JP2955336B2 - Aqueous dispersion - Google Patents

Description

The present invention relates to aqueous dispersions.

[Prior art] Conventionally, a copolymer comprising a fluoroolefin, cyclohexyl vinyl ether and other various monomers is soluble in an organic solvent at room temperature, and when used as a paint, is transparent and has high gloss. It is known that a coating film having excellent characteristics such as high weather resistance, water repellency, oil repellency, stain resistance, and non-adhesiveness is provided.
44083), and its use is increasing in fields such as architecture.

On the other hand, since the use of hydrophilic organic solvents is being regulated in recent years from the viewpoint of air pollution, the demand for water-based paints and powder paints that do not use hydrophilic organic solvents is increasing. However, it has been reported that those having no functional group can be produced by emulsion polymerization (JP-A-55-2541).
1).

Emulsion polymerization of a fluorine-containing copolymer having a hydroxyl group is described in JP-A-57-34107 and JP-A-61-231044. However, in these methods, it was essential to use an emulsifier and a hydrophilic organic solvent in combination. In these methods, when one or both of the emulsifier and the hydrophilic organic solvent are not used, an aqueous dispersion is not obtained, and even if an aqueous dispersion is obtained, the mechanical and chemical stability is extremely high. The aqueous dispersions obtained by these methods have poor film-forming properties, and the appearance of the resulting coating film may be inferior to that of the solvent-based paint. Also in the case of dispersing the pigment, when the pigment concentration is increased, the gloss decreases, and when a paint having a high pigment concentration is required, a high gloss coating film cannot be obtained.

[Problems to be solved by the invention] The present invention is to solve the above-mentioned problems of the related art. That is, an object of the present invention is to provide an aqueous dispersion which has excellent film-forming properties, improves the appearance of a coating film, and enables production of a coating composition having a high pigment concentration.

[Means for Solving the Problems] The present invention has been made to solve the above-mentioned problems, and comprises (a) a polymerized unit based on a fluoroolefin and (b) a macromonomer having a hydrophilic site (hereinafter, referred to as a macromonomer). An aqueous dispersion in which a water-soluble resin is blended with an aqueous dispersion in which a fluorinated copolymer having a polymerized unit based on a hydrophilic macromonomer) as an essential component is dispersed in water.

In the present invention, as the fluoroolefin, a fluoroolefin having about 2 to 4 carbon atoms such as vinylidene fluoride, trifluoroethylene, chlorotrifluoroethylene, tetrafluoroethylene, pentafluoropropylene, and hexafluoropropylene is preferably employed. Particularly, a perhaloolefin is preferable.

In the aqueous dispersion of the present invention, the fluorinated copolymer is (b)
It is important to have polymerized units based on hydrophilic macromonomers. Since this unit (b) is contained as an essential component of the fluorinated copolymer, the mechanical and chemical stability of the aqueous dispersion is improved, and the film-forming properties and the water resistance of the coating film are also improved. improves.

The hydrophilic portion of the hydrophilic macromonomer in the present invention indicates a portion having a hydrophilic group, a portion having a hydrophilic bond, and a portion composed of a combination thereof. This hydrophilic group may be any of ionic, non-ionic, amphoteric and combinations thereof, but when the hydrophilic site consists only of a site having an ionic hydrophilic group, the aqueous dispersion Is not preferable because of the problem of chemical stability of the compound, and it is desirable to combine with a site having a nonionic or amphoteric hydrophilic group or a site having a hydrophilic bond.

The macromonomer refers to a low molecular weight polymer or oligomer having a radical polymerizable unsaturated group at one terminal. That is, it is a compound having a radical polymerizable unsaturated group at one terminal and having two or more repeating units. Depending on the type of repeating unit, it is usually
Those having 100 or less are preferably employed from the viewpoint of polymerizability, water resistance and the like.

Specific examples of the hydrophilic macromonomer include polyethers having a radically polymerizable unsaturated group at one terminal, such as the following.

CH ₂ = CHO (CH ₂ ) _p [O (CH ₂ ) _m ] _n OX Formula 1 (p is an integer of 1 to 10, m is an integer of 1 to 4, n is an integer of 2 to 20, X Is a hydrogen atom or a lower alkyl group.) CH ₂ CHCHCH ₂ O (CH ₂ ) _p [O (CH ₂ ) _m ] _n OX Formula 2 (p, m, n and X are the same as those of Formula 1) CH ₂ = CHO (CH ₂ ) _p (OCH ₂ CH ₂ ) _m −− (OCH ₂ CH (CH ₃ )) _n OX Formula 3 (p is an integer of 1 to 10, m is 2 An integer of from 0 to 20, n is an integer of from 0 to 20, X is a hydrogen atom or a lower alkyl group, and the oxyethylene unit and the oxypropylene unit may be arranged in any form of block or random.) CH ₂ = CHCH ₂ O (CH ₂ ) _p (OCH ₂ CH ₂ ) _m − − (OCH ₂ CH (CH ₃ )) _n OX formula 4 (p, m, n, and X are the same as those in formula 3) , Oxyethylene and oxypropylene units are blocks, runs CH ₂ CHOCHO (CH ₂ ) _n O (CO (CH ₂ ) _m O) _p H (5) where n is an integer of 1 to 10 and m is (Integer of 1 to 10, p is an integer of 1 to 30) Among them, those having a vinyl ether structure at one end are preferably employed because of their excellent copolymerizability with fluoroolefins. In particular, a polyether chain portion composed of an oxyethylene unit or an oxyethylene unit and an oxypropylene unit is preferable because of its excellent hydrophilicity and the like. Unless it has two or more oxyethylene units, various properties such as stability cannot be achieved. If the number of oxyalkylene units is too large, the water resistance and weather resistance of the coating film are deteriorated, which is not preferable.

Such a hydrophilic macromonomer is a vinyl ether or an allyl ether having a hydroxyl group, formaldehyde,
It can be produced by a method such as polymerizing a diol or subjecting a compound having an alkylene oxide or lactone ring to ring-opening polymerization.

The hydrophilic macromonomer may be a macromonomer having a radically polymerized chain of a hydrophilic ethylenically unsaturated monomer and having a radically polymerizable unsaturated group such as vinyl ether or allyl ether at a terminal.

Such a macromonomer is described by Yamashita et al. In Polym. Bull.,
5,335 (1981). That is, by subjecting an ethylenically unsaturated monomer having a hydrophilic group to radical polymerization in the presence of an initiator having a condensable functional group and a chain transfer agent, a polymer having a condensable functional group is produced. A method of reacting a compound such as glycidyl vinyl ether or glycidyl allyl ether with a functional group of the polymer to introduce a radical polymerizable unsaturated group into a terminal is exemplified.

The ethylenically unsaturated monomers used in the production of this macromonomer include (meth) acrylamide, N-
Methylol (meth) acrylamide, 2-methoxyethyl (meth) acrylate, diacetone acrylamide,
Examples include hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, (meth) acrylate of polyhydric alcohol, and vinylpyrrolidone.

Other than the above, copolymerizable monomers include (meth)
There are acrylamide and its derivatives, N-methylol acrylamide derivatives, ethyl carbitol acrylate, triethylene glycol methyl ether acrylate, (2-hydroxyethylacrylic acid) phosphate, butoxyethyl acrylate, and the like.

In addition, as an initiator used in the production of this macromonomer, 4,4′-azobis-4-cyanovaleric acid, 2,2′-azobis-2-amidinopropane hydrochloride,
Potassium peroxide, ammonium peroxide, azobisisobutyronitrile, benzoyl peroxide, and the like.

The fluorine-containing copolymer in the present invention may contain (c) a polymerized unit having a hydroxyl group, an epoxy group or a glycidyl group, in addition to the above two units. The stability of the aqueous dispersion of the present invention is not impaired even if the fluorine-containing copolymer has a hydroxyl group. Further, the fluorine-containing copolymer is a hydroxyl group,
When it has an epoxy group or a glycidyl group, there is an advantage that when used as a paint base, a coating film having extremely excellent water resistance and solvent resistance can be obtained by using a curing agent in combination.

In (c), the method of forming a polymerized unit having a hydroxyl group includes a method of copolymerizing a hydroxyl group-containing monomer, a method of polymerizing a polymer to form a unit having a hydroxyl group, and the like. is there.

Here, examples of the hydroxyl group-containing monomer include hydroxyalkyl vinyl ethers such as hydroxybutyl vinyl ether, hydroxyalkyl allyl ethers such as hydroxyethyl allyl ether, and hydroxyalkyl esters of (meth) acrylic acid such as hydroxyethyl (meth) acrylate. And hydroxyalkyl vinyl esters and hydroxyalkyl allyl esters.

Examples of the method of forming a unit having a hydroxyl group by polymerizing a polymer include a method of copolymerizing a hydrolyzable vinyl ester after polymerization, and then hydrolyzing to form a hydroxyl group. Is done.

The fluorine-containing copolymer in the present invention may contain a unit based on a monomer copolymerizable therewith, in addition to the above units.

Examples of such monomers include olefins such as ethylene and propylene, vinyl ethers such as ethyl vinyl ether, propyl vinyl ether, butyl vinyl ether and cyclohexyl vinyl ether, vinyl esters such as vinyl butanoate and vinyl octanoate, styrene and vinyl. Examples include vinyl compounds such as aromatic vinyl compounds such as toluene, allyl compounds such as ethyl allyl ether, acryloyl compounds such as butyl acrylate, and methacryloyl compounds such as ethyl methacrylate. In particular, olefins, vinyl ethers, vinyl esters, allyl ethers,
Allyl esters are preferably employed.

Here, the olefins preferably have about 2 to 10 carbon atoms, and the vinyl ethers, vinyl esters, allyl ethers and allyl esters have 2 carbon atoms.
Those having about 15 to 15 linear, branched or alicyclic alkyl groups are preferred. In such a monomer, at least a part of hydrogen bonded to carbon may be replaced by fluorine.

In the present invention, the fluorine-containing copolymer has (a) a polymerized unit based on a fluoroolefin in an amount of 20 to 80 mol%,
(B) The polymerized unit based on the hydrophilic macromonomer is 0.
It is preferred that the ratio be 1 to 25 mol%.

If the amount of the polymerized unit based on the fluoroolefin is too small, the weather resistance will not be sufficiently exhibited, and if it is too large, the water dispersibility will be extremely poor, which is not preferable. Especially 30 ~
Preferably it is 70 mol%.

On the other hand, if the amount of the polymerized unit based on the hydrophilic macromonomer is too small, the water dispersibility becomes extremely poor, and if the amount is too large, the weather resistance and water resistance of the coating film become poor. In particular, in order to achieve an extremely excellent effect on film forming properties, it is preferable that this unit is contained in a ratio of 0.3 to 20 mol%.

When a polymerized unit having a hydroxyl group is contained, it is preferably at most 25 mol%. If the proportion of this unit is too large, the water dispersibility decreases, and when the coating film is cured, it becomes hard and brittle, and the water resistance may decrease due to the residual hydroxyl groups, which is not preferable.
In the case where the above-mentioned unit (b), that is, the polymerized unit based on the hydrophilic macromonomer contains a unit having a hydroxyl group, the preferred amount of the polymerized unit having a hydroxyl group is (b) the hydrophilic macromonomer. Means the total amount of the polymerized unit and the polymerized unit having a hydroxyl group.

The unit other than the polymerized unit based on the fluoroolefin and the polymerized unit based on the hydrophilic macromonomer is preferably 0 to 70 mol%. If this unit is too large, the weather resistance will be poor, which is not preferable.

The aqueous dispersion of the present invention is obtained by dispersing the above fluorinated copolymer in water. Further, the aqueous dispersion of the present invention,
Even without the presence of an emulsifier or hydrophilic organic solvent usually used in a fluoropolymer aqueous dispersion, it exhibits excellent mechanical and chemical stability, but one or both of the emulsifier and the hydrophilic organic solvent may be used. It may be added. However, it is preferable that the hydrophilic organic solvent is not added because there is a solvent regulation.

Here, when using an emulsifier, anionic, cationic, nonionic, amphoteric, nonionic-cationic,
Alternatively, a nonionic-anionic emulsifier or an emulsifier having a reactive group can be used alone or in combination. When a hydrophilic organic solvent is used, the content is preferably 20% by weight or less from the viewpoint of safety.

The aqueous dispersion of the present invention can be produced by emulsion polymerization of a fluoroolefin, a hydrophilic macromonomer, and, if necessary, another monomer in an aqueous medium. The initiation of emulsion polymerization is carried out by the addition of a polymerization initiator in the same manner as the usual initiation of emulsion polymerization.

As such a polymerization initiator, a usual radical initiator can be used, but a water-soluble initiator is preferably employed, and specifically, a persulfate such as ammonium persulfate, hydrogen peroxide or a mixture thereof with sodium hydrogen sulfite, A redox initiator comprising a combination with a reducing agent such as sodium sulfate, and an inorganic initiator in which a small amount of iron, ferrous salt, silver sulfate, and the like coexist, or disuccinic peroxide, diglutaric peroxide, and the like. And organic initiators such as dibasic acid peroxide, azobisisobutylamidine dihydrochloride, and azobisbutyronitrile.

The amount of the polymerization initiator used can be appropriately changed depending on the type, emulsion polymerization conditions, and the like.
About 0.005 to 0.5 parts by weight per 100 parts by weight is preferably employed. Further, these polymerization initiators may be added all at once, or may be added in portions as needed.

Further, a pH adjuster may be used for the purpose of increasing the pH of the emulsion. Examples of such a pH adjuster include inorganic salts such as sodium carbonate, potassium carbonate, sodium o-hydrogen phosphate, sodium thiosulfate, and sodium tetraborate; and organic bases such as triethylamine, triethanolamine, dimethylethanolamine, and diethylethanolamine. And the like. The amount of the pH adjuster is usually about 0.05 to 2 parts by weight per 100 parts by weight of the emulsion polymerization medium, preferably
It is about 0.1 to 2 parts by weight. A higher pH tends to increase the polymerization rate.

The optimum value of the emulsion polymerization initiation temperature is appropriately selected mainly depending on the type of the polymerization initiator, but is usually preferably 0 to 100 ° C, particularly preferably about 10 to 90 ° C. The reaction pressure can be appropriately selected, but is usually 1 to 100 kg / cm ² , especially 2
About 50 kg / cm ² is preferably adopted.

In such a production method, an additive such as a monomer, a solvent, and an initiator may be charged as it is and polymerized as it is. However, by decreasing the particle size of the dispersed particles, various properties such as stability of the dispersion and gloss of the coating film can be obtained. For the purpose of improving the physical properties, pre-emulsification using a stirrer such as a homogenizer before adding a polymerization initiator,
Thereafter, an initiator may be added for polymerization. Further, the monomers may be added in portions or continuously, and in that case, the monomer compositions may be different.

As the water-soluble resin, a fluorinated copolymer having a carboxyl group is suitably employed. The fluorine-containing polymer having a carboxyl group in the present invention is disclosed in
58-136605, that is, by reacting a dibasic acid anhydride on a fluorine-containing polymer having a hydroxyl group,
A fluoropolymer having a carboxyl group obtained by a method of introducing a carboxyl group, a fluoropolymer in which a carboxyl group is generated by hydrolyzing an ester bond in the polymer, and the like are used.

Specifically, fluoropolymers containing units based on hydroxyl group-containing monomers such as hydroxyalkyl vinyl ether, hydroxyalkyl (meth) acrylate, and allyl alcohol by addition copolymerization or grafting, vinyl carboxylate, A fluorinated polymer in which a unit based on a monomer having a group that can be converted to a hydroxyl group by hydrolysis such as allyl acid or alcoholysis is similarly contained, wherein the site is converted to a hydroxyl group, Various compounds represented by the formula 6 (where R represents two organic groups) are added to a fluorine-containing polymer having a hydroxyl group such as a condensation polymerization type obtained by a reaction between a polyol and epichlorohydrin. , Specifically, succinic anhydride, glutaric anhydride, itaconic anhydride, adipic anhydride, cyclohexa 1,2-dicarboxylic anhydride, c
is-4-cyclohexene-1,2-dicarboxylic anhydride,
Phthalic anhydride, 1,8-naphthalic anhydride, a dibasic acid anhydride such as maleic anhydride is reacted to convert at least a part of the hydroxyl group to an ester group represented by the formula 7,
By introducing a carboxyl group, a fluoropolymer having a carboxyl group can be obtained.

Further, a fluoropolymer having a carboxyl group can be obtained by hydrolyzing a fluoropolymer obtained by copolymerizing a monomer that generates a carboxyl group by hydrolysis of a vinyl ester compound, an allyl ester compound, or the like. .

In addition, the fluoropolymer having a carboxyl group contains 20 to 80 mol% of a polymerized unit based on a fluoroolefin.
Those containing are preferably employed. Copolymers of fluoroalkyl esters of (meth) acrylic acid produce excellent effects, such as oil repellency, but are fluoropolymers obtained by copolymerizing fluoroolefins from the viewpoint of weather resistance, that is, when the carbon atoms of the main chain are used. This is not preferable because it is slightly worse than a polymer having a directly bonded fluorine atom. On the other hand, when the ratio of the polymerized units based on the fluoroolefin is smaller than the above ratio, the weather resistance is not sufficiently exhibited as a weather resistant coating, which is not preferable. On the other hand, if the ratio is higher than the above ratio, it is not preferable because it becomes difficult to make the compound water-soluble or water-dispersible. Polymerized units based on special fluoroolefins
A fluorine-containing polymer in an amount of 30 to 70 mol% is preferably employed.

Here, examples of the fluoroolefin include the following.

CClF = CF ₂ , CHCl = CF ₂ , CCl ₂ = CF ₂ , CClF = CCIF, CHF
_{= CCl 2, CH 2 = CClF} , fluoroethylene such as CCl ₂ = CClF.

CF ₂ ClCF = CF ₂ , CF ₃ CCl = CF ₂ , CF ₃ CF = CFCl, CF ₂ ClCCl
= CF ₂ , CF ₂ ClCF = CFCl, CFCl ₂ CF = CF ₂ , CF ₃ CCl = CClF,
CF ₃ CCl = CCl ₂ , CF ₂ ClCF = CCl ₂ , CF ₂ ClCCl = CCl ₂ , CFCl ₂
CCl = CCl ₂ , CF ₃ CF = CHCl, CF ₂ ClCF = CHCl, CHF ₂ CCl = CC
fluoropropylene such as l ₂ , CF ₂ ClCH = CCl ₂ , CF ₂ ClCCl = CHCl;

_{CF 3 CCl = CFCF 3, CF} 2 = CFCF 2 CClF 2, CF 3 CF 2 CF = carbon number of _2, such as CCl 4 or more fluoroolefins.

Further, as a monomer to be introduced a carboxyl group,
Hydroxyl-containing monomers capable of introducing a carboxyl group by the action of a dibasic acid anhydride as described above, that is, hydroxyalkyl vinyl ether, hydroxyalkyl allyl ether, vinyl alcohol, allyl alcohol, hydroxyalkyl (meth) acrylate, and the like. No. Of these, hydroxyalkyl vinyl ether and hydroxyalkyl allyl ether are preferably employed from the viewpoint of copolymerizability with the above-mentioned fluoroolefin.

Further, from the viewpoint of reactivity with a dibasic acid anhydride, those containing a hydroxyl group in a primary or secondary form are preferably employed. In particular, CH ₂ CHCH (CH ₂ ) _m O (CH ₂ ) _n OH (m is 0 or 1,
(n is an integer of 2 to 6) hydroxyalkyl vinyl ether or hydroxyalkyl allyl ether is preferably employed.

Further, the reaction for converting the hydroxyl group of the fluoropolymer into a carboxyl group may be performed for a part of the hydroxyl groups or may be performed for all of the hydroxyl groups. However, it is preferable that the acid value of the fluoropolymer having a carboxyl group be 5 mgKOH / g or more. If the amount of the carboxyl group is too small, that is, if the acid value is less than 5 mgKOH / g, it is difficult to form an aqueous solution, which is not preferable. If the acid value is too large, the alkali resistance, boiling water resistance, etc. of the coating film may decrease, which is not preferable. Acid value is 5-150mgKOH
/ g, preferably about 5 to 100 mgKOH / g of a fluoropolymer.

In addition, it is preferable that at least a part of the above-mentioned hydroxyl groups remain because a reaction with a curing agent and a coating film having excellent solvent resistance and the like can be obtained. Especially the hydroxyl value is 10 ~ 150m
Those having a ratio of about gKOH / g are preferred. Further, the fluoropolymer having a carboxyl group may be composed of only a polymerized unit based on a fluoroolefin as described above, a polymerized unit having a carboxyl group, and a polymerized unit having a hydroxyl group. A copolymerizable monomer may be copolymerized.

Depending on the desired film properties (hardness, gloss, pigment dispersibility, water resistance, etc.), alkyl vinyl ether, alkyl allyl ether, alkanoic acid vinyl ester, alkanoic acid allyl ester, fluoroalkyl vinyl ether, glycidyl vinyl ether, etc. are appropriately copolymerized. You may. Even when these monomers are copolymerized, the content ratio of polymerized units based on fluoroolefin, acid value,
The hydroxyl value is preferably within the above range.

In the present invention, it is preferable that at least a part of the carboxyl group of the fluoropolymer having a carboxyl group is neutralized by a basic compound. Examples of such a basic compound include the following.

Ammonia, monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine,
Primary to tertiary alkylamines such as triethylamine, monoisopropylamine, diisopropylamine, triisopropylamine, monobutylamines, dibutylamines, and tributylamines. Alkanolamines such as monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine, dimethylaminoethanol and diethylaminoethanol. Alkylene polyamines such as ethylene diamine, propylene diamine, diethylene triamine and triethylene tetramine. Alkyleneimines such as propyleneimine and the like. Piperazine, morpholine, pyrazine, pyridine and the like.

As the water-soluble resin, generally known water-soluble acrylic resins and water-soluble polyester resins can also be used.

The aqueous dispersion of the present invention can be used as an aqueous paint as it is, but if necessary, a colorant, a plasticizer, an ultraviolet absorber, a leveling agent, an anti-cissing agent, an anti-burr agent, a curing agent, etc. Is also good.

Examples of the coloring agent include dyes, organic pigments, and inorganic pigments. Examples of the plasticizer include conventionally known plasticizers, for example, low molecular weight plasticizers such as dimethyl phthalate and dioctyl phthalate, and high molecular weight plasticizers such as a vinyl polymer plasticizer and a polyester plasticizer. Examples of the curing agent include block isocyanates such as hexamethylene diisocyanate trimer, melamine resins such as methylated melamine, methylolated melamine and butylolated melamine, and urea resins such as methylated urea and butylated urea. Further, a pH adjuster may be added to improve the stability of the aqueous dispersion.

When the aqueous dispersion of the present invention is used as an aqueous paint base, it may be used as it is, but may be blended with another aqueous dispersion such as an acrylate polymer or an aqueous dispersion of the present invention having a different composition. In some cases, the physical properties such as gloss, antifouling property, hardness, and adhesiveness of the coating film and the dispersibility of the pigment are improved, or the cost may be more advantageous. When adding a pigment, it is preferable to add 5 parts by weight or more.

[Examples] Hereinafter, the present invention will be described specifically with reference to Synthesis Examples (Examples 1 to 8), Comparative Examples (Example 9), and Examples (Examples 10 to 15), but the present invention is not limited thereto. . Parts in each example indicate parts by weight. Table 1 shows the structure and number average molecular weight _Mn of each hydrophilic macromonomer used in the synthesis examples. Table 2 shows the characteristic values of the aqueous dispersions obtained in Examples 1 to 6.

"Example 1" Ethyl vinyl ether (EVE) 22.1 in a 200 ml stainless steel autoclave with a stirrer (withstand pressure 50 kg / cm ² )
Part, ω-hydroxybutyl vinyl ether (HBVE) 1.5
Parts, hydrophilic macromonomer A4.5 parts, ion-exchanged water 99.1
Parts, ammonium perfluorooctanoate (PFOA) 0.35
Parts, potassium carbonate 0.35 parts, sodium bisulfite 0.02
And 0.11 part of ammonium persulfate, cooled with ice, pressurized with nitrogen gas to 3.5 kg / cm ² and degassed.
After repeated times, the mixture was degassed to 10 mmHg, dissolved air was removed, 38.0 parts of chlorotrifluoroethylene (CTFE) was charged, and the mixture was reacted at 30 ° C. for 12 hours.

"Example 2" 19.5 parts of cyclohexyl vinyl ether (CHVE), 10.2 parts of EVE, hydrophilic macromonomer B in the autoclave
13.6 parts, ion-exchanged water 114.6 parts, PFOA 0.44 parts, potassium carbonate 044 parts, sodium hydrogen sulfite 0.02 parts, ammonium persulfate 0.14 parts were charged and treated in the same manner as in Example 1, and then tetrafluoroethylene (TFE) was 30.9 parts. 30 after charging
The reaction was carried out at 12 ° C. for 12 hours.

"Example 3" 21.7 parts of CHVE, 7.9 parts of EVE, HBVE in the autoclave
6.4 parts, hydrophilic macromonomer A6.9 parts, ion-exchanged water 12
4.7 parts, 0.44 parts of PFOA, 044 parts of potassium carbonate, 0.02 parts of sodium bisulfite, 0.14 parts of ammonium persulfate,
After treating in the same manner as in Example 1, 42.1 parts of CTFE were charged, and
The reaction was performed for 12 hours.

EVE354 parts "Example 4" internal volume 2500ml stainless steel stirrer with an autoclave (pressure-resistant 50kg / cm ^2), HBVE24 parts C55 parts hydrophilic macromonomer, 980 parts of deionized water, PFOA10.4 parts, manufactured by Nippon Emulsifier Co. 13 parts of Newcol 293 emulsifier, also Newcol 2
40 parts 18 parts, potassium carbonate 3.75 parts, ammonium persulfate 0.
Charge 7 parts, cool with ice, pressurize and deaerate nitrogen gas to 3.5 kg / cm ² , repeat this twice, deaerate to 120 mmHg, remove dissolved air, 243 parts of CTFE After charging 3
The reaction was started at 0 ° C.

The autoclave pressure at this time is 3 kg / cm in gauge pressure.
^{At 2} G, the pressure dropped as the reaction proceeded, but an additional 365 parts of CTFE was added so that the pressure remained constant (3 kg / cm ² G). Thereafter, the reaction was performed until the gauge pressure became approximately 0 kg / cm ² G. Total reaction time was 16 hours.

EVE354 parts "Example 5" internal volume 2500ml stainless steel stirrer with an autoclave (pressure-resistant 50kg / cm ^2), HBVE24 parts C55 parts hydrophilic macromonomer, 980 parts of deionized water, PFOA10.4 parts, Nippon Emulsifier Co. emulsifier 13 copies of Newcol 293, also Newcol 240
18 parts of potassium carbonate, 2.1 parts of potassium carbonate and 0.7 parts of ammonium persulfate were charged, cooled with ice, and pressurized and degassed with nitrogen gas to 3.5 kg / cm ² .These steps were repeated twice, followed by degassing to 120 mmHg. After removing the dissolved air, 608 parts of CTFE were charged and 3
The reaction was carried out at 0 ° C. for 5 hours until the gauge pressure became approximately 0 kg / cm ² G.

"Example 6" In an autoclave with a stirrer made of stainless steel having an internal volume of 2500 ml (withstand pressure of 50 kg / cm ² ), 354 parts of EVE, 24 parts of HBVE, 55 parts of hydrophilic macromonomer C, 980 parts of ion-exchanged water, potassium carbonate 2.1
Parts, 0.7 parts of ammonium persulfate, ice-cooled, pressurized and degassed with nitrogen gas to 3.5 kg / cm ² , repeated twice, degassed to 120 mmHg, and removed dissolved air After charging 243 parts of CTFE, the reaction was started at 30 ° C.

The autoclave pressure at this time is 3 kg / cm in gauge pressure.
^{At 2} G, the pressure dropped as the reaction proceeded, but an additional 365 parts of CTFE was added so that the pressure remained constant (3 kg / cm ² G). The reaction was performed for 26 hours in this manner.

[Example 7 (preparing an aqueous dispersion of a water-soluble resin)] In a 200 ml stainless steel autoclave with a stirrer (withstand pressure 50 kg / cm ² ), 35 parts of CTFE, 11 parts of CHVE, 4.3 parts of EVE, HB
After adding 15 parts of VE, 98 parts of xylene, 28 parts of ethanol, 0.5 parts of azobisisobutyronitrile, and 1.5 parts of anhydrous potassium carbonate, cooling with liquid nitrogen, and removing dissolved air by solidification and deaeration, the mixture was heated at 65 ° C. The reaction was carried out for a time to obtain a hydroxyl group-containing fluoropolymer. The intrinsic viscosity of the obtained polymer measured at 30 ° C. in tetrahydrofuran was 0.11 dl / g.

The resulting hydroxyl-containing fluoropolymer (having a hydroxyl value of about 120 m
A solution of about 60% xylene (gKOH / g resin) was heated to 90 ° C., 3.6 parts of succinic anhydride was added to 100 parts of the polymer, and 0.2 part of triethylamine was further added to react for 2 hours.

When the infrared spectrum of the reaction solution was measured, the characteristic absorptions of anhydride (1850 cm ^-1 and 1780 cm ^-1 ) observed before the reaction had disappeared after the reaction, and the carboxylic acid (1710 cm ^-1 ) and ester ( An absorption of 1735 cm ^-1 ) was observed.

The carboxyl group-introduced fluoropolymer had an acid value of 20 mg KOH / g resin and a hydroxyl value of 100 mg KOH / g resin.

The solvent was once evaporated from the obtained fluorine-containing polymer to isolate a solid portion of the polymer, which was then newly dissolved with acetone to obtain an acetone solution of about 60%.

After 135 parts of the above-prepared fluoropolymer solution and 4 parts of triethanolamine were added to a reaction vessel equipped with a stirrer, a thermometer and a reflux condenser, butyl cellosolve 26 was added.
And 150 parts of deionized water to prepare an aqueous solution.

"Example 8 (preparation of pigment dispersion)" 60 parts of titanium oxide pigment CR-90 (manufactured by Ishihara Sangyo Co., Ltd.), 2.9 parts of Disroll H-14N dispersant (manufactured by Nippon Emulsifier Co., Ltd.), FS Antifoam 013B defoamer ( 0.2 parts by Dow Corning)
38 parts of ion-exchanged water and 100 parts of glass beads were mixed and dispersed using a Glenmiffre disperser to prepare a pigment dispersion.

“Example 9” Surfynol D101 was added to 100 parts of the aqueous dispersion prepared in Example 1.
(Defoaming agent manufactured by Nissin Chemical Industry Co., Ltd.) 0.1 part was blended and mixed well with stirring. Further, 10.3 parts of the pigment dispersion prepared in Example 8 was blended, dispersed by a paint shaker for 30 minutes, and filtered through a 200 mesh wire net to obtain a paint. The obtained paint was applied on an aluminum plate and the appearance was measured. The results are shown in Table 3 together with the results of Examples 10 to 15.

"Example 10" 100 parts of the aqueous dispersion prepared in Example 1, 2 parts of the aqueous solution prepared in Example 7, and 0.1 part of Surfynol D101 (an antifoaming agent manufactured by Nissin Chemical Industry Co., Ltd.) were blended and mixed well. Further, 10.3 parts of the pigment dispersion prepared in Example 8 was blended, dispersed for 30 minutes with a paint shaker, and filtered through a 200-mesh wire net to obtain a paint.
The obtained paint was applied on an aluminum plate and the appearance was measured.

"Example 11" 100 parts of the aqueous dispersion prepared in Example 2, 2 parts of the aqueous solution prepared in Example 7, and 0.2 parts of FS Antifoam 013B (Antifoaming agent manufactured by Dow Corning) were blended and thoroughly stirred and mixed. Further, 10.3 parts of the pigment dispersion prepared in Example 8 was mixed and applied in the same manner as in Example 10.

"Example 12" 100 parts of the aqueous dispersion prepared in Example 3, 3.5 parts of the aqueous solution prepared in Example 7, and 0.2 part of FS Antifoam 013B (Antifoaming agent manufactured by Dow Corning) were blended. And applied on an aluminum plate.

"Example 13" 100 parts of the aqueous dispersion prepared in Example 4, 3.5 parts of the aqueous solution prepared in Example 7, 0.2 parts of FS Antifoam 013B (Antifoamer manufactured by Dow Corning), and 10 parts of ion-exchanged water were blended. It was made into a paint in the same manner as in Example 10 and applied on an aluminum plate.

"Example 14" 100 parts of the aqueous dispersion prepared in Example 5, 10 parts of the aqueous solution prepared in Example 7, 0.1 part of Surfynol D101 (antifoaming agent manufactured by Nissin Chemical Co., Ltd.), and 10 parts of ion-exchanged water were mixed. , And applied in the same manner as in Example 10.

"Example 15" 100 parts of the aqueous dispersion prepared in Example 6, 12 parts of the aqueous solution prepared in Example 7, 0.2 part of FS Antifoam 013B (Antifoaming agent manufactured by Dow Corning), and 13 parts of ion-exchanged water were blended. It was applied in the same manner as in Example 10.

[Effects of the Invention] The aqueous dispersion of the present invention is extremely useful as a paint base having excellent gloss and pigment dispersibility, and a coating film obtained from the paint has excellent weather resistance, excellent gloss, and uneven color. Has the advantage of not having.

Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08F 290/06 C08F 290/06 C09D 5/02 C09D 5/02 127/12 127/12 127/22 127/22 155/00 155/00 ( 58) Field surveyed (Int.Cl. ⁶ , DB name) C08L 55/00 C08L 27/12-27/22 C08L 101/14 C08F 290/06 C09D 5/02 C09D 155/00 C09D 127/12-127 / twenty two

Claims (4)

(57) [Claims] 1. An aqueous solution in which a fluorinated copolymer containing (a) a polymerized unit based on a fluoroolefin and (b) a polymerized unit based on a macromonomer having a hydrophilic moiety as essential components is dispersed in water. An aqueous dispersion obtained by blending a water-soluble resin with the dispersion. 2. The aqueous dispersion according to claim 1, wherein the macromonomer having a hydrophilic site is a polyether having a radically polymerizable unsaturated group at one end. 3. The aqueous dispersion according to claim 1, wherein the fluorinated copolymer is a copolymer containing (c) a polymerized unit having a hydroxyl group, an epoxy group or a glycidyl group. 4. The water-soluble resin is a fluoropolymer having a carboxyl group, wherein the water-soluble resin is a water-soluble fluoropolymer obtained by neutralizing at least a part of the carboxyl group with a basic compound. 3. The aqueous dispersion according to 3.