JP2010031074A - Coating composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coating composition efficiently forming a glossy and beautiful coating surface having excellent water repellency, antifouling properties and forming a protective coating film by which a water scale can be removed by a simple operation such as water cleaning even if the water scale adheres to the coating surface and which maintains excellent glossiness, water repellency and antifouling properties for a long time on an application surface. <P>SOLUTION: In the coating composition including one or more organic solvents selected from an aliphatic hydrocarbon-based solvent, a petroleum-based solvent, an aromatic solvent, an alcohol and a fluorine-based solvent as a base, (a) a moisture-curable silicone resin, (b) a reaction promotor and (c) a reactive silicone oil having at least one reactive organic group at a side chain of the molecule thereof are contained in the base. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention can efficiently create a glossy and beautiful protective film with excellent water repellency and antifouling properties on, for example, painted surfaces of automobiles, and can be easily washed with water even if water stains adhere to it. The present invention relates to a coating composition that can be removed by work, and in particular, can form a protective film on the coated surface that maintains excellent water repellency and antifouling properties over a long period of time.

  Conventionally, for example, a coating composition for forming a protective film on a painted surface of an automobile includes a reactive silicone oil having a reactive organic group at both ends and a silicone oligomer that is cured by moisture in the air. (See, for example, Patent Documents 1 and 2).

However, the double-end reactive silicone oil, which is a glazing, antifouling and water repellent component in the compositions of Patent Documents 1 and 2, has a weak chemical bond because the binding moiety exists only at both ends of the molecule. However, it has been difficult to maintain performances such as glazing, antifouling and water repellency brought about by silicone oil over a long period of time.
JP 2008-75021 A JP 2008-138074 A

  The present inventors responded to the market need to maintain or restore the aesthetics of the painted surface with simpler maintenance, can be applied to the painted surface efficiently, and are glossy over a long period of time, such as antifouling and water repellency. As a result of intensive studies on a coating composition capable of maintaining the performance, the present invention has been completed.

  In other words, the present invention can produce a beautiful protective film that is efficiently excellent in water repellency and antifouling properties, for example, on painted surfaces of automobiles, etc. It is an object of the present invention to provide a coating composition that can be removed by simple operation, and in particular, can form a protective film that maintains excellent glossiness, water repellency and antifouling properties over a long period of time. It is what.

In order to achieve the above object, the present invention is based on one or more organic solvents selected from aliphatic hydrocarbon solvents, petroleum solvents, aromatic solvents, alcohols and fluorine solvents, During the base,
(A) a moisture curable silicone resin;
(B) a reaction accelerator;
(C) a reactive silicone oil having at least one reactive organic group in the side chain of the molecule;
The gist of the present invention is a coating composition characterized by containing

  In the coating composition of the present invention, (a) a moisture curable silicone resin, (b) a reaction accelerator, and (c) a reactivity having at least one reactive organic group in the side chain of the molecule. Because it contains silicone oil, for example, it can efficiently create a beautiful protective film with excellent water repellency and antifouling properties on the painted surface of automobiles, etc. It can be removed by simple operations such as washing with water, and in particular, it can form a protective film on the coated surface that maintains excellent glossiness, water repellency and antifouling properties over a long period of time. Obtainable.

  Hereinafter, the coating composition of the present invention (hereinafter simply referred to as the composition) will be described in more detail. The composition of the present invention is applied, for example, to a painted surface of an automobile, and as a base for dissolving or dispersing the components in the composition to form a uniform coating film, an aliphatic hydrocarbon solvent, One or more organic solvents selected from petroleum solvents, aromatic solvents, alcohols and fluorine solvents are used.

  Examples of such organic solvents include aliphatic hydrocarbon solvents such as hexane, heptane, nonane, decane, and undecane, petroleum solvents such as mineral spirit, aromatic solvents such as benzene, toluene, and xylene, 1,1 , 2,2,3,3,4-heptafluorocyclopentane, HFE, ethyl nonafluoroisobutyl ether, ethyl nonafluorobutyl ether, methyl nonafluoroisobutyl ether, methyl nonafluoroisobutyl ether, and the like. These solvents may be used alone or in combination of two or more.

  The composition of the present invention comprises (a) a moisture curable silicone resin, (b) a reaction accelerator, and (c) at least one reactive organic group in the side chain of the molecule in the base composed of the organic solvent. And a reactive silicone oil.

  The moisture curable silicone resin constituting the component (a) is, for example, a silicone alkoxy oligomer having a relatively low molecular weight that is blocked with an alkoxysilyl group represented by Si-OR at the molecular end, which will be described later (b). In the presence of a reaction accelerator, which is a component, alkoxysilyl groups are hydrolyzed by water in the air to form silanol groups (Si—OH), and the silanol groups are condensed with each other to form a siloxane bond (Si—O—Si). What has the property which forms can be mentioned as a preferable thing.

The moisture curable silicone resin having such properties is expressed by the following average composition formula.
R _m Si (OR ′) _n O _{(4-mn) / 2}
In the above formula, R is one or more groups selected from a substituted or unsubstituted alkyl group and an aryl group, and R ′ is an alkyl having a hydrogen atom and an ether bond having 1 to 4 carbon atoms. One or more groups selected from the group, and m and n are numbers satisfying the following relational expression.
0.5 ≦ m ≦ 1.8,
0.01 ≦ n ≦ 2.5 and 1 ≦ m + n ≦ 3

  The addition amount of the moisture curable silicone resin is 0.1 to 30 parts by weight, preferably 1 to 15 parts by weight with respect to 100 parts by weight of the composition of the present invention. If the amount is less than 0.1 weight, a uniform coating film cannot be obtained, and if it exceeds 30 parts by weight, the wiping operation may be adversely affected.

  The moisture curable silicone resin is available as a commercial product, for example, KR-500 (trade name) (manufactured by Shin-Etsu Chemical Co., Ltd.), KR-510 (trade name) (manufactured by Shin-Etsu Chemical Co., Ltd.), X- 40-3327 (trade name) (manufactured by Shin-Etsu Chemical Co., Ltd.), X-40-9225 (trade name) (manufactured by Shin-Etsu Chemical Co., Ltd.), etc. These water-curable silicone resins are used alone. Two or more types may be used in combination.

  The reaction accelerator as component (b) is an alkoxysilyl group represented by Si—OR ′ contained in the moisture curable silicone resin as component (a) (wherein R ′ represents a hydrogen atom and a carbon atom number). 1 or 2 or more groups selected from alkyl groups having 1 to 4 ether bonds) are components that promote the hydrolysis and condensation reaction with moisture in the air, and the component (b) By containing, the crosslinking density of the said (a) component increases, hardening progresses and a hard film can be obtained.

  Examples of the component (b) having such effects include organometallic compounds including aluminum, titanium and tin, inorganic acids such as sulfuric acid, hydrochloric acid, acetic acid and phosphoric acid, potassium hydroxide and sodium hydroxide. An amine compound such as alkali, ammonia, diethanolamine, and triethanolamine can be used.

  The component (b) can be obtained as a commercial product. For example, D-20 (trade name) (manufactured by Shin-Etsu Chemical Co., Ltd., containing titanium-based metal), DX-9740 (trade name) (Shin-Etsu Chemical Co., Ltd.) And X-40-2309A (trade name) (manufactured by Shin-Etsu Chemical Co., Ltd., containing phosphoric acid).

  (B) As addition amount of a component, 0.01-30 weight part is preferable with respect to 100 weight part of this composition, More preferably, it is 0.05-10 weight part. If the amount is less than 0.01 parts by weight, the reaction rate is slow, and thus the curability is low. If the amount exceeds 30 parts by weight, the antifouling property and the hardness of the coating film may be adversely affected.

  The reactive silicone oil which is the component (c) is an effective component for improving wiping workability due to a lubricating effect, antifouling property and water repellency. Further, since the reactive organic group of the silicone oil is firmly bonded to the moisture curable silicone resin forming the component (a) by chemical bonding, durability is considered to be improved.

  This reactive silicone oil is one in which at least one reactive organic group is bonded to the side chain of the molecule. Examples of the reactive organic group include an alkoxy group, a silanol group, a carbinol group, a carboxyl group, an amino group, Any of a hydrogen group, a diol group, an epoxy group, a methacryl group, a mercapto group, and a phenol group can be exemplified. This reactive silicone oil can be obtained as a commercial product. For example, KF-868 (amino-modified type, manufactured by Shin-Etsu Chemical Co., Ltd.) or X-22-4039 (carbinol-modified type, Shin-Etsu Chemical Co., Ltd.) Company-made).

  The reactive silicone oil preferably has a reactive organic group in the side chain of the molecule and has a monovalent hydrocarbon group at both ends of the molecule. Silicone oil has a molecular structure like a chain, and if it has a reactive organic group in the chain, chemical bonding is possible everywhere in the molecular chain. A strong coating is expected to be completed. For this reason, when such a reactive silicone oil is used, the reactive silicone oil can be fixed on the coating surface over a long period of time, and the effect of improving the antifouling property and water repellency can be obtained. it can.

  The amount of component (c) added is preferably 0.1 to 20 parts by weight, more preferably 0.5 to 10 parts by weight, based on 100 parts by weight of the composition. This is because if it is less than 0.1 part by weight, water repellency and antifouling properties cannot be expressed, and if it exceeds 30 parts by weight, the antifouling property and the hardness of the coating film may be adversely affected.

  Each component in the composition of the present invention is microencapsulated so that the component (a) and the component (b) or the component (a) and the component (c) are brought into a non-contact state and each component is stable. It can also be kept in a proper state. Specifically, a mononuclear capsule in which either the component (b) or the component (c) is microencapsulated as a core material, and a multinuclear capsule in which the components (a) and (b) are microencapsulated as a core material , Multinuclear capsules microencapsulated with the components (a) and (c) as core materials, or mononuclear capsules microencapsulated with the components (a), (b) and (c) as core materials, respectively. Can be mentioned.

  The size of the microcapsule is preferably 20 μm to 0.5 μm in diameter, more preferably 10 μm to 1 μm, and most preferably 2 μm to 3 μm. When the diameter of the microcapsule is smaller than 0.5 μm, it is difficult to produce the microcapsule, and there is a possibility that the microcapsule may be damaged during manufacture or handling. On the other hand, when it is larger than 20 μm, uniform dispersion becomes difficult.

  The wall material constituting the capsule wall of the microcapsule may be appropriately determined according to the core material to be encapsulated. For example, polyurethane, polyurea, gelatin, gum arabic, sodium alginate, ethyl cellulose, polyvinyl ether-maleic anhydride copolymer Styrene-maleic anhydride copolymer, polyethylene, polystyrene, paraffin wax and the like.

  The method of microencapsulation is not particularly limited, and is conventionally known as an encapsulation method, such as an interfacial polymerization method, a submerged cured coating method (chemical method), a phase separation method or an interfacial precipitation method (physicochemical method), A spray drying method, a spray cooling method, an air suspension coating method (physical method), or the like can be used.

  The composition of the present invention can also take a form containing fine powder for the purpose of forming a uniform coating film and improving workability such as application and wiping. The fine powder applied to the composition of the present invention preferably has an average particle size of 0.1 to 50 μm, more preferably 2 to 30 μm. When the average particle size of the fine powder to be added is less than 0.1 μm, there is a risk of difficulty in wiping work during construction, and when it is 50 μm or more, there is a risk of scratching the coating surface during wiping.

  The fine powder can be obtained as a commercial product, for example, techpolymer (manufactured by Sekisui Plastics Co., Ltd., PMMA fine powder), flow beads CL2080 (manufactured by Sumitomo Seika Co., Ltd., low density polyethylene resin powder), MSP3000 (manufactured by Nikko Rica Co., Ltd., silicone resin powder) and Eposter S (manufactured by Nippon Shokubai Co., Ltd., melamine / formaldehyde resin powder).

  Moreover, in order to distinguish the applied part and the non-executed part, or to prevent wiping from being left behind, a fine powder added with a pigment can also be suitably used. Examples of commercially available products include tuftic beads AR650 series (manufactured by Toyobo Co., Ltd., crosslinked acrylic resin powder), Art Pearl C-200, C-300, C-400, C-800 (manufactured by Negami Kogyo Co., Ltd., Cross-linked urethane fine powder).

  The amount of fine powder added is preferably 0.1 to 10 parts by weight with respect to 100 parts by weight of the composition. If the amount is less than 0.1 part by weight, the effect of improving the wiping work cannot be exhibited. If the amount exceeds 10 parts by weight, a uniform film may not be formed.

  The composition of the present invention can also take a form containing an organophilic layered clay mineral for the purpose of improving antifouling properties and decreasing the sedimentation rate of the fine powder in the composition. Examples of the organophilic layered clay mineral applied to the composition of the present invention include montmorillonite, mica and talc.

  Examples of the organophilic treatment method for the organophilic layered clay mineral include layer surface modification, end surface modification, or composite treatment thereof. Furthermore, examples of the organic treatment material include quaternary ammonium ions, anionic polymers, alkyltrialkoxysilanes, carboxyvinyl polymers, and highly polar organic solvents.

  The addition amount of the organophilic layered clay mineral is preferably 0.01 to 10 parts by weight, more preferably 0.5 to 5 parts by weight, with respect to 100 parts by weight of the composition. When the amount of the organophilic layered clay mineral is 0.01 parts by weight or less, the effect of improving the antifouling property and the effect of preventing sedimentation is low, and when it exceeds 10 parts by weight, the wiping workability may be adversely affected. is there.

  In addition to the composition of the present invention, additives such as an ultraviolet absorber, a fragrance, and a surfactant can be blended within a range that does not adversely affect the antifouling effect.

  When the composition of the present invention is applied to the painted surface of an automobile, a method of impregnating the composition into a sponge or cloth and rubbing the painted surface can be used. The application method can be selected according to the purpose and application, such as brush painting and coating with aerosol spray.

  Thus, when the composition of the present invention is applied to the painted surface, the base solvent is volatilized, and the moisture in the air and the component (b) promote the reaction of the component (a) and are applied to the painted surface. A cured film is formed. Furthermore, the reactive silicone oil of component (c) is chemically bonded to the cured film, so that gloss and gloss are imparted to the painted surface, and even if water stains adhere, it can be removed by simple operations such as washing with water. In addition, it is possible to form a coating on the coated surface that maintains excellent water repellency and antifouling properties over a long period of time.

  Further, in the case of a composition in which each component is microencapsulated, when the composition is applied to the coating surface as described above, the base solvent is volatilized and each component in the composition is subjected to pressure at the time of application. The capsule encapsulated in microcapsule is broken and the inclusions of the capsule are released. Along with this, moisture in the air and the component (b) promote the reaction of the component (a), and a cured film is formed on the painted surface. Furthermore, the reactive silicone oil of component (c) is chemically bonded to the cured film, so that gloss and gloss are imparted to the painted surface, and even if water stains adhere, it can be removed by simple operations such as washing with water. In addition, it is possible to form a coating on the coated surface that maintains excellent water repellency and antifouling properties over a long period of time.

  While showing the composition of each composition which concerns on Examples 1-3 shown in following Table 1, and Comparative Examples 1 and 2, antifouling property of each composition which concerns on Examples 1-3 and Comparative Examples 1 and 2 The water repellency was evaluated and the results were shown.

Evaluation of antifouling property (soil removal property) Each composition is uniformly applied with a urethane sponge to a white test piece defined in JIS K2396 (a polish coating agent for automobiles). A test piece is obtained by wiping the surface with a clean cloth after the surface has dried. After further drying for one day, the whiteness of each test piece is measured with a color tester HC-1 (manufactured by Suga Test Instruments Co., Ltd.), and the value is taken as the initial whiteness.

  As a contaminant, carbon black FW-200 (manufactured by Holbein Kogyo Co., Ltd., particle size: 0.002 to 0.028 μm) is uniformly dispersed in 5 parts by weight of water and 95 parts by weight of water. 0.5 MPa), and uniformly apply the surface of the test piece.

  The test piece is dried at 60 ° C. for 1 hour, baked with contaminants, and then allowed to cool to room temperature. After standing to cool, the contaminants adhering to the surface of the test piece are washed under running water while rubbing with a soft cloth such as gauze. This is one cycle. After removing moisture from the test piece, the whiteness is measured with a color tester HC-1 (manufactured by Suga Test Instruments Co., Ltd.) to obtain the whiteness after washing. The initial performance of the soil removal property is evaluated based on the measured value when one cycle of the test is performed.

Evaluation criteria The soil removability is obtained by the following formula.
Dirt removal property = initial whiteness-whiteness after washing

The evaluation criteria for dirt removal are as follows.
○: 0 ≦ stain removal <1.0
□: 1.0 ≦ dirt removal property <3.0
Δ: 3.0 ≦ Dirt removal property <5.0
×: 5.0 ≦ Dirt removal

Durability of stain removal The evaluation of the antifouling property is evaluated by the stain removal property after 10 cycles. What are the evaluation criteria and evaluation methods? The same as the above-described dirt removal property.

Water Repellency Each of the prepared compositions was impregnated with a sponge in an automobile bonnet, and then uniformly applied and dried for 10 minutes. After drying, the surface was wiped with a clean towel (30 × 30 cm). After further drying for 1 day, water was applied to confirm the water-repellent state. The water repellent state was evaluated according to the following criteria.

○: Water repellent well Mouth: Water repellent △: Slightly water repellent ×: Little water repellent

Durability of water repellency After running for 3 months, after washing with water, water was applied to evaluate water repellency. The evaluation method is the same as the aforementioned water repellency evaluation standard.

  From Table 1, in the compositions of Comparative Examples 1 and 2, the stain removability was x or Δ, and the water repellency after 3 months was x or □. On the other hand, in each of the compositions of Examples 1 to 3, it was confirmed that the dirt removal durability was □, and the water repellency after 3 months was evaluated as ◯. It was.

Claims (6)

Based on one or more organic solvents selected from aliphatic hydrocarbon solvents, petroleum solvents, aromatic solvents, alcohols and fluorine solvents,
(A) a moisture curable silicone resin;
(B) a reaction accelerator;
(C) a reactive silicone oil having at least one reactive organic group in the side chain of the molecule;
A coating composition comprising:   At least one reactive organic group bonded to the side chain of the molecule of the reactive silicone oil is an alkoxy group, silanol group, carbinol group, carboxyl group, amino group, hydrogen group, diol group, epoxy group, methacryl group. The coating composition according to claim 1, wherein the coating composition is any one of, a mercapto group, and a phenol group.   The coating composition according to claim 1, wherein both ends of the reactive silicone oil are monovalent hydrocarbon groups.   0.1 to 30 parts by weight of component (a), 0.01 to 30 parts by weight of component (b), and 0.1 to 20 parts by weight of component (c) with respect to 100 parts by weight of the composition The coating composition according to any one of claims 1 to 3, further comprising:   The coating composition according to any one of claims 1 to 4, which comprises 0.1 to 10 parts by weight of fine powder having an average particle size of 0.1 to 50 µm with respect to 100 parts by weight of the composition. object.   The coating composition according to any one of claims 1 to 5, which comprises 0.01 to 10 parts by weight of a layered clay mineral that has been subjected to an organophilic treatment with respect to 100 parts by weight of the composition.