Durable security devices and security articles employing such devices

Abstract From the Canadian patent

Durable security devices that are resistant to chemical attack and mechanical degradation and security articles employing such devices are provided. By way , of the durable security device of the present invention opposing longitudinal , borders adjacent an information-bearing layer are sealed thereby preventing , corrosive and/or degrading materials from reaching this layer through these sealed borders. In a preferred embodiment at least a portion of the , information bearing layer is fully encapsulated thereby rendering this , portion or layer and the information conveyed thereby impervious to chemical , attack.