OCA 10/OCA 20 - Asi-team

O C AO p t1i c0/OCA 20al Contact Angle Measuring Instruments

11Liquid drop on apartially reflecting sample2OCA 10 with multiple dosing unitMD and 4 manual syringeunits MSO C AT h e1m0a n u a l c o n t a c t a n g l e m e a s u r i n g i n s t r u m e n t2experience in these measurement techniques. We would likeyou to benefit from this knowledge that is incorporated intoour technical instruments.How measuring andapplication technology acttogether, optically.In a variety of technical applications the wetting behavior ofliquids towards solid surfacesplays an essential role. Whetherin the production and processingof paints and varnishes, in thedevelopment and productionof composites, when gluing ordissolving materials or in thebio-compatibility of medical implants. In all these applications,an exact determination of thestatic or dynamic contact angle,as well as the surface and interfacial tension of liquids andsolids is needed.The most up-to-date optics, precise mechanics and a high resolution video measuring technique ensure that the user of DataPhysics contact angle measuringinstruments obtains the rightview in any measuring situation.Our development engineers benefit from many years practical2Contact angle measurement –From theory to practiceToday, modern contact anglemeasuring instruments can domore than just determine thecontact angle. They permit theprecise determination of surfaceor interfacial tension of liquidsas well as the surface free energies of solids. Beside the standard evaluation methods, e.g.Owens-Wendt, Wu, Schultz, Zisman, evaluations according tonew and extended theories e.g.,Acid-Base, Extended Fowkes,Equation of State, have been included in the software developedfor Windows 9x/NT available forthe OCA 10 and OCA 20 instruments.The starting point is always thesimplified Young-Dupré's equation for the balance of forces inthe so-called three phase pointbetween liquid, solid and vapor.The smaller the measuredcontact angle Θ , the better isthe wetting between liquidand solid.Much more detailed statementscan be made by calculationthe dispersion and nondispersion force contributions to thesurface tension or to the surfacefree energy of the solids. Theobtainment of this additional information is made possible bythe comprehensive test liquiddatabase of the DataPhysics SCAsoftware for the contact anglemeasuring instruments that arepart of the OCA construction kit.

Your application – Our challengeSome important applicationsfor measuring contact angle andinterfacial tension with theOCA systems are: the painting, printing andcoating of metals, plastics andpapers the development of high performance composites the determination of the surface cleanliness of semi-conductor wafers and video screenglass substrates the development of cosmeticand pharmaceutical products,e.g. pastes and creams or powdercoatingsThe smallerand six-fold power zoom can beeasily adjusted on the measuringlens with one hand. The particularly high-contrast image qualityof the OCA lenses coupled withthe homogeneous back lightingwill impress every user. Thecontact angle measuring resultscan then be documented andevaluated with the SCA 10*) software.Temperature measurementand display includedThe measurement of the precisetemperature is important for allthermodynamic quantities, DataPhysics has integrated temperature measurement and displayin the range from -10 to 400 Cin all OCA systems**).Precise sample positioningand dosingAdjustable in three degrees offreedom, the sample stage canbe easily adjusted for measuringall angles of the sample. Additionally, the dosing needles forthe test liquids can be individually adjusted vertically and horizontally to the optical axis. Formanual dispensing of up to fourliquids, the OCA 10 user canchoose between single and multiple dosing units. the surface finish and textilecleaning the development of surfaceactive plant protectives the optimization of the adsorption behavior of absorbentpapersModular and user-friendly –The OCA 10The contact angle measuring instrument OCA 10 permits thedetermination of the static contact angle by means of a precision protractor eyepiece. FocusUpgrades and extensionsIn addition, temperature controlsand special sample stages, forinstance for wafers, foils, textilesand printing cylinders are available from the OCA constructionkit. The OCA 10 and OCA 20 aredesigned for maximum customer-specific adaptation of thebasic units and the system components. With the versions OCA10L and OCA 20L, DataPhysicsoffers solutions even for unusualsample shapes and sizes.the measured contactangle Θ, the betteris the wetting betweenliquid and solid.343Thermal chamberTFC 100 with multipledosing unit MD4Manually tilting baseassembly*) optional**) resistance temperature probes Pt 100 optional3

121Suspended liquid drop to be evaluatedwith the Pendant Drop method2Fiber bundle with liquid lamella to calculatethe contact angle3OCA 20 with multiple dosing unit MD,4 electronic syringe units ES and software SCA 22for calculation of the surface andinterfacial tensionD a sV i dOe o -Cs uA20pported measuringwith method and precisionIncreased performance –The OCA 20With the video-supported contact angle measuring instrumentOCA 20 we go a few steps furher.The micro-controller module inthe OCA 20 allows automation ofthe liquid handling as well asmeasurement. Up to four motordriven dosing units are easilyconnected to the OCA 20 and thecontrol software. The staticcontact angles and the dynamicwetting angles i.e. advancingand receding angles, can bemeasured with these devicesusing a fixed dosing volume. Forparticularly small or large contact angles, the system providesan increased measuring accuracy as well as an automatic detection of the solid surface.The Plug and Play principleMicroprocessors are used in theOCA 20 to manage complextasks even in the smallest components, like for instance in theelectrically driven sample stagesfor wafers up to a diameterof 300 mm, in the positioningdrives for the program-controlled immersion of solids as43well as in the tilting stages formeasuring the contact anglehysteresis. They are connectedto the basic unit in seconds andare immediately ready for use.Via a flexible and quick bus system a master controller monitors the communication between the individual systemcomponents and of course, thecorrect timing. The OCA electronics can always be extendedby adding new components.At DataPhysics, we take the Plugand Play principle seriously.

Methodical applicationWhatever substances you examine, whether they are surfactant solutions, liquid phasesof micro-emulsions or moltenmetals and polymers, the OCA 20will calculate the surface andinterfacial tension from the contours of pendant and sessiledrops as well as of liquid lamellae on plates, bars and fibers.How?The equilibrium shapeof liquid drops is described byt h e Yo u n g - L a p l a c e e q u a t i o n3Efficient softwareIntuitive software with manygraphic elements is useful whensetting up a test method, whentaking measurements and inthe evaluation and analysis ofresults.Our software engineers have awealth of experience in thedevelopment of the softwarepackages for the SCA series,specializing in accurate and reliable methods of drop contourevaluation using statistical error analysis. Every stage ofupgrade from SCA 20 to SCA 23enables a new level of analysisto be carried out, according toyour requirements.Our application specialists willanswer this question for you,either by visiting your premisesor at the DataPhysics offices.They will also be glad to help yousolve your specific problems.Take advantage of our wide range of experience in surfacechemistry. We aim to assist youthrough the provision of application reports, by drawing yourattention to relevant specialpublications or with our database and e-mail informationservice via the Internet. Our goalis to understand your needs.445Standards foraccurate measurementsFor the contact angle measuringinstruments, DataPhysics offerthree series of optical standardsOCAS on glass carriers withstandard contours (pendantdrop and sessile drop) as well asliquid lamellae. Manufacturedusing precision methods tomeet ISO 9001, these standardswill ensure the user achievesaccurate results, every time.3SCA 20 and 21 – Contact anglemeasurement and calculation of thesurface free energy of solids4Display OCA 10/OCA 205Manual wafer stage WT 200M withmultiple dosing unit MD5

OCA construction kit6