Ink jet recording method

An ink jet recording method using an ink jet recording apparatus including a plurality of heads including first and second heads that respectively eject droplets of first and second radiation-curable ink compositions that are different from each other onto a recording medium, a plurality of first light sources that respectively emit an active radiation to irradiate the droplets on the recording medium, the second head being located next to the first head in a first direction, and the first and second heads being located in a carriage, the method comprising:

• transporting the recording medium in a second direction perpendicular to the first direction;
• ejecting the droplets of the first and second radiation-curable ink compositions from the first and second heads onto the recording medium while the first and second heads are scanning in the first direction;
• performing an irradiation by irradiating the droplets of the first and second radiation-curable ink compositions with the active radiation from the plurality of first light sources at a first irradiation energy, one of the plurality of first light sources being located next to the first head in the first direction, another of the plurality of first light sources being located next to the second head in the first direction;
• and
• performing a further irradiation by irradiating the droplets of the first and second radiation-curable ink compositions irradiated by the plurality of first light sources, the further irradiation being conducted by a second light source at a second irradiation energy, the second light source being located further on a downstream side of the second direction than the plurality of heads and the plurality of first light sources, wherein
• each of the plurality of first light sources includes an LED,
• the each of the first and second radiation-curable ink compositions contains a photopolymerization initiator of 5% to 15% by mass,
• the photopolymerization initiator contains an acylphosphine oxide-based photopolymerization initiator, and
• energy, which is required for curing 90% of the first and second radiation-curable ink compositions, is in a range of 120 to 300 mJ/cm2.

An ink jet recording method using an ink jet recording apparatus including a plurality of heads including first and second heads that respectively eject droplets of first and second radiation-curable ink compositions that are different from each other onto a recording medium, a plurality of first light sources that respectively emit an active radiation to irradiate the droplets on the recording medium, the second head being located next to the first head in a first direction, and the first and second heads being located in a carriage, the method comprising:

• transporting the recording medium in a second direction perpendicular to the first direction;
• ejecting the droplets of the first and second radiation-curable ink compositions from the first and second heads onto the recording medium while the first and second heads are scanning in the first direction;
• performing an irradiation by irradiating the droplets of the first and second radiation-curable ink compositions with the active radiation from the plurality of first light sources at a first irradiation energy, one of the plurality of first light sources being located next to the first head in the first direction, another of the plurality of first light sources being located next to the second head in the first direction;
• and
• performing a further irradiation by irradiating the droplets of the first and second radiation-curable ink compositions irradiated by the plurality of first light sources, the further irradiation being conducted by a second light source at a second irradiation energy, the second light source being located further on a downstream side of the second direction than the plurality of heads and the plurality of first light sources, wherein
• each of the plurality of first light sources includes an LED,
• the each of the first and second radiation-curable ink compositions contains a photopolymerization initiator of 5% to 15% by mass,
• the photopolymerization initiator contains an acylphosphine oxide-based the photopolymerization initiator, and
• a total irradiation energy of the first and second irradiation energies is greater than or equal to E90(mJ/cm2) at which the first and second radiation-curable ink compositions are 90% cured.

An ink jet recording method using an ink jet recording apparatus including a plurality of heads including first and second heads that respectively elect droplets of first and second radiation-curable ink compositions that are different from each other onto a recording medium, a plurality of first light sources that respectively emit an active radiation to irradiate the droplets on the recording medium, the second head being located next to the first head in a first direction, and the first and second heads being located in a carriage, the method comprising:

• transporting the recording medium in a second direction perpendicular to the first direction;
• ejecting the droplets of the first and second radiation-curable ink compositions from the first and second heads onto the recording medium while the first and second heads are scanning in the first direction;
• performing an irradiation by irradiating the droplets of the first and second radiation-curable ink compositions with the active radiation from the plurality of first light sources at a first irradiation energy, one of the plurality of first light sources being located next to the first head in the first direction, another of the plurality of first light sources being located next to the second head in the first direction;
• and
• performing a further irradiation by irradiating the droplets of the first and second radiation-curable ink compositions irradiated by the plurality of first light sources, the further irradiation being conducted by a second light source at a second irradiation energy, the second light source being located further on a downstream side of the second direction than the plurality of heads and the plurality of first light sources, wherein
• each of the plurality of first light sources includes an LED,
• the each of the first and second radiation-curable ink compositions contains a photopolymerization initiator of 5% to 15% by mass,
• the photopolymerization initiator contains an acylphosphine oxide-based photopolymerization initiator, and
• the further irradiation is performed after 500 ms has elapsed from the landing of the droplets of first and second radiation-curable ink compositions to the recording medium.