Fastener Stringer and Slide Fastener

Abstract

A fastener tape of a fastener stringer extends beyond an edge of a fastener element closer to a connecting portion and an extension length is restricted to be smaller than 12 mm. In this way, when the fastener stringer is curved in a tape width direction of the fastener tape, it is possible to effectively suppress a tape extension portion of the fastener tape from partially floating. Thus, it is possible to stably sew the fastener stringer while maintaining the tape extension portion in an approximately flat form even when the fastener tape is curved. Moreover, since floating or the like of the sewn fastener tape occurs rarely, it is possible to prevent deterioration of the quality of external appearance.

Description

TECHNICAL FIELD

The invention relates to a slide fastener attached to seat covers, for example, for automobile seats and seat covers for sofas, and in particular, to a slide fastener configured to prevent floating or sinking of a fastener tape even when the slide fastener is curved in a tape width direction of the fastener tape.

BACKGROUND ART

Conventional slide fasteners are broadly classified into two types, a standard-type slide fastener and a concealed-type slide fastener. The standard-type slide fastener is configured such that a fastener element is attached to opposing element attaching portions of a pair of fastener tapes in a state where a coupling head of the fastener element protrudes outward from a tape side end edge at the element attaching portion. In such a standard-type slide fastener, generally, a state where at least a part of the fastener element is exposed to the outside when the left and right fastener elements are engaged is created.

On the other hand, the concealed-type slide fastener (hereinafter, referred to simply as a concealed slide fastener) is configured such that the fastener element is concealed so as not to be visible from the outside when the left and right fastener elements are engaged. In recent years, the concealed slide fastener is often used in the field of clothes, shoes, and the like from the perspective of design.

An example of such a concealed slide fastener is disclosed in JP 2008-119076 A (Patent Document 1), for example. As illustrated in FIG. 9, a concealed slide fastener 80 disclosed in Patent Document 1 is a so-called woven-type concealed slide fastener 80 configured such that a fastener element 83 is attached to a fastener tape 82 simultaneously with weaving of the fastener tape 82.

More specifically, the concealed slide fastener 80 of Patent Document 1 includes a pair of left and right fastener stringers 81 and a slider (not illustrated). Moreover, each of the left and right fastener stringers 81 includes a pair of left and right woven band-shaped fastener tapes 82 and a coil-shaped fastener element 83 woven into the fastener tapes 82.

The fastener tape 82 includes a tape body portion 82a sewn to be attached to a fastener-attached product such as clothes, a tape bent portion 82b that extends in a tape width direction from one side edge of the tape body portion 82a and is bent in a U-shape, and an element attaching portion 82c which extends further from the tape bent portion 82b and to which the fastener element 83 is woven.

The fastener element 83 is formed in a continuous shape by molding a monofilament made of a synthetic resin in a coil shape. The fastener element 83 includes a swollen coupling head 83a formed by pressing the monofilament at a predetermined interval, upper and lower leg portions 83b and 83c that extend in the tape width direction from the coupling head 83a, and a connecting portion 83d that connects the adjacent fastener elements 83.

In this case, the fastener element 83 is attached to the fastener tape 82 by weaving the upper and lower leg portions 83b and 83c into the element attaching portion 82c simultaneously with weaving of the fastener tape 82 in a state where the coupling head 83a faces the inner side of the fastener tape 82. Further, after weaving the fastener tape 82, thermosetting is performed in a state where the fastener tape 82 is bent in a U-shape in the region of the tape bent portion 82b so that the coupling head 83a of the fastener element 83 protrudes outward from the tape bent portion 82b. In this manner, the fastener stringer 81 is manufactured. And, when the obtained fastener stringers 81 are combined as two in one set, the concealed slide fastener 80 illustrated in FIG. 9 is obtained.

In the fastener stringer 81 disclosed in Patent Document 1 in particular, a plurality of upper and lower fixing warp threads 84a and 84b that pass over the outer surfaces of the upper and lower leg portions 83b and 83c of the fastener element 83 and a plurality of fastening warp threads 84c that intersect each other between the upper and lower leg portions 83b and 83c of the element and pass in a warp direction so as to alternately stride over the upper leg portion 83b and the lower leg portion 83c are disposed in the element attaching portion 82c of the fastener tape 82. Moreover, a total fineness of a lower fixing warp thread 84b that passes on a side closer to the coupling head 83a of the element than the fastening warp thread 84c among the plurality of lower fixing warp threads 84b is higher than a total fineness of the upper fixing warp thread 84a that passes on side closer to the coupling head 83a than the fastening warp thread 84c.

In this way, since the plurality of lower fixing warp threads 84b that pass on the side closer to the coupling head 83a than the fastening warp thread 84c is closely disposed, it is possible to prevent a positional shift of the lower fixing warp thread 84b even when the concealed slide fastener 80 receives a strong lateral pulling force in such a direction as to separate the left and right fastener tapes 82 in a state where the left and right fastener elements 83 are engaged. Thus, it is possible to effectively prevent formation of a gap between the tape bent portions 82b of the left and right fastener tapes 82 and to maintain an excellent concealing property of the concealed slide fastener 80.

PRIOR ART DOCUMENT

Patent Document

• Patent Document 1: JP 2008-119076 A

DISCLOSURE OF THE INVENTION

Problem to be Solved by the Invention

In recent years, by utilizing the advantages, the concealed slide fastener has been used in various products, for example, seat covers for automobile seats, seat covers for sofas, and the like, as well as various products such as clothes or shoes. Thus, it is desirable that the concealed slide fastener be configured so as to be used in various environments and conditions.

For example, when the concealed slide fastener is used for seat covers for automobile seats, the automobile seats are formed of a cushion body that is molded in a predetermined shape and is covered with the seat covers. In this case, depending on the shape or the like of the automobile seats, the concealed slide fastener is attached to the seat covers in a state where the concealed slide fastener is curved in the tape front-rear direction or the tape width direction. Moreover, from the perspective of the design of the automobile seats, the concealed slide fastener is sometimes attached to the seat covers by positively bending the concealed slide fastener in the tape front-rear direction or the tape width direction.

Meanwhile, the fastener tape used in the slide fastener is formed by weaving or sewing and is thus generally thin (has a small thickness) in the thickness direction. Moreover, the fastener tape is configured to be wide (has a large width) in the width direction in order to stably sew the slide fastener to the fastener-attached product using a sewing machine. Specifically, in the case of the conventional standard-type slide fastener or concealed slide fastener, for example, the thickness dimension of the fastener tape is set to be 1 mm or smaller. Moreover, the width dimension of the fastener tape is set so that the width dimension of the tape extension portion can have generally a size of 12 mm or more so as to smoothly perform sewing with respect to various fastener-attached products using a sewing machine.

Here, the tape extension portion is a tape region that is exposed by being extended outward more than the connecting portion of the fastener element when the fastener stringer is observed from the fastener element side. Since the larger the dimension in the tape width direction of the tape extension portion, the more accurately the fastener tape can be pressed by the foot of the sewing machine when performing sewing using the sewing machine, sewing can be stably performed.

As described above, in the conventional slide fastener, the fastener tape is formed to be thin in the thickness direction and wide in the width direction (in particular, so that the tape extension portion can have a size of 10 mm or more). Thus, when the concealed slide fastener, for example, is curved in the tape front-rear direction so as to be attached to a fastener-attached product such as seat covers, since the fastener tape itself can be bent in the thickness direction (front-rear direction) relatively easily, it is possible to neatly sew the concealed slide fastener to the fastener-attached product.

In contrast, when the concealed slide fastener, for example, is curved in the tape width direction so as to be attached to a fastener-attached product such as seat covers, when the fastener tape is curved in the tape width direction, a tape extension portion (a tape extension portion curved in a convex shape) that reaches the outer circumference side of the concealed slide fastener may partially float or sink greatly. Moreover, a large wavy wrinkle may be formed in a tape extension portion (a tape extension portion curved in a concave shape) that reaches the inner circumference side of the concealed slide fastener.

Thus, when the tape extension portion floats greatly, for example, the fastener tape is not accurately pressed by the foot of the sewing machine. Moreover, when a large wavy wrinkle is formed in the tape extension portion, for example, since the fastener tapes may partially overlap each other, it is difficult to perform sewing on the left and right fastener tapes of the concealed slide fastener using the sewing machine.

Moreover, when large floating and sinking or a wavy wrinkle occurs in the sewn fastener tape, the appearance (the quality of external appearance) of the fastener-attached product may deteriorate. Further, when the above-described large floating, sinking, or wavy wrinkle occurs in the fastener tape of the sewn concealed slide fastener, and a slider is slid along an element row, the fastener tape may rub the slider. Thus, the sliding resistance of the slider may increase, and the sliding property of the slider may deteriorate.

The invention has been made in view of the problems of the conventional technique, and a specific object of the invention is to provide a fastener stringer, and a slide fastener having the fastener stringer capable of maintaining a fastener tape in an approximately flat form to perform sewing stably when the slide fastener is curved in a tape width direction of a fastener tape so as to be sewn to a fastener-attached product, and preventing the occurrence of partial floating, sinking, or wavy wrinkles in the sewn fastener tape.

Means for Solving the Problems

In order to attain the object, a fastener stringer for a slide fastener according to the invention includes, as a basic configuration, a fastener tape and a continuous fastener element attached to one side edge portion of the fastener tape, and in which the fastener element includes a coupling head, upper and lower leg portions extending in a tape width direction from the coupling head, and a connecting portion that connects the adjacent fastener elements, and the other side edge portion of the fastener tape extends beyond an edge of the fastener element closer to the connecting portion, being mainly characterized in that: an extension length of the fastener tape in the tape width direction from a position of an end edge at the connecting portion side of the fastener element to a tape end edge of the fastener tape at the other side edge side is restricted to be smaller than 12 mm.

In particular, in the invention, it is preferable that the extension length be restricted to 10 mm or smaller and further to 6 mm or smaller.

In the fastener stringer according to the invention, it is preferable that the fastener tape be formed of fabrics and include a tape body portion and an element attaching portion disposed at one side edge side of the tape body portion, an ear portion be disposed in the other side edge portion of the tape body portion, and warp threads disposed in the ear portion have tensile strength higher than that of warp threads disposed in portions other than the ear portion of the tape body portion.

In this case, it is particularly preferable that four to six warp threads be disposed in the ear portion.

Moreover, the fastener stringer of the invention is ideally provided as a fastener stringer in which the fastener tape includes a tape body portion, a tape bent portion extending in the tape width direction from one side edge of the tape body portion so as to be bent in an U-shape, and an element attaching portion which extends further from the tape bent portion and to which the fastener element is attached, and the fastener element is attached to the element attaching portion of the fastener tape in such a manner that the coupling head protrudes outward from the tape bent portion.

In particular, the fastener stringer of the invention is further ideally provided as a fastener stringer in which the fastener element is woven into the element attaching portion simultaneously with weaving of the fastener tape.

On the other hand, the fastener stringer of the invention is ideally provided as a fastener stringer in which the fastener tape includes a tape body portion and an element attaching portion which extends in the tape width direction from one side edge of the tape body portion and to which the fastener element is attached, and the fastener element is attached to the element attaching portion of the fastener tape in such a manner that the coupling head protrudes outward from a tape side end edge at the element attaching portion side.

Further, according to the invention, a slide fastener having the fastener stringer having the above-described configuration is provided.

Effect of the Invention

The fastener tape of the fastener stringer according to the invention includes the tape extension portion disposed in the other side edge portion of the fastener tape so as to extend beyond the end edge of the fastener element at the connecting portion side. The extension length (that is, the dimension in the tape width direction of the tape extension portion) of the fastener tape in the tape width direction from the position of the end edge at the connection portion side of the fastener element to the tape end edge of the fastener tape at the other side edge side is set to be smaller than 12 mm, and preferably 10 mm or smaller, and particularly preferably 6 mm or smaller.

Since the extension length of the fastener tape is restricted to be smaller than 12 mm in this manner, when the fastener stringer is curved in the tape width direction of the fastener tape, it is possible to effectively decrease the magnitude of partial floating and sinking of the tape extension portion of the fastener tape and the magnitude of wavy wrinkling.

In particular, the inventor of the invention repeatedly performed various tests and examinations while changing the extension length of the fastener tape and found that it is preferable to restrict the extension length to 10 mm or smaller and further to 6 mm or smaller. That is, if the extension length (the dimension in the tape width direction of the tape extension portion) is 10 mm or smaller, it is possible to decrease the magnitude of floating or sinking of the tape extension portion and the magnitude of wavy wrinkling and to make them less noticeable.

Further, if the extension length is 6 mm or smaller, even when the bending (curvature) is increased so that the fastener stringer is curved in the tape width direction, it is possible to maintain the tape extension portion of the fastener tape in an approximately flat form. Thus, even when the fastener stringer is sewn to the fastener-attached product by curving the fastener stringer in the tape width direction of the fastener tape, since sewing can be performed while maintaining the tape extension portion of the fastener tape in an approximately flat form, it is possible to stably perform sewing of the fastener stringer. Further, in this case, since the tape extension portion of the fastener tape is very thin in the tape width direction, it is possible to obtain the effect of reducing the manufacturing cost of the slide fastener and decreasing the weight of the slide fastener.

Moreover, in the fastener stringer of the invention, it is possible to prevent the occurrence of partial floating, sinking, or wavy wrinkles in the fastener tape sewn to a fastener-attached product, or to make them small so as not to be noticeable even when partial floating, sinking, or wavy wrinkles occur. Therefore, it is possible to prevent deterioration of the quality of external appearance of the fastener-attached product to which the fastener stringer is sewn and attached.

Further, in a slide fastener configured using the fastener stringer, since the slider and the fastener tape rarely rub each other when the slider slides, it is possible to stably secure an excellent sliding property of the slider.

In the fastener stringer of the invention, the fastener tape is formed of fabrics, and includes the tape body portion and the element attaching portion disposed on one side edge side of the tape body portion. Moreover, the ear portion is disposed in the other side edge portion of the tape body portion, and the warp threads disposed in the ear portion have tensile strength higher than that of the warp threads disposed in portions other than the ear portion of the tape body portion.

In this way, it is possible to stably hold the form of the fastener tape in which the width dimension of the tape extension portion is restricted. Thus, since it is possible to more reliably prevent the occurrence of floating, sinking, or wavy wrinkles in the tape extension portion when the fastener stringer is curved, sewing of the fastener stringer can be more easily performed. Moreover, since the warp threads disposed in the ear portion have high tensile strength, it is possible to stabilize the woven fabrics of the tape body portion on the inner side of the ear portion and to expand the degree of freedom in the choice of woven fabrics employed in the fastener tape.

In this case, four to six warp threads are disposed in the ear portion of the fastener tape. Since four or more warp threads are disposed in the ear portion, it is possible to more stably hold the form of the fastener tape. In particular, it is possible to stably bend the weft threads in the ear portion even when the weft threads have strong tensile strength and to stably hold the form of the fastener tape. On the other hand, since six or smaller warp threads are disposed in the ear portion, it is possible to prevent the tensile strength in a portion of the fastener tape at the ear portion side from becoming too strong, to prevent the portion of the fastener tape at the ear portion side from being contracted too much, and to prevent the occurrence of so-called bias in the fastener tape.

The invention is ideally applied to a fastener stringer for a so-called concealed slide fastener, in which the fastener tape includes the tape body portion, the tape bent portion extending in the tape width direction from one side edge of the tape body portion so as to be bent in an U-shape, and the element attaching portion which extends further from the tape bent portion and to which the fastener element is attached, and the fastener element is attached to the element attaching portion of the fastener tape in such a manner that the coupling head protrudes outward from the tape bent portion.

In this case, the fastener stringer of the invention can form a fastener stringer in which the fastener element is woven into the element attaching portion simultaneously with weaving of the fastener tape.

Further, the invention is ideally applied to a so-called standard-type fastener stringer in which the fastener tape includes the tape body portion and the element attaching portion which extends in the tape width direction from one side edge of the tape body portion and to which the fastener element is attached, and the fastener element is attached to the element attaching portion of the fastener tape in such a manner that the coupling head protrudes outward from the tape side end edge at the element attaching portion side.

In the fastener stringer for the slide fastener or the standard-type fastener stringer according to the invention, even when the fastener stringer is curved in the tape width direction of the fastener tape, it is possible to prevent the occurrence of partial floating, sinking, or wavy wrinkles in the tape extension portion of the fastener tape, or to make them small so as not to be noticeable even when partial floating, sinking, or wavy wrinkles occur.

Moreover, in the slide fastener of the invention having the fastener stringer having the above-described configuration, the dimension in the tape width direction of the tape extension portion of the fastener tape is set to be smaller than 12 mm, and preferably 10 mm or smaller, and particularly preferably 6 mm or smaller. Thus, when the slide fastener of the invention is sewn to be attached to a fastener-attached product in a state where the slide fastener is curved in the tape width direction, it is possible to stably perform sewing of the fastener stringer.

Moreover, in the slide fastener sewn to be attached to a fastener-attached product, it is possible to prevent the occurrence of partial floating, sinking, or wavy wrinkles in the fastener tape, or to make them small so as not to be noticeable even when partial floating, sinking, or wavy wrinkles occur. Thus, it is possible to prevent deterioration of the quality of external appearance of the fastener-attached product. Moreover, in this case, since the slider and the fastener tape rarely rub each other when the slider slides, it is possible to stably secure an excellent sliding property of the slider.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a rear view illustrating the rear side of a concealed slide fastener according to a first embodiment of the invention.

FIG. 2 is a cross-sectional view schematically illustrating a cross-section of the concealed slide fastener.

FIG. 3 is a copy of the picture of the rear side of the concealed slide fastener.

FIG. 4 is a copy of the picture of a front side of the concealed slide fastener.

FIG. 5 is a rear view illustrating a state where the concealed slide fastener is curved in a tape width direction.

FIG. 6 is a cross-sectional view of a concealed slide fastener according to a second embodiment of the invention.

FIG. 7 is a front view of a slide fastener according to a third embodiment of the invention.

FIG. 8 is a cross-sectional view of the slide fastener.

FIG. 9 is a cross-sectional view illustrating the conventional concealed slide fastener.

MODE(S) FOR CARRYING OUT THE INVENTION

Hereinafter, modes for carrying out the invention will be described in detail with reference to the drawings. The invention is not limited to the embodiments described below, and various changes can be made as long as substantially the same configuration and the same function and effect as the invention are implemented.

For example, although a continuous fastener element described in the following embodiment is formed by molding a monofilament in a coil shape, the invention is not limited to this, and the continuous fastener element may be formed by molding the monofilament in a zigzag shape.

First Embodiment

FIG. 1 is a rear view illustrating the rear side of a concealed slide fastener according to a first embodiment, and FIG. 2 is a cross-sectional view schematically illustrating a cross-section of the concealed slide fastener in a comprehensible way. Moreover, FIG. 3 is a copy of the picture of the rear side of the concealed slide fastener, and FIG. 4 is a copy of the picture of a front side of the concealed slide fastener.

In FIG. 2, the cross-section of a concealed slide fastener in which the left and right fastener elements are engaged is schematically shown in order to make the state of warp threads of a fastener tape understood better. For convenience of the drawings, a state where the tape bent portions of the left and right fastener tapes are separated from each other is shown although the left and right fastener elements are engaged with each other. In an actual concealed slide fastener, when the left and right fastener elements are engaged, as will be described below, the tape bent portions of the left and right fastener tapes are in contact with each other so that the fastener elements can be concealed so as not to be visible from the outer surface.

Moreover, in the following description, a forward-backward direction indicates a longitudinal direction of a fastener tape, which is the same direction as a sliding direction in which a slider slides. Also, a horizontal direction indicates a tape width direction of a tape body portion of the fastener tape, which is parallel to a tape surface of the tape body portion and is orthogonal to the tape longitudinal direction.

Further, a vertical direction indicates a tape front-rear direction orthogonal to the tape surface of the fastener tape, and in particular, a direction of a side of the fastener tape to which a fastener element is attached is defined as an upper side and the opposite direction is defined as a lower side. In this case, the lower surface side of the concealed slide fastener is a front surface side of the concealed slide fastener exposed to the outside.

A concealed slide fastener 10 according to the first embodiment is used by being attached to a fastener-attached product such as seat covers of automobile seats, for example. The concealed slide fastener 10 includes a pair of left and right fastener stringers 20 in which an element row 22 is formed, a top stop 11 fixed to a front end side of the element row 22 of each fastener stringer 20, a bottom stop 12 fixed to a rear end side of the element row 22 of each fastener stringer 20, and a concealed slide fastener slider 13 attached so as to be slidable along the element row 22.

The concealed slide fastener 10 is configured such that the slider 13 is slid toward the top stop 11 to allow the left and right element rows 22 to engage with each other to close the concealed slide fastener 10, and the slider 13 is slid toward the bottom stop 12 to allow the left and right element rows 22 to be separated from each other to open the concealed slide fastener 10. The top stop 11, the bottom stop 12, and the concealed slide fastener slider 13 of the concealed slide fastener 10 have the same configuration as those generally used in the conventional art.

In the first embodiment, each of the left and right fastener stringers 20 includes a sewn fastener tape 21 and a coil-shaped fastener element 23 attached to the fastener tape 21, and the coil-shaped continuous fastener element 23 is woven into the fastener tape 21, whereby the element row 22 is formed.

The fastener tape 21 includes an element attaching portion 21a in which the fastener element 23 is woven, a tape bent portion 21b that extends in the tape width direction from one side edge of the element attaching portion 21a so as to be bent in an U-shape, and a tape body portion 21c that extends further from the tape bent portion 21b and is a portion woven to a fastener-attached product.

The fastener element 23 includes a coupling head 23a formed by molding a monofilament made of a thermoplastic resin such as polyamide or polyester into a coil shape, upper and lower leg portions 23b and 23c formed so as to extend in the tape width direction from the coupling head 23a, and a connecting portion 23d that connects an edge end portion of the upper leg portion 23b or the lower leg portion 23c to the lower leg portion 23c or the upper leg portion 23b of a fastener element 23 that is adjacent in the forward-backward direction. The fastener element 23 is attached to the element attaching portion 21a of the fastener tape 21 in a state where the coupling head 23a protrudes outward from the tape bent portion 21b of the fastener tape 21.

The fastener tape 21 of the first embodiment is woven by inserting a ground weft thread 24a in an opening of a warp thread by reciprocating a carrier bar, and as illustrated in FIG. 2, the tape body portion 21c and the tape bent portion 21b are fabrics that are woven from the ground weft thread 24a formed of a two-folded yarn and a plurality of ground warp threads 24b. Moreover, a knitting needle (not illustrated) is inserted into a tape end edge on a side of the tape body portion 21c opposite to the side where the tape bent portion 21b is formed, and the ground weft threads 24a at the next positions are successively hooked to join the loop-like bent ends.

An upper fixing warp thread 24c that passes in the warp direction over the upper surface side of the upper leg portion 23b of each fastener element 23, a lower fixing warp thread 24d that passes in the warp direction over the lower surface side of the lower leg portion 23c of each fastener element 23, a fastening warp thread 24e that passes in the warp direction so as to intersect each other between the upper and lower leg portions 23b and 23c, a positioning warp thread 24f that restricts the positions in the weft direction of the upper and lower fixing warp threads 24c and 24d, and a ground weft thread 24a that is inserted into the tape body portion 21c and the tape bent portion 21b are disposed in the element attaching portion 21a of the fastener tape 21. Since the element attaching portion 21a is formed using these warp threads 24c, 24d, 24e, and 24f and the ground weft thread 24a, it is possible to tightly weave the fastener element 23 into the element attaching portion 21a and to stabilize the attachment state of the fastener element 23.

Moreover, polyester textured yarns having a thickness in the range from 160 decitex to 550 decitex are used for the various types of warp threads 24b to 24f disposed in the element attaching portion 21a, the tape bent portion 21b, and the tape body portion 21c of the fastener tape 21, and polyester textured yarns having a thickness in the range from 550 decitex to 1100 decitex are used for the single yarns of the ground weft thread 24a.

In particular, in the case of the first embodiment, the various types of warp threads 24b to 24f disposed in the element attaching portion 21a, the tape bent portion 21b, and the tape body portion 21c have a thickness of 330 decitex, and the single yarns of the ground weft thread 24a have a thickness of 700 decitex. In the invention, the thickness and material of the ground weft thread and various warp threads are not particularly limited, but can be appropriately changed according to the size of the fastener element and the purpose or the like of the concealed slide fastener.

In the concealed slide fastener 10 of the first embodiment, the tape body portion 21c of the fastener tape 21 includes a tape extension portion 25 that extends beyond an end edge of the fastener element 23 at the connecting portion 23d side. That is, in the concealed slide fastener 10 of the first embodiment, when the position of the end edge of the fastener element 23 at the connecting portion 23d side in relation to the horizontal direction of the concealed slide fastener 10 is used as a reference position, the dimension in the tape width direction of the tape body portion 21c is set so that an extension length X from the reference position to a tape end edge of the fastener tape 21 at the tape body portion 21c side satisfies a range of X>0 mm. In this case, when the concealed slide fastener 10 is observed from the fastener element 23 side, the tape extension portion 25 is exposed to the outside more than the connecting portion 23d of the fastener element 23.

By setting the extension length X from the reference position to the tape end edge to satisfy the range of X>0 mm in this manner, it is possible to reliably provide the tape extension portion 25 to the left and right fastener tapes 21. In this manner, when the fastener tape 21 is formed while weaving the fastener element 23 therein using a loom as will be described below, it is possible to smoothly weave the fastener tape 21 while pulling (conveying) the tape extension portion 25 of the woven fastener tape 21 between upper and lower rollers (not illustrated) on the downstream side of the loom. Thus, it is possible to stably weave the fastener tape 21 having a desired woven fabric with high accuracy while preventing flipping over or bending of the fastener tape 21.

Further, in the first embodiment, the dimension in the tape width direction of the tape extension portion 25 of the fastener tape 21 is restricted to 6 mm or smaller. That is, the dimension in the tape width direction of the tape body portion 21c is set so that the extension length X from the reference position to the tape end edge of the fastener tape 21 at the tape body portion 21c side satisfies a range of 0 mm<X≦6 mm.

In this case, since the thickness of the ground warp thread 24b disposed in the tape body portion 21c is set to 330 decitex as described above, and the tape extension portion 25 has, for example, a width dimension of 3 mm, approximately twenty ground warp threads 24b are disposed in the tape extension portion 25 (FIG. 2 illustrates the cross-section while decreasing the number of ground warp threads 24b disposed in the tape extension portion 25 in order to easily understand the features of the concealed slide fastener 10 of the first embodiment). Moreover, in the first embodiment, by decreasing the number of warp threads disposed in the tape body portion 21c of the fastener tape 21 (specifically, the number of warp threads disposed in the tape body portion 21c other than an ear portion 26 described below), the dimension in the tape width direction of the tape extension portion 25 of the fastener tape 21 is restricted.

In this manner, since the extension length X (the dimension in the tape width direction) of the tape extension portion 25 is 6 mm or smaller, when the concealed slide fastener 10 (the fastener stringer 20) is curved in the tape width direction of the fastener tape 21 as illustrated in FIG. 5, for example, it is possible to effectively prevent the tape extension portion 25 from partially floating or sinking and to prevent the occurrence of wavy wrinkles in the tape extension portion 25. Thus, it is possible to maintain the tape extension portion 25 in a flat form.

In this case, the shorter the extension length X, the easier it is to maintain the tape extension portion 25 in a flat form even when the fastener stringer 20 is curved in the tape width direction. However, if the dimension in the tape width direction of the tape extension portion 25 decreases, it may be difficult to sew the fastener stringer 20 when the tape body portion 21c of the fastener stringer 20 is sewn to be attached to a fastener-attached product.

That is, in the concealed slide fastener 10 of the first embodiment, when the extension length X from the reference position of the fastener tape 21 to the tape end edge is in the range of 0 mm<X≦2 mm, even when the fastener stringer 20 is greatly curved in the tape width direction, it is possible to suppress the tape extension portion 25 from partially floating more effectively than when the extension length X is in the range of 4 mm<X≦6 mm. Thus, it is possible to stably hold the tape extension portion 25 in a flat form.

On the other hand, for example, when the extension length X from the reference position of the fastener tape 21 to the tape end edge is in the range of 4 mm<X≦6 mm, it is possible to press the tape body portion 21c of the fastener tape 21 with the foot of a sewing machine more stably when sewing the fastener stringer 20 to a fastener-attached product using the sewing machine, for example, as compared to when the extension length X is in the range of 0 mm<X≦2 mm. Thus, it is possible to perform sewing of the fastener stringer 20 more smoothly.

Moreover, when the extension length X from the reference position of the fastener tape 21 to the tape end edge is in the range of 2 mm<X≦4 mm, for example, it is possible to hold the tape extension portion 25 in a flat form when the fastener stringer 20 is greatly curved in the tape width direction. Moreover, it is possible to perform sewing of the fastener stringer 20 smoothly when sewing the fastener stringer 20 to a fastener-attached product. In the first embodiment, the size of the extension length X of the fastener tape 21 may be selected optionally within the range of 0 mm<X≦6 mm according to the purpose or the like of the concealed slide fastener 10.

Moreover, in the concealed slide fastener 10 of the first embodiment, the tape body portion 21c of the fastener tape 21 has an ear portion 26 disposed in a tape side edge portion on a side opposite to the tape bent portion 21b, and the ground warp thread 24b disposed in the ear portion 26 has tensile strength higher than that of the ground warp thread 24b disposed in portions other than the ear portion 26 of the tape body portion 21c. In this manner, since the ground warp thread 24b disposed in the ear portion 26 has high tensile strength, as shown by the copy of the picture of the concealed slide fastener 10 in FIGS. 3 and 4, for example, the ground warp thread 24b disposed in the ear portion 26 becomes in a state where it extends more strongly than the ground warp thread 24b disposed in the inner side.

In this case, the number of ground warp threads 24b disposed in the ear portion 26 is preferably set in the range from 4 to 6, and in the first embodiment, six warp threads having high tensile strength are disposed in the ear portion 26. Since four or more high-tensile-strength warp threads are disposed in the ear portion 26 of the fastener tape 21, even when the tensile strength applied to the ground weft thread 24a is high (strong) or when the fastener tape 21 is curved in the tape width direction, it is possible to prevent an end edge of the fastener tape 21 at the ear portion 26 side from being twisted or bent and to stably hold the shape of the fastener tape 21.

Moreover, since four or more high-tensile-strength warp threads are disposed in the ear portion 26, it is possible to stabilize the woven fabrics of the fastener tape 21 on the inner side of the ear portion 26, and for example, even when the concealed slide fastener 10 is washed, it is possible to prevent the position of woven patterns from being shifted. Further, it is possible to greatly expand the degree of freedom in the choice of woven fabrics employed in the fastener tape 21.

On the other hand, since six or smaller high-tensile-strength warp threads are disposed in the ear portion 26 of the fastener tape 21, it is possible to prevent the tensile strength in the tape longitudinal direction of the ear portion 26 of the fastener tape 21 from becoming too strong. In this way, it is possible to prevent the occurrence of a so-called biased state in the fastener stringer 20, the state being a state where the entire fastener tape 21 is curved so that the tape side edge portion of the fastener tape 21 at the ear portion 26 side is contracted greatly and the tape side edge portion has a concave shape.

Next, a method of manufacturing the concealed slide fastener 10 according to the first embodiment will be described. First, the fastener stringer 20 is manufactured. Specifically, a weft thread is inserted into the openings of warp threads disposed in a predetermined number by reciprocating a carrier bar using a loom to form the fastener tape 21 having a predetermined dimension in the tape width direction in a desired woven fabric. In this case, the tensile strength of the warp thread is adjusted so that the tensile strength of the ground warp thread 24b disposed in the ear portion 26 of the fastener tape 21 is increased, whereby the fastener tape 21 is woven.

Moreover, simultaneously with the weaving of the fastener tape 21 in this manner, the coil-shaped fastener element 23 molded of a monofilament is woven into the element attaching portion 21a of the fastener tape 21 in a state where the coupling head 23a faces the inner side of the fastener tape 21.

Subsequently, after the fastener tape 21 is woven, a tape portion of the fastener tape 21 that becomes the tape bent portion 21b is bent in a U-shape so that the coupling head 23a of the fastener element 23 protrudes outward from the U-shaped tape bent portion 21b. Further, a thermosetting process is performed on the fastener tape 21 having such a bent shape. In this manner, the fastener stringer 20 for the concealed slide fastener in which the coupling head 23a protrudes outward from the tape bent portion 21b is obtained.

Further, the two obtained fastener stringers 20 are combined together, and the slider 13 is slidably attached to the element rows 22 of the fastener stringers 20, whereby the concealed slide fastener 10 of the first embodiment is manufactured. In the concealed slide fastener 10, when the left and right fastener elements 23 are engaged, the tape bent portions 21b of the left and right fastener tapes 21 can be brought into contact with each other. Therefore, when the concealed slide fastener 10 is observed from the lower surface side (the side exposed to the outside), the left and right fastener elements 23 in the engaged state can be concealed by the fastener tape 21 (in particular, the tape bent portion 21b and the tape body portion 21c).

In the concealed slide fastener 10 of the first embodiment manufactured in the above-described manner, the extension length X (the dimension in the tape width direction) of the tape extension portion 25 of the fastener tape 21 is set to 6 mm or smaller that is extremely small than that of the conventional concealed slide fastener 10. Thus, it is possible to reduce the manufacturing cost of the concealed slide fastener 10 and to reduce the weight. Moreover, even when the concealed slide fastener 10 is curved in the tape width direction of the fastener tape 21 as illustrated in FIG. 5, it is possible to effectively suppress the tape extension portion 25 of the fastener tape 21 from partially floating or sinking and to prevent the occurrence of wavy wrinkles in the tape extension portion 25. Thus, it is possible to maintain the tape body portion 21c of the fastener tape 21 in an approximately flat form.

Thus, when the concealed slide fastener 10 of the first embodiment is sewn to be attached to a fastener-attached product such as automobile seat covers in a state where the concealed slide fastener 10 is curved in the tape width direction of the fastener tape 21, it is possible to decrease or prevent the occurrence of swelling in the tape front-rear direction of the fastener tape 21 when the tape body portion 21c (in particular, the position of the tape body portion 21c at the tape bent portion 21b) of the fastener tape 21 and the fastener-attached product are sewn and attached together. Thus, it is possible to stably perform sewing of the concealed slide fastener 10 (or the fastener stringer 20) while maintaining the tape body portion 21c of the fastener tape 21 in an approximately flat form.

Further, even after the concealed slide fastener 10 of the first embodiment is sewn to be attached to the fastener-attached product in a state where the concealed slide fastener 10 is curved in the tape width direction of the fastener tape 21, it is possible to prevent the occurrence of partial floating, sinking, or wavy wrinkles in the fastener tape 21 or to make them small so as not to be noticeable even when partial floating, sinking, or wavy wrinkles occur. Therefore, it is possible to prevent deterioration of the quality of external appearance of the fastener-attached product to which the concealed slide fastener 10 is sewn and attached.

Moreover, when the slider 13 is slid to open the concealed slide fastener 10, since the occurrence of partial floating, sinking, or wavy wrinkles in the fastener tape 21 of the concealed slide fastener 10 is prevented or is small, the sliding resistance of the slider 13 may not increase due to the rubbing of the slider 13 and the fastener tape 21, and deterioration of the sliding property of the slider 13 can be prevented.

Moreover, in the concealed slide fastener 10 of the first embodiment, four to six warp threads having such high tensile strength as described above are disposed in the tape side edge portion of the fastener tape 21 at the tape body portion 21c side, whereby the ear portion 26 is formed. In this way, it is possible to stably hold the form (in particular, the form of the tape body portion 21c) of the fastener tape 21. Thus, when the concealed slide fastener 10 is curved in the tape width direction so as to be sewn to the fastener-attached product, it is possible to hold the tape extension portion 25 of the fastener tape 21 in an approximately flat form more reliably and to neatly perform sewing of the concealed slide fastener 10 more stably.

Second Embodiment

FIG. 6 is a cross-sectional view of a concealed slide fastener according to a second embodiment.

A concealed slide fastener 30 according to the second embodiment is configured such that unlike the first embodiment described above, the fastener element 43 is not woven into the element attaching portion simultaneously with the weaving of the fastener tape, but the fastener element 43 is sewn to be attached to the element attaching portion 41a of the fastener tape 41 after the fastener tape 41 is woven in a predetermined tape width dimension. Hereinafter, the concealed slide fastener 30 of the second embodiment will be described in detail.

The concealed slide fastener 30 of the second embodiment includes a pair of left and right fastener stringers 40 having an element row formed of a fastener element 43, a top stop (not illustrated) fixed to a front end side of the element row of each fastener stringer 40, a bottom stop (not illustrated) fixed to a rear end side of the element row of each fastener stringer 40, and a concealed slide fastener slider (not illustrated) attached to as to be slidable along the element row.

Each of the left and right fastener stringers 40 includes a woven fastener tape 41 and a coil-shaped fastener element 43 sewn to be attached to the fastener tape 41, and when the fastener element 43 is sewn to be attached to the fastener tape 41, an element row is formed.

The fastener tape 41 includes an element attaching portion 41a sewn to be attached to the fastener element 43, a tape bent portion 41b that extends in the tape width direction from one side edge of the element attaching portion 41a so as to be bent in an U-shape, and a tape body portion 41c that extends further from the tape bent portion 41b and is a portion woven to a fastener-attached product.

In this case, polyester textured yarns having a thickness of 330 decitex are used for the various types of warp threads disposed in the element attaching portion 41a, the tape bent portion 41b, and the tape body portion 41c, and polyester textured yarns having a thickness of 700 decitex are used for the single yarns of the weft threads.

The fastener element 43 includes a coupling head 43a, upper and lower leg portions 43b and 43c formed so as to extend in the tape width direction from the coupling head 43a, and a connecting portion 43d that connects an extension end portion of the upper leg portion 43b or the lower leg portion 43c to the lower leg portion 43c or the upper leg portion 43b of an element that is adjacent in the forward-backward direction.

Moreover, the fastener element 43 is sewn to be attached to the element attaching portion 41a of the fastener tape 41 by sewing a sewing thread 47 to draw a double ring in a state where a core thread 48 is inserted between the upper and lower leg portions 43b and 43c, and the coupling head 43a protrudes outward from the tape bent portion 41b of the fastener tape 41.

In the concealed slide fastener 30 of the second embodiment, the fastener tape 41 includes a tape extension portion 45 that extends outward more than the connecting portion 43d of the fastener element 43 so as to be exposed to the outside when the concealed slide fastener 30 is observed from the fastener element 43 side. That is, in the concealed slide fastener 30 of the second embodiment, when the position of an end edge of the fastener element 43 at the connecting portion 43d side in relation to the horizontal direction of the concealed slide fastener 30 is used as a reference position, a dimension in the tape width direction of the tape body portion 41c is set so that an extension length X from the reference position to a tape end edge of the fastener tape 41 at the tape body portion 41c side satisfies a range of X>0 mm.

By setting the extension length X from the reference position to the tape end edge to satisfy the range of X>0 mm in this manner, it is possible to provide the tape extension portion 45 to the left and right fastener tapes 41. In this manner, in manufacturing of the concealed slide fastener 30, for example, when the concealed slide fastener 30 is conveyed in a state of a fastener chain in order to perform a thermosetting process, a dying process, or the like on the fastener tape 41, it is possible to reliably put the tape extension portion 45 of the fastener tape 41 so as to be placed between upper and lower rollers. Thus, it is possible to stably perform a predetermined process on the fastener chain while preventing flipping over or bending of the fastener tape 41.

Moreover, in the concealed slide fastener 30 of the second embodiment, a dimension in the tape width direction of the tape extension portion 45 of the fastener tape 41 is restricted to 6 mm or smaller. That is, the dimension in the tape width direction of the tape body portion 41c is set so that the extension length X from the reference position to the tape end edge of the fastener tape 41 at the tape body portion 41c side satisfies the range of 0 mm<X≦6 mm.

Further, in the concealed slide fastener 30 of the second embodiment, the tape body portion 41c of the fastener tape 41 has an ear portion 46 disposed in a tape side edge portion on a side opposite to the tape bent portion 41b, and the warp thread disposed in the ear portion 46 has tensile strength higher than that of the warp thread disposed in portions other than the ear portion 46 of the tape body portion 41c. In this case, six warp threads having high tensile strength are disposed in the ear portion 46. In this way, it is possible to stabilize the form of the fastener tape 41 without causing a bias in the fastener tape 41.

In the concealed slide fastener 30 of the second embodiment having the above-described configuration, the extension length X of the tape extension portion 45 of the fastener tape 41 is restricted to 6 mm or smaller. Moreover, the ear portion 46 in which the warp threads having high tensile strength are disposed is formed in the tape side edge portion of the fastener tape 41 at the tape body portion 41c side. Thus, the concealed slide fastener 30 of the second embodiment can provide the same advantages as those of the concealed slide fastener 30 according to the first embodiment described above.

Third Embodiment

FIG. 7 is a front view of a slide fastener according to a third embodiment, and FIG. 8 is a cross-sectional view of the slide fastener.

A standard-type slide fastener 50 (hereinafter, the standard-type slide fastener will be referred to simply as a “slide fastener”) according to the third embodiment includes a pair of left and right fastener stringers 60 in which an element row 62 is disposed, a top stop 51 fixed to a front end side of the element row 62 of each fastener stringer 60, a bottom stop 52 fixed to a rear end side of the element row 62 of each fastener stringer 60, and a slider 53 attached so as to be slidable along the element row 62. In this case, the top stop 51, the bottom stop 52, and the slider 53 have the same configuration as those generally used in the conventional art.

In the third embodiment, each of the left and right fastener stringers 60 includes a woven fastener tape 61 and a coil-shaped fastener element 63 sewn to be attached to the fastener tape 61, and when the fastener element 63 is sewn to be attached to the fastener tape 61, an element row 62 is formed.

The fastener tape 61 includes an element attaching portion 61a to which the fastener element 63 is sewn and attached and a tape body portion 61b that extends in the tape width direction from one side edge of the element attaching portion 61a so as to be sewn to a fastener-attached product. In this case, polyester textured yarns having a thickness of 330 decitex are used for a plurality of warp threads disposed in the element attaching portion 61a and the tape body portion 61b, and polyester textured yarns having a thickness of 700 decitex are used for the single yarns of the weft threads.

The fastener element 63 includes a coupling head 63a, upper and lower leg portions 63b and 63c formed so as to extend in the tape width direction from the coupling head 63a, and a connecting portion 63d that connects an extension end portion of the upper leg portion 63b or the lower leg portion 63c to the lower leg portion 63c or the upper leg portion 63b of the element that is adjacent in the forward-backward direction.

Moreover, the fastener element 63 is sewn to be attached to the element attaching portion 61a by sewing a sewing thread 67 to draw a double ring in a state where a core thread 68 is inserted between the upper and lower leg portions 63b and 63c, and the coupling head 63a protrudes outward from a tape side end edge of the fastener tape 61 at the element attaching portion 61a side.

In the slide fastener 50 of the third embodiment, the fastener tape 61 includes a tape extension portion 65 that extends outward more than the connecting portion 63d of the fastener element 63 so as to be exposed to the outside when the slide fastener 50 is observed from the fastener element 63 side (front side). That is, in the slide fastener 50 of the third embodiment, when the position of an end edge of the fastener element 63 at the connecting portion 63d side in relation to the horizontal direction of the slide fastener 50 is used as a reference position, the dimension in the tape width direction of the tape body portion 61b is set so that an extension length X from the reference position to the tape end edge of the fastener tape 61 at the tape body portion 61b side satisfies a range of X>0 mm.

By setting the extension length X from the reference position to the tape edge to satisfy the range of X>0 mm in this manner, it is possible to provide the tape extension portion 65 to the left and right fastener tapes 61. In this manner, in manufacturing of the slide fastener 50, for example, when a sewing process of sewing the fastener element 63 to be attached to the fastener tape 61, a dying process of the fastener tape 61, and the like are performed, it is possible to reliably put the tape extension portion 65 of the fastener tape 61 so as to be placed between upper and lower rollers. Thus, it is possible to stably perform a predetermined process on the fastener chain while preventing flipping over or bending of the fastener tape 61.

Moreover, in the slide fastener 50 of the third embodiment, a dimension in the tape width direction of the tape extension portion 65 of the fastener tape 61 is restricted to 6 mm or smaller. That is, the dimension in the tape width direction of the tape body portion 61b is set so that the extension length X from the reference position to the tape end edge of the fastener tape 61 at the tape body portion 61b side satisfies the range of 0 mm<X≦6 mm.

Further, in the slide fastener 50 of the third embodiment, the fastener tape 61 has an ear portion 66 disposed in a tape side edge portion at the tape body portion 61b side, and the warp thread disposed in the ear portion 66 has tensile strength higher than that of the warp thread disposed in portions other than the ear portion 66 of the tape body portion 61b. In this case, six warp threads having high tensile strength are disposed in the ear portion 66. In this way, it is possible to stabilize the form of the fastener tape 61 without causing a bias in the fastener tape 61.

In the slide fastener 50 of the third embodiment having the above-described configuration, the extension length X of the tape extension portion 65 of the fastener tape 61 is restricted to 6 mm or smaller. Thus, even when the slide fastener 50 is curved in the tape width direction, it is possible to effectively suppress the tape extension portion 65 of the fastener tape 61 from partially floating or sinking and the occurrence of wavy wrinkles. Therefore, it is possible to maintain the fastener tape 61 in an approximately flat form.

Therefore, when the slide fastener 50 of the third embodiment is sewn to a fastener-attached product such as automobile seat covers in a state where the slide fastener 50 is curved in the tape width direction of the fastener tape 61, it is possible to stably sew the tape body portion 61b of the fastener tape 61 and the fastener-attached product together.

Further, even after the slide fastener 50 of the third embodiment is sewn to be attached to the fastener-attached product in a state where the slide fastener 50 is curved in the tape width direction of the fastener tape 61, it is possible to prevent the occurrence of partial floating, sinking, or wavy wrinkles in the fastener tape 61 or to make them small so as not to be noticeable even when partial floating, sinking, or wavy wrinkles occur. Therefore, it is possible to prevent deterioration of the quality of external appearance of the fastener-attached product to which the slide fastener 50 is sewn and attached and to prevent deterioration of the sliding property of the slider 53.

DESCRIPTION OF REFERENCE NUMERALS

• • 10: CONCEALED SLIDE FASTENER
  • 11: TOP STOP
  • 12: BOTTOM STOP
  • 13: CONCEALED SLIDE FASTENER SLIDER
  • 20: FASTENER STRINGER
  • 21: FASTENER TAPE
  • 21a: ELEMENT ATTACHING PORTION
  • 21b: TAPE BENT PORTION
  • 21c: TAPE BODY PORTION
  • 22: ELEMENT ROW
  • 23: FASTENER ELEMENT
  • 23a: COUPLING HEAD
  • 23b: UPPER LEG PORTION
  • 23c: LOWER LEG PORTION
  • 23d: CONNECTING PORTION
  • 24a: GROUND WEFT THREAD
  • 24b: GROUND WARP THREAD
  • 24c: UPPER FIXING WARP THREAD
  • 24d: LOWER FIXING WARP THREAD
  • 24e: FASTENING WARP THREAD
  • 24f: POSITIONING WARP THREAD
  • 25: TAPE EXTENSION PORTION
  • 26: EAR PORTION
  • 30: CONCEALED SLIDE FASTENER
  • 40: FASTENER STRINGER
  • 41: FASTENER TAPE
  • 41a: ELEMENT ATTACHING PORTION
  • 41b: TAPE BENT PORTION
  • 41c: TAPE BODY PORTION
  • 43: FASTENER ELEMENT
  • 43a: COUPLING HEAD
  • 43b: UPPER LEG PORTION
  • 43c: LOWER LEG PORTION
  • 43d: CONNECTING PORTION
  • 45: TAPE EXTENSION PORTION
  • 46: EAR PORTION
  • 47: SEWING THREAD
  • 48: CORE THREAD
  • 50: SLIDE FASTENER
  • 51: TOP STOP
  • 52: BOTTOM STOP
  • 53: SLIDER
  • 60: FASTENER STRINGER
  • 61: FASTENER TAPE
  • 61a: ELEMENT ATTACHING PORTION
  • 61b: TAPE BODY PORTION
  • 62: ELEMENT ROW
  • 63: FASTENER ELEMENT
  • 63a: COUPLING HEAD
  • 63b: UPPER LEG PORTION
  • 63c: LOWER LEG PORTION
  • 63d: CONNECTING PORTION
  • 65: TAPE EXTENSION PORTION
  • 66: EAR PORTION
  • 67: SEWING THREAD
  • 68: CORE THREAD
  • X: EXTENSION LENGTH

Claims

1. A fastener stringer for a slide fastener, including a fastener tape and a continuous fastener element attached to one side edge portion of the fastener tape, and in which the fastener element includes a coupling head, upper and lower leg portions extending in a tape width direction from the coupling head, and a connecting portion that connects the adjacent fastener elements, and the other side edge portion of the fastener tape extends beyond an edge of the fastener element closer to the connecting portion, wherein:

an extension length of the fastener tape in the tape width direction from a position of an end edge at the connecting portion side of the fastener element to a tape end edge of the fastener tape at the other side edge side is restricted to be smaller than 12 mm.

2. The fastener stringer according to claim 1, wherein the extension length is restricted to 10 mm or smaller.

3. The fastener stringer according to claim 2, wherein the extension length is restricted to 6 mm or smaller.

4. The fastener stringer according to claim 1, wherein:

the fastener tape is formed of fabrics and includes a tape body portion and an element attaching portion disposed closer to one side edge side of the tape body portion;

an ear portion is disposed in the other side edge portion of the tape body portion; and

warp threads disposed in the ear portion have tensile strength higher than that of warp threads disposed in portions other than the ear portion of the tape body portion.

5. The fastener stringer according to claim 4, wherein four to six warp threads are disposed in the ear portion.

6. The fastener stringer according to claim 1, wherein:

the fastener tape includes a tape body portion, a tape bent portion extending in the tape width direction from one side edge of the tape body portion so as to be bent in an U-shape, and an element attaching portion which extends further from the tape bent portion and to which the fastener element is attached; and

the fastener element is attached to the element attaching portion of the fastener tape in such a manner that the coupling head protrudes outward from the tape bent portion.

7. The fastener stringer according to claim 6, wherein:

the fastener element is woven into the element attaching portion simultaneously with weaving of the fastener tape.

8. The fastener stringer according to claim 1, wherein:

the fastener tape includes a tape body portion and an element attaching portion which extends in the tape width direction from one side edge of the tape body portion and to which the fastener element is attached; and

the fastener element is attached to the element attaching portion of the fastener tape in such a manner that the coupling head protrudes outward from a tape side edge closer to the element attaching portion.

9. A slide fastener including the fastener stringer according to claim 1.