JPH09119070A - Fabric capable of preventing discoloration - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a fabric, prevented from discoloration due to water such as rain or perspiration and useful for clothes or daily necessaries and sundries by forming a film of a resin having a refractive index within a specific range on the surface of a fabric containing the specified core-sheath type conjugated synthetic fibers. SOLUTION: This fabric is obtained by forming a fabric from core-sheath type conjugated fibers having a polyester, containing >=3wt.% and <=30wt.%, preferably >=5wt.% and <=10wt.% white pigment such as titanium oxide arranged in a core part and a cation-dyeable polyester containing <=2wt.% white pigment same as described above in a sheath part or the conjugated fibers and other fibers, then immersing the resultant fabric in a treating bath of a resin, consisting essentially of an acrylic-urethane latex and a modified silicone and having 1.3-1.5 refractive index, squeezing the fabric with a mangle, drying the fabric with a tenter, heat-treating the dried fabric at >=150 deg.C, fixing the resin on the fabric and forming an outer film having 0.01-100μm thickness and 0.1-10% owf pickup. Thereby, fabric is prevented from discoloring with water.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cloth having a discoloration preventive property against water not only for clothing such as blouses, sports shirts and raincoats but also for daily sundries such as umbrellas and bags. is there.

[0002]

2. Description of the Related Art When wet or sweaty, clothes such as shoulders, armpits and back are discolored only when wet, which may cause discomfort. Also, bags made of synthetic fibers, etc., were significantly discolored when wet with rain, etc., and were unpleasant in appearance. Conventionally, a core-sheath type composite fiber containing a large amount of white pigment in its core is known as a fiber that is difficult to penetrate even when wet (for example, Japanese Utility Model Laid-Open No. 6-37380, Japanese Patent Application Laid-Open No. 5-93343, etc.). . However, since this fiber has a large white light reflection due to the white pigment itself, the contribution of the decrease in the ratio of white light caused by the decrease in the refractive index due to water is small, and although it has the effect of making it difficult to see through even when wet, such a core-sheath Even type composite fibers have the drawback of discoloring when wet.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a cloth having a property of preventing discoloration by water.

[0004]

Hereinafter, the present invention will be described in detail. First, the reason why the color of fiber generally changes when it gets wet will be explained. When a human looks at an object, his eyes capture the combined light of the surface reflected light reflected by the surface of the object and the internally reflected light that enters the object and is reflected at the internal boundary surface. The surface reflected light is white light containing light of all the same wavelengths as the incident light, and the internally reflected light is colored light that has been absorbed by a dye at a specific wavelength. here,
It is known that the larger the proportion of white light, the more whitish, and the smaller the proportion of white light, the deeper the color. Water has a smaller refractive index (n = 1.33) than fibers, but when the fibers get wet, the surface of the fibers becomes covered with water and the refractive index becomes lower,
The surface reflectance becomes small. Therefore, it becomes discolored when wet with water.

As a result of intensive studies by the present inventors, a sufficient discoloration preventing effect is obtained when a film is formed on the surface of the core-sheath type composite fiber with a resin having a refractive index smaller than that of the fiber and close to that of water. The present invention has been discovered, and the present invention has been achieved. Hereinafter, the yarn used in the present invention will be described in detail. Synthetic fibers are suitable for the core-sheath type composite fibers used in the fabric of the present invention. For example, polyester, polyamide,
Fibers manufactured by melt spinning, such as polypropylene, are desirable in the manufacturing process.

There are two main reasons for using a core-sheath type composite fiber instead of a single component fiber containing a large amount of white pigment. One is that fibers having a large white pigment content, particularly fibers having a white pigment content of 3% by weight or more, may wear guides and the like in the weaving and weaving process and cause defects such as fluff and streaks. Therefore, when a large amount of white pigment is added, it is better to cover with a sheath portion having a smaller content of white pigment because of better processability. Second, fibers with a high white pigment content are generally inferior in color development. However, when it is covered with a sheath having a small white content, it is possible to prevent the deterioration of the color developability.

It is necessary for the white pigment of the core portion to have sufficient opacity, and even if it is dyed in a color other than white, there is no problem of deterioration in color developability and it does not hinder the production of the raw yarn. For example, metal oxides such as titanium oxide, zinc oxide, magnesium oxide, and calcium carbonate are desirable. Considering the cost, titanium oxide is most suitable. The amount of this white pigment added must be 3% by weight or more and 30% by weight or less.
It is desirable that the content is not less than 10% by weight and not more than 10% by weight. When the amount of white pigment in the core exceeds 30% by weight, the strength and elongation are significantly reduced,
Disables raw yarn manufacturing and knitting and weaving processes. Also, 3
If it is less than wt%, the discoloration preventing effect of the present invention cannot be obtained.

On the other hand, the white pigment in the sheath portion must be contained in an amount of 2% by weight or less. This is because the coloring property is deteriorated by more than 2% by weight. Moreover, the base polymer may not be the same for the core portion and the sheath portion. For example, in the case of a polyester core-sheath composite fiber, only the sheath portion may be a cationic dyeable polymer. In the case of a core-sheath composite fiber of polyamide, the core may be nylon 66 and the sheath may be nylon 6.

The core component and the sheath component may be compounded concentrically or eccentrically. The weight ratio of the core and sheath is preferably in the range of 1/3 to 3/1, particularly preferably 1/2 to 2/1. If it is less than 1/3, the effect of preventing discoloration becomes small, and if it exceeds 3/1, it may be difficult to cover the core component with the sheath component during spinning. The fabric form of the present invention may be a woven fabric or a knitted fabric.
The ratio of the core-sheath type composite fiber to the fabric is 100.
% Is optimal, but other materials may be mixed in the range of 70% or less, preferably 50% or less. For example, regarding textiles, core-sheath type composite fibers and monocomponent yarns (for example, polyester, polyamide, cupra, rayon, etc.), warp-one alternating weave, weft-one alternating weave, warp-one alternating weave, plain weave, twill weave, satin It may be a cloth composed of other fibers such as various kinds of woven fabrics. However, in this case, the higher the proportion of the core-sheath type composite fiber, the more effective the prevention of discoloration. Regarding the knitted fabric, the front and back sides are integrated and the front and back sides are integrated, and the front and back sides are knitted with core-sheath type composite fibers and at least a part of the back side is knitted with a single component yarn A double-layered knitted fabric such as a double face or a double face may be used. For example, when a knitted fabric composed of polyester core-sheath type composite fibers on the front side and cupra on the back side is subjected to low refractive index resin processing, it not only prevents discoloration due to water but also imparts sweat absorption by the back side. You can
A more comfortable cloth for clothing can be provided. Similarly, this effect can be seen in a core-sheath structured yarn on the front side, a polyester on the second layer, and a three-layer knitted fabric composed of rayon on the back.

Next, the resin film formed on the fabric of the present invention
The refractive index will be described. The refractive index mentioned here is absolute
Refractive index, which is the speed of light in a vacuum and the phase of light in a medium
It is the ratio to the speed v. That is, if the refractive index is n, then
The relationship between c and v is as follows. n = c / v The resin film used in the present invention has a refractive index of fiber
It should be smaller and closer to water. Specifically, 1.
It is preferably 3 or more and 1.5 or less. Have a refractive index of less than 1.3
No resin film actually exists. Further, the refractive index of the resin film is 1.
If it exceeds 5, the difference in refractive index with water will widen and the effect of discoloration prevention will be increased.
The fruit does not appear. Where the refractive index of the fiber is n ₁, Of resin film
Refractive index n_TwoThen, n₁, N_TwoKeeps the following relationship
It is desirable.

0.05 <(n ₁ −n ₂ ) (however, 1.3 <n ₂ <n ₁ <1.7) These resin coatings include, for example, modified silicon, fluorine compounds, fluorine compounds and hydrophilic compounds. Examples of the resin having a low refractive index include a mixture of a polymerizable vinyl monomer and a mixture of a fluorine compound and a water-soluble polyamide resin. Specifically, "Schwat" (trade name, manufactured by Kao Corporation), which is a deep-color processing agent mainly composed of acrylic-urethane latex and modified silicon,
AFH, a softening agent for various fibers whose main component is modified silicone
-102 (manufactured by Senka Co., Ltd.) and the like. It is also possible to add an antistatic agent, a dispersant, a stabilizer and the like to these resin main components.

[0012] The resin film formation is pad-dry-cure.
It is desirable to carry out. For example, soak the dough in resin, squeeze it with a mangle, and then dry it with a tenter (100 ~
130 ° C.), and further 150 ° C. or more, can be formed by a step of fixing the resin to the cloth. And as a preferable condition of the film for sufficiently obtaining the effect of preventing discoloration, it is required to be uniform on the fiber surface, and the thickness is 0.01 to 10
The thickness is 0 μm, is adhered to the surface of the fabric as continuously as possible, and the adhered amount is 0.1 to 10% owf with respect to the fiber weight.

[0013]

EXAMPLES The present invention will be described specifically with reference to Examples.
The present invention is not limited to these. Example 1
2. Dyes used in Comparative Examples 1 to 3, dyeing conditions, and resin processing conditions are as follows.

In the following (3) Resin processing method,% owf indicates the ratio to the weight of the fiber, and part to the total amount of the resin processing liquid. (1) Dye Kayacryl Blue GSL-ED (manufactured by Nippon Kayaku Co., Ltd.) 0.1% owf Kayacrl Blue GSL-ED (manufactured by Nippon Kayaku Co., Ltd.) 0.1% owf Kayacryl Blue GSL-ED (manufactured by Japan) Yaku Co., Ltd. 0.1% owf Mikawhite KTN (Mitsubishi Chemical Co., Ltd.) 1.0% owf (2) Dyeing conditions Bath ratio 1:20 Temperature * hour Cationic dyeable yarn 95 ° C. * 60 minutes Core sheath Type composite fiber yarn 120 ° C. * 60 minutes pH 5 buffer solution (CH ₃ COOH, CH ₃ COONa) (3) Resin processing method Resin processing method of Example 1 and Comparative Example 3 One-step processing (pad) “Schwat A-10” ( Trade name, high molecular weight carboxylic acid resin) 10.0% owf "Schwat N-2" (trade name, glyoxal cross-linking agent) 0.01% owf (dry) 130 * 4min Two-stage processing (pad) "Schwat N-2" (trade name, glyoxal crosslinker) 4.0% owf "Schwat TR-440" (trade name, acrylic-urethane latex + modified silicone) 0.2% owf Antistatic agent “TA-267” 0.5% owf (dry) 120 ° C. * 4 min (cure) 180 ° C. * 1 min The above resins are all manufactured by Kao Corporation.

Resin processing method of Example 2 (pad) “Bondic H-6030” (trade name, polyurethane resin) 15.0 parts “Dick Silicon Softener A900” (trade name, silicone softener) 1.5 parts "FINETEX U-31" (trade name, blocked isocyanate) 5.0 parts Water 78.5 parts (squeeze ratio) 50% (dry) 130 ° C * 3min (cure) 150 ° C * 3min In addition, all of the above resins Made by Dainippon Ink Co., Ltd.

Resin processing method of Comparative Example 3 Resin containing water-based urethane as a main component (pad) “Bondic 1850NS” (Brand name, polyurethane resin) 15.0 parts “Dick Silicon Softener A900” (Brand name, silicone-based flexible) Agent) 1.5 parts "FINETEX U-31" (trade name, blocked isocyanate) 5.0 parts Water 78.5 parts (squeeze ratio) 50% (dry) 130 ° C * 3min (cure) 150 ° C * 3min All of the above resins are manufactured by Dainippon Ink Co., Ltd.

[0017]

Example 1 A core-sheath composite having a core-sheath weight ratio of 1/1, which is made of a cationic dyeable yarn of a polyester containing 8% by weight of titanium oxide as a core component and a polyester containing no titanium oxide as a sheath component. After dyeing 2way tricot using fiber (refractive index 1.65) and spandex with blue, red, yellow and fluor white, low refractive index resin (refractive index 1.45) processed (resin adhesion amount: 4% owf (relative to fiber), film thickness: about 0.
1 μm). Then, the magnitude of discoloration due to water was examined by calculating a color difference ΔE ^* with a colorimeter Macbeth Color Eye 3000 manufactured by Sakata Inx Co., Ltd. Color difference is perceived chromaticity index a ^* , b
It is a value calculated by substituting each difference between two samples using the ^* and the lightness L ^* as in the following formula.

ΔE ^* = {(ΔL ^* ) ² + (a ^* ) ² +
(B ^* ) ² } ^1/2 As a result, the color difference between dry and wet is shown in Table 1. Sensually, the greater the color difference between dry and wet, the more discomfort

[0019]

Comparative Example 1 A core-sheath composite having a core-sheath weight ratio of 1/1, which is made of a cationic dyeable yarn of a polyester containing 8% by weight of titanium oxide as a core component and a polyester containing no titanium oxide as a sheath component. After dyeing a 2-way tricot using fibers and spandex, the magnitude of the discoloration was examined. as a result,
The color difference between dry and wet is shown in Table 1.

[0020]

Example 2 A core-sheath composite having a core-sheath weight ratio of 1/1, which is made of a cationic dyeable yarn of a polyester containing 8% by weight of titanium oxide as a core component and a polyester containing no titanium oxide as a sheath component. After dyeing a 2-way tricot using fibers and spandex, resin (refractive index 1.5) processing with an aqueous urethane resin manufactured by Dainippon Ink and Chemicals, Inc. was performed (resin adhesion amount: 4% owf (vs. fiber)). , Film thickness:
About 0.1 μm). Then, the magnitude of the discoloration was examined. As a result, the color difference between dry and wet was as shown in Table 1.

[0021]

Comparative Example 2 A core-sheath composite having a core-sheath weight ratio of 1/1, which is made of a cationic dyeable yarn of a polyester containing 8% by weight of titanium oxide as a core component and a polyester containing no titanium oxide as a sheath component. After dyeing a 2-way tricot using fibers and spandex, a resin (refractive index 1.55) using a water-based urethane resin manufactured by Dainippon Ink and Chemicals, Inc. was processed. Then, the magnitude of the discoloration was examined. As a result, the color difference between dry and wet was as shown in Table 1.

[0022]

[Comparative Example 3] Cationic dyeable yarn A 2-way tricot using a single-component yarn and spandex was processed in the same manner as in Example 1,
The color was measured. As a result, the color difference between dry and wet was as shown in Table 1.

[0023]

[Table 1]

[0024]

The cloth of the present invention can prevent discoloration of the cloth due to rain or sweat. Therefore, discomfort caused by discoloration caused by water is eliminated.

Claims (1)

[Claims] 1. A core-sheath type composite fiber having a core having a white pigment content of 3% by weight or more and 30% by weight or less and a sheath having a white pigment content of 2% by weight or less, or the core-sheath type. A fabric for preventing discoloration, which is characterized in that a resin film made of a resin having a refractive index of 1.3 to 1.5 is formed on a fabric composed of a composite fiber and another fiber.