XJ128 and XJ128 Plus Printhead
XJ128 Guide to Operation
Xaar Document no: D031010302 Version A
Page 43
8 Maintenance, Reliability and Lifetime
8.1 Printhead maintenance
Printhead maintenance plays a central role in the performance and reliability of the XJ128
printheads.
The XJ128/200 and XJ128/360 printheads fitted with the non-wetting coating (NWC) will require a
different approach to the maintenance strategy adopted than that required for the XJ128/200 Plus
printhead.
As the XJ128/200 Plus printhead utilises a
‘
wetting
’
nozzle plate
, it is crucial that the
printhead is operated with a thin film of ink always present on the surface of the nozzle
plate. This ensures that the printhead will operate reliably over time and across the
range of operating frequencies. When maintaining the printhead, ensure that the
nozzle plate surface is not wiped dry, in order to achieve reliable operation.
8.1.1 Why printhead maintenance
Printhead maintenance is vital for a number of key reasons:
Printhead lifetime
Printhead reliability
Print quality
The extent and nature of the printhead maintenance will determine how the final system performs
with the printhead. The aim of a maintenance cycle is to ensure a few simple conditions for the
printhead.
The nozzle plate is clean of ink or debris
Any build up of air in the channels is removed
For the XJ128/200 Plus printhead, a thin film of ink remains on the nozzle plate
The extent to which these conditions can occur will depend upon the environment in which the printer
is housed, the workload of the system, ink type, media type and the maintenance strategies
employed to counter these effects.
8.2 Maintenance strategies
8.2.1 Operational maintenance
Operational maintenance is performed during operation of the machine. It is an automatic function of
the printing machine set to run at designated intervals, whilst running a job, to ensure reliable and
continuous printing. Depending upon the system a maintenance carriage may need to move into
position to perform the maintenance.