TY - BOOK DB - Science History Institute DP - Science History Institute M2 - Courtesy of Science History Institute. Rights: Public Domain Mark 1.0 TI - Benzo Colours on Cotton Yarn, Part II ID - kh04dp745 AU - Farbenfabriken vorm. Friedrich Bayer & Co. CY - Leverkusen, Germany DA - 1921/// YR - 1921 AV - VL - AN - UR - https://digital.sciencehistory.org/works/kh04dp745 AB - Part II of a sample book from Farbenfabriken vorm. Friedrich Bayer & Co.—the first incarnation of the modern pharmaceutical company Bayer AG established to manufacture and sell synthetic dyestuffs—containing mounted dyed yarn and cotton thread samples. Benzo refers to benzene, indicating the chemistry of direct cotton color from coal-tar derivatives. The samples illustrate benzo colors after treatment with formaldehyde and metallic salts, coupled with parazole FB, and diazotized and developed. The text includes directions, dye concentrations and formulas, and information on color fastness. KW - Dyes and dyeing--Yarn KW - Dyes and dyeing--Cotton LA - English ER -