JPH09221618A - Resin composition for water repelling coating - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an inexpensive resin composition for water repelling coating capable of forming by coating, excellent in adhesiveness to a base material and water repellency without attacked with an acidic rain. SOLUTION: This resin composition for water repelling coating comprises a polymer (A) which comprises 20-80wt.% of a fluorine-containing monomer (a) having a carbon to carbon double bond and a perfluoroalkyl group and 80-20wt.% of a monomer (b) having the carbon to carbon double bond and at least one functional group selected from an isocyano group, an epoxy group and an N-methylol group or an N-alkoxymethyl group and a hydroxyl group, and a polymer (B) which comprises the monomer (b) having at least one functional group selected from an isocyanate group, an epoxy group and N-methylol group or an N-alkoxymethyl group and hydroxyl group.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a water repellent coating.

[0002]

2. Description of the Related Art A water-repellent coating agent is applied to an article that causes inconvenience due to the adhesion of water to prevent the adhesion of water droplets. For example, a water-repellent coat called a liquid wiper is well known in order to repel water drops adhering to the windshield, door glass, door mirrors, etc. in the case of rain and to secure the field of view without using a wiper.
However, since the water-repellent coating film obtained with this liquid wiper has poor durability, the water repellency cannot be maintained unless it is applied regularly. Furthermore, although liquid wipers have poor acid resistance, acid rain is now a problem, and automobile materials are also required to have acid rain resistance. Various fluorine-containing compounds have been proposed to solve these problems. To obtain sufficient water repellency, the compound must contain a large amount of fluorine, but since fluorine is expensive, the cost of the material increases. There was a drawback that it would end up.

[0003]

DISCLOSURE OF THE INVENTION The object of the present invention is to provide excellent adhesion to a base material, excellent weather resistance, excellent acid resistance, and resistance to acid rain, and a low fluorine content, which makes it inexpensive. It is to provide a resin composition for water coating.

[0004]

DISCLOSURE OF THE INVENTION The present inventors utilize the localization of a fluoropolymer on the surface of a coating film to utilize an isocyano group, an epoxy group, an N-methylol group or an N-methylol group.
A polymer having at least one functional group selected from an alkoxymethyl group and a hydroxyl group, an isocyano group,
By mixing a copolymer having at least one functional group selected from an epoxy group, an N-methylol group, an N-alkoxymethyl group, or a hydroxyl group and a perfluoroalkyl group, water repellency can be obtained with a small fluorine content. We have succeeded in forming a coating film that is high and has excellent weather resistance. That is, the present invention provides a fluorine-containing monomer (a) 20 having a carbon-carbon unsaturated double bond and a perfluoroalkyl group.
To 80% by weight, and a monomer having a carbon-carbon unsaturated double bond and at least one functional group selected from an isocyano group, an epoxy group, an N-methylol group, an N-alkoxymethyl group, and a hydroxyl group (b ) A polymer (A) consisting of 80 to 20% by weight, a carbon-carbon unsaturated double bond and an isocyano group, an epoxy group, an N-methylol group, or
A resin composition for water-repellent coating, comprising a polymer (B) comprising a monomer (b) having at least one functional group selected from an N-alkoxymethyl group and a hydroxyl group. To do.

Further, the above water-repellent coating is characterized in that the fluorine-containing monomer (a) is 0.1 to 10% by weight based on the total of the polymer (A) and the polymer (B). It relates to a resin composition. Further, the present invention relates to the above water-repellent coating, which is dissolved in a solvent containing no halogen atom. Further, the present invention relates to the above water-repellent coating containing 1 to 40% by weight of the silane coupling agent based on the total of the polymer (A) and the polymer (B). Further, the organosilica sol is added to the polymer (A) and the polymer (B) in an amount of 1
The above water repellent coating comprises 0 to 80% by weight.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION As an example of the fluorine-containing monomer (a) having a perfluoroalkyl group having a carbon-carbon unsaturated double bond used in the component (A) constituting the present invention, 2-
Perfluoroisononylethyl (meth) acrylate,
2-perfluorononylethyl (meth) acrylate, 2-
Perfluorodecylethyl (meth) acrylate, 2-perfluorobutylethyl (meth) acrylate, perfluoromethylmethyl (meth) acrylate, perfluoroethylmethyl (meth) acrylate, perfluorobutylmethyl (meth) acrylate, perfluorooctyl Methyl (meth) acrylate, perfluorodecylmethyl (meth) acrylate, perfluorobutylethyl (meth) acrylate, perfluorooctylethyl (meth) acrylate, perfluorodecylethyl (meth) acrylate, perfluoropropylpropyl (meth) acrylate , Perfluorooctylpropyl (meth) acrylate, perfluorooctylamyl (meth) acrylate, perfluorooctylundecyl (meth) acrylate, etc. Perfluoroalkyl (meth) acrylate having a perfluoroalkyl group having 1 to 20 carbon atoms,

Perfluorobutyl ethylene, perfluorohexyl ethylene, perfluorooctyl ethylene,
Perfluorodecyl ethylene and the like can be mentioned, and one of these can be used or a mixture of two or more of them can be used according to the required performance, and they are used at a copolymerization ratio of 20 to 80% by weight, but have sufficient water repellency. In order to obtain the above, it is desirable to copolymerize 40% by weight or more, and in order to dissolve it in a solvent containing no halogen atom, it is desirable to use a copolymerization ratio of 60% by weight or less.

The carbon-carbon unsaturated double bond used in the components (A) and (B) constituting the present invention and selected from an isocyano group, an epoxy group, an N-methylol group, an N-alkoxymethyl group, and a hydroxyl group. The monomer (b) having at least one kind of functional group is used to crosslink after coating to form a hard coating film.

Examples of the monomer (b) having an isocyano group include (meth) acryloyloxyethyl isocyanate, (meth) acryloyloxypropyl isocyanate, 2-hydroxyethyl (meth) acrylate and 4-hydroxybutyl. Examples thereof include those obtained by reacting hydroxy (meth) acrylate such as (meth) acrylate with polyisocyanate such as toluene diisocyanate, isophorone diisocyanate, and Coronate L. Examples of the monomer (b) having an epoxy group include glycidyl methacrylate, glycidyl cinnamate, glycidyl allyl ether, glycidyl vinyl ether, vinylcyclohexane monoepoxide, 1,3-butazinene monoepoxide and the like.

Further, examples of the monomer (b) having an N-methylol group or an N-alkoxymethyl group include N-
N-monoalkoxymethyl groups such as methylol (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-ethoxymethyl (meth) acrylamide, N-propoxymethyl (meth) acrylamide, and N-butoxymethyl (meth) acrylamide (Meth) acrylamide, N, N-dimethylol (meth) acrylamide, N, N-di (methoxymethyl) (meth)
Acrylamide, N, N-di (ethoxymethyl) (meth) acrylamide, N, N-di (propoxymethyl)
(Meth) acrylamide having an N, N-dialkoxymethyl group such as (meth) acrylamide and N, N-di (butoxymethyl) (meth) acrylamide.

Further, a monomer (b) having a hydroxyl group
Examples of 2-hydroxyethyl (meth) acrylate, 1-hydroxypropyl (meth) acrylate,
2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, polytetramethylene glycol mono (meth) acrylate and the like can be mentioned.

Depending on the required performance, one or more of these can be used in combination. Further, the one used in the polymer (A) and the one used in the polymer (B) are not necessarily required to be the same. The monomer (b) is used in the polymer (A) at a copolymerization ratio of 80 to 20% by weight. If less than 20% by weight,
If sufficient hardness is not obtained and it is more than 80% by weight,
Water repellency decreases. Further, in the polymer (B), 20 to 20
Used at a copolymerization ratio of 100% by weight. If it is less than 20% by weight, sufficient hardness cannot be obtained.

The polymer (A) and the polymer (B) can be obtained by a known method such as solution polymerization. As the solvent used, methanol, ethanol, propanol, butanol, ethylene glycol methyl ether, alcohols such as diethylene glycol methyl ether, acetone, methyl ethyl ketone, methyl isobutyl ketone, ketones such as cyclohexanone, tetrahydrofuran,
Ethers such as dioxane, ethylene glycol dimethyl ether, ethylene glycol dimethyl ether,
Hydrocarbons such as hexane, heptane and octane, aromatics such as benzene, toluene, xylene and cumene, and esters such as ethyl acetate and butyl acetate can be used. The solvent may be a mixture of two or more. The charged concentration of the monomer at the time of synthesis is preferably 1 to 80% by weight.

As the polymerization initiator, a usual peroxide or azo compound, for example, benzoyl peroxide, azoisobutylvalenonitrile, azobisisobutyronitrile, di-t-butylperoxide, t-butylperbenzoate, T-butyl peroctoate, cumene hydroxyperoxide, etc. are used, and the polymerization temperature is 50 to 140.
° C, preferably 70 to 140 ° C. The preferred average molecular weight of the obtained polymer is 2,000 to 100,000 for both the polymer (A) and the polymer (B).

In the present invention, in order to promote crosslinking of at least one functional group selected from an isocyano group, an epoxy group, an N-methylol group, an N-alkoxymethyl group and a hydroxyl group in the composition, A catalyst may be added. When a monomer (b) having an isocyano group is used as a typical catalyst, triethylamine, N, N, N ′, N′-tetramethyl-1,3-butanediamine, diethanolamine, dibutyltin dilaurylate is used. , Dibutyltin di (2-ethylhexoate) and the like are preferable. Further, in the case of the monomer (b) having an epoxy group, sodium hydroxide, lithium chloride, diethyl zinc, tetra (n-butoxy) titanium, triethylamine, N, N-dimethylbenzylamine and the like are preferable.

When the monomer (b) having an N-methylol group or an N-alkoxymethyl group is used, p
-Toluenesulfonic acid, phthalic anhydride, benzoic acid, benzenesulfonic acid, dodecylbenzenesulfonic acid, formic acid,
Itaconic acid, oxalic acid, maleic acid, and their ammonium salts, lower amine salts, polyvalent metal salts and the like are preferable. When the monomer (b) having a hydroxyl group is used, p-toluenesulfonic acid, phthalic anhydride, benzoic acid, benzenesulfonic acid, dodecylbenzenesulfonic acid, formic acid, itaconic acid, oxalic acid, maleic acid Are preferred. The amount of these catalysts used is in the range of 0.01 to 10% by weight, preferably 0.1 to 5% by weight, based on 100% by weight of the paint.

Further, in the present invention, a silane coupling agent can be used if necessary.
Specific examples of the silane coupling agent include tetrafunctional silanes such as tetramethoxysilane and tetraethoxysilane,
Methyltrimethoxysilane, methyltriethoxysilane, γ-chloropropyltrimethoxysilane, vinyltrimethoxysilane, γ-methacryloyloxypropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-gly Trifunctional silanes such as cydoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ-morpholinopropyltrimethoxysilane, and a part of the above trifunctional silanes is an alkyl group or phenyl group. , A bifunctional silane substituted with a vinyl group or the like, for example, dimethyldimethoxysilane, phenylmethyldimethoxysilane, vinylmethyldimethoxysilane, γ-chloropropylmethyldimethoxysilane, γ
-Glycidoxypropylmethyldimethoxysilane and the like. In addition, hydrolysates and partial condensates of these compounds can be used. The silane coupling agent is used in an amount of 1 to 1 based on the total of the polymer (A) and the polymer (B).
It is used in an amount of 40% by weight, preferably 3-20% by weight.

Further, in the present invention, an organosilica sol can be used if necessary. The organosilica sol is a colloid solution in which colloidal silica is stably dispersed in an organic solvent. As a typical example, for example, a trade name IPA- manufactured by Nissan Chemical Industry Co., Ltd.
ST, MIBK-ST, MA-ST-M, EG-ST,
EG-ST-ZL, NPC-ST, DMAC-ST, D
MAC-ST-ZL, XBA-ST, methanol silica sol and the like. The organosilica sol is used in an amount of 10 to 80% by weight, preferably 20 to 60% by weight, based on (A) and (B) of the present invention. If it is less than this range, the effect of improving water repellency is small, and if it exceeds this range, the adhesion to the substrate is impaired.

In the present invention, a filler, a thixotropy-imparting agent, a coloring pigment, an extender pigment, a dye, an antioxidant, an antioxidant, an antistatic agent, a flame retardant, if necessary, within a range that does not impair the effects of the present invention. Various additives such as a thermal conductivity improver, a plasticizer, an anti-sagging agent, an antifouling agent, an antiseptic, a bactericide, a defoaming agent, a leveling agent, and a curing agent may be added.

The water-repellent coating of the present invention is obtained by mixing and dissolving the polymer (A), the polymer (B), and if necessary, the silane coupling agent, the catalyst and the additive in a solvent. Solvents are methanol, ethanol, propanol,
Alcohols such as butanol, ethylene glycol methyl ether, diethylene glycol methyl ether,
Acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and other ketones, tetrahydrofuran, dioxane, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether and other ethers, hexane, heptane, octane and other hydrocarbons, benzene, toluene, xylene, cumene and other aromas Depending on the composition of the resin, it is selected from the group consisting of esters such as ethyl acetate and butyl acetate. Two or more kinds of solvents may be used.

The mixing method is not particularly limited, but normally, the polymer solution used at the time of polymerization may be mixed as it is and stirred with a stirring blade, a shaking stirrer, a permeation stirrer, a rotary stirrer or the like. In order to improve coatability and the like, a solvent may be further added or concentrated. Further, the mixing ratio of the polymer (A) and the polymer (B) is such that the fluorine-containing monomer (a) is 0.1 to 10% by weight based on the total amount of the polymer (A) and the polymer (B).
It is preferable that If it is less than 0.1% by weight, a sufficient water-repellent effect cannot be obtained, and if it is more than 10% by weight, sufficient coating film hardness cannot be obtained and the cost becomes high. The water-repellent coating thus obtained is used for automobile windshields, rear glass, door glass, fender mirrors, door mirrors and glass for transportation equipment such as railroads and airplanes, as well as window glass for high-rise buildings, plastics and various other materials. It is applied to places where water repellency is required, such as films, metals, concrete, and ceramic products, and a water repellent coating excellent in adhesion, hardness, acid resistance, etc. is formed. The application method is not particularly limited, but application can be made by dip coating, spray coating, brush coating, or the like.
Painted water repellent coating is air-dried or 30-22
A tough water-repellent coating film can be obtained by heating at 0 ° C. for several seconds to several weeks.

[0022]

EXAMPLES Next, examples of the present invention will be described more specifically. All parts in the examples are parts by weight. All the synthesis was performed under a nitrogen atmosphere. Synthesis methods of Examples 1 to 4 and Comparative Example 1 Two four-necked flasks equipped with a cooling pipe, a stirrer, a thermometer, and a nitrogen introduction pipe were prepared, and the components A and B were separately shown in Table 1. Based on the compounding ratio shown, 200 parts of isopropyl alcohol was charged as the solvent, the temperature was raised to 80 ° C. with stirring, and 1.6 parts of azobisisobutyronitrile was added.
Polymerization reaction was carried out for 2 hours, 0.4 part of azobisisobutyronitrile was further added, and polymerization was carried out for 2 hours to obtain a polymer solution.

The polymer solution of the component A and the polymer solution of the component B thus obtained were converted to a solid content of 1:99.
At a rate of In Comparative Example 1, the A component was synthesized so that the fluorine content was equal to the fluorine content in the entire composition of Example 1, and only the A component was used alone. Each of the compounds shown in Table 2 was used as a crosslinking catalyst at 1% based on the solid content of the solution
And then ethyl acetate was added to obtain a coating liquid having a solid content of 10%. 1 mil of this coating solution on a glass plate with a thickness of 1.3 mm
It was applied with the applicator and was left at room temperature for 30 minutes. Then, it was baked in an oven at 200 ° C. for 10 minutes to obtain a water-repellent coated glass plate.

[0024]

[Table 1]

[0025]

[Table 2] ────────────────────────────────── Crosslinking agent ────────── ──────────────────────── Example 1 Dibutyltin dilaurylate Example 2 N, N-Dimethylbenzylamine Example 3 p-Toluenesulfonic acid Example 4 p-Toluenesulfonic acid Comparative Example 1 Dibutyltin dilaurate ────────────────────────────────── Comparative Example 2 Commercially available The liquid wiper described above was applied to a degreased and washed glass plate by a specified method to obtain a water-repellent coated glass plate. Comparative Example 3 The water-repellent glass prepared in Comparative Example 2 was heated in an oven at 200 ° C for 10 days.
After baking for a minute, a glass plate having the water-repellent coating sufficiently cured was obtained.

Various tests were conducted on the water-repellent coated glass plate thus prepared. The test method is as follows. Contact angle: The contact angle of the water-repellent coating film to pure water was measured with a contact angle meter. Weather resistance: Sunshine fade meter (Sunshine super long carbon arc light source, discharge voltage current 50
The contact angle of the coating film, which had been left for 300 hours in V-60A, 30 ° C., about 50% RH), with pure water was measured with a contact angle meter. Product%
Indicated by Acid resistance: The state of the coating film after being soaked in a 5% sulfuric acid solution at room temperature for 4 hours was visually evaluated. The test results are shown in Table 3.

[0027]

[Table 3] ────────────────────────────────── Sample contact angle (°) Acid resistance Coating 300 After time ────────────────────────────────── Example 1 112 110 Good Example 2 107 102 Good Example 3 108 105 Good Example 4 114 109 Good Comparative Example 1 68 67 Good Comparative Example 2 93 68 Bad Comparative Example 3 92 72 Bad ─────────────────────── ─────────────

[0028]

As described above, the present invention has at least one functional group selected from an isocyano group, an epoxy group, an N-methylol group, an N-alkoxymethyl group and a hydroxyl group and a side chain of a perfluoroalkyl group. By using a mixture of the polymer having in (1) and a polymer having at least one functional group selected from an isocyano group, an epoxy group, an N-methylol group, an N-alkoxymethyl group and a hydroxyl group, a very small amount can be obtained. Despite containing only fluorine, it has high water repellency, excellent adhesion to base materials, excellent weather resistance, excellent acid resistance, is not attacked by acid rain, and has a low fluorine content. It was possible to obtain an inexpensive resin composition for water-repellent coating.

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[Procedure amendment]

[Submission date] April 14, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Deleted

[Correction contents]

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION As an example of the fluorine-containing monomer (a) having a perfluoroalkyl group having a carbon-carbon unsaturated double bond used in the component (A) constituting the present invention, 2-
Perfluoroisononylethyl (meth) acrylate,
2-perfluorononylethyl (meth) acrylate, 2-
Perfluorodecylethyl (meth) acrylate, 2-perfluorobutylethyl (meth) acrylate, perfluoromethylmethyl (meth) acrylate, perfluoroethylmethyl (meth) acrylate, perfluorobutylmethyl (meth) acrylate, perfluorooctyl Methyl (meth) acrylate, perfluorodecylmethyl (meth) acrylate, perfluorooctylethyl (meth) acrylate, perfluoropropylpropyl (meth) acrylate, perfluorooctylpropyl (meth) acrylate, perfluorooctylamyl (meth) acrylate , Perfluorooctylundecyl (meth) acrylate, etc., having a perfluoroalkyl group having 1 to 20 carbon atoms

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location C09D 133/16 PFY C09D 133/16 PFY C09K 3/18 102 C09K 3/18 102 104 104 104

Claims (5)

[Claims] 1. A fluorine-containing monomer (a) having 20 to 80% by weight of a carbon-carbon unsaturated double bond and a perfluoroalkyl group, and a carbon-carbon unsaturated double bond and an isocyano group,
Polymer (A) consisting of 80 to 20% by weight of a monomer (b) having at least one functional group selected from an epoxy group, an N-methylol group, an N-alkoxymethyl group, or a hydroxyl group, and carbon carbon. Polymer (B) comprising a monomer (b) having an unsaturated double bond and at least one functional group selected from an isocyano group, an epoxy group, an N-methylol group, an N-alkoxymethyl group, or a hydroxyl group. A resin composition for water-repellent coating, comprising: 2. The fluorine-containing monomer (a) is 0.1 to 10% by weight based on the total of the polymer (A) and the polymer (B). Resin composition for water-repellent coating. 3. A water-repellent coating obtained by dissolving the resin composition for water-repellent coating according to claim 1 or 2 in a solvent containing no halogen atom. 4. The water-repellent coating according to claim 3, which further comprises a silane coupling agent in an amount of 1 to 40% by weight based on the total amount of the polymer (A) and the polymer (B). 5. An organosilica sol is further added to the polymer (A).
And 10 to 80% by weight based on the total of the polymer (B).