Vertical Banding or Grain

We have had trouble with 'solid color area’s' streaking (vertical) on Korographics Abaco Beach and Dreamscape Suede. We are printing a dominate green solid with circle patterns. Because it is across 2 different materials that tells us it may be a heat issue or at least printer related. Have you come across this before? Even if you have not, would you have advise for us? See image

Hi digitalGuy, Which printer do you have?

HP Latex L28500 is what these came off of.

Hi digitalGuy, Vertical banding is a IQ issue related with the temperature. All the information related with troubleshoot print-quality issues related with vertical banding are explained on the User Guide (Chapter 13; page 130 on English version). Even though, let me provide you some advises: I will recommend you to print using the HP Certified profiles for your medias in case they exist. I know that for the medias that you are using, there are some HP Certified profiles. You will be able to find them at HP Media Solutions Locator. Pre-warm the printer. Results are always better when the printer temperature is stable that is why usually worse with the first plots. Load the substrate in the second/centre position to maintain more stable temperature along the substrate. Decrease dryer temperature to minimum possible. Increase the number of passes. Use the inter-swath delay thru the RIP or front panel. Activate the “Vertical correction” feature by front panel (Options > Ink > Image-quality maintenance > Vertical correction). Once you fixed the problem of the vertical banding I will recommend you to disable this function for other jobs. I hope this helps

FDC banner. L2550. Tried many different profiles (all downloaded from HP site). HP/Hep/Optima...Been having the issue for a while. ONLY on banner, wraps print perfect. HELP

Hi spotman, After review the picture attached we can see that you are suffering plasticizer migration on your banner substrate. Plasticizer shows up as randomly non-uniform areas with “coalescence like” graininess and increases the visibility of pinchwheel marks. Find below some recommendations: The only way to remove plasticizer is to “wash it out” with isopropyl alcohol. This is not practical for printing but can be used as a diagnostic tool: by washing only part of the substrate the defects can be made appear (not washed areas) and disappear (washed areas). Change printing material or, at least, the production batch of the material used (preferred the ones that have not been stored for a long time). In some cases, increasing heater temperature and number of passes can reduce the effect. I hope this helps. Best regards,

Hi Spotman, Let me know if this recommendations have helped you. Regards.