Calculating the amount of water absorbed by the surface of the paper, board or corrugated sheet is known as the water absorbency of that material. There are various test methods and related instruments present for evaluating the absorbency strength of the material. One of the renowned testing instrument among all others which is commonly used for calculating the water abortiveness is Cobb sizing tester.
By conducting the Cobb sizing test, water absorbent rate of papers, boards, and related products can be easily evaluated.
The Cobb test
A Cobb test is a highly effective test method which is utilized to compute the water absorption rate and the sizing acceptability of the materials.
In the test, first, we fill the cylindrical ring structure with water and expose the sample’s upper side to water. After a particular time period, the water will be drained, and the extra water will be blotted off from the sample’s surface using a roller which comes with the machine. The water can be blotted off by rolling over on the specimen in forward and backward direction without putting any sort of pressure on the roller. After extracting the extra absorbed water, the paper sample is weighed. The amount of weight obtained by the paper sample post soaking in water is considered as its water absorbency.
By performing this test, we can calculate the amount of water absorbed by a specimen or the resistance it has in a particular time period so that it can be ensured that the product will behave in the same way in real life moisture conditions. The absorbency is measured in unit g/m2. It is also an important factor which influences the printability of water-based adhesives. Cobb sizing tester presented by Labtiger is an efficient instrument which is popularly used by many industries for performing the Cobb test and evaluate the water absorptiveness of a particular specimen. It is used for a various form of a product such as paper, cardboard and corrugated sheets. It complies with the testing standards of IS 1060 and TAPPI –T441.
The important features delivered with the machine are as follows:
- The machine has a strong rugged structure with corrosion resistant main body
- It is light weighted and resilient for providing more user comfort.
- Rapid locking mechanism offered with the machine.
- The single handed operation to ensure hassle-free
- Use of high-grade stainless steel in building the test area.
- Ensure highly accurate test results