Based on the provided reference, the ingredients listed are specifically for the flux component of the solder paste. Solder paste itself typically consists of solder powder mixed with this flux.
The flux in solder paste is crucial for removing oxidation from the surfaces to be soldered and from the solder powder itself, allowing for a strong metallurgical bond. According to the reference, a specific formulation for the soldering paste flux includes the following ingredients:
| Ingredient | Percentage Range | Role in Flux (General) |
|---|---|---|
| Nonylphenol Ethoxylate | 40–70% | Surfactant/wetting agent, aids flow |
| Glyceryl Monostearate | 10–30% | Thickener/rheology modifier, helps maintain paste consistency |
| Acid Activator | 3–10% | Removes oxidation from surfaces and solder powder |
| Water | 3–10% | Solvent, aids consistency and activation |
| Mineral Salt | 4–15% | Can act as an activator or rheology aid depending on type |
These components are blended together to form the flux medium that suspends the solder powder. The exact composition and proportions can vary depending on the specific application, desired properties (like viscosity, printability, and activity level), and the type of solder powder used.
While this reference details the flux composition, it's important to remember that the other primary ingredient in solder paste is solder powder, typically an alloy like tin-lead (Sn-Pb) or lead-free alternatives such as tin-silver-copper (Sn-Ag-Cu). The ratio of solder powder to flux is also a critical factor in the performance of the solder paste.
