Abstract: A recording apparatus having an ink storage body, an ink supply section, an ink jet head, and an ink composition, wherein the ink storage body has an ink pouring port through which the ink composition is poured and a liquid level display section displaying an ink liquid level of the ink composition stored in the ink storage body, the ink jet head is supplied with the ink composition from the ink storage body via the ink supply section and ejects the ink composition to cause the ink composition to adhere to a recording medium, and the ink composition is a water-based, red-based ink containing an azo-based pigment, an acetylene glycol-based surfactant A with an HLB value of less than 10 and an acetylene glycol-based surfactant B with an HLB value of 10 or more.

Abstract: An ink jet ink composition functioning as a water-based magenta ink includes an azo-based pigment and a 1,2-alkanediol having 4 to 8 carbon atoms. In the ink jet ink composition described above, the azo-based pigment has a volume average particle diameter D50 of 110 nm or less, and a content of the 1,2-alkanediol having 4 to 8 carbon atoms with respect to a total mass of the composition is 3.5 percent by mass or less.

Abstract: A water-based ink jet ink composition contains C.I. Pigment Red 150 and at least one of 1-(2-hydroxyethyl)-2-pyrrolidone and ?-caprolactam.

Abstract: An ink jet ink contains a pigment; an inorganic oxide colloid; a betaine; and water, and in the ink jet ink described above, a total concentration (mg/L) of potassium ions and sodium ions in the ink is 500 ppm or less.