Theta QCOptical Tensiometer

YOUR PORTABLE CONTACT ANGLE METER

FOR QUALITY CONTROL MEASUREMENTS OF:

- SURFACES AND COATINGS

- SURFACE TREATMENTS

- WETTABILITY

- ADHESION

Measurements

Theta QC Optical Tensiometer measures contact angles and is also known as a contact angle meter or goniometer. Contact angle measurement is a quick and reliable technique to obtain information on material properties such as:

· wettability· adhesion· homogeneity· surface free energy · spreading · sorption· cleanliness· printability

Industries

Theta QC Optical Tensiometer can be used in virtually any indus-try where surfaces and interfaces have a role to play. Please find below some of the main areas where optical tensiometry is used for quality control:

· paints and coatings· surface treatments· paper and packaging· surface engineering· printing· semiconductors· laminating· plastics

Technology

What is contact angle

Contact angle, θ, is a quantitative measure of the wetting of a solid by a liquid. It is defined geometrically as the angle formed by a liquid at the three phase boundary where a liquid, gas and solid intersect as shown below:

When attracted by the solid, the liquid spreads, forming a drop with low contact angles (θ < 90°). If repelled, the contact angles are high (θ > 90°).

The contact angle is determined by the interactions between the gas, liquid and solid phases. A change in one of the phase properties will lead to a change in contact angle measurable with Theta QC. Using a known liquid (typically water) and gas (typi-cally air) enables checking the solid properties. It is also possible to test liquid properties on a known surface.

Theta QC working principle

Theta QC deposits droplets from its integrated dispensing sy-ringe which can be easily filled with your desired liquid.

The drop can be visualized from the Viewfinder for accurate placement of the drop onto the solid sample.

Following deposition, a picture of the drop is taken. It is possible to set a delay between the drop deposition and the recording.

Theta QC analyzes the drop shape and calculates the contact angles formed between the liquid and the solid using the Young-Laplace equation, a standard in tensiometry. The right contact angle, left contact angle and average contact angle are displayed on the screen. Data is saved in the instrument.

Measurement data can be transferred wirelessly (WLAN) or via a cable connection to an external computer where the Theta QC Data Receiver Software is installed.

Theta QC Optical Tensiometer is a mobile contact angle meter enabling characterization of solid surfaces and liquid-solid interactions. It is primarily used for quality control measurements and characterization of large objects.

hydrophobic

= 90θ

solid

liquid

hydrophobic

> 90θ

solid

liquid

hydrophobic

< 90θ

solid

liquid

gas gas gas

θ θ θ

Theta QC is ideal for quality control of solid surfaces (cleanliness, homogeneity, surface free energy, etc.).

It also enables checking liquid behav-iour on solids (surface wettability, hydrophilicity, sorption, printability, etc.).

Viewfinder

The Viewfinder is a window enabling visualization of the drop placement on the sample surface using mirrors.

Product benefits

Outstanding mobility

Theta QC is a standalone tensiometer offering outstanding mo-bility: it is battery operated and completely wireless for optimal freedom in movement. Very compact and light, it can be carried with one hand and easily positioned at the desired location on the sample. This mobility makes Theta QC an instrument of choice for at-line quality control and process control. It is also a preferred solution to characterize very large samples that cannot be measured with conventional laboratory equipments.

Precise and repeatable scientific measurements

Theta QC is part of the Theta Optical Tensiometer range by At-tension. Our optical tensiometers have been used for more than twenty years and contact angle goniometry is a recognized tech-nique in research, development and quality control applications. Theta QC analyzes the drop shape and calculates the contact angles formed between the liquid and the solid using the Young-Laplace equation, now a standard fitting method first introduced to optical tensiometry by Attension. With Theta QC, the drop volume can be controlled and the deposition is automated for repeatability.

Simplicity of use

Attension gives importance to the ease of use of its instruments. The Theta QC touchscreen allows quick and convenient opera-tion of the instrument. Menus are intuitive and allow fast setting adjustements and measurement. The Viewfinder allows visualiza-tion of the drop deposition onto the sample. The dispensing sy-ringe can be easily changed for refill or replacement with another syringe, enabling you to use several liquids without contamina-tion. The measurement results can be transferred to a computer wirelessly or via a cable connection for easy storage of the data.

Examples of quality control applications

Quality control of plasma treated surfaces

Plasma treatment is used in number of industries to promote adhesion for example in extrusion coating, flexographic printing, painting and lamination. The homogeneity and efficiency of the treatment can be controlled by measuring contact angle.

Quality control of printability

In printing, Theta QC is used to control paper and plastic wet-tability with various inks. Theta QC allows the use of different liquids by simple syringe exchange.

Quality control of windshield coatings

Hydrophobic coatings deposited on windshields facilitate clean-ing and water flow. Coating homogeneity, cleanliness and wetta-bility can be checked by measuring contact angle with Theta QC.

Quality control of materials before lamination

Lamination is used to manufacture multilayer structures, in which the adhesion between materials is crucial. The Theta QC can be used to check the cleanliness and homogeneity of the lamination materials as well as the wettability of chosen adhesives.

Quality control of paint wettability

Quality of substrate batches may vary and thus affect final quality painted products. Contact angle measurement is an easy and simple way to check wettability and thus get indication of the paint-substrate adhesion.

Specifications

Measurement

Contact angle (°): 0-180 Resolution (°): ± 0.1

Footprint

Dimensions (mm): 119 (W) x 125 (L) x 152 (H) Weight (kg): 1.3

Battery

Autonomy (hours): 8Voltage (V): 3.7 Capacity (Ah): 5.2Power cable (Hz, V): 50-60, 100-240

Camera

Resolution (pixels): 752 x 476Magnification: 1

Viewfinder

Accuracy (mm): 1 x 1Dimensions (mm): 15 x 15

Liquid dispenser

Maximum volume (ml): 2Syringe material: Polypropylene (PP)Needle size and material: gauge 27, stainless steel and PP

Embedded memory

Storage capacity: 200 measurements

Available connections for data transferWLAN (wireless) Serial port (COM port)

Specifications and appearance are subject to change without prior notice.

Biolin Scientific shall not be liable for any errors in this document.

3101

2012

Contact information

AttensionBiolin ScientificTietäjäntie 2fin–02130 Espoo, Finland

tel +358 9 5497 3300 fax +358 9 5497 3333info@attension.comwww.attension.com

Availability

Attension products and services are provided to customers all over the world through Biolin Scientific in co-operation with a highly competent network of Distribution Partners. For a list of relevant contact details, please visit www.attension.com

Easy liquid exchange/reload

Syringes are used as liquid dispensers. They can be easily inserted into the instrument once filled with the desired liquid.