JP3185461B2 - Active energy ray-curable water-containing resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an active energy ray-curable water-containing resin composition.

[0002]

2. Description of the Related Art Active energy ray-curable resin compositions are
In addition to being excellent in safety because it does not contain a solvent, it is generally recognized as having excellent characteristics in terms of productivity and energy saving because of its excellent curability. Active energy ray-curable resin compositions, in view of such properties, overcoating agents for various plastic films, paints for woodworking,
It is used as an active ingredient in various coatings such as printing inks and adhesives.

[0003] In the above applications, particularly when the viscosity of the product is required to be reduced, a convenient method such as using a large amount of a reactive diluent or using an organic solvent in combination is usually adopted. However, when a large amount of the reactive diluent is used, problems such as skin irritation and deterioration in curability are likely to occur, and when an organic solvent is used in combination, the risk of air pollution and fire increases.

[0004] Therefore, in recent years, there has been a growing demand for water-based compositions from the viewpoints of air pollution prevention, regulations under the Fire Service Law, occupational safety and health, and the like. Various aqueous active energy ray-curable resin compositions have already been developed. However, the skeleton of the vehicle resin used for them contains (meth)
Since there are relatively many ester sites derived from acrylic acid esters, hydrolysis and performance degradation may occur over time, and gelation may occur during product storage,
At present, satisfactory characteristics have not yet been achieved.

[0005]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances regarding an aqueous active energy ray-curable resin composition,
Aqueous active energy ray-curable resin composition having curability and water resistance comparable to non-aqueous active energy ray-curable resin compositions, relatively low viscosity, low skin irritation and excellent storage stability The purpose is to obtain things.

[0006]

Means for Solving the Problems In order to solve the above-mentioned problems, the present inventors have focused on the vehicle components in the composition and conducted intensive studies on the types of the components and their use ratios. It has been found that by selecting a neutralized salt of a reaction product comprising the following specific components as a vehicle, an excellent aqueous active energy ray-curable resin composition that satisfies the above object can be unexpectedly obtained. The present invention has been completed based on such findings.

That is, the present invention provides an active energy ray-curable water-containing resin composition comprising a vehicle and water as essential components, wherein the vehicle comprises (A) a hydroxyl group-containing acrylate, (B) an organic polyisocyanate, and (C) )
(D) a neutralized salt of a reaction product comprising a fatty acid containing at least one hydroxyl group in the molecule, which is obtained by neutralizing the reaction product with an alkaline substance; Related to the resin composition.

The vehicle in the active energy ray-curable water-containing resin composition of the present invention is a neutralized salt of the reaction product composed of the components (A), (B) and (C) as described above. The component (A) is a hydroxyl group-containing acrylic ester, and includes various types having at least one hydroxyl group and at least one (meth) acryloyl group in the molecule. Specific examples include 2-hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate, polyethylene glycol mono (meth) acrylate, and polypropylene glycol mono (meth) acrylate. And 2-aralkyloxypropyl (meth) acrylates such as 4-hydroxybutyl (meth) acrylate and 2-phenoxypropyl (meth) acrylate, and pentaerythritol triacrylate. These can be used alone or in combination. Component (A) is used in an amount of usually 20 to 60% by weight, preferably 25 to 60% by weight, based on the total amount of the vehicle in the composition.
50% by weight. When a polyol polyacrylate such as polyepoxy acrylate is used, the viscosity of the obtained product tends to increase. Therefore, it is preferable to use the acrylates described above in combination.

The component (B), which is an organic polyisocyanate, includes an organic polyisocyanate having three or more reactive isocyanate groups in the molecule. The molecular weight is preferably about 500 to 1,000. (B)
Specific examples of the component include, for example, trimers obtained from various diisocyanates such as 1,6-hexane diisocyanate, isophorone diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, tolylene diisocyanate, diphenylmethane diisocyanate, and dimethyl isomers. Examples thereof include a prepolymer reacted with a polyhydric alcohol such as propane, and polymethylene polyphenyl polyisocyanate.
The amount of the component (B) to be used is generally 20 to 60% by weight, preferably 25 to 55% by weight, based on the total amount of the vehicle in the composition.

The fatty acid of the component (C) contains at least one hydroxyl group and one carboxyl group in the molecule. The acid value and the hydroxyl value are not particularly limited, but are usually preferably in the range of 150 to 500. Specific examples of the component (C) include, for example, castor oil fatty acid, hydrogenated castor oil fatty acid, and 6-hydroxycaproic acid. The amount of the component (C) to be used is generally 10 to 30% by weight, preferably 15 to 25% by weight, based on the total amount of the vehicle in the composition.

The neutralizing agent of the component (D) includes sodium hydroxide, potassium hydroxide, ammonia and tertiary organic amines, and these can be used alone or in an appropriate combination. Examples of the tertiary organic amine include trimethylamine, triethylamine, N-methyldiethanolamine, and triethanolamine. In addition, 1
The secondary and secondary organic amines are not preferred because they undergo a Michael addition reaction to the (meth) acryloyl group derived from the component (A) and hinder the shelf stability and curability of the obtained water-containing composition.

Hereinafter, a method for producing a vehicle comprising the components (A) to (C) will be described. First, the component (A) and the component (B)
The components are reacted in the above-mentioned proportions to obtain a prepolymer having a free isocyanate group. Next, the prepolymer is reacted with the component (C) at the above-mentioned ratio. The reaction temperature is 40 to 100 ° C, preferably 60 to 80 ° C, and the total reaction time is about 4 to 12 hours. In the urethanization reaction, a known urethanization catalyst such as stannous octylate is preferably used to promote the reaction. Further, in order to prevent polymerization of the component (A) during the urethanization reaction, hydroquinone, methoxyphenol,
Add a polymerization inhibitor such as phenothiazine to the reaction system
5,000 ppm, preferably 50-2000 ppm, or air sealing may be performed.

The reaction product obtained as described above is then neutralized by the component (D) which is a neutralizing agent. Although the degree of neutralization is not particularly limited, it is usually 30 to 100%, preferably 5 to 100%.
The component (D) is usually diluted with water to about 20%, and the diluted solution is preferably gradually charged into the system with stirring. The temperature in the system at the time of neutralization is 50 to 100 ° C, preferably 5
0-80 ° C. After neutralization, water or warm water is added to dilute and cool to a solid content of 20 to 50% by weight to obtain a desired vehicle. In the neutralization step, the above-described operation for preventing the polymerization of the component (A) can be performed, if necessary.

As described above, the active energy ray-curable water-containing resin composition of the present invention is obtained by neutralizing the reaction product of the components (A), (B) and (C) with the component (D). The neutralized salt of the reaction product is used as a vehicle. The water content in the composition is not particularly limited, but is determined in consideration of the viscosity of the resulting composition, workability, stability of the water-containing resin composition, and the like, and is usually 1 to 100 parts by weight of the vehicle.
The range is from 00 to 900 parts by weight. Although the composition does not substantially contain a reactive diluent for the purpose of reducing skin irritation, conventionally known reactive diluents do not adversely affect skin irritation or the stability of the water-containing resin composition. It does not prevent the use of a small amount of the agent.

In the active energy ray-curable water-containing resin composition of the present invention, in addition to the essential components of vehicle and water, a hydrophilic solvent such as a lower alcohol, a coloring agent, a photoinitiator, Additives such as a leveling improver may be appropriately used within a range not departing from the purpose and effect of the present invention. Since the water-containing resin composition of the present invention itself has good standing stability, it is not necessary to add a surfactant, and therefore, the water resistance of the cured film is good, and particularly, the film whitening phenomenon during immersion is prevented. be able to.

The optimum viscosity of the active-energy-ray-curable water-containing resin composition of the present invention cannot be uniquely determined because it varies depending on the application, but it is usually preferably about 2 to 500 cP / 25 ° C.

The active energy ray-curable water-containing resin composition of the present invention obtained as described above has excellent curability and water resistance, and has relatively low viscosity and good stability over time. Various applications in which known non-aqueous active energy ray-curable resin compositions have been used, for example, various coating films such as overcoating agents for plastic films, paints for woodworking, electrodeposition paints, printing inks, paper quality improvers, and the like. Can be applied to a laminating adhesive for paper or plastic film substrates.

[0018]

According to the present invention, the resin composition has curability and water resistance comparable to those of the non-aqueous active energy ray-curable resin composition, and has relatively low viscosity, low skin irritation and good An aqueous active energy ray-curable resin composition having aging stability can be provided.

[0019]

EXAMPLES The present invention will be described below in detail with reference to examples, but the present invention is not limited to these examples. Hereinafter, "parts" and "%" are based on weight unless otherwise specified.

Example 1 In a flask equipped with a stirrer, a thermometer and a reflux condenser,
610.0 parts of HMDI trimer (manufactured by Nippon Polyurethane Co., Ltd., trade name: Coronate HX), 88.6 parts of hydroxypropyl acrylate and 4-methoxyphenol 1.
Charge 2 parts and then stir in stannous octoate.
24 parts were charged and the system was heated. After the fever subsides,
177.2 parts of hydroxypropyl acrylate were gradually added dropwise. Next, the temperature was raised to 75 to 80 ° C. and kept for 1.5 hours. Then, 294.7 parts of castor oil fatty acid and 0.012 parts of a polymerization inhibitor (trade name: Q-1301, manufactured by Wako Pure Chemical Industries, Ltd.) were added, and HMDI3 was added. The remaining isocyanate groups in the monomer were reacted with the hydroxyl groups of castor oil fatty acid. The acid value of the obtained polyurethane acrylate is 38.2 mgKOH
/ G. The polyurethane acrylate (300 parts) was kept at 60 to 70 ° C., neutralized by adding 37.8 parts of a 10% aqueous ammonia solution with stirring, and further added with 662.2 parts of water to obtain an emulsion having a nonvolatile content of 30%. This emulsion had a viscosity of 17.2 cps / 25 ° C. and a pH of 8.6.

Example 2 In the same flask as in Example 1, HMDI trimer 449.
7 parts, 414.4 parts of rosin epoxy acrylate (trade name: Beam Set 101, manufactured by Arakawa Chemical Industries, Ltd.) and 1.2 parts of 4-methoxyphenol, and then, 0.24 parts of stannous octylate under stirring. And the inside of the system was heated. After the exotherm subsided, 118.7 parts of hydroxypropyl acrylate was slowly added dropwise. Then 75
After raising the temperature to ~ 80 ° C and keeping the temperature for 1.5 hours, 217.2 parts of castor oil fatty acid and the polymerization inhibitor (Q-1301)
0.012 parts was added and reacted. The acid value of the obtained urethane acrylate was 29.9 mgKOH / g. 200 parts of the polyurethane acrylate is
C., and 10% aqueous ammonia solution 18.1 under stirring.
And neutralized, and further added 281.9 parts of water to obtain an emulsion having a nonvolatile content of 40%. The viscosity of this emulsion was 9.1 cps / 25 ° C., and the pH was 8.6.

Example 3 In the same flask as in Example 1, HMDI trimer 424.
1 part, 1-hydroxy, 2-phenoxyethyl acrylate (trade name: Light Ester M-, manufactured by Kyoeisha Yushi Co., Ltd.)
600A) 159.2 parts and 4-methoxyphenol 1.2 parts were charged, and then, while stirring, stannous octylate 0.24 part was charged and the system was heated. After the exotherm subsided, 111.9 parts of hydroxypropyl acrylate was gradually added dropwise. Next, the temperature was raised to 75 to 80 ° C. and kept for 1.5 hours, and then 217.2 parts of castor oil fatty acid and 0.012 part of the polymerization inhibitor (Q-1301) were added and reacted. The acid value of the obtained urethane acrylate was 36.8.
mg KOH / g. The polyurethane acrylate (175 parts) was kept at 60 to 70 ° C., neutralized by adding 19.5 parts of a 10% aqueous ammonia solution with stirring, and further treated with water (30 parts).
5.5 parts were added to obtain an emulsion having a nonvolatile content of 35%.
The viscosity of this emulsion is 35.4 cps / 25 ° C., p
H was 8.5.

Example 4 In the same flask as in Example 1, HMDI trimer 608.
Then, 0 parts, 88.3 parts of hydroxypropyl acrylate and 1.2 parts of 4-methoxyphenol were charged, and then 0.24 part of stannous octoate was charged with stirring, and the system was heated. After the exotherm subsided, 176.6 parts of hydroxypropyl acrylate was slowly added dropwise. Then 75 ~
After the temperature was raised to 80 ° C. and kept for 1.5 hours, 297.7 parts of castor oil fatty acid and 0.1 parts of the above polymerization inhibitor (Q-1301) were added.
012 parts were added and reacted. The acid value of the obtained urethane acrylate was 46.5 mgKOH / g. The polyurethane acrylate (200 parts) was kept at 60 to 70 ° C., neutralized by adding 28.2 parts of a 10% aqueous ammonia solution under stirring, and further added with 771.8 parts of water and added with a nonvolatile content of 20%.
Emulsion was obtained. The viscosity of this emulsion is 4
1.6 cps / 25 ° C., pH was 8.6.

Example 5 In the same flask as in Example 1, HMDI trimer 508.
5 parts, pentaerythritol triacrylate 285.
8 parts and 1.2 parts of 4-methoxyphenol were charged,
Next, 0.24 parts of stannous octylate was charged with stirring, and the temperature inside the system was raised. After the exotherm subsided, 156.6 parts of hydroxypropyl acrylate was slowly added dropwise. Next, the temperature was raised to 75 to 80 ° C. and kept for 1.5 hours, after which 248.9 parts of castor oil fatty acid and the polymerization inhibitor (Q-130) were added.
1) 0.012 parts was added and reacted. The acid value of the obtained urethane acrylate was 37.2 mgKOH / g. 200 parts of the polyurethane acrylate is
Keep the temperature at 0 ° C. and stir with a 10% aqueous ammonia solution.
Six parts were added for neutralization, and 777.4 parts of water was further added to obtain an emulsion having a nonvolatile content of 30%. The viscosity of this emulsion was 44.2 cps / 25 ° C., and the pH was 8.6.

(Curing Test) Varnish preparation and curing test of the varnish were carried out on the emulsions (active-energy-ray-curable resin-containing composition) obtained in Examples 1 to 5 under the following conditions, and their film properties were evaluated. Was evaluated. The evaluation results are shown in Table 1.

Preparation of varnish: The above emulsion and a photoinitiator (trade name: Irgacure 184, manufactured by Ciba-Geigy Co., Ltd.) at 5% of the solid content were stirred and mixed until uniform. Curability: The varnish was coated on an ABS plate to a thickness of 5 μm, dried with hot air at 80 ° C. for 1 minute, and then irradiated with ultraviolet light from a high-pressure mercury lamp of 80 W / cm until the film became tack-free. It was evaluated in terms of energy (mJ). Preparation of cured film: In the evaluation of pencil hardness, solvent resistance, and water resistance, a cured film obtained by preparing the same dry film and irradiating the film with 100 mJ of ultraviolet light to cure the film was used. Pencil hardness: according to JIS-K-5400. Solvent resistance: After the cured film was left in MEK for 24 hours, changes in appearance were visually observed. Water resistance: After the cured film was left in deionized water for 24 hours, changes in appearance were visually observed.

[0027]

[Table 1]

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI C09D 5/02 C09D 5/02 175/16 175/16 Examiner Osamu Onodera (56) References JP 50-18595 (JP, A) JP-A-53-115307 (JP, A) JP-A-4-211413 (JP, A) JP-A-6-256418 (JP, A) JP-A-4-248822 (JP, A) JP-A-5-306322 ( JP, A) JP-A-6-93066 (JP, A) JP-A-5-339307 (JP, A) JP-A-6-87939 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , (DB name) C08F 290/00-290/14 C08F 299/00-299/08 C08F 2/46-2/50 C08F 20/00-20/70 C08F 120/00-120/70 C08F 220/00-220 / 70 C08G 18/67 C09D 1/00-201/10

Claims (2)

(57) [Claims] 1. An active energy ray-curable water-containing resin composition comprising a vehicle and water as essential components, wherein the vehicle comprises (A) a hydroxyl group-containing acrylate, and (B) a reactive isocyanate group in the molecule. And (C) a neutralization salt of the reaction product obtained by neutralizing a reaction product comprising an organic polyisocyanate having at least one hydroxyl group and (C) a fatty acid having at least one hydroxyl group in a molecule with (D) an alkaline substance. An active energy ray-curable water-containing resin composition, which is characterized in that: 2. The method of claim 2, wherein (A) :( B):
(C) = 20-60: 20-60: 10-30 (weight
%), The active energy ray-curable water-containing composition according to claim 1.
Resin composition.