Inkjet ink and inkjet image formation method using same
Provided is an ultraviolet curable inkjet ink and an inkjet image formation method that uses said inkjet ink. The inkjet ink can be ejected from an inkjet head without being diluted by a solvent, has high photo curing sensitivity and produces high quality images with excellent weather resistance (smear resistance). The inkjet ink is characterized by a polymerizable compound which contains a maleimide compound having a chiral group and a compound selected from a vinyl ether compound and a N-vinyl compound.
1. An ultraviolet curable inkjet ink comprising at least a polymerizable compound, wherein the polymerizable compound contains a maleimide compound having a chiral group and a vinyl ether compound, and wherein the maleimide compound has an asymmetric (chiral) carbon atom located at the first or the second position from a nitrogen atom of the maleimide.
2. The inkjet ink of claim 1 , wherein an equivalent ratio of a maleimide group in the maleimide compound to a vinyl group in the vinyl ether compound is in the range from 70/30 to 20/80.
3. The inkjet ink of claim 1 , wherein the maleimide compound is represented by Formula (1):
wherein R 1 and R 2 each represents a hydrogen atom or an alkyl group having carbon number of 1 to 6 and may form a ring, Y 1 and Y 3 represents a divalent organic linking group with combination of a group selected from alkylene group, alkyleneoxy group, phenylene group, ester group, ether group or thioether group, Y 2 represents a divalent group having an asymmetric carbon atom, Z represents a n-th valent linking group, n represents an integer of 1 to 6, n1 represents 0 or 1, and n2 represents 0 or 1.
4. The inkjet ink of claim 1 , wherein the maleimide compound and the vinyl ether compound have two polymerizable functional groups in a molecule.
5. The inkjet ink of claim 1 , wherein a molecular weight of the maleimide compound is in the range of 200 to 1,000.
6. The inkjet ink of claim 1 comprising a photo initiator.
7. A method for forming inkjet image by utilizing the inkjet ink of claim 1 .