Aerosols: to create the future, we must understand the past

Published: October 30, 2017

Today there are over 200 different types of aerosols products and around 200 UK brands that use them. Patrick Heskins, Chief Executive at the British Aerosol Manufacturer’s Association (BAMA) highlights some of the most significant developments that have shaped the aerosol form as we know it today.

The progression of the aerosol can is as interesting to historians as it is to the multitude of sectors it supplies. Although the early life of the aerosol began towards the end of the industrial revolution it is Erik Rotheim, a Norwegian chemical engineer who is credited with the invention in 1929 after he recognised the need to apply wax to his skis more evenly.

Rothheim’s thick walled brass prototype was not the first venture into liquid dispensing functionality. In 1825 England’s Charles Plinth created the Regency Portable Water Fountain which used pressure to dispense soda water, controlled by a stopcock. Soon after, this design was replaced by a siphon champenois, a hollow corkscrew which allowed for pressurised drinks to be dispensed without the use of a cork.

12 years later, the vase siphoide which utilizes a valve operated spring came to the fore but was quickly replaced by aerated water syphon on a similar principle. Both ideas contributing to the soda water syphon as we know it now.

The ‘Bug Bomb’

Say the words ‘World War Two inventions’ and the most common association is Sir Alexander Fleming’s penicillin because, despite the fact that the antibiotic was first discovered in 1928, it rose to prominence during the war to address severe medical infections, with hundreds of billions of units produced every month. Similarly, cyanoacrylates (or super glue, as it is more commonly known) was discovered by Dr Harry Coover in 1942 when research into clear plastic gun sights started.

However, the rise of aerosols during the Second World War is perhaps a lesser known fact. In the Pacific Rim region where the Philippines, Singapore, Australia and New Zealand are situated, insect borne diseases were killing men at a rapid rate.

To tackle this, Research Chemist, LD Goodhue and WN Sullivan created an insecticide spray in 1942, based on Goodhue’s original invention in 1935 which used liquefied halogenated hydrocarbons. Named the ‘bug bomb’ to reflect the shape of the can, soldiers used 40 million aerosol ‘bombs’ to fight off mosquitos carrying malaria in the region.

This prompted interest from the public following the war and manufacturers started to see the potential as beer cans were modified and plastic valves replaced the copper ones originally used. Initially only used for insecticides, shaving foam, paint, lubricants and perfume manufacturers then started to see the wider potential of the aerosol format for their customers. Today, the personal care sector accounts for the lion’s share of the aerosol market with significant increases in all categories from 2006 to 2016.

Reformulating hydrocarbons

As the largest manufacturer of aerosol products in the UK, the personal care sector was at the centre of the voluntary decision to end the use of CFCs in 1989, after the effects on the ozone layer were understood. The conversion to the use of hydrocarbons ultimately resulted in extensive reformulation throughout the industry.

Hydrocarbons are made up of n-butane, isobutene (methyl propane) and propane to create the desired pressure. Some products use dimethyl ether (DME) which has a higher pressure and solvency and gives a drier spray.

The reformulation of hydrocarbons is a fastidious process which requires the valve to be configured to ensure flammability risk is as low as it can be. Compressed gases such as nitrogen and carbon dioxide are used in some aerosol products, usually in the house hold sector but there is a limit on the proportion that can be used, due to the fact that compressed gases do not turn into liquid and therefore there is not enough to assist with the break-up of the spray.

Pressure inside the aerosol can reduces as the contents are used. This means that the right formulation is critical for the consumer to be able to use all of the product. The correct formulation will also ensure the spray pattern, particle size, flammability and force of spray is well suited to the product.

What now?

Having successfully replaced CFCs with hydrocarbons and addressed the issues relating to ozone layer depletion, one of the key challenges today for aerosols and indeed, all packaging materials, lies with recycling and waste reduction targets. Out of the 70% of the population who buy and use aerosols, there are around73 % who recycle these, according to the result of a GFK NOP survey conducted by BAMA.

Leading the way to improving the green credentials of aerosols are the continued high levels of innovation that echo the creative inventions of the past and build on what we can predict about the future where a new, highly developed digital era awaits us.


Copyright © 2017 Mack Brooks Speciality Publishing.