Design context

Disc and string closures

This type of closure originated with the legal profession. It is used principally on envelopes and folders housing documents that need to be securely fastened and accessed quickly. It consists of discs riveted onto the opening parts. The machinery that is needed to achieve this is quite specialised, as both discs have to be riveted. One disc has a length of string attached to it that ties around the other disc in a figure-of-eight configuration.

The discs themselves tend to be made from a pressed cardboard and the string from cotton. It is possible to have these discs made from the same material as the item you are producing; however, they will not then be as strong as pressed cardboard and can buckle when tied with the string.