Overview
COB100 Cobb value tester is a special instrument designed according to the basic parameters and requirements specified in GB/T1540-1989 Paper and Cardboard Water Absorbency Determination Method (Cobb Method). The instrument is suitable for measuring Water Absorbency on various paper or Cardboard surfaces, and is a conventional equipment for Water Absorbency testing on paper and Cardboard surfaces.
Features
1. High test area accuracy: (100 +/- 0.2) cm ² and (122.718 +/- 0.2) cm ² dual specifications
2. Pressing roller mass accuracy: standard pressing roller weight 10kg +/- 0.5kg, can be customized according to requirements
3. Excellent sampling accuracy: sampling diameter 125mm, sampling size error +/- 0.2mm, sampling thickness range 0.1~ 1.5mm
4. Advanced blade technology: special treatment die blade, 10,000 wire high-precision wire cutting, triple high temperature quenching, triple fine grinding
5. Precision positioning structure: three-point positioning method, High Accuracy coaxial concentric process, three-point guide rail positioning structure, pure copper wear-resistant copper sleeve
Principle
The instrument is based on the Cobb (Cobb) test method to determine the water absorption (Cobb) value on the surface of paper and Cardboard, that is, the water absorbed by the surface of paper and Cardboard per unit area within a specified time under a certain pressure and temperature, in g/m2. The calculation formula is: C = (G2-G1) × 100, where C is the water absorption value of Cobb, G2 is the sample mass after water absorption, and G1 is the sample mass before water absorption.
Applications
Determination of Water Absorbency on Various Paper or Cardboard Surfaces
Standards
Paper and Cardboard Determination of Water Absorbency (Cobb Method)
Steps
1. Preparation of samples: using instrument sampling, sample diameter 125mm
2. Weighing pre-treatment: weighing the sample mass G1 before water absorption
3. Conduct water absorption test: add 100ml +/- 5ml of water to the test area and maintain the specified time
4. Weighing post-treatment: Weigh the sample mass G2 after absorbing water
5. Calculation result: Calculate the water absorption value of Cobb according to the formula C = (G2-G1) × 100
Notice
• This instrument is not suitable for accurately evaluating the writing performance of paper or Cardboard
• Test environmental conditions should be controlled at temperature 20~ 40 ℃, relative humidity < 85%
• Ensure that the weight of the roller meets the standard requirements before use
• Pay attention to control the thickness in the range of 0.1~ 1.5mm when sampling
• Regularly check blade abrasion to ensure sampling accuracy
