JPS6043851B2 - Curable resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a curable resin composition, and more particularly to a resin composition that has virtually no adverse effects on the human body and has excellent curability and physical properties of the cured resin.

In recent years, there has been a growing trend to utilize photocurable paints and coating resins for the purpose of environmental purification, such as energy saving and prevention of solvent volatilization.

There are many types of photocurable resins, but most of those used for printing inks and paints are oligomers or polymers containing acryloyl groups, methacryloyl groups, or both. It is classified into many types depending on the bonding mode of the molecules, and resins with diverse properties have been obtained.

These photocurable resins include, for example (1) epoxy acry(methacry)lates, which are the reaction products of epoxy resins with acrylic or methacrylic acids or mixtures thereof, (2) unsaturated alcohols, isocyanates and polyhydroxyl. (3) polyester acrylates synthesized by esterification of acrylic acid or methacrylic acid or mixtures thereof with polybasic carboxylic acids and polyhydric alcohols, corresponding methacrylates or Mention may be made of their acrylate methacrylate mixed oligomers or polymers or mixtures thereof. Since the above-mentioned oligomers or polymers generally have high viscosity and viscosity, when actually used, acrylic acid esters of polyhydric alcohols with a low viscosity of 1 poise or less, such as hexanediol diacrylate, are used as diluents and crosslinking agents. Trimethylolpropane triacrylate, etc. must be used in combination.

Although each of these photocurable resin compositions has excellent physical properties, there are many points that need improvement.

The biggest drawback is that the polyhydric alcohol acrylate (hereinafter abbreviated as polyfunctional acrylate) used as a diluent has an adverse effect on the human body, i.e. skin irritation and rashes. This is currently the biggest obstacle, and it is no exaggeration to say that the success or failure of photocurable resin coatings will depend on whether or not this adverse effect on the human body can be eliminated. However, the removal of this negative effect on the human body is not only required for photocurable resins, but also the epoxy acrylate, acrylic urethane, polyester acrylate, etc. mentioned above as examples of photocurable resins are It is also highly desirable for curing with azo compounds such as azobisisobutyronitrile.

Therefore, there has been a strong demand for compositions that do not have any adverse effects on the human body, such as skin irritation, when using the above-mentioned resins, whether photo-cured or organic peroxide-cured. The present inventors have made various studies to solve this problem, and have found that in order to avoid using the above-mentioned skin-irritating polyfunctional acrylate as a diluent, the above-mentioned epoxy, which is a base component of a resin composition, This inevitably involves lowering the molecular weight and changing the structure of oligomers or polymers such as acrylate, acrylic urethane, and polyester urethane, but this also reduces the physical properties of the cured resin, making it difficult to obtain a coating film with desired properties. As a result, I realized that there were many practical problems.

That is, epoxy acrylates, such as epoxy trees of the bisphenol A diglycidether type. Epoxy acrylate obtained by reacting fat with acrylic acid has a viscosity as high as several thousand poise, so it is essential to dilute it with a polyfunctional acrylate that is irritating to the skin.

The physical properties of the cured resins obtained in this way are generally excellent, and despite the skin irritation of the diluent. Its use is forced.
On the other hand, epoxy acrylate obtained by the reaction of adipic acid diglycidyl ester and acrylic acid has a low viscosity of several tens of poise and can be used without a diluent depending on the application, but the physical properties of the cured resin are bisphenol type. Not as good as epoxy acrylate.

In this way, in combination with known acrylate (methacrylate) oligomers or polymeric polyfunctional acrylates, a resin composition that has almost no adverse effects on the human body and can provide a cured coating film with good physical properties has yet to be found. I can say no.

In any case, the only way to reduce the impact on the human body is to use harmless prepolymers and diluents, and it was necessary to develop such prepolymers and diluents. As a result of repeated studies along this line, they found that acrylates of polyhydric alcohols, such as polyhydric acrylates of diarylidene pentaerythrite, polyester acrylates,
Epoxy-acrylate, unsaturated acrylic urethane,
Skin irritation is of a level that does not cause any practical problems, so
As a diluent or a physical property improver, at least one of an acryloyl group and a methacryloyl group and a hydroxyl group are added to the cycloacetal having one or more allyl ether type unsaturated bonds in the same molecule. The object of the present invention is mainly focused on cycloacetal acrylate (or methacrylate) having one or more acryloyl group or methacryloyl group or both in one molecule as an unsaturated bond, which is obtained by reacting an unsaturated alcohol with a saturated alcohol. found a match,
The present invention was completed.

A typical example of a cycloacetal containing an acryloyl group, a methacryloyl group, or both, which is a component of the curable resin composition of the present invention, is 2-hydroxyethyl acrylate, isopropyl alcohol, and di- Mention may be made of cycloacetal acrylate obtained by reaction with arylidene pentaerythrite.

Although the above-mentioned cycloacetal acrylate has a molecular weight of 300 or more, its viscosity is as low as 1 to 5 poise, and hardly any skin irritation is observed.

Therefore, when this cycloacetal acrylate is used in combination with other photocurable or acrylate oligomer or polymer base components that are curable with organic peroxides or azo compounds, the viscosity of the base component must be adjusted to the desired level. A hygienically safe resin that can be photocured or cured with an organic peroxide or an azo compound. As shown in Examples below, it is possible to obtain a resin composition whose cured resin has good physical properties. Cycloacetal acrylate, which is the active ingredient of the present invention, must contain one or more acryloyl double bonds or methacryloyl double bonds, or both, and must have a low viscosity because it serves as a crosslinking agent and diluent. desirable.

(1) The unsaturated alcohol component containing at least one acryloyl group and methacryloyl group and a hydroxyl group in the same molecule constituting the captive component of the present invention is 2
-Hydroxyethyl acrylate, 2-hydroxypropyl acrylate, neopentyl glycol monoacrylate, 2・2●4-trimethylpentanediol-1
- Mention may be made, without limitation, of 3-monoacrylate, hexanediol monoacrylate, trimethylolpropane diacrylate, pentaerythritol triacrylate and their corresponding methacrylates.

As the saturated alcohol (2) constituting the component (4) of the present invention, various saturated alcohols such as aliphatic, alicyclic, and aromatic alcohols can be used. For example, C4 to C8 alcohols are preferable as the aliphatic alcohol. For example, butanol, amyl alcohol, octyl alcohol, isononyl alcohol, etc. are easy to use.

Representative examples of the alicyclic alcohol include cyclohexanol and cyclohexyl cellosolve, and representative examples of the aromatic alcohol include benzyl alcohol and benzyl cellosolve. Furthermore, alcohols that are polyhydric alcohol esters of fatty acids and have one hydroxyl group in the molecule, such as diglyceride of linseed oil fatty acids, have a double bond in the molecule and are not saturated alcohols, but the double bond is an acryloyl group. Since it is not active in radical polymerization like a methacryloyl group, it can be treated in the same manner as a saturated alcohol, and the saturated alcohol in the present invention includes alcohols having such a double bond. Furthermore, glycol monoesters and monoethers can also be used, making it possible to obtain distinctive products. The reason for using the above-mentioned saturated alcohols is that by using these alcohols and by selecting the type, the physical properties of the cured product can be greatly changed, and because of changes in type and amount, liquid resin The main advantages are that the viscosity and curing properties of resins can be adjusted, and that they are also useful for improving the stability of resins, and that the range of modification can be greatly expanded.

As the cycloacetal (3) constituting the prison component of the present invention, diarylidene pentaerythritol is particularly preferred, but other cycloacetals such as triarylidene sorbitol can be used.

However, there are few advantages in terms of cost and physical properties. the above(
The reaction for synthesizing component (4) from components 1), (2) and (3) is carried out in the presence of a cationic catalyst, and the yield is quantitative.

Examples of acrylate (methacrylate) oligomers or polymers used in combination with the cycloacetal acrylate of the present invention include the following.

(1) Condensates of polyhydric alcohols containing at least one of acryloyl groups and methacryloyl groups in one molecule, or mixtures of the above condensates, such as diacrylates, triacrylates, and tetraacrylates of dipentaerythrite. acrylates, pentaacrylates or hexaacrylates or the corresponding methacrylates or diacrylates, triacrylates, tetraacrylates or the corresponding methacrylates of ditrimethylolpropane,
Tripentaerythritol diacrylate, monotriacrylate, tetraacrylate, pentaacrylate,
Hexaacrylate, heptaacrylate, octaacrylate and the corresponding methacrylate, diacrylate, triacrylate or tetraacrylate of pentaerythrite or the corresponding methacrylate, (2)
Polyester acrylate (methacrylate) containing at least one of acryloyl groups and methacryloyl groups in one molecule, or a mixture thereof or an acrylate-methacrylate mixed polyester, (3) 1
Acrylic urethane or a mixture thereof containing at least one of two or more acryloyl groups and methacryloyl groups in the molecule.

(4) Epoxy acrylate (vinyl ester resin) containing at least one of two or more acryloyl groups or methacryloyl groups in one molecule, or a mixture thereof.

If the molecular weight of the acrylate oligomer or acrylate polymer is less than 300, it generally tends to cause strong skin irritation and is therefore not suitable for the purpose of the present invention.

Moreover, if the molecular weight is 5000 or more, the viscosity becomes too high and handling becomes difficult, and furthermore, no improvement in physical properties is observed, so it can be said that this is not necessary. The ratio of cycloacetal acrylate (component A) and acrylate oligomer (component B) used in the resin composition of the present invention can be changed at any ratio depending on the coating method and the required physical properties of the cured product. However, cycloacetal acrylate generally accounts for 10 to 9%, preferably 20 to 8%, of the total amount of the active ingredient and component (B).

Further, a radical generator was added to the resin composition in an amount of 10%.
It is necessary to add it in a range of 0.1 to 1 part by volume.

If it is less than 0.1%, the effect is not sufficient, and if it is more than 10%, it is not necessary.

As the photosensitizer to be added, commonly used ones such as benzoin, benzoin ethers, benzophenone, tertiary amines, and benzyl are sufficient. The resin composition of the present invention can be cured by photocuring, because photocuring can cure the resin in a very short time, and it is a significant energy saver compared to conventional heat curing, and is also promising in terms of preventing environmental pollution. Particularly advantageous is its use in coatings.
However, other than photocuring, curing can also be carried out at room temperature or by heating, and as a catalyst for curing at room temperature or heating, commonly used organic peroxide catalysts such as ketone peroxides, hydroperoxides, azo compounds, etc. Azobisisobutyronitrile and the like can also be effectively used. The present invention can further contain dyes and pigments, fillers, and reinforcing materials within the range that do not interfere with curing.

The resin composition according to the invention can be used, for example, for coating metal products, stone, bricks, roof tiles, cement products, plaster products, pottery, porcelain, pottery, slate products, calcium silicate plates, inorganic glass products, in particular Painting stone, cement products, plaster products, and slate products can give them an appearance similar to stone, and painting wood products can give a high-quality wood product finish. Furthermore, it is very useful for coating plastics to increase the surface hardness, such as coating FRP, coating plastic lenses, and coating salt pepper floor tiles. Example 1 212 g of diarylidene pentaerythritol (same purity of 99% or less), 174 y of 2-hydroxyethyl acrylate, 1 y of baratoluenesulfonic acid, 0.12 q of hydroquinone were placed in an 11 three-meter flask equipped with a thermometer, a reflux condenser, and a stirrer. After charging and stirring at 80 to 90°C for 4 hours, infrared analysis determined that 98% of the hydroxyl groups had reacted.

Next, 70 f of benzyl alcohol was added and the reaction was continued for an additional 2 hours. After washing the reaction product with warm water of pH 8, add 6V of dimethylaminoethanol as a stabilizer and add 3 to 5
Volatiles were removed under reduced pressure of TfnHg. The obtained cycloacetal acrylate (4) was a pale brown liquid with a viscosity of 3.4 poise. Separately, one with a similar device
e Add Epicoat 8 as an epoxy resin to the Mitsuro flask.
27 (Shell Chemical Bisphenol A epoxy resin, epoxy equivalent 187) 350g, acrylic acid 10
8f1 methacrylic acid 43y1 diethylamine hydrochloride 1.
Add 0.2f of 5q1 hydroquinone and heat to 120-130℃
After reacting for 4 hours, the acid value became 2.4. The obtained epoxy-acrylate (B) was light brown in color and had a viscosity of about 1500 poise (molecular weight about 501). 2 parts of benzophenone was added to 10 parts of the mixed resin of both, and the mixture was coated on a glass plate to a thickness of 200 μm using a percoater, and its physical properties were examined. As shown in Table 1 below, the effects of combined use were observed.
In the batch test of 1 ha α agricultural degree on the human body, all of them were 2
A slight red rash was observed after 4 hours, but it disappeared within 2 to 3 days.

However, when trimethylolpropane triacrylate (reported to have a rabbit test value of 1.53) is used instead of cycloacetal acrylate (4), 111
Even at a temperature of 0, red spots appeared all over the body, and one out of three patients had blisters. Example 2 Diarylidenepentaerythrite 212y was placed in a 1e three-meter flask equipped with a stirrer, a thermometer, and a reflux condenser.
12-hydroxypropyl acrylate 194y1 Valatoluenesulfonic acid 1.2y1 Hydroxynon 0.11
1, heated at 85-90℃ for 3 hours, and stirred.
As a result of infrared analysis, it was determined that most of the free hydroxyl groups had disappeared.

Next, 50 y of n-butanol was added and the reaction was continued for another 2 hours, then 1 da of diethylamine was added and stirred for 3 min.
Unreacted butanol was removed under reduced pressure of ~3 mnHg. The obtained cycloacetal acrylate (C) was a pale yellowish brown liquid with a viscosity of 2.9 poise (25°C). Separately, in a 1' three-way flask equipped with a stirrer, a thermometer, and a fractionating condenser, add 134y1 of trimethylolpropane, 74yy of phthalic anhydride, 350y1 of acrylic acid, 0.25q1 of hydroquinone, 10ppm of copper naphthenate, 100% of toluene.
By preparing 6y of balatoluenesulfonic acid, the boiling point of toluene is 1eB! After proceeding with the esterification between f, toluene and free acrylic acid were mixed at normal pressure and then at
7! After Hg is distilled off under reduced pressure, it is dissolved again in 100 cc of toluene and washed twice with dilute soda solution.

After washing, toluene was distilled off again to obtain polyester acrylate (D) (molecular weight 580) in the form of a pale reddish brown syrup. If both are used together, as shown in Table 2,
It was one of the most effective methods for improving workability and physical properties. In the batch test of 1 ha α agricultural degree, there was no abnormality in 1 turbidity, and 2
Slight occurrence of red hem was observed in 3 out of 5 patients after 4 hours.

Example 3 430y of methacrylic acid, 148d of phthalic anhydride, 15y of triphenylphosphine, 0.3q of hydroquinone were placed in a 2F four-way flask equipped with a stirrer, a thermometer, a reflux condenser, and a dropping load, and 440y of propylene oxide was added dropwise at a temperature of 100°C. do.

After the dropwise addition was completed, the reaction was continued for 3 hours, and the reaction was stopped when reflux of propylene oxide was hardly observed. The acid value has decreased to 5 or less. Ethyl acetate 200y1
After adding 200 y of trimethylolpropane triacrylate and dissolving it uniformly, 588 g of hexamethylene diisocyanate was added and the reaction was continued at 80°C for 3 hours. As a result of infrared analysis, it was observed that most of the free hydroxyl groups had disappeared. Unsaturated acrylic urethane (E) (molecular weight 58
4) was obtained as a light reddish brown viscous liquid.

Separately, a 1' unit equipped with a stirrer, thermometer, and reflux condenser
Diarylidenepentaerythritol 2 in the Mitsuro flask
12y1 Trimethylolpropane diacrylate (purity approximately 92%, the remainder contains approximately the same amount of mono- and triacrylate) 222y1 Cyclohexanol 100q1 Valatoluenesulfonic acid 1.5y1 Hydroquinone 0.2y were charged and heated at 90°C for 4 hours. Upon stirring, infrared analysis revealed that most of the free hydroxyl groups disappeared.

The obtained cycloacetal acrylate (F) was light reddish brown in color and had a viscosity of 5.4 poise. 1 (1) part of the mixed resin of the above acrylic urethane (E) and cycloacetal acrylate (F), 3 parts of titanium white, 1 part of benzophenone,
Add 1 part of dimethylaminoethanol, paint to a thickness of 200μ on a Bonderite steel plate, and use a mercury lamp with an output of 2KW.
It was irradiated at 5 cm. The results are shown in Table 3, and the effect of combined use was recognized. In the batch test of 1Ha α agricultural degree, unsaturated acrylic urethane (E) 100 (%) and 85%,
Other than the occurrence of red spots after 24 hours, only a slight tendency was observed, and it was confirmed that the product was highly safe.

Example 4 In a 1e three-turn flask equipped with a stirrer, a thermometer, and a reflux condenser, 7 moles of ethylene glycol, 3 moles of diethylene glycol, and 5 moles of methyltetrahydrophthalic anhydride having a molecular weight of about 130 and 96% of the terminal groups being carboxyl groups, Carboxyl polyester synthesized from 5 moles of phthalic anhydride 420 da, glycidyl methacrylate 95 da
q1 trimethylbenzylammonium chloride 1.2g
, add 0.2y of hydroquinone, and heat to 120-130°C.
After reacting for 5 hours, the acid value became 9.9.

At the end of the reaction, 100 V of trimethylolpropane trimethacrylate was added. The obtained polyester acrylate (G) (molecular weight approximately 1,600) was in the form of a pale reddish brown syrup. Separately, in a 1e three-meter flask equipped with a stirrer, thermometer, and reflux condenser, diarylidenepentaerythritol 212y12-hydroxyethyl acrylate 18
6q1 linseed oil fatty acid diglyceride 120y1 balatoluene sulfonic acid 1.5V1 hydroquinone 0.2y were charged and reacted at 80 to 90°C for 5 hours. As a result of infrared analysis, it was determined that 80% of the free hydroxyl groups had disappeared.

The obtained cycloacetal acrylate (H) was reddish brown and had a viscosity of 8.8 poise. When a 100μ thick coating film was cured using a percoater under a 2KW output mercury lamp at a distance of 15C7I, polyester acrylate (G) alone became a gel in 5 minutes, and the unsaturated cycloacetal Acrylate (H) requires about 208', and what is its hardness? It was moderately hot.

A mixed resin containing 5% by weight of both gelled in 9 to W seconds and cured in 2 seconds, and its hardness was old. In a batch test of one batch, cycloacetal acrylate (H) and a mixed resin of 50% each showed slight red staining after 24 hours, and were judged to be highly safe, but polyester acrylate (G) Hay) In some cases, a condition similar to that of red spots was observed. Example 5 Triarylidene sorbitol (purity 86%) was added to a 1' three-way flask equipped with a thermometer, reflux condenser, and stirrer.
350q1 pentaerythritol triacrylate 200
y1 2-Hydroxypropyl acrylate 130y and isononyl alcohol 48f1 Valatoluenesulfonic acid 1.8y1 Hydroquinone 0.24y were charged and heated to 80°C.
After reacting at ~90°C for 5 hours, infrared analysis determined that approximately 90% of the free hydroxyl groups had reacted.

The obtained cycloacetal acrylate (1) was a reddish brown liquid with a viscosity of about 6 poise. When mixed with dipentaerythritol polyacrylate (mixture of esterification degree of 4 to 6 (molecular weight approximately 580)) and its physical properties were investigated, the fourth
As shown in the table, the effect of the combination was observed.

In a batch test using 1-ha alpha yield, a slight red rash was observed after 24 hours in all cases, but it disappeared within 2 to 3 days.

The rapid skin irritation value was 0.5 to 0.7, and it was judged to be highly safe. Example 6 To 1 mol of diarylidene pentaerythritide, (a) 1.2 mol of 2-hydroxyethyl acrylate and 0.8 mol of saturated alcohol, (
b) 1.5 moles of 2-hydroxyethyl acrylate and 0.5 moles of saturated alcohol; (c) 1.8 moles of 2-
The respective combinations of hydroxyethyl acrylate, 0.2 mol of saturated alcohol, and (d) 2.0 mol of 2-hydroxyethyl acrylate were reacted under the same reaction conditions as in Example 1 to synthesize unsaturated cycloacetal acrylate. did.

The changes in physical properties due to changes in the type and amount of saturated alcohol are shown in Table 5, and it is clear that the changes occur over a wide range.

Claims (1)

[Claims] 1 (A) (1) an unsaturated alcohol or a mixed alcohol thereof containing at least one acryloyl group or methacryloyl group and a hydroxyl group in the same molecule, (2) a saturated alcohol, (3) 1 A cycloacetal-acrylate containing one or more acryloyl groups or methacryloyl groups, or both thereof, obtained by reacting with a cycloacetal having one or more allyl ether type unsaturated bonds in the molecule, or a mixture thereof. , (B) an oligomer or polymer containing at least two or more of acryloyl groups and methacryloyl groups in one molecule, or a mixture thereof.