OCA 15 Contact Angle Tool Standard Operating Procedure€¦ · OCA 15 Contact Angle Tool Standard...

OCA 15 Contact Angle Tool

Standard Operating Procedure

4D LABS Confidential

Revision: 1.0 — Last Updated: Oct.20/2009, Revised by Nathanael Sieb

Overview

This document will provide a detailed operation procedure of the OCA 15 Surface Analysis Tool.

Formal Training is required for all users prior to using the system.

Revision History

# Revised by: Date Modification

1 Nathanael Sieb 10/20/09 Initial release

2

3

4

5

Document No. 4DSOP000X

2

Simon Fraser University 8888 University Drive, Burnaby, B.C. V5A 1S6

E [email protected] T 778.782.8158 F 778.782.3765 www.4dlabs.ca

Table of Contents

General Information ................................................................................................................................. 3

Operation Procedure ................................................................................................................................ 4

1. Setting up the Instrument ................................................................................................................. 4

2. Setting up an Experiment ................................................................................................................. 5

3. Taking a Measurement ..................................................................................................................... 8

4. Data Analysis ................................................................................................................................... 9

5. System Shutdown........................................................................................................................... 11

Reference and Files ................................................................................................................................ 11

Contact Information ............................................................................................................................... 12

3



General Information

The OCA 15 tool is capable of determining many different properties of surfaces and liquids. The

tool has many hardware features included in it. The substrate holder can accommodate substrates up to

220 x ∞ x 70 mm (L x W x H) and can be moved in the x, y, and z direction. An electronically controlled

syringe is attached to the instrument in order to dispense a liquid onto a substrate. This syringe can be

moved in the x and z direction. Finally, there is also a digital video camera to view the substrate and liquid

drop. The camera can be tilted to examine the substrate and contains a 6-fold zoom lens and integrated

focus. The camera and syringe are both controlled through a software package contained on the asso-

ciated PC.

The SCA software provides the ability to measure dynamic and static contact angles. The internal

database contains the properties of many different liquids. These liquid properties and the measured con-

tact angles provide the user with the ability to calculate the surface free energy through an included soft-

ware package. This SOP will outline how to acquire a simple contact angle measurement. More advanced

features are discussed in the OCA 15 operating manual.

4



Operation Procedure

1. Setting up the Instrument

Turn on the OCA15.

Loosen the syringe clamp via the screw and move it out of the way.

Press the up arrow on the electronic dispenser.

Remove the syringe by loosening the thumbscrew and carefully removing it from the electronic dis-

penser.

Rinse the syringe and load it with one of the approved liquids (e.g. water). Always check that the liq-

uid you wish to use is approved. The use of non-approved liquids may permanently damage the sy-

ringe or the instrument.

Reinstall the syringe and tighten the thumbscrew. Do not over-tighten the screw, as it may break the

syringe.

Up/down arrows

Horizontal positioning

Vertical positioning

Syringe clamp

Thumbscrew

5



Lower the electronic dispenser (down arrow) and reattach the syringe holder clamp.

Place a substrate on the stage.

2. Setting up an Experiment

Ensure that the PC is turned on and logged in (4dlabs/4duser).

Open the SCA20 software.

If a Live Video window is not already open, go to FileNew WindowDrop Image Window.

In the drop down menu, select the appropriate Drop Type (e.g. Sessile drop).

If necessary, adjust the horizontal and vertical knobs on the needle holder as well as the zoom lens

knob on the camera to place the image of the needle tip in the upper-middle portion of the window.

6



Adjust the fine focus knob on the camera and illumination knob at the back of the light source to ob-

tain a sharp image of the needle.

Go to FileNew Window Result Collection Window.

Zoom Focus

7



In the Result Window, enter the correct parameters for the Drop Phase, Ambient Phase, and Solid

Phase.

Go to Edit general Preferences and click on “Result Window” to select the items to be displayed in

the Result Collection Window. For static contact angle measurement, “Calculation Error” and “Con-

tact Angle (Mean)” should be displayed.

8



Open the Device Control box by pressing .

Click on the “Dispense Unit” icon and enter required information for Dosing Rate and Dosing Volume.

3. Taking a Measurement

In the Dispense Parameter window, click on “Dispense”. When a drop hangs at the tip of the needle

and reaches its equilibrium state, raise the sample stage and catch the drop with the substrate.

Quickly adjust the illumination and magnification to obtain the sharpest drop image possible. The drop

image should cover approximately 2/3 of the window area. In case the substrate reflects the drop, a re-

flecting drop image should also be obtained by adjusting the illumination and magnification. The first

drop should always be served as a dummy drop to obtain the sharpest possible drop image. Proceed

with the real measurement for the next drop.

Place a droplet at a different spot on the substrate and take a snap shot by clicking on the “Snap” icon

as soon as the drop is placed on the substrate.

9



4. Data Analysis

When a sharp reflecting drop image is obtained, the baseline can be automatically determined by click-

ing on “Basis Line Detection” . In order for the detection to work correctly, the top line in the

window must be below the syringe. If automatic baseline determination is not satisfactory, use man-

ual baseline determination. Use the up and down arrows to move the baseline vertically, and the left

and right arrows to change the slope. Manual baseline determination is different for non-reflecting

drop image and reflecting drop image.

o Non-reflecting drop image: Place the baseline along the base of the drop where the drop is in

contact with the sample surface.

10



o Reflecting drop image: Place the baseline along the reflection line of the drop.

Click on the “Profile Extraction” icon so that the software automatically outlines the profile of the

drop image.

Click on the “CA-calculation” icon so that the software calculates the contact angle value.

If the Err (image fitting error of the contact angle calculation) in the Result Collection Window is larger

than 1, then place a new drop on a different location on the surface in order to adjust the baseline and

sharpness of the image resulting in a more accurate profile determination.

To collect more data, move to another position on the substrate.

Clear the current profile by clicking Erase All .

Click on the “Start Grabbing” icon to bring up the live image of the needle on the screen.

Snap a new drop image and acquire a new profile.

All of the data is compiled in the Result Collection Window.

11



The data can be saved or exported to a separate file.

5. System Shutdown

When your experiment is complete, save your data and shutdown the software.

After closing the software, wait 20 seconds, and then turn off the OCA 15.

Remove your substrate.

Do NOT turn off the computer.

Reference and Files

OCA Operating Manual.

12



Contact Information

Questions or comments in regard to this document should be directed towards Nathanael Sieb

([email protected]) in 4D LABS at Simon Fraser University, Burnaby, BC, Canada.

OCA 15 Contact Angle Tool Standard Operating Procedure€¦ · OCA 15 Contact Angle Tool Standard...

Documents

Transcript of OCA 15 Contact Angle Tool Standard Operating Procedure€¦ · OCA 15 Contact Angle Tool Standard...