JPH0254366B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a photocurable resin that is easily cured by light and is mainly used as a binder for photocurable printing inks, but can also be used as a binder for photocurable paints. . Conventional photocurable printing inks include epoxy acrylate resin, urethane acrylate resin, and polyester acrylate resin. In particular, epoxy acrylate resin contains reactive diluents, photosensitizers, and pigments as main components, and other additives as necessary. Compositions containing additives are generally known. Compared to conventional solvent-based printing inks, this type of printing ink has the following advantages: there is no problem of environmental pollution due to organic solvent volatilization, the ink does not dry on the printing press, and productivity can be improved by high-speed printing. It has the following advantages. However, on the other hand, it tends to polymerize and turn into a gel, resulting in poor storage stability, poor wettability with pigments, poor gloss, and especially in the case of offset printing, because the ink is highly hydrophilic and has poor emulsion resistance. It has not been able to replace solvent-based printing inks because it has many drawbacks, such as poor gloss and sharpness, and difficulty in cleaning printing press rolls with aliphatic hydrocarbon solvents. JP-A No. 54-118499 discloses a photocurable resin obtained by reacting a rosin-modified unsaturated resin ester with a metal alkoxide, which overcomes the drawbacks of conventional photocurable resins. but,
Since this resin uses epoxy resin for its resin skeleton, it has many hydroxyl groups with strong hydrophilic properties.
It has the disadvantage of poor solubility in aliphatic hydrocarbons. In view of the above circumstances, it is an object of the present invention to provide a photocurable printing ink binder that has good storage stability, good gloss and clearness, and is easy to clean with aliphatic hydrocarbons. An object of the present invention is to provide a method for producing a photocurable resin that can also be used as a binder. The method for producing the photocurable resin of the present invention includes (1) 100 parts by weight of a disproportionate rosin having an abietic acid content of 1% or less (based on weight, the same applies hereinafter), (2) 20 to 100 parts by weight of polyvalent isocyanate. , (2) polyfunctional alcohols 10~
By reacting the polymerizable unsaturated groups with 60 parts by weight, a disproportionate rosin-modified urethanized unsaturated product having one or more polymerizable unsaturated groups per molecule and a hydroxyl value of 80 or less. This is a method for producing a photocurable resin made of a saturated resin. However, if necessary, reaction diluents, such as (meth)acryloyl compounds (representing methacryloyl compounds and/or acryloyl compounds), vinyl group-containing compounds, can also be added. In the present invention, the disproportionated rosin refers to a modified rosin obtained by subjecting rosin to a disproportionation reaction mainly with abietic acids using a catalyst such as iodine, sulfur, or selenium at a temperature of 200°C or higher. Stability is increased by reducing the number of conjugated double bonds. The reason why the degree of disproportionation was indicated by the abietic acid content is that isomers with conjugated double bonds, such as parastric acid and neoabietic acid, change to abietic acid during disproportionation. It is. The reason for including the disproportionate rosin in the photocurable resin obtained by the present invention is that the presence of this rosin improves the storage stability of the photocurable resin without impairing the photocurability, and improves the pigment resistance. This is because it exhibits excellent effects such as improved gloss due to its high affinity, improved emulsification resistance due to its strong hydrophobicity, and improved roll cleanability due to its high solubility in aliphatic hydrocarbons. . In addition, the use of 20 to 100% by weight of polyvalent isocyanate is due to the formation of urethane bonds, which increases flexibility, and the reduction or disappearance of highly hydrophilic hydroxyl groups, which improves emulsification resistance and aliphatic hydrocarbons. This is because it has effects such as improving solubility in solvents. The polyvalent isocyanate used in the present invention is, for example, tolylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, xylidene diisocyanate, naphthalene diisocyanate, polymers of various diisocyanates, combinations of the above polyvalent isocyanates and active hydrogen compounds, etc. Di- or polyisocyanates such as adducts. When the polyvalent isocyanate is less than 20 parts by weight, the urethane component decreases and the hydroxyl value increases, resulting in a decrease in curability and emulsification resistance, and when it is more than 100 parts by weight, the viscosity increases, This is undesirable because it causes gelation. Polyfunctional alcohols include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, allyl alcohol, ethylene glycol, propylene glycol, diethylene glycol, 1,3-butylene glycol, 1.6-hexanediol, and neopentane. Diol, glycerin, trimethylolpropane, trimethylolethane, pentaerythritol, dipentaerythritol, etc. contain one or more alcoholic hydroxyl groups in one molecule, and if there is one alcoholic hydroxyl group, a triple bond (meta) It has a functional group such as an acryloyl group. In the present invention, epoxy group-containing compounds having one or more hydroxyl groups and glycidyl groups in one molecule, such as glycidyl (meth)acrylate, bisphenol A diglycidyl ether, condensates thereof, alkylphenol di Glycidyl ether, alkylene glycol diglycidyl ether, versatile acid glycidyl ester, dimer acid glycidyl ester, epoxidized oil, epoxidized polybutadiene, etc. are also included in the above polyfunctional alcohols because they have both a hydroxyl group and a glycidyl group. . The amount of alcohol component used above is based on the photocurable resin.
A suitable amount is 10 to 60 parts by weight. In the present invention, in addition to the disproportionated rosin, non-resin carboxylic acids such as benzoic acid, p-tert-butylbenzoic acid, 0-benzoylbenzoic acid, succinic anhydride,
Adipic acid, sebacic acid, phthalic anhydride, isophthalic acid, tetrahydrophthalic anhydride, trimellitic anhydride, various vegetable oil fatty acids and their polymers dimer acid, maleic anhydride, fumaric acid, itaconic acid, (meth)acrylic acid, etc. A monobasic acid or a dibasic acid may be used as a component. All of these non-resin carboxylic acids can undergo an esterification reaction, and among these, dibasic acids have the effect of bonding with two hydroxyl groups and linking atomic groups through ester bonds. The above-mentioned asymmetric rosin, non-resin carboxylic acid, isocyanate, and polyfunctional alcohol mutually undergo a chemical reaction and bond. At this time, the constituent carboxylic acid of the asymmetric rosin and the non-resin carboxylic acid or The constituent carboxylic acids of the disproportionated rosin react with hydroxyl groups to form ester bonds, and the isocyanate groups of polyvalent isocyanates react with active hydrogen,
It mainly reacts with the active hydrogen of the hydroxyl group to form a urethane bond.
Alternatively, it can be easily obtained by sequentially esterifying and then carrying out a urethanization reaction with isocyanates. Next, it is obvious that in order to cause curing by light, each molecule must have at least one polymerizable unsaturated group. Further, the reason why the hydroxyl value is set to be 80 or less is because if it is 80 or more, emulsification resistance is poor and solubility in aliphatic hydrocarbon solvents is decreased. It is desirable to adjust the working viscosity, curability, properties of the cured film, etc. of the photocurable resin obtained by the present invention depending on the intended use. , polyhydric isocyanate, and polyfunctional alcohol, and the mixing ratio may be changed, but as mentioned above, a reactive diluent such as a (meth)acryloyl group-containing compound,
Substances having monofunctional or polyfunctional polymerizable unsaturated groups such as vinyl group-containing compounds can be added, but among these, (meth)acryloyl compounds are particularly preferred. To give an example of a (meth)acryloyl compound,
Methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, 2-
Ethylhexyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, butoxyethyl (meth)acrylate, glycidyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, ) Acrylate, (meth)acrylamide, ethylene glycol di(meth)acrylate, neopentanediol (meth)acrylate, 1.6−
Hexanediol di(meth)acrylate, diethylene glycol di(meth)acrylate, hydroxypivalic acid neopentanediol di(meth)acrylate, polyethylene glycol di(meth)acrylate, bisphenol di(oxyethyl) diether di(meth)acrylate,
Examples include trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, and dipentaerythritol hexa(meth)acrylate. In addition, when using ultraviolet rays as active light,
It goes without saying that it is advantageous to use known sensitizers such as benzoin-based, benzophenone-based, azo-based, and peroxide-based sensitizers as the photosensitizer. Example 1 300 parts (parts by weight, the same applies hereinafter) of tolylene diisocyanate (TDI-80) and 0.5 parts of dibutyltin dilaurate were placed in a four-necked flask equipped with a thermometer, a cooler, a gas blowing tube, and a stirrer. , heat to 60 °C under a stream of nitrogen gas. Next, hydroquinone 1
2-hydroxyethyl acrylate dissolved in
Drop 200 parts over 3 hours, keep at the same temperature for 2 hours,
Acrylated isocyanate () with NCO group% 13.8% was obtained. Next, in a four-necked flask with contents 1 equipped with a thermometer, gas blowing tube, stirrer, water separator, and condenser,
Disproportionate Rosin Bandice G- with abietic acid content of 0% and bihydroabietic acid content of 70%
263 parts of 100S (trade name, manufactured by Harima Kasei Kogyo Co., Ltd.), 25 parts of succinic anhydride, and 68 parts of pentaerythritol were reacted for 8 hours at 270°C under a nitrogen gas stream to form acid groups 6, and then heated at 100°C. The mixture was cooled to 60°C and 200 parts of butyl acetate was added thereto. To this, 145 parts of the acrylated isocyanate (1) described above was added over 1 hour, held at 60°C for 2 hours, heated, and reacted for 4 hours under refluxing butyl acetate.
After confirming the disappearance of the NCO group peak at 2250 cm ^-1 in the infrared spectrum, butyl acetate was distilled off under reduced pressure to obtain a photocurable resin (A) with an acid value of 4, a hydroxyl value of 33, and a softening point of 75°C. Obtained. Example 2 The same treatment as in Example 1 was carried out except that 140 parts of dimer acid (Versadime 216, manufactured by Henkel Japan Co., Ltd.) was used instead of 25 parts of succinic anhydride, and the acid value was 3 and the hydroxyl value was 28. A photocurable resin (B) having a softening point of 55°C was obtained. Example 3 174 parts of TDI-80 and 0.5 parts of dibutyltin dilaurate were charged into the same apparatus used to obtain acrylated isocyanate (1) in Example 1, and heated to 60°C under a nitrogen stream. Next, add 3 parts of 278 parts of pentaerythritol triacrylate in which 1 part of hydroquinone was dissolved.
Dropped at the same temperature for 2 hours, NCO group%
Acrylated isocyanate (2) of 8.8 was obtained. Next, among the raw materials used in Example 2, 145 parts of acrylated isocyanate (1) was replaced with 236 parts of acrylated cyanate (2), but the same process was carried out.
Photocurable resin with acid value 4, hydroxyl value 26, and softening point 62℃
I got (C). Example 4 Using the same equipment used to produce the photocurable resin (A) in Example 1, asymmetric rosin Bandeis G-100S263 was prepared.
After reacting at 270° C. for 8 hours under a nitrogen gas stream to give an acid value of 7, the mixture was cooled to 100° C., and 200 parts of butyl acetate was added to obtain composition (2). A mixture of 44 parts of TDI-80 and 145 parts of acrylated isocyanate (1) was added to this over 1 hour, and the mixture was heated to 60°C.
After holding for 2 hours, the temperature was raised and reaction was carried out under butyl acetate reflux for 4 hours. After confirming the disappearance of the NCO group peak (2250 cm ^-1 ) in the infrared spectrum, the butyl acetate was distilled off under reduced pressure to determine the acid value. 5. Hydroxyl value 33, softening point 82
A photocurable resin (D) at ℃ was obtained. Example 5 333 parts of isophorone dicyanate and 0.7 parts of dibutyltin laurate are charged into the same apparatus used to obtain acrylated isocyanate (1) in Example 1, and heated to 60°C under a nitrogen gas stream. Next, 174 parts of 2-hydroxyethyl acrylate in which 1 part of hydroquinone was dissolved was added dropwise over 3 hours, and the temperature was then kept at the same temperature for 2 hours to obtain an acrylated isocyanate (3) with an NCO group% of 12.2. Next, using the same equipment used to produce the photocurable resin in Example 1, the acrylated isocyanate (1) of Example 1 was prepared.
145 parts of the above acrylated isocyanate in place of
A photocurable resin (E) having an acid value of 5, a hydroxyl value of 33, and a softening point of 72°C was obtained by the same treatment except that 169 parts of the resin was used. Example 6 In the same apparatus used to produce the acrylated isocyanate in Example 1, 336 parts of hexamethylene diisocyanate and 0.8 parts of dibutyltin laurate were charged and heated to 60°C under a nitrogen gas stream. Next, 232 parts of 2-hydroxyethyl acrylate in which 1 part of hydroquinone was dissolved was added dropwise over 3 hours, and the temperature was then kept at the same temperature for 2 hours to obtain acrylated cyanate (4) with an NCO group percentage of 14.5. Next, in the same equipment used to obtain the photocurable resin (A) in Example 1, 145 parts of acrylated isocyanate (1) among the raw materials used in Example 1 was mixed with 142 parts of the above acrylated isocyanate (4). A photocurable resin (F) having an acid value of 4, a hydroxyl value of 33, and a softening point of 70° C. was obtained by the same treatment except that . Example 7 280 parts of Vandeith G-100S and epoxy equivalent were added to the same equipment used to make the photocurable resin (1) in Example 1.
190 epoxy resin Eport YD-128 (product name,
152 parts (manufactured by Toto Kasei Co., Ltd.) and 0.3 parts of tetramethylammonium chloride were heated at 170°C under a nitrogen gas stream.
After reacting for 2 hours to give an acid value of 1.5, the mixture was cooled to 100°C, and 200 parts of butyl acetate was added to bring the temperature to 60°C. Next, the acrylated isocyanate (1) shown in Example 1
209 parts were added over 1 hour, held at 60°C for 2 hours, heated, and reacted for 6 hours under refluxing butyl acetate. After confirming the disappearance of the NCO group peak (2250 cm ^-1 ) in an infrared spectrum, the mixture was heated under reduced pressure. Butyl acetate was distilled off to obtain a photocurable resin (G) having an acid value of 1, a hydroxyl value of 9, and a softening point of 70°C. Example 8 Asymmetric rosin Bandeis G-100S was added to the same equipment used to produce the photocurable resin (1) in Example 1.
After charging 350 parts and 136 parts of pentaerythritol and reacting at 280°C under a nitrogen gas stream for 5 hours to give an acid value of 5, the mixture was cooled to 110°C and diluted by adding 250 parts of toluene. Next, 108 parts of acrylic acid, 0.6 parts of hydroquinone, and 5 parts of p-toluenesulfonic acid were added, and the mixture was reacted for 15 hours under toluene reflux while blowing air to give an acid value of 7, and then cooled to 60°C. Furthermore, 87 parts of TDI-80 and 0.3 parts of dibutyltin dilaurate were added over 1 hour, and the mixture was reacted at the same temperature for 4 hours.
After confirming the disappearance of the NCO group (2250 cm ^-1 ), it was cooled, neutralized by adding 2 parts of potassium hydroxide, washed with water, and the volatile components were distilled off under reduced pressure.
℃ photocurable resin (H) was obtained. Example 9 Of the raw materials used in Example 1, an abietic acid content of 0.5% and a dehydroabietic acid content of 47
% disproportionate rosin, Bandes G-100, was used in place of the disproportionate rosin containing 0 abietic acid, and the acid value was 4.5.
A photocurable resin (I) having a hydroxyl value of 34 and a softening point of 73°C was obtained. Comparative Example Ratio 1 Among the raw materials used in Example 1, abietic acid content of 2.3% and dehydroabietic acid content of 2.3% and dehydroabietic acid content as asymmetric rosin were placed in the same equipment used to produce the photocurable resin (1) in Example 1. Except for using 41%
The same treatment as in Example 1 was carried out to obtain a photocurable resin (ratio A) having an acid value of 5, a hydroxyl value of 34, and a softening point of 74°C. Comparative Example Ratio 2 Among the raw materials used in Example 1, Bandeis G-100 was added to gum rosin (Class X produced in the People's Republic of China) in the same equipment used to produce the photocurable resin (1) in Example 1.
A photocurable resin (ratio B) having an acid value of 4.5, a hydroxyl value of 34, and a softening point of 73° C. was obtained by reacting in the same manner as in Example 1, except that . Comparative Example Ratio 3 In the same equipment used to produce the photocurable resin (1) in Example 1, 49 parts of disproportionated rosin bandice G-100S with 0 abietic acid content, 50 parts of succinic anhydride, and 134 parts of trimethylolpropane were added. After reacting for 6 hours at 250°C under a nitrogen gas stream to give an acid value of 2, the mixture was cooled to 100°C, 200 parts of butyl acetate was added, and the temperature was raised to 60°C. Next, 290 parts of the acrylated isocyanate (1) shown in Example 1 was added over 1 hour, and 60 parts of
After being kept at ℃ for 2 hours, the temperature was raised, and the reaction was carried out for 4 hours under refluxing butyl acetate.
After confirming that the peak of the group (2250 cm ^-1 ) disappeared, butyl acetate was distilled off under reduced pressure to obtain a photocurable resin (ratio C) having an acid value of 1.5, a hydroxyl value of 95, and a softening point of 70°C. Comparative Example Ratio 4 Among the raw materials used in Example (8), TDI-80 was added to the same equipment used to produce the photocurable resin (1) in Example 1.
The reaction was carried out in the same manner except that the amount was reduced to 26 parts, to obtain a photocurable resin (ratio D) having an acid value of 5, a hydroxyl value of 122, and a softening point of 45°C. The photocurable resins obtained in the above Examples and Comparative Examples were kneaded with three rolls in the formulations shown in Table 1, and the tack was 12 to 14 (Incometer B manufactured by Toyo Seiki Seisakusho).
-45 type), and performance tests were conducted as follows. 1 Curability Spread 0.2 cc of each test printing ink on art paper using a two-part roll of RI Tester (manufactured by Mei Seisakusho),
Immediately after color development, the ink film was placed on a variable speed conveyor and passed under an 80 W/cm high-pressure mercury lamp, and the curing time (seconds) was determined from the conveyor speed required for each color spread ink film to harden to the touch. 2 Gloss For the solid printed matter completely cured in the above ultraviolet curing test, use a gloss meter to measure the reflection angle.
The gloss value was measured and judged at 60°. The evaluation method was as follows: gloss value of 60 or more was ◎, 60-50 was ○, 50-40 was △, and 40 or less was ×. 3. Emulsification resistance It was determined by stirring a mixture of 70 parts of each test printing ink and 100 parts of dampening water at high speed, removing separated water, and measuring the amount of water emulsified in the ink. 4. Fluidity (Flow) Using a parallel plate viscometer, the radius (mm) of the ink spread after 1 minute was measured in a constant temperature room at 25°C. 【table】

Claims (1)

[Claims] 1 By reacting 100 parts by weight of a disproportionated rosin with an abietic acid content of 1% or less, 20 to 100 parts by weight of a polyvalent isocyanate, and 10 to 60 parts by weight of a polyfunctional alcohol, a polymerizable unsaturated group is formed per molecule. A method for producing a photocurable resin comprising a symmetric rosin-modified urethanized unsaturated resin having one or more hydroxyl groups and a hydroxyl value of 80 or less.