Application of natural dyes

Dyeing can be carried out at any of the following stages in the textile manufacturing stage:

        i.            The fibres can be dyed before they are spun. Fibre dyeing provide a deep penetration of the dye into the fibre, giving even color and excellent color fastness.

      ii.            The yarn can be dryed after spinning

    iii.            Fabric can be dryed (piece Dueing). In cross dyeing(one stage blend dyeing) fabrics od two or more fibres can also be dryed so that each fibre accepts a different color, through the use of appropriate dye for each fibre.

    iv.            It is essential for the correct identification of the fibre or fabric to be made before drying starts.

Natural dyes         click here

Types of textile suitable for natural dyeing          click here

Application of natural dyes      click here

Dyeing of cotton with mordant dye(alizarin dye)

The dyeing procedure of cotton with mordant dye(alizarin dye) is describe below:

            i.            At first cotton fabric is boiled in the solution of

Ø  1 part TR Oil &

Ø  10 part water for 12 hours.

          ii.            Then the fabric is dried at 40-60°C

        iii.            Treated again with al-acetate at 60°C for 2 hours.

        iv.            Then dry at 40-60°C.

          v.            Again treated with 2 parts Na-phosphate and 10 parts water at 40-40°C for 40 min.

        vi.            1-1.5% dye ( on the weight of fabric) is added in the solution with ca-acetate at room temperature for 30 minutes.

      vii.            Then fabric is hot rinsed (at 70°C) for 30 minutes.

    viii.            Finally the fabric is washed with soap solution and water and then dried.

Mordant dyes         click here

Trade names of mordant dyes        click here

Properties of mordant dyes         click here

Classification of mordant dyes         click here

Method of application of mordant dyes         click here

Dyeing of cotton with mordant dye(alizarin dye)         click here

Production and processing of jute

The jute plant, Corchorus, is a herbaceous annual. It may grow to 5m (15ft), with a stalk diameter of 20mm. In India and Bangladesh, the plants are commonly harvested with a hand sickle.

Retting is carried out in a manner similar to that used for flax, the stalks being steeped in a sluggish stream of water. They are examined daily until the stage is reached at which the fiber can be separated easily from the stem. The strands of fiber, often as much as 2m long, are washed and hung up in the sun to dry. They are compressed into bales and sent off to the mills for spinning.

It is necessary to incorporate small amounts of mineral spindle oils into the fiber during conversion into yarn. Normal jute goods may contain up to 5 percent oil, but so-called ‘stainless’ yarns containing 1 percent of oil or less are commonly available when the jute is to be used for special purposes, e.g. cables, fuses, carpet backings, wall-coverings etc.

Jute fibre     click here

Jute producing area   click here 

Chemical composition of jute fibre    click here

Properties of jute fiber   click here

Features of jute fiber    click here

Jute gradation    click here

Factors affecting gradation of jute     clich here

Kutcha grading of jute     click here

Production and processing of jute     click here

Bleaching and Dyeing jute fibre      click here

End uses of jute goods       click here