JPH09118872A - Improved antifouling composition for surface of sealing material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an antifouling composition which is prepared by dispersing a fluorine resin in an aqueous medium and imparts an excellent antifouling property to the surfaces of sealing, in addition, applicable to sealing materials which is readily erosidle by solvent, since this composition is in an aqueous system. SOLUTION: A fluorine resin (B) is dispersed in an aqueous medium (A). The component B in an amount of preferably 5-30 pts.wt. is dispersed in 100 pts.wt. of the component A. The component B is preferably a copolymer containing polymerized (meth) acrylate units containing perfluoroalkyl group. As the copolymerization components of the component B, vinyl chloride and stearyl acrylate are cited because they readily give high antifouling properties. The aqueous medium (component A) may be only water or a combination thereof with a water-soluble organic solvent, but the amount of the water-soluble organic solvent is preferably 0.1-10 pts.wt. in the component A. The addition of a fluorine surfactant bearing a perfluoroalkyl group and a hydrophilic group as a leveling surfactant is desirable decease the wettability is increased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a composition for antifouling a surface of a sealing material and a method for antifouling the surface of a sealing material using the composition. The sealing material surface antifouling composition of the present invention is a composition effective for preventing adhesion of dirt, such as dust, to the surface of the sealing material applied to joints of interiors and exteriors of general buildings in particular. .

[0002]

2. Description of the Related Art Silicone-based, modified silicone-based, polysulfide-based, modified polysulfide-based, and polyurethane-based sealing materials have been known as sealing materials applied to joints of interiors and exteriors of general buildings. There is. Sealing materials are originally used for the purpose of filling the joints and gaps between various members and imparting water-tightness, airtightness, etc., but in recent years, joints and the surroundings of joints are contaminated even if waterproof performance is secured. As a result, the appearance may be unsightly and the appearance may be impaired. Therefore, the property that stains do not adhere (hereinafter referred to as antifouling property) has also been required.

Among conventional sealing materials, modified silicone-based, modified polysulfide-based, and polyurethane-based sealing materials are widely used because they are excellent in durability and weather resistance and have various properties in a well-balanced manner. However, since the surface remains tacky even after curing, it does not stain the area around the joints, but it has the drawback that dust in the atmosphere adheres to the joints and impairs the appearance. Especially in the Kanto region, remarkable stains were observed on the surface of the sealing material due to the influence of the Kanto loam layer.

Therefore, a method of applying a dust-preventing agent on the surface to provide a barrier layer after the sealing material is cured has been used. However, in the method of applying after the sealing material is cured, there is a problem that the adhesion of dust cannot be prevented until the sealing material is cured. Therefore, there has been proposed a method of applying a solvent-based coating agent containing a fluororesin as a main component when the sealing material is uncured (Japanese Patent Application Laid-Open No. HEI 2).
-182767, JP-A-7-118572).

[0005]

However, in this method, there are problems that the sealing agent is attacked by the solvent contained in the coating agent, the plasticizer is extracted, and the wall material around the sealing material is discolored. There is a problem that the sealing material that can be used is limited. Further, there is a problem in that the organic solvent is volatilized, which is not preferable in terms of environment.

[0006]

The present invention has been made to solve the above problems, and dust, dust, etc. are formed on the surface of a sealing material applied to joints of interiors and exteriors of general buildings. The present invention provides a composition that effectively prevents the adhesion of dirt.
That is, the present invention relates to an aqueous medium, a sealing material surface antifouling composition containing a fluororesin dispersed in the aqueous medium, and an antifouling method using the composition.

The sealant surface antifouling composition of the present invention is a composition containing an aqueous medium and a fluororesin dispersed in the aqueous medium. The molecular weight of fluororesin is 1-10
About 10,000 is preferable. Examples of the fluororesin include known or well-known fluorine-containing resins, for example, a polymer containing a polymerized unit of acrylate or methacrylate containing a polyfluoroalkyl group, a polymer containing a polymerized unit of chlorotrifluoroethylene. Examples thereof include a polymer and a polymer containing a polymerized unit of tetrafluoroethylene. The fluororesin in the present invention is preferably a fluororesin containing a polyfluoroalkyl group.

The polyfluoroalkyl group will be referred to as an R ^f group below. The R ^f group represents a group in which two or more hydrogen atoms of the alkyl group are substituted with fluorine. The R ^f group preferably has 1 to 20 carbon atoms, and particularly preferably 4 to 16 carbon atoms. R
^{The f} group preferably has a linear or branched structure. In the case of a branched structure, it is preferable that the branched portion is present at the terminal portion of the R ^f group and is a short chain having about 1 to 3 carbon atoms. Further, the R ^f group may contain a halogen atom other than a fluorine atom, and the halogen atom is preferably a chlorine atom. When it contains a chlorine atom, it is preferably present in the terminal portion. Further, the R ^f group may have an etheric oxygen atom inserted between the carbon-carbon bonds.

[0009] R number of fluorine atoms in the ^f group, (R ^f number of fluorine atoms in the group) / (R ^f number of hydrogen atoms contained in the alkyl group of the same number of carbon atoms corresponding to the group) × 100 (%)
When expressed by, it is preferably 60% or more, particularly preferably 80% or more, and further preferably substantially 100%. The R ^f group in which substantially all the hydrogen atoms of the alkyl group are replaced with fluorine atoms is referred to as a perfluoroalkyl group.

The carbon number of the perfluoroalkyl group is 4 to 1
6 is preferable, and 6 to 12 is particularly preferable. Further, the perfluoroalkyl group preferably has a linear or branched structure, and preferably a linear structure. The perfluoroalkyl group may have an etheric oxygen atom inserted between carbon-carbon bonds.

[0011] As the polymer containing ^the R ^f group, polymer obtained by polymerizing a polymerizable monomer having an unsaturated bond ^the R ^f group and a polymerizable, and the like, a polymer containing a perfluoroalkyl group Is preferred.

As the fluororesin in the present invention, R ^f
Polymers containing polymerized units of acrylates containing groups or methacrylates containing R ^f groups are preferred. In the following, acrylate and methacrylate are collectively referred to as "(meth) acrylate", and other compounds are also described in the same manner. Also, by collectively methacrylate containing ^the R ^f group containing (meth) acrylate or R ^f group referred to as ^"the R ^f group-containing (meth) acrylate".

Examples of the R ^f group-containing (meth) acrylate include, but are not limited to, the following examples. In the following, R ^f represents an R ^f group having 1 to 20 carbon atoms, preferably a perfluoroalkyl group, and R ⁴ represents a hydrogen atom or a methyl group.

[0014]

[Chemical 1] CH ₂ = CR ⁴ COOCH ₂ CH ₂ R ^f CH ₂ = CR ⁴ COOCH ₂ CH ₂ N (C ₃ H ₇ ) COR ^f CH ₂ = CR ⁴ COOCH (CH ₃ ) CH ₂ R ^f CH ₂ = CR ⁴ COOCH ₂ CH ₂ N (CH ₃ ) SO ₂ R ^f CH ₂ = CR ⁴ COOCH ₂ CH ₂ N (CH ₃ ) COR ^f CH ₂ = CR ⁴ COOCH ₂ CH ₂ N (C ₂ H ₅ ) SO ₂ R ^f CH ₂ = CR ⁴ COOCH ₂ CH ₂ N (C ₂ H ₅ ) COR ^f CH ₂ = CR ⁴ COOCH ₂ CH ₂ N (C ₃ H ₇ ) SO ₂ R ^f CH ₃ = CR ⁴ COOCH (CH ₂ Cl) CH ₂ OCH ₂ CH ₂ N (CH ₃ ) SO ₂ Rf

The polymer containing polymerized units of ^the R ^f group-containing (meth) acrylate may be a polymer comprising one or more polymerized units of ^the R ^f group-containing (meth) acrylate, R ^It may be a copolymer containing polymerized units of one or more of ^f- group-containing (meth) acrylates and another monomer having a radical-polymerizable unsaturated bond. Moreover, when the polymerized unit of the R ^f group-containing (meth) acrylate is contained in two or more kinds, two or more kinds in which the carbon number of the R ^f group is different can be used together.

The polymer containing the polymerized units of the R ^f group-containing (meth) acrylate is a polymer of another radically polymerizable unsaturated bond-containing monomer (hereinafter referred to as other monomer). Copolymers containing units are preferred. The other monomer may be contained alone or in combination of two or more.

As other monomers, vinyl chloride and stearyl acrylate are particularly preferably used from the viewpoint that high antifouling property can be easily obtained. In addition, ethylene, vinyl acetate, vinyl fluoride, halogenated vinyl styrene, α-
Methylstyrene, p-methylstyrene, (meth) acrylic acid and its alkyl ester, poly (oxyalkylene) (meth) acrylate, (meth) acrylamide,
Diacetone (meth) acrylamide, methylolated (meth) acrylamide, N-methylol (meth) acrylamide, vinyl alkyl ether, (halogenated alkyl) vinyl ether, vinyl alkyl ketone, butadiene, isoprene, chloroprene, glycidyl (meth) acrylate, aziridinyl ( (Meth) acrylate, benzyl (meth) acrylate, isocyanatoethyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, maleic anhydride, (meth) acrylate having polysiloxane, N-vinylcarbazole, etc. Is mentioned.

The polymer containing the polymerized units of R ^f group-containing (meth) acrylate is prepared by adding R ^f group-containing (meth) acrylate and, if necessary, other monomers to the aqueous medium in the presence of a surfactant and the like. It is preferable to synthesize by a method of emulsifying in, and polymerizing with stirring. As the polymerization initiation source, various polymerization initiators such as organic acid peroxides, azo compounds and persulfates, and ionizing radiation such as γ-rays can be used.

As the surfactant, almost all nonionic, anionic, cationic and amphoteric surfactants can be used. Among these, nonionic surfactants include alkylphenol ethylene oxide adducts, higher alcohol ethylene oxide adducts, ethylene oxide / propylene oxide block copolymers, alkyl sorbitol ethylene oxide adducts, alkylamine ethylene oxide adducts, alkylamine ethylene oxide propylene oxide. Adducts, alkylamine oxides and the like are preferred.

As the anionic surfactant, alkylbenzene sulfonate, α-olefin sulfonate, alkyl sulfate ester salt, alkyl phenyl ether sulfate ester salt, sulfosuccinate salt and the like are preferable.

As the cationic surfactant, monoalkylammonium chloride, dialkylammonium chloride, alkylammonium chloride ethylene oxide adduct and the like are preferable.

As the amphoteric surfactant, an amino acid type or betaine type surfactant is preferable, and a betaine type surfactant having a high water solubility even at an isoelectric point is particularly preferable. The betaine-type surfactant is preferably a compound represented by the following formula or an imidazoline compound. However, in the following formula, R represents an alkyl group having 1 to 12 carbon atoms, and an alkyl group having 12 carbon atoms is preferable.

[0023]

## STR2 ## ^{_{RN + (CH 3) 2 CH}} 2 COO -

[0024]

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The sealant surface antifouling composition of the present invention is a composition in which the above-mentioned fluororesin is dispersed in an aqueous medium. Further, the concentration of the fluororesin in the aqueous dispersion is preferably about 5 to 30 parts by weight with respect to 100 parts by weight of the aqueous medium. The water-based medium may contain only water or a water-soluble organic solvent together with water. Examples of the water-soluble organic solvent include lower alcohol, glycol, glycol ether and the like. The water-soluble organic solvent has an advantage of improving the wettability to the sealing material, but a small amount is preferable, and 100 parts by weight of the water-based medium contains:
0.1 to 10 parts by weight is preferable.

The fluororesin may be dispersed alone,
It may be dispersed under the action of a surfactant. Also,
The composition of the present invention may contain a leveling surfactant, an ultraviolet absorber, an antioxidant, a viscosity modifier, an antiseptic and fungicide, etc. together with the fluororesin. It is preferable to use an additive that does not affect the sealing material such as discoloration. Further, the amount of the additive can be appropriately changed according to the purpose, and usually 100 ppm to several% is preferable.

The composition of the present invention preferably contains a leveling surfactant as an additive because it enhances the wetting property with respect to the sealing material. The surfactant for leveling is not particularly limited and may be a known surfactant, but in the present invention, a fluorine-based surfactant is preferable, from the viewpoint that the surface shape of the obtained coating film is excellent, and the like. The above-mentioned compound having an R ^f group and a hydrophilic portion is preferable, and a cationic or nonionic R ^f group-containing surfactant is particularly preferable.

The cationic or nonionic R ^f group-containing surfactant is also effective in terms of dispersion stability of the composition, and has the advantage that the effect is exhibited even when added in a small amount.

The R ^f -group-containing surfactant is commercially available, and examples thereof include Surflon, which is a trade name of Asahi Glass Co., Ltd. When the fluorosurfactant is contained, the amount is preferably about 0.05 to 5 parts by weight per 100 parts by weight of the composition. Specific examples of the R ^f -group-containing surfactant are shown below, but the invention is not limited thereto. However, in the following formula, R ^f
Represents the above polyfluoroalkyl group, preferably a perfluoroalkyl group.

[0030]

Embedded image

The composition of the present invention can prevent stains from adhering to the sealing agent by treating the surface of the sealing agent to form a film. The method for treating the composition is not particularly limited, and it is usually preferable to apply the method by applying with a brush, spray or the like. Further, the timing of application may be either after curing of the sealing agent or before curing, but in order to prevent adhesion of dirt during curing of the sealing agent, it is preferable to perform treatment before curing, It is preferable to treat the sealing material immediately after applying it with putty or the like. In addition, a masking tape may be attached in advance in order to prevent adhesion to the wall material around the base during application.

The treated composition is dried to form a fluororesin film on the surface of the sealing agent. The drying may be natural drying or heat drying. In the case of processing in a factory or the like, it is preferable to heat to shorten the drying time and prevent the adhesion of dust before the evaporation of the aqueous medium. Further, the film thickness of the fluororesin film is preferably about 0.1 to 5 μm. If the film thickness is too thin, a sufficient effect cannot be obtained, and if the film thickness is too thick, it causes cracks and is uneconomical.

The sealing material for treating the composition of the present invention is not particularly limited, and can be applied to conventionally used sealing materials. In particular, when the solvent-based coating material is treated, the sealing material is not deteriorated. It can also be used for materials with problems. As the sealing material, a modified silicone-based, modified polysulfide-based, or polyurethane-based sealing material is preferable, and a modified silicone-based or polyurethane-based sealing material is particularly preferable. The modified silicone sealing material means a sealing material containing a hydrolyzable silicone compound in which a hydrolyzable silyl group is bonded to the end of polyether.

As the modified silicone type sealing material,
Cemedine's product name POS seal, POS seal type II, POS seal LM, Sunstar Giken's product name penguin seal 2500 DRY, penguin seal 257
0, commercially available products such as Hamaite Super II and Hamaite Super I manufactured by Yokohama Rubber Co., Ltd. As a polyurethane-based sealing material, trade name S- manufactured by Cemedine
750, product name Penguin seal 98 manufactured by Sunstar Giken Co., Ltd.
0, penguin seal 999, commercial products such as Yokohama Rubber Co., Ltd., trade name Hammatite UH-30, and Hamatite Seal Ace.

[0035]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited thereto.

[Evaluation Method of Antifouling Property] A joint having a width of 10 mm was made with a slate having a thickness of 6 mm, and a masking tape was attached along the joint. 1-component modified silicone sealant between joints with a width of 10 mm (trade name PO manufactured by Cemedine Co., Ltd.
S seal) and a polyurethane-based sealing agent (Hamatite product name UH-30 manufactured by Yokohama Rubber Co., Ltd.) were filled, and the surface of the sealing material was pressed with a spatula to finish the surface flat. Immediately after that, the following composition was spray-coated with a sprayer to a film thickness of 1 to 5 μm. Then, the masking was immediately removed, and the mask was directly attached to an outdoor exposure table having an angle of 45 degrees on the south surface and exposed. After 7 days, 1 month, and 6 months, the surface condition was visually observed to evaluate A to D.

A: Almost no dirt adhered. B: Some dirt is attached. C: Black and dirty. D: There is remarkable stain.

Example 1 Perfluoroalkylethyl acrylate (wherein the carbon number of the perfluoroalkyl group is 6,
It is a mixture of 8, 10, 12, 13, and 16 and has an average carbon number of 9. ) 70 parts by weight, vinyl chloride 20
18.8 wt% of a copolymer (average molecular weight is 40,000) obtained by copolymerizing 1 part by weight, 8 parts by weight of dioctyl malate, and 2 parts by weight of hydroxyethyl acrylate, and polyethylene glycol monononylphenyl ether into the copolymer. On the other hand, an aqueous dispersion containing 1.2% by weight was prepared. 45 parts by weight of the aqueous dispersion was diluted with 55 parts by weight of deionized water and used as a leveling agent, C _n F _{2n + 1} CONH (CH
^{_{2) 3 N + (CH 3}} ) 2 I - ( the number of carbon atoms n is 6,8,1
It is a mixture of 0, 12, 13, and 16 and has an average carbon number of 9. ) Was added to the surface of the POS seal with a sprayer for evaluation. Table 1 shows the results. Further, when the masking tape was peeled off, no adhesion of the composition to the masking tape was observed, and the surface of the sealing agent after 6 months of exposure was smooth and hard, and no crack was observed.

Example 2 Composition 1 was treated on the surface of UH-30 and evaluated. Table 1 shows the results.

[Comparative Examples 1 and 2] POS seals (Comparative Example 1) or UH-30 (Comparative Example 2), which were not coated with the composition of Example, were similarly exposed and compared. Table 1 shows the results.

[0041]

[Table 1]

[0042]

The composition of the present invention can impart antifouling property to the surface of the sealing material by treating it.
Further, since it is a water-based composition, it can be applied to a sealing material made of a material that is easily attacked by a solvent, and is advantageous in terms of working environment. In addition, the sealing material can be treated when it is uncured to prevent the adhesion of dirt at the uncured stage. Also,
Since the obtained coating film is also excellent in releasability, the masking tape can be removed without peeling the coating film even when the composition of the present invention is treated by applying the masking tape.

Front page continuation (72) Inventor Yoko Ikemoto 2-23-1, Hatchobori, Chuo-ku, Tokyo Asahi Glass Court And Resin Co., Ltd.

Claims (9)

[Claims] 1. A sealant surface antifouling composition comprising an aqueous medium and a fluororesin dispersed in the aqueous medium. 2. The surface antifouling composition for a sealing material according to claim 1, wherein the fluororesin is a polymer containing a polyfluoroalkyl group. 3. The sealant surface antifouling composition according to claim 1, wherein the fluororesin is a polymer containing a perfluoroalkyl group having 4 to 20 carbon atoms. 4. The sealant surface antifouling composition according to claim 1, wherein the fluororesin is a polymer containing a polymerized unit of an acrylate or a methacrylate containing a perfluoroalkyl group. 5. The sealant surface antifouling composition according to claim 1, which contains a fluorine-based surfactant composition. 6. A method for antifouling a surface of a sealing material, which comprises forming a film of the composition for antifouling surface of a sealing material according to any one of claims 1 to 5 on the surface of the sealing material. 7. The method for antifouling the surface of a sealing material according to claim 6, wherein the coating has a film thickness of 0.1 to 5 μm. 8. The method for antifouling the surface of a sealing material according to claim 6, wherein the sealing material is a modified silicone-based, modified polysulfide-based, or polyurethane-based sealing material. 9. The method for antifouling the surface of a sealing material according to claim 6, wherein the antifouling composition for the surface of the sealing material is treated when the sealing material is uncured.