Every region of India comes with a characteristics of technique of textiles that has perfected one particular class of dyes. For a buyer it poses a significant challenge to maintain the quality of fabrics over time as each class of dyes has its own strength and limitations.
All over in south and in Bengal, Napthol colors are used to dye Ikats and Cottons. Generally vat colors are used to dye the dull shades. However, to achieve the required saturation in the darker shades, napthol colors are used. Due to process restrictions and the conditions when dyeing locally, the colorfastness to rubbing is a big problem when working with these colors. A case needs to be pointed out in this regard. When asked about the colorfastness issue for a certain sari from a vendor, it was found that even after washing the yarn after dyeing and washing the fabric after weaving, the colorfastness to rubbing was not improving for napthol dyes. Napthol colors are also being used in Maheshwari Saris for red and other dark colors.
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Vat colors are the most commonly used colors all across the country in dyeing traditional fabrics. Vat colors are easy to apply, the process can be done at a temperature achievable in the open furnaces. The colors are fast to rubbing and washing. The main issue is in the achieving of bright and saturated shades which vat colors cannot produce using ordinary condition.
Sulphur dyes are often used to dye black. Cheaper and easy to apply, they have a very good colorfastness to washing. The drawback is that the fabric starts to tear after a prolonged storage.
Reactive colors are increasingly being used in woven yarn dyed stripes and dobbies, thanks to the chambers used in dyeing hank yarn. They have good colorfastness properties overall.
Direct dyes are used extensively in the Indian traditional textile industry. These are easy to apply and cheap. Almost all the tie and dye fabrics whether, Bandhni, Lehariya, Mothra, Ikat and Shibori have these dyes. These are also being used in the Tussar/Viscose blends in piece dyed form. The colorfastness to washing is good or acceptable but to that of rubbing is poor. A challenge for a bulk buyers of the fabric of these dyes is to convert the dyers to reactive or vat dyes.
Acid/Metal Complex Colors
These are used in pure silk and wool. They pose no problems for the buyer. These are colorfast to washing and stable to fading.
Natural Dyes are obtained from plant extract. The problem with natural dyed fabrics is that the volumes cannot be obtained and quality is not consistent. Patchiness, tonal variation across the length and listing ( Center to Selvedge variations) are some of the defects that come naturally with natural dyes. Also the choice of colors is limited to a very restricted pallete; beige, black, maroon, mustard, rust, green and indigo are the colors that can be got in these dyes. Color fastness is a big issue with these dyes. These are often sold in the market with the disclaimer tag.