JPS63112769A - Polyester staple fiber - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applied to the field of spun yarns and nonwoven fabrics that require particularly soft texture, and has good card (carding machine) passability. This invention relates to short polyester fibers suitable for producing high-quality clothing.

[Prior art] Polyester short fibers are opened into short fibers through a carding process to form a thin sheet-like garment that is intertwined with each other.This garment is applied in the field of non-woven fabrics, or this garment is made into a sliver. After passing through a filament machine, roving frame, and spinning machine, it is made into a spun yarn, which is then applied to woven and knitted fabrics.

In recent years, in these fields, there has been a demand for fabrics with a soft texture, and this has been addressed by reducing the denier of single yarns. However, reducing the single yarn denier increases troubles in the carding process and prevents high-quality garments from being obtained with high productivity, so various countermeasures have been taken. That is, the main countermeasures include improving the crimp performance, shortening the fiber length, and applying an oil agent with good smoothness.

By the way, it is well known that when the single yarn denier becomes smaller, the crimp performance decreases and the card passing property deteriorates.
In order to improve this, we can reduce the denier of tow supplied to the crimper, or slow down the crimper speed and increase the residence time in the steam preheating box just before the crimper, increasing the temperature of the tow. is taking. However, these methods have drawbacks such as poor process performance and low production capacity, so there are limits to their ability to produce sufficient effects.

Generally, in order to improve card passing properties, it is empirically determined that the ratio of fiber length and single yarn (herein meant single thread) denier is set below a certain value (for example, fiber length/denier - 1.5 inches/1.5 inches). 5 denier = 1 or less). However, if the denier is reduced to 1.0 denier or less without taking any special measures to improve the crimp performance, it is necessary to extremely shorten the fiber length in order to improve the card passability. As described above, when the fiber length becomes short, the entanglement of the carded web becomes small, which is not preferable in terms of handling.

In addition, applying an oil agent with good smoothness is known as another means for improving card passage performance. As the oil agent used for polyester staple fibers, alkyl phosphate esters (salts) are often used as the main component. However, when the single yarn denier is 1.0 denier or less, it is currently impossible to satisfy the card passability even if these oils are used.

[Object of the Invention] An object of the present invention is to provide short polyester fibers with good card passing properties that solve the problems peculiar to such a small denier and make it possible to obtain a high-quality carded web with high efficiency. There is a particular thing.

[Structure of the Invention] As a result of intensive research aimed at achieving the above object, the present inventors used an oil under specific conditions with a small coefficient of friction, and at the same time optimized the denier, fiber length, and crimp performance. As a result, the desired short fibers were obtained.

That is, the present invention has a single yarn denier of 1.0 denier or less, a fiber length of 25 mm or more and 40 mm or less, a crimp count of 11 or more and 15 or less per 5 mm, and a crimp degree of 10% or more and 1
4% or less, ratio of degree of crimp to number of crimp is 0.75 or more1
．． 15 or less and has a linear or branched carbon number of 8 or more and 18 or less, 60 to 95% by weight of an alkyl phosphate potassium salt, and a viscosity at 25°C of 1.0
This polyester short fiber is characterized by being coated with an oil agent containing 2 to 25% by weight of silicones having a diameter of 0.00 centistoke or more, and the remainder mainly consisting of a nonionic activator.

To specifically explain the present invention, first, the linear or branched alkyl group of the alkyl phosphate potassium salt of the present invention has 8 to 18 carbon atoms, and the salt has 60 to 95 carbon atoms in the total oil agent. % by weight, preferably 70-90% by weight.

If the number of carbon atoms in the salt is less than 8, the coefficient of friction will increase and the winding property on the card will increase.If the number of carbon atoms in the salt is less than 8, the windability on the card will increase. This is undesirable as it increases curling. The alkyl group is particularly preferably one derived from a linear monohydric alcohol and having 12 to 18 carbon atoms. Further, if the ratio of the salt is 60i1% unvortexed, the smoothness will be insufficient unless a large amount of silicone is used, and the antistatic property will also be insufficient. Moreover, if it exceeds 95% by weight, the proportion of silicone decreases, and no effect of lowering the coefficient of friction can be expected.

The silicone used in the present invention has a viscosity at 25° C. of 1,000 centistokes or more, preferably 10,000 tonnes stokes.

If it is less than 1.000 centistokes, the effect of lowering the coefficient of friction is insufficient. And the ratio of this silicone is 2
~25% by weight. If this ratio is less than 2% by weight, the effect of reducing the coefficient of friction will be insufficient, and if it exceeds 25% by weight, the antistatic properties will be insufficient. The silicones used individually include dimethylpolysiloxane and various modified silicones such as epoxy-modified, amine-modified and polyether-modified silicones, with dimethylpolysiloxane being particularly preferred.

Generally, it is difficult to obtain an emulsion in which silicone itself is uniformly mixed with other ingredients, but in the present invention, by using emulsion polymerization type silicone that has been developed in recent years, it has been possible to obtain a uniform and highly concentrated emulsion. It turns out that it is possible to obtain.

Next, the main oil components other than alkyl phosphate potassium salt and silicone are a nonionic surfactant used for emulsifying silicone and a nonionic surfactant as a convergence modifier. Occasionally, smoothing agents other than surfactants such as mineral oil and fatty acid esters may also be used.

On the other hand, regarding the crimp performance of short fibers, the degree of crimp (CD, %
), the number of crimps (CN, peak/25mm), and the ratio of the degree of crimps to the number of crimps (CD/CN) are related, and 0.75≦CD10N
≦1.15.10≦CD≦14. and 11≦CN≦15
is necessary. CD/CN exceeds 1.15 and C
In order to obtain short fibers with D exceeding 14, it is possible to make the total denier of the tow to be drawn extremely small or to make the crimper speed extremely slow, but this will slow down the process and production capacity. This is not desirable. On the other hand, CD/CN is less than 0.75, and even CD is 10
If the amount is less than that, the amount of cotton sinking into the cylinder will increase and eventually it will wind up, resulting in an increase in neps, forcing the operation to reduce card supply and extremely reduce productivity. Moreover, when CN exceeds 158, short fibers become entangled with each other, resulting in a significant increase in neps, and when ON is less than 11, winding around the cylinder increases, which is not preferable.

Furthermore, the single fiber denier of such short fibers needs to be 1.0 denier or less. In other words, when the denier exceeds 1.0 denier, both the crimp performance and the bending rigidity increase, so there is almost no difference between the normal oil agent and this oil agent.

In addition, the lower limit is preferably about 0.56e; if it is less than this, the crimp performance will decrease to a large IJ, and the bending rigidity will also decrease due to the fine denier, even if treated with the above oil agent. , it becomes impossible to obtain sufficient quality. Further, the fiber length is 25 mm or more and 40 ml or less. If it is less than 25 mm, the entanglement between the fibers is insufficient,
It is difficult to form a web with a card, and it breaks even with the slightest force, which is undesirable. Moreover, if it exceeds 40 mm, the card will sink more into a part of the cylinder, and the card will become more sticky, making it impossible to achieve the desired goal.

When the compounded oils regulated here are processed by the immersion method, which is usually adopted as an aqueous emulsion,
It is usually appropriate to use it as an emulsion with a concentration of 0.5 to 5% by weight. However, it can also be treated by a roller contact method or a spray method, and is not particularly limited by the treatment method. Further, the oil agent of the present invention can be applied to polyester fibers at any step of manufacturing the polyester fibers. Further, after applying the oil agent in the form of a tow by a dipping method, the treated fibers are subjected to a dry heat treatment,
After that, it is also possible to re-lubricate again by spraying.

In the present invention, polyester mainly refers to polyethylene terephthalate. In addition, with regard to spun yarn, the desired goal can be achieved not only when using 100% polyester, but also when blending it with cotton or rayon.

[Operations and Effects of the Invention] As described above, single yarn de of 1.0 denier or less and 2
Polyester short fibers with a fiber length of 5 to 40 mm and crimping performance that can be imparted under normal conditions do not get curled with cards, making it possible to obtain high-quality clothing with high productivity. Make it.

[Examples] Next, the present invention will be specifically explained with reference to Examples, but of course the present invention is not limited to these Examples.

Example 1 The intrinsic viscosity measured with an orthochlorophenol solution was 0.
65 drawn polyester fiber (single denier 0.
8 denier) was soaked in a tow state in an aqueous solution of the oil shown in the table below, and crimped at the same time as it was squeezed with a crimper so that the amount of oil applied was 0.15% by weight. /
CN=12/13 was obtained. Next, the raw cotton was subjected to a dry heat treatment at 120'C for 30 minutes, cut into 38 mm lengths, opened in a conventional manner, and then passed through a card to obtain the results shown in the following table.

Here, the raw polyester cotton to be supplied to the card is a wrap with a thickness of 12 ounces/yard, and a
ppm, cylinder 25Orpm, Dotufa-15
The conditions were to obtain a sliver of 400 gels/6 yards at rpm.

For the alkyl phosphate potassium salt, a linear alkyl group with a different number of carbon atoms was used. The silicone used was Dimedyl type emulsion polymerized silicone whose viscosity was changed as shown in the following table. Components other than silicone for alkyl phosphate include nonionic surfactants, including emulsifiers used in emulsion polymerization.
And so.

As a nonion, polyethylene glycol (molecule f
f11000-2000) mono-dipalmitate.

and mono-distearate, polyoxyethylene addition (
Nonylphenol ether (number of added moles: 5 to 40) and polyoxyethylene-added hydrogenated castor oil ether (number of added moles: 6 to 12) were used.

The friction coefficient of the single fiber was measured by the radar method. The speed was 18 m/min, and the load was 100 mg. (20'
C.

65%R]1).

For the card, the static electricity of the wear that came out of the doffer was measured using a Kasuga static electricity meter.

Also, during normal operation, the card was stopped and the number of large nep in the web between the docker and the calender roller was counted. The degree of winding (J) was determined by directly observing the amount of winding on the cylinder by opening the lid from time to time (25°
CX60%RH).

From Table 1, it can be seen that the oil agent plasticity of the present invention exhibits excellent card passability and wear quality.

Example 2 In the oil agent B of Example 1, the single yarn denier of polyester is ! Evaluation was conducted by changing the tit4ft length and crimp performance as shown in Table 2.

From Table 2, it can be seen that the raw cotton having the performance range of the present invention has excellent card passability and web quality, and has good productivity.

The web of Example M had weak tangles and was easily torn apart, making it difficult to handle the web after the card, which was a work limit.

Claims (1)

[Claims] Single yarn denier is 1.0 denier or less, fiber length is 25 m
m or more and 40 mm or less, the number of crimps per 25 mm is 11 or more and 15 or less, the crimp degree is 10% or more and 14% or less, and the ratio of the crimp degree to the number of crimp is 0.75 or more and 1.15 or less. , and 60 to 95% by weight of an alkyl phosphate potassium salt having a straight chain or branched carbon number of 8 or more and 18 or less
A short polyester fiber comprising: 2 to 25% by weight of a silicone having a viscosity of 1,000 centistokes or more at 25°C, and an oil agent with the remainder mainly consisting of a nonionic activator.