In July 1980, British engineer J. Brian Blackwell filed a patent based on a simple observation, that the way foam rises can be changed by controlling the pressure around it.
Until then, flexible polyurethane foam was largely produced at normal atmospheric pressure. Its density, firmness and cellular structure depended mainly on the chemical formulation and the conditions on the factory floor. Variable Pressure Foaming, or VPF, introduced another means of control. Foam could now rise inside a sealed chamber where pressure was adjusted during production.
This gave manufacturers more freedom to decide what kind of foam they wanted to make. We had kept VPF in our view and long-term plans from the very start. It fits our strategic and environmental goals.
From a start to systems scale
Over time, VPF found its place in large foam-manufacturing operations across the world. Its environmental advantages attracted early attention because it could eliminate methylene chloride as an auxiliary blowing agent.
For Sheela Foam, that was only part of its relevance. SFL saw VPF as a way to improve the foam itself.
A foam manufacturer is constantly working with properties that pull in different directions. A soft foam must still offer support. A lightweight foam may need to carry substantial loads. A material designed for repeated use must retain its shape and performance over time. Changing the chemical recipe can achieve some of this. Controlling pressure adds another useful tool.
This matters because foam does far more than most people see.
Not all foam is created equal
It is inside the mattress on which someone sleeps, the seat of a car, a hospital support surface and the furniture used every day. In each case, the foam is doing a different job. The required balance of comfort, airflow, resilience and durability changes with the application.
VPF allows these properties to be controlled more precisely. Production inside a sealed chamber also reduces the effect of changing atmospheric conditions, helping manufacturers produce foam more consistently across batches.
For a company operating across consumer, furniture and technical markets, that consistency has practical value. A successful foam formulation must perform in the laboratory, on a full production line and in the finished product. It must continue doing so when production volumes increase.
Early adoption
Sheela Foam’s experience with VPF has been built over many years and across several countries.
The group acquired Joyce Foam in Australia in 2005. Joyce introduced VPF at its operation in 2010 and now uses the process to manufacture more than 60 foam grades for bedding, furniture, medical and industrial applications. This gave the group operating experience with pressure-controlled foaming in a mature international market.
In India, SFL developed Vertical Variable Pressure Foaming (VVPF). In this process, foam rises continuously inside a vertical chamber to form a round block. The geometry makes it particularly useful for producing long, continuous sheets for quilting and related applications. SFL’s work in the field was recognised by PU Tech in 2017 with an award for innovative technology in Vertical VPF.
Another established centre of expertise joined the group in 2019 with the acquisition of Interplasp in Spain. Interplasp had begun developing its VPF capability in 2007, installed the equipment in 2010 and started production the following year. It now manufactures exclusively through VPF.
Today, Sheela Foam has VPF manufacturing experience across India, Australia and Spain. These operations serve different customers and product categories, but they share a common belief: better control over manufacturing creates more room for better product development.
The Indian chapter
The most ambitious expression of this belief is in Jabalpur, Madhya Pradesh.
Spread across 11.7 hectares, the greenfield facility was planned around fully VPF-based foam production. The decision was unusual in South Asia, where conventional slabstock manufacturing remained the more established route.
The plant also had a clear commercial purpose.
SFL’s “Mattress for Every Indian” strategy recognised that a large part of the country continued to sleep on cotton-filled mattresses, durries, EPE foam and other traditional surfaces. Reaching this market required more than an advertising campaign. It required a manufacturing system capable of producing dependable polyurethane foam at much larger volumes and at a cost suitable for a wider section of consumers.
Our investment in this fully VPF plant is integrated—we expect higher production capacity and an estimated manufacturing-cost advantage of 10 to 15 per cent.
This made VPF part of a market-development strategy. The aim was to use manufacturing technology to bring engineered foam products to people who had previously remained outside the organised mattress market.
The facility has continued to grow. During FY2024–25.
The plant’s central location also matters. Jabalpur provides access to markets across India while giving SFL a dedicated base for refining formulations, improving production economics and developing foam for new applications.
Advantage Earth
VPF eliminates the need for methylene chloride in the foaming process. Because production takes place inside an enclosed chamber, trace volatile compounds can be captured and passed through activated-carbon systems rather than being released into the factory environment.
These are important gains. They sit within a broader manufacturing argument.
SFL believes future growth in foam will come from understanding performance more precisely and producing it reliably at scale. Customers are becoming more aware of what lies inside a mattress or piece of furniture. Industrial buyers already purchase against technical specifications. Both expect greater consistency from the material.
The history of VPF within Sheela Foam reflects that view. Joyce brought international production experience. SFL developed Vertical VPF in India. Interplasp added a European operation dedicated entirely to the process. Jabalpur has now taken the technology into a larger and more ambitious phase with its horizontal VPF machine.
The second VPF line at Jabalpur is running. What matters now is the foam that comes from it, the people it reaches and the new uses that can be developed from the capability already in place.