JP2008274118A - Water repellency treating agent - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water repellency treating agent which can continue to exhibit water repellency over a long period of time while simultaneously imparting a high contact angle and a low falling angle. <P>SOLUTION: The water repellency treating agent comprises an alkylsilane represented by formula (1): R<SP>1</SP>SiR<SP>2</SP><SB>3-m</SB>R<SP>3</SP><SB>m</SB>, an organosiloxane having a kinematic viscosity at 25°C of 5-1,500 mm<SP>2</SP>/s, and a solvent at a compounding rate of the organosiloxane of 5-1,000 pts.wt. per 100 pts.wt. alkylsilane. On coating this water repellency treating agent on a base material, a high contact angle and a low falling angle can be simultaneously imparted to continue to exhibit such water repellency over a long period of time. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a water repellent treatment agent, and more particularly to a water repellent treatment agent used for water repellent treatment of a substrate.

  Conventionally, a water repellent treatment is performed on a windshield of an automobile using a water repellent treatment agent in order to impart water repellency.

  As such a water repellent treatment agent, for example, (A) an alkylalkoxysilane compound containing an alkyl group having 4 to 18 carbon atoms, (B) a silanol group-blocked polydiorganosiloxane oil, (C) an acid, and And (D) a surface treatment composition for vehicle glass containing a volatile solvent, wherein the weight ratio of (B) / (A) is 12 to 40 and the weight ratio of (C) / (A) is 2 to 5. Has been proposed (see, for example, Patent Document 1).

In addition, a water repellent composition containing (A) an alkylsilane compound, (B) acid, (C) dimethylpolysiloxane, and (D) a volatile solvent has been proposed (see, for example, Patent Document 2). .)
JP 2003-34553 A JP-A-10-121036

  However, in order to impart excellent water repellency to the windshield, the contact angle of water droplets on the windshield must be high, and furthermore, the angle at which the water droplets start moving relative to the windshield, that is, the falling angle must be low Is required.

  However, the surface treatment composition for vehicle glass described in Patent Document 1 and the water-repellent treatment composition described in Patent Document 2 cannot impart a sufficiently high contact angle to the windshield, The falling angle cannot be reduced, and furthermore, excellent water repellency cannot be imparted over a long period of time.

  An object of the present invention is to provide a water-repellent treatment agent capable of continuing to exhibit these water repellency over a long period of time while simultaneously imparting a high contact angle and a low sliding angle.

In order to solve the above object, the water-repellent treatment agent of the present invention has an alkylsilane represented by the following general formula (1), a hydroxyl group or an alkoxy group at both ends of the molecule, and a kinematic viscosity at 25 ° C. 5 to 1500 mm ² / s of organosiloxane and a solvent are contained, and the blending ratio of the organosiloxane is 5 to 1000 parts by weight with respect to 100 parts by weight of the alkylsilane.

R ¹ SiR ² _3-m R ³ _m (1)
(In the formula, R ¹ represents a linear or branched alkyl group having 6 to 18 carbon atoms, R ² represents methoxy, ethoxy or chloro, R ³ represents methyl or ethyl, and m represents 0 to 2) Indicates an integer.)
In the water repellent agent of the present invention, it is preferable that R ² in the general formula (1) is methoxy or ethoxy and further contains an acid.

In the water repellent agent of the present invention, R ¹ in the general formula (1) is preferably an alkyl group having 8 to 12 carbon atoms.

In the water-repellent treatment agent of the present invention, it is preferable that the organosiloxane has a kinematic viscosity of 5 to 700 mm ² / s.

  In the water-repellent treatment agent of the present invention, it is preferable that a blending ratio of the organosiloxane is 5 to 300 parts by weight with respect to 100 parts by weight of the alkylsilane.

  The water-repellent treatment agent of the present invention contains a specific alkylsilane, an organosiloxane having a hydroxyl group or an alkoxy group at both ends of the molecule, and a solvent, and the mixing ratio of the organosiloxane is 100 parts by weight of the alkylsilane. On the other hand, it is 5 to 1000 parts by weight. Therefore, if the water-repellent treatment agent of the present invention is applied to a substrate, a high contact angle and a low falling angle can be simultaneously imparted, and these water repellency can be continuously exhibited over a long period of time.

  The water repellent treatment agent of the present invention contains an alkyl silane, an organosiloxane, and a solvent.

  The alkylsilane is a long-chain alkyl tri-, di- or monoalkoxysilane, or a long-chain alkyl tri-, di- or monochlorosilane, and more specifically is represented by the following general formula (1).

R ¹ SiR ² _3-m R ³ _m (1)
(In the formula, R ¹ represents a linear or branched alkyl group having 6 to 18 carbon atoms, R ² represents methoxy, ethoxy or chloro, R ³ represents methyl or ethyl, and m represents 0 to 2) Indicates an integer.)
In the general formula (1), as R ¹ , for example, hexyl, heptyl, octyl, 2-ethylhexyl, isooctyl, nonyl, isononyl, decyl, isodecyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl And a linear or branched alkyl group having 6 to 18 carbon atoms such as octadecyl. If the carbon number of the alkyl group is in the range of 6 to 18, durability can be improved while preventing an increase in the falling angle.

Preferably, R ¹ includes an alkyl group having 8 to 12 carbon atoms such as octyl, 2-ethylhexyl, isooctyl, nonyl, isononyl, decyl, isodecyl, undecyl, dodecyl and the like. If the carbon number of the alkyl group is in the range of 8 to 12, durability may be further improved while reliably preventing an increase in the falling angle.

In the general formula (1), R ² is preferably methoxy or ethoxy.

In the general formula (1), R ³ is preferably methyl.

  In the general formula (1), m is preferably 0 or 1, and more preferably 0.

  More specifically, examples of the alkylsilane represented by the general formula (1) include hexyltrimethoxysilane, octyltrimethoxysilane, decyltrimethoxysilane, dodecyltrimethoxysilane, tetradecyltrimethoxysilane, and hexadecyltrisilane. Long-chain alkyltrimethoxysilane such as methoxysilane, octadecyltrimethoxysilane, such as hexyltriethoxysilane, octyltriethoxysilane, decyltriethoxysilane, dodecyltriethoxysilane, tetradecyltriethoxysilane, hexadecyltriethoxysilane, Long-chain alkyltriethoxysilanes such as octadecyltriethoxysilane, such as hexyltrichlorosilane, octyltrichlorosilane, decyltrichlorosilane, dodecyltrichlorosilane Emissions, tetradecyl trichlorosilane, hexadecyl trichlorosilane, and long-chain alkyl trichlorosilane such as octadecyl trichlorosilane and the like.

  These alkylsilanes can be used alone or in combination of two or more.

  The organosiloxane is a both-end type modified silicone oil (both ends-type reactive silicone oil) having hydroxyl groups or alkoxy groups at both ends of the molecule, and is represented by, for example, the following general formula (2).

(In the general formula (2), R ⁴ represents a substituted or unsubstituted, non-reactive monovalent hydrocarbon group, R ⁵ represents a hydroxyl group or an alkoxy group. And n represents an integer of 9 to 450.)
In the general formula (2), as R ⁴ , for example, an unsubstituted alkyl group such as methyl, ethyl, propyl, butyl, hexyl, a substituted alkyl group such as 3,3,3-trifluoropropyl, for example, And an unsubstituted aryl group such as phenyl. Preferably, R ⁴ includes methyl.

In the general formula (2), R ⁵ is preferably a hydroxyl group.

  In the general formula (2), p and q may be the same or different from each other, and each represents, for example, an integer of 1 to 3, preferably 3.

  In General formula (2), n is a polymerization degree, for example, 9-450, Preferably, it is 9-300, More preferably, it is 9-40. When n exceeds the above-described range, the falling angle may increase and the durability may decrease. On the other hand, if n is less than the above-mentioned range, a good falling angle may not be provided.

The organosiloxane may be referred to as a both-end hydroxyl group-containing dimethylpolysiloxane (both end-type silanol-modified dimethylpolysiloxane) when R ⁵ is a hydroxyl group.

Moreover, kinematic viscosity at 25 ° C. The organosiloxane is 5~1500mm ² / s, preferably, 5~700mm ² / s, and more preferably from 5 to 35 mm ² / s.

  When the kinematic viscosity exceeds the above range, a high contact angle and a low sliding angle cannot be imparted, and the durability is further deteriorated. On the other hand, when the kinematic viscosity is less than the above-described range, it is not possible to provide a favorable falling angle.

  These organopolysiloxanes can be used alone or in combination of two or more.

  The compounding ratio of the organosiloxane is 5 to 1000 parts by weight, preferably 5 to 300 parts by weight with respect to 100 parts by weight of the alkylsilane.

  When the compounding ratio of the organosiloxane exceeds the above range, a high contact angle and a low sliding angle cannot be provided. Furthermore, durability, more specifically, when the substrate is a windshield or rear glass of an automobile, wiping resistance (friction resistance) cannot be improved.

  The solvent is not particularly limited as long as alkylsilane and organosiloxane can be dispersed or dissolved. For example, the solvent is a volatile solvent. Examples of such a solvent include methanol, ethanol, propanol, isopropanol (isopropyl alcohol), butanol. , Isobutanol, s-butanol, t-butanol, etc., petroleum solvents such as mineral spirits, for example, n-hexane, n-heptane, n-octane, isooctane, nonane, decane, undecane, dodecane Aliphatic hydrocarbon solvents such as benzene, toluene, xylene, and the like, and silicone solvents such as volatile dimethylpolysiloxane. Preferably, an alcohol solvent and an aliphatic hydrocarbon solvent are used.

  These solvents can be used alone or in combination of two or more.

  The mixing ratio of the solvent is, for example, 500 to 25000 parts by weight, preferably 5000 to 15000 parts by weight with respect to 100 parts by weight of the alkylsilane. If the blending ratio of the solvent exceeds the above range, good water repellency may not be imparted. If the blending ratio of the solvent is less than the above range, workability may be deteriorated.

  The water repellent agent of the present invention can further contain an acid.

The acid is, for example, when R ² in the above general formula (1) is methoxy or ethoxy, that is, the alkylsilane is a long chain alkyl (mono, di or tri) methoxysilane or a long chain alkyl (mono, di or In the case of tri) ethoxysilane, it is added to the water repellent agent.

  Examples of such acids include inorganic acids such as hydrochloric acid, sulfuric acid, and nitric acid, and organic acids such as acetic acid and formic acid.

  These acids can be used alone or in combination of two or more.

  The mixing ratio of the acid is, for example, 1 to 40 parts by weight, preferably 1 to 20 parts by weight with respect to 100 parts by weight of the alkylsilane. If the above range is exceeded, workability may be reduced or cost may be increased. If it is less than the above-mentioned range, the effect of acid blending may not be obtained.

  When such an acid is contained, the acid functions as a catalyst for improving the reactivity of the alkylsilane. More specifically, the reaction of methoxy or ethoxy of the alkylsilane with the hydroxyl group or alkoxy group of the organosiloxane. It is possible to improve the durability and to impart a high contact angle and a low sliding angle to improve durability.

  And in order to obtain the water-repellent treatment agent of this invention, alkylsilane, organosiloxane, a solvent, and the acid mix | blended as needed are mix | blended suitably with the above-mentioned mixture ratio.

  In addition, the water repellent treatment agent of the present invention is usually added to the water repellent treatment agent within a range not inhibiting the effects of the present invention, for example, a viscosity modifier, an antioxidant, an ultraviolet absorber, a rust preventive agent, Additives such as fragrances and colorants can be appropriately blended.

  And the water repellent agent of this invention obtained in this way is used for the water-repellent treatment of a base material, for example.

  The substrate is not particularly limited as long as it is required to have water repellency when wet, such as a window glass of a vehicle such as an automobile, a mirror, a painted surface, such as a building wall, a window, a roof, For example, a side mirror of a car, a mirror such as a curve mirror on the road, and the like can be given. Preferably, a window glass of an automobile, more specifically, a windshield, a rear glass, and the like that require wiping resistance that does not deteriorate water repellency even by friction with a wiper.

  In order to perform the water repellent treatment on the substrate, the water repellent treatment agent of the present invention is applied to the substrate.

  Application to the base material is not particularly limited, and for example, a known method is appropriately used such as including the water-repellent treatment agent of the present invention in an absorbent paper such as tissue paper and rubbing the base material with the absorbent paper. . In addition, the application | coating method can apply | coat directly, for example with cloth, a brush, a sponge, etc., or can also spray it with a spray.

  In addition, after application, for example, it may be dried at room temperature, and if necessary, excess water repellent agent may be wiped off (or wiped up).

  The water-repellent treatment agent of the present invention contains a specific alkylsilane, an organosiloxane having a hydroxyl group or an alkoxy group at both ends of the molecule, and a solvent. 5 to 1000 parts by weight with respect to parts. Therefore, when the water repellent treatment agent of the present invention is applied to a substrate, more specifically, to a window glass of an automobile or the like, a high contact angle of water and a low falling angle can be expressed with respect to the window glass.

  Furthermore, it is possible to continue to exhibit water repellency such as excellent contact angle and falling angle of water droplets on the window glass over a long period of time. In particular, excellent wiping resistance can be imparted over a long period to the windshield or rear glass.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. However, the present invention is not limited to these examples and comparative examples.

Example 1
・ Decyltrimethoxysilane 100 parts by weight ・ Both-terminal hydroxyl group-containing dimethylpolysiloxane 100 parts by weight (viscosity 30 mm ² / s (25 ° C.))
-Hydrochloric acid 30 weight part-Isopropyl alcohol 9000 weight part In the said composition, the water-repellent processing agent was obtained by mix | blending and mixing each component with isopropyl alcohol.

Example 2
As in Example 1, except that 100 parts by weight of decyltrimethoxysilane was used, 100 parts by weight of decyltrichlorosilane was used, 9000 parts by weight of isooctane was used instead of 9000 parts by weight of isopropyl alcohol, and hydrochloric acid was not used. The water repellent was obtained by blending.

Example 3
A water repellent was obtained in the same manner as in Example 1 except that 100 parts by weight of hexyltrimethoxysilane was used instead of 100 parts by weight of decyltrimethoxysilane.

Example 4
A water repellent was obtained by blending in the same manner as in Example 1 except that 100 parts by weight of octadecyltrimethoxysilane was used instead of 100 parts by weight of decyltrimethoxysilane.

Example 5
Instead of 100 parts by weight of both-end-type hydroxyl group-containing dimethylpolysiloxane (viscosity 30 mm ² / s (25 ° C.)), 100 parts by weight of both-end-type hydroxyl group-containing dimethylpolysiloxane (viscosity 700 mm ² / s (25 ° C.)) A water repellent was obtained by blending in the same manner as in Example 1 except that was used.

Example 6
Instead of 100 parts by weight of both-end-type hydroxyl group-containing dimethylpolysiloxane (viscosity 30 mm ² / s (25 ° C.)), 100 parts by weight of both-end-type hydroxyl group-containing dimethylpolysiloxane (viscosity 1500 mm ² / s (25 ° C.)) A water repellent was obtained by blending in the same manner as in Example 1 except that was used.

Example 7
Instead of 100 parts by weight of decyltrimethoxysilane, 100 parts by weight of hexyltrimethoxysilane was used, and instead of both ends-type hydroxyl group-containing dimethylpolysiloxane (viscosity 30 mm ² / s (25 ° C.)), both ends-type hydroxyl groups A water repellent was obtained in the same manner as in Example 1 except that the dimethylpolysiloxane containing (viscosity 1500 mm ² / s (25 ° C.)) was used.

Example 8
Dual end-hydroxyl group-containing dimethylpolysiloxane (viscosity of ^{30mm 2 / s (25 ℃)} ) in place of 100 parts by weight, dual end-hydroxyl group-containing dimethylpolysiloxane (viscosity of ^{30mm 2 / s (25 ℃)} ) 300 parts by weight A water repellent was obtained by blending in the same manner as in Example 1 except that was used.

Example 9
Dual end-hydroxyl group-containing dimethylpolysiloxane (viscosity of ^{30mm 2 / s (25 ℃)} ) in place of 100 parts by weight, dual end-hydroxyl group-containing dimethylpolysiloxane (viscosity of ^{30mm 2 / s (25 ℃)} ) 1000 parts by weight Was used in the same manner as in Example 1 except that 8500 parts by weight of isopropyl alcohol was used instead of 9000 parts by weight of isopropyl alcohol to obtain a water repellent treatment agent.

Comparative Example 1
Both end-type hydroxyl group-containing dimethylpolysiloxane (viscosity 30 mm ² / s (25 ° C.)) instead of 100 parts by weight Both-end hydroxyl group-containing dimethylpolysiloxane (viscosity 30 mm ² / s (25 ° C.)) 1500 parts by weight Was used in the same manner as in Example 1 except that 8000 parts by weight of isopropyl alcohol was used instead of 9000 parts by weight of isopropyl alcohol to obtain a water repellent treatment agent.

Comparative Example 2
Implemented except that dimethylsiloxane (non-reactive silicone oil, viscosity 30 mm ² / s (25 ° C.)) was used in place of the both-end hydroxyl group-containing dimethylpolysiloxane (viscosity 30 mm ² / s (25 ° C.)) In the same manner as in Example 1, a water repellent treatment agent was obtained.

Comparative Example 3
Instead of 100 parts by weight of both-end type hydroxyl group-containing dimethylpolysiloxane (viscosity 30 mm ² / s (25 ° C.)), 100 parts by weight of both-end type hydroxyl group-containing dimethylpolysiloxane (viscosity 5000 mm ² / s (25 ° C.)) A water repellent was obtained by blending in the same manner as in Example 1 except that was used.

(Evaluation)
1. Water repellent treatment The water repellent treatment agent of each example and each comparative example is included in tissue paper, and the tissue paper is rubbed with a glass plate (size 150 mm × 70 mm, thickness 2.0 mm, manufactured by Dazai Equipment Co., Ltd.). After applying the water repellent treatment agent, the glass plate was dried at room temperature to give the glass plate a water repellent treatment.
2. Evaluation The glass plate treated with water repellency was evaluated by the following measurements. The results are shown in Table 1.
1) Contact angle After setting a glass plate to the contact angle meter (model number FTA125, FTA company make), the contact angle of 4 microliters of water droplets was measured.
2) Falling angle After setting the glass plate on a contact angle meter (model number FTA125, manufactured by FTA), the angle at which 30 μl of water droplets started to move, that is, the falling angle was measured.
3) Abrasion resistance 4 ml of 1% cerium oxide aqueous dispersion was included in a sponge, and this was attached to a washerability tester (model number 552, manufactured by Yasuda Seiki Seisakusho). Thereafter, the glass plate was set in this testing machine, and the glass plate was rubbed 400 times with a sponge while applying a load of 12.5 g / cm ² . Then, after setting the glass plate after rubbing on a contact angle meter (model number FTA125, manufactured by FTA), the wear angle was evaluated by measuring the contact angle of 4 μl of water droplets.

Claims (5)

An alkylsilane represented by the following general formula (1), an organosiloxane having a hydroxyl group or an alkoxy group at both ends of the molecule, a kinematic viscosity at 25 ° C. of 5 to 1500 mm ² / s, and a solvent,
The water-repellent treatment agent, wherein a blending ratio of the organosiloxane is 5 to 1000 parts by weight with respect to 100 parts by weight of the alkylsilane.
R ¹ SiR ² _3-m R ³ _m (1)
(Wherein R ¹ represents a linear or branched alkyl group having 6 to 18 carbon atoms, R ² represents methoxy, ethoxy or chloro, R ³ represents methyl or ethyl, and m represents 0 to 2) Indicates an integer.) R ² in the general formula (1) is methoxy or ethoxy,
The water repellent treatment agent according to claim 1, further comprising an acid. The water repellent agent according to claim 1 or 2, wherein R ¹ in the general formula (1) is an alkyl group having 8 to 12 carbon atoms. The water repellent treatment agent according to claim 1, wherein the organosiloxane has a kinematic viscosity at 25 ° C. of 5 to 700 mm ² / s.   The water-repellent treatment agent, wherein a blending ratio of the organosiloxane is 5 to 300 parts by weight with respect to 100 parts by weight of the alkylsilane.