Method of producing elastic garments with zippers

Abstract

It is disclosed a method for producing garments comprising separable portions and at least a zipper sewn onto said separable portions of the garment, wherein said garment undergoes shrinkage, preferably by washing, showing a wavy appearance near the zipper before shrinkage and showing a substantially plane appearance after shrinkage. Said method comprising the steps of providing an elastically stretchable zipper, said zipper in its initial un-stretched condition has the length required for the zipper in the final garment; making a garment having separable portions; stretching said zipper; sewing the stretched zipper onto said separable portions of said garment, and shrinking said garment preferably by washing, wherein after said shrinking step, said zipper is in a substantially un-stretched condition. A garment obtainable according to the steps as above is also disclosed.

Claims

1. A method for producing a garment, said garment having separable portions and at least a zipper sewn onto said separable portions of said garment, said method comprising: a) providing an elastically stretchable zipper, said zipper in its initial un-stretched condition having a length L1 required for the zipper in a final garment; b) providing a garment having separable portions, said garment being made of a fabric that undergoes a shrinkage after washing that is at least 5% of the initial length of said fabric, the shrinkage upon washing of the fabric being different from the shrinkage upon washing of the zipper; c) stretching said zipper to a length under tension that is greater than the initial non-tensioned length L1; d) sewing the stretched tensioned zipper onto said separable portions of said garment before said garment undergoes a shrinkage; and e) washing said garment whereby said garment fabric undergoes a shrinking step, wherein after said shrinking step, said zipper is in a substantially un-stretched initial condition and has said length L1.

2. The method according to claim 1, wherein said separable portions have length L2 and said zipper is stretched at least along its length in a longitudinal direction from said length L1 to said length L2.

3. The method according to claim 1, wherein after the stretched zipper is sewn on said separable portions, tension on said zipper is removed whereby the elastic zipper shrinks to said initial length L1 and provides to said garment a wavy appearance along the zipper before the washing and shrinking step of said garment.

4. The method according to claim 1, wherein said zipper is sewn onto said garment separable portions in a stretched condition corresponding to a length required for said zipper to be sewn on said garment separable portions before said shrinking.

5. The method according to claim 1, wherein said zipper length L1 of the zipper in a stretched condition is to at least 110% of the un-stretched length L1 of said zipper.

6. The method according to claim 4, wherein said zipper is stretched at least along its longitudinal direction.

7. The method according to claim 1, wherein the zipper is closed after said shrinking.

8. A garment formed according to the method of claim 1, said garment comprising at least a zipper sewn onto separable portions of the garment, characterized in that said zipper is elastically stretchable along its length and in the final garment the length of the zipper sewn on the fabric and the length of the separable portions correspond to the length of the zipper in a non-tensioned condition.

9. The garment according to claim 8, wherein said zipper is sewn onto said garment separable portions in a stretched condition corresponding to at least 110% of an un-stretched length of said zipper.

10. The garment according to claim 8, wherein said zipper is a metal zipper and said garment fabric is an elastic fabric.

11. The method according to claim 1, wherein said zipper is sewn onto said separable portions in a stretched condition corresponding to about 125% of an un-stretched length of said zipper.

12. The garment according to claim 8, wherein said zipper is sewn onto said separable portions in a stretched condition corresponding to about 125% of an un-stretched length of said zipper.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further aspects and advantages of the present invention will be discussed more in detail with reference to the enclosed drawings, given by way of non-limiting example, wherein:

(2) FIGS. 1a-e are schematic views of the zipper and the garment used in the method of producing washable garments with zippers according to the present invention.

DETAILED DESCRIPTION

(3) FIG. 1a-e show schematic representations of consecutive steps of the method of producing a washable garment 3 with a zipper 1, according to the present invention. The garment 3 does not show wavy-looking folds in the region of the garment in correspondence of the zipper 1 and the garment separable portions 2a,b, after washing the garment 3.

(4) The elastic zipper 1 shown in FIGS. 1a-e is a zipper of the type comprising metal teeth 5 and an elastic tape 4 stretchable at least along its longitudinal direction, i.e. along its length. Other embodiments of the present invention also encompass elastic zippers of the type comprising plastic teeth or nylon coils and elastic tapes stretchable along their longitudinal and transversal direction, i.e. along their length and width. FIG. 1a shows the elastic zipper 1 at its initial un-stretched condition, according to the present invention. The elastic zipper 1 at its initial un-stretched condition is longitudinally smaller than the garment separable portions 2a,b where the zipper will be sewn, because according to the present invention, the zipper 1 will be longitudinally stretched, as shown in FIG. 1b, before being sewn onto the garment 3. In particular, the initial length of the elastic zipper 1 is L1 and the length of the garment separable portions 2a,b is L2, where L1 is shorter than L2. In other words, the elastic zipper 1 is stretched along its length, in a longitudinal direction from a length L1 to a length L2. According to the present invention, the elastic zipper length L1 corresponds to the foreseen length of the garment separable portions 2a,b after washing and undergoing shrinkage.

(5) According to an exemplary embodiment of the present invention, the elastic zipper 1 is 20% shorter than the length of the garment separable portions 2a,b where it will be sewn, since it is foreseen a washing shrinkage up to the 20% of the fabric of a bi-stretch denim garment that is taken as an exemplary fabric undergoing a considerable shrinkage.

(6) In FIG. 1b the elastic zipper 1 is longitudinally stretched until it reaches the length L2 correspondent to the garment separable portions 2a,b onto which the zipper will be sewn. The elastic zipper is stretched at its open condition, since it has to be possible to let the elastic zipper tape 4 to be stretched without the constraint of the zipper teeth 5. The tension applied on the elastic zipper is represented in FIGS. 1b-c by arrows 6. Once the elastic zipper 1 is stretched, it is kept at the stretched condition, corresponding to the length L2, while it is sewn onto the garment separable portions 2a,b. FIG. 1c shows the elastic zipper 1 sewn onto the garment separable portions 2a,b in its open condition, according to the present invention. The garment separable portions 2a,b are not tensioned while the elastic zipper is sewn onto the garment. In other words, only the elastic zipper 1 is tensioned during the sewing operation and it is kept tensioned so that the zipper length during the sewing operation corresponds to the length L2 of the separable portions 2a,b of the garment 3 before they the garment is shrunk.

(7) FIG. 1d shows the garment 3 after releasing the tension forces 6 on the elastic zipper 1 already sewn onto the garment separable portions 2a,b and after closing the zipper. Since tension forces 6 are not applied to the zipper 1, it will shrink because of the elastic contraction of the zipper tape 4 along its longitudinal direction. The shrinkage of the elastic zipper causes the wavy-looking folds of the region of the garment 3 where the zipper 1 is sewn; the waves, i.e. the undulation of the fabric, mainly occurs in a direction that is vertical with respect to the plane of the fabric.

(8) At this point, the garment 3, comprising the elastic zipper 1 and the garment separable portions 2a,b in the wavy-looking corrugated state, is washed according to the present invention.

(9) After washing, the fabric of the garment 3 undergoes shrinkage and the garment separable portions 2a,b reduce them length from L2 before washing, to L1 after washing. According to the exemplary embodiment of the present invention, the bi-stretch denim fabric undergoes shrinkage of about 20% of its initial condition. The elastic zipper is not affected by washing shrinkage but since it is elastic, it will go back to its initial un-stretched condition naturally. In other words, the elastic zipper stretched to the length L2 comes back to its initial un-stretched length L1. According to the present invention, the garment separable portions 2a,b and the elastic zipper 1 are of the same length L1 after the wash, without showing wavy-looking folds.

(10) By resuming, the method of producing the garment 3 according to the present invention comprises the following steps: (a) Longitudinally stretching an elastic zipper 1 at its open condition from a length L1 corresponding to the foreseen length of the separable portions 2a,b of garment 3 that undergo shrinkage after washing, to a length L2 corresponding to the length of the separable portions 2a,b of the garment 3 before washing; (b) Sewing the elastic zipper 1 onto separable portions 2a,b of the garment 3, where the elastic zipper 1 is in a stretched and open condition and the garment separable portions 2a,b are not stretched during sewing. Both the stretched elastic zipper 1 and the garment separable portions 2a,b are long L2; (c) Washing the garment 3 comprising the elastic zipper 1 sewn onto the garment separable portions 2a,b. Before washing the garment 3, the zone of the garment in correspondence of the elastic zipper 1 shows wavy-looking folds due to the elastic zipper contraction after releasing the zipper 1 once it is sewn onto separable portions 2a,b; after washing the garment 3, the zone of the garment in correspondence of the elastic zipper 1 does not show wavy-looking folds since the fabric of the garment 3 undergoes shrinkage during washing. The elastic zipper 1 and the garment separable portions 2a,b of the garment 3 after the wash, are of the same length L1.

(11) FIG. 1e shows the product of the garment 3 after washing, according to the present invention, comprising the elastic zipper 1 fastened to the garment separable portions 2a,b. The fabric of the garment 3 is of the type that requires washing and that undergoes shrinkage after washing. The garment 3 in the final condition does not show wavy-looking folds in correspondence of the elastic zipper 1, but shows wavy-looking folds before washing. The wavy-looking folds before washing are caused by the elastic zipper 1 contraction after sewing the zipper and releasing of the tensioning forces.

(12) As a result the elastic zipper 1 and the separable portions 2a,b of the garment 3 after washing are not tensioned, they are flat and have substantially the same length L1.