Grand format Dye sub blue prints turned purple after 3 months

[gridor]

Morning everyone,

First time poster on here, I have recently had an issue with some dye sub prints that have been installed. the prints are mainly blue but after 3 months they have all gone a purple colour. Im direct printing on a reggiani 340 with a klieverik applying the heat and everything seemed good as they left us and went up, i have had no similar complaints from anyone else. I'm wondering what you think may of caused the colour shift, undercooking and the ink washed out, the job was up on an external south facing wall so had the sun all day causing it to over cook perhaps.

these are printed on a stretch material, let's say 3m wide and 2m high to give you an idea of size, branded inks, same process as always and we print a lot of this material so it's not a new process for us.

Any thoughts appreciated

 

[SteveSuffRIT]

Sounds like ultraviolet (UV) in natural sunlight is burning out (fugitive) the yellow colorant, dye.
Is your printer colorants lightfast for outdoor usage, 72 hrs of exposure is typical.

 

[gridor]

Yes these are the OEM inks from EFI so should be suitable for anything, these are the same inks we use for flags and haven't had issues there either. But when i say haven't had issues i mean we have not had a bunch of complaints come in. anything we have had up for testing over the years still looks correct so I'm hoping this is just an anomaly but am interested in possible causes.

 

[SteveSuffRIT]

Print out a 100% solid yellow patch, cover half of it with something opaque (aluminum foil), put it in a sunlit window and look at it covered section once a week.

 

[gridor]

Print out a 100% solid yellow patch, cover half of it with something opaque (aluminum foil), put it in a sunlit window and look at it covered section once a week.

Oh i like this, not sure why i didnt think of it, i will do this thanks.