Protection upgraded
SurTec® 181
Aluminium Etching
Properties
highly alkaline liquid
free of phosphates and silicates
free of surfactants
Application
SurTec 181 is usable for soak- and spray applications for etching and degreasing with etching
attack on aluminium. Therefore SurTec 181 can be combined with soak or spray surfactants of
the SurTec-Range (e.g. SurTec 089 or SurTec 086, respectively). The make-up should be
preferably prepared in deionised water.
make-up value: SurTec 181 2-7 %vol (corresponds 3-10 weight%)
+ surfactant 0.05-0.5 % (if necessary)
aluminium content: 0-50 g/l
temperature: 40-90°C
application time: 0.5-10 min
tank material: stainless steel, or alkali-resistant material
heating: required, out of stainless steel or alkali resistant material
Technical Specification
(at 20°C) Appearance Density (g/ml) pH-value (at 10 g/l)
SurTec 181 liquid, colourless-yellow 1.452 (1.42-1.49) 12.5 (12-13)
Maintenance and Analysis
Analyse and adjust the concentration of SurTec 181 and of aluminium.
Sample Preparation
Take a sample at a homogeneously mixed position and let it cool down to room temperature.
If the sample is turbid, let the turbidity settle down and decant or filter the solution.
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SurTec 181 – Analysis by Titration
reagents: 1 N hydrochloric acid or sulfuric acid
sodium fluoride (NaF) - solid
indicator: phenolphthalein (0.1 % in ethanol)
procedure: First titration:
1. Pipette 20 ml bath sample into a 250 ml Erlenmeyer flask.
2. Dilute to approx. 100 ml with deionised water.
3. Add 3 drops of indicator.
4. Titrate with 1 N acid from red to colourless.
acid consumption in ml = X (ml)
Second titration:
5. After the first titration add approx. 2.5 g solid sodium fluoride
and mix thoroughly (the solution becomes red again).
6. Titrate again with 1 N acid until the solution is colourless.
acid consumption in ml = Y (ml)
calculation: 0.429 · (X - Y/3) = %vol active content of SurTec 181
Y in ml · 0.45 = g/l aluminium
If the bath is freshly prepared, only the first titration is necessary.
The calculation therefore is:
X in ml · 0.429 = %vol SurTec 181
Ingredients
polyalcohols
sodium hydroxide
Consumption and Stock Keeping
The consumption depends heavily on the drag-out. To determine the exact amounts of drag-out,
see SurTec Technical Letter 11.
In order to prevent delays in the production process, per 1,000 l bath the following amount
should be kept in stock:
SurTec 181 50 kg
Product Safety and Ecology
Classification and designation are noted in the Material Safety Data Sheets (according to the
European legislation). The safety instructions and the instructions for environmental protection
have to be followed in order to avoid hazards for people and environment. Please pay attention
to the explicit details in our Material Safety Data Sheets.
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Warranty
We are responsible for our products in the context of the valid legal regulations. The warranty
exclusively accesses for the delivered state of a product. Warranties and claims for damages
after the subsequent treatment of our products do not exist. For details please consider our
general terms and conditions.
Further Information and Contact
If you have any questions concerning the process, please contact your local technical
department.
For further information and contact details please visit our homepage:
http://www.SurTec.com
26 February 2015/DK, PV
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