JP5280471B2 - Method for producing disposable wearing article - Google Patents

Description

  The present invention relates to a method for manufacturing a worn article that is intended to be used only once, taking a disposable diaper as an example, and the manufacturing method includes a step of attaching a thread-like member having elastic extensibility to a sheet material in the worn article. Is included.

  Conventionally, in this type of wearing article, an adhesive may be used when a thread-like member having elastic extensibility such as a rubber thread is attached thereto. The adhesive may be applied to the surface of a sheet material such as a non-woven fabric forming the wearing article with a required width, or may be intermittently applied to the surface of the thread member in the length direction of the thread member.

  In the conventional art, in the wearing article in which the adhesive is applied to the sheet material, it is preferable to make the application width of the adhesive as narrow as possible so that the flexibility of the sheet material is not impaired by the cured adhesive. . However, in general, in a production line for disposable wearing articles in which a sheet material and an extensible thread-like member move at a high speed, it is difficult to accurately position both of them, so there is a limit to narrowing the adhesive application width. There is. This means that the flexibility of the sheet material is impaired over a width much wider than the width of the thread-like member. In a worn article using a plurality of thread-like members arranged in parallel, flexibility is impaired over a wider width.

  Further, when the adhesive is intermittently applied in the length direction of the thread-like member, when the thread-like member moving at high speed vibrates or twists, the applied adhesive becomes a sheet material to which the thread-like member is to be attached. It becomes difficult to securely attach the thread-like member to the sheet material without facing each other.

  In this invention, when attaching a thread-like member having elastic extensibility in the length direction to the sheet material of the disposable wearing article, the touch of the disposable wearing article is not impaired by widely applying the adhesive. In addition, it is an object to improve the method for manufacturing the wearing article so that the thread-like member can be securely attached to the sheet material.

  In order to solve the above-mentioned problem, the present invention is intended for a thread-like shape having elastic extensibility in the length direction with respect to a liquid-permeable top sheet and a liquid-impervious back sheet forming a disposable wearing article. It is the manufacturing method of the said wearing article including the process of attaching a member with an adhesive agent.

In this method, the present invention is characterized as follows.
In the step of attaching the thread-like member, the adhesive is applied to the peripheral surface of the thread-like member in a substantially continuous line, and then the thread-like member is attached to the liquid-permeable surface sheet and the liquid-impermeable back surface. A step of attaching to the sheet is included. In a development view of the peripheral surface obtained by extending the peripheral surface in the y-axis direction on an xy plane including an x-axis extending in the length direction and a y-axis orthogonal to the x-axis, The continuous line draws a curve extending along the x-axis while repeating undulations in the y-axis direction around the x-axis. The height of the undulation is larger than the peripheral length of the thread member. The thread-like member is attached to the liquid-permeable surface sheet by the adhesive at the end of the continuous line in the y-axis direction, while the thread-like is attached by the adhesive at the central portion of the continuous line in the y-axis direction. Attaching the member to the liquid-impermeable back sheet,
The thread members is divided into a plurality of compartments in the x axis direction, Ri Do different length of one period in the compartment adjacent coated area of the adhesive in the surface sheet, of the adhesive of the backsheet The peripheral surface of the thread-like member that is wider than the coating area and that faces the top sheet is third-classed into a central area that includes the long axis of the thread-like member in the y-axis direction and both side areas that do not include the long axis In this case, the application area of the adhesive in the central area is wider than the application area of the adhesive in the both side areas .

The present invention has the following preferred embodiments.
(1) The curve in the developed view repeats undulations with a substantially uniform period and amplitude in at least a part in the x-axis direction.
(2) The folded portion of the end portion in the y-axis direction in the continuous line of the adhesive is a portion that protrudes toward one side and the other side when the thread-like member is attached to the top sheet. And the convex portion toward one side and the convex portion toward the other side are alternately arranged in the x-axis direction, and each of the thread-like members is Intersects the long axis.

  In the method of the present invention including the step of attaching a thread-like member having elastic extensibility in the lengthwise direction to the sheet material in the production line of the disposable wearing article, a substantially continuous line in which the adhesive extends substantially the entire circumference of the thread-like member Therefore, when the sheet material and the thread-like member forming the wearing article are continuously supplied at a high speed, even if the thread-like member rotates or twists, It contacts the sheet material and adheres securely.

The partial fracture perspective view of a disposable diaper. The fragmentary perspective view of a thread-like member and front and back sheets. The expanded view of the surrounding surface of a filamentous member. Drawing similar to FIG. 2 which shows an example of an embodiment. Drawing similar to FIG. 3 which shows an example of an embodiment. Drawing similar to FIG. 2 which shows another example of an embodiment. Drawing similar to FIG. 3 which shows another example of an embodiment.

  The details of the method for producing a disposable wearing article according to the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a partially broken perspective view of a disposable diaper 1 obtained by using the method according to the present invention. The diaper 1 is one of disposable wearing articles targeted by the present invention, a liquid-permeable top sheet 2, a liquid-impervious back sheet 3, and a liquid-absorbent core 4 interposed between the two sheets. Have The front and back sheets 2 and 3 extend from the periphery of the core 4 and overlap each other and are joined together to form front and rear end edge flaps 6 and 7 and a pair of side edge flaps 8 and 9. In the front and rear end edge flaps 6, 7, a plurality of filamentous members extending in the width direction of the diaper 1 and having elastic extensibility in the length direction are used as the waist elastic member 11 for the top sheet 2 and the back sheet 3. It is attached in an extended state. Further, in the side edge flaps 8 and 9, a plurality of thread-like members extending in the front-rear direction of the diaper 1 and having elastic extensibility in the length direction are the leg-hole elastic members 12, and the top sheet 2 and the back sheet 3 is attached in an extended state. A tape fastener 15 is attached in the vicinity of the rear end edge flap 7 in the side edge flaps 8 and 9.

  FIG. 2 is a partial perspective view of a single waist elastic member 11 and a top sheet 2 and a back sheet 3 which are sheet materials to which they are bonded. The elastic member 11 has a substantially circular cross section and has a thread shape. The elastic member 11 has a peripheral length A and a long axis C, and has elastic extensibility in the direction of the long axis C. An adhesive 14 is applied to the peripheral surface 13 of the elastic member 11 so as to advance along the long axis C while drawing a continuous curve 16 as shown in the figure.

The manner in which the curve 16 advances from left to right in FIG. 2 is as follows. The peripheral surface 13 in the figure has a front portion 13a and a back portion 13b, and the first imaginary line 17 drawn on the front portion 13a is parallel to the long axis C and bisects the front portion 13a up and down. It intersects the curve 16 at points P, S, T, W, and X. The second imaginary line 18 drawn on the back surface portion 13b bisects the back surface portion 13b vertically and intersects the curve 16 at points D and E. The curve 16 proceeding to the right from the point P travels around the elastic member 11 in the direction indicated by the arrow 21 about a quarter of the time to reach the point Q, and then proceeds along the back surface portion 13b of the peripheral surface 13 in the direction indicated by the arrow 22. Passing through the point D, the elastic member 11 is turned about 1/2 and reaches the point R. Next, the curve 16 again advances through the front portion 13a in the direction of the arrow 23, and reaches the point S after making a quarter turn of the elastic member 11. Between the point P and the point S, the curve 16 goes around the elastic member 11. Further, the curve 16 advances from the point S in the direction of the arrow 24 and exceeds the imaginary line 17 and then reverses to reach the point T. The curve 16 proceeding from the point T travels in the directions of the arrows 26, 27, and 28, passes through the points U, E, and V, and reaches the point W to make a round of the elastic member 11 again. Subsequently, the curve 16 advances from the point W in the direction of the arrow 29 and reaches the point X. The curve 16 that advances from the point X in the direction of the arrow 31 draws a locus having the same shape as when starting from the point P. Therefore, the period from the point P to X is one cycle of the curve 16. The elastic member 11 in which the adhesive 14 forms such a curve 16 is supplied to and adhered to the required portions on the inner surfaces of the top sheet 2 and the back sheet 3 in an expanded state. At this time, when the elastic member 11 is in line contact with the top sheet 2 at the first imaginary line 17 and is in line contact with the back sheet 3 at the second imaginary line 18, the elastic member 11 has points P and S with respect to the top sheet 2. , T, W, X..., And adhered to the back sheet 3 at points D, E. Even when the elastic member 11 is rotated or twisted around the major axis C in the direction of the arrow 36 or in the opposite direction from the state shown in the drawing when it is supplied to the front and back sheets 2 and 3, the front and back sheet 2 , 3 is in line contact with the peripheral surface 13, the adhesive 14 is always present somewhere in the line contact, and the elastic member 11 with respect to the top sheet 2 and the back sheet 3. Is securely bonded. When the bonded elastic member 11 contracts, the top sheet 2 is gathered between points P and S, S and T, T and W, and W and X, and the back sheet 3 is between points D and E. Gathers.
As shown in FIG. 2, the application area of the adhesive 14 on the top sheet 2 is larger than the application area of the adhesive 14 on the back sheet 3, and the waist elastic member (thread member) 11 on the side facing the top sheet 2. Area of the elastic member 11 in the y-axis direction is divided into three equal parts, the central area 44 including the long axis C and the both side areas 45 not including the long axis C. However, it is wider than the application area of the adhesive in both side regions 45. Further, as shown in FIG. 2, the folded portion of the end portion in the y-axis direction in the continuous line of the adhesive 14 is a portion that protrudes toward one side when the elastic member 11 is attached to the top sheet 2. A portion that protrudes toward the other side, and a portion that protrudes toward the one side and a portion that protrudes toward the other side are alternately arranged in the x-axis direction. It intersects with the major axis C of the elastic member 11.

  FIG. 3 is a view when the peripheral surface 13 of the elastic member 11 shown in FIG. 2 is developed in a planar shape. A curved line 16 is drawn on a plane formed by the peripheral surface 13. In the developed view, the peripheral surface 13 is viewed from the direction of the arrow 37 in FIG. 2, that is, the peripheral surface 13 is viewed from the back portion 13 b side, and the x-axis in FIG. It corresponds to the second virtual line 18 in FIG. The y-axis is orthogonal to the x-axis, and the xy plane including these x-axis and y-axis is the same as the plane formed by the peripheral surface 13 and coincides with the paper surface of FIG. The front portion 13a of the peripheral surface 13 is divided into two vertically by a cut line that coincides with the first imaginary line 17, and the upper half that is curved in the front portion 13a is extended in the direction of the arrow 38 and curved. The lower half is extended in the direction of arrow 39. The value of the y-axis represents the circumferential dimension of the elastic member 11 with the x-axis as the center. Lines 41 and 42 passing through m and −m on the y-axis and parallel to the x-axis are shown in FIG. Matches one virtual line 17. That is, the distance from the x axis to m and −m is equal to ½ of the circumferential length A of the elastic member 11.

  In FIG. 3, points corresponding to the points P to X, D, and E in FIG. 2 are indicated by the same character. Further, in order to understand the entire shape of the curve 16 which is a continuous line, a portion 51 located between the points S and T and a portion located between the points W and X in the curve 16 in the curve 16. 3, the imaginary line part 51 located below the straight line 42 passing through -m and the phantom line part 52 located above the straight line 41 passing through m are shown in FIG. In FIG. 3, the curve 16 drawn on the xy plane draws a sine curve-like curve that repeats ups and downs around the x-axis. Is larger than the perimeter A. Such a curve 16 forms a continuous line extending over the entire circumference of the elastic member 11.

FIG. 4 is a drawing similar to FIG. 2 showing an example of the embodiment of the present invention. In the elastic member 11 of this figure, the curve 16 drawn with the adhesive 14 is not substantially intersecting with the first imaginary line 17 but is in a substantially contacted state. 11 is greater than the perimeter A. Also in this case, the adhesive 14 forms a curved line 16 extending over the entire circumference of the elastic member 11 in a substantial sense. When the elastic member 11 is bonded to a sheet material such as a flexible non-woven fabric or plastic film forming the top sheet 2 or the back sheet 3, the contact between the elastic member 11 and the sheet material is the first virtual line 17 or When the contact can be a wide contact centered on these virtual lines 17, 18 instead of a narrow line contact along the second virtual line 18, the curve 16 does not intersect the first virtual line 17 as shown in the figure. The object of the present invention can be achieved even in a state of almost contact.

  FIG. 5 is also the same drawing as FIG. 3 showing an example of the embodiment of the present invention. The curve 16 drawn on the peripheral surface 13 extended on the xy plane advances along the x-axis while repeating sine-curve undulations at a uniform height 43 as in FIG. Yes. However, the curve 16 in the figure is such that the one cycle D to F in the section I is short, the one period G to I in the section II is long, and the one period J to L in the section III is short again. The period changes in the portion along the line. The curve 16 can change the period at an appropriate portion along the x-axis as in this illustrated example.

  6 and 7 are also similar to FIGS. 2 and 3 showing an example of the embodiment of the invention. As apparent from FIG. 7, the curve 16 drawn by the adhesive 14 on the xy plane is meandering so as to meander an S-shape or an inverted S-shape between values m and -m on the y-axis. Advancing along the axis. In the case of the elastic member 11 having the curve 16, depending on the position in the length direction, for example, at the position a shown in the figure, the virtual lines 71 parallel to the y-axis intersect points b, c, It is possible to adhere to the top sheet 2 or the back sheet 3 with any of d. Further, at the position e, it can be bonded to the top sheet 2 or the back sheet 3 only at a point f where the virtual line 72 intersects the curve 16. As apparent from FIG. 6, since the elastic member 11 can be bonded to the surface sheet 2 at points b and d, it is possible to increase the bonding area with the surface sheet 2 as compared with the example of FIGS. It is. As is clear from the examples of FIGS. 2 and 3 and FIGS. 6 and 7, the curve 16 can have various shapes on the xy plane.

  In the diaper 1 in which the elastic member 11 is used, when the front and back sheets 2 and 3 are different from those in the illustrated example and are elastically extensible, they are elastic with respect to the sheets 2 and 3. The member 11 can also be bonded in an unstretched state. Moreover, the elastic member 11 can also be adhere | attached in the non-expanded state with the non-extensible or extensible front and back sheet | seats 2 and 3 which formed the gather previously. The elastic member 11 can be bonded to other sheet materials forming the diaper 1 in addition to bonding to the front and back sheets 2 and 3. The elastic member 12 around the leg can also be bonded to the diaper 1 in the same manner as the elastic member 11 around the waist. Other elastic members of the diaper 1 can also be bonded by the method of the present invention.

  In the present invention, the curve 16 formed by the adhesive 14 on the peripheral surface 13 of the elastic member 11 is preferably continuous as in the illustrated example. However, even if the curve 16 is intermittent, if the elastic member 11 can be attached to the top sheet 2 or the back sheet 3 in the same manner as that of FIG. It is considered continuous. For example, the curve 16 may be formed by the adhesive 14 applied intermittently as a large number of small dots or short lines. Although there is no special restriction | limiting in selection of the kind of the adhesive agent 14, For example, a hot-melt-adhesive can also be used. In the continuous production line of the diaper 1, when the elastic member is continuously run in one direction and the hot-melt adhesive melted by heating is sprayed onto the elastic member from above in the vertical direction by a spiral spray method, FIG. The elastic member 11 having the adhesive application pattern illustrated in 4 can be obtained. The obtained elastic member 11 is brought into contact with the top sheet 2 and the back sheet 3 before the adhesive 14 is cured. There may be a method of rotating the elastic member 11 around the major axis C to spread the adhesive 14 over the entire peripheral surface 13, but in the method according to the present invention, compared to such a method, Thus, it is not necessary to rotate the elastic member, and the adhesive application process in the diaper production line is simplified.

  A nonwoven fabric or an apertured plastic film can be used for the top sheet 2 of the diaper 1 for carrying out the method according to the present invention, and a plastic film can be used for the back sheet 3. For the core 4, pulverized pulp or a mixture of pulverized pulp and superabsorbent polymer powder can be used. In addition to the diaper 1, examples of disposable wearing articles targeted by the present invention include disposable training pants, sanitary napkins, disposable gowns for medical use, disposable trousers, etc. Any of the elastic members of these wearing articles can be implemented. As the elastic members 11 and 12 according to the present invention, in addition to those having a circular cross section as illustrated, those having a flat oval shape, a polygon such as a rectangle, and other appropriate shapes can be used. In the present invention, there is no particular restriction on the material of the elastic member.

1 Disposable wearing articles (disposable diapers)
11 Threaded member (elastic member)
13 Peripheral surface 14 Adhesive 16 Continuous line 43 Height
44 Central area
45 Both sides A Perimeter C Long axis

Claims (3)

A method for producing a wearing article, comprising a step of attaching a thread-like member having elastic extensibility in a length direction to a liquid-permeable top sheet and a liquid-impervious back sheet forming a disposable wearing article with an adhesive. In
In the step of attaching the thread-like member, the adhesive is applied to the peripheral surface of the thread-like member in a substantially continuous line, and then the thread-like member is attached to the liquid-permeable surface sheet and the liquid-impermeable back surface. A step of attaching to a sheet, and obtained by extending the peripheral surface in the y-axis direction on an xy plane including an x-axis extending in the length direction and a y-axis orthogonal to the x-axis In the developed view of the peripheral surface, the continuous line draws a curve extending along the x-axis while repeating the undulation in the y-axis direction around the x-axis, and the height of the undulation is around the thread-like member Bigger than the length,
The thread-like member is attached to the liquid-permeable surface sheet by the adhesive at the end of the continuous line in the y-axis direction, while the thread-like member is attached by the adhesive at the central portion of the continuous line in the y-axis direction. Attached to the liquid-impermeable back sheet,
The thread members is divided into a plurality of compartments in the x axis direction, Ri Do different length of one period of the curve in the compartment adjacent,
The application area of the adhesive on the top sheet is wider than the application area of the adhesive on the back sheet,
In the case where the peripheral surface of the thread-like member on the side facing the top sheet is divided into three equal parts in the y-axis direction including a central area including the long axis of the thread-like member and both side areas not including the long axis, The method according to claim 1, wherein an application area of the adhesive in a central area is wider than an application area of the adhesive in the both side areas .   The method according to claim 1, wherein the curve in the developed view repeats undulations with a substantially uniform period and amplitude in at least a part in the x-axis direction. The folded portion of the end portion in the y-axis direction in the continuous line of the adhesive has a convex portion toward one side and a convex portion toward the other side when the thread-like member is attached to the top sheet. And a portion that is convex toward one side and a portion that is convex toward the other side are alternately arranged in the x-axis direction, and each of the major axes of the thread-like member The method of claim 2, which intersects with

Images