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SURFTENS ^UNIVERSAL – Overview

The contact angle meter SURFTENS^universal is an universal instrument for use in the laboratory as well as in production control.

It is characterized by the following features:

   

SURFTENS ^UNIVERSAL – applications

The modification of the wetting ability of technical surfaces by special surface treatments becomes more and more common in industry and research. For process characterization, adjustment of technological parameters and production control it is therefore absolutely necessary, to measure the surface free energy objectively and accurately before and after the modification process.

For this purpose a robust and easy to use contact angle measuring instrument is needed. SURFTENS^universal was developed to meet the needs in industry and research plus in production control. The operation is simple and for everybody possible after a short training.

The manual operation ensures an attractive price.

Thus SURFTENS^universal is used as well as in standard process control as well as in research and development.

In connection with the software "SURFTENS" the contact angle and the free surface energy of solids can be measured.

The comfortable documentation functions are a powerful help in quality assurance and research.

   

SURFTENS ^UNIVERSAL – the measuring software

	SURFTENS UNIVERSAL

Basically the measuring software "SURFTENS" makes possible the fully automatic measurement of the contact angle of a sessile drop by different fitting methods of the drop shape. The drop is automatically detected by image processing methods.

Specimen-dependent the contrast of the drop image can be critical for an automatic detection.

For such cases the software offers additional options for the drop detection like the manual setting of the baseline and the completely manual measurement of the contact angle by setting of measuring points on the monitor.

The scope of services is extended by additional measuring and service functions like:

The software contains an evaluation module (theory by Wu) for computation of the free surface energy of solids from the measured contact angles of 2 known measuring liquids.

By special software functions the drop volume is reproducible by 0,1 µl also with a manual dispensation system. As additional option the drop volume can be measured by the software.

A very useful feature is the acquisition of AVI-files from the live video stream. All measuring- and documentation functions are afterwards applicable to the complete film or any single image of the film.

The measuring results can be stored comfortable in protocols or the video image.

   

SURFTENS ^UNIVERSAL – measuring accuracy

The measuring accuracy is determined by using the live video image. A real drop of liquid changes itself permanently because of environmental influences like evaporation. Therefore the accuracy can be specified only by help of a contact angle standard.

The software has the following parameters:

   

SURFTENS ^PD – Software for measurement of surface tension of liquids

An optional extension is the software SURFTENS PD.

This software measures the surface tension of liquids using the pendant drop method.

The SURFTENS^universal  - standard configuration is sufficient for this measurement. Only the additional software module is necessary, which is offered as bundle in connection with the standard software.

   

SURFTENS ^UNIVERSAL – additional hardware

The basic configuration can be extended by different hardware moduls. Currently the following additional modules are available:

1) Double dispenser

The double dispenser consists of 2 manual dispensation systems and is useful, if 2 measuring liquids are permanently used.

2) Automatic dispensation system
The automatic dispensation system provides a motorized and software controlled dispensation and setup of the drop.

The drop volume is programmable. It can be combined with a motorized x/y-stage, which allows contact angle mappings of large specimen.

3) Tilting stage

In combination with SURFTENS^universal a tilting stage is available. The specimen is tilted together with the drop of the measuring liquid (sessile drop).

Not only the specimen is tilted, but the complete instrument. Therefore the live video image shows only a change of the left- and right-side contact angle dependent from the tilting angle. Starting with a horizontal positioned drop and symmetric contact angles on both sides, the drop contour shifts with advancing tilting angle. The drop changes its form because of the gravitation proportional to the tilting angle. In connection with the measuring software this effect can be logged and displayed graphically and in a protocol.

The tilting stage is operated manually with a reproducibility of 1°. The input of the tilting angle in the software is made manually. Finally the software provides a graphic of the left- and right-side contact vs. tilting angle.

The tilting stage can also be used for testing the roll-angle of a sessile drop.

4) Contact angle standard

The contact angle standard is a glass substrate, on which by use of a photolithographic process several contact angle pictures are displayed. The design data (CAD-data) provide the contact angle for each picture. Because of the high accuracy of the manufacturing method the images have exactly the estimated contact angles without any error.

Therefore the contact angle standard is a perfect specimen for verifying the accuracy of the measuring instrument.

5) Thermal chamber

The thermal chamber enables contact angle measurements with temperatures up to 80°.

The temperature is software controlled and is transferred in the measuring results automatically.

   

SURFTENS ^UNIVERSAL – Technical data

This features are for the standard equipment and can be adapted to other technical requirements.

The technical parameters are subject to change without notice.

Binding are the technical specifications as per quotation.

   

SURFTENS ^UNIVERSAL – Mehr Information

SURFTENS (PDF)