JP7353739B2 - Stretch sheet manufacturing method, stretch sheet manufacturing device, and stretch sheet - Google Patents

Description

The present invention relates to a method for manufacturing a stretchable sheet, an apparatus for manufacturing a stretchable sheet, and a stretchable sheet.

As a method for manufacturing stretchable sheets, a method is known in which a stretched rubber thread is attached between sheets using an adhesive. On the other hand, in Patent Document 1, a stretched rubber thread (wire-like element) is arranged between sheets, and the sheet is pressed by passing it between a pair of rollers, and the thread rubber is A method of forming connections on both sides of the is disclosed. In the narrow portion formed between the connecting portions on both sides of the rubber thread, the rubber thread can be fixed in a state where the tension is removed and the rubber thread has become thicker, and the rubber thread can be attached to the sheet. In this way, by attaching the rubber thread to the sheet without using an adhesive, it is possible to suppress a decrease in the shrinkage performance of the rubber thread and a decrease in flexibility of the stretchable sheet due to curing of the adhesive.

Patent No. 3212615

In the stretchable sheet manufactured as described above, the rubber thread may be cut. In that case, if the distance between the connecting parts (pair of joint parts) formed on both sides of the rubber thread is wide and exceeds the diameter of the rubber thread in the stretched state, or if the stretching ratio of the rubber thread is high, the rubber thread may be cut. In this case, the rubber thread easily slips between the pair of joints, and there is a possibility that the cut ends of the rubber thread cannot be fixed at the desired pair of joints. In this case, it becomes impossible to develop stretchability in the desired region of the stretchable sheet.

The present invention has been made in view of the above-mentioned problems, and includes a stretchable sheet in which a thread rubber is attached to a sheet portion at a pair of joints located on both sides of the thread rubber. The purpose is to fix the cut end of the

The main invention for achieving the above purpose is:
A method for manufacturing a stretchable sheet having longitudinal and transverse directions, the method comprising:
arranging the rubber thread stretched in the lateral direction between the first sheet portion and the second sheet portion;
Pressing the first sheet part and the second sheet part to form a plurality of joint parts joining each other;
cutting the rubber thread,
The plurality of joint portions have a plurality of joint portion pairs located on both sides of the thread rubber in the longitudinal direction and spaced apart in the horizontal direction,
After the cutting step, the contracted rubber thread is sandwiched between the pair of joint parts, and the lateral position of the rubber thread is regulated;
The plurality of pairs of joints include a first pair of joints located on one side in the lateral direction relative to the cutting position of the rubber thread, and a pair of joints located on one side in the lateral direction of the first pair of joints. having a first pair of joints and a second pair of adjacent joints,
In the cutting step, a regulating portion for regulating shrinkage movement of the rubber thread is provided in at least a part of the range from the cutting position to the other end of the second joint pair in the lateral direction. A method for producing a stretchable sheet in which the rubber thread is cut in a state in which the rubber thread is cut,
In the step of forming the joint, forming the joint using an anvil roller and a horn roller that are arranged opposite to each other,
In the cutting step, the rubber thread is cut using a cutter roller and a receiving roller that are arranged opposite to each other on the downstream side of the anvil roller and the horn roller in the conveying direction,
The regulating portion is a pair of nip rollers that rotate while sandwiching a laminate in which the rubber thread is arranged between the first sheet portion and the second sheet portion,
The method for manufacturing a stretchable sheet is characterized in that each of the pair of nip rollers is a roller different from the receiving roller .
Other features of the present invention will become apparent from the description of this specification and the accompanying drawings.

According to such a method of manufacturing a stretchable sheet, in the stretchable sheet where the rubber thread is attached to the sheet part using a pair of joints located on both sides of the rubber thread, the cut ends of the rubber thread are fixed at a desired pair of joints. become more susceptible to

It is a top view of elastic sheet 10 manufactured by the manufacturing method of this embodiment. 2 is a schematic cross-sectional view of the stretchable sheet 10 of FIG. 1. FIG. FIG. 1 is a schematic cross-sectional view of a stretchable sheet manufacturing apparatus 20 in the first embodiment. 2 is a schematic cross-sectional view of an ultrasonic welding device 22. FIG. FIG. 5A is an explanatory view of the surfaces of the anvil roller 23 and the horn roller 24, and FIG. 5B is a schematic enlarged view of the closest portion of the anvil roller 23 and the horn roller 24. 6A and 6B are explanatory diagrams of a method of attaching the rubber thread 14 using the joint j. 7A to 7C are explanatory diagrams of the cutting process of the rubber thread 14. FIGS. 8A to 8C are diagrams illustrating the contraction process of the rubber thread 14 conveyed downstream in the conveyance direction. 9A is a diagram showing an example of the arrangement of the rubber thread regulating section 30, and FIG. 9B is a diagram showing how the rubber thread regulating section 30 regulates the contraction movement of the rubber thread 14. FIGS. 10A to 10C are diagrams showing modifications of the arrangement of the thread rubber regulating section 30. FIGS. 11A and 11B are diagrams showing modifications of the arrangement of the thread rubber regulating section 30. It is a schematic sectional view of the thread rubber regulation part 30 in a 2nd embodiment. It is a top view of the stretchable sheet 10 of 3rd Embodiment. It is a schematic sectional view of the manufacturing device of elastic sheet 10 in a 3rd embodiment.

From the description of this specification and the attached drawings, at least the following matters will become clear.
A method for manufacturing a stretchable sheet having longitudinal and transverse directions, the method comprising: arranging a rubber thread stretched in the transverse direction between a first sheet part and a second sheet part; and the first sheet part. and a step of forming a plurality of joints which are bonded to each other by crimping the second sheet portions, and a step of cutting the thread rubber, wherein the plurality of joints are formed in the thread rubber in the longitudinal direction. has a plurality of pairs of joints located on both sides of the rubber thread at intervals in the lateral direction, and after the cutting step, the contracted rubber thread is sandwiched between the pairs of joints, and the rubber thread is sandwiched between the pairs of joints. The position in the lateral direction is regulated, and the plurality of joint pairs include a first joint pair located on one side in the horizontal direction from the cutting position of the rubber thread, and a first joint pair located on one side in the horizontal direction from the cutting position of the rubber thread The first pair of joints and the second pair of joints are adjacent to each other on one side in the lateral direction, and in the cutting step, the second pair of joints are separated from the cutting position in the lateral direction. A method for producing a stretchable sheet, characterized in that the rubber thread is cut with a regulating portion for regulating contraction and movement of the rubber thread provided in at least a part of the range up to the other end of the rubber thread. be.

According to such a method of manufacturing a stretchable sheet, it is possible to prevent the entire rubber thread from contracting vigorously after cutting the rubber thread, thereby preventing the rubber thread from slipping through the first joint pair. Therefore, the cut ends of the rubber thread are easily fixed at the first joint pair, and elasticity can be developed in a desired region of the elastic sheet.

The method for manufacturing such a stretchable sheet is characterized in that, in the lateral direction, the restriction portion is provided in a range including at least a part of the portion where the first joint pair is located. This is a method for manufacturing a plastic sheet.

According to such a method of manufacturing a stretchable sheet, when the rubber thread is cut, the shrinkage movement of the rubber thread located between the first pair of joints is regulated, so that the rubber thread from the first pair of joints is regulated. It can prevent the rubber thread from slipping through. Therefore, the rubber thread is easily fixed at the first joint pair.

In this method of manufacturing a stretchable sheet, the regulating portion is provided in a range closer to the cutting position than the center between the cutting position and the other end of the first joint pair in the lateral direction. This is a method for manufacturing a stretchable sheet, characterized in that the stretchable sheet is not provided.

According to such a method of manufacturing a stretchable sheet, the cut end portion of the rubber thread can be made thicker by contracting the rubber thread closer to the cutting position than the regulating portion. Therefore, the rubber thread can be prevented from slipping through the first pair of joints, and the rubber thread can be easily fixed in the first pair of joints.

Such a method for manufacturing a stretchable sheet, wherein in the lateral direction, at least a portion of the range from one end of the first pair of joints to the other end of the second pair of joints, This is a method for manufacturing a stretchable sheet, characterized in that the restriction portion is provided.

According to such a method of manufacturing a stretchable sheet, it is possible to prevent the rubber thread from slipping through the first pair of joints, and the cut ends of the rubber thread can be easily fixed at the first pair of joints. Further, since the regulating portion is provided in the region where the rubber thread remains elastic, the rubber thread in the region where the elasticity remains is difficult to contract, and the elongation magnification of the rubber thread is easily maintained.

In the method for manufacturing such a stretchable sheet, in the lateral direction, the first The method for manufacturing a stretchable sheet is characterized in that the regulating portion is provided in an area including at least a part of the portion opposite to the joint portion.

According to such a method of manufacturing a stretchable sheet, since the regulating portion is provided at a position close to the first pair of joints, the cut end of the rubber thread can be easily fixed at the first pair of joints, and , it becomes easier to maintain the elongation ratio of the rubber thread.

In this method of manufacturing a stretchable sheet, the regulating portion is provided in at least a part of the range from the cutting position to the other end of the first joint pair in the lateral direction. A method for manufacturing a stretchable sheet, characterized by:

According to such a method of manufacturing a stretchable sheet, it is possible to prevent the rubber thread from slipping through the first pair of joints, and the cut ends of the rubber thread can be easily fixed at the first pair of joints.

In this method of manufacturing a stretchable sheet, the laminate in which the rubber thread is arranged between the first sheet part and the second sheet part is conveyed to one side in the lateral direction, while the rubber thread is placed between the first sheet part and the second sheet part. is cut, and the regulating part includes a first regulating part provided in a part of the range from the cutting position to the other end of the first joint pair in the lateral direction; a second restriction portion provided in a part of the range from one end of the first pair of joints to the other end of the second pair of joints; The elastic sheet manufacturing method is characterized in that the first part releases the restriction on contraction and movement of the rubber thread before the second restriction part releases the restriction.

According to such a method of manufacturing a stretchable sheet, the thread is stretched by the second regulating part between the time when the cut end of the thread rubber leaves the first regulating part and the time when it reaches the first joint pair. Since the contraction of the rubber is regulated, the elongation ratio of the rubber thread can be easily maintained.

In this method of manufacturing a stretchable sheet, the regulating section is a nip means that rotates while sandwiching a laminate in which the thread rubber is arranged between the first sheet section and the second sheet section. A method for manufacturing a stretchable sheet, characterized by:

According to such a method of manufacturing a stretchable sheet, since the first and second sheet parts and the rubber thread are sandwiched between the nip means in the thickness direction, contraction and movement of the rubber thread can be restricted.

A method for manufacturing such a stretchable sheet, comprising: winding a cutter blade and a laminate in which the thread rubber is arranged facing the cutter roller and between the first sheet part and the second sheet part. The elastic sheet manufacturing method is characterized in that the thread rubber is cut using a conveying receiving roller, and the regulating portion is the receiving roller.

According to such a method of manufacturing a stretchable sheet, since the rubber thread wraps around the outer circumferential surface (for example, a curved surface) of the receiving roller and comes into close contact with it, the shrinkage movement of the rubber thread can be regulated.

This method of manufacturing a stretchable sheet is characterized in that the regulating section is a sealing section in which at least the first sheet section and the second sheet section are crimped together. .

According to such a method of manufacturing a stretchable sheet, the first sheet portion and the second sheet portion are brought into close contact with each other at the seal portion, and the rubber thread located therebetween is sandwiched between the first sheet portion and the second sheet portion. Therefore, contraction and movement of the rubber thread can be restricted.

This method of manufacturing a stretchable sheet is characterized in that the distance between the pair of joints in the longitudinal direction is equal to or larger than the diameter of the rubber thread in the stretched state.

According to such a method of manufacturing a stretchable sheet, even if the rubber thread easily slips between the pair of joints, it is possible to suppress the rubber thread from slipping through the first pair of joints.

Further, the apparatus for manufacturing a stretchable sheet having a longitudinal direction and a transverse direction includes an arrangement part for disposing a rubber thread stretched in the transverse direction between a first sheet part and a second sheet part; The first sheet part and the second sheet part are crimped to form a plurality of joint parts that are joined to each other, and a cutting part cuts the thread rubber, and the plurality of joint parts are: A plurality of pairs of joints are provided on both sides of the rubber thread in the longitudinal direction and spaced apart from each other in the horizontal direction, and after the cutting step, the contracted rubber thread is sandwiched between the pairs of joints. The position of the rubber thread in the lateral direction is regulated, and the plurality of joint pairs include a first pair of joints located on one side in the lateral direction from a cutting position of the rubber thread; a second joint pair adjacent to the first joint pair on one side of the first joint pair in the lateral direction, and in the cutting step, from the cutting position in the lateral direction; The rubber thread is cut in a state where a regulating portion for regulating contraction and movement of the rubber thread is provided in at least a part of the range up to the other end of the second joint pair. This is a stretch sheet manufacturing device.

According to such an apparatus for manufacturing a stretchable sheet, it is possible to prevent the entire rubber thread from contracting vigorously after cutting the rubber thread, thereby preventing the rubber thread from slipping through the first joint pair. Therefore, the cut ends of the rubber thread are easily fixed at the first joint pair, and elasticity can be developed in a desired region of the elastic sheet.

Further, the elastic sheet has a longitudinal direction and a lateral direction, and a rubber thread extending in the lateral direction is arranged between a first sheet part and a second sheet part, the stretchable sheet having a longitudinal direction and a lateral direction. The second sheet parts are joined to each other by a plurality of joint parts, and the plurality of joint parts include a plurality of joint part pairs located on both sides of the thread rubber in the longitudinal direction, spaced apart in the horizontal direction. The rubber thread is cut at a predetermined position in the lateral direction, and is sandwiched between the pair of joints to restrict its position in the lateral direction, and the plurality of pairs of joints are a first joint pair located on one side in the lateral direction from the predetermined position and to which an end of the rubber thread is fixed; and a first joint pair on one side in the lateral direction from the first pair of joint parts. the first pair of joints and a second pair of joints adjacent to each other, at least a portion of the range from the predetermined position to the other end of the second pair of joints in the lateral direction; A high-density region is provided in which the density of the first sheet portion and the second sheet portion is higher than the density of the first sheet portion and the second sheet portion outside the range. It is a stretchable sheet.

According to such a stretchable sheet, after the rubber thread is cut, the entire rubber thread can be suppressed from contracting vigorously and slipping through the first joint pair. Therefore, the cut ends of the rubber thread are fixed at the first joint pair, and elasticity can be exerted in a desired region of the elastic sheet.

===Embodiment===
<<Structure of elastic sheet 10>>
FIG. 1 is a plan view of a stretchable sheet 10 manufactured by the manufacturing method (manufacturing apparatus) of this embodiment. FIG. 1 is a diagram showing the stretchable sheet 10 in a stretched state without wrinkles. FIG. 2 is a schematic cross-sectional view of the stretchable sheet 10 of FIG. 1.

The stretchable sheet 10 has a horizontal direction (stretching direction), a thickness direction, and a longitudinal direction (width direction) that are orthogonal to each other. The stretchable sheet 10 also has a first sheet part 11 and a second sheet part 12 that are stacked in the thickness direction, and a plurality of sheets interposed between the first sheet part 11 and the second sheet part 12. It has a rubber thread 14 and a plurality of joints j.

The plurality of rubber threads 14 are arranged along the horizontal direction of the stretchable sheet 10 and spaced apart from each other in the vertical direction. The rubber thread 14 is attached to the first sheet portion 11 and the second sheet portion 12 in a stretched state. Therefore, the elastic sheet 10 is given elasticity in the direction along which the rubber thread 14 runs. As the thread rubber 14 (thread-like elastic member), in addition to thread-like natural rubber, various known synthetic rubbers such as styrene rubber, urethane rubber, ester rubber, polyurethane, and polyethylene can be used.

The plurality of joint parts j are for joining the first sheet part 11 and the second sheet part 12 to each other by pressure bonding, and are arranged intermittently in the horizontal and vertical directions of the elastic sheet 10. . Further, the plurality of joints j regulate the lateral position of the rubber thread 14 with respect to the first sheet part 11 and the second sheet part 12. As will be described in detail later, the position of the rubber thread 14 in the lateral direction is regulated by a pair of joints jP formed in pairs on both sides of the rubber thread 14 in the longitudinal direction. Although the planar shape of the joint j illustrated in FIG. 1 is a rectangular shape, the planar shape of the joint j is not particularly limited and can be any shape such as an ellipse, a circle, a parallelogram, or the like.

Note that the stretchable sheet 10 in FIG. 2 is composed of two sheets, and for example, one sheet may be folded back, the folded part will be called the first sheet part, and the part that is not folded will be called the second sheet part. It may also be a department. Alternatively, the stretchable sheet 10 may be one in which one or more other sheet parts are stacked on the first and second sheet parts 11 and 12. That is, the stretchable sheet 10 may have three or more layers.

<<Example of use of elastic sheet 10>>
The elastic sheet 10 manufactured by the manufacturing method (manufacturing apparatus) of this embodiment is used, for example, as a component of an absorbent article such as a disposable diaper. In that case, a soft sheet member can be exemplified as the first sheet portion 11 and the second sheet portion 12 that constitute the stretchable sheet 10. For example, it is a nonwoven fabric such as a spunbond nonwoven fabric or an SMS (spunbond/meltblown/spunbond) nonwoven fabric. Further, at least one of the first sheet portion 11 and the second sheet portion 12 may be a stretchable sheet (stretchable film or stretchable nonwoven fabric) that can be stretched in the stretching direction of the stretchable sheet 10. Further, a stretchable film or a stretchable nonwoven fabric may be sandwiched between the first sheet portion 11 and the second sheet portion 12.

Specifically, the stretchable sheet 10 can be used for the ventral waist region and the back waist region of a pants-type disposable diaper. Furthermore, the stretchable sheet 10 can be used in the leg gathers provided on both sides of the absorbent body in the left-right direction of the disposable diaper. In addition, in a tape-type disposable diaper (not shown), the elastic sheet 10 can be used as a side panel for attaching a fastening tape (hook member) to the back waistline.

Furthermore, the elastic sheet 10 can be used not only for pants-type or tape-type disposable diapers, but also as a component of absorbent articles such as pad-type disposable diapers, sanitary napkins, and sanitary shorts-type napkins. be. Moreover, it can be used not only for absorbent articles but also for masks, cleaning sheets, etc.

===Stretchable sheet manufacturing device and manufacturing method===
<<First embodiment>>
(Configuration of stretchable sheet manufacturing apparatus 20)
FIG. 3 is a schematic cross-sectional view of the stretchable sheet manufacturing apparatus 20 in the first embodiment. FIG. 4 is a schematic cross-sectional view of the ultrasonic welding device 22. FIG. 5A is an explanatory diagram of the surfaces of the anvil roller 23 and the horn roller 24. FIG. 5B is a schematic enlarged view of the closest portion of the anvil roller 23 and horn roller 24. 6A and 6B are explanatory diagrams of a method of attaching the rubber thread 14 using the joint j.

The stretchable sheet manufacturing apparatus 20 includes a transport roller group 21 (FIG. 4), an ultrasonic welding device 22, a discharge roller 25, a cutter roller 26, a receiving roller 27, and a thread rubber regulating section 30. The stretchable sheet 10 is manufactured as a continuous sheet that is continuous in the lateral direction. In the stretchable sheet manufacturing apparatus 20, the direction in which materials are continuous is defined as the conveyance direction, and the direction perpendicular to the conveyance direction (that is, the longitudinal direction of the stretchable sheet 10) is defined as the CD direction.

As shown in FIG. 4, the conveyance roller group 21 is arranged upstream of the ultrasonic welding device 22 in the conveyance direction, and conveys the material constituting the elastic sheet 10 and supplies it to the ultrasonic welding device 22. Specifically, the conveying roller group 21 includes a first conveying roller 211 that conveys the continuous body of the first sheet portion 11, a second conveying roller 212 that conveys the continuous body of the second sheet portion 12, and a rubber thread 14. and a third conveyance roller 213 that conveys a plurality of continuous bodies.

The first to third conveyance rollers 211 to 213 are rotated around a rotation axis along the CD direction by a drive source (for example, a motor) not shown. The first to third transport rollers 211 to 213 may be a pair of rollers or a single roller. Alternatively, the material may be supplied to the ultrasonic welding device 22 using a belt conveyor or the like.

Hereinafter, the continuous body of the first sheet part 11, the continuous body of the second sheet part 12, the continuous body of the thread rubber 14, and the continuous body of the elastic sheet 10 will be simply referred to as the first sheet part 11, the second sheet part 12, Also referred to as thread rubber 14 or elastic sheet 10.

The ultrasonic welding device 22 (joint forming section) is for forming the joint j of the elastic sheet 10, and has an anvil roller 23 and a horn roller 24 arranged to face each other. The anvil roller 23 and the horn roller 24 are rotated around a rotation axis along the CD direction by a drive source (not shown).

The outer peripheral surface of the anvil roller 23 is an uneven surface on which a plurality of convex portions 231 are formed, as shown in FIG. 5A. This convex portion 231, together with the horn roller 24, ultrasonically welds the materials to form a joint j. Therefore, the protrusions 231 are arranged in accordance with the arrangement pattern of the joints j in the stretchable sheet 10.

The outer circumferential surface of the horn roller 24 is a smooth surface with no irregularities, and vibrates in a direction that increases or decreases the distance between the horn roller 24 and the surface of the anvil roller 23 (that is, in the thickness direction of the material passing therebetween). The frequency of the vibration is, for example, a predetermined value of 20 kHz to 40 kHz, and the amplitude is, for example, a predetermined value of 20 microns to 60 microns. Therefore, the surface of the horn roller 24 vibrates ultrasonically. Such vibrations are generated by inputting an electric signal of the above frequency to a piezo element of a converter (not shown) connected to the horn roller 24.

Further, in the manufacturing apparatus 20 illustrated in FIG. 4 , the first and second sheet portions 11 and 12 and the rubber thread 14 are wound around the anvil roller 23 and then passed between the anvil roller 23 and the horn roller 24 . The circumferential speed values of the first and second conveying rollers 211 and 212 that convey the first and second sheet portions 11 and 12 are approximately the same as the circumferential speed value of the anvil roller 23, respectively. Therefore, the first and second sheet portions 11 and 12 are wound around the anvil roller 23 in a state in which they are not stretched and are kept taut to the extent that they do not loosen.

On the other hand, the circumferential speed value of the third conveying roller 213 that conveys the rubber thread 14 is approximately 1/the elongation magnification of the circumferential speed value of the anvil roller 23 . The elongation magnification is a magnification R (R=E1/E0) that indicates how many times the total length E1 of the rubber thread 14 in the stretchable sheet 10 in the stretched state is extended to the total length E0 in the unloaded state, which is the natural length. . Therefore, while the thread rubber 14 passes between the third conveyance roller 213 and the anvil roller 23, it is elongated to the above-mentioned elongation magnification and wound around the anvil roller 23 in the elongated state.

The discharge roller 25 is a roller that discharges the semi-finished elastic sheet with the joint j formed therein to the process of cutting the rubber thread 14. The discharge roller 25 is rotated around a rotation axis along the CD direction by a drive source (not shown).

The cutter roller 26 and the receiving roller 27 (cutting section) are rollers that are arranged to face each other on the downstream side of the ultrasonic welding device 22 in the conveyance direction. The cutter roller 26 and the receiving roller 27 are rotated around a rotation axis along the CD direction by a drive source (not shown).

A cutter blade 261 that protrudes outward in the radial direction of the cutter roller 26 is provided on the outer peripheral surface of the cutter roller 26 . In FIG. 3, two cutter blades 261 are provided at an interval in the rotational direction of the cutter roller 26, but the number of cutter blades is not limited to this. The spacing between the cutter blades 261 in the rotational direction corresponds to the spacing between the cutting positions of the rubber thread 14. Alternatively, a plurality of rubber threads 14 arranged in the CD direction (vertical direction) in the elastic sheet 10 may be cut with a cutter blade 261 extending in the CD direction, or a cutter blade 261 provided for each rubber thread 14 arranged in the CD direction may be used. The cutting may be performed using a plurality of cutter blades 261.

A receiving blade 271 that receives the cutter blade 261 of the cutter roller 26 is provided on the outer peripheral surface of the receiving roller 27 . However, the receiving roller 27 does not need to have the receiving blade 271; for example, it may be a roller with a smooth outer peripheral surface, or may be a roller provided with a groove portion for receiving the cutter blade 261. .

The rubber thread regulating section 30 is for regulating the contraction movement of the rubber thread 14 when the cutter roller 26 and the receiving roller 27 cut the rubber thread 14 . In the first embodiment, a nip roller (a pair of rollers 31 and 32) that pinches the thread rubber 14 is used as the thread rubber regulating section 30.

(Manufacturing method: process of forming joint part j)
In the method for manufacturing the stretchable sheet 10 using the manufacturing apparatus 20 having the above configuration, first, as shown in FIG. It is supplied to the roller 23. Specifically, in the radial direction of the anvil roller 23, the rubber thread 14 is supplied so as to be located outside the first sheet portion 11, and the rubber thread 14 is located inside the second sheet portion 12. Ru. In this way, the rubber thread 14 is placed between the first sheet part 11 and the second sheet part 12 in a stretched state in the conveyance direction (lateral direction).

Next, the first and second sheet parts 11 and 12 and the rubber thread 14 wound around the anvil roller 23 are conveyed to the ultrasonic welding device 22 by the rotation of the anvil roller 23, and are transported between the anvil roller 23 and the horn roller 24. pass through. At this time, the ultrasonic welding device 22 ultrasonically welds (presses) the first sheet part 11 and the second sheet part 12 to form a plurality of joint parts j that are joined to each other.

Specifically, the first and second sheet parts 11 and 12 are melted and joined together by receiving ultrasonic vibration from the horn roller 24 at a position corresponding to the convex part 231 of the anvil roller 23. At this time, the thread rubber 14 is located in the groove 232 (see FIGS. 5A and 5B) of the anvil roller 23 and is not ultrasonically welded. In addition, in FIG. 4 etc., the thread rubber 14 is located on the convex part 231 of the anvil roller 23 for the sake of clarity of the drawing. However, the rubber thread 14 is actually located in the groove 232.

Further, as described above, the plurality of joints j serve to regulate the lateral position of the rubber thread 14 with respect to the first sheet part 11 and the second sheet part 12, that is, the role of regulating the position of the rubber thread 14 in the lateral direction with respect to the first sheet part 11 and the second sheet part 12. It also plays the role of attaching the thread rubber 14 to the parts 11 and 12. To this end, in this embodiment, as shown in FIG. Form.

Further, as shown in FIG. 6A, in the CD direction (longitudinal direction), the distance Dj between the pair of joints jP located on both sides of the rubber thread 14 is the distance Dj in the CD direction of the rubber thread 14 stretched when forming the joint j. The diameter shall be D14 or more. Furthermore, it is assumed that the interval Dj is smaller than the diameter of the rubber thread 14 in the CD direction in its natural length in an unloaded state. The rubber thread 14 in the stretched state is thinner than the thickness of the rubber thread 14 in its natural state by the amount of stretching. Therefore, after the continuous body of the rubber thread 14 is cut after the formation of the joint j, the elongated state of the rubber thread 14 is relaxed, and as shown in FIG. 6B, it tends to expand in the CD direction while contracting in the transport direction. The rubber thread 14 is sandwiched between the joint pair jP. As a result, the lateral position of the rubber thread 14 is regulated, and the rubber thread 14 is attached to the sheet portion.

However, the present invention is not limited to the above, and the distance Dj between the pair of joints jP may be smaller than the diameter D14 in the CD direction of the rubber thread 14 that is stretched when forming the joint j. That is, the joint j may be formed while the rubber thread 14 is compressed by the space surrounded by the groove 232 of the anvil roller 23 and the horn roller 24. Further, a part of the rubber thread 14 may be pressed together with the first and second sheet parts 11 and 12 by the convex part 231 of the anvil roller 23 and the horn roller 24. Also in this case, the rubber thread 14 is sandwiched between the pair of joints jP in the stretchable sheet 10, the lateral position of the rubber thread 14 is regulated, and the rubber thread 14 is attached to the sheet portion.

Moreover, the joint part forming part that forms the joint part j is not limited to the ultrasonic welding device 22, but may be any device that can press and join a plurality of sheet parts to each other. For example, the joint j (thermal welding part) may be formed using a heat sealing device. The heat sealing device is a pair of heated rollers, one of which has a convex portion on its outer peripheral surface that corresponds to the joint j, and the other roller that has a convex portion on its outer peripheral surface that corresponds to the joint j. An example is a roller that receives

Further, although FIG. 4 shows an example of the ultrasonic welding device 22 that includes a pair of rollers, the present invention is not limited thereto. Instead of the horn roller 24, a non-rotating horn having a flat vibrating surface placed opposite the surface of the anvil roller 23 may be used. Further, the horn side that vibrates ultrasonically may be a roller-shaped device, and the anvil side may be a device that does not rotate and has a flat surface that receives ultrasonic vibrations. Further, the vibrating surface on the horn side may be an uneven surface, and the surface on the anvil side may be a smooth surface. Moreover, both the horn side and anvil side surfaces may be made into uneven surfaces.

(Manufacturing method: Process of cutting the rubber thread 14)
7A to 7C are diagrams showing the rubber thread 14 and the joint pair jP in the stretchable sheet 10, and are explanatory diagrams of the process of cutting the rubber thread 14. 8A to 8C are diagrams illustrating the contraction process of the rubber thread 14 being conveyed downstream in the conveyance direction. FIG. 9A is a diagram showing an example of the arrangement of the rubber thread regulating section 30, and FIG. 9B is a diagram showing how the rubber thread regulating section 30 regulates the contraction movement of the rubber thread 14.

The method for manufacturing the stretchable sheet 10 of this embodiment includes the step of cutting the rubber thread 14 after forming the joint j. Therefore, as shown in FIG. 3, the laminate 10' of the first and second sheet parts 11, 12 and the rubber thread 14, on which the joint j is formed, is conveyed by the discharge roller 25, and is transported to the cutter roller 26 and the receiver. It passes between rollers 27. At this time, the cutter blade 261 is inserted into the laminate 10' supported by the receiving blade 271, and the rubber thread 14 is cut.

In addition, in the step of cutting the rubber thread 14, the first sheet portion 11 and the second sheet portion 12 may be cut and separated together with the rubber thread 14, or only the rubber thread 14 may be cut and separated, and the second sheet portion 12 may be cut and separated. The first sheet portion 11 and the second sheet portion 12 may not be separated.

For example, when cutting a continuous body of stretchable sheet 10 into parts size of an absorbent article, it is preferable to cut and separate the first sheet part 11 and the second sheet part 12 together with the thread rubber 14. On the other hand, the stretchability may be partially removed from the stretchable sheet 10. For example, when the elastic sheet 10 is used for the ventral and dorsal girths of a pants-type disposable diaper, in order to ensure the flatness of the absorbent body, it is necessary to Elasticity may be removed from areas that overlap with the absorbent body. In this case, it is preferable to cut and separate the elastic sheet 10 at the center of the rubber thread 14 extending in the lateral direction so that the first sheet part 11 and the second sheet part 12 are not separated. However, if the first sheet part 11 and the second sheet part 12 are separated together with the thread rubber 14, no cut marks will be left on the stretchable sheet 10, so the appearance of the stretchable sheet 10 can be improved.

Further, in the stretchable sheet 10, stretchability is developed from the position where the cut end portion 14a of the thread rubber 14 cut in the stretched state is fixed by the joint portion pair jP. For example, as shown in FIG. 7A, a pair of joints located on one side in the lateral direction of the cutting position Pc of the rubber thread 14 in the lateral direction is defined as a first pair of joints jP1, and Also, a pair of joints adjacent to the first pair of joints jP1 on one side in the lateral direction is defined as a second pair of joints jP2. As shown in FIG. 7B, when the cut end 14a of the rubber thread 14 is fixed by the first joint pair jP1, the stretchability is lower on one side in the lateral direction than the first joint pair jP1. manifest.

Therefore, the pair of joints jP to which the cut ends 14a of the rubber thread 14 are to be fixed is determined depending on the area in the stretchable sheet 10 where stretchability is desired. However, as shown in FIG. 6A, if the distance Dj between the pair of joints jP in the longitudinal direction is relatively wide and is equal to or larger than the diameter D14 of the thread rubber 14 stretched when forming the joint j, the thread after cutting The rubber 14 easily slips between the joint pair jP. Furthermore, even if the distance Dj between the joint pair jP is narrower than the diameter D14 of the rubber thread 14 that is stretched when forming the joint j, if the stretching ratio of the rubber thread 14 is high, the rubber thread 14 will The contraction force after cutting is strong, and the rubber thread 14 easily slips through between the joint pair jP.

Therefore, even if it is desired to fix the cut end portion 14a of the rubber thread 14 with the first joint pair jP1, simply cutting the rubber thread 14 will cause the rubber thread 14 to The thread rubber 14 may slip between the joint pair jP1 and be fixed at the second joint pair jP2, or the thread rubber 14 may be fixed at the joint pair jP on one side in the lateral direction than the second joint pair jP2. may become fixed.

Therefore, in the present embodiment, when it is desired to fix the cut end portion 14a of the rubber thread 14 with the first joint pair jP1, in the step of cutting the rubber thread 14, from the cutting position Pc of the rubber thread 14 in the lateral direction to the second The rubber thread 14 is cut with a rubber thread regulating section 30 (regulating section) for regulating contraction and movement of the rubber thread 14 provided in at least a part of the range up to the other end P5 of the joint pair jP2. .

As shown in FIG. 3, the thread rubber regulating section 30 of the first embodiment controls the laminate 10' in which the thread rubber 14 is arranged between the first sheet part 11 and the second sheet part 12 in the thickness direction. Nip rollers 31 and 32 (nipping means) rotate while nipping. Note that the nip rollers 31 and 32 have lengths in the CD direction so that they can pinch the plurality of rubber threads 14 arranged in the CD direction (vertical direction) between the first sheet part 11 and the second sheet part 12. Use a roller. Further, the thread rubber regulating section is not limited to the nip rollers 31 and 32, and may be any nip means that rotates while sandwiching the laminate 10', and may be, for example, a pair of conveyor belts arranged opposite to each other. .

As shown in FIG. 9B, the first and second sheet parts 11 and 12 and the rubber thread 14 are pinched in the thickness direction between the nip rollers 31 and 32, and the contraction movement of the rubber thread 14 is regulated. Therefore, when the thread rubber regulation part 30 is not provided, immediately after cutting the thread rubber 14, the entire thread rubber 14 located on one side in the lateral direction from the cutting position Pc contracts vigorously, and the thread rubber 14 In contrast, in this embodiment, it is easier to slip between the first joint pair jP1, but in the present embodiment, the thread rubber regulating part 30 located in the above range (Pc to P5) is shrinkage of the rubber thread 14 on the side) can be suppressed. Therefore, the length of the rubber thread 14 that contracts from the cutting position Pc to one side in the lateral direction can be shortened, and the shrinkage force of the rubber thread 14 can be weakened. Can prevent slippage.

On the other hand, since the rubber thread 14 from the cutting position Pc to the rubber thread regulation part 30 contracts, the diameter of the cut end 14a of the rubber thread 14 can be increased. Therefore, as shown in FIG. 7B, the cut end portion 14a of the rubber thread 14 having a thicker diameter is less likely to slip through between the first joint pair jP1 and is easily fixed by the first joint pair jP1.

Specifically, it is assumed that the rubber thread 14 is cut while the laminate 10' is being transported with one side in the lateral direction being the downstream side in the transport direction. In this case, as shown in the right view of FIG. 8A, immediately after the rubber thread 14 is cut, the cut end 14a of the rubber thread 14 contracts to the upstream end of the rubber thread regulating portion 30 and becomes thicker. Thereafter, as shown in the right view of FIG. 8B, the cut end 14a of the rubber thread 14 passes between the nip rollers 31 and 32. Then, as shown in the right view of FIG. 8C, after the cut end 14a of the rubber thread 14 is separated from the nip rollers 31 and 32 and released, the cut end 14a of the rubber thread 14 reaches the first joint jP1. It further contracts and becomes thicker, and is fixed at the first joint pair jP1.

As described above, if the distance Dj between the joint pair jP in the longitudinal direction is greater than or equal to the diameter D14 of the rubber thread 14 in the stretched state, or if the stretching magnification of the rubber thread 14 is high, the rubber thread 14 may Even if the cut end portion 14a of the rubber thread 14 easily slips through the gap, according to the manufacturing method of this embodiment, the cut end portion 14a of the rubber thread 14 is easily fixed at the desired joint pair jP. Therefore, the stretchable region of the stretchable sheet 10 can be prevented from becoming narrow, and stretchability can be developed in a desired region of the stretchable sheet 10.

Although the first joint pair jP1 located immediately adjacent to the cutting position Pc of the rubber thread 14 is the joint pair jP that fixes the cut end 14a of the rubber thread 14, the present invention is not limited thereto. That is, the N-th (N≧2) joint pair jP from the cutting position Pc of the rubber thread 14 is the joint pair jP that fixes the cut end 14a of the rubber thread 14 (the first joint pair jP1 of the present invention). ).

Moreover, the same can be said about the other side in the lateral direction (the upstream side in the conveyance direction) of the cutting position of the rubber thread 14. For example, as shown in FIG. 7A, the pair of joints located on the other side in the lateral direction from the cutting position Pc of the rubber thread 14 is defined as the third pair of joints jP3, and Let us assume that a pair of joints adjacent to the third pair of joints jP3 on the other side is a fourth pair of joints jP4, and that it is desired to fix the cut end 14b of the rubber thread 14 with the third pair of joints jP3. In that case, the rubber thread regulating portion 30 may be provided in at least a portion of the range from the cutting position Pc of the rubber thread 14 in the lateral direction to one end P10 of the fourth joint pair jP4.

Therefore, in the stretchable sheet manufacturing apparatus 20 shown in FIG. 3, thread rubber regulating sections 30 are provided on the downstream and upstream sides of the cutter roller 26 and the receiving roller 27, respectively. However, the manufacturing apparatus is not limited to this, and may be a manufacturing apparatus in which the thread rubber regulating section 30 is provided only on one side of the downstream side and the upstream side.

Further, on the upstream side of the cutting position Pc of the rubber thread 14, as shown in the left side view of FIG. It contracts and becomes thicker to the side edges. Thereafter, as shown in the left side diagrams of FIGS. 8B and 8C, the rubber thread 14 separated from the rubber thread regulating section 30 gradually contracts, and the cut end 14b of the rubber thread 14 becomes even thicker, and finally the thread It is fixed at a third pair of joints jP3 located away from the rubber regulating part 30.

Further, even if the thread rubber regulating section 30 is provided on one side in the lateral direction from the end P5 on the other side in the lateral direction of the second joint pair jP2, when the thread rubber regulating section 30 is not provided; In comparison, slipping of the rubber thread 14 from the first joint pair jP1 can be suppressed. However, if the thread rubber regulation part 30 is too far away from the first joint pair jP1, the length of the thread rubber 14 from the cutting position Pc to the thread rubber regulation part 30 becomes long, and the shrinkage force of the thread rubber 14 is reduced. Since it is not weakened, there is a risk that the rubber thread 14 may slip through the first joint pair jP1. Therefore, in this embodiment, the thread rubber regulating section 30 is arranged in the above range (Pc to P5).

More preferably, as shown in FIG. 9A, the thread rubber regulating portion 30 is provided in a range that includes at least part of the portions P2 to P3 where the first joint pair jP1 is located in the lateral direction. (The thread rubber regulating portion 30 is preferably provided in a range that includes at least part of the portions P7 to P8 where the third joint pair jP3 in FIG. 7A is located.)

In this case, when the rubber thread 14 is cut, the shrinkage movement of the rubber thread 14 located between the first pair of joints jP1 is regulated, so that the rubber thread 14 is prevented from slipping through the first pair of joints jP1. This can be suppressed more reliably. Furthermore, the amount of shrinkage of the rubber thread 14 on one side in the lateral direction relative to the first joint pair jP1 is suppressed during the period after the rubber thread 14 is cut until it is fixed at the first joint pair jP1. I can do it. Therefore, the rubber thread 14 is fixed in a state where the elongation magnification of the rubber thread 14 that has been elongated when forming the joint part j is generally maintained. Therefore, a stretchable sheet 10 having a desired stretching force can be manufactured.

Furthermore, as shown in FIG. 9A, in the lateral direction, there is a range Pc to P1 on the cutting position Pc side of the center P1 between the cutting position Pc of the rubber thread 14 and the other end P2 of the first joint pair jP1. , it is preferable that the thread rubber regulating part 30 is not provided (in the range Pc to P6 on the cutting position Pc side from the center P6 between the cutting position Pc in FIG. 7A and one side end P7 of the third joint pair jP3). , it is preferable that the thread rubber regulating section 30 is not provided).

By doing so, the length of the rubber thread 14 closer to the cutting position Pc than the rubber thread regulating portion 30 can be ensured appropriately, and the cut end portion 14a of the rubber thread 14 can be contracted and made thicker. Therefore, slippage of the rubber thread 14 from the first joint pair jP1 can be more reliably suppressed.

(Modified example: Arrangement of thread rubber regulation part 30)
10A to 10C and FIGS. 11A to 11B are diagrams showing modified examples of the arrangement of the thread rubber regulating section 30.

As shown in FIG. 10A, in the lateral direction, the thread rubber regulation is applied to at least a portion of the range from one end P3 of the first joint pair jP1 to the other end P5 of the second joint pair jP2. 30 may be provided (at least a portion of the range from the other end P8 of the third joint pair jP3 to the one end P10 of the fourth joint pair jP4 in FIG. 7A). A rubber regulating part 30 may be provided.)

In this case as well, the shrinkage of the rubber thread 14 on the side opposite to the cutting position Pc from the thread rubber regulating portion 30 can be suppressed, and the shrinkage force of the rubber thread 14 from the cutting position Pc can be weakened. Therefore, slippage of the rubber thread 14 from the first joint pair jP1 can be suppressed. On the other hand, since the rubber thread 14 closer to the cutting position Pc than the thread rubber regulating portion 30 can be contracted and made thicker, the cut end portion 14a of the rubber thread 14 can be easily fixed at the first joint pair jP1.

Further, in the case of FIG. 10A, the rubber thread regulating portion 30 is provided in a region where the rubber thread 14 is left to expand and contract. Therefore, between the time the thread rubber 14 is cut and the time it is fixed at the first joint pair jP1, the thread rubber 14 in the area where the thread rubber 14 is left to expand and contract (more specifically, the area of the thread rubber 14 that is more anti-cut than the thread rubber regulation part 30 The rubber thread 14) on the side of position Pc is difficult to shrink, and the elongation magnification of the rubber thread 14 is generally maintained. Therefore, a stretchable sheet 10 having a desired stretching force can be manufactured.

Furthermore, as shown in FIG. 10B, in the lateral direction, the first It is preferable that the thread rubber regulating portion 30 is provided in a range including at least part of the parts P3 to P4 on the side of the joint pair jP1 (the end P8 on the other side of the third joint pair jP3 in FIG. 7A The thread rubber regulating portion 30 is provided in a range including at least part of the portions P8 to P9 on the third joint pair jP3 side, from the center P9 between the fourth joint pair jP4 and one end P10. (Good to have).

By doing so, the shrinkage of the rubber thread 14 is regulated at a position close to the first pair of joints jP1, so that slippage of the rubber thread 14 from the first pair of joints jP1 can be more reliably suppressed. Further, contraction of the rubber thread 14 in a larger portion of the region where the rubber thread 14 remains elastic can be suppressed, and the elongation magnification of the rubber thread 14 can be maintained.

Further, as shown in FIG. 10C, the thread rubber regulating portion 30 may be provided in at least a portion of the range from the cutting position Pc to the other end P2 of the first joint pair jP1 in the lateral direction. (The thread rubber regulating portion 30 may be provided in at least a portion of the range from the cutting position Pc to one end P7 of the third joint pair jP3 in FIG. 7A). That is, the rubber thread regulating portion 30 may be provided in a region where the rubber thread 14 comes off after the rubber thread 14 is cut.

In this case as well, the shrinkage of the rubber thread 14 on the side opposite to the cutting position Pc from the thread rubber regulating portion 30 can be suppressed, and the shrinkage force of the rubber thread 14 from the cutting position Pc can be weakened. Therefore, slippage of the rubber thread 14 from the first joint pair jP1 can be suppressed. On the other hand, since the rubber thread 14 closer to the cutting position Pc than the thread rubber regulating portion 30 can be contracted and made thicker, the cut end portion 14a of the rubber thread 14 can be easily fixed at the first joint pair jP1.

More preferably, the thread rubber regulating portion is provided in a range Pc to P1 on the cutting position Pc side with respect to the center P1 between the cutting position Pc of the thread rubber 14 and the other side end P2 of the first joint pair jP1 in the lateral direction. 30 is preferably not provided (the range Pc to P6 on the cutting position Pc side of the center P6 between the cutting position Pc and one end P7 of the third joint pair jP3 in FIG. 30 is not provided).

By doing so, the length of the rubber thread 14 closer to the cutting position Pc than the rubber thread regulating portion 30 can be ensured appropriately, and the cut end portion 14a of the rubber thread 14 can be contracted and made thicker. Therefore, slippage of the rubber thread 14 from the first joint pair jP1 can be more reliably suppressed.

Furthermore, as described above (see FIGS. 8A to 8C), on the upstream side of the cutting position Pc of the rubber thread 14, the rubber thread 14 that is separated from the rubber thread regulation part 30 gradually contracts, and the rubber thread 14 gradually contracts. The cut ends 14b are fixed at the third joint pair jP. Therefore, shrinkage of the rubber thread 14 on the upstream side of the third joint pair jP3 can be suppressed, and the elongation magnification of the rubber thread 14 can be easily maintained.

On the other hand, on the downstream side of the cutting position Pc of the rubber thread 14, as shown in FIG. 8C, after the cut end 14a of the rubber thread 14 is separated from the rubber thread regulation part 30, Before reaching the first joint pair jP1, the entire rubber thread 14 contracts, and the elongation magnification of the rubber thread 14 decreases slightly. In particular, as shown in FIG. 10C, when the thread rubber regulating section 30 is provided from Pc to P2 from the cutting position Pc to the first joint pair jP1, the cut end 14a of the thread rubber 14 is connected to the first joint pair jP1. The time it takes to reach part pair jP1 is relatively long.

Therefore, as shown in FIG. 11A, a first thread rubber regulating portion 30A is provided in a part of the range from the cutting position Pc to the other end P2 of the first joint pair jP1 in the lateral direction, and The second thread rubber regulating portion 30B may be provided in a part of the range from one end P3 of the first joint pair jP1 to the other end P5 of the second joint pair jP2 in the direction. The first rubber thread regulating section 30A releases the restriction on the shrinkage movement of the rubber thread 14 before the second rubber thread regulating section 30B.

By doing so, as shown in FIG. 11B, after the cut end 14a of the rubber thread 14 is separated from the rubber thread regulating section 30, the cut end 14a of the rubber thread 14 reaches the first joint pair jP1. Until then, the shrinkage of the rubber thread 14 on the downstream side of the second rubber thread regulating portion 30B can be suppressed, and the elongation magnification of the rubber thread 14 can be easily maintained.

<<Second embodiment>>
FIG. 12 is a schematic cross-sectional view of the thread rubber regulating section 30 in the second embodiment. In the second embodiment, the receiving roller 27 that transports the laminated body 10' in which the thread rubber 14 is arranged between the first sheet part 11 and the second sheet part 12 while winding the same is used as the thread rubber regulating part 30.

Also, in the second embodiment, similarly to the first embodiment (see FIG. 7A), an example is given in which the cut end of the rubber thread 14 is fixed by the first joint pair jP1 (third joint jP3). Listed below. In this case, as shown in FIG. It is preferable to cut the rubber thread 14 while it is wrapped around the outer peripheral surface (Similarly, the rubber thread 14 is cut in the range from the cutting position Pc of the rubber thread 14 to the downstream end P10 of the fourth joint pair jP4 of the laminate 10'. It is preferable to cut the rubber thread 14 with at least a portion thereof wrapped around the outer peripheral surface of the receiving roller 27).

The rubber thread 14 wound around the outer peripheral surface (curved surface) of the receiving roller 27 is in close contact with the outer peripheral surface of the receiving roller 27. Moreover, since the first sheet part 11 and the second sheet part 12 with the thread rubber 14 interposed therebetween are also in close contact with the outer peripheral surface of the receiving roller 27, the thread rubber 14 is sandwiched between the first sheet part 11 and the second sheet part. ing. Therefore, after the rubber thread 14 is cut, the rubber thread 14 contracts slowly, and the contraction movement of the rubber thread 14 is restricted. Therefore, it takes a long time after the rubber thread 14 is cut until the cut end of the rubber thread 14 reaches the first joint pair jP1. Therefore, when the cut end of the rubber thread 14 reaches the first joint pair jP1, the diameter of the rubber thread 14 has become thicker, and the cut end of the rubber thread 14 from the first joint pair jP1 The cut ends of the rubber thread 14 can be easily fixed at a desired joint pair jP.

Further, by using the receiving roller 27, which is a part of the device for cutting the thread rubber 14, also as the thread rubber regulating section 30, the device configuration can be simplified.

However, it is not limited to the above. For example, as shown in FIG. 3, the laminate 10' is passed linearly between the cutter roller 26 and the receiving roller 27, and the laminate 10' is placed on the upstream or downstream side of the cutter roller 26 and the receiving roller 27. A roller for wrapping may be provided. Further, the roller around which the laminate 10' is wound is not limited to a roller having a smooth outer circumferential surface, but may be a roller having an uneven outer circumferential surface or a roller having a polygonal cross-sectional shape.

Further, the length of the laminate 10' wound around the receiving roller 27 may be shorter or longer than the length Pc to P5 from the cutting position Pc to the second joint pair jP2 (from the cutting position Pc to the fourth joint pair jP4). may be shorter or longer than the length Pc to P10).

Note that the cutter blade 261 is not limited to a rotary type provided on the cutter roller 26. For example, it may be a cutter blade that moves in the vertical direction (thickness direction of the laminate 10') with respect to the receiving roller 27 and pinches and cuts the rubber thread 14 together with the receiving roller 27. Furthermore, in the case where the receiving roller 27 does not restrict the contraction movement of the rubber thread 14 as in the second embodiment, the receiving portion (receiving blade) of the cutter blade 261 is not limited to a rotary type. That is, the cutting device for the rubber thread 14 may be any device that can cut the rubber thread 14 by sandwiching it between a cutter blade and a receiving portion.

<<Third Embodiment>>
FIG. 13 is a plan view of the stretchable sheet 10 of the third embodiment. FIG. 14 is a schematic cross-sectional view of a manufacturing apparatus 20 for a stretchable sheet 10 in the third embodiment. In the third embodiment, before cutting the rubber thread 14, a seal portion 43 is formed as the rubber thread regulating portion 30.

The seal portion 43 is a portion where at least the first sheet portion 11 and the second sheet portion 12 are pressed together. Examples of crimping include heat sealing (thermal welding), crimping without heating, and ultrasonic welding.

In the third embodiment, as in the first embodiment (see FIG. 7A), an example will be exemplified in which the cut end of the rubber thread 14 is fixed by the first joint pair jP1 (third joint jP3). . In this case, as shown in FIG. 13, it is preferable to form a seal portion 43 in at least a portion of the range from the cutting position Pc of the rubber thread 14 to the other end P5 in the lateral direction of the second joint pair jP2 ( Similarly, the seal portion 43 may be formed in at least a portion of the range from the cutting position Pc to the end P10 on one side in the lateral direction of the fourth joint pair jP4).
Preferably, the seal portion 43 is preferably formed in at least a portion of the range from the end P2 on the other side in the lateral direction of the first joint pair jP1 to the end P5 on the other side in the lateral direction of the second joint pair jP2. (Similarly, if the seal portion 43 is formed in at least a portion of the range from the end P7 on one side in the lateral direction of the third pair of joints jP3 to the end P10 on the one side in the lateral direction of the fourth joint pair jP4 good).

For this purpose, in the manufacturing apparatus 20 of the third embodiment, a sealing device 40 is provided between the ultrasonic welding device 22, the cutter roller 26, and the receiving roller 27, as shown in FIG. The sealing device 40 is a pair of rollers arranged opposite to each other, one roller 41 is a roller having a convex portion on its outer peripheral surface corresponding to the formation position of the seal portion 43, and the other roller 42 is a roller having a convex portion corresponding to the formation position of the seal portion 43. An example of this is a roller that receives the part with a smooth outer circumferential surface.

In the region where the seal portion 43 is formed in the lateral direction, the first sheet portion 11 and the second sheet portion 12 are in close contact with each other. Therefore, the rubber thread 14 located therebetween is sandwiched between the first sheet part 11 and the second sheet part 12, and the contraction movement of the rubber thread 14 is regulated. Therefore, the shrinkage of the rubber thread 14 on the side opposite to the cutting position Pc from the seal portion 43 can be suppressed, and the shrinkage force of the rubber thread 14 from the cutting position Pc can be weakened. Therefore, slippage of the rubber thread 14 from the first joint pair jP1 can be suppressed. On the other hand, since the rubber thread 14 closer to the cutting position Pc than the seal portion 43 can be contracted and made thicker, the cut end 14a of the rubber thread 14 can be easily fixed at the first joint pair jP1.

Note that the seal portion 43 shown in FIG. 13 is exemplified as a seal portion in which the entire surface is crimped over a long range in the vertical direction, and the rubber thread 14 is also crimped together with the first sheet portion 11 and the second sheet portion 12. , the pattern of the seal portion 43 is not limited to this. For example, it may be a pattern in which a plurality of seal parts are formed discretely, or a pattern in which a seal part is formed in a position where the rubber thread 14 is not present, and only the first sheet part and the second sheet part are crimped. You can also

In addition, in the elastic sheet 10, when the first sheet part 11 and the second sheet part 12 are also cut and separated together with the thread rubber 14, the ends of the first sheet part 11 and the second sheet part 12 (cut position) becomes the cutting position (predetermined position in the lateral direction) of the rubber thread 14. On the other hand, when only the rubber thread 14 is cut and separated, the position of the cut mark on the rubber thread 14 becomes the cutting position of the rubber thread 14.

Further, in the region where the seal portion 43 is formed, the fiber density of the first sheet portion 11 and the second sheet portion 12 increases. Therefore, in the elastic sheet 10, when the ends of the rubber threads 14 are fixed at the first joint pair jP1, from the cutting position Pc of the rubber thread 14 to the other side in the lateral direction of the second joint pair jP2. A high-density region 43 is provided in at least a portion of the range up to the end P5.

The high-density region 43 is a region where the density of the first sheet portion 11 and the second sheet portion 12 is higher than the density of the first sheet portion 11 and the second sheet portion 12 outside the range Pc to P5. . Note that the comparison of densities can be performed using a well-known method. For example, comparison can be made based on images of cross sections of the first sheet part 11 and the second sheet part 12 cut in the thickness direction, enlarged using an electron microscope or the like.

<<Other embodiments>>
The rubber thread regulating section is not limited to those exemplified in the first to third embodiments, and may be any member that can regulate the shrinkage movement of the rubber thread 14.
For example, a device in which a convex portion is provided on the outer peripheral surface of at least one of the cutter roller 26 and the receiving roller 27 may be used as the thread rubber regulating section. This convex portion is provided immediately upstream or downstream of the cutter blade 261, and when the cutter blade 261 cuts the rubber thread 14, the convex portion and the outer peripheral surface of the roller facing the convex portion , the second sheet parts 11 and 12, and the rubber thread 14 are pressed together. By doing so, it is possible to restrict the shrinkage movement of the rubber thread 14 located in the convex portion.

Alternatively, a suction device that faces the cutter roller 26 and suctions the first and second sheet portions 11 and 12 while supporting and conveying the laminate 10' may be used as the thread rubber regulating section. Since the first and second sheet parts 11 and 12 are in close contact with the suction device and the rubber thread 14 is sandwiched between the first sheet part 11 and the second sheet part 12, contraction and movement of the rubber thread 14 can be restricted.

Although the embodiments of the present invention have been described above, the above-described embodiments are intended to facilitate understanding of the present invention, and are not intended to be interpreted as limiting the present invention. Further, the present invention can be modified and improved without departing from the spirit thereof, and it goes without saying that the present invention includes equivalents thereof.

10 stretch sheet, 10' laminate,
11 first sheet part, 12 second sheet part, 14 rubber thread,
20 Stretchable sheet manufacturing device, 21 Conveyance roller group (arrangement section),
22 Ultrasonic welding device (joint forming part),
23 anvil roller, 24 horn roller,
25 discharge roller,
26 cutter roller (cutting part), 261 cutter blade,
27 Receiving roller (cutting part, regulating part),
30 Thread rubber regulation department (regulation department),
30A first thread rubber regulation part (first regulation part),
30B second thread rubber regulation part (second regulation part),
31, 32 nip roller (nip means),
40 Seal portion forming device, 43 Seal portion, high density region (regulating portion),
j junction, jP junction pair,
jP1 first joint pair, jP2 second joint pair

Claims (9)

A method for manufacturing a stretchable sheet having longitudinal and transverse directions, the method comprising:
arranging the rubber thread stretched in the lateral direction between the first sheet portion and the second sheet portion;
Pressing the first sheet part and the second sheet part to form a plurality of joint parts joining each other;
cutting the rubber thread,
The plurality of joint portions have a plurality of joint portion pairs located on both sides of the thread rubber in the longitudinal direction and spaced apart in the horizontal direction,
After the cutting step, the contracted rubber thread is sandwiched between the pair of joint parts, and the lateral position of the rubber thread is regulated;
The plurality of pairs of joints include a first pair of joints located on one side in the lateral direction relative to the cutting position of the rubber thread, and a pair of joints located on one side in the lateral direction of the first pair of joints. having a first pair of joints and a second pair of adjacent joints,
In the cutting step, a regulating portion for regulating shrinkage movement of the rubber thread is provided in at least a part of the range from the cutting position to the other end of the second joint pair in the lateral direction. A method for producing a stretchable sheet in which the rubber thread is cut in a state in which the rubber thread is cut,
In the step of forming the joint, forming the joint using an anvil roller and a horn roller that are arranged opposite to each other,
In the cutting step, the rubber thread is cut using a cutter roller and a receiving roller that are arranged opposite to each other on the downstream side of the anvil roller and the horn roller in the conveying direction,
The regulating section is a pair of nip rollers that rotate while sandwiching a laminate in which the rubber thread is arranged between the first sheet section and the second sheet section,
A method for manufacturing a stretchable sheet , characterized in that each of the pair of nip rollers is a different roller from the receiving roller . A method for manufacturing a stretchable sheet according to claim 1, comprising:
A method for manufacturing a stretchable sheet, characterized in that, in the lateral direction, the regulating portion is provided in a range that includes at least a part of a portion where the first joint pair is located. A method for manufacturing a stretchable sheet according to claim 2, comprising:
In the lateral direction, the restricting portion is not provided in a range closer to the cutting position than the center between the cutting position and the other end of the first joint pair. Method of manufacturing sheets. A method for manufacturing a stretchable sheet according to claim 1, comprising:
The regulating portion is provided in at least a portion of the range from one end of the first pair of joints to the other end of the second pair of joints in the lateral direction. A method for manufacturing a stretchable sheet. A method for manufacturing a stretchable sheet according to claim 4, comprising:
In the lateral direction, at least a portion of the portion on the opposite side of the first joint portion is further from the center between one end of the first pair of joint portions and the other end of the second pair of joint portions. A method for manufacturing a stretchable sheet, characterized in that the regulating portion is provided in a range including. A method for manufacturing a stretchable sheet according to claim 1, comprising:
The method for manufacturing a stretchable sheet, characterized in that the regulating portion is provided in at least a part of the range from the cutting position to the other end of the first joint pair in the lateral direction. A method for manufacturing a stretchable sheet according to claim 1, comprising:
While the laminate in which the rubber thread is arranged between the first sheet part and the second sheet part is conveyed to one side in the lateral direction, the rubber thread is cut;
The restriction portion includes a first restriction portion provided in a part of the range from the cutting position to the other end of the first joint pair in the lateral direction; a second regulating portion provided in a part of the range from one end of the pair of joints to the other end of the second pair of joints,
A method for manufacturing a stretchable sheet, characterized in that the first regulating section releases the regulation of shrinkage movement of the rubber thread before the second regulating section. A method for manufacturing a stretchable sheet according to any one of claims 1 to 7 , comprising:
A method for manufacturing a stretchable sheet, wherein a distance between the pair of joints in the longitudinal direction is equal to or larger than a diameter of the rubber thread in the stretched state. An apparatus for manufacturing a stretchable sheet having longitudinal and transverse directions,
an arrangement section for arranging the rubber thread stretched in the lateral direction between the first sheet section and the second sheet section;
a joint forming part that forms a plurality of joint parts that press the first sheet part and the second sheet part to join each other;
a cutting section that cuts the rubber thread;
The plurality of joint portions have a plurality of joint portion pairs located on both sides of the thread rubber in the longitudinal direction and spaced apart in the horizontal direction,
After the cutting step, the contracted rubber thread is sandwiched between the pair of joint parts, and the lateral position of the rubber thread is regulated;
The plurality of pairs of joints include a first pair of joints located on one side in the lateral direction relative to the cutting position of the rubber thread, and a pair of joints located on one side in the lateral direction of the first pair of joints. having a first pair of joints and a second pair of adjacent joints,
In the cutting step, a regulating portion for regulating shrinkage movement of the rubber thread is provided in at least a part of the range from the cutting position to the other end of the second joint pair in the lateral direction. A stretchable sheet manufacturing device that cuts the rubber thread in a state where
The joint forming section forms the joint using an anvil roller and a horn roller that are arranged opposite to each other,
The cutting section cuts the rubber thread using a cutter roller and a receiver roller that are arranged opposite to each other on the downstream side of the anvil roller and the horn roller in the conveying direction,
The regulating portion is a pair of nip rollers that rotate while sandwiching a laminate in which the rubber thread is arranged between the first sheet portion and the second sheet portion,
An apparatus for producing a stretchable sheet , wherein each of the pair of nip rollers is a different roller from the receiving roller .

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