IDM C0005 Cobb Absorption Tester
| Brand | IDM |
|---|---|
| Origin | Shandong, China |
| Model | C0005 |
| Test Area | 100 cm² (2500 px²) |
| Standard Compliance | ISO 535, TAPPI T 441, AS 1301.411s |
| Dimensions (H×W×D) | 240 × 120 × 200 mm |
| Net Weight | 3 kg |
| Roller Stand Weight | 11 kg |
| Operating Principle | Gravimetric water absorption measurement after defined contact time (Cobb method) |
Overview
The IDM C0005 Cobb Absorption Tester is a precision-engineered gravimetric instrument designed for the standardized determination of surface water absorption capacity in paper and board materials. It implements the internationally recognized Cobb test method—defined by ISO 535, TAPPI T 441, and AS 1301.411s—to quantify the mass of water absorbed per unit area (g/m²) following a fixed immersion duration (typically 60 or 120 seconds). The instrument operates on a fundamental principle: a conditioned, pre-weighed specimen is clamped under controlled pressure between a stainless steel ring and a rubber-faced steel plate; distilled or deionized water is introduced into the annular reservoir formed by the ring; after the prescribed contact time, excess water is drained and the wet specimen is immediately re-weighed. The difference in mass, normalized to the exposed test area (100 cm²), yields the Cobb value—a critical parameter for evaluating sizing efficiency, surface hydrophobicity, and suitability for printing, coating, or lamination processes.
Key Features
- Stainless steel test ring and base plate ensure dimensional stability, corrosion resistance, and long-term repeatability across high-volume laboratory use.
- Integrated compression spring mechanism delivers consistent, operator-independent clamping force—eliminating variability from manual torque application and supporting GLP-compliant test execution.
- Ergonomic single-hand operation enables rapid specimen loading and unloading without compromising sealing integrity or test geometry.
- Quick-lock sample retention system secures specimens firmly within the 100 cm² test area while minimizing edge leakage and ensuring uniform water exposure.
- Modular roller stand (11 kg) provides stable, vibration-damped positioning during drainage and handling, reducing operator-induced error and improving workflow efficiency in QC laboratories.
- Compact footprint (240 × 120 × 200 mm) and lightweight construction (3 kg net) facilitate integration into constrained benchtop environments without sacrificing mechanical rigidity.
Sample Compatibility & Compliance
The C0005 is optimized for medium-to-low absorbency papers and boards—including coated offset papers, packaging board, corrugated linerboard, and solid bleached sulfate (SBS) substrates. It is not suitable for highly porous or structurally weak materials such as newsprint, blotting paper, tissue, or uncoated writing papers, where capillary disintegration or fiber migration may invalidate mass-based interpretation. All test procedures adhere strictly to the geometric and procedural constraints specified in ISO 535:2014 (determining water absorptiveness — Cobb test), TAPPI T 441 om-18 (Cobb test for paper and paperboard), and AS 1301.411s (Australian Standard for Cobb value determination). Instrument design supports traceable calibration via certified reference weights and documented maintenance logs—key requirements for ISO/IEC 17025-accredited testing laboratories.
Software & Data Management
The IDM C0005 is a manually operated, analog-digital hybrid instrument requiring external analytical balance integration for mass measurement. While it does not incorporate embedded firmware or proprietary software, its operational protocol is fully compatible with LIMS and ELN platforms via standard CSV or Excel data import. Users may implement audit-trail-enabled digital worksheets aligned with FDA 21 CFR Part 11 requirements when paired with validated balances and electronic lab notebooks. Calibration records, environmental condition logs (temperature/humidity per ISO 187), and test reports can be structured to satisfy internal QA documentation standards and external regulatory audits (e.g., GMP or FSC-certified packaging production lines).
Applications
- Quantifying surface sizing effectiveness in paper mills during process optimization and grade development.
- Verifying compliance of packaging substrates with end-use specifications for liquid containment (e.g., food-grade cartons, beverage carriers).
- Supporting R&D of barrier-coated papers by correlating Cobb values with ink adhesion, print mottle, and varnish uptake performance.
- Quality control screening of incoming rolls prior to converting operations such as flexographic printing or hot-melt lamination.
- Inter-laboratory round-robin testing under ISO/IEC 17043 proficiency schemes for paper physical testing competence assessment.
FAQ
What is the nominal test area of the C0005 Cobb tester?
The test area is precisely 100 cm² (equivalent to 2500 px² at standard screen resolution), conforming to ISO 535 and TAPPI T 441 geometric requirements.
Can the C0005 be used for newsprint or tissue paper?
No—these materials exhibit excessive capillary wicking and structural collapse under water contact, violating the test’s assumption of dimensional stability; alternative methods (e.g., Klemm or STR tests) are recommended.
Is temperature and humidity conditioning required before testing?
Yes—per ISO 187, specimens must be equilibrated at 23 ± 1 °C and 50 ± 2 % RH for ≥24 h prior to testing to ensure reproducible moisture content baseline.
Does the instrument include a built-in timer or water level sensor?
No—the C0005 relies on external timing devices and manual water dosing; this design prioritizes mechanical simplicity, regulatory transparency, and ease of validation over automation.
How often should the stainless steel components be cleaned and inspected?
After each test series, rinse the ring and base plate with deionized water and dry thoroughly; inspect for scratches or pitting quarterly using calibrated surface roughness gauges to maintain seal integrity.
