JP5759033B2 - Curing agent, adhesive using the same, and paint - Google Patents

Description

  The present invention relates to a curing agent. More specifically, the present invention relates to a curing agent for reacting with and curing the main agent in the adhesive, and a curing agent that can be suitably used as a curing agent for reacting with and curing the main agent in the paint.

In recent years, water-based resins with little environmental pollution have been widely studied and adopted in the fields of paints, adhesives, coating agents, and the like. On the other hand, organic solvent-based resins are also widely used due to technical problems and economic reasons.
Generally, a water-based resin or a solvent-based resin alone has insufficient solvent resistance, chemical resistance, water resistance, weather resistance, heat resistance, adhesiveness, and the like, so that various physical properties are improved using a curing agent. Means are widely used.

For example, a water-dispersible polyisocyanate composition in which a reaction product of an ethylene oxide unit and an aliphatic polyisocyanate is emulsified as a curing agent for a carboxyl group-containing water-based resin with little environmental pollution, in order to make crosslinkability and emulsification performance parallel. (Patent Document 1), an easily emulsifiable surface active polycarbodiimide containing a polyalkylene oxide residue of a surface active component in the molecular structure (Patent Document 2), and a self-emulsifiable polyethylene glycol unit bonded via a urethane bond A polycarbodiimide compound (Patent Document 3) and the like have been proposed.
However, although the composition proposed in Patent Document 1 is dispersible in water, it contains an isocyanate group, so that the pot life is short and there is a problem in practicality.
In addition, the polycarbodiimides proposed in Patent Documents 2 and 3 are polycarbodiimides having a linear structure, and contain high molecular weight polyalkylene oxide residues or polyethylene glycol residues in the molecular structure. There's a problem.

That is, in order to realize sufficient curing characteristics, it is necessary to increase the amount of carbodiimide group, but this increases the molecular weight and rigidity of the curing agent, thereby reducing the solubility and dispersibility in water or solvent. A problem may occur in workability such as a water dispersion process.
Furthermore, an increase in the molecular weight of the curing agent decreases the crosslink density of the resin, which may cause problems with the solvent resistance, chemical resistance, water resistance, weather resistance, heat resistance, adhesion, etc. of the cured resin.
It has also been proposed to solve the problem of dispersion of the cross-linked resin and the curing agent by incorporating a carbodiimide group and a surface active component into an aqueous polymer main ingredient containing an anionic hydrophilic group, specifically a carboxyl group. However (for example, Patent Document 4) is not an effective solution for preventing a decrease in crosslink density.

JP 61-291613 A JP 63-264128 A Japanese Patent Laid-Open No. 10-060272 JP 2005-15734 A

  An object of the present invention is to provide a curing agent capable of solving the problems of the prior art and efficiently curing a water-based resin or an organic solvent-based resin containing a carboxyl group.

  The present inventor has intensively studied to solve the above problems, and a curing agent containing a carbodiimide compound having a specific structure as a curing component efficiently cures a carboxyl group-containing resin, and has solvent resistance and chemical resistance. The present inventors have found that a cured resin having improved water resistance, weather resistance, heat resistance, adhesiveness, and the like can be obtained, and the present invention has been achieved.

That is, the object of the present invention is to
Represented by the following general formula, that the ring structure is achieved by hardening agent containing only free surfactant containing carbodiimide groups (C) as a curing component a carbodiimide compound (B) is 8-50 membered ring it can.

（式中、Ｑは、脂肪族基、脂環族基、芳香族基またはこれらの組み合わせである２〜４価の結合基であり、ヘテロ原子、置換基を含んでいてもよい。）

(In the formula, Q is a divalent to tetravalent linking group that is an aliphatic group, an alicyclic group, an aromatic group, or a combination thereof, and may contain a hetero atom or a substituent.)

ADVANTAGE OF THE INVENTION According to this invention, the hardening | curing agent which can harden the water-system resin and organic solvent resin which contain a carboxyl group can be provided.
In addition, the carboxyl group-containing resin (cured product) cured by the curing agent of the present invention is excellent in solvent resistance, chemical resistance, water resistance, weather resistance, heat resistance, adhesiveness, and the like. The composition of the resin (before curing) and the curing agent can be suitably used as a paint or an adhesive.

  The hardening | curing agent of this invention is represented by the following general formula, and contains the carbodiimide compound (B) whose ring structure is an 8-50 membered ring as a hardening component.

（式中、Ｑは、脂肪族基、脂環族基、芳香族基またはこれらの組み合わせである２〜４価の結合基であり、ヘテロ原子、置換基を含んでいてもよい。）

(In the formula, Q is a divalent to tetravalent linking group that is an aliphatic group, an alicyclic group, an aromatic group, or a combination thereof, and may contain a hetero atom or a substituent.)

By containing the carbodiimide compound (B) as a curing component, the carboxyl group-containing resin to be cured can be efficiently cured, improving solvent resistance, chemical resistance, water resistance, weather resistance, heat resistance, adhesion, etc. Cured product and coating film can be provided.
Here, the carbodiimide compound (B) forms a cyclic structure in which a carbodiimide group (—N═C═N—)) is contained in the ring, and has one carbodiimide group in the ring structure. Mononitrogen and secondary nitrogen are bound by a linking group.
When one molecule has a plurality of ring structures, it is sufficient that at least one ring structure includes a carbodiimide group, but the plurality of ring structures include one carbodiimide group. May be.

From the viewpoint of the crosslinking efficiency of the curing agent of the present invention, the heat resistance of the resulting resin (cured product), and the durability to moisture, the ring structure in the carbodiimide compound (B) must be formed of an 8- to 50-membered ring. It is. When it is smaller than the 8-membered ring, the stability of the cyclic structure is poor, and when it is used as a curing agent, the cross-linking of the carboxyl group-containing resin may not proceed favorably. The difference between the carbodiimide compound having a carbodiimide compound and the carbodiimide compound (B) of the present invention is reduced, and the significance of the present invention may be lost. It may be difficult to form a uniform emulsion with the resin.
In this respect, the ring is more preferably a 10 to 30 membered ring, further preferably a 10 to 20 membered ring, and particularly preferably a 10 to 15 membered ring.

The molecular weight of the carbodiimide compound (B) is preferably 100 to 1,000. If it is lower than 100, the structure stability and volatility of the carbodiimide compound (B) may be problematic. On the other hand, if it is higher than 1,000, the production of the carbodiimide compound (B) may require synthesis in a dilution system or the yield may be reduced, which may cause a problem in cost.
From this viewpoint, the molecular weight of the carbodiimide compound (B) is more preferably 100 to 750, and further preferably 250 to 750.

Next, Q in the annular structure will be described.
The general formula, Q, is a divalent to tetravalent linking group that is an aliphatic group, an alicyclic group, an aromatic group, or a combination thereof, and may contain a hetero atom or a substituent.
Two of the valences of this linking group are used to form a cyclic structure. When Q is a trivalent or tetravalent linking group, it is bonded to a polymer or other cyclic structure via a single bond, a double bond, an atom, or an atomic group.

The linking group is a divalent to tetravalent C 1-20 aliphatic group, a divalent to tetravalent C 3-20 alicyclic group, a divalent to tetravalent C 5-15 aromatic group, or A combination of these is preferred. As the linking group, one having the necessary number of carbon atoms for forming a cyclic structure is selected. Examples of combinations include structures such as an alkylene-arylene group in which an alkylene group and an arylene group are bonded.
The aliphatic group, alicyclic group, and aromatic group constituting the bonding group may each include a hetero atom and a substituent. A hetero atom refers to O, N, S, P. Examples of the substituent include an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 15 carbon atoms, a halogen atom, a nitro group, an amide group, a hydroxyl group, an ester group, an ether group, and an aldehyde group.

In the present invention, examples of the halogen atom include a chlorine atom, a bromine atom, and an iodine atom.
The linking group (Q) is preferably a divalent to tetravalent linking group represented by the following formula (i-1), (i-2) or (i-3).

In the formula, Ar ¹ and Ar ² are each independently a divalent to tetravalent aromatic group having 5 to 15 carbon atoms, and may contain a hetero atom or a substituent.
Examples of the aromatic group include an arylene group having 5 to 15 carbon atoms, an arenetriyl group having 5 to 15 carbon atoms, and an arenetetrayl group having 5 to 15 carbon atoms. Examples of the arylene group (divalent) include a phenylene group and a naphthalenediyl group. Examples of the arenetriyl group (trivalent) include a benzenetriyl group and a naphthalenetriyl group. Examples of the arenetetrayl group (tetravalent) include a benzenetetrayl group and a naphthalenetetrayl group.

These aromatic groups may be substituted. Examples of the substituent include an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 15 carbon atoms, a halogen atom, a nitro group, an amide group, a hydroxyl group, an ester group, an ether group, and an aldehyde group. These aromatic groups may contain a hetero atom and have a heterocyclic structure. Heteroatoms include O, N, S, and P.
R ¹ and R ² are each independently a divalent to tetravalent aliphatic group having 1 to 20 carbon atoms, a divalent to tetravalent carbon group having 3 to 20 alicyclic groups, a combination thereof, or an aliphatic group thereof. , A combination of an alicyclic group and a divalent to tetravalent aromatic group having 5 to 15 carbon atoms, and may contain a hetero atom or a substituent.

Examples of the aliphatic group include an alkylene group having 1 to 20 carbon atoms, an alkanetriyl group having 1 to 20 carbon atoms, and an alkanetetrayl group having 1 to 20 carbon atoms. Examples of the alkylene group include a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group, a heptylene group, an octylene group, a nonylene group, a decylene group, a dodecylene group, and a hexadecylene group. As the alkanetriyl group, methanetriyl group, ethanetriyl group, propanetriyl group, butanetriyl group, pentanetriyl group, hexanetriyl group, heptanetriyl group, octanetriyl group, nonanetriyl group, decantriyl group, dodecantriyl group, Examples include a hexadecantriyl group. As alkanetetrayl group, methanetetrayl group, ethanetetrayl group, propanetetrayl group, butanetetrayl group, pentanetetrayl group, hexanetetrayl group, heptanetetrayl group, octanetetrayl group, nonanetetrayl group Decanetetrayl group, dodecanetetrayl group, hexadecanetetrayl group and the like.
These aliphatic groups may be substituted. Examples of the substituent include an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 15 carbon atoms, a halogen atom, a nitro group, an amide group, a hydroxyl group, an ester group, an ether group, and an aldehyde group. Moreover, these aliphatic groups may contain a hetero atom. Heteroatoms include O, N, S, and P.

Examples of the alicyclic group include a cycloalkylene group having 3 to 20 carbon atoms, a cycloalkanetriyl group having 3 to 20 carbon atoms, and a cycloalkanetetrayl group having 3 to 20 carbon atoms. Examples of the cycloalkylene group include a cyclopropylene group, a cyclobutylene group, a cyclopentylene group, a cyclohexylene group, a cycloheptylene group, a cyclooctylene group, a cyclononylene group, a cyclodecylene group, a cyclododecylene group, and a cyclohexadecylene group. As cycloalkanetriyl group, cyclopropanetriyl group, cyclobutanetriyl group, cyclopentanetriyl group, cyclohexanetriyl group, cycloheptanetriyl group, cyclooctanetriyl group, cyclononanetriyl group, cyclodecanetriyl group Group, cyclododecane triyl group, cyclohexadecane triyl group and the like. As cycloalkanetetrayl group, cyclopropanetetrayl group, cyclobutanetetrayl group, cyclopentanetetrayl group, cyclohexanetetrayl group, cycloheptanetetrayl group, cyclooctanetetrayl group, cyclononanetetrayl group, cyclodecanetetrayl group Yl group, cyclododecanetetrayl group, cyclohexadecanetetrayl group and the like.
These alicyclic groups may be substituted. Examples of the substituent include an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 15 carbon atoms, a halogen atom, a nitro group, an amide group, a hydroxyl group, an ester group, an ether group, and an aldehyde group. Moreover, these alicyclic groups may include a hetero atom and have a heterocyclic structure. Heteroatoms include O, N, S, and P.

Examples of the aromatic group include an arylene group having 5 to 15 carbon atoms, an arenetriyl group having 5 to 15 carbon atoms, and an arenetetrayl group having 5 to 15 carbon atoms. Examples of the arylene group include a phenylene group and a naphthalenediyl group. Examples of the arenetriyl group (trivalent) include a benzenetriyl group and a naphthalenetriyl group. Examples of the arenetetrayl group (tetravalent) include a benzenetetrayl group and a naphthalenetetrayl group.
These aromatic groups may be substituted. Examples of the substituent include an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 15 carbon atoms, a halogen atom, a nitro group, an amide group, a hydroxyl group, an ester group, an ether group, and an aldehyde group.
Moreover, these aromatic groups may include a hetero atom and have a heterocyclic structure. Heteroatoms include O, N, S, and P.
X ¹ and X ² are each independently a 2 to 4 valent aliphatic group having 1 to 20 carbon atoms, a 2 to 4 valent alicyclic group having 3 to 20 carbon atoms, and a 2 to 4 valent carbon number having 5 to 5 carbon atoms. 15 aromatic groups, or a combination thereof, which may contain heteroatoms and substituents.

Examples of the aliphatic group include an alkylene group having 1 to 20 carbon atoms, an alkanetriyl group having 1 to 20 carbon atoms, and an alkanetetrayl group having 1 to 20 carbon atoms. Examples of the alkylene group include a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group, a heptylene group, an octylene group, a nonylene group, a decylene group, a dodecylene group, and a hexadecylene group. As the alkanetriyl group, methanetriyl group, ethanetriyl group, propanetriyl group, butanetriyl group, pentanetriyl group, hexanetriyl group, heptanetriyl group, octanetriyl group, nonanetriyl group, decantriyl group, dodecantriyl group, Examples include a hexadecantriyl group. As alkanetetrayl group, methanetetrayl group, ethanetetrayl group, propanetetrayl group, butanetetrayl group, pentanetetrayl group, hexanetetrayl group, heptanetetrayl group, octanetetrayl group, nonanetetrayl group Decanetetrayl group, dodecanetetrayl group, hexadecanetetrayl group and the like.
These aliphatic groups may be substituted. Examples of the substituent include an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 15 carbon atoms, a halogen atom, a nitro group, an amide group, a hydroxyl group, an ester group, an ether group, and an aldehyde group. Moreover, these aliphatic groups may contain a hetero atom. Heteroatoms include O, N, S, and P.

Examples of the alicyclic group include a cycloalkylene group having 3 to 20 carbon atoms, a cycloalkanetriyl group having 3 to 20 carbon atoms, and a cycloalkanetetrayl group having 3 to 20 carbon atoms. Examples of the cycloalkylene group include a cyclopropylene group, a cyclobutylene group, a cyclopentylene group, a cyclohexylene group, a cycloheptylene group, a cyclooctylene group, a cyclononylene group, a cyclodecylene group, a cyclododecylene group, and a cyclohexadecylene group. As the alkanetriyl group, cyclopropanetriyl group, cyclobutanetriyl group, cyclopentanetriyl group, cyclohexanetriyl group, cycloheptanetriyl group, cyclooctanetriyl group, cyclononanetriyl group, cyclodecanetriyl group , Cyclododecanetriyl group, cyclohexadecanetriyl group and the like. As the alkanetetrayl group, cyclopropanetetrayl group, cyclobutanetetrayl group, cyclopentanetetrayl group, cyclohexanetetrayl group, cycloheptanetetrayl group, cyclooctanetetrayl group, cyclononanetetrayl group, cyclodecanetetrayl group Group, cyclododecanetetrayl group, cyclohexadecanetetrayl group and the like.
These alicyclic groups may be substituted. Examples of the substituent include an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 15 carbon atoms, a halogen atom, a nitro group, an amide group, a hydroxyl group, an ester group, an ether group, and an aldehyde group. Moreover, these alicyclic groups may include a hetero atom and have a heterocyclic structure. Heteroatoms include O, N, S, and P.

Examples of the aromatic group include an arylene group having 5 to 15 carbon atoms, an arenetriyl group having 5 to 15 carbon atoms, and an arenetetrayl group having 5 to 15 carbon atoms. Examples of the arylene group include a phenylene group and a naphthalenediyl group. Examples of the arenetriyl group (trivalent) include a benzenetriyl group and a naphthalenetriyl group. Examples of the arenetetrayl group (tetravalent) include a benzenetetrayl group and a naphthalenetetrayl group.
These aromatic groups may be substituted. Examples of the substituent include an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 15 carbon atoms, a halogen atom, a nitro group, an amide group, a hydroxyl group, an ester group, an ether group, and an aldehyde group. Moreover, these aromatic groups may include a hetero atom and have a heterocyclic structure. Heteroatoms include O, N, S, and P.

s and k are each independently an integer of 0 to 10, preferably an integer of 0 to 3, more preferably an integer of 0 to 1. When s and k exceed 10, the cyclic carbodiimide compound is difficult to synthesize, and the cost may increase significantly. From this viewpoint, the integer is preferably selected in the range of 0 to 3. When s or k is 2 or more, X ¹ or X ² as a repeating unit may be different from other X ¹ or X ² .
X ³ is a 2 to 4 valent aliphatic group having 1 to 20 carbon atoms, a 2 to 4 valent alicyclic group having 3 to 20 carbon atoms, a 2 to 4 valent aromatic group having 5 to 15 carbon atoms, Or it is a combination of these and may contain a hetero atom and a substituent.

Examples of the aliphatic group include an alkylene group having 1 to 20 carbon atoms, an alkanetriyl group having 1 to 20 carbon atoms, and an alkanetetrayl group having 1 to 20 carbon atoms. Examples of the alkylene group include a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group, a heptylene group, an octylene group, a nonylene group, a decylene group, a dodecylene group, and a hexadecylene group. As the alkanetriyl group, methanetriyl group, ethanetriyl group, propanetriyl group, butanetriyl group, pentanetriyl group, hexanetriyl group, heptanetriyl group, octanetriyl group, nonanetriyl group, decantriyl group, dodecantriyl group, Examples include a hexadecantriyl group. As alkanetetrayl group, methanetetrayl group, ethanetetrayl group, propanetetrayl group, butanetetrayl group, pentanetetrayl group, hexanetetrayl group, heptanetetrayl group, octanetetrayl group, nonanetetrayl group Decanetetrayl group, dodecanetetrayl group, hexadecanetetrayl group and the like.
These aliphatic groups may contain a substituent, such as an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 15 carbon atoms, a halogen atom, a nitro group, an amide group, a hydroxyl group, or an ester group. , Ether group, aldehyde group and the like. Moreover, these aliphatic groups may contain a hetero atom. Heteroatoms include O, N, S, and P.

Examples of the alicyclic group include a cycloalkylene group having 3 to 20 carbon atoms, a cycloalkanetriyl group having 3 to 20 carbon atoms, and a cycloalkanetetrayl group having 3 to 20 carbon atoms. Examples of the cycloalkylene group include a cyclopropylene group, a cyclobutylene group, a cyclopentylene group, a cyclohexylene group, a cycloheptylene group, a cyclooctylene group, a cyclononylene group, a cyclodecylene group, a cyclododecylene group, and a cyclohexadecylene group. As the alkanetriyl group, cyclopropanetriyl group, cyclobutanetriyl group, cyclopentanetriyl group, cyclohexanetriyl group, cycloheptanetriyl group, cyclooctanetriyl group, cyclononanetriyl group, cyclodecanetriyl group , Cyclododecanetriyl group, cyclohexadecanetriyl group and the like. As the alkanetetrayl group, cyclopropanetetrayl group, cyclobutanetetrayl group, cyclopentanetetrayl group, cyclohexanetetrayl group, cycloheptanetetrayl group, cyclooctanetetrayl group, cyclononanetetrayl group, cyclodecanetetrayl group Group, cyclododecanetetrayl group, cyclohexadecanetetrayl group and the like.
These alicyclic groups may contain a substituent, such as an alkyl group having 1 to 20 carbon atoms, an arylene group having 6 to 15 carbon atoms, a halogen atom, a nitro group, an amide group, a hydroxyl group, and an ester. Group, ether group, aldehyde group and the like. Moreover, these alicyclic groups may include a hetero atom and have a heterocyclic structure. Heteroatoms include O, N, S, and P.

Examples of the aromatic group include an arylene group having 5 to 15 carbon atoms, an arenetriyl group having 5 to 15 carbon atoms, and an arenetetrayl group having 5 to 15 carbon atoms. Examples of the arylene group include a phenylene group and a naphthalenediyl group. Examples of the arenetriyl group (trivalent) include a benzenetriyl group and a naphthalenetriyl group. Examples of the arenetetrayl group (tetravalent) include a benzenetetrayl group and a naphthalenetetrayl group.
These aromatic groups may be substituted. Examples of the substituent include an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 15 carbon atoms, a halogen atom, a nitro group, an amide group, a hydroxyl group, an ester group, an ether group, and an aldehyde group. Moreover, these aromatic groups may include a hetero atom and have a heterocyclic structure. Heteroatoms include O, N, S, and P.

As described above, Ar ¹ , Ar ² , R ¹ , R ² , X ¹ , X ² and X ³ may contain a hetero atom.
When Q is a divalent linking group, Ar ¹ , Ar ² , R ¹ , R ² , X ¹ , X ² and X ³ are all divalent groups. When Q is a trivalent linking group, one of Ar ¹ , Ar ² , R ¹ , R ² , X ¹ , X ² and X ³ is a trivalent group. When Q is a tetravalent linking group, one of Ar ¹ , Ar ² , R ¹ , R ² , X ¹ , X ² and X ³ is a tetravalent group or two are trivalent It is a group.
Examples of the carbodiimide compound (B) of the present invention include the following compounds.

Such carbodiimide compounds (B) can be used alone or in combination of two or more as a curing component in the curing agent of the present invention.
From the viewpoint of the curing efficiency of the carboxyl group-containing resin, the solvent resistance, chemical resistance, water resistance, weather resistance, heat resistance, adhesiveness, etc. of the cured resin, the curing agent of the present invention contains carbodiimide per 100 parts by weight of the curing agent. The content of the compound (B) is 5 to 90 parts by weight, preferably 7 to 80 parts by weight, more preferably 10 to 70 parts by weight.

The curing agent containing the carbodiimide compound (B) of the present invention has a ring structure containing one carbodiimide group represented by “—N═C═N—” in one molecule from the viewpoint of crosslinking the resin. It is preferable to contain a plurality of carbodiimide compounds (hereinafter sometimes abbreviated as polyvalent cyclic carbodiimide compounds).
The valence of the polycyclic carbodiimide compound (the number of ring structures including one carbodiimide group present in the compound) is 2 to 4, more preferably 2 to 3, based on the balance between the production cost and the physical properties of the curing characteristics. It is.

Furthermore, from the same viewpoint, the content of the polycyclic carbodiimide compound is 1 to 90 wt%, more preferably 10 to 50 wt%, and still more preferably 20 to 50 wt% based on the total weight of the carbodiimide compound (B). .
In the present invention, examples of the polyvalent cyclic carbodiimide compound include the following compounds.

Such a polycyclic carbodiimide compound can be contained alone or in combination of two or more as a curing component in the curing agent of the present invention.
The method for producing the carbodiimide compound (B) and the polyvalent cyclic carbodiimide compound of the present invention is not particularly limited, and is suitably produced by modifying and combining conventionally known methods.
As such a production method, a method for producing an amine body via an isocyanate body, a method for producing an amine body via an isothiocyanate body, a method for producing an amine body via a triphenylphosphine body, an amine body A method for producing from a urea body via a urea body, a method for producing from an amine body via a thiourea body, a process for producing a carboxylic acid body via an isocyanate body, a method for producing a lactam body by induction, etc. Can be mentioned.

（２）得られたニトロ体を還元して下記式（ｄ）で表わされるアミン体を得る工程、

（３）得られたアミン体とトリフェニルホスフィンジブロミドを反応させ下記式（ｅ）で表されるトリフェニルホスフィン体を得る工程、および

（４）得られたトリフェニルホスフィン体を反応系中でイソシアネート化した後、直接脱炭酸させることによって製造したものは、本願発明に用いる環状カルボジイミド化合物として好適に用いることができる。 Depending on the compound to be produced, an appropriate production method may be employed. For example, (1) nitrophenols represented by the following formula (a-1), nitrophenols represented by the following formula (a-2) And a compound represented by the following formula (b) to obtain a nitro compound represented by the following formula (c),

(2) A step of reducing the obtained nitro body to obtain an amine body represented by the following formula (d);

(3) a step of reacting the obtained amine body with triphenylphosphine dibromide to obtain a triphenylphosphine body represented by the following formula (e); and

(4) After the obtained triphenylphosphine body is isocyanated in the reaction system and then directly decarboxylated, it can be suitably used as the cyclic carbodiimide compound used in the present invention.

(In the above formula, Ar ¹ and Ar ² are each independently an aromatic group optionally substituted with an alkyl group having 1 to 6 carbon atoms or a phenyl group. E ¹ and E ² are each independently a halogen atom. A group selected from the group consisting of an atom, a toluenesulfonyloxy group, a methanesulfonyloxy group, a benzenesulfonyloxy group, and a p-bromobenzenesulfonyloxy group, Ar _a is a phenyl group, and X is a group represented by the following formula (e -1) to (e-3).

（式中、ｎは１〜６の整数である。）

(In the formula, n is an integer of 1 to 6.)

（式中、ｍおよびｎは各々独立に０〜３の整数である。）

(In the formula, m and n are each independently an integer of 0 to 3.)

（式中、Ｒ^１およびＲ^２は各々独立に、炭素数１〜６のアルキル基、フェニル基を表す。）

(In the formula, R ¹ and R ² each independently represents an alkyl group having 1 to 6 carbon atoms or a phenyl group.)

The curing agent of the present invention, solubility in water of curing component, or to improve the dispersibility, you-containing surfactant (C).
Surfactant as (C) has amphiphilic, may be used any known compound as a surfactant, Ru using a surfactant containing at least one carbodiimide group.
By containing the surfactant (C), it is possible to further improve the solubility or dispersibility of the curing component in a solvent or water, but as described above, at least one carbodiimide group is contained in the surfactant. When it is contained, it is bonded to the cured product (crosslinked resin matrix) at the time of curing (crosslinking reaction), so that the phenomenon that the surfactant adheres to the cured product surface and whitens can be suitably suppressed. Have

In the curing agent of the present invention, such carbodiimide groups and possess surface active agent (C) content is based on the total weight of the curing agent, Ru 90 weight parts der 5. If the amount is less than 5 parts by weight, the additive effect may not be exhibited, and the solubility of the curing component or the dispersibility in water may not be increased efficiently. If the amount is more than 90 parts by weight, the resulting cured product (crosslinked resin) ) May deteriorate in heat resistance and durability.
From this viewpoint, it is preferably 10 to 80 parts by weight, more preferably 15 to 70 parts by weight based on the above criteria.

  Examples of the surfactant (C) containing at least one carbodiimide group include a carbodiimide compound having at least two carbodiimide groups in the molecule, and a functional group having reactivity with the carbodiimide group in the carbodiimide compound. And a surfactant component possessed by at least one of the above, a compound formed by bonding the carbodiimide group and a group formed by a reaction between the carbodiimide group and a functional group having reactivity, or a carbodiimide group in the molecule Reaction between the compound having at least one isocyanate group and the surfactant component having at least one functional group reactive with the isocyanate group, with the functional group having reactivity with the isocyanate group Combining via a group formed from Such things are illustrated.

  Examples of the functional group having reactivity with the carbodiimide group include a carboxyl group, a primary or secondary amino group, a hydroxyl group, an isocyanate group, and a thiol group. Among them, a carboxyl group, an amino group, and a hydroxyl group are preferable, a carboxyl group and a hydroxyl group are more preferable, due to reactivity with a carbodiimide group, dispersibility of the generated surfactant, and the like. Especially preferred.

Examples of functional groups having reactivity with isocyanate groups include primary or secondary amino groups, hydroxyl groups, thiol groups, carboxyl groups, isocyanate groups, and thiol groups. Of these, a primary or secondary amino group and a hydroxyl group are preferred, and a hydroxyl group, particularly an aliphatic hydroxyl group, is preferred from the viewpoint of raw material cost and reactivity.
Examples of the compound having at least two carbodiimide groups in the molecule include the polyvalent cyclic carbodiimide compounds described above, and conventionally known dicarbodiimides and polycarbodiimides of polycarbodiimides, that is, polydisperse A linear or monodispersed linear polyvalent carbodiimide compound or the like can also be used.

Here, polydispersion means dispersion in polymer chemistry and means a mixture having a wide degree of polymerization, and monodispersion means having a single molecular weight.
Examples of such compounds include monodispersed polyvalent carbodiimide compounds described in JP-A-63-264128. Polydispersed polyvalent carbodiimide compounds produced by decarbonylation condensation of diisocyanate compounds are costly. Is preferable.
Examples of the polydispersed polyvalent carbodiimide compound include U.S. Pat. No. 2,941,966, JP-A-2005-15734, and Chem. Rev. vol. 81, 589 (1981) or the like.

In the decarboxylation carbodiimidization of diisocyanate, for example, catalysts described in JP-A No. 11-80522 and the like, especially phospholene oxides such as 3-methyl-1-phenyl-2-phospholene- 1-oxide, 3-methyl-1-ethyl-2-phospholene-1-oxide, 1,3-dimethyl-2-phospholene-1-oxide, 1-phenyl-2-phospholene-1-oxide, 1-ethyl- It is preferably used as a carbodiimidization catalyst such as 2-phospholene-1-oxide, 1-methyl-2-phospholene-1-oxide, and double bond isomers thereof. More preferably, industrially available 3-methyl-1-phenyl-2-phospholene-1-oxide is mentioned.
These carbodiimidization catalysts may be used alone or in combination of two or more. The ratio of the carbodiimidization catalyst used is 0.01 to 10 parts by weight, preferably 0.05 to 5 parts by weight, based on 100 parts by weight of the total isocyanate compound.

The carbodiimidization is carried out in the presence of the above-mentioned carbodiimidization catalyst, for example, in an inert gas atmosphere at 30 to 200 ° C., preferably 60 to 180 ° C. for 1 to 50 hours, preferably 2 to 40 hours.
For the reaction, it is preferable to use a solvent, and an aprotic solvent used in a conventionally known carbodiimidization reaction is used. Examples of such solvents include alkyltoluene such as benzene, toluene, xylene, trimethylbenzene, tetramethylbenzene, cymene, and diethylbenzene, alkylbenzene, naphthalene, acetone, butanone, perchlene, N-methylpyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, cyclohexane, etc. are mentioned.
Among these, toluene, xylene, parklene, trimethylbenzene, tetramethylbenzene, cymene, diethylbenzene, naphthalene and cyclohexane are preferable, and toluene is more preferable. These may be used alone or in combination of two or more.

The aprotic solvent is preferably used so that the solid content in the solution is 1 to 90 wt%. If the solid content concentration is 90 wt% or less, it is possible to prevent the viscosity from increasing or the storage stability of the solution from decreasing. On the other hand, if the solid content concentration is 1 wt% or more, the polydispersed polyvalent carbodiimide compound can be easily obtained as a slurry.
The diisocyanate compound used in the production of the polydispersed polyvalent carbodiimide compound by decarboxylation carbodiimidization is not particularly limited, and diisocyanates usually used in the production of polyurethane resin, such as aliphatic diisocyanate, alicyclic diisocyanate, aromatic fat Group diisocyanates, aromatic diisocyanates, and mixtures thereof.

  Examples of the aliphatic diisocyanate include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, 1,2-butylene diisocyanate, 2,3-butylene diisocyanate, and 1,3-butylene. Examples include diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate and the like.

  Examples of the alicyclic diisocyanate include 1,3-cyclopentene diisocyanate, 1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate, 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (common name) : Isophorone diisocyanate), 4,4′-methylenebis (cyclohexyl isocyanate), 3-methyl-2,4-cyclohexane diisocyanate, 4-methyl-2,6-cyclohexane diisocyanate, 1,3- or 1,4-bis (isocyanate) Natomethyl) cyclohexane (common name: hydrogenated xylylene diisocyanate) or a mixture thereof, and alicyclic diisocyanates such as norbornane diisocyanate.

Examples of the araliphatic diisocyanate include 1,3- or 1,4-xylylene diisocyanate or a mixture thereof, ω, ω′-diisocyanato-1,4-diethylbenzene, 1,3- or 1,4-bis (1 -Isocyanato-1-methylethyl) benzene (common name: tetramethylxylylene diisocyanate) or aromatic aliphatic diisocyanate such as a mixture thereof.
Examples of the aromatic diisocyanate include m-phenylene diisocyanate, p-phenylene diisocyanate, 4,4′-diphenyl diisocyanate, 1,5-naphthalene diisocyanate, 2,4′- or 4,4′-diphenylmethane diisocyanate, or a mixture thereof. Examples include 2,4- or 2,6-tolylene diisocyanate or a mixture thereof, 4,4′-toluidine diisocyanate, 4,4′-diphenyl ether diisocyanate, and the like.

Examples of the diisocyanate derivative include the above-described polyisocyanate dimers, biurets, allophanates, carbodiimides, uretdiones, and oxadiazinetriones.
These diisocyanates may be used alone or in combination of two or more. Of these diisocyanates, isophorone diisocyanate, 4,4′-methylenebis (cyclohexyl isocyanate), 2,4′- or 4,4′-diphenylmethane diisocyanate or a mixture thereof, 2,4- or 2,6- Examples include tolylene diisocyanate or a mixture thereof, tetramethylxylylene diisocyanate and the like.

  The polydisperse polyvalent carbodiimide compound obtained by such a reaction has an isocyanate group at the terminal, but as a molecular weight modifier or terminal blocking agent, a monoisocyanate compound or a compound having a functional group reactive with the isocyanate group In combination, it is possible to reduce the concentration of the terminal isocyanate group, but by reacting the surfactant having a reactive functional group with the isocyanate group, the carbodiimide group-containing surfactant is efficiently obtained. (C) can be obtained.

  In addition, as monoisocyanate which can be used as a terminal blocker, for example, butane isocyanate, hexane isocyanate, decane isocyanate, hexadecane isocyanate, cyclopentane isocyanate, cyclohexane isocyanate, isophorone monoisocyanate), 4-cyclohexylmethylcyclohexyl isocyanate, 3 -Methylcyclohexane isocyanate, 2,6-dimethylcyclohexane-4-isocyanate, norbornane isocyanate, 2,4-dimethylphenyl isocyanate, 2,6-dimethylphenyl isocyanate, 2-isocyanatoethyl-4-ethylbenzene, 2-isocyanatoethyl -3-ethylbenzene, 1-isocyanatoethyl-4-ethylbenzene, 1-isocyanatoethyl- -Ethylbenzene, 1-isocyanato-4-phenylbenzene, 1-isocyanato-3-phenylbenzene, 1-isocyanatonaphthalene, 2-isocyanatonaphthalene, 1-isocyanato-4- (phenylmethyl) benzene, 1-isocyanato-3 -(Phenylmethyl) benzene and the like.

The polydispersed polyvalent carbodiimide, as its name suggests, has a wide degree of polymerization, so it does not matter if it contains some monocarbodiimide component, but the component containing at least two carbodiimides is 50 wt. % Is preferably exceeded.
The polydispersed polyvalent carbodiimide compound has an average degree of polymerization obtained by dividing the number average molecular weight measured by gel permeation chromatography by the molecular weight of the unit component, from 1.5 to 10, more preferably from 1.7 to 7, A range of 1.8 to 5 is preferable from the viewpoint of dispersibility.

  In the present invention, the surfactant component of the surfactant (C) containing a carbodiimide group is preferably a polyalkylene oxide surfactant, particularly preferably a polyalkylene oxide compound represented by the following general formula. is there.

（式中、Ａｒは炭素数２から４のアルキレン基を、Ｆは、前述したカルボジイミド基あるいはイソシアネート基と反応性の官能基であり、ＷはＦとポリアルキレングリコールの酸素原子とを結合する２価の有機基を表す。Ｙは、前記“Ｆ−Ｗ−”と同一であるか、炭素数２から２０の脂肪族アシル基またはアルキル基あるいは炭素数６から２０の脂環族あるいは芳香族アシル基または炭化水素基を、ｎは２から６０の整数を表す。）

(In the formula, Ar is an alkylene group having 2 to 4 carbon atoms, F is a functional group reactive with the above-described carbodiimide group or isocyanate group, and W is a bond between F and the oxygen atom of polyalkylene glycol 2. Y represents the same as the above-mentioned “FW”, or an aliphatic acyl group or alkyl group having 2 to 20 carbon atoms, or an alicyclic or aromatic acyl group having 6 to 20 carbon atoms. A group or a hydrocarbon group, n represents an integer of 2 to 60.)

In the present invention, as described above, the surfactant (C) containing a carbodiimide group is a polyoxyalkylene compound represented by the above formula containing a functional group reactive with isocyanate during the production of a polyvalent carbodiimide. Although it can manufacture suitably by using together, it manufactures by making the polyalkylene oxide type compound represented by the polyvalent carbodiimide compound or the carbodiimide compound which has an isocyanate group manufactured separately react with the said formula. You can also.
Moreover, a commercially available carbodiimide can also be used suitably as a raw material of surfactant (C) containing this carbodiimide group. Examples of such agents are the product names SV-02, V-02, V-02-L2, V-04, which are sold as a crosslinking agent for aqueous resins under the trade name “Carbodilite” by Nisshinbo Chemical Co., Ltd. Examples thereof include E-01 and E-02.

When producing the surfactant (C) containing a carbodiimide group, the polyalkylene oxide compound represented by the above formula is reacted in an amount of 0.5 to 1.5 mol per equivalent of the carbodiimide group of the polyvalent carbodiimide compound. Or by reacting 0.5 to 1.5 mol of the polyalkylene oxide compound represented by the above formula per equivalent of isocyanate group of the carbodiimide compound having an isocyanate group.
The reaction is carried out at 50 to 200 ° C., more preferably 60 to 150 ° C., further preferably 60 to 120 ° C., for 1 to 20 hours, more preferably 1 to 15 hours, still more preferably 2 to 10 hours.
In the reaction, use of a solvent is preferable, and an aprotic solvent is preferable. For example, the solvent used for the carbodiimidization can be preferably used.

  As a functional group having a reactivity with a carbodiimide group or an isocyanate group represented by the above formula, examples of the compound containing a hydroxyl group include homo- or copolymerized polyalkylenes such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol. Glycols such as methoxypolyethylene glycol, ethoxypolyethylene glycol, ethoxypolypropylene glycol, ethoxypolybutylene glycol, polyoxyethylene nonylphenyl ether, polyoxyalkylene alkylphenyl ethers such as polyoxyethylene octylphenyl ether, etc. One terminal hydroxyl group is an alkyl group having 1 to 20 carbon atoms, an alicyclic group having 6 to 20 carbon atoms, an aromatic group, or the like. Or polyalkylene glycols sealed with an aralkyl group having 7 to 20 carbon atoms (hereinafter, these may be collectively referred to as alkoxy polyalkylene glycols), acetoxy polyethylene glycol, propionyloxy polyethylene glycol, decyl Aliphatic acyl groups having 1 to 20 carbon atoms in the above-mentioned polyalkylene glycols such as carbonyloxypolypropylene glycol, oleyloxypolybutylene glycol, monoacetoxypolyoxyethylene glycol, cyclohexylcarbonyloxypolyethylene glycol, etc. Polyalkylene glycols sealed with 6 to 20 alicyclic acyl groups, aromatic acyl groups, or aralkyl acyl groups having 7 to 20 carbon atoms (hereinafter collectively referred to as these) It may be called sill polyalkylene glycols.) And the like.

  Examples of the compound represented by the above formula having a carboxyl group as a functional group having reactivity with a carbodiimide group or an isocyanate group include, for example, the aforementioned polyalkylene glycols, alkoxy polyalkylene glycols, and acylated polyalkylene glycols. Examples thereof include compounds obtained by reacting with acid anhydrides (hereinafter sometimes referred to as carboxylated polyalkylene glycols).

  Here, examples of the acid anhydride include succinic acid anhydride, fumaric acid anhydride, phthalic acid anhydride, pyromellitic acid anhydride, 4,4′-oxydiphthalic acid anhydride, biphenyl-3,3 ′, 4. , 4′-tetracarboxylic anhydride, benzophenone-3,3 ′, 4,4′-tetracarboxylic anhydride, cyclopentanetetracarboxylic anhydride, benzophenone-2,2 ′, 3,3′-tetracarboxylic Acid anhydride, biphenyl-2,2 ′, 3,3′-tetracarboxylic anhydride, 2,2-bis (3,4-dicarboxyphenyl) propane anhydride, bis (3,4-dicarboxyphenyl) Ether anhydride, bis (3,4-dicarboxyphenyl) sulfone anhydride, bis (3,4-dicarboxyphenyl) methane anhydride, 4,4 ′-(P-phenylenedioxy) diphthalate Acid anhydrides, anhydrous 4,4 '- (m- phenylene-oxy) diphthalic acid anhydride, such as naphthalene-1,4,5,8-tetracarboxylic acid anhydride anhydrides are exemplified. Of these, succinic anhydride, fumaric anhydride, phthalic anhydride and the like are preferably selected from the viewpoints of reactivity, industrial convenience, and the like.

In this invention, it can be used for manufacture of surfactant (C) containing a carbodiimide group, As a compound containing a carbodiimide group and an isocyanate group in a molecule | numerator, for example, polydispersion by decarboxylation carbodiimidization of the above-mentioned diisocyanate compound A polyvalent carbodiimide compound is preferably exemplified.
The degree of polymerization of the polydispersed polyvalent carbodiimide compound is broad and may contain a slight amount of diisocyanate compound as long as it does not contradict the gist of the present invention.
Therefore, the average degree of polymerization of the polydispersed carbodiimide is preferably in the range of 0.7 to 5, more preferably 0.8 to 4, and still more preferably 0.9 to 3, from the viewpoint of dispersion performance.
The raw material and production method of such a polydispersed carbodiimide compound are produced according to the above-described agent and method.

In order to obtain a cured product or a coating film by curing an adhesive or a paint containing a carboxyl group-containing resin (A) as a main agent with a curing agent containing the carbodiimide compound (B) of the present invention as a curing component, In addition, after blending the curing agent of the present invention or blending the main agent with the curing agent of the present invention, after application and spraying, the solvent in the curing agent may be volatilized, specifically when used as an adhesive. After applying and spreading the adhesive of the present invention on the surface to be bonded, the bonded surface is bonded, and a cured product having sufficient physical properties can be obtained by leaving it at room temperature or warming conditions for about 1 to 30 minutes, Even when used as a coating material, a coating film having sufficient physical properties can be obtained by leaving it at room temperature or warming conditions for about 1 to 30 minutes after being applied or dispersed on the surface on which the coating film is to be formed. Door can be.
When after-curing, leave it at room temperature for several hours to several days. When the curing rate is too high, the reaction rate can be adjusted by adding a basic substance such as amine or alkali, specifically, triethylamine or sodium hydroxide to the carboxyl group-containing resin (A). .

In the present invention, the main resin contained in the adhesive and paint is not limited as long as it contains a carboxyl group. The carboxyl group content of the resin is preferably 0.01 to 10.0 mmol / g.
When the carboxyl group content is less than 0.01 mmol / g, satisfactory physical properties cannot be obtained because the crosslinking density is small. When the amount exceeds 10 mmol / g, the reaction between the main agent and the curing agent is not “intermolecular” crosslinking, but the ratio of “intramolecular” crosslinking increases, so that sufficient physical properties cannot be obtained. The carboxyl group content is more preferably 0.03 to 8.0 mmol / g.
The number average molecular weight of the carboxyl group-containing resin (A) is preferably 5,000 to 100,000, more preferably 10,000 to 90,000. When the molecular weight is less than 5,000, good physical properties are difficult to obtain. When it exceeds 100,000, workability is inferior, for example, it takes time to blend the main agent and the curing agent.
The carboxyl group-containing resin (A) is not particularly limited, and examples thereof include conventionally known carboxyl group-containing polyesters, acrylic resins, polyurethane resins, polyolefin resins, terminal carboxylated polyolefins and polydienes.

  Specifically, for example, a carboxyl group-containing polychloroprene rubber copolymer latex described in JP-A-11-315263, a carboxyl group-containing polyethylene resin dispersion described in JP-A-2001-172396, or a commercially available agent For example, polyacrylic acid resin or carboxyl group-containing acrylic resin (manufactured by Nippon Shokubai Co., Ltd.) “Aquaric” AS-58 (manufactured by Nippon Carbide Industries Co., Ltd.) “Nicalite” HA-401, (Toho Synthetic Co., Ltd.) "Aronix" M-5600 and the like are carboxyl group-containing polyester resins (manufactured by Kyoyo Chemical Industry Co., Ltd.) plus coat product numbers Z-561, Z-730, RZ-142, (Takamatsu Yushi ( Manufactured by) Pesresin product numbers A-110, A-210, A-620 (manufactured by Toyobo Co., Ltd.) "Bironal" product numbers MD-1200, MD-1220, MD-1250, MD-1335, MD-1400, MD-1480, MD-1500, etc. are examples of the pendant carboxyl group-containing polyester (manufactured by Toyo Ink Manufacturing Co., Ltd.). “Dyna Leo” VA9023 and the like are carboxyl group-containing polyethylene dispersions (manufactured by Toho Chemical Industry Co., Ltd.), Hitech product numbers S-3121 and S-7024, and the like. “Izelux” S-1060 manufactured by Chemical Industry Co., Ltd., and examples of the carboxyl group-containing styrene / butadiene latex (manufactured by Nippon Zeon Co., Ltd., “NIPOL” LX430, LX433C, LX421, etc.).

  In order to obtain a cured product or a coating film by curing an adhesive or a paint containing a carboxyl group-containing resin (A) as a main agent with a curing agent containing the carbodiimide compound (B) of the present invention as a curing component, In blending the curing agent of the present invention or blending the main agent into the curing agent of the present invention, there is no particular limitation, and conventionally known methods, for example, a method of adding a curing composition to the main agent and kneading, or an aqueous solution of the main agent, Methods such as adding an aqueous solution of a curable composition, an aqueous dispersion, a solvent solution or a dispersion to an aqueous dispersion, an organic solvent solution or a dispersion, and stirring can be used.

In addition, as a method for dispersing the curing component in water, a carbodiimide compound (B) and a surfactant (C) containing a carbodiimide group are put into water, or a surfactant (C) containing a carbodiimide compound (B) and a carbodiimide group (C ) And forcibly stirring and dispersing each of them, and after dissolving them in an organic solvent such as acetone, water is added and the solvent is removed.
Organic solvents that can be used when the curing component is made into a solution using an organic solvent include aromatic solvents such as toluene and xylene, ketone solvents such as acetone, methyl ethyl ketone, and cyclohexanone, ethyl acetate, and butyl acetate. Ester solvents such as dimethyl ether, diethyl ether, 1,4-dioxane, tetrahydrofuran and other ether solvents, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, pyridine and the like can be used alone or in combination. .

In the present invention, the mixing ratio of the carboxyl group-containing resin (A) as the main agent and the curing agent is the carboxyl group content of the carboxyl group-containing resin (A), the type and amount of the curing component contained in the curing agent. Generally, the addition amount of the curing agent is 1 to 100 parts by weight, preferably 5 to 60 parts by weight, based on 100 parts by weight of the carboxyl group-containing resin (A). More preferably, it may be about 7 to 50 parts by weight.
When the addition amount of the curing agent is less than 1 part by weight, the crosslinking resin may not have sufficient durability because the crosslinking density is too small. On the other hand, when the amount exceeds 100 parts by weight, the cured resin is diluted with a curing agent that is not involved in the crosslinking reaction, and mechanical properties and the like may be deteriorated.

In addition, when used as an adhesive, in addition to the above main agent and curing agent, if necessary, coloring pigments, matting agents, fillers, fillers, plasticizers, pigment dispersants, thickeners, Any agent known to be contained in an adhesive such as an antifoaming agent may be added as long as the object of the present invention is achieved.
In addition, when used as a paint, it can be used as a clear paint paint by using the above-mentioned main agent and curing agent, and if necessary, a paint composition such as a coloring pigment or a matting agent, or a metallic material containing aluminum flakes. It can be applied to various paints such as paints, and can be used for plastic molded products in a wide range of applications such as housings for household appliances, large structures, automobiles and the like.
Moreover, you may add paint additives, such as a luster material, a filler, a plasticizer, a pigment dispersant, a thickener, an antifoamer, a leveling agent, etc. as needed.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further more concretely, this invention does not receive any limitation by this. In addition, each value in a present Example was calculated | required according to the following method.

1. Softening temperature measurement:
The softening temperature of the resin cured with a curing agent was determined according to JIS K-6253.

2. Gel fraction measurement:
The resin obtained by curing into a film is further cut finely, weighed in advance, put into a cylindrical filter paper, extracted with Soxhlet extractor using methyl ethyl ketone as the extraction solvent, extracted for 10 hours, dried, weighed Then, the gelation rate was determined.

3. Adhesion evaluation:
Two polyethylene terephthalate (PET) films whose surfaces were corona-treated were prepared as objects to be bonded.
On the other hand, an organic solvent-based resin containing a carboxyl group (solid content 50 wt%) or a water-based resin (solid content 50 wt%) and a curing agent were mixed and adjusted as an adhesive, and the above preparation was made within 5 minutes after the adjustment. It apply | coated so that the application quantity after drying might be set to 3 g / m < ² > on the corona treatment surface (one side) of two PET films.
Subsequently, after heating at 80 degreeC for 10 second, it superposed | stacked so that the adhesive application surfaces of two PET films might contact, and left still at 25 degreeC for 3 days. Thereafter, the PET film was cut into a 15 mm width strip to obtain an evaluation sample.
The obtained evaluation samples were evaluated for peel strength at a tensile speed of 200 m / min and a peel direction of 180 degrees.
Samples in which peeling at the adhesive interface did not occur and the film itself was broken were particularly excellent (A), samples with a peel strength of 18.6 N / 15 mm or more were passed (O), and the peel strength was less than 18.6 N / 15 mm The sample was judged as rejected (x).

4). Paint performance test:
As a coating material, 33 parts by weight of titanium oxide and 33 parts by weight of methyl ethyl ketone are blended with 100 parts by weight of a solvent-based resin (solid content: 50 wt%) containing a carboxyl group, and dispersed in a ball mill to form an organic solvent-based coating material. (Before addition of curing agent) was adjusted.
In addition, 33 parts by weight of titanium oxide, 20 parts by weight of water, and 13 parts by weight of isopropyl alcohol are blended with 100 parts by weight of an aqueous resin solution (solid content 50%) containing carboxyl groups, and dispersed by a ball mill. A water-based paint (before adding a curing agent) was prepared.
3 parts by weight of the curing agent was blended with 100 parts by weight of the coating material (before addition of the curing agent) and mixed well.
This was applied to a plate-like aluminum surface so as to have a film thickness of 50 μm after drying, heated at 80 ° C. for 1 minute, and allowed to stand at 25 ° C. for 3 days to obtain a coating sample.
The obtained coating sample was evaluated by the cross cut tape method described in JIS K-5600.

[Production Example] Preparation of raw materials:
The following compounds B1, B2, C1, C2, and C3 were synthesized and prepared as carbodiimide compounds.

[Production Example 1] Synthesis of carbodiimide compound (B1):
Reaction in which 200 ml of o-nitrophenol (0.11 mol), 1,2-dibromoethane (0.05 mol), potassium carbonate (0.33 mol), and N, N-dimethylformamide (DMF) were installed with a stirrer and a heating device The apparatus was charged in an N 2 atmosphere and reacted at 130 ° C. for 12 hours. Then, DMF was removed under reduced pressure, and the resulting solid was dissolved in 200 ml of dichloromethane, followed by liquid separation three times with 100 ml of water. The organic layer was dehydrated with 5 g of sodium sulfate, and dichloromethane was removed under reduced pressure to obtain an intermediate product A (nitro form).
Next, intermediate product A (0.1 mol), 5% palladium carbon (Pd / C) (1 g), and 200 ml of ethanol / dichloromethane (70/30) were charged into a reactor equipped with a stirrer, and 5 hydrogen substitution was performed. The reaction was performed in a state where hydrogen was constantly supplied at 25 ° C., and the reaction was terminated when there was no decrease in hydrogen. Pd / C was recovered and the mixed solvent was removed to obtain an intermediate product B (amine body).

Next, triphenylphosphine dibromide (0.11 mol) and 150 ml of 1,2-dichloroethane were charged and stirred in a reactor equipped with a stirrer, a heating device, and a dropping funnel in an N ₂ atmosphere. A solution prepared by dissolving intermediate product B (0.05 mol) and triethylamine (0.25 mol) in 50 ml of 1,2-dichloroethane was gradually added dropwise thereto at 25 ° C. After completion of dropping, the reaction is carried out at 70 ° C. for 5 hours. Thereafter, the reaction solution was filtered, and the filtrate was separated 5 times with 100 ml of water. The organic layer was dehydrated with 5 g of sodium sulfate, and 1,2-dichloroethane was removed under reduced pressure to obtain an intermediate product C (triphenylphosphine compound).
Next, in a reactor equipped with a stirrer and a dropping funnel, di-tert-butyl dicarbonate (0.11 mol), N, N-dimethyl-4-aminopyridine (0.055 mol), dichloromethane under N ₂ atmosphere. 150 ml was charged and stirred. Thereto, 100 ml of dichloromethane in which the intermediate product C (0.05 mol) was dissolved was slowly added dropwise at 25 ° C. After dropping, the reaction was allowed to proceed for 12 hours. Then, the carbodiimide compound (B1) shown by the following structural formula was obtained by refine | purifying the solid substance obtained by removing dichloromethane (MW = 252). The structure was confirmed by NMR and IR. The carbodiimide compound (B1) has one ring structure (11 members) including one carbodiimide group represented by “—N═C═N—” in one molecule.

[Production Example 2] Synthesis of carbodiimide compound (B2):
o- nitrophenol (0.11 mol) and pentaerythrityl tetra bromide (0.025 mol), potassium carbonate (0.33mol), N, N- dimethylformamide 200ml in reactor installed with a stirrer and a heating device _{N 2} After charging in an atmosphere and reacting at 130 ° C. for 12 hours, DMF was removed under reduced pressure, and the resulting solid was dissolved in 200 ml of dichloromethane and separated three times with 100 ml of water. The organic layer was dehydrated with 5 g of sodium sulfate, and dichloromethane was removed under reduced pressure to obtain an intermediate product D (nitro form).
Next, intermediate product D (0.1 mol), 5% palladium carbon (Pd / C) (2 g), and 400 ml of ethanol / dichloromethane (70/30) were charged into a reactor equipped with a stirrer, and 5 hydrogen substitution was performed. The reaction was performed in a state where hydrogen was constantly supplied at 25 ° C., and the reaction was terminated when there was no decrease in hydrogen. When Pd / C was recovered and the mixed solvent was removed, an intermediate product E (amine body) was obtained.

Next, triphenylphosphine dibromide (0.11 mol) and 150 ml of 1,2-dichloroethane were charged and stirred in a reactor equipped with a stirring device, a heating device, and a dropping funnel in an N ₂ atmosphere. A solution prepared by dissolving the intermediate product E (0.025 mol) and triethylamine (0.25 mol) in 50 ml of 1,2-dichloroethane was gradually added dropwise thereto at 25 ° C. After completion of dropping, the reaction is carried out at 70 ° C. for 5 hours. Thereafter, the reaction solution was filtered, and the filtrate was separated 5 times with 100 ml of water. The organic layer was dehydrated with 5 g of sodium sulfate, and 1,2-dichloroethane was removed under reduced pressure to obtain an intermediate product F (triphenylphosphine compound).
Next, in a reactor equipped with a stirrer and a dropping funnel, di-tert-butyl dicarbonate (0.11 mol), N, N-dimethyl-4-aminopyridine (0.055 mol), dichloromethane under N ₂ atmosphere. 150 ml was charged and stirred. Thereto, 100 ml of dichloromethane in which the intermediate product F (0.025 mol) was dissolved was slowly added dropwise at 25 ° C. After dropping, the reaction was allowed to proceed for 12 hours. Then, the carbodiimide compound (B2) represented by the following structural formula was obtained by refine | purifying the solid substance obtained by removing dichloromethane (MW = 516). The structure was confirmed by NMR and IR. The carbodiimide compound (B2) has two ring structures (member number 12) containing a carbodiimide group represented by “—N═C═N—” in one molecule, and each carbodiimide group contains It is formed including only one.

[Production Example 3] Synthesis of carbodiimide compound (C1):
250 parts by weight of 4,4′-dicyclohexylmethane diisocyanate and 3 parts by weight of a carbodiimidization catalyst (3-methyl-1-phenyl-2-phospholene-1-oxide) were reacted at 170 ° C. for 10 hours in a nitrogen gas atmosphere. Thereafter, 600 parts by weight of polyethylene glycol monomethyl ether having a number average molecular weight of 1000 is blended, reacted at 120 ° C. for 3 hours to urethanate the terminal isocyanate group, and contain 4,4′-dicyclohexylmethanecarbodiimide-linked carbodiimide group. Polyethylene glycol was obtained (carbodiimide polymerization degree = 5.5).

[Production Example 4] Synthesis of carbodiimide compound (C2):
After reacting 250 parts by weight of 4,4′-dicyclohexylmethane diisocyanate with 3 parts by weight of a carbodiimidization catalyst (3-methyl-1-phenyl-2-phospholene-1-oxide) at 170 ° C. for 10 hours, 600 parts by weight Polyethylene glycol monomethyl ether having a number average molecular weight of 1000 was esterified with 60 parts by weight of succinic anhydride, reacted at 120 ° C. for 3 hours to be carbamate-esterified, and carbodiimide linked with 4,4′-dicyclohexylmethanecarbodiimide. A group-containing polyethylene oxide was obtained (carbodiimide polymerization degree = 4.2).

[Production Example 5] Synthesis of carbodiimide compound (C3):
476 parts by weight of isophorone diisocyanate and 600 parts by weight of polyethylene glycol monomethyl ether having a number average molecular weight of 700 were reacted at 90 ° C. for 3 hours in a nitrogen gas atmosphere. Subsequently, 3 parts by weight of (3-methyl-1-phenyl-2-phospholene-1-oxide) was added and reacted at 170 ° C. for 15 hours in a nitrogen gas atmosphere to obtain a carbodiimide compound (C3) (degree of polymerization of carbodiimide = 4). .5) was obtained.

[Example 1]
A curing agent was prepared by mixing 25 parts by weight of the carbodiimide compound (B1), 25 parts by weight of the carbodiimide compound (B2), and 50 parts by weight of the carbodiimide compound (C1) with a homogenizer, and further adding 100 parts by weight of acetone.
On the other hand, a carboxyl group-containing acrylic resin (“Nicalite” HA-401 manufactured by Nippon Carbide Industries Co., Ltd.) as a main ingredient is diluted with methyl ethyl ketone to a solid content of 50 wt%. 10 parts by weight of the agent was added and mixed well.
This mixed solution was cast on a release paper and cured at 60 ° C. for 30 minutes, and then cured at 120 ° C. for 1 hour to obtain a cured product.
The softened temperature of the cured product was 200 ° C. or higher, and the gelation rate was 99% or higher, indicating good curing efficiency (gelation rate) and heat resistance (softening temperature).
Moreover, when the said mixed liquid was used and adhesiveness was evaluated, about the adhesive force, the film destroyed, it was excellent passing, and the paint performance test by the grid tape method was 10 (point). The results are listed in Table 1.

[Examples 2-3, Comparative Examples 1-4]
An adhesive was obtained in the same manner as in Example 1 except that the composition was as described in Table 1. The results are shown in Table 1.

As can be easily understood from Table 1, the curing agent of the present invention has high curing efficiency for solvent-based resins, excellent heat resistance of the resulting cured product, and also has high performance as an adhesive and paint. Can be easily understood.
In addition, when linear polycarbodiimideimide was used, the gelation fraction reached only 95%.

[Example 4]
In the same manner as in Example 1, except that a curing agent was produced with each component listed in Table 2, and the main component was a water-dispersed urethane resin solution containing a carboxyl group ("Eize" manufactured by Hodogaya Chemical Co., Ltd.). 10 parts by weight of a curing agent having the composition shown in Table 2 was added to 100 parts by weight of a urethane resin solution obtained by adjusting Lux “S-1060 with water to a solid content of 50 wt% and mixed well.
This mixed solution was cast on Teflon (registered trademark) paper, cured at 60 ° C. for 30 minutes, and then cured at 120 ° C. for 1 hour to obtain a cured product.
The softening temperature of the cured product was 200 ° C. or higher, gelation rate, good curing efficiency (gelation rate) of 99% or higher, and heat resistance (softening temperature). The results are shown in Table 2 together with the results.
Moreover, when the said mixed liquid was used and adhesiveness was evaluated, about the adhesive force, the film destroyed, it was excellent passing, and the paint performance test by the grid tape method was 10 (point). The results are listed in Table 2.

[Examples 5-6, Comparative Examples 5-8]
In the same manner as in Example 4, except that a curing agent comprising a carbodiimide component and a surfactant described in Table 2 was produced and evaluated. The results are shown in Table 2 together with the results.

As can be easily understood from Table 2, it is easily understood that the curing agent of the present invention is effective for water-based resins as well as the above-mentioned solvent-based resins.
When linear polycarbodiimide was used, the gelation fraction reached only 93% or 94%.

  The curing agent of the present invention can efficiently cure a carboxyl group-containing resin and can be suitably used as a curing agent for adhesives and paints.

Claims (5)

Represented by the following general formula, look-containing carbodiimide compound ring structure is a 8-50 membered ring with (B) as the curing component, hardening agent containing a surface active agent containing a carbodiimide group (C).

(In the formula, Q is a divalent to tetravalent linking group that is an aliphatic group, an alicyclic group, an aromatic group, or a combination thereof, and may contain a hetero atom or a substituent.) An adhesive comprising a main agent and a curing agent, the main agent is a carboxyl group-containing resin (A), the curing agent, the adhesive is a curing agent of claim 1 Symbol placement. A cured product obtained by curing the adhesive according to claim 2 . A paint containing a main agent and a curing agent, the main agent is a carboxyl group-containing resin (A), the curing agent is a curing agent of claim 1 Symbol placement paint. A coating film obtained by curing the paint according to claim 4 .