JP2015193675A - Active energy ray-curable ink and printed matter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an active energy ray-curable ink composition that is excellent in transfer property and adhesiveness to an olefin-based resin film having low polarity such as polyethylene and polypropylene, and is excellent in scratch resistance and blocking resistance, and a printed matter using the ink composition.SOLUTION: An active energy ray-curable ink is provided, which comprises a photopolymerizable acrylate monomer, a binder resin, a photopolymerization initiator, and organopolysiloxane, and in which the organopolysiloxane has a number average molecular weight of 100,000 or more and less than 500,000. A printed matter is obtained by printing with the above active energy ray-curable ink.

Description

The present invention relates to an active energy ray-curable ink and a printed matter obtained by printing the active energy ray-curable ink. More specifically, the present invention relates to an active energy ray-curable ink excellent in transferability and adhesion to an olefin resin film such as polyethylene or polypropylene, and excellent in scratch resistance and blocking resistance, and a printed matter thereof.

Conventionally, printed materials for forms, printed materials for various books, printed materials for packaging such as carton paper, various printed materials for plastics, seals, printed materials for labels, printed materials for arts, printed materials for arts (printed products for art, printed beverages, canned foods, etc.) In order to obtain various printed materials, various printing methods such as lithographic (ordinary lithographic using fountain solution and waterless lithographic plate not using fountain solution), letterpress, intaglio, and stencil printing are adopted. Ink is suitable for each printing method. An active energy ray curable ink is known as one of such inks (Non-patent Documents 1 and 2).

Conventional active energy ray-curable inks have a feature of instantaneous curing by photopolymerization, but it is difficult to achieve both the instantaneous curing and the adhesion to a substrate to be coated and printed. That is, as the instantaneous curability is pursued, volume shrinkage occurs in the cured film of the ink, and the flexibility of the film is impaired, so that the adhesion to the substrate is significantly reduced.

On the other hand, high-quality printed materials are required for printing, and accordingly, the types of target substrates are diverse. For example, a highly transparent polyolefin material from the standpoint of cosmetics, a synthetic paper having a PET (polyethylene terephthalate) film base from the standpoint of water resistance, or a PET film that has excellent abrasion resistance and scratch resistance with the spread of prepaid cards The use of a chemically synthesized material as a base material to give physical properties that could not be realized with conventional paper, such as printing on itself, is rapidly spreading.

In general, active energy ray-curable inks often adhere to highly polar polyester resins, polyvinyl chloride resins, polycarbonate resins, ABS resins, etc., but low polarity olefin resin films such as polyethylene and polypropylene are As a characteristic of the material itself, since the polarity is very low, the acceptability of the ink is poor, and it is difficult to ensure sufficient adhesion and inking of the ink.

In Patent Document 1, as a method for developing adhesion to an olefin resin film, an active energy ray-curing property having adhesion comprising a rosin epoxy acrylate, a polyurethane resin having a carbon-carbon unsaturated group, and an acrylic monomer. A resin composition is provided.

Further, Patent Document 2 provides an active energy ray-curable ink composition having adhesiveness containing a C5 to C7 petroleum resin as a method of developing adhesiveness and transferability to an olefinic resin film. .

As described above, as a method of expressing the adhesion and transferability to the olefin resin film, there has been devised to contain a material having a high affinity with the base material, but in order for any method to express the adhesion Since it is essential to suppress volume shrinkage (curing shrinkage) associated with the photopolymerization reaction, the resulting ink film has a low degree of polymerization, and printing troubles such as blocking and scratching often occur at present.
Therefore, there is a need for an active energy ray-curable ink that has adhesion and transferability to an olefin-based resin film and is less likely to cause printing troubles such as scratches and blocking.

JP-A-8-143635 JP 2010-189537 A

An object of the present invention is to provide an active energy ray-curable ink and a printed matter obtained by printing the active energy ray-curable ink. More specifically, an active energy ray curable ink excellent in transferability and adhesion to an olefin resin film such as polyethylene or polypropylene, and excellent in scratch resistance and blocking resistance, and the active energy ray curable ink are printed. Is to provide a printed matter.

  As a result of sincere research to solve the above problems, active energy ray curable ink containing a specific organopolysiloxane in an active energy ray curable ink containing a photopolymerizable acrylate monomer, a binder resin and a photopolymerization initiator. It was found that the mold ink was excellent in transferability and adhesion to an olefin resin film such as polyethylene or polypropylene, and excellent in scratch resistance and blocking resistance, and the present invention was completed.

  That is, the present invention includes an active energy comprising a photopolymerizable acrylate monomer, a binder resin, a photopolymerization initiator, and an organopolysiloxane having a number average molecular weight of 70,000 to 600,000. The present invention relates to a linear curable ink.

  Furthermore, the present invention relates to the above active energy ray-curable ink, wherein the organopolysiloxane is dimethylpolysiloxane.

  Furthermore, the present invention relates to the active energy ray-curable ink, wherein the organopolysiloxane is contained in an amount of 0.1 to 10 parts by weight in 100 parts by weight of the active energy ray-curable ink.

Furthermore, the present invention relates to the above active energy ray curable ink, wherein the active energy ray curable ink further contains a powder wax, and the particle diameter of the powder wax is 2 μm or more and less than 10 μm.

  Furthermore, this invention relates to the printed matter formed by printing the said active energy ray curable ink on a base material.

According to the present invention, an active energy ray-curable ink excellent in adhesion and transferability to a low-polarity olefin resin film such as polyethylene or polypropylene, and excellent in scratch resistance and blocking resistance, and printed using the same. It became possible to provide the printed matter.

The active energy rays used in the present invention are ultraviolet rays and electron beams, but are not necessarily limited thereto.

Examples of the organopolysiloxane used in the present invention include dimethylpolysiloxane, methylphenylpolysiloxane, and dimethylpolysiloxane modified with carboxylic acid, hydroxyl group and amino group, dimethylpolysiloxane, and methylphenylpolysiloxane. Dimethylpolysiloxane.

The number average molecular weight of the organopolysiloxane used in the present invention is 70,000 to 600,000. A number average molecular weight in the range of 70,000 to 600,000 is preferable in terms of scratch resistance, blocking resistance, adhesion, and transferability. On the other hand, if it is less than 70,000, adhesion and transferability deteriorate, and the effect of scratch resistance is not exhibited. If it exceeds 600,000, compatibility with other components in the ink composition becomes poor, and component separation occurs. And uneven transfer.

The number average molecular weight in the present invention is measured using GPC (gel permeation chromatography) “HLC-8220” manufactured by Tosoh Corporation. A calibration curve was prepared by standard polystyrene conversion. A sample was dissolved in tetrahydrofuran, and measurement was performed under the conditions of a flow rate of 0.6 ml / min and a column temperature of 40 ° C. using tetrahydrofuran as a developing solvent.

The addition amount of the organopolysiloxane used in the present invention is preferably 0.1 to 10 parts by weight in 100 parts by weight of the active energy ray-curable ink. If it is this range, it is easy to solve various physical properties which are the subject of this invention. In addition, it is more preferable that it is 0.2-5 weight part.

Examples of the powder wax used in the present invention include hard fine particles such as polyethylene (PE), polypropylene (PP), polystyrene, polystyrene rubber, and polytetrafluoroethylene (PTFE). The average particle diameter is 2 μm to 10 μm. preferable.

The average particle diameter of the powder wax used in the present invention is preferably 2 μm to 10 μm in terms of blocking resistance.

The average particle size in the present invention is a particle having a cumulative particle size of 50 in a volume particle size distribution measured using a laser diffraction scattering type particle size distribution measuring device “LA-920 (using dry measurement unit LY-208)” manufactured by Horiba, Ltd. The diameter (D50) was defined and described as the average particle diameter.

In the present invention, the binder resin used as appropriate is a thermosetting or thermoplastic resin, such as polyester, polyvinyl chloride, poly (meth) acrylic ester, epoxy resin, polyurethane resin, petroleum resin, cellulose derivative. (For example, ethyl cellulose, cellulose acetate, nitrocellulose), vinyl chloride vinyl acetate copolymer, polyamide resin, polyvinyl acetal resin, diallyl phthalate resin, synthetic rubber such as butadiene-acrylonitrile copolymer, and the like. These resins can be used alone or in combination of two or more thereof. In either case, a resin that is soluble in the photopolymerizable acrylate monomer is used. In the present invention, the binder resin is preferably used in the range of 5 to 30% by weight in order to obtain a viscosity suitable for offset printing as an ink composition.

  In the present invention, the photopolymerizable acrylate monomer refers to monofunctional or polyfunctional (meth) acrylates, and is used in the range of 30 to 70% by weight in order to obtain a viscosity suitable for offset printing as an ink composition.

Monofunctional monomers include alkyl (having 2 to 18 carbon atoms) (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, dodecyl (meth) acrylate, stearyl ( Examples thereof include benzyl (meth) acrylate, isobornyl (meth) acrylate, cyclohexyl (meth) acrylate, and tricyclodecane monomethylol (meth) acrylate.

Polyfunctional (meth) acrylates include ethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate , Polypropylene glycol di (meth) acrylate, butylene glycol di (meth) acrylate, pentyl glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, hydroxypivalyl hydroxypivalate di (meth) acrylate (commonly called manda), Hydroxypivalyl hydroxypivalate dicaprolactonate di (meth) acrylate, 1,6 hexanediol di (meth) acrylate, 1,8-octanedio Rudi (meth) acrylate, 1,9-nonanediol di (meth) acrylate, 1,2-hexadecanediol di (meth) acrylate, 2-methyl-2,4-pentanediol di (meth) acrylate, bisphenol A tetraethylene Oxide adduct di (meth) acrylate, bisphenol F tetraethylene oxide adduct di (meth) acrylate, water-added bisphenol A tetraethylene oxide adduct di (meth) acrylate, water-added bisphenol F tetraethylene oxide adduct di (meth) Acrylate, water-added bisphenol A di (meth) acrylate, water-added bisphenol F di (meth) acrylate, glycerin tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylol group Lopantricaprolactonate tri (meth) acrylate, trimethylolethane tri (meth) acrylate, trimethylolhexane tri (meth) acrylate, trimethyloloctanetri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra ( (Meth) acrylate, diglycerin tetra (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, ditrimethylolpropane tetracaprolactonate, tetra (meth) acrylate, ditrimethylolethanetetra (meth) acrylate, ditrimethylolbutanetetra ( (Meth) acrylate, ditrimethylolhexanetetra (meth) acrylate, ditrimethyloloctanetetra (meth) acrylate, di Pentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, can be used tripentaerythritol hexa (meth) acrylate, tripentaerythritol hepta (meth) acrylate, a tripentaerythritol octa (meth) acrylate.

Furthermore, there is an alkylene oxide adduct (meth) acrylate of an aliphatic alcohol compound as the acrylic monomer of the present invention. Examples of the alkylene oxide adduct (meth) acrylate monomer of an aliphatic alcohol compound include mono- or poly (1-20) alkylene (C2 to C20) oxide adducts (alkylene oxide) of an aliphatic alcohol compound. 2-20 alkylene oxide adduct (meth) acrylate, for example methanol mono- or poly (1-20) alkylene (C2-C20) oxide adduct (as alkylene oxide, for example, ethylene oxide, propylene oxide, butylene oxide) (meth) acrylate And ethanol mono- or poly (1-20) alkylene (C2-C20) oxide adducts, etc. Further, ethylene glycol mono- or poly (1-20) al can be used as a bifunctional monomer. Examples of the adduct of lene (C2 to C20) oxide (alkylene oxide such as ethylene oxide, propylene oxide, butylene oxide) di (meth) acrylate, diethylene glycol mono or poly (2 to 20) alkylene (C2 to C20) oxide adduct, etc. Furthermore, glycerin poly (2-20) alkylene (C2-C20) oxide adducts (eg, alkylene oxide such as ethylene oxide, propylene oxide, butylene oxide) tri (meth) acrylate, trimethylolpropane poly (2 -20) Alkylene (C2-C20) oxide adducts and the like are exemplified, but not limited thereto.

The poly (2-20) used in the present invention has a polymerization degree of an alkylene (C2-C20) oxide adduct.

  As the photopolymerization initiator used in the present invention, as a hydrogen abstraction type, benzophenone, p-methylbenzophenone, p-chlorobenzophenone, tetrachlorobenzophenone, methyl benzoylbenzoate, 4-phenylbenzophenone, hydroxybenzophenone, 4-benzoyl- 4'-methyl-diphenyl sulfide, 2-isopropylthiocisanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, acetophenone / aryl ketone initiator, 4,4'-bis (Diethylanino) benzophenone, 4,4′-bis (dimethylamino) benzophenone, isoamyl p-dimethylaminobenzoate, p-dimethylaminoacetophenone / dialkylaminoaryl ketone initiator Thioxanthone, and the like xanthone Part halogen-substituted and multi-ring carbonyl-based initiators.

  Further, as a cleavage type photopolymerization initiator, benzoin, benzoin methyl ether, benzoin isopropyl ether, α-acrylbenzoyl benzoin system, benzyl, 2-methyl-2-morpholino (4-thiomethylphenyl) propan-1-one, 2- Benzyl-2-dimethylamino-1- (4-morpholinophenyl) -1-butanone, benzylmethyl ketal, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- (4- Isopropylphenyl-2-hydroxy-2-methylpropan-1-one, 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone, 4- (2-acryloyloxyethoxy) phenyl-2-hydroxy-2- Propylke Emissions, and the like diethoxyacetophenone.

  Examples of photopolymerization initiation assistants include triethanolamine, methyldiethanolamine, triisopropanolamine / aliphatic amine, 4,4′-diethylaminobenzophenone, ethyl 2-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, 4 -Isoamyl dimethylaminobenzoate, dibutylethanolamine are mentioned.

The photopolymerization initiator is used in the range of 3 to 15% by weight during the composition with respect to 100% by weight of the composition in order to cure the ink composition under the UV lamp irradiation environment for offset printing.

  On the other hand, various additives for the purpose of anti-friction, anti-blocking, slip, anti-scratch, and dark reaction can be used as additives in the composition. Leveling agents and antistatic agents can be used as necessary. An agent, surfactant, antifoaming agent, polymerization inhibitor and the like may be added.

  As the coloring material of the present invention, a pigment is mainly used. As the pigment, white pigment such as titanium oxide, mineral furnace yellow, navel yellow, naphthol yellow S, hansa yellow G, quinoline yellow lake, permanent yellow NCG, Yellow pigments such as Tartrazine Lake, Indanthrene Brilliant Orange RK, Pirazone Orange, Vulcan Orange, Benzidine Orange G, Indanthren Brilliant Orange GK and other orange pigments, Permanent Red 4R, Lionol Red, Pyrarozone Red, Watching Lettuce Calcium Red pigments such as salt, lake red D, brilliant carmine 6B, eosin lake, rhodamine lake B, alizarin lake, brilliant carmine 3B, first violet B, methyl Purple pigments such as iolet lake, bitumen, cobalt blue, alkali blue lake, Victoria blue lake, phthalocyanine blue, metal-free phthalocyanine blue, phthalocyanine blue partially chlorinated, blue pigments such as first sky blue and indanthrene blue BC, pigment green Examples thereof include green pigments such as B, malachide green lake, and fine series green G, black pigments such as carbon black, acetylene black, run black, and aniline black, and extender pigments such as barite powder, barium carbonate, and benton.

The pigment according to the present invention is used in the range of 0 to 55% by weight with respect to 100% by weight of the composition. In the case of 0% by weight, it is sometimes called OP varnish instead of ink.

  In the present invention, as the substrate, paper or film used for lithographic printing can be used without any particular limitation. Specifically, as the paper, coated paper such as art paper, coated paper, cast paper, high quality paper, medium quality paper, non-coated paper such as newspaper paper, and synthetic paper such as YUPO are selected. Moreover, a polyethylene film, a polyester film, a polypropylene film etc. are mentioned as a film.

EXAMPLES Next, although an Example is given and this invention is demonstrated further more concretely, this invention is not limited by these Examples. In the present invention, “part” represents part by weight, and “%” represents% by weight.

An active energy ray-curable ink composition was prepared according to the following formulation.

(Create ink varnish)
A polyester resin was used as the binder resin, and a 1-3 functional acrylate monomer was used as the photopolymerizable monomer. A polyester resin and a 1-3 functional acrylate monomer were heated and mixed by heating, and the resin ratio was dissolved at a ratio of 30 to 50% by weight to prepare a varnish.

(Creation of ink composition)
The varnish, photopolymerizable acrylate monomer, color pigment, photopolymerization initiator, polyorganosiloxane, powder wax, and other additives were mixed at the blending ratio shown in Table 1 using a butterfly mixer, and three rolls Each ink composition was prepared by dispersing it so that the maximum particle size was 7.5 μm or less and adjusting the viscosity to a constant viscosity with a spread meter.

(Measurement of print samples for comparative evaluation)
A 160 W / cm metal halide lamp is applied to a PP film (polypropylene film “Idemitsu Super Array SG140” and below) with a predetermined amount of each ink composition prepared and printed using an RI tester (simple print transfer device). The ink composition was cured by irradiation at a predetermined irradiation amount to prepare a comparative evaluation print sample.

<Evaluation of adhesion>
A PP film is coated with a predetermined amount of each ink composition prepared using an RI tester (simple print transfer device), and irradiated with a 160 W / cm metal halide lamp at a predetermined irradiation amount. The composition was cured to produce a comparative evaluation print sample. The adhesion with the PP film was evaluated by the following criteria using a cellophane tape peeling test.
(Evaluation criteria)
○… not peeled at all ○ △… partly peeled △… about half peeled △ ×… partly peeled off ×… all peeled off

<Evaluation of metastasis>
A print sample for comparative evaluation was prepared in the same manner as in the adhesion evaluation, and the ink deposition property of the solid part was evaluated five times.
(Evaluation criteria)
○… The ink is uniformly transferred over the entire surface ○ △… Partially transferred unevenness Δ… Many transferred unevenness Δ ×… Only partially transferred ×… Not transferred at all

<Evaluation of scratch resistance (scratch resistance)>
A comparative evaluation print sample was prepared by the same method as the adhesion evaluation, and evaluated by rubbing with a nail.
(Evaluation criteria)
○… No rubbing ○ △… Surface layer rubbing Δ… Intermediate layer rubbing Δ ×… Bottom rubbing ×… No coating

<Evaluation of blocking resistance>
A printed sample for comparative evaluation was prepared in the same manner as the adhesion evaluation, a PP film was overlaid on the printed sample, and a load of 500 g / cm ² was applied in an oven at 40 ° C. for 24 hours. The film was peeled off, and the adhesion (backing) of the ink to the PP film side was evaluated.
○… No ink adherence ○ △ Partial adherence △… Many adherence △ ×… Mostly adherence ×… Whole adherence

The formulation design of Examples and Comparative Examples is as follows.
(1) Table 1 (Examples 1-14)
1) Use an organopolysiloxane having a number average molecular weight of 100,000 or more and less than 500,000 2) Use a powder wax having an average particle size of 2.0 μm or more and less than 10.0 μm (2) Table 1 (Examples 15 to 17)
1) Use an organopolysiloxane having a number average molecular weight of 100,000 or more and less than 500,000 2) Use a powder wax having an average particle diameter of less than 2.0 μm (3) Table 1 (Examples 18 to 20)
1) Use an organopolysiloxane having a number average molecular weight of 100,000 or more and less than 500,000 2) No powder wax (4) Table 2 (Comparative Example 1)
1) No organopolysiloxane used 2) No powder wax used (5) Table 2 (Comparative Examples 2 to 4)
1) Use an organopolysiloxane having a number average molecular weight of less than 100,000 2) No powder wax (6) Table 2 (Comparative Examples 5 to 7)
1) No use of organopolysiloxane 2) Use of powder wax (7) Table 2 (Comparative Examples 8 to 16)
1) Use an organopolysiloxane with a number average molecular weight of less than 100,000 2) Use powder wax

From the results of Tables 1 and 2, according to the examples of the present invention, active energy ray curing with excellent adhesion and transferability to low-polarity olefin resin films such as polyethylene or polypropylene, and excellent scratch resistance and blocking resistance. It was found that a mold ink could be obtained.

Claims (5)

  An active energy ray-curable ink comprising a photopolymerizable acrylate monomer, a binder resin, a photopolymerization initiator, and an organopolysiloxane having a number average molecular weight of 70,000 to 600,000. 2. The active energy ray-curable ink according to claim 1, wherein the organopolysiloxane is dimethylpolysiloxane.   The active energy ray-curable ink according to claim 1 or 2, wherein the organopolysiloxane is contained in an amount of 0.1 to 10 parts by weight in 100 parts by weight of the active energy ray-curable ink. The active energy ray-curable ink according to any one of claims 1 to 3, wherein the active energy ray-curable ink further contains a powder wax, and the particle diameter of the powder wax is 2 µm or more and less than 10 µm. .   A printed matter obtained by printing the active energy ray-curable ink according to claim 1 on a substrate.