Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – At least one aryl ring which is part of a fused or bridged...
Reexamination Certificate
2000-04-24
2002-02-26
Michl, Paul R. (Department: 1714)
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
At least one aryl ring which is part of a fused or bridged...
C524S269000
Reexamination Certificate
active
06350806
ABSTRACT:
TECHNICAL FIELD
The present invention relates to an aqueous-dispersing composition of fluorine-containing polymer, particularly an aqueous-dispersing composition of fluorine-containing polymer containing a colloidal silica and an organoalkoxysilane. The composition can be suitably used for various coatings or paints excellent in stain-proofing property, stain removable property and storage stability.
1. Background Art
In the field of paints, an aqueous dispersion prepared in combination use of a fluorine-containing polymer with colloidal silica and further organoalkoxysilane has been proposed. For example, JP-A-8-120210 discloses an aqueous-dispersing composition comprising an aqueous dispersion of composite resins composed of vinylidene fluoride copolymer and acrylic resin, a colloidal silica and further an organoalkoxysilane. However when an adding amount of colloidal silica is increased, there are problems that a desired gloss of a coating film is not obtained and cracking occurs. Thus there is a limit in hardness of the obtained coating film. As a result, stain-proofing property and stain removable property which are objects of the present invention are not satisfied. Also JP-A-7-53911 discloses a fluorine-containing coating composition comprising an aqueous dispersion of fluoroolefin polymer and an inorganic silicon compound as essential components. However there was a problem that the coating composition does not have enough storage stability as an aqueous dispersion for paints.
In view of the mentioned points, an object of the present invention is to obtain an aqueous-dispersing composition of fluorine-containing polymer which can give excellent stain-proofing property, stain removable property and storage stability when prepared by a combination of a specific fluorine-containing polymer with colloidal silica and organoalkoxysilane and added to a paint.
2. Disclosure of Invention
The present invention was made to solve the above-mentioned problem and relates to the aqueous-dispersing composition comprising an aqueous dispersion of fluorine-containing polymer particles, a colloidal silica and a organoalkoxysilane, and containing said colloidal silica, in solid content, in an amount of more than 50 parts by weight up to 300 parts by weight and said organoalkoxysilane in an amount of 0.1 to 20 parts by weight on the basis of 100 parts by weight in solid content of an aqueous dispersion of fluorine-containing polymer particles.
In the present invention, it is preferable that the fluorine-containing polymer particles in the above-mentioned aqueous dispersion are fluorine-containing seed polymer particles obtained by seed-polymerizing a monomer having a reactive &agr;,&bgr;-unsaturated group in the presence of fluorine-containing polymer particles.
Also in the present invention, it is preferable that the fluorine-containing polymer in the above-mentioned aqueous dispersion of fluorine-containing polymer particles has at least one functional group selected from —OH group, —COOH group and a hydrolyzable silyl group.
In the present invention, an aqueous dispersion prepared by condensation by adding organoalkoxysilane in the presence of colloidal silica particles is added to the aqueous dispersion of fluorine-containing polymer particles and thus those components form an organic-inorganic complex.
BEST MODE FOR CARRYING OUT THE INVENTION
The aqueous-dispersing composition of the present invention comprises an aqueous dispersion of fluorine-containing polymer particles and specific amounts of colloidal silica and organoalkoxysilane. Each component is explained below.
1. Aqueous Dispersion of Fluorine-containing Polymer Particles
Examples of the fluorine-containing polymer particles are particles of fluoroolefin polymer, copolymers of a fluoroolefin and a monomer copolymerizable with the fluoroolefin, seed polymers of those polymers with a resin containing no fluorine, and the like.
As the above-mentioned fluoroolefin, fluoroolefins having 2 to 4 carbon atoms, for example, vinyl fluoride, vinylidene fluoride (VdF), tetrafluoroethylene (TFE), chlorotrifluoroethylene (CTFE), hexafluoropropylene (HFP), trifluoroethylene, and the like are used.
(1) Fluoroolefin Polymer
Examples of the polymer of the above-mentioned fluoroolefins are, for instance, homopolymers of the above-mentioned fluoroolefins and known copolymers of two or more fluoroolefins. There are homopolymers of VdF, TFE and CTFE, VdF/TFE copolymer, VdF/HFP copolymer, VdF/CTFE copolymer, VdF/TFE/CTFE copolymer, VdF/TFE/HFP copolymer, TFE/HFP copolymer, and the like.
The aqueous dispersions of particles of those fluoroolefin polymers are prepared by usual emulsion polymerization. Namely the aqueous dispersions can be obtained by emulsion-polymerizing a fluoroolefin monomer or a mixture of fluoroolefin monomers in the presence of an emulsifying agent of not more than 5% by weight, preferably not more than 1% by weight on the basis of water.
It is preferable that water to be used in the emulsion polymerization is de-ionized water. Also it is preferable that the emulsifying agent is a fluorine-containing surfactant. Further a reactive fluorine-containing emulsifying agent can also be used. Also a slight amount of non-fluorine-containing nonionic emulsifying agent can be used together.
The fluorine-containing emulsifying agent to be used in the present invention means a compound containing a fluorine atom in its structure and having a surface-activating ability or a mixture of two or more thereof. Examples of the compound are, for instance, an acid represented by X(CF
2
)
n
COOH, in which n is an integer of 6 to 20, X is F or H, its metal salt, ammonium salt, amine salt or quaternary ammonium salt; Y(CH
2
CF
2
)
m
COOH, in which m is an integer of 6 to 13, Y is F or Cl, its metal salt, ammonium salt, amine salt or quaternary ammonium salt; and the like. In addition, it is possible to use a reactive emulsifying agent disclosed in JP-A-8-67795 solely or in combination with the above-mentioned fluorine-containing emulsifying agent. Also it is possible to use a non-fluorine-containing nonionic emulsifying agent disclosed in JP-A-7-90153 together.
(2) Copolymer of Fluoroolefin and Monomer Copolymerizable with Fluoroolefin
As the monomers being copolymerizable with the above-mentioned fluoroolefins, there are, for example, &agr;-olefins such as ethylene, propylene and isobutylene; vinyl ethers such as ethyl vinyl ether (EVE), cyclohexyl vinyl ether (CHVE), hydroxybutyl vinyl ether (HBVE), butyl vinyl ether, isobutyl vinyl ether, methyl vinyl ether and polyoxyethylene vinyl ether; alkenyls such as polyoxyethylene allyl ether, ethyl allyl ether, hydroxyethyl allyl ether, allyl alcohol and allyl ether; vinyl esters such as vinyl acetate, vinyl lactate, vinyl butyrate, vinyl pivalate, vinyl benzoate, and VEOVA9 and VEOVA10 (brand names of Shell Chemical Co., Ltd.); ethylenically unsaturated carboxylic acids such as itaconic anhydride, succinic anhydride and crotonic acid; and the like. Particularly &agr;-olefins, vinyl ethers, vinyl esters and alkenyls are used preferably.
Examples of the above-mentioned copolymers are TFE/propylene copolymer, TFE/ethylene copolymer, TFE/vinyl ester copolymer, TFE/vinyl ether copolymer, HFP/vinyl ether copolymer, HFP/vinyl ester copolymer, CTFE/vinyl ether copolymer, and the like. Further there are polymers comprising three or more monomers, which contain, in addition to the above-mentioned copolymer, a monomer copolymerizable with the above-mentioned fluoroolefin as a modified monomer in an amount of not more than 30% by mole.
The aqueous dispersions of particles of those fluoroolefin copolymers are prepared by usual emulsion polymerization. A process for emulsion polymerization may be the same as the process for polymerization of the fluoroolefin polymer of above (1) except that a mixture of a fluoroolefin and a monomer copolymerizable with the fluoroolefin is used.
It is preferable that the fluoroolefin monomer is contained in the mentioned copolymer of the fluoroolefin and monomer copolymerizable there
Imoto Katsuhiko
Mitsuhata Nobuo
Nagato Masaru
Tsuda Nobuhiko
Daikin Industries Ltd.
Michl Paul R.
LandOfFree
Aqueous fluoropolymer dispersion composition does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Aqueous fluoropolymer dispersion composition, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Aqueous fluoropolymer dispersion composition will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2941935