Water-soluble, non-toxic resist made in France where they really know the silk painting business. Rinsing the fabric in warm water removes resist lines. This one is steamable, so can be used with professional silk dyes, and has excellent resist properties for a water based product.
Note: This resist is steamable and works better with steaming than other water-based resists, but even so, once the resist is subjected to the prolonged high heat of steam-setting it changes the composition of the resist and can make it really stick to the silk and hard to wash out. The best thing you can do is GENTLY scrub with a SOFT toothbrush over the lines during the washing. It doesn't always work. If you use silk dyes and don't want to deal with resist not washing out you can use solvent-based gutta and then dry clean it out, or use colored water-based resists that you leave on the fabric. Water-based resist does wash out easily if you use a silk paint rather than a silk dye because the paint only requires ironing to heat-set.