Epson Stylus Pro 7890 Series Reference Manual page 13

Industry Defining Pigment-based Ink Technology
Dual-Black Ink Mode Technology
Two different black ink technologies can be used to optimize the black density for
virtually any media type
Photo Black ink can produce professional results on any media type, but is optimized
for traditional photographic papers
Matte Black ink can produce even better results on specific matte-type papers such as
Enhanced Matte, Hot Press and Cold Press Fine Art Paper, and many others
Matte Black Print on Matte Paper Photo Black Print on Matte Paper
Optimized Black Density
for any media type
Photograph © 2010 Greg Gorman