JP5368951B2 - Water / oil repellent resin composition and coated product - Google Patents

Description

  The present invention relates to a water / oil repellent resin composition used for forming a water / oil repellent coating film, and a coated product having a coating film formed of the water / oil repellent resin composition.

  In recent years, there has been a growing demand for products that retain water and oil repellency functions on the surface, such as water and water stains, which are difficult to remove and are easy to remove, especially in the interior equipment of homes (kitchens, baths, toilets, etc.). It is coming. Usually, a film having a water contact angle of 90 ° or more and an oil (especially oleic acid) contact angle of 40 ° or more is called a water / oil repellent coating, and such a water / oil repellent coating is used. Development of a coating material for forming a film is actively performed (for example, Patent Document 1).

  On the other hand, it is conventionally known to obtain a coating film by curing a resin composition at room temperature. One method for curing such a resin composition at room temperature is to form a urethane resin by crosslinking a polyol resin as a main agent and an isocyanate as a curing agent. Therefore, a resin composition having water and oil repellency at room temperature can be formed by incorporating a fluorine component into the main polyol and binding a water and oil repellent group. However, in such a method, it takes a considerable amount of time to develop sufficient water and oil repellency at room temperature, and the hardness of the coating film can be increased only to about 2H in pencil hardness. It is hard to say that a coating film is obtained. This is because sufficient crosslinkability cannot be obtained by curing at room temperature. In order to obtain excellent crosslinkability at room temperature, a method in which an alkoxysilane and an organic acid are mixed and cured in a fluororesin has also been proposed (Patent Document 2). However, the method disclosed in Patent Document 2 has a problem that water and oil repellency is insufficient although curability at room temperature can be obtained.

JP 2005-120236 A Japanese Patent No. 2945949

  The present invention has been made in view of the above points, a resin composition that is curable at room temperature, has excellent water and oil repellency, and can form a coating film with high hardness, and The present invention provides a coated product having a coating film formed of the resin composition.

  The water / oil repellent resin composition of the present invention has a dimethylsiloxane group represented by the formula (1) in the skeleton, a polyol resin having an alkoxy group and a hydroxyl group as a crosslinking group, and a solid content of the polyol resin. 20 to 100% by mass of a hydrolyzable alkoxysilane or a partially hydrolyzed condensate thereof, and a solid content of a resin component combining the polyol resin and the hydrolyzable alkoxysilane or a partially hydrolyzed condensate thereof. On the other hand, it contains 0.1 to 2.5% by mass of an organic acid and has room temperature curability.

   The coated article of the present invention is characterized in that the water- and oil-repellent resin composition having the above-described configuration is applied to a substrate and cured at room temperature.

  According to the present invention, a water / oil repellent coating film having excellent water / oil repellency and high hardness at room temperature can be formed.

  The water / oil repellent resin composition of the present invention comprises a polyol resin having a dimethylsiloxane group represented by the above formula (1) in the skeleton and having an alkoxy group and a hydroxyl group as a crosslinking group, and a hydrolyzable alkoxy Silane or its partial hydrolysis-condensation product and an organic acid are contained.

  As the polyol resin, a resin having a molecular structure having a dimethylsiloxane group represented by the above formula (1) as a graft chain in the molecular skeleton of the resin and an alkoxy group and a hydroxyl group as a crosslinking group is used.

  The dimethylsiloxane group is preferably contained in the polyol resin (including side chains) in the range of 10 to 90% by mass. If the content of dimethylsiloxane groups in the polyol resin is larger than this range, the adhesion of the coating film to the substrate tends to be reduced. Conversely, if the content is smaller than this range, the water and oil repellency is sufficient. There is a tendency not to develop. Since this dimethylsiloxane group is directly bonded to the molecular skeleton of the polyol resin, it does not easily fall off, and as a result, a coating film that stably maintains low surface free energy can be obtained over a long period of time. is there.

  Moreover, it is preferable that the alkoxy group is contained in the range of 1-30 mass% in polyol resin (a side chain is also included). If the content of alkoxy groups in the polyol resin is less than this range, the crosslinking density tends to be low and the coating film hardness tends to be low. Conversely, if the content is above this range, a hard coating can be obtained. Although it can, it tends to crack easily.

  As the alkoxy group, alkoxysilyl groups represented by structural formulas of the following formulas (2) to (4) are preferably used. When such an alkoxysilyl group is used, a resin composition excellent in crosslinkability can be obtained.

-(Si) (OR _a ) ₃ (2)
-(Si) (R _a ) (OR _b ) ₂ (3)
-(Si) (R _a ) ₂ (OR _b ) (4)

In the structural formulas of the above formulas (2) to (4), (R _a ) (R _b ) represents a hydrocarbon group, specifically, a methyl group, an ethyl group, a propyl group, a butyl group, Alkyl groups such as pentyl group, hexyl group, heptyl group, octyl group; cycloalkyl groups such as cyclopentyl group, cyclohexyl group; aralkyl groups such as 2-phenylethyl group, 2-phenylpropyl group, 3-phenylpropyl group; phenyl Group, aryl group such as tolyl group; alkenyl group such as vinyl group and allyl group; halogen-substituted hydrocarbon group such as chloromethyl group, γ-chloropropyl group, 3,3,3-trifluoropropyl group; γ-methacrylic group Examples of substituted hydrocarbon groups such as loxypropyl group, γ-glycidoxypropyl group, 3,4-epoxycyclohexylethyl group, γ-mercaptopropyl group, etc. It is possible.

  The hydroxyl value of the polyol resin is preferably in the range of 40 to 150 mgKOH / g, more preferably in the range of 60 to 120 mgKOH / g. When the hydroxyl value is lower than this range, the resulting coating film tends to have a reduced cross-linking density and a coating film with low hardness. Conversely, when the hydroxyl value is higher than this range, a hard coating film can be obtained, but the compatibility between the polyol resin and the solvent tends to be lowered, and the resin stability tends to be inferior.

  The polyol resin can contain a fluorine-containing group in the resin skeleton in order to enhance the durability of water repellency. Examples of the fluorine-containing group include fluoroalkylene groups of the following formulas (5) to (8), and a fluoroalkylene group can be introduced by bonding to a polyol resin skeleton during synthesis of a polyol resin. As the amount of the fluoroalkylene group increases, the durability of the water-repellent performance of the resulting coating film is improved, but the compatibility with the solvent and other resins used in the polyol resin tends to decrease. . For this reason, it is preferable to adjust content of a fluoroalkylene group in the range of 1-70 mass% in polyol resin (a side chain is included).

_{- (CF 2 -CF 2) -} (5)
_{- (CF 2 -CFH) - (} 6)
_{- (CF 2 -CH 2) -} (7)
_{- (CFH-CH 2) -} (8)

   As the polyol resin, those having a weight average molecular weight (Mw) of 20,000 to 400,000 are preferably used. If the molecular weight is higher than this range, the compatibility with the solvent and other crosslinking agents tends to be poor. Conversely, if the molecular weight is lower than this range, the physical properties of the resulting coating film tend to be reduced. The polyol resin is not limited as long as it has a plurality of hydroxyl groups, but a polyol resin having an acrylic resin as the main chain is preferably used.

  In a polyol resin, a hydroxyl group and an alkoxy group are cross-linking reaction sites, and are sites that react with alkoxysilane. In the method of Patent Document 2, which is a conventional technique, room temperature curability is obtained only with a hydroxyl group. However, in order to remove strong stains including oil-based inks, further crosslinkability is required. Here, for example, a dimethylsiloxane group-containing polyol resin having only a hydroxyl group as a crosslinking group does not exhibit sufficient water and oil repellency. However, in the present invention, the presence of an alkoxy group in the polyol resin adds not only a hydroxyl group-alkoxysilane-hydroxyl group crosslinking reaction but also a hydroxyl group-alkoxy group or an alkoxy group-alkoxy group crosslinking reaction, resulting in a high crosslinking density. In addition, high water and oil repellency can be realized.

  In the water / oil repellent resin composition of the present invention, the hydrolyzable alkoxysilane or the partially hydrolyzed condensate thereof is 20 to 100% by mass with respect to the solid content of the polyol resin (including side chains). It is contained to become. If the blending amount of the hydrolyzable alkoxysilane or its partially hydrolyzed condensate exceeds this range, a coating film having a high hardness can be obtained, but the coating film becomes too hard and too stiff so that the adhesion to the substrate is poor. Deteriorate. On the other hand, if the blending amount is less than this range, the coating film is insufficiently crosslinked and the hardness is lowered, and sufficient water and oil repellency cannot be obtained. For this reason, it is preferable to set the amount of alkoxysilane or the like in the above range.

  As the alkoxysilane monomer used for the hydrolyzable alkoxysilane or its partially hydrolyzed condensate, tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, or the like can be suitably used. In order to impart properties such as high strength to the coating film, it is preferable to use those obtained by polymerizing these monomers. As this oligomer material, ethyl silicate 40 (manufactured by Tama Chemical Co., Ltd., tetraethoxysilane pentamer) or methyl silicate 51 (manufactured by Mitsubishi Chemical Co., Ltd., tetramethoxysilane pentamer) can be used. Such oligomeric materials have hydrolyzability and may be mixed with the polyol resin as they are, but are diluted with an appropriate solvent, water as a curing agent and, if necessary, a catalyst (for example, hydrochloric acid, A necessary amount of nitric acid, acetic acid, etc.) is heated at 40 to 100 ° C., if necessary, and subjected to hydrolysis and polycondensation reaction to prepolymerize the alkoxysilane partial hydrolysis condensate. The alkoxysilane partial hydrolysis condensate may be prepared and mixed with a polyol resin. In that case, it is preferable to adjust so that the weight average molecular weight (Mw) of the alkoxysilane partial hydrolysis-condensation product (hydrolysis polycondensation product) obtained may be 900 or more, preferably 1000 or more in terms of polystyrene. If the molecular weight distribution (weight average molecular weight (Mw)) of the alkoxysilane partial hydrolyzed condensate is smaller than 900, curing shrinkage during condensation polymerization increases, and cracks tend to occur after the coating is cured. .

  The alkoxysilane partial hydrolysis-condensation product is a product in which a terminal alkoxy group is hydrolyzed during hydrolysis polycondensation to generate a silanol group (Si-OH). This silanol group is a hydroxyl group that is a cross-linking group of a polyol resin. By reacting, a structure of hydroxyl-alkoxysilane-hydroxyl is formed, and a hard and dense film can be formed. Thereby, a high crosslinking density and high water / oil repellency can be realized.

  In the water / oil repellent resin composition of the present invention, the organic acid is contained in an amount of 0.1 to 2.5% by mass based on the solid content of the resin component. The resin component is a component of a resin in which a polyol resin and an alkoxysilane (including a partially hydrolyzed condensate) are combined. If the amount of organic acid exceeds this range, curing shrinkage increases and adhesion to the substrate cannot be ensured. Conversely, if the amount of organic acid decreases below this range, crosslinking is insufficient. High water / oil repellency cannot be obtained.

Organic acids are used to promote the hydrolysis and polycondensation of hydrolyzable alkoxysilanes and the reaction between polyols and hydrolyzable alkoxysilanes, and a small amount of organic acid acts as a catalyst to cure. A crosslinked structure is formed. The organic acid is preferably a strong organic acid. Catalytic activity can be improved by showing strong acidity. The strong organic acid is an acid that produces a oxonium ion quantitatively because its proton transfer equilibrium is strongly biased toward the water side in the solution, and is preferably a strong organic acid having a pKa <1, and sulfonic acids (R -SO ₃ H), it can be used trifluoroacetic acid. Of these, sulfonic acids (R—SO ₃ H) are preferable. In this formula, examples of R include alkyl groups such as decane, octadecane, dodecane, and cyclohexyl; aryl groups such as benzene, p-toluene, and naphthalene; and fluorine-containing groups such as perfluoroalkyl groups. Specifically, sulfonic acids such as p-toluenesulfonic acid, benzenesulfonic acid, decanesulfonic acid, and perfluorosulfonic acid are preferably used.

  As the organic acid, for example, strong organic acids such as p-toluenesulfonic acid, benzenesulfonic acid, decanesulfonic acid, and perfluorosulfonic acid are preferably used. These organic acids have a strong catalytic action, and it is possible to obtain a highly crosslinked resin composition that cannot be obtained only by adding an inorganic acid for the polymerization of the alkoxysilane.

  The water / oil repellent resin composition of the present invention has room temperature curability. A water- and oil-repellent coating film can be easily formed on a substrate that cannot be heated or hard to be heated by having room temperature curability. Here, the normal temperature means a range (JIS Z 8703) in the range of 20 ° C. ± 15 ° C. (that is, 5 to 35 ° C.). Moreover, the room temperature curability is exhibited at normal pressure (1 atm, 101.3 kPa). In addition, as long as it has normal temperature sclerosis | hardenability, the temperature at the time of coating-film hardening may be normal temperature, or heating temperature (baking temperature) may be sufficient as it.

  The coated article of the present invention is obtained by applying the above water- and oil-repellent resin composition to a substrate and curing it at room temperature to form a coating film. The above water / oil repellent resin composition can be applied to a base material and heated (baked) to be cured, but in that case, a base material that cannot be heated from the standpoint of material, structure, etc. The problem of being unable to paint arises. However, since the water / oil repellent resin composition can be cured even under heating conditions, it also has a property of curing at room temperature, so that it is difficult to use a substrate or heating conditions that cannot be heated. A water- and oil-repellent coating film can be easily formed on a simple substrate.

  When forming a coating film with a water- and oil-repellent resin composition, a solvent may be added to the mixture of the above components to dilute it to form a paint, or when the mixture of the above components is liquid, You may use as it is, without adding etc. as it is. As the solvent, it is preferable to use a volatile solvent at room temperature, for example, lower aliphatic alcohols such as methanol, ethanol, isopropanol, normal butanol, isobutanol; ethylene glycol, ethylene glycol monobutyl ether, ethylene glycol monoacetate Examples include ethylene glycol derivatives such as ethyl ether; diethylene glycol derivatives such as diethylene glycol and diethylene glycol monobutyl ether; and diacetone alcohol. One or more selected from the group consisting of these can be used. In combination with these hydrophilic organic solvents, toluene, xylene, ethyl acetate, butyl acetate, methyl ethyl ketone, methyl isobutyl ketone, methyl ethyl ketoxime, and the like can also be used.

  The substrate is not particularly limited, and any material can be used. However, as a particularly preferable substrate to be applied, metals such as stainless steel, aluminum, galvanized steel sheet, iron, tile, enamel, etc. Examples thereof include ceramic and glass. These base materials retain hydroxyl groups due to oxides on the surface, and the silanol groups in the silicate hydrolyzate contained in the water- and oil-repellent resin composition as described above react with these hydroxyl groups. It is possible to form a coating film firmly adhered to the material.

  Furthermore, since the water / oil repellent resin composition of the present invention can be cured even at room temperature, it can be applied to plastics having lower heat resistance compared to glass and metal. Scratch prevention effect and the like can be obtained.

  Although it does not specifically limit as a plastic base material, For example, polycarbonate resin, an acrylic resin, ABS resin, a vinyl chloride resin, an epoxy resin, a phenolic resin etc. thermosetting or thermoplastic plastics, and these plastics are nylon fiber And fiber reinforced plastic (FRP) reinforced with organic fibers such as glass fiber and the like.

  The method of applying the water / oil repellent resin composition to the substrate is not particularly limited, and is a spray coating method, a dip coating method, a flow coating method, a spin coating method, a roll coating method, a brush coating, a sponge. A method such as painting can be suitably used. Moreover, it is not limited only to the method of coating and applying, it is molded into a sheet and laminated on the base material, or it is sprayed onto a mold and transferred to the base material for lamination, or a nonwoven fabric, etc. There is a method of impregnating and coating with a base material with a press or the like.

  The curing method is not particularly limited, and may be cured in a heat drying oven or at room temperature. If it is cured at room temperature, depending on the desired cured film performance, the heat resistant temperature and productivity of the substrate, it can be left at room temperature, left at a low temperature of about 10 ° C, or left at a temperature of about 30 ° C. can do. Since the water / oil repellent resin composition of the present invention can be cured at room temperature, it can be applied not only in the process of coating an object to be coated at a coating factory, but also at the site where the coated product is used. Moreover, there is no restriction | limiting in particular also about the film thickness of a coating film, Usually, it can set to about 0.1 micrometer-50 micrometers.

  The present invention will be described below with reference to examples. Unless otherwise specified, parts represent parts by mass, and% represents mass%.

Example 1
(Synthesis of alkoxysilane hydrolyzate)
Take 3.1 parts by mass of methyl silicate 51 (Mitsubishi Chemical Co., Ltd.), which is an oligomer of tetramethoxy silane, and add 95 parts by mass of methyl alcohol to this. An alkoxysilane hydrolyzate solution was prepared by dropping and heating the solution to 60 ° C. over 1 hour. The hydrolyzate solution had a solid content (resin component) of 1.6% by mass.

(Preparation of paint and painted plate)
140 parts by mass of the above alkoxysilane hydrolyzate, polyol resin “ZX-022H” having a dimethylsiloxane group in the skeleton and an alkoxy group and a hydroxyl group as a crosslinking group (Fuji Kasei Kogyo Co., Ltd .: solid content 45 %) 10 parts by mass, 5 parts by mass of a 1% isopropanol solution of p-toluenesulfonic acid monohydrate (manufactured by Nacalai Tesque) was added, and the mixture was stirred for 5 minutes to prepare a paint. . This paint contains about 50% by mass of an alkoxysilane hydrolyzate based on the solid content of the polyol resin, and an organic acid based on the total solid content of the polyol resin and the alkoxysilane hydrolyzate. About 0.74 mass%.

  Next, a slide glass (S9111 made by Matsunami Glass) was used as a base material, and a paint was applied to the base material by spray coating so that the coating film thickness after drying was 0.5 μm. The coating film was hardened by leaving still for days, and the coating board of this invention was obtained.

(Example 2)
The same paint as in Example 1 was used. And, using a slide glass (S9111 made by Matsunami Glass) as a base material, a paint is applied by spray coating so that the coating film thickness after drying becomes 0.5 μm, and at 100 ° C. for 20 minutes. The coated film of the present invention was obtained by curing by heating.

(Example 3)
Polyol resin “ZX-022H” having 60 parts by mass of the alkoxysilane hydrolyzed solution shown in Example 1 and a dimethylsiloxane group in the skeleton and having an alkoxy group and a hydroxyl group as a crosslinking group (manufactured by Fuji Kasei Kogyo Co., Ltd .: solid Min. 45%) is mixed with 10 parts by mass, and 4 parts by mass of 1% isopropanol solution of p-toluenesulfonic acid monohydrate (manufactured by Nacalai Tesque) is added and stirred for 5 minutes to mix. Produced. This paint contains about 21% by mass of an alkoxysilane hydrolyzate based on the solid content of the polyol resin, and an organic acid based on the total solid content of the polyol resin and the alkoxysilane hydrolyzate. About 0.73 mass%.

  A slide glass (S9111 made by Matsunami Glass) is used as the base material, and the paint is applied to the base material by spray coating so that the coating film thickness after drying is 0.5 μm, and left at room temperature for 3 days. By doing so, the coating film was hardened and the coating board of this invention was obtained.

Example 4
Polyol resin “ZX-022H” having 270 parts by mass of an alkoxysilane hydrolyzed solution shown in Example 1 and a dimethylsiloxane group in the skeleton and having an alkoxy group and a hydroxyl group as a crosslinking group (manufactured by Fuji Kasei Kogyo Co., Ltd .: solid Min. 45%) is mixed with 10 parts by mass, and further 6 parts by mass of 1% isopropanol solution of p-toluenesulfonic acid monohydrate (manufactured by Nacalai Tesque) is added and stirred for 5 minutes to mix. Produced. This paint contains about 96% by mass of an alkoxysilane hydrolyzate based on the solid content of the polyol resin, and an organic acid based on the total solid content of the polyol resin and the alkoxysilane hydrolyzate. About 0.68 mass%.

  A slide glass (S9111 made by Matsunami Glass) is used as the base material, and the paint is applied to the base material by spray coating so that the coating film thickness after drying is 0.5 μm, and left at room temperature for 3 days. By doing so, the coating film was hardened and the coating board of this invention was obtained.

(Example 5)
Polyol resin “ZX-022H” having 140 parts by mass of the alkoxysilane hydrolyzed solution shown in Example 1 and a dimethylsiloxane group in the skeleton and having an alkoxy group and a hydroxyl group as a crosslinking group (manufactured by Fuji Kasei Kogyo Co., Ltd .: solid Min. 45%) is mixed with 10 parts by mass, and 1 part by mass of 1% isopropanol solution of p-toluenesulfonic acid monohydrate (manufactured by Nacalai Tesque) is added and stirred for 5 minutes to mix. Produced. This paint contains about 50% by mass of an alkoxysilane hydrolyzate based on the solid content of the polyol resin, and an organic acid based on the total solid content of the polyol resin and the alkoxysilane hydrolyzate. About 0.15 mass%.

  A slide glass (S9111 made by Matsunami Glass) is used as the base material, and the paint is applied to the base material by spray coating so that the coating film thickness after drying is 0.5 μm, and left at room temperature for 3 days. By doing so, the coating film was hardened and the coating board of this invention was obtained.

(Example 6)
Polyol resin “ZX-022H” having 140 parts by mass of the alkoxysilane hydrolyzed solution shown in Example 1 and a dimethylsiloxane group in the skeleton and having an alkoxy group and a hydroxyl group as a crosslinking group (manufactured by Fuji Kasei Kogyo Co., Ltd .: solid Min. 45%) is mixed with 10 parts by mass, and further 15 parts by mass of 1% isopropanol solution of p-toluenesulfonic acid monohydrate (manufactured by Nacalai Tesque) is added and stirred for 5 minutes to mix. Produced. This paint contains about 50% by mass of an alkoxysilane hydrolyzate based on the solid content of the polyol resin, and an organic acid based on the total solid content of the polyol resin and the alkoxysilane hydrolyzate. About 2.2% by mass.

  A slide glass (S9111 made by Matsunami Glass) is used as the base material, and the paint is applied to the base material by spray coating so that the coating film thickness after drying is 0.5 μm, and left at room temperature for 3 days. By doing so, the coating film was hardened and the coating board of this invention was obtained.

(Example 7)
A polyol resin “ZX-022H” having 140 parts by mass of the alkoxysilane hydrolyzed solution shown in Example 1 and having a dimethylsiloxane group in the skeleton and having an alkoxy group and a hydroxyl group as a crosslinking group (manufactured by Fuji Kasei Kogyo Co., Ltd .: (Solid content: 45%) 10 parts by mass, and further, 0.125 parts by mass of dodecylbenzenesulfonic acid IPA dissolved product “CAT6000” (Mitsui Chemicals Co., Ltd .: solid content: 40%) was added and stirred for 5 minutes. The paint was prepared by mixing. This paint contains about 50% by mass of an alkoxysilane hydrolyzate based on the solid content of the polyol resin, and an organic acid based on the total solid content of the polyol resin and the alkoxysilane hydrolyzate. About 0.74 mass%.

  A slide glass (S9111 made by Matsunami Glass) is used as the base material, and the paint is applied to the base material by spray coating so that the coating film thickness after drying is 0.5 μm, and left at room temperature for 3 days. By doing so, the coating film was hardened and the coating board of this invention was obtained.

(Comparative Example 1)
140 parts by mass of the alkoxysilane hydrolyzed solution described in Example 1 and a polyol resin “ZX-022H” having a dimethylsiloxane group in the skeleton and having an alkoxy group and a hydroxyl group as a crosslinking group (manufactured by Fuji Kasei Kogyo Co., Ltd.) : 45% solid content) and 10 parts by mass were mixed and stirred for 5 minutes to prepare a paint.

  Next, a slide glass (S9111 made by Matsunami Glass) was used as a base material, and a paint was applied to the base material by spray coating so that the coating film thickness after drying was 0.5 μm. The coated film was cured by allowing to stand for days to obtain a coated plate.

(Comparative Example 2)
The same paint as in Comparative Example 1 was used. And, using a slide glass (S9111 made by Matsunami Glass) as a base material, a paint is applied by spray coating so that the coating film thickness after drying becomes 0.5 μm, and at 100 ° C. for 20 minutes. The coated film was obtained by heating to obtain a coated plate.

(Comparative Example 3)
400 parts by mass of polyol resin “Efclear KD-270” (manufactured by Kanto Denka Kogyo) having a dimethylsiloxane chain in the skeleton and having only a hydroxyl group as a crosslinking group, 100 parts by mass of methyl silicate 51 (manufactured by Colcoat), n -300 parts by weight of butanol were mixed, and 5 parts by weight of 1% isopropanol solution of p-toluenesulfonic acid monohydrate (manufactured by Nacalai Tesque) was added and stirred for 5 minutes to mix to prepare a paint. .

  Next, using a slide glass (S9111 made by Matsunami Glass) as a base material, a paint is applied by spray coating so that the coating film thickness after drying becomes 1 μm, and heated at 100 ° C. for 20 minutes. A painted plate was obtained.

(Comparative Example 4)
350 parts by mass of the alkoxysilane hydrolyzed solution described in Example 1, a polyol resin “ZX-022H” having a dimethylsiloxane group in the skeleton and having an alkoxy group and a hydroxyl group as a crosslinking group (manufactured by Fuji Kasei Kogyo Co., Ltd.) : 45% solid content) and 10 parts by mass, 5 parts by mass of 1% isopropanol solution of p-toluenesulfonic acid monohydrate (manufactured by Nacalai Tesque) was added and stirred for 5 minutes to mix. A paint was made. This paint contains about 124% by mass of an alkoxysilane hydrolyzate based on the solid content of the polyol resin.

  Next, a slide glass (S9111 made by Matsunami Glass) was used as a base material, and a paint was applied to the base material by spray coating so that the coating film thickness after drying was 0.5 μm. Heated for a minute to obtain a painted plate.

(Comparative Example 5)
Polyol resin “ZX-022H” (manufactured by Fuji Kasei Kogyo Co., Ltd.) having 30 parts by mass of the alkoxysilane hydrolyzed solution described in Example 1 and having a dimethylsiloxane group in the skeleton and having an alkoxy group and a hydroxyl group as a crosslinking group. : 45% solid content) and 10 parts by mass, 5 parts by mass of 1% isopropanol solution of p-toluenesulfonic acid monohydrate (manufactured by Nacalai Tesque) was added and stirred for 5 minutes to mix. A paint was made. This paint contains about 10.7% by mass of an alkoxysilane hydrolyzate based on the solid content of the polyol resin.

  Next, using a slide glass (S9111 made by Matsunami Glass) as a base material, a paint is applied by spray coating so that the coating film thickness after drying becomes 1 μm, and heated at 100 ° C. for 20 minutes. A painted plate was obtained.

(Comparative Example 6)
140 parts by mass of the alkoxysilane hydrolyzed solution described in Example 1 and a polyol resin “ZX-022H” having a dimethylsiloxane group in the skeleton and having an alkoxy group and a hydroxyl group as a crosslinking group (manufactured by Fuji Kasei Kogyo Co., Ltd.) : 45% solid content) and 10 parts by mass, and 30 parts by mass of 1% isopropanol solution of p-toluenesulfonic acid monohydrate (manufactured by Nacalai Tesque) was added and stirred for 5 minutes. A paint was made. This paint contains about 50% by mass of an alkoxysilane hydrolyzate based on the solid content of the polyol resin, and an organic acid based on the total solid content of the polyol resin and the alkoxysilane hydrolyzate. About 4.46 mass%.

  Next, a slide glass (S9111 made by Matsunami Glass) was used as a base material, and a paint was applied to the base material by spray coating so that the coating film thickness after drying was 0.5 μm. Heated for a minute to obtain a painted plate.

(Comparative Example 7)
Fluoropolyol resin “Lumiflon LF-200” (manufactured by Asahi Glass Co., Ltd.) having no dimethylsiloxane chain and having only a hydroxyl group as a crosslinking group, 100 parts by mass of methyl silicate 51 (manufactured by Colcoat), and 300 parts by mass of n-butanol 5 parts by weight of 1% isopropanol solution of p-toluenesulfonic acid monohydrate (manufactured by Nacalai Tesque) was added and stirred for 5 minutes to prepare a paint.

  Next, using a slide glass (S9111 made by Matsunami Glass) as a base material, a paint is applied by spray coating so that the coating film thickness after drying becomes 1 μm, and heated at 100 ° C. for 20 minutes. A painted plate was obtained.

(Evaluation)
About the coating film produced in said Examples 1-7 and Comparative Examples 1-7, the following item was evaluated.

(1) Film forming property The appearance of the coating film was evaluated when the film was formed with the predetermined film thickness described in Examples and Comparative Examples. The judgment criteria were “◯” if “a transparent continuous film without cracks, twists, cracks, etc. can be produced”, and “x” if “any one of them is not satisfied”.

(2) Hot water adhesion After being immersed in tap water kept at 80 ° C. for 24 hours in a 20 L stainless steel container, it was cut with 11 cutter knives vertically and horizontally at intervals of 1 mm, and serotape (registered trademark) ) Was adhered and peeled, and the number of grids on which the coating film remained was measured (cross grid adhesion test). As judgment criteria, “100/100” (no peeling) was “◯”, and “0-99 / 100” (one or more peeling) was “x”.

(3) Water repellency (water contact angle)
The contact angle of the ion-exchanged water was measured with a contact angle measuring device (manufactured by Kyowa Interface Science Co., Ltd., model: DM500), and used as an index of water repellency.

(4) Pencil hardness The hardness of the coating film surface was measured according to JIS K-5600-5-4.

(5) Oil repellency (initial transmittance, transmittance after adhesion of oil-based ink)
The transmittance of light having a wavelength of 555 nm was measured with a spectrophotometer (U-4100 manufactured by Hitachi High-Tech) to obtain the initial transmittance.

  After drawing a line on the surface of the coating with an oil-based ink marker (Zebra's “Himacky (registered trademark)” black thick) and measuring the transmittance of light having a wavelength of 555 nm as in the initial case, the oil-based ink It was set as the transmittance after adhesion.

  Regarding the criterion for determining the transmittance, 80% or more is “◯”, 10% or more but less than 80% is “Δ”, and less than 10% is “x”.

  The results are shown in Table 1. It can be seen from Table 1 that the water / oil repellent resin compositions of the examples are excellent in film-forming properties, adhesion, water / oil repellency and hardness.

Claims (2)

A polyol resin having a dimethylsiloxane group represented by the formula (1) in the skeleton and having an alkoxy group and a hydroxyl group as a crosslinking group, and a hydrolyzability of 20 to 100% by mass based on the solid content of the polyol resin 0.1 to 2.5% by mass with respect to the solid content of the resin component obtained by combining the alkoxysilane or the partially hydrolyzed condensate thereof and the polyol resin and the hydrolyzable alkoxysilane or the partially hydrolyzed condensate thereof. A water / oil repellent resin composition comprising an organic acid and having room temperature curability.

  A coated product obtained by applying the water- and oil-repellent resin composition according to claim 1 to a substrate and curing it at room temperature.