JP5760210B2 - Coating agent and method for forming coating film - Google Patents

Description

  The present invention relates to a coating agent and a method for forming a coating film.

  In coating agents that are applied to the surface of electronic parts such as motor bearings, textile products, and leather products to impart oil repellency, fluoropolymers having perfluoroalkyl groups are often used from the viewpoint of excellent oil repellency. Yes.

  For example, Patent Document 1 discloses that a monomer having a perfluoroalkyl group or a perfluoropolyether group and having a carbon-carbon double bond and a monomer having a carbon-carbon double bond that does not contain fluorine. A coating agent having a fluorocopolymer obtained by polymerization as a main component has been proposed.

JP 2006-299016 A

  When applying a water / oil repellent treatment to the surface of a product or component (base material) using a coating agent mainly composed of a fluoropolymer as described above, before applying the coating agent to the surface of the base material. In addition, it is common to clean and remove dirt components such as fats and oils adhering to the surface of the substrate using a solvent. Normally, when an oil repellent is applied to a soiled substrate, it cannot be repelled to form a film, and the dirt and the oil repellent become a sea-island-like film. And oil repellency is not obtained. That is, if the coating agent is applied without performing the substrate cleaning process, a coating film having oil repellency may not be formed.

  However, when performing such a cleaning process, it is necessary to dry the substrate after the cleaning process, or to dispose of the solvent after the cleaning process, etc., and to impart oil repellency to the substrate. In addition to the work time required, there was a problem that the cost was high.

In general, fluoropolymers are highly transparent and have a thin coating thickness when used as a coating agent. Therefore, it is difficult to confirm whether or not a desired coating film is formed at a predetermined site. The coating agent is made to contain a coumarin-based fluorescent agent or a coloring agent to impart visibility to the coating film.
However, when a fluorescent agent or the like is added to a conventional coating agent containing a fluoropolymer, it may precipitate, particularly under low temperature conditions, and it is difficult to impart sufficient visibility to the coating film. It was.

  The present invention has been completed based on the above-described circumstances, and does not require a cleaning treatment of the base material before performing the oil-repellent treatment, and can form a coating film having high visibility even at low temperatures. It is an object to provide a coating agent and a method for forming a coating film.

As a result of intensive studies to solve the above problems, the following knowledge was obtained.
(A) By including two kinds of specific fluorocopolymers and a specific amount of an organic solvent, the base material can be provided with oil repellency without performing a cleaning process prior to the oil-repellent process.
(B) A coating agent containing two specific fluorine-based copolymers and a specific organic solvent of 25% by mass or more based on the total mass of components other than the dye is sufficient for a coating film even under low temperature conditions. An amount of fluorescent dye or colored dye capable of imparting visibility can be dissolved.
The present invention is based on such novel findings.

That is, in the present invention, the fluorine-containing monomer represented by the following general formula (1) is 60% by mass to 99% by mass and the (meth) acrylic acid ester represented by the following general formula (2) is 1% by mass to 40% by mass. % Or less and a fluorine-containing monomer represented by the following general formula (1) is represented by the following general formula (3): 20% by mass to 50% by mass Fluorine copolymer B obtained by polymerizing 50% by mass or more and 80% by mass or less of (meth) acrylic acid ester, an organic solvent selected from an ester solvent and an aromatic solvent, a fluorescent dye, and a coloring dye And the amount of the organic solvent is 25% by mass or more based on the total mass of components other than the dye.

（式中、Ｒ_１は水素又はメチル基であり、ｍは０〜４の整数、ｎは１〜１０の整数を示す。）

(In the formula, R ₁ is hydrogen or a methyl group, m is an integer of 0 to 4, and n is an integer of 1 to 10.)

（式中、Ｒ_１は水素又はメチル基であり、Ｒ_２は炭素数１〜４の直鎖アルキル基または分岐アルキル基を示す。）

(In the formula, R ₁ represents hydrogen or a methyl group, and R ₂ represents a linear alkyl group or branched alkyl group having 1 to 4 carbon atoms.)

（式中、Ｒ_１は水素又はメチル基であり、Ｒ_３は炭素および水素からなる環状部分を有する官能基を示す。）
また、本発明は、上記コーティング剤を用いるコーティング膜の形成方法である。

(In the formula, R ₁ represents hydrogen or a methyl group, and R ₃ represents a functional group having a cyclic portion composed of carbon and hydrogen.)
Moreover, this invention is a formation method of the coating film which uses the said coating agent.

  By coating the base material with a coating agent using two types of specific fluorine-based copolymers (fluorine copolymer A and fluorine-based copolymer B), the substrate can be coated without any cleaning treatment. The oil repellency can be imparted for the following reasons.

  When the coating agent of the present invention is applied to the surface of the substrate, the coating agent is mixed with a soil component such as oil or fat existing on the surface of the substrate. In the process of forming the coating film by drying the coating agent, the soil component on the substrate surface is pushed out of the coating film, and the fluorine-based copolymer A having excellent oil repellency appears on the surface side of the coating film, It is thought to impart oil repellency to the substrate.

  Specifically, when the coating agent is applied to the substrate, the stain component is once dissolved in the solvent contained in the coating agent, but since the fluorine-based copolymer B has low compatibility with the stain component, the stain component is placed outside. Retreat to form the base of the coating film, while the fluorocopolymer A moves to the surface side of the coating film (bleeds out) to form an oil-repellent film. As a result, according to the present invention, it is possible to provide a method for forming a coating film and a coating agent that do not require the cleaning treatment of the substrate before the oil repellent treatment.

Further, according to the present invention, although the details of the reason are unclear, the total mass of two specific fluorine-based copolymers (fluorine-based copolymer A and fluorine-based copolymer B) and components other than the dye By adding 25% by mass or more of an organic solvent, it is possible to dissolve fluorescent dyes and colored dyes in an amount that can provide sufficient visibility to the coating film even under low temperature conditions. A highly visible coating film can be formed.

This invention is good also as the following structures The ratio of 5 to 30 mass% of said fluorocopolymer A with respect to the total mass of said fluorocopolymer A and said fluorocopolymer B May be included.
With such a configuration, a coating film having excellent oil repellency after being placed in a high temperature state can be formed.

The organic solvent may contain butyl acetate.
With such a configuration, various fluorescent dyes and colored dyes have high solubility, and the solubility of the fluorinated copolymer A and the fluorinated copolymer B is also excellent.

  ADVANTAGE OF THE INVENTION According to this invention, the washing | cleaning process of the base material before performing an oil-repellent process is unnecessary, and the formation method of a coating agent and a coating film which can form a coating film with high visibility also under low temperature can be provided. .

The present invention includes a fluorine-based copolymer A, a fluorine-based copolymer B, an organic solvent selected from an ester solvent and an aromatic solvent, and a dye selected from a fluorescent dye and a coloring dye , It is a coating agent in which the amount of the solvent is 25% by mass or more based on the total mass of components other than the dye.

(Fluoropolymer A)
Fluorine-based copolymer A contains 60% by mass or more and 99% by mass or less of a fluorine-containing monomer represented by the following general formula (1), and 1 mass of (meth) acrylic acid ester represented by the following general formula (2). % To 40% by mass.

（式中、Ｒ_１は水素又はメチル基であり、ｍは０〜４の整数、ｎは１〜１０の整数を示す。）

(In the formula, R ₁ is hydrogen or a methyl group, m is an integer of 0 to 4, and n is an integer of 1 to 10.)

（式中、Ｒ_１は水素又はメチル基であり、Ｒ_２は炭素数１〜４の直鎖アルキル基または分岐アルキル基を示す。）

(In the formula, R ₁ represents hydrogen or a methyl group, and R ₂ represents a linear alkyl group or branched alkyl group having 1 to 4 carbon atoms.)

  As the fluorine-containing monomer represented by the general formula (1) (also simply referred to as “fluorine-containing monomer”), a methacrylate having a C 1-10 perfluoroalkyl group or a C 1-10 perfluoroalkyl is used. Examples thereof include acrylate having a group. In the following description, “(meth) acrylate” means a methacrylic acid ester (methacrylate) and an acrylic acid ester (acrylate) collectively represented.

  Examples of the (meth) acrylate having a perfluoroalkyl group include perfluorodecyl (meth) acrylate, perfluorodecylethyl (meth) acrylate, perfluorodecylbutyl (meth) acrylate, perfluorononylmethyl (meth) acrylate, and perfluoro Nonylpropyl (meth) acrylate, perfluorooctyl (meth) acrylate, perfluorooctylethyl (meth) acrylate, perfluorooctylbutyl (meth) acrylate, perfluoroheptylmethyl (meth) acrylate, perfluoroheptylpropyl (meth) acrylate , Perfluorohexyl (meth) acrylate, perfluorohexylethyl (meth) acrylate, perfluorohexylbutyl (meth) acrylate, perf Oropenthylmethyl (meth) acrylate, perfluoropentylpropyl (meth) acrylate, perfluorobutyl (meth) acrylate, perfluorobutylethyl (meth) acrylate, perfluorobutylbutyl (meth) acrylate, perfluoropropylmethyl (meth) Acrylate, perfluoropropylpropyl (meth) acrylate, perfluoroethyl (meth) acrylate, perfluoroethylethyl (meth) acrylate, perfluoroethylbutyl (meth) acrylate, perfluoromethylmethyl (meth) acrylate, perfluoromethylpropyl (Meth) acrylate etc. are mentioned, These can be used 1 type or in combination of 2 or more types.

  Of the fluorine-containing monomers, in view of environmental problems, (meth) acrylates having a perfluoroalkyl group having 6 or less carbon atoms are preferred. Specifically, perfluorohexylethyl (meth) acrylate and perfluorobutylethyl (Meth) acrylate is preferred.

Examples of the (meth) acrylic acid ester (also referred to as “short chain alkyl monomer”) represented by the general formula (2) include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) ) Acrylate, n-butyl (meth) acrylate, sec butyl (meth) acrylate, isobutyl (meth) acrylate, tert butyl (meth) acrylate and the like (C) -C4 alkyl group-containing (meth) acrylate.
As the (meth) acrylic acid ester represented by the general formula (2), when a compound having a small number of carbon atoms is used, the coating film made of the fluorine-based copolymer B component which becomes difficult to be compatible with the dirt component and becomes a base. It becomes easy to move to the vicinity of the surface (it becomes easy to bleed out) and oil repellency is improved. Conversely, if the number of carbons exceeds 5, it becomes easy to be compatible with dirt components such as oil, and if it becomes a factor that attracts dirt or is in contact with dirt components, heat it over time or As a result, the soil component may flow and the oil repellency may be reduced.

  As a monomer for producing the fluorinated copolymer A, in addition to the fluorine-containing monomer and the short-chain alkyl monomer, for example, a functional group monomer such as methacrylic acid or acrylic acid can be used.

  As the fluorine-based copolymer A, those having a weight average molecular weight (Mw) of 30,000 or more and 100,000 or less are preferable in that a fluorine-based copolymer particularly excellent in oil repellency is obtained, and the Mw is 30. Particularly preferred are those from 50,000 to 50,000. Further, as the fluorine-based copolymer A, those having a number average molecular weight (Mn) of 20,000 or more and 100,000 or less are preferable in that a fluorine-based copolymer particularly excellent in oil repellency can be obtained. Is particularly preferably from 30,000 to 40,000.

  Next, a method for producing the fluorinated copolymer A will be described. Polymerization is performed by using a fluorine-containing monomer, a short-chain alkyl monomer, and a monomer such as a functional group monomer, if necessary, dissolved or suspended in a polymerization solvent.

  When producing the fluorinated copolymer A, the fluorine-containing monomer is used in a proportion of 60% by mass to 99% by mass and the short-chain alkyl monomer in a proportion of 1% by mass to 40% by mass with respect to the total mass of the monomer. . If the short-chain alkyl monomer is less than 1% by mass, a uniform coating film cannot be formed, and if it exceeds 40% by mass, it is difficult to move (bleed out) to the surface of the coating film. Further, since the fluorine component is reduced, the oil repellency is lowered.

  When producing the fluorinated copolymer A, as a polymerization initiator, for example, an organic peroxide polymerization initiator such as benzoyl peroxide, 2,2′-azobisisobutyronitrile (hereinafter referred to as AIBN). ), Azo compounds such as 2,2′-azobis (isobutyric acid) dimethyl, and the like can be used.

  The polymerization solvent used in preparing the fluorinated copolymer A may be any solvent that can dissolve or suspend a fluorine-containing monomer or a short-chain alkyl monomer, such as butyl acetate, toluene, xylene, n-heptane, An organic solvent such as cyclohexane, tetrahydrofuran, n-hexane, and isohexane, and a fluorine solvent such as 1,3-bistrifluoromethylbenzene, hydrofluorocarbon (HFC), hydrofluoroether (HFE), alone, or two or more kinds Can be used in combination.

(Fluoropolymer B)
Fluorine-based copolymer B has a fluorine-containing monomer (fluorine-containing monomer) represented by general formula (1) of 20% by mass to 50% by mass and (meth) acrylic represented by the following general formula (3). A (meth) acrylic acid ester monomer selected from acid esters is polymerized in an amount of 50% by mass to 80% by mass.

（式中、Ｒ_１は水素又はメチル基であり、Ｒ_３は炭素および水素からなる環状部分を有する官能基を示す。）
フッ素含有モノマーとしては、フッ素系共重合体Ａの材料として説明したモノマーと同様のものを用いることができる。

(In the formula, R ₁ represents hydrogen or a methyl group, and R ₃ represents a functional group having a cyclic portion composed of carbon and hydrogen.)
As a fluorine-containing monomer, the thing similar to the monomer demonstrated as a material of the fluorine-type copolymer A can be used.

  Examples of the (meth) acrylic acid ester (also referred to as “cyclic monomer”) represented by the general formula (3) include styrene (meth) acrylate, benzyl (meth) acrylate, cyclohexyl (meth) acrylate, and cycloheptyl (meth). Acrylate, isobornyl (meth) acrylate, 1-adamantyl (meth) acrylate and the like. These can be used alone or in combination of two or more. Of these cyclic monomers, benzyl (meth) acrylate, isobornyl (meth) acrylate, adamantyl (meth) acrylate, and the like are preferable.

  Since the fluorocopolymer B obtained by using a cyclic monomer is hardly compatible with a soil component such as oil, it has an effect of expelling the soil component (especially the oil component). Of the above, the fluorocopolymer B obtained by using adamantyl (meth) acrylate is preferable in that a coating film having excellent oil repellency can be obtained even at high temperatures.

  As the fluorine-based copolymer B, those having a weight average molecular weight (Mw) of 40,000 or more and 400,000 or less are preferable in that a fluorine-based copolymer particularly excellent in oil repellency can be obtained. Particularly preferred is 50,000 to 300,000. Further, as the fluorine-based copolymer B, those having a number average molecular weight (Mn) of 20,000 or more and 80,000 or less are preferable in that a fluorine-based copolymer particularly excellent in oil repellency can be obtained. Of 23,000 to 70,000 is particularly preferable.

  Next, the manufacturing method of the fluorine-type copolymer B is demonstrated. Polymerization is carried out by dissolving or suspending these in a polymerization solvent using monomers such as a cyclic monomer, a fluorine-based monomer, and, if necessary, a functional group monomer.

  When preparing the fluorinated copolymer B, the fluorine-containing monomer is used in a proportion of 20% by mass to 50% by mass and the cyclic monomer is used in a proportion of 50% by mass to 80% by mass with respect to the total mass of the monomer. When the amount of the fluorine-containing monomer is less than 20% by mass, the dirt component once retreated overflows and flows between the fluorinated copolymer A and the fluorinated copolymer B. If the amount of the fluorine-containing monomer exceeds 50% by mass, it will be repelled by the dirt component and a uniform base cannot be formed.

  As a polymerization initiator used when producing the fluorinated copolymer B, the same polymerization initiator as that used when producing the fluorinated copolymer A can be used. Moreover, as a polymerization solvent used when manufacturing the fluorine-type copolymer B, the thing similar to what is used when producing the fluorine-type copolymer A can be used.

(Organic solvent)
The fluorinated copolymer A and the fluorinated copolymer B can be used as a coating agent by dissolving in a solvent or dispersing in a solvent. In the present invention, an organic solvent or a mixture of an organic solvent and a fluorine solvent is used as a solvent for dissolving or dispersing the fluorine copolymer A and the fluorine copolymer B.

  As the organic solvent, a solvent selected from ester solvents and aromatic solvents is used. Examples of the ester solvent include ethyl acetate and butyl acetate. Aromatic solvents include toluene and xylene. Along with these, a ketone solvent such as acetone may be used. An organic solvent can be used individually or in mixture of 2 or more types.

  The fluorinated solvent used by mixing with an organic solvent is not particularly limited. For example, perfluorocarbon (PFC), hydrofluorocarbon (HFC), hydrochlorofluorocarbon (HCFC), hydrofluoroether (HFE), perfluoropolyester. Ether (PFPE), hydrofluoropolyether (HFPE), 1,3-bistrifluoromethylbenzene and the like can be used. These fluorinated solvents can be used alone or in admixture of two or more.

As the organic solvent, ester solvents, hydrocarbon solvents, and aromatic solvents are preferable, and butyl acetate, toluene, n-heptane, and the like are particularly preferable. Moreover, it is also preferable to use the mixture of an organic solvent and a fluorine-type solvent, and the thing containing butyl acetate is especially preferable.
When a material containing butyl acetate is used, the solubility of various fluorescent dyes and colored dyes is high, and the fluorine-based copolymer A and the fluorine-based copolymer A and the fluorine-based copolymer B are also excellent in solubility. This is because the solubility of the fluorinated copolymer B is excellent.

  The fluorinated copolymer A and the fluorinated copolymer B are such that the solid content concentration of the mixture of the fluorinated copolymer A and the fluorinated copolymer B in the coating agent is 0.1 to 10% by mass. Dissolved in solvent.

  In the mixture of the fluorocopolymer A and the fluorocopolymer B, the mixing ratio of each fluorocopolymer is 5% by mass or more and 30% by mass of the fluorocopolymer A with respect to the total mass of the mixture. Hereinafter, it is preferable that the fluorine-based copolymer B be 70% by mass to 95% by mass. This is because when coating is performed using a coating agent containing a mixture mixed at such a ratio, a coating film having excellent oil repellency after being placed in a high temperature state can be formed. If the amount of the fluorinated copolymer A is less than 5% by mass, the oil repellency may be deteriorated, and if the amount of the fluorinated copolymer A exceeds 30% by mass, it is repelled by the dirt component to form a uniform base. You may not be able to.

The amount of the solvent for dissolving or dispersing the fluorinated copolymer A and the fluorinated copolymer B is 10 to 99.9% by mass in the coating agent. In the present invention, the amount of the organic solvent is 25% by mass or more based on the total mass of components other than the dye. By setting the amount of the organic solvent to 25% by mass or more based on the mass of the components other than the dye , the fluorescent dye or the colored dye can be dissolved in an amount capable of imparting sufficient visibility to the coating film even under a low temperature condition. Can do it.

(dye)
The coating agent of the present invention contains a dye selected from a fluorescent dye and a colored dye in order to impart visibility to the coating film. As the dye, a known fluorescent dye or colored dye can be used. Specific examples of fluorescent dyes include coumarin UV color formers and oxazole UV color formers, and examples of colored dyes include chromium compounds, anthracene compounds, and azo compounds. These can be used alone or in combination of two or more.

  The dye may be added in an amount that can provide visibility to the coating film formed by coating the coating agent, and can be appropriately selected in consideration of the color and material of the substrate on which the coating agent is used. It is. The addition amount of the dye is preferably 0.1 parts by mass or less with respect to 100 parts by mass of the coating agent. If the amount of the dye added is too large, the coating film characteristics may deteriorate.

  In order to improve the practicality, various additives such as an antioxidant, an ultraviolet stabilizer, a filler, a silicone oil, a paraffinic solvent, and a plasticizer can be added to the coating agent of the present invention.

(Application of coating agent)
The coating agent of the present invention can be used for a wide range of applications, such as an oil barrier agent for preventing the diffusion of lubricating oil used for micro motor bearings, an oil barrier agent for preventing the diffusion of lubricating oil used for fluid bearings for HDD motors, Use for moisture-proof coatings to improve the water repellency by orienting fluorine on the surface, chemical-resistant protective coatings that protect the substrate from salt water, electrolytes, corrosive gases, etc., and leakage of ink such as sign pens and ballpoint pens Anti-leakage agent, anti-fouling agent for connectors / electronic parts, insulation resin creep-up preventive agent, MF capacitor lead seal resin adhesion preventive agent, fiber and other water / oil repellent agent, waterproof spray stock solution Can be used.

(Coating method)
As a method for forming a coating film using the coating agent of the present invention, a known method such as a dipping method, a brush coating method, a spray method, or a roll coating method can be employed. It can be appropriately selected in consideration of the form and the like. The coating agent of the present invention can be applied to a base material from which dirt components and the like have been washed and removed in advance before the coating treatment, but to a base material that has not been subjected to washing and removal treatment of dirt components and the like before the coating treatment. It can also be applied. With the coating agent of the present invention, when the base material is coated without performing cleaning and removal of dirt components and the like, it is possible to impart sufficient oil repellency to the base material while omitting the cleaning process. There is an advantage of being excellent.

<Example>
Hereinafter, the present invention will be further described by examples.
(1) Production of Fluoropolymer Fluoropolymer A was produced by Polymerization Example A1 and Polymerization Example A2, and Fluoropolymer B was produced by Polymerization Example B1 and Polymerization Example B2. Table 1 shows the monomers and their amounts used in preparing each fluoropolymer, and the molecular weight (Mw, Mn) of each fluoropolymer.

(Polymerization Example A1)
In a 500 ml round bottom flask, 69 g of perfluorohexylethyl methacrylate, 30 g of methyl methacrylate and 1 g of methacrylic acid were added, and then 70 g of butyl acetate was weighed. Thereafter, 0.2 g of 2,2′-azobisisobutyronitrile (AIBN) was added as a polymerization initiator.
A thermometer, a stirring blade, a cooling pipe, and an N ₂ pipe were set, and the contents in the round bottom flask were stirred at a rotation speed of 100 rpm. After replacing the space of the round bottom flask with N ₂ at room temperature for 30 minutes, hot water was added and the heater was set at 80 ° C. to initiate polymerization. N ₂ continued to flow until the end of the polymerization. The reaction was continued for 5 hours and then cooled to room temperature to obtain a viscous liquid product.
The product in the round bottom flask was taken out, 233 g of butyl acetate was added for dilution, and the concentration (mass basis, the same applies hereinafter) was measured by a drying method and found to be 24.0%.
When GPC (gel permeation chromatograph) of the product was measured, Mn was 35,000 and Mw was 60,000 in terms of polymethyl methacrylate (PMMA).

(Polymerization Example A2)
A polymerization reaction was carried out in the same manner as in Polymerization Example A1, except that 98 g of perfluorohexylethyl methacrylate, 2 g of methyl methacrylate, 100 g of n-heptane, and 0.5 g of AIBN were added to the round bottom flask. As a result, a product containing a syrup-like precipitate was obtained.
When GPC of the product was measured, Mn was 28,000 and Mw was 50,000 in terms of PMMA.

(Polymerization example B1)
Polymerization reaction was carried out in the same manner as in Polymerization Example A1, except that 39 g of perfluorohexylethyl methacrylate, 60 g of isobornyl methacrylate, and 1 g of methacrylic acid were placed in a 500 ml round bottom flask, and then 70 g of butyl acetate was weighed. And a viscous liquid product was obtained.
The product in the round bottom flask was taken out and diluted by adding 233 g of butyl acetate. The concentration was measured by a drying method and found to be 24.5%.
When GPC of the product was measured, Mn was 50,000 and Mw was 300,000 in terms of PMMA.

(Polymerization Example B2)
A polymerization reaction was carried out in the same manner as in Polymerization Example A1, except that 39 g of perfluorohexylethyl methacrylate, 60 g of 1-adamantyl methacrylate and 1 g of methacrylic acid were placed in a 500 ml round bottom flask, and then 70 g of butyl acetate was weighed. A viscous liquid product was obtained.
The product in the round bottom flask was taken out and diluted by adding 233 g of butyl acetate, and the concentration was measured by a drying method to be 24.9%.
When GPC of the product was measured, Mn was 80,000 and Mw was 800,000 in terms of PMMA.

(2) Preparation of coating agent The coating agent was prepared by the following method, and the composition of the coating agent was shown in Tables 3 and 4 together with the results of Test Examples 2 to 3 described later.
Example 1
18.4 g of the 24.5% solution of the product prepared in Polymerization Example B1, 2.1 g of the 24.0% solution of the product prepared in Polymerization Example A1, 29.5 g of butyl acetate, 3FE HFE-7200 Was coated with 0.01 g of a coumarin-based fluorescent agent and sufficiently stirred to obtain a coating agent having a solid content concentration of 5% by mass.
(Comparative Example 1)
5 g of the product produced in Polymerization Example A2, 95 g of 3M HFE-7200, and 0.01 g of a coumarin fluorescent agent were weighed and sufficiently stirred to obtain a coating agent having a solid content concentration of 5 mass%.

(Example 2)
18.4 g of the 24.5% solution of the product prepared in Polymerization Example B1, 2.1 g of the 24.0% solution of the product prepared in Polymerization Example A1, 29.5 g of butyl acetate, 50 g of AE3000 manufactured by Asahi Glass Co., Ltd. Then, 5 g of a 1% by mass solution of oxazole-based fluorescent color former (solvent 1,3-bistrifluoromethylbenzene) was weighed and sufficiently stirred to obtain a coating agent having a solid content concentration of 5% by mass.
(Comparative Example 2)
Weigh 5 g of the product prepared in Polymerization Example A2, 90 g of 3M HFE-7200, and 5 g of 1% by weight oxazole-based fluorescent color former (solvent 1,3-bistrifluoromethylbenzene) and stir well. A coating agent having a solid content concentration of 5% by mass was obtained.

(Example 3)
18.4 g of the 24.5% solution of the product prepared in Polymerization Example B1, 2.1 g of the 24.0% solution of the product prepared in Polymerization Example A1, 29.5 g of butyl acetate, HFE-7100 manufactured by 3M And 0.01 g of black dye (chromium compound) were weighed and sufficiently stirred to obtain a coating agent having a solid content concentration of 5% by mass.
Example 4
18.4 g of the 24.5% solution of the product prepared in Polymerization Example B1, 2.1 g of the 24.0% solution of the product prepared in Polymerization Example A1, 29.5 g of butyl acetate, HFE-7100 manufactured by 3M And a black dye (chromium compound) 0.05 g were weighed and sufficiently stirred to obtain a coating agent having a solid content concentration of 5% by mass.

(Comparative Example 3)
5 g of the product prepared in Polymerization Example A2, 95 g of butyl acetate and 0.01 g of black dye (chromium compound) were weighed and stirred, but the product (fluorine polymer) did not dissolve in butyl acetate.
(Comparative Example 4)
5 g of the product prepared in Polymerization Example A2, 95 g of 3M HFE-7200, and 0.01 g of black dye (chromium compound) were weighed and sufficiently stirred to obtain a coating agent having a solid content concentration of 5 mass%. It was.
(Comparative Example 5)
5 g of the product prepared in Polymerization Example A2, 95 g of AE3000 manufactured by Asahi Glass Co., Ltd. and 0.01 g of black dye (chromium compound) were weighed and sufficiently stirred to obtain a coating agent having a solid content concentration of 5 mass%.
(Comparative Example 6)
5 g of the product prepared in Polymerization Example A2, 95 g of 1,3-bistrifluoromethylbenzene and 0.01 g of black dye (chromium compound) were weighed and sufficiently stirred to obtain a coating agent having a solid content concentration of 5% by mass. Got.

(Example 5)
18.4 g of the 24.5% solution of the product prepared in Polymerization Example B1, 2.1 g of the 24.0% solution of the product prepared in Polymerization Example A1, 80.0 g of toluene, blue dye (anthracene compound) Was weighed and sufficiently stirred to obtain a coating agent having a solid content concentration of 5% by mass.
(Example 6)
18.4 g of the 24.5% solution of the product prepared in Polymerization Example B1, 2.1 g of the 24.0% solution of the product prepared in Polymerization Example A1, 80.0 g of toluene, blue dye (anthracene compound) Was weighed and sufficiently stirred to obtain a coating agent having a solid content concentration of 5% by mass.
(Example 7)
18.4 g of the 24.5% solution of the product prepared in Polymerization Example B1, 2.1 g of the 24.0% solution of the product prepared in Polymerization Example A1, 80.0 g of toluene, blue dye (anthracene compound) Was weighed and sufficiently stirred to obtain a coating agent having a solid content concentration of 5% by mass.

(Comparative Example 7)
18.4 g of the 24.5% solution of the product prepared in Polymerization Example B1, 2.1 g of the 24.0% solution of the product prepared in Polymerization Example A1, 80 g of AE3000 manufactured by Asahi Glass Co., Ltd., blue dye (anthracene series) Compound (0.1 g) was weighed and stirred, but the product (fluorine polymer) was not dissolved in the solvent.
(Example 8)
18.4 g of the 24.5% solution of the product prepared in Polymerization Example B1, 2.1 g of the 24.0% solution of the product prepared in Polymerization Example A1, 10 g of butyl acetate, 70 g of AE3000 manufactured by Asahi Glass Co., Ltd. 0.1 g of a blue dye (anthracene compound) was weighed and sufficiently stirred to obtain a coating agent having a solid content concentration of 5% by mass.
Example 9
18.4 g of the 24.5% solution of the product prepared in Polymerization Example B1, 2.1 g of the 24.0% solution of the product prepared in Polymerization Example A1, 20 g of butyl acetate, 60 g of AE3000 manufactured by Asahi Glass Co., Ltd. 0.1 g of a blue dye (anthracene compound) was weighed and sufficiently stirred to obtain a coating agent having a solid content concentration of 5% by mass.

(Comparative Example 8)
5 g of the product prepared in Polymerization Example A2, 95 g of 3M HFE-7200, and 0.01 g of a blue dye (anthracene compound) were weighed and sufficiently stirred to obtain a coating agent having a solid content concentration of 5% by mass. It was.
(Comparative Example 9)
5 g of the product prepared in Polymerization Example A2, 95 g of AE3000 manufactured by Asahi Glass Co., Ltd., and 0.01 g of blue dye (anthracene compound) were weighed and sufficiently stirred to obtain a coating agent having a solid content concentration of 5 mass%.

(Example 10)
18.4 g of the 24.5% solution of the product prepared in Polymerization Example B1, 2.1 g of the 24.0% solution of the product prepared in Polymerization Example A1, 29.5 g of butyl acetate, AE3000 manufactured by Asahi Glass Co., Ltd. 50 g of yellow dye (azo compound) 0.05 g was weighed and sufficiently stirred to obtain a coating agent having a solid content concentration of 5% by mass.
(Example 11)
18.4 g of the 24.5% solution of the product prepared in Polymerization Example B1, 2.1 g of the 24.0% solution of the product prepared in Polymerization Example A1, 29.5 g of butyl acetate, AE3000 manufactured by Asahi Glass Co., Ltd. 50 g of yellow dye (azo compound) 0.1 g was weighed and sufficiently stirred to obtain a coating agent having a solid content concentration of 5% by mass.

(Comparative Example 10)
5 g of the product prepared in Polymerization Example A2, 95 g of 3M HFE-7200, and 0.01 g of yellow dye (azo compound) are weighed and sufficiently stirred to obtain a coating agent having a solid content concentration of 5 mass%. It was.
(Comparative Example 11)
5 g of the product produced in Polymerization Example A2, 95 g of AE3000 manufactured by Asahi Glass Co., Ltd., and 0.01 g of yellow dye (azo compound) were weighed and sufficiently stirred to obtain a coating agent having a solid content concentration of 5 mass%.
(Comparative Example 12)
5 g of the product prepared in Polymerization Example A2, 95 g of 1,3-bistrifluoromethylbenzene and 0.01 g of yellow dye (azo compound) were weighed and sufficiently stirred to form a coating agent having a solid content concentration of 5% by mass. Got.

(Example 12)
18.4 g of the 24.5% solution of the product prepared in Polymerization Example B1, 2.1 g of the 24.0% solution of the product prepared in Polymerization Example A1, 29.5 g of butyl acetate, AE3000 manufactured by Asahi Glass Co., Ltd. 50 g, 0.05 g of a blue dye (anthracene compound), 1% by mass solution of oxaazole-based fluorescent color former (5 g of solvent 1,3-bistrifluoromethylbenzene) are weighed and thoroughly stirred to obtain a solid content concentration of 5 mass. % Coating agent was obtained.

(3) Evaluation test 1 (oil repellency)
A 20 mm × 20 mm SUS430 plate was washed with n-hexane and isopentyl alcohol (IPA) and sufficiently dried, and then 20 μl of press oil (general-purpose product) was applied to the surface to obtain a test piece S.
A test piece was prepared by applying 200 μl of each coating agent of Examples 1 to 12 to the press oil application surface of the test piece S.
(Measurement of contact angle)
The test pieces prepared by the above method were subjected to the following contact angle measurement using an automatic contact angle DM500 manufactured by Kyowa Interface Science Co., Ltd., and the results are shown in Table 2. Those whose oil repellency was not possible and whose contact angle was not measurable were indicated as “ND” in the table. 1) Contact angle (initial): The static contact angle of the test piece was measured.
2) Contact angle (heat and oil repellency 1: “heat resistance 1” in the table)
Each test piece was stored in a thermostatic bath heated to 80 ° C. with the impregnated oil on it, taken out after 10 minutes, and the static contact angle was measured.
3) Contact angle (heat and oil repellency 2: “heat resistance 2” in the table)
Each test piece was stored in a thermostatic bath heated to 80 ° C. with the impregnated oil on it, taken out after 24 hours, and the static contact angle was measured.
4) Contact angle (heat and oil repellency 3: “heat resistance 3” in the table)
Each test piece was stored in a thermostatic bath heated to 120 ° C. with the impregnated oil on it, taken out after 10 minutes, and the change in static contact angle was measured.

(Results and discussion)
As shown in Table 2, when coating is performed using the coating agents of Examples 1 to 12 in which a mixture obtained by mixing fluorinated copolymer A and fluorinated copolymer B is dissolved in a solvent, the substrate is coated before coating. It was found that oil repellency can be imparted to the surface of the base material without washing and removing the press oil present on the surface.
From the above, when the base material is coated with the coating agent of the present invention, the surface of the base material has sufficient oil repellency even when press oil is present on the surface of the base material (without the base material being washed). It turns out that it can be granted.
In particular, it was found that the coating agent of Example 12 containing the fluorinated copolymer B obtained using adamantyl (meth) acrylate can exhibit excellent oil repellency even at 120 ° C.

(4) Evaluation test 2 (solubility)
Using the coating agents of Examples 1 to 12 and Comparative Examples 1 to 12, solubility was evaluated by the following method.
1) Evaluation of solubility after storage at room temperature After the coating agents of Examples 1 to 12 and Comparative Examples 1 to 12 were stored at room temperature for 24 hours, the coating agent was filtered with a filter paper (Whatman No. 4), and The presence or absence was confirmed visually.
2) Evaluation of solubility after storage at low temperature (−10 ° C.) After storing for 72 hours in a freezer in which the coating agents of Examples 1 to 12 and Comparative Examples 1 to 12 were set to −10 ° C., the coating agent was filtered with paper (Whatman No. 4) and the presence or absence of a filtration residue was confirmed.
The solubility was evaluated according to the following criteria, and the results are shown in Tables 3 and 4. The evaluation criteria are as follows.
○: No filtration residue ×: Filtration residue

(5) Evaluation test 3 (visibility)
(Confirmation of fluorescence development by fluorescent agent)
1) Observation of coating film after drying at room temperature Examples 1-2, 12 and Comparative Examples 1-2 Each coating agent was put in a container, and a glass plate of 76 mm × 26 mm × 0.5 mm (base) in each coating agent. Each material was dipped, and then the substrate was pulled up from the coating agent and dried at room temperature (once dip coating). Thereby, a coating film having a thickness of 1 μm to 3 μm was formed on the surface of each substrate.
The coating film forming portion of each substrate was irradiated with black light (wavelength 365 nm) and the color of the coating film was visually observed, and the results are shown in Table 3.
The case where color development was confirmed was marked with ◯, and the case where color development was not confirmed was marked with X.

2) Observation of coating film after heat treatment (150 ° C., 30 minutes)
The coating agents of Examples 1 and 2, Example 12 and Comparative Examples 1 and 2 are put in containers, respectively, and a glass plate (base material) of 76 mm × 26 mm × 0.5 mm is dipped in each coating agent, respectively, The substrate was lifted from the coating agent and dried at room temperature (once dip coating). Thereby, a coating film having a thickness of 1 μm to 3 μm was formed on the surface of each substrate.
Next, the glass plate on which the coating film was formed was dried at 150 ° C. for 30 minutes, and the coating film formation portion was irradiated with black light (wavelength 365 nm), and the color of the coating film was visually observed. It is shown in Table 4.
The case where color development was confirmed was marked with ◯, and the case where color development was not confirmed was marked with X.

(Confirmation of coloring)
Each of the coating agents of Examples 3 to 12 and Comparative Examples 3 to 12 is placed in a container, and a glass plate (base material) of 76 mm × 26 mm × 0.5 mm is immersed in each coating agent, and then the base material is coated. It was pulled up from the agent and dried at room temperature (once dip coating). Thereby, a coating film having a thickness of 1 μm to 3 μm was formed on the surface of each substrate.
For the base material on which the coating film is formed, the total light transmittance is measured using a turbidimeter (NDH5000) manufactured by Nippon Denshoku Co., Ltd., the degree of coloring is judged according to the following criteria, and the results are shown in Table 3 and The results are shown in Table 4.
The total light transmittance of the blank (base material without a coating agent applied) is 93%, and the lower the measured value, the better the colorability. If the total light transmittance is less than 90% (if the evaluation result is Δ, ◯, ◎), coloring can be confirmed visually.
Evaluation criteria x: Total light transmittance of 90% or more Δ: Total light transmittance of 80% or more and less than 90% ○: Total light transmittance of 70% or more and less than 80% ◎: Total light transmittance of less than 70%

(Results and discussion)
(1) As shown in Table 3 and Table 4, in the coating agents of Examples 1 to 12, the solubility of the dye was good at both room temperature and low temperature.
The coating films prepared using the coating agents of Examples 1, 2, and 12 were visually recognized as being colored by fluorescence at room temperature. Moreover, the coating film produced using the coating agent of Examples 3-12 was also visually recognizable. From these results, it was found that when the coating agent of the present invention was used, the solubility of the dye was good, and the visibility of the formed coating film was also high.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.
(1) In the above-mentioned examples, perfluorohexylethyl methacrylate was used as the fluorine-containing monomer represented by the general formula (1), but perfluorooctylethyl (meth) acrylate, perfluoroheptylethyl ( Meth) acrylate, perfluoropentylethyl (meth) acrylate and perfluorobutylethyl (meth) acrylate may be used.
(2) In the above examples, methyl methacrylate was used as the (meth) acrylic acid ester represented by the general formula (2), but methyl acrylate, ethyl (meth) acrylate, propyl (meth) acrylate Butyl (meth) acrylate may be used.
(3) In the above examples, examples in which isobornyl methacrylate or 1-adamantyl methacrylate is used as the (meth) acrylic acid ester represented by the general formula (3) are shown. However, benzyl (meth) acrylate and isobornyl are used. Acrylate, styrene (meth) acrylate, cyclohexyl (meth) acrylate, cycloheptyl (meth) acrylate, or the like may be used.

Claims (4)

60% to 99% by mass of a fluorine-containing monomer represented by the following general formula (1) and 1% to 40% by mass of a (meth) acrylate represented by the following general formula (2) are polymerized. A fluorine-based copolymer A,
The fluorine-containing monomer represented by the following general formula (1) is 20% by mass to 50% by mass and the (meth) acrylic acid ester represented by the following general formula (3) is 50% by mass to 80% by mass; A fluorine-based copolymer B obtained by polymerizing
An organic solvent selected from ester solvents and aromatic solvents, and a dye selected from fluorescent dyes and colored dyes ,
The coating agent whose quantity of the said organic solvent is 25 mass% or more with respect to the total mass of components other than the said dye.

(In the formula, R1 is hydrogen or a methyl group, m is an integer of 0 to 4, and n is an integer of 1 to 10.)

(In the formula, R1 represents hydrogen or a methyl group, and R2 represents a linear alkyl group or branched alkyl group having 1 to 4 carbon atoms.)

(In the formula, R1 represents hydrogen or a methyl group, and R3 represents a functional group having a cyclic portion composed of carbon and hydrogen.)   2. The coating agent according to claim 1, wherein the fluorine-containing copolymer A is contained in a proportion of 5% by mass or more and 30% by mass or less with respect to the total mass of the fluorine-based copolymer A and the fluorine-based copolymer B. .   The coating agent according to claim 1, wherein the organic solvent contains butyl acetate.   A method for forming a coating film using the coating agent according to any one of claims 1 to 3.