KSV Sigma 700 Modular Surface Tensiometer
| Brand | KSV |
|---|---|
| Origin | Finland |
| Model | Sigma 700 |
| Measurement Range | 1–2000 mN/m |
| Force Resolution | 0.1 µN |
| Weight Resolution | 0.01 mg |
| Contact Angle Range | 0–180° |
| Contact Angle Resolution | 0.01° |
| Sample Stage Speed | 0.01–500 mm/min |
| Position Resolution | 0.015 µm |
| Temperature Control | –10 to 80 °C (thermoplastic jacket), –10 to 150 °C (stainless steel jacket), up to 250 °C (electric heating jacket) |
| Dimensions (D×W×H) | 24 × 33 × 62 cm |
| Weight | 20 kg |
| Power Supply | 85–264 VAC, 47–440 Hz |
Overview
The KSV Sigma 700 Modular Surface Tensiometer is an engineered platform for high-precision quantification of interfacial phenomena at liquid–air, liquid–liquid, and solid–liquid boundaries. Based on the Wilhelmy plate and du Noüy ring principles—complemented by advanced drop shape analysis for dynamic contact angle (DCA) and critical micelle concentration (CMC) determination—the system delivers traceable, reproducible measurements aligned with ISO 1409, ASTM D971, and ISO 19403 standards. Its modular architecture supports both static and time-resolved characterization of surface tension (ST), interfacial tension (IT), advancing/receding contact angles, hysteresis, and surfactant adsorption kinetics. Designed for laboratories requiring metrological rigor across R&D, quality control, and academic instruction, the Sigma 700 integrates thermal stability, mechanical isolation, and inert environmental control to minimize drift and artifact generation during extended measurements.
Key Features
- Modular measurement chamber with removable design—enables rapid reconfiguration for Langmuir trough integration, high-temperature studies (up to 250 °C), thin-film burst testing, or XY sample positioning.
- Thermally isolated microbalance assembly—minimizes conductive heat transfer between sample stage and force sensor, ensuring long-term baseline stability under variable temperature conditions.
- Automated Wilhelmy plate calibration and zero-point locking—performed without manual intervention, reducing operator dependency and enhancing measurement repeatability.
- Dual illumination system—LED-based chamber lighting optimized for high-contrast imaging during contact angle analysis; compatible with optional high-speed cameras for dynamic wetting studies.
- Inert gas inlet port and solvent-resistant PTFE-coated interior surfaces—supports measurements in controlled atmospheres and enables safe handling of aggressive solvents including chlorinated hydrocarbons and strong acids.
- Integrated stirrer with magnetically coupled drive—provides homogeneous bulk-phase mixing during CMC titrations without introducing electromagnetic interference or mechanical vibration into the microbalance signal path.
- Expandable sensor interface—supports direct connection of external Pt100 temperature probes and pH electrodes for correlated physicochemical parameter logging.
- Ergonomic front-panel薄膜 keyboard—enables standalone operation without host PC; includes dedicated controls for stage movement, illumination, stirring, and system status indication.
Sample Compatibility & Compliance
The Sigma 700 accommodates a broad range of sample geometries and physical states—from low-viscosity aqueous surfactant solutions to viscous polymer melts, volatile organic solvents, and heterogeneous suspensions. Its large working volume (≥210 g max sample weight) and wide-stage travel (500 mm/min speed, 0.015 µm position resolution) permit characterization of macroscopic coatings, fibers, porous membranes, and irregularly shaped substrates. All wetted components are chemically passivated: PTFE-coated chamber walls, Delrin® thermal jackets, and elastomeric fluid barriers protect electronics from accidental spillage. The system complies with IEC 61000-6-3 (EMC) and IEC 61010-1 (safety); its data acquisition architecture supports audit-trail-enabled operation per FDA 21 CFR Part 11 when paired with KSV’s certified software suite.
Software & Data Management
KSV’s OneAttension software provides unified control of tensiometric, goniometric, and thermoregulatory subsystems. It features real-time plotting of ST/IT vs. time, automated CMC detection via conductivity-coupled dilution protocols (with optional dual-syringe pump), and batch processing of contact angle sequences using ellipse-fitting and Young–Laplace algorithms. Raw force data is logged at ≥100 Hz with timestamped metadata (temperature, humidity, operator ID). Export formats include CSV, Excel, and HDF5 for third-party statistical analysis. Software validation documentation—including IQ/OQ protocols and electronic signature support—is available upon request for GLP/GMP-regulated environments.
Applications
- Surfactant formulation development—quantifying CMC, adsorption efficiency, and interfacial elasticity in detergent, pharmaceutical emulsion, and agrochemical systems.
- Biomaterial surface engineering—evaluating protein adsorption kinetics, cell adhesion propensity, and hydrophilicity/hydrophobicity gradients on medical device polymers.
- Coating and ink R&D—optimizing wetting behavior on low-energy substrates (e.g., PE, PP) and predicting leveling, cratering, and dewetting defects.
- Enhanced oil recovery (EOR) screening—measuring ultra-low interfacial tensions (<0.1 mN/m) between crude oil fractions and novel surfactant blends.
- Nanoparticle dispersion stability—correlating surface charge (via pH-controlled IT trends) with colloidal aggregation thresholds.
- Quality assurance in production—routine verification of batch-to-batch consistency in surfactant purity, solvent composition, and coating solution aging profiles.
FAQ
What measurement methods does the Sigma 700 support?
It supports Wilhelmy plate, du Noüy ring, pendant/sessile drop, and bubble pressure techniques—all accessible via hardware configuration and software selection.
Can the system operate unattended for overnight CMC measurements?
Yes—integrated syringe pumps, temperature stabilization, and automated data logging enable fully autonomous multi-hour experiments with configurable alert triggers.
Is the Sigma 700 compatible with non-aqueous systems such as molten polymers or ionic liquids?
With appropriate temperature jackets (stainless steel or electric heating) and corrosion-resistant probes, it supports measurements up to 250 °C and in chemically aggressive media.
How is traceability ensured for regulatory submissions?
All force sensors are factory-calibrated against NIST-traceable weights; calibration certificates, uncertainty budgets, and software validation reports are provided as part of the delivery package.
Does the system meet requirements for ISO/IEC 17025-accredited laboratories?
Yes—its documented measurement uncertainty, environmental monitoring capability, and electronic record integrity align with ISO/IEC 17025:2017 clause 7.7 (uncertainty) and clause 7.5.2 (data management).
