KR20140126653A - Surface modifiers - Google Patents

Abstract

The present invention relates to a surface modifier which gives hydrophilia and anti-fouling properties to the surface of a film formed by a coating agent by being mixed with the coating agent forming the film in small quantity. To this end, provided is a surface modifier which gives hydrophilia to the surface of a film smoothly formed by preventing crater phenomenon and anti-fouling properties as a result by being mixed with a coating agent forming the film such as paint in small quantity. Also, provided are the coating agent and a film formed by spreading and curing the same.

Description

Surface Modifiers {SURFACE MODIFIERS}

The present invention relates to a surface conditioner that imparts hydrophilicity and antifouling property to the surface of a coating formed of the coating agent by blending a small amount of the coating agent to form the coating.

In recent years, there has been a desire to improve the antifouling property of the coating film formed by various coating agents such as aqueous and oily coatings, baking coatings, and inks, with high added value using such a silica film.

Generally, as a method of imparting hydrophilicity to a coating film, the surface of the formed film is often made hydrophilic by making the resin itself contained in the coating agent for forming the coating film or the crosslinkable component itself forming the film hydrophilic (for example, See Patent Documents 1 to 5). However, in this case, the resin or hydrophilic resin is selected or the resin or the crosslinkable component is functionalized, so that the entire resin becomes hydrophilic, so that resins and crosslinkable components that can be used depend on the application of the coating. In addition, as a result of imparting hydrophilicity to the coating agent, the entire film becomes hydrophilic, so that the penetration of water into the inside of the film tends to occur, and there is a concern about the durability of the film itself. When the conventional coating agent is modified to impart hydrophilicity thereto, it is necessary to improve the resin or the crosslinkable component for forming the coating film, and a considerable review of the resin or the like is required for each coating agent.

As another method for imparting hydrophilicity to the coating film, there is a case where the coating film formed by the existing coating agent is coated with the above-mentioned hydrophilic coating agent to form a film to impart hydrophilicity. However, in this case, since the film is a hydrophilic film in a state (laminated state) separated from the coating film formed by the existing coating agent, weather resistance is hardly obtained due to film separation due to delamination. In addition, since the coating film is gradually peeled off, the surface shape of the coating film changes, and appearance defects such as gloss decrease appear. In addition, in recent years, there have been many requests for hydrophilizing baking paints, and examples of applications thereof include outdoor-use warehouses and pre-coated metal for roofs. These coatings require long-term weatherability.

On the other hand, as a method for imparting hydrophilicity to the coating film without changing the resin or the crosslinkable component, a hydrophilic surface modifier may be added to the existing coating agent. In this case, by adding a small amount of the hydrophilic surface modifier, the surface of the coating film can be hydrophilized without changing physical properties required for the coating, such as durability and hardness of the formed coating. As the hydrophilic surface modifier, silicates typified by ethyl silicate, which is mostly hydrophilicized by hydrolysis, are often used. Since the silicates require a time of about 2 to 3 months for the hydrolysis at the coating surface, the coating becomes a hydrophobic surface immediately after formation of the coating due to the non-water-soluble silicate flow, Lt; / RTI > Although long-term hydrophilic properties can be exhibited after hydrophilic expression by the hydrolysis of silicates, long-term hydrophilicity may cause water to penetrate into the inside of the film gradually, which may lower the durability of the film itself. Further, as a problem of a coating agent containing a hydrophilic surface modifier such as a silicate, it is also said that the hydrophilic surface modifier itself is liable to cause defects in view of stability with time, such as gelation of the hydrophilic surface modifier itself and increase in viscosity of the coating agent due to crosslinking with the resin . The hydrophilic surface modifier itself is hydrolyzed by moisture in the air to become highly polarized, and the surface orientation property due to the hydrophobicity of the silicate species is lost, and the hydrophilization performance is lowered.

There is a hydrophilic surface modifier containing a polyalkylene oxide which is a hydrophilic segment, which exhibits hydrophilicity from the beginning of film formation. The coating material containing such a hydrophilic surface modifier is relatively suitable for forming a coating film at room temperature. However, when a film is formed by baking at a high temperature such as a baking coating material, a coating material having hydrophilic properties such as thermal decomposition or hydrolysis The tendency of degradation of expression performance is recognized. In addition, since the hydrophilic surface modifier easily stabilizes the bubbles in the coating agent, fine bubbles formed during coating of the coating agent may generate bubble traces (crushing phenomenon) during baking.

Further, Patent Document 6 discloses a hydrophilic surface modifier having a silicone macromonomer such as siloxane-containing acrylates, and a hydrophilic organofunctional silicone polymer in which an unsaturated polyether component and acrylamides are radically polymerized . This hydrophilic surface modifier needs to contain 30% or more of the polyether component in the polymer. The coating material containing the hydrophilic surface modifier tends to generate pyrolysis of the polyether component in the high-temperature baking process, and the scattered decomposition product may contaminate facilities such as the baking furnace. In addition, the coating formed from the coating agent has a hydrophobic silicone portion and a hydrophilic polyether portion, which results in a high-polarity amphipathic skeleton, which makes it easy to stabilize bubbles in the coating agent and easily cause a crater phenomenon.

Even when these surface conditioners and antifoaming agents are added to the coating agent, there is a case where the coating formed by the coating agent has a problem of a crater phenomenon. The occurrence of the crater phenomenon not only greatly damages the appearance of the coating but also deteriorates the film breakage from the defect and the protective effect of the substrate. As described above, according to the coating agent containing the conventional hydrophilic surface modifier, it is very difficult to completely prevent the crater phenomenon even if hydrophilic properties can be expressed in the formed film from the beginning.

JPH5-179145A JPH7-196977A JPH9-31401A JP 2002-80789 A JPH4-370176A JP 2008-542462 A

Disclosure of the Invention The present invention has been made in order to solve the above problems, and it is an object of the present invention to provide a coating agent such as a paint for forming a coating, A coating agent, and a coating formed by applying and curing the coating agent.

In order to achieve the above object, the surface modifier according to claim 1 of claim 1 is characterized by containing at least one acrylamide monomer selected from the group consisting of dimethyl (meth) acrylamides and diethyl (meth) acrylamides at 80.00 to 99.99 weight 0.01 to 20.00 parts by weight of a siloxy group-containing mono (meth) acrylate monomer represented by the following formula (1) and a siloxy group-containing mono (meth) acrylate- At least one functional group-containing monomer selected from (meth) acrylate-containing and (meth) acrylate-containing (meth) acrylate groups is contained in an amount of at most 10 parts by weight and at least the acrylamide monomer and the siloxy group- Is copolymerized and has a weight average molecular weight of 1500 to 50000 Characterized in that for imparting hydrophilicity to the film surface:

[Formula 1]

R ² represents a hydrogen atom or a methyl group; R ² represents an alkylene group of 1 to 10 carbon atoms; R ³ represents an alkyl group of 1 to 12 carbon atoms; and m represents a number of 2 to 150.

The coating agent according to claim 2 is characterized by containing the surface conditioner according to claim 1 and a film-forming component.

The coating film according to claim 3 is the coating material according to claim 2, characterized in that it is coated on a substrate and formed by curing.

The coating film according to claim 4 is the coating film according to claim 3, characterized in that it has antifouling property on the surface of the coating film due to the hydrophilicity.

According to the surface conditioner of the present invention, hydrophilic property can be imparted to the surface of the film immediately after the film formation without requiring a reaction such as hydrolysis, even if only a small amount is added to the coating agent. It is possible to improve cleaning property by water and to exhibit antifouling property.

In addition, the coating agent of the present invention containing this surface conditioner has no change in the performance of the surface conditioner at the time of storage and / or viscosity change of the coating agent due to the surface conditioner, and is excellent in storage stability. In addition, defoaming and fouling by the antifoaming agent incorporated in the coating is promoted, and prevention of the cratering phenomenon is achieved, so that a smooth film can be formed.

The coating formed of the coating agent is hydrophilic and imparts hydrophilicity to the surface, and is excellent in smoothness and laminating characteristics, and has excellent heat resistance without generation of puddle or foreign matter during printing.

Hereinafter, embodiments for carrying out the present invention will be described in detail, but the scope of the present invention is not limited to these embodiments.

The surface modifier of the present invention can be prepared by reacting dimethyl (meth) acrylamides such as N, N-dimethylacrylamide or N, N-dimethylmethacrylamide and N, N-diethylacrylamide or N, N- (Meth) acrylamides such as ethyl acrylate and ethyl methacrylate, and 0.01 to 20.00 parts by weight of a siloxy group-containing mono (meth) acrylate monomer, . The surface control agent is used to be added to various coating agents as a film-forming composition in order to form a coating by curing. When the acrylamide monomer is less than 80 parts by weight, the obtained surface control agent can not exhibit sufficient hydrophilicity to the coating film. In addition, the compatibility with other components to be blended in the coating agent containing the surface modifier is extremely deteriorated. In addition, not only is it possible to form a depression at the time of coating or to form a concave portion on the surface of the coating film, The leveling property of the surface layer is deteriorated, and sufficient overcoat adhesion can not be obtained. It is preferable that 90 to 99 parts by weight of the acrylamide monomer and 1 to 10 parts by weight of the siloxy group-containing mono (meth) acrylate monomer are contained.

(Meth) acrylates, hydroxyl group-containing (meth) acrylamides, and block isocyanate group-containing (meth) acrylates in the copolymer of the acrylamide monomer and the siloxy group-containing mono (meth) Acrylate may be copolymerized with at least one of the functional group-containing monomers selected from the group consisting of acrylates and acrylates. The functional group-containing monomer is preferably 10 parts by weight or less based on the total weight of the (meth) acrylamide monomer and the siloxy group-containing mono (meth) acrylate monomer. As a result, since the surface of the coating film reacts with the resin in the coating material, elution of the surface control agent due to rainwater is less likely to occur, and it can act advantageously on antifouling properties. If the amount is more than 10 parts by weight, the inherent performance may be impaired. These functional group-containing monomers may be used alone or in combination if the total amount is not more than the specified amount.

The weight average molecular weight of the copolymer is in the range of 1500 to 50,000. When the weight-average molecular weight is less than 1,500, bubble problems tend to occur at the time of coating the copolymer-containing coating agent. On the other hand, when the weight average molecular weight exceeds 50000, the orientation property to the coating surface is lowered and sufficient hydrophilicity can not be obtained. It is preferable that the weight average molecular weight of the copolymer is 2500 to 20,000.

As the siloxy group-containing mono (meth) acrylate monomer, a siloxy group-containing mono (meth) acrylate monomer represented by the following general formula (1)

[Formula 1]

R ¹ represents a hydrogen atom or a methyl group; R ² represents an alkylene group having 1 to 10 carbon atoms; R ³ represents an alkyl group having 1 to 12 carbon atoms; and m represents an integer of 2 to 150.

The siloxy group-containing mono (meth) acrylate monomer represented by the general formula (1) is preferably selected from the group consisting of Siranapren FM-0711, Siranapren FM-0721, Siranapren FM- X-22-174DX, X-22-2426, X-22-2475 (all of which are registered trademarks of Shin-Etsu Chemical Co., Ltd.); )).

Examples of the acrylamide monomer include dimethyl (meth) acrylamides and diethyl (meth) acrylamides such as N, N-dimethyl acrylamide DMAA, N, N-diethylacrylamide DEAA And the product name of KOHJIN Holdings Co., Ltd.).

Examples of the hydroxyl group-containing (meth) acrylates include 2-hydroxyethyl (meth) acrylate. (Meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (For example, Fraxel FM series) in which? -Caprolactone is added to (meth) acrylate. Examples of the hydroxyl group-containing (meth) acrylamides include N-hydroxyethyl acrylamide and N-hydroxymethylacrylamide. The (meth) acrylate containing a block isocyanate group is a (meth) acrylate monomer having an isocyanate group blocked with a block block, for example, a block copolymer of 2-isocyanatoethyl (meth) There may be mentioned those obtained by reacting ethyl alcohol, isopropyl alcohol, caprolactam, MEK-oxime, dimethyl pyrazole, diethyl malonate or the like.

(Meth) acrylate, at least one unsaturated monomer selected from alkyl (meth) acrylates, (meth) acrylamides and vinyl group-containing compounds in the copolymer of the acrylamide monomer and the siloxy group- May be copolymerized. However, the copolymerization amount of the unsaturated monomer should be such that the obtained copolymer does not impair the hydrophilicity-imparting performance, and it is preferably 30% by weight or less based on the total weight of the acrylamide monomer and the siloxy group-containing mono (meth) acrylate monomer .

The alkyl (meth) acrylates are, for example, alkyl acrylates or alkyl methacrylates, such as methyl (meth) acrylate, ethyl (meth) acrylate, n- (Meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, tert-butyl (Meth) acrylate, isodecyl (meth) acrylate, dodecyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl -Acryloyloxyethyl-succinic acid, 2-acryloyloxyethyl-phthalic acid, tetrahydrofurfuryl (meth) acrylate, and the like.

(Meth) acrylamides other than dimethyl (meth) acrylamides and diethyl (meth) acrylamides include, for example, dimethylaminopropyl (meth) acrylamide, isopropyl (Meth) acryloyl morpholine, di (meth) acrylamide, (meth) acrylamide-tert-butylsulfonic acid, (meth) acrylamide- And the like.

The vinyl group-containing compounds include, for example, a linear chain having 1 to 12 carbon atoms such as n-butyl vinyl ether, isobutyl vinyl ether, tert-butyl vinyl ether, cyclohexyl vinyl ether and lauryl vinyl ether , Branched or cyclic alkyl vinyl ether monomers; Vinyl ester monomers such as vinyl acetate, vinyl propionate and vinyl laurate.

This copolymer can be obtained by a radical polymerization method. Examples of the radical polymerization method include a method in which a predetermined amount of at least one acrylamide monomer selected from dimethyl (meth) acrylamide and diethyl (meth) acrylamide, a predetermined siloxy group-containing mono (meth) acrylate monomer, Containing monomer having at least one functional group selected from hydroxyl group-containing (meth) acrylates, hydroxyl group-containing (meth) acrylamides and block isocyanate group-containing (meth) acrylates, At least one unsaturated monomer selected from a predetermined amount of alkyl (meth) acrylates, (meth) acrylamides and vinyl group-containing compounds, if necessary, is appropriately added in a solvent in the presence of a radical polymerization initiator, Therefore, it can be obtained by random copolymerization in the presence of a chain transfer agent. As the radical polymerization initiator, for example, tert-butylperoxy-2-ethylhexanoate may be used, and as the chain transfer agent, for example, dodecylmercaptan may be used. As the solvent, for example, an inert solvent such as cyclohexanone may be used. The copolymer may be obtained by radical polymerization or ion polymerization such as anion polymerization. The copolymer may be a random copolymer, a block copolymer, a graft copolymer, or an alternating copolymer.

The surface-modifying agent containing the obtained copolymer may be composed solely of the copolymer or may be used by dissolving or suspending the copolymer in an inert solvent. An inert solvent is one capable of dissolving or suspending the copolymer. Specifically, hydrocarbon solvents such as xylene, toluene and cyclohexane; Ketone solvents such as cyclohexanone and methyl isobutyl ketone; Ether solvents such as methyl cellosolve, cellosolve, butyl cellosolve, methyl carbitol, carbitol, butyl carbitol, diethyl carbitol, propylene glycol monomethylether; Ester solvents such as n-butyl acetate, isobutyl acetate, n-amyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate, 3-methoxybutyl acetate; alcohol solvents such as n-butyl alcohol, sec-butyl alcohol, isobutyl alcohol, cyclohexanol, 2-ethylhexanol and 3-methyl-3-methoxybutanol. These solvents may be used alone or in combination of plural kinds thereof

The coating agent contains a surface conditioner and a film-forming component. When this surface conditioner is formulated to prepare a coating agent, a known coating agent containing no surface conditioner and containing a film-forming component is prepared in advance, and then the surface conditioner is mixed and kneaded to obtain a desired coating agent. They may be mixed at the same time or in any order. It is preferable that the coating agent is formulated so as to be a copolymer of 0.1 to 10% by weight, preferably 0.5 to 5.0% by weight in terms of solid content based on the whole amount of the coating agent. The coating composition may be blended with a film forming component or a third component other than an inert solvent. The third component is not particularly limited, and examples thereof include colorants such as pigments and dyes, resins, diluting solvents, catalysts, and surfactants. If necessary, a sensitizer, an antistatic agent, a defoaming agent, a dispersant, and a viscosity adjusting agent may be added.

Examples of the resin as the film-forming component to be blended in the coating agent include acrylic resin, polyester resin, urethane resin, alkyd resin, epoxy resin and polyamine resin. The resin is cured by chemical reaction in the presence or absence of a catalyst, such as, for example, a heat curing type, an ultraviolet curing type, an electron beam curing type, an oxidative curing type, a light cation curable type, a peroxide curing type, and an acid / epoxy curing type Or may be a resin having a high glass transition point, which does not involve a chemical reaction, and may become a film only by volatilizing the solvent.

The diluting solvent is not particularly limited as long as it is generally usable water or an organic solvent. Examples of the organic solvent include hydrocarbon solvents such as xylene, toluene and cyclohexane; Ketone solvents such as cyclohexanone and methyl isobutyl ketone; Ether solvents such as methyl cellosolve, cellosolve, butyl cellosolve, methyl carbitol, carbitol, butyl carbitol, diethyl carbitol, propylene glycol monomethylether; Ester solvents such as n-butyl acetate, isobutyl acetate, n-amyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate, 3-methoxybutyl acetate; alcohol solvents such as n-butyl alcohol, sec-butyl alcohol, isobutyl alcohol, cyclohexanol, 2-ethylhexanol and 3-methyl-3-methoxybutanol. These solvents may be used alone or in combination.

The coating material containing the surface modifier is applied to the surface of the base material, and the resulting coating film is dried or cured to form a film having a hydrophilic surface. This film is easily hydrophilic to water due to the hydrophilicity of its surface, and thus has an antifouling property that it is easy to be cleaned with water such as rainwater even if dust adheres.

The base material is not particularly limited, but is formed of a material such as plastic, rubber, paper, wood, glass, metal, stone, cement, mortar and ceramics, and includes household electrical appliances, automobile exterior materials, daily necessities and building materials .

Examples of the application method of the coating agent include a spin coat, a slit coat, a spray coat, a dip coat, a bar coat, a doctor blade, a roll coat and a flow coat.

As described above, the coating formed by applying the coating agent containing the surface modifier of the present invention to the surface of the substrate and curing the coating is smooth and smooth, and hydrophilicity is imparted to the surface immediately after the coating is formed. As a result, The cleaning property by water is improved and antifouling property can be exhibited. That is, the surface conditioner does not require a reaction such as hydrolysis for imparting hydrophilicity, and can provide a hydrophilic surface immediately after the film is formed. According to the coating film formed of the coating agent containing the surface modifier as described above, even when a film forming component such as a hydrophobic resin having a low surface tension is used, the formed film surface can be hydrophilized and the wettability when the coating agent having a high surface tension is applied It is possible to improve the extensibility and improve the smoothness of the over coating film from the effect. In addition, by hydrophilizing the surface of the coating film, the hydrophilic surface has a low water contact angle with respect to the substrate, and can be cleaned by water such as rainwater, thereby exhibiting high antifouling properties. This antifouling property is also expressed immediately after the film formation.

Since the surface modifier has a high polarity amphipathic skeleton as in the hydrophilic organofunctional silicone copolymer described in Patent Document 6 described above at room temperature, it has excellent compatibility with the film-forming component, but is in a state in which it is difficult to stabilize the bubbles. The detailed reason is not necessarily clear, but it is assumed as follows. This surface modifier contains a copolymer containing acrylamide as a main component. The copolymer has a hydrophobic polysiloxane segment and a segment derived from hydrophilic / hydrophobic acrylamide. Since acrylamide has a hydrophobic part and a hydrophilic part in its structure, a copolymer having segments derived from dimethyl and / or diethyl (meth) acrylamide becomes a thermosensitive polymer in an aqueous solution. This is also observed when a monomer is copolymerized to a certain extent. Polymers containing acrylamide as a main component are converted to hydrophilic / hydrophobic before and after the temperature difference. According to this characteristic, during the baking step in which the crater phenomenon occurs, the surface conditioner is changed from hydrophilic to hydrophobic, the stabilized bubbles become unstable due to the phase change of the surface conditioner, and the defoaming and spreading by the defoaming agent is promoted , Crater phenomenon prevention is achieved. After firing, when the temperature is returned to room temperature, the hydrophobic property becomes hydrophilic again, and the formed film has hydrophilic property.

When a coating containing the surface control agent is applied to a substrate to form a coating film, the surface control agent also has high orientation to the interface, and leveling property is also exhibited by the effect of uniformizing the surface tension, Surface defects are minor. In addition, even when the coating is applied thereto, uneven paint does not occur, adhesion between the coating and the overcoat layer is not deteriorated, and the coating and the overcoat layer are not peeled off. Further, as in the case of coating a precoat metal coating agent, since the heat resistance is excellent even when baking treatment is performed at a high temperature, it is possible to provide a coating film having excellent smoothness, And the durability is excellent.

(Example)

Examples in which the surface conditioner of the present invention is prepared are shown in Examples 1 to 9, and examples in which surface conditioners other than the present invention are prepared are shown in Comparative Examples 1 to 7.

≪ Example 1 >

100 parts by weight of cyclohexanone was added to a 1000 ml reaction vessel equipped with a stirrer, a reflux condenser, a dropping funnel, a thermometer and a nitrogen gas inlet, and the temperature was raised to 110 DEG C in a nitrogen gas atmosphere. The temperature of the cyclohexanone was maintained at 110 占 폚, and the dropwise addition solution (a-1) shown in the following Table 1 was dropped at a constant rate for 2 hours by a dropping funnel to prepare a monomer solution. After completion of the dropwise addition, the monomer solution was heated to 115 DEG C and reacted for 2 hours to synthesize a copolymer to obtain a surface conditioner. (Column: TSKGEL SUPERMULTIPORE HZ-M as a product of TOSOH CORPORATION, THF (tetrahydrofuran) as an eluting solvent), and the obtained surface-modifying agent was dissolved in a solvent of molecular weight A calibration curve was obtained from a polystyrene standard material having a known molecular weight in advance and the weight average molecular weight of the surface conditioner was determined by comparing the molecular weight distribution of the surface conditioner with that of the surface conditioner. The weight average molecular weight was 3500 in terms of polystyrene.

≪ Example 2 >

A copolymer was synthesized in the same manner as in Example 1 except that the loading solution in Example 1 was changed to (a-2) in Table 1 and the dropping temperature was changed to 90 ° C to obtain a surface conditioner. The weight average molecular weight of the obtained surface control agent was determined by gel permeation chromatography in the same manner as in Example 1, and found to be 8000 in terms of polystyrene.

≪ Example 3 >

A copolymer was synthesized in the same manner as in Example 1 except that the loading solution in Example 1 was changed to (a-3) in Table 1 and the dropping temperature was changed to 90 ° C to obtain a surface conditioner. The weight average molecular weight of the obtained surface control agent was determined by gel permeation chromatography in the same manner as in Example 1, and found to be 15,000 in terms of polystyrene.

<Example 4>

A copolymer was synthesized in the same manner as in Example 1 except that the loading solution in Example 1 was changed to (a-4) in Table 1 to obtain a surface conditioner. The weight average molecular weight of the obtained surface control agent was determined by gel permeation chromatography in the same manner as in Example 1, and found to be 3500 in terms of polystyrene.

&Lt; Example 5 >

A copolymer was synthesized in the same manner as in Example 1 except that the loading solution in Example 1 was changed to (a-5) in Table 1 and the dropping temperature was changed to 90 ° C to obtain a surface conditioner. The weight average molecular weight of the obtained surface control agent was determined by gel permeation chromatography in the same manner as in Example 1, and found to be 8,000 in terms of polystyrene.

&Lt; Example 6 >

A copolymer was synthesized in the same manner as in Example 1 except that the loading solution in Example 1 was changed to (a-6) in Table 1 to obtain a surface conditioner. The weight average molecular weight of the obtained surface control agent was determined by gel permeation chromatography in the same manner as in Example 1, and found to be 4500 in terms of polystyrene.

&Lt; Example 7 >

A copolymer was synthesized in the same manner as in Example 1 except that the loading solution in Example 1 was changed to (a-7) in Table 1 and the dropping temperature was changed to 90 ° C to obtain a surface conditioner. The weight average molecular weight of the obtained surface control agent was determined by gel permeation chromatography in the same manner as in Example 1, and found to be 8,000 in terms of polystyrene.

&Lt; Example 8 >

A copolymer was synthesized in the same manner as in Example 1 except that the dropping solution in Example 1 was changed to (a-8) in Table 1 and the dropping temperature was changed to 90 ° C to obtain a surface conditioner. The weight average molecular weight of the obtained surface control agent was determined by gel permeation chromatography in the same manner as in Example 1, and found to be 2000 in terms of polystyrene.

&Lt; Example 9 >

A copolymer was synthesized in the same manner as in Example 1 except that the loading solution in Example 1 was changed to (a-9) in Table 1 and the dropping temperature was changed to 90 ° C to obtain a surface conditioner. The weight average molecular weight of the obtained surface control agent was determined by gel permeation chromatography in the same manner as in Example 1, and found to be 3500 in terms of polystyrene.

[Table 1]

&Lt; Comparative Example 1 &

100 parts by weight of cyclohexanone was added to a 1000 ml reaction vessel equipped with a stirrer, a reflux condenser, a dropping funnel, a thermometer and a nitrogen gas inlet, and the temperature was raised to 110 DEG C in a nitrogen gas atmosphere. The temperature of the cyclohexanone was maintained at 110 占 폚 and the dropwise addition solution (b-1) shown in the following Table 2 was dropwise added at a constant rate for 2 hours by a dropping funnel to prepare a monomer solution. After completion of the dropwise addition, the monomer solution was heated to 115 DEG C and reacted for 2 hours to synthesize a copolymer to obtain a surface conditioner. Molecular weight distribution was determined by eluting the obtained surface-modifying agent every molecular weight by gel permeation chromatography (column: TSKGEL SUPERMULTIPORE HZ-M, product of Tosoh Corporation, which can separate molecules having different molecular weights, THF as an eluting solvent). A calibration curve was obtained from a polystyrene standard material having a known molecular weight in advance and the weight average molecular weight of the surface control agent was determined by comparing with the molecular weight distribution of the surface control agent. As a result, the weight average molecular weight of this surface conditioner was 3500 in terms of polystyrene. In Comparative Example 1, no acrylamide monomer was added to the monomer solution.

&Lt; Comparative Example 2 &

The dripping solution in Comparative Example 1 was changed to (b-2) in Table 2, and a copolymer was synthesized in the same manner as in Comparative Example 1 to obtain a surface conditioner. The weight average molecular weight of the obtained surface control agent was determined by gel permeation chromatography in the same manner as in Comparative Example 1, and found to be 10,000 in terms of polystyrene. In Comparative Example 2, the acrylamide monomer in the monomer solution was less than 80 parts by weight, and the siloxy group-containing mono (meth) acrylate monomer was more than 20 parts by weight.

&Lt; Comparative Example 3 &

A copolymer was synthesized in the same manner as in Comparative Example 1 except that the dropping solution in Comparative Example 1 was changed to the following (b-3) in Table 2 and the dropping temperature was changed to 90 ° C to obtain a surface conditioner. The weight average molecular weight of the obtained surface control agent was determined by gel permeation chromatography in the same manner as in Comparative Example 1, and found to be 70000 in terms of polystyrene. In Comparative Example 3, the weight average molecular weight of the obtained surface control agent exceeded 50,000.

&Lt; Comparative Example 4 &

The dripping solution in Comparative Example 1 was changed to (b-4) in Table 2, and a copolymer was synthesized in the same manner as in Comparative Example 1 to obtain a surface conditioner. The weight average molecular weight of the obtained surface control agent was determined by gel permeation chromatography in the same manner as in Comparative Example 1, and found to be 4000 in terms of polystyrene. In Comparative Example 4, no acrylamide monomer was added to the monomer solution.

&Lt; Comparative Example 5 &

The dripping solution in Comparative Example 1 was changed to (b-5) in Table 2, and a copolymer was synthesized in the same manner as in Comparative Example 1 to obtain a surface conditioner. The weight average molecular weight of the obtained surface control agent was determined by gel permeation chromatography in the same manner as in Comparative Example 1, and found to be 4000 in terms of polystyrene. In Comparative Example 4, the siloxy group-containing mono (meth) acrylate monomer was not added to the monomer solution.

&Lt; Comparative Example 6 >

Ethyl silicate 48 (manufactured by COLCOAT CO., Ltd.) was used as a surface conditioner.

[Table 2]

&Lt; Example 10, Comparative Example 8 >

The surface conditioner obtained in Examples 1 to 9 and Comparative Examples 1 to 6 was blended in a preliminarily prepared preparation paint to obtain a test paint as a coating agent. The properties of the cured coating obtained by applying the test coating to the substrate and the stability with time of the test coating were evaluated.

(Preparation of preparation paint)

324 parts by weight of BETCO LIGHT M-6154-40 (polyester polyol resin, nonvolatile content: 50%, hydroxyl value: 50, manufactured by Dainippon Ink and Chemicals, Incorporated) Manufactured by ISHIHARA SANGYO KAISHA, LTD.) Glass beads were added to 270 parts by weight of a mill base and stirred for 6 hours by a paint shaker. To 594 parts by weight of the mill base were added 135 parts by weight of Bekkorite M-6154-40 (manufactured by Dainippon Ink and Chemicals, Inc.), Superbekkamin L-117-60 (butylated melamine resin, NV 60% Ltd.), 45 parts by weight of Super Bekkamin L-105-60 (methylated melamine resin NV 60%, manufactured by Dainippon Ink and Chemicals, Inc.) and 20 parts by weight of a thickener (sorbitoso 150 / cyclohexanone = 50/50) And the glass beads were filtered to obtain a preparation paint.

(Adjustment of Test Paint and Coating)

0.5% of an antifoaming agent (Furoren AC-300, manufactured by Kyoeisha Chemical Co., Ltd.)) was added to the prepared preparation paint, and 0.5% of the surface conditioner obtained in Examples 1 to 9 and Comparative Examples 1 to 6 1.5%, and the mixture was stirred with a mixer at 2000 rpm for 2 minutes to obtain a test paint as a baking type polyester paint. The obtained test paint was immediately coated on a substrate with a # 42 bar coater and immediately baked at 245 DEG C for 60 seconds (PMT: 225 DEG C) and cured to form a cured coating.

For comparison, the cured film prepared by using the surface conditioner of Comparative Example 6 was immersed in a 1% sulfuric acid aqueous solution for 24 hours to accelerate the hydrolysis to obtain a cured film obtained in Comparative Example 7 , And a cured film for comparison of hydrophilicity.

(Evaluation of Crater Phenomenon Occurring on Coin Coating)

The number of crater developments occurring per 10 cm 2 of the cured film was visually counted and evaluated according to the following evaluation criteria.

Criteria for evaluation of occurrence of crater phenomena

No occurrence of crater phenomenon: ◎

Approximately three places or less: ○

Approximately 7 places or less: ○ ~ △

More than 10 locations: △

Crater occurrence on entire surface: ×

(Evaluation of Leveling Property of Cured Coating Surface)

The surface state of the coated surface after curing was visually observed and evaluated in the following evaluation criteria are shown in Table 3 below.

Evaluation criteria for leveling property

Good: ○

There are a few coating lines on the bar coater: ○ ~ △

The coating line of the bar coater remains marked: △

Dent occurred: ×

(Measurement of Water Contact Angle of Cured Coating)

0.02 占 퐇 of water droplets were dropped onto the cured coating surface immediately after curing and the initial water contact angle was measured using a contact angle meter (Kyowa Interface Science Co., Ltd.). The results are shown in Table 3 below. Further, the water contact angle of the cured coating film of Comparative Example 7 was measured for hydrophilicity comparison

(Evaluation of actual curing of coating film)

The coated plate on which the hardened coating was formed on the surface was folded at an angle of 45 占 and was vertically erected. After exposure for 2 months toward the outdoor south, the degree of contamination was visually evaluated in accordance with the following evaluation criteria. The results are shown in Table 3 below.

Pollution evaluation standard

Good contamination and good: ○

There is some contamination: △

Pollution is severe: ×

[Table 3]

As clearly shown in Table 3, the cured coatings of Examples 1 to 9 had a smaller crater development amount and better leveling property as compared with the cured coatings of Comparative Examples 1 to 6, and the coating surface was smooth. In addition, the cured coatings of Examples 1 to 9 exhibited good hydrophilicity and antifouling properties, which were about the same as the cured coatings of Comparative Example 7 for comparison of the water contact angle, the contamination degree in the flash test, and the hydrophilicity.

(Evaluation of stability of the test paint over time)

The initial viscosity of the prepared test paint, the viscosity after storage at 40 ° C for 1 month and 2 months (B-type viscometer) was measured, and the results are shown in Table 4 below. The cured coating films were prepared at the initial stage and after storage at 40 ° C for one month, respectively, and the water contact angle was evaluated by the aforementioned water contact angle measurement method. The results are shown in Table 4 below. In Table 4, the water contact angles shown in Table 3 are described as initial water contact angles.

[Table 4]

As clearly shown in Table 4, the cured coatings using the test paints of Examples 1 to 9 had good stability over time and did not increase viscosity or gelation. Also, in the cured coating of the test paint kept at 40 占 폚 for one month, the water contact angle is almost the same as the initial water contact angle and shows good hydrophilicity. On the other hand, the cured films of Comparative Examples 1 to 7 had a high water contact angle or crater phenomenon, and the surface characteristics were insufficient.

(Industrial applicability)

The surface conditioner of the present invention is a surface conditioner that is applied to the surface of household electrical appliances or automobile exterior materials, daily necessities, building materials formed of materials of plastic, rubber, paper, wood, glass, metal, stone, cement, mortar and ceramics Based on the total weight of the coating composition.

Claims (4)

80.00 to 99.99 parts by weight of at least one acrylamide monomer selected from the group consisting of dimethyl (meth) acrylamides and diethyl (meth) acrylamides, a siloxy group having one-terminal (meth) (Meth) acrylate monomer and 0.01 to 20.00 parts by weight of a mono (meth) acrylate monomer containing at least a block isocyanate group, and at least one selected from the group consisting of (meth) acrylates containing hydroxyl groups, (Meth) acrylate monomer having a weight average molecular weight of 1,500 to 50,000, wherein at least 10 parts by weight of any one of the functional group-containing monomers is copolymerized with the acrylamide monomer and the siloxy group-containing mono A surface modifier characterized by imparting hydrophilicity to a surface of a coating film:
[Formula 1]

R ² represents a hydrogen atom or a methyl group; R ² represents an alkylene group of 1 to 10 carbon atoms; R ³ represents an alkyl group of 1 to 12 carbon atoms; and m represents a number of 2 to 150. A coating agent comprising the surface-conditioning agent according to claim 1 and a film-forming component. A coating film according to claim 2, wherein the film is formed by being coated on a substrate and cured. The film according to claim 3, wherein the film has antifouling property on the surface of the film due to the hydrophilicity.