Otto's Original - Quality products since 1901


No clean, alcohol and water based flux, di-carboxylic acids,
resin free, halogen-free (WEEE/RoHS conformant)
Type 2131 // ORL0 acc. ISO 9454 // DIN EN 61 190-1-1

Packaging units:
20 l
Application area: Wave- and selective soldering, manual- and repair soldering, dip soldering
Appearance/smell: colorless, clear
Solids content: 3.5 Gew.-% (wt.-%)
Density at 20 °C: 0.87 (+/- 0.01) g/ml
Acid number: 28–32 mg KOH/g
Activators: di-carboxylic acids
Solvents: short-chain alcohols and water
Flash point: 12 °C
Durability: 24 months
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The SD-35 is a halogen-free soldering flux with a reduced alcohol component. It has been developed for selective and wave soldering processes. It has a solids content of 3.5% and is characterized by excellent soldering properties. The chosen combination of alcohol and water
makes it possible to make optimum use of the advantages of both solvents. The evaporation behaviour of SD-35 is considerably better than with water-based fluxes. Therefore it is also suitable for manual and dip soldering and thereby fulfills all the requirements of a multiflux.

Practice has shown, that with the correct application, no washing of assembled printed circuit boards soldered with this flux is needed.

The surfaces of the soldered printed circuit boards are very clean after the soldering process.

Customer added value:

  • Wide range of applications (multiflux)
  • Very good soldering properties (capillarity, wetting)
  • Broad process window (high thermal stability, good activity over a long interval)
  • Very good residue behaviour (optically very clean, high SIR)

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