Abstract: An oily ink, wherein the oily ink comprises a pigment, a pigment dispersant, and an organic solvent, said oily ink comprising: 0.1 to 10% by mass, relative to a mass of the oily ink, of a nonionic surfactant having a HLB of from 6 to 16, wherein the nonionic surfactant having a HLB of from 6 to 16 is at least one selected from the group consisting of fatty acid esters, ethers of fatty acid esters, and polyoxyalkylene ethers.
Abstract: A paper feed unit for a printer to form an image on a print paper by an image former, the paper feed unit including: a paper feed tray that stacks print papers to be fed; a paper transfer route that transfers print papers; a register roller that is provided upstream of the image former in a paper transfer direction in the paper transfer route and holds a fed print paper to adjust a timing to transfer the fed print paper to the image former; a pick-up roller that transmits a print paper stacked in the paper feed tray to the register roller, the pick-up roller being smaller in width than a width of a print paper to be transmitted; and a regulator that comes into contact with a loose portion of a print paper loosened in a paper feed route in between the pick-up roller and the register roller.