WO2005053761A1

WO2005053761A1 - Absorbent article comprising a fragrance-containing back sheet

Info

Publication number: WO2005053761A1
Application number: PCT/KR2004/003167
Authority: WO
Inventors: Eun Jung Kang; Hyungbyum Kim
Original assignee: Yuhan Kimberly Ltd
Current assignee: Yuhan Kimberly Ltd
Priority date: 2003-12-04
Filing date: 2004-12-03
Publication date: 2005-06-16
Anticipated expiration: 2006-06-04
Also published as: KR101059641B1; CN1889984A; KR20050054120A; TWI275384B; TW200528074A; CN100536930C

Abstract

An absorbent article comprising a fragrance-containing back sheet is disclosed. Any fragrance known in the art may be contained in the back sheet, which is in the form of a film, nonwoven fabric or film/nonwoven laminate. Examples of suitable fragrances include lavender, lilac, rose, and the like. The absorbent article of the present invention can prevent contamination of the production line, other non-scented products and the wearer's skin.

Description

Description ABSORBENT ARTICLE COMPRISING A FRAGRANCE- CONTAINING BACK SHEET Technical Field

[1] The present invention relates to an absorbent article comprising a fragrance- containing back sheet (baffle). Background Art

[2] A wide variety of absorbent articles known in the art, such as baby diapers, training pants, adult incontinence articles, absorbent undergarments, sanitary napkins, panty liner, nursing pad, and the like, absorb body fluids insulted by various physiological processes. The body fluids absorbed in the absorbent articles generally have an unpleasant odor. Therefore, numerous means have been developed to control the odor in the absorbent articles.

[3] The most representative among such means is to incorporate a deodorant or fragrance in the absorbent articles.

[4] For example, Korean Patent No. 1996-15183 and U.S. Patent No. 5,429,628 disclose the incorporation of encapsulated odor-absorbing or fragrance-releasing agents in an absorbent core or top sheet of an absorbent article.

[5] U.S. Patent No. 5,591,146 discloses a sanitary napkin having an adhesive binder with perfume-carrying release agents, in which the adhesive binder allows the sanitary napkin to attach to a wearer's undergarments, and the perfume-carrying release agents are in the form of microcapsules which release perfume upon removal of a release liner from the adhesive binder.

[6] WO 98/51248 discloses an absorbent article comprising at least one touch-sensitive fragrance member located on a back sheet outer surface, in which the member contains microcapsulized fragrance-release agents.

[7] However, there are problems in that the conventional processes of preparing such an absorbent article further comprise the steps of encapsulating a deodorant or fragrance and applying the encapsulated deodorant or fragrance, and in that the encapsulated deodorant or fragrance are not applied uniformly to an absorbent article. Further, a deodorant or fragrance may directly contact the wearer's skin since it is incorporated in an absorbent core or top sheet of an absorbent article. Disclosure of Invention Technical Problem

[8] It is an object of the present invention to provide a fragrant absorbent article having none of the above-mentioned problems. Technical Solution

[9] An absorbent article according to the present invention is characterized in that a fragrance is incorporated in a back sheet and the fragrance is not encapsulated.

[10] The absorbent article according to the present invention can be described as follows.

[11] The absorbent article has a liqiid permeable top sheet, absorbent core and liqiid impermeable back sheet as conventional absorbent articles. In the present invention, a non-encapsulated fragrance is incorporated in the back sheet.

[12] All known fragrances generally used in the art may be used in the present invention. Examples of suitable fragrances include single floral-type fragrances such as lavender, lilac, rose and jasmine; floral boucμet-type fragrances, which are a mixture of single floral-type fragrances; citrus-type fragrances such as lemon or orange; oriental-type fragrances such as musk, amber and civet; green or woody-type fragrances; aliphatic aldehyde-type fragrances, and the like. Among the above, single floral-type fragrances such as lavender, lilac and rose are preferably used in the present invention.

[13] The composition of the lavender fragrance which can be used in the present invention is as follows: lavender oil 40 to 60%, linalool or linalool oxide 10 to 30%, citronelol 5 to 10%, isobornyl acetate 10 to 20% and camphor 5 to 10%.

[14] The camphor slightly intensifies the lavender scent.

[15] A lavender fragrance consisting of linalyl acetate 25 to 40%, lavandin oil 40 to 60%, linalool or linalool oxide 5 to 15% and lemon oil 0.01 to 5% may also be used in the present invention.

[16] The composition of the lilac fragrance used in the present invention is as follows: cinnamic aldehyde 30 to 60%, ethyl linalool 10 to 30%, iso-eugenol 10 to 30%, linalool 10 to 30%, terpineol 10 to 30% and phenyl ethyl alcohol 5 to 15%.

[17] The back sheet according to the present invention may be in the form of a film, nonwoven fabric or film/nonwoven fabric.

[ 18] First, the back sheet in the form of a film will be described.

[19] A nuniier of manufacturing techniqies may be used to manufacture the back sheet in the form of a film according to the present invention, for example, casting or expansion molding techniqies. For longevity, the back sheet is preferably manufactured by blending a fragrance with a thermoplastic polymer constituting a back sheet matrix to prepare the master batch (hereinafter, a fragrance-containing master batch); mixing the fragrance-containing master batch and a conventional baffle master batch; and casting the mixture through a T-die at about 170 to 240°C, preferably about 180 to 230°C, as described below in detail.

[20] The fragrance-containing master batch and the baffle master batch are mixed in the desired ratio. The mixture is then introduced into an extruder. After being melted and mixed in said extruder, the mixture can be fully dispersed, and impurities are removed from the mixture using a screen pack Thereafter, it is casted into a film through the dice of a T-die. The casted film is passed through a cooling roll, in which it is preferable that the temperature of the cooling roll is maintained at 10 to 30°C, preferably 15 to 25°C,lower than that of a conventional roll (20 to 35°C, preferably 25 to 30°C), in order to maintain the scent. The film is slit and wound in the desired dimension. A corona treatment, embossing or printing step can be further included in the process if desired. The back sheet thus prepared can be used in the present invention.

[21] A fragrance-containing master batch used in the present invention consists of a thermoplastic polymer 30 to 50%, a fragrance 1 to 20% and an additive 40 to 60%. A baffle master batch used in the present invention consists of a thermoplastic polymer 40 to 60% and an additive 40 to 60%. An additive in the fragrance-containing master batch and the baffle master batch may be an antioxidant, a filler particle, a dyestuff, and the like in accordance with the desired properties.

[22] The respective thermoplastic polymers of the fragrance-containing master batch and the baffle master batch can be different from or identical to each other. Examples of such a thermoplastic polymer include without limitation very low density polyethylene, low density polyethylene, high density polyethylene, polypropylene, copolymer of ethylene and C -C alpha-olefins, copolymer of propylene with ethylene ₃ 12 and/or C -C alpha-olefins, and flexible polyolefins including propylene-base 4 12 polymers having both atactic and isotactic propylene groups in the main polypropylene chain, elastomers - for example, polyurethanes, copolyether esters, polyamide polyether block copolymers, ethylene vinyl acetate copolymers, block copolymers having the general formula A-B-A or A-B such as copoly(styrene/ethylene-butylene), styrene-poly(ethylene-propylene)-styrene, styrene-poly(ethylene-butylene)-styrene, polystyrene/poly(ethylene-butylene)/polystyrene, poly(styrene/ethylene-butylene/styrene), and the like.

[23] The fragrance-containing master batch and the baffle master batch may be mixed in any ratio. It is preferable that two master batches are mixed in a ratio of about 99: 1 to 40:60 wt%, preferably about 96:4 to 80:20 wt%, in view of the maintenance and the desired intensity of the scent. Therefore, the applied amount of a fragrance is about 0.01 to 12 wt%, preferably about 0.05 to 5 wt%, based on the total weight of the back sheet.

[24] In addition, the breathable back sheet prepared by casting a fragrance-containing master batch having a filler particle, such as CaCO with a baffle master batch into a 3 film, and by uniaxial or biaxial stretching the film through three steps consisting of the preheating step, stretching step and annealing step can be used in the present invention. The stretching step is comprised of two (2) steps, and the temperature of the stretching step is set in view of volatilization and decomposition of the fragrance, about 20 to 70°C being preferred, about 40 to 45°C being more preferred. The elongation ratio is about 160 to 250%, preferably about 180 to 220%. The annealing step is carried out at about 20 to 100°C, preferably 70°C or less, in view of volatilization and decomposition of the fragrance.

[25] The film thus stretched should have a thickness, which permits structural integrity and forms a liqiid barrier. After stretching, the film should have a thickness of about 50 to 300 microns, preferably about 100 microns.

[26] The back sheet according to the present invention may also be a nonwoven fabric prepared by any conventional processes with the above fragrance-containing master batch and baffle master batch. Examples of suitable nonwoven fabrics include a spunbond web, a meltblown web, a thermal-bonded carded web, a thru-air bonded carded web, a spunlace web, a spunbond-meltblown-spunbond web, a spunbond- meltblown-meltblown-spunbond web, and the like, preferably a spunbond- meltblown-spunbond web and a spunbond-meltblown-meltblown-spunbond web.

[27] Further, the back sheet according to the present invention may be a film/nonwoven laminate. The film/nonwoven laminate can be obtained by laminating the film having a fragrance prepared with a fragrance-containing master batch and a baffle master batch as described above to a conventional nonwoven web; or by laminating the nonwoven fabric having a fragrance prepared with a fragrance-containing master batch and a baffle master batch as described above to a conventional film; or by laminating the film having a fragrance prepared as described above to the nonwoven fabric having a fragrance as described above using conventional adhesives, such as solvent type glue, hot melt adhesive and cold glue, or thermal bonding techniqies known in the art. The applied amount of a fragrance is about 0.01 to 12.0 wt% based on the total weight of the back sheet.

[28] A top sheet and an absorbent core used in conventional absorbent articles may be used in the present invention. The top sheet to be used may be manufactured from a wide variety of materials, such as porous foams, reticulated foams, apertured plastic films, nonwoven webs, natural fibers, synthetic fibers, or a coπimation of natural and synthetic fibers. The top sheet, for example, can comprise a spunlace nonwoven web, a spunbond fiber web of polyolefin fibers or a bonded-carded web composed of natural and/or synthetic fibers. In this regard, the top sheet may be composed of substantially hydrophobic material treated with a surfactant or otherwise processed to impart the desired level of wettability and liqiid permeability. Examples of the top sheet are described in U.S. Patent No. 5,879,343, U.S. Patent No. 5,490,846, U.S. Patent No. 5,364,382 and US. Patent Application No. 09/209,177.

[29] The absorbent core to be used may include one or more absorbent materials such as superabsorbent particles, wood pulp fluff fibers, synthetic weed pulp fibers, synthetic fibers and conϋnations thereof. The absorbent core may have any of a number of shapes, the size of which will vary with the desired lading capacity, the intended use of the absorbent article and other factors known to those skilled in the art. However, the absorbent article according to the present invention may have no absorbent core. Best Mode for Carrying Out the Invention

[30] The present invention will be further illustrated in the following examples, which are not intended to limit the scope of the present invention.

[31] <Example 1>

[32] 15 wt% of a fragrance-containing master batch comprising 10 wt% of a lavender fragrance composition (48 wt% lavender oil, 22 wt% linalool, 8 wt% citronelol, 12 wt% isobornyl acetate and 10 wt% camphor); 40 wt% of a low density polyethylene; and 50 wt% of a mixture of tris(2,4-di-tert-butylphenyl)phosphate and tetra s(methylene 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate methane, as an- tioxidants, as well as 85 wt% of baffle master batch comprising 8 wt% of a low density polyethylene; 39.3 wt% of a linear low density polyethylene; 51 wt% of CaCO ; and 3 1.7 wt% of TiO were mixed. The resulting mixture was then casted through a T-die at 2 about 200°C to produce a film. [33] The film thus obtained was uniaxially stretched at an elongation ratio of about 200 % and at a temperature of about 40°C to form a breathable film for the back sheet. [34] A panty liner was prepared using the above-obtained film as a back sheet.

[35] <Example 2>

[36] The procedure in Example 1 was repeated except that a lavender fragrance composition containing 30 wt% linalil acetate, 40 wt% lavandin oil, 15 wt% linalool and 5 wt% lemon oil was used as a fragrance to form a breathable film for the back sheet. A panty liner was prepared using the above-obtained film as a back sheet.

[37] <Example 3>

[38] The procedure in Example 1 was repeated except that a lilac fragrance composition containing 40 wt% cinnamic aldehyde, 15 wt% ethyl linalool, iso-eugenol, 15 wt% linalool, 10 wt% terpineol and 5 wt% phenyl ethyl alcohol was used as a fragrance to form a breathable film for the back sheet. A panty liner was prepared using the above- obtained film as a back sheet. Industrial Applicability

[39] When absorbent articles are prepared by mixing a fragrance with a baffle master batch and then forming a back sheet as in the present invention, the articles have the advantages of avoiding possible contamination to the wearer's skin and an additional process of applying fragrance onto the absorbent articles. Further, the impression of the articles to users is improved.

[40] The en±odiments illustrated and described above are provided as examples of certain preferred en±odiments of the present invention. Various changes and modifications can be made from the embodiments presented herein by those skilled in the art without departing from the scope of this invention.

Claims

[I] An absorbent article comprising a back sheet containing non-encapsulated fragrance.

[2] The absorbent article of Claim 1, wherein the back sheet is a film prepared from the mixture of a fragrance-containing master batch and baffle master batch.

[3] The absorbent article of Claim 2, wherein the back sheet is a film prepared by introducing a fragrance-containing master batch and a baffle master batch into an extruder, melt-mixing the mixture, casting the mixture through a T-die at 170 to 240°C and passing the resultant through a cooling roll at 10 to 30°C.

[4] The absorbent article of Claim 1, wherein the back sheet is a nonwoven fabric prepared from the mixture of a fragrance-containing master batch and baffle master batch.

[5] The absorbent article of Claim 4, wherein the back sheet includes a spunbond- meltblown-spunbond web or spunbond-meltblown-meltblown-spunbond web.

[6] The absorbent article of Claim 1, wherein the back sheet is a film/nonwoven laminate prepared by introducing a fragrance-containing master batch and a baffle master batch into an extruder, melt-mixing the mixture, casting the mixture through a T-die at 170 to 240°C, passing the resultant through a cooling roll at 10 to 30°C to form a film, and laminating the film with a nonwoven web using an adhesive or by heat sealing.

[7] The absorbent article of Claim 1, wherein the back sheet is a film/nonwoven laminate prepared by laminating a nonwoven fabric prepared from a mixture of a fragrance-containing master batch and baffle master batch to a film using an adhesive or by heat sealing.

[8] The absorbent article of any of Claims 1 to 7, wherein the fragrance is used in an amount ranging from 0.01 to 12.0 wt% based on the total weight of the back sheet.

[9] The absorbent article of any of Claims 2 to 7, wherein the baffle master batch comprises 40 to 60 wt% a thermoplastic polymer and 60 to 40 wt% an additive.

[10] The absorbent article of Claim 9, wherein the thermoplastic polymer is selected from the group consisting of very low density polyethylene, low density polyethylene, high density polyethylene, polypropylene, copolymer of ethylene and C -C α-olefin and terpolymer of propylene, ethylene and C -C α-olefin. 3 12 4 12

[II] The absorbent article of Claim 9, wherein the additive is selected from the group consisting of an antioxidant, dye, filler particle and conϋnations thereof.

[12] The absorbent article of any of Claims 2 to 7, wherein the fragrance-containing master batch comprises 30 to 50 wt% a thermoplastic polymer, 1 to 20 wt% a fragrance and 40 to 60 wt% an additive.

[13] The absorbent article of Claim 12, wherein the thermoplastic polymer is selected from the group consisting of very low density polyethylene, low density polyethylene, high density polyethylene, polypropylene, copolymer of ethylene and C -C α-olefin and terpolymer of propylene, ethylene and C -C α-olefin. 3 12 4 12

[14] The absorbent article of Claim 12, wherein the additive is selected from the group consisting of an antioxidant, dye, filler particle and conϋnations thereof. [15] The absorbent article of any of Claims 2 to 7, wherein the ratio of the baffle master batch to the fragrance-containing master batch ranges from 96:4 to 80:20 wt%. [16] The absorbent article of Claim 3 or 6, wherein the casted film is stretched at 35 to 60°C in an elongation ratio of 160 to 250%. [17] The absorbent article of Claim 16, wherein the stretched film is annealed at 20 to 100°C. [18] The absorbent article of any of Claims 1 to 7, wherein the fragrance is a lavender- or lilac-scented fragrance. [19] The absorbent article of Claim 18, wherein the fragrance is a lavender-scented composition comprising 40 to 60 wt% lavender oil, 10 to 30 wt% linalool or linalool oxide, 5 to 10 wt% citronelol, 10 to 20 wt% isobornyl acetate and 5 to 10 wt% camphor. [20] The absorbent article of Claim 18, wherein the fragrance is a lavender-scented composition comprising 25 to 40 wt% linalil acetate, 40 to 60 wt% lavandin oil, 5 to 15 wt% linalool or linalool oxide and 0.01 to 5 wt% lemon oil. [21] The absorbent article of Claim 18, wherein the fragrance is a lilac-scented composition comprising 30 to 60 wt% cinnamic aldehyde, 10 to 30 wt% ethyl linalool, 10 to 30 wt% iso-eugenol, 10 to 30 wt% linalool, 5 to 15 wt% terpineol and 5 to 15 wt% phenyl ethyl alcohol.