Patent ID: 7410245

Claim:
A method for applying an image forming composition to a pile fabric using a drop on demand ink jet printer, comprising the steps of: a. providing a drop on demand ink jet printer, comprising: 1. a reservoir; 2. a nozzle orifice; and 3. a valve for regulating the flow of ink from the reservoir to the nozzle orifice, the valve comprising: i. a plunger member journalled for axial reciprocation between a rest and an operative position within a tubular member supporting an electric coil under the influence of a magnetic field generated by that coil when an electric current passes through the coil; ii. bias means to bias the plunger towards its rest position when no current is applied to the coil, the distal end of the plunger extending into a valve head chamber having a outlet bore to a nozzle orifice, the reciprocation of the plunger being adapted to open or close a fluid flow path from the valve head chamber through that bore to the nozzle orifice; and wherein, the plunger is made from an electromagnetic material having a saturation flux density from 1.2 to 1.8 Tesla, the bore leading from the valve head chamber to the nozzle orifice has a length to diameter ratio of 5:1 or less, and the nozzle orifice has a diameter of 80 micrometers or less; and b. operating the printer at a drop generation frequency of at least 1 kHz.