JP6102906B2 - Pants-type disposable diaper manufacturing method - Google Patents

Description

  The present invention relates to a disposable diaper that is attached to a wearer's crotch and absorbs and holds a liquid such as urine. More specifically, the disposable diaper of the present invention is characterized in that a part of the elastic elastic member disposed around the belly of the diaper is substantially free of oil.

  Conventionally, a pants-type disposable diaper that is divided into a front body that contacts the wearer's abdomen, a back body that contacts the back of the wearer, and a crotch region positioned therebetween is known. A pants-type disposable diaper has an absorbent main body arranged from the front to the back, mainly in the crotch region. The absorbent main body generally includes a top sheet, a back sheet, and an absorber interposed between these sheets. In a general disposable diaper, the absorber is covered with a top sheet made of a liquid permeable material from the surface side in contact with the wearer's skin, and formed from a liquid impermeable material from the opposite back side. It is covered with. For this reason, for example, body fluid excreted by the wearer passes through the top sheet and is absorbed by the absorbent body, and leakage to the outside is prevented by the back sheet.

  In addition, as a pants-type disposable diaper, the outer body for holding the absorbent main body is a type in which the outer body is connected in a series from the front body to the rear body, or the outer body is a type in which the front body and the back body are separated. Things are known. In the pants-type disposable diaper, the front and back bodies are joined at opposite ends by side seal portions provided at both end portions in the width direction of the disposable diaper.

  Here, more specifically, a pants-type disposable diaper in which the exterior body is separated at the front body and the back body will be described as an example. For example, as a pants-type disposable diaper, an absorbent main body and a front body outer body and a rear body outer body for holding the absorbent body around the waist of the wearer are separately formed. Disposable diapers (so-called cross-linked disposable diapers) are known (for example, Patent Document 1). In the cross-linked disposable diaper, one end side in the length direction of the absorbent main body is fixed to the front body exterior body, and the other end side in the length direction of the absorbent main body is fixed to the rear body exterior body. For this reason, an absorptive main body becomes a structure bridge | crosslinked between a front body exterior body and a back body exterior body. And a pants-type disposable diaper is formed by joining the front body exterior body and the back body exterior body in the side seal part provided in the both-sides edge part in the state in which the absorptive main body was bridge | crosslinked. The wearer can wear the disposable diaper formed in a pants shape by inserting both legs. In such a cross-linked disposable diaper, the opening around the leg is wide open, so that the wearer can move both legs relatively freely even when the disposable diaper is worn. There is an advantage.

  In general, a plurality of elastic elastic members are fixed in an expanded state along the abdomen and waist around the front and back of a pants-type disposable diaper. Since the elastic elastic member contracts, gathers are formed around the stomach and waist of the disposable diaper, so that the fit of the disposable diaper is improved. Various types of elastic elastic members can be attached to the disposable diaper. For example, those disclosed in Patent Document 2 and Patent Document 3 are known as examples of the elastic elastic members.

  Also, the front body and back body of a pants-type disposable diaper generally have a main body region with side seal portions formed on both sides in the width direction, and an extended region extending from the main body region to the crotch region side. Exists (see Patent Document 1). A plurality of elastic elastic members are fixed to the main body region and the extension region in an extended state. For example, the elastic stretchable member is fixed by being sandwiched between two sheet members constituting the stomach of the disposable diaper. In this way, in the front body and the back body, the elastic stretch members are fixed to the main body region and the extension region, respectively, so that the adhesion between the outer body and the wearer's body is increased, and urine leakage is prevented. There is an advantage that it can be effectively prevented and the appearance of the diaper when worn can be improved.

JP 2013-123447 A Japanese Patent Laid-Open No. 10-152264 JP 2000-289931 A

  However, among the elastic elastic members fixed to the front and back bodies, the elastic elastic member fixed to the extension region is compared to the elastic elastic member fixed to the main body region when the disposable diaper is worn or manufactured. At the stage, the problem of being easily detached from the sheet member constituting the diaper was revealed.

  That is, side seal portions are formed on the left and right sides in the width direction in the main body region of the front body and the back body. Moreover, the elastic elastic member arrange | positioned in a main body area | region generally remains connected without being cut | disconnected until the final stage in the manufacturing process of a disposable diaper in general. For this reason, it is considered that the elastic elastic member fixed to the main body region is relatively difficult to come off due to the influence of the joint in the side seal portion. On the other hand, side seal portions do not exist on the left and right sides in the width direction in the extension regions of the front body and the back body. For this reason, in the extension area | region, compared with a main body area | region, the joining strength of an elastic elastic member and a sheet | seat member is comparatively weak. Therefore, the elastic elastic member fixed to the extension area is gradually peeled off from the sheet member under the influence of its own contractive force when wearing the diaper or at the manufacturing stage. There has been a case where the sheet member comes off. In other words, in the extended region, if the elastic elastic member is removed from between the sheet members constituting the diaper, there is a situation where the gathers originally formed by the elastic elastic member being fixed do not function. In this way, if the elastic elastic member is removed in the extension region of the front body and the back body, the extension region will not be in close contact with the wearer's body, and it will be in a state of fluttering, making the diaper look bad. The problem of becoming occurred.

  For this reason, at present, there is a demand for a technique capable of ascertaining and improving the cause of the elastic stretchable member being easily removed, particularly in the extension region of the front body and the back body.

  Therefore, the inventor of the present invention, as a result of repeated trial and error in order to investigate the cause of the problems of the above-described conventional invention, results in the oil agent adhering to the elastic expansion / contraction member between the elastic expansion / contraction member and the sheet member. It was found that this was one of the causes of defects that weakened the bonding strength. That is, the present inventor predicts the bonding strength between the elastic expansion / contraction member and the sheet member by using an elastic expansion / contraction member fixed to the extension region of the front body and the back body to which the oil agent is not substantially attached. As a result, it has been found that the elastic elastic member can be prevented from coming off.

  Explaining in detail, as described in Patent Document 2 and Patent Document 3, a general elastic stretchable member is used as a fixing member in a continuous state in the length direction before being attached to a disposable diaper. It is a wound silk thread. As described above, a general elastic elastic member is delivered from the manufacturer of the elastic member to the manufacturer of the disposable diaper in the form of a thread body. In the manufacturing process of the disposable diaper, a hot-melt adhesive or the like is applied to the stretched elastic stretchable member while pulling out the elastic stretchable member of a necessary length from the thread body and stretching it to a predetermined elongation rate. Apply. Thereafter, the elastic stretchable member coated with the adhesive is fixed to the sheet member constituting the diaper and cut into a required length. Thus, in the manufacturing process of a diaper, it is supposed that an elastic elastic member is attached to a disposable diaper.

  Here, as described in Patent Document 2 and Patent Document 3, a predetermined amount of oil is applied to the surface of a general elastic elastic member. The oil applied to the elastic elastic member is also called a finishing oil. In the manufacturing stage of the elastic stretchable member, this finishing oil agent is attached to the surface of the elastic stretchable member, and then the winding thread body is formed by a fixing member or the like. Thus, it is said that by attaching an oil agent to the elastic stretchable member, the elastic stretchable member can be prevented from being entangled when the elastic stretchable member is pulled out from the string in the manufacturing process of the disposable diaper.

However, it has been found that the oil agent attached to the elastic expansion / contraction member causes the adhesive strength between the elastic expansion / contraction member and the hot melt adhesive to deteriorate. That is, if the oil agent adheres to the surface, the hot melt adhesive hardly remains on the surface of the elastic elastic member, and as a result, the bonding strength between the elastic elastic member and the diaper sheet member decreases. Therefore, in the present invention, an elastic expansion / contraction member to which an oil agent is not substantially attached is used in particular in the extension region of the front body and the back body where the elastic expansion / contraction member is considered to be easily removed. Thereby, in the extension area | region of a front body and a back body, since the joining strength of a sheet | seat member and an elastic expansion-contraction member increases, this omission of this elastic expansion-contraction member can be prevented. Then, the present inventor has come up with the idea that the problems of the prior art can be solved based on such knowledge, and completed the present invention.
More specifically, the present invention has the following configuration.

The present invention relates to a so-called pants-type disposable diaper.
That is, the disposable diaper of the present invention has a front body that contacts the wearer's abdomen, a back body that contacts the back of the wearer, and a crotch region located between the front body and the back body. The front body and the back body are joined at opposite end portions of the side seal portions 4 provided at both end portions in the width direction of the disposable diaper.
Here, the front body and the back body have main body regions 11 and 21 and extension regions 12 and 22, respectively. The main body regions 11 and 21 are regions where the side seal portions 4 are formed at both end portions in the width direction. The extension regions 12 and 22 are regions having shapes extending from the main body regions 11 and 21 toward the crotch region and gradually becoming narrower as the width in the width direction approaches the crotch region.
In the main body regions 11 and 21, one or a plurality of first elastic members 13 and 23 are arranged in an extended state along the width direction. In the extended regions 12 and 22, one or a plurality of second elastic members 14 and 24 are arranged in an extended state along the width direction.
And as for the 2nd expansion-contraction members 14 and 24, the oil agent adhesion amount is 0.1 weight% or less.

  As described above, in the present invention, the oil agent is not substantially attached to the second stretchable members 14 and 24 arranged in the extension regions 12 and 22 of the front body and the back body. Most preferably, the oil agent adhesion amount of the second elastic members 14, 24 is 0% by weight. In this way, by using a material that does not have an oil agent attached to the second elastic members 14 and 24, the bonding strength between the second elastic members 14 and 24 and the sheet member constituting the diaper is increased, and the second elastic members The members 14 and 24 can be prevented from being detached from the sheet member.

  In the disposable diaper of the present invention, it is preferable that the second elastic members 14 and 24 are manufactured without going through the step of attaching an oil agent. Here, the “step of attaching an oil agent” includes both a step of internally adding the oil agent to the elastic elastic member and a step of externally adding the oil agent to the elastic elastic member. That is, it is preferable that the second elastic members 14, 24 are not attached with an oil agent regardless of whether they are internally added or externally added.

  As described above, in the present invention, it is preferable to use, as the second elastic members 14 and 24, elastic elastic members that are manufactured without the step of attaching the oil agent. Thus, the effect of the present invention can be obtained by positively removing the elastic elastic member to which the oil agent is adhered and using the elastic elastic members to which the oil agent is not substantially attached as the second elastic members 14 and 24. Increase more.

  In the disposable diaper of the present invention, the second elastic members 14 and 24 are preferably thicker than the first elastic members 13 and 23. In other words, the second elastic members 14 and 24 preferably have a larger cross-sectional area than the first elastic members 13 and 23.

  As described above, by adopting an elastic elastic member that is thicker than the first elastic members 13 and 23 as the second elastic members 14 and 24, the surface area of the second elastic members 14 and 24 becomes relatively large. When the surface area of the second elastic members 14 and 24 is increased, the amount of adhesive such as hot melt is increased. For this reason, the joint strength of the 2nd elastic members 14 and 24 and the sheet member which constitutes a diaper improves, and as a result, the 2nd elastic members 14 and 24 become difficult to come off.

  In the disposable diaper of the present invention, it is preferable that the second elastic members 14 and 24 have a lower elongation rate than the first elastic members 13 and 23.

  As in the above configuration, the expansion rate when the second elastic members 14 and 24 are arranged in the extension regions 12 and 22 is larger than the elongation rate when the first elastic members 13 and 23 are arranged in the main body regions 11 and 21. Also, the bonding strength between the second elastic members 14 and 24 and the sheet member becomes relatively high. This prevents the second elastic members 14 and 24 from coming off.

  According to the present invention, it is possible to solve the problem that the elastic elastic member is easily removed in the extension regions of the front body and the back body.

FIG. 1 is a perspective view showing an appearance of a disposable diaper. FIG. 2 is a development view of the disposable diaper.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments described below, but includes those appropriately modified by those skilled in the art from the following embodiments.
Here, in the present specification, “A to B” means “A or more and B or less”.
In the present specification, the “length direction” of a disposable diaper or an absorbent main body basically means the direction connecting the front body side and the back body side (vertical direction in FIG. 2), and “width” The term “direction” basically means a direction (left-right direction in FIG. 2) orthogonal to the length direction.

  In the present specification, the contents of the present invention will be described in detail by taking as an example a pants-type disposable diaper in which the outer body for holding the absorbent main body is separated from the front body and the back body. However, the disposable diaper of the present invention is not limited to a type in which the outer body of the front body and the outer body of the rear body are separated, and can be applied to a type in which the outer body is connected in series from the front body to the back body. It is.

  FIG. 1 is a schematic diagram showing an example of a disposable diaper 100, and shows a state where the disposable diaper 100 is viewed from the front body exterior body 1 side. FIG. 2 is a development view of the disposable diaper 100 shown in FIG. 1, and shows a state where the disposable diaper 100 is viewed from a surface (skin facing surface) in contact with the wearer's skin. In FIG. 2, various sheet materials constituting the disposable diaper are transparently drawn in order to show the positional relationship of the elastic stretchable members arranged in various places.

  As shown in FIGS. 1 and 2, the disposable diaper 100 includes a front body exterior body 1, a rear body exterior body 2, and an absorbent main body 3. The front body exterior body 1 constitutes a front body that contacts the wearer's abdomen when worn, and the rear body exterior body 2 constitutes a back body that contacts the wearer's back when worn. The front body exterior body 1 and the back body exterior body 2 are separated from each other. The front body exterior body 1 and the back body exterior body 2 may be individually formed, or may be integrally formed and separated later. The absorbent main body 3 has one end side in the length direction fixed to the front body exterior body 1 and the other end side fixed to the rear body exterior body 2. For this reason, in this invention, as for the absorptive main body 3, the crotch region is not fixed to either the front body exterior body 1 or the back body exterior body 2. Thus, the absorptive main body 3 is in a state of being bridged between the front body exterior body 1 and the back body exterior body. As a means for fixing the absorbent main body 3 to the front body exterior body 1 and the back body exterior body 2, a known method can be used, for example, fixing using a hot melt adhesive or other fluid adhesive. It may be fixed to the method, or may be fixed by heat welding such as heat sealing or ultrasonic welding.

  Further, as shown in FIG. 1, the front body exterior body 1 and the back body exterior body 2 are joined to each other at the side seal portions 4 located on both side edges in the width direction, so that the front body exterior body 1 and the back body exterior body 1 are joined. The exterior body 2 is connected in an annular shape. For this reason, as shown in FIG. 1, a waist circumference opening 5 located around the wearer's waist when worn and a leg circumference opening 6 located around the wearer's leg when worn. In this way, a pants-type disposable diaper 100 is formed. The wearer puts both legs into the waist opening 5 so that the abdomen is in contact with the front body exterior body 1 and the back is in contact with the back body exterior body 2, and the respective legs are placed around the legs. By taking out from the opening part 6, the bridge | crosslinking type disposable diaper 100 can be mounted | worn.

  The front body exterior body 1 and the back body exterior body 2 are in contact with the wearer's abdomen and back, and absorbable between the front body exterior body 1 and the back body exterior body 2 when the disposable diaper 100 is worn. It is a member for suspending the main body 3.

  The front body exterior body 1 and the back body exterior body 2 have a pair of side seal portions 4 at the left and right side edges in the width direction of the diaper. The front body exterior body 1 and the back body exterior body 2 are joined at the pair of side seal portions 4 with the right and left side edges in the width direction of the diaper being overlapped with each other. The pair of side seal portions 4 extends in the length direction of the diaper and is linearly formed. In the side seal portion 4, the front body exterior body 1 and the back body exterior body 2 are joined by a known joining means such as hot emboss welding or ultrasonic emboss welding.

  As shown in FIG. 2, in the front body exterior body 1 and the back body exterior body 2, regions extending from the location where the pair of left and right side seal portions 4 exist to the diaper width direction are main body regions 11 and 21. Reference numeral 11 denotes a main body region (front-side main body region) of the front body exterior body 1, and reference numeral 21 denotes a main body region (rear-side main body region) of the rear body exterior body 2. As shown in FIG. 2, the main body regions 11 and 21 are rectangular regions having side seal portions 4 at both left and right end portions in the diaper width direction and positioned between the pair of side seal sides.

  Further, as shown in FIG. 2, in the front body exterior body 1 and the back body exterior body 2, regions extending from the main body regions 11 and 21 toward the crotch region 3 a are extended regions 12 and 22. Become. Reference numeral 12 denotes an extension region (front extension region) of the front body exterior body 1, and reference numeral 22 denotes an extension region (rear extension region) of the rear body exterior body 2. As shown in FIG. 2, the extension regions 12 and 22 are narrower in the diaper width direction than the main body regions 11 and 21, and the extension regions 12 and 22 have a crotch region 3a. It becomes narrower gradually toward the direction.

  More specifically, as shown in the developed view of FIG. 2, the front body exterior body 1 has a pair of both sides on which a long side 1a that is a side that becomes a waist circumference end and a pair of side seal portions 4 are formed. A shape having a side 1b, a short side 1c that is formed substantially parallel to the long side 1a and to which the absorbent main body 3 is fixed, and a pair of oblique sides 1d that connects both ends of the short side 1c and a pair of both sides 1b. It has become. In this case, a substantially rectangular region defined when one end of the pair of both sides 1b is connected by the long side 1a and the other end of the pair of both sides 1b is connected by a virtual line is the front body exterior. It becomes the front main body region 11 of the body 1. On the other hand, a substantially trapezoidal area defined when one end of the pair of hypotenuses 1d is connected by a short side 1c and the other end of the pair of hypotenuses 1d is connected by a virtual line is the front side of the front body exterior body 1. It becomes the extended region 12.

  Similarly, the rear body exterior body 2 is formed so as to be substantially parallel to the long side 2a that is the side that becomes the waist circumference end, the pair of both sides 2b on which the pair of side seal portions 4 are formed, and the long side 2a. In addition, the shape has a short side 2c that is a side to which the absorbent main body 3 is fixed, and a pair of oblique sides 2d that connect the pair of both sides 2b and the short side 2c. In this case, when one end of the pair of both sides 2b is connected by the long side 2a and the other end of the pair of both sides 2b is connected by an imaginary line, the substantially rectangular region defined is the rear body It becomes the rear main body region 21 of the exterior body 2. On the other hand, when one end of the pair of hypotenuses 2d is connected by the short side 2c and the other end of the pair of hypotenuses 2d is connected by an imaginary line, the substantially trapezoidal region defined is the rear body exterior body 2 It becomes the rear extension region 22.

  Further, as shown in FIG. 2, the rear extension region 22 of the rear body exterior body 2 extends longer in the direction of the crotch region 3 a than the front extension region 12 of the front body exterior body 1. For example, the length in the length direction of the rear extension region 22 is preferably 120% to 250%, or 150% to 200%, where the length of the front extension region 12 is 100%. . For this reason, the area of the rear side extension region 22 of the back body exterior body 2 is larger than the area of the front side extension region 12 of the front body exterior body 1. By setting it as such a shape, the wearer's buttocks can be appropriately covered by the rear side extension region 22 of the back body exterior body 2. On the other hand, with respect to the front body exterior body 1, the inclination of the pair of hypotenuses 1d is gentler than the inclination of the pair of hypotenuses 2d in the rear body exterior body 2, so the front body exterior body 1 and the rear body exterior body 2 are joined. Even if it is a case, the leg periphery opening part 6 will open the front body exterior body 1 side comparatively widely, and it will become easy for a wearer to move both leg parts.

  In the front body exterior body 1 and the back body exterior body 2, a plurality of elastic elastic members are arranged in an extended state. For example, a fluid adhesive such as a hot melt adhesive is directly applied to the elastic elastic member. Thereafter, the elastic stretchable member coated with the adhesive was sandwiched between sheet members such as the inner sheets 15 and 25 located on the skin facing surface side and the outer sheets 16 and 26 located on the skin non-facing surface side. Glued in the state. These elastic elastic members are members for forming gathers around the waist and abdomen of the front body exterior body 1 and the back body exterior body 2. A gather means that a plurality of elastic elastic members sandwiched between the inner sheets 15 and 25 and the outer sheets 16 and 26 contract to cause wrinkles on the inner sheets 15 and 25 and the outer sheets 16 and 26. It is formed. By forming the gathers, the flexibility and adhesion of the front body exterior body 1 and the back body exterior body 2 can be increased.

  As shown in FIG. 2, a plurality of first elastic members 13 and 23 are fixed to the main body regions 11 and 21 of the front body exterior body 1 and the back body exterior body 2, respectively. Reference numeral 13 indicates a first elastic member (front first elastic member) disposed in the front body region 11 of the front body exterior body 1, and reference numeral 23 is disposed in the rear body region 21 of the rear body exterior body 2. The 1st elastic member (rear side 1st elastic member) is shown.

  A plurality of second elastic members 14 and 24 are fixed to the extension regions 12 and 22 of the front body exterior body 1 and the back body exterior body 2, respectively. Reference numeral 14 denotes a second elastic member (front second elastic member) disposed in the front extension region 12 of the front body exterior body 1, and reference numeral 24 denotes a rear extension region 22 in the rear body exterior body 2. The 2nd expansion-contraction member (back side 2nd expansion-contraction member) arrange | positioned is shown.

  As shown in FIG. 2, the first elastic members 13 and 23 and the second elastic members 14 and 24 are arranged in an extended state over the width direction of the front body exterior body 1 and the back body exterior body 2, It is provided at intervals in the length direction. As shown in FIG. 2, the plurality of first elastic members 13 and 23 and the second elastic members 14 and 24 are preferably disposed substantially in parallel. For example, the distance in the length direction of each of the elastic members 13, 14, 23, 24 may be 1 mm to 15 mm, 2 mm to 10 mm, or 3 mm to 5 mm.

  The front side first elastic member 13, the front side second elastic member 14, the rear side first elastic member 23, and the rear side second elastic member 24 are respectively disposed in the main body regions 11 and 21 and the extension region 12. Depending on the area of 22 or the like, a necessary number can be provided as appropriate. For example, it is preferable that the number of the front side first elastic members 13 arranged in the front side main body region 11 is 15 to 30, or 20 to 25. Moreover, it is preferable that the number of the front side 2nd expansion-contraction members 14 arrange | positioned at the front side extension area | region 12 is 1-10, or 3-7. Moreover, it is preferable that the number of the back side 1st expansion-contraction member 23 arrange | positioned at the back side main body area | region 21 is 15-30, or 20-25. Moreover, it is preferable that the number of the back side 2nd expansion-contraction members 24 arrange | positioned at the back side extension area | region 22 is 2-15 or 5-10.

  In addition, as shown in FIG. 2, each elastic stretchable member may be intermittently cut in a region overlapping with the absorbent main body 3 so as not to exhibit stretchability. That is, in the example shown in FIG. 2, among the first elastic members 13 and 23 and the second elastic members 14 and 24, the one that overlaps the absorber 31 of the absorbent main body 3 is intermittently cut in the overlapping region. , It is arranged only on the left and right sides in the width direction.

  Here, in the present invention, thread-like elastic rubber can be suitably used for the first elastic members 13 and 23 and the second elastic members 14 and 24. As such a rubber material, materials such as styrene rubber, olefin rubber, urethane rubber, ester rubber, polyurethane, polyethylene, polystyrene, styrene butadiene, silicone, and polyester can be used. It is particularly preferable to use a thermoplastic elastomer. Examples of the thermoplastic elastomer include styrene elastomers, olefin elastomers, polybutadiene elastomers, polyester elastomers, polyamide elastomers, urethane elastomers, vinyl chloride elastomers, and fluorine elastomers. , Ionomer resins, silicone resins, and the like can be used. These thermoplastic elastomers may be used alone or in combination of two or more.

  Here, in this invention, as the 2nd expansion-contraction members 14 and 24 fixed to the extension area | regions 12 and 22 of the front body exterior body 1 and the back body exterior body 2, it is the elasticity to which an oil agent does not adhere substantially. An elastic member is used. The oil is also called a finishing oil. In order to prevent the elastic elastic member from being entangled with the finishing oil, a predetermined amount adheres to a general elastic elastic member. In the present invention, the second elastic members 14 and 24 that do not have an oil agent attached are used.

  That is, when the elastic elastic member is fixed to the sheet member, the elastic elastic member is first extended to a predetermined elongation rate, and then an adhesive such as a hot melt adhesive is directly applied to the elastic elastic member. Thereafter, the elastic stretchable member coated with the adhesive is bonded to the sheet member. At this time, it was found that if an oil agent adheres to the surface of the elastic elastic member, the oil agent repels the hot melt adhesive, and the hot melt adhesive does not remain sufficiently on the surface of the elastic elastic member. As described above, when the hot melt adhesive hardly adheres to the elastic stretchable member, the bonding force between the elastic stretchable member and the sheet member decreases. In particular, in the extension regions 12 and 22 of the front body exterior body 1 and the back body exterior body 2, the side seal portions 4 do not exist at the left and right ends in the width direction. For this reason, especially the 2nd expansion-contraction members 14 and 24 arrange | positioned in these extension area | regions 12 and 22 have weak joint force with a sheet | seat member. Therefore, at the manufacturing stage of the disposable diaper or when the disposable diaper is mounted, the joint between the second elastic members 14, 24 and the sheet member is peeled off, and the contraction force of the second elastic members 14, 24 is appropriately applied to the sheet member. There was a problem of not being transmitted. Therefore, for the second elastic members 14 and 24 that are easily removed from the sheet member, an elastic elastic member to which no oil is attached is used, and many hot melt adhesives are applied to the surfaces of the second elastic members 14 and 24. To increase the bonding force between the second elastic members 14 and 24 and the sheet member.

  The oil is a liquid oil. Examples of oils are silicone oil, mineral oil, magnesium stearate, and mixed oils thereof. Examples of the components of the oil agent 7 include liquid paraffin, silicone oil, animal and vegetable oils (olive oil, jojoba oil, safflower oil, squalane and squalene, etc.), mono, di, triglyceride, aliphatic ether (myristyl-1,3-dimethylbutyl ether). , Palmityl-1,3-dimethylbityl ether, stearyl-1,3-dimethylbutyl ether, palmityl-1,3-methylpropyl ether and stearyl-1,3-methylpropyl ether), isostearyl-cholesterol ester, etc. Can be mentioned. Examples of the method for applying the oil include coating methods such as slot coating, die coating, bead coating, spiral coating, and gravure coating. In the present invention, the oil agent is not attached to the second elastic members 14 and 24.

  Here, the “elastic elastic member substantially free of an oil agent” used as the second elastic members 14 and 24 means, for example, an elastic elastic member having an oil agent adhesion amount of 0.1 wt% or less. . The oil agent adhesion amount is preferably 0.1% by weight or less, more preferably 0.01% by weight or less, and particularly preferably 0.001% by weight or less. The elastic elastic member used as the second elastic members 14 and 24 has an oil agent adhesion amount of 0.000 wt% to 0.100 wt%, 0.001 wt% to 0.050 wt%, or 0.005 wt%. ~ 0.010% by weight. In view of the gist of the present invention, the second elastic members 14 and 24 are preferably manufactured without going through the step of attaching the oil agent. That is, it is preferable to use elastic elastic members that are not positively attached with an oil agent for the second elastic members 14 and 24. The “step of attaching an oil agent” herein includes both a step of internally adding the oil agent to the elastic elastic member and a step of externally adding the oil agent to the elastic elastic member. For this reason, it is preferable that the 2nd expansion-contraction members 14 and 24 are not what attached the oil agent, whether it is internal addition or external addition. In this case, the oil agent adhesion amount of the second elastic members 14, 24 becomes zero. However, an extremely small amount of oil agent of 0.01% by weight or less may be attached to the elastic elastic members 14, 24.

For example, when the process of attaching an oil agent to the elastic elastic members 14 and 24 is performed, the amount of oil agent attached can be measured by the following procedure. That is, the amount of the oil agent attached is 5 g each for the sample (elastic elastic member) to which the oil agent is attached and the sample (elastic elastic member) to which the oil agent is not attached. Extract with an extractor for 2 hours, air dry for 40 minutes, then dry in a hot air dryer at 105 ° C for 90 minutes, cool in a desiccator for 30 minutes, measure the weight, and obtain from the following formula.

  On the other hand, as the first elastic members 13 and 23 fixed to the main body regions 11 and 21 of the front body exterior body 1 and the rear body exterior body 2, elastic elastic members to which an oil agent is attached may be used. Moreover, as the 1st expansion-contraction members 13 and 23, like the 2nd expansion-contraction members 14 and 24, you may use the elastic expansion-contraction member to which an oil agent does not adhere substantially. In the present invention, in order to improve the workability of the elastic elastic member in the manufacturing process of the disposable diaper, it is preferable to use an elastic elastic member to which an oil agent is attached as the first elastic members 13 and 23. It is preferable that the oil agent adhesion amount of the 1st expansion-contraction members 13 and 23 is 0.1 to 20 weight%, 1 to 15 weight%, or 5 to 10 weight%, for example.

  In the present invention, when the first elastic members 13 and 23 and the second elastic members 14 and 24 are compared, the second elastic members 14 and 24 are thicker than the first elastic members 13 and 23. Is preferred. For example, the second elastic members 14 and 24 preferably have a fineness of 620 dtex or more, and in this case, the first elastic members 13 and 23 preferably have a fineness of 470 dtex or less. For example, the fineness of the second elastic members 14 and 24 is preferably 110% to 200% or 120% to 150% of the fineness of the first elastic members 13 and 23. As described above, by increasing the fineness of the second stretchable members 14 and 24 to which the oil agent is not attached, the surface area to which the hot melt adhesive is attached can be increased. Thereby, the adhesive strength between the second elastic members 14 and 24 and the adhesive is further improved.

  Further, in the present invention, when the first elastic members 13 and 23 and the second elastic members 14 and 24 are compared, the elongation ratio (draft) when the second elastic members 14 and 24 are fixed to the extension regions 12 and 22 is determined. The rate) is preferably lower than the elongation rate (draft rate) when the first elastic members 13 and 23 are fixed to the main body regions 11 and 21. For example, it is preferable that the elongation rate of the first elastic members 13 and 23 is 250% to 500%, 300% to 400%, or 330% to 350%. On the other hand, it is preferable that the expansion rate of the second elastic members 14 and 24 is 200% to 450%, 250% to 350%, or 280% to 300%. For example, the elongation rate of the second elastic members 14 and 24 is preferably 50% to 90% and 70% to 85% with respect to the elongation rate of the first elastic members 13 and 23. The elongation rate is a ratio between the length when the elastic elastic member is in a contracted state and the length when the elastic elastic member is in an extended state. That is, the elongation rate when a 10 cm elastic elastic member is expanded to 20 cm is 200%. Thus, by setting the elongation rate of the second elastic members 14 and 24 to be relatively low, the bonding strength between the second elastic members 14 and 24 and the sheet member becomes relatively high. This prevents the second elastic members 14 and 24 from coming off.

In the present invention, for the second stretchable members 14 and 24 arranged in the extension regions 12 and 22, an elastic stretchable member that has undergone a degreasing step is used before the step of applying a hot melt adhesive or the like. It is good. In the case of degreasing the elastic stretchable member, an oil agent may be attached to the elastic stretchable member before the degreasing step, or the oil agent may not be attached. Preferably, the elastic elastic member manufactured without adhering the oil agent is degreased, and then hot melt adhesive is applied and sandwiched and fixed between the sheet members. Thus, the adhesive force of the 2nd elastic members 14 and 24 and a hot-melt-adhesive improves by using the elastic elastic member which passed through the degreasing process as the 2nd elastic members 14 and 24. FIG. The degreasing step is a surface treatment that removes oil on the surface of the elastic elastic member before applying an adhesive to the surface of the elastic elastic member. As the degreasing step, for example, a step of impregnating the elastic elastic member with an organic solvent (liquid) may be performed. Examples of organic solvents include aromatic hydrocarbons such as toluene, xylene, ethylbenzene, and trimethylbenzene; aliphatic hydrocarbons such as n-pentane, n-hexane, and n-heptane; alicyclics such as cyclopentane and cyclohexane Hydrocarbons; halogenated hydrocarbons such as chlorobenzene, dichlorobenzene, and trichlorobenzene; ether compounds such as anisole; methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, and cyclohexanone.

  In the present invention, a hot melt adhesive is applied to the second elastic members 14 and 24 and fixed to the extension regions 12 and 22 of the front body exterior body 1 and the rear body exterior body 2, and then the extension regions It is preferable to press 12 and 22 with a press roll or the like. Thus, by applying pressure to the extension regions 12 and 22, the coupling force between the second elastic members 14 and 24 and the sheet member that holds the second elastic members 14 and 24 is improved, and the second elastic members 14 and 24 are prevented from coming off. become able to.

  Furthermore, in the present invention, the second elastic members 14 and 24 arranged in the extending regions 12 and 22 are elastic elastic members that have been subjected to a crushing process with a roller or the like before the process of applying a hot melt adhesive or the like. It is good also as using. In this way, by introducing an elastic elastic member such as rubber thread between a pair of pressure rolls and crushing, the fibers constituting the elastic elastic member can be unwound. For this reason, by applying a fluid adhesive such as a hot melt adhesive after pressing the elastic expansion / contraction member, the amount of the adhesive adhering to the elastic expansion / contraction member increases, and the expansion / contraction member and the adhesive Adhesive strength is improved. By using such an elastic expansion / contraction member as the second expansion / contraction members 14, 24, the bonding force between the second expansion / contraction members 14, 24 and the sheet member is further improved, and the second expansion / contraction members 14, 24 are prevented from coming off. The Moreover, when pressurizing the 2nd expansion-contraction members 14 and 24, it is also preferable to heat simultaneously. In this case, a known heat and pressure roller may be used. By pressurizing and heating the second elastic members 14 and 24, the constituent fibers of the second elastic members 14 and 24 are somewhat melted, and the bonding force with the hot melt adhesive applied thereafter is improved.

In addition, the absorptive main body 3 can adopt a known configuration.
The absorbent main body 3 is held in a state of being bridged between the front body exterior body 1 and the back body exterior body 2, and is located in the crotch portion of the wearer when the disposable diaper 100 is worn. Absorb and retain liquid such as urine. The absorbent main body 3 is disposed over the front body 1 and the back body 2 with the crotch part 3 of the disposable diaper as the center. As shown in FIG. 2, the absorbent main body 3 only needs to include an absorber 31, a top sheet 32, and a back sheet 33.

  The absorber 31 is a member for absorbing liquid such as urine and holding the absorbed liquid. The absorber 31 is disposed between a liquid-permeable top sheet 32 and a liquid-impermeable back sheet 33. The absorber 31 has a function of absorbing the liquid that has passed through the top sheet 32 and is made of an absorbent material. As the absorbent material constituting the absorber 31, a known material can be adopted. As the absorbent material, for example, flap pulp, superabsorbent polymer, or hydrophilic sheet may be used. In addition, as the absorbent material, one kind of flap pulp, superabsorbent polymer, or hydrophilic sheet may be used alone, or two or more kinds may be used in combination. The absorbent material is usually formed and used in a single-layer or multi-layer mat shape. The shape of the absorber 31 can be appropriately designed according to the shape, size, and application of the disposable diaper. For example, the shape of the absorber 31 may be an hourglass shape as shown in FIG. Moreover, it is good also as a rectangular type, an elliptical type, or a gourd type currently used for the general disposable diaper.

  The top sheet 32 is a member that is in direct contact with the skin of the wearer's crotch and allows liquid such as urine to pass through the absorber 31. For this reason, the top sheet 32 is made of a liquid-permeable material having high flexibility. Further, the top sheet 32 is disposed so as to cover the skin contact surface side of the absorber 31. The example of the impermeable material which comprises the top sheet 32 is a woven fabric, a nonwoven fabric, or a porous film. Further, for example, a fiber made of a thermoplastic resin such as polypropylene, polyethylene, polyester, or nylon, which has been subjected to a hydrophilization treatment and further made into a non-woven fabric may be used.

  The back sheet 33 is a member for preventing the liquid that has passed through the top sheet 32 and absorbed by the absorber 31 from leaking to the outside of the diaper. For this reason, the back sheet 33 is made of a liquid-impermeable material. The back sheet 33 covers the absorbent body 31 from the non-skin contact surface side in order to prevent liquid leakage from the bottom surface of the absorbent body 31. An example of the impermeable material constituting the back sheet 33 is a liquid impermeable film made of polyethylene resin. In particular, it is preferable to use a microporous polyethylene film in which a plurality of fine pores of 0.1 to 4 μm are formed.

Next, examples of disposable diapers according to the present invention will be described.
In this embodiment, “Product Name: Roika (registered trademark)” and “Product Code: Polyurethane” manufactured by Asahi Kasei Fibers Co., Ltd. are used as the first elastic members fixed to the main body region of the front body exterior body and the back body exterior body. Fiber (general name spandex) "(hereinafter," thread rubber A ") was used. The oil agent adhesion amount of the thread rubber A was 3% by weight (average value) for the oil agent (mineral oil) and 2% by weight (average value) for the oil agent (others). Further, the fineness of the rubber thread A was 470 dtex. The elongation rate of the rubber thread A was 330%.

  In this example, “product name: Lycra (registered trademark) fiber polyurethane fiber” manufactured by Toray Operontex Co., Ltd. is used as the second stretchable member fixed to the extension region of the front body exterior body and the back body exterior body. (Hereinafter referred to as “thread rubber B”). The amount of oil agent attached to the thread rubber B was 0% (impossible to be measured). The rubber thread B was manufactured without going through a step of attaching an oil agent (internal addition / external addition) to the elastic elastic member. Further, the fineness of the rubber thread B was 620 dtex. The elongation rate of the rubber thread B was 280%.

  Disposable diapers were manufactured by placing the rubber thread A in the main body region of the front body exterior body and the back body exterior body and the rubber thread B in the extension region. A hot melt adhesive was used for bonding the thread rubber A and the thread rubber B. The hot melt adhesive used was manufactured by Sekisui Fuller. In addition, disposable diapers were manufactured according to a general manufacturing method.

  When the disposable diaper was manufactured using the thread rubber A and the thread rubber B as described above, the thread rubber A and the thread rubber B were in a good joined state with the sheet member that holds them. In particular, the rubber thread B arranged in the extension region is joined to the sheet member from end to end, and there are hardly any places that are missing from the sheet member. Further, even if the operation of gripping and extending the extension region where the rubber thread B was arranged by hand was repeatedly performed, there were hardly any places where the rubber thread was peeled off from the sheet member. As described above, by adopting the thread rubber B to which the oil agent is not attached as the elastic expansion and contraction member arranged in the extension region, a clear improvement was observed in the joining state.

Comparative example

Then, the comparative example of a disposable diaper is demonstrated.
In the comparative example, the thread rubber A (oil agent adhered to both the first elastic member fixed to the main body region of the front body exterior body and the back body exterior body and the second elastic member fixed to the extension region. Used). Regarding other conditions, the example and the comparative example were the same.

  When the disposable diaper was manufactured under the above conditions, the thread rubber A joined to the main body region was fixed to the extension region although the joining state with the sheet member sandwiching it was good. It was observed that the thread rubber A was partially peeled from the sheet member that sandwiched it. The rubber thread A arranged in the extending region has a significant dissociation from the sheet member, particularly at both end portions in the width direction. In addition, when the extension region where the thread rubber A is arranged is grasped by hand and expanded and contracted repeatedly, particularly when the thread rubber A is pulled, a popping sound is generated and the thread rubber A extends. The appearance of peeling from the sheet member forming the region was observed.

  As described above, when the example and the comparative example are compared, the example in which the rubber thread B to which the oil agent is not attached is used as the elastic stretchable member arranged in the extension region has a bonding state more than expected. It was found that it improved.

  As mentioned above, in this specification, in order to express the content of this invention, embodiment of this invention was described, referring drawings. However, the present invention is not limited to the above-described embodiments, but includes modifications and improvements obvious to those skilled in the art based on the matters described in the present specification.

  The present invention relates to a pants-type disposable diaper for infants and the elderly. Therefore, the present invention can be suitably used in industries related to childcare and nursing care.

1 ... front body exterior body (front body)
2 ... Back body exterior (back body)
DESCRIPTION OF SYMBOLS 3 ... Absorbent main body 3a ... Crotch area 4 ... Side seal part 11, 21 ... Main body area | region 12, 22 ... Extension area | region 13, 23 ... 1st elastic member 14, 24 ... 2nd elastic member

Claims (3)

Having a crotch region located between the front body, the back body, and the front and back bodies;
The front body and the back body are joined at opposite end portions in side seal portions (4) provided at both ends of the disposable diaper in the width direction,
The front body and the back body are
A body region (11, 21) in which the side seal portion (4) is formed at both end portions in the width direction;
An extension region (12, 22) having a shape extending from the main body region (11, 21) toward the crotch region and gradually becoming narrower in width toward the crotch region. Have
In the main body region (11, 21), one or a plurality of first elastic members (13, 23) are arranged in an extended state along the width direction,
In the extended region (12, 22), one or a plurality of second elastic members (14, 24) are arranged in an extended state along the width direction.
A method for manufacturing a pants-type disposable diaper,
A degreasing step of degreasing the second elastic member (14, 24);
After the degreasing step, an adhesive is applied to the second elastic member (14, 24), and the second elastic member (14, 24) is joined to the region corresponding to the extension region (12, 22). It includes a bonding step for, a,
Said 1st expansion-contraction member (13,23) is a manufacturing method of the disposable diaper whose oil agent adhesion amount is 5 weight% or more . The manufacturing method according to claim 1, wherein the degreasing step is a step of setting an oil agent adhesion amount of the second elastic member (14, 24) to 0.1 wt% or less. The manufacturing method according to claim 2, wherein the degreasing step is a step of degreasing the second elastic member (14, 24) to which an oil agent has been previously attached.

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