Ball-point writing instrument containing an aqueous ink composition
AssigneeThe Gillette Company
InventorsLaura K. Case, Chandrasen Gajria, Rachel M. Loftin, Henry Peper
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Abstract
Gelled, aqueous inks are used in conjunction with viscoelastic ink follower compositions to avoid the necessity of using a fibrous ink reservoir or a porous or extruded ink feed rod.
Claims13
A ball-point pen employing a liquid ink reservoir containing an ink having a viscosity less than 100 cPs at shear rates produced by writing and comprising a combination of ingredients consisting essentially of from about 50 to about 99% by weight of a polar solvent comprising at least 50 percent by weight water, up to about 30% by weight coloring matter, and sufficient water-dispersible gum or resin to provide a shear-thinning index of from 0.01 to 0.60 said reservoir including a viscoelastic ink follower having a composition which exhibits predominately elastic response at low frequency or shear rate and a predominately viscous response at a high frequency or shear rate.
Dependencies are inferred from the claim text.