TOUCH FASTENER TAPE

Abstract: The invention features a textile fastener tape characterized by having, in the weft direction across the tape, one or more sections of the tape being elastically stretchable and one or more sections being not stretchable as a result of the construction of the textile fabric itself. The fastener tape can be a woven or a knitted fabric.

Description: 1 - TOUCH FASTENER TAPE Background of the Invention This invention relates to touch fastener tapes, such as for hook-and-loop fastening, and methods for producing such tapes. Textile based touch fasteners tapes, i.e. tapes of woven or knit fabric, are often used in the weft, or cross machine, direction. These tapes are cut from the textile to have the lengthwise direction of the tape oriented with the weft or cross-machine direction of the textile fabric. Thus tension on the tape occurs in the weft or cross-machine direction of the textile fabric. It is desirable for touch fasteners to exhibit elasticity and to form secure fastenings for making secure closures. Summary of the Invention The invention features a textile fastener tape having its tension direction oriented with the weft direction of the textile fabric, one or more sections of the tape being elastically stretchable and one or more sections being not stretchable as a result of the construction of the textile fabric itself. In preferred embodiments the fastener tape is produced on standard weaving machines, using warp and weft yarns in which selected warp yarns are elastic and are provided in selected localized patterns in which sections of the yarns have a component of their extent in the cross machine or weft direction. Alternatively, the fastener tape is produced on knitting machines using elastic warp yarns. The resulting tapes are stretchy in the weft direction only in the sections where the elastic yearns have extent in the weft direction, other sections of the tape being non stretchable. - 2 - In a general aspect of the invention, the fastener tape includes a textile backing defining a warp and a weft direction and, in the weft direction, having a first region and second region. The first region is substantially non-stretchable in the weft direction and the second region is substantially elastically stretchable in the weft direction. In an array of fastener elements extends from a selected region of the tape. The region of the fastener tape that is substantially elastically stretchable observably increases in length in response to a typical force applied to the fastener tape and, upon removal of the force, retracts to approximately the original length of the region. A region of the fastener tape that is substantially non-stretchable does not observably increase in length in response to typical forces applied to a fastener tape. Important embodiments of this aspect of the invention include one or more of the following features. The fastener tape includes a region having fastener elements, the region being substantially non- stretchable in the weft direction, or the fastener tape includes a region having no fastener elements and which is substantially non-stretchable in the weft direction, e.g. suitable for securing to an object or the fastener tape includes at least two non-stretchable regions, one having fastener elements and one being disposed to be permanently secured to an object such as a diaper. An elastic region of the fastener tape includes a warp pattern defined by inelastic warp yarns and elastic warp yarns having a portion extending in a weft direction for crossing at least one inelastic warp yarn. Many of the elastic warp yarns each cross more than one inelastic warp yarn. The textile backing is woven. The textile backing is a leno weave. The textile backing is a knit. The fastener tape is in the form of a fastener tab having a portion secured to an object and a portion protruding beyond the object having the second region with the fastener elements spaced from the object by the second region. The object is a garment (e.g. a diaper) . The fastener tape is formed by first forming a textile fabric having a weft direction by knitting or wearing, the fabric having bands extending in the weft direction, at least one of the bands being stretchable in the weft direction, and one of the band not being stretchable, and then forming the tape from a portion of the fabric, the tape extending in the weft direction of the fabric and including portions of a stretchable and a non-stretchable band. Other features and advantages will be apparent from the following description and claims. Brief Description of the Drawings Fig. 1 is a plan view of a fastener tape. Fig. 2 is a schematic illustration of a fabric from which the fastener tape is cut. Fig. 3 is a side view of the fastener tape of Fig. 1. Fig. 4 illustrates the structure of an elastic section of a woven fastener tape . Figs. 5A and 5B show the elastic section structure of a woven fastener tape under tension and relaxed, respectively. Fig. 6 illustrates the structure of an elastic section of a knit. Fig. 7 shows the fastener tape on a diaper. - 4 - Description Referring to Figs. 1 and 2, a textile fastener tape 2 includes a fastener section 4, an elastic section 6, and a tab section 8 arranged sequentially across a length 10 extending in weft direction 12 of the textile fabric 14 from which the tape is cut. Sections 4, 6, 8 exhibit different elastic behavior in weft direction 12, being, non stretchable, stretchable, and non stretchable, respectively, as a result of the pattern of construction of the textile fabric. In response to a typical applied force along weft direction 12 of the fastener tape, fastener section 4 and tab section 8 do not substantially stretch while elastic section 6 observably stretches. Referring to Fig. 2, fastener tape 2 (Fig. 1) is produced from fabric 14 which includes multiple fastener sections 4, elastic sections 6, and tab sections 8 that extend as continuous bands in warp direction 16 of the fabric, as it is formed. A portion of fabric 16 as indicated by dotted line 18 is cut to form the fastener tape 2 of Fig. 1, the lengthwise direction 12 of the tape extending in the weft direction 12 of the textile fabric. Referring to Fig. 3, an array of male fastener elements 20 extends from a base fabric 22 of fastener tape 2 for the purpose of engaging cooperating fastener elements to make a closure. Male fastener elements 20 can be hook-shaped, as shown, or mushroom-shaped. In either case, the fastener elements can be formed by cutting loops of the formed textile by techniques well-known in the touch fastener art. For instance loops of monofilament yarns have portions cut away to form loop-engageable fastener hooks or ends of cut loops of monofilament are deformed by heat to form loop-engeagable mushroom heads. In other cases multiple yarn loops form hook-engageable fastener loops. - 5 - Referring to Fig. 4, elastic section 6 is manufactured by incorporating a number of elastic warp yarns 24 into a woven fabric 26 being woven primarily of inelastic warp yarns 28 and in elastic weft yarns 30. The selected weaving pattern causes elastic warp yarns 24 to have weft direction components of extension in section 6, see Fig. 2. Here, localized sections 32 of warp yarns extend in weft direction 34, though the overall direction of extent of these yarns is in warp direction 36. As in a leno weave, elastic warp yarns 24 cross adjacent inelastic warp yarns 32. In some cases, individual elastic warp yarns 24 cross over multiple inelastic warp yarns 28. Examples of elastic warp yarn 24 include elastomeric yarn (110 decitex) , either single-component or coated, and lycra (235 decitex) coated with nylon. Elastic section 6 is formed to have a density of approximately seventeen elastic warp yarns 24 per one inch width fabric. In some cases, it is desirable to produce woven fabric 26 having multiple elastic sections 6 with different elastic properties (e.g. different elongations) . Referring to Fig. 5A, a cross-section of a portion of elastic section 6 is placed under tension by a force, indicated by arrows 40, in weft direction 34. The force, for example, is applied during the weaving process used to manufacture fastener tape 2 and causes elastic warp yarns 24 to stretch in weft direction 34 while being incorporated into fabric 26 (Fig. 4) . Alternatively, the force can be applied to fastener tape 2 in use. Elastic warp yarns 24 elastically elongate in response to the force. Referring to Fig. 5B, when the force is removed elastic warp yarns 24 contract and elastic section 6 returns to an unstretched state. Woven fabric 26, in the - 6 - region where the elastic yarns are incorporated in the weave pattern forms a wave-like structure as the inelastic warp yarns 32, crossed by elastic warp yarns 24 (Fig. 4) , are pulled in by the contraction. Referring to Fig. 6, in a knitted construction following the same principles, section 6 of a knitted fabric 48 includes a series of wales 46, that is rows of loops of inelastic yarns that extend across knitted fabric 48, in between which elastic weft yarns 44 and inelastic weft yarns 42 are knitted in respective sections of the textile fabric corresponding to sections 6 in FIGS 1 and 2. Elastic weft yarns 44 and inelastic weft yarns are knitted in between two non-adjacent wales 46 such that at least one wale 46 is common to both elastic weft yarn 44 and inelastic warp yarn 42. Because of the extensibility in weft direction 50 of elastic weft yarns 44, elastic section 6 elastically stretches in response to a force applied to knitted fabric 48 in weft direction 50, as described with respect to woven fabric . Other knitting patterns having different types of interlacing between elastic yarns 44 and inelastic yarns 42 may be employed to effect the elasticity of elastic section 6. Referring to Figs. 1 and 7, fastener tape 2 is permanently adhered at its tab section 8 to a garment and used to secure the garment, in this case, diaper 52, around a human body. In use, fastener tape 2 is pulled in the weft direction 12 to engage male fastener elements 20 (Fig. 3) of fastener section 4 with female fastener elements (not shown) on an opposite side of garment 52. As fastener tape 2 is pulled, elastic section 6 stretches in the weft direction while fastener section 4 and tab section 8 do not stretch. The non-stretchability of the respective sections 4 and 8, contribute to the - 7 - performance of the fasteners of section 4 and the strength of the bond of section 8 to the garment. After fastener elements 14 are correspondingly engaged, the tendency for elastic section 6 to return to its unstretched state provides a force that secures diaper 52 around the body and helps to maintain the engagement of the closure. Other features and embodiments are also within the scope of the following claims.

Claims: - 8 - What is claimed is: 1. A fastener tape (2) comprising: a textile backing formed by a pattern of selected yarns defining a warp direction and a weft direction, the textile backing (14) , as a result of the pattern of selected yarns, having, in the weft direction (12) , a first region (4 or 8) that is substantially non- stretchable in the weft direction and a second region (6 ) that is substantially elastically stretchable in the weft direction. 2. The fastener tape of claim 1 in which an array of fastener elements (20) extend from the first region (4) . 3. The fastener tape of claim 1 or 2 having fastener elements in the form of hook-engageable hooks (20) . 4. The fastener tape of any of the foregoing claims wherein the textile backing includes at least two non-stretchable in the weft direction, regions (4,8), one of which carrying fastener elements and one of which having no fastener elements. 5. The fastener tape of claim 4 in which one of the non-stretchable regions (4) carries an array of fastener elements and the other non-stretchable region comprises a tab arranged to be joined to an article, e.g., an article of clothing such as a diaper. 6. The fastener tape of any of the foregoing claims wherein the elastically stretchable region includes a warp pattern defined by inelastic warp yarns and elastic warp yarns, the elastic warp yarns each - 9 - having a portion extending in a weft direction for crossing at least one of the inelastic warp yarns. 7. The fastener tape of claim 6 wherein the textile backing is woven and comprises a leno weave (FIG. 4) . 8. The fastener tape of claims 6 or 7 wherein many of the elastic warp yarns each cross more than one inelastic warp yarn. 9. The fastener tape of any of the claims 1-6 wherein the textile backing comprises a knit (FIG. 6) . 10. The fastener tape of any of the foregoing claims in the form of a fastener tab having a portion secured to an object and a portion protruding beyond the object, the protruding portion having a stretchable region and a second region from which fastener elements extend, the second region being spaced from the object by said stretchable region. 11. The fastener tape of claim 10 wherein the object comprises a garment. 12. The fastener tape of claim 11 wherein the garment comprises a diaper. 13. A method of forming the fastener tape of any of the foregoing claims characterized in forming a textile fabric (14) having a weft direction (12) by knitting or weaving, the fabric having bands extending in the warp direction (16) , at least one of the bands (6) being stretchable in the weft direction, and one of the bands (4 or 8) being non-stretchable, and forming the 10 - tape from a portion (18) of the fabric, the tape extending in the weft direction of the fabric and including portions of a stretchable and a non-stretchable band. 14. The method of claim 13 further characterized in forming an array of fastener elements (20) in one of said non-stretchable bands (4 or 8) . 15. The method of claim 13 further characterized in forming in the stretchable bands (6) a warp pattern defined by inelastic warp yarns and elastic warp yarns, the elastic warp yarns each having a portion extending in the weft direction for crossing at least one of the inelastic warp yarns. 16. The method of claim 15 characterized in that the elastic warp yarns each cross more than one inelastic warp yarn. 17. The method of claim 13 further characterized in that the fastener tape has a non-stretchable portion secured to an object and a portion protruding beyond the object, the protruding portion having a stretchable region and a non-stretchable region from which fastener elements extend, the non-stretchable region being spaced from the object by the stretchable region.

Inventors: CLERICI PIERO RUSCONI, COSLOVI GIULIANO, CLERICI, PIERO, RUSCONI, COSLOVI, GIULIANO
Applicants: CLERICI PIERO RUSCONI, COSLOVI GIULIANO, VELCRO IND, CLERICI, PIERO, RUSCONI, COSLOVI, GIULIANO, VELCRO INDUSTRIES B.V.
Application year: 1999
Main classification: A44B18
IPC codes: A44B18, A61F13