Colour & Pattern in Fabrics

Acid dye -> used in an acidic dye bath, soluble in water, good fast to light.  

Direct dye ->  Soluble in water, moderately fast to light, poor wash fastness

Reactive dye -> water soluble, forms strong chemical bond with cellulostic and protein fibres. give bright colours, fast to washing (don't fade)

VAT dye -> not soluble in water, excellent wash and light fastness, best known vat dye is 'indigo', used to dye jeans. 

Colour fastness is whether a fabric fades or not, factors affecting colour fastness of textile products are: 

• bleaching
• washing
• dry cleaning
• rubbing 
• light
• perspiration
• perfume