Piping pastry bags are manufactured from materials like plastic (polyethylene), silicone, or cloth, using processes that form them into cone shapes, often with specialized machinery for mass production of disposable bags from film rolls, ensuring food safety and durability, with manufacturers focusing on tear resistance for commercial use. Consumers can also make DIY versions from parchment paper or even Ziploc bags for quick, single-use needs, though parchment offers better non-porous performance. 

Common Manufacturers & Suppliers
Companies like A-ROO Company (USA), Ateco, Wilton, and various Chinese manufacturers (e.g., Goin Pack, Tasnee) produce piping bags, often offering custom branding and different material options.