HP 750 User Manual

Page 198

750C

Plus

755

9-20

Print Quality

C4705-90000

Corrective Actions

Plot in an interlaced print mode (Best) thus increasing the number ofpasses over the media.

Set the lightness to lighter" to reduce the amount ofink used. Increase the dry time to reduce

the migration in multiĆpass print modes.

Halo

Description

There is a white border between black and color area fills.

Causes

There is a reaction between the inks that changes the tensional forces at the edge, causing

the black ink to move away from the color.
This is also a common problem for all the CAD media types except the coated media.

Corrective Actions

Plot in an interlaced print mode (Best), thus increasing the number ofpasses over the media.

Banding

Description

There are repetitive bands in the area fills.

Causes

The following are the main causes of this problem:

D XĆaxis advance error: This error causes a variation ofhue between consecutive bands. The

hue is constant within each band. Nozzles are misaligned from one swath to the next.

D Cartridge nozzles out, weak or misdirected: These problems generate horizontal lines of

different color in area fills. In this case, instead of affecting the complete swath, the

problem is restricted to the particular nozzles that are failing.

In both cases, drop volume can help to hide the problems. A low drop volume makes the

problems more visible.

Corrective Actions

D XĆaxis advance error: Perform the accuracy calibration ' page 7Ć6. Ifthis does not fix the

problem, troubleshoot the XĆaxis system (mark position test ' page 8Ć44). Ifnecessary,

replace the XĆaxis motor ' page 6Ć25.

D Cartridge problems: Set the plotter to multiĆpass print mode. Replace the cartridges.

Check the wipers and caps ofthe Service Station and ifnecessary, replace the service

station ' page 6Ć42.

D Drop volume too small: Troubleshoot the pen thermal management system, the TTOE,

the carriage electronics and the cartridge.