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Bleaches with perborate and percarbonate
Comparison between normal and activated bleaches
Remission [%] = Bleaching action
30
25
20
15
10
5
0
HO
HO
O O
B B
O O
Tea, coffee, ...
Activation
OH
OH
2 –
2 Na +
Activation systems for laundry detergents
or Na 2CO 3 • 1.5 H 2O 2
H 2O
H 2O 2 + OH – HOO – + H 2O
0 20 40 60 80
Bleaching activation
Persalt
Percarbonate
or perborate
R
X
O
Temperature [°C]
Oxidized stain
Example: TAED activation
Persalt
OOH –
H 2O / OH –
TAED
Peracetic acid
H 2O 2 + OH – HOO – + H 2O
Activators
• TAED, NOBS
• Ester, amide
• Nitril(quat)
H
O
Washing solution
Catalysts
• Enzyme/mediator
• Metal complex
• O carrier
In-situ peracid (X=O, NH) Bleaches
Activated species
O
M
Modern all-purpose laundry detergent—
clean, pure and fragrant
All-purpose laundry detergent is always “a child
of its time.” Laundry habits, consumer behavior,
re gulations and environmental protection have
always influenced the development of new and advanced
ingredients and formulations. But the principles
of wash performance have never chang ed:
mechanical forces, thermal energy and chemical
reactions do a really good job against dirt and
body oils on laundry. And for over 100 years, the
role of bleach in that success has remained unchanged.
Perfumes, the final ingredients in the
mix, reinforce the impression of cleanness.
“Self-acting” laundry detergents were a hit
from the start, and as purchasing power increased
and drum-type washing machines became available
during the years of the German Economic
Miracle, almost all classes of Germans could now
afford them. But with the steady rise in laundry
detergent sales came a gradual increase in environmental
pollution. The use of phosphate-based
softening systems in laundry detergents caused
eutrophication, an unwanted increase in the chemical
nutrients of bodies of water that generates
excessive plant growth. In the 1980s, this phenomenon
led to increased environmental awareness
and, ultimately, a ban on phosphate-based laundry
detergents in Europe. Today’s laundry detergents
contain either zeolites, polyacrylates or softener
systems based on sustainable raw materials (for
example, citrates, aspartates) to prevent formation
of lime soaps.
The interaction between mechanical energy
(the rotation of the machine’s drum), the temperature
in the washing solution, and the chemical
action of the surfactants control the actual process
for removing dirt and body oils. Surfactants also
hold the dirt and fat particles suspended in the
wash water. The less water today’s water-saving
washing machines use, the more dispersants the
laundry detergent has to provide to prevent the
dirt particles in the concentrated solutions from
settling back on the fibers and turning the laundry
grey.
In their fight against a variety of different
stains, surfactants receive help from enzymes and
bleaches. Enzymes are proteins that convert only
certain organic substances by catalytic action, and
can split into smaller components. Proteases, for
example, are used to fight protein stains, lipases
take on grease, and carbohydrases battle starchy
soiling.
Because an increasing number of foods are
pro duced with non-digestible polysaccharides
(for example, low-calorie products), more expen-
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