JP2020196782A - Crosslinking agent - Google Patents

Abstract

To provide a crosslinking agent capable of preparing a cured product having excellent adhesiveness with a substrate and maintaining antimicrobial properties.SOLUTION: There is provided a crosslinking agent containing a compound represented by the following general formula (1): (wherein, A is an (m+n+2)valent alcohol residue having 1 to 6 carbon atoms, B is a substituent represented by the following general formula (3) or the like, R1 is a hydrocarbon group having 1 to 6 carbon atoms, R2 is a hydrogen atom or a hydrocarbon group having 1 to 4 carbon atoms, X is a counter ion of a quaternary ammonium group, a chloride ion, a bromide ion, a sulfate ion, a nitrate ion, a phosphate ion or a hydroxide ion, m and n are independently an integer of 0 to 4, m and n bonded to the same substituent satisfy 0≤m+n≤4, l is 1 to 6 and k is an integer of 1 or more.)SELECTED DRAWING: None

Description

The present invention relates to a cross-linking agent. More specifically, the present invention relates to a cross-linking agent that imparts sustained antibacterial properties to a curable resin.

In recent years, antibacterial and antiviral coating films have been applied to a wide variety of products with the increase in awareness of hygiene and aesthetics in the living environment. Generally, as a method of adding antibacterial and antiviral properties to a coating film, a method of forming a coating film using a coating material to which an amount of a quaternary ammonium salt is added as an active ingredient is known. Further, a method of kneading a quaternary ammonium salt into a resin is also known in order to impart antibacterial performance to the plastic. However, in the coating film or plastic obtained by the method of adding these quaternary ammonium salts, there is a problem that the quaternary ammonium salts are gradually eluted and the antibacterial and antiviral properties are difficult to maintain.

As a method for solving this problem, by adding a polyvalent carboxylic acid together with the quaternary ammonium salt to the coating film, the quaternary ammonium salt is suppressed from eluting from the coating film to form an antibacterial / antiviral coating film. A method has been reported (Patent Document 1). However, this method does not completely immobilize the quaternary ammonium structure in the coating film, and is not sufficient as a method for maintaining antibacterial and antiviral properties.

On the other hand, as a cross-linking agent having a quaternary ammonium structure, it is known that a reaction product of a secondary amine compound and epihalohydrin is used as a water-absorbent resin cross-linking agent (Patent Document 2). However, as a result of the studies by the inventors, it was found that when the quaternary ammonium compound is used as a cross-linking agent for a resin composition, it easily aggregates with a curable resin and is not suitable for use as a coating agent or the like. Moreover, the antibacterial property of the water-absorbent resin cross-linking agent has not been investigated.

Japanese Unexamined Patent Publication No. 2015-67658 JP-A-2002-60544

An object of the present invention is to provide a cross-linking agent capable of producing a cured product having excellent adhesion to a substrate and maintaining antibacterial properties.

The present inventors have excellent coating stability, excellent adhesion to a substrate, and antibacterial properties of the obtained cured product, without causing agglomeration of a cross-linking agent having a specific structure together with the curable resin. We found that the cross-linking agent of the present invention was completed.

（一般式（１）中、Ａは（ｍ＋ｎ＋２）価の炭素数１〜６の多価アルコール残基を表し、Ｂは下記一般式（２）：

又は一般式（３）：

で表される置換基を表し、Ｒ^１は炭素数１〜６の炭化水素基を表し、Ｒ^２は水素原子又は炭素数１〜４の炭化水素基を表し、Ｘは４級アンモニウム基の対イオンであって塩化物イオン、臭化物イオン、硫酸イオン、硝酸イオン、リン酸イオン、又は水酸化物イオンを表し、ｍ、ｎはそれぞれ独立して０〜４の整数を表し、同じ置換基Ａに結合しているｍ、ｎは０≦ｍ＋ｎ≦４を満たし、ｌは１〜６であり、ｋは１以上の整数である。）
で表される化合物を含む架橋剤に関する。 That is, the present invention has the following general formula (1):

(In the general formula (1), A represents a (m + n + 2) -valent multivalent alcohol residue having 1 to 6 carbon atoms, and B represents the following general formula (2):

Or general formula (3):

Represents a substituent represented by, R ¹ represents a hydrocarbon group having 1 to 6 carbon atoms, R ² represents a hydrogen atom or a hydrocarbon group having 1 to 4 carbon atoms, and X represents a pair of quaternary ammonium groups. Ions represent chloride ions, bromide ions, sulfate ions, nitrate ions, phosphate ions, or hydroxide ions, and m and n each independently represent an integer of 0 to 4 and have the same substituent A. The combined m and n satisfy 0 ≦ m + n ≦ 4, l is 1 to 6, and k is an integer of 1 or more. )
The present invention relates to a cross-linking agent containing a compound represented by.

It is preferable that R ¹ is a methyl group.

It is preferable that m and n satisfy 0 ≦ m + n ≦ 1.

The present invention also relates to a curable resin and a curable resin composition containing the cross-linking agent.

Further, in the present invention, the following steps 1 to 3:
(Step 1) The following general formula (4):
A- (OH) _{m + 2} (4)
(In the general formula (4), A represents a (m + n + 2) -valent polyhydric alcohol residue having 1 to 6 carbon atoms, m and n represent an integer of 0 to 4, and 0 ≦ m + n ≦ 4 are satisfied.) The step of reacting a (m + n + 2) -valent polyhydric alcohol represented by (m + n + 2) with epihalohydrin,
(Step 2) The reaction product obtained in Step 1 and the following general formula (5):
R ¹ ₂ NH (5)
(In the general formula (5), R ¹ represents a hydrocarbon group having 1 to 6 carbon atoms.) A step of reacting with a secondary amine represented by the general formula (5), and
(Step 3) The cross-linking agent comprising a step of converting a halogen atom in the reaction product obtained in step 2 into -OR ² groups (R ² represents a hydrogen atom or a hydrocarbon group having 1 to 4 carbon atoms). Regarding the manufacturing method of.

The cross-linking agent of the present invention imparts long-lasting antibacterial properties to a cured product with a curable resin. Further, this cross-linking agent does not cause aggregation together with the curable resin, has excellent liquid coating stability, and when used as a coating agent, has excellent adhesion to a substrate.

で表される化合物を含む架橋剤に関する。 (1) Crosslinking agent The present invention has the following general formula (1):

The present invention relates to a cross-linking agent containing a compound represented by.

In the general formula (1), A represents a (m + n + 2) -valent polyhydric alcohol residue having 1 to 6 carbon atoms. m and n each independently represent an integer of 0 to 4, m and n bonded to the same substituent A satisfy 0 ≦ m + n ≦ 4, m + n is preferably 0 to 2, and 0 to 1 is more. preferable. Specific examples of the multivalent alcohol in the polyhydric alcohol residue will be described later.

In the general formula (1), R ¹ represents a hydrocarbon group having 1 to 6 carbon atoms, preferably 1 to 3 carbon atoms. Specific examples thereof include a methyl group, an ethyl group, a propyl group and an isopropyl group, and a methyl group and an ethyl group are preferable.

In the general formula (1), R ² represents a hydrogen atom or a hydrocarbon group having 1 to 4 carbon atoms. Specific examples thereof include hydrogen atom, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, sec-butyl group, isobutyl group and tert-butyl group, and hydrogen atom, methyl group and ethyl group. Is preferable.

In the general formula (1), X is a counterion of a quaternary ammonium group and represents a chloride ion, a bromide ion, a sulfate ion, a nitrate ion, a phosphate ion, or a hydroxide ion. Further, in the general formula (1), l is 1 to 6. k represents the number of counterions of the quaternary ammonium group and is an integer of 1 or more. The number of quaternary ammonium groups and k in the cross-linking agent are the same.

又は下記一般式（３）：

で表される置換基を表す。
一般式（２）及び一般式（３）において、Ｒ^１、Ｒ^２、Ａ、ｍ、ｎは一般式（１）について述べたのと同様である。一般式（２）及び一般式（３）の構造は、一般式（１）の化合物１分子中にそれぞれ２以上存在していてもよい。 In the general formula (1), B is a hydroxyl group or the following general formula (2):

Or the following general formula (3):

Represents a substituent represented by.
In the general formula (2) and the general formula (3), R ¹ , R ² , A, m, and n are the same as those described for the general formula (1). Two or more structures of the general formula (2) and the general formula (3) may be present in one molecule of the compound of the general formula (1), respectively.

(2) Method for producing a cross-linking agent The above-mentioned cross-linking agent has the following general formula (4):
A- (OH) _{m + n + 2} (4)
Step 1 of reacting a (m + n + 2) -valent polyhydric alcohol represented by (m + n + 2) with epihalohydrin,
The reaction product obtained in the above step 1 and the following general formula (5):
R ¹ ₂ NH (5)
It is produced by a production method including a step 2 of reacting a secondary amine represented by the above step 2 and a step 3 of converting a halogen atom in the reaction product obtained in the step 2 into -OR ² groups.

In the general formula (4), A represents a polyhydric alcohol residue having a (m + n + 2) valence of 1 to 6 carbon atoms, and m and n each independently represent an integer of 0 to 4, and are bonded to the same substituent A. M and n satisfy 0 ≦ m + n ≦ 4. m + n is preferably 0 to 2, more preferably 0 to 1. Examples of the polyhydric alcohol in the polyhydric alcohol residue include ethylene glycol, diethylene glycol, propylene glycol, triethylene glycol, 1,3-propanediol, dipropylene glycol, glycerin, diglycerin, 2-butane-1,4-diol, and the like. 1,3-Butanediol, 1,4-Butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,2-cyclohexanedimethanol, 1,2-cyclohexanediol, trimethylpropane, diethanolamine, tri Ethanolamine, pentaerythritol, sorbitol can be mentioned. Of these, ethylene glycol, diethylene glycol, glycerin, diglycerin and the like are preferable. These may be used alone or in combination of two or more.

Specific examples of the secondary amine represented by the general formula (5) include dimethylamine, diethylamine, methylethylamine, dipropylamine, and diisopropylamine. Among them, dimethylamine and diethylamine are preferable, and dimethylamine is preferable. More preferred. These may be used alone or in combination of two or more.

Specific examples of epichlorohydrin include epichlorohydrin, epibromohydrin, and α-methylepichlorohydrin. Of these, epichlorohydrin is preferable because it is easily available. These may be used alone or in combination of two or more.

In step 1, it is preferable to react 0.2 to 2 equivalents of epihalohydrin with 1 equivalent of the hydroxyl group of the polyhydric alcohol, and more preferably 0.3 to 1.5 equivalents. If the amount is less than 0.2 equivalent, the number of halohydrin groups in the obtained halohydrin compound is small, so that the quaternary ammonium structure in the cross-linking agent obtained in the subsequent step may be reduced and sufficient antibacterial activity may not be exhibited. If it exceeds, unreacted epihalohydrin may remain in the obtained halohydrin compound, which is not preferable from the viewpoint of safety.

In step 1, a catalyst can be used for the reaction of the polyhydric alcohol with epihalohydrin. Examples of such a catalyst include boron trifluoride diethyl ether complex, boron trifluoride butyl ethyl ether complex, boron trifluoride methanol complex, boron trifluoride ethylamine complex, boron trifluoride piperidine complex, zinc booxide, and houf. Examples thereof include Lewis acid catalysts such as copper, tin dichloride, tin tetrachloride, and aluminum chloride. The reaction temperature of the polyhydric alcohol and epihalohydrin is preferably 30 to 200 ° C, more preferably 50 to 100 ° C.

（一般式（６）中、Ａは（ｍ＋ｎ＋２）価の炭素数１〜６の多価アルコール残基を表し、Ｂは下記一般式（７）：

又は下記一般式（８）

で表される置換基を表し、Ｒ^１は炭素数１〜６の炭化水素基を表し、Ｘは４級アンモニウム基の対イオンであって塩化物イオン、臭化物イオン、又は水酸化物イオンを表し、ｍ、ｎはそれぞれ独立して０〜４の整数を表し、同じ置換基Ａに結合しているｍ、ｎは０≦ｍ＋ｎ≦４を満たし、ｌは１〜６であり、ｋは１以上の整数である。）
で表される化合物が得られる。 The reaction mechanism in steps 1 and 2 will be described with reference to an example of using epichlorohydrin as epihalohydrin. In step 1, a chlorohydrin ether compound having two or more chlorohydrin groups is obtained by reacting the hydroxyl group of the polyhydrin represented by the general formula (4) with epichlorohydrin. When a secondary amine represented by the general formula (5) is added thereto in step 2, the amine reacts with the chlorohydrin group and the general formula (6):

(In the general formula (6), A represents a (m + n + 2) -valent multivalent alcohol residue having 1 to 6 carbon atoms, and B represents the following general formula (7):

Or the following general formula (8)

Represents a substituent represented by, R ¹ represents a hydrocarbon group having 1 to 6 carbon atoms, and X is a counter ion of a quaternary ammonium group and represents a chloride ion, a bromide ion, or a hydroxide ion. , M and n each independently represent an integer of 0 to 4, m and n bonded to the same substituent A satisfy 0 ≦ m + n ≦ 4, l is 1 to 6, and k is 1 or more. Is an integer of. )
The compound represented by is obtained.

In step 2, it is preferable to react 0.05 to 1 equivalent of the secondary amine represented by the general formula (5) with 1 equivalent of the halohydrin group contained in the halohydrin ether compound, preferably 0.1 to 0. It is more preferable to react by an equivalent amount of 5.5. If it is less than 0.05 equivalents, sufficient antibacterial properties may not be exhibited due to the small amount of quaternary ammonium structure in the obtained cross-linking agent, and if it exceeds 1 equivalent, unreacted secondary amines may remain. It is not preferable from the viewpoint of safety.

In the compound of the general formula (6) obtained in step 2, the halohydrin group remains at the terminal. In step 3, the halogen atom of this halohydrin group is converted into OR ² groups. Examples of the method for converting a halogen atom to OR ² groups include a method of hydrolyzing a halogen atom, a method of converting to an epoxy compound and then hydrolyzing in an alcohol solvent, and a method of converting a halogen atom to another desorbing group. A method of post-hydrolysis can be mentioned. In step 3, the halogen atom is usually converted to a hydroxyl group, in which case R ² becomes a hydrogen atom. On the other hand, a part or all of the halogen atoms may react with the alcohol solvent to be converted into an alkoxy group, in which case R ² becomes a hydrocarbon group having 1 to 4 carbon atoms. For example, when step 3 is carried out using methanol as a solvent, the halogen atom is converted into a hydroxyl group or a methoxy group, and R ² becomes a hydrogen atom or a methyl group.

After step 3, sulfuric acid, nitric acid or phosphoric acid may be added to adjust the pH of the aqueous solution. The sulfate ion, nitrate ion, and phosphate ion added in these steps become counterions of quaternary ammonium groups in the cross-linking agent of the present invention, and are represented by X in the compound of the general formula (1). Other examples of the counterion of the quaternary ammonium group include chloride ion and bromide ion derived from epihalohydrin added in step 1, and hydroxide ion.

(3) Curable Resin Composition The present invention also relates to a curable resin composition containing the curable resin and the above-mentioned cross-linking agent.

A curable resin is a compound that cures by proceeding with a cross-linking reaction with the above-mentioned cross-linking agent by heat (including normal temperature), catalyst, light (ultraviolet rays, etc.), electron beam, etc., and has a carboxylic acid group in the molecule. It is preferable to have at least one functional group selected from a carboxylic acid base, a hydroxyl group, an epoxy group, an isocyanate group, and an amino group. Specific examples thereof include melamine resin, acrylic resin, epoxy resin, polyester resin and polyurethane resin. Among these, melamine resin and epoxy resin are preferable in terms of excellent curability.

The blending amount of the cross-linking agent in the curable resin composition is preferably 0.1 to 70% by weight, more preferably 5 to 55% by weight. The amount of the cross-linking agent blended is preferably 10 to 1000 parts by weight, more preferably 20 to 1000 parts by weight, based on 100 parts by weight of the curable resin. If it is less than 10 parts by weight, the antibacterial property of the coating film may be insufficient, and if it exceeds 1000 parts by weight, the drying property may be insufficient.

The curable resin composition includes an epoxy compound, a halohydrin compound, an amine compound, an aziridine compound, an isocyanate compound, an oxazoline compound and the like, in addition to the cross-linking agent represented by the general formula (1), as long as the effects of the present invention are not impaired. It may contain a cross-linking agent capable of reacting with the curable resin of.

The curable resin composition may contain a commonly available surfactant, solvent, antioxidant, catalyst, antifoaming agent, rheology control agent, adhesion imparting agent, thickener, neutralizing agent and the like. ..

The surface active agent has a leveling function by adjusting the surface, and is not particularly limited. For example, a polyether-modified polydimethylsiloxane, a polyether-modified siloxane, a polyether ester-modified hydroxyl group-containing polydimethylsiloxane, or a polyether-modified agent. Siloxane-based compounds such as acrylic group-containing polydimethylsiloxane, polyester-modified acrylic group-containing polydimethylsiloxane, perfluoropolydimethylsiloxane, perfluoropolyether-modified polydimethylsiloxane, and perfluoropolyester-modified polydimethylsiloxane; perfluoroalkylcarboxylic acid, etc. Fluorine compounds; polyether compounds such as polyoxyalkylene alkyl ethers and polyoxyethylene alkyl phenyl ethers; carboxylic acids such as coconut oil fatty acid amine salts; phosphoric acid esters, alkyl ether sulfates, sorbitan fatty acid esters, sulfonic acid esters , Ether compounds such as succinate; sulfonate compounds such as alkylaryl sulfonic acid amine salt and dioctyl sulfosuccinate; phosphate compounds such as sodium lauryl phosphate; amide compounds such as coconut oil fatty acid ethanol amide; acrylic Examples include system compounds. These surfactants may be used alone or in combination of two or more.

The content of the surfactant is preferably 0.001 to 10 parts by weight, more preferably 0.01 to 5 parts by weight, based on 100 parts by weight of the curable resin. If it is less than 0.001 part by weight, the leveling property may be insufficient, and if it exceeds 10 parts by weight, the adhesion of the coating film may be insufficient.

As the solvent, either an aqueous solvent or an organic solvent solvent can be preferably used. For example, an aromatic hydrocarbon solvent such as toluene, ethylbenzene, trimethylbenzene and xylene, and an aliphatic hydrocarbon solvent such as pentane, hexane and cyclohexane can be used. , Aketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, alcohol solvents such as methanol, ethanol, isopropanol, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl diglycol , Glycol ether solvents such as ethyl diglycol, butyl diglycol and propylene glycol monomethyl ether, ester solvents such as ethyl acetate, butyl acetate and propylene glycol monomethyl ether acetate, water and the like. Examples of commercially available products that can be used as an aromatic hydrocarbon solvent include Solbesso 100, Solbesso 150, and Solbesso 200. These solvents may be used alone or in combination of two or more.

The content of the solvent depends on the type of resin, the coating method, and the film thickness of the cured coating film, but is preferably 10 to 1000 parts by weight, more preferably 20 to 400 parts by weight, based on 100 parts by weight of the curable resin. .. If it is less than 10 parts by weight, the viscosity may be high and uniform coating may not be possible, and if it exceeds 1000 parts by weight, a desired film thickness may not be obtained, which is not preferable from the viewpoint of economy and VOC reduction.

The solid content concentration of the curable resin composition is not particularly limited, but is preferably 10 to 80% by weight, more preferably 15 to 50% by weight. If it exceeds 80% by weight, the viscosity may be high and uniform coating may not be possible, and if it is less than 10% by weight, a desired film thickness may not be obtained, which is not preferable from the viewpoint of economy and VOC reduction.

(4) Applications of curable resin composition The curable resin composition can be used for applications such as coating agents and paints.

When the curable resin composition is used as a coating agent or a paint, as a method of forming a coating film on the base material, the curable resin composition is applied to at least one surface of the base material and then heated and cured. There is a method of making it.

The base material is not particularly limited to synthetic resin, metal, glass and the like, but for example, polyester such as polyethylene terephthalate and polyethylene naphthalate, polyolefin such as polyethylene, polypropylene and polymethylpentene, polyamide such as nylon 6 and nylon 66, and polycarbonate. , Polyvinyl acetate, polyimide, ABS resin, steel, aluminum, glass and the like.

The method for applying the curable resin composition onto the substrate is not particularly limited, but for example, a bar coating method, a spin coating method, a spray coating method, a dip coating method, a nozzle coating method, a gravure coating method, and a reverse roll coating method. Method, die coat method, air doctor coat method, blade coat method, rod coat method, curtain coat method, knife coat method, transferor coat method, squeeze coat method, impregnation coat method, kiss coat method, calendar coat method, extrusion coat method, etc. Can be mentioned.

The heating temperature at the time of heating after applying the curable resin composition to the base material is preferably 60 to 250 ° C, more preferably 60 to 200 ° C. If the heating temperature is less than 60 ° C., curing may be poor, and if it exceeds 250 ° C., the shape of the base material may be impaired depending on the material of the resin base material. The heating time is preferably 5 to 300 seconds, more preferably 20 to 120 seconds. If the heating time is less than 5 seconds, curing may be poor, and if it exceeds 300 seconds, the shape of the base material may be impaired depending on the material of the resin base material, and the time required for the process is long. Therefore, it is not preferable from the viewpoint of productivity.

The thickness of the coating film after curing is not particularly limited, but is preferably 0.1 to 30 μm, and more preferably 0.3 to 20 μm. If the thickness is less than 0.1 μm, the smoothness of the coating film may be insufficient, and if it exceeds 30 μm, the adhesion may be insufficient due to an increase in internal stress.

(Example 1) Production of cross-linking agent 200 g (2.2 mol) of glycerin and 0.3 g of boron trifluoride ether complex as a catalyst were charged in a 1000 mL volume separable flask, heated and stirred, and 442 g of epichlorohydrin (442 g). 4.8 mol) was added dropwise and stirred. Further, 69 g (0.8 mol) of a 50% aqueous solution of dimethylamine was added, and the mixture was stirred. Then, 62 g of 48.5% liquid caustic soda was added dropwise, followed by aging for 12 hours. The obtained reaction product was dissolved in methanol and then filtered. 168 g of 48.5% liquid caustic soda was added to the filtrate, and the mixture was stirred and filtered. After distilling off the methanol in the filtrate, distilled water was added to dissolve the concentrated residue, 20 g of 98% sulfuric acid was added, and the mixture was stirred for 12 hours.

In the general formula (1), A is a glycerin residue, B is a substituent represented by the general formula (2) or the general formula (3), R ¹ is a methyl group, and R ² is a hydrogen atom or a hydrogen atom. A methyl group, X is a counter ion of a quaternary ammonium group and represents a chloride ion, a sulfate ion, or a hydroxide ion, respectively, m and n are 0 or 1, respectively, and m + n is 1. The cross-linking agent of the present invention in which l is 1 to 4 was obtained.

(Example 2 and Comparative Example 1) Production of coating composition The melamine resin, the cross-linking agent synthesized in Example 1 or the comparative cross-linking agent containing no alcohol skeleton, the surfactant, and the solvent are arranged in the weight ratio shown in Table 1 below. Mixing gave the coating compositions of Example 2 and Comparative Example 1.
The following components were used as each component.
Melamine resin: Cymel 327 (Imino-based methylated melamine resin, manufactured by Daicel Ornex Co., Ltd.)
Comparative cross-linking agent: Weistex H90 (dimethylamine / epichlorohydrin polycondensate, manufactured by Nagase ChemteX Corporation)
Solvent: Solmix AP-7 (alcohol-based solvent, manufactured by Japan Alcohol Trading Co., Ltd.)
Surfactant: Softanol 90 (polyoxyethylene alkyl ether, manufactured by Nippon Shokubai Co., Ltd.)

(Measurement Example) Preparation of Test Piece and Evaluation of Physical Properties The coating compositions of Example 2 and Comparative Example 1 were applied onto a substrate using a bar coater (No. 2). A polyester (PET) film (E5100 (film thickness 50 μm) manufactured by Toyobo Co., Ltd.) was used as a base material. The applied base material was placed in a hot air dryer at 170 ° C. and dried for 1 minute. After drying, the base material was allowed to stand at room temperature, and the base material was cooled to room temperature and used as a test piece. Moreover, the antibacterial property of the base material itself to which the coating composition was not applied was evaluated (Comparative Example 2). Using the obtained test piece, the physical properties were evaluated by the method described later. The results are shown in Table 1.

<Evaluation method of physical properties of cured coating film>
1. 1. Coating stability The coating composition was stirred with a stirrer, allowed to stand for 1 minute, and then the appearance was confirmed and evaluated in two stages according to the following criteria.
◯: No precipitation ×: With precipitation

2. 2. Adhesion was confirmed by a grid test (former JIS K5400) using a test piece immediately after preparation, and evaluated in two stages according to the following criteria.
◯: No peeling (100/100)
×: With peeling

3. 3. An antibacterial property test (JIS Z 2801) was conducted using a test piece immediately after preparation. The test target bacterium was Escherichia coli. It was evaluated on a two-point scale according to the following criteria.
◯: Antibacterial activity value 2.0 or more ×: Antibacterial activity value less than 2.0

The coating composition of Example 2 obtained by using the cross-linking agent of Example 1 has excellent liquid coating stability, the coating film has excellent adhesion to the substrate, and has sufficient antibacterial properties. It was.

The coating composition of Comparative Example 1 obtained by using the comparative cross-linking agent according to the prior art had precipitation and was inferior in liquid stability. It is presumed that this is because the cross-linking agent does not contain a polyhydric alcohol skeleton, so that agglutination with the curable resin is likely to occur. Since the coating composition of Comparative Example 1 was precipitated, a good coating film could not be formed, and the adhesion and antibacterial property of the coating film to the substrate could not be measured. The base material of Comparative Example 2 to which the coating composition was not applied did not have antibacterial properties.

Claims (5)

The following general formula (1):

(In the general formula (1), A represents a (m + n + 2) -valent polyhydric alcohol residue having 1 to 6 carbon atoms.
B is the following general formula (2):

Or the following general formula (3):

Represents a substituent represented by
R ¹ represents a hydrocarbon group having 1 to 6 carbon atoms.
R ² represents a hydrogen atom or a hydrocarbon group having 1 to 4 carbon atoms.
X is a counterion of a quaternary ammonium group and represents a chloride ion, a bromide ion, a sulfate ion, a nitrate ion, a phosphate ion, or a hydroxide ion.
m and n each independently represent an integer of 0 to 4, and m and n bonded to the same substituent A satisfy 0 ≦ m + n ≦ 4.
l is 1 to 6
k is an integer greater than or equal to 1. )
A cross-linking agent containing a compound represented by. The cross-linking agent according to claim 1, wherein R ¹ is a methyl group. The cross-linking agent according to claim 1 or 2, wherein m and n satisfy 0 ≦ m + n ≦ 1. A curable resin composition containing a curable resin and the cross-linking agent according to any one of claims 1 to 3. The following steps 1-3:
(Step 1) The following general formula (4):
A- (OH) _{m + n + 2} (4)
(In the general formula (4), A represents a (m + n + 2) -valent polyhydric alcohol residue having 1 to 6 carbon atoms, and m and n independently represent an integer of 0 to 4, and 0 ≦ m + n ≦ 4. Satisfy.)
The step of reacting a (m + n + 2) -valent polyhydric alcohol represented by (m + n + 2) with epihalohydrin,
(Step 2) The reaction product obtained in Step 1 and the following general formula (5):
R ¹ ₂ NH (5)
(In the general formula (5), R ¹ represents a hydrocarbon group having 1 to 6 carbon atoms.)
The process of reacting with the secondary amine represented by, and
(Step 3) Claim 1 includes a step of converting a halogen atom in the reaction product obtained in step 2 into -OR ² groups (R ² represents a hydrogen atom or a hydrocarbon group having 1 to 4 carbon atoms). The method for producing a cross-linking agent according to any one of 3 to 3.