Vegan materials in mattresses

I was interested to read your answers related to vegan appropriate mattresses, but have some further queries about the materials you use.
It is very common that latex is processed using casein (a protein found in animal milk). A few manufacturers of vegan products containing latex do source animal-free latex, as other substances can be used in place of casein. While it is not necessary to use casein, its use is widespread and generally must be assumed to be standard unless otherwise stated. Can you confirm how the latex you use is processed? Is casein or any other animal protein used during the production of the latex?
Could you also please confirm if you use wool or silk in any of the mattresses that you advertise as acceptable for vegans? Do any of the chemicals used in the fire retardants (which I fully understand you are legally obliged to use) contain any animal products, or are animal products used during their production?
Many thanks for the further clarification you can provide.