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

Abstract

This anti-fogging agent contains: silica particles; a silane coupling agent X having a reactive group X; and a polyether compound Y having at least two reactive groups Y capable of reacting with the reactive group X and bonding thereto.

Description

Antifogging agent, antifogging method for vehicle lamp structure, and vehicle lamp structure

[0001] The present disclosure relates to an antifogging agent, an antifogging method for a vehicle lamp structure, and a vehicle lamp structure.

[0002] A method is known in which an antifogging agent composition containing a surfactant is applied to the interior of a lamp chamber of a vehicle lamp structure for an automobile or the like, which is susceptible to fogging due to condensation (see, for example, Patent Document 1). When moisture adheres to an antifogging film formed by an antifogging agent containing a surfactant, the moisture instantly turns into a water film due to the effect of the surfactant, thereby suppressing the occurrence of fogging.

[0003] JP 2016-027134 A

[0004] However, it has been found that the anti-fogging properties of the above-mentioned anti-fogging film may be reduced when water droplets adhering to the surface of the anti-fogging film or moisture in the air cause the surfactant in the anti-fogging film to migrate to the moisture side.

[0005] One aspect of the present disclosure has been made in view of the above circumstances, and aims to provide a novel antifogging agent capable of forming a silica-based antifogging film that is excellent in water resistance and moisture resistance, a method for preventing fogging of a vehicle lamp structure using the antifogging agent, and a vehicle lamp structure using the antifogging agent.

[0006] One aspect of the present invention includes the following [1] to [7]. [1] An antifogging agent containing silica particles, a silane coupling agent X having a reactive group X, and a polyether compound Y having two or more reactive groups Y capable of reacting with the reactive group X to form a bond. [2] The antifogging agent according to [1], wherein one of the reactive group X and the reactive group Y is an epoxy group, a carboxyl group, a hydroxy group, or an acid anhydride group, and the other is an amino group, an isocyanate group, or a ureido group (provided that the two or more reactive groups Y may be the same or different). [3] The antifogging agent according to [1] or [2], wherein the reactive group X is an epoxy group and the reactive group is an amino group. [4] The antifogging agent according to any one of [1] to [3], further containing a compound A obtained by reacting a silane coupling agent A having an acid anhydride group or an epoxy group with a sorbitan compound having a hydroxy group. [5] The antifogging agent according to any one of [1] to [4], further containing a silane coupling agent B having a polyether group. [6] 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 [5] to an inner surface of a lens provided in the vehicle lamp structure to form a coating film, and drying the coating film. [7] A vehicle lamp structure, comprising an antifogging film formed from the antifogging agent according to any one of [1] to [5] on the inner surface of the lens.

[0007] According to one aspect of the present disclosure, it is possible to provide a novel antifogging agent capable of forming an antifogging film having excellent water resistance and moisture resistance, a method for preventing fogging of a vehicle lamp structure using the antifogging agent, and a vehicle lamp structure using the antifogging agent.

[0008] Fig. 1 is a diagram schematically showing a vehicle lamp structure. Fig. 2 is a diagram showing IR charts before and after synthesis of Compound 1. Fig. 3 is a diagram showing IR charts before and after synthesis of Compound 1. Fig. 4 is a diagram for explaining a method for evaluating an antifogging agent.

[0009] Preferred embodiments of the present invention will be described in detail below, with reference to the drawings where appropriate. However, the present invention is not limited to the following embodiments. The materials exemplified below may be used singly or in combination, unless otherwise specified. When multiple substances corresponding to each component are present in the composition, the content of each component refers to the total amount of the multiple substances present in the composition, unless otherwise specified. Numerical ranges indicated using "to" indicate ranges that include the numerical values ​​before and after "to" as the minimum and maximum values, respectively. In the numerical ranges described in stages in this specification, the upper or lower limit of a certain numerical range may be replaced with the upper or lower limit of a numerical range of another stage. In the numerical ranges described in this specification, the upper or lower limit of the numerical range may be replaced with the values ​​shown in the examples.

[0010] <Anti-Fog Agent> The anti-fogging agent of this embodiment contains silica particles, a silane coupling agent X having a reactive group X (hereinafter, this silane coupling agent will also be referred to as "silane coupling agent X"), and a polyether compound Y having two or more reactive groups Y capable of reacting with and bonding to the reactive group X (hereinafter, this polyether compound will also be referred to as "polyether compound Y"). The anti-fogging agent of this embodiment can form a silica-based anti-fogging film having sufficient water resistance and moisture resistance.

[0011] The inventors speculate that the reason for this effect is as follows: With the anti-fogging agent having the above-described configuration, the silica is bonded by the reaction product of the silane coupling agent X and the polyether compound Y, and the polyether structure is incorporated between the silica particles, which is thought to enable the formation of a strong film with improved flexibility.

[0012] (Silica Particles) The shape of the silica particles is not particularly limited. Examples of the shape of the silica particles include a beaded shape (pearl necklace shape), a chain shape, a spherical shape, a cocoon shape, an association shape, and a confetti shape. The silica particles may be colloidal silica. Two or more different shapes may be mixed.

[0013] The silica particles may contain a metal oxide 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 the colloidal silica to stabilize the silica sol.

[0014] The average particle size of the silica particles may be 1 to 1000 nm. When the average particle size is 1 nm or more, the silica particles are less likely to aggregate in the antifogging agent, and therefore the silica particles are more likely to adhere to the substrate. On the other hand, when the average particle size is 1000 nm or less, the specific surface area of ​​the silica particles is increased, and therefore the silica particles are more likely to adhere to the substrate. From these viewpoints, the average particle size of the silica particles may be 3 to 500 nm or 5 to 200 nm.

[0015] In this specification, the average particle size of silica particles can be measured, for example, by the following procedure. A diluted solution is obtained by diluting with ion-exchanged water or any solvent so that the silica particle content is approximately 1.0 mass % (a content at which the transmittance (H) during measurement is 60 to 70%). The diluted solution can then be subjected to dynamic light scattering (manufactured by Otsuka Electronics Co., Ltd., product name: nanoSAQLA) to measure the average particle size of the silica particles.

[0016] 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, and ethyl acetate. The dispersion medium may be a mixture of the above dispersion media. From the viewpoint of versatility, the dispersion medium for silica particles may be water.

[0017] The raw material for silica particles may be water glass or alkoxysilane. When the raw material is water glass, the silica particle production process may involve, for example, heating and concentrating sodium silicate using a hydrothermal synthesis method to produce silica particles. Specifically, the silica particles may be produced by producing aggregates with a three-dimensional network structure at an acidic pH to suppress the growth of primary particles and then disintegrating them, or by accelerating the growth of primary particles at an alkaline pH to produce block-shaped aggregates and then disintegrating them. When the raw material is alkoxysilane, the silica particle production process may involve, for example, sol-gel synthesis of the alkoxysilane to produce silica particles. Specifically, the silica particles may be produced by promoting the hydrolysis reaction of the alkoxysilane, then promoting a polycondensation reaction to obtain a gel, and then removing the solvent by heat treatment, or by solvent substitution with a predetermined solvent after obtaining the gel.

[0018] As the dispersion liquid of silica particles, commercially available products can be used. For example, ST-PS-SO, ST-PS-MO, ST-PS-M, ST-PS-S, ST-UP, ST-OUP, IPA-ST-UP, MA-ST-UP, PGM-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-40, ST-CM, ST-30L, ST-OL, ST-AK-L, ST-YL, ST-OYL, ST-AK-YL, ST-ZL, MP-1040, MP-2040, MP-4540M manufactured by Nissan Chemical Industries, Ltd.; PL-1-IPA, PL-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 manufactured by Fuso Chemical Co., Ltd.; TCSOL800 manufactured by Tama Chemical Industry Co., Ltd.; SI-40, SI-50, SI-45P, SI-80P, SIK-23, S-30H, SIK-15, SI-550, etc. manufactured by JGC Catalysts and Chemicals Ltd.

[0019] The content of silica particles 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 antifogging agent, from the viewpoint of excellent antifogging properties. The content of silica particles 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 antifogging agent, from the viewpoint of easily maintaining antifogging properties (hydrophilicity). From these viewpoints, the content of silica particles 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 antifogging agent.

[0020] (Silane coupling agent X) The reactive group X of the silane coupling agent X may be an epoxy group, a carboxyl group, a hydroxyl group, or an acid anhydride group, or may be an amino group, an isocyanate group, or an ureido group.When the reactive group Y is an amino group, an isocyanate group, or an ureido group, the reactive group X may be an epoxy group, a carboxyl group, a hydroxyl group, or an acid anhydride group;When 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 an ureido group.

[0021] Examples of silane coupling agents having an epoxy group include 3-glycidyloxypropyltrimethoxysilane (KBM-403 manufactured by Shin-Etsu Chemical Co., Ltd., etc.), 8-glycidoxyoctyltrimethoxysilane (KBM-4803 manufactured by Shin-Etsu Chemical Co., Ltd., etc.), 3-glycidyloxypropyltriethoxysilane (KBE-403 manufactured by Shin-Etsu Chemical Co., Ltd., etc.), KBE-402, X-12-981S, and X-12-984S (all trade names, manufactured by Shin-Etsu Chemical Co., Ltd.), and the like.

[0022] An example of a silane coupling agent having a carboxyl group is X-12-1135 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.).

[0023] Examples of silane coupling agents having an amino group include 3-aminopropyltrimethoxysilane (e.g., KBM-903 manufactured by Shin-Etsu Chemical Co., Ltd.), 3-aminopropyltriethoxysilane (e.g., KBE-903 manufactured by Shin-Etsu Chemical Co., Ltd.), N-2-(aminoethyl)-3-aminopropyltrimethoxysilane (e.g., KBM-603 manufactured by Shin-Etsu Chemical Co., Ltd.), N-2-(aminoethyl)-8-aminooctyltrimethoxysilane (e.g., KBM-6803 manufactured by Shin-Etsu Chemical Co., Ltd.), N-2-(aminoethyl)-3-aminopropyltriethoxysilane (e.g., KBE-603 manufactured by Shin-Etsu Chemical Co., Ltd.), and N-phenyl-3-aminopropyltrimethoxysilane. (e.g., KBM-573 manufactured by Shin-Etsu Chemical Co., Ltd.), N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane (e.g., KBM-602 manufactured by Shin-Etsu Chemical Co., Ltd.), N-2-(aminoethyl)-3-aminopropylmethyldiethoxysilane (e.g., KBE-602 manufactured by Shin-Etsu Chemical Co., Ltd.), N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane (e.g., KBM-575 manufactured by Shin-Etsu Chemical Co., Ltd.), 3-triethoxysilyl-N-(1,3-dimethyl-butylidene)propylamine (e.g., KBE-9103P manufactured by Shin-Etsu Chemical Co., Ltd.), and X-12-972F (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.).

[0024] The silane coupling agent X may be a silane coupling agent represented by general formula (X).

[0025] [In formula (X), R １ , R ２ , and R 3 each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, s represents an integer of 1 to 10, and t represents an integer of 1 to 10.

[0026] In formula (X), R １ , R ２ , and R ３ may each independently be a hydrogen atom, a methyl group, or an ethyl group. s may be an integer of 1 to 8, 1 to 5, or 1 to 3. t may be an integer of 1 to 8, 1 to 5, or 1 to 3.

[0027] The content of the silane coupling agent X can be appropriately set depending on the content of the polyether compound Y, and may be 0.1 parts by mass or more, or 1 part by mass or more, and may be 100 parts by mass or less, or 50 parts by mass or less, relative to 100 parts by mass of the silica particles. The content of the silane coupling agent X may be 0.1 to 100 parts by mass, or 1 to 50 parts by mass, relative to 100 parts by mass of the silica particles.

[0028] The content of silane coupling agent X can be appropriately set depending on the content of polyether compound Y, and may be 0.1 mass % or more, or 1 mass % or more, or 50 mass % or less, based on the total amount of solids in the antifogging agent. The content of silane coupling agent X may be 0.1 to 50 mass % based on the total amount of solids in the antifogging agent.

[0029] (Polyether compound Y) The reactive group Y of the polyether compound Y may be an epoxy group, a carboxyl group, a hydroxyl group, or an acid anhydride group, or may be an amino group, an isocyanate group, or an ureido group; when the reactive group X is an epoxy group, a carboxyl group, a hydroxyl group, or an acid anhydride group, it may be an amino group, an isocyanate group, or an ureido group; when the reactive group X is an amino group, an isocyanate group, or an ureido group, it may be an epoxy group, a carboxyl group, a hydroxyl group, or an acid anhydride group. Note that two or more reactive groups Y may be the same or different.

[0030] The polyether compound Y may have a polyether chain as a main chain. The polyether chain is represented by the formula -(R-O) ｎ - (wherein R is C ２ H ４ or C ３ H ６ where n is an integer. The polyether chain may contain one or both of a repeating unit derived from ethylene oxide and a repeating unit derived from propylene oxide, and when both are contained, the polyether chain may be random or block.

[0031] The polyether compound Y may be a polyetherdiamine compound represented by the general formula (Y) from the viewpoint of being a hydrophilic compound having a reactive site.

[0032] [In formula (Y), x, y, and z each represent an integer of 1 to 100.]

[0033] In formula (Y), x + z may be 6.0 or less and y may be 39 or less, or x + z may be 3.6 or less and y may be 9.0 or less, or x + z may be 6.0 or less and y may be 12.5 or less.

[0034] 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 polyether diamine compound satisfying these conditions is blended, an anti-fogging film with excellent water film uniformity can be formed, and in a vehicle lamp structure, the straightness and intensity of transmitted light can be sufficiently maintained while suppressing the occurrence of fogging.

[0035] From the same viewpoint as above, y / (x+z) in formula (Y) may be 3 to 8.

[0036] As the polyether compound Y, commercially available products such as "ED-600", "ED-900", and "ED-2003" (trade names, manufactured by HUNTSUMANS CO., LTD.) may be used.

[0037] From the viewpoint of compatibility, the content of polyether compound Y may be 0.01 parts by mass or more, or 0.1 parts by mass or more, and may be 10 parts by mass or less, or 1.0 part by mass or less, relative to 100 parts by mass of silica particles. The content of polyether compound Y may be 0.01 to 10 parts by mass, or 0.1 to 1.0 part by mass, relative to 100 parts by mass of silica particles.

[0038] From the viewpoint of compatibility, the content of polyether compound Y may be 0.01% by mass or more, or 0.1% by mass or more, and may be 5.0% by mass or less, based on the total amount of solids in the antifogging agent. The content of polyether compound Y may be 0.01 to 5.0% by mass, based on the total amount of solids in the antifogging agent.

[0039] (Synthetic Product A) From the viewpoint of water resistance and moisture resistance, the antifogging agent of the present embodiment may further contain a synthetic product A obtained by reacting a silane coupling agent A having an acid anhydride group or an epoxy group (hereinafter, this silane coupling agent will also be referred to as "silane coupling agent A") with a sorbitan compound having a hydroxy group (hereinafter, this sorbitan compound will also be referred to as "sorbitan compound A").

[0040] [Silane Coupling Agent A] The silane coupling agent having an acid anhydride group may be, for example, a silane coupling agent represented by general formula (1).

[0041] [In formula (1), R 1１ , R 1２ , and R 13 each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and a represents an integer of 1 to 10.

[0042] In formula (1), R 1１ , R 1２ , and R 13 may each independently be a hydrogen atom, a methyl group, an ethyl group, a propyl group, or a butyl group, and a may be an integer of 1 to 8, 1 to 5, or 1 to 3.

[0043] 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.).

[0044] 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).

[0045] [In formula (2), R ２１ , R ２２ , and R ２3 each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and b represents an integer of 1 to 10.

[0046] [In formula (3), R ３１ , R ３２ , and R ３3each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, c represents an integer of 1 to 10, and d represents an integer of 1 to 10.

[0047] In formula (2), R 2１ , R 2２ , and R 2３ may each independently be a hydrogen atom, a methyl group, or an ethyl group, and b may be an integer of 1 to 8, 1 to 5, or 1 to 3.

[0048] In formula (3), R ３１ , R ３２ , and R ３３ may each independently be a hydrogen atom, a methyl group, or an ethyl group. c may be an integer of 1 to 8, 1 to 5, or 1 to 3. d may be an integer of 1 to 8, 1 to 5, or 1 to 3.

[0049] As the silane coupling agent having an epoxy group, those exemplified as the silane coupling agent X can be used.

[0050] [Sorbitan Compound A] The sorbitan compound A is a sorbitan compound having one or more hydroxy groups. The number of hydroxy groups in the sorbitan compound A may be two or more or three or more, or four or less or three or less.

[0051] The sorbitan compound A may have a polyoxyethylene group. When the sorbitan compound A has a polyoxyethylene group, the number of repeating units (oxyethylene groups) of the polyoxyethylene group 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.

[0052] The sorbitan compound A may be a sorbitan fatty acid ester compound, which is an ester of sorbitan and a fatty acid, such as caprylic acid, capric acid, lauric acid, myristic acid, pentadecylic acid, palmitic acid, margaric acid, stearic acid, oleic acid, vaccenic acid, and linoleic acid.

[0053] When the sorbitan compound A is a sorbitan fatty acid ester compound, the number of ester groups that the sorbitan compound A has may be 1 or more, 3 or less, or 2 or less.

[0054] The sorbitan compound A may be a sorbitan fatty acid ester compound having a polyoxyethylene group. Examples of the sorbitan fatty acid ester compound having a polyoxyethylene group include polyoxyethylene sorbitan monolaurate (e.g., TW-L120 and TW-L106 manufactured by Kao Corporation) and polyoxyethylene sorbitan monooleate (e.g., TW-O120 and TW-O106 manufactured by Kao Corporation).

[0055] The structure of synthetic product A is determined depending on the structure of silane coupling agent A and the structure of sorbitan compound A. Synthetic product A may contain, for example, a compound represented by any one of general formulas (4) to (6). Synthetic product A may contain a condensate of a compound represented by any one of general formulas (4) to (6), or may contain a condensate of a compound represented by any one of general formulas (4) to (6) and silane coupling agent A.

[0056] [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 independently represents a hydrogen atom or a monovalent organic group, and e represents an integer of 1 to 10.

[0057] [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 represents a hydrogen atom or a monovalent organic group, and f represents an integer of 1 to 10.

[0058] [In formula (6), R ６１ , R ６２ , and R ６３each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms; R ６４ represents a hydrogen atom or a monovalent organic group, g represents an integer of 1 to 10, and h represents an integer of 1 to 10.

[0059] In formula (4), R ４１ , R ４２ , and R ４３ may each independently be a hydrogen atom, a methyl group, or an ethyl group. ４４ and R ４５ may each independently represent a hydrogen atom or a structure derived from sorbitan compound A. e may be an integer of 1 to 8, 1 to 5, or 1 to 3.

[0060] In formula (5), R ５１ , R ５２ , and R ５３ may each independently be a hydrogen atom, a methyl group, or an ethyl group. ５４ may be a hydrogen atom or a structure derived from sorbitan compound A. f may be an integer of 1 to 8, 1 to 5, or 1 to 3.

[0061] In formula (6), R ６１ , R ６２ , and R ６３ may each independently be a hydrogen atom, a methyl group, or an ethyl group. ６４ may be a hydrogen atom or a structure derived from sorbitan compound A. g may be an integer of 1 to 8, 1 to 5, or 1 to 3. h may be an integer of 1 to 8, 1 to 5, or 1 to 3.

[0062] The compound A can be prepared, for example, by stirring a silane coupling agent A and a sorbitan compound A for 0.5 to 24 hours in an environment of 40 to 100° C. The mixing ratio of the silane coupling agent A to the sorbitan compound A may be 10 to 200 parts by mass, or 30 to 100 parts by mass, of the silane coupling agent A relative to 100 parts by mass of the sorbitan compound A.

[0063] The conditions for synthesizing the synthetic product A can be adjusted, for example, by changing the peak position that can be confirmed in an IR chart. Specifically, when the silane coupling agent A has an acid anhydride group, the peak of the acid anhydride group at 1780 cm －１ Peaks near 1850 cm －１ The progress of the synthesis reaction can be confirmed by the fact that the peak around 910 cm , which is the peak of the epoxy group, becomes smaller in the IR chart after synthesis. －１ The progress of the synthesis reaction can be confirmed by the fact that the peak of

[0064] From the viewpoint of achieving superior water resistance and moisture resistance of the anti-fogging film, the content of Compound A 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, or 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, or 40 parts by mass or less, relative to 100 parts by mass of the silica particles. The content of Compound A may be 1 to 100 parts by mass, 5 to 60 parts by mass, or 15 to 40 parts by mass, relative to 100 parts by mass of the silica particles.

[0065] From the viewpoint of achieving better water resistance and moisture resistance of the anti-fogging film, the content of Compound A 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, relative to 100 parts by mass of Silane Coupling Agent B described below. The content of Compound A may be 10 to 500 parts by mass, or 50 to 200 parts by mass, relative to 100 parts by mass of Silane Coupling Agent B described below.

[0066] From the viewpoint of achieving superior water resistance and moisture resistance of the anti-fogging film, the content of Compound A may be 1% by mass or more, 2% by mass or more, 3% by mass or more, or 4% by mass or more, and may be 40% by mass or less, 30% by mass or less, 28% by mass or less, or 26% by mass or less, based on the total amount of solids of the anti-fogging agent. The content of Compound A may be 1 to 40% by mass, or 4 to 26% by mass, based on the total amount of solids of the anti-fogging agent.

[0067] (Silane Coupling Agent B Having Polyether Group) From the viewpoint of compatibility, the antifogging agent of the present embodiment may further contain a silane coupling agent B having a polyether group (hereinafter, this silane coupling agent may also be referred to as “silane coupling agent B”).

[0068] The silane coupling agent B may be a compound represented by the following general formula (7).

[0069] [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 independently represents an alkylene group having 1 to 6 carbon atoms, and k represents an integer of 3 to 25.

[0070] R ７１ , R ７２ , R ７３ and R ７４ may be a methyl group, an ethyl group, a propyl group, or a butyl group. ７１ and L ７２ may be an ethylene group, a propylene group, or a butylene group. k may be 10 to 20, or 11 to 15.

[0071] Examples of the silane coupling agent represented by the general formula (7) include A1230 (manufactured by Momentive Performance Materials Co., Ltd.) and X-12-641 (manufactured by Shin-Etsu Chemical Co., Ltd.).

[0072] From the viewpoint of compatibility, the content of silane coupling agent B may be 1 part by mass or more, 5 parts by mass or more, 8 parts by mass or more, or 10 parts by mass or more, and may be 50 parts by mass or less, 40 parts by mass or less, 30 parts by mass or less, or 20 parts by mass or less, relative to 100 parts by mass of silica particles. The content of silane coupling agent B may be 1 to 50 parts by mass, or 8 to 30 parts by mass, relative to 100 parts by mass of silica particles.

[0073] From the viewpoint of compatibility, the content of silane coupling agent B 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, or 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, relative to 100 parts by mass of compound A. The content of silane coupling agent B may be 10 to 500 parts by mass, or 50 to 300 parts by mass, relative to 100 parts by mass of compound A.

[0074] The content of silane coupling agent B may be 1% by mass or more, 3% by mass or more, 5% by mass or more, or 7% by mass or more, and may be 30% by mass or less, 20% by mass or less, 15% by mass or less, or 13% by mass or less, based on the total amount of solids in the antifogging agent. The content of silane coupling agent B may be 1 to 30% by mass, or 5 to 15% by mass, based on the total amount of solids in the antifogging agent.

[0075] (Other Silane Coupling Agents) The antifogging agent of the present embodiment may contain a silane coupling agent other than the above-mentioned silane coupling agent X and silane coupling agent B. Examples of such silane coupling agents include silane coupling agents having a C1 to C30 branched or linear alkyl group, a C3 to C10 cycloalkyl group, a C6 to C10 aryl group, or a fluoro group.

[0076] Examples of silane coupling agents having a C1 to C30 branched or linear alkyl group include methyltrimethoxysilane (KBM-13 manufactured by Shin-Etsu Chemical Co., Ltd., etc.), ethyltrimethoxysilane, propyltrimethoxysilane (KBM-3033 manufactured by Shin-Etsu Chemical Co., Ltd., etc.), butyltrimethoxysilane, pentyltrimethoxysilane, hexyltrimethoxysilane (KBM-3063 manufactured by Shin-Etsu Chemical Co., Ltd., etc.), heptyltrimethoxysilane, octyltrimethoxysilane, nonyltrimethoxysilane, decyltrimethoxysilane (KBM-3103C manufactured by Shin-Etsu Chemical Co., Ltd., etc.), undecyltrimethoxysilane, dodecyltrimethoxysilane, and tetradecyltrimethoxysilane. , stearyltrimethoxysilane, methyltriethoxysilane (KBE-13 manufactured by Shin-Etsu Chemical Co., Ltd., etc.), ethyltriethoxysilane, propyltriethoxysilane (KBE-3033 manufactured by Shin-Etsu Chemical Co., Ltd., etc.), butyltriethoxysilane, pentyltriethoxysilane, hexyltriethoxysilane (KBE-3063 manufactured by Shin-Etsu Chemical Co., Ltd., etc.), heptyltriethoxysilane, octyltriethoxysilane (KBE-3083 manufactured by Shin-Etsu Chemical Co., Ltd., etc.), nonyltriethoxysilane, decyltriethoxysilane, undecyltriethoxysilane, dodecyltriethoxysilane, tetradecyltriethoxysilane, and stearyltriethoxysilane.

[0077] Examples of silane coupling agents having a C6 to C10 aryl group include phenyltrimethoxysilane (KBM-103, KBM-202SS, KBE-103, KBE-202, etc., manufactured by Shin-Etsu Chemical Co., Ltd.), p-styryltrimethoxysilane (KBM-1403, etc., manufactured by Shin-Etsu Chemical Co., Ltd.), and the like.

[0078] Examples of silane coupling agents having a fluoro group include 3,3,3-trifluoropropyltrimethoxysilane (KBM-7103 manufactured by Shin-Etsu Chemical Co., Ltd.).

[0079] (Binder Compound) The antifogging agent of the present embodiment may further contain a binder compound. The binder compound refers to a compound that improves the strength of the antifogging film by bonding with silica particles and crosslinking. Examples of binder compounds include epoxy compounds, polyvinyl alcohol, modified polyvinyl alcohol, polyacrylic acid, acrylic resins, epoxy resins, urethane resins, polyvinylpyrrolidone, polyvinylpyrrolidone-vinyl acetate copolymers (vinyl acetate pyrrolidone copolymers), polyamine resins, cellulose, dextrin, cellulose nanofibers, silicate oligomers, and silicate polymers. The binder compounds can be used alone or in combination of two or more.

[0080] The binder compound may be an epoxy compound from the viewpoint of providing an anti-fog film with excellent fogging resistance. Examples of the epoxy compound 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.

[0081] 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.).

[0082] The content of the binder compound may be 0.1 to 1000 parts by mass, 0.5 to 500 parts by mass, or 1 to 100 parts by mass relative to 100 parts by mass of silica particles, from the viewpoint of obtaining better water resistance and moisture resistance of the anti-fogging film.

[0083] From the viewpoint of achieving better water resistance and moisture resistance of the anti-fogging film, the content of the binder compound may be 0.1 to 30 mass %, 0.3 to 20 mass %, or 0.5 to 10 mass %, based on the total amount of the solid content of the anti-fogging agent.

[0084] (Metal Catalyst) The antifogging agent of the present embodiment may further contain a metal catalyst. The metal catalyst functions as a bonding promoter, and when the antifogging agent contains a metal catalyst, it becomes easier to form an antifogging film that is excellent in moisture resistance and water resistance.

[0085] The metal catalyst is not particularly limited and can be selected from known metal catalysts, such as zirconium compounds, titanium compounds, nickel compounds, aluminum compounds, and tin compounds.

[0086] The metal catalyst may be a zirconium compound, an aluminum compound, or a nickel compound, from the viewpoint of providing the anti-fogging film with better moisture resistance and water resistance. When the anti-fogging agent contains at least one selected from the group consisting of a zirconium compound and an aluminum compound as the metal catalyst, the number of bonding points with silica particles (e.g., colloidal silica) increases, making it easier to form stronger bonds.

[0087] The metal catalyst may be a commercially available product.

[0088] The antifogging agent according to this embodiment may contain additives such as antioxidants, ultraviolet absorbers, and light stabilizers. In addition to acetic acid, the antifogging agent may also contain, as an antifoaming agent, catalyst, and the like used in preparing the raw materials, nitric acid, hydrochloric acid, nitric acid, phosphoric acid, sulfate, paratoluenesulfonic 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, and the like. The antifogging agent may contain a thickener to adjust the viscosity of the antifogging agent.

[0089] The antifogging agent may be a non-surfactant type. "Non-surfactant type" means that the content of a surfactant known as a component of the antifogging agent is 1 mass % or less based on the total amount of solids in the antifogging agent. The antifogging agent may not contain a surfactant (the content of the surfactant may be substantially 0 mass parts based on the total amount of solids in the antifogging agent). Examples of surfactants include anionic surfactants, cationic surfactants, nonionic surfactants, and amphoteric surfactants.

[0090] (Liquid Medium) The antifogging agent may contain a liquid medium. The liquid medium may be a medium that disperses silica particles in the antifogging agent, dissolves silane coupling agent X, polyether compound Y, synthetic substance A, silane coupling agent B, etc. The boiling point of the liquid medium may be 185°C or lower, from the viewpoint that the liquid medium volatilizes when heated during antifogging film formation, bringing silica particles closer to each other and facilitating the formation of bonds between the silica particles. The liquid medium may be the same as or different from the dispersion medium contained in the dispersion of silica particles.

[0091] Examples of the liquid medium include water, organic solvents, and mixtures thereof. Examples of the organic solvent 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.

[0092] <Anti-fogging method for vehicle lamp structure> The anti-fogging agent according to this embodiment can be used for anti-fogging a vehicle lamp structure. The anti-fogging method for a vehicle lamp structure may include, for example, a step of applying an anti-fogging agent to the inner surface of a lens included in the vehicle lamp structure to form a coating film (a coating step), and a step of drying the coating film (a drying step). Prior to the coating step, a cleaning step may be further included for the purpose of removing a release agent adhering to the surface of the lens.

[0093] (Cleaning Step) The cleaning liquid used in the cleaning step is not particularly limited. When the surface substrate in the lens of the vehicle lamp structure is polycarbonate, any liquid that does not dissolve the polycarbonate substrate may be used, for example, water, alcohols, etc. More specifically, water, isopropyl alcohol, methanol, ethanol, etc. may be used. The cleaning step may include a step of wiping the substrate with a cloth or the like soaked in the cleaning liquid.

[0094] (Coating Step) The coating step is, for example, a step of coating an antifogging agent on the inner surface of a lens provided in the vehicle lamp structure. The antifogging agent may be coated on the entire inner surface of the lens, or may be selectively coated on a portion thereof.

[0095] The method for applying the antifogging agent is not particularly limited, and may be, for example, spin coating, dip coating, spray coating, flow coating, bar coating, gravure coating, etc. The antifogging agent may be applied by impregnating a cloth or the like. The method for applying the antifogging agent may be spray coating, from the viewpoints of easily forming a coating film of uniform thickness even on uneven treated surfaces, high productivity, and high use efficiency of the antifogging agent. These methods may be used alone or in combination of two or more.

[0096] The amount of application is not limited because it depends on the components of the anti-fogging agent, the content thereof, etc., but for example, 10 －９ ~10 ３ g / m ２ may be.

[0097] The temperature of the antifogging agent used in the coating step may be, for example, 1 to 50° C., or 10 to 30° C. When the temperature of the antifogging agent is 1° C. or higher, the antifogging properties and adhesion are likely to be further improved, and when the temperature is 50° C. or lower, the transparency of the antifogging film is likely to be improved. The treatment time with the antifogging agent may be, for example, 1 second to 1 hour, or 5 to 30 minutes.

[0098] (Drying Process) The drying process may be a process in which the liquid medium is volatilized from the antifogging agent after application. The liquid medium can be volatilized by leaving it at room temperature (e.g., 20°C). By carrying out the drying process at a higher temperature, the adhesion between the inner surface of the lens and the antifogging film can be further improved. The temperature of the drying process can be adjusted depending on the heat resistance temperature of the lens, and may be, for example, 5 to 300°C or 10 to 200°C. A temperature of 5°C or higher can further improve adhesion, and a temperature of 300°C or lower can further suppress deterioration due to heat. The drying time can be 30 seconds to 150 hours. This process forms a silica-based antifogging film on the inner surface of the lens.

[0099] The thickness of the anti-fogging film is not particularly limited, but may be 100 nm to 1000 μm, 500 nm to 10 μm, or 1000 nm to 5 μm from the viewpoints of transparency, anti-fogging properties, etc. The film thickness of the anti-fogging film can be measured, for example, by an automatic film thickness measurement system F50 (manufactured by Filmetrics Inc.).

[0100] The water contact angle of the anti-fogging film can be 40° or less with respect to a 1 μL droplet of ultrapure water, and from the viewpoint of excellent anti-fogging properties, it may be 20° or less, or even 10° or less. The water contact angle can be calculated as the average value of 10 measurements using a contact angle meter.

[0101] The total light transmittance of the anti-fog film may be 80% or more, or 85% or more. When the total light transmittance of the anti-fog film is 80% or more, the brightness of the vehicle lamp can be maintained at a sufficiently high level. The visible light transmittance of the anti-fog film can be measured, for example, using a spectral haze meter SH 7000 (manufactured by Nippon Denshoku Industries Co., Ltd.).

[0102] The haze of the anti-fog film may be 4.0 or less, 3.0 or less, or 2.0 or less. When the haze of the anti-fog film is 4.0 or less, the brightness of the vehicle lamp can be maintained at a sufficiently high level. The haze of the anti-fog film can be measured, for example, using a spectroscopic haze meter SH 7000 (manufactured by Nippon Denshoku Industries Co., Ltd.).

[0103] The YI of the anti-fog film may be 4.0 or less, 3.0 or less, or 2.0 or less. When the YI of the anti-fog film is 4.0 or less, the brightness of the vehicle lamp can be maintained at a sufficiently high level. The YI of the anti-fog film can be measured, for example, using a spectroscopic haze meter SH 7000 (manufactured by Nippon Denshoku Industries Co., Ltd.).

[0104] FIG. 1 is a schematic diagram illustrating a vehicle lamp structure. The inner lens surface of the vehicle lamp structure is antifogging-treated using the antifogging agent according to this embodiment. That is, the vehicle lamp structure includes an antifogging film formed from the antifogging agent on the inner lens surface. The lamp structure 10 shown in FIG. 1 includes a lamp housing 3 configured as a recess with one open end and a lens 1 closing the open end of the lamp housing 3. The lens 1 is made of, for example, polycarbonate. The lamp housing 3 and the lens 1 form a lamp chamber S. A light source 4 is mounted in the lamp housing 3 and disposed within the lamp chamber S. The light source 4 may be an incandescent bulb, an LED bulb, a halogen bulb, or the like, as appropriate. As shown in the figure, a reflector 5 functioning as a reflector for the light from the light source 4 may be provided within the lamp chamber S so as to surround the light source 4 from the rear. The inner surface of the lens 1, i.e., the surface facing the lamp chamber S, is provided with an antifogging film 2 formed from the antifogging agent. The anti-fogging film 2 may be provided on the entire inner surface of the lens 1, or may be provided selectively on a portion thereof as shown in FIG.

[0105] <Hydrophilic Agent> The antifogging agent of the present embodiment can hydrophilize the surface of a substrate, and therefore can be called a hydrophilizing agent. The hydrophilized surface is less likely to lose its hydrophilicity even after a fogging test, and can form a good water film when moisture adheres to it. This makes it possible to prevent fogging on the substrate even in an environment where the substrate is exposed to volatile components. The treatment of the substrate can be carried out in the same manner as the antifogging method described above.

[0106] Examples of materials constituting the substrate include resin materials such as polycarbonate, acrylic polymer, polyamide, polyacrylate, polyimide, acrylonitrile-styrene copolymer, styrene-acrylonitrile-butadiene copolymer, polyvinyl chloride, polyethylene, and polycarbonate; metal materials such as aluminum, magnesium, copper, zinc, iron, titanium, chromium, manganese, cobalt, and nickel; inorganic materials such as silicon oxide, aluminum oxide, magnesium oxide, copper oxide, zinc oxide, iron oxide, titanium oxide, chromium oxide, manganese oxide, cobalt oxide, and nickel oxide; glass, etc. Examples of articles comprising such a substrate include the above-mentioned vehicle lamp structures (automotive headlights, etc.), as well as vehicle windshields, eyeglasses, goggles, mirrors, storage containers, windows, and camera lenses.

[0107] The present invention will now be described in more detail with reference to the following examples, but these examples are not intended to limit the scope of the present invention.

[0108] <Preparation of Synthetic Product A> (Synthetic Product 1) After obtaining a reaction solution containing 4.00 g of polyoxyethylene sorbitan monolaurate (manufactured by Kao Corporation, product name: TW-L120) and 1.28 g of a silane coupling agent having an acid anhydride group (manufactured by Shin-Etsu Chemical Co., Ltd., product name: X-12-967C), the reaction solution was charged into a reactor and stirred at 80°C for 1 hour. Thereafter, the reaction solution was cooled to room temperature to obtain Synthetic Product 1. IR charts before and after the synthesis of Synthetic Product 1 are shown in Figures 2 and 3. From Figures 2 and 3, it can be seen that the peak of the acid anhydride group in the IR chart before synthesis, 1780 cm －１ Nearby peaks and 1850cm －１ The disappearance of the peak at 1735 cm and the peak at 1735 cm in the IR chart before and after the synthesis confirmed that the synthesis reaction was progressing. －１ It was confirmed that the peak intensity around 1000 nm was higher after synthesis than before synthesis.

[0109] <Preparation of Anti-Fog Agent> (Example 1) 25.0 g of Snowtex O (manufactured by Nissan Chemical Industries, Ltd., concentration 20% by mass), 2.50 g of acetic acid, 0.50 g of a silane coupling agent (manufactured by Momentive, trade name: A1230), 5.0 g of a 10% by mass aqueous solution of Synthetic Product 1, 0.10 g of 3-glycidyloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., trade name: KBM403), 21.2 g of water, and 45.7 g of IPA were mixed and stirred for 2 hours to obtain a mother liquor.

[0110] A diluted solution was prepared by mixing 0.10 g of a 30% by mass aqueous solution of polyetheramine (manufactured by HUNTSUMAN Corporation, trade name: JEFFAMINEED-2003), 1.70 g of water, 49.10 g of IPA, and 15.80 g of ethylene glycol monobutyl ether. This diluted solution was mixed with the mother liquor to obtain a coating solution. The numbers shown in the table indicate the blending ratio (parts by mass) converted to solid content.

[0111] (Examples 2 to 6) A mother liquid and a diluted liquid were prepared so that KBM403 and ED-2003 were mixed in the proportions shown in Table 1, and a coating liquid was obtained in the same manner as in Example 1. In preparing the mother liquid, the amounts of water and IPA mixed were adjusted so that the mass ratio of water to IPA in the mother liquid was 1:1.

[0112] Example 7 A coating solution was obtained in the same manner as in Example 1, except that a 10% by mass aqueous solution of polyetheramine (manufactured by HUNTSUMAN Corporation, trade name: JEFFAMINEED-900) was used instead of the 30% by mass aqueous solution of ED-2003, and a mother liquor and a diluted solution were prepared so that KBM403 and ED-900 had the blending ratios shown in Table 2. In preparing the mother liquor, the blending amounts of water and IPA were adjusted so that the mass ratio of water to IPA in the mother liquor was 1:1.

[0113] Comparative Example 1 A coating solution was obtained in the same manner as in Example 1, except that the 30% by mass aqueous solution of ED-2003 and 3-glycidyloxypropyltrimethoxysilane were not blended, and the mother liquid and the diluted liquid were prepared so as to have the blending ratios shown in Table 2.

[0114] <Formation of anti-fogging film on polycarbonate substrate> A polycarbonate substrate measuring 10 cm square and 2 mm thick was cleaned with isopropyl alcohol. The coating solution obtained in the examples was applied to the substrate using an applicator or a spray, and the substrate was heated at 110°C for 30 minutes to obtain a polycarbonate substrate with an anti-fogging film having a thickness shown in Tables 1 and 2 as a test material.

[0115] <Evaluation> The following evaluations were carried out on the initial test material, the test material after the water resistance test described below, and the test material after the humidity resistance test described below. The anti-fogging index AFI was calculated for the initial test material and the test material after the humidity resistance test described below, and the water film uniformity index WE was calculated for the initial test material. The results are shown in Tables 1 and 2.

[0116] (Breath test) In a laboratory at a room temperature of 25° C., breath was blown onto the anti-fogging film of the test material from a position 5 cm away, and the presence or absence of fogging was visually observed. If no fogging occurred, it was rated as "A", and if fogging occurred, it was rated as "B".

[0117] (Anti-Fog Index) Using the device shown in Fig. 4, an image for evaluating anti-fogging properties and a reference image were obtained under the following photographing conditions. Using the obtained evaluation image and reference image, the anti-fogging index AFI was calculated by the calculation method shown below.

[0118] [Imaging conditions] Sample image: checkerboard pattern of black and white squares, square side length 0.5 mm Water temperature: 40 ° C. Distance D1: 1.5 cm Depth D2: 1 cm Distance D3: 17 cm (distance from sample image to the central surface of the front lens) Digital camera: Canon PowerShot SX70 HS (focal length in 35 mm film equivalent: 15 mm, saved image: size 1824 x 1824 pixels, saved format jpg), captured so that 4900 squares are included in the 1824 x 1824 pixel image. Anti-fogging evaluation image: taken 10 seconds after placing the test material. Reference image: taken immediately after placing a polycarbonate substrate not treated with an anti-fogging agent (0 seconds after placement) (image O) and after 10 seconds (image N). Compression method: resized to 820 x 820 pixels and output at a compression rate of 20%.

[0119] [Calculation of Antifogging Index AFI] The antifogging index AFI was calculated from the file size S1 when the image for evaluating antifogging properties was compressed using the above compression method, the file size S2 when image N was compressed using the above compression method, and the file size S0 when image O was compressed using the above compression method, using the following formula: AFI = (S1 - S2) x 10 / (S0 - S2).

[0120] (Water Film Uniformity Index) Evaluation images and reference images were obtained under the following photographing conditions using the device shown in Fig. 4. The obtained evaluation images and reference images were subjected to the image processing described below to calculate the water film uniformity index WE.

[0121] [Imaging conditions] Sample image: checkerboard pattern of black squares and white squares, square side length 0.5 mm Water temperature: 40 ° C. Distance D1: 1.5 cm Depth D2: 1 cm Distance D3: 17 cm (distance from sample image to the central surface of the front lens) Digital camera: Canon PowerShot SX70 HS (focal length in 35 mm film equivalent: 15 mm, saved image: size 1824 x 1824 pixels, saved format jpg), captured so that 4900 squares are included in the 1824 x 1824 pixel image. Evaluation image: taken 40 seconds after placing the test material. Reference image: taken immediately after placing a polycarbonate substrate not treated with an anti-fog agent (0 seconds after placement).

[0122] [Image Processing] (1) Using image processing software (ImageJ), read the evaluation image and the reference image and convert them to 8 bits (Image → type → 8 bit). (2) Set the boundary threshold to "90 to 255" (Image → Adjust → Threshold → Set to "90 to 255" → apply). (3) Binarize (Process → Binary → Make Binary). (4) Set "Area" as the measurement condition (Analyze → Set Measurements → Check Area). (5) Using particle analysis, calculate the area of ​​1 pixel square or more (Analyze → Analyze Particles → Set "Size" to "1-Infinity" and "Show" to "Outlines", check "Display results" and "Clear Results", and click OK). (6) From the information in (5) of the reference image, create a frequency distribution in 20 pixel increments in the range of 0 to 1000 pixels as the area distribution, and obtain the area range RA where the frequency is 5% or more of the total frequency. (7) From the information in (5) of the evaluation image, create a frequency distribution in 20 pixel increments in the range of 0 to 1000 pixels as the area distribution, and calculate the ratio (%) of the number of particles (frequency) included in the area range in (6) to the total number of particles (total frequency), and this is the water film uniformity index WE.

[0123] (Water Resistance Test) A test material was immersed in pure water and placed in a thermostatic chamber at 40° C., and was kept therein for 120 hours, and then left to stand at room temperature for one day.

[0124] (Moisture Resistance Test) The test material was placed in a thermostatic chamber at 50° C. and kept at a humidity of 95% for 120 hours, and then left to stand at room temperature for one day.

[0125]

[0126]

[0127] REFERENCE SIGNS LIST 1...lens, 2...anti-fogging film, 3...lamp housing, 4...light source, 5...reflector, S...lamp chamber, 10...lamp structure

Claims

1. An anti-fogging agent comprising silica particles, a silane coupling agent X having a reactive group X, and a polyether compound Y having two or more reactive groups Y capable of reacting with the reactive group X to form a bond.

2. 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 (however, two or more reactive groups Y may be the same or different).

3. The antifogging agent of claim 1, wherein said reactive group X is an epoxy group and said reactive group is an amino group.

4. The antifogging agent according to claim 1, further comprising a synthetic product A obtained by reacting a silane coupling agent A having an acid anhydride group or an epoxy group with a sorbitan compound having a hydroxyl group.

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

6. The antifogging agent according to claim 4, further comprising a silane coupling agent B having a polyether group.

7. An anti-fogging method for a vehicle lamp structure, comprising the steps of: applying the anti-fogging agent according to any one of claims 1 to 6 to the inner surface of a lens of the vehicle lamp structure to form a coating film; and drying the coating film.

8. A vehicle lamp structure comprising an anti-fogging film formed from the anti-fogging agent according to any one of claims 1 to 6 on an inner surface of a lens.

Images