阅读说明：本技术 成形用于女性卫生的棉塞的方法 (Method of forming a tampon for feminine hygiene ) 是由 K·A·佩利 于 2015-11-11 设计创作，主要内容包括：本发明提供了一种形成成形的尺寸上稳定的棉塞的过程,该过程包括如下步骤：径向压缩棉塞坯料,以形成具有脱脂棉中间体直径和纵向轴线的尺寸上稳定的脱脂棉中间体；将脱脂棉中间体置于中空载体中,并且将脱脂棉中间体和中空载体插入模具中；经由支撑在容纳在中空载体内的脱脂棉中间体的端部上的冲头来促使脱脂棉中间体进入模具中,并且从模具抽出中空载体,以允许脱脂棉中间体的暴露端基本上填充模具并形成成形的尺寸上稳定的棉塞；从模具取出成形的尺寸上稳定的棉塞；以及将成形的尺寸上稳定的棉塞封装在适形于该棉塞的形状的初级包装件中。模具具有进入开口,中空载体可通过该进入开口抽出。(The present invention provides a process for forming a shaped, dimensionally stable tampon comprising the steps of: radially compressing the tampon blank to form a dimensionally stable intermediate pledget having an intermediate pledget diameter and a longitudinal axis; placing the intermediate absorbent cotton in a hollow carrier, and inserting the intermediate absorbent cotton and the hollow carrier into a mold; urging the intermediate pledget into the mold via a punch supported on an end of the intermediate pledget contained within the hollow carrier and withdrawing the hollow carrier from the mold to allow the exposed end of the intermediate pledget to substantially fill the mold and form a shaped, dimensionally stable tampon; removing the formed dimensionally stable tampon from the mold; and enclosing the shaped dimensionally stable tampon in a primary package that conforms to the shape of the tampon. The mould has an access opening through which the hollow carrier can be withdrawn.)

1. A method of forming a shaped, dimensionally stable tampon comprising the steps of:

a. radially compressing the tampon blank to form a dimensionally stable intermediate pledget having an intermediate pledget diameter and a longitudinal axis;

b. placing the absorbent cotton intermediate in a hollow carrier;

c. inserting the intermediate pledget and the hollow carrier into a mold having a shape corresponding to a desired final tampon shape, wherein the desired final tampon shape has a maximum dimension perpendicular to the longitudinal axis that is greater than a maximum diameter of the intermediate pledget, wherein the mold has an access opening through which the hollow carrier can be withdrawn and an enlarged portion;

d. urging the intermediate pledget into the mold via a punch supported on an end of the intermediate pledget received in the intermediate hollow body and withdrawing the hollow carrier from the mold such that an exposed end of the intermediate pledget is forced against the mold, whereby an axial force on the intermediate pledget provides a radial expansion from the longitudinal axis of the intermediate pledget to allow the exposed end of the intermediate pledget to fill the mold and form the shaped dimensionally stable tampon;

e. removing the formed dimensionally stable tampon from the mold; and

f. enclosing the shaped dimensionally stable tampon in a primary package that conforms to the shape of the tampon.

2. The method of claim 1, wherein the mold is a split cavity mold.

3. The method of claim 1, wherein the enlarged portion of the mold has a circular cross-section perpendicular to the longitudinal axis of the cotton wool intermediate.

4. The method of claim 1, wherein the enlarged portion of the mold has an oval cross-section perpendicular to the longitudinal axis of the cotton wool intermediate.

5. The method of claim 1 wherein the enlarged portion of the mold corresponds to an insertion end of the tampon.

6. The method of claim 1 wherein the enlarged portion of the mold corresponds to a central portion of the tampon.

7. The method of claim 1, wherein the enlarged portion of the mold comprises a plurality of enlarged areas.

8. The method of claim 7, wherein one expanded area is disposed at a first end of the mold cavity corresponding to an insertion end of the tampon and another expanded area is disposed at a second end of the mold cavity corresponding to a withdrawal end of the tampon.

Technical Field

The present invention relates to a method for forming a fibrous tampon having a non-cylindrical shape.

Background

Individual absorbent articles for personal hygiene articles are protected from environmental contamination by sheets of material commonly referred to as wrappers or overwraps. In particular, tampons employ a wrapper in which each tampon is contained in a separate primary wrapper, and a large number of such primary wrappers may then be packaged in a secondary wrapper (typically a box) for sale. Tampons are generally divided into two types: applicator tampons and digital tampons. Applicator tampons are basically tampons contained within an applicator. The applicator may be plastic or cardboard and may include design elements, such as finger grips or petals for ease of insertion.

The wrapper of an applicator tampon is typically elongated loose and the flanges or fins are sealed at the ends with a small cut or notch at one end that the user can use to tear the wrapper in a longitudinal manner.

Digital tampons are basically compressed cylindrical objects and may include a tapered insertion end. Because digital tampons are not contained within the applicator, they are typically contained within a wrapper. The wrapper of a digital tampon is typically a tight fit, typically contacting the outer surface of the tampon completely around the perimeter, and sealing against the tampon at the insertion and withdrawal ends. Such tight packing may help maintain the shape of the tampon and prevent deformation.

Previously, the wrapper has been made of a light-transmitting type material such as plastic (e.g., polypropylene) or cellophane. Since digital tampons also typically contain a cover over the absorbent material, it is sometimes necessary to include a slip agent or antistatic agent to ensure that the tampon is easily removed from the wrapper and that portions of the wrapper do not adhere to the tampon during insertion.

The packaging of digital tampons has presented a number of problems over the years. Sometimes the tampon "relaxes" after compression and is difficult to remove from the wrapper due to the tight fit. Some wrapper materials actually stick to the outer surface of the tampon and make it difficult to remove the tampon due to material interaction, resulting in the user prying the overwrap from the tampon. See, for example, WO 2004/080362. Other times, depending on the wrapper material selected, there may be an electrostatic charge between the tampon and the wrapper, resulting in the wrapper sheet adhering to the user's fingers after the wrapper is broken to seal and remove the tampon.

New improvements to digital tampons include shaping the body of the tampon, changing the grooves, and providing surface aberrations such as ridges or depressions. The process of making these types of shaped or patterned tampons typically involves a split mold cavity, which allows the tampon to be removed from the mold without disrupting the shape or surface of the tampon. Providing a wrapper to ensure cleaning can be challenging for shaped tampons to be inserted by a finger. Shaped tampons may require a non-cylindrical package to maintain their shape.

The present invention proposes a solution to form a shaped tampon and to provide a wrapper that provides cleanliness and helps maintain the shape of the tampon during storage.

Disclosure of Invention

Surprisingly, we have found a new method of providing a shaped dimensionally stable tampon in which the desired final tampon shape has a maximum dimension perpendicular to the longitudinal axis that is greater than the maximum diameter of the pledget intermediate. In one aspect of the invention, the process of forming a shaped, dimensionally stable tampon comprises the steps of: radially compressing the tampon blank to form a dimensionally stable intermediate pledget having an intermediate pledget diameter and a longitudinal axis; forming a shaped primary tampon package having a length, a first closed end, and a second open end; inserting a pledget intermediate into a shaped primary tampon package, a first portion of the pledget intermediate adjacent a first enlarged portion of the shaped primary tampon package and a second portion of the pledget intermediate adjacent a second portion of the shaped primary tampon package; expanding a first portion of the intermediate pledget to substantially fill a first enlarged portion of a shaped primary tampon package to form a dimensionally stable tampon; and closing the second open end of the formed primary tampon package.

In another aspect of the invention, the process of forming a shaped, dimensionally stable tampon comprises the steps of: radially compressing the tampon blank to form a dimensionally stable intermediate pledget having an intermediate pledget diameter and a longitudinal axis; placing the intermediate absorbent cotton in a hollow carrier, and inserting the intermediate absorbent cotton and the hollow carrier into a mold; urging the intermediate pledget into the mold via a punch supported on an end of the intermediate pledget received within the hollow carrier and withdrawing the hollow carrier from the mold such that the exposed end of the intermediate pledget is forced against the mold, whereby an axial force on the intermediate pledget provides a radial expansion from the longitudinal axis of the intermediate pledget to allow the exposed end of the intermediate pledget to substantially fill the mold and form a shaped, dimensionally stable tampon; removing the formed dimensionally stable tampon from the mold; and enclosing the shaped dimensionally stable tampon in a primary package that conforms to the shape of the tampon. The mould has an access opening through which the hollow carrier can be withdrawn.

Drawings

Fig. 1 is a perspective view of a tampon according to the prior art.

FIG. 2 is a perspective view of a tampon according to the present invention.

Fig. 3 is a perspective view of a cotton wool intermediate according to an embodiment of the present invention.

FIG. 4 is a side view of a primary tampon package according to one embodiment of the present invention.

FIG. 5A is a side view of a primary tampon package intermediate disposed on a forming mandrel prior to formation.

FIG. 5B is a cross-section of a primary tampon package intermediate disposed on the forming mandrel of FIG. 5A.

FIG. 6A is a side view of a primary tampon package intermediate on a forming mandrel in a package forming mold (cross section).

FIG. 6B is a side view of the primary tampon package intermediate of FIG. 6A deployed onto a forming mandrel in a package forming mold (cross-section).

FIG. 7 is a side view of the primary tampon package of the embodiment of FIGS. 5-6.

Fig. 8 is a side view of the assembly of the primary tampon package, the intermediate pledget, the hollow mandrel carrier, and the punch prior to placing the assembly in the tampon forming die.

FIG. 9 represents a step of the process of the present invention and is a side view of the assembly of FIG. 8 in a tampon forming mold (cross section) with axial force applied to the base of the tampon.

Fig. 10 shows steps of the process of the present invention and is a side view of the assembly of fig. 8-9 and a formed dimensionally stable tampon formed in a tampon forming mold (cross-section).

FIG. 11 is a side view of a formed dimensionally stable tampon formed in a primary tampon package prior to closing the remaining open end thereof.

Fig. 12 is a side view of the final packaged shaped product of fig. 5-11.

Fig. 13 represents a step in an alternative process and is a side view of the assembly of the intermediate pledget, hollow mandrel carrier, and punch in a tampon forming die (cross-section) and axial force applied to the base of the tampon.

FIG. 14 shows a step in the process of FIG. 13 and is a side view of the assembly of FIG. 13 and a formed dimensionally stable tampon formed in a tampon forming mold (cross-section).

Fig. 15A-C are side illustrations of alternative tampon shapes.

FIG. 16A is a top plan view of an alternative tampon shape.

FIG. 16B is a side elevational view of the tampon of FIG. 16A.

FIG. 16C is an end view of the tampon of FIGS. 16A-B showing the oval cross-section of the enlarged portion.

FIG. 17A is a top plan view of an alternative tampon shape.

FIG. 17B is a side elevational view of the tampon of FIG. 17A.

FIG. 17C is an end view of the tampon of FIGS. 17A-B showing the oval cross-section of the enlarged portion.

Detailed Description

A more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof that are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.

Referring to fig. 1, a radially compressed tampon 10 for feminine hygiene according to the prior art is a substantially cylindrical body 20 of compressed fibers having an insertion end 30 and a withdrawal end 40 with a withdrawal string 50 extending therefrom. Such tampons have sufficient dimensional stability to allow insertion into the vagina of a user to absorb menses without the need for an additional applicator. These tampons are often described as digital tampons and can be inserted by finger (by using one's finger, without an applicator). Typically, these tampons comprise a liquid permeable outer cover 60 and are compressed in a manner that creates a plurality of substantially longitudinally extending grooves 70 separated by ribs 80. The grooves may be aligned parallel to the central longitudinal axis, as described in Friese et al, U.S. patent 6,310,269, spirally oriented about the outer surface, as described in schoeling, U.S. patent 8,735,647, or otherwise oriented along the length of the product, such as described in the following patents: U.S. Pat. Nos. 8,460,262B 2 to Fung et al; U.S. Pat. Nos. 8,827,975B 2 and 8,834,439B 2 to Kimball et al; and european patent 1459720B 1 to Hysalma GmbH.

We have found that it is possible to convert such prior art tampons into shaped tampons for distribution and sale to consumers. In particular, we have developed a method of forming a tampon 100 for feminine hygiene into a structure having an enlarged portion 110 at one end thereof. Such a tampon 100 according to the present invention is shown in fig. 2. The tampon has a body 120 of compressed fibers having an insertion end 130 and a withdrawal end 140 having a withdrawal string 150 extending therefrom. Also, the tampon pledget has sufficient dimensional stability to allow insertion into the user's vagina by a finger. Such tampons are formed by the following process. In general terms, a tampon is pressed axially into a split-cavity mold while at least a portion of the tampon is maintained within the interior of the hollow mandrel. Thus, as shown in FIG. 2, the tampon 100 has an enlarged insertion portion 110. In a preferred embodiment, the tampon 100 also has a cover 160, longitudinal grooves 170, and longitudinal ribs 180.

The tampon of fig. 2 can be manufactured according to our new process. First, having a diameter D of an intermediate absorbent cotton_IA conventional radially compressed dimensionally stable substantially cylindrical pledget intermediate 190 (as shown in fig. 3) can be made according to one or more of the following patents: friese et al, U.S. patent 6,310,269, oriented helically around the outer surface, as described in schoeling, U.S. patent 8,735,647, or otherwise oriented along the length of the product, such as described in the following patents: U.S. Pat. Nos. 8,460,262B 2 to Fung et al; U.S. Pat. Nos. 8,827,975B 2 and 8,834,439B 2 to Kimball et al; and european patent 1459720B 1 to Hysalma GmbH, the disclosure of which is incorporated herein by reference. Generally, a pledget intermediate is formed by first obtaining a shaped mass of absorbent material known as a tampon blank. The web may be in the form of a roll of sheet material, a continuous length of absorbent material, a random or substantially uniformly oriented mass of absorbent material, a separately prepared or molded mass of absorbent material, or the like. The tampon blank is relatively uncompressed and has a relatively low density. And then compressed to form an intermediate body of absorbent cotton having an overall size smaller than that of the blank before use. The intermediate pledget 190 is then further processed to provide the enlarged portion 110 shown in fig. 2.

In one embodiment of the process, a primary tampon package 200 is formed having a length, a first closed end 210, and a second open end 220 (FIG. 4), the length being substantially greater than a dimension perpendicular thereto and defining a longitudinal axis X-X. The primary tampon package 200 has a first portion 230 extending from the first closed end and a second portion 240. The ends may be closed as known to those of ordinary skill in the art. For example, a folded seal, such as four, or six or more folds around the end. More folds may better conform to the cylindrical shape. Furthermore, a curved flange seal may also be used. The second portion 240 of the primary tampon package 200 is of substantially uniform diameter D_POf substantially cylindrical shape, the diameter D_PIs larger than the diameter D of the absorbent cotton intermediate 190_IAnd the first portion 230 is enlarged relative to the second portion 240 along at least one dimension perpendicular to the longitudinal axis X-X.

In one embodiment, the primary tampon package 200 may be formed by wrapping a sheet of plastic wrapping around a cylindrical mandrel and sealing the sheet to form a cylindrical tube. One end of the tube is closed and sealed so as to produce a cylindrical elongated intermediate primary tampon package having one open end. As shown in fig. 5A and 5B, the intermediate primary tampon package 250 having a closed end 260 is then placed onto a second hollow forming mandrel 270 having a formed end 280. The hollow forming mandrel 270 has a reduced diameter (compared to most forming mandrels) and air bleed 282, air bleed and air return 284 at the forming end 280 to allow air circulation, as described below. As shown in FIG. 6A, the primary tampon package intermediate 250 and hollow forming mandrel 270 are placed in a mold 290 in a hot air thermoformer that is closed by a clamp 292 to isolate the forming chamber 294. Hot air is delivered through the conduit 272 in the interior of the hollow forming mandrel 270 to the air bleed 282 (as indicated by arrow 286) inside the primary tampon package central body 250, through the gap between the forming ends 280 of the mandrel, and is drawn through the air return 284 and the annular ring 274 of the hollow forming mandrel 270 (as indicated by arrow 288) to soften the plastic material. As shown in FIG. 6B, the airflow from the annular ring 274 is blocked (e.g., via the plug 276) to pressurize the interior of the primary tampon package 250 to expand the closed end 260 of the package into the form of the mold 290. This results in an enlarged first portion 230 of the primary tampon package 200 near its first end 210, as shown in fig. 4 and 7.

To form the tampon pledget intermediate 190 into a desired dimensionally stable feminine hygiene tampon, an apparatus having a split cavity mold 300 substantially corresponding to the shape of the primary tampon package 200 is used. A substantially cylindrical tampon pledget intermediate 190 is placed in the hollow mandrel carrier 310 and the formed primary tampon package 200 is placed over the carrier/tampon pledget intermediate 310/190 as shown in fig. 8. The resulting assembly is placed in a split cavity mold 300 and the punch 320 is aligned with the tampon pledget intermediate 190 along the longitudinal axis X-X of the primary tampon package 200. The split cavity mold 300 is closed (either before or after the assembly is inserted therein) and a tampon forming process is performed. As shown in fig. 9, the hollow mandrel carrier 310 is withdrawn from around the tampon pledget intermediate 190 to expose an increased amount of the ends 330 of the pledget 190 in the enlarged portion 340 of the split-cavity mold 300. As the hollow mandrel carrier 310 is withdrawn, the punch 320 applies a force along the longitudinal axis X-X to force the exposed end 330 of the tampon pledget intermediate 190 against the split cavity mold 300. This axial force (represented by arrow 350) translates into a radial expansion (represented by arrow 360) of the exposed end 330 of the tampon pledget intermediate 190 to fill the enlarged volume 340 of the split-cavity mold 300 and the primary tampon package 200. As the hollow mandrel carrier 310 continues to be withdrawn from the split-cavity mold 300 and the punch 320 continues to force the tampon pledget intermediate 190 against the split-cavity mold 300, the fibrous structure completes its expansion into the enlarged portion 330 of the split-cavity mold 300 and the primary tampon package 200 (as shown in fig. 10). Once the hollow mandrel carrier 310 has moved out of the enlarged portion 330 of the split-cavity mold 300 and the fibrous structure has filled the enlarged portion of the mold 330, the punch 320 stops its travel into the mold 300.

The hollow mandrel carrier 310 may be fully withdrawn from within the primary tampon package 200 and the split cavity mold 300 may be opened to allow the shaped tampon 100 to be removed therefrom. Of course, the hollow mandrel carrier 310 may be left around the unexpanded portion of the tampon 100 to facilitate its removal from the mold 300. The open end 220 of the primary package 200 may then be closed (as shown in fig. 11) to provide a final packaged shaped tampon product 1000 (as shown in fig. 12). The ends may also be closed as known to those of ordinary skill in the art. For example a folded seal as described above, a flange seal (optionally with a notch to enable propagation of the tear to open the package). Alternatively, the primary tampon package may include a reinforced tear strip.

In another embodiment of our process (shown in fig. 13 and 14), a split cavity mold 300' having a shape substantially corresponding to the desired finished tampon is used. As with the previous embodiment, a substantially cylindrical tampon pledget intermediate 190 is disposed in a hollow mandrel carrier 310. However, only the hollow mandrel carrier 310 and the substantially cylindrical tampon pledget intermediate 190 form an assembly that is placed in the split cavity mold 300', and the punch 320 is aligned with the tampon pledget intermediate 190 along the longitudinal axis X-X of the tampon pledget intermediate 190. The split cavity mold 300' is closed (either before or after the assembly is inserted therein) and a tampon forming process is performed. The hollow mandrel carrier 310 is withdrawn from around the tampon pledget intermediate 190 to expose an increased amount of pledget ends 330 in the enlarged portion 340 'of the split-cavity mold 300'. As the hollow mandrel carrier 310 is withdrawn, the punch 320 applies a force along the longitudinal axis X ' -X ' to force the exposed end 330 of the tampon pledget intermediate 190 against the split cavity mold 300 '. This axial force (represented by arrow 350) translates into a radial expansion (represented by arrow 360) of the exposed end 330 of the tampon pledget intermediate 190 to fill the enlarged volume 340 'of the split-cavity mold 300'. Once the hollow mandrel carrier 310 has moved out of the enlarged portion 340 ' of the split-cavity mold 300 ' and the fibrous structure has filled the enlarged portion 340 ' of the mold 300 ', the punch 320 stops its travel into the mold 300 '. The hollow mandrel carrier 310 may be fully withdrawn from the split cavity mold 300', which may be opened to allow the shaped tampon 100 to be removed therefrom. Of course, the hollow mandrel carrier 310 may be left around the undeployed portion of the tampon 100 to facilitate removal from the mold 300'. The formed tampon 100 may then be enclosed within a primary tampon package, which may have been previously formed to contain the finished tampon, or it may be formed around the finished tampon, for example, by shrink wrapping (as shown in FIG. 12 for the previous embodiment).

While the tampons have been described above with respect to tampons having an enlarged end, particularly an enlarged insertion end, alternative embodiments are also contemplated, including a tampon 400 having two enlarged ends 410,420, and a withdrawal string 450 (fig. 15A); a tampon 500 (fig. 15B) having two compressed ends 510,520, an enlarged central portion 530, and a withdrawal string 550; and a tampon 600 (fig. 15C) having a compressed insertion end 610, and a deployed withdrawal end 620, and a withdrawal string 650, among others. These embodiments would require an improved split cavity mold that provides the desired shape. Further, the embodiment of fig. 15C may require a second punch having a cross-sectional dimension corresponding to the dimension of the withdrawal end.

Further, the cross-section of the finished tampon may be cylindrical or other desired shape. For example, FIG. 16 shows a tampon 700 having a different cross-sectional shape. The compressed portion 710 of the finished tampon 700 may be substantially cylindrical in cross-section, while the expanded portion 720 may be more oval-like in cross-section, as shown in fig. 16A-C. In an alternative embodiment, FIG. 17 shows a tampon 800 having a different cross-sectional shape. The cross-section of the compressed portion 810 of the finished tampon 800 may taper from cylindrical to elliptical, while the cross-section of the enlarged portion 820 may be more elliptical, as shown in fig. 17A-C.

As the tampon is formed by pressing the pledget intermediate, it is pressed axially into the split-cavity mold while at least a portion of the tampon remains within the interior of the hollow mandrel. This results in radial expansion into the split cavity mold, as described above. The intermediate absorbent cotton is longer than the finished tampon. In one embodiment, the length of the finished tampon is between about 80% and about 95% of the length of the intermediate pledget from which it is formed. Preferably, in this embodiment, the length of the finished tampon is between about 90% of the length of the intermediate pledget from which it is formed.

Depending on the volume of the cavity of the split cavity mold and the axial force on the pledget intermediate, the fiber density of the finished tampon can be substantially similar to the fiber density of the pledget intermediate from which it is formed, or it can be different from that fiber density. One of ordinary skill in the art will know to adjust the force and volume to achieve the desired fiber density in the enlarged portion of the finished tampon. As used in the specification and claims, the term "fiber density" and variations thereof relate to the relative proportion of fibers to void volume in a given volume of fibrous structure.

In a preferred embodiment, the split cavity mold used to form the shaped tampon from the pledget intermediate operates at ambient conditions. In an alternative embodiment, depending on the materials used in the process, the addition of sufficient heat may be beneficial to fix the fibers in the expanded shape.