Hello - this is my first post - I hope it is in the right forum.  I am a textile artist and I want to use thickened bleach to screen print onto fabric (the fabric has been dyed with indigo and I want to selectively remove the colour to create a pattern).  I have a small quantity of a product called Bleach thickener produced by the Jacquard company (for textile artists), and it works very well.  The jar doesn't say what the chemical composition of the product is.  I will run out of this soon, and it isn't available in Australia. I am looking for something else that will do the job.  I have tried cornflour (I think Americans call it corn starch?) but no matter how thick I make it once I add the bleach it breaks down - which is in accord with what I have read about bleach and organic materials not being compatible.  The only other suggestion I could find is to add Cab-o-sil.  I have no idea what that is, whether it would work, or if it is dangerous (I know not to mix certain things with bleach as it produces a nasty gas).  Oh, and in case you are wondering I do know that bleach will destroy the fabric, if left in long term.  As soon as I achieve the degree of dye discharge I want - usually about 15-30 mins I put the fabric in a bleach neutralising solution for 20 minutes, then wash thoroughly. Some people have suggested using the ready made thickened bleach gel you can get in the supermarket, but  most of those brands aren't available here, and those that are aren't thick enough for screen printing purposes.  thank you for taking the time to read this and perhaps make useful suggestions.

Try some Kaolin.

This is used as an inert thickener in several industries, is white(ish) non staining and may be available from you local pharmacist (without the morphine).

Thank you - I will give that a go.

You could take a look at thickening agents for cleaning products. A variety of chemical stores sell them and you would need to look at thickening agents stable at high pH and stable in presence of oxidizing agents. They could be e.g. cellulose fibrils, magnesium aluminium silicates or other agents (often not disclosed).

Edited April 11, 20187 yr by CharonY

9 hours ago, CharonY said:

magnesium aluminium silicates or other agents (often not disclosed).

'Yes reminds me of waterglass'

This may be thick enough for you.