GB1439104A - Seal construction - Google Patents

Abstract

1439104 Releasable and resealable seal construction for cartons W C VAN DORP 29 Jan 1974 04143/74 Headings B8C and B8P [Also in Divisions G2 E2 and B6] A method of forming a releasable and resealable seal between a pair of members 10, 13 which are movable into, and out of, face contact with each other comprises providing on one face surface of one of said members 10, a self-adhesive material, which material comprises a single-sided self-adhesive tape 1, the adhesive face 2 of which is adherent to the said surface face of the said one member 10; and, mounting on the non-adhesive surface of said single-sided tape a double-sided self-adhesive tape 4 and moving said members 10, 13 into face contact to cause said double-sided tape to contact and adhere directly to the other of said members 13 and thereby to seal the members together. According to the invention the strengths of the bonds between each of the self-adhesive tapes and the respective member to which each is directly bonded is greater than the strength of the bond between the non-adhesive surface of the single tape and the double-sided tape whereby, when the two members are drawn apart, the two tapes each remain adherent directly to the respective said members and the seal directly between the non-adhesive surface 3 of the singlesided tape 1 and the double-sided tape is releasably broken allowing the two members to be released and subsequently re-sealed repeatedly. As shown in Fig. 2, 4 one member comprises the front face of the box 10 and the other member comprises a tab 13 on a cover flap 11 of the box. The self-adhesive material 14, comprising single and double-sided tapes 15, 16 respectively is located on the outside surface of a letter card, Fig. 6, which has a main fold 20 and a secondary fold 21 the latter forming a flap 22, which can be folded down to contact the tape 16 and seal the card. On opening the card, the tape 16 adheres to the flap 22 the tape 15 remaining in its original position. If it is desired to mask the tape 16 it can be folded down on to the correspondence face 23 of the card. The surface 23 adjacent the fold 21 may be pre-treated with release agent such as wax. A letter card, Figs. 10-13 (not shown), has two main fold lines (30, 31), a window (33), and a closure flap (22) the self-adhesive material (14) being first secured to the card adjacent the fold (31) and a line of perforations (35) being provided to render the lower panel (36) detachable. Self-adhesive material may be provided around all of the edges of the letter cards. The sealing method can also be used in the sealing of frame cards for photographic negatives, Figs. 14-16 (not shown). The double-sided tape 16 may, prior to use, be protected temporarily by a masking strip, not shown, e.g. of waxed paper.