GB2070085A

GB2070085A - Woven Stringer Tapes

Info

Publication number: GB2070085A
Application number: GB8005246A
Authority: GB
Original assignee: Lightning Fasteners Ltd
Current assignee: Lightning Fasteners Ltd
Priority date: 1980-02-15
Filing date: 1980-02-15
Publication date: 1981-09-03
Also published as: AU6698881A; FR2476153A1; ZA81784B

Abstract

A stringer tape is woven with zones of 1 and 1 construction separated by an intermediate zone of 2 and 2 construction, the length of the warp threads in all zones being substantially the same, whereby the intermediate zone is more relaxed than the marginal zones so that, when sewn to an article through the intermediate zone, the tape does not pucker.

Description

SPECIFICATION Woven Sliding Clasp Fastener Tape and its Manufacture This invention relates to woven sliding clasp fastener tape.

A sliding clasp fastener includes two stringers, each comprising a tape carrying a row of coupling elements, and a slider to engage and disengage the rows of elements. When such fasteners are attached by sewing to an article, the longitudinally extending portions of the tapes receiving the sewing tend to be gathered by the sewing operation. This gathering of the tapes causes the engaged rows of coupling elements, together with the associated part of the article to which the fastener is sewn, to assume an undulating shape at right angles to the plane of the fastener, thus making the fastener difficult to operate and detracting from the appearance of the article.

One method of mitigating this problem is to create surplus material in the tape to compensate for the anticipated contraction during sewing. It has, for instance, been proposed in US Patent No.

2796649 to crimp a marginal zone of a fastener tape, remote from the edge carrying coupling elements, thereby lengthening this marginal zone relative to the opposite edge which carries the coupling elements. This lengthening is calculated to compensate for the contraction resulting from sewing the tapes to an article, but unfortunately has the disadvantage that the fastener stringers become curved, or biased in their own planes, with the element-carrying edge on the inside of the curve thereby giving rise to secondary sewing-in difficulties under mass production conditions.

According to one aspect of the present invention, a sliding clasp fastener tape of woven construction has marginal zones of 1 and 1 construction separated by an intermediate zone of 2 and 2 construction, the lengths of warp threads in the three zones per unit length of a tape being substantially the same whereby the intermediate zone is of more relaxed construction than the marginal zones and can be sewn to an article without substantially puckering the tape.

The intermediate zone may have a plain weave, twill weave, broken twill weave, or herringbone weave.

According to another aspect of the invention, a method of making a woven sliding clasp fastener tape includes weaving the tape to provide marginal zones of 1 and 1 construct on separated by an intermediate zone of 2 and 2 construction and feeding warp threads for the marginal and intermediate zones at substantially the same rate to provide the intermediate zone with a more relaxed construction than the marginal zones such that the tape can be sewn to an article without substantially puckering the tape.

Preferably, the method includes feeding substantially all the warp threads for the tape from a single beam so that all the warp threads are of the same length.

The method may include feeding, from a separate warp beam, a thicker marginal warp thread for an edge of the tape that is to support coupling elements.

The method may include weaving the intermediate zone as plain weave, twill weave, broken twill weave, or herringbone weave.

The invention also includes a sliding clasp fastener made from woven sliding clasp fastener tapes as defined above, or when made in accordance with the above method, and having series of coupling elements secured along an edge of the tapes.

By virtue of the present invention, the higher crimp of warp threads in the marginal zones, caused by the high number of interlacings with the weft threads in comparison with the smaller number of interlacings in the intermediate zone will result in a more relaxed condition of warp threads in the intermediate zone. Thus the warp crimp value in the intermediate zone per unit length of tape is higher than would otherwise be the case in a similar 2 and 2 weave construction having the same thread designation.

This allows for contraction of the tape material along the sewing path during the sewing operation without producing undesirable humps or undulations in the fastener and associated article. A further advantage of the tape and fastener made according to the present invention is that they can be processed more easily on modern package dyeing machines than previous tapes and fasteners produced with a bias to avoid undulations after sewing into garments.

The invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a perspective view of part of a sliding clasp fastener during sewing thereof to an article and having a tape according to the present invention.

Figure 2 is a cross section of the fastener tape of Figure 1,and Figure 3 is a plan view of part of the fastener tape of Figure 1.

Referring to the drawings, a sliding clasp fastener tape 10 of woven construction has warp threads, for instance of cotton, 11 fed from a single warp beam, and a weft 12, for instance of nylon.

The tape has two laterally spaced marginal zones 13, 14 of plain weave, that is a 1 and 1 construction, separated by an intermediate zone 1 5 of twill weave, that isa 2 and 2 construction, which spans a path 'A' where sewing will take place when the tape is secured to an article. The.

marginal zone 13 lies near an edge 16 of the tape, which may have a thicker warp thread 1 7 of larger diameter than other warp threads to provide a beaded edge for supporting a series of coupling elements 18, the larger diameter warp thread 1 7 being fed from an auxiliary beam. Since a 1 and 1 weave generally utilizes a greater length of warp thread compared with a 2 and 2 weave, the warp threads in the twill weave of the intermediate zone 1 5 will be more relaxed and have less residual tension after weaving than warp threads in the marginal zones 1 3 and 14 for the same size of thread, the warp threads of all three zones 13, 14 and 1 5 being fed at the same rate and having the same length as they come from the same warp beam.In other words, the intermediate zone 1 5 has a warp crimp value higher then the natural warp crimp value that would exist in a similar twill weave woven without the influence of the marginal zones and may in fact have a series of low amplitude puckers 1 9 as a result of consequent lengthening of the tape in the intermediate zone. Instead of forming the intermediate zone 1 5 from a twill weave, other types of 2 and 2 construction may be used, for example plain, herringbone or broken twill.

If desired the warp threads for the three zones may have different specifications and/or be fed from separate warp threads for the intermediate zone 1 5 are more relaxed than those of the marginal zones 1 5 are more relaxed than those of the marginal zones 13 and 14. The intermediate zone 1 5 may be central as illustrated but may be arranged off-centre or split into two or more zones for a corresponding number of lines of sewing.

Since the tape 10 is substantially straight, as it has no bias in its own plane, it can be easily located between moulding tools, the beaded edge 1 6 nesting in semi-circular grooves between mould cavities for injection moulding the coupling elements 18.

The finished fastener stringer, comprising tape 10 with its series of coupling elements 18, can then be sewn to an article 20 by a line or sewing 21 along the path 'A'. The relatively loose or relaxed weave of the intermediate zone 1 5, compared with the tighter weave of the marginal zones, provides a greater mobility of threads in the intermediate zone to facilitate passage of a sewing needle and threads, and so minimises any shortening of the tape on sewing. Any small amount of shortening of the tape along the line of sewing is accommodated by the greater length of tape in the intermediate zone 1 5.

Claims

1. A woven sliding clasp fastener tape having marginal zones of 1 and 1 construction separated by an intermediate zone of 2 and 2 construction, the lengths of warp threads in the three zones per unit length of tape being substantially the same whereby the intermediate zone is of more relaxed construction than the marginal zones and can be sewn to an article without substantially puckering the tape.

2. A sliding clasp fastener tape, according to claim 1, wherein the intermediate zone is plain weave.

3. A sliding clasp fastener tape, according to claim 1, wherein the intermediate zone is twill weave.

4. A sliding clasp fastener tape, according to claim 1, wherein the intermediate zone is broken twill weave.

5. A sliding clasp fastener tape, according to claim 1, wherein the intermediate zone is herringbone weave.

6. A sliding clasp fastener tape, constructed substantially as described herein with reference to and as shown in the accompanying drawings.

7. A sliding clasp fastener made from woven sliding clasp fastener tapes according to any of the preceding claims.

8. A method of making a woven sliding clasp fastener tape including weaving the tape to provide marginal zones of 1 and 1 construction separated by an intermediate zone of 2 and 2 construction and feeding warp threads for the marginal and intermediate zones at substantially the same rate to provide the intermediate zone with a more relaxed construction than the marginal zones such that the tape can be sewn to an article without substantially puckering the tapes.

9. A method, according to Claim 8, including feeding substantially all the warp threads for the tape from a single beam so that all the warp threads are of the same length.

10. A method, according to Claim 9, including feeding, from a separate warp beam, a thicker marginal warp thread for the edge of the tape that is to support coupling elements.

11. A method, according to any of Claims 8 to 10, including weaving the intermediate zone as a plain weave.

12. A method, according to any of Claims 8 to 10, including weaving the intermediate zone as a twill weave.

13. A method, according to any of Claims 8 to 10, including weaving the intermediate zone as a broken twill weave.

14. A method, according to any of Claims 8 to 10, including weaving the intermediate zone as a herringbone weave.

1 5. A method of making a woven sliding clasp fastener tape substantially as described herein with reference to the accompanying drawings.

1 6. A sliding clasp fastener tape made according to any of Claims 8 to

15.

1 7. A method of making a sliding clasp fastener including making woven sliding clasp fastener tapes according to the method of any Claims 8 to 1 5 and securing series of coupling elements along an edge of the tapes.