The History of Injection Molding

Injection molding has proven time and time again to be the best investment for manufacturers that are looking to speed up production processes while lowering material costs. Many people are surprised to learn just how long the injection molding process has existed. IVP Plastics is over 65 years old, but the first machine was patented over one hundred years ago.

The first injection molding machine was invented by John Wesley Hyatt and his brother, Isaiah, in 1872. Hyatt was an American inventor who is included in the National Inventors Hall of Fame. Hyatt had over 200 patents during his lifetime. If you are unfamiliar with the process, the basic concept of injection molding is to inject melted plastic into a mold, and once cooled, the plastic will retain its shape.

Hyatt's machine would have produced basic items such as buttons, combs, and billiard balls (to replace ivory). Celluloid was the first industrialized plastic which was used in an injection molding machine. However, the simple items being produced should not be overlooked. Since celluloid could be made to look like ivory or tortoiseshell, it became a popular replacement for decorative items and combs, thus eliminating much of the need to overhunt animals. Over time, more complicated and sophisticated products have been produced using injection molding. Plastic expanded in popularity during the 1940s. The war created shortages in traditional materials and plastic was able to be a successful substitute. The Du Pont Corporation invented several important new types of plastic during this time.

The next major innovation in injection molding came in 1946 when an American inventor, James Watson Hendry, built the first machine using a screw instead of a plunger to inject the mold. This improvement allowed for more speed and additional control during production. James Watson Hendry was also awarded the patent for gas-assist technology. Gas-assist is when a gas is applied to the mold cavity when a part is formed and allows for long, hollow parts. IVP Plastics was nominated for an Automotive SPE Award for using gas-assist technology on a glass filled PPS, which was the first application of its kind in North America. Our gas-assist technology uses nitrogen gas to apply uniform pressure throughout engineered resin tubing during an injection-molding process. The resulting tubes survive burst tests to 300 psi and will not corrode like metal tubing or degrade like rubber hose.

Today, injection molding has many capabilities. Some include insert molding (where an insert is molded directly into the part), in-mold labeling and decaling, color matching and pad printing. In-mold decorating creates a permanent bond melted to the substrate that resists fading and abrasion for up to 10 years, which is ideal for safety information. Plastic component color matching is available for interior automotive plastics and similar products, and pad-printing techniques allow us to print graphics on plastic parts and assemblies.

There are countless types of plastic and just as many uses. Parts and products have been injection molded for many industries including Aerospace, Agriculture, Automotive, Building Construction, Commercial Refrigeration, Electronics, Food and Beverage, Heavy Industry, Medical, and Toys.

​Injection molding plastic is our specialty. Find out for yourself how our injection molded parts can provide you with greater component performance. ​