Bedding Product Comprising a Foamed Latex Layer, Slab of Such Foamed Latex Layer for Cutting a Bedding Product Therefrom and Method of Manufacturing Thereof

Abstract

A method for producing a bedding product is disclosed which has at least a foamed latex layer. The method includes pouring liquid latex foam on a conveyor belt. The liquid latex foam is vulcanized in a vulcanization station to obtain a vulcanized latex foam slab. The vulcanized latex foam slab is cut to a desired length and / or width. Electromagnetic waves with a frequency ranging between 1 and 50 Mhz are used for at least partially vulcanizing the liquid latex foam.

Description

TECHNICAL FIELD[0001]The present invention concerns bedding products and in particular mattresses and toppers, comprising a foamed latex layer.BACKGROUND OF THE INVENTION[0002]Bedding products such as toppers and mattresses made of latex foam are generally manufactured by steam vulcanization. Toppers having a thickness of maximally 6 cm are known which are produced in a continuous vulcanization process, whereby liquid latex foam is poured onto an endless belt or carrier and is subsequently passed through a steam oven. Above 6 cm thickness, continuous vulcanization is not possible because heat cannot be introduced into the core of the latex material sufficiently quickly due to the absence of aluminium pins on the conveyor belt.[0003]Furthermore, when manufacturing latex foam layers by steam vulcanization it has been observed that the foam cell diameter and the foam density varies throughout the thickness of the layer which is undesirable for fine-tuning the properties of the latex fo...

AI Technical Summary

Benefits of technology

[0026]The use of the electromagnetic waves for at least partially vulcanizing the latex foam is advantageous in that foam layers between from 1 cm to more than 6 cm, preferably even more than 8 cm and most preferably up to even 24 cm in thickness can be vulcanized showing good performance in uniform cell diameter, uniform foam density, low compression set (lower than 10%) and low indentation load deflection values. Foam densities of as low as 40 kg / m3 are achievable with the method according to the present invention.

[0029]Extensive trials with the method according to the present invention have shown that latex foam layer can be obtained with a 50% improvement in compression set (ISO1856) in view of latex foam layers vulcanized with steam vulcanization only. Other advantages of latex foam layers obtained by a method according to the present invention vs latex foam layers obtained by steam vulcanization alone include: improved resistance to loss of hardness for over more than 60000 cycles (ISO1957); improved tensile strength (ISO1798); lower correlation between density and hardness in the sense that lower foam densities can be achieved for a same hardness; improved thermoregulation (better heat absorption resulting in a improved comfort perception and faster adaptation of the foam latex to the body temperature of a person lying on the foam); and improved water absorption (up to 10% better water absorption without impact on the desorption rates).

[0030]Finally it has been found that by applying stamps on the latex foam layer during vulcanizing said liquid latex foam electromagnetic waves with a frequency ranging between 1 and 50 Mhz, patterns are created in the final foam layer, making it possible to personalize the outer surface of the latex layer easily, for example by providing a profiled logo in the top surface of the latex foam layer.EXAMPLES

Problems solved by technology

Above 6 cm thickness, continuous vulcanization is not possible because heat cannot be introduced into the core of the latex material sufficiently quickly due to the absence of aluminium pins on the conveyor belt.

Furthermore, when manufacturing latex foam layers by steam vulcanization it has been observed that the foam cell diameter and the foam density varies throughout the thickness of the layer which is undesirable for fine-tuning the properties of the latex foam layer, such as compression set and indentation load deflection values.