US 7,491,266 B2
Black ink and ink set for inkjet recording
Toshiki Taguchi, Tokyo (Japan); Naotaka Wachi, Shizuoka (Japan); and Manabu Ogawa, Shizuoka (Japan)
Assigned to FUJIFILM Corporation, Tokyo (Japan)
Appl. No. 10/578,229
PCT Filed Nov. 04, 2004, PCT No. PCT/JP2004/016697
§ 371(c)(1), (2), (4) Date May 04, 2006,
PCT Pub. No. WO2005/042652, PCT Pub. Date May 12, 2005.
Claims priority of application No. 2003-374328 (JP), filed on Nov. 04, 2003; and application No. 2004-003813 (JP), filed on Jan. 09, 2004.
Prior Publication US 2007/0101899 A1, May 10, 2007
This patent is subject to a terminal disclaimer.
Int. Cl. C09D 11/02 (2006.01)
U.S. Cl. 106—31.27  [106/31.46; 106/31.48; 106/31.5; 106/31.52; 106/31.57] 12 Claims
 
1. An ink set for inkjet recording, which comprises at least two black inks having different densities from each other, wherein the at least two black inks each independently comprises: an aqueous medium; and a dye having a λmax of from 500 nm to 700 nm and a half-band value of 100 nm or more in an absorption spectrum of a diluted solution, the absorption spectrum being standardized to have an absorbance of 1.0 at the λmax,
wherein
a lower density black ink in the at least two black inks has an ozone fastness stronger than that of a higher density black ink in the at least two black inks, the higher density black ink having a density higher than that of the lower density black ink.