MXPA99012072A - Hot melt adhesive comprising an absorbent - Google Patents

Abstract

A hot-melt adhesive containing fluid absorbing polymers and non-absorbing polymers is optionally blended with super-absorbent polymers. The resulting thermoplastic hot-melt adhesive material can be used to adhesively bond substrates such as polymeric films together, as well as, to provide additional liquid absorption capacity to non-woven fabrics or absorbent structures. This adhesively coated material is particularly useful in the construction of absorbent products such as catamenial devices, wound dressings, bandages, and diapers and the like.

Description

ABSORBENT HEAT FUSION ADHESIVE FIELD OF THE INVENTION The present invention relates to a novel adhesive, and more particularly to a hot melt adhesive which is capable of absorbing liquids.

BACKGROUND OF THE INVENTION Absorbent articles such as sanitary napkins, diapers, bandages, apposites and the like, generally contain an absorbent element. The absorbent element of conventional disposable articles is typically formed of an absorbent fabric or fibrillated wood pulp fluff and / or other natural or synthetic absorbent materials such as swamp moss or superabsorbent polymers. The absorbent member is covered with a soft, flexible, liquid-permeable top sheet that allows the body fluid to be absorbed in the fluid retaining absorbent member. Typically, a fluid impervious backing sheet is adhesively attached to the liquid pervious top sheet around a peripheral edge margin to form a flange seal and completely enclose the absorbent element to prevent fluid loss.

Heat-melt adhesives are typically used in the construction of absorbent articles to secure the liquid-permeable topsheet to the absorbent member, and also to secure the fluid-impermeable reinforcement sheet to said element. In addition, heat-melt adhesives are also used in the construction of absorbent structures for laminating multiple layers or for adhesively securing absorbent particles to a non-woven fabric or fibrous pulp.

BRIEF DESCRIPTION OF THE INVENTION An object of the present invention is to provide a hot melt adhesive which is capable of absorbing aqueous liquids. Another object of the present invention is to provide a hot melt adhesive that eliminates the risk of superabsorbent particles causing tiny holes in the barrier reinforcing sheet when the absorbent article is subjected to embossing or channeling. Another object of the present invention is to provide a hot melt adhesive that eliminates the need to handle powders during the application of superabsorbent particles to absorbent products. Another object of the present invention is to provide a hot melt adhesive that allows superabsorbent particles to be patterned onto a substrate.

Another object of the present invention is to provide a hot melt adhesive that also functions as a fluid retainer system. In accordance with the present invention, there has been provided a novel heat fusion adhesive which is capable of absorbing aqueous liquids, which comprises: from about 10% to about 50% of a block copolymer; from about 20% to about 80% of a tackifying resin; and from about 1% to about 60% of an aqueous liquid absorbent polymer. Also provided in accordance with the present invention is an absorbent article, the absorbent article comprising a liquid permeable top sheet, a liquid impervious barrier sheet, and an absorbent element between the top sheet and the barrier sheet, wherein the sheet The top sheet or the barrier sheet is adhered to the absorbent member by a heat fusion adhesive which further comprises: from about 10% to about 50% of a block copolymer; from about 20% to about 80% of a tackifying resin; and from about 1% to about 60% of an aqueous liquid absorbent polymer.

Also provided in accordance with the present invention is an absorbent article, the absorbent article comprising a liquid pervious topsheet, a liquid impermeable barrier sheet, an absorbent element between the topsheet and the barrier sheet, wherein at least a portion of the absorbent element contains a heat fusion adhesive, which further comprises: from about 10% to about 50% of a block copolymer; from about 20% to about 80% of a tackifying resin; and from about 1% to about 60% of an aqueous liquid absorbent polymer.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a top plan view of a sanitary napkin having a patterned liner. Figure 2 is a side view of the sanitary napkin of Figure 1 taken through line A-A, showing the adhesive applied between a cover layer and an absorbent element. Figure 3 is a top plan view of a sanitary napkin having a zone coating.

Figure 4 is a top plan view of a sanitary napkin having a foamed adhesive in a pattern, which forms side and end packs. Figure 5 is a side view of the sanitary napkin of Figure 4 taken through line B-B, showing the adhesive applied on an upper surface of a towel cover layer. Figure 6 is a top plan view of a sanitary napkin having a multi-line adhesive pattern. Figure 7 is a side view of the sanitary napkin of Figure 6 taken through line C-C, showing the adhesive applied between a barrier layer and an absorbent element. Figure 8 is a top plan view of a sanitary napkin having adhesive applied in a curved line pattern adjacent to each longitudinal side edge and transverse terminal region of the towel. Figure 9 is a top plan view of a sanitary napkin having adhesive applied in a curved line pattern, which forms a closed perimeter around a central region of the sanitary napkin. Figure 10 is a top plan view of a sanitary napkin having adhesive applied in an hourglass pattern in a central region of the towel. Figure 11 is a top plan view of a sanitary napkin having adhesive applied as a pair of substantially parallel lines adjacent each longitudinal side edge of the towel.

Figure 12 is a side view of the sanitary napkin of Figure 1 1 taken through lines D-D of Figure 1 1, showing the adhesive applied between a cover layer and a towel absorbent.

DETAILED DESCRIPTION OF THE PREFERRED MODALITIES The present invention relates to hot melt adhesives, and more particularly to hot melt adhesives which are useful in the construction of absorbent articles such as sanitary napkins, diapers, nursing pads, surgical aprons and bandages. Unlike traditional heat fusion adhesives that are hydrophobic in nature, the heat fusion adhesives of the present invention rapidly absorb aqueous fluids such as saline and menstrual fluid. The heat fusion adhesives of the present invention are formed from a mixture of from about 10% to about 50% of a block copolymer; from about 20% to about 80% of a tackifying resin; and from about 1% to about 60% of an aqueous liquid absorbent polymer. The hot melt adhesives of the present invention may optionally contain absorbent thermoplastic polymers, superabsorbent particles, tackifiers and plasticizers. In a preferred embodiment, the heat fusion adhesives of the present invention comprise (by weight): about 10 to 50% block copolymer; about 20 to 80% tackifying resin; about 1 to 60% aqueous polymer absorbing liquids; about 0 to 40% plasticizer; and about 0 to 2.0% antioxidant. Block copolymers suitable for use in the invention include linear or radial copolymer structures having the formula (AB) x, wherein block A is a block of polyvinylarene, block B is a block of poly (monoalkenyl) and x denotes the number of polymeric arms, and where x is an integer greater than or equal to one. Suitable block A polyvinyl aneses include, but are not limited to, polystyrene, polyalpha-methylstyrene, polyvinyl toluene, and combinations thereof. Suitable B-block poly (monoalkenyl) blocks include, but are not limited to, conjugated diene elastomers such as, for example, polybutadiene or polyisoprene, or hydrogenated elastomers such as ethylene butylene or ethylene propylene or polyisobutylene, or combinations thereof. same. Commercial examples of these types of block copolymers include Kranton ™ elastomers from Shell Chemical Company, Dexco's Vector ™ elastomers, Enichem's Solprene ™ elastomers, and elastomers Stereon ™ by Firestone Tire & Rubber Co. Suitable tackifying resins include natural and modified resins; esters of glycerol and pentaerythritol of natural and modified resins; polyterpene resins; copolymers and terpolymers of natural terpenes; modified terpene phenolic resins and the hydrogenated derivatives thereof; aliphatic petroleum resins and the hydrogenated derivatives thereof; aromatic petroleum resins and the hydrogenated derivatives thereof; and aliphatic or aromatic petroleum resins and the hydrogenated derivatives thereof, and combinations thereof. Commercial examples of these types of resins include Foral® hydrogenated resin ester, Staybelite® hydrogenated modified resin, Poly-pale® polymerized resin, Permalyn® resin ester, Pentalyn® resin ester, Adtac® hydrocarbon resin extended with oil, hydrocarbon Piccopale® aromatic, Piccotac®, Hercotac® modified aromatic aliphatic hydrocarbon, Regalrez® or Piccolyte® cycloaliphatic resins from Hercules, Eselementz® from Exxon Chemical, cycloaliphatic and aliphatic hydrocarbon resins, Wingtack® from Goodyear Tire & Rubber Co., synthetic polyterpene resins including modified aromatic versions, Arkon® partial and fully hydrogenated aromatic resins from Arakawa Chemicals, Zonatac® stretched terpene resin, Zonarez® resin ester, and Zonester® resin ester from Arizona Chemical and aliphatic hydrocarbon modified aromatic Nevtac® from Neville Chemical Company. Aqueous liquid absorbent polymers suitable include thermoplastic hydrogels such as superabsorbent materials or thermoplastic polymer compositions, which are formed of a water-soluble soft segment and one or more hard segments. The hard segment must be processable to fusion, that is, at the temperature of use, the hard segments in the polymer are below their melting temperature, and at the processing temperature, the hard segments are above their point temperature. melting and below the decomposition temperature of any of the other components of the hot melt adhesive composition. The hard segment is substantially insoluble in water, and separates the phase from the soft segment. Examples of suitable hard segments include, but are not limited to, polyurethane, polyamides, polyesters, polyureas, and combinations thereof. Examples of suitable soft segments include, but are not limited to, polyethylene oxide, polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylamide, polysaccharide, polymaleic anhydride, random copolymers of polyethylene oxide and polypropylene oxide, and combinations thereof. The soft and hard segments may be covalently linked to each other by secondary urethane, amide, ester or urea linkages, or combinations thereof. Examples of commercially available water-absorbent thermoplastic polymeric compositions include Tyndale Plains-Hunter Ltd. hydrophilic polyurethane and Aquacaulk® thermoplastic polymers from Sumitomo Seika Chemicals Co., Ltd. Suitable superabsorbent materials include any of the conventional superabsorbent particles or superabsorbent fibers which are commercially available today. The superabsorbent material is preferably a superabsorbent particle having an average particle size of less than 150 microns. An example thereof is Aquakeep® J-550 from Absorbent Technologies Inc. Suitable plasticizers for use in the present invention will generally include any conventional plasticizer that decreases hardness and modulus, increases the pressure sensitive tack, and reduces the viscosity of the plasticizer. the solution and the molten material. It is preferred that the plasticizer be water-soluble or dispersible in water, or alternatively be a wax-like substance such as polyethylene glycol, glycerin, glycerol, polypropylene glycol, butylene glycol or sorbitol. An example of a preferred plasticizer is Carbowax polyethylene glycol from Union Carbide. Suitable antioxidants for use in the present invention include any conventional antioxidant, and are preferably hindered phenols such as, for example, Ethanox 330 ™, 1, 3,5-trimethyl-2,4,6, -tris (3,5- di-tert-butyl-4-hydroxybenzyl) benzene, which is commercially available from Ethyl Corporation. The hot melt adhesives of the present invention can be formed by mixing the block copolymer, the tackifying resin and the liquid absorbent aqueous polymer in a suitable adhesive processing equipment, such as a mixer or extruder of molten material to a temperature above their respective melting points, until they mix uniformly. The heat-melt adhesive can be applied to substrates using conventional adhesive application equipment, such as a heat-melt adhesive groove coating head, a whirling spray applicator for heat melt adhesive (a commercial example of which is a Nordson Control Fiberization®), using a heat-melt adhesive microfiber applicator (commercial examples of these applicators include Nordson Control Coat®, ITW Dynaf® ber®, J &M Meltblown and May Coating's Accufiber®), using a rotary sieve applicator of heat fusion adhesive to create a patterned liner (examples of this equipment include the Nordson and Kraemer rotary screen technology). Referring to Figure 1, an absorbent article is shown, which for purposes of illustration, is a sanitary napkin 1 having opposite longitudinal sides 2, 3 and opposite transverse ends 4, 5. With reference to Figure 2, the towel 1 of figure 1 is shown in cross-section, having an upper cover layer 10 facing the body, a lower barrier layer 20 facing the garment, and the absorbent element 30 between the cover layer 10 and the barrier layer 20. The liquid-absorbent heat-melt adhesive 40 adheres the cover layer 10 to the absorbent element 30 in a pattern-coated absorbency zone 50 in a substantially rectangular pattern. The heat fusion adhesive may alternatively be located between the absorbent member 30 and the barrier layer 20 (not shown). Other patterns of adhesive and application sites are illustrated in Figures 3 to 12. For example, Figure 3 shows a top plan view of an absorbent article 301 having a cover layer 310, opposite longitudinal sides 302, 303 in an hourglass configuration, and opposed transverse ends 304, 305. The liquid-absorbing heat-melt adhesive 40 is coated by zones in the absorbency zone 350 in a substantially rectangular pattern. In the embodiment of the invention illustrated in Figures 4 and 5, a sanitary towel 401 having a cover layer 401, barrier layer 410, absorbent member 430, transfer layer 470, and aqueous melt adhesive 440 absorbent is shown. of liquids, which has been foamed by mixing the adhesive with an inert gas. The foamed adhesive is then metered and delivered through a nozzle onto a substrate, in this case the cover layer of a sanitary napkin. This technology is commercially available from Nordson Corporation using its FoamMelt® processors, and is described in more detail in Dilnik et al., U.S. Pat. No. 5,807,367, incorporated herein by reference in its entirety. As shown in Figure 4, the foamed heat melt adhesive 440 has been applied to the cover layer facing the body adjacent the longitudinal sides of the sanitary napkin 401, to form side gaskets 450, 451 and terminal gaskets. 460, 461. The heat fusion adhesive 440 can alternatively be applied between the cover layer 410 and the underlying absorbent element 430 (not shown). Referring to Figures 6 and 7, there is shown an absorbent article, which for purposes of illustration is a sanitary napkin 601 having opposite longitudinal sides 602, 603 and opposed transverse ends 604, 605. With reference to Figure 7, the sanitary pad 601 of figure 6 is shown in cross-section, having a top cover layer 610 facing the body, a lower barrier layer 620 facing the garment, and absorbent element 630 between the cover layer 610 and the barrier layer 620. The liquid-absorbent heat-melt adhesive 640 adheres the barrier layer of 620 to the absorbent element 630 in an absorbency zone 650 coated with multiple lines in a substantially rectangular pattern. Figure 8 shows a top plan view of an absorbent article 801 having a cover layer 810, opposite longitudinal sides 802, 803 in an hourglass configuration, and opposite transverse ends 804, 805. The heat fusion adhesive 840 Liquid absorbent is applied in a curved line pattern to form opposite lateral absorbency zones 841, 842 and opposite transverse terminal absorbency zones 843, 844. Figures 9 and 10 show a top plan view of absorbent articles 901, 920, respectively, having an adhesive pattern in a substantially hourglass shape. Figure 9 has a cover layer 910, opposite longitudinal sides 902, 903 in an hourglass configuration, and opposed transverse ends 904, 905. Referring again to Figures 9 and 10, the heat fusion adhesive 940 , 960 liquid absorbent is applied to the article to form an hourglass 950, 965 absorbency zone (respectively).

Referring to Figures 11 and 12, an absorbent article is shown, which for purposes of illustration is a sanitary napkin 1101 having opposite longitudinal sides 1 102, 1 103 and opposite transverse ends 1 104, 1 105. With respect to Figure 12, the sanitary napkin 1 101 of Figure 1 1 is shown in cross section, having an upper cover layer 1 1 10 facing the body, a lower barrier layer 1120 facing the garment, and an absorbent element 1130 between the cover layer 1 1 10 and the barrier layer 1 120. The heat-absorbing adhesive 1 140 liquid absorbent is adhered to the cover layer 1 1 10 and the absorbent element 1130 in an absorbency zone 1 150 lined with parallel lines.

EXAMPLE 1 The aqueous liquid-absorbent melt adhesive of the present invention was evaluated for its viscosity characteristics of molten material, adhesive strength (peel strength measured on a non-woven polypropylene fabric) and ability to absorb aqueous saline solution (absorbent capacity) with respect to a conventional heat fusion adhesive. The conventional heat fusion adhesive was commercially available from the Fuller Company under the tradename HL-1491 ™. This is a standard heat fusion adhesive which is often used in the construction of absorbent articles such as sanitary napkins, panty liners, diapers, and the like. It is thought that the conventional adhesive formulation is in the following approximate proportions: 15 to 20% of a styrene-isoprene-styrene block copolymer with a styrene content of 30%; 60 to 70% of an aliphatic resin of modified aliphatic or aromatic tack; 15 to 20% mineral oil; < of 2% antioxidant; and < of 2% additional adjuvants (wax and polyethylene). Two examples of the heat fusion adhesive of the present invention had the following formulas: Sample A 5.7% block copolymer (Vector DPX-552 ™) 33.7% tackifying resin (Foral 85 ™) 10.0% aqueous polymer absorbing liquids (Aquacaulk TQU-5 ™) 40.0% superabsorbent particles (Aquakeep J55-P ™) 10.5% plasticizer (Peg 600 ™) and 0.5% antioxidant (Ethanox 330 ™).

Sample B 15.0% block copolymer (Vector DPX-552 ™) 25.0% tackifying resin (Foral 85 ™) 0.0% aqueous absorbent polymer from liquids (Aquacaulk TQU-5 ™) 45.0% superabsorbent particles (Aquakeep J55- P ™) 15.0% plasticizer (Peg 600 ™) and 0.5% antioxidant (Ethanox 330 ™).

The results of the evaluation are given in the following table 1: TABLE 1 Sample Sample Commercial sample A B Viscosity at 177 ° C, 101, 000 1 100 10,000 (centipoise) Absorbent capacity (g / g) null 9.4 10.3 Resistance to detachment 19.63 5.35 21.06 (kg / m width) The commercially available heat fusion adhesive did not exhibit substantially any absorbency, while the heat fusion adhesive of the present invention absorbed approximately 10 g of liquid per gram of adhesive. In addition, the adhesive composition of the present invention did not experience a decrease in its adhesive strength.

Claims (29)

NOVELTY OF THE INVENTION CLAIMS

1. - A hot melt adhesive that is capable of absorbing aqueous liquids, characterized in that it comprises: from about 10% to about 50% of a block copolymer; from about 20% to about 80% of a tackifying resin; and from about 1% to about 60% of an aqueous liquid absorbent polymer.

2. The heat fusion adhesive according to claim 1, further characterized in that the block copolymer is a linear or radial copolymer structure having the formula (AB) x, wherein the block A is a block of polyvinyl anerylene , block B is a block of poly (monoalkenyl) and x denotes the number of polymeric arms, and where x is an integer greater than or equal to one.

3. The heat-melt adhesive according to claim 2, further characterized in that the polyvinylaneses of block A are selected from the group consisting of polystyrene, polyalpha-methylstyrene, polyvinyl toluene, and combinations thereof, and wherein the blocks of poly (monoalkenyl) of block B are selected from the group consisting of conjugated diene elastomers, hydrogenated elastomers, and combinations thereof.

4. - The heat fusion adhesive according to claim 3, further characterized in that the conjugated diene elastomers are selected from the group consisting of polybutadiene and polyisoprene, and wherein the hydrogenated elastomers are selected from the group consisting of ethylene butylene, ethylene propylene, polyisobutylene, and combinations thereof.

5. The heat-melt adhesive according to claim 1, further characterized in that the heat-melt adhesive further contains absorbent thermoplastic polymers, superabsorbent particles, tackifiers and plasticizers.

6. The hot melt adhesive according to claim 1, further characterized in that the tackifying resins are selected from the group consisting of natural resins, modified resins, glycerol esters of natural resins, glycerol esters of modified resins, esters of pentaerythritol of natural resins, pentaerythritol esters of modified resins; poiiterpene resins, copolymers of natural terpenes, terpolymers of natural terpenes, modified phenolic terpene resins and hydrogenated derivatives thereof, aliphatic petroleum resins and hydrogenated derivatives thereof, aromatic petroleum resins and hydrogenated derivatives thereof, resins of aliphatic petroleum, hydrogenated derivatives of aliphatic petroleum resins, aromatic petroleum resins, hydrogenated derivatives of aromatic petroleum resins, and combinations thereof.

7. - The heat-melt adhesive according to claim 1, further characterized in that the liquid-absorbent aqueous polymers are selected from the group consisting of thermoplastic hydrogels and thermoplastic polymer compositions which are formed of a water-soluble soft segment and one or more hard segments .

8. The hot melt adhesive according to claim 7, further characterized in that the hard segments are selected from the group consisting of polyurethane, polyamides, polyesters, polyureas, polypropylene oxide, and combinations thereof.

9. The hot melt adhesive according to claim 7, further characterized in that the soft segments are selected from the group consisting of polyethylene oxide, polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylamide, polysaccharide, polymaleic anhydride and random oxide copolymers of polyethylene and polypropylene oxide.

10. An absorbent article comprising a liquid permeable upper sheet, a liquid impermeable barrier sheet and an absorbent element between the upper sheet and the barrier sheet, characterized in that the upper sheet or the barrier sheet is adhered to the element absorbent by a heat fusion adhesive, which further comprises: from about 10% to about 50% of a block copolymer; from about 20% to about 80% of a tackifying resin; and from about 1% to about 60% of an aqueous liquid absorbent polymer.

11. - The absorbent article according to claim 10, further characterized in that the article is selected from the group consisting of sanitary napkins, panty liners, incontinence devices in the adult and diapers.

12. The hot melt adhesive according to claim 10, further characterized in that the block copolymer is a linear or radial copolymer structure having the formula (AB) x, wherein the block A is a block of polyvinylarene , block B is a block of poly (monoalkenyl) and x denotes the number of polymeric arms, and where x is an integer greater than or equal to one.

13. The hot melt adhesive according to claim 12, further characterized in that the block polyvinylanes A are selected from the group consisting of polystyrene, polyalpha methylstyrene, polyvinyl toluene, and combinations thereof, and wherein the blocks of poly (monoalkenyl) of block B are selected from the group consisting of conjugated diene elastomers, hydrogenated eiastomers, and combinations thereof.

14. The heat fusion adhesive according to claim 13, further characterized in that the conjugated diene elastomers are selected from the group consisting of polybutadiene and polyisoprene, and wherein the hydrogenated elastomers are selected from the group consisting of ethylene butylene , ethylene propylene, polyisobutylene, and combinations thereof.

15. - The heat-melt adhesive according to claim 10, further characterized in that the heat-melt adhesive further contains absorbent thermoplastic polymers, superabsorbent particles, tackifiers and plasticizers.

16. The hot melt adhesive according to claim 10, further characterized in that the tackifying resins are selected from the group consisting of natural resins, modified resins, glycerol esters of natural resins, glycerol esters of modified resins, esters of pentaerythritol of natural resins, pentaerythritol esters of modified resins; polyterpene resins, copolymers of natural terpenes, terpolymers of natural terpenes, modified phenolic terpene resins and hydrogenated derivatives thereof, aliphatic petroleum resins and hydrogenated derivatives thereof, aromatic petroleum resins and hydrogenated derivatives thereof, resins of aliphatic petroleum, hydrogenated derivatives of aliphatic petroleum resins, aromatic petroleum resins, hydrogenated derivatives of aromatic petroleum resins, and combinations thereof.

17. The heat-melt adhesive according to claim 10, further characterized in that the liquid-absorbent aqueous polymers are selected from the group consisting of thermoplastic hydrogels and thermoplastic polymer compositions which are formed of a water-soluble soft segment and one or more hard segments.

18. - The heat-melt adhesive according to claim 17, further characterized in that the hard segments are selected from the group consisting of polyurethane, polyamides, polyesters, polyureas, polypropylene oxide, and combinations thereof.

19. The heat fusion adhesive according to claim 17, further characterized in that the soft segments are selected from the group consisting of polyethylene oxide, polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylamide, polysaccharide, polymaleic anhydride and random copolymers of oxide of polyethylene and polypropylene oxide.

20. An absorbent article comprising a liquid-permeable upper sheet, a liquid-impermeable barrier sheet and an absorbent element between the upper sheet and the barrier sheet, characterized in that the upper sheet or the barrier sheet is adhered to the element absorbent by a heat fusion adhesive, which further comprises: from about 10% to about 50% of a block copolymer; from about 20% to about 80% of a tackifying resin; and from about 1% to about 60% of an aqueous liquid absorbent polymer.

21. The absorbent article according to claim 20, further characterized in that the article is selected from the group consisting of sanitary napkins, linings of panties, devices for incontinence in the adult and diapers.

22. - The hot melt adhesive according to claim 20, further characterized in that the block copolymer is a linear or radial copolymer structure having the formula (AB) ?, wherein the block A is a block of polyvinylarene, the block B is a block of poly (monoalkenyl) and x denotes the number of polymeric arms, and where x is an integer greater than or equal to one.

23. The heat-melt adhesive according to claim 22, further characterized in that the polyvinylaneses of block A are selected from the group consisting of polystyrene, polyalpha-methylstyrene, polyvinyl toluene, and combinations thereof, and wherein the blocks of poly (monoalkenyl) of block B are selected from the group consisting of conjugated diene elastomers, hydrogenated elastomers, and combinations thereof.

24. The heat fusion adhesive according to claim 23, further characterized in that the conjugated diene elastomers are selected from the group consisting of polybutadiene and polyisoprene, and wherein the hydrogenated elastomers are selected from the group consisting of ethylene butylene , ethylene propylene, polyisobutylene, and combinations thereof.

25. The hot melt adhesive according to claim 20, further characterized in that the hot melt adhesive further contains absorbent thermoplastic polymers, superabsorbent particles, tackifiers and plasticizers.

26. - The heat-melt adhesive according to claim 20, further characterized in that the tackifying resins are selected from the group consisting of natural resins, modified resins, glycerol esters of natural resins, glycerol esters of modified resins, pentaerythritol esters of natural resins, pentaerythritol esters of modified resins; polyterpene resins, copolymers of natural terpenes, terpolymers of natural terpenes, modified phenolic terpene resins and hydrogenated derivatives thereof, aliphatic petroleum resins and hydrogenated derivatives thereof, aromatic petroleum resins and hydrogenated derivatives thereof, resins of aliphatic petroleum, hydrogenated derivatives of aliphatic petroleum resins, aromatic petroleum resins, hydrogenated derivatives of aromatic petroleum resins, and combinations thereof.

27. The heat-melt adhesive according to claim 20, further characterized in that the liquid-absorbent aqueous polymers are selected from the group consisting of thermoplastic hydrogels and thermoplastic polymer compositions which are formed of a water-soluble soft segment and one or more hard segments.

28. The hot melt adhesive according to claim 27, further characterized in that the hard segments are selected from the group consisting of polyurethane, polyamides, polyesters, polyureas, polypropylene oxide, and combinations thereof.

29. - The heat fusion adhesive according to claim 27, further characterized in that the soft segments are selected from the group consisting of polyethylene oxide, polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylamide, polysaccharide, polymaleic anhydride and random copolymers of polyethylene oxide and polypropylene oxide.