Paintballs are made of gelatin capsules that primarily contain polyethylene glycol and dye. Other non-toxic and water-soluble substances make up the contents of a paintball.
Paintballs, or softgels, are made out of edible food materials that are compressed by a machine called a softgel encapsulating machine. Paintballs are made by first forming hot liquid gelatin into two thin ribbons and passing them over a rotating die, forming two halves of the capsule. Next, as the dies press against each other, a filling is injected inside the gelatin sheets as they form into one. Finally, the gelatin capsules are tumbled and dried in trays before they are ready for use. The softgel encapsulating machine was first designed and patented by Robert Scherer in 1933.