JP4248360B2 - Composite web manufacturing method - Google Patents

Description

  The present invention relates to a method for producing a composite web.

As a method for manufacturing a composite web in which an elastic member is laminated between two webs, the following Patent Documents 1, 2, and 3 are known. Such composite webs are used as disposable wearing articles such as diapers, pants, incontinence pads, sanitary napkins and the like. Such a composite web deforms according to the human body shape and thus provides a good fit for the wearer.
WO01 / 88245 (Abstract) JP 2000-514730 A (summary) JP-A-8-58007 (Claim 14)

Patent Document 1 discloses a method of generating a composite web by sandwiching a large number of elastic yarns between two webs.
Patent Document 2 discloses a method of generating a composite web by sandwiching a mesh-like elastic member between two webs.
Patent Document 3 discloses a method of generating a composite web by directly ultrasonically bonding the two webs with a mesh-like elastic scrim sandwiched between the two webs.

However, each of Patent Documents 1 to 3 does not disclose a composite web stretched in the width direction.
Accordingly, an object of the present invention is to provide a method for producing a composite web stretched in the width direction.

  In order to achieve the above object, according to a manufacturing method of the present invention, an elastic body formed of a thermoplastic resin is provided between a plurality of guide tapes spaced apart from each other in the width direction orthogonal to the flow direction, and the elastic body Forming the erected object, expanding the space between the guide tapes to extend the erected object, sandwiching the elongated erected object between the first and second webs, and Generating.

According to the present invention, the elastic body is constructed between the guide tapes. For this reason, the stability of both sides of the erected object is enhanced, and therefore the erected object does not partially extend even when the guide tape portion is pulled in the width direction. Therefore, it is possible to obtain a high-quality composite web stretched in the width direction.
Moreover, since the stretched construction object is sandwiched between two webs, a stretchable composite web can be obtained even if the web itself is not elastic. Even if a construction object is sandwiched between elastic webs, an excellent stretchable composite web can be obtained.

  In the present invention, the guide tape may be cut from the composite web. For example, when the guide tape does not have elasticity, the stretchability of the composite web is improved by cutting the guide tape. When manufacturing a product using a composite web, it may be preferable that the composite web does not deform due to its elasticity. In such a case, it is not a manufacturing process of the composite web but a process of manufacturing a subsequent product. The guide tape may be excised.

In this invention, the said guide tape is an elastic member, and before producing | generating the said composite web, you may include the process of extending | stretching the said construction object in the said flow direction.
By extending the construction object in the flow direction, it is possible to produce a composite web that can expand and contract in two directions.

Embodiments of the present invention will be described below with reference to the drawings.
Fig.1 (a) is an external view of the composite web manufacturing apparatus of a certain Example. At least two guide tapes T and T are put into both ends of the cooling drum 10 at a predetermined interval. The guide tapes T and T move while being wound around the cooling drum 10. On the cooling drum 10, a melt (molten resin) M of a thermoplastic resin (hereinafter referred to as “resin”) is applied in a mesh shape and cooled. As a result, the molten resin M is installed between the two guide tapes T and T, and is solidified to form the installation object P.

  The molten resin M can be applied in a mesh shape by ejecting the molten resin M from a nozzle (gun). The molten resin M may be applied in a planar shape by a coater, spiral, curtain, spray or the like. The erected object P and the guide tape T may be bonded together by a press roll (not shown) sandwiching the erected object P and the tape T. As long as the construction tape P can be formed, the guide tape T may be any member, but may be a thermoplastic elastic resin. In this case, it may be ejected from the nozzle in the same manner as the resin for construction objects.

  Further, a groove may be cut in the cooling drum 10, the molten resin M may be supplied to the groove, and the resin filled in the groove may be connected to the guide tape T and extended in a later process.

  The resin is a kneaded product or a mixture containing a thermoplastic polymer resin as a main component and containing at least one of a tackifier, a viscosity modifier, an antioxidant, a thermal stabilizer, an ultraviolet absorber, a filler, and a plasticizer. It may be. Thermoplastic polymer resins include polyurethane, polyolefin (EVA (ethylene-vinyl acetate copolymer), APAO (amorphous, poly, alpha, olefin)), rubber (SIS (styrene / isoprene / styrene copolymer). ), SEBS (styrene / ethylene / butadiene / styrene copolymer), SEPS (styrene / ethylene / propylene / styrene copolymer)), polyamide-based and polyester-based resins, etc. Used.

  After the cooled and solidified resin (the construction object P) is separated from the cooling drum 10 together with the guide tape T, it is sent to the widening drum 20.

  The widening drum 20 has a plurality of pads 21 capable of rotating. The pad 21 has holding means 22 for holding the tape T on the pad 21. The holding means 22 may be one in which a protrusion such as a needle protrudes and the protrusion hooks the guide tape T. Alternatively, the guide tape T may be held on the pad 21 by pressing the guide tape T against the pad 21 with a nail or the like.

FIG. 2 is a development view of the widening drum 20. As the locus shown in FIG. 2 moves, the distance between the guide tapes T and T is increased in the width direction of the construction object P by the movement of the pad 21. Thereby, the construction object P is expanded in the width direction.
That is, each pad 21 receives the construction object P at the receiving position R1 having the narrow width Wt in FIG. 2 during one rotation of the drum 20, and then holds the guide tape T in FIG. As the pad 21 rotates, the pad 21 moves to both sides of the drum 20 so that the space between the pads 21 and 21 is expanded. The holding means 22 releases the holding of the pad 21 in order to pass the construction object P to the delivery drum 30 at the delivery position R2 after the construction object P has been widened. The transfer drum 30 sucks and receives the guide tape T and the erected object P that are extended in the width direction.

  Thereafter, the widened construction P is sandwiched by the nip rolls 41 and 42 together with the two webs W1 and W2 to form a composite web W3. The two webs W1 and W2 may be bonded to each other using the adhesiveness of the resin, but hot melt may be applied to the web or a construction object as necessary. Moreover, you may increase the adhesiveness of the two webs W1 and W2 by heat embossing the composite web W3.

  In addition, when the guide tape T is unnecessary, the guide tape T may be cut and removed. The case where the guide tape T is unnecessary is a case where the composite web does not require the guide tape T. The case where the guide tape T is necessary is considered to be a case where the stretched guide tape T is used as an elastic member for the waist when the composite web is used for diapers or pants, for example. As a cutting method, a cutter, a laser, or the like is used.

  In the above embodiment, the widening drum 20 is used to extend the construction object P in the width direction. In order to extend the construction object P in the width direction and the flow direction, a re-pitch widening drum 20A shown in FIG. 3 can be used instead of the widening drum 20.

  FIG. 3 is a schematic view of a composite web manufacturing apparatus according to an embodiment. The erected object P can be extended in the width direction and the flow direction by the re-pitch widening drum. In the receiving position R1 where the pad 21 receives the erected object P, the circumferential interval between the pads 21 and 21 is narrow, but when the pad 21 releases the erected object, that is, the pad 21 passes the erected object P and passes the drum 30. Since the interval in the circumferential direction of the pads 21, 21 is widened at the transfer position R <b> 2 that passes to the construction object P, the construction object P can be extended in the flow direction of the construction object P. In addition, the process of widening the construction object P in the width direction is as described above.

The method of extending the construction object P in the width direction and the flow direction is not limited to the method using the re-pitch widening drum.
For example, the construction P released from the widening drum 20 in FIG. 1 may be stretched in the flow direction. For example, the construction object P discharged from the widening drum 20 is moved at a speed higher than the peripheral speed of the widening drum 10 by a roller, a belt, or the like, so that the construction object P can be extended in the flow direction. is there. The subsequent steps are the same as in the above-described example.

  The manufacturing method of this invention can produce | generate the composite web used for disposable wearing articles, such as a disposable diaper, pants, an incontinence pad, and a sanitary napkin.

1 is a schematic perspective view showing a method for producing a composite web according to Example 1. FIG. It is an expanded view of the drum which shows the locus | trajectory of a pad. 6 is a schematic side view showing a method of manufacturing a composite web according to Example 2. FIG.

Explanation of symbols

T: Guide tape P: Construction object W1: First web W2: Second web W3: Composite web

Claims (4)

A step of laying an elastic body formed of a thermoplastic resin between a plurality of spaced apart guide tapes, and forming a structure of the elastic body;
Widening the space between the guide tapes in order to extend the construction object;
And sandwiching the stretched structure between the first and second webs to produce a composite web. A step of laying an elastic body formed of a thermoplastic resin between a plurality of spaced apart guide tapes, and forming a structure of the elastic body;
Widening the space between the guide tapes in order to extend the construction object in the width direction; sandwiching the extension construction object between the first and second webs;
Cutting the guide tape from the composite web to produce a composite web.   The method for manufacturing a composite web according to claim 1, wherein the guide tape is an elastic member, and includes the step of stretching the installation object in the flow direction before generating the composite web.   4. The method of manufacturing a composite web according to claim 1, 2 or 3, comprising a step of adding emboss to the composite web.

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