JP2014084426A - Dissociation catalyst for block agent containing quaternary ammonium salt and its use - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dissociation catalyst for a blocking agent having high dissociation effects at low temperature, and to provide its use.SOLUTION: A catalyst containing a quaternary ammonium salt represented by the general formula (1), where Xrepresents at least one kind selected from a group consisting of a hydrogen carbonate group, a monoalkyl carbonate group, and carbonate group, a is an integer in a range of 1 to 2, b is an integer in the range of 1 to 2, is used as a dissociation catalyst for a block agent.

Description

  The present invention relates to a catalyst for dissociating a polyisocyanate blocking agent (hereinafter sometimes referred to as “blocking agent dissociation catalyst”), and a thermosetting composition using the same.

  Polyurethane resin coatings have very good wear resistance, chemical resistance and stain resistance. A general polyurethane resin coating is a two-component type composed of a polyol component and a polyisocyanate component, and each is stored separately and mixed for use during coating. However, since the paint once mixed is cured in a short time, there is a problem in terms of workability at the time of painting because the pot life is short. Further, since the polyisocyanate and water easily react, it is impossible to use in a water-based paint such as an electrodeposition paint. As described above, the conventional two-pack type polyurethane resin paint has many limitations in its use.

In order to improve the above-mentioned problems, a method is known that uses a blocked isocyanate that is inactivated by reacting a polyisocyanate with an active hydrogen group-containing compound (blocking agent).
This blocked isocyanate does not react with the polyol at room temperature, but when heated, the blocking agent dissociates to regenerate the isocyanate group, and the crosslinking reaction with the polyol proceeds. For this reason, the pot life is not limited, and it is possible to preliminarily blend both into a coating material to form a single solution or to apply to a water-based coating material.

  As compounds used as a polyisocyanate blocking agent, for example, ε-caprolactam, methyl ethyl ketone oxime, phenol and the like are known. However, blocked isocyanates using these require a high baking temperature of 140 ° C. or higher to dissociate the blocking agent, which is disadvantageous in terms of energy and cannot be applied to plastic substrates with low heat resistance. there were.

  For this reason, attempts have been conventionally made to lower the baking temperature by using a catalyst (blocking agent dissociation catalyst). As such a catalyst, organic tin such as dibutyltin dilaurate is known (for example, see Non-Patent Document 1), but its use is not preferred because of toxicity problems. Moreover, although a specific quaternary ammonium carboxylate has been reported as a catalyst (see, for example, Patent Document 1), the dissociation temperature is not sufficiently lowered, and a blocking agent dissociation catalyst having a high dissociation effect at low temperatures is desired. Has been.

Japanese Patent No. 2732239

Progress in Organic Coatings 36, 148-172 (1999)

  The present invention has been made in view of the above-described background art, and an object thereof is to provide a blocking agent dissociation catalyst having a high dissociation effect at a low temperature and its use.

  As a result of intensive studies to solve the above problems, the present inventors have found that a catalyst containing a specific quaternary ammonium salt having an n-octyl group is a dissociation catalyst for a blocking agent having a high dissociation effect at low temperatures. In addition, the present inventors have found that the solubility of the catalyst in the thermosetting composition is increased and the catalytic effect is improved, and the present invention has been completed.

  That is, this invention is the block agent dissociation catalyst containing a quaternary ammonium salt as shown below, and a thermosetting composition using the same.

  [1] The following general formula (1)

［式中、Ｘ^ｂ−は炭酸水素基、モノアルキル炭酸基、及び炭酸基からなる群より選ばれる少なくとも１種を表し、ａは１〜２の範囲の整数、ｂは１〜２の範囲の整数である。］
で示される４級アンモニウム塩を含有するブロック剤解離触媒。

[ ^Wherein , X ^b- represents at least one selected from the group consisting of a hydrogen carbonate group, a monoalkyl carbonate group, and a carbonate group, a is an integer in the range of 1 to 2, and b is in the range of 1 to 2. It is an integer. ]
The blocking agent dissociation catalyst containing the quaternary ammonium salt shown by these.

  [2] At least one quaternary ammonium salt selected from the group consisting of trimethylmono n-octylammonium hydrogen carbonate, trimethylmono n-octylammonium monomethyl carbonate, and trimethylmono n-octylammonium carbonate The blocking agent dissociation catalyst according to [1] above, which is an ammonium salt.

  [3] A thermosetting composition comprising the blocking agent dissociation catalyst according to the above [1] or [2], a blocked isocyanate, and a compound having an isocyanate reactive group.

  [4] The thermosetting composition as described in [3] above, wherein the compound having an isocyanate-reactive group is a polyol.

  Since the blocking agent dissociation catalyst of the present invention exhibits a blocking agent dissociation catalytic activity that exceeds that of known catalysts such as organotin, it is extremely useful industrially.

  Moreover, since the thermosetting composition of the present invention uses a blocking agent dissociation catalyst having a high dissociation effect at a low temperature, it is advantageous in terms of energy and can be applied to a substrate having low heat resistance.

  Hereinafter, the present invention will be described in more detail.

  The blocking agent dissociation catalyst of the present invention is characterized by containing a quaternary ammonium salt represented by the general formula (1). Since the quaternary ammonium salt represented by the general formula (1) has an n-octyl group, the solubility of the catalyst in the thermosetting composition is increased, and the effect of the catalyst is improved.

In the general formula (1), X ^b- represents at least one selected from the group consisting of a hydrogen carbonate group, a monoalkyl carbonate group, and a carbonate group, and is not particularly limited. Examples include a monoalkyl carbonate group having an alkyl group having 1 to 8 carbon atoms. Of these, monomethyl carbonate, monoethyl carbonate, monopropyl carbonate, and monobutyl carbonate are particularly preferable.

  In the present invention, the preparation method of the quaternary ammonium salt is not particularly limited. For example, the preparation method (1) in which a quaternary ammonium hydroxide is reacted with carbon dioxide, a tertiary amine and a carbonic acid diester are used. The quaternary ammonium monoalkyl carbonate obtained by the reaction can be prepared by a preparation method (2) in which carbon dioxide or water is reacted.

  Although it does not specifically limit as reaction conditions of the said preparation method (1), It is preferable to carry out at normal temperature or under heating in solvents, such as water and ethanol.

  The quaternary ammonium hydroxide used in the preparation method (1) is trimethylmono n-octylammonium hydroxide represented by the following formula (2).

上記調製法（２）の反応条件としては特に限定するものではないが、３級アミンと炭酸ジエステルの反応は、メタノール、エタノール等の溶媒中又は溶媒の非存在下で、常温又は加熱下で行うことが好ましい。また、４級アンモニウムモノアルキル炭酸塩と、二酸化炭素又は水との反応は、メタノール、エタノール等の溶媒中又は溶媒の非存在下で、常温又は加熱下、必要に応じて適宜発生する炭酸ガスを反応系から除去しながら行うことが好ましい。

Although the reaction conditions for the above preparation method (2) are not particularly limited, the reaction between the tertiary amine and the carbonic acid diester is carried out in a solvent such as methanol or ethanol or in the absence of a solvent at room temperature or under heating. It is preferable. In addition, the reaction between the quaternary ammonium monoalkyl carbonate and carbon dioxide or water is carried out by using carbon dioxide gas appropriately generated as needed at room temperature or under heating in a solvent such as methanol or ethanol or in the absence of a solvent. It is preferable to carry out while removing from the reaction system.

  Examples of the tertiary amine used in the preparation method (2) include dimethylmono n-octylamine.

  Examples of the carbonic acid diester used in the preparation method (2) include dimethyl carbonate.

  The blocking agent dissociation catalyst of the present invention contains a quaternary ammonium salt represented by the general formula (1), and among these, trimethylmono n-octylammonium hydrogen carbonate, trimethylmono n-octylammonium. It is preferable to contain at least one quaternary ammonium salt selected from the group consisting of monomethyl carbonate and trimethylmono n-octylammonium carbonate.

  The blocking agent dissociation catalyst of the present invention can contain a solvent, if necessary. Examples of the solvent include water, ethylene glycol, propylene glycol, 1,4-butanediol, toluene, benzene, methyl ethyl ketone, acetone, ethyl acetate, propylene glycol monomethyl ether acetate, diethylene glycol dimethyl ether, N-methylpyrrolidone, and the like. These solvents may be used alone or in combination of two or more. When the thermosetting composition of the present invention is aqueous, a hydrophilic solvent is preferably used, and when the thermosetting composition of the present invention is non-aqueous, an oleophilic solvent is preferably used.

  Next, the thermosetting composition of the present invention will be described.

  The thermosetting composition of the present invention contains the above-described blocking agent dissociation catalyst of the present invention, a blocked isocyanate, and a compound having an isocyanate-reactive group.

  In the thermosetting composition of the present invention, examples of the block isocyanate include non-aqueous blocked isocyanate and aqueous blocked isocyanate.

  Examples of the non-aqueous blocked isocyanate include known blocking agents (for example, alcohols such as methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, tert-butanol, phenol, cresol, nitrophenol, chloro). Phenols such as phenol and resorcinol, thiols such as benzenethiol, caprolactams such as ε-caprolactam, carbamates such as ethyl carbamate, ketoenols such as acetylacetone, ketoximes such as methyl ethyl ketone oxime, diisopropylamine, triazole, 3, 5-methylpyrazole and other amines, sodium bisulfite, etc.) are used to list known isocyanate compounds or compounds that block their prepolymers. Rukoto can.

  Here, as a well-known isocyanate compound, aliphatic polyisocyanate, alicyclic polyisocyanate, aromatic polyisocyanate, araliphatic polyisocyanate etc. are mentioned, for example.

  Examples of the aliphatic polyisocyanate include 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, And dimer acid diisocyanate.

  Examples of the alicyclic polyisocyanate include 1,3-bis (isocyanatomethyl) cyclohexane, 1,4-bis (isocyanatomethyl) cyclohexane, 3-isocyanatomethyl-3,3,5-trimethylcyclohexane (IPDI). , Isophorone diisocyanate), bis- (4-isocyanatocyclohexyl) methane (hydrogenated MDI), norbornane diisocyanate and the like.

  Examples of aromatic polyisocyanates include 2,4′-diphenylmethane diisocyanate, 4,4′-diphenylmethane diisocyanate, crude MDI, 1,4-phenylene diisocyanate, 2,4-tolylene diisocyanate, and 2,6-tolylene diisocyanate. 3,3′-dimethyl-4,4′-diisocyanatobiphenyl, 3,3′-dimethyl-4,4′-diisocyanatodiphenylmethane, 1,5-naphthylene diisocyanate and the like.

  Examples of the araliphatic polyisocyanate include 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, α, α, α ′, α′-tetramethylxylylene diisocyanate, and the like.

  Moreover, as isocyanate compounds other than the above, for example, isocyanate group-terminated compounds by reaction of isocyanate compounds with active hydrogen group-containing compounds, reaction products of these compounds (for example, adduct-type polyisocyanates, allophanatization reactions, carbodiimidization reactions, Uretodione reaction, isocyanurate reaction, ureton iminate reaction, isocyanate-modified product by biuret reaction, etc.), or a mixture thereof.

  On the other hand, the aqueous blocked isocyanate can be obtained, for example, by reacting a polyisocyanate with a hydrophilic group having at least one active hydrogen group capable of reacting with an isocyanate group and blocking it with a known blocking agent. . Examples of the hydrophilic group include ionic groups such as cations and anions, and nonionic groups. Examples of the nonionic compound for introducing a nonionic group into the polyisocyanate include polyalkylene ether alcohols and polyoxyalkylene fatty acid esters.

  In the thermosetting composition of the present invention, examples of the compound having an isocyanate-reactive group include a polyol. In the present invention, the polyol refers to a compound containing two or more hydroxyl groups having reactivity with an isocyanate group, and specific examples include non-aqueous polyols and aqueous polyols.

  Examples of the non-aqueous polyol include acrylic polyol, polyester polyol, polyether polyol, and epoxy polyol.

  Examples of the acrylic polyol include a copolymer of a polymerizable monomer having one or more active hydrogens in one molecule and a monomer copolymerizable therewith.

  Examples of the polymerizable monomer having one or more active hydrogens in one molecule include acrylic acid hydroxy esters such as 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, and 2-hydroxybutyl acrylate. , Methacrylic acid hydroxyesters such as methacrylic acid-2-hydroxyethyl, methacrylic acid-2-hydroxypropyl, methacrylic acid-2-hydroxybutyl, glycerin acrylic acid monoester or methacrylic acid monoester, trimethylolpropane acrylic acid Monoester or methacrylic acid monoester, or a monomer obtained by ring-opening polymerization of ε-caprolactone with these active hydrogens.

  Examples of monomers copolymerizable with the polymerizable monomer include, for example, acrylic esters such as methyl acrylate, ethyl acrylate, isopropyl acrylate, -n-butyl acrylate, and 2-ethylhexyl acrylate, and methyl methacrylate. , Methacrylates such as ethyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-hexyl methacrylate, cyclohexyl methacrylate, lauryl methacrylate, glycidyl methacrylate, acrylic acid, methacrylic acid , Unsaturated carboxylic acids such as maleic acid and itaconic acid, unsaturated amides such as acrylamide, N-methylol acrylamide and diacetone acrylamide, styrene, vinyl toluene, vinyl acetate, acrylonitrile, etc. It is.

  Examples of polyester polyols include condensed polyester polyols, polycarbonate polyols, and polylactone polyols.

  Examples of the condensed polyester polyol include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6- Dioxanes such as hexanediol, neopentyl glycol, butylethylpropane diol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, dipropylene glycol, tripropylene glycol, and succinic acid, adipic acid, azelaic acid, sebacic acid, Dodecanedicarboxylic acid, maleic anhydride, fumaric acid, 1,3-cyclopentanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid, phthalic acid, naphthalenedicarbo Reaction products of dicarboxylic acids such as acid.

  Specifically, polyethylene adipate diol, polybutylene adipate diol, polyhexamethylene adipate diol, polyneopentylene adipate diol, polyethylene propylene adipate diol, polyethylene butylene adipate diol, polybutylene hexamethylene adipate diol, poly (polytetramethylene ether) ) Adipate-type condensed polyester diols such as adipate diol, and azelate-type condensed polyester diols such as polyethylene azelate diol and polybutylene azelate diol.

  Examples of the polycarbonate polyol include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, and 1,6-hexane. Examples include diols, neopentyl glycol, butyl ethyl propane diol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, dipropylene glycol, tripropylene glycol and other diols and dimethyl carbonate and other dialkyl carbonates. It is done. Specifically, polytetramethylene carbonate diol, poly 3-methylpentamethylene carbonate diol, polyhexamethylene carbonate diol and the like are exemplified.

  Examples of polylactone polyols include ring-opening polymers of ε-caprolactone, γ-butyrolactone, γ-valerolactone, and mixtures of two or more thereof. Specific examples include polycaprolactone diol.

  Examples of the polyether polyol include ethylene glycol, propylene glycol, 1,3-butylene glycol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, neopentyl glycol, catechol, hydroquinone, bisphenol A, and the like. Examples include a reaction product obtained by addition polymerization of monomers such as ethylene oxide, propylene oxide, butylene oxide, styrene oxide, epichlorohydrin, tetrahydrofuran, and cyclohexylene, using a compound containing two or more hydrogen atoms as an initiator. In the case of a reaction product obtained by addition polymerization of two or more monomers, block addition, random addition, or a mixed system of both may be used. Specific examples include polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol and the like.

  Examples of the epoxy polyol include novolak type, β-methyl epichloro type, cyclic oxirane type, glycidyl ether type, glycol ether type, aliphatic unsaturated compound epoxy type, epoxidized fatty acid ester type, polyvalent carboxylic acid ester type, amino acid Examples include glycidyl type, halogenated type, and resorcin type epoxy polyols.

  Moreover, as non-aqueous polyols other than those described above, for example, OH-terminated prepolymers produced by reacting these polyols with isocyanate compounds can also be used.

  On the other hand, examples of the aqueous polyol include compounds obtained by emulsifying, dispersing, or dissolving the above-described non-aqueous polyol in water. Examples of the method of emulsifying, dispersing or dissolving in water include a method of neutralizing by introducing a carboxyl group, a sulfone group or the like. Examples of neutralizers include ammonia and water-soluble amino compounds such as monoethanolamine, ethylamine, dimethylamine, diethylamine, triethylamine, propylamine, dipropylamine, isopropylamine, diisopropylamine, triethanolamine, and butylamine. , Dibutylamine, 2-ethylhexylamine, methylethanolamine, dimethylethanolamine, diethylethanolamine, morpholine and the like. Among these, tertiary amines such as triethylamine and dimethylethanolamine are preferably used.

  In the thermosetting composition of the present invention, the hydroxyl value of the polyol is not particularly limited, but is preferably in the range of 10 to 300 mgKOH / g, more preferably in the range of 20 to 250 mgKOH / g per solid content. . By setting the hydroxyl value to 10 mgKOH / g or more, the strength of the obtained resin is improved, and by setting it to 300 mgKOH / g or less, the plasticity of the obtained resin is improved.

  In the thermosetting composition of the present invention, the polyol component is a composition containing a polyol (a compound containing two or more hydroxyl groups having reactivity with an isocyanate group), a neutralizing agent, an antioxidant, and water. Usually used, the solid content means a polyol, a neutralizing agent, and an antioxidant.

  The hydroxyl value of the polyol can be measured by the method defined in JIS-K0070. That is, it can be measured by adding and dissolving acetic anhydride and pyridine to a sample, allowing to cool, and then neutralizing titrating a sample solution prepared by adding water and toluene with an ethanol solution of potassium hydroxide. The hydroxyl value is represented by the number of mg of potassium hydroxide required to neutralize acetic acid consumed to acetylate the hydroxyl group contained in a 1 g sample.

  The equivalent ratio ([hydroxyl group] / [isocyanate group]) of the hydroxyl group and isocyanate group of the polyol in the thermosetting composition of the present invention is determined by the required coating film properties and is not particularly limited. It is in the range of 0.2-2.

  The amount of the blocking agent dissociation catalyst of the present invention used in the thermosetting composition of the present invention is the above-mentioned amount of the quaternary ammonium salt used relative to the amount of blocked isocyanate used ([the amount of quaternary ammonium salt used) / [block isocyanate]. The amount used is generally 0.1 to 15% by weight, preferably 0.5 to 10% by weight, more preferably 1 to 5% by weight. Sufficient low-temperature curability can be obtained by setting the amount of quaternary ammonium salt used to 0.1% by weight or more based on the amount of blocked isocyanate used. On the other hand, even if the amount of quaternary ammonium salt used exceeds 15% by weight based on the amount of blocked isocyanate, no further improvement in low-temperature curability is observed, which is economically disadvantageous.

  The amount of the blocking agent dissociation catalyst of the present invention used in the thermosetting composition of the present invention is the amount of the quaternary ammonium salt used relative to the solid content ([the amount of quaternary ammonium salt used] / [solid content]. ) Is usually 0.05 to 10% by weight, preferably 0.25 to 5% by weight, more preferably 0.5 to 3% by weight. In the present invention, the “solid content” represents a component other than the solvent in the thermosetting composition. For example, in the case of a non-aqueous thermosetting composition, other than the solvent such as butyl acetate and methyl ethyl ketone in the non-aqueous polyol. And the components other than the solvent such as methyl ethyl ketone in the non-aqueous blocked isocyanate, and in the case of the aqueous thermosetting composition, the components other than the solvent such as water in the aqueous polyol and the aqueous blocked isocyanate The total with components other than solvents, such as water, is represented. Sufficient low-temperature curability can be obtained by setting the amount of quaternary ammonium salt used to 0.05% by weight or more based on the solid content. On the other hand, even if the amount of quaternary ammonium salt used exceeds 10% by weight with respect to the solid content, no further improvement in low-temperature curability is observed, which is economically disadvantageous.

  In the thermosetting composition of the present invention, additives, pigments, solvents and the like commonly used in the technical field can be used as necessary.

  Additives are not particularly limited, for example, hindered amine-based, benzotriazole-based, benzophenone-based ultraviolet absorbers, perchlorate-based, hydroxylamine-based coloring inhibitors, hindered phenol-based, Examples thereof include phosphorus-based, sulfur-based and hydrazide-based antioxidants, tin-based, zinc-based and amine-based urethanization catalysts, leveling agents, rheology control agents, pigment dispersants and the like.

  Examples of the pigment include, but are not limited to, organic pigments such as quinacridone, azo, and phthalocyanine, inorganic pigments such as titanium oxide, barium sulfate, calcium carbonate, and silica, other carbon pigments, and metal foils. And pigments such as pigments and rust preventive pigments.

  Examples of the solvent include, but are not limited to, hydrocarbons such as benzene, toluene, xylene, cyclohexane, mineral spirit, naphtha, ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone, ethyl acetate, and acetic acid-n. -Esters, such as butyl and cellosolve acetate, are mentioned, These solvents may be used independently and may use 2 or more types together.

  The thermosetting composition of the present invention is a precoat metal / rust preventive for metal products such as top and middle coatings for automobiles, chipping-resistant coatings, electrodeposition coatings, automotive parts coatings, automotive repair coatings, home appliances and office equipment. It can be used as a steel sheet, a paint for building materials, a paint for plastics, an adhesive, an adhesiveness imparting agent, a sealing agent and the like.

  The following examples further illustrate the present invention, but the present invention is not limited to these examples.

  In the following examples, baking of the thermosetting composition and measurement of solvent resistance were carried out as shown below.

<Baking of thermosetting composition>
The thermosetting composition was applied to an aluminum plate (A1050 made by Partec Co., Ltd.), preliminarily dried in an oven at 50 ° C. for 30 minutes, and then baked in an oven at a predetermined temperature for 30 minutes.

<Measurement of solvent resistance>
The above-mentioned baked coating film was cooled to room temperature, then rubbed with absorbent cotton soaked with methyl ethyl ketone, and the number of round trips until the coating film surface was scratched was measured to evaluate the solvent resistance.

Production Example 1 (Preparation of non-aqueous blocked isocyanate)
A stirring blade was attached to a four-necked flask equipped with a nitrogen blowing tube, and the inside of the vessel was made into a nitrogen atmosphere. Then, Coronate HX (manufactured by Nippon Polyurethane Co., Ltd., hexamethylene diisocyanate trimer, NCO 21.3 wt% ) 50.2 g and dehydrated methyl ethyl ketone 114 g were charged and stirred at 40 ° C. for 5 minutes. Thereafter, a dropping funnel was attached to the container, and 22.2 g of methyl ethyl ketone oxime was dropped into the container over 1 hour while maintaining the temperature at 40 ° C. Then, a reflux condenser was attached to the container and reacted at 70 ° C. for 1 hour. When isocyanate was no longer detected, the reaction was stopped by cooling to room temperature to obtain a non-aqueous blocked isocyanate. The obtained non-aqueous blocked isocyanate had a solid concentration of 40.0% by weight and an effective NCO of 1.36 mmol / g.

  Here, the effective NCO means the amount of isocyanate groups (NCO) that can be reacted by heating the blocked isocyanate to dissociate the blocking agent. An effective NCO of 1.36 mmol / g means that 1.36 mmol of isocyanate groups are potentially contained in 1 g of blocked isocyanate (regenerated by dissociation of the blocking agent).

Production Example 2 (Preparation of aqueous blocked isocyanate)
A stirring blade and a reflux condenser were attached to a four-necked flask equipped with a nitrogen blowing tube, and the inside of the vessel was made a nitrogen atmosphere. Next, Coronate HX (manufactured by Nippon Polyurethane, Hexamethylene diisocyanate trimer, NCO 21.3% by weight) 49.0 g, polyethylene glycol monomethyl ether (Aldrich, average molecular weight 550) 13.7 g were charged in the container, The reaction was carried out at 80 ° C. for 9 hours. Thereafter, 18.6 g of methyl ethyl ketone oxime and 20.0 g of methyl ethyl ketone were added to the container and reacted at 80 ° C. for 3 hours. When no isocyanate was detected, the reaction was stopped by cooling to room temperature.

  To 100 g of the resulting composition, 150 g of water was gradually added with stirring, and emulsified and dispersed in water. Residual methyl ethyl ketone was removed from the obtained emulsified dispersion with an evaporator. The obtained aqueous blocked isocyanate was a stable dispersion having a solid content concentration of 39.0% by weight and an effective NCO of 1.19 mmol / g.

Production Example 3 (Preparation of quaternary ammonium salt)
A 200 ml autoclave was charged with 15.4 g of dimethylmono-n-octylamine, 13.2 g of dimethyl carbonate and 31.4 g of methanol, and stirred at 110 ° C. for 12 hours for reaction. This was recovered in a one-necked eggplant flask (recovered amount 57.9 g), 35.1 g of ethylene glycol was added, and then the interior of the container was reduced to 30 ° C. to remove unreacted dimethyl carbonate and methanol, and trimethylmono-n- 58.5 g of a 40.0 wt% ethylene glycol solution of octylammonium monomethyl carbonate was obtained.

Production Example 4 (Preparation of quaternary ammonium salt)
30.0 g of a 40.0 wt% ethylene glycol solution of trimethylmono n-octylammonium monomethyl carbonate obtained in Production Example 3 was charged into a Griffin beaker and stirred at 25 ° C. while bubbling carbon dioxide using a carbon dioxide cylinder. And reacted. The reaction was carried out for 5 hours to obtain 29.3 g of a 38.6 wt% ethylene glycol solution of trimethylmono n-octylammonium hydrogen carbonate.

Production Example 5 (Preparation of quaternary ammonium salt)
A 200 ml autoclave was charged with 15.5 g of dimethylmono-n-octylamine and 44.5 g of dimethyl carbonate, and stirred at 110 ° C. for 12 hours for reaction. This was recovered in a one-necked eggplant flask (recovered amount 58.1 g), 29.0 g of ethylene glycol was added, and then the inside of the container was reduced to 30 ° C. under reduced pressure to remove unreacted dimethyl carbonate, and trimethylmono n-octylammonium. 48.4 g of a 40.0 wt% ethylene glycol solution of carbonate was obtained.

Example 1 (Evaluation of catalytic activity of quaternary ammonium salt in non-aqueous thermosetting composition)
Non-aqueous acrylic polyol (produced by DIC, Acrydic A-801, solid content concentration 50.2 wt%, hydroxyl value 102 mg KOH / g based on solid content) with composition shown in Table 1, non-aqueous obtained in Production Example 1 After mixing the blocked isocyanate, a 40.0 wt% ethylene glycol solution of trimethylmono n-octylammonium monomethyl carbonate obtained in Production Example 3 was added with stirring to contain trimethylmono n-octylammonium monomethyl carbonate. A non-aqueous thermosetting composition was obtained.

  The obtained non-aqueous thermosetting composition was baked at 80 ° C., 90 ° C., 100 ° C., 110 ° C., and 120 ° C., and then the solvent resistance was measured.

Examples 2-3.
With the composition shown in Table 1, a non-aqueous thermosetting composition containing a quaternary ammonium salt was obtained in the same manner as in Example 1.

  The obtained non-aqueous thermosetting composition was baked at 80 ° C., 90 ° C., 100 ° C., 110 ° C., and 120 ° C., and then the solvent resistance was measured.

  The above results are also shown in Table 1.

比較例１ （非水性熱硬化性組成物における触媒無添加の硬化性評価）
表２に示す組成で、非水性アクリルポリオール（ＤＩＣ社製、アクリディックＡ−８０１、固形分濃度５０．２重量％、固形分に対する水酸基価１０２ｍｇＫＯＨ／ｇ）、製造例１で得られた非水性ブロックイソシアネートを混合し、触媒を含有しない非水性熱硬化性組成物を得た。

Comparative Example 1 (Curability evaluation without addition of catalyst in non-aqueous thermosetting composition)
Non-aqueous acrylic polyol (made by DIC, ACRICID A-801, solid content concentration of 50.2 wt%, hydroxyl value of 102 mg KOH / g based on solid content) with composition shown in Table 2, non-aqueous obtained in Production Example 1 Block isocyanate was mixed to obtain a non-aqueous thermosetting composition containing no catalyst.

得られた非水性熱硬化性組成物を８０℃、９０℃、１００℃、１１０℃、１２０℃で焼付けた後、耐溶剤性の測定を行った結果を表２に示す。

The obtained non-aqueous thermosetting composition was baked at 80 ° C., 90 ° C., 100 ° C., 110 ° C., and 120 ° C., and the solvent resistance measurement results are shown in Table 2.

  As is clear from Tables 1 and 2, in Comparative Example 1, the number of rubbing was less than 5 at 120 ° C. and the coating was not cured, whereas in Examples 1 to 3, the number of rubbing was 100 at 90 ° C. Since the coating film was cured, it was found that the dissociation temperature of the blocking agent was lowered by the addition of the quaternary ammonium salt.

Comparative Example 2 (Curability Evaluation of Known Catalyst in Nonaqueous Thermosetting Composition)
Non-aqueous acrylic polyol (made by DIC, ACRICID A-801, solid content concentration of 50.2 wt%, hydroxyl value of 102 mg KOH / g based on solid content) with composition shown in Table 2, non-aqueous obtained in Production Example 1 After mixing the blocked isocyanate, an 8 wt% propylene glycol monomethyl ether acetate solution of dibutyltin dilaurate was added with stirring to obtain a non-aqueous thermosetting composition containing a known catalyst.

  The obtained non-aqueous thermosetting composition was baked at 80 ° C., 90 ° C., 100 ° C., 110 ° C., and 120 ° C., and the results of solvent resistance measurement are also shown in Table 2.

  As is clear from Tables 1 and 2, in Comparative Example 2, the number of rubbing did not reach 100 times at 120 ° C., whereas in Examples 1 to 3, the number of rubbing reached 100 times at 90 ° C. It can be seen that the quaternary ammonium salt has a blocking agent low-temperature dissociation activity superior to that of dibutyltin dilaurate.

Comparative Example 3
With the composition shown in Table 2, a non-aqueous thermosetting composition containing triethylmonomethylammonium octylate (manufactured by Sun Apro, U-CAT18X) described in Patent Document 1 was obtained in the same manner as in Comparative Example 2.

  The obtained non-aqueous thermosetting composition was baked at 80 ° C., 90 ° C., 100 ° C., 110 ° C., and 120 ° C., and the results of solvent resistance measurement are also shown in Table 2.

  As is clear from Tables 1 and 2, in Comparative Example 3, the number of rubbing reaches 100 times at 120 ° C., whereas in Examples 1 to 3, the number of rubbing reaches 100 times at 90 ° C. It can be seen that the quaternary ammonium salt has a blocking agent low-temperature dissociation activity superior to that of triethylmonomethylammonium octylate.

Example 4 (Evaluation of catalytic activity of quaternary ammonium salt in aqueous thermosetting composition)
An aqueous acrylic polyol (manufactured by Asia, WAP-768, solid content concentration 40.0% by weight, hydroxyl value 57.5 mgKOH / g based on solid content) having the composition shown in Table 3 and the aqueous block obtained in Production Example 2. After mixing the isocyanate, a 40.0% by weight ethylene glycol solution of trimethylmono n-octylammonium monomethyl carbonate obtained in Production Example 3 was added with stirring to contain trimethylmono n-octylammonium monomethyl carbonate. An aqueous thermosetting composition was obtained.

  Table 3 shows the results of measuring the solvent resistance after baking the obtained aqueous thermosetting composition at 110 ° C, 120 ° C, 130 ° C and 140 ° C.

実施例５〜６．
表３に示す組成で、実施例４と同様の方法により、４級アンモニウム塩を含有する水性熱硬化性組成物を得た。

Examples 5-6.
With the composition shown in Table 3, an aqueous thermosetting composition containing a quaternary ammonium salt was obtained in the same manner as in Example 4.

  The obtained aqueous thermosetting composition was baked at 110 ° C., 120 ° C., 130 ° C., and 140 ° C., and the results of the solvent resistance measurement are also shown in Table 3.

Comparative Example 4 (Curability evaluation without addition of catalyst in aqueous thermosetting composition)
An aqueous acrylic polyol (manufactured by Asia, WAP-768, solid content concentration 40.0% by weight, hydroxyl value 57.5 mgKOH / g based on solid content) having the composition shown in Table 3 and the aqueous block obtained in Production Example 2. Isocyanate was mixed to obtain an aqueous thermosetting composition containing no catalyst.

  Table 3 shows the results of measuring the solvent resistance after baking the obtained aqueous thermosetting composition at 110 ° C, 120 ° C, 130 ° C and 140 ° C.

  As is clear from Table 3, the number of rubbing reaches 100 times at 140 ° C. in Comparative Example 4, whereas the number of rubbing reaches 100 times at 120 ° C. in Examples 4 to 6, and therefore, the addition of a quaternary ammonium salt It can be seen that the dissociation temperature of the blocking agent decreased.

  The blocking agent dissociation catalyst of the present invention has the possibility of being used as a catalyst for dissociating the blocking agent of polyisocyanate, and contains the blocking agent dissociation catalyst, blocked isocyanate, and a compound having an isocyanate reactive group. The thermosetting composition is used as a thermosetting resin that is baked and has excellent durability.

Claims (4)

The following general formula (1)

[ ^Wherein , X ^b- represents at least one selected from the group consisting of a hydrogen carbonate group, a monoalkyl carbonate group, and a carbonate group, a is an integer in the range of 1 to 2, and b is in the range of 1 to 2. It is an integer. ]
The blocking agent dissociation catalyst containing the quaternary ammonium salt shown by these. The quaternary ammonium salt is at least one quaternary ammonium salt selected from the group consisting of trimethylmono n-octylammonium hydrogen carbonate, trimethylmono n-octylammonium monomethyl carbonate, and trimethylmono n-octylammonium carbonate. The blocking agent dissociation catalyst according to claim 1. A thermosetting composition comprising the blocking agent dissociation catalyst according to claim 1 or 2, a blocked isocyanate, and a compound having an isocyanate-reactive group. The thermosetting composition according to claim 3, wherein the compound having an isocyanate-reactive group is a polyol.