JP2011183347A - Method for forming film, film and coating liquid - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for forming a film capable of broadly controlling water repellency of the surface of an object, also to provide a film, and further to provide a coating liquid. <P>SOLUTION: The method for forming the film includes a process for applying the coating liquid containing a melamine derivative, a resin having a functional group capable of reacting with the melamine derivative, a material having a hydrophobic group, and a solvent, onto the surface of the object and a process for reacting the melamine derivative with the resin contained in the coating liquid coated on the surface of the object. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a film forming method, a film, and a coating solution.

  Conventionally, as a method for controlling the water repellency of the surface of an object, a method of forming a film with a small contact angle with water, a method of forming a film with a large contact angle with water, a method of applying a hydrophobic oil repellent, etc. are known. ing. In addition, a method of laminating a hydrophobic self-assembled film on a coating film or fixing it by physical adsorption or chemical adsorption is also known.

Patent Document 1 discloses a silicon compound (A) represented by Si (OR) ₄ , a silicon compound (B) represented by CF ₃ (CF ₂ ) _n CH ₂ CH ₂ Si (OR ¹ ) ₃ , and H _2. A reaction mixture containing a silicon compound (C) represented by NCONH (CH) _m Si (OR ² ) ₃ , an alcohol (D) represented by R ³ CH ₂ OH and oxalic acid (E) in a specific ratio is formed. The reaction mixture is heated at 40 to 180 ° C. in the absence of water to form a polysiloxane solution, and a coating solution containing the solution is applied to the substrate surface. A film is disclosed which is formed in close contact with the surface of the substrate by thermosetting at ˜450 ° C. and exhibits a refractive index of 1.28 to 1.41 and a water contact angle of 90 to 115 degrees.

  However, there is a problem that the water repellency of the surface of the object cannot be controlled widely.

  The present invention has been made in view of the above-described problems of the prior art, and an object thereof is to provide a film forming method, a film, and a coating liquid capable of widely controlling the water repellency of the surface of an object.

  According to the first aspect of the present invention, in the film forming method, a coating liquid containing a melamine derivative, a resin having a functional group capable of reacting with the melamine derivative, a material having a hydrophobic group, and a solvent is applied to the surface of the object. And a step of reacting a resin with a melamine derivative contained in a coating solution applied to the surface of the object.

  According to a second aspect of the present invention, in the film forming method according to the first aspect, the melamine derivative is an alkylated melamine resin.

  According to a third aspect of the present invention, in the film forming method according to the second aspect, the melamine derivative is a methylated melamine resin.

  The invention according to claim 4 is the film forming method according to any one of claims 1 to 3, wherein the resin has an aromatic group substituted with a hydroxyl group, and the hydrophobic group. The material having a functional group capable of reacting with the hydroxyl group has the hydrophobic group when the resin reacts with the melamine derivative contained in the coating liquid applied to the surface of the object. The material and the resin are reacted.

  The invention according to claim 5 is the film forming method according to any one of claims 1 to 3, wherein the resin has an aromatic group substituted with a hydroxyl group, and the hydrophobic group. The material having a characteristic is polyimide.

  The invention according to claim 6 is the film forming method according to any one of claims 1 to 3, wherein the resin is polyimide, and the material having the hydrophobic group is polyamic acid, When the melamine derivative contained in the coating solution applied to the surface of the object is reacted with the resin, the material having the hydrophobic group is reacted with the melamine derivative.

  The invention described in claim 7 is characterized in that the film is formed by using the film forming method according to any one of claims 1 to 6.

  The invention described in claim 8 is characterized in that the coating solution contains a melamine derivative, a resin having a functional group capable of reacting with the melamine derivative, a material having a hydrophobic group, and a solvent.

  ADVANTAGE OF THE INVENTION According to this invention, the formation method of a film | membrane and film | membrane and coating liquid which can control the water repellency of the surface of an object widely can be provided.

  Next, the form for implementing this invention is demonstrated.

  The method for forming a film of the present invention comprises a step of applying a coating liquid containing a melamine derivative, a resin having a functional group capable of reacting with the melamine derivative, a material having a hydrophobic group, and a solvent to the surface of the object, A step of reacting the resin with the melamine derivative contained in the coating solution applied to the surface of the substrate.

  The melamine derivative is not particularly limited, and examples thereof include alkylated melamine resins such as methylated melamine resin, butylated melamine resin, and isobutylated melamine resin; melamine resin; melamine, methylol melamine, etc. Good.

  Although it does not specifically limit as resin which has a functional group which can react with a melamine derivative, Resin which has an aromatic group substituted by hydroxyl groups, such as polyvinylphenol and a phenol resin; It has imide groups, such as a polyimide Resin; Examples thereof include resins having a carboxyl group such as polyamic acid, and two or more of them may be used in combination. When forming an insulating film, polyamic acid or polyimide is preferable.

  The resin having a functional group capable of reacting with the melamine derivative is preferably less hydrophobic than the material having a hydrophobic group. Moreover, it is preferable that the resin having a functional group capable of reacting with a melamine derivative and the material having a hydrophobic group are soluble in the same solvent. Thereby, the material having a hydrophobic group is likely to float on the surface of the film.

  The mass ratio of the melamine derivative to the resin having a functional group capable of reacting with the melamine derivative is usually 0.001 to 3, preferably 0.05 to 1.

  Although it does not specifically limit as a material which has a hydrophobic group, A polyimide, a polyamic acid, etc. are mentioned, You may use 2 or more types together. Among these, a material having a functional group capable of reacting with a hydroxyl group is preferable.

  The hydrophobic group is not particularly limited, and examples thereof include an alkyl group and an alkyl group substituted with a fluoro group.

  Although it does not specifically limit as a material which has a functional group which can react with a hydroxyl group, Silane coupling agents, such as trichlorosilyl compounds, such as n-octadecyl trichlorosilane, Silsesquioxane, etc. are mentioned.

  Although it does not specifically limit as a solvent, Butanol, N-methylpyrrolidone, (gamma) -butyllactone, cyclohexanone, etc. are mentioned, You may use 2 or more types together. When used in electronic device applications, it is preferable to use a solvent having a low boiling point.

  Although it does not specifically limit as an object which apply | coats a coating liquid on the surface, A glass substrate, a polyimide board | substrate, a polyethylene terephthalate board | substrate, a polyether sulfone board | substrate, a polycarbonate board | substrate, a polyethylene naphtholate board | substrate, a stainless steel board | substrate etc. are mentioned. When used in electronic device applications, an alkali-free glass substrate is preferred.

  The method for applying the coating liquid to the surface of the object is not particularly limited, and examples thereof include a spin coating method, a die coater method, a flexographic printing method, a gravure printing method, a screen printing method, and a lithographic printing method.

  The object having the coating liquid applied to the surface is dried, if necessary, and then reacted with a melamine derivative and a resin having a functional group capable of reacting with the melamine derivative.

  A method for drying an object having a coating solution applied to the surface is not particularly limited, and examples thereof include vacuum drying.

  The method for reacting the melamine derivative with a resin having a functional group capable of reacting with the melamine derivative is not particularly limited, and examples thereof include heating and ultraviolet irradiation.

  Hereinafter, a specific configuration of the coating liquid used in the present invention will be described.

  The first embodiment of the coating solution includes a melamine derivative, a resin having an aromatic group substituted with a hydroxyl group, and a material having a functional group and a hydrophobic group capable of reacting with the hydroxyl group. In this case, when the melamine derivative contained in the coating solution applied to the surface of the object is reacted with a resin having an aromatic group substituted with a hydroxyl group, a functional group capable of reacting with the hydroxyl group and a hydrophobic group. A material having a functional group reacts with a resin having an aromatic group substituted with a hydroxyl group. As a result, the water repellency of the film is lowered by increasing the content of the melamine derivative in the coating solution. This is because a resin having an aromatic group substituted with a hydroxyl group reacts with a melamine derivative, so that a resin having an aromatic group substituted with a hydroxyl group can react with the hydroxyl group. And it is thought that it is because the material which has a hydrophobic group becomes difficult to react.

  The second embodiment of the coating solution includes a melamine derivative, a resin having an aromatic group substituted with a hydroxyl group, and a polyimide having a hydrophobic group. In this case, when the melamine derivative contained in the coating solution applied to the surface of the object is reacted with the resin having an aromatic group substituted with a hydroxyl group, the polyimide having a hydrophobic group and the hydroxyl group are substituted. Resin having aromatic group does not react. As a result, the water repellency of the film is improved by increasing the content of the melamine derivative in the coating solution. This is presumably because the resin having an aromatic group substituted with a hydroxyl group reacts with the melamine derivative, so that the polyimide having a hydrophobic group easily floats on the surface of the film.

  3rd embodiment of a coating liquid contains the polyamic acid which has a melamine derivative, a polyimide, and a hydrophobic group. In this case, when the melamine derivative contained in the coating solution applied to the surface of the object is reacted with the polyimide, the polyamic acid having a hydrophobic group and the melamine derivative react. As a result, the water repellency of the film is lowered by increasing the content of the melamine derivative in the coating solution. This is because the polyamic acid having a hydrophobic group reacts with the melamine derivative, so that the polyamic acid having the hydrophobic group or the polyimide derived from the polyamic acid having the hydrophobic group is less likely to float on the surface of the film. Conceivable.

  As described above, the water repellency of the surface of the object can be widely controlled by applying the coating liquid to the surface of the object to form a film.

  The film formation method of the present invention can be applied to the formation of insulating films of electronic devices such as gate insulating films and interlayer insulating films of field effect transistors.

  The film forming method of the present invention is also useful in fields such as printing technology, anti-fogging / antifouling technology, as well as various sensor materials, environmentally responsive materials, and various switching materials.

  Next, the present invention will be specifically described with reference to examples, but the present invention is not limited to the examples.

[Comparative Example 1]
After dissolving 10 g of Marcalinker M (manufactured by Maruzen Petrochemical Co., Ltd.) of poly (p-vinylphenol) having a weight average molecular weight of 22000 in 100 ml of butanol, 0.20 g of n-octadecyltrichlorosilane (manufactured by Shin-Etsu Chemical Co., Ltd.) In addition, the mixture was stirred using a stirrer to obtain a coating solution.

  The obtained coating solution was applied onto a glass substrate by spin coating, and then baked at 200 ° C. in an inert gas atmosphere to obtain a thin film having a thickness of 700 nm.

  When the contact angle of the obtained thin film with ultrapure water was measured by a droplet method using a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd.), it was 110 °.

[Example 1]
After dissolving 10 g of Marcalinker M (manufactured by Maruzen Petrochemical Co., Ltd.) of poly (p-vinylphenol) having a weight average molecular weight of 22000 in 100 ml of butanol, 0.20 g of n-octadecyltrichlorosilane (manufactured by Shin-Etsu Chemical Co., Ltd.) In addition, the mixture was stirred using a stirrer. Next, methylated melamine resin (manufactured by Sigma Aldrich Japan) was added and stirred using a stirrer to obtain a coating solution. The methylated melamine resin was changed in mass ratio with respect to poly (p-vinylphenol) as shown in Table 1.

  The obtained coating solution was applied onto a glass substrate by spin coating, and then baked at 200 ° C. in an inert gas atmosphere to obtain a film having a thickness of 700 nm.

  The contact angle of the obtained membrane with respect to ultrapure water was measured by a droplet method using a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd.). The measurement results are shown in Table 1. In addition, mass ratio means the mass ratio of the methylated melamine resin with respect to poly (p-vinylphenol).

表１から、メチル化メラミン樹脂の添加量を増大させることにより、膜の撥水性が低下することがわかる。これは、ポリ（ｐ−ビニルフェノール）がメチル化メラミン樹脂と反応して架橋することにより、立体障害が発生し、ポリ（ｐ−ビニルフェノール）とｎ−オクタデシルトリクロロシランが反応しにくくなるためであると考えられる。なお、実施例１及び比較例１の膜は、超純水に対する接触角が７０°以下であるポリ（ｐ−ビニルフェノール）膜よりも撥水性が大きい。

From Table 1, it can be seen that the water repellency of the film is lowered by increasing the addition amount of the methylated melamine resin. This is because poly (p-vinylphenol) reacts with the methylated melamine resin and crosslinks to cause steric hindrance, making it difficult for poly (p-vinylphenol) and n-octadecyltrichlorosilane to react. It is believed that there is. In addition, the film | membrane of Example 1 and Comparative Example 1 has a water repellency larger than the poly (p-vinylphenol) film | membrane whose contact angle with respect to an ultrapure water is 70 degrees or less.

  As described above, it can be seen that the water repellency of the poly (p-vinylphenol) film can be controlled by adjusting the addition amounts of n-octadecyltrichlorosilane and methylated melamine resin. Similar effects can be obtained by using alkylated melamine resin such as butylated melamine resin and isobutylated melamine resin, melamine resin and methylol melamine instead of methylated melamine resin.

[Comparative Example 2]
After dissolving 20 g of phenolic resin top PSM-4326 (manufactured by Gunei Chemical Industry Co., Ltd.) in 100 ml of butanol, 0.4 g of n-octadecyltrichlorosilane (manufactured by Shin-Etsu Chemical Co., Ltd.) was added and stirred using a stirrer. A coating solution was obtained.

  The obtained coating solution was applied onto a glass substrate by spin coating, and then baked at 200 ° C. in an inert gas atmosphere to obtain a film having a thickness of 700 nm.

  When the contact angle of the obtained membrane with respect to ultrapure water was measured by a droplet method using a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd.), it was 111 °.

[Example 2]
After 20 g of phenolic resin top PSM-4326 (manufactured by Gunei Chemical Industry Co., Ltd.) was dissolved in 100 ml of butanol, 0.4 g of n-octadecyltrichlorosilane (manufactured by Shin-Etsu Chemical Co., Ltd.) was added and stirred using a stirrer. Next, methylated melamine resin (manufactured by Sigma Aldrich Japan) was added and stirred using a stirrer to obtain a coating solution. In addition, the methylated melamine resin was changed in mass ratio with respect to the phenol resin as shown in Table 2.

  The obtained coating solution was applied onto a glass substrate by spin coating, and then baked at 200 ° C. in an inert gas atmosphere to obtain a film having a thickness of 700 nm.

  The contact angle of the obtained membrane with respect to ultrapure water was measured by a droplet method using a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd.). The measurement results are shown in Table 2. In addition, mass ratio means the mass ratio of methylated melamine resin with respect to phenol resin.

表２から、メチル化メラミン樹脂の添加量を増大させることにより、膜の撥水性が低下することがわかる。これは、フェノール樹脂がメチル化メラミン樹脂と反応して架橋することにより、立体障害が発生し、フェノール樹脂とｎ−オクタデシルトリクロロシランが反応しにくくなるためであると考えられる。なお、実施例２及び比較例２の膜は、超純水に対する接触角が７０°以下であるフェノール樹脂膜よりも撥水性が大きい。

From Table 2, it can be seen that the water repellency of the film is lowered by increasing the addition amount of the methylated melamine resin. This is considered to be because the phenol resin reacts with the methylated melamine resin and crosslinks to cause steric hindrance and the phenol resin and n-octadecyltrichlorosilane hardly react. In addition, the film | membrane of Example 2 and Comparative Example 2 has water repellency larger than the phenol resin film whose contact angle with respect to ultrapure water is 70 degrees or less.

  As described above, it is understood that the water repellency of the phenol resin film can be controlled by adjusting the addition amounts of n-octadecyltrichlorosilane and methylated melamine resin. The same effect can be obtained by using alkylated melamine resin such as butylated melamine resin and isobutylated melamine resin, melamine resin, melamine and methylol melamine instead of methylated melamine resin.

[Comparative Example 3]
After dissolving 10 g of Marcalinker M (Maruzen Petrochemical) of poly (p-vinylphenol) having a weight average molecular weight of 22000 in 100 ml of N-methylpyrrolidone, the chemical formula

で表されるポリイミド（Ａ）０．２５ｇを加え、スターラーを用いて攪拌し、塗布液を得た。

Was added using a stirrer to obtain a coating solution.

  The obtained coating solution was applied onto a glass substrate by spin coating, and then baked at 200 ° C. in an inert gas atmosphere to obtain a film having a thickness of 700 nm.

  When the contact angle of the obtained membrane with respect to ultrapure water was measured by a droplet method using a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd.), it was 80 °.

[Example 3]
After dissolving 10 g of Marcalinker M (Maruzen Petrochemical) of poly (p-vinylphenol) having a weight average molecular weight of 22000 in 100 ml of N-methylpyrrolidone, 0.25 g of polyimide (A) is added and stirred using a stirrer. did. Next, methylated melamine resin (manufactured by Sigma Aldrich Japan) was added and stirred using a stirrer to obtain a coating solution. The methylated melamine resin was changed in mass ratio with respect to poly (p-vinylphenol) as shown in Table 3.

  The obtained coating solution was applied onto a glass substrate by spin coating, and then baked at 200 ° C. in an inert gas atmosphere to obtain a film having a thickness of 700 nm.

  The contact angle of the obtained membrane with respect to ultrapure water was measured by a droplet method using a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd.). Table 3 shows the measurement results. In addition, mass ratio means the mass ratio of the methylated melamine resin with respect to poly (p-vinylphenol).

表３から、メチル化メラミン樹脂の添加量を増大させることにより、膜の撥水性が向上することがわかる。これは、ポリ（ｐ−ビニルフェノール）がメチル化メラミン樹脂と反応して架橋することにより、ポリイミド（Ａ）が膜の表面に浮上しやすくなるためであると考えられる。なお、実施例３及び比較例３の膜は、超純水に対する接触角が７０°以下であるポリ（ｐ−ビニルフェノール）膜よりも撥水性が大きい。

From Table 3, it can be seen that the water repellency of the film is improved by increasing the addition amount of the methylated melamine resin. This is considered to be because the polyimide (A) is likely to float on the surface of the film when poly (p-vinylphenol) reacts with the methylated melamine resin and crosslinks. In addition, the film | membrane of Example 3 and Comparative Example 3 has a water repellency larger than the poly (p-vinylphenol) film | membrane whose contact angle with respect to an ultrapure water is 70 degrees or less.

  As described above, it is understood that the water repellency of the poly (p-vinylphenol) film can be controlled by adjusting the addition amount of the polyimide (A) and the methylated melamine resin. Similar effects can be obtained by using alkylated melamine resin such as butylated melamine resin and isobutylated melamine resin, melamine resin and methylol melamine instead of methylated melamine resin.

[Comparative Example 4]
After 8 g of polyimide CT4112 (manufactured by Kyocera Chemical Co.) was dissolved in 100 ml of N-methylpyrrolidone, 0.26 g of polyimide (A) was added and stirred using a stirrer to obtain a coating solution.

  The obtained coating solution was applied onto a glass substrate by spin coating, and then baked at 200 ° C. in an inert gas atmosphere to obtain a film having a thickness of 700 nm.

  The contact angle of the obtained membrane with respect to ultrapure water was measured by a droplet method using a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd.) and found to be 75 °.

[Example 4]
After 8 g of polyimide CT4112 (manufactured by Kyocera Chemical Co.) was dissolved in 100 ml of N-methylpyrrolidone, 0.26 g of polyimide (A) was added and stirred using a stirrer. Next, methylated melamine resin (manufactured by Sigma Aldrich Japan) was added and stirred using a stirrer to obtain a coating solution. In addition, as for methylated melamine resin, mass ratio with respect to polyimide CT4112 was changed as shown in Table 4.

  The obtained coating solution was applied onto a glass substrate by spin coating, and then baked at 200 ° C. in an inert gas atmosphere to obtain a film having a thickness of 700 nm.

  The contact angle of the obtained membrane with respect to ultrapure water was measured by a droplet method using a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd.). Table 4 shows the measurement results. In addition, mass ratio means the mass ratio of the methylated melamine resin with respect to polyimide CT4112.

表４から、メチル化メラミン樹脂の添加量を増大させることにより、膜の撥水性が向上することがわかる。これは、ポリイミドＣＴ４１１２がメチル化メラミン樹脂と反応して架橋することにより、ポリイミド（Ａ）が膜の表面に浮上しやすくなるためであると考えられる。なお、実施例４及び比較例４の膜は、超純水に対する接触角が７３°以下であるポリイミドＣＴ４１１２の膜よりも撥水性が大きい。

Table 4 shows that the water repellency of the film is improved by increasing the addition amount of the methylated melamine resin. This is considered to be because the polyimide (A) is likely to float on the surface of the film when the polyimide CT4112 reacts with the methylated melamine resin and crosslinks. The films of Example 4 and Comparative Example 4 have a higher water repellency than the polyimide CT4112 film having a contact angle with respect to ultrapure water of 73 ° or less.

  As described above, it is understood that the water repellency of the polyimide CT4112 film can be controlled by adjusting the addition amount of the polyimide (A) and the methylated melamine resin. Similar effects can be obtained by using alkylated melamine resin such as butylated melamine resin and isobutylated melamine resin, melamine resin, and melamine instead of methylated melamine resin.

[Comparative Example 5]
After dissolving 8 g of polyimide CT4112 (manufactured by Kyocera Chemical) in 100 ml of N-methylpyrrolidone, the chemical formula

で表されるポリアミド酸（Ａ）の６質量％Ｎ−メチルピロリドン溶液８ｇを加え、スターラーを用いて攪拌し、塗布液を得た。

8 g of a 6% by mass N-methylpyrrolidone solution of polyamic acid (A) represented by the formula (I) was added and stirred using a stirrer to obtain a coating solution.

  The obtained coating solution was applied onto a glass substrate by spin coating, and then baked at 200 ° C. in an inert gas atmosphere to obtain a film having a thickness of 700 nm.

  When the contact angle of the obtained membrane with respect to ultrapure water was measured by a droplet method using a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd.), it was 93 °.

[Example 5]
After 8 g of polyimide CT4112 (manufactured by Kyocera Chemical Co.) was dissolved in 100 ml of N-methylpyrrolidone, 8 g of a 6 mass% N-methylpyrrolidone solution of polyamic acid (A) was added and stirred using a stirrer. Next, methylated melamine resin (manufactured by Sigma Aldrich Japan) was added and stirred using a stirrer to obtain a coating solution. In addition, as for methylated melamine resin, mass ratio with respect to polyimide CT4112 was changed as shown in Table 5.

  The obtained coating solution was applied onto a glass substrate by spin coating, and then baked at 200 ° C. in an inert gas atmosphere to obtain a film having a thickness of 700 nm.

  The contact angle of the obtained membrane with respect to ultrapure water was measured by a droplet method using a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd.). Table 5 shows the measurement results. In addition, mass ratio means the mass ratio of the methylated melamine resin with respect to polyimide CT4112.

表５から、メチル化メラミン樹脂の添加量を増大させることにより、膜の撥水性が低下することがわかる。これは、ポリアミド酸（Ａ）がメチル化メラミン樹脂と反応して架橋することにより、ポリアミド酸（Ａ）又はポリアミド酸（Ａ）由来のポリイミドが膜の表面に浮上しにくくなるためであると考えられる。なお、実施例５及び比較例５の膜は、超純水に対する接触角が７３°以下であるポリイミドＣＴ４１１２の膜よりも撥水性が大きい。

From Table 5, it can be seen that the water repellency of the film is lowered by increasing the amount of methylated melamine resin added. This is considered to be because the polyamic acid (A) or the polyimide derived from the polyamic acid (A) is less likely to float on the surface of the film when the polyamic acid (A) reacts with the methylated melamine resin and crosslinks. It is done. In addition, the film | membrane of Example 5 and the comparative example 5 has a water repellency larger than the film | membrane of the polyimide CT4112 whose contact angle with respect to an ultrapure water is 73 degrees or less.

  As described above, it can be seen that the water repellency of the polyimide CT4112 film can be controlled by adjusting the addition amounts of the polyamic acid (A) and the methylated melamine resin. Similar effects can be obtained by using alkylated melamine resin such as butylated melamine resin and isobutylated melamine resin, melamine resin, and melamine instead of methylated melamine resin.

WO2005 / 059050

Claims (8)

Applying a coating solution containing a melamine derivative, a resin having a functional group capable of reacting with the melamine derivative, a material having a hydrophobic group, and a solvent to the surface of the object;
A method for forming a film, comprising the step of reacting a resin with a melamine derivative contained in a coating solution applied to the surface of the object.   The method for forming a film according to claim 1, wherein the melamine derivative is an alkylated melamine resin.   The method for forming a film according to claim 2, wherein the melamine derivative is a methylated melamine resin. The resin has an aromatic group substituted with a hydroxyl group;
The material having the hydrophobic group has a functional group capable of reacting with the hydroxyl group,
The material having the hydrophobic group and the resin are reacted when the melamine derivative contained in the coating liquid applied to the surface of the object is reacted with the resin. The method for forming a film according to item. The resin has an aromatic group substituted with a hydroxyl group;
The method for forming a film according to claim 1, wherein the material having a hydrophobic group is polyimide. The resin is polyimide,
The material having the hydrophobic group is polyamic acid,
4. The material according to claim 1, wherein the material having the hydrophobic group is reacted with the melamine derivative when the resin reacts with the melamine derivative contained in the coating liquid applied to the surface of the object. The method for forming a film according to one item.   A film formed by using the film forming method according to claim 1.   A coating liquid comprising a melamine derivative, a resin having a functional group capable of reacting with the melamine derivative, a material having a hydrophobic group, and a solvent.