(written from a Production point of view)
Originally located in Kagoshima, Midori has been a Japanese manufacturer of model kits, and was in operation from the 1960s through the early 1970s. Apart from the usual car, tank and plane kits, they produced a fairly large line based upon the Irwin Allen and Gerry Anderson science fiction franchises (such as Voyage to the Bottom of the Sea , or Stingray respectively), hugely popular in Japan at the time. The remarkable thing about the Midori products was, that many, if not most of their products were endowed with toy-like properties. Most of their products could be, if so desired, equipped in the most cases with friction motors, allowing the finished and assembled products to move on their accord when wound up. A Voyage to the Bottom of the Sea submarine variation, for example, could allegedly move, when fully assembled, submerged in water. This particular feature the company apparently inherited from the former independent "KSN' half of the company which had, in the 1950s, specialized in he construction of self-propelled balsa wood flying objects.
Toward the end of its existence, the company had moved its operations to Tokyo as "Midori-Syokai, Co., Ltd." Up until that point in time it had employed a purely Japanese home market orientated marketing strategy, as all box-art and instruction sheet were only composed in Japanese. Despite a last ditch effort to try to break into the international market, by releasing the then popular "Slot Racing Cars" model-line with both boxart and instruction sheets exclusively composed in English, the company has faded from existence since then.
In the current model kit community, the Midori Sci-Fi model kits are nowadays commanding premium prices, on sites such as Ebay and Amazon.com, due to their scarceness.
Star Trek association
In 1969 Midori released two differently sized Star Trek model kits, representing the original USS Enterprise. Midori did release these on the occasion of the very first airing of Star Trek: The Original Series in Japan, the first episode of which being aired on 27 April 1969 by the Nippon Television Network Corporation.  While no scales were stated on the box-art or instruction sheets, the smaller one was measured at 14×43×4 cm, whereas the larger one measured 18×32×5 cm. Set against the established length of the AMT model of the Enterprise at 45 cm, that translated to roughly a scale of 1:2100 for the smaller one and 1:1625 for the larger one. The smaller one has proven to be the "normal" standard model kit, without any embellishments.
It was the larger one , No. 350-5, that turned out to be the "odd one out" as far as the Star Trek model community was concerned (and as evidenced by a modeler who used to own one), as it embodied the "play options", Midori was renowned for. That model featured a friction motor in the guise of a propeller sticking out of the shuttlebay, that would drive the assembled model, mounted on a wheel assembly, on any flat surface. It should be noted that neither of the two were in any way related to the AMT/Aurora products, in scale nor in tooling, and thus Midori originals.
It is unclear whether or nor not any of Mindori's products were officially licensed. No definitive answers were provided on the box-art or in the instruction sheets, as none were mentioned there. Furthermore, legalities surrounding copyright issues and such, were at the time not yet hammered out definitively for Japan at the time.
Nevertheless. Midori has, besides AMT/Aurora and Estes Industries, been the only company who, until 1992, did release Star Trek model kits.
|Midori Star Trek releases|
|USS Enterprise||1:2100||1969||150||"standard" model kit|
|1:1625||350-5||the "propeller and wheel" version|
|unknown||re-issue of unknown date, but with revised box format|