JPH04226965A - Polyisocyanato-isocyanurate and its production and use - Google Patents

Abstract

PURPOSE:To obtain the subject compound, improved in curability and drying properties and useful as a resin for urethane coatings. CONSTITUTION:A mixture containing two or more polyisocyanato-isocyanurates expressed by formula I {R1 to R3 are 2-12C alkylene or formula II [(k) and (h) are 0-2; (j) and (m) are 1-5]; (n) is 1-5}. compound expressed by formula I is obtained by reacting a straight-chain aliphatic diisocyanate (e.g. hexamethylene diisocyanate) expressed by formula III (R4 is 2-12C alkylene) with a polycyclic aliphatic diisocyanate, e.g. 2,6- diisocyanatomethylbicyclo[2.2.1]heptane expressed by formula IV. The aforementioned compound can be used as a curing agent to prepare a resin for nonyellowing type urethane coatings.

Description

Description: TECHNICAL FIELD The present invention relates to a novel polyisocyanato-isocyanurate, a method for producing the same, and uses thereof. More specifically, the present invention relates to a polyisocyanato-isocyanurate with a new structure, a method for producing the same, and the use of this polyisocyanato-isocyanurate in curing agents, resins, and paints. BACKGROUND OF THE INVENTION Polyisocyanato-isocyanurate compounds in which part of the isocyanate groups of organic diisocyanates are trimerized and methods for producing the same are known from many publications [for example, J.D. Naughty. Saunders and K.
C. Frisch: Polyurethane, Chemistry and Technology (1962) P. 94 (
J. H. Saunders and K. C. Fri
sh:Polyuretanes, Chemistry
y and Technology (1962) P.
94)]. These polyisocyanato-isocyanurate compounds are widely used as raw materials for resins, foams, paints, films, adhesives, and the like. For example, a nurate compound of hexamethylene diisocyanate represented by the following formula (a) [Image Omitted] is widely used as a resin for two-component urethane paints and as a raw material thereof. [0003] Two-component urethane paint resins have already been widely used as various paints, using isocyanate compounds as curing agents and polyol compounds as main ingredients. However, these have been developed with better performance. For example, the most typical general-purpose curing type uses urethane-type polyisocyanate or polyisocyanurate-type isocyanate derived from tolylene diisocyanate as a curing agent, and uses alkyd resin, polyester polyol, acrylic polyol, or epoxy polyol as the main ingredient. Two-component urethane paint resins are used in furniture, woodworking paints, and corrosion-resistant paints called tar urethane paints. However, although urethane paints using tolylene diisocyanate have high reactivity and excellent drying properties, they have extremely poor weather resistance. Therefore, for the purpose of improving weather resistance, polyisocyanates derived from aliphatic or alicyclic compounds such as hexamethylene diisocyanate, isophorone diisocyanate, or 4,4'-dicyclohexamethylene diisocyanate are used. A two-component polyurethane paint resin was devised that uses an acrylic polyol or a polyester polyol as a hardening agent. As such a resin for two-component polyurethane coatings, aliphatic polyisocyanates such as hexamethylene diisocyanate (hereinafter abbreviated as HDI) are used.
Urethane type polyisocyanates derived from biuret type polyisocyanates (e.g. USP 3,9
03,127), isocyanurate-type polyisocyanates (e.g. USP 3,487,080, USP 4
, 412,073), and also alicyclic polyisocyanates, such as isophorone diisocyanate (hereinafter referred to as I
(abbreviated as PDI) (for example DE 1,962,808)
, isocyanurate type polyisocyanates (e.g.
USP 3,919,218) etc. are known. These materials have excellent characteristics such as weather resistance, flexibility, and abrasion resistance, and have established a firm position in the fields of automobile repair, architectural exteriors, etc., for example. However, these aliphatic or cycloaliphatic polyisocyanates have poor drying properties, so two-component urethane paints using these as curing agents require long periods of time to sufficiently crosslink and form a tough coating film. Forced drying methods had to be used, either by letting it stand or by baking. However, due to poor heat resistance, yellowing is inevitable during baking, resulting in decreased gloss. In addition, polyisocyanato-isocyanurates derived from HDI have poor compatibility with polyols, especially acrylic polyols, and two-component urethane paints using these as curing agents and main ingredients have poor gloss, sharpness, It has the drawbacks that leveling properties are reduced and the main ingredients that can be used are limited. Furthermore, polyisocyanate derived from IPDI has low reactivity because the isocyanate groups involved in the reaction are bonded to secondary carbons, and two-component urethane paints using this as a curing agent have poor drying properties. It had a very bad drawback. Furthermore, polyisocyanato-isocyanurates obtained from mixtures of HDI and IPDI have been proposed (USP 4,419,513). However, I
In PDI, one of the two isocyanate groups has high reactivity because it is bonded to a primary carbon, and the other isocyanate group has low reactivity because it is bonded to a secondary carbon. . When such IPDI is used in a cyclic trimerization reaction, highly reactive isocyanate groups react preferentially,
Less reactive isocyanate groups remain. Therefore, HD
Polyisocyanato-isocyanurate obtained by trimerizing a mixture of I and IPDI has the drawback of low reactivity and poor drying properties when used for urethane coatings. Even if a mixture with a high HDI content is trimerized to improve drying properties, the resulting polyisocyanato-isocyanurate has the disadvantage of yellowing when baked at high temperatures for use in urethane paints. . Therefore, there has been a strong desire to develop a resin for two-component urethane paints that has good weather resistance and excellent drying properties. Furthermore, so-called blocked isocyanate, which is obtained by blocking the isocyanate groups of an isocyanate compound with a blocking agent, is used as a curing agent in polyester powder coatings whose main ingredient is polyester resin. In particular, blocked isocyanates derived from IPDI are widely used as polyester powder coatings based on polyester resins, for example, for precoat metal applications. However, when a blocked isocyanate derived from isophorone diisocyanate is used as a curing agent, a baking temperature of 200°C or higher is usually required, and even if a metal catalyst such as dibutyltin dilaurylate is used in combination, the baking temperature is 180°C or higher. was necessary. Therefore, a curing agent for polyester powder coatings with excellent low-temperature curability and weather resistance has been desired. One object of the present invention is to provide a novel polyisocyanate useful for urethane coating resins and other uses.
An object of the present invention is to provide isocyanurates and mixtures thereof. The second object of the present invention is to provide a novel polyisocyanate
An object of the present invention is to provide a method for producing isocyanurates and mixtures thereof. A third object of the present invention is to provide a urethane coating resin with improved curability and drying properties using a novel polyisocyanato-isocyanurate mixture, and a coating composition containing this resin. A fourth object of the present invention is to provide a curing agent for polyester powder coatings with excellent low-temperature curability and a polyester powder coating composition containing this curing agent. In order to achieve the above object, the present inventors studied various isocyanurate group-containing polyisocyanates of aliphatic diisocyanates. As a result, the aliphatic diisocyanate represented by the general formula (3) and the general formula (4
) When polyisocyanato-isocyanurate obtained from a mixture of polycyclic aliphatic diisocyanates represented by and has excellent curing and drying properties. In particular, 2,5- or 2,6-diisocyanatomethylbicyclo[2,2,1]heptane and mixtures thereof, or their It was discovered that blocked isocyanate, in which a modified NCO group is blocked with a blocking agent having one or more active hydrogen atoms in the molecule, has an excellent effect as a curing agent for polyester powder coatings, and the present invention was completed. Ta. That is, the present invention provides general formula (1)
] [In the formula, R1, R2 and R3 have 2 to 1 carbon atoms
2 or an alkylene group of formula (2)
(represents an integer of 1 to 5), which may be the same or different from each other, n represents an integer of 1 to 5]
It is a polyisocyanato-isocyanurate mixture containing two or more kinds of polyisocyanato-isocyanurates represented by
At least one of 2 and R3 is a group represented by formula (2), and the remainder is an alkylene group having 2 to 12 carbon atoms, which is substantially a single polyisocyanato-isocyanurate; Nato-isocyanurates or mixtures thereof (hereinafter, unless otherwise specified, substantially single polyisocyanato-isocyanurates or mixtures of polyisocyanato-isocyanurates are simply referred to as polyisocyanato-isocyanurates) are represented by the general formula ( 3) O
CN-R4-NCO
(3) (wherein, R4 has 2 to 2 carbon atoms
12 alkylene groups) and a linear aliphatic diisocyanate represented by the general formula (4) [Chemical formula 11] (where k is 0 to 2, j and m are 1 to 5, and h is 0 to 2
This is a method of producing a polycyclic aliphatic diisocyanate expressed by A coating composition containing a resin curing agent in which the isocyanate groups of the polyisocyanato-isocyanurate are blocked with a blocking agent, and furthermore, particularly a 2,5- or 2,6-diisocyanate. Methylbicyclo [2,2,
1] Heptane, a mixture thereof, or a modified product thereof;
This is a curing agent for powder coatings containing blocked isocyanate synthesized from a blocking agent having one or more active hydrogen atoms in the molecule. [0011] Means for Solving the Problems The polyisocyanato-isocyanurate or the polyisocyanato-isocyanurate mixture which is a substantially simple substance of the present invention has the general formula (
1) It is included in the polyisocyanato-isocyanurate represented by, and more specifically, the polyisocyanato-isocyanurate mixture is one in which R1, R2, and R3 are the same or different in the general formula (1), n is 1
It is a mixture containing two or more kinds of polyisocyanato-isocyanurates represented by the general formula (1) which is any one of 5 to 5, and the polyisocyanato-isocyanurate which is substantially single is , in general formula (1), R1
, R2 and R3 is represented by formula (2) [
Chemical formula 12] (wherein k is 0-2, j and m are 1-5, h is 0-2
), with the remainder having 2 to 2 carbon atoms.
It is a polyisocyanato-isocyanurate having a substantially single structure consisting of 12 alkylene groups. Such a polyisocyanato-isocyanurate mixture of the present invention comprises a linear aliphatic diisocyanate represented by the general formula (3) and a linear aliphatic diisocyanate represented by the general formula (4) in the presence of a trimerization catalyst. It is obtained by trimerizing a mixture of polycyclic aliphatic diisocyanate and polycyclic aliphatic diisocyanate under predetermined conditions. That is, in the production method of the present invention, the molar ratio of the linear aliphatic diisocyanate represented by the general formula (3) and the polycyclic aliphatic diisocyanate represented by the general formula (4) is about 1:
A mixture of 11 to 11:1 is trimerized with a portion of the isocyanate groups to reduce approximately 20 of the isocyanate groups originally present.
When ~50% is trimerized, a catalyst poison is immediately added to deactivate the trimerization catalyst to stop the trimerization reaction, and if necessary, unreacted diisocyanate is removed by thin film distillation. . The linear aliphatic diisocyanate used in the production method of the present invention has the general formula (3) OCN-R4-NCO
(3) (wherein R4 represents an alkylene group having 2 to 12 carbon atoms), specifically, 1,2-diisocyanatoethane, 1,3-diisocyanatopropane, 1, 4
-diisocyanatobutane, 1,5-diisocyanatopentane, 1,6-diisocyanatohexane, 1,7-
Diisocyanatoheptane, 1,8-diisocyanatooctane, 1,9-diisocyanatononane, 1,10-
Examples include diisocyanatodecane, 1,11-diisocyanatooundecane, 1,12-diisocyanatododecane, and the like. Among these, 1,6-diisocyanatohexane (
Hexamethylene diisocyanate (HDI). Further, the polycyclic aliphatic diisocyanate used in this method has the general formula (4): 0-2
where k=0 means no crosslinking). Specifically, when k=0 and h=0, 1,3-di(isocyanatomethyl)-cyclohexane,
1,4-di(isocyanatomethyl)-cyclohexane,
1,3-di(isocyanatoethyl)-cyclohexane,
1,4-di(isocyanatoethyl)-cyclohexane,
1-isocyanatomethyl-3(4)-isocyanatoethyl-cyclohexane, 1-isocyanatomethyl-3(4)-isocyanatopropyl-cyclohexane, 1-isocyanatomethyl-3(4)-isocyanatobutyl-cyclohexane , 1-isocyanatomethyl-3(4)-isocyanatopentyl-cyclohexane, 1-isocyanatoethyl-3(4)-isocyanatopropyl-cyclohexane, 1-isocyanatoethyl-3(4)-isocyanatobutyl- Examples include cyclohexane, 1-isocyanatomethyl-3(4)-isocyanatopentyl-cyclohexane, and the like. Assuming that k=0 and h=1, 3(4),
7(8)-di(isocyanatomethyl)bicyclo[4
,3,01,6]nonane, 3(4)-isocyanatomethyl-7(8)-isocyanatoethylbicyclo[4,3,01,6]nonane, 3
(4)-isocyanatoethyl-7(8)-isocyanatomethylbicyclo[4,3,01,6]nonane, 3(
4)-isocyanatomethyl-7(8)-isocyanatopropylbicyclo[4,3,01,6]nonane, 3(
4)-isocyanatopropyl-7(8)-isocyanatomethylbicyclo[4,3,01,6]nonane, 3(
4)-isocyanatomethyl-7(8)-isocyanatobutylbicyclo[4,3,01,6]nonane, 3(4
)-isocyanatobutyl-7(8)-isocyanatomethylbicyclo[4,3,01,6]nonane, 3(4)
- Isocyanatomethyl-7(8)-isocyanatopentylbicyclo[4,3,01,6]nonane, 3(4)
- Isocyanatopentyl-7(8)-isocyanatomethylbicyclo[4,3,01,6]nonane, 3(4)
,7(8)-di(isocyanatoethyl)bicyclo[
4,3,01,6]nonane, 3(4)-isocyanatoethyl-7(8)-isocyanatopropylbicyclo[4,3,01,6]nonane,
3(4)-isocyanatopropyl-7(8)-isocyanatoethylbicyclo[4,3,01,6]nonane,
3(4)-isocyanatoethyl-7(8)-isocyanatobutylbicyclo[4,3,01,6]nonane, 3
(4)-isocyanatobutyl-7(8)-isocyanatoethylbicyclo[4,3,01,6]nonane, 3(
4)-isocyanatoethyl-7(8)-isocyanatopentylbicyclo[4,3,01,6]nonane, 3(
4)-isocyanatopentyl-7(8)-isocyanatoethylbicyclo[4,3,01,6]nonane, and the like. Assuming that k=1 and h=0, 2,5(6
)-di(isocyanatomethyl)bicyclo[2,2,1
]Heptane, 2-isocyanatomethyl-5(6)-isocyanatoethylbicyclo[2,2,1]heptane, 2
-isocyanatomethyl-5(6)-isocyanatopropylbicyclo[2,2,1]heptane, 2-isocyanatomethyl-5(6)-isocyanatobutylbicyclo[2,2,1]heptane, 2-isocy Natomethyl-5(6)-isocyanatopentylbicyclo[2,2,1]heptane, 2,5(6)-di(isocyanatoethyl)bicyclo[
2,2,1]heptane, 2-isocyanatoethyl-5(
6)-isocyanatopropylbicyclo[2,2,1]
Heptane, 2-isocyanatoethyl-5(6)-isocyanatobutylbicyclo[2,2,1]heptane, 2-isocyanatoethyl-5(6)-pentylbicyclo[
2,2,1]heptane and the like. Assuming that k=2 and h=0, 2,5(6
)-di(isocyanatomethyl)bicyclo[2,2,2
] Octane, 2-isocyanatomethyl-5(6)-isocyanatoethylbicyclo[2,2,2]octane, 2
-isocyanatomethyl-5(6)-isocyanatopropylbicyclo[2,2,2]octane, 2-isocyanatomethyl-5(6)-isocyanatobutylbicyclo[2,2,2]octane, 2-isocya Natomethyl-5(6)-isocyanatopentylbicyclo[2,2,2]octane, 2,5(6)-di(isocyanatoethyl)bicyclo[2
,2,2]octane,2-isocyanatoethyl-5(
6)-isocyanatopropylbicyclo[2,2,2]
Octane, 2-isocyanatoethyl-5(6)-isocyanatobutylbicyclo[2,2,2]octane, 2-isocyanatoethyl-5(6)-isocyanatopentylbicyclo[2,2,2]octane, etc. can be mentioned. Assuming that k=1 and h=1, 3(4),
8(9)-di(isocyanatomethyl)tricyclo[5,
2,1,02,6]decane, 3(4)-isocyanatomethyl-8(9)-isocyanatoethyltricyclo[5,2,1,02,6]decane,
3(4)-isocyanatomethyl-8(9)-isocyanatopropyltricyclo[5,2,1,02,6]decane, 3(4)-isocyanatomethyl-8(9)-isocyanatobutyltricyclo[5,2,1,02,6]decane Cyclo[5,2,1,02,6]decane, 3(4)-isocyanatomethyl-8(9)-isocyanatopentyltricyclo[5,2,1,02,6]decane, 3(4) , 8(9)-di(isocyanatoethyl)tricyclo[5,2,1,02,6]decane, 3(4)-isocyanatoethyl-8(9)-isocyanatopropyltricyclo[5,2, 1,02,6]decane, 3(4)-isocyanatoethyl-8(9)-isocyanatobutyltricyclo[5,2,1,02,6]decane, 3(4)-isocyanatoethyl-8 (9)-isocyanatopentyltricyclo[5,2,1,02,6]decane and the like. Among these various polycyclic aliphatic diisocyanates, 2,5(6)-di(isocyanatomethyl)bicyclo[2,2,1]heptane (hereinafter abbreviated as BCHI) is particularly preferred. ) and 3(4), 8(9)
-di(isocyanatomethyl)tricyclo[5,2,1,
02,6]decane (hereinafter abbreviated as TCDI). These compounds are, for example, DE P3
,018,198.7 ,DE-OS 1,645,5
95 and No. 2,819,980, general formula (4)
In USP 3,143,570, a method for synthesizing compounds with h = 1, j = 1, and k = 1 is described in USP No. 3,143,570, using a sequential reaction of hydroformylation, reducing amino compound, and phosgenation from dimerized cyclopentadiene. In general formula (4), the compound in which h=0, j=1, and k=1 can be synthesized according to a method using a phosgenation reaction of the corresponding diamine. In the method of the present invention, the amounts of the linear aliphatic diisocyanate represented by the general formula (3) and the polycyclic aliphatic diisocyanate represented by the general formula (4) are determined in a molar ratio. The ratio is in the range of 1:11 to 11:1. A mixture in a molar ratio within this range is used as the raw material diisocyanate. The polyisocyanato-isocyanurate obtained by reacting within this range is a transparent viscous resinous liquid, and its viscosity changes depending on the mixing composition ratio of the raw materials. for example,
The starting materials BCHI and HDI exhibit fluidity at room temperature within this molar ratio range;
The polyisocyanato-isocyanurate obtained from the composition ratio I has high fluidity and heat resistance stability. In order to carry out the present invention, a diisocyanate mixture obtained by mixing raw material linear aliphatic diisocyanate and polycyclic aliphatic diisocyanate within the above range is mixed using a trimerization catalyst. , a so-called trimerization reaction is carried out. The trimerization catalyst used in the present invention includes, for example,
Tetraalkylammonium hydroxides and organic weak acid salts such as tetramethylammonium, tetraethylammonium, and tetrabutylammonium; hydroxyalkylammonium hydroxides such as trimethylhydroxypropylammonium, trimethylhydroxyethylammonium, triethylhydroxypropylammonium, and triethylhydroxyethylammonium; Oxides and organic weak acid salts, ■acetic acid, caproic acid, octylic acid,
Alkali metal salts of alkylcarboxylic acids such as myristic acid and metal salts of tin, zinc, lead, etc.; ■ Compounds containing aminosilyl groups such as hexamethyldisilazane; ■ Triethylamine, tributylamine, N,N-dimethylaniline, N
-ethylpiperidine, N,N'-dimethylpiperazine,
Mannich salts of phenolic compounds, N, N', N''-
tris(dimethylaminopropyl)-hexahydro-s
Examples include tertiary amines such as ym-triazine. Particularly preferred is a trimerization catalyst using a combination of an alkali metal salt of a carboxylic acid and a polyalkylene oxide compound or alcohol, and these catalysts exhibit excellent effects in terms of reactivity, reaction controllability, and the like. Examples of the alkali metal carboxylates include alkali metal formates, alkali metal acetates, alkali metal propionates, alkali metal octanoates, alkali metal benzoates, and potassium acetate is preferred. Examples of the polyalkylene oxide compound include polyethylene glycol or polypropylene glycol having a molecular weight of about 200 to 3,000, preferably polyethylene glycol having an average molecular weight of 400. Also, as alcohol, 2
-Alcohols such as ethylhexanol may also be used. The method of using these as trimerization catalysts is not particularly limited, and for example, the alkali metal carboxylic acid salt is usually used in a state dissolved in a polyalkylene oxide compound or alcohol. The amount of trimerization catalyst used is 0.000% based on the raw material diisocyanate mixture.
It ranges from 1 to 5% by weight, preferably from 0.001 to 2% by weight. In the reaction, examples of cocatalysts include ethylene glycol, 1, 3-butanediol, neopentyl glycol, 2-ethyl-1, 3-hexanediol,
trimethylolpropane, polypropylene glycol,
Alcohols such as phenol may also be used. These alcohols can be added at the same time as the isocyanurate catalyst, or can be reacted with the raw material diisocyanate to form a urethane bond before being transferred to the isocyanurate step. Especially ethylene glycol, 1,3-butanediol, neopentyl glycol, 2-ethyl-1,3-hexanediol, 2
, 2,4-trimethyl-1,3-pentanediol, trimethylolpropane, and other polyhydric alcohols can also be used as modifying agents for polyisocyanurate. These promoters may be used in approximately the same amount as the trimerization catalyst. The reaction may be carried out with or without a solvent. When a solvent is used, it is a matter of course to use a solvent that does not have reactive activity toward isocyanate groups. The reaction temperature is usually in the range of 20 to 120°C, preferably in the range of 50 to 90°C. Further, the reaction is preferably carried out under an atmosphere of an inert gas such as nitrogen, helium or argon. The progress of the reaction can be monitored by measuring the NCO% of the reaction solution and measuring the remaining amount of unreacted raw materials by gas chromatography. Generally, if the conversion reaction progresses too much, the viscosity of the product increases and the compatibility with the polyol decreases, so a method is used that lowers the conversion rate of the reaction, leaves unreacted raw materials, and removes them after stopping the reaction. be exposed. The reaction conversion rate is usually 3
The content should be 0 to 80% by weight. Once the reaction has reached the desired conversion rate, use an acid such as hydrogen chloride, sulfuric acid, phosphoric acid, p-toluenesulfonic acid, trifluorosulfonic acid, or a catalyst deactivator such as benzoyl chloride or acetyl chloride. is added to stop the reaction. The amount added is preferably in the range of 1.0 to 1.5 times the equivalent to neutralize the alkali metal salt of carboxylic acid. When the trimerization reaction is terminated, unreacted diisocyanate is mixed and the liquid is almost colorless and has a low viscosity. After stopping the reaction, the deactivated catalyst is removed from the reaction mixture if necessary, and then the unreacted raw materials and the used solvent are removed. The target polyisocyanato-isocyanurate can be obtained by removing unreacted raw materials or solvent, for example, by thin film distillation or solvent extraction. At this time, it is preferable to remove unreacted diisocyanate in the target product to a content of about 1% by weight or less. Whether the desired polyisocyanato-isocyanurate is obtained as substantially a single polyisocyanato-isocyanurate or as a mixture of polyisocyanato-isocyanurates is selected depending on the purpose of use; To obtain a single polyisocyanato-isocyanurate, there is a method of fractionating it by GPC. The viscosity of the polyisocyanate-isocyanurate mixture varies depending on the molar ratio of the starting isocyanates. For example, starting materials HDI and BC
If the molar ratio of HI is about 1:11 to 11:1, it exhibits fluidity at room temperature. [0028] There are no particular limitations on the equipment for carrying out the trimerization reaction, but a reactor equipped with a thermometer, nitrogen gas inlet, and cooling pipe so that the interior of the reaction solution can be sufficiently stirred is preferred. . The polyisocyanato-isocyanurate obtained as described above having a substantially single specific structure and a mixture of two or more structures can be used as a curing agent for a non-yellowing urethane paint resin, and Used as a raw material for resins and paint compositions. The obtained polyisocyanato-isocyanurate mixture is then mixed with an active hydrogen-containing compound after blocking the isocyanate groups with a blocking agent if necessary, to form a two-component non-yellowing type with excellent heat resistance and weather resistance. It can also be used as a resin for urethane paint. The blocking agent used is a compound having one or more active hydrogens in its molecule, such as phenol, cresol, xylenol, p-ethylphenol, O-isopropylphenol, p-tert-butylphenol, p-tert-
Octylphenol, thymol, p-naphthol, p-
Phenols such as nitrophenol and p-chlorophenol, alcohols such as methanol, ethanol, propanol, butanol, ethylene glycol, methyl cellosolve, butyl cellosolve, methyl carbitol, benzyl alcohol, phenyl cellosolve, furfuryl alcohol, and cyclohexanol, malon Active methylenes such as dimethyl acid, diethyl malonate, and ethyl acetoacetate; mercaptans such as butyl mercaptan, thiophenol, and tert-dodecyl mercaptan; acid amides such as ε-caprolactam, acetanilide, acetanisidine, acetamide, and benzamide; Imides such as acid imide and maleic acid imide, amines such as diphenylamine, phenylnaphthylamine, aniline, and carbazole, imidazoles such as imidazole and 2-ethylimidazole, ureas such as urea, thiourea, and ethylene urea, N-phenyl Carbamates such as phenyl carbamate and 2-oxazolidone, imines such as ethyleneimine, oximes such as formaldoxime, acetaldoxime, methyl ethyl ketoxime, and cyclohexanone oxime, sulfites such as sodium bisulfite and potassium bisulfite, etc. These compounds can be appropriately selected and used depending on the purpose and use. Further, these may be used alone or in combination. Blocking of isocyanate groups with these blocking agents can be achieved by mixing polyisocyanato-isocyanurate and a blocking agent in a roughly equivalent ratio when producing a curing agent for paint.
This is achieved by heating and stirring to about 130°C. The non-yellowing urethane paint resin of the present invention is
It is derived from the polyisocyanato-isocyanurate represented by the general formula (1) produced as described above or the polyisocyanato-isocyanurate with blocked NCO groups and a compound having at least two or more active hydrogens. It is a resin that Compounds containing at least two active hydrogens used to form this resin include compounds and polymers containing at least two active hydrogens in one molecule. Specifically, ethylene glycol, propylene glycol, β, β'-dihydroxy diethyl ether (diethylene glycol), dipropylene glycol, 1, 4-butylene glycol, 1, 3-butylene glycol, 1, 6-hexamethylene glycol, Neopentyl glycol, polyethylene glycol,
Glycols such as polypropylene glycol, polypropylene-polyethylene glycol, polybutylene glycol; glycerin, trimethylolpropane, hexanetriol, pentaerythritol, xylitol,
Alkane polyols such as sorbitol; polyols obtained by adding alkylene oxides (e.g., ethylene oxide, propylene oxide, 1,2-butylene oxide, etc.) alone or in mixtures to polyhydric alcohols such as glycerin or propylene glycol; Ether polyols, such as polyether polyols made by reacting alkylene oxide with polyfunctional compounds such as ethylenediamine and ethanolamine; dibasic acids (e.g. succinic acid, adipic acid, sebacic acid, dimer acid, carboxylic acids such as maleic anhydride, phthalic anhydride, isophthalic acid, and terephthalic acid) and polyhydric alcohols (e.g., ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, 1,4- Butylene glycol, 1, 3-butylene glycol, 1, 6-hexamethylene glycol,
Polyester polyol resins obtained by a condensation reaction with (selected from the group consisting of neopentyl glycol, glycerin, trimethylolpropane, etc.); a polymerizable monomer having one or more active hydrogen in one molecule; Acrylic polyol resins obtained by copolymerizing other monomers that can be copolymerized with, for example, (a) active hydrogen-containing acrylic esters (e.g., 2-hydroxyethyl acrylate, 2-hydroxyethyl acrylate, -Hydroxypropyl, acrylic acid-
2-hydroxybutyl, etc.), active hydrogen-containing methacrylic esters (e.g., 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, etc.), or acrylic acid monoesters of glycerin or (b) an acrylic ester (for example, methyl acrylate, ethyl acrylate, isopropyl acrylate) selected from the group consisting of methacrylic acid monoester, acrylic acid monoester of trimethylolpropane, or methacrylic acid monoester; , n-butyl acrylate, 2-ethylhexyl acrylate, etc., methacrylic esters (e.g., methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-methacrylate) (c) unsaturated carboxylic acids (e.g. acrylic acid, methacrylic acid, maleic acid,
itaconic acid, etc.), unsaturated amides (e.g., acrylamide, N-methylolacrylamide, diacetone acrylamide, etc.), and other polymerizable monomers (e.g.,
Glycidyl methacrylate, styrene, vinyltoluene,
(vinyl acetate, acrylonitrile, etc.); novolac type, β-methylepicro type, cyclic oxirane type, glycidyl ether type, glycidyl ester type, glycol ether type , epoxidized fatty acid unsaturated compounds, epoxidized fatty acid ester types,
Epoxy resins such as polyhydric carboxylic acid ester type, aminoglycidyl type, halogenated type, and resorcinol type, monosaccharides such as fructose, glucose, sucrose, lactose, 2-methyl glycoxide, and their derivatives, triglycerides, etc. Examples include aromatic or heterocyclic polyhydric alcohols such as methylolbenzene and tris(2-hydroxyethyl)isocyanurate. These may be used in combination,
Furthermore, these and other compounds containing two or more active hydrogens, such as compounds containing primary or secondary amino groups (e.g., ethylenediamine, triethylenediamine, hexamethylenediamine, m-xylylenediamine,
Diaminodiphenylmethane, isophoronediamine, diethylenetriamine, polyamines obtained by adding various alkylene polyamines and alkylene oxides, N,N'
-dimethylethylenediamine, etc.), substituted urea compounds (
For example, N,N'-dimethylurea, N-methyl-N'-
cyclohexylurea, etc.), thiol group-containing compounds (e.g., 1,2-ethanedithiol, 1,6-hexanedithiol, polyether polythiol, polyester polythiol, etc.), carboxyl group-containing compounds (e.g., succinic acid, adipic acid, sebacic acid) , terephthalic acid, carboxyl group-terminated polybutadiene, etc.) or compounds containing different active hydrogen-containing groups in one molecule (
For example, one or more compounds selected from monoethanolamine, thioethanolamine, lactic acid, β-alanine, etc.) can also be used in combination. Although various active hydrogen-containing compounds have been specifically illustrated above, the active hydrogen-containing compounds of the present invention are not limited to these,
Any active hydrogen-containing compound that can react with the isocyanato-isocyanurate used in the non-yellowing urethane paint resin of the present invention to form a urethane resin can be used, and various combinations can be selected. . Among the exemplified active hydrogen-containing compounds, methyl ethyl ketoxime is preferably used frequently. [0031] In forming the non-yellowing urethane paint resin of the present invention, the compound containing at least two active hydrogens and the isocyanato-isocyanurate are active hydrogen/NC
The equivalent ratio of O is 0.5 to 2, preferably 0.8 to 1
．． Use the mixture within the range of 2. When forming the non-yellowing type urethane paint resin of the present invention, a compound containing at least two active hydrogens and an isocyanato-isocyanurate are used together with a suitable solvent, for example, a hydrocarbon (such as benzene, toluene, xylene, cyclohexane, mineral spirits, naphtha, etc.), ketones (e.g., acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.), esters (e.g., ethyl acetate, n-butyl acetate, cellosolve acetate, isobutyl acetate, etc.), etc. The solvent can be appropriately selected and used depending on the purpose and use, and these solvents may be used alone or in combination. Furthermore, various additives used in the technical field such as catalysts, pigments, leveling agents, antioxidants, flame retardants, plasticizers, and surfactants can be mixed and used depending on the purpose and use. [0032] In the embodiment of forming the non-yellowing type urethane paint resin according to the present invention, immediately before forming the polyurethane resin, polyisocyanato-isocyanurate and an active hydrogen-containing compound, as well as solvents and additives are added depending on the purpose and use. In addition, a composition is prepared and a resin is formed usually at a temperature in the range from room temperature to 150°C to obtain a composition containing this resin, or a so-called block is obtained by blocking the NCO groups of polyisocyanato-isocyanurate with a blocking agent. Isocyanato-isocyanurate, active hydrogen-containing compounds, and various additives used in the technical field such as solvents, catalysts, pigments, leveling agents, antioxidants, plasticizers, and surfactants depending on the purpose and use. A composition containing these resins can be obtained by blending the following ingredients and forming a resin at a temperature range of 100°C to 250°C. When the non-yellowing urethane paint resin of the present invention is used as a paint, it has excellent adhesion to coated objects such as metals, plastics, rubber, leather, and concrete.
It can be used for a wide range of purposes as a coating for equipment, building materials, woodwork, etc. Furthermore, the curing agent for powder coatings included in the present invention contains 2,5- and/or 2,6-diisocyanatomethylbicyclo[2,2,1]heptane or a modified product thereof in the molecule. This is a blocked isocyanate synthesized from a blocking agent having at least one active hydrogen, and the powder coating obtained using this is excellent in low-temperature curability and weather resistance. 2,5- and/or 2,6-diisocyanatomethylbicyclo[2,2,1]heptane (
(hereinafter abbreviated as BCHI) means 2,5-diisocyanatomethylbicyclo[2,2,1]heptane, 2,6
-diisocyanatomethylbicyclo[2,2,1]heptane, either alone or as a mixture, or modified products thereof. Suitable modified products include urethane prepolymers having active isocyanate groups at the terminals obtained by reacting excess BCHI with water, diols or polyols, or polyisocyanates having isocyanurate bonds obtained by trimerizing BCHI. be. Particular preference is given to polyisocyanates obtained by trimerization of BCHI. Furthermore, a mixture containing residual monomers in these modified products may be used. Examples of the diols or polyols used in the synthesis of the urethane prepolymer having an active isocyanate group at the terminal include ethylene glycol, diethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, 1, 3-butanediol,
Diols such as 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, 3-methylpentanediol, or trimethylolpropane,
Examples include polyols such as glycerin, polyester polyol, and epoxy polyol. Furthermore, in addition to the above-mentioned BCHI or its modified product, it is also possible to use it in combination with other known isocyanates. In this case, from the viewpoint of low temperature curability, it is necessary to synthesize the urethane prepolymer so that its terminal end is BCHI. Other known isocyanates that can be used in combination include aliphatic or alicyclic diisocyanates such as isophorone diisocyanate (IPDI) and hexamethylene diisocyanate (HDI), or tolylene diisocyanate (TD).
I), aromatic diisocyanates such as diphenylmethane diisocyanate (MDI), or modified products such as urethane modified products, carbodiimide modified products, isocyanurate modified products, and adducts of these aliphatic or alicyclic diisocyanates or aromatic diisocyanates; Coarse T
Examples include polyisocyanates such as DI and polymethylene polyphenylene polyisocyanate (polymeric MDI). [0036] In addition, at least one active hydrogen is contained in one molecule.
Specific blocking agents include ε-caprolactam, methyl ethyl ketoxime, methyl isobutyl ketoxime, cyclohexanone oxime, ethyl acetoacetate, phenol, etc.; ,
Methyl isobutyl ketoxime, cyclohexanone oxime and the like are preferred. The curing agent for powder coatings of the present invention is
It is synthesized by a conventional method using the above-mentioned BCHI, its modified product, or a mixture thereof and a blocking agent having at least one active hydrogen per molecule. The obtained curing agent for powder coating can be used as a powder coating by blending polyester polyol and other additives. Further, the composition for a polyester powder coating of the present invention is a composition containing the above-mentioned curing agent for a powder coating and a polyester polyol, and the blending ratio of the curing agent for a powder coating and the polyester polyol is , the blocking agent of isocyanato-isocyanurate with blocked NCO groups comes off at the baking temperature and dissociates isocyanate groups (NC
The active hydrogen (H
) equivalent ratio (H/NCO group) is 0.8 to 1.3
, preferably in the range of 0.9 to 1.2. The above polyester polyol combines the above diols or polyols with a polybasic acid, such as phthalic anhydride,
Isophthalic acid, terephthalic acid, dimethyl terephthalic acid,
It is obtained by a condensation reaction with polybasic acids commonly used in polyester synthesis, such as adipic acid, azelaic acid, sebacic acid, and trimellitic anhydride. The polyester polyol used in the present invention must have a hydroxyl group at the end of the molecule, and must be synthesized under conditions in which the concentration of hydroxyl groups in the molecule is in excess of the concentration of carboxyl groups. In addition to the polyester polyol, the polyester powder coating composition of the present invention contains, for example, inorganic pigments such as titanium oxide, barium sulfate, calcium carbonate, iron oxide, and talc, phthalocyanine blue, phthalocyanine green, and carbon black. There is no problem in adding organic pigments such as, as well as auxiliary materials such as surface preparation agents, ultraviolet absorbers, antioxidants, and curing catalysts. Conventionally, this type of powder coating required a baking temperature of 180°C or higher even when combined with a curing catalyst, but by using the powder coating curing agent of the present invention, it is now possible to bake at a low temperature of 160°C. Become,
Moreover, a coating film with excellent weather resistance can be obtained. [Function and Effect] The polyisocyanato-isocyanurate of the present invention has (1) a solid content of 100%, that is, exhibits fluidity even at room temperature in a solvent-free state, and has good workability. ■High N
It has a CO content and can reduce the amount of isocyanate used relative to the polyol. (2) It has good thermal stability derived from isocyanate groups, and harmful isocyanate monomers are rarely produced by decomposition. ■
It has characteristics such as having a stable polycyclic structure. Moreover, the production method is a method that allows the desired polyisocyanato-isocyanurate or a mixture thereof to be obtained efficiently with good selectivity and in a simple manner. [0040] Polyurethane paints using this polyisocyanato-isocyanurate as a curing agent generally have good adhesion to various coated objects, a balance between hardness and flexibility, crack resistance, water resistance, chemical resistance, gloss, In addition to its excellent appearance, it also has excellent weather resistance, light stability, and thermal stability. That is, the polyisocyanato-isocyanurate of the present invention has higher reactivity and heat resistance than, for example, aliphatic isocyanato-polyisocyanurate derived from hexamethylene diisocyanate. Non-yellowing urethane paint resins have fast initial curing and drying properties and significantly reduce yellowing during baking. In addition, it has good compatibility, excellent appearance, and coating performance equivalent to or better than commercially available products, making it suitable for applications where workability, appearance, and coating performance are important, such as vehicle painting. When a blocked isocyanate synthesized from 2,5- and/or 2,6-diisocyanatomethylbicyclo[2,2,1]heptane is used as a curing agent for powder coatings, it is possible to What used to require a baking temperature of 180°C or higher can now be baked at a low temperature of 160°C, and has excellent weather resistance. [Example] The present invention will be explained in more detail below using reference examples, working examples, and comparative examples. However, the present invention is not limited to these specific examples. Note that all percentages in these examples are percentages by weight. Reference Example 1 2,5(6)-diisocyanatomethyl-bicyclo[2.
2.1] Production of heptane (hereinafter abbreviated as BCHI) 687 g of isoamyl acetate and 2189 g of orthodichlorobenzene (hereinafter abbreviated as ODCB) were mixed as a solvent for salt formation and phosgenation (hereinafter abbreviated as mixed solvent). It was prepared as (called). The ratio of ODCB in this mixed solvent is 76.1%. 1126 g of the mixed solvent was placed in a 3 liter four-necked flask, and the mixture was cooled to 5° C. with ice water while stirring. Add hydrogen chloride gas to this at 1.6Nl/min.
After blowing for 30 minutes at a ratio of
About 60% of the 2,5-isomer (abbreviated as CHA) and 2
, 6-isomer mixture of about 40% 250.0g (1.6
A solution of (2 mol) dissolved in 1750 g of mixed solvent (
Raw material diamine concentration: 12.5%) was dropped into the liquid in the flask over 2 hours. Cooling was continued during the dropwise addition to maintain the flask internal temperature at 10 to 15°C. Further, the blowing of hydrogen chloride gas was continued at a rate of 1 Nl/min. Even after dropping the raw material diamine solution, the internal temperature of the flask was kept at 25%.
While keeping the temperature below ℃, blow in hydrogen chloride gas to 0.
The salt formation reaction was continued for 2 hours at a rate of 4 Nl/min to complete the salt formation reaction. The salt-forming reaction proceeded extremely smoothly without the formation of agglomerates of hydrochloride particles, and a white uniform slurry of fine particles was obtained. After the salt-forming reaction was completed, the internal temperature of the flask was raised from 25°C to 160°C over 50 minutes, and phosgene was gradually blown into the flask from 100°C to start the phosgenation reaction. Internal temperature with mantle heater
Blow in phosgene while adjusting the temperature to 160±1℃.
This was continued at a rate of 100-120 g/h. Approximately 6 hours after the start of phosgene blowing, the nature of the reaction liquid changed from a white slurry to a clear orange-red color, so after blowing phosgene gas at a rate of 50 g/h for another 30 minutes, the phosgenation reaction was terminated. Total phosgenation reaction time 6.
It was 5 hours. The amount of phosgene gas used was approximately the theoretical amount.
It was 2.2 times. After that, add N2 to the reaction solution in the flask.
Gas was blown at a rate of 1.3 Nl/min for 80 minutes to perform degassing. During this time, the liquid temperature was 160±1℃.
And so. The reaction solution was degassed, cooled, and filtered through filter paper (5C) to remove trace amounts of solid content. After removing the solvent from the filtrate, it was rectified under vacuum at 110-116°C/0.4-
306.5 g of main fraction at 0.6 torr was obtained. The analytical values of this product were as follows. NCO%
40.72 Hydrolyzable chlorine
0.032%
Gas chromatograph purity% 99
．． 8 Hydrolyzable chlorine after desolvation
0.202g/100g-BCHI The obtained main fraction was confirmed to be BCHI from the results of elemental analysis, IR spectrum, NMR spectrum, etc. In addition, the yield of the main fraction is the theoretical value (1.62 mol, 33
4.2g) was 91.7%. Example 1 1,6-hexamethylene diisocyanate (hereinafter referred to as HD
Production of polyisocyanato-isocyanurate by cyclic trimerization of a mixture of (sometimes abbreviated as I) and BCHI ■Preparation of catalyst mixture (hereinafter abbreviated as catalyst A) 1.0 g of dried anhydrous potassium acetate was prepared on average. It was prepared by dissolving it in 9 g of polyethylene glycol having a molecular weight of 400. ■
Production of polyisocyanato-isocyanurate by cyclic trimerization 100 g (0.595 mol) of 1,6-hexamethylene diisocyanate and 100 g of BCHI are placed in a four-necked flask equipped with a thermometer, cooling tube, nitrogen introduction tube, and stirring blade.
(0.485 mol) and 1.6 g of catalyst A were added, and the mixture was heated at 80°C.
The temperature rose to After 2.5 hours, the NCO content was 45.
When the percentage decreased from 35% to 24.3%, 0.25 g of benzoyl chloride was added and stirred at 60°C for 1 hour to remove trimerization catalyst A.
was inactivated. A clear viscous liquid with a slightly yellow color was obtained. The reaction mass obtained in this way was heated to 0.2 torr.
Thin film distillation was carried out under a vacuum of 110 ml to remove unreacted raw materials.
g of a polyisocyanato-isocyanurate mixture was obtained. This was dissolved in 110 g of butyl acetate to obtain a solution of polyisocyanato-isocyanurate having the following resin constant. Resin Constant Furthermore, the molecular ratio of the methyl carbamate compound obtained by reacting a part of this solution with methyl alcohol was determined by gel permeation chromatography (hereinafter referred to as GPC analysis) as follows. From this GPC analysis, there was almost no formation of high polymers with n=6 or more, and it was possible to produce polyisocyanato-isocyanurate containing 30% by weight or more of n=1 polymers. Furthermore, the above-mentioned methyl carbamate compound was subjected to GPC again to separate each component. Among them, n = 1 body (
NMR spectrum, FD for the fraction of trimer)
-MS spectra were measured and analyzed. In the analysis, reference was made to the spectrum of the n=1 body (trimer) obtained by fractionating the methyl carbamate compound of the BCHI monomer single trimer by GPC. From the FD-MS spectrum,
Mass numbers of 600, 638, 676, and 714 were detected. This is a trimerization of BCHI and HDI alone, and a 2:1 molar ratio of BCHI and HDI, respectively.
: corresponds to the molecular weight of the trimerized compound at a 2 molar ratio. From the above analysis results, it was found that the compound represented by formula (1) was obtained. In addition, in the 13C-NMR spectrum, there was a methylene carbon signal of HDI (26.7 ppm,
30 ppm, 41 ppm) and the carbon signal of the bicyclo ring of BCHI (28 ppm to 47 ppm) and the carbon signal of the carbonyl group of the trimer ring (150 ppm).
pm) are observed separately, so 13C
-The composition ratio of BCHI and HDI can be determined from the NNE mode of NMR. Example 2 Production of polyisocyanato-isocyanurate by cyclic trimerization of a mixture of 1,6-hexamethylene diisocyanate and BCHI Four-necked flask with thermometer, cooling tube, nitrogen introduction tube, and stirring blade 140g (0.832mol) of HDI and BCHI
60 g (0.291 mol) of the mixture and catalyst A were added to 1.
5g was added and the temperature was raised to 80°C. 4.0 hours later, NC
Since the O content decreased from 47.2% to 36.4%, 0.114 g of benzoyl chloride was added and stirred at 60° C. for 1 hour to deactivate trimerization catalyst A. A clear viscous liquid with a slightly yellow color was obtained. The reaction mass obtained in this way is
Thin film distillation was performed under a vacuum of 0.2 torr to remove unreacted raw materials, yielding 65 g of a polyisocyanato-isocyanurate mixture. This was dissolved in 65 g of butyl acetate to obtain a solution of polyisocyanato-isocyanurate having the following resin constant. Example 3 Production of polyisocyanato-isocyanurate by cyclic trimerization of a mixture of 1,6-hexamethylene diisocyanate and BCHI A four-necked flask equipped with a thermometer, a cooling tube, a nitrogen introduction tube, and a stirring blade was used. HDI 180g (1.070mol) and BCHI
20 g (0.097 mol) of the mixture and catalyst A were added to 1.
6g was added and the temperature was raised to 80°C. 4.0 hours later, NC
Since the O content decreased from 49.1% to 34.7%, 0.114 g of benzoyl chloride was added and stirred at 60° C. for 1 hour to deactivate trimerization catalyst A. A clear viscous liquid with a slightly yellow color was obtained. The reaction mass obtained in this way is
Thin film distillation was performed under a vacuum of 0.2 torr to remove unreacted raw materials, yielding 72 g of a polyisocyanato-isocyanurate mixture. This was dissolved in 72 g of butyl acetate to obtain a solution of polyisocyanato-isocyanurate having the following resin constant. Example 4 BCHI 180g (1.144mol), HDI20
g (0.119 mol) The reaction was carried out in the same manner as in Example 2, except that 1 g (0.119 mol) was used. NCO content ranges from 41.7% to 31.
It decreased to 5%. Benzoyl chloride is a catalyst poison.0.
114g was used. After thin film distillation, residual BCHI 0.01%
, residual HDI trace amount, NCO content 17.5%, viscosity 3
86 g of a polyisocyanato-isocyanurate mixture at 6,000 cps/25 DEG C. was obtained. Example 5 In the same manner as in Example 1, 100 g (0.406
mol) and 100 g (0.594 mol) of HDI was added with 1.5 g of catalyst A, and after raising the temperature to 80° C., the reaction was carried out for 4 hours. NCO content decreased from 42.1% to 33.7%. Benzoyl chloride 0.21
g was added thereto, and the reaction was carried out at 60°C for 1 hour. 0 from product
．． Unreacted diisocyanate monomer was removed using a thin film distillation apparatus under a vacuum of 2 torr. Residual TCDI0.40
%, residual HDI 0.01% or less, NCO content 16.
5% polyisocyanato-isocyanurate mixture 73
g was obtained. Example 6 TCDI 60g (0.244 mol), HDI 140
The reaction was carried out in the same manner as in Example 5, except that g (0.832 mol) was used. NCO content ranges from 45.2% to 34
．． It decreased to 9%. Benzoyl chloride is a catalyst poison 0
．． 114g was used. After thin film distillation, residual TCDI is 0.40
%, residual HDI 0.01% or less, NCO content 17
．． 3% polyisocyanato-isocyanurate mixture 6
6g was obtained. Example 7 In the same manner as in Example 1, 20 g (0.097 mol) of BCHI, 20 g (0.080 mol) of TCDI, and
and 160 g (0.832 mol) of catalyst A.
1.5g of was added, the temperature was raised to 80°C, and the reaction was carried out for 4 hours. NCO content decreased from 47.2% to 36.1%. Add 0.114g of benzoyl chloride and 60℃
The reaction was carried out for 1 hour. Unreacted diisocyanate monomer was removed from the product using a thin film distillation apparatus under a vacuum of 0.2 torr. Residual BCHI 0.10%, remaining TCD
I0.30%, residual HDI 0.01% or less, NCO
68 g of a polyisocyanato-isocyanurate mixture with a content of 19.0% were obtained. Example 8 BCHI 50g (0.242 mol), TCDI 50
g (0.203 mol) and HDI100 g (0.59
The reaction was carried out in the same manner as in Example 7 except that 4 mol) was used. NCO content decreased from 43.7% to 34.1%. 0.114 g of benzoyl chloride was used as a catalyst poison. After thin film distillation, residual BCHI 0.10%, residual TCD
I0.40%, residual HDI 0.01% or less, NCO
69 g of a polyisocyanato-isocyanurate mixture with a content of 16.9% were obtained. Example 9 Production of polyisocyanato-isocyanurate by cyclic trimerization of BCHI 200 g of BCHI (0.97 g
mol) and 1.5 g of catalyst A were added, and the temperature was raised to 80°C. After 2.0 hours, the NCO content decreased from 40.7% to 30
．． When the amount decreased to 5%, 0.114 g of benzoyl chloride was added and stirred at 60° C. for 1 hour to deactivate trimerization catalyst A. A clear viscous liquid with a slightly yellow color was obtained. The reaction mass thus obtained was subjected to thin film distillation under a vacuum of 0.2 Torr to remove unreacted raw materials, yielding 80 g of a polyisocyanato-isocyanurate mixture. This was dissolved in 80 g of butyl acetate to obtain a polyisocyanato-isocyanurate solution having the following resin constant. Comparative Example 1 Production of polyisocyanato-isocyanurate by cyclic trimerization of a mixture of HDI and IPDI 1,6-hexamethylene diisocyanate was placed in a four-necked flask equipped with a thermometer, a cooling tube, a nitrogen introduction tube, and a stirring blade. A mixture of 100 g (0.59 mol) of isophorone diisocyanate and 100 g (0.45 mol) of isophorone diisocyanate and 1.5 g of catalyst A were added, and the temperature was raised to 80°C. After 4.0 hours, the NCO content decreased to 34.7%, so 0.215 g of benzoyl chloride was added and
The mixture was stirred at 0° C. for 1 hour to deactivate the trimerization catalyst A. A clear viscous liquid with a slightly yellow color was obtained. The reaction mass thus obtained was subjected to thin film distillation under a vacuum of 0.2 Torr to remove unreacted raw materials, yielding 82 g of a polyisocyanato-isocyanurate mixture. This was dissolved in 82 g of butyl acetate to obtain a polyisocyanato-isocyanurate solution having the following resin constant. Example 10 (Blocking reaction) 19.6 g (0.231 mol) of methyl ethyl ketoxime was added to 100 g of polyisocyanato-isocyanurate obtained in the same manner as in Example 1.
After stirring at 0°C for 3 hours, the isocyanate content decreased to 0.
It was 0.2%. This was cooled to obtain a block urethane with an effective isocyanate content of 7.73%. Examples 11 to 14, Comparative Examples 2 to 5 Polyisocyanato-isocyanurate solutions obtained in Examples 1 to 3 and acrylic polyol resin solution OLESTAR Q18
2 (manufactured by Mitsui Toatsu Chemical Co., Ltd., number average molecular weight 9500, solid content 50% by weight, hydroxyl value 45 mgKOH/g) to conduct a coating film test. (2) Preparation of base enamel Base enamel of acrylic resin Orester Q182 was prepared by blending as follows. Acrylic resin Orester Q182
50 parts Pigment: Titanium oxide R
930 (manufactured by Ishihara Sangyo Co., Ltd.) 50 parts were blended in the above proportions, and the pigment was kneaded in using a triple roll to prepare a base enamel. ■Polyisocyanato-isocyanurate solutions obtained in coating film test Examples 1 to 3 and acrylic polyol resin OLESTAR Q18
The base enamel prepared in 2 and
To this, ethyl acetate/toluene/butyl acetate/xylene/cellosolve acetate (
A mixed solvent (weight ratio = 30/30/20/15/5) was added, and the temperature was adjusted to 15 seconds/25° C. using a Ford cup #4 to obtain a non-yellowing urethane paint resin of the present invention. Use this with an air spray gun (IWATAW-77 type, nozzle diameter 2m).
mφ) to a steel plate and glass plate to a dry film thickness of 25μ (microns), and at room temperature (20℃/60%RH)
After being allowed to stand for 7 days, it was used for testing. In addition, for comparison, the polyisocyanates obtained in Example 9 and Comparative Example 1 were
Three types of aliphatic polyisocyanates as isocyanurate solutions and conventional products, namely (1) Olester NP1
000 (manufactured by Mitsui Toatsu Chemical Co., Ltd., buret of hexamethylene diisocyanate), (2) Coronate EH
(manufactured by Nippon Polyurethane Co., Ltd., isocyanurate of hexamethylene diisocyanate), (3) IPDI
Similar tests were conducted on T1890 (manufactured by Daicel Huels, isocyanurate of isophorone diisocyanate). The performance and physical properties of the coating film are shown in Tables 1 and 2. The coating film test was conducted at 20° C./60% RH, and the evaluation method was based on JIS k-5400. The test methods for items (1) to (9) shown in the table are as follows. (1) Adhesion, based on JIS D-0202. (2) Eriksen extrusion, JIS Z-2247
Compliant with. (3) Magic stain resistance, compliant with JAS 1373. Place the test piece horizontally and apply JIS-6037 on the surface of the test piece.
(1964), a line with a width of 10 mm was drawn with quick-drying ink, left for 24 hours, and then wiped off with a cloth soaked in ethyl alcohol. Depending on the result, the following display will be made. ○: No abnormality, △: Slight trace remains, ×: Mark clearly remains. (4) Xylene rubbing (50 times): Place the test piece in a dyeing rub fastness tester, apply a load of 500 g with a cotton cloth impregnated with 2 ml of xylene, and repeat the test 50 times. Depending on the result, the following display will be made. ○: No abnormality, △: Slight trace remains, ×: Mark clearly remains. (5) Acid resistance and alkali resistance, compliant with JAS 1373. Place the test piece horizontally, drop 10% sulfuric acid water (10% caustic soda water) onto the surface of the test piece, cover it with a watch glass for 24 hours, and then leave it at room temperature for 24 hours. As a result,
Displays the following. ○: No abnormality, △: Slight trace remains, ×: Mark clearly remains. (6) WOM yellowing index, based on JIS k-7103. (7) Gloss (60° gloss), JIS k-540
Compliant with 0. (8) DuPont impact (1/2in/500g), JI
Compliant with S k-5400. (9) Secondary physical properties: Measure physical properties after immersing in boiling water for 4 hours. Examples 15-18, Comparative Examples 6-9 Olestar Q173 (commercially available polyester polyol resin)
Manufactured by Mitsui Toatsu Chemical Co., Ltd., solid content 100%, hydroxyl value
256mgKOH/g) was prepared and sprayed in the same manner as in Example 11, force-dried at 150°C for 20 minutes, left to stand at room temperature (20°C/60% RH) for 7 days, and then tested. provided. The results are summarized in Tables 3-5. The coating film test and evaluation method is the same as described above. Reference Example 2 Production of acrylic polyol resin 150 g of 2-hydroxyethyl methacrylate, 50 g of methyl methacrylate, 150 g of n-butyl methacrylate
g, n-butyl acrylate 25g, styrene 125g
, a monomer mixture containing 15 g of acrylic acid, 25 g of diethylene glycol, and 50 g of tert-butyl peroxy-2-ethylhexanoate was continuously added dropwise to the reflux solution of 1200 g of n-butyl acetate over 2 hours while stirring. The mixture was further refluxed for 5 hours for polymerization. After the polymerization reaction is complete, part of the n-butyl acetate is distilled off to reduce the solid content to 80%.
It was prepared as follows. The acrylic polyol resin solution thus obtained had a viscosity of 6500 cp/25°C and a number average molecular weight of 130.
0, and the hydroxyl value was 92 mgKOH/g. Reference Example 3 Preparation of Base Enamel The acrylic resin base enamel produced in Reference Example 2 was prepared by blending as follows. Acrylic polyol resin produced in Reference Example 2
45 parts Pigment: Titanium oxide R930 (
Ishihara Sangyo Co., Ltd.) 45 parts Thinner (xylene/toluene/butyl acetate)
/methyl isobutyl ketone) 10
A base enamel was prepared by blending the above proportions and kneading the pigments using a triple roll. Example 19, Comparative Example 10 The block urethane solution of polyisocyanato-isocyanurate obtained in Example 10, the acrylic polyol resin solution shown in Reference Example 2, and the base enamel prepared in Reference Example 3 were effectively used. The isocyanate groups and hydroxyl groups are blended in equivalent amounts and the pigment content (PWC) is 40% by weight, and to this, ethyl acetate/toluene/butyl acetate/xylene/cellosolve acetate (weight ratio = 30/30/2) is added as a thinner.
Add a mixed solvent of 0/15/5) and use a Ford cup #4.
The temperature was adjusted to 15 seconds/25° C. to obtain a non-yellowing urethane paint resin of the present invention. Use this with an air spray gun (IWA)
TAW-77 model, nozzle diameter 2mmφ) was used to coat steel and glass plates to a dry film thickness of 25μ (microns), force-dried at 150℃ for 20 minutes, and then heated to room temperature (20℃/
60% RH) for 7 days, and then subjected to testing. The evaluation method is the same as described above. Further, for comparison with conventional products, similar tests were conducted on OLESTAR NP1060PB (manufactured by Mitsui Toatsu Chemical Co., Ltd., block urethane in the form of a hexamethylene diisocyanate burette). The performance of the composition and the physical properties of the coating film are shown in Table 2. As a result of the above,
Polyurethane paints generally have excellent adhesion to various objects, balance between hardness and flexibility, crack resistance, water resistance, chemical resistance, gloss, appearance, etc., but the composition of the present invention is used as a paint. The polyurethane coating film obtained by this process also has these properties, as well as excellent weather resistance, light stability, and thermal stability, and also has various superior characteristics compared to commercially available polyurethane coatings. are doing. That is, the polyisocyanato-isocyanurate used in the non-yellowing urethane paint resin of the present invention has higher reactivity and heat resistance than polyisocyanates derived from aliphatic isocyanates, such as hexamethylene diisocyanate. Therefore, the initial curing and drying properties are fast, and yellowing during baking is greatly improved. In addition, it has good compatibility, excellent appearance, and coating performance equivalent to or better than commercially available products, making it suitable for applications where workability, appearance, and coating performance are important, such as vehicle painting. Example 20 Synthesis of Blocked Isocyanate-1 134 parts of trimethylolpropane and 300 parts of ethyl acetate were charged into a reaction vessel while blowing nitrogen gas.
The temperature was raised to 80°C while stirring. Furthermore, the above BCH
It took 1 hour to prepare 556 copies of I. 8 after finishing preparation
After reacting at 0℃ for 10 hours, ε-caprolactane
276 parts were charged and the reaction was further carried out at 80°C for 4 hours. The obtained solution was distilled using a Smith distiller to obtain solid blocked isocyanate-1. Example 21 Synthesis of Blocked Isocyanate-2 Xylene 16 was added while blowing nitrogen gas into the reaction vessel.
Add 7 parts and 500 parts of BCHI and mix while stirring.
After raising the temperature to 15℃, steam was blown in to reduce the NCO% to 18.
%, the temperature was cooled to 50°C, 254 parts of methyl ethyl ketoxime was added dropwise over 1 hour, and the temperature was further cooled to 50°C.
Allowed time to react. The obtained solution was distilled using a Smith distiller to obtain solid blocked isocyanate-2. Example 22 Synthesis of Blocked Isocyanate-3 While blowing nitrogen gas into the reaction vessel, 50% butyl acetate was added.
0 parts of BCHI and 500 parts of BCHI were charged, and reacted with 3.8 parts of catalyst A at 80° C. for 4 hours while stirring to obtain an isocyanurate type polyisocyanate having an NCO% of 6%. 165 parts of ε-caprolactam was added to the obtained solution, heated to 110° C., reacted for 4 hours, and then distilled using a Smith distiller to synthesize solid blocked isocyanate-3. Example 23 and Comparative Example 11 As the main agent, ELITEL ER6610 (manufactured by Nippon Ester Co., Ltd.,
Polyester resin (OH value: 31 KOHmg/g) was used and combined with block isocyanates 1 to 3 synthesized in Examples 20 to 22 to prepare Examples. In addition, B1530 (manufactured by Huls, blocked IPDI) was used as a comparative example. The formulations shown in Examples and Comparative Examples in Table 6 were blended and mixed in a Henschel mixer, followed by melt-kneading in a twin-screw kneader. Furthermore, the obtained paint was finely pulverized and sieved to prepare a powder paint. After that, electrostatic coating was performed on the zinc phosphate treated iron plate using an electrostatic coating machine at 160℃ and 180℃.
Baking was carried out for 20 minutes at a baking temperature of °C. The thickness of the resulting coating film was 70±5 μm. From the results in Table 6, it is clear that even with the conventional curing catalyst combination system, a baking temperature of 180°C or higher was required; It is clear that by using the synthesized blocked isocyanate as a curing agent for powder coatings, low-temperature baking at 160°C is possible. [Table 1] [Table 2] [Table 3] [Table 4] [Table 5] [Table 6]

Claims (28)

[Claims] [Claim 1] General formula (1) [Formula, R1, R2 and R3 have 2 to 1 carbon atoms]
2 alkylene group or formula (2) [Formula 2] (wherein k is 0 to 2, j and m are 1 to 5, and h is 0 to
(represents an integer of 2), which may be the same or different from each other, and n represents an integer of 1 to 5.
A polyisocyanato-isocyanurate mixture containing more than one species. 2. The polyisocyanato-isocyanurate mixture according to claim 1, wherein in general formula (1), n=1. 3. The polyisocyanato-isocyanurate mixture according to claim 1, wherein in general formula (1), n=2 to 5. 4. Contains 30 to 90% by weight of polyisocyanato-isocyanurate where n is 1 and 10 to 70% by weight of polyisocyanato-isocyanurate where n is 2 to 5 in general formula (1). A polyisocyanato-isocyanurate mixture according to claim 1. [Claim 5] General formula (3) OCN-R4-NCO
(3) (wherein, R
4 represents an alkylene group having 2 to 12 carbon atoms) and a linear aliphatic diisocyanate represented by the general formula (4) [
Chemical formula 3] (where k is 0 to 2, j and m are 1 to 5, and h is 0 to
2. The polyisocyanato-isocyanurate mixture according to claim 1, which is obtained by reacting a polycyclic aliphatic diisocyanate represented by the integer of 2. 6. The polyisocyanato-isocyanurate mixture according to claim 5, wherein the linear aliphatic diisocyanate represented by general formula (3) is hexamethylene diisocyanate. 7. The polycyclic aliphatic diisocyanate represented by the general formula (4) is 2,5- or 2,6-diisocyanatomethylbicyclo[2,2,1]heptane or a mixture thereof. The polyisocyanato-isocyanurate mixture according to claim 5. 8. The linear aliphatic diisocyanate represented by the general formula (3) is hexamethylene diisocyanate, and the polycyclic aliphatic diisocyanate represented by the general formula (4) is The polyisocyanato-isocyanurate mixture according to claim 5, which is 2,5- or 2,6-diisocyanatomethylbicyclo[2,2,1]heptane or a mixture thereof. 9. In the general formula (1) according to claim 1, n is 1, and at least one of R1, R2 and R3 is represented by the formula (2) [Image Omitted] (wherein k is 0 to 2, j and m are 1-5, h is 0-2
), with the remainder having 2 to 2 carbon atoms.
A substantially single polyisocyanato-isocyanurate having 12 alkylene groups. [Claim 10] General formula (3) OCN-R4-NCO
(3) (wherein, R4 has 2 carbon atoms
to 12 alkylene groups) and a linear aliphatic diisocyanate represented by the general formula (4) [Chemical formula 5] (where k is 0 to 2, j and m are 1 to 5, and h is 0 ~2
A mixture with a polycyclic aliphatic diisocyanate represented by (representing an integer of and approximately 20 to 50 of the initially present isocyanate groups.
% is trimerized, a catalyst poison is immediately added to inactivate the catalyst, and after the trimerization reaction is stopped, unreacted diisocyanate is removed. In the formula, R1, R2 and R3 have 2 to 1 carbon atoms.
2 or an alkylene group of formula (2)
(represents an integer of 1 to 5), which may be the same or different from each other, n represents an integer of 1 to 5]
A method for producing a polyisocyanato-isocyanurate mixture containing two or more types of polyisocyanato-isocyanurates represented by: 11. The production method according to claim 10, wherein the trimerization catalyst is used in combination with an alkali metal salt of a carboxylic acid and a polyalkylene oxide compound or alcohol. 12. The production method according to claim 10, wherein the linear aliphatic diisocyanate represented by general formula (3) is hexamethylene diisocyanate. 13. The polycyclic aliphatic diisocyanate represented by the general formula (4) is 2,5- or 2,6-diisocyanatomethylbicyclo[2,2,1]heptane or a mixture thereof. The manufacturing method according to claim 10. 14. The linear aliphatic diisocyanate represented by the general formula (3) is hexamethylene diisocyanate, and the polycyclic aliphatic diisocyanate represented by the general formula (4) is 11. The method according to claim 10, wherein the methylbicyclo[2,2,1]heptane is 2,5- or 2,6-diisocyanatomethylbicyclo[2,2,1]heptane or a mixture thereof. 15. Non-yellowing type urethane paint containing a polyisocyanato-isocyanurate mixture represented by the general formula (1) according to claim 1 as a curing agent and a compound having two or more active hydrogens as a main ingredient. resin. 16. The polyisocyanate according to claim 5.
A non-yellowing urethane paint resin that uses an isocyanurate mixture as a curing agent and a compound having two or more active hydrogens as a main ingredient. 17. The polyisocyanate according to claim 9.
A non-yellowing urethane paint resin that uses isocyanurate as a curing agent and a compound that has two or more active hydrogens as its main ingredient. 18. Claim 15, wherein the blending ratio of the polyisocyanato-isocyanurate mixture and the compound having two or more active hydrogens is 0.8 to 1.2 in terms of equivalent ratio (H/NCO group). 17. The non-yellowing urethane paint resin according to 16 or 17. 19. A coating composition containing the non-yellowing urethane coating resin according to claim 15, 16 or 17. 20. The isocyanate group of the polyisocyanato-isocyanurate mixture represented by the general formula (1) according to claim 1 is blocked by a compound having at least one active hydrogen in one molecule. A resin curing agent for urethane paints. 21. The polyisocyanate according to claim 5.
A resin curing agent for urethane paints, wherein the isocyanate groups of the isocyanurate mixture are blocked by a compound having at least one active hydrogen per molecule. 22. The polyisocyanate according to claim 9.
A resin curing agent for urethane paints, characterized in that the isocyanate group of isocyanurate is blocked by a compound having at least one active hydrogen in one molecule. 23. A non-yellowing urethane paint resin composition containing the resin curing agent for urethane paints according to claim 20, 21 or 22. 24. Blocked with 2,5- or 2,6-diisocyanatomethylbicyclo[2,2,1]heptane or a mixture thereof and a compound having at least one active hydrogen in one molecule. A curing agent for powder coatings characterized by: 25. Blocked by a modified form of 2,5- or 2,6-diisocyanatomethylbicyclo[2,2,1]heptane and a compound having at least one active hydrogen in one molecule. A curing agent for powder coatings, which is characterized by: 26. An active isocyanate whose modified product is obtained by reacting 2,5- or 2,6-diisocyanatomethylbicyclo[2,2,1]heptane or a mixture thereof with water or a diol or polyol. The curing agent for powder coatings according to claim 25, which is a urethane polymer having a group. 27. The modified product is a polyisocyanate having an isocyanurate bond obtained by trimerizing 2,5- or 2,6-diisocyanatomethylbicyclo[2,2,1]heptane or a mixture thereof. The curing agent for powder coatings according to claim 25. [Claim 28] Claim 24, 25, 26 or 27
Contains the curing agent for powder coatings described above and a polyester polyol, and the composition ratio of the content is such that the blocks in the curing agent for powder coatings are dissociated at the baking temperature (isocyanate groups).
A polyester powder coating composition having an equivalent ratio of active hydrogen (H) of a polyester polyol (H/NCO group) to 0.8 to 1.3.