Born in Minnesota Lakes MN, John (Jack), was the youngest of four children, moving to Marshall MN at an early age, where he spent his childhood surrounded by a large family. As with many families during that time, and in his hometown, his was a family that strongly supported, served (Jack's father and 2 brothers), and sacrificed for, the US military.

His career path, and his life-long love for chemistry, began early in his childhood, performing experiments with his brothers' ("Sonny" and "Bud") chemistry sets, while they were serving in the US military during WWII. At the age of 10, his and his family members' lives, were painfully affected by the loss of his oldest brother "Sonny" (Army Pilot First Lieutenant George H Ehrreich), who died as a transport pilot during the airborne landings in the battle of Normandy, and whom, throughout Jack's life, he admired as a heroic figure, followed by the anticipated return of his other older brother "Bud" (US Navy Pilot Ensign Albert L Ehrreich) from being downed during combat in the Pacific.

Following the completion of his undergraduate degree at the University of Minnesota, Jack moved east to obtain his Masters in Chemical Engineering at the University of Delaware, and settled in Massachusetts for the remainder of his life, performing research in several areas of materials science, founding 2 companies (Chomerics and Ercon), becoming a pioneer in conductive materials, and obtaining dozens of patents for his inventions. The products from his developments in advanced particles technologies and in coatings, adhesives, sealants, and epoxies, have been used by hundreds of millions of people over the past 6 decades. He never sought personal attention, nor fame, for his inventions. He simply wanted to discover and develop materials that could help others, and dedicated most of his life's effort to this cause, working tirelessly for many years.

Between the founding of 2 companies, he also found his first wife and love, Susan Nagy, whom he married in 1963, and with whom he started a family, having 2 children (Sandy and Dennis), and establishing a home in Wayland MA. His family's early years brought him joy, particularly while playing with his dog (Rex), fishing, mushroom hunting, and collecting, between the challenges of a nascent business. In his later years, he found his second wife and love, Yuriko Meaney, with whom he shared his joy for collecting antiques, and who predeceased him in 2008.

During his latest years, after retiring from his businesses and his work in the materials sciences, he developed a strong passion for animal habitats, even obtaining a couple of design patents on squirrel houses to protect them from predators. He would find peace in nature, on the water and in the woods, throughout his life.

Jack quietly passed away on May 23, 2023 at the age of 88 at Cape Cod Hospital in Hyannis MA, following a brief illness, surrounded by family. In addition to his 2 children (Sandy and Dennis), Jack is survived by his sister (Mary Lou Peterson of Marshall MN), 5 dear grandchildren (and 1 great-grandson), and many nieces and nephews.

A memorial gathering will be held on Thursday, June 1, 2023, between 11:00 am and 2:00 pm in the Russell & Pica Funeral Home at 17 Main Street, Lakeville MA. A memorial gathering will also be held on Monday, June 5, 2023 commencing at 10:00 am at Hamilton Funeral Home at 701 Jewett Street, Marshall MN, followed by a burial in Marshall Cemetery. In lieu of flowers, donations may be made in memory of John E Ehrreich to: St. Jude's Children's Research Hospital (To give online, please visit https://www.stjude.org/donate/) ; or, K9s For Warriors (To give online, please visit https://k9sforwarriors.org/ways-to-support/).