Anti-fogging agent, method for preventing fogging of vehicle lamp structure, and vehicle lamp structure

Abstract

Provided is an anti-fogging agent containing: inorganic particles; a silane coupling agent A having a reactive group X; and a compound B having a reactive group Y capable of reacting with and bonding to the reactive group X; wherein the content of the silane coupling agent A is 5 parts by mass or more with respect to 100 parts by mass of the inorganic particles, and the content of the compound B is 0.2 parts by mass or more with respect to 100 parts by mass of the inorganic particles.

Description

Anti-fogging agent, method for preventing fogging of vehicle lamp structures, and vehicle lamp structure

[0001] This disclosure relates to an anti-fogging agent, a method for preventing fogging of vehicle lamp structures, and vehicle lamp structures.

[0002] A method is known for applying an anti-fogging agent composition containing a surfactant to the lamp chamber of a vehicle lamp structure, such as an automobile, where fogging due to condensation may occur (see, for example, Patent Document 1). When moisture adheres to the anti-fogging film formed by the anti-fogging agent containing the surfactant, the effect of the surfactant causes the moisture to instantly turn into a water film, suppressing the occurrence of fogging.

[0003] Japanese Patent Publication No. 2016-027134

[0004] However, with the above-mentioned anti-fogging film, when moisture flows off the surface of the anti-fogging film, aggregated surfactants also flow off with it, which can cause streaks on the surface of the anti-fogging film. In order to form an anti-fogging film that is less prone to such streaks, the inventors investigated anti-fogging agents containing inorganic particles. However, when steam tests were conducted with anti-fogging agents containing inorganic particles, appearance defects sometimes occurred after drying following steam irradiation.

[0005] One aspect of this disclosure, made in view of the above circumstances, aims to provide an anti-fogging agent containing inorganic particles that can form an anti-fogging film less prone to appearance defects after steam testing. Another aspect of this disclosure aims to provide a method for preventing fogging of a vehicle lamp structure using the anti-fogging agent, and a vehicle lamp structure using the anti-fogging agent.

[0006] One aspect of this disclosure includes the following [1] to

[11] : [1] An antifogging agent comprising inorganic particles, a silane coupling agent A having a reactive group X, and a compound B having a reactive group Y that can react with and bond to the reactive group X, wherein the content of the silane coupling agent A is 5 parts by mass or more per 100 parts by mass of the inorganic particles, and the content of the compound B is 0.2 parts by mass or more per 100 parts by mass of the inorganic particles. [2] The antifogging agent according to [1], wherein the inorganic particles are silica. [3] The antifogging agent according to [1] or [2], wherein the content of the silane coupling agent A is 50 parts by mass or less per 100 parts by mass of the inorganic particles. [4] The antifogging agent according to any one of [1] to [3], wherein the content of the compound B is 50 parts by mass or less per 100 parts by mass of the inorganic particles. [5] The antifogging agent according to any one of [1] to [4], wherein the content of the silane coupling agent A is 50 parts by mass or more per 100 parts by mass of the compound B. [6] The antifogging agent according to any one of [1] to [5], wherein one of the reactive group X and the reactive group Y is an epoxy group, a carboxyl group, a hydroxyl group, or an acid anhydride group, and the other is an amino group, an isocyanate group, or a ureido group. [7] The antifogging agent according to any one of [1] to [6], wherein the reactive group X is an epoxy group and the reactive group Y is an amino group. [8] The antifogging agent according to any one of [1] to [7], wherein the compound B has a polyether group. [9] The antifogging agent according to any one of [1] to [8], further comprising a silane coupling agent having a polyether group.

[10] A method for preventing fogging of a vehicle lamp structure, comprising the steps of: applying the antifogging agent according to any one of [1] to [9] to the inner surface of a lens provided by the vehicle lamp structure to form a coating film; and drying the coating film.

[11] A vehicle lamp structure comprising an antifogging film formed from the antifogging agent according to any one of [1] to [9] on the inner surface of the lens.

[0007] According to one aspect of the present disclosure, it is possible to provide an anti-fogging agent containing inorganic particles, which can form an anti-fogging film that is less likely to develop appearance defects after a steam test. Further, according to another aspect of the present disclosure, it is possible to provide an anti-fogging method for a vehicle lamp structure using the anti-fogging agent, and a vehicle lamp structure using the anti-fogging agent.

[0008] FIG. 1 is a diagram schematically showing a vehicle lamp structure.

[0009] Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the drawings as appropriate. However, the present disclosure is not limited to the following embodiments. In addition, the materials exemplified below may be used alone or in combination of two or more, unless otherwise specified. The content of each component in the composition means the total amount of the plurality of substances corresponding to each component in the composition, unless otherwise specified, when there are a plurality of substances corresponding to each component in the composition. The numerical range indicated by "~" indicates a range including the numerical values described before and after "~" as the minimum value and the maximum value, respectively. In the numerical ranges described stepwise in this specification, the upper limit value or the lower limit value of a certain step's numerical range may be replaced with the upper limit value or the lower limit value of another step's numerical range. In the numerical ranges described in this specification, the upper limit value or the lower limit value of the numerical range may be replaced with the value shown in the examples.

[0010] <Anti-fogging agent> The anti-fogging agent of the present embodiment contains inorganic particles, a silane coupling agent A having a reactive group X, and a compound B having a reactive group Y capable of reacting and bonding with the reactive group X. The content of the silane coupling agent A is 5 parts by mass or more with respect to 100 parts by mass of the inorganic particles, and the content of the compound B is 0.2 parts by mass or more with respect to 100 parts by mass of the inorganic particles. According to the anti-fogging agent of the present embodiment, it is possible to form an anti-fogging film that is less likely to develop appearance defects (e.g., whitening, cracking) after a steam test.

[0011] The inventors of the present invention speculate as follows about the reason why such an effect is achieved. According to the anti-fogging agent having the above configuration, it is considered that a strong film can be formed by bonding inorganic particles with the reaction product of silane coupling agent A and compound B. Further, when a certain amount of silane coupling agent A and compound B are present with respect to the inorganic particles, a certain amount of the reaction product of silane coupling agent A and compound B can be generated, and it is considered that a strong film can be formed more reliably.

[0012] (Inorganic particles) The inorganic particles include oxides such as silica, alumina, ceria, titania, zirconia, magnesia, yttria, zinc oxide, and iron oxide; nitrides such as silicon nitride, titanium nitride, and boron nitride; and hydroxides such as cerium hydroxide. The inorganic particles may be silica (for example, colloidal silica) from the viewpoint of forming an anti-fogging film in which appearance defects are less likely to occur after a steam test.

[0013] The silica particles may contain metal oxides other than silicon dioxide. Examples of the metal oxide include alumina. Examples of such silica particles include colloidal silica in which aluminosilicate is firmly formed on the surface of colloidal silica for the stabilization of the silica sol.

[0014] The silica particles are available as a dispersion of silica particles. Examples of the dispersion medium include water, isopropyl alcohol, 1-methoxy-2-propyl alcohol, ethyl alcohol, methyl alcohol, ethylene glycol, ethylene glycol-n-propyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, dimethylacetamide, N-methylpyrrolidone, toluene, methyl ethyl ketone, methyl isobutyl ketone, cyclohexane, ethyl acetate, etc. The dispersion medium may be a mixture of the above dispersion media. The dispersion medium of the silica particles may be water from the viewpoint of versatility.

[0015] The raw material for silica particles may be water glass or alkoxysilane. When the raw material is water glass, the silica particle production process involves, for example, heating and concentrating sodium silicate using a hydrothermal synthesis method to produce silica particles. Specifically, silica particles may be produced by creating a three-dimensional network structure aggregate under an acidic pH to suppress the growth of primary particles, and then crushing it, or by creating a block-shaped aggregate under an alkaline pH to accelerate the growth of primary particles, and then crushing it. When the raw material is alkoxysilane, the silica particle production process involves, for example, producing silica particles by sol-gel synthesis of alkoxysilane. Specifically, silica particles may be produced by accelerating the hydrolysis reaction of alkoxysilane, then accelerating the polycondensation reaction to obtain a gel, and then removing the solvent by heat treatment, or by obtaining a gel and then performing solvent replacement with a predetermined solvent.

[0016] The dispersion liquid of シリカ particles is commercially available products such as いてよく, example えば, manufactured by Nissan Chemical Co., Ltd. ST-PS-SO, ST-PS- MO、ST-PS-M、ST-PS-S、ST-UP、S T-OUP, IPA-ST-UP, MA-ST-UP, P GM-ST-UP, MEK-ST-UP, IPA-ST, IPA-ST-L, IPA-ST-ZL, MA-ST-M , MA-ST-L, MA-ST-ZL, EG-ST, EG -ST-XL-30, NPC-ST-30, PGM-ST , DMAC-ST, DMAC-ST-ZL, NMP-ST , TOL-ST, MEK-ST-40, MEK-ST-L , MEK-ST-ZL, MIBK-ST, MIBK-ST -L, CHO-ST-M, EAC-ST, PMA-ST, MEK-EC-2130Y, MEK-EC-2430Z, MEK-EC-2140Z, MEK-AC-4130Z, MEK-AC-5140Z, PGM-AC-2140Y, PGM-AC-4130Y, MIBK-AC-2140Z , MIBK-SD-L, ST-XS, ST-OXS, ST -NXS, ST-CXS, ST-S, ST-OS, ST- NS, ST-30, ST-O, ST-N, ST-C, ST-AK, ST-50-T, ST-O-40, ST-N-4 0.ST-CM, ST-30L, ST-OL, ST-AK -L, ST-YL, ST-OYL, ST-AK-YL, S T-ZL, MP-1040, MP-2040, MP-4540M; PL-1-IPA, PL- made by Fuso Chemical Co., Ltd. 1-TOL, PL-2L-PGME, PL-2L-MEK, PL-2L, PL-3, PL-4, PL-5, PL-1H, PL-3H, PL-5H, BS-2L, BS-3L, BS-5L, HL-2L, HL-3L, HL-4L, PL-3-C, PL-3-D; Tama Chemical Industry Co., Ltd.'s TCSOL800; Nichiki Catalyst Chemical Co., Ltd.'s SI-40, SI-50, SI-45P, SI-80P, SIK-23, S-30H, SIK-15, SI-550 etc.

[0017] Examples of inorganic particle shapes (external shapes) include spherical, bead-like (a shape in which multiple spherical particles of approximately the same diameter are linked together), pearl necklace-like, chain-like, scale-like, needle-like, cubic, rectangular, cocoon-like, aggregate-like, and konpeito-like shapes. Furthermore, the inorganic particles may include two or more particles with different shapes from each other.

[0018] The average particle size of the inorganic particles may be 1 to 1000 nm. If the average particle size of the inorganic particles is 1 nm or more, the inorganic particles are less likely to aggregate in the anti-fogging agent, making it easier for the inorganic particles to adhere to the substrate. If the average particle size of the inorganic particles is 1000 nm or less, the specific surface area of ​​the inorganic particles increases, making it easier for the inorganic particles to adhere to the substrate. From these viewpoints, the average particle size of the inorganic particles may be 3 to 500 nm, or 5 to 200 nm.

[0019] In this specification, the average particle size of inorganic particles can be measured, for example, by the following procedure: Dilute the inorganic particles with deionized water or any solvent to obtain a diluent so that the inorganic particle content is approximately 1.0% by mass (content at which the transmittance (H) at measurement is 60-70%). Then, measure the average particle size of the inorganic particles in the diluent using dynamic light scattering (manufactured by Otsuka Electronics Co., Ltd., product name: nanoSAQLA).

[0020] From the viewpoint of superior anti-fogging properties, the inorganic particle content may be 1% by mass or more, 5% by mass or more, or 10% by mass or more, based on the total amount of solids in the anti-fogging agent. From the viewpoint of making it easier to maintain anti-fogging properties (hydrophilicity), the inorganic particle content may be 97% by mass or less, 95% by mass or less, or 90% by mass or less, based on the total amount of solids in the anti-fogging agent. From these viewpoints, the inorganic particle content may be 1 to 97% by mass, 5 to 95% by mass, or 10 to 90% by mass, based on the total amount of solids in the anti-fogging agent.

[0021] (Silane Coupling Agent A) The reactive group X of silane coupling agent A may be an epoxy group, a carboxyl group, a hydroxyl group, or an acid anhydride group, or it may be an amino group, an isocyanate group, or a ureido group. If one is an epoxy group, a carboxyl group, a hydroxyl group, or an acid anhydride group, the other may be an amino group, an isocyanate group, or a ureido group. That is, if the reactive group Y is an amino group, an isocyanate group, or a ureido group, the reactive group X may be an epoxy group, a carboxyl group, a hydroxyl group, or an acid anhydride group, and if the reactive group Y is an epoxy group, a carboxyl group, a hydroxyl group, or an acid anhydride group, the reactive group X may be an amino group, an isocyanate group, or a ureido group. From the viewpoint of being able to form an anti-fogging film that is less likely to cause appearance defects after steam testing, the reactive group X may be an epoxy group.

[0022] Silane coupling agent A may have multiple reactive groups X. If silane coupling agent A has multiple reactive groups X, each reactive group X may be the same or different.

[0023] Examples of silane coupling agents having an epoxy group include 3-glycidyloxypropyltrimethoxysilane (KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.), 8-glycidoxyoctyltrimethoxysilane (KBM-4803, manufactured by Shin-Etsu Chemical Co., Ltd.), 3-glycidyloxypropyltriethoxysilane (KBE-403, manufactured by Shin-Etsu Chemical Co., Ltd.), KBE-402, X-12-981S, and X-12-984S (all are trade names, manufactured by Shin-Etsu Chemical Co., Ltd.).

[0024] Examples of silane coupling agents containing a carboxyl group include X-12-1135 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.).

[0025] Examples of silane coupling agents containing an amino group include 3-aminopropyltrimethoxysilane (KBM-903, manufactured by Shin-Etsu Chemical Co., Ltd.), 3-aminopropyltriethoxysilane (KBE-903, manufactured by Shin-Etsu Chemical Co., Ltd.), N-2-(aminoethyl)-3-aminopropyltrimethoxysilane (KBM-603, manufactured by Shin-Etsu Chemical Co., Ltd.), N-2-(aminoethyl)-8-aminooctyltrimethoxysilane (KBM-6803, manufactured by Shin-Etsu Chemical Co., Ltd.), N-2-(aminoethyl)-3-aminopropyltriethoxysilane (KBE-603, manufactured by Shin-Etsu Chemical Co., Ltd.), and N-phenyl-3-aminopropyltrimethoxysilane. Examples include (KBM-573 manufactured by Shin-Etsu Chemical Co., Ltd.), N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane (KBM-602 manufactured by Shin-Etsu Chemical Co., Ltd.), N-2-(aminoethyl)-3-aminopropylmethyldiethoxysilane (KBE-602 manufactured by Shin-Etsu Chemical Co., Ltd.), N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane (KBM-575 manufactured by Shin-Etsu Chemical Co., Ltd.), 3-triethoxysilyl-N-(1,3-dimethylbutylidene)propylamine (KBE-9103P manufactured by Shin-Etsu Chemical Co., Ltd.), and X-12-972F (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.).

[0026] Silane coupling agent A may be a silane coupling agent represented by general formula (X).

[0027] [In formula (X), R １ , R ２ , and R 3 Each of these independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, s represents an integer from 1 to 10, and t represents an integer from 1 to 10.

[0028] In formula (X), R １ , R ２ , and R ３ Each of these may independently be a hydrogen atom, a methyl group, or an ethyl group. s may be an integer from 1 to 8, 1 to 5, or 1 to 3. t may be an integer from 1 to 8, 1 to 5, or 1 to 3.

[0029] The content of silane coupling agent A is 5 parts by mass or more per 100 parts by mass of inorganic particles. From the viewpoint of forming an anti-fogging film that is less likely to cause appearance defects after steam testing, the content of silane coupling agent A may be 7 parts by mass or more, 10 parts by mass or more, 12 parts by mass or more, or 15 parts by mass or more per 100 parts by mass of inorganic particles, and from the same viewpoint, it may be 70 parts by mass or less, 60 parts by mass or less, 50 parts by mass or less, 40 parts by mass or less, 30 parts by mass or less, 20 parts by mass or less, or 15 parts by mass or less. From these viewpoints, the content of silane coupling agent A may be 5 to 70 parts by mass, 5 to 50 parts by mass, 5 to 30 parts by mass, 5 to 20 parts by mass, 5 to 15 parts by mass, 7 to 20 parts by mass, 10 to 20 parts by mass, 12 to 20 parts by mass, or 15 to 20 parts by mass per 100 parts by mass of inorganic particles.

[0030] The content of silane coupling agent A may be 50 parts by mass or more, 100 parts by mass or more, 150 parts by mass or more, 200 parts by mass or more, 250 parts by mass or more, 300 parts by mass or more, 500 parts by mass or more, 600 parts by mass or more, 1000 parts by mass or more, 1200 parts by mass or more, 1500 parts by mass or more, 2000 parts by mass or more, 2500 parts by mass or more, or 3000 parts by mass or more, per 100 parts by mass of compound B. From the viewpoint of forming an anti-fogging film that is less likely to cause appearance defects after steam testing, the content may be 50 parts by mass or more, 100 parts by mass or more, 1500 parts by mass or more, 1500 parts by mass or more, 2000 parts by mass or more, 2500 parts by mass or more, or 3000 parts by mass or more. From these viewpoints, the content of silane coupling agent A may be 50 to 5000 parts by mass, 50 to 4000 parts by mass, 50 to 3500 parts by mass, 50 to 3000 parts by mass, 100 to 5000 parts by mass, 500 to 5000 parts by mass, 1000 to 5000 parts by mass, 2000 to 5000 parts by mass, 2500 to 5000 parts by mass, or 3000 to 5000 parts by mass per 100 parts by mass of compound B.

[0031] The content of the silane coupling agent A can be appropriately set according to the content of the compound B from the viewpoint of forming an anti-fogging film in which appearance defects are less likely to occur after the steam test. However, based on the total solid content of the anti-fogging agent, it may be 0.1% by mass or more, 1% by mass or more, 2% by mass or more, or even 2.5% by mass. From the same viewpoint, it may be 30% by mass or less, 20% by mass or less, 15% by mass or less, or even 10% by mass or less. From these viewpoints, the content of the silane coupling agent A may be 0.1 to 30% by mass, 1 to 20% by mass, 2 to 15% by mass, or 2.5 to 15% by mass based on the total solid content of the anti-fogging agent.

[0032] (Compound B) The reactive group Y possessed by the compound B may be an epoxy group, a carboxyl group, a hydroxy group, or an acid anhydride group, or may be an amino group, an isocyanate group, or a ureido group. When the reactive group X is an epoxy group, a carboxyl group, a hydroxy group, or an acid anhydride group, the reactive group Y may be an amino group, an isocyanate group, or a ureido group. When the reactive group X is an amino group, an isocyanate group, or a ureido group, the reactive group Y may be an epoxy group, a carboxyl group, a hydroxy group, or an acid anhydride group. In addition, when the compound B has two or more reactive groups Y, the two or more reactive groups Y may be the same or different. From the viewpoint of forming an anti-fogging film in which appearance defects are less likely to occur after the steam test, the reactive group Y may be an amino group.

[0033] The compound B may have a plurality of reactive groups Y. When the compound B has a plurality of reactive groups Y, each reactive group Y may be the same or different.

[0034] The compound B may have a polyether chain as the main chain from the viewpoint of forming an anti-fogging film in which appearance defects are less likely to occur after the steam test. The polyether chain is -(R-O) ｎ -(wherein, R is C ２ H ４ or C ３ H ６The polyether chain may also contain a group represented by (where n is an integer). Furthermore, the polyether chain may contain one or both of the structural units derived from ethylene oxide and the structural units derived from propylene oxide, and if both are included, they may be random or blocky.

[0035] From the viewpoint of providing a hydrophilic compound with a reaction site, compound B may be a polyetherdiamine compound represented by general formula (Y).

[0036] [In equation (Y), x, y, and z each represent an integer between 1 and 100.]

[0037] In equation (Y), x + z may be 6 or less and y may be 39 or less; x + z may be 4 or less and y may be 9 or less; and x + z may be 6 or less and y may be 13 or less.

[0038] From the viewpoint of forming an anti-fogging film with further improved moisture resistance, in formula (Y), x + z may be 3 to 9 and y may be 30 to 50. When a polyetherdiamine compound satisfying these conditions is incorporated, an anti-fogging film with excellent water film uniformity can be formed, and in vehicle lamp structures, the occurrence of fogging can be suppressed while maintaining sufficient straightness and intensity of transmitted light.

[0039] From the same viewpoint as above, in equation (Y), y / (x+z) may be between 3 and 8.

[0040] As compound B, commercially available products such as "ED-600," "ED-900," and "ED-2003" (manufactured by HUNTSUMAN Co., Ltd., trade names, etc.) may be used.

[0041] The content of compound B is 0.2 parts by mass or more per 100 parts by mass of inorganic particles. From the viewpoint of forming an anti-fogging film that is less likely to cause appearance defects after steam testing, the content of compound B may be 0.5 parts by mass or more, 0.8 parts by mass or more, 1.0 parts by mass or more, 1.5 parts by mass or more, 2.0 parts by mass or more, or 3.0 parts by mass or more per 100 parts by mass of inorganic particles. Similarly, from the viewpoint of forming an anti-fogging film that is less likely to cause appearance defects after steam testing, the content of compound B may be 270 parts by mass or less, 200 parts by mass or less, 150 parts by mass or less, 100 parts by mass or less, 70 parts by mass or less, 50 parts by mass or less, 40 parts by mass or less, 30 parts by mass or less, 20 parts by mass or less, 10 parts by mass or less, 8.0 parts by mass or less, 6.0 parts by mass or less, 5.0 parts by mass or less, or 4.0 parts by mass or less. From these viewpoints, the content of compound B may be 0.2 to 270 parts by mass, 0.2 to 200 parts by mass, 0.2 to 100 parts by mass, 0.2 to 50 parts by mass, 0.2 to 30 parts by mass, 0.2 to 10 parts by mass, 0.2 to 8.0 parts by mass, 0.2 to 6.0 parts by mass, 0.2 to 5.0 parts by mass, 0.2 to 4.0 parts by mass, 0.5 to 4.0 parts by mass, 0.8 to 4.0 parts by mass, 1.0 to 4.0 parts by mass, 1.5 to 4.0 parts by mass, 2.0 to 4.0 parts by mass, or 3.0 to 4.0 parts by mass per 100 parts by mass of inorganic particles.

[0042] From the viewpoint of forming an anti-fogging film that is less prone to appearance defects after steam testing, the content of compound B may be 0.01% by mass or more, 0.1% by mass or more, 0.2% by mass or more, or 0.3% by mass or more, based on the total amount of solids in the anti-fogging agent. Similarly, from the same viewpoint, it may be 30% by mass or less, 20% by mass or less, 15% by mass or less, or 10% by mass or less. From these viewpoints, the content of compound B may be 0.01 to 30% by mass, 0.1 to 20% by mass, 0.2 to 15% by mass, or 0.3 to 10% by mass, based on the total amount of solids in the anti-fogging agent.

[0043] (Compound product) The anti-fogging agent of this embodiment may further contain a compound E obtained by reacting a silane coupling agent having an acid anhydride group or an epoxy group (hereinafter, this silane coupling agent is also referred to as "silane coupling agent C") with a sorbitan compound having a hydroxyl group (hereinafter, this sorbitan compound is also referred to as "sorbitan compound D"), from the viewpoint of water resistance and moisture resistance.

[0044] [Silane coupling agent C] The silane coupling agent having an acid anhydride group may be, for example, a silane coupling agent represented by general formula (1).

[0045] [In formula (1), R 1１ , R 1２ , and R 13 Each of these independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and a represents an integer from 1 to 10.

[0046] In formula (1), R 1１ , R 1２ , and R 13 Each of these may independently be a hydrogen atom, a methyl group, an ethyl group, a propyl group, or a butyl group. a may be an integer from 1 to 8, 1 to 5, or 1 to 3.

[0047] Examples of silane coupling agents having an acid anhydride group include 3-trimethoxysilylpropyl succinic anhydride (X-12-967C, manufactured by Shin-Etsu Chemical Co., Ltd., etc.).

[0048] The silane coupling agent having an epoxy group may be, for example, a silane coupling agent represented by general formula (2) or general formula (3).

[0049] [In formula (2), R ２１ , R ２２ , and R ２3 Each of these independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and b represents an integer from 1 to 10.

[0050] [In formula (3), R ３１ , R ３２ , and R ３3 Each of these independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, c represents an integer from 1 to 10, and d represents an integer from 1 to 10.

[0051] In formula (2), R 2１ , R 2２ , and R 2３ Each of these may independently be a hydrogen atom, a methyl group, or an ethyl group. b may be an integer from 1 to 8, 1 to 5, or 1 to 3.

[0052] In formula (3), R ３１ , R ３２ , and R ３３ Each of these may independently be a hydrogen atom, a methyl group, or an ethyl group. c may be an integer from 1 to 8, 1 to 5, or 1 to 3. d may be an integer from 1 to 8, 1 to 5, or 1 to 3.

[0053] As an epoxy group-containing silane coupling agent, those listed as examples of silane coupling agent A can be used.

[0054] [Sorbitan Compound D] The anti-fogging agent may contain a sorbitan compound having one or more hydroxyl groups (hereinafter also referred to as "sorbitan compound D"). The number of hydroxyl groups in sorbitan compound D may be two or more, three or more, four or less, or three or less.

[0055] Sorbitan compound D may have polyoxyethylene groups. If sorbitan compound D has polyoxyethylene groups, the number of polyoxyethylene structural units (oxyethylene groups) may be 3 or more, 5 or more, or 6 or more, and may be 30 or less, 25 or less, or 20 or less.

[0056] Sorbitan compound D may also be a sorbitan fatty acid ester compound, which is an ester of sorbitan and a fatty acid. Examples of fatty acids include caprylic acid, capric acid, lauric acid, myristic acid, pentadecyl acid, palmitic acid, margaric acid, stearic acid, oleic acid, vaccenic acid, and linoleic acid.

[0057] If sorbitan compound D is a sorbitan fatty acid ester compound, the number of ester groups in sorbitan compound D may be one or more, three or less, or two or less.

[0058] Sorbitan compound D may be a sorbitan fatty acid ester compound having a polyoxyethylene group. Examples of sorbitan fatty acid ester compounds having a polyoxyethylene group include polyoxyethylene sorbitan monolaurate (such as TW-L120 and TW-L106 manufactured by Kao Corporation) and polyoxyethylene sorbitan monooleate (such as TW-O120 and TW-O106 manufactured by Kao Corporation).

[0059] The structure of compound E is determined according to the structure of the silane coupling agent C and the structure of the sorbitan compound D. Compound E may contain, for example, a compound represented by any of the general formulas (4) to (6). Compound E may contain a condensate of a compound represented by any of the general formulas (4) to (6), or a condensate of a compound represented by any of the general formulas (4) to (6) and the silane coupling agent C.

[0060] [In formula (4), R ４１ , R ４２ , and R ４3 Each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, R ４４ , and R ４５ Each of these independently represents a hydrogen atom or a monovalent organic group, and e represents an integer from 1 to 10.

[0061] [In formula (5), R ５１ , R ５２ , and R ５３ Each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, R ５４ [where f represents a hydrogen atom or a monovalent organic group, and f represents an integer from 1 to 10.]

[0062] [In formula (6), R ６１ , R ６２ , and R ６３ Each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, R ６４ [where g represents a hydrogen atom or a monovalent organic group, g represents an integer from 1 to 10, and h represents an integer from 1 to 10.]

[0063] In formula (4), R４１ , R ４２ , and R ４３ Each of these may independently be a hydrogen atom, a methyl group, or an ethyl group. ４４ and R ４５ Each of these may independently be a hydrogen atom or a structure derived from sorbitan compound D. e may be an integer from 1 to 8, 1 to 5, or 1 to 3.

[0064] In formula (5), R ５１ , R ５２ , and R ５３ Each of these may independently be a hydrogen atom, a methyl group, or an ethyl group. ５４ f may be a hydrogen atom or a structure derived from sorbitan compound D. f may be an integer from 1 to 8, 1 to 5, or 1 to 3.

[0065] In formula (6), R ６１ , R ６２ , and R ６３ Each of these may independently be a hydrogen atom, a methyl group, or an ethyl group. ６４ g may be a hydrogen atom or a structure derived from sorbitan compound D. g may be an integer from 1 to 8, 1 to 5, or 1 to 3. h may be an integer from 1 to 8, 1 to 5, or 1 to 3.

[0066] Synthetic product E can be prepared, for example, by stirring a silane coupling agent C and a sorbitan compound D in an environment of 40 to 100°C for 0.5 to 24 hours. The mixing ratio of the silane coupling agent C and the sorbitan compound D may be 10 to 200 parts by mass or 30 to 100 parts by mass of the silane coupling agent C per 100 parts by mass of the sorbitan compound D.

[0067] The conditions for synthesizing compound E can be adjusted, for example, by changing the peak position that can be observed in the IR chart. Specifically, if the silane coupling agent C has an acid anhydride group, the peak of the acid anhydride group, 1780 cm⁻¹, can be observed in the IR chart before synthesis. －１ Nearby peaks, and 1850 cm －１The progression of the synthesis reaction can be confirmed by the fact that the peak in the vicinity becomes smaller in the IR chart after synthesis. Furthermore, if the silane coupling agent C has an epoxy group, the peak of the epoxy group at 910 cm² will appear in the IR chart before synthesis. －１ The decrease in the peak in the IR chart after synthesis confirms the progress of the synthesis reaction.

[0068] From the viewpoint of providing superior water resistance and moisture resistance of the anti-fogging film, the content of compound E may be 1 part by mass or more, 3 parts by mass or more, 5 parts by mass or more, 8 parts by mass or more, 10 parts by mass or more, 12 parts by mass or more, 15 parts by mass or more, 20 parts by mass or more, or 25 parts by mass or more per 100 parts by mass of inorganic particles, or it may be 100 parts by mass or less, 80 parts by mass or less, 60 parts by mass or less, 50 parts by mass or less, 40 parts by mass or less, 30 parts by mass or less, 20 parts by mass or less, or 15 parts by mass or less. From these viewpoints, the content of compound E may be 1 to 100 parts by mass, 1 to 60 parts by mass, 1 to 40 parts by mass, 1 to 20 parts by mass, 5 to 20 parts by mass, or 10 to 20 parts by mass per 100 parts by mass of inorganic particles.

[0069] From the viewpoint of providing superior water resistance and moisture resistance of the anti-fogging film, the content of synthetic compound E may be 10 parts by mass or more, 30 parts by mass or more, 50 parts by mass or more, or 100 parts by mass or more, or 500 parts by mass or less, 300 parts by mass or less, 200 parts by mass or less, or 150 parts by mass or less, per 100 parts by mass of the silane coupling agent F described later. From these viewpoints, the content of synthetic compound E may be 10 to 500 parts by mass, 30 to 300 parts by mass, 50 to 200 parts by mass, or 100 to 150 parts by mass, per 100 parts by mass of the silane coupling agent F.

[0070] From the viewpoint of providing superior water resistance and moisture resistance of the anti-fogging film, the content of compound E may be 1% by mass or more, 2% by mass or more, 3% by mass or more, or 4% by mass or more, based on the total amount of solids in the anti-fogging agent, and may also be 40% by mass or less, 30% by mass or less, 28% by mass or less, or 26% by mass or less. From these viewpoints, the content of compound E may be 1 to 40% by mass, 2 to 30% by mass, 3 to 28% by mass, or 4 to 26% by mass, based on the total amount of solids in the anti-fogging agent.

[0071] The anti-fogging agent of this embodiment may further contain a compound G obtained by reacting a silane coupling agent A with compound B, from the viewpoint of forming an anti-fogging film that is less prone to appearance defects after steam testing.

[0072] The content of synthetic compound G may be 1 part by mass or more, 3 parts by mass or more, 5 parts by mass or more, 12 parts by mass or more, 15 parts by mass or more, 20 parts by mass or more, or 25 parts by mass or more per 100 parts by mass of inorganic particles, from the viewpoint of forming an anti-fogging film that is less likely to cause appearance defects after steam testing. It may also be 100 parts by mass or less, 80 parts by mass or less, 60 parts by mass or less, 50 parts by mass or less, or 40 parts by mass or less.

[0073] The content of compound G may be 1% by mass or more, 2% by mass or more, 3% by mass or more, or 4% by mass or more, based on the total amount of solids of the antifogging agent, or it may be 40% by mass or less, 30% by mass or less, 28% by mass or less, or 26% by mass or less, from the viewpoint of forming an antifogging film that is less likely to produce appearance defects after steam testing.

[0074] (Silane coupling agent F having a polyether group) The antifogging agent of this embodiment may further contain a silane coupling agent F having a polyether group (hereinafter, this silane coupling agent will also be referred to as "silane coupling agent F") from the viewpoint of compatibility.

[0075] The silane coupling agent F may be a compound represented by the following general formula (7).

[0076] [In formula (7), R ７１ , R ７２ , R ７３ and R ７４ Each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, L ７１ and L ７２ Each of these independently represents an alkylene group having 1 to 6 carbon atoms, and k represents an integer from 3 to 25.

[0077] R ７１ , R ７２ , R ７３ and R ７４This may be a methyl group, an ethyl group, a propyl group, or a butyl group. ７１ and L ７２ k may be an ethylene group, a propylene group, or a butylene group. k may be 10 to 20 or 11 to 15.

[0078] Examples of silane coupling agents represented by general formula (7) include A1230 (manufactured by Momentive Performance Materials LLC) and X-12-641 (manufactured by Shin-Etsu Chemical Co., Ltd.).

[0079] From the viewpoint of compatibility, the content of the silane coupling agent F may be 1 part by mass or more, 3 parts by mass or more, 5 parts by mass or more, 8 parts by mass or more, or 10 parts by mass or more per 100 parts by mass of inorganic particles, and may also be 50 parts by mass or less, 40 parts by mass or less, 30 parts by mass or less, 20 parts by mass or less, 15 parts by mass or less, or 10 parts by mass or less. From these viewpoints, the content of the silane coupling agent F may be 1 to 50 parts by mass, 1 to 30 parts by mass, 1 to 15 parts by mass, 1 to 10 parts by mass, 3 to 10 parts by mass, 5 to 10 parts by mass, or 8 to 10 parts by mass per 100 parts by mass of inorganic particles.

[0080] The content of the silane coupling agent F may be 10 parts by mass or more, 30 parts by mass or more, 50 parts by mass or more, or 80 parts by mass or more per 100 parts by mass of the synthetic product E, or it may be 500 parts by mass or less, 400 parts by mass or less, 300 parts by mass or less, or 200 parts by mass or less, from the viewpoint of compatibility.

[0081] The content of the silane coupling agent F may be 1% by mass or more, 3% by mass or more, 5% by mass or more, or 7% by mass or more, based on the total amount of solids in the antifogging agent, and may also be 30% by mass or less, 20% by mass or less, 15% by mass or less, or 13% by mass or less. From these viewpoints, the content of the silane coupling agent F may be 1 to 30% by mass, 3 to 20% by mass, 5 to 15% by mass, or 7 to 13% by mass, based on the total amount of solids in the antifogging agent.

[0082] (Other silane coupling agents) The anti-fogging agent of this embodiment may contain silane coupling agents other than silane coupling agent A and silane coupling agent F described above. Examples include silane coupling agents having branched or linear alkyl groups of C1 to C30, cycloalkyl groups of C3 to C10, aryl groups of C6 to C10, or fluoro groups.

[0083] Silane coupling agents having branched or linear alkyl groups of C1 to C30 include methyltrimethoxysilane (KBM-13, manufactured by Shin-Etsu Chemical Co., Ltd.), ethyltrimethoxysilane, propyltrimethoxysilane (KBM-3033, manufactured by Shin-Etsu Chemical Co., Ltd.), butyltrimethoxysilane, pentyltrimethoxysilane, hexyltrimethoxysilane (KBM-3063, manufactured by Shin-Etsu Chemical Co., Ltd.), heptyltrimethoxysilane, octyltrimethoxysilane, nonyltrimethoxysilane, decyltrimethoxysilane (KBM-3103C, manufactured by Shin-Etsu Chemical Co., Ltd.), undecyltrimethoxysilane, dodecyltrimethoxysilane, and tetradecyltrimethoxysilane. Examples include stearyltrimethoxysilane, methyltriethoxysilane (such as KBE-13 manufactured by Shin-Etsu Chemical Co., Ltd.), ethyltriethoxysilane, propyltriethoxysilane (such as KBE-3033 manufactured by Shin-Etsu Chemical Co., Ltd.), butyltriethoxysilane, pentyltriethoxysilane, hexyltriethoxysilane (such as KBE-3063 manufactured by Shin-Etsu Chemical Co., Ltd.), heptyltriethoxysilane, octyltriethoxysilane (such as KBE-3083 manufactured by Shin-Etsu Chemical Co., Ltd.), nonyltriethoxysilane, decyltriethoxysilane, undecyltriethoxysilane, dodecyltriethoxysilane, tetradecyltriethoxysilane, and stearyltriethoxysilane.

[0084] Examples of silane coupling agents having C6 to C10 aryl groups include phenyltrimethoxysilane (KBM-103, KBM-202SS, KBE-103, KBE-202, etc., manufactured by Shin-Etsu Chemical Co., Ltd.) and p-styryltrimethoxysilane (KBM-1403, etc., manufactured by Shin-Etsu Chemical Co., Ltd.).

[0085] Examples of silane coupling agents containing a fluoro group include 3,3,3-trifluoropropyltrimethoxysilane (such as KBM-7103 manufactured by Shin-Etsu Chemical Co., Ltd.).

[0086] (Binder Compound) The antifogging agent of this embodiment may further contain a binder compound. A binder compound is a compound that improves the strength of the antifogging film by bonding with inorganic particles and crosslinking them. Examples of binder compounds include epoxy compounds, polyvinyl alcohol, modified polyvinyl alcohol, polyacrylic acid, acrylic resin, epoxy resin, urethane resin, polyvinylpyrrolidone, polyvinylpyrrolidone vinyl acetate copolymer (vinylpyrrolidone acetate copolymer), polyamine resin, cellulose, dextrin, cellulose nanofiber, silicate oligomer, silicate polymer, etc. Binder compounds can be used individually or in combination of two or more.

[0087] The binder compound may be an epoxy compound, from the viewpoint of providing excellent fogging resistance for the anti-fogging film. Examples of epoxy compounds include polyfunctional epoxy compounds such as ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, and polypropylene glycol diglycidyl ether.

[0088] Examples of silane oligomers include ethyl silicate 40, ethyl silicate 48, EMS-485, methyl silicate 51, methyl silicate 53A, Colcoat PX, and Colcoat N-103X (all manufactured by Colcoat Co., Ltd.).

[0089] The content of the binder compound may be 0.1 parts by mass or more, 0.5 parts by mass or more, 1 part by mass or more, 3 parts by mass or more, or 5 parts by mass or more per 100 parts by mass of inorganic particles, or 1000 parts by mass or less, 500 parts by mass or less, 100 parts by mass or less, 50 parts by mass or less, 30 parts by mass or less, or 10 parts by mass or less, from the viewpoint of having better water resistance and moisture resistance of the anti-fogging film. The content of the binder compound may be 0.1 to 1000 parts by mass, 0.5 to 500 parts by mass, 1 to 100 parts by mass, 3 to 50 parts by mass, or 5 to 10 parts by mass per 100 parts by mass of inorganic particles.

[0090] The binder compound content may be 0.1 to 30% by mass, 0.3 to 20% by mass, or 0.5 to 10% by mass, based on the total amount of solids in the anti-fogging agent, from the viewpoint of providing superior water resistance and moisture resistance of the anti-fogging film.

[0091] (Metal Catalyst) The antifogging agent of this embodiment may further contain a metal catalyst. The metal catalyst functions as a bonding-promoting material, and the inclusion of a metal catalyst in the antifogging agent makes it easier to form an antifogging film with excellent moisture resistance and water resistance.

[0092] The metal catalyst is not particularly limited and can be selected from known metal catalysts. Examples of metal catalysts include zirconium compounds, titanium compounds, nickel compounds, aluminum compounds, tin compounds, and the like.

[0093] The metal catalyst may be a zirconium compound, an aluminum compound, or a nickel compound, from the viewpoint of providing superior moisture resistance and water resistance of the anti-fogging film. By including at least one selected from the group consisting of zirconium compounds and aluminum compounds as the metal catalyst in the anti-fogging agent, the number of bonding sites with inorganic particles (e.g., silica particles) increases, making it easier to form stronger bonds.

[0094] The metal catalyst may be a commercially available product.

[0095] The anti-fogging agent according to this embodiment may contain additives such as antioxidants, ultraviolet absorbers, and light stabilizers. In addition to acetic acid, the anti-fogging agent may also contain nitric acid, hydrochloric acid, phosphoric acid, p-toluenesulfonic acid, benzenesulfonic acid, methanesulfonic acid, phenolsulfonic acid, oxalic acid, maleic acid, malonic acid, tartaric acid, citric acid, malic acid, acetic acid, lactic acid, succinic acid, benzoic acid, ammonia, urea, imidazole, sodium carbonate, calcium carbonate, sodium acetate, etc., as defoaming agents, catalysts, etc., used when preparing the raw materials. From the viewpoint of adjusting the viscosity of the anti-fogging agent, the anti-fogging agent may contain a thickening agent.

[0096] The anti-fogging agent may be non-surfactant. Non-surfactant means that the amount of surfactants known to be components of anti-fogging agents is 1% by mass or less, based on the total amount of solids in the anti-fogging agent. The anti-fogging agent may not contain surfactants at all (the amount of surfactants may be substantially 0% by mass, based on the total amount of solids in the anti-fogging agent). Examples of surfactants include anionic surfactants, cationic surfactants, nonionic surfactants, and amphoteric surfactants.

[0097] (Liquid medium) The anti-fogging agent may contain a liquid medium. The liquid medium may be a medium that disperses inorganic particles, dissolves silane coupling agent A, compound B, compound E, silane coupling agent F, etc. in the anti-fogging agent. The boiling point of the liquid medium may be 185°C or lower, from the viewpoint that the liquid medium will volatilize when heated during the formation of the anti-fogging film, bringing the inorganic particles closer together and facilitating the formation of bonds between the inorganic particles. The liquid medium may be the same as the dispersion medium contained in the silica particle dispersion, or it may be a different one.

[0098] As a liquid medium, for example, water, organic solvents, or mixed solvents thereof can be used. Examples of organic solvents include alcohols such as methyl alcohol, ethyl alcohol, 1-propanol, isopropyl alcohol, 1-butyl alcohol, 2-butyl alcohol, isobutyl alcohol, diacetone alcohol, 1-butoxy-2-propanol, 1-hexanol, 1-octanol, 2-octanol, and 3-methoxy-3-methyl-1-butanol; glycols such as polyethylene glycol; glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol mono-tert-butyl ether, propylene glycol monomethyl ether acetate, propylene glycol n-propyl ether, and propylene glycol monomethyl ether; ketones such as acetone and methyl ethyl ketone; ethers such as 1,2-dimethoxyethane, tetrahydrofuran, and dioxane; esters such as ethyl acetate and butyl acetate; cyclic hydrocarbons such as cyclohexane; and acetonitrile.

[0099] <Method for preventing fogging of vehicle lamp structures> The anti-fogging agent according to this embodiment can be used to prevent fogging of vehicle lamp structures. The method for preventing fogging of vehicle lamp structures may include, for example, a step of applying the anti-fogging agent to the inner surface of the lens of the vehicle lamp structure to form a coating film (coating step), and a step of drying the coating film (drying step). Prior to the coating step, a cleaning step may be further included for the purpose of removing any release agent adhering to the surface of the lens.

[0100] (Cleaning process) The cleaning solution used in the cleaning process is not particularly limited. If the surface substrate inside the lens of the vehicle lamp structure is polycarbonate, any liquid that does not dissolve the polycarbonate substrate is acceptable, such as water or alcohols. More specifically, it may be water, isopropyl alcohol, methanol, ethanol, etc. The cleaning process may include a step of wiping the substrate with a cloth soaked in the cleaning solution.

[0101] (Coating process) The coating process is, for example, a process of applying an anti-fogging agent to the inner surface of a lens provided in a vehicle lamp structure. The anti-fogging agent may be applied to the entire inner surface of the lens or selectively to a part of it.

[0102] The method of applying the anti-fogging agent is not particularly limited and may include, for example, spin coating, dip coating, spray coating, flow coating, bar coating, gravure coating, etc. The anti-fogging agent may also be applied by impregnating it with cloth or the like. The application method of the anti-fogging agent may be spray coating, from the viewpoint of easily forming a coating film of uniform thickness even on uneven surfaces, and from the viewpoint of high productivity and high utilization efficiency of the anti-fogging agent. These methods can be used individually or in combination of two or more.

[0103] The amount to be applied is not limited as it depends on the components and amount of the anti-fogging agent, but for example, 10 －９ ~10 ３ g / m ２ That's fine.

[0104] The temperature of the antifogging agent used in the coating process may be, for example, 1 to 50°C or 10 to 30°C. A temperature of 1°C or higher makes it easier to further improve antifogging properties and adhesion, while a temperature of 50°C or lower makes it easier to improve the transparency of the antifogging film. The treatment time with the antifogging agent may be, for example, 1 second to 1 hour or 5 to 30 minutes.

[0105] (Drying process) The drying process may involve applying the anti-fog agent and then allowing the liquid medium to volatilize from the anti-fog agent. The liquid medium can be allowed to volatilize by leaving it at room temperature (e.g., 20°C). The adhesion between the inner surface of the lens and the anti-fog film can be further improved by performing the drying process at a higher temperature. The temperature of the drying process can be adjusted according to the heat resistance temperature of the lens, for example, 5 to 300°C or 10 to 200°C. A temperature of 5°C or higher can further improve adhesion, while a temperature of 300°C or lower can further suppress deterioration due to heat. The drying time can be 30 seconds to 150 hours. Through this process, a silica-based anti-fog film is formed on the inner surface of the lens.

[0106] The thickness of the anti-fogging film is not particularly limited, but from the viewpoint of transparency, anti-fogging properties, etc., it may be 100 nm to 1000 μm, 500 nm to 10 μm, or 1000 nm to 5 μm. The film thickness of the anti-fogging film can be measured, for example, by the automatic film thickness measurement system F50 (manufactured by Filmetrics Co., Ltd.).

[0107] Figure 1 is a schematic diagram of a vehicle lamp structure. The inner surface of the lens of the vehicle lamp structure is treated with an anti-fogging agent according to this embodiment. That is, the vehicle lamp structure has an anti-fogging film formed from the anti-fogging agent on the inner surface of the lens. The lamp structure 10 shown in Figure 1 comprises a lamp housing 3 configured as a recessed shape with one end open, and a lens 1 that closes the open side of the lamp housing 3. The material of the lens 1 is, for example, polycarbonate. The lamp housing 3 and the lens 1 form a lamp chamber S. A light source 4 is mounted on the lamp housing 3 and is placed inside the lamp chamber S. An incandescent bulb, LED bulb, halogen bulb, etc., can be appropriately used as the light source 4. Inside the lamp chamber S, as shown in the figure, a reflector 5 that functions as a reflector for the light of the light source 4 may be provided so as to surround the light source 4 from the rear. An anti-fogging film 2 formed from the anti-fogging agent is provided on the inner surface of the lens 1, that is, the surface facing the lamp chamber S. The anti-fog film 2 may be provided on the entire inner surface of the lens 1, or it may be selectively provided on a part of it, as shown in Figure 1.

[0108] <Hydrophilic Agent> The anti-fogging agent of this embodiment can make the substrate surface hydrophilic, and therefore can be called a hydrophilic agent. The hydrophilic surface does not lose much hydrophilicity even after a fogging test, and can form a good water film when moisture adheres to it. As a result, it is possible to suppress the occurrence of fogging on the substrate even in environments where it is exposed to volatile components. The treatment of the substrate can be carried out in the same way as the anti-fogging method described above.

[0109] Examples of materials constituting the base material include resin materials such as polycarbonate, acrylic polymer, polyamide, polyacrylate, polyimide, acrylonitrile-styrene copolymer, styrene-acrylonitrile-butadiene copolymer, polyvinyl chloride, polyethylene, and polycarbonate; metallic materials such as aluminum, magnesium, copper, zinc, iron, titanium, chromium, manganese, cobalt, and nickel; inorganic materials such as silicon dioxide, aluminum oxide, magnesium oxide, copper oxide, zinc oxide, iron oxide, titanium oxide, chromium oxide, manganese oxide, cobalt oxide, and nickel oxide; and glass. Articles equipped with such a base material include the above-mentioned vehicle lamp structures (such as automobile headlights), as well as vehicle windshields, eyeglasses, goggles, mirrors, storage containers, windows, and camera lenses.

[0110] Next, the present disclosure will be further described by the following embodiments, but these embodiments are not intended to limit the present disclosure.

[0111] <Preparation of Silane-Modified Resin> 10 g of Rheodol TW-L120 (manufactured by Kao Corporation) and 6.4 g of a silane coupling agent containing an acid anhydride (manufactured by Shin-Etsu Chemical Co., Ltd., 3-trimethoxysilylpropyl succinic anhydride, trade name: X-12-967C) were mixed, stirred at 60°C for 2 hours, and diluted with 147.7 g of water to obtain a silane-modified resin.

[0112] <Preparation of Anti-fogging Agent> A total of 1.2 g (silica solid content; mixing ratio 75:25 in Examples 1-9 and Comparative Examples 1-3, and 0:100 in Example 10) of Snowtex O (spherical silica particles, manufactured by Nissan Chemical Corporation, concentration 20% by mass) and Snowtex OUP (bead-shaped silica particles, manufactured by Nissan Chemical Corporation, concentration 15% by mass) was mixed, along with 0.6 g of acetic acid, 0.1 g of a silane coupling agent having a polyether group (manufactured by Momentive, trade name: A1230), and a silane coupling agent having an epoxy group (manufactured by Shin-Etsu Chemical Co., Ltd., 3-glycyrrhea X g of diloxypropyltrimethoxysilane (trade name: KBM403) (the amount of which the blending amount (parts by mass) per 100 parts by mass of inorganic particles is the value shown in Tables 1 and 2), 0.1 g of silane-modified resin (solid content), Y g of a 30% by mass aqueous solution of an amino group-containing polyether compound (manufactured by HUNTSUMAN, trade name: ED-2003) (the amount of which the blending amount (parts by mass, solid content) per 100 parts by mass of inorganic particles is the value shown in Tables 1 and 2), 2.5 g of water, and 9.0 g of IPA were mixed and stirred for 2 hours to obtain the mother liquor.

[0113] A diluted solution was prepared by mixing 2.4 g of water, 13.8 g of IPA, and 3.8 g of ethylene glycol monobutyl ether. This diluted solution was mixed with the mother liquor to obtain an anti-fogging agent.

[0114] (Examples 1-10, Comparative Examples 1-3) Mother liquor and diluent were prepared so that the blending amounts (parts by mass) of KBM403 and ED2003 per 100 parts by mass of inorganic particles were the values ​​shown in Tables 1 and 2, and an antifogging agent was obtained by mixing the mother liquor and diluent in a 1:1 mass ratio.

[0115] <Formation of anti-fogging film on polycarbonate substrate> A 10 cm square x 2 mm thick polycarbonate substrate was cleaned with isopropyl alcohol. The anti-fogging agent obtained in the example was applied to the substrate using an applicator or spray, and heated at 110°C for 30 minutes to obtain a polycarbonate substrate as a test material.

[0116] <Evaluation> (Steam Test) Hot water at 60°C was prepared, and the hot water and the anti-fog film of the test material were placed facing each other so that the distance between the surface of the hot water and the surface of the anti-fog film was 1 cm. Steam was then irradiated onto the anti-fog film. After irradiating with steam for 3 minutes, the anti-fog film was dried, and the presence or absence of defects in the appearance of the anti-fog film was observed visually. If no defects occurred, it was classified as "A", and if defects occurred, it was classified as "B".

[0117]

[0118]

[0119] 1...Lens, 2...Anti-fog film, 3...Lamp housing, 4...Light source, 5...Reflector, S...Lamp chamber, 10...Lamp structure.

Claims

1. An anti-fogging agent comprising inorganic particles, a silane coupling agent A having a reactive group X, and a compound B having a reactive group Y capable of reacting with and bonding to the reactive group X, wherein the content of the silane coupling agent A is 5 parts by mass or more per 100 parts by mass of the inorganic particles, and the content of the compound B is 0.2 parts by mass or more per 100 parts by mass of the inorganic particles.

2. The anti-fogging agent according to claim 1, wherein the inorganic particles are silica.

3. The anti-fogging agent according to claim 1, wherein the content of the silane coupling agent A is 70 parts by mass or less per 100 parts by mass of the inorganic particles.

4. The anti-fogging agent according to claim 1, wherein the content of compound B is 270 parts by mass or less per 100 parts by mass of the inorganic particles.

5. The anti-fogging agent according to claim 1, wherein the content of the silane coupling agent A is 50 parts by mass or more per 100 parts by mass of the compound B.

6. The anti-fogging agent according to claim 1, wherein one of the reactive group X and the reactive group Y is an epoxy group, a carboxyl group, a hydroxyl group, or an acid anhydride group, and the other is an amino group, an isocyanate group, or a ureido group.

7. The anti-fogging agent according to claim 1, wherein the reactive group X is an epoxy group and the reactive group Y is an amino group.

8. The antifogging agent according to claim 1, wherein compound B has a polyether group.

9. The antifogging agent according to claim 1, further comprising a silane coupling agent having a polyether group.

10. A method for preventing fogging of a vehicle lamp structure, comprising the steps of: applying an anti-fogging agent according to any one of claims 1 to 9 to the inner surface of a lens provided in the vehicle lamp structure to form a coating film; and drying the coating film.

11. A vehicle lamp structure comprising an anti-fog film formed on the inner surface of the lens from an anti-fog agent according to any one of claims 1 to 9.

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