JPS5846119A - Crimped composite fiber and its preparation - Google Patents

Abstract

PURPOSE:To obtain the titled fibers capable of changing the percentage crimp reversibly, by subjecting polyethylene terephthalate copolymerized with 5-sodium sulfoisophthalate and nylon 6 to the composite spinning, directly drawing, heat- treating the fibers, and heating the resultant heat-treated fibers at a somewhat lower temperature than in the heat-treating step to develop crimps. CONSTITUTION:(2) A modified polyethylene terephthalate copolymerized with 5-sodium sulfoisophthalate and (1) nylon 6 component are subjected to the composite spinning in the form of side-by-side type, and the resultant fibers are without winding continuously drawn at 95 deg.C or below, heat-treated at 100 deg.C or above under tension or relaxed conditions <=10% and then heated at 10 deg.C lower than the heat-treating temperature under <=20mg/denier tension or relaxed conditions to develop crimps and give the aimed fibers having (1) the nylon 6 component positioned on the inside of the crimps and >=3 X-ray diffraction intensity ratio[I(020)/I(040)]of the nylon 6.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a crimped conjugate fiber whose crimp rate changes reversibly with temperature changes and a method for producing the same, and more specifically relates to a crimped conjugate fiber whose crimp rate changes reversibly with temperature changes, and more specifically relates to a crimped composite fiber that is copolymerized with 5-sodium sulfoisophthalic acid. This invention relates to a side-pie-side type composite fiber of polyethylene terephthalate and nylon 6, which increases the crimp rate by drying and decreases by absorbing moisture, and a method for producing the same. .

It has been well known that the crimp rate of natural fibers such as cotton, wool, and feathers changes reversibly with changes in humidity. These natural fibers are often used as filling cotton for futons, pillow padding, and anti-fight clothing, but they have the drawback of being easily damaged by insects, and furthermore, they are difficult to use. There is a drawback that the crimp rate becomes large during the drying process, and the crimp rate decreased due to humidity is not sufficiently restored even after drying.

On the other hand, crimped fibers made of synthetic fibers are also used for stuffing and filling, but in general, synthetic crimped fibers have a reversible crimp rate with respect to humidity, and the fibers become entangled with each other during use. It has the disadvantage that it becomes spherical and its identity cannot be recovered. In order to prevent such entanglement of fibers, the crimp rate is lowered, a smoothing oil is applied, or the fibers are opened in a tow state, but these methods are not sufficient. After using it for 2 to 3 years, it will start to wear out.

Furthermore, it is known that acrylic synthetic fibers can be used to obtain a stuffed cotton whose crimp rate increases reversibly upon drying (Patent Publication No. 55-93860). In order to do this, it is necessary to modify one of the acrylics to make it hygroscopic, which has the major disadvantage of not only being expensive but also that acrylics inherently tend to wear out.

The inventors of the present invention have conducted intensive studies to solve this problem, and as a result, we have developed a specific poly7-gamma component and a polyester component.
By spinning pie-side composite fibers, we are able to utilize the functionality of synthetic fibers, such as insect-proofing, clump-free properties, the ability to adjust the properties as desired, and the ability to freely select the fineness range. The present inventors have discovered that it is possible to obtain a crimped fiber that reversibly changes its crimp rate with changes in humidity, like natural fibers, by taking advantage of its high elasticity and elasticity, and has thus arrived at the present invention. .

That is, the present invention 1 is a side-pie-side type composite fiber consisting of modified polyethylene terephthalate copolymerized with 5-sodium sulfoinphthalate and nylon 6, in which the nylon 6 component is located inside the crimps. , corresponding≠ip
X11 diffraction intensity ratio of 6 components 1 (02G) / I
(040) is 3 or more, and modified polyethylene terephthalate combined with 5-sodium sulfoisophthalate and nylon 6 in a side-pie-side type? It is spun and drawn continuously without winding once at a temperature of 95°C or lower, then subjected to tensioning or relaxation heat treatment of 10% or less at a temperature of 100°C or higher, and then 10% higher than the heat treatment temperature.
A method for producing crimped composite fibers, which comprises heating at a temperature lower than or equal to .degree. C. under a tension of 20 cm/de or less or in a relaxed state to develop crimps.

Furthermore, modified polyethylene terephthalate copolymerized with 5-sodium sulfoisophthalic acid and nylon 6 were composite-spun in a side-by-side type, and the yarn was continuously spun without being wound up.

Stretched at a temperature below 10°C, then subjected to tension or relaxation heat treatment at a temperature below io'o°C, then i
This is a method for producing crimped conjugate fibers, which has four characteristics: developing heating μ crimp under a tension of zowg/ae or less or in a relaxed state at a temperature of oo°C or less.

The crimped conjugate fiber of the present invention is a side-pie-side conjugate fiber made of nylon 6 and modified polyethylene terephthalate copolymerized with 5-sodium sulfoisophthalate. Both of these polymers have good adhesion when made into composite fibers, and no peeling occurs, and by combining these two, it is possible to obtain composite fibers whose crimp ratio changes reversibly and significantly with changes in humidity. I can do it.

Normally, nylon 6 has an intrinsic viscosity (1'l (measured with m-cresol solution at 30°C) of 1.0 to 1.417), and the other component is 5-sodium sulfoisophthalic acid-modified polyethylene. Terebutane has an intrinsic viscosity [η] (determined with an O-ri I:I phenol solution at 25°C) of 0.4゛0'S-o,
A copolymerized amount of sodium sulfoisophthalic acid of 15 mol or less is used. The copolymerization amount of 5-sodium sulfoisophthalic acid is particularly preferably 1 to 7 mol. A matting agent, a coloring agent, an antistatic agent, a heat stabilizer, etc. can be added to these two components as necessary.

Such side pipes of nylon 6 and 5-sodium sulfoisophthalate modified polyethylene terephthalate.
The side type composite fiber itself is already %kosho 4'5'-'1
1.8? It is known from Japanese Patent No. 29, Publication No. 11846-847, etc., but in these known composite fibers, there is almost always a reversible change in the crimp rate due to a change in humidity. The most significant feature of the present invention is that among these five known composite fibers, the X1Ii! The point is that the diffraction intensity ratio 1 (02'O'')/■ (040: ) is 3 or more, preferably 5 or more. , preferably 5 or more, only when a
Reversible and practically necessary degree of winding due to ID change,
Change in shrinkage ratio, i.e. 60°C.

Curling rate after drying for 30 minutes: 30℃ relative humidity 5oIs
The crimp rate changes to be 5 oIs or more higher than the crimp rate after being left in the atmosphere for 2 hours.

Here, the X-ray diffraction intensity ratio! ,'(0,20)/I(04
G) is a value determined from the X-ray wide-angle diffraction intensity in the meridian direction (Fig. 1) measured for the nylon 6 component of the crimped composite fiber. That is, in the case of nylon 6, as shown in Figure 1, the diffraction angle 2θ is 1α8@ ('020
), and the diffraction intensity peak of (040) appears at a diffraction angle of 2θ of 21.4°. A straight line A connecting the diffraction intensity at 40" was measured as the baseline, and I(020) and I, respectively.
(040), and calculate the X leg diffraction intensity ratio I(ozo)/I(
o4o).

X-ray diffraction intensity ratio I (020) of nylon 6 components in conventionally known nylon 6 and 5-sodium sulfoisophthalic acid-modified polyethylene terephthalate crimped composite fibers
/I (040) is usually 1.2 to 20, and there are no known cases where the value is 3 or more.

Furthermore, the crimped composite fiber of the present invention has a structure in which the nylon 6 component 1 is located inside the crimps and the modified polyethylene terephthalate component 2 is located outside the crimps, as shown in FIG. Take. When this crimped composite fiber dries, the inner nylon 6 component 1 shrinks, but the outer modified polyethylene terephthalate component 2 hardly changes in length.
The crimp rate increases. On the other hand, when the crimped composite fiber is mathematically applied, the inner nylon 6 component 1 elongates, and the length of the outer modified polyethylene terephthalate component 2 hardly changes, resulting in a decrease in the crimp rate. Become.

Further, the crimped composite fiber of the present invention can have any fineness, any cross-sectional shape, and any composite form. FIG. 3 is an enlarger-sectional view showing some examples of crimped composite fibers of the present invention;
1 is a nylon 6 component, and 2 is a modified polyethylene terephthalate component. Normally, fibers with cross-sections such as (a), (p), and (c) are used because they are easy to spin, but when it is necessary to increase the cross-section of fibers that are sensitive to humidity.
It is effective to form a composite fiber with a cross section in which the nylon 6 component 1 is wrapped in the modified polyethylene terephthalate component 2, as shown in (d). In addition, contrary to (d), 2 modified polyethylene terephthalate components are added to 1 nylon 6 component.
If the cross-sectional shape is made to wrap around the fiber, it will become a composite fiber that responds quickly to humidity. Furthermore, if a hollow composite fiber like (e) is used, the sensitivity to humidity will be too high, and the properties will also be large. Although the composite ratio of both components can be selected arbitrarily, it is usually used in the range of 30'near 0 to 70:30.

It is composed of such nylon 6 and modified polyethylene terephthalate, and the nylon 6 component is located at one position inside the crimp, and the X-ray diffraction intensity ratio of the nylon 6 component is I (020
, ) / I (040) is 3 or more crimped composite fiber is produced by composite spinning modified polyethylene terephthalate copolymerized with 5-sodium sulfoin heptatalic acid and nylon 6 in a side-pie-side type. It was stretched continuously at a temperature of 95° C. without being wound up, and then.

A tension or relaxation heat treatment of 1 Oqb or less is performed at a temperature of 100°C or higher, and then heating is performed at a temperature 10°C or more lower than the heat treatment temperature under a tension of 20 Whg/de or lower or in a relaxed state to generate crimp. It can be easily manufactured by making it shallow.

As mentioned above, the drawn composite fiber is subjected to tensioning or relaxation heat treatment at a temperature of less than 100°C, and then
It may be heated at a temperature of 00° C. or less under a tension of 20 m9/d· or less or in a relaxed state to develop crimp.

Modified polyethylene terephthalate and nylon 6 are composite-spun in a side-by-side type and stretched at a temperature above the glass transition point (Tg) of nylon 6 and below 95°C. If the stretching temperature exceeds 95°C, the degree of orientation of the modified polyethylene terephthalate component will not increase, and the film will be easily deformed by physical stress during use, and the crimp performance will be poor. The stretching ratio may be appropriately selected so that the elongation at break of the finally obtained crimped composite fiber is 10 to eo%, usually 20 to as%.

This drawing ratio naturally changes depending on the spinning speed in the spinning process, and generally, the higher the spinning speed, the lower the applied drawing ratio.

In the present invention, it is preferable to adopt the direct spinning 11E drawing method in which spinning and drawing are performed continuously, and to adopt a spinning speed that makes the X-ray diffraction intensity ratio of the nylon 6 components 3 or more. . Even when the yarn is wound up after spinning and then stretched, if the yarn is spun at high speed, the Xls diffraction intensity ratio of the six components of nylon can be reduced to 3.
It becomes possible to do the above. If neither direct spinning nor high-speed spinning is possible, using a non-aqueous so-called straight oil as the oil applied during the spinning process will improve the quality of nylon 6.
A composite fiber having a component X* diffraction intensity ratio of 3 or more can be obtained.

The use of a non-aqueous oil prevents water from penetrating into the nylon 6 component, resulting in the structure of nylon 6 similar to that obtained by the direct spinning method, with an X-ray diffraction intensity ratio of I(02G)/I.
It is considered that it becomes easier to obtain a nylon 6 component having (04G) of 3 or more.

The drawn conjugate fiber thus obtained is subjected to tensioning or relaxing heat treatment at a temperature of 100° C. or more or less than 100° C. or less. If the relaxation in this heat treatment step is too large, sufficient crimp will not develop. Then 1
If heat treated at 00℃ or higher, zoq/do at a temperature 10℃ or more lower than this heat treatment temperature, and if heat treated at less than 1'00℃, zoq/do at a temperature of 100℃ or lower.
The crimp is developed by heating under the following tension or in a relaxed state; in this case, the previous heat treatment temperature is increased to 10'O℃
The carp has the above conditions, and the heating temperature during the crimp development treatment is at least 10 degrees Celsius lower than the heat treatment temperature, and the heat treatment temperature is less than 100 degrees Celsius, and the heating temperature during the crimp development treatment is 100 degrees Celsius or lower. Only when the temperature is set to , it is possible to form a slanted structure in which the nylon 6 component is located inside the crimp.

If this is the case, the shrinkage rate of the polyester side during crimp development will increase, and a structure in which the nylon 6 component is preferably located inside the crimp cannot be achieved. Therefore, the temperature at which crimping occurs must be 1'0° C. or more lower than the temperature during stretching heat treatment, and the shrinkage rate of the nylon 6 component must be greater than that of the polyester component. The most effective conditions are to raise the setting temperature during stretching to around 12Q to 160°C, to fully set the polyester component, and to perform the provisional crimp development conditions in boiling water, the shrinkage rate of the polyester component will be low. When it is rolled out, the nylon 6 component has a large shrinkage rate, forming a structure that is positioned inside the crimp.

On the other hand, when the stretching heat treatment temperature is 100° C. or lower, the polyester component is not sufficiently heat-set, so the subsequent heat shrinkage rate becomes high.

Therefore, the K at which the polyester component has smaller heat shrinkage than the nylon 6 component is the temperature at which crimp occurs, which is at least 100%.
℃ or below, preferably lower than the glass transition point Tg of the polyester component and nylon 6
Temperatures higher than the Tg of the components, ie from 40 to 60°C, are good.

[The obtained crimped fiber has the nylon 6 component located inside the crimps, the modified polyethylene terephthalate component located outside the crimps, and the X-ray diffraction intensity ratio of the nylon 6 components I. (az, o)/r (o,, a, o > is 3
As described above, a crimped conjugate fiber is obtained which has five properties such as improved Wl,...$ ratio by drying. Therefore, if this crimped fiber is used for stuffing or padding, even if the electrical property decreases due to use or storage, the electrical property will be greatly restored by drying in the sunlight (:5). And - comes out.

Hereinafter, the present invention will be explained in more detail with reference to examples, and the crimp ratio (TC) and bulkiness shown in the examples were measured by the following method.

B) Crimp ratio (TC) A crimped composite fiber yarn is placed in a 30 cR long tail, and 289
The zooIIIP/d・
Apply a load of The crimp rate (TC) is calculated using the following formula.

In addition, in the examples, when referring to moisture absorption rate, it is 30℃.
It means the maa rate measured by the above method after drying at 260° C. for 30 minutes under a relative humidity of 9411 qb atmosphere.

(b) Cut the bulky crimped composite fiber into 51io+ long lengths and make a card K.
The applied web 180J9 is 30cIL x 3'0 (jl
Put it in a cotton p-do bag to make it look like a futon, and put 3 pieces on top of it.
Place an iron plate measuring 0 cm x 30 c#L and weighing 9 yen, and measure the height of the futon after 1 minute to determine the bulkiness value. The term "a-wet bulkiness" refers to the bulkiness measured by the above method after drying in an atmosphere of 30° C. and relative humidity of 90 qb for 2 hours and several 30 minutes.

Example 1 The intrinsic viscosity [η] was 0.5 (measured with m-cresol nylon 6 at 30'C and o7L polyenol solution at 2s°C'), and the Modified polyethylene tere-7-thalerate copolymerized with 5-sodium sulfoinphthalate was spun using a conventional method at a spinning temperature of 28 I)°C and a spinning speed of 280°C.
Picked it up in 7 minutes, '130do/48fi? An undrawn composite fiber of Mento was obtained.

The cross-sectional shape of the obtained undrawn conjugate fiber was as shown in Figure 3 C-a).・Heated for 20 minutes at a tension of After the undrawn conjugate fibers are wound up, they are drawn by two methods: one is a separate drawing method, and the other is a separate drawing method. Experiments were carried out by varying the temperature of the treatment for developing temperature crimp. Regarding the obtained crimped composite fibers, the moisture absorption crimp rate (TC), dry crimp rate (TC), X-diffraction intensity ratio I (020
)/I(040) was measured. The results are shown in the table below.

After cutting to length and making card weds by applying card k, 3
012II x 30cs cotton pud bag k '1110
A load of *og7- was applied, and the height was measured by applying a load of *og7- to the pillow, making it into a futon shape, and measuring the change in bulkiness during drying and moisture absorption. The results are shown in the table below.

From the above results, it was found that 1'
Heat treatment at a temperature of O'O°C or higher [1st, crimping at a temperature lower than the heat treatment temperature by 10°C or more, followed by crimp development treatment at a temperature of 100°C or lower, the obtained crimped composite fibers The X-ray diffraction intensity ratio of the nylon 6 components is 3 or more, and the nylon 6 components are located inside the crimp, and the crimp rate increases when drying. It can be seen that they exhibit a different property of increasing bulkiness.

[Brief explanation of drawings]

Fig. 1 is a graph showing an example of the X-ray wide-angle diffraction intensity curve of the nylon 6 component of the crimped conjugate fiber of the present invention, Fig. 2 is an enlarged perspective view of the crimped portion of the crimped conjugate fiber of the present invention, and Fig. 3 FIG. 1 is a cross-sectional view showing an example of a crimped composite fiber of the present invention. 1. Nylon 6 component 2... Variable polyethylene terephthalate component copolymerized with 5-sodium sulfoisophthalic acid

Claims (1)

[Scope of Claims] 1) A side-pie-side type composite fiber consisting of modified polyethylene terephthalate copolymerized with 5-sodium sulfoisophthalate and nylon 6, in which the nylon 6 component is on the inside of the crimps. and the nylon 6
The X-ray diffraction intensity ratio I(02G)/I(04G) of the components is 3
A crimped composite fiber characterized by the above. 2) The copolymerization amount of 5-sodium sulfoisophthalic acid is 1
The crimped composite fiber according to claim 1, which has a molarity of 7 to 7 mol. 3) The crimp rate after drying at 60°C for 30 minutes is at least ao% greater than the crimp rate after dilated for 2 hours in an atmosphere of 30°C and relative humidity so%. The crimped composite fiber according to item 1 or 2. 4) Modified polyethylene terephthalate in which 5-sodium sulfoisophthalic acid was combined with nylon 6 was composite-spun in a side-by-side type, and it was continuously stretched at a temperature of 95°C or lower without being looked at. , then 10
A tension or relaxation heat treatment of 5 oqb or less is performed at a temperature of 0°C or higher, and then a tension of -20 qi/d· or lower is applied at a temperature 10°C lower than the heat treatment temperature! Or a method for producing crimped composite fibers, which focuses on heating in a relaxed state to develop crimp. S) Modified polyethylene terephthalate in which S-sodium sulfoisophthalate is combined with nylon 6 is composite-spun in a side-pie-side type, and continuously spun at a temperature of 9°C or lower without being rolled up. Ugishin, then 1-
Apply tension or relaxation heat treatment at a temperature below 00°C, and then apply 20 da/do at a temperature below 100°C.
A method for producing crimped composite fibers, which involves heating under the following tension or in a relaxed state to develop crimps.