Mattresses & cushions

The most popular types of foam

Polyurethane foams

Flexible polyurethane foams are the material used to make most mattresses and fillings. They are known for their lightweight construction, durability and elasticity.

Memory foam

Currently the best choice for pressure reduction in mattresses. Memory foam is known for its deep body contouring and pressure-reducing properties. It reacts to body heat, softening and moulding to the shape of the body.

Latex foams

This type of foam is based on latex. It is characterised by high resilience and elasticity. Latex foam maintains constant support and does not soften, ensuring high comfort of use.

Highly elastic foams

This is one of the types of polyurethane foams. Their main feature is elasticity and resistance to deformation.

Thermoelastic foams

It adapts very well to the shape of the body, e.g. in mattresses. This type of foam reacts to body heat, ensuring thermal comfort.

Raw material for foam production – the basis of quality

Polyurethane foams are currently the most common and versatile choice in the production of, among other things, modern mattresses and pillows. Each PUR foam is the result of a carefully balanced chemical reaction between polyols and isocyanates. The mutual proportions of these components are of key importance. The amount of isocyanate used directly determines the hardness of the final polymer, while its softness and elasticity depend mainly on the type of polyol used.

Polyols are organic compounds with hydroxyl (-OH) groups built into their structure. The right choice of the optimal type of polyol – most often polyether or polyester – is essential to achieve the desired elasticity, resilience and chemical resistance of the foam. Polyether polyols, thanks to their high elasticity and moisture resistance, are widely used in the production of flexible foams. Their excellent physical and chemical properties make them the preferred choice in applications such as furniture and automotive. Polyester polyols, on the other hand, although less commonly used in soft fillings, are chosen wherever strength, mechanical resistance and chemical stability are key. Due to their specific properties, they are mainly used in the production of rigid foams and technical foams.

Isocyanates are the second main component in the production of polyurethane foam, reacting with polyols in a process called polymerisation. The most commonly used isocyanates are toluene diisocyanate (TDI) and diphenylmethane diisocyanate (MDI). TDI is a liquid isocyanate widely used in the production of flexible (soft) polyurethane foams. It is characterised by a relatively low molecular weight and high reactivity. High-density PUR foams based on TDI are typically characterised by good elasticity and comfort, making them suitable for applications such as furniture cushions. MDI, on the other hand, is an isocyanate that exists in a solid or semi-solid form at room temperature. High-density polyurethane foams based on MDI offer a number of advantages over TDI-based foams. They are characterised by better dimensional stability and higher load-bearing capacity. These properties make MDI the preferred choice for automotive applications, where high-density polyurethane foam is used to manufacture seat cushions and headrests.

The role of additives in foam formation

Additives play a key role in controlling the reaction rate and determining the density, hardness and mechanical properties of the foam, ensuring consistent performance in the intended application.

Flame retardants

Flame retardants are added to improve the fire resistance of high-density polyurethane foam. They work by suppressing the ignition process or slowing down the spread of fire. Common flame retardants include halogen compounds, phosphorus-based compounds and inorganic fillers. In applications where fire safety is important, such as furniture and car interiors, the addition of flame retardants is essential.

Catalysts

These play a key role in the polyurethane polymerisation process. They accelerate the reaction between polyols and isocyanates, ensuring the correct foam formation rate. Two main types of catalysts are used in the production of high-density polyurethane foam: amine catalysts and tin catalysts.

Foaming agents

They are responsible for creating the cellular structure of the foam by producing gas bubbles during the reaction.

Surfactants

These are added to the formula to stabilise the foam during its formation. They reduce the surface tension between the liquid components, allowing the gas bubbles to form and grow evenly. Surfactants also help prevent bubble coalescence, which could lead to an uneven cellular structure.

Other additives

Flame retardants, antioxidants, fillers, colourants and antimicrobials may be added to improve performance as needed.