JP2007302785A - Curing agent for resins and curable resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a curing agent which can form coating films having excellent solvent resistance, when used for resins, preferably water-soluble acrylic resins and/or epoxy resins, and to provide a curable resin composition containing the same. <P>SOLUTION: This curing agent is characterized by containing an aluminum chelate obtained by reacting (1) at least one aluminum alkoxide with (2) at least one alkoxy group or hydroxyl group-containing β-ketoester represented by the general formula (L1) [R<SP>1</SP>is a 1 to 3C alkyl or an aryl; R<SP>2</SP>is H, a 1 to 8C alkyl, an alkenyl, or benzyl; A is 2 to 8C alkylene; (n) is an integer of 1 to 4]. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an aluminum chelate suitable for use as a curing agent for acrylic resins and epoxy resins used in paints, inks, adhesives, pressure-sensitive adhesives, electrical insulating materials and the like. Furthermore, the present invention relates to a curable resin composition containing the aluminum chelate and at least one selected from a water-soluble acrylic resin and a water-soluble epoxy resin.

  Japanese Patent Publication No. 48-17859 (Patent Document 1) discloses a one-component room-temperature-curing coating containing a linear copolymer having a carboxyl group in the molecule, an aluminum complex compound, a ketoenol-type tautomeric compound and a solvent. A composition is disclosed. JP-A-4-13787 (Patent Document 2) discloses a coating resin composition containing a bisphenol-type epoxy resin, an aluminum alcoholate and a novolac-type phenol resin having an epoxy equivalent of 180 to 4000. However, depending on the type of resin, particularly in the case of a water-soluble resin, the film obtained by applying a curable resin composition containing an aluminum chelate has poor solvent resistance and insufficient strength. was there.

JP-A-2004-339366 (Patent Document 3) discloses a resin curing agent containing an aluminum chelate obtained by reacting an aluminum alkoxide and β-ketoamide. Although improvement in curing performance such as solvent resistance is seen, there is a problem in operability such as difficulty in adding to the resin to be cured because the curing agent is solid.
Japanese Patent Publication No. 48-17859 JP-A-4-13787 JP 2004-339366 A

  The present invention provides a curing agent having excellent solvent resistance and good operability when added as a curing agent to a resin, preferably a water-soluble acrylic resin and / or epoxy resin, and a operability thereof. It is intended to provide a curable resin composition containing

  As a result of intensive studies to solve the above problems, the present inventor has used an aluminum chelate having a specific structure as a ligand as a curing agent for a resin, preferably a water-soluble acrylic resin and / or an epoxy resin. When used, it was found that a film excellent in solvent resistance was formed, and the present invention was completed based on this finding.

〔但し、一般式(L1)中、Ｒ^１は、１〜３個の炭素原子を有するアルキル基、又はアリール基を表し、Ｒ^２は、水素原子、１〜８個の炭素原子を有するアルキル基又はアルケニル基、或はベンジル基を表し、Aは２〜８個の炭素原子を有するアルキレン基を表し、nは１〜４の整数を表す〕
を反応させて得られるアルミニウムキレートを含有することを特徴とするものである。
また、本発明の樹脂用硬化剤（Ｃ２）は、
（１）少なくとも１種のアルミニウムアルコキシド
（２）下記一般式（Ｌ１）によって表わされ、かつアルコキシ基又はヒドロキシル基を有する少なくとも１種のβ−ケトエステル：

〔但し、一般式(L1)中、Ｒ^１は、１〜３個の炭素原子を有するアルキル基、又はアリール基を表し、Ｒ^２は、水素原子、１〜８個の炭素原子を有するアルキル基又はアルケニル基、或はベンジル基を表し、Aは２〜８個の炭素原子を有するアルキレン基を表し、nは１〜４の整数を表す〕
及び
（３）前記一般式(L1)により表されるβ−ケトエステルとは異種の、少なくとも１種のケトエノール型互変異性化合物との反応により得られるアルミニウムキレートを含有することを特徴とするものである。
本発明の樹脂用硬化剤（Ｃ２）において、前記ケトエノール型互変異性化合物（３）が、下記一般式（Ｌ２）で表わされるβ−ケトエステル、下記一般式（Ｌ３）で表わされるβ−ケトアミド、及び下記一般式（Ｌ４）で表わされるβ−ジケトン：

〔但し、一般式（Ｌ２）中、Ｒ^３は、１〜３個の炭素原子を有するアルキル基、或はアリール基を表し、Ｒ^４は、１〜１８個の炭素原子を有するアルキル基又はアルケニル基、或はベンジル基を表し、一般式（Ｌ3）中、Ｒ^５は、１〜４個の炭素原子を有するアルキル基を表し、Ｒ^６及びＲ^７は、それぞれ互いに独立に、１〜８個の炭素原子を有する未置換の、又は置換されたアルキル基、或は未置換の、又は置換されているアリール基を表し、一般式（Ｌ4）中、Ｒ^８及びＲ^９は、それぞれ互いに独立に、１〜８個の炭素原子を有するアルキル基、或はアリール基を表す〕
から選ばれることが好ましい。
本発明の硬化性樹脂組成物は、前記本発明の上記樹脂用硬化剤（Ｃ１）又は（Ｃ２）を含む硬化剤成分と、水溶性アクリル樹脂及びエポキシ樹脂から選ばれた少なくとも一種を含有する樹脂成分とを含むことを特徴とするものである。
本発明の硬化性樹脂組成物は、さらにポリエポキシ化合物を含むエポキシ成分を含有することが好ましい。 That is, the curing agent for resin (C1) of the present invention is:
(1) at least one aluminum alkoxide;
(2) At least one β-ketoester represented by the following general formula (L1) and having an alkoxy group or a hydroxyl group:

[In the general formula (L1), R ¹ represents an alkyl group having 1 to 3 carbon atoms or an aryl group, and R ² represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. Or an alkenyl group or a benzyl group, A represents an alkylene group having 2 to 8 carbon atoms, and n represents an integer of 1 to 4]
It contains the aluminum chelate obtained by making it react.
Moreover, the curing agent for resin (C2) of the present invention comprises:
(1) At least one kind of aluminum alkoxide (2) At least one kind of β-ketoester represented by the following general formula (L1) and having an alkoxy group or a hydroxyl group:

[In the general formula (L1), R ¹ represents an alkyl group having 1 to 3 carbon atoms or an aryl group, and R ² represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. Or an alkenyl group or a benzyl group, A represents an alkylene group having 2 to 8 carbon atoms, and n represents an integer of 1 to 4]
And (3) an aluminum chelate obtained by reaction with at least one ketoenol-type tautomeric compound different from the β-ketoester represented by the general formula (L1). is there.
In the curing agent for resin (C2) of the present invention, the keto enol tautomer compound (3) is a β-ketoester represented by the following general formula (L2), a β-ketoamide represented by the following general formula (L3), And a β-diketone represented by the following general formula (L4):

[In the general formula (L2), R ³ represents an alkyl group having 1 to 3 carbon atoms or an aryl group, and R ⁴ represents an alkyl group or alkenyl having 1 to 18 carbon atoms. Represents a group or a benzyl group, and in general formula (L3), R ⁵ represents an alkyl group having 1 to 4 carbon atoms, and R ⁶ and R ⁷ are each independently 1 to 8 Represents an unsubstituted or substituted alkyl group having the following carbon atoms, or an unsubstituted or substituted aryl group, and in general formula (L4), R ⁸ and R ⁹ are each independently Represents an alkyl group having 1 to 8 carbon atoms or an aryl group]
Is preferably selected from.
The curable resin composition of the present invention is a resin containing a curing agent component containing the above-mentioned curing agent for resin (C1) or (C2) of the present invention, and at least one selected from a water-soluble acrylic resin and an epoxy resin. And a component.
The curable resin composition of the present invention preferably further contains an epoxy component including a polyepoxy compound.

  The resin curing agent (C1) or (C2) of the present invention has a high fluidity at room temperature because the aluminum chelate contained therein contains a β-ketoester of the general formula (L1) as a ligand. The curing agents (C1) and (C2) have good operability and are used as a curing agent for a curable resin, preferably a water-soluble acrylic resin and / or an epoxy resin, to form a cured film with high solvent resistance. Can do.

  The resin curing agent (C1) of the present invention contains an aluminum chelate obtained as a reaction product of an aluminum alkoxide (1) and a β-ketoester (2) represented by the general formula (L1), The curing agent for resin (C2) of the present invention is an aluminum alkoxide (1), a β-ketoester (2) of the general formula (L1), and a ketoenol type different from the β-ketoester (2) of the formula (L1). It contains an aluminum chelate obtained by reacting the tautomeric compound (3).

In the curing agent (C1), it is preferable that three molecules of β-ketoester (2) are coordinated to one atom of aluminum. In the curing agent (C2), a general formula ( It is preferable that a total of 3 molecules of the β-ketoester (2) of L1) and a ketoenol-type tautomeric compound different from that are coordinate-bonded. In order to obtain an aluminum chelate having a relatively low molecular weight and fluidity at room temperature, the curing agent (C2) is more preferable than the curing agent (C1).
The aluminum alkoxide (1) used for the preparation of the curing agent (C1) or (C2) is not particularly limited, but an alkoxide having an alkoxy group containing 2 to 5 carbon atoms is preferably used. Examples thereof include triethoxide and aluminum isopropoxide.

  The β-ketoester (2) represented by the general formula (L1) is, for example, 2-methoxyethyl acetoacetate, 2-ethoxyethyl acetoacetate, 2-isopropoxyethyl acetoacetate, 2-butoxyethyl acetoacetate, acetoacetate 3 -Ethoxy-1-propyl, 3-methoxy-1-butyl acetoacetate, 2-hydroxyethyl acetoacetate, 3-oxopentanoic acid (2-ethoxyethyl), 2- (2-methoxyethoxy) ethyl acetoacetate, and acetoacetate Examples include 2- (2-hydroxyethoxy) ethyl acetate and the like. Among the β-ketoester compounds of the general formula (L1), compounds of the general formula (L1) where n = 1, such as 2-methoxyethyl acetoacetate, 2-butoxyethyl acetoacetate, 3-ethoxy-1-propyl acetoacetate Etc. are preferably used. More preferably, it is selected from 2-methoxyethyl acetoacetate, 2-ethoxyethyl acetoacetate and 2-isopropoxyethyl acetoacetate.

The ketoenol tautomeric compound (3) which is different from the β-ketoester (2) represented by the general formula (L1) includes β-ketoester of the general formula (L2), β-ketoamide of the general formula (L3) and general Selected from the β-diketone of formula (L4).
The β-ketoester compound represented by the general formula (L2) is, for example, methyl acetoacetate, ethyl acetoacetate, octyl acetoacetate, oleyl acetoacetate, lauryl acetoacetate, stearyl acetoacetate, benzyl acetoacetate, methyl 3-oxopentanoate , Octyl 3-oxopentanoate and the like, preferably selected from methyl acetoacetate and ethyl acetoacetate.

  Examples of the β-ketoamide compound represented by the general formula (L3) include acetoacetamide, N-methylacetoacetamide, N, N-dimethylacetoacetamide, N, N-diethylacetoacetamide, N- (2-hydroxy Ethyl) acetoacetamide, N, N-bis (2-hydroxyethyl) acetoacetamide, N- (2- (2-hydroxyethoxy) ethyl) acetoacetamide, acetoacetate anilide, N- (2-methylphenyl) Including acetoacetamide, N- (4-methoxyphenyl) acetoacetamide, N- (4-chlorophenyl) acetoacetamide, 3-oxopentanoic acid amide, etc., preferably N, N-dimethylacetoacetamide N, N-diethylacetoacetamide and N- (2- (2-hydroxyethoxy) ethyl) acetoacetate Selected from the group consisting of de.

  The β-diketone compound represented by the general formula (L4) includes, for example, acetylacetone, 1-benzoylacetone and dibenzoylmethane, and is preferably acetylacetone.

The aluminum chelate of the present invention can be produced, for example, by the following method.
That is, aluminum alkoxide is dissolved in an appropriate solvent (for example, 2-propanol or ethanol), and a predetermined molar amount of the β-ketoester compound of the general formula (L1) or the compound of the general formula (L1) is added to this solution. A β-ketoester compound, one or more selected from β-ketoester (general formula (L2)), β-ketoamide (general formula (L3)), and β-diketone (general formula (L4)) are dropped as they are. Alternatively, as a solution obtained by dissolving these in an appropriate solvent (for example, 2-propanol, ethanol, etc.), this is dropped, and this mixed solution is heated to produce an aluminum chelate. After completion of the reaction, the target aluminum chelate compound can be produced by distilling off the solvent from the reaction solution.

  Examples of the aluminum chelate for the curing agent (C1) or (C2) of the present invention obtained as described above include, for example, tris ((2-ethoxyethyl) acetoacetate) aluminum (III), (ethylacetoacetate) bis (( 2-methoxyethyl) acetoacetato) aluminum (III), (N, N-diethylacetoacetamide) bis ((2-methoxyethyl) acetoacetate) aluminum (III), bis (N, N-dimethylacetoacetamide) ((2-ethoxyethyl) acetoacetato) aluminum (III), bis ((2-ethoxyethyl) acetoacetato) (acetylacetonato) aluminum (III), bis ((2-methoxyethyl) acetoacetato) (acetylacetonato) aluminum (III), tris ((2-hydroxyethyl) ace Acetato) aluminum (III), ((2-ethoxyethyl) and Asetoasetato) bis (N- (2- (2- hydroxyethoxy) ethyl) acetoacetate Tamil Dato) aluminum (III) are included.

The resin used by blending the curing agent of the present invention is not particularly limited as long as it can be cured by the curing agent of the present invention, but is generally selected from an acrylic resin and an epoxy resin. preferable.
The monomer for acrylic resin used in the present invention includes (a) a (meth) acrylic acid monomer having one or more active hydrogens in one molecule, that is, acrylic acid and methacrylic acid; (b) other ethylenic monomers. Saturated carboxylic acids such as crotonic acid, itaconic acid, fumaric acid, maleic anhydride, etc .; (c) (meth) acrylic acid esters having hydroxyl groups, such as 2-hydroxyethyl acrylate, 2-hydroxybutyl acrylate, And (meth) acrylic acid monoglyceryl ester, etc .; (d) (meth) acrylic acid ester having an amino group, such as dimethylaminoethyl acrylate, diethylaminoethyl methacrylate, etc .; (e) oxygen atom-containing saturated 3-5 (Meth) acrylic acid esters having a member ring group, such as glycidyl acrylate, and Tetrahydrofurfuryl tacrylate is used, and at least one polymer and copolymer selected from these monomer groups, and a copolymer of the monomer and a different monomer copolymerizable therewith, Used as an acrylic resin for the present invention. Examples of the different monomers include (a) acrylic acid esters such as methyl acrylate, ethyl acrylate, butyl acrylate, and 2-ethylhexyl acrylate; and (b) methacrylic acid esters such as methyl methacrylate and methacrylic acid. Ethyl, lauryl methacrylate, glycidyl methacrylate, and the like; (c) unsaturated carboxylic acid amides, such as acrylic acid amides and N-methylol acrylic acid amides; and (d) other polymerizable monomers, such as acrylonitrile, vinyl acetate, and Styrene or the like is used.

As the epoxy resin for the present invention, glycidyl ether type epoxy resin (bisphenol A type, bisphenol F type, phenol novolac type, etc.), cyclic aliphatic epoxy resin (alicyclic diepoxy acetal, alicyclic diepoxy adipate, etc.), Glycidyl ester type epoxy resins (phthalic acid diglycidyl ester, tetrahydrophthalic acid diglycidyl ester, etc.), glycidyl amine type epoxy resins (tetraglycidyl diaminodiphenylmethane, triglycidyl p-aminophenol, etc.), heterocyclic epoxy resins (diglycidyl hydantoin) And hydantoin type epoxy resins such as triglycidyl isocyanurate) and resins obtained by modifying these epoxy resins with amines or polyamides.
Moreover, the epoxy component further contained in the curable resin composition of the present invention, if necessary, includes one or more polyepoxy compounds, for example, polyglycidyl ether polyols such as glycerin polyglycidyl ether and diglycerin polyglycidyl ether, low A bisphenol type epoxy resin having a degree of polymerization is included.

As described above, the curable resin composition of the present invention preferably contains at least one resin selected from acrylic resins and epoxy resins and the aluminum chelate-containing curing agent of the present invention.
When an acrylic resin, particularly a water-soluble acrylic resin is used, it is preferable that an epoxy component containing the polyepoxy compound, particularly a polyglycidyl ether polyol soluble in water, is used in combination. When an epoxy component such as polyglycidyl ether polyol is not contained, the pot life may be short and the curing process may be difficult.

  Further, the curable resin composition of the present invention contains a curing agent different from the aluminum chelate of the present invention, and if necessary, for example, amino resins such as lower amines and melamine resins, phenol resins, isocyanates, and acid anhydrides. One or more kinds, additives such as pigments, pigment dispersants, antioxidants, leveling agents, viscoelasticity modifiers, and dilution solvents may also be contained.

  In the case of a curable resin composition containing an acrylic resin, solvent: 10 to 90% by weight, acrylic resin-containing resin component: 10 to 90% by weight, polyepoxy compound-containing epoxy component: 0 to 50% by weight, Aluminum chelate-containing curing agent component: It is preferably blended in the range of 0.01 to 20% by weight.

  In the case of a curable resin composition containing an epoxy resin, solvent: 10 to 90% by weight, epoxy resin-containing resin agent component: 10 to 90% by weight, the aforementioned aluminum chelate-containing curing agent component: 0.01 to 20% by weight It is preferable to mix in the range of%.

  Depending on the functional groups of the resin and the presence or absence of stabilizers, if the content of the curing agent component is less than 0.01% by weight, the curability is insufficient and only a film with low performance such as solvent resistance can be obtained. Therefore, it is not preferred, and if it exceeds 20% by weight, the pot life is shortened and the curing treatment becomes difficult, which is not preferred.

The curable resin composition of the present invention can be obtained by a general method of mixing each component with a sand mill, a bead mill, a paint shaker or the like.
The curable resin composition of the present invention can be used for paints, inks, adhesives, pressure-sensitive adhesives, electrical insulating materials and the like.

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.
Production Example 1

In a 300 ml four-necked flask is charged 7.0 g (0.034 mol) aluminum triisopropoxide and 63 g 2-propanol, and the mixture is stirred at 55-65 ° C. with 2-ethoxyethyl acetoacetate 17 .9 g (0.103 mol) was added dropwise. After completion of the dropwise addition, the obtained reaction mixture was reacted at 83 ° C. under reflux for 45 minutes, and then the solvent (2-propanol) was removed to give a light brown viscous liquid tris ((2-ethoxyethyl) acetoacetate. ) 19.0 g of aluminum (III) (hereinafter referred to as Al (EOEAAA) ₃ ) was obtained.
Aluminum content: 4.89% (theoretical value: 4.94%)
IR spectrum (cm ⁻¹ ); 2974, 2928, 2871 (C—H stretching vibration), 1612, 1519 (C═O stretching vibration), 1418, 1388 (C—H bending vibration), 1306, 1173 (C—) O stretching vibration), 1126, 1064 (C—O—C stretching vibration), 975, 622, 485 (Al—O stretching vibration)

Production Example 2
In a 500 ml four-necked flask, 60.4 g (0.296 mol) of aluminum triisopropoxide and 140 g of 2-propanol were charged, and this mixture was stirred at 55-65 ° C. with 38.5 g (0 .296 mol) was added dropwise. After completion of the dropwise addition, the resulting reaction mixture was reacted at 83 ° C. under reflux for 30 minutes. The obtained reaction mixture was once cooled to 50 ° C., and 94.7 g (0.591 mol) of 2-methoxyethyl acetoacetate was added dropwise thereto. The obtained reaction mixture was reacted at 83 ° C. under reflux for 1 hour, and then the solvent (2-propanol) was removed to give a brown viscous liquid (ethylacetoacetato) bis ((2-methoxy). ethyl) Asetoasetato) aluminum (III) (hereinafter, to obtain a Al _(EAA) (MOEAA) ₂ referred to) 140.4 g.
Aluminum content: 5.71% (theoretical 5.69%)
IR spectrum (cm ⁻¹ ); 2982, 2931, 2892 (C—H stretching vibration), 1609, 1523 (C═O stretching vibration), 1420, 1374 (C—H bending vibration), 1294, 1176 (C—) O stretching vibration), 1130, 1065 (C—O—C stretching vibration), 978, 629, 497 (Al—O stretching vibration)

Production Example 3
In a 300 ml four-necked flask, 7.0 g (0.034 mol) of aluminum triisopropoxide and 63 g of 2-propanol were charged, and the mixture was stirred at 55 to 65 ° C. with N, N-diethylacetoacetate. 5.4 g (0.034 mol) of amide was added dropwise. After completion of the dropwise addition, the resulting reaction mixture was reacted at 83 ° C. under reflux for 30 minutes. The obtained reaction mixture was once cooled to 60 ° C., and 11.0 g (0.069 mol) of 2-methoxyethyl acetoacetate was added dropwise thereto. The obtained reaction mixture was reacted at 83 ° C. under reflux for 1 hour, and then the solvent (2-propanol) was removed to give a brown viscous liquid (N, N-diethylacetoacetamidate) bis. 17.4 g of ((2-methoxyethyl) acetoacetato) aluminum (III) (hereinafter referred to as Al (DEAM) (MOEAA) ₂ ) was obtained.
Aluminum content: 5.32% (theoretical value 5.38%)
IR spectrum (cm ⁻¹ ); 2976, 2931, 2891 (C—H stretching vibration), 1612, 1580, 1523 (C═O stretching vibration), 1421, 1376 (C—H bending vibration), 1294, 1173 ( C-O stretching vibration), 1130, 1067 (C-O-C stretching vibration), 975, 628, 488 (Al-O stretching vibration)

Production Example 4
In a 300 ml four-necked flask, 15.0 g (0.073 mol) of aluminum triisopropoxide and 135 g of 2-propanol were charged, and this mixture was stirred at 55 to 65 ° C. with N, N-diethylacetate. Acetic amide 23.1 g (0.147 mol) was added dropwise. After completion of the dropwise addition, the resulting reaction mixture was reacted at 83 ° C. under reflux for 30 minutes. The obtained reaction mixture was once cooled to 60 ° C., and 11.8 g (0.073 mol) of 2-methoxyethyl acetoacetate was added dropwise thereto. The obtained reaction mixture was reacted at 83 ° C. under reflux for 1 hour, and then the solvent (2-propanol) was removed to give a brown viscous liquid bis (N, N-diethylacetoacetamidate). ((2-methoxyethyl) Asetoasetato) aluminum (III) (hereinafter referred to as _{Al (DEAM) 2 (MOEAA)} ) was obtained 37.6 g.
Aluminum content: 5.36% (theoretical value: 5.41%)
IR spectrum (cm ⁻¹ ); 2975, 2932, 2875 (C—H stretching vibration), 1577, 1524 (C═O stretching vibration), 1421, 1377 (C—H bending vibration), 1287, 1169 (C—) O stretching vibration), 1130, 1067 (C—O—C stretching vibration), 974, 684 (Al—O stretching vibration)

Production Example 5
In a 300 ml four-necked flask, 15.0 g (0.073 mol) of aluminum triisopropoxide and 60 g of 2-propanol were charged, and this mixture was stirred at 55 to 65 ° C., and this was added to 2-ethoxyethyl acetoacetate. 25.6 g (0.147 mol) was added dropwise. After completion of the dropwise addition, the resulting reaction mixture was reacted at 83 ° C. under reflux for 30 minutes. The obtained reaction mixture was once cooled to 60 ° C., and 7.4 g (0.073 mol) of acetylacetone was added dropwise thereto. The obtained reaction mixture was reacted at 83 ° C. under reflux for 1 hour, then the solvent (2-propanol) was removed, and a yellow viscous liquid bis ((2-ethoxyethyl) acetoacetate) (acetylacetonate) was obtained. ) 35.0 g of aluminum (III) (hereinafter referred to as Al (EOEAAA) ₂ (acac)) was obtained.
Aluminum content: 5.66% (theoretical value 5.71%)
IR spectrum (cm ⁻¹ ); 2975, 2930, 2870 (C—H stretching vibration), 1607, 1525 (C═O stretching vibration), 1420, 1391 (C—H bending vibration), 1292, 1174 (C—) O stretching vibration), 1125, 1067 (C—O—C stretching vibration), 978, 687, 495 (Al—O stretching vibration)

Production Example 6
In a 300 ml four-necked flask, 7.5 g (0.037 mol) of aluminum triisopropoxide and 68 g of 2-propanol were charged, and the mixture was stirred at 55 to 65 ° C., and then 2- (2- 16.0 g (0.073 mol) of ethoxyethoxy) ethyl was added dropwise. After completion of the dropwise addition, the resulting reaction mixture was reacted at 83 ° C. under reflux for 30 minutes. The obtained reaction mixture was once cooled to 60 ° C., and 3.7 g (0.037 mol) of acetylacetone was added dropwise thereto. The obtained reaction mixture was reacted at 83 ° C. under reflux for 1 hour, and then the solvent (2-propanol) was removed to give a yellow viscous liquid bis ((2- (2-ethoxyethoxy) ethyl). 20.7 g of acetoacetato) (acetylacetonato) aluminum (III) (hereinafter referred to as Al (EEOEAA) ₂ (acac)) was obtained.
Aluminum content: 4.79% (theoretical value: 4.81%)
IR spectrum ^{(cm -1); 2974,2925,2870 (C} -H stretching vibration), 1606,1526 (C = O stretching vibration), 1420,1395 (C-H bending vibration), 1295,1175 (C- O stretching vibration), 1116, 1068 (C—O—C stretching vibration), 980, 688, 495 (Al—O stretching vibration)

  Table 1 shows the types and analysis results of the aluminum chelates produced in Production Examples 1 to 6.

  In each of the following examples and comparative examples, a curable resin composition containing the aluminum chelate shown in Table 1 was prepared, and this composition was subjected to a film formation test under predetermined curing conditions to prepare a film. The curing performance was measured. The curing conditions will be described later.

Examples 1-6 and Comparative Examples 1-4
In each of Examples 1 to 6 and Comparative Examples 1 to 4, a water-soluble acrylic resin (trademark: Watersol S-744; resin solid content 40%; ammonia neutralized type; large) according to the composition described in Tables 2 and 3 An aluminum chelate was added to Nippon Ink Chemical Co., Ltd. (hereinafter referred to as S-744), and mixed by stirring to prepare a curable resin composition.

Examples 7-11 and Comparative Examples 5-8
In each of Examples 7 to 11 and Comparative Examples 5 to 8, a water-soluble acrylic resin (trademark: Jonkrill 61J; resin solid content 30.5%; acid value 195; molecular weight 12) according to the composition described in Tables 4 and 5 000; manufactured by Johnson Polymer Co., Ltd .; hereinafter referred to as JC61J), an aluminum chelate was added and mixed by stirring to prepare a curable resin composition.

Examples 12-16, Comparative Examples 9-12
In each of Examples 12 to 16 and Comparative Examples 9 to 12, a water-soluble acrylic resin (trademark: PDX-6102B; resin solid content 24.5%; acid value 65; molecular weight 60) according to the composition described in Tables 6 and 7 Aluminum chelates were added to Johnson Polymer Co., Ltd. (hereinafter referred to as PDX) and stirred to prepare a curable resin composition.

Example 17, Comparative Examples 13-14
In each of Example 17 and Comparative Examples 13 to 14, in accordance with the composition described in Table 8, water-soluble acrylic resin S-744, epoxy compound (trademark: Denacol EX-421; solid content 100%; Nagase ChemteX Corporation) Manufactured; hereinafter referred to as EX-421), methanol, and aluminum chelate were mixed by stirring to prepare a curable resin composition.

  The curable resin compositions prepared in each of Examples 1 to 17 and Comparative Examples 1 to 14 were subjected to a cured coating test, and the results are shown in Tables 2 to 8. In addition, the performance evaluation method of the cured film was performed as follows.

Test of cured coating (1) Rubbing test The curable resin composition prepared in each of Examples 1 to 6 and 17 and Comparative Examples 1 to 4 and 13 to 14 was formed on a steel plate to a film thickness of 6 μm using an applicator. The film was applied and cured under the conditions described in Tables 2, 3 and 8 to prepare a film. For the coatings obtained from the curable resin compositions prepared in each of Examples 1 to 6 and Comparative Examples 1 to 4, a methanol / water (3/1; w / w) mixed solution was impregnated. The film was rubbed with absorbent cotton and the maximum number of frictions at which the film was not peeled was measured. The larger this number, the higher the solvent resistance.
The coatings obtained from the curable resin compositions of Example 17 and Comparative Examples 13 to 14 were rubbed with absorbent cotton soaked with methanol, and the maximum number of times the coating could not be peeled was measured.

(2) Gel fraction Each of the curable resin compositions of Examples 7 to 16 and Comparative Examples 5 to 12 was applied on a steel plate to a film thickness of 25 μm using an applicator, and Tables 4 to 7 were applied. A film was prepared by curing under the described conditions.
This coating film was immersed in methanol together with the steel plate and left standing at 25 ° C. After 18 hours, the coated steel plate was taken out and dried. The ratio (%) of each coating weight after solvent immersion to the weight of each coating before solvent immersion was calculated, and the gel fraction of each resin composition coating was represented by the value. The larger this number, the higher the solvent resistance of the coating.

Claims (5)

(1) at least one aluminum alkoxide;
(2) At least one β-ketoester represented by the following general formula (L1) and having an alkoxy group or a hydroxyl group:

[In the general formula (L1), R ¹ represents an alkyl group containing ¹ to 3 carbon atoms or an aryl group, and R ² represents a hydrogen atom, an alkyl group or alkenyl having 1 to 8 carbon atoms. A group or a benzyl group, A represents an alkylene group having 2 to 8 carbon atoms, and n represents an integer of 1 to 4). Curing agent for resin. (1) at least one aluminum alkoxide;
(2) at least one β-ketoester represented by the following general formula (L1) and having an alkoxy group or a hydroxyl group;

[In the general formula (L1), R ¹ represents an alkyl group having ¹ to 3 carbon atoms or an aryl group, and R ² represents a hydrogen atom, an alkyl group or alkenyl having 1 to 8 carbon atoms. A group or a benzyl group, A represents an alkylene group having 2 to 8 carbon atoms, and n represents an integer of 1 to 4]
And (3) an aluminum chelate obtained by reaction with at least one ketoenol-type tautomeric compound different from the β-ketoester represented by the general formula (L1). Curing agent for resin. The keto enol-type tautomeric compound (3) is a β-keto ester represented by the following general formula (L2), a β-ketoamide represented by the following general formula (L3), and β- represented by the following general formula (L4). Diketone:

[In the general formula (L2), R ³ represents an alkyl group or aryl group having 1 to 3 carbon atoms, and R ⁴ represents an alkyl group or alkenyl group having 1 to 18 carbon atoms, or Represents a benzyl group, and in general formula (L3), R ⁵ represents an alkyl group having 1 to 4 carbon atoms, and R ⁶ and R ⁷ are each independently 1 to 8 carbon atoms. In the general formula (L4), R ⁸ and R ⁹ each independently represent 1 or an unsubstituted or substituted alkyl group having the following formula: Represents an alkyl group having up to 8 carbon atoms or an aryl group]
The hardening | curing agent for resins of Claim 2 chosen from these.   A curing agent component comprising the curing agent for a resin according to any one of claims 1 to 3, and a resin component containing at least one selected from a water-soluble acrylic resin and an epoxy resin. A curable resin composition.   The curable resin composition according to claim 4, further comprising an epoxy component containing a polyepoxy compound.