Filter-bag for infusion products
AssigneeI.M.A. Industria Macchine Automatiche S.P.A.
InventorAndrea Romagnoli
Life of this patent
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Abstract
A filter-bag for infusion products, such as tea, camomile, or the like, formed of a blank of filter paper tape coated with a heat-sealable layer of thermoplastic material, longitudinally folded into two halves so that said layer remains in the inside and heat-sealed so as to define an infusion product containing space. A tag is attached by a thread of natural fibers retained at one end thereof between two heat-sealed edges of the bag and wound around the latter. The thread is fixed on the outside of the bag by means of heat-sealing at several points.
Claims1
A method of making a bag for infusion products such as tea which comprises the steps of:
- (a) folding a rectangular blank of filter paper coated with a thermoplastic layer in half along a fold line so that two juxtaposed sections of said blank have their thermoplastic layers facing one another;
- (b) inserting one end of a natural-fiber string between edges of said sections opposite said fold line and winding said string around said fold line so that said string lies along the filter paper of one of said sections and extends only partly across the filter paper of the other of said sections;
- (c) heat sealing the opposite end of said string between layers of a folded tag free from attachment to said sections;
- (d) providing an infusion product between said sections and heat sealing said sections together along edges thereof to form a bag and secure said one end to said bag;
- and
- (e) at a plurality of locations on each of said sections thermally fusing thermoplastic material of said sections and bonding the thermally fused thermoplastic material through the respective filter paper to said string whereby said string is detachably held to said bag at said locations, a length of said string between said tag and the one of said locations proximal to said opposite end remaining free of attachment to said other of said sections whereby said length hangs loosely from the bag.
Dependencies are inferred from the claim text.