Saujanya Exports

How are Fast Bases used in Textile Industry?

What Are Fast Bases?

Fast Bases are a type of base dye that is used in the textile industry. Bases dyes are a type of organic bases that are a kind of dye themselves or they can become dyes when combined with acids to make salts. They are called fast bases due to their characteristic of possessing excellent fastness properties.

Fastness refers to the property of any material being able to resist any change in its colour characteristics as well as the transfer of its colour to other materials. Basically, fastness refers to the ability of any material to resist the fading and bleeding of its colour.

Properties of Fast Bases

  1. Fast bases possess a high degree of light fastness. Light fastness means the duration and degree to which a material can resist the fading and reduction of its colour against light exposure.
  2. Fast bases are known for their vibrance and beauty, the brightness of their shades and their overall fastness.
  3. Fast bases are quite sensitive to heat and moisture.
  4. They need to be stored in a cool dry place at all times.
  5. They are freely soluble in water.

Types of Fast Base Colours

The following are the variety of colours available in fast bases:

  1. Fast Garnet
  2. Fast Red
  3. Fast Scarlet
  4. Fast Orange
  5. Fast Yellow
  6. Fast Violet
  7. Fast Blue
  8. Fast Bordeaux

Each of these main types also has sub varieties like Fast Red R Base, Fast Red RL Base, Fast Red ITR Base or Fast Scarlet GGS Base, Fast Scarlet R Base, Fast Scarlet RC Base or Fast Blue B Base, Fast Blue BB Base, etc.

Azo Dyes

Fast bases are also known as azoic diazo components. These azoic diazo components are used as one of the components of making azo dyes. Britannica defines azo dyes as. “any of a large class of synthetic organic dyes that contain nitrogen as the azo group ‘―N=N―’ as part of their molecular structures”. Hence any dyes containing the functional group ‘―N=N―’ are called azo dyes.

Azo dyes are created using azoic diazo components [aka fast bases] and a coupling component. E.g. An aniline, which is a primary aromatic amine when treated with nitrous acid, produces a diazonium salt. This salt then reacts with the coupling component to transform into a dye, which is used to dye and colour materials. This dye is also an azo dye and can be used as direct and disperse colourants.

Azo dyes are one of the most popular and most used dyes in the textile industry.

Dyeing Process with Fast Bases

There is a process involved when dyeing using fast bases as they are used in creating other dyes. Therefore, this process can be carried out by anyone ranging from home dyers to fast, base manufacturers themselves.

The process is as follows:

Stage 1- The fibre is applied/coated/infused with naphthol. Naphthol is a phenol that is soluble in alkaline solution and is also substantive to cotton, especially in the presence of salts.

Stage 2- After the fibre/material is coated with naphthol, it is combined with a diazotized base or salt. An example of such salt would be azo dyes which are mentioned above. This combination happens at a low temperature which generates an insoluble dye molecule in the fibre.

The dyes formed from this process are one of the only types of dyes that can create colours like deep orange, red, scarlet and Bordeaux shades that too with properties like excellent light and washing fastness. The colours produced are bright.

Other Applications in Textile

A few applications of fast bases in the textile industry other than azo dyes include
  1. They are used in the production and creation of African prints and wax prints as well as many block prints.
  2. Fast blues and other fast bases are used to produce pigments.
  3. Naphthol dyes are useful for dyeing cotton, silk, and rayon, as well as being useful in the handloom industry for dyeing cellulosic fibres.

We at Saunjanya Exports are one of India’s leading fast base exporters and manufacturers. We produce, manufacture, and export fast bases and other products like food colors, dyes, pigments, and more.

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