JPS5853083B2 - Special composite fiber and its manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a special composite fiber that has complex irregularities on its surface and minute cavities near the fiber surface.

More specifically, using two types of polymers A and B, a (A+B) component, which is a blend component of the A and B components, is created in a spinneret, and a composite fiber of the (A+B) component, A component, and B component is made, and then, The present invention relates to a conjugate fiber with excellent fiber texture obtained by extracting component B from the surface of the fiber and a portion slightly inside the fiber using a good solvent thereof, and a method for producing the same.

Efforts have been made to bring the texture and physical properties of synthetic fibers closer to those of natural fibers.

However, it has not yet achieved sufficient effects.

The reason for this is that natural fibers have extremely precise cross sections, surface conditions, component compositions, materials, etc., and it is said that it is impossible to satisfy all of these requirements industrially.

However, synthetic fibers have been modified by improving some aspects by emphasizing certain parts.

The present invention relates to a special conjugate fiber and a method for producing the same, which were discovered in an effort to eliminate more drawbacks at the same time.

That is, in terms of morphology, the composite fiber of the present invention has complicated grooves randomly existing in various sizes on the surface, and minute cavities exist slightly inside the surface. It is a composite fiber, and the remainder contains A, B, (A-
1-B) is a three-component composite fiber, (A+B) If
By using a mixed component called f, it is possible to bond the two components A and B, and to adjust the suppleness and texture of the yarn, which could not be achieved with a concentric sheath-core.

The most important feature of the present invention is the complicated missing grooves and minute cavities of various sizes that are generated after extracting the B component existing on and near the surface.

The missing grooves on the surface create a texture similar to the scale of natural fibers, giving it a moist and calming luster.

On the other hand, the residual ratio of A, B1ff, and the mixed components (
A+B) The ratio of the remaining amount to A and Bff, and (A+B)
) It is easy to adjust the elasticity, strength, elongation, etc. of the fiber by adjusting the ratio of amounts of A and B in the residue, and to make the physical properties closer to your preference or those of natural fibers.

That is, one invention related to the present application is a composite fiber having a three-layer structure using two types of polymers A and B having different solvent solubility, the substantial structure of which is (a) a part of component B or an epidermis layer consisting essentially only of component A, in which complex grooves and minute cavities created by the extraction of the majority exist randomly and in various sizes, and (b) the inside of the epidermis layer. Following this, a rich and homogeneous intermediate layer consisting only of component A, which exists in a form that envelops the innermost layer,
and (/'9 A uniform component consisting of the same residue (B component) as the above-mentioned extracted residue existing in a concentric or eccentric form as a core component.
It is a special composite fiber characterized by being taken over by three innermost layers of high quality. Another invention is to use two extruders to extrude separately and have different solvent solubility. A to do
, a part of each of the polymer streams of component B2 is introduced into a mixing and stirring zone with obstacles installed inside the spinneret, and mixed with ferric acid to form a mixed stream (A-4-B) component and the above-mentioned. Germany-Germany A
, B components are combined to form a composite fiber precursor consisting of three layers of (A+B):A:B in which the (A+B) component occupies the outermost layer, and then a part of the B component is obtained from the outermost layer of the composite fiber. Alternatively, a method for producing a special composite fiber having fine irregularities on the surface and minute cavities near the surface, characterized in that most of the fiber is extracted with a solvent.

A typical fiber form of the present invention is shown in FIG. 3 (in the figure, dotted lines represent virtual boundaries).

In Figure 3, you can see the missing streaks (like holes) on the fiber surface.
Grooves) are traces where the B component was extracted from the (A+B) residue using a solvent, and have a complex shape and various sizes.

These shapes and sizes are A in the (A+B) component:
It can be changed depending on the amount ratio of B and the mixing condition.

This surface portion, that is, the epidermal layer, is substantially made only of component A, since most of component B is extracted with a solvent.

Further, in the epidermal layer, a large number of minute cavities exist because a part or most of the B component has been extracted from the (A+B) component.

The degree of formation of the cavities can be controlled by the degree of the extraction process, but there is a tendency for the amount of residual component B to increase toward the inside of the fiber.

However, if enough time is spent, all of the B component can be extracted.

Following the skin layer is an intermediate layer, which is normally a single layer of polymer consisting of a single A component.

In the claims, the term "substantial homogeneity" is used to specify that there are no cavities or missing parts such as the epidermal layer.

This intermediate layer prevents the extraction and swelling of polymer B, which is a core component, and contributes to ensuring the mechanical properties of the fiber, such as strength and elongation, and initial Young's modulus.

The fiber of the present invention uses polymers of two components A and B, which have different solvent solubility, and is extruded with a twin-screw extruder.
A mixed flow of part of A and B polymers in the spinneret (A+B)
The (A+B) component and the three precepts of both A and B are combined to form an arrangement of the (A+B) residue on the fiber surface, then the A component in the middle layer, and the B component outside the core. It can be obtained by once forming a conjugate fiber having a three-layer structure, and then extracting component B with a solvent.

Therefore, it is possible to significantly improve the surface texture due to the grooves generated after extracting the B component from the surface, and at the same time, it is possible to design the mechanical properties to suit the purpose and use depending on the ratio of the A and B components and the shape.

In particular, the ratio of the amount of B component extracted to the amount of B component remaining in the core component,
The thickness of component A in the intermediate layer plays a major role in designing mechanical properties.

The knitted fabric made from the fiber of the present invention has a feel and texture that is similar to that of cotton.
It is extremely similar to natural fibers such as linen and wool, and has a calm and reflective shine, making it a product never seen before.

This is considered to be an effect of random missing grooves of various sizes existing on the surface.

Furthermore, the fibers of the present invention have excellent water absorption and sweat absorption properties, and this is thought to be due to the presence of minute cavities.

An example of the method for producing the fiber of the present invention will be described below.

That is, A, (A+B) with a 3-axis extruder.

The three components of B may be extruded separately to make a conventionally known three-layer sheath-core type composite fiber, and then the B component may be extracted, but in this case, the missing grooves on the surface after extraction of the B component are small. This is not preferable because the discharge amount of the components A, B, and (A+B) becomes too small, and the residence time until discharge becomes longer, resulting in deterioration and yellowing.

Therefore, to produce the fiber of the present invention, a twin-screw extruder is used to extrude the two-component polymers A and B, and a portion of the A and B components are placed in a mixing and agitating zone with obstacles installed inside the spinneret. A preferred method is to form a mixed flow component of (A+B) by guiding and self-stirring, and to combine the (A+B) component with the individual components A and B.

The first advantage of having a mixing and stirring zone inside the spinneret is that different types of polymers can be mixed just before discharge. This has the great advantage of suppressing reactions as much as possible.

The second point is that it is easy to mix substances with different melting points.

In conventional methods, it is known that in such cases, the chips stick together during spinning injection, resulting in poor biting.

However, when mixing and stirring in a spinneret, components A and B are incorporated under optimal conditions, so such trouble does not occur.

Furthermore, the third point is that when mixing is performed in the mixing and stirring zone inside the spinneret, the degree of mixing and stirring can be freely selected depending on the length of the mixing zone and the efficiency of the mixing element, regardless of the rotation speed of the extrusion screw. .

This means that it is possible to design the properties of the composite fiber to be manufactured down to a very fine point, and it can be said to be an extremely effective method for improving stiffness, texture, etc.

In any case, the present invention is a special composite fiber in which the surface layer has missing grooves from which the B component has been extracted, and also has minute cavities in the portion continuing to the surface.

Because of these missing grooves, the texture and gloss are significantly different from conventional products, but it also has excellent dyeability and antistatic properties.

This is thought to be due to the large surface area due to the missing grooves and cavities, and the structure that allows water absorption.

In addition, component B remains as a core component surrounded by component A, unaffected by solvent extraction, and maintains mechanical properties.
It also has the advantage of being highly adjustable.

Compared to ordinary fibers made using only component A, which accounts for most of the surface layer and middle layer of the composite fiber of the present invention,
The fiber of the present invention exhibits extremely high values such as a dye exhaustion rate of 17 times and an equilibrium moisture content of 25 times.

In order to obtain the fiber of the present invention from the composite fiber precursor, component B is extracted using a solvent. Although it is more efficient to extract component B after it has become a knitted fabric, it is possible to extract it in the form of a yarn before then. You may do so.

The solvent varies depending on the B component polymer, but for example, if B component is styrene, chloroborum, perchlorethylene,
A halogenated hydrocarbon such as trichloroethane is suitable, and a commonly used solvent such as formic acid may be used for nylon 6, and a caustic soda aqueous solution or orthochlorophenol may be used for polyethylene terephthalate.

The extraction conditions may be determined as appropriate depending on the degree of extraction, extraction valve, etc.

The fiber of the present invention will be explained below using an example of a preferred manufacturing method and an actual case.

Example I Polyethylene terephthalate was used as the A component, nylon 6 was used as the B component, nylon 6 was used as the spinning feed component, and the spinning injection temperature was 290°C, 2
A polymer stream was extruded from a twin-screw extruder-type spinning machine set at 80°C in a ratio of A:B=1:1.

The spinneret used had the structure shown in FIG.

That is, a sandbag 1 having two component polymer retention areas 5 and 6 and polymer flow channels 7, 8, 9 and 10 for distributing the polymer in a manner that meets the purpose of the present invention, and a poly flow channel 15. .16 and a mixing agitation zone 17, a spinneret plate 3 having a retention area 18 and a polymer flow path 19 for the polymer flowing out from the polymer flow path 15, a mixing agitation zone 17, and a mixing agitation zone 17. It consists of a spinneret plate 4 having a retention area 20 for polymer flowing out and a polymer outflow nozzle 21.

The flow of the molten polymer will be explained using FIG.

First, A and BZff portions are extruded separately by two extruders, enter a sandbag, are filtered, and enter retention sections 5 and 6, respectively.

The polymer A component that has entered the retention section 5 is guided to the retention sections 11 and 13 through the polymer flow channels 7 and 8, respectively, and the polymer B component that has entered the retention section 6 is guided through the polymer flow channels 9 and 10. through which they are led to reservoirs 12 and 14, respectively.

Polymer A that has entered the retention section 11 flows into the retention section 18 through the channel 15, and forms the same sheath-core composite flow with the polymer B that has flowed out from the retention section 12 through the channel 16, and the polymer flow path Enter 19.

On the other hand, both the polymer A in the retention section 13 and the polymer B in the retention section 14 enter the mixing and agitation zone 17 and are mixed and agitated by a stirring device installed in the agitation section 17 .

The obstruction type stirring device referred to here means screw,
Mixing elements, multi-layered wire mesh, glass bulbs,
Such as wire balls.

The degree of mixing of both components A and B can be adjusted by the length of the mixing and stirring zone and the efficiency of the stirring device.

In this way, the mixture was properly mixed in the mixing stirring area (A+B
) flows into the retention section 20 of the spinneret plate 4.

Next, A flows out from the polymer channel 19.

The (A+B) mixed polymer wraps the concentric sheath-core composite flow consisting of the B2 component, enters the polymer outflow nozzle 21, and is discharged as it is from the spinneret.

The discharged composite polymer stream was run through a conventional spinning cooling cylinder, and while an oil was applied, spinning was performed at a rate of 1000 yn/min.

This undrawn yarn was drawn and twisted at a 10 mm temperature of 70° C., a hot plate temperature of 150° C., and a draw ratio of 325 to obtain a drawn yarn of 75 denier/211 filaments.

The section of this drawn yarn is as shown in FIG. 2 (the dotted lines in the figure represent virtual boundaries), and the skin components are blended in a sea-island pattern.

This drawn yarn was made into a fabric and treated with 65% formic acid at a bath ratio of 1:2.
5. When treated at a temperature of 60°C for 2 hours, the slimy feeling disappeared and a woven fabric with a new texture was obtained.

A schematic diagram of the single yarn after this formic acid treatment is shown in FIG. 3, and the surface has become rough due to the eluting of the nylon 6 component.

When the cross section of the obtained yarn was observed under an optical microscope, it was found that the cross section was as shown in FIG.

In the figure, A is the A component, B (shaded area) is the B component, and C
each represents a cavity created by extracting the B component.

For convenience of explanation, the cross section shown in FIG.
The layers that exist along the line segment Ox, namely the epidermal layer equivalent part I, the intermediate layer part ■, and the innermost layer ■, in which irregular grooves and minute cavities exist, are shown cut away from the part surrounded by It can be seen that there is a region of

The position corresponding to the boundary between the surface layer (and the intermediate layer) is indicated by a dotted line.

As is clear from the cross-section of the fiber in Figure 4, the cross-section of the fiber after formic acid treatment consists of a skin layer (■) with uneven grooves and minute cavities, an intermediate layer (■) consisting of component A, and a layer (■) of component B. It is composed of a sheath-core type internal structure.

Before the B component is extracted, the structure of the structure is the A of the surface layer.
Component 17φ, B component 17%, A component 28% in the middle layer, B component 38% in the innermost layer (expressed as 1.0% by weight of the entire fiber).

The total ratio of A component to B component was 45:55).

The B component extracted from this precursor is 15% of the total, and the extracted composite fiber of the present invention has a 20% A component in the epidermal layer.
The composition was as follows: φ, A component in the middle layer was 33%, and B component in the innermost layer was 45% (assuming the total weight was 100010).

In addition, ordinary polyethylene terephthalate fiber (75d
/24), Pre-1 precursor fiber (before component B extraction 9, the present invention fiber was brought to an absolutely dry state in a vacuum dryer, then left in a constant temperature room at a room temperature of 20 ° C. and a humidity of 65%, and the equilibrium moisture content was determined. The moisture content was found to be 0.4% for regular polyethylene terephthalate fibers, 1.3% for main body fibers, and 1.1% for fibers of the present invention, which are about 2.5 times higher than regular fibers with a flat surface.

The high equilibrium moisture content of the precursor fiber is believed to be due to the presence of nylon 6.

On the other hand, when the dyeing exhaustion rate was also measured according to the usual method, it was found that it was a normal A.
The value was approximately 17 times higher than that of the flat yarn containing only the components.

[Brief explanation of drawings]

FIG. 1 is a partial side sectional view showing an example of a spinneret that is effective for producing the composite fiber of the present invention. This diagram shows a case where a mixing element (also called a static mixer) is used. FIG. 2 shows the fiber of the present invention before component B is extracted, and is a precursor composite fiber. FIG. 3 is an enlarged perspective view of the composite fiber of the present invention. FIG. 4 shows the cross-sectional structure of the fiber of the present invention. In Fig. 4, A indicates the A component, B indicates the B component, and C indicates the cavity from which the B component was extracted. In FIG. 4, ■ indicates the epidermal layer, ■ indicates the middle layer, and ■ indicates the innermost layer. 5...A polymer retention section, 6...B polymer retention section, 7, 8...A polymer flow path, 9
, 10...B polymer flow path, 11.13...
...A polymer retention section, 12.14...B polymer retention section, 15...A polymer flow path, 16
...... B polymer flow path, 17... Mixing stirrer, 18... A polymer retention section, 19...
... A, B combined flow path, 20 ... (A+B) polymer retention section, 21 ... combined outflow nozzle.

Claims (1)

[Scope of Claims] 1. A composite fiber with a three-layer structure using two types of polymers A and B having different solvent solubility, the substantial structure of which is: K) a part or most of component B; (b) A skin layer consisting essentially only of component A, in which complex grooves and microscopic cavities randomly exist in a variety of sizes, generated by the extraction of A solid and homogeneous middle layer consisting only of component A, which exists in a form that envelops the inner layer, and (c) a component that is the same as the above-mentioned extracted component (component B), which exists as a core component in a concentric or eccentric form. A special composite fiber characterized by being composed of three homogeneous innermost layers. Using 22 extruders, a portion of each of the separately extruded polymer streams of the two components A and B, which have different solvent solubility, is introduced into a mixing and stirring zone with obstacles installed inside the spinneret. , mixed flow formed by mixing with ferric acid (A+B)
Ingredients and single A above. Both components B are combined to form a composite fiber precursor consisting of three layers (A+B):A:B in which the (A+B) component occupies the outermost layer, and then from the outermost layer of the composite fiber precursor, one of the components B is combined. A method for producing a special composite fiber having fine irregularities on the surface and minute cavities near the surface, the method comprising extracting part or most of the fiber with a solvent.