Open Time. ‘Open Time’ is the maximum available time before the substrates must be mated together after applying the adhesive.
Stress cracking in plastics – According to The Fundamentals of Adhesives – Environmental stress cracking (ESC) is defined as the premature embrittlement and subsequent formation of cracks in plastics as a result of both being under stress and in contact with a chemical agent. For more information see https://forgeway.com/environmental-stress-cracking/
Hardness – This rating defines how ‘hard’ the adhesive or sealant is. The more hardness an adhesive has, the less flexible it is.