JPH07330860A - Polyisocyanate composition - Google Patents

Abstract

PURPOSE:To obtain a polyisocyanate composition composed of a polyisocyanate mixture obtained from an aliphatic diisocyanate and an aliphatic primary monoalcohol and a low poiar organic solvent, having a low viscosity even in the case of a high solid matter content and excellent in long-term storage stability. CONSTITUTION:This polyisocyanate composition is composed of (A) a mixture containing a polyisocyanurate synthesized by conducting a urethanization reaction between (i) an aliphatic diisocyanate composed of hexamethylene diisocyanate or a mixture of hexamethylene diisocyanate and isophorone diisocyanate and (ii) a 6 to 9C aliphatic monoalcohol such as 1-hexanol or 2-ethyl-1-hexanol and subsequently conducting a reaction in the presence of an isocyanuration catalyst such as tetramethylammonium, exhibiting 50 to 1400mPa.S viscosity at 25 deg.C in a state in which the solvent and the component (i) are substantially not contained and having an isocyanurate structure and a polyisocyanurate having an isocyanurate structure and a poly isocyanurate having an allophanate structure and (B) a low polar organic solvent such as methylcyclohexane.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a polyisocyanate composition useful as a curing agent for paints, inks, adhesives and the like.

[0002]

2. Description of the Related Art Among the polyisocyanate compositions obtained from hexamethylene diisocyanate (hereinafter referred to as HDI) and isophorone diisocyanate (hereinafter referred to as IPDI), isocyanurate type polyisocyanate has weather resistance, chemical resistance, abrasion resistance, etc. It is widely used as paints, inks, adhesives, etc. to show excellent performance. However, isocyanurate type polyisocyanate has a high viscosity and the polarity of the isocyanurate structure is high. Therefore, when it is actually used, it is a highly toxic organic solvent such as ethyl acetate, butyl acetate, toluene and xylene. However, there is a problem in that the working environment is significantly deteriorated due to the evaporation of the solvent, and the base coating film is attacked in the case of repair work.

As a method for obtaining a polyisocyanate mixture having excellent solubility in a low-polarity organic solvent which solves the problem, a diisocyanate and a diol having 10 to 40 carbon atoms described in Japanese Patent Publication No. 62-51968 are used as an isocyanate. A polyisocyanate composition having an isocyanurate structure obtained by reacting in the presence of a nurate forming catalyst has been proposed.

Further, JP-A-2-105812 proposes a polyisocyanate mixture having an isocyanurate structure obtained by reacting a diisocyanate with an ester diol in the presence of an isocyanurate-forming catalyst. Further, in Japanese Patent Laid-Open No. 2-250872,
A polyisocyanate mixture having an isocyanurate structure obtained by reacting a diisocyanate with a monoalcohol having 10 to 50 carbon atoms in the presence of an isocyanurate-forming catalyst, and a method for producing the same have been proposed.

Furthermore, in the polyisocyanate mixture proposed in JP-A-4-306218, an aliphatic diisocyanate and an aliphatic monoalcohol having 6 to 9 carbon atoms are subjected to urethanization reaction, and then the isocyanurate-forming catalyst is used. A polyisocyanate mixture having an isocyanurate structure obtained by reacting in the presence of a polyisocyanate has been proposed.

However, Japanese Patent Publication No. 62-51968, Japanese Unexamined Patent Publication No. 2-105812 and Japanese Unexamined Patent Publication No. 2-2.
The polyisocyanate mixtures proposed in Japanese Patent No. 50872 have high viscosities, need to be dissolved in a large amount of organic solvents when used, and have a problem of releasing a large amount of organic solvents into the atmosphere. On the other hand, the polyisocyanate mixture proposed in JP-A-4-306218 achieves excellent solubility and low viscosity in low polar organic solvents.

Further, in JP-A-5-222007, for the purpose of lowering the viscosity, a monoalcohol having 6 to 9 carbon atoms is subjected to a urethanization reaction or at the same time as the urethanization reaction in the presence of an isocyanurate-forming catalyst. There has been proposed a method for producing a polyisocyanate mixture having an isocyanurate structure obtained by reacting with. However, this manufacturing method is almost the same as the technique proposed in Japanese Patent Laid-Open No. 4-306218.

On the other hand, although the object of the invention is different, in Japanese Patent Publication No. 4-13350, it is obtained by reacting an aliphatic diisocyanate with an aliphatic monoalcohol having 6 to 9 carbon atoms in the presence of an isocyanurate-forming catalyst. A method for producing a polyisocyanate mixture having an isocyanurate structure is proposed. However, in the present invention, since the urethanization reaction and the isocyanurate reaction are simultaneously performed, the obtained polyisocyanate mixture has insufficient solubility in a low polar organic solvent.

[0009]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a polyisocyanate composition containing a low polar organic solvent which has a high solid content and a low viscosity and is excellent in long-term storage stability.

[0010]

As a result of intensive studies, the present inventors have found that a polyisocyanate mixture obtained from an aliphatic diisocyanate and a specific aliphatic monoalcohol has a low viscosity and a low polar organic solvent. The present inventors have completed the present invention by finding that the contained polyisocyanate composition has excellent long-term storage stability.

That is, the present invention relates to HDI or HDI.
A solvent and the above aliphatic compound obtained by urethane-converting an aliphatic diisocyanate consisting of a mixture of benzene and IPDI with an aliphatic primary monoalcohol having 6 to 9 carbon atoms and then reacting it in the presence of an isocyanurate-forming catalyst. Viscosity at 25 ° C without diisocyanate is 5
The present invention relates to a polyisocyanate composition consisting of a polyisocyanate having an isocyanurate structure and a polyisocyanate having an allophanate structure at 0 to 1400 mPa · s, and a polyisocyanate composition comprising a low polar organic solvent.

The alcohol used in the polyisocyanate mixture in the present invention is an aliphatic primary monoalcohol having 6 to 9 carbon atoms. For example 1-hexanol,
1-heptanol, 1-octanol, 2-ethyl-1
-Hexanol and the like. Use of an aliphatic monoalcohol having less than 6 carbon atoms is not preferable because the solubility of the polyisocyanate mixture in a low polar organic solvent is lowered. If the carbon number exceeds 9, the viscosity of the polyisocyanate mixture increases, which is not preferable. With an aliphatic monoalcohol having 6 to 9 carbon atoms, a polyisocyanate mixture having low viscosity and excellent solubility in a low polar solvent can be obtained. Among them, the polyisocyanate mixture obtained from the primary monoalcohol has a feature that it is also excellent in long-term storage stability in a low polar organic solvent.

The amount of the component derived from the aliphatic monoalcohol contained in the polyisocyanate mixture in the present invention is 5 to 30% by weight, preferably 10 to 25% by weight. If it is less than 5% by weight, the solubility in a low-polar organic solvent is lowered, which is not preferable. When it exceeds 30% by weight, the isocyanate group content (hereinafter, NCO group content)
However, this is not preferable in terms of resin design because it is significantly reduced. The component derived from the aliphatic monoalcohol has the following structure. R-O- (In the formula, R represents a hydrocarbon residue having 6 to 9 carbon atoms.)

The polyisocyanate mixture in the present invention is obtained by subjecting an aliphatic diisocyanate and an aliphatic monoalcohol to a urethanization reaction and then reacting them in the presence of an isocyanurate-forming catalyst. The polyisocyanate having an isocyanurate structure and an allophanate are obtained. It is obtained as a mixture of a polyisocyanate having a structure and a polyisocyanate having an isocyanurate structure and an allophanate structure in one molecule. On the other hand, a polyisocyanate mixture obtained by reacting an aliphatic diisocyanate with an aliphatic monoalcohol in the presence of an isocyanurate-forming catalyst and simultaneously performing a urethanization reaction and an isocyanurate-forming reaction has an allophanate structure. Almost no polyisocyanate was obtained, and instead, a polyisocyanate having a urethane structure obtained by reacting one molecule of an aliphatic diisocyanate with one molecule of a monoalcohol and a polyisocyanate having an isocyanurate structure, and an isocyanurate structure and a urethane structure in one molecule. Obtained as a mixture of polyisocyanates having. This polyisocyanate mixture has insufficient solubility in low polar organic solvents.

The reaction temperature for urethanization is 40 to 200 ° C.
Selected from the range. If the temperature is lower than 40 ° C, the reaction rate is slow,
It is not preferable because it takes a great amount of time to form a urethane. Two
If the temperature exceeds 00 ° C, coloring and side reactions occur, which is not preferable. The isocyanurate-forming catalyst referred to in the present invention is one that preferentially produces isocyanurate from 3 molecules of HDI, and examples thereof include tetramethylammonium, monoethyltrimethylammonium, diethyldimethylammonium, tetraethylammonium, tetrabutylammonium and the like. Hydroxides of tetraalkylammonium and weak organic acid salts such as trimethylhydroxypropylammonium, trimethylhydroxyethylammonium, triethylhydroxypropylammonium, triethylhydroxyethylammonium, etc. Hydroxylammonium hydroxides and weak organic acids such as acetic acid, caproic acid , Alkali metal salts of alkylcarboxylic acids such as octylic acid and myristic acid, for example, the above-mentioned alkylcarboxylates. Tin of phosphate, zinc,
Examples thereof include metal salts of lead and the like, for example, one of aminosilyl group-containing compounds such as hexamethyldisilazane and the like, or a mixture thereof.

The amount of the isocyanurate-forming catalyst added is 0.0005 to 1% by weight based on the aliphatic diisocyanate,
It is preferably selected from the range of 0.001 to 0.05% by weight. If it is less than 0.0005% by weight, the reaction does not proceed or the reaction rate is extremely slow, which is not preferable. 1
When it exceeds the weight%, it is not preferable because it becomes very difficult to control the reaction.

The reaction temperature for the isocyanurate formation is 40 to 1
It is selected from the range of 60 ° C. If it is lower than 40 ° C., the reaction rate is slow and the amount of catalyst added is large, which is not preferable from an economical point of view. If it exceeds 160 ° C, coloring or side reaction occurs, which is not preferable. The conversion of the reaction can be determined according to the purpose of the polyisocyanate mixture, but usually,
15-60% by weight is preferred. If it is less than 15% by weight, it is not preferable from the economical viewpoint. If it exceeds 60% by weight, the viscosity of the polyisocyanate mixture increases, which is not preferable. The conversion rate can be obtained from the following formula. (Conversion rate = polyisocyanate mixture weight / charged weight × 100%) The progress of the reaction can be traced by measuring the NCO group content of the reaction solution, infrared spectroscopic measurement, refractive index measurement and the like. When the reaction reaches the target conversion rate, one or more catalyst poisons such as hydrochloric acid, sulfuric acid, sulfuric acid ester, phosphoric acid and phosphoric acid ester are added to stop the reaction.

A solvent may or may not be used in the reaction system. However, when using a solvent, it is necessary to select a solvent having no reaction activity with respect to the isocyanate group. Examples of the solvent include aromatic hydrocarbons such as toluene and xylene and esters such as ethyl acetate and butyl acetate,
Examples include low-polarity organic solvents such as mineral spirit and turpentine.

After stopping the reaction, if necessary, the deactivated catalyst is removed by filtration, and then the unreacted aliphatic diisocyanate and the solvent are removed to obtain a polyisocyanate mixture. The removal of the aliphatic diisocyanate and the solvent is performed by, for example, a thin film evaporation method or a solvent extraction method. The aliphatic diisocyanate used may be added with additives such as antioxidants and ultraviolet absorbers.

The viscosity of the polyisocyanate mixture according to the present invention at 25 ° C. is 50 to 1400 mPa · s in the state that the solvent and the aliphatic diisocyanate are not substantially contained.
s. If it is less than 50 mPa · s, there is a drawback that the polyisocyanate having an isocyanurate structure in the polyisocyanate mixture is remarkably reduced and the curing rate is remarkably lowered. If it exceeds 1400 mPa · s, the viscosity reduction is insufficient and the amount of organic solvent cannot be reduced during use. Incidentally, the state of substantially not containing the solvent and the aliphatic diisocyanate means that the solvent and the diisocyanate may be contained to the extent that the viscosity of the polyisocyanate mixture is not affected, and the As a rough guide, it means that a content of about 1% by weight or less is allowed.

The low-polarity organic solvent referred to in the present invention is an organic solvent of aliphatic, alicyclic and aromatic hydrocarbon type, having a low solubilizing power in the range of aniline point 10 to 70 ° C., and low toxicity. It refers to a solvent and also refers to a mixed organic solvent containing these low polar organic solvents as a main component. Examples of the low-polarity organic solvent used in the present invention include methylcyclohexane (aniline point 40 ° C.), ethylcyclohexane (aniline point 44 ° C.), mineral spirit (aniline point 56).
C.), turpentine oil (aniline point 20 ° C.), etc., House (commercially available from Shell Chemical Co., aniline point 15 ° C.), Swasol 310 (Maruzen Chemical Co., aniline point 16 ° C.), which is generally marketed as petroleum hydrocarbons, Essonaphtha No. 6
(Manufactured by Exxon Chemical Co., aniline point 43 ° C.), Loose (manufactured by Shell Chemical Co., aniline point 44 ° C.), pegazole 3040
(Manufactured by Mobil Oil, aniline point 55 ° C.) and the like.

As the method for obtaining the polyisocyanate composition of the present invention, there are a method of mixing the polyisocyanate mixture of the present invention with a low polar organic solvent at an arbitrary ratio, and a method of using the low polar organic solvent as a reaction solvent. The polyisocyanate composition of the present invention can exhibit excellent coating film physical properties when used as a curing agent for polyols. Examples of usable polyols include acrylic polyols, polyester polyols, epoxy polyols, alkyd polyols, fluorine polyols and urethane polyols.

Various additives used in the art, such as catalysts, pigments, leveling agents, antioxidants, ultraviolet absorbers, light stabilizers, plasticizers, surface active agents, etc., depending on the purpose and application. It is also possible to mix and use. The polyisocyanate composition of the present invention has excellent long-term storage stability, as compared with polyisocyanate mixtures excellent in solubility in low polar organic solvents obtained by conventional techniques and those obtained from low polar organic solvents. In addition to achieving high solid content with the same viscosity, it is possible to suppress the amount of organic solvent released into the atmosphere. Further, compared to the conventional polyisocyanate composition using a strongly polar organic solvent, not only can the working environment be significantly improved, but also in the case of repair work, overcoating is possible without damaging the underlying coating film. Become. Furthermore, the polyisocyanate composition of the present invention is excellent in compatibility and reactivity with various polyols such as acrylic polyol, polyester polyol, epoxy polyol, alkyd polyol, and fluoropolyol, and therefore, paints, adhesives, inks,
It can be used as a curing agent for coating materials, casting materials, elastomers, foams, and as a raw material for plastic materials.

[0024]

EXAMPLES The measuring methods used in the present invention are shown below. NC
The O group content was determined by back titration with hydrochloric acid after neutralizing the isocyanate group with an excess of amine. The viscosity was measured at 25 ° C. and 60 rpm with a digital viscometer (Tokyo Keiki Co., Ltd. DVM-B type). The infrared absorption spectrum (IR) was performed by a rock salt plate coating method using a Fourier transform infrared spectrophotometer (FT / IR-5M type manufactured by JASCO Corporation). ¹ H-NMR was performed using a nuclear magnetic resonance apparatus (manufactured by JEOL Ltd., solvent: CDCl ₃ ).

[0025]

Example 1 In a four-necked flask equipped with a stirrer, a thermometer, and a cooling tube, 500 g of HDI and 1-octanol 20 were added.
g was charged and the urethanization reaction was completed at 80 ° C. for 2 hours with stirring. Next, 0.02 g of tetramethylammonium capryate as an isocyanurate-forming catalyst was added at 60 ° C. After 4 hours, 0.1 g of phosphoric acid was added to stop the reaction when the conversion of polyisocyanate to 24% was measured by measuring the isocyanate group content and the refractive index of the reaction solution. The increase in refractive index immediately after the addition of the catalyst poison was 0.01.

After removing the precipitate by filtration, the first time 0.3 Tor. (155
C.) 2nd time 0.2 Tor. Unreacted H at (145 ° C)
The DI was removed. The resulting polyisocyanate mixture was a pale yellow, transparent liquid with a yield of 122 g and a viscosity of 4
The isocyanate group content was 50 mPa · s and 21.0% by weight. The amount of the constituent component derived from 1-octanol contained in this was 16.4%. When the IR of this isocyanate mixture was measured, a peak of isocyanurate groups was found at 1688 cm ^-1 . ¹ H-NMR
Was measured, a peak of a proton directly bonded to the nitrogen atom of the allophanate structure was observed near δ = 8.6 ppm. This polyisocyanate mixture was diluted to 75% concentration with a low-polar organic solvent house (Shell Chemical, aniline point 15 ° C.) to obtain 192 g of a transparent polyisocyanate composition.

This polyisocyanate composition has a viscosity of 3
3mPa · s, the isocyanate group content is 15.7% by weight, the solubility in the house is 1000% or more at 20 ° C, and the viscosity after storage at 50 ° C for 1 month is 33mP.
The a · s and NCO group content was 15.7% by weight, and no change was observed.

[0028]

Example 2 The same apparatus as in Example 1 was charged with 500 g of HDI.
And 40 g of 1-octanol were charged, and the mixture was stirred at 80 ° C for 2
The urethane reaction was carried out for an hour to complete the urethane reaction.
Then, at 80 ° C., 0.03 g of tetramethylammonium capryate as an isocyanurate-forming catalyst was added.
After 4 hours, the conversion to polyisocyanate was found to be 36% by measuring the isocyanate group content and the refractive index of the reaction solution.
Then, 0.15 g of phosphoric acid was added to stop the reaction. The increase in refractive index immediately after the addition of the catalyst poison was 0.011.

Then, purification was carried out in the same manner as in Example 1.
The obtained polyisocyanate mixture was a pale yellow, transparent liquid, and the yield was 191 g, the viscosity was 420 mPa · s, and the isocyanate group content was 16.8 wt%. The amount of the constituent components derived from 1-octanol contained in this was 21%. When the IR of this isocyanate mixture was measured, a peak of isocyanurate groups was found at 1688 cm ^-1 . ^{When 1} H-NMR is measured, δ = 8.6.
A peak of a proton directly bonded to the nitrogen atom of the allophanate structure was observed around ppm. This polyisocyanate mixture is used as a low-polar organic solvent Essonaphtha N.
o. 75% at 6 (manufactured by Exxon Chemical, aniline point 43 ° C)
A transparent polyisocyanate composition 255 diluted to a concentration
g was obtained.

This polyisocyanate composition has a viscosity of 3
0 mPa · s, isocyanate group content is 12.6% by weight, Essonaphtha No. Solubility for 6 is 20 ℃
And the viscosity was 31 mPa · s and the NCO group content was 12.6% by weight, and no change was observed.

[0031]

Example 3 The same apparatus as in Example 1 was charged with 500 g of HDI.
And 2-ethyl-1-hexanol (15 g) were charged, and a urethanization reaction was carried out at 80 ° C. for 2 hours with stirring to complete urethanization. Then, at 80 ° C., tetramethylammonium capryate 0.01 as an isocyanurate-forming catalyst is used.
5 g was added. After 4 hours, 0.06 g of phosphoric acid was added to stop the reaction when the conversion of polyisocyanate to 28% was measured by measuring the isocyanate group content and the refractive index of the reaction solution. The refractive index increase immediately after adding the catalyst poison is
It was 0.011.

Then, purification was carried out in the same manner as in Example 1.
The obtained polyisocyanate mixture is a slightly yellow and transparent.
Liquid, yield 144g, viscosity 550mPa · s,
The cyanate group content was 20.8% by weight. this
Derived from 2-ethyl-1-hexanol contained in
The amount of constituents was 10%. This isocyanate mixture
When the IR of the compound is measured, it is 1688 cm. ^-1On isocyanu
A rate-based peak was seen.¹Measure H-NMR
And δ = around 8.6 ppm nitrogen source of allophanate structure
A peak of protons directly bonded to the offspring was observed. This
Of polyisocyanate mixture of low polar organic solvent
7 with Wazoll 310 (Maruzen Chemical, aniline point 16 ° C)
Transparent polyisocyanate composition 1 diluted to a concentration of 5%
92 g were obtained.

This polyisocyanate composition has a viscosity of 4
0 mPa · s, isocyanate group content is 15.6% by weight, solubility in Swazol 310 is 1 at 20 ° C.
As a result of being stored at 50 ° C. for 1 month, the viscosity was 41 mPa · s, the NCO group content was 15.5 wt%, and no change was observed.

[0034]

Example 4 The same device as in Example 1 was charged with 500 g of HDI.
And 2-ethyl-1-hexanol (50 g) were charged, and the urethanization reaction was completed at 90 ° C. for 2 hours with stirring to complete the urethanization. Then, at 90 ° C., tetramethylammonium capryate 0.03 as an isocyanurate-forming catalyst is used.
g was added. After 4 hours, 0.07 g of phosphoric acid was added to stop the reaction when the conversion to polyisocyanate reached 47% by measuring the isocyanate group content and the refractive index of the reaction solution. The refractive index increase immediately after adding the catalyst poison is
It was 0.015.

Then, purification was carried out in the same manner as in Example 1.
The obtained polyisocyanate mixture is a slightly yellow and transparent.
Liquid, yield 258g, viscosity 410mPa · s,
The cyanate group content was 17.6% by weight. this
Derived from 2-ethyl-1-hexanol contained in
The amount of constituents was 19%. This isocyanate mixture
When the IR of the compound is measured, it is 1688 cm. ^-1On isocyanu
A rate-based peak was seen.¹Measure H-NMR
And δ = around 8.6 ppm nitrogen source of allophanate structure
A peak of protons directly bonded to the offspring was observed. This
Of polyisocyanate mixture of
Nalal Spirit (Kishida Chemical, aniline point 56 ° C)
A transparent polyisocyanate composition diluted to 60% with
430 g of the product was obtained.

This polyisocyanate composition has a viscosity of 1
3mPa · s, the isocyanate group content is 10.6% by weight, the solubility in mineral spirits is 1000% or more at 20 ° C, and the result of storage at 50 ° C for 1 month is:
Viscosity 14 mPa · s, NCO group content is 10.5% by weight
No change was observed.

[0037]

[Embodiment 5] The same device as in Embodiment 1 was charged with 500 g of HDI.
And 30 g of 1-hexanol were charged, and the mixture was stirred at 60 ° C. for 2 hours.
The urethane reaction was carried out for an hour to complete the urethane reaction.
Then, 0.02 g of tetrabutylammonium capryate as an isocyanurate-forming catalyst was added at 50 ° C.
After 4 hours, the conversion to polyisocyanate was 33% by measuring the isocyanate group content and the refractive index of the reaction solution.
Bis- (2-ethylhexyl) phosphate
The reaction was stopped by adding 0.2 g of the ester. The increase in refractive index immediately after the addition of the catalyst poison was 0.011.

Then, purification was carried out in the same manner as in Example 1.
The obtained polyisocyanate mixture was a pale yellow, transparent liquid, the yield was 176 g, the viscosity was 340 mPa · s, and the isocyanate group content was 18.5% by weight. The amount of the constituent component derived from 1-hexanol contained in this was 14%. When the IR of this isocyanate mixture was measured, a peak of isocyanurate groups was found at 1688 cm ^-1 . ^{When 1} H-NMR is measured, δ = 8.6.
A peak of a proton directly bonded to the nitrogen atom of the allophanate structure was observed around ppm. This polyisocyanate mixture is used as a low-polar organic solvent Essonaphtha N.
o. The mixture was diluted with 6 to 90% concentration to obtain 196 g of a transparent polyisocyanate composition.

This polyisocyanate composition has a viscosity of 1
35 mPa · s, isocyanate group content is 16.7
% By weight, Essonaphtha No. Solubility in 6 is 20
As a result of being stored at 50 ° C for 1 month, the viscosity is 137 mPa · s and the NCO group content is 16.8% by weight.
No change was observed.

[0040]

[Sixth Embodiment] 400 g of HDI was added to the same apparatus as in the first embodiment.
And IPDI 100g and 2-ethyl-1-hexanol 2
5 g was charged and the urethanization reaction was completed at 80 ° C. for 2 hours with stirring to complete the urethanization. Then, 0.03 g of tetramethylammonium capryate as an isocyanurate-forming catalyst was added at 60 ° C. After 4 hours, the isocyanate group content and the refractive index of the reaction solution were measured, and when the conversion rate to polyisocyanate reached 25%, 0.2 g of phosphoric acid bis- (2-ethylhexyl) ester was added to carry out the reaction. I stopped. The refractive index increase immediately after adding the catalyst poison is
It was 0.01.

Then, purification was carried out in the same manner as in Example 1.
The obtained polyisocyanate mixture was a pale yellow transparent liquid, the yield was 130 g, the viscosity was 1200 mPa · s,
The isocyanate group content was 21.1% by weight. The amount of constituent components derived from 2-ethyl-1-hexanol contained in this was 14%. When the IR of this isocyanate mixture was measured, a peak of isocyanurate groups was found at 1688 cm ^-1 . ^{When 1} H-NMR was measured, a peak of a proton directly bonded to the nitrogen atom of the allophanate structure was observed near δ = 8.6 ppm.
This polyisocyanate mixture was mixed with Esonanaphtha No. It was diluted to 75% with 6 to obtain 163 g of a transparent polyisocyanate composition.

This polyisocyanate composition has a viscosity of 1
22 mPa · s, isocyanate group content is 15.7
% By weight, Essonaphtha No. Solubility in 6 is 20
It is 500% at 50 ° C, and it has a viscosity of 123 mPa · s and an NCO group content of 15.6% by weight after being stored at 50 ° C for 1 month.
No change was observed.

[0043]

COMPARATIVE EXAMPLE 1 500 g of HDI was added to the same device as in Example 1.
And 12-hydroxystearyl alcohol (50 g) were charged, and the urethanization reaction was completed at 60 ° C. for 2 hours with stirring. Then, at 60 ° C., 0.02 g of tetrabutylammonium capryate as an isocyanurate-forming catalyst was added. After 4 hours, when the conversion of polyisocyanate to 55% was measured by measuring the isocyanate group content and the refractive index of the reaction solution, 0.2 g of phosphoric acid was added.
Was added to stop the reaction. The refractive index increase immediately after the addition of the catalyst poison was 0.015.

Then, purification was carried out in the same manner as in Example 1.
The obtained polyisocyanate mixture was a pale yellow, transparent liquid with a yield of 273 g and a viscosity of 30,000 mPa · s.
s, the isocyanate group content was 16.0% by weight. When the IR of this product was measured, a peak of isocyanurate group was observed at 1688 cm ^-1 . ¹ H-NMR
Was measured, a peak of a proton directly bonded to the nitrogen atom of the allophanate structure was observed near δ = 8.6 ppm. This polyisocyanate composition was diluted to 75% with a low-polar organic solvent, Swazol 310, to obtain 326 g of a transparent polyisocyanate composition.

This polyisocyanate composition has a viscosity of 8
It is extremely high at 20 mPa · s, the isocyanate group content is 11.9% by weight, the solubility in Swazol 310 is 1000% or more at 20 ° C., and the viscosity after storage at 50 ° C. for 1 month is 1300 mPa · s, The NCO group content was 11.5% by weight, and an increase in viscosity and a decrease in NCO group content were observed.

[0046]

The polyisocyanate composition of the present invention is
Since it has excellent long-term storage stability and a high solid content can be achieved, it is possible to suppress the amount of organic solvent released into the atmosphere. Also, since it is diluted with a low polar organic solvent,
Not only can the working environment be improved, but overcoating can be performed without damaging the underlying coating film during repair work. Furthermore, the polyisocyanate composition of the present invention is excellent in compatibility and reactivity with various polyols such as acrylic polyol, polyester polyol, epoxy polyol, alkyd polyol, and fluorine polyol, and therefore, paints, adhesives, inks, coating materials, Casting material,
It can be used as a curing agent for elastomers and foams, and as a raw material for plastic materials.

Claims (1)

[Claims] 1. Hexamethylene diisocyanate, or an aliphatic diisocyanate composed of a mixture of hexamethylene diisocyanate and isophorone diisocyanate, and an aliphatic primary monoalcohol having 6 to 9 carbon atoms are urethanized, and then the isocyanurate-forming catalyst is used. The viscosity at 25 ° C. obtained by reacting in the presence of the solvent and the aliphatic diisocyanate is 5
A polyisocyanate composition comprising a polyisocyanate mixture of a polyisocyanate having an isocyanurate structure and a polyisocyanate having an allophanate structure at 0 to 1,400 mPa · s and a low polar organic solvent.