Sealing pattern for tampon overwrap

Technical field The present invention relates to a sheath for a single absorbent article, such as a tampon. In particular, the invention relates to sealing the tampon sheath so that the seal formed does not hinder the operation of the opening mechanism that extends around the periphery of the absorbent article.

Background Art [0002] Individual absorbent articles for personal care products are protected from environmental influences by sheets of material, commonly referred to as casings or casings. In particular, tampons use casings in which each tampon is enclosed in a separate immediate packaging, which can then be sold in larger quantities, often in a box. [0003] Tampons are generally divided into two categories: tampons with an applicator and tampons without an applicator. The applicator tampon casing is usually elongated, loosely fitted, sealed along the flanges, or has spline seams at the ends, with a small incision or notch at one end that the user uses to open by tearing the sheath in the longitudinal direction. The casing intended for a tampon without an applicator is usually tightly fitted, often in contact with the outer surface, completely around its periphery. Typically, a tampon shell without an applicator resembles a tube in which two longitudinal edges overlap. The casing is tightly closed at the insertion and removal end. This longitudinal fold is also tightly closed, usually with the use of heat. This tight wrap can be helpful in maintaining the shape of the tampon and can prevent deformation.

[0004] Examples of casing sealing for both tampons without an applicator and tampons with an applicator can be found in US 4,170,305 (Hull et al.); WO 03/082174 (Schoelling et al.); US 6,955,665 (Domeier et al.); US, 7,101,358 (Domeier et al.) And US 2008/0118679 (McConnell et al.).

[0005] US 4,170,305 discloses a sheath for a cylindrical body that is tightly wrapped, transparent, dustproof and easy to open. The casing has two perforation zones and a double curl in such a way that these zones are shifted so as to close the passage to the interior of the product. The ends of the casing are sealed by means such as hot welding. The tampon is unwound by simply raising and gripping the flap, so that the two layers come together, separating the casing into several pieces. The casing runs along at least twice around the circumference of the tampon body.

[0006] WO 03/082174 discloses packaging material having at least one weakening line. After the line is damaged, the casing can be peeled off the product, preferably in one piece. The end points of the packaging material sheet can be reinforced to prevent the packaging material from tearing beyond the end points. [0007] US 6,955,665 discloses a sheath for individually packaged tampons. The casing has opening means that constitute at least one weakness line that does not run around the entire wrapped tampon when considering its length or circumference. Therefore, the casing was not separated into several pieces of casing material when the casing was opened, which was facilitated by tearing along the weakening line.

[0008] US 7,101,358, in turn, discloses a sheath for separately wrapped tampons that includes a weakening line that has opening means including a stop. The opening means is a tear-opening strip, and the stop prevents the tear-opening strip from separating from at least one segment of the casing material that is formed after opening the casing. When the sheath is formed by closing the superimposed material, a seam is formed in the sheath areas. The tear-opening strip can run around the entire tampon longitudinally or around the entire tampon circumference or both. The stop may substantially coincide with at least part of the seam.

[0009] Document US 2008/0118679 discloses a sheath that provides predictable and easy opening, discrete removal and the ability to remain in one piece after opening. The casing includes one or more lines of weakness which may be at an angle to the longitudinal axis of the casing. The weakening line may run around less than about 95% of the circumference and may have an initiation point. The casing may have a tight seal at the back or side.

[0010] According to the present invention, although the line of weakness extends completely around the wrapped tampon, the sheath remains in one piece after opening. This overcomes some of the disadvantages of the prior art above, including offering the user a hygienic, wrapped tampon, an easy way to remove the tampon from the casing, waste in one piece, and the need for less tampering with the casing. This is accomplished by sealing the edges of the tampon shell so that the perforations forming the opening mechanism are not blocked or their operation is otherwise compromised. This allows the casing to be easily opened to remove the tampon that surrounds it, without the risk of splitting the casing into multiple pieces of material.

Summary of the Invention [0011] We have developed a packaged, oblong vaginal device that allows the device to be removed from the sheath while maintaining the sheath as a single piece of material.

[0012] Tampons are packaged in a substantially cylindrical sheath formed of flexible sheet material that is closed by one or more connection zones having one or more slits cut through by a weakening line.

[0013] In one embodiment of the invention, the tampon is wrapped in a substantially cylindrical sheath formed of flexible sheet material, which is closed by a single connection zone having one gap through which a weakening line extends. The casing is closed at both ends and has an elongated seam area in which overlapping fragments of flexible sheet material are connected. The longitudinal seam area includes a substantially longitudinal connection zone along with a first longitudinal edge and a second longitudinal edge that defines the seam area. The weakening line has a first end located in the seam area at the first longitudinal edge of the substantially longitudinal zone of the sheet joint. substantially longitudinal distance from the first end of the package in the form of a casing; extends through the gap in the substantially longitudinal connection zone and to the second longitudinal edge of the substantially longitudinal connection zone; it extends substantially circumferentially around the casing; passes through the gap in the substantially longitudinal connection zone and ends at the second end located in the seam area at the second longitudinal edge of the substantially longitudinal connection zone, the substantially longitudinal connection zone comprising a discontinuous seal line having a first seal portion, a second seal portion and a seal gap, constituting the gap through which the weakening line runs, wherein the first and second sealing portions run longitudinally towards the discontinuous seal line.

[0014] In another embodiment of the invention, the tampon is wrapped in a substantially cylindrical sheath formed of flexible sheet material, which is closed by two connection zones, each having one slot, with a weakness line running through the slots. The casing is closed at both ends and has an elongated seam area in which overlapping portions of flexible material are joined. The elongated seam area comprises a first, connection zone, which defines the first side of the seam area, and a second, substantially elongated, connection zone opposite the first , a substantially longitudinal connection zone that defines the other side of the seam area. The weakening line has a first end positioned in the seam area at a first distance from the first end of the package in the form of a casing and adjacent the first substantially longitudinal connection zone; extends through the gap in the second substantially longitudinal connection zone; it extends substantially circumferentially around the casing; extends through the gap in the first substantially longitudinal connection zone at a second distance from the first end of the sheath / package and ends at the second end located within the seam area adjacent the second substantially longitudinal connection zone. [0015] In another embodiment of the invention, the tampon is wrapped in a substantially cylindrical sheath formed of flexible sheet material, which is closed by three connection zones, each of which has at least one slit, with a weakness line running through the slits. The casing is closed at both ends and has an elongated seam area in which overlapping pieces of flexible material are connected

The longitudinal seam area comprises a first, connection zone that defines a first side of the seam area, and a second, substantially longitudinal connection zone opposite the first, substantially longitudinal connection zone that defines a second side of the seam area, as well as a third, substantially longitudinal zone connections located between the first and second substantially elongated connection zones. The weakening line has a first end positioned in the seam area at a first distance from the first end of the package in the form of a casing and adjacent the second substantially longitudinal connection zone; extends through the slots in the first and third substantially longitudinal connection zones; it extends substantially circumferentially around the casing; extends through the slots in the second and third substantially longitudinal zones of the sheet joint. substantially longitudinal at a second distance from the first end of the sheath / package and ends at the second end located within the seam area adjacent the first substantially longitudinal connection zone.

[0016] In another embodiment of the invention, the method of packaging a tampon includes the steps of providing a casing blank comprising flexible sheet material of a certain length and width having at least one weakness line extending across substantially the entire width; shaping the shell blank to form a shell tube having a first and second end, with a length corresponding to the length of the half half-shell, and having an overlapping seam overlapping area having two layers of flexible sheet material; forming an elongated seam within the seam area by joining parts of two layers together while maintaining a specific model; closing the first end of the tube; inserting the tampon into the tube; and closing the second end of the tube. The sheath tube comprises a first, substantially longitudinal connection zone, which defines the first side of the seam area, and a second, substantially longitudinal connection zone, opposite the first, substantially longitudinal connection zone, which defines the second side of the seam area. The second substantially longitudinal connection zone has a gap formed therein near its first end corresponding to the first end of the sheath tube, and the first substantially longitudinal connection zone has a gap formed therein near its first end corresponding to the first end of the sleeve tube. The gap in the second substantially longitudinal connection zone is closer to the first end of the sheath tube than the gap in the first substantially longitudinal connection zone. The weakening line has a first end located in the seam area adjacent the first substantially longitudinal connection zone, extends through the slots in the second and first substantially longitudinal connection zone, and has a second end located in the seam area adjacent the second substantially longitudinal connection zone.

Description of the figures [0017] Fig. 1 is a perspective view of an example of a packed tampon in accordance with the prior art; Figure 2 is a perspective view of the tube used to make the tampon casing according to the prior art; Figure 3 is a perspective view of the welder used to manufacture the tube shown in Figure 2; Figure 4 is a top view of a sheet of material for forming an embodiment of the present invention; FIG. 5 is a perspective view of a packaged tampon made of a sheet of material as seen in Fig. 4; Figure 6 is a perspective view of a tube having a seal model made in accordance with one embodiment of the invention;

Figure 7 is a perspective view of a tube having a seal model made in accordance with another embodiment of the invention;

Figure 8 is a perspective view of a tube having a seal model made in accordance with the present invention; Figure 9 is a perspective view of a tube having another seal model made in accordance with the present invention, which tube is made of a sheet of material in accordance with Figure 4; and Fig. 10 is a perspective view of the welder used to manufacture the tube shown in Fig. 9; FIG. 11 is a perspective view of a welder in an alternative embodiment of the present invention;

Figure 12 is a perspective view of the tube produced using the welding machine shown in Figure 11;

Figure 13 is a top view of a sheet of material for forming an alternative embodiment of the present invention having coated, non-sealable areas;

Figure 14 is a top view of a sheet of material for forming an alternative embodiment of the present invention.

Detailed Description of Preferred Embodiments [0018] Absorbent tampons typically include elongated packed absorbent structures, such as substantially cylindrical masses of absorbent material, having a longitudinal central axis and a radius that defines the outer peripheral surface of the tampon. Tampons are often formed by obtaining first a shaped mass of absorbent material, called a tampon blank. The blank may be in the form of a roll of sheet material, a continuous section of absorbent material, a mass of any or substantially uniformly oriented absorbent material, prepared independently, or a cast mass of absorbent material and the like.

[0019] The tampon blank is relatively unpackaged and has a relatively low density. It is then pressed to form a product with overall dimensions smaller than that of the blank before use.

The packed tampons may have a substantially uniform density throughout the tampon or may have areas of different density as described in US Patent Applications, Friese et al., US Pat. No. 6,310,296, and Leutwyler et al., US Pat. No. 5,911,712. Tampons usually include a casing (or are subjected to other surface treatments) and a removal string or other removal mechanism.

[0020] By "outer surface" of a tampon here is meant the visible surface of the packed tampon prior to its use or expansion.

[0021] By "length" of a tampon is here meant a linear dimension of the tampon along its largest dimension.

[0022] By "circumference" of a tampon here is meant a distance measured along the outer surface of the tampon in a part of the outer surface that runs in a plane substantially perpendicular to the dimension of the length of the tampon. In other words, the length of the tampon runs along the x axis of the Cartesian coordinate system, and the circumference is typically in the y plane from the said coordinate system.

[0023] As used herein, the terms "weakening element" and "weakening line" should be understood as a series of weakening points arranged in a row. These points of weakness may be perforations, areas of reduced thickness, gaps, score lines, areas of reduced density, and more. [0024] The term "sheath" as used herein refers to a structure that is formed from a sheet of material and which essentially surrounds a given vaginal device. The term "vaginal device" can mean those devices that are intended to be placed inside the vaginal canal, such as a tampon or device used for people with urinary incontinence / pessary. The sheath has two ends, each of which is assigned to the end of a wrapped tampon. Typically suitable the casing materials for use in the present invention are flexible polymeric films The film used can be of any thickness.

[0025] An example of a packaged tampon 6 known from the prior art is shown in Figure 1. The packaged tampon 6 comprises a tampon 10 inside the casing 30. The tampon 10 comprises a packed, longitudinal absorbent structure 12 having a predetermined length, insertion end 14, removed end 18 and middle part 16, located between the inserted and deleted ends. The output tip may contain a string (not shown). The tampon 10 has an outer surface 20 and a circumference 102 that defines a 360 ° angle around the tampon.

[0026] In the example shown in Fig. 1, the sheath 30 has an opening mechanism. In this example showing the prior art, the sheath includes a finger-raised flap 32 that allows the user to open by tearing the sheath along the perforated lines 34 and 36 that run around the sheath. Usually this type of opening mechanism results in the casing being torn apart into many parts: a central part with a width corresponding to the size of the finger lift, a part covering the inserted end and a part covering the removed end. When the wearer opens the sheath by lifting and separating the flap lifted with her finger, she may additionally be forced to tear off the remaining parts. This remains an inconvenience for the wearer because she must then use both hands to unwrap the tampons, while dealing with many parts that can accumulate static electricity, causing these parts to stick to the hands, fingers and / or tampon. This can increase the risk of the casing remaining on the tampon when it enters the body. This remaining portion of the sheath may detach from the tampon when it absorbs fluid, resulting in remaining in the body until removed by the user.

[0027] This uncontrolled opening of the casing may also occur with thinner packaging materials in which the tear may not follow a particular path along the weakening line, and may also result in many pieces of damaged casing.

[0028] The casings can generally be made of a sheet or one connected piece of sheath material, however, the sheath can also be made of multiple pieces of material sufficiently connected together such that they will essentially act as a single sheet or one connected piece of sheath material. In Fig. 1, the material was combined by any means known in the art. The place of connection of the material is commonly called a seam. The casing may be transparent, colored or have a print that may contain opening instructions (arrows, dashed lines and the like).

[0029] In the example demonstrating the prior art (shown in Fig. 2), a tube was used to form a sheath that includes a seam formed by the connection zone. The connection zone connecting the material layers is essentially a single continuous line 76. Fig. 2 shows a tube having this type of seam (a tube that can be further formed into a tampon shell). To form such a seam, a welding machine 74, as shown in Figure 3, can be used. This welding machine has one sealing surface 78 that forms a single, continuous airtight seal in the casing material when it contacts the material. The sealing surface 78 substantially conforms to the cylindrical shape of the tampon without an applicator. The sealing surface formed by this welder can be any width, creating a wide seam that is difficult to tear across.

[0030] Fig. 4 is a casing sheet, an example of which is used to produce one embodiment of the present invention.

[0031] As shown in this drawing, the sheath may be formed from a rectangular sheet of material 40 having an insertion end 42, removed end 46, middle portion 44, first margin 52, second margin 54, first edge 48 and second edge 49. Middle portion 44 further includes an upper central area 44a that is closer to the insertion end, and a lower central area 44b that is closer to the removal end. When sheet 40 is formed into a tube, margins 52 and 54 overlap. These margins can be joined together in the longitudinal direction (as a result of which a seam is obtained along the side of the tampon). The sealing of the margins creates a double-layer seam. Finally, the tube structure is closed at both ends with a tampon inside. As a result, a package is obtained in which the lower part of the package is formed from the lower central region 44b of the sheath material sheet and the central part of the package is formed from the upper central region 44a of the sheet.

[0032] In this embodiment, a single weakness line 60, made of the weakening elements 66 and 63, is used. In the embodiment of figure 4, the weakening element 66 is shown as inclined or running diagonally. The tampon placed in the obtained casing is shown in Fig.

5.

[0033] Furthermore, by using a certain ratio of weakness length: solid in certain areas of the casing, a casing can be provided that opens completely around the tampon, remains in the form of a single element, and allows hygienic removal of the tampon from the casing. For example, using a gap or perforation having an open section as a weakening point, it has been found that a ratio of approximately, for example, about 1: 1 - for example about 2: 3 to about 3: 2, preferably 4: 5 to about 5: 4 in length an open section to a fixed part in the lower central area 44b (including the weakening element 63) and the ratio, for example, about 2: 1 or more allows the user to grasp the insertion and removal end using the fingers of both hands, twist and / or pull the sheath and open the upper middle area 44a with a slight force. The user may then slightly twist the sheath to further separate the weakening line 60 toward the lower center area 44b. The user can then pull to remove the casing from the ground with one hand while holding the tip inserted. The casing at the insertion end remains intact and the user's fingers are not in contact with the tampon. The casing remains as one piece of material. Because the perforations in the upper central region 44a have a larger open segment compared to the open segment of the lower central region 44b, the weakening line 60 will first open in the upper central region 44a before it opens in the lower central region 44b. The insertion of the tampon remains in the casing until the user completely removes the casing (just before entering the body). Of course, the twisting steps to open and pull off the casing can be carried out in one step. Although the above information shows an example of a relationship for one type of material, the choice of material and weight can change the ratio of open area to solid area. The above information contains examples of the length of open sections, fixed sections and relations between them. They can be balanced so that the weakness line 60 formed is stronger at the removed end and weaker at the center of the packaged tampon. Any ratio that allows this to be achieved for a particular material and size of tampon is acceptable, however, the weakening line should be optimized to give the casing the ability to resist 1) the internal swelling forces of the tampon, given that the compressed fibers tend to expand over time time, 2) external forces from the environment (such as those exerted on the casing when the user stores the tampon in a purse or pants pocket), without breaking the weakening line.

[0034] The weakening elements 66, which are mainly located in the upper central region 44a, have an open-to-solid part length ratio of about 2: 1. In one embodiment, the open-to-solid part length in the upper central area 44a is 900: 400 (pm) and the ratio of the length of the open part to the solid part in the lower central region 44b is 450: 550 to 500: 500 (pm).

[0035] The weakening line may not necessarily be straight. In the sheath, the elements of weakness and the resulting line of weakness can be an oblique line, a curved line, or a line that changes direction, having for example angles, curves and / or inflections, including inflection points. In order to obtain the line of weakness in this type of embodiment, the material sheet will have to have elements of weakening using the appropriate model. In one embodiment, the weakening line begins at the tampon removable portion and slopes so that it ends at the central portion. Again, the weakening line may be inclined at an angle to the plane perpendicular to the longitudinal axis. The angle of inclination takes into account the need to keep the casing in one piece. The smaller the angle, the greater the force component applied to the packaging translates into a shear force that is able to break the weakening line. However, the small angle of inclination gives a greater possibility of tearing the sheath material between the ends of two separated lines of weakening so as to obtain packaging residue. The greater the angle of inclination, the smaller the possibility of tearing the sheath material between the ends of the weakening line so as to obtain two separated packaging residues.

[0036] In another embodiment, the weakening line starts at the bottom 5-25% of the sheet and ends at the insertion part. In yet another embodiment, the weakening line is not a straight line but a curved line that begins in the tampon removable portion, runs to the center portion, and ends in the removable portion. In these embodiments, a portion of the end of the removable casing is easily removed after breaking the line of weakness, which means that the insertion portion of the casing remains intact to some extent. This allows the user to manipulate the tampon without actually contacting or contaminating the end of the tampon being inserted.

[0037] In a preferred embodiment, the weakening line according to the present invention extends completely around the distal degree of the tampon circumference. As used herein, the term "extends completely around the circumference" means that the line of weakness draws a 360 ° angle around the circumference of the outer surface of the vaginal device.

[0038] When placed on the tampon, the sheath has a continuous weakness line that includes a two-layer seam. The line of weakness thus runs completely around the perimeter of the surrounded tampon. When used to wrap a tampon, the sheath has a weakness line 60 that may have one end near the end of the tampon being removed and the other end positioned toward the insertion end 14. In one embodiment, the weakening line is positioned and configured such that when the obtained casing is open, the tampon insert end portion remains on the tampon and the tampon removal end portion also remains on the tampon, but can be easily detached.

[0039] Overlapping and sealing of the margins does not affect the line of weakness, so that when the wearer opens the sheath, the weakening line is completely broken around and through the sealed cover. The seal does not prevent the weakening line from running through the application area to effectively guide the tear through the application area. If the weakening line is formed from a series of slots, forming a seam in the margins will not close the slots; instead, the gaps remain open enough to be easily torn apart.

[0040] After breaking the weakening line, the resulting open sheath can be removed as a uniform piece of material. Since the weakening line begins and ends at different parts of the seam, the weakening line will not divide the casing into separate pieces when it is opened. The end and beginning of the weakness line are far enough away so as not to overlap and to limit the likelihood of unwanted tear running between them. [0041] The seam not only connects the material layers to each other, but also provides a barrier that prevents contaminants from entering the packaged product. The seam can be any thickness depending on the materials being joined together and external conditions. For example, a sealed connection to protect against water may be thicker than a sealed connection used to prevent air leakage (for example, a tight connection used when wrapping dry food). In the present invention, the thickness of the sealed joint or seam is not critical.

[0042] The seam 70 may have any dimension that allows securely holding superimposed margins together. Although it is preferred that the edge 48 of the margin forming the outer surface is sealed to the bottom material, it is not necessary for the seam to run to the edge. As already mentioned, when sheet 40 is formed into a tube for holding a tampon, margins 52 and 54 overlap and are joined to form a double-layer seam 70. In one embodiment, sheet 40 is a single layer of material of such a type that when the margins 52 and 54 overlap, the two-layer seam has two layers. As the embodiment in Fig. 5 shows a single weakening line, the resulting wrapped material will have a single layer of weakened material. However, another embodiment may include additional short sections of weakness elements that can be aligned with and overlap to form one continuous weakness line 60 along with aligned weakened layers. See, for example, Fig. 11, together with the following discussion.

[0044] In the embodiment shown in Fig. 5, the second margin overlaps the first margin and partially forms the outer surface of the shell 100. The shell is essentially a tube-like cylinder. Both ends are closed so that the tampon inside the casing is completely contained inside the casing and separated from the environment. Seam 70 extends to edge 56 of margin 54 and creates a relatively smooth surface. The vaginal device in this figure has a longitudinal axis XX which extends through the insertion end 42 to the removal end 46 In Figure 5 a plane extending outward from and including the longitudinal axis XX is shown. The weakening line intersects this plane in at least three different places, circling a 360 ° angle around the perimeter of the tampon. These different places contain those where the plane intersects the two weakening elements at the margins of the casing and the weakening element located between these margins. Thanks to this, the plane crosses the weakening line in at least three different places - m ', m ", m"'.

[0045] The elongated seam is an elongated connection zone that joins together overlapping margins (52 and 54). According to the invention, the longitudinal connection zone is not a single, continuous seal line, but a plurality of seal lines that are discontinuous and offset relative to each other. This will be explained in more detail below.

[0046] In one embodiment of the invention (shown in Fig. 6), the seam 80 is at least one connection zone

78. The connection zone 78 has a gap 79 through which the weakening line 60 runs. This allows the weakening line to draw a 360 ° angle around the circumference.

[0047] Another embodiment is shown in Fig. 7.

Seam 81 includes a first connection zone 82 that has two slots, 83 and 85. The connection zone is substantially longitudinal and defines the sides of the seam. The weakening line runs through the gaps when the seam closes tightly and thus is not affected by sealing mechanisms such as a welding machine.

[0048] A third embodiment of the seal model is shown in Figure 8. In this embodiment, the connection zones 91 and 93 have slots 84 and 88, respectively, which are offset from each other and at different distances from the end of the sheath. Connection area 91 is located opposite connection area 93. If the weakening line has a first end positioned in the seam area at a distance from the end of the casing (one embodiment) and has a second end positioned at a second distance from the end of the casing, then the first and second slits must be so located that the line of weakness is in the two areas not sealed or occupied by gaps. As mentioned earlier, while in this example the gaps are of the type that alternate unsealed areas are obtained, it is also possible for the gaps to be aligned perpendicular to the longitudinal axis of the tampon when the finished tampon is completely sealed by the sheath. The most important is that the unsealed portion extends over the entire width of the seam so that the weakening line essentially runs around the perimeter of the tampon. In fig. 8 the weakening line may begin at one of the edges of the connection zone 91, run through the gap 88, further around the outer surface of the sheath, pass through the gap 84 and end at one of the edges of the connection zone 93. This figure shows edges 91a and 93a to illustrate one possible embodiment. The connection edges run into and contain the edges of the slots. In this embodiment, the weakening line 60 starts at edge 91a, runs through the gap 88 in the connection zone 93, runs around the product and through the gap 84 in the connection zone 91 and ends at the edge 93a. While some elements of the weakness line 60 run between the edge 48 of the sheath material and the edge 91 of the connection zone 91, they may or may not be effective as the weakening line because the connection zone 91 may adversely affect the ability of the weakening line 60 to actually significantly weaken the material of the sheath in this area. However, the line of weakness 60 can still run around the package, making an angle above 360 ​​° in this embodiment.

[0049] In another embodiment of the present invention (shown in Fig. 9), the seam 100 has three connection zones. While the seam shown generally extends in a longitudinal direction, other directions are also possible. Connection zones 120 and 160 have slots 130, 170 respectively. The connection zone 140 in this figure has two slots, 150 and 155, although it is possible to use one slot that is longer in the longitudinal direction and generally has an unsealed area that includes the slots 150 and 155. While the width of each connection zone is not particularly important , the seam must be strong. One way to achieve strength is to provide the entire surface of the welding machine with a similar configuration, suited to the sealed object. This increases the strength of the sealed joint during packaging and handling of the finished product.

[0050] The welding machine used to form the seal model shown in Fig. 9 is shown in Fig. 10. As shown in the drawing, the welder 150 has three sealing surfaces 122, 142 and 162 that form the connection zones 120, 140 and 160, respectively (shown in Fig. 9). Each sealing surface has at least two parts. For the sealing surface 122, an upper sealing surface 122b and a lower sealing surface 122a are used. The lower sealing surface 122a tightly closes the portion of the sheet that is in contact with the end of the tampon from the twine side, and the upper sealing surface 122b tightly closes the portion corresponding to the portion of the inserted tampon. For the sealing surface 142, an upper sealing surface 142b, a central sealing surface 142b and a lower sealing surface 142a are used. As already mentioned, the central sealing surface 142b can be omitted. For the sealing surface 162, an upper sealing surface 162b and a lower sealing surface 162a are used. The sealing surface 122 has a gap in the seal 124 which is between the upper and lower parts and corresponds to the gap in the connection 130. The sealing surface 162 has a gap in the seal 164 which is between the upper and lower parts and corresponds to the gap in the connection 170. As shown in the drawing, the slots in connection 155 and 170 are located at a similar distance from the end of the removed sheath. Similarly, the slots in combination 150 and 130 are also at a similar distance from the removed end.

[0051] In another embodiment of the welder shown in Fig. 11, the slots in seal 224 and 264 may include separate raised portions 200 that allow small, separate joints 202 to be obtained within larger slots in joint 230 and 270, as shown in Fig. 12. Such a small, separate connection may be in the form of dots, dashes or any other geometric pattern.

[0052] Another method for obtaining gaps in the seal (e.g., gaps 79 in Fig. 6; slots 83 and 85 in Fig. 7; slots 84 and 88 in Fig. 8; slots 130, 150, 155 and 170 in Fig. 9) provides for the use of a solid sealing element, as in the prior art solution (Fig. 3), on a casing material that is partially coated with a material that cannot be thermally bonded. For example, applying varnish to coat specific areas within the application area, and then exposing the application area to a continuous welder would result in a seam having a connection zone comprising the gap areas. Any material that cannot be thermally bonded can be used to prevent continuous seam formation. This material may be applied, for example, to the respective sides of the overlapping margins. An example of a weakness line 60 that has coatings 300, 300 'is shown in Figure 13. These coated areas are not bonded when margins 352, 354 overlap to form a seam.

[0053] Fig. 14 shows an alternative material sheet having a weakening line which can be formed to form a casing using the sealing model shown in Fig. 9. The sealing model formed by the welding machine shown in Fig. 10 would allow the weakening line to run inward seam without adversely affecting the perforations. In contrast to the embodiment shown in fig. 5 this material contains additional short sections (62, 64) of weakness elements that can be aligned with other weakness line elements and overlap to form one continuous weakness line 60 with aligned weakened layers.

[0054] In other embodiments, the seal model may be variants of the model described above. The lengths of the connection zones and the arrangement of the gaps in the connection can be changed to use multiple lines of weakness or a line of weakness with a steep slope. For example, the central connection zone (such as the connection zone 140 shown in Fig. 9) may be such that the gap 150 is closer to the insertion end than the removed end. Similarly, the gap 130 will be located at a similar distance as the gap 150. This alternating arrangement or displacement of the slots allows the weakening line to run inside the slots without becoming part of the sealed joint zone. The distance or arrangement of the gaps can be optimized depending on the angle of the weakening line, the material used or the thickness of the tampon being packaged.

[0055] The opening of the casing, which has the seal model described (Figs. 7, 8 and 9) to release the tampon along the weakening line (for example, as shown in Fig. 5), takes place in the initial tearing step, during which the casing 100 it is mainly torn under favorable, weakened angles, obliquely or in a slope around the perimeter of the tampon 10, and in the next stage during which the tampon is removed from the open casing 100. Opening the casing at an angle or obliquely results in a large open area, allowing you to easily remove the tampon with limited handling. The open cover remains in the form of a uniform element that ensures easy removal and disposal with one hand. Thereby the problem of adhering many small pieces of the casing to the fingers of the wearer or falling into the toilet is eliminated.

[0056] According to the present invention, it is basically that the distance between adjacent points is substantially equal along the entire weakening line. However, if necessary, varying gaps can be used to affect the tear force profile (increase / decrease in tear force as the tear spreads) experienced by the user when it opens the sheath along the line of weakness. A particularly preferred embodiment of the weakening line according to the present invention is the weakening line extending entirely around a portion of the wrapped tampon circumference, and in some embodiments the weakening line extends over a longer section than the wrapped tampon circumference. Absorbent materials useful for forming the absorbing body include fibers, foam, superabsorbent, hydrogels and the like. Preferred absorbent material for the present invention includes foam and fibers. Absorbing foams may include hydrophilic foams, foams that can be easily wetted by aqueous liquids, as well as foams in which the cell walls forming the foam themselves absorb the fluid.

[0058] Preferably, the fibers used to make the absorbent body comprise regenerated cellulose fibers, natural fibers and synthetic fibers. Preferably, the materials used to make the tampon of the present invention include fibers, foam, hydrogels, wood pulp, superabsorbents and the like. A preferred, non-limiting list of useful absorbent body fibers includes natural fibers such as cotton, wood pulp, jute and the like; processed fibers such as regenerated cellulose, nitrocellulose, acetyl cellulose, rayon, polyester, polyvinyl alcohol, polyolefin, polyamine, polyamide, polyacrylonitrile and the like. Other fibers than those mentioned above can be used to give the absorbing body additional desired properties. [0059] The tampon blank may be substantially surrounded or enclosed by a fluid-permeable coating. Thus, this coating surrounds most of the outer surface of the tampon. This can be accomplished, as disclosed in Friese, in US Patent No. 4,816,100, or Lochte; et al., US Patent Application No. US 2008/0064581 Al, entitled "Tampon Having Apertured Film Cover Thermobonded to Fibrous Absorbent Structure". In addition, the insertion end 14 of the tampon and the opposite end removed 18, or both, can be closed by the coating. Of course, due to processing or other reasons, some parts of the surface of the tampon 10 may be uncoated. For example, the insertion end 14 of the tampon 10 and a portion of the cylindrical surface adjacent this end may be exposed, uncoated to allow fluid to be more easily absorbed by the tampon 10.

[0060] The coating may be a nonwoven or perforated polymeric film. This coating may facilitate insertion of the tampon 10 into the body and may limit the possibility of separating the fibers from the tampon 10. Perforated polymer films useful in the manufacture of the coating are known to those skilled in the art.

[0061] Examples of casing materials suitable for use in the present invention include polymer films made of polyethylene, polypropylene, polyester, cellophane, polyamide, poly (vinyl chloride), ethylene / vinyl acetate copolymer and the like. Alternatively, heat shrinkable films, stretch films, pre-stretched flexible films and biodegradable materials can be used to produce the casing of the present invention. Preferred heat-shrinkable and stretch film compositions, although not limited to a given composition, contain mainly polyolefins, such as polyethylene and polypropylene, or poly (vinyl chloride). Polystyrene and polyethylene terephthalate (PET), although not heat-sealed, are also suitable for use in the present invention. In one embodiment of the present invention, the casing material is formed of a coextruded polypropylene film. Casings, consisting of these materials, can be closed by gluing using a binder. Other substantially occlusive materials include metal foils such as aluminum foil. While occlusive sheath materials are often preferred, non occlusive or porous materials such as nonwovens, fabrics, braids, meshes and papers can be used in other situations. Such non-occlusive materials can be converted to occlusive in joints, for example by lamination or coating with occlusive material. For cellulose papers, examples include laminating using a polymer film, such as a polyolefin composition, or coating or impregnating paper using wax. The above-mentioned materials can be coated with various chemical compounds to improve their barrier properties and sealing ability. Any suitable combination of the above-mentioned materials is also within the scope of the present invention. In some embodiments, materials suitable for use as casing materials in conjunction with the present invention can be heat-sealed to form the casing by closing the casing material by heat sealing after wrapping the tampon. In this way, a seam is produced in the areas of the casing that have been exposed to high temperatures. Alternative solutions for closing the casing material are gluing, stamping, bending, sewing, tangling, mechanical joining, cold pressing or ultrasonic welding. The seam may be a series of separate elements or it may be a continuous seal. In some embodiments, the sheath materials for use in the present invention have a low modulus of elasticity to provide a tampon sheath that generates low noise during transport as well as during handling, i.e., when opening the sheath.

[0062] The present invention also provides a method for packaging a tampon, which includes the steps of providing a casing blank comprising flexible sheet material of a certain width and length having at least one weakening line extending across substantially the entire width; forming the casing blank into a casing tube having a first and second end, with a length corresponding to the length of the casing blank and having an overlapping seam overlapping area having two layers of flexible sheet material; forming an elongated seam within the seam area by joining parts of two layers together while maintaining a specific model. The seam comprises a first, substantially longitudinal connection zone that defines a first side of the seam area, and a second, substantially longitudinal connection zone opposite to the first, substantially longitudinal connection zone that defines the second side of the seam area. The second substantially longitudinal connection zone has a gap formed therein near its first end corresponding to the first end of the sheath tube. The first substantially longitudinal connection zone has a gap formed therein near its first end corresponding to the first end of the sheath tube. The gap in the second substantially longitudinal connection zone is closer to the first end of the sheath tube than the gap in the first substantially longitudinal connection zone. The weakening line has a first end located in the seam area adjacent the first substantially longitudinal connection zone, extends through the slots in the second and first substantially longitudinal connection zone, and has a second end located in the seam area adjacent the second substantially longitudinal connection zone. The first end of the tube is then closed; the tampon is inserted into the tube and the other end of the tube closed.

24980 / ΡΕ / 15 EP 2 361 070