Name: Debra M.
What makes ink stains difficult to remove with regular
What happens between the ink and fabric? My daughter has asked this
Question- a project for school- we have tested many liquids and are able
to remove many with stain removers, but ink is one of the darker stains
Stains can (sometimes) be removed by application of one or more of about
1. Sometimes the colored (stain) molecules can simply be dissolved in and
suspended within micelles of water and soap or detergent (... you can look up
the definition of a micelle in a dictionary or science encyclopedia on the
net) and then rinsed away with lots of clean water. This is the traditional
washing machine approach.
2. Sometimes the stain molecules can be cut (oxidized) into smaller
molecular fragments that are less colorful or even colorless by the action of
a bleach or enzyme in the laundry product. This often happens when
enzyme-fortified laundry products go to work on grass stains and blood. Then
the process described above can be used to remove the residues.
3. Some stains cannot be dissolved and suspended in water even when
fortified with soap or detergent. However, they might be soluble (and thereby
removable) by the effects of cleaning fluid solvents such as those used by
Inks sometimes contain oxidation-resistant and/or particulate colored
substances that bind tenaciously to fabrics and can be difficult to nearly
impossible to remove. For example: The ink in laundry marking pens and the
stuff referred to as "India ink" are suspensions of carbon black (sorta like
soot) in a liquid. Once applied to the fabric, the carbon black soaks into
the pores of the fabric where it tightly binds to the fibers. Since the
carbon black is not attacked by enzymes, is resistant to oxidative attack by
bleach, and is not emulsifiable by soap and water, it is all but permanent.
Thus the term, "permanent marker." Some artists' inks contain colored
particulates. These inks can be distinguished from simple dye solutions
because they are not clear. Rather, they look a little cloudy.
I hope this is of assistance.
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Update: June 2012