Blu Tack

Blu Tack is a reusable putty-like pressure-sensitive adhesive produced by Bostik, commonly used to attach lightweight objects (such as posters or sheets of paper) to walls or other dry surfaces. Traditionally blue, it is also available in other colours. Generic versions of the product are also available from other manufacturers. The spelling now used is without the hyphen.

The composition of Blu Tack is a manufacturing secret but is described as a synthetic rubber compound without hazardous properties under normal conditions. It can be swallowed without harm and is noncarcinogenic. It is non-soluble and is denser than water. The material is not flammable, but emits carbon dioxide and carbon monoxide when exposed to fire or high temperatures.

As of 2015, Bostik was manufacturing around 100 tonnes of Blu Tack weekly at its Leicester factory.

Blu Tack was originally developed in 1969 as an accidental by-product of an attempt to develop a new sealant using chalk powder, rubber and oil. The name of the inventor is unknown. Originally Blu-Tack was white, but consumer research showed fears that children may mistake it for chewing gum, and a blue colouring was added.

In the United Kingdom in March 2008, 20,000 numbered packs of pink Blu-Tack were made available, to help raise money for Breast Cancer Campaign, with 10 pence from each pack going to the charity. The formulation was slightly altered to retain complete consistency with its blue counterpart. Since then, many coloured variations have been made, including red and white, yellow and a green Halloween pack.

Similar products of various colours are made by many manufacturers, including Faber-Castell's "Tack-it", Henkel's "Fun-Tak", UHU's "Poster Putty" and "Sticky Tack","Gummy Sticker" Pritt's "Sticky Stuff" and Elmer's "Poster Tack".

Versions of the product are also sold under the generic names "adhesive putty" and "mounting putty". The generic trademark or common name for mounting putty varies by region. It is known as "Patafix" in France, Italy and Portugal (a phonetic abbreviation for pâte à fixer, "fastening dough" in French),Kennaratyggjó ("teacher's chewing gum") in Iceland, and Häftmassa ("attachment mass") or kludd in Sweden.

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Wikipedia