JPH07102037A - Method for producing water-soluble active energy ray curable resin - Google Patents

Abstract

(57) [Summary] [Object] To provide a water-soluble active energy ray-curable resin useful in various fields of application such as coating agents and printing inks. [Structure] Polyurethane resin obtained by reacting polyhydroxy compound, radical-polymerizable unsaturated group-containing polyhydroxy compound, anionic hydrophilic group-containing polyhydroxy compound, polyisocyanate compound and radical-polymerizable unsaturated group-containing monohydroxy compound A method for producing a water-soluble active energy ray-curable resin, which comprises neutralizing the anionic hydrophilic group of 1. with a tertiary amine.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel and useful method for producing a water-soluble active energy ray curable resin.
More specifically, the water-soluble active energy ray-curable resin of the present invention can be arbitrarily diluted with water and is suitable for a wide range of applications such as coating agents, printing inks, photoresists, adhesives and plate-making materials. It is an extremely useful resin that can be cured by so-called active energy rays such as electron beams and ultraviolet rays.

[0002]

2. Description of the Related Art In order to reduce environmental pollution and improve working environment, there is a strong demand for water-based coating agents, printing inks, and other fields of application. It has begun. However, an active energy ray curable resin that has been made water-based, which is energy-saving without degrading the performance, has not been found in each application field. In particular, there are many food packaging films and coating agents for beverage cans that require hot water resistance in the retort process, but at present the requirements are not met. In addition, for photoresists and plate-making materials, there is a strong demand for water-soluble types that do not contain organic solvents, from the viewpoint of safety in image processing, waste liquid processing, and various operations, but the water-soluble types that satisfy There is almost no active energy ray curable resin.

[0003]

In view of the above-mentioned situation, the inventors of the present invention can be used for applications that cannot be satisfied with existing water-based resins, and furthermore, the hot water resistance, curability and Excellent in cross-linking, water-solubilized,
The present invention has been completed by earnestly studying the active energy ray curable resin.

[0004]

Means for Solving the Problems That is, the present invention provides a polyhydroxy compound, a radical-polymerizable unsaturated group-containing polyhydroxy compound, an anionic hydrophilic group-containing polyhydroxy compound, a polyisocyanate compound and a radical-polymerizable unsaturated group. The present invention relates to a method for producing a water-soluble active energy ray-curable resin, which comprises neutralizing an anionic hydrophilic group of a polyurethane resin obtained by reacting a contained monohydroxy compound with a tertiary amine.

The water-soluble active energy ray-curable polyurethane resin of the present invention has the following characteristics as compared with the conventionally known water-based active energy ray-curable polyurethane resin.
That is, in the present invention, when introducing a radically polymerizable unsaturated group, using a radically polymerizable unsaturated group-containing polyhydroxy compound and a radically polymerizable unsaturated group-containing monohydroxy compound, the molecular side chain of the polyurethane resin and the molecular terminal By introducing radically polymerizable unsaturated groups into both of them, it is easy to control the crosslink density of the cured film, and the hot water resistance and curability required for the film are dramatically improved. A polyurethane resin is provided.

Examples of the polyhydroxy compound used in the present invention include known polyhydroxy compounds generally used for producing polyurethane resins. For example, ethylene glycol, 1,2 or 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, neopentyl glycol, cyclohexanedimethanol, diethylene glycol, triethylene glycol. , Dipropylene glycol, glycerol, trimethylolpropane, trimethylolpropane, pentaerythritol,
Polyethylene glycol, polypropylene glycol,
Examples thereof include polytetramethylene glycol, polyester polyol, polycaprolactone polyol, polyvalerolactone polyol, and polycarbonate polyol, and these may be used alone or in combination of two or more kinds.

The radical-polymerizable unsaturated group-containing polyhydroxy compound used in the present invention is used for introducing a radical-polymerizable unsaturated group into a side chain of a molecule of a polyurethane resin. A compound having one or more radically polymerizable unsaturated groups and two or more hydroxyl groups in combination, and examples thereof include compounds such as glycerol monoacrylate, glycerol monomethacrylate, and glycerol monoarylate. Further, the radical-polymerizable unsaturated group-containing polyhydroxy compound is a compound having one secondary amino group and two hydroxyl groups in the molecule such as diethanolamine or 2-hydroxymethylaminoethanol, and isolophone diisocyanate is added to the secondary amino group. It can also be obtained by reacting the isocyanate group of a compound having both an isocyanate group and a radical polymerizable unsaturated group in the molecule such as a 1: 1 mol addition compound of 2-hydroxyethyl acrylate. In addition, ethylene glycol diglycidyl ether diacrylate ester,
Compounds such as diethylene glycol diglycidyl ether diacrylate, ethylene glycol diglycidyl ether dimethacrylate, 1,6-hexanediol diglycidyl ether diacrylate, and propylene glycol diglycidyl ether diacrylate are not radically polymerizable. The saturated group and the hydroxyl group are bifunctional and can be used. These radical-polymerizable unsaturated group-containing polyhydroxy compounds listed above may be used alone or in combination of two or more.

The anionic hydrophilic group-containing polyhydroxy compound used in the present invention is used for introducing an anionic hydrophilic group into a polyurethane resin, and, for example, 2,2-dimethylolpropionic acid, 2,2-Dimethylolacetic acid, 2,2-dimethylolpentanoic acid, or a half-ester compound obtained by the reaction of a triol compound and an acid anhydride compound, sodium dimethylsulfoisophthalate and glycols under conditions of excess glycols The sulfonate diol compound and the like obtained by the transesterification reaction may be mentioned, and these may be used alone or in combination of two or more kinds.

Examples of the polyisocyanate compound used in the present invention include 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane- 4,4'-diisocyanate, norbornane diisocyanatomethyl, tolylene diisocyanate, diphenylmethane-4,4'-diisocyanate,
Examples include xylylene diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, α, α, α ′, α′-tetramethylxylylene diisocyanate,
You may use these individually or in combination of 2 or more types.

The radical-polymerizable unsaturated group-containing monohydroxy compound used in the present invention is used to introduce a radical-polymerizable unsaturated group at the molecular end of the polyurethane resin. There are saturated monohydroxy compounds, such as 2-hydroxyethyl (meth)
Acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate,
3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, allyl cellosolve, N-methylol acrylamide, pentaerythritol tri (meth) acrylate, dipentaerythritol monohydroxypentaacrylate, stearic acid modified pentaerythritol diacrylate, Ethylene oxide Propylene oxide-modified phthalic acid monomethacrylate, tris (2-hydroxyethyl) isocyanurate di (meth) acrylate, glycerol di (meth)
Acrylate, glycerol methacrylate acrylate, glycerol (meth) acrylate alkylate,
Glycerol (meth) acrylate alkenylate, bis (acryloxyethyl) monohydroxyethyl isocyanurate, and the like.

Further, for example, by adding (meth) acrylic acid and a monoepoxy compound, or
A compound having both an active hydrogen atom and a radically polymerizable unsaturated group can also be obtained by ring-opening polymerization of an epoxy monomer using (meth) acrylic acid as a starting species. Examples of the monoepoxy compound include methyl glycidyl ether, butyl glycidyl ether, allyl glycidyl ether, 2-ethylhexyl glycidyl ether, phenyl glycidyl ether, and glycidyl ester of versatic acid 10 (Shell Chemical Co., Ltd., Cardura E10). Examples thereof include ethylene oxide, propylene oxide and butylene oxide. As an example of a ring-opening polymer of an epoxy monomer, polyoxyethylene glycol (n = 2 to
9) Mono (meth) acrylate, polyoxypropylene glycol (n = 5 to 12) mono (meth) acrylate, polyoxyethylene glycol (n = 7) polyoxypropylene glycol (m = 3) monomethacrylate, polyoxyethylene Glycol (n = 10) Polyoxytetramethylene glycol (m = 5) Monomethacrylate, polyoxypropylene glycol (n = 15)
~ 18) polyoxytetramethylene glycol (m = 5
~ 8) Monomethacrylate etc. can be mentioned.

Further, a compound having both a hydroxyl group and a radically polymerizable unsaturated group by ring-opening polymerization of a lactone monomer such as ε-caprolactone or β-methyl-δ-valerolactone using an unsaturated monohydroxy compound as a starting species. Examples thereof include Praxel FM series (lactone-modified hydroxyethyl methacrylate) and Praxel FA series (lactone-modified hydroxyethyl acrylate) manufactured by Daicel Chemical Industries, Ltd.

These radical-polymerizable unsaturated group-containing monohydroxy compounds listed above may be used alone or in combination of two or more.

The radical-polymerizable unsaturated group- and anionic hydrophilic group-containing polyurethane resin of the present invention can be produced by a known method similar to that for general polyurethane resins. That is, first, a mixture of a polyhydroxy compound, a radical-polymerizable unsaturated group-containing polyhydroxy compound and an anionic hydrophilic group-containing polyhydroxy compound is reacted with a polyisocyanate compound to obtain an intermediate of the terminal isocyanate group, and then the radical-polymerizable compound. It can be obtained by reacting an unsaturated group-containing monohydroxy compound.

At this time, the temperature of the reaction system is usually 50 to 150.
However, it is preferably 100 ° C. or lower in order to prevent the polymerization of the radically polymerizable unsaturated group, and if necessary, a polymerization inhibitor,
It is advisable to use a urethanization reaction catalyst. The polymerization inhibitor includes hydroquinone, hydroquinone monomethyl ether, hydroquinone mono-t-butyl ether, phenothiazine and the like, and the urethane-forming reaction catalyst includes organic tin compounds such as tin octylate and dibutyltin dilaurate.

In addition, an organic solvent can be used as needed in the production of the polyurethane resin. As these organic solvents,
Acetone, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, butyl acetate, toluene, xylene,
N, N-dimethylformamide, N-methyl-2-pyrrolidone and the like can be mentioned.

In the polyurethane resin of the present invention, the number average molecular weight is preferably 1,000 to 20,000, more preferably 2,000 to 10,000.

The polyurethane resin of the present invention is subjected to chain extension as necessary. That is, in the production of a radically polymerizable unsaturated group- and anionic hydrophilic group-containing polyurethane resin, a free isocyanate group is left as it is, and when it is neutralized with a tertiary amine to be water-solubilized, chain extension is simultaneously performed.
Examples of the chain extender include water, ethylenediamine, diethylenetriamine, propylenediamine, hexamethylenediamine, tolylenediamine, xylylenediamine and isophoronediamine. As the tertiary amine, triethylamine, N, N-dimethylbutylamine, tributylamine, triallylamine, N, N-dimethylallylamine, N-methyldiallylamine, N, N-dimethylethanolamine, N, N-diethylethanolamine, N, N-dibutylethanolamine, N, N-dimethylpropanolamine, N, N-diethylpropanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, N-butyldiethanolamine,
Triethanolamine, triisopropanolamine,
2-dimethylamino-2-methyl-1-propanol,
Examples thereof include N-methylmorpholine and N-ethylmorpholine. These tertiary amines may be used alone or in combination of two or more, depending on the desired properties of the cured product.

In the water-soluble active energy ray-curable resin of the present invention, after neutralization and water solubilization as described above, when an organic solvent is used in the production of polyurethane, this is removed. Further, the resin concentration is adjusted to a value suitable for each field of application depending on the amount of water to be diluted.

The concentration of the radical-polymerizable unsaturated group of the water-soluble active energy ray-curable resin of the present invention is 1,000 per 1 gram equivalent of the radical-polymerizable unsaturated group.
It is desirable that the amount is 0 gram or less, preferably 7000 gram or less. If this weight exceeds 10,000 g, sufficient curing cannot be obtained even when irradiated with active energy rays.

The concentration of the anionic hydrophilic group of the water-soluble active energy ray-curable resin of the present invention is 250 to 200 per 1 gram equivalent of the anionic hydrophilic group.
It is preferably in the range of 0 grams. If the concentration of the anionic hydrophilic group exceeds this range, the water solubility of the resin decreases and a stable aqueous solution cannot be obtained. On the other hand, if the concentration of the anionic hydrophilic group is less than this range, sufficient heat resistance is obtained. Aqueous can no longer be obtained.

The water-soluble active energy ray-curable resin of the present invention thus obtained may be, if necessary, added with water solubility, hot water resistance, storage stability, etc. within a range not departing from the object of the present invention. Within the range that can be retained, in order to impart various functions, a colorant, an extender pigment, a lubricant, a plasticizer,
Additives such as defoaming agents, antioxidants, coupling agents and chelating agents, and other water-soluble resins can be added.

The active energy ray in the present invention is a general term for ionizing radiation such as electron rays, ultraviolet rays or γ rays, electromagnetic waves and the like. Further, in the case of curing by irradiation with ultraviolet rays, if necessary, a photo (polymerization) initiator that generates radicals by irradiation with ultraviolet rays may be added in an amount of about 0.1 to 15 parts by weight with respect to 100 parts by weight of the resin. Good. As a photo (polymerization) initiator, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone, 4-benzoyl -N, N-dimethyl-N
-(2- (1-oxo-2-propenyloxy) ethyl) benzene metamaminium bromide, (4-benzoylbenzyl) trimethylammonium chloride, 2
-Hydroxy-3- (4-benzoylphenoxy)-
N, N, N-trimethyl-1-propenaminium chloride, 2-hydroxy-3- (3,4-dimethyl-9)
-Oxo-9H-thioxanthene-2-yloxy)-
A radical polymerization initiator such as N, N, N-trimethyl-1-propanaminium chloride, which is water-soluble or soluble in an aqueous resin solution, is preferable.

Further, a known and commonly used photosensitizer may be used in combination with such a photo (polymerization) initiator. Such photosensitizers are also preferably amines, ureas, sulfur compounds, phosphorus compounds, chlorine compounds and the like, which are water-soluble or soluble in a resin aqueous solution.

The water-soluble active energy ray-curable resin of the present invention is capable of active energy ray curing due to radically polymerizable unsaturated groups introduced into both molecular side chains and molecular terminals of the polyurethane resin, and has an anion. Water-solubilization is possible by neutralizing the hydrophilic hydrophilic group with a tertiary amine and forming a salt.

[0026]

EXAMPLES Next, the present invention will be described more specifically with reference to examples and application examples. In the following, all parts and percentages are based on weight unless otherwise specified.

Example 1 Methyl ethyl ketone 417 was placed in a 2-liter four-necked flask equipped with a heating device, a stirrer, a thermometer and a reflux condenser.
Parts, polyester 334 parts (Kuraray Co., Ltd. polymethylpentane adipate, number average molecular weight 200)
0), 24.3 parts of glycerol monoacrylate, 2,
2-Dimethylolpropionic acid (44.7 parts), hydroquinone monomethyl ether (0.52 parts) and dibutyltin dilaurate (0.26 parts) were charged to 40 ° C., and 185 parts of isophorone diisocyanate was then added while stirring and blowing dry air. Then, the mixture was heated to 80 ° C. and reacted for 6 hours to obtain an intermediate having an isocyanate group content of 1.30% by weight. Next, 2-hydroxyethyl acrylate 34.8
Parts were added and reacted at 80 ° C. for 15 hours to obtain a radically polymerizable unsaturated group- and anionic hydrophilic group-containing polyurethane resin having an isocyanate group content of 0.16% by weight.

After cooling to 40 ° C., triethylamine 33.
After adding 7 parts, stirring and homogenizing, a 5 liter 4-necked flask containing 1503 parts of deionized water heated to 50 ° C (heating device, stirrer, decanter, reflux condenser, thermometer and aspirator attached ) Was added to the above resin solution for chain extension and water solubilization. Next, the solvent was removed (methyl ethyl ketone) under reduced pressure to obtain a light yellow transparent water-soluble active energy ray-curable resin (A-1). The nonvolatile content of this resin was 30.5% by weight, and the Gardner viscosity was L. The weight of the resin per gram equivalent of the radical-polymerizable unsaturated group was 1340 grams, and the weight of the resin per gram equivalent of the anionic hydrophilic group was 1870 grams.

Example 2 Methyl ethyl ketone 464 was placed in a 2-liter four-necked flask equipped with a heating device, a stirrer, a thermometer and a reflux condenser.
Parts, polyester 251 parts (Kuraray Co., Ltd. polymethylpentane adipate, number average molecular weight 100)
0), glycerol monoacrylate 36.5 parts, 2,
Charge 67.0 parts of 2-dimethylolpropionic acid, 0.58 part of hydroquinone monomethyl ether and 0.29 part of dibutyltin dilaurate to 40 ° C., blow dry air under stirring, and then add 261 parts of tolylene diisocyanate. It was added, heated to 80 ° C., and reacted for 6 hours to obtain an intermediate having an isocyanate group content of 2.30% by weight.
Next, 63.8 parts of 2-hydroxyethyl acrylate was added and reacted at 80 ° C. for 15 hours to give a radically polymerizable unsaturated group- and anionic hydrophilic group-containing polyurethane resin having an isocyanate group content of 0.31% by weight. Obtained.

After cooling to 40 ° C., triethylamine 50.
After 5 parts were added and stirred to be uniform, a 5 liter 4-necked flask containing 1690 parts of deionized water heated to 50 ° C (heater, stirrer, decanter, reflux condenser, thermometer and aspirator attached ) Was added to the above resin solution for chain extension and water solubilization. Next, the solvent was removed (methyl ethyl ketone) under reduced pressure to obtain a light yellow transparent water-soluble active energy ray-curable resin (A-2). The nonvolatile content of this resin was 29.7% by weight, and the Gardner viscosity was R. The weight of the resin per gram equivalent of radically polymerizable unsaturated groups was 870 g, and the weight of the resin per gram equivalent of anionic hydrophilic groups was 1390 g.

Comparative Example 1 Methyl ethyl ketone 354 was placed in a 2-liter four-necked flask equipped with a heating device, a stirrer, a thermometer and a reflux condenser.
Parts, polyester diol 200 parts (polymethylpentane adipate manufactured by Kuraray Co., Ltd., number average molecular weight 100)
0), ethylene glycol 12.4 parts, 2,2-dimethylolpropionic acid 53.6 parts, hydroquinone monomethyl ether 0.44 parts, dibutyltin dilaurate 0.
22 parts were charged to 40 ° C., 222 parts isophorone diisocyanate was added while blowing dry air under stirring, and the mixture was heated to 80 ° C. and reacted for 6 hours to give an intermediate having an isocyanate group content of 1.90% by weight. Got Then 2
-Adding 41.8 parts of hydroxyethyl acrylate,
The reaction was carried out at 80 ° C for 15 hours, and the isocyanate group content was 0.
26% by weight of a polyurethane resin containing a terminal radical-polymerizable unsaturated group and an anionic hydrophilic group was obtained.

After cooling to 40 ° C., triethylamine 40.
After 4 parts were added and stirred to become uniform, a 3 liter four-necked flask containing 1285 parts of deionized water heated to 50 ° C. (heater, stirrer, decanter, reflux condenser, thermometer and aspirator attached ) Was added to the above resin solution for chain extension and water solubilization. Next, the solvent was removed (methyl ethyl ketone) under reduced pressure to obtain a light yellow transparent water-soluble active energy ray-curable resin (A-3). This resin has a nonvolatile content of 29.9% by weight and a Gardner viscosity of O-.
It was P. The weight of the resin per gram equivalent of the radical-polymerizable unsaturated group was 1470 grams, and the weight of the resin per gram equivalent of the anionic hydrophilic group was 1330 grams.

Application Example 1 The resin (A-1) obtained in Example 1 was blended with the following components, thoroughly mixed, and stirred to prepare a pale yellow transparent aqueous coating composition.

Resin (A-1) 100 parts 2-Hydroxy-2-methyl-1-phenyl 2.5 parts Propan-1-one

The above paint thus obtained was applied to an aluminum plate using a drawdown rod # 8, dried with hot air at 80 ° C. for 60 seconds, then irradiated with ultraviolet rays of 100 mJ and cured to a thickness of about 5 μm. A coating film was obtained.

Application Example 2 Instead of the resin (A-1), the resin (A
-Application example 1 except that the same amount as in 2) is used
In the same manner as above, a coating material was obtained, applied and cured. Similar to Application Example 1, the mixture of the following components was light yellow and transparent.

Resin (A-2) 100 parts 2-hydroxy-2-methyl-1-phenyl 2.5 parts propan-1-one

Application Example 3 The resin (A-1) obtained in Example 1 was applied to an aluminum plate using a drawdown rod # 8, and the temperature was raised to 80 ° C.
After hot air drying for 60 seconds, 165 kV-2 mA using an electron beam irradiator Electro Curtain manufactured by ESI USA
Of the electron beam of 30 kGy and cured to obtain a coating film having a thickness of about 5 μm.

Comparative Application Example 1 The resin (A-1) was replaced with the resin (A
Application example 3 except that the same amount as in -3) is used
In the same manner as above, a coating material was obtained, applied, and irradiated with an electron beam.

A performance evaluation test was conducted on each coated plate, and the results are shown in Table 1. The evaluation of each performance was performed by the following methods.

Curability: Evaluation of stickiness by touch with fingers. ◯: No stickiness △: Slight stickiness ×: Severe stickiness

Adhesion: Degree of peeling (%) of the coating film with a cellophane tape after scratches in a grid pattern.

Hardness: Depends on pencil hardness.

Impact resistance: Conditions according to DuPont impact test, 300 gw-30 cm. ◯: No damage (cracking) of the coating film Δ: There is a damaged portion of the coating film ×: Damage of the coating film is severe

Retort resistance: 130 ° C., 2 kgw /
Observe the state of the coating film after being exposed in cm ² of water vapor and water for 30 minutes. ◯: No change in coating film Δ: Change in coating film is observed (whitening, foaming, etc.) ×: Change in coating film is severe

Gel Fraction: MEK when a coated plate was immersed in methyl ethyl ketone (MEK) reflux for 1 hour.
The coating film weight (% by weight) remaining on the coated plate without being extracted.

[0047]

[Table 1]

From Table 1, it is clear that the water-soluble active energy ray-curable resin according to the present invention can form a coating film having excellent hot water resistance and heat resistance.

[0049]

The water-soluble active energy ray-curable resin of the present invention contains no organic solvent, is water-soluble, exhibits good curability upon irradiation with active energy rays, and is excellent in hot water resistance as well. It has various properties and is extremely useful especially for applications such as coating agents, printing inks and plate-making materials.

Claims (4)

[Claims] 1. Obtained by reacting a polyhydroxy compound, a radical-polymerizable unsaturated group-containing polyhydroxy compound, an anionic hydrophilic group-containing polyhydroxy compound, a polyisocyanate compound and a radical-polymerizable unsaturated group-containing monohydroxy compound. A method for producing a water-soluble active energy ray-curable resin, which comprises neutralizing an anionic hydrophilic group of a polyurethane resin with a tertiary amine. 2. The number average molecular weight of the polyurethane resin is 10.
The method for producing a water-soluble active energy ray-curable resin according to claim 1, which is from 0 to 20000. 3. The method for producing a water-soluble active energy ray-curable resin according to claim 1 or 2, wherein the weight per gram equivalent of the radical-polymerizable unsaturated group is 10000 g or less. 4. The method for producing a water-soluble active energy ray-curable resin according to claim 1, 2 or 3, wherein the weight per gram equivalent of the anionic hydrophilic group is 250 to 2000 grams.