Hardness Definition

Indicates the ability of the material to resist the intrusion of external force, that is, the resistance of the material to the indentation of a rigid object. Its size reflects the degree of softness and hardness of the material itself. The Shore hardness is mainly used in adhesives to measure.
Shore hardness, the commonly used grades are shore D/A/00, there are 3 kinds, and the degree of softness and hardness decreases in turn.
Level 00 is generally used on very soft objects such as gels;
A grade is similar to the degree of softness and hardness of rubber with elasticity;
Class D describes hard objects.
The specific hardness is expressed in numbers, and the larger the value at the same level, the harder it is. There is no formula for conversion between levels, generally it can be considered that A90≈D20.