JPH06263811A - Photoinitiator composition and photo-curable coating composition - Google Patents

Abstract

PURPOSE:To obtain a photoinitiator composition which emits less odor during and after printing and a photo-curable coating composition which gives a cured film having high hardness and retaining good curability for a long time. CONSTITUTION:The photoinitiator composition is a product of the reaction of a hydroxylated amine or amino compound with dimethylaminobenzoic acid and/or benzoylbenzoic acid and has a mol.wt. of 300-2,000. The coating composition contains this photoinitiator composition.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a photoinitiator composition which is cured by ultraviolet irradiation and a photocurable coating composition containing the same.

[0002]

2. Description of the Related Art In recent years, research on photocurable coating compositions, in particular, curable coating compositions by ultraviolet rays has been vigorously carried out. Among them, printing inks, overcoat varnishes, paints, adhesives, photoresists, etc. It is being put to practical use in the field. These are photoinitiators, resins (including both radically polymerizable resins and non-radically polymerizable resins), radically polymerizable monomers, pigments (not included in overcoat varnish), additives, etc. Consists of. A commonly used photoinitiator is benzophenone such as methyl o-benzoylbenzoate, Darocur 11
73, Darocur 2959, Irgacure 184, Irgacure 907 (Irgacure and Darocur are trademarks of Ciba-Geigy), and the like, Irgacure 6
51 etc. benzoin-based, thioxanthone-based, EAB (Hodogaya Chemical Co., Ltd.), SEICOL PAA (Seiko Chemical Co., Ltd.),
A hydrogen donation system such as Kayakyu EPA (manufactured by Nippon Kayaku Co., Ltd.) is used. However, these photoinitiators have a molecular weight of 30.
When it is 0 or less, it has a sublimation property, so that it partially volatilizes and causes an odor of printing, a coating site, a printed matter, or a coated matter, which deteriorates the film hardness of the printed matter or the like.

[0003]

DISCLOSURE OF THE INVENTION The present invention provides a photoinitiator composition and a photocurable coating composition for the purpose of preventing the deterioration of the low odor property, the cured film hardness, and the curability of the printed matter and during printing. Is.

[0004]

The present invention relates to a photoinitiator composition having a molecular weight of 300 to 2,000, which is obtained by reacting an amine compound or amino compound having a hydroxyl group with dimethylaminobenzoic acid or benzoylbenzoic acid. A photoinitiator composition obtained by reacting dimethylaminobenzoic acid and benzoylbenzoic acid with an amine compound or an amino compound having a group,
Further, the present invention relates to a photocurable coating composition containing the above photoinitiator composition. Examples of the amine compound having a hydroxyl group of the present invention include ethanolamine and hydroxylpiperazine, and examples of the amino compound having a hydroxyl group include hydroxylmelamine and hydroxylisocyanurate.

Examples of ethanolamine include N, N-dimethylethanolamine, N, N-diethylethanolamine, N, N-dibutylethanolamine, N- (β-aminoethyl) ethanolamine, N-methylethanolamine, N- There are methyldiethanolamine and triethanolamine. N- as the hydroxyl piperazine
(2-hydroxyethyl) piperazine, N, N'-bis (2-hydroxyethyl) piperazine, N- (2-hydroxypropyl) piperazine, N, N'-bis (hydroxypropyl) piperazine, N- (2-hydroxy Ethyl) 2-methylpiperazine, N, N'-bis (2-hydroxyethyl) 2-methylpiperazine, N- (2-hydroxypropyl) 2-methylpiperazine, N, N'-
Examples include bis (2-hydroxypropyl) 2-methylpiperazine.

The hydroxyl melamine includes (hexa) methylol melamine and the like, and the hydroxy isocyanurate includes tris- (2-hydroxyethyl) isocyanurate and the like. Dimethylaminobenzoic acid is o
There are-, m-, p-dimethylaminobenzoic acid, but p-dimethylaminobenzoic acid is preferably used. Benzoylbenzoic acid includes o-, m-, p-benzoylbenzoic acid, and o-benzoylbenzoic acid is preferably used. In order to synthesize the photoinitiator composition of the present invention, first, an amine compound or amino compound having a hydroxyl group and dimethylaminobenzoic acid and / or benzoylbenzoic acid are charged into a reactor equipped with a stirrer, and it is necessary under a nitrogen stream. Accordingly, a reflux solvent such as toluene or xylene is added, and the temperature is gradually raised from 170 ° C. and the reaction is performed at 220 ° C. until the acid value becomes 10 or less. The reaction ratio between the amine compound or amino compound having a hydroxyl group and dimethylaminobenzoic acid and / or benzoylbenzoic acid is 0.1 to 0.1 or more of dimethylaminobenzoic acid and / or benzoylbenzoic acid per hydroxyl group. 1 mol, preferably 0.8
~ 1 mol.

The photoinitiator composition of the present invention has a molecular weight of 300.
˜2000, preferably 300˜1000. When the molecular weight is less than 300, it has a sublimation property and causes an odor. On the other hand, when the molecular weight is larger than the above value, the reaction initiation efficiency of the initiator is lowered and the curability of the curable coating composition is deteriorated by irradiation of ultraviolet rays. Generally, when a photoinitiator is used in the photocurable coating composition, an amine photoinitiator which is a hydrogen donor and a benzophenone system which is a hydrogen acceptor are used in combination. The photoinitiator composition of the present invention is a hydrogen donor, and a compound obtained by reacting an amine compound or an amino compound having a hydroxyl group with dimethylaminobenzoic acid has many groups having a hydrogen donating function in the molecule and is a hydrogen donor. Acts as. Therefore, the photoinitiator composition is used in combination with a hydrogen acceptor. Further, a reaction product containing an amine compound or amino compound having a hydroxyl group and benzoylbenzoic acid simultaneously has a hydrogen donor function and a hydrogen acceptor function in the molecule, and thus the reaction product can be used alone. Also, a conventionally known photoinitiator may be used in combination.

The photoinitiator composition of the present invention is used by being contained in the curable coating composition in an amount of 1 to 20% by weight. In the present invention, alkyd (meth) acrylate, polyester (meth) acrylate, epoxy (meth) acrylate, urethane (meth) acrylate and the like are used as the radically polymerizable resin of the curable coating composition. Further, resins having no radical-polymerizable property can also be used, and as these resins, there are resins having a softening point of 30 ° C. or higher, preferably resins having a softening point of 70 to 120 ° C., and more specifically, polyester and epoxy. Ester, urethane,
There is a diallyl phthalate resin.

Further, as the radically polymerizable monomer, (hydrogenated) bisphenol (A or F) alkylene oxide adduct di (meth) acrylate, neopentyl glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, glycerin is used. (Alkylene oxide) tri (meth) acrylate, tetramethylolmethane tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, (alkyl) phenol or polyhydric phenol alkylene oxide adduct (meth) acrylate, and other commercially available products. Any of the monomers can be used.

The composition ratio of the resin and the radical-polymerizable monomer is in the range of 0 to 60% by weight for the resin and 10 to 95% by weight for the radical-polymerizable monomer. When the curable coating composition is a printing ink, the incometer is used. The tack value is 5 to 1
5 poise / 25 ° C, 0.1-1 for overcoat varnish
It is appropriately blended so as to be 0 poise / 25 ° C. When using it as a printing ink, Benzi Yellow,
A pigment such as lake red, phthalocyanine blue or carbon black is used in an amount of 5 to 40% by weight. If necessary, additives such as anti-wear agents are used.

[0011]

EXAMPLES Examples will be shown below. In the examples, “part” means “part by weight” and “%” means “% by weight”. Example 1 [Synthesis example of photoinitiator composition] An amine compound or amino compound having a hydroxyl group, dimethylaminobenzoic acid and / or o-benzoylbenzoic acid, and xylene were charged into a four-necked flask equipped with a stirrer under a nitrogen stream. React at 170 ° C. Then, the temperature is gradually raised and the solvent is removed at 220 ° C. when the acid value becomes 10 or less. A photoinitiator composition was obtained in the same manner as in Example 1 with the formulations shown in Table 1.

[0012]

[Table 1]

Example 2 [Preparation of curable coating composition] Varnish: dipentaerythritol hexaacrylate 6
9.9% and hydroquinone 0.1% are charged and the temperature is raised to 100 ° C. Then, 30 parts of DT150 (Toyo Kasei Co., Ltd. diallyl phthalate resin) is gradually charged and melted out. The viscosity was 2100 poise (25 ° C). Printing ink is prepared by kneading each raw material. Since the overcoat varnish contains no pigment, it is produced by heating and melting at 50 to 100 ° C. Table 2 shows the ink formulations of Comparative Examples and Examples and the cured film performance thereof.

[0014]

[Table 2]

Yellow Pigment LIONOL YELLOW SGR-H Toyo Ink Mfg. Co., Ltd. Yellow Pigment Monomer 1 Dipentaerythritol Hexaacrylate Monomer 2 Pentaerythritol Tetraacrylate Kayakyua EPA Nippon Kayaku Co., Ltd. UV Initiator MOBB Methylorthobenzoylbenzoate Printing The ink performance was evaluated as follows. (1) Curability: In the case of printing ink in each curable coating, the ink (Comparative Example 1B, Examples 1B to 7B) was used with a RI tester 0.30 cc (a simple printing machine generally used in the printing ink industry. 0.15 cc on 20 cm x 25 cm paper
The ink is uniformly printed) and the overcoat varnish (Comparative Example 2B, Example 8B) is a bar coater # 3.
UV irradiation (high pressure mercury lamp 120W / cm3
(Light) After being evaluated by touch with a finger and dried and cured, the higher the conveyor speed (m / min) of the UV irradiation device, the better the curability. (2) Odor: Cured under the same conditions as curability. The printed matter was cut into small pieces, and the pieces were placed in a glass bottle and the odor was relatively judged by five panelists. (3) Pencil hardness: The pencil hardness of the printed matter cured under the same conditions as the curability.

[0016]

The photocurable coating composition of the present invention has an odor,
Good film hardness. It also has the advantage of a high curing speed.

Continuation of front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location G03F 7/028 // C08G 59/68 NLE 8416-4J

Claims (3)

[Claims] 1. A molecular weight of 300 to 2 obtained by reacting an amine compound or an amino compound having a hydroxyl group with dimethylaminobenzoic acid or benzoylbenzoic acid.
000 photoinitiator compositions. 2. A photoinitiator composition obtained by reacting an amine compound or an amino compound having a hydroxyl group with dimethylaminobenzoic acid and benzoylbenzoic acid. 3. A photocurable coating composition comprising the photoinitiator composition of claim 1 or 2.