Carbon carbonless copy paper

Fluoran compounds have an optically active spiro-carbon atom. Consequently, some fluoran compounds, especially those having an alkylamino group of four or more carbon atoms at 3 -position, have been found to exhibit crystal modifications as determined by X-ray diffraction. Each crystal modification reveals different physical properties such as melting point, solubility, and affinity with acidic compounds, resulting in different characteristics regarding use for carbonless copying papers, thermosensitive recording papers, and the like. 

Carbonizing, in wool processing, 26 385 Carbonless copy paper... 

Back in the days when dinosaurs roamed the Earth and I was a boy, people inserted a messy piece of carbon paper between two pages so that a copy of the upper page would appear on the lower page. Then carbonless copy paper was invented to perform the same task without the extra sheet of carbon paper. Alas, now even carbonless copy paper is gone. 

Calnan CD (1979) Carbon and carbonless copy paper. Acta Derm Venereol Suppl (Stockh) 59 27-32 Calnan CD, Connor BL (1972) Carbon paper dermatitis due to nigrosine. Derm Beruf Umwelt 20 248-254 Cronin E (1980) Contact dermatitis. London Churchill Livingstone 853-854... 

The earliest commercial application of coacervation was for the development of carbonless carbon copy paper by the National Cash Register Company in the late 1950s. More recently, the field of polymer coacervation has developed steadily so that a more refined and complete classification of coacervation systems can be proposed here (Table 1). Other classification schemes and related principles of coacervation for microencapsulation are available in the literature with illustrated examples. " ... 

Many credit-card slips do not have carbon paper. Nevertheless, when you sign the slip, an imprint of your signature is made on the bottom copy. The carbonless paper contains tiny capsules that are filled with the colorless compound whose structure is shown here ... 

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