JP3056280B2 - Polyisocyanato-isocyanurate, method for producing the same, and uses thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to novel polyisocyanato-isocyanurates, to a process for their preparation and to their use. More specifically, the present invention relates to a polyisocyanato-isocyanurate having a novel structure and a method for producing the same, and a use of the polyisocyanato-isocyanurate for a curing agent, a resin, and a paint.

[0002]

2. Description of the Related Art Polyisocyanato-isocyanurate compounds in which some of the isocyanate groups of organic diisocyanates are trimerized, and methods for producing the same are known from many publications [see, for example, J. Am. Etch. Sanders and K.
C. Frisch: Polyurethane, Chemistry and Technology (1962) P.94 (JHSaund
ers and KC Frish: Polyuretanes, Chemistry and
Technology (1962) P.94)]. These polyisocyanato-isocyanurate compounds are widely used as raw materials for resins, foams, paints, films or adhesives. For example, the following equation (a)

Embedded image The hexamethylene diisocyanate nurate compound represented by the formula (1) is widely used as a resin for two-pack type urethane paint and its raw material.

[0003] Two-pack type urethane coating resins are already widely used as various coatings, using isocyanate compounds as curing agents and polyol compounds as main components. However, they have been developed with better performance. For example, a urethane-type polyisocyanate or polyisocyanurate-type isocyanate derived from tolylene diisocyanate as a curing agent, and an alkyd resin, a polyester polyol, an acrylic polyol or an epoxy polyol as a main component, the most typical of a general-purpose curing type Such two-component urethane paint resins are used in furniture and woodwork paints, as well as in corrosion-resistant paints called tar urethane paints.

However, urethane coatings using tolylene diisocyanate have high reactivity and excellent drying properties, but have extremely poor weather resistance. Therefore, for the purpose of improving weather resistance, polyisocyanate derived from an aliphatic or alicyclic compound such as hexamethylene diisocyanate, isophorone diisocyanate or 4,4′-dicyclohexamethylene diisocyanate is used. A two-component polyurethane coating resin mainly comprising an acrylic polyol or a polyester polyol as a curing agent has been devised. As such a resin for two-pack type polyurethane coating, an aliphatic polyisocyanate, for example, a urethane-type polyisocyanate derived from hexamethylene diisocyanate (hereinafter abbreviated as HDI), a buret-type polyisocyanate ( For example, USP 3,9
03,127), isocyanurate-type polyisocyanates (eg, USP 3,487,080, USP 4,412,073),
Urethane-type polyisocyanates derived from alicyclic polyisocyanates, for example, isophorone diisocyanate (hereinafter abbreviated as IPDI) (for example, DE 1,96
2,808) and isocyanurate-type polyisocyanates (for example, US Pat. No. 3,919,218). These have excellent characteristics such as weather resistance, flexibility, and abrasion resistance, and have established a firm position in, for example, the field of automobile repair and architectural exterior. However, since these aliphatic or alicyclic polyisocyanates have poor drying properties, two-part urethane coatings using these as a curing agent require a long time to sufficiently cross-link and form a tough coating film. Leave it still,
Or a forced drying method by baking had to be taken. However, due to poor heat resistance, yellowing is unavoidable during baking, and gloss is reduced.

Also, polyisocyanato-isocyanurate derived from HDI has poor compatibility with polyols, especially acrylic polyols, and two-pack type urethane coatings using these as a curing agent and a main component have high gloss, sharpness and sharpness. There is a disadvantage that the leveling property is reduced and the main agent used is limited. Furthermore, polyisocyanate derived from IPDI has low reactivity because the isocyanate group involved in the reaction is bonded to the secondary carbon, and the two-pack type urethane coating using this as a curing agent has poor drying properties. It had the drawback of becoming very bad. Still further, a polyisocyanato-isocyanurate obtained from a mixture of HDI and IPDI has been proposed (US Pat. No. 4,419,513). However, in IPDI,
One of the two isocyanate groups is highly reactive because it is bonded to a primary carbon, and the other isocyanate group is lowly reactive because it is bonded to a secondary carbon. When such IPDI is used in a cyclic trimerization reaction, a highly reactive isocyanate group reacts preferentially, leaving a less reactive isocyanate group. Therefore, HDI and IPDI
The polyisocyanato-isocyanurate obtained by trimerizing the above mixture has a disadvantage that the reactivity is low and the drying property is poor for urethane coatings. Even if the mixture in which the proportion of HDI is increased to improve the drying property is trimerized, the resulting polyisocyanato-isocyanurate has a drawback of yellowing when baked at a high temperature for urethane coatings. . Therefore, development of a two-pack type urethane coating resin having good weather resistance and excellent drying properties has been strongly desired.

Further, a so-called blocked isocyanate obtained by blocking an isocyanate group of an isocyanate compound with a blocking agent is used as a curing agent in a polyester-based powder coating material containing a polyester resin as a main component. In particular, a blocked isocyanate derived from IPDI is widely used as a polyester-based powder coating containing a polyester resin as a main component, for example, for use in precoated metal. However, when a blocked isocyanate derived from isophorone diisocyanate is used as a curing agent, a baking temperature of usually 200 ° C. or higher is required,
Even with a metal catalyst such as dibutyltin dilaurate, a baking temperature of 180 ° C. or higher was required. Therefore, a curing agent for polyester-based powder coatings having excellent low-temperature curability and weather resistance has been desired.

An object of the present invention is to provide a novel polyisocyanate useful for urethane coating resins and other uses.
It is to provide isocyanurates and mixtures thereof. A second object of the present invention is to provide a novel polyisocyanate-
It is an object of the present invention to provide a method for producing isocyanurates and mixtures thereof. A third object of the present invention is to provide a resin for urethane coatings using a novel polyisocyanate-isocyanurate mixture and having improved curability and drying properties, and a coating composition containing the resin. A fourth object of the present invention is to provide a curing agent for a polyester powder coating excellent in low-temperature curability and a polyester powder coating composition containing the curing agent.

The present inventors have studied various polyisocyanates containing isocyanurate groups of aliphatic diisocyanates in order to achieve the above object. As a result, a polyisocyanato-isocyanurate obtained from a mixture of the aliphatic diisocyanate represented by the general formula (3) and the polycyclic aliphatic diisocyanate represented by the general formula (4) and a mixture thereof are: For example, when used as a curing agent for urethane paints, the coating film has good weather resistance, good flexibility, and excellent curability, and has excellent drying properties. 6-diisocyanatomethylbicyclo [2,2,1] heptane and mixtures thereof,
Alternatively, an active hydrogen is added to the NCO group of the modified product in the molecule.
The inventors have found that a block isocyanate blocked with a blocking agent having at least one of them has an excellent effect as a curing agent for a polyester powder coating, and have completed the present invention.

That is, the present invention provides a compound represented by the general formula (1):

Embedded image [Wherein R ₁ , R ₂ and R ₃ represent an alkylene group having 2 to 12 carbon atoms or a compound represented by the formula (2)

Embedded image (Where k is 0 to 2, j and m are 1 to 5, h is 0 to 2)
Which represents an integer), which may be the same or different, and n represents an integer of 1 to 5]
A polyisocyanato-isocyanurate mixture containing two or more kinds of polyisocyanato-isocyanurate represented by

In the general formula (1), R ₁ and R ₂
And at least one of R ₃ is a group represented by the formula (2), and the rest is a substantially single polyisocyanato-isocyanurate having an alkylene group having 2 to 12 carbon atoms. Nato-isocyanurate or a mixture thereof (hereinafter, unless otherwise specified, a substantially single polyisocyanato-isocyanurate or polyisocyanato-isocyanurate mixture is simply referred to as polyisocyanato-isocyanurate) is represented by the general formula ( 3) OCN-
R ₄ —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):

Embedded image (Where k is 0 to 2, j and m are 1 to 5, h is 0 to 2)
Wherein the polycyclic aliphatic diisocyanate represented by the formula (1) is reacted by reacting the polycyclic aliphatic diisocyanate. The resin for non-yellowing type urethane paint containing this polyisocyanate-isocyanurate and this resin And a resin curing agent in which the isocyanate group of the polyisocyanate-isocyanurate is blocked by a blocking agent. Methylbicyclo [2,2
1] heptane, a mixture thereof, or a modified form thereof,
It is a curing agent for powder coatings containing a block isocyanate synthesized from a blocking agent having one or more active hydrogens in the molecule.

[0011]

According to the present invention, substantially independently of the present invention,
Certain polyisocyanato-isocyanurates or polyisocyanates
The soocyanato-isocyanurate mixture has the general formula
Polyisocyanato-isocyanurate represented by (1)
And more specifically, polyisocyanates
The to-isocyanurate mixture has the general formula (1)
And R₁, R_Two, R _ThreeAre the same or different, and n is 1 to 5
A polyisocyanana represented by the general formula (1)
A mixture containing two or more to-isocyanurates
And a substantially single polyisocyanato-
Socyanurate is represented by R in the general formula (1).₁, R_Two
And R_ThreeAt least one of the expressions (2)

Embedded image (Where k is 0 to 2, j and m are 1 to 5, h is 0 to 2)
Which is an integer), and the remainder is a group having 2 to 2 carbon atoms.
It is a polyisocyanato-isocyanurate having a substantially single structure in which 12 alkylene groups are present.

Such a polyisocyanate-isocyanurate mixture of the present invention is represented by the general formula (3) and the linear aliphatic diisocyanate (4) in the presence of a trimerization catalyst. Of a mixture with a 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) to the polycyclic aliphatic diisocyanate represented by the general formula (4) is about 1:
The mixture of 11 to 11: 1 is obtained by trimerizing a part of the isocyanate groups to obtain about 20 to 50% of the isocyanate groups originally present.
When is trimerized, a catalyst poison is immediately added to inactivate the trimerization catalyst to stop the trimerization reaction, and to remove unreacted diisocyanate by thin-film distillation as required.

The linear aliphatic diisocyanate used in the production method of the present invention has a general formula (3): OCN-R ₄ -NCO
(3) (wherein, R ₄ represents an alkylene group having 2 to 12 carbon atoms)
And 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-diisocyanatodecane, 1,11-diisocyanatoundecane, 1,12-diisocyanatododecane and the like. Among them, 1,6-diisocyanatohexane (Hexamethylene diisocyanate, HDI) is a particularly versatile linear aliphatic diisocyanate.

The polycyclic aliphatic diisocyanate used in this method has the general formula (4)

Embedded image (Where k is 0 to 2, j and m are 1 to 5, h is 0 to 2)
Where k = 0 means that there is no cross-linking).

Specifically, assuming that k = 0 and h = 0, 1,3-di (isocyanatomethyl) -cyclohexane, 1,4-di (isocyanatomethyl) -cyclohexane, 1,3-dihexane (Isocyanatoethyl) -cyclohexane, 1,4-di (isocyanatoethyl) -cyclohexane, 1-isocyanatomethyl-3 (4) -isocyanatoethyl-cyclohexane, 1-isocyanatomethyl-3 (4) -isocyanate Natopropyl-
Cyclohexane, 1-isocyanatomethyl-3 (4) -isocyanatobutyl-cyclohexane, 1-isocyanatomethyl-3 (4) -isocyanatopentyl-
Cyclohexane, 1-isocyanatoethyl-3 (4) -isocyanatopropyl-
Cyclohexane, 1-isocyanatoethyl-3 (4) -isocyanatobutyl-cyclohexane, 1-isocyanatomethyl-3 (4) -isocyanatopentyl-
Cyclohexane and the like.

Assuming that k = 0 and h = 1, 3 (4), 7 (8) -di (isocyanatomethyl) bicyclo [4,3,0
^1,6 ] nonane, 3 (4) -isocyanatomethyl-7 (8) -isocyanatoethylbicyclo [4,3,0 ^1,6 ] nonane, 3 (4) -isocyanatoethyl-7 (8)- Isocyanatomethylbicyclo [4,3,0 ^1,6 ] nonane, 3 (4) -isocyanatomethyl-7 (8) -isocyanatopropylbicyclo [4,3,0 ^1,6 ] nonane, 3 (4) -Isocyanatopropyl-7 (8) -isocyanatomethylbicyclo [4,3,0 ^1,6 ] nonane, 3 (4) -isocyanatomethyl-7 (8) -isocyanatobutylbicyclo [4,3,0 ^1,6 ] nonane, 3 (4) -isocyanatobutyl-7 (8) -isocyanatomethylbicyclo [4,3,0 ^1,6 ] nonane, 3 (4) -isocyanatomethyl-7 (8)- Isocyanatopentylbicyclo [4,3,0 ^1,6 ] nonane, 3 (4) -isocyanatopentyl-7 (8) -isocyanatomethylbicyclo [4,3,0 ^1,6 ] nonane, 3 (4) , 7 (8) -Di (isocyanatoethyl) bicyclo [4,3,0
^1,6 ] nonane, 3 (4) -isocyanatoethyl-7 (8) -isocyanatopropylbicyclo [4,3,0 ^1,6 ] nonane, 3 (4) -isocyanatopropyl-7 (8)- Isocyanatoethylbicyclo [4,3,0 ^1,6 ] nonane, 3 (4) -isocyanatoethyl-7 (8) -isocyanatobutylbicyclo [4,3,0 ^1,6 ] nonane, 3 (4) -Isocyanatobutyl-7 (8) -isocyanatoethylbicyclo [4,3,0 ^1,6 ] nonane, 3 (4) -isocyanatoethyl-7 (8) -isocyanatopentylbicyclo [4,3,0 ^1,6 ] nonane and 3 (4) -isocyanatopentyl-7 (8) -isocyanatoethylbicyclo [4,3,0 ^1,6 ] nonane.

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-isocyanatomethyl-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.

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-isocyanatomethyl-5 (6) -isocyanatopentylbicyclo [2,2,2] octane, 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 and the like.

Assuming that k = 1 and h = 1, 3 (4), 8 (9) -di (isocyanatomethyl) tricyclo [5,
2,1,0 ^2,6 ] decane, 3 (4) -isocyanatomethyl-8 (9) -isocyanatoethyltricyclo [5,2,1,0 ^2,6 ] decane, 3 (4) -isocyanate Natomechiru -8 (9) - isocyanatopropyltrimethoxysilane cyclo [5,2,1,0 ^{2, 6]} decane, 3 (4) - isocyanatomethyl-8 (9) - isocyanatobutyl tricyclo [5,2 , 1,0 ^2,6 ] decane, 3 (4) -isocyanatomethyl-8 (9) -isocyanatopentyltricyclo [5,2,1,0 ^{2 , 6} ] decane, 3 (4), 8 ( 9) -Di (isocyanatoethyl) tricyclo [5,
2,1,0 ^2,6] decane, 3 (4) - isocyanatoethyl -8 (9) - isocyanatopropyltrimethoxysilane cyclo [5,2,1,0 ^{2, 6]} decane, 3 (4) - isocyanatomethyl Natoechiru -8 (9) - isocyanatobutyl tricyclo [5,2,1,0 ^2,6] decane, 3 (4) - isocyanatoethyl -8 (9) - isocyanatomethyl pen tilt Li cyclo [5,2 , 1,0 ^{2 , 6} ] decane.

Among these various kinds of polycyclic aliphatic diisocyanates, particularly preferred is 2,5 (6) -di (isocyanatomethyl) bicyclo [2,2,1] heptane (hereinafter referred to as BC
HI) and 3 (4), 8 (9) -di (isocyanatomethyl) tricyclo [5,2,1,0 ^2,6 ] decane (hereinafter TCDI)
Abbreviated).

These compounds are described, for example, in DE P3,01
8,198.7, DE-OS 1,645,595 and DE-A-2,819,980. In the general formula (4), as a method for synthesizing a compound with h = 1, j = 1 and k = 1, hydroformylation from dimerized cyclopentadiene, reductive amino compound and phosgene US Pat. No. 3,143,570 discloses a method of synthesizing a compound of h = 0, j = 1 and k = 1 according to a method of phosgenation of a corresponding diamine. Can be manufactured.

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 in a molar ratio. In the range of 1:11 to 11: 1. A mixture in a molar ratio in this range is used as a raw material diisocyanate. Polyisocyanate obtained by reacting in this range
Isocyanurate is a transparent viscous resinous liquid, and its viscosity changes depending on the composition ratio of the raw materials. For example, starting materials BCHI and HDI exhibit fluidity at room temperature within this molar ratio range, and BCHI / HDI in this range.
The polyisocyanato-isocyanurate obtained from the composition ratio has high fluidity and heat stability.

In order to carry out the present invention, a diisocyanate mixture in which the raw material linear aliphatic diisocyanate and polycyclic aliphatic diisocyanate are mixed within the above range is prepared using a trimerization catalyst. , A so-called trimerization reaction. As the trimerization catalyst used in the present invention, for example,
Tetraalkylammonium hydroxides such as tetramethylammonium, tetraethylammonium and tetrabutylammonium, and organic weak acid salts, and hydroxyalkylammonium hydroxides such as trimethylhydroxypropylammonium, trimethylhydroxyethylammonium, triethylhydroxypropylammonium and triethylhydroxyethylammonium And organic weak acid salts, alkali metal salts of alkyl carboxylic acids such as acetic acid, caproic acid, octylic acid, and myristic acid, and metal salts such as tin, zinc, and lead; compounds containing an aminosilyl group such as hexamethyldisilazane; triethylamine and tributylamine , N, N-dimethylaniline, N
-Ethylpiperidine, N, N'-dimethylpiperazine, Mannich salts of phenol compounds, tertiary amines such as N, N ', N "-tris (dimethylaminopropyl) -hexahydro-sym-triazine and the like.

In particular, trimerization catalysts using a combination of an alkali metal salt of a carboxylic acid and a polyalkylene oxide compound or an alcohol are preferred, and these catalysts exhibit excellent effects in reactivity, reaction controllability and the like. Examples of the alkali metal carboxylate include alkali metal formate, alkali metal acetate, alkali metal propionate, alkali metal octanoate, and alkali metal benzoate, and preferably potassium acetate. Examples of the polyalkylene oxide compound include polyethylene glycol or polypropylene glycol having a molecular weight of about 200 to 3000, and preferably polyethylene glycol having an average molecular weight of 400. As the alcohol, alcohols such as 2-ethylhexanol may be used.

The method for using these as a trimerization catalyst is not particularly limited. For example, usually, an alkali metal carboxylate is used in a state of being dissolved in a polyalkylene oxide compound or an alcohol. The amount of the trimerization catalyst used is 0.0001 to 0.001 to the raw material diisocyanate mixture.
It is in the range of 5% by weight, preferably 0.001 to 2% by weight.
In the reaction, alcohols such as ethylene glycol, 1,3-butanediol, neopentyl glycol, 2-ethyl-1,3-hexanediol, trimethylolpropane, polypropylene glycol and phenol are used as a co-catalyst. Is also good. These alcohols can be added simultaneously with the isocyanurate-forming catalyst, or they can be reacted with diisocyanate as a raw material in advance to form a urethane bond, and then be transferred to an isocyanurate-forming step. In particular, ethylene glycol, 1,3-butanediol, neopentyl glycol, 2-ethyl-1,3-hexanediol, 2,2,
Polyhydric alcohols such as 4-trimethyl-1,3-pentanediol and trimethylolpropane can also be used as polyisocyanurate modifiers. These cocatalysts
What is necessary is just to use it in the amount substantially the same as a trimerization catalyst.

The reaction may or may not use a solvent. When a solvent is used, a solvent having no reaction activity for the isocyanate group is used. The reaction temperature is usually
It is in the range of 20-120 ° C, preferably in the range of 50-90 ° C.
The reaction is preferably performed in 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 residual amount of the unreacted raw material by gas chromatography.
In general, if the conversion reaction proceeds excessively, the viscosity of the product increases, and the compatibility with the polyol decreases.Therefore, a method of reducing the conversion rate of the reaction, leaving unreacted raw materials, stopping the reaction, and removing the reaction is carried out. Will be The reaction conversion is usually
It should be 30-80% by weight.

Once the reaction has reached the desired conversion, for example, hydrogen chloride, sulfuric acid, phosphoric acid, p-toluenesulfonic acid,
An acid such as trifluorosulfonic acid or a catalyst deactivator such as benzoyl chloride or acetyl chloride is added to stop the reaction. The addition amount is preferably in the range of 1.0 to 1.5 times the equivalent of neutralizing the alkali metal salt of carboxylic acid. When the trimerization reaction is stopped, unreacted diisocyanate is mixed,
It is an almost colorless low viscosity liquid. After stopping the reaction, the deactivated catalyst is removed from the reaction mixture as necessary, and then the unreacted raw materials and the solvent used are removed. The unreacted raw material or the solvent is separated by, for example, a thin-film distillation method or a solvent extraction method to obtain the desired polyisocyanato-isocyanurate. At this time, it is preferable to remove the unreacted diisocyanate in the target product so as to have a content of about 1% by weight or less. Whether the desired polyisocyanato-isocyanurate is obtained as a substantially single polyisocyanato-isocyanurate or as a polyisocyanato-isocyanurate mixture is selected depending on the intended use, and is substantially selected. In order to obtain a single polyisocyanate-isocyanurate, there is a method of fractionation by GPC. The viscosity of the polyisocyanate-isocyanurate mixture depends on the molar ratio of the starting isocyanate. For example, starting materials HDI and BCH
If the molar ratio of I is about 1:11 to 11: 1, it shows fluidity at room temperature.

There is no particular limitation on the apparatus for performing the trimerization reaction, but a reactor equipped with a thermometer, a nitrogen gas inlet, and a cooling pipe so that the inside of the reaction solution is sufficiently stirred is preferable. .

The polyisocyanato-isocyanurate thus obtained, which has a substantially single specific structure and a mixture of two or more structures, comprises a non-yellowing urethane coating resin curing agent, Used as a raw material for resins and coating compositions. The resulting polyisocyanate-isocyanurate mixture is optionally blocked with an isocyanate group with a blocking agent, and then mixed with an active hydrogen-containing compound to form a two-part heat-resistant, non-yellowing type excellent in weatherability. It can also be a resin for urethane paint. As the blocking agent to be used, compounds having one or more active hydrogens in the molecule, for example, 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; Dimethyl malonate,
Active methylenes such as diethyl malonate and ethyl acetoacetate, butyl mercaptan, thiophenol, tert-
Mercaptans such as dodecyl mercaptan, ε-caprolactam, acetanilide, acetanisidine, acetate amide, acid amides such as benzamide, succinimide,
Imides such as maleic imide; amines such as diphenylamine, phenylnaphthylamine, aniline and carbazole; imidazoles such as imidazole and 2-ethylimidazole; ureas such as urea, thiourea and ethylene urea; phenyl N-phenylcarbamate , Carbamates such as 2-oxazolidone, imines such as ethyleneimine, oximes such as formaldoxime, acetoaldoxime, methylethylketoxime and cyclohexanone oxime, and sulfites such as sodium bisulfite and potassium bisulfite. These compounds can be appropriately selected and used according to the purpose and application. These may be used alone or as a mixture. The blocking of the isocyanate group by these blocking agents is performed by mixing a polyisocyanato-isocyanurate and a blocking agent having an approximately equivalent ratio with the polyisocyanate during the production of a curing agent for a paint,
This is achieved by heating and stirring to about 130 ° C.

The non-yellowing type urethane coating resin of the present invention comprises:
It is derived from the polyisocyanato-isocyanurate represented by the above general formula (1) or the polyisocyanato-isocyanurate obtained by blocking the NCO group and a compound having at least two or more active hydrogens. Resin. The compound containing at least two active hydrogens used for forming the resin includes a compound containing at least two active hydrogens in one molecule and a polymer. Specifically, ethylene glycol, propylene glycol, β, β′-dihydroxydiethyl ether (diethylene glycol), dipropylene glycol, 1,4-butylene glycol, 1,3-butylene glycol, 1,6-hexamethylene glycol, Glycols such as neopentyl glycol, polyethylene glycol, polypropylene glycol, polypropylene-polyethylene glycol, and polybutylene glycol;
Alkane polyols such as glycerin, trimethylolpropane, hexanetriol, pentaerythritol, xylitol, and sorbitol; alkylene oxides (eg, ethylene oxide,
Propylene oxide, 1,2-butylene oxide, etc.)
Polyether polyols obtained by adding a single compound or a mixture thereof, such as polyether polyols obtained by reacting a polyfunctional compound such as ethylenediamine or ethanolamine with an alkylene oxide; dibasic acid (for example, succinic acid) Acid, adipic acid, sebacic acid, dimer acid, maleic anhydride, phthalic anhydride,
Isophthalic acid, a single or mixture selected from the group consisting of carboxylic acids such as terephthalic acid) and polyhydric alcohols (for example, ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol,
1, 4-butylene glycol, 1,3-butylene glycol, 1,6-hexamethylene glycol, neopentyl glycol, glycerin, trimethylolpropane, etc., alone or in a mixture thereof). Polyol resins;
Acrylic polyol resins obtained by copolymerizing a polymerizable monomer having one or more active hydrogens in one molecule and another monomer copolymerizable therewith, specifically, for example, (a) active hydrogen-containing Acrylates (eg, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxybutyl acrylate, etc.), methacrylates containing active hydrogen (eg, 2-hydroxyethyl methacrylate, methacrylic) Acid-2-hydroxypropyl, methacrylic acid-
2-hydroxybutyl) or glycerin monoester or methacrylate monoester, trimethylolpropane acrylate monoester or methacrylate monoester alone or as a mixture of (b) acrylic acid Esters (for example, methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, etc., methacrylic esters (for example, methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, methacryl Acid n-butyl, isobutyl methacrylate, n-hexyl methacrylate,
And / or (c) unsaturated carboxylic acids (eg, acrylic acid, methacrylic acid, maleic acid, itaconic acid, etc.), unsaturated amides (eg, acrylamide,
N-methylol acrylamide, diacetone acrylamide, etc.) and other polymerizable monomers (eg, glycidyl methacrylate, styrene, vinyltoluene, vinyl acetate, acrylonitrile, etc.) are obtained by polymerizing with a single or a mixture thereof. Acrylic polyol resins: novolak type, β-methyl epichloro type, cyclic oxirane type, glycidyl ether type, glycidyl ester type, glycol ether type, epoxidized fatty acid unsaturated compound, epoxidized fatty acid ester type, polycarboxylic acid ester type And epoxy resins such as aminoglycidyl type, halogenated type and resorcinol type, and monosaccharides such as fructose, glucose, sucrose, lactose and 2-methylglycoxide or derivatives thereof, trimethylolbenzene, tris ( - aromatic or heterocyclic aliphatic polyvalent alcohol such as hydroxyethyl) isocyanurate. These may be used as a mixture, and further, these and other compounds containing two or more active hydrogens, for example, a compound containing a primary or secondary amino group (eg, 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 (eg, N, N′-dimethylurea, N-methyl-N′-cyclohexylurea), thiol group-containing compounds (eg, 1,2-ethanedithiol, 1,6-hexane) Dithiol, polyether polythiol, polyester polythiol, etc.), a carboxyl group-containing compound (eg, succinic acid, adipic acid, sebacic acid, terephthalic acid, carboxyl group-terminated polybutadiene) or 1
One or more compounds selected from compounds containing different active hydrogen-containing groups in the molecule (for example, monoethanolamine, thioethanolamine, lactic acid, β-alanine, etc.) can be mixed and used. As described above, various active hydrogen-containing compounds have been specifically exemplified, but the active hydrogen-containing compound of the present invention is not limited thereto, and isocyanato-isocyanurate used for the non-yellowing urethane coating resin of the present invention. Any active hydrogen-containing compound capable of reacting to form a urethane resin can be used, and various combinations can be selected. Among the active hydrogen-containing compounds exemplified above, methyl ethyl ketoxime is preferably used frequently.

In the formation of the non-yellowing urethane coating resin of the present invention, the compound containing at least two active hydrogens and the isocyanato-isocyanurate are combined with active hydrogen / NC
The O equivalent ratio is in the range of 0.5 to 2, preferably 0.8 to 1.2. In forming the non-yellowing urethane coating resin of the present invention, a compound containing at least two active hydrogens and an isocyanato-isocyanurate together with an appropriate solvent, if necessary, for example, hydrocarbons (for example,
Benzene, toluene, xylene, cyclohexane, mineral spirit, naphtha, etc., ketones (eg, acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.), esters (eg, ethyl acetate, n-butyl acetate, cellosolve acetate, isobutyl acetate, etc.) These solvents can be appropriately selected and used according to the purpose and application. These solvents may be used alone or as a mixture. Further, various additives used in the technical field such as a catalyst, a pigment, a leveling agent, an antioxidant, a flame retardant, a plasticizer, and a surfactant can be mixed and used according to the purpose and application.

In an embodiment of forming the non-yellowing urethane coating resin according to the present invention, a polyisocyanate-isocyanurate and an active hydrogen-containing compound, and a solvent or an additive depending on the purpose and application are used immediately before the formation of the polyurethane resin. In addition, a composition is prepared and a resin is usually formed at a temperature in the range of room temperature to 150 ° C. to obtain a composition containing the resin, or a so-called block in which the NCO group of polyisocyanato-isocyanurate is blocked with a blocking agent. Isocyanato-isocyanurate active hydrogen-containing compound, depending on the purpose and use solvent, catalyst, pigment, leveling agent,
A composition is prepared by blending various additives used in the technical field such as an antioxidant, a plasticizer and a surfactant.
By forming the resin at a temperature in the range of 100 ° C. to 250 ° C., a composition containing the resin can be obtained. When the non-yellowing type urethane paint resin of the present invention is used as a paint, a metal,
Excellent adhesion to coated objects such as plastic, rubber, leather, concrete, etc.
It can be used for a wide range of applications as a paint for building materials and woodwork.

Further, the curing agent for powder coating materials included in the present invention contains 2,5- and / or 2,6-diisocyanatomethylbicyclo [2,2,1] heptane, or a modified product thereof, in a molecule. It is a blocked isocyanate synthesized from a blocking agent having at least one active hydrogen, and a powder coating obtained using this is excellent in low-temperature curability and also in weather resistance. Used in the powder coating curing agent of the present invention
2,5- and / or 2,6-diisocyanatomethylbicyclo [2,
2,1] heptane (hereinafter abbreviated as BCHI)
5-diisocyanatomethylbicyclo [2,2,1] heptane,
2,6-diisocyanatomethylbicyclo [2,2,1] heptane represents a single compound or a mixture thereof, and a modified form thereof. As the modified product, a urethane prepolymer having an active isocyanate group at a terminal obtained by reacting excess BCHI with water, a diol or a polyol, or a polyisocyanate having an isocyanurate bond obtained by trimerizing BCHI is suitable. is there. Particularly preferred are polyisocyanates obtained by trimerizing BCHI. Further, a mixture containing a residual monomer in these modified products may be used.

Examples of the diols or polyols used for synthesizing the urethane prepolymer having an active isocyanate group at the terminal include ethylene glycol, diethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, and the like.
Polypropylene glycol, 1,3-butanediol,
Examples thereof include diols such as 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, and 3-methylpentanediol, and polyols such as trimethylolpropane, glycerin, polyester polyol, and epoxy polyol.

Further, in addition to the above-mentioned BCHI or a modified form thereof, a combination with other known isocyanates is also possible. In this case, it is necessary to synthesize the urethane prepolymer such that the terminal of the urethane prepolymer is BCHI from the viewpoint of low-temperature curability. Other known isocyanates that can be used in combination include, for example, aliphatic or alicyclic diisocyanates such as isophorone diisocyanate (IPDI) and hexamethylene diisocyanate (HDI) or tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MD
Aromatic diisocyanate such as I), or a modified product such as an aliphatic or alicyclic diisocyanate or a modified urethane, carbodiimide, isocyanurate, or adduct of an aromatic diisocyanate; crude TDI; polymethylene polyphenylene And polyisocyanates such as polyisocyanate (polymeric MDI).

Further, at least one active hydrogen is contained in one molecule.
Examples of the blocking agent having 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 coating of the present invention,
The above-mentioned BCHI, a modified form thereof, or a mixture thereof and a blocking agent having at least one active hydrogen in one molecule are synthesized by an ordinary method. The obtained curing agent for powder coating can be used as powder coating by blending polyester polyol and other additives.

The polyester powder coating composition of the present invention is a composition comprising the above-mentioned powder coating curing agent and a polyester polyol. , The isocyanato-isocyanurate blocking agent in which the NCO group is blocked comes off at the baking temperature and dissociates the isocyanate group (NC
The composition has an equivalent ratio (H / NCO group) of the active hydrogen (H) of the polyester polyol to the O group) of 0.8 to 1.3, preferably 0.9 to 1.2. The above-mentioned polyester polyols include the above-mentioned diols or polyols and polybasic acids such as phthalic anhydride, isophthalic acid, terephthalic acid, dimethyl terephthalic acid, adipic acid, azelaic acid, sebacic acid, and trimellitic anhydride. To a polybasic acid used for polyester synthesis. The polyester polyol used in the present invention needs to have a hydroxyl group at the terminal of the molecule, and needs to be synthesized under the condition that the concentration of the hydroxyl group in the molecule is excessive with respect to the concentration of the carboxyl group.

The polyester powder coating composition of the present invention contains, in addition to the polyester polyol, for example, inorganic pigments such as titanium oxide, barium sulfate, calcium carbonate, iron oxide, and talc, phthalocyanine blue, phthalocyanine green, and carbon black. No additional matter can be added even if organic pigments such as the above, and additional materials such as a surface preparation agent, an ultraviolet absorber, an antioxidant, and a curing catalyst are added. Conventionally, this type of powder coating required a baking temperature of 180 ° C or higher even with a curing catalyst combined system, but by using the powder coating curing agent of the present invention, low-temperature baking at 160 ° C became possible. And a coating film having excellent weather resistance is obtained.

[0039]

The polyisocyanato-isocyanurate of the present invention shows fluidity even at room temperature in a solid content of 100%, that is, in a solvent-free state, and has good workability. High NCO
It has a content and can reduce the amount of isocyanate used for the polyol. It has good thermal stability derived from isocyanate groups, and harmful isocyanate monomers are rarely generated by decomposition. It has features such as having a stable polycyclic structure of the skeleton. Also,
The production method is a method capable of efficiently obtaining a target polyisocyanate-isocyanurate or a mixture thereof by a simple method with good selectivity.

Polyurethane coatings using this polyisocyanato-isocyanurate as a curing agent generally have a good balance between adhesion to various substrates, hardness and flexibility, crack resistance, water resistance, chemical resistance, gloss, It has excellent weather resistance, light stability, and heat stability, as well as excellent appearance. That is, the polyisocyanate-isocyanurate of the present invention has, for example, higher reactivity and heat resistance than aliphatic isocyanate-polyisocyanurate derived from hexamethylene diisocyanate. The non-yellowing type urethane coating resin has fast initial curing and drying properties, and greatly improves yellowing during baking. Further, it has good compatibility, excellent appearance, and the coating film performance is equal to or higher than that of a commercially available product, so that it is suitable for applications where emphasis is placed on workability such as vehicle coating, appearance and coating film performance.

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, a conventional curing catalyst combination system cannot be used. Although a baking temperature of 180 ° C or higher was required, low-temperature baking at 160 ° C is possible and the weather resistance is excellent.

[0042]

EXAMPLES The present invention will be described more specifically with reference examples, examples and comparative examples. However, the present invention is not limited to these specific examples. The percentages described in these examples are all percentages by weight.

Reference Example 1 Production of 2,5 (6) -diisocyanatomethyl-bicyclo [2.2.1] heptane (hereinafter abbreviated as BCHI) 687 g of isoamyl acetate and orthodichlorobenzene (hereinafter abbreviated as ODCB) as solvents. 2189 g), and prepared as a solvent for salt formation and phosgenation (hereinafter, referred to as a mixed solvent). The ratio of ODCB in this mixed solvent was 76.1.
%. 1126 g of the mixed solvent was put into a 3 l four-necked flask, and cooled to 5 ° C. with ice water while stirring. After blowing hydrogen chloride gas at a rate of 1.6 Nl / min for 30 minutes, diaminomethyl-bicyclo [2,2,1]
A solution of 250.0 g (1.62 mol) of a mixture of about 60% of 2,5-isomer and about 40% of 2,6-isomer of heptane (hereinafter abbreviated as BCHA) in 1750 g of a mixed solvent (raw material diamine concentration: 12.5%) was dropped into the liquid in the flask over 2 hours. The temperature inside the flask was maintained at 10 to 15 ° C while cooling was continued during the dropwise addition. The blowing of hydrogen chloride gas was continued at a rate of 1 Nl / min. After the dropping of the raw material diamine solution was completed, the blowing of hydrogen chloride gas was continued at a rate of 0.4 Nl / min for 2 hours while keeping the temperature in the flask at 25 ° C. or lower to complete the salt formation reaction. The salt formation reaction proceeded extremely smoothly without generating agglomerates of hydrochloride particles, and a slurry of white uniform fine particles was obtained. After completion of the salt-forming reaction, the temperature in the flask was raised from 25 ° C. to 160 ° C. in 50 minutes, and phosgene was gradually blown in from 100 ° C. to start the phosgenation reaction. Internal temperature with mantle heater 1
While adjusting to 60 ± 1 ° C, blow phosgene 100 ~
Continued at a rate of 120 g / h. About 6 hours after the start of the phosgene injection, the reaction solution changed from a white slurry to a clear orange-red color.
After blowing at a rate of g / h, the phosgenation reaction was terminated. The phosgenation reaction time was 6.5 hours in total. The phosgene gas used was about 2.2 times the theoretical amount. Thereafter, N ₂ gas was blown into the reaction solution in the flask at a rate of 1.3 Nl / min for 80 minutes to perform degassing. During this time, the liquid temperature
160 ± 1 ° C. The reaction solution was degassed, cooled and filtered with a filter paper (5C) to remove a trace amount of solids. After removing the solvent from the filtrate, rectification under vacuum is performed at 110 to 116 ° C / 0.4 to 0.6.
306.5 g of the main fraction of torr was obtained. The analysis of this product was as follows. NCO% 40.72 Hydrolysable chlorine 0.032% Gas chromatographic purity% 99.8 Hydrolysable 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 and the like.
The yield of the main fraction is the theoretical value (1.62 mol, 334.2 g)
Was 91.7%.

Example 1 Production of polyisocyanate-isocyanurate by cyclotrimerization of a mixture of 1,6-hexamethylene diisocyanate (hereinafter sometimes abbreviated as HDI) and BCHI Catalyst mixture (hereinafter catalyst) Preparation of A) Abbreviation was made by dissolving 1.0 g of dried anhydrous potassium acetate in 9 g of polyethylene glycol having an average molecular weight of 400. Production of polyisocyanate-isocyanurate by cyclotrimerization 100 g of 1,6-hexamethylene diisocyanate (0.4 g) was placed in a four-necked flask equipped with a thermometer, a cooling pipe, a nitrogen introduction pipe, and a stirring blade.
595 mol), 100 g (0.485 mol) of BCHI and catalyst A
1.6 g was added, and the temperature was raised to 80 ° C. After 2.5 hours, the NCO content decreased from 45.35% to 24.3%, so benzoyl chloride
0.25 g was added, and the mixture was stirred at 60 ° C. for 1 hour to deactivate the trimerization catalyst A. A slightly viscous transparent viscous liquid was obtained. The reaction mass thus obtained was subjected to thin film distillation under a vacuum of 0.2 torr to remove 110 g of a polyisocyanate-isocyanurate mixture by removing unreacted raw materials. This is butyl acetate 11
Polyisocyanate having the following resin constant dissolved in 0 g
A solution of isocyanurate was obtained. Resin constant The ratio of the methyl carbamate compound obtained by reacting a part of this solution with methyl alcohol was as follows by gel permeation chromatography (hereinafter referred to as GPC analysis). From this GPC analysis, it was almost impossible to produce a high polymer having n = 6 or more, and it was possible to produce a polyisocyanate-isocyanurate containing at least 30% by weight of n = 1. Furthermore, the aforementioned methyl carbamate compound is newly added to G
Each component was fractionated on a PC. N = 1 body (3
NMR spectrum, FD-
The MS spectrum was measured and analyzed. In the analysis, the spectrum of n = 1 isomer (trimer) obtained by fractionating the methyl carbamate compound of the BCHI monomer single trimer by GPC was referred to. The mass numbers 600, 638, 676, and 714 were detected from the FD-MS spectrum. This is BCH
I and HDI alone trimerized and BCHI
And HDI correspond to the molecular weight of the trimerized compound at a molar ratio of 2: 1 and 1: 2, respectively. From the above analysis results, it was found that the compound represented by the formula (1) was obtained. In the ¹³ C-NMR spectrum, the signal of methylene carbon of HDI (26.7 ppm, 30 ppm, 41 ppm) and BCH
Carbon signal of the bicyclo ring of I (28 ppm to 47 ppm) and carbon signal of the carbonyl group of the trimer ring (150 ppm
) Are observed separately from each other, so that ¹³ C-NM
The composition ratio between BCHI and HDI can be determined from the NNE mode of R.

Example 2 Production of polyisocyanato-isocyanurate by cyclotrimerization of a mixture of 1,6-hexamethylene diisocyanate and BCHI Four-necked flask with thermometer, cooling tube, nitrogen inlet tube, stirring blade To the mixture were added a mixture of 140 g (0.832 mol) of HDI and 60 g (0.291 mol) of BCHI and 1.5 g of Catalyst A, and the temperature was raised to 80 ° C. After 4.0 hours, the NCO content decreased from 47.2% to 36.4%, so 0.114 g of benzoyl chloride was added, and the mixture was stirred at 60 ° C. for 1 hour to deactivate the trimerization catalyst A. A slightly viscous transparent viscous liquid was obtained. The reaction mass obtained in this way was subjected to thin-film distillation under a vacuum of 0.2 torr to remove unreacted raw materials.
65 g of a polyisocyanato-isocyanurate mixture were obtained. This was dissolved in 65 g of butyl acetate to obtain a solution of polyisocyanato-isocyanurate having the following resin constants.

Example 3 Production of polyisocyanato-isocyanurate by cyclotrimerization of a mixture of 1,6-hexamethylene diisocyanate and BCHI In a four-necked flask equipped with a thermometer, a cooling pipe, a nitrogen introduction pipe, and a stirring blade 1.6 g of a mixture of 180 g (1.070 mol) of HDI and 20 g (0.097 mol) of BCHI and 1.6 g of catalyst A were added, and the temperature was raised to 80 ° C. After 4.0 hours, the NCO content decreased from 49.1% to 34.7%, so 0.114 g of benzoyl chloride was added, and the mixture was stirred at 60 ° C. for 1 hour to deactivate the trimerization catalyst A. A slightly viscous transparent viscous liquid 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.
g of a polyisocyanato-isocyanurate mixture were obtained. This was dissolved in 72 g of butyl acetate to obtain a solution of polyisocyanato-isocyanurate having the following resin constants.

Example 4 180 g (1.144 mol) of BCHI, 20 g (0.119 mol) of HDI
The reaction was carried out in the same manner as in Example 2 except for using. NCO
The content decreased from 41.7% to 31.5%. Benzoyl chloride was used in an amount of 0.114 g as a catalyst poison. After thin film distillation, residual BC
HI 0.01%, residual HDI trace amount, NCO content 17.5%,
86 g of a polyisocyanate-isocyanurate mixture having a viscosity of 36,000 cps / 25 ° C. were obtained.

Example 5 As in Example 1, 100 g (0.406 mol) of TCDI and H
1.5 g of catalyst A in a mixture of 100 g (0.594 mol) of DI
After the addition, the temperature was raised to 80 ° C., and the reaction was performed for 4 hours. NC
The O content decreased from 42.1% to 33.7%. 0.21 g of benzoyl chloride was added and reacted at 60 ° C. for 1 hour. The unreacted diisocyanate monomer was removed from the product by a thin film distillation apparatus under a vacuum of 0.2 torr. 73 g of a polyisocyanate-isocyanurate mixture having a residual TCDI of 0.40%, a residual HDI of 0.01% or less and an NCO content of 16.5% were obtained.

Example 6 60 g (0.244 mol) of TCDI and 140 g (0.832 mol) of HDI
The reaction was carried out in the same manner as in Example 5, except for using. NCO
The content decreased from 45.2% to 34.9%. Benzoyl chloride was used in an amount of 0.114 g as a catalyst poison. After thin film distillation, residual TC
DI 0.40%, residual HDI 0.01% or less, NCO content 1
7.3% polyisocyanate-isocyanurate mixture 66
g was obtained.

Example 7 As in Example 1, 20 g (0.097 mol) of BCHI and TC
20 g (0.080 mol) of DI and 160 g (0.832 mol) of HDI
1.5 g of Catalyst A was added to the mixture, and the temperature was raised to 80 ° C., followed by a reaction for 4 hours. NCO content from 47.2% to 36.1%
Down to. Add 0.114 g of benzoyl chloride and add 1 at 60 ° C.
A time reaction was performed. The unreacted diisocyanate monomer was removed from the product by a thin film distillation apparatus under a vacuum of 0.2 torr. Residual BCHI 0.10%, residual TCDI 0.30%, residual H
68 g of a polyisocyanate-isocyanurate mixture having a DI of 0.01% or less and an NCO content of 19.0% were obtained.

Example 8 50 g (0.242 mol) of BCHI and 50 g (0.203 mol) of TCDI
The reaction was carried out in the same manner as in Example 7 except that 100 g (0.594 mol) of HDI was used. NCO content from 43.7% to 34.1%
Decreased to. Benzoyl chloride was used in an amount of 0.114 g as a catalyst poison. After thin film distillation, residual BCHI 0.10%, residual TCDI
0.40%, residual HDI 0.01% or less, NCO content 16.9
% Polyisocyanate-isocyanurate mixture
was gotten.

Example 9 Production of polyisocyanato-isocyanurate by cyclotrimerization of BCHI 200 g (0.97 mol) of BCHI and 1.5 g of catalyst A were added to a four-necked flask equipped with a thermometer, a cooling tube, a nitrogen inlet tube, and a stirring blade. The temperature was raised to 80 ° C. 2.0 hours later, NC
Since the O content decreased from 40.7% to 30.5%, 0.114 g of benzoyl chloride was added, and the mixture was stirred at 60 ° C. for 1 hour and the trimerization catalyst A was added.
Was deactivated. A slightly viscous transparent viscous liquid 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, to obtain 80 g of a polyisocyanate-isocyanurate mixture. This was dissolved in 80 g of butyl acetate to obtain a polyisocyanate-isocyanurate solution having the following resin constants.

Comparative Example 1 Production of polyisocyanate-isocyanurate by cyclotrimerization 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 inlet tube, and a stirring blade. 1.5 g of a mixture of 100 g (0.59 mol) 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. 4.0 hours later, NCO
Benzoyl chloride 0.215g as content decreased to 34.7%
, And stirred at 60 ° C. for 1 hour to deactivate the trimerization catalyst A. A slightly viscous transparent viscous liquid 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, whereby 82 g of a polyisocyanato-isocyanurate mixture was obtained. This was dissolved in 82 g of butyl acetate to obtain a polyisocyanate-isocyanurate solution having the following resin constants.

Example 10 (Blocking reaction) 19.6 g (0.231 mol) of methyl ethyl ketoxime was added to 100 g of the polyisocyanate-isocyanurate obtained in the same manner as in Example 1, and the mixture was stirred at 80 ° C for 3 hours. The rate was 0.02%. This was cooled to obtain block urethane having an effective isocyanate content of 7.73%.

Examples 11 to 14, Comparative Examples 2 to 5 Polyisocyanate-isocyanurate solution obtained in Examples 1 to 3 and acrylic polyol resin solution Olester Q
182 (manufactured by Mitsui Toatsu Chemicals, Inc., number average molecular weight: 9,500, solid content: 50% by weight, hydroxyl value: 45 mgKOH / g). Preparation of Base Enamel A base enamel of acrylic resin Olester Q182 was blended and prepared as follows. Acrylic resin Orester Q182 50 parts Pigment: Titanium oxide R930 (manufactured by Ishihara Sangyo Co., Ltd.) 50 parts The above mixture was added, and the pigment was kneaded with a three-roll mill to prepare a base enamel. Coating film test Polyisocyanato-isocyanurate solutions obtained in Examples 1 to 3 and acrylic polyol resin Olester Q18
The base enamel prepared in 2 and 3 was blended so that the isocyanate group and the hydroxyl group were equivalent and the pigment content (PWC) was 40% by weight.
A mixed solvent of toluene / butyl acetate / xylene / cellosolve acetate (weight ratio = 30/30/20/15/5) was added, and the mixture was adjusted to 15 seconds / 25 ° C. with a Ford cup # 4 to prepare the non-yellowing urethane of the present invention. A paint resin was obtained. This was applied to a steel plate and a glass plate with an air spray gun (IWATAW-77 type, nozzle diameter 2 mmφ) to a dry film thickness of 25 µ (micron), and allowed to stand at room temperature (20 ° C / 60% RH) for 7 days. After placing
Tested. Also, for comparison, Example 9 and Comparative Example 1
The polyisocyanate-isocyanurate solution obtained in the above and three kinds of aliphatic polyisocyanates as conventional products, namely, (1) Olester NP1000 (manufactured by Mitsui Toatsu Chemicals, Inc.
Buret of hexamethylene diisocyanate),
(2) Coronate EH (produced by Nippon Polyurethane Co., Ltd., isocyanurate of hexamethylene diisocyanate),
(3) IPDI T1890 (manufactured by Daicel Huels Co., Ltd.
The same test was conducted for isophorone diisocyanate (isocyanurate form). Table 1 shows the performance and coating film properties.
~ Shown in Table 2. The coating film test was performed at 20 ° C./60% RH, and the evaluation method was in accordance with JIS k-5400.

The test methods of the items (1) to (9) shown in the table are as follows. (1) Adhesion, according to JIS D-0202. (2) Erichsen extrusion, in accordance with JIS Z-2247. (3) Magic contamination, compliant with JAS 1373. The test piece is placed horizontally, and a line having a quick-drying ink width of 10 mm specified in JIS-6037 (1964) is drawn on the surface of the test piece. After leaving for 24 hours, the cloth is wiped off with a cloth soaked with ethyl alcohol. As a result,
Displays the following. ：: No abnormality, Δ: Slight traces left, ×: Clear traces left. (4) Xylene rubbing (50 times), a test piece was placed on a dyeing fastness tester, and reciprocated 50 times with a load of 500 g with a cotton cloth impregnated with 2 ml of xylene. The following display is performed according to the result. ：: No abnormality, Δ: Slight traces left, ×: Clear traces left. (5) Acid and alkali resistance, compliant with JAS 1373. Place the test piece horizontally, drop 10% sulfuric acid aqueous solution (10% sodium hydroxide solution) on the surface of the test piece, cover with a watch glass for 24 hours, and leave at room temperature for 24 hours. The following display is performed according to the result. ：: No abnormality, Δ: Slight traces left, ×: Clear traces left. (6) WOM yellowing degree, based on JIS k-7103. (7) Gloss (60 ° gloss), conforming to JIS k-5400. (8) Dupont impact (1 / 2in / 500g), JIS k-5400 compliant. (9) Secondary physical properties: After immersion in boiling water for 4 hours, physical properties are measured.

Examples 15-18, Comparative Examples 6-9 Olester Q, a commercially available polyester polyol resin
173 (manufactured by Mitsui Toatsu Chemicals Co., Ltd., solid content 100%, hydroxyl value 256 mgKOH / g), paint preparation and spray coating were carried out in the same manner as in Example 11; 20
(° C./60% RH) for 7 days and then used for the test.
The results are summarized in Tables 3 to 5. The coating film test and evaluation method are 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, 25 g of n-butyl acrylate, 125 g of styrene, 125 g of acrylic acid
g, 25 g of diethylene glycol and 50 g of tert-butylperoxy-2-ethylhexanoate in 2 hours with stirring while stirring a monomer mixture.
g, and the mixture was continuously refluxed for 5 hours to carry out polymerization. After the completion of the polymerization reaction, a part of n-butyl acetate was distilled off to adjust the solid content to 80%. The acrylic polyol resin solution thus obtained had a viscosity of 6500 cp / 25 ° C., a number average molecular weight of 1300, and a hydroxyl value of 92 mgKOH / g.

Reference Example 3 Preparation of Base Enamel The acrylic resin base enamel prepared in Reference Example 2 was blended and prepared as follows. 45 parts of the acrylic polyol resin produced in Reference Example 2 Pigment: titanium oxide R930 (manufactured by Ishihara Sangyo Co., Ltd.) 45 parts Thinner (xylene / toluene / butyl acetate / methyl isobutyl ketone) 10 parts The pigment was kneaded with a roll to prepare a base enamel.

Example 19, Comparative Example 10 The block urethane solution of polyisocyanato-isocyanurate obtained in Example 10 and the acrylic polyol resin solution shown in Reference Example 2 and the base enamel prepared in Reference Example 3 were effectively used. An isocyanate group and a hydroxyl group are blended so as to have an equivalent weight and a pigment content (PWC) of 40% by weight, and ethyl acetate / toluene / butyl acetate / xylene / cellosolve acetate (weight ratio = 30/30/20) is used as a thinner. / 15 /
Add the mixed solvent of 5) and use Ford Cup # 4 for 15 seconds / 25
℃ to obtain a non-yellowing type urethane coating resin of the present invention. This is an air spray gun (IWATAW-77 type,
Nozzle diameter 2mmφ) 25mm dry film thickness on steel plate and glass plate
The coating was performed so as to be μ (micron), forcibly dried at 150 ° C. for 20 minutes, allowed to stand at room temperature (20 ° C./60% RH) for 7 days, and then subjected to a test. The evaluation method is the same as described above. Further, for comparison with a conventional product, the same test was carried out for Olester NP1060PB (a block urethane of hexamethylene diisocyanate buret, manufactured by Mitsui Toatsu Chemicals, Inc.). Table 2 shows the performance of the composition and the properties of the coating film. As a result, polyurethane coatings are generally excellent in adhesion to various coated objects, balance between hardness and flexibility, crack resistance, water resistance, chemical resistance, gloss, appearance, etc. Polyurethane coatings obtained when used as a paint have these properties, as well as excellent weather resistance, light stability, and heat stability, and have various advantages over commercially available polyurethane paints. It has features. That is, the polyisocyanate-isocyanurate used in the non-yellowing type urethane coating resin of the present invention has higher reactivity and higher heat resistance than polyisocyanate derived from aliphatic isocyanate, for example, hexamethylene diisocyanate. Therefore, the initial curing and drying properties are fast, and yellowing upon baking is greatly improved. Further, it has good compatibility, excellent appearance, and the coating film performance is equal to or higher than that of a commercially available product, so that it is suitable for applications where emphasis is placed on workability such as vehicle coating, appearance and coating film performance.

Example 20 Synthesis of Blocked Isocyanate-1 While nitrogen gas was blown into a reaction vessel, 134 parts of trimethylolpropane and 300 parts of ethyl acetate were charged, and the temperature was raised to 80 ° C. while mixing and stirring. Further, 556 parts of the above BCHI were charged over 1 hour. After the completion of the charging, the mixture was allowed to react at 80 ° C. for 10 hours.
The reaction was performed for 4 hours. The obtained solution was distilled by a Smith distilling machine to obtain a solid blocked isocyanate-1.

Example 21 Synthesis of Blocked Isocyanate-2 While blowing nitrogen gas into a reaction vessel, xylol 167
And 500 parts of BCHI, and the mixture was heated to 115 ° C. while stirring. When the NCO% became 18%, the mixture was cooled to 50 ° C. and 254 parts of methyl ethyl ketoxime was added.
After dropwise addition over a period of time, the mixture was further reacted at 50 ° C. for 1 hour. The obtained solution was distilled by a Smith distilling machine to obtain a solid blocked isocyanate-2.

Example 22 Synthesis of Block Isocyanate-3 While blowing nitrogen gas into a reaction vessel, butyl acetate 500
And 500 parts of BCHI, and the mixture was reacted at 80 ° C. for 4 hours while stirring with 3.8 parts of Catalyst A to obtain an isocyanurate-type polyisocyanate having an NCO% of 6%. The obtained solution was charged with 165 parts of ε-caprolactam, heated to 110 ° C, and heated at 4 ° C.
After reacting for an hour, it was distilled with a Smith distilling machine to synthesize solid blocked isocyanate-3.

Example 23 and Comparative Example 11 Elitel ER6610 (Nihon Ester Co., Ltd.)
Isocyanate synthesized in Examples 20 to 22 using polyester resin, OH value 31 KOH mg / g).
To Example 3. As a comparative example, B1530
(Blocked IPDI, manufactured by Huls) was used. The components were mixed according to the formulations described in Examples and Comparative Examples in Table 6, mixed with a Henschel mixer, and then melt-kneaded with a twin-screw kneader. Further, the obtained paint was finely pulverized and then sieved to prepare a powder paint. Thereafter, electrostatic coating was performed on a zinc phosphate-treated iron plate using an electrostatic coating machine, followed by baking at 160 ° C. and 180 ° C. for 20 minutes. The thickness of the obtained coating film was 70 ± 5 μm. From the results shown in Table 6, the baking temperature of 180 ° C. or more was required even in the conventional curing catalyst combined system, but it was 2,5- and / or 2,6-
It is clear that low temperature baking at 160 ° C can be performed by using a blocked isocyanate synthesized from diisocyanatomethylbicyclo [2,2,1] heptane as a curing agent for powder coatings.

[Table 1]

[Table 2]

[Table 3]

[Table 4]

[Table 5]

[Table 6]

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Sekido Takara 1190 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa Prefecture Inside Mitsui Toatsu Chemicals Co., Ltd. Inside Chemical Co., Ltd. (72) Inventor Kiyoshi Shimi 3-5-2 Kasumigaseki, Chiyoda-ku, Tokyo Inside Mitsui Toatsu Chemical Co., Ltd. (72) Inventor Hiroshi Nomura 2572-36 Ono-cho, Machida-shi, Tokyo (56) Reference Reference JP-A-57-7472 (JP, A) JP-A-61-212570 (JP, A) US Pat. No. 3,595,917 (US, A) US Pat. No. 4,522,762 (US, A) (58) Fields investigated (Int. ⁷ , DB name) C07C 265/14 C07D 251/34 C08G 18/79 C09D 5/46 C09D 175/04 CA (STN) REGISTRY (STN)

Claims (28)

(57) [Claims] 1. A compound of the general formula (1) [Wherein R ₁ , R ₂ and R ₃ are an alkylene group having 2 to 12 carbon atoms or a compound represented by the formula (2) (Where k is 0-2, j and m are 1-5, h is 0-2
Which represents an integer), which may be the same or different, and n represents an integer of 1 to 5]
A polyisocyanato-isocyanurate mixture containing two or more polyisocyanato-isocyanurates represented by the formula: 2. The polyisocyanato-isocyanurate mixture according to claim 1, wherein n = 1 in the general formula (1). 3. The polyisocyanate-isocyanurate mixture according to claim 1, wherein n is 2 to 5 in the general formula (1). 4. In the general formula (1), 30 to 90% by weight of a polyisocyanato-isocyanurate in which n is 1 and 10 to 70% by weight of a polyisocyanate-isocyanurate in which n is 2 to 5 The polyisocyanato-isocyanurate mixture according to claim 1, wherein 5. General formula (3) OCN-R ₄ —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): (Where k is 0-2, j and m are 1-5, h is 0-2
The polyisocyanate-isocyanurate mixture according to claim 1, which is obtained by reacting a polycyclic aliphatic diisocyanate represented by the following formula: 6. The polyisocyanate-isocyanurate mixture according to claim 5, wherein the linear aliphatic diisocyanate represented by the 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 polyisocyanate according to claim 5, which is
Isocyanurate mixture. 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 polyisocyanate-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 R ₁ , R ₂ and R ₃ is a group represented by the formula (2): (Where k is 0-2, j and m are 1-5, h is 0-2
Which is an integer), and the remainder is a group having 2 to 2 carbon atoms.
A substantially single polyisocyanato-isocyanurate that is 12 alkylene groups. 10. A general formula (3): OCN-R ₄ —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): (Where k is 0 to 2, j and m are 1 to 5, h is 0 to 2)
A mixture having a molar ratio of 1:11 to 11: 1 with a polycyclic aliphatic diisocyanate represented by the following formula: trimerizing a part of diisocyanate groups in the presence of a trimerization catalyst And about 20 to 5 of the isocyanate groups originally present
As soon as 0% is trimerized, a catalyst poison is added to inactivate the catalyst, the trimerization reaction is stopped, and then unreacted diisocyanate is removed. [Wherein R ₁ , R ₂ and R ₃ are an alkylene group having 2 to 12 carbon atoms or a compound represented by the formula (2): (Where k is 0 to 2, j and m are 1 to 5, h is 0 to 2)
Which represents an integer), which may be the same or different, and n represents an integer of 1 to 5]
A method for producing a polyisocyanato-isocyanurate mixture containing two or more polyisocyanato-isocyanurates represented by the formula: 11. The production method according to claim 10, wherein the trimerization catalyst is used in combination with an alkali metal salt of carboxylic acid and a polyalkylene oxide compound or alcohol. 12. The production method according to claim 10, wherein the linear aliphatic diisocyanate represented by the 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. 11. The production method according to claim 10, wherein 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 production method according to claim 10, which is 2,5- or 2,6-diisocyanatomethylbicyclo [2,2,1] heptane or a mixture thereof. 15. A non-yellowing urethane paint comprising a polyisocyanate-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 component. resin. 16. A non-yellowing urethane coating resin comprising the polyisocyanate-isocyanurate mixture according to claim 5 as a curing agent and a compound having at least two active hydrogens as a main component. A non-yellowing urethane coating resin comprising the polyisocyanate-isocyanurate according to claim 9 as a curing agent and a compound having two or more active hydrogens as a main component. 18. The compounding ratio of the polyisocyanato-isocyanurate mixture to the compound having two or more active hydrogens is 0.8 to 1.2 in equivalent ratio (H / NCO group). 16. The non-yellowing type urethane coating resin according to 16 or 17. 19. A coating composition comprising the non-yellowing urethane coating resin according to claim 15, 16 or 17. 20. The polyisocyanate-isocyanurate mixture represented by the general formula (1) according to claim 1 wherein the isocyanate group is blocked by a compound having at least one active hydrogen in one molecule. A resin curing agent for a urethane paint, comprising: 21. A resin for urethane coating, wherein the isocyanate group of the polyisocyanate-isocyanurate mixture according to claim 5 is blocked by a compound having at least one active hydrogen in one molecule. Curing agent. 22. A resin for urethane coating, wherein the isocyanate group of the polyisocyanato-isocyanurate according to claim 9 is blocked by a compound having at least one active hydrogen in one molecule. Agent. 23. A non-yellowing type urethane coating resin composition containing the resin curing agent for urethane coating according to claim 20, 21 or 22. 24. Blocked by 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. 25. A modified 2,5- or 2,6-diisocyanatomethylbicyclo [2,2,1] heptane,
A curing agent for powder coatings, which is blocked by a compound having at least one active hydrogen in one molecule. 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 a polyol. 26. The curing agent for a powder coating 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 trimerization of 2,5- or 2,6-diisocyanatomethylbicyclo [2,2,1] heptane or a mixture thereof. Claim
25. The curing agent for powder coating according to 25. 28. The curing agent for powder coating according to claim 24, 25, 26 or 27 and a polyester polyol, and the composition ratio of the contents is such that the block in the curing agent for powder coating has a baking temperature. A polyester powder coating composition having an equivalent ratio (H / NCO group) of active hydrogen (H) of the polyester polyol to the isocyanate group (NCO group) to be dissociated of 0.8 to 1.3.