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 becomes 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 a monofunctional (meth) acrylate and a bifunctional or higher (meth) acrylate, a content of the monofunctional (meth) acrylate being from 35 mass % to 90 mass % of the ink.

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

10. The ink jet recording method according to claim 9 , wherein the light emitting diode applies ultraviolet rays which have a peak intensity of 800 mW/cm 2 or more.

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

12. The ink jet recording method according to claim 1 ,

wherein a content of the bifunctional (meth)acrylate is from 5 mass % to 50 mass % of the ink, and

wherein the monofunctional (meth)acrylate includes a monofunctional (meth)acrylate having an aromatic ring skeleton in a molecule, the temperature of the ejected ink being in a range of 33° C. to 39° C.