JP2002166506A - Hydrophobic base material and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hydrophobic base material having excellent water repellency, waterdrop removing properties and waterdrop mobility and holding the effect of them over a long period of time. SOLUTION: In the hydrophobic base material, at least two surface treatment layers are provided on a transparent base material. The first layer as the uppermost layer of the surface treatment layers contains a surface treatment agent containing a specific polysiloxane compound such as (CH3)SiO(Si(CH3)2O)46 Si(CH3)2(CH2)2Si(OCH3)3 or the like as an essential component, and the second layer as in contact with the first layer contains a surface treatment agent containing other specific polysiloxane compound such as (CH3)3SiO(Si(CH3)2O)10 Si(CH3)2(CH2)2Si(OCH3)3 or the like as an essential component.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydrophobic substrate having a surface treatment layer having excellent "water repellency", "removability of water droplets" and "movability of water droplets", and a method for producing the substrate. More particularly, the present invention relates to a hydrophobic substrate having a surface treatment layer having the above-mentioned excellent properties and a method for producing the substrate, which can be suitably used for a window glass or a mirror of a vehicle or the like.

Here, "water repellency", "removability of water droplets" or "movability of water droplets" will be described. "Water repellency"
It is defined as a word representing "water repelling property". In the present invention, “water repellency” is evaluated based on the contact angle of water on the surface of the substrate. The surface having a large contact angle is a surface excellent in “water repellency”. “Water drop removability” is defined as a word representing “the property of water drops adhering to a surface sliding down and being removed”. In the present invention, a predetermined amount of water droplets is dropped on the surface of a horizontally held substrate, and the “water droplet removability” is evaluated at an angle at which the water droplets start sliding when the substrate is gradually tilted (hereinafter referred to as “sliding angle”). The surface having a small sliding angle is a surface having excellent "water droplet removal property".

[0003] "Water drop mobility" is defined as a word that expresses "the property that attached water drops move quickly on the surface". Water droplets dropped on the surface of the substrate held at a predetermined angle are accelerated to a certain speed and then slide down at a constant terminal speed. In the present invention, the “water droplet mobility” is evaluated based on the average speed of the water droplets in the specified section at this time (hereinafter referred to as “water droplet sliding speed”). The surface having a high water droplet sliding speed is a surface excellent in “water droplet mobility”. "Water repellency", "water droplet removal" or "water droplet mobility" must be separately discussed, and will be described by taking a window glass for an automobile as an example. It is not preferable that water droplets adhere to the outside of the window glass for an automobile because it may obstruct the driver's view. On the surface of glass with excellent "water repellency",
The water partially becomes small droplets and adheres to the surface. It is not easy to secure a view in a region where water droplets adhere, but it is easy to secure a view in a region where water droplets do not adhere. On the surface of the glass excellent in “water droplet removal property”, the attached water droplet falls spontaneously due to the inclination of the glass, and almost no water droplet remains on the surface of the glass, so that it is easy to secure the view.
On the surface of the glass excellent in “water droplet mobility”, the attached water droplets move quickly, so that the time during which the visibility is hindered by the presence of the water droplets is short. As described above, the window glass for an automobile having excellent "water repellency", "removability of water droplets" or "movability of water droplets" has an effect of facilitating securing a driver's view by different principles. As window glass for automobiles,
It is preferable to have all of "water repellency", "water droplet removability" and "water droplet mobility".

[0004]

2. Description of the Related Art A water-repellent coating made of a silicone compound having a hydrolyzable functional group has been proposed in order to impart water repellency, water droplet removability and water droplet mobility to the surface of a substrate.
However, for example, a water-repellent coating composed of a composition containing a polydimethylsiloxane compound having a functional group at one end and a silane coupling agent, which is proposed in JP-A-11-315276, is referred to as "water-repellent", Although it has both "water droplet removal" and "water droplet mobility", their durability was not sufficient.

[0005]

SUMMARY OF THE INVENTION The present invention relates to "water repellency",
An object of the present invention is to provide a hydrophobic base material which is excellent in "water droplet removal property" and "water droplet mobility" and whose effects are maintained for a long period of time.

[0006]

The present invention provides a hydrophobic substrate having at least two surface treatment layers on a base substrate, wherein the first layer, which is the outermost layer of the surface treatment layer, comprises the following compound ( A layer containing a surface treatment agent (A) containing A) as an essential component, and a second layer in contact with the first layer is a layer containing a surface treatment agent (B) containing the following compound (B) as an essential component. A surface-treated hydrophobic substrate is provided. Compound (A): a compound represented by the following formula (A) and / or a hydrolysis product thereof.

[0007]

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[0008] (R ¹ is an organic group having 1 to 20 carbon atoms, R ² is methyl, R ³ is a methyl group or an ethyl group, X is a hydrolyzable group, p is 2 or 3, q is 0, 1 or 2, n is 1 to
Indicates an integer of 100. When two or more X and R ³ are present, they may be the same or different. Compound (B): a compound represented by the following formula (B) and / or a hydrolysis product thereof.

[0009]

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(R ¹ , R ² , R ³ , X, p, and q have the same meanings as defined in formula (A), and may be the same as or different from those in formula (A). Is 1 to 10
Indicates an integer of 0. However, n <m is satisfied. )

The at least two surface treatment layers in the present invention do not need to be in a state in which the boundaries are strictly understood, and some or all of the interfaces between the layers may be intermingled.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Surface treatment agent (A) in the present invention
Alternatively, the surface treatment layer formed by applying the surface treatment agent (B) exhibits good "water repellency", "water droplet removal property" and "water droplet mobility" alone. However, by adopting the configuration proposed by the present invention, the sustainability of the effect can be drastically improved, and the effect exceeds the level expected when these materials are laminated. Although the detailed mechanism of the effect of the present invention is unknown, appropriate mixing (interdiffusion) between the material constituting the first layer and the material constituting the second layer is achieved by combining specific materials. Happen
It is considered that the denseness and the film forming property of the entire layer are improved, and the durability of the effect is enhanced. That is, by forming a layer excellent in denseness and film forming property, surface energy can be reduced, surface smoothness can be improved, and various deterioration factors can be prevented from diffusing into the layer. Therefore, it is considered that excellent "water repellency", "water droplet removability" and "water droplet mobility" can be maintained for a long time.

In the present invention, the surface treated with the surface treatment agent (A) refers to the first surface in which the compound (A) contained in the surface treatment agent (A) is chemically or physically bonded to the surface of the second layer. Refers to the surface of the layer. The compound (A) is a compound having a reactive group, and it is considered that the compound (A) binds to the surface of the second layer mainly by a chemical reaction. That is,
In the bonded state, the reactive group of compound (A) is considered to have changed. The surface treated with the surface treatment agent (B) in the present invention refers to the surface of the second layer in which the compound (B) contained in the composition (B) is chemically or physically bonded to the surface of the substrate. . Since the compound (B) has a reactive group, it is considered that the compound (B) is mainly bonded to the surface of the substrate by a chemical reaction. That is, in the binding state, the reactive group of the compound (B) is considered to have changed.

The compound (A) or compound (B) in the present invention is a linear polydimethylsilicone compound having a hydrolyzable group at one molecular terminal. As similar materials, (a) a compound in which a hydrolyzable group is located in a molecular chain instead of a molecular terminal, (b) a compound in which a polydimethylsilicone moiety has a branched structure instead of a linear structure,
(C) Compounds in which a part of the methyl group of the polydimethylsilicone site is substituted with another functional group are conceivable. However, in the compounds corresponding to (a) to (c), good "water repellency" is obtained, but sufficient "water droplet removal" and "water droplet mobility" are not obtained. Although the mechanism is not sufficiently clear, in the compounds corresponding to (a) to (c), the space occupied by one molecule is larger than that in the polydimethylsilicone compound having a linear structure. It is estimated that it does not increase. On the other hand, a compound having a structure similar to that used in the present invention and having a hydrolyzable group at both ends provides good “water repellency”, but has sufficient “water droplet removal properties” and “water droplet migration”. Sex cannot be obtained. This is because polar portions such as unreacted hydrolyzable groups or residues after the reaction of hydrolyzable groups (for example, oxygen atoms) are likely to remain on the surface of the membrane due to the presence of hydrolyzable groups at both ends. Conceivable.

The molecular chain length of the compound (A) or compound (B) in the present invention (n or m, which is the number of repeating units)
Is long, the workability deteriorates, so both n and m are 1 to 1
00. In order to exhibit the effect of the present invention, the second layer which is in contact with the first layer is less than the compound forming the first layer which is the outermost layer.
It is necessary that the compound forming the layer has a larger number of repeating units. That is, n <m is satisfied. When n> m, the interdiffusion between the first layer and the second layer is not effectively performed, and the film simply becomes a film in which two compounds are laminated, and has no durability. In the present invention, the number of repeating units n of the compound (A) is preferably from 5 to 15 in order to further enhance the persistence of “water repellency”, “removability of water droplets” and “water droplet mobility”. The number m of repeating units is preferably 30 to 60.

R ¹ in the compound (A) or the compound (B) is independently an organic group having 1 to 20 carbon atoms, preferably an alkyl group, a cycloalkyl group or an aryl group having 1 to 20 carbon atoms. Alkyl groups having the numbers 1 to 20 are particularly preferred. The alkyl group may have an etheric oxygen atom or a thioetheric sulfur atom inserted therein. R ¹ is preferably an alkyl group having 1 to 8 carbon atoms. Particularly, a methyl group is preferable. X is preferably a halogen atom, a hydroxy group, an alkoxy group, or an isocyanate group. The number (3-q) of the hydrolyzable groups in the compound (A) or the compound (B) is preferably larger as the number is larger, since the adhesion to a substrate or the like becomes higher. (3-q)
Is preferably 2 or 3.

Surface treatment agent (A) or surface treatment agent (B)
May be used only in the form of compound (A) or compound (B), which is an essential component thereof, but may be used in a form diluted with an organic solvent in consideration of workability, film thickness, treatment method and the like. Is preferred. The organic solvent is not limited as long as it dissolves essential components, but alcohols, esters, ketones, aromatic hydrocarbons, and paraffin hydrocarbons are preferable, and particularly preferably, ethyl alcohol,
Lower alcohols such as isopropyl alcohol or acetates. The organic solvent to be used is not limited to one kind, and two or more kinds of organic solvents having different polarities, evaporation rates, and the like can be used as a mixture. The amount of the organic solvent used is preferably such that the ratio of the compound (A) or the compound (B) is 0.1 to 30% by mass, from the viewpoint of the stability of the treating agent or the economic efficiency. Compound (A) or compound (B) is
For the purpose of increasing the durability of the obtained layer, a hydrolysis product by water, an acid or an alkali, or a hydrolysis product by a polycondensation reaction may be used. There is no limitation on acid or alkali,
What is necessary is just to select suitably according to the objective. As the acid, sulfuric acid,
Hydrochloric acid, nitric acid, phosphoric acid, acetic acid, formic acid and the like are preferable, and as the alkali, ammonia, sodium hydroxide, potassium hydroxide and the like can be preferably used. Acids or alkalis
It may be used as it is, or may be used in the form of an aqueous solution thereof for the purpose of accelerating the reaction. The amount of the acid or alkali used is preferably 0.05 to 30 parts by mass with respect to 100 parts by mass of the compound (A) or the compound (B). If the amount is less than 0.05 part by mass, the effect of the addition is not exhibited, and if the amount exceeds 30 parts by mass, a problem may occur in the stability of the surface treating agent.

In the treatment of the surface of the second layer with the surface treating agent (A), no special pretreatment is required. It is preferable to form the first layer immediately after forming the second layer. The layer is formed by applying the surface treatment agent (A) by a known method, for example, brushing, flow coating, spin coating, dip coating, squeegee coating,
It is preferable to apply by a method such as spray coating or hand coating, and to dry in the air or in a nitrogen stream. When excess components are generated and the appearance is impaired, the appearance may be adjusted by wiping with a solvent or wiping with an empty cloth to remove the excess components. The thickness of the first layer is not particularly limited, but is preferably 50 nm or less from the viewpoint of economy, and the lower limit is the monolayer thickness. In the treatment of the surface of the substrate with the surface treating agent (B), no special pretreatment is required. The layer is preferably formed in the same manner as in the case of the surface treatment agent (A). The thickness of the second layer is not particularly limited, but is preferably 100 nm or less from the viewpoint of economy, and the lower limit is the monolayer thickness.

Surface treatment agent (A) or surface treatment agent (B)
May be added according to the purpose. The additive may be selected in consideration of reactivity or compatibility with the compound (A) or the compound (B), and may be selected from other water-repellent materials (such as a polyfluoroalkyl group-containing organosilicon compound), silica, alumina, Ultrafine particles of various metal oxides such as zirconia and titania, and various resins are preferably exemplified. Further, a photocatalyst may be added for the purpose of imparting antifouling properties,
Dyes or pigments may be added for the purpose of coloring. The amount of the additive is preferably 0.01 to 20% by mass in the surface treatment agent (A) or the surface treatment agent (B). Excessive addition is not preferred because it reduces the durability of "water repellency", "water droplet removal" and "water droplet mobility" of the present invention.

The hydrophobic substrate of the present invention may be formed by directly applying the surface treating agent (B) to the base substrate to form a layer. A stratum may be formed. As this underlayer, SiY ₄
The layer containing the composition (C) containing the compound represented by the formula (1) and / or a hydrolysis product thereof as an essential component is preferable.
Here, Y is a halogen atom, a hydroxy group, an alkoxy group or an isocyanate group, and the four Ys may be the same or different. As the acid or alkali used for producing the hydrolysis product, the compounds described in the description of the compound (A) or the compound (B) are preferably exemplified. It is also preferable to add a metal oxide other than silica or a precursor compound thereof to the compound (C) to form a mixed oxide layer or a composite oxide layer. As the composition (C), a compound (C) diluted with an organic solvent is preferable. The composition (C) may contain additives other than the organic solvent. As the organic solvent, the organic solvents described for compound (A) or compound (B) can be preferably used.
Preferred examples of the additives include fillers such as the above-mentioned metal oxide ultrafine particles, binder components, and surfactants. The amount of the additive or the amount of the organic solvent used is preferably the same as that of the compound (A) or the compound (B).

The formation of the underlayer is preferably carried out by applying the composition (C) by a known method and drying it at room temperature or by heating in the air or in a nitrogen stream. Room temperature is sufficient for drying, but when heating, the temperature, time, etc. may be set in consideration of the heat resistance of the base material. Although the thickness of the underlayer is not particularly limited, when the base material is soda lime glass, the thickness may be 50 nm or more for the purpose of preventing the elution of Na ions. However, if the thickness is too large, the damage becomes noticeable, so that the thickness is preferably 100 nm or less. The lower limit is the monolayer thickness. The thickness of the entire surface treatment layer can be controlled by the concentration of the surface treatment agent (A), the surface treatment agent (B) or the composition (C), application conditions, heating conditions, and the like. In view of economy, the thickness is preferably 500 nm or less, particularly preferably 100 nm or less. No special pretreatment is required for forming the surface treatment layer or the underlayer. However, pretreatment may be performed according to the purpose, for example, diluted hydrofluoric acid,
Acid treatment with sulfuric acid, hydrochloric acid, etc., alkali treatment with sodium hydroxide solution or plasma irradiation, corona irradiation,
Discharge treatment by electron beam irradiation or the like may be performed.

The base material in the present invention is not particularly limited, but preferably includes metals, plastics, glasses, ceramics, other inorganic and organic materials, and combinations thereof (composite materials, laminated materials, etc.). The surface of the base substrate may already have some surface treatment layer. Further, the shape of the substrate is not limited to a flat plate,
Any shape, such as one having a curvature, may be used. As the base substrate, a substrate such as glass or plastic is preferable. The hydrophobic substrate of the present invention is a train, a bus, a truck, an outer plate in various vehicles such as an automobile, a window glass,
It can be suitably used for mirrors, display device surfaces, instrument panel surfaces, and the like. In particular, it is preferably used in a field of view such as a window glass. By using the hydrophobic substrate of the present invention, a window glass or the like excellent in “water repellency”, “water droplet removal property” and “water droplet mobility” can be obtained, whereby visibility can be easily secured and vehicle safety can be improved. Performance can be improved. Further, even in an environment where water droplets freeze, the ice does not freeze, and even if it freezes, thawing is remarkably fast. Furthermore, since there is almost no adhesion of water droplets, the number of regular cleaning operations can be reduced, and the cleaning operation is extremely easy, which is very advantageous from the viewpoint of aesthetic protection.

[0023]

EXAMPLES Various evaluation methods used in the examples are as follows. Table 1 shows the results. [Evaluation of water repellency] Approximately 3
μL of water was dropped, and the contact angle of the formed water droplet was measured. The water repellency was evaluated according to the following criteria. When the contact angle is 90 ° or more; ○ When the contact angle is less than 90 °; × [Evaluation of water droplet removal property] About 5 μL of water droplets was dropped on a sample substrate held horizontally. Next, the substrate is gradually tilted at a constant angular velocity, and the angle at which the water droplet starts to slide (sliding angle)
Was read. The water droplet removability was evaluated according to the following criteria. When the sliding angle is 10 ° or less; ◎ When the sliding angle is more than 10 ° and 20 ° or less; ○ When the sliding angle is more than 20 ° and 30 ° or less; △ When the sliding angle is more than 30 °; ×

[Evaluation of Water Drop Mobility] The sample substrate was held at an angle of 30 ° from the horizontal plane. Next, a water droplet of 10 μL was dropped on the sample substrate. When a dropped water drop slides down, the movement speed of the water drop is measured by measuring the time required to pass through a prescribed section (20 mm) on the sample substrate, and the water drop sliding speed (mm / sec) = the movement distance of the water drop (mm) ) / Time required for movement (sec). The water droplet mobility was evaluated based on the following criteria. When the water droplet movement speed is 0 (does not slide down) to less than 5 mm / sec; × When the water droplet movement speed is 5 mm / sec or more and less than 10 mm / sec;
△ When the water droplet movement speed is 10 mm / sec or more and less than 15 mm / sec; ○ When the water droplet movement speed is 15 mm / sec or more; ◎ [Evaluation of durability] Irradiation was performed for 96 hours using a super xenon meter (manufactured by Suga Test Instruments). Thereafter, "water repellency", "water droplet removal" and "water droplet mobility" were evaluated.

Example 1 2 g of tetraisocyanate silane was added to 98 g of n-butyl acetate, and the mixture was stirred at room temperature for 10 minutes to obtain a treating agent 1-3. 75 g of isopropyl alcohol
After adding 1.5 g of a 0.3% by mass aqueous solution of nitric acid to the mixture and stirring well, 5 g of the following compound a was added thereto and stirred for 10 minutes. Further, 20 g of a solution obtained by diluting silica sol (a product of Chisso Corporation, trade name “Rixon Coat CGS-D1-0600”) with isopropyl alcohol at a mass ratio of 60 times was added.
The mixture was stirred at room temperature for 10 minutes to obtain a treating agent 1-2. Treatment agent 1
In -2, a treating agent 1-1 was obtained in the same manner as the treating agent 1-2, except that the following compound b was used instead of the compound a. Treatment agent 1-3 is applied to glass substrate which has been washed beforehand.
Was applied dropwise in the manner of waxing automobiles, and then left at room temperature for 60 minutes. Next, treatment agent 1
-2 is applied in the same manner and left at room temperature for 1 minute.
The treating agent 1-1 was applied in the same manner. After leaving this substrate for one day, the surface was wiped off with a cotton cloth impregnated with isopropyl alcohol to obtain a sample substrate.

[0026]

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Example 2 A sample substrate was obtained in the same manner as in Example 1 except that the treating agent 1-3 was not applied.

Example 3 To 95 g of isopropyl alcohol was added 1.5 g of a 0.3% by weight aqueous solution of nitric acid, and the mixture was stirred well. To this, 5 g of compound a was added and stirred for 10 minutes to obtain a treating agent 3-2. In treating agent 3-2, a treating agent 3-1 was obtained in the same manner as in treating agent 3-2 except that compound b was used instead of compound a. In Example 1, a sample substrate was obtained in the same manner as in Example 1, except that the treating agent 3-2 was used instead of the treating agent 1-2 and the treating agent 3-1 was used instead of the treating agent 1-1. .

Example 4 5 g of the following compound c was added to 95 g of n-butyl acetate, and the mixture was stirred for 10 minutes to obtain a treating agent 4-2.
5 g of the following compound d was added to 95 g of n-butyl acetate, and the mixture was stirred for 10 minutes to obtain a treating agent 4-1. In Example 1, a sample substrate was obtained in the same manner as in Example 1 except that the treating agent 4-1 was used instead of the treating agent 1-2 and the treating agent 4-1 was used instead of the treating agent 1-1. .

[0030]

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Example 5 5 g of the following compound e was added to 95 g of n-butyl acetate, and the mixture was stirred for 10 minutes to obtain a treating agent 5-2.
5 g of the following compound f was added to 95 g of n-butyl acetate, and the mixture was stirred for 10 minutes to obtain a treating agent 5-1. In Example 1, a sample substrate was obtained in the same manner as in Example 1, except that the treating agent 5-2 was used instead of the treating agent 1-2 and the treating agent 5-1 was used instead of the treating agent 1-1. .

[0032]

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Example 6 A sample substrate was obtained in the same manner as in Example 2 except that the following compound g was used in place of compound a.

[0034]

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Example 7 A sample substrate was obtained in the same manner as in Example 2 except that Compound g was used instead of Compound b.

Example 8 A sample substrate was obtained in the same manner as in Example 3, except that the treatment using the treating agent 3-1 was not performed.

Example 9 A sample substrate was obtained in the same manner as in Example 3, except that the treatment using the treating agent 3-2 was not performed.

Example 10 A sample substrate was obtained in the same manner as in Example 3, except that the order of the treatment using the treatment agent 3-2 and the treatment using the treatment agent 3-1 were reversed. Was.

[0039]

[Table 1]

[0040]

According to the present invention, a hydrophobic group which has a surface treatment layer excellent in "water repellency", "removability of water droplets" and "water droplet mobility" and whose effects are maintained for a long period of time. Materials are provided.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) // C09D 183/02 C09D 183/02 183/10 183/10 183/14 183/14 C08L 101: 00 C08L 101: 00 (72) Inventor Nao Hamano 426-1, Ozawa Uehara, Kakuda Aikawa-cho, Aiko-gun, Kanagawa Prefecture Inside Asahi Glass Co., Ltd. (72) Inventor Yasuo Kai 2nd Takaracho, Kanagawa-ku, Yokohama City, Kanagawa Prefecture Inside Nissan Motor Co., Ltd. Tetsuro F-term (reference) 4F006 AA11 AA31 AB39 CA04 DA04 4F100 AH06A AH06K AK01A A 2 Takaracho, Kanagawa-ku, Yokohama-shi, Kanagawa Prefecture K52B AK52C AK52K AT00A BA03 BA07 BA10A BA10C EH462 GB07 GB31 GB51 JB06 JL00 4H020 BA32 4J035 BA02 CA071 LB01 LB07 4J038 DL021 DL031 DL131 DL161 GA16 KA06 MA14 NA07 PA18 PB06 PB07 PC02 PC03 PC04 PC0408

Claims (7)

[Claims] 1. A hydrophobic substrate having at least two surface treatment layers on a base substrate, wherein the first layer which is the outermost layer of the surface treatment layer contains the following compound (A) as an essential component: A layer containing the treating agent (A), wherein the second layer in contact with the first layer is a surface treating agent (B) containing the following compound (B) as an essential component
A hydrophobic substrate, characterized by being a layer containing: Compound (A): a compound represented by the following formula (A) and / or a hydrolysis product thereof. Embedded image (R ¹ is an organic group having 1 to 20 carbon atoms, R ² is a methyl group, R ³
Is a methyl or ethyl group, X is a hydrolyzable group, and p is 2
Or 3, q represents 0, 1 or 2, and n represents an integer of 1 to 100. When two or more X and R ³ are present, they may be the same or different. Compound (B): a compound represented by the following formula (B) and / or a hydrolysis product thereof. Embedded image (R ¹ , R ² , R ³ , X, p, and q have the same definitions as in the formula (A), and may be the same as or different from those in the formula (A). Indicates an integer of 100.
However, n <m is satisfied. ) 2. The hydrophobic substrate according to claim 1, wherein n in the compound (A) is 5 to 15, and m in the compound (B) is 30 to 60. Wherein R ¹ in the compound (A) and the compound (B) are both methyl groups, hydrophobic substrate according to claim 1 or 2. 4. The compound according to claim 1, wherein X in compound (A) and compound (B) is independently a halogen atom, a hydroxy group, an alkoxy group or an isocyanate group.
4. The hydrophobic substrate according to any one of 3. 5. The base material according to claim 1, wherein the base material has a layer containing a composition (C) containing the following compound (C) as an essential component.
The hydrophobic substrate according to any one of Items 1 to 4. Compound (C): a compound represented by the following formula (C) and / or a hydrolysis product thereof. Embedded image (Y is a halogen atom, a hydroxy group, an alkoxy group or an isocyanate group, and the four Ys may be the same or different.) 6. The method for producing a hydrophobic substrate according to claim 1, wherein a surface treatment agent (B) is applied to the surface of the base substrate to form a second layer. A method for producing a hydrophobic substrate, further comprising a step of applying a surface treatment agent (A) to the surface of the second layer to form an outermost layer. 7. The method according to claim 7, wherein the base material on which the surface treatment layer is formed is
The method for producing a hydrophobic substrate according to claim 6, further comprising a step of applying a layer containing the composition (C) containing the following compound (C) as an essential component in advance to form an underlayer.