KR100485996B1 - UV curable coating composition and optical recording medium using the same - Google Patents

Abstract

The present invention relates to an ultraviolet curable coating composition and an optical recording medium employing the same, and more particularly, to an ultraviolet curable coating composition for forming an ink receiving layer suitable for inkjet printing and an optical recording medium employing the same.

In this invention, the composition for ultraviolet curable coating containing a (meth) acrylate monomer, a (meth) acrylate oligomer, N-vinyl-2-pyrrolidone, an inorganic pigment, and an organic pigment is provided.

When the ink receiving layer is formed using the UV-curable coating composition of the present invention, not only the adhesion to the substrate is excellent, but also the water absorption, adsorption, dryness and water resistance with the aqueous ink used in the inkjet printing method are very excellent. A recording medium of excellent quality can be provided.

Description

UV curable coating composition and optical recording medium employing the same {UV curable coating composition and optical recording medium using the same}

The present invention relates to an ultraviolet curable coating composition and an optical recording medium employing the same, and more particularly, to an ultraviolet curable coating composition for forming an ink receiving layer suitable for inkjet printing and an optical recording medium employing the same.

In general, water-based ink used for inkjet printing is sprayed onto the recording medium through the nozzle of the printer head, absorbed, and fixed by natural drying, thereby outputting characters or images on the surface of the medium.

As such, the inkjet printing method for printing text and images on various recording media using water-based inks has the advantages of high economical efficiency, ease of coloration, high speed output, low noise, and the like. It is used. The inkjet printing method may be used for copy paper, which is generally used, but the image may be sufficiently absorbed with aqueous ink on the surface of a recording medium such as paper in order to improve the resolution of characters and images and to give better characteristics. Inkjet recording paper and the like, which are laminated with ink-receiving layers having enhanced characteristics of sharpening, are used.

However, recording media such as paper are made of absorbent surfaces, so that inkjet printing is easier and stacking of ink receiving layers for improving the output quality is easier. However, inkjet printing is applied to glass, steel plate and plastic surfaces having non-absorbing surfaces. Still difficult In order to enable inkjet printing on a recording medium having such a non-absorbing surface, many methods have been attempted to form an ink receiving layer on the surface of the medium. For example, Korean Patent Application Laid-Open No. 99-29618 provides a recording medium having an ink receiving layer containing a hydrophilic resin and a cationic compound. However, the technique has weak moisture resistance and stickiness on the surface, resulting in poor data storage. Is not preferred because it has problems. In addition, WO 99/16835 discloses an ink acceptor having a radiation curable compound containing a monofunctional (meth) acrylic monomer and a polyfunctional (meth) acrylic monomer and an absorbent inorganic or organic filler, but having a poor drying speed. It is not preferable because there is a problem of lowering the printing sharpness.

SUMMARY OF THE INVENTION The present invention has been made in an effort to provide an ultraviolet curable coating composition which is not only excellent in adhesion to a substrate but also enhanced in water absorption, adsorption, dryness, and water resistance with an aqueous ink used in an inkjet printing method.

Another object of the present invention is to provide an optical recording medium employing the composition.

In order to solve the above technical problem, in the present invention, an ultraviolet curable type including 100 parts by weight of (meth) acrylate monomer, 150 to 250 parts by weight of (meth) acrylate oligomer and 10 to 100 parts by weight of N-vinyl-2-pyrrolidone. It provides a coating composition.

The composition may further include 30 to 150 parts by weight of the inorganic pigment and 50 to 150 parts by weight of the organic pigment based on 100 parts by weight of the (meth) acrylate monomer.

As the (meth) acrylate monomer usable in the present invention, monofunctional or polyfunctional (meth) acrylate monomers can be used without particular limitation, and examples thereof include alkyl (meth) acrylate, (meth) acrylic acid, and (meth) acrylic. Nitrile, (meth) acrylamide, N-substituted (meth) acrylamide, N-methylol (meth) acrylamide, hydroxyethyl (meth) acrylate, carboxyethyl (meth) acrylate, (meth) acryloyl mol Porin, ethylene glycol mono (meth) acrylate, diethylene glycol mono (meth) acrylate, polyethylene glycol mono (meth) acrylate, dimethylaminopropyl (meth) acrylamide, tetrahydrofurfuryl (meth) acrylate, ethylene Glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, 1,6-hexane glycol di (meth) a Methacrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane di (meth) acrylate, and the like. It can also be used in combination of more than one type.

Examples of the alkyl (meth) acrylates include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate), t-butyl (meth) acrylate, and the like. Can be mentioned. Among these, monomers with high hydrophilicity having a hydroxyl group, a carboxyl group, an amino group, a morpholino group, a tetrahydrofurfuryl group, and the like are more preferable.

In the example of the said (meth) acrylate monomer, an alkyl (meth) acrylate, hydroxyethyl (meth) acrylate, carboxyethyl (meth) acrylate, diethylene glycol mono (meth) acrylate, ethylene glycol mono (meth) Even more preferable are acrylate, tetrahydrofurfuryl (meth) acrylate, polyethylene glycol di (meth) acrylate, and the like.

Such a (meth) acrylate monomer is used as a diluent for imparting workability.

As the (meth) acrylate oligomer usable in the present invention, monofunctional or polyfunctional (meth) acrylate oligomers can be used without particular limitation, and examples thereof include alkyl (meth) acrylate oligomers, (meth) acrylic acid oligomers, (meth) ) Acrylonitrile oligomer, (meth) acrylamide oligomer, N-substituted (meth) acrylamide oligomer, N-methylol (meth) acrylamide oligomer, hydroxyethyl (meth) acrylate oligomer, carboxyethyl (meth) acryl Elate oligomer, (meth) acryloylmorpholine oligomer, ethylene glycol mono (meth) acrylate oligomer, diethylene glycol mono (meth) acrylate oligomer, polyethylene glycol mono (meth) acrylate oligomer, dimethylaminopropyl (meth) acrylic Amide oligomer, tetrahydrofurfuryl (meth) acrylate oligomer , Ethylene glycol di (meth) acrylate oligomer, diethylene glycol di (meth) acrylate oligomer, polyethylene glycol di (meth) acrylate oligomer, 1,6-hexane glycol di (meth) acrylate oligomer, pentaerythritol Tetra (meth) acrylate oligomers, pentaerythritol (meth) acrylate oligomers, trimethylolpropane tri (meth) acrylate oligomers, trimethylolpropane di (meth) acrylate oligomers, and the like. It is also possible to use.

Examples of the alkyl (meth) acrylate oligomers include methyl (meth) acrylate oligomers, ethyl (meth) acrylate oligomers, propyl (meth) acrylate oligomers, n-butyl (meth) acrylate oligomers, t-butyl (meth) ) Acrylic oligomer etc. are mentioned. Among these, high hydrophilic oligomers having a hydroxyl group, a carboxyl group, an amino group, a morpholino group, a tetrahydrofurfuryl group, and the like are more preferable.

In the example of the said (meth) acrylate oligomer, alkyl (meth) acrylate, hydroxy (meth) acrylate, carboxyethyl (meth) acrylate, ethylene glycol mono (meth) acrylate, diethylene glycol mono (meth) Even more preferred are acrylate, polyethylene glycol mono (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, and the like.

The (meth) acrylate oligomer used in the present invention serves as a binder for fixing a material exhibiting a function to the subject, it is preferable to use 150 to 250 parts by weight based on 100 parts by weight of the (meth) acrylate monomer. If the amount is less than 150 parts by weight, the smearing phenomenon may occur, and if it exceeds 250 parts by weight, there is a problem that the drying becomes poor.

In addition, the average molecular weight of the (meth) acrylate oligomer may be in the range of 500 to 10,000, more preferably in the range of 700 to 5,000. The N-vinyl-2-pyrrolidone used in the present invention is a pigment and It is used to impart the compatibility of the oligomer and at the same time to increase the curing rate during UV curing, and to increase the fixing rate of the dye, the amount of which is preferably 10 to 100 parts by weight based on 100 parts by weight of (meth) acrylate. Do. If the amount of use exceeds 100 parts by weight, there is a problem that the viscosity is lowered, and if it is less than 10 parts by weight, there is a problem that the curing rate is lowered.

The inorganic pigments used in the present invention are not particularly limited, but may be alumina, silica gel, silica-alumina, talc, diatomaceous earth, calcium carbonate, calcium sulfate, zeolite, kaolin, talc, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, Zinc carbonate, satin white, aluminum silicate, calcium silicate, magnesium silicate, synthetic amorphous silica, colloidal silica, colloidal alumina, pseudo-boehmite, aluminum hydroxide, lithopone, magnesium carbonate, magnesium hydroxide, etc. Can be used, and these can also be used in combination of 2 or more types. The amount of the inorganic pigment is preferably 30 to 150 parts by weight based on 100 parts by weight of the (meth) acrylate, and when the amount is less than 30 parts by weight, there is a problem that the absorbency is lowered, and the amount of the inorganic pigment is 150 parts by weight. When the amount is exceeded, there is a problem that the viscosity is excessively increased. More preferred are mixtures of kaolin and calcium carbonate in the inorganic pigments.

Although it does not restrict | limit especially as an organic pigment which can be used by this invention, A styrenic plastic pigment, an acrylic plastic pigment, polyethylene, a microcapsule, urea resin, a melamine resin, etc. are mentioned, It can also be used in combination of 2 or more types. Do. It is preferable to use 50-150 weight part of these usage-amounts with respect to 100 weight part of (meth) acrylate monomers, and when the usage-amount is less than 50 weight part, there exists a problem that a water absorption falls, and the usage-amount exceeds 150 weight part It is not preferable because there is a problem that the viscosity increases. Among the organic pigments, polymethylene urea is more preferable.

Since the coating composition of this invention superposes | polymerizes by the method of irradiating an ultraviolet-ray, it is preferable that a photoinitiator is contained. As a photoinitiator which can be used for this invention, if it is normally used as photoinitiators, such as (alpha)-hydroxy ketone, acetophenone type, benzoin type, a benzophenone type, a thioxanthone type, it can be used without a restriction | limiting in particular, You may use together 2 or more types of compounds. It is preferable to use 5-30 weight part with respect to 100 weight part of (meth) acrylates, and when the usage-amount of such a photoinitiator is used, there exists a problem that a hardening rate will fall, and when it exceeds 30 weight part There is a problem that excessive curing occurs. Preferred photopolymerization initiators are α-hydroxy ketones.

When preparing the coating composition of the present invention, it is preferable to use a surfactant or a dispersant to reduce the mutual attraction between the compounds to smoothly disperse the pigment and increase the stability of the coating, for example modified polyacrylate Acidic polyester polyamides, unsaturated polyamides, carboxylates, hydroxy functional unsaturated modified carboxylic acids, and the like. It is preferable to use 5-50 weight part with respect to 100 weight part of rates. If the amount is less than 5 parts by weight, there is a problem that the dispersibility is poor, and if it exceeds 50 parts by weight, there is a problem that the functionality of the ink is lowered.

In the present invention, a crosslinking agent may be further included to further enhance the hydrophilicity of the UV-curable coating composition of the present invention. Examples of such additional crosslinking agents include methylol melamine, methylol urea, methylol hydroxypropylene urea, and isocyanate. Etc. can be mentioned.

The UV curable coating composition of the present invention may be used in addition to the above components as other additives for enhancing physical properties, such as light resistance enhancers, dye / pigment stabilizers, thickeners, fluidity improvers, antifoaming agents, foam inhibitors, mold release agents, foaming agents, penetrants, coloring dyes, Fluorescent whitening agents, preservatives, water-resistant agents, film-forming agents and the like can be mixed and used appropriately.

In order to polymerize and cure the ultraviolet curable coating composition of the present invention, ultraviolet rays are irradiated. In addition to ultraviolet rays, an electron beam may also be used. As for the intensity | strength of the ultraviolet-ray irradiated to a coating film, about 100-500w / inch is preferable, and the wavelength has preferable 250-400 nm. In addition, a conventional method such as a mercury lamp can be used as the ultraviolet light source, and each of the compounds undergoes a process of radical polymerization and curing by ultraviolet irradiation.

By applying the UV-curable coating composition of the present invention to the surface of the substrate, and irradiated with ultraviolet rays, it is possible to form a preferable ink receiving layer which can easily output characters or images by an inkjet printing method.

Usually, as a base material to which the composition for UV cure coating of this invention is apply | coated, all the normal recording media, for example, paper, vinyl, glass, a plastics, etc., can be used, and especially it is especially suitable for the optical recording medium etc. whose usage is increasing recently. Can be used. Such an optical recording medium is generally composed of a substrate, a recording layer, a reflective layer, and a protective film, and the protective film is composed of a hydrophobic component such as polyester resin, polycarbonate resin, acrylic resin, and the like, and is generally used for inkjet printing. When water-based ink is applied on the protective film, a proper output cannot be obtained. However, if the ink-receiving layer is formed as an intermediate layer by applying the ultraviolet-curable coating composition of the present invention to the protective film and irradiating with ultraviolet rays, the aqueous ink used for inkjet printing can be easily output to the recording medium.

Such an ink receiving layer is required to have excellent adhesion to a hydrophobic substrate, water resistance under high temperature and high humidity, ink absorption, stability of printing, and long-term storage. When the ink receiving layer is formed using the ultraviolet curable coating composition of the present invention, it becomes possible to form an excellent ink receiving layer that can satisfy all of the above properties.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

Example 1

Each component of the ultraviolet curable coating composition which has the following composition was mixed for 1 hour in the mixer, and the coating liquid was prepared.

100 parts by weight of ethylene glycol monoacrylate

200 parts by weight of ethylene glycol monoacrylate oligomer

50 parts by weight of N-vinyl-2-pyrrolidone

10 parts by weight of α-hydroxy ketone

Calcium Carbonate 35 parts by weight

Kaolin 35 parts by weight

Polymethyl Urea 70 parts by weight

20 parts by weight of modified polyacrylate

The coating liquid obtained by mixing the composition having the composition as described above is coated on the protective film of the disc (SKC Gold / Blue CD-R), which is a commercially available recordable CD-R, as a optical recording medium on which a protective film is formed. Formed. The coating film was irradiated with ultraviolet rays using a mercury lamp (UC LIGHT 36/150) to give a lamp intensity of 2.5KW on the irradiated surface, and the coating film was cured to produce an optical recording medium having an ink receiving layer of about 15 탆.

Example 2

Each component of the ultraviolet curable coating composition having the following composition was mixed in a mixer for 1 hour to prepare a coating liquid.

100 parts by weight of acrylamide

200 parts by weight of acrylamide oligomer

70 parts by weight of N-vinyl-2-pyrrolidone

10 parts by weight of α-hydroxy ketone

Calcium Carbonate 35 parts by weight

Kaolin 35 parts by weight

Polymethyl Urea 70 parts by weight

20 parts by weight of modified polyacrylate

The composition having the composition described above was applied and polymerized in the same manner as in Example 1 to obtain an optical recording medium.

Example 3

Each component of the ultraviolet curable coating composition which has the following composition was mixed for 1 hour in the mixer, and the coating liquid was prepared.

100 parts by weight of carboxyethyl methacrylate

200 parts by weight of carboxyethyl methacrylate oligomer

80 parts by weight of N-vinyl-2-pyrrolidone

10 parts by weight of α-hydroxy ketone

Calcium Carbonate 35 parts by weight

Kaolin 35 parts by weight

Polymethyl Urea 70 parts by weight

20 parts by weight of modified polyacrylate

The composition having the composition described above was applied and polymerized in the same manner as in Example 1 to obtain an optical recording medium.

Comparative Example 1

Each component of the ultraviolet curable coating composition which has the following composition was mixed for 1 hour in the mixer, and the coating liquid was prepared.

100 parts by weight of carboxyethyl methacrylate

20 parts by weight of α-hydroxy ketone 50 parts by weight of calcium carbonate

50 parts by weight of kaolin

30 parts by weight of polymethyl urea

10 parts by weight of modified polyacrylate

The composition having the composition described above was applied and polymerized in the same manner as in Example 1 to obtain an optical recording medium.

Comparative Example 2

Each component of the ultraviolet curable coating composition which has the following composition was mixed for 1 hour in the mixer, and the coating liquid was prepared.

100 parts by weight of carboxyethyl methacrylate

100 parts by weight of carboxyethyl methacrylate oligomer

20 parts by weight of α-hydroxy ketone 50 parts by weight of calcium carbonate

50 parts by weight of kaolin

Polymethyl Urea 70 parts by weight

20 parts by weight of modified polyacrylate

The composition having the composition described above was applied and polymerized in the same manner as in Example 1 to obtain an optical recording medium.

Experimental Example 1 Surface Property Measurement

By using a color printer (product name: Signature II, manufactured by Parco Co.) on the surface of the optical recording medium obtained in Examples 1 to 3 and Comparative Examples 1 to 2 on which the ink receiving layer was formed, the text and images were printed by hand. Rubbing directly to measure the surface properties and the results are shown in Table 1 below.

◎: fairly smooth and not sticky at all

O: smooth and not sticky

△: smooth but sticky

X: rough and sticky

Experimental Example 2: Measurement of Ink Absorption

Characters and images were output using a color printer (product name: Signature II, manufactured by Parco Co.) on the surface of the optical recording medium obtained in Examples 1 to 3 and Comparative Examples 1 and 2 on which an ink receiving layer was formed to use a microscope. The printed portion was observed and the results are shown in Table 1 below.

◎: No spread

O: There is bleeding below 0.4 mm

△: bleeding from 0.4 to 0.8 mm

X: There is bleeding more than 0.8 mm

Experimental Example 3: Measurement of Drying Rate

Printing surface after outputting characters and images on the surface of the optical recording medium obtained in Examples 1 to 3 and Comparative Examples 1 to 2 using a color printer (product name: Signature II, manufactured by Parco). Was measured by touching the ink by hand, and the results are shown in Table 1 below.

◎: within 30 seconds

O: 30 seconds to 2 minutes

△: 2 to 10 minutes

X: 10 minutes or more

Experimental Example 4: Measurement of Water Resistance

Printed surface after outputting characters and images on the surface of the optical recording medium obtained in Examples 1 to 3 and Comparative Examples 1 to 2 using a color printer (product name: Signature II, manufactured by Parco). After standing for 1 minute in running water to observe the character or image visually, the change in concentration was measured and the results are shown in Table 1 below.

◎: no change

△: somewhat changed

X: much changed

Experimental Example 5: Print Quality Measurement

After printing stripes on each color using a color printer (product name: Signature II, manufactured by Parco) on the surface of the optical recording medium obtained in Examples 1 to 3 and Comparative Examples 1 to 2, the naked eye After observing the printed surface, the results are shown in Table 1 below.

◎: Uniform color

△: somewhat non-uniform

X: much non-uniform

Experimental Example 6: Measurement of Preservation

30 ° C. after printing characters and images on the surface of the optical recording medium obtained in Examples 1 to 3 and Comparative Examples 1 to 2 using a color printer (product name: Signature II, manufactured by Parco). After standing for 20 days under the condition of / 80% RH, the state of the printed surface before and after storage was observed and the results are shown in Table 1 below.

◎: No change in printing state

△: printing state slightly changed

X: Print status changes a lot

Experimental Example 7: Measurement of Adhesion with Substrate

After measuring adhesion to the surface of the optical recording medium on which the ink receiving layer is formed, which is obtained in Examples 1 to 3 and Comparative Examples 1 to 2, that is, surface peeling, the results are shown in Table 1 below.

◎: no surface peeling

△: surface peeling occurs somewhat

X: A lot of surface peeling occurs

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Surface properties ◎ ◎ ◎ △ X Ink absorbency ◎ ◎ ◎ △ ◎ Drying rate ◎ O O O O Water resistance ◎ ◎ ◎ X O Print quality ◎ ◎ ◎ O O Preservation ◎ △ ◎ X X Adhesiveness to the base material ◎ ◎ ◎ ◎ ◎

As can be seen from the results in Table 2, when the ink receiving layer is formed using the UV-curable coating composition of the present invention, not only the adhesion to the substrate is excellent, but also the water absorption of the water-based ink used in the inkjet printing method Since the adsorption property, drying property, and water resistance are very excellent, a recording medium of excellent quality can be provided.

Claims (18)

100 parts by weight of (meth) acrylate monomer, 150 to 250 parts by weight of (meth) acrylate oligomer and 10 to 100 parts by weight of N-vinyl-2-pyrrolidone, The said (meth) acrylate monomer is alkyl (meth) acrylate, (meth) acrylic acid, (meth) acrylonitrile, (meth) acrylamide, N-substituted (meth) acrylamide, N-methylol (meth) acryl Amide, hydroxyethyl (meth) acrylate, carboxyethyl (meth) acrylate, (meth) acryloyl morpholine, ethylene glycol mono (meth) acrylate, diethylene glycol mono (meth) acrylate, polyethylene glycol mono ( Meth) acrylate, dimethylaminopropyl (meth) acrylamide, tetrahydrofurfuryl (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylic Rate, 1,6-hexane glycol di (meth) acrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol (meth) acrylate, trimethylolpropane tri (meth ) Acrylate and trimethylolpropane di (meth) at least one member selected from the group consisting of acrylate, The (meth) acrylate oligomer is alkyl (meth) acrylate oligomer, (meth) acrylic acid oligomer, (meth) acrylonitrile oligomer, (meth) acrylamide oligomer, N-substituted (meth) acrylamide oligomer, N-methyl Roll (meth) acrylamide oligomer, hydroxyethyl (meth) acrylate oligomer, carboxyethyl (meth) acrylate oligomer, (meth) acryloyl morpholine oligomer, ethylene glycol mono (meth) acrylate oligomer, diethylene glycol mono (Meth) acrylate oligomer, polyethylene glycol mono (meth) acrylate oligomer, dimethylaminopropyl (meth) acrylamide oligomer, tetrahydrofurfuryl (meth) acrylate oligomer, ethylene glycol di (meth) acrylate oligomer, diethylene Glycol di (meth) acrylate oligomer, polyethylene glycol di (meth) arc Relate oligomer, 1,6-hexane glycol di (meth) acrylate oligomer, pentaerythritol tetra (meth) acrylate oligomer, pentaerythritol (meth) acrylate oligomer, trimethylolpropane tri (meth) acrylate UV-curable coating composition, characterized in that at least one member selected from the group consisting of oligomers and trimethylolpropane di (meth) acrylate oligomer. delete The method of claim 1, wherein the (meth) acrylate monomer is alkyl (meth) acrylate, hydroxyethyl (meth) acrylate, carboxyethyl (meth) acrylate, diethylene glycol mono (meth) acrylate, ethylene glycol It is at least 1 type selected from the group which consists of a mono (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, and polyethyleneglycol di (meth) acrylate. delete The method of claim 1, wherein the (meth) acrylate oligomer is alkyl (meth) acrylate, hydroxy (meth) acrylate, carboxyethyl (meth) acrylate, ethylene glycol mono (meth) acrylate, diethylene glycol A composition comprising at least one member selected from the group consisting of mono (meth) acrylate, polyethylene glycol mono (meth) acrylate, and tetrahydrofurfuryl (meth) acrylate. The composition according to claim 1, further comprising 30 to 150 parts by weight of the inorganic pigment with respect to 100 parts by weight of the (meth) acrylate monomer. The inorganic pigment of claim 6, wherein the inorganic pigment is alumina, silica gel, silica-alumina, talc, diatomaceous earth, calcium carbonate, calcium sulfate, zeolite, kaolin, talc, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, satin. Composition comprising at least one member selected from the group consisting of white, aluminum silicate, calcium silicate, magnesium silicate, synthetic amorphous silica, colloidal silica, colloidal alumina, pseudoboehmite, aluminum hydroxide, lithopone, magnesium carbonate and magnesium hydroxide . 8. The composition of claim 7, wherein the inorganic pigment is calcium carbonate, kaolin or a mixture thereof. The composition according to claim 1, further comprising 50 to 150 parts by weight of an organic pigment based on 100 parts by weight of the (meth) acrylate monomer. The composition of claim 9, wherein the organic pigment is at least one selected from the group consisting of styrenic plastic pigments, acrylic plastic pigments, polyethylene, microcapsules, urea resins and melamine resins. The composition of claim 10, wherein the organic pigment is a urea resin. The composition according to claim 11, wherein the organic pigment is polymethylene urea. The composition according to claim 1, further comprising 30 to 150 parts by weight of an inorganic pigment and 50 to 150 parts by weight of an organic pigment, based on 100 parts by weight of the (meth) acrylate monomer. The method of claim 13, wherein the inorganic pigment is alumina, silica gel, silica-alumina, talc, diatomaceous earth, calcium carbonate, calcium sulfate, zeolite, kaolin, talc, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, satin At least one selected from the group consisting of white, aluminum silicate, calcium silicate, magnesium silicate, synthetic amorphous silica, colloidal silica, colloidal alumina, pseudoboehmite, aluminum hydroxide, lithopone, magnesium carbonate and magnesium hydroxide, and the organic pigment The composition is characterized in that it is at least one member selected from the group consisting of styrenic plastic pigments, acrylic plastic pigments, polyethylene, microcapsules, urea resins and melamine resins. The composition according to claim 14, wherein the inorganic pigment is calcium carbonate, kaolin or a mixture thereof, and the organic pigment is a urea resin. The composition according to claim 1, further comprising 5 to 50 parts by weight of the surfactant or dispersant based on 100 parts by weight of the (meth) acrylate. A recording medium having an ink receiving layer formed on at least one surface of a hydrophobic substrate by polymerizing and curing the ultraviolet curable coating composition according to any one of claims 1, 3, and 5 to 16. 18. An ink receiving layer formed by polymerizing and curing the UV-curable coating composition according to any one of claims 1, 3, and 5 to 16 on an opposite surface of an optical recording medium for performing optical read / write. One optical recording medium.