FABRIC TOUCH FASTENER HAVING HOOK-SHAPED ENGAGEMENT ELEMENTS

Description

Technical Field

[0001] The present invention relates to a hook-and-loop fastener made of a woven fabric having hook engagement elements (fabric touch fastener having hook-shaped engagement elements), particularly to a hook type hook-and-loop fastener made of a woven fabric, in which a hook engagement element formed of a monofilament having excellent flexibility hardly causes fibrillation of the monofilament even when engagement and peeling are frequently repeated, or to a hook-and-loop coexistence type fastener having both such hook engagement elements and loop engagement elements on the same surface of a base fabric.

Background Art

[0002] Conventionally, as a hook-and-loop fastener having a woven base fabric, a combination of a so-called hook type hook-and-loop fastener having a plurality of hook engagement elements formed of a monofilament on the surface of the base fabric and a so-called loop type hook-and-loop fastener having a plurality of loop engagement elements formed of a multifilament yarn engageable with the hook engagement elements on the surface of the base fabric has been widely used.

[0003] For the hook type hook-and-loop fastener used in such a combination, a polyamide-based monofilament represented by nylon 6 has been widely used as a hook engagement element. However, when a polyamide-based monofilament is used, there is a disadvantage that the hook type hook-and-loop fastener is waved by water absorption, moisture absorption, and heat. In addition, when a polyamide-based monofilament is used, it is necessary to attach the hook-and-loop fastener to the clothing after dyeing due to differences in dyeability since polyester-based fibers are the main fibers used to make up clothing in recent years, and therefore many different color tones of hook-and-loop fasteners must be kept in stock to match the color tone of the clothing.

[0004] As a hook type hook-and-loop fastener that solves the drawbacks and problems of such a hook type hook-and-loop fastener formed of a polyamide-based monofilament, a hook-and-loop fastener having a hook engagement element using a monofilament formed of a polyethylene terephthalate-based polyester has been proposed (PTL 1).

[0005] When such a monofilament formed of a polyethylene terephthalate-based polyester is used for the hook engagement element, the above-mentioned drawbacks and problems can be solved, and in addition, since the monofilament is rigid, it is difficult for the monofilament to come off from the loop engagement element, and as a result, a high engagement force can be obtained.

[0006] However, when a monofilament formed of a polyethylene terephthalate-based polyester is used as the hook engagement element, since the hook engagement element is too rigid, the loop engagement element to be engaged with the hook engagement element is likely to be cut, and further, when an instantaneous load, i.e., impact by repeated peeling occurs due to excessive rigidity, the hook is elongated, deformed, and hard to restore. In addition, since the hook engagement element is too rigid, it has a poor touch on the skin, and it has a problem that it is not necessarily suitable for a supporter or clothing application requiring flexibility.

[0007] As a hook engagement element for solving the above-mentioned problems of the polyethylene terephthalate-based polyester, a hook type hook-and-loop fastener using a monofilament formed of a polybutylene terephthalate-based polyester has been proposed (PTL 2). That is, since the monofilament formed of a polybutylene terephthalate-based polyester is much more flexible than a polyethylene terephthalate-based polyester, it does not cut the loop engagement element of the engagement partner, easily keeps the hook shape for a long time, easily rises even when the engagement element falls down, and a large number of loop fibers easily enter the hook, so that high engagement force and excellent engaging durability can be obtained. Furthermore, since the monofilament formed of a polybutylene terephthalate-based polyester is flexible, it has a soft touch on the skin and is suitable for applications in the field of direct contact with the skin, such as supports and clothing applications.

[0008] Moreover, since the polybutylene terephthalate-based polyester can be dyed in the same color at the same time under the same dyeing conditions as the polyethylene terephthalate-based polyester, it can be dyed in the same color only by attaching a colorless hook-and-loop fastener to clothing or the like made of a polyethylene terephthalate-based fiber before dyeing, thereby eliminating the problem that the hook-and-loop fastener having many color tones due to differences in dyeability such as the polyamide-based hook-and-loop fastener must be kept in stock.

[0009] Although a hook-and-loop fastener having hook engagement elements composed of monofilaments formed of a polybutylene terephthalate-based polyester has excellent performance, it has been found that when a hook type hook-and-loop fastener using a monofilament formed of a polybutylene terephthalate-based polyester as a hook engagement element is used for applications in which the number of repetitions of engagement and peeling is extremely high, such as a sphygmomanometer, a supporter, an artificial limb, a shoe, a bag, or a toy, the polybutylene terephthalate-based monofilament in the hook engagement element portion gradually fibrillates when the peeling is frequently repeated.

[0010] When the monofilament is fibrillated, a tear is generated parallel to the length direction of one monofilament, the rigidity necessary as a hook engagement element is lost, and it becomes difficult to engage with the loop engagement element, and when it becomes high, the monofilament is finely divided, and it becomes difficult for the hook engagement element to maintain the hook shape, and the engagement strength decreases. When fibrillation is further promoted, the fibrillated hook engagement element itself is cut and disappears.

[0011] For example, in a sphygmomanometer installed in a hospital or nursing home, a hook-and-loop fastener is used as a cuff, and a hook-and-loop fastener having hook engagement elements composed of a monofilament formed of a polybutylene terephthalate-based polyester is preferable in terms of skin touch and flexibility. In the case of such a sphygmomanometer having a high frequency of use, a hook engagement element composed of a monofilament formed of a polybutylene terephthalate-based polyester causes fibrillation when engagement and peeling are repeated, resulting in a decrease in engagement strength, and as the fibrillation proceeds, the fibrils are gradually cut off, and finally, the hook engagement element itself disappears and the function as a sphygmomanometer disappears.

[0012] The monofilament used for the hook engagement element is usually subjected to a drawing treatment at a high ratio in order to increase the tensile strength in the production process, whereby the crystals forming the monofilament are aligned in the longitudinal direction of the monofilament, and this causes the monofilament to be easily torn in the longitudinal direction, which is considered to cause fibrillation.

Citation List

Patent Literature

[0013] 

PTL 1: JP 2013-244139 A

PTL 2: JP 2014-27988 A

[0014] Document JP201802991A also discloses a hook and loop fastener of the prior art.

Summary of Invention

Technical Problem

[0015] An object of the present invention is to solve a new problem of a hook-and-loop fastener made of a woven fabric, having a hook engagement element composed of a monofilament formed of a polybutylene terephthalate-based polyester having such excellent performance, i.e., a problem that when the monofilament forming the hook engagement element is repeatedly engaged and peeled frequently, the monofilament is fibrillated to cause a tear in the longitudinal direction of the monofilament, and further as the fibrillation proceeds, one monofilament is thinly torn to make it difficult to maintain the hook shape of the hook engagement element, resulting in loss of engagement strength. Solution to Problem

[0016]  That is, the present invention relates to a hook-and-loop fastener comprising a base fabric having existing on a surface thereof a plurality of hook engagement elements, wherein monofilaments constituting the hook engagement elements are formed of a polybutylene terephthalate-based polyester containing 0.2 to 8% by mass of a polyester elastomer.

[0017] Preferably, in such a hook-and-loop fastener, the base fabric is a woven fabric composed of a warp yarn, a weft yarn, and a monofilament for the hook engagement elements; the warp yarn and the weft yarn are polyethylene terephthalate-based multifilament yarns; the weft yarn has heat fusibility; the monofilament for hook engagement elements is inwoven into the woven fabric in parallel to the warp yarn; the hook engagement element is formed at a position where the monofilament for hook engagement elements crosses over a plurality of warp yarns; and the root of the hook engagement element is fixed to the base fabric through fusion of the weft yarn.

[0018] More preferably, in such a hook-and-loop fastener, the base fabric has a plain weave structure, the monofilament for hook engagement elements is inwoven into the woven base fabric every four warp yarns in parallel to the warp yarn, and the hook engagement element is formed by allowing five weft yarns to float and sink, then crossing over three warp yarns and one weft yarn to form a loop at the crossing position, and cutting one leg of the formed loop. Still more preferably, in such a hook-and-loop fastener, the monofilament for hook engagement elements is a monofilament having a diameter of 0.1 to 0.23 mm.

[0019] In addition, according to the present invention, in such a hook-and-loop fastener, a part of the monofilament for hook engagement elements is replaced with a multifilament yarn made of polybutylene terephthalate for loop engagement elements, the multifilament yarn is inwoven into a woven fabric in parallel to the warp yarn, a loop is formed at a position crossing over one weft yarn without crossing over the warp yarn, and a loop engagement element is formed without cutting one leg of the loop , and the loop engagement element and the hook engagement element coexist on the surface of the base fabric.

[0020] Advantageous Effects of Invention

[0021] In the present invention, a polybutylene terephthalate-based polyester containing 0.2 to 8% by mass of a polyester elastomer is used as a monofilament constituting the hook engagement element. As described above, by blending the polyester elastomer in the monofilament, it is possible to prevent the monofilament of the hook portion from fibrillating even if frequent engagement and peeling of the hook engagement element is repeated frequently, and as a result, it is possible to prevent the engagement strength from decreasing.

[0022] The monofilament formed of a polybutylene terephthalate-based polyester blended with a polyester elastomer, which constitutes the hook engagement element of the present invention, is obtained by so-called blend spinning in which chips of a polyester elastomer are blended when polybutylene terephthalate-based polyester chips are melt-spun. In general, it is known that when blend spinning is carried out, in the obtained fiber, peeling is likely to occur at the interface between two kinds of polymers, and fibrous physical properties are reduced and fibrillation is likely to occur. However, in the present invention, contrary to this general tendency, fibrillation is conversely suppressed.

[0023] The fact that the polyester elastomer has an effect of suppressing fibrillation of the monofilament formed of the polybutylene terephthalate-based polyester without increasing fibrillation of the monofilament is surprising, although the polybutylene terephthalate-based polyester and the polyester elastomer are largely different in physical properties such as stretching behavior.

[0024] Moreover, the monofilament formed of the polybutylene terephthalate-based polyester blended with the polyester elastomer does not differ from the monofilament formed of the polybutylene terephthalate-based polyester alone which is not blended in terms of dyeability, and the existence of the polyester elastomer does not impair the excellent dyeability of the monofilament formed of the polybutylene terephthalate-based polyester.

Brief Description of Drawings

[0025] 

Fig. 1 is a photograph showing a state of a hook engagement element of a hook-and-loop fastener according to the present invention in the case where engagement and peeling of the hook engagement element are frequently repeated.

Fig. 2 is a photograph showing a state of a hook engagement element of a conventional hook-and-loop fastener in the case where engagement and peeling of the hook engagement element are frequently repeated.

Description of Embodiments

[0026] Hereinafter, the present invention will be described in detail.

[0027] First, the hook-and-loop fastener according to the present invention is a hook-and-loop fastener in which a plurality, preferably a large number (about 30 elements/cm² to 120 elements/cm²), of hook engagement elements formed of a monofilament, i.e., engagement elements in which the monofilament is looped and then heated to fix the loop shape, and then one leg of the loop is cut to make the loop into a hook, exist on the surface of the base fabric.

[0028] The base fabric is preferably a woven fabric woven from a warp yarn, a weft yarn, and a monofilament for hook engagement elements. It is particularly preferable that the warp yarn and the weft yarn are multifilament yarns and the weft yarn has heat fusibility, the monofilament for hook engagement elements is inwoven into the woven fabric in parallel to the warp yarn, the hook engagement element is formed at a position where the monofilament for hook engagement elements crosses over a plurality of warp yarns, and the root of the hook engagement element is fixed to the base fabric through fusion of the weft yarn.

[0029] In the present invention, the term "heat fusibility" refers to a property of being softened by heating, and more specifically, means that when a heat fusible fiber is heated to a certain temperature or higher, it is softened and can be fused to a fiber formed of the same material or a different material, which is in close contact with the fiber.

[0030] The warp yarn is preferably a multifilament yarn substantially composed of a polyethylene terephthalate-based polyester polymer from the viewpoint of not causing waviness (a state in which the surface of the base fabric of the hook-and-loop fastener irregularly rises and falls and does not become a horizontal surface) due to heat, water absorption, and moisture absorption, and further from the viewpoint of improving the heat fusibility of the weft yarn. More preferably, the warp yarn is a multifilament yarn formed from a polyethylene terephthalate homopolymer.

[0031] As for the thickness of the multifilament yarn used as the warp yarn, a multifilament yarn composed of 20 to 54 filaments and having a total dtex of 100 to 300 dtex is preferable, and a multifilament yarn composed of 24 to 48 filaments and having a total dtex of 150 to 250 dtex is particularly preferable.

[0032] In the hook-and-loop fastener of the present invention, the weft yarn preferably contains a heat fusible multifilament yarn. As a preferable representative example of the heat fusible multifilament yarn, there can be mentioned a multifilament yarn in which core-sheath type heat fusible filaments having a sheath component as a heat fusible component are bundled.

[0033] Since the weft yarn contains the heat fusible multifilament yarn, the monofilament for engagement elements can be firmly fixed to the base fabric, and there is no need to apply a polyurethane-based or acrylic-based back coating resin to the back surface of the base fabric of the hook-and-loop fastener in order to prevent the monofilament for engagement elements from being pulled out from the base fabric as in the conventional hook-and-loop fastener. Therefore, the process can be simplified, and since the back surface of the base fabric is not hardened by the back coating resin, the flexibility and air permeability of the hook-and-loop fastener are not hindered. Further, there is no problem of deterioration of dyeability of the hook-and-loop fastener due to the existence of the back coating resin layer.

[0034] As for the above-mentioned core-sheath type heat fusible multifilament yarn, a suitable example is a multifilament yarn formed by bundling a plurality of core-sheath type filaments, where the sheath component is formed of a polyester-based resin that melts under heat treatment conditions and can firmly fix the root of the monofilament for hook engagement elements to a base fabric, and the core component is formed of a polyester-based resin that does not melt under heat treatment conditions.

[0035]  Specifically, a representative example is a core-sheath type polyester-based multifilament yarn having polyethylene terephthalate as the core component and copolymerized polyethylene terephthalate having a melting point or a softening point largely lowered by copolymerizing, for example, 20 to 30 mol% of a copolymerization component represented by isophthalic acid, adipic acid or the like in a large amount as the sheath component. The melting point or softening point of the sheath component is preferably 100 to 200°C, and is preferably 20 to 150°C lower than the melting point of the warp yarn, the core component, or the monofilament for hook engagement elements. The cross-sectional shape of the core-sheath type heat fusible fiber may be a concentric core-sheath type, an eccentric core-sheath type, a single-core core-sheath type, or a multi-core core-sheath type.

[0036] Furthermore, it is preferable that all of the multifilament yarns constituting the weft yarns are the heat fusible multifilament yarns because the monofilaments for hook engagement elements are firmly fixed to the base fabric. In the case where the multifilament yarn constituting the weft yarn does not have a core-sheath cross-sectional shape, but the entire cross-section is formed of a heat fusible polymer, the heat fusible polymer that has melted and solidified again is brittle and easily broken, and in the case of sewing or the like, the base fabric is easily torn from the sewing thread portion. Therefore, the heat fusible multifilament yarn preferably contains a non-heat fusible resin, and preferably has a core-sheath cross-sectional shape. The mass ratio of the core component to the sheath component is preferably in the range of 50:50 to 80:20, particularly preferably in the range of 55:45 to 75:25.

[0037] The weft yarn is preferably a multifilament yarn, and the thickness of the multifilament yarn constituting the weft yarn is preferably a multifilament yarn composed of 10 to 72 filaments and having a total dtex of 80 to 300 dtex, and particularly preferably a multifilament yarn composed of 18 to 36 filaments and having a total dtex of 90 to 200 dtex.

[0038] What is important in the present invention is that the resin forming the monofilament for hook engagement elements is a polybutylene terephthalate-based polyester blended with 0.2 to 8% by mass of a polyester elastomer.

[0039] A monofilament formed of polybutylene terephthalate blended with a polyester elastomer can be easily obtained by so-called blend spinning in which polybutylene terephthalate chips are blended with polyester elastomer chips and spun as described above.

[0040] When 0.2 to 8% by mass of the polyester elastomer is blended, fibrillation is much less likely to occur as compared with the case of a monofilament formed of polybutylene terephthalate alone (that is, polybutylene terephthalate to which the polyester elastomer is not blended) even if peeling is repeated frequently. In the present invention, "0.2 to 8% by mass of the polyester elastomer is blended" refers to a value relative to the mass of the polybutylene terephthalate-based polyester. Of course, if the amount of the resin or the like other than the polybutylene terephthalate and polyester elastomer is small, the resin may be blended as other component within a range not impairing the performance, and furthermore, as other components, various stabilizers, colorants, and the like may be added within a range not impairing the performance. The total mass of the two components of polybutylene terephthalate and a polyester elastomer is preferably 80% by mass or more, more preferably 90% by mass or more, and particularly preferably 100% by mass (only two components of polybutylene terephthalate and polyester elastomer) with respect to the mass of the polybutylene terephthalate-based polyester ("polybutylene terephthalate" + "polyester elastomer" + "other optional component").

[0041] When the resin to be blended is not a polyester elastomer but another elastomer, for example, a polyurethane-based elastomer, a polyolefin-based elastomer, or a polystyrene-based elastomer, the fibrillation resistance is not improved, but rather fibrillation is promoted by repeating engagement and peeling frequently. Therefore, this is an effect peculiar to the polyester elastomer.

[0042] In the present invention, the polyester elastomer blended into the monofilament constituting the hook engagement element is preferably a resin obtained by copolymerizing polyoxytetramethylene glycol with a resin having a butylene terephthalate unit as a main repeating unit, and is preferably a resin having sufficient properties of an elastic polymer in spite of a high elastic modulus. In the present invention, the proportion of the [poly(oxytetramethylene)] terephthalate group in the polyester elastomer is preferably in the range of 40 to 70% by mass, and more preferably in the range of 50 to 60% by mass.

[0043] When the blending amount of the polyester elastomer is less than 0.2% by mass with respect to the polybutylene terephthalate-based polyester, the effect of blending the polyester elastomer is hardly exhibited. On the other hand, when the blending amount exceeds 8% by mass, the monofilament becomes too soft, and the hook shape opens with a low force, so that a high engagement strength cannot be obtained. The polyester elastomer is preferably blended in an amount of 0.5 to 5% by mass, more preferably 0.5 to 3% by mass, still more preferably 1 to 3% by mass.

[0044] Fig. 1 is a photomicrograph of a hook engagement element formed from a monofilament formed of polybutylene terephthalate blended with 2% by mass of a polyester elastomer, and Fig. 2 is a photomicrograph of a hook engagement element formed from a monofilament formed of polybutylene terephthalate alone blended with no polyester elastomer, each at a time point of repeating 20000 times of engagement and peeling.

[0045] In the hook engagement element shown in Fig. 1, neither fibrillated nor torn in the longitudinal direction of the monofilament, which is a sign of fibrillation, is observed at all, whereas in the hook engagement element shown in Fig. 2, the root is whitened by fibrillation and the monofilament is torn in the longitudinal direction, and further, thin fibrillated fibers separated and independent from the monofilament by fibrillation exist.

[0046] The polybutylene terephthalate-based polyester constituting the monofilament is a resin obtained from terephthalic acid and butanediol, and other copolymerization components may be copolymerized in a small amount within a range that does not impair the performance of the polybutylene terephthalate. The proportion of the other copolymerization component is preferably 20% by mass or less, more preferably 10% by mass or less, still more preferably 5% by mass or less, and particularly preferably 0% by mass with respect to the total components.

[0047] The thickness of the monofilament for hook engagement elements is preferably 0.10 to 0.23 mm in diameter from the viewpoint of achieving both engagement strength and soft touch feeling, and more preferably 0.14 to 0.20 mm in diameter.

[0048] A woven fabric for a hook-and-loop fastener is woven from the warp yarn, the weft yarn, and the monofilament for hook engagement elements described above. As for the weaving structure of the woven fabric, a plain weave in which the monofilament for hook engagement elements is a part of the warp yarn is preferable, and specifically, a weaving structure in which the monofilament for hook engagement elements rises up from the surface of the base fabric in the middle of the structure while existing parallel to the warp yarn and forms a loop for hook engagement elements at a position crossing over a plurality of the warp yarns is preferable.

[0049] The weaving density of the warp yarns is preferably 50 to 90 yarns/cm in terms of a weaving density after heat treatment, and the weaving density of the weft yarns is preferably 15 to 25 yarns/cm in terms of a weaving density after heat treatment. The mass proportion of the weft yarn is preferably 10 to 45% with respect to the total mass of the yarn for loop engagement elements, the warp yarn, and the weft yarn constituting the hook-and-loop fastener.

[0050] The driving number of the monofilament for hook engagement elements is preferably about 3 to 6 per 20 warp yarns (including the monofilament for hook engagement elements). It is particularly preferable that one monofilament for hook engagement elements is driven per five warp yarns (including the monofilament for hook engagement elements), and preferably the monofilament for hook engagement elements is uniformly driven into the warp yarns without being biased. Therefore, it is preferable that the monofilaments for hook engagement elements exist on both sides of four continuous warp yarns on average.

[0051] In particular, in the present invention, it is preferable that the monofilament for hook engagement elements is inwoven into the woven base fabric every four warp yarns in parallel to the warp yarn, and floats on the weft yarn by floating and sinking five weft yarns, and a loop for hook engagement elements is formed at a position where the monofilament crosses over three warp yarns and one weft yarn, because both the engagement strength and the peeling durability can be satisfied. Then, the loop-formed monofilament is preferably woven in such a manner that the monofilament floats on the weft yarn by floating and sinking five weft yarns again, and returns to the original space between the warp yarns while forming a loop by crossing over three warp yarns and one weft yarn.

[0052] The woven fabric for a hook-and-loop fastener thus obtained is then subjected to heat treatment to melt the sheath component of the core-sheath type heat fusible multifilament yarn constituting the weft yarn. This eliminates the need for back coating treatment which has been performed in the conventional hook-and-loop fastener, and can prevent problems such as deterioration of the workplace environment due to evaporation of the organic solvent used in the back coating resin liquid, adhesion of the back coating resin liquid to the manufacturing apparatus, deterioration of flexibility and air permeability of the hook-and-loop fastener due to the back coating resin, and inhibition of dyeability of the hook-and-loop fastener due to the existence of the back coating resin.

[0053] As the temperature during the heat treatment, a temperature of 150 to 220°C, which is a temperature at which the sheath component of the heat fusible multifilament yarn melts or softens but other monofilaments, yarns, and core components do not melt, is generally used, and more preferably in the range of 185 to 210°C. Further, the shape of the loop for hook engagement elements is fixed by the heat during the heat treatment, and the hook shape is maintained even when one leg of the loop is cut.

[0054] Thus, the hook engagement element is completed by cutting one leg of the loop for hook on the woven fabric for a hook type hook-and-loop fastener having a plurality, preferably a large number (about 30 elements/cm² to 120 elements/cm²) of loops for hook engagement elements in which the shape is fixed in this manner on the surface. Cutting of one leg is usually carried out by a clipper or the like. It is preferable to cut one leg at a position slightly shifted from the center of the loop toward one leg side, that is, when the height of the loop from the surface of the base fabric to the top portion is 1, the loop is cut at a position near the top portion where the height is 2/3 or more of the height from the surface of the base fabric and slightly shifted from the top portion. This is preferable in preventing a higher degree of fibrillation due to frequent engagement and peeling of the monofilament for hook engagement elements.

[0055] The density of the hook engagement elements in the hook type hook-and-loop fastener thus obtained is preferably 25 to 125 elements per cm² on the basis of the base fabric portion where the engagement elements exist. The height of the hook engagement element is preferably 1.0 to 2.5 mm from the surface of the base fabric.

[0056] Although the case of the hook type hook-and-loop fastener has been described in detail above, the present invention is also effective in the case of a so-called hook-and-loop coexistence type fastener in which hook engagement elements and loop engagement elements coexist on the surface of the hook-and-loop fastener, in addition to the hook type hook-and-loop fastener in which only hook engagement elements exist on the surface of the base fabric.

[0057] As the loop engagement element in this case, a multifilament yarn which is easily engaged with the hook engagement element, that is, a multifilament yarn in which a multifilament yarn constituting a so-called loop portion is easily divided into individual filaments (easily loosened) is preferably used. In particular, as the multifilament yarn, it is preferable to use a multifilament yarn which is formed from a polybutylene terephthalate-based polyester which is particularly easily divided (easily loosened) and excellent in flexibility, and which does not melt at a temperature when the heat fusible multifilament yarn is heat-fused.

[0058] The thickness of the multifilament yarn for loop engagement elements is preferably a multifilament yarn in which 5 to 12 filaments of 32 to 45 dtex are bundled.

[0059] It is preferable that the multifilament yarn for loop engagement elements is inwoven in parallel to the warp yarn and forms a loop on the woven fabric every time five weft yarns are floated and sunk. The driving number of the multifilament yarns for loop engagement elements is preferably 3 to 6 per 20 warp yarns in total of the monofilaments for hook engagement elements and the multifilament yarns for loop engagement elements (including the monofilaments for hook engagement elements and the multifilament yarns for loop engagement elements), and the driving number ratio of the monofilaments for hook engagement elements to the multifilament yarns for loop engagement elements is preferably in the range of 30:70 to 70:30. It is particularly preferable that a row in which a plurality of hook engagement elements are arranged in the warp direction and a row in which a plurality of loop engagement elements are arranged in the warp direction coexist alternately on the surface of the woven fabric in units of two rows each.

[0060] In the case of a hook-and-loop coexistence type fastener, only one leg side portion of the loop for hook engagement elements protruding from the surface of the woven fabric for the heat-treated hook-and-loop fastener is cut to obtain a hook engagement element. The cutting position is the same as in the case of the hook type hook-and-loop fastener described above.

[0061] The height of the hook engagement element is preferably 1.5 to 2.5 mm from the surface of the base fabric and lower than the height of the loop engagement element by 0.3 to 0.8 mm. In particular, in the present invention, since the polyester elastomer is blended with the polybutylene terephthalate-based polyester constituting the hook engagement element, flexibility and texture are excellent, and this effect is even more pronounced when the loop engagement element is higher than the hook engagement element.

[0062] The densities of the hook engagement elements and the loop engagement elements in the hook-and-loop coexistence type fastener are preferably 20 to 40 elements per cm² and 20 to 40 elements per cm², respectively, on the basis of the base fabric portion where the engagement elements exist. The ratio of the number of the hook engagement elements to the number of the loop engagement elements is preferably in the range of 40:60 to 60:40.

[0063] In the case of the hook-and-loop coexistence type fastener, it is preferable to rub the surface of the loop engagement element with a card clothing or the like to divide (loosen) the multifilament yarn constituting the loop engagement element into individual filaments in order to enhance the engagement strength. In the case where the height of the loop engagement element is higher than the height of the hook engagement element, the top portion of the hook engagement element is hardly damaged even if rubbed with a card clothing or the like, and the engagement strength is hardly impaired.

[0064] The hook type hook-and-loop fastener and the hook-and-loop coexistence type fastener of the present invention can be used in application fields in which conventional general hook-and-loop fasteners are used, and are particularly suitable for applications in which engagement and peeling are repeatedly performed frequently, and can be used in a wide range of fields such as, for example, sphygmomanometers (particularly sphygmomanometers used in hospitals, nursing facilities, etc.), shoes, bags, hats, gloves, and the like, as well as clothes, supporters, artificial limb fixing materials, binding bands for packing, binding tapes, various toys, fixing of sheets for civil engineering and construction, storage boxes and packing cases that can be freely assembled and disassembled, small articles, and the like. In particular, it is suitable for applications in which it is in direct contact with the skin of the human body, and in which engagement and peeling are frequently performed, such as, for example, the above-described sphygmomanometers, supporters, and artificial limb fixation.

Examples

[0065] Hereinafter, the present invention will be described with reference to Examples. In the Examples, the initial engagement strength was measured in conformity with the method of JIS L3416:2000, and the peeling durability was also measured in conformity with JIS L3416:2000. When the hook-and-loop fastener was a hook type hook-and-loop fastener, a woven fabric-based loop type hook-and-loop fastener B10000 manufactured by Kuraray Fastening Co., Ltd. having an element density of loop engagement elements of 60 elements/cm² was used as the engagement partner, and when the hook-and-loop fastener was a hook-and-loop coexistence type fastener (hook and loop coexistence type fastener F9820Y.12 manufactured by Kuraray Fastening Co., Ltd.), the same hook-and-loop coexistence type fastener was used as the engagement partner.

(Example 1)

[0066] As a warp yarn, a weft yarn and a monofilament for hook engagement elements that constitute a base fabric of a hook-and-loop fastener, the following yarns were prepared.

[Warp Yarn]

[0067] 

Multifilament yarn formed of polyethylene terephthalate having a melting point of 260°C

Total dtex and the number of filaments: 167 dtex and 30 filaments

[Weft Yarn (Multifilament Yarn composed of Core-Sheath Type Composite Filaments)]

[0068] 

Core component: polyethylene terephthalate (melting point: 260°C)

Sheath component: polyethylene terephthalate copolymerized with 25 mol% of isophthalic acid (softening point: 190°C)

Core/sheath ratio (mass ratio): 70:30 (core component : sheath component)

Total dtex and the number of filaments: 110 dtex and 24 filaments

[Monofilament for Hook Engagement Element]

[0069] A polybutylene terephthalate-based polyester monofilament (melting point: 223°C) blended with 2% by mass of a polyester elastomer (polyester elastomer: Hytrel 7247, manufactured by Du Pont-Toray Co., Ltd.), wherein the elastomer is chip-blended during spinning.
Fineness: 200 dtex (diameter: 0.14 mm)

[Manufacturing of Hook Type Hook-and-Loop Fastener]

[0070] Using the warp yarn, the weft yarn, and the monofilament for hook engagement elements, plain weave was used as the weaving structure, and weaving was performed so that the weaving density was 60 warp yarns/cm (including the monofilament for hook engagement elements) and 20 weft yarns/cm. At this time, the monofilament for hook engagement elements was driven in parallel to the warp yarn at a ratio of one to four warp yarns, five weft yarns were floated and sunk, and then a loop was formed at a position crossing over one weft yarn and three warp yarns. Then, the loop-formed monofilament was woven so as to float on the weft yarn by floating and sinking five weft yarns again, and return to the original space between the warp yarns while forming a loop by crossing over three warp yarns and one weft yarn.

[0071] The tape for a hook type hook-and-loop fastener woven by the above method was subjected to a heat treatment at 200°C, which is a temperature at which only the sheath component of the weft yarn is melted and the warp yarn, the monofilament for hook engagement elements, and the core component of the weft yarn are not melted. As a result, the sheath component was melted and the yarn existing in the vicinity was fused to the core component of the weft yarn. Then, one leg of the loop for hook engagement elements was cut at a height of 4/5 from the bottom of the height of the hook engagement element, and the loop was used as the hook engagement element. The obtained hook type hook-and-loop fastener had a hook engagement element density of 60 elements/cm², and the height of the hook engagement element from the surface of the base fabric was 1.8 mm.

[0072] The results of the initial engagement strength and the engagement strength after repeating 20000 times of engagement and peeling of the obtained hook type hook-and-loop fastener, and whether or not the monofilament constituting the hook engagement element at a time point of repeating 20000 times of engagement and peeling was fibrillated was observed by enlarging the hook engagement element with a microscope. The results are shown in Table 1 below. Fig. 1 shows a photomicrograph of the monofilament constituting the hook engagement element after 20000 repetitions.

[0073] As is apparent from the results shown in Table 1, the hook type hook-and-loop fasteners of the present Examples are excellent in initial engagement strength, engagement strength after repeating 20000 times of engagement and peeling, and resistance to fibrillation at a time point of repeating 20000 times of engagement and peeling. Further, it can be seen from Fig. 1 that fibrillation of the monofilament did not occur at all even after repeating 20000 times of engagement and peeling.

(Examples 2 and 3 and Comparative Examples 1 to 3)

[0074] A hook type hook-and-loop fastener was manufactured in the same manner as in Example 1 except that the blending amount of the polyester elastomer was changed to 0.5% by mass (Example 2), 5% by mass (Example 3), 0% by mass (Comparative Example 1), 0.1% by mass (Comparative Example 2), or 10% by mass (Comparative Example 3) as the monofilament for hook engagement elements used in Example 1. However, in the hook type hook-and-loop fastener (Comparative Example 3) in which 10% of the polyester elastomer was blended, a state in which the cut surface of the hook was torn off and the end was not aligned was observed. It is considered that this is because the hook yarn was cut while being stretched. With respect to the hook-and-loop fastener of Comparative Example 1, Fig. 2 shows a photomicrograph of the hook engagement element at a time point of repeating 20000 times of engagement and peeling.

[0075] Table 1 below also shows the results of the initial engagement strength and the peeling durability after performing 20000 times of engagement and peeling of the obtained loop type hook-and-loop fasteners.

Table 1

	PEE Blending Amount (mass%)	Initial Engagement Strength	Engagement Strength after 20000 times of Engagement and Peeling	Resistance to Fibrillation
Example 1	2	0.32	0.22	A
Example 2	0.5	0.34	0.16	B
Example 3	5	0.21	0.14	A
Comparative Example 1	0	0.35	0.12	C
Comparative Example 2	0.1	0.34	0.08	C
Comparative Example 3	10	0.16	0.11	A

PEE: polyester elastomer Engagement strength: peeling strength (N/cm2) measured in conformity with JIS L3416 In the table, "A" means that no fibrillation was observed at all, "B" means that whitening as a sign of fibrillation was observed in a small number of hook engagement elements, and "C" means a state in which the roots of a large number of hook engagement elements were whitened, and thin independent fibrillated fibers caused by fibrillation were observed.

[0076] From the above Table 1, it can be seen that the hook type loop-and-loop fasteners in which the polyester elastomer having a blending amount within the range specified in the present invention are excellent in both initial engagement strength and engagement strength at the time point of repeating 20000 times of engagement and peeling, and that the monofilament forming the hook engagement element is not fibrillated even after repeated engagement and peeling, and on the other hand, when the blending amount of the polyester elastomer is less than the range specified in the present invention, fibrillation occurs, resulting in a decrease in the engagement strength of the product after repeated engagement and peeling. In addition, it can be seen that when the blending amount exceeds the amount specified in the present invention, the hook engagement element easily opens its hook by light tensile force, indicating that high engagement strength is not obtained.

[0077] Further, since the hook engagement element of the hook type hook-and-loop fastener of the present invention is formed of a flexible polybutylene terephthalate-based monofilament yarn, the hook type hook-and-loop fastener has a gentle skin touch and excellent flexibility, and is extremely suitable for applications in which the hook-and-loop fastener is in direct contact with the human body, and furthermore, in terms of dyeability, fiber colors of the same color can be obtained simultaneously with fibers made of an ordinary polyethylene terephthalate-based polyester.

(Example 4 and Comparative Example 4)

[0078] A woven fabric for a hook-and-loop coexistence type fastener was prepared in the same manner as in Example 1 except that the monofilament for hook engagement elements was changed from the monofilament having a diameter of 0.14 mm to a monofilament having a diameter of 0.2 mm, the following multifilament yarn for loop engagement elements was used in place of every two monofilaments for hook engagement elements in Example 1, and two rows of loops for loop engagement elements exist adjacent to the two rows of hook engagement elements on the surface of the hook-and-loop fastener, and the multifilament yarn for loop engagement elements was formed so as to cross over one weft yarn without crossing over a warp yarn at a position where the loops for loop engagement elements were formed (Example 4).

[0079]  Further, in Example 4, a woven fabric for a hook-and-loop coexistence type fastener was prepared using a polybutylene terephthalate monofilament having a thickness of 0.20 mm in diameter, which was not blended with polyester elastomer at all, as the monofilament for hook engagement elements (Comparative Example 4).

[Multifilament Yarn for Loop Engagement Elements]

[0080] 

Multifilament yarn formed of polybutylene terephthalate (melting point: 220°C)

Total dtex and the number of filaments: 265 dtex and 7 filaments

[0081] The obtained two kinds of woven fabrics were subjected to heat treatment in the same manner as in Example 1, and the two rows of loops for the hook engagement elements were cut at the leg closer to the central portion to form the loops as the hook engagement elements. The obtained hook-and-loop coexistence type fastener had a loop engagement element density of 30 elements/cm² and a hook engagement element density of 30 elements/cm², the height of the loop engagement element was 2.5 mm, and the height of the hook engagement element was 2.0 mm.

[0082] Table 2 below also shows the results of the initial engagement strength and the engagement strength at a time point of repeating 20000 times of engagement and peeling of the obtained two kinds of hook-and-loop coexistence type fasteners. Further, the degree of fibrillation of the monofilament of the hook engagement element at a time point of repeating 20000 times of engagement and peeling was observed with a microscope. The results are shown in Table 2 below.

Table 2

	PEE Blending Amount (mass%)	Initial Engagement Strength	Engagement Strength after 20000 times of Engagement and Peeling	Resistance to Fibrillation
Example 4	2	1.46	1.21	A
Comparative Example 4	0	1.49	0.72	C

PEE: polyester elastomer Engagement strength: peeling strength (N/cm2) measured in conformity with JIS L3416 In the table, "A" means that no fibrillation was observed at all, "B" means that whitening as a sign of fibrillation was observed in a small number of hook engagement elements, and "C" means a state in which the roots of a large number of hook engagement elements were whitened, and thin independent fibrillated fibers caused by fibrillation were observed.

[0083] It can be seen from Table 2 that the hook-and-loop coexistence type fastener in which the polyester elastomer having a blending amount within the range specified in the present invention is excellent in both initial engagement strength and engagement strength at the time point of repeating 20000 times of engagement and peeling, and that the monofilament forming the hook engagement element is not fibrillated even after repeated engagement and peeling (Example 4), and on the other hand, when the polyester elastomer is not blended (Comparative Example 4), fibrillation occurs, resulting in a decrease in the engagement strength of the product after repeated engagement and peeling.

[0084] Further, since the hook engagement element of the hook-and-loop coexistence type fastener of Example 4 is formed of a flexible polybutylene terephthalate-based monofilament, the hook-and-loop coexistence type fastener has a gentle skin touch and excellent flexibility, and is extremely suitable for applications in which the hook-and-loop coexistence type fastener is in direct contact with the human body.

Claims

1. A hook-and-loop fastener comprising a base fabric having existing on a surface thereof a plurality of hook engagement elements, wherein monofilaments constituting the hook engagement elements are formed of a polybutylene terephthalate-based polyester characterised in that the polybutylene terephthalate-based polyester contains 0.2 to 8% by mass of a polyester elastomer.

2. The hook-and-loop fastener according to claim 1,
wherein,

the base fabric is a woven fabric composed of a warp yarn, a weft yarn, and the monofilament for the hook engagement elements,

the warp yarn and the weft yarn are polyethylene terephthalate-based multifilament yarns,

the weft yarn has heat fusibility,

the monofilament for hook engagement elements is inwoven into the woven fabric in parallel to the warp yarn,

the hook engagement element is formed at a position where the monofilament for hook engagement elements crosses over a plurality of the warp yarns, and

the root of the hook engagement element is fixed to the base fabric through fusion of the weft yarn.

3. The hook-and-loop fastener according to claim 2, wherein the base fabric has a plain weave structure, the monofilament for hook engagement elements is inwoven into the woven base fabric every four warp yarns in parallel to the warp yarn, and the hook engagement element is formed by allowing five weft yarns to float and sink, then crossing over three warp yarns and one weft yarn to form a loop at the crossing position, and cutting one leg of the formed loop.

4. The hook-and-loop fastener according to any one of claims 1 to 3, wherein the monofilament for hook engagement elements is a monofilament having a diameter of 0.10 to 0.23 mm.

5.  The hook-and-loop fastener according to any one of claims 1 to 4, wherein a part of the monofilament for hook engagement elements is replaced with a multifilament yarn made of polybutylene terephthalate for loop engagement elements, the multifilament yarn is inwoven into a woven fabric in parallel to the warp yarn, a loop is formed at a position crossing over one weft yarn without crossing over the warp yarn, and a loop engagement element is formed without cutting one leg of the loop, and the loop engagement element and the hook engagement element coexist on the surface of the base fabric.

Ansprüche

1. Klettverschluss, umfassend einen Grundstoff mit einer auf einer Oberfläche davon vorhandenen Mehrzahl von Hakeneingriffselementen, wobei Monofilamente, die die Hakeneingriffselemente bilden, aus einem Polyester auf Polybutylenterephthalatbasis gebildet sind, dadurch gekennzeichnet, daß der Polyester auf Polybutylenterephthalatbasis 0,2 bis 8 Massen-% eines Polyesterelastomers enthält.

2. Klettverschluss nach Anspruch 1, wobei

der Grundstoff ein gewebter Stoff ist, zusammengesetzt aus einem Kettgarn, einem Schussgarn und dem Monofilament für die Hakeneingriffselemente,

das Kettgarn und das Schussgarn Multifilamentgarne auf Polyethylenterephthalatbasis sind,

das Schussgarn wärmeschmelzbar ist,

das Monofilament für die Hakeneingriffselemente parallel zum Kettgarn in den gewebten Stoff eingewebt ist,

das Hakeneingriffselement an einer Stelle ausgebildet ist, an der das Monofilament für Hakeneingriffselemente eine Mehrzahl der Kettgarne überkreuzt, und

die Wurzel des Hakeneingriffselements durch Verschmelzen des Schussgarns am Grundstoff befestigt ist.

3. Klettverschluss nach Anspruch 2, wobei der Grundstoff eine Leinwandbindungsstruktur aufweist, das Monofilament für Hakeneingriffselemente alle vier Kettgarne parallel zum Kettgarn in den gewebten Grundstoff eingewebt ist und das Hakeneingriffselement dadurch gebildet ist, dass man fünf Schussgarne flottieren und absinken lässt, dann drei Kettgarne und einen Schussgarn überkreuzt, um an der Kreuzungsstelle eine Schlaufe zu bilden, und einen Schenkel der gebildeten Schlaufe schneidet.

4. Klettverschluss nach einem der Ansprüche 1 bis 3, wobei das Monofilament für Hakeneingriffselemente ein Monofilament mit einem Durchmesser von 0,10 bis 0,23 mm ist.

5. Klettverschluss nach einem der Ansprüche 1 bis 4, wobei ein Teil des Monofilaments für Hakeneingriffselemente durch ein Multifilamentgarn aus Polybutylenterephthalat für Schlaufeneingriffselemente ersetzt ist, das Multifilamentgarn parallel zum Kettgarn in einen gewebter Stoff eingewebt ist, eine Schlaufe an einer Stelle gebildet ist, die ein Schussgarn kreuzt, ohne das Kettgarn zu kreuzen, und ein Schlaufeneingriffselement gebildet ist, ohne einen Schenkel der Schlaufe zu schneiden, und das Schlaufeneingriffselement und das Hakeneingriffselement auf der Oberfläche des Grundstoffs koexistieren.

Revendications

1. Fermeture autoagrippante comprenant un tissu de base ayant existants sur une surface de celui-ci une pluralité d'éléments d'engagement de crochet, dans laquelle des monofilaments constituant les éléments d'engagement de crochet sont formés d'un polyester à base de polybutylène téréphtalate, caractérisée en ce que le polyester à base de polybutylène téréphtalate contient 0,2 à 8 % en masse d'un élastomère de polyester.

2. Fermeture autoagrippante selon la revendication 1,
dans laquelle

le tissu de base est un tissu tissé composé d'un fil de chaîne, d'un fil de trame et du monofilament pour les éléments d'engagement de crochet,

le fil de chaîne et le fil de trame sont des fils à multifilaments à base de polyéthylène téréphtalate,

le fil de trame a une fusibilité thermique,

le monofilament pour éléments d'engagement de crochet est intissé dans le tissu tissé parallèlement au fil de chaîne,

l'élément d'engagement de crochet est formé à une position où le monofilament pour éléments d'engagement de crochet croise une pluralité des fils de chaîne, et la racine de l'élément d'engagement de crochet est fixée au tissu de base par fusion du fil de trame.

3. Fermeture autoagrippante selon la revendication 2, dans laquelle le tissu de base a une structure d'armure unie, le monofilament pour éléments d'engagement de crochet est intissé dans le tissu de base tissé tous les quatre fils de chaîne parallèlement au fil de chaîne, et l'élément d'engagement de crochet est formé en permettant à cinq fils de trame de flotter et cueillir, puis croisant trois fils de chaîne et un fil de trame pour former une boucle à la position de croisement, et couper une jambe de la boucle formée.

4. Fermeture autoagrippante selon l'une quelconque des revendications 1 à 3, dans laquelle le monofilament pour éléments d'engagement de crochet est un monofilament ayant un diamètre de 0,10 à 0,23 mm.

5. Fermeture autoagrippante selon l'une quelconque des revendications 1 à 4, dans laquelle une partie du monofilament pour éléments d'engagement de crochet est remplacée par un fil à multifilaments réalisé en polybutylène téréphtalate pour éléments d'engagement de boucle, le fil à multifilaments est intissé dans un tissu tissé parallèlement au fil de chaîne, une boucle est formée à une position croisant un fil de trame sans croiser le fil de chaîne, et un élément d'engagement de boucle est formé sans couper une jambe de la boucle, et l'élément d'engagement de boucle et l'élément d'engagement de crochet coexistent sur la surface du tissu de base.

Drawing