Carbonless copy paper

Carbonless copy paper (CCP), non-carbon copy paper, or NCR paper (No Carbon Required, taken from the initials of its creator, National Cash Register) is a type of coated paper designed to transfer information written on the front onto sheets beneath. It was developed by chemists Lowell Schleicher and Barry Green, as an alternative to carbon paper and is sometimes misidentified as such.

Instead of inserting a special sheet in between the original and the intended copy, carbonless copy paper has micro-encapsulated dye or ink on the back side of the top sheet, and a clay coating on the front side of the bottom sheet. When pressure is applied (from writing or impact printing), the dye capsules rupture and react with the clay to form a permanent mark duplicating 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.

Carbonless copy paper consists of sheets of paper that are coated with micro-encapsulated dye or ink or a reactive clay. The back of the first sheet is coated with micro-encapsulated dye (referred to as a Coated Back or CB sheet). The lowermost sheet is coated on the top surface with a clay that quickly reacts with the dye to form a permanent mark (Coated Front, CF). Any intermediate sheets are coated with clay on top and dye on the bottom (Coated Front and Back, CFB).

When the sheets are written on with pressure (e.g., ball-point pen) or impact (e.g., typewriter, dot-matrix printer), the pressure causes the micro-capsules to break and release their dye. Since the capsules are so small, the resulting print is very accurate.

Carbonless copy paper was also available in a self-contained version that had both the ink and the clay on the same side of the paper.

Carbonless copy paper was first produced by the NCR Corporation. Formerly, the options were to write documents more than once or use carbon paper, which was inserted between the sheet being written upon and the copy. Carbonless paper was used as business stationery requiring one or more copies of the original, such as invoices and receipts. The copies were often paper of different colors (e.g. white original for customer, yellow copy for supplier's records, and other colors for subsequent copies). Stationery with carbonless copy paper can be supplied collated either in pads or books bound into sets, or as loose sets, or as continuous stationery for printers designed to use it.

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