Years ago while reading Rachel Kushner’s The Flamethrowers, I went down a wiki-hole about natural rubber and the various ways it has been extracted and produced over the last two centuries, as well as the complex economies that developed around that (which were, of course, often-times very exploitative). Natural rubber is truly a fascinating material and the harvesting and manufacturing process for natural latex is beautiful to watch. This video from Discover Agriculture takes you through the process.

Natural rubber latex is traditionally converted into sheet form through careful coagulation and subsequent milling process on two roll mills. There are many types of sheet rubbers namely Ribbed smoked sheet rubber, Air-dried sheet tuber and sun-dried sheet rubber depending on the drying methodology used. Among them, Ribbed Smoked Sheet (RSS) has been the major form of raw rubber produced in Sri Lanka and Kerala. Practically entire volume of this grade of rubber is produced by small and medium scale rubber growers who own below 10 acres and between 10-50 acres respectively, scattered in the rubber growing districts in the country. This is mainly due to the simplicity and low cost of the processing machinery, easily adoptable processing technology, and the viability of the manufacturing process with any amount of latex.

The Scope of Work touches on the subject from an R&D and process perspective in their excellent newsletter, which you can read here.