Abstract: An at least two-color low optical dot gain surlay pre-press color proof comprising a base having laminated thereto in the following order, a first adhesive layer, a first single-color image, and then at least one additional pair of thin adhesive layers and comprising a synthetic polymeric binder composition with a Tg of less than 105.degree. and a thickness of 8-30 microns which thickness is at least twice that of any one of said additional thin adhesive layers.

Abstract: A sheet having a set of axial markings viewable as a contour-dependent, directional image. The image is intact only when the sheet is in substantially a predetermined contour and viewed within a predetermined conical field of view. Also a method for forming such sheets.

Abstract: Printable or otherwise encodable labels are provided with features that allow an observer to judge the validity of a marking made with the label. The labels comprise a handleable support sheet and a fragile easily tearable heat-softenable film adhered to the support sheet. A visible or machine-sensible component, such as a printed image, extends over the area of the film, and the film extends beyond at least one edge of the support sheet and carries a layer of adhesive so that it can be adhered to an article that is to be marked. Upon removal of the label from an article to which it has been applied as a marking, the extending portion of the film will tear and remain adhered to the article. The removed label will not be useful if applied to another article with a portion missing; and if an attempt is made to superpose the label with the torn portion of film remaining on a different article, mismatching of the label and torn portion, e.g.

Abstract: In a self levelling ladder base of the type wherein each leg of the base has a rack and pinion assembly, the pinions being interconnected by a shaft, and a tab interfering with the pinions to prevent their rotation as weight is placed on the ladder, automatic locking means are provided to retain the tab in interfering engagement subsequent to the weight being removed, thereby increasing the operational safety of the ladder.

Abstract: A new sheet material carries specially viewable reflective legends provided by a dielectric mirror. The mirror is patterned so that the reflectivity from the mirror carries a pattern of contrasting colors. In some embodiments the mirror is incorporated into retroreflective sheet materials, and in other embodiments in specularly reflective sheet materials.