GB2203949A - Absorbent tampon - Google Patents

Abstract

An absorbent tampon, of generally cylindrical shape and capable of lateral expansion in use has a domed insertion end provided with a lubricant coating, to aid insertion, in the region of the shoulder intermediate the nose region of the dome end and the generally cylindrical side region of the tampon. One method of producing the coating in the desired region is to partially wrap the tampon, with the wrapping open at the dome end and applying a coating to the shoulder region, using the wrapping to inhibit coating of the tampon sides. Typical coating materials include high molecular weight polyurethane glycols.

Description

ABSORBENT TAMPONS The present invention relates to absorbent tampons and methods of manufacture.

Conventional absorbent tampons such as catamenial tampons normally comprise an absorbent material of general cylindrical shape, and can be formed from a length of absorbent material comprising hydrophilic fibres such as cellulosic fibres by compressing the material longitudinally or laterally or both. Tampons formed by lateral c.ompresFsion and in particular. -radial compression have the advantage of being capable of expanding laterally in use thereby inhibiting the leakage of menses around the inserted tampon. A typical method of forming radially compressed tampons is gisan. in British Patent N . 1082 7W0. The insertion end of conventional absorbent tampons normally has a rounded shape to facilitate the introduction of these tampons into the vagina.Such tampons, however, can be relatively painful to insert into the vagina because these tampons tend to absorb the mucus in the vagina tract thereby causing the tampons to have a relatively high frictional resistance on insertion which can lead to irritation of the membranes of the vaginal wall. It is therefore common to provide the insertion end of absorbent tampons with- a lubricant coating to reduce the frictional resistance of the tampon on insertion and thereby render the insertion less painful.

Lubricant coatings of the surface of a tampon however can prevent or inhibit the absorption of menses into the tampon. It would, therefore be advantageous to reduce the surface area of the tampon which is coated with lubricant while maintaining adequate lubrication.

British Patent No. 1 307 285 discloses an absorbent tampon which has a rounded insertion end portion #rovided with a l-ubrirant coating ove-r all the surface with the exception of the extreme nose end end so as to leave the front portion of the insertion end free of lubricant coating. An absorbent tampon, however, has now been found which has adequate lubrication properties in which th surface area#of the tampon coated with lubricant has been further reduced.

Accordingly the present invention provides an absorbent tampon having a rounded insertion end which is capable lateral expansion in use, which tampon has a rounded nose region, a generally cylindrical body .reg$on and an intermediate shoulder region and which is provided'with a lubricant coating to aid insertion of the tampon which is essentially only on the shoulder region.

The tampon of the invention thus has a reduced surface area of lubricant coating compared to that of prior art tampons thereby increasing the surface area of tampon available for absorbing menses. Furthermore it has been found that lubricant coating on the shoulder portion only of the tampon is sufficient to allow insertion of the tampon into the vagina without undue discomfort.

The lubricants used in the invention can be any of the lubricants which are suitable for coating absorbent tampons to reduce the frictional drag thereof during insertion into the vagina.

Prefe-rred lubricants for -use in the- invention comprise a water soluble polymer. Such a water soluble polymer lubricant coating on a tampon of the invention in use can, on contact with the vagina wall, absorbed moisture and become highly lubricous thus further enhancing the lubricant nature of the coating.

Furthermore a water soluble polymer lubricant coating on a tampon after insertion may eventually be dissolved by fluids present in the vagina from the surface of the tampon thereby making the surface available for absorbing menses.

Suitable water soluble polymers for use as a lubricant coating in the invention include polyethylene glycols. Suitable polyethylene glycols have an average molecular weight of from 100 to 10,000. Typically the lubricant average molecu#lare weight will exceed 250 coating may comprise one or a mixture of two or more such polyethylene glycols. Polyethylene glycols of the hereinabove mentioned molecular weight can range from liquids to waxes. Favoured polyethylene glycols for use as lubricant coatings n the~ invention -have-- -an average molecular weight of 1000 to 6000 preferably about 4000.Such favoured polyethylene glycols are waxes at ambient room temperature and therefore lubricant coatings of these polyethylene glycols will tend to stay on the surface of the tampon and not-~be absorbed thereby prior to use. Furthermore these polyethylene glycols tend to melt or soften at body temperatures which may enhance the lubricant properties of lubricant coatings of these polymers on tampons of the invention during insertion thereof into the vagina.

An apt polyethylene glycol for use in the invention is known as PEG 4000 which has an average molecular weight of approximately 4000.

Favoured polyethylene glycols which are waxes at ambient room temperature can contain a plasticiser such as glycerol to render the lubricant coating flexible.

The amount of glycerol present in the polyethylene glycol can suitably be 1 to 5% by weight and can pte#ferably be 2 to 7% by weight for example -5% by weight.

Mixtures of polyethylene glycols may be employed, which mixtures can contain one or more polyethylene glycols having an average molecular weight of from 4000 -to 6000, forexample PEG 4000 and one or more polyethylene glycols which are normally liquid at room temperature. Such normally liquid polyethylene glycols may have an average molecular weight of from 100 to about 400 and may typically be about 200. Mixtures of higher and lower molecular weight polyethylene glycols may be p7asti-cised with, for example, glycerol, as- described aforesaid.

The weight per unit area of the lubricant coating on the tampon is preferably sufficient to provide a smooth coating. The weig#ht per unit area of lubricant coating on the tampon can suitably be from 0.01 to 0.25g/cm2 and can preferably be less than 0.lg/cm2 more preferably about 0.025g/cm2 Apt tampons of the invention have a lubricant coating on the shoulder portion of the rounded insertion end thereof which comprises PEG 4000 containing 5% by weight of glycerol and which has weight per unit area of 0.1/cm . An apt tampon of this type which has a hemispherical rounded insertion end of approximately 1 scum -d-iameter,- has lubricant coating weight of 0.1 to 0.8g.

The absorbent tampon used in the invention can be any of the absorbent tampons conventionally used for catamenial purposes whist hays a rounded insertion end and is capable of expanding laterally in use.

Suitable methods of forming a rounded end on a absorbent include those disclosed in British Patent No.

1046066. The rounded insertion end can be hemispherical, conical or alike tapered shape.

favoured tampons of the invention-compri-se a #-spirally -wound fleece of absorbent cellulosic fibres which has been compressed radially for example between compression dies.

Suitable methods of making tampons comprising spirally wound fleece include those disclosed in British Patent No. 1098400. Suitable methods of forming tampons by radially compressing absorbent material include those disclosed in British Patent 1082770.

The absorbent tampons of the invention will be suitable for digital use. The tampons can be packed within a wrapper of water impermeable film such as moisture proof coated cellulose film, polypropylene film or--po-lyethy-lene filme The film -can -conventionally be closed by a breakable seal for example a heat seal over insertion end to enable the tampon to be inserted via the seal from the wrapper into the vagina.

Suitable wrappers of this type are disclosed in British ~Patent No. 1305472.

The tampon within the wrapper can favourably be sterile. Suitable methods of sterilising include gamma and electron beam irradiation methods.

In another aspect the invention provides a method of forming a tampon of the invention which comprises providing a lubricant coating on the rounded insertion end of an absorbent tampon of general cylindrical shape, which is capable of lateral expansion in use, which insertion end has a front portion and an shoulder portion which is adjacent to the side surface of the tampon wherein the lubricant coating is provided at the insertion end is limited to the shoulder portion thereof.

The materials used in the method of the invention can be the materials described hereinbefore in relation to the tampon of the invention.

In the method of the invention lubricant coating can be provided on the tampon by any suitable method.

Suitable methods include adhering a preformed solid film of the lubricant to the tampon by for example solvent or heat and coating the lubricant in liquid form for example as a hot melt or as a solution onto the tampon by spraying or other coating method. A favoured method of the invention comprises spraying the lubricant as a hot melt onto the shoulder area of the tampon. favoured polyethylene glycols of the invention can be sprayed as a hot melt at a temperature of 60 to 70 C.

In a method of the invention which comprises spraying##the lubricant can be sprayed as a band on the shoulder portion of the insertion of the tampon by controlling the width of the spray and rotating the spray head or the tampon under the spray head. In such methods the surface of the main body of the tampon which is adjacent to the shoulder portion can advantageously be surrounded by a cylindrical member to inhibit the lubricant being coated on the side surface of the tampon. The cylindrical member can favourably be part of the outer wrap of the tampon before it is sealed. The invention will now be illustrated with reference to the following drawings in which Fig. 1 is a longitudinal cross section of a tampon of the invention.

-fig . 2 is a schematic drawing shown in cross .se-ction nf a preferred method of forming the tampon of Fig.

1.

Fig. 1 shows an absorbent tampon 1 of general cylindrical shape which is capable of lateral expansion in use. The tampon has a rounded insertion end 2 which is provided with a lubricant coating 3. Insertion end 2 has a front or nose portion 4 and a shoulder portion 5 which is adjacent to the side surface 6 of tampon 1. Lubricant coating 3 of tampon 1 shown in Fig. 1 is limited to the shoulder portion 5 so that front portion 4 and side surface 6 adjacent to shoulder portion 5 are free of lubricant coating.

Fig. 2 shows a method of coating tampon 1 of fig. 1 in which the lubricant is being coated for example as a hot melt from a spray head 7 onto the shoulder portion 5-of -tampon 1, Fig. 2 shows surface 6 of tampon 1 is surrounded by a cylindrical member 8 which can conveniently be the part of the tampon wrapper to prevent the coating being deposited on the tampon side surface 6. In the method tampon 1 can be rotated around the axis A - A to provide the lubricant coating 3 on the shoulder portion 5 as a band.

The lubricant coated tampon so formed can then be sealed in its wrapper optionally rendered sterile within the wrapper ready for use as an absorbent tampon of the- invention.

The tampon can then be insertedo digitally into a vagina from the wrapper. It has been found that the lubricant coating on the shoulder portion only of the insertion end of the tampon is sufficient to render the tampon insertable in a vagina without undue discomfort.

Claims (10)

1. An absorbent tampon having a rounded insertion end and which is capable of lateral expansion in use, which tampon or nose region, a generally cylindrical body and a shoulder region intermediate the-nose region and the body which is provided with a lubricant coating to aid insertion of the tampon wherein the lubricant coating on the insertion end is limited to the shoulder portion thereof.

2. A tampon as claimed in claim 1 in which the lubricant coating comprises a water soluble polymer.

3. A tampon as claimed in claim 2 in which the water soluble polymer is a polyethylene glycol having an average molecular weight of 100 to 10 000-.

4. A tampon as claimed in claim 3 in which the polyethylene glycol has average molecular weight of 1000 to 6000.

5. A tampon as claimed in claim 3 or claim 4 in which the polyethylene glycol contains a plasticiser.

6. A tampon as claimed in claim 5 in which the plasticiser is glycerol and is present in the polyethylene glycol in an amount which is 2 to 7% by weight.

A A tampon as claimed in any of claims i--to -6 in which the weight per unit area of the lubricant coating on the insertion end of the tampon is 0.01 to 0.25 9/cam2 .

8. A tampon as claimed in any of claims 1 to 7 which is sterile within a wrapper.

9. A method of producing a tampon having a rounded insertion end and a lubricant coating thereon, wherein said tampon is an absorbent tampon which is capable of la-t-eral expansion in use and comprises a generally cylindrical body region, a nose region and intermediate shoulder and wherein said coating is applied essentially to the shoulder.

10. A method as claimed in claim 9 which comprises spraying the lubricant as a hot melt onto the shoulder portion of the rounded insertion end of the tampon.