The definition of special color denim:
Because of the super deep indigo or indigo dyed denim clothing made by washing after processing, can obtain the special effect of bright color bright, widely welcomed by consumers. "Super indigo denim dyeing" has two major characteristics: the depth of dyeing and washing fastness especially deep especially good.
The former refers to the unit mass of yarn dyed indigo dye on the amount of (usually accounted for% of the dry weight of yarn dye, dyeing depth referred to as%) in particular, such as conventional denim warp indigo dyeing depth from 1% to 3%, while the "Indigo" dyeing depth need to reach more than 4%, it can be called super indigo blue or indigo. The latter refers to the "super indigo" dyeing jeans need to withstand repeated washing 3 hours or more, the color can still reach or exceed the conventional dyeing denim without color depth and color of the ground, than the conventional dyeing denim Nongyan much brighter. The indigo dyed denim washing fastness, its essence is depends on the degree of dye penetrating core yarn, rather than dye itself (Indigo wash fastness wet fastness is only 1, namely core penetration degree) better, better wash fastness. In the past the so-called "Indigo quick washing process, is actually in the yarn dyeing process, make the indigo dye on the fiber core penetration degree is very shallow, such as cowboy clothing wash processing, a thin layer of dye yarn surface is ground, white yarn exposed more quickly, so the color fades a short time after washing, so as to achieve the effect of fading, immediately. The super indigo dyeing is the opposite, dye core penetration degree requirements are particularly good, can make the wash denim garment processing, get deep thick and bright color.
Because of the "super indigo dyeing depth" dyeing dyeing denim products increased by more than 60% than traditional denim, indigo dye concentration therefore have increased, even reached 3 ~ 4G / L, it is possible to obtain a deep colour. This liquid viscosity increases, poor liquidity and influence of penetration ability of leuco dyes, the color fastness of washing of denim garment production decreased, not up to the demand for the final depth. So some companies will take again increase the design depth of dyeing, the dye indigo concentration increased again, permeability becomes worse, so to form a vicious spiral, is still not up to the requirements of "super indigo color". The higher the concentration of indigo dye, dyed red is heavier, more color gray, there is no "Indigo" effect.
Therefore, there are many production plants have been or are preparing to transform the dyeing equipment, with a number of ways to increase the number of dyeing to solve this problem. For example, to increase the number to 8 staining, even 10, not only the investment cost and dyeing material consumption increase, operation difficulty increases, and the increase of environmental pollution. A good method to resolve this contradiction, appropriate to reduce the proportion of insurance powder or caustic soda, especially caustic soda, the liquor pH stability in 11 to 12, the highest rate of dyeing and color stability, and appropriate to reduce the tension of warp dyeing piece, so as to obtain the "Indigo" good dyeing effect.
The above content is reproduced from MEYIDALE CLOTHING