Under 655 is classed information about the printing industry and its processes (including the various techniques for production of printing surfaces, presswork and finishing), publishing and bookselling.
Printing and reproduction machines and equipment are classed under 681.6, and photographic reproduction processes under 77.
BS 1000[655]:1986 history
1986BS 1000[655]:1986 Universal Decimal Classification - English full edition - Graphic industries - Printing - Publishing - Book trade