Gurley Cobb Size Tester (Standard Type) - OpTest

The test consists in measuring the water absorptiveness of a single side of paper or paperboard when exposed to water for a specified duration. By calculating the mass increase, the tester determines the sizing degree of the material, which indicates its liquid penetration resistance.

The specimen is placed on a metallic plate on the rubber mat. On the top of the specimen of a certain area, a metallic ring is placed and fixed. Pour water up to the level of 10mm in the ring so that the water is gradually absorbed by the specimen. The difference in weight before and after wetting (absorption amount) is read to 0.01g as absorption degree.