JP2001311022A - Active energy ray curing ink and optical recording medium using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain both an active energy ray curing ink capable of forming an ink receiving layer excellent in brightness, water resistance and adhesion of an image to a substrate and an optical recording medium having the ink receiving layer formed from the ink. SOLUTION: This active energy ray curing ink is characterized as comprising (A) an ammonium salt represented by a specific general formula, (B) an active energy ray curing monomer capable of dissolving the ammonium salt (A) and (C) a filler. The optical recording medium has the ink receiving layer formed from the ink.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an active energy ray-curable ink capable of forming an ink receiving layer capable of printing image information and character information on one surface of an optical recording medium, and an active energy ray-curable ink. The present invention relates to an optical recording medium having an ink receiving layer.

[0002]

2. Description of the Related Art In recent years, there has been an increasing demand for providing an ink receiving layer on the back surface of a surface on which laser light is incident on an optical recording medium, and printing and organizing patterns and characters representing the recorded contents of the medium. In particular, there is a need for an optical recording medium that can be printed by an inkjet method.

[0003] As such an optical recording medium capable of ink jet recording, JP-A-6-60432 and JP-A-8-102090 disclose an ink containing a hydrophilic resin and a solvent, which is dried to form an ink receiving layer. An optical recording medium applied to the surface is described. However, these methods have a drawback that they require a long drying time for coating.

Therefore, various types of optical recording media have been proposed in which the drying time is reduced by utilizing active energy rays such as ultraviolet rays and electron beams for drying the ink. JP-A-7-16910
Japanese Patent Application Laid-Open No. 0-96409 discloses an optical recording medium coated with an ultraviolet-curable ink containing a filler and a hydrophilic polymer. Kaihei 10-2593
No. 40 proposes an optical recording medium in which a radiation-curable ink containing a hydrophobic polymer and a natural fiber powder is applied and dried.

Further, in Japanese Patent Application Laid-Open No. 11-16210, an optical recording medium coated with an ultraviolet-curable ink containing a polyvinyl butyral resin, a hydrophilic monomer and silicon dioxide is dried, and in Japanese Patent Application Laid-Open No. 11-116875, a water-soluble monomer is used. An optical recording medium has been proposed in which a radiation-curable ink containing a water-absorbing polymer powder is applied and dried. In these optical recording media, characters and designs can be written using water-based ink or oil-based ink. However, in printing using an ink-jet printer, there is a high demand for print quality, and the ink must not be blurred and the image must be printed clearly. However, there is a problem that the bleeding is still insufficient in the optical recording medium as described above, and furthermore, when water adheres to the surface, the ink is eluted, and the printed characters and designs become indistinguishable. .

[0006] In many cases, dyes having an anion such as sulfonic acid are used as dyes for ink-jet inks. In order to improve water resistance, cationic dyes are fixed in the ink-receiving layer of ink-jet paper and OHP films. There has been proposed a method of incorporating an agent or the like (Japanese Patent Application Laid-Open No. 61-26089). Japanese Patent Application Laid-Open No. 8-318673 also proposes an optical recording medium obtained by curing an ink containing a compound having a quaternary ammonium base and a compound having a carboxylic acid group. However, in order to maintain compatibility with other components in the ink, the total carbon number of the alkyl group attached to the quaternary nitrogen is 4
As described above, the number is preferably 5 or more, and good ink receptivity based on the affinity with the ink of the compound having the alkyl group having 3 or less carbon atoms cannot be exhibited.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide excellent image clarity, water resistance and substrate resistance, such as no decrease in print density and no peeling of the entire layer even when wiped off after moisture has adhered. It is an object of the present invention to provide an active energy ray-curable ink capable of forming an ink receiving layer having excellent adhesion, and to provide an optical recording medium having an ink receiving layer formed from the ink.

[0008]

That is, the present invention provides an ammonium salt (A) represented by the following general formula (1) and an active energy ray-curable monomer (B) capable of dissolving (A). The object has been achieved by providing an active energy ray-curable ink containing a filler (C) and an optical recording medium having an ink receiving layer formed from the ink.

Embedded image (In the formula 1, R 1 represents hydrogen or a methyl group.
2 represents an oxygen or imino group. R3 has 1 to 8 carbon atoms
And an oxy group and a carbonyl group may be interposed. R3 may have a hydroxyl group as a substituent. R
4 represents hydrogen or a methyl group. X- represents an anion. )

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific examples of the ammonium salt (A) used in the present invention include N, N-dimethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylate, N, N N-dimethylamino-2-hydroxypropyl (meth) acrylate, N,
N-dimethylaminoethyl (meth) acrylamide,
Hydrochlorides such as N, N-dimethylaminopropyl (meth) acrylamide, sulfates, nitrates, formates, alkyl sulfates, alkyl carboxylate salts, and salts quaternized with methyl chloride or methyl bromide. Examples include, but are not limited to:

[0010] Of these, particularly preferred compounds include
Trimethyl-2- (methacryloyloxy) ethylammonium chloride, trimethyl-2- (methacryloyloxy) ethylammonium bromide, trimethyl-2- (acryloyloxy) ethylammonium chloride, trimethyl-2- (acryloyloxy) ethylammonium bromide, trimethyl- 3- (methacryloyloxy) propyl ammonium chloride, trimethyl-3- (methacryloyloxy) propyl ammonium bromide, trimethyl-3- (acryloyloxy) propyl ammonium chloride, trimethyl-3- (acryloyloxy) propyl ammonium bromide, trimethyl-2- Hydroxy-3- (methacryloyloxy) propylammonium chloride, trimethyl-2-h Proxy-3- (methacryloyloxy) propyl ammonium bromide, trimethyl-2
-Hydroxy-3- (acryloyloxy) propylammonium chloride, trimethyl-2-hydroxy-
3- (acryloyloxy) propylammonium bromide, trimethyl-2- (methacryloylamino) ethylammonium chloride, trimethyl-2- (methacryloylamino) ethylammonium bromide, trimethyl-2- (acryloylamino) ethylammonium chloride, trimethyl-2- (Acryloylamino) ethylammonium bromide, trimethyl-2-
(Methacryloylamino) propyl ammonium chloride, trimethyl-2- (methacryloylamino) propyl ammonium bromide, trimethyl-2- (acryloylamino) propyl ammonium chloride, and trimethyl-2- (acryloylamino) propyl ammonium bromide.

These ammonium salts (A) may be used alone or in combination of two or more. The content of these compounds in the ink is preferably 1 to 50% by weight, more preferably 5 to 30% by weight. If the content of these compounds is too low, the image will bleed and the water resistance will be poor. On the other hand, if the content is too large, the compatibility with other ink components deteriorates, and there is a problem in use such as an increase in the viscosity of the ink.

Specific examples of the active energy ray-curable monomer (B) having an ethylenically unsaturated group and capable of dissolving the ammonium salt (A) of the general formula (1) include N-
Acryloylmorpholine, N-vinylformamide, 2
-Hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono Examples thereof include (meth) acrylate and N-vinylpyrrolidone, but are not limited thereto. Among these, N-vinylformamide is particularly preferable in consideration of drying properties and bleeding after printing with an inkjet printer.

These compounds (B) may be used alone or in combination of two or more. The content of these compounds in the ink is not particularly limited as long as the ammonium salt (A) of the general formula (1) is dissolved in the ink, but is usually 15 to 50% by weight.

As the filler (C) used in the present invention, a water-absorbing / oil-absorbing organic or inorganic filler is used. Specifically, silica as the inorganic filler,
Talc, kaolin, calcium carbonate, magnesium carbonate, barium sulfate, aluminum hydroxide and the like, as organic fillers such as lignin, protein, cellulose and other powders, polyethylene, silicone resin, acrylic resin,
Polyacrylate, polymethacrylate,
Examples include, but are not limited to, fine particles of styrene resin, polyester, polycarbonate, modified melamine resin, polyvinyl alcohol, polyamide, polyacrylamide, polyvinyl pyrrolidone, and the like, and crosslinked fine particles thereof. Of these, silica or polyamide fine particles are preferred. Furthermore, the average particle size is 0.001.
Silica with a size of from 10 μm to 10 μm is particularly preferred.

These fillers (C) may be used alone or in combination of two or more. The content of these fillers in the ink is 5 to 60% by weight, more preferably 1 to 60% by weight.
It is preferably from 0 to 50% by weight. If the content of these fillers is too low, the penetration of the solvent will be slow, and drying during printing with an inkjet printer will be poor. If the content is too large, the film becomes brittle.

In the present invention, a polyfunctional monomer or oligomer may be added as a crosslinking agent for increasing the hardness of the film. Specific examples of the polyfunctional monomer include neopentyl glycol di (meth) acrylate, 1,6 hexanediol di (meth) acrylate, bisphenol A di (meth) acrylate, bisphenol F di (meth) acrylate, and trihydroxyethyl isocyanurate. Di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, trihydroxyethyl isocyanurate tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate , Dipentaerythritol penta (meth) acrylate, ethylene oxide-modified or propylene oxide-modified products of these compounds, and (poly) ethylene glycol Distearate (meth) acrylate, (poly) propylene, glycol di (meth) acrylate and the like but is not limited thereto. Examples of the polyfunctional oligomer include urethane acrylate, epoxy acrylate, and polyester acrylate, but are not limited thereto.

Ultraviolet rays, electron beams and the like are used as active energy rays for curing the ink of the present invention. When ultraviolet rays are used, it is necessary to contain a photopolymerization initiator. A sensitizer may be added as needed. Specific examples of the photopolymerization initiator and the sensitizer include 2,2-dimethoxy-1,2-diphenylethan-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone, and 2-hydroxy-2-methyl-1- Phenyl-propane-1-
On, benzophenone, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-
Propan-1-one, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl)- Butanone-1, bis (2,6-
Dimethoxybenzoyl) -2,4,4-trimethyl-pentylphosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, benzyldimethylketal , 2,
4,6-trimethylbenzophenone, oligo [2-hydroxy-2-methyl-1- (4- (1-methylvinyl)
Phenyl) propanone], 2-isopropylthioxanthone, 2,4-diethylthioxanthone, [4- (methylphenylthio) phenyl] phenylmethanone, ethylanthraquinone, isoamyl p-dimethylaminobenzoate, ethyl p-dimethylaminobenzoate Examples thereof include esters, but are not limited to these.

The active energy ray-curable ink of the present invention may contain a non-reactive compound, an antifoaming agent, a leveling agent, a lubricant, a plasticizer, an antioxidant, a polymerization inhibitor, an ultraviolet absorber, Combustion agents, pigments, dyes, rheology modifiers and the like can also be used as appropriate.

The components used in the active energy ray-curable ink of the present invention are preferably selected in consideration of safety.

As a method for applying the active energy ray-curable ink of the present invention to an optical recording medium, a bar coating method, a blade coating method, an air knife coating method, a roll coating method, a screen printing method, and the like can be used.

[0021]

EXAMPLES Each compound was blended at the weight ratio shown in Table 1 and stirred with a stirrer to obtain Examples 1-4 and Comparative Examples 1-4.
Ink 4 was obtained. The inks of Examples 1 to 4 and Comparative Examples 1 and 2 were applied on the protective film of the compact disc by 30
Screen printing was performed using a 0 mesh screen.
Immediately thereafter, it is irradiated with ultraviolet rays, cured, and has a thickness of 20 μm.
Was formed. On top of these ink receiving layers is an inkjet printer Signature III
(PRIMERA), and the ink drying property, water resistance, and print quality were evaluated according to the following evaluation methods. Table 1 shows the results. In Comparative Examples 3 and 4, the ammonium salt did not dissolve in the ink.

(1) Ink Drying Property The printing surface of the ink jet printer was touched with a finger, and the drying time until the ink did not adhere to the finger was measured, and judged according to the following criteria. A: Drying time is within 30 seconds. ：: Drying time is 30 seconds to 2 minutes. Δ: Drying time was 2 to 5 minutes. X: Drying time is 5 minutes or more.

(2) Water resistance The printed surface is exposed to running water for 1 minute, and the change in the image is observed.
It was determined according to the following criteria. ：: Little change before and after exposure to running water. Δ: Density reduction and bleeding are observed in the printed image. ×: The printed image disappeared and reading was impossible. Or the film peels.

(3) Print Quality The printed surface was visually observed or observed using a loupe, and judged according to the following criteria. ：: The image is clear without bleeding. Δ: Slight bleeding was observed in the image. X: The image is severely blurred.

[0025]

[Table 1]

* 1 to 5 in the table indicate the following. * 1: Made by Crossfield * 2: Made by Toray * 3: Aronix M5600 manufactured by Toagosei Co., Ltd. * 4: Aronix M245 manufactured by Toagosei Co., Ltd. * 5: Darocure 1 manufactured by Ciba Specialty Chemicals
173 / Lucillin TPO manufactured by BSF, mixed at a weight ratio of 8: 2.

As is clear from the results shown in Table 1, the inks of Examples 1 to 4 can form an ink receiving layer having excellent drying properties, water resistance and printing quality.

[0028]

According to the present invention, it is possible to form an ink receiving layer having excellent image clarity when printed on the surface with an ink jet printer using an aqueous ink, and having excellent water resistance and adhesion to a substrate. . Further, since active energy rays are used as a method for drying the ink, the drying time is extremely short as compared with the method of evaporating the solvent. In addition, there is an advantage that the load on the environment is small because almost no volatile solvent is generated.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C056 EA13 FC01 2H086 BA01 BA15 BA31 BA33 BA34 BA37 4J039 AD10 AD12 AF02 AF07 BA16 BA18 BA21 BA23 BA30 BA32 BC18 EA06 EA08 EA46 GA24

Claims (4)

[Claims] 1. An ammonium salt (A) represented by the following general formula (1), an active energy ray-curable monomer (B) capable of dissolving (A), and a filler (C). Active energy ray curable ink. Embedded image (In the general formula (1), R 1 represents hydrogen or a methyl group; R 2 represents oxygen or an imino group; R 3 is an alkylene group having 1 to 8 carbon atoms which may be interposed with an oxy group and a carbonyl group. (It may have a hydroxyl group as a substituent, R4 represents hydrogen or a methyl group, and X- represents an anion.) 2. The active energy ray-curable ink according to claim 1, wherein the active energy ray-curable monomer (B) is N-vinylformamide. 3. An optical recording medium having an ink receiving layer formed from an active energy ray-curable ink, wherein the ink comprises an ammonium salt (A) or (A) represented by the following general formula (1). An optical recording medium comprising an active energy ray-curable ink containing a dissolvable active energy ray-curable monomer (B) and a filler (C). Embedded image (In the general formula (1), R 1 represents hydrogen or a methyl group; R 2 represents oxygen or an imino group; R 3 is an alkylene group having 1 to 8 carbon atoms which may be interposed with an oxy group and a carbonyl group. (It may have a hydroxyl group as a substituent, R4 represents hydrogen or a methyl group, and X- represents an anion.) 4. The optical recording medium according to claim 3, wherein said ink receiving layer is an ink jet ink receiving layer.