Ultraviolet-curable ink jet ink composition
Provided is an ultraviolet-curable ink jet ink composition with excellent curability and storage stability, the composition containing a monomer A represented by Formula (I): CH 2 ═CR 1 —COOR 2 —O—CH═CH—R 3 (wherein R 1 represents a hydrogen atom or a methyl group, R 2 represents a C 2 -C 20 divalent organic residue, and R 3 represents a hydrogen atom or a C 1 -C 11 monovalent organic residue); a (meth)acrylated amine compound; a hindered amine compound other than the (meth)acrylated amine compound; and a photopolymerization initiator.
1. An ultraviolet-curable ink jet ink composition comprising:
a monomer A represented by Formula (I):
CH 2 ═CR 1 —COOR 2 —O—CH═CH—R 3 (I)
(wherein R 1 represents a hydrogen atom or a methyl group, R 2 represents a C 2 -C 20 divalent organic residue, and R 3 represents a hydrogen atom or a C 1 -C 11 monovalent organic residue);
a hindered amine compound, the hindered amine compound being either 2,2,6,6-tetramethyl-4-hydroxypiperidine-1-oxyl or 4,4′-[1,10-dioxo-1,10-decanediyl)bis(oxy)]bis[2,2,6,6-tetramethyl]-1-piperidinyloxy; and
a photopolymerization initiator
wherein the photopolymerization initiator includes an acylphosphine oxide compound.
2. The ultraviolet-curable ink jet ink composition according to claim 1 , wherein the monomer A is 2-(vinyloxyethoxy)ethyl (meth)acrylate.
3. The ultraviolet-curable ink jet ink composition according to claim 1 , wherein the content of the monomer A is in the range of 10 to 80% by mass, based on the total mass of the ink composition.
4. The ultraviolet-curable ink jet ink composition according to claim 1 , wherein the content of the compound having a 2,2,6,6-tetramethylpiperidinyl-N-oxyl radical is in the range of 0.05 to 3% by mass, based on the total mass of the ink composition.
5. The ultraviolet-curable ink jet ink composition according to claim 1 , further comprising 5 to 40% by mass of phenoxyethyl (meth)acrylate, based on the total mass of the ink composition.
6. The ultraviolet-curable ink jet ink composition according to claim 1 , wherein the ultraviolet-curable ink jet ink composition is curable by irradiating ultraviolet radiation with an emission peak wavelength ranging from 350 to 420 nm, at an irradiation energy of 300 mJ/cm 2 or less.
7. The ultraviolet-curable ink jet ink composition according to claim 1 , wherein the ultraviolet-curable ink jet ink composition is curable to a thin film having a thickness of 0.5 to 3 μm.
8. The ultraviolet-curable ink jet ink composition according to claim 1 , wherein the hindered amine includes 2,2,6,6-tetramethyl-4-hydroxypiperidine-1-oxyl.
9. The ultraviolet-curable ink jet ink composition according to claim 1 , wherein the photopolymerization initiator includes 7% by mass or more and 15% by mass or less of an acylphosphine oxide compound based on the total mass of the ink jet composition.
10. The ultraviolet-curable ink jet ink composition according to claim 1 , wherein the photopolymerization initiator includes 0.5% by mass or more and 5% by mass or less of a thioxanthone compound, based on the total mass of the ink jet composition.
11. The ultraviolet-curable ink jet ink composition according to claim 1 , wherein the photopolymerization initiator includes 7% by mass or more of an acylphosphine oxide compound and 0.5% by mass or more of a thioxanthone compound, based on the total mass of the ink jet composition.