Carbonless copy paper

When pressure is applied (from writing or impact printing), the dye capsules rupture and react with the clay to duplicate the markings made to the top sheet.

Intermediary sheets, with clay on the front and dye capsules on the back, can be used to create multiple copies; this may be referred to as multipart stationery.

Other dyes and supporting chemicals used are PTSMH (p-toluene sulfinate of Michler's hydrol), TMA (trimellitic anhydride), phenol-formaldehyde resins, azo dyes, DIPN (diisopropylnaphthalenes, formaldehyde isocyanates, hydrocarbon-based solvents, polycyclic aromatic hydrocarbons, polyoxypropylene diamine, epoxy resins, aliphatic isocyanates, bisphenol A, diethylene triamine, and others.

[3][4][5] PCBs are readily transferred to human skin during handling of such papers, and it is difficult to achieve decontamination by ordinary washing with soap and water.

These include adequate ventilation, humidity, and temperature controls; proper housekeeping; minimal hand-to-mouth and hand-to-eye contact; and periodic cleansing of hands.

The study also found that there were higher rates of sick leave and illness complaints at the office using large amounts of carbonless copy paper.

[11][12][13][14][15] In 2001, three employees of a medical center in San Francisco filed a lawsuit against their employer, blaming exposure to carbonless copy paper and other chemicals for their inflammatory breast cancer.