As image recording methods for forming an image on a recording medium such as paper based on an image data signal, there are an electrophotographic method, sublimation type and melt type thermal transfer methods, an inkjet method, etc. Among them, since the inkjet method can be carried out by inexpensive equipment and carries out image formation directly on a recording medium by discharging an ink only in a required image area, use of the ink is efficient and the running cost is low.
As an ink composition used in such a recording method, for example, ink compositions described in Patent Documents 1 to 4 have been proposed.