JPH0754269A - Polyester short fiber for spun yarn - Google Patents

Abstract

PURPOSE:To obtain a polyester short fiber spinnable in excellent operability while preventing the causing scum by applying a lubricant having a specific composition to a specific polyester short fiber for spinning. CONSTITUTION:This polyester short fiber for spinning is produced by drawing and crimping a polyester fiber tow containing >=1wt.% of titanium dioxide to obtain a tow having a single fiber fineness of >=0.5 de, coating the obtained tow with 0.1-0.4% owf of a lubricant composed of (A) 30-50wt.% of a polyoxyethylene or polyoxypropylene alkyl ether (the carbon number of the alkyl group is 8-20 and the addition molar number of the oxy-unit is 2-17), (B) 20-40wt.% of a potassium alkylphosphate (the carbon number of the alkyl group is 12-18), (C) 10-30wt.% of a 18-35C fatty acid ester, (D) 10-20wt.% of a cationic surfactant and (E) 5-20wt.% of a polysiloxane, cutting the coated tow into short fibers and passing through a spinning process. The fiber coated with the lubricant can b spun in high operability over a long period of time in each spinning step without causing scum.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyester short fiber for spun yarn containing titanium dioxide having excellent spinnability.

[0002]

2. Description of the Related Art Generally, polyester, especially polyethylene terephthalate, has excellent mechanical and chemical properties and is widely used as a fiber for clothing. Add a pigment such as titanium to improve the appearance and texture,
Processing such as spinning is performed.

However, when the amount of titanium dioxide contained in the fiber is increased, deposits (hereinafter referred to as scum) are deposited on metal parts and roller parts in each spinning process, resulting in coil disorder and yarn breakage. Occurs, which causes deterioration of operability and deterioration of quality.

This is because as the amount of titanium dioxide contained in the fiber increases, the particles of titanium dioxide exposed on the surface of the fiber also increase, and the exposed particles rub against the metal part and the resin part during spinning. It is recognized that, due to this, the fibers fall off from the fiber surface and are accumulated as scum on the yarn paths of guides, coilers or flyers, and the spinning condition is deteriorated.

Conventionally, it has been unavoidable that such a phenomenon will occur, but as a solution to such a drawback, the present applicant has previously mentioned (a) and (c) above.
Proposed is a staple fiber for spun yarn which imparts an oil agent having a specific composition consisting of the components (e) to (e) (JP-A-4-241169).
Although these short fibers were able to reduce scum accumulation and improve the spinnability, the scum accumulation and roller wrapping were not sufficiently satisfactory in long-term continuous operation.

[0006]

In view of the above situation, the present invention further solves the above-mentioned drawbacks, prevents scum from occurring in the spinning process even during continuous operation for a long time, and spins with good operability. It is intended to provide a polyester short fiber for spun yarn which can be manufactured.

[0007]

The present invention solves this problem, and its gist is as follows. A polyester short fiber for spun yarn, containing 1% by weight or more of titanium dioxide and having a fineness of 0.5 denier or more, wherein 0.1 to 0.4% by weight of an oil agent having the following composition is added to the fiber. Polyester staple fiber for spun yarn. (a) Polyoxyethylene or polyoxypropylene alkyl ether (provided that the alkyl group has 8 to 20 carbon atoms and the ethylene oxide or propylene oxide has 2 to 17 moles added) 30 to 50% by weight (b) Alkyl phosphate potassium salt (However, 12 to 18 carbon atoms in the alkyl group) 20 to 40 wt% (c) Fatty acid ester having 18 to 35 carbon atoms 10 to 30 wt% (d) Cationic surfactant 10 to 20 wt% (e) Polysiloxane 5-20% by weight

The present invention will be described in detail below. First, the polyester short fiber for spun yarn in the present invention has a single fiber fineness of 0.5 denier or more and contains titanium dioxide in an amount of 1% by weight or more. Even if the single fiber fineness is 0.5 denier or more, if the content of titanium dioxide is less than 1% by weight, addition of a commonly used oil agent will not deteriorate the operability due to scum accumulation due to titanium dioxide particles. Absent.

The amount of the oil agent attached is 0.1 with respect to the fiber.
It is necessary to set it to ~ 0.4% by weight. If the amount is less than 0.1% by weight, scum is undesirably accumulated on the yarn path of the guide, coiler or flyer during spinning, especially in the case of drawing or roving. Is generated, or winding around the roller occurs during drawing, roving or spinning, which is not preferable because the spinning property is deteriorated.

Next, the oil agents applied to the fibers are (a) to (e)
It is necessary that the above components are blended in a specific ratio.

The component (a) is polyoxyethylene (PO
E) or polyoxypropylene (POP) alkyl ether (provided that the alkyl group has 8 to 20 carbon atoms and the added mole number of ethylene oxide or propylene oxide is 2 to 17), and mainly has the action of enhancing the sizing properties of the short fibers. It is necessary to add 30 to 50% by weight of this.

In this compound, if the number of carbon atoms of the alkyl group is less than 8, it becomes impossible to maintain the sizing property of the fiber, and if the number of carbon atoms exceeds 20, the viscosity becomes high, which causes wrapping and is not suitable. Further, if the number of added moles of ethylene oxide or propylene oxide is less than 2, there is no effect of concentrating the fibers, and if the number of added moles exceeds 17, the viscosity becomes high and the smoothness deteriorates, which is not preferable.

Further, if the compounding amount of this compound is less than 30% by weight, the focusing property is deteriorated, causing wrapping and increasing scum accumulation. The friction coefficient becomes too high, which results in poor quality of the product such as mixed cotton, card opening failure, and draft spots after the kneading.

Specific examples of the compound as the component (a) include PO
E lauryl ether, POE oleyl ether, POE
Octyl ether, POE stearyl ether, POP
Examples include nonyl ether and the like.

The component (b) is an alkyl phosphate potassium salt having 12 to 18 carbon atoms, which mainly acts to lower the friction coefficient with respect to metal, and it is necessary to add 20 to 40% by weight of this salt. There is.

If the carbon number of this compound is less than 12, the friction coefficient with respect to the metal becomes high and scum easily occurs. If the carbon number exceeds 18, rolling of the roller easily occurs, which is not preferable.

Further, if the compounding amount of this compound is less than 20% by weight, the friction coefficient with respect to the metal becomes high, and there is almost no effect of preventing scum accumulation, and conversely if it exceeds 40% by weight.
As a result, the action of the compound of the component (a) or the component (c) is impaired, the converging property between fibers and the oil film strength are weakened, and it is not preferable because it causes winding of the roller.

Specific examples of the compound as the component (b) include octyl phosphate potassium salt, lauryl phosphate potassium salt, stearyl phosphate potassium salt and the like.

The component (c) is a fatty acid ester having 18 to 35 carbon atoms, which mainly acts to increase the strength of the oil film, and it is necessary to add 10 to 30% by weight of this.

If the number of carbon atoms of this compound is less than 18, the oil film is weak and scum easily occurs, and if the number of carbon atoms exceeds 35, the viscosity is high and roller winding occurs, which is not preferable.

Further, if the compounding amount of this compound is less than 10% by weight, there is almost no effect of preventing scum accumulation, and conversely, if it exceeds 30% by weight, the action of the compound of component (a) or component (b) is exerted. This is not preferable because it results in a deterioration of the bundling property between the fibers and a high friction coefficient with respect to metal, which causes roller winding and scum generation.

Specific examples of the compound as the component (c) include octyl stearate, isotridecyl stearate, and PO.
E lauric acid ester etc. are mentioned.

The cationic surfactant as the component (d) mainly acts to prevent the generation of static electricity.
It is necessary to add 20% by weight. If the blending amount is less than 10% by weight, the effect of suppressing static electricity cannot be obtained, and roller wrapping occurs due to static electricity generation, which causes yarn breakage, which is not preferable. On the other hand, if it exceeds 20% by weight, the action of other components is impaired, and scum accumulation and roller winding occur, which is not preferable.

Examples of the compound of the component (d) include quaternary ammonium salt type, amide type, sulfonium type and phosphonium type cationic surfactants.

The component (e) polysiloxane reduces the loss of the oil agent from the fiber, and the component (a) ether compound,
It acts to further promote the action of the alkyl phosphate compound of component (b) or the ester compound of component (c), and in particular, due to the synergistic effect with the alkyl phosphate potassium salt of component (b), the focusing property between short fibers is improved. While increasing
It lowers the coefficient of friction against metal.
It is necessary to blend up to 20% by weight. This blending amount is 5% by weight
If it is less than the above range, the effect of preventing the oil agent from falling off from the fiber is insufficient, and the effect of the oil agent, especially the effect of the component (b) cannot be fully exerted. Conversely, if it exceeds 20% by weight, the viscosity increases. On the contrary, winding around the roller may occur, causing yarn breakage, which is not preferable.

Specific examples of the component (e) include dimethylpolysiloxane and methylphenylpolysiloxane as non-reactive types, and dimethylpolysiloxanediol, methylphenylpolysiloxanediol and methylhydrogenpolysiloxane as reactive types. However, dimethylpolysiloxane is preferably used.

The blended oil agent used in the present invention improves the spinnability of polyester short fibers for spun yarn, which contains titanium dioxide in an amount of 1% by weight or more in the short fibers. But,
When the components (a) to (e) are used in combination, good results are not obtained at any mixing ratio, and the effects are exhibited only when the components are mixed so as to have the above composition.

In the present invention, as the polyester,
Examples thereof include polyethylene terephthalate, polybutylene terephthalate, and a copolyester mainly composed of these and copolymerized with isophthalic acid, 5-sodium sulfoisophthalic acid, diethylene glycol, neopentyl glycol and the like.

The polyester short fibers for spun yarn are melt-spun of these polyesters containing 1% by weight or more of titanium dioxide by a conventional method, and the resulting unstretched fibers are bundled into a desired thickness and subjected to a stretching step, It is manufactured by cutting to an arbitrary length through a crimping step.

The oil agent in the present invention can be applied at any stage of these steps, but is preferably applied after completion of stretching and before crimping or after crimping and before cutting. This is because it is necessary to consider the stretching operability and the heat resistance such as the alteration of the oil agent after the heat setting step after stretching.

[0031]

When the amount of titanium dioxide contained in the fiber exceeds 1% by weight, a large amount of titanium dioxide particles are exposed on the surface of the fiber, and the exposed particles are rubbed against the metal portion or the resin portion during spinning. This makes it easier to fall off the fiber surface,
This is a cause of scum accumulation on guides, rollers and coilers for drawing, rollers and flyer yarn paths for roving, and rollers for spinning, which is a cause of deterioration of spinnability.

In the spinning process using the polyester short fiber for spun yarn containing titanium dioxide of 1% by weight or more of the present invention, the reason why scum does not deposit on the yarn paths of guides, coilers or flyers, etc., is for the reason. It is not always clear, but it is speculated as follows.

By adding the oil agent having the above composition, the short fiber converging property is improved, the oil film strength is increased, and the coefficient of friction with the metal or resin portion is reduced, especially for a tube or a coiler in a draft. It is presumed that the accumulation of the scum and the accumulation of the scum on the flyer yarn path in the roving are prevented and the spinning property is improved.

In short, according to the present invention, the synergistic effect of each component of the oil agent, particularly the synergistic effect of the alkyl phosphate potassium salt and the polysiloxane, improves the focusing property between the short fibers and further reduces the friction coefficient with respect to the metal. As a result, it is presumed that titanium dioxide is prevented from falling off from the fiber surface and scum accumulation is prevented in the spinning process.

[0035]

EXAMPLES Next, the present invention will be specifically described by way of examples. The measurement and evaluation in the examples were carried out by the following methods. (A) Oil agent adhesion amount (OPU) The oil agent was extracted from the fiber with n-heptane, and n-heptane was evaporated to dryness, and the weight was measured and calculated. (B) Convergence property Comparison was made based on the size of the wrap diameter (cm / 8kg). (C) A fiber having a scum generation rate of 200 kg in the spinning process was passed through the kneading process, and the deposits on the rubber roller, the metal roller, the tube and the coiler were collected, weighed and compared. (D) Coiling form The shape of the sliver that had undergone the drawing process was visually determined. (E) Rolling around the roller The number of windings around the drawing roller at 25 ° C. and 65% RH was compared.

Example 1 Polyethylene terephthalate fibers containing 3.0% by weight of titanium dioxide were bundled into a tow of 150,000 denier, and after stretching,
Mechanical crimping was applied to obtain a tow (crimp tow) having a monofilament fineness of 1.0 denier. The oil agent (normal temperature) shown in the example of Table 1 was applied to this crimp tow so as to be 0.22% by weight based on the fiber, and the fiber cut to 38 mm was aged overnight at 25 ° C. and relative humidity of 65% RH. Table 3 shows the results of measuring the bundling property, the spinning scum, and the coiling foam after passing through the steps of kneading cotton, curd, and kneading after adjusting to equilibrium water content. Regarding the converging property and wrapping, the wrap diameter and the number of times of wrapping were compared, and the scum and coiling foam obtained good results were marked with ⊚, and in the following, they were defective in the order of ○, △, ×. Qualitatively shown.

Examples 2 to 6 Table 3 shows the results obtained in the same manner as in Example 1 except that the composition and amount of the oil agent applied to crimptow were changed as shown in Table 1.

Example 7 Example 1 was repeated except that the composition of the oil agent added to the crimp toe obtained from polyethylene terephthalate fiber containing 1.0% by weight of titanium dioxide in the same manner as in Example 1 was changed as shown in Table 1. Results obtained in the same manner as in Table 3 are shown in Table 3.

Comparative Examples 1 to 7 Table 3 shows the results obtained in the same manner as in Example 1 except that the composition and amount of the oil agent applied to crimptow were changed as shown in Table 2.

Reference Example Polyethylene terephthalate fibers containing 0.5% by weight of titanium dioxide were bundled into a tow of 150,000 denier, and after stretching,
Table 3 shows the results obtained in the same manner as in Example 1 except that mechanical crimped crimp tow having a single fiber fineness of 1.0 denier was changed in composition and amount of the oil agent to be applied as shown in Table 2.

[0041]

[Table 1]

[0042]

[Table 2]

In Tables 1 and 2, the symbols of the oil agent components mean the following compounds, and the number in parentheses () indicates the number of moles of ethylene oxide or propylene oxide added. A ₁ : POE (8) lauryl ether A ₂ : POE (8) oleyl ether A ₃ : POP (10) nonyl ether B ₁ : Lauryl phosphate K salt B ₂ : Stearyl phosphate K salt C ₁ : Octyl stearate C ₂ : Isotridecyl stearate D: Stearyl amide ethosulfate of dimethylaminopropylamine (amide type cationic surfactant) E: Dimethylpolysiloxane F: POE (10) castor oil ether

[0044]

[Table 3]

As is clear from the results of Table 3, in the examples satisfying the requirements of the present invention, there was no generation of spinning scum,
It had good sizing properties, coiling foam, no winding, and good spinning properties. On the other hand, even in the oil agent composition of the present invention shown in Comparative Examples, when the blending ratio is not satisfied or when the OPU is low or high, scum is generated, coiling foam is deteriorated, and wrapping occurs in a card or a strip, In the conventional oil agent composition shown in Comparative Example 7, the spinnability as a whole was poor. However, as shown in the reference example, if the content of titanium dioxide was less than 1% by weight, there was no problem in spinnability.

[0046]

According to the present invention, a polyester short fiber for a spun yarn containing 1% by weight or more of titanium dioxide and having a single fiber fineness of 0.5 denier or more can prevent scum from occurring in the spinning process and can be used for a long period of time. Provided is a polyester short fiber for spun yarn, which can be spun with good operability.

Claims (1)

[Claims] 1. A polyester short fiber for spun yarn, containing 1% by weight or more of titanium dioxide and having a single fiber fineness of 0.5 denier or more, wherein an oil agent having the following composition is 0.1 to 0.1% based on the fiber.
0.4% by weight of polyester staple fiber for spun yarn. (a) Polyoxyethylene or polyoxypropylene alkyl ether (provided that the alkyl group has 8 to 20 carbon atoms and the ethylene oxide or propylene oxide has 2 to 17 moles added) 30 to 50% by weight (b) Alkyl phosphate potassium salt (However, 12 to 18 carbon atoms in the alkyl group) 20 to 40 wt% (c) Fatty acid ester having 18 to 35 carbon atoms 10 to 30 wt% (d) Cationic surfactant 10 to 20 wt% (e) Polysiloxane 5-20% by weight