Method of manufacturing and bonding shoe rubber outsoles

Abstract

The present invention relates to a method of manufacturing shoe rubber outsoles using a special heat and pressure stable water-based polyurethane dispersion adhesive without the need for UV irradiation or plasma pretreatment, as well as a method of manufacturing shoes using shoe outsoles manufactured as described herein and PUD-based adhesive compositions for use in said method.

Description

TECHNICAL FIELD

[0001] The present invention relates to a method of manufacturing a shoe rubber outsole using a special heat and pressure stable water-based polyurethane dispersion adhesive without the need for UV irradiation or plasma pretreatment, and a method of manufacturing a shoe using a shoe outsole manufactured as described herein and a polyurethane dispersion-based adhesive composition for the method. BACKGROUND

[0002] Generally, a rubber outsole is prepared by vulcanizing an unvulcanized rubber cut into a planar or structured shape. Examples of conventional technology related to such a rubber outsole preparation method are disclosed in Korean Patent Registration No. 10-0191275 and Korean Patent Application Publication No. 2000-0063527, and International Patent Publication No. WO 2011 / 020757 A2.

[0003] Korean Patent Registration No. 10-0191275 discloses a method of integrally forming a rubber outsole and a polyurethane midsole of a shoe, comprising the steps of: forming a rubber outsole so that a belt-shaped protrusion having a predetermined width is provided on its entire periphery, and a net-like arrangement of protrusions is formed on its surface; heat-treating the rubber outsole so that its surface temperature is about 40 to 50°C; and spraying an undiluted polyurethane solution onto the heat-treated rubber outsole to integrally form a midsole on the rubber outsole.

[0004] Korean Patent Application Publication No. 2000-0063527 discloses a shoe outsole and a method of manufacturing the same, in which a shoe outsole and a midsole are simultaneously formed and adhered by a single method.

[0005] International Patent Publication No. WO 2011 / 020757 A2 discloses a method of manufacturing a shoe by using a multifunctional primer. In the method, an unvulcanized rubber outsole is coated with a multifunctional primer comprising a polyurethane dispersion (PUD), a butadiene rubber solution, and a natural rubber solution before vulcanization. The shoe outsole is then heat-activated, coated with an adhesive, and adhered to other shoe components.

[0006] International Patent Publication No. WO 2017103063 A1 discloses a method of manufacturing a shoe rubber outsole, comprising the steps of: (1) treating an unhardened rubber material by UV irradiation or plasma; (2) applying an adhesive composition to the treated rubber material of step (1) and drying the rubber material, wherein the adhesive composition comprises a heat and pressure stable water-based polyurethane dispersion; (3) curing the rubber material resulting from step (2).

[0007] Although the methods described above are superior to conventional methods because they provide a way to avoid laborious additional washing steps, there is still a need in the prior art to simplify the manufacturing process of rubber outsoles and / or shoes.

[0008] Therefore, the object of the present invention is to provide a further simplified method for manufacturing shoes. Summary of the Invention

[0009] To achieve the above objectives, a first aspect of the present invention provides a method for manufacturing a rubber outsole for shoes, comprising the following steps:

[0010] (1) Provide uncured rubber material;

[0011] (2) Applying the adhesive composition to the uncured rubber material of step (1) and drying the uncured rubber material, wherein the adhesive composition comprises a heat- and pressure-stable water-based polyurethane dispersion; and

[0012] (3) Curing the rubber material obtained in step (2),

[0013] The adhesive composition comprises, relative to the total weight of the composition:

[0014] a) 85% to 99.9% by weight of an aqueous polyurethane dispersion, preferably a polyurethane based on a polyester polyol;

[0015] b) At least one crosslinking agent, preferably polycarbodiimide, at 0.1% to 1% by weight;

[0016] c) 0.1% to 10% by weight of at least one modified polyolefin-based adhesive promoter, which preferably comprises a modified polyolefin, (meth)acrylate and an emulsifier;

[0017] d) At least one filler, preferably fumed silica, comprising 0% to 5% by weight;

[0018] e) at least one fluorescent agent, ranging from 0.5% to 0.1% by weight; and

[0019] f) 0% to 1% by weight of at least one HEUR thickener.

[0020] In another aspect, the present invention relates to a method of manufacturing shoes, comprising:

[0021] (1) Thermal activation of the shoe rubber outsole obtained according to the method for manufacturing shoe rubber outsoles described herein; and

[0022] (2) Adhere the activated rubber outsole to one or more other shoe components, preferably the insole interlayer.

[0023] In another aspect, the invention also relates to an adhesive composition for uncured rubber materials, comprising, by weight of the composition:

[0024] a) 85% to 99.9% by weight of an aqueous polyurethane dispersion, preferably a polyurethane based on a polyester polyol;

[0025] b) At least one crosslinking agent, preferably polycarbodiimide, at 0.1% to 1% by weight;

[0026] c) 0.1% to 10% by weight of at least one modified polyolefin-based adhesive promoter, which preferably comprises a modified polyolefin, (meth)acrylate and an emulsifier;

[0027] d) At least one filler, preferably fumed silica, comprising 0% to 5% by weight;

[0028] e) at least one fluorescent agent, ranging from 0.5% to 0.1% by weight; and

[0029] f) 0% to 1% by weight of at least one HEUR thickener.

[0030] The present invention also covers the use of the adhesive composition for treating uncured rubber materials, preferably for treating rubber outsoles of shoes.

[0031] It has been surprisingly found that by using the method described herein, several washing steps, as well as separate priming and cementing steps, required in conventional methods known, for example, from KR10-0191275 and KR 2000-0063527, can be omitted. Furthermore, the special treatments by UV irradiation or plasma disclosed in WO 2017103063 A1 can be eliminated. The application of special heat- and pressure-stabilized PUDs eliminates the need for these additional steps, thus significantly simplifying and accelerating the manufacturing process. More specifically, existing methods involve a first step of hot-pressing an uncured rubber outsole to cure the rubber material, followed by steps of degreasing, drying, priming, another drying step, heat-activating the rubber outsole material, applying adhesive, drying, and adhering other shoe components. The improved method described in WO 2011 / 020757 A2 still requires the use of a multifunctional priming composition applied to the uncured rubber material of the outsole without a pre-degreasing step before curing. After curing, the material is thermally activated, and then an adhesive is applied to facilitate the adhesion of other shoe components. The further improved method described in WO 2017103063 A1 still requires UV radiation or plasma pretreatment of the rubber material. In contrast to these methods, this method includes the step of providing uncured material instead of a base coat treatment step, followed by direct application of the adhesive composition without UV irradiation or plasma treatment. After curing, the rubber outsole material is thermally activated at a temperature of at least 55°C, and then other shoe components are adhered. Detailed Implementation

[0032] In this article, "heat and pressure stable" for PUD adhesives refers to PUDs that can withstand the heat and pressure typically used for rubber curing (i.e., vulcanization). This typically refers to temperatures of approximately 150-200°C, usually around 160°C, and pressures of 50-200 bar (kgf / cm²). 2 The pressure is typically around 150 bar, lasting for about 5-10 minutes. This means that the PUD will not suffer substantial polymer degradation under these conditions.

[0033] It has been found that the adhesive compositions according to the invention can achieve excellent bond strength when directly cured / crosslinked on the rubber surface during rubber vulcanization without pretreatment by UV radiation or plasma. This has the advantage of not requiring an additional primer used to ensure compatibility and adhesion between the rubber material and the adhesive.

[0034] The rubber material can be any known rubber material used in shoe production. Therefore, this includes both natural and synthetic rubber materials, such as butadiene-based rubbers, particularly butadiene rubber, acrylonitrile-butadiene rubber, styrene-butadiene-styrene rubber, etc. The rubber material provided in step (1) of the method described herein can have been pre-formed into a planar or structured shape for the shoe outsole, for example by cutting or any other forming technique. The final form of the outsole is typically obtained during the curing process, usually by hot pressing.

[0035] In the next step, the uncured and untreated rubber material is brought into contact with an adhesive composition containing PUD, typically by spraying / brushing / painting the composition onto the surface of the rubber material. Alternatively, other well-known coating and application techniques may be used. PUD is a water-based polyurethane polymer dispersion, preferably containing 30% by weight or more, typically 40% to 60% by weight, of solids (e.g., determined by measuring drying loss at 150°C for 30 minutes to evaporate water / solvent), wherein the solids consist primarily of polyurethane polymer particles with a diameter of 30-1000 nm, preferably 100-500 nm, more preferably 150-300 nm (determined by dynamic light scattering (DLS) according to ISO 22412).

[0036] The liquid phase of the dispersion contains or is composed of water, and in some embodiments, although it is preferably composed substantially of water, i.e., up to about 95% by volume, it may also include small amounts of organic solvents or other liquid components. In the PUD, the liquid phase accounts for 40% to 70% by weight, typically 40% to 60% by weight.

[0037] The polyurethane polymer particles can be made from any suitable polyurethane, typically thermoplastic polyurethane, preferably from polyester or polyester polyol and a polyisocyanate in a molar excess relative to the isocyanate and hydroxyl groups. The polyol is preferably a linear polyol. Thus, in various embodiments, the polyurethane is an NCO-terminated polyurethane, preferably obtained from a reaction mixture comprising a polyester polyol, more preferably from a reaction mixture comprising adipic acid and 1,4-butanediol, and a polyisocyanate in a molar excess relative to the isocyanate and hydroxyl groups, preferably an aliphatic diisocyanate, more preferably hexamethylene diisocyanate (HDI) or isophorone diisocyanate (IPDI).

[0038] In various embodiments, in addition to the PUD comprising polyurethane polymer particles and water, the adhesive composition may also contain one or more other components, such as known additives, including fillers, stabilizers, preservatives, defoamers, emulsifiers, rheology modifiers, colorants, etc.

[0039] The adhesive composition of the present invention preferably contains at least one crosslinking agent, which is preferably selected from polycarbodiimide and polyaziridine, more preferably polycarbodiimide. Exemplary crosslinking agents that can be used according to the invention include, but are not limited to, N,N'-dicyclohexylcarbodiimide (DCC) and N,N'-diisopropylcarbodiimide (DIC). Crosslinking agents are advantageous because they make polyurethane thermally and pressure-stable and less prone to degradation, as described above. Commercially available PUD-based adhesives without such crosslinking agents generally lack the thermal and pressure stability required to withstand rubber vulcanization conditions.

[0040] Modified polyolefin-based adhesion promoters improve the compatibility of rubber and PUD in adhesives and modify the rubber surface to generate initial cohesive force growth.

[0041] As a major component in adhesion promoters, modified polyolefins typically include modified polyolefins obtained through modifications such as unsaturated carboxylic acids or anhydrides, acryloyl groups, chlorination, or combinations thereof. As modified polyolefins with polyoxyethylene chains, polyoxyethylene chains, polyoxypropylene chains, or block chains of polyoxyethylene and polyoxypropylene can be used.

[0042] The adhesion promoter optionally comprises one or more (meth)acrylates to improve compatibility with the rubber and the bonded adhesive layer, and thereby increase the adhesive properties of the adhesive composition. Examples of (meth)acrylates include alkyl esters of (meth)acrylate, such as methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate or isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate or tert-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, cyclohexyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, etc., any of which may be used alone or in combination of two or more. Throughout this specification, the term "(meth)acrylate" means "acrylic acid or methacrylic acid," and the term "(meth)acrylate" means "acrylate or methacrylate."

[0043] The modified polyolefin can be added to the adhesive composition as an aqueous dispersion, which is obtained by dispersing the modified polyolefin in an aqueous medium and optionally adding an emulsifier.

[0044] Examples of emulsifiers include nonionic emulsifiers such as polyoxyethylene monooleate, polyoxyethylene monostearate, polyoxyethylene monolauryl ether, polyoxyethylene tridecyl ether, polyoxyethylene phenyl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene octylphenyl ether, polyoxyethylene monolaurate, polyoxyethylene monostearate, polyoxyethylene monooleate, sorbitol monolaurate, sorbitol monostearate, sorbitol trioleate, and polyoxyethylene sorbitol monolaurate; and anionic emulsifiers such as sodium or ammonium salts of alkyl sulfonic acids, alkylbenzene sulfonic acids, and alkyl phosphoric acids; and anionic emulsifiers containing polyoxyethylene groups, such as polyoxyethylene groups or polyoxypropylene groups, having anionic groups and polyoxyethylene groups in the molecule, or reactive anionic emulsifiers having anionic groups and polymerizable unsaturated groups in the molecule, any of which may be used alone or in combination of two or more.

[0045] In various embodiments, the adhesive composition comprises, relative to the total weight of the composition:

[0046] a) 85% to 99.9% by weight, preferably 90% to 99% by weight, of a water-based polyurethane dispersion;

[0047] b) At least one crosslinking agent, from 0.1% to 1% by weight, preferably from 0.1% to 0.5% by weight;

[0048] c) 0.1% to 20% by weight, preferably 0.05% to 10% by weight, of at least one modified polyolefin-based adhesion promoter;

[0049] d) At least one filler, from 0% to 5% by weight, preferably from 0.2% to 3% by weight;

[0050] e) at least one fluorescent agent, from 0% to 0.1% by weight, preferably from 0.01% to 0.05% by weight; and

[0051] f) At least one HEUR thickener, from 0% to 1% by weight, preferably from 0.3% to 0.8% by weight.

[0052] In a preferred embodiment, the modified polyolefin-based adhesion promoter comprises a modified polyolefin, (meth)acrylate, and an emulsifier. The filler used in the adhesive composition is selected from all known fillers suitable for PUD-based adhesives and the disclosed rubber applications. A preferred filler is fumed silica.

[0053] Another group of preferred additives for use in adhesive compositions are optical brighteners. Optical brighteners commonly used in adhesives can be used here. They are added to the polymer solution in aqueous solution or in an organic solvent. Examples of optical brighteners are derivatives of diaminostilbene disulfonic acid or alkali metal salts thereof. For example, suitable are salts of 4,4'-bis(2-anilino-4-morpholino-1,3,5-triazinyl-6-amino)stilbene-2,2'-disulfonic acid, or compounds with similar structures, carrying a diethanolamine, methylamino, aniline, or 2-methoxyethylamino group instead of a morpholino group. Furthermore, substituted diphenylstyrene-type brighteners can be present in the adhesive composition; examples are alkali metal salts of 4,4'-bis(2-sulfostyrene)biphenyl, 4,4'-bis(4-chloro-3-sulfostyrene)biphenyl, or 4-(4-chlorostyrene)-4'-(2-sulfostyrene)biphenyl. Mixtures of the above brighteners can also be used.

[0054] HEUR-type thickeners (hydrophobically modified ethylene oxide-urethane block copolymers) are also known in the art, and all thickeners of these types suitable for the disclosed applications can be used.

[0055] The adhesive composition is preferably a liquid, and, as measured by a Brookfield viscometer (shaft number 63, 12 rpm), has a viscosity of less than 5,000 mPa·s at 25°C, preferably from 10 mPa·s to 2,000 mPa·s, and more preferably from 50 mPa·s to 1,000 mPa·s. This allows the composition to be easily applied to uncured rubber materials using existing instruments without unnecessary dripping, etc.

[0056] The curing step of the rubber material treated with the adhesive composition is preferably carried out by hot pressing. This hot pressing results in the vulcanization of the rubber and is typically performed at temperatures above 120°C, such as 150-200°C, preferably about 160°C, and under elevated pressures, such as 50 bar or higher, typically 50-200 bar, preferably about 150 bar. The time for this hot pressing is sufficient to allow the rubber material to fully cure, typically 2 minutes or more, such as 3-30 minutes, typically 5-10 minutes. For hot pressing, known and existing instruments can be used. In practice, the hot pressing step is performed under the same conditions as currently known in the art and using the same instruments. As mentioned above, the curing step may also include giving the rubber material the final shape of the outsole. Typically, the rubber material is provided in the form of a preform, which may, for example, be roughly cut into the shape of an outsole. In these embodiments, the curing process, particularly by hot pressing, imparts the final shape of the outsole. Therefore, the hot pressing (vulcanization) can be performed in a mold.

[0057] Apart from the steps described above, the manufacture of shoe rubber outsoles preferably does not include additional washing steps or steps of applying a base coat or adhesive. However, a drying step may be performed after the adhesive is applied.

[0058] Once the outsole has been manufactured, the rubber outsole can be used to manufacture the entire shoe. In this method, the outsole is typically adhered to other shoe components, particularly the midsole. This method is usually carried out by heat-activating the rubber outsole and then adhering other shoe components, particularly the midsole, to the outsole. Other shoe components that can be adhered to the outsole or midsole in this method include, but are not limited to, an insole, an upper, etc.

[0059] The process of heat-activating the rubber outsole material is generally known in the art and preferably includes heating the material to a temperature greater than 50°C or 55°C or higher. A temperature of 55°C to 65°C is preferred. This step preferably takes 30 to 200 seconds, more preferably about 100 seconds. Thereafter, the activated rubber outsole is typically adhered to another shoe component, preferably a midsole, and optionally an upper part of the shoe, using a hydraulic (walled) sole attaching machine.

[0060] As already described in conjunction with the method of manufacturing the outsole, the method of manufacturing the shoe preferably does not include any additional steps of degreasing or cleaning the outsole before heat activation and adhesion, nor does it include a step of applying a rubber outsole coating or another adhesive before the activation and adhesion steps. However, other shoe components, particularly the midsole layer, may be conventionally treated before being adhered to the outsole.

[0061] As described above, compared with conventional shoe manufacturing methods, the shoe manufacturing method according to the present invention has the advantage of eliminating the need for cleaning and coating steps on the rubber outsole, thereby improving productivity. Furthermore, the shoe manufacturing method according to the present invention has the advantage of reducing production costs by decreasing the number of workers and facilities due to the elimination of the washing and coating processes, and of manufacturing shoes in an environmentally friendly manner by eliminating the washing process.

[0062] This invention also covers the use of special adhesive compositions in the methods of this invention and their application in treating uncured rubber materials, preferably shoe rubber outsoles. It should be understood that all embodiments disclosed above relating to the methods of this invention, particularly those relating to the composition of the adhesive, are equally applicable to the adhesive compositions themselves and their uses.

[0063] While preferred embodiments of the invention have been disclosed for illustrative purposes, those skilled in the art will understand that various modifications, additions, and substitutions are possible without departing from the scope and spirit of the invention as disclosed in the appended claims.

[0064] The following examples are used to further illustrate the present invention, but are not limited thereto.

[0065] Example

[0066] Example 1: Adhesive Composition

[0067]

[0068]

[0069] manufacture:

[0070] 1. Charge Pot No. 1 and begin mixing for 30 minutes. 2. Charge Pot No. 2 and No. 3 and mix for 1 hour at room temperature. 3. Slowly charge Pot No. 4 and mix for 1 hour. 4. Slowly charge Pot No. 5 and mix for 1 hour. 5. Charge Pot No. 6 by slow addition over 1 hour and mix for 3 hours.

[0071] Example 2: Shoemaking

[0072] The adhesive composition according to Example 1 was uniformly applied to the unvulcanized rubber outsole using a sprayer, followed by a rubber vulcanization process at 160°C and 150 bar for 420 seconds. The vulcanized rubber outsole was then heat-activated in a heating chamber at 55°C for approximately 100 seconds. Subsequently, the heat-activated rubber outsole was manually adhered to the midsole and upper, and then further adhered using a hydraulic wall-mounted sole adhesive machine to manufacture the shoe.

[0073] After 1 day and / or 18 days, the bond strength between the rubber outsole and the sole interlayer is measured by peel strength using a peel tester (5580, Instron).

[0074] The shoes manufactured according to the present invention have adhesive strengths of 7.5 kgf / cm² after 1 day and 18 days, respectively. 2 and 8.1 kgf / cm 2 Furthermore, the rubber material was damaged. For shoes manufactured using the same method but with Dispercoll U 2793XP (a PUD-based adhesive purchased from Bayer Material Science), bond strengths after 1 day and 18 days were also observed to be only 4.0 kgf / cm². 2 and 4.3 kgf / cm 2 Furthermore, the adhesive separates from the rubber material.

[0075] For comparative purposes, the average bond strength of shoes manufactured according to conventional manufacturing methods using UV radiation pretreatment as described in Example 1 of WO 2017103063 A1, and the average bond strength of shoes manufactured according to the method steps of the present invention but using an adhesive composition without an adhesion promoter, were both measured to be 5.0 kgf / cm². 2 and 3.5 kgf / cm 2 (Point failure exists), which is significantly lower than the bond strength obtained by the method according to the invention.

Claims

1. A method for manufacturing a shoe rubber outsole, comprising the following steps: (1) Provide uncured rubber material; (2) Applying the adhesive composition to the uncured rubber material from step (1) and drying the rubber material, wherein the adhesive composition comprises a heat- and pressure-stable water-based polyurethane dispersion; and (3) Curing the rubber material obtained in step (2), The adhesive composition comprises, relative to the total weight of the composition: a) 85% to 99.9% by weight of water-based polyurethane dispersions; b) At least one crosslinking agent, ranging from 0.1% to 1% by weight; c) 0.1% to 10% by weight of at least one adhesive accelerator based on modified polyolefin; d) At least one filler, ranging from 0% to 5% by weight; e) at least one fluorescent whitening agent, from 0% by weight to 0.1% by weight; and f) 0% to 1% by weight of at least one HEUR thickener.

2. The method according to claim 1, wherein the polyurethane is a polyester polyol-based polyurethane.

3. The method according to claim 1, wherein the crosslinking agent is polycarbodiimide.

4. The method according to claim 1, wherein the filler is fumed silica.

5. The method according to claim 1, wherein (i) The uncured rubber material in step (1) is a pre-formed rubber outsole for shoes; and / or (ii) In step (3), the rubber material obtained in step (2) is cured and formed into a shoe rubber outsole; and / or (iii) In step (3), the rubber material is cured by hot pressing.

6. The method according to any one of claims 1 to 5, wherein the method does not include the additional step of treating the uncured rubber material by UV radiation or plasma.

7. The method according to any one of claims 1 to 5, wherein the polyurethane is an NCO-terminated polyurethane.

8. The method of claim 7, wherein the polyurethane is obtained from a reaction mixture comprising a polyester polyol.

9. The method of claim 7, wherein the polyurethane is obtained from a reaction mixture comprising adipic acid and 1,4-butanediol, and a polyisocyanate in molar excess relative to the isocyanate and hydroxyl groups.

10. The method according to claim 9, wherein the polyisocyanate is an aliphatic diisocyanate.

11. The method of claim 9, wherein the polyisocyanate is HDI or IPDI.

12. The method according to any one of claims 1 to 5, wherein the crosslinking agent is selected from polycarbodiimide and polyaziridine.

13. The method according to any one of claims 1 to 5, wherein the modified polyolefin-based adhesion promoter comprises a modified polyolefin obtained by modification of the polyolefin by unsaturated carboxylic acid or anhydride, acryloyl group modification, chlorination modification, or a combination thereof.

14. The method according to any one of claims 1 to 5, wherein the adhesive composition is a liquid and has a viscosity of less than 5,000 mPa·s at 25°C, as determined by a Brookfield viscometer with shaft number 63 and 12 rpm.

15. The method of claim 14, wherein the viscosity of the adhesive composition at 25°C is from 10 mPa·s to 2,000 mPa·s, as determined by a Brookfield viscometer with shaft number 63 and 12 rpm.

16. The method of claim 14, wherein the viscosity of the adhesive composition at 25°C is from 50 mPa·s to 1,000 mPa·s, as determined by a Brookfield viscometer with shaft number 63 and 12 rpm.

17. A method for manufacturing shoes, comprising: (1) Thermally activating the rubber outsole of the shoe obtained by the method according to any one of claims 1 to 16; and (2) Adhere the activated rubber outsole to one or more other shoe components.

18. The method of claim 17, wherein the other shoe component is a sole interlayer.

19. The method according to claim 17 or 18, wherein the method does not include the additional steps of degreasing or cleaning or applying an adhesive to the rubber outsole of the shoe prior to step (2).

20. An adhesive composition for use with uncured rubber materials, comprising, relative to the total weight of the composition: a) 85% to 99.9% by weight of water-based polyurethane dispersions; b) At least one crosslinking agent, ranging from 0.1% to 1% by weight; c) 0.1% to 10% by weight of at least one adhesive accelerator based on modified polyolefin; d) At least one filler, ranging from 0% to 5% by weight; e) at least one fluorescent whitening agent, from 0% by weight to 0.1% by weight; and f) 0% to 1% by weight of at least one HEUR thickener.

21. The adhesive composition of claim 20, wherein the polyurethane is a polyester polyol-based polyurethane.

22. The adhesive composition of claim 20, wherein the crosslinking agent is polycarbodiimide.

23. The adhesive composition of claim 20, wherein the adhesive promoter comprises a modified polyolefin, (meth)acrylate, and an emulsifier.

24. The adhesive composition of claim 20, wherein the filler is fumed silica.

25. Use of the adhesive composition according to any one of claims 20 to 24 for treating uncured rubber materials.

26. The use according to claim 25, wherein the uncured rubber material is a shoe rubber outsole.

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