Overview
The YINUO YN-CBY100 Cobb Water Absorbency Tester is a special instrument for measuring the surface Water Absorbency of sizing paper and Cardboard (including Corrugated Board). It adopts the Cobb (Cobb) test method, so it is also called the Cobb absorbency tester or the paper surface absorption weight tester. This instrument is mainly used to measure the surface water absorption (Cobb value) of paper and Cardboard per unit area under certain conditions, but it is not suitable for accurately evaluating their writing performance.
Features
Two standard test area options are available: (100 +/- 0.2) cm ² and (122.718 +/- 0.2) cm ².
2. The key components are made of high-quality materials: the cup body is 316 #stainless steel, and the lid is made of mg aluminum treated by fully enclosed anode hardening.
3. Adopt pure silicone sealing ring to ensure good sealing during the test.
4. The cup lid is designed with 304 #stainless steel swirl/spin, which realizes quick opening and closing of the lid in one second and is easy to operate.
5. The cup body swirl/spin card is made of pure copper, which has good wear resistance performance.
6. Precise roller specifications: length 200 +/- 0.5mm, mass 10 +/- 0.5kg.
Principle
The instrument works based on the principle of the Cobb (Cobb) test method. By placing a specified area of the sample in the mouth of the instrument cup, adding Basis Weight water (test water consumption 100ml +/- 5ml, liquid height 10mm), under the specified pressure and time, the water comes into contact with the sample surface and is absorbed. By measuring the mass difference before and after the sample absorption and substituting the formula C = (G2-G1) × 100 for calculation, the Cobb water absorption value per unit area (g/m2) can be obtained, so that Basis Weight evaluates the Water Absorbency on the surface of paper or Cardboard.
Applications
Determination of Surface Water Absorbency of Adhesive Paper, Cardboard and Corrugated Board
Standards
The instrument is designed to perform Cobb (Cobb) absorbency tests, and its specifications (e.g. test area, press roll mass, etc.) comply with the relevant paper and Cardboard Water Absorbency Test Method standards.
Steps
1. Cut and weigh to obtain the mass (G1) before the sample absorbs water.
2. Place the sample in the specified position of the instrument cup mouth and press the sealing tightly.
3. Add the specified volume (100ml +/- 5ml) of test water to the cup.
4. Start counting, and after reaching the specified test time, quickly pour out the water.
5. Use the pressure roller equipped with the instrument to roll the surface of the sample to remove excess moisture from the surface.
6. Immediately weigh the sample after absorbing water mass (G2).
7. Calculate the Cobb water absorption value (C) according to the formula C = (G2-G1) × 100.
Notice
• This instrument is only used to measure Water Absorbency on Paper and Cardboard and is not suitable for accurately evaluating their writing performance.
• Before the test, make sure that the sample is flat and the cup sealing ring is intact to ensure the accurate sealing of the test area.
• The amount of water and liquid level added should be strictly controlled within the range specified by this instrument (100ml +/- 5ml, liquid height 10mm).
• Before weighing after absorbing water, the matching pressure roller must be used to remove the excess moisture on the surface of the sample according to the specified method, and the operation should be prompt and consistent.
• When calculating the results, pay attention to the conversion of mass units and area units to ensure that the Cobb value (g/m2) is calculated correctly.
• The instrument should be cleaned and dried in time after use, especially the metal parts and sealing rings, to maintain its accuracy and life.
