Title of Invention

HOT MELT ADHESIVE COMPRISING SUPER ABSORBENT PARTICLES OF SUBSTANTIALLY ANGLE-LACKING SHAPE

Abstract

The present invention relates to a liquid absorbent thermoplastic composition, which contains particles of a superabsorbent material having angle-lacking shapes. Said composition is particularly suitable to be used in absorbent articles for personal hygiene, specifically in disposable absorbent articles, which preferably comprise one or more regions in which they are transparent. In particular, the absorbent core of such transparent absorbent articles can be made from the liquid absorbent thermoplastic composition of the present invention.

Full Text

Field of invention The present invention relates to a hot melt adhesive which contains particles of a superabsorbent material having angle-lacking shapes. Said adhesive is particularly suitable to be used in absorbent articles for personal hygiene, specifically in disposable absorbent articles, which preferably comprise one or more regions in which they are transparent. In particular, the absorbent core of such transparent absorbent articles can be made from the liquid absorbent thermoplastic composition of the present invention. Background of the invention Absorbent articles for feminine hygiene, such as sanitary napkins and panty liners, are widely known in the art. The purpose of such articles is to absorb and retain body fluids, which are naturally excreted from the body. Such body fluids are any water based fluids or liquids excreted from the human body such as urine, menses, serum, blood, sweat, mucous as well as other aqueous solutions generally defined as body fluids. These articles typically comprise a liquid- pervious topsheet as wearer-facing layer, a liquid-impervious backsheet as garment-facing layer and an absorbent core between topsheet and backsheet. The body fluids are acquired through the topsheet and subsequently stored in the absorbent core. The backsheet prevents the absorbed fluids from wetting the wearer's garment. It is also widely known in the art that it is beneficial for the absorption and retention characteristics of absorbent articles when portions of the article, typically the absorbent core, comprise superabsorbent materials, such as absorbent gelling material (AGM). An example for such articles is described in WO-A- 01/64154. Recent fashion trends have led to extensive use of cloths with a certain degree of translucency, which are especially worn by younger people, in particular women. Thus, as thereby the undergarment or even certain body portions can be noticed through such translucent cloths, a need exists for providing absorbent articles, which are not noticeable through the translucent cloths, as otherwise feelings of annoyance or irritation for the wearwer of the such articles or other people could arise. Generally, absorbent articles are white or lightly pink coloured bat are always constructed of a matrial having a certain colour. As the backsheet is the part of the article with the highest potential of being noticed adapting its colour in a way, which harmonize with the colour of the undergarments would be beneficial. However, as the colour of the andergerment is usually different from garment it would be impractical if the user bad to purchase absorbent articles in different colours according to the actual undergarment. Thus, it would be beneficial to provide absorbent articles of a colour, which does not ccntrast with any other colour. This condition is only fulfilled by substantially transparent, colourless articles. A substantially transparent absorbent article would require to be built exclusively from transparent components. Transparent topsheet and backsheets can be provided by using transparent polymeric films or thin pigment-free nonwovens. A problem to be solved is to provide an absobeat core, which is suitable to be used m substantially transparent absorbent articles. Traditionally, absorbent cores for use in disposable absorbent articles for feminine hygiene, such as sanitary napkins or panty liners, are made of a fibrous material, such as wood pulp, cotton or rayon. Typically, those cores comprise supetabsorbent meterial for absorbing liquids and optional materials for e.g. controlling malodours. The drawback of such cores is the fact that all those materials are usually white coloured and could thus be easily noticeable through transparent topsheet and transparent backsheets. To address this problem absorbent cores, which substantially consist of a polymaric material containing superabsorbent material therein have been suggested in die art For instance, EP-A-1,138,293 discloses a subsantially transparent absorbent article, comprising an absorbent ccne, which consists of a hot melt adhesive containing particles of an absorbent gelling material. Adhesive meterials having liauied absorbent properties are already known in the art US 4,952,618 discloses hydrocollcad/adhesive compositionsa.,containing polycationic hydtocoiloid particles, for use especially in wound dressings. Another watar-absorbent composition is disclosed in US 4,977,211. Has document suggests the composition to be made from three components, which are a water-absorptive resin, a polyolefin resin and an ethylene/α-olefin copolymer. WO-A-98/275S9 discloses a swellable hot melt adhesive for use in the prodactical of waterlight constructions, especially waterlight cables. WO-A-99/S7201 discloses a thermoplastic composition which can be a hot melt! adhesive, ccmtaioing {Mtrdcles of a siQ>eiabsotbait polymBi' for the ineventioD of gel blocking m absorbent articles. EP-A-1013291 discloses a hot melt adhesive ccHitaining fltdd absortangpdymers for ose in e.g. absorbent prodtKts, in particular for bonding substrates sudi as polymenc films to^ther. WO-A-01/64153 and WO-A-01/641SS both disclose absorbent structures made by co-extn^ing a thermoplastic polymsr with low melting pdbat and a siq>erabsari)ent polynoer for use as absorbent compoamt in hygLeoe articles. WO-A-96/16624 discloses a stretebaide absorbeot core for stretcloble absorbent articles. It is suggested in this document to bdld a core fiom supetabsoitient particles, which are incosporated into a n^wotk of a stc^chal^ lander, which is preferably a meltblown adhesive with elastic cooqionents. US 5,567,744 discloses a high water-absorbent conq>ositi However, conv^itiGnal absorbent compositions as described above typically suffer from a contradictioQ between sifgdent hquid-absorbeDcy for bemg used in absorboit articles and appnqiriate viscosity for being processed cm conventional ccmverter lines for produdng such absoibrat articles. Hiis contradktion is caused by the fact that the higher the amount of superabsorbent material particles used in the ccHxqpositi Ibus, dMsre fxists a need to provide an InptDved liquid absogA)ait thermoplastic camposition, which has a good wmer-alnarbency and wMdi are easily {trocessable by having for exaoqile a viscosity at 1J50°C of not more dun 15000 q>s. A further existing need is to provide an improved liquid absorbent thermoplastic composition, which has a good water-absorbency and which are easily processable by having for example a viscosity at 150°C of not ,pre than 15000 cps, and which has improved mechanical proprecties, such as high internal cohesion of the composition. Furthermore, there exists a need for a cmposition of the aforementioned kind, which is substantially transparent so that it can be used in substantially transparent absorbent articles. It has now surpriaingly been found that all the above needs can be satisfied by selecting particular superabsorbent particles, namely superabsorbent particles having a substantially angle-lacking, preferably approxiamately spherical shape, and an average particle dianeter in dry state of between 0.1 µm and 500 µm Superabsorbent particles having an angle-lacking shape are known from EP-A-349,241, where a process for their production is suggested. However, there is no mentioning in the prior art towards the use of such particles in liquid-absorbent thermoplastic compositions, let alone in absorbent articles of personal hygiene. Summery of the Invention The present invention relates to a liquid absorbent thermoplastic composition comprising a polymeric base material and particles of superabsorbent material, wherein said particles have a substantially angle-lacking shape and an average diameter of firom 0.1 to 500 µm. The present invention relates also to the use of said composition in the absorbent core of disposable absorbent articles for personal hygiene, prefrarably transparent ones, and/or as loading indicator in such articles. Brief description of the figure Figure 1 shows a magnified view of approximately spherical particles of the superabsorbent matraial Aquakeep 10 SH-NF from Sumitomo Seika. The actual particle size of the particles showed in Figure 1 is between 20 µm and 30 µm. Hgure 2 illustrates the test procedure for determining colour transparency. Detailed description of the invention The term 'substantially transparemt' as used herein refers to the ability of a material or combination of materials to transmit viable light through the body of the material. It is recognized that every material will removed a certain fraction of light and therefore complete transparency cannot exist There are various possibilities to measure transparency, one of which is identified in the test methods section herein. The liquid absorbent thermoplastic composition of the present invention preferably has a transparancy value of at least 50%, preferably at least 60%, mare preferably at least 70%, even more preferably at least 80% and most preferably at least 90% according to the test method as disclosed herein (E versus reference). Transparency has been measured with a homogeneneous flat film of the liquid absorbent thermoplastic composition having a basis weight of 100 g/m2 and a thickness of 100 µm,. The term 'absorbent artide' is used herein in a very broad sense, including any article being able to receive and/or absorb and/or contain and/or retain body fluids. The absorbent article of the present invention typically compises a fluid pervious topsheet as the layer contacting the skin of the wearer in use, a fluid impervious backsheet, which is preferably but not necessarily water vapour and/or gas pervious as the layer contacting the garment of the wearer in use, and an absorbent core, being positioned between the backsheet and the topsheet All layers of the absorbent article (e.g. the topsheet, the backsheet and the absorbent core) have a wearer- and a garment-facing surface. When referring to absorbent articles, the requirment for transparency according to the present invention is that a colour be visually recognizable when viewed by the human eye through a region. of the article, which is transparent through the thickness of said article. According to a preferred embodiment of the present invention, the article has at least one transparent region having a transparency value of at least 50%, preferably at least 60%, more preferably at least 70%, even more preferably at least 80% and most jneferably at least 90% through the thickness of the article (B versys reference). Particularly prefened abscabent articles in the context of the present inventian are disposable absorbent articles. Preferred disposable absorbent articles according to the present invention are incontinence articles, perspiration pads, sanitary napkins or panty liners. The term 'disposalde' is used herein to describe absorbent articles, which are not intended to be lauundered or otherwise restored or reused as an artide (i.e they are intended to be discarded after a single use and preferably to be recyclod composted or otherwise disposed of in an environmentally compatible manner). The term 'use', as used herein, refers to the period of lime that starts when the absorbent article is actually put in contact with the anatomy of the user. By 'body fluid' it is meant herein any water based fluids or liquids excreted from the human body such as urine, menses, serum, blood, sweat, mucous as well as other aqueous solutions generally defined as body fluids, but it is not intended to exclude other water based fluids. The term 'thermoplastic' as used herein refers to the ability of materials to soften and possibly even melt at raised temperatures and to harden again at reduced temperatures, while having substantially the same material characteristics after the hardening step as before the softening and/or melting step. The liquid absorbent thermoplastic composition of the present invention comprises a polymeric base material and particles of superabsorbent material. Typically, the liquid absorbent thermoplastic composition of the present invention comprises from 5% to 99% by weight of the total composition of a polymeric base material and from 1% to 95% by weight of the total composition of particles of superabsorbent material. The liquid absorbent thermoplastic comosition of the present invention comprises as an essential element particles of superabsorbent material. Preferably, the liquid absorbent thermoplastic composition of the present invention comprises from 1% to 95%, preferably from 10% to 90%, more preferably from 30% to 70% and most preferably from 40% to 60% by weight of the total composition of particles of superabsorbent material. Any superabsorbent material known to the skilled person and used in absorbent articles, such as feminine care absorbent articles (e.g. sanitary napkins, panty liners or incontinoice articles) or baby care absorbent articles (e.g. diapers) can be used herein. The particles of superabsorbent material for use herein are characterized by their substantially angle-lacking, preferably approximately spherical shape and their average particle size of from 0.1 µm to 500 µm Without the intention to be bound by any particular theory it is believed that the friction between angle-lacking particles is lower than the one between particles with angles, because mutual engagement or hooking together of the particles is much more likely in case of particles having a rougher surface, such as particles having shapes with angles. Because of this it is believed that the viscosity of a molten liquid absorbent thermoplastic composition having particles therein with angle-lacking shape is significantly lower then the viscosity of a molten liquid absorbent thermoplastic composition with particles having shapes with angjes at the same tenperature, such as those disclosed by the prior art described infra. The liquid alworbent thermoplastic conposition of the present invention typically has a viscosity at about 150°C of not more than 15000 centipoises, preferably not more than 12000 centipoises, more preferably not more than 10000 centipoises, even more preferably not more than 8(KX) centipoises and most preferably not more than 5000 centipoises. The viscosity values discussed herein have been determined by the viscosity test method as disclosed herein. It is also believed that particles with substantially angle-lacking shape have a higher transparency due to their smoother surface compared to particles with a rougher surface due to shapes with angles, like the ones being used in the prior art as described infra. 'Particles' as used herein refers to discrete flakes, fibres, beads and the like or mixtures thereof of a certain material, in particular superabsorbent material The term particles herein also comprises agglomerations or aggregations of discrete flakes, fibres, beads and tbe like of a certain material. 'Particle size' as used herein means the weighted average of the smallest dimension of the individual particles. 'Angle lacking' as used herein refers to the shape of particles, which can be of spherical or non-spherical shape and which have no sharp angles in their shapes and on their surfaces. According to the present invention the shape of an amount of particles is considered as angle lacking, if at least 70%, preferably at least 80% more preferably at least 90%, even more preferably at least 95% and most preferably 100% of the regarded amount of particles have an angle lacking shape according to the definition hereinbefore. 'Spherical' as used herein refers to particles having an angle-lacking shape, which have a substantially roimdish or ball-like shape. A sphencal particle according to the present invention is characterized in that the ratio of its largest dimension divided by its smallest dimension is not larger than 1.5 and is preferably 1. The average particle size of the particles of superabsorbent material for use herein is in dry state from 0.1 µm to 500 µm preferably from 1 µm to 200 µm, more preferably from 10 µm to 100 µm , even more preferably from 10 µm to 60 µm and most preferably from 15 µm to 40 µm Without the intention to be bound by theory it is believed that tbe smaller the average diameter of the particles of superabsorbent material are, the better their absorbency towards liquids is. Indeed the effective surface area, which is in contact with the liquid to be absorbed, is much larger for a large quantity of small particles compared to a smaller quantity of larger particles of the same overall weight. A particle size of the superabsorbent particles of smaller than 0.1 µm results in process problems, as by the very fine particles the generation of dust while handling those particles, e.g. during manufacture of the composition of the present invention, is highly likely. On the other hand, when using superabsorbeat particles being larger in diameter than 500 µm, it is not possible anymore to provide thin layers of the composition of the present invention. The minimum thickness of such a layer is determined by the diameter of the superabsorbent particles. 'Superabsoribent material' as used herein means materials, which are capable of absorbing at least five times of their weight of water or aqueous liquids. Preferred superabsorbeut materials are anionic absorbent gelling material as well as cationic absorbent material, such as chitin, chitosan or chitosan compounds, or combinations of anionic and cationic superabsorbent material. Particularly preferred superabsorbent materials for use herein are anionic absorbent gelling materials, i.e., absorbent gelling materials, which are predominantly negatively charged These absorbent gelling materials can be any material having superabsorbent properties in which the functional groups are aninic, namely sulphonic groups, sulphate groups, phosphate groups or carboxyl groups. Preferably the functional groups are carboxyl groups. Particularly preferred anionic absorbent gelling materials for use herein arc synthetic anionic absorbent gelling materials. Generally, the functional groups are attached to a slightly cross-linked acrylic base polymer. Superabsorbent materials for- use according to the present invention can be made by polymerisation of ethylenically unsaturated monomers. Examples of ethylenically unsaturated monomeis are acrylic acid, methacrylic acid, crotonic acid, maleic acid and its anhydride, fumaric acid, itaconic acid, and 2-(meth)acryloylethanesulfonic acid, and 2-(meth)acryloylpropanesulfoniic acid, and 2-(meth)acryiamido-2-methylpropanesulfonic add, vinylsulfonic add, styrenesulfonic acid and the like and their salts; monomers containing nonionic hydrophilic substituents such as (n:tfth)acrylamide, N-substituted (meth)acrylamides, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, polyethylene glycol (meth)acrylate and the like; monomers of cationic character such as N,N'-dimethylaniinoethyl (meth)acrylate, N,N'-diethylaminoethyl (meth)acrylate, N,N,N,N-diethylaminppropyl (meth)acrylate, N,N'-dimethylaminopropyl (meth)acrylamide, and the like and their quartary salts. The polymers of those monomers can be used alone or mixtures of the polymers two or more of those monomers can be used as well. Copolymers of these monomers can also be used. Especially preferred polymers for use as superabsorbent material are cross-linked polyacrylates. hydrolyzed acrylonitrile grafted starch, polyacrylates grafted starch and isobutylene maleic anhydride copolymers. Suitable crosslinldng agents for facilitating the cross-linking of the preferred absorbent gelling material for use as superabsorbent material are N,N'-methylene-bis(meth)acrylamide, N- methylol(meth)acrylamide, ethylene glycol (meth)acrylate, polyethylene glycol (meth)acrylate, propylene glycol (meth)acrylate, polypropylene glycol (meth)acrylate, glycerol tri(meth)acrylate, glycerol mono(meth)acrylate, polyfimctional metal salts of (meth)acrylic acid, trimethylolpropane tri(meth)acrylate, triallylamine, triallyl cyanulate, triallyl isocyanulate, triallyl phosphate, glycidyl (meth)acrylate. As examples of agents having reactive functional groups for example, in a case that a monomer has a carboxyl and/or carboxykte group, polyhydric alcohol derivatives such as ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, glycerol, polyglycerol, propylene glycol, diethanoiamine, thethanolamine. polyoxypropylene, oxyethyleneoxypropylene block co-polymer, pentaerythritol, and sorbitol; polyglycidyl derivatives such as ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, glycerol polyglycidyl ether, diglycerol polyglycidyl ether, polyglycerol polyglycidyl ether, sorbitol polyglycidyl ether, pentaerythritol polyglycidyl ether, propylene glycol diglycidyl ether, and polypropylene glycol diglycidyl ether, aziridine derivatives and related compounds such as 2,2- bishydroxymethylbutanol-tris (3-[l-aznidinyl) propionate], 1,6-hexamethylene-diethylene urea, and diphenylmethane-bis-4,4'-N,N'-diethylene urea, haloepoxyl compounds such as epichlorohydrin and alpha -methylchlorohydrin; polyaldehydes such as glutar aldehyde and glyoxal; poly amine derivatives such as ethylene diamine, diethylene diamine, triethylene tetramine, tetraethylene pentamine, pentaethylene hexamine, and polyethylene hexamine; polyisocyanates such as 2,4-toluylenediisocyanate and hexamethyienediisocyanate; polyvalent metal salts such as aluminium chloride, magnesium chloride, calcium chloride, aluminium sulfate, magnesium sulfate, and calcium sulfate. Subject to consideration upon reactivity, these crosslinldng agents can be used as a mixture of more than two, but it is usually preferable to use a crosslinldng agent having polymezizable unsaturated groups The preferred, slightly cross-linked, hydrogel-forming absorbent gelling matraials will generally be employed in their partially neutralized form. For purposes described herein, such are considered partially neutralized when at least 25 mole percent, and preferably at least 50 mole percent of monomers used to form the polymer are add group-containing monomers, which have been neutralized with a salt-forming cation. Suitable salt-forming cations include alkali metal, ammonium, substituted ammonium and amines. This percentage of the total moaomers utilized. which are neutralized acid group-containg monomers, is referred to as the "degree of neutralization". Typically, commercial absorbent gelling materials have a degree of neutralization somewhat from 25% to 90%. Examples for cationic superabsorbent materials for use herein are chitin, chitosan, chitosan salts, such as chitosonium lactate or chitosonium pyiollidone carboxylate (as disclosed in WO-A-98/07618), modified chitosans as disclosed m WO-A-87/07618, US 5,378,472 or EP-A-737,692, cross-linked chitosans, or mixtures thereof. Figure 1 shows approximately sphaical particles of a superabsorbent material suitable for use herein, namely particles of Aquakeep 10 SH-NF, available from Sumitomo-Seika, having a particle size of between 20 µm and 30 µm. Another example for substantially angle-lacking particles of superabsorbent material suitable for use herein is Aquakeep 10 SH-P, also from Sumitomo-Seika. The latter material is often referred to as 'broccoli-like', as the individual particles of this material are basically an agglomeration of substantially spherical particles of superabsorbent material. The liquid absorbeut thermoplastic composition of the present invention comprises as a further essential element a polymeric base material. Typically, the liquid absorbent thermoplastic composition of the present invention congprises from 5% to 99%, preferably 10% to 90%, more preferably from 30% to 70%, most preferably from 40% to 60% by weight of the total composition of a polymeric base material. Any polymeric base material known to the skilled person and used in the construction of absorbent articles, such as feminine care absorbent articles (e.g. sanitary napkins, panty liners or incondnence articles) or baby care absorbent articles (e.g. diapers) can be used herein. The polymeric base materials for use herein comprise from 5% to 99%, preferably 10% to 90%, more preferably from 30% to 70%, most preferably from 40% to 60% per weight of thermoplastic polymers as an essential dement A variety of different thermoplastic polymers are suitable for use herein. Exemplary thermoplastic polymers for use with the present invention are block copolymers, amorphous and Crystalline polyolefins including homogeneous and substantially linear ethylene/alpha-olefin intetpolymeas, interpolymers of ethylene such as ethylene-vinyl-acetate (EVA), ethylene-methyl-acrylate CEMA) and ethylene n-butyl acrylate (EnBa) and mixtures thereof. A wide variety of 'block copolymers' are useful in the present invention The group of block copolymers includes linear copolymers of the triblock A-B-A or the diblock A-B type, or radial co-polymer structures having the formula (A-B),. The A blocks are non-elastic polymer blocks, typically polyvinylarene blocks, the B blocks are unsaturated conjugated dienes, such as poly(monoalkenyl) blocks, or hydrogenated versions thereof, x denotes the number of polymeric arms, and x is an integer greater than or equal to one. Suitable block A polyvinylarenes include, but are not limited to polystyrene, polyalpha-methylstyrene, polyvinyltoluene, and combinations (hereof. Suitable block B poly(monoalkenyl) blocks include, but are not limited to conjugated diene elastomers such as for example polyfautadiene or polyisoprene or hydrogenated elastomers such as ethylene butylene or ethylene propylene or polyisobutylene, or combinations thereof. Commercial examples of these types of block copolymers include Europrene™ Sol T from EniChem, KratonTM elastomers from Shell Chemical Company, VectorTM elastomers from Dexco, Solprene™ from Enichem Elastomers and Stereon™ from Firestone Tire &, Rubber Co. Amorphous polyolefins or amorphous polyalphaolefins (APAO) are homopolymers, copolymers, and teipolymers of C2-C8 alphaolefins. These inaterials are typically polymerised by means of processes, which employ Zaegler-Natta catalysts resulting in a relatively broad molecular weight distribution. Commercially available amorphous polyalphaolefins include RextacTM and REXFlex™ propylene based homopolymers, ethylene-propylene copolymers and butene-propylene copolymers available from Rexene (Dallas, TX) as well as Vestoplast alpha-olefin copolymers available from Huls (Piscataway, NJ). Metalloceae polyolefins are homogeneous linear and substantially linear ethylene polymers prepared using single-site or metallocene catalysts. Homogeneous ethylene polymrars are characterized as having a narrow molecular weight distribution and a uniform short-chain branching distributian. hi the case of substantially linear ethylene polymers, such homogeneous ethylene polymers are further characterized as having long chain branching. Substantially linear ethylene polymers are commercially available from The Dow Chemical Company as Affinity polyolefin plastomers, which are produced using Dow's InsiteTM technology, whereas homogeneous linear ethylene polymers are available from Exxon Chemical Company under the tradename ExactTM Homogeneous linear and substantially linear ethylene polymers having a relatively low density, ranging from about 0.855 to about 0.885, and a relatively low melt index, for example less than about 50 g/l0min arc most preferred, particularly for creating elastomeric fibers, films and adhesive compositions that swell upon exposure to water. The term 'interpolymer' is used herein to indicate a copolymer, terpolymer, or higher coder polymer. That is, at least one other comonomer is polymerized with ethylene to make the interpolymer. Interpolymers of, ethylene are those polymers having at least one comonomer selected from the group consisting of vinyl esters of a saturated carboxylic add wherein the acid moiety has up to 4 carbon atoms, unsaturated mono- or dicarboxylic acids of 3 to 5 carbon atoms, a salt of the unsaturated acid, esters of the unsaturated acid derived from an alcohol having 1 to 8 carbon atoms, and mixtures thereof. If employed uncompounded, the ethylene to unsaturated carboxylic comonomer weight ratio is preferably greater than about 3:1, more preferably about 2:1. Hence, the comonomer concentration is preferably greater than 30 wt-%, more preferably greater than 33 wt-% and most preferably greater than 35 wt-%, with respect to the total weight of the ethylene interpolymer. The melt index of the interpolymers of ethylene may range from about 50 to about 2000, preferably from about 100 to 1500, more preferably from about 200 to 1200, and most preferably from about 400 to 1200 g/10 min. When employing a polymer having too low of a melt index uncompounded, the strength of the polymer tends to constrain the swelling of the particles of superabsorbent material. Suitable ethylene/unsaturated carboxylic acid, salt and ester interpolymers include ethylene/vinyl acetate (EVA) ethylene/acrylic acid (EEA) and its ionomers; ethylene/methacrylic acid and its ionomers; ethylene/methyl acrylate (EMA); ethylene/ethyl acrylate; ethylene/t-butyl acrylate (EnBA); as wel as various derivatives thereof that incorporate two or more comonomers. Other suitable thermoplastic polymers that may be emloyed include polylactide, caprolactone polymers, and poly (hydroryr-butyrate/bydroxyvalerate), certain polyvinyl alcohols, biodegradable copolyesters such as Eastman Copolyester 14766 (Eastman), linear saturated polyesters such as Dynapol or Dynacoll polymers from Huls, poly (ethylene oxide) polyether amide and polyester ether block copolymers available from Atochem (PebaxTM, e.g. Pebax MV 3000) or Hoechst Celanese (Rite-flexTM respectively, and polyamide polymers such as those available from Union Camp (Unirez™) or Huls (Vestamelt™) or EMS-Chemie (Griltex™). Other suitable thermoplastic polymers are c.g. polyuretbanes, poly-ether-amides block copolymers, polyethylene-acrylic acid and polyethylene-methactylic acid copolymers, polyethylene oxide and its copolymers, ethylene acrylic esters and ethylene methacrylic esters copolymers, polylactide and copolymers, polyamides, polyesters and copolyesters, polyester block copolymers, sulfonated polyesters, poly-ether-ester block copolymers, poly-ether-ester-anride block cqpolymers. ionomers, polyethylene-vinyl acetate with a vinyl acetate content of at least 28% by wdght, polyvinyl alcohol and its copolymers, polyvinyl ethers and their copolymers, poly-2-ethyl-oxazoline and derivatives, polyvinyl pyrrolidone and its copolymers, thermolastic cellulose derivatives, poly-caprolactone and copolymers, poly glycolide. polyglycolic acid and copolymers, polylactic acid and copolymers, polyureas, polyethylene, polyprolene, or mixtures thereof. Particularly suitable preferred thermoplastic polymers are selected from themopastic poly-ether-amide block copolymers (e.g. Pebax"™). thermoplastic poly-ether-ester-amide block copolymers, tharmorplastic polyester block copolymers (e.g. HytrelTM, e.g. Hytrel 8171), thermoplastic polyurethanes (e.g. Estane"™), or mixtures thereof . The polymeric base materials for use herein preferably furthermore comprise from 5% to 90%, preferably 10% to 85%, more preferably from 15% to 70%, most preferably from 30% to 65% by weight of suitable comatible plasticizers. Suitable 'plasticizers' for use in the present invention generally will include any conventional plasticizers which decrease hardness and modulus, enhance pressure sensitive tack and reduce melt and solution viscosity. It is prefatred that the plasticizer be water soluble or water dispersible or alternatively be a wax-like substance such as polyethylene or polypropylene glycol, glycerin, glycerol and its esters, butylene glycol or sorbitol. Other plasticizers suitable for use in the present invention are esters of sucrose; phthalate plasticizers such as dioctyl phthalate and butyl benzyl phthalate (e. g., Santicizer 160 from Monsanto); benzoate plasticizers such as 1,4- cyclohexane dimethanol dibenzoate (e.g., Benzoflez 352 from Velsicol), diethylene glycol/dipropylene glycol dibenzoate (e.g., Benzoflez 50 from Velsicol), and diethylene glycol dibenzoate where the mole fraction of hydroxyl groups which have been esterified ranges from 0.5 to 0.95 (eg., Benzoflex 2-45 High Hydroxyl also from Velsicol); phosphite plasticizers such as t-butyl diphenyl phosphate (e.g., Santicizer 154 from Monsanto); adipates; sebacates; epoxidized vegetal oils; polymerised vegetal oils; polyols; phthalates; liquid polyesters such as Dynacol 720 from Huls; glycolates; p-toluene sulfonamide and derivatives; glycols and polyglycols and their derivatives; sorbitan esters; phosphates; monocarboxylic fatty acids (C8-C22) and their derivatives; liquid rosin derivatives having Ring and Ball hydrocarbon oils which are low in aromatic content and which are paraffinic or naphthenic in character and mixtures thereof. Plasticizer oils are preferably low in volatility, transparent and have as little color and odor as possible. An example of a preferred plastizer is CarbowaxTM polyethylene glycol from Union Carbide. Other preferred plasticizers are PEG 400 and PEG 1500 from Aldridi. The use of plasticizers in this invention also cantemplates the use of olefin oligomers, low molecular weight polymers, vegetable oils and their derivatives and similar plasticizing liquids. According to a preferred embodiment of the present invention particularly preferred plasticizers to be used herein are hydrophilic plasticizers such as acids, esters, amides, alcohols, polyalcohols, or mixtures thereeof, among which even more preferred are citric acid esters, tartaric acid esters, glycerol and its esters, sorbitol, glycolates, and mixtures thereof, as disclosed in our application WO 99/64505. Said preferred hydrophilic plasticizers have a particularly high polar character and provide the further advantage that they do not impair, and possibly can even enhance, the moisture vapour permeability of the resulting layer or film formed from the polymeric base material and thus the liquid absorbent thermoplastic composition of the present invention comprising said preferred plasticizer or blend of plasticizers, when compared to a corresponding film or layer formed from an liquid absorbent thermoplastic composition comprising the same components, but without the plasticizer or plasticizers. These particularly preferred hydrophilic plasticizers or blends of hydrophilic plasticizers can of course also adjust the viscosity of the polymeric base material and thus the liquid absorbent thomoplastic composition according to the present invention. Thus, the viscosity can be fine-tuned to the preferred values disclosed infra in order to make said comosition processable. Plasticizers selected among those described in European patent application EP 1,193,289 can also be used herein. Said plasticizers can be selected from the group consisting of esters of phosphoric acid; esters of benzoic, phthalic and trimellitic acids; esters of polycarboxylic oxy-acids; sulphonamides and their derivatives such as sulphonamide-formaldehyde resins; sulfones; esters of poly-valent alcohols; lactides; glycolides; lactones; lactams. Said plasticizers are capable of also providing the polymeric base material and thus the liquid absorbent thermoplastic composition with a certain degree of tackiness. The polymeric base material for use in the liquid absorbent thermoplastic composition of the present invention optionally also comprises from 0% to 100%, preferably 1% to 30%, more preferably from 5% to 20%, most preferably from 8% to 12% by weight of tackifying resins. As used herein, the term 'tackifying resin' means any of the liquid absorbent thermoplastic compositions described below that are useful to impart tack to the polymeric base material. ASTM D1878-61T defines tack as "the property of a material which enables it to form a bond of measurable strength immediately on contact with another surface", Tackifying resins comprise resins derived from renewable resources such as rosin derivatives including wood rosin, tall oil and gum rosin as well as rosin esters, natural and synthetic terpenes and derivatives of such. Aliphatic, aromatic or mixed aliphaticaromatic petroleum based tackifiors are also useful in the invention. Representative examples of useful hydrocarbon resins include alpha-methyl styrene resins, branched and unbranched C5 resins, C9 resins and C10 lesins, as well as styrenic and hydrogenated modifications of suck Tacldfying resins range from being a liquid at 37°C to having a ring and ball softening point of about 135°C. Suitable tacldfying resins for use herein include natural and modified resins; glycerol and pentaerythritol esters of natural and modified resins; polyterpene resins; copolymers and terpolymers of natural tetpenes; phenolic modified terpene resins and the hydrogenated derivatives thereof, aliphatic petroleum resms and the hydrogenated derivatives thereof; aromatic petroleum resin and the hydrogenated derivatives thereof; and aliphatic or aromatic petroleum resms and the hydrogenated derivatives thereof, and combinations thereof Commercial examples of these types of resins include Foral™ hydrogenated rosm ester, Staybelite™ hydrogenated modified rosin, Polypale™ polymerized rosin, Permalyn™ rosin ester, Pentalyn™ rosin ester, Adtac™ oil extended hydrocarbon resin, Piccopale™ aromatic hydrocarbon, Piccotac™, Hercotac™ aromatic modified aliphatic hydrocarbon, Regahez™ cycloaliphatic resins, or Piccolyte™ from Hercules, Eselementz™ from Exxon Chemical aliphatic hydrocarbon and cycloaliphatic resins, Wingtack™ from Goodyear Tire & Rubber Co. synthetic polytetpene resins including aromatic modified versions, Arkon™ partially and fully hydrogenated aromatic resios from Axakawa Chemicals, ZonatacTM styrenated terpene resm, Zonarez™ rosin ester and Zonester™ rosin ester from Arizona Chemical and Nevtac™ aromatic modified aliphatic hydrocarbon from Neville Chemical Company. The polymeric base material for use in the liquid absorbent thermoplastic composition of the present invention optionally also comprises from 0.1% to 10%, preferably 0.2% to 5%, more preferably from 05% to 2%, most preferably from 0.75% to 1.5% by weight of anti-oxidants. Suitable 'anti-oxidants' for use in the present invention include any conventional anti-oxidants, and are preferably hindered phenols such as for example Ethanox 330™ l,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl) benzene which is commercially available from the Ethyl Corporation. Other examples for suitable anti-oxidants are hindered phenolics (e. g., Irganox 1010, Irganox 1076, Irganox B 225). The polymeric base material for use in the liquid absorbent thermoplastic composition of the presait invention optionally also composes surfactants. Suitable 'surfactants' for use herein are additives that reduce the surface tension and/or contact angle of the polymeric base material Surfactants are useful in amounts ranging from about 0 % to about 25 % by weight and preferably from about 5 % to about 15 % by weight, with respect to the total weight of the polymeric base material. Suitable surfactants include nonionic, anionic, and silicone surfactants. Exemplaty nonionic surfactants are: Ethoxylates of (i) C1-C18, preferred C8-C9 alkyl or dialkyl phenols, such as those sold under the tradenames Macol DNP-10, available from PPG Industries, Chimee, HI., a 10 mole ethoxylate of dinonyl phenol, and Triton X-100, available from Union Carbide, a 10 mole ethoxylate of octyl phenol ; (ii) alkyl C8-C60 monoalcohols, such as those sold under the tradenames Surfonic L-12-8, an 8 mole ethoxylate of dodecanol, available from Huntsman Chemical Co., and Unithox 480, a 38 mole ethoxylate crystalline surfactant available from Petrolite Specialty Polymers Group, Tulsa, Okla.; and (iii) propylene oxide polymers, such as those sold under the tradename Pluronic, which are ethylene oxide/propylene oxide block copolymers having a Ma of 200 to 3000, available from BASF; and benzoates formed by partial condensation of benzoic add with hydrophilic di or mono-ols having less than 1000 Mo, such as the product of condensing about three equivalents of benzoic acid with four equivalent of diethylene glycol, commercially available as XP 1010 from Velsicol Chemical. A preferred nonionic surfactant blend is Atmer 685, avalable from ICI Surfactants (Wilmington, DE). Suitable anionic surfactants are: C8-C60 alkyl ethoxylate sulfonates, (CH3-(CH2)11-14 (O-CH2- CH)3-SO3 Na+, such as, Avenel S30, available from PPG Industries; alkyl C8-C60 sulfonates like sodium dodecyl sulfate (SDS), such as Rbodapon UB (C12-SO3 Na+) available from Rhone Poulenc; and alkyl/aromatic sulfonates, such as those sold under the tradename Calsoft Suitable silicone surfactants are ethoxylates or propoxylates of polydimethyl siloxane, having a number average molecular weight of 500 to 10,000, preferably 600 to 6000, such as are sold under the tradenames Silwet L-77, L-7605, and L-7500 availablefrom OSi Specialties, Danbury, Conn.; and product 193 from Dow Commg. The preferred surfactants are those with lower molecular weight because these have increased compatibility in the polymeric base material. The maximum acceptable molecular weight depends on the type of surfactant and the other ingredients in the polymeric base material and thus the liquid absorbent thermoplastic composition of the present invention. Other optional components of the polymeric base material for use herein include anti-ultraviolets, dyes (as long as they do not compromise the transparency of the composition), antibacterials, odour adsorbing materials, perfumes, pharmaceuticals, and mixtures thereof, which may be present within the liquid absorbent thermoplastic compositions at a level of up to 10% by weight of the composition. The liquid absorbent thennoplastic composition of the present invention is preferably a hot-melt adhesive, ie. the polymeric base material compositiona hot-melt adhesive, which is capable of absorbing aqueous liquids. Such preferred liquid absorbent thermoplastic compositions comprise (by weight): a) from about 5% to about 99% of a polymeric base material, comprising a') from about 10% to about 50% of a block copolymer, a") from about 0% to about 50% of a tackifying resin; and b) from about 1% to about 95% of particles of superabsorbent material having substantially angle-lacking shapes and having an average particle diameter in dry state of from 0.1µm to 500µm. As the preferred liquid absorbent thermoplastic composition of the present invention is substantially transparent, it is beneficial that all its components are substantially transparent as well. However, it is also possible that componnts, which are not substantially transparent, can result in a substantially transparent liquid absorbent thennoplastic composition once mixed, e.g. by interaction, such as chemical reaction, with other components of the absorbent composition. Another preferred embodiment of the preferred substantially transparent liquid absorbent thermoplastic composition of the present invention is the following hot-melt adhesive composition, comprising (by weight) a) from about 5% to about 99% of a polymeric base material, comprising a') from about 10% to about 50% block copolymer, a') from about 0% to about 50% tackifying resin, a'") from about 10% to about 80% plasticizer, a" ") from about 0% to about 2% antioxidant; and b) from about 1% to about 95% of particles of superabsorbent material having substantially angle-lacking shapes and having a an average particle diameter in dry state of from 0.1 µm to 500 µm. Highly preferred thermoplastic polymeric base materials for use in the liquid absorbent thermoplastic composition described herein before are those having a water absorption capacity of at least 30%, preferably more than 40%, more preferably more than 60% and most preferably more than 90%, when roeasured according to the Water Absorption Test described herein in accordance with ASTM D 570-81, on a 200 µm thick filn. The intrinsic absorbency of the polymeric base material/matrix allows for a more effective diflusion of the body fluid within the matrix and, consequently, for a better spreading of the body fluid, which can reach a greater number of absorbent material particles, which in turn give rise to a better utilization of the absorbent material. Highly preferred liquid absorbent thermoplastic composition described herein before are those having inproved mechanical properties, such as good integrity in wet state thanks to good internal cohesion and hence having a tensile strength in wet state which is at least 20%, preferably at least 40%, and more preferably at least 60% of the tensile strength of said composition in dry state. Said tensile strengths are evaluated according to the Tensile Strength Test described herein. It should be appreciated that by selecting a thermoplastic base material in the liquid absorbant thermoplastic composition herein having a higher value of water absorption, the absorbent composition will have better liquid absorption/handling characteristics, while not comprising on tensile strangth in wet state. Indeed such absorbent composition will remain substantially intact and have sufficient tensile strength for its intended use, also upon liquid absorption. Indeed the highly preferred liquid absorbent thermoplastic composition for use herein offer improved mechanical and absorbent properties. Without to be bound by theory it is believed that the intrinsic absorbency of the matrix allows the body fluid to be acquired and diffused within the matrix thus permitting fluid contact with the absorbent material contained in the matrix and their swelling, without the necessity of having a matrix of low cohesive strength but with a matrix, which remains substantially intact and having sufficient strength upon fluid absorption. The absorbent in particle form is blended with the polymeric base material in any known manner to provide the liquid absorbent thermoplastic composition for use herein. For example, by first melting the thermoplastic polymeric base material and then by adding and mixing the required amount of absorbent material particles. Suitable adhesive processing equipments can be used such as a melt mixer or extruder. Preferably the liquid absorbing thermoplastic composition for use herein are formulated to have hot melt adhesive characteristics so that they can be applied utilizing any known method used for applying hot melt adhesives. At least at the coating temperature, since the liquid absorbent thermoplastic composition comprises thermoplastic polymeric base materials, it can exhibit adhesive prroperties on a supportive substrate in order to form a composite structure such that no additional adhesive is required to achieve a permanent attachment between the absorbent dement, which is provided partially or preferably completely by the liquid absorbent thermoplastic composition, and the substrate. However, while hot melt techniques are preferred, any other known method for processing thermoplastic composition can be used for processing the absorbent composition in any known form/pattern. Also, any known method for spraying, printing, dotting, coating or foaming thermoplastic composition can be used as well as extrusion or laminatian processes. Particularly suitable methods for applying the liquid absorbent thermoplastic composition to a substrate are gravure printing or slot coating. Both methods are particularly suitable for discontinuous application of the thermoplastic composition described herein onto a substrate. The gravure print unit or slot coater applies the thermoplastic composition in the desired pattern onto a substrate. In its broadest embodiment the present invention also encompasses the use of a substantially transparent liquid absorbent thermoplastic composition containing particles of superabsorbent material having a substantially angle-lacking shape, as a loading indicatar e.g. in disposable absorbent articles. Therefore, one layer of the article has to comprise the composition of the present invention in a visually noticeable manner prefrably as a film. A possible embodiment could be provided in that the composition of the present invention is provided underlying the topsheet of an absorbent article, preferably as a film, so that said composition is visible to the user through the topsheet. The topsheet can be either transparent or can alternatively have apertures through which said film is visible. The functionality of such a loading indicator is as follows: Due to the swelling of the particles of superabsorbent material, when subjected to aqueous fluids, &ere is a visually-noticeable difference in the diffraction and/or absorption of light trespassing through the composition of the present invention between its wet and its dry state, in particular the composition is becoming more opaque when wet This visually recognizable increase in opaqueness of the composition of the present invention when wetted can be used as a loading indicator for the wearer of such an article. In a preferred embodiment the liquid absorbent thermoplastic composition is substantially transparent The preferred substantially transparent liquid absorbent thermoplastic composition of the present invention is suggested to be used in the field of absorbent articles, preferably transparent absorbent articles. In particular it is suggested to use the substantially transparent liquid absorbent thermoplastic composition for the construction of the absorbent core of substantially transparent absorbent articles. Such substantially transpateant absorbent articles have at least one region, which is transparent through its thickness. Preferably, the entire absorbent article is transparent through its thickness. In a preferred embodiment, a transparent absorbent article has a transparent topsheet, a transparent backsheet and a transparent absorbent core comprising the liquid absorbent thermoplastic composition of the present invention. Suitable topsheets are compliant, flexible, soft feelmg and non-initating to the weater's skin. The topsheet can be made from a nonwoven or woven material or a film that has been rendered liquid-pervious by aperturing. In general the backsbeet is compliant, flexible and soft feeling. The backsheet prevents the body fluids absorbed and contained in the absorbent core from wetting clothes that contact the absorbing article, such as undergarments. Preferably the backsheet is impervious to liquids (e.g., menses, sweat and/or urine). It can be manufactured from a thin plastic film, although other flexible liquid inpervious materials can also be used. As used herein, the term "flexible" refers to materials that are compliant and will readily conform to the general shape and contours of the human body. The backsheet preferably also can have elastic charax;teristics allowing it to stretch in one or two directions. Furthermore it is preferred that the backsheet for use herein is breathable, x.e. being pervious to gases / vapour while being impervious to liquids. The topsheet and the backsheet can be completely transparent or can be provided only with regions of transparency. Suitable materials for the topsheet or backsheet for use herein can be found e.g. in EP-A-1,138,293. An example for suitable topsheet materials is an apertured polyethylene formed film, e.g. transparent CPM DH TM available from BP Chemicals. An example for suitable backsheet materials is a nonwoven without pigment, e.g. code W16Fio, basis weight 16 g/m2, available from BBA Corovin. The liquid absorbent thermoplastic composition of the present invention can be used in absorbent articles, preferably in substantially transparent ones, as the absorbent core. In a isefened embodiment, the liquid absorbent thamoplastic composition is used as the sole material comprising the core, being directiy adjacent to a substantially transparent topsheet and a substabtually transparent backsheet Alternatively, the liquid absorbent thermoplastic composition can comprise optional components as part of the abscabent core. Such optional components are fluid distributian layers, optional fibrous layers, reinforcing scrims or odour control materials for counteracting malodours. If present, these materials are chosen to be transparent as well. Suitable materials for those optional components are disclosed in EP-A-1,138^93. Absorbent articles according to a preferred embodiment of the present invention are constructed like conventional articles with the exception that the conventional means for johiing portions of material together must be carefully considered to ensure that the objective of creating a transparent region is not lost For instance the adhesive used to join the topsheet to the backsheet in the region outside the absorbent core should either be transparent or it should be eliminated and be replaced by e.g. crimping. The transparency as indicated above can be used beneficially in the context of sanitary napkins., panty liners and sweat pads (underarm or collar). A new product design, which is a sub-form of a sanitary napkin or panty liner form, namely thong shaped sanitary napkins or panty liners, so called thong liners, are particularly susceptible to the present invention. The thong liner design is such that it provides the sanitary napkin or panty liner with a shape such that it can be worn in thong slips, G-stcing undergarments or string panties, hence the thong shape is fundamentally triangular or trapezoidal. In general, all typically used components in absorbent products can also be comprised in the preferred absorbent articles according to the present invention as long as the absorbent article comprises at least one region of transparency. Most preferred, the absorbent articles will comprise a fastening adhesive for attachment The design of the fastening adhesive must be selected such that it does not interfeare with the desired transparency, but transparent adhesives will ensure that In the case of sanitary napkins, panty liners or thong liners, a so called panty fastening adhesive is preferred to be present on the backsheet for attachment to an undergarment. However, for sweat pads, e.g. underarm sweat pads, either attachment to an adjacent garment or attachment to the skin of the wearer directly can also be considered. Of course, such direct skin attachment, which is conventionally provided by water gel, hydrogel or oil gel based body adhesives can also be used in sanitary napkins or body liners (in contrast to panty liners). Test procedures: a") Transparency Test General Definition 'Optically transparent' as used herein means peamitting the passage of light radiation. 'Optically transparent medium' as used herein means a medium, which has the property of transmitting rays of lights in such a way that the human eye may see through the medium distinctly. In general, transparency is the ability of a material to transmit light through itself and, consequently, by the transparency it is possible to see e.g. objects or colours or printed or written text through such material According to the above terminology transparency of a product is defined by: 1. having the property of transmitting rays of light in such a way that written or printed text/characters and colours located opposite the transparent product can be clearly viewed by the human eye. and/or 2. having the property of transmitting rays of light in such a way that the human eye may see through the product. One of the main advantages delivered by a transparent product is that its presence (colour) is less recognizable by the human eye, such that, in case of absorbent articles for feminine hygiene, the colour of the undergarment (or other clothing) is recognizable (visual discreteness, no product awareness) ' Colours can be measured according to the CIELAB colour system (CIE 1976 L*a*b*). The CIELAB colour space can be visualized as a three dimensional space, where every colour can be uniquely located. The location of any colour in the space is deteixoined by its colour coordinates; L*. a*, b*. In other words, all colours that are perceived by the human eye are converted into a numerical code. When a colour is defined according to this system L* represents lightness (0 = black, 100 = white), a* and b* independently each represent a two colour axis, a* representing the axis red/green C+a = red, -a = green), while b* represents the axis yeEow/blue (+b = yellow, -b = blue). AE represents graphically the distance between two colours. In this case, E represents the distance between the reference colour and the centre of the sphere of the 3d model (L* = 50, a* = 0, b* = 0). E = t(L)2 + (a) 2 + (b) 2)]2 The ability to see a colour through a matenal (or product) is measured as an index of transparency. If a material is 100% transparent, it is possible to measure the same L*, a*, b* and AE value for the above colour alone and through the material. As a reference the colour white is used. The closer the colour is to the white reference (when both are viewed through the material/product) the less transparent that material (or product) will be considered. Colour Transparencv Methodology Colour can measured using the colorimeter MINOLTA model CR-300 instrument (available from the Minolta Company, Japan) which provides the coordinates L*. a*, b* and from which the AE value can be determined. The standard colours used in this measuremait are the primary colours Cyan, Magenta and Yellow references of PANTONE Colour Specifier 747XR and the white calibration reference plate of the colorimeter instrument. The colour grade coordinate values for the material to be tested for each of the colour references Cyan, Magenta and Yellow is detetermined by placing the material or product on the colour specific reference and taking a reading from the colcaimeter and calculating AE. For each of the reference colours (ic) the E value is recalculated by setting the scale such that En: result, referred to as E is zero (i.e. 100% transparent) and that Ewhie with respect to the reference colour is referred to as E*, which is 62.2 for example and represents 0% transparency. This can be represented by the formulae below: (Formula Removed) The E value for the product/transparent region of the product for each reference colour (Ep) is then calculated using the following formula: (Formula Removed) Transparency of the product for each reference colour is determined according to the formula: (Table Removed) The total transparency is the average value of the transparency for each reference colour, i.e. (Formula Removed) An example on how to cany out the above-outlined test is shown in Figure 2. b") Viscosity Test The instrument used to perform the viscosity tests was a Reologica STRESSTECH ETC-3 Cell with a tool geometry as follows: cone plate 40 mm, angle 3 degrees. The temperature was set to 150°C and the shear rate to 10 s'. The procedure used is as follows: • Insert the cone plate tool and set the temperature at 150 "C. Wait 15 min to reach the right temperature of the tooL Make the zero gap by the autozero function. Performing the sample use the autogap function, applying max. 1N of stress. After the sampling wait 120 seconds as equilibrium time. Integration time 30 seconds. Chose the value of viscosity measured at 50 sec. c) Water Absorption Test for the polymerio base material The determination of the water absorption of the polymeric base material is conducted according to the staadard test method ASTM D 570-81 with the following conditions: The measurement of water absorption for thermoplastic polymeric compositions is made on the material in form of a film sample 76.2 mm long by 25.4 mm wide by 0.2 mm thick. For all materials a 24 hours immersion in distilled water at 23°C was chosen and the percentage of water absorbed was reported in accordance with the ASTM D 570-81 standard. d) Water Absorption Test for the liquid absorbent thermoplastic composition The total liquid absorption capacity of the liquid absorbent thermoplastic composition is determined as follows: Principle: The sample is weighed and submerged in the test solution for 10 minutes and afterwards weighted to determine the total absorption capacity. Preparation of saline solution: 9 g ± 0.1 g NaCl is added to deionised water to give a total mass of 1000 g ± 0.1 g (saline solution 0.9%) and stinted until dissolved. Apparatus and materials: 1. Bag (100 X 50 mm) heat-sealable polyester mesh, folded and beat sealed on two (longer) of the three open sides so the inside edges of the seals are about 3 to 5 mm from the edge of the bag. Polyester mesh characteristic: Mass per unit area: 48 g/m2. Thickness: 60 µm Holes dimension: 18 µm Open area: 13 %, Yarn diameter 31 µm Number of yam: 200/cra Suggested supplier Saatitech; Reference material: PES 18/13 2. Heat sealer capable of bonding polyester. 3. Analytical balance, capable of measuring a mass of 100 g to an accuracy of ± 0.001 g. 4 Weighting silicon paper. 5. Timer. 6. Beaker capable of containing 1 litre of solution. 7. Spatula. 8. Tweezers. Sample preparation Starting from an absorbent article the hquid absorbent thermoplastic composition can be isolated with known means in order to be tested. Typically, in an absorbent article the topsheet is removed from the backsheet and both are separated from any additional layers if present The Hquid absorbent themoplastic composition is removed from its substrate layer, e.g. by scraping with a spatula. The liquid absorbent thermoplastic composition will be used to prepare samples as mentioned below with known means. For example, the thermoplastic composition can be melted, or dissolved with a suitable solvent The recovered composition must be kept in a closed container to avoid dust contamination and be allowed to equilibrate to the temperature to run the test The test conditions are 23 °C ± 2 °C and 50 ± 10 % relative humidity. Procedure 1. Weigh 0.200 g ± 0.005 g of the Uquid absorbent thamoplastic composition and record the mass (Wd). 2. Prepare a sufficient number of bags (i.e., 6) to run the required replicates. 3. Place each single test portion of 0.200 g ± 0.005 g of the hquid absorbent thermoplastic composition into each single bag and seal the bags opened side. 4. Prepare two blank bags (i.e. without any composition) and test alongside ihe bags containing the thermoplastic composition. 5. Fill the beaker with 0.9 % saline solution. 6. Submerge the bags in the saline solution. Eliminate entrapped air bubbles by manipulation of the bag. 7. After 10 minutes ( ± 10 seconds), remove the bags from saline solution and hang them freely to drain vertically till no liquid is dripping from them. 8. Weigh each single bag recording the masses of the two blanks (Wb) 1 and 2 and the masses of bags containing the absorbent composition (Ww) 1,2,.....n. calculation and results Calculate the average of the two wet blank bags masses after absorption Wb = (Wbl+Wb2)/2 For each sample calculate: Abs (g/g) = (Ww - Wb - Wd) / Wd Where- Wd = dry test portion mass in g. Wb = average of 2 blank bag masses (after absorption) in g. Ww = mass of wet bag containing liquid absorbent thermoplastic composition in g. e) Thickness measurement The thickness of a film of the liquid absorbent thermoplastic composition of the present invention should always be measured at the thickest possible place. The thickness is measured with a micrometer gauge having a range of 0 to 30 mm and capable of plus minus 0.5 mm tolerance. The gauge must not be spnng-loaded and should have a foot moving downwards imder gravity The micrometer foot has a diameter of 40 mm and is loaded with 80 gram weight The measurement is taken between 5 and 10 seconds after the foot has been lowed to come into contact with the absorbent article. Measurements should be taken often enough to allow statistical analysis to determiae average thickness within a sigma of plus minus 0.1 mm. A detailed description of the thickness measurement can also be found in US patent 5,009,653. f) Tensile Strength Test The test measures the mechanical resistance of a samples of material as tensile strength at break, according to the standard test method ASTM D 412-92, under the following conditions. The test is performed on samples made of the liquid absorbent thermoplastic composition of the present invention having a length of 130 mm, a width of 25.4 mm, and a thickness of 2 mm, and being continuous, obtained with any suitable method, for example by pouring the Uquid abscobent thermoplastic composition in molten state at a suitable temparture e.g. 180°C for the composition of Examples 2 or 3, mto a metallic pan lined with release paper in a continuous layer having a thickness of 2 mm, and then after cooling cutting from tins layer the samples of the desired dimensions. The test is performed on samples made of the same composition both in dry and in wet state. In order to prepare the samples in wet state a samples is placed in a container of a saline solution (e.g. 0.9% NaQ distilled water solution) maintained at a temperature of 23 ± TC, and shall rest entirely immersed for ten minutes. At the end of ten minotes, the samples shall be removed from the water, all surface water wiped off with a dry cloth, and tested for wet tensile strength as provided in the standard test method. s.) Alternative sample preparation for all test herein when starting from an absorbait article When starting from an article comprising the liquid absorbent thermoplastic composition, for example a disposable absorbent article with the liquid absorbent thermoplastic composition coated onto a substrate, the liquid absorbent thermoplastic composition can be isolated with known means in order to be tested. Typically, in a disposable absorbent article the topsheet is removed from the backsheet and both are separated from any additional layers if present The liquid absorbent thermoplastic composition is removed from its substrate layer, e.g. by scraping with a spatula. The recovered liquid absorbent thermoplastic composition will be used to prepare samples as mentioned above with known means. For example, the liquid absorbent thermoplastic composition can be melted, or dissolved with a suitable solvent Particles of superabsorbent material can be also separated from the polymeric base material, in order to isolate the polymeric base material, as it is known in the art, for example by suitably sieving or filtaing from the molten state, or preferably from the solution. Examples: The particle size of the Aqua Keep lOSH-NF particles used m all the following examles was between 20 and 30 /im, the particles were approximately spherical beads. 1.) Examples for the liquid absorbent thermoplastic composition of the present invention are: An example for the liquid absorbent thermoplastic composition of the present invention is the following mixture, forming a hot-melt adhesive: 18% Estane T5410 from Noveon 17% PEG E400 from Dow Chemical 1 % Irganox B 225 from Ciba Speciality Chemicals 19% CROO (fonner PM17) from Savare 45% Aquakeep 10 SH-NF from Sunritomo-Seika. Estane T5410 is a hydrophilic polyurethane thermoplastic polymer, PEG E400 is a polyethylene glycol (plasticizer, MW about 400), Irganox B 225 an anti oxidant and CROC is commercially available hotmelt adhesive. Example 2 A thermoplastic polyether-amide block copolymer available from Atofina (France) under the trade name Pebax MV 3000 is compounded with polyethylene glycol PEG 400 (plasticiser, MW about 400), Sodium Dodecyl Sulphate (SDS), both available from Aldrich Co., and frganox B 225 (anti oxidant agent) available from Ciba-Geigy. The formulation in percent by weight has the following composition, and constitutes the thermoplastic polymeric base material: 28.6% Pebax MV 3000 68.6% PEG 400 1.4% SDS 1.4% IrganoxB225 The thermoplastic polymeric base material has a water absorption of 43%, value measured according to the Water Absorption Test described herein. The polymeric base material is formed into a film to be used in the Water Absorption Test by melt coating the thermoplastic base material at a temperature of 180°C onto a release paper to obtain a film having the prescribed thickness of 2(X) µm After cooliug at room temperature the film is separated from the release paper. A superabsorbent material in particle form, sold under the trade name Aqua Keep lOSH-NF by Sumitomo Seika Chemical (Japan), is added to the thermoplastic polymeric base material while maintained at a temperature of 180°C and uniformly dispersed, in an amount corresponding to 42.9% by weight of the above thermoplastic polymeric base material. This example of the liquid absorbent thermoplastic composition has the following final composition by weight: 20% PebaxMVSOOO 48% PEG 400 30% Aqua Keep lOSH-NF 1% SDS 1% IrganoxB225 Example 3 A thertnoplastic polyether-ester block copolymer available from Du Pont (USA) under the trade name Hytrel 8171 is compounded with polyethylene glycol PEG 400 (plasticiser, MW about 400), polyethylene glycol PEG 1500 (plasticiser, MW about 1500), both available from Aldrich Co , and Irganox B 225 (anti oxidant agent) available from Ciba-Geigy. The fonnnlation in percent by weight has the following composition. and constitutes an alternative thermoplastic polymeric base material: (Table Removed) measured according to the Water Absorption Test described herein. The thermoplastic base material is formed into a film to be used in the Water absorption Test by melt coating the thermoplastic base material at a temperature of 180°C onto a release paper to obtain a film having the prescribed thickness of 200 µm. After cooling at room temperature the film is separated from the release paper. A superabsorbent material in particle form sold under the trade name Aqua Keep 10SH-NF by Sumitomo Seika Chemical (Japan) is added to the thermoplastic polymeric base material while maintained at a temperature of 180°C and uniformly dispersed, in an amount corresponding to 42.9% by weight of the thermoplastic polymeric base material. As another illustrative example of the present invention, the resulting liquid absorbent thermoplastic composition has the following final composition by weight 20% Hytrel8171 15% EBG400 34% PEG 1500 30% Aqua Keep lOSH-NF 1% IrganoxB225 All these exemplary compositions (Examples 1 to 3) respectively have a tensile strength in wet state, which is at least 35% of the tensile strength of the composition in dry state, when evaluated according to the Tensile strength test described herein. All these exemplary compositions (Examples 1 to 3) respectively have a total absorption capacity towards saline solution (0.9%) of more than 5 grams per gram when measured according to test described herein before. 2) Exemplary absorbent articles according to the present invention are described herein after: Example 4 A panty liner comprises an apertured polyethylene formed film topsheet (Transparent TS3 coded X28278 available from Tredegar), a spiral layer of adhesive (D3151 available from Fuller), a Secondary Topsheet nonwoven material (carded bico Sawabond 4314 available from Sandler), an adhesive absorbent core consisting of the composition of Example 2, a plastic polyethylene film backsheet without pigment (code 14/18020, available from RKW) and panty fastening adhesive (HL1461 available from Fuller). The topsheet, the secondary topsheet, the absorbent core and the backsheet are substantially coextensive with each other and are attached to each other along the outer edge of the so-formed panty liner by heat bonding. Examples A sanitary napkin comprises an apertured film topsheet (CPM RIS coded 1035025 available from Tredegar) as the uppermost layer, a 40 g/m2 BICO thermalbonded carded nonwoven secondary topsheet from Sandler (coded Sawabond 4313) underneath the topsheet and a polyethylene backsheet from RKW (coded RKPA) as the lowest layer. Between the secondary topsheet and the backsheet the liquid absorbent thermoplastic composition of example 2 is applied in stripes, which are substantially parallel to the longitudinal centreline of the so-fonned sanitary napkin, thus forming the absorbent core. The topsheet, the secondary topsheet, the absorbent core and the backsheet are substantially coextaisive with each other and are attached to each other along the outer edge of the so-formed napkm by heat bonding. On the outer surface of the backsheet a layer of the panty fastening adhesive LA 204 from Savare was applied. Example 6 A sanitary napkin as in Example 5, said napkin comprising in addition to the elements mentioned in Example 5 a fibrous layer underlying the storage layer, i.e., between the absorbent core and the backsheet. This fibrous layer is a spunlaced nowoven layer. While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention. We Claim: 1. A liquid thermoplastic composition comprising about 5% to 99% by weight of polymeric base material, and about 1% to 95% by weight of particles of superabsorbent material; characterized in that, said particles of superabsorbent material have a substantially angle-lacking shape, said particles of superabsorbent material have an average particle diameter in dry state of from 0.1 µm to 500 µm and wherein said hot melt adhesive has a viscosity at about 150°C of not more than 15000 centipoises and a 100 µm thick film of said hot melt adhesive having a basis weight of l00g/m2 has a transparency value of at least 30%. 2. The composition as claimed in claim 1, wherein said composition has a tensile strength in wet state which is at least 20% of the tensile strength of said composition in dry state. 3. The composition as claimed in any of the previous claims, wherein said particles of superabsorbent material have a spherical shape. 4. The composition as claimed in any of the previous claims, wherein said particles of superabsorbent material comprise anionic absorbent gelling material, preferably polyacrylic polymers, or cationic absorbent material or mixtures thereof. 5. The composition as claimed in any of the previous claims, wherein said particles of superabsorbent material comprise anionic absorbent gelling material in the form of partially neutralized, slightly cross-linked anionic polyacrylic polymers. 6. The composition as claimed in any of the previous claims, wherein said particles of superabsorbent material have an average particle diameter in dry state of preferably from 1 µm to 200 µm, more preferably from 10 µm to 60 µm and most preferably from 15 µm to 40 µm. 7. The composition as claimed in any of the previous claims, wherein said polymeric base material comprises thermoplastic polymer or a mixture of thermoplastic polymers, and preferably a suitable compatible plasticizer or a blend of suitable compatible plasticizers. 8. The composition as claimed in any of the previous claims, wherein said polymeric base material is a hot melt adhesive. 9. The hot melt adhesive as claimed in claim 8 wherein said hot melt adhesive comprises from 10% to 50% by weight of a block copolymer; and from 0% to 80% by weight of a tackifying resin. 10. The hot melt adhesive as claimed in claim 9, wherein said hot melt adhesive optionally comprises from 5% to 90% by weight of a suitable compatible plasticizer or a blend of suitable compatible plasticizers. 11. The composition as claimed in any of the previous claims, wherein said polymeric base material of said composition has a water absorption capacity of at least 30 when measured on a 200 µm thick film. 12. The composition as claimed in any of the previous claims, wherein said composition has a total absorption capacity towards saline solution of at least 2 g of saline solution per g of said composition. 13. The composition as claimed in any of the previous claims for use as an absorbent core or as a loading indicator in a disposable absorbent article.

Documents:

834-delnp-2005-abstract.pdf

834-delnp-2005-assignment.pdf

834-delnp-2005-claims cancelled.pdf

834-DELNP-2005-Claims.pdf

834-delnp-2005-complete specification (as,files).pdf

834-delnp-2005-complete specification (granted).pdf

834-delnp-2005-correspondence-others.pdf

834-delnp-2005-correspondence-po.pdf

834-DELNP-2005-Description (Complete).pdf

834-delnp-2005-drawings.pdf

834-delnp-2005-form-1.pdf

834-delnp-2005-form-18.pdf

834-DELNP-2005-Form-2.pdf

834-delnp-2005-form-3.pdf

834-delnp-2005-form-5.pdf

834-delnp-2005-gpa.pdf

834-delnp-2005-pct-210.pdf

834-delnp-2005-pct-220.pdf

834-delnp-2005-pct-304.pdf

834-delnp-2005-petition-137.pdf

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