Waterproof Stringer and Waterproof Fastener

The present disclosure relates to waterproof stringer and waterproof fastener.

It has been known to laminate a waterproof film onto a base fabric of fastener tape via an adhesive so as to impart waterproofness to the fastener tape as disclosed in PTL1. In the PTL1, polyurethane film is employed as the waterproof film, and a water-base polyurethane adhesive is employed as the adhesive. Similar to the PTL1, PTL2 relates to a slide fastener with waterproofness, and particularly discloses that an element-attachment portion of fastener tape consists of a 1/1 weave for a purpose of reducing a sliding resistance associated with opening and closing operations of the slide fastener. Paragraph 0025 of PTL2 describes that, a defect may be caused in a tightening thread for sewing a coil-like element in a situation where the element-attachment portion consists of a twill weave. Para. 0053 of PTL2 discloses that element-attachment portion and tape main portion consist of a twill weave. PTLs 3 and 4 disclose a wide varieties of weaves of fastener tapes.

In a situation where a waterproof film is laminated, on the opposite side of a coil-like element, to a ground structure of fastener tape on which the coil-like element is sewn, an appearance (look) of waterproof stringer may be deteriorated due to gaps formed between the waterproof film and the ground structure. For example, the adhesive incompletely fills the gaps where air remains to effect whitish appearance. The present inventors have intensively analyzed a relationship between the ground structure of fastener tape and a machine-sewn thread for a purpose of improved appearance of such waterproof stringers, until arriving at the following present inventions. It should be noted that even if an amount of adhesive were simply increased, this may result in increased hardness and reduced softness of the waterproof stringer.

A waterproof stringer according to an aspect of the present disclosure includes: a fastener tape woven from at least one weft thread and plural warp threads: a coil-like element sewn to the fastener tape by a machine-sewn thread so as to be placed on a tape bottom surface of the fastener tape; and a waterproof film laminated onto a tape top surface of the fastener tape on an opposite side of the coil-like element. The fastener tape includes: an element-attachment portion overlapping the coil-like element in a thickness direction of the fastener tape; and a tape main portion which is a remainder other than the element-attachment portion. The machine-sewn thread including plural floating portions each floating over the tape top surface and floating out from a ground structure of the fastener tape, each floating portion having two sinking ends which sink toward the tape bottom surface of the fastener tape as being entrained by a sewing-machine needle which pierces the ground structure of the fastener tape. The ground structure of the fastener tape includes a twill weave that is formed to cross a boundary between the element-attachment portion and the tape main portion. The floating portion extends to cross a rib and/or a groove between adjacent ribs of the twill weave in the element-attachment portion. The waterproof stringer has a plurality of hollows each formed between the floating portions and corresponding to a piercing position of the sewing-machine needle. The plurality of hollows includes one hollow positioned between adjacent ones of the ribs or plural hollows each positioned between adjacent ones of the ribs.

In some embodiments, the plural floating portions are arranged linearly, and the ribs extend along diagonal straight lines relative to an arrangement direction of the floating portions. An angle between the arrangement direction of the floating portions and an extending direction of the rib may be in a range between 10° and 30°. Alternatively, the angle may be in a range between 15° and 30° or between 20° and 30°

In some embodiments, each hollow of the plurality of hollows is observed as a hollow having an area of 0.2 mmor less in an image showing unevenness of the tape top surface of the fastener tape.

In some embodiments, an average area of the plurality of hollows is in a range between 0.1 mmand 0.2 mmin an image showing unevenness of the tape top surface of the fastener tape.

In some embodiments, a median value in area distribution of the plurality of hollows is in a range between 0.3 mmand 0.6 mmin an image showing unevenness of the tape top surface of the fastener tape.

In some embodiments, the plurality of hollows includes at least one hollow surrounded by the floating portions and the ribs, the at least one hollow being observed in an image showing unevenness of the tape top surface of the fastener tape.

In some embodiments, the twill weave is formed across an entire area of the element-attachment portion.

In some embodiments, the twill weave is formed across an entire area of the tape main portion except for a tape edge region of the tape main portion, the tape edge region being located on an opposite side of the element-attachment portion.

In some embodiments, the twill weave includes plural sub-zones with different extending directions of the ribs.

In some embodiments, the machine-sewn thread is thicker than a width of the warp thread of the twill weave.

In some embodiments, conditions of (a) and/or (b) is satisfied: (a) an arrangement direction of the floating portions matches or is parallel to an elongation direction of the waterproof stringer; and (b) the coil element is sewn onto the fastener tape by double chain stitch, and the machine-sewn thread is a needle thread of the double chain stitch.

In some embodiments, each hollow of the plurality of hollows is filled at least partially by an adhesive used for the lamination of the waterproof film onto the fastener tape.

A waterproof fastener according to an aspect of the present disclosure includes: a pair of waterproof stringer each being the waterproof stringer of any one of above-described ones; and a slider for engaging and disengaging the pair of waterproof stringers.

According to an aspect of the present disclosure, a waterproof stringer may have improved appearance.

Hereinafter, various embodiments and features would be discussed with reference to drawings. A skilled person would be able to combine respective embodiments and/or respective features without requiring excess description, and would appreciate synergistic effects of such combinations. Overlapping descriptions among the embodiments would be basically omitted. Referenced drawings aim mainly for describing inventions and are simplified for the sake of convenience of preparation of drawings. The respective features should be appreciated as universal features not only effective to the waterproof stringer and method of producing the same presently illustrated but also effective to other various waterproof stringers and method of producing the same not illustrated herein.

In the present disclosure, a direction of movement of sliderfor opening and closing a waterproof fasteneris assumed as a front-rear direction (see double-headed arrow FB in). A direction parallel to a width direction of the waterproof fasteneris assumed as a left-right direction (see double-headed arrow LR in). A direction parallel to a thickness direction of the waterproof fasteneris assumed as an up-down direction. Note that, the up-down direction is orthogonal to both front-rear and left-right directions. The up-down direction should not necessarily be a vertical direction (gravity direction). For example, when the waterproof fasteneris orientated such that its elongation direction matches the vertical direction, the up-down direction of the waterproof fasteneris included in a horizontal direction (which is orthogonal to the vertical direction). As such, directions referred in the present specification are irrelevant to the vertical direction. Note that, as described in the followings, directions other than the front-rear direction, the left-right direction, the up-down direction may be referred.

The waterproof fasteneris a flexible elongated part elongated in the front-rear direction with a predetermined width in the left-right direction, and has a pair of left and right waterproof stringers,, and a sliderfor engaging and disengaging the waterproof stringers,. Likewise the waterproof fastener, the waterproof stringers,are flexible elongated parts too elongated in the front-rear direction with a constant width in the left-right direction. As the slidermoves frontward, the left and right waterproof stringer,(particularly, coil-like element,described below) are engaged, and a waterproof seal is formed based on abutting contact between opposed side-edgesof the waterproof films,described in hereinafter (see). As the slidermoves rearward, the left and right waterproof stringer,(particularly, the coil-like element,described below) are disengaged, and the opposed side-edges of the waterproof film,are also released from the abutting contact. Note that the abutting contact between the side-edgesof the waterproof films,does not present a high endurance against water pressure, but some level of waterproofness may be achievable. It may be possible to omit the abutting contact between the side-edgesof the waterproof films,, resulting in reduced waterproofness in this case.

The waterproof stringer,has a fastener tape,: a coil-like element,sewn onto the fastener tape,by a machine-sewn threadso as to be placed on a tape bottom surfaceof the fastener tape,; and a waterproof film,laminated onto a tape top surfaceof the fastener tape,on the opposite side of the coil-like element,. The waterproof stringer,has a hardness and softness in accordance with the stacking of the waterproof film,and the fastener tape,. The waterproof film,supports the fastener tape,, thus allowing a selection from a wide variety of ground structures of the fastener tape,. In some cases, a weave structure is selected which enhances softness of the fastener tape,, and this enhanced softness of the fastener tape,may be compensated by the hardness of the waterproof film,

The fastener tape,includes an element-attachment portionon which the coil-like element,is placed and overlaps the coil-like element,in the thickness direction of the fastener tape,; and a tape main portionwhich is a remainder other than the element-attachment portion. The element-attachment portionmay be narrower than the tape main portion. Boundary Pbetween the element-attachment portionand the tape main portionmay be defined in a plane that is parallel to the central plane CP of the waterproof fastenerand in contact with a return portionof the coil-like element,described hereinbelow. The central plane CP of the waterproof fastenerincludes an axial line defining a movement path for the sliderand is orthogonal to the width direction (i.e. the left-right direction) of the waterproof fastener. As the left and right coil-like elements,are engaged, a slit is formed between the opposed side-edgesof the left and right fastener tapes,. This slit is fully or partially covered by the waterproof films,, thus some level of waterproofness is achieved.

The fastener tape,is a woven fabric with higher softness woven from at least one weft threadand plural warp threads. Automatic loom may be used for weaving the fastener tape,. The weft threadand the warp threadsare a thread (e.g. monofilament thread or multifilament thread) with desired characteristic (denier value, color). Before weaving the fastener tape,, the weft threadand the warp threadsmay be dyed, or the fastener tape,may be dyed after they are woven. The weft threadmay be interlaced with the warp threadsfor each bundle of two weft-thread portions thereof being pulled together in the weft direction, but no limitation should be placed on this aspect. It may be possible that the weft threadis interlaced by the warp threadsfor each single weft thread portion thereof. Note that, the fastener tape,is a woven fabric woven from the weft threadand the warp threadsdescribed above, thus allowing water permeation and penetration through the threads themselves and through the apertures between the threads.

In, the tape bottom surfaceand the tape top surfaceof the fastener tape,are depicted as a flat surface, but they are non-flat surfaces actually. Every or each warp threadincluded in the fastener tape,repeats crossing above the weft thread(i.e. on the side of the tape top surface) and crossing beneath the weft thread(i.e. on the side of the tape bottom surface). Floating and sinking of each warp threadas noted above spread in the width direction of the fastener tape,, thus allowing the tape bottom surfaceand the tape top surfaceto have two-dimensionally distributed unevenness.

The coil-like element,typically consists of a wounded coil-like monofilament, and includes a series of units Ueach consisting of upper leg, lower leg, engagement head, and return portion(See). The upper legand the lower legextend in the width direction of the fastener tape,, and have outward and inward ends regarding the fastener tape. The engagement headextends in the up-down direction so as to interconnect the outward ends of the upper and lower legsandregarding the fastener tape. The return portionextends and curves so as to interconnect the inward ends of the lower and upper legsandbetween the adjacent units U. Note that the outward regarding the fastener tape indicates, regarding one fastener tape, a direction directed from a point positioned on the tape surface of the fastener tape to a point positioned externally of the tape surface of the fastener tape, and may cross (e.g. be orthogonal to) the opposed side-edgein some cases. Note that the inward regarding the fastener tape indicates, regarding one fastener tape, a direction directed from a point positioned externally of the tape surface of the fastener tape to a point positioned on the tape surface of the fastener tape, and may cross (e.g. be orthogonal to) the opposed side-edgein some cases. The engagement headhas a meshing portion (biting portion) molded to have a wider width in the front-rear direction through plastic deformation of the monofilament, allowing the engagement of the left and right coil-like elements,

The coil-like element,may be variously sewn to the fastener tape,by the machine-sewn thread. Typical situations including the depicted example, the coil-like element,is sewn to the fastener tape,by double chain stitch or lock stitch based on operation of the sewing machine. The sewing-machine needle of the sewing machine reciprocates in the up-down direction so as to penetrate through the fastener tape,, and a looper of the sewing machine moves along the front-rear direction so that a looper thread is entangled with a lower loop of the needle thread. Moreover, a feeding mechanism of the sewing machine continuously or intermittently feeds the fastener tape,and the coil-like element,in the front-rear direction. In a case of double chain stitch, two sewing-machine needles are preferably used to form two lines of stitches on the tape top surface, but the number of sewing-machine needle would be changed as desired.

As the sewing-machine needle pierces the fastener tape,, the ground structure of the fastener tape,is deformed, e.g. the weft threadthereof slightly moves (i.e. escapes) in the front-rear direction (feeding direction) and/or the warp threadthereof slightly moves (i.e. escapes) in the tape width direction (the left-right direction). The feeding speed of the sewing machine may be set to be constant, and the sewing-machine needle may pierce the fastener tape,at a predetermined interval along the elongation direction of the fastener tape,. It should be noted that the piercing positions of the sewing-machine needle may fluctuate slightly in accordance with feeding accuracy of the sewing machine, slipping and tape softness and the like. Note that, in an exemplary example, the sewing-machine needle pierces into and is pulled out from the fastener tape,which is stationary during the transportation.

In the above-described case, the machine-sewn threadincludes at least two different threads such as the needle threadand the looper thread, and these threads are regularly entangled so that the coil-like element,is secured to the fastener tape,. The needle threadincludes a plurality of floating portionseach floating over the tape top surfaceand floating out from the ground structure of the fastener tape,(see). Each floating portionhas two sinking ends,which sink toward the tape bottom surfaceof the fastener tape,as being entrained by the sewing-machine needlewhich pierces the ground structure of the fastener tape,. Typically, the plurality of floating portionsmay be arranged in a direction matching or parallel to the elongation direction of the waterproof stringer,(i.e. linearly), but should not be limited to this. The waterproof stringer,has a plurality of hollowseach interposed between the floating portionsand corresponding to the piercing positions of the sewing-machine needle. More detail discussion on the hollowmay follow hereinbelow.

Additionally to the floating portionsdescribed above, the needle threadincludes a thread portionthat extends downward: a thread portionentangled with the looper thread; and a thread portionthat extends upward, for a purpose of interconnecting the sinking endand the sinking endof adjacent floating portions. That is, the needle threadis a meandering thread including a series of alternate upper and lower loops, the upper loop including the floating portionand the lower loop including the thread portion. Depicted is that the thread portionand the thread portionare in direct contact, but it should not be limited to this manner. Furthermore, the interlacing pointwhere the needle threadand the looper threadare entangled is positioned closer to the lower legthan the upper legin the up-down direction, but should not be limited to this.

The tension of the needle threadmay be adjusted by regulating the amount of feeding the needle threadfor each up-down motion of the sewing-machine needle, and this equally applies to the looper thread. In either way, the needle threadand the looper threadare entangled so that the needle threadand the looper threadwould have a prescribed tension or a tension within a prescribed range. As a result of this, the ground structure of the fastener tape,may be deformed due to the needle threaditself in addition to the piercing of the sewing-machine needle(escaping from the sewing-machine needle), e.g. its weft threadis pushed to displace (typically slightly) in the front-rear direction and/or its warp threadis pushed to displace (typically slightly) in the left-right direction. These local movement of the threads facilitates formation of the hollowsdescribed below. Note that, it is not a requisite to allow the needle threadand the looper threadto be entangled by moving the sewing-machine needledownward for every unit Uof the coil-like element. For example, the sewing-machine needlecan be moved downward for every two or three units Uso as to allow the needle threadand the looper threadto be entangled.

Typically, the waterproof film,is a film having a prescribed thickness and made of thermoplastic resin. As the thermoplastic resin, at least one selected from a group consisting of Polyurethane, Polyester, Polyethylene, Polypropylene and Polyvinyl alcohol may be employed, for example. The waterproof film,may be laminated onto the fastener tape,via an adhesive exemplarily, but it may be laminated onto the fastener tape,through surface-melting or coating or the like. That is, methods other than the adhesive may be employed for a purpose of the lamination of the waterproof film,onto the fastener tape,. In a preferred example, the waterproof film includes polyurethane, and the adhesive includes water-based polyurethane adhesive as presented in PTL 1 (the PTL is herein incorporated by reference in its entirety).

Referring to, the ground structure of the fastener tape,includes a twill weaveformed to cross the boundary Pbetween the element-attachment portionand the tape main portion. Preferably, the twill weaveincludes a plurality of ribsextending to cross the boundary Pbetween the element-attachment portionand the tape main portion. This allows that difference becomes less apparent between the both sides of the boundary Pin connection to the laminated condition between the ground structure and the waterproof film,, thus enhancing uniformity of appearance and/or degree of surface flatness of the waterproof stringer,. The surface flatness may be determined by calculating a surface roughness of the waterproof film,

In more detail, the twill weaveincludes a first zoneformed to cross the boundary Pbetween the element-attachment portionand the tape main portion, and a second zoneof the remainder. The first zoneincludes a plurality of ribsextending to cross the boundary P. The second zoneincludes a tape edge regionsituated on the opposite side of the element-attachment portionof the tape main portion, and a plurality of sub-zones,with different extending directions of the ribs(e.g. opposite directions). The tape edge regionconsists of a plain weave, but other type of weaves may be employed. In the sub-zone, the ribsextend diagonally so as to be away from the element-attachment portionas extending along the warp direction. In the sub-zone, the ribsextend diagonally so as to be close to the element-attachment portionas extending along the warp direction. That is, the sub-zones,have the ribswhich are in a relationship of mirror image. As such, the softness and the like of the ground structure may be adjustable based on the sub-zones with different extending directions of the ribs. Note that, the twill weave may be used for a purpose of obtaining a constant hardness while maintaining a higher softness.

In some cases, the entire area of the element-attachment portionconsists of the twill weave, but should not be limited to this. Additionally or alternatively, the entire area of the tape main portionexcept for the tape edge regionconsists of the twill weave, but should not be limited to this. Larger area of the twill weave may ensure that the machine-sewn thread is more reliably pierced into the twill weave and simultaneously facilitate higher surface flatness of the waterproof stringer,(in turn, improved appearance thereof) as would be appreciated based on comparison between. The fastener tape,shown inconsists of a twill weave in its entire area except for the tape edge region. The fastener tape shown indoes not include a twill weave in its tape main portion and thus, as shown in, the surface of the waterproof stringer has noticeable unevenness when comparing it with one shown inand its flatness is reduced.

shows a weave structure on the side of the tape top surfaceof the fastener tape,. In the diagram of weave structure of, the grid cells are arranged two-dimensionally in the row and column directions. The row direction matches the weft direction the weft thread extends, and the column direction matches the warp direction the warp thread extends. Note that in cases where the warp thread crosses every two weft thread portions pulled together in the tape width direction, each grid cell includes the two weft-thread portions. The number of warp thread included in each grid cell may be one, but should not be limited to this. The hatched rectangular grid cells indicate the floating portionsof the warp threads. The ribsare formed by the floating portionsof the warp threadswhich are continuously arranged in a diagonal direction relative to the weft thread. The extending direction Dof the ribmay be defined by interconnecting, by a straight line, central points of the respective floating portionsin the front-rear direction. Groovesmay be formed between the adjacent ribsin the warp direction which extend diagonally similar to the ribs.

In, parallel two dotted lines represent the needle threadsof a prescribed thickness, and dotted circles represent piercing positions of the sewing-machine needle. There is the floating portionof the needle threadbetween the dotted circles. The piercing positions of the sewing-machine needleare assumed to be positioned within the dotted circles, but may slightly deviate from the dotted circles. In the view of weave structure of, the floating portionextends to cross the rib(similarly the groovebetween the ribs) of the twill weave in the element-attachment portion. Moreover, piercing positions of the sewing-machine needleare located between the adjacent ribsalong the warp direction (see P-Pand the like in, for example), and the hollowswould be positioned between the adjacent ribs. The hollowmay have a reduced spatial size (capacity) due to the bulging of the rib, and the hollowmay be formed to have a smaller area when observed from the above. In contrast, in cases where the element-attachment portionconsists of plain weave, there is no rib itself. Therefore, the hollowwould never be downsized and reduced into a smaller area by the rib. In a case where the element-attachment portionconsists of rib weave (rep), the spatial size of the hollowwould be enlarged as the weft thread easily moves in the warp direction when tension is applied to the machine-sewn threadfor a purpose of securement of the coil-like element. Therefore, similar effects as those of the present embodiment would not be obtainable. Note that, the above-noted hollowsmay be observed as white-opaque areas when observed from the side of the top surface of the waterproof chain as shown in.

In the present embodiment, the waterproof stringer,has the plurality of hollowseach being formed between the floating portionsand corresponding to the piercing position of the sewing-machine needle, and the plurality of hollowsincludes one hollowpositioned between the adjacent ones of the ribsor two or more hollowseach positioned between the adjacent ones of the ribs(typically plural hollowseach positioned between the adjacent ones of the ribs). According to this aspect, the hollowmay be formed to have smaller size and smaller area between the floating portionsdue to the ribsof the ground structure of the fastener tape,. Accordingly, it may be suppressed that air remains in the hollowregardless of the use and non-use of adhesive when the waterproof film,is laminated onto the tape top surfaceof the fastener tape,which otherwise results in the deteriorated appearance of the waterproof stringer,(e.g. whitish appearance at the spot of the hollow). In this way, it may be avoided or suppressed that the yield rate is reduced due to non-sophisticated appearance of the waterproof stringer,and at the same time, a quality appearance be added to the waterproof stringer,. As an additional or alternative effect, the machine-sewn threadextends along the rib(i.e. does not extend so as to be orthogonal to the rib), thus reducing an extent of floating appearance of the machine-sewn threadover the ground structure. As an additional or alternative effect, the hollowis formed to have smaller area as described above, allowing use of thicker machine-sewn thread(i.e. with greater denier) which otherwise results in the hollowhaving a greater area. The use of thicker machine-sewn threadmay enhance the attachment strength of a coil-like element or allow attachment of a coil-like element having a greater size. In some cases, the machine-sewn threadis a thread that is bulky relative to the width of the warp thread of the above-described twill weave, preferably a twisted multi-filament thread. Typically, the machine-sewn threadis a twisted multi-filament thread having a substantially circular shape in the cross section. Note that the ribswhich contribute to the smaller size and smaller area of the hollowmay be positioned on the both sides of the hollowin the tape width direction (weft direction).

Further discussion follows on various effects with reference to.is a photograph showing the top surface of waterproof chain where unevenness can be observed which is in accordance with floating portions of the machine-sewn threads on left and right sides of the chain central plane CP.is an image, observed and captured by 3D shape measuring machine (one-shot 3D shape measuring machine (VR-3200) produced by Keyence), of the tape top surface of fastener tape before lamination of the waterproof film in which depth is indicated by color difference (shading in a black-and-white image). Comparative example is referred here for facilitated understanding. In the comparative example, an element-attachment portion of fastener tape includes the weave structure of(i.e. does not include a twill weave). In the comparative example, a tape main portion also does not include a twill weave.is a photograph showing a top surface of waterproof chain according to the comparative example.is an image, observed and captured by 3D shape measuring machine (the same one as the working example), of the tape top surface of fastener tape before lamination of the waterproof film according to the comparative example in which depth is indicated by color difference (shading in a black-and-white image). Note that in both cases of the working and comparative examples, the waterproof film,is laminated onto the fastener tape,via an adhesive. Moreover, the working and comparative examples use the same material except for the difference in the weave structure of the fastener tape; and they are produced through the same production process and are observed under the same condition and by the same device. Note that in the both cases of the working and comparative examples, machine-sewn threads (the needle thread and the looper thread) are used which are thicker than the warp thread and the weft thread.

In bothand, ridges are observed which are in accordance with the floating portions of the needle thread on the both sides of the central plane CP of the waterproof chain. In the, white-opaque areas are formed around a number of floating portions. In, not only at the intervening spots between the floating portions, there are even slightly longer white-opaque areas each of which is formed to extend along the floating portion. In contrast, there are slight white-opaque areas at the intervening spots between the floating portions inbut, these are smaller in area relative to those shown in. Moreover, no slightly longer white-opaque area extending along the floating portion is formed in.

In bothand, the hollowsformed between the floating portionsare observable. Inand, dotted lines are drawn on the respective contours of the floating portionswhich are adjacent in the warp direction, and a solid line is drawn on a contour of the hollowbetween those floating portions. The dotted and solid lines are not drawn for every floating portion and ever hollow, but would be similarly assumable. As would be understood by comparingand, an area of the hollowobserved inis smaller than an area of the hollowobserved in. Average of area may be used for the comparison of area.

In more detail, in either of the working and comparative examples, two lines of stitches L,L(each consisting of a series of floating portions) are formed in each of the waterproof stringers,. In, each hollowis formed between adjacent floating portionsof the respective line of stitches L,L. In, a smaller number of hollowsare formed on the line of stitches L, and a greater number of larger sized hollowsare formed on the line of stitches L. In, the number and area of hollow may be suppressed on the line of stitches Lon one side, but the greater number of hollows having a larger area are formed on the line of stitches Lon the other side, resulting in deteriorated appearance of the waterproof stringer as a whole. In the working example, the hollowshaving a smaller area are formed on both lines of stitches L,L, resulting in the improvement of appearance of waterproof stringer. There is an outstanding practical advantage of improved appearance of waterproof stringer based on the modification of weave structure of fastener tape without changing the amount of adhesive. Use of increased amount of adhesive may potentially result in increased hardness of the waterproof stringer.

Preferably, the ribmay extend along diagonal straight lines relative to an arrangement direction of the floating portions(i.e. extending direction of the stitches), and an angle θ between the arrangement direction of the floating portionsand the extending direction of the rib(i.e. D) may be any angle in a range between 10° and 30° (i.e. an angle at 10°, 30° or intermediate value). Note that the intermediate value should not be limited to a natural number such as 11°, 12°, . . . 28°, 29°. In this case, the angular difference between the floating portionand the ribbecomes lesser (i.e. both aligned into near-parallel relationship), and the surface flatness of the waterproof stringer,may be enhanced so that the appearance is improved. Reduction in the angle of the ribmay cause corresponding reduction in the softness of the fastener tape (i.e. the fastener tape may have increased hardness), and this may potentially cause increased sliding resistance of the slider while it is in contact with the fastener tape. Therefore, the above-described angle θ is preferably 15° or more, or 20° or more. Advantageously, the angle θ between the arrangement direction of the floating portionsand the extending direction of the ribis equal to an angle in a range between 15° and 30° or in a range between 20° and 30°.

The number of the warp threads per a unit width (e.g. 4 mm) would be suitably set for a purpose of setting an angle of the above-described rib. In some cases, 10 to 20 preferably 14 to 18 warp threads per the unit width of 4 mm may be introduced in the element-attachment portion.

The following features would be appreciated from the image ofobtained by the 3D shape measuring machine (specifically, the image showing unevenness of the tape top surfaceof the fastener tape,before lamination of the waterproof film,). Of course, similar optical observation can be done after peeling off the waterproof film,by using a suitable solvent even after the lamination of the waterproof film,. Similar optical observation can be done without peeling off the waterproof film,depending on a type and setting of the 3D shape measuring machine.

Advantageously, every hollowis filled at least partially by the adhesive used for the lamination of the waterproof film,onto the fastener tape,, but should not be limited to this. It is envisioned that some hollows of a multiplicity of hollowsare not filled by the adhesive at all. For example, there are situations where the waterproof stringer, which is an intermediate product with respect to production of waterproof fastener, is partially removed for a purpose of attaching the slider. In such removed portion, the adhesive may not be applied or lesser amount of adhesive is applied, resulting in locally deteriorated appearance of the waterproof stringer.

Finally, a method of production of waterproof stringer would be discussed briefly.is a flowchart showing a production process of the waterproof stringer.is a schematic process diagram in which a waterproof film is laminated onto waterproof chain.is a schematic process diagram in which the waterproof film laminated onto the waterproof chain is cut by a cutter.

Firstly, the fastener tape is woven from the weft thread and the warp threads (S). Advantageously, its entire structure consists of the twill weave except for the tape edge region of the tape main portion. The twill weave may include plural zones including ribs extending in different directions as noted above. Next, the coil-like element is sewn to the fastener tape (S). For this purpose, an industrial sewing machine may be used. The coil-like element may be sewn to the fastener tape such by double chain stitch or lock stitch or the like. Next, the waterproof film is laminated onto the fastener tape (S). The adhesive may be applied as a layer onto the tape top surface of the fastener tape before the lamination. A greater number of hollows may be formed to have a smaller area owing to the ribs, and would be more sufficiently filled by the adhesive. The same effect may be obtained when the waterproof film is melted at its surface for attachment.

As shown inand, the waterproof film is laminated onto the fastener chain in which the waterproof stringers,are engaged, followed by cutting the waterproof film by a cutterat a position over the slit between the left and right fastener tapes,

Based on the above teachings, those skilled in the art may make various changes to each embodiment and each feature. The codes incorporated in the claims are for reference only and should not be referred to for a purpose of limiting the scope of claims.