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Dyne Test Pen
Dyne Test Pen
Surface Tension Testing Pens / Corona Dyne Test Pens
The Dyne Test Pen is a valuable tool used in surface energy measurement and quality control processes. With its compact design and user-friendly features, it provides a quick and accurate way to determine the surface energy of various materials.
The Dyne Test Pen is widely used in industries such as printing, packaging, plastics, and coatings, where surface energy plays a crucial role in adhesion and bonding. It helps manufacturers ensure that their materials and products have the appropriate surface energy for optimal performance.
Using the Dyne Test Pen is simple. The pen contains a solution with a known surface tension value, typically expressed in dyne/cm. By applying the pen's tip to the material surface, the liquid wets the surface, and the behavior of the liquid indicates the surface energy of the material.
If the liquid forms a continuous film with no breaks or beads up, it suggests that the material has sufficient surface energy and is compatible with adhesives, coatings, or inks. On the other hand, if the liquid forms droplets or does not spread uniformly, it indicates that the surface energy is too low, which can result in poor adhesion.
The Dyne Test Pen comes in various surface tension values, allowing users to select the appropriate pen based on their specific requirements. The pens are color-coded or labeled with the corresponding dyne level, making it easy to identify and use the correct pen for a particular material.
This portable and handheld tool offers several advantages. Firstly, it provides a quick and on-the-spot evaluation of surface energy, eliminating the need for time-consuming laboratory tests. This allows for immediate decision-making during production processes, saving both time and resources.
Additionally, the Dyne Test Pen enables quality control by ensuring consistent surface energy across different materials or batches. By regularly testing materials throughout the production cycle, manufacturers can identify and rectify any issues, leading to improved product quality and customer satisfaction.
Moreover, the Dyne Test Pen is an economical solution compared to other surface energy measurement methods. It offers a cost-effective way to perform routine surface energy checks without investing in expensive equipment or complex testing procedures.
The versatility of the Dyne Test Pen extends to a wide range of materials, including plastics, metals, glass, ceramics, paper, and more. It provides reliable results for both non-porous and porous surfaces, making it suitable for diverse applications.
In conclusion, the Dyne Test Pen is a valuable tool for surface energy measurement and quality control. Its simplicity, portability, and accuracy make it an essential instrument for industries that rely on proper adhesion and bonding. By utilizing the Dyne Test Pen, manufacturers can ensure consistent surface energy, enhance product performance, and maintain high-quality standards.
INTRODUCTION & OVERVIEW
INTRO:
Are you achieving the dyne levels you need? Do you know the dyne level of your material prior to treating? Are you doing a dyne check before printing? Key to any surface treatment application is knowing your starting and ending treatment levels; Surface energy checking dynes pen can help you achieve this. BhumiChem’s Aalkemy Dyne pens provide a quick, safe and simple means of testing surface energy.
Test inks can be used to determine the surface energy / surface tension of solids made of plastics – metals – glass – ceramics. The adhesion possibility of the surfaces in particular for printing, bonding and painting should also be determined based on the wetting pattern.
In general, the ability of a substrate to anchor inks, coatings, or adhesives is directly related to its surface energy. If the substrate surface energy does not significantly exceed the surface tension of the fluid which is to cover it, wetting will be impeded and a poor bond will result. Thus, for most solvent based printing, plastics need to be treated to 36 to 40 dynes/cm; water based inks usually require 40 to 44 dynes/cm; some laminating and coating applications require surface energies of 50 dynes/cm or more. Clearly, surface energy must be assessed before printing, coating, or laminating is attempted.
Pens are available in 24-68 mN/m dyne levels.
For more technical queries you can contact us on bhavya@bhumichem.com
OVERVIEW:
The characterization of wettability and surface energy of solid materials has presented challenges to scientists and industrial technicians alike for as long as these attributes have been measured.
The fundamental problem is that no direct measurement technique exists: Instead, the vast array of experimental data available is based almost exclusively on the reaction of a liquid or liquids in contact with the solid, usually in the presence of either air or a saturated vapor of the test liquid. Thus, the nature of the test liquid affects the results as surely as the nature of the solid under investigation. Even the gas phase can have a significant effect, though it is usually less pronounced.
Two methods are widely used in science and industry. These are the dyne test, documented in ASTM Std. D2578 and the basis of all AALKEMY DYNE TEST products, which is based on the wettability of calibrated formulations and the contact angle test, which relies on measurement of the angle of contact that the test liquid (often reagent grade water) makes on the solid surface. Each has its own advantages, and there is a strong correlation between their results, but it is important to realize that differences in polarity, pH, and solubility parameters of either solid or liquid phase will affect the relationship between the two methods. Additional factors such as the evaporation rate of the liquid, surface topography of the solid, and incorporation of additives or contaminants at the liquid/solid interface will also influence results.
In industry, the commonest use of either test is to determine the efficacy of corona, flame, or plasma surface treatment. As long as the treatment is performed in an environment that includes oxygen, any of these methods effectively oxidizes the surface, increasing the polar component of its surface free energy. Generally speaking, the correlation between contact angle and dyne test results will increase as the surface energy of the solid becomes more influenced by polar, as opposed to dispersion, forces.
This means that in most cases there will be very good agreement between the contact angle and dyne solution results for treated polymers.
Dyne Testing — Applications and Tips
The dyne test has found countless applications throughout industry, in functions as varied as basic research, product development, process control, incoming inspection, finished product dispositioning, sales, and marketing. Typically, it measures the treatment level of polymers which have been exposed to flame, corona, or plasma surface modification; but, inevitably, after nearly 50 years, many less traditional applications have also been explored. Hopefully the following comments will be helpful.
• Whenever feasible, test with supplies, samples, and ambient temperature at 20o to 25oC. If this is impossible, it is advised that a test study be run to relate temperature variations to numerical results. Keep test supplies at ambient temperature at all times.
• Film extruders should test extensively — every roll from every machine without fail. Potential product liability and customer satisfaction losses far exceed the cost of an effective QC program. We strongly recommend using test fluids, preferably with the Aalkemy Dyne Applicator™ or a #3 metering rod. Alternatively, Aalkemy Dyne TEST Marker Pens can be used.
• Remember that dyne level decay is extremely rapid directly after corona treatment. A virtually immediate loss of 10 dynes/cm is possible! This is due to contact with process rolls (especially heated metal ones), surface blooming of additives and interfacial transfers between treated and untreated surfaces within the finished, wound roll. If you are a slitter, rewinder, or extruder, either test far downstream in the process, or increase your specification to account for greater losses before your customer tests at incoming inspection.
• It is often possible to identify patterns of treatment variation on a sample piece by doing drawdown tests. Methodical troubleshooting analysis will often lead back to the specific cause. For example, increasing treatment across the roll suggests the treater electrode is misaligned to the roll; periodic variations along the web may relate to non-concentricity.
• An easy test for back-treat on PE or PP is to use a 34 dyne/cm Aalkemy Dyne Test Marker Pen. Any wetting — even for less than two seconds — indicates some treatment.
• Test fluids or markers which have turned green or seriously lose their color density are no longer reliable. We guarantee against this up to the expiration date (five months for fluids, six months for test markers).
• Never leave bottles or markers uncapped! Evaporation, water vapor, and airborne contaminants all affect dyne level, and can invalidate them long before expiration.
• Printers, coaters, and laminators should pull samples and perform the test as soon before the print station (or similar) as possible. It may be worthwhile to dyne test the roll before it goes on the machine, and compare these results to material which has run through the web handling process to the print station. This will indicate the treat loss attributable to process roll contact and web handling.
• Polyester film which reads consistently below 42 dynes/cm is almost certainly "print primed." This chemical process actually decreases the surface energy a bit, but makes the surface attractive to a far broader range of compounds used in inks and coatings.
• Cleaning systems can be monitored by the dyne test. The surface energy of metals is much higher than that of surface contaminants; thus, the higher the dyne level, the cleaner the part is. Always use test fluids to measure cleanliness — even our spring-loaded valve tip markers will eventually be overwhelmed by repeated exposure to contamination.
• The presence of mold release on many plastic parts can be similarly identified. Again, test fluids are indicated for this application.
If you have a valuable tip you'd like to share, we'd love to hear from you. All tips will be considered for publication on the site.
USING THE DYNE TEST TO EVALUATE THE CLEANLINESS OF METALS
This report details a method of using surface tension test fluids, formulated in accord with ASTM Std. D2578(1), to evaluate the cleanliness of metal surfaces. To determine the wettability of metal surfaces (Because contaminants are of lower surface energy than the underlying metal surface, the wettability of the surface, as measured in dynes/cm, is a good proxy for the degree of cleanliness of the material.
To ensure replicability of this test, sample selection and handling and test technique must be standardized. Ambient, sample, and test solution temperatures, as well as relative humidity, must all be controlled: For industrial testing, we recommend testing within a maximum range of 15°C (59°F) and 30°C (86°F), and 35% to 70% relative humidity. Ideally, the range would be 20°C to 25°C and 40% to 60% RH. Temperature control is most critical, as the relationships between temperature and surface energy of different metals vary considerably: For example, one study shows that the surface energy of chrome plated steel remains essentially unchanged (42 dynes/cm) at 40°C compared to 160°C. By contrast, aluminum foil drops from 45 dynes/cm to 38 dynes/cm over the same temperature change.
Inspection methodology is also critical, and the following points need to be considered:
• Cleanliness testing of metals should always be done with bottled test solutions, applied with cotton applicator swabs. We recommend dropper bottles, which can apply a standardized amount of test fluid to each swab. The smallest amount of test solution that can practically be applied is ideal: surface energy is a two-dimensional property. Applying too thick a film of test fluid can cause gravitational spreading, which will result in higher dyne level readings.
• Do not touch or in any way contaminate the surface to be tested.
• Do not use contaminated test fluid; dispose of it immediately and use a fresh batch.
• Dyne pens should not be used for cleanliness testing: Even AALKEMY DYNE TEST Marker Pens will end up with contaminated tips and produce errant results if used on oily or silicone-contaminated surfaces.
• A fresh, unused swab must be used for each application of test fluid.
• Each test must be performed on a previously untested part of the sample.
• The test should always start from a low dyne level — one that you expect should fully wet the surface. As long as that dyne solution stays wetted out, and does not shrink in and form beads within two seconds, the test should be repeated at the next higher dyne level (if the test fluid beads immediately, drop down at least four dynes/cm, and start the test over).
• Always keep bottles securely capped when not in use. Evaporation of the two test fluid constituents will not be equal the Liquid will evaporate preferentially, increasing or decreasing the surface tension of the test fluid.
• If the part that is tested must be retained for subsequent processing (as in testing expensive aerospace components, e.g.), the test area should be cleaned with isopropyl alcohol immediately, then sent back through the cleaning process for a second pass. For large-scale test programs, one master trainer should directly train all testers to ensure uniformity of technique.
Frequently Asked Questions for Surface Energy / Tension Checking corona dyne pens – Liquid
Why Measure Surface Energy?
In general, the ability of a substrate to anchor inks, coatings, or adhesives is directly related to its surface energy. If the substrate surface energy does not significantly exceed the surface tension of the fluid which is to cover it, wetting will be impeded and a poor bond will result. Therefore, assessing surface energy before printing, coating or laminating is attempted is an important part of many industries' manufacturing processes.
It is important to note that while surface energy is critically important to many converting operations, it is not the sole determinant of product suitability. Factors such as the surface topography, coating rheology and chemical incompatibility must also be considered.
What Is a Dyne?
The unit of measurement of Surface Energy is Dyne/cm² this can also be expressed in mN/m. Dyne = Unit of force equal to the force that imparts an acceleration of 1cm/sec/sec to a mass of 1 gram.
1 Dyne = 0.00001 Newtons.
What materials can Dyne Pens be used on?
Dyne test marker pens perform well on most non-absorbent materials. It is critical that the test fluid does not alter the surface properties of the substrate. For example, if the test fluid permeates a fibre substrate (e.g. paper) and causes swelling, results will indicate unrealistically easy wetting. A chemical reaction between the test fluid and the substrate invalidates results altogether.
What Is a Dyne Test?
Dyne tests measure surface wettability or adhesion. Dyne is used as a unit of force in the milli-newton per meter system of units. When using dyne tests you are capable of measuring surface tension in the units millinewtons per meter or dyne per centimeter.
How To Use Dyne Pens?
Four Easy Steps for Measurement
1. Choose a DYNE TEST marker pen of a dyne level you believe is slightly lower than that of the test sample.
2. Press the applicator tip firmly down on subject material until the tip is saturated with ink.
3. Use a light touch to draw the pen across the test sample in two or three parallel passes. Disregard the first pass to flush any contamination from the tip, and to ensure that the test fluid layer is thin enough for accurate measurement, evaluate only the last pass.
4. If the last ink swath remains wetted out on the test sample for three seconds or more, repeat steps 2 and 3 with the next higher dyne level marker. If the last ink swath beads up, tears apart, or shrinks into a thin line within one second or less, repeat steps 2 and 3 with the next lower dyne level marker. If the ink swath holds for one to three seconds before losing its integrity, the dyne level of the marker closely matches that of the sample .
IMPORTANT SAFETY NOTICE:
The constituents of these solutions are classified as hazardous materials. Avoid contact with skin. Perform tests with adequate ventilation. Pregnant women should not perform this test. Avoid contact with eyes; safety goggles are recommended. For further information, refer to the product MSDS or call Bhumi Chem (India) at
022-28937494 or mail us on Bhavya@bhumichem.com