JPH06287259A - Production of aqueous dispersed material of crosslinked polyurethane resin particle - Google Patents

Abstract

PURPOSE:To readily obtain an aqueous dispersed material of crosslinked polyurethane resin particles capable of forming a tough film combinedly having high adhesion, resistances to water, heat, solvent and chemicals, etc., at a low cost without limiting kinds of neutralizing agents. CONSTITUTION:The method for producing an aqueous dispersion of crosslinked polyurethane resin particles comprises dispersing a self-water dispersing urethane-based polymer having a polymerizable unsaturated group or a mixture of the urethane-based polymer and other compound having a polymerizable unsaturated group into an aqueous medium and then polymerizing the polymerizable unsaturated group to carry out intra-particle crosslinking of dispersed particles.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing an aqueous dispersion of crosslinked polyurethane resin particles. More specifically, a polymerizable unsaturated group-containing resin composition containing a self-water-dispersible urethane polymer having a polymerizable unsaturated group as an essential component is dispersed in an aqueous medium, and then the unsaturated group is polymerized. The present invention relates to a method for producing an aqueous dispersion of crosslinked polyurethane resin particles, which comprises intraparticle crosslinking of dispersed particles.

The aqueous dispersion of the crosslinked polyurethane resin particles obtained by the present invention is a fine particle having an average particle size of 1 micron (μm) or less, and thus has stable water dispersibility, and A film obtained by coating and drying a resin composition containing an aqueous dispersion is tough and has excellent adhesiveness, water resistance, heat resistance, solvent resistance, chemical resistance, etc., and is used for paints, inks, adhesives, etc. Can be used for the application of the coating composition.

[0003]

2. Description of the Related Art As a method for obtaining an aqueous dispersion of crosslinked polyurethane resin particles, a method of crosslinking water-dispersed resin particles having an isocyanate group at the molecular end with a polyamine is known.

For example, in US Pat. Nos. 3,770,681 and 3,870,684, a linear urethane prepolymer having a cationic ionomer and having a terminal isocyanate group is dispersed in water. 2 sensory
A method of making crosslinked particles with a larger polyamine is disclosed.

Further, in US Pat. Nos. 4,203,883 and 4,408,008, there are disclosed isocyanate-terminated linear prepolymers having a carboxyl group.
Processes for crosslinking with functional chain extenders such as diethylenetriamine are disclosed.

Further, in JP-A-3-128912 and JP-A-4-249517, a water-dispersible urethane prepolymer having an isocyanate group as an end group, a polyisocyanate compound and a polyfunctional amine compound are formed. Aqueous dispersions of crosslinked polyurethanes are disclosed.

However, the above-mentioned method of crosslinking water-dispersed resin particles having an isocyanate group at the molecular end with a polyamine has the following drawbacks.

[0008] One of the problems is that it is necessary to prevent the isocyanate group from being consumed in the step of dispersing a resin having an isocyanate group in water, which limits the method of dispersing in water. For example, in the case of dispersion of a resin having a carboxyl group, it is difficult to carry out unless the neutralizing agent used for ionization contains substantially no active hydrogen such as an inorganic base or triethylamine. Therefore, volatile bases such as ammonia, primary amines, secondary amines, and alkanolamines that are generally used in aqueous coatings cannot be used or are difficult to use.

In addition, in the step of intramolecularly crosslinking the dispersed particles by adding the polyamine to the water-dispersed resin, when a high concentration of polyamine is added, the dispersed particles are bound to each other and the particles are aggregated. It is necessary to add, and as a result, there is a problem that the solid content concentration of the resin dispersion is remarkably reduced.

[0010]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned drawbacks in the method of crosslinking water-dispersed resin particles having an isocyanate group at the molecular end with a polyamine,
At the same time, an object of the present invention is to provide a method for easily obtaining an aqueous dispersion of crosslinked polyurethane resin particles capable of forming a film having higher water resistance and heat resistance at low cost.

[0011]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventor basically found that the crosslinking reaction was not caused by the reaction between an isocyanate group and a polyamine as in the prior art. The inventors have found a method of introducing a polymerizable unsaturated group and polymerizing the same to crosslink it, and completed the present invention.

That is, according to the present invention, a self-water-dispersible urethane polymer having a polymerizable unsaturated group, or a mixture of this and another compound having a polymerizable unsaturated group is dispersed in an aqueous medium, It is intended to provide a method for producing an aqueous dispersion of crosslinked polyurethane resin particles, characterized in that the polymerizable particles are polymerized to cause intraparticle crosslinking of the dispersed particles.

The self-water-dispersible urethane polymer having a polymerizable unsaturated group used in the present invention includes (1) a reaction product of a urethane polymer having a carboxyl group and an unsaturated glycidyl compound, or (2) ) Those obtained by reacting a hydrophilic group-containing urethane prepolymer having an isocyanate group at its end with a compound having an α, β-ethylenically unsaturated bond which can be introduced via the isocyanate group. The amount of the polymerizable unsaturated group introduced is required to be one or more on average in the molecule.

These self-water-dispersible urethane polymers having a polymerizable unsaturated group have a property of forming a stable aqueous dispersion by themselves without using an emulsifier because they have a hydrophilic group in the molecule. I have. The number average molecular weight is 2,000 to 100,000, preferably 3,000.
The range of 0 to 50,000 is suitable.

The reaction of the urethane polymer having a carboxyl group (1) with an unsaturated glycidyl compound is
Generally, it is carried out in a system in which an excess of carboxyl groups exists with respect to glycidyl groups, and one or more unsaturated groups are introduced on average in the molecule, and the acid value of the product is 5 per solid content.
-80, preferably 10-40 remains, which is neutralized with a base so that it can be dispersed in water. The reaction can be carried out without a catalyst, but can be carried out more easily if a catalyst is used. Suitable catalysts include sodium hydroxide, potassium hydroxide, ammonia,
Examples thereof include triethylamine, dimethylbenzylamine, dimethylethanolamine, zirconium octoate, zinc naphthenate and the like.

The urethane polymer having a carboxyl group can be obtained by a known and commonly used method. For example, an organic diisocyanate is reacted with a polyol component in a state where an isocyanate group is in excess, and the urethane prepolymer having an isocyanate group at the terminal thus obtained is a chain extender comprising a low molecular weight compound having two or more active hydrogen atoms. In the method for producing a chain-extendable polyurethane, a compound containing, as at least a part of the polyol component and / or the chain extender, a compound having a carboxyl group which is more reactive with isocyanate than other two or more active hydrogen atoms is used. You can use it.

Specific examples of the above-mentioned organic diisocyanate include ethylene diisocyanate, 1,6-hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate and lysine diisocyanate, if only representative examples are given. Aliphatic diisocyanate, isophorone diisocyanate, hydrogenated 4,
Of alicyclic diisocyanates such as 4'-diphenylmethane diisocyanate, methylcyclohexylene diisocyanate, isopropylidene dicyclohexyl-4,4'-diisocyanate or 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, tolylene diisocyanate Such aromatic diisocyanates and the like can be mentioned.

The above-mentioned polyol components which are generally used or can be used in the production of polyurethanes can be applied here. Particularly representative examples are polyester polyols such as dicarboxylic acids (adipic acid, azelaic acid, sebacic acid, succinic acid, glutaric acid, maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, etc.). And glycol (ethylene glycol, propylene glycol, 1,4-butanediol, 1,3-butanediol, 1,6-hexanediol, 1,8-octamethylenediol, neopentyl glycol, bishydroxymethylcyclohexane, bishydroxyethylbenzene , An alkyl dialkanol amine, etc.), such as polyethylene adipate, polybutylene adipate, polyhexamethylene adipate, polyethylene / propylene adipate; ring-opening polymerization of lactones. Polylactone diols such as polycaprolactone diol,
Polyvalerolactone diol and the like and polyether polyols, such as alkylene oxides of low molecular weight glycols (ethylene glycol, propylene glycol, 1,4-butane diol, etc.) (C2-C4 alkylene oxides such as ethylene oxide, propylene oxide and butylene oxide). Etc.) and ring-opening polymerization products of the above alkylene oxides, specifically polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, and mixtures of two or more thereof.

Further, only specific examples of the above-mentioned active hydrogen atom-containing low molecular weight compound used as a chain extender are exemplified, and ethylene glycol, propylene glycol, 1,4-butanediol, 1, Low molecular weight glycols such as 6-hexanediol and aliphatic diamines such as ethylenediamine, propylenediamine, butylenediamine, hexamethenediamine, 2,2,4-trimethylhexamethylenediamine and isophoronediamine, dicyclohexylmethane-4,4'- Examples include diamines, isopropylidenedicyclohexyl-4,4'-diamines, and alicyclic diamines such as 1,4-diaminocyclohexane.

Further, only the compounds which are particularly representative as the compounds having a carboxyl group which is more reactive with isocyanate than the other two or more active hydrogen atoms are exemplified, and diaminocarboxylic acids are given. For example ricin,
Cystine and 3,5-diaminocarboxylic acid, 2,5-
Diaminohexanoic acid, 2,6-dihydroxybenzoic acid and especially dihydroxyalkanoic acid such as 2,2-dihydroxypropionic acid and a carboxyl group-containing polycaprolactone diol obtained by the reaction of 2,2-dihydroxypropionic acid with ε-caprolactone Can be mentioned.

Examples of the unsaturated glycidyl compound used in the above (1) include allyl glycidyl ether and glycidyl (meth) acrylate.

The above-mentioned urethane-based polymer having a carboxyl group and its reaction with an unsaturated glycidyl compound may be carried out in a solventless system, but a solvent is usually used. Examples of the solvent used include alcohols such as ethanol, isopropanol and n-butyl alcohol; ketones such as acetone, methyl ethyl ketone and cyclohexanone; ethers such as dioxane and tetrahydrofuran; aromatic hydrocarbons such as toluene; dimethylformamide and dimethyl. Examples thereof include amides such as acetamide; halogenated hydrocarbons such as chlorobenzene, trichlene, and percene; esters such as ethyl acetate and butyl acetate, and mixtures of two or more thereof. From the viewpoint of solubility and economy, isopropanol, n and the like are preferable.
-Butyl alcohol, acetone, methyl ethyl ketone,
Ethyl acetate, toluene and mixtures of two or more of these. A solvent having active hydrogen such as alcohols is used at a stage where substantially no reaction with isocyanate occurs except when it acts as a chain terminator.

On the other hand, a compound having an α, β-ethylenically unsaturated bond which can be introduced via the isocyanate group is added to the hydrophilic group-containing urethane prepolymer having an isocyanate group at the terminal of the above (2) and reacted. More specifically, the items are as follows.

That is, the above-mentioned hydrophilic group-containing urethane prepolymer having an isocyanate group at the terminal generally has an excess amount of organic diisocyanate and a polyol component, and a hydrophilic group-containing urethane prepolymer having a reactivity with isocyanate at the terminal. It can be obtained by a reaction with a compound having two functional groups. Here, the same organic diisocyanate and polyol components as those described in (1) above can be used.

On the other hand, as the compound having the hydrophilic group and two functional groups reactive with isocyanate at the end, the hydrophilic group includes a polyether group, a phosphoric acid ester group, a sulfonic acid group, and Primary amino group, carboxyl group,
Alternatively, diols and diamines having any of their neutralizing bases are suitable. To give only representative examples as specific examples, polyoxyethylene glycol,
Polyoxyethylene diaminopropyl ether, trimethylolpropane monophosphate ester, trimethylolpropane monosulfate ester, polyester diol in which at least part of the dibasic acid component is sodium sulfosuccinic acid, or sodium sulfoisophthalic acid, N-methyldiethanolamine, Diaminocarboxylic acids such as lysine, cystine and 3,5-diaminocarboxylic acid,
2,6-dihydroxybenzoic acid and especially dihydroxyalkanoic acids such as 2,2-dihydroxypropionic acid and carboxyl-containing polycaprolactone diols obtained by the reaction of 2,2-dihydroxypropionic acid with ε-caprolactone.

A necessary amount of one or more of these hydrophilic groups is introduced into the urethane prepolymer molecule, and the required amount is determined by the kind and combination of hydrophilic groups. Among the above exemplified, particularly preferable as the hydrophilic group is a carboxyl group, a sulfonate group and a polyoxyethylene chain in the molecule, or one or two or three thereof are combined, or It is a mixture of those having a carboxylic acid group, and in particular, introduction of a carboxyl group is easy to balance in various respects and easy to operate.
In this case, the acid value of the solid content is 10 to 80, preferably 15 to
40.

As a typical example of the compound having an α, β-ethylenically unsaturated bond which can be introduced through the isocyanate group, an active hydrogen group-containing unsaturated compound is first mentioned. As a specific example, hydroxyalkyl (meth) such as hydroxyethyl (meth) acrylate and hydroxypropyl (meth) acrylate
Acrylate, polyoxyethylene (meth) acrylate, polyoxyalkylene (meth) acrylate such as polyoxypropylene (meth) acrylate, glycerin mono and di (meth) acrylate, trimethylolpropane mono and di (meth) acrylate, pentaerythritol di And tri (meth) acrylate, allyl alcohol, (meth) acrylamide, N-methylol (meth) acrylamide, maleic acid amide and the like.
Also, α having one or two isocyanate groups,
A compound having a β-ethylenically unsaturated bond can also be introduced. To introduce these, a chain extender such as a diol or diamine as described above is further added to the mixed system with the urethane prepolymer. You can Examples of the compound having an α, β-ethylenically unsaturated bond having an isocyanate group include half urethane compounds of the above-mentioned active hydrogen group-containing unsaturated compound and the above organic diisocyanate compound and m-isopropenyl-α, α dimethylbenzyl isocyanate. Mention may be made of vinyl isocyanates such as 2-methyl-2-isocyanatopropyl methacrylate.

The hydrophilic group-containing urethane prepolymer in which the compound having an α, β-ethylenically unsaturated bond is introduced may be further chain-extended by utilizing the remaining isocyanate group, if necessary. Examples of the chain extender used include the same as those used in (1) above, but diamines are preferable among them.

In the present invention, in addition to the self-water-dispersible urethane-based polymer, it does not necessarily have self-water-dispersibility, but it can be water-dispersed by blending with the self-water-dispersible urethane-based polymer. Other compounds having a polymerizable unsaturated group can be used in combination. The mixing ratio of the other compound having a polymerizable unsaturated group is 50% or less, preferably 20% or less.

Examples of such compounds include usual monomers, oligomers and ethylenically unsaturated group-containing polymers having a radically polymerizable unsaturated bond, and specific examples include the following.

Examples of the monomer include esterified products of acrylic acid or methacrylic acid and a monohydric alcohol having 1 to 25 carbon atoms, such as methyl (meth) acrylate, ethyl (meth) acrylate, ( N-butyl (meth) acrylate, iso-butyl (meth) acrylate,
Tert-butyl (meth) acrylate, propyl (meth) acrylate, hexyl (meth) acrylate, (meth)
Octyl acrylate, lauryl (meth) acrylate,
2-Ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, stearyl (meth) acrylate and the like are included.

As the monomer, vinyl aromatic compounds such as styrene, vinyltoluene, methylstyrene, chlorostyrene and divinylbenzene; vinyl acetate, vinyl chloride, vinyl isobutyl ether, methyl vinyl ether, acrylonitrile, 2-ethylhexyl vinyl ether, etc. The vinyl compounds of can also be used.

Examples of the oligomer include diethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, 1,3-butanediol di (meth) acrylate, 1,4-butanediol. Di (meth) acrylate, neopentyl glycol di (meth)
Di, tree or tetravinyl compounds such as acrylate, 1,6-hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate and the like are included. To be done.

The above-mentioned monomers and oligomers can be used alone or in admixture of two or more.

Examples of the ethylenically unsaturated group-containing polymer include a resin obtained by condensing (meth) acrylic acid with polyester, an ethylenically unsaturated group-containing polyurethane resin, an ethylenically unsaturated group-containing epoxy resin, and an ethylenically unsaturated group. Examples thereof include saturated group-containing phosphorus epoxy resin, ethylenically unsaturated group-containing acrylic resin, and ethylenically unsaturated group-containing melamine resin.

When a self-water-dispersible urethane polymer introduced with a compound having an α, β-ethylenically unsaturated bond via the isocyanate group of the above (2) is used, the polymerizable unsaturated group is One of the preferred embodiments for obtaining a blend with other compounds having is to blend the above-mentioned hydrophilic group-containing urethane prepolymer with a hydrophobic polyisocyanate having an average isocyanate functionality of 2.1 or more, and to add the isocyanate group to the isocyanate group. A compound having an α, β-ethylenically unsaturated bond which can be introduced via a compound is added and reacted.

The average isocyanate functionality described above is 2.1.
The above hydrophobic polyisocyanates include hexamethylene diisocyanate, isophorone diisocyanate and a trimer of 2,4-toluene diisosonate, burette-modified hexamethylene diisocyanate, 2,4
-Toluene diisosonate and trimethylolpropane adducts, m- or p-tetramethylxylene diisocyanate and trimethylolpropane adducts, and mixtures of diphenylmethane diisocyanate and polymethylene polyphenyl polyisocyanates.

In the present invention, the self-water-dispersible urethane polymer having a polymerizable unsaturated group, or a mixture thereof with another compound having a polymerizable unsaturated group, is usually dissolved in an organic solvent. In order to disperse this in an aqueous medium, known and conventional methods can be applied.

For example, when the resin contains a carboxyl group as a hydrophilic group, it is dispersed in water together with a base for neutralizing a part or all of the hydrophilic group. Alternatively, the resin solution may be gradually added with stirring to disperse the resin solution, or conversely, water containing a base may be gradually added to the resin solution to perform phase inversion emulsification. .

Generally, a method of gradually instilling water containing a base while stirring the resin solution to effect phase inversion emulsification is to obtain a stable resin dispersion having a fine particle size. It is more preferable because it is easy to obtain.

The basic substance which can be applied to neutralize and ionize the carboxyl group in the resin includes lithium hydroxide, potassium hydroxide, sodium hydroxide, ammonia and various amines. Examples of amines include primary, secondary or tertiary alkylamines, and representative examples include methylamine, ethylamine, propylamine, butylamine, amylamine, dimethylamine, diethylamine, dipropylamine, diamine. Butylamine, trimethylamine, triethylamine, tripropylamine, morpholine; primary, secondary or tertiary
Grade alkanolamines, typical examples of which include monoethanolamine, diethanolamine, dimethylethanolamine and diethylethanolamine.
Among these bases, good dispersibility, and highly volatile ammonia, diethylamine, which does not easily remain in the coating film,
Triethylamine and dimethylethanolamine are preferred. The above bases may be used alone or in combination of two or more. The amount of base used is generally 0.1 to 2.0 equivalents, preferably 0.3 to 1.2 equivalents, relative to the carboxyl groups in the resin.

The aqueous dispersion thus obtained can be used as it is for the next step of polymerization of the polymerizable unsaturated group, but in order to carry out the polymerization more smoothly, it is preferably in the dispersion. It is suitable to remove some or all of the organic solvent contained. A method using a membrane can be considered for removing the organic solvent, but it can be easily carried out by distillation under normal pressure or reduced pressure, and preferably, it does not impair the stability of the dispersion system. Is appropriate.

In the present invention, the polymerization of the polymerizable unsaturated group for intra-particle crosslinking of the resin particles dispersed in water is carried out by heating at 40 to 100 ° C. with a polymerization initiator and stirring for 10 minutes to 5 hours. Can be done easily by.

As the polymerization initiator which can be used, only representative ones are exemplified. Benzoyl peroxide, lauroyl peroxide, tert-butyl peroxyoctoate, tert-butyl peroxyacetate,
Organic peroxide-based initiators such as tert-butyl peroxybenzoate, nitrile-based initiators such as azobisisobutyronitrile or azobisisovaleronitrile, and other known organic radical polymerization initiators can be used. When a phase initiator is used, it is preferable to add it to the resin solution in advance before dispersing it in water.

On the other hand, examples of the initiator which can be used in the aqueous dispersion of the polymerizable unsaturated group-containing resin include potassium persulfate, ammonium persulfate, or azobisbutyronitrile or its hydrochloride. Furthermore, if necessary, an organic peroxide such as cumene hydroperoxide or tert-butyl hydroperoxide may also be added.
Can be used. Furthermore, these persulfates and peroxides, metal ions such as iron ions, or sodium sulfoxylate formaldehyde,
A so-called redox type initiator which is used in combination with a reducing agent such as sodium pyrosulfite or L-ascorbic acid can also be used.

The amount of the polymerization initiator used may be appropriately selected from the range of 0.5 to 50 mmol per equivalent of the unsaturated group.

As a method for confirming the polymerization of unsaturated groups,
It is preferable to measure the bromine number, but as a simple method, it can be judged by applying the obtained water dispersion to a plastic film or the like and observing the change in tackiness before and after the polymerization.

Further, the crosslinking of the dispersed particles can be easily confirmed by the fact that the particles become insoluble in a solvent such as tetrahydrofuran.

[0049]

EXAMPLES Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited thereto. In the following, all parts and% are based on weight unless otherwise specified.

Example 1 PLACCEL was placed in a 2 liter round bottom flask equipped with a stirrer, thermometer, condenser and nitrogen gas inlet tube.
205A (manufactured by Daicel Chemical Industries, Ltd., carboxyl group-containing polycaprolactone diol, hydroxyl value 220 mgK
OH / g, acid value 110 mgKOH / g) 162.5g, PLAC
119.5 g of CEL 220AH (manufactured by the same company, polycaprolactone diol, hydroxyl value 220 mgKOH / g), 150.0 g of isophorone diisocyanate (IPDI) and 108.0 g of methyl ethyl ketone (MEK) were charged. The mixture system was stirred and heated to 80 ° C. 8
After a lapse of time, when the decrease of NCO group was not observed,
180 g of MEK was added and diluted, and the temperature was adjusted to 60 ° C. Then 44.5 of isophorone diamine (IPDA)
and isopropyl alcohol (IPA) 195.5 g
Was added and stirring was continued at 60 ° C. for 2 hours to obtain a urethane-based polymer solution having a carboxyl group. This product was confirmed by infrared absorption spectrum to have no NCO group remaining. Nonvolatile matter 49.8%, acid value 36.
It was 5 mg KOH / g.

20% of glycidyl methacrylate is added here.
After adding 0 g and mixing, 5.4 g of 28% ammonia water
Was added, the mixture was heated to the reflux temperature (78 to 80 ° C.), and stirring was continued for 5 hours. Nonvolatile matter 45.8
%, The acid value was 20.5 mg KOH / g per solid content. This is designated as self-water-dispersible urethane polymer A-1 having a polymerizable unsaturated group.

Subsequently, 218 parts of A-1 above, 0.2 part of benzoyl peroxide and 54 parts of MEK were mixed, and 278 parts of ion-exchanged water and 1.3 parts of 28% ammonia water were mixed therein. It was gradually added with stirring to obtain a translucent emulsion of A-1.

Next, this emulsion was distilled under reduced pressure at a temperature of 50 ° C. or lower to remove the solvent.

A sample was taken at this point, and when this was added to a large amount of tetrahydrofuran (THF), it was completely dissolved. Also, a film obtained by applying this sample to a polyester film with drawdown rod # 7 and drying at room temperature showed tackiness.

Subsequently, the emulsified liquid of A-1 from which the solvent was removed was stirred at 80 ° C. for 1 hour and then sampled again. When it was added to THF in the same manner as above, it did not dissolve and the liquid showed turbidity. In addition, the coating applied to the polyester film in the same manner as above was not tacky, and no peeling was observed at all in the adhesiveness test using the cellophane tape, indicating that the film was firmly bonded.

After continuing stirring at 80 ° C. for another hour,
Distillation under reduced pressure again gave an aqueous dispersion of crosslinked polyurethane resin particles having a nonvolatile content of 32.4%.

Example 2 218 parts of the self-water-dispersible urethane polymer A-1 having a polymerizable unsaturated group obtained in Example 1, Bremmer A
1 part of TT (Nippon Oil & Fats Co., Ltd., trimethylolpropane triacrylate), 0.2 part of azobisisobutyronitrile and 54 parts of MEK were mixed, and 278 parts and 28% of ion-exchanged water were mixed therein. 1.3 parts of ammonia water was gradually added with stirring to obtain a translucent emulsion.

Next, this emulsion was distilled under reduced pressure at a temperature of 50 ° C. or lower to remove the solvent.

A sample was taken at this point, and when it was added to a large amount of tetrahydrofuran (THF), it was completely dissolved. Also, a film obtained by applying this sample to a polyester film with drawdown rod # 7 and drying at room temperature showed tackiness.

Subsequently, the emulsion from which the solvent was removed was stirred at 80 ° C. for 1 hour and then sampled again. When it was added to THF in the same manner as above, it did not dissolve and the liquid showed turbidity. In addition, the film applied to the polyester film in the same manner as above is not tacky,
No peeling was observed in the adhesion test using cellophane tape, indicating that the films were firmly bonded.

After continuing stirring at 80 ° C. for another hour,
It was again distilled under reduced pressure to obtain an aqueous dispersion of crosslinked polyurethane resin particles having a nonvolatile content of 33.2%.

Example 3 PLACCEL was placed in a 1 liter round bottom flask equipped with a stirrer, thermometer, condenser and nitrogen gas inlet tube.
186.9 g of 212 (manufactured by Daicel Chemical Industries, Ltd., polycaprolactone diol, hydroxyl value 90 mgKOH / g)
(0.3 equivalents) and 100.0 g (0.9 equivalents) of IPDI were charged. The mixture system was stirred and heated to 110 ° C. After 1 hour, the mixture was cooled to 80 ° C., 20.1 g (0.3 equivalent) of dimethylolpropionic acid, 0.3 g of dibutyltin dilaurate and 79.7 g of ethyl acetate were added, and the mixture was reacted at 80 ° C. for 2 hours. , 11.7 g (0.1 equivalent) of hydroxyethyl acrylate was added, the reaction was continued at the same temperature for 3 hours, and then the temperature was cooled to 60 ° C. At this time, the NCO group content was 2.6% in terms of solid content. MEK 246.7g and propylenediamine 7.4g (0.2 equivalent) were added here, and stirring was continued at the same temperature for 1 hour. This product was confirmed by infrared absorption spectrum to have almost no remaining NCO group. Nonvolatile content 40.1
%, The acid value was 25.4 mgKOH / g per solid content. This is designated as self-water-dispersible urethane polymer B-1 having a polymerizable unsaturated group.

Subsequently, 250 parts of B-1 and 0.15 part of benzoyl peroxide were mixed and dissolved, and 300 parts of ion-exchanged water and 3.3 parts of 28% ammonia water were gradually added thereto with stirring. In addition, a semi-transparent emulsion of B-1 was obtained.

Next, this emulsion was distilled under reduced pressure at a temperature of 50 ° C. or lower to remove the solvent.

A sample was taken at this point, and when it was added to a large amount of tetrahydrofuran (THF), it was completely dissolved. Also, a film obtained by applying this sample to a polyester film with drawdown rod # 7 and drying at room temperature showed tackiness.

Subsequently, the emulsified liquid of B-1 from which the above solvent was removed was stirred at 80 ° C. for 1 hour and then sampled again. When it was added to THF in the same manner as above, it did not dissolve and the liquid showed turbidity. In addition, the coating applied to the polyester film in the same manner as above was not tacky, and no peeling was observed at all in the adhesiveness test using the cellophane tape, indicating that the film was firmly bonded.

After continuing stirring at 80 ° C. for another hour,
It was again distilled under reduced pressure to obtain an aqueous dispersion of crosslinked polyurethane resin particles having a nonvolatile content of 33.5%.

Example 4 250 parts of the self-water-dispersible urethane polymer B-1 having a polymerizable unsaturated group obtained in Example 3 was mixed with 4 parts of 1,4-butanediol diacrylate. 300 parts of ion-exchanged water and 3.3% of 28% ammonia water
Parts were gradually added with stirring to obtain a translucent emulsion.

Next, this emulsion was distilled under reduced pressure at a temperature of 50 ° C. or lower to remove the solvent.

A sample was taken at this point, and when this was added to a large amount of tetrahydrofuran (THF), it was completely dissolved. Also, a film obtained by applying this sample to a polyester film with drawdown rod # 7 and drying at room temperature showed tackiness.

Subsequently, 0.2 part of ammonium persulfate was added to the emulsion from which the solvent had been removed, and the mixture was stirred at 80 ° C. for 1 hour and then sampled again. TH same as above
When it was added to F, it did not dissolve and the liquid showed turbidity. In addition, the coating applied to the polyester film in the same manner as above was not tacky, and no peeling was observed at all in the adhesiveness test using the cellophane tape, indicating that the film was firmly bonded.

After continuing stirring at 80 ° C. for another hour,
Distillation under reduced pressure again gave an aqueous dispersion of crosslinked polyurethane resin particles having a nonvolatile content of 33.6%.

Example 5 PLACCEL was placed in a 2 liter round bottom flask equipped with a stirrer, thermometer, condenser and nitrogen gas inlet tube.
205.6 g of 212 (manufactured by Daicel Chemical Industries, Ltd., polycaprolactone diol, hydroxyl value 90 mgKOH / g)
(0.33 equivalent) and 100.0 g (0.9 equivalent) of IPDI were charged. The mixture system was stirred and heated to 110 ° C. After 1 hour, it was cooled to 80 ° C., 16.1 g (0.24 equivalent) of dimethylolpropionic acid, Bremmer G
LM (trade name of glycerol monomethacrylate, manufactured by NOF CORPORATION), 14.4 g (0.18 equivalent), 0.3 g of dibutyltin dilaurate and 84.
After adding 0 g and reacting at 80 ° C. for 4 hours, the temperature was adjusted to 60
Cooled to ° C. At this time, the NCO group content was 1.9% in terms of solid content. 698 g of MEK, 30 g of isopropyl alcohol and 5.2 g (0.09 equivalent) of hexamethylenediamine were added thereto, and stirring was continued at the same temperature for 1 hour. This product was confirmed by infrared absorption spectrum to have almost no remaining NCO group. Nonvolatile content 30%,
The acid value was 19.5 mg KOH / g per solid content. This is referred to as a self-water-dispersible urethane polymer B-2 having a polymerizable unsaturated group.

Subsequently, 333 parts of the above-mentioned B-2 and 0.15 part of benzoyl peroxide were mixed and dissolved, and 300 parts of ion-exchanged water and 2.5 parts of 28% ammonia water were gradually stirred therein with stirring. In addition, a semi-transparent emulsion of B-2 was obtained.

Next, this emulsion was distilled under reduced pressure at a temperature of 50 ° C. or lower to remove the solvent.

A sample was taken at this point, and when this was added to a large amount of tetrahydrofuran (THF), it was completely dissolved. Also, a film obtained by applying this sample to a polyester film with drawdown rod # 7 and drying at room temperature showed tackiness.

Subsequently, the emulsified liquid of B-2 from which the above solvent was removed was stirred at 80 ° C. for 1 hour and then sampled again. When it was added to THF in the same manner as above, it did not dissolve and the liquid showed turbidity. In addition, the coating applied to the polyester film in the same manner as above was not tacky, and no peeling was observed at all in the adhesiveness test using the cellophane tape, indicating that the film was firmly bonded.

After continuing stirring at 80 ° C. for another hour,
Distillation under reduced pressure again gave an aqueous dispersion of crosslinked polyurethane resin particles having a nonvolatile content of 36.5%.

Example 6 A 5-liter round-bottomed flask equipped with a stirrer, a thermometer, a condenser and a nitrogen gas introduction tube was charged with Clapol P-2010 (manufactured by Kuraray Co., Ltd., poly MPD adipate diol, hydroxyl value 56 mgKOH / g). ) Of 1,000.0 g
(1.0 equivalent), hexamethylene diisocyanate (H
252.3 g (3.0 equivalents) of DI) was charged. The mixture system was stirred and heated to 110 ° C. One hour later 80
Cooled to ℃, 67.1g of dimethylolpropionic acid
(1.0 equivalent), 1.3 g of dibutyltin dilaurate and 329.8 g of ethyl acetate were added, and the mixture was reacted at 80 ° C. for 2 hours. At this time, the NCO group content was 3.2% in terms of solid content. 46 g of ethyl acetate, Bernock DN-950S (Dainippon Ink and Chemicals, Inc.)
Manufactured by HDI burette) and N-methylolacrylamide (118 g) were added, and the reaction was continued at a temperature of 80 ° C. for 3 hours. Here, 4.7g of BPO and MEK
1,880 g of was added. The nonvolatile content was 40% and the acid value was 18.5 mgKOH / g per solid content.

In a separate container, 4,500 g of ion-exchanged water and 34 g of 28% ammonia water were prepared, and the above resin solution was gradually added with stirring to obtain a milky white aqueous dispersion.

Next, this dispersion was transferred to an evaporator and distilled under reduced pressure at a temperature of 50 ° C. or lower to remove the solvent.

A sample was taken at this point, and when this was added to a large amount of tetrahydrofuran (THF), it was completely dissolved. Also, a film obtained by applying this sample to a polyester film with drawdown rod # 7 and drying at room temperature showed tackiness.

Subsequently, the above dispersion liquid from which the solvent had been removed was stirred at 80 ° C. for 1 hour under stirring and then sampled again. When it was added to THF in the same manner as above, it did not dissolve and the liquid showed turbidity. In addition, the film applied to the polyester film in the same manner as above is not tacky,
No peeling was observed in the adhesion test using cellophane tape, indicating that the films were firmly bonded.

After continuing stirring at 80 ° C. for a further 1 hour,
Distillation under reduced pressure again gave an aqueous dispersion of crosslinked polyurethane resin particles having a nonvolatile content of 35.6%.

[0085]

INDUSTRIAL APPLICABILITY The aqueous dispersion of crosslinked polyurethane resin particles according to the present invention crosslinks water-dispersed resin particles having a conventionally known isocyanate group at the molecular end with a polyamine as a neutralizing agent necessary for water dispersion. A base having an active hydrogen, such as ammonia, which is difficult to use in the method, can be easily used. Moreover, since mutual bonding between particles is unlikely to occur at the stage of crosslinking the dispersed resin particles, an aqueous dispersion of finely crosslinked particles can be easily and stably produced.

By coating and drying the aqueous dispersion of the crosslinked polyurethane resin particles obtained in the present invention on various substrates, a tough film which is flexible and has no tackiness can be obtained, and the adhesiveness, water resistance and heat resistance can be obtained. Since it has excellent properties, solvent resistance, chemical resistance, etc., it can be used for applications such as paints, inks, adhesives, and other coating compositions.

Claims (5)

[Claims] 1. A self-water-dispersible urethane polymer having a polymerizable unsaturated group, or a mixture of the self-water-dispersible urethane polymer or another compound having a polymerizable unsaturated group is dispersed in an aqueous medium, and then the polymerizable unsaturated group is dispersed. A method for producing an aqueous dispersion of crosslinked polyurethane resin particles, characterized in that intramolecular crosslinking of dispersed particles is carried out by polymerizing a saturated group. 2. The crosslink according to claim 1, wherein the self-water-dispersible urethane polymer having a polymerizable unsaturated group is a reaction product of a urethane polymer having a carboxyl group and an unsaturated glycidyl compound. A method for producing an aqueous dispersion of polyurethane resin particles. 3. A hydrophilic group-containing urethane prepolymer having an isocyanate group at the terminal, or a mixture thereof with a hydrophobic polyisocyanate having an average isocyanate functionality of 2.1 or more can be introduced via the isocyanate group. A compound having a different α, β-ethylenically unsaturated bond is added and reacted, and then dispersed in an aqueous medium, and then the α, β-ethylenically unsaturated bond is polymerized. A method for producing an aqueous dispersion. 4. A hydrophilic group-containing urethane prepolymer having an isocyanate group at the terminal or a mixture of the urethane prepolymer and a hydrophobic polyisocyanate having an average isocyanate functionality of 2.1 or more can be introduced through the isocyanate group. A compound having an α, β-ethylenically unsaturated bond is added and reacted, and another compound having at least one α, β-ethylenically unsaturated bond is further mixed therein, and then dispersed in an aqueous medium, and then A method for producing an aqueous dispersion of crosslinked polyurethane resin particles, which comprises polymerizing the α, β-ethylenically unsaturated bond. 5. The hydrophilic group-containing urethane prepolymer having an isocyanate group at the terminal has at least one selected from a carboxyl group, a sulfonate group and a polyoxyethylene chain as a hydrophilic group. The method for producing an aqueous dispersion of crosslinked polyurethane resin particles according to item 4.