JP2015052041A - Allophanatizing and isocyanurating catalyst, method for producing the catalyst, polyisocyanate composition using the catalyst, method for producing the composition, and stretchable paint composition using the composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a catalyst which exhibits stable reactivity without being affected by a protonic acid generated from hydrolyzable chlorine and a method for producing the same, and to provide a polyisocyanate composition which is soluble in a low polar solvent and is excellent in stretchability, and a stretchable paint hardener using the same.SOLUTION: An allophanatizing and isocyanurating catalyst having a specific structural unit can be obtained by subjecting a specific metal carboxylate to an oxidation treatment, the catalyst being free from an effect of a protic acid generated from hydrolyzable chlorine and does not cause reaction inhibition. Further, when this catalyst is used, there are obtained: a polyisocyanate composition having excellent solubility in a low polar solvent and excellent stretchability; and a stretchable paint hardener.

Description

The present invention relates to an allophanate isocyanurate-forming catalyst, a method for producing the catalyst, a polyisocyanate composition using the catalyst, a method for producing the composition, and an extensible coating composition using the composition.

Two-component curable urethane coatings that use polyisocyanate as a component provide coatings with excellent weather resistance and abrasion resistance. Conventionally, coating of outdoor substrates such as buildings and civil engineering structures, It is used for repair and plastic coating.
Due to the high polarity of polyisocyanate, these paints generally contain strong solvents such as aromatic hydrocarbon solvents such as toluene and xylene, and ester solvents such as butyl acetate, that is, solvents with strong dissolving power. It was used.

Since these strong solvents have a strong odor, they tend to be avoided in recent years in terms of improving the working environment and reducing the burden on the global environment. In addition, when repairing or repainting by repainting from the top of the old paint film, if the solvent for repair contains a strong solvent with high dissolving power, the old paint film will swell or dissolve, and the old paint There was a need to repair even the paint film. As a result, problems such as enlargement and complication of painting work, increase in painting cost, and extension of the construction period may occur.
In addition, when used in coatings for building exteriors or coatings for heavy anticorrosion, there have been problems such as cracks in building outer walls, concrete cracks, or failure to follow metal elongation, and cracking of the coating film.

Against this background, in recent years, development of polyisocyanates that are easily soluble in low-polar organic solvents and can impart extensibility has been underway. As a polyisocyanate excellent in dilutability in a low polar organic solvent, a polyisocyanate compound obtained by reacting an aliphatic diisocyanate and a polyol having a dilutability in a low polar organic solvent of 100% or more has been proposed. The polyisocyanate compound thus obtained is excellent in extensibility of the coating film and dissolution in an aliphatic, alicyclic and / or aromatic hydrocarbon organic solvent having an aniline point in the range of 10 to 70 ° C. (For example, refer to Patent Document 1).

Further, as a polyisocyanate having excellent solubility in a low-polar organic solvent and compatibility with a silicate compound, a predetermined allophanate from an aliphatic diisocyanate and / or an alicyclic diisocyanate and a monoalcohol having 1 to 20 carbon atoms. Polyisocyanate compounds having a molar ratio of groups / isocyanurate groups and a specific molecular weight range have been proposed. The polyisocyanate compound thus obtained is excellent in extensibility of the coating film and dissolution in an aliphatic, alicyclic and / or aromatic hydrocarbon organic solvent having an aniline point in the range of 10 to 70 ° C. (For example, see Patent Document 2).

Furthermore, by using tin octylate as an aliphatic diisocyanate, a monoalcohol having 11 or more carbon atoms and a catalyst as a polyisocyanate having improved solubility in a low-polar organic solvent such that the aniline point exceeds 70 ° C., A polyisocyanate compound in which an allophanate group and an isocyanurate group are simultaneously generated has been proposed (see, for example, Patent Document 3).

JP-A-8-198928 JP 2008-24828 A JP 2010-150455 A

However, conventional polyisocyanate compounds and extensible paint curing agents have low storage stability at low temperatures, and insufficient solubility in low-polarity organic solvents with low solvency, There was a risk of problems such as poor appearance and low weather resistance.

In the reaction for obtaining the polyisocyanate compound, hydrolyzable chlorine contained in the organic diisocyanate raw material may react with the catalyst to produce a protonic acid, thereby causing reaction inhibition. This reaction inhibition is particularly remarkable for the isocyanurate-forming reaction. When trying to obtain a polyisocyanate compound containing allophanate groups and isocyanurate groups, most of the products obtained are allophanate group-containing polyisocyanate compounds. It was very difficult to obtain the object. Further, even when a polyisocyanate compound containing both linking groups is obtained, it is a mixture of an allophanate group-containing polyisocyanate compound and an isocyanurate group-containing polyisocyanate compound. Problems such as a decrease in solubility in polar organic solvents, a decrease in storage stability accompanying the addition of a catalyst, and a decrease in extensibility have been made permanent.

Here, hydrolyzable chlorine means that when an organic diisocyanate is obtained by reaction of an amine compound and phosgene, it is contained in an organic diisocyanate raw material in an amount of about 0.001 to 1% by mass as an impurity, and hydrochloric acid is generated by hydrolysis. It is a general term for substances to be used. The main hydrolyzable chlorine is a hydrochloride of a carbamoyl chloride compound in which hydrochloric acid is added to an isocyanate group.

The present invention has been made on the basis of the above circumstances, and even when an organic diisocyanate having a high concentration of hydrolyzable chlorine is used, it is not affected by the protonic acid from hydrolyzable chlorine, and is stable allophanate. Provided are a catalyst exhibiting reactivity of the reaction and isocyanuration reaction, and a method for producing the same. In addition, by using this catalyst, a polyisocyanate composition excellent in storage stability at low temperatures and solubility in a low-polar organic solvent, and a method for producing the same are provided, as well as recoatability, coating film properties, and extension. Another object of the present invention is to provide a curing agent for an extensible paint having excellent properties.

As a result of repeated studies, the present inventors have used organic diisocyanates with high hydrolyzable chlorine concentration as raw materials by using a compound of a carboxylic acid metal salt having a specific structural unit as an allophanate isocyanurate catalyst. Even in this case, the polyisocyanate composition can be obtained without inhibiting the allophanate reaction and the isocyanurate reaction. Moreover, it discovered that the hardening | curing agent for extensible paints obtained by making this polyisocyanate composition and elastic polyol react was excellent in extensibility, and resulted in this invention.

（一般式（１）のＭは、錫、ジルコニウム、亜鉛より選ばれる四価の金属を示す。Ｒは、炭素数が１〜２０のアルキル基、シクロアルキル基、フェニル基より選ばれる結合基を示す。）
（２）前記（１）のアロファネート・イソシアヌレート化触媒（Ａ）が、下記の一般式（２）で示される化合物である。

（一般式（２）のＭは、錫、ジルコニウム、亜鉛より選ばれる四価の金属を示す。Ｒは、炭素数が１〜２０のアルキル基、シクロアルキル基、フェニル基より選ばれる結合基を示す。重合度ｎは、２〜１００の整数を示す。）
（３）前記（１）のアロファネート・イソシアヌレート化触媒（Ａ）が、下記の一般式（３）で示される化合物である。

（一般式（３）のＭは、錫、ジルコニウム、亜鉛より選ばれる四価の金属を示す。Ｒは、炭素数が１〜２０のアルキル基、シクロアルキル基、フェニル基より選ばれる結合基を示す。重合度ｎは、２〜１００の整数を示す。）
（４）前記（１）〜（３）に記載のアロファネート・イソシアヌレート化触媒（Ａ）における四価の金属含有量が、全金属含有量に対して、少なくとも１０質量％であることを特徴とする。
（５）前記（１）〜（４）に記載のアロファネート・イソシアヌレート化触媒の製造方法が、少なくとも一種類の一般式（４）〜一般式（６）で示されるカルボン酸金属塩を酸化反応することによりアロファネート・イソシアヌレート化触媒（Ａ）を得ることを特徴とする。

（一般式（４）〜一般式（６）のＭは、錫、ジルコニウム、亜鉛より選ばれる二価の金属を示す。Ｒは、炭素数が１〜２０のアルキル基、シクロアルキル基、フェニル基より選ばれる結合基を示す。）
（６）ポリイソシアネート組成物が、前記（１）〜（５）に記載のアロファネート・イソシアヌレート化触媒（Ａ）の存在下で、有機ジイソシアネート（Ｂ）と、モノアルコール（Ｃ）との反応から得られ、有機ジイソシアネート（Ｂ）が、脂肪族ジイソシアネート、又は脂環族ジイソシアネートであり、モノアルコール（Ｃ）が、炭素数１〜２０のアルキル基を含有し、ポリイソシアネート組成物中のアロファネート基とイソシアヌレート基が、モル比でアロファネート基／イソシアヌレート基＝８０／２０〜３０／７０含有することを特徴とする。
（７）ポリイソシアネート組成物の製造方法が、
第１工程：有機ジイソシアネート（Ｂ）と、モノアルコール（Ｃ）をウレタン化反応させてイソシアネート基末端プレポリマーＩを製造する工程、
第２工程：イソシアネート基末端プレポリマーＩと、アロファネート・イソシアヌレート化触媒（Ａ）とを用いて、アロファネート化反応とイソシアヌレート化反応によりイソシアネート基末端プレポリマーＩＩを製造する工程、
第３工程：イソシアネート基末端プレポリマーＩＩを反応停止剤により反応停止を行う工程、
第４工程：薄膜蒸留又は溶剤抽出によって、遊離の有機ジイソシアネート（Ｂ）の含有量を１質量％未満になるまで除去する工程、
により、前記（６）に記載したポリイソシアネート組成物を得ることを特徴とする。
（８）伸展性塗料用硬化剤が、前記（６）、又は（７）に記載のポリイソシアネート組成物と、ポリオール（Ｄ）を反応させて得ることを特徴とする。
（９）前記（８）の伸展性塗料用硬化剤が、ＪＩＳ Ｋ ２２５６に準じたアニリン点、又は混合アニリン点が５〜１００℃の有機溶剤（Ｅ）とを含むことを特徴とする。 That is, the outline | summary of this invention is shown by the following (1)-(9).
(1) The allophanate isocyanurate-forming catalyst (A) contains a structural unit represented by the following general formula (1).

(M in the general formula (1) represents a tetravalent metal selected from tin, zirconium and zinc. R represents a bonding group selected from an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group and a phenyl group. Show.)
(2) The allophanate-isocyanurate catalyst (A) of (1) is a compound represented by the following general formula (2).

(M in the general formula (2) represents a tetravalent metal selected from tin, zirconium, and zinc. R represents a bonding group selected from an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group, and a phenyl group. The polymerization degree n is an integer of 2 to 100.)
(3) The allophanate-isocyanurate catalyst (A) of (1) is a compound represented by the following general formula (3).

(M in the general formula (3) represents a tetravalent metal selected from tin, zirconium and zinc. R represents a bonding group selected from an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group and a phenyl group. The polymerization degree n is an integer of 2 to 100.)
(4) The tetravalent metal content in the allophanate isocyanurate catalyst (A) according to (1) to (3) is at least 10% by mass with respect to the total metal content. To do.
(5) The method for producing an allophanate / isocyanurate catalyst according to (1) to (4) above oxidizes at least one kind of carboxylic acid metal salt represented by the general formula (4) to the general formula (6). By doing so, an allophanate isocyanurate-forming catalyst (A) is obtained.

(M in the general formulas (4) to (6) represents a divalent metal selected from tin, zirconium, and zinc. R represents an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group, and a phenyl group. A linking group selected from the above.
(6) The polyisocyanate composition is obtained by reacting the organic diisocyanate (B) with the monoalcohol (C) in the presence of the allophanate / isocyanurate-forming catalyst (A) described in (1) to (5) above. The obtained organic diisocyanate (B) is an aliphatic diisocyanate or an alicyclic diisocyanate, the monoalcohol (C) contains an alkyl group having 1 to 20 carbon atoms, and an allophanate group in the polyisocyanate composition. The isocyanurate group is characterized by containing allophanate group / isocyanurate group = 80/20 to 30/70 in molar ratio.
(7) A method for producing a polyisocyanate composition comprises:
First step: A step of producing an isocyanate group-terminated prepolymer I by subjecting an organic diisocyanate (B) and a monoalcohol (C) to a urethanization reaction,
Second step: Using the isocyanate group-terminated prepolymer I and the allophanate / isocyanurate catalyst (A) to produce an isocyanate group-terminated prepolymer II by an allophanate reaction and an isocyanurate reaction,
Third step: a step of stopping the reaction of the isocyanate group-terminated prepolymer II with a reaction stopper,
Fourth step: a step of removing the content of free organic diisocyanate (B) by thin film distillation or solvent extraction until the content is less than 1% by mass;
To obtain the polyisocyanate composition described in (6) above.
(8) A hardener for extensible paint is obtained by reacting the polyisocyanate composition according to (6) or (7) above with a polyol (D).
(9) The curing agent for extensible paint according to (8) above includes an organic solvent (E) having an aniline point according to JIS K 2256 or a mixed aniline point of 5 to 100 ° C.

According to the allophanate / isocyanurate conversion catalyst of the present invention and the method for producing the catalyst, even if a polyisocyanate having a high hydrolyzable chlorine concentration is used by subjecting a specific carboxylic acid metal salt to an oxidation treatment, hydrolysis can be performed. An allophanate isocyanuration catalyst containing a specific structural unit which is not affected by protonic acid generated from basic chlorine and does not cause reaction inhibition is obtained. In addition, the polyisocyanate composition containing allophanate groups and isocyanurate groups obtained by using this catalyst is excellent in solubility in a low-polar organic solvent, and is an extensible paint obtained by reacting this with an elastic polyol. The curing agent for coating can be a curing agent for a coating film having excellent extensibility and recoatability.

The allophanate / isocyanurate-forming catalyst (A) of the present invention contains a tetravalent metal in the structural unit represented by the general formula (1), thereby suppressing decomposition of hydrolyzable chlorine and causing reaction inhibition. Reduces the production of protonic acids. Further, it is a catalyst that does not inhibit the reaction even when the concentration of the protonic acid generated from the decomposition of hydrolyzable chlorine is high, and is capable of allophanate and isocyanurate.

In addition, the allophanate / isocyanurate catalyst (A) is preferable because the compound specified by the general formula (2) or the general formula (3) can efficiently proceed to the allophanate reaction and the isocyanurate reaction.

The allophanate / isocyanuration catalyst (A) is a carboxylic acid metal salt represented by the general formula (1) to the general formula (3), and M is at least one kind selected from tin, zirconium, and zinc. Is a valent metal. In the case of other metals, either the allophanate reaction or the isocyanurate reaction proceeds selectively to produce allophanate groups and isocyanurate groups at the same time, or allophanate groups are produced, and isocyanurate groups are immediately produced. It is difficult to obtain a polyisocyanate composition containing both linking groups in one molecule. For this reason, the obtained polyisocyanate composition has a possibility that the extensibility fall and the solubility to a low polar organic solvent may fall.

The side chain R is a linking group selected from an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group, and a phenyl group. In the case of other side chains, there is a possibility that precipitates may be formed due to a decrease in solubility of the catalyst in a low-polar solvent or a polyisocyanate composition, or due to aging.
Specific examples of carboxylic acids include acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, heptylic acid, octylic acid, pelargonic acid, capric acid, lauric acid, myristic acid, palmitic acid, margaric acid, stearic acid, Saturated aliphatic carboxylic acids such as velcrostearic acid, aragdic acid, 2-ethylhexanoic acid, saturated monocyclic carboxylic acids such as cyclopropyl carboxylic acid, cyclobutyl carboxylic acid, cyclopentyl carboxylic acid, cyclohexyl carboxylic acid, bicyclo (4.4 0.0) saturated polycyclic carboxylic acids such as decane-2-carboxylic acid, unsaturated fatty carboxylic acids such as palmitoleic acid, oleic acid, linoleic acid, linolenic acid, vaccenic acid, eleostearic acid, arachidonic acid, diphenylacetic acid Aromatic aliphatic carboxylic acids such as benzoic acid and toluic acid Bonn acid and the like.
The allophanate isocyanurate-forming catalyst (A) can be used alone or in combination of two or more.

Moreover, the polymerization degree of the allophanate isocyanurate-forming catalyst (A) represented by the general formula (2) or the general formula (3) is an integer of 2 to 100. When the degree of polymerization exceeds the upper limit, the solubility may be lowered in a low polarity organic solvent.

The tetravalent metal content of the allophanate / isocyanurate conversion catalyst (A) is calculated based on the iodine solution titration method, and is preferably at least 10% by mass based on the total metal content. In addition to this, the method for measuring the metal content may be determined by M-O- by quantitative determination based on weight change (calculated from an increase amount due to oxidation, assuming that the atomic weight of oxygen is 16) and infrared spectroscopy (IR analysis). It is also possible to perform quantification from the relative absorbance ratio of the binding spectrum of M (when M is tin: 603 cm ⁻¹ ). Furthermore, the quantification of the total metal content can also be measured using inductively coupled plasma emission spectroscopy (ICP analysis).
When the tetravalent metal content of the allophanate / isocyanurate-forming catalyst (A) is less than the lower limit, hydrolyzable chlorine is decomposed to produce protonic acid, thereby causing reaction inhibition and the desired product. May not be obtained.

Here, as a measuring method of the iodine solution titration method, the tetravalent metal content can be calculated by obtaining the total metal content and the divalent metal content by the following operation.
<Measurement method of total metal content: A (mass%)>
(1) About 0.5 g of a sample is weighed into a 500 ml Erlenmeyer flask, and 100 ml of hydrochloric acid, 5 g of sodium phosphinate, and 1 ml of a saturated mercuric chloride solution are added.
(2) A Geckel valve is attached to the Erlenmeyer flask, sodium hydrogen carbonate and pure water are added, the air is shut off, heated on a hot plate for 40 minutes, and then cooled to 20 ° C. or lower.
(3) Add 2 ml of starch solution, titrate with 0.05 mol / l iodine solution, and calculate the total metal content from the titration with the end point when the iodine starch reaction is colored black purple.
<Measurement method of divalent metal content: B (mass%)>
(1) Add a small piece of marble, 2 g of sodium bicarbonate, and 20 ml of pure water to a 300 ml Erlenmeyer flask.
(2) Add 30 ml of hydrochloric acid to this, and add about 0.5 g of a pre-weighed sample.
(3) Titrate with 0.05 mol / l iodine solution, and when the end point is near, add 2 ml of starch solution, and when the end point is colored black-purple of iodine starch reaction, the end point is the divalent metal content from titration Is calculated.
<Calculation of tetravalent metal content: C (mass%)>
C = (A−B) / A × 100
(1) A: Total metal content (% by mass)
(2) B: Divalent metal content (mass%)
(3) C: Tetravalent metal content (% by mass)

Moreover, as a measuring method of content of General formula (1)-General formula (3), it can calculate based on a nuclear magnetic resonance spectrum (NMR). The NMR measurement conditions when the metal is tin are as follows.

<NMR: measurement of content of structural unit>
(1) Measuring apparatus: ECX400M (manufactured by JEOL Ltd., 119Sn-NMR)
(2) Measurement temperature: 23 ° C
(3) Sample concentration: 0.1 g / 1 ml
(4) Integration count: 64
(5) Relaxation time: 5 seconds (6) Solvent: Deuterated chloroform (7) Evaluation method: Signal of tetravalent tin atom bonded to structural unit around 954 ppm and signal of divalent tin atom around 703 ppm Measure the content of bonding groups from the area ratio.

The production method of the allophanate-isocyanurate-forming catalyst of the present invention includes monodentate coordination, bidentate coordination, and monodentate and bidentate complex bonds represented by formulas (4) to (6). It is obtained by subjecting at least one carboxylic acid metal salt in a state to an oxidation reaction.

(M in the general formulas (4) to (6) represents a divalent metal selected from tin, zirconium, and zinc. R represents an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group, and a phenyl group. A linking group selected from the above.

As a method for oxidizing the carboxylic acid metal salt, a known oxidant can be used, but safety, moderate oxidation ability, purification is unnecessary, and synthesis is possible with a simple apparatus. A method in which oxygen is used and the metal carboxylate is heated in an oxygen stream or an oxidation treatment method using ozone is preferred.

The concentration of oxygen in the oxidation treatment method using oxygen is preferably in the range of 20 to 100% by mass. If it is less than the lower limit, the oxidation reaction does not proceed sufficiently, and the tetravalent metal content may be reduced.

Moreover, it is preferable that it is the range of 5-120 degreeC as reaction temperature of the oxidation treatment method by oxygen. If the amount is less than the lower limit, the oxidation reaction does not proceed sufficiently and the tetravalent metal content may be reduced. If the upper limit is exceeded, the produced allophanate-isocyanurate catalyst (A) is decomposed or There is a risk of coloring.

As an oxidation treatment method using ozone, a commercially available ozone generator can be used, and the ozone concentration and reaction temperature can be appropriately adjusted so that the allophanate-isocyanurate catalyst (A) is not decomposed.

In addition, when the carboxylic acid metal salt is a solid, it is possible to carry out the oxidation reaction as it is, but it is preliminarily dissolved in a soluble solvent for the carboxylic acid metal salt because of the uniformity of the reaction and the reaction time. It is preferable to perform an oxidation reaction.

The reaction time of the oxidation reaction varies depending on the concentration of the carboxylic acid metal salt, the oxygen concentration and the ozone concentration, the reaction temperature, and the type of the carboxylic acid metal salt, but is generally 2 to 72 hours. In the reaction, there is no problem if the reaction is carried out by an intermittent reaction in addition to the continuous reaction.

The allophanate / isocyanuration catalyst (A) thus produced may simultaneously produce the compound of the general formula (7), but is contained within a range that does not affect the allophanate reaction and the isocyanurate reaction. Is not a problem.

(M in the general formula (7) represents a tetravalent metal selected from tin, zirconium and zinc. R represents a linking group selected from an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group and a phenyl group. Show.)

The allophanate / isocyanurate conversion catalyst (A) of the present invention is suitable as a catalyst for producing a polyisocyanate composition containing both allophanate and isocyanurate groups in one molecule. Since it contains in an inside, compared with the conventional mixture of an allophanate group containing polyisocyanate compound and an isocyanurate group containing polyisocyanate compound, an improvement in a weather resistance and the solubility with respect to a low polar organic solvent can be improved.

A polyisocyanate composition containing both allophanate group and isocyanurate group bonding group in one molecule comprises an organic diisocyanate (B), a monoalcohol (C), and an allophanate isocyanurate-forming catalyst (A). The polyisocyanate composition containing both bonding groups in one molecule can be obtained by simultaneously generating allophanate groups and isocyanurate groups by the above reaction, or generating allophanate groups and immediately generating isocyanurate groups. .

Here, examples of the organic diisocyanate (B) used include aliphatic diisocyanates and / or alicyclic diisocyanates from the viewpoint of weather resistance and the like. In addition, aromatic diisocyanates and araliphatic diisocyanates can be used in combination as long as performance does not deteriorate.

<Aliphatic diisocyanate>
Specific examples of the aliphatic isocyanate include hexamethylene diisocyanate, tetramethylene diisocyanate, 2-methyl-pentane-1,5-diisocyanate, 3-methyl-pentane-1,5-diisocyanate, lysine diisocyanate, and trioxyethylene diisocyanate. Can be mentioned.

<Alicyclic diisocyanate>
Specific examples of the alicyclic diisocyanate include isophorone diisocyanate, cyclohexyl diisocyanate, hydrogenated diphenylmethane diisocyanate, norbornane diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated xylene diisocyanate, hydrogenated tetramethylxylene diisocyanate and the like.

<(C) Monoalcohol>
Although it does not specifically limit as monoalcohol (C) used for a polyisocyanate composition, It is preferable that carbon number of an alkyl group is 1-20 from a soluble viewpoint with respect to a low polar organic solvent. . More preferably, it has 3 to 13 carbon atoms.
Specific examples of such monoalcohol (C) include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutanol, 1-pentanol, 2-pentanol, isoamyl alcohol, 1-hexanol, 2-hexanol, 1-heptanol, 1-octanol, 2-ethyl-1-hexanol, 3,3,5-trimethyl-1-hexanol, tridecanol, pentadecanol, palmityl alcohol, stearyl alcohol, cyclo Examples include pentanol, cyclohexanol, methylcyclohexanol, trimethylcyclohexanol, and the like, and these can be used alone or in combination of two or more.
Among these monoalcohols, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutanol, 1-pentanol, 2-pentanol, isoamyl alcohol, 1-hexanol, 2-hexanol, 1-heptanol 1-octanol, 2-ethyl-1-hexanol, 3,3,5-trimethyl-1-hexanol, and tridecanol are particularly excellent in solubility in low-polar organic solvents, and can be suitably used.

Next, the specific manufacturing method of a polyisocyanate composition is demonstrated.
As a manufacturing method of a polyisocyanate composition, it manufactures through the 1st process-the 4th process as represented below.
In the first step, an organic diisocyanate (B) and a monoalcohol (C) are charged in an excess amount with respect to the hydroxyl group, and in the presence or absence of an organic solvent at 20 to 120 ° C. Isocyanate group-terminated prepolymer I is produced by urethanization reaction. Here, as a standard of the urethanization reaction, the presence or absence of completion is judged from the isocyanate group content by the neutralization titration method and the relative absorbance ratio of IR analysis.
In the second step, an allophanate / isocyanurate-forming catalyst (A) is added to the isocyanate group-terminated prepolymer I, and the urethane group is substantially absent by IR analysis until the target isocyanate group content is reached. The isocyanate group-terminated prepolymer II is produced by carrying out an isocyanurate reaction and an isocyanurate reaction at 150 ° C. at the same time or immediately after the allophanate reaction.
In the third step, the reaction is stopped by adding a reaction terminator to the isocyanate group-terminated prepolymer II.
In these first to third steps, the reaction is allowed to proceed under nitrogen gas or a dry air stream.
In the fourth step, the isocyanate group-terminated prepolymer II is removed by thin film distillation or solvent extraction until the content of free organic diisocyanate (B) is less than 1% by mass.

Here, the “amount of isocyanate groups in excess” in the first step means that the molar ratio of the isocyanate groups of the organic diisocyanate (B) and the hydroxyl groups of the monool (C) is R = It is preferable to charge so that it may become 6-40 by an isocyanate group / hydroxyl group, More preferably, it is preferable to charge so that it may become R = 7-30. When the amount is less than the lower limit, the amount of the polyisocyanate composition having a higher molecular weight than that of the target product is increased, which may increase the viscosity or decrease the solubility in the low polarity organic solvent. If the upper limit is exceeded, the amount of isocyanate group-terminated prepolymer I that is a precursor of the polyisocyanate composition is reduced, which may lead to a decrease in productivity and yield.

Moreover, the reaction temperature of a urethanation reaction is 20-120 degreeC, Preferably it is 50-100 degreeC. In the urethanization reaction, a known urethanization catalyst can be used. Specifically, organic metal compounds such as dibutyltin diacetate, dibutyltin dilaurate and dioctyltin dilaurate, organic amines such as triethylenediamine and triethylamine, and salts thereof are selected and used. These catalysts can be used alone or in combination of two or more.

The reaction time of the urethanization reaction varies depending on the presence or absence of the catalyst, the type, and the temperature, but is generally within 10 hours, preferably 1 to 5 hours is sufficient.

The amount of the allophanate / isocyanurate-forming catalyst (A) used in the second step is preferably 0.001 to 1.0% by mass relative to the total mass of the organic diisocyanate (B) and the monoalcohol (C). 0.005-0.1 mass% is more preferable.
If it is less than the lower limit, the allophanate reaction and isocyanurate reaction do not proceed sufficiently, and the amount of urethane group-containing polyisocyanate that is a precursor of the polyisocyanate composition increases, resulting in a decrease in the number of average functional groups. There is a risk that the physical properties of the coating film will be lowered, and the productivity and yield will be reduced. When the upper limit is exceeded, the amount of polyisocyanate composition having a molecular weight higher than that of the target product is increased, leading to an increase in viscosity, a decrease in solubility in low-polar organic solvents, and a decrease in reactivity control. There is a fear.

The reaction is carried out at an allophanate reaction and isocyanurate reaction at a temperature of 70 to 150 ° C, preferably 90 to 130 ° C.

Thus, the molar ratio of the allophanate group and isocyanurate group contained in the polyisocyanate composition obtained is 80/20 to 30/70 of the allophanate group / isocyanurate group by appropriately adjusting the reaction time. Adjusted to range. When the molar ratio of isocyanurate groups is less than the lower limit, the physical properties of the hardener for extensible paint obtained by reaction with polyol may be reduced. Moreover, when exceeding an upper limit, there exists a possibility of causing the fall of the solubility with respect to a low polar organic solvent, and the fall of adhesiveness.

Moreover, in manufacture of a polyisocyanate composition, the method of reacting without including an organic solvent etc., and the method of reacting in presence of an organic solvent are suitably selected.
When the reaction is performed in the presence of an organic solvent, an organic solvent that does not affect the reaction can be used. Specific examples of the organic solvent include aliphatic hydrocarbons such as octane, alicyclic hydrocarbons such as cyclohexane and methylcyclohexane, ketones such as methyl isobutyl ketone and cyclohexanone, esters such as butyl acetate and isobutyl acetate, Ethylene glycol ethyl ether acetate, propylene glycol monomethyl ether acetate, 3-methyl-3-methoxybutyl acetate, glycol ether esters such as ethyl-3-ethoxypropionate, ethers such as dioxane, methylene iodide, monochlorobenzene, etc. And polar aprotic solvents such as N-methylpyrrolidone, dimethylformamide, dimethylacetamide, dimethylsulfoxide, hexamethylphosphonilamide, and the like. These solvents can be used alone or in combination of two or more.
The organic solvent used in the reaction is removed simultaneously with the removal of free organic diisocyanate in the fourth step.

The reaction terminator in the third step has a function of deactivating the activity of the catalyst. Specifically, the organic compound has an inorganic acid such as phosphoric acid and hydrochloric acid, a sulfonic acid group, a sulfamic acid group, and the like. Known compounds such as acids and their esters and acyl halides are used. These reaction terminators can be used alone or in combination of two or more. In addition, the addition time is preferably a rapid addition after completion of the reaction.

The amount of the reaction terminator added varies depending on the kind of the reaction terminator and the catalyst, but is preferably 0.5 to 10 equivalents, and particularly preferably 0.8 to 5.0 equivalents of the catalyst. When there are few reaction terminators, the storage stability of the obtained polyisocyanate composition tends to decrease, and when it is too much, the polyisocyanate composition may be colored.

In the purification step of the fourth step, the residual unreacted organic diisocyanate (B) present in the reaction mixture is subjected to, for example, thin film distillation at 120 to 140 ° C. under a high vacuum of 10 to 100 Pa. The method of removing to 1.0 mass% or less and the method of extracting with an organic solvent are taken. In addition, when the residual content rate of organic diisocyanate (B) exceeds an upper limit, there exists a possibility of causing the fall of an odor and storage stability.

The polyisocyanate composition thus obtained has an average number of functional groups in the range of 2.0 to 5.0 based on the number average molecular weight determined based on gel permeation chromatography (GPC) analysis. If it is less than the lower limit, the crosslinking density may decrease, and the solvent resistance and physical properties of the coating film may decrease. Moreover, when exceeding an upper limit, there exists a possibility of causing the fall of the solubility with respect to a low polar organic solvent, and the fall of adhesiveness.

Moreover, the number average molecular weight of a polyisocyanate composition is 500-3000, Preferably it is 500-2500, More preferably, it is 500-2000. If it is less than the lower limit, the adhesiveness and extensibility may be lowered, and if the upper limit is exceeded, the solubility in low-polar organic solvents and the adhesiveness may be lowered.

Further, the viscosity of the polyisocyanate composition is not particularly limited, but is preferably 2000 mPa · s or less, more preferably 1500 mPa · s or less at 25 ° C., and 1000 mPa · s or less. Is more preferable. When the upper limit is exceeded, the viscosity may be high and difficult to handle during modification with a polyol.

Moreover, the polyisocyanate composition obtained by a series of reaction can obtain the hardening | curing agent for an extensible paint with which extensibility was provided by reaction with a polyol (D).

It is preferable that the number average molecular weight of a polyol (D) exists in the range of 500-20000. If it is less than the lower limit, the extensibility may be lowered, and if it exceeds the upper limit, the solubility in low-polar organic solvents and the adhesion may be lowered.

Here, as a polyol (D) used for the hardening | curing agent for extensible paints of this invention, it is the elastic polyol which used individually or in combination of 2 or more types chosen from polyether polyol, polyester polyol, and polyolefin-type polyol. It is preferable. In addition, polycarbonate polyol, acrylic polyol, silicone polyol, castor oil-based polyol, and fluorine-based polyol can be used in combination as long as the solubility and extensibility in a low-polar organic solvent do not decrease.

<Polyether polyol>
The polyether polyol is a polyether polyol having at least one oxyalkylene group selected from oxyethylene group, oxypropylene group, oxytetramethylene group, and oxycyclohexyl group in the molecular skeleton. Further, an oxypropylene group and / or oxytetramethylene group having a side chain is preferable, and when the content is 60 mol% or more, more preferably 70 mol% or more, and most preferably 80 mol% or more, a low polarity organic The solubility in a solvent is further improved. Among the oxyalkylene groups, the oxypropylene group is particularly excellent in solubility in a low-polar organic solvent, and the oxytetramethylene group is excellent in weather resistance.
Specific examples of such polyether polyols include polyethylene glycol, polypropylene glycol, polypropylene glycol obtained by addition polymerization of ethylene oxide at the end of polypropylene glycol, polyoxypropylene polyoxyethylene copolymer diol, polyoxypropylene polyoxyethylene block polymer Examples thereof include diol and polytetramethylene glycol. In particular, polypropylene glycol and polypropylene glycol obtained by addition polymerization of ethylene oxide at the end of polypropylene glycol are preferable because of their excellent solubility in low-polar organic solvents.

 Polyether polyol production methods include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,5 -Pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 3-methyl-1,5-pentanediol, 3,3-dimethylolheptane, diethylene glycol, dipropylene glycol, Neopentyl glycol, cyclohexane-1,4-diol, cyclohexane-1,4-dimethanol, dimer acid diol, bisphenol A, bis (β-hydroxyethyl) benzene, xylylene glycol, glycerin, trimethylolpropane, pentaerythritol, etc. Low molecular weight poly Initiators or compounds having 2 or more, preferably 2 to 3 active hydrogen groups such as ethylenediamine, propylenediamine, toluenediamine, metaphenylenediamine, diphenylmethanediamine, xylylenediamine and other polyamines And hydroxides such as lithium, sodium and potassium, alcoholates, alkylamines and other strongly basic catalysts, metal porphyrins, complex metal cyanide complexes, complexes of metals with chelating agents of tridentate or higher, hexacyano It can be obtained by addition polymerization of alkylene oxides such as ethylene oxide, propylene oxide, butylene oxide and the like using a complex metal complex such as zinc cobaltate complex as a catalyst. It can also be obtained by ring-opening polymerization of alkyl glycidyl ethers such as methyl glycidyl ether, aryl glycidyl ethers such as phenyl glycidyl ether, and cyclic ether monomers such as tetrahydrofuran.

<Polyester polyol>
The polyester polyol is a polyester polyol having a side chain in the molecular skeleton. Having a side chain in the molecular skeleton is preferable because of excellent extensibility and solubility in a low-polar organic solvent.
Specific examples of polyester polyols include phthalic acid, isophthalic acid, terephthalic acid, naphthalenedicarboxylic acid, succinic acid, tartaric acid, oxalic acid, malonic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, glutaconic acid, azelaic acid, Dicarboxylic acids such as sebacic acid, 1,4-cyclohexyl dicarboxylic acid, α-hydromuconic acid, β-hydromuconic acid, α-butyl-α-ethylglutaric acid, α, β-diethylsuccinic acid, maleic acid, fumaric acid, etc. Or one or more of these anhydrides and the like, 1,2-propanediol, 1,2-butanediol, 1,3-butanediol, 3-methyl-1,5-pentanediol, 3,3-dimethylol Molecular weight of 500 such as heptane, diethylene glycol, dipropylene glycol, neopentyl glycol It may be mentioned those obtained from polycondensation reaction of one or more polyols essential to select polyols that contain side chains below. In addition, ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,9 within a range where the performance does not deteriorate. -Nonanediol, cyclohexane-1,4-diol, cyclohexane-1,4-dimethanol, dimer acid diol, bisphenol A ethylene oxide and propylene oxide adducts, bis (β-hydroxyethyl) benzene, xylylene glycol, glycerin Polyols having a molecular weight of 500 or less such as trimethylolpropane and pentaerythritol can also be used.

<Polyolefin polyol>
As polyolefin polyol, hydrogenation is added to a hydroxyl-terminated prepolymer obtained by polymerizing a compound having two double bonds in the molecule, such as butadiene and isoprene, to make the remaining double bonds saturated aliphatic. It is a compound.

<Polyols that can be used in combination>
In addition, polycarbonate polyol, acrylic polyol, silicone polyol, castor oil-based polyol, and fluorine-based polyol can be used in combination with the elastic polyol as long as the performance does not deteriorate.

<Polycarbonate polyol>
Specific examples of the polycarbonate polyol include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,5- Pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 3-methyl-1,5-pentanediol, 3,3-dimethylolheptane, diethylene glycol, dipropylene glycol, neo Pentyl glycol, diethylene glycol, dipropylene glycol, cyclohexane-1,4-diol, cyclohexane-1,4-dimethanol, dimer acid diol, ethylene oxide and propylene oxide adducts of bisphenol A, bis (β-hydroxyethyl) benze , One or more kinds of low molecular polyols such as xylylene glycol, glycerin, trimethylolpropane and pentaerythritol, dialkyl carbonates such as dimethyl carbonate and diethyl carbonate, alkylene carbonates such as ethylene carbonate and propylene carbonate, diphenyl carbonate, di Examples thereof include those obtained from a dealcoholization reaction or a dephenol reaction with diaryl carbonates such as naphthyl carbonate, dianthryl carbonate, diphenanthryl carbonate, diindanyl carbonate, and tetrahydronaphthyl carbonate.

<Acrylic polyol>
Examples of the acrylic polyol include acrylic acid ester and / or methacrylic acid ester (hereinafter referred to as (meth) acrylic acid ester), acrylic acid hydroxy compound and / or methacrylic acid having at least one hydroxyl group in the molecule that can be a reaction point. Examples thereof include those obtained by copolymerizing an acrylic monomer using a thermal compound, a light energy such as an ultraviolet ray or an electron beam, and the like with a hydroxy compound (hereinafter referred to as a (meth) acrylic acid hydroxy compound) and a polymerization initiator.

<(Meth) acrylic acid ester>
Specific examples of (meth) acrylic acid esters include alkyl esters having 1 to 20 carbon atoms. Specific examples of such (meth) acrylate esters include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, pentyl (meth) acrylate, (Meth) such as hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate Alkyl acrylate, ester of (meth) acrylic acid with cycloaliphatic alcohol such as cyclohexyl (meth) acrylate, phenyl (meth) acrylate, aryl (meth) acrylate such as benzyl (meth) acrylate Can be mentioned. Such (meth) acrylic acid esters can be used singly or in combination of two or more.

<(Meth) acrylic acid hydroxy compound>
Specific examples of the (meth) acrylic acid hydroxy compound have at least one hydroxyl group in the molecule that can be a reaction point with the polyisocyanate composition. Specifically, 2-hydroxyethyl acrylate, 2 -Hydroxypropyl acrylate, 4-hydroxybutyl acrylate, 3-hydroxy-2,2-dimethylpropyl acrylate, and acrylic acid hydroxy compounds such as pentaerythritol triacrylate. Moreover, methacrylic acid hydroxy compounds, such as 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, 3-hydroxy-2,2-dimethylpropyl methacrylate, and pentaerythritol trimethacrylate, are mentioned. These acrylic acid hydroxy compounds and / or methacrylic acid hydroxy compounds can be used singly or in combination of two or more.

<Silicone polyol>
Specific examples of the silicone polyol include a vinyl group-containing silicone compound obtained by polymerizing γ-methacryloxypropyltrimethoxysilane and the like, and α, ω-dihydroxypolydimethylsiloxane having at least one terminal hydroxyl group in the molecule, α, Mention may be made of polysiloxanes such as ω-dihydroxypolydiphenylsiloxane.

<Castor oil-based polyol>
Specific examples of the castor oil-based polyol include linear or branched polyester polyols obtained by a reaction between a castor oil fatty acid and a polyol. Dehydrated castor oil, partially dehydrated castor oil partially dehydrated, and hydrogenated castor oil added with hydrogen can also be used.

<Fluorine-based polyol>
A specific example of the fluorine-based polyol is a linear or branched polyol obtained by a copolymerization reaction using a fluorine-containing monomer and a monomer having a hydroxy group as essential components. Here, the fluorine-containing monomer is preferably a fluoroolefin, for example, tetrafluoroethylene, chlorotrifluoroethylene, trichlorofluoroethylene, hexafluoropropylene, vinylidene fluoride, vinyl fluoride, trifluoromethyl trifluoroethylene. Is mentioned. Examples of the monomer having a hydroxyl group include hydroxyalkyl vinyl ethers such as hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether and cyclohexanediol monovinyl ether, hydroxyalkyl allyl ethers such as 2-hydroxyethyl allyl ether, and hydroxyalkyl vinyl crotonates. Examples thereof include monomers having a hydroxyl group, such as hydroxyl group-containing vinyl carboxylate or allyl ester.

The modification amount of the polyol (D) used in the present invention is preferably 8 to 70% by mass, and preferably 10 to 50% by mass with respect to the polyisocyanate composition. If it is less than the lower limit, the extensibility may be lowered. If the upper limit is exceeded, the solubility in a low-polar organic solvent and the weather resistance may be lowered due to an increase in the urethane bond group.

By adding an organic solvent (E) having an aniline point or a mixed aniline point of 5 to 100 ° C. to the hardener for the extensible paint of the present invention, recoating can be performed without eroding the base layer when overcoating. It becomes a hardener for extensible paints that is excellent in solvent properties, and further excellent in solvent resistance and extensibility.

Here, the organic solvent (E) used as the diluting solvent is an organic solvent having an aniline point or a mixed aniline point in the range of 5 to 100 ° C., and erodes the base layer when the paint is repeatedly applied. In order to obtain good recoatability, the aniline point or mixed aniline point is more preferably in the range of 5 to 90 ° C, and the aniline point or mixed aniline point is more preferably in the range of 5 to 85 ° C. preferable. If it is less than the lower limit, the odor of the organic solvent becomes strong in addition to the decrease in recoatability, and the working environment may be deteriorated.

Here, the “aniline point” is a minimum temperature at which an equal volume of aniline and a sample (organic solvent) exist as a uniform mixed solution. The aniline point or the mixed aniline point can be measured according to the test method described in “Petroleum products—aniline point and mixed aniline point test method” of JIS K 2256.

<Organic solvent (E)>
Specific examples of the organic solvent (E) include Solvesso 100 (manufactured by ExxonMobil, mixed aniline point: 14 ° C.), Solvesso 150 (manufactured by ExxonMobil, mixed aniline point: 18 ° C.), Swazol 100 (Maruzen Petrochemical Co., Ltd.) Manufactured, mixed aniline point: 25 ° C.), swazol 200 (manufactured by Maruzen Petrochemical Co., Ltd., mixed aniline point: 24 ° C.), swazol 1500 (manufactured by Maruzen Petrochemical Co., Ltd., mixed aniline point: 17 ° C.), swazol 1800 (maruzen petrochemical) Manufactured by Co., Ltd., mixed aniline point: 16 ° C.), Swazol 1000 (manufactured by Maruzen Petrochemical Co., Ltd., mixed aniline point: 13 ° C.), Vegasol ARO-80 (manufactured by ExxonMobil, mixed aniline point: 25 ° C.), Vegazole R-100 (ExxonMobil, mixed aniline point: 14 ° C.), Idemitsu Ivzole 150 (Idemitsu Kosan, mixed aniline) Point: 15 ° C.), Idemitsu Ibsol 100 (produced by Idemitsu Kosan Co., Ltd., mixed aniline point: 14 ° C.), methylcyclohexane (aniline point: 40 ° C.), ethylcyclohexane (aniline point: 44 ° C.), mineral spirit (mineral terpene, In addition to aniline point (56 ° C), turpentine oil (aniline point: 20 ° C), HAWS (manufactured by Shell Japan, aniline point: 17 ° C), Essonaphtha No. 6 (manufactured by ExxonMobil, aniline point: 43 ° C), LAWS (manufactured by Shell Japan, aniline point: 44 ° C), pegasol 3040 (manufactured by ExxonMobil, aniline point: 55 ° C), A Solvent (JX Nippon Oil & Gas Energy Company, aniline point: 45 ° C), Clensol (manufactured by JX Nippon Mining & Energy Corporation, aniline point: 64 ° C), Mineral Spirit A (manufactured by JX Nippon Mining & Energy Corporation, aniline point: 43 ° C), Hyalom 2S ( JX Nippon Mining & Energy Corporation, aniline point: 44 ° C., LAWS (manufactured by Shell Chemicals Japan, aniline point: 44 ° C.), Pegasol 3040 (exxon mobile, aniline point: 55 ° C.), A solvent (JX Nikko) Nisseki Energy Co., Ltd., aniline point: 45 ° C), Clensol (JX Nippon Mining & Energy Co., Ltd. : 64 ° C), Mineral Spirit A (manufactured by JX Nippon Mining & Energy Corporation, aniline point: 43 ° C), Hyalom 2S (manufactured by JX Nippon Mining & Energy Corporation, aniline point 4: 4 ° C), Linearlen 10 (manufactured by Idemitsu Kosan Co., Ltd.) , Α-olefinic hydrocarbon, aniline point: 44 ° C., linearene 12 (produced by Idemitsu Kosan Co., Ltd., α-olefinic hydrocarbon, aniline point: 54 ° C.), Exol D30 (manufactured by ExxonMobil, naphthenic solvent, aniline point: 63 ° C), Ricasolve 900 (manufactured by Nippon Nippon Chemical Co., Ltd., hydrogenated C9 solvent, aniline point: 53 ° C), Ricasolve 910B (manufactured by Nippon Nippon Chemical Co., Ltd., hydrogenated C9 solvent, aniline point: 40 ° C), Ricasolve 1000 (new) Nippon Rika Co., Ltd., hydrogenated C9 solvent, aniline point: 55 ° C.), IP solvent 1620 (manufactured by Idemitsu Kosan Co., Ltd., aniline point: 81 ° C.), IP sorbent 1016 (Idemitsu Kosan Co., Ltd., aniline point: 72 ° C.), IP Solvent 2028 (Idemitsu Kosan Co., Ltd., aniline point: 89 ° C.), IP Solvent 2835 (Idemitsu Kosan Co., Ltd., aniline point: 104 ° C.), Shellsol S ( Shell Chemicals Japan, aniline point: 78 ° C), Isopar G (ExxonMobil, aniline point: 78 ° C), Nisseki Isosol 300 (manufactured by JX Nippon Mining & Energy Corporation, aniline point: 80 ° C), normal paraffin SL (manufactured by JX Nippon Oil & Energy Corporation, aniline point: 80 ° C.), Marcazole R (manufactured by Maruzen Petrochemical Co., Ltd., aniline point: 88 ° C.) and the like. These organic solvents (E) can be used individually or in mixture of 2 or more types.

These organic solvents (E) contain an aromatic hydrocarbon solvent, ester solvent, ether solvent, and if the aniline point or mixed aniline point is within the range of 5 to 100 ° C., it is used as a solvent. It is also possible.

In addition, the content of the organic solvent (E) in which the aniline point or the mixed aniline point in the extensible paint curing agent is in the range of 5 to 100 ° C. is particularly limited as long as it does not cause turbidity or precipitation. Although it is not a thing, in this invention, it is preferable to contain in 10-90 mass%.

By making a two-component paint using the thus obtained hardener for extensible paint and a polyol having a hydroxyl value of 5 to 200 mgKOH / g as the main agent, the film is rich and flexible. Can be formed. Here, as the main agent, the polyether polyol, polyester polyol, polyolefin polyol, polycarbonate polyol, acrylic polyol, silicone polyol, castor oil-based polyol, fluorine-based polyol and other polyols mentioned in the above polyol (D) are used. At least one or more polyols can be used. In addition, the proportion of the hardener for the extensible paint and the main agent in the two-component paint is not particularly limited, but the isocyanate group in the hardener for the extensible paint and the hydroxyl group in the main agent are not limited. It is preferable that the molar ratio is 0.5 to 1.5 in terms of R = isocyanate group / hydroxyl group. If it is less than the lower limit, the hydroxyl group becomes excessive, which may cause a decrease in adhesion. Moreover, there exists a possibility that a crosslinking density may fall and the fall of durability and the fall of the extensibility of a coating film may be produced. When the upper limit is exceeded, the isocyanate group becomes excessive and reacts with moisture in the air, which may cause swelling of the coating film and a decrease in adhesion.

In addition, the two-component paint can use a known urethanization catalyst as appropriate in consideration of pot life, curing conditions, working conditions, and the like. Specifically, organic metal compounds such as dibutyltin diacetate, dibutyltin dilaurate and dioctyltin dilaurate, organic amines such as triethylenediamine and triethylamine, and salts thereof are selected and used. These catalysts can be used alone or in combination of two or more.

Here, the curing condition of the two-component paint is not particularly limited because it varies depending on the catalyst or the like, but the curing temperature is −5 to 120 ° C., the humidity is 10 to 95% RH, and the curing time is 0. It is preferably 5 to 168 hours.

If necessary, for example, antioxidants such as 2,6-di-tert-butyl-4-methylphenol, ultraviolet absorbers, pigments, dyes, solvents, flame retardants, hydrolysis inhibitors, lubricants, Additives such as a plasticizer, a filler, an antistatic agent, a dispersant, a catalyst, a storage stabilizer, a surfactant, and a leveling agent can be appropriately blended in the two-component paint.

These two-component paints can be applied to form a film thickness of at least 10 μm on the surface of the adherend by a known method such as spraying, brushing, dipping, or coater.
Here, the adherend is not particularly limited, and is stainless steel, phosphate-treated steel, zinc steel, iron, copper, aluminum, brass, glass, slate, acrylic resin, polycarbonate resin, polyethylene terephthalate resin, polyethylene naphthalate. Phthalate resin, polybutylene phthalate resin, polystyrene resin, AS resin, ABS resin, polycarbonate-ABS resin, 6-nylon resin, 6,6-nylon resin, MXD6 nylon resin, polyvinyl chloride resin, polyvinyl alcohol resin, polyurethane resin, Phenol resin, melamine resin, polyacetal resin, chlorinated polyolefin resin, polyolefin resin, polyamide resin, polyether ether ketone resin, polyphenylene sulfide resin, NBR resin, chloroprene resin, SBR resin, S An adherend formed of a material such as a BS resin, an olefin resin such as polyethylene or polypropylene subjected to corona discharge treatment or other surface treatment, or a coating layer that can be formed on the surface of the adherend was formed. An adherend can be used.

Since the film thickness of the coating film formed on the adherend surface layer is excellent in recoatability and durability, a film thickness of at least 10 μm may be formed on the adherend. When the film thickness is less than 10 μm, the durability is lowered, and there is a possibility that the coating film is torn by impact.

Thus, even when the organic diisocyanate having a high hydrolyzable chlorine concentration is used as a raw material by using the compound of the metal carboxylate having a specific structure as the allophanate / isocyanurate conversion catalyst (A), A polyisocyanate composition containing both bonding groups in one molecule can be obtained without inhibiting the allophanatization reaction and the isocyanuration reaction.
Further, the curing agent for extensible paint obtained by modifying the polyisocyanate composition of the present invention with a polyol is excellent in solubility and extensibility in a low polar organic solvent. It is possible to easily obtain a two-component paint having excellent properties.
As described above, the hardener for extensible paints of the present invention combined with the main agent is used for paints for architectural equipment, paints for heavy anticorrosion, paints for automobiles, paints for home appliances, information equipment such as personal computers and mobile phones. In particular, it is suitably used in architectural exterior paints and heavy anticorrosion paints for repainting applications.

Examples of the present invention will be described below, but the present invention is not limited to these examples.

<Synthesis of Allophanate / Isocyanurate Catalyst (A)>
<Synthesis Example 1>
To a four-necked flask with a capacity of 300 ml equipped with a stirrer, a thermometer, a cooling pipe, and a gas introduction pipe, zinc (II) octylate (trade name: Nikka Octix zinc, divalent / tetravalent = 98/2, 100 g of Nippon Chemical Industry Co., Ltd. was charged, and the temperature was raised to 80 ° C. with stirring. After reaching 80 ° C., high purity oxygen gas was introduced at a flow rate of 20 ml / min and maintained at 80 ° C. for 36 hours to obtain an allophanate / isocyanurate-forming catalyst Cat-1.
The allophanate / isocyanurate catalyst Cat-1 was calculated by calculating the tetravalent zinc content from the total zinc content and the divalent zinc content by the iodine solution titration method. = 55/45. The appearance was a pale yellow liquid, the number of colors was 30 APHA, the viscosity at 25 ° C. was 300 mPa · s, and the turbidity was 0.

<Synthesis Example 2>
In a four-necked flask with a capacity of 300 ml equipped with a stirrer, a thermometer, a cooling pipe, and a gas introduction pipe, tin (II) octylate (trade name: Nikka Octix Tin, divalent / tetravalent = 97/3, 100 g of Nippon Chemical Industry Co., Ltd. was charged, and the temperature was raised to 80 ° C. with stirring. After reaching 80 ° C., high purity oxygen gas was introduced at a flow rate of 20 ml / min, and maintained at 80 ° C. for 36 hours to obtain an allophanate isocyanurate-forming catalyst Cat-2.
The allophanate / isocyanuration catalyst Cat-2 was obtained by calculating the tetravalent tin content from the total tin content and the divalent tin content by the measurement method of the iodine solution titration method. = 57/43. The appearance was a pale yellow liquid, the number of colors was 90 APHA, the viscosity at 25 ° C. was 390 mPa · s, and the turbidity was 0.

<Synthesis Example 3>
In a four-necked flask with a capacity of 300 ml equipped with a stirrer, thermometer, cooling pipe, and gas introduction pipe, zirconium (II) octylate (trade name: Nikka Octix Zirconium, divalent / tetravalent = 99/1, 100 g of Nippon Chemical Industry Co., Ltd. and 100 g of mineral spirit A (manufactured by JX Nippon Mining & Energy Corporation) were charged and heated to 80 ° C. while stirring. After uniformly dissolving and reaching 80 ° C., high purity oxygen gas was introduced at a flow rate of 20 ml / min, and maintained at 80 ° C. for 42 hours to obtain an allophanate isocyanurate-forming catalyst Cat-3.
The allophanate / isocyanurate catalyst Cat-3 was calculated by calculating the tetravalent zirconium content from the total zirconium content and the divalent zirconium content by the iodine solution titration method. = 60/40. The appearance was a pale yellow liquid, the number of colors was 90 APHA, the viscosity at 25 ° C. was 60 mPa · s, and the turbidity was 0.

<Synthesis Example 4>
Zinc acetate (II) (trade name: anhydrous zinc acetate, divalent / tetravalent = 99/1, Kanto Chemical Co., Inc.) in a four-necked flask with a capacity of 300 ml equipped with a stirrer, thermometer, cooling pipe, and gas introduction pipe. 100 g) and ethanol (100 g) were added, and the temperature was raised to 40 ° C. while stirring. After evenly dissolving and reaching 40 ° C., high purity oxygen gas was introduced at a flow rate of 20 ml / min and maintained at 40 ° C. for 36 hours to obtain an allophanate isocyanurate catalyst Cat-4.
The allophanate / isocyanuration catalyst Cat-4 was calculated by calculating the tetravalent zinc content from the total zinc content and the divalent zinc content by the iodine solution titration method. = 59/41. The appearance was a pale yellow liquid, the number of colors was 150 APHA, the viscosity at 25 ° C. was 20 mPa · s, and the turbidity was 0.

<Synthesis Example 5>
Zinc naphthenate (II) (trade name: naphthex zinc, divalent / tetravalent = 98/2, Nippon Chemical Co., Ltd.) in a four-necked flask with a capacity of 300 ml equipped with a stirrer, thermometer, cooling pipe, and gas introduction pipe 100 g of Sangyo Co., Ltd. and 100 g of mineral spirit A were charged and heated to 80 ° C. while stirring. After uniformly dissolving and reaching 80 ° C., high purity oxygen gas was introduced at a flow rate of 20 ml / min and maintained at 80 ° C. for 48 hours to obtain an allophanate / isocyanurate catalyst Cat-5.
The allophanate / isocyanuration catalyst Cat-5 was obtained by calculating the tetravalent zinc content from the total zinc content and the divalent zinc content by the measurement method of the iodine solution titration method. = 62/38. The appearance was a yellow liquid, the number of colors was 250 APHA, the viscosity at 25 ° C. was 70 mPa · s, and the turbidity was 0.

<Synthesis Example 6>
To a 300 ml four-necked flask equipped with a stirrer, thermometer, cooling pipe, and gas introduction pipe, zinc benzoate (II) [trade name: zinc benzoate (II), divalent / tetravalent = 97 / 3, Mitsuwa Chemicals Co., Ltd.] and 100 g of toluene were charged, and the temperature was raised to 80 ° C. with stirring. After uniformly dissolving and reaching 80 ° C., high-purity oxygen gas was introduced at a flow rate of 20 ml / min and maintained at 80 ° C. for 42 hours to obtain an allophanate isocyanurate catalyst Cat-6.
The allophanate / isocyanuration catalyst Cat-6 was obtained by calculating the tetravalent zinc content from the total zinc content and the divalent zinc content by the measurement method of the iodine solution titration method. = 60/40. The appearance was a pale yellow liquid, the number of colors was 150 APHA, the viscosity at 25 ° C. was 30 mPa · s, and the turbidity was 0.

<Synthesis Example 7>
In a 300 ml four-necked flask equipped with a stirrer, a thermometer, a cooling pipe, and a gas introduction pipe, zinc oleate (trade name: zinc oleate (II), divalent / tetravalent = 99 / 1 manufactured by Mitsuwa Chemicals Co., Ltd.] and 100 g of toluene were charged, and the temperature was raised to 80 ° C. while stirring. After uniformly dissolving and reaching 80 ° C., high purity oxygen gas was introduced at a flow rate of 20 ml / min and maintained at 80 ° C. for 36 hours to obtain an allophanate isocyanurate catalyst Cat-7.
The allophanate / isocyanuration catalyst Cat-7 was calculated by calculating the tetravalent zinc content from the total zinc content and divalent zinc content by the iodine solution titration method. = 63/37. The appearance was a pale yellow liquid, the number of colors was 120 APHA, the viscosity at 25 ° C. was 20 mPa · s, and the turbidity was 0.

<Synthesis Example 8>
100 g of tin (II) octylate (divalent / tetravalent = 97/3) was charged into a four-necked flask having a capacity of 300 ml equipped with a stirrer, a thermometer, a cooling pipe, and a gas introduction pipe, and stirred with stirring. The temperature was raised to ° C. After reaching 80 ° C., high purity oxygen gas was introduced at a flow rate of 20 ml / min and maintained at 80 ° C. for 1 hour to obtain an allophanate isocyanurate-catalyzing catalyst Cat-8.
The allophanate / isocyanuration catalyst Cat-8 was calculated by calculating the tetravalent tin content from the total tin content and the divalent tin content by the iodine solution titration method. = 95/5. The appearance was a pale yellow liquid, the number of colors was 90 APHA, the viscosity at 25 ° C. was 390 mPa · s, and the turbidity was 0.

<Synthesis Example 9>
100 g of tin (II) octylate (divalent / tetravalent = 97/3) was charged into a four-necked flask having a capacity of 300 ml equipped with a stirrer, a thermometer, a cooling pipe, and a gas introduction pipe, and stirred with stirring. The temperature was raised to ° C. After reaching 80 ° C., high purity oxygen gas was introduced at a flow rate of 20 ml / min and maintained at 80 ° C. for 2 hours to obtain an allophanate isocyanurate catalyst Cat-9.
Allophanate / isocyanurate catalyst Cat-9 was calculated by calculating the tetravalent tin content from the total tin content and the divalent tin content by the iodine solution titration method. = 90/10. The appearance was a pale yellow liquid, the number of colors was 90 APHA, the viscosity at 25 ° C. was 390 mPa · s, and the turbidity was 0.

<Synthesis Example 10>
100 g of tin (II) octylate (divalent / tetravalent = 97/3) was charged into a four-necked flask having a capacity of 300 ml equipped with a stirrer, a thermometer, a cooling pipe, and a gas introduction pipe, and stirred with stirring. The temperature was raised to ° C. After reaching 80 ° C., high-purity oxygen gas was introduced at a flow rate of 20 ml / min and maintained at 80 ° C. for 60 hours to obtain an allophanate isocyanurate catalyst Cat-10.
The allophanate / isocyanuration catalyst Cat-10 was obtained by calculating the tetravalent tin content from the total tin content and the divalent tin content by the measurement method of the iodine solution titration method. = 0/100. The appearance was a pale yellow liquid, the number of colors was 90 APHA, the viscosity at 25 ° C. was 430 mPa · s, and the turbidity was 0.

Table 1 shows the properties of the allophanate isocyanurate-forming catalysts Cat-1 to Cat-10.

<Synthesis of polyisocyanate composition>
<Example 1>
In a 2 liter four-necked flask equipped with a stirrer, a thermometer, a cooling tube, and a nitrogen gas introduction tube, hexamethylene diisocyanate HDI-1 (NCO content: 49.9% by mass, hydrolyzable chlorine content: 221.5ppm) and decane of tridecanol (manufactured by Kyowa Hakko Chemical Co., Ltd.) 120g, heated to 85 ° C with stirring under a nitrogen stream, and subjected to urethanization for 3 hours to obtain isocyanate group-terminated prepolymer I It was. Thereafter, 0.4 g of allophanate / isocyanurate catalyst Cat-1 was added to this isocyanate group-terminated prepolymer I, and the allophanate reaction and isocyanate were carried out at 110 ° C. until the molar ratio of allophanate groups / isocyanurate groups was 50/50. A nurating reaction was performed. Thereafter, 0.5 g of JP-508 (manufactured by Johoku Chemical Industry Co., Ltd., acidic phosphate ester) was added, a termination reaction was performed, and the reaction solution was cooled to room temperature to obtain isocyanate-terminated prepolymer II. The isocyanate-terminated prepolymer II was subjected to thin-film distillation at 130 ° C. × 0.04 kPa to remove unreacted HDI, thereby obtaining a purified polyisocyanate composition PI-1.
The polyisocyanate composition PI-1 has an NCO content of 16.2% by mass, a transparent appearance, a number average molecular weight of 860, a viscosity at 25 ° C. of 700 mPa · s, and a free HDI content of 0.2% by mass. there were. In addition, the allophanate group content in all linking groups was 49 mol%, the nurate group content was 51 mol%, and the urethane group content was 0 mol%.

<Method for measuring hydrolyzable chlorine>
The method for measuring hydrolyzable chlorine was determined by potentiometric titration with the following standard solution of silver nitrate according to JIS K1603-3 "Plastics-Polyurethane raw material aromatic isocyanate test method-Part 3: Determination of hydrolyzable chlorine". It is done.
(1) About 10 g of a sample is weighed into a 500 ml Erlenmeyer flask, and 50 ml of methanol is added and stirred. When crystals begin to precipitate on the side of the Erlenmeyer flask, add 200 ml of distilled water and boil for 30 minutes.
(2) After completion of boiling, cool to about 10 ° C. in an ice bath, add 10 drops of nitric acid, and perform potentiometric titration with a silver nitrate standard solution.
<Calculation of hydrolyzable chlorine content: H (%)>
Hydrolyzable chlorine is calculated in mass% as in the following formula, and then converted into units as appropriate.
H = 3.55 × V × c / m
(1) H: Hydrolyzable chlorine (mass%)
(2) V: amount of silver nitrate solution required for titration of sample (ml)
(3) c: concentration of silver nitrate solution (mol / l)
(4) m: Mass of the sample (g)
(5) 3.55: Coefficient (g / mol) combining chlorine atomic weight (35.5 g / mol), mg to g conversion coefficient (1000), and mass% conversion coefficient (100).

<NMR: measurement of allophanate group / nurate group / urethane group content>
(1) Measuring device: ECX400M (manufactured by JEOL Ltd., 1H-NMR)
(2) Measurement temperature: 23 ° C
(3) Sample concentration: 0.1 g / 1 ml
(4) Integration count: 16
(5) Relaxation time: 5 seconds (6) Solvent: Deuterium dimethyl sulfoxide (7) Chemical shift criteria: Hydrogen atom signal of methyl group in deuterium dimethyl sulfoxide (2.5 ppm)
(8) Evaluation method: signal of hydrogen atom bonded to nitrogen atom of allophanate group near 8.5 ppm, signal of hydrogen atom of methylene group adjacent to nitrogen atom of nurate group near 3.7 ppm, and around 7.0 ppm The content of the linking group was measured from the area ratio of the signal of the hydrogen atom bonded to the nitrogen atom of the urethane group.

<GPC: Measurement of molecular weight>
(1) Measuring instrument: HLC-8220 (manufactured by Tosoh Corporation)
(2) Column: TSKgel (manufactured by Tosoh Corporation)
・ G3000H-XL
・ G2500H-XL
・ G2000H-XL, G1000H-XL
(3) Carrier: THF (tetrahydrofuran)
(4) Detector: RI (refractive index) detector (5) Temperature: 40 ° C
(6) Flow rate: 1.000 ml / min
(7) Calibration curve: Standard polystyrene (manufactured by Tosoh Corporation)
F-80 (molecular weight: 7.06 × 10 ⁵ , molecular weight distribution: 1.05)
F-20 (molecular weight: 1.90 × 10 ⁵ , molecular weight distribution: 1.05)
F-10 (molecular weight: 9.64 × 10 ⁴ , molecular weight distribution: 1.01)
F-2 (molecular weight: 1.81 × 10 ⁴ , molecular weight distribution: 1.01)
F-1 (molecular weight: 1.02 × 10 ⁴ , molecular weight distribution: 1.02)
A-5000 (molecular weight: 5.97 × 10 ³ , molecular weight distribution: 1.02)
A-2500 (molecular weight: 2.63 × 10 ³ , molecular weight distribution: 1.05)
A-500 (molecular weight: 5.0 × 10 ² , molecular weight distribution: 1.14)
(8) Sample solution concentration: 0.5% THF solution

<Example 2>
A 2-liter four-necked flask equipped with a stirrer, thermometer, cooling pipe, and nitrogen gas introduction pipe was charged with 880 g of HDI-1 and 120 g of tridecanol and heated to 85 ° C. with stirring under a nitrogen stream. An isocyanate group-terminated prepolymer I was obtained by performing a urethanization reaction for 3 hours. Thereafter, 0.4 g of allophanate / isocyanurate catalyst Cat-2 was added to this isocyanate group-terminated prepolymer I, and the allophanate reaction and isocyanate were carried out at 110 ° C. until the molar ratio of allophanate groups / isocyanurate groups was 50/50. A nurating reaction was performed. Thereafter, 0.5 g of JP-508 was added to stop the reaction, and the reaction solution was cooled to room temperature to obtain an isocyanate-terminated prepolymer II. The isocyanate-terminated prepolymer II was subjected to thin-film distillation at 130 ° C. × 0.04 kPa to remove unreacted HDI, thereby obtaining a purified polyisocyanate composition PI-2.
The polyisocyanate composition PI-2 has an NCO content of 16.4% by mass, a transparent appearance, a number average molecular weight of 850, a viscosity at 25 ° C. of 720 mPa · s, and a free HDI content of 0.2% by mass. there were. In addition, the allophanate group content in all linking groups was 50 mol%, the nurate group content was 50 mol%, and the urethane group content was 0 mol%.

<Example 3>
A 2-liter four-necked flask equipped with a stirrer, thermometer, cooling pipe, and nitrogen gas introduction pipe was charged with 880 g of HDI-1 and 120 g of tridecanol and heated to 85 ° C. with stirring under a nitrogen stream. An isocyanate group-terminated prepolymer I was obtained by performing a urethanization reaction for 3 hours. Thereafter, 0.8 g of the allophanate / isocyanurate catalyst Cat-3 was added to the isocyanate group-terminated prepolymer I, and the allophanate reaction and isocyanate were carried out at 110 ° C. until the molar ratio of allophanate groups / isocyanurate groups was 50/50. A nurating reaction was performed. Thereafter, 0.5 g of JP-508 was added to stop the reaction, and the reaction solution was cooled to room temperature to obtain an isocyanate-terminated prepolymer II. This isocyanate-terminated prepolymer II was thin-film distilled at 130 ° C. × 0.04 kPa to remove unreacted HDI, thereby obtaining a purified polyisocyanate composition PI-3.
The polyisocyanate composition PI-3 has an NCO content of 16.5% by mass, an appearance that is a transparent liquid, a number average molecular weight of 860, a viscosity at 25 ° C. of 710 mPa · s, and a free HDI content of 0.4% by mass. there were. In addition, the allophanate group content in all linking groups was 48 mol%, the nurate group content was 52 mol%, and the urethane group content was 0 mol%.

<Example 4>
A 2-liter four-necked flask equipped with a stirrer, thermometer, cooling pipe, and nitrogen gas introduction pipe was charged with 880 g of HDI-1 and 120 g of tridecanol and heated to 85 ° C. with stirring under a nitrogen stream. An isocyanate group-terminated prepolymer I was obtained by performing a urethanization reaction for 3 hours. Thereafter, 0.8 g of the allophanate / isocyanurate catalyst Cat-4 was added to the isocyanate group-terminated prepolymer I, and the allophanate reaction and isocyanate were performed at 110 ° C. until the allophanate group / isocyanurate group molar ratio reached 50/50. A nurating reaction was performed. Thereafter, 0.5 g of JP-508 was added to stop the reaction, and the reaction solution was cooled to room temperature to obtain an isocyanate-terminated prepolymer II. The isocyanate-terminated prepolymer II was subjected to thin-film distillation at 130 ° C. × 0.04 kPa to remove unreacted HDI, thereby obtaining a purified polyisocyanate composition PI-4.
The polyisocyanate composition PI-4 has an NCO content of 16.4% by mass, a transparent appearance, a number average molecular weight of 870, a viscosity at 25 ° C. of 690 mPa · s, and a free HDI content of 0.2% by mass. there were. In addition, the allophanate group content in all linking groups was 51 mol%, the nurate group content was 48 mol%, and the urethane group content was 1 mol%.

<Example 5>
A 2-liter four-necked flask equipped with a stirrer, thermometer, cooling pipe, and nitrogen gas introduction pipe was charged with 880 g of HDI-1 and 120 g of tridecanol and heated to 85 ° C. with stirring under a nitrogen stream. An isocyanate group-terminated prepolymer I was obtained by performing a urethanization reaction for 3 hours. Thereafter, 0.8 g of the allophanate isocyanurate catalyst Cat-5 was added to the isocyanate group-terminated prepolymer I, and the allophanate reaction and isocyanate were performed at 110 ° C. until the molar ratio of allophanate groups / isocyanurate groups was 50/50. A nurating reaction was performed. Thereafter, 0.5 g of JP-508 was added to stop the reaction, and the reaction solution was cooled to room temperature to obtain an isocyanate-terminated prepolymer II. This isocyanate-terminated prepolymer II was subjected to thin-film distillation at 130 ° C. × 0.04 kPa to remove unreacted HDI, thereby obtaining a purified polyisocyanate composition PI-5.
The polyisocyanate composition PI-5 has an NCO content of 16.3% by mass, an appearance of a transparent liquid, a number average molecular weight of 860, a viscosity at 25 ° C. of 700 mPa · s, and a free HDI content of 0.4% by mass. there were. In addition, the allophanate group content in all linking groups was 50 mol%, the nurate group content was 50 mol%, and the urethane group content was 0 mol%.

<Example 6>
A 2-liter four-necked flask equipped with a stirrer, thermometer, cooling pipe, and nitrogen gas introduction pipe was charged with 880 g of HDI-1 and 120 g of tridecanol and heated to 85 ° C. with stirring under a nitrogen stream. An isocyanate group-terminated prepolymer I was obtained by performing a urethanization reaction for 3 hours. Thereafter, 0.8 g of the allophanate isocyanurate catalyst Cat-6 was added to the isocyanate group-terminated prepolymer I, and the allophanate reaction and isocyanate were performed until the allophanate group / isocyanurate group molar ratio reached 50/50 at 110 ° C. A nurating reaction was performed. Thereafter, 0.5 g of JP-508 was added to stop the reaction, and the reaction solution was cooled to room temperature to obtain an isocyanate-terminated prepolymer II. The isocyanate-terminated prepolymer II was subjected to thin-film distillation at 130 ° C. × 0.04 kPa to remove unreacted HDI, thereby obtaining a purified polyisocyanate composition PI-6.
The polyisocyanate composition PI-6 has an NCO content of 16.4% by mass, a transparent appearance, a number average molecular weight of 860, a viscosity at 25 ° C. of 710 mPa · s, and a free HDI content of 0.4% by mass. there were. In addition, the allophanate group content in all linking groups was 48 mol%, the nurate group content was 49 mol%, and the urethane group content was 3 mol%.

<Example 7>
A 2-liter four-necked flask equipped with a stirrer, thermometer, cooling pipe, and nitrogen gas introduction pipe was charged with 880 g of HDI-1 and 120 g of tridecanol and heated to 85 ° C. with stirring under a nitrogen stream. An isocyanate group-terminated prepolymer I was obtained by performing a urethanization reaction for 3 hours. Thereafter, 0.8 g of the allophanate isocyanurate catalyst Cat-7 was added to this isocyanate group-terminated prepolymer I, and the allophanate reaction and isocyanate were performed until the molar ratio of allophanate groups / isocyanurate groups was 50/50 at 110 ° C. A nurating reaction was performed. Thereafter, 0.5 g of JP-508 was added to stop the reaction, and the reaction solution was cooled to room temperature to obtain an isocyanate-terminated prepolymer II. The isocyanate-terminated prepolymer II was subjected to thin-film distillation at 130 ° C. × 0.04 kPa to remove unreacted HDI, thereby obtaining a purified polyisocyanate composition PI-7.
The polyisocyanate composition PI-7 has an NCO content of 16.3% by mass, an appearance of a transparent liquid, a number average molecular weight of 860, a viscosity at 25 ° C. of 720 mPa · s, and a free HDI content of 0.2% by mass. there were. In addition, the allophanate group content in all linking groups was 50 mol%, the nurate group content was 50 mol%, and the urethane group content was 0 mol%.

<Example 8>
In a 2 liter four-necked flask equipped with a stirrer, a thermometer, a cooling pipe, and a nitrogen gas introduction pipe, hexamethylene diisocyanate HDI-2 (NCO content: 49.9% by mass, hydrolyzable chlorine content: 30.0 ppm) and 120 g of tridecanol were charged, heated to 85 ° C. with stirring under a nitrogen stream, and subjected to urethanization for 3 hours to obtain an isocyanate group-terminated prepolymer I. Thereafter, 0.4 g of allophanate / isocyanurate catalyst Cat-2 was added to this isocyanate group-terminated prepolymer I, and the allophanate reaction and isocyanate were carried out at 110 ° C. until the molar ratio of allophanate groups / isocyanurate groups was 50/50. A nurating reaction was performed. Thereafter, 0.5 g of JP-508 was added to stop the reaction, and the reaction solution was cooled to room temperature to obtain an isocyanate-terminated prepolymer II. This isocyanate-terminated prepolymer II was subjected to thin-film distillation at 130 ° C. × 0.04 kPa to remove unreacted HDI, thereby obtaining a purified polyisocyanate composition PI-8.
The polyisocyanate composition PI-8 has an NCO content of 16.4% by mass, a transparent appearance, a number average molecular weight of 860, a viscosity at 25 ° C. of 690 mPa · s, and a free HDI content of 0.2% by mass. there were. Further, the allophanate group content in all the linking groups was 51 mol%, the nurate group content was 47 mol%, and the urethane group content was 2 mol%.

<Example 9>
In a 2 liter four-necked flask equipped with a stirrer, a thermometer, a cooling tube, and a nitrogen gas introduction tube, hexamethylene diisocyanate HDI-3 (NCO content: 49.9% by mass, hydrolyzable chlorine content: 105.4 ppm) and 120 g of tridecanol were charged, and the mixture was heated to 85 ° C. with stirring under a nitrogen stream and subjected to a urethanization reaction for 3 hours to obtain an isocyanate group-terminated prepolymer I. Thereafter, 0.4 g of allophanate / isocyanurate catalyst Cat-2 was added to this isocyanate group-terminated prepolymer I, and the allophanate reaction and isocyanate were carried out at 110 ° C. until the molar ratio of allophanate groups / isocyanurate groups was 50/50. A nurating reaction was performed. Thereafter, 0.5 g of JP-508 was added to stop the reaction, and the reaction solution was cooled to room temperature to obtain an isocyanate-terminated prepolymer II. This isocyanate-terminated prepolymer II was subjected to thin-film distillation at 130 ° C. × 0.04 kPa to remove unreacted HDI, thereby obtaining a purified polyisocyanate composition PI-9.
The polyisocyanate composition PI-9 has an NCO content of 16.7% by mass, an appearance that is a transparent liquid, a number average molecular weight of 860, a viscosity at 25 ° C. of 700 mPa · s, and a free HDI content of 0.4% by mass. there were. In addition, the allophanate group content in all linking groups was 49 mol%, the nurate group content was 48 mol%, and the urethane group content was 3 mol%.

<Example 10>
A 2-liter four-necked flask equipped with a stirrer, thermometer, cooling pipe, and nitrogen gas introduction pipe was charged with 880 g of HDI-1 and 120 g of tridecanol and heated to 85 ° C. with stirring under a nitrogen stream. An isocyanate group-terminated prepolymer I was obtained by performing a urethanization reaction for 3 hours. Thereafter, 0.4 g of allophanate isocyanurate catalyst Cat-8 was added to this isocyanate group-terminated prepolymer I, and allophanate reaction and isocyanate were performed at 110 ° C. until the molar ratio of allophanate groups / isocyanurate groups was 50/50. A nurating reaction was performed. Thereafter, the reaction did not proceed before the molar ratio of allophanate group / isocyanurate group reached 50/50. Therefore, 0.5 g of JP-508 was added, a stop reaction was performed, the reaction solution was cooled to room temperature, and isocyanate was added. Terminal prepolymer II was obtained. This isocyanate-terminated prepolymer II was thin-film distilled at 130 ° C. × 0.04 kPa to remove unreacted HDI, thereby obtaining a purified polyisocyanate composition PI-10.
Polyisocyanate composition PI-10 has an NCO content of 15.7% by mass, an external appearance of a transparent liquid, a number average molecular weight of 760, a viscosity at 25 ° C. of 550 mPa · s, and a free HDI content of 0.1% by mass. there were. In addition, the allophanate group content in all linking groups was 65 mol%, the nurate group content was 34 mol%, and the urethane group content was 1 mol%.

<Example 11>
A 2-liter four-necked flask equipped with a stirrer, thermometer, cooling pipe, and nitrogen gas introduction pipe was charged with 880 g of HDI-1 and 120 g of tridecanol and heated to 85 ° C. with stirring under a nitrogen stream. An isocyanate group-terminated prepolymer I was obtained by performing a urethanization reaction for 3 hours. Thereafter, 0.4 g of allophanate isocyanurate catalyst Cat-9 was added to this isocyanate group-terminated prepolymer I, and the allophanate reaction and isocyanate were performed at 110 ° C. until the molar ratio of allophanate groups / isocyanurate groups was 50/50. A nurating reaction was performed. Thereafter, 0.5 g of JP-508 was added to stop the reaction, and the reaction solution was cooled to room temperature to obtain an isocyanate-terminated prepolymer II. This isocyanate-terminated prepolymer II was subjected to thin-film distillation at 130 ° C. × 0.04 kPa to remove unreacted HDI, thereby obtaining a purified polyisocyanate composition PI-11.
The polyisocyanate composition PI-11 has an NCO content of 16.2% by mass, a transparent appearance, a number average molecular weight of 790, a viscosity at 25 ° C. of 600 mPa · s, and a free HDI content of 0.1% by mass. there were. In addition, the allophanate group content in all linking groups was 54 mol%, the nurate group content was 45 mol%, and the urethane group content was 1 mol%.

<Example 12>
A 2-liter four-necked flask equipped with a stirrer, thermometer, cooling pipe, and nitrogen gas introduction pipe was charged with 880 g of HDI-1 and 120 g of tridecanol and heated to 85 ° C. with stirring under a nitrogen stream. An isocyanate group-terminated prepolymer I was obtained by performing a urethanization reaction for 3 hours. Thereafter, 0.4 g of allophanate / isocyanurate catalyst Cat-10 was added to this isocyanate group-terminated prepolymer I, and the allophanate reaction and isocyanate were performed at 110 ° C. until the molar ratio of allophanate groups / isocyanurate groups was 50/50. A nurating reaction was performed. Thereafter, 0.5 g of JP-508 was added to stop the reaction, and the reaction solution was cooled to room temperature to obtain an isocyanate-terminated prepolymer II. This isocyanate-terminated prepolymer II was subjected to thin-film distillation at 130 ° C. × 0.04 kPa to remove unreacted HDI, thereby obtaining a purified polyisocyanate composition PI-12.
The polyisocyanate composition PI-12 has an NCO content of 16.4% by mass, a transparent appearance, a number average molecular weight of 850, a viscosity at 25 ° C. of 730 mPa · s, and a free HDI content of 0.3% by mass. there were. In addition, the allophanate group content in all linking groups was 50 mol%, the nurate group content was 50 mol%, and the urethane group content was 0 mol%.

<Example 13>
950 g of HDI-1 and 50 g of 2-propanol (IPA) were charged into a 2-liter four-necked flask equipped with a stirrer, thermometer, cooling pipe, and nitrogen gas introduction pipe while stirring under a nitrogen stream. The isocyanate group terminal prepolymer I was obtained by heating to 85 degreeC and performing a urethanation reaction for 3 hours. Thereafter, 0.4 g of allophanate / isocyanurate catalyst Cat-2 was added to this isocyanate group-terminated prepolymer I, and allophanate reaction and A nurating reaction was performed. Thereafter, 0.5 g of JP-508 was added to stop the reaction, and the reaction solution was cooled to room temperature to obtain an isocyanate-terminated prepolymer II. This isocyanate-terminated prepolymer II was subjected to thin-film distillation at 130 ° C. × 0.04 kPa to remove unreacted HDI, thereby obtaining a purified polyisocyanate composition PI-13.
Polyisocyanate composition PI-13 has an NCO content of 19.3% by mass, an external appearance that is a transparent liquid, a number average molecular weight of 580, a viscosity at 25 ° C. of 370 mPa · s, and a free HDI content of 0.1% by mass. there were. Further, the allophanate group content in all the linking groups was 75 mol%, the nurate group content was 24 mol%, and the urethane group content was 1 mol%.

<Example 14>
A 2-liter four-necked flask equipped with a stirrer, thermometer, cooling pipe, and nitrogen gas introduction pipe was charged with 910 g of HDI-1 and 90 g of 2-ethylhexanol, and stirred at 85 ° C. under a nitrogen stream. And an urethanization reaction was carried out for 3 hours to obtain an isocyanate group-terminated prepolymer I. Thereafter, 0.4 g of allophanate / isocyanurate catalyst Cat-2 was added to this isocyanate group-terminated prepolymer I, and allophanate reaction and A nurating reaction was performed. Thereafter, 0.5 g of JP-508 was added to stop the reaction, and the reaction solution was cooled to room temperature to obtain an isocyanate-terminated prepolymer II. This isocyanate-terminated prepolymer II was subjected to thin-film distillation at 130 ° C. × 0.04 kPa to remove unreacted HDI, thereby obtaining a purified polyisocyanate composition PI-14.
Polyisocyanate composition PI-14 has an NCO content of 17.4% by mass, an appearance that is a transparent liquid, a number average molecular weight of 670, a viscosity at 25 ° C. of 380 mPa · s, and a free HDI content of 0.1% by mass. there were. In addition, the allophanate group content in all linking groups was 78 mol%, the nurate group content was 22 mol%, and the urethane group content was 0 mol%.

<Example 15>
A 2-liter four-necked flask equipped with a stirrer, thermometer, cooling pipe, and nitrogen gas introduction pipe was charged with 880 g of HDI-1 and 120 g of tridecanol and heated to 85 ° C. with stirring under a nitrogen stream. An isocyanate group-terminated prepolymer I was obtained by performing a urethanization reaction for 3 hours. Thereafter, 0.4 g of allophanate / isocyanurate catalyst Cat-2 was added to this isocyanate group-terminated prepolymer I, and allophanate reaction and A nurating reaction was performed. Thereafter, 0.5 g of JP-508 was added to stop the reaction, and the reaction solution was cooled to room temperature to obtain an isocyanate-terminated prepolymer II. This isocyanate-terminated prepolymer II was thin-film distilled at 130 ° C. × 0.04 kPa to remove unreacted HDI, thereby obtaining a purified polyisocyanate composition PI-15.
The polyisocyanate composition PI-15 has an NCO content of 15.8% by mass, an appearance that is a transparent liquid, a number average molecular weight of 740, a viscosity at 25 ° C. of 420 mPa · s, and a free HDI content of 0.1% by mass. there were. Further, the allophanate group content in all the linking groups was 76 mol%, the nurate group content was 24 mol%, and the urethane group content was 0 mol%.

<Example 16>
850 g of HDI-1 and 2-octyldodecanol (trade name: Calcoal 200GD, manufactured by Kao Corporation) in a 2 liter four-necked flask equipped with a stirrer, thermometer, cooling pipe, and nitrogen gas introduction pipe An isocyanate group-terminated prepolymer I was obtained by charging 150 g, heating to 85 ° C. with stirring under a nitrogen stream, and performing a urethanization reaction for 3 hours. Thereafter, 0.4 g of allophanate / isocyanurate catalyst Cat-2 was added to this isocyanate group-terminated prepolymer I, and allophanate reaction and A nurating reaction was performed. Thereafter, 0.5 g of JP-508 was added to stop the reaction, and the reaction solution was cooled to room temperature to obtain an isocyanate-terminated prepolymer II. The isocyanate-terminated prepolymer II was subjected to thin-film distillation at 130 ° C. × 0.04 kPa to remove unreacted HDI, thereby obtaining a purified polyisocyanate composition PI-16.
The polyisocyanate composition PI-16 has an NCO content of 15.2% by mass, an appearance of a transparent liquid, a number average molecular weight of 960, a viscosity at 25 ° C. of 460 mPa · s, and a free HDI content of 0.2% by mass. there were. Further, the allophanate group content in all the linking groups was 76 mol%, the nurate group content was 24 mol%, and the urethane group content was 0 mol%.

<Example 17>
A 2-liter four-necked flask equipped with a stirrer, thermometer, cooling pipe, and nitrogen gas introduction pipe was charged with 880 g of HDI-1 and 120 g of tridecanol and heated to 85 ° C. with stirring under a nitrogen stream. An isocyanate group-terminated prepolymer I was obtained by performing a urethanization reaction for 3 hours. Thereafter, 0.4 g of allophanate isocyanurate catalyst Cat-2 was added to this isocyanate group-terminated prepolymer I, and allophanate reaction and isocyanate were performed at 110 ° C. until the molar ratio of allophanate groups / isocyanurate groups was 85/15. A nurating reaction was performed. Thereafter, 0.5 g of JP-508 was added to stop the reaction, and the reaction solution was cooled to room temperature to obtain an isocyanate-terminated prepolymer II. The isocyanate-terminated prepolymer II was subjected to thin-film distillation at 130 ° C. × 0.04 kPa to remove unreacted HDI, thereby obtaining a purified polyisocyanate composition PI-17.
Polyisocyanate composition PI-17 has an NCO content of 15.2% by mass, an external appearance that is a transparent liquid, a number average molecular weight of 700, a viscosity at 25 ° C. of 330 mPa · s, and a free HDI content of 0.1% by mass. there were. In addition, the allophanate group content in all linking groups was 82 mol%, the nurate group content was 18 mol%, and the urethane group content was 0 mol%.

<Example 18>
A 2-liter four-necked flask equipped with a stirrer, thermometer, cooling tube, and nitrogen gas introduction tube was charged with 980 g of HDI-1 and 20 g of tridecanol, and heated to 85 ° C. with stirring under a nitrogen stream. An isocyanate group-terminated prepolymer I was obtained by performing a urethanization reaction for 3 hours. Thereafter, 0.4 g of allophanate / isocyanurate catalyst Cat-2 was added to this isocyanate group-terminated prepolymer I, and the allophanate reaction and isocyanate were performed at 110 ° C. until the molar ratio of allophanate group / isocyanurate group was 30/70. A nurating reaction was performed. Thereafter, 0.5 g of JP-508 was added to stop the reaction, and the reaction solution was cooled to room temperature to obtain an isocyanate-terminated prepolymer II. This isocyanate-terminated prepolymer II was thin-film distilled at 130 ° C. × 0.04 kPa to remove unreacted HDI, thereby obtaining a purified polyisocyanate composition PI-18.
The polyisocyanate composition PI-18 has an NCO content of 21.0% by mass, an appearance that is a transparent liquid, a number average molecular weight of 600, a viscosity at 25 ° C. of 360 mPa · s, and a free HDI content of 0.1% by mass. there were. In addition, the allophanate group content in all linking groups was 35 mol%, the nurate group content was 65 mol%, and the urethane group content was 0 mol%.

<Example 19>
A 2-liter four-necked flask equipped with a stirrer, thermometer, cooling tube, and nitrogen gas introduction tube was charged with 980 g of HDI-1 and 20 g of tridecanol, and heated to 85 ° C. with stirring under a nitrogen stream. An isocyanate group-terminated prepolymer I was obtained by performing a urethanization reaction for 3 hours. Thereafter, 0.4 g of allophanate / isocyanurate catalyst Cat-2 was added to this isocyanate group-terminated prepolymer I and allophanate reaction and A nurating reaction was performed. Thereafter, 0.5 g of JP-508 was added to stop the reaction, and the reaction solution was cooled to room temperature to obtain an isocyanate-terminated prepolymer II. This isocyanate-terminated prepolymer II was subjected to thin-film distillation at 130 ° C. × 0.04 kPa to remove unreacted HDI, thereby obtaining a purified polyisocyanate composition PI-19.
The polyisocyanate composition PI-19 has an NCO content of 21.4% by mass, an appearance that is a transparent liquid, a number average molecular weight of 620, a viscosity at 25 ° C. of 400 mPa · s, and a free HDI content of 0.2% by mass. there were. In addition, the allophanate group content in all linking groups was 23 mol%, the nurate group content was 77 mol%, and the urethane group content was 0 mol%.

<Comparative Example 1>
A 2-liter four-necked flask equipped with a stirrer, thermometer, cooling pipe, and nitrogen gas introduction pipe was charged with 880 g of HDI-1 and 120 g of tridecanol and heated to 85 ° C. with stirring under a nitrogen stream. An isocyanate group-terminated prepolymer I was obtained by performing a urethanization reaction for 3 hours. Thereafter, 0.4 g of zinc octylate (II) (trade name: Nikka Octix zinc, divalent / tetravalent = 98/2, manufactured by Nippon Kagaku Sangyo Co., Ltd.) was added to the isocyanate group-terminated prepolymer I at 110 ° C. The allophanate reaction and isocyanurate reaction were carried out until the allophanate group / isocyanurate group molar ratio reached 50/50. Thereafter, the reaction did not proceed before the molar ratio of allophanate group / isocyanurate group reached 50/50. Therefore, 0.5 g of JP-508 was added, and the reaction solution was cooled to room temperature to obtain isocyanate-terminated prepolymer II. Obtained. This isocyanate-terminated prepolymer II was subjected to thin-film distillation at 130 ° C. × 0.04 kPa to remove unreacted HDI, thereby obtaining a purified polyisocyanate composition PI-20.
The polyisocyanate composition PI-20 has an NCO content of 14.5% by mass, an appearance that is a transparent liquid, a number average molecular weight of 620, a viscosity at 25 ° C. of 230 mPa · s, and a free HDI content of 0.2% by mass. there were. In addition, the allophanate group content in all linking groups was 92 mol%, the nurate group content was 7 mol%, and the urethane group content was 1 mol%.

<Comparative Example 2>
A 2-liter four-necked flask equipped with a stirrer, thermometer, cooling pipe, and nitrogen gas introduction pipe was charged with 880 g of HDI-1 and 120 g of tridecanol and heated to 85 ° C. with stirring under a nitrogen stream. An isocyanate group-terminated prepolymer I was obtained by performing a urethanization reaction for 3 hours. Thereafter, 0.4 g of tin (II) octylate (trade name: Nikka Octix tin, divalent / tetravalent = 97/3, manufactured by Nippon Kagaku Sangyo Co., Ltd.) was added to the isocyanate group-terminated prepolymer I at 110 ° C. The allophanate reaction and isocyanurate reaction were carried out until the allophanate group / isocyanurate group molar ratio reached 50/50. Thereafter, the reaction did not proceed before the molar ratio of allophanate group / isocyanurate group reached 50/50. Therefore, 0.5 g of JP-508 was added, and the reaction solution was cooled to room temperature to obtain isocyanate-terminated prepolymer II. Obtained. The isocyanate-terminated prepolymer II was subjected to thin-film distillation at 130 ° C. × 0.04 kPa to remove unreacted HDI, thereby obtaining a purified polyisocyanate composition PI-21.
The polyisocyanate composition PI-21 has an NCO content of 14.8% by mass, an appearance of a transparent liquid, a number average molecular weight of 620, a viscosity at 25 ° C. of 290 mPa · s, and a free HDI content of 0.2% by mass. there were. In addition, the allophanate group content in all linking groups was 87 mol%, the nurate group content was 12 mol%, and the urethane group content was 1 mol%.

<Comparative Example 3>
A 2-liter four-necked flask equipped with a stirrer, thermometer, cooling pipe, and nitrogen gas introduction pipe was charged with 880 g of HDI-1 and 120 g of tridecanol and heated to 85 ° C. with stirring under a nitrogen stream. An isocyanate group-terminated prepolymer I was obtained by performing a urethanization reaction for 3 hours. Thereafter, this isocyanate group-terminated prepolymer I and zirconium octylate (II) adjusted to 50% by mass with mineral spirit A (trade name: Nikka Octix Zirconium, divalent / tetravalent = 99/1, Nippon Chemical Industry Co., Ltd.) 0.8 g of a solution (manufactured by Kogyo Co., Ltd.) was added, and an allophanate reaction and isocyanurate reaction were carried out at 110 ° C. until the allophanate group / isocyanurate group molar ratio reached 50/50. Thereafter, the reaction did not proceed before the molar ratio of allophanate group / isocyanurate group reached 50/50. Therefore, 0.5 g of JP-508 was added, and the reaction solution was cooled to room temperature to obtain isocyanate-terminated prepolymer II. Obtained. The isocyanate-terminated prepolymer II was subjected to thin-film distillation at 130 ° C. × 0.04 kPa to remove unreacted HDI, thereby obtaining a purified polyisocyanate composition PI-22.
Polyisocyanate composition PI-22 has an NCO content of 14.4% by mass, an appearance that is a transparent liquid, a number average molecular weight of 600, a viscosity at 25 ° C. of 150 mPa · s, and a free HDI content of 0.2% by mass. there were. Further, the allophanate group content in all the linking groups was 95 mol%, the nurate group content was 3 mol%, and the urethane group content was 1 mol%.

<Comparative Example 4>
A 2-liter four-necked flask equipped with a stirrer, thermometer, cooling pipe, and nitrogen gas introduction pipe was charged with 880 g of HDI-1 and 120 g of tridecanol and heated to 85 ° C. with stirring under a nitrogen stream. An isocyanate group-terminated prepolymer I was obtained by performing a urethanization reaction for 3 hours. Thereafter, 0.2 g of tin (II) octylate (divalent / tetravalent = 97/3) was added to the isocyanate group-terminated prepolymer I, and an allophanatization reaction was performed at 110 ° C. Thereafter, the mixture is cooled to 60 ° C., 0.2 g of 2-hydroxypropyltrimethylammonium octylate (trade name: DABCO TMR, manufactured by Air Products Japan), which is an isocyanurate-forming catalyst, is added, and isocyanuration reaction is performed at 60 ° C. Went. Then, 0.25g of JP-508 was added, the termination reaction was performed, the reaction liquid was cooled to room temperature, and the isocyanate terminal prepolymer II was obtained. This isocyanate-terminated prepolymer II was subjected to thin-film distillation at 130 ° C. × 0.04 kPa to remove unreacted HDI, thereby obtaining a purified polyisocyanate composition PI-23.
Polyisocyanate composition PI-23 has an NCO content of 16.5% by mass, an external appearance of a transparent liquid, a number average molecular weight of 860, a viscosity at 25 ° C. of 720 mPa · s, and a free HDI content of 0.2% by mass. there were. In addition, the allophanate group content in all linking groups was 47 mol%, the nurate group content was 52 mol%, and the urethane group content was 1 mol%.

<Comparative Example 5>
A 2-liter four-necked flask equipped with a stirrer, thermometer, condenser, and nitrogen gas inlet tube was charged with 880 g of HDI-2 and 120 g of tridecanol, and heated to 85 ° C. with stirring under a nitrogen stream. An isocyanate group-terminated prepolymer I was obtained by performing a urethanization reaction for 3 hours. Thereafter, 0.4 g of tin (II) octylate (divalent / tetravalent = 97/3) was added to the isocyanate group-terminated prepolymer I, and the molar ratio of allophanate group / isocyanurate group was 50/50 at 110 ° C. Allophanate reaction and isocyanurate reaction were carried out until. Thereafter, 0.5 g of JP-508 was added to stop the reaction, and the reaction solution was cooled to room temperature to obtain an isocyanate-terminated prepolymer II. This isocyanate-terminated prepolymer II was subjected to thin-film distillation at 130 ° C. × 0.04 kPa to remove unreacted HDI, thereby obtaining a purified polyisocyanate composition PI-24.
The polyisocyanate composition PI-24 has an NCO content of 16.3% by mass, an appearance that is a transparent liquid, a number average molecular weight of 860, a viscosity at 25 ° C. of 690 mPa · s, and a free HDI content of 0.2% by mass. there were. In addition, the allophanate group content in all linking groups was 52 mol%, the nurate group content was 48 mol%, and the urethane group content was 2 mol%.

<Comparative Example 6>
A 2-liter four-necked flask equipped with a stirrer, thermometer, condenser, and nitrogen gas inlet tube was charged with 880 g of HDI-3 and 120 g of tridecanol, and heated to 85 ° C. with stirring under a nitrogen stream. An isocyanate group-terminated prepolymer I was obtained by performing a urethanization reaction for 3 hours. Thereafter, 0.4 g of tin (II) octylate (divalent / tetravalent = 97/3) was added to the isocyanate group-terminated prepolymer I, and the molar ratio of allophanate group / isocyanurate group was 50/50 at 110 ° C. Allophanate reaction and isocyanurate reaction were carried out until. Thereafter, the reaction did not proceed before the molar ratio of allophanate group / isocyanurate group reached 50/50. Therefore, 0.5 g of JP-508 was added, a stop reaction was performed, the reaction solution was cooled to room temperature, and isocyanate was added. Terminal prepolymer II was obtained. This isocyanate-terminated prepolymer II was thin-film distilled at 130 ° C. × 0.04 kPa to remove unreacted HDI, thereby obtaining a purified polyisocyanate composition PI-25.
The polyisocyanate composition PI-25 has an NCO content of 15.3% by mass, a transparent appearance, a number average molecular weight of 690, a viscosity at 25 ° C. of 350 mPa · s, and a free HDI content of 0.3% by mass. there were. In addition, the allophanate group content in all linking groups was 84 mol%, the nurate group content was 14 mol%, and the urethane group content was 2 mol%.

Tables 2 to 7 show the blending amounts and properties of the raw materials used for the polyisocyanate compositions PI-1 to PI-25.

Abbreviations of the raw materials used in Table 2 are as follows.
(1) HDI-1: hexamethylene diisocyanate (hydrolyzable chlorine content: 221.5 ppm)
(2) Zirconium octylate solution: 50% by weight solid solution of mineral spirit A (3) DABCO TMR: 2-hydroxypropyltrimethylammonium octylate (4) JP-508: acidic phosphate

As shown in Table 3 above, the polyisocyanate compositions according to Examples 1 to 7 are not affected by hydrolyzable chlorine, and the allophanate reaction and isocyanurate reaction proceed efficiently, and the allophanate group And a polyisocyanate composition in which both bonding groups of isocyanurate groups are present in one molecule. This polyisocyanate composition is excellent in storage stability and tolerance.
On the other hand, in the polyisocyanate compositions according to Comparative Examples 1 to 3, the isocyanurate reaction did not proceed due to the influence of hydrolyzable chlorine, and it was difficult to achieve the target composition ratio. Moreover, although the polyisocyanate composition of Comparative Example 4 was able to have a target composition ratio, it became a mixture of the modified allophanate group-containing polyisocyanate and the isocyanurate group-containing polyisocyanate composition, and was stable in storage. It was inferior in tolerance.

The abbreviations of the raw materials used in Table 4 are as follows.
(1) HDI-1: hexamethylene diisocyanate (hydrolyzable chlorine content: 221.5 ppm)
(2) HDI-2: hexamethylene diisocyanate (hydrolyzable chlorine content: 30.0 ppm)
(3) HDI-3: Hexamethylene diisocyanate (hydrolyzable chlorine content: 105.4 ppm)
(4) JP-508: acidic phosphate ester

As shown in Table 5 above, the polyisocyanate compositions according to Example 8, Example 9, Example 11, and Example 12 were not affected by the hydrolyzable chlorine concentration, and were stably allophanatized. The isocyanuration reaction proceeds to obtain a polyisocyanate composition in which both allophanate group and isocyanurate group bonding groups are present in one molecule. This polyisocyanate composition is excellent in storage stability and tolerance. Further, Example 10 having a low tetravalent metal content is affected by a slight hydrolyzable chlorine concentration, but a polyisocyanate composition excellent in storage stability and tolerance can be obtained.
On the other hand, the polyisocyanate composition according to Comparative Example 5 and Comparative Example 6 shows no effect on the reactivity when the hydrolyzable chlorine concentration is low, but the reaction inhibition increases as the concentration increases. As a result, it was difficult to achieve the desired composition ratio. Moreover, although the polyisocyanate composition of Comparative Example 5 was able to have a target composition ratio, a part thereof became a mixture of an allophanate group-containing polyisocyanate composition and an isocyanurate group-containing polyisocyanate composition, It was inferior in tolerance.

The abbreviations of the raw materials used in Table 6 are as follows.
(1) HDI-1: hexamethylene diisocyanate (hydrolyzable chlorine content: 221.5 ppm)
(2) IPA: 2-propanol (3) Calcoal 200GD: 2-octyldodecanol (4) JP-508: acidic phosphate ester

As shown in Table 7 above, the polyisocyanate compositions according to Examples 13 to 19 were excellent in storage stability regardless of the type of alkyl chain of the monoalcohol. Moreover, since the arbitrary allophanate group / isocyanurate group molar ratio was not subject to reaction inhibition, it was easy to adjust.

<Synthesis of extensible paint curing agent>
<Example 20>
Polyisocyanate composition PI-2 prepared in Example 2 (NCO content: 16.4% by mass) in a two-liter four-necked flask equipped with a stirrer, thermometer, cooling pipe, and nitrogen gas introduction pipe And 495 g of Exenol 1020 (number average molecular weight: 1000, terminal EO-added polypropylene glycol, manufactured by Asahi Glass Co., Ltd.), heated to 85 ° C. with stirring in a nitrogen stream, and subjected to urethanization reaction for 3 hours A hardener for extensible paint HD-1 having a content of 4.1% by mass was obtained.

<Comparative Example 7>
Polyisocyanate composition PI-21 prepared in Comparative Example 2 (NCO content: 14.8% by mass) in a two-liter four-necked flask equipped with a stirrer, thermometer, cooling pipe, and nitrogen gas introduction pipe And 468 g of Exenol 1020 (number average molecular weight: 1000, terminal EO-added polypropylene glycol, manufactured by Asahi Glass Co., Ltd.), heated to 85 ° C. with stirring under a nitrogen stream, and subjected to urethanization reaction for 3 hours. A curing agent HD-2 for paint having a content of 3.7% by mass was obtained.

<Comparative Example 8>
Polyisocyanate composition PI-23 prepared in Comparative Example 4 (NCO content: 16.5% by mass) was added to a 2-liter four-necked flask equipped with a stirrer, thermometer, cooling pipe, and nitrogen gas introduction pipe. And 495 g of Exenol 1020 (number average molecular weight: 1000, terminal EO-added polypropylene glycol, manufactured by Asahi Glass Co., Ltd.), heated to 85 ° C. with stirring under a nitrogen stream, and subjected to urethanization reaction for 3 hours. A curing agent HD-3 for paint having a content of 4.1% by mass was obtained.

<Adjustment of two-component paint>
As shown in Table 8, the compounding amount was obtained by using R (isocyanate group / (Mole ratio of hydroxyl group) = 1, and titanium oxide (trade name: CR-90, crystal structure: rutile type, manufactured by Ishihara Sangyo Co., Ltd.) and organic solvent [(E), mineral spirit A , Manufactured by JX Nippon Oil & Energy Co., Ltd.] so as to have a solid content of 50%, and stirred at 300 rpm for 3 minutes using a homomixer to prepare a two-component paint.

<Coating method and test piece adjustment>
Using the applicator on a steel plate (JIS G3141, trade name: SPCC-SB, presence / absence of treatment: PF-1077, manufactured by Nippon Test Panel Industry Co.) It applied so that it might become. Thereafter, heat treatment was carried out in a dryer at a temperature of 60 ° C. for 1 hour, followed by curing for 7 days in an environment at a temperature of 23 ° C. and a relative humidity of 50% to obtain a coating film.

Abbreviations of raw materials used in Table 8 are as follows.
(1) Acrydic HU-596: acrylic polyol (hydroxyl value: 30 mg KOH / g)
(2) CR-90: Titanium oxide

As shown in Table 9 above, the two-component paint according to Example 20 was excellent in extensibility such as cupping resistance and elongation, and further excellent in weather resistance.
On the other hand, the two-component paint according to Comparative Example 7 is inferior in pencil hardness and weather resistance, and the two-component paint according to Comparative Example 8 is inferior in extensibility such as cupping resistance and elongation. .

(1) Evaluation test 1:
<Storage stability>
The obtained polyisocyanate composition was allowed to stand at −10 ° C. and 25 ° C. for 168 hours, and the presence or absence of turbidity, suspended matter and precipitate was visually evaluated.

<Evaluation criteria>
・ No turbidity, suspended matter, or precipitate is observed: Pass (Evaluation: ○)
・ Muddyness is recognized: Pass (Evaluation: △)
-Precipitates are observed: reject (evaluation: x)

(2) Evaluation test 2:
<Tolerance>
1 g each of the obtained polyisocyanate composition was sampled, and HAWS (shell chemicals), mineral spirit A (manufactured by JX Nippon Mining & Energy Corporation), and IP solvent 2028 (manufactured by Idemitsu Kosan Co., Ltd.) having different aniline points were added to each. Then, the titer that caused turbidity was calculated as the end point.

<Calculation formula>
T = L / S
・ T: Tolerance (times)
L: titration amount of organic solvent (g)
S: Sample amount (g)

(3) Evaluation test 3:
<Glossiness>
The coating film obtained in Example 20, Comparative Example 7 and Comparative Example 8 was measured for glossiness at 60 ° with a haze-gloss reflectometer according to JIS Z8741.

<Evaluation criteria>
・ 80% or more: Pass (Evaluation: ○)
-60% or more and less than 80: Pass (Evaluation: Δ)
-Less than 60%: Fail (Evaluation: x)

(4) Evaluation test 4:
<Pencil hardness>
In accordance with JIS K5600-5-4: 1999, the hardness of a pencil that could not be torn was measured.

(5) Evaluation test 5:
<Flexibility>
Using a cylindrical mandrel with a diameter of 2 mm according to JIS K5600-5-1: 1999 flex resistance test, evaluating the presence or absence of film cracking and peeling from the steel sheet when bent by the cylindrical mandrel did.

<Evaluation criteria>
・ No cracking or peeling of coating film: Pass (Evaluation: ○)
-Cracking and peeling of the coating film have occurred: Fail (Evaluation: x)

(6) Evaluation test 6:
<Copping resistance>
According to the cupping resistance test of JIS K5600-5-2: 1999, the indentation depth (mm) until peeling from the steel sheet was measured after cracking of the coating film when subjected to partial deformation by indentation.

(7) Evaluation test 7:
<Weight drop resistance>
According to JIS K5600-5-3: 1999 bending resistance test, use a weight of 10.3 mm in diameter and 0.5 kg in mass, and set the minimum drop height (cm) at which the coating film will crack and peel off. It was measured.

(8) Evaluation test 8:
<Adhesion>
According to a cross cut tape peeling test of JIS K5600-5-6: 1999, a 1 mm square cross cut (10 × 10) was cut in the coating film, and a tape peel test was performed to measure the number of remaining sheets.

(9) Evaluation test 9:
<Weather resistance>
The coating film obtained in Example 20, Comparative Example 7 and Comparative Example 8 was subjected to an accelerated weather resistance test under the following conditions.
・ Test equipment: QUV (manufactured by Q-LAB)
・ Lamp: EL-313
Illuminance: 0.59 w / m ²
・ Λmax: 313 nm
1 cycle: 12 hours [UV irradiation: 8 hours (temperature 70 ° C.), condensation: 4 hours (temperature 50 ° C.)]
・ Test time: 964 hours

<Evaluation criteria>
According to JIS Z8741, the glossiness at 60 ° was measured with a haze-gloss reflectometer, and the gloss retention was calculated. The gloss retention was determined by the following formula.
Gloss retention (%) = 100 × Glossiness after weathering test ÷ Initial glossiness / 80% or more: Pass (Evaluation: ○)
・ 70% to less than 80%: Pass (Evaluation: △)
-Less than 70%: Fail (Evaluation: x)

(10) Evaluation test 10:
<Recoatability>
An adherend was prepared by forming 50 μm of the two-component paint of Example 20 (Acridic HU-596 / Extensible paint curing agent HD-1) on a steel plate. The adjusted two-component paint was applied to the upper layer of the adherend so as to have a film thickness of 50 μm, and the swelling of the coating film and the presence or absence of wrinkles were visually confirmed.

<Evaluation criteria>
・ No change in appearance of coating film: Pass (Evaluation: ○)
・ Swelling and wrinkle of the coating film are generated: reject (evaluation: x)

(11) Evaluation test 11:
<Tensile properties>
The two-component paint obtained in Example 20, Comparative Example 7 and Comparative Example 8 was applied on a release paper so that the dry coating film became 150 μm, and dried at 80 ° C. for 2 hours, and then a coating film was formed. did. Then, the test piece was produced with the dumbbell cutter, and the tensile physical property was evaluated at a tensile speed of 200 mm / min.

<Evaluation criteria>
・ Elongation at break is 150% or more: Pass (Evaluation: ○)
-Elongation at break is less than 150%: Fail (Evaluation: x)

Claims (9)

An allophanate isocyanurate-forming catalyst (A) comprising a structural unit represented by the general formula (1).

(M in the general formula (1) represents a tetravalent metal selected from tin, zirconium and zinc. R represents a bonding group selected from an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group and a phenyl group. Show.) The allophanate isocyanurate catalyst (A) according to claim 1, wherein the allophanate isocyanurate catalyst (A) is a compound represented by the general formula (2).

(M in the general formula (2) represents a tetravalent metal selected from tin, zirconium, and zinc. R represents a bonding group selected from an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group, and a phenyl group. The polymerization degree n is an integer of 2 to 100.) The allophanate isocyanurate-forming catalyst (A) according to claim 1, wherein the allophanate-isocyanurate-forming catalyst (A) is a compound represented by the general formula (3).

(M in the general formula (3) represents a tetravalent metal selected from tin, zirconium and zinc. R represents a bonding group selected from an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group and a phenyl group. The polymerization degree n is an integer of 2 to 100.) The tetravalent metal content of the allophanate / isocyanurate-forming catalyst (A) is at least 10% by mass with respect to the total metal content. Allophanate-isocyanurate catalyst (A). The allophanate / isocyanurate catalyst (A) is obtained by oxidizing the carboxylic acid metal salt represented by at least one general formula (4) to general formula (6). 5. The method for producing an allophanate isocyanurate catalyst according to any one of 4 above.

(M in the general formulas (4) to (6) represents a divalent metal selected from tin, zirconium, and zinc. R represents an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group, and a phenyl group. A linking group selected from the above. A polyisocyanate composition obtained from a reaction of an organic diisocyanate (B) and a monoalcohol (C) in the presence of the allophanate isocyanurate-forming catalyst (A) according to any one of claims 1 to 5. A thing,
The organic diisocyanate (B) is an aliphatic diisocyanate or an alicyclic diisocyanate,
The monoalcohol (C) contains an alkyl group having 1 to 20 carbon atoms,
Allophanate groups and isocyanurate groups in the polyisocyanate composition are characterized by containing allophanate groups / isocyanurate groups = 80/20 to 30/70 in a molar ratio. It is a manufacturing method of the polyisocyanate composition of Claim 6, Comprising:
First step: A step of producing an isocyanate group-terminated prepolymer I by subjecting an organic diisocyanate (B) and a monoalcohol (C) to a urethanization reaction,
Second step: Using the isocyanate group-terminated prepolymer I and the allophanate / isocyanurate catalyst (A) to produce an isocyanate group-terminated prepolymer II by an allophanate reaction and an isocyanurate reaction,
Third step: a step of stopping the reaction of the isocyanate group-terminated prepolymer II with a reaction stopper,
Fourth step: a step of removing the content of free organic diisocyanate (B) by thin film distillation or solvent extraction until the content is less than 1% by mass;
The method of manufacturing a polyisocyanate composition by this. A curing agent for an extensible paint obtained by reacting the polyisocyanate composition according to any one of claims 6 and 7 with a polyol (D). The extensible paint for an extensible paint according to claim 8, comprising an organic solvent (E) having an aniline point according to JIS K 2256 or a mixed aniline point of 5 to 100 ° C. Curing agent.