Radiation-Curable Inkjet Ink for Stable Pigment Dispersion

The patent introduces a specific dispersing agent as an intermediary substance between the pigment and gelling agent. This dispersing agent has a specific molecular structure that preferentially binds to the pigment particles, creating a protective barrier that prevents the pigment from interacting with the gelling agent. The dispersing agent thus mediates the relationship between pigment and gelling agent, allowing the gelling agent to provide pinning properties while the dispersing agent maintains pigment dispersion stability.

The patent utilizes the phase transition property of the gelling agent, which transitions from a liquid state during ink ejection to a gel state after deposition on the substrate. This phase transition occurs rapidly after the ink droplet is ejected, causing the deposited ink to solidify and maintain its shape. This allows densely packed ink droplets to be ejected at high speed without coalescing, as each droplet rapidly gels upon contact with the substrate, preserving image quality while enabling high-speed recording.