Security printing

Security printing is the field of the printing industry that deals with the printing of items such as banknotes, cheques, passports, tamper-evident labels, product authentication, , postage stamps and identity cards. The main goal of security printing is to prevent forgery, tampering, or counterfeiting. More recently many of the techniques used to protect these high-value documents have become more available to commercial printers whether they are using the more traditional offset and flexographic presses or the newer digital platforms. Businesses are protecting their lesser-value documents such as transcripts, coupons and prescription pads by incorporating some of the features listed below to ensure that they cannot be forged or that alteration of the data cannot occur undetected.

A number of technical methods are used in the security printing industry.

Most banknotes are made of heavy paper, almost always from cotton fibres for strength and durability, in some cases linen or speciality coloured or forensic fibres are added to give the paper added individuality and protect against counterfeiting. Some countries, including Canada, Nigeria, Romania, Mexico, New Zealand, Israel, Singapore, Malaysia, United Kingdom and Australia, produce polymer (plastic) banknotes, to improve longevity and allow the inclusion of a small transparent window (a few millimeters in size) as a security feature that is difficult to reproduce using common counterfeiting techniques. In November 2011 Canada joined the list of countries using polymer currency as it began the introduction of a new banknote series.

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