Optical Tensiometers THE COMPLETE RANGE OF CONTACT ANGLE METERS / GONIOMETERS. theta. theta lite. theta qc. Attension Optical Tensiometers

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1 Optical Tensiometers THE COMPLETE RANGE OF CONTACT ANGLE METERS / GONIOMETERS theta theta lite theta qc Attension Optical Tensiometers 1

2 Optical Tensiometers are used in research, development and quality control for the study of surfaces and interfaces. Primarily developed for the of contact angles and surface free energy, they are also capable of determining surface tension, interfacial tension and interfacial rheology. Applications Attension Optical Tensiometers are versatile instruments used to characterize material surface properties and interfacial interactions between gas, liquid and solid phases. Also known as goniometers or contact angle meters, they are instruments of choice to characterize surfaces and surface treatments for research, development and quality control. They enable investigation of material properties such as: Measurements Attension Optical Tensiometers can measure: static contact angle dynamic contact angles surface free energy surface tension interfacial tension interfacial rheology (viscoelasticity) wettability adhesion homogeneity spreading cleanliness printability sorption emulsion and foam stability Key concepts Surface free energy Surface tension liquid gas Contact angle Application examples solid Optical tensiometers are used in a great variety of industries such as biomaterials, chemicals, pharmaceuticals, electronics, foods, energy, environment, paper and packaging. Applications include: Wettability of functional surfaces Nanoengineered functional surfaces are studied for a wide range of applications. For instance, superhydrophobic self-cleaning coatings can be utilized in solar cells and windows. Contact angle is the method used to define the superhydrohobicity and functionality of these novel surfaces. Surface homogeneity and cleanliness Wettability, absorption and spreading of liquids on coated surfaces can be investigated with contact angle versus time curves. Surface free energy and contact angle mapping help you to characterize your coating homogeneity and cleanliness. Surface tension, γ A molecule in the bulk of a liquid experiences equally attractive forces in all directions, but at the surface there are more attractive forces in the direction of the bulk than away from it. This reduced attraction at the liquid-gas boundary gives rise to the measurable property of surface tension. At the liquid-liquid phase boundary, it is referred to interfacial tension. Contact angle, θ Surface tension alone does not explain the shape of a drop on a solid. Interactions between the liquid and solid can be attractive or repulsive. When attracted by the solid, the liquid forms a drop with low contact angles (θ < 90 ). If repelled, the contact angles are high (θ > 90 ). The contact angle is a quantitative measure of the wetting of the solid by the liquid. Adhesion Wettability can be used to estimate thermodynamic adhesion. For instance, knowing that water contact angle s correlate with cell and bacterial adhesion, one can evaluate surface biocompatibility. θ > 90 hydrophobic solid θ < 90 gas gas gas liquid θ liquid θ hydrophobic solid θ = 90 liquid hydrophobic solid θ Emulsion stability (interfacial rheology) Optical tensiometer with pulsating droplet module is used to investigate viscoelasticity of adsorbed molecular layers. This makes it possible to study surfactant kinetics and emulsion stability. Dilational interfacial rheology is a commonly used method to study the crude oil separation process. Surface free energy Surface free energy (SFE) is surface tension for solids. Surface free energy is defined as the sum of polar and dispersive components indicating the nature of intermolecular interactions at the interface. 2 Attension Optical Tensiometers

3 Technology A few of our customers An optical tensiometer records drop images and automatically analyzes the drop shape. The drop shape is a function of the surface tension of the liquid, gravity and the density difference between sample liquid and surrounding medium. On a solid the drop shape and the contact angle also depends on the properties of the solid (e.g. SFE, topography). The captured image is analyzed with a drop profile fitting method in order to determine contact angle and surface tension. Surface free energy can be calculated by performing contact angle s with several known liquids. As an optical method, the precision of optical tensiometers depends on the quality of the pictures and the analysis Software. Attension Optical Tensiometers utilize a high quality monochromatic cold led light source to minimize undesirable sample evaporation. Image quality is guaranteed by a high-resolution digital camera, quality optics and the accuracy of the drop fitting method. Universities MASSACHUSETTS Institute of Technology University of California, BERKELEY University of CAMBRIDGE HARVARD University University of TORONTO YALE University University of BRITISH COLUMBIA MCGILL University University of CALIFORNIA, San Diego SEOUL National University UPPSALA University TOHOKU University Hebrew University of JERUSALEM STONY BROOK University University of HELSINKI DELFT University of Technology CHALMERS University of Technology UCL (University College London) University of BARCELONA University of AARHUS Katholieke Universiteit LEUVEN NANJING University KTH, ROYAL Institute of Technology Companies and research institutes sessile drop A highly accurate and reproducible optical method suitable for contact angle. pendant drop The pendant drop is used for highly accurate surface and interfacial tension s. meniscus The meniscus technique is used to measure contact angles of fibers or plates. 3M Akzo Nobel Amgen Avery Dennison BASF Canon Dow Corning Eastman Kodak E. I. Du Pont De Nemours & Company ExxonMobil FujiFilm Hewlett Packard IBM INRA Johnson & Johnson Lexmark Medtronic Monsanto Company NASA Langley Research Center Nissan Nokia Novo Nordisk NTT Omron Petrobras Randox laboratories Rhodia Ricoh Rohm and Haas Samsung Sandvik Seksui Chemical Statoil VWR International Attension Optical Force Tensiometers 3

4 Product range The Attention Optical Tensiometer offering is designed to fit a wide range of applications from advanced research to quick quality control. Theta Optical Tensiometer Theta harnesses the power of full automation to deliver unparalleled performance and ease of use for the most demanding research and industrial applications. It is able to perform the complete range of s, namely static contact angle (sessile drop method, captive bubble method, meniscus method), dynamic contact angle (tilted drop method and sessile drop method), surface free energy, surface/ interfacial tension (pendant drop method, reverse pendant drop method) and interfacial rheology (dilational rheology by the oscillating drop method). The drop volume is also measured. Theta is operated with the OneAttension Software, providing superior drop shape analysis, live, multiple options as well as a logical and friendly user interface with no equivalent on the market. Theta comes with Software including all functionalities. Please read the dedicated Software section on page 6 for a complete description. Theta enables you to choose the level of automation and the advanced functionalities that you need for your application. The Theta modularity and extensive list of accessories enable you to upgrade or change solution as your needs evolve theta Build your Theta 1. Select the speed of your Digital Video Camera (dvc) The 60 fps (frames per second) dvc can be upgraded to a highspeed 420 or 1550 fps camera. All are supplied with x 6.5 zoom. 2. Select either a motorized or manual sample stage The sample stage can be moved in all 3 dimensions. This can be done with either manual with precision thumb screws or motorized for fully automatic s and programmable operations. 3. Select a motorized or manual motion for the liquid dispenser The liquid dispenser holder with manual movements is a clever dispensing-aid for placing a drop onto a substrate. The liquid dispenser holder with motorized vertical movement makes drop placement automatic. 4. Select either: (a) an automatic multi-liquid dispenser, (b) an automatic single liquid dispenser with a standard syringe or with a disposable tip syringe, (c) a manual single liquid syringe A multi-liquid dispenser is available, especially suited for automated surface free energy s. A standalone dispenser can be used to automate liquid dosing. Alternatively, the disposable-tip dispenser is particularly useful for repeated s with hard to clean substances. The manual precision syringe can be used to make drops quickly and precisely. The picoliter dispenser can generate drops from 20 to 380 pl and is particularly suited for small samples (e.g. fibers) and to study inkjet printability. 5. Select among Theta accessories and services Measuring chambers protect the sample from the environment. Measurement chambers are available non-thermostated, water bath thermostated (up to 100 c) or electrically heated (up to 250 c). Liquid/liquid chambers are designed for contact angle s in a liquid medium and can be thermostated. Pulsating drop module oscillates drop volume for rheological investigations. The volume is controlled throughout the experiment thanks to a unique automatic volume adjustment compensating evaporation. Tilting cradle for fully automatic dynamic contact angle s by the tilted drop method. Syringes, needles and pipette tips are available for quality liquid handling. You can choose from various gauge needles made from stainless steel or ptfe. Stainless steel hooked needles are also available. Disposable-tip dispenser tips are available made from polypropylene, pfa and parylene. Optical drop target is a certified slide with printed drop shapes at different contact angles and surface tensions. It is used for verification purposes. Active vibration isolation system and cabinet to eliminate disturbing vibrations caused by motors, traffic, air conditioning systems, etc. Cuvettes are available with specific holders, and are typically used in conjunction with a hooked needle for reverse pendant drop s. They can be placed inside measuring chambers. For complete module and accessory descriptions, please visit the Theta product page at 4 Attension Optical Tensiometers

5 Theta Lite Optical Tensiometer Theta Lite is a compact and robust optical tensiometer for simple and precise operations. It comes with a manual sample stage and liquid dispenser, making it a convenient entry-level instrument for routine s, educational use and quality control. It enables static contact angle (sessile drop method, captive bubble method) and surface free energy s. The drop volume is also measured. Surface tension and interfacial tension s (pendant drop method, reverse pendant drop method) are also available, as an option, as well as contact angle by the meniscus method. Theta Lite comes with the OneAttension Software which provides superior drop shape analysis, live as well as a logic and pleasant user interface with no equivalent on the market. Please read the dedicated Software section on page 6 for a complete description. Measuring chambers, liquid-liquid chambers, optical drop target (calibration tool), syringes, needles, cuvettes and other accessories are available to add capabilities to your Theta Lite. For complete accessory descriptions, please visit the Theta Lite product page at Theta QC Optical Tensiometer Theta QC is the first portable optical tensiometer to be completely standalone and wireless. It measures static contact angle and is developed primarily for quality control applications or for the characterization of large objects that cannot be measured with lab bench instruments. Very compact and light, Theta QC can be carried with one hand and easily positioned onto a substrate for analysis. The integrated dispensing syringe is easy to extract for filling, cleaning or exchange. The integrated touchscreen makes operations easy and convenient. Multiple settings can be controlled, including the drop volume. When initiating the, a droplet is automatically deposited from below the instrument. The needle can be visualized from the Viewfinder window for accurate placement. Following deposition, a picture of the drop is taken. It is possible to set a delay between the drop deposition and the recording. The right contact angle, left contact angle and average contact angle are displayed on the screen. Data is saved in the instrument and can also be transferred wirelessly (WLAN) or via a cable connection to an external computer. For additional product information, please visit the Theta QC product page at theta lite theta qc Attension Optical Tensiometers 5

6 OneAttension Software The OneAttension Software provides unrivalled performance and ease of use to all computer controlled Attension tensiometers. It features: Recipe manager: default recipes include pre-defined experimental parameters for standard s, saving time at start-up. The user can decide to create custom recipes to match his/her needs. Recipes can be stored for further use for quick and repeatable operations. Live analysis: the data is plotted and analyzed in real-time enabling easy monitoring of results (deeper analysis can be performed off line when required) or simple pre-testing of experimental parameters. OneAttension software: pulsating drop Best-in-class user interface: the simple and logical Software interface allows efficient and convenient operations, leading to easy familiarization and time savings. Flexible data handling: any groups of data points can be selected, plotted and analyzed. Data can be assigned to any axis and be transformed into logarithmic scale. Data export: results are exported to an Excel, CSV or other file formats in a few clicks. User manager: set the desired level of privacy on experiment recipes and results. OneAttension software: easy and powerful data handling and plotting Available methods: Flexible software platform: easy implementation of customized features and functionalities. OneAttension for Optical Tensiometers: Superior analysis of drop shapes: subpixel accuracy drop fitting using the Young-Laplace equation, the reference method, first brought to optical tensiometry by Attension. Bashforth-Adams, Circular and Polynomial methods also available. Automation: automatic base line detection and drop shape fitting for convenience, repeatability and quick s. When choosing Theta motorized dispenser and sample stage, it is possible to program fully automatic contact angle s. Flexible settings: it is possible to control the number of frames per second, the dispensed volume*, the drop deposition locations*, the deposition mode (type coordinates, zigzag, record dispenser position)* and many other parameters to tailor operations to your needs. Contact angle on curved surfaces: easy contact angle on circular or near-circular surfaces (e.g. contact lenses). Compatibility: OneAttension is also compatible with older Optical Tensiometers from Attension such as CAM 200, CAM 101, CAM 100 (systems equipped with a firewire camera). Contact your closest Attension representative to upgrade your Software. Sessile drop for static contact angle of a liquid droplet Advancing drop for dynamic contact angle Meniscus for static contact angle with a fiber/rod Pendant drop for surface and interfacial Pulsating drop* for dilational interfacial rheology Tilted drop* for dynamic contact angle s Receding drop for dynamic contact angle Captive bubble for static contact angle of a gas bubble Reverse pendant drop for surface and interfacial advancing angle receding angle * available only with Theta Optical Tensiometer 6 Attension Optical Tensiometers

7 Specifications Theta, Theta Lite and Theta QC main specifications are listed in the table below. For all additional questions, please contact your nearest Attension representative which can be found from our website theta theta lite theta qc Available Measurements Static contact angle Dynamic contact angle automatic manual Surface/interfacial tension Interfacial rheology Surface free energy Zisman Plot, OWRK/Extended Fowkes, van Oss Acid-Base, Wu, Neumann s Equation of State, Schultz 1 and 2 Available Measurement Methods Sessile drop Captive bubble Pendant drop Reverse pendant drop Meniscus Dynamic contact angle automatic manual Pulsating drop Hardware Measuring range (, mn/m) , , Accuracy (, mn/m) ± 0.1, ± 0.01 ± 0.1, ± 0.01 ± 0.1 Maximum sample size (mm) unlimited * 95 * 180 (with stage) unlimited * 50 * 200 (with stage) unlimited Frame interval 0.65 ms 1000 s 17 ms 1000 s Maximum resolution (pixels) 640 * * * 480 Maximum measuring speed (fps) Camera Firewire digital camera with zoom Firewire digital camera Digital camera Light source led based background lighting led based background lighting led based background lighting Field of view (diagonal in mm) Dimensions (basic frame) (mm) h 590 * w 200 * l 740 h 310 * w 130 * l 495 h 152 * w 125 * l 119 Weight (basic frame) (kg) Power supply (vac) (3.7) Frequency (Hz) Drop Profile Fitting Method Young-Laplace (ca, st/it, m) Bashforth-Adams (st/it) Circular (ca) Polynomial (ca, m) Software Provided Software OneAttension OneAttension Data transfer System requirements Recommended system 2 ghz processor, 1 gb ram, 40 gb hard disk drive (20 gb free), requirements Operating system requirements 1024 * 768 resolution, 1 usb port, 1 Firewire port or 1 pci slot Windows 7 (32 or 64 bit), Windows Vista (32 bit), Windows XP SP3 (32 bit) : available : not available/not applicable ca: contact angle st/it: surface tension and interfacial tension m: meniscus Attension Optical Tensiometers 7

8 Services Attension offers a range of services to assist you throughout the lifecycle of your instrument: Pre-testing: Attension can conduct pre-studies to ensure the most suitable instrument is selected for your application. Installation and user training: installation and user training can be performed at your site. Additional training can be provided at anytime at your research location or at any one of our Attension Laboratories. Maintenance and repairs: Attension understands the importance of your research and we are committed to insuring that your instrument is running at its optimal performance level. With an Attension service plan you can be proactive and choose when your service takes place. This will insure your laboratory runs at its peak efficiency and the investment in your instrument will be maximized by extending its lifetime. Separate repair services are also available. Other Attension Tensiometers Force Tensiometers for surface tension, interfacial tension and automatic critical micelle concentration s. Attension Sigma Force Tensiometers can also measure dynamic contact angle, surface free energy, powder wettability, sedimentation and density. Bubble Pressure Tensiometer for dynamic surface tension s. Attension BPA-800P Bubble Pressure Tensiometer also measures bubble lifetime, bubble deadtime, the hydrostatic pressure and the effective adsorption time. For more information on Sigma Force Tensiometers and BPA-800P Bubble Tensiometer please contact your Attension representative or read the product brochures available from our website Specifications and appearance are subject to change without prior notice. Biolin Scientific shall not be liable for any errors in this document. Contact information Availability Attension Biolin Scientific Tietäjäntie 2 fin Espoo, Finland tel fax info@attension.com Attension products and services are provided through Biolin Scientific and its competent network of distribution partners. For a list of relevant contact details, please visit 8 Attension Optical Tensiometers