JP2017048270A - Polyisocyanate composition and method for producing the same - Google Patents

Abstract

Disclosed is a polyisocyanate composition which has a small change in viscosity before and after storage and a small change in the content of isocyanate groups, and is excellent in curability and sagging when used as a paint. A polyisocyanate obtained from one or more selected from the group consisting of an aliphatic diisocyanate and an alicyclic diisocyanate and a polyvalent hydroxy compound having a hydroxyl group average functional group number of 4.0 or more and 10 or less; A polyisocyanate composition having a specific structure, wherein the polyisocyanate composition is based on the total amount of the polyisocyanate composition. Is a polyisocyanate composition containing 10 mass ppm or more and 10000 mass ppm or less and having predetermined various physical properties. [Selection figure] None

Description

  The present invention relates to a polyisocyanate composition and a method for producing the same.

  Using at least one diisocyanate selected from aliphatic diisocyanate and alicyclic diisocyanate and a polyol compound having an average number of hydroxyl groups of 2.0 or more, having a urethane group or an allophanate group in its structure, Polyisocyanates having no isocyanurate groups are known (for example, Patent Documents 1 to 3). This polyisocyanate is excellent in weather resistance and heat resistance as compared with a polyisocyanate using an aromatic diisocyanate instead of the above diisocyanate as a raw material. Compared to polyisocyanates having substantially isocyanurate groups, it is less necessary to use a catalyst at the time of production, and various performances are manifested by selecting the type of raw material polyol compound, so it is widely used. ing.

  In addition, a technique has been proposed in which a polyisocyanate having a low yellowing degree can be obtained at the time of production of a polyisocyanate or by adding a phosphite compound to the produced polyisocyanate (for example, Patent Documents 4 and 5). ).

JP-A 61-28518 Japanese Patent Publication No. 63-37125 JP-A-8-325516 JP 59-98050 A JP 63-96178 A

  However, when the polyisocyanate disclosed in Patent Documents 1 to 3 is stored, depending on the storage conditions, the viscosity of the polyisocyanate after storage may be increased, the content of the isocyanate group may be decreased, and the like.

  Moreover, the polyisocyanate proposed by patent documents 4 and 5 has the further subject about sclerosis | hardenability and sagging property at the time of using it as a coating material. For this reason, no investigation has been made on the change in viscosity and the change in the content of isocyanate groups when the polyisocyanate is stored.

  Then, an object of this invention is to provide the polyisocyanate composition which is excellent in sclerosis | hardenability and sagging property at the time of using as a coating material with the change of the viscosity before and behind storage, and the change of the content rate of an isocyanate group being small.

  As a result of earnest research to solve the above-mentioned problems of the prior art, the present inventor has found that a polyisocyanate having an aliphatic diisocyanate unit and / or an alicyclic diisocyanate unit having specific properties, phosphorous acid having a predetermined range and a specific structure. A polyisocyanate composition containing a triester compound and having specific physical properties has little change in viscosity before and after storage and little change in isocyanate group content, and is excellent in curability and sagging when used as a paint. The present invention has been discovered.

That is, the present invention is as follows.
[1]
A polyisocyanate obtained from one or more selected from the group consisting of an aliphatic diisocyanate and an alicyclic diisocyanate, and a polyvalent hydroxy compound having a hydroxyl group average functional group number of 4.0 or more and 10 or less;
A polyisocyanate composition containing a phosphorous acid triester compound represented by the following formula (I):
The polyisocyanate composition contains 10 mass ppm or more and 10000 mass ppm or less of the phosphorous acid triester compound with respect to the total amount of the polyisocyanate composition, and satisfies all of the following (1) to (4). Isocyanate composition.
P (OR ₁ ) (OR ₂ ) (OR ₃ ) (I)
(In formula (I), R ₁ , R ₂ , and R ₃ each independently represents a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms, or an aryl group.)
(1) Isocyanate average functional group number is 4.0 or more and 20 or less (2) Isocyanate concentration is 5.0% by mass or more and 20% by weight or less (3) Viscosity is 2000 mPa · s / 25 ° C. or more and 200,000 mPa.s. s / 25 ° C. or less (4) Isocyanate cyclic trimer concentration is 10% by mass or less [2]
The polyisocyanate composition according to [1], wherein the polyisocyanate has an allophanate bond and a urethane bond in its structure.
[3]
The polyisocyanate composition according to [1] or [2], wherein the polyvalent hydroxy compound is one or more selected from the group consisting of a propylene oxide adduct polyether polyol and a polyester polyol.
[4]
A polyisocyanate is obtained by reacting one or more selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates with a polyvalent hydroxy compound having a hydroxyl group average functional group number of 4.0 or more and 10 or less. A reaction process;
Mixing the polyisocyanate and a phosphorous acid triester compound represented by the following formula (I) to obtain a polyisocyanate composition,
The polyisocyanate composition contains 10 mass ppm or more and 10000 mass ppm or less of the phosphorous acid triester compound with respect to the total amount of the polyisocyanate composition, and satisfies all of the following (1) to (4). A method for producing a polyisocyanate composition.
P (OR ₁ ) (OR ₂ ) (OR ₃ ) (I)
(In formula (I), R ₁ , R ₂ , and R ₃ each independently represents a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms, or an aryl group.)
(1) Isocyanate average functional group number is 4.0 or more and 20 or less (2) Isocyanate concentration is 5.0% by mass or more and 20% by weight or less (3) Viscosity is 2000 mPa · s / 25 ° C. or more and 200,000 mPa.s. s / 25 ° C. or less (4) Isocyanate cyclic trimer concentration is 10% by mass or less

  According to the polyisocyanate composition according to the present invention, the change in viscosity before and after storage and the change in the content of isocyanate groups are small, and when used as a paint, the curability and sagging properties are excellent.

  Hereinafter, a mode for carrying out the present invention (hereinafter simply referred to as “the present embodiment”) will be described in detail. The following embodiments are examples for explaining the present invention, and are not intended to limit the present invention to the following contents. The present invention can be implemented with appropriate modifications within the scope of the gist thereof. Unless otherwise specified, “(meth) acryl” includes methacryl and acryl, and “(meth) acrylate” includes methacrylate and acrylate. In addition, the content of isocyanate groups is hereinafter also referred to as “NCO content” or “isocyanate group concentration”.

[Polyisocyanate composition]
The polyisocyanate composition of the present embodiment is a polyhydric hydroxy compound having one or more selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates and having a hydroxyl group average functional group number of 4.0 or more and 10 or less And a phosphorous acid triester compound represented by the following formula (I).
P (OR ₁ ) (OR ₂ ) (OR ₃ ) (I)
In the formula (I), R ₁ , R ₂ , and R ₃ each independently represents a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms, or an aryl group.
Moreover, the polyisocyanate composition of this embodiment contains 10 mass ppm or more and 10000 mass ppm or less of the said phosphorous acid triester compound with respect to the total amount of this polyisocyanate composition, and following (1)-(4 ) Are all satisfied.
(1) Isocyanate average functional group number is 4.0 or more and 20 or less (2) Isocyanate concentration is 5.0 mass% or more and 20 mass% or less (3) Viscosity is 2000 mPa · s / 25 ° C. or more and 200,000 mPa.s. s / 25 ° C. or less (4) Isocyanate cyclic trimer concentration is 10% by mass or less

[Polyisocyanate]
The polyisocyanate of this embodiment is obtained using a diisocyanate of an aliphatic diisocyanate and / or an alicyclic diisocyanate and a specific polyol compound as raw materials.

  The polyisocyanate preferably has a urethane bond and an allophanate bond in its structure. The allophanate bond of the polyisocyanate bond is more preferably from 10 mol% to 90 mol%, and still more preferably from 20 mol% to 80 mol%, based on the total amount of urethane bonds and allophanate bonds. When the allophanate bond is 10 mol% or more, the polyisocyanate composition tends to have a larger number of isocyanate average functional groups and the viscosity does not become too high. Further, when the allophanate bond is 90 mol% or less, mechanical properties such as toughness, which is an excellent physical property of the urethane bond, are easily exhibited, and heat resistance tends to be obtained. In order to obtain a polyisocyanate having an allophanate bond in the above range, for example, the type and amount of a catalyst described later may be adjusted. Allophanate binding can be quantified by nuclear magnetic resonance (NMR).

<Diisocyanate>
Although it does not specifically limit as said aliphatic diisocyanate, A C4-C30 aliphatic diisocyanate is preferable. The aliphatic diisocyanate having 4 to 30 carbon atoms is not particularly limited. For example, 1,4-diisocyanatobutane, 1,5-diisocyanatopentane, 1,6-diisocyanatohexane (hereinafter referred to as “HDI”). And 2,2,4-trimethyl-1,6-diisocyanatohexane, lysine diisocyanate. Among these, HDI is more preferable from the viewpoint of industrial availability. Aliphatic diisocyanates may be used alone or in combination of two or more.

  Although it does not specifically limit as said alicyclic diisocyanate, C8-C30 alicyclic diisocyanate is preferable. The alicyclic diisocyanate having 8 to 30 carbon atoms is not particularly limited. For example, isophorone diisocyanate (hereinafter abbreviated as “IPDI”), 1,3-bis (isocyanatomethyl) -cyclohexane, 4,4 ′ -Dicyclohexylmethane diisocyanate, norbornene diisocyanate, hydrogenated xylylene diisocyanate. Among these, IPDI is more preferable from the viewpoint of weather resistance and industrial availability. An alicyclic diisocyanate may be used independently and may use 2 or more types together.

  Among these diisocyanates, HDI is more preferable from the viewpoint of industrial availability and reactivity during the production of polyisocyanate.

<Polyvalent hydroxy compound>
The polyvalent hydroxy compound of this embodiment has a hydroxyl group average functional group number of 4.0 or more and 10 or less, preferably 4.0 or more and 8.0 or less. The hydroxyl group average functional group number is the number of hydroxyl groups that one molecule of the polyvalent hydroxy compound has statistically. In particular, when the polyvalent hydroxy compound is a polymer, the number average molecular weight of the polyvalent hydroxy compound and the total number of hydroxyl groups contained in 1.0 part by mass of the polyvalent hydroxy compound (hereinafter referred to as “hydroxyl concentration”) It is calculated by the general formula (1).

  Specific examples of the polyvalent hydroxy compound include, but are not limited to, for example, diglycerin, ditrimethylolpropane, pentaerythritol, dipentaerythritol, etc., for example, erythritol, D-threitol, L-arabinitol, ribitol, xylitol, Sugar alcohol compounds such as sorbitol, glycidol, mannitol, galactitol, rhamnitol; monosaccharides such as arabinose, ribose, xylose, glucose, mannose, galactose, fructose, sorbose, rhamnose, fucose, ribosese; trehalose, sucrose, maltose, Disaccharides such as cellobiose, gentiobiose, lactose and melibiose; trisaccharides such as raffinose, gentianose and meletitose; tetrasaccharides such as stachyose And the like.

  In addition to the polyvalent hydroxy compounds other than the polyvalent hydroxy compounds of the specific examples described above, polyether polyols, polyester polyols, and polyols of epoxy polyols using the polyvalent hydroxy compounds of the specific examples described above as raw materials are also included. .

  The polyether polyols are not particularly limited, but in the presence of a strongly basic catalyst such as a hydroxide, an alcoholate, an alkylamine, or the like, such as a hydroxide such as lithium, sodium, or potassium; Polyether polyols obtained by adding a single or mixture of alkylene oxides such as ethylene oxide, propylene oxide, butylene oxide, cyclohexene oxide, styrene oxide, etc., obtained by reacting a polyfunctional compound such as ethylenediamine with alkylene oxide. Polyether polyols obtained, and so-called polymer polyols obtained by polymerizing acrylamide or the like using these polyethers as a medium.

  Polyester polyols are not particularly limited, but at least one selected from the group consisting of carboxylic acids such as succinic acid, adipic acid, sebacic acid, dimer acid, maleic anhydride, phthalic anhydride, isophthalic acid, terephthalic acid and the like. Polyester polyol resins obtained by a condensation reaction between a dibasic acid and at least one polyhydric alcohol selected from the group consisting of ethylene glycol, propylene glycol, diethylene glycol, neopentyl glycol, trimethylolpropane and glycerin, and the above-mentioned It is possible to obtain polycaprolactone polyols obtained by ring-opening polymerization addition of ε-caprolactone to the polyvalent hydroxy compound of the specific examples.

  Epoxy polyols are not particularly limited. For example, novolak type, β-methyl epichloro type, cyclic oxirane type, glycidyl ether type, glycol ether type, aliphatic unsaturated compound epoxy type, epoxidized fatty acid ester type, polyvalent type Examples include carboxylic acid ester type, aminoglycidyl type, halogenated type, and resorcin type epoxy polyols.

  Among these polyols, preferred are the above polyether polyols and the above polyester polyols, more preferred are polyether polyols, and further preferred are propylene oxide adduct polyether polyols. Moreover, it is preferable that a polyhydric hydroxy compound is 1 type, or 2 or more types selected from the group which consists of a propylene oxide adduct polyether polyol and a polyester polyol.

  The number average molecular weight of the polyol described above is preferably 500 or more and 5000 or less, and more preferably 600 or more and 3000 or less. A number average molecular weight is calculated | required by measuring according to the gel permeation chromatograph measurement as described in the Example mentioned later.

  These polyvalent hydroxy compounds may be used alone, in combination of two or more, or may be modified with urethane or the like.

[Phosphorous acid triester compound]
In the polyisocyanate composition of the present embodiment, the phosphorous acid triester compound represented by the following formula (I) is added to the total amount of the polyisocyanate composition from the viewpoint of reducing the viscosity change before and after storage and the NCO content change reduction. On the other hand, it contains 10 mass ppm or more and 10000 mass ppm or less.
P (OR ₁ ) (OR ₂ ) (OR ₃ ) (I)
In the formula (I), R ₁ , R ₂ , and R ₃ each independently represents a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms, or an aryl group. By containing a phosphorous acid triester compound in the said range, the viscosity change before and behind storage, NCO content rate change, and chromaticity change can be reduced.

  The content of the phosphorous acid triester compound is preferably 20 ppm by mass or more, more preferably 30 ppm by mass or more, still more preferably 40 ppm by mass or more, and preferably 9000 ppm by mass or less. More preferably, it is 8500 mass ppm or less, More preferably, it is 8000 mass ppm or less.

R ₁ , R ₂ , and R ₃ in the formula (I) each independently represent an alkyl group or an aryl group having a linear, branched, or cyclic structure having 1 to 20 carbon atoms. Specific examples of R ₁ , R ₂ , and R ₃ are not particularly limited, but include, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, n- Examples include pentyl group, n-hexyl group, cyclohexyl group, 2-ethylhexyl group, phenyl group, cresyl group, xylyl group, ethylphenyl group, isopropylphenyl group, and benzyl group. The upper limit value of the carbon number of R ₁ , R ₂ , and R ₃ is 20 from the viewpoint of independently reducing chromaticity change, viscosity change, and molecular weight change before and after storage, and is preferably 18. R ₁ , R ₂ , and R ₃ are each independently, preferably a combination that is all linear or branched, or a combination of a linear or branched and a cyclic one, before and after storage. This is preferable from the viewpoint of suppressing a change in chromaticity.

  Specific examples of the phosphorous acid triester compound are not particularly limited. For example, triphenyl phosphite, trisnonylphenyl phosphite, tricresyl phosphite, triethyl phosphite, tris (2-ethylhexyl) phosphite, Tridecyl phosphite, trilauryl phosphite, tris (tridecyl) phosphite, trioleyl phosphite, diphenyl mono (2-ethylhexyl) phosphite, diphenyl monodecyl phosphite, diphenyl mono (tridecyl) phosphite, trilauryl trithiophos Phyto, diethyl hydrogen phosphite, bis (2-ethylhexyl) hydrogen phosphite, dilauryl hydrogen phosphite, dilauryl hydrogen phosphite, dioleyl Idrogen phosphite, diphenyl hydrogen phosphite, tetraphenyl dipropylene glycol diphosphite, tetra (C12-C15 alkyl) 4,4 isopropylidene diphenyl diphosphite, bis (decyl) pentaerythritol diphosphite, bis (tridecyl) Pentaerythritol diphosphite, tristearyl phosphite, distearyl pentaerythritol diphosphite, tris (2,4-di-tbutylphenyl) phosphite, 6- [3- (3-t-butyl-4-hydroxy-5) -Methylphenyl) propoxy] -2,4,8,10-tetra-t-butyldibenz [d, f] [1,3,2] zodioxaphosphine, methylenebis (di-t-butylphenyl) octylphos Fight, SUMILI ER-GP (trade name manufactured by Sumitomo Chemical Co., Ltd.), ADK STAB HP10, ADK STAB PEP-8, ADK STAB PEP-36 / 36A, ADK STAB HP1500, ADK STAB TPP (trade names manufactured by ADEKA), JP333E (products manufactured by Johoku Chemical Co., Ltd.) Name), IRGAFOS 168 (trade name, manufactured by BASF). These may be used individually by 1 type and may use 2 or more types together.

  The polyisocyanate composition of the present embodiment has an isocyanate average functional group number of 4.0 or more and 20 or less, preferably 5.0 or more and 14 or less, more preferably 6.0 or more and 12 or less. When the isocyanate average functional group number is 4.0 or more, sufficient curability can be obtained when the polyisocyanate composition is used in a coating composition, and the isocyanate average functional group number is 20 or less. When the product is used in a coating composition, a good coating surface property can be obtained.

In the polyisocyanate composition of this embodiment, the number of isocyanate average functional groups is the number of isocyanate functional groups statistically possessed by one molecule of polyisocyanate, the number average molecular weight of the polyisocyanate composition described later, and polyisocyanate 1 described later. It is calculated by the following general formula (2) from the isocyanate concentration contained in 0.0 part by mass.

  The polyisocyanate composition of this embodiment has an NCO content (isocyanate concentration) of 5.0% by mass or more and 20% by mass or less. When the NCO content is 5.0% by mass or more, a polyisocyanate composition having a sufficient crosslinking density is obtained. Moreover, it is suppressed that the crosslinking density of a polyisocyanate composition becomes high too much because NCO content rate is 20 mass% or less. The NCO content can be measured by the method described in Examples described later.

  The polyisocyanate composition of the present embodiment has a viscosity of 2,000 mPa · s / 25 ° C. to 200,000 mPa · s / 25 ° C., preferably 5,000 mPa · s / 25 ° C. to 100,000 mPa · s /. It is 25 degrees C or less. When the viscosity is 2,000 mPa · s / 25 ° C. or more, sagging at the time of painting with respect to the vertical surface when the polyisocyanate composition is used for the coating composition is prevented, and the viscosity is 200,000 mPa · s / 25 ° C. or less. As a result, a good coating appearance can be obtained when the polyisocyanate composition is used in a coating composition. A viscosity can be measured by the method as described in the Example mentioned later.

  The polyisocyanate composition of the present embodiment has an isocyanate cyclic trimer concentration of 10% by mass or less. When the isocyanate cyclic trimer concentration is 10% by mass or less, the decrease in the number of isocyanate average functional groups is suppressed. In addition, when this isocyanate cyclic trimer is baked at a low temperature and in a short time, the coating composition The possibility of elution into a solvent or the like can be suppressed.

  The isocyanate cyclic trimer concentration can be determined by the area percentage of the isocyanate cyclic trimer peak obtained by gel permeation chromatography using tetrahydrofuran as a carrier and the refractive index as a detector. Specifically, it can measure by the method as described in the Example mentioned later.

  In the polyisocyanate composition of the present embodiment, the allophanate bond concentration is preferably 10 mol% or more and 90 mol% or less, more preferably 20 mol% or more and 80 mol% or less. When the allophanate bond concentration is 10 mol% or more, the polyisocyanate composition tends to have a larger number of isocyanate average functional groups and the viscosity does not become too high, and the allophanate bond concentration is 90 mol% or less. Mechanical properties such as toughness, which is an excellent physical property of the bond, are easily exhibited, and heat resistance tends to be obtained. In order to obtain a polyisocyanate composition having an allophanate bond concentration in such a range, the type and amount of the catalyst described later may be adjusted. The allophanate binding concentration can be determined by the method described in Examples described later.

  The polyisocyanate composition of the present embodiment is stored at 50 ° C. for 30 days, and the increase in coloring degree after storage is preferably less than 75, more preferably less than 50. By making the increase in the coloring degree less than 75, the coloring degree of the coating film of the coating composition can be obtained without any problem. In order to obtain a polyisocyanate composition having an increase in coloring degree in such a range, a phosphite compound described later may be used. The degree of coloring can be determined by the method described in Examples described later.

[Method for producing polyisocyanate composition]
The manufacturing method of the polyisocyanate composition of this embodiment has a reaction process and a mixing process. The reaction step comprises reacting one or more selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates with a polyvalent hydroxy compound having a hydroxyl group average functional group number of 4.0 or more and 10 or less. Isocyanate is obtained.
Moreover, a mixing process mixes the said polyisocyanate and the phosphorous acid triester compound represented by following formula (I), and obtains a polyisocyanate composition. Here, the obtained polyisocyanate composition contains 10 mass ppm or more and 10000 mass ppm or less of the phosphorous acid triester compound with respect to the total amount of the polyisocyanate composition, and the following (1) to (4 ) Are all satisfied.
P (OR ₁ ) (OR ₂ ) (OR ₃ ) (I)
In the formula (I), R ₁ , R ₂ , and R ₃ each independently represents a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms, or an aryl group.
(1) Isocyanate average functional group number is 4.0 or more and 20 or less (2) Isocyanate concentration is 5.0% by mass or more and 20% by weight or less (3) Viscosity is 2000 mPa · s / 25 ° C. or more and 200,000 mPa.s. s / 25 ° C. or less (4) Isocyanate cyclic trimer concentration is 10% by mass or less

[Reaction process]
The reaction process of this embodiment comprises one or more selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates, and a polyhydroxy compound having a hydroxyl group average functional group number of 4.0 or more and 10 or less. If it is the process of making it react and obtaining the polyisocyanate mentioned above, it will not specifically limit.

  Since the reaction solution after the reaction step often contains unreacted HDI monomer, it is preferable to remove this by a treatment such as thin film evaporation and extraction. By performing such treatment, it is preferable to control the concentration of the HDI monomer contained in the polyisocyanate composition to 1.0% by mass or less. The HDI monomer concentration is more preferably 0.7% by mass or less, further preferably 0.5% by mass or less, still more preferably 0.3% by mass or less, and still more preferably 0.1% by mass. % Or less. By setting the HDI monomer concentration to 1.0% by mass or less, the toxicity of the polyisocyanate composition can be further suppressed, and the safety tends to be improved. The HDI monomer concentration can be determined by the method described in Examples described later.

  The yield in the reaction step is preferably 20% by mass or more and 70% by mass or less. It is preferable to remove the unreacted diisocyanate and the solvent after the reaction step or after the mixing step described later.

  In the case of reacting the polyvalent hydroxy compound and diisocyanate, the equivalent ratio of isocyanate group / hydroxyl group is preferably 2/1 or more and 30/1 or less, more preferably 5/1 or more and 20/1 or less. By setting the equivalent ratio to 2/1 or higher, the viscosity of the reaction solution after the reaction does not become too high, and the equipment investment in industrial production tends to be small, and the equivalent ratio is set to 30/1 or lower. Therefore, it tends to be possible to suppress the decrease in productivity. The polyvalent hydroxy compound and the diisocyanate may be mixed before raising the temperature of the reaction solution, or the diisocyanate is charged into the reactor first, and after reaching the predetermined temperature, the polyvalent hydroxy compound is added all at once or in divided portions. May be.

  In the reaction step, a solvent can also be used. In that case, the solvent is preferably a solvent inert to the isocyanate group.

  The reaction temperature is preferably 60 ° C. or higher and 200 ° C. or lower, more preferably 130 ° C. or higher and 180 ° C. or lower. By setting the reaction temperature to 60 ° C. or higher, the reaction rate does not slow, and an increase in the average number of isocyanate average functional groups estimated to be due to the allophanatization reaction tends to be obtained. By making reaction temperature 200 degrees C or less, it exists in the tendency for coloring of the obtained polyisocyanate to become small. Although reaction time changes with reaction temperature, 1.0 hour or more and 8.0 hours or less are preferable, More preferably, they are 2.0 hours or more and 6.0 hours or less.

  A catalyst can also be used in the reaction step. As the catalyst, those having basicity are preferable. Although it does not specifically limit as what has basicity, For example, Tetraalkylammonium hydroxide; Quaternary amine compounds, such as organic weak acid salts, such as an acetic acid and a capric acid; Trioctylamine, 1, 4- diazabicyclo (2, 2,2) tertiary amine compounds such as octane, 1,8-diazabicyclo (5,4,0) undecene-7, 1,5-diazabicyclo (4,3,0) nonene-5; acetylacetone metal such as zinc Examples thereof include catalysts that promote the allophanatization reaction of metal organic weak acid salts such as salts, zinc, tin, lead, and iron.

  In the case of using a catalyst, the content of the catalyst is preferably 0.001% by mass or more and 1.0% by mass or less with respect to the total amount (100% by mass) of the diisocyanate compound. It is preferable that a part of the urethane bond present in the reaction solution is converted to an allophanate bond. That is, the obtained polyisocyanate preferably has a urethane bond and an allophanate bond in its structure. The conversion of urethane bonds to allophanate bonds is preferably 10 mol% or more and 90 mol% or less, more preferably 20 mol% or more and 80 mol% or less. When the conversion is 10 mol% or more, an increase in the number of isocyanate average functional groups of the polyisocyanate composition is obtained, and the viscosity tends not to be too high. When the conversion is 90 mol% or less, mechanical properties such as toughness, which is an excellent physical property of the urethane bond, are easily exhibited, and heat resistance tends to be obtained.

[Mixing process]
The mixing process of this embodiment will not be specifically limited if it is the process of mixing the polyisocyanate mentioned above and the phosphorous acid triester compound represented by following formula (I), and obtaining a polyisocyanate composition. Here, the obtained polyisocyanate composition contains 10 mass ppm or more and 10000 mass ppm or less of the phosphorous acid triester compound with respect to the total amount of the polyisocyanate composition, and the following (1) to (4 ) Are all satisfied.
P (OR ₁ ) (OR ₂ ) (OR ₃ ) (I)
In the formula (I), R ₁ , R ₂ , and R ₃ each independently represents a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms, or an aryl group.
(1) Isocyanate average functional group number is 4.0 or more and 20 or less (2) Isocyanate concentration is 5.0% by mass or more and 20% by weight or less (3) Viscosity is 2000 mPa · s / 25 ° C. or more and 200,000 mPa.s. s / 25 ° C. or less (4) Isocyanate cyclic trimer concentration is 10% by mass or less

  The mixing process of this embodiment should just finally mix the polyisocyanate and phosphite triester compound in a reaction process, and may add a phosphite triester compound with respect to diisocyanate before a reaction process. And a phosphorous acid triester compound may be added with respect to the reaction liquid after a reaction process, and a phosphorous acid triester compound may be added between reaction processes. Further, after removing the HDI monomer, a phosphorous acid triester compound may be added to the polyisocyanate.

[Coating composition]
The coating composition or coating composition of the present embodiment contains the polyisocyanate composition of the present embodiment as their curing agent. The coating composition contains a resin component as a main ingredient. Although the coating composition is not particularly limited, for example, a resin containing a compound having two or more active hydrogens in the molecule as a resin component or a solvent dilution thereof, if necessary, other resins, catalysts, pigments, Add additives such as leveling agents, antioxidants, ultraviolet absorbers, light stabilizers, plasticizers, surfactants, etc., add the polyisocyanate composition of this embodiment as a curing agent, and further add a solvent if necessary. After adding and adjusting a viscosity, it is obtained by stirring by hand stirring or stirring apparatuses, such as a mazeller.

  The resin component preferably contains a compound having two or more active hydrogens having reactivity with an isocyanate group in the molecule. Although it does not specifically limit as a compound which has two or more active hydrogen in a molecule | numerator, For example, a polyol, polyamine, polythiol etc. are mentioned. Among these, a polyol is more preferable. Specific examples of the polyol are not particularly limited, and examples thereof include polyester polyol, polyether polyol, acrylic polyol, polyolefin polyol, and fluorine polyol.

  The polyester polyol is not particularly limited. For example, dibasic acids such as succinic acid, adipic acid, dimer acid, maleic anhydride, phthalic anhydride, isophthalic acid, terephthalic acid, and carboxylic acids such as 1,4-cyclohexanedicarboxylic acid. Or a mixture of such as ethylene glycol, propylene glycol, diethylene glycol, 1,4-butanediol, neopentyl glycol, 1,6-hexanediol, trimethylpentanediol, cyclohexanediol, trimethylolpropane, glycerin, pentaerythritol, 2 -It can be obtained by subjecting a polyhydric alcohol such as methylolpropanediol and ethoxylated trimethylolpropane alone or a mixture to a condensation reaction. For example, the condensation reaction can be performed by mixing the above components and heating at 160 ° C. or higher and 220 ° C. or lower. In addition, for example, polycaprolactones obtained by ring-opening polymerization of lactones such as ε-caprolactone using polyhydric alcohol can also be used as the polyester polyol. These polyester polyols can be modified using aromatic diisocyanates, aliphatic diisocyanates, alicyclic diisocyanates, and polyisocyanates obtained therefrom. In this case, an aliphatic diisocyanate, an alicyclic diisocyanate, and a polyisocyanate obtained therefrom are particularly preferable from the viewpoints of weather resistance, yellowing resistance, and the like. Moreover, it is although it does not specifically limit as a commercial item of a polyester polyol, For example, desmophen 670 (Bayer company make brand name) is mentioned.

  The polyether polyol is not particularly limited. For example, a polyvalent hydroxy compound alone or in a mixture thereof, a hydroxide (lithium, sodium, potassium, etc.), a strongly basic catalyst (alcolate, alkylamine, etc.), a complex metal cyanide compound Using a complex (metal porphyrin, hexacyanocobaltate zinc complex, etc.) etc., random or block alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, cyclohexene oxide, styrene oxide, etc.) or a mixture of polyhydric hydroxy compounds Polyether polyols obtained by addition, polyether polyols obtained by reacting polyamine compounds (ethylene diamines, etc.) with alkylene oxides; acrylic resins using these polyether polyols as a medium Obtained by polymerizing de like, it includes so-called polymer polyols.

  The polyvalent hydroxy compound is not particularly limited. For example, (i) diglycerin, ditrimethylolpropane, pentaerythritol, dipentaerythritol, (ii) erythritol, D-threitol, L-arabinitol, ribitol, xylitol, Sugar alcohol compounds such as sorbitol, mannitol, galactitol, rhamnitol, (iii) monosaccharides such as arabinose, ribose, xylose, glucose, mannose, galactose, fructose, sorbose, rhamnose, fucose, ribodesource, (iv) trehalose, Disaccharides such as sugar, maltose, cellobiose, gentiobiose, lactose, melibiose, (v) trisaccharides such as raffinose, gentianose, merecitose, (vi) stachyo Tetrasaccharides such as vinegar and the like.

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

  The acrylic polyol is not particularly limited. For example, acrylic esters having active hydrogen (such as 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, and 2-hydroxybutyl acrylate) and active hydrogen are included. Methacrylic acid esters (such as 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, 3-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate), glycerin, tri (Meth) acrylic acid esters having polyvalent active hydrogen such as (meth) acrylic acid monoester of triol such as methylolpropane; polyether polyols (polyethylene glycol, polypropylene glycol, polybutylene glycol, etc.), and Monoethers with (meth) acrylic acid esters having the following active hydrogens; adducts of glycidyl (meth) acrylates and monobasic acids such as acetic acid, propionic acid, p-tert-butylbenzoic acid; One or more selected from the group consisting of adducts obtained by ring-opening polymerization of lactones (ε-caprolactam, γ-valerolactone, etc.) to active hydrogen of (meth) acrylic acid esters having As an essential component, (meth) acrylic acid esters (methyl acrylate, ethyl acrylate, isopropyl acrylate, -n-butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, Isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, methacryl -N-hexyl, cyclohexyl methacrylate, lauryl methacrylate, glycidyl methacrylate, etc.), unsaturated carboxylic acids (acrylic acid, methacrylic acid, maleic acid, itaconic acid, etc.), unsaturated amides (acrylamide, N-methylolacrylamide, Diacetone acrylamide), vinyl monomers having hydrolyzable silyl groups (vinyl trimethoxysilane, vinylmethyldimethoxysilane, γ- (meth) acrylopropyltrimethoxysilane, etc.), other polymerizable monomers (styrene, vinyl) One or two or more selected from the group consisting of toluene, vinyl acetate, acrylonitrile, dibutyl fumarate and the like are copolymerized by a conventional method. Moreover, it is although it does not specifically limit as a commercial item, For example, ACRYDIC A801 (brand name made from DIC) is mentioned.

  In addition, the acrylic polyol is obtained by, for example, subjecting the above polymerizable monomer to solution polymerization in the presence of a radical polymerization initiator such as a known peroxide or azo compound, and diluting with an organic solvent or the like as necessary. can get.

  The fluorine polyol is not particularly limited as long as it contains a fluorine in the molecule. For example, fluoroolefins and cyclovinyl ethers disclosed in JP-A-57-341075 and JP-A-61-215311 And copolymers such as hydroxyalkyl vinyl ether and monocarboxylic acid vinyl ester.

  The hydroxyl value of the polyol described above is not particularly limited, but is preferably 30 mgKOH / g or more and 200 mgKOH / g or less, and the acid value of the polyol is not particularly limited, but is 0 mgKOH / g or more and 30 mgKOH / g or less. preferable. The hydroxyl value can be measured according to JIS K1557. The acid value can be measured according to JIS-K1557-5.

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

  The equivalent ratio (NCO / OH molar ratio) of the isocyanate group of the polyisocyanate composition of the present embodiment to the hydroxyl group of the compound (compound) having two or more active hydrogens in the molecule is preferably 0.2 or more. It is 5.0 or less, More preferably, it is 0.4 or more and 3.0 or less, More preferably, it is 0.5 or more and 2.0 or less. By setting the equivalent ratio to 0.2 or more, it is possible to obtain a tougher coating film. By setting the equivalent ratio to 5.0 or less, the smoothness of the coating film tends to be further improved.

  The coating composition may contain a melamine curing agent such as a complete alkyl type, a methylol type alkyl, and an iminoxy type alkyl as necessary.

  Any of the compound having two or more active hydrogens in the molecule, the polyisocyanate composition, the coating composition, and the coating composition of the present embodiment can be used by mixing with an organic solvent. The organic solvent is not particularly limited, but an organic solvent having no functional group that reacts with a hydroxyl group and an isocyanate group is preferable. An organic solvent compatible with the polyisocyanate composition is preferred. Examples of such organic solvents include, but are not limited to, ester compounds, ether compounds, ketone compounds, aromatic compounds, ethylene glycol dialkyl ether compounds, and polyethylene glycol dicarboxylate compounds that are generally used as paint solvents. These compounds, hydrocarbon solvents, and aromatic solvents.

  The compound having two or more active hydrogens in the molecule, the polyisocyanate composition, the coating composition, and the coating composition of the present embodiment do not impair the effects of the present embodiment depending on the purpose and application. Various additives used in the technical field such as curing accelerators, pigments, leveling agents, antioxidants, UV absorbers, light stabilizers, plasticizers, surfactants, etc. You can also

  Although it does not specifically limit as a catalyst for hardening acceleration | stimulation, For example, metal salts, such as dibutyltin dilaurate, tin 2-ethylhexanoate, zinc 2-ethylhexanoate, cobalt salt; Triethylamine, pyridine, methylpyridine, benzyldimethylamine And tertiary amines such as N, N-dimethylcyclohexylamine, N-methylpiperidine, pentamethyldiethylenetriamine, N, N′-endoethylenepiperazine, N, N′-dimethylpiperazine, and the like.

  The coating composition containing the polyisocyanate composition of the present embodiment as a curing agent can be used as a coating such as roll coating, curtain flow coating, spray coating, bell coating, and electrostatic coating.

  The coating composition containing the polyisocyanate composition of the present embodiment includes various metals such as iron, plated steel sheet, stainless steel, and aluminum, materials such as plastic, wood, film, inorganic material, primer, top intermediate coating film, It can be painted on pre-coated metal and automobile coatings to obtain a painted product. The coated product thus obtained is useful because it imparts cosmetics, weather resistance, acid resistance, rust resistance, chipping resistance, and the like. Moreover, the polyisocyanate composition of this embodiment is useful also as urethane raw materials, such as an adhesive agent, an adhesive, an elastomer, a foam, and a surface treating agent.

  Hereinafter, the present embodiment will be described more specifically with specific examples and comparative examples. However, the present embodiment is not limited to these examples and comparative examples unless they exceed the gist thereof. Absent. The physical properties and evaluation in Examples and Comparative Examples described later were measured and evaluated by the following methods.

(Physical Property 1) Number Average Molecular Weight The number average molecular weight of the polyisocyanate composition was determined as a polystyrene-based number average molecular weight by gel permeation chromatograph (hereinafter simply referred to as “GPC”) measurement using the following apparatus.
Apparatus: Product name “HLC-802A” manufactured by Tosoh Corporation
Column: product name “G1000HXL” × 1 manufactured by Tosoh Corporation, product name “G2000HXL” × 1, product name “G3000HXL” × 1 carrier: tetrahydrofuran detection method: differential refractometer

(Physical Property 2) Isocyanate Cyclic Trimer Concentration The peak concentration of the molecular weight equivalent to the diisocyanate cyclic trimer obtained by the GPC measurement of (Physical Property 1) (for example, molecular weight: 504 for HDI cyclic trimer) It was determined as a percentage of the total peak area obtained.

(Physical Property 3) Allophanate Bond Concentration Using a polyisocyanate composition as a sample, the ratio of urethane groups and allophanate groups was determined by performing ¹ H-NMR measurement of the sample. The measurement was specifically performed under the following measurement conditions.
¹ H-NMR apparatus: RESONANCE EC400 (trade name, manufactured by JEOL)
Observation nucleus (frequency): 1H (400MHz)
Solvent (sample concentration): CDCL ₃ (5 mass / vol%)
Integration count: 256 times Measurement temperature: 50 ° C
Chemical shift standard: TMS 0ppm
About the measurement result obtained by the above measurement, the integral value of the signal is divided by the number of carbons to be measured to obtain the molar ratio of urethane group and allophanate group, and the allophanate binding concentration is obtained from the value. The classification was based on the following criteria. The allophanate binding concentration decreases in the order of ◎, ○, ×.
Molar ratio of urethane group: around 4.7 ppm: integral value / 1
Allophanate group molar ratio: around 8.5 ppm: integral value ÷ 1
Allophanate bond concentration = [allophanate group molar ratio / (allophanate group molar ratio + urethane group molar ratio)]
◎: Allophanate binding concentration is 0.9 or more ○: Allophanate binding concentration is less than 0.9 0.1 or more ×: Allophanate binding concentration is less than 0.1

(Physical property 4) Viscosity The viscosity of the obtained polyisocyanate composition was measured at 25 ° C. using an E-type viscometer (manufactured by Tokimec). In the measurement, a standard rotor (1 ° 34 ′ × R24) was used. The number of rotations was as follows.
100 rpm (when less than 128 mPa · s)
50 rpm (128 mPa · s or more and less than 256 mPa · s)
20 rpm (256 mPa · s or more and less than 640 mPa · s)
10 rpm (when 640 mPa · s or more and less than 1280 mPa · s)
5.0 rpm (when it is 1280 mPa · s or more and less than 2560 mPa · s)

(Physical property 5) Chromaticity The chromaticity of the obtained polyisocyanate composition was measured by the coloring degree (Hazen color number). The Hazen color number was measured according to JIS K0071-1.

(Physical property 6) NCO content rate Using the obtained polyisocyanate composition as a sample, the NCO content rate (% by mass) was determined by back titration with 1N hydrochloric acid after neutralizing the isocyanate group in the sample with excess 2N amine. It was. In addition, the non-volatile content of the polyisocyanate composition produced by the Example and comparative example which are mentioned later was investigated by the method mentioned above, and the thing whose value was 98 mass% or more was measured as it was.

(Physical Property 7) HDI Monomer Concentration Using the obtained polyisocyanate composition as a sample, a 20 mL sample bottle was first placed on a digital balance and about 1 g of the sample was precisely weighed. Next, 0.03 g to 0.04 g of nitrobenzene (internal standard solution) was added and precisely weighed. Finally, after adding about 9 mL of ethyl acetate, the lid was tightly mixed well to prepare the sample. The prepared adjustment liquid was analyzed by gas chromatography using the following apparatus and conditions to determine the HDI monomer concentration.
Apparatus: Product name “GC-8A” manufactured by Shimadzu Corporation
Column: Product name “Silicon OV-17” manufactured by Shinwa Kako Co., Ltd.
Column oven temperature: 120 ° C
Injection / detector temperature: 160 ° C

(Physical property 8) Isocyanate average functional group number The isocyanate average functional group number was calculated by the following general formula (2) from the number average molecular weight of the above (Physical property 1) and the NCO content (isocyanate concentration) of the above (Physical property 6).

(Evaluation 1) Change in chromaticity before and after storage The obtained polyisocyanate composition was added to a sample bottle, stored at 50 ° C. for 30 days, and the degree of coloration (Hazen color number) after storage was measured. The Hazen color number was measured according to JIS K0071-1. The following criteria were used to evaluate the Hazen color number measured in the above (Physical Property 5) from the numerical value of the increased Hazen color number after storage. The change in chromaticity before and after storage increases in the order of ◎, ○, △, ×.
A: Increased numerical value is less than 50 ○: Increased numerical value is 50 or more and less than 75 Δ: Increased numerical value is 75 or more and less than 100 ×: Increased numerical value is 100 or more

(Evaluation 2) Viscosity change before and after storage The obtained polyisocyanate composition was added to a sample bottle, stored at 50 ° C. for 30 days, and the viscosity after storage was measured under the same measurement conditions as the above physical properties (4). It was measured. From the ratio (%) of the change in viscosity after storage with respect to the viscosity measured in the physical property (4), the following criteria were used for evaluation. It shows that the change in viscosity before and after storage increases in the order of ◎, ○, Δ, ×.
A: Changed rate is less than 7.5% B: Changed rate is 7.5% or more and less than 10.0% Δ: Changed rate is 10.0% or more and less than 15.0% X: Changed rate is 15 0.0% or more

(Evaluation 3) NCO content change before and after storage The obtained polyisocyanate composition was added to a sample bottle, stored at 50 ° C. for 30 days, and under the same measurement conditions as the above physical properties (6), The NCO content was measured. From the ratio (%) at which the NCO content after storage was decreased with respect to the NCO content measured in the above physical property (6), the following criteria were used for evaluation. The change in NCO content before and after storage increases in the order of ○, Δ, ×.
○: Decreasing rate is less than 0.10% Δ: Decreasing rate is 0.10% or more and less than 0.20% ×: Decreasing rate is 0.20% or more

(Evaluation 4) Gel fraction After the coating film which had been cured at 20 ° C for 1 day was measured for its mass, it was immersed in acetone at 20 ° C for 24 hours. The mass of the undissolved part remaining after immersion was measured, the ratio with respect to the mass before immersion was calculated | required, and the gel fraction was evaluated on the following references | standards. It shows that the gel fraction becomes small in order of (circle) and x.
○: 80% or more ×: less than 80% In the case of a paint film using an epoxy polyol as the main agent, acetone was used instead of methanol.

(Evaluation 5) Sagging property The coating solution was applied to a vertical surface with an air spray gun so that the dry film thickness was 100 microns, and sagging property was evaluated according to the following criteria.
○: No sagging from the painted surface ×: Sagging from the painted surface

<Example 1>
A four-necked flask equipped with a stirrer, thermometer, reflux condenser, nitrogen blowing tube, and dropping funnel was placed in a nitrogen atmosphere, and 600 parts of HDI, a polyether polyol (trade name “ADEKA” from Adeka) 159 parts (equivalent ratio of isocyanate group / hydroxyl group (NCO / OH) 5/1) of “New Polyol WR-474”, which is simply “WR-474” in Table 1), and the reactor internal temperature is 120 ° C. with stirring. Hold for 3 hours. The reaction solution temperature was lowered, and unreacted HDI was removed using a thin film evaporator. The molecular weight of the reaction product was measured by GPC, and the isocyanate concentration was measured by titration to confirm that polyisocyanate was produced. To this polyisocyanate, 500 mass ppm of Adeka Stub HP1500 (trade name, manufactured by Adeka Company) was added and stirred at 50 ° C. for 1 hour in a nitrogen atmosphere to obtain a polyisocyanate composition. The resulting polyisocyanate composition had a viscosity at 25 ° C. of 20,000 mPa · s, an NCO content of 13.2%, a number average molecular weight of 1,690, an isocyanate average functional group number of 5.3, and an isocyanate cyclic 3 The monomer concentration was 1.7%. Moreover, the allophanate bond density | concentration of this polyisocyanate composition was a class of (circle).

<Examples 2-16, Comparative Examples 1-2, and Comparative Examples 4-7>
About Examples 2-16, Comparative Examples 1-2, and Comparative Examples 4-7, it reacted on the reaction conditions shown in Table 1 using the apparatus similar to Example 1, and was the same method as Example 1. Unreacted HDI was removed to obtain polyisocyanate. A polyisocyanate composition was obtained in the same manner as in Example 1 except that a predetermined amount of the phosphorous acid triester compound shown in Table 1 was added to the obtained polyisocyanate. Table 1 shows the physical properties of the obtained polyisocyanate composition. In Table 1, “SP-600” is a polyether polyol (trade name “ADEKA NEW POLYOL SP-600” manufactured by ADEKA) which is a hexavalent hydroxyl compound, and “SP-800” is a polyvalent hydroxyl compound. Ether polyol (trade name “Adeka New Polyol SP-800” manufactured by Adeka), “HP-2000” is a polyether polyol which is a pentavalent hydroxyl compound (trade name “Adeka New Polyol HP-2000” manufactured by Adeka) , “HP-1030” is a polyether polyol (trade name “ADEKA NEW POLYOL HP-1030” manufactured by ADEKA Corporation) which is a pentavalent hydroxyl compound, and “P-400” is a polyether polyol (ADEKA) which is a divalent hydroxyl compound. Product name "Adeka New Polyol P-400""G-400" indicates a polyhydroxy compound polyether polyol is a trivalent hydroxyl compound (Adeka Co., Ltd. under the trade name "Adeka New Polyol G-400"). In Table 1, “SUMILIZER GP” (trade name, manufactured by Sumitomo Chemical Co., Ltd.) is 6- [3- (3-t-butyl-4-hydroxy5-methylphenyl) propoxy] -2,4,8, 10-tetra-t-butyldibenz [d, f] [1,3,2] zodioxaphosphepine, “Adeka Stub HP10” (trade name, manufactured by Adeka) is 2,2-methylenebis (4,6-di-). -T-butylphenyl) octyl phosphite, "JP333E" (trade name, manufactured by Johoku Chemical Industry Co., Ltd.) is tris (tridecyl) phosphite, and "IRGAFOS168" (trade name, manufactured by BASF Corporation) is tris (2,4-diphenyl). A phosphorous acid triester compound of -t-butylphenyl) phosphite is shown.

<Comparative Example 3>
In the same apparatus as in Example 1, 600 parts of HDI and 11 parts of 1,3-butanediol were charged, and the temperature in the reactor was maintained at 80 ° C. for 2 hours with stirring in a nitrogen atmosphere. Thereafter, the internal temperature of the reactor was maintained at 60 ° C. for 4 hours, isocyanurate-forming reaction catalyst tetramethylammonium capriate was added, and when the yield reached 28%, phosphoric acid was added to stop the reaction. After filtering the reaction solution, unreacted HDI was removed using a thin film evaporator to obtain polyisocyanate. A polyisocyanate composition was obtained in the same manner as in Example 1 except that a predetermined amount of the phosphorous acid triester compound shown in Table 1 was added to the obtained polyisocyanate. Table 1 shows the physical properties of the obtained polyisocyanate composition.

<Example 17>
A polyisocyanate composition obtained in Example 1 as a curing agent, and an acrylic polyol (trade name “Acrydic A801” manufactured by DIC, simply “A801” in Table 2, resin hydroxyl group: 100 mgKOH / g) as a main agent, Was mixed so that the equivalent ratio of isocyanate / hydroxyl group was 1.0, and the mass ratio of ethyl acetate / toluene / butyl acetate / xylene / propylene glycol monomethyl ether acetate as a thinner was 30/30/20/15/5. Of Ford cup # 4 and adjusted to 20 seconds / 20 ° C. When the sagging property of the coated surface was evaluated using the obtained coating solution, sagging was not generated and the sagging property was good. The gel fraction measured after drying the coated coating film at 20 ° C. for one day was evaluated as “good”.

<Example 18>
A polyester polyol (trade name “Desmophen 670” manufactured by Bayer, simply “670”, hydroxyl group concentration: 3.4%) in Table 2) was used instead of the acrylic polyol used in Example 17. In the same manner as in Example 17, coating was performed and evaluated. There was no sagging, and the gel fraction of the paint film was evaluated as ○.

<Examples 19 to 33>
It carried out similarly to Example 17 except having used the main ingredient and hardening | curing agent which are shown in Table 2. The obtained results are shown in Table 2.

<Comparative Examples 8-14>
It carried out like Example 17 except having used the hardening agent shown in Table 2. The obtained results are shown in Table 2.

  From the above, it was confirmed that the polyisocyanate composition of each Example had small changes in chromaticity, viscosity, and NCO content before and after storage, and was excellent in curability and sagging when used in a paint.

  The polyisocyanate composition according to the present invention is used as a curing agent in a coating composition, and can be used as a coating such as roll coating, curtain flow coating, spray coating, bell coating, and electrostatic coating. Moreover, the said coating composition can be used as a primer for materials, such as a steel plate and a surface-treated steel plate, plastics, a timber, a film, an inorganic material, and a top intermediate coating. Furthermore, the coated product obtained by the coating composition is useful as a coated product that imparts heat resistance, cosmetic properties (surface smoothness, sharpness) and the like to pre-coated metal including an anti-rust steel plate, automobile coating, and the like. Furthermore, the coating composition is also useful as a raw material for urethane such as adhesives, pressure-sensitive adhesives, elastomers, foams, and surface treatment agents.

Claims (4)

A polyisocyanate obtained from one or more selected from the group consisting of an aliphatic diisocyanate and an alicyclic diisocyanate, and a polyvalent hydroxy compound having a hydroxyl group average functional group number of 4.0 or more and 10 or less;
A polyisocyanate composition containing a phosphorous acid triester compound represented by the following formula (I):
The polyisocyanate composition contains 10 mass ppm or more and 10000 mass ppm or less of the phosphorous acid triester compound with respect to the total amount of the polyisocyanate composition, and satisfies all of the following (1) to (4). Isocyanate composition.
P (OR ₁ ) (OR ₂ ) (OR ₃ ) (I)
(In formula (I), R ₁ , R ₂ , and R ₃ each independently represents a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms, or an aryl group.)
(1) Isocyanate average functional group number is 4.0 or more and 20 or less (2) Isocyanate concentration is 5.0% by mass or more and 20% by weight or less (3) Viscosity is 2000 mPa · s / 25 ° C. or more and 200,000 mPa.s. s / 25 ° C. or less (4) Isocyanate cyclic trimer concentration is 10% by mass or less   The polyisocyanate composition according to claim 1, wherein the polyisocyanate has an allophanate bond and a urethane bond in its structure.   The polyisocyanate composition according to claim 1 or 2, wherein the polyvalent hydroxy compound is one or more selected from the group consisting of a propylene oxide adduct polyether polyol and a polyester polyol. A polyisocyanate is obtained by reacting one or more selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates with a polyvalent hydroxy compound having a hydroxyl group average functional group number of 4.0 or more and 10 or less. A reaction process;
Mixing the polyisocyanate and a phosphorous acid triester compound represented by the following formula (I) to obtain a polyisocyanate composition,
The polyisocyanate composition contains 10 mass ppm or more and 10000 mass ppm or less of the phosphorous acid triester compound with respect to the total amount of the polyisocyanate composition, and satisfies all of the following (1) to (4). A method for producing a polyisocyanate composition.
P (OR ₁ ) (OR ₂ ) (OR ₃ ) (I)
(In formula (I), R ₁ , R ₂ , and R ₃ each independently represents a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms, or an aryl group.)
(1) Isocyanate average functional group number is 4.0 or more and 20 or less (2) Isocyanate concentration is 5.0% by mass or more and 20% by weight or less (3) Viscosity is 2000 mPa · s / 25 ° C. or more and 200,000 mPa.s. s / 25 ° C. or less (4) Isocyanate cyclic trimer concentration is 10% by mass or less