Abstract:
A disposable hygiene article ( 2 ), such as an incontinence diaper or incontinence pad has a composite non-woven fabric ( 38 ) that is provided with at least one cuff element ( 16 ) and a non-woven fabric or film component ( 10, 12 ). The cuff element ( 14 ) is attached to the non-woven fabric or film component ( 10, 12 ) in at least some areas by means of a joining pattern ( 36 ) encompassing discrete ultrasonic welding points ( 30 ) in order to form the composite non-woven fabric ( 38 ). At least some sections of the joining pattern ( 36 ) are curved. The joining pattern has a maximum index (I) of variation of the ultrasonic welding points of 40 percent. An area seized by the welding points has a density within the joining pattern which decreases in rear and front end portions along endwards directed and inwardly curved extensions of the joining pattern.

Description:
[0001]    This application a continuation of Ser. No. 12/310,847 filed Mar. 10, 2009 as the national stage of PCT/EP2007/008134 filed on Sep. 19, 2007 and also claims Paris Convention priority of DE 10 2006 046 420.6 filed Sep. 22, 2006, the entire disclosures of which are hereby incorporated by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The invention relates to a disposable hygiene article or surgical covering item, or surgical garment for single use, such as an incontinence diaper, incontinence pad, surgical drape, or surgical coat, comprising a composite nonwoven fabric, that is provided with at least one nonwoven fabric component and another nonwoven fabric or film component. The first nonwoven fabric component is attached to the other nonwoven fabric or film component in at least some areas by means of a joining pattern encompassing discrete ultrasonic welding points in order to form the composite nonwoven fabric. The joining pattern extends in a longitudinal direction and a transverse direction that runs perpendicular thereto, the distance in the longitudinal direction being longer than the distance in the transverse direction. At least some sections of the joining pattern are curved. 
         [0003]    For example, on hygiene articles, in particular, incontinence products, such as incontinence diapers, lateral barriers standing toward the user during use, called cuff elements, are provided that comprise a nonwoven fabric component and are attached in the longitudinal direction of the product to another nonwoven fabric or film component of the hygiene article by means of ultrasonic welding or bonding. In the field of the hygiene articles addressed here, the joining of nonwoven fabric and/or film components by means of ultrasonic welding devices is generally known. For example, a joining pattern comprising discrete ultrasonic welding points can be implemented in a continuous, that is, never-ending production machine for nonwoven articles of the type stated above by using a contour roller rolling in the machine direction and an anvil made to vibrate in the ultrasonic range, which is termed a sonotrode. The contour roller and sonotrode form a gap between them through which the weldable components to be joined are fed during the continuous production process. The nonwoven fabric or film components are then welded by transfer of the vibration energy on the raised areas of the contour roller. The strength of the weld can be adjusted by varying the distance between the sonotrode and the contour roller and by controlling the vibration of the sonotrode. 
         [0004]    The applicant has ascertained that, in particular, on fast-operating production machines, it is extremely difficult to achieve a uniformly secure weld without damaging the components if the area of the weld varies greatly in the machine direction, because this necessitates very frequent variation in control of the welding device or its sonotrode. It is extremely difficult to almost impossible to achieve a stable operating condition. If, on the other hand, the area of a joining pattern varies little or not at all in the machine direction, for example, if it does not vary in the circumferential direction of the contour roller and, for example, comprises concentric embossing lines or embossing points on the contour roller, the problem described above does not occur because the welded area does not change so rapidly in the machine direction. If, on the other hand, the joining pattern is oblique with respect to the machine direction or comprises oblique sections, the proportion of the welded area in the machine direction will vary greatly and the problems described above will occur. If, for example, on one product, the joining pattern comprises arc-shaped areas with tight curvature with respect to the machine direction, achieving process reliability in the welding of nonwoven fabric components poses a problem. If this problem is not solved, unwelded points or damage to the nonwoven fabric or film components due to overwelding will occur. In either case, correct functioning of the article being produced is jeopardized. Extremely short control cycles in operating the ultrasonic welding device can also result in the device overshooting and frequently causing direct contact between the contour roller and the sonotrode. This results in damage to the device, considerably reducing its service life. The sonotrode and contour roller then require frequent replacement due to the high wear caused by direct contact between the two machine components. 
         [0005]    The object of this invention is to provide a hygiene article or a surgical covering item or surgical garment of the type described above with which the problems described above do not occur, while nevertheless permitting production of a joining pattern of discrete ultrasonic welding points that varies in the machine direction. For example, it must be possible to fix a standing cuff element according to a joining pattern that oscillates in the form of arcs with respect to the machine direction or generally to join weldable nonwoven fabric or film components of the article stated above fed in as flat material without being limited to a joint that is precisely straight in the machine direction. In particular, damage to components being welded together during the welding process and partially deficient welding of the components must be precluded. Similarly, damage to the ultrasonic welding device must be avoided and a long service life ensured in conjunction with fast-operating production machines. 
       SUMMARY OF THE INVENTION 
       [0006]    This object is inventively achieved with a hygiene article, incontinence diaper or incontinence pad, the article having a longitudinal direction and a transverse direction perpendicular to the longitudinal direction as well as a central axis extending in the longitudinal direction. The inventive article comprises a nonwoven fabric or film component and at least one cuff element on a left and right side of the hygiene article forming a left and right upstanding leakage barrier and extending substantially in the longitudinal direction of the article. Discrete ultrasonic welding points are disposed in a joining pattern to attach the cuff element to the nonwoven fabric or film component. An extension of the joining pattern in the longitudinal direction exceeds an extension of the joining pattern in the transverse direction, the joining pattern having a central portion travelling substantially in the longitudinal direction of the article as well as rear and front end portions. The rear and front end portions of the joining pattern curve inwardly towards the central axis of the article along an endwards directed extension of the joining pattern. An index of variation of the joining pattern is no more than 40% and an area seized by the ultrasonic welding points in the joining pattern has a density within the joining pattern which decreases in the rear and front end portions along the endwards directed and inwardly curved extension of the joining pattern. The solution to the object of the invention is therefore to design the joining pattern of the ultrasonic welding points in such a way that the area seized by the welding in the machine direction does not vary so much that the problems described above occur. For example, this can be achieved by variation and appropriate disposition of the number of ultrasonic welding points per unit area, that is, e.g. by selecting the distance between the ultrasonic welding points and/or by varying the respective area of the ultrasonic welding points. 
         [0007]    The index of variation of the ultrasonic welding points is calculated as follows: The article in accordance with the invention is considered divided into 5-mm wide longitudinal sections in the first direction. These longitudinal sections therefore extend over 5 mm in the longitudinal direction, which is also the machine direction, and perpendicular thereto in the transverse direction, which is the transverse direction on the product. Each of these sections extending 5 mm in the longitudinal direction encompasses a number of ultrasonic welding points, each of which constitutes a welded proportion of the area. It is possible to calculate the welded area A i  of each 5-mm section (sum of the areas of the individual ultrasonic welding points in a 5-mm section). It is also possible to calculate a mean value Ā of the area A i  seized by the ultrasonic welding points of each section. For example, it is possible to divide an 820-mm long article into 164 such 5-mm sections in the longitudinal direction. For each section, it is possible to calculate the welded area A i  and from these 164 A i  values, it is then possible to calculate the arithmetic mean Ā of the welded area of the 5-mm sections. A value s can be calculated from these according to the following formula: 
         [0000]    
       
         
           
             s 
             = 
             
               
                 
                   1 
                   
                     N 
                     - 
                     1 
                   
                 
                  
                 
                   
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                       = 
                       1 
                     
                     N 
                   
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                       ( 
                       
                         
                           A 
                           i 
                         
                         - 
                         
                           A 
                           _ 
                         
                       
                       ) 
                     
                     2 
                   
                 
               
             
           
         
       
     
         [0008]    Thus the error sum of squares of A i  of the individual 5-mm sections is calculated from the mean value Ā of the welded surfaces of the 5-mm sections and divided by (N−I) and the square root is taken of the result. Based on this, the index I (in %) of variation of the ultrasonic welding points is defined as follows: 
         [0000]    
       
         
           
             I 
             = 
             
               
                 s 
                 
                   A 
                   _ 
                 
               
               × 
               
                 100 
                  
                 
                   [ 
                   % 
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         [0009]    It has been shown that the range of the index of variation of the ultrasonic welding points of no more than 40% is suitable, in particular, for the machine velocities relevant here of 100 m/min to 1000 m/min, in particular, of 150 m/min to 700 m/min, to ensure process reliability of the ultrasonic weld joint between nonwoven fabric components and/or film components of the articles in question here. It has proven especially advantageous if the index of variation of the ultrasonic welding points is no more than 35%, in particular, no more than 30% and further, in particular, no more than 25%. 
         [0010]    This invention proves especially advantageous on an article in which the composite nonwoven fabric comprises on both sides at least one cuff element standing at least in sections, forming a leakage barrier, and essentially extending in the longitudinal direction. As mentioned above, a cuff element is a lateral barrier formed from a flat material that is raised from the substrate mostly due to elastification, in particular, toward the body of the user and thus provides a leakage barrier, chiefly at the sides of the article. In the case of an inventive article, this cuff element is joined to further (chassis) nonwoven fabric or film components of the article by an inventively constituted joining pattern of ultrasonic welding points. 
         [0011]    In particular, if the article according to the claims is a hygiene article for single use, it proves advantageous if the article comprises a topsheet that is permeable at least in some areas, a backsheet that is impermeable at least in some areas, and a storage core that absorbs body fluids and is disposed between the two. In such a case, it can be advantageous for the nonwoven fabric or film component to be the topsheet or the backsheet, so that the cuff element is attached to the topsheet or backsheet by the inventive joining pattern of ultrasonic welding points. 
         [0012]    To join a cuff element to further components of the article by means of ultrasonic welding, it proves advantageous if the joining pattern comprises a first partial joining pattern that, at least in areas, constitutes a cuff base, that is, an area along which the cuff element is attached to the further nonwoven fabric component or film component. When the article is put to its intended use, this then constitutes a fold line along which the cuff element is raised away from a base plane. 
         [0013]    In a further embodiment of this inventive concept, the cuff base constituted in some areas by the first partial joining pattern can additionally be constituted or limited in some areas by a second partial joining pattern that is substantially straight and, in particular, largely extends parallel to the longitudinal direction. Here and hereafter a partial joining pattern is referred to as substantially straight when, over a length of 200 mm in the longitudinal direction, an extension in the transverse direction of no more than 6 mm can be ascertained. 
         [0014]    In yet a further embodiment, the cuff base is constituted at least in sections by the first partial joining pattern, the second partial joining pattern and a third curved partial joining pattern. In the first direction, the second partial joining pattern is disposed preferably between the first and the third partial joining pattern. The result is therefore a cuff base that, in a front area and in a rear area of the article, extends transverse to the longitudinal direction, in particular, curved in the shape of an arc with respect to the longitudinal direction and, in the intermediate area, is substantially straight and, in particular, parallel to the longitudinal direction. Such a configuration proves especially advantageous, particularly for hygiene articles for single use, such as incontinence diapers, incontinence pads. The invention makes it possible to dispose the cuff elements relatively far toward the outside in the transverse direction in a front and rear region of the article and then to have them curve inwardly toward the crotch area. In the crotch area, the cuff elements or the cuff base or cuff base lines then advantageously extend largely parallel and have a smaller distance between them in the transverse direction than in the front and rear areas. With this invention, it becomes possible to establish a stable connection between the cuff element and chassis materials of a hygiene article that meets the desired requirements for configuration of the article and is nevertheless producible with process reliability by complying with the inventive design of the joining pattern. 
         [0015]    In a further embodiment of the invention, it proves advantageous if, in an inventive article, the joining pattern in the longitudinal direction is considered virtually in three sections of equal length, that is, is divisible into a start section, an adjoining center section, and an end section adjoining the center section and the index of variation of the area of the start section and/or of the end sections of the joining pattern is no more than 40%, in particular, no more than 35%, further, in particular, no more than 30%, further, in particular, no more than 25%. According to this further embodiment of the invention, the inventively imposed condition is not only fulfilled over the entire claimed article, considering all 5-mm sections containing ultrasonic welding points, but also for the corresponding 5-mm sections of the start section overlapping by one third and the end section overlapping by one third. 
         [0016]    As already stated, the inventive design of the joining pattern of the ultrasonic welding points can be achieved by various measures. In particular, it can prove advantageous if the distance between the discrete ultrasonic welding points is smaller in a first area than in a second area. 
         [0017]    In particular, it proves useful if the distance between individual (discrete) ultrasonic welding points in a first area is 0.1 to 2.5 mm, in particular, 0.2 to 1.5 mm, and further, in particular, 0.2 to 1.0 mm and, in a second area, is 2 to 20 mm, in particular, 3 to 15 mm, further, in particular, 4 to 10 mm. 
         [0018]    It is also possible for the density per unit area of the ultrasonic welding points (number of points per unit area) to be greater in a first area than in a second area. 
         [0019]    The the first area is a partial area of the joining pattern; it can constitute, in particular, one partial area of the first and/or second and/or third partial joining pattern of the cuff base. 
         [0020]    According to a further embodiment of the invention, the first and/or third partial joining pattern comprises a set of at least two, in particular, at least three curves, further, in particular, at least four, further, in particular, at least five curves. Preferably at least two of the curves of a set should be separated by a small maximum distance of 2 to 20 mm, in particular, 2 to 15 mm and further, in particular, 3 to 10 mm. Furthermore, it proves advantageous if at least two of the curves of a set are separated by a greater maximum distance of 10 to 70 mm, in particular, 15 to 60 mm and further, in particular, 20 to 50 mm. For example, this is possible and advantageous if the set consists of three curves and the maximum distance of the first outer curve from the center curve has the previously stated low value and the maximum distance of the second outer curve from the center curve is a greater distance. Of course, in the case of a set of more than three curves, at least two curves of a set can have a different maximum distance between them. 
         [0021]    Moreover, it proves advantageous if one or more of the curves has a radius of at least 60 mm, in particular, at least 70 mm, further, in particular, 80 mm, further, in particular, at least 90 mm, further, in particular, at least 100 mm and further, in particular, no more than 150 mm. The curves can also have a variable distance between them. 
         [0022]    The curves are advantageously not a weld line that is continuous over its extension but a series of consecutive ultrasonic welding points that is then largely linear and thus forms the curve. By varying the distance between the ultrasonic welding points and/or by changing the distance between the curves it is possible to vary the proportion of the area of the weld points in each 5-mm section, so that, overall, the claimed index range is complied with. 
         [0023]    It proves advantageous if the joining pattern has first discrete ultrasonic welding points with an area of 0.3 to 4 mm 2 , in particular, 0.3 to 3 mm 2 , further, in particular, 0.3 to 2 mm 2 , further, in particular, 0.5 to 1.1 mm 2  and further, in particular, 0.7 to 0.9 mm 2 . 
         [0024]    As already stated, it can be advantageous if the joining pattern encompasses first and second discrete ultrasonic welding points and the area of the first discrete ultrasonic welding points is smaller than that of the second discrete ultrasonic welding points. 
         [0025]    The shape of the area of the ultrasonic welding points is relatively uncritical; they can be circular or oval or triangular or polygonal or sickle-shaped or dot-and-dashed or star-shaped or linear. 
         [0026]    For example, in the production of hygiene articles, it can prove advantageous if the sum (A i ) of the areas of the ultrasonic welding points of a 5-mm long section of the joining pattern in the longitudinal direction is on average 2 to 25 mm 2 , in particular, 3 to 18 mm 2 , in particular, 4 to 12 mm 2  and further, in particular, 6 to 10 mm 2 . In the case of a hygiene article with cuff elements on both sides, these are preferably the values that apply to the joining pattern of one of the cuff elements. 
         [0027]    Furthermore, it proves advantageous if the sum (A i ) of the areas of the ultrasonic welding points of one, in particular, each 5-mm long section of the joining pattern in the longitudinal direction is no more than 30 mm 2 , in particular, no more than 23 mm 2 , further, in particular, no more than 18 mm 2 , further, in particular, no more than 16 mm 2 , further, in particular, no more than 15 mm 2 . 
         [0028]    In the production of an inventive article, it proves advantageous if, in the design of the joining pattern of the ultrasonic welding points, the deviation of the sum (A i ) of the areas of the ultrasonic welding points of each 5-mm long section of the joining pattern in the longitudinal direction from the sum (A i ) of the areas of the ultrasonic welding points of a directly adjacent 5-mm long section of the joining pattern is less than 70%, in particular, less than 60%, in particular, less than 50%, further, in particular, less than 40%. This means that the entire welded area (A i ) of two adjacently disposed 5-mm sections must differ by no more than the above-mentioned ranges. In this case, this deviation of two adjacent 5-mm long sections refers to the sum A i  of the areas of the ultrasonic welding points of the section whose sum A i  of the areas of the ultrasonic welding points has the higher value. 
         [0029]    Furthermore, it proves advantageous with respect to consistent product quality if the deviation of the sum of the areas of the ultrasonic welding points of at least 50%, in particular, of at least 60%, further, in particular, of at least 70% and further, in particular, of at least 80%, and, very especially, of at least 90% of the 5-mm long sections of the joining pattern from the sum (A i ) of the areas of the ultrasonic welding points of a directly adjacent 5-mm long section of the joining pattern is less than 40%, in particular, less than 30%, in particular, less than 25%. 
         [0030]    The invention also relates to a method for the production of a hygiene article or surgical covering item, or surgical garment of the inventive type with the characteristics claimed. 
         [0031]    Furthermore, it proves advantageous if the claimed article is constituted such that the joining pattern extends 300 to 2000 mm, in particular, 350 to 1500 mm, in particular, 400 to 1200 mm, further, in particular, 450 to 1100 mm and further, in particular, 500 to 1000 mm in a longitudinal direction and running perpendicular thereto preferably 10 to 1200 mm, in particular, 15 to 1000 mm, in particular, 20 to 500 mm, further, in particular, 30 to 200 mm and further, in particular, 40 to 150 mm and further, in particular, 50 to 130 mm in a transverse direction. 
         [0032]    Further characteristics, details, and advantages of the invention can be seen from the appended patent claims and from the drawings and the following description of the invention using explanatory examples. The drawings show: 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         [0033]      FIG. 1  a top view of a hygiene article in the form of an incontinence diaper in the unfolded condition; 
           [0034]      FIG. 2  a sectional view with intersection plane II-II in  FIG. 3 ; 
           [0035]      FIGS. 3 ,  4  a partially perspective view of an ultrasonic welding device for production of inventive articles in a continuous production process using continuously fed flat material; 
           [0036]      FIG. 5  an enlarged detailed view of a joining pattern from  FIGS. 5 ,  6  (viewed as a top view according to the Arrow V onto the device according to  FIG. 4 ; 
           [0037]      FIG. 6  a top view of an inventively constituted joining pattern to illustrate the conceptual division into 5-mm sections; 
           [0038]      FIG. 7  a diagram in which the area proportion of the ultrasonic welding points of each 5-mm section is entered and the underlying joining pattern is indicated (not comprised in the scope of protection of the invention); and 
           [0039]      FIG. 8  a corresponding diagram with an inventively constituted joining pattern structure. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0040]      FIG. 1  shows a hygiene article numbered in its entirety with the reference symbol  2  in the form of an incontinence diaper for single use.  FIG. 2  depicts a schematic sectional view with intersection plane II-II in  FIG. 1 . Hygiene article  2  comprises a topsheet  4  and an impermeable backsheet  6  and an interposed absorption body  8 . The topsheet  4  is a permeable nonwoven fabric component, in particular, a card or spunbonded nonwoven, preferably with a mass per unit area of 8-30 g/m 2 , in particular, 12 to 25 g/m 2 , in particular, 14 to 22 g/m 2  and the backsheet  6  is an impermeable film component or a composite nonwoven/film material  12 . Moreover, as is best seen in  FIG. 2 , the hygiene article comprises lateral cuff elements  14  with thread-like elastification means  15  disposed on their distal edge, fixed on them in the pretensioned condition preferably by hot melt adhesive, which form a lateral leakage barrier. These cuff elements  14  also preferably comprise a nonwoven fabric component  16 , in particular, a hydrophobic spunbonded nonwoven or a spunbond-meltblown (SM) or a spunbond-meltblown-spunbond (SMS) nonwoven laminate with a mass per unit area of 8 to 30 g/m 2 , in particular, 12 to 20 g/m 2 , in particular, 13 to 18 g/m 2 . 
         [0041]    Laterally extending side flaps  22  and  24  are provided in a respective front area  18  and in a respective back area  20 . The side flaps  22 ,  24  extend between topsheet  4  and backsheet  6  and are fixed there by welding or gluing. A weld or glue line is indicated with reference symbol  26 . 
         [0042]    Moreover, the cuff elements  14  of both sides are joined in a first area  27  along a so-called cuff base  28  and in a second area  29  with the nonwoven fabric component  10  of the topsheet  4  by discrete ultrasonic welding points  30  forming a joining pattern. The discrete ultrasonic welding points  30  have a maximum distance between them of 0.1 mm to 2.5 mm in a first area  27  and a maximum distance between them of 4.0 mm to 10.0 mm in a second area  29  and have an area of 0.7 to 0.9 mm 2  in each case. The extent of the cuff base  28  is best visible in  FIG. 1 . For better clarity only,  FIG. 1  does not show the second joining pattern that fixes the right cuff element to the topsheet  4 . The second joining pattern that is not shown is the mirror image of the first. 
         [0043]    It would be possible and advantageous, in an embodiment not shown here, to fix the cuff base  14  directly to the backsheet  6  by means of the joining pattern. This would be advantageous, in particular, if the cuff base  14  were outside the absorption body contour and outside the transverse extent of the topsheet  4 . 
         [0044]    Hygiene article  2  furthermore has a first direction  32  that constitutes the longitudinal direction of the hygiene article and matches the machine direction during production of the hygiene article. In continuous production, the topsheet  4 , backsheet  6 , side flaps  24 , and cuff elements  14  constituting the corresponding webs of flat material therefore extend in this first direction  32 . The cuff base  28  or the series of ultrasonic welding points  30  also largely extends along this first direction  32 . However, as can be seen in  FIG. 1 , the cuff base  28  is, at least in areas, not straight and parallel to the first direction  32 , but extends in the shape of a curve or arc and therefore also has a component in a second direction  34  that is perpendicular to the first direction (transverse direction of the hygiene article). The joining pattern  36  that is at least partially formed by the ultrasonic welding points  30  will be described in detail below. The nonwoven fabric components and/or film components that are permanently joined to each other while the article is being put to its intended use also constitute a composite nonwoven fabric  38 . 
         [0045]    The schematic representation of an ultrasonic welding device designated in its entirety with reference sign  40  in  FIGS. 3 ,  4  illustrates a contour roller  42  that rolls in the machine direction or first direction  32  and a sonotrode  44  that can be excited in the ultrasonic range. The ultrasonic welding device  40  can be integrated into a fast-operating machine for producing modern hygiene articles.  FIG. 3  depicts an ultrasonic welding device with two sonotrodes  44  for producing the welded joint between two cuff elements on both sides, while the device according to  FIG. 4  only shows one sonotrode  44  and is only intended for production of the ultrasonic welded joint with one cuff element. The corresponding further contour roller and sonotrode for the other half could be disposed before, after, or parallel with the first. It is also possible, in the case of the embodiment according to  FIG. 3 , to have a single continuous sonotrode in the second direction  34  instead of two parallel sonotrodes. 
         [0046]    During production of the hygiene articles shown in  FIGS. 1 and 2 , for example, a cuff element  14  and the topsheet  4  in a configuration with one on top of the other would be introduced into the gap of the ultrasonic welding device constituted by the sonotrode and contour roller according to  FIG. 3  to join these components to form the composite nonwoven fabric and to place it on the absorption body  8 . 
         [0047]    On the circumference of the contour roller  42 , numerous protrusions  46  can be seen that are disposed and constituted according to the joining pattern  36  to be produced.  FIG. 5  shows a top view onto the surface of the contour roller  42  viewed in the direction of arrow V in  FIG. 4 . The figure shows the protrusions  46  on the contour roller  42  and the corresponding identical joining pattern  36  produced by them as the roller turns on the flat material web being fed through. A linear or serial configuration of protrusions  46  that constitute ultrasonic welding points  30  of the subsequent cuff base  28  can be seen. Moreover, it can be seen that the distance between the protrusions  46  and the number of protrusions  46  per unit area on the roller surface  42  vary, so that the conditions described in detail below for the relevant joining pattern  36  are met. 
         [0048]      FIG. 6  shows a schematic top view of a joining pattern to illustrate the conceptual division of the joining pattern into 5-mm wide sections  48  in the longitudinal direction  32 . The sections  48  are therefore contiguous in the first direction  32 . Within each 5-mm section  48 , a number of ultrasonic welding points  30  are provided that form for each 5-mm section  48  a proportion A i  of embossed or welded area. If N such 5-mm sections  48  are provided that are conceptually disposed in the first direction  32  from the beginning to the end of the ultrasonic joining pattern  36 , a mean value Ā can be calculated as follows: 
         [0000]    
       
         
           
             
               A 
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         [0049]    It is also possible to calculate a value s from the error sum of squares of the individual A i  values from this mean value Ā according to the following formula: 
         [0000]    
       
         
           
             s 
             = 
             
               
                 
                   1 
                   
                     N 
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                     1 
                   
                 
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         [0050]    From this, it is possible to derive an index I of variation of the ultrasonic welding points in the first direction  32  for the entire joining pattern  36  or the conceptual division into N 5-mm sections  48  as follows: 
         [0000]    
       
         
           
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         [0051]    It was inventively determined that this index of variation of the ultrasonic welding points  30  should be no more than 40% in the first direction  32 . 
         [0052]    Based on  FIGS. 7 and 8 , two different joining patterns of discrete ultrasonic welding points are examined below. As can be seen, it is a joining pattern for fixing cuff elements  14  shown in  FIGS. 1 and 2 , that is, fixing the nonwoven fabric component  16  of these cuff elements  14  to a further nonwoven fabric or film component  10  of a hygiene article. The joining pattern of one of the two cuff elements  14  of the hygiene article was considered. 
         [0053]    The lower part of  FIG. 7  shows along the abscissa the form of the joining pattern under consideration of ultrasonic welding points that have a small distance between them in a first area  27  and a larger distance between them in a second area  29 . The extent of the joining pattern in the first direction (machine direction) is 820 mm, resulting in 164 5-mm sections. Above the said joining pattern,  FIG. 7  shows those welded proportions of the area within each relevant 5-mm section, which are connected to form a curve. There are therefore 164 area proportions A i , one for each 5-mm section. Due to the relatively small radius of curvature of the cuff bases  28  having a high raster density of the ultrasonic welding points, a very high variation of the area proportions can be seen in the first direction  32 . However, this results in the problems described above. The curve shown for the area proportions A i  results in a mean value of 9.01 mm 2  over all N=164 5-mm sections. This results in a value s of 3.85 and in an index I of 42.7%. 
         [0054]    If the joining pattern  36  is divided into a start section  50 , a center section  52 , and an end section  54  that each extend over a third of the extent of the joining pattern  36  in the longitudinal direction, the following values are obtained for these sections  50 ,  52 ,  54  when the N/3 5-mm sections contained in them are each evaluated in isolation: 
         [0055]    Start section: Ā=9.55, s=4.66, I=48.8% 
         [0056]    Center section  52 : Ā=7.62, s=0.71, I=9.3% 
         [0057]    End section  54 : Ā=9.90, s=4.49, I=45.3%. 
         [0058]    Due to this value of the index I of variation of the ultrasonic welding points, a hygiene article with the joining pattern  36  shown in  FIG. 7  would not be in accordance with the invention. 
         [0059]    An inventive joining pattern  36  is shown in  FIG. 8 . The following values are obtained when the N/3 5-mm sections contained in sections  50 ,  52 ,  54  are each evaluated in isolation: 
         [0060]    Start section: Ā=9.56, s=1.67, I=17.5% 
         [0061]    Center section  52 : Ā=7.34, s=0.91, I=12.4% 
         [0062]    End section  54 : Ā=9.25, s=2.33, I=25.1%. 
         [0063]    It can be seen from  FIG. 8 , the welded proportions of the area A i  in the first direction  32  varies very much less than in the joining pattern according to  FIG. 7 . This is achieved with respect to the lowest possible index of variation of the ultrasonic welding points. In particular, it can be seen that a first partial joining pattern  60  that forms a part of a cuff base  28  and extends curved in the shape of an arc is formed from a set of several curves  62 . The term curve is used here for a series of successive discrete ultrasonic welding points  30  (as can be seen in  FIG. 5 ). This set of curves  62  is, for example, disposed in a range of approx. 200 to 270 mm, a small distance apart, and running parallel and largely in the first direction  32 . In the adjoining area (of approx. 200 to approx. 50 mm), the curves  62  are curved in the shape of an arc, and the distance between increases in the first direction  32 . In this way, it is inventively achieved that the area proportions A i  of the 5 mm-sections in the first direction  32  do not vary as much, for example, as in the case of the joining pattern according to  FIG. 7 . In total, a very much lower index of variation of the area seized by the ultrasonic welding points results. 
         [0064]    It is immediately apparent that there are several ways of ensuring that the variation of the area proportions A i  of the 5-mm sections in the first direction  32  is not too large. A first possibility is to keep the radius of curvature of curved partial joining patterns as large as possible, that is, not to permit tight curvature. A further possibility, which is shown in  FIG. 8 , is the formation of curved partial joining patterns in the form of multiple curves or series of ultrasonic welding points, whose distance from each other is especially variable. Also, the distance between the individual ultrasonic welding points, in particular, those of a series could be varied. Also the area of the individual ultrasonic welding points or protrusions on the contour roller could be varied, in particular, additionally. Moreover, the disposition and the distance between the ultrasonic welding points in a second area, that is, where the ultrasonic welding points are further apart, can be varied. 
         [0065]    Finally,  FIG. 8  shows a second partial joining pattern  64  that is substantially straight and extends in the first direction  32 . It is said to extend largely in the first direction  32  if, over a length of about 200 mm in the first direction  32 , an extent in the second direction  34  of no more than 5 mm can be determined. A third partial joining pattern  66  is adjoined to this, which, like the first partial joining pattern  60 , extends curved in the shape of an arc and comprises a set of several curves  62 . It therefore also has a component in the second direction  34 .