Antifouling coating with comb structure on surface and preparation method thereof

Abstract

The application provides an antifouling coating with a surface having a comb structure and a preparation method thereof. The antifouling coating comprises a component A, a component B and a component C. According to the raw material composition by weight, the component A comprises 20-40 parts of a hydroxyl silicone resin, 5-10 parts of a small molecule silicon oil, 10-20 parts of hydrophobic nano silicon dioxide, 10-20 parts of an antifouling active molecule, 3-5 parts of a pigment, 10-20 parts of a solvent and 3-5 parts of a thixotropic agent. The component B comprises 1-5 parts of a crosslinking agent, 0.1-0.5 parts of a catalyst and 5-10 parts of a solvent. The component C comprises 10-20 parts of a long-chain fluorine-containing silane coupling agent, 60-80 parts of an alcohol solvent and 6-8 parts of deionized water. The preparation method of the antifouling coating comprises the following steps: mixing the component A and the component B, coating the mixed solution on a substrate, spraying the component C on the surface of the antifouling coating which is not completely cured, and curing to obtain the antifouling coating. The antifouling coating has a comb-like fluff structure, further strengthens the super-hydrophobic property of the coating, and realizes better drag reduction and antifouling effect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of super-hydrophobic drag-reducing antifouling coating preparation, in particular to an antifouling coating with a comb structure on the surface and a preparation method thereof. BACKGROUND

[0002] Ship resistance is one of the most important overall performance indicators of a ship, and has a significant impact on the technical and economic performance of the ship. Ship drag reduction is directly related to the extension of the sailing distance, the improvement of the speed, and the reduction of the operating fuel consumption. Limiting carbon emissions forces the shipping industry, which accounts for more than 90% of global freight volume, to pursue the reduction of sailing resistance even more. In recent years, international conferences on ship emission reduction have been frequently held. The shipping industry has reached a consensus that the frictional resistance, which accounts for 50% of the total resistance, is more valuable and has more potential to reduce than the shape resistance and wave-making resistance. Therefore, the antifouling coating with good drag-reducing performance has a broad market promotion prospect.

[0003] The current drag reduction technology mainly focuses on constructing surface microstructure drag reduction or super-hydrophobic surface drag reduction, mostly using organic silicone resin as the base material for antifouling drag reduction coating structure design. Patent 201410194045.7 discloses a two-component drag reduction coating composition suitable for marine environment, which uses organic silicon two-component curing technology, adds surfactants and lubricants in the coating formula, and realizes the drag reduction effect of the coating through the self-lubricating effect of the cured coating. Patent 201410308738.4 discloses a self-adaptive microstructure antifouling drag reduction material and its preparation method, which uses conventional deep silicon etching method to etch single crystal silicon wafer by plasma etching, controls the etching depth of 30-90 microns, and prepares single crystal silicon wafer with sawtooth-shaped recess pattern. Then, using organic silicone elastomer as the base material, a drag reduction coating with regular sawtooth-shaped array structure is prepared on the surface of the base material by inverse molding method. Patent 202310723588.2 discloses a multifunctional bionic structure surface and its preparation method, which designs an epoxy drag reduction coating with added drag reduction agent and micron-level bionic structure on the surface, and a preparation method. First, apply the drag reduction coating on the surface of the substrate, then paste the release film with arrayed bionic structure on the surface of the drag reduction coating which is not completely cured, and then remove the release film after the surface of the drag reduction coating is cured. The surface of the release film has a layer of silicone oil, and the surface of the drag reduction coating obtains a synergistic drag reduction coating with micron-level circular groove structure. Patent 202111224860.X discloses a preparation method of super-hydrophobic antifouling drag reduction material, which learns from the microstructure of the small locust leaf surface and designs the structure of the super-hydrophobic antifouling drag reduction material. First, prepare a bionic "claw-shaped" structure substrate using high molecular substances as raw materials, then treat the bionic "claw-shaped" structure substrate by combining chemical plating with electrodeposition to metalize its surface and prepare a multi-level multi-scale "millimeter-micron-nanometer" multi-level structure on it, and finally modify it by long-chain alkane acid soaking method to make it have hydrophobic properties, thus obtaining a super-hydrophobic antifouling drag reduction material. The multi-level multi-scale "millimeter-micron-nanometer" multi-level structure and the hydrophobic properties of long-chain alkane acid work together to achieve the super-hydrophobic properties of the super-hydrophobic antifouling drag reduction material, thus achieving the purpose of antifouling and drag reduction. Patent 201710733098.5 discloses a preparation method of self-repairing super-hydrophobic drag reduction elastomer film, which uses polydimethylsiloxane elastomer or polyurethane elastomer to prepare an elastomer with shark skin surface groove structure, and uses polyacrylamide / polyfluoroalkyl acrylate block copolymer to form a micro-nano structure similar to the surface of lotus leaf on the surface of the elastomer. Patents 201210110100.0, 202311573392.6, 202310446583.X, 201911076294.5, etc. modify nano-silicon dioxide to be super-hydrophobic, then compound it with low surface energy resin to construct a rough surface with micro-nano dual structure, form a super-hydrophobic coating, and achieve the effect of drag reduction.

[0004] The microstructure is generally in a static state, although the microstructure drag reduction has a certain effect in the initial use, but the marine environment is complex and changeable, once the marine fouling organisms adhere to the surface, the surface microstructure is easily damaged, the coating will lose the drag reduction effect, in addition, the existing antifouling coating preparation, the preparation process is not only complicated, but also cannot take into account the super-hydrophobic and long-acting antifouling. SUMMARY

[0005] Therefore, the present application aims to provide an antifouling coating with a comb structure and a preparation method thereof, to solve the problem that the microstructure in the prior art is generally in a static state, although the microstructure drag reduction has a certain effect in the initial use, but the marine environment is complex and changeable, once the marine fouling organisms adhere to the surface, the surface microstructure is easily damaged, the coating will lose the drag reduction effect, in addition, the existing antifouling coating preparation, the preparation process is not only complicated, but also cannot take into account the super-hydrophobic and long-acting antifouling.

[0006] To achieve the above object, the technical scheme of the present application is as follows:

[0007] A preparation method of an antifouling coating with a comb structure, the antifouling coating being a super-hydrophobic biomimetic drag reduction antifouling coating, comprising a component A, a component B and a component C;

[0008] The component A comprises the following raw materials in parts by weight: hydroxy silicone resin 20-40 parts, small molecule silicone oil 5-10 parts, hydrophobic nano-silicon dioxide 10-20 parts, antifouling active molecules 10-20 parts, pigments 3-5 parts, solvents 10-20 parts, and thixotropic agents 3-5 parts;

[0009] The component B comprises the following raw materials in parts by weight: cross-linking agent 1-5 parts, catalyst 0.1-0.5 parts, and solvent 5-10 parts;

[0010] The component C comprises the following raw materials in parts by weight: long-chain fluorine-containing silane coupling agent 10-20 parts, alcohol solvent 60-80 parts, and deionized water 6-8 parts;

[0011] The preparation method of the antifouling coating comprises the following steps:

[0012] The component A and the component B are mixed according to a mass ratio of 8-12:1, preferably 10:1, and then stirred uniformly, the mixed solution is coated on the substrate, and then cured for 5-15 minutes, preferably 10 minutes, the component C is sprayed on the surface of the antifouling coating which is not completely cured, and the antifouling coating with a comb structure is obtained after complete curing.

[0013] The present application sprays long-chain fluorine-containing silane coupling agent on the surface of the incompletely cured silicone coating, and realizes the preparation of a comb-type fluff structure on the surface of the silicone coating by the reaction of the long-chain fluorine-containing silane coupling agent with the hydroxyl groups contained in the surface layer resin during the hydrolysis process of the long-chain fluorine-containing silane coupling agent, the comb-type fluff structure is nanoscale, which not only strengthens the super-hydrophobic property of the coating, but also is in a dynamic state in the marine environment, so that marine fouling organisms are not easy to adhere to the surface, and the drag reduction and antifouling effect of the coating is further enhanced; in addition, small molecule silicone oil and antifouling active molecules are added to the resin system, the long-acting antifouling effect is realized by the exuding action of the small molecule silicone oil and the antifouling active molecules, and hydrophobic nano-silicon dioxide is introduced into the formula to form a micro-nano structure on the surface of the coating, so that the super-hydrophobicity of the coating is realized, that is, the super-hydrophobicity and long-acting antifouling effect of the present application are realized; and the preparation method is simple, can be prepared in large area, the raw materials are abundant in source and low in price, and the economic benefit is remarkable.

[0014] Further, the coating process includes one of brushing, roller coating, high-pressure airless spraying, air spraying and the like construction processes.

[0015] Further, the preparation methods of the A component and the B component are both high-speed dispersion methods.

[0016] The setting can improve the mixing uniformity of the A component and the B component.

[0017] Further, the preparation method of the A component includes the following steps:

[0018] The hydroxyl silicone resin, the small molecule silicone oil, the hydrophobic nano-silicon dioxide, the antifouling active molecule, the pigment and the solvent are added to a dispersion draw cylinder, and are high-speed dispersed for 30 minutes under a certain rotating speed, then the thixotropic agent is added, and the high-speed dispersion is continued for 2 hours, and when the fineness of the coating is reduced to below 80 microns, the material can be filtered out.

[0019] Further, the preparation method of the B component includes the following steps:

[0020] The crosslinking agent, the catalyst and the solvent are added to the draw cylinder, and are high-speed dispersed for 5 minutes under a certain rotating speed, and then the material can be discharged after being uniformly dispersed.

[0021] Further, the rotating speed of the A component and the B component is 1000-2000 revolutions per minute.

[0022] Further, the preparation method of the C component includes the following steps:

[0023] The long-chain fluorine-containing silane coupling agent, the alcohol solvent and the deionized water are added to a dispersion container, and are stirred and dispersed uniformly for use. The long-chain fluorine-containing silane coupling agent hydrolysis solution needs to be prepared and used immediately, and the applicable period cannot exceed 2 hours.

[0024] Further, the long-chain fluorine-containing silane coupling agent is one or more of heptadecafluorodecyltrimethoxysilane, heptadecafluorodecyltriethoxysilane, tridecafluorooctyltrimethoxysilane, and tridecafluorooctyltriethoxysilane.

[0025] Further, the anti-fouling coating has a molecular formula of:

[0026]

[0027] wherein n>1.

[0028] Further, the anti-fouling active molecule is metomidine.

[0029] Further, the hydroxyl silicone resin is a silicone resin with hydroxyl groups at both ends of the molecular chain, and the viscosity of the hydroxyl silicone resin is 2800-20000 cP, specifically, the resin viscosity is one or more of 2800 cP, 5000 cP, 10000 cP, and 20000 cP.

[0030] Further, the small-molecule silicone oil is one or more of methyl silicone oil or phenylmethyl silicone oil, and the viscosity of the small-molecule silicone oil is 50-300 cP.

[0031] Further, the hydrophobic nano-silica has a particle size of 20-300 nm, and the hydrophobic nano-silica is a long-chain alkyl grafted modified hydrophobic nano-silica, which is a raw material available in the prior art.

[0032] Further, the pigment is one or more of titanium dioxide, toluidine red, permanent red, iron black, carbon black, red iron oxide, and phthalocyanine blue.

[0033] Further, the thixotropic agent is one or more of polyamide wax, organic bentonite, and fumed silica.

[0034] Further, the solvent of the A component and the B component is one or more of xylene, butyl acetate, cyclohexanone, ethyl acetate, n-butanol, and isopropyl alcohol.

[0035] Further, the alcohol solvent of the C component is one or more of methanol, ethanol, and isopropyl alcohol.

[0036] Further, the cross-linking agent is one or more of ethyl silicate 28, ethyl silicate 32, and ethyl silicate 40.

[0037] Further, the catalyst is one or more of stannous octoate and dibutyltin dilaurate.

[0038] Compared with the prior art, the preparation method of the anti-fouling coating has the following advantages:

[0039] (1) The present application realizes the preparation of a comb-type bristle structure on the surface of the silicone coating by spraying a long-chain fluorine-containing silane coupling agent on the surface of the incompletely cured silicone coating, and the long-chain fluorine-containing silane coupling agent reacts with the hydroxyl groups contained in the surface layer resin during the hydrolysis process, so that a comb-type bristle structure is realized on the surface of the silicone coating, the comb-type bristle structure is nanoscale, not only strengthens the super-hydrophobic property of the coating, but also is in a dynamic state in the marine environment, so that marine fouling organisms are not easy to adhere to the surface, and the drag reduction and antifouling effect of the coating is further enhanced;

[0040] (2) The present application uses a low-surface-energy silicone resin as a base material, and in the formula design, small-molecule silicone oil and antifouling active molecules are added to the resin system, the long-acting antifouling effect is realized by using the exuding effect of the small-molecule silicone oil and the antifouling active molecules, and at the same time, hydrophobic nano-silicon dioxide is introduced into the formula to form a micro-nano structure on the surface of the coating, and the super-hydrophobicity of the coating is realized.

[0041] (3) The preparation method of the antifouling coating of the present application can realize the large-area preparation of the biomimetic drag reduction and antifouling coating, the coating construction process is simple, the raw materials are abundant in source and low in price, and the economic benefit is remarkable.

[0042] The present application also provides an antifouling coating with a comb-type structure on the surface, which is obtained by the above-mentioned preparation method.

[0043] The antifouling coating with a comb-type structure on the surface has the same advantages as the preparation method of the above-mentioned antifouling coating relative to the prior art, and will not be described here. BRIEF DESCRIPTION OF DRAWINGS

[0044] Figure 1 It is a structure diagram of the contact angle of the antifouling coating with a comb-type structure on the surface of the present application;

[0045] Figure 2 It is a drag performance diagram of the antifouling coating with a comb-type structure on the surface of the present application at different rotating speeds;

[0046] Figure 3 It is a schematic diagram of a glass piece coated with the antifouling coating of Example 1 of the present application in a navicula liquid after one week;

[0047] Figure 4 It is a schematic diagram of a glass piece coated with the antifouling coating of Example 1 of the present application in a navicula liquid after one week;

[0048] Figure 5 It is an atomic force microscope diagram of the antifouling coating with a comb-type structure on the surface of Example 1 of the present application;

[0049] Figure 6 It is a molecular structure diagram of the antifouling coating with a comb-type structure on the surface of the present application. DETAILED DESCRIPTION

[0050] In order to make the above objectives, characteristics and advantages of the present application more apparent, a specific embodiment of the present application is described in detail below with reference to the accompanying drawings.

[0051] Example 1

[0052] A preparation method of a super-hydrophobic biomimetic anti-fouling coating with a comb structure on the surface, the anti-fouling coating being an ultra-hydrophobic biomimetic anti-fouling coating, comprising a component A, a component B and a component C, and the raw material composition according to weight parts is as follows:

[0053] The preparation method of the component A is as follows: hydroxyl silicone resin, dimethyl silicone oil, hydrophobic nano-silica, metomidine, red iron oxide and dimethylbenzene are high-speed dispersed at 1000 rpm for 30 min, then fumed silica is added and high-speed dispersed for 2 h, and then the coating is filtered out when the fineness is reduced to 70 μm; wherein the particle size of the hydrophobic nano-silica is 20 nm.

[0054] The preparation method of the component B is as follows: ethyl silicate 28, dibutyltin dilaurate and dimethylbenzene are added into a cylinder and high-speed dispersed at 1000 rpm for 5 min, and then the material is discharged when it is uniformly dispersed.

[0055] The preparation method of the component C is as follows: heptadecafluorodecyltrimethoxysilane, methanol and deionized water are added into a dispersion container and stirred and dispersed uniformly for use. The long-chain fluorine-containing silane coupling agent hydrolysate needs to be prepared and used immediately, and the applicable period cannot exceed 2 hours.

[0056] The preparation method of the anti-fouling coating comprises the following steps:

[0057] The component A and the component B are mixed according to the mass ratio of 10:1, and then stirred uniformly, and then construction is performed, and the brush coating construction process can be used for construction, the brush coating base is the commonly used material of a ship, which can be selected according to needs, the long-chain fluorine-containing silane coupling agent pre-hydrolysate is sprayed on the surface of the anti-fouling coating which is not completely cured after the components A and B are mixed and cured for 10 min, and then the anti-fouling coating with a comb structure on the surface is obtained after the coating is completely cured.

[0058] Example 2

[0059] A preparation method of a super-hydrophobic biomimetic anti-fouling coating with a comb structure on the surface, the anti-fouling coating being an ultra-hydrophobic biomimetic anti-fouling coating, comprising a component A, a component B and a component C, and the raw material composition according to weight parts is as follows:

[0060] The preparation method of component A is as follows: hydroxyl organosilicon resin, dimethyl silicone oil, hydrophobic nano silica, metoimidine, toluidine red, and xylene are dispersed at a high speed of 1500 rpm for 30 min, then fumed silica is added, and high-speed dispersion is continued for 2 h. When the fineness of the coating is reduced to 50 μm, it can be filtered out.

[0061] The preparation method of component B is as follows: Ethyl silicate 32, stannous octoate and xylene are added to the mixing tank and dispersed at high speed at 1500 rpm for 5 minutes. After the material is evenly dispersed, it can be discharged.

[0062] The preparation method for component C is as follows: add heptadecafluorodecyltriethoxysilane, ethanol, and deionized water to a dispersion container, stir and disperse evenly before use. The hydrolysate of long-chain fluorinated silane coupling agents must be prepared and used immediately; its pot life should not exceed 2 hours.

[0063] The method for preparing the antifouling coating includes the following steps:

[0064] Mix components A and B at a mass ratio of 10:1. After stirring evenly, the coating can be applied by brushing. After the mixture of components A and B has cured for 15 minutes, spray a long-chain fluorinated silane coupling agent pre-hydrolysis solution onto the surface of the incompletely cured antifouling coating. Wait for the coating to fully cure to obtain an antifouling coating with a comb-like structure on the surface.

[0065] Example 3

[0066] A method for preparing an antifouling coating with a comb-like surface structure, wherein the antifouling coating is a superhydrophobic biomimetic drag-reducing antifouling coating, comprising component A, component B, and component C, and the raw materials are composed of the following components according to their weight parts: Table 1 below shows the formulation composition.

[0067] The preparation method of component A is as follows: hydroxyl organosilicon resin, benzyl silicone oil, hydrophobic nano silica, metoimidine, carbon black, and butyl acetate are dispersed at a high speed of 2000 rpm for 30 min, then fumed silica is added, and high-speed dispersion is continued for 2 h. When the fineness of the coating is reduced to 40 μm, it can be filtered out.

[0068] The preparation method of component B is as follows: Ethyl silicate 40, dibutyltin dilaurate, and xylene are added to the mixing tank and dispersed at high speed at 2000 rpm for 5 minutes. After the material is evenly dispersed, it can be discharged.

[0069] The preparation method for component C is as follows: add tridecafluorooctyltriethoxysilane, isopropanol, and deionized water to a dispersion container, stir and disperse evenly before use. The hydrolysate of long-chain fluorinated silane coupling agents must be prepared and used immediately; its pot life should not exceed 2 hours.

[0070] The preparation method of the antifouling coating comprises the following steps:

[0071] The components A and B are mixed according to a mass ratio of 10:1, and after stirring uniformly, the construction can be carried out, and the brush coating construction process can be used for construction. After the components A and B are mixed and cured for 20 minutes, the long-chain fluorine-containing silane coupling agent pre-hydrolysis solution is sprayed on the surface of the antifouling coating which is not completely cured, and after the coating is completely cured, the antifouling coating with a comb structure on the surface is obtained.

[0072] Table 1 Formulation of Examples 1-3

[0073]

[0074]

[0075] Performance test

[0076] (1) The comb-shaped silicone coating is prepared on a glass sheet, and the contact angle is tested, and the test results are as shown in Table 1. Figure 1

[0077] As can be seen from Table 1, the contact angle of the comb-shaped silicone coating developed is 155°, which is greater than 150°, and exhibits super-hydrophobic properties. Figure 1

[0078] (2) According to GB / T 7791-2014 “Antifouling paint drag reduction performance test method”, the drag performance of the traditional silicone coating and the comb-shaped silicone drag reduction coating of the present application at different rotating speeds is tested, the traditional silicone coating uses hydroxyl silicone resin as component A resin, and is cured with ethyl silicate, and the test data are as shown in Table 2. Figure 2

[0079] As can be seen from Table 2, the comb-shaped antifouling coating developed in the present application has a significant drag reduction effect compared with the traditional silicone coating. In the range of 5-25 revolutions per minute, the rotational resistance of the comb-shaped silicone drag reduction coating developed is lower than that of the traditional silicone coating, and the average drag reduction rate can reach about 10%. Figure 2

[0080] (3) The anti-algae performance test of the comb-shaped antifouling coating is carried out, and the boat-shaped algae is used as the experimental object. The blank glass sheet and the glass sheet coated with the comb-shaped antifouling coating are added into the boat-shaped algae liquid respectively, and are cultured in the light incubator. After one week, the adhesion of the boat-shaped algae on the surface of the coating is observed under the inverted fluorescence microscope, and the experimental data are as shown in Table 3 and Table 4. Figure 3 Figure 4

[0081] Figure 3 Figure 4 ​​​​​​​​It can be seen that a large number of navicula algae are attached to the blank glass sheet, and the glass sheet coated with the anti-fouling coating with the comb structure basically has no navicula algae attached after being cultured for one week, which indicates that the anti-fouling coating with the comb structure prepared by the method can obviously inhibit the attachment of navicula algae and has good anti-fouling performance.

[0082] (4) The surface of the prepared anti-fouling coating with the comb structure is analyzed by using an atomic force microscope, and the test results are as follows Figure 5 Figure 5 It can be found from the figure that the surface of the coating forms a regular comb columnar structure, the diameter of the columnar protrusions is about 200-600 nm, and the height is about 80 nm. It is indicated that spraying the long-chain fluorine-containing silane coupling agent pre-hydrolysis solution on the surface of the anti-fouling coating which is not completely cured can realize the comb structure on the surface.

[0083] Although the present application has been disclosed as above, the present application is not limited to this. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present application, and the protection scope of the present application should be subject to the scope defined by the claims.​

Claims

1. A method for preparing an antifouling coating with a comb-like structure on its surface, wherein the antifouling coating is a superhydrophobic biomimetic drag-reducing antifouling coating, characterized in that, Includes component A, component B, and component C; The A component comprises the following raw materials in parts by weight: 20-40 parts of hydroxyl silicone resin, 5-10 parts of small molecule silicone oil, 10-20 parts of hydrophobic nano silica, 10-20 parts of antifouling active molecule, 3-5 parts of pigment, 10-20 parts of solvent, and 3-5 parts of thixotropic agent; wherein the antifouling active molecule is metomididine. The B component comprises the following raw materials in parts by weight: 1-5 parts of crosslinking agent, 0.1-0.5 parts of catalyst, and 5-10 parts of solvent; The C component comprises the following raw materials in parts by weight: 10-20 parts of long-chain fluorinated silane coupling agent, 60-80 parts of alcohol solvent, and 6-8 parts of deionized water; the long-chain fluorinated silane coupling agent is one or more selected from heptadecafluorodecyltrimethoxysilane, heptadecafluorodecyltriethoxysilane, tridecafluorooctyltrimethoxysilane, and tridecafluorooctyltriethoxysilane; the alcohol solvent of the C component is one or more selected from methanol, ethanol, and isopropanol. The method for preparing the antifouling coating includes the following steps: Mix components A and B at a mass ratio of 8 to 12:

1. After stirring evenly, apply the mixture to the substrate and cure for 5 to 15 minutes. Then, spray component C onto the incompletely cured antifouling coating surface. After complete curing, an antifouling coating with a comb-like structure is obtained. The molecular formula of the antifouling coating is: ， Where n > 1.

2. The preparation method according to claim 1, characterized in that, The hydroxyl-containing silicone resin is a silicone resin with hydroxyl groups at both ends of its molecular chain, and the viscosity of the hydroxyl-containing silicone resin is 2800~20000 cP.

3. The preparation method according to claim 1, characterized in that, The small molecule silicone oil is one or more of methyl silicone oil or benzyl silicone oil, and the viscosity of the small molecule silicone oil is 50-300 cP.

4. The preparation method according to claim 1, characterized in that, The pigment is one or more of titanium dioxide, toluidine red, permanent red, iron black, carbon black, iron oxide red, and phthalocyanine blue.

5. The preparation method according to claim 1, characterized in that, The thixotropic agent is one or more of polyamide wax, organobentonite, and fumed silica.

6. The preparation method according to claim 1, characterized in that, The solvents for both component A and component B are one or more of xylene, butyl acetate, cyclohexanone, ethyl acetate, n-butanol, and isopropanol.

7. A stain-resistant coating with a comb-shaped structure on its surface, characterized in that, It is obtained by any one of the preparation methods according to claims 1 to 6.

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