JP4898050B2 - Method and apparatus for forming a composite fleece by hydraulic needling - Google Patents

Description

[0001]
It is known from EP-A-0333209 that the elastomeric endless fibers together with the wood pulp fibers are bonded together hydraulically, thereby fixing the composite fleece. A problem with the pre-fixing method is that many pulp fibers are washed away from the system, i.e., the fibers are lost. In fact, the outer layer of such a composite fleece is prone to pilling as described in WO 90/04066. In order to improve it is proposed in EP-A-0540041 to treat the endless fiber fleece hydraulically before the pulp fiber feed. This not only gives the fleece high strength, but also attempts to give the fleece acceptability to pulp fibers for improved liquid dispersion properties. After this step, only the pulp fibers (wood fibers) are needling, i.e. needle-stabbed, and then dried or mechanically pressed into the fleece for bonding with the fleece.
[0002]
Not all the above manufacturing methods for fleece products can cope with actual conditions. For example, the tendency of pilling outside composite fleeces, especially endless fiber fleeces, is inevitable.
[0003]
The object of the present invention is to provide a method for the formation of a composite fleece and an apparatus for the method, to improve the surface wear resistance by the method and the apparatus and to improve the pulp fiber in the supporting fleece. To achieve the conclusion. Furthermore, it is to ensure that the applied pulp layer is not lost by effective bonding with the supporting fleece.
[0004]
In order to solve the above-mentioned problems, the present invention starts from the technique described in EP-A-0540041, and the non-woven fabric is preliminarily fixed (preliminary bonding process) before coating with a superabsorbent material. And then a wood pulp layer is applied, both of which are fixed together by a hydraulic water needling and then dried. Fixing the endless fiber fleece by calendering prior to further processing not only improves the wear resistance of the final product, but also reduces pulp loss during fleece water needling. It is considered that calendar processing is not performed strongly. If the immobilization is too strong, there are too many bonding points, making it difficult to bond the pulp layer to the calendered fleece by water needling. For this reason, the fleece may be calendered only once at the end of the bonding process after drying to improve the pilling tendency, thereby obtaining a tight bond of all surface fibers. In the case of a fleece product having only one nonwoven layer, only the roller adjacent to the nonwoven layer need be heated.
[0005]
It is also advantageous to calender the surface of the pulp layer in some cases hot. As a result, so-called hydrogen bonding of the cellulose fibers is performed, and as a result, a paper-like dense surface is obtained on the side of the wood pulp fibers. Such products can also be used for medical purposes, in which case the non-woven may be further hydrophobic for the formation of surgical gowns.
[0006]
The pulp layer is hydraulically (hydrodynamic) bonded to the fleece during manufacture. For further improvement, another endless fiber or card fleece, pre-fixed or pre-fixed on the pulp layer, is applied and these three layers are hydraulically needled together . It is also advantageous to perform a final calendaring. Instead of an endless fiber fleece, it is also advantageous to use a calendered card fleece as a support fleece, which is then subjected to a non-woven fabric (spunbond flies) as a cover layer.
[0007]
A suitable device for carrying out the method is schematically shown in the drawings:
FIG. 1 is a side view of a continuous device for forming a composite fleece comprising only one support base,
FIG. 2 is a side view of the apparatus supplemented with the supply apparatus for supplying the apparatus of FIG. 1 with an additional cover layer of endless fiber fleece in front of the water needling apparatus, and FIG. It is a side view of the apparatus comprised with the card apparatus in the inlet_port | entrance for formation of the card fleece as a support layer with respect to the apparatus of 2. FIG.
[0008]
Endless fibers 2 which are known per se and therefore continuously flow out of the device 1 shown schematically are fed on an endless belt 3 running in the direction of the arrow 4 on the lower side. A calender device 5 is arranged corresponding to the endless belt 3, and the calender device is lightly compressed as necessary to form a fixed fleece with energy and heat as necessary. The anchoring action is so small that the pulp can be more closely bonded with the endless fiber fleece by needling. After such a process, the supply of pulp fibers is carried out in a known manner, for example using the apparatus 6 disclosed in EP-A-0032772. Both fleece layers are then loaded together by a hydrodynamic needling device 7 for bonding, which is carried out on the permeable drum shown in FIG. 2 instead of on the endless belt shown in FIG. It may be done. Next, a drying process using once-through air on the mesh drums 8 and 9 is performed. In the device 8, a blower is directly arranged corresponding to the end face of the mesh drum. Eventually another calendering 15, 16 is performed here, also at a higher energy. This fixing is strongly done to give the final product a sufficiently high wear resistance. In the embodiment shown in FIG. 1, only the roller 16 in contact with the nonwoven fabric should be heated.
[0009]
The continuous device shown in FIG. 2 is similar to the continuous device shown in FIG. 1, where a second endless fiber fleece 12 that is slightly fixed in advance is formed by the device 10, The endless fiber fleece may be fed through a single roller (not shown), i.e. pre-fixed. This is also true for the support fleece formed by the devices 1-4 of FIG. In any case, the upper cover fleece 12 should be preliminarily fixed using the calendar device 11. After the cover fleece 12 has been placed on the pulp layer applied by the device 6 onto the basic fleece by the devices 1, 5, so-called water needling is carried out from both sides in the embodiment, possibly in several places, This is because the pulp layer is covered with fleece on both sides. For this purpose, the needling drums 13 and 14 arranged at the front and rear are used, and the needling drum is meandered and wound, and the upper side is indicated by an arrow corresponding to the needling drum. An implied nozzle beam is arranged. Subsequently, drying is performed here using a different type of ventilation dryer 9, and a blower is arranged outside corresponding to the mesh drum 9 'of the ventilation dryer. Eventually, the calendering devices 15 and 16 may also be passed here, in which case both rollers 15 and 16 may be heated.
[0010]
Up to now, although only the formation of the nonwoven fabric for the subsequent calendering has been described, it is of course possible to form a card fleece as a support layer instead of the nonwoven fabric, and the card fleece is supplied to the calender device 5 and preliminarily fixed. Then, the pulp layer 6 is applied on the fleece. This is illustrated in FIG. For this purpose, card machines 1 'to 4' are used as fleece forming apparatuses. The card machine has a case supply part 1 'and a vibration chute 2' arranged below the supply part, and the vibration chute distributes the fibers evenly over the entire width so that the card machine scraping roller Deliver to 3 '. The subsequent endless belt 4 delivers the received card nonwoven fabric to the calendar device 5 described above. As the cover layer 12, a non-woven fabric is supplied after the pulp layer, and the non-woven fabric may be formed by the unit 10 schematically shown. It is also possible to use a non-woven fabric as the support fleece, and the non-woven fabric is applied to the non-woven fabric after the pulp layer. In this case, the unit 10 constitutes a device represented by reference numerals 1 'to 4', whereas a nonwoven fabric forming apparatus similar to that represented by reference numerals 1 and 2 is arranged instead of the card machine.
[Brief description of the drawings]
FIG. 1 is a side view of a continuous device for forming a composite fleece with one support base.
FIG. 2 is a side view of an apparatus obtained by supplementing the apparatus of FIG. 1 with an additional cover layer supply apparatus;
FIG. 3 is a side view of a device configured to include a card device at an inlet for forming a card fleece as a support layer with respect to the device of FIG. 2;
[Explanation of symbols]
1 device, 2 endless fiber, 3 endless belt, 5 calender device, 6 device, 7 needling device, 8,9 mesh drum, 10 device, 12 endless fiber fleece, 13,14 needling drum

Claims (2)

  A method for forming a two-part composite fleece for the manufacture of sanitary products comprising at least one support fleece formed by a nonwoven and a wood pulp layer applied on the support fleece, wherein the nonwoven is highly absorbent Calendered for pre-fixation before coating with a wood pulp layer made of the following materials, then applied with a wood pulp layer, both by hydraulic water needling together as a two-part composite fleece Before fixing, apply a cover layer to the wood pulp layer of the two-part composite fleece, provide a calendered card nonwoven fabric as the cover layer, and all of the support fleece, wood pulp layer and card nonwoven fabric are hydraulic water A hydraulic fleece with a composite fleece, characterized by fixing by needling and then drying The method for forming the ring. An apparatus for manufacturing a hygiene product comprising by implementing the method of claim 1 Symbol placement with a wood pulp layer made of high-absorbency material nonwoven fabric,
a) Non-woven fabric device (1, 2; 10; 1 'to 4'),
b) Calendar device (5, 11),
e) a directly connected device (6) for applying a wood pulp layer to a calendered support fleece;
f) Water needling device (7; 13, 14) for directing the water jet to the wood pulp layer;
g) a drying device (8, 9);
h) consists of another calendar device (15, 16),
For the formation of the cover layer before the hydraulic water needling device (1, 2, 5),
c) The card nonwoven device (10) is connected, and following the card nonwoven device,
d) Device for forming a composite fleece by hydraulic needling, characterized in that a calender device (11) for pre-fixation and then a water needling device (13, 14) are connected.

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