stain and stain removal - A stain is a substance which can color a porous or absorbent material, usually in a translucent manner; or the act of such a coloring; or the result of such a coloring.

Various colors for staining wood, cement, and other materials are commercially available.

"Stain" is also frequently used to describe an unintended discoloration; a blot.

Following is a chart of directions for the removal of stains of this latter type from fabrics. (An art conservator might use more sophisticated methods than these, frankly.)

How to Remove Stains from Fabrics

Stain	On washable fabrics	On dry-clean fabrics
Acrylic paints	Remove with water while still wet.	Sponge with water; then dry-clean.
Ball-point pen	Soak in solution of detergent and warm water. Rinse in cold water. Wash normally. If fabric can be bleached, use mild bleach.	At your dry-cleaner's shop, specify that the stain was made by a ball-point pen.
Berry and other fruit	Launder. If stain remains, apply white vinegar; rinse.	Apply white vinegar; rinse.
Blood	Soak in cold water. Launder. If fabric is white, use bleach.	Sponge with cold water and salt (one tablespoon per quart of water). Rinse and blot with a towel.
Candle wax	Rub wax with an icecube until hard; then scrape off with a blunt knife. Or, place paper towels under and over the wax, and press with a warm iron.	Same method as on washable fabrics.
Chewing gum	Rub wax with an icecube; then scrape off with a blunt knife.	Same method as on washable fabrics.
Cosmetics	Pretreat by rubbing detergent dissolved in mildly water into the spot. Launder.	Use a greasy stain solvent; dry-clean.
Grass	Work detergent into the stain; then rinse and launder. If fabric can be bleached, use bleach in the laundry.	Same method as on washable fabrics.
Grease	Sprinkle liberally with talcum powder or cornstarch. Let the powder absorb the grease, then brush the powder off.	Same method as on washable fabrics.
Ink	Pour water through the stain until it runs clear. Then apply detergent and white vinegar; rinse.	Same method as on washable fabrics.
Nail polish	Sponge with alcohol mixed with a few drops of ammonia. Use nail polish remover only after testing it on an inconspicuous portion of the same fabric.	Same method as on washable fabrics.
Oil paints	Sponge immediately with turpentine. Then rub detergent into the stain and launder.	Same method as on washable fabrics.
Pencil (graphite)	Erase with a soft eraser. Work detergent into the remaining stain; rinse and launder.	Erase with a soft eraser, then dry-clean.
Perspiration	If the fabric's color has been affected, sponge a fresh stain with ammonia, an old stain with white vinegar. Rinse and launder. If color has not been affected, rub with detergent and launder.	Same method as on washable fabrics.
Scorch	Sponge with hydrogen peroxide or ammonia. Rinse well and launder.	Dampen with hydrogen peroxide until stain is removed.
Tempera paints	Remove with water. Then rub detergent into the stain and launder.	Sponge with water, then dry-clean.
Varnish	Sponge immediately with turpentine. Then rub detergent into the stain and launder.	Same method as on washable fabrics.
Watercolor paints	Remove with water. Then rub detergent into the stain and launder.	Sponge with water, then dry-clean.

Examples of art using stains:

Morris Louis (American, 1912-1962), VAV, 1960, acrylic on unprimed canvas, 260.3 x 359.4 cm, Tate Gallery, London. These Color Field paintings were made by staining canvas rather than painting on it.

Morris Louis, Alpha-Phi, 1961, acrylic on unprimed canvas, 259.1 x 459.7 cm, Tate Gallery, London.

Samples of manufactured wood stains which are commercially available, given the names: Natural, Golden Oak, Provincial, Red Oak, Puritan Pine, Ipswich Pine, Colonial Maple, Special Walnut, Red Mahogany, Early American, Fruitwood, Golden Pecan, Pickled Oak, Driftwood, Dark Walnut, Ebony, and Jacobean.

Also see art conservation, bleed, cleaning, cleaning art, dye, eyedropper, foxing, pigment, solvent, wash, water-soluble, and wood.

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