JPH0621235B2 - Active energy ray curable coating agent - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION "Object of the Invention" (Industrial field of application) The present invention relates to an active energy ray-curable coating material, and more specifically, it is cured by irradiation with ultraviolet rays or electron beams, and printing The present invention relates to an active energy ray-curable coating material having excellent suitability, coating suitability, workability such as adhesion to a base material and bending property.

(Prior Art) In recent years, active energy ray curable coatings have been extensively researched, and among them, practical application is progressing in the fields of printing inks, clear varnishes, paints, adhesives, photoresists and the like. There is. These are radically polymerizable monomers and prepolymers having radically polymerizable properties,
If necessary, it comprises a radical polymerizable initiator and a pigment, alkyd acrylate, polyester acrylate, epoxy acrylate, urethane modified acrylate, etc. as the prepolymer, and bisphenol A alkylene oxide adduct diacrylate, neo as the monomer. Pentyl glycol diacrylate, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, dipentaerythritol hexaacrylate, alkylphenol alkylene oxide adduct monoacrylate, etc. have been used.

However, when a curable coating agent using these compounds is used for printing ink, for example, a transfer failure often occurs due to stains during printing and emulsification of the ink. Furthermore, since it is cured instantaneously by irradiation with active energy rays, internal stress is likely to occur in the coating after curing. For this reason, when these curable coating agents are used as printing inks, paints, etc., they are printed or painted on the objects to be printed, such as metal or plastic,
The adhesiveness after curing is poor, and cracks tend to occur when bent due to the molding process. Therefore, the reality is that the range of application of these curable coatings is narrowed.

"Structure of Invention" (Means for Solving Problems) The present invention has been made as a result of intensive research to improve these drawbacks.
We have invented an active energy ray-curable coating agent that is excellent in curability, printability and coating suitability, and also has excellent workability such as adhesion to substrates and bendability.

That is, the present invention, (A) a polyol and a divalent carboxylic acid anhydride, the ratio of the valence of the hydroxyl group of the polyol and the number of moles of the divalent carboxylic acid anhydride is reacted at 0.9 to 1.1 A prepolymer obtained by subjecting a half-esterified product to an esterification reaction of a polyol and a monovalent carboxylic acid having no radical polymerizable double bond, and then subjecting a monovalent carboxylic acid having a radical polymerizable double bond to an esterification reaction, and And (B) a monomer having a radical-polymerizable double bond, which is an active energy ray-curable coating agent.

As the polyol used in (A) according to the present invention,
Compounds having two or more hydroxyl groups, such as ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, butylene glycol, pentyl glycol, neopentyl glycol, Hexanediol, glycerin, diglycerin,
Trimethylolpropane, ditrimethylolpropane,
Trimethylolethane, ditrimethylolethane, tetramethylolmethane, dipentaerythritol, polycyclopentadiene diallyl alcohol copolymer, spiroglycol, bisphenol A ethylene oxide adduct, bisphenol A propylene oxide adduct,
Bisphenol F ethylene oxide adduct, bisphenol F propylene oxide adduct (the number of moles of alkylene oxide added is usually 1 to 2 moles per 1 hydroxyl group of bisphenol), water-added bisphenol A, water-added bisphenol F, etc. is there.

In addition, the addition of alkylene oxide to bisphenols was carried out by charging bisphenols and about 0.5% by weight of sodium hydroxide as a catalyst (based on the total amount including alkylene oxide) into the autoclave, and gradually adding alkylene oxide. Charge, 160 ℃, 5kg / c
m ² was reacted in the following, an end point at a gauge pressure of 0.1 kg / cm ² or less.

Examples of the divalent carboxylic acid anhydride include aliphatic carboxylic acid anhydrides such as oxalic acid, malonic acid, succinic acid, alkyl or alkenyl succinic acid, glutaric acid and maleic acid, o- (water-added) phthalic acid, hymic acid. An alicyclic or aromatic carboxylic acid anhydride such as acid, methylhymic acid, diphenic acid, or naphthalic acid is used.

The reaction between the polyol and the carboxylic acid anhydride is mainly a half-ester reaction, and the half-ester reaction is, for example, in a 4-necked flask equipped with a stirrer at 100 to 200 ° C, preferably 130 to 170 ° C and 0.5 to several. Done in time. Further, the reaction is carried out under a stream of an inert gas such as nitrogen gas or carbon gas, and a reaction solvent may be used if necessary.

As for the reaction amount ratio number of the polyol and the divalent carboxylic acid anhydride, it is desirable that the ratio of the valence number of the hydroxyl group of the polyol and the number of moles of the divalent carboxylic acid anhydride is 0.9 to 1.1.

The esterification reaction of the half-esterified product containing a carboxyl group with a polyol and a monovalent carboxylic acid having no radical-polymerizable double bond, even if the polyol and the monovalent carboxylic acid are simultaneously reacted with the half-esterified product, or The half-esterified product may be reacted with a polyol first, and then with a monovalent carboxylic acid.

The reaction between the carboxyl group-containing compound generated by the half-ester reaction and the polyhydroxyl compound is, for example, 170
-300 degreeC, Preferably it carries out between 180-260 degreeC. As for the reaction amount ratio between the half-esterified product and the polyhydroxyl compound, it is desirable that the ratio between the valence of the carboxyl group of the half-esterified product and the number of moles of the polyol is 0.9 to 1.1. Further, the hydroxyl group-containing compound generated by the above reaction is reacted with a monovalent carboxylic acid having no radically polymerizable double bond (may be simultaneously reacted with the polyol). The reaction between the hydroxyl group-containing compound and the monovalent carboxylic acid having no radically polymerizable unsaturated double bond is 170 to 30.
It is carried out at 0 ° C, preferably between 180 and 260 ° C. This reaction may be carried out simultaneously with the reaction of the carboxyl group-containing compound generated by the above-mentioned half ester reaction and the polyhydroxyl compound.

As monovalent carboxylic acids having no radical-polymerizable double bond, formic acid, acetic acid, propionic acid, butyric acid, valeric acid, trimethylacetic acid, caproic acid, n-heptanoic acid, caprylic acid, pelargonic acid, methoxyacetic acid, coconut oil Aliphatic carboxylic acids such as fatty acids, palmitic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, benzoic acid, alkylbenzoic acid, alkylaminobenzoic acid, phenylacetic acid, halogenated benzoic acid, anisic acid, benzoylbenzoic acid, There are aromatic carboxylic acids such as naphthoic acid, rosin, and water-added rosin. Further, there is an esterified product of the above-mentioned divalent carboxylic acid and an esterified product in which a monohydric alcohol or one alcoholic hydroxyl group remains.

The monohydric alcohols include methyl alcohol, ethyl alcohol, propyl alcohol, allyl alcohol, butyl alcohol, amyl alcohol, hexyl alcohol, octyl alcohol, capryl alcohol,
Decyl alcohol, lauryl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol and other aliphatic alcohols, benzyl alcohol, phenol, alkylphenol alkylene oxide adducts, and other aromatic alcohols, cyclohexanol, rosin alcohol, water-added rosin alcohol, etc. Can be mentioned. The esterified product having one alcoholic hydroxyl group left is an esterified product with the monovalent carboxylic acid described above.

Next, after cooling to a reaction product of a carboxyl group-containing compound and a polyhydroxyl compound produced by the half-ester reaction or a reaction product of the reaction product and a monovalent carboxylic acid having no radical-polymerizable double bond, the radical-polymerizable dicarboxylic acid A monovalent carboxylic acid having a heavy bond is charged and the reaction is carried out at a reaction temperature of 80 to 115 ° C. while blowing air. Hydrochloric acid, sulfuric acid, p-toluenesulfonic acid and the like are used as the reaction catalyst, and hydroquinone, metoquinone and the like are used as the polymerization inhibitor.

Examples of the monovalent carboxylic acid having a radical-polymerizable double bond include (meth) acrylic acid, crotonic acid, vinyl acetic acid and cinnamic acid. Acrylic acid is preferred for printing inks and paints that normally require fast curability.

The coating agent of the present invention contains, in addition to the prepolymer and (A), one or more other prepolymers or monomers (B) having a radically polymerizable double bond, if necessary.
The monomers include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, allyl (meth) acrylate, butyl (meth) acrylate, amyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth). Acrylate, capryl (meth) acrylate, decyl (meth) acrylate, lauryl (meth) acrylate, myristyl (meth) acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, benzyl (meth) acrylate, alkylene oxide addition of alkylphenol Examples thereof include monofunctional monomers such as (meth) acrylate and cyclohexyl (meth) acrylate. Further, as a bifunctional or higher functional monomer, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, polyethylene glycol di (meth)
Acrylate, propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, butylene glycol di (meth) acrylate, pentyl glycol (meth) Acrylate, neopentyl glycol di (meth) acrylate, hydroxypiparyl hydroxypivalate di (meth) acrylate, hexanediol di (meth) acrylate, (di) glycerin tri (meth) acrylate, diglycerin alkylene oxide tetra (meth) acrylate , Trimethylolpropane tri (meth) acrylate, trimethylolpropane alkylene oxide tri (meth) acrylate, ditrimethylolpropane Pantetra (meth) acrylate, ditrimethylolpropane alkylene oxide tetra (meth) acrylate, trimethylolethane tri (meth) acrylate, ditrimethylolethane tri (meth) acrylate, trimethylolethane alkylene oxide tri (meth) acrylate, ditrimethylolethane alkylene Oxide tetro (meth) acrylate, tetramethylolmethane tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, bisphenol A alkylene oxide di (meth) acrylate, bisphenol F alkylene oxide di (meth) acrylate, dihydroxybenzene alkylene oxide di (Meth) acrylate, trihydroxybenzene alkylene oxide di ( Data) acrylate, hydrogenated bisphenol A di (meth) acrylate, hydrogenated bisphenol F di (meth) acrylate,
Examples thereof include water-added bisphenol A alkylene oxide adduct di (meth) acrylate and water-added bisphenol F alkylene oxide adduct di (meth) acrylate. Other examples include lactone adduct monomers. That is, polyethylene glycol polylactonate di (meth) acrylate, polypropylene glycol polylactonate di (meth) acrylate, alkylene glycol polylactonate di (meth) acrylate, glycerin polylactonate tri (meth) acrylate, diglycerin polylactonate Tetra (meta)
Acrylate, trimethylolpropane polylactonate tri (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, pentaerythritol polylactonate tetra (meth) acrylate, dipentaerythritol polylactonate hexaacrylate, and other polyol lactonate polyacrylates Is. The lactone of the above monomer is a compound containing in the ring a functional group —CO—O— of an ester such as γ-butyrolactone 8-valerolactone and ε-caprolactone.

In the use of the coating agent of the present invention, when the active energy ray is ultraviolet light, it is necessary to add a photosensitizer, that is, a radical polymerization initiator (also a radical polymerization accelerator) (C), benzoin, benzoin Benzoin sensitizers such as methyl ether, benzoin ethyl ether, benzoin isopropyl ether, α-acrylbenzoin,
Benzophenone, p-methylbenzophenone, p-chlorobenzophenone, tetrachlorobenzophenone, o-
Aryl ketone sensitizers such as methyl benzoylbenzoate and acetophenone, 4,4-bisdiethylaminobenzophenone, isoamyl p-dimethylaminobenzoate, p
Examples thereof include dialkylaminoarylketone-type sensitizers such as dimethylaminoacetophenone, and polycyclic carbonyl-type sensitizers such as thioxanthone, xanthone and halogen substitution products thereof, and these may be used alone or in an appropriate combination. These photosensitizers are contained in the composition at 1 to
Although it can be used in the range of 30% by weight, it is preferably in the range of 0 to 15% by weight.

To prepare an active energy ray-curable ink composition, a pigment is usually dispersed in the above-mentioned diluted varnish, but this method is not particularly limited, and it can be carried out by a conventional dispersion method such as three rolls or ball mill. it can. In addition to organic, inorganic, and extender pigments, a plasticizer, a surfactant, a thermal polymerization inhibitor, etc. can be added if necessary. Of course, there may be an ink composition containing no pigment. Further, other resins may be used in combination within the range that does not impair the effects of the present invention.

The present invention will be described below with reference to specific examples. All parts in the examples are parts by weight.

Production Example 1 Epicoat 828 (epoxy resin made by Shell Chemical) 71.7
Parts, acrylic acid 28.3 parts, triethylenediamine 0.1 parts,
Hydroquinone (0.1 part) was placed in a 4-necked flask equipped with a stirrer and reacted at 100 ° C while blowing air to about 15
After an hour, when the acid value became 1 or less, it was pumped out. The obtained radically polymerizable prepolymer is referred to as prepolymer a.

Production Example 2 Charge 31.6 parts of trimethylolpropane, 33.5 parts of nonyl acid, and 5 parts of xylol to a 4-neck flask and react under a nitrogen gas stream at 200 ° C until the acid value becomes 5, and then add 19.6 parts of isophthalic acid. The reaction was carried out at 230 ° C. for 10 hours, and when the acid value reached 10, the solvent was removed and the mixture was cooled to 100 ° C. Further, 5 parts of cycloxane, 0.1 part of hydroquinone and 1 part of p-toluenesulfonic acid were charged, and while blowing air, 15.3 parts of acrylic acid was charged with the dropping funnel over about 1 hour. At 100 ° C, after 15 hours, the acid value was 5.5. So I removed the solvent and pumped it out. This is designated as prepolymer b.

Production Example 3 900 parts of Epicoat 1001 (epoxy resin manufactured by Shell Chemical Co., Ltd.), 363 parts of benzoic acid, 1 part of triethylenediamine, and 100 parts of xylol were charged into a 4-neck flask equipped with a stirrer, and under a nitrogen gas stream, 150 ° C. The reaction was carried out for 1 hour at 220 ° C. for 5 hours, and when the acid value reached 5.5, it was pumped out. This is designated as prepolymer c.

Production Example 4 trimethylolpropane (trivalent) 134 parts (1 mol),
Tetrahydrophthalic anhydride 486 parts (3.2 mol) and xylol 50 parts are charged into a 4-necked flask equipped with a stirrer, and reacted at 150 ° C. for 1 hour under a nitrogen gas stream. Charge 402 parts of trimethylolpropane, 280 parts of oleic acid, and 384 parts of benzoylbenzoic acid, and gradually raise the temperature to 240 ° C.
After reacting for 8 hours, the acid value became 5.5. Then, after desolvation and cooling, 100 parts of cyclohexane, 1 part of hydroquinone, 10 parts of p-toluenesulfonic acid and 195 parts of acrylic acid were charged at 80 ° C., and at 100 ° C. while blowing air,
After reacting for 7 hours, the acid value became 13.5, so the solvent was removed and pumped out. This is designated as prepolymer d.

Production Example 5 Glycerin (trivalent) 92 parts (1 mol), phthalic anhydride 4
74 parts (3.2 mol) and 50 parts of xylol were placed in a 4-necked flask equipped with a stirrer, and the mixture was stirred at 150 ° C. under a nitrogen gas stream for 1 hour.
React for hours. Next, 408 parts of pentaerythritol,
Charged 1485 parts of water-added rosin and gradually raised the temperature to 240
The acid value became 5 by reacting at 8 ° C. for 8 hours. After removing the solvent, the mixture was cooled, and at 80 ° C., 200 parts of cyclohexane, 2 parts of hydroquinone, 20 parts of p-toluenesulfonic acid, 2 parts of acrylic acid.
60 parts were charged and reacted at 100 ° C. for 7 hours while blowing air, and the acid value became 14.0. Therefore, the solvent was removed and the solution was pumped out. This is designated as prepolymer e.

Production Example 6 Pentaerythritol (tetravalent) 136 parts (1 mol), methylhymic acid anhydride 712 parts (4 mol), and xylol 75 parts were charged into a 4-necked flask equipped with a stirrer, and under a nitrogen gas stream at 150 ° C., Let react for 1 hour. Next, 416 parts of neobenthyl glycol and 480 parts of p-t-butylbenzoic acid were charged, the temperature was gradually raised, and the reaction was carried out at 240 ° C for 8 hours to give an acid value of 5.6. Next, after removing the solvent, the mixture was cooled, and at 80 ° C, 150 parts of cyclohexane, 1.5 parts of hydroquinone, p-
15 parts of toluenesulfonic acid and 65 parts of acrylic acid were charged and reacted at 100 ° C. for 7 hours while blowing air, and the acid value became 12.9, so the solvent was removed and the product was pumped out. This is designated as prepolymer f.

Next, using the prepolymer and monomer etc. made in the production example,
An active energy ray curable coating material was prepared. Table 1 below
Note.

Example 1 The coating compositions (printing inks) shown in Table 1 and Comparative Samples 1, 2, 3 and Example Samples 5 to 7 were printed by KORD Heidelberg to stain non-image areas during printing and water. The width (Note-2) was measured (Table-2).

Example 2 Next, the active energy ray-curable coating material shown in Table 1 was added to T
Samples 1, 2, 3, 5 and 7 were coated on the FS board with alkyd resin, epoxyphenol resin, and acrylic resin paints.
Print with a coating amount of 0 mg / 100 cm ² and for samples 4 and 9, 70 mg / 100 cm ^{2 on} each coated plate with a bar coater.
The coating amount was Samples 1, 2, 3, 5 in Table-3
For ~ 7, a high-pressure mercury lamp with an intensity of 80 W / cm 2
The place 10 cm below the lamp was placed on a conveyor, irradiated and cured.

The samples 4 and 8 were cured by irradiation with 10 Mrad using a curtain beam type electron irradiation device. The results of the adhesion of each coating film obtained are shown in Table 3 below.

"Effects of the Invention" The active energy ray-curable coating material of the present invention has a better printing effect as shown in the examples as compared with the conventionally known coating compositions, and further has excellent adhesiveness and active energy rays. The application range of the curable coating agent can be expanded.

Claims (1)

[Claims] 1. A half ester obtained by reacting (A) a polyol and a divalent carboxylic acid anhydride at a ratio of the valency of the hydroxyl group of the polyol to the number of moles of the divalent carboxylic acid anhydride of 0.9 to 1.1. Prepolymer obtained by subjecting the compound to an esterification reaction of a polyol and a monovalent carboxylic acid having no radical polymerizable double bond, and then subjecting a monovalent carboxylic acid having a radical polymerizable double bond to an esterification reaction, and ( B) An active energy ray-curable coating material comprising a monomer having a radical-polymerizable double bond.