Patent ID: 9556357
Date: 2017-01-31
CPC Classifications: B41J,C09D

Claim:
1. An ink composition configured for use in an ink jet recording apparatus having a nozzle for ejecting the ink composition and a suction cap that seals the nozzle, the suction cap defining a cap space that includes an ink absorber therein, and the cap space is configured to be evacuated when the suction cap seals the nozzle, the ink composition comprising: a pigment, a content of the pigment being equal to or greater than 5.0 mass %; acetylenediol having an HLB of less than 4, a content of the acetylenediol being 0.010 mass % to 0.40 mass %; a 1,2-alkanediol having 4 to 6 carbon atoms, a content of the 1,2-alkanediol having 4 to 6 carbon atoms being 0.50 mass % to 6.0 mass %; and an anionic surfactant, a content of the anionic surfactant being 0.025 mass % to 0.25 mass %, wherein a mass ratio of the acetylenediol to the anionic surfactant is 0.30 to 4.0, a mass ratio of the acetylenediol to the 1,2-alkanediol is 0.0010 to 0.100, and wherein during evacuation of the suction cap when the suction cap seals the nozzle, the acetylenediol having the HLB of less than 4 reduces the formation of bubbles in the ink composition that collect on the ink absorber.