JPH03181540A - Water-based fluororesin composition - Google Patents

Abstract

PURPOSE:To obtain the title composition excellent in storage stability, chroma, transparency and the adhesivity to substrates, capable of giving films of high weatherability by dissolving in an aqueous medium a copolymer reaction product from a specific fluorine-contg. resin and a monomer component containing an acid group-contg. vinyl monomer. CONSTITUTION:The objective composition can be obtained by dissolving in an aqueous medium a copolymer reaction product from (A) a fluorine-contg. resin containing in one molecule both acid group and reactive unsaturated double bond prepared by reaction between (1) a hydroxyl group-contg. fluororesin, (2) an acid anhydride containing reactive unsaturated double bond [pref. (meth)acrylic anhydride] and (3) a reactive unsaturated double bond-free acid anhydride (e.g. adipic anhydride) and (B) a monomer component containing an acid group-contg. vinyl monomer [e.g. (meth)acrylic acid].

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a novel and useful aqueous fluororesin composition. More specifically, the present invention comprises dissolving a copolymerization reaction product of a fluororesin having a specific functional group and a monomer having a specific functional group in an aqueous medium.
In particular, the present invention relates to an aqueous fluororesin composition that has excellent storage stability and can provide a film having excellent weather resistance.

The aqueous fluororesin composition of the present invention can be used in a wide range of applications, including not only paints but also water-based inks, adhesives, sealants, and the like.

[Conventional technology]

Conventionally, various synthetic resin paints have been developed for the purpose of surface protection and beautification. Fluororesin paints have received particular attention in recent years as they have long-term weather resistance. Fluororesin paints are usually composed of a fluororesin, pigments, various additives, and organic solvents. This conventional fluororesin composition uses an organic solvent as a medium, which causes the solvent to volatilize into the working atmosphere, worsening the working environment, impairing human safety such as solvent poisoning for workers, and reducing air pollution. It pollutes and, being a flammable solvent, has always been a fire and explosion hazard.

In order to solve such problems, a method is known in which a fluororesin is synthesized by emulsion polymerization using an emulsifier (Japanese Patent Application Laid-Open No. 55-25412). However, with this method,
Since the emulsion polymerization reaction is carried out in water, it is difficult to use large amounts of highly polar monomers, and the resulting emulsion has problems with film-forming properties, and also has poor water resistance due to the residual emulsifier. However, it has drawbacks such as poor corrosion resistance and adhesion, and also has problems with storage stability.

In addition, for the purpose of imparting hydrophilicity to the fluororesin and improving dispersibility, etc., a hydroxyl group-containing fluororesin is reacted with a specific tribasic acid anhydride, and in a -stage reaction, directly
A technique for producing a carboxyl group-containing fluororesin by introducing a carboxyl group has also been proposed (Japanese Patent Application Laid-Open No. 58-136).
Furthermore, a technique has also been proposed in which this carboxyl group-containing fluororesin is neutralized to form a water-dispersed resin and used as an electrodeposition paint (Japanese Patent Laid-Open No. 62-5967).
Publication No. 6).

[Problem to be solved by the invention]

However, all of these methods only obtain carboxyl group-containing fluororesins within the limited range of water-dispersed resins, and there are currently no methods that have been used for water-soluble fluororesins. is the reality.

However, under this technical background, the present inventors
In order to obtain a water-soluble fluororesin, and a water-based fluororesin with excellent weather resistance, we began intensive research.

Therefore, the problem to be solved by the present invention is to provide a film that has not only weather resistance, but also good color saturation and transparency, excellent adhesion to substrates, and water resistance. An object of the present invention is to provide an extremely useful aqueous fluororesin composition that has excellent physical properties.

As described above, the present invention basically aims to provide an extremely useful water-based fluororesin that can provide a film that is no different from conventional solvent-based fluororesins.

[Means for Solving the Problems] Therefore, the present inventors focused on the problems to be solved by the invention as described above, and as a result of intensive studies, the present inventors added the following to the hydroxyl group site of the hydroxyl group-containing fluororesin: A reactive unsaturated double bond-containing acid anhydride and a reactive unsaturated double bond-containing acid anhydride are allowed to act together to first introduce reactive unsaturated double bonds and a certain proportion of acid groups. Then, by applying a polymerizable monomer containing an acid group-containing vinyl monomer as an essential component to the site of the reactive unsaturated double bond, an aqueous solution of an acid group-containing fluororesin with excellent performance, i.e. The present invention was completed by discovering that an aqueous fluororesin can be obtained efficiently.

That is, the present invention basically consists of a fluororesin (A) having both an acid group and a reactive unsaturated double bond in one molecule, and a fluorine-containing resin (B) containing an acid group-containing vinyl monomer. The present invention aims to provide an aqueous fluororesin composition in which a copolymerization reaction product with a basic substance is first neutralized with a basic substance and then dissolved in an aqueous medium.

Specifically, the present invention relates to a hydroxyl group-containing fluororesin (
a-1) and a reactive unsaturated double bond-containing acid anhydride (a-
2) and a reactive unsaturated double bond-containing acid anhydride (a-
3), a fluororesin (A) having both an acid group and a reactive unsaturated double bond in one molecule;
It is an object of the present invention to provide an aqueous fluororesin composition, which consists of dissolving a copolymerization reaction product with a hexamer (B) containing an acid group-containing vinyl monomer in an aqueous medium.

Here, first, the above-mentioned hydroxyl group-containing fluororesin (
As a-1), of course, any conventionally known fluorine-containing resin having at least one, preferably at least two hydroxyl groups in one molecule can be used. To exemplify only the most representative ones, a fluorine-containing vinyl monomer as listed below and a hydroxyl group-containing monomer or a monomer having a group convertible to a hydroxyl group by hydrolysis are used as essential components. and those obtained by copolymerizing other copolymerizable vinyl monomers.

Among the various monomers, we will exemplify only the most representative ones as fluorine-containing vinyl monomers (hereinafter also referred to as fluoroolefins or fluoroolefin monomers), such as vinyl fluoride, vinylidene fluoride, Trifluoroethylene, tetrafluoroethylene, chlorotrifluoroethylene, promotrifluoroethylene, pentafluoropropylene or hexafluoropropylene, or trifluoromethyl trifluorovinylether, pentafluoroethyl trifluorovinylether or heptafluoropropyl trifluoroethylene Examples include perfluoroalkyl perfluorovinyl ethers such as fluorovinyl ether, and among them, it is preferable to use tetrafluoroethylene, vinylidene butylene, chlorotrifluoroethylene, or hexafluoropropylene. These fluoroolefin monomers may be used alone or in combination of two or more.

Examples of hydroxyl group-containing monomers include 2-hydroxyethyl vinyl ether, 3-hydroxypropyl vinyl ether, 2-hydroxypropyl vinyl ether, 4-hydroxybutyl vinyl ether, 3-hydroxybutyl vinyl ether, 2-hydroxy-2-methylpropyl vinyl ether, and 5-hydroxybenzene. Vinyl ethers containing hydroxyl groups, such as rubinyl ether, 6-hydroxyhexyl vinyl ether, are preferably used.

Examples of monomers having a group that can be converted into a hydroxyl group by hydrolysis include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltripropoxysilane, vinylmethyljethoxysilane, vinyltris(β-methoxyethoxy)silane, and allyltrimethoxysilane. , trimethoxysilylethyl vinyl ether, methyldimethoxysilylethyl vinyl ether, trimethoxysilylpropyl vinyl ether, triethoxysilylpropyl vinyl ether, methyldimethoxysilylpropyl vinyl ether, γ-(meth)acryloyloxypropyltrimethoxysilane, r-(meth) Mention may be made of monomers containing hydrolyzable silyl groups such as acryloyloxypropyltriethoxysilane or γ-(meth)acryloyloxypropylmethyldimethoxysilane.

Other copolymerizable monomers include alkyl vinyl ethers or substituted alkyl vinyl ethers,
Cycloalkyl vinyl ethers, carboxylic acid vinyl esters, α-olefins, various halogenated olefins except fluoroolefins, aromatic vinyl compounds,
Typical examples include methacrylic esters and acrylic esters.

In addition, particularly suitable examples of the hydroxyl group-containing fluororesin (a-1) include those manufactured by Dainippon Ink and Chemicals Co., Ltd.
-700J and the like are available in the fluoronate produced by the company.The hydroxyl value of this hydroxyl group-containing fluororesin is preferably within the range of 10 to 200, and particularly preferably within the range of 20 to 150.When this hydroxyl value is less than 10 is not preferable because the dispersion stability of the copolymerization reaction product, that is, the so-called acid group-containing copolymer, in an aqueous medium tends to be poor.On the other hand, when the hydroxyl value exceeds 200, excessive Because of the number of hydroxyl groups in the number of hydroxyl groups, the water resistance of the resulting coating film decreases, which is not preferred.

The above-mentioned reactive unsaturated double bond-containing acid anhydride (a-2)
Of course, any compound having such a double bond can be used, but it is particularly desirable to use acrylic anhydride and/or methacrylic anhydride.

Next, the above-mentioned reactive double bond-free acid anhydride (a-
As for 3), of course, anything other than the acid anhydride (a2) can be used, but to exemplify only typical ones, succinic anhydride, adipic anhydride, anhydride These include glutaric acid, 1,2-cyclohexane dicarboxylic anhydride, cis-4-cyclohexane-1,2-dicarboxylic anhydride, phthalic anhydride, or naphthalene dicarboxylic anhydride.

The fluororesin (A) having both an acid group and a reactive unsaturated double bond in one molecule used in preparing the aqueous fluororesin composition of the present invention is as listed above. , respectively, hydroxyl group-containing fluororesin (a-1) and reactive unsaturated double bond-containing acid anhydride (a-
2) and reactive unsaturated double bond-containing acid anhydride (a
-3), but at that time,
The amount of each of these components used is 90% for resin (a-1).
~98% by weight, acid anhydride (a2) is 0.1
2 to 2% by weight, acid anhydride (a-3) is 2 to 1% by weight.
They are appropriately selected and set within the weight range of 0% weight and so that the total amount of each of these components is 100% by weight.

If the amount of the acid anhydride (a-2> used is less than 0.1% by weight, it is undesirable because the dispersion stability of the copolymerization reaction product in the aqueous medium tends to deteriorate. If the amount of acid anhydride (a-2) used exceeds 2% by weight, the copolymerization reaction product tends to have a high molecular weight during polymerization and tends to gel, which is not preferable.

When the reaction is carried out using, for example, methacrylic anhydride as the acid anhydride having this reactive unsaturated double bond, -QC-C=CI2 1 0 CH.

A reactant containing a vinyl group represented by is obtained.

Next, the polymerizable monomer used in the copolymerization reaction with the thus obtained fluororesin (A) having both an acid group and a reactive unsaturated double bond in one molecule. -(B) is a monomer containing an acid group-containing vinyl monomer. n&
There are no particular restrictions on the content of vinyl monomers, but
It is preferable that the content be at least about 5% by weight. If the content of the acid group-containing vinyl monomer is too small, the dispersion stability of the resin in an aqueous medium, the adhesion of the painted film to metals, and the solvent resistance tend to deteriorate, which is undesirable.

Typical examples of such acid group-containing vinyl monomers include acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid, and fumaric acid.

In addition, the most representative examples of polymerized 7-mer necks other than acid group-containing vinyl monomers include styrene,
Stretin monomers such as vinyltoluene, 2-methylstyrene, t-butylstyrene or chlorstyrene; methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, n-aryl acrylate , isoacrylic acid 0
, a2n-hexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, decyl acrylate or dodecyl acrylate; methyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate; Methacrylic esters such as n-amyl methacrylate, fin-hexyl methacrylate, a2n-octyl methacrylate, 2-ethylhexyl methacrylate, decyl methacrylate or dodecyl methacrylate; droxyethyl acrylate, hydroxypropyl acrylate, hydroxy methacrylate Hydroxyl group-containing monomers such as ethyl or hydroxypropyl methacrylate; or N
-N-substituted (meth)acrylic monomers such as -methylol (meth)acrylic acid or N-butoxymethyl (meth)acrylamide. Also, carboxylic acid vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl caproate, vinyl versatate, vinyl laurate, vinyl stearate or vinyl benzoate, or methyl, ethyl, n-propyl, isopropyl, Vinyl ethers having an alkyl group such as n-butyl, isobutyl, t-butyl, isoamyl, n-hexyl, n-octyl or 2-ethylhexyl, or a substituent-containing alkyl group such as hydroxyethyl or hydroxybutyl can be mentioned.

Thus, the copolymerization reaction product, which can also be called an acid group-containing modified polymer, is produced by, for example, solution polymerizing the fluororesin (A) and the polymerizable monomer (B).

At that time, the weight ratio of the fluororesin (A) and the polymerizable monomer (B) was 40:60 to 9.
A range of 5:5 is preferred. When the proportion of the fluorine-containing resin (A) used is less than 40% by weight, the fluorine copolymer has
This is not preferable because it may not be possible to take advantage of various characteristics.

On the other hand, the usage rate of this fluororesin (A) is 95% by weight.
If it exceeds this amount, the resulting copolymerization reaction product tends to be difficult to dissolve, which is not preferable.

Typical examples of the polymerization initiator used in the copolymerization reaction between the fluororesin (A) and the polymerizable monomer (B) include azobisisobutyronitrile and benzoyl peroxide. , ordinary radical polymerization initiators, etc.

Examples of particularly representative organic solvents used in the copolymerization reaction include alcohols such as methanol, ethanol, propatool, or butanol; methyl cellosolve, ethyl cellosolve, propyl cellosolve, butyl cellosolve, methyl carpitol, or Particularly representative are ether alcohols such as ethyl carpitol; ketones such as methyl ethyl ketone or diisobutyl ketone; or aromatic hydrocarbons such as toluene.

The solid content acid value of the copolymerization reaction product of the fluororesin (A) and the polymerizable hexamer (B) is suitably within the range of 20 to 150, preferably within the range of 30 to 80.

If the solid content acid value of the copolymerization reaction product is less than 20,
If it exceeds 150, water resistance inevitably tends to decrease, which is not preferable.

Furthermore, among the acid values of the reactant, the acid value based on the reactive unsaturated double bond-containing acid anhydride (a-3) is at least 10, preferably at least 15. is necessary.

If the acid value based on the acid anhydride (a-3) is less than 10, it becomes difficult to make the reactant solubilized in water.

Furthermore, among the acid values of the reactant, the acid value based on the acid group-containing vinyl monomer must also be at least 10, preferably at least 15.

Even when the acid value based on the vinyl monomer is less than 10 i, the reactant is made water-solubilized to 1 in the same manner.

Thus, the aqueous fluororesin composition of the present invention can be obtained by adding a basic compound in an amount such that the pH becomes 6.5 or more to the copolymerization reaction product obtained as described above, and then dissolving the reaction product in an aqueous medium. Obtained by dissolving it in

The basic compound used here is preferably ammonia or a volatile amine. Inorganic bases are not preferred because they tend to remain in the coating film and impair water resistance.

Typical examples of the above amines include alkyl amines such as trimethylamine, triethylamine, or butylamine; alcohol amines such as dimethylaminoethanol, diethanolamine, or methylpropanol; or morpholine. etc.

Additionally, polyvalent amines such as ethylenediamine and diethylenetriamine can also be used.

In the present invention, the aqueous medium means water alone or a mixture with a hydrophilic organic solvent, in which at least 10% by weight is water. Examples of hydrophilic organic solvents include methanol,
Ethanol, n-propertool, isopropertool, n
- alkyl alcohols such as butanol, 5eC-butanol, tert-butanol or isobutanol; glycol ethers such as methyl cellosolve, ethyl cellosolve, propyl cellosolve, butyl cellosolve, hexyl cellosolve, methyl calpitol or ethyl carpitol; or methyl cellosolve acetate Alternatively, glycol ether esters such as ethyl cellosolve acetate-1, dioxane, dimethylformamide, diaseptone alcohol, and tetrahydrofuran can also be used.

The aqueous fluororesin composition of the present invention has very good storage stability. Furthermore, if it is necessary to actively reduce the amount of organic solvents contained, use a so-called low boiling point solvent such as acetone or methyl ethyl ketone, or a solvent that easily azeotropes with water such as butanol or butyl cellosolve for the reaction. By first dissolving the above-mentioned copolymerization reaction product in an aqueous medium using it as a solvent or a dissolving solvent, it can be stably and easily dissolved by distilling it at normal pressure or reduced pressure. , the desired aqueous fluororesin composition with a low organic solvent content is obtained.

The aqueous fluororesin composition of the present invention thus obtained can be used in a wide range of applications, including not only paints, but also water-based inks, adhesives, sealants, and the like.

Depending on each application, the composition of the present invention may further contain a solvent to improve paintability, a tackifier to improve adhesion, a surfactant, and an antifoaming agent, as necessary. It is also possible to add Furthermore, it is also possible to add an amino resin, phenol resin, blocked isocyanate, etc. to the aqueous fluororesin composition of the present invention as a curing agent.

The aqueous fluororesin composition of the present invention can be used as it is as a clear coating, but it can also be used as a coating containing pigments and the like. When turning into paint, ball mill,
Various equipment commonly used for making paints can be used, such as a paint shaker, sand mill, jet mill, triple roll, and kneader. At this time, pigments, dispersion stabilizers, viscosity modifiers, leveling agents, anti-gelling agents, ultraviolet absorbers, etc. can also be added.

As the coating method, conventionally known methods such as roll coating, electrodeposition coating, foot:l-':l-ting, spray painting, and brush painting are used.

The aqueous fluororesin composition of the present invention can be used in a wide variety of applications, from drying at room temperature or forced drying to baking coating using a curing agent such as melamine or blocked isocyanate.
It is preferable to use the baking condition at 0 to 250°C for 10 seconds to 30 minutes.

The aqueous fluororesin composition of the present invention has excellent workability, excellent surface hardness and gloss, and is also flexible, and can form coating films with excellent solvent resistance, stain resistance, and weather resistance. , which can be applied under mild conditions, is useful not only as a baking paint for colored steel plates, color aluminum, aluminum shavings, etc., but also as an air-drying paint that can be applied on-site. The material of the base material is not limited to metals such as iron, aluminum, aluminum, or alloys thereof, such as stainless steel and brass, but also inorganic materials such as glass, cement, and concrete, as well as FRP, polyethylene, polypropylene, and ethylene. It is also useful for coating various organic materials such as plastics such as vinyl acetate copolymers, nylon, acrylic resins, polyesters, ethylene-polyvinyl alcohol copolymers, polyvinyl chloride, polyvinylidene chloride or polycarbonate, or wood. It is particularly useful as a top coat for coated objects that have another base coat. They are also useful in certain applications such as aluminum boules, exterior colored glass and cement tiles.

〔Effect of the invention〕

The aqueous fluororesin composition of the present invention obtained as described above has particularly excellent storage stability, good chroma and transparency, and excellent adhesion to substrates. It is capable of providing a film with weather resistance.

In particular, when used as a paint, it has excellent workability, high surface hardness and gloss, and is also flexible, solvent resistant, stain resistant, and weather resistant. The membrane can be applied under mild conditions.

〔Example〕

Next, the present invention will be explained by reference examples, examples, and comparative examples.
The layer will be explained in detail. In the following, all parts and percentages are based on weight unless otherwise specified.

Reference Example 1 [Example of preparation of fluorine-containing resin (A) having both an acid group and a reactive unsaturated double bond in one molecule] "Fluonate X-700J 200
4 parts methacrylic anhydride 10 parts methacrylic anhydride 0.5 parts methacrylic anhydride (in the above composition,
"1700 J of fluoronate is a fluororesin containing hydroxyl groups made by the above company, with a non-volatile content of 50% and a solid hydroxyl group of 48.) In a Yotsuro flask purged with nitrogen gas, the above composition is added. The target resin (A) was obtained by charging various raw materials, heating the contents to 80°C without stirring, and stirring at the same temperature for 2 hours.

Hereinafter, this will be referred to as resin (A-1).

Reference Example 2 (Same as above) Target resin (A) was obtained in the same manner as Reference Example 1 except that 15 parts of succinic anhydride was used instead of phthalic anhydride. Hereinafter, this will be abbreviated as resin (A-, 2).

Reference Example 3 (same as above) "The same amount of hydroxyl group-containing fluororesin with 200 hydroxyl groups was used instead of 700 J of fluorate, and the amount of methacrylic anhydride used was changed to 2 parts. A target resin (A) was obtained in the same manner as in Reference Example 1.

Hereinafter, this will be referred to as resin (A-2).

Reference Example 4 (Example of Preparation of Control Fluororesin) A control sample containing reactive unsaturated double bonds was prepared in the same manner as Reference Example 1, except that methacrylic anhydride was not used at all. A fluorine-containing resin was obtained. Hereinafter, this resin (A'
−1).

Example 1 Resin (A-1) 214.5 parts Isopropanol 117 Methacrylic acid 7 parts N-Butyl methacrylate 32''"Barbutyl○" [NOF 2... t-Butyl peroxy manufactured by Nippon Oil & Fats Co., Ltd. 2-Ethylhexanony 1 (radical polymerization initiator)] After uniformly mixing the raw materials having the above composition, 100 parts of the mixed solution was charged into a Yotsuro flask purged with nitrogen gas, The remaining mixture was added dropwise over 4 hours while heating to 80°C and maintained at the same temperature, and the acid as a copolymerization reactant was further maintained at the same temperature for 4 hours to continue the reaction. A group-containing modified copolymer was obtained.

Next, 15 parts of triethylamine was added to the reaction solution containing the copolymerization reaction product obtained in the so-called first step and mixed uniformly, and then 150 parts of ion-exchanged water was added dropwise over 30 minutes. An aqueous solution having a solid content of 28.7% and a pH of 9.7 was obtained.

After finishing, this water was further condensed under reduced pressure to obtain the desired aqueous fluororesin composition. The properties of this composition are shown in Table 1.

Example 2 The same amount of resin (A-2) was used instead of resin (A-1), the amount of methacrylic acid used was 8 parts, the amount of n-butyl methacrylate was 28 parts, and a new The desired aqueous fluororesin composition was obtained in the same manner as in Example 1, except that 20 parts of methyl methacrylate was used. The properties of this composition are shown in Table 1.

Example 3 The same amount of resin (A-2) was used instead of resin (A-1), and 15 parts of methyl methacrylate and 10 parts of aphryl n-butyl were used, respectively, instead of 1ln-butyl methacrylate. The desired aqueous fluororesin composition was obtained in the same manner as in Example 1, except that butyl was used and the amount of methacrylic acid used was changed to 4 parts. The properties of this composition are shown in Table 1.

Comparative Example 1 Example 1 except that the same amount of resin (A'1) was used instead of resin (A-1) and the amount of methacrylic acid used was changed to 11 parts. Similarly,
A control aqueous fluororesin composition was obtained. The properties of this composition are as shown in Table 1, but the stability was extremely poor, so the characteristic values could not be determined.

(In Table 1, - indicates unmeasurable.

The evaluation of the dispersion state, stability, and film thickness was ◎ (extremely good), ◯ (good), △ (poor), × (poor), and XX (extremely poor). ) The present invention was originally intended to be a substitute for solvent-based fluororesins, which has the same adhesion to substrates and weather resistance and water resistance of coating films as conventional solvent-based fluororesins. The basic objective of the present invention is to provide a water-based fluororesin composition containing a water-soluble fluororesin as a film-forming component that is completely free from environmental pollution. It is an object of the present invention to provide a highly useful water-based fluororesin that is comparable to fluororesins.

Therefore, the water-based fluororesin composition obtained in Example 1 and the solvent-based fluororesin "Fluonate 701 J
(Previous company product) We will present the results of a comparative study of the coating film performance.

Test conditions PWC = 3% black paint (rMA-100J manufactured by Mitsubishi Kakai Co., Ltd. is used as carbon.) Hardening agent: "Burnock B7-887 J (Dainippon Ink and Chemicals Co., Ltd.)
Co., Ltd.) Mixture: +hco10H=1/1 (equivalent ratio) Base material Zinc diphosphate treated steel plate (Bonde #144 treated dull m plate) Table 2 The measurement methods for the measurement items in Table 2 are as follows.

Gloss: 60°Gloss Hardness: Mitsubishi Pencil Uni, scratch hardness of paint film Adhesion: Rough grain - cellophane tape peeling Water resistance: After immersing in water for 20 days, visually determine the whitening state of the painted surface Weather resistance: rQUV Weather Meter" (manufactured by Suga Test Instruments Co., Ltd.) for 500 hours, visually inspect the paint surface for loss of gloss, crank, etc., and make a comprehensive judgment. Display guidelines: ◎ (no abnormality), ○ ( Good), △ (poor), × (poor) Table 1 shows that the aqueous fluororesin composition of the present invention is in a good solution state as an aqueous solution, and also has an excellent film appearance. It can be seen that
From Table 2, it can be seen that the composition of the present invention has performance equivalent to that of the solvent-based fluororesin, is not inferior in any way, and is good.

teenager Reason Man

Claims (1)

[Claims] 1. Copolymerization of a fluororesin (A) having both an acid group and a reactive unsaturated double bond in one molecule and a monomer (B) containing an acid group-containing vinyl monomer An aqueous fluororesin composition characterized in that a reactant is dissolved in an aqueous medium. 2. Hydroxyl group-containing fluororesin (a-1), reactive unsaturated double bond-containing acid anhydride (a-2), and reactive unsaturated double bond-free acid anhydride (a-3) A copolymerization reaction product of a fluororesin (A) having both an acid group and a reactive double bond in one molecule obtained by reacting the above with a monomer (B) containing an acid group-containing vinyl monomer. , an aqueous fluororesin composition characterized in that it is dissolved in an aqueous medium. 3. 90 to 98% by weight of the hydroxyl group-containing fluororesin (a-1), 0.1 to 2% by weight of the reactive unsaturated double bond-containing acid anhydride (a-2), and the reactive unsaturated double bond-containing acid anhydride (a-2). An acid group and a reactive unsaturated compound in one molecule obtained by reacting 2 to 10% by weight of an acid anhydride (a-3) that does not contain a heavy bond in a total amount of 100% by weight. A copolymerization reaction product of 40 to 95 parts by weight of a fluororesin (A) having double bonds and 60 to 5 parts by weight of a monomer (B) containing an acid group-containing vinyl monomer is added to an aqueous medium. An aqueous fluororesin composition characterized by being melted. 4. The above-described fluororesin (A) having both an acid group and a reactive unsaturated double bond in one molecule is anhydrous as the reactive unsaturated double bond-containing fluororesin (a-2). The aqueous fluororesin composition according to claim 1, which is obtained using acrylic acid and/or methicrylic anhydride. 5. The fluororesin (A) having both an acid group and a reactive unsaturated double bond in one molecule has a hydroxyl value of 10 to 200, the hydroxyl group-containing fluororesin (a-1)
The aqueous fluororesin composition according to any one of claims 1 to 4, which is obtained using. 6. The above-mentioned fluororesin (A) having both an acid group and a reactive unsaturated double bond in one molecule is obtained using the above-mentioned copolymerization reaction product having an acid value of 20 to 150. The aqueous fluororesin composition according to any one of claims 1 to 4. 7. The fluororesin (A) having both an acid group and a reactive unsaturated double bond in one molecule is converted into the acid anhydride (a-3) which does not contain a reactive unsaturated double bond. The aqueous fluororesin composition according to any one of claims 1 to 6, which is obtained using the copolymerization reaction product having a basic acid value of at least 10. 8. The copolymer in which the fluororesin (A) having both an acid group and a reactive unsaturated double bond in one molecule has an acid value of at least 10 based on the acid group-containing vinyl monomer. Claims 1 to 1, which are obtained using reactants.
6. The aqueous fluororesin composition according to any one of 6.