Otto's Original - Quality products since 1901
Solar products


No Clean-Flux especially for the solar industry, halogen-free
ISO-9454: 2231 (2.2.3.A) / WEEE /RoHS-compliant
DIN-EN 61190-1-1 (acc. J-STD-004B): (IEC ORL0)

Packaging units:
Canister 5 and 20 litres
other packing sizes on request
Application area: Soldering of solar modules, tabber- and stringer material, as well as the connecting of cells
Appearance/smell: colourless, transparent, liquid
Solids content: 2.0 Gew.-% (wt.-%)
Density at 20 °C: 0.9 – 1.0 g/ml
Acid number: 15 - 19 mg KOH/g
Activators: di-carboxylic acids, synth. resin
Solvents: Water with added alcohol
Flash point: not applicable °C
Additive: wetting agents, alcohol compound <15%
VOC: 15 %
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This flux has been specially developed for solar technology, in particular for soldering solar modules, tabber- and stringer-material, as well as connecting cells. EO-S-012 is a No Clean-Flux, halogen-free formulated and optimized for use in wave, selective and manual soldering processes. It is based on organic, rosin free, activating additives in a combination specially tuned to the thermal requirements of the wave-soldering process with lead and lead-free solders. EO-S-012 contains small amounts of special alcoholic additives for stabilization and improved drying times compared to conventional water-based fluxes. The Flux was mainly developed for low-melting processes (Bi-solders).
EO-S-012 leaves no sticky residue. The activators are specially designed for the higher temperatures that are required in the manufacture of solar modules, without affecting their effectiveness. The application can be carried out by any usual application method (except foams).
The solids content is 2 %.
EO-S-012 is totally free from corrosion action.

Safety instructions: Please refer to the current MSDS

Instructions for use:
This flux is very versatile and OPS-compatible. There are good results for manual, wave and selective soldering, as well as for cable assembly / wire tinning. The general rule of applying fluxes applied in principle as low as possible also applies to this product.

Sprayfluxing: If possible, try at first a quantity of 30 – 50 ml/min. and observe the distribution of the flux. After that, correct the quantity. Air-pressure: 18 – 20 l/min.

Preheating: Entering the solder-wave, the temperature on the topside of the pasteboards should be 80 – 110 °C, dependent on type of boards, lay-out etc. – in case of using lead-free solders, preheating temperatures of 100 – 125 °C on the topsides are possible.


Questions about our products?
We will advise you by phone 06123 / 7046-0.