Airless packaging has become a necessity for sensitive formulations, with particular focus on the skincare, cosmetic, and personal healthcare industries. We’ve answered some common questions about airless packaging many times with our clients, and we’ve decided to share our expertise with the world via this article! So... What is airless dispensing?
What exactly is airless packaging?
Typically, an airless package is a dispensing system that uses a single-direction pump. This means it does not allow air from the atmosphere back into the container like a standard pump. The displaced liquid needs to be replaced in some other way such as a rising piston or collapsing bag or tube.
The actuator is used to pump product out of the reservoir which creates a vacuum and therefore a lower pressure. Once the pressure in the reservoir has decreased enough, the product is dispensed through the actuator. This ensures a much more accurate dosage from the dispenser after the pump has been primed.
To understand how airless packaging works it is helpful to think about it in terms of difference to a conventional pump. In a conventional pump a vacuum is created in the chamber of the pump engine which forces the product out, and when the pump is released atmospheric air is allowed back into the bottle or container to balance the pressure. The difference with airless packaging is that no air is allowed back into the bottle or container and therefore the pressure difference has to be compensated for by the size of the reservoir reducing – hence the moving parts in the airless container.
There are essentially two types of airless bottles, one of which features a rising internal piston and the other a collapsing inner skin or bag in the bottle. The rising piston is certainly the most common and this works when the vacuum suction created by the product being dispensed causes the piston to rise up inside the pump reservoir. The collapsing bag version features high precision technology where a very thin plastic liner or co-extruded part of the container will collapse as the product is dispensed to have the same effect.
Most airless bottles & pumps are distinct from other conventional pumps by absence of a dip tube going to the bottom of the bottle. At first sight this can look like a fault but since the product is dispensed from the top of the bottle a dip-tube is not required.
What is priming?
Priming a pump is expelling all air from the pump mechanism, or in the case of an airless pack, from the top of the airless container to ensure it is dispensing product only, and therefore operating correctly. Depending on the product, priming can take 5, 30, or more “strokes” (pumps) to create the vacuum necessary to dispense the product.
If the pump is removed from the airless bottle, when re-connected, it then needs to be primed again as air will have entered the reservoir and negated the vacuum. It is always advisable when filling an airless pack to prime it immediately after filling to eliminate any air in contact with the product. This ensures best integrity of product for the consumer as well as making it user-ready.
With many formulations being increasingly designed to treat specific problems, be it skincare, haircare, cosmetic, or otherwise, the integrity of the product is paramount. Even the small amount of impurities or bacteria in the air can affect a product, often causing emulsions to break down and reducing the shelf life of a product.
Sometimes, large amounts of preservatives are included in formulations to try to counter-act this effect. With airless packaging, the product does not come into contact with the air until it is dispensed and as a result, the product requires little or no preservative and is less susceptible to degradation and discolouration.The complexity of today’s formulae means airless dispensers are essential to protect sensitive and active ingredients from degrading.
Easy to use
Generally, airless packs will dispense the product effectively regardless of the rotation or angle of the pack! Since they dispense from the top and do not require a dip tube, most can be dispensed upside down or at an angle. Single-handed operation is also an advantage compared to jars and conventional bottles.
No internal pressure
The packaging does not require additional internal pressure to push the product out. This means airless packaging isn’t shipped under pressure and offers a valuable safety advantage compared to aerosol packs.
With airless packs being designed this way they do not require a propellant, unlike aerosol dispensers which generally rely on the use of harmful propellants which are harmful to the environment and can cause asthma and allergic reactions. Some airless ranges can be cleaned and refilled. Both points mean it is much better for the environment.
Every little helps in reducing everyone’s carbon footprint!
Why can’t I get a glass airless container?
Glass is a natural product. As a result, there are much larger tolerances in production. For the airless system to work, the walls of the bottle need to be completely parallel with each other to allow the piston base to move smoothly and as a result, effectively dispense the product. Glass also tends to ripple which means the uneven surface would cause the piston base not to seal correctly, and therefore the pressure could leak, resulting in an overall defective product.
From a manufacturing point of view, if it were possible to get consistently smooth walls with a natural product such as glass, how would we get the piston within the glass bottle?
There is the possibility of having the bag-in-bottle product, however the plastic bag within the bottle would negate the benefits of glass!
At Richmond we believe that high quality formulations need the best quality of container. Our range of airless dispensers fit a variety of requirements. As always, please contact us to discuss your project or if you have any further questions!