Patent Publication Number: US-7712619-B2

Title: Screw cap

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application is a National Stage of International Application No. PCT/EP02/09287, filed Aug. 20, 2002 which claims benefit of German patent application number 101 46 817.2, filed Sep. 20, 2001. 
   FIELD OF THE INVENTION 
   The invention relates to a screw closure for containers, particularly bottles. 
   BACKGROUND OF THE INVENTION 
   Screw closures of the kind addressed herein are known. They either present an inner thread that meshes with the outer thread of a container or they are bayonet locks. In both cases, it is critical that to be opened the screw closure undergo a certain rotatory motion and particularly an axial transverse motion, whereby the closure is lifted from the container or its mouth. It is known to provide such screw closures with a security band, also known as warranty band, which upon the first opening, namely when the screw closure is taken off the container for the first time, is deformed or destroyed in certain regions so that the outer contour is changed. As a result of the changed outer contour, a user can immediately recognize that the container is no longer closed in the original manner and that it possibly has been tampered with. It has been found that the first opening of a screw closure requires rather high opening forces, to prevent easy opening of the closure. Moreover, for many closures of this kind the force needed to reclose the container is relatively high. Finally, in many cases the deformed security band interferes with reclosure. In the known closures, the warranty band is connected to a predetermined breaking line extending all around in the circumferential direction and is provided with a separation line extending vertically thereto. When the closure is opened for the first time, the predetermined breaking line is split in some parts, and the separation line opens up. 
   SUMMARY OF THE INVENTION 
   To reach this objective, we propose a screw closure having the features indicated in claim  1 . It comprises a top from which extends a surrounding skirt which on its inside is provided with a holding device for fixing the screw closure to the container. As mentioned hereinabove, this device can be in the form of a thread or optionally a bayonet lock. As a rule, the screw closure is provided with an internal thread that cooperates with an outer thread on the container. The screw closure is additionally fitted with a security band disposed at the edge of the skirt facing away from the top and which is connected to the screw closure through a predetermined breaking line. The screw closure is characterized by the fact that the security band is provided with at least one elongation zone the extension behavior of which is clearly different from that of the remainder of the security band: The security band is resilient in the region of the elongation zone, particularly across its longitudinal extension, namely across the circumferential direction, so that it exhibits higher flexibility. As a result, less force is needed for the first opening of the screw closure. The same is true for the reclosing of the screw closure. During the first opening, the elongation zone is deformed so that the security band does not interfere when the container is again closed. In this regard, the security band has as a distinguishing feature a closed structure, namely in the undamaged condition it forms a closed band so that during the first closing of the screw closure cannot get interlocked anywhere. The closed band is characterized by high stability despite the elongation zone so that during the first closing of a container the security band remains undamaged with the highest reliability and interference with the closing procedure is practically eliminated. The elongation zone has the distinguishing feature that it confers extensibility to the security band, particularly in the direction perpendicular to the circumferential direction of the screw closure, namely perpendicular to the longitudinal direction of the security band, in other words in the direction of the height of the security band. 
   In a preferred embodiment of the screw closure, the elongation zone extends essentially horizontally. This permits relatively easy and thus inexpensive fabrication of the elongation zone. 
   Preferred is a screw closure with the distinguishing feature that the elongation zone is displaced relative to the predetermined breaking line in the circumferential direction. As a result of this arrangement, there is at least one region, referred to as the overlap region, wherein there is present a predetermined breaking line as well as an elongation zone, said line and said zone being disposed at a distance from each other as seen over the height of the security band. In this manner, an elastic holding band is formed which extends from at the edge of the skirt facing away from the top and as far as the lower region of the security band. The elastic holding band stabilizes the security band relative to the skirt thus keeping the skirt in a desired position. The forces needed for reclosure are thus adjustable, and interference during reclosure can be avoided. 
   Also preferred is an embodiment of the screw closure that is provided with several elongation zones in the region of the security band. In this manner, it is possible to influence the elasticity of the security band in a specific manner so that the opening and reclosing forces can readily be adjusted to a desired low value. 
   Particularly preferred is an embodiment of the screw closure wherein a cut is provided in the region of the security band, namely an elongation cut that acts as an elongation zone. In the region of the cut, which can be intermittent and which entirely or partly passes through the thickness of the security band, the security band has higher elasticity or extensibility so that the elongation zone can be fabricated in simple manner. 
   In another embodiment of the screw closure, the predetermined breaking line does not extend all the way around. In this manner, it is possible to obtain a holding region, referred to as a holding strip, that holds the security band in the desired position. 
   Another preferred embodiment of the screw closure has the distinguishing feature that in the region of the security band, namely between the predetermined breaking line and the edge of the security band facing away from top of the screw closure, there is provided at least one weakening zone preferably extending essentially vertically. It is also conceivable for said weakening zone to be disposed at an angle to the vertical direction. It is essential that in the region of the weakening zone the security band exhibit reduced strength to enable deformation and possibly splitting of the security band to occur in the weakening zone during the first opening. 
   Particularly preferred is an embodiment of the screw closure wherein the weakening zone presents weakening regions that are displaced relative to each other in the circumferential direction. Between the two weakening regions is a connecting strip the strength of which is determined by the length of the weakening regions and by the extent of the displacement. In this manner, the strength in the region of the weakening zone can be predetermined without any particular effort. 
   Other embodiments of the invention are covered in the remaining subclaims. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the following, the invention will be explained in greater detail by way of the drawings in which: 
       FIG. 1  shows a first embodiment of a screw closure in undamaged condition; 
       FIG. 2  is a cross-sectional view along line A-B of  FIG. 1 ; 
       FIG. 3  is a cross-sectional view along line C-D of  FIG. 1 ; 
       FIG. 4  shows a screw closure resting on top of a container after the first opening; 
       FIG. 5  depicts a screw closure on a container, the closure showing a spread security band; 
       FIG. 6  shows a top view of the screw closure of  FIG. 1  in the opened condition; 
       FIG. 7  shows a side view of a second embodiment of a screw closure in undamaged condition; 
       FIG. 8  shows a cross-section along line A-B indicated in  FIG. 6 ; 
       FIG. 9  shows a cross-section of the screw closure shown in  FIG. 6  along line C-D. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The screw closure described in the following has the distinguishing feature that it is lifted from the container mouth during the first opening, namely that it undergoes a transverse motion in addition to the rotatory one. On the inside of the security band is provided an interlocking arrangement that cooperates with an abutment on the container that is to be closed. In this manner, a force is applied to the security band which, on the one hand, acts parallel to the transverse motion and, on the other, brings about a radial widening of the security band. 
   The first embodiment of a screw closure  1  has a top  3  that spans the mouth of the container that is to be closed and from which skirt  5  extends all around so that, overall, a cup-shaped screw closure  1 , also referred to as a screw cap, is formed. On the outside of skirt  5 , there can be provided, as shown here, ribs extending vertically, namely in parallel with the central or rotation axis  7  of screw closure  1 , for the purpose of increasing the ease of gripping screw closure  1 . At edge  9  of skirt  5  that faces away from top  3  there is provided a security band  11  connected to skirt  5  through a predetermined breaking line  13 . Said line is made so that during the first opening security band  11  is detached from skirt  5  in some regions. As a rule, a weakening region is provided or a cut line is made in the wall of the screw closure, namely in the region between skirt  5  and security band  11 , said weakening region or cut line extending through the wall over the entire thickness or only a part of the thickness of security band  11 . If the cut extends over the entire thickness of security band  11  then, as a rule, there are provided several connectors  15  (see  FIGS. 2 and 3 ) which when the cut is made remain essentially undamaged and which span predetermined breaking line  13 . During the first opening, these connectors  15  are torn off so that the predetermined breaking line  13  opens up. 
   The predetermined breaking line  13  can also extend over the entire periphery of screw closure  1 . Preferably, however, it extends over a smaller part of the periphery, for example one amounting to about 240°. Conceivably, it is possible to provide several predetermined breaking lines  13  separated from one another and each extending over a smaller part of the periphery. 
   At a distance from edge  9 , there is provided beneath predetermined breaking line  13  inside security band  11  and approximately parallel to predetermined breaking line  13 , an elongation zone  17  in the region of which the extensibility of security band  11  is substantially higher than in the neighboring region. When—seen in the circumferential direction—there are provided several predetermined breaking lines, then preferably at least one elongation zone  17  is to be assigned to each predetermined breaking line. Elongation zone  17  preferably consists of a linear softer or weakened region of security band  11  and preferably of an elongation cut. This cut can be a through-cut or an intermittent one consisting of individual cut lines. The depth of the cut is selected so that it extends either only through part of the thickness or through the entire thickens of security band  11 , in which case it is necessary to provide a connecting bridge that spans the cut and is torn during the first opening. 
   Elongation zone  17  has the distinguishing feature that—as seen in the circumferential direction—it extends at least over a certain partial region of screw closure  1 . When the closure is opened for the first time, elongation zone  17  is subjected to a force so that it widens essentially transverse to its long dimension. The elongation zone thus extends essentially transverse to the long dimension or circumferential direction of security band  11 , namely in the direction of the height of security band  11  or in the direction of rotation axis  7 . 
   It can be seen from  FIG. 1  that in the embodiment presented here elongation zone  17  extends essentially horizontally and thus practically parallel to predetermined breaking line  13  and/or to the edge  19  of security band  11  facing away from the border. Conceivably, elongation zone  17  can also follow an imagined helical line. 
     FIG. 1  shows that the screw closure is provided with a weakening zone  21  which here comprises a first weakening region  23  disposed between predetermined breaking line  13  and elongation zone  17  and a second weakening region  25  disposed between elongation zone  17  and edge  19 . 
   Weakening zone  21  has the distinguishing feature that its strength is lower than that of the remaining regions of security band  11 . Hence, during the first opening, said security band can stretch or preferably break in the region of weakening zone  21 . 
   In the embodiment presented here, weakening zone  21  extends essentially vertically, namely parallel to rotation axis  7 . It can, however, also be more or less inclined toward said axis. In the embodiment presented here, said zone is—as stated—divided into two weakening regions. These regions—as seen in the circumferential direction—are somewhat displaced, namely they do not form a weakening region that extends vertically through. This is not absolutely necessary. In other words, optionally only a single passing-through weakening region may be provided. Weakening zone  21  can thus consist of several vertical weakening regions or of a single passing-through weakening region. Weakening zone  21  can be in the form of a linear weakening region, namely a thin-walled region, or preferably in the form of a weakening cut or weakening cuts constituting weakening regions  23  and  25 . The cuts can pass through the entire thickness of security band  11  or they can pass through only a part thereof. Conceivably, interrupted, intermittent cuts can also be provided. It is also possible to provide a through-passing cut spanned by a bridge that is torn during the first opening of closure  1 . 
   To reach a defined strength, it is possible, as shown here, to provide two vertical, displaced weakening regions  23  and  25  between which is retained a connecting strip  27  connecting the upper part of security band  11  to its lower part. By the distance seen in the circumferential direction and by the length of weakening regions  23  and  25  as seen in the vertical direction, the strength of connecting strip  27  can be established in a defined manner and thus also the splitting characteristics of security band  11  during the first opening. When in the region of weakening zone  21  there are provided two mutually aligned, merging weakening regions  23  and  25 , the strength in the region of weakening zone  21  can be established by the depth of the cut or by the thickness of security band  11  or else by an intermittent cut provided with at least one bridging strip. 
   The lateral view according to  FIG. 1  shows that security band  11  has two regions between predetermined breaking line  13  and lower edge  19 , namely an upper band region  28   a  and a lower band region  28   b . Between these regions lies elongation zone  17 . 
     FIG. 2  is a cross-sectional view of screw closure  1  of  FIG. 1 . Identical parts bear the same re-ference numerals so that in this respect the reader is referred to the description of  FIG. 1 . 
     FIG. 2  shows that predetermined breaking line  13  does not extend all around but only around a region of about 240°. In a peripheral region of about 120°, edge  9  of screw closure  1  is not weakened or cut. In other words, here there is no predetermined breaking line  13 , either. Here, in this region, skirt  5  is firmly connected to security band  11 , namely to the upper band region  28   a  thereof. 
   The cross-sectional view according to  FIG. 3  shows that elongation zone  17  also does not extend all the way around. In the embodiment presented here, said zone extends over a circumferential angle of about 125°. To the left of elongation zone  17 , a holding strip  29  is formed by the fact that here security band  11  has no predetermined breaking line  13  and no elongation zone  17 . In other words, here security band  11  is fastened directly to edge  9  of skirt  5  of screw closure  1  or forms a single unit with it. Holding strip  29  preferably extends over a region of about 12° to 18° and particularly 15°. 
   Holding strip  29  extends as far as the lower band region  28   a  so that here this region is connected with skirt  5 . 
   On the other side of elongation zone  17  that faces away from holding strip  29  there is located an overlap region  31  wherein there exists, on the one hand, predetermined breaking line  13  and, on the other, elongation zone  17  located at a distance therefrom—as seen in the direction of rotation axis  7 . In this case, predetermined breaking line  13  and elongation zone  17  are disposed from one another at a distance that corresponds to the height of upper band region  28   a.    
   The undamaged regions of screw closure  1  that forms holding strip  29  and overlap region  31  can be established in terms of their width, as measured in the circumferential direction, by appropriate selection of the circumferential length of predetermined breaking line  13  and elongation zone  17 . The overlap extends over a region of 30° to 36° and preferably about 33° or, in other words, over a region amounting to 1/10 to ½ of the circumference. 
   The weakening zone  21  and particularly the second weakening region  25  can be seen in  FIGS. 2 and 3 . 
     FIG. 4  shows screw closure  1  on a container, here on a bottle  33 . It is evident that screw closure  1  has been opened for the first time. Parts coinciding with those shown in preceding figures are indicated by the same reference numerals. In this respect, the reader is referred to the description of  FIGS. 1 to 3 . 
   During the first opening of screw closure  1 , security band  11  was torn in the region of weakening zone  21 , namely in the first weakening region  23  and in the second weakening region  25  as well as in the region of predetermined breaking line  13  and elongation zone  17 . In the region of predetermined breaking line  13 , security band  11  is completely detached from skirt  5 . It is connected to edge  9  of skirt  5  only where there is no predetermined breaking line  13 , for example in the region of holding strip  29 . Elongation zone  17  is slightly spread, because security band  11  was deformed during the first opening. To the left of elongation zone  17  can be seen holding strip  29  wherein the lower part of security band  11 , referred to as lower band region  28   b  namely the region located below elongation zone  17 , is connected with the upper part of security band  11 , referred to as the upper band region  28   a , and with it to edge  9  of screw closure  1 . In the region of the right edge of elongation zone  17  formed by overlap region  31  (see  FIG. 3 ) there is provided an elastic holding band  35  which elastically connects the lower band region  28   b  of security band  11  with the upper band region  28   a  of security band  11  and finally with skirt  5 . 
   Elastic holding band  35  holds the split segment in the region of elongation zone  17  and the segment broken in the region of the predetermined breaking line  13  of security band  11  in a desired spread position so that the forces required for reclosure are minimized and security band  11  is held so that it does not interfere when the container or bottle  33  is reclosed with screw closure  1 . 
   The following is quite evident. The width of holding strip  29 , as seen in the circumferential direction, is defined by the distance of the left end of elongation zone  17  to weakening zone  21 . The size of overlap region  31  as measured in the circumferential direction defines the length of the elastic holding band  35 , and the distance between elongation zone  17  and predetermined breaking line  13  as measured in the vertical direction determines the height and thus the strength of elastic holding band  35  and, hence, also the elasticity of security band  11 . 
   In other words, the strength of holding strip  29  and that of elastic holding band  35  can thus be established in simple manner, the selection of the material constituting security band  11 , of course, also playing an essential role in this regard. 
     FIG. 5  shows once again screw closure  1  placed on a bottle  33 . Here security band  11  is bent approximately linearly against its inherent elasticity. In other words, it no longer extends along a bent contour around container  33 . This arrangement of security band  11  is not the one which said band assumes in a regular functional position, but serves only to explain the configuration of screw closure  1 . Identical parts are indicated by the same reference numerals so that for a description the reader is referred to the preceding figures. 
   Security band  11  is thus provided with two band regions. An upper band region  28   a  follows directly predetermined breaking line  13 . A lower band region  28   b  reaches as far as edge  19  of security band  11 . To the right of elongation zone  17 , the upper and lower region of security band  11  are connected to each other or form a single unit. In other words, here there are no weakening or elongation zones. 
   At the right, free end of security band  11  can be seen weakening zone  21  which extends around the upper, first weakening region  23  in upper band region  28   a  and the lower, second weakening region  25  displaced in circumferential direction in the lower band region  28   b . Both weakening regions  23  and  25  are split when screw closure  1  is opened for the first time so that here a step is almost formed. Weakening zone  21  as a rule splits already during the first opening of screw closure, and at the latest when screw closure  1  is lifted from the container mouth. 
   It is evident from  FIGS. 1 to 5  that the outer surface of upper band region  28   a  of security band  11  as applied widens in slightly conical manner starting at skirt  5  and that lower band region  28   b  of security band  11  has a cylindrical shape. It is quite conceivable that the conical widening also extends over the lower band region  28   b  of security band  11  or that the upper band region  28   a  of security band  11  can have an essentially cylindrical shape. 
   The total height of security band  11  determines its strength. The height of upper band region  28   a  amounts to about one third of the total height and in particular from 0.3 to 0.33 times the total height. For a total height of security band  11  of about 4.2 mm, the height of upper band region  28   a  is then about 1.26 mm to about 1.4 mm. The connection of security band  11  to skirt  5  of screw closure  1  or to its edge  9  occurs via elastic holding band  35  and also via holding strip  29 . These connections also predetermine the breaking properties of security band  11  overall and in the region of elongation zone  17  during the first opening of screw closure  1 . These properties also depend on the material constituting screw closure  1 . 
   It is important that elongation zone  17  and weakening zone  21  reduce the overall strength and increase the elasticity of security band  11  so that less strength is needed to open screw closure  1  for the first time. The elasticity of security band  11  can be influenced by the length of elongation zone  17 . Moreover, the free-standing region of security band  11  is kept in spread position by elastic holding band  25  so that a first opening and thus tampering can be reliably recognized, the reclosing forces can be reduced and security band  11  does not interfere with reclosure. 
     FIG. 6  is a top view of screw closure  1  as explained with the aid of  FIGS. 1 to 5 . Identical parts are indicated by the same reference numerals so that for a description the reader is referred to the preceding figures. 
   Screw closure  1  has already been opened so that, as shown in  FIG. 4 , security band  11  is radially split. This readily indicates to the user that tampering with and a first opening of screw closure  1  had taken place. 
   It is evident that security band  11  is spread to an extent such that it no longer interferes with the reclosure of the container. Free end  37  can support itself on the lower edge  9  of skirt  5  and is thus held reliably in the spread position. Moreover, security band  11  is kept reliably in the spread position by elastic region  39  formed by lower band region  28   b  of security band  11  between holding strip  29  and elastic holding band  35  so that already for this reason said security band does not interfere with reclosure, and the forces required for reclosure are clearly reduced. The elasticity of the fixed, elastic region  39  is determined by the length of elongation zone  17  and/or the axial distance of elongation zone  17  from edge  9  of security band  11 . 
   The reason why security band  11  is held very well in the spread position by elastic region  39  is that at one of its ends elastic region  39  is supported at holding strip  29 , namely it is also connected directly with skirt  5  of screw closure  1 . 
   The purpose of elastic holding band  35  is, on the one hand, also to hold security band  11  in a more or less spread position, as can be seen from  FIG. 6 . On the other hand, however, it also serves to maintain the spreading in the region of elongation zone  17  that occurred during the first opening, as can be seen from  FIG. 4 . In this case, as shown in  FIG. 4 , the lower band segment  28   b  of security band  11 , namely elastic region  39 , is kept at a distance from its upper band region  28   a  so that by this axial spreading, too, tampering with and a first opening of screw closure  1  can readily be recognized by a user. 
   Unlike in  FIG. 6 , security band  11  can with its free end  37  also lie slightly inside the outer boundary line of screw closure  1 . It is essential that said band be held over its entire length at a radial distance from skirt  5  of screw closure  1  so that the interlocking and fastening devices, not shown here, disposed on the inside of security band  1  and which can have the form of barbs do not interfere with reclosure of the container and the reclosing forces are thereby substantially reduced. The fastening devices can be oriented and disposed relative to predetermined breaking line  13  and particularly relative to elongation zone  13  so that security band  1  is stabilized during the first attachment of screw closure  1  and during transport of the closed container. 
   It can thus be seen from  FIG. 6  that elastic region  39  is held at a radial distance from skirt  5 . The distance of the remaining security band  11  can be increased further in the radial direction by the spreading forces of elastic region  39  and by the holding forces of elastic holding band  35 . We found that the barbs provided on the inside of security band  11  are in their original position only in the region of holding strip  29 . The barbs on the inside of elastic region  39  and on the inside of the remaining security band  11  are displaced radially outward. As a result, as already stated, during closing, namely while the closure is being screwed on, the barbs of screw closure  1  cannot interfere and the reclosure forces are clearly reduced. 
     FIG. 7  shows a modified embodiment  1 ′ of the screw closure, similar to the one explained by way of  FIGS. 1 to 6 . Identical parts are indicated by the same reference numerals so that for a description the reader is referred to the preceding figures. 
   Screw closure  1 ′ also has a top  3  from which extends skirt  5 . On edge  9  of said skirt, facing away from top  3 , is attached a security band  11  which via a predetermined breaking line  13  is connected to edge  9  and has an elongation zone  17 . In the embodiment of screw closure  1 ′ presented here, as in the embodiment presented hereinabove, predetermined breaking line  13  does not have to extend all the way around and—and this also applies to the above-described embodiment—several individual segments of a predetermined breaking line can be provided. The same is also true for elongation zone  17  in both embodiments. In other words, in both embodiments there can be provided one or more elongation zones  17  as will be explained in greater detail by reference to  FIGS. 8 and 9 . 
   The essential difference of the embodiment of screw closure  1 ′ presented in  FIGS. 7 to 9  is that it does not have a weakening zone which in the afore-described embodiment is identified by reference numeral  21 . 
   In the embodiment presented here, predetermined breaking line  13  extends essentially horizontally, as does elongation zone  17 . For this embodiment, as for the afore-described one, however, the predetermined breaking line and the elongation zone can extend at an angle inclined toward the horizontal or they can follow an imagined helical line. It is essential that predetermined breaking line  13  and elongation zone  17  intersect in a region Ü, namely that an overlap region  31  is formed, as was already explained by way of  FIG. 3 . The length of the intersection in region Ü, indicated by a double-headed arrow, can be selected within a wide range as can the axial distance, as measured in the direction of rotation axis  7 , between predetermined breaking line  13  and elongation zone  17 . As a result of this configuration, here, too, an elastic band  35  is formed which after the first opening of screw closure  1 ′ connects an upper band region  28   a  of security band  11  with the lower band region  28   b  and which after the first opening holds the lower band region  28   b  of security band  11  in a spread position as can be seen in  FIG. 4 . Lower band region  28   b  of security band  11  is thus radially spread and disposed at a distance from the upper band region. Moreover, elongation zone  17  is kept in the spread condition so that tampering and a first opening are readily recognizable. 
   A second elongation zone  17   a  can be seen at the left end of predetermined breaking line  13  presented in  FIG. 7 . In principle, first elongation zone  17  could extend around a length which would make elongation zone  17   a  its second end, namely the end of elongation zone  17  facing away from overlap region  31 . Here, however, it has been assumed—as can be seen in FIG.  9 —that two elongation zones  17  and  17   a  are present. The right-hand end of elongation zone  17   a  does not intersect the left-hand end of predetermined breaking line  13  so that here the lower band region  28   b  of security band  11  is connected, via its upper band region  28   a , with edge  9  of skirt  5  of screw closure  1 ′ thereby forming holding strip  29 . By means of holding strip  29 , the lower band region  28   b  can, as described hereinabove, be supported reliably on skirt  5  so that the desired spreading forces are ensured. 
   Screw closure  1 ′ is similarly configured on the opposite side, namely on the side hidden in  FIG. 7 . This means that elongation zone  17   a  has a region  31  where it overlaps with a second predetermined breaking line, not shown, so that here, too, an elastic holding band  35   a  is formed. In other words, there can be provided several elongation zones disposed at a distance from each other in the circumferential direction. Here, as in the first embodiment, it is possible to provide several elongation zones distributed over the height of security band  11 . 
     FIG. 8  is a cross-sectional view of screw closure  1 ′ along line A-B of  FIG. 7 . It can be seen here that the predetermined breaking line  13  shown in  FIG. 7  extends in this case over a circumferential region of, for example, about 100°. On the opposite side there is provided a centrosymmetric predetermined breaking line  13   a.    
   At one end, here the right end, of predetermined breaking line  13 ,  13   a  there is provided overlap region  31 ,  31   a  which in this case extends over a region of, for example, about 30°. It is shown in  FIG. 8  that over a region of about 10° there is no intersection between predetermined breaking line  13 ,  13   a  and elongation zone  17 ,  17   a  so that holding strip  29 ,  29   a  is formed. 
     FIG. 9  shows a cross-section of screw closure  1 ′ along line C-D of  FIG. 7 . Here it can be seen that elongation zones  17  and  17   a  extend over a circumferential region of about 100° and that they are disposed symmetrically relative to one another. 
   Overall, the following is obvious. In both embodiments of screw closures  1 ,  1 ′, security band  11 , which via a predetermined breaking line  13  is connected to edge  9  of skirt  5 , is provided with at least one elongation zone  17 . Predetermined breaking line  13 , which does not extend all the way around, in some regions intersects elongation zone  17  which, too, does not extend all the way around, so that there is provided at least one overlap region  31 . Through elongation zone  17 , security band  11  in this fixed, namely radially not freely spread region, is provided with an elasticity that facilitates the reclosure of a container. In overlap region  31  is formed an elastic holding band  35  that holds security band  11  after the first opening of screw closure  1 ,  1 ′. On the one hand, by means of elastic holding band  35 , in the region of elongation zone  17 , a lower elastic region  39  of security band  11  facing away from skirt  5  is kept in spread position at an axial distance from the upper region of security band  11 . On the other hand, elastic holding band  35  can hold a security band  11  spread in the circumferential direction at a radial distance from skirt  5 . 
   Security band  11  is spread particularly when a weakening zone  21  is provided, as explained for the embodiment presented by way of  FIGS. 1 to 6 . But even without such a weakening zone, as explained for the embodiment presented in  FIGS. 7 to 9 , and without the spreading of security band  11 , elongation zone  17  in security band  11  provides a reliable indication of tampering with and first opening of screw closure  1 . Moreover, in all embodiments, security band  11  is weakened by elongation zone  17  so that the additional extension reduces the forces required for a first opening as well as those required for reclosure. 
   Beneath elongation zone  17  of both screw closures  1  and  1 ′, in the lower band region  28   b , there is formed elastic region  39  which not only is spread axially but also radially, as explained in greater detail by reference to  FIG. 6 . By this radial spreading, in both embodiments the barbs located on the inner surface of elastic region  39  are also displaced radially outward so that they cannot interfere with the reclosure of a container. At the least, the forces for reclosure are much reduced. 
   It can also be seen from  FIG. 4  that the lower band region  28   b  located below elongation zone  17 , namely, in particular, elastic region  39  is swiveled downward. By the connection of elastic region  39  to holding strip  29 , on the one hand, and to elastic band  35 , on the other, a tilting motion results whereby the barbs located on the inner surface of elastic region  39  are also swiveled. Also as a result of this swiveling, the barbs do not interfere with the reclosure of a container, and at least the forces required for reclosure are reduced. 
   The basic principle of the additional elongation zone described here, as explained by way of  FIGS. 1 to 6 , is realized with a single elongation zone  17 . It is also possible, however, to provide several elongation zones as seen in the circumferential direction and over the height of security band  11 , as explained by reference to  FIGS. 7 to 9 , and which also applies to screw closure  1 . When several elongation zones  17  are provided over the height of security band  11 , then overlap regions can be provided between them so that, correspondingly, several elastic holding bands also are formed. It is also possible that at one or more elongation zones at both ends there are overlaps with the predetermined breaking line and/or the elongation zones so that elastic holding bands are formed on both sides. Such an arrangement provides especially high extensibility of security band  11  in the direction of the rotating axis of screw closure  1 , namely over the height of security band  11 . Here, the aforedescribed support of an elastic region  39  is, of course, not as strong. In other words, in this case the spreading can be reduced if the holding strips are not reinforced. The horizontal regional support of security band  11  by one or, in particular, several elongation zones, can bring about increased extensibility in radial and circumferential direction whereby the first opening and the reclosure are additionally facilitated. 
   The advantages of screw closure  1  and  1 ′ described here arise particularly when a weakening zone  21  is provided which extends essentially transverse to the extension of security band  1 , namely in the vertical direction. In this case, one or more weakening regions can be provided. In the embodiment of  FIGS. 1 to 6 , two weakening regions  23  and  25  have been explained. The splitting of security band  11  in the region of weakening zone  21  causes an additional splitting in radial direction which makes it very easy to recognize a first opening and tampering. It is evident from embodiment 1′, however, that weakening zone  21  optionally can also be omitted without losing the advantages of the additional elongation zone. Tampering and first opening are reliably indicated also by the axial deformation or widening of security band  11  alone. The reliability of such indication is further increased by the fact that a radial widening takes place 
   Expansion zone  17  and optionally  17   a  can be formed in any desired manner. Conceivable is a linear weakening of the material. In particular, however, an elongation cut in security band  11  is provided. The same is true for predetermined breaking line  13  which can be made in screw closure  1 ,  1 ′, but preferably consists of a cut line. In both the case of predetermined breaking line  13  and elongation zone  17  or  17   a , the cut can penetrate through the entire thickness of security band  11  or only through part of it. Conceivably, intermittent cuts, namely successive cut lines, can be made to provide the predetermined breaking line or elongation zone. 
   The same is true for the weakening zone  21  which can have one or more weakening regions. Note also that unlike in the embodiment explained by reference to  FIGS. 1 to 6 , there can be provided several such weakening zones  21 . The segments of the split security band  1  formed during the first opening are then formed in a manner similar to the security band that was explained by reference to  FIGS. 1 to 6 . Hence, the number of elongation zones must be adapted to the number of weakening zones in order to be able to form at least one holding strip and at least one elastic holding band for each security band region. 
   From all this, it is evident that holding strip  29  which cooperates with elastic region  39 , is of critical importance for the advantages described here. Via holding strip  29 , elastic region  39  can be supported directly on skirt  5  of screw closure  1  so that, on the one hand, elastic region  39  is held in its axially as well as radially spread position. On the other hand, by elastic region  39  being supported on holding strip  29 , it can be ensured that the remaining region of security band  11  will be held in a spread position. In this manner, as described, the barbs on the inside of security band  11  are kept at a distance such that the forces needed to reclose a container are greatly reduced. 
   The function of holding strip  29  can also be seen in connection with weakening zone  21 : Holding strip  29  holds security band  11  attached to skirt  5  in the region of weakening zone  21  so that during the first opening of screw closure  1  weakening zone  21  is reliably split or weakened to the extent that it will break the first time screw closure  1  is removed. The strength of holding strip  29  is ensured by the fact that on the side facing weakening zone  21  of holding strip  29 , the horizontal predetermined breaking line  13  that spans weakening zone  21  extends into holding strip  29  only in a very small region. Preferably, care is taken that predetermined breaking line  13  extends into holding strip  29  only just a little so that the region of holding strip  19  weakened by predetermined breaking line  13  amounts to a maximum of 1/60 of the circumference of screw closure  1 . If predetermined breaking line  13  penetrates further into holding strip  29 , then during the first opening of screw closure  1 , the region of holding strip  29  facing weakening zone  21  could be bent away downward so that weakening zone  21  would not split reliably. For this reason, the region weakened by predetermined breaking line  13  in the region of holding strip  29  is limited to the above-indicated value. 
   On the other side of holding strip  29 , namely on the side facing away from weakening zone  21 , elongation zone  17  penetrates slightly into holding strip  29 . In other words, said strip is weakened, on the one hand, by a small region of predetermined breaking line  13  and, on the other, by a region of elongation zone  17  extending into holding strip  29 . It is necessary to ensure that in the region of holding strip  29  the predetermined breaking line  13  and elongation zone  17  are disposed at such a distance from one another that during the first opening holding strip  29  does not break. The distance from the first weakening region  23  of weakening zone  21  to elongation zone  17  amounts to 1/20 to 1/30 of the circumference of screw closure  1 , as measured in the circumferential direction. By the afore-indicated minimal residual width of holding strip  29 , it is also ensured that holding strip  29  can provide sufficient holding forces for elastic region  39 . 
   Preferably, screw closure  1 ,  1 ′ is made of a plastic material and particularly by the compression molding or injection molding process. This embodiment has the distinguishing feature that the screw closure then consists entirely of a plastic material. It is also possible, however, to combine a security band  11  made of plastic material with a screw closure the top and skirt of which consist of a deep-drawable material, particularly of metal. Aluminum has been found particularly well suited for screw closures of the kind discussed here. The security band can be connected in the known manner with the edge of the skirt facing away from the top and can be configured as explained with reference to  FIGS. 1 to 9 . In an embodiment of this kind, too, it is possible to realize the advantages described herein even if security band  11  consists of a plastic material. 
   Screw closure  1 ,  1 ′ described herein is suitable for disposable as well as reusable containers of all kinds made of glass, PET and the like, and particularly for bottles.