JP3057668B2 - Cellulose fiber treatment method and cellulosic fiber with shape obtained by the method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cellulosic fiber having a memorized shape. More specifically, the present invention relates to a shape memory cellulose that hardly decreases the strength and elongation of the fiber, and easily recovers its original shape when immersed in water at room temperature.

[0002]

2. Description of the Related Art Cellulose fibers such as cotton have many features such as good hygroscopicity, low static electricity generation, good dyeing properties, and easy removal of dirt, but have poor form stability against water. It has drawbacks, especially in the case of recycled cellulose fibers such as rayon, which tend to deform when external force is applied under wet conditions,
There was a drawback that it did not return to its original state even after drying. further,
From the viewpoint of the setting properties of the cellulose fiber, even if the cellulose fiber is deliberately deformed and is to be maintained permanently as it is, once exposed to a wet condition, the fiber swells quickly. Deformation distortion was eliminated, so-called permanent press working was impossible, and it was impossible to provide shape memory at all. In order to improve the above-mentioned drawbacks of cellulose fiber, the cellulose fiber has been subjected to a mercerizing process in which the cellulose fiber is subjected to a tension-free treatment with an aqueous solution of caseidose (UK patent 1850).
13396) or mercerizing by tensioning in the same solution (British Patent No. 1890-4452)
was there. More recently, a method of immersing cellulose fibers in liquid ammonia (1966 Norwegian Patent No. 15299, 1966 British Patent No. 5396)
0, 1974 French Patent No. 18331, JP-A-59
163364, JP-A-61-19867, and JP-B-62-12347), and many methods using a thermosetting resin typified by a urea-formalin-based resin as a crosslinking agent are also performed. However, Caseiso-
In the treatment of the aqueous solution and liquid ammonia, there is a defect that a welding phenomenon occurs between the filaments during the treatment, the feel becomes hard, and the cutting elongation and the bending wear strength are reduced. On the other hand, in the processing of urea-formalin-based resin, none of the methods was satisfactory because of the problem of residual formalin after the textile product. In addition, above all, the purpose of these methods is to improve the dimensional stability against water is only a passive treatment of the main purpose, and the purpose is not to provide a shape memory ability that can always recover a preset form. Did not. In addition, a kind of steam treatment called a vacuum set has been performed in the twisting treatment after the twisting of cellulose fibers or the like. This is done by setting a twisting bobbin in a vacuum pot, setting the degree of vacuum in the pot to about 700 to 740 mmHg, and injecting saturated steam to raise the temperature in the pot to 80 to 90 ° C, usually 13
Maintain at 0 ° C. for 15-40 minutes. Next, as a post-vacuum treatment, the pressure is reduced again to 700 mmHg, and then the vacuum is broken to achieve an atmospheric pressure and air cooling is performed. However, this twist stopping process is not a process in which the twist shape is stored.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a cellulosic fiber having a capability of highly recovering a form intentionally given in advance without performing a specific chemical treatment such as an alkali or a resin. The object of the present invention is to provide a shape memory cellulosic fiber intrinsically structured.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above-mentioned object, and as a result, it has been surprisingly found that cellulose fibers treated with high-pressure steam at a predetermined pressure are dried under tension. It has been found that even if it is immersed in water, it has the ability to quickly recover to the shape at the time of processing, and furthermore, depending on the processing conditions, it has been found that the mechanical properties of cellulose fibers are further improved, and the present invention has been reached. did.
In other words, the present invention provides a method for forming cellulose fibers into a certain shape.
3kg / cm ↑ 2-40kg / c while maintaining the shape
A method for treating a cellulose fiber, which comprises subjecting the cellulose fiber to high-pressure steam treatment at m ↑ 2, and a memorized cellulose fiber obtained by the method. In addition, 3kg / cm
The process of steaming at a high pressure of {2 to 40 kg / cm} 2 may be simply referred to as “high-pressure steaming” below.

[0005] The “shape memory ability” developed by the treatment method of the present invention can be considered as follows. That is,
High-pressure water vapor while maintaining a constant shape of cellulose fiber
Air treatment keeps this shape in the cellulosic fiber
I'm sullen. This constant shape is erased by external force.
Even if it is lost, it can be immersed in water,
Can be recovered. For example, when a knitted fabric is made with a yarn made of cellulose fiber, the shape of the constituent yarns in the knitted fabric is regulated and maintained in a continuous crimp (loop) state, and when the high-pressure steam treatment is performed in this state, the shape of the crimp is stored. . When an external force is applied to the yarn with this shape stored, the shape disappears once, but it immediately recovers the original crimp shape when immersed in water, and this shape disappearance and the shape recovery behavior are highly reproducible. It is done reversibly. It should be noted that the shape is not limited to the crimp as described above, and it is clear that various shapes and forms to be stored can be subjected to the high-pressure steam treatment of the present invention. In the present invention, the details of the mechanism by which high-pressure steam treatment develops the shape memory ability are unknown, but are presumed as follows. That is, 20 ° C., 65%
R. H. When the cellulose fibers in the moisture-conditioned state are deformed by an external force, stress distortion occurs in the cellulose molecules inside the fibers. Of course, at this point, if the external force is removed without any treatment, it immediately recovers to the original state before deformation, or swells in the fibers when immersed in water even if there is some shape retention. The deformation is almost eliminated due to the pressure. However, when high pressure steam treatment is performed with external force applied,
The strong hydrogen bonds present in the cellulose molecules in the non-crystalline region or pseudo-crystalline region inside the cellulose fiber are once broken by the action of water molecules, and the strain stress in the molecules is relaxed.
At the same time, it is thought that crystallization newly proceeds in a state where stress strain is not applied to the cellulose molecular chain, and as a result, a shape memory effect at the cellulose molecular level is exerted. In the high-pressure steam treatment of the present invention, the high pressure refers to an absolute pressure in the range of 3 kg / cm2 to 40 kg / cm2, preferably 4 kg / cm2 to 15 kg / cm2.
2 and more preferably in the range of 5 kg / cm @ 2 to 8 kg / cm @ 2. 3 kg of high pressure steam
When the ratio is less than / cm ↑ 2, the shape memory ability is weak, which is not preferable. On the other hand, when the pressure is too high, the shape-memory properties are sufficient, but the strength and elongation are significantly reduced. Particularly, in the present invention, since there is a region where the elongation is improved in the region of the pressure of 3 to 6 kg / cm @ 2, the pressure condition is appropriately set in accordance with the desired balance between the shape memory performance and the elongation. Is preferred. The processing temperature (steam temperature) is uniquely determined physicochemically from the above steam pressure, but when the pressure is 3 kg / cm ↑ 2, it is about 130.
When the temperature is 40 ° C. and the pressure is 40 kg / cm 2, it corresponds to about 250 ° C. When the pressure is high, the processing time is short, and when the pressure is low, a slightly longer processing time is required. Therefore, the processing time cannot be set unequivocally. In the present invention, it is preferable to perform the treatment for a short time under a high pressure condition, because the shape memory property can be enhanced while suppressing the decrease in the elongation. The processing apparatus is not particularly limited as long as it can create an environment of high-pressure steam as described above, and a conventionally known apparatus equipped with a high-pressure kettle can be used.

[0006] The fibers made of cellulose to be subjected to the high-pressure steam treatment of the present invention include natural cellulose fibers such as cotton, hemp, flax, etc., viscose-processed rayon (including polynosic), and copper ammonia. Recycled fibers such as rayon
The effect of the present invention is more remarkably observed when the recycled fiber is treated. Furthermore, regarding the fiber form, various forms of treatment are possible depending on at what stage from the raw yarn to the product the high-pressure steam treatment is performed, for example, cotton, tow,
It may be in the form of a sliver, a spun yarn, a filament, or the like, or may be after forming a textile product such as a woven fabric, a knitted fabric, or a nonwoven fabric. Also, as a special case, even if it is paper-like or film-like, any restrictions should not be imposed as long as it is made of cellulose, and it is applied as long as it does not depart from the gist of the present invention.

The high-pressure steam treatment of the present invention may be applied to a mixture obtained by blending, blending, twisting, weaving or knitting of cellulose fibers and other fibers such as polyester fibers. 50% by weight or more based on other fibers
The effect of the present invention is remarkable in the case of fiber.

The cellulose fiber obtained by the treatment method of the present invention has a unique behavior of shape memory recovery.
Various applications are available, for example, in the case of yarn processing, it can be used for shape memory processing of denit processing or gear processing performed for the purpose of giving bulkiness to the yarn, and it is composed of cellulose If the fiber product is creased and the shape is memorized in that state, the crease can always be recovered by washing. Further, as is apparent from the effects of the present invention, it is needless to mention again that the present invention also has an effect of imparting dimensional stability to water of cellulose fiber, which has been long awaited. It does not cause any problem even if it is used in combination with a case isoda treatment, a liquid ammonia treatment, and a urea-formalin resin treatment.

The shape memory ability of the cellulose fiber of the present invention thus obtained will be specifically described by taking the crimp of the knit denit yarn into account. In the appearance, reproducibility of 10 times or more is assured in appearance, and even after being subjected to severe hot water treatment (about 100 ° C. × 30 minutes), as will be apparent from the following examples. 75% before processing
While the above-mentioned crimps (numbers) are restored, the conventional yarn that has not been subjected to the high-pressure steam treatment has a remarkable difference that the crimps completely disappear by the same hot water treatment. The stretch ratio of the yarn of the present invention is at least 20%, preferably 4%.
On the other hand, the yarn which is not subjected to the high-pressure steam treatment has a low expansion ratio of about 10% while the yarn which is not subjected to the high-pressure steam treatment. The value is more than twice as high as that not received, and not only the recoverability in appearance but also the physical properties are well maintained.

[0010]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. Examples 1 to 9, Comparative Examples 1 and 2, S120 T / m by flattening 300 denier flat yarn / 30 filament viscose rayon long fiber yarns
Was given a twist. In order to process the raw yarn into a denit yarn, a tubular knitting machine was used to make a tubular knitting machine using an Arakawa needle knitting machine (pot diameter: 3.5 inches, number of needles: 90).
After dyeing at 0 ° C for 30 minutes, the knitted fabric was supplied to a horizontal high-pressure kettle having a diameter of 60 cm and a length of 80 cm, and subjected to various changes in high-pressure steam absolute pressure and processing time (Comparative Example 1). Is not subjected to high pressure steam treatment). Thereafter, the tubular knitting net is unknitted, and subjected to a hot water treatment (about 100 ° C., 30 minutes) to remove deformation distortion remaining in the yarn without being fixed.
Then, a dry weight of 0.3 mg / denier was applied to the yarn while it was wet, and the yarn was air-dried. The yarn with no crimp in appearance was immersed again in water at room temperature to perform a shape recovery treatment. Thereafter, the paper was sandwiched between cloths, water was cut out, spread on a wire mesh, dried in a free shrink state, and the crimp recovery property, that is, shape memory property and yarn quality were evaluated. The results are shown in Table 1.

[0011]

[Table 1]

As can be seen from Table 1, those treated according to the present invention exhibited good shape recovery properties and improved yarn quality, but the fibers were crystallized by high-pressure steam treatment. It is thought to be. On the other hand, in the case of the comparative example, the recovery of the crimp shape was poor. In particular, in the case of the comparative example 1, the crimp almost disappeared by the hot water treatment at 100 ° C. for 30 minutes. Here, the number of crimps and the rate of expansion and contraction were used as the evaluation parameters of the shape memory property.
According to the measuring method of 1074-6.11.1 "number of crimps" (1977), the number was expressed as the number of crimps between 25 mm of yarns to which a constant load was applied. However, in this case, the minimum amplitude of the crimp that can be regarded as a peak was set to twice the average yarn width. The expansion and contraction rate is 20 cm between the yarn lengths at an initial load of 0.3 mg / denier.
Was marked, and then the load was changed to 30 mg / denier, the length 1 between the marks was measured, and the expansion ratio was determined as (l-20) / 20 × 100 (%). The stretch rate represents the strength of the crimp elasticity,
The crimped shape is firmer as the value is larger.
The retention rate (%) of the number of crimps and expansion / contraction ratio indicates how much each value is retained before and after the above-mentioned hot water treatment. In other words, it indicates the degree of shape memory. is there.

Examples 10 to 13 , Comparative Example 3 Brightness of viscose rayon filaments of 75 denier /
30 filaments to warp, semi-dal 120 of the same material
Denier / 40 filaments were arranged on the weft and woven in a plain weave structure with a weaving density of 102 yarns / inch × 68 yarns / inch at an air jet loom ZA-103 at 600 rpm. The greige machine was set at this density (without applying tension) to a pin tenter, treated with a desizing agent at 90 ° C. for 30 minutes in a scouring bath containing 1.5 g / l of a nonionic surfactant, washed with water, and then washed with water. Well cut, steam pressure 3kg
/ Cm ↑ 2 was treatment <br/> management of (saturated steam temperature 130 ° C.) within 2 minutes (Example 10). Similarly, the water vapor pressure
(Example 1)
1-13). Next, the fabric after the high-pressure steam treatment was removed from the pin tenter, and was not air-dried.
The same hot water treatment as that described above is performed, and the cloth is spread on a wire mesh and air-dried in a free shrink state.
IS L1042-6.2B method "boiling water immersion method" (198
6 years), and the dimensional stability against water was evaluated. The tear strength of the same type of dry woven fabric is JIS L107.
It is measured at a tensile speed of 20 cm / min according to the 9-6.13.1 method "tear strength" (1976). For comparison, the same treatment as in Example 10 except that the high-pressure steam treatment was omitted (Comparative Example 3) was similarly evaluated. The results are shown in Table 2. According to the present invention, good results with low shrinkage and high tear strength were obtained.

[0014]

[Table 2]

──────────────────────────────────────────────────続 き Continuation of front page (51) Int.Cl. ⁷ Identification code FI D06M 11/05 D06M 1/24 // D06M 101: 06 (56) References JP-A-2-84537 (JP, A) JP JP-A-62-62989 (JP, A) JP-A-51-78851 (JP, A) JP-A-49-30642 (JP, A) JP-A-49-61488 (JP, A) JP-B-47-44451 (JP, A) , B1) JP-B-44-32025 (JP, B1) JP-B-41-319 (JP, B1) (58) Fields investigated (Int. Cl. ⁷ , DB name) D02G 1/00-3/48 D02J 1/00-13/00 D06B 1/00-23/30 D06M 11/00-11/84 D06M 16/00

Claims (4)

(57) [Claims] Claims: 1. A cellulose fiber having a predetermined shape.
3kg / cm ↑ 2-40kg / cm while maintaining
# 2. A method for treating cellulose fibers, which comprises treating with high-pressure steam. 2. Cellulose fibers having a shape obtained by the method according to claim 1. (3) Cellulose fibers are made into a certain shape
3kg / cm ↑ 2-40kg / cm while maintaining
By treating with high pressure steam of # 2, cellulose
The fibers keep the certain shape, and the certain shape is
Even if it disappears due to
Characterized by being able to recover the shape of the cellulos
Processing method of raw fiber. (4) Cellulose fibers are made into a certain shape
3kg / cm ↑ 2-40kg / cm while maintaining
# 2 obtained by treating with high-pressure steam.
A cellulosic fiber having a certain shape, wherein the cell
Loin fiber, when the certain shape disappears due to external force
But, by immersing in water, the certain shape can be recovered
Cellulose fiber characterized by the above-mentioned.