Solder paste is a mixture of solder spheres held within a specialised form of solder flux. As the name indicates it has the texture of a paste, and hence the name.

The fact that it is a paste means that it can be easily applied to the board during PCB assembly.

The solder particles are a mixture of solder. Traditionally this used to be tin and lead, but with RoHS  legislation has been introduced around the world, to only use lead-free solders. These may be made from a variety of mixtures. One is 99.7% tin and 0.3% copper, whereas there are other mixtures that include other metals including tin.

• Solder paste must be stored under right conditions. For storage, please check here.

• Stir the solder paste slowly before using.

• Adjust solder paste diameter to minimum 20mm’s.

• Add solder paste regularly little by little.

• Set the temperature and humidity.

• Nerver dry solder paste on the stencil.

Between 0-8 °C; 3-6 months. In closed doors that doesnt hit day light in, you can store solder paste for a short time. Please check the expire date before you use.

Temperature:

Affects the viscosity.

Keep it in a proper cold.

Humidity:

Low humidity may dry the solder paste.

High humidity moustrises the solder paste.

Keep it in moderate humidity...