Abstract: The mailer includes a sheet folded medially to form two plies secured one to another about their marginal edges with an intermediate ply secured about three of its four edges to one of the plies. The remaining edge of the intermediate ply forms an opening for the return envelope defined by the intermediate ply and the one ply. To enable the edge of the return envelope to be slit by automatic mail opening equipment, the intermediate ply is reversely folded along the one edge and adhesively secured to the one ply along the flap. This enables a slit to be formed very close to the edge of the return envelope whereby the return envelope may be opened without interference from the glue line securing the intermediate and one plies one to the other.

Abstract: A business form assembly is provided in which the outer or top sheet is formed with a substantially rectangular window, which must be closed at the completion of the manufacturing stage. To this end, a patch or cover sheet with dimensions slightly larger than the window, is temporarily attached, by pressure sensitive adhesive, to the sheet next adjacent the top sheet but in overlying relationship with the window. The underside of the top sheet is provided with a heat activated adhesive pattern about the periphery of the window and facing the patch or cover. When the form is substantially complete, heat is applied to activate the various lines of adhesive utilized in the form, and including the pattern about the periphery of the window. In this manner, the patch or cover becomes permanently attached to the underside of the top sheet, and is easily removed from the adjacent sheet since the heat activated adhesive is stronger than the pressure sensitive adhesive.

Abstract: A return mailer assembly comprising a pair of outer webs and an intermediate web, the first and second outer webs forming a first envelope, and the intermediate and second outer webs forming a return envelope portion, separable from the other outer web. To facilitate and increase the speed of production of such assemblies, a dry-gummed paper stock is sued for one or both of the webs which form the return envelope portion. At least one of the inner surfaces of the return envelope forming webs, as well as an envelope sealing flap portion, are provided with a gummed composition, i.e., a rewettable adhesive. A moisture barrier is applied to preselected areas of one or both of the facing, inner surfaces of the intermediate and second outer webs to prevent activation of the gummed surface, except in peripheral border portions where the return envelope forming webs are joined.

Abstract: In the perforation of webs, such as in the perforation of paper webs in the production of business forms, a single perforating cylinder is utilized in cooperation with two anvil cylinders. Perforating elements, such as interrupted blades, extend outwardly from the periphery of the perforating cylinder and are rotated into operative association with the web passing between a first anvil cylinder and the perforating cylinder, and a second anvil cylinder and the perforating cylinder, to form first and second sets of perforations spaced a predetermined desired amount along the web. The length of the web between the first and second anvil cylinders is adjustable to control precisely the spacing of the first and second sets of perforations along the web, as by passing the web over a compensator roller mounted between the first and second anvil cylinders and movable toward and away from the perforating cylinder.