The BP-D5 is a fully automatic bubble pressure tensiometer for measurement of the dynamic surface tension of aqueous surfactant solutions in a time function or at a fixed surface age. For monitoring the bubble formation, the pressure voltage waveform is displayed in real-time and bubble formation is made visible by a synchronized built-in stroboscope.
Temperature-dependent measurements can also be carried out with the built-in jacket type stage and thermometer.
Display of the pressure voltage waveform
For obtaining valid measurement data, the air bubbles generated from the submerged glass probe must be clearly separated from each other. The real-time display function of the waveform helps to monitor the condition on the lifetime and allows for appropriate adjusting of the air flow rate.

Extrapolation according to Hua & Rosen
Based on the recorded surface age raw data, the average values will be calculated and displayed in a graph. Data of up to 11 measurements can be directly compared if they share the same surface age range
Using the fitting method according to Hua & Rosen the surface tension right after bubble generation and at equilibrium are extrapolated.

Features
-
"One-click" fully automated operation
- Surface tension against surface age (from 20 to 5000 ms) chart is computed and plotted automatically
- Measurement of the dynamic surface tension at a specific surface age from 20 to 1000ms.
- Real-time display of the bubble pressure waveform to monitor the conditions of the bubble generation
- Extrapolation of the averaged raw data according to a method suggested by Hua & Rosen
- The bubble generation from the capillary is made visible by a synchronized built-in stroboscopic lamp
- Built-in jacket-type stage and platinum resistance thermometer for measurements in the range of +10 to 70 ℃
- Ultrasonic cleaner for cleaning the glass probes
Options
Hardware
- Air tank for a surface age range from 20 to 15.000 ms.
Applications
- Determination of the characteristics of surfactants, such as concentration, lifetime, and dynamic surface tension
- Dynamic surface tension and instant wettability of inks and coating fluids
- Determination of the absorbing rate of surfactants to control the dynamic surface tension
- Instant forming of microdroplets with regards to aerosols and emulsifiers
- Determination of instant foaming of detergents and fire extinguishing fluids
Specifications
BP-D5 | ||
Measuring methods | Maximum bubble pressure method | |
Measuring range | 10 to 100 mN/m | |
Resolution | 0.01 mN/m | |
Accuracy1) | 0.5 mN/m | |
Surface age range of dynamic surface tension | in a time function: 20 to 5.000 ms, optional: 20 to 15.000 ms at a fixed surface age: 20 to 1.000 ms |
|
Sample volume | about 80 mL | |
Sample viscosity range | 0.5 to 10 mPa・s | |
Sample stage operation | by software-controlled pneumatic cylinder | |
Air supply pressure | 0.4 to 0.7 Mpa | |
External dimensions (WxDxH) |
320 x 315 x 475 mm | |
Approximately weight | 18.5 kg | |
Electric power: Voltage Frequency Power consumption |
AC 100-240 V 50/60 Hz 50 W 80 VA |
|
Operating environment |
temperature: +10 to +35 ℃, humidity: 30 to 80 %RH (non-condensing) positioned away from sources of electrical noise and vibration |
1) Accuracy is the repeatability in terms of standard deviation based on the manufacturer’s prescribed conditions