Back to results
US 7,922,315 B2Granted
Inkjet ink and printing method using the same
AssigneeGeneral Company Limited
InventorKozo Isobe
Life of this patent
Estimating the term…
Abstract
Disclosed are an inkjet ink and a method for printing on hydrophobic media such as offset coated media using the inkjet ink. Specifically disclosed is an inkjet containing a pigment, water and a surfactant which is characterized by also containing 40 to 75 weight % of a polar non-protic solvent with a molecular weight of 40 to 130 which has permeability to a hydrophobic surface such as the coating of an offset coated medium. Such an inkjet ink enables better printing on hydrophobic media such as offset coated media than the conventional inks.
Claims19
An inkjet ink for printing on hydrophobic media, comprising:
- a pigment;
- water;
- a surfactant having a dynamic contact angle of no more than 20°, the dynamic contact angle being an angle formed by a droplet of a 0.1% aqueous solution of the surfactant and a substrate surface of a stainless steel SUS 304 as measured, 300 ms after contact of the droplet with the substrate surface upon dropping the surfactant solution onto the substrate surface under an environment having a temperature of 23° C.;
- from 40 to 75 weight % of a polar aprotic solvent having a molecular weight of 40 to 130, and
- at least one of an acetylene glycol and a glycol ether, and
- at least one ethylene oxide adduct of ammonium citrate expressed by Formula (4):
- where M1, M2, and M3 may be the same or differ, with each of M1, M2, and M3 indicating sodium, potassium, or other alkali metal, the ammonium group, or hydrogen, but with not all of M1, M2, and M3 indicating hydrogen at the same time, and n indicating a numeral from 1 to 28.
4 more elements
Dependencies are inferred from the claim text.