SLIDE FASTENER WITH SEALING FUNCTION

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based on and claims priority under 35 USC § 119 from German Patent Application No. 102024122093.7 filed on Aug. 2, 2024, the contents of which are incorporated herein by reference.

TECHNICAL FIELD

The present invention is related to a slide fastener including a pair of fastener stringers, each of the pair of fastener stringers including a fastener tape and a fastener element row attached to each of opposing side portions of the pair of fastener stringers; a slider provided slidably at the fastener element row for engagement and disengagement of opposing fastener elements, the slider including an upper blade, a lower blade and a guide column connecting the upper and lower blades in an up-down direction, the upper and lower blades and the guide column defining a boundary of a guide channel for the fastener elements. Each of the pair of fastener stringers includes a seal part adhered to a tape surface portion of the fastener tape and extending over an element surface portion of each of the fastener elements of each of the pair of fastener stringers, the seal part being in sealing abutment when the slide fastener is in an engaged state.

BACKGROUND

A related slide fastener is disclosed in the related art, for example, in CN203262436U, U.S. Pat. No. 10,080,405B2 and U.S. Pat. No. 9,474,341B2. The seal parts which are in sealing abutment in the engaged state of the slide fastener provide a sealing function to thereby prevent fluid from passing through the slide fastener. Thus, a slide fastener with a watertight or airtight property may be provided. Such slide fasteners have various applications, including clothes, tents, wetsuits, space suits, water tanks, etc.

The slide fasteners disclosed in the references cited above share the problem that the seal part extends over a surface portion of the fastener elements which faces one of the blades of the slider and may come into contact therewith when the slider moves along the fastener element rows to engage and disengage the fastener elements. As the slider is in general made of a harder material than the seal part, the seal part may be damaged by the contact with the blade of the slider and therefore the sealing function may be impaired.

To overcome this problem, EP1388302A1 discloses a slide fastener in which two seal parts are provided on facing edge portions of the fastener tapes distant from the blades of the slider. The seal parts compress against each other and against coupling portions of the fastener elements provided on the opposing fastener tape when the slide fastener is in the engaged state. Each fastener element includes an upper half provided on an upper tape surface of the fastener tape, a lower half provided on a lower tape surface of the fastener tape and a connecting portion connecting the upper and lower halves by passing through a hole provided in the fastener tape. The holes are, however, unfavorable as they require an additional manufacturing step, a fastener tape with a hole requires precise molding of the fastener elements at the position of the holes, and the holes may even be a source of leakage of fluid thereby impairing the sealing function of the slide fastener.

The holes in the fastener tape are avoided in the slide fastener disclosed in WO2022/043684A1. Each fastener element also includes upper and lower halves that are connected by a connecting portion. However, the connecting portion is arranged at an edge portion of the fastener tape outside the fastener tape. A groove extending in a tape length direction and facing the opposite tape is provided in a coupling portion of each fastener element. In the engaged state of the slide fastener, each coupling portion bites into a side portion of the opposing fastener tape thereby providing the sealing function. While this solution avoids the holes in the fastener tape, the fastener elements may not be fixed well on the fastener tape, in particular in a case where the fastener elements and the fastener tapes are made of different materials which do not adhere well to each other. To overcome this problem, an additional step may be required in the manufacturing of the slide fastener. For example, plasma treatment may be required to provide a sufficient fixation of the fastener elements on the fastener tape. This additional manufacturing step is however time-consuming and increases costs.

Due to these problems in the related art, it is therefore an object of the present invention to provide a slide fastener with a sealing function and which is robust and durable.

SUMMARY

According to one aspect of the present invention, a slide fastener includes: a pair of fastener stringers, each of the pair of fastener stringers including a fastener tape and a fastener element row attached to each of opposing side portions of the pair of fastener stringers; and a slider provided slidably at the fastener element row for engagement and disengagement of opposing fastener elements, the slider including an upper blade, a lower blade and a guide column connecting the upper and lower blades in an up-down direction, the upper and lower blades and the guide column defining a boundary of a guide channel for the fastener elements. Each of the pair of fastener stringer includes a seal part adhered to a tape surface portion of the fastener tape and extending over an element surface portion of each of the fastener elements of each of the pair of fastener stringers, the seal part being in sealing abutment when the slide fastener is in an engaged state. At least one of the fastener elements includes a protrusion that extends through an aperture of the seal part in the up-down direction to thereby keep the seal part distant from the boundary of the guide channel.

According to one aspect of the present invention, each of the fastener elements includes the protrusion that extends through the aperture of the seal part in the up-down direction to thereby keep the seal part distant from the boundary of the guide channel.

According to one aspect of the present invention, the fastener tape includes a base sheet which is coated with and/or impregnated by a plastic material which is impermeable to fluid.

According to one aspect of the present invention, the fastener elements are made from a first resin, the seal part is made from a second resin. The first resin is harder than the plastic material and the second resin.

According to one aspect of the present invention, the second resin is harder than the plastic material.

According to one aspect of the present invention, the first resin includes a polyamide resin, the plastic material includes a first polyurethane and the second resin includes a second polyurethane.

According to one aspect of the present invention, the at least one of the fastener elements includes an upper end surface facing in an up direction and being distant from an upper tape surface of the fastener tape in the up direction, an opposite lower end surface facing in a down direction and being distant from a lower tape surface of the fastener tape in the down direction. The protrusion protrudes from at least one of the upper and lower end surfaces.

According to one aspect of the present invention, the at least one of the fastener elements includes a side surface portion provided opposite to an edge portion of the fastener tape and configured to be in sliding engagement with the boundary of the guide channel to thereby guide the fastener elements towards each other for the engagement. The seal part extends over the fastener elements without extending over the side surface portion.

According to one aspect of the present invention, each of the fastener elements includes an upper portion provided on an upper tape surface of the fastener tape, a lower portion provided on a lower tape surface of the fastener tape, and a connecting portion connecting the upper and lower portions in the up-down direction and being provided outside the fastener tape at an edge portion thereof.

According to one aspect of the present invention, an edge portion of the fastener tape includes a core thread.

According to one aspect of the present invention, the upper portion includes an upper base portion provided on the upper tape surface of the fastener tape, the lower portion includes a lower base portion provided on the lower tape surface of the fastener tape, and at least one of the upper and lower portions includes a coupling portion extending from at least one of the upper and lower base portions towards the opposite fastener tape and configured to engage with an opposite coupling portion of an opposite fastener element provided on the opposite fastener tape.

According to one aspect of the present invention, in a plan view on at least one of upper and lower tape surfaces, a distance between the neighboring fastener elements increases from a tape inner portion towards an edge portion of the fastener tape.

According to one aspect of the present invention, the coupling portion is arranged in the up-down direction so as to include a center line of the fastener tape in the up-down direction.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a plan view of an upper surface of a fastener stringer of a slide fastener according to an embodiment of the present invention.

FIG. 2 is a plan view of a lower surface of the fastener stringer of FIG. 1.

FIG. 3 is a perspective view of a fastener element of the fastener stringer shown in FIG. 1.

FIG. 4 is a perspective view of one fastener element and a portion of the seal part of the fastener stringer according to the embodiment.

FIG. 5A is a side view of the fastener element and the portion of the seal part shown in FIG. 4 along the tape length direction.

FIG. 5B is a side view of the fastener element of FIG. 5A without the seal part.

FIG. 5C is a side view of the portion of the seal part shown in FIG. 5A.

FIG. 6A is a front view of the fastener element and the portion of the seal part shown in FIGS. 4 and 5A in the left direction.

FIG. 6B is a sectional view of the fastener element and the portion of the seal part along the line A-A shown in FIG. 6A.

FIG. 7 is the same sectional view as in FIG. 6B in which a slide fastener is moved over the fastener element.

FIG. 8 is a perspective view of the fastener stringer shown in FIG. 1, in which some of the fastener elements are removed for ease of representation.

FIG. 9A is a partial perspective view of an upper side of the slide fastener according to the embodiment of the present invention.

FIG. 9B is a partial perspective view of a lower side of the slide fastener according to the embodiment of the present invention.

DESCRIPTION OF EMBODIMENTS

FIG. 1 is a plan view of an upper surface of a fastener stringer 1 of a slide fastener 100 according to an embodiment of the present invention. The slide fastener 100, part of which is shown in FIGS. 9A and 9B, includes another fastener stringer 1 which is similar to the one shown in FIG. 1. The fastener stringer 1 includes a fastener tape 20 which is an elongated member which is long in a tape length direction. The tape length direction is also called a front-back (F-B) direction within this specification. The front (F) direction is directed upwards with respect to the paper plane, and the back (B) direction is directed downwards with respect to the paper plane of FIG. 1. The tape also defines a tape width direction which is perpendicular to the front-back direction. The tape width direction is also called a left-right (L-R) direction within this specification. The left (L) direction is directed leftwards with respect to the paper plane of FIG. 1, and the right (R) direction is directed rightwards with respect to the paper plane of FIG. 1. The fastener tape 20 also defines an up-down (U-D) direction which is perpendicular to the tape length direction and the tape width direction. The up (U) direction is a direction perpendicular to the paper plane of FIG. 1 and is directed towards the viewer of the figure, and the down (D) direction is directed in the opposite direction.

In the plan view of FIG. 1, an upper tape surface 21a of the fastener tape 20 is visible. The fastener tape 20 includes a side portion 22 to which a fastener element row 3 is attached. It can also be said that the fastener element row 3 is attached to each of opposing side portions of the pair of fastener stringers 1. The side portion 22 includes an edge portion 23 which is an outer boundary of the fastener tape 20. The edge portion 23 includes a core thread 24 which extends in the tape length direction and which has an increased width in the up-down direction compared to a tape inner portion 26 of the fastener tape 20 which is arranged inside the fastener tape surface. Due to the core thread 24, fastener elements 30 of the fastener stringer 1 are fixed more securely on the fastener tape 20 compared to a fastener stringer without the core thread 24.

The fastener element row 3 includes a plurality of fastener elements 30 which are arranged at a predetermined pitch in the tape length direction to the side portion 22. The shape of the fastener elements 30 will be explained in more detail below.

The fastener stringer 1 further includes a seal part 50 which is adhered to a tape surface portion 25 of the fastener tape 20 and which extends over an element surface portion 31 of each fastener element 30. Each fastener element 30 includes a protrusion 32 that extends through an aperture 51 of the seal part in the up-down direction. As it will be explained in more detail below with reference to FIG. 7, the extension of the protrusion 32 through the aperture 51 of the seal part 50 in the up-down direction is so as to keep the seal part 50 distant from the boundary of a guide channel of a slider.

The fastener stringer 1 may further include upper and lower stops (not shown) which are provided at front and back end portions of the fastener element row 3 in the front-back direction and which limit the movement of a slider 60 of the slide fastener (see FIGS. 9A, 9B) in the tape length direction.

FIG. 2 is a plan view of a lower tape surface 21b of the fastener tape 20 of the fastener stringer 1 shown in FIG. 1 which is a tape surface opposite to the upper tape surface 21a. The row 3 of fastener elements 30 is attached to the side portion 22 including the edge portion 23 which includes the core thread 24. As one may take from FIG. 2, the seal part 50 does not extend over the lower tape surface 21b and does also not extend over lower surfaces of the fastener elements 30.

In the following, the fastener element 30 and the seal part 50 will be described in more detail with reference to FIGS. 3 to 6B. FIG. 3 is a perspective view of the fastener element 30 of the fastener stringer 1 shown in FIG. 1. FIG. 4 is a perspective view of one fastener element 30 and a portion of the seal part 50 of the fastener stringer 1 according to the embodiment. FIG. 5A is a side view of the fastener element 30 and the portion of the seal part shown in FIG. 4 along the tape length direction. FIG. 5B is a side view of the fastener element 30 of FIG. 5A without the seal part 50. FIG. 5C is a side view of the portion of the seal part 50 shown in FIG. 5A. FIG. 6A is a front view of the fastener element 30 and the portion of the seal part 50 shown in FIG. 4 in the left direction. FIG. 6B is a sectional view of the fastener element 30 and the portion of the seal part 50 along the line A-A shown in FIG. 6A.

First, the fastener element 30 without the seal part 50 is described in more detail in particular with reference to FIGS. 1, 2, 3, 5B and 8. The fastener element 30 includes an upper portion 33a provided on the upper tape surface 21a of the fastener tape 20 (see for example FIG. 1), a lower portion 33b provided on the lower tape surface 21b of the fastener tape 20 (see for example FIG. 2) and a connecting portion 34 connecting the upper and lower portions 33a, 33b in the up-down direction and being provided outside the fastener tape 20 at the edge portion 23 of the fastener tape 20. The connecting portion 34 includes a first connecting portion 34a extending in the up-down direction to thereby connect the upper and lower portions 33a, 33b and a thickened part 34b which is integral with the first connecting portion 34a and which has a width in the tape width direction which increases in the down direction. The thickened part 34b reinforces the first connecting portion 34a. The upper portion 33a, the lower portion 33b and the connecting portion 34 define a boundary of a gripping portion 35 for gripping the fastener tape 20. The gripping portion 35 includes a first gripping portion 35a for gripping the core thread 24 and a second gripping portion 35b which is in contact with the upper and lower tape surfaces 21a, 21b of the fastener tape 20.

The upper portion 33a includes an upper end surface 36a which is facing upwards. The lower portion 33b includes a lower end surface 36b which is facing downwards. The upper portion 33a includes an upper base portion 37a provided on the upper tape surface 21a and in contact therewith. The lower portion 33b includes a lower base portion 37b provided on the lower tape surface 21b of the fastener tape 20 and in contact therewith. The lower portion 33b further includes a coupling portion 38 extending from the lower base portion 37b towards the opposite fastener tape (see FIGS. 9A and 9B) and configured for an engagement with an opposite coupling portion of an opposite fastener element provided on the opposite fastener tape. In the embodiment shown in the figures, the upper portion 33a is not provided with a coupling portion, however the invention is not limited to this. That is, the upper portion 33a may include the coupling portion 38 extending from the upper base portion 37a. The coupling portion 38 is arranged in the up-down direction so as to include a center line of the fastener tape in the up-down direction.

The fastener element 30 further includes a protrusion 32 protruding from the upper end surface 36a of the upper portion 33a in the up-down direction. However, the protrusion 32 may protrude from the lower end surface 36b of the lower portion 33b. The protrusion 32 is arranged completely within the upper end surface 36a (see in particular FIG. 3). The protrusion 32 includes a side wall surface 32a which arises continuously from the upper end surface 36a in the up direction and a top end surface 32b which is continuous with the side wall surface 32a and which faces upwards. In particular, the top end surface 32b may be parallel to the upper tape surfaces 21a. The upper portion 33a further includes an upper inner side surface 39a which is provided opposite to the edge portion 23 and which extends continuously from the upper end surface 36a downwards towards the upper tape surface 21a and is continuous with an upper leg portion 40a which is arranged at the upper tape surface 21a and is in contact therewith. Similarly, the lower portion 33b includes a lower inner side surface 39b which is provided opposite to the edge portion 23 and which extends continuously from the lower end surface 36a upwards towards the lower tape surface 21b and is continuous with a lower leg portion 40b which is arranged at the lower tape surface 21b and is in contact therewith.

The fastener element 30 further includes an upper back wall surface 41a facing in the back direction and extending in a direction away from the upper tape surface 21a, in the up direction, which is continuous with the upper end surfaces 36a. The fastener element 30 further includes a lower back wall surface 41b facing in the back direction and extending in a direction away from the lower tape surface 21b in the down-direction and which is continuous with the lower end surface 36b. The fastener element 30 further includes an upper front wall surface 42a, facing in the front direction and extending in the direction away from the upper tape surface 21a in the up direction and which is continuous with the upper end surface 36a. The fastener element 30 further includes a lower front wall surface 42b facing in the front direction and extending in the direction away from the lower tape surface 21b in the down direction and which is continuous with the lower end surface 36b.

In the following, the seal part 50 is explained in combination with and without the fastener element 30 in particular with reference to FIGS. 4, 5A, 5C, 6A, 6B and 8. The seal part 50 is preferably made of a material which has some elasticity and which is impermeable to fluid, in particular impermeable to liquid and/or gas. As has been explained already with reference to FIGS. 1 and 2, the seal part 50 of the present embodiment adheres to the tape surface portion 25 of the upper tape surface 21a of the fastener tape 20 and extends over the element surface portion 31 of each fastener element 30. In particular, the element surface portion 31 includes a surface portion of the upper back wall surface 41a and the upper front wall surface 42a of the fastener element 30 as well as a covered portion 36c of the upper end surface 36a. As it is in particular visible in FIG. 6B, the upper end surface 36a includes an uncovered portion 36d which is not covered by the seal part 50 and the covered portion 36c covered by the seal part 50. Furthermore, the fastener element 30 includes a side surface portion 39c which is a portion of the upper inner side surface 39a, and which is for sliding engagement with the boundary of the guide channel of the slider, as will be explained in more detail with reference to FIG. 7, and which is not covered by the seal part 50. That is, the seal part 50 includes a top seal part portion 52 provided on the upper end surface 36a, an outer side seal part portion 53 provided outside of the fastener tape at the connecting portion 34, a back wall seal part portion 55 extending over the upper back wall surface 41a, a front wall seal part portion 56 extending over the upper front wall surface 42a and a bottom seal part portion 54 which adheres to the tape surface portion 25 of the fastener tape 20 and extends over the edge portion 23 of the fastener tape 20 towards the opposite fastener stringer (see for example FIGS. 1 and 8).

As it is shown in FIG. 6B, the top seal part portion 52 has a thickness t in the up-down direction which is smaller than a height h of the protrusion 32 in the up-down direction. Thereby, the protrusion has a protruding portion 32c which protrudes over the top seal part portion 52 in the up-down direction. The protrusion 52 protrudes through the aperture 51 of the seal part 50. In the embodiment shown in the figures, the top seal part portion 52 is in contact with the side wall surface 32a of the protrusion 32 along the circumference of the protrusion 32. However, the invention is not limited to this.

In the following, the interaction of the fastener element 30 with a slider 60 of the slide fastener 100 according to the embodiment of the present invention will be explained with reference to FIG. 7. FIG. 7 is the same sectional view as the one shown in FIG. 6B in which the slider 60 is moved over the fastener element 30. To simplify the representation, only the left fastener stringer 1 of the pair of fastener stringers of the slide fastener 100 and only a part of the slider 60 is shown in FIG. 7. The slider 60 is provided slidably at the fastener element rows 3 for engagement and disengagement of opposing fastener elements 30. The slider 60 includes an upper blade 61, a lower blade 62 and a guide column 63 connecting the upper and lower blades 61, 62 in the up-down direction. The upper and lower blades 61, 62 and the guide column 63 define a boundary of a guide channel 64 for the fastener elements 30. The upper blade 61 includes an upper blade surface 61a which extends parallel to the upper tape surface 21a. The upper blade 61 further includes left and right upper flanges (only the left upper flange 61b is shown in FIG. 7) which protrude from left and right side portions of the upper blade surface 61a in the left-right direction, respectively, towards the lower blade 62 in the down direction. Similarly, the lower blade 62 includes a lower blade surface 62a which extends parallel to the lower tape surface 21b. The lower blade 62 includes left and right lower flanges (only the left lower flange 62b is shown in FIG. 7) which protrude from left and right side portions of the lower blade surface 62a in the left-right direction, respectively, towards the upper blade 61 in the up-down direction.

In the embodiment shown in FIG. 7, the top end surface 32b of the protrusion 32 is in sliding engagement with the upper blade surface 61a of the slider 60 when the slider 60 is moved along the fastener element rows 3 in the front-back direction to engage and disengage the fastener elements 30. A clearance C between the upper blade surface 61a and the top seal part portion 52 provided on the upper end surface 36a of the fastener element 30 is kept due to the protrusion 32 extending through the aperture 51 of the seal part 50 in the up-down direction.

The left upper flange 61b is provided with an inner flange surface 65 which faces the fastener element 30 in the left-right direction and which is provided for sliding engagement with the side surface portion 39c of the fastener element 30 to thereby guide the fastener elements 30 of the opposing fastener stringers towards each other for their engagement. As the seal part 50 extends over the fastener element 30 without extending over the side surface portion 39c, the inner flange surface 65 does not come into contact with the seal part 50. Furthermore, as the upper end surface 36a includes the uncovered portion 36d which is not covered by the seal part 50, the top seal part portion 52 is prevented from contacting the boundary of the guide channel 64 even when the fastener element is slightly tilted within the guide channel 64 with respect to the tape length direction. Thereby, additional protection of the seal part 50 against damage caused by the slider 60 is provided.

As one may take from FIG. 1, and also from the perspective view of the fastener stringer 1 shown in FIG. 8, in a plan view on the upper tape surface 21a of the fastener tape 20, a distance between neighboring fastener elements 30 increases from the tape inner portion 26 towards the edge portion 23 of the fastener tape 20. That is, there is a groove 4 formed between neighboring fastener elements 30 which widens in the front-back direction when it extends from the tape inner portion 26 towards the edge portion 23. This groove 4 helps to suppress a peeling force when the fastener stringer 1 or the fastener tape 20 is bent in the tape length direction with the lower tape surface 21b facing upwards. If the groove 4 did not widen with its extension towards the edge portion 23, the fastener element 30 would receive a peeling force because of neighboring upper portions 33a pressing against each other. With the groove 4, an interference of neighboring upper portions 33a only happens at a portion of the fastener element 30 located at the tape inner portion 26 which helps to suppress the peeling force.

FIGS. 9A and 9B are partial perspective views of upper and lower sides of the slide fastener 100 according to the embodiment of the present invention, respectively. The slide fastener 100 includes a pair of fastener stringers 1 as explained above and the slider 60 slidably provided at the fastener element rows 3 for engaging and disengaging the opposing fastener elements 30 of the pair of fastener stringers 1. In FIGS. 9A and 9B, the slide fastener 100 is partially open. When the slider 60 is moved in the front (F) direction, opposing fastener elements 30 are engaged and the slide fastener 100 is closed. When the slider 60 is moved in the back (B) direction, opposing fastener elements 30 are disengaged and the slide fastener 100 is opened.

In FIG. 9A, the upper tape surface 21a of the fastener tape 20 and the upper blade 61 of the slider 60 and one of the left or right upper flanges 61b thereof is visible. In FIG. 9B, the lower tape surface 21b of the fastener tape 20 and the lower blade 62 of the slider 60 and one of the left or right lower flanges 62b thereof is fully visible, while the upper blade 61 of the slider 60 is partially visible. The upper and lower flanges 61b, 62b are in sliding engagement with the side surface portions 39c of the fastener elements 30 to thereby guide the fastener elements 30 of the opposing fastener stringers 1 toward each other for their engagement. As one may take in particular from FIG. 9A, the two seal parts 50, 50 of the pair of fastener stringers 1 are in sealing abutment when the fastener elements 30, 30 are in the engaged state. The seal part 50 is protected against potential damage caused by the slider 60 as has been explained above with reference to FIG. 7.

The slider 60 may also include a pull tab (not shown) attached to a pull tab attachment rod 66 provided at the upper blade 61 of the slider 60.

The embodiment is not limited regarding the materials from which the fastener elements 30, the fastener tape 20 and the seal part 50 are made. In one example, the fastener tape 20 may include a base sheet onto which a plastic material has been extruded or injected as explained above. In the example, the fastener elements 30 may be made from a first resin material and the seal part 50 may be made from a second resin material. The second resin material and the plastic material may be softer than the first resin material. Hardness/softness may be defined in relation to a Shore A hardness of the materials in one example, but the invention is not limited to this.

As described above, according to the present invention, a slide fastener of the above-referenced type is provided with a structure in which at least one of the fastener elements includes a protrusion that extends through an aperture of the seal part in the up-down direction to thereby keep the seal part distant from the boundary of the guide channel.

As the protrusion keeps the seal part distant from the boundary of the guide channel, damage of the seal part due to a contact with the guide channel may be prevented, at least in the vicinity of the at least one fastener element. Thereby, a robust and durable slide fastener with a sealing function may be provided.

Each fastener tape is an elongated member which is long in a tape length direction. The tape length direction may also be denoted as a front-back direction within this specification. A direction in which the slide fastener moves to engage the fastener elements may be called the front direction, and a direction in which the slide fastener moves to disengage the fastener elements may be called the back direction. When the slider slidably provided at the fastener element rows moves in the front direction to engage the fastener elements of the fastener element rows, the slide fastener is closed. When the slider moves in the back direction to disengage the fastener elements from the engaged state, the slide fastener is opened.

Each fastener element row includes a plurality of fastener elements. The fastener elements are attached to opposing side portions of the two fastener tapes at a pitch which is a regular interval in the tape length direction. The fastener elements may in particular be made from a resin material in one example. In particular, the fastener elements may be injected, preferably directly injected, onto the fastener tape in one example.

The slider includes an upper blade (upper wing) and a lower blade (lower wing) which are distant from each other in the up-down direction which is a direction perpendicular to the surfaces of the fastener tapes. A tape width direction is a direction which is perpendicular to the up-down direction and the tape length direction. The tape width direction may also be denoted as a left-right direction within this specification. The upper blade includes an upper blade surface and the lower blade includes a lower blade surface which faces the upper blade surface in the up-down direction. Furthermore, the upper blade includes left and right flanges protruding from left and right side portions of the upper blade surface, respectively, in the down-direction towards the lower blade. Similarly, the lower blade includes left and right flanges protruding from left and right side portions of the lower blade surface, respectively, in the up-direction towards the upper blade. The slider includes two front openings and one back opening defined by the upper and lower blades and the guide column. The upper blade, the lower blade and the guide column define a boundary of the guide channel for the fastener elements. That is, when the slider moves along the fastener element rows, the fastener elements pass through the guide channel. The fastener elements are in sliding engagement with the boundary of the guide channel when the slider moves along the rows of fastener elements to thereby engage or disengage the fastener elements.

The seal part is made of a material which allows to provide a sealing function. In particular, the seal part may be impermeable to fluid, in particular liquid and/or gas. The seal part may be made of a plastic material or a resin in one example and has preferably flexibility. Apart from its sealing function, the seal part may provide an additional fixation of the fastener elements on the fastener tape as the seal part adheres to the tape surface portion and extends over the fastener elements. To this end, the seal part is preferably made of a material which adheres well to the fastener tape. In general, the tape surface portion is only a section of an upper and/or lower tape surface of the fastener tape, i.e., the seal part does not cover the complete upper and/or lower tape surface. In one example, the tape surface portion may be a section of only the upper tape surface. In another example, the tape surface portion may be a section of only the lower tape surface. Preferably, the tape surface portion includes a portion of the side portion of the fastener tape between neighboring fastener elements. It is preferable that the seal part extends beyond the fastener tape to which it adheres towards the opposite fastener tape to thereby facilitate the sealing abutment of the opposite seal parts. The seal part may include a seal edge portion which may be in sealing abutment with the seal edge portion of the opposite seal part. In one example, the seal edge portion may extend in a straight line along the tape length direction. While the seal part has preferably flexibility, the flexibility should not be too high to ensure the fixation function of the fastener elements. For the at least one fastener element, the element surface portion over which the seal part extends is preferably a section of the fastener element surface without a protruding surface of the protrusion. I.e. there is a surface portion of the at least one fastener element in addition to the protruding surface of the protrusion which is not covered by the seal part.

In one example, the seal part may be injected, preferably directly injected, onto the tape surface portion and the element surface portion.

As the protrusion extends through the aperture of the seal part in the up-down direction, a large fixation strength between the seal part and the at least one fastener element having the protrusion may be ensured as a displacement of the at least one fastener element with respect to the seal part in a direction transverse to the up-down direction may be suppressed. As a result, the seal part may also hold the at least one fastener element more strongly on the fastener tape compared to the related art. In this way, an additional manufacturing step for fixing the at least one fastener element on the fastener tape, e.g. plasma treatment, may not be necessary. As a result, a durable slide fastener may be manufactured more efficiently.

The protrusion may be a single protrusion. Alternatively, the protrusion may include more than one protrusion which protrude in the same or different directions from the at least one fastener element. In particular, a top and/or bottom surface portion of the protrusion which is directed in the up-down direction may be in sliding engagement with the upper or lower blade of the slider when the slider is moved over the fastener element rows. In particular, the top and/or bottom surface portion may be facing the upper or lower blade surfaces of the upper or lower blades in the up-down direction. In one embodiment, the top and/or bottom surface portion of the protrusion may extend parallel to the tape surface.

In one example, the slide fastener may include only one fastener element with the protrusion. However, the invention is not limited to this, and there are examples where more than one, and in particular several of the fastener elements each include a protrusion. For a slide fastener having several fastener elements each with a protrusion, the seal part may be particularly well kept distant from the boundary of the guide channel. In one embodiment of the present invention, each of the fastener elements may include the protrusion that extends through the aperture of the seal part in the up-down direction to thereby keep the seal part distant from the boundary of the guide channel. In this embodiment, the seal part may be protected particularly well against damage due to contact with the guide channel.

In one embodiment of the slide fastener, the fastener tape may include a base sheet which is coated with and/or impregnated by a plastic material which is impermeable to fluid. Thereby, the sealing function of the slide fastener may be further improved. The fluid may be a liquid and/or a gas, and in particular the fluid may be water. The base sheet may be made of a woven or non-woven material in one example. In one example, both upper and lower tape surfaces may be coated with the plastic material. In another example, only one of the upper and lower tape surfaces may be coated with the plastic material. The plastic material may be a resin material in one example. In one example, the plastic material may be provided in the form of a film or a layer on the base sheet of the fastener tape and preferably on at least one of the upper and lower surfaces of the base sheet. In one example, the plastic material may be extruded onto the base sheet. In another example, the plastic material is extruded or injected onto one surface of the base sheet so that the surface may be coated thickly and the other side may be coated less thickly, with gaps of fabric of the base sheet permeated by the plastic material.

The plastic material and the materials from which the fastener elements and the seal part are made are not particularly limited. In one example, the plastic material and the material from which the fastener element and the seal part are made are all different from each other. In one expedient example, the fastener element material has a higher melting point than the plastic material and/or the seal part material. In one example, the tensile strength of the seal part material is preferably at least 20 MPa and at most 80 MPa, more preferably at least 30 MPa and at most 70 MPa and most preferably at least 30 MPa and at most 60 MPa. In one example, the tensile strength of the seal part material is 50 MPa.

In one example, the elongation of the seal part material is preferably at least 500% and at most 800%, more preferably at least 600% and at most 700%. In one example, the elongation of the seal part material is 650%.

In one example, the Shore A hardness of the seal part material according to DIN ISO 7619-1 is preferably at least 70 and at most 100, preferably at least 80 and at most 90. In one example the Shore A hardness of the seal part material is 85.

In one embodiment of the invention, the fastener elements may be made from a first resin, the seal part may be made from a second resin, and the first resin is harder than the plastic material and the second resin. In one example, the hardness may be the Shore A hardness, but the invention is not limited to this. In one example, the second resin and the plastic material may be the same material or similar materials. In particular, the second resin and the plastic material may be such that they mix in one example. It is preferable that the second resin and the plastic material mix well. In particular, the second resin and the plastic material are such that they adhere to each other in one example, and in particular they adhere well to each other. In another example, the second resin may be a different material than the plastic material. In one embodiment, the second resin may be harder than the plastic material. The hardness may be the Shore A hardness in one example, but the invention is not limited to this. Thereby, good sealing properties may be obtained while the fastener tape has flexibility.

In one expedient embodiment of the invention, the first resin includes a polyamide resin, the plastic material includes a first polyurethane and the second resin includes a second polyurethane. In particular, the first resin is the polyamide resin, the plastic material is the first polyurethane and the second resin is the second polyurethane. Fastener elements made from a polyamide resin are durable and have good molding properties which is preferable for the manufacturing. Polyurethane has good sealing properties. However, polyurethane and polyamide do not adhere well to each other. Thus, the first and second polyurethane are preferable such that they adhere to each other, in particular adhere well to each other, to thereby ensure that the fastener elements are additionally fixed on the fastener tape by the seal part. Preferably, the first polyurethane and the second polyurethane are different from each other. In an expedient embodiment, the second polyurethane has a higher softness than the first polyurethane. Hardness/softness may be defined in relation to the Shore A hardness of the polyurethanes in one example, but the invention is not limited to this. It is further preferable, in particular for the manufacturing of the slide fastener, that the polyamide resin has a melting point which is higher than the melting point of the first and/or second polyurethane in one example. In one expedient example, the polyamide is PA612, the first polyurethane is Elastollan 1180A and the second polyurethane is Elastollan C85A.

In another embodiment of the slide fastener according to the present invention, the at least one of the fastener elements may include an upper end surface facing in an up-direction and being distant from an upper tape surface of the fastener tape in the up-direction, an opposite lower end surface facing in a down-direction and being distant from a lower tape surface of the fastener tape in the down-direction, and the protrusion protrudes from at least one of the upper and lower end surfaces.

The upper tape surface of the fastener tape is a surface facing in the up-direction, and the lower tape surface of the fastener tape is a surface facing in the down-direction. In one example, the protrusion protrudes from only one of the upper and lower end surfaces of the at least one fastener element. In another example, there may be more than one protrusion, one of which protrudes from the upper end surface and another one protrudes from the lower end surface in the up-down direction. In another example, there may be more than one protrusion protruding from the upper end surface. In another example, there may be more than one protrusion protruding from the lower end surface. In one example, the protrusion may have a rectangular shape in a plan view onto the fastener tape surface. The protrusion may be arranged completely within the respective upper or lower end surface and the seal part may extend over the respective end surface so as to surround the protrusion completely thereby forming an aperture at the location of the protrusion. In this way, the at least one fastener element may be particularly well fixed on the fastener tape. A thickness of the seal part provided on the upper or lower end surfaces is smaller than the protruding height of the protrusion from the upper or lower end surfaces so that the protrusion protrudes over the seal part in the up-down direction. In one embodiment, the seal part may be in contact with the protrusion along its circumference. The portion of the seal part which is provided on the upper or lower end surfaces may have a uniform thickness. In one example, a ratio of a thickness t of the seal part on the upper or lower end surfaces and a protruding height h of the protrusion from the upper or lower end surfaces t/h, may be between 0.6 and 0.9, and preferably between 0.7 and 0.8 in one example.

In a further embodiment of the slide fastener according to the present invention, the at least one of the fastener elements may include a side surface portion provided opposite to an edge portion of the fastener tape and configured to be in sliding engagement with the boundary of the guide channel to thereby guide the fastener elements towards each other for the engagement, and the seal part extends over the fastener elements without extending over the side surface portion. In one embodiment, each of the fastener elements having the protrusion also has the side surface portion, and the seal part extends over the fastener elements without extending over the side surface portion. In one example, each fastener element has the side surface portion and the seal part extends over each fastener element without extending over the side surface portion. The edge portion of the fastener tape is facing the opposite fastener tape and is an outer boundary of the side portion to which the fastener elements are attached. The side surface portion of the fastener element is in particular in sliding engagement with the left or right flanges of the slider. The side surface portion may also be in sliding engagement with the left and/or right side portions of the upper and/or lower blade surfaces of the upper and/or lower blades. As the seal part extends over the fastener element without extending over the side surface portion of the fastener element, the seal part may cover a large surface of the fastener element without there being a risk of a contact between the seal part and the boundary of the guide channel when the slider is moved along the fastener element rows. Thereby, the fastener elements may be fixed well to the fastener tape while damage of the seal part may be further prevented.

The form of the fastener elements of the slide fastener of the present invention is not particularly limited. In an expedient embodiment, each of the fastener elements may include an upper portion provided on an upper tape surface of the fastener tape, a lower portion provided on a lower tape surface of the fastener tape, and a connecting portion connecting the upper and lower portions in the up-down direction and being provided outside the fastener tape at an edge portion thereof. The fastener element is thus clamped to the side portion of the fastener tape. The related fastener elements are disclosed in the related art. When these fastener elements are used for conventional slide fasteners, they may not be fixed sufficiently well on the fastener tape by clamping only as the fastener elements and the fastener tape may be made from different materials which may not adhere well to each other. Therefore, an additional manufacturing step, like plasma treatment, may be required to obtain a sufficient fixation of the fastener elements on the fastener tape. In the present invention, the fastener elements are also fixed to the fastener tape by the seal part which is adhered to the tape surface portion of the fastener tape and extends over the element surface portion of the fastener element. Thereby, the additional step of plasma treatment which may be required for slide fasteners of the related art without the seal part extending over the fastener elements may be avoided, and thereby manufacturing efficiency may by increased. In one example, the seal part may cover the connecting portion at least partially. In one example, the seal part may cover the connecting portion completely.

Furthermore, the slide fastener with the fastener elements according to the above embodiment does not require that holes are provided in the fastener tape through which the connection portion passes in the up-down direction, which is also beneficial from the point of manufacturing efficiency and fluid tightness.

In one expedient embodiment of the present invention, an edge portion of the fastener tape may include a core thread. The core thread has in particular an extension in the up-down direction which is larger than the thickness of an inside of the fastener tape. The core thread may improve the fixation of the fastener elements on the fastener tape, in particular, when the fastener elements are according to the above embodiment with a connecting portion outside the fastener tape.

In one expedient embodiment, the upper portion may include an upper base portion provided on the upper tape surface of the fastener tape, the lower portion may include a lower base portion provided on the lower tape surface of the fastener tape, and at least one of the upper and lower portions may include a coupling portion extending from at least one of the upper and lower base portions towards the opposite fastener tape and configured to engage with an opposite coupling portion of an opposite fastener element provided on the opposite fastener tape. In one example, only the upper (lower) portion includes the coupling portion, only the lower (upper) portion includes the protrusion and the seal part extends only over the lower (upper) portion. Thereby, a surface of the fastener element on the side of the coupling portion and facing the boundary of the guide channel may be in sliding engagement therewith, and the seal part is kept distant from the boundary of the guide channel due to the protrusion. In this way, a very good sealing function of the slide fastener may be ensured while the seal part is protected against damage due to the movement of the slider.

In a further embodiment of the slide fastener, in a plan view on at least one of upper and lower tape surfaces, a distance between the neighboring fastener elements may increase from a tape inside towards an edge portion of the fastener tape. Thereby, a widening groove having a width which increases from the tape inside towards the edge portion of the fastener tape is provided between the fastener elements. In this way, an undesirable peeling force which may be applied to a conventional fastener element without the widening groove in a bending test where the fastener stringer is bent in the tape length direction may be suppressed. Namely, at the bending test where the fastener tape of the conventional slide fastener is bent in the length direction with the lower portion facing up, a fastener element would receive a peeling force, in particular at the edge portion, in particular at the coupling portion because of neighbouring upper portions pressing each other without the groove. While the fastener element may be able to withstand a peeling force at the tape inside where it may be fixed strongly onto the fastener tape, it may not be able to withstand a peeling force at the edge portion, in particular at the coupling portion. For the slide fastener according to the present invention, at such bending, an interference happens only at the tape inside portion of the fastener element, which makes a force reverse to the peeling force which consequently off-sets the peeling force.

In one example of the above embodiment, in the plan view of the fastener tape, a portion of at least one of the upper and lower base portions may have a trapezoidal shape with bases extending in the tape length direction. In the example where only the upper (lower) portion includes the coupling portion, it may be preferable that at least the portion of the lower (upper) base portion has the trapezoidal shape in the plan view. For this example, the peeling force may be suppressed particularly well.

In a further embodiment of the slide fastener according to the present invention, the coupling portion may be arranged in the up-down direction so as to include a center line of the fastener tape in the up-down direction. The center line extends in the tape width direction and is located in the center of the fastener tape in the up-down direction. In conventional fastener stringers, the coupling portion of the fastener element is generally arranged offset from the center line. Thereby, when the fastener elements are in the engaged state, a force applied to the fastener elements on the opposite fastener tapes in the tape width direction away from each other may create a rotational moment on the fastener elements. However, when the coupling portion is arranged so as to include the center line of the fastener tape, a force applied to the fastener elements on the opposite fastener tapes in the tape width direction away from each other is less likely to generate a rotational moment. Thereby, it is less likely that the fastener elements are disengaged or that the seal parts lose their sealing abutment. Thereby, the sealing function of the slide fastener may be further improved.