US Patent 7647869 Method of making marking structure for printing multiple inks

A multi-ink marking structure for a hand stamp is made. A unitary foam member is provided and has a front surface, a rear surface and peripheral edges extending between the front surface and the rear surface. Selected locations of the foam member are sealed to form a barrier which extends at least substantially between the front surface and the rear surface and which divides the foam member into first and second regions adapted to store first and second inks, respectively. The barrier remains permanently connected to the first and second regions of the foam member. The barrier is adapted to prevent migration of inks between the first and the second regions. Print patterns are defined at the front surface.