GB497296A - Improvements in and relating to dry sealing envelopes and bags - Google Patents

Abstract

497,296. Envelopes &c. PIRIE, APPLETON, & CO., Ltd., and WOLFF, H. Aug. 20, 1937, No. 22864. [Class 146 (ii)] [Also in Group XVII] In a self-adhesive envelope or bag either the sealing flap or the back of the envelope or bag is composed of two superposed layers of paper or like material, the under layer bearing an ahesive coating and the overlying layer being apertured and furnished with a protective flap adapted in one position to cover and conceal the adhesive coating of the under layer, and in another position to expose that coating for connection with the related coating of adhesive on the complementary envelope or bag part. As shown, the back 1 of an envelope has an extension 7 which has a coating 4 of self-adhesive on its inner surfaces and is folded inside the envelope so that the adhesive lies against the back 1. The back 1 has a flap 6 cut therefrom to hinge about a line 9. The disposition of the hinge line 9 and the width of the flap 6 are such that the flap can be folded backwardly on to the back l to allow the sealing flap 2 to fold into sealing position unhindered. The coating 3 of adhesive on the sealing flap 2 is in alignment with and on the same side as the coating 4 on the extension 7 when the envelope blank is not folded. In a modification, the extension 7 is folded outwardly on to the outer face of the back wall, and is apertured and provided with a hinged flap which conceals a coating of adhesive on the outer face of the back wall. In a further modification, instead of providing an extension 7 on the back wall, a separate piece of material carrying the coating of adhesive may be secured behind the back wall.