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CAM 200 CAM 200 Excellence in Surface Chemistry Optical Contact Angle/ Surface Tension Meter The Modular CAM 200 – Optical Contact Angle and Surface Tension Meter Applications • Surfactants, Soaps & D[.]
Excellence in Surface Chemistry CAM 200 Optical Contact Angle/ Surface Tension Meter The Modular CAM 200 – Optical Contact Angle and Surface Tension Meter KSV's CAM 200 is a fully computer controlled instrument based on video capture of images and automatic image analysis for measuring static or dynamic contact angles, surface or interfacial tensions of liquids, surface free energies, and absorption of liquids into porous materials The open and user friendly design of CAM 200 makes it just as suitable for measurements in the R&D lab as on a production line Applications Key Features • • • • • • • • • • • • Easy and automatic determination of surface/interfacial tension, contact angles, absorption and surface free energy • Static and dynamic measurements • Complete Curve fitting based on Young - Laplace equation • LED based background lighting • WindowsTM software for 2000/XP • Image based trigger • Highly accurate Surfactants, Soaps & Detergents Emulsions Polymers Pharmaceuticals Sprays, Paints & Coatings Paper, Film & Ink products Cosmetics Textiles Food industry Surface treatments Cleanliness www.ksvltd.com Why measure contact angle and surface tension? In order to meet the challenges of the future in improving our quality of life and protecting our environment, the development of new surfaceengineered materials and products are the focus of many fields of todays scientific research Precise characterisation of material surfaces and liquids plays a vital role in development of new, better performing products with improved qualities Measurement of contact angles and surface/interfacial tensions provides a better understanding of the interactions between solids and liquids or liquids/liquids These interactions play a key role in understanding adhesion, material wettability, biocompatibility, lubricity of solid surfaces as well as the wetting, washability, spreading and adsorption of liquids Contact angle and surface/interfacial tension measurements provide the information needed for the development and modification of liquid and solid surfaces using todays sophisticated surface engineering techniques Gas Contact angle Contact angle , θ, is the angle formed by a liquid at the three phase boundary where a liquid, gas and solid intersect The shape of the drop is controlled by the three forces of interfacial tension shown in the figure above θ is a quantitative measure of the wetting of a solid by a liquid, but it can also be used as a quality control measure in surface treatments and surface cleanliness Advancing Surface tension Surface tension, γ, arises because the molecules inside a liquid are affected by equal attraction forces in all directions, whereas the molecules at the surface have larger attraction forces towards the liquid than air A spontaneous contraction of the surface will therefore take place γ is an extremely sensitive indicator providing information on the washability, wetting, emulsification and other surface related processes Receding Static & Dynamic contact angles A sessile drop on a solid substrate gives the static contact angle The value of the static contact angle is found to depend on the recent history of the interaction An alternative method is to determine the Dynamic contact angles If the three phase (liquid/solid/vapor) boundary is in motion the angles produced are called 'advancing' and 'receding' angles The angles can then be determined by fitting an equation to the shape of the drop and calculating the slope of the tangent at the three phase boundary line Pendant drop The pendant drop method offer a convenient way to determine the surface tension of a liquid (gas/liquid interface) or the interfacial tension between two liquids (liquid/liquid interface) In the pendant drop method the surface/interfacial tension is determined by analyzing the shape of the drop of liquid hanging from the tip of a syringe The CAM200 fits the Young-Laplace equation to the drop image for calculation of surface and interfacial tensions This technique is extremely accurate and can be performed at elevated temperatures and pressures The Modular CAM 200 To the basic frame A choice of high-performance ca You add A manual or automatic sample st And a manual or automatic liquid www.ksvltd.com meras, of different speeds and magnification tage d dispenser and vertical positioner .and your instrument is ready! How to measure contact angle and surface tension with CAM 200? CAM 200 uses drop shape analysis for determining static or dynamic contact angles, absorption and surface/interfacial tensions of liquids The software for image analysis runs in all supported WindowsTM operating systems (2000/XP) Two factors are critical to the accurate measurement of contact angles and surface/ interfacial tensions by optical techniques; image quality and method of image analysis Image quality depends on the lighting source, lens and image capture of the instrument CAM 200 utilizes a unique monochromatic light source which generates the highest quality images with minimal sample heating The telecentric lens and high resolution CCD camera insure that these images are captured and transferred to the software without distortion or degeneration Image analysis is performed on the image stored to your computer The drop profile is extracted from the stored image with subpixel accuracy This profile is then curve fitted to the Young-Laplace equation The entire fitted curve may then be used to calculate contact angle or surface tension This approach represents an important advance over traditional calculation of these parameters from drop images Circular, polynomial and Bashford-Adams approaches (also available in the software) utilize only parts of the drop profile and may often produce erroneous results, especially for contact angles of large drops Sessile Drop (or Raised Drop / Bubble) • • • • • • • • Pendant Drop (Raised Drop / Bubble) • • • • Surface/interfacial tension, static and dynamic Critical micelle concentration Drop volume Interfacial rheology (with PDA 100 drop oscillator) www.ksvltd.com Advancing & receding contact angle Absorption Wetting Drop volume Drop area Length of the drop baseline Height of droplet Surface free energy CAM Series Software • • • • • WindowsTM software for 2000/XP Images and results stored to database for easy retrieval Live image on screen Frame-by-frame or movie playback of recorded images Liquid database with up to 100 entries Calculations • Contact angle (static, advancing & receding) • Surface / interfacial tension (pendant drop & raised drop) • Drop volume • Base length, height and area of drop Drop profile extraction and baseline • Special algorithm searches drop profile with sub-pixel accuracy • Automatic baseline detection Fitting methods Drop profile fitted with • Young-Laplace equation Provides exact calculation of all parameters, including contact angles of large drops • Bashforth-Adams For pendant drop measurements Database fitting depending on comparison of drop cross-section at two positions • Circle Rapid fit for contact angles Suitable only for small drops • Polynomial Used for contact angle calculations Especially for advancing and receding contact angle studies Surface free energy calculations Separate software offers different methods to evaluate surface free energy of solids: • Zisman Plot (critical surface tension) • OWRK • Simple Fowkes (geometric mean) • Extended Fowkes • Wu (harmonic mean) • van Oss Acid-Base • Equation of State • Schultz • Schultz Image based trigger • Recording can be turned on when drop touches the sample or leaves the needle • Triggering based on information seen on screen, no separate hardware is needed CAM 200 Features and Specifications Standard for all instruments is the convenient One Touch Dispenser (OTD) allowing simple and reproducible drop placement for contact angle measurements Specifications Measuring ranges Inaccuracy Maximum sample size Frame interval Max Measuring speed Resolution Camera Light source Computer requirements 180°, 0.01 999 mN/m ± 0.1°, ± 0.01 mN/m Unlimited x 150 x 150 mm ms*-1000 s 30, 60 or 100 full frames per second (*up to 420 fps at reduced resolution) 512x480 pixels (*512x150 pixels) Firewire CCD camera with telecentric zoom optics LED based background lighting PC with minimum 2GHz speed, 128 MB RAM, 16 MB RAM on up-to-date display card, WindowsTM 2000/XP with up-to-date service packs CAM 200 Accessories • A range of automatic dispensers - single liquid - liquids - disposable tip autopipette • Automatic dispensing positioner for contact angle measurement • Automatic sample stage with movement in one direction • Environmental and interfacial measuring chambers • Thermal measuring chamber (RT to 250°C) • Tilt stage (for adv and rec contact angle meas.) • Computer with pre-installed software • High speed camera • Filter to reduce effect of ambient light Optical Standards - lithographically printed glass slides for verifaction of calibration of pendant drop and sessile drop measurements Prepared according to ISO 9001:2000 standards and verified by certified national laboratory The Company KSV Instruments Ltd is a leading global provider of routine, research and characterization instruments for surface chemistry and Langmuir-Blodgett film applications Our headquarters are in Helsinki, Finland and we have offices in North America and Sweden and trained representatives throughout the world Interfacial Characterization With Sigma tensiometers and CAM Drop Shape Analysis contact angle meters and their various modifications KSV covers most of the known interfacial measurement techniques All instruments utilize the latest technological advances in measurement of surface/ interfacial tension of liquids as well as contact angles and surface free energies Langmuir Film Preparation and Characterization Ranging from manual, educational instruments to fully equipped high performance R&D grade multi/alternating layer LB-troughs KSV offers the widest range of Langmuir systems in the world KSV’s BAM (Brewster Angle Microscope) and ISR (Interfacial Shear Rheometer) are used for characterization of Langmuir and LB films in a wide variety of nanotechnology, biology and molecular engineering applications Dip Coating A wide variety of dip-coaters for exacting applications, from single manual dippers to automatic multiple dipping devices Process Control KSV makes a range of at-line (AL) and on-line (OL) process control tools for monitoring surface tension, temperature, pH, viscosity and conductivity An option also exists for automatic dosing of surfactants www.ksvltd.com KSV Instruments Ltd Höyläämötie 00380 Helsinki FINLAND Tel +358-9-5497-3300 Fax +358-9-5497-3333 e-mail: info@ksvltd.fi KSV Instruments USA P.O Box 192 Monroe, CT 06468 USA Tel +1-800-280 6216 +1-203-268-1745 Fax +1-203-459-0437 e-mail: ksvinfo@aol.com