Why does the musical "Joseph and the Amazing Technicolor Dreamcoat" use the term "technicolor"?

Technicolor
[tek-ni-kuhl-er]
Trademark.
1. a brand name for a system of making color motion pictures by means of superimposing the three primary colors to produce a final colored print.
adjective
2. (often lowercase) flamboyant or lurid, as in color, meaning, or detail.