Vinyl:
For a couple of generations leather-like material (Vinyl) has been made with Poly-Vinyl Chloride (PVC), which in it’s raw state is rigid and starts to decompose at * 140C. By adding additional chemicals it can be made more temperature stable and very flexible. It is still not resistant to some solvents such as acetone. The chemical additions have been subject to increased research as to their harmfulness, particularly phthalates (plasticizers).
The Consumer Product Safety Commission report “Chronic Hazard Advisory Panel on Phthalates” released late in 2014 linked phthalates to asthma, attention-deficit hyperactivity disorder, breast cancer, obesity and type II diabetes, low IQ, neurodevelopmental issues, behavioral issues, autism spectrum disorders, altered reproductive development and male fertility issues. Flame retardants (Organohalogen and Organophosphorus compounds) have also caused a great deal of concern. The use of volatile organic compounds in the manufacturing process causes fumes to be released from the final product (outgassing, also called offgassing). These fumes may cause a wide array of health issues.
Silicone:
Silicone has been applied on fiber backing for years, but had a rubber-like sticky and shiny surface that limited its use to things like shower caps and weatherproof covers. According to Wikipedia, silicones are polymers that include any inert, synthetic compound made up of repeating chains of alternating silicon (sand) atoms and oxygen atoms, frequently combined with carbon and/or hydrogen. They are typically heat-resistant and rubber-like, and are used in sealants, adhesives, lubricants, medicine, cooking utensils, and thermal and electrical insulation.
New Silicone Technology:
In the last few years, a couple of manufacturers (first Momentum, then Architex) have developed new surface treatments for silicone upholstery that that have greatly improved the look and feel of leather substitute fabrics. 100% silicone is a great way to get the look and feel of leather upholstery at a fraction of the cost, with far less maintenance.