Company Filing History:
22 out of 95 
2 out of 13 Years Active: 1980-2000
Title: Innovations of John C. Chang: A Pioneer in Fingerprinting and Chromogenic Technologies
Introduction
John C. Chang is a notable inventor based in Naperville, IL, whose innovations have significantly contributed to the fields of fingerprinting systems and heat-sensitive documents. With a remarkable portfolio of 24 patents, Chang has established himself as a pioneer in developing technologies that enhance security and information dissemination.
Latest Patents
Among Chang's latest inventions is a **Fingerprinting System and Method** that revolves around a substrate with a designated print image-forming area. This system incorporates a localized coating of pressure-sensitive microcapsules containing a colorless image-forming reactant, which enables the formation of visible fingerprints. An accompanying image-developing device employs a transparent film coated with a dual-functional adhesive, ensuring that the fingerprint image is preserved and developed efficiently.
Another significant patent is the **Heat-Sensitive Chromogenic System**, which produces information when heat is applied. This document includes a support bearing a visible principal image and a coating of heat-activatable chromogenic composition. This innovative system allows for the creation of a colored image through chemical reaction activated by heat, facilitating secure communication that is concealed until required.
Career Highlights
John C. Chang has had a distinguished career with companies such as Wallace Computer Services, Inc. and Wallace Business Forms, Inc. His experience in these organizations has further enhanced his capabilities as an inventor, driving him to develop groundbreaking technologies that address contemporary challenges.
Collaborations
Collaborating with talented individuals like Donald J. Hoffmann and Eric B. Wendler, Chang has capitalized on teamwork to elevate his projects and expedite the path from concept to patent. These collaborations have proven fruitful, resulting in significant advancements in the respected fields of fingerprinting and document technology.
Conclusion
John C. Chang's contributions to technology are invaluable, particularly in the realms of fingerprinting systems and heat-sensitive documents. His 24 patents reflect his dedication to innovation, highlighting his role as a key inventor in modern technology. Through his work, Chang continues to inspire emerging inventors and researchers striving to make their mark on the world.