Definition - What does Transfer Efficiency mean?
Transfer efficiency is the amount of coating solids that successfully adhere to the base material to which they are targeted versus the total amount of coating solids that are used during the spraying process. A lower transfer efficiency means that the coating application process is more wasteful than a coating application process with a higher transfer efficiency.
Corrosionpedia explains Transfer Efficiency
Transfer efficiency is a significant metric when selecting a coating application process. The transfer efficiency of a coating application informs the end user of how much coating material they will successfully use during the coating operation and how much they will waste. For example, if a coating application process has a transfer efficiency of 75%, and it is known that 30 pounds of coating material will need to be applied evenly over a substrate, then the user can deduce that they will need at least 40 pounds of coating material to get the job done. They also know from the transfer efficiency metric that they will be wasting at least ten pounds of coating material.
When selecting a coating application method, it is important to weigh the costs of selecting a lower transfer efficiency process. If the coating material is a major portion of the total cost then it may make sense to opt for a more expensive coating process but with a higher transfer efficiency. While the fixed cost of the coating equipment may be higher, the variable cost of the coating material being lower could negate this.
Another consideration is the environment. Wasted coating has to go somewhere, and if it not properly collected it could be released into the environment where it could cause environmental damage.