by ervhio » Fri Mar 13, 2015 11:56 am
My hypothesis: when stiff cotton is wet, it has a slight tendency to stick to itself, and the enclosed space of a washing machine, especially with the pressure of other clothes, can cause it to stay stuck in the same way for the duration of the cycle. Fabric has a greater tendency to lose dye along creases (e.g. raw denim), and if the pants stay creased due to the aforementioned mechanism, the abrasion of the machine and other clothes will assist in dye removal along those creases.
Proposed solution: wash inside-out; if issue persists, continue to wash inside-out, roll a bath towel (or two) lengthwise and insert into legs to prevent creasing.