ES2334825T3 - WASHABLE WOOL ELASTIC FABRICS WITH DIMENSIONAL STABILITY AND MANUFACTURING METHOD. - Google Patents

Abstract

The present disclosure is directed to washable wool stretch or elastic textile articles which are dimensionally stable. Preferably, the articles are characterized in that they have not been subjected to temperatures greater than 1600 C. The disclosure is also directed to a method to make dimensionally stable wool stretch articles characterized by the absence of a traditional heat-setting step.

Description

Elastic woven wool fabrics with dimensional stability and manufacturing method.

The present invention relates to tissues Wool elastics, machine washable, with good stability dimensional. The tissues also have improved properties of heat set. In one aspect, the invention relates to tissues. elastics comprising wool fibers together with elastic fibers, where the elastic fibers comprise resilient elastic fibers heat, crosslinked and where such fabric does not require thermofixing, but the finished fabric can provide very good stability dimensional after many washes.

Fabrics made at least in part from fibers Wool are well known in the art. It is also known that these tissues may shrink or otherwise become deformed during wet tissue treatment or as a result of use and consumer care The wool consists of an outer layer at scales that overlap around an inner core that consists of many fine, long needle-shaped cells, consisting of Much keratin. The outer layer generally has a single thickness scale, except in the portion that overlaps on the In case you finish one scale and start another. All scales they generally point out along the fiber, toward the tip. It is believed that this structure leads to shrinkage during normal wet washing, since the fiber profile favors the movement in the direction of the tip of the fiber root. This behavior can be compared with a ratchet mechanism. in which the relative movement is unidirectional. The fibers are compact more and more until they are fully compacted and It forms a "felted" wool. It has been indicated that the felted increases in the presence of water, particularly along with agitation mechanics.

To combat shrinkage, they have been used chemical treatments to take off the external scales of the wool. Once the scales are removed, the phenomenon is then eliminated of "felting" and shrinkage is minimized. The various Chemical treatments used today are generally done on the wool finish and include various treatments with Chlorine, potassium permanganate treatments along with hypochlorite treatments (see Britain's patent 569,730), sodium sulfate (sometimes referred to as the Procedure of the International Wool Secretariat), oxidase treatments or peroxidase (see U.S. Patent 5,980,579) and treatments with permonosulfuric acid. It has also been suggested that Permonosulfuric acid treatments can be on a garment Finished made of wool fabric to control stability dimensional. These treatments have produced fabrics and garments that can be labeled "Machine washable" or "Easy Care Total ", which indicates that the garments are suitable for washing in domestic machines using the approved Woolmark cycle (washing of wool or soft cycle at 40 ° C) with a bleach and detergent without enzymes

Garments are said to be Machine Washable when they satisfy the following industrial pattern:

Stability Dimension of the garment / fabric:

stability dimensional following washing less than ± 3 percent (the Washing can be done in accordance with the modified ISW Tm 31: 5 ISO 6330 5A wash cycles, wet measurement)

stability dimensional after steam ironing in accordance with ISO 3005 less than ± 3 percent

Although there are washable woolen garments to machine, currently do not contain elastic fiber to help provide elasticity to the tissue. The stretchable garments have gone gaining popularity in the fashion industry. Fiber has been used spandex with wool to make a stretchable wool fabric but not considers said fabric washable because it does not have a adequate dimensional stability. In addition, it is believed that chemical treatments such as chlorine and acid treatments permonosulfuric described above are too hard to the spandex, which would result in unacceptable levels of breakage of spandex fiber, thereby limiting the flexibility of the process why chemical treatments should be carried out In the absence of spandex fiber.

Additionally, dimensional instability is manifests even before the tissue is exposed to exposure to water as it is indicated that wool / spandex fabrics have a very poor consistency in tissue width, as indicates varying the widths between different tissue rolls or by the variation of width in the same fabric roller.

To overcome these issues, producers of current fabrics that wish to use a wool / spandex fabric typically apply one or more additional processes of high temperature heat setting to "fix" the width of the tissue and adjust the width of the fabric within the range wanted.

Thermosetting is a common way to reduce or eliminate dimensional instability. The heat setting process  typically involves passing tissue through an area of heating for a while and at a temperature that restores the morphological memory of synthetic fiber to the dimensions of fabric at the time the heat setting process was applied. The time and temperature needed for heat treatment depend on factors such as tissue structure, weight of the tissue, other fibers present in the tissue, the type of fiber Synthetic and previous thermal history of synthetic fiber. He issue of dimensional instability is especially pronounced for stretch fabrics, in particular stretch fabrics of point.

For elastic fabrics, such as those incorporate spandex, the typical thermofixation conditions are from 180 ° C to 210 ° C for 15 to 90 seconds. These conditions relatively hard can adversely affect the toughness of the accompanying fibers and lead to the alteration of the color of the tissue. In addition, the thermosetting stage is typically a stage. additional that is added at the expense of the production process of the tissue. It is indicated that the finished wool / spandex fabrics have a very poor consistency in tissue width, such as It is indicated by varying the widths between different fabric rollers or by variation of the width in the same fabric roller. He thermosetting process will cause the level of elasticity of the Finished fabric is inconstant.

According to this, it would be desirable to have a dimensionally stable wool fabric with elastic fibers that do not requires a special heat setting stage, so that you can carry out heat setting simultaneously with other stages in The process of tissue production.

The present invention relates in accordance with this to wool fabrics that incorporate stretch fibers or elastic, fabrics that retain their dimensional stability, preferably without the need for heat setting steps Traditional The present description also refers to a Production method of stretch wool fabrics with good dimensional stability, in which the method is characterized by a chemical treatment to remove wool scales and characterized also for the absence of any stage in the process of production that is carried out at a temperature of 160ºC or above. Stretchable fabrics can also include other fibers including cellulosics, more preferably synthetic ones including polyolefin such as polyethylene and / or polypropylene, polyester, polyamide and segmented polyurethane fibers. The tissues stretchable finishes preferably have stability dimensional less than ± 5 percent, more preferably less than ± 3 percent, even more preferably within ± 2.0 percent and most preferably within ± 1.5 percent. The dimensional stability values indicated in this invention they refer to the difference between length and dimensions in the sense of the width of the finished fabric after washing versus before washing, more drum drying, as defined by AATCC135-1987; preferably by the method of Drying: A - Drum drying. Negative values indicate that final washed dimensions are shorter than the initial ones, which translates into shrinkage.

The present invention also relates to tissues that can be characterized by elasticity consistent to 9 percent - 30 percent according to the IWS TM test method 179. The present invention can also be characterized in that the Finished fabric color is free from yellowing perceptible.

International Patent WO 03/078705 describes a thread comprising an elastic fiber and an inelastic fiber. The International Patent WO 03/078723 describes an elastic article that It comprises a crosslinked elastic fiber and an inelastic fiber.

Stretchable wool fabrics, washable to machine, of the present invention comprise at least fibers of wool and elastic fibers. The wool fibers of the present invention they can be any type of wool fiber used in the industry the clothes. Typically, the wool used will be the fleece fiber of sheep or lambs but also includes goats hair fiber Angora or Kashmir, camels, alpacas, llamas, vicunas and rabbits Angora, for example. Wool can be present in any amount, but most preferred is 20-99 percent in weigh. Depending on the desired application, it may be desirable have at least 35 percent, 50 percent, 60 percent or even 70 percent wool and similarly, the application can impose that you have less than 98 percent, 97 percent, 96 percent percent, 95 percent, 80 percent, 75 percent or 70 percent woolen.

Whatever the source, the wool fibers in their natural state they can be characterized by having scales that they tend to decrease and intersect with each other joining that mode the fibers in a process called felting. In accordance with this, wool fibers are treated for use in the present invention to remove at least a portion of the scales. This Treatment procedure is generally known in the art and any of these procedures may be used herein invention. Typical processes include chlorine treatment and treatment with permonosulfuric acid. The examples of potentials Chemical treatments for use in the present invention include those described in US Pat. 5,980,579, the patent International WO 2005/005710, European Patent EP 0 687 764, the U.S. Patent 5,571,286, U.S. Pat. 5,755,827 and the WO 9502085 international patent.

The scale removal treatment can be do at any stage in the process to make a garment. By example, in many cases the most advantageous will be to eliminate the scales as a first stage so that it doesn't take place felted during any of the subsequent production processes, but in other situations it may be beneficial to wait until it have prepared the final garment and then treat the entire garment to remove at least a portion of the fiber scales from wool. You can also do the treatment in intermediate stages such as after forming the wick, the finish, the strand, the thread (including elastic threads if combined with elastic fiber) or After making the fabric. Typically the treatment is done in the finished or in the finished garment.

The machine washable fabrics and garments of the present invention are stretchable or elastic, which means for the purposes of this invention, which contain an elastic fiber.

For the purposes of the present invention, a elastic fiber is one that will recover at least approximately 50 percent, more preferably at least about 60 percent, even more preferably 70 percent of its stretched length after the first pull and after the fourth to 100 percent elongation (double the length). A way appropriate to perform this test, is based on the one found in the International Agency for the Standardization of Synthetic Fibers, SPARK 1,998, chapter 7, option A. Under such a test, the fiber is place between pincers separated 10.16 cm (4 inches), the tongs later at a speed of approximately 50.8 cm per minute (20 inches per minute) at a distance of 20.32 cm (eight inches) and then allowed to recover immediately. Be prefers the elastic textile articles of the present invention have a high percentage of elastic recovery (it is that is, a weak permanent percentage deformation) after application of a deforming force. Ideally, the materials Elastic are characterized by a combination of three properties important, that is, (i) a weak tension or load on the deformation; (ii) a low percentage of tension or relaxation of load and (iii) a low percentage of permanent deformation. In in other words, there should be (i) a low voltage requirement or load to stretch the material, (ii) zero or low relaxation of the tension or discharge once the material is stretched and (iii) full or high recovery to the original dimensions after stretching, deformation or elongation interrupted.

Elastic fibers include certain fibers made of polyolefins such as polyethylene or polypropylene and segmented polyurethane. Elastic fiber for use herein invention is preferably durable enough to survive the scale removal treatment so that such Treatment can be done in the presence of elastic fiber. Be therefore prefers that the elastic fiber be a fiber of crosslinked polyolefin, more preferably a fiber of crosslinked polyethylene, of which they are particularly preferred homogeneously branched, crosslinked ethylene polymers. This material is described in US Pat. 6,437,014 and is known generically as lastol. Such fibers are available in The Dow Chemical Company with the trade name of DOW XLA fibers. Be prefers elastic fibers to comprise 2 to 20 percent by weight of the article. Depending on the desired application, you can prefer that the article comprises at least 3, 4, 5, 6, 7, 8, 9 or even 10 percent elastic fiber and similarly, the Desired application may impose less than 20, 15, 10, 9, 8, 7, 6 or 5 percent elastic fiber. It may be desirable that knitted items contain relatively more elastic fiber than woven items.

It is also possible, although not necessarily preferred, that more than one type of elastic fiber can be used in the articles of the present invention. It is preferred that the fibers Elastic do not include fiber made of segmented polyurethane, without However, since this material is likely to degrade under relatively hard chemical treatments used to scale and also favor dimensional instability in the absence of thermosetting at temperatures greater than 160 ° C.

The elastic fibers for use in the present invention may be of any thickness, although 20-140 denier is most preferred, in particular when the fiber is of the homogeneously branched, crosslinked, preferred ethylenic polymers. Forty denier and 70 denier lastol fiber are especially preferred due to commercial availability. In addition to a monofilament fiber, the elastic fiber can also be a conjugate fiber, for example, a bicomponent fiber with sheath / core. The bare elastic fiber can be used or it can be incorporated first into a multifilament, for example covered yarn or cut fibers, for example, core or corespun yarn, as is generally known in the art. In a preferred embodiment the elastic fiber is siro-spun with the wool to form an elastic wool yarn.

The textile articles of the present invention they may also comprise more natural or synthetic fibers, not elastic. Non-elastic synthetic fibers include the Produced from materials such as: polyester, nylon, polyethylene, polypropylene and mixtures thereof. Natural fibers They include fibers made of cellulosic materials such as: Cotton, linen, ramie, rayon, viscose and hemp. Can also be use natural fibers of other materials in textile articles of the present invention, including fibers such as silk or mohair.

Stretchable wool fabrics, washable, from the The present invention can be made by any conventional means.  Thus, the articles of the present invention include fabrics that are have woven (in case the fiber or elastic thread can be in the warp sense, the plot sense or both) or made of knitting including warp knitting, (for example, work of Milanesa, Raschel and Tricot point), plot point work (for example, circular knitting and smooth knitting) and technologies for making knitwear such as articles Withouth stitches. It is also not desired that the type of structure of Weaving is a limiting factor of the present invention. The Known structure types include: jersey knitting simple, plain, simple jersey knitting that contains jareta and skipped stitches (such as Pique Lapique, Cross-mis 1x1, Lacoste & Plain), fabrics of double jersey knit (such as Plain Rib and Plain Interlock), fabrics Knitted double jersey containing jareta and skipped stitches (such as Milano Rib, Cardigan, Single Pique & Punto di Rome).

It is known that wool fabrics and in particular knitted wool fabrics, experience a lack of dimensional stability throughout domestic washes, for example, excessive stretching or shrinking. Traditional methods of producing knitted fabrics include, therefore, a heat setting stage, in particular when the fabric includes fibers incorporating synthetic polymers. The thermosetting stage is performed after knitting and can be performed before or after dyeing. The thermoforming process generally involves applying a deforming force to maintain the fabric in its desired dimensions (typically with the use of stretcher frames) and subjecting it to high temperatures, in particular temperatures above any temperature that the fiber or article probably reaches in subsequent treatments (for example, dyeing) or use (for example, washing, drying and / or ironing). Although not intended to be limited by theory, it is believed that the thermosetting process generally works as follows: The thermosetting temperatures are such that at least some of the fiber crystallites will melt. The tissue is then removed from the heat and the molten parts are allowed to recrystallize and then the deforming force can be removed. Recrystallization causes the tissue to have a "memory" of the dimensions in which the tissue was maintained during the heat setting treatment, even after the force has been removed
warping

It has been discovered that by selecting certain synthetic, elastic fibers, for use in knitted fabrics, are you can skip the thermosetting stage, although still producing a fabric with acceptable dimensional stability. An aspect of the The present invention therefore relates to a method for produce a knitted wool, machine washable, characterized in that the entire process takes place at a temperature below about 160 ° C. Depending on content of other fibers that constitute the tissue, even can use lower temperatures without sacrificing stability dimensional. Thus, the entire process can take place at a temperature below 150ºC, 140ºC, 125ºC, 100ºC or even 80 ° C

In certain embodiments of this invention, the procedure can be further characterized by an absence of stretching. Thus, threads or fibers can be knitted into fabric that contain at least some elastic material and can be submitted directly the fabric to the desired finishing treatments without the need to place the fabric in a stretch frame and expose it at the high temperatures normally associated with the thermosetting

It is preferred that finishing treatments include at least one stage where the temperature is higher than 80 ° C In this way, the tissue will be "fixed" in a similar way. to the typical thermosetting process, but at a lower temperature and without the need for a special device to guarantee a force warping Typical finishing stages are performed at temperatures 80ºC or higher, which are sufficient for these purposes and even such fabrics will not normally be exposed to such high temperatures during normal use and care.

The present invention also relates to woolen textile articles, machine washable, elastic and dimensional stability. For the purposes of the present invention, "textile articles" include finished fabric as well as products produced from fabric, including sheets and other white clothes and clothing. It is preferred that articles of the present invention, particularly jersey knits simple, smooth, of the present invention, immediately recover the dimensions that are less than 20 percent of its dimension original after having stretched up to (1) 100 percent in the sense of width and / or (2) 45 percent longitudinally (all at an extension speed of 500 mm / min for a sample 50 mm wide and 100 mm calibrated length). Plus preferably, the item will return within 15 percent of the original dimensions and more preferably within 10 per hundred. It should be understood that the amount of stretching and recovery will be a function of tissue weight and structure of the tissue. It is also considered that the articles of this invention will have elasticity in more than one direction and by Of course this will be preferred for many applications. It is not necessary that the articles have the same amount of elasticity in each address to be within the scope of this invention.

The textile articles of the present invention They are dimensionally stable. For the purposes of this invention "dimensionally stable" means that stretched tissues change less than 5 percent in any direction (stretched or shrinkage), more preferably less than 3 percent in any address and even more preferably less than 2 per percent in any direction and most preferably within ± 1.5 percent. Shrinkage is generally perceived as the typical form of dimensional instability and the tissues of the The present invention will have greater dimensional stability (this is, less negative) than -5 percent in the width direction and / or the longitudinal direction, preferably greater than -4 per percent, more preferably greater than -3 percent and most preferably greater than -2 percent (representing 0 per hundred not shrink or stretched). Stability values dimensional are calculated by the difference between the dimensions to the length and width of the finished fabric after washing against before washing. To determine dimensional stability, measure the length and width of the finished article, then subject the article to washing (such as the method described in the AATCC135-1987 drying method: A - drying in drum. After washing and ironing, the length and length are measured again. width and the percentage is calculated according to the formula: dimensional stability = (new dimension - dimension original) / original dimension. How you will easily understand the professional, negative values indicate that the dimensions final washes are smaller than the initial ones, which translates into shrinkage.

It should be understood that, depending on the fibers present in the tissue, some thermosetting may be beneficial,  even if such heat setting is not required as a result of using the preferred elastic fibers of the present invention. By example, if polyester is present it may be advantageous to use temperatures around 160 ° C to provide stability dimensional to polyester content only. Even fabrics that contain cotton are frequently exposed to temperatures so high as 140 ° C in order to dry after the treatments of wet finish Thus, it may be desirable to have a stage of temperature finish as high as 140 ° C for fabrics that contain cotton of the present invention.

After forming the raw tissue, it can be used any finishing procedure known in the art. This includes procedures such as washing, mercerizing, dyeing and dried It is preferred that at least one of the finishing procedures at a temperature that is higher than anyone to whom the final consumer will likely expose the garment, for example 80 ° C or higher.

Examples Example 1 Polyester blend with wool and fiber 40D DOW XLA?

Wool fiber is chemically treated with a Chlorine treatment on wool finish to remove scales woolen. Then this treated wool fiber is mixed with polyester to produce a thread that is approximately 65 per percent by weight polyester and 35 percent by weight wool. Later dye the fiber mixed. Then the dyed fiber is combined with 40 denier DOW XLA? fiber (available from the Dow Chemical Company) at a stretch of 4.3 through siro-spinning to produce an elastic thread. The thread elastic is used in the weft direction to make a fabric with a warp thread (the warp thread is dyed fiber of polyester / wool prepared as before, without siro-spun with DOW XLA? fiber computation (Nm) 52 twisted threads to two ends and one count of weft thread (Nm) 52 twisted two-wire strands with 24 tips / cm and 22.5 strands of weft / cm The resulting tissue contains approximately 33 per percent by weight wool, 63 percent polyester and 4 percent of Dow XLA fiber. The resulting tissue has a weight (when determined by ASTM D3776-1996 (2.002)) of 240.7 gm / m2 (240.7 GSM). The fabric is finished according to Classic procedures and measured. The finished fabric has a 16 percent stretch level when determined from according to IWS TM 179. The tissue is subjected to the IWS test method 31: 5 wash cycles ISO 6330 5A, wet measurement. Later re-measure the tissue.

The fabric shows shrinkage in the washing of frame (IWS TM 31 test method) less than 1.9 after 5 washed As the industrial pattern for "washable" garments machine "is less than 3 percent, this fabric satisfies Easily industrial pattern.

Examples 2-5 wool

Super 100 Superwash wool blend with 40D DOW fiber XLA?

It is chemically treated Super 100 wool fiber Superwash that has been treated with a chlorine treatment in the Wool finish to remove wool scales. Then it combines wool treated with 40 denier DOW XLA ™ fiber at a stretch 4.3 through siro-spinning to produce a thread elastic. The thread is used in the weft direction (the warp it was 100 percent wool) to make fabrics with a count (Nm) of weft thread 80 twisted to two ends and a count of thread weft (Nm) 76 of twisted wires to two ends. The resulting tissue it's about 96 percent wool and about 4 percent DOW XLA ™ elastic fiber, which may vary depending on the particular structure of the tissue.

A series of different structures are prepared of tissue as explained in Table 1 and the tissues are stained and They just agree with classic procedures. Each had one width of approximately 150 cm. Stability is tested dimensional of these tissues after 5 wash cycles of According to ISO 6330 5A washing method, wet measurement, as in Example 1 (that is, IWS TM31). It is also tested in dimensional stability fabrics after steam ironing according to the ISO 3005 test method. The stretching and extension not recoverable in the direction of the plot according to IWS TM 179. These examples are summarized in the Table 1 and as you can see in the table, all the examples meet the industrial standard for "machine washable".

TABLE 1

one

Claims (19)

1. An article of washable wool, comprising wool that has been treated to remove at least a portion of its scales and also comprising elastic fibers comprising a crosslinked polyolefin polymer, wherein said article it has dimensional stability after washing and / or ironing with steam within ± 3 percent. 2. The article of claim 1, wherein the elastic fibers comprise an ethylene polymer homogeneously branched, crosslinked. 3. The article of claim 1, wherein the article has not been subjected to temperatures greater than 160 ° C. 4. The wool article of claim 1, which has dimensional stability after washing and / or steam ironing of ± 1.5 percent. 5. The item of washable wool from the claim 1, wherein the article comprises 2-20 percent by weight elastic fibers. 6. The washable wool item of the claim 1, wherein the article comprises at least 65 by percent of wool 7. The item of washable wool from the claim 1, further comprising natural fibers or synthetic, non-elastic, additional. 8. The article of claim 2, wherein fibers made of homogeneously branched ethylene polymer, crosslinked, comprise 2 percent to 10 percent by weight of the Article. 9. The article of claim 1, wherein The article comprises fibers made of polypropylene. 10. The article of claim 1, in the that the item is in the form of a garment. 11. The article of claim 1, in the that the item is in the form of white clothes. 12. The article of claim 1, in the The item is in the form of finished fabric. 13. The article of claim 1, wherein the wool item comprises 70 to 96 percent by weight of wool. 14. A method to produce an article Stretchable wool, washable, dimensionally stable, comprising elastic fibers made of a crosslinked polyolefin polymer and wool fibers that have been treated to remove at least one portion of its scales, in which no stage is carried out in the process of finishing the article at a temperature that exceeds of 160 ° C. 15. The article of claim 1, in the that the treatment to remove at least a portion of the scales it is a chlorine treatment or an acid treatment permonosulfuric. 16. The article of claim 15, in the that the treatment is done to the article. 17. The method of claim 14, further characterized in that the method does not include the use of a stretch frame. 18. The method of claim 14, further characterized in that the finishing of the article includes a thermosetting step. 19. The method of claim 14, wherein the article additionally comprises polyester fibers or nylon.