Photocurable ink composition and inkjet recording method

1. A photocurable ink composition comprising:

at least one compound that is selected from a group consisting of N-vinylformamide, a urethane oligomer, ethylene glycol monoallyl ether, diethylene glycol monoallyl ether, trimethylolpropane diallyl ether, trimethylolpropane monoallyl ether, glycerol monoallyl ether, allyl glycidyl ether, pentaerythritol triallyl ether, hydroxybutyl vinyl ether, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate and 4-hydroxybutyl acrylate;

a radical photopolymerization initiator;

a hindered amine compound; and

a metallic pigment,

the metallic pigment being aluminum or an aluminum alloy;

the metallic pigment being plate-like particles wherein metallic pigment has a light transmittance at 395 nm in the thickest direction of 0.8% or more.

2. A photocurable ink composition comprising:

a polymerizable compound;

a radical photopolymerization initiator;

at least one compound that is selected from a group consisting of alkanethiol, alkylenedithiol, and polyvalent thiol;

a hindered amine compound; and

a metallic pigment,

the metallic pigment being aluminum or an aluminum alloy;

the metallic pigment being plate-like particles; and

the metallic pigment being plate-like particles wherein metallic pigment has a light transmittance at 395 nm in the thickest direction of 0.8% or more.

3. The photocurable ink composition as defined in claim 2 , comprising:

at least one compound that is selected from a group consisting of N-vinylformamide, a urethane oligomer, ethylene glycol monoallyl ether, diethylene glycol monoallyl ether, trimethylolpropane diallyl ether, trimethylolpropane monoallyl ether, glycerol monoallyl ether, allyl glycidyl ether, pentaerythritol triallyl ether, hydroxybutyl vinyl ether, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate and 4-hydroxybutyl acrylate as the polymerizable compound.

4. The photocurable ink composition as defined in claim 2 , comprising:

a compound including an acrylic group or a methacrylic group as the polymerizable compound.

5. The photocurable ink composition as defined in claim 1 , the hindered amine compound having a 2,2,6,6-tetramethylpiperidine structure.

6. The photocurable ink composition as defined in claim 2 , the hindered amine compound having a 2,2,6,6-tetramethylpiperidine structure.

7. The photocurable ink composition as defined in claim 1 , the metallic pigment being prepared by pulverizing a metal deposited film.

8. The photocurable ink composition as defined in claim 2 , the metallic pigment being prepared by pulverizing a metal deposited film.

9. The photocurable ink composition as defined in claim 1 ,

when a major axis, a minor axis, and a thickness of each of the plate-like particles in a plane are respectively referred to as X, Y, and Z, a circle-equivalent 50% average particle diameter of each of the plate-like particles being determined based on the X-Y plane area and in a range from 0.5 to 3 micrometers.

10. The photocurable ink composition as defined in claim 2 ,

when a major axis, a minor axis, and a thickness of each of the plate-like particles in a plane are respectively referred to as X, Y, and Z, a circle-equivalent 50% average particle diameter of each of the plate-like particles being determined based on the X-Y plane area and in a range from 0.5 to 3 micrometers.

11. An inkjet recording method of discharging droplets of an ink composition to a recording medium so that the droplets adhere to the recording medium, the method comprising:

generating an image having metallic gloss by using the photocurable ink composition as defined in claim 1 .

12. An inkjet recording method of discharging droplets of an ink composition to a recording medium so that the droplets adhere to the recording medium, the method comprising:

generating an image having metallic gloss by using the photocurable ink composition as defined in claim 2 .