Hi martinwolfsberger95,
I noticed that you registered with your email as your username which means that automated spambots will be able to harvest your email and add you to their spam lists. If you’d like I can remove the @ and the domain after it and change your username to just martinwolfsberger95 (or any username you wish).
Kevlar is often used to pass the fire regulations because with a flammable thread the needle holes or open seams can allow airflow through the fire barrier which can ignite the flammable materials underneath it and cause it to fail the test.
Having said that … I don’t know the specific thread that different manufacturers use in their mattresses and they would generally be the best source of information for these types of questions but I’ll make a few calls tomorrow to see if I can find out some information that may be helpful.
I would also keep in mind that most people that are looking for an “organic” mattress or materials are usually more concerned with “safety” than whether the materials have an actual organic certification and in many cases are confusing an organic certification with a safety certification. There is more information about the three different levels of organic certifications in post #2 here and some of the benefits of an organic certification in post #3 here and there is more about the different types of organic and safety certifications such as Oeko-tex, Eco-Institut, Greenguard Gold, C2C, and CertiPUR-US in post #2 here and more about some of the differences between organic and safety certifications in post #2 here and there are also some comments in post #42 here that can help you decide whether an organic certification is important to you for environmental, social, or personal reasons or whether a “safety” certification is enough.
Phoenix