Abstract:
A disposable pull-on garment has an elasticized waist-opening and a pair of elasticized leg-openings. At least one of the inner or outer surfaces of a peripheral edge of the waist opening includes a slippage resistant sheet. The sheet has a high friction coefficient so that the peripheral edge of the waist opening is easily and reliably gripped when the garment is pulled on by a wearer.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to a disposable pants-type garment. 
     In the disposable pull-on garment such as a disposable pull-on diaper, a sheet, for example, of a nonwoven fabric having a relatively low friction has conventionally been used as a topsheet so that the wearer&#39;s skin may experience a comfortable touch. Japanese Patent Application Disclosure No. 1999-104180 describes a pull-on diaper provided on the outer surface of its backsheet with a plurality of window-like recesses adapted to be engaged with the finger tips as the diaper is pulled upward along the wearer&#39;s torso with a peripheral edge of a waist-opening held with the finger tips after the wearer&#39;s legs have been put through the diaper. The window-like recesses function to prevent the finger tips from slipping off from the peripheral edge of the waist-opening. 
     In the case of such a pull-on diaper of prior art, it is considerably difficult or troublesome for both the baby and the aged to localize the window-like recesses and then to insert his or her finger tips into them if the diaper must be put on his or her body by his or her own hands. 
     SUMMARY OF THE INVENTION 
     It is an object of this invention to provide a disposable pull-on garment improved so that the peripheral edge of the waist-opening may be easily and reliably held with the wearer&#39;s own finger tips. 
     There is provided a disposable pull-on garment having an elasticized waist-opening and a pair of elasticized leg-openings. The garment further comprises a front waist region, a rear waist region, and a crotch region. The front and rear regions are joined along transversely opposite side edges thereof to form a the waist-opening and a the pair of leg-openings. Respective peripheral edges of the waist-opening and a pair of leg-openings are elastic. Each of the front and rear regions have inner and outer surfaces which include inner and outer peripheral edge surfaces of the waist opening and inner and outer surfaces of remaining zones. At least one of the inner and outer peripheral edge surfaces of the waist-opening is provided with a slippage-resistant sheet having a friction coefficient higher than a friction coefficient of the inner surfaces of the remaining zones. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view showing a partially cutaway disposable pull-on diaper exploited in accordance with this invention as partially broken away; 
     FIG. 2 is a perspective view showing the partially cutaway diaper in its developed state; 
     FIG. 3 is a sectional view taken along line III—III in FIG. 2; 
     FIG. 4 is a view similar to FIG. 2 but showing another embodiment of this invention; 
     FIG. 5 is a sectional view taken along line V—V in FIG. 4; and 
     FIG. 6 is a view similar to FIG. 1 but showing still another embodiment of this invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Details of this invention will be more fully understood from the description of a disposable pull-on diaper as one embodiment as will be given hereunder with reference to the accompanying drawings. 
     A pull-on diaper  1  shown by FIG. 1 in a perspective view partially broken away comprises a liquid-pervious topsheet  2 , a liquid-impervious backsheet  3  and an absorbent core  4  disposed between these two sheets  2 ,  3 . Configurationally, the diaper  1  is composed of a front waist region  6 , a rear waist region  7  and a crotch region  8  extending between these two waist regions  6 ,  7 . The front and rear waist regions  6 ,  7  respectively have their transversely opposite side edges put flat and joined together at spots  9  arranged intermittently along the respective side edges in vertical direction to form a waist-opening  11  and a pair of leg-openings  12 . Portions of the topsheet  2  and the backsheet  3  extending outward beyond a peripheral edge of the absorbent core  4  are joined to each other. In the vicinity of the waist-opening  11  and the leg-openings  12 , elastic members  13  associated with the waist-opening  11  and elastic members  14  associated with the leg-openings  12  circumferentially extend between the topsheet  2  and the backsheet  3  and are secured under tension to the inner surface of at least one of these sheets  2 ,  3 . 
     FIG. 2 is a perspective view partially broken away, showing the diaper  1  of FIG. 1 as the front and rear waist regions  6 ,  7  are separated from each other along the respective arrays of the spots  9  and developed in a direction indicated by a double-headed arrow A—A. Along an upper end  16  of the front waist region  6  which defines the waist-opening  11 , a slippage-resistant sheet  21  having its surface of a relatively high friction coefficient is attached on the upper surface of the topsheet  2 . This slippage-resistant sheet  21  has a width W as measured longitudinally of the diaper  1  (i.e., vertically of FIG. 1) and a length L as measured circumferentially of the trunk regions. The slippage-resistant sheet  21  has a friction coefficient higher than that of the topsheet  2  and more specifically has a static friction coefficient of 0.8 or higher and a dynamic friction coefficient of 0.035 or higher both measured by a measuring apparatus KES-G5 of KATO TECH Co., Ltd. (Kyoto City, Kyoto Prefecture, Japan). The width W of the slippage-resistant sheet  21  extends downward from the waist-opening&#39;s peripheral edge of the diaper  1  preferably beyond the elastic member  13  associated with the waist-opening  11 . An upper limit of the width W is 60 mm. The length L is at least 20 mm and preferably extends over an entire width of the front waist region  6  as shown. It is undesirable to form the upper end  16  of the disposable diaper  1  only by the slippage-resistant sheet  21  since this would complicate making the diaper. The slippage-resistant sheet  21  as illustrated may be replaced by a plurality of relatively short slippage-resistant sheets  21  arranged intermittently in the circumferential direction. 
     FIG. 3 is a sectional view taken along line III—III in FIG.  2 . Along the upper end  16  of the front waist region  6 , the topsheet  2  and the backsheet  3  are joined together by means of hot melt adhesive  22 . The slippage-resistant sheet  21  is attached in the vicinity of its upper zone  23  (left-hand zone as viewed in FIG. 3) as well as its lower zone  24  (right-hand zone as viewed in FIG. 3) to the upper surface of the topsheet  2  by means of hot melt adhesive  22 . An intermediate zone  26  of the slippage-resistant sheet  21  defined between the upper and lower zones  23 ,  24  may be either attached or not attached to the topsheet  2 , the latter case is illustrated in FIG.  3 . The adhesive  22  is applied on the slippage-resistant sheet  21  so as to leave the respective outermost edges of the upper and lower zones  23 ,  24  free and therefore there is no possibility that the adhesive  22  might come in contact with the wearer&#39;s skin. The slippage-resistant sheet  21  may be formed by various materials, for example, a nonwoven fabric made of elastic fiber based on rubber such as urethane rubber, a nonwoven fabric made of the elastic fiber of 30˜100% by weight and inelastic synthetic fiber of 70˜0% by weight, a sheet based on rubber such as urethane rubber and a foamed sheet made of foamed urethane or the like. The foamed sheet is preferably of open cell type to improve a breathability of the diaper  1 . 
     The diaper  1  constructed as has been described above can be easily put on by pulling the diaper  1  upward with the upper end  16  of the front waist region  6  held with the finger tips without the finger slipping off from the upper end  16 . The slippage-resistant sheet  21  having its intermediate zone  26  not attached to the topsheet  2  as in the case of the embodiment shown by FIG. 3 is particularly advantageous since the intermediate zone  26  is relatively movable together with the wearer&#39;s finger tips and effective to improves a slippage-resistant effect. Additionally, the effect of the slippage-resistant sheet  21  can be improved by adjusting a friction coefficient presented by respective peripheral edges  27  (See FIGS. 1 and 2) of the leg-openings  12  on their inner surfaces to be lower than the friction coefficient presented by the slippage-resistant sheet  21 . For example, a static friction coefficient of the former may be adjusted to be ⅓ or less of the static friction coefficient of the latter and a dynamic friction coefficient of the former may be adjusted to be ½ or less of the dynamic coefficient of the latter to improve the effect of the slippage-resistant sheet  21  correspondingly. In this case, the inner surfaces of said peripheral edges  27  may be defined by a spun lace nonwoven fabric or a spun bond nonwoven fabric made of conjugated fiber comprising polypropyrene as a core and polyethylene as a sheath wherein said conjugated fiber may be in crimped state or not. It is also possible to reduce the friction coefficient of the inner surfaces of the peripheral edges  27  by appropriately surface-treating them. 
     FIG. 4 is a view similar to FIG. 2 but showing another embodiment of this invention. According to this embodiment of the diaper  1 , the inner surfaces of the upper ends  16 ,  17  of the front and rear waist regions  6 ,  7 , respectively, are formed by a front slippage-resistant sheet  21 A and a rear slippage-resistant sheet  21 B both made of foamed urethane, respectively. The front slippage-resistant sheet  21 A is formed with a plurality of through-holes  31  arranged intermittently in the circumferential direction. 
     FIG. 5 is a sectional view taken along line A—A in FIG.  4 . The through-hole  31  of the front slippage-resistant sheet  21 A has a diameter of at least 5 mm and extends through the sheet  21 A in the direction of its thickness. 
     As will be apparent from FIGS. 4 and 5, this diaper  1  may be provided with the slippage-resistant sheets  21  ( 21 A,  21 B) in both the front and rear waist regions  6 ,  7 . The through-holes  31  as those of the front slippage-resistant sheet  21 A are effective to prevent the finger tips once engaged with these through-holes  31  as the diaper  1  is held with the finger tips from slipping off from the diaper  1 . 
     FIG. 6 is a view similar to FIG. 1 but showing still another embodiment of this invention. According to this embodiment, the outer surface of the front waist region  6  is provided along the upper end  16  defining the waist-opening  11  with a pair of the slippage sheets  21  spaced from each other in the circumferential direction. In this case, these slippage sheets  21  have a static friction coefficient and/or a dynamic friction coefficient higher than those presented by the inner surface of the zone other than said longitudinal end  16 . In such diaper  1 , it is also possible to attach an additional slippage-resistant sheet  21  to the inner surface of the front waist region  6  along its upper end  16 . It is also possible to attach the slippage-resistant sheets  21  to the outer surface and/or the inner surface of the rear waist region  7  along its upper end  17  in addition to or in the place of those attached to the front waist region  6 . The slippage-resistant sheets  21  arranged intermittently in the circumferential direction are not limited to one pair as in the embodiment shown in FIG. 6 but it is also possible to provide a single slippage-resistant sheet  21  or three or more slippage-resistant sheets  21  in the circumferential direction. 
     To exploit this invention, the stock materials conventionally used in the relevant art may be used to form the topsheet  2  and the backsheet  3  and the absorbent core  4 , respectively. This invention is applicable not only to the diaper  1  as shown and described, but also to disposable pants, disposable training pants or the like.