Difference between Synthetic Dyes and Natural Dyes

Post on 18-Aug-2015

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Transcript of Difference between Synthetic Dyes and Natural Dyes

Difference between Synthetic Dyes and Natural Dyes

Hafeezullah MemonZSTU, Hangzhou, China

What is Dye

• A natural or synthetic substance used to add a color to or change the color of something.

• "blonde hair dye"• synonyms: colorant, coloring

agent, coloring, color, dyestuff, pigment or tint.

Natural Dyes

• Natural dyes are dyes or colorants derived from plants, invertebrates, or minerals. The majority of natural dyes are vegetable dyes from plant sources.

• a great source for natural dyes can be found right in your own back yard! Roots, nuts and flowers are just a few common natural ways to get Natural dyes.

Synthetic Dyes

• A Synthetic dye is any of the organic dyes originally derived from coal-tar derivatives, but currently synthesized from benzene and its derivatives.

• The first human-made organic dye, mauveine, was discovered serendipitously by William Henry Perkin in 1856.

How to Make Natural Dyes

12 steps

Step 1

•Collect your plant materials when they are at their peak of color. Flowers should be fresh, Berries should be very ripe, not withered.

Step 2

•Chop all plant materials into small pieces (inch or smaller) and place them into a large pot or pan that you are willing to sacrifice to the cloth dyeing craft. You will not be able to use it for cooking again.

Step 3

• Measure the amount of plant material and place twice as much water as plant material into the pot with the plant material

Step 4

• Bring the mixture to a boil and then simmer it, stirring occasionally, for at least an hour.

Step 5

• Strain out the plant material and set the dye bath aside.

Step 6

• Place your fabric into a color fixative bath such as salt water (1 part salt to 16 parts water) or a vinegar bath (1 part vinegar to 4 parts water).

Step 7

• Allow the fabric to absorb the color fixative mix and simmer it for an hour

Step 8

• Remove the fabric from the fixative and wring it out thoroughly.

Step 9

• Place the wet fabric into the dye mixture and simmer it until the desired color is achieved. The dry product will be lighter than the wet product, so go for a slightly darker color when wet.

Step 10

• Remove the fabric from the dye bath with rubber gloves. (You want to dye the cloth, not your hands.)

Step 11

• Wring the fabric thoroughly and hang it up to dry

Step 12

• Launder naturally dyed fabrics in cold water and separate from other laundry.

Natural dyes can be extracted from following animals and plants for the following colors.

Animal:• Cochineal insect

(red)• Cow urine (Indian

yellow)• Lac insect (red,

violet)• Murex snail

(purple)• Octopus/Cuttlefish

(sepia brown)

Plant:• Catechu or Cutch tree (brown)• Gamboge tree resin (dark mustard

yellow)• Himalayan rubhada root (yellow)• Indigofera plant (blue)• Kamala tree (red)• Madder root (red, pink, orange)• Myrabolan fruit (yellow, green, black)• Pomegranate peel (yellow)• Weld herb (yellow)

How to Make Synthetic Dyes

These dyes are made in industry through chemical reactions, such as chromatography. Every Dye has different chemistry and their chemistry can be studied and analyzed.

Differences between Both dyes

• With exposure to light all color fades, but natural dyes fade or mellow leaving lighter tones that are just as beautiful, if not more so, than the original color.

• Natural dyes are more compatible and harmonious with one another. By contrast, chemical colors are easy to use and can produce good results, but have certain drawbacks, in that they can look hard or garish; some fade very quickly, and others fade unevenly leaving blotches.

• One of the key reasons why natural colors look better than chemical colors because they are not 'pure' color: a natural red, for example, will include blue and yellow, whereas a chemical red will only contain red pigment. The impurities of natural dyes, which may comprise from five to 25 percent of the dye, consist of other hues that are similar to the main one, and it is these mixtures that make natural dyes so beautiful and create their harmony with neighboring natural colors. Where one person will see some purple in a hank of gray yarn, another may see some blue in it.

Differences between Both dyes (Cont.)

Differences between Both dyes (Cont.)

• Natural dyes make different shades at the different time of the day. When these natural dyes expose to the light, they leave lighter tones, which makes them to look beautiful in different way than their original colors.

• Natural-dye enthusiasts see "mellow" hues that sparkle and glow which give esthetically comfortable feeling. But to be able to see these features one needs, perhaps, a passion for color.

Differences between Both dyes (Cont.)• Natural dyes are substantially less destructive to the

environment than the chemical dyes widely in use. Synthetic dyes used in textile dyeing generally cause environmental pollution and health problems in humans.

• Each plant provides an amazing diversity of shades. From one plant one may obtain between 5-15 varying colors and shades. These colors and shades are subtle and tend to harmonize with one another. The resulting fabrics or fibers are now original pieces - it is extremely difficult for anyone to duplicate exactly (even the dyer)

Differences between Both dyes (Cont.)

• Natural color is inherently more muted than chemical color, which looks very stark, and so if chemical colors are used while the desired effect is for the 'natural' look, it will be necessary to mix a variety of colors in imitation of nature.

• Color created from natural elements lasts much longer than chemical dyes.

Showing these all aspects, can we say that Natural Dyes are better..

Certainly not. . .

But!!!!

Both have their own advantages and disadvantages.

There are three more aspects for choosing Natural or Synthetic Dye

Intensity and Brilliance

• Natural dye color variation and brilliance is achieved by mixing different mordants with one batch of skeins, manipulating the pH of the dye baths, investing hours of time for one color. Colors obtained from natural sources tend to be earthy and subtle. Synthetic dyes often produce garish, stark or muddy colors. Wool rugs prepared with natural dyes are colorfast and will last a lifetime. Colorfastness can be tested by rubbing the surface of the weaving (if the weaver lets you) with a damp cloth. If the dye does not transfer, there is a good chance that the color is permanent.

The Price Difference

• Natural dye materials are scarce and expensive. For example, cochineal is more costly per ounce than gold. Synthetic dyes are readily available at low cost, resulting in a less costly rug to produce. Density of weave also adds to quality and therefore to cost. A low cost rug will likely be woven with synthetic dyes, on brittle, machine spun (not hand-spun) wool, and have a looser weave.

Health and Wellness

• The chemical fumes that are breathed in from the vapors of the dye pot are toxic. Sulfuric acid is potent and can burn the skin. If it splashes into the eye a person can go blind. Because people dye at home and there are not regulations around the use of chemical dyes, most people don’t take necessary precautions to use a face mask. As a result, over time many develop respiratory problems and lung cancer. A movement toward the use of natural dyes is also a good public health step. If you buy a rug dyed with natural materials, even though it may be more expensive, you know you are making a difference for a healthier life.

Thanks. . .