JPS6331588B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing short fibers having sharpened fiber ends, which are most suitable as pseudo-animal hair fibers.

Currently, animal hair fibers such as animal hair used in brushes and brushes, angora fibers used in high-quality knitted fabrics, and mink fibers used in furs all have thin tips, so-called tapered shapes. It is well known that the central part is thick and has a waist and flexibility. Various methods for sharpening synthetic fibers have been proposed in order to make the appearance and physical properties similar to those of animal hair. However, these methods generally have the following drawbacks: (1) It is difficult to obtain a good sharp shape, (2) They are expensive because they require special equipment and labor, and are difficult to mass-produce. are doing. On the other hand, in conventional methods, only one end of the fiber is sharpened. For example, Japanese Patent Publication No. 50-40195 proposes a method of sharpening polyester fibers by utilizing their hydrolyzability and capillary development. The sharpened fibers obtained by this method have substantially point-like sharpened portions, and according to this method, good sharpened fibers that are gently sharpened into a symmetrical shape can be obtained. However, in this method, only one end can be sharpened at a time, so to obtain a fiber with both ends sharpened, it is necessary to perform the treatment twice, which is not only uneconomical, but also requires the second treatment. However, the major drawback is that the sharpened shape generally deteriorates due to decomposition products or operational problems. Another disadvantage of the two-time treatment method is that it is only successful for relatively long fibers being treated. Of course, even if the double-end sharpened fibers obtained in this manner are used in raised fabrics, they do not produce a good natural animal hair texture.

In view of these points, the inventors of the present invention have made extensive studies and have discovered a method of the present invention for producing fibers having both ends well sharpened.

That is, an object of the present invention is to create a pseudo-animal hair with sharpened ends like natural animal hair, in order to give the fabric a feel and appearance that is extremely similar to animal hair when used in a raised fabric. In obtaining the fiber, (1) the tip is substantially point-like and has a gently sloped good sharpened shape, and (2) the sharpened shape of each end is substantially the same. (3) To provide a method for easily producing in large quantities with high reproducibility in a single step.

In order to achieve this object, the method for producing a fiber with sharpened ends according to the present invention is constructed as follows.

In other words, continuous fibers are made of polyester fibers, have thick and thin portions periodically in the fiber longitudinal direction, and have a thick/fine ratio of 4 or more and 50 or less (hereinafter, these fibers are referred to as thick/fine fibers). By immersing a yarn consisting of a hydrolyzing agent in a treatment solution containing a hydrolyzing agent and treating it under conditions for hydrolyzing the fiber, the continuous yarn is divided at the thin portion and the divided end is separated. This is a method for producing a fiber with sharpened ends, which is characterized by sharpening the fiber, and specifically,
For example, it is described in Japanese Patent Application Laid-Open No. 54-160841,
Polyester thick and fine fibers with a thick-to-fine ratio of 4 or more and 50 or less and a thick-to-fine period of 5 mm or more and 100 mm or less as shown in the publication are immersed in a treatment solution containing a hydrolyzing agent in the form of a skein, etc., and the fibers are hydrated. By treating the thick and thin fibers under decomposition conditions and uniformly hydrolyzing them in a single treatment, a large number of short fibers with sharpened ends can be obtained. However, in the present invention, it is not necessarily necessary to continue the treatment until the fibers are completely shortened, and it is also possible to stop the treatment just before shortening the fibers and then use a means such as applying slight tension to cut the fibers. good.

In addition, in the present invention, the above-mentioned thick/fine ratio refers to the case where the cross-sectional area of a thick/thin single fiber when cut perpendicular to the fiber axis is measured in the longitudinal direction of the fiber, and the change in the value is recorded. , which changes in a wavy manner in the length direction, is a value defined as the ratio between the practical maximum value and minimum value.

Hereinafter, the method for producing the fiber with sharpened ends according to the present invention will be explained in more detail.

In the present invention, polyester synthetic fibers are:
It refers to aromatic polyesters such as polyethylene terephthalate and polyhexylene terephthalate, and copolymers mainly composed of these, and also includes those blended with various additives such as conventionally known matting agents and antistatic agents.

In the present invention, the thick fibers are typically produced using the thick fibers described in JP-A-54-160841, or by the method described in the same publication, that is, by constantly discharging a molten polyester polymer material from a mouth hole. Extruding at a speed, guiding the extruded yarn through a gap of 6 mm or less into a cooling bath, and after passing through the cooling bath, bringing it into contact with a vibrating body to give periodic yarn speed changes,
The yarn speed change is transmitted to the extruded yarn in a flowing state, and the yarn is then taken up by a take-off roller that rotates at a constant speed, and then the extruded yarn has a circumferential speed greater than the circumferential speed of the take-up roller. Thick and fine fiber yarns that are actually obtained by stretching with a drawing roller are preferably used, and in particular, according to the findings of the present inventors, in order to obtain a good shape of fibers with sharpened ends at a high yield, thick and fine fibers are preferably used. It is preferable to use the above-mentioned thick and thin fibers having a fineness ratio of 10 or more. By using a continuous yarn having a particularly large thick-to-fine ratio as the yarn to be treated, it becomes possible to divide the continuous yarn at the thin portion, and the divided ends can be subjected to the sharpening treatment. It is something that becomes.

In addition, as a hydrolyzing agent for polyester synthetic fiber in the present invention, an alkaline compound is used,
Preferably, sodium hydroxide and potassium hydroxide are used. As the medium, water or a mixture of water and an organic solvent such as an alcohol is used. Moreover, amines such as ethanolamine and pyridine can be used in combination with these processing solutions. Further, known hydrolysis accelerators such as laurylcipendylammonium chloride and cetyltrimethylammonium chloride can also be used in combination. Furthermore, activators, softeners, and even swelling agents can be added. In particular, when a surfactant that can withstand hydrolysis conditions, such as a fluorine-based surfactant, is added, a better sharp edge can be obtained.

In the present invention, in order to obtain a good shape of fibers with sharpened ends at a high yield, in addition to using thick and thin fibers with a large thick-to-thin ratio as described above, treatment conditions suitable for each case must be adopted. It is also important. That is, it is necessary to appropriately select optimal processing conditions depending on the fiber material, average thickness, etc. As an example,
According to the findings of the present inventors, when using a sodium hydroxide solution, the concentration is usually 10-40% and the temperature is 80%.
The treatment can be carried out satisfactorily at a temperature of ~130°C for a time of 5 to 120 minutes. In addition, treatment that is stronger than necessary is generally undesirable because it increases the amount of decomposition and impairs the yield.

As described above, the method of the present invention has the advantage that fibers having extremely well-shaped tapers at both ends can be produced in large quantities at low cost through one-step processing without the need for any special equipment.

The double-end sharpened fiber obtained by the present invention has a point-like gentle taper at the tip, so it is extremely flexible and resembles animal hair.
In addition to applications such as brushes and brushes, it can also be applied to raised fabrics that aim to have the look of high-quality angora or mink fur.

EXAMPLES Hereinafter, the method for producing a fiber with sharpened ends of the present invention will be specifically explained with reference to Examples.

Example 1 Polybutylene terephthalate fibers made by the method described in JP-A-54-160841, with an average fineness of 40 denier, a thick-to-fine ratio of 12, and a thick-to-fine period of 50 mm, were placed in a skein, and the skein was soaked with 40% NaOH. , placed in a 120°C bath and treated for 10 minutes. After treatment, decomposition products were removed by thorough washing with water. The obtained short fiber had a good taper shape with dotted tips at both ends and a gentle slope.

Example 2 A thick polyethylene terephthalate fiber having an average fineness of 35 denier, a thick-to-fine ratio of 12, and a thick-to-fine period of 40 mm was taken into a skein by the method described in JP-A-54-160841, and the skein was soaked in 20% NaOH. ,110℃
bath and treated for 10 minutes. After treatment, decomposition products were removed by thorough washing with water. The tapered shape of the obtained short fibers had a good taper with dotted tips at both ends and a gentle slope.

Example 3 Polybutylene terephthalate fibers with an average fineness of 50 denier, a thick/fine ratio of 16, and a thick/fine period of 55 mm were taken into a skein by the method described in JP-A No. 54-160841, and were mixed with 40% NaOH and 120 denier. It was placed in a bath at ℃ and treated for 15 minutes. After treatment, decomposition products were removed by thorough washing with water. The resulting short fibers had a very good tapered shape with dotted tips at both ends and a gentle slope.

Claims (1)

[Claims] 1 A yarn consisting of continuous fibers made of polyester fibers and having thick and thin parts periodically in the longitudinal direction of the fibers and having a thick-to-thin ratio of 4 or more and 50 or less is treated with a hydrolyzing agent. A double-end sharpened fiber characterized in that the continuous yarn is split at the thin portion and the split end is sharpened by immersing the fiber in a treatment solution containing the fiber and treating the fiber under hydrolysis conditions. manufacturing method.