Sealing liquid for safety closures

摘要

The invention relates to a sealing liquid for sealing mailpieces containing water and a penetration agent, to the uses thereof and to letter-closing devices and franking machines containing such a sealing liquid.

主权项

1. A method of sealing a mailpiece, comprising:
providing a mailpiece envelope with a gummed flap; applying a sealing liquid to gumming on the flap or on an area of the mailpiece envelope opposite the gumming on the folded flap according to a defined laterally inhomogeneous pattern, the sealing liquid including water and a safety additive substantially not visible by immediate observation; and subsequently folding the flap and pressing the flap against an opposed surface of the mailpiece envelope; wherein the sealing liquid comprises: a) 80 to 98.9599 wt.-% water; b) 1.0 to 20 wt.-% penetration agent; c) 0.01 to 1.0 wt.-% wetting agent; d) 0.01 to 2.0 wt.-% stabilizer and/or buffer; e) 0.01 to 1.0 wt.-% dyes; f) 0.01 to 0.1 wt.-% aromatic substances; g) 0 to 0.1 wt.-% biocides and/or fungicides and/or other usual auxiliary substances; and h) 0.0001 to 2.0 wt.-% safety additive.