摘要 |
This invention pertains to methods of defining and developing first and second sets of periodic features of a web wherein neither the first set or second sets of features is readily sensed as a reliable registration element against which the location of the other can be registered. The method comprises applying registration images along the web, leading edges of the images being consistent with sufficient acuity and measurable intensity of image, and having suitable outline, to be discerned by a registration sensor. The registration images can thus serve as registration marks for determining positions along the length of the web. The web features are applied periodically along the web, forcing registration of the first set of web features to the registration images. The trim material is removed from the web, defining and developing the cut-outs in registration with ones of the first set of web features. The method uses the registration images as intermediaries, indirectly registering the cutouts and the first set of web features to each other. The method preferably includes confining the registration images to the trim areas, whereby the removing of the trim material pieces also removes the registration images. Preferably, the registration images are defined inside the trim areas, such that respective registration images are removed when corresponding trim pieces are removed. |