Dunlop and Talalay Latex
Dunlop and Talalay are two different technologies for producing latex.
Dunlop is the standard and time tested method developed in 1929, Talalay is relatively new technology which is more complex, costly and time consuming. Both methods use natural latex and can produce latex bedding products in different blends.
DUNLOP process
- Mixing of the ingredients - latex, soaps, and vulcanization agents into a compound.
- Compressed air is injected to make foam; gelling agents are also applied to help remove the mattresses and pillows from the moulds at the end of the cycle.
- The moulds are filled with the latex foam.
- The moulds enter the vulcanization oven; vulcanization lasts for about 45 minutes at 100 degrees.
- The finished mattress or pillow core is de-moulded.
- Washing the latex
- Drying
- Quality control checking firmness, density
- Packaging and storage
TALALAY process
The Talalay process is similar to the Dunlop process but includes two additional steps: Vacuum and Freeze.
When the mould is filled with the latex mixture and then closed, the pressure inside is reduced to create a vacuum, which lowers the air pressure in the mould cavity while increasing the air pressure in the foam bubbles. As a result, the foam expands and fills the mould evenly and the pressure inside the bubbles is driven to equalize over the entire latex block, leading to very uniform density. The water in the latex foam is then frozen and carbon dioxide is injected. The freezing prevents the latex particles from settling at the bottom and transforming into a solid product. This means that the finished Talalay latex mattress or pillow has very consistent density and feel from top to bottom.
Because there is no freezing stage in the Dunlop process, the rubber particles settle in the bottom of the core while the liquid latex is gelling into its solid form and so there could be slight differences in the feel and the firmness of the two sides of a Dunlop latex mattress.
The Talalay process takes four times longer and consumes five times more energy than the Dunlop process, it costs more and has much bigger carbon footprint.