What are non-toxic natural dyes?
Dyes own so much importance in our daily lives. Everything needs color to be distinguished and sometimes we prefer to give a color of our own choice to the things we want. For instance, if you want pink color fabric then you will get it to dye according to your own taste.
There are two types of dyes widely used some are synthetic that are made from a combination of chemicals and some are natural that are obtained from plants or animal extracts. Non-toxic natural dyes are those obtained from natural sources such as plants, animals or minerals.
Those extracted from plants come from woods, roots, barks, berries, lichens or flowers. And those obtained from animals come from shellfish or insects. Natural dyes are used in leather, textile, and other materials production industries.
Natural dyes have been used for so long in India and China during 2500 BC. Ancient civilizations have been using natural dyes for manufacturing and for trade purposes. Italian dyers were among the best of Roman times in the dyeing industry.
Non-toxic dyes are those with higher average absorption rate which means less water is required for them during the rinsing process. A low amount of dye is added in water which causes less environmental damages. Such dyes don’t contain heavy metals such as copper, zinc, and chromium and don’t need any mordants to fix them to the fiber.
Reasons to use Natural dyes:
Due to major environmental concern natural dyes are preferred because synthetic ones pose a serious threat to water and soil. Wastewater having dye in it is discharged into water bodies and any person who encounters this water is affected with skin diseases.
Natural dyes are used in aqueous solution and required mordant to fix on the fiber surface. Mordant is used because some dyes don’t have an affinity to attach with fiber so mordant act as a bridge to connect them. Aluminum sulfate or other metallic mordants are mostly used to affix dye on fabric. Mostly non-toxic natural dyes are of plant origin and there are roughly more than 500 plant species that are source for dyes.
The dyeing process is started by soaking dyeing stuff in water for several hours then provide heat to let it simmer for more hours to extract the dye. Let it cool and remove the dyestuff and rinse it with water. Contact dyeing is another method in which dyestuff along with mordants, rusty nails or copper wires are placed in a sealed plastic bag or glass jar that gives different patterns.
Natural dyes are eco-friendly and give vibrant, soft and lustrous colors. They are not only biodegradable but also non-allergic. They do not contain harmful and carcinogenic chemicals thus safe to use by humans. Natural dyes don’t produce toxic residues because it skips the whole production process used in synthetic dyes. That’s why causes less damage to water than synthetic dyes.
Just like dyes fabrics are also natural or synthetic, natural dyes cannot adhere to a synthetic surface. Fabric made from natural dyes provides high UV absorption thus by wearing such clothes you can be protected from harmful UV radiations.
Some natural dyes are found to have mutagenic effects such as safflower yellow leads to cancer and some other cause asthma problems. Natural dyes are considered renewable as they are obtained from renewable sources so does not deplete the non-renewables.
Natural dyes are limited in colors, but they possess curative properties such as curcumin in turmeric to have antibacterial properties. The most important advantage of natural dye is they show colorfastness which means they are resistant to change their color when comes to contact with other fabrics. Colorfastness allows retaining natural property during external conditions such as washing, rinsing or sunlight.
These dyes are easy to extract i.e. we can get colors by simply boiling plants or flowers, so provide great profits to textile industries. Dyes are obtained by plant pigments and some plants such as indigo and madder contain more pigments than others.
Extracts can be obtained by cutting the desired plant parts such as flowers, stems or leaves. Put them in a container and add water in it then boil for a few hours. Let it cool and stain the liquid, add water to make the desired volume of dye.
Using natural colors makes consumers more attracted to nature as they provide unique hues and softness. It provides aesthetic values and convey natural beauty to customers by delivering contrasting colors that can’t be achieved through synthetic colors. The most popular used natural dyes are: Indigo, Madder, Weld and Cutch and the oldest of them is Indigo. Though natural dyes cause less environmental damage, you also need to consider cost and sustainability that natural dyes don’t meet our all needs.
Uses of natural dyes
- Natural dyes are mostly used for textiles, leather and food substrate purpose.
- These are also used by artists and craftspeople.
- Dyes obtained from plants such as indigo leaves are used in hair dye and in medicated hair oil manufacturing.
- These dyes are also used in the cosmetic industry as they protect from UV radiation and provide anti-aging effects.
- Due to color properties, they are used as pH indicators and in food colorants as well.
Limitations to use natural dyes
Besides, the advantages of natural dyes have some cons. growing natural dye plants, harvest them and then get desired extracts required a large area. To make healthy growth pesticides or herbicides are used which ultimately pose a serious threat to the environment.
When the water from fields run down to nearby stream it causes water pollution. These are limited in color shades and have limitations on the application as well and they are difficult to apply on textiles. Natural dyes are expensive than synthetic as they are obtained naturally.
Color of natural dyes varies crop season to season and uniformity is difficult to achieve which makes it difficult to make a standard recipe for a single color.