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Name: Diane B.
Status: other
Age: 40s
Location: N/A
Country: N/A
Date: 9/22/2003

Why are grass stains so hard to get out of fabrics?


Grass stains are more than just the green material (chlorophyll) in the plant's juices. Other relatively stable pigmented compounds (xanthophylls, carotenoids, etc.) may also be present. Such materials may bind tightly to natural fibers such as cotton, silk, and wool because the molecular structures of the staining material and fabric fibrils may be chemically compatible. In other words, the stain may penetrate the fabric fibrils and form a bond therein. Penetration is very different that simply sitting atop the fibril -- such as might be the case with a stained synthetic fabric like polyester or nylon etc. In this case the stain and fabric chemistry are rather incompatible thus the term, "stain resistant." Sometimes fabrics can be treated with materials like ScotchGardT to make the outer surfaces of the fabric's fibrils stain incompatible.

Stain components may be lifted with suitable detergents. However, some stains respond to enzymatic attack. The approach one takes to stain removal is to discover which kind of cleaning agent works best.

ProfHoff 725

Hi Diane!

Trees and grass (and all plants) are green because they have a green dye (called chlorophyll) used to produce sugar. In fact, when we "get a "grass stain", it is actually a "chlorophyll stain," says Art Cameron, horticulturist at Michigan State University.

During summer, tree leaves and grass absorb light energy and, through a series of reactions, convert that energy to a more stable form that is, carbohydrates. The conversion process is called photosynthesis. Since chlorophill is a dye, a pigment, it stains.

If you want to get rid of the stain, leave the fabric soaked in water for many hours. If it still dont go away there are special commercial products for cleaning.

Thanks for asking NEWTON!

(Dr.) Mabel Rodrigues

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