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Safely Handling Dyes

Dyes:

Dyes are one of the tools used by artists in the making of textile art.   They can be defined as a colored substance that has an affinity for a substrate, which in most cases is a textile, to which it is applied.  It is important for the artist to understand the hazards, safe handling, and proper disposal methods of any dyes they may use.

There are many different types of dyes and the type used, depends on the fabric to be dyed.  Dyes may be classified in several ways, according to chemical constitution, application, and end use. The primary classification of dyes is based on the fibers to which they can be applied and the chemical nature of each dye. Factors that artists may consider when selecting a dye include the type of fibers being dyed, desired shade, and the fastness of the dye.

Common examples of dyes that the artist may use include:

  • Acid dyes – These are typically used on acrylics, wool, and cotton blends.  They are sometimes applied in acidic dyebaths.  Most food dyes are considered acid dyes and can be highly toxic.

  • Basic dyes – These are typically used on acrylics, wool, and silk.  Acetic acid may be used in the dye bath.  Fluorescent dyes usually belong to this group.   

  • Direct dyes – These are normally used on cellulosic fibers, silk, and nylon.  The dyebath may include slightly basic solutions.

  • Disperse dyes – These are usually applied to polyester andd water repellant fibers and are therefore typically water insoluble.  The dye is typically applied at high temperatures and acetic acid may be used in the dyebath.

  • Reactive dyes – These are typically used on cellulosic fibers and wool and are typically used in the home or studio.   Reactive dyes form a covalent bond with the fiber and sometimes require the use of high temperature dyebaths during the application process.

  • Vat dyes- These are typically applied to cellulosic fibers and wool.  They typically require the knowledge and use of chemistry and the process can include sodium hydroxide, sodium hydrosulfite, and chemicals necessary for pH control.

  •  Azoic dyes – These are typically used on cellulosic fibers, silks, and acetates.  Azoic dyes require manipulation of the dyebath with various chemicals.

  • Mordant dyes – These typically require the use of a mordant, such as potassium dichromate, to improve the fastness of the dye to the substrate.

It is important for the artist to consider all of the chemicals used in the dying process when disposing the chemicals.  As noted above, the dying process can involve toxics, acids, bases, and oxidizers, some of which may require PPE and will need to be disposed of properly through EH&S through the chemical/hazardous waste pickup form. 
Please refer to our hazardous waste guidelines, the 5Ls, for further guidance.  
If you have specific questions as to how to dispose of your dye materials, please consult your Safety Coordinator or Environmental Health & Safety at x4-8749.