Ink compositions and methods for making the same

A method of making an ink composition, comprising:

• providing an ink vehicle including:
• a solvent system present in an amount ranging from about 10.0 to about 20.0 wt %, wherein the solvent system includes a betaine solvent and glycerol, 2-pyrrolidone, or a combination thereof;
• at least one surfactant present in an amount ranging from about 0.0 wt % to about 10.0 wt %;
• at least one polymeric binder present in an amount ranging from about 2.0 to about 6.0 wt %;
• and
• water;
• and
• adding an effective amount of a pigment to the ink vehicle.

A method of forming an image on a substrate, comprising:

• providing an ink composition including:
• a solvent system present in an amount ranging from about 10.0 to about 25.0 wt %, wherein the solvent system includes a betaine solvent represented by the formula (R3)N+—CH2—COO− and glycerol, 2-pyrrolidone, or a combination thereof, wherein R is CH3;
• at least one surfactant present in an amount ranging from about 0.0 to about 10.0 wt %;
• at least one polymeric binder present in an amount ranging from about 2.0 to about 6.0 wt %;
• water;
• and
• a pigment;
• and
• establishing the ink composition on at least a portion of the substrate.

An ink composition, consisting essentially of:

• a solvent system including an effective amount of a betaine solvent and an effective amount of glycerol, 2-pyrrolidone, or a combination thereof;
• an effective amount of at least one surfactant;
• an effective amount of at least one polymeric binder;
• water;
• and
• a pigment.