While the provided reference does not specify an exact temperature at which solder mask burns, it does provide crucial information about the high temperatures these materials are engineered to withstand during standard electronics manufacturing processes.
Solder mask is a critical protective layer on printed circuit boards (PCBs). Its main role is to prevent solder from bridging traces during the soldering process, ensuring connections are only made where intended.
Solder Mask High-Temperature Resistance
During soldering, especially in processes like wave soldering, the PCB and its solder mask are exposed to the very high temperatures of molten solder. Solder mask formulations are specifically designed to survive this brief but intense thermal exposure without degrading.
According to the provided reference:
Solder mask is engineered to withstand molten solder temperature for the very brief time (about a second) it is exposed in a typical wave soldering process. Most commercially available masks should be able to withstand melting point temperatures of lead-based and lead-free solder, up to 650°F (343°C).
This indicates that commercially available solder masks are formulated to maintain their integrity when momentarily exposed to temperatures up to 650°F (343°C), corresponding to the temperatures of molten solder.
Key Temperature Point
| Temperature (°F) | Temperature (°C) | Condition Withstood | Exposure Time |
|---|---|---|---|
| Up to 650°F | Up to 343°C | Molten Solder Temperature | Brief (~1 sec) |
This temperature represents the material's ability to withstand the heat for a very short duration, not a continuous operating limit or a burning point under prolonged exposure.
Practical Considerations
- Exposure Time: The ability to withstand 650°F (343°C) is specifically for the brief exposure typical in wave soldering (around one second). Prolonged exposure, even at lower temperatures, could potentially cause degradation or damage.
- Material Variation: Different types of solder mask (e.g., liquid photoimageable, dry film) and specific formulations from various manufacturers may have slightly different thermal characteristics.
- Damage vs. Burning: While the reference doesn't define a "burning" temperature, exceeding the material's thermal limits for too long or at much higher temperatures could lead to visible damage such as discoloration, blistering, delamination, or charring, which could be considered burning in a practical sense.
In summary, based on the provided reference, solder mask is designed to withstand temperatures up to 650°F (343°C) for a brief period during soldering processes. This is the temperature range associated with its survival of molten solder contact, rather than a specific continuous burning point.
