JPH07252472A - Agent for water-repelling treatment - Google Patents

Abstract

PURPOSE:To obtain a water-repelling agent giving high water-repellency and stain-proofing property to a treating object by cohydrolyzlng anorganic Si compound containing perfluoroalkyl group and a methylpolysiloxane compound containing hydrolyzable group in water and a hydrophilic solvent and using the product as an essential component. CONSTITUTION:This water-repelling agent soluble in organic solvent can be produced by compounding a cohydrolysis product produced by hydrolyzlng (A) an organic silicon compound containing a perfluoroalkyl group and expressed by formula I (R<1> is a l-4C univalent hydrocarbon group; R<2> is a l-4C alkoxy or an acyloxy; Q is a 2-10C bivalent organic group; (a) is 0 or 1; (p) is an integer of 1-12) and (B) a methylpolysiloxane compound containing a hydrolyzable group and expressed by formula II [R<3> is a 1-4C univalent hydrocarbon group; R<4> is a 1-4C alkoxy or an acyloxy; A is methyl or group of formula III (Z is 0 or a 2-10C bivalent hydrocarbon group); b is 0, 1 or 2; m is an integer of 3-100; n is an integer of 0-50; 5<=m+n<=100; when n=0, at least one of the A groups at both ends is the group of formula III] in water and a hydrophilic solvent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic solvent-soluble water repellent treatment agent capable of imparting excellent water repellency and stain resistance to inorganic surfaces such as glass, ceramics and metals. In particular, it relates to a water repellent treatment agent capable of imparting self-cleaning property to an inorganic surface by rainwater.

[0002]

2. Description of the Related Art Conventionally, the problems to be solved by the invention
Various studies have been conducted to improve the properties of the surface of inorganic materials such as glass, ceramics, metals, etc. by treating them with various surface treatment agents to improve the performance and expand the range of application. As one of them, there has been proposed a method of treating an originally hydrophilic surface with a silicone composition to modify it into a water-repellent surface, and particularly, JP-A-58-147484 and JP-A-6-147484.
It is described in JP-A No. 0-212470 and JP-A No. 4-96935 that polysiloxane or polysilazane containing a perfluoroalkyl group is excellent in water repellency.

However, since the above-mentioned water repellent agent is excellent in water repellent effect but inferior in drop property of water drops, when applied as an antifouling agent for window glass of buildings such as houses and buildings, In some cases, water droplets did not fall and stayed like polka dots on the glass surface, which caused dust in the air, oil, etc., to adhere to the glass and contaminate it.

Further, Japanese Patent Laid-Open No. 3-290437 proposes a fluorine-containing silazane compound. Although this compound has improved the above-mentioned drawbacks, it has poor solubility in general organic solvents and is subject to CFC regulation. However, there is a problem that it is only soluble in fluorocarbons such as 1,1,3-trichlorotrifluoroethane and expensive fluorohydrocarbons, which limits the application range. .

The present invention has been made in view of the above circumstances.
It is excellent in water repellency-providing effect and water drop drop improving effect, and can impart excellent water repellency and antifouling property to the surface of the object to be treated,
Moreover, it is an object to provide a water-repellent treatment agent that is soluble in an organic solvent.

[0006]

Means and Actions for Solving the Problems As a result of intensive studies for achieving the above object, the present inventor has found that a perfluoroalkyl group-containing organosilicon compound represented by the following general formula (I) and the following general formula: It was found that the cohydrolyzate of the hydrolyzable group-containing methylpolysiloxane compound represented by (II) in water and a hydrophilic solvent has excellent properties as a water repellent treatment agent.

[0007]

[Chemical 3] (However, in the formula, R ¹ is a monovalent hydrocarbon group having 1 to 4 carbon atoms, R ² is an alkoxy group or acyloxy group having 1 to 4 carbon atoms, and Q is a divalent organic group having 2 to 10 carbon atoms. Is a group, a is 0 or 1, and p is an integer of 1 to 12.)

[0008]

[Chemical 4]

That is, in the co-hydrolyzate, the perfluoroalkyl group-containing organosilicon compound of the formula (I) is effective for imparting water repellency, and the hydrolyzable group-containing methylpolysiloxane compound of the formula (II) is water droplets. It has a silanol group that contributes to the falling property improvement effect of the two components and is highly reactive with the inorganic surface due to the cohydrolysis of these two components. Therefore, it has excellent water repellency and antifouling property on the surface of the object to be treated. In addition, it is possible to give a wide range of use because it is soluble in a hydrophilic solvent and does not require the use of a special fluorine-based solvent, and it is effective as a water repellent treatment agent. It has come.

Therefore, the present invention comprises a perfluoroalkyl group-containing organosilicon compound represented by the above general formula (I):
There is provided a water repellent treatment agent comprising a cohydrolyzate of a hydrolyzable group-containing methylpolysiloxane compound represented by the general formula (II) in water and a hydrophilic solvent.

The present invention will be described in more detail below. The first raw material of the water repellent agent of the present invention is a perfluoroalkyl group-containing organosilicon compound represented by the following general formula (I).

[0012]

[Chemical 5] (However, in the formula, R ¹ is a monovalent hydrocarbon group having 1 to 4 carbon atoms, R ² is an alkoxy group or acyloxy group having 1 to 4 carbon atoms, and Q is a divalent organic group having 2 to 10 carbon atoms. Is a group, a is 0 or 1, and p is an integer of 1 to 12.)

In the above formula (I), examples of R ¹ include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group and s-butyl group, and R ² includes For example, methoxy group, ethoxy group,
Examples thereof include n-propoxy group, isopropoxy group, isopropenoxy group, n-butoxy group and acetoxy group.
Q is a group that bonds a perfluoroalkyl group and a silicon atom, and examples thereof include a divalent hydrocarbon group or a divalent hydrocarbon group containing an oxygen atom, a nitrogen atom or a sulfur atom in the molecule,
Specifically _{-CH 2 CH 2 -, - CH} 2 OCH 2 CH 2 CH
_{2 -, - CONHCH 2 CH 2} CH 2 -, - CONHCH 2
_{CH 2 NHCH 2 CH 2 CH 2} -, - SO 2 NHCH 2 CH 2
_{CH 2 -, - CH 2 CH} 2 OCONHCH 2 CH 2 CH 2 - group and the like. Further, p represents the number of carbon atoms of the perfluoroalkyl group and is 1 to 12, and when p exceeds 12, the solubility in organic solvents deteriorates. a is 0 or 1.

Specific examples of the perfluoroalkyl group-containing organosilicon compound of the above formula (I) include the following compounds, and one of these compounds may be used alone or 2
A mixture of more than one type can be used.

[0015]

[Chemical 6]

Next, the hydrolyzable group-containing methylpolysiloxane compound as the second raw material is a compound represented by the following general formula (II).

[0017]

[Chemical 7]

Here, examples of R ³ include the same groups as those of R ^1, and examples of R ⁴ include the same groups of R ² . Examples of Z include the following groups (alkylene groups) as divalent hydrocarbon groups in addition to oxygen atoms.

[0019]

[Chemical 8]

Further, m is 3 to 100, preferably 5 to 5.
An integer of 0, n is an integer of 0 to 50, preferably 0 to 10 and 5 ≦ m + n ≦ 100, preferably 5 ≦ m + n ≦
When it is 60 and m + n is less than 5, the drop property of the above-mentioned water droplets is insufficient and the antifouling property is deteriorated, and when it exceeds 100, the stability of the cohydrolyzed product is deteriorated.

The perfluoroalkyl group-containing organosilicon compound of the above formula (I) and the hydrolyzable group-containing methylpolysiloxane compound of the formula (II) are mixed in a weight ratio of (I).
/ (II) is 10/90 to 90/10, especially 20/80
It is preferably -80/20. When the compounding ratio of the compound of the formula (I) is less than 10% by weight, sufficient water repellency may not be obtained, and when it exceeds 90% by weight, drop property of water droplets is insufficient and sufficient antifouling property cannot be obtained. .

Further, the hydrophilic solvent used for the co-hydrolysis of both the above compounds is not particularly limited as long as it can dissolve the compounds of the above formulas (I) and (II) and water, and examples thereof include methanol and ethanol. , Alcohols such as isopropanol and n-propanol, cellosolves such as methyl cellosolve, ethyl cellosolve, butyl cellosolve and cellosolve acetate, ketones such as acetone and methyl ethyl ketone, ethers such as dioxane and tetrahydrofuran, and the like. The amount of the hydrophilic solvent used is not particularly limited, but the concentration of the compounds of the formulas (I) and (II) is 1 to 30.
It is preferably in the range of wt%, particularly 3 to 15 wt%.

Water is used for the cohydrolysis, but the amount of water added is 0.5 equivalent or more based on the total amount of alkoxy groups and acyloxy groups contained in the compounds of formulas (I) and (II). In particular, 0.5 to 2 equivalents are suitable, and if the amount is less than 0.5 equivalents, the reactivity with the inorganic surface may be weak because the hydrolysis rate is insufficient. There may not be.

In the present invention, a small amount of acid may be added so that the pH of the system is less than 7, preferably pH 5 or less for the purpose of promoting the reaction during cohydrolysis. As the acid, hydrochloric acid,
Examples thereof include sulfuric acid, nitric acid, acetic acid, methanesulfonic acid, trifluoromethanesulfonic acid, paratoluenesulfonic acid, trifluoroacetic acid, phosphoric acid and the like.

The above-mentioned cohydrolysis reaction is not particularly limited, but is preferably carried out at 50 to 100 ° C. for 2 to 10 hours.

The above-mentioned cohydrolyzate may be used as it is for the water repellent treatment agent of the present invention, but if necessary, the above-mentioned hydrophilic solvent or aromatic hydrocarbons such as benzene, toluene and xylene, You may use it after diluting to a concentration of about 0.1 to 5% with an organic solvent such as esters such as ethyl acetate and isobutyl acetate. As a method of using it on the object to be treated, a durable water-repellent and antifouling surface can be obtained by applying it to the surface of the object to be treated by means such as dipping, spraying, brush coating, spinner, etc. and drying. In addition, although drying is sufficient at room temperature, heating at 40 to 200 ° C. for 5 to 60 minutes is more preferable from the viewpoint of durability.

[0027]

The water repellent agent of the present invention is excellent in the effect of imparting water repellency and the effect of improving the drop property of water drops, and can impart excellent water repellency and antifouling property to the surface of an object to be treated, and further, an organic solvent. It is soluble in water and can be used for surface treatment of materials with various inorganic surfaces. Specifically, it is an optical component such as window glass for buildings, railways, vehicles, aircrafts, mirrors, glass lenses, etc. It can be widely used for surface treatment of various glass appliances, pottery, tiles, plastic materials treated with inorganic antireflection coat, silicone hard coat and the like.

[0028]

EXAMPLES The present invention will be specifically described below with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples.

Example 1 A 1 liter glass reactor equipped with a thermometer, stirrer, and condenser was charged with the formula C ₈ F ₁₇ CH ₂ CH ₂ S.
10.0 g of a perfluoro group-containing organosilicon compound represented by i (OCH ₃ ) ₃ , 10.0 g of a hydrolyzable group-containing methylpolysiloxane compound represented by the following formula, 480.0 g of isopropanol as a hydrophilic solvent, and 0.1N hydrochloric acid 1.94 g of water was charged and cohydrolysis reaction was carried out at 80 ° C. for 5 hours to obtain a water repellent treatment agent solution. The system pH is 2.5.
Met.

[0030]

[Chemical 9]

[Examples 2 to 6 and Comparative Examples 1 and 2] Perfluoro group-containing organosilicon compound, hydrolyzable group-containing methylpolysiloxane compound, water, kind and addition amount of hydrophilic solvent, and cohydrolysis conditions are shown. Example 1 except that it was changed as shown in FIG.
A water repellent treatment agent solution was obtained in the same manner as in.

[Comparative Example 3] The same perfluoro group-containing organosilicon compound, hydrolyzable group-containing methylpolysiloxane compound, water and hydrophilic solvent as in Example 1 were used in the same amounts as in Example 1, but cohydrolysis was performed. Without reacting, these were simply mixed to obtain a water repellent treatment agent solution.

Next, the water repellent treatment solutions obtained in the above-mentioned Examples and Comparative Examples were respectively degreased and washed with acetone in advance, and then coated on a dried glass plate by dipping to a thickness of 4 μm, and then at 100 ° C. Was heat-treated for 10 minutes. For these surfaces, the contact angle of water, the drop angle of water droplets, and the antifouling property were measured by the following methods. The results are shown in Table 1. Dripped 5μl of water on a glass plate which was kept at a contact angle horizontal water contact angle measuring device [the Contact Angle Meter
CA-A (manufactured by Kyowa Scientific Co., Ltd.)] was used to measure the contact angle. Water drop angle static friction coefficient measuring machine (manufactured by Shinto Scientific Co., Ltd., HEIDON
-10 type), a glass plate was set horizontally, 100 μl of water was dripped, and then gradually inclined, and the angle at which the water started to drop was measured. A glass plate was set in an antifouling sunshine weather meter (manufactured by Suga Test Instruments Co., Ltd.) at an angle of 45 °, exposed for 100 hours, and then the appearance was observed.

From the results shown in Table 1, the water repellent treatment agent of the present invention (Example) is excellent in the water repellent effect and the drop property of water drops, and can impart excellent water repellency and antifouling property to the surface of the object to be treated. It was confirmed that it was possible.

[0035]

[Table 1]

[0036]

[Chemical 10]

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shoji Ichinohe 1 Hitomi, Otomi, Matsuida-cho, Usui-gun, Gunma 10 Shin-Etsu Chemical Co., Ltd. Silicone Electronic Materials Research Laboratory

Claims (1)

[Claims] 1. A perfluoroalkyl group-containing organosilicon compound represented by the following general formula (I):
A water repellent treatment agent comprising a cohydrolyzate of a hydrolyzable group-containing methylpolysiloxane compound represented by I) in water and a hydrophilic solvent. [Chemical 1] (However, in the formula, R ¹ is a monovalent hydrocarbon group having 1 to 4 carbon atoms, R ² is an alkoxy group or acyloxy group having 1 to 4 carbon atoms, and Q is a divalent organic group having 2 to 10 carbon atoms. Is a group, a is 0 or 1, and p is an integer of 1 to 12.)