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Table 6-3.—Chemicals Used in Spotting—Continued
Name
Characteristics
Uses
Precautions
Sodium chloride
White, powdered or Helps to remove blood Safe on all fabrics if
Common salt . . .
granular substance
and fruit stains
properly rinsed. Has
setting action on direct
dyes
Sodium
Clear,
colorless,
or Bleach for vegetable and Discolors animal fibers.
hypochlorite . . . .
slightly yellow liquid
synthetic fibers;
to Strong solutions will
remove blood, blue
injure vegetable fibers.
stains, grass stains,
Follow treatment with
indelible pencil, mildew
a sour.
and molds, medicine,
and perspiration stains
Sodium
Whitish, slightly opaque, To remove iodine stains Safe on all fabrics and
thiosulfate. . . . . .
crystalline substance
dyes if rinsed well after
using.
1, 1, 1-Trichloro-
Colorless, nonflammable General spotting agent Safe on all fabrics. If
ethane (Methyl
liquid
for oil and grease stains
warm, may bleed cel-
chloroform) . . . .
lulose acetate dyes.
by oil, solvent may remove the spot or stain. An
indicates the presence of tannin. Wine and berry
ink spot may be tested as follows:
Add a drop of water to the ink spot. If the
ink bleeds easily, it is considered to be water
soluble.
Add a drop of ammonia to the spot. More
color should bleed from the spot.
Add a drop of acetic acid to the spot. If
no more color bleeds, then remove the ink spot
by a water and ammonia process of bleeding and
flushing until spot is completely removed.
If water does not bleed the ink spot, add
dry solvent. If the ink bleeds, then the ink spot
is ball-point, marking, Mimeograph, or printing
ink, which must be removed on the dry side.
Continue bleeding and flushing until spot is
removed.
Chemical tests—Litmus paper indicates the
presence of acid or alkali. Tannin can be
discovered by applying a drop of ammonia to a
spot or stain and noting whether the color turns
tan or brown. The change to tan or brown
stains are distinguished from ink stains by a
discharge of color. The color of wine and berry
stains will change from blue to red and back to
blue with alternate applications of ammonia and
acid.
METHODS USED IN SPOTTING
The spotter removes spots and stains by using
one or more of four following methods:
Solution
Emulsification
Chemical action
Mechanical action
SOLUTION
A solution is a mixture of two substances, the
solvent and the solute. A solution occurs when
the solute is dissolved in the solvent. The most
common way to remove soils and spots from
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