The ‘loop’ tack value of a pressure sensitive material is expressed as the force required to separate, at a specified speed, a loop of material (adhesive outermost) which has been brought into contact with a specified area of a standard surface (usually glass or metal). An adhesive strip is formed into a loop and held within the jaws of a tensile tester.
然后将其压缩到标准表面上,直到在指定区域(通常为25mm x 25mm)上完全接触。然后将其以固定速度从表面上拉出以建立粘性。
结果是忽略初始峰后的平均张力力,并在纽顿(Newtons)中表示。
循环测试测试可以比较不同层压板的“初始抓取”或“应用程序钉”,并且对于使用此属性特别重要的自动标签设备的人来说非常有用。