JP3202066B2 - Low temperature curing type aqueous resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an aqueous polyurethane resin which is excellent in curability at low temperatures, scuff resistance, solvent resistance and hot water resistance, and is useful as a low-temperature curing agent useful as a paint, an adhesive or a surface coating agent. The present invention relates to a mold-type aqueous resin composition.

[0002]

2. Description of the Related Art Water-based polyurethane resins are used as sealers or top coats for paints, adhesives, water-based inks, leather, paper, metals, plastics, wood, rubber, inorganic materials, and the like. It is not always sufficient for scuffing, solvent resistance and warm water resistance.

There is a method of improving performance by using a polyfunctional aziridine, a water-soluble epoxy or the like as a curing agent, but there are problems to be solved in terms of curability at low temperatures, pot life, hydrolysis and the like.

[0004]

DISCLOSURE OF THE INVENTION In order to solve the above-mentioned problems, the present invention has made intensive studies and found that diols and polyols having a carboxyl group in the molecule and polyols obtained by the esterification of fats and oils with polyhydric alcohols are used. found an aqueous urethane resin is anionized obtained using an aqueous resin composition obtained by reacting an epoxy compound, scuffing resistance at low temperature curing, the better the solvent resistance and warm water resistance, the The invention has been completed.

[0005]

Means for Solving the Problems The present invention, Cal in the molecule
With diols, polyols and fats and oils having a boxyl group
Polyesters that are umesterified with polyhydric alcohols
An anionized aqueous urethane resin obtained by using
The equivalent ratio of the epoxy group to the carboxyl group in the aqueous urethane resin is a crosslinking reaction with an epoxy compound having a molecular weight of 70 to 4000 added to a ratio of 0.02 to 0.7 to form a carboxyl group and a double bond. A low-temperature-curable aqueous resin composition comprising a hardening accelerator as a metal component in an amount of 0.005 to 0.2 part by weight based on 100 parts by weight of a solid component of the aqueous resin.

The aqueous urethane resin used in the present invention is produced, for example, as follows.

That is, an aqueous urethane resin is obtained by reacting a diol, a polyol having a carboxyl group, a polyol obtained by esterifying an oil or fat with a polyhydric alcohol and a polyisocyanate, and a terminal isocyanate group having a carboxyl group and a double bond. To synthesize a urethane prepolymer, and then drop the urethane prepolymer into deionized water containing a basic organic compound and an extender to perform ion addition by a chain extension reaction and a carboxyl group neutralization reaction. An aqueous urethane resin having a carboxyl group and a double bond anionized by the above is preferably used.

The urethane prepolymer in the above reaction is adjusted so that the isocyanate group content (in terms of solid content) is 0.5 to 10%, preferably 0.8 to 4%. If the isocyanate group content is 0.5% or less, it is difficult for the molecular weight to become sufficiently large in the chain elongation reaction.
The amount of carbon dioxide gas generated in the chain extension reaction is too large, and it is difficult to produce.

In the above reaction, the amount of the diol having a carboxyl group is 1 as an acid value (in terms of solid content).
It is set to be 0 or more, preferably 15 or more. If the acid value is less than 10, self-emulsification becomes difficult, the particle size becomes large, and stability tends to be poor.

The above-mentioned urethane prepolymer can be produced by a known method which is exactly the same as the so-called urethane prepolymer usually used for producing a polyurethane resin.

The above isocyanate compound includes, for example, 1,4-tetramethylene diisocyanate,
Aliphatic isocyanates such as 6-hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,8-diisocyanatomethylcaproate, 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate, methylcyclohexyl Alicyclic disissocyanates such as -2,4-diisocyanate, toluylene diisocyanate, diphenylmethane diisocyanate, 1,5-naphthene diisocyanate, diphenylmethylmethane diisocyanate,
Tetraalkyldiphenylmethanediisonate, 4,
One or a mixture of two or more aromatic diisocyanates such as 4-dibenzyl diisocyanate and 1,3-phenylene diisocyanate, chlorinated diisocyanates, brominated diisocyanates, and a polyisocyanate compound which is an adduct with water is used. Can be

As the above-mentioned carboxyl group-containing diol, any one can be used as long as a carboxyl group is imparted in a branched manner in a linear prepolymer molecule.
In order to increase the carboxyl group content in the prepolymer, a low molecular weight diol having at least one branched carboxyl group and having 3 to 10 carbon atoms is preferable, and for example, 2,2-dimethylolpropionic acid and the like are preferable. .

The polyol used in the present invention includes:
Known polyols commonly used in the production of urethane resins, for example, diethylene glycol, butanediol,
Hexanediol, neopentyl glycol, bisphenol A, cyclohexanedimethanol, trimethylolpropane, glycerin, pentaerythritol, polyethylene glycol, polypropylene glycol, polyester polyol, polycaprolactone, polytetramethylene ether glycol, polythioether polyol, polyacetal polyol, polybutadiene polyol , Flangemethanol, and the like, or a mixture of two or more thereof.

These polyols can be appropriately selected according to the purpose and application, and the required physical properties such as hard and soft can be easily designed.

[0015] As the polyol which is used in the present invention and is obtained by esterifying an oil and fat with a polyhydric alcohol, the oil and fat having an iodine value of 7 to 200 and a polyhydric alcohol such as trimethylolpropane and pentaerythritol are umesterified. XP1076E, XP1077E, XP1
580E, FB20-50XB (Mitsui Toatsu Chemical Co., Ltd.)
Commercially available products such as those manufactured by T.I.

The epoxy compound used in the present invention has a molecular weight of 70 to 4000, and the following commercially available epoxy compounds can be used.

For example, Epocoat 1001, Epicoat 1002, Epicoat 1004, Epicoat 1007,
Epicoat 1009, Epicoat 828, Epicoat 1
52, Epicoat 154 (trade name, manufactured by Shell Chemical Co., Ltd.), Epolite 400E, Epolite 200E, Epolite 40E, Epolite 80MF (trade name, manufactured by Kyoeisha Yushi Kagaku Kogyo Co., Ltd.), Denacol EX810, 81
1,851,830,832,841,861,91
1,941,920,921,931,211,21
2,221,721,313,314,321,42
1,512,521,611,612,614,614
B, 622 (trade name, manufactured by Nagase Kasei Kogyo Co., Ltd.) and the like.

The equivalent ratio of the epoxy group to the carboxyl group in the aqueous urethane resin having an anionized carboxyl group and double bond is 0.02 to 0.7, preferably 0.02 to 0.35.

In the production of the aqueous urethane resin used in the present invention, the urethane prepolymer is prepared by using a solvent and / or
Alternatively, dissolve or suspend in water and react with a carboxyl group to add a basic compound and the following extender for increasing hydrophilicity, or dissolve the basic compound and the extender in a solvent and / or water. Then, the urethane prepolymer is made hydrophilic by, for example, dropping a urethane prepolymer solution, and then reacting with an elongating agent. Then, dehydration and dehydration are performed until the concentration of non-volatile components becomes 30 to 45%. And / or desolvation and further 70
Reaction at ~ 90 ° C for about 6 hours, reaction rate is 50-100%
The reaction is carried out by reacting a carboxyl group and an epoxy group until the reaction becomes.

Suitable extenders used in the present invention are, for example, water and polyamines. Examples of the polyamines include ethylenediamine, diethylenetriamine, triethylenetetramine, propylenediamine, butylenediamine, hexamethylenediamine, and the like. Cyclohexylenediamine, piperazine, 2-methylpiperazine, phenylenediamine, tolylenediamine, xylenediamine, α, α′-methylenebis (2-chloroaniline) 3,3′-dichloro-α, α′-biphenylamine, m- Xylene diamine, isophorone diamine, N
Adducts of -methyl-3,3'-diaminopropylamine and diethylenetriamine with acrylates or hydrolysis products thereof.

As the basic organic compound for imparting hydrophilicity by reacting with a carboxyl group, any of known organic compounds can be used. Particularly preferred examples include dimethylethanolamine, diethylethanolamine, triethylamine and the like. Can be

The curing accelerator used in the present invention includes:
Known materials which are usually used as a curing accelerator for unsaturated resins can be used. For example, cobalt naphthenate, calcium naphthenate, lithium naphthenate, manganese naphthenate, lead naphthenate, zinc naphthenate, copper naphthenate, zirconium naphthenate, cobalt octylate, calcium octylate, manganese octylate, copper octylate, Lead octylate, zinc octylate, zirconium octylate, aluminum octylate, stannous octylate,
Water-soluble cobalt and water-soluble curing accelerators include W
-O cobalt, WO manganese, W-cobalt, W-lead (trade name, manufactured by Toei Kako Co., Ltd.), DICATATE 311
1 (manufactured by Dainippon Ink and Chemicals, Inc., trade name) and the like. The above-mentioned curing accelerator is usually used as a metal component in an amount of 0.005 to 0.5 wt.
It is used in an amount of 2 parts by weight, preferably 0.03 to 0.15 parts by weight.

The solvent used in the present invention includes methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate,
Examples thereof include toluene, xylene, isobutyl acetate, butyl acetate, acetone, dimethylformamide, N-methyl-2-pyrrolidone, and diethylene glycol dimethyl ether.

The aqueous resin used in the present invention may be, if necessary, an organic solvent, a pigment, a dye, an emulsifier, a surfactant, a thickener, a heat stabilizer, a leveling agent, an antifoaming agent, a filler, an anti-settling agent, It may contain other conventional components such as a UV absorber, an antioxidant, and a viscosity reducing agent.

The low-temperature curable aqueous resin composition of the present invention can be blended with an acrylic emulsion, a rubber emulsion, or another aqueous resin.

The aqueous urethane copolymer obtained by copolymerizing the low-temperature curing type aqueous resin composition of the present invention with at least one vinyl monomer such as acrylic acid, methacrylic acid ester, vinyl chloride, styrene, acrylonitrile, vinyl acetate, etc. A resin composition can be used, and a copolymer of these vinyl monomers and an aqueous resin composition can be formed into a hybrid, thereby improving the performance.

[0027]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to these examples.

Example 1 (Synthesis of urethane prepolymer) XP was placed in a 2000 ml four-necked flask equipped with a thermometer, a stirrer, and a nitrogen inlet tube.
1077E (trade name, umami esterified polyol of linseed oil and pentaerythritol manufactured by Mitsui Toatsu Chemicals, Inc.)
115.4 g of molecular weight 638, iodine value 133), 71.2 g of polytetramethylene ether glycol having a molecular weight of 2000, 5.8 g of trimethylolpropane, 21.5 g of dimethylolpropionic acid, and 34.5 of N-methyl-2-pyrrolidone. 4 g, 90 ° C. while introducing nitrogen
And the contents were dissolved. Next, the mixture was cooled to 40 ° C., and 86.5 g of acetone was added. When the internal temperature reached 30 ° C., 86.2 g of tolylene diisocyanate was added in 1 part.
It was dropped over time. After maintaining the internal temperature at 30 to 40 ° C. and performing the reaction for 8 hours, the mixture was diluted with 86.5 g of acetone.
The NCO group content of this urethane prepolymer is 0.9
%, And Epicoat 1001 (trade name, manufactured by Shell Chemical Co., Ltd., molecular weight 90) as an epoxy compound.
0, an epoxy equivalent of 450) was added to prepare a urethane prepolymer mixed with an epoxy compound.

(Synthesis of Aqueous Dispersion of Urethane Prepolymer) 485 g of deionized water containing 12.1 g of dimethylethanolamine was kept at 40 ° C., and a urethane prepolymer mixed with the above-mentioned epoxy compound was added dropwise to the mixture.
After performing decompression acetone at ℃, keep the internal temperature at 70 ℃,
Ionization of carboxyl groups and chain elongation of NCO groups were conducted over 6 hours, and then deacetone was performed under reduced pressure at 40 ° C., and nonvolatile content was 39.0%, viscosity was 650 cps / 25 ° C., pH
An aqueous urethane resin dispersion was obtained in which an epoxy compound having an acid value of 7.7 and an acid value of 30.0 KOH mg / g (as solid content) was mixed.

(Synthesis of Aqueous Resin) The above-mentioned aqueous urethane resin dispersion mixed with an epoxy compound was maintained at an internal temperature of 70 ° C., and the equivalent ratio of epoxy groups to carboxyl groups was 0.033 over 6 hours. , And as a double bond curing accelerator, DICNATE 3111 (trade name,
20.0 g of a water-soluble cobalt naphthenate manufactured by Dainippon Ink and Chemicals, Inc. was added, and finally, the nonvolatile content was 39%.
pH 8.6, viscosity 550 cps / 25 ° C., acid value 29.0
A low-temperature curable aqueous resin composition having a KOH mg / g (solid content conversion) was obtained.

Example 2 Under the same conditions as in Example 1, the epicoat 1001
8 g, and the epoxy group was reacted with the carboxyl group at an equivalent ratio of 0.219 to obtain a nonvolatile content of 40.0%.
%, PH 8.9, viscosity 500 cps / 25 ° C., acid value 2
A low-temperature-curable aqueous resin composition of 3.4 KOHmg / g (solid content) was obtained.

Example 3 Under the same conditions as in Example 1, the epicoat 1001 was
9 g, and the epoxy group was reacted with the carboxyl group at an equivalent ratio of 0.733 to obtain a nonvolatile content of 41.0%.
%, PH 9.1, viscosity 520 cps / 25 ° C., acid value 8.
A low-temperature-curable aqueous resin composition of 0 KOH mg / g (in terms of solid content) was obtained.

Example 4 Under the same conditions as in Example 2, XP1076E (umesterified polyol of safflower oil and pentaerythritol manufactured by Mitsui Toatsu Chemicals, Inc., molecular weight 638, iodine value 12
7.5) to 115.4 g, and the reaction was carried out.
A low-temperature-curable aqueous resin composition having a pH of 8.7, a viscosity of 540 cps / 25 ° C., and an acid value of 23.2 KOH mg / g (in terms of solid content) was obtained.

Example 5 Under the same conditions as in Example 2, DICNATE 3111 (a water-soluble cobalt naphthenate manufactured by Dainippon Ink and Chemicals, Inc.) was changed to cobalt naphthenate, and 1.6 g was mixed in a urethane prepolymer and synthesized. And a non-volatile content of 39.1%, pH
8.7, viscosity 610 cps / 25 ° C, acid value 23.2 KO
A low-temperature-curable aqueous resin composition of Hmg / g (in terms of solid content) was obtained.

Example 6 (Synthesis of urethane prepolymer) XP was placed in a 2000 ml four-necked flask equipped with a thermometer, a stirrer, and a nitrogen inlet tube.
1077E (um esterified polyol of linseed oil and pentaerythritol manufactured by Mitsui Toatsu Chemicals, Inc., molecular weight 6
38, 104.6 g of iodine value 133), molecular weight 200
Of polytetramethylene ether glycol of 64.5
g, 5.2 g of trimethylolpropane, 21.5 g of dimethylolpropionic acid, and 34.4 g of N-methyl-2-pyrrolidone, and heated to 90 ° C. while introducing nitrogen to dissolve the contents. .

Then, the mixture was cooled to 55 ° C., charged with 85.8 g of ethyl acetate, and then charged with 104.1 g of isophorone diisocyanate.

After maintaining the internal temperature at 80 to 95 ° C. and performing the reaction for 8 hours, the mixture was diluted with 85.8 g of ethyl acetate. The NCO group content of this urethane prepolymer was 0.9%. Further, as an epoxy compound, Epicoat 100
15.8 g of 1 was added, and a urethane prepolymer mixed with an epoxy compound was prepared.

(Synthesis of Aqueous Dispersion of Urethane Prepolymer) A urethane prepolymer mixed with the above-mentioned epoxy compound was neutralized with 13.8 g of triethylamine and then dropped into deionized water at 40 ° C. to ionize carboxyl groups and to form N
The CO group was extended with a chain, and ethyl acetate was removed under reduced pressure at 50 ° C. to obtain a nonvolatile content of 39.0%, a pH of 8.7, and a viscosity of 620.
An aqueous urethane resin dispersion in which an epoxy compound having a cps / 25 ° C. and an acid value of 29.9 KOH mg / g (solid content) was mixed was obtained.

(Synthesis of Aqueous Resin) The above-mentioned aqueous urethane resin dispersion mixed with an epoxy compound was maintained at an internal temperature of 70 ° C., and the equivalent ratio of epoxy group to carboxyl group was 0.219 over 6 hours. And finally, a nonvolatile content of 39.0%, a pH of 8.7, and a viscosity of 620 cps / 25.
A low-temperature-curable aqueous resin composition having an acid value of 23.5 KOH mg / g (in terms of solid content) at 2 ° C. was obtained.

Comparative Example 1 In a 2000 ml four-necked flask equipped with a thermometer, a stirrer, and a nitrogen inlet tube, 83.7 g of polytetramethylene ether glycol having a molecular weight of 2,000, 51.6 g of neopentyl glycol, and trimethylolpropane 4 were added. .2g,
34.4 g of dimethylolpropionic acid was charged, and the temperature was raised to 90 ° C. while introducing nitrogen to dissolve the contents.

Next, the mixture was cooled to 40 ° C., 86.0 g of acetone was added, and when the internal temperature reached 30 ° C., 139.0 g of tolylene diisocyanate was added dropwise over 1 hour.

After the reaction was carried out for 8 hours while maintaining the internal temperature at 30 to 40 ° C., the mixture was diluted with 86.0 g of acetone.

The urethane prepolymer had an NCO% group content of 0.88%.

While maintaining at 40 ° C. 481.5 g of deionized water containing 12.1 g of dimethylethanolamine, the above-mentioned urethane prepolymer was added dropwise, and deacetone was performed at 40 ° C. under reduced pressure. 2%, pH
7.6, viscosity 400cps / 25 ° C, acid value 25.0KO
An aqueous polyurethane resin of Hmg / g (in terms of solid content) was obtained.

Comparative Example 2 A compound was synthesized under the same conditions as in Example 2 without using an epoxy compound, and had a nonvolatile content of 38.9%, a pH of 7.9, and a viscosity of 690.
An aqueous polyurethane resin having a cps / 25 ° C. and an acid value of 30.0 KOH mg / g was obtained.

Comparative Example 3 In a 2000 ml four-necked flask equipped with a thermometer, a stirrer and a nitrogen inlet tube, 71.7 g of polytetramethylene ether glycol having a molecular weight of 2000, 44.2 g of neopentyl glycol, and trimethylolpropane 3 were added. 0.6 g,
Dimethylolpropionic acid 21.5 g, N-methyl-2
-34.3 g of pyrrolidone was charged, and the temperature was raised to 90 ° C while introducing nitrogen to dissolve the contents.

The mixture was cooled to 55 ° C., charged with 85.8 g of ethyl acetate, and then charged with 158.9 g of isophorone diisocyanate.

After maintaining the internal temperature at 80 to 95 ° C. and performing the reaction for 8 hours, the mixture was diluted with 85.8 g of ethyl acetate.

The urethane prepolymer had an NCO% group content of 0.92%. After neutralizing the above urethane prepolymer with 13.8 g of triethylamine, the mixture was added dropwise to deionized water at 40 ° C. to cause a reaction. Further, ethyl acetate was removed at 50 ° C. under reduced pressure.
7.1, viscosity 590cps / 25 ° C, acid value 25.2KO
An aqueous polyurethane resin of Hmg / g (in terms of solid content) was obtained.

Comparative Example 4 A compound was synthesized under the same conditions as in Example 6 except that no epoxy compound was used. The nonvolatile content was 38.9%, the pH was 7.6, and the viscosity was 67.
0.0cps / 25 ° C, acid value 30.0KOHmg / g
An aqueous polyurethane resin (solid content) was obtained.

Evaluation of organic solvent resistance and hot water resistance: aqueous urethane resin compositions of Examples 1 to 6 and Comparative Examples 1 to 4
The aqueous polyurethane resin composition was adjusted to have a non-volatile content of 35% by adding deionized water, dried on a glass plate and a mild steel mild steel plate (JIS.G.3141), and then coated with a bar coater to a thickness of 10 microns.

The coating film was dried in a constant temperature and humidity room at a temperature of 20 ° C. and a humidity of 60% for 7 days and subjected to a performance test. Embodiment 6 uses DI
CNATE3111 (trade name, Dainippon Ink and Chemicals, Inc.)
5% water-soluble cobalt naphthenate)
Was added and subjected to the test.

[0053]

[Table 1] Test method and evaluation criteria Solvent resistance: Solvent was immersed in gauze and rubbed the coating surface 50 times and observed the surface state ×: Dissolved the film within 50 times or less △: Glossy ○: Slightly glossy ◎: Test Maintain the previous state Warm water resistance: Dipped in boiling water for 4 hours to observe whitening state ×: Whitening (no transparency at all) △: General whitening ◎: No whitening Evaluation of scuff resistance: Test method and evaluation criteria Scuff resistance: Kick off at the bottom of badminton shoes and observe the surface condition of the coating film ×: Glossy with scratches △: Glossy ◎: Gloss without scratches

[0054]

[Table 2]

[0055]

It is apparent from Tables 1 and 2 that the low-temperature curing type aqueous resin composition obtained in the present invention is excellent in solvent resistance, hot water resistance, and scuff resistance during low-temperature curing.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI C09D 175/04 C09D 175/04 C09J 175/04 C09J 175/04

Claims (8)

(57) [Claims] 1. A diol having a carboxyl group in the molecule.
Of polyols, polyols and fats with polyhydric alcohols
Anionization obtained using stealized polyols
Water-based urethane resin , the equivalent ratio of epoxy groups to carboxyl groups in the aqueous urethane resin is 0.02 to 0.02.
A crosslinking reaction is carried out with an epoxy compound having a molecular weight of 70 to 4000 added to a ratio of 0.7, and a curing accelerator is added to the obtained water-based resin having a carboxyl group and a double bond in an amount of 100 parts by weight in terms of a solid component. 0.005-0.
A low-temperature-curable aqueous resin composition comprising 2 parts by weight. 2. An aqueous urethane resin, wherein a terminal isocyanate group having a carboxyl group and a double bond by reacting a polyisocyanate with a diol, a polyol having a carboxyl group and a polyol obtained by esterifying an oil or fat with a polyhydric alcohol. To synthesize a urethane prepolymer, and then drop the urethane prepolymer into deionized water containing a basic organic compound and an extender to perform ion addition by a chain extension reaction and a carboxyl group neutralization reaction. The low-temperature curing type aqueous resin composition according to claim 1, which is an aqueous urethane resin having a carboxyl group and a double bond anionized by the above. 3. The low-temperature curing type aqueous resin composition according to claim 2, wherein the curing accelerator is an organometallic compound. 4. The low-temperature-curable aqueous resin composition according to claim 2, wherein the iodine value of the fat or oil is from 7 to 200. 5. The urethane prepolymer having a terminal isocyanate group has an isocyanate group content of 0.5 to 10% in terms of solid content.
The low-temperature curing type aqueous resin composition according to the above. 6. A diol having a carboxyl group,
The low-temperature-curable aqueous resin composition according to claim 2, which is 2,2-dimethylolpropionic acid. 7. The low-temperature curing type aqueous resin composition according to claim 2, wherein the elongation agent is water or a polyamine. 8. The low-temperature-curable aqueous resin composition according to claim 2, wherein the basic organic compound is dimethylethanolamine, diethylethanolamine or triethylamine.