can be set appropriately depending on the type of the E component used, but it is usually about 0.1 to 10% by weight, particularly 0.5% by weight. The amount is preferably 5% by weight.

(1-6) Solvent The coating agent of the present invention may contain a solvent, if necessary. Thereby, the coating agent of the present invention can be used as a liquid coating agent. As the solvent, although not limited, at least one of water and a water-soluble organic solvent can be particularly preferably used.

Examples of water-soluble organic solvents include alcohols (methanol, ethanol, propanol, isopropanol, ethylene glycol, propylene glycol, diacetone alcohol, etc.), ethers (dimethoxyethane, tetrahydrofuran, dioxane, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, etc.) , ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol tertiary butyl ether, ethylene glycol phenyl ether, diethylene glycol monomethyl ether, ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, triethylene glycol monobutyl ether, dipropylene (glycol monomethyl ether, etc.), ketones (acetone, ethyl methyl ketone, etc.), amides (dimethylformamide, etc.), dimethyl sulfoxide (DMSO), acetonitrile, nitromethane, triethylamine, and the like. These can be used alone or in combination.

The amount of the solvent to be used may be appropriately determined depending on the coating properties, film-forming properties, etc. of the coating agent of the present invention, and for example, the solid content concentration of the coating agent of the present invention is about 5 to 90% by weight, preferably 5 Although it can be set within the range of ~50%, it is not limited to this.

(1-7) Other components In the coating agent of the present invention, additives normally contained in coating compositions (surfactants, dyes, pigments, plasticizers, dispersants, , preservatives, matting agents, antistatic agents, flame retardants, etc.) can be appropriately blended. The surfactant may be any of anionic surfactants, cationic surfactants, nonionic surfactants, and amphoteric surfactants. By adding a surfactant, the coating agent of the present invention can be applied to the substrate more smoothly.

(2) Properties of the coating agent of the present invention The coating agent of the present invention can usually be used in a liquid form. In this case, as described above, a predetermined amount of solvent can be used. When the coating agent of the present invention is a liquid, its viscosity etc. can be appropriately set depending on the use, the type of substrate, etc.

2. Production of Coating Agent of the Present Invention The coating agent of the present invention can be produced by uniformly mixing the above-mentioned components. The order of mixing is also not particularly limited, and each component may be mixed simultaneously or sequentially.

Further, the mixing can be carried out using a known or commercially available device such as a mixer or a kneader.

3. Use of the coating agent of the present invention The coating agent of the present invention can be applied to the surface of a substrate in the same way as known or commercially available anti-fog coating agents to form a coating (anti-fog/anti-virus coating) on the surface of the substrate. A cured film can be formed as a cured film. The present invention also includes anti-fogging and anti-viral coating films made of the coating agent of the present invention.

The material of the base material is not particularly limited, and may be, for example, plastics, glass, metals, ceramics, rubber, or the like. Further, the base material may be, for example, a material constituting any of raw materials, primary products, final products, etc. Examples of final products include lighting devices, headlights, windows, lenses, lens covers, monitors, monitor covers, glasses/sunglasses, goggles, face shields, face guards, helmets, and the like. In this way, the present invention also includes an article in which an antifogging/antiviral coating film made of the coating agent of the present invention is laminated on the surface of a base material constituting the article.

The article of the present invention containing an antifogging/antiviral coating film has excellent antifogging properties and excellent antiviral properties due to the coating film. Furthermore, even when the article is exposed to unexpected high temperature conditions, the formation of drip marks and the like can be effectively suppressed and a good appearance can be maintained. In addition, the coating film made of the coating agent of the present invention firmly adheres to base materials such as plastics and has high adhesion, so it has high durability under high temperatures and exhibits antifogging and antiviral properties over a long period of time. I can do it.

The method of applying the coating agent of the present invention to the substrate is not limited, and various coating methods such as a doctor blade method, bar coating method, dipping method, air spray method, roller brush method, and roller coater method may be employed. be able to.

The coating thickness is not particularly limited, but may be adjusted so that the thickness of the finally formed antifogging/antiviral coating is within the range of about 0.1 to 10 μm, but is not limited thereto.

After application, the antifogging/antiviral coating can be formed as a cured film by drying the coating. The drying may be carried out naturally, but preferably by heating. The temperature during heat drying may be set to a temperature sufficient to cause the silica and the silane derivative to react and to evaporate water (and the organic solvent if contained). The heating temperature can be, for example, about 80 to 150°C, particularly 100 to 140°C. Thereby, the reaction can proceed smoothly and water and the organic solvent can be evaporated.

The heating means is not particularly limited, and for example, in addition to heating using a heating device such as a burner or an oven, heating can be performed using a heating method using hot air such as a dryer. In this way, when the coating film formed by the coating agent of the present invention dries, the elongated colloidal silica (and in some cases spherical colloidal silica) spread on the surface of the substrate becomes elongated silica (in some cases spherical colloidal silica). Then, a predetermined cured film is formed. On the other hand, the silane derivative compound combines with these silicas, crosslinks between the silicas, and forms a strong higher-order structure. In this manner, by applying the coating agent of the present invention to an article, an antifogging/antiviral coating film can be formed, and as a result, an article coated with such a coating film can be obtained.

The article according to the present invention has excellent anti-fogging properties due to its coating film as well as excellent anti-viral properties. Moreover, as mentioned above, when two types of spherical colloidal silica with different particle sizes are used together, even if the article is exposed to unexpected high temperature conditions, the appearance such as the formation of drip marks can be avoided. Changes can be effectively suppressed. In addition, the coating film made of the coating agent of the present invention firmly adheres to base materials such as plastics and has high adhesion, so it has high durability under high temperatures and maintains anti-fog and anti-virus properties over a long period of time. I can do it.

Examples and comparative examples will be shown below to explain the features of the present invention more specifically. However, the scope of the present invention is not limited to the examples.

Examples 1 to 3
A coating agent was prepared by uniformly mixing each component shown in Table 1. Note that the unit of content of each component is "% by weight".

Comparative example 1
A coating agent was prepared in the same manner as in Example 1, except that the composition was changed to that shown in Table 1.

The meanings of the abbreviations in Table 1 are as follows.
・"ST-OUP": Snowtex OUP, Nissan Chemical Industries, Ltd., acidic long colloidal silica (solid content 15% by weight, water dispersion)
・"ST-UP": Snowtex UP, Nissan Chemical Industries, Ltd., Na ⁺ -containing basic long colloidal silica (solid content 20% by weight, water dispersion)
・"ST-N": Snowtex N, Nissan Chemical Industries, Ltd., NH ₄ ⁺ containing spherical basic colloidal silica with a particle size of 12 nm (solid content 20% by weight, water dispersion)
・"ST-NXS": Snowtex NXS, Nissan Chemical Industries, Ltd., basic spherical colloidal silica containing NH ₄ ⁺ with a particle size of 5 nm (solid content 15% by weight, water dispersion)
・"FT-150": Ftergent 150, Neos Co., Ltd., anionic surfactant (solid content 100% by weight)
・"D-4148": Dynasilan 4148, Evonik Japan Co., Ltd., silane derivative compound having a polyethylene glycol chain in the molecule (solid content 100% by weight)
・"KBM-403": Shin-Etsu Chemical Co., Ltd., silane derivative compound having an epoxy group in the molecule (solid content 100% by weight)
・“PGM”: Propylene glycol monomethyl ether ・Copper powder: Copper powder “CP-250” manufactured by Aintech (average particle size 250 nm)

Test example 1
A coating film was formed using the coating agent prepared in each Example and Comparative Example to prepare a sample. Each coating agent was applied onto a PET film (Toyobo Co., Ltd. "Cosmoshine A4100", thickness 100 μm). The coating was performed by bar coating, and the coating amount was adjusted so that the thickness of the coating film (cured film) after the coating agent was cured was 1 μm. The PET film coated with the coating agent was placed in an oven at 110°C and heated for 15 minutes to form a coating film to obtain a sample. Using the obtained samples, various performance evaluations were performed using the methods shown below.

(1) Transparency Measured using a haze meter according to Japanese Industrial Standard JIS K7136. When the haze value was less than 1.0, it was written as "○", and when the haze value was 1.0 or more, it was written as "x".

(2) Antifogging property The sample was placed at a height of 1 cm from the water surface of a 40° C. hot water bath with the coating film facing downward, and the coating film was exposed to steam from the hot water bath for 10 seconds. During this time, it was visually confirmed whether or not clouding was formed on the coating film.

(3) Water drip marks The sample subjected to the anti-fogging evaluation in (2) above was kept standing vertically for 30 minutes to dry, and visually inspected to see if any water drip marks were formed on the sample surface. Confirmed by.

(4) Antiviral properties Measured by the plaque measurement method of ISO21072:2019. As test viruses, a) influenza virus and b) feline calicivirus were used, and the virus infectivity titer was measured 24 hours later. The difference in virus infectivity with the blank film (PET film) was defined as the antiviral activity value. If the antiviral activity value is 2.0 or more, mark it as "◎"; if the antiviral activity value is less than 2.0 or more than 1.5, mark it as "○"; if the antiviral activity value is less than 1.5, mark it as "○". I marked it with an “×”.
The outline of the antiviral test conditions for each of a) and b) above is as shown below.
a) Influenza virus/test virus: Influenza A virus (H3N2, A/Hong Kong/8/68)
・Host cells: MDCK cells (canine kidney-derived cell line)
・Reaction conditions: 25℃, 24 hours ・Washing solution: SCDLP medium b) Feline calicivirus ・Test virus: Feline calicivirus (F-9)
・Host cell: CRFK cell (feline kidney-derived cell line)
・Reaction conditions: 25℃, 30 minutes ・Washing solution: SCDLP medium

As is clear from the results in Table 1, Examples 1 to 3 exhibit excellent antifogging properties and excellent antiviral properties. This is considered to be an effect obtained by blending colloidal silica having ammonium ions as a main component. In particular, it can be seen that Example 1 containing copper powder can exhibit higher antiviral properties.
In addition, although Example 3 can exhibit excellent anti-fogging and anti-viral properties, the combination of two types of spherical colloidal silica with different particle sizes as shown in Examples 1 and 2 results in the formation of drip marks. It can be seen that this can be effectively suppressed.

The coating agent of the present invention can suitably form an antifogging/antiviral coating film by applying it to the surface of a substrate. As a result, various products that have anti-fog and anti-virus properties (lighting devices, headlights, windows, lenses, lens covers, monitors, monitor covers, glasses/sunglasses, goggles, face shields, face guards, helmets) It becomes possible to provide

Claims (8)

An anti-fog coating agent having antiviral properties,
(A) long colloidal silica without ammonium ions;
(B) spherical colloidal silica having ammonium ions;
(C) A silane derivative compound having a polyethylene glycol chain in the molecule, and (D) a silane derivative compound having an epoxy group in the molecule (excluding the silane derivative compound mentioned in (C) above).
An anti-fog coating agent characterized by containing. Claim 1, wherein the content of the spherical colloidal silica having ammonium ions is 20 to 50 parts by weight out of a total of 100 parts by weight of the elongated colloidal silica without ammonium ions and the spherical colloidal silica having ammonium ions. Anti-fog coating agent as described. As solid content,
(A) Long colloidal silica without ammonium ions: 45 to 75% by weight,
(B) Spherical colloidal silica having ammonium ions: 20 to 50% by weight,
(C) Silane derivative compound having a polyethylene glycol chain in the molecule: 0.1 to 5% by weight,
(D) Silane derivative compound having an epoxy group in the molecule: 0.1 to 5% by weight
The anti-fog coating agent according to claim 1 or 2, comprising: The antifogging coating agent according to any one of claims 1 to 3, which contains at least one of water and a water-soluble organic solvent and is liquid in nature. The anti-fog coating agent according to any one of claims 1 to 4, further comprising a surfactant. The antifogging coating agent according to any one of claims 1 to 5, further comprising at least one solid particle of copper and its compounds (excluding monovalent copper compounds). An anti-fog/anti-virus coating film comprising a coating film of the anti-fog coating agent according to any one of claims 1 to 6. An article comprising the antifogging/antiviral coating film according to claim 7 laminated on the surface of a base material.