I have previously used avocado pips in a high pH bath to produce pinkish colour on cotton.
This time I wanted to explore the effect of variations in dyeing conditions. The conditions that we know affect colour are, inter alia, time; heat; pH and mordants.
Standard throughout this study was a cotton damask tablecloth that had been mordanted in soy milk. The tablecloth was given to me by artist friend Liz Arnold (http://www.lizarnold.com.au).
The soy milk was made as described in a previous post (see note 1 below).
I made the avocado pip bath by placing 12 frozen pips in 20 cups of Perth (Western Australia) tap water. I then added 2 tablespoons of soda ash to that bath and turned on the heat.
After 30 minutes I added two pieces of dry soy soaked damask fabric to the bath and simmered them for 20 minutes. They were then removed, allowed to air dry and then rinsed and washed.
I hypothesised that leaving the fabric in the bath for a longer time might increase the depth of colour. Moreover, I figured that the actual bath itself might increase in strength over time. So I added two more pieces of the same soy-mordanted damask cotton to the same bath a day later, brought it to a simmer, turned it off and allowed it to cool, then repeated this regime twice more. This took a day and a half by the time I got to the pot again but had involved minimal gas as I had turned the hotplate off each time the bath started to simmer.
The result was a much darker colour in the fabric. The master of soy milk fabric preparation (see note 2 below) tells us that soy milk cures over time. He suggests that up to three months can be left before washing a dyed piece. I so wanted to wash my pieces! However, I decided to wait……………………
Three days later I was over waiting. So I washed one of the two pieces of fabric, dried and ironed it. That tided me over for another week. Then I weakened and washed the other one.
It does seem that the dye bath developed its colour over time and yielded a more saturated result after a couple of days.
It is also clear that a gap of three days or ten in washing a dyed piece makes little difference to the depth of colour. By the way, the strong marks in the fabric seem due to extra dye take up. In some cases, as with the marks at the bottom of the middle piece above, that was due to pooling around a crease. In other cases it might be due to pre-existing stains in the former tablecloth. They don’t worry me. In fact I like them. Since I will be using them for fabric collage the more variations and textures the better!
Ever the pseudo scientist, I then decided to use the same dye bath, now verging on elderly, to test some other hypotheses.
- What if I put unmordanted damask cotton in the bath?
- What if I put silk unmordanted fabric in the bath?
Prediction: The unmordanted damask cotton will be paler than the mordanted one. The silk will be darker than the unmordanted cotton and perhaps the same or better than the mordanted cotton.
Finally, because this avocado pip bath seemed to be capable of keeping on giving, I tossed in a piece of silk from my stash and a piece of cotton sheeting. All unmordanted.
I expected the piece of silk, albeit unmordanted, to respond well to the now mature and rich dye bath. I was a bit disappointed so I ripped it in half, saved one piece for comparison, and re-immersed the second half for a day. The cotton sheet piece picked up a lot of colour. The second piece of silk also picked up more colour.
Overall, I am pleased that I have developed a range of cotton fabric in different rosy shades for future work as well as gaining the confidence of getting this good colour in future out of avocado pips. Cotton is such a challenge to dye naturally without harsh things like iron.
Next challenge: some fresh mulberries a friend has left on my front porch!!!!
Note 1: (https://wordpress.com/post/mnfblog.com/3799).
Note 2: (http://johnmarshall.to/H-Soymilk.htm accessed 22 Oct 2018 and 3 Dec 2018)