JP6714077B2 - Polyamide fibers having improved comfort management, methods thereof, and articles made therefrom - Google Patents

Description

The present invention relates to polyamide fibers having improved comfort management properties. The invention also discloses methods for obtaining such fibers and articles made therefrom. Polyamide fibers are manufactured from hygroscopic polyamides of multi-lobed cross-section profile. The hygroscopic polyamide fiber is preferably polyamide 5. Manufactured from X, where X is preferably an integer from 4 to 16. Most preferred is polyamide 5.6, which is a bio-sourced polyamide obtained from pentamethylene diamine and is derived from a renewable source of sugar-based ingredients. As such, the present invention discloses polyamide fibers and articles made therefrom for sportswear and leisurewear applications that have improved water absorption, wicking, and drying properties, where sweat is separated from the skin. It is carried and dried quickly, thereby reducing the wet feeling and coldness during activity. The present invention provides freshness and comfort by maintaining a comfortable skin temperature and in-cloth climate.

There is an increasing demand for comfort in sportswear and leisure wear clothing. According to the World Sports Activewear, “comfort is the most important thing in clothing,” and it is the number one consumer expectation. Comfort not only affects the wearer's satisfaction, but also their performance and ability. For example, if a hard-moving person wears a poorly breathable garment system, heart rate and rectal temperature will increase much more rapidly than when wearing breathable sportswear.

Polyamide fibers are the most suitable synthetic fibers available on the market for improving comfort. Polyamide is very soft, smooth and comfortable on the skin. In addition to a very balanced moisture behavior, it offers a very comfortable sensation due to its high flexibility, light weight and abrasion resistance. Polyamides also have high durability, good physical and chemical properties, easy care, and fast drying.

Polyamide, also known as nylon, is a linear condensation polymer consisting of repeating main bonds of amide groups. The amide group (-CO-NH-)- provides a hydrogen bond between polyamide intermolecular chains. Polyamide fibers are usually produced by melt spinning extrusion and are available in staple fiber, tow, monofilament, multifilament, raw or textured form.

As such, polyamides are promising candidates for sportswear, underwear, leisure wear, and other applications on bare skin. Fabrics on bare skin are typically soft, skin-friendly fabrics made of hydrophilic and/or porous fibers and are designed to wick sweat away from the body to maintain a comfortable skin climate in clothes. Sweating is the mechanism required to cool the body in response to the production of high levels of body heat. When sweating, the climate inside the clothing of the skin suddenly becomes humid. For efficient cooling, evaporated sweat needs to be carried as water vapor by convection through a layer of air adjacent the clothing and skin and/or through the openings in the clothing.

Fabrics on bare skin control climate temperature in clothing and skin humidity. In hypometabolic activities, the fabric must have reduced air movement, as the in-cloth climate is maintained by the air that remains. Higher metabolic activities require the transfer of heat and moisture from the dough to cool the skin. The control of water is then carried out by absorption, transport or ventilation.

In moderate activity, where only a limited amount of sweating occurs, absorption lowers skin humidity and maintains relative comfort, while in more metabolic activity and intense sweating, water remains in the clothing system. There is a possibility that the heat insulation efficiency decreases due to wet clothes, which may adversely affect the heat balance at a later stage, which reduces comfort and makes you feel chills after stopping activity. Give rise to. Therefore, in conditions of more perspiration, the transport principle should be applied, in which case sweat is carried away from the skin by wicking and capillarity, which keeps the skin dry.

Synthetic fibers are durable and easy to care for, but most are hydrophobic. The use of hydrophobic textiles on bare skin causes a rapid increase in humidity due to perspiration, so hydrophobic fabrics carry water away quickly due to the space between the fibers and the threads due to the capillary action. Need to be designed. On the other hand, hydrophilic and/or hygroscopic fibers absorb and transport water by the fibers themselves and by capillarity, thus promoting evaporation.

Highly hygroscopic fibers also give rise to physiologically problematic prolonged drying times. If the drying time is too long, the sweat-wet shirt loses its heat insulating properties and thus the chills after exercise cannot be avoided. This mechanism is usually found among these due to the very high hydrophilic properties of natural and regenerated fibers. In addition, wet skin can cause skin irritation and even skin diseases caused by moisture.

Wool, for example, has a high absorption capacity and can accommodate small amounts of water without losing its insulating properties. Wool can be used as a fabric on bare skin and can keep the skin relatively dry. However, when the dough becomes saturated, the controllability of water decreases. Cotton has very good properties for the garment to be worn under normal wearing conditions, where it perspires only a limited amount. In this situation, cotton can reduce sweat irritation to a smaller extent, thus keeping the in-cloth climate drier and more comfortable. However, in the field of sports textiles, where more liquid sweat is produced over a longer period of time, cotton is only recommended on the outside of the laminating material and in combination with the synthetic side on the skin side. .. When cotton is used alone or as the primary fiber component, the fiber product becomes damp with water and rapidly wets and sticks to the body.

Water absorbed by clothes gradually loses its heat insulating property. When activity ceases and sweating subsides, the drying of layers of wet clothing can draw more heat from the body than is generated by metabolic rates, resulting in endangered heat balance and hypothermia. The effect of causing chills after exercise that may cause Post-exercise chills can be avoided by short drying times. In fact, a short dry time is one of the main prerequisites for good comfort with sportswear.

In summary, textiles are required to have reasonable hydrophilicity, high wicking rates, and fast drying rates to be effective in maintaining a pleasant in-cloth climate and comfort. If the hydrophilicity is too high, as in the case of natural fibers, water can be absorbed and retained inside the fibers for longer periods of time, which can slow the drying rate. Poor wicking can result in saturated areas and also reduced transport and drying rates. Therefore, it is necessary to achieve an optimum balance between hydrophilicity, wicking property, and quick-drying property.

There has been a significant amount of research activity to improve the moisture management of polyamide fiber products. Several approaches have been used, such as adding a hydrophilic material in the fiber matrix or on the fiber surface such as polyvinylpyrrolidone (PVP) and ethoxylated polyamide, or blending the polyamide with another hydrophilic polymer by two-component melt extrusion. Has been adopted. An example of a sheath-core polyamide multifilament is disclosed in JP 2012-211406 A, in which a polyalkylene oxide modified product is used as a core material. This approach requires a two component device. Also, the drying rate and wicking rate cannot be obtained.

In another approach, a cooling agent is added to the polyamide fiber matrix to improve cooling and moisture management properties. This method is disclosed in Chinese patent applications, Chinese Patent No. 104178839 and Chinese Patent No. 1030888459. Disadvantages of this approach include lack of fast drying, water absorption, and wicking rate. This cooling mechanism may also cause unpleasant sensations such as hypothermia due to excessive cooling during sweating due to activity.

A Chinese patent application, Chinese Patent No. 1038282550, also proposes a cooled polyamide fiber using a cooling agent such as inorganic metal oxide particles, but PVP is added to the fiber for the purpose of improving water absorption. It The disadvantage of using PVP is that the presence of pyrrolidone as a by-product tends to cause yellowing of the fibers, thereby affecting desirable mechanical and chemical properties for textile applications. is there. Moreover, rapid wicking and dryness effects have not been demonstrated and can cause discomfort during excessive sweating and sports activities.

A few patents attempt to provide polyamide fibers that manage moisture only by changing the cross section of the fiber. Filaments with cross-sections other than circular are generally proposed for aesthetic effects, moisture management, and light weight. Examples of non-circular contours include "dogbone", "trefoil", "zigzag", "king", "flat", and "hollow". This approach aims to increase the capillarity effect by introducing grooves and microchannels in the longitudinal direction of the filament to create spaces within and between the fibers. For example, the trefoil contour (also called Y) is well known and widely used for imparting luster and vividness to articles, but it does not provide deep minute flow paths, and thus capillary phenomenon, Does not increase softness and surface area. Japanese Patent No. 5206640 discloses an improved cross-section polyamide having radial lobes. However, water absorption, wicking properties, and drying rate have not been evaluated or improved.

U.S. Patent Publication No. 2015013047 disclosed chilled polyamide yarns that use inorganic cooling additives, improved cross-sections, and low crimp modules. The disclosed cross section is a flat cross section. The drawback of this cross-section is that the flattened fiber contours cover the skin better, reduce heat insulation, reduce air entrapment, and increase the number of points of contact with the skin, which can reduce the feeling of comfort of the skin. .. It does not lend itself to capillarity, nor does it increase wicking and drying rates, making it less suitable for more sweating activity. Furthermore, the flat cross sections evaluated in the experiments of the present invention showed inferior processing behavior. This suggests that it may be more difficult to process flat cross sections by melt spinning.

Finally, EP 2 547 721 discloses hygroscopic polyamide 5.6 fibers. However, there are no additional benefits of high wicking and drying rates as provided by the present invention. Therefore, EP 2 547 721 does not provide a solution for comfort management of sportswear textiles where wicking properties and faster drying rates are desired.

Fibers that simultaneously provide hydrophilic properties, cooling effects, and wicking properties still do not exist on the market.

In view of the above, there is a need for synthetic fibers that have substantially improved comfort management properties with the additional benefits of fast drying and wicking properties that mimic the softness and comfort of natural fibers. There is.

There is also a need to provide a solution for having a comfortable polyamide fiber product including:
-Optimal hygroscopicity for absorbing perspiration without the feeling of being wet and maintaining ideal thermal insulation in the clothing climate.
-Enhanced wicking speed to carry sweat away from the skin efficiently.
-A fast drying rate to keep the skin dry and avoid the unpleasant chilly feeling after exercise.
-Sensory skin comfort for a pleasing texture with textured multifilament yarns with multiple very fine filaments.

Accordingly, it is an object of the present invention to provide a polyamide fiber having excellent comfort management properties, a method thereof, and an article made therefrom, thereby improving the in-cloth climate of the skin during sports and heavy sweating activities. And to create a comfortable sensation.

The present invention is a solution for obtaining a polyamide fiber that gives a very comfortable and refreshing feel in order to give the wearer a comfortable sensation.

Therefore, the present invention relates to polyamide 5. Having improved comfort management, including hygroscopic polyamides, which are bio-based aliphatic polyamides selected from the group consisting of X (where X is an integer from 4 to 16) and mixtures thereof. Polyamide fiber having a multilobe cross section characterized by having at least two coalesced centers and at least five equally sized elliptical lobes, each coalesced center being adjacent and equal. Provided are polyamide fibers connecting at least three equally sized elliptical lobes according to angular symmetry between sized elliptical lobes.

Surprisingly, it has been found that such polyamides exhibit significantly greater hygroscopicity, water drying rate, water diffusion rate, and water absorption compared to non-hygroscopic polyamides having a circular cross section. It has been found that better water management and better comfort are obtained by increasing water absorption, wicking and drying rates.

The present invention is a method for obtaining said polyamide fiber with improved comfort management, wherein the polyamide fiber comprises a hygroscopic polyamide, for example by using a new multilobe cross-section spinneret. A method, obtained by melt-spinning extrusion of a product, is also intended.

The present invention also proposes a polyamide article comprising polyamide fibers with improved comfort management, as defined above and in the following paragraphs, and a method for obtaining such a polyamide article, wherein: The inventive polyamide fibers are converted by texturing, drawing, warping, knitting, weaving, non-woven, sewing, or combinations thereof.

Another object of the invention is also to improve the comfort management of said polyamide fibers with improved comfort management as defined above and in the following paragraphs, of polyamide articles produced therefrom, in particular textile articles. Is the use of.

A schematic example of a multi-lobe section. A schematic example of a special spinneret orifice. Other cross section contours.

Definitions The expression "polyamide fibers" in the sense of the present invention is the usual term including the following spun articles: fibers, monofilaments, multifilaments and yarns. The "polyamide article" of the present invention is a converted or treated polyamide fiber, a staple fiber made from the polyamide fiber, any flock or any textile composition, especially textiles and/or garments. In the following description, the terms "fiber", "thread" and "filament" can be used independently without changing the meaning of the invention.

Polyamide Fibers With Improved Comfort Management The present invention relates to polyamide 5. Having improved comfort management, including hygroscopic polyamides, which are bio-based aliphatic polyamides selected from the group consisting of X (where X is an integer from 4 to 16) and mixtures thereof. Polyamide fiber having a multilobe cross section characterized by having at least two coalesced centers and at least five equally sized elliptical lobes, each coalesced center being adjacent and equal. Provided are polyamide fibers connecting at least three equally sized elliptical lobes according to angular symmetry between sized elliptical lobes.

Hygroscopic Polyamide Hygroscopic polyamide is polyamide 5. An aliphatic polyamide comprising X (where X is an integer of 4 to 16) or a mixture thereof.

Polyamide 5. X is produced from pentamethylenediamine as a raw material and an aliphatic dicarboxylic acid. The list of potential dicarboxylic acids is: butanedioic acid (succinic acid), pentanedioic acid (glutaric acid), hexanedioic acid (adipic acid), heptanedioic acid (pimelic acid), octanedioic acid (suberine). Acid), nonanedioic acid (azelaic acid), decanedioic acid (sebacic acid), undecanedioic acid, dodecanedioic acid, brassylic acid, tetradecanedioic acid, pentadecanedioic acid, hexadecanedioic acid. All these diacids are commercially available.

Polyamide 5. X has the advantage that it can be produced from biomass according to ASTM 6866. Pentamethylenediamine can also be synthesized from biological sources according to ASTM 6866 and the resulting polyamide can be made from 40% to 100% biological sources.

The amino end group (ATG) content of polyamides derived from these organisms is preferably 25 to 60 equivalents/ton, and the carboxyl end group (CTG) is preferably 45 to 90 equivalents/ton. These amino/carboxy end group contents are measured according to the method described in the experimental section below.

The hygroscopic polyamide is preferably a polyamide 5.4, a polyamide 5.6, a polyamide 5.8, a polyamide 5.10, a polyamide 5.12, a polyamide 5.14, a polyamide 5.16, and mixtures thereof such that X is Polyamide which is an even number from 4 to 16. It is X. More preferably, X is 6 or 10, advantageously 6 such as polyamide 5.6 (nylon 5.6, also known as poly(pentamethylene adipamide)), which has pentamethylene diamine as raw material and It is produced by a polycondensation reaction with adipic acid.

A preferred polyamide 5.6 may have a viscosity index (IVN) in the range 100-200 ml/g, preferably about 120-170. This IVN is measured according to the ISO 307 standard, which is explained in the experimental section below.

A particularly preferred polyamide 5.6 of the present invention has an IVN (viscosity index) of 138-142 and an ATG (amine end group) of 38-42.

The hygroscopic effect of polyamide 5.6 measured according to the method described in the experimental section below is at least 4%. The hygroscopic character is due to the odd/even configuration of the diamine (5 carbons) and the diacid (6 carbons). This imbalances the intermolecular bonds and reduces intramolecular hydrogen bonding, resulting in more accessible sites within the molecule that are more compatible with water.

The polyamide fibers of the invention advantageously comprise more than 75% by weight hygroscopic polyamide, preferably more than 85% by weight, more preferably more than 95% by weight, based on the total weight of the fibers.

In practice, the polyamide fibers of the present invention are stable polymers such as PA6.6, PA6.10, and other polymers and/or stabilizers such as plasticizers, antioxidants, stabilizers, heat or light stabilizers. Agents, colorants, pigments, nucleating agents such as talc, matting agents such as titanium dioxide and zinc sulfide, processing aids, biocides, viscosity modifiers, cooling agents, catalysts, far infrared emitting minerals, antistatic Additives such as agents, functional additives, optical brighteners, nanocapsules, antibacterial agents, antimitic agents, antifungal agents, or other conventional additives may be included.

Usually, the amount of additive in the fiber corresponds to a maximum of 25% by weight, more preferably a maximum of 10%.

In another embodiment of the invention, a cooling or temperature regulating agent is used. As the cooling agent, any far infrared ceramic powder, an inorganic filler such as an inorganic metal oxide (for example, TiO2, ZrO2, MgO, SnO2, ZnO, BaO), a jade powder, a zirconia powder, a silica powder, mica, boron nitride, Calcium carbonate, barium carbonate, magnesium carbonate, aluminum silicate, alumina, zeolite, and talc may be included. Temperature control agents also include phase change materials such as paraffin, or endothermic substances such as sugar alcohols such as xylitol or erythritol. Coolants or temperature control agents provide good thermal conductivity with slow endothermic and fast thermal diffusion properties, and contact cold by providing fast thermal conduction through the body.

Multilobe Cross Sections Polyamide fibers of the present invention have a multilobe cross section characterized by having at least two coalesced centers and at least five equally sized elliptical lobes, each coalesced. The center connects at least three equal-sized elliptical lobes according to angular symmetry between adjacent equal-sized elliptical lobes.

In the polyamide fibers of the present invention, a "lobe" is understood to be an elliptical portion/area of the cross section of the fiber connecting at least one coalescing center.

In the polyamide fiber of the present invention, the "merging center" is understood as the confluence of at least three lobes.

According to a preferred embodiment, the multilobe cross section has between 2 and 6 coalesced centers, preferably 2 or 3 coalesced centers, each coalesced center being 120 between each adjacent lobe. Symmetrically connecting 3 or 4 equally sized elliptical lobes according to an angle of 90° or 90°, the best result is that each merged center has 3 lobes according to an angle of 120° between adjacent lobes. Obtained when symmetrically connecting elliptical lobes of equal size.

A schematic example of a multi-lobed cross section is shown in FIG. In FIG. 1, there are three coalesced centers indicated by the letter a, and b represents a lobe, in this particular example there are seven lobes. c represents the 120° angle reproduced between each adjacent lobe.

Another cross-sectional profile is shown in FIG. 3, in which the inventive profile is illustrated by “A” to “F” (120° symmetry) and “I” and “J” (90° symmetry). There is. Contours "G", "H", and "K" are shown for comparison only.

If it has a multi-lobed cross section with at least two merged centers and three lobes arranged with 120° angular symmetry, it means that all adjacent lobes are connected at an angle of 120°. Means that For example, two coalesced centers have a total of five lobes, three coalesced centers have a total of seven lobes, and so on. The number of lobes is “(N*2)+1” for any number of “N” in the merged center.

A multilobe cross section with at least two merged centers of four lobes arranged with 90° angular symmetry means that any adjacent lobes are connected at 90°. For example, two coalesced centers connect 7 lobes, 3 coalesced centers connect 10 lobes, and so on. The number of lobes is "(M*3)+1" for any number of "M"s in the merged centers. The lobes are angularly symmetric, which means that any adjacent lobes are connected at 90°.

Therefore, the total number of cross-section lobes may be 5 (image “A” in FIG. 3) to 13 (image “F” in FIG. 3). The best cross-section sharpness and workability is for cross-sections with an adjacent lobe angle of 120°, and more specifically two with five lobes and seven lobes, respectively (see image "Fig. 3"). A") and three (image "B" in FIG. 3) coalescing centers.

Asymmetric cross-sections such as samples "G" and "H" in Figure 3 exhibit poor workability and should be avoided. These cross-sections are shown for comparison only and are conventional circular cross-sections, as is sample “K” in FIG. 3, which does not belong to the invention. Generally, flat cross sections such as “G” and “H” in FIG. 3 are more difficult to process.

The particular multi-lobed cross section of the present invention produces a special fine and continuous concave surface along the length of the fiber. The capillarity and greater surface area of the fibers of the present invention increase water absorption, diffusivity, and drying rate, thereby improving moisture management and comfort of textiles made therefrom. A less dense thread is obtained that contributes to the creation of more voids inside the filament, which improves thermal insulation, capillarity, and the thermoregulatory function of textiles made therefrom.

The larger surface area of the cross-section of the present invention allows for sweat diffusion, which greatly contributes to faster sweat evaporation. As such, the textile articles produced therefrom dry more quickly, keeping the wearer comfortable and dry during exercise. As a result, the thermal insulation of the textile articles produced from it is maintained, which avoids the effect of a damp cloth which makes you feel chills after exercise.

In contrast to the elastic nature of circular and trefoil cross sections (Y-shaped), the texture and softness are also significantly improved due to the smaller bending stiffness caused by the irregular and preferred bending direction of the cross section. A similar phenomenon of softness is also observed in the "bean" type cross section of cotton fibers. For example, “Image “B” in FIG. 3 has a preferred bend direction to a deeper concave surface.

The polyamide fibers of the present invention preferably have an overall dtex of about 40-300, about 0.1-5 dpf (dtex per filament), a tensile strength (at break) of 20-80 cN/Tex, and 20%. It has an elongation (at break) of 90%.

Method for Obtaining Polyamide with Improved Comfort Management First Embodiment: Raw Yarn The present invention also provides a method for obtaining polyamide fiber with improved comfort management as described above. Polyamide fibers are obtained by melt spinning extrusion. "Melt-spinning extrusion" is understood to mean an extrusion process that converts a polyamide into polyamide fibers. The polyamide can be fed to the melt spinning device in pellet, powder, or melt form. The method comprises any conventional extrusion spinning means suitable for melt-spinning extrusion of polyamides, such as single-screw extruders, twin-screw extruders, two-component extruders, and lattice-type spinning heads, which means are known to those skilled in the art. Is well known to. Melt spinning extrusion can be done as LOY (low draw yarn), POY (semi-draw yarn), FDY (fully drawn yarn), FOY (fully drawn yarn), LDI (for low denier industrial) or HDI (for high denier industrial). It can be further defined.

Melt spinning extrusion advantageously comprises the following steps:
a1. Feeding a polyamide composition containing a hygroscopic polyamide in the form of a melt, pellets or powder into the inlet of a screw extruder,
a2. Melting, homogenizing and pressing the polyamide composition,
a3. Spinning the molten polyamide composition into fibers,
a4. The process of cooling and winding the fiber.

In step a1, the hygroscopic polyamide is preferably continuously introduced as a melt, pellets or powder into the inlet of the screw extruder. In step a2, the polyamide is preferably melted, homogenized and pressed in a screw extruder at a temperature of 260-310° C. and an extrusion pressure of 30-70 bar, preferably above the melting point of the polyamide.

Then, according to step a3, the molten polyamide is used, preferably using a spinning screen pack comprising a filter element and a spinneret, at a temperature of 260 to 310° C., a spin pack pressure of 150 to 250 Bar, and 3 to 8 kg/hour. It is spun into fibers (or yarns or filaments) at the spin pack flow rate.

To obtain a multi-lobed cross section with a merged center, elliptical lobes of the same size, and angular symmetry, it is necessary to use a special spinneret during step a3.

A spinneret is a metal plate that contains orifices used to extrude polymer into a desired cross-sectional shape and size.

A special spinneret is a multi-lobed orifice in which each orifice has at least two merged centers, at least five equally sized elliptical lobes, and angular symmetry between adjacent equally sized elliptical lobes. including.

The multilobe orifice preferably has 2 to 6 merged centers, each merged center having 3 or 4 equally sized ellipses according to an angle of 120° or 90° between adjacent lobes, respectively. The shape lobes are connected symmetrically.

The best results have 2 to 6 coalesced centers, preferably 2 or 3 coalesced centers, each coalesced center having 3 equal dimensions according to an angle of 120° between adjacent lobes. Is obtained with a multi-lobed orifice that symmetrically connects the elliptical lobes of the.

A schematic, example of a special spinneret orifice is shown in FIG. In FIG. 2, there are three coalesced centers indicated by the letter a, b corresponds to a lobe, and in this particular example there are seven lobes. c corresponds to the 120° angle reproduced between each adjacent lobe.

For each orifice of the spinneret of the present invention, "lobe" means that the molten polymer passes through it during extrusion to form solid filaments after cooling, which form the elliptical portion/area of the cross section of the fiber. It is understood to be an area, an orifice, or a hole.

For each orifice of the spinneret of the present invention, the "merged center" means the point of at least three lobes through which the molten polymer will pass during extrusion, but which will join at least three lobes after coalescence. Is understood to be.

A merged center of the spinneret orifice and an elliptical lobe of equal size are needed to obtain good polymer distribution in the orifice during extrusion, while angular symmetry is cross-sectional stability, shape, and sharpness. Guarantee and enhance fiber grooves and capillarity.

A multi-lobed cross-section with the merged centers of three lobes connected at an angle of 120° is shown in images “A”-“F” of FIG. A multi-lobed cross section with the merged centers of four lobes connected at a 90° angle is shown in images “I” and “J” of FIG.

The coalescence phenomenon is well understood by those skilled in the art, which is the process by which two or more distinct parts (also called lobes) fuse together when contacting to form a single part. As such, the lobes do not connect within each other within the spinneret, but instead fuse together portions of the lobes during extrusion to form a single continuous filament. The merged center is then the center of the separate lobes of the invention, in particular 3 or 4 lobes.

The best sharpness and workability of the cross section is obtained with symmetrical contours with an angle between adjacent lobes of 120°. More specifically, two (sample "A") and three (sample "B") coalesced central cross sections having "5 lobes" and "7 lobes" respectively.

Each set of lobes from the sample of Figure 3 corresponds to a single continuous filament after extrusion, which is bound by the coalescence phenomenon. The total number of orifices (set of lobes) in the spinneret can be designed to produce threads of 10-200 filaments. The lobes have an elliptical shape and are exactly the same size.

Step a4 is a step of cooling the fiber (or thread or filament) to a solidified form and winding the polyamide fiber around a bobbin. Spinning oil may be added onto the fibers in this step. The winding speed is 3000 m/min to 6500 m/min.

In the present invention, the extruder may be equipped with a metering system to introduce the polymer and optional additives (masterbatch, etc.) into the base polymer in steps a1 and/or a2 and/or a3. ..

Additional additives may be incorporated into the process of the invention or may be present in the hygroscopic polyamide polymer. The additives are listed above. These additives are usually added in the polymer or in the steps a1 and/or a4 of the melt-spinning extrusion in an amount of 0.001% to 10% by weight of the polyamide fiber.

In an additional embodiment of the invention, a cooling or temperature regulating agent is also introduced in step a1 separately from the hygroscopic polyamide using a dosing device such as a gravimetric or volumetric feed pump. The cooling or temperature regulating agent may be in the form of a powder, liquid or solid masterbatch. Coolants or temperature regulators are advantageously introduced in an amount of 0.5% to 20.0% by weight, preferably 1.0 to 5.0% by weight, based on the total weight of the polyamide fibers.

Second Embodiment: Textured Yarn According to a second embodiment of the present invention, the polyamide fiber obtained from the first embodiment has a textured yarn of greater elasticity, bulk and softness. It is then textured for manufacturing. This method includes any technique known to those skilled in the art, such as false twisting, false twist-fixing, and air jet processing. Most preferred is false twisting.

The method comprises the following steps:
b1. The fiber is removed from the package and passed through a delivery roll,
b2. The fiber passes through the heater and then enters the cold zone,
b3. The process in which the fibers pass through a spindle containing a rotating disc (friction agglomeration),
b4. The step of applying confounding points and Corning oil to the fibers,
b5. It may include the step of winding the fiber on a bobbin, wherein the fiber is provided with a draw ratio by varying the speed ratio of b1 and b5.

In step b1, the fibers are preferably arranged in creels and unwound from the bobbins into delivery rolls. Step b2 preferably passes the fibers through a heater at a temperature of 120°C to 400°C to assist the mechanical action of stretching and twisting the fibers by softening (making them more conformable). Including that. After that, the fibers are cooled.

Step b3 is a place where twist, bulk, crimp, and texture occur in the fiber. The amount of twist is changed by changing the disc speed, disc placement, and D/Y relationship. The D/Y ratio changes the velocity ratio between the friction disc and the linear velocity of the fiber. This ratio is preferably 1.0 to 2.8. The arrangement of the disks is preferably 1/2/1 to 1/8/1, guide disk/actuating disk/guide disk.

In step b4, the fibers are provided with an entanglement point and a Corning oil to impart lubricity and to improve physical and aesthetic properties (in the case of entanglement). Entanglement per meter is preferably at least 30 per meter. Step b5. Is a winding process, where the fibers are wound on a bobbin. The winding speed can vary from 150 m/min to 1500 m/min.

The draw ratio is imparted to the fiber by varying the speed ratio of step b1 and step b5, which is an important parameter of the process to achieve the desired linear density. The draw ratio is preferably 1.10 to 4.00. Threads larger than 1 ply, such as 1-8 plies, are also possible.

Polyamide Articles The polyamide fibers of the invention can then be converted into polyamide articles, especially woven fabrics and/or garments. The polyamide article of the invention is manufactured from the polyamide fibers of the invention (as defined above) or from the polyamide fibers obtained from the method of the invention, preferably fibers, multifilament yarns, flocs. , Woven, knitted, non-woven, or textile articles.

The textile article may be any textile article known in the art such as, but not limited to, woven fabrics, knitted fabrics, nonwoven fabrics, ropes, strings, sewing threads, and the like. For clothing, the best results are achieved with a fabric having a mass per unit area of less than 200 g/m ² , most preferably less than 150 g/m ² .

Methods for Obtaining Polyamide Articles Methods for converting polyamide fibers into polyamide articles such as woven fabrics or garments are well known to those skilled in the art. In fact, the polyamide fibers can be converted into polyamide articles by texturing, drawing, warping, knitting, weaving, non-woven, sewing, or combinations thereof. These articles continue to be used in many applications, especially in socks, underwear, sportswear, outerwear, and leisure wear.

Advantages Additional advantages of the polyamide fibers with improved comfort management of the present invention and articles made therefrom are highlighted below:
-In the present invention, a novel polyamide 5.6 fiber is disclosed which has essentially hygroscopic properties and a capillarity effect. In contrast to the chemically modified hydrophilic polyamides offered on the market.
-In the present invention, a novel multi-lobed cross-sectional profile is disclosed.
-The polyamide article shows a faster rate of water absorption, wicking, and drying when compared to a non-hygroscopic polyamide of circular cross section.
-The synergistic effect of hygroscopicity, capillarity, and larger surface area of the cross-section accelerates the drying rate of water, so that the wearer feels dry and is comfortable even after intense sweating.
-The mechanical and chemical properties of the polyamide article do not change significantly.
-The method is simple and utilizes conventional, well-known extrusion equipment.
-The cross-sectional profile of the present invention significantly improves the feel and softness of the fibers due to the smaller bending stiffness caused by the irregular and preferred bending directions, as opposed to the elastic nature of circular and trefoil cross-sections. To do. A similar phenomenon is observed with a "bean" type cross section of cotton fiber.

Background of Comfort and Methods of Evaluation Although comfort is a complex phenomenon, it can be generally classified into four different main aspects: a) Thermophysiological comfort depends on the wearer. Affects temperature regulation, which involves the process of heat and moisture transfer through clothing. Key concepts include thermal insulation, breathability, and moisture management capabilities; b) Sensory comfort on the skin characterizes the mechanical sensation that the textile produces directly in contact with the skin and is comfortable. Sensations include smoothness and softness, while discomfort may be tingling, over-gritting, or sticking to sweaty skin; c) ergonomic comfort may be It deals with compatibility and the freedom of movement it allows. This mainly depends on the pattern of the garment and the elasticity of the material; d) physiological comfort is influenced by fashion, personal preference, conceptual form, etc.

Thermophysiological comfort is based on the principle of energy conservation. All of the energy produced in the body by metabolism is in exactly the same amount due to heat loss by the respiratory system (breathing), dry heat flux (including radiation, conduction and convection), and the heat flow from evaporation caused by sweating. Have to be dissipated from. If more energy is produced than is dissipated, the body becomes hyperthermic. Also, if the heat loss is too large, hypothermia occurs.

Comfort is by no means the result of only one parameter, but rather it is a result of the composition of the fibers, the structure of the fabric, the system of layering of the garment, the chemical conversion treatment, etc. Studies have revealed that the structural parameters of the dough and the conversion treatment are as important as the fiber composition. For example, for textiles for sports, in addition to hydrophilicity and quick-drying, lightweight, porous and thin fabrics are desirable. Water vapor diffuses through the spaces between the threads, the spaces between the fibers, the fiber material itself, and the open voids in the textile.

The chemical conversion treatment mainly includes a treatment for the purpose of hydrophilicity, which aims to increase the hydrophilic property of the hydrophobic fiber product. A disadvantage of the conversion treatment is that it is a non-durable treatment and can only last for several home laundry cycles. On the other hand, fibers with essential moisture management properties last for the entire life of the textile article.

With regard to the composition of the yarn, the use of filament yarn results in direct contact with the overly smooth and flat textile surface. This structure shows too many points of contact with the skin, and the fabric is perceived to be too smooth and stick to sweaty skin. While filament raw yarns have a poor feel to the touch, spun or textured yarns give a better feel. Textured yarns provide less contact with the skin, greater insulation, softness, and a pleasant hand feel. In the spun and textured yarn more protruding 3D structures as well as protruding fiber ends are created, which act as spacers between the skin and the textile. In order to increase the wicking rate and surface area, the cross section of the yarn with grooves along the filaments, holes, and capillarity channels is also important, which gives rise to wicking and faster drying rates.

Air is also an important feature of clothing. Air is welcomed not only for its light weight but also for temperature control. The layer of air between clothing and skin helps reduce temperature fluctuations. By reducing the points of contact between the skin and clothing, air circulates freely and allows the body to breathe.

Moisture management properties are usually evaluated by water absorption, vertical wicking, horizontal wicking, breathability, water vapor permeability, heat resistance, and drying rate. The AATCC 195 standard of the "American Association of Chemists and Colorists" can be used to measure the liquid moisture management properties of textiles. Water absorption can be evaluated by AATCC 79. Vertical wicking of textiles is typically assessed by AATCC 197, while horizontal wicking can be assessed by AATCC 198. AATCC 199 and AATCC 200 can be used to measure the dry time of textiles under various conditions using a moisture gravimetric analyzer. Alternatively to the above method, heat to assess comfort, such as by using a heated hot plate (ASTM F 1868; ISO 5085-1, 1989; ISO 11092, 1993), a thermal mannequin, and a human test. -Physiological and sensory tests are also available.

Other details or advantages of the invention will emerge more clearly from the examples given below.

A series of polyamide articles, including a comparative polyamide article and a control polyamide article, were formed to process performance, water wicking rate, water absorption rate, water drying rate, hygroscopicity, mechanical properties, IVN (viscosity index), ATG (end. Amino group) and CTG (carboxyl terminal group) are evaluated. Samples are summarized in Table 1.

Amino end group content (ATG)
Amino end group (ATG) content was determined by potentiometric titration. An amount of 2 g of polyamide is added to about 70 ml of about 90% by weight phenol. The mixture is kept at a temperature of 40° C. with continuous stirring until the polyamide is completely dissolved. The solution is then titrated with 0.1 N HCl at about 25°C. Results are reported in equivalent weight/ton (eq/ton). When analyzing fibers and articles, any residue or spin finish must be removed beforehand.

Solution viscosity (IVN)
The solution viscosity (IVN) is determined according to ISO307. The polyamide is dissolved in 90% by weight formic acid at 25° C. at a concentration of 0.005 g/ml and its flow time is measured. Results are reported as ml/g.

Carboxyl end group content (CTG)
Carboxyl end group content (CTG) was determined by titration method. An amount of 4 g of polyamide is added to about 80 ml of benzyl alcohol. The mixture is kept at a temperature of 200° C. with continuous stirring until the polyamide is completely dissolved. The solution is then titrated with 0.1 N potassium hydroxide in ethylene glycol. Results are reported in equivalent weight/ton (eq/ton). When analyzing fibers and articles, any residue or spin finish must be removed beforehand.

AATCC 195-Liquid water management of textiles (evaluation of horizontal water wicking speed and water absorption time)
Liquid moisture management properties are evaluated by sandwiching a dough sample between two horizontal (upper and lower) electrode sensors. A predetermined amount of the test solution that promotes the measurement of the change in conductivity is dropped on the center of the surface of the test specimen facing up. The test solution is free to move in three dimensions: radial spread at the top, movement through the specimen from top to bottom, and radial spread at the bottom of the specimen. During the test, the change in electrical resistance of the specimen is measured and recorded. This method uses a moisture management test meter (MMT). Water absorption results (sec) and water diffusion rates (mm/sec) are shown by this method.

AATCC 199 Liquid Water Drying Rate Water is applied to the test specimen (0.1 ml), then the specimen is placed on a scale and dried for 40 minutes. The drying rate is continuously monitored and recorded by the dry tester software. Results are reported in mg/min sample area of water (mg/min*inch ² ).

Vertical Wicking of AATCC 197 Textiles Visual observation of liquid velocity (distance per unit time) traveling along and/or through vertical fabric specimens, manually timed and recorded at specific intervals To do. This test method considers the effects of gravity when assessing wicking.

Hygroscopicity A sample of about 2 g is placed in a weighed bottle and dried at 105° C. for 2 hours (weight W3). Then, the weighed bottle is placed in a climate test chamber at 20° C. and 65% RH for 24 hours. The weight of the sample is measured again (weight W1). The weighed bottle is then placed in a climate test chamber at 30° C. and 90% RH for 24 hours. The weight of the sample is measured again (weight W2). The hygroscopic delta is measured by the following formula: MR1=(W1-W3)/W3, MR2=(W2-W3)/W3. The difference in water absorption rate is obtained by Λ MR (%)=MR2-MR1.

Evaluation of texture The evaluation of touch was subjectively evaluated using "HESC Standard of Hand Evaluation-Second Edition". This is a method developed by "Hand Evaluating and Standardization Committee" of "Japan Textile Machinery Society". The sensation with the fingers when the sample is touched by the hand is evaluated by comparison with a standardized reference sample of the procedure. These characteristics include "koshi", "nulliness", "bulge", "softness", "smoothness", "compressibility", and the like. A THV (Comprehensive Texture Value) rating of 1 to 5 is given, 5 being "very good" and 1 being "very bad".

Examples A-I-Multilobe Cross Section Studies Various multilobe cross sections were investigated in the context of melt spinning capabilities. Polyamide 6.6 pellets were used for the samples. Polyamide 6.6 pellets were prepared by polymerizing a nylon salt containing primarily hexamethylenediamine and adipic acid. The IVN (viscosity index) measured by the method disclosed herein is 128-132 and the ATG (amine end group) is 40-45. A multifilament yarn was produced. A sample summary is shown in Table 2.

Examples 1-8-Filament Sample PA 5.6-Examples 1, 2, 3, and 6
Polyamide 5.6 fibers were prepared from polyamide 5.6 pellets using a spinneret containing a multi-lobed cross section for Examples 2 and 3 or a spinneret containing a round orifice for Examples 1 and 6. Was produced by melt spinning extrusion. Polyamide 5.6 pellets is a polyamide commercially available from Cathay Biotech under the trademark Terryl®. IVN measured by the methods disclosed herein is 138-142, ATG is 38-42, and CTG is 65-75.

In step a1, the polyamide composition was fed in the form of dry pellets into the inlet of the screw extruder. In step a2, the polyamide was melted, homogenized and pressed in a screw extruder at a temperature of about 290° C. and an extrusion pressure of about 50 bar. Then, in step a3, the molten polyamide blend was spun into a multifilament yarn at a spin pack pressure of about 200 bar and a spin pack flow rate of about 5 kg/hr. In step a4, the polyamide fiber blend was solidified and wound on a bobbin at about 4200 m/min.

PA6.6-Examples 4, 5, and 7
Polyamide 6.6 fibers were melted from polyamide 6.6 pellets using a spinneret containing a multi-lobe cross section for Example 5 or a spinneret containing a round orifice for Examples 4 and 7. Prepared by spin extrusion in the same manner as described in Examples 1, 2, 3, and 6 above.

Polyamide 6.6 pellets were prepared by polymerizing a nylon salt containing primarily hexamethylenediamine and adipic acid. The IVN (viscosity index) measured by the method disclosed herein is 128-132 and the ATG (amine end group) is 40-45.

PA 6.10-Example 8
Polyamide 6.10 fibers were produced in the same manner as described in Examples 1, 2, 3, and 6 above by melt spinning extrusion from polyamide 6.10 pellets using a spinneret containing a round orifice. did. Polyamide 6.10 pellets are polyamides sold under the trademark STABAMID (copyright) by Solvay Group. IVN measured by the methods disclosed herein is 102-118 and ATG is 49-57.

Examples 1.1-4.2-Textured yarn samples The multifilament yarns obtained above (Samples 1, 2, 4, 5, 6, and 7) are further textured to a linear density of 1x80f68 dtex ( For example 1.1, 2.1, 4.1, 5.1, 6.1, and 7.1). The multifilament yarn obtained above (Samples 1 and 4) is further textured to a linear density of 2x80f68 dtex (eg 1.2 and 4.2).

In all of the above examples, a similar knit fabric is made to perform the moisture management test. Sample details and a summary of mechanical results are shown in the table below.

Result 1. Investigation of machinability of multi-lobe section

2. Investigation of water absorption of polyamide

3. Survey on water management of raw yarn samples

4. Investigation of moisture management of textured yarn samples

5. Vertical wicking of fabric

6. Investigation of the effect of cross section on texture

Conclusion First, multiple cross sections were investigated to select the most appropriate one in consideration of workability (Table 2). The multilobe configuration with an angle of 120° between the lobes showed the best melt spinning performance (Samples A, B, C, D, F). On the other hand, a flat cross section or a cross section with small symmetry showed poor workability (Samples E, G, H). Therefore, samples "A" and "B" were used for the comfort control experiments of the present invention.

Next, when the hygroscopicity of the three polyamides was analyzed, polyamide 5.6 showed the best results. In fact, it was found that the hygroscopicity was surprisingly high (5.1% in Table 3, sample 1.2).

The yarn was then investigated for water management properties, termed water absorption, water drying, and water wicking. The results are summarized in Table 3. Comparing sample 2 (invention) and sample 4 (comparative example), the water drying rate was increased by 79%, the water absorption was improved by 89%, and the water wicking rate was increased by 26 times (or 2600%) You can observe what you have done. Threads with less coarse filaments (higher dtex per filament) such as 100f23 tend to be more uncomfortable to the skin than threads with more and thinner filaments (100f68). However, the results of Samples 6 and 7 (100f23) showed very good water management, eg 96% greater water absorption, 78 times greater water wicking rate, due to the hygroscopic nature of polyamide 5.6. These are expected to be further increased by providing a multi-lobed cross section. Therefore, the wicking property was significantly improved.

The improved multi-lobed cross section plays a major role in this improvement and comparing sample 1 (control) and sample 2 (invention) increases water drying rate by 9% and water absorption by 40%. However, it was found that the water wicking rate increased by 24%. The results for polyamide 6.10 (Sample 8) are also shown for comparison, with very poor hydrophilicity giving very poor results.

The same properties were analyzed for the textured yarn (Table 5). As textured yarns have more crimp, texture, bulk, elongation and twist, they provide greater softness, comfort, insulation and are more pleasing to the skin. The results of samples 2.1 (invention) and 4.1 (comparative) showed an improvement in water drying rate of 15%, water absorption of 22%, and wicking rate of water of 46%. The multi-lobed cross section also contributed to this improvement by comparing Sample 1.1 with Sample 2.1, with water drying rate increased by 9%, water absorption increased by 11% and wicking rate increased by 7%. is there. The results with less filament yarn (6.1) and 2x ply (1.2) showed a significant improvement in relation to samples 7.1 and 4.2, respectively. The term 2x80f68 means that two yarns bond during the texturing process, so the resulting linear density is twice that of 1x80f68.

A vertical wicking test was also conducted to further analyze the wicking characteristics considering gravity for the purpose of understanding the effect of the multi-lobe type cross section. Again, a significant improvement was observed by comparing the results in Table 6 (Samples 1 and 2), which gave a surprising increase of 29%.

It can also be concluded from the results in Table 7 that the cross-sectional profile of the present invention improves the texture and softness of the fibers due to the low bending stiffness, the preferred bending direction and the lower yarn package density.

Thus, the results show that in the present invention, a novel polyamide having essential hygroscopic properties and comfort is disclosed, in which the polyamide article is more likely to be compared to a non-hygroscopic polyamide having a circular cross section. It can be seen that it exhibits a fast rate of water absorption, wicking, and drying. In addition, the synergistic effect of hygroscopicity, higher surface area cross-section, and capillarity accelerates the drying rate of water, so that the wearer feels dry and is comfortable even after intense sweating. The results are summarized below.

The overall advantages of polyamide fibers and articles made from them include the following:
-Optimal hygroscopicity for absorbing perspiration without the feeling of being wet and maintaining ideal thermal insulation in the clothing climate.
-Enhanced wicking speed to carry sweat away from the skin efficiently.
-A fast drying rate to keep the skin dry and avoid the unpleasant chilly feeling after exercise.
-The mechanical and chemical properties of the polyamide article do not change significantly.
-The method is simple and utilizes conventional, well-known extrusion equipment.
-The cross-sectional profile of the present invention also significantly improves the feel and softness of the fiber due to the novel multilobe type features disclosed.

Claims (19)

Polyamide 5. Having improved comfort management, including hygroscopic polyamides, which are bio-based aliphatic polyamides selected from the group consisting of X (where X is an integer from 4 to 16) and mixtures thereof. a polyamide fiber, has a multi-lobed cross-section characterized by having a b over Bed of at least five equally sized and at least two coalesced center, center of the respective combined, adjacent lobes Polyamide fibers symmetrically connecting three equally sized lobes according to an angle of 120° between them . The hygroscopic polyamide is polyamide 5. Polyamide fiber according to claim 1, which is X, where X is an even number from 4 to 16, preferably 6 or 10. The polyamide fiber according to claim 1, wherein the hygroscopic polyamide is polyamide 5.6. Polyamide fiber according to any one of claims 1 to 3, comprising more than 75% by weight, preferably more than 85% by weight and more preferably more than 95% by weight of hygroscopic polyamide, based on the total weight of the fiber. The multi-lobed cross section, and have a 2-6 coalesced center, polyamide fiber according to any one of claims 1-4. The multi-lobed cross section, and have a two or three coalesced center, polyamide fiber according to any one of claims 1-5. A method for obtaining a polyamide fiber with improved comfort management according to any one of claims 1 to 7 , wherein the polyamide fiber is according to any one of claims 1 to 4. A method obtainable by melt spinning extrusion of a polyamide composition comprising a hygroscopic polyamide. The melt spinning extrusion comprises the following steps:
a1. Supplying the polyamide composition containing the hygroscopic polyamide into the inlet of a screw extruder in the form of a melt, pellets, or powder;
a2. Melting, homogenizing, and pressing the polyamide composition,
a3. Spinning the molten polyamide composition into fibers,
a4. Cooling and winding the fibers,
Step a3 is achieved through at least one spinneret comprising a multi-lobed orifice, each orifice, at least two coalesced center, at least five equal dimensions B over blanking, and centers were each combined, Symmetrically connect three equally sized lobes according to a 120° angle between adjacent lobes,
Wherein the fiber is obtained by coalescence, the center was the coalescence, the following angular symmetry between Russia over blanking of adjacent equally sized connecting the B over Bed of at least three equal size, according to claim 7 Method. The multi-lobed orifice is closed 2-6 coalesced center, The method of claim 8. The multi-lobed orifice is have a two or three coalesced center, The method of claim 8. Next steps:
b1. Removing the fibers from the packaging and passing through a delivery roll,
b2. Passing the fiber through a heater and then into a cold zone;
b3. Said fibers passing through a spindle containing a rotating disc (friction agglomeration),
b4. A step of applying confounding points and Corning oil to the fibers,
b5. 11. The yarn according to any one of claims 7 to 10 , further comprising a false twisting process including a step of winding the fiber around a bobbin, and changing the speed ratio between step b1 and step b5 to give the yarn a draw ratio. The method according to paragraph 1. According according to any one of claims 1 to 6, or claims 7 to resulting from the process according to any one of 11, polyamide article comprising the polyamide fiber having improved comfort management. The polyamide articles are manufactured from claims according to any one of claims 1 to 6, or claims 7 to resulting from the process according to any one of 11, polyamide fibers with improved comfort management 13. A polyamide article according to claim 12 , which is a stapled fiber, staple fiber, flock, woven fabric, knitted or non-woven fabric, or a textile article. Raw with a tensile strength of 20-80 cN/Tex (at break), an elongation of 20-90% (at break), a linear density of 40-300 dtex, and a dtex per filament of 0.1-5.0. 14. A polyamide article according to claim 12 or 13 which is a multifilament yarn of or of textured. 14. Polyamide article according to claim 12 or 13 , which is a dough and the mass of the polyamide dough per unit area is less than 200 g/m< ² >, preferably less than 150 g/m< ² >. The polyamide article according to any one of claims 12 to 16 , which is a textile article or a part of a textile article and constitutes at least 30% by weight of the total weight of the textile article. According according to any one of claims 1 to 6, or to any one of claims 7 to 11 resulting from the process described, polyamide fibers warping having improved comfort management, knitting process, The method for obtaining a polyamide article according to any one of claims 12 to 16 , which is converted by weaving, non-woven processing, sewing, or a combination thereof. In order to improve the comfort management of the polyamide fiber obtained from the method according to any one of claims 1 to 6 or from the method according to any one of claims 7 to 11 of a polyamide article produced therefrom. Use of. 19. Use according to claim 18 , wherein the polyamide article is a textile article.