title: High-shear-rate capillary viscometer for inkjet inks.
abstract: A capillary viscometer developed to measure the apparent shear viscosity of inkjet inks at high apparent shear rates encountered during inkjet printing is described. By using the Weissenberg-Rabinowitsch equation, true shear viscosity versus true shear rate is obtained. The device is comprised of a constant-flow generator, a static pressure monitoring device, a high precision submillimeter capillary die, and a high stiffness flow path. The system, which is calibrated using standard Newtonian low-viscosity silicone oil, can be easily operated and maintained. Results for measurement of the shear-rate-dependent viscosity of carbon-black pigmented water-based inkjet inks at shear rates up to 2 x 10(5) s(-1) are discussed. The Cross model was found to closely fit the experimental data. Inkjet ink samples with similar low-shear-rate viscosities exhibited significantly different shear viscosities at high shear rates depending on particle loading.
authors.affiliation: FUJIFILM Dimatix, Inc., Lebanon, New Hampshire 03766, USA.
authors.forename: Xi
authors.initials: X
authors.lastname: Wang
authors.forename: Wallace W
authors.initials: WW
authors.lastname: Carr
authors.forename: David G
authors.initials: DG
authors.lastname: Bucknall
authors.forename: Jeffrey F
authors.initials: JF
authors.lastname: Morris