WO2018096781A1 - Method for producing modified carbodiimide amine - Google Patents

Abstract

This method for producing a modified carbodiimide amine (X) includes a method [α] or a method [β]. In method [α], an amine compound (A) represented by formula (1) is reacted with a compound (B) having a number average molecular weight of 300 or more, followed by reacting with a carbodiimide compound (C) to obtain the modified carbodiimide amine (X). In the method [β], the amine compound (A) represented by formula (1) is reacted with the carbodiimide compound (C), followed by reacting with the compound (B) having a number average molecular weight of 300 or more to obtain the modified carbodiimide amine (X). [In formula (1), R¹ to R⁴ are each the same as defined in the specification.]

Description

Method for producing modified carbodiimidoamine

The present invention relates to a novel method for producing an amine compound, specifically, a modified carbodiimide amine having a substituent having a large molecular weight.

An amine compound (particularly a strong base amine compound) is a compound useful as a catalyst in various chemical reactions, and can be used, for example, as a catalyst for dissociating a blocking agent in a block isocyanate-based thermosetting coating composition. Here, the amine compound having a substituent having a large molecular weight is particularly useful because it does not deteriorate various performances (for example, water resistance, weather resistance, etc.) in the final product (for example, coating film, film, resin molding, etc.). There is expected.
Patent Document 1 discloses a block polyisocyanate, tertiary and / or quaternary amine system obtained from a polyisocyanate composed of an epoxy resin and / or an acrylic resin having both an epoxy group and a hydroxyl group, an aliphatic and / or alicyclic diisocyanate. A low-temperature curable one-component coating composition containing a compound as an essential component is described.
Patent Document 2 describes an amine compound catalyst for the reaction between an isocyanate and an alcohol for producing a polyurethane polymer.
Patent Documents 3 and 4 describe thermosetting coating compositions containing a hydroxyl group-containing resin (amino group-containing resin), a blocked isocyanate curing agent, and an amine compound catalyst.

Japanese Laid-Open Patent Publication No. 8-302280 Japanese National Special Table 2012-1215189 Japanese Unexamined Patent Publication No. 2016-138203 Japanese Unexamined Patent Publication No. 2016-138202

However, the amine compounds described in Patent Documents 1 to 4 may not have sufficient curability when cross-linked at low temperatures, and the coating performance (water resistance, etc.) may decrease when the catalyst content is increased. It was. Moreover, when the molecular weight of the amine catalyst is small, the water resistance of the coating film may not be sufficient.
The problem to be solved by the present invention is to produce an amine compound (carbodiimide amine modified product) having a high catalytic effect and a large molecular weight with high efficiency (low by-product and high purity), and the amine modification It is to obtain good curability and coating film performance (particularly water resistance in warm water) by using the product as a catalyst for the blocked isocyanate curing agent.

As a result of intensive studies to solve the above problems, the inventors have found that the above problems can be solved by a carbodiimide amine-modified product obtained by reacting a carbodiimide, an amine compound and a compound having a number average molecular weight of 300 or more, The present invention has been completed. That is, this invention provides the manufacturing method of the following carbodiimide amine modified products.
[1]
A method for producing a modified carbodiimide amine (X) by the following method [α] or method [β].
[Α] An amine compound (A) having two or more nitrogen atoms represented by the following formula (1) is reacted with a compound (B) having a number average molecular weight of 300 or more, and then a carbodiimide compound (C) is reacted to form a carbodiimide. An amine-modified product (X) is obtained.
[Β] An amine compound (A) having two or more nitrogen atoms represented by the following formula (1) is reacted with a carbodiimide compound (C), and then a compound (B) having a number average molecular weight of 300 or more is reacted to react with the carbodiimide. An amine-modified product (X) is obtained.

[In Formula (1), R ¹ to R ⁴ are each independently a hydrogen atom or an organic group having 1 or more carbon atoms, and the organic group is selected from the group consisting of an oxygen atom, a nitrogen atom, a sulfur atom, and a halogen atom. May contain one or more atoms. X is an organic group having 1 or more carbon atoms, and the organic group may contain one or more atoms selected from the group consisting of an oxygen atom, a nitrogen atom, a sulfur atom, and a halogen atom. n is an integer of 1 to 3. ]
[2]
The production method according to [1], wherein the amine compound (A) is a compound represented by the following formula (1-1).

[In the formula ^(1-1), the definition of R ^1, R 2, ^{R 4} have the same meanings as ^{R 1,} R 2, ^{R 4} of formula (1). R ³¹ and R ³² have the same meaning as R ^{3 in} formula (1). m is an integer of 0 to 3. p and q are each independently an integer of 1 to 6. ]
[3]
The production method according to [1], wherein X of the amine compound (A) is a structure represented by the following formula (3).

[In Formula (3), Y is a hydrogen atom or an organic group having 1 or more carbon atoms, and the organic group may include one or more atoms selected from the group consisting of an oxygen atom, a nitrogen atom, a sulfur atom, and a halogen atom. Good. * Is a bond. ]
[4]
The production method according to any one of [1] to [3], wherein the carbodiimide compound (C) is a compound represented by the following formula (2).
R ⁵ -N = C = N-R ⁶ (2)
[In Formula (2), R ⁵ and R ⁶ are each independently an organic group having 1 or more carbon atoms, and the organic group is one or more selected from the group consisting of an oxygen atom, a nitrogen atom, a sulfur atom, and a halogen atom. May be included. ]
[5]
A carbodiimide amine modified product (X) obtained by the production method according to any one of [1] to [4], a hydroxyl group-containing resin (Y), and a blocked polyisocyanate curing agent (Z) are mixed and heated. A method for producing a thermosetting coating composition, wherein a curable coating composition is obtained.
[6]
A method for producing a coated article, wherein a coated article is obtained by coating the article to be coated with the thermosetting coating composition obtained by the production method according to [5].

According to the production method of the present invention, a carbodiimide amine-modified product having a high molecular weight substituent can be efficiently produced (the by-product is low and a carbodiimide amine-modified product can be obtained with high purity). The curability and coating film performance (water resistance, etc.) of the thermosetting paint can be improved by the catalytic effect of the modified carbodiimide amine.

Hereinafter, the manufacturing method of the carbodiimide amine modified material of this invention is demonstrated.
In the present specification, all percentages and parts represented by mass are the same as percentages and parts represented by weight.

The present invention relates to a method for producing a modified carbodiimide amine having a high molecular weight substituent.

The modified carbodiimide amine (X) of the present invention can be obtained by the following method [α] or method [β].
[Α] An amine compound (A) having two or more nitrogen atoms represented by the following formula (1) is reacted with a compound (B) having a number average molecular weight of 300 or more, and then a carbodiimide compound (C) is reacted to form a carbodiimide. An amine-modified product (X) is obtained.
[Β] An amine compound (A) having two or more nitrogen atoms represented by the following formula (1) is reacted with a carbodiimide compound (C), and then a compound (B) having a number average molecular weight of 300 or more is reacted to react with the carbodiimide. An amine-modified product (X) is obtained.

In the formula (1), R ¹ to R ⁴ are each independently a hydrogen atom or an organic group having 1 or more carbon atoms, and the organic group is selected from the group consisting of an oxygen atom, a nitrogen atom, a sulfur atom, and a halogen atom. It may contain one or more atoms. X is an organic group having 1 or more carbon atoms, and the organic group may contain one or more atoms selected from the group consisting of an oxygen atom, a nitrogen atom, a sulfur atom, and a halogen atom. n is an integer of 1 to 3.

[Amine compound (A)]
The amine compound (A) is a starting material and has two or more nitrogen atoms.
In the formula (1), R ¹ to R ⁴ are each independently a hydrogen atom or an organic group having 1 or more carbon atoms, and the organic group preferably has 1 to 6 carbon atoms. Further, the organic group may contain one or more atoms selected from the group consisting of an oxygen atom, a nitrogen atom, a sulfur atom and a halogen atom. From the viewpoint of curability, R ¹ to R ⁴ are specifically preferably at least one selected from a hydrogen atom, a methyl group, an ethyl group, a propyl group, a cyclohexyl group, and a benzyl group.

In the formula (1), n is an integer of 1 to 3, preferably 1 or 2, and more preferably 1.

X is an organic group having 1 or more carbon atoms, preferably an organic group having 1 to 6 carbon atoms. The organic group may contain one or more atoms selected from the group consisting of an oxygen atom, a nitrogen atom, a sulfur atom and a halogen atom.

X may have a C = N structure. The C═N structure serves as a reaction starting point with a carbodiimide compound (C) described later.
When X has a C═N structure, X is more preferably a structure represented by the following formula (3). With this structure, the resulting carbodiimide amine modified product (X) has a conjugated structure, and the composition is cured by blending the carbodiimide amine modified product (X) (conjugated guanidine) into the thermosetting coating composition. Improves.

In the formula (3), Y is a hydrogen atom or an organic group having 1 or more carbon atoms. In the case of an organic group, the number of carbon atoms is preferably 1-6. The organic group may contain one or more atoms selected from the group consisting of oxygen atom, nitrogen atom, sulfur atom and halogen atom. * Is a bond.

When X contains a C═N structure, the amine compound (A) includes 1,1,3,3-tetramethylguanidine, 1,1,3-trimethylguanidine, 1,1-dimethylguanidine, 1,3 -Guanidine compounds such as dimethylguanidine and 1-methylguanidine, and derivatives thereof.

X can have an alkylene structure. In this case, the amine compound (A) represented by the formula (1) preferably has a structure represented by the following formula (1-1).

In formula ^(1-1), the definition of R ^1, R 2, ^{R 4} have the same meanings as ^{R 1,} R 2, ^{R 4} of formula (1). R ³¹ and R ³² have the same meaning as R ^{3 in} formula (1). m is an integer of 0 to 3. p and q are each independently an integer of 1 to 6.

Examples of the amine compound (A) represented by the formula (1-1) include ethylenediamine, N-methylethylenediamine, N, N-dimethylethylenediamine, N, N, N′-trimethylethylenediamine, propylenediamine, butylenediamine, hexa Alkylenediamines such as methylenediamine; dialkylenetriamines such as diethylenetriamine, dipropylenetriamine and bis (hexamethylene) triami; trialkylenetetramines such as triethylenetetramine and tripropylenetetramine; tetraethylenes such as tetraethylenepentamine and tetrapropylpentamine Examples include alkylenepentamine and derivatives thereof.
In addition, an amine obtained by ketiminizing the primary amino group of the amine can also be used. These can be used alone or in combination of two or more.
Of these, alkylene diamine, dialkylene triamine, and derivatives thereof are preferable, and dialkylene triamine and derivatives thereof are more preferable.

[Compound (B) having a number average molecular weight of 300 or more]
The compound (B) is a compound having a number average molecular weight of 300 or more, preferably a compound having a number average molecular weight of 600 or more. The compound (B) is a reaction raw material for reacting with the amine compound (A) to introduce a high molecular weight group into the target product carbodiimide amine-modified product (X). Specifically, a compound that can react with an active hydrogen group (for example, a primary amino group, a secondary amino group, or an active hydrogen group possessed by a hydroxyl group) of an amine compound (A) to form an organic group (for example, an epoxy group Compounds having an isocyanate group), and examples thereof include acrylic resins, polyester resins, urethane resins, epoxy resins, polyisocyanate compounds having one or more epoxy groups or isocyanate groups.
The epoxy resin (Y3-1) described later can be suitably used as the epoxy resin, and the polyisocyanate compound (Z-1) described later can be preferably used as the polyisocyanate compound.

[Carbodiimide compound (C)]
The carbodiimide compound (C) reacts with the amine compound (A) to produce a carbodiimide amine modified product (X). The carbodiimide compound (C) is not limited as long as it has a —N═C═N— structure, but is preferably a compound represented by the following formula (2).
R ⁵ -N = C = N-R ⁶ (2)
In the formula (2), R ⁵ and R ⁶ are each independently an organic group having 1 or more carbon atoms, and the organic group is one or more selected from the group consisting of an oxygen atom, a nitrogen atom, a sulfur atom, and a halogen atom. It may contain atoms.

R ⁵ and R ⁶ are each independently preferably an organic group having 1 to 6 carbon atoms, and more preferably a linear or cyclic alkyl group having 1 to 6 carbon atoms. Specific examples include a methyl group, an ethyl group, a propyl group, an isopropyl group, a cyclohexyl group, and the like, and an isopropyl group and a cyclohexyl group are preferable.

The case where n in the amine compound (A) is 1 and X is a structure represented by the formula (3), and the carbodiimide compound (C) is a compound represented by the formula (2) An example shows the production method of the present invention. The upper part is a synthetic scheme [α] in which the compound (B) is first reacted with the compound (A), and the lower part is a synthetic scheme [β] in which the compound (C) is reacted first. The compound (B) having a number average molecular weight of 300 or more reacts with and adds to any of the groups R ¹ to R ⁶ and Y. The following scheme shows the case where the compound (B) is added to the group R ¹ and R ¹ becomes R ^{1 ′} .

Further, in the case where the amine compound (A) is a compound represented by the formula (1-1) and the carbodiimide compound (C) is a compound represented by the formula (2) as an example, The manufacturing method of invention is shown. The upper part is a synthetic scheme [α] in which the compound (B) is first reacted with the compound (A), and the lower part is a synthetic scheme [β] in which the compound (C) is reacted first. The compound (B) having a number average molecular weight of 300 or more reacts with any of the groups R ¹ to R ⁶ to be added. The following scheme shows the case where compound (B) is added to group R ¹ and R ¹ is R ^{1 ′} .

The modified product (X) can be synthesized by any of the schemes [α] and [β], but the upper synthesis scheme [α] is preferred from the viewpoint of obtaining a high yield.

The carbodiimide amine modified product (X) produced in the present invention preferably has a non-cyclic guanidine structure. The “acyclic” guanidine structure means that the guanidine structure (RN═C (NR ₂ ) ₂ ) does not form a ring. Therefore, when each organic group or the like in the modified carbodiimide amine (X) has a cyclic structure (for example, when any of R ¹ to R ⁶ has a cyclic organic group such as a cyclohexyl group or a benzyl group), The guanidine structure is “non-cyclic”.

[Reaction conditions: Scheme (α)]
In the reaction vessel, the amine compound (A) and the compound (B) having a number average molecular weight of 300 or more are mixed at a molar ratio of amine functional group: reactive functional group of compound (B) of 0.4: 1 to 2. Mix at a ratio of 0: 1, preferably 0.7: 1 to 1.3: 1 and react in a solvent. As the solvent, any solvent that can dissolve the compounds (A), (B) and (C) can be used without particular limitation. The heating temperature is preferably 80 to 120 ° C., and the reaction pressure is preferably normal pressure. If necessary, the reaction product can be purified by filtration, distillation or the like.
The obtained product and the carbodiimide compound (C) are in a molar ratio of amine functional group to carbodiimide functional group of 1: 0.4 to 1: 2, preferably 1: 0.7 to 1: 1. Mix at a ratio of 3 and react in solvent. As the solvent, any solvent that can dissolve the compounds (A), (B) and (C) can be used without particular limitation. The heating temperature is preferably 60 to 100 ° C., and the reaction pressure is preferably normal pressure. If necessary, the reaction product is purified by filtration, distillation, etc. to obtain a modified carbodiimide amine (X).

[Reaction conditions: Scheme (β)]
In the reaction vessel, the amine compound (A) and the carbodiimide compound (C) are in a molar ratio of amine functional group to carbodiimide functional group of 1: 0.4 to 1: 2, preferably 1: 0.7 to Mix in a ratio of 1: 1.3 and react in a solvent. As the solvent, any solvent that can dissolve the compounds (A), (B) and (C) can be used without particular limitation. The heating temperature is preferably 60 to 100 ° C., and the reaction pressure is preferably normal pressure. If necessary, the reaction product can be purified by filtration, distillation or the like.
The obtained product and the compound (B) having a number average molecular weight of 300 or more are in a molar ratio of the functional group of amine functional group: reactive functional group of compound (B) of 1: 0.4 to 1: 2, preferably Mix at a ratio of 1: 0.7 to 1: 1.3 and react in a solvent. As the solvent, any solvent that can dissolve the compounds (A), (B) and (C) can be used without particular limitation. The heating temperature is preferably 80 to 120 ° C., and the reaction pressure is preferably normal pressure. If necessary, the reaction product is purified by filtration, distillation, etc. to obtain a modified carbodiimide amine (X).

[Thermosetting paint composition]
The carbodiimide amine modified product (X) obtained by the production method of the present invention can be used as a catalyst for promoting the curing reaction in a thermosetting coating composition containing a blocked isocyanate curing agent.
Hereinafter, it describes about the thermosetting coating composition (henceforth the thermosetting coating composition of this invention) containing the carbodiimide amine modified material (X) of this invention.

The thermosetting coating composition of the present invention contains a carbodiimide amine-modified product (X), a hydroxyl group-containing resin (Y), and a blocked polyisocyanate curing agent (Z).
The blocked isocyanate does not react with the resin at room temperature, but when heated, the blocking agent dissociates to regenerate the isocyanate group, and the crosslinking reaction with the resin having active hydrogen proceeds. For this reason, there is no restriction | limiting in pot life, It can be set as a one-pack type coating material, Furthermore, application to the water-based coating material which uses water and alcohol which have active hydrogen as a medium is also possible. The carbodiimide amine modified product (X) of the present invention has a function as a catalyst for dissociating the blocking agent by heat (for example, 100 ° C. or more), whereby the free isocyanate group is regenerated, and the hydroxyl group-containing resin (Y) and A cross-linking reaction proceeds by reacting with an isocyanate group. Since the crosslinking reaction proceeds without using a conventional metal catalyst, the present invention can provide an environment-friendly thermosetting coating composition. The modified carbodiimide amine (X) also functions as a catalyst for the transesterification reaction between the hydroxyl group-containing resin (Y) and the blocked isocyanate group. For example, a carbamate transesterification reaction is performed as a strong base catalyst. This is due to the high proton acceptability (stabilization of cationic species) due to the guanidine structure of the modified carbodiimide amine (X).

As the hydroxyl group-containing resin (Y), any known resin can be used without particular limitation as long as it has a hydroxyl group and can be crosslinked with the blocked polyisocyanate curing agent (Z). A reactive functional group having active hydrogen such as an amino group, a carboxyl group, or an active methylene group, an epoxy group, a carboxylic anhydride group, or the like can be used in combination with a hydroxyl group.

Examples of the hydroxyl group-containing resin (Y) include acrylic resins, polyester resins, epoxy resins, alkyd resins, polyether resins, polyurethane resins, polyamide resins, and the like. These may be used alone or in combination of two or more. Can be used in combination. Especially, it is preferable that it is at least 1 sort (s) chosen from an acrylic resin (Y1), a polyester resin (Y2), and an epoxy resin (Y3).

The hydroxyl group-containing resin (Y) may be in a dissolved state in the thermosetting coating composition, or may be in a dispersed state (for example, an emulsion state in an aqueous solvent). In the case of a dispersed state, it may be a crosslinked resin particle.
Acrylic resin (Y1)
The acrylic resin (Y1) that can be used in the thermosetting coating composition of the present invention can be produced by radical copolymerization of an acrylic monomer.
Examples of the acrylic monomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and an addition product of 2-hydroxyethyl (meth) acrylate and caprolactone. Hydroxyl group-containing acrylic monomers such as, for example, Placelel FA-2 and FM-3 manufactured by Daicel Corporation; aromatic vinyl monomers such as styrene, vinyltoluene and α-methylstyrene; methyl (meth) acrylate, ethyl (Meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, cyclohexyl (meth) acrylate , 2-ethylhexyl (meth) acrylate, polyalkylene glycol (meth) acrylate, isobornyl (meth) acrylate, (meth) acrylic acid, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) Examples thereof include acrylate, N, N-dimethylaminopropyl (meth) acrylate, N, N-di-t-butylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylamide and the like. These can be used alone or in combination of two or more.
In the present specification, (meth) acryl means acryl or methacryl, and (meth) acrylate means acrylate or methacrylate.

The acrylic resin (Y1) can be obtained by subjecting the above monomer to a radical copolymerization reaction by a known method.
The hydroxyl value of the acrylic resin (Y1) is usually in the range of 0.1 to 300 mgKOH / g, preferably in the range of 10 to 200 mgKOH / g, and the weight average molecular weight is usually in the range of 1,000 to 100,000. Of these, a range of 2,000 to 30,000 is preferable.

In this specification, the number average molecular weight and the weight average molecular weight are the retention time (retention capacity) measured using a gel permeation chromatograph (GPC) and the retention time of a standard polystyrene with a known molecular weight measured under the same conditions. (Retention capacity) is a value obtained by converting to the molecular weight of polystyrene. Specifically, “HLC8120GPC” (trade name, manufactured by Tosoh Corporation) is used as a gel permeation chromatograph, and “TSKgel G-4000HXL”, “TSKgel G-3000HXL”, “TSKgel G-2500HXL” are used as columns. ”And“ TSKgel G-2000HXL ”(trade names, all manufactured by Tosoh Corporation), and can be measured under the conditions of mobile phase tetrahydrofuran, measurement temperature 40 ° C., flow rate 1 mL / min, and detector RI. it can.

Polyester resin (Y2)
The polyester resin (Y2) that can be used in the thermosetting coating composition of the present invention can be produced by an esterification reaction and / or a transesterification reaction of an acid component and an alcohol component.
As the acid component, a compound usually used as an acid component can be used without particular limitation in the production of a polyester resin. Examples of the acid component include alicyclic polybasic acids, aliphatic polybasic acids, aromatic polybasic acids, aromatic monocarboxylic acids, aliphatic monocarboxylic acids, alicyclic monocarboxylic acids, and those acids. A lower alkyl esterified product or the like can be used.
Generally, an alicyclic polybasic acid is a compound having one or more alicyclic structures (mainly 4- to 6-membered rings) and two or more carboxyl groups in one molecule, an acid anhydride of the compound, and the compound The esterified product.
The aliphatic polybasic acid is generally an aliphatic compound having two or more carboxyl groups in one molecule, an acid anhydride of the compound, and an esterified product of the compound.
The aromatic polybasic acid is generally an aromatic compound having two or more carboxyl groups in one molecule, an acid anhydride of the aromatic compound, and an esterified product of the aromatic compound.
Moreover, aromatic monocarboxylic acid, aliphatic monocarboxylic acid, alicyclic monocarboxylic acid, etc. can also be used as needed.
As the alcohol component, a compound usually used as an alcohol component can be used without particular limitation in the production of the polyester resin, but dihydric alcohols such as alicyclic diol, aliphatic diol, aromatic diol, and 3 What contains the polyhydric alcohol more than valence is preferable.

As a manufacturing method of the said polyester resin (Y2), it can manufacture by reacting the said acid component and alcohol component by a well-known method.
The polyester resin (Y2) can also be modified with a fatty acid, oil, polyisocyanate compound, epoxy compound or the like during the preparation of the resin or after the esterification reaction and / or after the transesterification reaction.
The number average molecular weight of the polyester resin (Y2) is usually 1,000 to 20,000, preferably 1,050 to 10,000, more preferably 1,100 to 5,000, from the viewpoint of finish. It is preferable to be within the range.
The hydroxyl value of the polyester resin (Y2) is usually 20 to 300 mgKOH / g, preferably 30 to 250 mgKOH / g, more preferably 40 to 180 mgKOH / g, from the viewpoint of curability of the resulting coating film. It is preferable to be within the range.

Epoxy resin (Y3)
The epoxy resin (Y3) that can be used in the thermosetting coating composition of the present invention can be obtained by reacting an epoxy resin (Y3-1) with a modifier (Y3-2).
The epoxy resin (Y3-1) that can be used as a raw material for the epoxy resin (Y3) is a compound having at least one, preferably two or more epoxy groups in one molecule, and has a molecular weight of at least 300, Preferably a number average molecular weight in the range of 400 to 4,000, more preferably in the range of 800 to 2,500 and an epoxy equivalent weight in the range of at least 160, preferably 180 to 2,500, more preferably 400 to 1,500. What you have is suitable. As such an epoxy resin (Y3-1), for example, a resin obtained by a reaction between a polyphenol compound and an epihalohydrin (for example, epichlorohydrin) can be used.
Examples of the polyphenol compound used for forming the epoxy resin (Y3-1) include bis (4-hydroxyphenyl) -2,2-propane [bisphenol A] and bis (4-hydroxyphenyl) methane [bisphenol. F], bis (4-hydroxycyclohexyl) methane [hydrogenated bisphenol F], 2,2-bis (4-hydroxycyclohexyl) propane [hydrogenated bisphenol A], 4,4′-dihydroxybenzophenone, bis (4-hydroxy Phenyl) -1,1-ethane, bis (4-hydroxyphenyl) -1,1-isobutane, bis (4-hydroxy-3-tert-butyl-phenyl) -2,2-propane, bis (2-hydroxynaphthyl) ) Methane, tetra (4-hydroxyphenyl) -1,1,2,2-eta 4,4'-dihydroxydiphenylsulfone, phenol novolak, cresol novolak, and the like.
As the epoxy resin (Y3-1) obtained by the reaction of a polyphenol compound and epihalohydrin, a resin represented by the following formula derived from bisphenol A is particularly preferable.

Here, those represented by n = 0 to 8 are preferred.
Examples of such commercially available epoxy resin (Y3-1) include those sold by Mitsubishi Chemical Corporation under the trade names of jER828EL, jER1002, jER1004, and jER1007.
The modifier (Y3-2) that can be used as a raw material for the epoxy resin (Y3) is not particularly limited as long as it is a component having reactivity with the epoxy resin (Y3-1). , Monohydric alcohols, acidic compounds, phenols, amine compounds, lactones, isocyanate compounds, xylene formaldehyde compounds, and the like.

Examples of the polyhydric alcohol include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, , 5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 2-methyl-1,3-propanesiol, 3-methyl-1 , 5-pentanediol, 2-methylpentane-2,4-diol, 2,2,4-trimethyl-1,3-pentanediol, triethylene glycol, 2-butyl-2-ethyl-1,3-propanediol , Tricyclodecane dimethanol, triethylene glycol, neopentyl glycol, , 4-cyclohexanediol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, bisphenol A, bisphenol F, hydrogenated bisphenol A, hydrogenated bisphenol F and other dihydric alcohols; polyethylene glycol, polypropylene glycol, poly Examples include polyether diols such as butylene glycol; trihydric alcohols such as glycerin, trimethylolpropane and tris (2-hydroxyethyl) isocyanurate; tetrahydric alcohols such as pentaerythritol; polyester polyols and acrylic polyols.
Examples of the monohydric alcohol include methanol, ethanol, n-propanol, isopropanol, n-butanol, 2-butanol, pentanol, hexanol, n-octanol, 2-ethylhexanol, dodecyl alcohol, stearyl alcohol, benzyl alcohol, and the like. Is mentioned.
Examples of the acidic compound include acidic compounds such as acetic acid, propionic acid, butyric acid, valeric acid, acrylic acid, oleic acid, glycolic acid, lactic acid, benzoic acid, gallic acid, fatty acid, and dibasic acid.
Examples of the phenols include phenol, cresol, ethylphenol, para-tert-butylphenol, nonylphenol, catechol, resorcinol, 4-tert-butylcatechol and the like.
The amine compound is not particularly limited as long as it is an amine compound containing at least one active hydrogen that reacts with an epoxy group. For example, monomethylamine, dimethylamine, monoethylamine, diethylamine, monoisopropylamine, diisopropylamine, Mono- or di-alkylamines such as monobutylamine and dibutylamine; alkanols such as monoethanolamine, diethanolamine, mono (2-hydroxypropyl) amine, di (2-hydroxypropyl) amine, monomethylaminoethanol and monoethylaminoethanol Amine; ethylenediamine, propylenediamine, butylenediamine, hexamethylenediamine, tetraethylenepentamine, pentaethylenehexamine, diethylaminopropylamine Emissions, diethylenetriamine, alkylene polyamine such as triethylene tetramine; ethyleneimine, alkylene imine such as propylene imine; piperazine, morpholine, and cyclic amines, such as pyrazine and the like. These amines and amines obtained by ketiminizing primary amines can also be used in combination.
These can be used individually by 1 type or in combination of 2 or more types.

The epoxy resin (Y3) can be produced by reacting the epoxy resin (Y3-1) and the modifier (Y3-2) by a known method.
The number average molecular weight of the epoxy resin (Y3) is usually in the range of 1,000 to 50,000, preferably 1,300 to 20,000, from the viewpoints of coating stability, finish, corrosion resistance, and the like. And more preferably in the range of 1,600 to 10,000. The hydroxyl value of the epoxy resin (Y3) is usually 10 to 300 mgKOH / g, preferably 20 to 250 mgKOH / g, more preferably 30 to 200 mgKOH / g, from the viewpoint of curability of the resulting coating film. Preferably it is.

Blocked polyisocyanate curing agent (Z)
The blocked polyisocyanate curing agent (Z) that can be used in the thermosetting coating composition of the present invention is an approximately chemical theoretical amount of the polyisocyanate compound (Z-1) and the isocyanate blocking agent (Z-2). It is an addition reaction product. As the polyisocyanate compound (Z-1) used in the blocked polyisocyanate curing agent (Z), known compounds can be used without particular limitation, and examples thereof include tolylene diisocyanate, xylylene diisocyanate, phenylene diisocyanate, Diphenylmethane-2,2′-diisocyanate, diphenylmethane-2,4′-diisocyanate, diphenylmethane-4,4′-diisocyanate, crude MDI [polymethylenepolyphenylisocyanate], bis (isocyanatemethyl) cyclohexane, tetramethylenediisocyanate, hexamethylene Aromatic, aliphatic or alicyclic polyisocyanate compounds such as diisocyanate, methylene diisocyanate and isophorone diisocyanate; Cyclized polymers or biuret body of the object; or a combination thereof can be mentioned.

On the other hand, the isocyanate blocking agent (Z-2) is added and blocked to the isocyanate group of the polyisocyanate compound (Z-1), and the blocked polyisocyanate compound produced by the addition is stable at room temperature. However, when heated to the baking temperature of the coating film (usually about 80 to about 200 ° C.), it is desirable that the blocking agent dissociates to regenerate free isocyanate groups.

Examples of the isocyanate blocking agent (Z-2) used in the blocked polyisocyanate curing agent (Z) include oxime compounds such as methyl ethyl ketoxime and cyclohexanone oxime; phenols such as phenol, para-t-butylphenol and cresol Compounds; n-butanol, 2-ethylhexanol, phenyl carbinol, methyl phenyl carbinol, alcohol compounds such as ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, ethylene glycol, propylene glycol; ε-caprolactam, γ-butyrolactam, etc. Lactam compounds: dimethyl malonate, diethyl malonate, diisopropyl malonate, ethyl acetoacetate, methyl acetoacetate, acetylacetone, etc. Active methylene compounds; pyrazole compounds such as dimethylpyrazole, and the like. These may be used alone or in combination of two or more.

Among these, from the viewpoint of dissociation temperature and paint stability, it is preferable to use at least one selected from alcohol compounds, pyrazole compounds, oxime compounds, and lactam compounds, and alcohol compounds are particularly preferable.

As a compounding ratio of the hydroxyl group-containing resin (Y) and the blocked polyisocyanate curing agent (Z) in the thermosetting coating composition of the present invention, the component (Y) is based on the total mass of the resin solid content of the coating composition. However, it is usually 10 to 90% by mass, preferably 20 to 80% by mass, and the component (Z) is usually in the range of 10 to 60% by mass, preferably 15 to 55% by mass. It is also preferable for obtaining a coated article having excellent resistance. Outside the above range, either the coating properties or the coating film performance may be impaired, which is not preferable.
In addition, the content of the carbodiimide amine-modified product (X) is based on the resin solid total mass of the coating composition, and when an organic group having a molecular weight of 300 or more is added, in the mass excluding the group, It is usually from 0.01 to 30% by mass, preferably from 0.1 to 10% by mass, from the viewpoint of curability.

The thermosetting coating composition of the present invention is not particularly limited. For example, in addition to components (X) to (Z), a pigment dispersion paste, a solvent such as water or an organic solvent, if necessary, A neutralizer, a surfactant, a surface conditioner, a thickener, an anti-settling agent, an ultraviolet absorber, a light stabilizer, an antifoaming agent, a dissociation catalyst, a plasticizer, and the like can be contained.

Coating film formation methods using the thermosetting coating composition of the present invention include brush coating, roller coating, dipping coating, bar coder coating, applicator coating, curtain coating, spray coating, rotary atomization coating, electrodeposition coating, etc. Any known coating method can be used without particular limitation.

The film thickness of the coating film is not particularly limited, but can generally be in the range of 5 to 60 μm, preferably 10 to 40 μm based on the dry coating film.

The coating film is baked and dried using a drying facility such as an electric hot air dryer or a gas hot air dryer at a temperature of 60 to 300 ° C., preferably 80 to 200 ° C., at the surface temperature of the coating. For 3 to 180 minutes, preferably 10 to 50 minutes. A cured coating film can be obtained by baking and drying.

Examples of the object to be coated of the present invention include automobile bodies, automobile parts, motorcycle parts, household equipment, other equipment, etc., and materials include metals, plastics, inorganic materials, wood, fiber materials, etc. There is no limit. In the case of a metal material, for example, a surface that has been subjected to a surface treatment such as phosphate conversion treatment or chromate treatment after washing with alkali degreasing as necessary can be used. An article to be coated with paint or the like may be used.
A coated article can be obtained by coating the above-mentioned article to be coated with the thermosetting coating composition of the present invention.

Hereinafter, the present invention will be described in more detail with reference to production examples, examples and comparative examples, but the present invention is not limited thereto. In each example, “parts” indicates mass parts, and “%” indicates mass%.

Production of hydroxyl group-containing resin (Y) Production Example 1 (acrylic resin)
31 parts of propylene glycol monomethyl ether was charged into a four-necked flask equipped with a stirrer, a thermometer, a condenser, and a nitrogen gas inlet, and the temperature was raised to 110 ° C. under nitrogen gas flow. After reaching 110 ° C., the nitrogen gas flow was stopped, 22 parts 2-hydroxyethyl acrylate, 30 parts methyl methacrylate, 22 parts 2-ethylhexyl acrylate, 25 parts styrene, 1 part acrylic acid, and 2,2 ′ A mixture of 4 parts of azobis (isobutyronitrile) was added dropwise over 4 hours. Next, after aging for 2 hours while bubbling nitrogen gas at 110 ° C., the solution was cooled to 100 ° C. and diluted with propylene glycol monomethyl ether to obtain an acrylic resin (Y-1) solution having a solid content of 60%. .
The acrylic resin (Y-1) had a weight average molecular weight of 15,000 and a hydroxyl value of 106 mgKOH / g.

Production Example 2 (Epoxy resin)
To a flask equipped with a stirrer, thermometer, nitrogen inlet tube and reflux condenser, 950 parts of jER1001 (trade name, manufactured by Mitsubishi Chemical Corporation, epoxy resin, epoxy equivalent 475, number average molecular weight 900), 1,6-hexanediol 236 parts, 0.2 g of dimethylbenzylamine was added and reacted at 200 ° C. until the epoxy equivalent reached 30,000 or more. Further, ethylene glycol monobutyl ether was added to obtain an epoxy resin (Y-2) solution having a solid content of 60%. Obtained. The number average molecular weight of the epoxy resin (Y-2) was 2,500.

Production of blocked polyisocyanate curing agent (Z) Production Example 3
A four-necked flask equipped with a stirrer, a heating device, a cooling device, and a decompression device was charged with 272 parts of hexamethylene diisocyanate and 214 parts of methyl ethyl ketone and heated to 60 ° C. Subsequently, 169 parts of methyl ethyl ketoxime was gradually added over 1 hour with stirring. Then, after making it react at 60 degreeC for 2 hours, 59 parts of trimethylol propane was gradually added so that temperature might not become 70 degreeC or more. Under stirring, the reaction mixture was reacted at 60 ° C. until no free isocyanate groups were detected by infrared spectroscopy. After completion of the reaction, a blocked polyisocyanate curing agent (Z-1) having a solid content of 70% was obtained. The resulting blocked polyisocyanate curing agent (Z-1) had an NCO content of 16.4%.

Production of carbodiimide amine-modified product (X) Among the carbodiimide amine-modified products (X-1γ) to (X-10) shown in Table 1 and Table 2 below, carbodiimide amine-modified products (X-1γ) to (X-1γ) to ( X-8) was produced.
In addition, the manufactured carbodiimide amine modified product may contain by-products or unreacted substances in addition to the compounds in Tables 1 and 2.
The described epoxy amine value was measured by the following method.

<Measurement method of epoxy amine value>
The epoxy amine value (meq / g) of the present invention is the total number of millimoles of epoxy functional groups and amine functional groups per gram of the sample including the solvent. Epoxy equivalent (gram number of the component containing 1 gram equivalent of epoxy group) measured by JIS K7236: 2009, both epoxy functional group and amine functional group are measured in the sample of the present invention. It is a calculated value.
Epoxy amine value (meq / g) = 1000 / epoxy equivalent (measurement result of JIS K7236: 2009)

Me: methyl group, Et: ethyl group, iPr: isopropyl group, Cy: cyclohexyl group For those not described, hydrogen atom EP1: jER828 (trade name, manufactured by Mitsubishi Chemical Corporation, epoxy resin, epoxy equivalent 190, number average molecular weight 370 )
EP2: jER1001 (trade name, manufactured by Mitsubishi Chemical Corporation, epoxy resin, epoxy equivalent 475, number average molecular weight 900)

Comparative Example 1 Modified carbodiimide amine (X-1γ)
To a flask equipped with a stirrer, a thermometer, and a reflux condenser, 126 parts of diisopropylcarbodiimide, 59 parts of isopropylamine, and 275 parts of t-butanol were added, and the reaction was performed while heating under reflux. As a result of measurement by infrared absorption spectrum (hereinafter referred to as IR), it was confirmed that absorption due to carbodiimide at 2120 cm ⁻¹ was almost eliminated. After removing t-butanol under reduced pressure, ethylene glycol monobutyl ether was added to adjust the solid content to obtain a carbodiimide amine-modified (X-1γ) solution having a solid content of 50%.

Comparative Example 2 Modified carbodiimidoamine (X-1α)
To a flask equipped with a stirrer, a thermometer, and a reflux condenser, 190 parts of jER828 (trade name, manufactured by Mitsubishi Chemical Corporation, epoxy resin, epoxy equivalent 190, number average molecular weight 370), 59 parts of isopropylamine, 225 of isobutyl methyl ketone 225 Part was added, the temperature was raised to 120 ° C., and the reaction was continued until the total of epoxy-amine value was 2.22 meq / g or less. Next, 25 parts of ethylene glycol monobutyl ether and 126 parts of diisopropylcarbodiimide were added and reacted at 95 ° C. As a result of IR measurement, it was confirmed that absorption due to carbodiimide at 2120 cm ⁻¹ was almost eliminated. Isobutyl methyl ketone was added to adjust the solid content to obtain a carbodiimide amine-modified (X-1α) solution having a solid content of 50%.

Comparative Example 3 Modified carbodiimide amine (X-1β)
To a flask equipped with a stirrer, a thermometer, and a reflux condenser, 126 parts of diisopropylcarbodiimide, 59 parts of isopropylamine, and 275 parts of t-butanol were added, and the reaction was performed while heating under reflux. As a result of IR measurement, it was confirmed that absorption due to carbodiimide at 2120 cm ⁻¹ was almost eliminated.
Subsequently, 190 parts of jER828 (trade name, manufactured by Mitsubishi Chemical Corporation, epoxy resin, epoxy equivalent 190, number average molecular weight 370) are added, the reaction is carried out while heating under reflux, and the total epoxy amine value is 2.80 meq / g. The reaction was continued until:
After removing t-butanol under reduced pressure, ethylene glycol monobutyl ether was added to adjust the solid content to obtain a carbodiimide amine-modified (X-1β) solution having a solid content of 50%.

Comparative Example 4 Modified carbodiimide amine (X-2γ)
To a flask equipped with a stirrer, a thermometer, and a reflux condenser, 206 parts of dicyclohexylcarbodiimide, 99 parts of cyclohexylamine, and 550 parts of t-butanol were added, and the reaction was performed while heating under reflux. As a result of IR measurement, it was confirmed that absorption due to carbodiimide at 2120 cm ⁻¹ was almost eliminated. After removing t-butanol under reduced pressure, ethylene glycol monobutyl ether was added to adjust the solid content to obtain a carbodiimide amine-modified (X-2γ) solution having a solid content of 50%.

Comparative Example 5 Modified Carbodiimideamine (X-2α)
To a flask equipped with a stirrer, a thermometer, and a reflux condenser, jER828 (trade name, manufactured by Mitsubishi Chemical Corporation, epoxy resin, epoxy equivalent 190, number average molecular weight 370) 190 parts, cyclohexylamine 99 parts, isobutyl methyl ketone 225 Part was added, the temperature was raised to 120 ° C., and the reaction was continued until the total of the epoxy-amine value was 2.04 meq / g or less. Next, 25 parts of ethylene glycol monobutyl ether and 206 parts of dicyclohexylcarbodiimide were added and reacted at 95 ° C. As a result of IR measurement, it was confirmed that absorption due to carbodiimide at 2120 cm ⁻¹ was almost eliminated. Isobutyl methyl ketone was added to adjust the solid content to obtain a carbodiimide amine-modified (X-2α) solution having a solid content of 50%.

Comparative Example 6 Modified Carbodiimideamine (X-2β)
To a flask equipped with a stirrer, a thermometer, and a reflux condenser, 206 parts of dicyclohexylcarbodiimide, 99 parts of cyclohexylamine, and 550 parts of t-butanol were added, and the reaction was performed while heating under reflux. As a result of IR measurement, it was confirmed that absorption due to carbodiimide at 2120 cm ⁻¹ was almost eliminated.
Next, 190 parts of jER828 (trade name, manufactured by Mitsubishi Chemical Co., Ltd., epoxy resin, epoxy equivalent 190, number average molecular weight 370) are added, the reaction is carried out while heating under reflux, and the total epoxy amine value is 1.00 meq / g. The reaction was continued until:
After removing t-butanol under reduced pressure, ethylene glycol monobutyl ether was added to adjust the solid content to obtain a carbodiimide amine-modified (X-2β) solution having a solid content of 50%.

Comparative Example 7 Modified carbodiimide amine (X-3γ)
To a flask equipped with a stirrer, thermometer, and reflux condenser, 206 parts of dicyclohexylcarbodiimide, 115 parts of 1,1,3,3-tetramethylguanidine, and 36 parts of t-butanol were added, and the reaction was conducted while heating under reflux. It was. As a result of IR measurement, it was confirmed that absorption due to carbodiimide at 2120 cm ⁻¹ was almost eliminated. After removing t-butanol under reduced pressure, ethylene glycol monobutyl ether was added to adjust the solid content to obtain a carbodiimide amine-modified (X-3γ) solution having a solid content of 50%.

Example 1 Modified carbodiimide amine (X-3β)
To a flask equipped with a stirrer, thermometer, and reflux condenser, 206 parts of dicyclohexylcarbodiimide, 115 parts of 1,1,3,3-tetramethylguanidine and 36 parts of t-butanol were added, and the reaction was carried out while heating under reflux. It was. As a result of IR measurement, it was confirmed that absorption due to carbodiimide at 2120 cm ⁻¹ was almost eliminated.
Next, 190 parts of jER828 (trade name, manufactured by Mitsubishi Chemical Co., Ltd., epoxy resin, epoxy equivalent 190, number average molecular weight 370) are added and the reaction is carried out while heating under reflux. The total epoxy amine value is 1.92 meq / g. The reaction was continued until:
After removing t-butanol under reduced pressure, ethylene glycol monobutyl ether was added to adjust the solid content to obtain a carbodiimide amine modified product (X-3β) solution having a solid content of 50%.

Comparative Example 8 Modified carbodiimide amine (X-4γ)
To a flask equipped with a stirrer, a thermometer, and a reflux condenser, 126 parts of diisopropylcarbodiimide, 88 parts of N, N-dimethylethylenediamine and 54 parts of t-butanol were added, and the reaction was conducted while heating under reflux. As a result of IR measurement, it was confirmed that absorption due to carbodiimide at 2120 cm ⁻¹ was almost eliminated. After removing t-butanol under reduced pressure, ethylene glycol monobutyl ether was added to adjust the solid content to obtain a carbodiimide amine-modified (X-4γ) solution having a solid content of 50%.

Example 2 Modified carbodiimide amine (X-4α)
To a flask equipped with a stirrer, a thermometer, and a reflux condenser, 190 parts of jER828 (trade name, manufactured by Mitsubishi Chemical Corporation, epoxy resin, epoxy equivalent 190, number average molecular weight 370), ketimine block body 156 of N-methylethylenediamine And 225 parts of isobutyl methyl ketone were added, the temperature was raised to 120 ° C., and the reaction was continued until the total of the epoxy amine value (including ketimine block) was 3.59 meq / g or less. Next, 25 parts of ethylene glycol monobutyl ether, 18 parts of deionized water, and 126 parts of diisopropylcarbodiimide were added and reacted at 95 ° C. As a result of IR measurement, it was confirmed that absorption due to carbodiimide at 2120 cm ⁻¹ was almost eliminated. Isobutyl methyl ketone was added to adjust the solid content to obtain a carbodiimide amine-modified (X-4α) solution having a solid content of 50%.

Example 3 Modified carbodiimide amine (X-4β)
To a flask equipped with a stirrer, a thermometer, and a reflux condenser, 126 parts of diisopropylcarbodiimide, 102 parts of N, N, N′-trimethylethylenediamine and 54 parts of t-butanol were added, and the reaction was conducted while heating under reflux. As a result of IR measurement, it was confirmed that absorption due to carbodiimide at 2120 cm ⁻¹ was almost eliminated.
Next, 190 parts of jER828 (trade name, manufactured by Mitsubishi Chemical Corporation, epoxy resin, epoxy equivalent 190, number average molecular weight 370) are added, the reaction is carried out while heating under reflux, and the total epoxy amine value is 4.34 meq / g. The reaction was continued until:
After removing t-butanol under reduced pressure, ethylene glycol monobutyl ether was added to adjust the solid content to obtain a carbodiimide amine-modified (X-4β) solution having a solid content of 50%.

Comparative Example 9 Modified carbodiimide amine (X-5γ)
To a flask equipped with a stirrer, a thermometer, and a reflux condenser, 206 parts of dicyclohexylcarbodiimide, 88 parts of N, N-dimethylethylenediamine and 74 parts of t-butanol were added, and the reaction was conducted while heating under reflux. As a result of IR measurement, it was confirmed that absorption due to carbodiimide at 2120 cm ⁻¹ was almost eliminated. After removing t-butanol under reduced pressure, ethylene glycol monobutyl ether was added to adjust the solid content to obtain a carbodiimide amine-modified (X-5γ) solution having a solid content of 50%.

Example 4 Modified carbodiimide amine (X-5α)
To a flask equipped with a stirrer, a thermometer, and a reflux condenser, 190 parts of jER828 (trade name, manufactured by Mitsubishi Chemical Corporation, epoxy resin, epoxy equivalent 190, number average molecular weight 370), ketimine block body 156 of N-methylethylenediamine And 177 parts of isobutyl methyl ketone were added, the temperature was raised to 120 ° C., and the reaction was continued until the total of the epoxy-amine value (including ketimine block) was 3.92 meq / g or less.
Next, 25 parts of ethylene glycol monobutyl ether, 18 parts of deionized water, and 206 parts of dicyclohexylcarbodiimide were added and reacted at 95 ° C. As a result of IR measurement, it was confirmed that absorption due to carbodiimide at 2120 cm ⁻¹ was almost eliminated. Isobutyl methyl ketone was added to adjust the solid content to obtain a carbodiimide amine-modified (X-5α) solution having a solid content of 50%.

Example 5 Modified carbodiimide amine (X-5β)
To a flask equipped with a stirrer, a thermometer, and a reflux condenser, 206 parts of dicyclohexylcarbodiimide, 102 parts of N, N, N′-trimethylethylenediamine, and 74 parts of t-butanol were added, and the reaction was conducted while heating under reflux. As a result of IR measurement, it was confirmed that absorption due to carbodiimide at 2120 cm ⁻¹ was almost eliminated.
Next, 190 parts of jER828 (trade name, manufactured by Mitsubishi Chemical Corporation, epoxy resin, epoxy equivalent 190, number average molecular weight 370) was added, the reaction was conducted while heating under reflux, and the total epoxy amine value was 3.58 meq / g. The reaction was continued until:
After removing t-butanol under reduced pressure, ethylene glycol monobutyl ether was added to adjust the solid content to obtain a carbodiimide amine-modified (X-5β) solution having a solid content of 50%.

Comparative Example 10 Modified Carbodiimideamine (X-6γ)
To a flask equipped with a stirrer, thermometer, and reflux condenser, 252 parts of diisopropylcarbodiimide, 117 parts of N, N-bis (2-aminoethyl) methylamine, and 92 parts of t-butanol were added, and the reaction was conducted while heating under reflux. Went. As a result of IR measurement, it was confirmed that absorption due to carbodiimide at 2120 cm ⁻¹ was almost eliminated. After removing t-butanol under reduced pressure, ethylene glycol monobutyl ether was added to adjust the solid content to obtain a carbodiimide amine-modified (X-6γ) solution having a solid content of 50%.

Example 6 Modified carbodiimide amine (X-6α)
In a flask equipped with a stirrer, a thermometer, and a reflux condenser, jER828 (trade name, manufactured by Mitsubishi Chemical Corporation, epoxy resin, epoxy equivalent 190, number average molecular weight 370) 190 parts, diethylenetriamine ketimine block 267 parts, isobutyl 225 parts of methyl ketone was added, the temperature was raised to 120 ° C., and the reaction was continued until the total of the epoxy amine value (including the ketimine block) was 4.43 meq / g or less. Next, 25 parts of ethylene glycol monobutyl ether, 36 parts of deionized water, and 252 parts of diisopropylcarbodiimide were added and reacted at 95 ° C. As a result of IR measurement, it was confirmed that absorption due to carbodiimide at 2120 cm ⁻¹ was almost eliminated. Isobutyl methyl ketone was added to adjust the solid content to obtain a carbodiimide amine-modified (X-6α) solution having a solid content of 50%.

Example 7 Modified carbodiimide amine (X-6β)
To a flask equipped with a stirrer, thermometer, and reflux condenser, add 252 parts of diisopropylcarbodiimide, 165 parts of N, N-bis [2- (methylamino) ethyl] methylamine, and 92 parts of t-butanol, and heat to reflux. The reaction was carried out. As a result of IR measurement, it was confirmed that absorption due to carbodiimide at 2120 cm ⁻¹ was almost eliminated.
Next, 190 parts of jER828 (trade name, manufactured by Mitsubishi Chemical Co., Ltd., epoxy resin, epoxy equivalent 190, number average molecular weight 370) are added and the reaction is carried out while heating under reflux. The total epoxy amine value is 4.36 meq / g. The reaction was continued until:
After removing t-butanol under reduced pressure, ethylene glycol monobutyl ether was added to adjust the solid content to obtain a carbodiimide amine-modified (X-6β) solution having a solid content of 50%.

Comparative Example 11 Modified carbodiimide amine (X-7γ)
To a flask equipped with a stirrer, thermometer, and reflux condenser, 413 parts of dicyclohexylcarbodiimide, 117 parts of N, N-bis (2-aminoethyl) methylamine, and 133 parts of t-butanol were added, and the reaction was conducted while heating under reflux. Went. As a result of IR measurement, it was confirmed that absorption due to carbodiimide at 2120 cm ⁻¹ was almost eliminated. After removing t-butanol under reduced pressure, ethylene glycol monobutyl ether was added to adjust the solid content to obtain a carbodiimide amine-modified (X-7γ) solution having a solid content of 50%.

Example 8 Modified carbodiimide amine (X-7α1)
In a flask equipped with a stirrer, a thermometer, and a reflux condenser, jER828 (trade name, manufactured by Mitsubishi Chemical Corporation, epoxy resin, epoxy equivalent 190, number average molecular weight 370) 190 parts, diethylenetriamine ketimine block 267 parts, isobutyl 225 parts of methyl ketone was added, the temperature was raised to 120 ° C., and the reaction was continued until the total of the epoxy amine value (including the ketimine block) was 4.43 meq / g or less. Next, 25 parts of ethylene glycol monobutyl ether, 36 parts of deionized water, and 412 parts of dicyclohexylcarbodiimide were added and reacted at 95 ° C. As a result of IR measurement, it was confirmed that absorption due to carbodiimide at 2120 cm ⁻¹ was almost eliminated. Isobutyl methyl ketone was added to adjust the solid content to obtain a carbodiimide amine-modified (X-7α1) solution having a solid content of 50%.

Example 9 Modified carbodiimide amine (X-7α2)
To a flask equipped with a stirrer, a thermometer, and a reflux condenser, 475 parts of jER1001 (trade name, manufactured by Mitsubishi Chemical Corporation, epoxy resin, epoxy equivalent 475, number average molecular weight 900), 267 parts of a diethylenetriamine ketimine block, isobutyl 742 parts of methyl ketone was added, the temperature was raised to 120 ° C., and the reaction was continued until the total of the epoxy-amine value (including ketimine block) was 2.05 meq / g or less. Next, 25 parts of ethylene glycol monobutyl ether, 36 parts of deionized water, and 412 parts of dicyclohexylcarbodiimide were added and reacted at 95 ° C. As a result of IR measurement, it was confirmed that absorption due to carbodiimide at 2120 cm ⁻¹ was almost eliminated. Isobutyl methyl ketone was added to adjust the solid content to obtain a carbodiimide amine-modified (X-7α2) solution having a solid content of 50%.

Example 10 Modified carbodiimide amine (X-7β)
To a flask equipped with a stirrer, thermometer, and reflux condenser, 413 parts of dicyclohexylcarbodiimide, 165 parts of N, N-bis [2- (methylamino) ethyl] methylamine, and 133 parts of t-butanol were added and heated to reflux. The reaction was carried out. As a result of IR measurement, it was confirmed that absorption due to carbodiimide at 2120 cm ⁻¹ was almost eliminated.
Subsequently, 380 parts of jER828 (trade name, manufactured by Mitsubishi Chemical Co., Ltd., epoxy resin, epoxy equivalent 190, number average molecular weight 370) was added, and the reaction was carried out while heating under reflux. The total epoxy amine value was 2.84 meq / g. The reaction was continued until:
After removing t-butanol under reduced pressure, ethylene glycol monobutyl ether was added to adjust the solid content to obtain a carbodiimide amine-modified (X-7β) solution having a solid content of 50%.

Comparative Example 12 Modified amine (X-8)
In a flask equipped with a stirrer, a thermometer, and a reflux condenser, jER828 (trade name, manufactured by Mitsubishi Chemical Corporation, epoxy resin, epoxy equivalent 190, number average molecular weight 370) 190 parts, diethylenetriamine ketimine block 267 parts, isobutyl 225 parts of methyl ketone was added, the temperature was raised to 120 ° C., and the reaction was continued until the total of the epoxy amine value (including the ketimine block) was 4.43 meq / g or less. Next, 36 parts of deionized water and ethylene glycol monobutyl ether were added to adjust the solid content to obtain an amine-modified product (X-8) solution having a solid content of 50%.

Production of Pigment Dispersion Paste Production Example 4 Pigment Dispersion Paste A flask equipped with a stirrer, thermometer, dropping funnel and reflux condenser was charged with jER828 (trade name, manufactured by Mitsubishi Chemical Corporation, epoxy resin, epoxy equivalent 190, number average molecular weight 370). ) 1010 parts, 390 parts of bisphenol A, Plaxel 212 (trade name, polycaprolactone diol, Daicel Chemical Industries, Ltd., weight average molecular weight of about 1,250) 240 parts and 0.2 part of dimethylbenzylamine are added, and epoxy is added at 130 ° C. The reaction was continued until the equivalent was about 1,090. Next, 134 parts of dimethylethanolamine and 150 parts of a 90% aqueous lactic acid solution were added and reacted at 120 ° C. for 4 hours. Subsequently, methyl isobutyl ketone was added to adjust the solid content to obtain a resin solution for dispersing a quaternary ammonium salt pigment having a solid content of 60%.
Subsequently, 8.3 parts of the resin solution for pigment dispersion (5 parts of solid content), 14.5 parts of titanium oxide, 8.0 parts of purified clay, 0.3 part of carbon black, and 24.5 parts of propylene glycol monomethyl ether were added. In addition, the mixture was dispersed in a ball mill for 20 hours to obtain a pigment dispersion paste having a solid content of 50%.

Production of Thermosetting Paint (P) Comparative Example 13 Thermosetting Paint (P-1)
58.3 parts (solid content 35 parts) of the acrylic resin (Y-1) solution obtained in Production Example 1 and 58.3 parts (solid content) of the epoxy resin (Y-2) solution obtained in Production Example 2 35 parts), 42.9 parts of the blocked polyisocyanate curing agent (Z-1) obtained in Production Example 3 (solid content 30 parts), carbodiimide amine modified product (X-1γ) 5.4 parts (solid content) 2.8 parts, 0.015 mol per 100 parts of resin solid content) and uniformly stirred, and further added propylene glycol monomethyl ether to give a thermosetting paint (P-1) with a solid content of 50%. Manufactured.

Examples 11 to 20 and Comparative Examples 14 to 26 Thermosetting paints (P-2) to (P-24)
Production of thermosetting paints (P-2) to (P-24) having a solid content of 50% in the same manner as in Comparative Example 13 except that the modified carbodiimide amine (X) is changed to that shown in Table 3 below. did.
In addition, 0.015 mol of carbodiimide amine modified product (X) was blended with respect to 100 parts of resin solid content. Regarding the thermosetting paint (P) containing the carbodiimide amine-modified product (X) to which the epoxy resin (EP1 or EP2) is added, the solid mass of the epoxy resin (Y-2) and the solid content of the epoxy resin (EP1 or EP2) The epoxy resin (Y-2) was blended so that the total mass was 35 parts.

Production of Thermosetting Paint (Q) Comparative Example 27 Thermosetting Paint (Q-1)
50 parts (solid content 30 parts) of the acrylic resin (Y-1) solution obtained in Production Example 1 and 58.3 parts (solid content 35 parts) of the epoxy resin (Y-2) solution obtained in Production Example 2 ), 42.9 parts (solid content 30 parts) of the blocked polyisocyanate curing agent (Z-1) obtained in Production Example 3, and 55.6 parts (solid content) of the pigment dispersion paste obtained in Production Example 4. 27.8 parts, resin solid content 5 parts), carbodiimide amine modified product (X-1γ) 5.4 parts (solid content 2.8 parts, 0.015 mol with respect to resin solid content 100 parts) and uniform And propylene glycol monomethyl ether was further added to produce a thermosetting paint (Q-1) having a solid content of 50%.

Examples 21 to 30 and Comparative Examples 28 to 40 Thermosetting paints (Q-2) to (Q-24)
Production of thermosetting paints (Q-2) to (Q-24) having a solid content of 50% in the same manner as in Comparative Example 27 except that the modified carbodiimide amine (X) is changed to that shown in Table 4 below. did.
In addition, 0.015 mol of carbodiimide amine modified product (X) was blended with respect to 100 parts of resin solid content. Regarding the thermosetting paint (Q) containing the modified carbodiimide amine (X) to which the epoxy resin (EP1 or EP2) is added, the solid content of the epoxy resin (Y-2) and the solid content of the epoxy resin (EP1 or EP2) The epoxy resin (Y-2) was blended so that the total mass was 35 parts.

Tables 3 and 4 below show the results of evaluation tests [curability (gel fraction), water resistance (gloss retention), 80 ° C. hot water resistance (gloss retention)] conducted by the methods described below.

Evaluation test <Curing property (gel fraction)>
The glass plate is coated with the thermosetting paint (P) of the example or the comparative example on the glass plate using an applicator so that the cured film thickness is about 30 μm, and is heated and cured at a temperature of 140 ° C. for 30 minutes. The coating film was peeled off. Next, the coating film put in the wire mesh was placed in a separate type round bottom flask, 100 g of acetone was added to 1 g of the coating film, and the mixture was refluxed for 5 hours. The taken-out coating film was dried at 105 ° C. for 1 hour, the coating film weight was measured, and the gel fraction was calculated by the following formula.
Gel fraction (%) = weight of coating film after reflux / weight of coating film before reflux × 100
The evaluation was performed according to the following criteria. S to C are acceptable and D is unacceptable.
S: The gel fraction is 95% or more, and the curability is very excellent.
A: The gel fraction is 90% or more and less than 95%, and the curability is somewhat excellent.
B: The gel fraction is 80% or more and less than 90%, and the curability is excellent.
C: The gel fraction is 70% or more and less than 80%, and the curability is normal.
D: The gel fraction is less than 70% and the curability is inferior.

<Water resistance (gloss retention)>
Cold-rolled steel sheet (size 400 x 300 x 0.8 mm) treated with "Palbond # 3020" (Nihon Parkerizing Co., Ltd., zinc phosphate treatment) was added to "Electron GT-10" (Kansai Paint Co., Ltd., thermosetting Epoxy resin-based cationic electrodeposition paint) is electrodeposited to a film thickness of 20 μm, cured by heating at 170 ° C. for 30 minutes, and “TP-65” (trade name, manufactured by Kansai Paint Co., Ltd.) Polyester / melamine resin-based automotive intermediate coating) was air spray coated to a dry film thickness of 35 μm and cured by heating at 140 ° C. for 30 minutes.
Next, the thermosetting paint (Q) of the example or comparative example was applied thereon using an applicator so as to have a cured coating film thickness of about 20 μm, and was cured by heating at a temperature of 140 ° C. for 30 minutes.
The obtained test plate was immersed in pure water and allowed to stand at 40 ° C. for 240 hours, and the glossiness after immersion was measured to calculate the gloss retention.
The gloss retention is calculated by the following formula based on the value obtained by measuring the surface (test surface) according to JIS Z 8741-1997 and the specular gloss at an incident angle of 60 degrees. is there.
Gloss retention (%) = (Glossiness after water resistance test / initial glossiness) × 100
The evaluation was performed according to the following criteria. S to C are acceptable and D is unacceptable.
S: The gloss retention is 95% or more, and the water resistance is very excellent.
A: The gloss retention is 90% or more and less than 95%, and the water resistance is slightly superior.
B: The gloss retention is 80% or more and less than 90%, and the water resistance is excellent.
C: Gloss retention is 70% or more and less than 80%, and water resistance is normal.
D: Gloss retention is less than 70% and water resistance is inferior.

<80 ° C warm water resistance (gloss retention)>
A test plate obtained in the same manner as in the water resistance test was immersed in pure water at a temperature of 80 ° C. and allowed to stand for 240 hours, and the gloss retention after the immersion was measured to calculate the gloss retention.
The gloss retention is calculated by the following formula based on the value obtained by measuring the surface (test surface) according to JIS Z 8741-1997 and the specular gloss at an incident angle of 60 degrees. is there.
Gloss retention (%) = (Glossiness after water resistance test / initial glossiness) × 100
The evaluation was performed according to the following criteria. S to C are acceptable and D is unacceptable.
S: The gloss retention is 95% or more, and the 80 ° C. warm water resistance is very excellent.
A: The gloss retention is 90% or more and less than 95%, and the 80 ° C. warm water resistance is slightly superior.
B: The gloss retention is 80% or more and less than 90%, and the 80 ° C. warm water resistance is excellent.
C: Gloss retention is 70% or more and less than 80%, and 80 ° C. hot water resistance is normal.
D: Gloss retention is less than 70%, and 80 ° C. warm water resistance is poor.

Although the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. This application is based on a Japanese patent application filed on November 24, 2016 (Japanese Patent Application No. 2016-228375), the contents of which are incorporated herein by reference.

Claims (6)

1. A method for producing a modified carbodiimide amine (X) by the following method [α] or method [β].
   [Α] An amine compound (A) having two or more nitrogen atoms represented by the following formula (1) is reacted with a compound (B) having a number average molecular weight of 300 or more, and then a carbodiimide compound (C) is reacted to form a carbodiimide. An amine-modified product (X) is obtained.
   [Β] An amine compound (A) having two or more nitrogen atoms represented by the following formula (1) is reacted with a carbodiimide compound (C), and then a compound (B) having a number average molecular weight of 300 or more is reacted to react with the carbodiimide. An amine-modified product (X) is obtained.
   

   

   [In Formula (1), R ¹ to R ⁴ are each independently a hydrogen atom or an organic group having 1 or more carbon atoms, and the organic group is selected from the group consisting of an oxygen atom, a nitrogen atom, a sulfur atom, and a halogen atom. May contain one or more atoms. X is an organic group having 1 or more carbon atoms, and the organic group may contain one or more atoms selected from the group consisting of an oxygen atom, a nitrogen atom, a sulfur atom, and a halogen atom. n is an integer of 1 to 3. ]
2. The production method according to claim 1, wherein the amine compound (A) is a compound represented by the following formula (1-1).
   

   

   [In the formula ^(1-1), the definition of R ^1, R 2, ^{R 4} have the same meanings as ^{R 1,} R 2, ^{R 4} of formula (1). R ³¹ and R ³² have the same meaning as R ^{3 in} formula (1). m is an integer of 0 to 3. p and q are each independently an integer of 1 to 6. ]
3. The production method according to claim 1, wherein X of the amine compound (A) has a structure represented by the following formula (3).
   

   

   [In Formula (3), Y is a hydrogen atom or an organic group having 1 or more carbon atoms, and the organic group may include one or more atoms selected from the group consisting of an oxygen atom, a nitrogen atom, a sulfur atom, and a halogen atom. Good. * Is a bond. ]
4. The production method according to any one of claims 1 to 3, wherein the carbodiimide compound (C) is a compound represented by the following formula (2).
   R ⁵ -N = C = N-R ⁶ (2)
   [In Formula (2), R ⁵ and R ⁶ are each independently an organic group having 1 or more carbon atoms, and the organic group is one or more selected from the group consisting of an oxygen atom, a nitrogen atom, a sulfur atom, and a halogen atom. May be included. ]
5. A carbodiimide amine-modified product (X) obtained by the production method according to any one of claims 1 to 4, a hydroxyl group-containing resin (Y), and a blocked polyisocyanate curing agent (Z) are mixed to be thermosetting. A method for producing a thermosetting coating composition, which obtains a coating composition.
6. A method for producing a coated article, wherein a coated article is obtained by applying a thermosetting coating composition obtained by the production method according to claim 5 onto an article to be coated.