When handpainting dye on fine fabrics such as silk, a strong line of resist or gutta can be used to control the flow of dye and keep colours separate. The resist line must penetrate to the reverse side of the fabric and all lines must connect solidly and dry completely to form a strong barrier. Like in a stained glass window a sharply defined border to the areas of colour is achieved. The resists that produce these lines are clear or coloured, water based or solvent based and can be applied using a squeeze bottle with nib, pipette, silkscreen, brush or air pen. Care should be taken when applying dye. Pooling of excess dye or vigorous brush action can break down the barrier. Allow dye to travel naturally and gently to the resist line.
Tip: Hot wax as used in Batik is the strongest resist for this purpose but its strength is offset by complications in removing the wax from the silk after dyeing.