JP2916288B2 - Opening method of polyester multifilament bundle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for opening a non-twisted polyester-based multifilament fiber bundle by friction charging, and opening the bundle to a monofilament by compressed air. The filament bundle opened by the method of the present invention can be collected into a sheet and processed into a nonwoven fabric by bonding or entanglement.

[0002]

2. Description of the Related Art A method of opening a continuous multifilament fiber bundle, which has been most proposed at present, is a method in which the surface of the multifilament is charged with static electricity of the same polarity and the coulomb repulsive force is used to open the fiber. There is. If these are roughly classified according to the method of applying static electricity to the multifilament, a method of forcibly applying a high voltage directly or indirectly to the multifilament bundle from the outside to apply static electricity,
There is a method of applying friction to the filament bundle with high-speed air or a guide, or applying friction by contact with a collision plate, or applying static electricity by the action of contact and separation.

In the former method, for example, Japanese Patent Publication No. 37-49
No. 93, JP-B-63-16503, JP-B-6
JP-A-3-42016, Japanese Patent Application No. 2-172466, and the like, and the latter method is disclosed in JP-B-37-4993,
Japanese Patent Publication No. 52-8430, Japanese Patent Publication No. 1-161515, Japanese Patent Application No. 2-108175, and the like. Either method is a proposal for opening a polyester multifilament bundle.

[0004]

According to the study of the present inventors, it has been found that the above-mentioned prior art has the following problems. That is, in the method of forcibly applying a high voltage to the multifilament bundle from the outside, a very high voltage is required to effectively charge the filament, which involves danger and requires equipment such as a power supply and a safety device. There is a common problem that is large.

[0005] On the other hand, Japanese Patent Publication No. 15615/1991 and Japanese Patent Publication No. 52-84 / 1982 using a charging method by friction and contact separation.
No. 30 proposes a method of charging a filament bundle by frictional charging with high-speed air or collision with a plate or the like with high-speed air. In these cases, it is possible to charge the filament bundle relatively easily,
A considerably high speed air flow is required to charge sufficiently to open the fiber, and these air flows have a remarkably large effect of disturbing the opened filament flow, so that it is not possible to obtain a stable and good opening. . Furthermore, the cost of supplying high-speed air is not large and economical.

Japanese Patent Publication No. 37-4993 proposes the application of static electricity to a filament bundle by using only charging by friction between a fixed friction element and a filament bundle. In order to charge effectively, the tension applied to the yarn must be considerably high, and during long-time continuous processing, changes in the frictional state due to abrasion of the friction element, or effects such as abrasion on the multifilament bundle are opened. Makes the continuous continuous process very unstable.

The inventors of the present invention disclosed in Japanese Patent Application No. 2-108175 a fiber bundle by passing a multifilament bundle between a metal roll driven and rotated and a nip roll coated with an elastomer which is rotated by friction between the metal roll and the metal roll. We proposed a method to open multifilament bundles by friction contact peeling electrification. It has been found that this method is not always a very efficient method for charging a polyester-based multifilament bundle. This is presumed to be due to the approach of the triboelectric series of the polyester and the elastomer.

The present invention solves the problems of the prior art described above, and continuously and stably charges a polyester-based multifilament fiber bundle by friction contact peeling with a relatively simple facility and opens the monofilament. It is to provide a method.

[0009]

SUMMARY OF THE INVENTION According to the present invention, a non-twisted polyester multifilament bundle is wrapped with 0.024 kg absolute humidity.
Passed as -H ₂ O / kg-dry air twisted metal Nelson roll under the following atmosphere from entering it is frictionally charged by contact separation between the metal roll and then passed through a air gun that injects compressed air This is a method for opening a polyester-based multifilament bundle, wherein the opening is performed to form a monofilament.

The non-twisted polyester multifilament bundle referred to in the present invention is a fiber bundle formed by forming a thread from a polymer in which monomer molecular chains are linked by an ester bond and forming a continuous filament by stretching, heat treatment, or the like. Basically, it refers to a fiber bundle which is not twisted or entangled between filaments and is not twisted by a twisting operation or the like. For example, polyethylene terephthalate, polybutylene terephthalate, polyarylate multifilament bundle, and the like. Further, it is a modified polyester multifilament in which various general modifying components are copolymerized or added.

According to the present invention, a polyester-based multifilament bundle is electrostatically charged by friction and contact peeling, and is opened to a monofilament by Coulomb repulsion. The multifilament bundle is wound several times so that twist is not mixed in a driving metal roll and a separate roll having different charging characteristics in a charging sequence in a Nelson manner, and is driven and taken off without slipping. The multifilament bundle is repeatedly charged and contacted between the metal roll and the separate roll, and is charged to a high voltage. Since charging is performed by such a method, there is almost no change in the state of the charging unit such as frictional charging with a conventional completely fixed friction element, and continuous processing can be stably performed. Of course, it is also possible to perform the charging treatment by using a conventional friction element. In this case, since the tension applied to the filament bundle can be greatly reduced by contacting and peeling between the rolls, problems such as abrasion of the friction element and fluffing of the filament bundle are reduced, and stable continuous charging can be performed. . Winding the multifilament bundle between the driving metal roll and the separate roll in a Nelson shape prevents the tension fluctuation on the supply side of the multifilament bundle from affecting the opening portion and stably supplies the filament bundle to the air gun to reduce the tension. It is also important for stable opening with tension.

The filament bundle that has passed through the Nelson roll is charged to a high voltage, and can be opened to some extent by setting it in a low tension state. It is necessary to pass through an air gun. The charged filament bundle is sucked by an air gun, jetted with an air flow, advances and becomes almost in a tensionless state, and is opened to a monofilament by the repulsive force of static electricity and the scattering action of air.

Since the filament bundle is driven by the Nelson roll and supplied to the air gun, the air gun does not need a strong suction force for forcibly pulling the bundle and driving it forward. It can be sucked and advanced by a weak suction force that does not wrap around the rolls. In other words, the amount of air blown into the air gun is small and it is economical. In addition, the phenomenon that the air flow emitted from the air gun is small and disturbs the filament flow and the collection web that are opened as in the prior art is also eliminated. Is done.

Next, an important point in the present invention is to reduce the absolute humidity of the working atmosphere in which the polyester multifilament bundle is opened. In the present invention, the surrounding atmosphere in which the contact peeling electrification by the Nelson roll and the fiber opening by the air gun are 0.024 kg-H ₂ O / kg-dry air.
Or less, preferably 0.01 kg-H ₂ O / kg-dry air or less. Absolute humidity of the ambient atmosphere is _{0.024kg-H 2 O / kg-} dry
If it is higher than air, the multifilament bundle will not be electrostatically charged due to friction or contact peeling. In addition, even if charged, the charge easily escapes, and it becomes difficult to open the multifilament bundle to a monofilament shape by the repulsion of the charge. This is because water vapor in the atmosphere promotes water adsorbed on the surface of the apparatus or promotes discharge.

[0015] The spread filament obtained by the method of the present invention is deposited on a wire mesh belt conveyor-like collector that moves continuously by the amount of air released from the air gun to form a web, and then calendered. The fibers can be bonded or entangled by a method such as needle punching or binder application to obtain a filament nonwoven fabric.

[0016]

EXAMPLES Next, the embodiments of the present invention will be described with reference to specific examples, but the present invention is not limited to these examples.

[0017] Example 1, under an atmosphere of absolute humidity of approximately _{0.010kg-H 2 O / kg-} dry air by the untwisted multifilament bundle of Comparative Example 1 Polyethylene terephthalate (300dr / 144f) a first view of the apparatus, the yarn When an opening test was performed at a processing speed of 1000 m / min, a good opening state could be obtained stably for a long time at an air flow rate of 0.20 Nm ³ / min. 0.03kg absolute humidity for comparison
When the same treatment was performed under an atmosphere of -H ₂ O / kg-dry air, the filament bundle hardly spread.

Comparative Example 2 The procedure of Example 1 was repeated except that a nip roll made of silicon rubber was provided on the driving metal roll to press the fiber bundle. In this case, although the fiber bundle was opened, the opening width was extremely narrow, and the openability was poor.

Example 2 When a bundle of polyarylate filaments of 500dr / 100f was spread in the same manner as in Example 1, a good spread state was obtained. However, in this case, it was necessary to slightly increase the air flow rate.

Example 3 A bundle of polyethylene terephthalate filaments of 1000dr / 192f was treated with the apparatus shown in FIG.
Under an atmosphere of _{5kg-H 2 O / kg-} dryair, yarn processing speed 1500
When a fiber opening test was performed at an air flow rate of 0.4 Nm ³ / min at m / min, it was possible to stably open the fiber over a long period of time.

Example 4 When a 450-dr / 150f polybutylene terephthalate filament bundle was subjected to a fiber opening test under the same conditions as in Example 1, the fiber could be stably opened for a long time.

[0022]

According to the method of the present invention, various polyester-based multifilament bundles can be efficiently and stably opened to a monofilament shape. The obtained opened filament is propelled onto a wire mesh belt conveyor-like collector that is continuously moved by an air flow emitted from an air gun to form a web, and then calendering, needle punching, a method of applying a binder, and the like. By forming an appropriate entanglement or adhesion between the fibers, a uniform nonwoven fabric can be obtained.

[Brief description of the drawings]

FIG. 1 is an explanatory view schematically showing a filament bundle opening apparatus used for carrying out the present invention.

[Explanation of symbols]

 1 untwisted continuous multifilament supply bobbin 2 untwisted continuous multifilament before opening 3 tensioning device 4a metal roll 4b separate roll 5 air gun 6 compressed air inlet 7 multifilament after opening

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-4-11040 (JP, A) JP-A-57-205542 (JP, A) JP-A-50-126960 (JP, A) JP-A 48-48 73543 (JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) D02J 1/18 D04H 3/00

Claims (1)

(57) [Claims] 1. A non-twisted polyester multifilament bundle is passed through a metal Nelson roll in an atmosphere having an absolute humidity of 0.024 kg-H ₂ O / kg-dry air or less so as not to be twisted. A method of opening a polyester-based multifilament bundle, which comprises triboelectrically charging by contact peeling, and then passing through an air gun which sprays compressed air to open to a monofilament shape.