JP3264731B2 - Water- and oil-repellent composition and article coated therewith - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a fluorine-based water / oil repellent composition and an article coated with the composition.

[0002]

2. Description of the Related Art In recent years, water- and oil-repellent processing has been actively carried out, and various water- and oil-repellent compositions have been provided according to purposes.
Among these, with regard to cotton fabrics for clothing, a fluorinated polymer containing a unit based on acrylate or methacrylate having C _n F _{2n + 1} (an integer of 20 ≧ n ≧ 4) as a polyfluoroalkyl group as an active ingredient is known. I have. On the other hand, nozzles for inkjet printers, molds,
It is known to coat a plate or the like with a fluororesin having a fluorinated aliphatic ring structure in the main chain.

[0003]

Fluoropolymer which have a polyfluoroalkyl group [0008] is excellent in water and oil repellency, but film forming property is insufficient, abrasion resistance, is insufficient durability Was. On the other hand, the fluorine resin having a fluorine-containing aliphatic ring structure, polyfluoro repellent than the fluorine-containing polymer to have a alkyl group slightly worse, also film water-repellent oil-repellent treatment of cotton cloth for good When I did, the texture was inferior.

[0004]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned disadvantages of the prior art, and provides a main polymer obtained by cyclopolymerizing a fluorine-containing monomer having two polymerizable double bonds. Fluororesin having a fluorinated aliphatic ring structure in the chain
And 95 wt%, based on acrylate or methacrylate having a number 4-20 polyfluoroalkyl group having a carbon
A water- and oil-repellent composition comprising 99 to 5% by weight of a fluorine-containing polymer containing units , and an article coated with this composition.

[0005]

[0006]

[0007] two polymerizable double bonds fluoromonomer having a polymer having a ring structure in its main chain obtained by cyclic polymerization is JP 63-238111 and JP 63
-238115 is known. That is, cyclopolymerization of monomers such as perfluoro (allyl vinyl ether) and perfluoro (butenyl vinyl ether),
Or obtained by copolymerizing a radical polymerizable monomer such as tetrafluoroethylene and the monomer.

Further, perfluoro (2,2-dimethyl-
A monomer having a fluorinated ring structure such as 1,3-dioxole) and a fluorinated monomer having two polymerizable double bonds such as perfluoro (allyl vinyl ether) and perfluoro (butenyl vinyl ether). May be used.

The polymer having a fluorinated aliphatic ring structure is
Polymers having a ring structure in the main chain are preferred, but all monomers
Transparency those containing monomer units at least 20 mol% having a ring structure against over units, preferred from the viewpoint of mechanical properties.

The molecular weight of the polymer having a fluorinated aliphatic ring structure is preferably from 0.01 to 3.0 dl / g in terms of intrinsic viscosity. If the intrinsic viscosity is too low, the film-forming properties are poor, and if it is too high, the solubility in a solvent is poor.

The glass transition point T _g (° C.) of the polymer having a fluorinated aliphatic ring structure is determined by the heat-resistant temperature T of the substrate to be coated.
(° C.), it is preferable that T _g <T + 40.

The polymer having a fluorinated aliphatic ring structure preferably contains a terminal group which reacts with a substrate to be coated. Examples of the terminal group carboxylic acid, carboxylic acid ester, fluoride acids, but silyl-modified carboxylic acids are exemplified, Lena had limited thereto.

The acrylate or methacrylate having a polyfluoroalkyl group in the present invention (hereinafter referred to as (meth)
Fluoropolymers containing units based on acrylates) are polyfluoroalkyl groups (hereinafter abbreviated as Rf groups).
It is a homopolymer obtained by radical polymerization of the contained (meth) acrylate or a copolymer of the Rf group-containing (meth) acrylate and a radical polymerizable unsaturated monomer (hereinafter abbreviated as a comonomer).

The Rf group-containing (meth) acrylate is represented by R
the f group is an acryl group, either directly or via a divalent linking group;
It has a structure bonded to a methacryl group (hereinafter abbreviated as (meth) acryl group) . As the structure of the Rf group, a structure in which a hydrogen atom in a hydrocarbon group such as a linear or branched alkyl group or an alkenyl group is usually substituted with a fluorine atom is usually selected. It may have a structure having a modified oxygen atom. In the present invention, the Rf group has 4 to 20 carbon atoms, preferably 4 to 16 carbon atoms.

[0015] While the Rf group is a group have a 2 or more fluorine atoms, preferably a group more than 80% of the atoms bonded to the carbon atom is a fluorine atom. Further, other atoms other than a fluorine atom and a hydrogen atom may be bonded to the carbon atom. As the other atoms, a chlorine atom is preferable.

[0016] When the Rf group is a group which have a carbon atom and an ether bonded oxygen atom, group containing oxyfluoroalkylene portion in the structure is preferable. Further, it may be a group containing a structure in which two or more oxyfluoroalkylenes are linked. Examples of the oxyfluoroalkylene moiety include oxyfluoroethylene, oxyfluoropropylene.

As the structure of the terminal portion of the Rf group, a trifluoromethyl group, a difluoromethyl group, a chlorodifluoromethyl group or the like is selected, and a preferred structure is a trifluoromethyl group.

The most preferred Rf group is represented by C _n F _{2n + 1} .
Rf group in which all of the hydrogen atoms are replaced by fluorine atoms (hereinafter referred to as perfluoroalkyl group). The perfluoroalkyl group preferably has a linear structure, and preferably has 4 to 20 carbon atoms, particularly preferably 6 to 12 carbon atoms.

The Rf group is bonded to the (meth) acryl group directly or via a divalent bonding group. Examples of the divalent linking ^{group, -R 2 -, -R 2 N} (R 3) SO 2 -, -
R ² N (R ³ ) CO— and the like, but are not limited to these examples. Here, R ² is an alkylene group, which is usually an alkylene group having 2 to 6, preferably 2 carbon atoms. R ² may be an alkylene group containing an ether-bonded oxygen or a phenylene group. An alkyl group, a halogen atom and the like may be bonded to the alkylene group. R ³ represents an alkyl group, and preferably has 1 to 4 carbon atoms.

Specific examples of the (meth) acrylate containing an Rf group are shown below , but are not limited to these examples . In the following , R ¹ represents a hydrogen atom or a methyl group, and φ represents a phenylene group. Rf 'is a perfluoroalkyl group having 4 to 16 carbon atoms.

[0021] ^{_{C H 2 = C (R 1}} ) COOCH 2 CH 2 Rf ', CH 2 = C (R 1) COOCH (CH 3) CH 2 Rf', CH 2 = C (R 1) COOCH 2 CH 2 N (CH ₃ ) CORf ' , CH ₂ = C (R ¹ ) COOCH ₂ CH ₂ N (C ₂ H ₅ ) CORf' , CH ₂ = C (R ¹ ) COOCH ₂ CH ₂ N (C ₃ H ₇ ) CORf ' , CH ₂ = C (R ¹ ) COOCH ₂ CH ₂ N (CH ₃ ) SO ₂ Rf ' , CH ₂ = C (R ¹ ) COOCH ₂ CH ₂ N (C ₃ H ₇ ) SO ₂ Rf' , CH ₂ = ^{C (R 1) COOCH (CH} 2 Cl) CH 2 OCH 2 CH 2 N (CH 3) SO 2 Rf ', CH 2 = C (R 1) COOCH 2 CH 2 φCH 2 OCH 2 CH 2 CH 2 Rf'.

Examples of the comonomer, if a monomer having a known radical polymerizable unsaturated groups, various ones may be mentioned, without particular limitation, for example, acrylates, meth acrylates (hereinafter acrylate And methacrylates are referred to as (meth) acrylates.
The same is true of the other compounds), (meth) acrylamides, (meth) acrylonitrile, etc. olefins, monomers having a radical polymerizable unsaturated group can be selected.

[0023] Specific examples of co-monomers in the following, Lena had limited to these examples. 2-ethylhexyl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, (meth) acrylic acid, polyoxyalkylene (meth) acrylate, glycidyl (meth) acrylate, benzyl (meth) acrylate, isocyanatoethyl ( (Meth) acrylate, aziridinyl (meth) acrylate, hydroxyalkyl (meth) acrylate, and (meth) acrylate having a polysiloxane moiety.

(Meth) acrylamide, diacetone (meth) acrylamide, methylolated (meth) acrylamide, vinyl acetate, vinyl chloride, vinyl fluoride, vinyl alkyl ether, halogenated alkyl vinyl ether, vinyl alkyl ketone, N-vinyl carbazole,
Ethylene, butadiene, isoprene, chloroprene, styrene, α-methylstyrene, p-methylstyrene, maleic anhydride. The above comonomers can be used in combination on two or more kinds.

[0025] Of these comonomers, vinegar Teariru
(Meth) alkyl acrylates such as A acrylate and / or vinyl chloride are preferred.

[0026] In the copolymerization of (meth) acrylate and a comonomer of Rf group-containing, Rf group-containing (meth)
It is preferable that the proportion of the acrylate is 60% by weight or more, particularly 80% by weight or more.

The homopolymerization of the Rf group-containing (meth) acrylate or the copolymerization with a comonomer can be carried out by solution polymerization in a fluorinated solvent, emulsion polymerization in an aqueous medium, or suspension polymerization in an aqueous medium.

The homopolymerization or copolymerization is usually carried out in the presence of a radical polymerization initiator. Known compounds can be used as the radical polymerization initiator. The radical polymerization initiator can be used alone or in combination of two or more. The amount of the radical polymerization initiator is usually from 0.01 to 3 parts by weight, preferably from 0.1 to 1 part by weight, based on 100 parts by weight of all monomers.
1.5 parts by weight is good.

[0029] The number average molecular weight of the fluoropolymer which have a polyfluoroalkyl group 1,000～1,000,00
0 is preferred. Number average molecular weight of 1,000 to 200,0
00 is particularly preferable from the viewpoint of solubility or dispersibility in a solvent.

The ratio of the fluoropolymer to have a fluorine resin and a polyfluoroalkyl group in a main chain having a fluorinated aliphatic ring structure of the present invention is between a pair 99 for normal 95: 5 However, this ratio can be appropriately changed depending on the use, purpose, processing method and the like. Usually, the composition of the present invention is used after further diluting with a solvent 10 to 1000 times at the time of coating. For example, when the water- and oil-repellent composition produced in the present invention is applied to a fiber woven fabric or a fiber knitted fabric, the composition is adjusted so as to be about 0.2 to 2% by weight.

The above composition can be prepared in an arbitrary form such as a coating solution using an organic solvent, an aqueous emulsion, an aerosol or the like according to a conventional method.

The solvent of the coating solution contains a fluororesin having a fluorinated aliphatic ring structure in the main chain and a polyfluoroalkyl group .
Those fluorine-containing polymer to be closed both dissolved or dispersed is preferred. The solvent of the coating liquid is preferably a fluorine-based solvent.
Examples of the fluorine-based solvent are shown below, but are not limited to these examples.

The perfluoro benzene, polyfluoro aromatic compounds such as hexafluoro-xylene. Polyfluorotrialkylamine compounds such as perfluorotributylamine and perfluorotripropylamine . Perfluorohexane, perfluorooctane, (perfluoro-n-octyl) ethane, perfluoro (2,3,
5-trimethyl hexane) of which polyfluoroalkanesulfonic compound. (Perfluoro-n-octyl) polyfluoroolefin compounds such as ethylene . Polyfluorocycloalkane compounds such as perfluorocyclohexane and perfluorodecalin . Polyfluoro cyclic ether compounds such as perfluoro (2-butyltetrahydrofuran) ; Chlorofluorocarbons such as Application Benefits chlorotrifluoroethane. 1,3-dichloro-1,1,2,2,3-
Pentafluoropropane, 3,3 -dichloro- 1,1,
Chlorofluorohydrocarbons such as 1,2,2 -pentafluoropropane . Etc. Fluorine-containing low molecular weight polyether. These solvents may be used alone or in combination.

Further, the above-mentioned composition can be applied to the article to be treated by an arbitrary method depending on the kind of the article to be treated, the preparation form and the like. For example, in the case of a coating liquid, a method of adhering it to the surface of an object to be processed and drying it by a known method of coating processing such as coating is adopted. If necessary, curing may be performed to improve the adhesion to the object.

Furthermore the compositions may contain other water repellents or oil repellents, or crosslinking agents, insect repellents, flame retardants, antistatic agents, can be appropriately contain additives such as anti-wrinkle agent.

Articles to which the water / oil repellent composition of the present invention can be applied include various examples without particular limitation. For example <br/>, fiber維織product, fiber knitted, glass, wood, leather, fur, asbestos, brick, cement, metal, metal oxide, ceramic product,
Although it is a plastic or the like, it is not limited to these examples . Fiber
維織was cotton Examples of fibers knitted, hemp, wool, animal and plant natural fibers such as silk, polyamide, polyester, polyvinyl alcohol, polyacrylonitrile, polyvinyl chloride, synthetic fibers such as polypropylene, rayon, semisynthetic fibers such as acetate , glass fibers, inorganic fibers carbon fiber 維等, or woven or knitted of these mixed fibers thereof. Cotton, the proportion of the fluorine-containing polymer having a Rf group in order not to impair the texture when applied to leather is 60 fold
Preferably , the amount is at least%. Article fishing line, the nozzles of an ink jet printer, the ratio of the fluorine-containing polymer having a Rf group in the case of a printed wiring board 70 fold
Since Ah Ru and good durability in an amount percent preferred.

[0037]

EXAMPLES Next, examples further specifically described the present invention, the present invention in this description is not limited.

Synthesis Example 1 30 g of perfluoro ( butenyl vinyl ether ) , 120 g of ion-exchanged water , 4.8 g of methanol and 76 mg of ((CH ₃ ) ₂ CHOCOO) ₂ as a polymerization initiator were used to prepare an inner volume of 200 m.
1 autoclave made of pressure-resistant glass. After purging the system with nitrogen three times, suspension polymerization was performed at 40 ° C. for 22 hours. After the obtained polymer was isolated, it was heat-treated at 300 ° C. and washed with water. As a result, 26 g of polymer A was obtained. The intrinsic viscosity [η] of this polymer was 0.34 dl / g in perfluoro (2-butyltetrahydrofuran) at 30 ° C. The glass transition point of the polymer was 108 ° C., tough transparent Tsu der vitreous polymer at room temperature. Light transmittance is 95%
Above was high. Infrared spectroscopy showed absorption of the carboxylic acid.

[0039] Synthesis Example 2 fluoroacrylate _{(CH 2 = CHCOOCH 2 CH 2} C n F 2n + 1: 9 n is on average) 5 g, 1,1,2-trifluoro-trichloroethane 68 g, and azobisisobutyronitrile as a polymerization initiator 0.52 g of butyronitrile was placed in a pressure-resistant glass ampoule.
After purging the system with nitrogen three times, polymerization was carried out at 60 ° C. for 15 hours. As a result, 2.2 g of polymer B was obtained. Polymer B
Had a number average molecular weight of 10,000.

[0040] Synthesis Example 3 fluoroacrylate _{(CH 2 = CHCOOCH 2 CH 2} C n F 2n + 1: n is on average 9) 15 g, stearyl acrylate 0.13
g, 1,1,2-trifluorotrichloroethane 39
g, stearyl mercaptan 0.37 g, and azobisisobutyronitrile 0.26g were put in a pressure glass ampoule as a polymerization initiator. After purging the system with nitrogen three times, polymerization was carried out at 60 ° C. for 15 hours. As a result, 12.3 g of polymer C was obtained. The composition (weight ratio) of polymer C was 99: 1 fluoroacrylate to stearyl acrylate.
And the number average molecular weight was 100,000.

[0041] Synthesis Example 4 fluoroacrylate _{(CH 2 = CHCOOCH 2 CH 2} C n F 2n + 1: n is on average 9) 15 g, stearyl acrylate 0.20
g, 1,1,2-trifluorotrichloroethane 39
g, stearyl mercaptan 0.66 g, and azobisisobutyronitrile 0.26g were put in a pressure glass ampoule as a polymerization initiator. After purging the system with nitrogen three times, polymerization was carried out at 60 ° C. for 15 hours. As a result, 12.8 g of polymer D was obtained. The composition (weight ratio) of polymer D was 99: 1 fluoroacrylate to stearyl acrylate.
And the number average molecular weight was 80,000.

Example 1 0.6 part (parts by weight of polymer A) obtained in Synthesis Example 1
Like) and 0.4 part of the polymer B obtained in Synthesis Example 2 were dissolved in 50 parts of perfluoro (2-butyltetrahydrofuran),
A solution in which both polymers were dissolved was prepared. Then, soak the glass plate was washed using an ultrasonic washing machine in the solution, which raised at a constant rate. When the glass plate was dried at 80 ° C. for 1 hour , a uniform coating film of the polymer mixture could be formed on the glass plate.

When the contact angle of the droplet on the surface of this film was measured, it was 111 ° when water was used as the droplet and 62 ° when isopropyl alcohol (IPA) was used. It turned out to show.

[0044] In addition, when the durability of the coating was evaluated by the method shown in Table 1, as shown in Table 2, it was found that durability is also good.

[0045]

[Table 1]

Example 2 A solution in which both polymers were dissolved was prepared in the same manner as in Example 1 except that polymer C was used instead of polymer B, and dip coating was performed. A film could be formed. When the contact angle of the surface of this film was measured, it was 115 ° for water and 59 ° for IPA. The durability test of the film was performed by the method shown in Table 1.

Example 3 A solution in which both polymers were dissolved was prepared in the same manner as in Example 1 except that polymer D was used instead of polymer B, and dip coating was performed. A film could be formed. The contact angle of the film surface was measured and found to be 117 ° for water and 59 ° for IPA. The durability test of the film was performed by the method shown in Table 1.

Example 4 0.4 part of the polymer A obtained in Synthesis Example 1 and 0.6 part of the polymer B obtained in Synthesis Example 2 were dissolved in 50 parts of perfluoro (2-butyltetrahydrofuran). A solution in which both polymers were dissolved was prepared. Next, raised at a constant speed immersed glass plate was washed by an ultrasonic cleaner in the solution. Was the glass plate was dried for 1 hour at 80 ° C., heavy on a glass plate
A uniform coating film of the coalesced mixture could be formed.

When the contact angle of the droplet on the surface of this film was measured, water was 115 ° and IPA was 61 °.
It was found to exhibit excellent water and oil repellency. When the durability of the film was evaluated by the method shown in Table 1, it was shown in Table 2.
As described above , it was found that the durability was good.

Example 5 0.2 part of the polymer A obtained in Synthesis Example 1 and 0.8 part of the polymer B obtained in Synthesis Example 2 were dissolved in 50 parts of perfluoro (2-butyltetrahydrofuran). A solution in which both polymers were dissolved was prepared. Then, soak the glass plate was washed using an ultrasonic washing machine in the solution, which raised at a constant rate. When this glass plate was dried at 80 ° C. for 1 hour, it was placed on the glass plate.
An almost uniform coating film of the polymer mixture could be formed.

When the contact angle of the droplet on the surface of this film was measured, the water was 117 ° and the IPA was 62 °.
It was found to exhibit excellent water and oil repellency. When the durability of the film was evaluated by the method shown in Table 1, it was shown in Table 2.
As described above , it was found that the durability was good.

Comparative Example 1 When a coating film was formed on a glass plate using only polymer B without using polymer A, the film was slightly uneven and fine irregularities in particles were observed. Contact angle is water: 108 °, I
PA: 56 °, but the dispersion of the measured values was large. Next, when the durability was evaluated in the same manner as in Example 1, peeling of the film was observed.

Comparative Example 2 When a coating film was formed on a glass plate using only the polymer C, the film was slightly uneven, and fine irregularities in the form of particles were observed. The contact angle was 112 ° for water and 60 ° for IPA. Next, when the durability was evaluated in the same manner as in Example 1, peeling of the film was observed.

Comparative Example 3 When a coating film was formed on a glass plate using only the polymer D, the film was slightly non-uniform and fine irregularities in the form of particles were observed. The contact angles were 103 ° for water and 59 ° for IPA. Next, when the durability was evaluated in the same manner as in Example 1, peeling of the film was observed.

Comparative Example 4 A coating film was formed on a glass plate using only the polymer A. The coating was uniform. Contact angle: water: 103 °, IP
A: 55 °. Next, the durability was evaluated in the same manner as in Example 1. The above Examples 1 to 5 and Comparative Examples 1 to
Table 2 shows the coating film surface condition and the durability evaluation results in Example 4.
You.

[0056]

[Table 2]

Example 6 0.1 part of the polymer A obtained in Synthesis Example 1 and 0.9 part of the polymer C obtained in Synthesis Example 3 were dissolved in 100 parts of perfluoro (2-butyltetrahydrofuran). A solution in which both polymers were dissolved was prepared. Then, the solution was sprayed on cotton cloth, 1
Dried at 50 ° C. As a result, the cotton cloth showed excellent water / oil repellency and durability.

Example 7 3.5 parts of the polymer A obtained in Synthesis Example 1 and 1.5 parts of the polymer C obtained in Synthesis Example 3 were dissolved in 95 parts of perfluoro (2-butyltetrahydrofuran). A solution in which both polymers were dissolved was prepared. Next, this solution was applied to the aluminum-made mold 2 hours at 50 ° C., dried for 1 hour and then at 100 ° C..

[0059] The urethane resin mixed well and poured into a mold to obtain a molded article is cured by heating for 3 minutes at 65 ° C..
(Before the mold is contaminated, the continuous number of times moldable or) release persistence in the molding was evaluated secondary workability such as coating property and adhesion, and the obtained molded body. As a result, the sustainability was 32 times, the secondary workability was good, and the cleaning of the surface of the molded body was insoluble.

Example 8 0.1 part of the polymer A obtained in Synthesis Example 1 and 0.1 part of the polymer C obtained in Synthesis Example 3 were dissolved in 95 parts of perfluoro (2-butyltetrahydrofuran). A solution in which both polymers were dissolved was prepared. Next, a nylon fishing line was immersed in this solution, taken out, and air-dried. Furthermore, it dried at 70 degreeC for 1 hour. The water out of the fishing line is well, the goodness of the drainage was not impaired even after you have saved to 100 hours underwater.

Example 9 0.1 part of the polymer A obtained in Synthesis Example 1 and 0.1 part of the polymer C obtained in Synthesis Example 3 were dissolved in 95 parts of perfluoro (2-butyltetrahydrofuran). A solution in which both polymers were dissolved was prepared. Next, to form a coating coating film of the solution to UV ozone treatment and the silane coupling agent-treated Porisuru phon board. When the contact angle of the ink for an ink jet printer was measured on this film, it showed excellent liquid repellency. When this plate was immersed in the ink at 60 ° C. for 7 days, the contact angle was measured again and found no change.

[0062]

The water- and oil-repellent composition of the present invention surprisingly surprisingly comprises a fluorinated resin having a fluorinated aliphatic ring structure alone or an acrylate having a polyfluoroalkyl group.
Alternatively, the fluorinated polymer containing a methacrylate-based unit alone stably exhibits a water / oil repellency that is superior to the water / oil repellency. Further, when coated, it has excellent film-forming properties and is given durability.

The water and oil repellent composition of the present invention exhibits excellent water and oil repellency when applied to cotton cloth, and also has excellent durability. When the water- and oil-repellent composition of the present invention is applied to a mold,
The mold release durability of the molding resin (how many times the molding can be performed continuously before the mold is contaminated) and the secondary workability such as paintability and adhesiveness are good. If water and oil repellent composition of the present invention is adapted to the fishing line, the water out of the fishing line may, durability of the drainage is good.

When the water / oil repellent composition of the present invention is applied to a nozzle of an ink-jet printer, the ink for the ink-jet printer can be cut easily and the printing is beautiful. Water and oil repellent composition of the present invention when applied to a printed wiring board, a flux creeping of the printed wiring board can be prevented well. When the water and oil repellent composition of the present invention is applied to leather products such as shoes and bags, leather products such as shoes and bags
Shows the excellent water and oil repellency is to prevent the ingress of water on a rainy day,
Its durability is also excellent.

Continuation of the front page (51) Int.Cl. ⁷ Identification symbol FI C09D 137/00 C09D 137/00 C09K 3/18 102 C09K 3/18 102 (56) References JP-A-4-204504 (JP, A) JP-A-2-292349 (JP, A) JP-A-5-1197 (JP, A) JP-A-2-129254 (JP, A) JP-A-4-189862 (JP, A) JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08L 27/12-27/20 C08L 33/16 C08L 37/00 C09D 127/12-127/20 C09D 133/16 C09D 137 / 00 C09K 3/18 102-103

Claims (3)

(57) [Claims] 1. A fluororesin having a fluorinated aliphatic ring structure in the main chain obtained by cyclopolymerization of a fluorinated monomer having two polymerizable double bonds, from 1 to 95% by weight, and from 4 to 4 carbon atoms.
Acrylate having 20 polyfluoroalkyl groups
Alternatively, a water / oil repellent composition comprising 99 to 5% by weight of a fluoropolymer containing a unit based on methacrylate . The fluoropolymer having a wherein polyfluoroalkyl group, C _n F as polyfluoroalkyl group
The composition according to claim 1, which is a fluoropolymer containing at least 80% by weight of a unit based on acrylate or methacrylate having _{2n + 1} (an integer of 20 ≧ n ≧ 4). 3. An article coated with the composition according to claim 1.