JPH10168157A - Water-dispersible blocked isocyanate composition, and aqueous coating composition and aqueous adhesive composition using the same - Google Patents

Abstract

(57) [Problem] To improve the performance of a water-dispersible blocked isocyanate so as to meet advanced requirements for the appearance (particularly gloss and sharpness) of a coating film such as a paint or a coating. A blocked isocyanate composition comprising an isocyanate group-terminated precursor and a blocking agent that blocks free isocyanate groups of the precursor. The isocyanate group-terminated precursor contains at least an organic diisocyanate, a low-molecular-weight glycol, and a hydrophilic surfactant having at least one active hydrogen group; and the precursor has an isocyanurate ring structure, 1. The average number of functional groups (f) is 2.
0 ≦ f ≦ 4.2, content of low molecular glycol (X) is 0.5 wt% ≦ X ≦ 15 wt%, content of hydrophilic surfactant (Y) is 0.1 wt% ≦ Y ≦ 50 wt%. is there.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a water-dispersible blocked isocyanate composition, an aqueous coating composition containing an aqueous resin as a main component, and an aqueous adhesive composition.

[0002]

2. Description of the Related Art Heretofore, paints, adhesives and coatings containing an organic solvent having excellent polymer solubility have been widely used. However, the organic solvents contained in these paints and the like may cause harmful effects on human bodies, safety and health problems such as explosion and fire, and pollution problems such as air pollution.

Accordingly, in recent years, in order to solve the above-mentioned problems due to the use of organic solvents, paints and the like for “aqueous” systems that do not substantially use organic solvents have been actively developed.

In aqueous systems, aqueous resins such as aqueous solutions of water-soluble polymers, aqueous dispersions of water-dispersible polymers dispersed in water, aqueous emulsions and aqueous suspensions have been used. An aqueous system (one-component system) using only an aqueous resin often cannot exhibit the physical properties required for the above-mentioned paints and the like, and thus a crosslinking agent is usually used in combination for the purpose of improving weather resistance and adhesion. .

As an example of using such a cross-linking agent, a system (two-component system) in which a curing agent having free isocyanate and the above aqueous resin are combined is known.
However, in this two-part system, the work life (work life) after blending the curing agent and the polymer component is considered.
Or pot life) is short, and there is a problem in workability of paint and the like.

As an example to compensate for the disadvantages of this two-part system,
A method using a water-dispersible blocked isocyanate as the crosslinking agent is known. This is a system in which the blocking agent is dissociated by heating at the time of using a paint or the like, the free isocyanate is regenerated, and the active isocyanate of the polymer component of the aqueous resin is reacted to form the polymer into a network. . In a system using such a water-dispersible blocked isocyanate, since the isocyanate group is blocked, the pot life is not limited unlike the above-described two-component system using free isocyanate.

A specific example of a system using the water-dispersible blocked isocyanate is disclosed in JP-A-61-3142.
No. 2 and JP-A-4-159260. Among them, the blocked isocyanates used for improving the dispersion stability when mixed with a water-soluble polymer solution or an aqueous emulsion are included. For this purpose, hydrophilic surfactants have been introduced.

[0008]

In recent years, the demand for the appearance of a coating film (particularly, gloss and sharpness) of a paint or a coating has been increasing due to the sophistication of the demand for the resulting product such as painting. From the point described above,
Further improvements in the performance of the water-dispersible blocked isocyanates described in JP-A-31422 and JP-A-4-159260 have been demanded.

[0009]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that a resin constituting the main agent (aqueous resin) in an aqueous two-part system is mixed with a water-dispersible blocked isocyanate composition (particularly, the hydrophilicity of the isocyanate). Surfactant)
Has been found to be extremely effective in improving the properties of the coating film appearance (especially in improving gloss and sharpness).

As a result of further research based on such findings, the present inventors have found that not only can a low-molecular-weight glycol and a hydrophilic surfactant be introduced into a water-dispersible blocked isocyanate in a well-balanced manner, but also to the isocyanate. Furthermore, it has been found that introduction of an isocyanurate ring structure not only gives a coating film having excellent gloss and sharpness, but also improves the weather resistance and heat resistance of the coating film.

The water-dispersible blocked isocyanate of the present invention is based on the above findings, and more specifically, a blocked isocyanate composition comprising an isocyanate group-terminated precursor and a blocking agent that blocks free isocyanate groups of the precursor. Wherein the isocyanate group-terminated precursor contains at least an organic diisocyanate, a low molecular weight glycol, and a hydrophilic surfactant having at least one active hydrogen group; and the precursor has an isocyanurate ring structure. And the average number of functional groups (f) is 2.0 ≦ f ≦ 4.
2. The content (X) of the low molecular glycol is 0.5 wt% ≦
X ≦ 15 wt%, and the content (Y) of the hydrophilic surfactant is 0.1 wt% ≦ Y ≦ 50 wt%.

According to the present invention, there is further provided a blocked isocyanate composition comprising an isocyanate group-terminated precursor and a blocking agent for blocking a free isocyanate group of the precursor;
An organic diisocyanate, a low molecular weight glycol, a hydrophilic surfactant having at least one active hydrogen group, and at least a hydrophobic organic compound having at least one active hydrogen group and having 7 or more carbon atoms; and The precursor has an isocyanurate ring structure and the average number of functional groups (f) is 2.0 ≦ f
≦ 4.2, content of low molecular glycol (X) is 0.5w
t% ≦ X ≦ 15 wt%, hydrophilic surfactant content (Y) is 0.1 wt% ≦ Y ≦ 50 wt%, and hydrophobic organic compound content (Z) is 0 wt% <Z ≦ 30 wt%. A water-dispersible blocked isocyanate composition is provided.

According to the present invention, there is further provided a blocked isocyanate composition comprising an isocyanate group-terminated precursor and a blocking agent for blocking a free isocyanate group of the precursor;
At least an organic diisocyanate, a low molecular glycol, and a hydrophilic surfactant having at least one active hydrogen group; and wherein the blocked isocyanate composition is 100% in a solution of an organic solvent having a solid content of 80%. ~ 100,
A water-dispersible blocked isocyanate composition having a viscosity of 000 mPa · s / 25 ° C. is provided.

According to the present invention, there is further provided a blocked isocyanate composition comprising an isocyanate group-terminated precursor and a blocking agent for blocking a free isocyanate group of the precursor;
At least an organic diisocyanate, a low molecular weight glycol, and a hydrophilic surfactant having at least one active hydrogen group; and wherein the blocked isocyanate composition is in the form of an organic solvent solution having a solid content of 80%. 0.0 to 15.0
There is provided a water-dispersible blocked isocyanate composition characterized by having an effective NCO content of wt%.

According to the present invention, there is further provided a blocked isocyanate composition comprising an isocyanate group-terminated precursor and a blocking agent for blocking a free isocyanate group of the precursor;
At least an organic diisocyanate, a low molecular weight glycol, and a hydrophilic surfactant having at least one active hydrogen group; A water-dispersible blocked isocyanate composition having a gloss of 60 to 100 under a condition of 60 ° is provided.

According to the present invention, there is further provided an aqueous coating composition comprising at least one of the above-mentioned “water-dispersible blocked isocyanate composition” and an aqueous resin containing an active hydrogen group; Number of moles of blocked isocyanate groups in the isocyanate composition,
An aqueous coating composition having a ratio of the number of moles of active hydrogen groups in the resin constituting the aqueous resin of 1: 9 to 9: 1 is provided.

According to the present invention, there is further provided an aqueous adhesive composition comprising at least one of the above-mentioned “water-dispersible blocked isocyanate composition” and an aqueous resin containing an active hydrogen group; Aqueous adhesive composition wherein the ratio of the number of moles of blocked isocyanate groups in the reactive blocked isocyanate composition to the number of moles of active hydrogen groups in the resin constituting the aqueous resin is 1: 9 to 9: 1 Things are provided.

According to the knowledge of the present inventors, in the water-dispersible blocked isocyanate composition of the present invention described above,
Since low-molecular glycol and hydrophilic surfactant (and, if necessary, hydrophobic chain having an appropriate chain length) are introduced in a well-balanced manner, the dispersibility of blocked isocyanate molecules in the aqueous resin (base agent) is improved. It is presumed that not only can a uniform mixture be prepared based on the above, but also that the compatibility between the main agent and the blocked isocyanate molecular skeleton is dramatically improved, so that the gloss and sharpness of the coating film are dramatically improved. You.

According to the knowledge of the present inventor, in the blocked isocyanate composition of the present invention, even when the blocking agent of the isocyanate group comes off by heating or the like, the hydrophilic group bonded to another isocyanate group ( In an embodiment in which a hydrophobic chain having an appropriate chain length is also introduced, it is estimated that the hydrophilic group and / or the hydrophobic group) do not substantially deviate from the isocyanate group. Accordingly, it is presumed that the blocked isocyanate of the present invention can maintain a suitable hydrophilic / hydrophobic balance even after deblocking with respect to the aqueous resin constituting the main agent such as a paint.

On the other hand, according to the findings of the present inventors,
The reason that the conventional water-dispersible blocked isocyanate in which only a hydrophilic surfactant is introduced gives a coating film appearance inferior in gloss and sharpness is that the resin constituting the main agent (aqueous resin) and the aqueous dispersion It is presumed to be based on the fact that the compatibility with the reactive blocked isocyanate was low.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described more specifically. In the following description, “parts” and “%” representing quantitative ratios are based on weight unless otherwise specified.

(Water-dispersible blocked isocyanate) The water-dispersible blocked isocyanate of the present invention is a blocked isocyanate comprising an isocyanate group-terminated precursor and a blocking agent for blocking a free isocyanate group of the precursor.

(Isocyanate Group Terminal Precursor) In the present invention, the isocyanate group terminal precursor is an isocyanate containing at least an organic diisocyanate part, a low molecular weight glycol part and a hydrophilic surfactant part having at least one active hydrogen group. It is a base terminal precursor.

(Organic diisocyanate) The organic diisocyanate usable in the present invention includes 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, and 4,4'- Diphenylmethane diisocyanate,
2,4'-diphenylmethane diisocyanate, 2,
2'-diphenylmethane diisocyanate, 4,4'-
Diphenyl ether diisocyanate, 2-nitrodiphenyl-4,4'-diisocyanate, 2,2'-diphenylpropane-4,4'-diisocyanate, 3,
3'-dimethyldiphenylmethane-4,4'-diisocyanate, 4,4'-diphenylpropanediisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, naphthylene-1, 4-diisocyanate, naphthylene-1,5-diisocyanate, 3,
Aromatic isocyanates such as 3'-dimethoxydiphenyl-4,4'-diisocyanate; hexamethylene-1,
6-diisocyanate (hereinafter abbreviated as “HDI”), 1,4-tetramethylene diisocyanate, 2-
Aliphatic isocyanates such as methylpentane-1,5-diisocyanate and lysine diisocyanate; aralkyls such as xylylene-1,4-diisocyanate and xylylene-1,3-diisocyanate Diisocyanate; isophorone diisocyanate (hereinafter referred to as “IPD
I "), hydrogenated tolylene diisocyanate
And alicyclic diisocyanates such as hydrogenated xylene diisocyanate, hydrogenated diphenylmethane diisocyanate, and hydrogenated tetramethyl xylene diisocyanate.

These organic diisocyanates may be used alone or in the form of a mixture of two or more. Furthermore, various modified forms of these organic diisocyanates, for example, adduct modified forms, buret modified forms, carbodiimide modified forms, uretdione modified forms, uretoimine modified forms, and the like may be used as necessary.

Among the above-mentioned organic diisocyanates,
From the viewpoints of water dispersion stability, weather resistance after water dispersion, etc., HDI (hexamethylene diisocyanate) which is a non-yellowing isocyanate or a modified product thereof (particularly, a modified isocyanurate of HDI) can be used more preferably. is there.

The low molecular weight glycol that can be used in the present invention includes:
Effective N suitable for water-dispersible blocked isocyanate composition
In order to have a CO content, its molecular weight is 62-500.
(More preferably 75 to 250). In addition, the effective NCO content in the present invention indicates the NCO content of the polyisocyanate remaining after removing the blocking agent in the blocked isocyanate composition.

Examples of low molecular weight glycols which can be suitably used in the present invention include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, and 1,3-butanediol. Butanediol, 1,4-butanediol, 1,5-pentanediol, 2-methyl-
1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, neopentyl glycol, 2,2-diethyl -1,3-propanediol, 2-n-butyl-2-ethyl-1,3-propanediol, 2,2,4-trimethyl-1,3-pentaneddiol, 2-ethyl-1 , 3-hexanediol,
2-n-hexadecane-1,2-ethylene glycol,
2-n-eicosan-1,2-ethylene glycol, 2
-N-octacosan-1,2-ethylene glycol, hydrogenated bisphenol A, diethylene glycol, dipropylene glycol, 3-hydroxy-2,2-dimethylpropyl-3-hydroxy-2,2-dimethylpropyl Onet and the like. These glycols may be used in combination of two or more as necessary.

Among the above-mentioned low molecular glycols, from the viewpoint of the compatibility of the aqueous resin, a low molecular glycol having a side chain can be particularly preferably used. Examples of the low molecular weight glycol having such a side chain include 1,2-propanediol, 1,2-butanediol, 1,3-butanediol, neopentyl glycol, and 2-n-butyl-.
2-ethyl-1,3-propanediol and the like.

In the present invention, glycerin, trimethylolpropane, pentaerythritol and the like are used.
Although a polyol having a trifunctional or higher functionality of 0 or less can be used, the amount of the polyol used is described in J. Am. P. It is preferable to consider the gelation theory theoretically calculated by Flory, Khun et al., And the reactivity ratio of the reactive groups.

The above-mentioned low molecular weight glycol has a hydrocarbon group in its molecular skeleton, and the introduction of the low molecular weight glycol into the isocyanate molecule allows the isocyanate to react with the molecular skeleton of the resin constituting the aqueous resin. Since the compatibility is improved, gloss and sharpness when the isocyanate molecule is formed into a coating film are improved. In addition, low molecular weight glycols
Since it is functional, it is introduced not at the terminal of the self-emulsifying polyisocyanate molecule but at (close to) the center of the molecular chain, and this also contributes to the improvement of compatibility.

In the present invention, when an isocyanurate ring structure is introduced into a water-dispersible blocked isocyanate, it is preferable to form an isocyanurate-terminated prepolymer obtained by subjecting a low-molecular-weight glycol to a urethanization reaction. In such a case, a catalytic effect of the urethane bond occurs on the isocyanuration reaction, and the entire system reacts uniformly, so that a partially gelled product (polymer) is obtained.
This is because the reaction can smoothly proceed without generating the compound.

(Hydrophilic surfactant) The hydrophilic surfactant used in the present invention is not particularly limited, and one or more known surfactants can be appropriately selected and used. More specifically, for example, as the hydrophilic surfactant, a nonionic hydrophilic surfactant such as poly (oxyalkylene) ether; -COOM, -SO ₃ M (M is an alkali metal, an ammonium group, an organic Anionic hydrophilic surfactants such as amines); and cationic hydrophilic surfactants such as quaternary ammonium.

(Nonionic hydrophilic surfactant) Examples of the nonionic hydrophilic surfactant include poly (oxyalkylene) ethers and polyoxyalkylene fatty acid esters containing one or more active hydrogen groups. No.

Examples of the active hydrogen group-containing compound which can be used as an initiator in the production of the poly (oxyalkylene) ether include, for example, methanol, n-butanol,
Examples include cyclohexanol, phenol, ethylene glycol, propylene glycol, aniline, trimethylolpropane, and glycerin. Above all, from the viewpoint of the dispersion stability of isocyanate, using an alcohol having a smaller molecular weight (preferably having a molecular weight of 80 or less) such as methanol, ethanol, and ethylene glycol,
It is preferable to make the hydrophilicity higher.

On the other hand, examples of the fatty acid that can be used for producing the polyoxyalkylene fatty acid ester include acetic acid, propionic acid, and butyric acid. Among them, from the viewpoint of dispersion stability, it is preferable to use a lower fatty acid (preferably having 4 or less carbon atoms) to further increase the hydrophilicity.

The degree of polymerization of the polyether present in the poly (oxyalkylene) ether, polyoxyalkylene fatty acid ester or the like is preferably 3 to 90, more preferably 5 to 50. As the polyether, a pure ethylene oxide chain and / or a mixed alkylene oxide chain (preferably containing 70 (mol)% or more of ethylene oxide units in all alkylene oxide units)
Any of these can be used.

(Anionic hydrophilic surfactant) The anionic hydrophilic surfactant described above usually comprises an organic acid having at least one active hydrogen group and a neutralizing agent. As the organic acids and the neutralizing agent, either a single compound or a mixture of two or more compounds can be used.

Examples of the organic acids include α-oxypropionic acid, oxysuccinic acid, dioxysuccinic acid, ε
-Oxypropane-1,2,3-tricarboxylic acid, hydroxyacetic acid, α-hydroxybutyric acid, hydroxystearic acid, ricinoleic acid, ricinoelaidic acid, ricinostearolic acid, salicylic acid, mandelic acid and other hydroxy fatty acids; oleic acid , Ricinoleic acid, hydroxy fatty acids obtained by hydroxylating unsaturated fatty acids such as linoleic acid; glutamine, asparagine, lysine, diaminopropionic acid, ornithine, diaminobenzoic acid, diaminobenzenesulfonic acid and other diamine-type amino acids; glycine, alanine, glutamic acid, Monoamine type amino acids such as taurine, aminocaproic acid, aminobenzoic acid, aminoisophthalic acid and sulfamic acid; or 2,2-dimethylolpropionic acid, 2,2-dimethylolbutyric acid, 2,2-dimethylolvaleric acid and the like Rubonic acid-containing polyol; adduct of iminodiacetic acid and glycidol, polyester polyol using 5-hydroxysulfoisophthalic acid, polycaprolactone polyol using carboxylic acid-containing polyol as initiator, polyester polyol or polycarbonate polyol and carboxylic acid-containing polyol Ester exchange products and the like can be mentioned.

The organic acids mentioned above have a number average molecular weight of 5
High molecular weight polyols (polyester polyols, polyether polyols, polycarbonate polyols, polyolefin polyols, etc.) of more than 00 to 10,000
The aforementioned low-molecular glycol, trimethylolpropane, low-molecular polyols such as glycerin, polyamines and the like,
A half ester mixture or a half amide mixture (containing a carboxyl group) obtained by reacting with a polycarboxylic anhydride can also be used.

For example, when a polyol is added to a dianhydride such as pyromellitic anhydride, two carboxylic acid groups are generated, so that a hydrophilic polar group can be introduced into the molecular chain of the polyester polyol. Other examples of the anionic hydrophilic group that can be used in the present invention include phosphoric acid.

The polyester polyol, which is one kind of the above-mentioned high molecular polyols, includes, for example, the above-mentioned low molecular polyols and phthalic acid, isophthalic acid, terephthalic acid, succinic acid, malonic acid, oxalic acid, glutaric acid, adipic acid, It can be obtained by known methods from polycarboxylic acids such as pimelic acid, suberic acid, azelaic acid, sebacic acid, maleic acid, fumaric acid, trimellitic acid, pyromellitic acid and their anhydrides.

The polyether polyol is obtained, for example, by an addition polymerization reaction of an alkylene oxide with a single or a mixture of two or more compounds having two or more active hydrogen groups such as the above-mentioned low molecular polyols and polyamines. Were given.

As the polycarbonate polyol, for example, a polyol obtained by removing phenol from a low-molecular polyol usable as the above-mentioned polyester polyol and diphenyl carbonate, or a polyol obtained by removing alcohol from the above-mentioned low-molecular polyol and dialkyl carbonate is used. The resulting polyol and the like can be mentioned.

Examples of the polyolefin polyol include hydroxyl-containing polybutadiene, hydroxyl-containing polyisoprene, hydroxyl-containing hydrogenated polybutadiene, hydroxyl-containing hydrogenated polyisoprene, hydroxyl-containing chlorinated polyethylene, and hydroxyl-containing chlorinated polypropylene.

Examples of the above-mentioned "neutralizing agent" constituting an anionic surfactant together with the above-mentioned organic acids include ammonia, ethylamine, trimethylamine, triethylamine, triisopropylamine, tributylamine, triethanolamine, N-methyldiethanolamine, N
-Organic amines such as phenyldiethanolamine, monoethanolamine, dimethylethanolamine, diethylethanolamine, morpholine, N-methylmorpholine, 2-amino-2-ethyl-1-propanol; alkali metals such as lithium, potassium and sodium; Inorganic alkalis such as sodium hydroxide and potassium hydroxide; and the like. Among them, from the viewpoint of improving the weather resistance and the water resistance after drying the coating film, those having high volatility which is easily dissociated by heat, for example, ammonia, or a lower amine having a total carbon number of an organic group of 9 or less (trimethylamine, And triethylamine.

(Cationic hydrophilic surfactant) The cationic hydrophilic surfactant described above is usually a compound containing at least one active hydrogen group capable of reacting with an isocyanate group (cationic hydrophilic polar group). Containing compound).
The cationic hydrophilic polar group-containing compound comprises, for example, a tertiary amine and one or more compounds selected from inorganic acids, organic acids, and quaternizing agents.

Examples of the tertiary amine include N-methyldiethanolamine, N-ethyldiethanolamine, N-alkyldiethanolamine having an alkyl chain having a carbon number larger than 2, N-phenyldiethanolamine, N-phenyldipropanolamine, -Methyldiisopropanolamine, N, N'-dihydroxyethylpropanolamine, triethanolamine, N,
N'-dimethylethanolamine, N-methyl-bis-
(3-aminopropyl) -amine, N-methyl-bis-
(2-aminopropyl) -amine and the like.

The above-mentioned inorganic or organic acid includes, for example,
Hydrochloric acid, acetic acid, lactic acid, cyanoacetic acid, phosphoric acid, sulfuric acid and the like. Examples of the quaternizing agent include dimethyl sulfate, benzyl chloride, bromoacetamide, chloroacetamide, and alkyl halides such as ethyl bromide, propyl bromide, and butyl bromide. Examples of the other compounds having a cationic hydrophilic polar group include cationic compounds such as primary amine salts, secondary amine salts, tertiary amine salts, and pyridinium salts.

Also, amphoteric compounds such as a reaction product of a tertiary amine-containing polyol with sulfobetaine, etc.
It can be used as a grading agent.

The hydrophilic surfactant has a hydrophilic group in the molecular skeleton and has an effect of imparting water dispersibility to the blocked isocyanate of the present invention. From the viewpoint of the reactivity and stability of the isocyanate group in the water-dispersible blocked isocyanate, the hydrophilic surfactant is preferably a nonionic.

(Hydrophobic organic compound having 7 or more carbon atoms) A hydrophobic organic compound having at least one active hydrogen group and having at least one active hydrogen group to be introduced into the water-dispersible blocked isocyanate composition of the present invention as required. Examples of the "active organic compound" include, for example,
Heptyl alcohol, benzyl alcohol, octyl alcohol, 2-ethyl-hexanol, methylbenzyl alcohol, caprylic alcohol, nonyl alcohol,
Decyl alcohol, undecyl alcohol, lauryl alcohol, tridecyl alcohol, myristyl alcohol
Higher alcohols having 7 or more carbon atoms, such as octylamine, octylamine, benzylamine, 2-ethyl-hexylamine, methylbenzylamine, capryl, and the like, such as benzyl, pentadecyl alcohol, cetyl alcohol, and cinnamyl alcohol. Amine, nonylamine, decylamine, undecylamine, laurylamine, tridecylamine,
Myristylamine, pentadecylamine, cetylamine, cinnamylamine, N-methylheptylamine, N
Monoamines having 7 or more carbon atoms such as -methyloctylamine and N-methylbenzylamine; α-oxypropionic acid, oxysuccinic acid, dioxysuccinic acid, ε-oxypropane-1,2,3-tricarboxylic acid, hydroxyacetic acid, α -Hydroxybutyric acid, hydroxystearic acid, ricinoleic acid, ricinoelaidic acid, ricinostearolic acid, salicylic acid, oxycarboxylic acid such as mandelic acid,
A hydroxyl group-containing ester comprising a monoalcohol such as methanol, ethanol, propanol, isopropanol, butanol, sec-butanol, or ter-butanol, and having a total carbon number of 7 or more; "organic acids or polymer polyols ( Polyester polyols, polyether polyols, polycarbonate polyols, and polyolefin polyols).

The above-mentioned hydrophobic organic compound has a hydrocarbon chain in its molecular skeleton, and is mixed with a water-dispersible blocked isocyanate into which the hydrophobic organic compound is introduced, and an aqueous solution and / or an aqueous emulsion contained in an aqueous emulsion. Since the compatibility with the molecular skeleton of the hydrophilic polymer is improved, gloss and sharpness when the isocyanate is formed into a coating film as an aqueous paint or the like are improved. Therefore, it is more effective that the “hydrocarbon chain” contained in the hydrophobic organic compound has a certain size, and more specifically, the hydrocarbon chain has 7 or more carbon atoms, It is preferably 12 or more.

Further, the "active hydrogen group" site of the hydrophobic organic compound to be reacted with the isocyanate group is preferably located near the center of the hydrophobic organic compound molecule rather than at the terminal of the hydrophobic organic compound. The reason for this is that, according to the findings of the present inventors, in the case where water is present in the system after the blocking agent is removed, the ability to protect the isocyanate group by a steric hindrance effect from water attack has been found. It is presumed to be further improved.

(Content of Low-Molecular Glycol, etc.) In the present invention, the content or introduction amount of low-molecular glycol (X)
Is 0.1% based on the isocyanate group terminal precursor.
wt% ≦ X ≦ 15 wt%, further 0.3 wt% ≦ X ≦ 1
It is preferable that 0 wt%, especially 0.5 wt% ≦ X ≦ 5 wt%.

If the amount (X) of the low-molecular glycol introduced is less than 0.1 wt%, there is a problem of poor compatibility with the water-soluble polymer solution or the aqueous emulsion, or a partially gelled product is produced during the synthesis of the blocked isocyanate. And the like tend to occur. On the other hand, when the amount (X) of the low-molecular glycol to be introduced exceeds 15 wt%, the characteristics of the isocyanurate structure cannot be sufficiently exhibited in the blocked isocyanate, and the improvement in weather resistance and heat resistance tends to be insufficient. Tend to be.

The content or introduction amount (Y) of the hydrophilic surfactant is based on the isocyanate group-terminated precursor.
0.1 wt% ≦ Y ≦ 50 wt%, further 0.5 wt% ≦
It is preferable that Y ≦ 45 wt%, particularly 1 wt% ≦ Y ≦ 40 wt%. If the amount (Y) of the hydrophilic surfactant introduced is less than 0.1 wt%, the dispersion stability in a water-soluble polymer solution or an aqueous emulsion becomes poor, and phenomena such as sedimentation tend to occur. Conversely, if the amount (Y) of the hydrophilic surfactant exceeds 50 wt%, the characteristics of the isocyanurate structure cannot be sufficiently exhibited, and the weather resistance and heat resistance tend to be insufficiently improved. There is.

When the hydrophobic compound is introduced, the compatibility with the aqueous resin is improved, but the effective NCO is reduced correspondingly. Therefore, it is preferable to determine the introduction amount in consideration of these factors.

The content or introduction amount (Z) of the hydrophobic organic compound is determined based on the isocyanate group-terminated precursor.
0 wt% ≦ Z ≦ 30 wt%, and further 0 wt% ≦ Z ≦ 25
wt%, particularly preferably 0 wt% ≦ Z ≦ 20 wt%. 30 wt% of the introduced amount (Z) of the hydrophobic organic compound
When the ratio exceeds, the characteristics of poor water dispersibility and the isocyanurate structure cannot be sufficiently exhibited, and the weather resistance and heat resistance tend to be insufficiently improved.

As described above, in the water-dispersible blocked isocyanate of the present invention, a hydrophilic surfactant is introduced into an organic isocyanate, and a low-molecular glycol (if necessary, a hydrophobic compound comprising an aliphatic compound or a fatty acid ester) is added. Organic compound) in a well-balanced manner,
It is possible to obtain a water-dispersible blocked isocyanate having both dispersion stability and compatibility with the molecular skeleton of a water-soluble polymer solution or aqueous emulsion.

The (average) number of functional groups (f) in the water-dispersible blocked isocyanate of the present invention is 2.0 to 4.2,
More preferably, it is 2.2 to 4.0. When the number of functional groups (f) is less than 2.0, the crosslinking efficiency tends to decrease. Conversely, when the number of the functional groups (f) exceeds 4.2, the number of the functional groups is too large, and the tendency to crosslink in the molecules of the resin of the base resin rather than between the molecules increases. Crosslinking efficiency tends to decrease.

The number of functional groups (f) can be suitably measured by the following method.

1. The blocked isocyanate composition is heated in an atmosphere of an inert gas to remove a blocking agent, a solvent, and the like.

2. NCO of remaining polyisocyanate
Measure the content.

3. The number average molecular weight of the remaining polyisocyanate is measured by GPC (polystyrene calibration curve).

4. The measured value of the NCO content and the measured value of the number average molecular weight are applied to the following formula to calculate the average number of functional groups.

F = NCO (wt%) / 42 × 1/100 × Mn = NCO (wt%) × Mn / 4200 f: average number of functional groups (“number average molecular weight of precursor”
NCO: Measured value of NCO content (wt%) Mn: Measured number average molecular weight 100 × 42 / NCO: Number average molecular weight per NCO group

(Production Method of Isocyanate Group Terminal Precursor) In the present invention, for example, the following method can be used as a production method for obtaining an isocyanate group terminal precursor.

(A) An isocyanurate-forming catalyst is added to an isocyanate-terminated prepolymer obtained by adding a low molecular weight glycol to an organic isocyanate to introduce an isocyanurate ring structure, and then a hydrophilic surfactant is added. (And, if necessary, a hydrophobic organic compound).

(B) At the same time as adding a low molecular weight glycol to the organic isocyanate and adding an isocyanurate-forming catalyst to introduce an isocyanurate ring structure, a hydrophilic surfactant (and, if necessary, a hydrophobic surfactant) is added. A reactive organic compound).

(C) After reacting an organic isocyanate with a low molecular weight glycol and a hydrophilic surfactant (and, if necessary, a hydrophobic organic compound), an isocyanurate-forming catalyst is added to the isocyanurate ring structure. How to introduce.

(D) An isocyanurate ring structure is formed by reacting an organic isocyanate with a low molecular weight glycol and a hydrophilic surfactant (and, if necessary, a hydrophobic organic compound), and simultaneously adding an isocyanurate-forming catalyst. How to introduce.

However, when it is preferable that the viscosity of the water-dispersible blocked isocyanate is lower, for example, when the viscosity of the water-soluble polymer solution and / or aqueous emulsion to be combined is low and the viscosity of the self-emulsifying polyisocyanate is high, the dispersibility is low. In the case where the reaction becomes worse and the workability is adversely affected, it is preferable to introduce an isocyanurate ring structure after reacting all the active hydrogen compounds to be used with the organic isocyanate as in the method (C). This is desirable because the viscosity of the water-dispersible blocked isocyanate decreases.

The reaction between an isocyanate group and a low molecular weight glycol, and the reaction between an isocyanate group and a hydrophilic surfactant or a hydrophobic organic compound can be carried out under ordinary urethanization conditions. The reaction temperature is suitably in the range of 20 to 150 ° C.

The isocyanurate-forming reaction includes, for example, tertiary amines, alkyl-substituted ethyleneimines, tertiary alkylphosphines, which are isocyanurate-forming catalysts;
Metal salts of acetylacetone, metal salts of various organic acids and the like are used alone or in combination, and if necessary, a co-catalyst such as a phenolic hydroxyl group-containing compound or an alcoholic hydroxyl group-containing compound is used.
At a reaction temperature of ~ 90 ° C, in the absence of a solvent, or an inert solvent commonly used in the polyurethane industry, for example, an aromatic solvent such as toluene and xylene, a ketone such as methyl ethyl ketone and methyl isobutyl ketone, an ethyl acetate and a butyl acetate. Glycols such as ester, propylene glycol methyl ether acetate, diethylene glycol butyl ether acetate, ethyl-3-ethoxypropionate, etc.
Polyol or DOP which is liquid at the reaction temperature in the presence of the luster ester system or, if necessary,
It can be carried out in a plasticizer such as (dioctyl phthalate).

After the above isocyanuration reaction, the catalyst is deactivated by using a terminator such as phosphoric acid, methyl paratoluenesulfonate, sulfur, etc.
The reaction can be stopped.

(Blocking Agent) The blocking agent used in the present invention is not particularly limited, and one or more known agents can be appropriately selected and used. As the blocking agent,
For example, phenol-based, alcohol-based, active methylene-based, mercaptan-based, acid amide-based, lactam-based, acid imide-based, imidazole-based, urea-based, oxime-based, and amine-based compounds can be used.

More specifically, for example, phenolic compounds such as phenol, cresol, ethylphenol, and butylphenol; 2-hydroxypyridine, butylcellosolve, propylene glycol monomethyl ether, ethylene glycol, benzyl alcohol, methanol, ethanol , N-butanol,
Alcohol compounds such as isobutanol and 2-ethylhexanol; active methylene compounds such as dimethyl malonate, diethyl malonate, methyl acetoacetate, ethyl acetoacetate and acetylacetone; mercaptan compounds such as butyl mercaptan and dodecyl mercaptan; acetanilide; Acid amide compounds such as acetic acid amide; lactam compounds such as ε-caprolactam, δ-valerolactam, γ-butyrolactam; acid imide compounds such as succinimide and maleic imide; imidazole such as imidazole and 2-methylimidazole Urea compounds such as urea, thiourea and ethylene urea; formaldoxime, acetoaldoxime, acetone oxime, methyl ethyl ketoxime, methyl isobutyl ketoxime, cyclohexanone oxide Oxime compounds such as shims;
Examples include amine compounds such as diphenylaniline, aniline, carbazole, ethyleneimine, and polyethyleneimine.

Among the above blocking agents, methyl ethyl ketoxime, ε-caprolactam, and 2-ethylhexanol are particularly preferably used from the viewpoint of versatility, simplicity of production, and workability.

(Reaction between Blocking Agent and Precursor) The water-dispersible blocked isocyanate composition of the present invention is obtained, for example, by reacting the above-described isocyanate group-terminated precursor with a blocking agent (blocking reaction). be able to. The reaction between the blocking agent and the isocyanate group-terminated precursor can be carried out according to ordinary blocking reaction conditions of 20 to 200 ° C.

In order to promote the blocking reaction, the amount of the blocking agent to be charged is 1.
A molar amount of 0 to 1.5 times is preferred. This blocking reaction can be carried out irrespective of the presence or absence of a solvent. However, if necessary, an inert solvent or catalyst known or commonly used in the urethane industry can be used.

As described above, the blocking agent can be reacted simultaneously with the hydrophilic surfactant (which is a component of the isocyanate group-terminated precursor) and the hydrophobic organic compound. Further, after the blocking agent is reacted with the isocyanate group-terminated prepolymer, a hydrophilic surfactant or a hydrophobic organic compound can be introduced.

The water-dispersible blocked isocyanate composition of the present invention may contain, if necessary, known additives such as pigments.
Dispersion stabilizer, viscosity modifier, leveling agent, anti-gelling agent, light stabilizer, antioxidant, ultraviolet absorber, heat resistance improver, inorganic and organic filler, plasticizer, lubricant, antistatic agent, reinforcing material , A catalyst and the like can be added.

(Aqueous resin) The aqueous resin which can be used in combination with the water-dispersible blocked isocyanate composition of the present invention includes an aqueous solution of a water-soluble polymer, an aqueous dispersion in which the water-dispersible polymer is dispersed in water, and an aqueous emulsion. And aqueous suspensions. Preferred types of the aqueous resin in the present invention are an aqueous dispersion of a water-soluble polymer in which the dispersoid (solute) is a liquid, and an aqueous dispersion in which the water-dispersible polymer is dispersed in water, in consideration of the reactivity with the isocyanate group. Aqueous emulsions are preferred.

The solution, dispersion, emulsion, and suspension are as described below.

Solution: A solution in which a solute is completely dissolved in a solvent.

Dispersion: The solute is dispersed without dissolving in a solvent, and has an average particle diameter of 0.001 to 0.001.
One having a thickness of about 0.1 μm and a dispersoid being a liquid.

Emulsion: A solute in which a solute is dispersed without being dissolved in a solvent, the average particle size of the dispersoid is about 0.1 μm or more, and the dispersoid is a liquid.

Suspension: A solute that is dispersed without being dissolved in a solvent and that is a solid.

(Water-Soluble Polymer) The polymer constituting the water-soluble polymer solution which can be used in combination with the water-dispersible blocked isocyanate composition of the present invention may be any known water-soluble polymer without particular limitation. Alternatively, two or more types can be appropriately selected.

In terms of versatility, polyvinyl alcohol
Water-soluble ethylene-vinyl acetate copolymer, polyethylene oxide, water-soluble acrylic resin, water-soluble epoxy resin, water-soluble cellulose derivative, water-soluble polyester and water-soluble lignin derivative, etc., are preferable as the water-soluble polymer. It can be used for

(Aqueous Emulsion) The aqueous emulsion that can be used in the present invention is appropriately selected from known aqueous emulsions (for example, so-called latex and emulsion) without any particular limitation. Can be.

Examples of the aqueous emulsion include rubber latexes such as styrene butadiene copolymer latex, acrylonitrile butadiene copolymer latex, methyl methacrylate butadiene copolymer latex, chloroprene latex and polybutadiene latex, and polyacrylic latex. Examples include acid ester latex, polyvinylidene chloride latex, polybutadiene latex, and those obtained by carboxyl-modifying these latexes. Further, polyvinyl chloride emulsion, urethane acrylic emulsion, silicone acrylic emulsion, vinyl acetate acrylic emulsion, urethane emulsion, acrylic emulsion and the like can also be used.

Fluorine (resin) emulsions having excellent weather resistance and stain resistance have poor solvent resistance due to non-crosslinking (when used alone). By using together,
Not only can the weather resistance and stain resistance be further improved, but also the solvent resistance can be improved.

(Aqueous Dispersion, Aqueous Suspension) In the present invention, known aqueous dispersions and aqueous suspensions can be used as long as they have an active hydrogen group.

In the aqueous coating composition and the aqueous adhesive composition of the present invention, the isocyanate group blocked by the blocking agent in the water-dispersible block isocyanate composition is considered from the viewpoint of physical properties such as weather resistance. And the molar ratio of active hydrogen groups in the solid content of the aqueous resin is (molar number of isocyanate groups):
(Mole number of moles of active hydrogen group) = 1: 9 to 9: 1, preferably 4: 6 to 6: 4.

The water-dispersible blocked isocyanate composition may be added directly to the main ingredient (aqueous resin), or, if necessary, a form in which the water-dispersible blocked isocyanate composition is once dispersed in water, or It may be added to the base in a form diluted with a solvent commonly used in the urethane industry.

The aqueous coating composition or the aqueous adhesive composition of the present invention can be used for a wide variety of applications. Such applications include, for example, paints and adhesives of metals, woodwork, plastics, fibers, woody materials, paper, and porous inorganic materials.

(Viscosity) From the viewpoint of workability, the water-dispersible blocked isocyanate composition of the present invention has a (solid content of 80%
100 to 100,000 m)
Pa · s / 25 ° C, 150-80,000 mPa
· S / 25 ° C, especially 200 to 50,000 mPa · s /
It preferably has a viscosity range of 25 ° C.

The viscosity is preferably measured by the following measuring method.

<Measurement method of viscosity>
It is measured by a method according to SK5400-1990. The outline of the measuring method is as follows.

That is, a sample whose viscosity is to be measured at a temperature adjusted to 25 ° C. is placed in a beaker of about 500 ml (inner diameter 85).
mm and a depth of about 120 mm)
Insert until it is 0 mm or more. Next, the viscosity of the sample in the beaker is measured using a single cylinder rotational viscometer (SB type viscometer, for example, digital viscometer DVL-BII, manufactured by Tokimec Co., Ltd.). The number of rotors to be selected and the torque or number of rotations are specified in JIS K5
Determined according to 400-1990. At this time, the indicator of the rotational viscometer is at the scale index θ at a fixed position on the rotating scale plate (the indicator is preferably at a position of about 20 to 100% in order to reduce errors). From the conversion multiplier K (determined by the rotor number and the rotor speed) specified in (Table 10) of JIS K5400-1990, and the viscosity η (mP
a · s {cP}).

Η = K × θ (effective NCO content) From the viewpoint of physical properties such as weather resistance, the water-dispersible blocked isocyanate composition of the present invention (in the state of a solution of an organic solvent having a solid content of 80%) 4.0-15.0
wt%, furthermore 4.5 to 14.5 wt%, especially 5.0 to
Preferably, it has an effective NCO content range of 14.0 wt%. This effective NCO content indicates all NCO groups, including NCO groups that are deblocked by a given heating.

The effective NCO content is preferably measured by the following measuring method.

<Method for Measuring Effective NCO Content> (1) Samples to be measured for effective NCO content: about 1.0 to 2.
0 g is precisely weighed into an Erlenmeyer flask (300 ml in internal volume) having a “grinding” opening.

(2) 0.5 mol was added to the Erlenmeyer flask.
/ L of dibutylamine-monochlorobenzene solution 25m
After the addition of 1 and the solvent and zeolite, a "striking" bulb condenser fitted to the opening of the flask is attached. At this time, the following solvent is used as the solvent.

<Selection of Solvent> When the blocking agent is MEK (methyl ethyl ketone) oxime: xylene ε-caprolactam: ortho-dichlorobenzene 1-octanol: ethoxybutyl acetate (3) On a previously prepared heating plate, Place the above Erlenmeyer flask and wait 3 seconds after the solvent in the flask starts to boil.
Incubate for 0 minutes.

(4) Thereafter, the Erlenmeyer flask was removed from the heating plate and cooled to room temperature, and then 20 to 30 ml of methanol was poured from above the rubbed spherical tube cooler, and the inner wall of the cooler was washed with the methanol. Wash off.

(5) After removing the condenser from the Erlenmeyer flask, 100 ml of methanol and one drop of bromophenol blue indicator were put into the Erlenmeyer flask, and 0.5 mol / l of the content of the flask was added. Perform back titration using hydrochloric acid standard solution. At this time, the titer of the hydrochloric acid standard solution required for titration of the sample is defined as A (ml).

(6) Except that the above-mentioned heating is not performed, the same operation as in the above (1) to (4) is performed to obtain a “blank”
Obtain a sample. The blank is titrated as in (5) above. At this time, the titer of the hydrochloric acid standard solution required for the blank titration is defined as B (ml).

(7) The end point of the titration is
The point where the blue color of the blue indicator changes to yellow.

(8) The effective NCO is calculated using the following formula.
Calculate the content.

Effective NCO content (wt%) = {(BA)
× 42 × 0.5 × f} × 100 ° (S × 1000) In the above formula, A: titration (ml) of 0.5 mol / l hydrochloric acid standard solution required for titration of sample B: titration of blank The required titration amount (ml) of the required 0.5 mol / l hydrochloric acid standard solution f: the factor S of the 0.5 mol / l hydrochloric acid standard solution S: the sampled amount (g) is shown.

(Dispersion Stability) From the viewpoint of the appearance of the coating film and workability, the water-dispersible blocked isocyanate composition of the present invention has the following properties: When observed with the naked eye, it is preferable to have a dispersion stability of being uniform without causing precipitation.

<Method of Measuring Dispersion Stability> (1) A sample of a water-dispersible blocked isocyanate composition whose dispersion stability is to be measured and distilled water having the same weight as the isocyanate are placed in the same container (glass flask). .

(2) Using a stirrer, 100 rpm ×
Under the condition of 60 seconds, the contents of the flask are rapidly stirred to disperse the isocyanate in water.

(3) After the above dispersion is completed, the dispersion is allowed to stand for 30 minutes, and then the appearance of the dispersion is visually checked.

(4) In the above-mentioned macroscopic observation, when no precipitation is observed in the dispersion and the dispersion is a uniform solution or dispersion, the dispersion is considered to have "dispersion stability".

(Gloss) In view of the appearance of the coating film, the water-dispersible blocked isocyanate composition of the present invention has an incident angle of 60
°, the gloss at a reflection angle of 60 ° is 60 to 100, and even 6
It is preferably in the gloss range of 5 to 100, especially 70 to 100. The gloss is preferably measured after the isocyanate of the present invention is used as a gloss measuring paint by the following method.

(Gloss Measurement Method) (1) Using the blocked isocyanate composition of the present invention to be measured for gloss as a curing agent, a paint for gloss measurement is prepared from the following raw materials.

Main agent: Armatex WA911 (AL
MAtex WA911) Solid content = 60 wt% Acid value = 29 mgKOH / g (manufactured by Mitsui Toatsu Chemicals Co., Ltd.) Curing agent: block isocyanate composition of the present invention, etc. Pigment: titanium oxide (manufactured by Ishihara Sangyo Co., trade name: Taipek R-970 Neutralizing agent: tertiary amine (triethylamine; manufactured by Kishida Chemical Co., Ltd., reagent first grade) Diluent: water (2) Calculation of blending part of each component Let A be the number of parts (parts by weight) of the main agent (solution).

Pigment (parts) = 0.7 × A Curing agent (parts) in terms of solid content = 1.1 × A / effective NCO
(Wt%) Neutralizing agent (parts) = A × acid value of main agent (mg KOH / g) × molecular weight of neutralizing agent / 56 water (parts) = 1.2 × A—neutralizing agent (parts) (3) The paint prepared with the above composition is applied to an aluminum plate (trade name: A1050P, manufactured by Nippon Test Panel Kogyo Co., Ltd.) using a bar coater so that the thickness of the paint after drying is 30 to 40 μm, and then heated. I do. (The heating conditions vary depending on the type of the blocking agent. For specific heating conditions, refer to the examples.) The gloss of the coating film thus obtained was measured using a gloss meter (Ericsen Co., trade name: Pico Using a gloss master model 500), the incident angle is 60 ° and the reflection angle is 60 °.
Measure under ° condition.

[0123]

EXAMPLES Next, examples of the present invention and comparative examples will be described in detail, but the present invention is not limited to these examples. Unless otherwise specified, “parts” and “%” in the examples mean “parts by weight” and “% by weight”, respectively.

Synthesis Example 1 ( Synthesis of Isocyanate Group-Terminal Precursor) HDI (hexamethylene-methanol) was placed in a reactor (made of glass, 500 ml in internal volume) equipped with a stirrer, a thermometer, a nitrogen seal tube, and a cooler. 1,6-diisocyanate) 300 parts,
After charging 2.8 parts of 1,3-butanediol, the inside of the reactor was purged with nitrogen, heated to a reaction temperature of 80 ° C. with stirring, and reacted at the same temperature for 2 hours.

The content of the isocyanate group in this reaction solution was measured and found to be 48.6%. Next, 0.06 part of potassium caprate as a catalyst and 0.3 part of phenol as a cocatalyst were added, and an isocyanurate-forming reaction was carried out at 60 ° C. for 6 hours. Phosphoric acid was added as a terminator to this reaction solution at 0.0
42 parts were added, and the mixture was stirred at the reaction temperature for 1 hour.
It was removed by thin-film distillation at 20 ° C. and 0.01 Torr. The obtained isocyanate-terminal precursor was a pale yellow transparent liquid, an isocyanate group content of 20.8%, and a viscosity of 2
500 cP / 25 ° C., free HDI content 0.3%, functional group 3.8, low molecular glycol content 2.6%,
FT-IR (PerkinElmer, trade name: FT-I
The presence of an isocyanate group, an isocyanurate group and a urethane group was confirmed by R1600 series) and ¹³ C-NMR (manufactured by Varian, trade name: FT-NMR Unity 500). The yield was 35%.

Synthesis Example 2 HDI 30 was placed in the same reactor as used in Synthesis Example 1.
0 parts and 4.0 parts of 2-n-butyl-2-ethyl-1,3-propanediol were added. After the inside of the reactor was replaced with nitrogen, the mixture was heated to a reaction temperature of 80 ° C. while stirring. Then, the reaction was carried out at the same temperature for 2 hours. The content of the isocyanate group in the obtained reaction solution was measured and found to be 48.6%.

Next, 0.06 parts of potassium caprate as a catalyst and 0.3 parts of phenol as a co-catalyst were added.
The reaction (isocyanuration reaction) was carried out at 60 ° C. for 4.5 hours. Next, 0.042 parts of phosphoric acid was added as a terminator to the obtained reaction solution, and the mixture was stirred at the above-mentioned reaction temperature (80 ° C.) for 1 hour, and free HDI was added at 120 ° C. and 0.01 Torr.
It was removed by thin-film distillation under a pressure of r.

The isocyanate group-terminated precursor obtained is
Pale yellow transparent liquid, isocyanate group content 21.3%,
Viscosity 2600 cP / 25 ° C., free HDI content 0.5
%, Number of functional groups 3.6, low molecular glycol content 5.3%
FT-IR and ¹³ C-NMR confirmed the presence of isocyanate, isocyanurate and urethane groups. The yield was 25%.

Synthesis Example 3 HDI 30 was placed in a reactor similar to that used in Synthesis Example 1.
0 parts and 0.7 parts of neopentyl glycol were charged, and the inside of the reactor was replaced with nitrogen.
And reacted at the same temperature for 2 hours. The isocyanate group content of this reaction solution was 49.6%.

Next, potassium caprate 0.1.
06 parts and 0.3 parts of phenol as a co-catalyst were added,
The isocyanurate-forming reaction was performed at 4.5 ° C. for 4.5 hours. 0.042 parts of phosphoric acid as a terminator was added to the reaction solution, and the mixture was further stirred at the above reaction temperature (80 ° C.) for 1 hour.
I was removed by thin-film distillation at 120 ° C. and 0.01 Torr.

The isocyanate group-terminated precursor obtained is
Pale yellow transparent liquid, isocyanate group content 21.2%,
Viscosity 2300 cP / 25 ° C., free HDI content 0.4
%, Number of functional groups 3.8, low molecular glycol content 0.8%
FT-IR and ¹³ C-NMR confirmed the presence of isocyanate, isocyanurate and urethane groups. The yield was 30%.

Synthesis Example 4 HDI 30 was placed in a reactor similar to that used in Synthesis Example 1.
0 parts, 2,2,4-trimethyl-1,3-pentaneddiol, 3.9 parts, and polyoxyethylene methyl ether (hydroxyl value 140 mgKOH / g, manufactured by Toho Chiba Kogyo; hereinafter, "methoxy PEG # 400") ). After the inside of the reactor was replaced with nitrogen, the mixture was heated to a reaction temperature of 80 ° C with stirring, and reacted at the same temperature for 2 hours. When the isocyanate group content of this reaction solution was measured,
45.6%.

Next, potassium caprate 0.1.
06 parts and 0.3 parts of phenol as a co-catalyst were added,
The isocyanurate-forming reaction was performed at 4.5 ° C. for 4.5 hours. 0.042 parts of phosphoric acid as a terminator was added to the reaction solution, and the mixture was further stirred at the above reaction temperature (80 ° C.) for 1 hour.
I was removed by thin-film distillation at 120 ° C. and 0.01 Torr.

The obtained isocyanate group-terminated precursor is
Pale yellow transparent liquid, isocyanate group content 17.2%,
Viscosity 730 cP / 25 ° C., free HDI content 0.4%,
The number of functional groups is 3.4, the content of low molecular glycol is 3.0%, the content of hydrophilic surfactant is 12.4%, and FT-I
From R and ¹³ C-NMR, the presence of an isocyanate group, an isocyanurate group and a urethane group was confirmed. The yield was 40%.

Example 1 (Synthesis of Water-Dispersible Blocked Isocyanate) In a reactor similar to that used in Synthesis Example 1, 100 parts of the isocyanate group-terminated precursor obtained in Synthesis Example 1 was added.
0 was added, and the temperature was raised to 75 ° C.
), The NCO content was 16.5%, the viscosity was 2730 cP / 25 ° C, the number of functional groups was 3.5, the content of low molecular glycol was 2.2%, and the hydrophilic surfactant was Of 13.7% was obtained.

The isocyanate group-terminated precursor was added to 100
Part and methyl ethyl ketone (hereinafter abbreviated as MEK) 3
And 3.7 parts at room temperature. Further, 34.9 parts of methyl ethyl ketoxime was put into the dropping funnel, and the above isocyanate group-terminated precursor / MEK was stirred for 30 minutes.
After dropping over minutes, the mixture was reacted at 70 ° C. for 2 hours. The effective NCO content was 9.8%, and the viscosity was 650 cP / 25.
C., a solid content of 80%, and a pale yellow transparent water-dispersible blocked isocyanate WBI-1 was obtained.

Example 2 In a reactor similar to that used in Synthesis Example 1, 100 parts of the isocyanate group-terminated precursor obtained in Synthesis Example 1 and methoxy P
12 parts of EG # 400 and ricinoleic acid methyl ester (hydroxyl value 166, manufactured by Ogura Gosei Kogyo Co., Ltd .; hereinafter referred to as “K-P
ON 180 ". ), And the mixture was heated to 75 ° C and reacted for 3 hours while maintaining the temperature (75 ° C). As a result, the NCO content was 16.4% and the viscosity was 2920.
cP / 25 ° C., the number of functional groups is 3.5, the content of low molecular weight glycol is 2.2%, and the content of hydrophilic surfactant is 10.3
%, An isocyanate group-terminated prepolymer having an aliphatic compound content of 3.4%.

100 parts of this isocyanate group-terminated prepolymer and 33.7 parts of MEK were mixed at room temperature. To the resulting mixture was added methyl ethyl ketoxime 3
After dropping 4.7 parts from the dropping funnel over 30 minutes, 7
When reacted at 0 ° C. for 2 hours, the effective NCO content was 9.7.
%, A viscosity of 670 cP / 25 ° C., a solid content of 80%, and a light yellow transparent water-dispersible blocked isocyanate WBI-2 was obtained.

Example 3 In a reactor similar to that used in Synthesis Example 1, 100 parts of the isocyanate group-terminated precursor obtained in Synthesis Example 1 and methoxy P
When 20 parts of EG # 400 and 18 parts of K-PON180 were added, the temperature was raised to 75 ° C., and the reaction was carried out for 3 hours while maintaining the temperature (75 ° C.). The NCO content was 11.9.
%, Viscosity 3050 cP / 25 ° C., number of functional groups 3.0, low molecular glycol content 1.9%, hydrophilic surfactant content 14.5%, aliphatic compound content 13.0
% Of an isocyanate group-terminated prepolymer was obtained.

100 parts of this isocyanate group-terminated prepolymer, 33.4 parts of MEK and 33.7 parts of ε-caprolactam were added and heated to 70 ° C. while stirring and mixing. After reacting at 70 ° C. for 3 hours, dibutyltin dilaurate (hereinafter abbreviated as “DBTDL”) is added in an amount of 0.01.
And reacted at 70 ° C. for 10 hours.
A pale yellow, transparent, water-dispersible blocked isocyanate WBI-3 having a CO content of 7.1%, a viscosity of 1,000 cP / 25 ° C., a solid content of 80% and a light yellow color was obtained.

Example 4 In a reactor similar to that used in Synthesis Example 1, 100 parts of the isocyanate group-terminated precursor obtained in Synthesis Example 1 and methoxy P
24 parts of EG # 400 and 21.6 of K-PON180
The mixture was heated to 75 ° C., and reacted for 3 hours while maintaining the temperature (75 ° C.).
0.7%, viscosity 3500 cP / 25 ° C., number of functional groups 2.
8. An isocyanate group-terminated prepolymer having a low molecular glycol content of 1.8%, a hydrophilic surfactant content of 16.5% and an aliphatic compound content of 14.8% was obtained.

100 parts of this isocyanate group-terminated prepolymer, 32.6 parts of MEK, and 30.3 parts of ε-caprolactam are added, and the mixture is heated to 70 ° C. while stirring and mixing, and is heated at the temperature (70 ° C.) for 3 hours. After reacting, DBTD
L was added and reacted at 70 ° C. for 10 hours. The effective NCO content was 6.6%, and the viscosity was 880 cP / 25.
C., a solid content of 80%, and a pale yellow transparent water-dispersible blocked isocyanate WBI-4 was obtained.

Example 5 In a reactor similar to that used in Synthesis Example 1, 100 parts of the isocyanate group-terminated prepolymer obtained in Synthesis Example 2 and propylene glycol methyl ether acetate (hereinafter abbreviated as PMA) were added. 36.1 parts, 4.4 parts of triethylamine, 5.8 parts of dimethylolpropionic acid, 2 parts of K-PON180, and 56.7 parts of 2-ethylhexyl alcohol were added, and the mixture was stirred and mixed at 75 ° C.
Until heated. When the reaction was carried out for 3 hours while maintaining the temperature (75 ° C.), the effective NCO content was 8.5%, and the viscosity was 1
2100 cP / 25 ° C., solid content 80%, the number of functional groups of the isocyanate group-terminated precursor when all blocking agents are dissociated is 3.9, the content of low molecular glycol is 4.9%,
Water-dispersible blocked isocyanate W having a hydrophilic surfactant content of 5.4% and an aliphatic compound content of 1.8%
BI-5 was obtained.

Example 6 In a reactor similar to that used in Synthesis Example 1, 100 parts of the isocyanate group-terminated prepolymer obtained in Synthesis Example 3, 44.3 parts of PMA, and polycaprolactone triol (PLACCEL305, hydroxyl group Value: 305, manufactured by Daicel Chemical Industries, Ltd.) and maleic anhydride at a ratio of 1: 1 (molar ratio).
27.8 parts of the reaction product and 2-ethylhexyl alcohol 5
Then, the mixture was heated to 75 ° C. while stirring and mixing, and reacted for 3 hours while maintaining the temperature at 75 ° C. And N,
1.9 parts of N'-dimethylethanolamine was added and 70
After stirring at 30 ° C. for 30 minutes, the effective NCO content was 7.6.
%, Viscosity 5,300 cP / 25 ° C., solid content 80%, the number of functional groups of the isocyanate group-terminated precursor is 4.1 when all blocking agents are dissociated, the content of low molecular glycol is 0.6%, hydrophilicity A water-dispersible blocked isocyanate WBI-6 having a surfactant content of 21.8% was obtained.

Example 7 In a reactor similar to that used in Synthesis Example 1, 100 parts of the isocyanate group-terminal precursor obtained in Synthesis Example 4, 37.2 parts of butyl carbitol acetate, and ε-caprolactam 48.6 parts, and the mixture was heated to 70 ° C. while stirring and mixing, and reacted at the temperature (70 ° C.) for 3 hours.
After adding 0.01 parts of BTDL and reacting at 70 ° C. for 10 hours, the effective NCO content was 9.3% and the viscosity was 1200 c.
P / 25 ° C., solid content 80%, the number of functional groups of the isocyanate group-terminated precursor when all the blocking agents are dissociated is 3.
4. A pale yellow transparent water-dispersible blocked isocyanate WBI-7 having a low molecular glycol content of 3.0% and a hydrophilic surfactant content of 12.4% was obtained.

Comparative Example 1 A water-dispersible blocked isocyanate WBI-8 was obtained in the same manner as in Example 1, except that 1,3-butanediol was not used.

Comparative Example 2 In a reactor similar to that used in Synthesis Example 1, 100 parts of the isocyanate group-terminated precursor obtained in Synthesis Example 3 and 105 parts of methoxy PEG # 400 were added. The reaction was conducted for 3 hours while maintaining the temperature (75 ° C.). The NCO content was 5.0%, and the viscosity was 4100 cP /
An isocyanate group-terminated prepolymer having a temperature of 25 ° C., a functional group number of 1.8, a low molecular weight glycol content of 0.4%, and a hydrophilic surfactant content of 51.2% was obtained.

100 parts of this isocyanate group-terminated prepolymer and 12.3 parts of MEK were mixed at room temperature. Furthermore, methyl ethyl ketoxime 1 was added to the mixture.
After dropping 0.6 part from the dropping funnel over 30 minutes, 7
When reacted at 0 ° C. for 2 hours, the effective NCO content was 4.1.
%, A viscosity of 830 cP / 25 ° C., a solid content of 90%, and a pale yellow transparent water-dispersible block isocyanate WBI-9 was obtained.

The above Examples 1 to 7 and Comparative Example 1,
The results obtained in Example 2 are summarized in the following (Table 1) and (Table 2).

[0150]

[Table 1]

[0151]

[Table 2] The meanings of the abbreviations in (Table 1) and (Table 2) are as follows.

Mo: methyl ethyl ketone oxime Cp: ε-caprolactam Oc: 2-ethylhexyl alcohol Examples 8 to 14 and Comparative Examples 3 and 4 (Preparation of water-based coating composition) Examples 1 to 7 and Comparative Example 1 Using the water-dispersible polyisoacine obtained in 2, a water-based coating composition shown in the following (Table 3) and (Table 4) was prepared.

[0153]

[Table 3]

[0154]

[Table 4] Abbreviations in the above (Table 3) and (Table 4) mean:
It is as follows.

Artemax WA911: Aqueous solution of acrylic resin (manufactured by Mitsui Toatsu Chemicals, Inc.) DMEA: N, N-dimethyl-N-ethanolamine TEA: Triethylamine [Coating film test] The above (Table 3) and (Table 4) The indicated "paint" composition was applied to an aluminum plate (manufactured by
(Trade name: A1050P), and coated with a bar coater so as to have a dry film thickness of 30 to 40 µm, and then heat-treated under conditions suitable for each water-dispersible polyisocyanate. The heat treatment conditions of the coating composition using each of the water-dispersible block isocyanate compositions are as follows.

<Conditions of Heat Treatment> Examples 8 and 9 and Comparative Examples 3 and 4 140 ° C. × 20 minutes Examples 10, 11, and 14 160 ° C. × 20 minutes Examples 12 and 13 180 ° C. × 20 minutes The gloss was measured using a gloss meter at a specular gloss at an incident angle of 60 degrees and a reflection angle of 60 degrees. The water resistance of the coating film was visually observed after immersing the coating film in tap water at 20 ° C. for one day. The results obtained are shown in the above (Table 4).

From the above (Table 4), it is understood that by introducing a low molecular weight glycol into the self-emulsifying type polyisocyanate, the compatibility with the resin in the main agent was improved, and the gloss was improved. Let's do it.

[0158]

[Table 5] The meaning of each symbol in the above (Table 5) is as follows.

[0159]

Example 15 [Preparation of water-based adhesive composition] (Production of urethane emulsion) Nipporan was placed in a reactor (made of glass, internal volume 2000 ml) equipped with a stirrer, thermometer, nitrogen seal tube, and condenser. 252.3 parts of 980N (polycarbonate-based polyol, number average molecular weight 2000, manufactured by Nippon Polyurethane Industry) and 61.1 parts of IPDI were charged, the temperature was raised to 75 ° C, and the temperature was maintained (75 ° C). For 1 hour. Then, after cooling the obtained reaction solution to 40 ° C, dimethylolpropionic acid 1 was added.
6.8 parts, 12.7 parts of triethylamine, and 128.8 parts of acetone were added and reacted for 3 hours to obtain a reaction solution having an NCO content of 0.45%.

Further, 191.8 parts of acetone and 3.1 parts of monoethanolamine were added to the reaction solution, and the mixture was added at 30 ° C.
For 20 minutes. Water 777.
7 parts and stirred at high speed to convert the phase from W / O type to O / W type. Then, acetone was distilled off from this solution using a rotary evaporator (trade name: RE47, manufactured by Yamato Scientific Co., Ltd.) at a temperature of 50 ° C. and a reduced pressure of 150 to 300 Torr, and the solid content was 30.0% and the viscosity was 540 cP / 2
A 5 ° C. urethane emulsion was obtained.

Using the urethane emulsion obtained above and the water-dispersible block isocyanate obtained in Example and Comparative Example 2, an aqueous adhesive composition shown in the following (Table 6) was prepared.

[0163]

[Table 6]

[Evaluation of Adhesive Strength] An aluminum plate having a thickness of 3 mm,
A 3 mm-thick bond steel plate was degreased with trichloroethylene, and the composition shown in the above (Table 5) was applied on these plates so that the dry film thickness became 40 to 50 μm.

Then, predrying was carried out at 80 ° C. for 5 minutes, and the above-mentioned respective plates of the same kind were overlapped so that air bubbles did not enter (the above composition was applied to only one of the overlapped plates), and 25 kg / Cm2 under pressure and heat-treated under conditions suitable for each water-dispersible polyisocyanate. The heating conditions of the adhesive using each of the water-dispersible blocked isocyanate compositions are as follows.

<Conditions of Heat Treatment> Example 15 and Comparative Example 5 140 ° C. × 20 min. Example 16 160 ° C. × 20 min.
Adhesive strength (kgf / 25 mm) was measured at a tensile speed of 100 mm / min using a tensile strength tester (trade name: Tensilon UTM-500, manufactured by Orientec) according to K6854. The results obtained are shown below (Table 7).

[0167]

[Table 7]

From the above (Table 7), it can be easily understood that the adhesive strength was increased by introducing the low molecular weight glycol into the water-dispersible block isocyanate composition in a well-balanced manner.

[0169]

As described above, according to the present invention, there is provided a blocked isocyanate composition comprising an isocyanate group-terminated precursor and a blocking agent for blocking a free isocyanate group of the precursor; The body contains at least an organic diisocyanate, a low molecular weight glycol, and a hydrophilic surfactant having at least one active hydrogen group; and the precursor has an isocyanurate ring structure, and has an average number of functional groups (f ) Is 2.0 ≦ f ≦ 4.
2. The content (X) of the low molecular glycol is 0.5 wt% ≦
A water-dispersible blocked isocyanate composition is provided, wherein X ≦ 15 wt% and the content (Y) of the hydrophilic surfactant is 0.1 wt% ≦ Y ≦ 50 wt%.

According to the present invention, there is further provided a blocked isocyanate composition comprising an isocyanate group-terminated precursor and a blocking agent for blocking a free isocyanate group of the precursor;
An organic diisocyanate, a low molecular weight glycol, a hydrophilic surfactant having at least one active hydrogen group, and at least a hydrophobic organic compound having at least one active hydrogen group and having 7 or more carbon atoms; and The precursor has an isocyanurate ring structure and the average number of functional groups (f) is 2.0 ≦ f
≦ 4.2, content of low molecular glycol (X) is 0.5w
t% ≦ X ≦ 15 wt%, hydrophilic surfactant content (Y) is 0.1 wt% ≦ Y ≦ 50 wt%, and hydrophobic organic compound content (Z) is 0 wt% <Z ≦ 30 wt%. A water-dispersible blocked isocyanate composition is provided.

According to the present invention, there is further provided a blocked isocyanate composition comprising an isocyanate group-terminated precursor and a blocking agent for blocking a free isocyanate group of the precursor;
At least an organic diisocyanate, a low molecular glycol, and a hydrophilic surfactant having at least one active hydrogen group; and wherein the blocked isocyanate composition is 100% in a solution of an organic solvent having a solid content of 80%. ~ 100,
A water-dispersible blocked isocyanate composition having a viscosity of 000 mPa · s / 25 ° C. is provided.

According to the present invention, there is further provided a blocked isocyanate composition comprising an isocyanate group-terminated precursor and a blocking agent for blocking a free isocyanate group of the precursor;
At least an organic diisocyanate, a low molecular weight glycol, and a hydrophilic surfactant having at least one active hydrogen group; and wherein the blocked isocyanate composition is in the form of an organic solvent solution having a solid content of 80%. 0.0 to 15.0
There is provided a water-dispersible blocked isocyanate composition characterized by having an effective NCO content of wt%.

According to the present invention, there is further provided a blocked isocyanate composition comprising an isocyanate group-terminated precursor and a blocking agent for blocking a free isocyanate group of the precursor;
At least an organic diisocyanate, a low molecular weight glycol, and a hydrophilic surfactant having at least one active hydrogen group; A water-dispersible blocked isocyanate composition having a gloss of 60 to 100 under a condition of 60 ° is provided.

According to the present invention, there is further provided an aqueous coating composition comprising at least one of the above-mentioned “water-dispersible block isocyanate composition” and an aqueous resin containing an active hydrogen group; Number of moles of blocked isocyanate groups in the isocyanate composition,
An aqueous coating composition having a ratio of the number of moles of active hydrogen groups in the resin constituting the aqueous resin of 1: 9 to 9: 1 is provided.

According to the present invention, there is further provided an aqueous adhesive composition comprising at least one of the above-mentioned “water-dispersible blocked isocyanate composition” and an aqueous resin containing an active hydrogen group; Aqueous adhesive composition wherein the ratio of the number of moles of blocked isocyanate groups in the reactive blocked isocyanate composition to the number of moles of active hydrogen groups in the resin constituting the aqueous resin is 1: 9 to 9: 1 Things are provided.

The water-dispersible blocked isocyanate of the present invention may further comprise a low molecular weight glycol and, if necessary, a hydrophobic chain having an appropriate chain length, in addition to the conventional technique of introducing a hydrophilic surfactant for improving dispersibility. The organic compound was introduced in a well-balanced manner, and the compatibility with the molecular skeleton of the aqueous polymer solution or aqueous emulsion was improved. Furthermore, by introducing an isocyanurate ring structure having good weather resistance and heat resistance, gloss and sharpness, heat resistance, and weather resistance of the resulting film can be improved.

Claims (8)

[Claims] 1. A blocked isocyanate composition comprising an isocyanate group-terminated precursor and a blocking agent for blocking a free isocyanate group of the precursor; wherein the isocyanate group-terminated precursor is an organic diisocyanate, And at least a hydrophilic surfactant having one or more active hydrogen groups; and the precursor has an isocyanurate ring structure, and the average number of functional groups (f) is 2.0 ≦ f ≦ 4. 2. The content (X) of the low molecular glycol is 0.5 wt% ≦ X ≦
15 wt%, hydrophilic surfactant content (Y) is 0.1 wt% ≦ Y ≦
50% by weight of the water-dispersible blocked isocyanate composition. 2. A blocked isocyanate composition comprising an isocyanate group-terminated precursor and a blocking agent for blocking a free isocyanate group of the precursor, wherein the isocyanate group-terminated precursor is an organic diisocyanate and a low molecular weight glycol. And a hydrophilic surfactant having at least one active hydrogen group and a hydrophobic organic compound having at least one active hydrogen group and having at least 7 carbon atoms; and the precursor isocyanate It has a ring structure, the average number of functional groups (f) is 2.0 ≦ f ≦ 4.2, and the content (X) of the low molecular glycol is 0.5 wt% ≦ X ≦
15 wt%, hydrophilic surfactant content (Y) is 0.1 wt% ≦ Y ≦
50 wt%, hydrophobic organic compound content (Z) is 0 wt% <Z ≦ 30
water-dispersible blocked isocyanate composition, characterized in that the content is wt%. 3. The organic diisocyanate is hexamethylene diisocyanate, and the hydrophilic surfactant having at least one active hydrogen group is poly (oxyethylene) glycol having a degree of polymerization of 3 to 90. A water-dispersible blocked isocyanate composition according to the above. 4. A blocked isocyanate composition comprising an isocyanate group-terminated precursor and a blocking agent that blocks free isocyanate groups of the precursor; wherein the isocyanate group-terminated precursor is an organic diisocyanate, a low molecular weight glycol. And a hydrophilic surfactant having at least one active hydrogen group; and wherein the blocked isocyanate composition is in the form of a 100 to 100,000 mPa.
A water-dispersible blocked isocyanate composition having a viscosity of s / 25 ° C. 5. A blocked isocyanate composition comprising an isocyanate group-terminated precursor and a blocking agent for blocking a free isocyanate group of the precursor, wherein the isocyanate group-terminated precursor comprises an organic diisocyanate and a low molecular weight glycol. And at least a hydrophilic surfactant having at least one active hydrogen group; and 4.0 to 15.0 wt% of the blocked isocyanate composition in a state of a solution of an organic solvent having a solid content of 80%. A water-dispersible blocked isocyanate composition having an effective NCO content of 6. A blocked isocyanate composition comprising an isocyanate group-terminated precursor and a blocking agent for blocking a free isocyanate group of the precursor; wherein the isocyanate group-terminated precursor comprises an organic diisocyanate and a low molecular weight glycol. And at least a hydrophilic surfactant having at least one active hydrogen group; and wherein the blocked isocyanate composition is in the form of a gloss measurement paint at an incident angle of 60 ° and a reflection angle of 60 °. ~ 1
A water-dispersible blocked isocyanate composition having a gloss of 00. 7. An aqueous coating composition comprising at least the water-dispersible blocked isocyanate composition according to claim 1 and an aqueous resin containing an active hydrogen group; said water-dispersible blocked isocyanate The ratio of the number of moles of blocked isocyanate groups in the composition to the number of moles of active hydrogen groups in the resin constituting the aqueous resin is 1:
An aqueous coating composition that is 9 to 9: 1. 8. An aqueous adhesive composition comprising at least the water-dispersible blocked isocyanate composition according to any one of claims 1 to 6 and an aqueous resin containing an active hydrogen group; The ratio between the number of moles of blocked isocyanate groups in the blocked isocyanate composition and the number of moles of active hydrogen groups in the resin constituting the aqueous resin,
An aqueous adhesive composition that is 1: 9 to 9: 1.