What are Dunlop and Talalay Latex?


Dunlop and Talalay are two methods for manufacturing the latex foam used in bedding.

Dunlop is the standard technology, developed in 1929, while Talalay is relatively new method which is more

complex, costly and time-consuming.

Both methods use natural latex and can produce latex mattresses in any of the three blends described

above.The production process always starts with mixing liquid latex with water. There are small amounts of other

materials required for processing liquid latex into a solid form, which are necessary for all latex production. These

are natural soaps, sulphur, and gelling and vulcanization agents. When the latex mixture is ready, compressed

air is used to make foam. The foam is then poured into a mould, after which the vulcanization process begins.

The latex foam is vulcanized at a temperature over 110 degrees for about 50 minutes. The finished mattress core

is then taken out of the mould, washed and dried.

The key difference in processing in the Dunlop and Talalay methods is the two additional steps in the Talalay

technology – 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 a 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 has very

consistent density and from top to bottom. Because there is no freezing stage in the Dunlop process, the rubber

particles settle in the bottom of the mattress 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.Although the Talalay

process takes four times longer and consumes five times more energy than the Dunlop process, the two

additional process steps improve the feel, quality and consistency of the finished latex, but at high additional cost

and also with a much bigger carbon footprint.

 

Dunlop Latex Manifacturing Process


a.   The mixing of the ingredients (latex, soap, vulcanisation agents…) into compound

b.   Compressed air (necessary to make a foam)

c.   Continuous foamer

d.   Cleaning and heating of the mould

e.   Applying a special agent to be able afterwards to get the mattresses / pillows out of the moulds

1.   Filling the mould with the latex foam

2.   The mould closes and enters the vulcanisation oven

3.   Vulcanisation oven: steam at 100ºC

4.   The finished mattress / pillow core is demoulded

5.   Washing of the mattress / pillow core

6.   Drying

7.   Quality control (checking hardness, weight, visual control)

8.   Finishing

9.   Storage

 

 

Talalay Latex Manifacturing Process


a.   The mixing of the ingredients (latex, soap, vulcanisation agents…) into compound

b.   Compressed air (necessary to make a foam)

c.   Continuous foamer

d.   Cleaning and heating of the mould

e.   Applying a special agent to be able afterwards to get the mattresses / pillows out of the moulds

1.   Filling the mould with the latex foam

2.   Creating a vacuum (Specific for talalay process only)

3.   Freezing to -30°C (Specific for talalay process only)

4.   The mould closes and enters the vulcanisation oven

5.   Vulcanisation oven: steam at 100ºC

6.   The finished mattress / pillow core is demoulded

7.   Washing of the mattress / pillow core

8.   Drying

9.   Quality control (checking hardness, weight, visual control)

10.   Finishing

11.   Storage