We get mordant questions all the time at Botanical Colors so why not create Mordant Monday??? Got mordanting questions? Email [email protected]
YOU ASKED: I use fresh rhubarb leaf for pre-mordanting wool, and I’m wondering if it can be used dried, and if so, what is the ratio of dried leaf to WOF?
KATHY ANSWERED: Since you are already using the fresh leaves, do you have a percentage or weight that you are using? If so, I would use about half as much with dried leaves and see if you like the results!
YOU ASKED: Kakishibu Japanese persimmon dye is used with tin (Stannous chloride) as a mordant or additive on cotton. Boutrup and Ellis have a recipe for a tin mordant on protein fibers at 3% WOF + 6% cream of tartar but I haven’t found anything about using tin on cellulose. I’m thinking to start of using the same proportions, do you have any recommendations?
KATHY ANSWERED: I have not used tin as a mordant with Kakishibu as the dye is a strong tannin that darkens on exposure to air and light and does not require a mordant. The information I found about tin and cellulose seemed to indicate that tin can weaken the cellulose structure which may be the reason why it isn’t used often.
YOU ASKED: If I’m using tannin and alum acetate to mordant my cellulose fabrics, is it necessary to fix the fabric with wheat bran or calcium carbonate after the tannin/AA steps?
KATHY ANSWERED: My understanding is that you do not need to do a post-bath as well but you can definitely run an experiment and see which results you prefer.