WO2018230120A1 - Coating composition and hydrophilic member - Google Patents

Abstract

This coating composition comprises a (meth)acrylate monomer with five or more functional groups having a carbon-carbon unsaturated bond, a surfactant, a porous substance 22, and a dispersing solvent for dispersing the (meth)acrylate monomer, the surfactant, and the porous substance. The hydrophilic member 100 comprises a base material 10, and a hydrophilic film 20 formed from the coating composition, provided on the base material.

Description

Coating composition and hydrophilic member

The present invention relates to a coating composition and a hydrophilic member. Specifically, the present invention relates to a coating composition capable of imparting antifouling properties against oil and a hydrophilic member provided with a hydrophilic film obtained from the coating composition.

In a house member, a material that can easily remove oil is used if it is easy to adhere to oil, such as a kitchen member. As such a material that easily removes oil, an inorganic material such as tile, a hydrophilic material such as glass, or a water- and oil-repellent material typified by Teflon (registered trademark) is used.

Also, hydrophilic coating is performed as a surface treatment for kitchen members used in an environment where oil such as a range hood is likely to adhere (see, for example, Patent Document 1). Patent Document 1 discloses a range hood fan in which a hydrophilic baking paint is provided as a surface layer. As hydrophilic baking paints, for example, those having a composition in which an inorganic compound mainly composed of alumina, silica, magnesia or the like is bound with a metal compound composed of copper, zinc, silver or the like are disclosed. Furthermore, when a metal plate such as stainless steel is used as the base material, it is also disclosed that baking coating is performed at a baking temperature of about 180 to 220 ° C. to a thickness of about 20 to 40 μm. By applying such a hydrophilic coating, the oil stain can be floated using a large amount of water, and the oil stain can be easily removed.

JP 2000-199637 A

However, as in Patent Document 1, when a hydrophilic baking paint is used, it is necessary to use a material having high heat resistance such as metal or ceramics as a base material to be coated.

The present invention has been made in view of such problems of the conventional technology. An object of the present invention is to provide a coating composition capable of imparting high hydrophilicity without limiting the type of base material and enhancing antifouling properties against oil, and a hydrophilic film obtained from the coating composition It is providing the hydrophilic member provided with.

In order to solve the above problems, the coating composition according to the first aspect of the present invention includes a (meth) acrylate monomer having a functional group having a carbon-carbon unsaturated bond of 5 or more, a surfactant, A porous material, a (meth) acrylate monomer, a surfactant, and a dispersion solvent for dispersing the porous material are included.

The hydrophilic member according to the second aspect of the present invention includes a base material and a hydrophilic film provided on the base material and formed from a coating composition.

FIG. 1 is a cross-sectional view schematically showing a hydrophilic member according to an embodiment of the present invention.

Hereinafter, the coating composition according to the present embodiment and the hydrophilic member including the hydrophilic film obtained from the coating composition will be described in detail. In addition, the dimension ratio of drawing is exaggerated on account of description, and may differ from an actual ratio.

部 材 For materials that easily adhere to oil, such as kitchen components, hydrophilic materials with hydrophilic properties on the surface are used so that the oil can be easily removed. Thus, by imparting hydrophilicity to the surface of the member, water can easily enter between the surface of the member and the oil even when oil is attached. Therefore, the oil component can be lifted simply by immersing the member in water, so that the oil component can be easily removed.

And, as a result of intensive studies on a method for imparting hydrophilicity to the surface of the member, the present inventor has found that hydrophilicity can be imparted by adding a small amount of a porous substance such as zeolite to the base resin. However, when an ultraviolet curable resin is used as the base resin, if the amount of the porous material added is increased to increase hydrophilicity, ultraviolet rays may not be irradiated to the deep part of the resin. That is, since the ultraviolet ray is absorbed or reflected by the porous material, the ultraviolet ray may not reach the deep part of the resin. In that case, it is difficult to sufficiently cure the ultraviolet curable resin. In addition, when the amount of the porous material added is simply increased so as to increase the hydrophilicity, it becomes difficult to uniformly disperse the porous material.

Here, for example, in Japanese Patent Laid-Open No. 61-181872, a radiation curing coating is disclosed. This radiation-curing coating material is a heavy polymer having a molecular weight of 2,000 to 100,000 by binding structural units having a predetermined functional group via any one of urethane bonds, urea bonds, N-substituted urea bonds, amide bonds, and ester bonds. It contains a coalescence. It is described that the radiation curing coating may further contain carbon black. It is also disclosed that an electron beam is preferable as the radiation used for crosslinking and curing the radiation curing coating. However, when such carbon black is contained, since the electron beam may not reach the deep part of the resin, it may be difficult to sufficiently cure the resin.

The coating composition of the present embodiment can be easily cured even when a porous material is added, and can obtain a film capable of imparting high hydrophilicity.

[Coating composition]
The coating composition which concerns on this embodiment can obtain the hydrophilic film with which antifouling property with respect to an oil lasts by apply | coating to a base material and making it harden | cure. The coating composition comprises a (meth) acrylate monomer that serves as a base resin for the obtained hydrophilic film, a porous material for imparting hydrophilicity to the hydrophilic film, and a surface activity for dispersing the porous material. Containing the agent.

((Meth) acrylate monomer)
The coating composition of this embodiment contains a (meth) acrylate monomer having 5 or more functional groups having a carbon-carbon unsaturated bond. Such a polyfunctional (meth) acrylate monomer has high reactivity with free radicals or ions generated from the polymerization initiator described later, and the crosslinking reaction easily proceeds. Therefore, even when an active energy ray such as ultraviolet rays is absorbed or reflected by adding a porous substance, the crosslinking reaction of (meth) acrylate monomers proceeds, so that the resulting hydrophilic film can be easily cured. Is possible. Moreover, since the crosslinking density of the hydrophilic film obtained by using a polyfunctional (meth) acrylate monomer increases, the hardness of the hydrophilic film can also be improved. In the present specification, the “(meth) acrylate monomer” includes an acrylate monomer and a methacrylate monomer. The “functional group having a carbon-carbon unsaturated bond” includes an acryloyl group and a methacryloyl group.

As the polyfunctional (meth) acrylate monomer, it is preferable to use a (meth) acrylate monomer having 5 or more functional groups having a carbon-carbon unsaturated bond. Examples of such a polyfunctional (meth) acrylate monomer include at least one of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate.

In the coating composition of the present embodiment, only a (meth) acrylate monomer having 5 or more functional groups having a carbon-carbon unsaturated bond may be used as the (meth) acrylate monomer. Moreover, since the crosslinking density of the hydrophilic film obtained by using a polyfunctional (meth) acrylate monomer increases, the hardness of the hydrophilic film can also be improved. However, when the crosslink density is excessively increased, the hydrophilic film tends to decrease in elongation and may be peeled off.

Therefore, the coating composition of the present embodiment includes a monofunctional (meth) acrylate monomer, a bifunctional (meth) acrylate monomer, a trifunctional (meth) acrylate monomer, and a tetrafunctional in addition to a pentafunctional or higher functional (meth) acrylate monomer. It is preferable to include at least one selected from the group consisting of (meth) acrylate monomers. By including such a (meth) acrylate monomer having 1 to 4 functional groups having a carbon-carbon unsaturated bond, it is possible to suppress an excessive increase in the crosslinking density of the resulting hydrophilic film. Therefore, the elongation is improved in addition to the hardness of the hydrophilic film, and as a result, the peeling of the hydrophilic film can be suppressed.

The monofunctional (meth) acrylate monomer, bifunctional (meth) acrylate monomer, trifunctional (meth) acrylate monomer, and tetrafunctional (meth) acrylate monomer that can be added to the coating composition are not particularly limited. Monofunctional acrylate monomers include ethoxylated o-phenylphenol acrylate, methoxypolyethylene glycol # 400 acrylate, methoxypolyethylene glycol # 550 acrylate, phenoxypolyethylene glycol acrylate, 2-acryloyloxyethyl succinate manufactured by Shin-Nakamura Chemical Co., Ltd. Mention may be made of isostearyl acrylate. Examples of the monofunctional acrylate monomer include β-carboxyethyl acrylate, isobornyl acrylate, octyl / decyl acrylate, ethoxylated phenyl acrylate (EO 2 mol), and ethoxylated phenyl acrylate (EO 1 mol) manufactured by Daicel Ornex Co., Ltd. Can do.

Examples of the bifunctional acrylate monomer include 2-hydroxy-3-acryloyloxypropyl methacrylate, polyethylene glycol # 200 diacrylate, polyethylene glycol # 400 diacrylate, polyethylene glycol # 600 diacrylate, polyethylene glycol manufactured by Shin-Nakamura Chemical Co., Ltd. # 1000 diacrylate, propoxylated ethoxylated bisphenol A diacrylate, ethoxylated bisphenol A diacrylate, 9,9-bis [4- (2-acryloyloxyethoxy) phenyl] fluorene, propoxylated bisphenol A diacrylate, tricyclode Candimethanol diacrylate, 1,10-decanediol diacrylate, 1,6-hexanediol diacrylate, 1,9-nonandio Diacrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate, polypropylene glycol ♯400 diacrylate, polypropylene glycol ♯700 diacrylate, can be mentioned polytetramethylene glycol ♯650 diacrylate. Examples of the bifunctional acrylate monomer include dipropylene glycol diacrylate, 1,6-hexanediol diacrylate, tripropylene glycol diacrylate, PO-modified neopentyl glycol diacrylate, and modified bisphenol A diacrylate manufactured by Daicel Ornex Co., Ltd. , Tricyclodecane dimethanol diacrylate, PEG 400 diacrylate, PEG 600 diacrylate, neopentyl glycol hydroxypivalate ester diacrylate.

Examples of the trifunctional acrylate monomer and tetrafunctional acrylate monomer include ethoxylated isocyanuric acid triacrylate, ε-caprolactone-modified tris- (2-acryloxyethyl) isocyanurate, Ethoxylated glycerine triacrylate (EO9mol), manufactured by Shin-Nakamura Chemical Co., Ltd. Ethoxylated glycerine triacrylate (EO20mol), pentaerythritol triacrylate (37% triester), pentaerythritol triacrylate (55% triester), pentaerythritol triacrylate (57% triester), trimethylolpropane triacrylate, ditrimethylolpropane tetraacrylate Examples thereof include acrylate, ethoxylated pentaerythritol tetraacrylate, and pentaerythritol tetraacrylate.

Examples of trifunctional acrylate monomers include pentaerythritol (tri / tetra) acrylate, trimethylolpropane triacrylate, trimethylolpropane ethoxytriacrylate, trimethylolpropane propoxytriacrylate, and glycerin propoxytriacrylate manufactured by Daicel Ornex Co., Ltd. Can do. Examples of the tetrafunctional acrylate monomer include pentaerythritol ethoxytetraacrylate, ditrimethylolpropane tetraacrylate, and pentaerythritol (tri / tetra) acrylate manufactured by Daicel Ornex Co., Ltd.

Examples of monofunctional methacrylate monomers include 2-methacryloyloxyethyl phthalic acid, methoxypolyethylene glycol # 400 methacrylate, methoxypolyethylene glycol # 1000 methacrylate, phenoxyethylene glycol methacrylate, stearyl methacrylate, 2-methacryloyloxy manufactured by Shin-Nakamura Chemical Co., Ltd. Mention may be made of ethyl succinate.

Examples of the bifunctional methacrylate monomer include ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, polyethylene glycol # 200 dimethacrylate, polyethylene glycol # 400 dimethacrylate, polyethylene glycol # 600 dimethacrylate manufactured by Shin-Nakamura Chemical Co., Ltd. Polyethylene glycol # 1000 dimethacrylate, ethoxylated bisphenol A dimethacrylate, tricyclodecane dimethanol dimethacrylate, 1,10-decanediol dimethacrylate, 1,6-hexanediol dimethacrylate, 1,9-nonanediol dimethacrylate, Neopentyl glycol dimethacrylate, ethoxylated polypropylene glycol # 7 0 dimethacrylate, glycerol dimethacrylate, and polypropylene glycol ♯400 dimethacrylate.

Examples of the trifunctional methacrylate monomer include trimethylolpropane trimethacrylate manufactured by Shin-Nakamura Chemical Co., Ltd.

It is preferable that at least one of the (meth) acrylate monomer having 5 or more functional groups and the (meth) acrylate monomer having 4 or less functional groups has a hydroxyl group in the molecule. Even when the (meth) acrylate monomer is polymerized to form a hydrophilic film, it is more preferable that the hydroxyl group remains in the hydrophilic film. When the base resin (acrylic resin) constituting the hydrophilic film has a hydroxyl group, the base resin itself has a high affinity for water. Therefore, even when the content of the porous material is reduced, the hydrophilicity of the hydrophilic film surface can be improved.

In the coating composition, the content ratio of the (meth) acrylate monomer having 5 or more functional groups and the (meth) acrylate monomer having 4 or less functional groups is not particularly limited. The ratio of the (meth) acrylate monomer having 5 or more functional groups to the (meth) acrylate monomer having 4 or less functional groups is preferably 90:10 to 10:90 by mass ratio. The ratio of the (meth) acrylate monomer having 5 or more functional groups and the (meth) acrylate monomer having 4 or less functional groups is more preferably 80:20 to 20:80 in terms of mass ratio. By having such a content ratio, it is possible to improve the hardness and elongation of the obtained hydrophilic film and to further suppress peeling.

(Porous material)
The coating composition according to the present embodiment contains a porous substance in order to impart hydrophilicity to the obtained hydrophilic film. Since the porous material has a plurality of pores, the specific surface area is large, and water molecules are easily adsorbed on the surface and inside of the porous material. Therefore, when the hydrophilic film contains a porous substance, moisture is easily adsorbed on the surface of the hydrophilic film, so that the hydrophilicity can be improved.

As the porous substance, a substance having a plurality of pores and capable of adsorbing water molecules can be used. As the porous material, it is preferable to use at least one selected from the group consisting of zeolite, carbon particles, and clay particles. The zeolite is not particularly limited, but for example, at least one selected from the group consisting of A-type, Analsim, ZSM-5, MCM-22, X-type, Y-type, mordenite, beta, globalite, and VPI-5 should be used. Can do. As the carbon particles, at least one selected from the group consisting of graphene, carbon black, carbon molecular sieve, and carbon nanotube can be used. As the clay particles, montmorillonite is preferably used. For example, bentonite mainly composed of montmorillonite can be used.

When using zeolite as the porous material, the average pore diameter of the zeolite is preferably 13 mm or less, and more preferably 5 mm or less. When the average pore diameter of the zeolite is 13 mm or less, the amount of water molecules adsorbed increases, so that the hydrophilicity of the obtained hydrophilic membrane can be improved. The average pore diameter of zeolite can be determined by a nitrogen gas adsorption method.

In the coating composition, the porous material is preferably zeolite. The porous material is preferably carbon particles. Zeolite and carbon particles have a large number of pores and are highly adsorbable with water molecules. Therefore, it is possible to further improve the hydrophilicity of the obtained hydrophilic film.

In the coating composition, the content of the porous material relative to the (meth) acrylate monomer ([porous material] / [(meth) acrylate monomer]) is preferably 1 to 30% by mass. That is, when the (meth) acrylate monomer is only a pentafunctional or higher (meth) acrylate monomer, the content of the porous material relative to the pentafunctional or higher (meth) acrylate monomer may be 1 to 30% by mass. preferable. When the (meth) acrylate monomer is a mixture of a pentafunctional or higher (meth) acrylate monomer and a tetrafunctional or lower (meth) acrylate monomer, the content of the porous material in the mixture is 1 to 30. It is preferable that it is mass%. When the content of the porous material is 1 to 30% by mass, the porous material is highly dispersed in the obtained hydrophilic film, so that water molecules can be efficiently adsorbed to increase the hydrophilicity.

In addition, the upper limit of the content of the porous substance with respect to the (meth) acrylate monomer is more preferably 20% by mass, further preferably 15% by mass, and particularly preferably 10% by mass. Further, the lower limit of the content of the porous material relative to the (meth) acrylate monomer is more preferably 1% by mass, and further preferably 3% by mass.

(Surfactant)
The coating composition of this embodiment contains a surfactant in order to disperse the porous material. The surfactant is not particularly limited as long as the porous material can be dispersed in the liquid coating composition. As the surfactant, at least one selected from the group consisting of an anionic surfactant, a cationic surfactant, a nonionic surfactant and an amphoteric surfactant can be used. Among these, it is preferable to use an anionic surfactant as the surfactant. As the anionic surfactant, at least one selected from the group consisting of a carboxylic acid type, a sulfonic acid type, a sulfate ester type, and a phosphate ester type can be used.

In the coating composition, the surfactant is preferably a copolymer having an acidic group in the molecule. By using such a copolymer, the porous material is highly dispersed inside the (meth) acrylate monomer, and the hydrophilicity of the hydrophilic film can be further increased. In addition, as an acidic group, at least one chosen from the group which consists of a carboxy group, a sulfo group, and a phosphoric acid group can be used.

(Dispersion solvent)
When mixing the (meth) acrylate monomer, the surfactant, and the porous material, it is preferable to add a dispersion solvent to the coating composition and adjust the viscosity so that it can be easily applied. As the dispersion solvent for adjusting the viscosity, at least one of water and an organic solvent can be used. The organic solvent is not particularly limited, but it is preferable to appropriately select an organic solvent that volatilizes easily when a coating film is formed and that does not cause curing inhibition when forming a hydrophilic film. Examples of the organic solvent include aromatic hydrocarbons (such as toluene and xylene), alcohols (such as methanol, ethanol, and isopropyl alcohol), and ketones (such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone). Further examples include aliphatic hydrocarbons (such as hexane and heptane), ethers (such as tetrahydrofuran), amide solvents (such as N, N-dimethylformamide (DMF) and dimethylacetamide (DMAc)), methyl acetate, and butyl acetate. It is done. These organic solvents may be used individually by 1 type, and may be used in combination of 2 or more type.

(Polymerization initiator)
The coating composition of this embodiment preferably contains a polymerization initiator for accelerating the polymerization reaction of the (meth) acrylate monomer having a carbon-carbon unsaturated bond. As the polymerization initiator, at least one of a photopolymerization initiator and a thermal polymerization initiator can be used, but it is preferable to use a photopolymerization initiator. By using the photopolymerization initiator, the (meth) acrylate monomer is instantaneously cured by irradiating the active energy ray, so that the production process can be shortened.

A photopolymerization initiator is a compound having a function of initiating a polymerization reaction of a (meth) acrylate monomer, and is a substance that absorbs light of a specific wavelength from an active energy ray to be excited to generate radicals and ions. As such a photopolymerization initiator, for example, at least one selected from the group consisting of benzoin ether series, ketal series, acetophenone series, benzophenone series, and thioxanthone series can be used.

The thermal polymerization initiator is a compound that has a function of initiating the polymerization reaction of the (meth) acrylate monomer, and is a substance that generates active species such as radicals and ions when heated. The thermal polymerization initiator is at least one selected from the group consisting of azo compounds such as 2,2′-azobis (isobutyronitrile), peroxides such as benzoyl peroxide, benzenesulfonic acid esters and alkylsulfonium salts. Can be used.

Next, a method for producing the coating composition of this embodiment will be described. The coating composition can be prepared by mixing the above-described (meth) acrylate monomer, a porous substance, a surfactant and a dispersion solvent, and a polymerization initiator to be added as necessary. The mixing conditions are not particularly limited, and the mixing can be performed in the atmosphere at room temperature. Further, the order of mixing the (meth) acrylate monomer, the porous material, the surfactant, the dispersion solvent, and the polymerization initiator is not particularly limited.

Another method for producing a coating composition is to prepare an acrylate solution in which a (meth) acrylate monomer is dissolved and a porous material dispersion in which a porous material is dispersed, and then mix these solutions. preferable. Specifically, first, an acrylate solution is prepared by dissolving a (meth) acrylate monomer in a dispersion solvent. Moreover, a porous material dispersion is prepared by mixing a porous material, a surfactant, and a dispersion solvent. Then, the coating composition can be obtained by mixing the obtained acrylate solution and the porous material dispersion. In this way, the acrylate solution and the porous material dispersion are separately prepared and then mixed together, thereby suppressing the aggregation of the porous material and uniformly mixing the (meth) acrylate monomer and the porous material. Is possible.

The pH (hydrogen ion index) of the mixed solution obtained by mixing the (meth) acrylate monomer, the surfactant, the porous material, the dispersion solvent, and the polymerization initiator is not particularly limited. However, when the pH changes to acidic or alkaline, the porous material may aggregate and may not be highly dispersed inside the resulting hydrophilic film. Therefore, the pH of the mixed solution obtained by mixing the (meth) acrylate monomer, the surfactant, the porous material, the dispersion solvent, and the polymerization initiator is preferably 7 to 9, and preferably 7.5 to 8.5. More preferably, 8 is even more preferable. By maintaining the pH of the mixed solution in the vicinity of neutrality, it is possible to suppress the aggregation of the porous material and highly disperse it inside the hydrophilic film.

In order to adjust the pH of the mixed solution obtained by mixing the (meth) acrylate monomer, the surfactant, the porous material, the dispersion solvent, and the polymerization initiator within the above range, an acid may be added to the mixed solution. The acid to be added is not particularly limited, and it is preferable to use at least one of an inorganic acid and an organic acid. As the inorganic acid, at least one selected from the group consisting of hydrochloric acid, nitric acid, phosphoric acid, and sulfuric acid can be used. As the organic acid, at least one selected from the group consisting of formic acid, acetic acid, citric acid, and oxalic acid can be used.

As described above, the coating composition can be prepared by mixing a (meth) acrylate monomer, a porous substance, a surfactant, a dispersion solvent, and a polymerization initiator. And since surfactant is added, it becomes possible to suppress aggregation of a porous substance. However, even if a surfactant is added, agglomerates of porous material may be generated. If the coating composition contains aggregates of porous material, the aggregates of porous material remain in the hydrophilic film obtained from the coating composition, and the hydrophilic film is uneven. May occur.

Therefore, it is preferable to filter the mixture formed by mixing the (meth) acrylate monomer, the porous material, the surfactant, the dispersion solvent, and the polymerization initiator to remove the aggregates. By filtering using a filter, agglomerates of the porous material can be removed. Therefore, the smoothness of the resulting hydrophilic film can be improved and the appearance can be improved. The filter for filtering the mixture is not particularly limited as long as aggregates can be removed. For example, it is preferable to use a filter having a pore size of 5 μm or less. By using a filter having a pore diameter of 5 μm or less, it is possible to efficiently remove aggregates that affect the smoothness of the hydrophilic film.

Thus, the coating composition according to this embodiment includes a (meth) acrylate monomer having a functional group having a carbon-carbon unsaturated bond of 5 or more, a surfactant, and a porous substance. The coating composition further includes a (meth) acrylate monomer, a surfactant, and a dispersion solvent for dispersing the porous material. Since the hydrophilic film obtained from such a coating composition has a highly dispersed porous substance that retains moisture, the hydrophilicity of the hydrophilic film can be increased and oil can be easily removed. Further, as the (meth) acrylate monomer, a polyfunctional (meth) acrylate monomer having 5 or more functional groups having a carbon-carbon unsaturated bond is used. Therefore, since the reactivity of the (meth) acrylate monomer is high, even when a porous substance is added, it is easily cured and a strong hydrophilic film can be obtained. Furthermore, since the coating composition is easily solidified by irradiation with active energy rays, it is not necessary to use a substrate having high heat resistance. Therefore, even if it does not limit the kind of base material, it becomes possible to provide high hydrophilicity and to improve the antifouling property against oil.

The coating composition according to the present embodiment can be applied to a housing member such as a kitchen member. It can also be applied to sirocco fans and propeller fans installed in the kitchen range hood. However, the coating composition is not limited to such a house member, and can be applied to, for example, a vehicle member or a security member. Specifically, it can be applied to the surface of a vehicle-mounted lens or a security camera to impart antifouling properties.

[Hydrophilic member]
Next, the hydrophilic member according to the present embodiment will be described in detail based on the drawings. As shown in FIG. 1, the hydrophilic member 100 according to the present embodiment includes a base material 10 and a hydrophilic film 20 provided on the base material 10 and formed from a coating composition.

The substrate 10 is not particularly limited, but at least one of an inorganic substrate made of an inorganic material and an organic substrate made of an organic material can be used. Examples of the inorganic base material include ceramics such as aluminum, iron, stainless steel, galvanized steel sheet, glass, enamel, earthenware, slate, and alumina. Examples of the organic substrate include plastic materials and sheets such as polycarbonate, acrylic resin, ABS resin (acrylonitrile-butadiene-styrene resin), vinyl chloride resin, epoxy resin, and fiber reinforced plastic.

In addition, those inorganic substrates or organic substrates coated with an organic film may be used as the substrate. Examples of the organic coating include acrylic, polyester, urethane, epoxy, melamine, silicone, and fluorine coatings. In order to improve the adhesion between these films and the substrate, surface treatment such as solvent degreasing, alkali degreasing, and polishing may be performed on the substrate, and acrylic, epoxy, and silicone primers may be used. You may make it apply | coat to a base material as a base layer.

The hydrophilic film 20 is formed by curing the above-described coating composition. As shown in FIG. 1, the hydrophilic film 20 includes a base resin (acrylic resin) 21 formed by polymerizing a (meth) acrylate monomer having 5 or more functional groups having a carbon-carbon unsaturated bond, and a base resin 21. And a porous material 22 fixed by the above. The upper part of the porous substance 22 is exposed from the base resin 21, and the lower part of the porous substance 22 is supported by the base resin 21. Therefore, the porous material 22 has a configuration that is difficult to be detached from the base resin 21.

Here, in the hydrophilic film 20, the porous material 22 is located inside the base resin 21 and may not be exposed to the outside from the surface 21 a of the base resin 21. However, as described above, the porous material 22 has an action of improving hydrophilicity by adsorbing water molecules on the surface and inside. Therefore, as shown in FIG. 1, it is preferable that at least a part of the porous material 22 is exposed to the outside from the surface 21 a of the base resin 21. As a result, water molecules are easily adsorbed on the surface of the porous material 22, so that the hydrophilicity on the surface of the hydrophilic film 20 can be further improved.

As described above, it is preferable that at least one of the (meth) acrylate monomer having 5 or more functional groups and the (meth) acrylate monomer having 4 or less functional groups has a hydroxyl group in the molecule. Even when the (meth) acrylate monomer is polymerized to form the base resin 21, it is more preferable that the hydroxyl group remains in the base resin 21. When the base resin 21 has a hydroxyl group, the surface 21a of the base resin 21 has a high affinity with water. Therefore, the hydrophilicity on the surface of the hydrophilic film 20 can be further improved by a synergistic effect with the porous material 22.

In the hydrophilic member 100, the thickness of the hydrophilic film 20 is not particularly limited, but is preferably 1 μm to 100 μm, for example, and more preferably 10 μm to 80 μm. When the thickness of the hydrophilic film 20 is within this range, the porous material 22 can be highly dispersed, so that the hydrophilicity can be enhanced. Moreover, when the thickness of the hydrophilic film 20 is 100 μm or less, it is possible to firmly bond to the substrate 10 and suppress peeling.

In the hydrophilic member 100, the contact angle of water on the surface of the hydrophilic film 20 is preferably 20 ° or less, and more preferably 10 ° or less. When the contact angle of water on the surface of the hydrophilic film 20 is 20 ° or less, the hydrophilic film 20 has high hydrophilicity. For this reason, it is possible to easily remove oil adhering to the surface of the hydrophilic film. The contact angle of water can be measured by a sessile drop method.

Next, the manufacturing method of the hydrophilic member 100 of this embodiment is demonstrated. First, the surface of the base material 10 is washed to remove the dirt on the surface. The cleaning method is not particularly limited, and a known method can be used.

Next, the above-mentioned coating composition is applied to the surface of the cleaned substrate 10. At this time, the method for applying the coating composition is not particularly limited. As a method of applying the coating composition to the main surface of the substrate 10, a coating method or a printing method can be used. In the coating method, the coating composition can be applied using an air spray, a brush, a bar coater, a Mayer bar, an air knife, or the like. Also, the coating composition can be applied by spin coating. As the printing method, methods such as gravure printing, reverse gravure printing, offset printing, flexographic printing, and screen printing can be used.

In addition, after apply | coating a coating composition to the surface of the base material 10, you may dry-process as needed and may remove the dispersion | distribution solvent in a coating composition. The drying conditions are not particularly limited as long as the dispersion solvent is removed, and heat treatment may be performed as necessary.

When a photopolymerization initiator is used as the polymerization initiator, the coating composition is applied to the surface of the substrate 10 and then irradiated with active energy rays to cure the coating composition. As an active energy ray to be irradiated when the coating composition is cured, at least one of ultraviolet rays, electron beams, X-rays, infrared rays, and visible rays can be used. Of these active energy rays, ultraviolet rays or electron beams are preferably used from the viewpoint of curability and prevention of resin deterioration.

When the coating composition is cured by ultraviolet irradiation, various ultraviolet irradiation apparatuses can be used. As the ultraviolet irradiation device, a xenon lamp, a high-pressure mercury lamp, a metal halide lamp, or the like can be used. The irradiation amount of ultraviolet rays is usually 10 to 10,000 mJ / cm ² . However, from the viewpoint of enhancing the curability of the composition, the irradiation amount of ultraviolet rays is preferably 100 mJ / cm ² or more.

When a thermal polymerization initiator is used as the polymerization initiator, the coating composition is applied to the surface of the substrate 10 and then the coating composition is heated to cure the coating composition. In addition, heating conditions are not specifically limited, It can be set as the temperature which the thermal-polymerization initiator to use decompose | disassembles and generate | occur | produces active species.

As described above, the hydrophilic member 100 of the present embodiment can be produced by applying a coating composition to the substrate 10 and then curing it. Therefore, the hydrophilic member 100 having high hydrophilicity can be obtained by a simple method.

Thus, the hydrophilic member 100 according to the present embodiment includes the base material 10 and the hydrophilic film 20 provided on the base material 10 and formed from the coating composition. The hydrophilic film 20 has high hydrophilicity and can make the contact angle of water 20 ° or less. Therefore, even when oil such as oil stains adheres to the hydrophilic film 20, water can enter between the surface of the hydrophilic film 20 and the oil by bringing water into contact with the hydrophilic member 100. And since water infiltrates and an oil component floats from the hydrophilic film | membrane 20, it becomes possible to remove an oil component easily.

As the hydrophilic member 100, a housing member can be exemplified, and in particular, a kitchen member can be exemplified. Examples of the kitchen member include a range hood, a kitchen storage door, a kitchen counter, a sink, a hob, a kitchen board, a flooring around the kitchen, and a refrigerator. Thus, oil stains such as lipid peroxide are likely to adhere to the surface of the kitchen member or the like. However, by providing the hydrophilic film 20 of the present embodiment, it is possible to easily remove the initial oil stain just after adhering and the viscous oil using water. The oil stain is typically edible oil used in the kitchen, but is not limited thereto, and oils and fats caused by hand dirt, fingerprints, sebum, sweat and the like can also be removed.

Further, the hydrophilic member 100 according to the present embodiment is not limited to use for the purpose of removing oil, and can be suitably used for a portion that needs to be imparted with hydrophilicity.

Hereinafter, the present embodiment will be described in more detail with reference to examples and comparative examples, but the present embodiment is not limited to these examples.

In producing the coating compositions of Examples 1 to 12 and Comparative Examples 1 and 2, the following acrylate monomers, surfactants, porous materials and polymerization initiators were used.

・ＮＫエステルＡ－ＤＰＨ（新中村化学工業株式会社製）：ジペンタエリスリトールヘキサアクリレート（化学式２に示す６官能アクリレートモノマー）

・ＮＫエステルＡ－ＨＤ－Ｎ（新中村化学工業株式会社製）：１，６－ヘキサンジオールジアクリレート（化学式３に示す２官能アクリレートモノマー）

　＜アクリレート２＞
・ＮＫエステルＡＰＧ４００（新中村化学工業株式会社製）：ポリプロピレングリコール♯４００ジアクリレート（化学式４に示す２官能アクリレートモノマー）

・ＮＫエステル７０１Ａ（新中村化学工業株式会社製）：２－ヒドロキシ－３－アクリロイロキシプロピルメタクリレート（化学式５に示す２官能アクリレートモノマー）

・ＮＫエステルＡ－１０００（新中村化学工業株式会社製）：ポリエチレングリコール♯１０００ジアクリレート（化学式６に示す２官能アクリレートモノマー）

(Acrylate monomer)
<Acrylate 1>
NK ester A-9550W (manufactured by Shin-Nakamura Chemical Co., Ltd.): Dipentaerythritol polyacrylate (mixture of pentafunctional acrylate monomer and hexafunctional acrylate monomer shown in Chemical Formula 1)

NK ester A-DPH (manufactured by Shin-Nakamura Chemical Co., Ltd.): dipentaerythritol hexaacrylate (hexafunctional acrylate monomer represented by chemical formula 2)

NK ester A-HD-N (manufactured by Shin-Nakamura Chemical Co., Ltd.): 1,6-hexanediol diacrylate (bifunctional acrylate monomer represented by chemical formula 3)

<Acrylate 2>
NK ester APG400 (manufactured by Shin-Nakamura Chemical Co., Ltd.): Polypropylene glycol # 400 diacrylate (bifunctional acrylate monomer represented by chemical formula 4)

NK ester 701A (manufactured by Shin-Nakamura Chemical Co., Ltd.): 2-hydroxy-3-acryloyloxypropyl methacrylate (bifunctional acrylate monomer represented by chemical formula 5)

NK ester A-1000 (manufactured by Shin-Nakamura Chemical Co., Ltd.): polyethylene glycol # 1000 diacrylate (bifunctional acrylate monomer represented by chemical formula 6)

(Surfactant)
Surfactant A: DISPERBYK (registered trademark) -102 (manufactured by Big Chemie Japan), copolymer having an acidic group Surfactant B: DISPERBYK-2010 (manufactured by Big Chemie Japan), control-polymerized acrylic copolymer Polymer

(Porous material)
<Zeolite>
・ Zeolite A: X type (manufactured in-house), average pore size: 13 mm
・ Zeolite B: X type (made in-house), average pore size: 5mm
・ Zeolite C: X type (made in-house), average pore size: 3mm
・ Zeolite D: Y type (made in-house), average pore size: 13 mm
<Clay-based porous adsorbent>
・ Kunipia (registered trademark) -F (manufactured by Kunimine Kogyo Co., Ltd.), the main component is layered silicate mineral <Carbon-based porous adsorbent>
Graphene nanoplatelet dispersion M-5 (Wako Pure Chemical Industries, Ltd.)

(Polymerization initiator)
Polymerization initiator A: Irgacure (registered trademark) 184 (Merck), 1-hydroxycyclohexyl phenyl ketone Polymerization initiator B; Irgacure 754 (Merck), oxyphenylacetic acid, 2- [2-oxo-2- Phenylacetoxyethoxy] ethyl ester and oxyphenylacetic acid, 2- (2-hydroxyethoxy) ethyl ester mixture
Polymerization initiator C: water-soluble azo polymerization initiator V-501 (manufactured by Wako Pure Chemical Industries, Ltd.), 4,4′-azobis (4-cyanovaleric acid)

[Preparation of coating composition]
The coating compositions of Examples 1 to 12 and Comparative Examples 1 and 2 were prepared as follows. Specifically, the acrylate monomer, surfactant, porous material and polymerization initiator shown in Table 1 were mixed in the amounts shown in Table 1. At this time, as a stirrer, a rotating / revolving mixer Awatori Nertaro (registered trademark) (manufactured by Sinky Co., Ltd.) was used, and these raw materials were sufficiently mixed by stirring at a predetermined rotational speed. And the coating composition of each example was obtained by filtering the obtained mixture with the filter with a hole diameter of 5 micrometers, and removing an aggregate.

In Example 1, a polyfunctional acrylate monomer is used and 10% by mass of zeolite A is added to the resin component. Example 2 is an example prepared in the same manner as in Example 1 except that a polyfunctional acrylate monomer different from that in Example 1 was used. Example 3 is an example prepared in the same manner as in Example 1 except that 3% by mass of zeolite A was added to the resin component.

Example 4 is an example prepared in the same manner as Example 1 except that zeolite B having an average pore diameter smaller than that of zeolite A was used. Example 5 is an example prepared in the same manner as Example 1 except that zeolite C having an average pore diameter smaller than that of zeolite A was used.

Example 6 is an example using an acrylate monomer having a small number of functional groups in addition to the polyfunctional acrylate monomer. Example 7 is an example prepared in the same manner as Example 6 except that the amount of the acrylate monomer having a small number of functional groups was increased. Example 8 is an example prepared in the same manner as in Example 6 except that the addition amount of the acrylate monomer having a small number of functional groups was further increased.

Example 9 is an example prepared in the same manner as in Example 1 except that a clay-based porous adsorbent was used instead of zeolite A. Example 10 is an example prepared in the same manner as in Example 1 except that a carbon-based porous adsorbent was used instead of zeolite A.

Example 11 is an example in which, in addition to the polyfunctional acrylate monomer, an acrylate monomer having a small number of functional groups and having a hydroxyl group is used, and further Y-type zeolite is used. Example 12 is an example using an acrylate monomer having a small number of functional groups in addition to the polyfunctional acrylate monomer.

Comparative Example 1 is an example prepared in the same manner as in Example 1 except that the surfactant and the porous material are not used. Comparative Example 2 is an example prepared in the same manner as in Example 1 except that only an acrylate monomer having a small number of functional groups was used as the acrylate monomer.

[Preparation of test sample]
First, an acrylic plate as a substrate was prepared and the surface was washed. Next, the coating composition of each example was applied to the surface of the acrylic plate by spin coating, and then dried at 80 ° C. for 60 minutes to remove the solvent. Thereafter, the applied coating composition was cured by irradiating with ultraviolet rays. Thereby, the test sample of each example which formed the film in the surface of an acrylic board was prepared. The ultraviolet irradiation was performed using a Spot UV irradiation device Spot Cure (registered trademark) SP-9 manufactured by USHIO INC. Moreover, the thickness of the film in the test sample of each example was about 50 μm.

However, the coating composition of Comparative Example 2 could not be cured even when irradiated with ultraviolet rays. This is because the (meth) acrylate monomer having 5 or more functional groups was not used, and the reactivity of the (meth) acrylate monomer was reduced by the addition of zeolite, and the coating was not sufficiently cured. Conceivable.

[Evaluation]
(Contact angle measurement)
The contact angles of the coatings provided on the surfaces of the test samples of Examples 1 to 12 and Comparative Example 1 were measured. The contact angle was determined by a sessile drop method, and pure water was used as a droplet. As a contact angle meter, a fully automatic contact angle meter DM-300 manufactured by Kyowa Interface Science Co., Ltd. was used. Table 1 shows the water contact angle of each test sample. In addition, since the film of the test sample of Comparative Example 2 was not cured, the contact angle could not be measured.

As shown in Table 1, it can be seen that in the test samples of Examples 1 to 12, the water contact angle of the coating is 20 ° or less, and the hydrophilicity is excellent. In contrast, the test sample of Comparative Example 1 has a water contact angle of the coating exceeding 50 °, indicating that it is poor in hydrophilicity. That is, since the test samples of Examples 1 to 12 include a porous material capable of holding water, the porous material exposed on the coating surface adsorbs moisture, and the affinity of water on the coating surface Is increasing. As a result, the water contact angle of the coating is 20 ° or less, and it is considered that the hydrophilicity is improved.

When the test samples of Example 3, Example 9 and Example 10 are compared, it can be seen that all the test samples have a water contact angle of the coating of 20 ° or less. Therefore, it can be seen that clay particles and carbon particles can be used as the porous material in addition to zeolite.

When the test samples of Example 3, Example 4 and Example 5 are compared, it can be seen that the water contact angle of the coating is 15 ° or less for any of the test samples. Furthermore, it turns out that the water contact angle of a film becomes small as the average pore diameter of a zeolite becomes small. Therefore, it can be seen that the average pore diameter of zeolite is preferably 13 mm or less, more preferably 5 mm or less.

Moreover, when the test samples of Example 1 and Example 3 are compared, since Example 3 has a lower zeolite content than Example 1, the hydrophilicity of the resulting coating is lowered and the water contact angle is increased. Yes. However, Example 11 having the same amount of zeolite as Example 3 uses an acrylate monomer having a hydroxyl group, so that the hydrophilicity of the resulting coating is improved and the water contact angle is equivalent to Example 1. I understand.

Even when an acrylate monomer having 2 functional groups is used in addition to an acrylate monomer having 5 or more functional groups as in Examples 6 to 8, the hydrophilicity of the coating is improved and the water contact angle is 20 ° or less. I understand that

(Dirt removal test)
The dirt removal test was performed on the coatings provided on the surfaces of the test samples of Examples 1 to 12 and Comparative Example 1. Specifically, first, salad oil was sprayed and applied to the coating provided on the test sample of each example.

Next, the test sample to which the salad oil adhered was immersed in water, and the floating condition of the salad oil was visually observed. The case where the salad oil separated from the surface of the test sample and floated in water was evaluated as “◯”. On the other hand, the case where the salad oil did not separate from the surface of the test sample and remained attached was evaluated as “x”. In addition, since the film of the test sample of Comparative Example 2 was not cured, the stain removal test could not be performed.

As shown in Table 1, it can be seen that the test samples of Examples 1 to 12 have high coating hydrophilicity, so that salad oil can be separated and oil stains can be easily removed simply by dipping in water. On the other hand, since the test sample of Comparative Example 1 has low hydrophilicity of the coating, it can be seen that the salad oil is in close contact and cannot be removed simply by immersing in water.

As mentioned above, although this embodiment was demonstrated by the Example and the comparative example, this embodiment is not limited to these, A various deformation | transformation is possible within the range of the summary of this embodiment.

The entire contents of Japanese Patent Application No. 2017-118633 (filing date: June 16, 2017) are incorporated herein by reference.

According to the present invention, it is provided with a coating composition capable of imparting high hydrophilicity without limiting the type of substrate and enhancing antifouling properties against oil, and a hydrophilic film obtained from the coating composition. A hydrophilic member can be obtained.

DESCRIPTION OF SYMBOLS 10 Base material 20 Hydrophilic film | membrane 22 Porous substance 100 Hydrophilic member

Claims (6)

A (meth) acrylate monomer having 5 or more functional groups having a carbon-carbon unsaturated bond;
A surfactant,
A porous material;
A dispersion solvent for dispersing the (meth) acrylate monomer, the surfactant, and the porous material;
A coating composition comprising: The coating composition according to claim 1, wherein the content of the porous substance with respect to the (meth) acrylate monomer is 1 to 30% by mass. The coating composition according to claim 1 or 2, wherein the porous substance is zeolite. The coating composition according to claim 1 or 2, wherein the porous substance is carbon particles. The coating composition according to any one of claims 1 to 4, wherein the surfactant is a copolymer having an acidic group in a molecule. A substrate;
A hydrophilic film provided on the substrate and formed from the coating composition according to any one of claims 1 to 5,
A hydrophilic member comprising:

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