JPS6025543B2 - Method for manufacturing continuous filament nonwoven fabric with good entanglement properties - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a continuous filament entangled nonwoven fabric which is made flexible and has high strength by properly entangling a fiber aggregate obtained by accumulating continuous filaments by needle punching. be.

Conventionally, fiber aggregates obtained by accumulating continuous filaments have been widely used as general-purpose nonwoven fabrics.

Among these, the use of continuous filament fiber aggregates for the production of leather-like sheet materials has been practiced for a relatively long time. For example, Tsubaki Kosho No. 37-11293, Aya Kosho No. 15
Examples of this can be seen in No. 349, Mochiko Sho 44-29543, and Hakama Ko Sho 48-Madaraban. The techniques disclosed in these documents fix the fibers by directly impregnating the fiber aggregate with a resin that becomes a binder;
Alternatively, it may simply be needle-punched under the same conditions as conventional fiber aggregates made from staples to create apparent entanglement. However, when performing needle punching on a continuous filament aggregate to entangle the fibers, the needle jump resistance is large and the needles often break. The area of the fiber aggregate depends on the number of needle punches that cause fiber cutting,
In particular, there is a momme point where the width becomes large and sufficient entanglement does not occur, and especially when an entangled nonwoven fabric of a continuous filament aggregate is used as a constituent material of a leather-like sheet material, the above-mentioned disadvantages The resulting performance problems as a leather-like sheet material include the so-called ``firm and flexible'' texture, the elimination of blood lines caused by fibers, the unevenness of the surface when pulled in a directional manner, and the tendency to bend. This can be said to eliminate the unevenness of the surface. The object of the present invention is to produce a well-entangled nonwoven fabric by entangling continuous filament aggregates, and in particular a highly tenacious nonwoven fabric with good fiber entanglement that can be used as a constituent material of leather-like sheet materials. The purpose of the present invention is to provide a flexible continuous filament intertwined nonwoven fabric with firmness.

That is, prior to entangling the continuous filament aggregate by needle punching, a specific lubricant is applied, and then needle punching is performed at a needle insertion density of 100 punches/c or more, thereby reducing fiber breakage.
It was also found that the fiber assembly exhibits good fiber integration while being accompanied by area shrinkage. In the method of the present invention, melt-grade filaments are continuously accumulated in a bottle aggregate using a direct jet stream, or melt-spun filaments are drawn between rolls having different speeds and then continuously accumulated in a collector using a jet stream or the like. A method in which a continuous filament aggregate is made, the aggregate is laminated into multiple layers as necessary, and a specific lubricant is applied by spraying, or the aggregate is impregnated by being held between suitable clamping bodies, and the liquid is squeezed out. Alternatively, the oil is applied by a method such as applying with a pair of oil supply rollers, and then dried if necessary, and the humidity is adjusted or simply the humidity is adjusted, or needle punching is performed with an ordinary needle machine while applying the oil. In order to sufficiently entangle the fibers, the needle insertion density needs to be 100 punches/or more.

If the number of punches/punch is less than 100, even if total weaving is performed, there will not be sufficient area shrinkage, and a stiff sewn nonwoven fabric will not be obtained. Therefore, it is desirable to determine the needle punch density based on the areal shrinkage rate of the fiber aggregate, but the conditions are: depth of needle insertion, condition of the needle lock, fiber thickness, thickness of the aggregate, bulk It is determined based on the I property and the desired density based on the use of the entangled nonwoven fabric, but the needle insertion density is 100 punches/
or more, preferably 140 to 3500 punches/me. By adopting such needle conditions, the area of the continuous filament assembly shrinks in accordance with the number of needle punches. The area shrinkage rate is at least 10%, preferably 15 to 40%. This area shrinkage due to needle punching is particularly important for the performance of entangled nonwoven fabrics made of continuous filaments, especially in terms of flexibility, firm texture, bending resistance, stiffness when folded, and uneven elongation when pulled. This is particularly important as it has a large effect on elongation properties.

Therefore, if the areal shrinkage rate is less than 10%, there will be little effect on performance, and if it is more than 40%, needle breakage will increase rapidly and fibers will be cut more frequently, which is not preferable. The needle-punched entangled nonwoven fabric obtained according to the present invention has less fiber breakage, sufficient overall intertwining, has a firm and flexible texture, and has fewer so-called needle marks, which are needle holes, and is smooth. It is an entangled nonwoven fabric with good properties and high strength, and is particularly suitable as a constituent material for leather-like sheet materials.

The specific lubricant used in the present invention has a melting temperature of 40 to 1
20℃ so-called paraffin wax, microcrystalline wax,
It is a paraffin lubricant mainly composed of solid paraffin such as slack wax, and it is preferable to apply this paraffin lubricant in an amount of 3 to 15% by weight based on the weight of the fiber aggregate.

If the amount of this lubricant is small, the effect will be small, and if a large amount is attached, it is also undesirable because of peeling off of the lubricant and resistance to needle insertion. Further, conventionally used emulsions of mineral oil and other oil agents may also be mixed in at a concentration of 3% by weight or less based on the weight of paraffin. This makes it possible to impart hygroscopic properties and antistatic properties to the oil agent.
The lubricant is used in the form of an aqueous dispersion or a liquid dissolved or dispersed in a solvent or dispersant that is a non-solvent for the fibers.
Furthermore, if the melting temperature of paraffin is less than 4,000 degrees Celsius, the paraffin will become sticky, causing many needle breakages, and will not produce good entanglement, while if it is more than 120 degrees Celsius, it will not have sufficient lubricant effect and shrinkage effect during needling. Undesirable. In the needle punching of continuous filament aggregates to which a lubricant has been applied in the present invention, since the lubricant causes the fibers to shrink, the difference between the feed amount in the needle machine and the drawing speed by the delivery roll is equal to the vertical shrinkage of the punching due to the difference of 1 board'. It is necessary to overfeed according to the capacity.

The fibers to which the method of the present invention is applied are usually single-component filaments obtained by spinning or multi-component filaments composed of two or more types of polymeric substances. Embodiments of the present invention will be described below with reference to Examples.

However, the invention is not limited to these examples. Note that parts and percentages refer to weight. Example 1 Nylon-6 with a relative viscosity of 2.95 and polyethylene 50 with a melt index of 70 were made into a melt-grade yarn using an extruder, and a supply roller with a circumferential speed of 30 skin/min installed under the cooling cylinder was used. The spun filament is drawn 2.5 times between a drawing roller with a circumferential speed of 750 minutes, introduced into the inlet of a filament air injection device, passed through a rocker that swings at a speed of 20 times/minute, and is passed onto a wire mesh conveyor. The filaments were collected in a tub to obtain a continuous filament assembly having a weight of about 255 m/m.

This continuous filament aggregate was made by lightly needle punching with a #36 needle to temporarily fix the fibers, then laminating two sheet-like aggregates, then applying oil treatment under the following conditions, and needle punching. The condition of the needle and the performance after needle bunching were compared and summarized in Table 1. 1 Application of oil agent: A solution of solid paraffin dissolved in cyclohexane was applied by a spray method. 2
Needle punch: Needle count #40, regular needle used, penetration depth 14 skin, needle penetration density shown in the table.

In Table 1, the amount of oil adhered is expressed as the oil agent purity relative to the dry fiber weight.

In addition, the quality of the overall nonwoven fabrics was compared by tearing length, relative tensile strength, and sensory tests. However, 100 crack length = tensile strength of sample (k9/arc) x weight (t/re)
10○ Relative tear strength = tear strength of sample (k9) x weight (ta') The sensory test was based on the texture obtained by three people's hands.

Table 1 Comparative Example 17 uses stable This is clear from the results shown in this table.

In other words, in Comparative Examples 1 to 4, there was no oil agent, and as the number of needle punches increased, the area expanded, and the fracture length reached a maximum at a needle punch density of 42 cape/ground, and gradually decreased as the number of needle punches increased. Moreover, the specific tear strength also tends to decrease, and it is clear that the nonwoven fabric fibers are cut and the resulting performance deterioration is significant. In Comparative Examples 5 to 8, the paraffin used in the method of the present invention was used, so the fibers had shrinkage ability, but the needle conditions were the conventional method, and the overfeed amount was 0 to eliminate longitudinal shrinkage. The tearing length did not increase much as the number of needle punches increased, and when the entangled nonwoven fabric was folded using the horizontal line as the fold line, angularity was observed, and the texture was thin, paper-like. is large.

Comparative Examples 9 to 12 are cases where the melting temperature of paraffin is high, and the state of the nonwoven fabric tends to be similar to Comparative Examples 1 to 4 above.

In the case of Examples 13 to 16 of the present invention, needle punching was performed by overfeeding the necessary amount to sufficiently thin the fiber shrinkage, and the tearing length increased as the number of needle punches increased, and the specific tear strength tends to decrease slightly, but the extent is small.

Furthermore, all of these characteristic values are larger than the characteristics of the stitched nonwoven fabric made from staple fibers shown in Comparative Example 17, and the ruts are much stronger. In spite of this, the texture according to the sensory test showed that the texture was firm and flexible, and had a thick texture, indicating that entanglement was sufficiently performed. In Comparative Example 17, the fibers of this example were made into staples according to a conventional method and used as a random weave.

Example 2 Table 2 shows the performance of the overall nonwoven fabric when various oils were applied to the continuous filament assembly sheet obtained in Example 1 and the sheet was needle punched at a needle punch count of 560 P/m.

Table 2 That is, by adding a specific paraffin as shown in Invention Examples 24 to 28, excellent entanglement properties were exhibited by needle punching, and thereby the performance of the entangled nonwoven fabric was also good.

Example 3 Polyethylene terephthalate with an intrinsic viscosity of 0.70 (viscosity measured using a mixture of equal amounts of tetrachloroethane and phenol) was melt-spun, and a peripheral speed of 175 m/min was supplied under the cooling cylinder. A continuous filament assembly having a weight of about 200 denier was prepared using the same method as in Example 1, using the filaments having a straightness of about 3 deniers, which were fed to a roller and drawn by a subsequent drawing roller.

Two sheets of this aggregate are laminated, 4% paraffin wax solution with a melting point of 63 oo is applied by a spray method, and the aggregate is fed to a needle machine, and the aggregate is needle-punched on the supply lattice in a state where there is no tension. A nonwoven fabric was obtained.

Table 3 shows the performance when the number of needle punches is 560P/and the needle penetration depth is 12 legs. As a comparative example, the above paper yarn filament was made into a staple with a fiber length of about 3 denier and 51 ribs according to a conventional method, and after being made into a weave, it was needle punched under the same conditions to obtain an entangled nonwoven fabric. Its performance is also listed in Table 3. did.

Table 3 In other words, it is clear that the product of the present invention has excellent performance.

Claims (1)

[Claims] 1. When manufacturing a continuous filament nonwoven fabric by entangling fibers of a fiber aggregate obtained by accumulating continuous filaments using a needle punch method, the fiber aggregate is mainly composed of solid paraffin with a melting temperature of 40 to 120°C. After applying 3 to 15% by weight of paraffin-based lubricant based on the weight of the fibers, needle punching with a needle insertion density of 100 punches/cm^2 or more is performed to entangle the fibers, and the area of the fiber aggregate is reduced by needle punching. A method for producing a continuous filament nonwoven fabric with good entanglement properties, characterized by shrinkage of at least 10%.