JP3873894B2 - Method for manufacturing elastic elastic member - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a stretchable elastic member. More specifically, the present invention relates to a manufacturing method for obtaining a stretchable elastic member that is neatly arranged and has a good appearance without causing irregularities of elastic bodies at a cutting portion.
[0002]
[Prior art]
Conventionally, it is well known that a stretchable elastic member used for an absorbent article such as a paper diaper is formed by applying an adhesive between two layers of sheet members and arranging and fixing the elastic body in an elongated state. In addition, the adhesive is intermittently applied between the two-layer sheet members, the elastic body is arranged and fixed in an expanded state, and then the sheet is cut at the non-applied portion of the adhesive, and intermittently applied to the obtained sheet. It is also well known to form a stretchable elastic member provided with a stretchable portion. In addition, as a disposable diaper having a discontinuous elastic member, a laminated body in which an elastic member is arranged between upper and lower sheets is passed between a first roll in which a plurality of convex portions are arranged and a second roll facing the same. A paper diaper has been proposed in which a stretchable sheet formed by cutting a stretchable member by pressurization and heating is attached to a stretchability imparting portion (see, for example, Patent Document 1).
In addition, as a method for obtaining a discontinuous elastic member, an elastic body is stuck on a base sheet so as to have an adhesive part and a non-adhesive part, and then only the elastic body of the non-adhesive part is subjected to pressure cutting. A method for manufacturing an elastic member has been proposed (see, for example, Patent Document 2).
[0003]
[Patent Document 1]
JP 2002-35029 A (FIGS. 1 and 9)
[Patent Document 2]
Japanese Patent Laid-Open No. 2000-26015 (FIG. 1)
[0004]
[Problems to be solved by the invention]
In order to form a non-stretchable portion, a conventional elastic member has a stretched elastic body disposed between a sheet provided with a fixed portion and a non-fixed portion, and the elastic body is cut together with the sheet at the non-fixed portion. Since the overlapping sheets are not bonded and fixed in the non-fixed portion, the absorbent member is formed from the non-bonded sheet portion when such a stretchable elastic member is disposed on a part of the diaper to be used. Absorbent polymer may leak out.
In addition, when alternately forming a plurality of stretchable parts and non-stretchable parts, the elastic body is arranged between the sheet provided with the fixed part and the non-fixed part, and the non-fixed part is obtained by cutting the elastic body, In such a method, when the cut elastic body is contracted by its own contracting force, it moves freely in the non-fixed part, so that the plurality of elastic bodies bend or bend and become irregular and unpleasant in appearance. It becomes.
Moreover, in the paper diaper as described in Patent Document 1, since the elastic member is cut at a plurality of locations, a large number of cut elastic member materials remain in the cutting region, which is very unpleasant. The stretchable elastic member obtained by the method described in Document 2 has a plurality of elastic properties because when the elastic body is cut at the non-bonded portion, the elastic body that is cut is moved freely at the non-bonded portion when the cut elastic body contracts. The body bends or breaks, making it uneven and unsightly.
[0005]
The present invention improves the problems of the conventional method for producing a stretchable elastic member, and even when applied to a diaper, the absorbent polymer or the like does not leak out from the cut portion of the sheet. It is an object of the present invention to provide a manufacturing method capable of obtaining a good-looking elastic elastic member having a cleanly arranged cut portion without causing irregularities of the formed elastic body.
[0006]
[Means for Solving the Problems]
This invention for improving the problem which the manufacturing method of the said conventional elastic elastic member has includes the following each invention.
[0007]
(1) A method for producing a stretchable elastic member in which stretchable regions and non-stretchable regions are alternately formed by fixing a thread-like or belt-like elastic body between two sheets in an expanded state and then cutting the elastic body. Because
After applying an adhesive to at least one of the two-layer sheets so as to form a strong adhesion portion and a weak adhesion portion, and then placing and fixing the elastic body in an extended state, the elastic body is attached to the weak adhesion portion. A method for producing a stretchable elastic member to be cut.
[0008]
(2) The adhesive is intermittently applied to one of the two-layer sheets, and the adhesive is applied continuously or intermittently to the other, and the elastic body is disposed between the two sheets and bonded together. In this case, the strong adhesive portion and the weak adhesive portion are formed by forming a region where the adhesives of both sheets overlap and a region where the adhesive of only one sheet exists. The manufacturing method of the elastic elastic member of description.
[0009]
(3) The method for producing a stretchable elastic member according to (1) or (2), wherein the elastic body is cut at one place in each weakly bonded region.
[0010]
(4) The two-layer sheet is passed through a cutting roll composed of a smooth roll facing a roll having a convex portion, and the elastic body is cut by pressurization and / or heating (1) The method for producing a stretchable elastic member according to any one of items (1) to (3).
[0011]
(5) The method for producing a stretchable elastic member according to (4), wherein only the roll having the convex portion is heated.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
In the stretchable elastic member of the present invention, an adhesive is applied to at least one of the two-layer sheets so as to form a strong adhesion portion and a weak adhesion portion, and then the elastic body is arranged and fixed in an extended state, and then the weak adhesion portion. In this method, the elastic body is cut. The stretchable elastic member manufactured by such a manufacturing method has stretch regions and non-stretch regions alternately formed, and even when the sheet is cut, the cut portion is bonded, so when applied to a used diaper In addition, the absorbent polymer or the like does not leak from the cut portion of the sheet, and the cut elastic body does not become uneven, and the cut portion is neatly arranged and has a good appearance. In this case, a non-adhesive region may be provided in the region where the elastic body is disposed, and the elastic body may be disposed linearly or may be disposed in a curved shape.
[0013]
In the present invention, a method of forming a strong adhesive portion and a weak adhesive portion on a two-layer sheet is a method of changing the amount of adhesive applied to one sheet and alternately applying two types of adhesives having different adhesive strengths. It can form by the method of arrange | positioning. In addition, when an adhesive is intermittently applied to one of the two-layer sheets, an adhesive is applied continuously or intermittently to the other sheet, and an elastic body is placed between the two sheets and bonded together In addition, by forming a region where the adhesives of both sheets overlap and a region where the adhesive of only one sheet is present, a strong adhesive portion and a weakly adhesive portion can be formed. The method of forming a strong adhesion portion by the area where the adhesives of both sheets overlap is easy to implement on equipment and can be fixed more firmly by fixing the elastic body from both sides, so the amount of adhesive is small This is preferable because the flexibility of the stretchable part is improved because it is low in cost and low in adhesive.
[0014]
In the present invention, the method of cutting the elastic body is such that the sheet on which the elastic body is disposed passes between cutting rolls composed of a combination of an upper blade and a lower blade, or passes through a rotating blade that operates, etc. Is obtained by cutting the sheet together. In addition, when forming a non-stretchable part without cutting the sheet, the sheet is passed between a cutting roll made of a smooth roll facing a roll having a convex part, and pressure is applied between the convex part and the flat surface of the smooth roll. Thus, it can be formed by cutting the elastic body in the weakly bonded region. Furthermore, although it can cut more easily by heating, it is preferable to heat only the convex roll side and not actively heat the smooth roll side. Heating a smooth roll that is always touched by the sheet is not preferable because it may cause the sheet to harden by heat. The heating temperature is preferably 80 to 250 ° C.
[0015]
Further, the shape of the cutting convex part for cutting the elastic body provided on the convex part roll may be any shape, and may be one that cuts one elastic body at one place or one that cuts at a plurality of places. Alternatively, a plurality of elastic bodies may be cut at a time, but in particular, a shape in which one elastic body is cut at one place in one weak adhesion region is preferable. When the elastic body is cut at a plurality of locations, the cut pieces of the elastic body remain in the sheet and the appearance is deteriorated. More preferably, in the plurality of cutting projections provided on the axis of the projection roll, each cutting projection preferably cuts one elastic body. Moreover, it is preferable that the shape of the cutting convex portion is a shape that is arranged obliquely with respect to the flow direction of the sheet. By making such a shape, the cut surface is difficult to open when the sheet is cut. Become. Further, the cutting by the cutting convex portion may cut only the elastic body or may be cut together with the sheet.
[0016]
In the present invention, the weakly bonded portion is weaker than the strongly bonded portion that fixes the elastic body, so that the elastic body is not firmly fixed to the sheet. Although it contracts by force, the contraction direction linearly contracts along the locus on which the elastic body is adhered, so that the elastic body does not break or bend and looks good. Moreover, 5-80% of the adhesive force of a strong adhesion part is preferable for the adhesive force of a weak adhesion part. If the adhesive strength exceeds 80%, the elastic body is fixed and the non-stretchable portion cannot be formed. On the other hand, if the adhesive strength is less than 5%, stable adhesion cannot be achieved. More preferably, it is 50% or less. Fixing the weakly bonded portion does not need to be strong, and it is sufficient that the sheets are weakly bonded. Therefore, it is preferable to use a low adhesive force because the cost is low.
[0017]
Sheets used in the present invention are polyester, polypropylene, polyester, synthetic fibers made from other thermoplastic resins, etc., non-woven fabrics made of natural fibers such as rayon and cotton, woven fabrics, films such as polyethylene and polypropylene, tissue Any sheet can be used as long as it is in the form of a sheet such as a pulp sheet, and a composite sheet in which two or more layers of different materials are stacked may be used.
Further, the two layers of sheets sandwiching the elastic body may be the same material or different materials. Further, the elastic body may be sandwiched by folding one sheet.
[0018]
As the elastic body used in the present invention, those having a shape such as a urethane film, urethane yarn, urethane foam, natural rubber or the like, a strip shape, or a net shape in which yarns are arranged vertically and horizontally are used. In the case of a thread, 300 to 4000 denier is preferable. In the case of a strip shape, the thickness is preferably 0.01 to 0.4 mm.
[0019]
By the method for producing a stretchable elastic member of the present invention, a stretchable elastic member in which stretchable regions and non-stretchable regions are alternately formed is obtained. Further, even when the sheet is cut, a stretchable elastic member to which the sheet of the non-stretchable part is bonded is obtained.
When the elastic member of the present invention is used as a stretchable elastic member around a leg or abdomen of disposable absorbent products such as disposable diapers, or a stretchable elastic member of a leak-proof gather, the absorbent member or the like is placed between unbonded sheets. The elastic elastic member can be arranged at a free position without leaking. In particular, when an elastic body is disposed in a portion where the absorber is located, it can be formed as a non-stretchable portion by the method of the present invention.
[0020]
【Example】
Hereinafter, the method for producing the elastic elastic member of the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.
FIG. 1 is a schematic view showing a method for producing a stretchable elastic member of the present invention, and FIGS. 2 and 3 are schematic views showing a section of a cut portion of the stretchable elastic member of the present invention.
[0021]
In FIG. 1, an upper layer sheet 1 continuously fed from a feeding device is intermittently coated with an upper layer adhesive 5 by an adhesive coating device 12, and a lower layer sheet continuously fed from another feeding device. 2, the lower layer adhesive 7 is continuously applied by the adhesive application device 13, and the plurality of elastic bodies 3 continuously drawn out from the elastic body feeding device are separated by a predetermined distance by the elastic body guide roll 14. Are arranged between the upper layer sheet 1 and the lower layer sheet 2 and fed to a press roll 15 comprising a pair of rolls. In this case, the guide roll 14 can be replaced with a metal bar or the like.
Next, the upper layer sheet 1, the lower layer sheet 2, and the elastic body 3 disposed between the two sheets pass between a pair of press rolls 15 and are pressed and bonded to form the laminated sheet 4. In this case, a region where the upper layer adhesive 5 of the upper layer sheet 1 and the lower layer adhesive 7 of the lower layer sheet 2 are overlapped is formed with a strong bonding portion 8 that expresses a strong adhesive force for bonding the elastic body 3 from both sides, The region where the adhesive-uncoated portion 6 of the upper layer sheet 1 and the lower layer adhesive 7 of the lower layer sheet 2 overlap each other has a weak adhesive force because the elastic body 3 is bonded only on one side of the lower layer adhesive 7, thereby forming a weakly bonded portion 9. Thus, the laminated sheet 4 having the strong adhesion portions 8 and the weak adhesion portions 9 alternately is formed.
[0022]
The laminated sheet 4 formed by disposing the elastic body 3 in the strong adhesion portion 8 and the weak adhesion portion 9 then passes between the cutting rolls 18 formed of the smooth rolls 17 facing the convex portion rolls 16.
As shown in FIG. 2 and FIG. 3, the convex roll 16 and the smooth roll 17 are not in contact except when the convex part 19 of the convex roll 16 hits the smooth roll 17, and the laminated sheet 4 contacts the smooth roll 17. In contact. As the sheet 4 moves, the convex roll 16 and the smooth roll 17 also rotate, and in the weakly bonded part 9, the convex part 19 of the convex roll 16 and the smooth roll 17 are contacted and pressurized, and the elastic body 3 is cut. .
In this case, as shown in FIG. 1, cutting convex portions 20 are formed on the convex portions 19 of the convex portion roll 16 in accordance with the number of the elastic bodies 3. One cutting projection 20 is applied. In this case, it is preferable that the cutting convex portion 20 is disposed obliquely with respect to the flow direction X of the laminated sheet 4 and the convex portion roll 16 is heated.
[0023]
Thus, a continuous body of stretchable elastic members in which the weakly bonded portions 9 having the non-stretchable portions 10 and the strong bonded portions 8 having the stretchable portions 11 are alternately formed from the laminated sheet 4 that has passed between the cutting rolls 18 is formed. Is done. In the non-stretchable part 10, the cut elastic body 3 cannot be fixed by the adhesive force of the weak adhesive part 9, and thus contracts and loses stretchability. Therefore, the elastic body 3 contracts along the arranged locus and is neatly arranged without being bent or bent.
[0024]
A continuous body of stretchable elastic members formed by the method of the present invention in which stretchable portions and non-stretchable portions are alternately formed is cut at appropriate intervals, and the legs, abdomen, and leak-proof gathers of disposable absorbent articles such as paper diapers. It can be used as a material for elastic members such as. In the present invention, it is possible to freely arrange a plurality of stretchable parts and non-stretchable parts.
[0025]
【The invention's effect】
The stretchable elastic member obtained by the production method of the present invention can be favorably used as a material for an elastic member such as a leg circumference, an abdomen circumference, and a leakage prevention gather of a disposable absorbent article such as a disposable diaper.
In addition, according to the present invention, it is possible to freely arrange a plurality of stretchable parts and non-stretchable parts. Particularly, when forming a stretchable part that crosses the absorbent body, a portion where the absorbent body is placed is formed. By making it non-stretchable, it is effective in preventing a decrease in absorption performance.
Furthermore, since the sheet | seat of a non-expandable part is adhere | attached, the absorbent article which an absorber does not leak out can be formed.
[Brief description of the drawings]
FIG. 1 is a schematic view showing a method for producing a stretchable elastic member of the present invention.
FIG. 2 is a schematic view showing a cross section of a cut portion of the elastic elastic member of the present invention.
FIG. 3 is a schematic view showing a cross section of the cut portion of the stretchable elastic member of the present invention continued from FIG. 2;
[Explanation of symbols]
1. Upper sheet 2. Lower sheet 3. Elastic body 4. Laminated sheet 5. 5. Upper layer adhesive 6. Adhesive uncoated part Lower layer adhesive 8. 8. Strong adhesion part Weakly bonded part 10. Non-stretchable part 11. Elastic part 12. Adhesive application device 13. Adhesive application device 14. Elastic body guide roll 15. Press roll 16. Convex roll 17. Smooth roll 18. Cutting roll 19. Convex part 20. Cutting convex part X. Laminate sheet flow direction

Claims (5)

A method for producing a stretchable elastic member in which a stretchable region and a non-stretchable region are alternately formed by fixing a thread-like or belt-like elastic body between two sheets in an expanded state and then cutting the elastic body. ,
After applying an adhesive to at least one of the two-layer sheets so as to form a strong adhesion portion and a weak adhesion portion, and then placing and fixing the elastic body in an extended state, the elastic body is attached to the weak adhesion portion. A method for producing a stretchable elastic member to be cut. When the adhesive is applied intermittently to one of the two-layer sheets, and the adhesive is applied continuously or intermittently to the other, and the elastic body is disposed between the two sheets and pasted together, The stretchable elasticity according to claim 1, wherein the strong adhesive portion and the weakly adhesive portion are formed by forming a region where the adhesive of both sheets overlaps and a region where the adhesive of only one sheet exists. Manufacturing method of member. The method for producing a stretchable elastic member according to claim 1, wherein the elastic body is cut at one place in each weakly bonded region. The said 2 layer sheet | seat is passed between the cutting rolls which consist of a smooth roll facing the roll which has a convex part, The said elastic body is cut | disconnected by pressurization and / or a heating. The manufacturing method of the elastic elastic member in any one of. The method for producing a stretchable elastic member according to claim 4, wherein only the roll having the convex portion is heated.

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