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Name: Debra M.
Status: other
Age: 30s
Location: N/A
Country: N/A
Date: 2000


Question:
What makes ink stains difficult to remove with regular stain removers?

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 that persist.Why?


Replies:
Debra,

Stains can (sometimes) be removed by application of one or more of about three approaches.

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 dry-cleaners.

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.

Regards,
ProfHoff



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