Ink jet recording method, ultraviolet-ray curable ink, and ink jet recording apparatus

1. An ink jet recording method comprising:

ejecting an ultraviolet-ray curable ink of which a viscosity at 28° C. is 8 mPa·s or more from a head to a recording medium; and

curing the ultraviolet-ray curable ink attached to the recording medium, wherein the ultraviolet-ray curable ink is heated such that a temperature of the ejected ultraviolet-ray curable ink is in a range of 28° C. to 39° C., and a viscosity of the ultraviolet-ray curable ink at the heated temperature of the ejected ultraviolet-ray curable ink is in a range of 15 mPa·s or less,

wherein a light source used for the curing of the ultraviolet-ray curable ink is a light emitting diode, and

wherein the light emitting diode applies ultraviolet rays which have a peak intensity of 800 mW/cm 2 or more.

2. The ink jet recording method according to claim 1 , wherein recording is performed using a line type ink jet recording apparatus which includes a line head with a length equal to or more than a length corresponding to a width of a recording medium as the head.

3. The ink jet recording method according to claim 1 , wherein recording is performed using an ink jet recording apparatus in which at least a part of an ink path for supplying the ultraviolet-ray curable ink from an ink container to the head is an ink circulation path for circulating the ultraviolet-ray curable ink.

4. The ink jet recording method according to claim 3 , wherein an ink inflow amount of the ultraviolet-ray curable ink which is supplied from the ink circulation path to the head is twice or more the maximum ink ejection amount in which the ultraviolet-ray curable ink is ejected from the head.

5. The ink jet recording method according to claim 3 , wherein a heating mechanism which heats the ultraviolet-ray curable ink is provided at a position other than a position which is connected to at least the head in the ink circulation path.

6. The ink jet recording method according to claim 3 , wherein there are a plurality of heads to which the ultraviolet-ray curable ink is supplied from the ink circulation path, and the ultraviolet-ray curable ink is ejected from the plurality of heads.

7. The ink jet recording method according to claim 1 , wherein the ultraviolet-ray curable ink includes (meth)acrylic acid esters containing a vinyl ether group expressed in the following Formula (I):

CH 2 ═CR 1 —COOR 2 —O—CH═CH—R 3   (I)

wherein R 1 indicates a hydrogen atom or a methyl group, R 2 indicates a divalent organic residue having 2 to 20 carbon atoms, and R 3 indicates a hydrogen atom or a monovalent organic residue having 1 to 11 carbon atoms.

8. The ink jet recording method according to claim 7 , wherein the ultraviolet-ray curable ink further includes a monofunctional (meth)acrylate (here, excluding (meth)acrylic acid esters containing a vinyl ether group expressed in Formula (I)).

9. The ink jet recording method according to claim 1 , wherein the light emitting diode applies ultraviolet rays which have a peak intensity of 1000 mW/cm 2 or more.

10. The ink jet recording method according to claim 1 , wherein an epoxy resin is used for the head.

11. The ink jet recording method according to claim 1 , wherein the light emitting diode applies ultraviolet rays which have a peak intensity of 800 to 3000 mW/cm 2 .

12. The ink jet recording method according to claim 1 , wherein the light emitting diode applies ultraviolet rays which have an irradiation energy of 200 mJ/cm 2 or more.

13. The ink jet recording method according to claim 1 , wherein the temperature of the ejecting ink is in a range of 34° C. to 39° C.

14. The ink jet recording method according to claim 1 , wherein the ultraviolet-ray curable ink includes an acylphosphine oxide compound as a photopolymerization initiator.

15. The ink jet recording method according to claim 14 , wherein a content of the acylphosphine oxide compound is 5 to 15 mass % with respect to a total mass of the ultraviolet-ray curable ink.

16. The ink jet recording method according to claim 1 , wherein the ultraviolet-ray curable ink includes a monofunctional (meth) acrylate and a bifunctional or higher (meth) acrylate.

17. An ink jet recording method comprising:

ejecting an ultraviolet-ray curable ink of which a viscosity at 28° C. is 8 mPa·s or more from a head to a recording medium; and

curing the ultraviolet-ray curable ink attached to the recording medium, wherein the ultraviolet-ray curable ink is heated such that a temperature of the ejected ultraviolet-ray curable ink is in a range of 28° C. to 39° C., and a viscosity of the ultraviolet-ray curable ink at the heated temperature of the ejected ultraviolet-ray curable ink is in a range of 15 mPa·s or less,

wherein the ultraviolet-ray curable ink includes (meth)acrylic acid esters containing a vinyl ether group expressed in a following Formula (I):

CH 2 ═CR 1 —COOR 2 —O—CH═CH—R 3   (I)

wherein R 1 indicates a hydrogen atom or a methyl group, R 2 indicates a divalent organic residue having 2 to 20 carbon atoms, and R 3 indicates a hydrogen atom or a monovalent organic residue having 1 to 11 carbon atoms.

18. The ink jet recording method according to claim 17 , wherein a content of the (meth)acrylate acid esters containing a vinyl ether group expressed in the Formula (I) is 10 to 70 mass % with respect to the total mass of the ultraviolet-ray curable ink.

19. The ink jet recording method according to claim 17 , wherein the ultraviolet-ray curable ink includes monofunctional (meth)acrylate other than the (meth)acrylate acid esters containing a vinyl ether group expressed in the Formula (I).

20. The ink jet recording method according to claim 17 , wherein the ultraviolet-ray curable ink includes bifunctional (meth)acrylate, or trifunctional or higher (meth)acrylate.