3D printing emerged as a technology in the early 1980s, with key inventions and patents clustered around 1981–1984. Most experts point to the early 1980s as the period when 3D printing was effectively “invented.”

Earliest patents

The first widely recognized 3D‑printing–related patent was filed in 1981 by Hideo Kodama in Japan, describing a layer‑by‑layer process using UV‑cured resin to make 3D objects. This work is often cited as the foundational step that started additive manufacturing as a distinct approach to making parts.

First working 3D printers

In 1984, Chuck Hull developed stereolithography (SLA), the first practical 3D printing process using ultraviolet light to cure liquid resin layer by layer. Hull’s patent was granted in 1986, and his company later commercialized the first SLA machines, which is why he is often called the “inventor of 3D printing.”

How dates are usually stated

Because Kodama’s 1981 patent represents the first documented additive process and Hull’s 1984–1986 work produced the first commercial machines, many histories say 3D printing was “invented” in the early 1980s, especially around 1983–1984. When a single year is requested, 1981 (first patent) or 1984 (first working SLA system and key patent filing) are the two most commonly given answers.