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EP-4735680-A1 - CONTROLLED TENSION FABRIC AND A METHOD OF MAKING SAME

EP4735680A1EP 4735680 A1EP4735680 A1EP 4735680A1EP-4735680-A1

Abstract

A controlled tension fabric (100) is provided comprising a membrane (10) including knitted fabric or woven fabric with weft and warp, and at least one yarn (1) bound to the membrane (10) and including a first filament (2) including elastic material, a second filament (3) wound around the first filament (2) with a predetermined pitch or developing parallel to said first filament (2) and including heat-shrinkable and/or water-shrinkable material defining, when subjected respectively to a heat source or a water dosage sufficient to shrink the second filament (3), a second maximum plastic linear expansion, and wherein the first filament (2) is pre-tensioned and defines a first elastic linear expansion stably maintained at least until the second filament (3) is subjected to the heat source and/or water dosage.

Inventors

  • FRITZE, TORSTEN

Assignees

  • DV8 ID S.r.l.

Dates

Publication Date
20260506
Application Date
20240627

Claims (15)

  1. 1. The controlled tension fabric (100) comprising: - a membrane (10) including knitted fabric or woven fabric with weft and warp, and - at least one yam (1 ) bound to said membrane (10) and including: - a first filament (2) including elastic material, - a second filament (3) wound around said first filament (2) with a predetermined pitch or that develops parallel to said first filament (2) and including heat-shrinkable and/or water-shrinkable material defining, when subjected respectively to a heat source or a water dosage sufficient to shrink said second filament (3), a second maximum plastic linear expansion, or and characterized by the fact that - said first filament (2) is pre-tensioned and defines a first elastic linear expansion stably maintained at least until said second filament (3) is subjected to said heat source and/or said water dosage.
  2. 2. A fabric (100) according to claim 1 , wherein said yam (1 ) is woven into said membrane (10) or English-hooked on a face of said membrane (10) or loop wrapped to one or more filaments of said membrane (10) or tubular with drop-needle stitch weave at a face of said membrane (10).
  3. 3. A fabric (100) according to any preceding claim, wherein said yam (1 ) is integrally bound to opposite ends of said membrane (10) at respective opposite ends.
  4. 4. A fabric (100) according to any preceding claim, wherein said first filament (2) is made of said elastic material.
  5. 5. A fabric (100) according to any preceding claim, wherein said elastic material is silicone.
  6. 6. A fabric (100) according to any preceding claim, wherein said second filament (3) is made of said heat-shrinkable and/or water-shrinkable material.
  7. 7. A fabric (100) according to any preceding claim, wherein said first elastic linear expansion is equal to the maximum elastic linear expansion that can be imposed on said first filament (2) in the absence of said heat source and/or said water dosage.
  8. 8. A fabric (100) according to any preceding claim, wherein said second filament (3) is configured so that said second maximum plastic expansion imposes on said first filament (2) a length variation equal to the first elastic linear expansion when said yam (1 ) is subjected to said heat source and/or said water dosage.
  9. 9. The chair defining a backrest and a seat and comprising at least one frame (101 ) and a fabric (100) according to any preceding claim.
  10. 10. The method for making a controllable tension fabric (100) and comprising: - winding or arranging parallel a second filament (3) including heat-shrinkable and/or water-shrinkable material defining, when subjected to a heat source and/or a water dosage sufficient to shrink said second filament (3), a second maximum plastic linear expansion around or parallel to a first filament (2) including elastic material with a predetermined pitch so as to create a yarn (1 ), - binding said yarn (1 ) to a membrane (10) including knitted fabric or woven fabric with weft and warp and characterized by the fact that it further comprises - pre-tensioning said first filament (2) to define a first elastic linear expansion before said winding and stably maintaining said first elastic linear expansion at least until said yam (1 ) is bound to said membrane (10) and said second filament (3) is subjected to said heat source and/or said water dosage, - removing said pre-tensioning to cancel said first elastic linear expansion.
  11. 11. The method according to claim 10, wherein in said binding phase said yam (1 ) is woven into said membrane (10) or English-hooked on a face of said membrane (10) or loop-hooked around one or more filaments of said membrane (10).
  12. 12. A method according to any of claims 11 -12, further comprising: - covering at least said first filament (2) with a layer (4) configured to maintain said first elastic linear expansion while said first filament (2) is tensioned, and - dissolving said layer (4) after binding said yam (1 ) to said membrane (10) and before subjecting said second filament (3) to said heat source and/or said water dosage.
  13. 13. The method according to the preceding claim, wherein said layer (4) comprises a tape including polymeric material, and said covering phase is carried out by wrapping the first filament (2) tensioned with said tape.
  14. 14. The method according to the preceding claim, wherein said polymeric material is of the thermoplastic type.
  15. 15. A method according to any of claims 10-14, wherein said water dosage is at a temperature of approximately 30 °C.

Description

DESCRIPTION CONTROLLABLE TENSION FABRIC AND METHOD FOR MAKING SAID FABRIC The present invention relates to a controllable tension fabric, and the related method for making said fabric, of the type specified in the preamble of the first claim. In particular, the present invention relates to a fabric comprising a preferably knitted membrane to which a composite yam defining controllable elastic properties is bound, particularly suitable for use in making seats or backrests of chairs, such as an entire fabric surface of the seat or fabrics that generally require controlled elasticity preferably lower than the elasticity of the fabric. As is known, in recent years, the use of heat-shrinkable yarns has been widely disseminated and successful in the textile sector. Heat-shrinkable yarns are essentially composite yams that have the ability to shrink when heated; this capability is similar to the commonly used materials for heatshrink tubing. Specifically, unlike the tubing technique where the tubular element undergoes constrictions, heat-shrinkable yams are configured to reduce their length when approached by a heat source. The heat-shrinkable yam is particularly useful when introduced into the weft within a fabric, whether it is a fabric made of weft and warp or even a knitted fabric. The shrinkage capability of the yam allows, in fact, to locally tension the fabric on command so as to control the mechanical characteristics of the fabric itself in the area where the yam is woven. More specifically, generally, the heat-shrinkable yam consists of a first filament, or core, and a second heat-shrinkable filament wound around the first filament or a single composite yarn. The entire composite can also be woven in warp or weft direction. This heat-shrinkable yam has, particularly recently, been used to make knitted fabrics, wherein the yarn is uniformly knitted, to create seats or backrests of chairs that can be tensioned through the application of heat, such as in an oven or with hot steam. An example of such a fabric is marketed under the name Camira knit™. The known technique described has some significant drawbacks. In particular, when the heat-shrinkable yarn in knitting undergoes the shrinkage process, it tends to become excessively loose and, therefore, can form excessively soft areas or wrinkles in areas like the seat or backrest of a chair to which the fabric with heat-shrinkable yam is applied. Therefore, especially in the area of the backrest, the fabric does not maintain the desired shape, and it is not possible to fully control the conformation of the support areas. Moreover, a fabric that is uniform in terms of properties does not allow for the variation of its characteristics locally, that is, at specific areas. In this situation, the technical task underlying the present invention is to devise a controllable tension fabric, and the related method of making it, capable of substantially overcoming at least part of the aforementioned drawbacks. Within the scope of this technical task, an important object of the invention is to provide a controlled tension fabric, and the related method of making it, which allows complete control over the shape and tension imposed on a seat or backrest of a chair, once used on the seat or backrest of the chair. Another important object of the invention is to make a controlled tension fabric, and the related method of making it, that can support a user comfortably and effectively when used on a chair. Furthermore, an additional task of the invention is to create a controlled tension fabric, and the related method of making it, that allows for an aesthetically pleasing, uniform appearance without fractures between areas of different functionality, for example, with different applied tensions, and that presents controllable lines in the shape in which there are no wrinkles or other undesirable sagging areas. Moreover, an additional object of the invention is to create a controllable tension fabric, and the related method of making it, that allows control of the padding volume when the latter is present in relation to the tension imposed on the fabric, maintaining residual elasticity after shrinkage. In conclusion, a task of the invention is to create a controlled tension fabric that can be made entirely in a single production process. The technical task and the specified objects are achieved by a controlled tension fabric, and the related method of making it, as claimed in the attached claim 1 . Preferred technical solutions are highlighted in the dependent claims. The features and advantages of the invention are clarified below by the detailed description of preferred embodiments of the invention, with reference to the accompanying drawings, wherein: Fig. 1 shows a sequence diagram of a process for making a controllable tension fabric according to the invention; Fig. 2 illustrates a sequence diagram of the sub-phases of tensioning and covering of the pre-tensioning phase