KR102661829B1 - Fluoropolymer coating composition with excellent chemical resistance and antifouling - Google Patents

Abstract

Fluorine-based polymer; hardener; and a solvent; wherein the fluorine-based polymer contains at least one functional group selected from the group consisting of an acrylate group, a carboxyl group, and a hydroxy group, the curing agent contains an isocyanate group, and the solvent is propylene glycol methyl ether acetate ( A fluorine-based polymer coating composition that is a mixed solvent of propylene glycol methyl ether acetate (PGMEA) and methyl isobutyl ketone (MIBK) is disclosed.

Description

Fluoropolymer coating composition with excellent chemical resistance and antifouling}

It relates to a fluorine-based polymer coating composition with excellent chemical resistance and contamination resistance.

The process gases discharged from the exhaust line by the pump in semiconductor processing equipment are highly toxic, corrosive, highly explosive, and ignitable gases. Among the processes that produce semiconductor devices, there are many processes that emit toxic gases, for example, chemical vapor deposition. (Chemical Vapor Deposition; CVD) process, ion implantation process, etching process, diffusion process, etc. SiH ₄ , SiH ₂ , NO, AsH ₃ , PH ₃ , NH ₃ , N ₂ O, SiH ₂ , Cl _2, etc. of gases are being used.

These gases released through the process contain various types of toxic substances. These toxic gases are not only harmful to the human body, but are also flammable and corrosive, causing accidents such as fires. Additionally, when these toxic gases are released into the atmosphere, they can cause serious health problems. Because it causes environmental pollution, the gas goes through a purification process in a filtration device before it is released into the atmosphere.

In addition, even if contaminants are purified through a wet scrubber installed and used in a conventional semiconductor manufacturing line, the emitted gas still contains low concentrations of harmful gases such as hydrofluoric acid, and the contained harmful gases can penetrate pipes, etc. during the flow process. There is a problem with corrosion.

Fluorine-based polymers exhibit differentiated characteristics that cannot be replaced by other materials in terms of durability, weather resistance, corrosion resistance, lubricity, wear resistance, contamination resistance, antistatic properties, and electromagnetic wave shielding properties, so they are widely used in national fields such as electrical and electronics, automobiles, chemicals, and civil engineering. In industry, it is applied to a variety of products ranging from general-purpose consumer goods to high-tech fields, and is recognized as an important material that contributes to the high functionality and added value of products.

Japanese Patent Publication No. 2013-177535 discloses a fluorine-containing copolymer capable of forming a coating film with excellent self-healing properties against wounds and a coating composition using the same, comprising (a) a polymerization unit based on a fluorine-containing monomer, (b) glass. Polymerization units based on vinyl ethers or vinyl esters (but excluding those having hydroxyl groups and carboxyl groups) that give homopolymers with a transition temperature of 25°C or lower, (c) monomers having hydroxyl groups (but excluding those having carboxyl groups) ), and (d) a polymerization unit based on a monomer having a carboxyl group (however, excluding those having a hydroxyl group), and the polymerization unit (b) is contained in an amount of 8.0 to 40.0 mol relative to the pre-polymerization unit. A solvent-soluble fluorinated copolymer containing % and a coating composition using the same are disclosed.

However, curable compositions using such fluorine-based polymers, for example, lack durability, abrasion resistance, and adhesion even if weather resistance, contamination resistance, etc. are secured, or even if durability, abrasion resistance, and adhesion are secured, weather resistance, corrosion resistance, and contamination resistance are insufficient. There is a problem with the back being lacking.

Accordingly, in the present invention, a fluorine-based coating resin with excellent chemical resistance and water/oil repellency was developed and applied to equipment for the back-end of semiconductor manufacturing, including scrubbers, piping, etc., through coating, thereby preventing corrosion of parts and powder deposition by toxic gases and toxic substances. The purpose is to minimize and thereby improve durability.

The present invention seeks to provide a coating composition that has low surface energy, high acid resistance, and organic solvent stability, while also having high pencil strength.

In order to achieve the above object, in one aspect of the present invention

fluorine-based polymer; hardener; and solvent;

The fluorine-based polymer contains at least one functional group selected from the group consisting of an acrylate group, a carboxyl group, and a hydroxy group,

The curing agent contains an isocyanate group,

A fluorine-based polymer coating composition is provided as the solvent, which is a mixed solvent of propylene glycol methyl ether acetate (PGMEA) and methyl isobutyl ketone (MIBK).

Additionally, in another aspect of the present invention

A fluorine-based polymer containing at least one functional group selected from the group consisting of an acrylate group, a carboxyl group, and a hydroxy group; A curing agent containing an isocyanate group; and a solvent that is a mixed solvent of propylene glycol methyl ether acetate (PGMEA) and methyl isobutyl ketone (MIBK). A method for producing a fluorine-based polymer coating composition comprising a step of mixing is provided. do.

Furthermore, in another aspect of the present invention

A fluorine-based polymer coating film formed by coating the above-described fluorine-based polymer coating composition is provided.

Furthermore, in another aspect of the present invention

A fluorine-based polymer containing at least one functional group selected from the group consisting of an acrylate group, a carboxyl group, and a hydroxy group; A curing agent containing an isocyanate group; and a solvent, which is a mixed solvent of propylene glycol methyl ether acetate (PGMEA) and methyl isobutyl ketone (MIBK); preparing a fluorine-based polymer coating composition by mixing; and

A method for manufacturing a fluorine-based polymer coating film is provided, including forming a fluorine-based polymer coating film using the prepared fluorine-based polymer coating composition.

In the present invention, various types of compositions containing curing agents and solvents in appropriate ratios were prepared based on fluorine-based polymers with low surface energy, especially fluorine-based acrylic copolymers, and mechanical strength was improved through heat treatment after coating using the prepared composition. , a coating film with excellent stain resistance and chemical resistance was manufactured. As a result, for the manufactured coating film, surface energy < 17 mN/m, pencil hardness > 4H, acid resistance (HCl 25 wt% @RT, SUS substrate) > 300 hours, organic solvent stability (acetone solvent, 99%) > 170 It showed excellent performance in terms of time, etc.

Figure 1 is a graph measuring the change in the IR peak of the isocyanate group according to curing time and solvent and the time at which the isocyanate group drops to the minimum for each solvent.
Figure 2 (ac) shows the results of an acid resistance evaluation experiment according to the content of fluorine terminal monomers in the polymer. The signal in the graph means that heavy metals from the SUS304 substrate are melted through corrosion, and the dotted line indicates the reference point for corrosion judgment. (d) The peak of each graph is expressed as a function of integrated area time, and corrosion can be considered to have started from the point when the slope of the signal changes.
Figure 3 shows the UV-vis measurement method and corrosion determination criteria, (a) a model diagram of the sample measurement method, (b) a photograph of the solution in which corrosion occurred, and (c) the peak error due to device characteristics, and the curve in the graph shows These are the results of multiple measurements of a 25 wt% HCl solution in which no corrosion occurred. Errors may occur within about 0.1, and corrosion is judged when a signal greater than 0.1 is observed.
Figure 4 shows the UV-vis measurement results of samples coated to a thickness of 45 ㎛. The samples were prepared using solutions mixed with different mixing ratios of the curing agent, and the molar ratio of the hydroxyl group of the polymer and the isocyanate group of the curing agent was 100:90. , 100:110, 100:130, 100:150, 100:170, and this graph shows that all samples did not corrode for about 140 hours.
Figure 5 is a photograph showing a sample of a fluorine-based polymer coating film in which no problems occurred after completing the acetone resistance test;
Figure 6 is an evaluation of the hardness of the coating film through a pencil scratch test, and is a photograph showing (a) a case of scratching with 4 H, and (b) a case of scratching with 5 H.

In one aspect of the invention

Fluorine-based polymer; hardener; and solvent;

The fluorine-based polymer contains at least one functional group selected from the group consisting of an acrylate group, a carboxyl group, and a hydroxy group,

The curing agent contains an isocyanate group,

A fluorine-based polymer coating composition is provided as the solvent, which is a mixed solvent of propylene glycol methyl ether acetate (PGMEA) and methyl isobutyl ketone (MIBK).

Hereinafter, the fluorine-based polymer coating composition provided in one aspect of the present invention will be described in detail.

In the fluorine-based polymer coating composition of the present invention, the fluorine-based polymer may include an acrylate group, a carboxyl group, and a hydroxy group, and the fluorine-based polymer may include at least one hydroxy group.

The fluorine-based polymer may be a copolymer containing a monomer containing a fluorine terminal, a monomer containing an acrylate group, a monomer containing a carboxyl group, and a monomer containing a hydroxy group. For example, a fluorine-based polymer represented by the following formula (1) It can be.

[Formula 1]

(In Formula 1 above,

R _f is C _1-20 fluorinated straight-chain alkyl or C _3-20 fluorinated branched-chain alkyl;

R _1-4 are each independently hydrogen (H), methyl (CH ₃ ), or a halogen group;

R ₅ is straight-chain alkyl of C _1-20 or branched-chain alkyl of C _3-20 ;

Based on the weight ratio of x+y+p+q=100, x is 4-90, y is 4-90, p is 1-50, and q is 4-90;

z is 1-5.)

In the fluorine-based polymer represented by Formula 1, R _f may be expressed as -(CH ₂ ) _a (CF ₂ ) _b -F.

At this time, a may be an integer in the range of 1-10, an integer in the range of 1-7, or an integer in the range of 1-3. Additionally, b may be an integer in the range of 1-15, 1-10, 1-5, and most preferably 1-4.

In addition, for example, in the fluorine-based polymer represented by Formula 1, R ₁ , R ₂ , R ₃ and R ₄ may each independently be a hydrogen (H), methyl (CH ₃ ), or halogen group. The halogen group may be fluorine (F) or chlorine (Cl). Furthermore, in the fluorine-based polymer represented by Formula 1, R ₁ , R ₂ , R ₃ and R ₄ are preferably methyl.

Furthermore, for example, in the fluorine-based polymer represented by Formula 1, R ₅ may be represented as -(CH ₂ ) _c -CH ₃ .

At this time, c may be an integer in the range of 0-15, 1-10, or 1-5, but the range of the c value is not limited thereto.

In addition, as an example, in the fluorine-based polymer represented by Formula 1, x, y, p and q are based on a weight ratio of x+y+p+q=100, x is 4-90, y is 4-90, p is 1-10, q is 4-90.

The x may be 4-90, 10-80, 20-70, 30-60, 40-55, and is preferably 45-55.

Additionally, y may be 4-90, 10-80, 15-70, 20-50, 25-45, and preferably 30-40.

Furthermore, p may be 1-50, 1-30, 1-20, 1-15, and preferably 1-10.

Additionally, q may be 4-90, 5-70, 8-60, 10-40, and preferably 10-20.

Furthermore, p+q may be 70 or less, and may be 50 or less. By having a composition within the above range, it is possible to have lower surface energy and higher light transmittance, as well as high acid resistance and organic solvent stability, and at the same time, significantly higher pencil strength.

In addition, for example, the fluorine-based polymer represented by Formula 1 preferably has a number average molecular weight of 5,000-500,000, and more preferably 50,000-400,000. If the number average molecular weight of the fluorine-based polymer is less than 5,000, the thermal and mechanical strength of the polymer may decrease, and if it exceeds 500,000, the problem of rapidly decreasing solubility in organic solvents may occur.

Unlike generally known fluorine-based polymers, the polymer represented by Formula 1 is soluble in generally known organic solvents, so it has a very advantageous effect in the manufacturing process. Examples of the organic solvent include any general organic solvent such as chloroform, dichloromethane, acetone, pyridine, tetrahydrofuran, chlorobenzene, dichlorobenzene, etc., which can be used without any restrictions.

Additionally, as an example, the fluorine-based polymer provided in one aspect of the present invention may be represented by the following formula (2).

[Formula 2]

(In Formula 2 above,

R _f is C _1-20 fluorinated straight-chain alkyl or C _3-20 fluorinated branched-chain alkyl;

R ₁ , R ₂ ′, R ₂ ″, R ₃ and R ₄ are each independently a hydrogen (H), methyl (CH ₃ ) or halogen group;

R ₅ 'is C _2-20 straight-chain alkyl or C _3-20 branched-chain alkyl;

Based on the weight ratio of x+y′+y″+p+q=100, x is 4-90, y′ is 4-90, y″ is 4-90, p is 1-50, and q is 4-90;

z is 1-5).

As a specific example, in the fluorine-based polymer represented by Formula 2, R _f may be expressed as -(CH ₂ ) _a (CF ₂ ) _b -F.

At this time, a may be an integer in the range of 1-10, an integer in the range of 1-7, or an integer in the range of 1-3. Additionally, b may be an integer in the range of 1-15, 1-10, 1-5, and most preferably 1-4.

In addition, for example, in the fluorine-based polymer represented by Formula 2, R ₁ , R ₂ ′, R ₂ ″, R ₃ and R ₄ may each independently be a hydrogen (H), methyl (CH ₃ ), or halogen group. The halogen group may be fluorine (F) or chlorine (Cl). Furthermore, in the fluorine-based polymer represented by Formula 2, R ₁ , R ₂ ′, R ₂ ″, R ₃ and R ₄ are preferably methyl.

For example, in the fluorine-based polymer represented by Formula 2, R ₅ ′ may be represented as -(CH ₂ ) _d -CH ₃ .

At this time, d may be an integer in the range of 1-15, 1-10, or 1-5, but the range of the d value is not limited thereto.

In addition, as an example, in the fluorine-based polymer represented by Formula 2, x, y′, y″, p, and q are based on a weight ratio of x+y′+y″+p+q=100, and x is 4-90; y′ is 4-90, y″ is 4-90, p is 1-50, and q is 4-90.

The x may be 4-90, 10-80, 20-70, 30-60, 40-55, and is preferably 45-55.

In addition, y' may be 4-90, 10-70, 10-60, 15-50, 15-40, preferably 15-30, and 17- It is more preferable that it is 23, and it is preferable that it is 18-22.

Furthermore, y'' may be 4-90, 4-70, 4-60, 5-50, 6-40, 6-30, 6- It is preferably 20, more preferably 7-15, and more preferably 8-12.

Additionally, p may be 1-50, 1-30, 1-20, 1-15, and preferably 1-10.

Furthermore, q may be 4-90, 5-70, 8-60, 10-40, and preferably 10-20.

Additionally, p+q may be 70 or less, and may be 50 or less. By having a composition within the above range, it is possible to have lower surface energy and higher light transmittance, as well as high acid resistance and organic solvent stability, and at the same time, significantly higher pencil strength.

The fluorine-based polymer may contain 10 mol% to 75 mol%, 20 mol% to 70 mol%, and 25 mol% to 65 mol% of monomers containing fluorine terminals, relative to the total monomers, It may contain 30 mol% to 60 mol%, may contain 35 mol% to 55 mol%, may contain 40 mol% to 55 mol%, may contain 42 mol% to 53 mol%, and may contain 44 mol%. It may contain % to 50 mol%, may contain 45 mol% to 48 mol%, may contain 30 mol% to 65 mol%, may contain 35 mol% to 62 mol%, and may contain 40 mol% to 40 mol%. It may contain 60 mol%. Low surface energy can be secured by including a monomer containing a fluorine terminal within the above range.

In addition, the fluorine-based polymer may contain 5 mol% to 20 mol%, 7 mol% to 18 mol%, 8 mol% to 17 mol%, and 9 mol% of a monomer containing a carboxyl group. It may contain % to 16 mol%, and may contain 10 mol% to 15 mol%. By including a monomer containing a carboxyl group within the above range, high adhesion to substrates such as metal, glass, and plastic can be provided.

In the fluorine-based polymer coating composition of the present invention, the curing agent contains an isocyanate group. The fluorine-based polymer can form a coating film with stronger chemical and mechanical durability through a curing agent having an isocyanate group.

For example, the curing agent may be a hexamethylene diisocyanate timer series.

In the fluorine-based polymer coating composition, the molar ratio of the functional group contained in the fluorine-based polymer and the isocyanate group of the curing agent may be 100:50 to 100:300, 100:70 to 250, or 100:80 to 200, It can be 100:90-170, it can be 100:100-150, it can be 100:100-140, it can be 100:100-130, it can be 100:100-120, it can be 100:110-120 It can be 100:120~160, it can be 100:130~150, it can be 100:120~140, it can be 100:105~115. The content of the curing agent in the fluorine-based polymer coating composition can be an important variable in determining the degree of curing and physical properties. If a small amount is added, the degree of curing decreases and the mechanical and chemical properties deteriorate, and if an excessive amount is added, the mass of the entire coating film of the fluorine-based polymer decreases, so there is a problem of deterioration of the surface properties. The amount of isocyanate groups added is a molar ratio, and may be 100 to 120% or 130 to 150% of the total number of moles of hydroxy groups of the fluorine-based polymer.

In the fluorine-based polymer coating composition of the present invention, the solvent includes a mixed solvent of propylene glycol methyl ether acetate (PGMEA) and methyl isobutyl ketone (MIBK). The solvent not only dissolves the fluorine-based polymer and the curing agent, but also acts as a mobile phase for the curing agent. If the boiling point of the solvent is higher than the curing temperature of the hardener, the speed of the curing reaction slows down significantly, and the progress rate of the reaction also decreases. If curing is incomplete, the target physical properties cannot be obtained, such as the possibility of penetration by acid solutions, etc. If the boiling point of the solvent is too high, there is a possibility that it will remain in the coating film even after the curing reaction is completed or may become involved in the reaction.

The solvent may include 5 to 30 parts by weight of propylene glycol methyl ether acetate and 95 to 70 parts by weight of methyl isobutyl ketone, and 10 to 25 parts by weight of propylene glycol methyl ether acetate based on 100 parts by weight of the total solvent. and 90 to 75 parts by weight of methyl isobutyl ketone, 15 to 20 parts by weight of propylene glycol methyl ether acetate, and 85 to 80 parts by weight of methyl isobutyl ketone, and methyl propylene glycol It may include 5 to 10 parts by weight of ether acetate and 95 to 90 parts by weight of methyl isobutyl ketone. By applying a mixed solvent in the above range to the composition, the uniformity and production efficiency of the coating film can be improved, and the curing reaction can proceed quickly and reliably.

In the fluorine-based polymer coating composition of the present invention, the fluorine-based polymer coating composition may include 20 to 60 parts by weight of the fluorine-based polymer and the curing agent, and 25 to 50 parts by weight, based on 100 parts by weight of the total composition. and may contain 30 to 40 parts by weight.

In the present invention, the fluorine-based polymer coating composition formed by appropriately selecting a curing agent and solvent based on a fluorine-based polymer with low surface energy is a coating film with excellent mechanical strength, contamination resistance, and chemical resistance through heat treatment after coating using this composition. can be manufactured.

Additionally, in another aspect of the present invention

A fluorine-based polymer containing at least one functional group selected from the group consisting of an acrylate group, a carboxyl group, and a hydroxy group; A curing agent containing an isocyanate group; and a solvent that is a mixed solvent of propylene glycol methyl ether acetate (PGMEA) and methyl isobutyl ketone (MIBK). A method for producing a fluorine-based polymer coating composition comprising a step of mixing is provided. do.

The fluorine-based polymer coating composition of the present invention can be manufactured by mixing a fluorine-based polymer and a curing agent in a mixed solvent, and the mixing ratio can be the same as that in the fluorine-based polymer coating composition described above.

Furthermore, in another aspect of the present invention

A fluorine-based polymer coating film formed by coating the above-described fluorine-based polymer coating composition is provided.

The fluorine-based polymer coating film has a surface energy of 25 mN/m or less, 23 mN/m or less, 21 mN/m or less, 19 mN/m or less, 17 mN/m or less, preferably less than 17 mN/m, and 1 mN/m or less. It may be more than m.

The fluorine-based polymer coating film may have a pencil hardness of 3 H or more, 4 H or more, preferably more than 4 H and 5 H or less.

The acid resistance of the fluorine-based polymer coating film may be such that it does not corrode for more than 100 hours when immersed in 25 wt% hydrochloric acid (HCl) at room temperature, may not corrode for more than 200 hours, and does not corrode for more than 300 hours. It may be one that does not corrode for a time exceeding 300 hours, and may preferably not corrode for a time of 600 hours or less.

The fluorine-based polymer coating film may not peel off for more than 120 hours when immersed in an acetone solvent with an organic solvent stability of 99%, may not peel off for more than 140 hours, and may not peel off for more than 160 hours, It may not peel off for more than 170 hours, and preferably, it may not peel off for more than 170 hours and may not peel off for less than 600 hours.

In addition, in another aspect of the present invention

A fluorine-based polymer containing at least one functional group selected from the group consisting of an acrylate group, a carboxyl group, and a hydroxy group; A curing agent containing an isocyanate group; and a solvent, which is a mixed solvent of propylene glycol methyl ether acetate (PGMEA) and methyl isobutyl ketone (MIBK); preparing a fluorine-based polymer coating composition by mixing; and

A method for manufacturing a fluorine-based polymer coating film is provided, including forming a fluorine-based polymer coating film using the prepared fluorine-based polymer coating composition.

In the method for producing a fluorine-based polymer coating film of the present invention, a fluorine-based polymer containing at least one functional group selected from the group consisting of an acrylate group, a carboxyl group, and a hydroxy group; A curing agent containing an isocyanate group; The step of preparing a fluorine-based polymer coating composition by mixing a solvent, which is a mixed solvent of propylene glycol methyl ether acetate (PGMEA) and methyl isobutyl ketone (MIBK), prepares a general curable composition. It can be manufactured by this method.

The method for producing a fluorine-based polymer coating film of the present invention includes the step of forming a fluorine-based polymer coating film using the prepared fluorine-based polymer coating composition, and the formation of the fluorine-based polymer coating film is performed using the fluorine-based polymer coating composition through spin coating, dip coating, A variety of methods can be performed, including roll coating, solution coating and spray coating.

Hereinafter, the present invention will be described in detail through examples and experimental examples.

However, the following examples and experimental examples are only for illustrating the present invention, and the content of the present invention is not limited by the following examples and experimental examples.

<Preparation Examples 1 to 4> Preparation of polymer-1 to 4

To prepare a fluorine-based polymer coating composition according to an embodiment, as model polymers, PFPMA (pentafluoropropyl methacrylate), MMA (methyl methacrylate), SMA (stearyl methacrylate), HEMA (hydroxyethyl methacrylate), and MAA (methacrylic acid) were copolymerized. A fluorine-based acrylic copolymer was prepared. Add 50 wt% of monomers to a solvent (tetrahydrofuran, 2-butanon, methyl isobutyl ketone, propylene glycol methyl ether acetate, etc.) that mixes well with the added monomers as well as the polymer after synthesis, and then heat to 60 degrees under a nitrogen atmosphere. . Once the temperature is stable, AIBN (azobis isobutyro nitrile) is added as an initiator and allowed to react for about 8 hours. After the reaction proceeds, the temperature is raised to 80℃ and refluxed for 2 hours to remove residual radicals, and then slowly cooled to room temperature.

The above solvent can be used without particular restrictions, but considering the combination with the curing agent and the coating process to be described below, it is preferable to use a solvent with a relatively low boiling point (tetrahydrofuran, 2-butanon, methyl isobutyl ketone) as the synthetic solvent.

PFPMA, a monomer containing a fluorine terminal, was added at 0 mol%, 25 mol%, 46 mol%, and 60 mol%, respectively, relative to the total monomers, to produce the non-fluorine polymer (P0) and fluorine polymer (P25, P46) of Preparation Examples 1 to 4. and P60) were prepared.

The yield measured after the purification process for the polymer solution obtained after polymerization was measured in the range of 80% to 90% depending on the solvent.

<Experimental Example 1> Analysis of manufactured polymer

In order to confirm whether the polymers prepared in Preparation Examples 2 to 4 were produced normally, the composition of the fluorinated acrylic copolymer obtained through nuclear magnetic resonance spectroscopy (NMR) using CDCl ₃ as a solvent was confirmed through the integration ratio of the peak. . For a representative sample, the monomer input ratio (mol%) is 4.6 : 1.2 : 2 : 1.2 : 2.3, and the composition obtained through H-NMR peak integration after synthesis is x : y : z : p : q = 4.4 : 1.02 : 2 : It was 1.34:2.05. x. y, z, p, and q refer to PFPMA, MM, SMA, MAA, and HEMA, respectively. Through this, it can be confirmed that the fluorine-based acrylic copolymer prepared according to the mole percentage of the monomers added shows a similar mole percentage.

In addition, as a result of gel permeation chromatography (GPC) measurement, it was confirmed that the polymer synthesized through the above reaction had a molecular weight in the range of 70,000 to 90,000.

<Example 1> Preparation of fluorine-based polymer coating composition-1

The fluorine-based acrylic copolymer prepared in the above production example, and MEKO HDI trimer (methylethyl keoxime blocked hexamethylene diisocyanate trimer), propylene glycol methyl ether acetate (PGMEA), and methyl as a HDI trimer (hexamethylene diisocyanate trimer) series hardener. A fluorine-based polymer coating composition was prepared by adding isobutyl ketone (MIBK) to a mixed solvent (PGMEA/MIBK).

At this time, the fluorinated acrylic copolymer used was P46 prepared in Preparation Example 3, and the molar ratio of the hydroxy group of the fluorinated acrylic copolymer and the isocyanate group of the curing agent was mixed to 100:110, and the ratio of the mixed solvent was PGMEA: MIBK was set to 20:80.

<Example 2> Preparation of fluorine-based polymer coating composition-2

A fluorine-based polymer coating composition was prepared in the same manner as in Example 1, except that the ratio of mixed solvents, PGMEA:MIBK, was 10:90.

<Example 3> Preparation of fluorine-based polymer coating composition-3

A fluorine-based polymer coating composition was prepared in the same manner as in Example 1, except that the ratio of mixed solvents, PGMEA:MIBK, was 5:95.

<Example 4> Preparation of fluorine-based polymer coating composition-4

A fluorine-based polymer coating composition was prepared in the same manner as in Example 1, except that P25 prepared in Preparation Example 2 was used as the fluorine-based acrylic copolymer.

<Example 5> Preparation of fluorine-based polymer coating composition-5

A fluorine-based polymer coating composition was prepared in the same manner as in Example 1, except that P60 prepared in Preparation Example 2 was used as the fluorine-based acrylic copolymer.

<Example 6> Preparation of fluorine-based polymer coating composition-6

A fluorine-based polymer coating composition was prepared in the same manner as in Example 1, except that the hydroxyl group of the fluorine-based acrylic copolymer and the isocyanate group of the curing agent were mixed in a molar ratio of 100:90.

<Example 7> Preparation of fluorine-based polymer coating composition-7

A fluorine-based polymer coating composition was prepared in the same manner as in Example 1, except that the hydroxyl group of the fluorine-based acrylic copolymer and the isocyanate group of the curing agent were mixed in a molar ratio of 100:130.

<Example 8> Preparation of fluorine-based polymer coating composition-8

A fluorine-based polymer coating composition was prepared in the same manner as in Example 1, except that the hydroxy group of the fluorine-based acrylic copolymer and the isocyanate group of the curing agent were mixed in a molar ratio of 100:150.

<Example 9> Preparation of fluorine-based polymer coating composition-9

A fluorine-based polymer coating composition was prepared in the same manner as in Example 1, except that the hydroxyl group of the fluorine-based acrylic copolymer and the isocyanate group of the curing agent were mixed in a molar ratio of 100:170.

<Comparative Example 1> Coating composition using non-fluorinated polymer

A fluorine-based polymer coating composition was prepared in the same manner as in Example 1, except that P0 prepared in Preparation Example 1 was used as the fluorine-based acrylic copolymer.

<Comparative Example 2> Coating composition using MEK solvent

A fluorine-based polymer coating composition was prepared in the same manner as in Example 1, except that methyl ethyl ketone (MEK) was used as the solvent instead of a mixed solvent.

<Comparative Example 3> Coating composition using PGMEA solvent

A fluorine-based polymer coating composition was prepared in the same manner as in Example 1, except that propylene glycol methyl ether acetate (PGMEA) was used as the solvent instead of a mixed solvent.

The compositions of Examples 1 to 9 and Comparative Examples 1 to 3 are shown in Table 1 below.

Fluorine terminal monomer content (mol%) Organic Solvent Types Organic solvent mixing ratio (volume ratio) Hardener type Ratio (molar ratio) of NCO of curing agent to OH of fluorine-based polymer Example 1 46 PGMEA/MIBK 20:80 MEKO HDI trimmer 100:110 Example 2 46 PGMEA/MIBK 10:90 MEKO HDI trimmer 100:110 Example 3 46 PGMEA/MIBK 5:95 MEKO HDI trimmer 100:110 Example 4 25 PGMEA/MIBK 20:80 MEKO HDI trimmer 100:110 Example 5 60 PGMEA/MIBK 20:80 MEKO HDI trimmer 100:110 Example 6 46 PGMEA/MIBK 20:80 MEKO HDI trimmer 100:90 Example 7 46 PGMEA/MIBK 20:80 MEKO HDI trimmer 100:130 Example 8 46 PGMEA/MIBK 20:80 MEKO HDI trimmer 100:150 Example 9 46 PGMEA/MIBK 20:80 MEKO HDI trimmer 100:170 Comparative Example 1 0 PGMEA/MIBK 20:80 MEKO HDI trimmer - Comparative Example 2 46 MEK - MEKO HDI trimmer 100:110 Comparative Example 3 46 PGMEA - MEKO HDI trimmer 100:110

<Experimental Example 1> Analysis of changes in composition according to solvent

In order to confirm the effect of the solvent of the fluorine-based polymer coating composition of the present invention, the isocyanate (NCO) peak according to curing temperature and curing time was measured using the compositions prepared in Examples 1 to 3, Comparative Example 2, and Comparative Example 3. The change was confirmed through IR measurement, and the results are shown in Figure 1.

As shown in Figure 1, it was confirmed that when MEK or PGMEA alone was used as a solvent, curing was completed at high temperature for several tens of hours. On the other hand, when applying the PGMEA/MIBK mixed solvent, it can be seen that the curing time is greatly shortened.

Based on the above results, this study found that it is difficult to apply pure solvents such as MEK and PGMEA, and that only by applying a PGEMA/MIBK mixed solvent can an excellent coating film be formed by shortening the curing time of the fluorine-based polymer coating composition. .

<Experimental Example 2> Characteristic analysis of polymer coating film

In order to confirm the characteristics of the fluorine-based polymer coating film manufactured using the fluorine-based polymer coating composition of the present invention, surface energy, acid resistance, organic solvent resistance (acetone resistance), and pencil hardness were analyzed.

For the sample for surface energy measurement, a 30 wt% solution was applied on a cleaned silicon wafer, spin-coated at 2000 rpm, and cured at 150 degrees for 5 hours to produce a polymer coating film.

The sample for the acid resistance test was produced by dip-coating a 45 × 45 × 3t mm ³ metal specimen made of SUS304 with a 40 wt% solution. The thickness of the film increases linearly in proportion to the number of dip coatings, and in order to test the effect of the amount of fluorine monomer on acid resistance, a sample coated with a thickness of 22 ㎛ was used to check the effect of the amount of hardener on long-term acid resistance. For this purpose, samples coated with a thickness of 44 ㎛ were prepared.

1) Surface energy analysis

The surface energy of the polymer coating film was calculated using the Owens-Wendt-Rabel-Kaelble (OWRK) method after measuring the contact angle using water and diiodomethane (DIM) as solvents (KRUSS DSA100S).

The change in surface energy of the polymer resin was measured according to the input ratio of the fluorine-based monomer, and the results are shown in Table 2.

In addition, the change in surface energy according to the amount of curing agent added to the fluorine-based polymer P46 (copolymer with a fluorine monomer content of 46 mol%) was observed, and the results are shown in Table 3.

Fluorine monomer content [mol%] Water contact angle [ ^o ] DIM contact angle [ ^o ] Surface energy [mN/m] Comparative Example 1 0 94.9 52.4 32.9 Example 4 25 100 70.4 22.8 Example 1 46 101.7 77.3 19.3 Example 5 60 104.9 80.9 17.3

OH: NCO [mol%] Water contact angle [ ^o ] DIM contact angle [ ^o ] Surface energy [mN/m] Example 6 100:90 101.6 74.9 20.4 Example 1 100:110 101.7 77.3 19.3 Example 7 100:130 102.8 75.7 20.0 Example 8 100:150 102.3 75.8 20.9 Example 9 100:170 102.6 73.8 20.9

As shown in Table 2, it can be confirmed that the surface energy is high when a non-fluorine-based acrylic copolymer containing no fluorine-terminated monomer is formed as a coating film (Comparative Example 1). On the other hand, when applying a fluorine-based acrylic copolymer, it was confirmed that the surface energy was lowered to at least 17.3 mN/m, and it was clearly observed that the surface energy decreased as the fluorine terminal monomer content increased. In addition, as shown in Table 3, when the molar ratio of the hydroxyl group of the fluorine-based acrylic copolymer and the isocyanate group in the curing agent is mixed at 100:90, it can be seen that the surface energy is somewhat high due to the remaining hydroxyl group. : When mixed at a ratio of 110 or higher, the surface energy tends to decrease slightly as the hardener increases. In particular, it was confirmed that significantly lower surface energy could be secured when mixed at a ratio of 100:110. This is the result of an increase in surface energy because when the curing agent is insufficient, hydroxyl groups remain in the coating film, and when the curing agent is excessive, the mass ratio of the fluorinated portion that lowers the surface energy decreases.

2) Acid resistance analysis

To evaluate acid resistance, a 25 wt% high-concentration hydrochloric acid aqueous solution was prepared and a coating film prepared from the composition of each Example and Comparative Example was added, and the hydrochloric acid solution was periodically collected and UV-Vis measurement was performed. When the SUS304 substrate is exposed to acid, a peak is detected as heavy metals such as chromium precipitate, and the hydrochloric acid solution turns yellow. By observing this, it was evaluated whether the polymer coating was protecting the SUS304 substrate.

First, in the case of coating films prepared with the compositions of Example 1, Example 4, Example 5, and Comparative Example 1, the film was coated to 22 ㎛ as described above, and the effect of the input amount of fluorine-terminated monomer on acid resistance was measured. The results are shown in Figures 2 and 3. Due to structural errors in the measuring device, there are cases where a signal is visible even if corrosion does not progress, but a result of 0.1 or less indicates noise (see Figure 3).

As shown in Figure 2, the coating film formed using the composition of Example 5 had poor adhesion to the metal substrate due to the high content of fluorine-terminated monomers, and as a result, corrosion of the metal substrate occurred less than an hour after the measurement began. This was observed. Corrosion of the coating film formed using the composition of Example 4 was also observed after 3.5 hours, and a signal exceeding the noise range was observed. The coating films formed using the compositions of Comparative Example 1 and Example 1 were all able to protect the metal substrate from acid for more than a day, but in the case of Comparative Example 1, it was found that corrosion progressed very rapidly after 35 hours. On the other hand, in the case of Example 1, corrosion did not appear even after 55 hours, confirming that the acid resistance was significantly excellent.

In addition, in the case of the coating film prepared with the composition of Example 1 and Examples 6 to 9, as described above, the film was coated to a thickness of about 45 ㎛, and the effect of the amount of curing agent on acid resistance was measured. The results are shown in Figure 4. It was.

As shown in Figure 4, even after about 140 hours or more, no signal above the corrosion baseline (0.1) was detected, indicating that all examples had high acid resistance without any problems.

3) Organic solvent resistance (acetone resistance) analysis

To evaluate the organic solvent resistance of the polymer coating film, the composition of Example 1 was used to coat a stainless steel specimen to a thickness of 20 ㎛. This sample was cured at high temperature for a sufficient period of time, and after curing, the specimen was immersed in acetone (99%). The results of observation after being left for one week (approximately 170 hours) are shown in Figure 5.

As shown in Figure 5, it was confirmed that no peeling occurred in the coating film manufactured using the composition presented in the present invention.

Since the cured coating film does not dissolve in acetone due to its high molecular weight, it can be determined that the peeling phenomenon occurs when a hole is formed in the coating layer and acetone seeps into it. Through the above experimental results, it can be seen that the coating film developed in the present invention has strong resistance to organic solvents such as acetone.

4) Pencil hardness analysis

The mechanical durability of the polymer coating film was evaluated by measuring pencil hardness. The composition of Example 1 was coated on a stainless steel specimen to a thickness of 35 ㎛ m and cured. Afterwards, the specimen was scratched while applying a constant 1 kg load to the pencil. The hardness of the pencil was increased step by step starting from 3 H, and the scratched trace was observed under a microscope. The results are shown in Figure 6.

As shown in Figure 6, peeling occurred at 5 H, and through this, the hardness of the fluorine-based polymer coating film of the present invention is about 4 H or more, exceeds 4 H, and exists between 4 H and 5 H. And it was found.

Claims (12)

fluorine-based polymer; hardener; and solvent;
The fluorine-based polymer is represented by the formula below,
The curing agent contains an isocyanate group,
The solvent is a fluorine-based polymer coating composition that is a mixed solvent of propylene glycol methyl ether acetate (PGMEA) and methyl isobutyl ketone (MIBK):
[Chemical formula]

(In the above formula,
R _f is C _1-20 fluorinated straight-chain alkyl or C _3-20 fluorinated branched-chain alkyl;
R ₁ , R ₂ ′, R ₂ ″, R ₃ and R ₄ are each independently a hydrogen (H), methyl (CH ₃ ) or halogen group;
R ₅ 'is straight-chain alkyl of C _2-20 or branched-chain alkyl of C _3-20 ;
Based on the weight ratio of x+y′+y″+p+q=100, x is 4-90, y′ is 4-90, y″ is 4-90, p is 1-50, and q is 4-90;
z is 1-5). delete According to paragraph 1,
Wherein x is 10-75, a fluorine-based polymer coating composition. According to paragraph 1,
Wherein p is 5-20, a fluorine-based polymer coating composition. According to paragraph 1,
A fluorine-based polymer coating composition in which the curing agent is a hexamethylene diisocyanate trimer-based curing agent. According to paragraph 1,
The solvent is a fluorine-based polymer coating composition comprising 5 to 30 parts by weight of propylene glycol methyl ether acetate and 95 to 70 parts by weight of methyl isobutyl ketone, based on 100 parts by weight of the total solvent. According to paragraph 1,
The fluorine-based polymer coating composition is a fluorine-based polymer coating composition comprising 20 to 60 parts by weight of a fluorine-based polymer and a curing agent based on 100 parts by weight of the total composition. According to paragraph 1,
The fluorine-based polymer coating composition,
A fluorine-based polymer coating composition in which the molar ratio of the functional group contained in the fluorine-based polymer and the isocyanate group of the curing agent is 100:50 to 100:300. A fluorine-based polymer represented by the formula below; A curing agent containing an isocyanate group; and a solvent that is a mixed solvent of propylene glycol methyl ether acetate (PGMEA) and methyl isobutyl ketone (MIBK). Method for producing a fluorine-based polymer coating composition comprising:
[Chemical formula]

(In the above formula,
R _f is C _1-20 fluorinated straight-chain alkyl or C _3-20 fluorinated branched-chain alkyl;
R ₁ , R ₂ ′, R ₂ ″, R ₃ and R ₄ are each independently a hydrogen (H), methyl (CH ₃ ) or halogen group;
R ₅ 'is straight-chain alkyl of C _2-20 or branched-chain alkyl of C _3-20 ;
Based on the weight ratio of x+y′+y″+p+q=100, x is 4-90, y′ is 4-90, y″ is 4-90, p is 1-50, and q is 4-90;
z is 1-5). A fluorine-based polymer coating film formed by coating the fluorine-based polymer coating composition of claim 1. According to clause 10,
The fluorine-based polymer coating film has a surface energy of 17 mN/m or less, a pencil hardness of 4 H or more, and acid resistance that does not corrode for more than 300 hours when immersed in 25 wt% hydrochloric acid (HCl) at room temperature, and is resistant to organic solvents. A fluorine-based polymer coating film that is stable and does not peel off for more than 170 hours when immersed in 99% acetone solvent. Preparing the fluorine-based polymer coating composition of claim 1; and
A method for producing a fluorine-based polymer coating film comprising: forming a fluorine-based polymer coating film using the prepared fluorine-based polymer coating composition.