JPH02200816A - Polyamide conjugate yarn - Google Patents

Abstract

PURPOSE:To obtain the title conjugate yarn having excellent fastness to light, fastness to wetting, yellowing preventing ability and wide utility, having a higher amino end content of core component than that of sheath component and comprising a specific amount of amino end group of the sheath component. CONSTITUTION:A polyamide component such as nylon 4 or nylon 6 is subjected to conjugate spinning and formed into core-sheath yarn having the weight ratio of sheath component and core component of (10:90)-(50:50), a higher amino end content of the core component larger than that of the sheath component and 5-20mg equivalent/kg amino end content of the sheath component to give the aimed conjugate yarn having excellent light resistance, improved fastness to wetting and excellent level dyeing properties.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a polyamide conjugate fiber that has excellent light fastness, wet fastness, and anti-yellowing ability of dyed products.

[Prior art and problems to be solved by the invention] Conventionally, polyamide fibers such as nylon 6 and nylon 6.6 have been known for their excellent color development, strength, transparency, abrasion resistance, and flexibility. Due to its adhesive properties, it has been widely used in industrial applications such as tire cords, fishing nets, and computer ribbons, clothing applications such as socks, innerwear, ski wear, and swimwear, and material applications such as umbrellas and bag fabric.

In particular, for sports applications such as ski wear, leotards, and swimwear, not only are there demands for physical properties such as strength and flexibility, but also as fashion orientation increases.
The colors, especially the vibrancy of the colors.

Demand for depth has become particularly strong.

Polyamide fibers can be dyed with a variety of dyes, including acid dyes, metal complex acid dyes, disperse dyes, reactive dyes, and chromium dyes, but acid dyes are usually used in areas where brightness and depth are required. . However, in this case, it has been pointed out that the dyed product has poor light fastness and wet fastness, typified by washability and wet friction.

As a means of improving such light fastness, there are methods of treating polyamide fibers with a treatment agent containing a copper ion compound and a method of treating the polyamide fiber with a treatment agent containing an ultraviolet absorber, but none of them are sufficiently effective. The method of treating with a treatment agent containing a copper ion compound has the problem that the hue of the dyed product changes significantly, and the color becomes dull and lacks clarity.

On the other hand, as a means to improve wet fastness, treatments include fiber fixing agents that have an affinity with polyamide fibers but have no affinity with acid dyes, such as compounds with phenolic hydroxyl groups, sulfonamide compounds, and carbodiimide compounds. A method of treatment with a chemical agent is commonly used.

However, although this method has the effect of improving wet fastness, there is a problem in that the fiber fixing agent itself is brown, and the dyed product after treatment is colored brown and the color becomes dull. On the other hand, another demand is for polyamide fibers that are resistant to yellowing. It has been pointed out that polyamide fibers are more susceptible to yellowing than other synthetic fibers such as polyester fibers and acrylic fibers due to environmental pollution gases such as NOx, carton cases, and polypropylene packaging materials containing antioxidants. .

As a means to improve the ease of yellowing,
No. 5-47150 discloses a method of treating polyamide fibers with a colorless compound that does not have a reactive group covalently bonded to the terminal amino group and contains an anionic active group consisting of a sulfonic acid group or a sulfuric acid ester group. There is.

Although this method does have an anti-yellowing effect, there are problems such as the effect disappears when washed, etc., and it is not effective when raw yarn or knitted fabrics are stored before the anti-yellowing treatment.

JP-A-58-220817 discloses core-sheath type polyamide fibers having different amino end groups, in which the amount of amino end groups in the sheath component is 55 mg equivalent/kg or less, and the amount of amino end groups in the core component is 60 mg equivalent/kg or more. A method for producing a polyamide fiber in which the core component accounts for 30% or more and 95% or less in the cross section of the fiber is disclosed.

The polyamide fiber achieves the clarity and depth of the color of the dyed product, but if the amount of amino terminal groups in the sheath component is less than 55 mg equivalent/kg or about 4 hg equivalent/kg, the light fastness and washing fastness are poor. There was no improvement, and as seen in this example, it is clear that this was achieved by adding tannic acid to the core component and adding and mixing an ultraviolet absorber to the sheath component.

Furthermore, no yellowing prevention effect was observed in the polyamide fibers.

The object of the present invention is to avoid the above-mentioned drawbacks, that is, to maintain the clarity and depth of dyed products, and without adding any light fastness or wet fastness improvers such as ultraviolet absorbers or tannic acid. An object of the present invention is to provide a versatile polyamide fiber having excellent light fastness, wet fastness, and anti-yellowing ability.

[Means for Solving the Problems] In order to solve the above problems, the present invention has the following configuration. That is, in a core-sheath type polyamide composite fiber in which the weight ratio of the sheath component to the core component is 10:9G to 50:50, the amount of amino terminal groups in the core component is larger than the amount of amino end groups in the sheath component, and The amino terminal group amount of the component is 5 to 2 hg equivalent/kg
It is a polyamide composite fiber characterized by the following.

The polyamide components used in the polyamide composite fiber of the present invention are ordinary synthetic linear polyamides, such as nylon 4, nylon 6, nylon 11, nylon 12, nylon 6.6, nylon 6.10, nylon 4.6, Examples include nylon 6.T (polyhexamethylene terephthalamide) and copolymers or blends containing these as main components.

In the present invention, the conjugate fiber means a core-sheath type conjugate fiber.

In the polyamide composite fiber of the present invention, the weight ratio of the sheath component to the core component must be 10:90 to 50:50. If the sheath component is less than 10% by weight, there will be problems in measuring the sheath component during melt spinning, which will not only make it difficult to spin composite fibers with a uniform structure, but also cause the sheath component polymer to remain in the spinning machine. This is undesirable because it takes a long time and causes thermal deterioration, and in some cases, some portions of the core component are not covered with the sheath. In addition, light fastness, wet fastness, and anti-yellowing ability are also lost. On the other hand, if the sheath component exceeds 50%, the sheath becomes too thick relative to the core, resulting in less dye exhaustion and resulting in a dyed product lacking clarity and depth.

In the polyamide composite fiber of the present invention, the amount of amino terminal groups in the core component must be greater than the amount of amino terminal groups in the sheath component. When the amount of amino end groups in the core component is equal to the amount of amino end groups in the sheath component, those with a high amount of amino end groups tend to yellow, and those with a low amount of amino end groups have the problem of not being able to obtain a deep color. . In addition, when the amount of amino terminal groups in the core component is smaller than the amount of amino terminal groups in the sheath component, the polyamide conjugate fiber of the present invention has a problem of yellowing easily, and the amount of amino terminal groups in the polyamide used as the sheath component is required to be 5 to 20 mg equivalent/kg, and 5 to 10 mg equivalent/k
More preferably, it is g. If it exceeds 2hg equivalent/kg, not only the effect of improving light fastness is lost, but also the ability to prevent yellowing is lost.

On the other hand, it is generally difficult to obtain a polyamide having an amino terminal group content of less than 5+1 g equivalent/kg.

In the polyamide conjugate fiber of the present invention, the matting content of the polyamide used as the sheath component is set at 0°05 weight from the viewpoint of effectively utilizing the appearance of color due to the dye coloring of the core component and from the viewpoint of further improving light fastness. % or less. As the matting agent, titanium oxide, barium sulfate, etc. are preferably used.

The cross-sectional shape of the polyamide composite fiber of the present invention can be determined whether the core and sheath components are composite, whether each component is circular or irregularly shaped, or whether one of the components is circular and the other is irregularly shaped. Even if there is, the effects of the present invention can be fully exhibited.

The number of filaments and fineness of the polyamide composite fiber of the present invention are selected depending on the field of application of the product, but in order to fully exhibit the effects of the present invention, the thickness of the sheath component must be 0.5
It is preferable that the thickness is µm or more.

As a method for producing the polyamide composite fiber of the present invention, it may be produced by a method of first winding a filament spun as an undrawn yarn by a conventional core-sheath type composite spinning method and then drawing it. Currently, nylon is being produced using a direct spinning/drawing method in which the above-mentioned spun yarn is drawn and wound without being wound up, or a direct high-speed manufacturing method in which the spun yarn is wound at a speed of 4000 m/sin or higher without being drawn. 6. Nylon 6.6
It is possible to use a known manufacturing method that has been applied as a silk reeling process.

Next, the present invention will be explained in more detail with reference to Examples.

As measurements for determining the effects of the present invention, color development, light fastness, washing fastness, and yellowing were measured using the following methods.

Method for Measuring Color Development The L value of the dyed product was measured using a Suga Test Instruments ■ADD-3CH-2 model digital colorimeter. The smaller the number, the darker the color.

(2) Measurement method for light fastness: Measured by JIS L 0842 3rd exposure method (63°C).

■Measurement method for washing fastness Measured according to JIS L 0844 (method A-2).

■ How to measure the degree of yellowing: Sandwich the knitted fabric between cardboard boxes from both sides, 60℃, 90%RH.
The yellowness of the knitted fabric before and after the cardboard treatment was measured using a colorimeter used to measure color development, and the degree of yellowing was calculated.

Note that the degree of yellowing (%) is expressed by the following formula.

Yellowing degree (%) = (Yellowness after cardboard treatment) - (Yellowness before cardboard treatment) The yellowness in the formula refers to X and Y observed with a color difference meter.

Using Z, the value is (1,211x-1,OH)/Y. When the degree of yellowing (%) is 1.0 or more, yellowing can be detected with the naked eye, so for practical purposes, the degree of yellowing (%)
) is 1. There is no effect unless it is below O.

[Example] (Example 1) By melt polymerization, the amount of amino terminal groups was 5.1. 1G, 3°19.8. 3G, 5. Nylon 6 chips with a titanium oxide content of 0.02% by weight at 40.71g equivalent/kg,
A nylon 6 chip containing 0.2% by weight of titanium oxide with an amino terminal group amount of 5G and 4 mg equivalent/kg was obtained. Using a composite spinning machine, chips melted at 265°C are mixed with core and sheath components as shown in Table 1, and a core-sheath composite ratio of 8G/
20% by weight and was spun at a speed of 900 i/+++in to obtain an undrawn yarn with a concentric core-sheath composite structure. This undrawn yarn was drawn at a speed of 400 m/n+in and a magnification of 3.3 times to obtain a drawn yarn of 50 denier and 40 filaments. A tubular knitted fabric is made using these fiber yarns, and after scouring and intermediate setting in the usual manner,
g RedR31250, 05% owl), blue (X
ylene Fast Blue P2, θ%owl)
, black (Ka2akatan Black aGL 5
．． The samples were dyed at 100° C. for 60 minutes using an acid dye (0% 0WE) and a metal complex acid dye, and the color development (L value), dye fastness, and degree of yellowing of the intermediate set product were examined.

Table 1 shows the color development, color fastness and yellowing of the knitted fabric.

As is clear from Table 1, when the amount of amino terminal groups in the pod component exceeds 2hg equivalent/kg, which is a comparative example of Nα4.5, the color development is high, but the light fastness and washing fastness are not only low. It can be seen that it is prone to yellowing. Nα1～
It can be seen that the examples of the present invention up to No. 3 have excellent light fastness and washing fastness, are resistant to yellowing, and have sufficient color development.

Example 2 Il/10.3 mg of amino terminal group used in Example 1
kg, nylon 6 chips with a titanium oxide content of 0.02% by weight are used as the sheath component, and the amino terminal group amount is 50.4 mg equivalent/
Using nylon 6 chips with a titanium oxide content of 0.2% by weight as the core component, spinning and drawing were carried out in the same manner as in Example 1 to obtain a concentric core-saya composite with a core/saya composite ratio as shown in Table 2. A drawn yarn having a structure of 70 denier and 24 filaments was obtained. Separately, for comparison, a single yarn of a core component polymer and a single yarn of a sheath component polymer of 70 denier and 24 filaments were obtained by spinning and drawing in the same manner.

A tubular knitted fabric is made using these fiber yarns, and after scouring and intermediate setting using the usual method, it is dyed blue (X71eneFgsl).
The material was dyed using an acidic dye (Blue P 2°0% ovf) at 100°C for 60 minutes, and the color development (L value), dye fastness, and degree of yellowing of the intermediate set product were examined and shown in Table 2. .

As is clear from Table 2, when the weight ratio of the sheath component polymer, which is a comparative example of Nαto,it, exceeds 50%,
It can be seen that the color development is low and the fastness to washing is also low. Nα12, which is a comparative example, has low color development and fastness.
It can be seen that Nα13 has low light fastness and easily yellows. Furthermore, Comparative Example Nα6 suffers from thermal deterioration, has a yellowish tinge, has low strength, and is easily yellowed. It is recognized that Nα7 to Nα9 of the present invention have high color development, excellent light fastness and washability, and are resistant to yellowing.

[Effect of the invention] In core-sheath type polyamide conjugate fibers with different amounts of amino terminal groups, color development can be improved by specifying the amount of amino terminal groups in the sheath component, the amount of matte content, and the weight ratio of the core component and the sheath component. While maintaining the same properties, it has improved light fastness and wet fastness, is less prone to yellowing, and has excellent level dyeing properties.

Claims (1)

[Claims] (1) Weight ratio of pod component to core component is 10:90 to 50:
50, the amount of amino terminal groups in the core component is larger than the amount of amino terminal groups in the sheath component, and the amount of amino terminal groups in the sheath component is 5 to 20 mg equivalent/kg. Characteristic polyamide composite fiber.