JPS6257982A - Production of fabric excellent in opacity - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a filament A product that is transparent and has excellent texture. More specifically, the present invention relates to a fabric that contains filaments with a special cross-sectional shape at a certain ratio or more, and which has excellent opacity without impairing the texture effect by appropriately arranging the filaments with a special cross-section within the fabric. be.

(Prior Art) Filament-like fabrics made of synthetic fibers have been particularly developed for use in recent years, and are widely used in everything from thin fabrics such as blouses to thick clothing such as slacks and coats. these are,
This progress has been made as a result of improvements such as two-color texture, drapability, etc., while taking advantage of the easy care properties of synthetic fibers.
In particular, the aim is to make fabrics lighter and thinner, taking full advantage of the characteristics of synthetic fibers. However, the direction of lightweight "f!J" material also promotes the "transparency" of fiber knitted fabrics, so that when wearing sewn products, items worn underneath may be visible. There have been many cases where aesthetics are impaired.

Conventionally, synthetic filament woven and knitted fabrics have the same texture and same basis weight as natural fiber M-knitted fabrics such as cotton and silk, and are easier to see through, and synthetic filament A-knitted fabrics have not been used in fields where opacity is required. It was generally difficult. However, in fields where durability and functionality are strongly required, such as white or light-colored lab coats and sports clothing, synthetic filament fabrics are becoming more popular due to increasing consumer needs for switching from natural fibers to synthetic filament fabrics. Research into opacity is progressing, and a few technologies have already been developed.

One is the one in which inorganic fine powder such as titanium dioxide is dispersed in a resin binder and coated on the fabric surface, or the fiber surface is formed with a resin envelop with a different refractive index. Examples include those that have unevenness formed thereon. However, because of the applied resin layer, these have the disadvantage that the texture becomes rough and hard, the inorganic powder or coating falls off due to friction, and the effectiveness tends to decrease due to surface smoothing, so they are not widely accepted by consumers. It's not something you can do.

In addition, a technology using a sea-island composite fiber made of two types of components with different average refractive indexes has been published to make the fiber itself opaque (Japanese Patent Publication No. 46-8814).
. Although this method does not have the disadvantages of the post-processing method described above, it imposes certain restrictions on the components used, requires unnecessarily complicated manufacturing equipment because it is difficult to suppress the influence of light reflected on the fiber surface, and is not economical. It is hard to say that it is a practical method.

In addition, a proposal was made to make a core-sheath type composite fiber and contain a large amount of titanium oxide in the core part.
is being done. However, this fiber itself
Even though it is opaque, when it is made into a woven or knitted fabric, it cannot cover the gaps in the structure, so it is not opaque as a woven or knitted fabric.

(Problems to be Solved by the Invention) In view of this situation, the present inventors have devised the design of the raw material and the weaving processing stage, regardless of the post-processing method, so as not to impair the original texture and characteristics of the fiber. The present invention was arrived at as a result of intensive research aimed at obtaining synthetic filament fabrics with permanent opacity comparable to natural fiber fabrics using an industrially advantageous method.

(Means for Solving the Problems) The method of the present invention is characterized in that A
, a composite consisting of a fiber-forming synthetic linear polymer of the B2 component, which can form fibrillated filaments of the A component with an oblateness of 1.4 or more and a fineness of 0.05 to 5 deniers when only the B component is dissolved and removed with a solvent. When processing a woven fabric using a multifilament containing at least 80% filament in fineness ratio as component A with a small number of warps and/or wefts (both 50 inches), component B is dissolved and removed by treatment with a solvent of component B. After that, mechanical and physical tension/relaxation or compression is applied, and in the cross section of the fabric, the angle between the cross-sectional long axis of the fibrillated flat filament (composed of component A) and the fabric surface is 4
The flat filaments arranged at less than 50 cm occupy at least 50 cm of the entire flat filament, and have a basis weight of 400
It is characterized by having a light transmittance index that satisfies the following formula, with a thickness of y/rd or less and a thickness of 0.8 or less.

D×T≦6 (however, D double weight (gl/door), T: light transmission index) The method of the present invention will be explained in detail below.

The composite filament used in the method of the present invention consists of a fine component (component A) arranged continuously in the fiber axis direction and another component (component B).
component) to form one filament, and A
Component and B component exhibit different solubility in the solvent. As the A and B components constituting the composite filament, fiber-forming synthetic linear polymers such as polyamides, polyesters, polyolefins, polyurethanes, and copolymers thereof are suitably applied as the A component, or polyamides or polyesters are preferably used. It is preferable that there be. Polyesters mentioned here include polyethylene terephthalate, polyethylene isophthalate, copolymerized polyethylene terephthalate, polybutylene terephthalate, etc. Polyamides include aliphatic polyamides such as nylon 6, nylon 66, and nylon 610, and polyxylylene adipers. Examples thereof include aromatic polyamides such as polyamide, polyhexamethylene talamide, and the like. The fiber-forming synthetic linear polymer used as component A may also contain various additives, particularly inorganic and organic powders such as matting agents, pigments, lubricants, crystal nucleating agents, and catalysts. In addition to the above-mentioned polymers having different properties from those of component A, component B may be any fiber-forming polymer that has the ability to coalesce filaments. For example, there are many combinations of A and B components, such as nylon 6 and polyethylene terephthalate, nylon 6 and polystyrene, polyethylene terephthalate and polystyrene, etc., but B
It is preferable to use polyethylene glycol copolymerized polyethylene terephthalate and/or 5-sodieme sulfonate isophthalic acid copolymerized polyethylene terephthalate as the components.

Any solvent may be used as long as it dissolves only the B component or has a higher solubility for the B component than the A component as the solvent used to remove the B component of the composite filament made of the A and B components as described above. However, for example, in the case of a combination of nylon 6 and polyethylene glycol copolymerized polyethylene terephthalate, about 1 liter of sodium hydroxide aqueous solution,
Examples of combinations of polyethylene terephthalate and polystyrene include trichlorethylene and the like.

When component B is dissolved and removed from such a composite filament with a solvent, a fibrillated filament made of component A has an oblateness of 1.4 or more and a fineness of 0.05 to 5 deniers. Here, the flat filament will be explained. Fiber oblateness generally refers to the length of the major axis (L) and the length of the minor axis (J?) in the cross section of the fiber. ) is the ratio (L/J).

As shown in FIG. 2(a), objects that are determined to be flat at first glance are shown in the figure, and may be expressed by the numerical value of l.

However, if the ribbon-like object is curved, has a polygonal shape with approximately four sides or less, or a polygonal shape with less than four corners, the longest length when projected is determined as shown in Figure 2 (b) and (c). The new shortest length is defined as l.

The flattened filament used in the present invention needs to have an oblateness of 1.4 or more as defined above. This is to increase the reflection of light on the flat surface, and if the reflection of light is large, the light that enters into the fabric will naturally be suppressed, and furthermore, as the fibers repeat the reflection between each other within the fabric, it will naturally attenuate and go out of the fabric. The amount of light leaking can be reduced to a level that does not cause any problems. If the oblateness is less than 1.4, the oblateness is comparable to that of a triangular cross-section yarn obtained by ordinary spinning or a round cross-sectional yarn deformed by high-temperature false twisting, and only the opacity of the fabric obtained by conventional techniques can be obtained. , 1.4 or higher is required.

In order to further improve the effect, the aspect ratio is preferably 1.6 or more, and it is more desirable that the fiber cross section has at least one straight, smooth side, preferably two sides. However, even if the edges are not smooth and have increased unevenness due to false twisting,
If the l and flatness are large enough, the objective can be achieved.

The forms of composite filaments to obtain fibrillated filaments with such oblateness are shown in Figures 8 (a) to (f).
This is possible by using the following form.

Furthermore, it is effective to perform false twisting to increase the coverage and improve the texture by crimp. False-twisting methods are broadly classified into spindle false-twisting methods and friction false-twisting methods, but belt-type or disk-type friction false-twisting methods are suitable for the purpose of the present invention. This is because the cross-sectional deformation given to the false-twisted yarn by mechanical and thermal forces during false-twisting is smaller in the friction false-twisting method.
This is because it is easy to maintain the designed and spun shape for the purpose of the present invention during composite filament spinning.

The fineness of the flattened fibrillated filament of A component obtained by dissolving and removing component B of a composite filament consisting of two components A and B is preferably in the range of 0.05 to 5 deniers, more preferably 0.2 to 2 deniers. It is .5 denier.

If it is less than 0.05 denier, it is undesirable because it is so small that it deteriorates the wrinkle resistance of the fabric, or when mixed with other filaments, it gets buried between those filaments. On the other hand, if it exceeds 5 denier, the texture becomes rough and hard, which is not preferable. Considering aspects such as spinnability, ease of handling the yarn, and texture of the fabric, it is 0.2 to 2.5.
A range of denier is more preferable.

In the method of the present invention, when weaving, the composite filament may be used in the most appropriate form, taking into consideration the structure, finishing agent, etc. For example, when the fabric structure has a single layer structure such as plain weave or twill weave, the effect can be very good if only the filament is used for the warp and weft, but if it is used as a mixed yarn by double twisting with ordinary yarn, The purpose can also be achieved by interweaving with ordinary yarn. Furthermore, in the case of a multilayer structure such as a double weave, it is not necessary to use only the filament.
A sufficient effect can be achieved just by using it as the constituent threads on the front or back side. Similarly, it is also effective to interweave with ordinary yarn on the front or back weave, and it is also possible to use two mixed fibers twisted together with ordinary yarn in advance.

However, in the present invention, when weaving, a multifilament containing at least 30 fibers of the composite filament as component A must be used for at least 50% of the warp and/or weft. This is to create a concealing effect by uniformly arranging the flat surfaces on the surface of the fabric. After weaving using the multifilament, when only the B component is dissolved or when the B component is dissolved and removed by treatment with a solvent that has higher solubility for the B component than the A component, the If the blending ratio of the flat fibrillated filaments of component A in the multifilament is less than 80% in terms of fineness ratio, the concealing effect of the multifilament itself will decrease; Even if the content is 80% or more, if the multifilament is used in less than 50% of the warp and/or weft, the opaque effect of the fabric will be reduced. In general, warp yarns have a higher implant density than weft yarns and contribute more to opacity, and it is also easier to obtain dimensional stability with warp yarns, making it easier to stabilize forms such as crimp within the fabric. For this reason, it is effective to use a multifilament containing the flat fibrillated filaments in the warp.

In the opaque fabric produced by the method of the present invention, the flat filaments, which are arranged such that the angle between the cross-sectional long axis of the flat filament made of component A and the fabric surface is less than 45 in the cross section of the fabric, are at least 50% of the flat filament group. They must be made to occupy as much of the country as possible. If it is less than 50 inches, the opacity effect of the fabric will be reduced.

As a method for achieving such a specific arrangement, the warp of the fabric and/or
Alternatively, tension/relaxation is applied multiple times in the weft direction, and pressing/relaxation is applied multiple times in the thickness direction of the fabric. Spiral brakes, camfits, sanphorizes, etc. are effective for tensioning and relaxing fabrics in the warp and/or weft directions, and shimmy calenders, shimmy calenders, etc. are effective for applying pressure in the thickness direction.
A cold calendar etc. is effective.

In addition, for processing, anti-static finishing agents and water-repellent finishing agents are used.

It is permissible to use an oleophobic finish. There is no problem in coating with resin liquid such as urethane or acrylic. A urethane-based or fluorine-based resin film may be laminated.

The opaque fabric obtained by the present invention has a basis weight of 400!
/lri or less, thickness 0.8 fl or less. Eye weight is 4
If it exceeds 00 y/rrl, the clothing becomes too heavy and wearability is inhibited. Moreover, if the thickness exceeds 0.8, it becomes a thick fabric and impairs the activity when worn, which is not preferable. Compared to ordinary synthetic filament fabrics, the opacity of the fabrics obtained by the present invention is 800? /- or less, thickness 0.
This is particularly noticeable when the distance is 65 m or less.

The light transmission index of the fabric thus obtained is measured by the following method.

Generally, Pineo's equation is useful for the optical density of light transmitted through dyed fabrics. Function F regarding spectral reflectance R
is known as a function related to the ratio K/S+c of the absorption coefficient and the scattering coefficient S, and is expressed by the following equation.

The R-chi of the dyed cloth can be measured using a self-recording spectrophotometer equipped with an R-cam, and the /S of the sample cloth can be determined using a conversion table.

The opacity (hiding degree) of the sample is determined by calculating the R% of the sample cloth at a wavelength of 500 nm, obtaining the K/S value, and calculating Δ using the following formula.
(K/S) is calculated and expressed as a light transmission index T.

T=Δ(K/S)=(K/S)B−(K/S)w
Here, (K/S)B and (K/S)W are the wavelengths of the cloth surface when the black mount and white mount are applied to the back of the sample, respectively, 600n.
Represents /S in m. Therefore, the smaller the T value, the higher the opacity.

Generally, the light transmittance of textiles decreases as the basis weight increases. The light transmission index determined by the above measurement method is T, and the basis weight is D (P/m
'), the relationship of TXD)8 is obtained for conventional filament ha products for general clothing, whereas in the case of the fabric according to the present invention, the range showing opacity is TXD≦
It is necessary to have a relationship of 6. In order to keep it within such a specific range, conditions such as weaving density during weaving, presence or absence of twisting, presence or absence of glue, width adjustment during processing, suppression, false twisting conditions, etc. It is necessary to choose appropriately. If opacity is particularly required, the range is TXD≦5, in the most severe case TXD≦4.

(Effects of the Invention) The woven fabric according to the present invention has extremely good opacity, and the opacity remains the same after 30 washes as before washing.

Also, it is easy to wear. The woven fabric of the present invention is particularly suitable for women's clothing such as thin blouses, dresses, skirts, and slacks.

Example 1 Nylon 6 full-dull polymer was used as the A component, and polyethylene glycol with a molecular fi of 4000 was used as the B component.
Figure 3 (d), (e
) and (g) were obtained, each having a cross-sectional shape of 100d/48f. Using these yarns for 100% warp and weft, plain weave 3
I made a bowl. Each of the obtained fabrics was immersed in a 1% aqueous sodium hydroxide solution at 98°C for 80 minutes to dissolve and remove the polyethylene glycol copolymerized polyethylene terephthalate (component B), and then loosen the fabric with a spiral brake in the warp and weft directions. After applying tension and relaxation to the fabric, it was passed through a shimly calender three times and then dry-heated at 170"C. The physical properties of the fabric obtained are shown in Table 1. In addition, the cross section of the fabric was examined using an electron microscope. The angle between the long axis of the flat filament and the surface of the fabric was observed, and the proportion of the flat filament having an angle of less than 45 was calculated.
, -5, -5 or below: Margin From this, the flatness of the flat fibrillated filament is 1
．． It can be seen that it is 4 or more, preferably 1.6 or more.

Example 2 A laminated composite yarn having a cross section as shown in FIG. 3(a) or (b) was prepared using 6 nylon furdal as the component A and polyethylene glycol copolymerized polyethylene terephthalate as the component B. The components A and B were joined in a dorsal-ventral structure at a volume ratio of 8=1 in a die, and then divided repeatedly using a static mixer in the die. At this time, by changing the number of static mixers in the cap,
Seven types of composite yarns were obtained by changing the number of division stages and the number of die holes. All composite yarns had a total fineness of 100 d.

These composite yarns were false-twisted at a temperature of 195°C.

After false twisting in the S direction using a disk type false twisting machine at a twist number of 2600 T/M, double yarn combination twisting was performed in the S direction at 150 T/M. False twisted yarn 150/48 of polyethylene terephthalate semidull filament, which usually has a round cross section, was used as the warp yarn, and the false twisted yarn of the composite filament described above was placed as the weft yarn to form a plain weave. The obtained fabric was treated in the same manner as in Example 1, and its physical properties are shown in Table 2.

-・The fineness of the fibrillated flat filaments as component A after dissolving and removing component B is such that if the flatness is 1.4 or more, the opacity is good, but if it exceeds 5 deniers, the texture of the fabric becomes hard, and When it was smaller than 0.05, wrinkles were likely to occur.

Example 3 Component A is nylon 6 full-dull polymer.

As component B, polyethylene terephthalate copolymerized with 5 moles of 5-sodium sulfonate isophthalic acid was used at a volume fit ratio of A:B = 3:1, as shown in Figure 8(e).
A composite filament 50d/24f having a cross-sectional shape of 50d/24f was obtained.

The composite filament and a regular round cross-section nylon 6 semi-dual filament of 50 d/l 2 f were combined at an appropriate ratio to form a multifilament with a total fineness of 300 denier, which was then implanted as a weft. At this time, as the warp thread, ordinary round section nylon 6 full dull filament 70d
/18f was used to form a plain weave. Example 1 of these fabrics
processed in the same way. Table 8 shows the physical properties of the obtained fabric.

It was found that in the multifilament containing flat filaments used, good opacity could not be obtained if the flat filament ratio of component A was less than 80 inches.

Example 4 After the composite filament 100 d/48 f having the cross-sectional shape of FIG. 8(d) obtained in Example 1 was false-twisted in the S direction at a temperature of 185°C and a twist number of 2800 T/M using a disk type false-twisting machine. , S-direction 150T/M twin yarn plying and twisting.

When warping this thread into warp threads, usually round-section nylon 6
The composite filament was appropriately arranged in the warp of the false twisted twin-ply twisted yarn of Fuldal filament 70d/24f, and the ratio of use in the warp was varied.

As the weft, we usually use a round cross-section nylon 6 semi-dull filament of 70 d/24 f false twisted twin yarn and 2/2
Made of twill weave. The resulting fabric was treated in the same manner as in Example 1. The results are shown in Table 4.

From this, it is necessary to use 50 cf3 or more of composite filaments in the warp.

Example 5 The composite filament 100 d/48 f having the cross-sectional shape shown in FIG. 3(e) obtained in Example 1 was false-twisted in the S direction at a temperature of 185°C and a number of twists of 2800 T/M using a disk type false-twisting machine.
1507/M twin yarns were twisted in the S direction.

A 2/2 twill yarn was made using this yarn for warp and weft. The obtained fabric was immersed in an aqueous solution of I-IJ hydroxide for 80 minutes, and then tensioned and relaxed in the warp and weft of the fabric using a spiral brake. Next, pass through the stain IJ-calendar 17
The sample was heat set at 0°C, but the number of times the sample was passed through the Simily calender was varied. The results are shown in Table 5.

Table 5

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a fabric obtained by the method of the present invention. FIGS. 2(a), 2(b), and 2(c) illustrate how to measure the major axis and minor axis l used in the formula for the flatness of a flat filament in the method of the present invention. FIGS. 8(a) to (f) are cross-sectional forms of composite filaments that can be used in the method of the present invention, and FIG.
Kanebo Go 1 (4 years old)
(b) (c) (d) (e) (now) (sweat) Procedural amendment (method) % formula %: 2. Title of invention Method for producing textiles with excellent opacity 8. Cases of persons making amendments Relationship Representative Patent Applicant Address 5-17-4 Sumida, Sumida-ku, Tokyo 5-90 Tomobuchi-cho, Bejima-ku, Osaka 534 Kanebo Co., Ltd. Patent Department Telephone: (06) 921-1251 6. Amendments Contents (1) “Second line” written in the 9th line from the bottom of page 28 of the specification
Figures (a) (b) (C') Correct J to "Figure 2 J."

Claims (1)

[Scope of Claims] (1) Consisting of a fiber-forming synthetic linear polymer of two components A and B having different solubility in solvents, when only component B is dissolved and removed with a solvent, the oblateness is 1.4 or more; Fineness 0.05~
When processing a woven fabric in which at least 50% of the warp and/or weft is a multifilament containing at least 30% of composite filaments capable of forming fibrillated filaments of A component of 5 denier in terms of fineness ratio as A component, B After treating with a component solvent to dissolve and remove component B,
Mechanical or physical tension/relaxation or pressure is applied, and in the cross section of the fabric, the long axis of the fibrillated flat filament made of component A and the fabric surface are arranged at an angle of less than 45°. The filament accounts for at least 50% of the total flat filament, and has a basis weight of 400 g/m^
A method for producing a woven fabric with excellent opacity, characterized by having a light transmittance index of 2 or less and a thickness of 0.8 mm or less that satisfies the following formula. D×T≦6 (however, D: area weight (g/m^2), T: light transmission index) (2
2.) The method according to claim 1, wherein the composite filament has a cross section in which component B is joined without completely surrounding component A. (3) The method according to claim 2, wherein the composite filament has a cross section in which two components are repeatedly joined side-by-side. (4) The method according to claim 2, wherein the composite filament has a hollow portion formed by repeatedly joining two components side-by-side. (5) The method according to claim 2, wherein the composite filament has a cross section in which a B component having a radial shape and an A component having a shape that complements the radiating portion are joined. (6) The method according to claim 1, wherein the flat filament is polyester or polyamide. (7) Multifilament including composite filament is
The method according to claim 1, wherein the yarn is a false twisted yarn. (8) Multifilament including composite filament is
The method according to claim 1, which is subjected to friction false twisting.