Zotefoams plc is recognised as the world leader in advanced technical foams. The company is the direct descendant of Onazote Limited, the company that was founded in 1921 and commercialised the world’s first hard and soft expanded rubber.
Thomas Edison
American inventor and mentor of Charles Marshall
Founder of Onazote Limited, Charles Marshall, born in Birmingham in 1860
Inspired by the work of three Austrian brothers, Hans, Fritz, and Herman Pfleumer, who had conceived the original concept of filling tyres with some form of expanded lightweight material, rather than air, Charles Marshall, patented a process to manufacture expanded rubbers of all kinds – hard and soft. In 1921 he founded Onazote Limited the forerunner of Zotefoams plc…
Fritz Pfleumer holding a section of expanded rubber material used for tyre filling in 1910
Hans Pfleumer
Herman Pfleumer
500mm autoclave with improved lid, Breslau 1917
120mm autoclave at St. Denis, Paris,1912
The search for optimal materials
Although the concept of the puncture-proof automotive tyre was ultimately unsuccessful, experimentation highlighted the potential of this novel material for a multitude of applications …
Marshall registered the trademark Onazote in Great Britain and the USA; the name is believed to derive from the words ebonite –hardened rubber – and azote, the French word for nitrogen.
1925 The name of the company was changed to the Expanded Rubber Company Limited, with Onazote remaining in use as a product name for decades to follow.
This year also saw the first recorded use of Onazote for refrigeration; the letter is from Charles Marshall to T Wall and Sons, who were developing their ice cream business Today, Zotefoams’ T-FIT technical insulation is used extensively in ice cream manufacturing businesses globally to reduce condensation.
1927 The company moves from its original north London home to the 50,000sq.ft Palace of Arts at Wembley, originally constructed for the 1924-25 British Empire Exhibition.
The Palace of Arts
1929. British Industries Fair catalogue.
1925 – Onazote was introduced to the refrigeration industry, the letter is from C L Marshall to T Wall and Sons Limited, who still use this thermal insulation material.
Success beckons
Moving in the right direction
Early picture of Mitcham Road, Croydon
In 1935 the company moved to a former cable works in Mitcham Road, Croydon. Zotefoams headquarters and main manufacturing site are still located.
With commercial success still proving elusive, ownership of the company passed to the St Helens Cable and Rubber Company in 1938. This marked a turning point, with a new Managing Director, Henry Shelmerdine, entrusted with reorganising and equipping the business.
Within a year, production was steady at half a ton (over 500kg) per week of Onazote and Rubazote – hard and soft expanded rubber. Insulation in food industry applications and seals and gaskets were key markets.
Prosperity followed, and the new management team was able to convince government departments that the company and its materials were to be relied upon.
Henry Neal Shelmerdine was put in charge of the company re-organisation in 1938
Innovation and
expansion in support of the nation
Wartime saw a rapid increase in demand for Onazote and Rubazote, primarily in marine buoyancy and aviation applications.
Shelmerdine’s drive and initiative was fully tested in the service of the nation. New processes were developed for making a special soft rubber – Aerozote – used for self-sealing aircraft fuel tanks.
New factories were opened in Slough and Dundee, to manufacture defence products such as booms and trailing cables, insulation for military containers and, most intriguingly, superstructures for midget submarines.
With global supply chains impacted by the conflict, the company’s most vital raw material, natural rubber, was in desperately short supply.
During the 1940s, the Expanded Rubber Company produced 1.5 million m2 of Aerozote, used to line self-sealing fuel tanks.
Opening of Expanded Rubber Company Dundee factory, by the late Sir Stafford Cripps 1945.
That challenge was a driver for innovation and, in hindsight, an early indicator of the search for optimal materials that is the hallmark of modern-day Zotefoams.
Developments included Formvar, an expanded vinyl with great impact strength and FUF, expanded urea-formaldehyde resin. This looked like snow and was used to create the blizzard effects in the famous 1948 adventure film Scott of the Antarctic – perhaps the starting point for Zotefoams’ long association with the creative industries.
Granules of FUF driven by studio wind machines provided the realistic blizzard effects
A world of applications
In the early 1950s the Expanded Rubber Company was the largest company in the world completely engaged in the manufacture of expanded materials.
Zotefoams in 1950
The Sales Department was expanded, new equipment and a new laboratory installed and agents appointed in all major industrial nations.
With a secure supply of rubber once again available, Onazote and Rubazote were once again the main products but growth was also supported by innovation, with a product range buoyed by new materials. A sponge rubber – Zote – was promoted alongside a microcellular shoe soling material, while Rubacurl, a complementary product to Rubazote, bonded lightweight latex with hair to give extra strength in product protection applications.
Vickers Valiant with nose radome made from Onazote
Onazote lifejacket approved by the Ministry of Transport
Rubacurl (lightweight latex-bonded curled hair) used to pack a self priming pump.
The Great White Whale used in the 1956 film ‘Moby Dick’ was made from an ultralight -density sheet of Rubazote over a wooden frame.
Lifeboat fitted with Onazote solid buoyancy unit
Introducing Plastazote® and Evazote®
In 1962, Plastazote® was launched. This now-iconic brand, the foundation of the AZOTE® polyolefin foams, is produced from polyethylene and used in a vast range of applications in sectors including automotive, aviation, building and construction, industrial, marine, medical, military, product protection and sports and leisure.
In its infancy, Plastazote was in great demand for medical and healthcare applications, such as neck and body splints, orthotics and limb supports. This was thanks to the purity of the materials, derived from the unique three stage manufacturing process, which makes them ideal for skin contact applications. Plastazote remains the most cited thermoplastic foam in medical literature.
An aerial view of the Croydon premises
1968 saw the introduction of Evazote® EVA copolymer foam, a further world-class product, boasting additional toughness and resilience.
Plastazote was specified by famous brands such as the Jensen Company, which used the material for impact and energy absorption in its revered Interceptor. The model shown here is the Mk II, manufactured between 1969 and 1971.
Jensen specified Plastazote for its impact/energy absorption
Rubazote
was finally discontinued after nearly 40 years of production
New ownership and a final farewell to rubber products
The success of Plastazote and Evazote, together with difficult trading conditions for rubber, led to the decision in 1974 to cease production of rubber materials. The expanded polystyrene business was also sold, enabling BXL to focus fully on the evident potential of Plastazote and Evazote.
By the end of the 1970s, demand for these materials across automotive, civil engineering, marine, aviation, commercial packaging and insulation as well as healthcare applications resulted in four-shift working. The company was acquired by British Petroleum (BP) in 1978 and remained part of the Chemicals division for the next 15 years. This was a period of significant investment in modern production machinery to meet increasing demand and broaden the product range. Plastazote LD24, at the time the lightest foam of its type in the world, was launched in 1984, opening up many new applications.
When Rubazote was finally discontinued, it had been in production for nearly 40 years.
Royal recognition and global growth
In 1981, Plastazote achieved royal recognition when it received the Prince Philip Award for polymers in the service of mankind. The Award was presented by its namesake, a champion of British technology and industry.
The next decade saw continuing growth and success on the global stage, firmly establishing Plastazote and Evazote as the world’s leading technical foam brands.
In 1981 Plastazote was singled out for special recognition when the Duke of Edinburgh presented the company with a gold medal in recognition of the contribution made by Plastazote foam in the service of mankind.
A new era and the birth of Zotefoams plc
In 1992 a management buyout established Zotefoams Limited; this was followed by a flotation on the London Stock Exchange (ZTF:LON) in 1995, which gave birth to Zotefoams plc.
International growth continued following the flotation, with the establishment of a North American sales subsidiary, Zotefoams Inc, to meet rapidly growing demand with local service.
The High-Performance decade
As the new millennium dawned, opportunities and optimism were abundant – but on the night of October 22, 2000, a fire at the Mitcham Road site caused damage running into millions of pounds and destroyed a third of the factory.
No cause was ever identified but more importantly, as the company rebuilt, safety was, and remains to this day, the primary consideration.
In the aftermath of the fire, the management team, led then as now by Group CEO David Stirling, reassessed the prospects for the business. The development of the ZOTEK® High-Performance Products (HPP) portfolio traces its origins back to that time, with the decision to leverage the capabilities of the three stage process for new, advanced materials. These unique materials would meet demanding regulatory and application requirements, using Zotefoams’ technology and know-how.
In 2001, Zotefoams Inc moved into a purpose-built facility in Kentucky, strategically located for ease of access to major manufacturing hubs in the USA.
Rebuilding in the UK too, the company completed new headquarters, manufacturing and R&D buildings.
ZOTEK F 30, produced from PVDF polymer and the first commercial grade in the HPP family, was launched in 2004, followed in 2008 by the first ZOTEK N nylon foam.
2008 MuCell® microcellular technology
In 2008 Zotefoams established a stake in Massachusetts-based MuCell Extrusion Technology LLC, a joint venture formed to exploit and license a proprietary microcellular foaming technology for extrusion processes. Four years later and as MuCell Extrusion LLC (MEL), the company became a wholly owned Zotefoams subsidiary. Today, MEL is the powerhouse behind Zotefoams’ groundbreaking ReZorce® mono-material barrier packaging range.
A world leader in optimal material solutions
The past decade has been one of accelerating change and growth for Zotefoams.
The HPP range has continued to develop, to great acclaim. ZOTEK F is the lightweight material of choice for aircraft interiors, its versatility lending itself to many applications, in the cabin and behind the panels. The range includes NASA-approved grades, used across all current space programmes.
The ZOTEK N family now incorporates a lighter grade and in 2012, ZOTEK PEBA, a foamed Polyether block amide designed for the footwear industry, was introduced. The product is now famously the basis of Zotefoams’ exclusive and record-breaking partnership with Nike.
2015 T-FIT® unique insulation technology
Alongside the development of outstanding new products, Zotefoams has increased its global presence through new subsidiaries and joint venture partnerships. A 2015 joint venture in China to manufacture and sell the T-FIT insulation range is now wholly owned and, as Zotefoams T-FIT Material Technology (Kunshan) Co Ltd, enjoying considerable success.
In Asia and Australasia, AZOTE polyolefin foams are promoted through a joint venture company based in Hong Kong, bringing the benefits of these exceptional materials to manufacturers in the region and notably the automotive industry.
In 2018, Zotefoams Inc extended its facility and added extrusion and a high-pressure (HP) autoclave to complement the existing HTLP capabilities at its site, making the USA manufacture and supply of many AZOTE grades a reality.
A second HP autoclave came onstream in 2020.
In 2019, the UK manufacturing site increased capacity for expansion of materials with a new factory housing two large high-temperature low-pressure (HTLP) autoclaves for the expansion of nitrogen-saturated slabs and in the same year, Zotefoams established a T-FIT sales and service centre in Ahmedabad, India to support the growing food and pharmaceutical sectors in the region.
In February 2021 the company began operations at a third foam manufacturing site. Located in Brzeg, south west Poland, the site produces the most popular AZOTE grades for customers in Continental Europe.
World-class lightweight crosslinked polyolefin foams
With the capacity investments in the UK, the USA and Poland, Zotefoams has increased its global block foam manufacturing capacity by 60% compared to the position at the end of 2017.
Zotefoams is also investing in ReZorce ahead of its commercial launch, anticipated by early 2023. A new pilot facility in Massachusetts housing an extrusion line and downstream filling, packing and validation facilities will welcome its first customers soon
Today Zotefoams continues to develop and produce world-class foam products, while expanding its reach as an international organisation.
