Sanitary article comprising a water-soluble dry coating comprising skin beneficial additives

Abstract

A sanitary article, such as a sanitary pad, a pantyliner, a pant diaper or an open diaper, according to the present disclosure includes a fluid permeable topsheet and a backsheet. The sanitary article extends in a longitudinal direction and a transverse direction and has first and second longitudinal side edges and a front and a rear edge. The topsheet is provided with a dry coating in a coated zone on a first side thereof, the first side of the topsheet being the wearer facing side of the topsheet, the dry coating is a water-soluble dry coating comprising allantoin and betaine.

Claims

1. A sanitary article comprising a fluid permeable topsheet and a backsheet, the sanitary article extending in a longitudinal direction and a transverse direction and having first and second longitudinal side edges and a front and a rear edge, the topsheet being provided with a dry coating in a coated zone on a first side of the topsheet, the first side of the topsheet being the wearer facing side of the topsheet, wherein the dry coating is a water-soluble dry coating comprising allantoin and betaine, wherein the allantoin is present in the dry coating in amount within the range of from 0.0002 to 0.36 gsm, and wherein the betaine is present in the dry coating in amount within the range of from 0.001 to 1.2 gsm.

2. The sanitary article according to claim 1, wherein the sanitary article is a pantyliner or a sanitary pad and the dry coating covers at least 25% of a total surface area of the topsheet.

3. The sanitary article according to claim 1, wherein the sanitary article is an open diaper, a belt diaper or a pant diaper and the dry coating covers at least 2% of a total surface area of the topsheet.

4. The sanitary article according to claim 1, wherein the dry coating is applied within the dry coated zone in an amount with the range of from 0.2 gsm to 12 gsm.

5. The sanitary article according to claim 1, wherein the topsheet comprises a second side being an opposition side to the first side, the second side of the topsheet being printed in a printed zone and wherein coated zone on the first side of the topsheet partly or completely overlaps with the printed zone, as seen in a depth direction perpendicular to the longitudinal direction.

6. The sanitary article according to claim 1, wherein the dry coating comprises glycerine, propylene glycol and/or PEG.

7. The sanitary article according to claim 6, wherein the absorbent core comprises pulp fibers and/or superabsorbent polymer particles.

8. The sanitary article according to claim 1, wherein the sanitary article comprises an absorbent core.

9. The sanitary article according to claim 1, wherein the coated zone is arranged along the rear edge and the first and the second longitudinal side edges in a rear third of the sanitary article and forming a boundary in the rear third delimiting an inner rear zone comprising or consisting of a coating free topsheet area, the inner rear zone extending along the longitudinal centreline, optionally the coated zone covers at least 25% of the total surface area of the topsheet in the rear third of the article.

10. The sanitary article according to claim 1, wherein the coated zone is arranged along the front edge and the first and the second longitudinal side edges in a front third of the sanitary article, the coated zone delimiting an inner front zone comprising or consisting of a coating free topsheet area, the inner front zone extending along the longitudinal centreline, optionally the coated zone covers at least 25% of the total surface area of the topsheet in the front third of the article.

11. The sanitary article according to claim 1, wherein the coated zone forms a boundary in the central third of the sanitary article delimiting an inner central zone comprising or consisting of a coating free topsheet area, the inner central zone extending along the longitudinal centreline.

12. The sanitary article according to claim 1, wherein the dry coating is free from non-encapsulated oil and/or emulsifier.

13. The sanitary article according to claim 1, wherein the dry coating comprises a water miscible vehicle.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The present invention will be further explained hereinafter by means of non-limiting examples and with reference to the appended drawings wherein:

(2) FIG. 1 shows a sanitary pad according to the present disclosure;

(3) FIG. 2 is an exploded view of the sanitary pad from FIG. 1;

(4) FIG. 3 is a bar chart illustrating results from a transfer study of a dry water-soluble coating according to the present disclosure; and

(5) FIG. 4 is a bar chart showing results from a study of the effect provided by a sanitary article according to the present disclosure.

DETAILED DESCRIPTION

(6) It is to be understood that the drawings are schematic and that individual components, such as layers of material are not necessarily drawn to scale. The sanitary article shown in the figures are provided as an example only and should not be considered limiting to the invention as disclosed herein.

(7) The sanitary article may be any one of feminine hygiene products such as sanitary napkins, panty liners, and also incontinence pads, diapers, inserts and the like. The diapers can be open diapers and pant diapers. The sanitary article may be an insert for a sanitary napkin incontinence pad or a diaper.

(8) In FIG. 1, the sanitary article 1 is in the form of a sanitary pad and comprises a topsheet 2 and a backsheet 3. The sanitary article 1 extends in a longitudinal direction L and a transverse direction T and has first and second longitudinal side edges 4,5 and a front edge 6 and a rear edge 7. The topsheet 2 comprises a first side 2a, being the user facing side, and a second side 2b, being an opposing side to the user-facing side. The sanitary article 1 comprises an absorbent core 8 arranged between the topsheet 2 and the backsheet 3. The topsheet 2 is provided with a dry coating in a coated zone 9 on the first side 2a of the topsheet 2. The coating is a water-soluble dry coating comprising allantoin and betaine. The absorbent core 8 is an optional feature for the sanitary article 1 of the present disclosure.

(9) The topsheet 2 may include or consist of fibrous nonwoven layer(s) being spunbonded, meltblown, carded, hydroentangled or wetlaid. Suitable nonwoven materials can be composed of natural fibers, such as woodpulp or cotton fibers, synthetic thermoplastic fibers, such as polyolefins, polyesters, polyamides and blends and combinations thereof or from mixtures of natural and synthetic fibers. The materials suited as topsheet material should be soft and non-irritating to the skin and be readily penetrated by body fluid, such as menstrual fluid and urine. The coating is applied to the topsheet as an aqueous formulation with the allantoin and betaine dispersed and/or dissolved in the aqueous formulation. The allantoin may be partly dissolved and partly dispersed in the aqueous formulation, depending on the amount of allantoin added to the formulation. The betaine is dissolved in the aqueous formulation. The formulation may be applied by any suitable method or combination of method, such as for example coating, slot coating, spraying, kiss rolling, dipping or printing. The aqueous formulation may be added to the topsheet prior to assembly of the sanitary article or to the topsheet of the assembled sanitary article, prior to or after cutting out the individual sanitary article. After drying of the topsheet, the dry coating is formed.

(10) One example on a coating composition applied to the topsheet may be demineralized water, glycerine (from 1 wt. % to 98.5 wt. %), betaine (from 1 wt. % to 10 wt. %), allantoin (from 0.5 wt. % to 5 wt. %), optionally Phenoxyethanol, optionally citric acid.

(11) The allantoin may be present in the dry coating in an amount within the range of from 0.0002 to 0.36 gsm, as measured over the total coated zone. Optionally, the allantoin may be present in the dry coating in amount within the range of from 0.0005 to 0.21 gsm, as measured over the total coated zone, or in an amount within the range of from 0.002 to 0.08 gsm. Such amounts of allantoin promotes a sufficient and improved transfer to the skin from the topsheet during use of the sanitary article and improved skin benefits.

(12) The betaine may be present in the dry coating in an amount within the range of from 0.001 to 1.2 gsm, as measured over the total coated zone. Optionally, the betaine may be present in the dry coating in amount within the range of from 0.0025 to 0.7 gsm, as measured over the total coated zone, or in an amount within the range of from 0.01 to 0.5, as measured over the total coated zone. Such amounts of betaine promote a sufficient transfer to the skin from the topsheet during use of the sanitary article and penetration into the skin, thereby providing improved skin benefits.

(13) In this FIG. 1, the topsheet 2 has a central coating free zone 12 arranged along a longitudinal centreline Lc of the sanitary article 1. The central coating free zone 12 may have a length corresponding to from 25% to 80% of the length of the topsheet, as measured at the longitudinal centreline Lc of the sanitary article 1. The coated zone 9 is arranged to provide an outer border delimiting an inner central zone, consisting or comprising of the central coating free zone 12.

(14) The topsheet 2 is furthermore printed with printing elements 10 provided in a printed zone 11. The printing elements 10 are printed on the second side 2b of the topsheet 2, i.e., on the opposite side to the side which the coated zone 9 is provided on. The printed zone 11 overlaps with the coated zone 9 and correlates to the coated zone 9, as seen in a depth direction, perpendicular to the longitudinal direction.

(15) The topsheet 1 furthermore has a central print free zone 13 arranged along the longitudinal centreline Lc of the sanitary article. The central print free zone 13 may have a length corresponding to from 35% to 80 of the length of the topsheet 2, as measured at the longitudinal centreline Lc of the sanitary article 1. The printed zone 11 is arranged to provide an outer border delimiting an inner central zone, consisting or comprising of the central print free zone 13.

(16) The dry coating may comprise a water miscible vehicle, such as glycerine, propylene glycol and/or PEG. The dry coating may be free from oil and from emulsifier, the dry coating could alternatively be free from non-encapsulated oil and/or emulsifiers. The glycerine may be used as a base in the dry coating and may be present in an amount of 1.0 to 98.5 weight %.

(17) The backsheet 3 may consist of a thin plastic film, e.g., a polyethylene or polypropylene film, a nonwoven material coated with a liquid impervious material, a hydrophobic nonwoven, all of which resist liquid penetration. Laminates of plastic films and nonwoven materials may also be used. The backsheet material can be breathable to allow vapor to escape from the absorbent structure, while still preventing liquids from passing through the backsheet material.

(18) An absorbent core 8 constitutes the absorbent structure of the article which acquires and stores bodily fluids. The absorbent core may be of any conventional kind. Examples of commonly occurring absorbent materials are cellulosic fluff pulp, tissue, highly absorbent polymers (so called superabsorbents), absorbent foam materials, absorbent nonwoven materials or the like. It is common to combine cellulosic fluff pulp with superabsorbent polymers in an absorbent core. Superabsorbent polymers are water-swellable, water-insoluble organic or inorganic materials capable of absorbing at least about 20 times their own weight of an aqueous solution containing 0.9 weight percent of sodium chloride. Organic materials suitable for use as a superabsorbent material can include natural materials such as polysaccharides, polypeptides and the like, as well as synthetic materials such as synthetic hydrogel polymers. The size and absorbent capacity of the absorbent core may be varied to suit different product types, such as sanitary napkins for adult incontinent persons or panty liners.

(19) A suitable technique for manufacturing the absorbent cores of the present disclosure is mat-forming through an air-laying process. In the process an air-permeable mould is provided. Fibrous material is air-laid into the mould and the mould is filled, whereby an absorbent core is produced with a desired amount of fibrous material.

(20) The sanitary article may furthermore comprise an acquisition layer arranged between the absorbent core and the topsheet and being bonded to the topsheet at least by means of embossings. It may however additionally be adhesively attached to the topsheet. The liquid acquisition layer is adapted to quickly receive and temporarily store discharged liquid before it is absorbed by the absorbent core. Such acquisition distribution layers may be composed of for example airlaid nonwoven, spunlace nonwoven or high loft nonwoven or foam materials. The nonwoven material may be hydrophilic. A hydrophilic material may be obtained by adding a surfactant.

(21) An air laid nonwoven can be produced with fluff, wood pulp, and here the fluff fibres are dispersed into a fast-moving air stream and condensed onto a moving screen by means of pressure and vacuum. The web can be bonded with resin and/or thermal plastic resin dispersed within the pulp. The web can be thermobonded (by heat), latex bonded (with adhesive) or multibonded (a combination of thermo and latex bonding) or mechanically bonded (high compression and temperature, bonding by hydrogen).

(22) A high loft material is a nonwoven material and may be substantially free from absorbing fibres and superabsorbent material. The high loft nonwoven material may comprise thermoplastic polymer fibres, and may be selected from but not limited to, polyesters, polyamides and polyolefins such as polyethylenes (PE) and polypropylenes (PP), and may be a mixture of any of these. The high loft material refers to low-density bulky fabrics, as compared to flat, paper-like fabrics. High loft webs are characterised by a relatively low density.

(23) FIG. 3 is a bar chart illustrating the results from a transfer study made with two sanitary articles according to the present invention. Eight test persons wore sanitary articles on three different spots on the volar forearms for three days (3 products per day). One spot was covered with products coated with formula A, one with products coated with formula B and one with reference product without any formula. After three days the skin in the test spots plus one additional spot where no product had been worn was harvested by means of tape stripping. The sample tape strips were extracted, analyzed by LC-MS/MS quantifying the betaine and allantoin content.

(24) As may be seen from FIG. 3, transfer of both betaine and allantoin could be readily detected on the skin, thereby providing the desired effect of the wearer of the sanitary article.

(25) TABLE-US-00001 TABLE 1 Formula A Formula B English INCI % w/w % w/w Demineralized water To 100% To 100% Glycerine 60% 9% Betaine 3.4% 4.2% Allantoin 1% 1% Phenoxyethanol 1% Citric Acid 0.1% Thickening agent 0.7%

(26) FIG. 4 shows the result from a study of the calming effect of a sanitary article according to the present disclosure. A calming effect was defined as a faster recovery from irritation back to normal skin status and was assessed by the transepidermal water loss (TEWL) as a measure of the skins barrier function by using an AquaFlux Model AF200 instrument (Biox Systems, London, UK). Eight test persons participated in the tests. At day 0, the baseline value of the skin of the volar forearms of each of the test person was measured. An irritating agent, 0.3% sodium lauryl sulfate (SLS), was added to three spots of the arms of the test person and the irritant remained on the arm for 24 h. After 24 h, at Day 1, the irritant was removed, and the skin status was measured. After the measurement one spot was covered with a sanitary article comprising the formula A, one spot was covered with a sanitary article comprising the formula B, one spot was covered with a sanitary article without formula (reference product), and one spot was left uncovered as an untreated reference. Test persons changed sanitary articles themselves so that three products were used per day and spot. Skin status was measured 24 h (Day 2) and 72 h (Day 4) after they started wearing products.

(27) As may be seen from FIG. 4, the sanitary articles provided with formulas A and B according to table 1 showed skin calming effects already after 1 day and still further skin calming effects was shown after 3 days of use of the sanitary articles.