JP6746461B2 - Polyisocyanate composition, blocked polyisocyanate composition, hydrophilic polyisocyanate composition, coating composition, and coating film - Google Patents

Description

The present invention relates to a polyisocyanate composition, a blocked polyisocyanate composition, a hydrophilic polyisocyanate composition, a coating composition, and a coating film.

Conventionally, a urethane coating film formed from a polyurethane coating has excellent flexibility, chemical resistance, and stain resistance, and is particularly represented by hexamethylene diisocyanate (hereinafter also referred to as HDI). A coating film using a non-yellowing polyisocyanate obtained from an aliphatic diisocyanate as a curing agent is further excellent in weather resistance and its demand is increasing.
2. Description of the Related Art In recent years, with the increasing protection of the global environment, technological development for reducing the viscosity of polyisocyanates used as curing agents has been actively carried out. This is because the amount of the organic solvent used in the coating composition can be reduced by reducing the viscosity of the polyisocyanate (Patent Documents 1 and 2).
Further, a low-viscosity triisocyanate compound alone (Patent Documents 3 to 5) or a technique for converting a part of these triisocyanate compounds to isocyanurate (Patent Document 6) is disclosed, and when these are used, Satisfactory low viscosity and a certain degree of drying property have been obtained.
Further, the performance required of the polyurethane coating film includes adhesion to the substrate. It is widely known to use a buret structure for polyisocyanate in order to impart adhesiveness (Patent Documents 7 and 8).

JP 05-222007 A Japanese Patent No. 3055197 Japanese Patent Publication No. 63-15264 JP-A-53-135931 JP, 60-44561, A Japanese Patent Laid-Open No. 10-87782 JP-A-49-134629 JP, 2002-20452, A

Polyisocyanates containing a buret structure generally have low heat resistance, for example, in fields that require high-temperature baking such as in pre-coated metal applications, and in fields that become extremely hot in the summer, such as in automotive top clear applications. Has a problem that it is difficult to use because the burette structure is decomposed and the coating film is yellowed.
With the polyisocyanates and triisocyanate compounds disclosed in Patent Documents 1 to 8, it has been difficult to achieve all of low viscosity, adhesion, heat resistance, and heat-resistant yellowing of coating compositions.
The present invention provides a polyisocyanate composition having a low viscosity, excellent heat resistance, and capable of forming a coating film having high adhesion to a substrate and high heat yellowing when used in a coating composition. The purpose is to provide.

As a result of intensive studies, the present inventors have found that a polyisocyanate composition having a specific structure can achieve the above-mentioned object, and have completed the present invention.
That is, the present invention is as follows.

[1] A polyisocyanate composition containing a polyisocyanate compound represented by the following general formula (I) and a triisocyanate represented by the following general formula (II)-1 .

［一般式（Ｉ）中、複数あるＲはすべて下記一般式（ＩＩ）で表される基である。］

[In the formula (I), all in multiple R is a group represented by the following general formula (II). ]

［一般式（ＩＩ）中、複数あるＹ^１は、それぞれ独立に、単結合、あるいは、エステル構造及び／又はエーテル構造を含んでもよい炭素数１〜２０の２価の炭化水素基である。複数あるＹ^１は、それぞれ同一であってもよく異なっていてもよい。Ｒ^１は、水素原子又は炭素数１〜１２の１価の炭化水素基である。波線は結合手を意味する。］

[In the general formula (II), a plurality of Y ^1's each independently represent a single bond or a divalent hydrocarbon group having 1 to 20 carbon atoms and optionally containing an ester structure and/or an ether structure. The plurality of Y ^{1 s} may be the same or different. R ¹ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms. The wavy line means a bond. ]

[In Formula (II)-1, a plurality of Ys are present. ¹⁰ Are each independently a single bond or a divalent hydrocarbon group having 1 to 20 carbon atoms which may include an ester structure and/or an ether structure. Multiple Y ¹⁰ May be the same or different. R ¹⁰ Is a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms. ]

[2] A blocked polyisocyanate composition in which at least a part of the isocyanate groups contained in the polyisocyanate composition according to [1] is protected with a blocking agent.
[3] of the polyisocyanate composition according to [1], obtained by adding at least a part a hydrophilic group of the isocyanate group containing a hydrophilic polyisocyanate composition.
[4] A hydrophilic polyisocyanate composition obtained by adding a hydrophilic group to at least a part of the isocyanate groups contained in the blocked polyisocyanate composition according to [2].
[5] A coating composition containing the polyisocyanate composition according to [1] and a polyol.
[6] A coating composition containing the blocked polyisocyanate composition according to [ 2 ] and a polyol.
[7] A coating composition containing the hydrophilic polyisocyanate composition according to [3] or [4] and a polyol.
[8] [5] to cure the coating composition according to any one of to [7], the coating film.

The polyisocyanate composition of the present invention has a low viscosity and excellent heat resistance, and when used in a coating composition, can form a coating film having high adhesion to a substrate and high heat yellowing. ..

Hereinafter, a mode for carrying out the present invention (hereinafter, simply referred to as “the present embodiment”) will be described in detail. The following embodiments are examples for explaining the present invention, and are not intended to limit the present invention to the following contents. The present invention can be appropriately modified and implemented within the scope of the gist.

In the present specification, the “polyisocyanate” refers to a polymer in which a plurality of monomers having one or more isocyanate groups (—NCO) are bound.
In the present specification, the “polyol” refers to a compound having two or more hydroxy groups (—OH).

<Polyisocyanate composition>
The polyisocyanate composition of the present embodiment contains a polyisocyanate compound having a buret structure represented by the general formula (I).
Hereinafter, the polyisocyanate compound represented by the general formula (I) will be described.

≪Polyisocyanate compound≫
The polyisocyanate compound used in this embodiment is represented by the following general formula (I).

［一般式（Ｉ）中、Ｒは有機基である。複数あるＲのうち少なくとも１つは下記一般式（ＩＩ）で表される基である。］

[In general formula (I), R is an organic group. At least one of the plurality of Rs is a group represented by the following general formula (II). ]

［一般式（ＩＩ）中、複数あるＹ^１は、それぞれ独立に、単結合、あるいは、エステル構造及び／又はエーテル構造を含んでもよい炭素数１〜２０の２価の炭化水素基である。複数あるＹ^１は、それぞれ同一であってもよく異なっていてもよい。Ｒ^１は、水素原子又は炭素数１〜１２の１価の炭化水素基である。波線は結合手を意味する。］

[In the general formula (II), a plurality of Y ^1's each independently represent a single bond or a divalent hydrocarbon group having 1 to 20 carbon atoms and optionally containing an ester structure and/or an ether structure. The plurality of Y ^{1 s} may be the same or different. R ¹ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms. The wavy line means a bond. ]

・General formula (I)
The polyisocyanate compound represented by the general formula (I) has a buret structure. The buret structure is a polyisocyanate composed of three molecules of triisocyanate monomer and is represented by the general formula (I).

[R]
In the general formula (I), R is an organic group. At least one of the plurality of Rs is a group represented by the following general formula (II). Plural Rs may be the same or different.
In the present embodiment, at least one of the three Rs is a group represented by the general formula (II), and two R are preferably groups represented by the general formula (II). It is more preferred that all Rs are groups represented by general formula (II).

Examples of groups other than the group represented by the general formula (II) in R include, for example, tetramethylene diisocyanate (TMDI), pentamethylene diisocyanate (PDI), hexamethylene diisocyanate (HDI), and 2,2,4-trimethyl. Hexane-1,6-diisocyanate, 2-methylpentane-1,5-diisocyanate (MPDI), 1,3-bis(isocyanatomethyl)-cyclohexane(1,3-H6-XDI), 3(4)-isocyanate Natomethyl-1-methyl-cyclohexyl isoanate (IMCI); isophorone diisocyanate (IPDI), bis(isocyanatomethyl)-norbornane (NBDI), 1,3-bis(isocyanatomethyl)-benzene, 1,3- Residues obtained by removing an isocyanate group from bis(2-isocyanatopropyl-2)benzene and 4,4′-dicyclohexylmethane diisocyanate (H12MDI) can be mentioned.

As a method of forming a buret structure, there is a method of using a buretizing agent. The buretizing agent is not particularly limited, but examples thereof include water, a monohydric tertiary alcohol, formic acid, hydrogen sulfide, an organic primary monoamine, and an organic primary diamine. In the reaction, the amount of the isocyanate group is preferably 6 mol or more, more preferably 10 mol or more, and particularly preferably 10 mol or more and 80 mol or less, relative to 1 mol of the buretizing agent. If it is at least the above lower limit, the viscosity will be sufficiently low, and if it is at most the above upper limit, curability will be maintained when it is made into a coating composition.
A solvent can be used in the burette reaction. The solvent can dissolve a triisocyanate monomer or diisocyanate monomer and a buretizing agent such as water to form a uniform phase under the reaction conditions.

Specific examples of this solvent include, for example, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol mono-n-propyl ether acetate, ethylene glycol monoisopropyl ether acetate, ethylene glycol mono-n- Butyl ether acetate, ethylene glycol diacetate, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol di-n-propyl ether, ethylene glycol diisopropyl ether, ethylene glycol di-n-butyl ether, ethylene glycol methyl ethyl ether, ethylene glycol methyl isopropyl ether Ethylene glycol methyl-n-butyl ether, ethylene glycol ethyl-n-propyl ether, ethylene glycol ethyl isopropyl ether, ethylene glycol ethyl-n-butyl ether, ethylene glycol-n-propyl-n-butyl ether, ethylene glycol isopropyl-n-butyl ether , Diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol mono-n-propyl ether acetate, diethylene glycol monoisopropyl ether acetate, diethylene glycol mono-n-butyl ether acetate, diethylene glycol diacetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol di-n -Propyl ether, diethylene glycol diisopropyl ether, diethylene glycol di-n-butyl ether, diethylene glycol methyl ethyl ether, diethylene glycol methyl isopropyl ether, diethylene glycol methyl-n-propyl ether, diethylene glycol methyl-n-butyl ether, diethylene glycol ethyl isopropyl ether, diethylene glycol ethyl-n- Examples thereof include propyl ether, diethylene glycol ethyl-n-butyl ether, diethylene glycol-n-propyl-n-butyl ether and diethylene glycol isopropyl-n-butyl ether.

Preferred ethylene glycol-based solvents include ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol diacetate, diethylene glycol dimethyl ether and the like. Further, phosphoric acid-based trimethyl phosphate, triethyl phosphate, tripropyl phosphate, tributyl phosphate and the like can be mentioned, and trimethyl phosphate and triethyl phosphate are preferable. These may be used alone or in admixture of two or more.

The burette reaction temperature is preferably 70°C or higher and 200°C or lower, more preferably 90°C or higher and 180°C or lower. When it is at most the above upper limit, there is a tendency that coloring and the like can be effectively prevented, which is preferable.

・General formula (II)
[Y ¹ ]
In general formula (II), a plurality of Y ^1's each independently may include a single bond or an ester structure [—C(═O)—O—] and/or an ether structure (—O—). It is a divalent hydrocarbon group having 1 to 20 carbon atoms. Plural Y ^{1 s} may be the same or different.
Examples of the divalent hydrocarbon group having ester structure and / or carbon atoms which may contain an ether structure _{1~20, - (CH 2) n1} -X- (CH 2) n2 - group represented by (n1 and n2 Are each independently an integer of 0 to 10. However, it is preferable that both n1 and n2 are not 0, and n1 and n2 are one or more on the side bonded to the NCO. X is an ester group or an ether group).
When it is desired to increase the reaction rate, X is preferably an ester group.
0-4 are preferable and, as for n1 and n2, 0-2 are more preferable. As a combination of n1 and n2, for example, a combination of n1=0 and n2=2, and a combination of n1=2 and n2=2 are preferable.

[R ¹ ]
R ¹ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms. The hydrocarbon group for R ¹ is not particularly limited, and examples thereof include an alkyl group, an alkenyl group and an alkynyl group. R ¹ is preferably a hydrogen atom.

The molecular weight of the triisocyanate which is the source of the group represented by the general formula (II) in the present embodiment is preferably 139 or more and 1000 or less.
The lower limit of the molecular weight is preferably 150 or more, more preferably 180 or more, and particularly preferably 200 or more. The upper limit of the molecular weight is preferably 800 or less, more preferably 600 or less, and particularly preferably 400 or less. When the molecular weight is at least the above lower limit, crystallinity can be easily suppressed. Further, when the molecular weight is not more than the above upper limit value, it becomes easy to achieve low viscosity.

The triisocyanate, which is the source of the group represented by the general formula (II) in the present embodiment, has a low viscosity, and thus a plurality of hydrocarbon groups in Y ¹ may have an aliphatic group or an aromatic group. preferable. In addition, R ¹ is preferably hydrogen.
Further, the hydrocarbon group in Y ¹ preferably has an aliphatic group or an alicyclic group in order to improve weather resistance when used as a curing agent for the coating composition.
Separately, in order to maintain heat resistance, it is preferable that at least one of a plurality of Y ¹ 's has an ester group.

Examples of the triisocyanate which is a source of the group represented by the general formula (II) in the present embodiment include 4-isocyanate methyl-1,8-octamethylene diisocyanate (hereinafter, referred to as WO96/17881). NTI, molecular weight 251), 1,3,6-hexamethylene triisocyanate (hereinafter, referred to as HTI, molecular weight 209) disclosed in JP-A-57-198760, and JP-B-4-1033. Disclosed bis(2-isocyanatoethyl)2-isocyanatoglutarate (hereinafter, referred to as GTI, molecular weight 311), lysine triisocyanate disclosed in JP-A-53-135931 (hereinafter referred to as LTI) The molecular weight is 267).
Among these, NTI, GTI or LTI is preferable, NTI or LTI is more preferable, and LTI is particularly preferable, from the viewpoint of further improving the reactivity of the isocyanate group.

Further, in order to maintain the hydrolysis resistance, at least one of a plurality of Y ¹ preferably has a hydrocarbon group containing an ether structure.

The triisocyanate which is the basis of the group represented by the general formula (II) in the present embodiment can be obtained by isocyanate-forming an amino acid derivative or an amine such as an etheramine or an alkyltriamine. As the amino acid derivative, for example, 2,5-diaminovaleric acid, 2,6-diaminohexanoic acid, aspartic acid, glutamic acid and the like can be used. Since these amino acids are diamine monocarboxylic acid or monoamine dicarboxylic acid, the number of amino groups can be controlled by esterifying the carboxyl group with an alkanolamine such as ethanolamine, or by esterifying the carboxyl group with, for example, methanol. can do. The resulting amine having an ester group can be converted to a triisocyanate or diisocyanate containing an ester structure by phosgenation or the like.
Examples of the ether amine include polyoxyalkylene triamine, which is a trade name “D403” of Mitsui Fine Chemicals, Inc., and the like. This is triamine, and can be converted to triisocyanate containing an ether structure by phosgenation of amine.
Examples of the alkyltriamine include triisocyanatononane (4-aminomethyl-1,8-octanediamine) and the like. This is triamine, and can be converted to triisocyanate containing only hydrocarbons by phosgenation of amines.

The content of the polyisocyanate compound in the polyisocyanate composition of the present embodiment is preferably 1% by mass or more and 100% by mass or less, more preferably 10% by mass or more and 90% by mass or less, and 20% by mass. It is more preferable to be 80% by mass or less. When it is at least the above lower limit, the weather resistance tends to be excellent, and when it is at most the above upper limit, the viscosity is low and workability tends to be excellent.

Further, the polyisocyanate composition of the present embodiment has a compound having a uretdione structure, a compound having an allophanate structure, and an iminodioxadiazinedione structure in addition to the polyisocyanate compound represented by the general formula (I). A compound, a compound having a urethane structure, and a compound having an isocyanurate structure may be included.
The uretdione structure, the allophanate structure, the iminodioxadiazinedione structure, the urethane structure, and the isocyanurate structure are represented by the following formulas (III), (IV), (V), (VI), and (VII), respectively.

The polyisocyanate composition of the present embodiment may further contain the triisocyanate represented by the general formula (II)-1.

［一般式（ＩＩ）−１中、複数あるＹ^１０は、それぞれ独立に、単結合、あるいは、エステル構造及び／又はエーテル構造を含んでもよい炭素数１〜２０の２価の炭化水素基である。複数あるＹ^１０は、それぞれ同一であってもよく異なっていてもよい。Ｒ^１０は、水素原子又は炭素数１〜１２の１価の炭化水素基である。］

[In the general formula (II)-1, a plurality of Y ^10's each independently represent a single bond or a divalent hydrocarbon group having 1 to 20 carbon atoms and optionally containing an ester structure and/or an ether structure. .. The plurality of Y ^{10 s} may be the same or different. R ¹⁰ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms. ]

The description regarding R ¹⁰ and Y ¹⁰ in the general formula (II)-1 is the same as the description regarding R ¹ and Y ¹ in the above general formula (II).

When the known polyisocyanate compositions are made from volatile diisocyanates such as 1,6-hexamethylene diisocyanate, 1,5-pentane diisocyanate, toluene diisocyanate or isophorone diisocyanate, the unreacted starting diisocyanate is finally produced, for example by distillation. Of the polyisocyanate composition to less than 2% by weight, preferably less than 1% by weight. However, when the polyisocyanate composition of the present embodiment is produced, since the number of NCO groups of the triisocyanate used in the present embodiment is 3, the crosslinking ability with the polyol of the polyisocyanate composition of the present embodiment is not reduced, It does not necessarily have to be removed.
When the unreacted triisocyanate is removed, it can be separated from the polyisocyanate composition by a thin film distillation method or a solvent extraction method.

The viscosity at 25° C. of the polyisocyanate composition of the present embodiment is not particularly limited, but is preferably 5 Pa·s or more and 200 mPa·s or less, more preferably 5 Pa·s or more and 100 mPa·s or less. It is particularly preferably 50 mPa·s or less. When it is at least the above lower limit, curability tends to be excellent, and when it is at most the above upper limit, workability tends to be excellent. The viscosity can be measured by using an E-type viscometer (manufactured by Tokimec).

<Block polyisocyanate composition>
The polyisocyanate composition of this embodiment can be made into a blocked polyisocyanate composition by protecting an isocyanate group with a blocking agent. Examples of the blocking agent include alcohol-based, alkylphenol-based, phenol-based, active methylene, mercaptan-based, acid amide-based, acid imide-based, imidazole-based, urea-based, oxime-based, amine-based, imide-based, and pyrazole-based compounds. Can be mentioned. More specific examples of the blocking agent are shown below.
(1) Alcohol type; alcohols such as methanol, ethanol, 2-propanol, n-butanol, sec-butanol, 2-ethyl-1-hexanol, 2-methoxyethanol, 2-etokashiethanol, 2-butoxyethanol,
(2) Alkylphenol type; mono- and dialkylphenols having an alkyl group having 4 or more carbon atoms as a substituent, such as n-propylphenol, iso-propylphenol, n-butylphenol, sec-butylphenol, t-butylphenol. , N-hexylphenol, 2-ethylhexylphenol, n-octylphenol, n-nonylphenol and other monoalkylphenols, di-n-propylphenol, diisopropylphenol, isopropylcresol, di-n-butylphenol, di-t-butylphenol, di- Dialkylphenols such as -sec-butylphenol, di-n-octylphenol, di-2-ethylhexylphenol and di-n-nonylphenol,
(3) Phenol-based; phenol, cresol, ethylphenol, styrenated phenol, hydroxybenzoic acid ester, etc.

(4) Active methylene type; dimethyl malonate, diethyl malonate, methyl acetoacetate, ethyl acetoacetate, acetylacetone, etc.
(5) Mercaptan type; butyl mercaptan, dodecyl mercaptan, etc.
(6) Acid amide type; acetanilide, acetic amide, ε-caprolactam, δ-valerolactam, γ-butyrolactam, etc.,
(7) Acid imide type; succinimide, maleic imide, etc.
(8) Imidazole type; imidazole, 2-methylimidazole, etc.
(9) Urea type; urea, thiourea, ethylene urea, etc.
(10) Oxime-based; formaldoxime, acetaldoxime, acetoxime, methylethylketoxime, cyclohexanoneoxime, etc.
(11) Amine-based; diphenylamine, aniline, carbazole, di-n-propylamine, diisopropylamine, isopropylethylamine, etc.
(12) Imine type; ethyleneimine, polyethyleneimine, etc.
(13) Bisulfite; sodium bisulfite, etc.
(14) Pyrazole-based; pyrazole, 3-methylpyrazole, 3,5-dimethylpyrazole, etc.,
(15) Triazole type; 3,5-dimethyl-1,2,4-triazole and the like.

The blocking reaction between the polyisocyanate composition and the blocking agent can be carried out with or without the presence of a solvent. When using a solvent, it is necessary to use a solvent that is inert to the isocyanate groups. In the blocking reaction, organic metal salts such as tin, zinc and lead, tertiary amine compounds and alkali metal alcoholates such as sodium may be used as catalysts. The reaction can generally be carried out at -20 to 150°C, preferably 30°C to 100°C. If it is at least the above lower limit, the reaction rate tends to be fast, and if it is at most the above upper limit, side reactions tend not to occur.

Among the above-mentioned blocking agents, oxime compounds, acid amide compounds, amine compounds, active methylene compounds, pyrazoles are easily available and from the viewpoint of viscosity, reaction temperature, and reaction time of the produced blocked polyisocyanate composition. It is preferable to contain at least one selected from the group consisting of compounds, methylethylketoxime, ε-caprolactam, diethyl malonate, ethyl acetoacetate, diisopropylamine, and 3,5-dimethylpyrazole are more preferable, and methylethylketoxime and diisopropylamine are preferable. , 3,5-dimethylpyrazole are more preferable, and 3,5-dimethylpyrazole is particularly preferable from the viewpoint of achieving both low-temperature curability and compatibility with polyol. The heat dissociable blocking agent may be used alone or in combination of two or more kinds.

<Hydrophilic polyisocyanate composition>
The polyisocyanate composition of this embodiment is a hydrophilic polyisocyanate composition in which a hydrophilic group is added by reacting a compound containing an active hydrogen group and a hydrophilic group (hydrophilic group-containing compound) with an isocyanate group. You can
The hydrophilic group-containing compound capable of reacting with the isocyanate group is not particularly limited, and examples thereof include compounds containing a nonionic, cationic or anionic hydrophilic group.
The compound that introduces the nonionic hydrophilic group is not particularly limited, and examples thereof include compounds in which ethylene oxide is added to the hydroxyl group of alcohol such as methanol, ethanol, butanol, ethylene glycol, and diethylene glycol. These have active hydrogens that react with isocyanate groups. Of these, monoalcohols, which can improve the water dispersibility of the hydrophilic polyisocyanate composition in a small amount, are preferable. The addition number of ethylene oxide is preferably 4 to 30, and more preferably 4 to 20. When the number of additions of ethylene oxide is 4 or more, it tends to be easy to ensure water solubilization. In addition, when the number of added ethylene oxide is 30 or less, the precipitation of the hydrophilic polyisocyanate composition tends to be less likely to occur during low temperature storage.

The introduction of the cationic hydrophilic group, a method of using a compound having both a cationic group and a functional group having a hydrogen that reacts with an isocyanate group, or previously adding a functional group such as a glycidyl group to the isocyanate group. Then, there is a method of reacting this functional group with a specific compound such as sulfide or phosphine. Among them, the method of utilizing a compound having both a cationic group and hydrogen that reacts with an isocyanate group is easy.

The functional group having hydrogen that reacts with the isocyanate group is not particularly limited, and examples thereof include a hydroxyl group and a thiol group. The compound having both the cationic hydrophilic group and a functional group having hydrogen that reacts with an isocyanate group is not particularly limited, and examples thereof include dimethylethanolamine, diethylethanolamine, diethanolamine, methyldiethanolamine, and N,N-dimethyl. Aminohexanol, N,N-dimethylaminoethoxyethanol, N,N-dimethylaminoethoxyethoxyethanol, N,N,N′-trimethylaminoethylethanolamine, N-methyl-N-(dimethylaminopropyl)aminoethanol, etc. Can be mentioned. Further, the tertiary amino group (cationic hydrophilic group) introduced into the aqueous block polyisocyanate can be quaternized with dimethyl sulfate, diethyl sulfate or the like.
Among these, a tertiary amino group is preferable as the cationic hydrophilic group. When the hydrophilic polyisocyanate composition has a tertiary amino group, a compound such as an anionic compound used for neutralization, which will be described later, easily volatilizes by heating, and as a result, water resistance tends to be further improved.
The cationic hydrophilic group can be introduced in the presence of a solvent. In this case, the solvent preferably does not contain a functional group capable of reacting with an isocyanate group. These solvents are not particularly limited, and examples thereof include ethyl acetate, propylene glycol monomethyl ether acetate, dipropylene glycol dimethyl ether and the like.

The cationic hydrophilic group introduced into the hydrophilic polyisocyanate composition is preferably neutralized with a compound having an anion group. The anion group is not particularly limited, but examples thereof include a carboxyl group, a sulfonic acid group, a phosphoric acid group, a halogen group, and a sulfuric acid group. The compound having a carboxyl group is not particularly limited, and examples thereof include formic acid, acetic acid, propionic acid, butyric acid, lactic acid and the like. Further, the compound having a sulfone group is not particularly limited, and examples thereof include ethanesulfonic acid. Furthermore, the compound having a phosphoric acid group is not particularly limited, and examples thereof include phosphoric acid, acidic phosphoric acid ester and the like. Furthermore, the compound having a halogen group is not particularly limited, but examples thereof include hydrochloric acid and the like. Furthermore, the compound having a sulfate group is not particularly limited, and examples thereof include sulfuric acid and the like. Among these, compounds having one carboxyl group are preferable, and acetic acid, propionic acid and butyric acid are more preferable.

The anionic hydrophilic group is not particularly limited, and examples thereof include a carboxylic acid group, a sulfonic acid group, a phosphoric acid group, a halogen group, and a sulfuric acid group. The blocked polyisocyanate having an anionic hydrophilic group is obtained, for example, by reacting active hydrogen of a compound having both an active group that reacts with an isocyanate group and an anionic group with an isocyanate group of a precursor polyisocyanate composition. be able to.

The compound having both active hydrogen and a carboxylic acid group is not particularly limited, but examples thereof include monohydroxy such as 1-hydroxyacetic acid, 3-hydroxypropanoic acid, 12-hydroxy-9-octadecanoic acid, hydroxypivalic acid and lactic acid. Carboxylic acid; polyhydroxycarboxylic acids such as dimethylolacetic acid, 2,2-dimethylolbutyric acid, 2,2-dimethylolpentanoic acid, dihydroxysuccinic acid and dimethylolpropionic acid. Among these, hydroxypivalic acid and dimethylolpropionic acid are preferable.

The compound having both active hydrogen and a sulfonic acid group is not particularly limited, and examples thereof include isethionic acid.

The anionic hydrophilic group introduced into the hydrophilic polyisocyanate composition is not particularly limited, but can be neutralized with an amine compound that is a basic substance, for example. The amine compound is not particularly limited, but examples thereof include ammonia and water-soluble amino compounds. The water-soluble amino compound is not particularly limited, but for example, monoethanolamine, ethylamine, dimethylamine, diethylamine, triethylamine, propylamine, dipropylamine, isopropylamine, diisopropylamine, triethanolamine, butylamine, dibutylamine, 2 Primary or secondary amines such as ethylhexylamine, ethylenediamine, propylenediamine, methylethanolamine, dimethylethanolamine, diethylethanolamine, morpholine; and tertiary amines such as triethylamine and dimethylethanolamine.

The polyisocyanate composition of this embodiment can be used as a mixture with different isocyanate compounds.
The isocyanate compound of the present embodiment is a di-isocyanate or poly-isocyanate having an aliphatic, alicyclic or aromatic isocyanate group. Examples of the diisocyanate include tetramethylene diisocyanate (TMDI), pentamethylene diisocyanate (PDI), hexamethylene diisocyanate (HDI), 2,2,4-trimethylhexane-1,6-diisocyanate, and 2-methylpentane-1,5. -Diisocyanate (MPDI), 1,3-bis(isocyanatomethyl)-cyclohexane (1,3-H6-XDI), 3(4)-isocyanatomethyl-1-methyl-cyclohexyl isocyanate (IMCI); isophorone Diisocyanate (IPDI), bis(isocyanatomethyl)-norbornane (NBDI), 1,3-bis(isocyanatomethyl)-benzene, 1,3-bis(2-isocyanatopropyl-2)benzene and 4,4'. -Dicyclohexylmethane diisocyanate (H12MDI), lysine diisocyanate (LDI) and the like. Among them, HDI and IPDI are preferable from the viewpoint of weather resistance and industrial availability. These diisocyanates may be used alone or in combination of two or more.
The polyisocyanate, using a catalyst, by heating, is a polymer of the diisocyanate, isocyanurate structure, uretdione structure, allophanate structure, iminodioxadiazinedione structure, urethane structure in the molecule, Includes burette structure and so on. Among them, those having an isocyanurate structure are preferable from the viewpoint of weather resistance.

The polyisocyanate composition of this embodiment can also be suitably used as a curing agent for coating compositions. That is, a coating composition containing the polyisocyanate composition of the present embodiment can be obtained. As the resin component of the coating composition, it is preferable to contain a compound having two or more active hydrogens having reactivity with an isocyanate group in the molecule. Examples of the compound having two or more active hydrogens in the molecule include polyol, polyamine, polythiol and the like. Among these, polyol is preferable. Specific examples of the polyol include polyester polyol, polyether polyol, acrylic polyol, polyolefin polyol, and fluorine polyol.

<Other compounds>
The polyisocyanate composition of the present embodiment contains one or more compounds selected from the group consisting of an unsaturated bond-containing compound, an inert compound, a metal atom, a basic amino compound and carbon dioxide, based on the polyisocyanate compound. The content of 0.0 mass ppm or more and 1.0×10 ⁴ mass ppm or less is preferable from the viewpoint of preventing coloration during long-term storage and improving long-term storage stability. The lower limit of the content range is more preferably 3.0 mass ppm or more, further preferably 5.0 mass ppm or more, further preferably 10 mass ppm or more, and the content of The upper limit of the range is more preferably 5.0×10 ³ mass ppm or less, further preferably 3.0×10 ³ mass ppm or less, and 1.0×10 ³ mass ppm or less. Even more preferable.

The unsaturated bond-containing compound is preferably a compound whose unsaturated bond is a carbon-carbon unsaturated bond, a carbon-nitrogen unsaturated bond or a carbon-oxygen unsaturated bond. From the viewpoint of the stability of the compound, the unsaturated bond is preferably a compound which is a double bond, and a carbon-carbon double bond (C=C) or a carbon-oxygen double bond (C=O) is present. More preferable. Moreover, it is preferable that the carbon atoms constituting the compound are bonded to three or more atoms.
Generally, the carbon-carbon double bond may be a carbon-carbon double bond constituting an aromatic ring, but the unsaturated bond contained in the unsaturated bond-containing compound is an aromatic ring. Does not include a carbon-carbon double bond constituting
Examples of the compound having a carbon-oxygen double bond include a carbonic acid derivative. Examples of the carbonic acid derivative include a urea compound, a carbonic acid ester, an N-unsubstituted carbamic acid ester, and an N-substituted carbamic acid ester.

The inactive compound of this embodiment is classified into the following compound A to compound G.
Hydrocarbon compounds are compounds A and B, ether compounds and sulfide compounds are the following compounds C to E, halogenated hydrocarbon compounds are the following compounds F, silicon-containing hydrocarbon compounds, silicon-containing ether compounds and silicon-containing sulfide compounds. Are classified into the following compound G respectively. In addition, the compounds A to G listed here do not include an unsaturated bond other than the aromatic ring, and do not include the above-mentioned compound having an unsaturated bond.
Compound A: an aliphatic hydrocarbon compound having a linear, branched or cyclic structure.
Compound B: An aromatic hydrocarbon compound which may be substituted with an aliphatic hydrocarbon group.
Compound C: a compound having an ether bond or a sulfide bond and an aliphatic hydrocarbon group, wherein the same or different aliphatic hydrocarbon compound is bonded via an ether bond or a sulfide bond.
Compound D: a compound having an ether bond or a sulfide bond and an aromatic hydrocarbon group, in which aromatic hydrocarbon compounds of the same kind or different kinds are bonded via an ether bond or a sulfide bond.
Compound E: A compound having an ether bond or a sulfide bond, an aliphatic hydrocarbon group, and an aromatic hydrocarbon group.
Compound F: A halide in which at least one hydrogen atom constituting an aliphatic hydrocarbon compound or at least one hydrogen atom constituting an aromatic hydrocarbon compound is substituted with a halogen atom.
Compound G: A compound in which some or all of the carbon atoms of Compounds A to E above are substituted with silicon atoms.

The metal atom of this embodiment may be present as a metal ion or as a metal atom simple substance. One kind of metal atom may be used, or plural kinds of metal atoms may be combined. As the metal atom, a metal atom capable of having a valence of 2 to 4 is preferable, and among them, one or more kinds of metal selected from iron, cobalt, nickel, zinc, tin, copper and titanium are more preferable.

The basic amino compound of the present embodiment is a derivative of ammonia, which is a compound (primary) in which one hydrogen is substituted with an alkyl group or an aryl group, a compound (secondary) in which two hydrogens are substituted, and There are compounds (tertiary) that are both substituted. The basic amino compounds that can be preferably used in the present invention are secondary and tertiary amino compounds, and aliphatic amines, aromatic amines, heterocyclic amines, and basic amino acids can be preferably used.

Carbon dioxide may be a polyisocyanate dissolved content under normal pressure, or may be placed in a pressure vessel and dissolved under pressure. Since the use of carbon dioxide containing water may cause hydrolysis of the polyisocyanate compound, it is preferable to control the amount of water contained in carbon dioxide as necessary.

The halogen atom content of the polyisocyanate composition of the present embodiment is preferably 1.0×10 ² mass ppm or less from the viewpoint of preventing coloration. The halogen atom is not particularly limited, but chlorine and/or bromine is preferable, and it is at least one ion and/or compound selected from chlorine ion, bromine ion, hydrolyzable chlorine, and hydrolyzable bromine. More preferable. Examples of hydrolyzed chlorine include a carbamoyl chloride compound in which hydrogen chloride is added to an isocyanate group, and examples of hydrolyzable bromine include a carbamoyl bromide compound in which hydrogen bromide is added to an isocyanate group.

<Paint composition>
The coating composition using the polyisocyanate composition, the blocked polyisocyanate composition or the hydrophilic polyisocyanate composition of the present embodiment can be used on both a solvent base and an aqueous base.
In the case of a solvent-based coating composition, a resin containing a compound having two or more active hydrogens in the molecule, or a solvent dilution thereof, may be added with other resin, catalyst, pigment, leveling agent, Antioxidants, ultraviolet absorbers, light stabilizers, plasticizers, those containing additives such as surfactants, the polyisocyanate composition of the present embodiment is added as a curing agent, if necessary, further solvent Is added to adjust the viscosity, and then a solvent-based coating composition can be obtained by stirring by hand or by using a stirring device such as a Magellar.

In the case of a water-based coating composition, an aqueous dispersion of a resin containing a compound having two or more active hydrogens in the molecule, or a water-soluble product, and if necessary, other resin, catalyst, pigment, leveling Agent, antioxidant, ultraviolet absorber, light stabilizer, plasticizer, to those to which additives such as surfactants are added, the polyisocyanate composition of the present embodiment is added as a curing agent, if necessary, A water-based coating composition can be obtained by further adding water or a solvent and then forcibly stirring with a stirring device.

Examples of the polyester polyol include succinic acid, adipic acid, dimer acid, maleic anhydride, phthalic anhydride, isophthalic acid, terephthalic acid, dibasic acids such as carboxylic acids such as 1,4-cyclohexanedicarboxylic acid, etc. Mixture with ethylene glycol, propylene glycol, diethylene glycol, 1,4-butanediol, neopentyl glycol, 1,6-hexanediol, trimethylpentanediol, cyclohexanediol, trimethylolpropane, glycerin, pentaerythritol, 2-methylolpropanediol , A polyhydric alcohol such as ethoxylated trimethylolpropane, or a mixture thereof, can be obtained by a condensation reaction. For example, the condensation reaction can be carried out by combining the above components and heating at about 160-220°C. Furthermore, for example, polycaprolactones obtained by ring-opening polymerization of lactones such as ε-caprolactone using a polyhydric alcohol can also be used as the polyester polyol. These polyester polyols can be modified with aromatic diisocyanates, aliphatic diisocyanates, alicyclic diisocyanates, and polyisocyanates obtained from them. In this case, aliphatic diisocyanates, alicyclic diisocyanates, and polyisocyanates obtained from them are particularly preferable from the viewpoint of weather resistance and yellowing resistance. When used as an aqueous base paint, some carboxylic acid such as dibasic acid is left behind and neutralized with a base such as amine or ammonia to obtain a water-soluble or water-dispersible product. It can be a resin.

Examples of the polyether polyol include, for example, a hydroxide (lithium, sodium, potassium, etc.), a strongly basic catalyst (alcoholate, alkylamine, etc.), a complex metal cyanide compound complex (metal Porphyrin, zinc hexacyanocobaltate complex, etc.), etc. are used to randomly or block-add a alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, cyclohexene oxide, styrene oxide, etc.) alone or as a mixture to a polyvalent hydroxy compound. Polyether polyols obtained; Polyether polyols obtained by reacting polyamine compounds (ethylenediamines and the like) with alkylene oxide; and so-called polymer polyols obtained by polymerizing acrylamide and the like using these polyether polyols as a medium And the like.

Examples of the polyvalent hydroxy compound include (i) diglycerin, ditrimethylolpropane, pentaerythritol, dipentaerythritol and the like, and (ii) erythritol, D-threitol, L-arabinitol, ribitol, xylitol, sorbitol, and the like. Sugar alcohol compounds such as mannitol, galactitol and rhamnitol, (iii) monosaccharides such as arabinose, ribose, xylose, glucose, mannose, galactose, fructose, sorbose, rhamnose, fucose and ribodeose, (iv) eg trehalose. , Disaccharides such as sucrose, maltose, cellobiose, gentiobiose, lactose and melibiose, (v) trisaccharides such as raffinose, gentianose and melezitose, and (vi) tetrasaccharides such as stachyose.

The acrylic polyol can be obtained, for example, by copolymerizing a polymerizable monomer having one or more active hydrogens in one molecule with another monomer copolymerizable with the polymerizable monomer.

Acrylic polyols are, for example, acrylic acid esters having active hydrogen (2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxybutyl acrylate, etc.), or methacrylic acid esters having active hydrogen. (2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, 3-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, etc.), glycerin, trimethylolpropane, etc. (Meth)acrylic acid esters having polyvalent active hydrogen such as (meth)acrylic acid monoester of triol; polyether polyols (polyethylene glycol, polypropylene glycol, polybutylene glycol, etc.) and the above active hydrogen (meth) ) Monoethers with acrylic acid esters; adducts of glycidyl (meth)acrylate with monobasic acids such as acetic acid, propionic acid, p-tert-butylbenzoic acid; (meth)acrylic acid esters having the above active hydrogen If necessary, at least one selected from the group consisting of adducts obtained by ring-opening polymerization of lactones (ε-caprolactam, γ-valerolactone, etc.) with active hydrogen of the group (meth) Acrylic esters (methyl acrylate, ethyl acrylate, isopropyl acrylate, -n-butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, -n-butyl methacrylate, Isobutyl methacrylate, n-hexyl methacrylate, cyclohexyl methacrylate, lauryl methacrylate, glycidyl methacrylate, etc., unsaturated carboxylic acids (acrylic acid, methacrylic acid, maleic acid, itaconic acid, etc.), unsaturated amides (acrylamide , N-methylolacrylamide, diacetoneacrylamide, etc.), or vinyl monomers having a hydrolyzable silyl group (vinyltrimethoxysilane, vinylmethyldimethoxysilane, γ-(meth)acrylopropyltrimethoxysilane, etc.), other It can be obtained by copolymerizing one or more selected from the group consisting of polymerizable monomers (styrene, vinyltoluene, vinyl acetate, acrylonitrile, dibutyl fumarate, etc.) by a conventional method.

For example, the above-mentioned monomer component is solution polymerized in the presence of a radical polymerization initiator such as a known peroxide or azo compound, and an acrylic polyol is obtained by diluting it with an organic solvent or the like as necessary. You can When an aqueous base acrylic polyol is obtained, it can be produced by a known method such as solution polymerization of an olefinically unsaturated compound and conversion into an aqueous layer, or emulsion polymerization. In that case, water solubility or water dispersibility can be imparted by neutralizing acidic moieties such as carboxylic acid-containing monomers such as acrylic acid and methacrylic acid and sulfonic acid-containing monomers with amines and ammonia.

The fluoropolyol is a polyol containing fluorine in the molecule, and examples thereof include fluoroolefins, cyclovinyl ethers, hydroxyalkyl vinyl ethers disclosed in JP-A-57-34107 and JP-A-61-21531. Examples thereof include copolymers such as vinyl monocarboxylic acid ester.

The hydroxyl value of the polyol is not particularly limited, but is preferably 10 mgKOH/g or more and 200 mgKOH/g or less. Among them, the lower limit value is more preferably 20 mgKOH/g, and particularly preferably 30 mgKOH/g. The acid value of the polyol is preferably 0 mgKOH/g or more and 30 mgKOH/g or less. The hydroxyl value and the acid value can be measured according to JIS K1557.

Among the above, as the polyol, acrylic polyol is preferable from the viewpoint of weather resistance, chemical resistance, and hardness, and polyester polyol is preferable from the viewpoint of mechanical strength and oil resistance.

The equivalent ratio (NCO/OH ratio) of the isocyanate group of the polyisocyanate composition of the present embodiment to the hydroxyl group of the compound having two or more active hydrogens in the molecule is preferably 0.2 or more and 5.0 or less, 0.4 or more and 3.0 or less are more preferable, and 0.5 or more and 2.0 or less are especially preferable. When the equivalent ratio is at least the above lower limit, it is possible to obtain a tougher coating film. When the equivalent ratio is not more than the above upper limit value, the smoothness of the coating film can be further improved.
If necessary, a melamine-based curing agent such as a complete alkyl type, a methylol type alkyl, or an imino group type alkyl can be added to the coating composition.

Any of the compound having two or more active hydrogens in the molecule, the polyisocyanate composition of the present embodiment, and the coating composition can be used as a mixture with an organic solvent. The organic solvent preferably has no functional group that reacts with a hydroxyl group or an isocyanate group. Further, it is preferable that the polyisocyanate composition is compatible with the polyisocyanate composition. Examples of such organic solvents include ester compounds, ether compounds, ketone compounds, aromatic compounds, ethylene glycol dialkyl ether compounds, polyethylene glycol dicarboxylate compounds, and hydrocarbon solvents that are generally used as coating solvents. , Aromatic solvents and the like.

The compound having two or more active hydrogens in the molecule, the polyisocyanate composition and the coating composition of the present embodiment are all catalysts depending on the purpose or use thereof, as long as the effects of the present embodiment are not impaired. It is also possible to mix and use various additives used in the technical field, such as pigments, leveling agents, antioxidants, ultraviolet absorbers, light stabilizers, plasticizers and surfactants.

Examples of the catalyst for accelerating curing are metal salts such as dibutyltin dilaurate, tin 2-ethylhexanoate, zinc 2-ethylhexanoate, cobalt salt; triethylamine, pyridine, methylpyridine, benzyldimethylamine, N,N-. Examples include tertiary amines such as dimethylcyclohexylamine, N-methylpiperidine, pentamethyldiethylenetriamine, N,N′-endoethylenepiperazine, N,N′-dimethylpiperazine, and the like.

The coating composition using the polyisocyanate composition of the present embodiment as a curing agent can be used as a coating material for roll coating, curtain flow coating, spray coating, bell coating, electrostatic coating and the like. For example, it is useful as a primer or a top intermediate coating material for materials such as metals (steel plates, surface-treated steel plates, etc.), plastics, wood, films, inorganic materials and the like. It is also useful as a paint for imparting cosmetic properties, weather resistance, acid resistance, rust resistance, chipping resistance, etc. to pre-coated metal containing rust-proof steel plates, automobile coatings, and the like. It is also useful as a urethane raw material for adhesives, pressure-sensitive adhesives, elastomers, foams, surface treatment agents and the like.

Hereinafter, the present embodiment will be described more specifically with reference to specific examples and comparative examples, but the present embodiment is not limited to the following examples and comparative examples unless the gist thereof is exceeded. Absent. Physical properties of the polyisocyanate compositions in Examples and Comparative Examples were measured as follows. In addition, unless otherwise specified, "parts" and "%" mean "parts by mass" and "% by mass".

<Viscosity>
The viscosity was measured at 25° C. using an E-type viscometer (manufactured by Tokimec). A standard rotor (1°34′×R24) was used for the measurement. The rotation speed is as follows.
100 rpm (when less than 128 mPa·s)
50 rpm (in the case of 128 mPa·s to 256 mPa·s)
20 rpm (in the case of 256 mPa·s to 640 mPa·s)
10 rpm (for 640 mPa·s to 1280 mPa·s)
5 rpm (for 1280 mPa·s to 2560 mPa·s)

<NCO content>
The NCO content (mass %) was determined by back titration with 1N hydrochloric acid after neutralizing the isocyanate groups in the measurement sample with an excess of 2N amine.

<Low viscosity degree of polyisocyanate composition>
From the viscosity measurement results of the polyisocyanate composition, ◯ when the temperature is 50 mPa·s/25° C. or lower, Δ when 50 mPa·s/25° C. or higher and 200 mPa·s/25° C. when 200 mPa·s/25° C. or lower Was designated as x.

<Heat resistance evaluation of polyisocyanate composition>
The polyisocyanate composition was allowed to stand in an environment of a temperature of 90° C. for 10 hours, and when the increase rate of viscosity was less than 2 times, it was evaluated as ◯, and when it was 2 times or more, it was evaluated as x.

<Method for evaluating curability of coating composition using polyisocyanate composition>
Acrylic polyol (Nuplex Resin's trade name "SETALUX 1753", resin content concentration 70%, hydroxyl value 138.6 mgKOH/g) and polyisocyanate composition were each mixed at an isocyanate group/hydroxyl group equivalent ratio of 1.0. Then, the solid content was adjusted to 50% by mass with butyl acetate. The adjusted coating composition was applied onto a glass plate so that the dry film thickness was 40 μm, and then cured at 23° C./50% RH to form a coating film. After a specific time elapsed, a cotton ball (a cylindrical type having a diameter of 2.5 cm and a height of 2.0 cm) was placed on the coating film, and a 100 g weight was placed on the cotton ball for 60 seconds. Then, the weight and the cotton were removed, and the traces of the cotton remaining on the coating film were observed. ◎ when the time when the mark was completely invisible was less than 7 hours, ◯ when it was more than 7 hours to less than 8 hours, △ when more than 8 hours to less than 10 hours, and more than 10 hours. If there was, it was marked as x.

<Evaluation of coating film adhesion of coating composition using polyisocyanate composition>
A coating composition was prepared by the above method, and an aluminum plate was applied to a coated plate so that the dry film thickness was 40 μm, and the mixture was allowed to stand at room temperature for 30 minutes and then in an oven at 140° C. for 30 minutes to form a coating film. Was formed. The produced coating film was subjected to a 100-square cross-cut adhesion test. When the peeling was 0 squares, it was evaluated as ◯, when 1 to 50 cells was evaluated as Δ, when 51 to 100 cells was evaluated as x.

<Evaluation of heat-resistant yellowing of coating film of coating composition using polyisocyanate composition>
A coating composition was prepared by the above method, coated on a glass plate so as to have a dry film thickness of 40 μm, allowed to stand at room temperature for 30 minutes, and then allowed to stand in an oven at 140° C. for 30 minutes to form a coating film. .. The obtained coating film was left in an environment of 150° C. for 24 hours, and the yellowing degree was measured by the following method. The transmittance of the coating composition at 380 to 780 nm was measured with a spectrophotometer (V-650 manufactured by JASCO Corporation), and X, Y, and Z were obtained from JIS Z8701 from the measurement result of the spectrophotometer. YI was calculated from the obtained X, Y, and Z according to JIS K7373 and JIS Z8720. If the difference in YI before and after standing was less than 10, it was rated as O, and if it was 10 or more, it was rated as X.

<Lower viscosity of blocked polyisocyanate composition>
From the viscosity measurement results of the blocked polyisocyanate composition, the case of less than 1000 mPa·s/25° C. was marked with ◯, and the case of 1000 mPa·s/25° C. or above was marked with x.

<Heat resistance evaluation of blocked polyisocyanate composition>
The blocked polyisocyanate composition was allowed to stand in an environment of a temperature of 90° C. for 20 hours, and when the increase rate of viscosity was less than 2 times, it was evaluated as ◯, and when it was 2 times or more, it was evaluated as x.

<Drying property evaluation method for coating composition using blocked polyisocyanate composition>
Acrylic polyol (Nuplex Resin's trade name "SETALUX 1753", resin content concentration 70%, hydroxyl value 138.6 mgKOH/g) and each of the blocked polyisocyanate compositions were compounded at an isocyanate group/hydroxyl group equivalent ratio of 1.0. Then, the solid content was adjusted to 50 mass% with butyl acetate. The prepared coating composition was applied on a glass plate so that the dry film thickness was 40 μm, and then cured at 100° C. for 30 minutes to form a coating film. A cotton ball (columnar shape having a diameter of 2.5 cm and a height of 2.0 cm) was placed on the coating film, and a 100 g weight was placed on the cotton ball for 60 seconds. Then, the weight and the cotton were removed, and the traces of the cotton remaining on the coating film were observed. The case where the mark was completely invisible was rated as O, and the case where the mark was visible was rated as X.

<Evaluation of coating film adhesion of coating composition using blocked polyisocyanate composition>
A coating composition was prepared by the above method, and an aluminum plate was applied to a coated plate so that the dry film thickness was 40 μm, and the mixture was allowed to stand at room temperature for 30 minutes and then in an oven at 140° C. for 30 minutes to form a coating film. Was formed. The produced coating film was subjected to a 100-square cross-cut adhesion test. When the peeling was 0 squares, it was evaluated as ◯, when 1 to 50 cells was evaluated as Δ, when 51 to 100 cells was evaluated as x.

<Evaluation of heat-resistant yellowing of coating film of coating composition using blocked polyisocyanate composition>
A coating composition was prepared by the above method, coated on a glass plate so as to have a dry film thickness of 40 μm, and allowed to stand at room temperature for 30 minutes, and then allowed to stand in an oven at 140° C. for 30 minutes to form a coating film. .. The obtained coating film was left in an environment of 150° C. for 24 hours, and the yellowing degree was measured by the following method. The transmittance of the coating composition at 380 to 780 nm was measured with a spectrophotometer (V-650 manufactured by JASCO Corporation), and X, Y, and Z were obtained from JIS Z8701 from the measurement result of the spectrophotometer. YI was calculated from the obtained X, Y, and Z according to JIS K7373 and JIS Z8720. If the difference in YI before and after standing was less than 10, it was rated as O, and if it was 10 or more, it was rated as X.

<Low viscosity degree of hydrophilic polyisocyanate composition>
From the viscosity measurement results of the hydrophilic polyisocyanate composition, the case of less than 1000 mPa·s/25° C. was marked with ◯, and the case of 1000 mPa·s/25° C. or above was marked with x.

<Heat resistance evaluation of hydrophilic polyisocyanate composition>
The hydrophilic polyisocyanate composition was allowed to stand in an environment of a temperature of 90° C. for 20 hours, and when the increase rate of viscosity was less than 2 times, it was evaluated as ◯, and when it was 2 times or more, it was evaluated as x.

<Drying evaluation method for hydrophilic polyisocyanate composition>
Acrylic dispersion (trade name "SETAQUA6510" of Nuplex Resin Co., resin concentration 42%, hydroxyl group concentration 4.2% (resin standard)) and polyisocyanate composition, each having an isocyanate group/hydroxyl group equivalent ratio of 1.0. Was blended with and adjusted with water to a solid content of 40% by mass. The prepared coating composition was applied on a glass plate so that the dry film thickness was 40 μm, and then cured at 23° C./50% RH to form a coating film. After a specific time elapsed, a cotton ball (a cylindrical type having a diameter of 2.5 cm and a height of 2.0 cm) was placed on the coating film, and a 100 g weight was placed on the cotton ball for 60 seconds. Then, the weight and the cotton were removed, and the traces of the cotton remaining on the coating film were observed. The case where the time when the mark was completely invisible was within 10 hours was marked with ◯, and the case where it was over 10 hours was marked with x.

<Evaluation of coating film adhesion of coating composition using hydrophilic polyisocyanate composition>
A coating composition was prepared by the above method, an aluminum plate was applied to a coated plate so as to have a dry film thickness of 40 μm, and the mixture was allowed to stand at room temperature for 30 minutes and then left in an oven at 120° C. for 30 minutes to form a coating film. Was formed. The produced coating film was subjected to a 100-square cross-cut adhesion test. When the peeling was 0 squares, it was evaluated as ◯, when 1 to 50 cells was evaluated as Δ, when 51 to 100 cells was evaluated as x.

<Evaluation of heat resistant yellowing of coating film of coating composition using hydrophilic polyisocyanate composition>
A coating composition was prepared by the above method, coated on a glass plate to a dry film thickness of 40 μm, and allowed to stand at room temperature for 30 minutes, and then allowed to stand in an oven at 120° C. for 30 minutes to form a coating film. .. The obtained coating film was left in an environment of 150° C. for 24 hours, and the yellowing degree was measured by the following method. The transmittance of the coating composition at 380 to 780 nm was measured with a spectrophotometer (V-650 manufactured by JASCO Corporation), and X, Y, and Z were obtained from JIS Z8701 from the measurement result of the spectrophotometer. YI was calculated from the obtained X, Y, and Z according to JIS K7373 and JIS Z8720. If the difference in YI before and after standing was less than 10, it was rated as O, and if it was 10 or more, it was rated as X.

<Method for evaluating storage stability>
300 g of the polyisocyanate composition was placed in a 500 mL container, and the atmosphere was replaced with nitrogen, and the composition was stored at 23° C. for 300 days.
When the change in the number average molecular weight (after storage/before storage) was less than 1.5, the storage stability was judged to be good.

(Synthesis Example 1) Synthesis of LTI In a four-necked flask equipped with a stirrer, a thermometer, and a gas inlet tube, 122.2 g of ethanolamine, 100 ml of o-dichlorobenzene, and 420 ml of toluene were put, and ice-cooled hydrogen chloride gas was added. Introduced and converted the ethanolamine to the hydrochloride salt. Next, 182.5 g of lysine hydrochloride was added, the reaction solution was heated to 80° C., ethanolamine hydrochloride was dissolved, and hydrogen chloride gas was introduced to give lysine dihydrochloride. Further, hydrogen chloride gas was passed at 20 to 30 ml/min, the reaction solution was heated to 116° C., and this temperature was maintained until water did not distill. The resulting reaction mixture was recrystallized in a mixed solution of methanol and ethanol to obtain 165 g of lysine β-aminoethyl ester trihydrochloride. 100 g of this lysine β-aminoethyl ester trihydrochloride was suspended as fine powder in 1200 ml of o-dichlorobenzene, and the temperature of the reaction solution was raised while stirring. When 120° C. was reached, phosgene was added at 0.4 mol/hour. Blowing at a speed was started, the temperature was maintained for 10 hours, and then the temperature was raised to 150°C. The suspension was mostly dissolved. After cooling, filtration was carried out, the dissolved phosgene and the solvent were distilled off under reduced pressure, and then vacuum distillation was carried out to obtain 80.4 g of colorless and transparent LTI having a boiling point of 155 to 157° C./0.022 mmHg. The NCO content of this product was 47.1% by weight.

(Synthesis Example 2) Synthesis of NTI In a four-necked flask equipped with a stirrer, a thermometer, and a gas inlet tube, 1060 g of 4-aminomethyl-1,8-octamethylenediamine (hereinafter referred to as triamine) was added to 1500 g of methanol. It was dissolved, and 1800 ml of 35% concentrated hydrochloric acid was gradually added dropwise thereto while cooling. Methanol and water were removed under reduced pressure, the mixture was concentrated, and dried at 60° C./5 mmHg for 24 hours to give white solid triamine hydrochloride. The obtained triamine hydrochloride (650 g) was suspended in 5000 g of o-dichlorobenzene as a fine powder, the temperature of the reaction solution was raised with stirring, and when 100°C was reached, phosgene was blown into the reaction mixture at a rate of 200 g/Hr. Then, the temperature was further raised and maintained at 180° C., and phosgene was continuously blown for 12 hours. After distilling off the dissolved phosgene and the solvent under reduced pressure, by vacuum distillation, a colorless transparent 4-isocyanate methyl-1,8-octane methylene diisocyanate (hereinafter referred to as “NTI”) having a boiling point of 161 to 163° C./1.2 mmHg. That said,) 420 g was obtained. The NCO content of this product was 50.0% by weight.

(Example 1) Synthesis of P-1 A 4-necked flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen blowing tube was placed in a nitrogen atmosphere, and 100 g of NTI as a monomer, 20 g of trimethylphosphoric acid, 20 g of methyl cellosolve acetate, 1.2 g of water (NCO group/water molar ratio=18) was charged, and the temperature was kept at 90° C. for 1 hour. Then, the temperature was raised to 160° C. and the temperature was maintained for 2 hours to obtain a polyisocyanate composition P-1. The viscosity of the obtained polyisocyanate composition P-1 was 43 mPa·s/25° C., and the NCO content was 43.4 mass %.
Furthermore, the polyisocyanate composition P-1 has a low viscosity degree of ◯, a heat resistance of ◯, a drying property of P-1 used in a coating composition of ◯, a coating adhesion of ◯, and a coating heat resistant yellow. The denaturation was ◯. The evaluation results are shown in Table 1.

(Examples 2 to 6, Comparative Example 1)
The procedure of Example 1 was repeated, except that the monomers and yields shown in Table 1 were as described. Further, the viscosity of the obtained polyisocyanate composition, the NCO content, the degree of viscosity reduction, the heat resistance, the drying property when the obtained polyisocyanate composition is used for a coating composition, the adhesion of a coating film, the coating film The evaluation results of heat yellowing are shown in Table 1.

(Comparative example 2)
The reaction liquid obtained in Comparative Example 1 was fed to a thin film evaporator to remove unreacted HDI to obtain polyisocyanate composition S-2. The viscosity of the obtained polyisocyanate composition S-2 was 11000 mPa·s/25° C., and the NCO content was 21.2 mass %.
Further, the polyisocyanate composition S-2 has a low viscosity degree, x, heat resistance, x, when S-2 is used in a coating composition, dryness is x, coating adhesion is ◯, coating heat resistant yellow. The denaturation was x. The evaluation results are shown in Table 1.

(Comparative example 3)
Using the NTI synthesized in Synthesis Example 2, it was designated as polyisocyanate composition P-9. The polyisocyanate composition S-3 has a low viscosity degree of ○, a heat resistance of ×, a drying property of S-3 used in a coating composition of ○, a coating adhesion of ×, and a heat resistant yellowing of the coating. It was ○. The evaluation results are shown in Table 1.

In Table 1, the materials indicated by abbreviations mean the following materials.
・TBA: tertiary butyl alcohol ・TMP: trimethyl phosphate ・MCA: methyl cellosolve acetate

(Example 7)
A 4-necked flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen blowing tube was placed in a nitrogen atmosphere and charged with 20 g of the polyisocyanate composition P-1 obtained in Example 1 and 17.5 g of butyl acetate. Then, the temperature was heated to 70° C., 20.9 g of 3,5-dimethylpyrazole was then added with stirring, the temperature was maintained at 70° C., and the mixture was stirred for 1 hour. As a result, the NCO content became 0.0%. Isocyanate composition P-7 was obtained. The viscosity of the obtained blocked polyisocyanate composition was 230 mPa·s/25°C.
Further, the obtained block polyisocyanate composition has a low viscosity degree of ◯, a heat resistance of ◯, and when P-7 is used in a coating composition, a drying property of ◯, an adhesive property of ◯, and a heat-resistant yellowing property of ◯. Met. The evaluation results are shown in Table 2.

(Examples 8-12, Comparative Examples 4-6)
The same procedure as in Example 7 was performed except that the amounts of 3,5-dimethylpyrazole and butyl acetate added in Table 2 were as described. In addition, the viscosity of the obtained block polyisocyanate composition, the degree of viscosity reduction, heat resistance, the drying property when the obtained polyisocyanate composition is used in a coating composition, the adhesion, the evaluation results of heat yellowing The results are shown in Table 2.

(Example 13)
A nitrogen atmosphere was established in a 4-necked flask equipped with a stirrer, a thermometer, a reflux condenser tube, and a nitrogen blowing tube, and 20 g of the polyisocyanate composition P-1 obtained in Example 1 and polyethylene oxide which is a hydrophilic compound. (Nippon Emulsifier Co., Ltd., trade name “MPG-130” number average molecular weight=420) was charged in an amount of 8.7 g, and the mixture was heated to 100° C. and stirred for 4 hours to obtain a hydrophilic polyisocyanate P-13. The viscosity of the obtained hydrophilic polyisocyanate composition was 90 mPa·s/25°C.
Further, the obtained hydrophilic polyisocyanate composition has a low viscosity degree of ◯, a heat resistance of ◯, when P-13 is used in a coating composition, a drying property of ◯, a coating film adhesion of ◯, a coating film The heat-resistant yellowing was ◯. The results of these evaluations are shown in Table 3.

(Examples 14-18, Comparative Examples 7-9)
Example 13 was carried out in the same manner as in Example 13 except that the amount of MPG-130 added in Table 3 was changed as described. Further, the viscosity of the obtained hydrophilic polyisocyanate composition, the degree of viscosity reduction, the degree of viscosity reduction, heat resistance, the drying property when the obtained hydrophilic polyisocyanate composition is used in a coating composition, a coating film. Table 3 shows the evaluation results of adhesion and heat-resistant yellowing of the coating film.

(Example 19)
To 3,300 g of the polyisocyanate composition P-1 obtained in Example 1, 0.03 g of 2,2,4-trimethylpentane was added.
The polyisocyanate composition has a low viscosity degree of ◯, a heat resistance of ◯, a drying property of P-1 used in a coating composition of ◯, a coating film adhesion of ◯, a coating film heat yellowing of ◯, The storage stability evaluation result was good.

(Example 20)
0.03 g of hexadecane was added to 300 g of the polyisocyanate composition P-1 obtained in Example 1.
The polyisocyanate composition has a low viscosity degree of ◯, a heat resistance of ◯, a drying property of P-1 used in a coating composition of ◯, a coating film adhesion of ◯, a coating film heat yellowing of ◯, The storage stability evaluation result was good.

(Synthesis example 3)
A four-necked flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen blowing tube was put in a nitrogen atmosphere, charged with 20 g of NTI, heated to 60° C., added with 7.7 g of methanol, and stirred for 4 hours. Holding, N-substituted carbamic acid ester C-1 was obtained.

(Example 21)
To 300 g of the polyisocyanate composition P-1 obtained in Example 1, 0.03 g of N-substituted carbamic acid ester C-1 was added.
The polyisocyanate composition has a low viscosity degree of ◯, a heat resistance of ◯, a drying property of P-1 used in a coating composition of ◯, a coating film adhesion of ◯, a coating film heat yellowing of ◯, The storage stability evaluation result was good.

From the above, the polyisocyanate composition of each example to which the present invention is applied, the block polyisocyanate composition, or the hydrophilic polyisocyanate composition has a low viscosity, and is excellent in heat resistance, and the polyisocyanate of each example. It was confirmed that the coating composition using the composition had excellent drying property, coating film adhesion and coating film heat-resistant yellowing.

The coating composition using the polyisocyanate composition of the present invention as a curing agent can be used as a coating material for roll coating, curtain flow coating, spray coating, bell coating, electrostatic coating and the like. Further, it can be used as a primer or a top coat paint for metals such as steel plates and surface-treated steel plates, and materials such as plastics, woods, films and inorganic materials. Further, it is also useful as a paint that imparts heat resistance, cosmetics (surface smoothness, sharpness), etc. to pre-coated metal containing rust-proof steel plate, automobile coating, etc. Further, it is also useful as a urethane raw material for adhesives, pressure-sensitive adhesives, elastomers, foams, surface treatment agents and the like.

Claims (8)

A polyisocyanate compound represented by the following general formula (I) ,
A triisocyanate represented by the following general formula (II)-1,
A polyisocyanate composition comprising:

[In the formula (I), all in multiple R is a group represented by the following general formula (II). ]

[In the general formula (II), a plurality of Y ^1's each independently represent a single bond or a divalent hydrocarbon group having 1 to 20 carbon atoms and optionally containing an ester structure and/or an ether structure. The plurality of Y ^{1 s} may be the same or different. R ¹ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms. The wavy line means a bond. ]

[In the general formula (II)-1, a plurality of Y ^10's each independently represent a single bond or a divalent hydrocarbon group having 1 to 20 carbon atoms and optionally containing an ester structure and/or an ether structure. .. The plurality of Y ^{10 s} may be the same or different. R ¹⁰ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms. ] A blocked polyisocyanate composition, wherein at least a part of the isocyanate groups contained in the polyisocyanate composition according to claim 1 is protected with a blocking agent. Polyisocyanate composition according to claim 1, obtained by adding at least a part a hydrophilic group of the isocyanate group containing a hydrophilic polyisocyanate composition. A hydrophilic polyisocyanate composition obtained by adding a hydrophilic group to at least a part of the isocyanate groups contained in the blocked polyisocyanate composition according to claim 2. A coating composition comprising the polyisocyanate composition according to claim 1 and a polyol. A coating composition comprising the blocked polyisocyanate composition according to claim 2 and a polyol. A coating composition comprising the hydrophilic polyisocyanate composition according to claim 3 or 4 and a polyol. And curing the coating composition according to any one of claims 5-7, the coating film.