The caliper and GSM (grams per square meter) are both measurements used to describe the thickness and weight of paperboard, but they are not the same thing
The caliper and GSM (grams per square meter) are both measurements used to describe the thickness and weight of paperboard, but they are not the same thing.
Caliper, also known as thickness, is a measurement of the thickness of a single sheet of paperboard, typically measured in thousandths of an inch or mils. It is a measure of the distance between the two outer surfaces of the paperboard sheet. Caliper is often used to describe the stiffness and rigidity of paperboard, and is an important factor in determining its suitability for various applications.
GSM, on the other hand, is a measurement of the weight of paperboard per unit area, typically measured in grams per square meter. It is calculated by weighing a standard-sized sheet of paperboard and then dividing that weight by the area of the sheet in square meters. GSM is often used as an indicator of the thickness of the paperboard, as heavier weights generally indicate a thicker paperboard.
In summary, while caliper measures the thickness of a single sheet of paperboard, GSM measures the weight of the paperboard per unit area. Both caliper and GSM are important factors in determining the suitability of paperboard for various applications, but they are distinct measurements that should not be used interchangeably.