JPH1036820A - Water repellent and method for water repellent finishing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a water repellent which makes it possible to easily remove an unreacted silane compound after being applied and dried by wiping with water without using an alcohol, by using a specified compound as a silane compound in a water repellent comprising a solution or dispersion of a silane compound in a solvent. SOLUTION: The silane compound used in the water repellent comprises a compound represented by the formula, wherein part or all of the terminal M1 , M2 and M3 are hydroxyl groups, preferably heptadecafluorodecyltrimethoxysilane having part or all of the methoxy groups substituted by hydroxyl groups. This compound serves to form a durable water- repellent film since its hydroxyl groups readily react and combine with the hydroxyl groups on the surface of a base material, such as glass. Preferably, a terminator is incorporated into this water repellent to improve the shelf stability.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water repellent and a water repellent applied to, for example, window glass and side mirror glass of automobiles. More specifically, the present invention relates to a water-repellent treatment agent and a water-repellent treatment method capable of removing unreacted silane compounds by wiping after coating and drying.

[0002]

2. Description of the Related Art
For example, as a water repellent treatment agent applied to a window glass or a side mirror glass of an automobile, Japanese Patent Application Laid-Open No. Sho 50-1 is disclosed.
As disclosed in Japanese Patent No. 5473, there is one in which polydimethylsiloxane, polymethylphenylsiloxane, or the like is dispersed in an alcohol solution.

[0003] However, in this water repellent,
It is only spread thinly on the surface of a substrate such as a glass surface, and the film formed on the surface of the substrate has poor durability, and there is a problem that the water repellency is reduced within a short period of time.

[0004] In order to solve such a problem,
Water repellents using silane compounds and acid catalysts have been proposed. For example, JP-A-5-31156 discloses a water-repellent agent in which a fluoroalkylsilane, an acid catalyst and water are added to an alcohol solution.

According to this water-repellent treatment agent, when applied to the surface of a substrate such as a glass surface, the hydrolyzed portion of silane reacts with the glass surface by the action of an acid catalyst contained in the water-repellent treatment agent. In addition, there is an advantage that durability is extremely good and water repellency is maintained for a long time.

However, in the case of this water-repellent treatment agent, if unreacted silane is present on the surface of the substrate after coating, glare will occur. This must be removed, and after application, a wiping agent such as alcohol must be used. The work of wiping the base material surface had to be performed.

Although a wiping operation can be performed without using a wiping agent, considerable labor is required to remove unreacted silane from the substrate surface.

On the other hand, a water-repellent treatment agent has been proposed which enables a wiping operation without using a wiping agent. This water-repellent agent is obtained by mixing a wiping powder made of an oil-absorbing resin such as silica into the water-repellent agent.

However, in the case of this water-repellent agent, the powder settles in the container of the water-repellent agent, so that the powder is applied to the surface of the substrate in order to obtain a predetermined wiping effect. There has been the complication that the powder must be present in the treating agent and that it must be shaken with stirring each time it is used. In addition, when applied, in the portion where the powder is interposed between the surface of the base material and the treating agent, there is a problem that the reaction with silane is easily inhibited, and good reactivity and a strong film cannot be formed.

For this reason, in order to ensure sufficient reactivity, it is necessary to add an extra amount of silane to facilitate the reaction. Naturally, many unreacted silanes exist on the substrate surface. However, the objective of eliminating the original complicated wiping operation could not be sufficiently achieved.

The present invention has been made in view of the above problems, and has as its object to provide a water-repellent agent and a water-repellent treatment method capable of removing unreacted silane compounds by wiping after coating and drying. It is assumed that.

[0012]

Means for Solving the Problems To achieve the above object, an invention according to claim 1 is a water-repellent treating agent obtained by dissolving or dispersing a silane compound in a solvent, wherein the silane compound has the following chemical formula: As shown, the terminal M ₁ , M ₂ ,
Some or all of M ₃ is not a hydroxyl group, and the water repellent agent, characterized in that the unreacted silane compound after coating and drying is to allow the water wiping removed as its gist.

Embedded image

According to a second aspect of the present invention, there is provided a water repellent agent characterized in that the water repellent agent according to the first embodiment contains a polymerization terminator.

According to a third aspect of the present invention, the silane compound is
The gist of the present invention is a water-repellent agent characterized in that a part or all of the methoxy group of heptadecafluorodecyltrimethoxysilane is substituted with a hydroxyl group.

According to a fourth aspect of the present invention, the water-repellent agent according to the first, second or third aspect is applied and dried, and then the unreacted silane compound is wiped off with water. The treatment method is summarized.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the water repellent and the water repellent of the present invention will be described in more detail. The water-repellent treatment agent of the present invention contains, as shown in the following chemical formula, a terminal M ₁ ,
A part or all of M ₂ and M ₃ is a hydroxyl group, and a silane compound which is capable of removing the unreacted silane compound after coating and drying by wiping with water is dissolved or dispersed.

Embedded image

Examples of the silane compound include vinyltrichlorosilane, vinyltris (β-methoxyethoxy) silane,
Vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane,
β- (3,4 epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropylmethyldimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane ,

Chlorosilanes such as methyltrichlorosilane, methyldichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, phenyltrichlorosilane, diphenyldichlorosilane, tetramethoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane,
Phenyltrimethoxysilane, diphenyldimethoxysilane, tetraethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, diphenyldiethoxysilane, isobutyltrimethoxysilane, alkoxysilane such as decyltrimethoxysilane,

CF ₃ CH ₂ CH ₂ Si (OMe) ₃ , CF ₃
CH ₂ CH ₂ SiCl ₃ , CF ₃ (CF ₂ ) ₅ CH ₂ CH ₂ Si
Cl ₃ , CF ₃ (CF ₂ ) ₅ CH ₂ CH ₂ Si (OMe) ₃ ,
CF ₃ (CF ₂ ) ₇ CH ₂ CH ₂ SiCl ₃ , CF ₃ (CF ₂ )
₇ CH ₂ CH ₂ Si (OMe) ₃ , CF ₃ (CF ₂ ) ₇ CH ₂ C
H ₂ SiMeCl ₂ , CF ₃ (CF ₂ ) ₇ CH ₂ CH ₂ SiM
fluoro Al silanes such as e (OMe) _2, Me ₂
Si (OMe) ₂ , MeSi (OMe) ₃ , Me ₃ SiN
Silane for electronics such as HSiMe ₃ , HSCH ₂ CH ₂ CH ₂ Si (OMe) ₃ ,

Γ- (2-aminoethyl) aminopropyltrimethoxysilane, γ- (2-aminoethyl) aminopropylmethyldimethoxysilane, aminosilane, γ-
Methacryloxypropyltrimethoxysilane, N-β-
(N-vinylbenzylaminoethyl) -γ-aminopropyltrimethoxysilane hydrochloride, γ-glycidoxypropyltrimethoxysilane, aminosilane, γ-mercaptopropyltrimethoxysilane, methyltrimethoxysilane, vinyltriacetoxysilane, γ-chloropropyltrimethoxysilane, hexamethyldisilazane, γ
-Aminopropyltrimethoxysilane, vinyltrimethoxysilane, dimethyldimethoxysilane, octadecyldimethyl (3- (trimethoxysilyl) propyl) ammonium chloride, γ-mercaptopropylmethyldimethoxysilane, hydroxypropyltrimethoxysilane, γ-ureidopropyltri Ethoxysilane, γ-dibutylaminopropyltrimethoxysilane, phenyltrimethoxysilane, dimethyldiethoxysilane, trimethylmethoxysilane, n-decyltrimethoxysilane,
Examples include isoptyltrimethoxysilane, trimethylethoxysilane, γ-diallylaminopropyltrimethoxysilane, n-hexadecyltrimethoxysilane, n-octadecyltrimethoxysilane, and γ-methacryloxypropylmethyldimethoxysilane.

The terminal M ₁ of these silane compounds,
Part or all of M ₂ and M ₃ are hydroxyl groups (silanol groups). Therefore, the silane compound easily reacts with and binds to the hydroxyl group on the surface of the substrate such as glass, and forms a highly durable water-repellent film on the surface of the substrate.

The silane compounds existing on the surface of the substrate without reacting with the surface of the substrate are also used for the terminal M ₁ , M ₂ ,
Since some or all of M ₃ is a hydroxyl group (silanol group) may affinity with water, by wiping with water, it can be easily removed from the substrate surface.

As a method for producing a silane compound having such a structure, a conventionally known hydrolysis method, for example, an acid such as hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, formic acid, oxalic acid, acetic acid, sulfonic acid, etc. Particularly preferably, hydrochloric acid or nitric acid is used as a catalyst, water is added to the acid catalyst to form a mixed solution, and the mixed solution is added to a solvent in which the silane compound is dissolved or dispersed to hydrolyze the silane compound. Can be mentioned.

Examples of the solvent in which the silane compound is dissolved or dispersed include alcohols such as methyl alcohol, ethyl alcohol, butyl alcohol, and isopropyl alcohol, as well as halogenated hydrocarbons, aromatic hydrocarbons, and aliphatic hydrocarbons. Can be mentioned. The content of the silane compound in this solvent is not particularly limited.

The water-repellent treatment agent includes glycols such as ethylene glycol, propylene glycol and triethylene glycol, carbon tetrachloride, gasoline, hexane and acetone for the purpose of maintaining quality and improving workability. , Toluene, methyl ethyl ketone, xylene, butyl acetate, or a fungicide, a fragrance, a coloring agent, or the like can also be added.

The water-repellent agent can be suitably used for, for example, glass or metal, as well as resin plates, sheets or films made of polycarbonate used for eyes or optics. .

As described above, the silane compound in the water-repellent treatment agent of the present invention may be prepared by using one of the terminal M ₁ , M ₂ and M ₃ , for example, when M ₁ is a hydroxyl group, and Any _{two of} M ₁ , M ₂ and M ₃ , for example, when M ₁ and M ₂ are hydroxyl groups, and when all of the terminal M ₁ , M ₂ and M ₃ are hydroxyl groups There is. When viewed from the viewpoint of the reactivity with the substrate surface, the terminal M ₁ , M ₂ , M ₃ is the most reactive when all of the hydroxyl groups are hydroxyl groups, as the number of hydroxyl groups in the compound decreases The reactivity will decrease.

On the other hand, when the stability of the silane compound in the water-repellent treatment agent is examined, the compound having no hydroxyl group in the compound is most stable. However, the effect cannot be obtained. Therefore, as in the present invention, the terminal M ₁ , M ₂ , M ₃
Is partially or entirely substituted with a hydroxyl group. In this case, the stability is impaired as the number of hydroxyl groups increases. That is, the silane compound in which some or all of the terminal M ₁ , M ₂ , and M ₃ are hydroxyl groups is stored (in the container)
, It may cause a situation in which it cannot be used as a water repellent. Such a problem is remarkable, for example, when exposed to a high temperature or when stored for a long time.

For this reason, it is desirable to add a polymerization terminator to the treatment agent so that the silane compound is not polymerized during storage and can be used in a more stable state.

Next, the water repellent treatment method of the present invention will be described. This method is characterized in that the above-mentioned water-repellent agent is applied to the surface of a substrate, and after drying, unreacted silane compounds are wiped off with water. Note that the silane compound used in this method is as described above, and the substrate to which the method is applied is, as described above, other than glass and metal, and polycarbonate used for ophthalmic and optical purposes. The material is a resin plate or the like, and the description is omitted here.

For applying the water-repellent treatment agent to the substrate, a conventionally known coating method such as a dipping method, a spraying method, a spin coating method, or a flow coating method is used in addition to brush coating or coating with an impregnated cloth. be able to.

Drying is 100 to 200 ° C in addition to natural drying.
The method of heating the application surface at the above temperature may be employed. By applying the water-repellent treatment agent to the surface of the base material and drying it in this manner, a part or all of the terminal M ₁ , M ₂ , and M ₃ hydroxyl groups (silanols) of the silane compound contained in the water-repellent treatment agent ) Easily reacts with and binds to a hydroxyl group on the surface of a base material such as glass to form a highly durable water-repellent film.

The surface of the substrate on which the water-repellent film is formed has no unreacted
Is present. Unreacted surface on the substrate surface
If run compounds remain, glare will occur.
Need to be removed. In this method, unreacted silane
For compounds, the terminal M ₁ , M_Two, M_ThreePart or all of
Part is a hydroxyl group (silanol group),
Good affinity, wipe the surface of the substrate with a wet cloth
By doing so, the unreacted silane compound can be easily removed from the substrate surface.
Can be removed.

[0034]

【Example】

Example 2 g of a silane compound in which part or all of the methoxy group of heptadecafluorodecyltrimethoxysilane shown in the following formula was substituted with a hydroxyl group,

Embedded image It was added to 100 g of isopropyl alcohol to obtain a water-repellent agent.

Comparative Example Similarly, heptadecafluorodecyltrimethoxysilane which was not substituted with a hydroxyl group was used, and 2 g of this silane was added to 100 g of isopropyl alcohol to obtain a water-repellent agent.

The water-repellent treatment agents of the above Examples and Comparative Examples were applied to a glass surface, and after drying, water wiping properties, wiping properties with isopropyl alcohol (IPA), and wiping properties with empty wiping were examined. Good is, bad is ×,
The performance of each water repellent agent was evaluated. Table 1 shows the results.

[0037]

From the above results, it can be seen that the water repellent of the comparative example cannot be removed without removing the unreacted silane compound by IPA, whereas the water repellent of the example can be removed by wiping with water. It was confirmed that it could be easily removed.

[0039]

According to the water-repellent agent and the water-repellent treatment method of the present invention, the water-repellent agent is a silane in which a part or all of the terminal M ₁ , M ₂ and M ₃ are hydroxyl groups. By dissolving or dispersing the compound in the solvent, by applying and drying this, a water-repellent film with high durability is formed, and the unreacted silane compound remaining on the substrate surface is also wiped with water. It has an excellent effect that it can be easily removed.

Claims (4)

[Claims] 1. A water-repellent treatment agent obtained by dissolving or dispersing a silane compound in a solvent, wherein the silane compound has a terminal M ₁ , M ₂ , M ₃ partially or entirely as shown in the following chemical formula. A water-repellent treatment agent having a hydroxyl group and capable of removing an unreacted silane compound after coating and drying by wiping with water. Embedded image 2. The water-repellent agent according to claim 1, further comprising a polymerization terminator. 3. The water-repellent treatment agent according to claim 1, wherein the silane compound is obtained by substituting a part or all of the methoxy group of heptadecafluorodecyltrimethoxysilane with a hydroxyl group. 4. A water-repellent treatment method comprising applying the water-repellent treatment agent according to claim 1, 2, or 3, and then drying and removing unreacted silane compounds with water.