JPH03124857A - Lightweight fabric excellent in heat insulating property and its production - Google Patents

Abstract

PURPOSE:To obtain the subject thin-gage and lightweight fabric, excellent in heat insulating properties and useful for inner wears, etc., by constructing a fabric from filament yarn composed of polyester.polyamide sheath-core type conjugate fiber and then treating the resultant fabric with a heated aqueous solution of an alkali. CONSTITUTION:The objective fabric, obtained by constructing a fabric from filament yarn at least consisting essentially of polyester.polyamide sheath-core type conjugate fiber having a sheath part 1 consisting of a polyamide and a core part 2 composed of a polyester at (25/75)-(70/30) conjugate ratio by wt.% and treating the fabric with a heated aqueous solution of an alkali and having the basis weight (Wg/m<2>), thickness (Amm) and CLO value (C) which is a measure of heat insulating properties of the fabric simultaneously satisfying 40<=W<=100, 0.25<=A<=0.35 and C>=0.65. Furthermore, the ratios of the polyamide sheath part 1 (x%), polyester core part 2 (y%) and hollow part 3 (z%) in the fiber cross section preferably satisfy 25<=x<=70, 10<=y<=65 and 10<=z<=60 at the same time.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a thin and light fabric that has excellent heat retention properties. In particular, it relates to a heat-retaining lightweight fabric useful as innerwear.

[Prior Art] Synthetic fibers, especially thermoplastic synthetic fibers such as polyamide and polyester, are produced and consumed in quantities comparable to natural fibers due to their excellent strength and easy care properties.

However, because these thermoplastic synthetic fibers, especially polyamide filament yarns, have a uniform and simple surface and internal structure, simple round-section filament yarns have a cold or waxy feel, and are not suitable for warmth or warmth in winter clothing. It has the disadvantage of insufficient heat retention.

Therefore, attempts have been made to improve the above-mentioned drawbacks by creating textured yarns such as spun yarns, complicating yarn cross sections, and false twisting, and many products have been made into cloth. However, these conventional means have problems in that they lack a soft feel and are difficult to make sufficiently thin.

In addition, Japanese Patent Laid-Open No. 63-6130 proposes that a thin fabric is constructed using polyamide/polyester splittable composite fibers only for the weft to balance flexibility, stiffness, and tension. In this method, since polyamide ultrafine fibers and polyester ultrafine fibers coexist, resulting in a high-density fabric, there is a problem in that the amount of air taken into the fabric is small and it is difficult to obtain sufficient heat retention. Moreover, since acid dyes and disperse dyes (JF) are used for dyeing, irritation is likely to occur due to differences in dyeing, and the disperse dyes dyed on polyamide have poor dye fastness, making it difficult to dye the resulting product. There is also the problem that the fastness is unsatisfactory for practical purposes.

On the other hand, hollow fibers, which have a hollow layer inside the fibers, have properties such as bulkiness, heat retention, stain resistance, water absorption, and filtration properties, so they have been used for a variety of purposes by taking advantage of these characteristics. . For example, polyester stuffed cotton that takes advantage of bulk and heat retention; polyester staple fiber that takes advantage of waist, tension, and heat retention; acrylic stable fiber that takes advantage of water absorption; carpet yarn that takes advantage of stain resistance; etc. It is being used.

However, in the case of ordinary polyamide fibers such as nylon 6 and nylon 66, it is difficult to increase the hollowness ratio because they are manufactured by melt spinning, and the modulus of the polymer itself is low, so it is difficult to increase the hollowness in the post-processing process. Since the hollow portions are easily crushed, polyamide hollow fibers have only been used as thick antifouling carpet yarns.

In addition, a method was proposed in JP-A-56-112569 to make it possible to manufacture fine-grained hollow fibers with large hollow parts from polyamide, and the method was proposed in Japanese Patent Application Laid-Open No. 112569/1983, which produced a texture similar to non-slimy cotton and a unique texture with a crunchy texture. It is disclosed that a product having 1q is produced. However, this publication exemplifies the use of hollow composite fibers having a relatively thin polyamide sheath layer with a composite ratio of 20% in yarn yarns that are relatively thick for clothing in order to improve the feel of fabric products. Therefore, the hollow composite fiber structure could not be fully utilized as a heat-retaining material.

[Problems to be Solved by the Invention] Therefore, the present invention aims to provide a highly heat-retaining, lightweight fabric that has excellent fashionability and has a high heat-retaining property comparable to that of wool, and is as thin and light as a feather. Make it the main purpose.

That is, the main objective is to provide a novel fabric product that can fully utilize the polyamide-based hollow composite fiber structure proposed in the above-mentioned publication as a heat-retaining material.

Another objective is to provide a highly heat-retaining, lightweight fabric that has appropriate elasticity and tension, the soft touch characteristic of polyamide, good dyeability and durability, and also has excellent dimensional stability. .

[Means for Solving the Problems] In order to achieve this object, the present invention according to claim 1 provides a sheath made of polyamide, a core made of polyester, and a hollow space between the sheath and the core. A fabric composed of core-sheath type hollow composite GI fibers having a core-sheath type hollow composite GI fiber, and
The fabric weight (Wg/Tr12) and thickness (A mm
”) and CLO value (C) are 40≦W≦100.0
．． 25≦A≦0.35C≧0.65, and the method of the present invention according to claim 4 also provides a composite material comprising a sheath made of polyamide and a core made of polyester. The ratio (wt%) is 2
5/75 to 70/30 polyester/polyamide core/sheath composite fibers as a main component, and then treated with a heated alkaline aqueous solution to produce the lightweight fabric according to claim 1. It consists of a method of manufacturing.

The lightweight fabric according to claim 1 is composed of a hollow composite fiber having a core-sheath type 3m structure consisting of a sheath made of polyamide, a core made of polyester, and a hollow part that exists as a heat insulating layer between the two. In order to satisfy the above-mentioned fabric properties and inherent fiber performance of the fabric, the proportions of the sheath, core, and hollow portion (X%, y%, and 2%, respectively) should be 25≦x≦70. .10≦y≦65. It is effective to simultaneously satisfy 10≦7≦60 (Fig. 3). This composite ratio can be measured by taking microscopic photographs of fiber cross sections of fibers taken out from the fabric.

The polyamide constituting the sheath of this hollow composite fiber is essentially polyhexamethylene adipamide (nylon 6
6) and polyε-capramide (nylon 6) are preferred, but polyamides containing sebacic acid, isophthalic acid, paraxylene diamine, etc., or copolymerized polyamides thereof, etc. may also be used. The degree of polymerization may be within the range used for general clothing.

Generally, sulfuric acid relative viscosity (ηr: 98% sulfuric acid 100cc
(value measured by dissolving 1 g of polyamide) as 2
．． About 4 to 3.5 is preferable.

In addition, even if the outer portion of the polyester constituting the core is dissolved and removed by a heated alkaline aqueous solution that has permeated through the sheath, fiber properties such as strength and elongation will not be substantially impaired, and the fiber performance such as strength and elongation will not be substantially impaired. If melt composite spinning is possible, the polymer composition is not specified, but for example, polyethylene terephthalate and polybutylene terephthalate are suitable. It may also be a polyester obtained by copolymerizing a small amount of isophthalic acid, aliphatic dibasic acid, sulfonated aromatic carboxylic acid, etc. with these.

The degree of polymerization may be within the range used for general clothing. In general, the limiting viscosity fJr (IV: value measured by dissolving polyester in orthochlorophenol) is 0.
．． The range of about 55 to 0.75 is preferable.

Note that these polyamides and polyesters may be used in addition to common fiber additives such as matting agents such as titanium oxide, ultraviolet absorbers, and antioxidants. However, if the core polyester contains titanium oxide, the titanium oxide lattice will adhere to the inner wall of the hollow part during treatment with an aqueous caustic solution.
It is preferable that the core polyester does not substantially contain titanium oxide because it tends to cause uneven gloss and foaming.

The shape and positional relationship in the cross section of the fiber of the sheath, core, and hollow part may be whatever they are, as long as the core and sheath are substantially separated by an air layer and exist independently. good. For example, a concentric three-layer core-sheath composite form as shown in FIG. ,square,
The core layer may have a non-circular shape such as a star shape, or the outer peripheral surface of the core layer may have a similar non-circular shape.
4)) Also, the core layer and the sheath layer may be relatively eccentric (FIG. 2 (5)).

The hollow composite m-fiber constituting the fabric in claim 1 is a core-sheath type composite 1 in which the composite ratio of sheath polyamide and core polyester is 25/75 to 70/30, as in the method of claim 4.
After spinning the IIi fiber, the outer part of the core polyester is partially eluted and removed using a heated alkaline aqueous solution, so that it can be made into a length of 1 m.

In the heated alkaline aqueous solution treatment for partially eluting and removing the core polyester, a caustic alkali such as caustic soda or caustic potash is used as a chemical. The treatment conditions vary depending on the thickness of the sheath, the type of polyamide or polyester, the degree of oriented crystallization of the m-fibers, and the desired hollowness ratio, but generally the concentration of caustic alkali is 10 to 100. (II/D, the temperature may be 80 to 120°C.

Further, a core-sheath type composite i-fiber having a polyester core and a polyamide sheath can be produced by the following method.

After the core polyester and the sheath polyamide are separately melted, they are introduced into the spinning back section to form a core-sheath composite flow using a conventional composite method, and are spun out from a spinning nozzle. The spun filament yarn is cooled, solidified, and oiled, then entangled if necessary, and taken off at a predetermined speed. After this take-up, the film may be first rolled up into a package and then stretched using a draw twister, or it may be stretched without being wound up and then wound up. Also, the pick-up speed is set to 4.
The product yarn may be produced at a high speed of 000 m/min or higher to have the target fiber performance at once without being drawn substantially.

It is preferable to manufacture the lightweight fabric according to claim 1 by weaving and weaving the obtained product yarn into a fabric using a normal method, and then subjecting the core to partial elution treatment. As long as the core part can be retained well, the core part may be partially eluted in the process before being made into a fabric.

The lightweight fabric according to the present invention has a low basis weight of 40 to 100 g/TIt and a thinness of 0.25 to 0.35 mm, and the basis weight (W) and fabric thickness (A) are determined by the following method. be measured.

Fabric weight: Take a 25cm x 25cm fabric test piece, dry it thoroughly until the moisture content is below the equilibrium moisture content, and then
The test piece was left in a room at 65% RH for 24 hours to achieve moisture equilibrium, and then the weight of the test piece was measured.

The weight of the obtained test piece is converted to 1 TIi, and is expressed as the average value for two fabric test pieces.

Thickness: Place the test fabric on the sample stand of a dial gauge type thickness measuring device (manufactured by Daiei Kagaku Co., Ltd.), and place 1-
A load of 7 g/- is applied using a pressa foot.
The thickness after 0 seconds was measured at 5 or more locations and expressed as the average value.

In order to obtain a fabric with such low basis weight and thinness, the proportion of hollow parts after elution and removal must be adjusted to an appropriate value (for example,
10% or more), and it is generally effective to reduce the fineness of the constituent yarns to an appropriate level.

For example, the yarn fineness of the composite fiber before alkali treatment may be 70 denier or less, further 65 denier or less. In addition, in order to obtain a fabric product with a soft texture, it is preferable that the single yarn fineness is about 1 to 10 denier.

The fabric structure of this fine-grained yarn may be any fabric normally used for clothing such as inner wear, such as tricot knit fabric, nine-knit fabric, or woven fabric.

Further, the CLO value (C) is a measure of the heat retention property of a fabric, and is measured by the following method that simulates a human body in a resting state at an environmental temperature of 13°C.

The test fabric, which had been sufficiently conditioned in an environment of 20°C and 65% RH, was placed on a 5Tr12 hot plate set at 40+0.1°C, and after 1 minute had passed, in a stable state, the test fabric was heated. The heat loss dissipated into the environment through the test fabric is determined by the hot plate area (
It is calculated from Svri and power consumption (EV). At this time, in order to prevent heat radiation from the hot plate due to convection, the area around the hot plate was covered with a resin case with an opening/closing opening at the top to maintain a windless state.

The amount of heat dissipated from a hot plate without cloth on it is proportional to the temperature difference with the environment, so considering the average temperature of the human body 33 degrees Celsius,
The above experiment with a temperature difference of 20°C simulates the heat retention of a human body in a resting state at an environmental temperature of 13°C.

The value of heat loss obtained in the above experiment is calculated by the following formula: CL
It is converted to O value (C).

C= (110,155)
Demonstrates the original functions that fabrics require, such as stretch, surface feel, and dyeability. At the same time, it allows the chemicals used in the hollowing process to pass through without being adversely affected by the chemicals, and
It also functions to allow the decomposition products of the polyester in the core to permeate to the outside and remove them.

The core made of polyester is necessary to impart functions such as dimensional stability, elasticity, tension, and wrinkle resistance to the fabric.

Further, the hollow portion is important for providing high heat retention to the fabric. Having the hollow part between the core and the sheath means that
This is effective for obtaining a stable hollow that is less likely to break or collapse, and also allows a relatively wide range of hollow proportions, making it easy to design the hollow. In general, since it is possible to stably obtain a high hollowness ratio even with fine-grained yarns, it is possible to manufacture thin fabrics using hollow fibers, and it is possible to produce thin fabrics with the fabric characteristics specified in claim 1. A lightweight fabric with high heat retention can be obtained.

That is, the lightweight fabric with high heat retention obtained by the present invention has a
Dates as low as 0-100g/m and 0.25-0
．． Despite being as thin as 35mm, the CL
It has high heat retention properties with an O value of 0.65 or more.

This CLO value is generally used as an index indicating the heat retention property of a fabric, and the larger the value, the better the heat retention property. And 21℃, 50%RH or less, air flow 5
CL is the heat retention property (thermal resistance) of a fabric that can maintain the average skin temperature (33℃) of a resting human body indoors at cm/sec.
It is expressed by an O value of 1.0.

Since the fabric according to the present invention is mainly intended for use as a thin, light, and highly fashionable clothing fabric, it is necessary to have the above-mentioned specific low date value and the above-mentioned specific thinness. Ru.

A5 fabric with this level of fabric weight and thinness is used for innerwear made of polyamide fiber M, but the fabric of conventional innerwear made of polyamide fiber has a heat retention property of C.
The LO value was quite poor at around 0.56 to 0.60, and heat retention had to be sacrificed. Furthermore, it is possible to increase the CLO value by increasing the basis weight and thickness of the fabric, but this does not satisfy fashionability. As described above, it was thought that the fabric specified in the present invention, which is lightweight yet has high heat retention properties, could not be manufactured in the past.

In order to obtain this lightweight fabric with high heat retention, the proportions of the sheath part, core part, and hollow part of the hollow composite fiber should be adjusted as follows.
It is effective to set it to 25-70%, 10-65%, and 10-60%.

In order to prevent the sheath part from tearing during use of the fabric and to fully exhibit the desirable properties inherent to the sheath polyamide (strength, dyeability, etc.), the ratio of the sheath part should be 25% or more. Also,
Effects of polyester core (fabric dimensional stability, waist,
In order to fully exhibit the properties (strength, wrinkle resistance, etc.), the proportion of the core portion should be 10% or more.

In order to make the resulting fabric have a CLO value of 0.65 or more in terms of heat retention, the proportion of hollow portions may be 10% or more.

In order to obtain this degree of hollowness, it is difficult to make the sheath and/or core too large, and the practical upper limit is about 70% for the sheath and core. It can be said that it is about 65%. In addition, if the sheath is too thick, the chemical solution will penetrate the sheath during the process of partially eluting and removing the core polyester, and it will take a long time to remove the decomposed products. It is desirable to suppress the ratio to about 70% or less.

The larger the proportion of the hollow part, the better the heat retention, but if the proportion of the hollow part is too large, the hollow part is likely to be crushed or destroyed when handling or using the fabric. Since it is difficult to determine the
The practical upper limit is about 60%.

[Example Example 1] Poly ε-capramide containing 0.3% titanium oxide fine powder (sulfuric acid relative viscosity ηr = 2.6) and polyethylene terephthalate (intrinsic viscosity) containing substantially no titanium oxide (intrinsic viscosity) V = 0.63> were melted separately in an extruder-type spinning machine, weighed at the composite ratio shown in Table 1, and arranged so that the sheath part was made of polyε capramide and the core part was made of polyethylene terephthalate. After joining into a concentric core-sheath shape with a nozzle and discharging it, it was taken off at a speed of 3,500 m/min, and then heat-set while being stretched at a speed of 5,000 m/min with a drawing row heated to 160"C, It was wound up as a drawn yarn of 40 denier and 12 filaments.

Using the obtained drawn yarn (core-sheath composite Ia fiber), a 32-gauge warp knitted fabric with a half structure was obtained by a conventional method.

After 1 q of knitted fabric was subjected to relaxation treatment and intermediate setting treatment in a conventional manner, it was immersed in a boiling caustic soda aqueous solution with a concentration of 60 g/Q, and the reduction rate of the core polyester component was brought to a predetermined value by adjusting the immersion time. did. Subsequently, acid dye (“NylomineBlue A-G”), 1
%owf, after dyeing at 98℃, finishing setting at 180℃, dyed fabric made of hollow composite fibers'! I built A.

The properties of the obtained fabric were measured and the results are shown in Table 1. In addition, 5 of the fibers constituting the fabric No. 2
00x microscopic photograph.

As shown in FIG. 1, it was observed that a clear hollow space existed between the core and the sheath.

Occurrence of sheath tearing of hollow composite fibers: Comparative evaluation was made using microscopic photographs of the cross sections of the fibers constituting the test fabrics.

Fabric tension and waist: Relative evaluation based on tactile sensation.

It also showed excellent dyeing properties comparable to commercially available polyamide fibers. Next, a slip for women was manufactured using this dyed fabric. It drapes well along the body line, and despite being thin and light, it has excellent heat retention.

As can be seen from the results in Table 1, in order to produce lightweight fabrics with high heat retention, it is necessary to adjust the composite ratio and hollowness ratio of the hollow composite fibers constituting the fabrics to appropriate levels. It was effective in imparting various properties (tension, elasticity, tear strength, etc.) necessary for use in fabrics.

In addition, for comparison, the results of a knitted fabric with a half structure obtained in the same manner as above using a polyamide filament yarn of 40 denier, 12 filaments made of polyε-capramide obtained by spinning and drawing in a conventional method. Also shown in Table 1. This tricot fabric made of polyamide single fiber had a low CLO value and poor heat retention.

Long-sleeved, zero-neck shirts were sewn from fabrics No. 4 (invention) and No. 10 (comparative example), and a wearing test was conducted by eight female panelists in an artificial climate room. During the wear test, the wearer wore the long-sleeved zero-neck shirt as the inner layer and the 100% polyester long-sleeve araus as the outer layer, and was kept at rest for 30 minutes in an indoor environment of 15° C. and 65% RH.

Then, changes in skin temperature were investigated using a temperature sensor attached to the human chest, and the results are shown in Figure 4. Also,
Table 2 shows how the panelists felt when wearing the product.

As can be seen from the results in Table 2 and Figure 4, the fabric (N
O,4) has lower skin temperature at rest than conventional fabric (N
o, 10>, it was demonstrated that the clothing has excellent heat retention.

In addition, the fabric of the present invention was excellent both immediately after wearing and at rest, and was excellent as a heat-retaining fabric for clothing. On the other hand, with conventional fabrics, the poor heat retaining properties both immediately after wearing and while at rest are evident in the feeling of wearing, and the wearer feels uncomfortable.

Example 2 When spinning a core-sheath type composite fiber with a composite ratio of sheath and core of 30/70 in the same manner as in Example 1, the yarn fineness was varied by changing the amount of polymer discharged, etc. Different core-sheath type composite lia fibers were produced. And, similar to Example 1,
After forming a knitted fabric with a 32-gauge half structure, weight reduction treatment was performed with a caustic soda aqueous solution to produce a fabric made of hollow composite fibers.

The obtained fabric was evaluated in the same manner as in Example 1, and the results are shown in Table 3.

As can be seen from the results in Table 3, setting the yarn fineness at the raw yarn stage to 70 denier or less was effective in producing a lightweight fabric with high heat retention.

[Effect of the invention] The lightweight fabric according to the present invention has a basis weight of 40 to 100 g/Tr12 and a thickness of 0.25 to 0.35 mm, and has a CLO value even though it is thin and light like a feather. 0.
It has a high heat retention property of 65 or higher, comparable to wool. Furthermore, since the surface is made of polyamide, it has excellent dyeability, durability, surface feel, etc., and can be used in the same way as conventional polyamide fiber fabrics. Moreover, since the polyester layer is present in the core, it has excellent dimensional stability and wrinkle resistance, and has appropriate tension and stiffness.

Because of these characteristics, the lightweight fabric according to the present invention is useful for innerwear products, especially women's innerwear products such as lingerie, foundation, new innerwear, and sports innerwear, but it also has high heat retention and It can also be used for fabric products that are required to be lightweight, such as outerwear and sportswear.

In addition, this lightweight fabric has an appropriate composite ratio of yarn,
In addition, it can be easily produced industrially by heating and alkali-treating the fabric after it is made into a fabric.

[Brief explanation of the drawing]

FIG. 2 is a fiber cross-sectional view illustrating a composite form in an empty composite fiber. FIG. 3 is a diagram showing the proportions of the sheath portion, core portion, and hollow portion of the hollow composite fiber specified in claim 2. FIG. 4 is a diagram showing changes in skin temperature when evaluating the wearing of clothing using the fabric according to the present invention or a conventional fabric. [Explanation of symbols] 1: Sheath part (polyamide layer) 2: Core part (polyester layer) 3: Hollow part

Claims (4)

[Claims] (1) A fabric composed of a core-sheath type hollow composite fiber having a sheath made of polyamide, a core made of polyester, and a hollow part existing between the sheath and the core, and The basis weight (Wg/m^2) and thickness (A
mm) and CLO value (C) are 40≦W≦100, 0
．． A lightweight fabric with excellent heat retention, characterized by simultaneously satisfying 25≦A≦0.35c≧0.65. (2) The ratio of the sheath part, the core part, and the hollow part in the fiber cross section of the core-sheath type hollow composite fiber (each x
%, y%, z%) simultaneously satisfy 25≦x≦70, 10≦y≦65 and 10≦z≦60. (3) The lightweight fabric with excellent heat retention properties according to claim 1, wherein the fabric is used for inner wear. (4) Composite ratio (wt%) of the sheath made of polyamide and the core made of polyester is 25/75 to 70/30
The lightweight fabric according to claim 1 is produced by forming a fabric with filament yarns consisting at least of polyester polyamide core-sheath type composite fibers, and then treating the fabric with a heated alkaline aqueous solution. A method for producing lightweight fabric with excellent properties.