Dye Chemistry


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Dyes in Culture
Click here to learn about dye use in cultures- henna, batik, achiote and Navajo dyes

Natural Dyes in Culture include:

Indigo - Indigofera tinctoria - blue (Fabaceae)
Saffron - Crocus sativus - from red stigmas
Confederate gray - Juglans cinerea (butternuts)
Woad Blue - Isatis tinctoria (Brassicaceae)
Bloodroot - Sanguinaria canadensis (Papaveraceae)

Dye Terms in Common Language
Origins of terms such as "dyed in the wool" and "red tape"

Dyes in Life Worsheet
Complete this worksheet at home

Dye Chemistry Categories

Natural Dyes

For thousands of years, dyes were obtained from natural surces, such as plants and animals. In spite of the fact that synthetic dyes have replaced many natural dyes for commercial use, natural dyes still hold a fascination and are used extensively by artisans around the world. The most common type of natural dyes are acid or anionic dyes used on eggshells and wool.

 

Vat Dyes

Indigo and Inkodyes are used to illustrate how vat dyes are synthesized and used. Until the end of the 19th century, all colors were obtained from natural sources, but today the number of synthetic colorants exceeds 7,000. One class of these colorants, the vat dyes, contains not only the oldest natural dyes known, but also many important synthetic dyes.

Synthetic dyes from coal tar (aniline) produce a wide array of colors and are more colorfast.

Food Dyes

Dyes aren't just for fabrics. Colrants have been added to food for centuries to enhance its appearance. Synthetic colorants are currently approved for use in foods. Color is a big factor in what foods we choose and how much we enjoy a food. Many food dyes have been banned through the years because they were shown to cause cancer. Currently only 7 FD&C dyes are approved in the US. While some food colorings are natural, 95% of those used today are artificial.

History of Natural & Vegetable Dyes

Dyes

A Natural Dye Activity

Kathryn of the Hills Dye Book

Deepak Chemicals

Vat Powders

Royce Textile Division

 

TR-383

Food Dyes

 

 

FDA:Color Additives

 

Read more about the food dye controversy here.


 

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Draw your own Dye Chemical

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Chemistry of bonding of dyes to fibers is complex, involves direct bonding, H-bonds, hydrophobic interactions.

Mordants - increase binding of dye to fabric by forming a chemical bridge from dye to fiber, can also affect color.

 


Search for Dye Chemicals



ChemFinder Search

Enter a chemical name, CAS Number, molecular formula, or molecular weight

from www.chemfinder.com

 

Computer Modeling of Chemical Compounds

 

click here to see an example

ISIS Draw - 2D Chemical structure drawing program free to download. For Mac and Windows.

Chemsketch - 2D Chemical structure drawing program for Windows only. Free.

 

MolMol - 3D molecular modeling for Windows 95 only. Free to download.

MacMolecule for Mac - for viewing 3D images. Free to download.

Chime - Browser plug-in to enable you to view 3D models on the web. Free to download.

Dye Chemistry Lab Resources   

Using Kool-Aid

 

 

How To Dye Cloth

In search of Yellow Dye #5



Information for this unit from:

Palette of Color Monograph Series by Dianne N. Epp
Terrific Science Press
Miami University Middleton
Available from
NSTA Books

Dye Chemistry Quiz-check your answers