AU2544000A - Elastic insert, method for the production and use thereof - Google Patents

Description

WO 00/45657 PCT/EPOO/00546 Elastic Insert, Method for the Production And Use Thereof The present invention relates to an elastic insert, a method for the production and use thereof. For many years, inserts have been used in the garment industry, mainly for reinforcing the front parts of clothing. These inserts consist of a substrate which may be formed as a woven fabric, knitted fabric or as non woven fabric, and of a generally thermoplastic adhesive mass applied in the form of a grid, with this adhesive paste enabling a glueing with the outer fabric of the piece of clothing. The purpose of such inserts is to give the clothing item shape and to stabilize it. Due to their being bonded with the outer fabric, they influence the character of the finished clothing piece in a decisive manner. The look, shape stability, softness, wear comfort as well as the care properties in dry-cleaning and laundry depend decisively on the kind and structure of the inserts used. Particularly important properties of the items of clothing are the look, feel and care property of the finished clothing item. In addition, the clothing must be in line with the changing fashions. For this reason, various differing outer fabrics are employed. Accordingly, as a rule, different kinds of inserts are also used to reinforce these various outer fabrics. Conventionally, staple fiber yarns of viscose (CV), cotton _CO), polyester (PES), polyacrylonitrile fibre (PAN) or 2 mixtures thereof are used for traditional inserts on the basis of woven fabric. The fineness of the yarns used is as a rule in the range of 10 to 200 Nm. The weight of these inserts ranges usually from 35 to 140 g/m 2 . The woven fabrics thus produced are either crosslinked by means of cellulose crosslinking agents or thermally stabilized by shrinking. By shagging or emerizing one side of the fabric, a fiber pile as dense as possible is created on the surface of the insert and thus a high degree of softness and volume as well as density of the insert is attained. This is of decisive significance for the feel of the finished piece. The non-shagged side of the fabric is then coated with an adhesive mass, preferably hot-melt adhesive, according to known methods. When glueing the insert with the outer fabric, the fiber pile on the rear side prevents in addition a penetration of the hot-melt adhesive through the insert in the direction of the side of the lining. Similar inserts are also generally known as knitted fabrics. In the weft, use is made of the afore-mentioned staple fiber yarns of CV, CO, PES, PAN or mixtures thereof. As a rule, the warp is formed of fine filament yarns consisting preferably of polyester or polyamide and having a fineness in the range of 25 dtex to 78 dtex. In this case, the side which is not coated with hot-melt adhesive is also shagged to attain a soft feel and a high volume and prevent the coating from seeping through the insert. Non-woven fabrics are also used as substrate materials for inserts. The weight of such inserts used for cementing the front of pieces of clothing ranges normally from 20 to 80 g/m 2 . As a rule, hardening takes place thermally by engraved calendar rolls. Often, the non-woven fabrics are additionally reinforced by warp threads and/or weft threads which may be knitted in. These yarns consist 3 likewise of the above-mentioned fine filament yarns or of textured polyester filaments. These non-woven fabrics may be coated with hot-melt adhesives. Due to the character of the non-woven fabrics, the risk of the coating seeping through the outer fabric is normally low. However, a disadvantage of this type of inserts is that they do not have the volume and the soft feel of the above shagged inserts. European Patent EP-A-0 810 314 proposes another type of rigid inserts made of air-bulked yarns to maintain volume and soft feel. Similarly to the methods known from the finishing of plush, use is made of woven fabrics and knitted fabrics having loops. These loops result when using air-bulked PES yarns. Yarns produced in accordance with this special texturing method consist of two thread systems. A core thread ensures stability. The loops made of air-bulked PES effect yarns finish the look of the fabric and provide the soft feel. The yarns of the resulting inserts are not elastic. In addition, the structure of the loops causes entanglements of the lengths of material. Furthermore, such an unsteady and uneven surface can hardly be coated with the most common method of coating for cement inserts, i.e. the paste scatter double point method. Therefore, further processing of the loops is necessary in order to obtain a uniform fabric surface. Said loops are, as has long been known from other areas of textile finishing, straightened and opened mechanically by shagging, emerizing or brushing, or burnt off by singeing. However, exactly the process of singeing the loops poses serious problems as regards the safeness of the process. Discoloration of the textile fabric may occur. In addition, the feel is hardened by singeing balls resulting at the fiber ends. This may lead to the necessity of 4 further post-treatments. Moreover, these further operational steps such as singeing or emerizing result in additional costs. As a whole such inserts have not been able to be established on the market. All of the above-described inserts have in common that they are largely stiff and have low elasticity in the longitudinal and traverse directions when stretched. The insert may exhibit low expandability when subject to high mechanical strain. However, this expansion does not completely revert after strain of the insert. This lack of elasticity of the known inserts constitutes a considerable disadvantage. When cementing such a known insert with an outer fabric, the insert is not capable of following the alteration of the dimensions of the outer fabric caused by heat, laundry, solvents used during dry-cleaning, or by external forces, which can cause on the finished piece of clothing the formation of wrinkles, a partial separation of the insert or also wave-like deformations and bulges. The user value of the piece of clothing is strongly impaired by this. This problem is especially serious in modern mono- or bi-elastic outer fabrics which are subject to enormous alterations of dimensions due to their proportions of elastan during cementing and steaming. If it is now attempted to avoid the separations and to increase the adhesive power by an increased amount applied of the adhesive mass, the adhesive can penetrate during cementation of the insert with the outer fabric through the insert and/or the outer fabric. Not only will the cementing press of the clothing manufacturer be dirtied by this means and the perfect step of cementing destroyed by swatch parts adhering to each other, but the feel and thus the value of the piece of clothing are greatly reduced by this also.

5 Since for this reason the amount of adhesive mass to be applied cannot be increased, the attempt is made to adapt the insert to the respective outer fabric in view of its shrinkage behaviour. This is, however, almost impossible in practice for the clothing industry since very many different types of outer fabric with greatly varying properties are processed and the clothing industry is, however, forced for economical reasons to cover the entire scope of outer fabrics with as few types of inserts as possible. Moreover, a satisfying cementing result cannot be obtained with this kind of rigid insert on elastic outer fabrics since the properties of insert and outer fabric are too different. In order to avoid these disadvantages, another kind of cement insert was developed in the last few years. These are characterized by the use of false-twist textured polyester filament yarns with a fineness of 20 to 400 dtex as weft threads. The warp can be structured similarly as is already given above with the known rigid inserts, it can, however, also be produced from textured polyester yarns with a fineness of between 25 and about 167 dtex. Such an insert is described in DE 93 198 70 U1. The woven or knitted substrate is also coated with hot-melt adhesive according to known methods. The weight of this insert is usually between 35 and 120 g/m 2 . The properties of the cement inserts are characterized in varying degrees by the properties of the false-twist textured polyester filament yarns. These false-twist textured polyester filament yarns are to a great degree elastic because they expand very easily during stretching in warp and weft direction just as in slanting-off. After the end of the stretching, these yarns revert almost completely to their original condition. The elasticity in the weft direction usually amounts to 20 to 25%, can, however, be increased to up to 40%. In the warp 6 direction, the elasticity is ideally 6 to 8%. Elasticity values of up to 15% are also known, however, increased effort is necessary to attain this high elasticity value in the processing by the clothing industry. The inserts are capable, due to their elasticity, to follow exactly the changes in dimension of the outer fabric caused by heat, during laundering, by solvents during dry-cleaning or by external forces. The disadvantages listed above of the rigid, shagged inserts are thus avoided. This kind of inserts can therefore be used almost universally on many different kinds of outer fabrics, especially if they consist in warp and weft of textured polyester yarns. A high volume also results due to the crimping of the textured polyester yarns, which prevents the hot-melt adhesive from seeping through the insert back in the direction of the lining side during cementing with the outer fabric. Textured polyester yarns are also used in combination with a non-woven fabric. Such an insert is described in DE 44 08 813 C1. The elasticity of the knitted non-woven composite is guaranteed by a steaming process at least in the warp direction. The main task of the reinforcing threads of textured polyester yarns or bi-component filament yarns is to generate the desired elasticity and to simultaneously prevent destruction of the non-woven fabric during stretching. This kind of inserts, however, do show the disadvantage that the textured polyester filament yarns or bi-component filaments cannot be shagged because there are no fiber ends with filaments available for shagging. For this reason, the appearance of the feel of the insert cannot 7 attain the soft feel and the elegance of a rigid shagged insert. Gradual improvements were obtained by the use of textured micro-fiber yarns which should allow a softer feel due to the fineness of the individual filaments (cf. EP 0481867 Al). Complicated structures are also known from e.g. EP 0 289 378 Al which in addition to warp and weft consisting each of textured polyester yarns introduce a third thread system consisting of shagged, non-elastic yarns as are used also in classic, shagged inserts. By this means, however, the looks of a rigid shagged insert are not attained since the basic problem still exists, i.e. that the elastic thread systems can still not be shagged. For this reason, the appearance of the feel of this elastic cement insert and the finished piece of clothing is found especially by high-class fashion circles to be in comparison with classic shagged inserts too synthetic, dry and artificial. In DE 196 44 111, the use of multi-component fibers of the side-by-side type are proposed to solve this problem. The problems of feel are solved by this. However, these fibers are expensive and are available world-wide only in small amounts in very fine fiber titres (single filament titer < 2dtex), which are necessary for an especially soft feel. Thus, a broad commercial use of inserts of such fibers is not possible at this time. Furthermore, the dimensional stability of these inserts with outer fabric materials of all kinds is still not satisfactory. The object of this invention is to develop elastic inserts capable of being competitive in costs, which combine the low shrinkage values and easy to care properties of inserts of false-twist textured polyester filament yarns with the soft feel of a classic, shagged insert.

8 Moreover, a method for the production of such an insert as well as especially favorable uses are given. This succeeds surprisingly by use of commercially common filament yarns, with the elastic inserts produced from such filament yarns being shagged especially by emerizing. Preferred embodiments of the insert according to the invention are given in claims 2 to 8. This invention describes moreover a method for production of an elastic insert with the features of claim 9. False-twist textured polyester (PES) and/or polyamide (PA) yarns are preferably used as filament yarns. False-twist textured polyester yarns have long been known in the production of inserts. The false-twist texturing generates high elastic threads with high expansion and great fluff volume. These yarns can also be incorporated as heretofore in a fabric, knitted fabric or knitted fabric with weft insertion. With conventional manufacturing and finishing the elastic inserts mentioned above result which often feel, however, dry and synthetic to the touch since the filament character determines the feel. The inserts produced according to the invention comprise in contrast thereto the same elasticity, but have at the same time the soft, fluffy feel of classic inserts. This is possible by the finishing method described in the present invention in which the part imparting feel of the false-twist textured filaments is mechanically destroyed and thus many projecting fibers develop which allow the development of the look and feel of a shagged insert of fiber yarns.

9 The textile substrate on which the present invention is based can be a woven fabric, knitted fabric or knitted fabric with weft insertion and comprises a weight of preferably 15 g/m 2 to 125 g/m 2 . At least the weft or the warp, more preferably warp and weft, consist preferably of false-twist textured PES or PA filament yarns. The yarn fineness of the false-twist textured PES or PA filament yarns is commonly between dtex 15 and dtex 440, more preferably between 30 and 180 dtex. In fabrics, the kinds of bonding common in all cement inserts can be used, such as linen weave, cross twill 2/2, cross twill 3/1 or satin. However, the variants which are especially suitable are those in which the false-twist textured yarns are in float stitches. In knitted fabrics or knitted fabrics with weft insertion, the binding methods also well known can be further used. The gray fabrics manufactured by this means are subject, as is usual, to a laundry and shrinking process. Contraction of the yarns and desired maximum elasticity can be attained by heat and moisture. Thereafter, if necessary, a dying process and the thermo-stabilization are performed on a stretcher. The concluding step is to coat these products according to the usual coating method with an adhesive, preferably with a thermo-plastic hot melt adhesive or with a reactive coating mass. The application can take place as a grid, with the grid being able to have between 1 mesh and 35 meshes. In order to attain the feel effect of a shagged classic insert as according to the invention, an additional mechanical finishing process, shagging, is introduced, preferably emerizing.

10 The emerization as appret effect is used especially in the production of suede imitations and ''peach skin'' finishing on fabrics and knitted fabrics. The emerization is a variation of shagging and is performed on an emerization machine. The surface of the length of goods is shagged on purpose during passage through this machine by rubbing on one or more emerization rollers. The material thus receives a velvet-like character which can be controlled by the use of various kinds of emory paper. The emory paper consists preferably of a flexible substrate such as paper, latex paper, woven fabric, foils, non-woven fabric or combination fibers with abrasive granulars distributed evenly therethrough and is wound up in spiral form onto the at least one emory roller. These rollers can be driven independent of each other and arbitrarily abrase with or counter the direction of movement of the material. Alongside of the direction of rotation of the rollers, the stretching of the material and speed of movement of the material, the abrasion process can be influenced by the kinds of granulars used in the abrasive paper as well as the graining. In practice, the following common kinds of granulars are used: silicone carbide, aluminum oxide, circon corundum, ceramics and diamond. The graining is determined by the amount of granulate per surface unit and can lie in the range of 40 to 1,000, with a graining being preferably used in the material described according to the invention in the fine range of 100 to 500. The abrasion of the granulate causes a splicing open of the fiber ends on the surface of the material and thus imparts to this a velour-like character. Such a shagged insert is surprising for the person skilled in the art insofar as that with filaments neither fiber 11 ends - as in the staple fiber yarns of the classic insert article - nor loops - as in pile articles with special material construction or with air-bulked yarns - are available which can be emerized or made to stand up. Rather, the fiber ends necessary for a soft and rough feel must first be generated in that the filaments are torn apart at many places. Many filaments must be destroyed here in order to create a pile with projecting fiber ends which is as thick and uniform as possible. First, there is a homogenous fiber system in which all of the individual filaments contribute equally to the stability of the thread. In contrast to air-bulked PES yarns or pile articles, no additional thread system (core threads) are present in the false-twist textured PES yarns, which establish stability. For this reason, any destruction of a filament causes loss of strength. Commercially common false-twist textured yarns comprise as a rule no twist or only a minimal twist (between 0 and 20 T/m) and therefore the destroyed filaments fray and can leave the substrate as loose fibers. According to the invention, the shagging step can be performed in various steps of the method. If the shagging (emorization) step takes place after the coating with the adhesive, some coating mass penetrates into the threads of the insert and thus causes an additional stabilization. This is surprisingly also the case if the emorized side is opposite the coated side. The tendency to fray is minor since the coating mass, even if it lies on the opposite side, causes an additional stability. The individual fibers adhere in part to each other due to the residue of coating mass. Moreover, not all filaments are completely cut through by the shagging step and therefore there is sufficient residue strength.

12 The inserts produced by this means comprise excellent volume and are especially preferred according to the invention. If the tear strength of the fibers is to be further improved and the tendency to fray reduced even further, false-twist textured yarns can be used comprising in addition a twist. The twist can amount to 20 T/m to 1,000 T/m, it lies, however, preferably at 100 T/m to 400 T/m. After the emorization process, fibers result here also where one end is, however, cemented in the yarn due to the twist. The volume of the article is lesser with equal article construction, the greater the yarn twisting. The shagging or emorization step can, however, also be performed before the coating with adhesive or during the pre-treatment. In this case, care should be taken that no stringing or disarrangement of the threads occur. With the insert according to the invention a thermo plastic hot-melt adhesive is preferably used and applied in grid fashion. A hot-melt adhesive on the basis of (CO)polyamide, (CO)polyester or polyethylen is especially preferred. The application weight is generally 8 to 15 g/m 2 , preferably 9 to 12 g/m 2 . Hereinafter, a few especially preferred embodiments of the emorized insert according to the invention are given as illustration of the invention. The emorization machine given in the following examples is a solid-roller emorization machine. Alongside of solid roller emorization machines, lattice roller emorization machines are known in the field. These lattice rollers support individual emorization cover-strips mounted parallel to each other and are suited especially for thick voluminous materials with natural fiber proportions. A 13 further variant is the napping machine in which the rollers are wound with a wire clothing and can produce an essentially thicker fiber pile. Example 1: Woven Fabric Warp: PES textured HE intermingled dtex 100f36/1 Weft: PES textured HE dtex 100f32/2 Weft density: approx. 140 Fd/10 cm Bond: cross twill 1/3, this non-simultaneous bond generates weft floats, the material is emerized on the weft side. Total weight: approx. 60 g/m 2 Coating: 11 g/m 2 polyamide hot-melt adhesive Operational steps in the final finishing: - shrinkage - finishing - coating - emerization - steaming Emerization passages: 1st roller graining 320 twist direction: as material moves 2nd-4th roller graining 400 twist direction: as material moves Rate of material: 10 m/min Number of passages: 1 Type of machine: Sperotto Rimar SM4 14 Example 2: Raschel Knitting Machine Warp: PES smooth dtex 33f15/1 Weft: PES textured HE dtex 100f72/2 Protective twist: T/m = 200 Weft density: approx. 120 Fd/ 10 cm Bond: Closed frays Total weight: approx. 30 g/m 2 Coating: 10 g/m 2 polyamide hot-melt adhesive Operational steps in the final finishing: - shrinkage - finishing - emerizing - coating - steaming Emerization passages: 1" and 3 rd rollers graining 400 twist direction: as material moves 2 nd roller graining 400 twist direction: counter movement of the material Rate of material: 12 m/min Number of passages: 1 Type of machine: Sperotto Rimar SM4 Example 3: Raschel Knitting Machine Warp: PES textured HE dtex 33f15/1 Weft: PES textured HE dtex 167f100/2 Weft density: approx. 100 Fd/ 10 cm 15 Bond: Staggered frays Total weight: approx. 45 g/m 2 Coating: 9 g/m 2 polyamide hot-melt adhesive Operational steps in the final finishing: - shrinkage - finishing - coating - emerizing - steaming Emerization passages: 1 s' and 2 d roller graining 400 twist direction: as material moves 3 roller graining 500 twist direction: counter movement of the material Rate of material: 14 m/min Number of passages: 1 Type of machine: Sperotto Rimar SM4 Example 4: Woven Fabric Warp: PES textured HE intermingled dtex 100f36/1 Weft: PES textured HE dtex 167f32/2 Weft density: approx. 115 Fd/10 cm Bond: cross twill 2/2 Total weight: approx. 80 g/m 2 Coating: 10 g/m 2 polyamide hot-melt adhesive Operational steps in the final finishing: 16 - shrinkage - finishing - emerizing - coating - steaming Emerization passages: 1 't and 2 "d rollers graining 320 twist direction: as material moves 3rd roller graining 400 twist direction: as material moves Rate of material: 12 m/min Number of passages: 1 Type of machine: Sperotto Rimar SM4 As the application examples reveal, this emerization process can be performed at various positions in the chain of production. For the first time, it is thus possible with conventional false-twist textured yarns to generate the look and feel of a classic shagged insert and to combine these properties with the advantages of the elastic insert.

Claims (18)

1. Elastic inserts consisting of a substrate on the basis of a woven fabric, a knitted fabric or a knitted fabric with weft insertion, with the material of the warp and weft thread being a filament yarn, and having an adhesive layer and having an adhesive layer applied to one side of this substrate, characterized in that the insert is shagged on the side that is not provided with the adhesive.

2. Insert according to claim 1, characterized in that the filament yarn is produced from polyester and/or polyamide.

3. Insert according to claim 1 or 2, characterized in that the filament yarn has a yarn fineness ranging from 15 dtex to 440 dtex.

4. Insert according to one of the claims 1 to 3, characterized in that the filament yarn has a yarn fineness in the range of 30 dtex to 180 dtex.

5. Insert according to one of the claims 1 to 4, characterized in that warp thread and/or weft thread consist of false-twist textured polyester or polyamide filament yarns.

6. Insert according to one of the claims 1 to 5, characterized in that the filament yarns comprise in addition a twist.

7. Insert according to claim 6, characterized in that the twist lies in the range of 20 to 1,000 T/m. 18

8. Insert according to claim 6 or 7, characterized in that the twist is in the range of 100 to 400 T/m.

9. Method for the production of an elastic insert of a substrate on the basis of a woven fabric, knitted fabric or knitted fabric with weft insertion, with the material of the warp thread and/or weft thread being a filament yarn, and with an adhesive layer applied to one side of the substrate, by: (a) production of a gray woven fabric, a gray knitted fabric optionally with weft insertion of filament yarns, (b) optionally performing a dying step, (c) thermo-stabilization of the gray woven fabric or knitted fabric, (d) coating one side of the obtained gray woven fabric or knitted fabric with an adhesive, characterized in that as a further step a shagging is performed with the surface not provided with adhesive.

10. Method according to claim 9, characterized in that the shagging takes place by emorization.

11. Method in accordance with claim 10, characterized in that for the emorization an emorization paper is used which is wound like a spiral onto at least one emorization roller, with the surface of the insert being shagged by rubbing on this at least one emorization roller.

12. Method according to claim 11, characterized in that the emorization paper has a graining ranging from 40 to 1,000, preferably 100 to 500. 19

13. Method according to one of the claims 9 to 12, characterized in that the emorization takes place before the coating of the substrate with the adhesive.

14. Method according to one of the claims 9 to 13, characterized in that the emorization takes place during a finishing method before the coating.

15. Method according to one of the claims 9 to 12, characterized in that the emorization takes place after the coating of the substrate with the adhesive.

16. Method according to one of the claims 11 to 15, characterized in that the several emorization rollers are driven independent of each other and rotate independent of each other with or counter the movement of the elastic insert.

17. Method according to one of the claims 1 to 16, characterized in that the at least one emorization roller rotates at a rate of 8 to 20 m/min.

18. Use of an elastic insert according to one of the claims 1 to 8 for reinforcement of pieces of clothing, in particular the front parts of clothing.