Can I use T6641 ink instead of T7741

[Ink stained Fingers]

How does Epson's ink numbering system work?

I don't know for sure - and Epson may not be willing to explain that in detail, but when I look to the inks for the tanksystem printers - ET.... and L.... I see this scheme - there is a base number like T664 and a suffix for the colors 1 for black and 2, 3, 4, ... for the colors , and it's all the same type of ink - all dye or all pigment , the T542 inks for the ET5850 are all pigment inks. if they mix dye and pigment you get a T105 for a pigment black for the ET7750 and T106 inks as dye inks for the ET7750, but beyond that you have the Epson article numbers which are longer and more complex, so take this just as an impression how it probably works.

 

[soysauce]

I don't know for sure - and Epson may not be willing to explain that in detail, but when I look to the inks for the tanksystem printers - ET.... and L.... I see this scheme - there is a base number like T664 and a suffix for the colors 1 for black and 2, 3, 4, ... for the colors , and it's all the same type of ink - all dye or all pigment , the T542 inks for the ET5850 are all pigment inks. if they mix dye and pigment you get a T105 for a pigment black for the ET7750 and T106 inks as dye inks for the ET7750, but beyond that you have the Epson article numbers which are longer and more complex, so take this just as an impression how it probably works.

Thanks for sharing that. It's interesting how Epson sometimes changes the numbers based on the region, and sometimes keeps them the same. For example the T664 inks appear to have the same T664 label numbers in North America and Europe ( T664120-S dye black in North America and C13T664140 in Europe), but the printers that take the T664 inks have different numbers in North America and Europe. However, the ET-7750 printer has the same number in North America and Europe, but uses 512 ink in North America ( T512020-S pigment black and T512120-S dye photo black) and 105/106 ink in Europe ( C13T00Q140 pigment black and C13T00R140 dye photo black).