JPH09302069A - Blocked isocyanate compound - Google Patents

Abstract

(57) Abstract: [PROBLEMS] To provide a blocked aliphatic isocyanate compound having a blocking agent dissociating ability at a lower temperature than conventionally used blocked aliphatic isocyanate compounds. SOLUTION: General formula (I) (In the formula, R ¹ , R ² and R ³ are the same or different,
The present invention provides a blocked isocyanate compound represented by (representing an active hydrogen compound residue).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a low-temperature dissociative blocked isocyanate compound useful as a curing agent for one-pack paints, powder paints and the like for coating metals, plastics, wood, concrete and the like.

[0002]

2. Description of the Related Art Urethane (or urea) resin coatings that utilize the cross-linking reaction between polyisocyanate compounds and polyols (or polyamines) are highly reactive and can be used under room temperature curing conditions. The product after cross-linking is superior to other paints in that it shows high impact resistance, high corrosion resistance, high stain resistance, etc. due to its high cross-linking density, and it is conventionally used for automobiles, home appliances, It is widely used as a paint for large buildings. However, conversely, when the urethane (or urea) resin coating is used, the reactivity between the polyisocyanate compound and the polyol (or polyamine) is high, and therefore the isocyanate curing agent and the polyol (or polyamine) system are stored during storage. It must be used as a so-called two-component paint in which the resin main component is separated and these are mixed immediately before use. For this reason, the workability becomes complicated and it becomes difficult to use it in automated line painting or the like.
Therefore, in order to solve these problems, a shift to a one-pack type paint has been studied. In addition, VOC regulations (Volati
le Organic Compounds Regu
There is an increasing social demand for the shift to low-solvent type, water-based type or powder type paints, which are compatible with environmental measures such as volatile organic substance regulations).

Blocking of isocyanate groups has been devised as a method for addressing the above problems. Blocking is a method in which a suitable active hydrogen compound (blocking agent) and an isocyanate compound are reacted in advance to protect (block) the isocyanate group (blocking of the isocyanate group) and inactivate the isocyanate compound. The blocked isocyanate compound thus obtained does not react with the polyol (or polyamine) -based main component, which is the main component of the coating composition, at room temperature and exists stably, but the heating dissociates the blocking component to regenerate the isocyanate group. However, a urethane (or urea) reaction with a polyol (or polyamine) -based main agent becomes possible. As a result, it became possible to make the paint into one liquid, and due to the properties of the blocking agent, it became possible to develop it into low solvent type, water type or powder type paint.

As a use example of the blocked isocyanate compound, a blocked isocyanate compound blocked with a suitable blocking agent and a polyol resin are used, and the molar ratio of the blocked isocyanate group to the hydroxyl group in the polyol resin is, for example, 1.0. And a catalyst that promotes dissociation of the blocking agent into the isocyanate group and / or a catalyst that promotes dissociation of the blocking agent, to obtain a one-pack type coating composition stable at room temperature. An isocyanate group regenerated from a blocked isocyanate compound is obtained by applying the coating composition to an object to be coated such as a metal by an appropriate method, and then baking and curing it at a temperature of about 150 to 200 ° C. for about 30 minutes. And the hydroxyl group react with each other to form a urethane bond to form a cured coating film.

A typical blocked isocyanate compound is Progress in Organic C.
orting, 3 , 73-99 (1975), the same 9 , 3
-28 (1981), Journal of Appl.
ied PolymerScience, 23 , 353
-365 (1979) and the like, various blocked isocyanate compounds using phenols, oximes, lactams and the like as blocking agents are described. However,
Each of these blocked isocyanate compounds has a high dissociation temperature of the blocking agent, and requires baking at a high temperature when used. For this reason, not only an increase in energy cost and an accompanying increase in air pollution but also a problem occurs when coating a heat-sensitive object such as plastic parts which increases with the weight reduction of automobiles.

Therefore, some methods have been proposed to reduce the curing temperature. For example, JP-A-57-142959 and JP-A-3-17116 disclose low-temperature dissociative blocked isocyanate compounds (and coating compositions containing the same) depending on the type of blocking agent. . In addition, JP-A-4-292675
No. 5,25,433 and the like disclose low-temperature curable coating compositions (including blocked isocyanate) using a curing-accelerating catalyst. However, the above methods are all related to the expression of the low temperature dissociation ability depending on the performance of the blocking agent or the catalyst.

On the other hand, tolylene diisocyanate (TD
In the case of using a compound obtained by protecting the isocyanate group of an aromatic isocyanate compound represented by I) with an active hydrogen compound, for example, blocked TDI, the same isocyanate group of an aliphatic isocyanate compound such as hexamethylene diisocyanate (HDI) is used. In comparison with the case where a compound protected with an active hydrogen compound, for example, blocked HDI is used, dissociation of the blocking agent may proceed at a lower temperature, but the blocked TDI causes extreme yellowing during baking. It is known to cause this, and it is difficult to use it for automobile paints and home electric paints, where appearance is important. Therefore,
There is a demand for an aliphatic blocked isocyanate compound which is capable of low temperature dissociation.

Further, the special low-temperature dissociation type blocking agents as disclosed in the above publications include phenols, oximes,
Compared with conventionally used general-purpose blocking agents such as lactams, they are disadvantageous in terms of supply in actual industrial use, and provide low-temperature dissociative blocked isocyanate compounds using conventional general-purpose blocking agents. Is very effective in reality.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to provide a blocked aliphatic isocyanate compound having a dissociation ability of a blocking agent at a lower temperature than the conventionally used blocked aliphatic isocyanate compound. .

[0010]

DISCLOSURE OF THE INVENTION The present inventors have found that aliphatic 3
By using lysine aminoethyl ester triisocyanate (LTI) as the functional isocyanate compound, when blocked with the same blocking agent, other isocyanate compounds such as HDI and isophorone diisocyanate (IPDI), or isocyanurate compounds using them It was found that the blocking agent is dissociated and the isocyanate group is regenerated at a lower temperature than when a polyisocyanate compound is used, and the present invention has been completed.

That is, the present invention has the general formula (I)

[0012]

Embedded image

[Wherein R ¹ , R ² and R ³ are the same or different and each represents an active hydrogen compound (blocking agent) residue]. Hereinafter, the compound represented by formula (I) is referred to as compound (I). The same applies to compounds of other formula numbers.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Examples of the active hydrogen compound include alcohols, phenols, thiols, oximes, amides, amines, imines, imides and ureas. (II)

[0015]

Embedded image

Wherein R ⁴ represents substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl or substituted or unsubstituted heteroaryl, and X represents O or S. Alcohols, phenols or thiols represented by the general formula (III)

[0017]

Embedded image

(Wherein R ⁵ and R ⁶ are the same or different and each represents a substituted or unsubstituted alkyl, a substituted or unsubstituted cycloalkyl, a substituted or unsubstituted aryl or a substituted or unsubstituted heteroaryl. ) Represented by the general formula (IV)

[0019]

Embedded image

(Wherein R ⁷ represents hydrogen, alkyl, cycloalkyl or amino, R ⁸ and R ⁹ are the same or different and are hydrogen, substituted or unsubstituted alkyl,
An amide represented by substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl or substituted or unsubstituted heteroaryl, or R ⁸ and R ⁹ together represent lower alkylene, a general formula (V)

[0021]

[Chemical 12]

(In the formula, R ¹⁰ and R ¹¹ are the same or different and each represents a substituted or unsubstituted alkyl, a substituted or unsubstituted cycloalkyl, a substituted or unsubstituted aryl or a substituted or unsubstituted heteroaryl. Suka
R ¹⁰ and R ¹¹ together represent lower alkylene) or an amine or imine represented by: or a substituted or unsubstituted carbazole, the general formula (VI)

[0023]

Embedded image

(Wherein R ¹² and R ¹³ are the same or different and represent a substituted or unsubstituted alkyl or a substituted or unsubstituted cycloalkyl, or R ¹² and R ¹³ are taken together to form a lower alkylene. Where Y represents hydrogen or hydroxy) or an imide represented by the general formula (VII
)

[0025]

Embedded image

(Wherein R ¹⁴ , R ¹⁵ and R ¹⁶ are the same or different and are hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl or substituted or unsubstituted Of the above, and Z represents O or S). Specific examples include alcohols such as methanol, ethanol, 2-ethylhexanol, butyl cellosolve, ethylene glycol and propylene glycol monomethyl ether, phenols such as phenol, cresol, ethylphenol and butylphenol, thiols such as butylmercaptan and mercaptothiazoline. , Oximes such as acetone oxime, methyl isobutyl ketoxime, cyclohexanone oxime, acetanilides, acetic acid amides, δ-valerolactam, γ-butyrolactam, α-amino-ε-caprolactam and other amides, dibutylamine, diphenylamine, aniline,
Amines such as carbazole, imines such as ethyleneimine and polyethyleneimine, imides such as succinimide, N-hydroxysuccinimide and maleic imide,
Urea such as urea, ethylene urea, and thiourea are more preferable.

In the definitions of the groups of the general formula (II) to the general formula (VII), the alkyl moiety of alkyl and alkoxy has a straight or branched chain having 1 to 12 carbon atoms, for example, methyl, ethyl, Examples include propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isoamyl, neopentyl, 2-pentyl, hexyl, octyl, nonyl, decyl, undecyl, dodecyl, etc., and cycloalkyl has 3 carbon atoms. ~ 1
2, for example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, cycloundecyl, cyclododecyl, etc., and the lower alkylene has 1 to 6 carbon atoms, such as methylene. ,ethylene,
Examples thereof include propylene, butylene, pentylene, hexylene and the like. Aryl includes phenyl, naphthyl, anthranyl and the like, and heteroaryl includes pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, quinolyl, isoquinolyl, phthalazinyl, naphthyridinyl, quinoxalinyl, cinnolinyl, thienyl, furyl, pyrrolyl, imidazolyl, pyrazolyl, triazolyl. , Tetrazolyl, thiazolyl, oxazolyl, indolyl, indazolyl, benzimidazolyl, benzotriazolyl, purinyl and the like. Halogen means each atom of fluorine, chlorine, bromine and iodine.

Substituents on the substituted alkyl and the substituted cycloalkyl are the same or different and have 1 to 3 substituents, for example, alkoxy, halogen, substituted or unsubstituted aryl or substituted or unsubstituted heteroaryl and the like. . In the definition of the substituent, the alkyl part of the alkoxy has the same meaning as the above alkyl, and halogen, aryl and heteroaryl have the same meanings as the above, and the substituted aryl and the substituted heteroaryl have the same or different substituents. Examples thereof include those having 1 to 3 substitutions, such as alkyl, alkoxy, and halogen. Alkyl, alkoxy, and halogen are as defined above.

Substituents on substituted aryl, substituted heteroaryl and substituted carbazole include, for example, alkyl,
Examples thereof include cycloalkyl, alkoxy, halogen, aryl and the like. In the definition of the substituent, alkyl, cycloalkyl, alkoxy, halogen and aryl are as defined above. Next, the present invention will be described in detail.

Blocked isocyanate compound (I)
Can be produced, for example, according to the following method.
The compound (I) is added with a blocking agent to LTI in a nitrogen atmosphere, and optionally in the presence of a catalyst in an inert solvent or without a solvent, at 0 to 100 ° C, preferably room temperature to 80 ° C, more preferably 60. It can be obtained by reacting at -80 ° C for 3 to 50 hours. When adding blocking agent,
If the heat generation is large, avoid dropping the temperature rapidly while dropping.
The end point of the reaction is the time when the absorption of the isocyanate group disappears by IR.

The starting material LTI is, for example, JP-A-61-53.
249 or a method similar thereto. The blocking agents may be used alone or in combination of two or more. The addition amount of the blocking agent is not particularly limited, but is usually such that the molar ratio of the isocyanate group and active hydrogen is 0.8 to 2.0, preferably 1.0 to 1.1. Examples of the solvent include aromatic hydrocarbons such as benzene and toluene, esters such as ethyl acetate, ketones such as methyl ethyl ketone, and tetrahydrofuran (TH
Examples thereof include ethers such as F). Examples of the catalyst include tin-based catalysts such as dibutyldichlorotin and dibutyldilauryltin, zinc-based catalysts such as zinc 2-ethylnexanthate, iron-based catalysts such as iron chloride, and amine-based catalysts such as triethylamine.

After completion of the reaction, the compound (I) may be purified by subjecting it to a purification method commonly used in synthetic organic chemistry, for example, filtration, extraction, washing, drying, concentration, recrystallization, various chromatography and the like. it can. The compound (I) obtained by the above method stably exists as a solid, viscous liquid or amorphous body at room temperature.

When the blocked isocyanate compound (I) of the present invention is used as a curing agent in a one-pack type coating composition, if necessary, a catalyst such as dibutyldichlorotin or dibutyldilauryltin, hydroquinone, etc. Additives that are usually used as additives for paints, such as antioxidants such as, UV absorbers such as benzophenone, pigments such as titanium oxide, can be added.

The polyol used in the one-pack type coating composition may be an organic polyol having two or more hydroxyl groups in the molecule, for example, saturated polyester resin, unsaturated polyester resin, saturated or unsaturated polyester resin. Examples of the oil-modified or fatty acid-modified alkyd resin, aminoalkyd resin, polyether resin, epoxy resin, polyurethane resin, acrylic polyol, nitrocellulose, cellulose acetate butyrate resin and the like.

Next, the blocking agent dissociation temperature of the blocked LTI compound of the present invention will be shown in Test Examples.

Test Example Blocking Agent Dissociation Temperature Measurement The blocking agent dissociation temperature was measured for the blocked LTI compounds obtained in Examples 1 to 9 and the compounds obtained in Comparative Examples 1 to 3. The dissociation temperature was evaluated by the presence or absence of absorption of isocyanate groups by IR. The measurement results are shown in Table 1.

[0037]

[Table 1]

As shown in Table 1, blocked LT
The compound I has the ability to dissociate the blocking agent at a lower temperature than the blocked HDI isocyanurate compound.
Hereinafter, embodiments of the present invention will be described in detail with reference to examples.

[0039]

[Examples] Identification analysis was performed using the following measuring devices and methods. ¹ H-NMR: 400 MHz superconducting nuclear magnetic resonance analyzer GSX-400 manufactured by JEOL Ltd., measured with CDCl ₃ solvent or DMSO-d ₆ solvent FT-IR: JEOL Fourier transform infrared Using spectrophotometer JIR-3050, KBr method or NaC
Measurement by l-plate method Elemental analysis: Yanaco Seisakusho's elemental analyzer corder
Measurement with MT-5 type Also, for performance evaluation, PERKIN ELMER LI
MITED Fourier Transform Infrared Spectrophotometer System
m2000 and a dedicated heating cell 0019-200,
It was heated and measured.

Example 1 (Synthesis of methylisobutyl ketoxime block LTI) 30 equipped with a thermometer, a Dimroth condenser tube and a nitrogen introduction tube
LTI in a 0 ml four-neck separa flask, 88.2 g
(0.33 mol) was charged, and methyl isobutyl ketoxime (MIBK) was stirred while cooling in water under a nitrogen atmosphere.
120 g (1.04 mol) of O) was added dropwise over 2 hours. After the dropping, the reaction was carried out at 70 ° C. for 5 hours, and it was confirmed by IR that the absorption of the isocyanate group had disappeared, and the reaction was terminated. By the above reaction, 198 g of a pale yellow viscous liquid product was obtained at room temperature.

(Identification analysis) ¹ H-NMR (CDCl ₃ ) δ (ppm): 0.91
~ 0.98 (m, 18H), 1.34 to 1.50 (m,
2H), 1.56 to 1.84 (m, 4H), 1.88 to
2.02 (m, 12H), 2.10 to 2.39 (m, 6
H), 3.20 to 3.34 (m, 2H), 3.53 to
3.61 (m, 2H), 4.31 (t, 2H, J = 5.
37 Hz), 4.49 (q, 4H, J = 5.62H
z), 6.30 to 6.38 (bs, 1H), 6.56 to
6.63 (bs, 1H), 6.72 to 6.80 (bs,
1H) FT-IR (NaCl plate) ν (cm ⁻¹ ): 3338
(Amide NH stretch), 2871-2958 (aliphatic C
-H stretch), 1726 (ester and amide C = O stretch), no absorption of -N = C = O near 2270 cm- ¹ .

Elemental analysis: Calculated value (%) Analytical value (%) Relative error (%) C 56.68 55.78 −1.59 H 8.55 8.50 −0.58 N 13.72 13.77 -0.36 From the above analysis, it was confirmed that the obtained compound had MI in which all three isocyanate groups of LTI were blocked with MIBKO.
It was identified as BKO block LTI.

Example 2 (Synthesis of Phenol Block LTI) 50 equipped with a thermometer, a Dimroth condenser tube and a nitrogen inlet tube
In a 0 ml four-necked separa flask, LTI, 107 g (0.
40 mol), 119 g of phenol (1.26 mo)
l), dibutyldichlorotin 0.36 g (1.2 mmo
1) and 300 ml of toluene were charged, and under a nitrogen atmosphere,
The reaction was carried out at 70-80 ° C for 7 hours. The reaction was terminated by confirming that the absorption of the isocyanate group disappeared by IR.
After allowing to cool to room temperature, the precipitate was filtered, washed (toluene), and dried to obtain 167 g of a white solid product at room temperature.

(Identification analysis) ¹ H-NMR (CDCl ₃ ) δ (ppm): 1.43
˜1.69 (m, 4H), 1.74˜2.01 (m, 2
H), 3.28 (t, 2H, J = 6.35Hz), 3.
42-3.61 (m, 2H), 4.31 (t, 2H, J
= 5.00 Hz), 4.40 (q, 1H, J = 5.56)
Hz), 5.12 to 5.20 (bs, 1H), 5.60
˜5.68 (bs, 1H), 5.72 (d, 1H, J =
7.32 Hz), 7.07 to 7.40 (m, 15H) FT-IR (KBr) ν (cm ^-1 ): 3318 (amide NH stretch), 2866 to 3066 (aliphatic CH stretch) , 1709, 1740 (ester and amide C = O
(Expansion and contraction), no absorption of -N = C = O near 2270 cm ^-1

Elemental analysis: Calculated value (%) Analytical value (%) Relative error (%) C 63.38 63.70 +0.50 H 5.69 5.78 +1.58 N 7.65 7.64 −0 .13 From the above analysis, the obtained compound was identified as a phenol block LTI in which all three isocyanate groups of LTI were blocked with phenol.

Example 3 (Synthesis of 1,1,1,3,3,3-hexafluoroisopropanol block LTI) 5 equipped with a thermometer and a Dimroth cooling tube with a nitrogen introducing tube
LTI, 7.22 g (27.0) in a 0 ml two-necked flask.
mmol), 1,1,1,3,3,3-hexafluoroisopropanol 14.9 g (88.8 mmol) and dibutyldichlorotin 12.0 mg (0.04 mmol) were charged, and at 70 ° C. for 6 hours under a nitrogen atmosphere. It was made to react. The reaction was terminated by confirming that the absorption of the isocyanate group disappeared by IR. By the above reaction, 20.8 g of a waxy white solid product was obtained at room temperature.

(Identification analysis) ¹ H-NMR (DMSO-d ₆ ) δ (ppm): 1.
32-1.64 (m, 4H), 1.67-1.90
(M, 2H), 3.04 to 3.21 (m, 2H), 3.
40-3.47 (m, 2H), 4.10-4.28
(M, 3H), 5.80 to 5.92 (m, 3H), 7.
73 to 7.80 (bs, 1H), 7.97 (t, 1H,
J = 5.74 Hz), 8.23 (d, 1H, J = 3.9)
0 Hz) FT-IR (NaCl plate) ν (cm ^-1 ): 3462
(Amide NH stretch), 2976 to 3074 (aliphatic C
-H stretch), 1734 (ester and amide C = O stretch), no absorption of -N = C = O near 2270 cm- ¹ .

Elemental analysis: Calculated value (%) Analytical value (%) Relative error (%) C 31.14 31.65 +1.64 H 2.48 2.52 +1.61 N 5.45 5.57 +2. From the above analysis, it was confirmed that the obtained compound was 1,1,1,3,3,3,3 in which all three isocyanate groups of LTI were blocked with 1,1,1,3,3,3-hexafluoroisopropanol. -Identified as hexafluoroisopropanol block LTI.

Example 4 (2-pyrrolidone block LTI
Synthesis of) using the same apparatus as in Example 1, LTI, 81.0 g
(0.30 mol), 2-pyrrolidone 81.2 g (0.
95 mol) and 0.28 g of dibutyldichlorotin
(0.41 mmol) was charged, and under a nitrogen atmosphere, 70 ° C.
And reacted for 40 hours. The reaction was terminated by confirming that the absorption of the isocyanate group disappeared by IR. By the above reaction, 161 g of a pale yellow viscous liquid product was obtained at room temperature.

(Identification analysis) ¹ H-NMR (CDCl ₃ ) δ (ppm): 1.38
~ 1.50 (m, 2H), 1.52 to 1.64 (m, 2H)
H), 1.72 to 2.10 (m, 8H), 2.52
2.77 (m, 6H), 3.22 to 3.35 (m, 2
H), 3.51 to 3.68 (m, 2H), 3.75 to
3.91 (m, 6H), 4.16 to 4.43 (m, 2
H), 4.48 to 4.56 (m, 1H), 8.33 to
8.43 (bs, 1H), 8.56 to 8.67 (bs,
1H), 8.82 (d, 1H, J = 7.56Hz) FT-IR (NaCl plate) ν (cm ^-1 ): 3301
(Amide NH stretch), 2949 (aliphatic CH stretch), 1685, 1711 (ester and amide C = O)
(Expansion and contraction), no absorption of -N = C = O near 2270 cm ^-1

Elemental analysis: Calculated value (%) Analytical value (%) Relative error (%) C 52.87 51.41 -2.76 H 6.56 6.64 +1.22 N 16.08 15.81- 1.68 From the above analysis, the obtained compound was identified as a 2-pyrrolidone block LTI in which all three isocyanate groups of LTI were blocked with 2-pyrrolidone.

Example 5 (2-piperidinone block LT
Synthesis of I) Using the same apparatus as in Example 3, LTI, 4.00 g (1
5.0 mmol), 2-piperidinone 4.53 g (4
5.7 mmol), dibutyl dichlorotin 13.9 mg
(0.046 mmol) and 12 ml of toluene were charged and reacted at 80 ° C. for 14 hours under a nitrogen atmosphere. IR
After confirming that the absorption of the isocyanate group had disappeared, the reaction was terminated. The solvent was distilled off under reduced pressure to obtain 8.57 g of a pale yellow viscous liquid product at room temperature.

(Identification analysis) ¹ H-NMR (CDCl ₃ ) δ (ppm): 1.34
~ 1.62 (m, 4H), 1.70 to 1.99 (m, 1
4H), 2.46 to 2.60 (m, 6H), 3.22 to
3.35 (m, 2H), 3.51 to 3.65 (m, 2
H), 3.70 to 3.83 (m, 6H), 4.16 to
4.34 (m, 2H), 4.45 to 4.54 (m, 2)
H), 9.30-9.40 (bs, 1H), 9.53-
9.62 (bs, 1H), 9.80 (d, 1H, J =
7.08 Hz) FT-IR (KBr) ν (cm ^-1 ): 3263 (amide NH stretch), 2874 to 2947 (aliphatic CH stretch), 1625 to 1743 (ester and amide C = O).
(Stretching), no absorption of -N = C = O near 2270 cm ^-1

Elemental analysis: Calculated value (%) Analytical value (%) Relative error (%) C 55.11 54.18 −1.69 H 7.47 7.27 −2.68 N 14.83 14.44 -2.63 From the above analysis, the obtained compound was identified as a 2-piperidinone block LTI in which all three isocyanate groups of LTI were blocked with 2-piperidinone.

Example 6 (dibutylamine block LTI
Synthesis of), using the same apparatus as in Example 1, LTI, 80.0 g
(0.30 mol) and 80 ml of toluene were charged, and 117 g of dibutylaniline while cooling with water under a nitrogen atmosphere.
(0.90 mol) was added dropwise over 1 hour. After dripping,
The water cooling was stopped, and the reaction was further continued for 1 hour. After confirming that the absorption of the isocyanate group disappeared by IR, the reaction was terminated. The solvent was distilled off under reduced pressure to obtain 191 g of a pale yellow viscous liquid product at room temperature.

(Identification analysis) ¹ H-NMR (CDCl ₃ ) δ (ppm): 0.88
~ 0.97 (m, 18H), 1.22 to 1.58 (m,
28H), 1.61-1.87 (m, 2H), 3.10
Up to 3.26 (m, 14H), 3.32 to 3.63 (m,
2H), 4.17 to 4.39 (m, 4H), 4.79.
(D, 1H, J = 7.32 Hz), 5.18 (t, 1
H, J = 5.62 Hz) FT-IR (NaCl plate) ν (cm ⁻¹ ): 3340
(Amide NH stretching), 2879-2974 (aliphatic C)
-H stretch), 1730 (ester and amide C = O stretch), no absorption of -N = C = O near 2270 cm- ¹ .

Elemental analysis: Calculated value (%) Analytical value (%) Relative error (%) C 64.42 63.18 -1.92 H 10.77 10.69 +0.74 N 12.83 12.45- 2.96 From the above analysis, the obtained compound was identified as dibutylamine blocked LTI in which all three isocyanate groups of LTI were blocked with dibutylamine.

Example 7 (Synthesis of N-hydroxysuccinimide block LTI) Using the same apparatus as in Example 3, LTI, 2.00 g
(7.5 mmol), N-hydroxysuccinimide 2.70 g (23.5 mmol), dibutyldichlorotin 7.2 mg (0.024 mmol) and THF, 30.
ml was charged and refluxed for 14 hours under a nitrogen atmosphere. IR
After confirming that the absorption of the isocyanate group had disappeared, the reaction was terminated. The solvent was distilled off under reduced pressure to obtain 4.36 g of a white solid product at room temperature.

(Identification analysis) ¹ H-NMR (DMSO-d ₆ ) δ (ppm): 1.
30-1.90 (m, 6H), 2.76 (s, 8H),
2.77 (s, 4H), 3.33 to 3.42 (m, 2
H), 3.62 to 3.68 (m, 2H), 4.05
4.17 (m, 2H), 4.19 to 4.28 (m, 1
H), 8.25 (t, 1H, J = 5.49 Hz), 8.
42 (t, 1H, J = 5.62 Hz), 8.79 (d,
1H, J = 7.81 Hz) FT-IR (KBr) ν (cm ^-1 ): 3340 (amide NH stretch), 2871-3018 (aliphatic CH stretch), 1734, 1778 (ester and amide C). = O
(Expansion and contraction), no absorption of -N = C = O near 2270 cm ^-1

Elemental analysis: Calculated value (%) Analytical value (%) Relative error (%) C 45.10 44.93 −0.38 H 4.77 4.90 +2.73 N 13.72 13.97 +1 0.82 From the above analysis, the obtained compound was identified as N-hydroxysuccinimide block LTI in which all three isocyanate groups of LTI were blocked with N-hydroxysuccinimide.

Example 8 (Synthesis of 2-mercaptothiazoline block LTI) 20 equipped with a thermometer, a Dimroth condenser tube and a nitrogen introduction tube
In a 0 ml four-necked flask, LTI, 30.0 g (0.11
2mol), 2-mercaptothiazoline 40.2g
(0.337 mol), dibutyldichlorotin 0.51
g (1.67 mmol) and 30 ml of toluene were charged and reacted at 80 ° C. for 45 hours under a nitrogen atmosphere. IR
After confirming that the absorption of the isocyanate group had disappeared, the reaction was terminated. The solvent was distilled off under reduced pressure to obtain 70.0 g of a brown viscous liquid product at room temperature.

(Identification analysis) ¹ H-NMR (CDCl ₃ ) δ (ppm): 1.38
~ 1.54 (m, 2H), 1.54 to 1.73 (m, 2)
H), 1.76 to 2.00 (m, 2H), 3.20 to
3.40 (m, 8H), 3.52 to 3.69 (m, 2
H), 4.23 to 4.34 (m, 2H), 4.48 to
4.58 (m, 1H), 4.63 to 4.75 (m, 6)
H), 9.73-9.84 (bs, 1H), 9.97-
10.08 (bs, 1H), 10.28 (d, 2H, J
= 7.33 Hz) FT-IR (NaCl plate) ν (cm ⁻¹ ): 3188
(Amide NH stretch), 2860 to 3037 (aliphatic C
-H stretch), 1699, 1741 (ester and amide C = O stretch), no absorption of -N = C = O near 2270 cm ^-1 .

Elemental analysis: Calculated value (%) Analytical value (%) Relative error (%) C 35.98 36.18 +0.56 H 4.70 4.77 +1.49 N 13.99 13.64 -2 From the above analysis, the obtained compound was identified as a 2-mercaptothiazoline block LTI in which all three isocyanate groups of LTI were blocked with 2-mercaptothiazoline.

Example 9 (Synthesis of 1,3-diethylurea block LTI) Using the same apparatus as in Example 3, LTI, 2.00 g
(7.5 mmol), 1,3-diethylurea 2.75 g
(23.7 mmol), dibutyldichlorotin 7.2 m
g (0.024 mmol) and 30 ml of ethyl acetate were charged, and the mixture was refluxed for 16 hours under a nitrogen atmosphere. The reaction was terminated by confirming that the absorption of the isocyanate group disappeared by IR. The solvent was distilled off under reduced pressure to obtain 4.80 g of a pale yellow viscous liquid product at room temperature.

(Identification analysis) ¹ H-NMR (CDCl ₃ ) δ (ppm): 1.07
~ 1.29 (m, 18H), 1.35 to 1.49 (m,
2H), 1.53 to 1.65 (m, 2H), 1.72 to
1.94 (m, 2H), 3.09 to 3.37 (m, 10
H), 3.40 to 3.65 (m, 2H), 3.68 to
3.86 (m, 4H), 4.17 to 4.46 (m, 3
H), 6.79 (bs, 1H), 6.92 (bs, 1)
H), 7.09 (bs, 1H), 7.44 (bs, 1)
H), 7.54 (bs, 1H), 7.96 (bs, 1)
H) FT-IR (NaCl plate) ν (cm ^-1 ): 3325
(Amide NH stretch), 2874-2935 (aliphatic C
-H stretch), 1637 to 1743 (ester and amide C = O stretch), no absorption of -N = C = O near 2270 cm ^-1 .

Elemental analysis: Calculated value (%) Analytical value (%) Relative error (%) C 50.72 50.04 −1.34 H 8.02 8.20 +2.24 N 20.47 19.91 − 2.74 From the above analysis, the obtained compound was identified as 1,3-diethylurea block LTI in which all three isocyanate groups of LTI were blocked with 1,3-diethylurea.

Comparative Example 1 (Synthesis of Methyl Isobutyl Ketoxime Block HDI Isocyanurate) Using the same apparatus as in Example 3, an HDI isocyanurate body [Nippon Polyurethane Co., Ltd., trade name "Coronate H"
L "NV 75%, solvent; ethyl acetate] 6.00 g (8.
92 mmol) and 4.5 ml of toluene were charged, and MIBK, 3.13 g (2
(7.2 mmol) was added dropwise over 30 minutes, and further 70 ° C.
For 3 hours. The reaction was terminated by confirming that the absorption of the isocyanate group disappeared by IR. 7. The product was obtained as a pale yellow viscous liquid at room temperature by distilling off the solvent under reduced pressure.
6 g were obtained.

(Identification analysis) ¹ H-NMR (CDCl ₃ ) δ (ppm): 0.87
~ 0.99 (m, 18H), 1.26 ~ 1.62 (m,
24H), 1.82 to 2.17 (m, 18H), 3.1.
4 (d, 6H, J = 6.10 Hz), 3.99 (bs,
6H), 6.34 (bs, 3H) FT-IR (NaCl plate) ν (cm ^-1 ): 3344
(Amide NH stretch), 2860 to 2970 (aliphatic C)
-H stretching), 1687, 1718 (amide C = O stretching), no absorption of -N = C = O near 2270 cm ^-1 .

Elemental analysis: Calculated value (%) Analytical value (%) Relative error (%) C 56.45 55.38 −1.90 H 8.29 8.45 +1.93 N 16.46 16.05 − 2.49 From the above analysis, the obtained compound was identified as MIBKO-blocked HDI isocyanurate in which all three isocyanate groups of HDI isocyanurate were blocked with MIBKO.

Comparative Example 2 (Synthesis of Phenol Block HDI Isocyanurate) Using the same apparatus as in Example 2, an HDI isocyanurate body [manufactured by Nippon Polyurethane Co., Ltd., trade name "Coronate H"
L "NV 75%, solvent; ethyl acetate] 68.2 g (0.
101 mol), phenol 40.0 g (0.425 m
ol), dibutyldichlorotin 0.12 g (0.41 m
mol) and 160 ml of toluene were charged, and the mixture was reacted at 70 ° C. for 9 hours under a nitrogen atmosphere. The reaction was terminated by confirming that the absorption of the isocyanate group disappeared by IR. The solvent was distilled off under reduced pressure to obtain 110 g of a pale yellow viscous liquid product at room temperature.

(Identification analysis) ¹ H-NMR (CDCl ₃ ) δ (ppm): 1.20
˜1.75 (m, 24H), 3.24 (q, 6H, J =
6.59 Hz), 3.88 (t, 6H, J = 7.32H)
z), 5.12 (bs, 3H), 7.01 to 7.40.
(M, 15H) FT-IR (NaCl plate) ν (cm ^-1 ): 3238
(Amide NH stretch), 2860 to 3066 (aliphatic C
-H stretch), 1689, 1716 (amide C = O stretch), no absorption of -N = C = O near 2270 cm ^-1 .

Elemental analysis: Calculated value (%) Analytical value (%) Relative error (%) C 64.11 62.16 −3.04 H 6.92 6.8 1.1.5 −1.59 N 10.68 10.98 2.81 From the above analysis, the obtained compound was identified as a phenol block HDI isocyanurate in which all three isocyanate groups of HDI isocyanurate were blocked with phenol.

Comparative Example 3 (2-piperidinone block HD
Synthesis of I isocyanurate) An HDI isocyanurate body [manufactured by Nippon Polyurethane Co., Ltd., trade name "Coronate H"] was prepared using the same apparatus as in Example 3.
L "NV 75%, solvent; ethyl acetate] 6.00 g (8.
92 mmol), 2.70 g of 2-piperidinone (27.
2 mmol), dibutyldichlorotin 8.3 mg (0.
027 mmol) and toluene 12.4 ml,
The reaction was carried out at 80 ° C. for 6.5 hours under a nitrogen atmosphere. The reaction was terminated by confirming that the absorption of the isocyanate group disappeared by IR. The solvent was distilled off under reduced pressure to obtain 7.2 g of a pale yellow viscous liquid product at room temperature.

(Identification analysis) ¹ H-NMR (CDCl ₃ ) δ (ppm): 1.22
~ 1.60 (m, 24H), 1.72-1.88 (m,
12H), 2.30 to 2.40 (m, 6H), 3.13.
(Bs, 6H), 3.22 to 3.36 (m, 6H),
3.98 (bs, 6H), 6.01 (bs, 3H) FT-IR (NaCl plate) ν (cm ^-1 ): 3292
(Amide NH stretch), 2860 to 2935 (aliphatic C
-H stretching), 1662, 1700 (amide C = O stretching), no absorption of -N = C = O near 2270 cm ^-1 .

Elemental analysis: Calculated value (%) Analytical value (%) Relative error (%) C 58.41 57.24 −2.00 H 7.92 8.06 +1.77 N 15.72 15.36 − 2.29 From the above analysis, the obtained compound was identified as 2-piperidinone-blocked HDI isocyanurate in which all three isocyanate groups of HDI isocyanurate were blocked with 2-piperidinone.

[0076]

EFFECTS OF THE INVENTION According to the present invention, the blocking agent dissociation ability at a lower temperature than that of the conventionally used blocked aliphatic isocyanate compound, and the baking temperature when used as a curing agent in a coating composition is improved. It is possible to provide a blocked aliphatic isocyanate compound which can reduce the cost, reduce the cost by shortening the baking time, improve the productivity, and reduce the pollution.

Claims (8)

[Claims] 1. A compound of the general formula (I) (In the formula, R ¹ , R ² and R ³ are the same or different,
Represents a residue of an active hydrogen compound). 2. The active hydrogen compound is an alcohol, a phenol, a thiol, an oxime, an amide, an amine, an imine, an imide or a urea.
The blocked isocyanate compound described. 3. An active hydrogen compound represented by the general formula (II): (Wherein R ⁴ represents substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl or substituted or unsubstituted heteroaryl, and X represents O or S). The blocked isocyanate compound according to claim 1, which is an alcohol, a phenol or a thiol represented. 4. The active hydrogen compound is represented by the general formula (III): (In the formula, R ⁵ and R ⁶ are the same or different and each represents a substituted or unsubstituted alkyl, a substituted or unsubstituted cycloalkyl, a substituted or unsubstituted aryl or a substituted or unsubstituted heteroaryl) The blocked isocyanate compound according to claim 1, which is an oxime. 5. The active hydrogen compound is represented by the general formula (IV): (In the formula, R ⁷ represents hydrogen, alkyl, cycloalkyl or amino, R ⁸ and R ⁹ are the same or different, and are hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or Represents unsubstituted aryl or substituted or unsubstituted heteroaryl, or R ⁸ and R ⁹ together represent lower alkylene)
The blocked isocyanate compound according to claim 1, which is an amide represented by: 6. The active hydrogen compound is represented by the general formula (V): (In the formula, R ¹⁰ and R ¹¹ are the same or different and each represents a substituted or unsubstituted alkyl, a substituted or unsubstituted cycloalkyl, a substituted or unsubstituted aryl or a substituted or unsubstituted heteroaryl, or R The blocked isocyanate compound according to claim 1, which is an amine or imine represented by ( ¹⁰ and R ¹¹ together represent lower alkylene) or a substituted or unsubstituted carbazole. 7. The active hydrogen compound is represented by the general formula (VI): (In the formula, R ¹² and R ¹³ are the same or different and represent a substituted or unsubstituted alkyl or a substituted or unsubstituted cycloalkyl, or R ¹² and R ¹³ together represent a lower alkylene; Is a imide represented by hydrogen or hydroxy), and the blocked isocyanate compound according to claim 1. 8. An active hydrogen compound is represented by the general formula (VII): (In the formula, R ¹⁴ , R ¹⁵ and R ¹⁶ are the same or different,
Hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl or substituted or unsubstituted heteroaryl, Z
Is a urea represented by the formula (1) or (2), and the blocked isocyanate compound according to claim 1.