Water Resistance
Definition
Ability to resist moisture ingress and maintain bonding performance.
Historical Background
1970s: waterproof PSAs achieved underwater bonding.
Example
Ordinary tape on bathroom mirrors falls off. Waterproof tape uses special formulation.
Formula
Water Resistance Duration = f(Adhesive Thickness, Crosslinking, Hydrophobicity)
Core Concepts
Balance between hydrophobicity and cohesive strength.
Extended Applications
Indoor: humidity; outdoor: rain; underwater: submersion; medical: perspiration; marine: seawater.