The relationship between the effectiveness of lash adhesive and humidity is a burning topic in the industry, and while a lot of information is available, some of it is quite misleading. Understanding this relationship is very important for your business, and the glue that you use is possibly the most important aspect of your technique, as low quality adhesive can not only make the lash extensions short-lived, it can also cause allergic reactions and a lot of discomfort for both you and your client.
Knowing Your Chemistry
The glue that we use when applying lash extensions is medical grade cyanoacrylate adhesive. Cyanoacrylate is a component of a lot of glues on the market, and is known for having a strong bond and being long lasting. We refer to cyanoacrylate-based glues as “super glue”, with the nickname referring to its incredible bonding power. Lash adhesive is medical grade, which means that although the base is the same, coming from the same family of adhesives, we’re using a safer, lower toxicity version, with longer polymer chains making them have minimal toxicity as they bond. The adhesive becomes stable as it goes from liquid to solid form – it cures upon contact with water vapor in the air. The presence of water vapor is what we refer to when we talk about air humidity.
Understanding the chemical composition of lash adhesives is key, especially when it comes to components like formaldehyde. It's a common misconception that some adhesives contain added formaldehyde. In reality, formaldehyde is a byproduct of the cyanoacrylate curing process. The amount generated is typically very low, often in parts per million, and sometimes it's even undetectable, which is significantly less than in many daily-use products. For context, everyday items like school glue and baby wash contain slightly higher formaldehyde levels and are still safe to use. Additionally, it's worth noting that formaldehyde naturally occurs in the human body and doesn't accumulate in the environment, thanks to its rapid breakdown by sunlight or bacteria. While the word 'formaldehyde' may raise concerns, the exposure levels from lash adhesives are minimal, especially when compared to other common sources.
This is not the only company-perpetuated myth out there. Another is the misconception regarding air humidity and how it is discussed in the lash community. Cyanoacrylate is sensitive to relative humidity, not absolute humidity, and it’s crucial to know the difference. Absolute humidity, also known as actual humidity, is the measure of water vapor in the air regardless of temperature. Relative humidity is the measure of water vapor in the air relative to the temperature. These are very different things and it’s crucial to make sure you’re looking at the correct metric when comparing your actual environment conditions to your glues specification. The optimal relative humidity for most lash adhesives to work in is between 50% and 70%.
How Does Humidity Affect the Adhesive?
Relative humidity is what affects the process of adhesive curing. When the cyanoacrylate comes in contact with moisture, or water vapor in the air, a chemical reaction starts to polymerize the adhesive, which causes the adhesive to solidify. If the air humidity in your work space is too high, shock curing can take place. Shock curing is the speedy polymerization process. While having the glue solidify faster seems tempting, this is a bad solution as the bond which is formed with the natural lash is much weaker. What’s more, the adhesive will be rigid and isn’t able to move flexibly following the natural movements of the lashes, which leaves the client with a feeling of stiffness and discomfort, causes damage, and makes the lashes break off quicker and more easily. The adhesive will always dry quickly, almost instantly, but that is just the outer coat – the inside of the adhesive will take between 24-48 hours to dry, and this slow process is what gives the adhesive bond strength and flexibility over shock curing.
Humidity being too low is also an issue, as there could potentially be too little water vapor in the air to get the adhesive to cure properly in the first place. This leaves your client with poor retention, and ultimately similar results as with humidity being too high: rigid, stiff, easily breakable glue.
All the Gadgets: Are They Worth It?
In the lash industry, there's a variety of tools marketed to help manage humidity levels. It's important to discern which devices will truly benefit your practice. While not every gadget will be essential, the right tools can be invaluable in ensuring the durability and quality of lash extensions.
Therma-hygrometer: Commonly used in salons, a standard hygrometer is an essential tool that measures the relative humidity of your workspace, providing the precise data required for optimal lash adhesive curing. These user-friendly devices offer direct readings of relative humidity, allowing technicians to maintain the perfect moisture balance without any complex calculations.
Nanomisters and Nebulizers: These two devices are meant to instigate shock curing by creating a fine mist that speeds up the polymerizing of the adhesive.. Although these devices may seem an attractive tool to use to speed up the lashing process, as discussed previously, when the lash adhesive dries extremely fast, this can cause issues with the flexibility of the bond and ultimately the retention. However, many lash artists do still enjoy using them and your results may vary, so just beware!
Dehumidifiers: The opposite of nanomisters and nebulizers, dehumidifiers are devices which reduce water vapor in the air, lowering air humidity. However having a too low humidity environment decreases the performance of the glue, making it dry slower and ultimately weakening the bond. Before deciding to use either of these devices, make sure that you understand your environment and whether any of these devices are actually necessary.
Understanding Humidity's Crucial Role in Lash Adhesion
The retention and effectiveness of lash adhesive are significantly influenced by relative humidity, which is the amount of moisture in the air relative to its temperature capacity. The ideal range of relative humidity for effective curing of lash adhesives is crucial; too high or too low can lead to poor results. For lash technicians, precise monitoring of this environmental factor is essential. Tools like hygrometers are indispensable for providing accurate humidity readings, allowing for adjustments to achieve optimal adhesive performance.
Beyond just climate conditions, the success of lash extensions also hinges on the quality of the adhesive and the application technique. A high-grade cyanoacrylate adhesive, applied correctly, is vital for durable and long-lasting lash extensions.
Conclusion: Harmonizing Technique, Tools, and Environment
Mastering lash extension application is a balance of art and science, demanding precision in both technique and environmental control. Understanding and maintaining the correct relative humidity levels is a fundamental part of this process, ensuring the adhesive cures properly for lasting results. By combining skilled application with the right tools and environment, lash technicians can provide clients with beautiful, long-lasting extensions. This approach elevates the standard of service, ensuring client satisfaction with every application.