FABRIC PREPARATION

Preparing your T-shirt

SCOUR/WASH

It means the same thing, wash first.  Why? there are natural substances, and additives from the milling process, that protect the fabric, however they can prevent the mordant and dye from bonding. For cotton T-shirts a hot wash in the machine with a spoon of baking soda will do the trick

MORDANT or BINDER

A mordant creates a chemical bond between the fabric and the dye and provide the best colour fastness.  Alternatively, for a mechanical bond, use a binder so wearing and washing will gradually see a

change to the colour but it will last for several years.  Depending on what mordant or binder you use you may need to rinse or rinse & dry or just dry and store your T-shirt before dyeing.  I have been using a soya milk binder as it is natural, cheap and easy to buy and there is no rinse stage.

RINSE

If you have used a mordant then rinse carefully to remove any unattached mordant; this can be done under running water or by swilling in a bowl.  Either dry for using later or dye straight away – soaking dried fabric before dyeing is essential for the most even take up of colour.  

Keeping it easy with cotton T-shirts – you could also use cotton shirts, cotton fabric that you then sow (including calico and muslin) or linen, hemp and bamboo fibre.  Prewashing fabric lengths is essential – for example calico can shrink by 10% on the first wash: for all those dressmakers out there, this is your reminder to wash first before measuring twice and cutting once! 

Keeping it simple – we stick to using white cotton T-shirts for all our dyeing information - wool and silk (protein-based fibres) need different dyeing methods and ingredients even when using the same dyer’s plants

We have used cotton T-shirts as they are easy to get hold of and relatively inexpensive: and with the time involved there is a lot to be said for the final stage to be the convenience of dye, dry, wear.  Just remember that the thread on ready-made clothes is normally synthetic polyester which will not take up any dye, if you are making clothes to dye and want the thread to dye too you will need to sow your garment with pure cotton thread before dyeing.  I have been caught out by a purchase of cotton Broderie-anglaise – stitched with polyester thread – I ended up with a green and white top because I assumed the thread was also cotton!  It is a matter of personal taste but most of the time the undyed thread makes for a fine white detail about the hem, sleeves and neckline that I can live with! 

Check the labels that you are not caught out by poly-cotton, this fabric is a cotton including synthetic fibres which will not take up the dyes, it is unsuitable to use. 

Soya Milk Binder

Remember that soya milk is a binder not a mordant.  The clothes I have dyed are mostly pretreated with soya milk… I either handwash them with cool water or use a delicate machine cycle with eco detergent: I also enjoy the gradual changes that take place over time… and I can re-dye should I wish to. You can also add a tannin which can develop deeper colours when you dye.  You can make your own soya milk but for convenience I buy it!

• Pre-soak your T-shirt in warm water for at least two hours
• Mix 1 litre soya milk (unsweetened & unflavoured) with 4 litres water stir well (add any tannin at this point) then add your pre-soaked T-shirt, put in a cool place for 12 hours with an occasional stir.  Wring out and hang to dry (keeping the soya milk mixture)
• Now dip your fabric back into the soya milk, stir for a couple of minutes to make sure it is thoroughly coated, wring out and dry (keeping the soya milk mixture!)
• repeat the soya milk soak and dry 3 or 4 times in total, after the final dry it is best to leave the fabric for a week before dyeing to achieve the best take up of dye. 

Aluminium lactate Mordant

This is a newer mordant, I quite like this as it is made from the by-products of the sugar industry, maize or starch derivatives.  Please BE AWARE that aluminium lactate is a fine powder, you will need to weigh it carefully and you should use a mask when weighing and gloves when necessary

• You need 7%-10% of aluminium lactate to the Weight Of Fibre (often shown as WOF).  You need to weigh your fabric when it is dry and use the following calculation:
• weight of fabric in grams divided by 100 them multiplied by 7 = weight of aluminium lactate
• Pre-soak your T-shirt in warm water for at least two hours.
• Half fill your dye pot with hot tap water and add the measured amount of aluminium lactate and stir well, the warmth from the hot tap water should be enough and no additional heating ought to be needed.
• Add the wet cotton and, wearing gloves, squeeze it a few times and swirl is gently. Leave overnight if possible before wringing out (wearing gloves for this too).
• Wear gloves to rinse carefully to remove any unattached mordant: this can be done under running water or by swilling in a bowl.  You can now dye your fabric straight away or dry it for using at another time.

The next stage is preparing your dye – this information is being included with each dyeplant’s details… as soon as I can get my notes written up and added, one at a time, I am getting there slowly.