Current methods to produce 3-D custom signs includes industrially dedicated technologies such as sandblasting, acid-etching, routing, injection molding, photoemulsion, or thermoforming vacuum molding processes. However, these processes have limitations for sign companies for a variety of reasons including capital investment, required technical expertise, difficulty and expense of a set-up for one-of-kind sign, as well as limitations in design, color, fonts, etc. Some processes, such as acid-etching, injection molding, and vacuum forming require wet chemical, molten processes or very high processing temperatures. Furthermore, process limitations, such as time-consuming and costly tooling and critical registration techniques for font and layout design (injection molding, vacuum forming), require mass produced quantities offering severely restricted design choice (color, font, layout) to the graphic designer.
Other processes that provide some degree of custom color selection typically can require critical registration techniques, or application of abradable or chippable color layers to the sign face. Many of these processes preclude integration of correctly formed Braille dots as a visually appealing part of the sign face.
In vacuum thermoforming processes, both male and female molds are used in the industry. These molds are usually reused for multiple copies. The molds do not become part of the finished sign. While backfilling of the hollow characters with a foam or other liquid resin is possible, most thermoformed signs are backlit and retain hollow characters.
Some processes use a protective overlay film around applied raised graphic characters with minimal air entrapment. While offering the latitude of electronic-cut font generation capabilities, there are limitations in the capabilities to address the visual quality of the cut raised letters, color design selection, hardness, and handling durability. However, there does not presently exist an economic means for providing 3-D signs in limited quantities or custom designs having a wide latitude of design as for flat signage construction.
Recently, the Federal Government has adopted the Americans with Disabilities Act (ADA) that requires architectural signage in all buildings and places accessible by the public to contain letters, numerals, and Braille characters that are raised off the surface of the sign. The Act specifies that the characters be raised at least 32 mils above their supporting surface, so as to be easily distinguished, even by touch by a disabled person. In addition to complying with the new legislation, the sign should also look aesthetically pleasing and be durable under heavy use conditions.