Medical doctors told him to stay in a dark room until he recovered his eyesight, a period which lasted several months.
After Bob's recovery, the brothers continued to experiment with these, mixing them with shellac and eventually succeeding in producing the first black light fluorescent paints.
[2] In 1938, Switzer invented Zyglo and Magnaglo, two nondestructive testing processes that use fluorescent dyes to identify defects in machined parts.
He was 83 years old[4] When Day-Glo Color Corp. was sold to Nalco in 1985, Bob and his wife used the proceeds to establish the Robert and Patricia Switzer Foundation to fund students working on applied environmental problem solving.
[4] In 2009, "The Day-Glo Brothers," a children's book about Bob and Joseph Switzer's invention of fluorescent materials, was published by author Chris Barton and illustrator Tony Persiani.