Furniture leather cleaner.

Always use the non silicone leather silk. It is the “sister” of the non silicone wood silk for general dusting/polishing. Always had good results. Both available at large supermarkets

Thank you I bought some it has brought the chair up really nice.

I get a big tub from Timpson's - for best effect, I put big dollops on my hands and work it in - leave for a few others than buff with soft cloth.