random bleeding of dye

[Jan Vuori <Jan_Vuori@xxxxxxxxx>]

Hello,

I am posting this on behalf of a quilter. The problem is random bleeding
of colour in some quilt blocks that she has already spent a considerable
amount of time working on. She prewashes her fabrics in cold water with
vinegar. This is followed by rinsing. If the colour runs she continues
rinsing until the water runs clear. She has used this method for many years
working with fabrics from a variety of sources and has never before encountered
problems with the dye bleeding randomly afterwards.

 
In this instance she used "Easy On" spray starch on a few colours
to facilitate working with small pieces. Then she washed the quilt blocks
in cold water to remove the spray starch. Upon final drying some dye bled
from the cranberry and some similar colours but only in random areas. There
was no correlation with fabrics to which spray starch had been applied
and seemingly no correlation with any other factor (such as thickness of
fabric). 

She was able to remove  much of the dye bleed by further washing in
cold water but had to take apart some of the blocks to replace areas that
remained stained or to prevent further staining

Does anyone have an explanation for the randomness? 

Any suggestions to prevent this from happening again?  

Jan Vuori
Senior Textile Conservator
Canadian Conservation Institute
1030 Innes Road
Ottawa Canada K1A 0M5
tel:  613 998-3721
fax: 613 998-4721
www.cci-icc.gc.ca