History of Plastic Injection Molding

In 1868, Hayate developed a plastic material, which he named celluloid. Celluloid was invented by Alexander Parkes in 1851. Hayate improved it so that it can be processed into a finished shape. Hayate and his brother Isaiah registered the patent for the first plunger injection machine in 1872. This machine is relatively simpler than the machines used in the 20th century. It basically operates like a giant hypodermic needle. This huge needle (diffusion cylinder) injects plastic into the mold through a heated cylinder.

In the 1940s World War II created a huge demand for cheap, mass-produced products. , Low-priced, mass-produced products.

In 1946, American inventor James Watson Hendry built the first injection molding machine, which allowed more precise control of the injection speed and quality of the products produced. This machine also mixes materials before injection, so that colored or recycled plastics can be thoroughly mixed and injected into virgin substances. In 1951, the United States developed the first screw injection machine, which did not apply for a patent, and this device is still in use.

In the 1970s, Hendry went on to develop the first gas-assisted injection molding process that allowed the production of complex, hollow products that were quickly cooled. This greatly improves design flexibility and strength and end-of-end manufacturing of parts, while reducing production time, cost, weight, and waste.