JP2009137775A - Water repellant for glass - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water repellant for glass which exhibits initial water repellency immediately after application and retains its water repellency even after rainfall and the like. <P>SOLUTION: The water repellant for glass comprises an amino-modified polysiloxane and a polysiloxane having an OR group at a terminal of a main chain. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention is a water-repellent treatment agent that imparts water repellency to automobile window glass, architectural window glass, and other glass, and in particular, does not require drying / coating after coating, and is applied to the glass surface by spraying or the like. The present invention relates to a simple water-repellent treatment agent that is immediately effective.

Conventionally, amino-modified polysiloxane (so-called aminosilicone) has been often used for the purpose of imparting water repellency to glass (Patent Document 1, etc.).

This is because, unlike polysiloxane which is not amino-modified, this aminosilicone can be used even if moisture remains on the glass surface, and has an advantage that it is easy and safe to handle.

However, the water-repellent treatment agent containing aminosilicone is excellent in water repellency immediately after application, but has poor sustainability. For example, when it is rained after application, it is several tens of seconds. There was a tendency to lose the effect.

On the other hand, in order to improve water repellency in a defrosting and deicing agent, a technique of using other silicones in combination with aminosilicone has been proposed (Patent Document 2).

This defrosting deicing agent is intended to provide water repellency with water-insoluble silicone so that the melted ice does not refreeze at the same time as the defrosting, It is intended to improve the “initial water repellency” after application by hydrophobizing the water after deicing with water-insoluble silicone and preventing adhesion to the glass surface. It does not solve the above-mentioned problem that the water-repellent effect does not last.

JP 7-41336 A JP 2004-59846 A

Accordingly, an object of the present invention is to provide a water repellent for glass that maintains water repellency not only after initial application but also after rain.

The above-described object is achieved by the following first to sixth inventions.

<First invention>
A water repellent comprising an amino-modified polysiloxane, further comprising a polysiloxane having an OR group at the end of the main chain.
(R is hydrogen or a C1-C6 hydrocarbon.)

<Second invention>
Furthermore, the water repellent for glass according to the first invention, further comprising an acid.

<Third invention>
The water-repellent agent for glass according to the first invention or the second invention, wherein the amino-modified polysiloxane has a kinematic viscosity at 25 ° C. of 10 to 5000 cst.

<Fourth Invention>
The water-repellent agent for glass according to any one of the first to third inventions, wherein the amino-modified polysiloxane has an amino equivalent of 300 to 10,000.

<Fifth invention>
The water repellent for glass according to any one of the first to fourth inventions, characterized in that the polysiloxane having an OR group at the end of the main chain has a kinematic viscosity at 25 ° C of 5 to 3000 cst. .

<Sixth invention>
The content of the amino-modified polysiloxane is 0.01 to 10.0% by mass, and the content of the polysiloxane having an OR group at the end of the main chain is 0.01 to 10.0% by mass. The water repellent for glass according to any one of the first invention to the fifth invention.

The water repellent for glass of the present invention is a water repellent for glass that maintains water repellency not only after initial application but also after rain.

[Definition of water repellent for glass]
The water repellent for glass of the present invention imparts water repellency to the glass surface, including not only the product name of water repellent, but also the names of window washer, glass cleaner, defrosting agent, deicing agent and other products. It is intended to include all compositions that have at least one objective.

[Amino-modified polysiloxane]
The amino-modified polysiloxane used in the present invention is a polysiloxane having an amino group at the side chain or terminal.

Any amino-modified polysiloxane may be used as long as it is a known one used for water repellents, and various amino groups can be used.

The amino-modified polysiloxane is preferably an alkyl group having 1 to 3 carbon atoms or an alkoxy group having 1 to 3 carbon atoms, and particularly preferably an alkoxy group.
This is because the alkoxy group undergoes hydrolysis in the presence of water, causes a crosslinking reaction, and increases in the degree of polymerization, so that it becomes difficult to dissolve in water and to be washed away by rainfall. This is because it reacts with the SiOH group on the glass surface and chemically adsorbs to the glass surface, so that it is resistant to rainfall and wiping, and water repellency persistence increases.

Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, and the like. Among them, a methyl group is preferable.
Examples of the alkoxy group include a methoxy group, an ethoxy group, and a propoxy group.

The ends of the amino-modified polysiloxane used in the present invention may be the same or different.

Specific examples of the amino-modified polysiloxane include, but are not limited to, those represented by the following formula [1] or [2], and two or more kinds of amino-modified polysiloxanes: A combination of siloxanes can also be used.

In the above formula [1], X and Y are preferably the above-mentioned alkyl group having 1 to 3 carbon atoms or an alkoxy group having 1 to 3 carbon atoms, and among them, a methyl group or an alkoxy group. Wherein l and m are integers of 1 or more, A ¹ is preferably —R ₁ —NH ₂ or —R ₂ NHR ₃ NH ₂ , and R ₁ , R ₂ , and R ₃ are each represented by Independently representing a divalent hydrocarbon, the divalent hydrocarbon is, for example, generally a hydrocarbon group having 1 to 5 carbon atoms, specifically, an ethylene group, a propylene group, etc. It is preferable that the amino-modified polysiloxane has a kinematic viscosity at 25 ° C. and an amino equivalent that are suitable values described below.

Specifically, the amino-modified polysiloxane represented by the above formula [1] can be obtained from the market as the following.

In the above formula, A ² and A ³ each independently represent a methyl group, an alkoxy group (for example, a methoxy group, an ethoxy group, a propoxy group, etc.), —R ₄ —NH ₂ , or —R ₅ NHR ₆ NH ₂ ; At least one is —R ₄ —NH ₂ or —R ₅ NHR ₆ NH ₂ . R ₄ , R ₅ and R ₆ each independently represents a divalent hydrocarbon group, and n represents an integer of 1 or more.

In the general formula [2], the divalent hydrocarbon group represented by R ₄ , R ₅ and R ₆ is not particularly limited, but a hydrocarbon group having 1 to 5 carbon atoms is generally used. Specifically, an ethylene group, a propylene group, etc. are mentioned. In the above general formula [2], n is preferably an integer that satisfies the kinematic viscosity and equivalent described later.

Specifically, the amino-modified polysiloxane represented by the above formula [2] can be obtained from the market as the following.

The amino-modified polysiloxane used in the present invention preferably has a kinematic viscosity at 25 ° C. of 10 to 5000 cst, more preferably 20 to 2000 cst.

This is because when it is 10 cst or more, it is particularly excellent in the effect of imparting water repellency to the glass surface, and when it is 5000 cst or less, it is particularly difficult to form an oil film and has the advantage of excellent water repellency.

The amino-modified polysiloxane used in the present invention preferably has an amino equivalent of 300 to 10,000, more preferably 500 to 5,000.

When it is 300 or more, it is particularly excellent in the effect of imparting water repellency, and when it is 10,000 or less, it is particularly excellent in adsorptivity to the glass surface, and it is excellent in water solubility and uniform dispersibility in the water repellent, and particularly in oil films. This is because it has the advantage that it is difficult to be formed and has excellent water repellency.

The content of the amino-modified polysiloxane in the water repellent for glass of the present invention is preferably 0.01 to 10% by mass, and more preferably 0.5 to 5% by mass.

Since it is 0.01% by mass or more, the falling angle of water droplets adhering to the glass is particularly low, the water repellency is excellent, and 10% by mass or less is particularly difficult to form an oil film and has the advantage of excellent water repellency. is there.

[Polysiloxane having an OR group at the end of the main chain]
The polysiloxane having an OR group at the end of the main chain used in the present invention is one having an OR group at one end or both ends of the main chain. It is preferable in terms of maintenance.

R in the OR group is hydrogen or a hydrocarbon having 1 to 6 carbon atoms, preferably hydrogen or a hydrocarbon having 1 to 3 carbon atoms.

Examples of the hydrocarbon include saturated (alkyl) and unsaturated (alkenyl, alkynyl), and also include a straight chain and a branched chain.

Specific examples include methyl, ethyl, vinyl (ethenyl), acetyl, propyl, isopropyl, propadienyl, propynyl, butyl, isobutyl, t-butyl, pentyl, hexyl and the like, with isopropyl being preferred.

This hydrocarbon group may be introduced into the polysiloxane from the beginning as OR. However, by using OR as a hydroxyl group and using alcohols as a raw material for the glass water repellent, the composition of the water repellent is used. Thus, OH can be modified to OR by a dehydration condensation reaction so that it can be contained in the water repellent.
In that case, isopropanol or the like is often used as the alcohol to be used together, and therefore the R group is preferably an isopropyl group.

The kinematic viscosity at 25 ° C. of the polysiloxane having an OR group at the end of the main chain is preferably 5 to 3000 cst, and more preferably 10 to 1000 cst.

This is because, when it is 5 cst or more, the falling angle of water droplets adhering to the glass is particularly low and the water repellency is excellent, and when it is 3000 cst or less, it is particularly difficult to form an oil film and the water repellency is excellent.

Such polysiloxanes having an OR group at the end of the main chain can be obtained from the market as the following, but are not limited thereto, and are also not limited to the end of the main chain. Two or more kinds of polysiloxanes having OR groups can be used in combination.

The content of the polysiloxane having an OR group at the end of the main chain in the water repellent for glass of the present invention is preferably 0.01 to 10% by mass, more preferably 0.1 to 5.0% by mass. It is.
This is because it is particularly excellent in water repellency at 0.01% by mass or more, and has an advantage that it is difficult to form an oil film and is excellent in water repellency at 10% by mass or less.

In the water repellent for glass of the present invention, the content ratio of the amino-modified polysiloxane and the polysiloxane having an OR group at the end of the main chain is preferably 0.01: 10 to 10: 0.01, particularly Preferably, it is 0.02: 5-5: 0.1.

When the ratio of the polysiloxane having an OR group at the end of the main chain is less than 0.01: 10, the water repellent effect is particularly excellent. It is because it is excellent in.

It is preferable that the water repellent for glass of the present invention further contains an acid.

Examples of the acid include organic acids, inorganic acids, and mixtures thereof.
Examples of organic acids include formic acid, acetic acid, lactic acid, mono-, di- and tri-chloroacetic acid, mono-, di- and tri-fluoroacetic acid, p-toluenesulfonic acid, benzenesulfonic acid, ethylsulfonic acid, and methylsulfone. Acid, ethylenedisulfonic acid, dodecylsulfonic acid, trifluoromethylsulfonic acid, perfluoroalkylcarboxylic acids, perfluoroalkylsulfonic acids, maleic acid, picric acid, trihydroxybenzoic acid, trinitrophenol, sulfamic acid, fluorosilicic acid, Examples include chlorosulfonic acid, fluorosulfonic acid, and mixtures thereof.

Inorganic acids include sulfuric acid, sulfurous acid, fuming sulfuric acid (oleum), hydrofluoric acid, hydrochloric acid, hydrobromic acid, phosphoric acid, phosphorous acid, pyrophosphoric acid, nitric acid, hydrogen sulfide, iodic acid, and mixtures thereof. Is mentioned.

In the present invention, even if it is not a strong acid such as sulfuric acid or sulfonic acid, a carboxylic acid is sufficient, so that a water repellent with higher safety can be obtained. Examples of the carboxylic acid include formic acid, acetic acid, lactic acid, tri-fluoroacetic acid, perfluoroalkylcarboxylic acids, maleic acid, picric acid, and trihydroxybenzoic acid, but have high water repellency. Formic acid, acetic acid and lactic acid are preferred, and formic acid is more preferred.

In addition, the said acid can use the thing of the form of aqueous solution or an alcohol solution, for example, things, such as 10-90% aqueous solution, can be used.

The content of the acid in the water repellent for glass of the present invention is preferably 0.0001 to 0.5% by mass, for example, as the amount of the “acid” itself when the total water repellent is 100. More preferably, it is 0.0002-0.1 mass%.

When the amount of the acid is 0.0001% by mass or more, it reacts with the amino-modified polysiloxane and is excellent in the effect of increasing its water solubility, and when the terminal of the amino-modified polysiloxane is an alkoxy group, This is because it is excellent in the catalytic action of the crosslinking reaction. Moreover, it is because it has the advantage that it is excellent in the initial stage water repellency immediately after application | coating of the water repellent to a glass surface, and it is excellent also in the durability of water repellency, when the amount of acid is 0.1 mass% or less.

In addition to the above, the water repellent for glass of the present invention may contain various solvents such as water and alcohol, and other components generally used in glass repellents, as long as the object of the present invention is not impaired. it can.
For example, various surfactants such as anionic surfactants, amphoteric surfactants, nonionic surfactants, colorants such as stickers, oils, dyes, resins, pigments, fragrances, preservatives, antibacterial agents, Components such as an antioxidant, a chelating agent, a pearling agent, a neutralizing agent, and a pH adjusting agent can be appropriately blended.

Alcohol solvents include methyl alcohol, ethyl alcohol, vinyl (ethenyl) alcohol, acetyl alcohol, propyl alcohol, isopropyl alcohol, propadienyl alcohol, propynyl alcohol, butyl alcohol, isobutyl alcohol, t-butyl alcohol, pentyl alcohol, hexyl alcohol Although isopropyl alcohol etc. are preferable.

EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated, this invention is not limited to these.

Prior to the examples, test methods for confirming the performance of the present invention will be described below.

[Testing method for confirming water repellency and water repellency]
After spraying each water repellent of Examples and Comparative Examples with a pump-type hand spray on a glass plate that has been made wet with water by removing oil and dirt on the surface with Compound 99 for glass manufactured by Soft99 The glass surface was rubbed 5 times in a fixed direction with a draining wiper to completely remove the water on the surface, and this was used as a test plate.
After measuring the contact angle and the falling angle (initial water repellency) of this test plate, it was washed with running water for 1 minute, and the contact angle and the falling angle were measured again.

The contact angle and sliding angle were measured using a dynamic contact angle meter FTA125 manufactured by FTA.
The volume of water droplets to be sprayed to measure the contact angle and the drop angle was 4 μl and 30 μl, respectively.

The larger the contact angle and the smaller the falling angle, the better the water repellency.
Moreover, it shows that it is excellent in water-repellent sustainability, so that the maintenance property of these angles is excellent.

[Practical test method for water repellency]
The car windshield (2007 Toyota Motor Corolla Filter, tilt angle of about 40 degrees) was polished with Soft 99 glass compound Z to remove oil and dirt on the surface, making it wet. .
After spraying the water repellents of Examples and Comparative Examples over the entire glass with a hand sprayer, the wiper was operated 45 times (for 1 minute) with LOW while applying water, and then traveled in the rain. .

(Evaluation criteria)
The above practical test results were evaluated according to the following criteria.

When the raindrops on the glass surface move toward the roof at less than 60 km / h and a good field of view is obtained without a wiper: ○
If there is no wiper and some water droplets remain, but the vehicle was able to run sufficiently: △
If raindrops remain on the glass surface and good visibility cannot be obtained without a wiper, it is difficult to run: ×

[Examples 1 to 4, Comparative Example 1]
Water repellents for glass of Examples 1 to 4 and Comparative Example 1 were produced with the compositions shown in Table 4 below.

[Test Example 1]
According to the above water repellency confirmation test method, the initial water repellency (contact angle and sliding angle) of Examples and Comparative Examples was confirmed, and the results are shown in Table 5, FIG. 1 and FIG.

[Test Example 2]
According to the water repellency persistence confirmation test method described above, the repellency of the water repellent performance (maintenance of the contact angle and the falling angle) of Examples and Comparative Examples was confirmed, and the results are shown in Table 5, FIG. 1 and FIG. Show.

[Test Example 3]
Table 5 shows the results of carrying out a running test using an automobile in accordance with the above-described practical test method for water repellency and evaluating it based on the above evaluation criteria.

As can be seen from Table 5, FIG. 1, and FIG. It was very good for both sustainability.
In particular, Example 1 used in combination with an acid was superior to Example 2.
In Example 3, the contact angle was almost the same as that of Comparative Example 1, but as shown in Test Example 2, the sliding angle was much better than Comparative Example 1.
Example 4 was superior to Comparative Example 1 in both contact angle and sliding angle, although not as much as in Examples 1 and 2.

As can be seen from Table 5, as a result of the running test according to Test Example 3, particularly good results were obtained in Examples 1 and 2.
In addition, Examples 3 and 4 were not as good as Examples 1 and 2, but good results were obtained.
On the other hand, in Comparative Example 1, traveling was difficult.

As can be seen from the results of each of the above test examples and the like, the water repellent for glass surface of the present invention of the example was superior in water repellency and its durability compared to the comparative example. In particular, Comparative Example 1 was superior in water repellency after wetting with water as compared to the water repellency performance rapidly decreasing (increasing the falling angle) after wetting with water.
The effect of maintaining the falling angle is more important than the large contact angle in practical use, and this is supported by the results of the running test.

In addition, when the amino-modified polysiloxane used in the above-mentioned examples is changed to the other ones shown in Tables 1 and 2, or in the above-mentioned examples, the poly having an OR group at the end of the main chain is used. Even when the siloxane was changed to that shown in Table 3, good results were obtained as compared with the comparative example.
Among them, as amino-modified polysiloxane, L655, WR1300, KF-393, KF-880, KF-8004, X-21-161-A, KF-8008, KF-8012 having a kinematic viscosity of 20 to 2000 cst are used. Or when L655, WR1300, KF-861, KF-880, KF-8004, X-21-161-A, KF-8012 having an amino equivalent of 500 to 5000 were used. It was.

The water repellent for glass of the present invention is a water repellent for glass that maintains water repellency not only after initial application but also after rain.

It is the figure which graphed the contact angle before and behind water washing of Table 5. It is the figure which graphed the fall angle before and behind water washing of Table 5.

Claims (6)

A water repellent comprising an amino-modified polysiloxane, further comprising a polysiloxane having an OR group at the end of the main chain.
(R is hydrogen or a C1-C6 hydrocarbon.) The water repellent for glass according to claim 1, further comprising an acid. The water repellent for glass according to claim 1, wherein the amino-modified polysiloxane has a kinematic viscosity at 25 ° C. of 10 to 5000 cst. The water-repellent agent for glass according to any one of claims 1 to 3, wherein the amino equivalent of the amino-modified polysiloxane is 300 to 10,000. 5. The water repellent for glass according to claim 1, wherein the polysiloxane having an OR group at the end of the main chain has a kinematic viscosity at 25 ° C. of 5 to 3000 cst. The content of the amino-modified polysiloxane is 0.01 to 10.0% by mass, and the content of the polysiloxane having an OR group at the end of the main chain is 0.01 to 10.0% by mass. The water repellent for glass according to any one of claims 1 to 5.