JPH11256102A - Moisture-setting type coating composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a moisture-setting type coating composition suitable for coating materials, sealants and adhesives showing resistance to weather, light and yellow discoloration, and also resistance to chemicals, e.g. acids, alkalis and solvents, of the required characteristics of resistance to weather, light, yellow discoloration, acids, solvents, water and alkalis. SOLUTION: This composition gives a coated film, which, after being set, holds at least 70% of the initial glossiness of the surface contaminated with 5 wt./vol.% aqueous solution of sodium hydroxide and 5 wt./vol.% aqueous solution of sulfuric acid for 168 h, when the initial surface glossiness is at least 70%. The coating film surface also holds, after being set, at least 70% of the initial glossiness and a color difference (ΔE) of 2 or less when it has an initial glossiness of at least 70% and is treated by a sunshine weather-O-meter for 1000 h.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moisture-curable paint composition applicable to paints, sealants, adhesives and the like.

[0002]

2. Description of the Related Art Conventionally, a paint made of a polyurethane resin (hereinafter referred to as a polyurethane resin paint) has a rubber elasticity,
Because of its excellent abrasion resistance, durability, weather resistance, and adhesion to a substrate, it has been used for anticorrosion, waterproof, floor and wall applications. As the types of these polyurethane resin paints, a one-pack type and a two-pack type are known. Among them, the moisture-curable polyurethane resin paint composed of a moisture-curable resin that is a one-pack type polyurethane resin reacts promptly with moisture in the air,
Due to its curing, it is widely used in paints, sealants, flooring, walling, waterproofing and adhesive applications. One of its features is that it is a one-pack type, so there is no need for weighing and mixing operations during painting. In addition, even under a low-temperature or high-humidity environment, it easily reacts with water and hardens, so that there are few restrictions on environmental conditions that can be applied. In particular, on the construction surface, there is no curing failure of the coating film or the like due to measurement error, and the construction time can be significantly reduced. However, conventional moisture-curable polyurethane resins are inferior in chemical resistance (solvent resistance, alkali resistance, acid resistance) and water resistance as compared with two-component polyurethane resin paint, fluororesin paint, silicone resin paint, etc. In particular, there has been a major problem in using it for exterior applications such as various top coatings.

[0003] As a conventional one-pack type moisture-curable polyurethane resin paint, there has been proposed a one-component moisture-curable polyurethane resin paint synthesized from various polyols and polyisocyanates. The performance of this paint depends on polyol and polyisocyanate which are resin raw materials. As for the polyisocyanate, chemical resistance, water resistance and weather resistance can be improved by using an aliphatic or alicyclic polyisocyanate such as hexamethylene diisocyanate or isophorone diisocyanate or an adduct thereof. However, for polyols, it is known that polyether polyols are useful for alkali resistance and water resistance, and polyester polyols are useful for acid resistance and weather resistance, but required properties such as chemical resistance, water resistance and weather resistance are known. And a polyol which can be used for exterior as a resin raw material of a one-component moisture-curable polyurethane resin coating material has not been found. For this reason, there has been a problem that the use of the conventional moisture-curable polyurethane resin paint is limited to interior use.

[0004]

The inventors of the present invention have developed a demand for properties such as chemical resistance (solvent resistance, alkali resistance, and acid resistance), water resistance, weather resistance, light resistance, and yellowing resistance. Paints and sealants by using modified polyisocyanates, which are excellent in both durability, such as weather resistance, light resistance, yellowing resistance, and water resistance, and chemical resistance such as acid resistance, alkali resistance, and solvent resistance. It is an object of the present invention to provide a moisture-curable coating composition suitable for use in adhesives and the like.

[0005]

Means for Solving the Problems In order to achieve the above object, the present inventors have developed a polyether polyol-modified polyisocyanate obtained by modifying a polyether polyol having excellent water resistance, alkali resistance and solvent resistance. , Weather resistance, light resistance, yellowing resistance, acid resistance, polyester polyol modified polyisocyanate obtained by modifying the polyester polyol excellent in solvent resistance and the like, in combination, containing both as a main component, weather resistance, Moisture curability that can provide coatings, sealants, adhesives, etc. that are both excellent in durability such as light resistance, yellowing resistance, water resistance and chemical resistance such as acid resistance, alkali resistance, solvent resistance etc. We have found a coating composition and arrived at the present invention.

That is, the present invention relates to a method for depositing a solution in which a 5 w / v% aqueous solution of sodium hydroxide and a 5 w / v% aqueous solution of sulfuric acid adhere to the surface of a coating film having a surface gloss value of 70% or more after curing. A moisture-curable coating composition having a retention rate of a surface gloss value after 168 hours of 70% or more, and a modified polyisocyanate obtained by reacting a polyol with a polyisocyanate, A moisture-curable coating composition comprising a polyether polyol-modified polyisocyanate obtained from a polyether polyol and a polyisocyanate, and a polyester polyol-modified polyisocyanate obtained from a polyester polyol and a polyisocyanate.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The performance of the moisture-curable coating composition of the present invention can be evaluated from the performance of a coating film after being applied on a flat plate such as a steel plate and sufficiently cured. The main required performance in the use application is chemical resistance (alkali resistance, acid resistance, solvent resistance) and durability (weather resistance, light resistance, yellowing resistance, water resistance) as a coating film after curing.

[0008] The method for evaluating such chemical resistance is not particularly limited, but it is preferable to conform to JIS K5658 "Polyurethane resin paint for steel structures". Specifically, the alkali resistance is immersed in a 5 w / v% sodium hydroxide aqueous solution at 20 ± 1 ° C. or an adhesion test, and the acid resistance is immersed in a 5 w / v% sulfuric acid aqueous solution at 20 ± 1 ° C. In the adhesion test, the retention rate of the surface gloss value for each test time of 168 hours or more (hereinafter, referred to as gloss retention rate).
Is 70% or more, preferably 80% or more, and more preferably 90% or more. When the gloss retention is less than 70%, there is a problem particularly in terms of durability as a topcoat for exterior use.

For the evaluation of the weather resistance, an exposure test using a sunshine weather o meter is suitably used. Specifically, it is preferable that the gloss retention after 1000 hours of the exposure test is 70% or more and the color difference (ΔE value) is 2 or less. When the gloss retention is less than 70%, there is a problem in long-term use as a topcoat for exterior use in high-gloss applications, and when the color difference (ΔE value) exceeds 2, especially when used as a topcoat for exterior, There is a problem with color retention.

[0010] The moisture-curable coating composition of the present invention contains a modified polyisocyanate obtained by reacting a polyol with a polyisocyanate. In addition, satisfying both the chemical resistance (alkali resistance, acid resistance, and solvent resistance) and durability (weather resistance, light resistance, yellowing resistance, and water resistance) of the cured coating film means that the coating film must have water resistance, Modified polyisocyanate obtained from polyether polyol and polyisocyanate having excellent alkalinity and solvent resistance (hereinafter referred to as polyether polyol-modified polyisocyanate), and weather resistance, light resistance, yellowing resistance, acid resistance, and solvent resistance This is achieved by a product containing a modified polyisocyanate obtained from a polyester polyol and a polyisocyanate having excellent properties and the like (hereinafter, referred to as a polyester polyol-modified polyisocyanate).

Further, with respect to the modified polyisocyanate contained in the moisture-curable coating composition of the present invention, the weight ratio of the contained polyether polyol-modified polyisocyanate to polyester polyol-modified polyisocyanate is 8%.
0 / 20-30 / 70 is preferred, and 70 / 30-50 /
50 is more preferred. The weight ratio is 100/0 to 80/2
If it is less than 0, chemical resistance (acid resistance) and durability (weather resistance, light resistance, yellowing resistance) are insufficient, and the weight ratio is 3
If it exceeds 0/70 to 0/100, chemical resistance (alkali resistance) is insufficient, and it is particularly difficult to use it as a top coat for exterior use.

The modified polyisocyanate preferably contained in the moisture-curable coating composition of the present invention is not particularly limited, but is synthesized from a polyol and a polyisocyanate.

The polyol used as a raw material of the modified polyisocyanate of the present invention is not particularly limited, but includes polyether polyols, polyester polyols, polyether ester polyols,
Polyalkylene polyols, polycarbonate polyols, polyacryl polyols, and silicone polyols are used, and among them, polyether polyols and polyester polyols are more preferably used. Any of these polyols is preferably used as a diol compound or a trifunctional or higher functional polyol compound.

As the polyether polyol, any commercially available one can be used, and the following general formula (1)
Are preferably used.

[0015]

Embedded image Here, in the formula, m and n are natural numbers, X is an alcohol residue, a carboxylic acid residue or a primary amine residue, R ¹ is a hydrocarbon group, and is partially substituted with N, O, and S atoms. You may. Specific examples of R ¹ include a methylene group, an ethylene group,
A linear alkylene group such as a 1,3-propylene group,
A branched alkylene group such as a propylene group, a 1,2-butylene group, a 1,3-butylene group, a 2-methyl-1,3-propylene group, a 1,1-cyclohexylene group,
An alicyclic hydrocarbon group such as a cyclohexylene group, a 1,3-cyclohexylene group, or a 1,4-cyclohexylene group, each of which may show one or more repeated structures. Further, R ¹ may be substituted with various substituents such as a halogeno group such as fluorine, chlorine, and bromine, a cyano group, a carboxyl group, a sulfonic acid group, a nitro group, a hydroxy group, and an alkoxy group. An unsaturated group such as a vinylene group, a carbonyl group, an oxyalkylene group, a thioalkylene group, a urethane group, a urea group, a thiourea group, etc., in the main chain, and an oxyalkyl group, a thioalkyl group, a carboxyl group, etc. in the side chain. Or, even if a plurality is included, there is no problem at all. R ¹ may be the same or different. As further specific examples of polyether polyol, ethylene glycol, propylene glycol, glycerin, ethylene oxide obtained using pentaeristol or the like as an initiator, a ring-opened polymer of a mixture of ethylene oxide and propylene oxide and tetrahydrofuran are more preferably used. Can be Furthermore, when the moisture-curable coating composition of the present invention is used as various overcoats, polytetramethylene excellent in flexibility, applicability, amorphousness, transparency, dispersibility with inorganic pigments, water resistance and alkali resistance is excellent. Glycol polyols are more preferred. In addition,
When the moisture-curable coating composition of the present invention is used as various top coatings, the number average molecular weight of such a polyether polyol is preferably from 200 to 2,000, more preferably from 300 to 1500.

Further, as the polyester polyol,
Any commercially available one can be used, but a polyester polyol represented by the following general formula (2) is preferably used.

[0017]

Embedded image Here, in the formula, m and n are natural numbers, Y is an alcohol residue, a carboxylic acid residue or a primary amine residue, R ² is a hydrocarbon group, and is partially substituted with N, O, and S atoms. You may. Specific examples of R ² include a methylene group, an ethylene group,
A linear alkylene group such as a 1,3-propylene group,
A branched alkylene group such as a propylene group, a 1,2-butylene group, a 1,3-butylene group, a 2-methyl-1,3-propylene group, a 1,1-cyclohexylene group,
An alicyclic hydrocarbon group such as a cyclohexylene group, a 1,3-cyclohexylene group, or a 1,4-cyclohexylene group, each of which may show one or more repeated structures. R ² may be substituted with various substituents such as a halogeno group such as fluorine, chlorine and bromine, a cyano group, a carboxyl group, a sulfonic acid group, a nitro group, a hydroxy group and an alkoxy group; An unsaturated group such as a vinylene group, a carbonyl group, a carboxyl group, an oxyalkylene group, a thioalkylene group, a urethane group, a urea group, a thiourea group, or the like in a main chain, and an oxyalkyl group, a thioalkyl group, a carboxyl group, or the like in a side chain. There may be no problem even if one or more of them are included. Also,
R ² may be the same or different. Further specific examples of polyester polyols include 2 or 3 such as maleic acid, fumaric acid, succinic acid, adipic acid, sebacic acid, azelaic acid, phthalic acid, isophthalic acid, terephthalic acid and trimellitic acid.
A condensate of a basic acid and a divalent to tetravalent polyhydric alcohol is used. Specific examples of such polyhydric alcohols include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol,
1,3-butylene glycol, 1,4-butylene glycol, 1,5-pentene glycol, 1,6-hexylene glycol, neopentyl glycol, decamethylene glycol, 2,4,4-trimethyl-1,3-pentane Glycol, cyclohexanediol, xylylene glycol, hydroquinone bis (hydroxyethyl ether), hydrogenated bisphenol A, trimethylolpropane, glycerin, 1,2,6-hexanetriol, pentaerythritol, castor oil and the like are used. Also,
Higher fatty acids having a hydroxyl group, for example, coconut oil fatty acids,
Linseed oil fatty acid, soybean oil fatty acid, cottonseed oil fatty acid, tung oil fatty acid, dimer acid, hydrogenated dimer acid, castor oil fatty acid, and the like are blended in an acid component to obtain an oil-modified polyester polyol. In the above, a polycaprolactone-based polyol in which R ² is a straight-chain pentylene group is more preferably used as a polyester polyol having excellent weather resistance, particularly yellowing resistance. Furthermore, when the moisture-curable coating composition of the present invention is used as various top-coating paints, from the viewpoint of flexibility, applicability, non-crystallinity, transparency and high gloss retention, aliphatic polyester polyol or polycaprolactone polyol is used. Has a number average molecular weight of preferably from 200 to 2,000, and more preferably from 300 to 1500.

Further, the polyetherester polyols used as a raw material of the modified polyisocyanate include those obtained by reacting the above-mentioned polyether polyol with a polybasic acid to form a polyester, or both segments of the polyether and polyester in the molecule. For example, a polyol obtained by ring-opening copolymerization of an epoxy compound and an acid anhydride is used.

As the polyalkylene polyol used as a raw material of the modified polyisocyanate, polybutadiene polyol, polyisoprene polyol and the like are used.

Further, as a raw material of the modified polyisocyanate, although not particularly limited, for example, a polycarbonate polyol having a structure represented by the following general formula (3) is also preferably used.

[0021]

Embedded image Here, in the formula, m and n are natural numbers, Z is an alcohol residue, a carboxylic acid residue or a primary amine residue, R ³ is a hydrocarbon group, and is partially substituted with N, O, and S atoms. You may. Specific examples of R ³ include a methylene group, an ethylene group,
A linear alkylene group such as a 1,3-propylene group,
A branched alkylene group such as a propylene group, a 1,2-butylene group, a 1,3-butylene group, a 2-methyl-1,3-propylene group, a 1,1-cyclohexylene group,
An alicyclic hydrocarbon group such as a cyclohexylene group, a 1,3-cyclohexylene group or a 1,4-cyclohexylene group; a bisphenol group such as bisphenol A, bisphenol F, and bisphenol S;
In some cases, the structure may be repeated more than twice. Also, R
³ may be substituted with various substituents such as a halogeno group such as fluorine, chlorine and bromine, a cyano group, a carboxyl group, a sulfonic acid group, a nitro group, a hydroxy group and an alkoxy group. R ³ has an unsaturated group such as a vinylene group, a carbonyl group, an oxyalkylene group, a thioalkylene group, a urethane group, a urea group, a thiourea group, or the like as a main chain, and an oxyalkyl group, a thioalkyl group, a carboxyl group, or the like. There may be no problem even if one or more are included in the side chains. R ³ may be the same or different. Among them, an aliphatic polycarbonate polyol in which R ³ is a linear alkylene group is more preferably used as a polycarbonate polyol having excellent weather resistance, particularly yellowing resistance. Further, when the moisture-curable coating composition of the present invention is used as various top coatings, the number average molecular weight of the aliphatic polycarbonate polyol is from the viewpoint of flexibility, applicability, amorphousness, transparency, and high gloss retention. , 300-200
0 is preferable, and more preferably 500 to 1500 is used.

The type of polyacryl polyol used as a raw material of the modified polyisocyanate is not particularly limited, but acrylic diol is preferably used. Specific examples of such an acrylic diol include various acrylic acid monomers, for example, when polymerizing acrylic esters such as methyl methacrylate, propyl methacrylate, and isobutyl methacrylate, the following general formula (4) or ( Polyacryldiols modified with OH groups at both terminals obtained by functioning as a hydroxyl group initiator, a terminator, and a chain transfer agent such as the compound represented by 5) are preferably used.

[0023]

Embedded image

Embedded image However, in the formula, R ⁴ , R ⁵ , R ⁸ and R ⁹ represent a linear alkylene group such as a methylene group, an ethylene group, a 1,3-propylene group, a 1,2-propylene group, a 1,2-butylene group 1,3-butylene group, branched alkylene group such as 2-methyl-1,3-propylene group, 1,1-cyclohexylene group, 1,2-cyclohexylene group, 1,3-cyclohexylene Or an alicyclic hydrocarbon group such as a 1,4-cyclohexylene group, an arylene group such as a phenylene group or a naphthylene group, an oxyalkyl group such as an oxymethylene group or an oxypropylene group, bisphenol A, bisphenol F, bisphenol One or more repeating structures such as bisphenol groups such as S, halogeno groups such as fluorine, chlorine and bromine, cyano groups, carboxyl groups, sulfonic acid groups, nitro groups May be substituted with various substituents such as b, hydroxy, and alkoxy groups, and may be an unsaturated group such as a vinylene group, a carbonyl group, a carboxyl group, an oxyalkyl group, a thioalkyl group, a urethane group, or a urea group. , A thiourea group or the like at the terminal, at both terminals, inside or in the repeating unit may be included at all. R ⁴ , R ⁵ , R ⁸ and R ⁹ may be the same or different. Further, in the formula, R ⁶ and R ⁷ are a methyl group, an ethyl group, a linear alkyl group such as a 1,3-propylene group, a 1,2-propylene group, a 1,2-butylene group,
Branched alkyl groups such as 1,3-butylene group and 2-methyl-1,3-propylene group, alicyclic hydrocarbon groups such as cyclohexyl group, allyl groups such as phenyl group and naphthyl group, and methoxy group , An ethoxy group, an alkoxy group such as a phenoxy group or a phenoxy group, an aralkyl group such as a benzyl group and a phenethyl group, a halogeno group such as fluorine, chlorine, and bromine, and a cyano group, and a halogeno group such as fluorine, chlorine, and bromine. May be substituted with various substituents such as cyano group, carboxyl group, sulfonic acid group, nitro group, hydroxy group and alkoxy group. Further, R ⁶ and R ⁷ each include one or more unsaturated groups such as a vinylene group, a carbonyl group, a carboxyl group, an oxyalkyl group, a thioalkyl group, a urethane group, a urea group, a thiourea group, or the like. There is no problem at all even if a plurality is included. Also, R ⁶ and R
⁷ may be the same or different. In addition, these hydroxyl group initiators, terminators and / or chain transfer agents can be used not only alone but also as a mixture of two or more.

Further, the silicone polyol used as a raw material of the modified polyisocyanate is not particularly limited, and for example, a polysiloxane modified with alcohol is preferably used. The substituent of the Si atom in the main chain is not particularly limited, but usually, an alkyl group such as a methyl group or an ethyl group, or an aromatic group such as a phenyl group is used. In addition, those substituted with various substituents such as a halogeno group such as fluorine, chlorine, and bromine, a cyano group, a carboxyl group, a sulfonic acid group, a nitro group, a hydroxy group, an alkoxy group, and a hydrogen atom are used.
Stability of bond between i atom and substituent, stability of silicone polyol-modified polyisocyanate, stability of moisture-curable coating composition, durability of paint, sealant, flooring agent, wall agent, waterproofing agent or adhesive Alkyl groups such as a methyl group and an ethyl group are more preferably used in view of various properties such as weather resistance and the like. Further, an unsaturated group such as a vinylene group, a carbonyl group, an oxyalkyl group, a thioalkyl group, a urethane group, a urea group, a thiourea group or the like in a main chain, a carboxyl group or the like at a terminal, an unsaturated group such as a vinylene group, Group, oxyalkylene group, thioalkylene group, urethane group, urea group, thiourea group, etc. in the main chain, and oxyalkyl group, thioalkyl group, carboxyl group, etc. No problem.

The number average molecular weight of the polyol used in the present invention is preferably from 200 to 10,000, more preferably from 300 to 5,000, even more preferably from 300 to 5,000.
3000 polyols are used. In addition, the moisture-curable coating composition of the present invention has sufficient fluidity, dispersibility of additives, workability such as coating and pouring, and sufficient crosslinkability and curing to maintain the durability of coating films, sealants, adhesive layers, and the like. Because it is necessary to balance the properties, a linear diol is used from the viewpoint of workability such as fluidity, additive dispersibility, application and injection, and a trifunctional or higher functional polyol is used from the viewpoint of sufficient crosslinkability and curability. Therefore, the polyol of the present invention is preferably used in combination with a linear diol and a trifunctional or higher functional polyol serving as a crosslinking component. Further, from the viewpoint of storage stability, it is more preferable to use a linear diol and a triol in combination.

The polyisocyanate used as a raw material of the modified polyisocyanate of the present invention is not particularly limited, but includes trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate,
1,2-propylene diisocyanate, 1,2-butylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, 2,4,4-
Trimethylhexamethylene diisocyanate, 2,2
4-trimethylhexamethylene diisocyanate, 2,
Aliphatic diisocyanate such as 6-diisocyanatomethylcaproate, 1,3-cyclopentane diisocyanate, 1,4-cyclohexane diisocyanate,
3-cyclohexane diisocyanate, 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate, 4,4'-methylenebis (cyclohexyl isocyanate), methyl-2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate, Cycloalkylene diisocyanates such as 1,4-bis (isocyanatomethyl) cyclohexane and 1,3-bis (isocyanatomethyl) cyclohexane, m-phenylene diisocyanate, p-phenylene diisocyanate, 4,4′-diphenyl diisocyanate, 5-naphthalenediisocyanate,
4,4'-diphenylmethane diisocyanate, 2,4
-Tolylene diisocyanate, 2,6-tolylene diisocyanate, 2,4-tolylene diisocyanate and 2,
A mixture of 6-tolylene diisocyanate, 4,4'-toluidine diisocyanate, 4,4'-toluidine diisocyanate, dianisidine diisocyanate,
Aromatic diisocyanates such as 4'-diphenyl ether diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, a mixture of 1,3-xylylene diisocyanate and 1,4-xylylene diisocyanate, ω, ω'- Diisocyanate
Araliphatic diisocyanates such as 1,4-dimethylbenzene, 1,3- or 1,4-bis (α, α-dimethylisocyanatomethyl) benzene, triphenylmethane-4,4 ′, 4 ″ -triisocyanate; 1,3,5-
Triisocyanates such as triisocyanatebenzene, 2,4,6-triisocyanatetoluene, 4,4'-
Tetraisocyanates such as diphenyldimethylmethane-2,2 ', 5,5'-tetraisocyanate are preferably used. Further, a polyisocyanate such as a polymerized polyisocyanate comprising the above-mentioned isocyanate compound such as a trimer of a dimer of tolylene diisocyanate and a polyphenylpolymethylene polyisocyanate are also preferably used. These compounds can be used alone or as a mixture of two or more.

Although the method for producing the modified polyisocyanate of the present invention is not particularly limited, a urethanization reaction between a polyol and a polyisocyanate is preferably used.
Specific methods include a method of adding and synthesizing a polyisocyanate to a polyol, a method of adding and synthesizing a polyol to a polyisocyanate, and a method of reacting an equivalent amount of a polyol and a polyisocyanate by a reaction equivalent. However, in order for only one isocyanate group in the polyisocyanate molecule to react with the hydroxyl group of the polyol and leave the other isocyanate group unreacted as a moisture-curable group, multiple isocyanate groups in the polyisocyanate molecule and the polyol It is necessary to prevent gelation of the reaction system (formation of solvent insolubles) due to the reaction with the hydroxyl group or runaway of such a reaction, and to make the polyisocyanate always excessively present as a reaction equivalent to the polyol in the reaction system, A method in which a polyol is added to polyisocyanate for synthesis is more preferable.

Furthermore, in the method of adding a polyol to a polyisocyanate and synthesizing the polyisocyanate, the addition is performed in multiple stages and for a long time in order to avoid a phenomenon in which the polyol concentration locally exceeds the polyisocyanate concentration as a reaction equivalent in the reaction system. It is preferably performed over Specifically, the number of addition steps is preferably 2 or more, more preferably 5 or more, and still more preferably an infinite number of steps, that is, a continuous dropping method. The addition reaction equivalent in each stage is not particularly limited, when the total number of moles of the polyisocyanate added per mole of the hydroxyl group in the polyol is 1 reaction equivalent, but it is preferable to reduce the addition reaction at the beginning of the reaction. As the specific addition time, the average addition rate is preferably from 0.1 to 5 reaction equivalents / hour, more preferably from 0.2 to 3 reaction equivalents / hour, more preferably from 0.2 to 3 reaction equivalents / hour. Preferably, it is not less than 0.3 reaction equivalents / hour and not more than 2 reaction equivalents / hour.

In the method for producing a modified polyisocyanate of the present invention, the amount of the polyisocyanate to be added per mol of the hydroxyl group in the polyol is preferably 0.7 to 0.9.
The amount is 8 mol, more preferably 0.8 to 0.95 mol, and still more preferably 0.85 to 0.95 mol. When the added amount of the polyisocyanate is less than 0.7 mol, the unreacted isocyanate group content of the resulting modified polyisocyanate and the moisture-curable coating composition of the present invention containing the modified polyisocyanate is reduced, and the moisture-curable Durability is greatly impaired due to poor curing of the coating film or the like made of the coating composition and a decrease in the crosslinking density. When the amount of the polyisocyanate exceeds 0.98 mol, a large amount of unreacted polyisocyanate remains in the moisture-curable coating composition, so that the moisture-curable coating composition is particularly used as various top coatings. In this case, the unreacted polyisocyanate is not preferable because it causes yellowing and chromaticity change of the cured coating film.

In the production of the modified polyisocyanate of the present invention, the polyol and the polyisocyanate as raw materials may be used as a solid content or as a solution with various solvents. It is preferably added as a solution with an organic solvent in order to improve reactivity, fluidity, and dispersibility of the additive. Addition of the organic solvent can facilitate dispersibility of the raw material, progress of the urethanization reaction, suppression of generation of solvent-insoluble components due to gelation of the reaction system, and the like. Examples of such an organic solvent include an organic solvent having no active hydrogen in order to maintain the reactivity of the unreacted isocyanate groups of the modified polyisocyanate and the moisture-curable coating composition of the present invention containing the modified polyisocyanate. Preferably, esters such as ethyl acetate, butyl acetate and cellosolve acetate; ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone; aromatic hydrocarbons such as benzene, toluene and xylene; cyclic ethers such as tetrahydrofuran, dioxane and trioxane And the like are preferably used. Among these organic solvents, acetone, cellosolve acetate, methyl ethyl ketone, methyl isobutyl ketone, toluene, xylene, tetrahydrofuran, dioxane and the like are more preferably used. In addition, these organic solvents are used not only alone but also as a mixture of two or more kinds.

In the production of the modified polyisocyanate of the present invention, a tertiary amine, a metal catalyst and the like are preferably added as a catalyst for urethanizing the polyol and the polyisocyanate.

Specific examples of such a tertiary amine include, for example, triethylenediamine, N, N, N ', N',
N '"-pentamethyldipropylenetriamine,
N, N, N ', N', N ""-pentamethyldiethylenetriamine, N, N, N ', N'-tetramethylhexamethylenediamine, bis (dimethylaminomethyl)
Ether, 2- (N, N-dimethylamino) ethyl-3
-(N, N-dimethylamino) propyl ether, N,
N-dimethylcyclohexylamine, N, N-dicyclohexylmethylamine, methylenebis (dimethylhexyl) amine, N, N-dimethylcetylamine, N, N-
Dimethyldodecylamine, N, N-dimethylhexadecylamine, N, N, N ', N'-tetramethyl-1,3
-Butanediamine, N, N-dimethylbenzylamine,
Morpholine, N-methylmorpholine, N-ethylmorpholine, N- (2-dimethylamino) morpholine, 4,
4'-oxydiethylenedimorpholine, N, N'-diethylpiperazine, N, N'-dimethylpiperazine, 2,
4,6-tri (dimethylaminomethyl) phenol, tetramethylguanidine, 3-dimethylamino-N, N '
-Dimethylpropionamide, N, N, N ', N "-tetra (3-dimethylaminopropyl) methanediamine;
N, N'-dimethylaminoethanol, ethoxylated hydroxylamine, N, N, N ', N'-tetramethyl-
1,3-diamino-2-propanol, N, N, N'-
Trimethylaminoethanolamine, 1,4-bis (2
-Hydroxypropyl) 2-piperazine, 1- (2-hydroxypropyl) imidazole, 3,3-diamino-
N-methyldipropylamine, 1,8-diazobicyclo [5.4.0] -undecene-7, N-methyl-N'-
Hydroxyethylpiperazine and the like are used. Of these, preferred are bis (dimethylaminomethyl) ether, 2- (N, N-dimethylamino) propyl ether, triethylamine, N- (2-dimethylaminoethyl) morpholine, and 3-dimethylamino-N, N-dimethyl. Propionamide and N, N-dimethylaminoethanol are used, and more preferably, triethylenediamine is used. These tertiary amines are used alone or as a mixture of two or more.

The amount of the tertiary amine to be added during the production of the modified polyisocyanate of the present invention is preferably 0.01 to 1 mol%, more preferably 0.01 to 1 mol%, in terms of amino group per mol of isocyanate groups of the modified polyisocyanate. 0.05-0.5 mol%, more preferably 0.05
~ 0.1 mol% is an appropriate amount. If the amount of the tertiary amine is less than 0.01 mol%, the urethane-forming reaction between the polyol and the polyisocyanate is not sufficiently completed, and a large amount of unreacted polyisocyanate is contained in the modified polyisocyanate and the moisture-curable coating composition of the present invention. , And tends to cause poor curing and poor durability of the coating film, sealant, adhesive layer, and the like obtained by the moisture-curable coating composition. In particular, when the moisture-curable coating composition is used as various overcoats, it is not preferable because it becomes a main factor in lowering the gloss retention of the cured coating film, yellowing and chromaticity of the cured coating film. When the amount of the tertiary amine exceeds 1 mol%,
In the urethanization reaction between the polyol and the polyisocyanate, the isocyanate groups in the reaction system react excessively to cause gelation, so that the yield of the modified polyisocyanate tends to deteriorate, and the moisture-curable coating composition When the product is used as various overcoats, an excessive amount of tertiary amine remaining in the coating film is not preferable because it causes yellowing and chromaticity change of the cured coating film.

Specific examples of the metal catalyst preferably added at the time of producing the modified polyisocyanate of the present invention include, for example, bismuth nitrate, lead 2-ethylhexonate, lead benzoate, lead oleate, sodium trichlorophenolate, sodium propionate , Lithium acetate, potassium oleate, tetrabutyltin, tin chloride, tributyltin cyanate, tin octylate, tin tartrate, dibutyltin di (2
-Ethylhexaate), dibutyltin dilaurate,
Dibutyltin diisooctyl maleate, dibutyltin dibutoxide, dibutyltin dibutoxide, dibutyltin bis (o-phenylphenate), dibutyltin bis (acetylacetonate), di (2-ethylhexyl) tin oxide, titanium tetrachloride, Dibutyl titanium chloride, tetrabutyl titanate, butoxy titanium trichloride, iron trichloride,
Iron (III) ethylhexonate, iron (III) acetylacetone, ferrocene, antimony trichloride, antimony pentachloride, triphenylantimony dichloride, triphenylantimony, uranium nitrate, cadmium nitrate, cadmium diethyldithiophosphate, cobalt benzoate, -Cobalt ethylhexonate, thorium nitrate, triphenylaluminum, aluminum oleate, diphenylmercury,
Zinc 2-ethylhexanoate, zinc naphthenate, nickelocene, hexacarbonylmolybdenum, cerium nitrate, vanadium trichloride, copper 2-ethylhexanoate, copper acetate,
-Manganese ethylhexonate, zirconium 2-ethylhexanoate, triphenylarsenic, arsenic trichloride, boron trifluoride-diethyl ether complex, pyridine borane, calcium acetate, barium acetate and the like are used. Further, in the moisture-curable coating composition of the present invention, an organic tin compound having a catalytic action in a reaction between an isocyanate group and a hydroxyl group is used as a metal catalyst more preferably added. Specifically, for example, tetra-n-butyl-
1,3-diacetyloxydistannoxane, tetra-n
-Propyl-1,3-diacetyloxydistannoxane, tetra-n-propyl-1-chloro-3-diacetyloxydistannoxane, tetra-n-butyl-1-chloro-3-diacetyloxydistannoxane, tetra Methyl-1,3-diacetyloxydistannoxane, tetra-n-butyl-1,3-diacryloxydistannoxane, tetra-n-butyl-1,3-dioleyloxydistannoxane, tetra-n- Butyl-1,3-diformyloxydistannoxane, tetra-n-butyl-1,
3-distearyloxydistannoxane, tetra-n-
Butyl-1,3-diphenylacetyloxydistannoxane, tetra-n-butyl-1,3-diisocyanooxydistannoxane, tetra-n-butyl-1-acetyloxy-3-hydroxydistannoxane, tetra -N-
Propyl-1-acetyloxy-3-hydroxydistannoxane, tetramethyl-1-acetyloxy-3-hydroxydistannoxane, tetra-n-butyl-1,3
-Dichlorodistannoxane, tetramethyl-1,3-dichlorodistannoxane, tetra-n-butyl-1,3-
Dipropoxydistannoxane, tetra-n-propyl-
1,3-dipropoxydistannoxane, tetra-n-butyl-1-propoxy-3-acetyloxydistannoxane, tetra-n-propyl-1-hydroxy-3-ethoxyoxydistannoxane, 1,1- Dibutyl-3,
3-Dipropyl-1-hydroxy-3-acetyloxydistannoxane, 1,3-dipropyl-1,3-dibutyl-1-chloro-3-hydroxydistannoxane and the like are used. More preferably, organotin compounds such as tin octylate, dibutyltin dilaurate, and distaquinosan are used. These metal catalysts can be used alone or
Used as a mixture of more than one species.

The amount of the metal catalyst added during the production of the modified polyisocyanate of the present invention is preferably 0.001 to 5% by weight, more preferably 0.01 to 1% by weight, based on the modified polyisocyanate. More preferably, the appropriate amount is 0.01 to 0.1% by weight. When the addition amount of the metal catalyst is less than 0.001% by weight, the urethane-forming reaction between the polyol and the polyisocyanate is not sufficiently completed, and the unreacted polyisocyanate contains the modified polyisocyanate and the moisture-curable composition of the present invention containing the modified polyisocyanate. Residue in the coating composition in large amounts, coating film obtained by the moisture-curable coating composition, sealant, poor curing of the adhesive layer,
It causes poor durability. In particular, when the moisture-curable coating composition of the present invention is used as various overcoats, it is not preferable because it becomes a main factor of a decrease in gloss retention of the cured coating film, yellowing and chromaticity change. If the addition amount exceeds 5% by weight, the isocyanate groups in the reaction system excessively react in the urethanization reaction between the polyol and the polyisocyanate to cause gelation. When the moisture-curable coating composition of the present invention tends to decrease in yield, and when the moisture-curable coating composition of the present invention is used as various top-coating paints, an excessive amount of the metal catalyst remaining in the coating film causes yellowing of the cured coating film. It is unfavorable because it causes a change in chromaticity.

Further, at the time of producing the modified polyisocyanate of the present invention, the tertiary amine and the metal catalyst are more preferably added in combination. The combined use of a tertiary amine and a metal catalyst makes it possible to reduce the absolute amount of the catalyst that sufficiently completes the urethanization reaction between the polyol and the polyisocyanate, and to obtain the modified polyisocyanate and the moisture of the present invention containing the modified polyisocyanate. In the curable coating composition, the content of a catalyst that causes yellowing and chromaticity change of a cured coating film or the like can be reduced, so that it is effective especially when the moisture-curable coating composition is used as various top coatings. It is.

The method for adding the tertiary amine and / or the metal catalyst during the production of the modified polyisocyanate of the present invention includes a method of adding a polyol or a solution containing a polyol, a method of adding a polyisocyanate or a solution containing a polyisocyanate. There is a method of adding both a polyol or a solution containing a polyol as a main component and a solution containing a polyisocyanate or a polyisocyanate, and the method is not particularly limited. In order to allow the reaction to proceed, it is preferable to add a tertiary amine and / or a metal catalyst to a polyisocyanate or a solution containing the polyisocyanate to be a reaction field.

The modified polyisocyanate 1 of the present invention
If the number of unreacted isocyanate groups per molecule is too large, the stability during storage of the modified polyisocyanate and the moisture-curable coating composition of the present invention containing the modified polyisocyanate tends to be poor, while if too small, the amount is too small. The coating film obtained from the moisture-curable coating composition has poor curing and / or
Alternatively, since the durability tends to be poor, the number of unreacted isocyanate groups is preferably from 2.0 to 3.0 per molecule, more preferably from 2.2 to 2.9, and still more preferably from 2.3 to 2.9. 8

In addition to the above-mentioned modified polyisocyanate, various additives can be added to the moisture-curable coating composition of the present invention. Specific examples include a curing catalyst, a pigment, a viscosity modifier, a leveling agent, an antifoaming agent, a dehydrating agent, an ultraviolet absorber,
Additives such as light stabilizers and antioxidants, and fillers such as talc, calcium carbonate, clay, glass flake, iron oxide, zinc, zinc oxide, ceramics, and tar are used. The addition of these various additives does not matter as long as the various properties of the moisture-curable coating composition of the present invention are not impaired.

As the curing catalyst suitably used in the moisture-curable coating composition of the present invention, a tertiary amine and a metal catalyst are used.

As the tertiary amine preferably added to the moisture-curable coating composition of the present invention, the tertiary amine used in the production of the modified polyisocyanate of the present invention can be preferably used. More preferably, triethylenediamine is used. These tertiary amines are used alone or as a mixture of two or more.

The addition amount of these tertiary amines is preferably 0.01 to 2 mol% in terms of amino groups per 1 mol of isocyanate groups of the modified polyisocyanate contained in the moisture-curable coating composition of the present invention. Preferably 0.0
An appropriate amount is 5 to 1 mol%, more preferably 0.05 to 0.5 mol%. 0.01 mol% of tertiary amine added
If it is less than 30, the curing reaction of a coating film or the like when the moisture-curable coating composition is used as a paint or the like is not sufficiently completed, and thus the curing of a coating film, a sealant, an adhesive layer, or the like obtained by the moisture-curable coating composition. It tends to cause defective and poor durability. In particular, when the moisture-curable coating composition is used as various top-coating paints, it is not preferable because it becomes a main factor of a decrease in gloss retention of the cured coating film, yellowing and chromaticity change. On the other hand, if the amount of the tertiary amine exceeds 2 mol%, when the moisture-curable coating composition is used as various top coatings, it causes yellowing and chromaticity change of the cured coating film, which is not preferable.

As the metal catalyst preferably added to the moisture-curable coating composition of the present invention, the metal catalyst used at the time of producing the modified polyisocyanate of the present invention can be preferably used. As a more preferably added metal catalyst, an organotin compound which has a catalytic action in an amino group generation reaction by an isocyanate group and water (moisture) in air and a reaction between an isocyanate group and an amino group is used. Specifically, the organotin compound used at the time of producing the modified polyisocyanate of the present invention can be preferably used. More preferably, organotin compounds such as tin octylate, dibutyltin dilaurate, and distaquinosan are used. These metal catalysts are used alone or as a mixture of two or more.

The amount of the metal catalyst is preferably 0.001 to 5% by weight, more preferably 0.01 to 2% by weight, based on the solid content of the modified polyisocyanate of the moisture-curable coating composition. , More preferably 0.01 to
0.4% by weight is an appropriate amount. The amount of metal catalyst added is 0.0
If the amount is less than 01% by weight, the curing reaction of the coating film or the like when the moisture-curable coating composition is used as a coating material or the like is not sufficiently completed, and thus the coating film, sealant, and adhesive layer obtained from the moisture-curable coating composition. It causes poor curing and poor durability. In particular, when the moisture-curable coating composition of the present invention is used as various overcoats, it is not preferable because it becomes a main factor of a decrease in gloss retention of the cured coating film, yellowing and chromaticity change. On the other hand, if the addition amount exceeds 5% by weight, when the moisture-curable coating composition of the present invention is used as various top coatings, it causes yellowing and chromaticity change of the cured coating film, which is not preferable.

Further, a tertiary amine and a metal catalyst are more preferably added to the moisture-curable coating composition of the present invention. The combined use of a tertiary amine and a metal catalyst makes it possible to reduce the absolute amount of a catalyst that sufficiently completes the curing reaction of a coating film, etc., and in the moisture-curable coating composition, yellowing and chromaticity of the cured coating film etc. Since the content of the catalyst which causes the change can be reduced, it is effective especially when used as various overcoats. These tertiary amines and metal catalysts may be the same or different from those added at the time of producing the modified polyisocyanate of the present invention.

The moisture-curable coating composition of the present invention preferably contains a coloring pigment, an extender or the like as a pigment.
As such a pigment, various paint pigments are used, for example,
"Revised New Edition Pigment Handbook" (edited by Japan Pigment Technology Association, 1989)
Pigment described on March 10, 2009) can be used. As the white pigment, titanium oxide, zinc white or the like is used. Titanium oxide is preferable because it has good weather resistance and is neutral. Further, among the titanium oxides, a rutile type titanium oxide having excellent weather resistance is preferably used. Also,
The surface of the titanium oxide may be surface-treated with an oxide of a metal such as silicon, aluminum, and zirconium. As the black pigment, carbon black or iron black is used. As the yellow pigment, there are yellow lead, red lead yellow, molybdenum orange, yellow iron oxide, loess, cadmium orange, cadmium yellow, zinc yellow, permanent orange, Hansa yellow, benzine yellows, benzine orange, indanthrene brilliant orange RK , Green gold, permanent yellow HR, titanium yellow, indanthrene brilliant orange GR, and the like. Red pigments include red iron oxide, iron oxide powder,
Cadmium Red, Cadmium Mercury Red, Copper Maroon, Permanent Red 4R, Para Red, Fire Red, Para Chlor Ortho Nitroaniline Red, Brilliant Fast Scarlet, Yoshu,
Pyrazolone Red, Vulcan Fastorbin B, Permanent Carmine FB, Fast Scarlet VD, Risor Red, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Toluidine Maroon, Permanent Bordeaux F2R, Bordeaux 1
0B, Bon Maroon Light, Bon Maroon Media, Alizarin Lake, Thio Indigo Red B, Thio Indigo Maroon, Permanent Red FGR, Watching Red Mn, Permanent Red BL, Chromophthal Bordeaux R, Monolight Fast Red YS, Shinkasha Red -Violet, quinacridone red and the like can be used. As the violet pigment, cobalt violet, mineral violet, purple bengal, carbazole dioxazine violet, quinacridone violet and the like can be used. As the blue pigment, navy blue, ultramarine blue, cobalt blue, cerulean blue, phthalocyanine blue, indanthrene blue BC and the like can be used. As the green pigment, chrome green, chromium oxide, zinc green, phthalocyanine green, polychlorobromide copper phthalocyanine and the like can be used.
Aluminum powder, bronze powder and the like can be used as the metal powder pigment. As extender pigments, carbonated lime powder,
Chalk, clay, gypsum, talc, asbestin, silica,
Magnesium carbonate, white carbon, barite powder, precipitated barium sulfate and the like can be used. As the kind of the pigment, both the organic pigment and the inorganic pigment are suitably used. In particular, in the case where the pigment is used for applications requiring weather resistance, for example, for various top coatings, the inorganic pigment is more preferably used. The timing of adding these various pigments is not particularly limited as long as the performance of the moisture-curable coating composition is not impaired, and does not hinder the present invention.

Further, in the moisture-curable coating composition of the present invention, the fluidity, additive dispersibility, coatability and filling property of the moisture-curable coating composition at the time of production and of the obtained moisture-curable coating composition are obtained. Alternatively, an organic solvent is preferably added in order to improve the uniformity of the cured coating film, sealant, adhesive layer and the like. By adding such an organic solvent, in the moisture-curable coating composition, coating, filling of a sealant, application of an adhesive, and the like can be facilitated. As such an organic solvent, an organic solvent having no active hydrogen is preferable in order to maintain the reactivity of the unreacted isocyanate group of the modified polyisocyanate contained in the moisture-curable coating composition,
Esters such as ethyl acetate, butyl acetate and cellosolve acetate; ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone; aromatic hydrocarbons such as benzene, toluene and xylene; and cyclic ethers such as tetrahydrofuran, dioxane and trioxane. It is preferably used. Among these organic solvents, acetone,
Cellosolve acetate, methyl ethyl ketone, methyl isobutyl ketone, toluene, xylene, tetrahydrofuran, dioxane and the like are more preferably used. In addition, these organic solvents are used not only alone but also as a mixture of two or more kinds, and may be the same or different from those added at the time of producing the modified polyisocyanate of the present invention. The timing of adding these various organic solvents is not particularly limited as long as the performance of the moisture-curable coating composition is not impaired, and does not hinder the present invention.

Further, various moisture-absorbing agents and antioxidants are added to the moisture-curable coating composition of the present invention so that the cured coating film, sealant, adhesive layer, etc. have weather resistance, light resistance, and oxidation resistance deterioration. Performance can be improved. Further, at the time of producing the modified polyisocyanate of the present invention, it is also possible to copolymerize a UV absorber or a monomer having an antioxidant property. As these various ultraviolet absorbers and antioxidants, benzophenone ultraviolet absorbers, phenylbenzoate ultraviolet absorbers, and hindered amino group antioxidants are used. These additives are preferably used in the range of 0.5 to 20% by weight based on the solid content of the modified polyisocyanate. If the amount is less than 0.5% by weight, the effect of addition is not recognized. If the amount exceeds 20% by weight, heat resistance, mechanical strength, and the like tend to decrease. In addition, these additives are used not only alone but also as a mixture of two or more kinds. The timing of adding these various ultraviolet absorbers and antioxidants is not particularly limited as long as the performance of the moisture-curable coating composition is not impaired, and does not hinder the present invention at all.

Further, the moisture-curable coating composition of the present invention may contain various additives and various improving agents in paints, sealants, adhesives, flooring agents, wall materials, waterproofing agents, etc. containing these as main components. Is also possible. Various surfactants can be used for the purpose of improving the surface smoothness, and specifically, silicon-based compounds, fluorine-based surfactants, organic surfactants, and the like can be used. Further, it is also preferable to add the modified polyisocyanate and the moisture-curable coating composition for the purpose of improving the degree of curing and maintaining and improving various physical properties such as a cured coating film, a sealant, and an adhesive layer, particularly durability and weather resistance.
As such additives, surfactants, stabilizers and the like are used. In addition, these additives are used not only alone but also as a mixture of two or more kinds. The timing of adding these various additives and various improvers is not particularly limited as long as the performance of the moisture-curable coating composition is not impaired, and does not hinder the present invention at all.

Further, the moisture-curable coating composition of the present invention comprises:
Various practical properties can be improved by various epoxy resins, melamine resins, amide resins and the like. Further, various catalysts other than the above tertiary amines and metal catalysts may be used in combination for the purpose of accelerating curing and curing at low temperature. Specific examples of these catalysts include various organic acids and their acid anhydrides, nitrogen-containing organic compounds, various metal complex compounds, or metal alkoxides, and various salts of alkali metal organic carboxylate and carbonate. Are used. These catalysts can be used not only alone but also as a mixture of two or more kinds. The timing of adding these resins and catalysts is not particularly limited as long as the performance of the moisture-curable coating composition is not impaired, and does not hinder the present invention.

[0051] These additives may be used in combination with the moisture-curable coating composition of the present invention and the paints, sealants and adhesives obtained using the moisture-curable coating composition of the present invention. Various practical characteristics can be improved depending on the application to which the resin composition is applied.

The moisture-curable coating composition of the present invention comprises:
It can be used as a sealant, adhesive, flooring agent, wall agent, waterproofing agent, putty, resin modifier, lining agent, etc., but it can be suitably used as a paint, and it can be used as a top coat, middle coat, or undercoat In particular, when used as a top coat paint, more specifically, as a single coat or a top coat of two or more layers, its performance can be sufficiently exhibited. Furthermore, the performance can be sufficiently exhibited as a topcoating paint for applications requiring a high gloss value on the surface of the coating film. As a coating method, a commonly used coating method such as brush coating, dip coating, roll coating, spray coating, spin coating, and flow coating can be easily used. In application, various pretreatments may be performed for the purpose of improving cleaning, adhesion, water resistance, and the like. As a pre-treatment for these purposes, a normal kelenium treatment is preferably used, but an activation gas treatment, a chemical treatment, an ultraviolet treatment or the like is also possible. It is sufficiently possible to carry out these pretreatments continuously or stepwise in combination. Further, it is sufficiently possible to carry out these pretreatments continuously or stepwise in combination.

Further, a coating system using the moisture-curable coating composition of the present invention as a top coating has excellent durability such as weather resistance and rust prevention, so that repair coating can be unnecessary for a long period of time. In this case, as the intermediate coating, a moisture-curable urethane urea coating, an epoxy resin intermediate coating, an MIO (mica-like iron oxide) coating, or the like is used, and a moisture-curing urethane urea coating is preferable. Curable urethane urea coatings are preferred. As the undercoat paint, a zinc-containing moisture-curable urethane urea paint, an epoxy resin undercoat paint, a zinc paint, etc. are used, and a zinc-containing moisture-curable urethane urea paint is preferable. Urea paints are preferred.

[0054]

[Evaluation method of characteristics] Various characteristics were measured as follows.

(A) Weather resistance (gloss retention, color difference) The moisture-curable coating composition of the present invention was cured on a cold rolled steel sheet (SPCC-SD) having a thickness of 40 μm.
Was applied and cured sufficiently at room temperature to obtain a test plate. About the obtained test plate with a coating film, use Sunshine Weather O Meter (Suga Test Machine Co., Ltd.)
), And the surface gloss value and chromaticity before the test and after the 1000-hour elapsed test are shown in (b) below.
The gloss retention and the color difference were measured by the method described in (c).

(B) Surface Gloss Value, Gloss Retention According to JIS Z8741 (specular gloss measurement method), portable gloss meter GM manufactured by Niri Shoji Co., Ltd.
The specular gloss value was measured using X-202, and it was set as the surface gloss value. The gloss retention was calculated as a percentage of the surface gloss value after the exposure test to the surface gloss value before the exposure test.

(C) Chromaticity and color difference L ^* a ^* specified in JIS Z 8809 (color difference display method)
The chromaticity E of the b ^* coordinate system = (L ^* , a ^* , b ^* ) was defined as the chromaticity of the present invention. Also, the color difference ΔE = E ₂ −E ₁ of the present invention is
For each chromaticity defined by the above-mentioned criterion, the distance on the L ^* a ^* b ^* coordinate system, that is, ΔE = [(L ₂ −L ₁ ) ² + (a ₂ −a ₁ ) ² + (b ₂ −b ₁ )
² ] ^1/2, and all were measured using an SM computer manufactured by Suga Test Instruments Co., Ltd.

(D) Chemical resistance (alkali resistance and acid resistance) On a cold-rolled steel sheet (SPCC-SB) treated with kelenium,
Coating of zinc-containing moisture-curable urethane urea paint (commercially available) and MIO-containing moisture-curable urethane urea intermediate coating (commercially available) at intervals of one day so that the film thickness after curing becomes 100 μm. Further, the moisture-curable coating composition of the present invention was applied so that the film thickness after curing became 40 μm, and the composition was sufficiently cured to obtain a test plate.

Regarding the obtained test plate, JIS K5
According to 658 (polyurethane resin paint for steel structure), alkali resistance is JIS K of 20 ± 1 ° C.
Use a 5 w / v% aqueous sodium hydroxide solution adjusted using sodium hydroxide specified in 8576, and use a 5 w / v% aqueous sulfuric acid solution adjusted using sulfuric acid specified in JIS K 8951 at 20 ± 1 ° C for acid resistance. (B) changes in surface appearance after pulling up, gently rinsing the coating film surface with water, and allowing it to stand for 2 hours.
Evaluation was made by the gloss retention measured in the same manner as in the item.

(E) Solvent resistance and xylene rubbing resistance The moisture-curable coating composition of the present invention having a cured film thickness of 40 μm on a cold-rolled steel sheet (SPCC-SD) treated with kelenium.
And left overnight at room temperature to obtain a test plate. The surface of the obtained test plate was rubbed with gauze impregnated with xylene, and the gloss change at that time was visually evaluated.

[0061]

EXAMPLES Hereinafter, the present invention will be described more specifically based on examples.

Example 1 250 g of isophorone diisocyanate, 0.25 g of dibutyltin dilaurate, 2.5 g of triethylenediamine
g and 108 g of xylene were mixed at room temperature to prepare a uniform solution (hereinafter referred to as solution (I)). Meanwhile, polytetramethylene glycol diol (Sanyo Chemical Industries, Ltd.)
Manufactured and trade name PTMG-1000; number average molecular weight 100
192 g of 0) and 26 g of trimethylolpropane were dissolved in 93 g of xylene to prepare a uniform solution (hereinafter referred to as solution (II)). The resulting solution (I) was stirred for 90
C., and the solution (II) was continuously dropped at a rate of 100 g / hour. After completion of the dropwise addition, the mixture is aged at 90 ° C. for 5 hours under stirring to complete the urethanization reaction, and to obtain a moisture-curable resin composition containing a modified polyisocyanate having an unreacted isocyanate group as a main component (hereinafter referred to as “moisture”). Curable resin composition (A)) was obtained.

Similarly, isophorone diisocyanate 25
0 g, dibutyltin dilaurate 0.25 g, triethylenediamine 2.5 g, and xylene 108 g were mixed at room temperature to prepare a uniform solution (hereinafter referred to as solution (III)). On the other hand, 192 g of polycaprolactone diol (trade name “Placcel” 210; manufactured by Daicel Chemical Industries, Ltd .; number average molecular weight 1000) and polycaprolactone triol (trade name “Placcel” 303, manufactured by Daicel Chemical Industries, Ltd.) 92 g of xylene (average molecular weight: 300) was dissolved in 122 g of xylene to prepare a uniform solution (hereinafter referred to as solution (IV)). The resulting solution (III) is stirred for 90
C., and the solution (IV) was continuously dropped at a rate of 100 g / hour. After completion of the dropwise addition, the mixture is aged at 90 ° C. for 5 hours under stirring to complete the urethanization reaction, and to obtain a moisture-curable resin composition containing a modified polyisocyanate having an unreacted isocyanate group as a main component (hereinafter referred to as “moisture”). Curable resin composition (B)) was obtained.

Then, 240 g of the obtained moisture-curable resin composition (A) and 160 g of the moisture-curable resin composition (B)
Of titanium oxide (D-Pont, R-96)
0) 220 g, dibutyltin dilaurate 0.1 g, triethylene diamine 0.5 g, dehydrating agent (trimethyl orthoformate) 20 g, thickener (calcium carbonate) 20 g, and methyl isobutyl ketone 340 g were thoroughly mixed with a homomixer to obtain moisture. A curable coating composition was obtained.

The initial gloss value of the coating film obtained from the obtained moisture-curable coating composition was 95%, and the xylene rubbing resistance was good. A coating film of this composition was subjected to a weather resistance test (1000 hours).
% And color difference were 0.6. Further, the shape of the coating film surface was sufficiently smooth without much difference from that immediately after the formation of the coating film. Regarding the chemical resistance of this coated steel sheet, there was no change in the appearance of the coated film before and after the test for both alkali resistance and acid resistance, and the gloss retention was 85%.
Met.

Example 2 For the mixture of the moisture-curable resin composition (A) and the moisture-curable resin composition (B) of Example 1, 280 g of the moisture-curable resin composition (A) and the moisture-curable resin composition (B) 120
The same operation as above was carried out except that the mixture was obtained as a mixture of g, to obtain a moisture-curable coating composition.

The initial gloss value of the coating film obtained from the obtained moisture-curable coating composition was 96%, and the xylene rubbing resistance was good. A coating film of this composition was subjected to a weather resistance test (1000 hours).
% And color difference were 0.8. Further, the shape of the coating film surface was sufficiently smooth without much difference from that immediately after the formation of the coating film. Regarding the chemical resistance of the coated steel sheet, there was no change in the appearance of the coated film before and after the test for both alkali resistance and acid resistance, and the gloss retention was 84%.
Met.

Example 3 For the mixture of the moisture-curable resin composition (A) and the moisture-curable resin composition (B) of Example 1, 200 g of the moisture-curable resin composition (A) and the moisture-curable resin composition (B) 200
The same operation as above was carried out except that the mixture was obtained as a mixture of g, to obtain a moisture-curable coating composition.

The initial gloss value of the coating film obtained from the obtained moisture-curable coating composition was 94%, and the xylene rubbing resistance was good. A coating film of this composition was subjected to a weather resistance test (1000 hours). As a result, the gloss retention was 81.
% And color difference were 0.6. Further, the shape of the coating film surface was sufficiently smooth without much difference from that immediately after the formation of the coating film. Regarding the chemical resistance of the coated steel sheet, there was no change in the appearance of the coated film before and after the test for both alkali resistance and acid resistance, and the gloss retention was 84%.
Met.

Example 4 The moisture-curable resin composition (A) of Example 1 was prepared using polytetramethylene glycol-modified polyisocyanate (commercially available, 2.5 functional groups, 5.1% NCO value, 70% solids by weight).
The moisture-curable coating composition was obtained by performing the same operation except that the composition was changed to.

The initial gloss value of the coating film obtained from the obtained moisture-curable coating composition was 95%, and the xylene rubbing resistance was good. A coating film of this composition was subjected to a weather resistance test (1000 hours).
% And color difference were 0.7. Further, the shape of the coating film surface was sufficiently smooth without much difference from that immediately after the formation of the coating film. Regarding the chemical resistance of this coated steel sheet, there was no change in the appearance of the coated film before and after the test for both alkali resistance and acid resistance, and the gloss retention was 81%.
Met.

Example 5 The polytetramethylene glycol-modified polyisocyanate of Example 4 (commercially available product, having 2.5 functional groups, NCO value 5.1)
%, Solid content 70% by weight) and the moisture-curable resin composition (B)
Was performed in the same manner, except that 280 g of the polytetramethylene glycol-modified polyisocyanate and 120 g of the moisture-curable resin composition (B) were used to obtain a moisture-curable coating composition.

The initial gloss value of the coating film obtained from the obtained moisture-curable coating composition was 94%, and the xylene rubbing resistance was good. A coating film of this composition was subjected to a weather resistance test (1000 hours). As a result, the gloss retention was 81.
% And color difference were 0.7. Further, the shape of the coating film surface was sufficiently smooth without much difference from that immediately after the formation of the coating film. Regarding the chemical resistance of this coated steel sheet, there is no change in the appearance of the coated film before and after the test for both alkali resistance and acid resistance, and the gloss retention is 80%.
Met.

Example 6 With respect to the mixture of the polytetramethylene glycol-modified polyisocyanate and the moisture-curable resin composition (B) of Example 4, 200 g of the polytetramethylene glycol-modified polyisocyanate and 200 g of the moisture-curable resin composition (B)
A moisture-curable coating composition was obtained by performing the same operation except that the mixture was used.

The initial gloss value of the coating film obtained from the obtained moisture-curable coating composition was 94%, and the xylene rubbing resistance was good. A coating film of this composition was subjected to a weather resistance test (1000 hours). As a result, the gloss retention was 81.
% And color difference were 0.6. Further, the shape of the coating film surface was sufficiently smooth without much difference from that immediately after the formation of the coating film. Regarding the chemical resistance of the coated steel sheet, there was no change in the appearance of the coated film before and after the test for both alkali resistance and acid resistance, and the gloss retention was 82%.
Met.

Comparative Example 1 A moisture-curable coating composition was prepared in the same manner as in Example 1 except that the moisture-curable resin composition (B) was not added and only 400 g of the moisture-curable resin composition (A) was used. I got something.

The initial gloss value of the coating film obtained from the obtained moisture-curable coating composition was 95%, and the xylene rubbing resistance was good. However, as a result of performing a weather resistance test (1000 hours) on a coating film using this composition, the gloss retention was 36%, and the color difference was 4.0. Further, the shape of the coating film surface was sufficiently smooth without much difference from that immediately after the formation of the coating film.

However, the chemical resistance of the coated steel sheet is as follows:
Regarding the alkali resistance, there was no change in the appearance of the coating film before and after the test, and the gloss retention was as good as 84%. However, as for the acid resistance, many blisters occurred on the coating surface after the test, and the gloss retention was 15%. %Met.

Comparative Example 2 For the mixture of the moisture-curable resin composition (A) and the moisture-curable resin composition (B) of Example 1, 360 g of the moisture-curable resin composition (A) and the moisture-curable resin composition (B) 40 g
A moisture-curable coating composition was obtained by performing the same operation except that the mixture was used.

The initial gloss value of the coating film obtained from the obtained moisture-curable coating composition was 94%, and the xylene rubbing resistance was good. However, as a result of performing a weather resistance test (1000 hours) on the coating film using this composition, the gloss retention was 40% and the color difference was 3.0. Further, the shape of the coating film surface was sufficiently smooth without much difference from that immediately after the formation of the coating film.

However, the chemical resistance of this coated steel sheet is as follows:
Regarding the alkali resistance, there was no change in the appearance of the coating film before and after the test, and the gloss retention was as good as 83%. However, as for the acid resistance, many blisters occurred on the coating surface after the test, and the gloss retention was 20%. %Met.

Comparative Example 3 With respect to the mixture of the moisture-curable resin composition (A) and the moisture-curable resin composition (B) of Example 1, 80 g of the moisture-curable resin composition (A) and the moisture-curable resin composition (B) 320 g
A moisture-curable coating composition was obtained by performing the same operation except that the mixture was used.

The initial gloss value of the coating film obtained from the obtained moisture-curable coating composition was 94%, and the xylene rubbing resistance was good. A coating film of this composition was subjected to a weather resistance test (1000 hours). As a result, the gloss retention was 81.
% And color difference were 0.6. Further, the shape of the coating film surface was sufficiently smooth without much difference from that immediately after the formation of the coating film.

However, the chemical resistance of this coated steel sheet is as follows:
With respect to acid resistance, there was no change in the appearance of the coating film before and after the test, and the gloss retention was as good as 84%. Regarding alkali resistance, there was no change in the appearance of the coating film before and after the test, but the gloss retention was 40%. %Met.

Comparative Example 4 The same operation was carried out except that the moisture-curable resin composition (A) was not added and only 400 g of the moisture-curable resin composition (B) was used. A composition was obtained.

The initial gloss value of the coating film obtained from the obtained moisture-curable coating composition was 94%, and the xylene rubbing resistance was good. A coating film of this composition was subjected to a weather resistance test (1000 hours).
% And color difference were 0.7. Further, the shape of the coating film surface was sufficiently smooth without much difference from that immediately after the formation of the coating film.

However, the chemical resistance of this coated steel sheet is as follows:
With respect to acid resistance, there was no change in the appearance of the coating film before and after the test, and the gloss retention was as good as 84%. Regarding alkali resistance, there was no change in the appearance of the coating film before and after the test, but the gloss retention was 35. %Met.

Comparative Example 5 Instead of the moisture-curable resin composition (A) of Comparative Example 1, a polytetramethylene glycol-modified polyisocyanate (commercially available, having 2.5 functional groups, an NCO value of 5.1%, and a solid content of 70%)
(% By weight) to obtain a moisture-curable coating composition.

The initial gloss value of the coating film obtained from the obtained moisture-curable coating composition was 94%, and the xylene rubbing resistance was good. However, as a result of performing a weather resistance test (1000 hours) on a coating film using this composition, the gloss retention was 45%, and the color difference was 3.5. Further, the shape of the coating film surface was sufficiently smooth without much difference from that immediately after the formation of the coating film.

However, the chemical resistance of this coated steel sheet is as follows:
Regarding alkali resistance, there was no change in the appearance of the coating film before and after the test, and the gloss retention was as good as 84%. Regarding acid resistance, there was no change in the appearance of the coating film before and after the test, but the gloss retention was 30%. %Met.

Comparative Example 6 Instead of the moisture-curable resin composition (A) of Comparative Example 2, a polytetramethylene glycol-modified polyisocyanate (commercial product, functional group number 2.5, NCO value 5.1%, solid content 70
(% By weight) to obtain a moisture-curable coating composition.

The initial gloss value of the coating film obtained from the obtained moisture-curable coating composition was 96%, and the xylene rubbing resistance was good. However, as a result of performing a weather resistance test (1000 hours) on the coating film of this composition, the gloss retention was 36%, and the color difference was 3.3. Further, the shape of the coating film surface was sufficiently smooth without much difference from that immediately after the formation of the coating film.

However, the chemical resistance of this coated steel sheet is as follows:
Regarding alkali resistance, there was no change in the appearance of the coating film before and after the test, and the gloss retention was as good as 86%. Regarding acid resistance, there was no change in the appearance of the coating film before and after the test, but the gloss retention was 29. %Met.

Comparative Example 7 Instead of the moisture-curable resin composition (A) of Comparative Example 3, a polytetramethylene glycol-modified polyisocyanate (commercially available, having 2.5 functional groups, NCO value 5.1%, solid content 70)
(% By weight) to obtain a moisture-curable coating composition.

The initial gloss value of the coating film obtained from the obtained moisture-curable coating composition was 96%, and the xylene rubbing resistance was good. A coating film of this composition was subjected to a weather resistance test (1000 hours).
% And color difference were 0.7. Further, the shape of the coating film surface was sufficiently smooth without much difference from that immediately after the formation of the coating film.

However, the chemical resistance of this coated steel sheet is as follows:
Regarding the acid resistance, there was no change in the appearance of the coating film before and after the test, and the gloss retention was as good as 83%. %Met.

[0097]

According to the present invention, weather resistance, light resistance, yellowing resistance,
Polyester polyol-modified polyisocyanate obtained by modifying polyester polyol excellent in acid resistance and solvent resistance, and polyether polyol modified by modifying polyether polyol excellent in water resistance, alkali resistance, solvent resistance, etc. By using polyisocyanate together and containing both as main components, weather resistance, light resistance,
Moisture-curable paint compositions that can provide paints, coatings, sealants, adhesives, etc. that are excellent in both durability such as yellowing resistance and chemical resistance such as acid resistance, alkali resistance, and solvent resistance provide.

Claims (7)

[Claims] 1. In a coating film having a surface gloss value of 70% or more after curing, when a 5 w / v% aqueous solution of sodium hydroxide and a 5 w / v% aqueous solution of sulfuric acid adhere to the surface, 168 hours after application of the solution A moisture-curable coating composition having a surface gloss retention of at least 70%. 2. In a coating film having a surface gloss value of 70% or more after curing, the retention of the surface gloss value after treatment for 1000 hours with a Sunshine Weather O Meter is 70% or more, and the color difference (ΔE value). The moisture-curable coating composition according to claim 1, wherein is less than or equal to 2. 3. A modified polyisocyanate obtained by reacting a polyol and a polyisocyanate, wherein the modified polyisocyanate is obtained from a polyether polyol and a polyisocyanate, and the modified polyisocyanate is obtained from a polyester polyol and a polyisocyanate. A moisture-curable coating composition comprising the polyester polyol-modified polyisocyanate obtained. 4. The moisture-curable coating composition according to claim 3, wherein the weight ratio between the polyether polyol-modified polyisocyanate and the polyester polyol-modified polyisocyanate is 80/20 to 30/70. 5. The moisture-curable coating composition according to claim 3, wherein the weight ratio of the polyether polyol-modified polyisocyanate to the polyester polyol-modified polyisocyanate is from 70/30 to 50/50. 6. The polyester polyol according to claim 3, wherein the polyester polyol is a polycaprolactone polyol.
The moisture-curable coating composition according to any one of the above. 7. The moisture-curable coating composition according to claim 3, wherein the polyether polyol is a polypropylene glycol polyol and / or a polytetramethylene glycol polyol.