Indigo Gives America the Blues, Timeline


Glucose Process: Late-1800s

Glucose Process: Late-1800s

Technological breakthrough:
Direct printing of indigo (the “glucose process”) that gave darker shades of blue than China Blue, the earlier method of directly printing indigo

What to look for:
Dark blue ground with crisp designs.
Caution: it is virtually impossible to distinguish between glucose process prints and resist or discharge prints.

Successful direct printing of a dark blue indigo finally was achieved with what was called the “glucose process.” The new method could produce inexpensive dark indigo prints that the China Blue method could not achieve.