ADHESIVE SYSTEM TO INCREASE THE ADHESION BETWEEN A DEVICE AND A USER'S SKIN

Description

[0001] The invention relates to an adhesive system for increasing the adhesion between a device and the skin of a user, a method for producing an adhesive effect, a kit for an adhesive system and the use of an adhesive system, a first coating component and a second coating component.

[0002] The use of resins to increase the adhesion between a device and the palm of a user is well known, for example, in handball. Natural resin is most commonly used in handball to increase the ball's grip and thus enable better ball control. However, depending on the region, synthetic resin can also be used. Natural resin is characterized by its particularly high stickiness. However, natural resin is difficult to remove from skin and clothing, which requires the use of special cleaning agents. Contact between the ball and the hall floor also leads to a transfer of the resin to the hall floor, which then requires complex and expensive cleaning. Although synthetic resin can be removed relatively easily with mild cleaning agents, the adhesive effect is significantly lower.

[0003] Alternatively, a device can be coated with an acrylate that possesses PSA (pressure-sensitive adhesive) properties. This initially creates an adhesive effect between the device and the skin. However, this adhesive effect quickly diminishes as dust accumulates on the sticky surface.

[0004] Other solutions include modifying the surface material of a piece of sports equipment, as described in US 2016 / 0310802 A1, for example. However, modified surfaces can wear out over time and, in the worst case, violate competition rules.

[0005] The application of adhesive pads with a non-slip outer surface to parts of the hand is also known in the art and is described, for example, in GB 2 382 762 A or EP 3 260 510 A1. However, such pads have the disadvantage that they can come off during play. Removing the adhesive pads is painful and can cause skin irritation. Furthermore, the use of such pads can violate competition rules.

[0006] It is therefore an object of the invention to overcome the disadvantages of the prior art.

[0007] In particular, it is an object of the invention to provide an adhesive system that enables very good adhesion between a device and the skin of a user without leaving any sticky residue. A further object of the invention is to provide a skin-friendly adhesive system.

[0008] These objects are achieved by the devices, methods, and uses defined in the independent patent claims. Further embodiments are set forth in the dependent patent claims.

[0009] The invention relates to an adhesive system for increasing the adhesion between a device, in particular a ball, and the skin of a user. The adhesive system comprises a first coating component, preferably a device coating component for application to at least part of the device, and a second coating component, preferably a skin coating component for application to at least part of the user's skin, in particular the inside of a palm or a fingertip. The first coating component and the second coating component each have a surface tack of > 35 cm, preferably > 40 cm, according to the rolling ball test according to ASTM D 3121-06. Upon contact of the first coating component with the second coating component, an adhesion of between 2 and 20 N / 25 mm is required, preferably an adhesion of between 2.5 and 15 N / 25mm, more preferably an adhesion between 5 and 12 N / 25mm, even more preferably between 6 and 10 N / 25mm, particularly preferably between 7 and 9 N / 25mm, according to the T-Peel test.

[0010] Such an adhesive system has surprisingly shown that bringing the first coating component into contact with the second coating component results in strong adhesion, allowing the device to adhere to the skin without great effort. At the same time, however, there is essentially no adhesive transfer from the device to the skin and vice versa. Since both coating components are non-sticky, hardly any dust or other foreign matter adheres to the hands or the devices.

[0011] One advantage of the adhesive system according to the invention is that the respective coating component can be applied precisely to the areas of the device and the skin where the desired adhesive effect is desired. This saves on adhesive material, while also avoiding unnecessary weight on either the device or the skin.

[0012] The device could be a handball, for example. Other sports equipment, such as a javelin, a pole vault, a relay baton, a gymnastic bar, or a tennis racket, are also conceivable. Musical instruments, tools, walking aids, or household appliances are also conceivable.

[0013] The first coating component can be a dispersion, preferably a polyurethane dispersion. Since the durability of polyurethanes is increased by the addition of crosslinkers, a crosslinker, such as an isocyanate, can also be added to the first coating component.

[0014] The first coating component may further comprise a wetting agent, which ensures sufficient wetting on, for example, artificial handball leather. Water may be added to the dispersion to reduce the viscosity so that the coating component can be applied evenly to the device.

[0015] Alternatives to a polyurethane dispersion include other compounds with cold-sealing properties, such as, but not limited to, polyisoprene, polyethylene vinyl acetate or polychloroprene.

[0016] Such a coating ensures adhesion between the first coating component and the second coating component comparable to commercially available handball resin. The coating itself is grippy but not sticky. Dirt and dust hardly adhere to a device coated with the first coating component. At the same time, it is compatible with almost all materials without attacking them. Essentially, there is no transfer of the first coating component to the environment. When the first coating component is used to coat a handball, the coating component is therefore essentially not transferred to the hall floor.

[0017] Depending on the application, the first coating component may also comprise an acrylate dispersion, a polyisoprene dispersion, a polyethylene-vinyl acetate dispersion, a polychloroprene dispersion, or mixtures thereof. These dispersions may be present with or without conventional crosslinking systems. Sulfur-containing compounds, for example, can serve as crosslinking systems for polyisoprene dispersions.

[0018] In principle, the first coating component can be optimized for adhesion to the corresponding surface by adding additives.

[0019] The second coating component may comprise a polyurethane dispersion and at least one additive. The additive may be selected from the group consisting of: polyvinylpyrrolidone, copolymers thereof, or modified polyvinylpyrrolidone; acrylate dispersions; dispersions and solutions of sugar-based raw materials, in particular pectins, gum arabic, cellulose derivatives, or rubber; other polyurethane dispersions; silane additives; silicone, or mixtures thereof.

[0020] For example, polyvinylpyrrolidone ensures that the second coating component adheres to the skin, while the polyurethane dispersion ensures adhesion between the skin and the second coating component. The other additives mentioned above can be used alternatively or in addition to polyvinylpyrrolidone.

[0021] Since the second coating component is intended for application to the skin, the additives must be skin-compatible and toxicologically safe.

[0022] The first and second coating components are preferably matched to each other in order to achieve optimal adhesion between the coating components.

[0023] At least one of the coating components can be alcohol-based. Alcohol-based coatings reduce drying time compared to water-based coatings. Another aspect of the invention relates to a method for creating an adhesive effect between a device and the user's skin using an adhesive system, preferably an adhesive system as described above. The method comprises the steps: Providing a first coating component, applying the first coating component to at least a part of a device, preferably a handball, drying the first coating component, providing a second coating component, applying the second coating component to at least a part of the user's skin, preferably an inner palm or a fingertip, drying the second coating component.

[0024] Both coating components each have a surface tackiness >35 cm, preferably > 40 cm according to the rolling ball test according to standard ASTM D-3121 06.

[0025] The procedure further includes the following step: Bringing the at least partially coated device into contact with the at least partially coated skin.

[0026] Upon contact of the first coating component with the second coating component, an adhesion between 2 and 20 N / 25 mm, preferably an adhesion between 2.5 and 15 N / 25 mm, more preferably an adhesion between 5 and 12 N / 25 mm, even more preferably between 6 and 10 N / 25 mm and particularly preferably between 7 and 9 N / 25 mm, according to the T-peel test, is achieved.

[0027] The low tackiness is also advantageous during use of the coating components, for example, when wearing a coating component on part of the palm of a hand: Transfer of the coating component to clothing, other objects, or dust contamination is virtually nonexistent. Adhesion is only achieved when the coating components are brought together. This adhesion enables the secure holding and handling of a device. In this process, there is essentially no transfer of one coating component to the other.

[0028] As described above, the device can be another piece of sports equipment, such as a javelin, a pole vault baton, a relay baton, a gymnastic bar, or a racquet sports racket. It is also conceivable that the device is a musical instrument, a tool, a walking aid, a household appliance, or an everyday object such as a mobile phone.

[0029] The first coating component and the second coating component are preferably configured as described above. The coating components can be applied using an application aid or by hand. Application aids include, for example, spray cans, roll-on pens, sponge applicator tubes, stamp pads, glue sticks, or brushes.

[0030] The first coating component and the second coating component can be liquid, gel-like or in the form of a paste, depending on the type of application and use.

[0031] The layer thickness of the freshly applied first and second coating components before drying is preferably between 5 and 100 µm, preferably 35 and 70 µm, and most preferably 55 and 65 µm.

[0032] The drying time of the first coating component can be between 25 and 35 minutes, preferably 30 minutes. The drying time of the second component can be between 2 and 15 minutes, preferably 5 and 10 minutes. The drying times can be shortened by additives, drying techniques, or coating techniques.

[0033] The application of the first and / or second coating component may be repeated at least once to ensure a lasting adhesion effect.

[0034] A further aspect of the invention relates to a kit for an adhesive system, in particular for an adhesive system as described above, for creating an adhesive effect between a device and the skin of a user. The kit comprises a first coating component for application to the device and a second coating component for application to the skin, as well as instructions for using the coating components, in particular in a method as described above. Optionally, the kit can have an application aid for the first and / or second coating component.

[0035] The coating components and optional application aids can be designed as previously described.

[0036] The kit has the advantage of including all components of the adhesive system to achieve optimal adhesion results. As a kit, the individual components can be easily stored and transported together, ensuring none of them are forgotten or lost.

[0037] The kit may also include a cleansing lotion. This allows for easy removal of the coating components from the user's skin or the device. Ideally, the cleansing lotion is specifically formulated for removing the coating components while also being skin-friendly. Different cleansing lotions for the first and second coating components may also be included in the kit.

[0038] Another aspect relates to the use of an adhesive system as previously described to create an adhesive effect between a device and the skin of a user.

[0039] A further aspect also relates to the use of a first coating component in an adhesive system, preferably as described above, together with a second coating component for producing an adhesive effect between a device and the skin of a user.

[0040] A further aspect also relates to the use of a second coating component in an adhesive system, preferably as described above, together with a first coating component for creating an adhesive effect between a device and the skin of a user. T-PEEL TEST The T-Peel test is carried out as follows:

[0041] The test strips coated with the coating components are cut from a representative sample of the material (a 22 µm thick polyester film coated with the coating component). The strips are 25 mm wide and 150 mm long in the grain direction. The cut must be clean and straight. Six test strips are provided for each coating component.

[0042] The test conditions should be as follows: 23°C ± 2°C and 50% ± 5% relative humidity. All test strips must be air-conditioned for at least 12 hours before testing.

[0043] During the test procedure, approximately 100 mm of the test strip is adhered to the test material using light finger pressure. The samples are then rolled twice in both directions using a FINAT standard 2 kg pressure roller at a speed of 10 mm / second. The bonded test strips are allowed to climatize for 20 minutes. The test strip coated with the second coating component is clamped in the upper clamp of the tensile testing machine, and the test strip coated with the first coating component is clamped in the lower clamp, creating a peel angle of 180°C. The test strip is then pulled apart at a speed of 300 mm / min.

[0044] Unless conflicting, ASTM Standard D 1876-01 should be used for additional information regarding the T-Peel test. In the event of conflicting information, the above information takes precedence. EXAMPLE 1: Application area handball PRODUCTION AND COMPOSITION OF THE COATINGS Device coating component

[0045] The equipment coating component is applied to the handball to maintain adhesion between the skin and the handball. Composition:

[0046] Raw materials Proportion [wt%] composition Example Polyurethane dispersion Baymedix AD111 from Covestro 85-95 Deionized water n / a 5-15 wetting agent Surfynol PSA 336 0-1

[0047] Water and wetting agent are added to the PU dispersion, then the three ingredients are mixed together by stirring. Skin coating components:

[0048] The skin coating component is applied to the hand to maintain adhesion between the handball and the hand. Skin coating component 1 Composition:

[0049] raw material Proportion [wt%] composition Example Aqueous polyvinylpyrrolidone (PVP) solution, 20%, K-value: 90 “Luvitec K90 solution approx. 20%” from BASF 40-60 Polyurethane dispersion (PUD), 50%, pH: 6-9 Baymedix AD111 from Covestro 60-40

[0050] The PVP solution is added to the PU dispersion, then the two ingredients are mixed together by stirring. Skin coating component 2 Composition:

[0051] raw material Proportion [wt%] composition Example Acrylate dispersion "Collano DP 7011" by Collano 5-20 Polyurethane dispersion (PUD), 50%, pH: 6-9 Baymedix AD111 from Covestro 80-95

[0052] The acrylate dispersion is added to the PU dispersion, then the two ingredients are mixed together by stirring. APPLICATION OF COATINGS Application of device coating component:

[0053] The equipment coating component is applied to a handball using a brush roller and then allowed to dry for 30-35 minutes. The drying time of the ball coating component can be influenced by the addition of additives, the drying method, or the type of coating. The layer thickness of the dried ball coating achieved with the brush roller is between 30 and 50 µm. Application of skin coating component:

[0054] The skin coating component is applied to fingertips and palms using a brush and then allowed to dry for 3-10 minutes. The drying time of the skin coating component can be influenced by the addition of additives, the drying method, or the coating type. When the coating method described above is used, the layer thickness of the dried skin coating is between 11 and 66 µm. COMPARISON OF COATING COMPONENTS TO HANDBALL RESIN

[0055] Various formulations were tested for adhesive transfer, surface tack, and adhesion. The composition of the ball coating component was kept constant, while the composition of the skin coating component varied. The handball resin "G-Resin for Handball," manufactured by Molten Europe GmbH, was used as a reference. Composition of the formulations (in percent by weight):

[0056] Handball resin (resin) Ball coating (BB) Skin coating 1 (H1) Skin coating 2 (H2) PUD 91.9 50 80 Aqueous PVP solution 50 Acrylate dispersion 20 wetting agent 0.8 Water 7.3 handball resin 100 1. Ball coating component (BB) and skin coating component 1 (H1) Adhesive transfer:

[0057] To determine the extent to which an adhesive leaves residues on other surfaces, the "Finger Grip Test" test method was developed. Skin (in this case, the fingertip of a test subject's right index finger) and artificial handball leather are coated with the coatings to be tested. The fingertip is cleaned with isopropanol before application, and the coating is allowed to air dry for three to five minutes at room temperature. The ball coating is applied to the handball leather using a squeegee with a coating weight of 2.5 g / m², and the coated substrate is dried for at least 30 minutes at 50°C.

[0058] Under the influence of force (20 to 25 N), the fingertip and the ball are pressed against each other for 10 seconds and then the finger is rolled sideways off the (coated) synthetic leather.

[0059] The adhesive transfer is assessed qualitatively.

[0060] The adhesive transfer of H1 and BB is compared with the adhesive transfer of resin using a finger grip test. Results:

[0061] criterion Both sides of the Harz Both sides BB One page BB one page H1 Stickiness of individual surface +++ + + Adhesion between coated surfaces +++ +++ +++ Adhesive transfer +++ +++ - Cleaning effort +++ + - Legend: +++ very large, + small, - not present Liability:

[0062] The adhesion between H1 and BB was compared with the adhesion of resin using a T-peel test (as previously described). For this purpose, the coating components BB and H1 were applied to a 22 µm thick polyester film (carrier material) using a doctor blade and dried at 50°C for 30 minutes. The resulting layer thicknesses were 29±3 µm and 20±2 µm, respectively. Resin was dissolved in toluene (mixing ratio resin:toluene 2:1), then applied to a 22 µm thick polyester film using a doctor blade and dried at 50°C for 15 minutes. The resulting layer thickness was 20±4 µm. The higher T-peel values ​​between H1 and BB can be explained by the different types of failure; resin is inherently softer and therefore more prone to cohesive failure. Results:

[0063] system Adhesion [N / 25mm] BB vs. HL coating 5 - 7 (Adhesive failure between device coating and skin coating. In individual cases, adhesive failure to the carrier material) Resin vs. resin coating 2.5 - 3 (cohesive failure) Surface stickiness:

[0064] The surface tackiness of BB and H1 was compared with that of resin using a rolling ball test according to ASTM 3121-06.

[0065] For this purpose, the coating components BB and H1 were applied to a 22 µm thick polyester film using a doctor blade and dried at 50°C for 30 minutes. The resulting layer thicknesses were 29±3 µm and 20±2 µm, respectively. Resin was dissolved in toluene (mixing ratio resin:toluene 2:1), then applied to a 22 µm thick polyester film using a doctor blade and dried at 50°C for 15 minutes. The resulting layer thickness was 20±4 µm.

[0066] The results in the table below show that H1 and BB have lower surface tackiness than resin. Results:

[0067] system Rolling Ball [cm] H1 >40 BB >40 resin 26 - 31 2. Ball coating component (BB) and skin coating component 2 (H2)

[0068] In addition to PVP, other systems were also considered as skin-adherent components of the skin coating component. For example, films made of acrylate dispersions with PSA properties are known to exhibit good skin adhesion.

[0069] Adhesive transfer, surface tack, and adhesion of formulation H2 were determined as previously described. For this purpose, coating components BB and H2 were applied to a 22 µm thick polyester film using a doctor blade and dried at 50°C for 30 minutes. The resulting film thicknesses were 29±3 µm and 30±3 µm, respectively.

[0070] Due to the low acrylate concentration, the surface tackiness of H2 does not increase significantly compared to that of H1. The adhesion between H2 and BB is also comparable to that between H1 and BB (see table below). Results surface tack and adhesion of BB and H2:

[0071] Test method / [unit] Value Rolling Ball Test / [cm] >40 T-Peel Test / [N / 25mm] 7 - 8.5 (adhesion failure between ball coating and skin coating. In some cases also adhesion failure to the carrier material)

[0072] However, the acrylate concentration is too low to generate sufficiently high skin adhesion; upon contact, H2 is transferred to the BB. Higher acrylate concentrations would be associated with increased surface tackiness, which would not be within the scope of the invention. Comparison of additives: H1 vs. H2

[0073] criterion Both sides handball resin One page BB One page BB One page Hl One page H2 Stickiness of individual surface +++ + + Adhesion between coated surfaces +++ +++ +++ Adhesive transfer +++ - + Cleaning effort +++ - + Legend: +++ very large, + small, - not present EXAMPLE 2: Application area pole vault

[0074] The equipment coating component (BB) mentioned in Example 1 is applied to the upper part of a fiberglass pole for pole vaulting using a brush roller and allowed to air dry for 45 minutes. The layer thickness is between 40 and 70 µm.

[0075] The skin coating component (H1) mentioned in Example 1 is applied to the palm of the pole vaulter's hand using a brush and allowed to air dry for 10 minutes. The layer thickness is between 11 and 66 µm.

[0076] Adhesive transfer, surface tack, and adhesion of the formulation were qualitatively assessed in comparison to tree resin, grip tapes with and without magnesia, adhesive grip tapes, and spray adhesive.

[0077] The formulation has proven to be very adhesive, especially compared to grip tape and / or magnesia. Nevertheless, it also allows for controlled pushing and releasing of the pole during the final flight phase of a pole vault. Compared to tree resin, the advantages are related to reduced surface stickiness. In particular, the coating components simplify handling and reduce contamination by dust and other interfering particles. Thanks to the thin application layer, the uniform pole diameter required by competition rules is maintained. EXAMPLE 3: Application area e-sports

[0078] The device coating component (BB) mentioned in Example 1 is applied to the joystick elements of a game console controller using a brush and allowed to air dry for 25 minutes. The layer thickness is between 30 and 60 µm.

[0079] The skin coating component (H1) mentioned in Example 1 is applied to the e-athlete's fingertips using a brush and allowed to air dry for 10 minutes. The layer thickness is between 11 and 66 µm.

[0080] Even with a thinner application layer, the formulation has a positive effect on the precise timing and spatial execution of commands, ultimately increasing the player's performance. Hand fatigue is also reduced during extended gaming sessions. Unlike common "gamer gloves" or anti-slip patches that are applied to the fingertips, the adhesive system is comfortable to wear. Compared to "Gamer Grip," which, similar to magnesia, dries the skin and prevents perspiration, the adhesive effect is superior.

Claims

1. An adhesive system for increasing the adhesiveness between a device, in particular a ball, and the skin of a user, comprising a first coating component for application to at least a part of the device and a second coating component for application to at least a part of the skin, in particular an inner side of a palm or a fingertip, of the user, wherein the first coating component and the second coating component each have a surface tackiness > 35 cm, preferably > 40 cm, according to the rolling ball test according to standard ASTM D 3121-06, characterized in that upon contact of the first coating component with the second coating component an adhesion between 2 and 20 N / 25mm, preferably an adhesion between 2.5 and 15 N / 25mm, more preferably an adhesion between 5 and 12 N / 25mm, even more preferably between 6 and 10 N / 25mm, particularly preferably between 7 and 9 N / 25mm, can be achieved according to the T-Peel test.

2. The adhesive system according to claim 1, wherein the first coating component comprises a dispersion, preferably a polyurethane dispersion.

3. The adhesive system according to claim 1, wherein the second coating component comprises a dispersion of polyurethane and at least one additive, wherein the additive is selected from the group consisting of: Polyvinylpyrrolidone; copolymers of polyvinylpyrrolidone; modified polyvinylpyrrolidone; acrylate dispersions; dispersions and solutions of sugar-based raw materials, in particular pectins, gum arabic, cellulose derivatives or rubber; other polyurethane dispersions; silane additives; silicone or mixtures thereof.

4. A method of creating an adhesive effect between a device and the user's skin by means of an adhesive system according to any one of claims 1 to 3, comprising the steps of: - i) Providing a first coating component, ii) applying the first coating component to at least a part of a device, preferably a handball, iii) drying the first coating component, iv) providing a second coating component, v) applying the second coating component to at least a part of the user's skin, preferably a palm side or a fingertip, vi) drying the second coating component, wherein both coating components each have a surface tackiness of> 35 cm, preferably > 40 cm, according to the rolling ball test according to standard ASTM D-3121 06, - Bringing the at least partially coated device into contact with the at least partially coated skin, characterized in that upon contact of the first coating component with the second coating component, an adhesion between 2 and 20 N / 25 mm, preferably an adhesion between 2.5 and 15 N / 25 mm, more preferably an adhesion between 5 and 12 N / 25 mm, even more preferably between 6 and 10 N / 25 mm and particularly preferably between 7 and 9 N / 25 mm, is achieved according to the T-peel test.

5. The method according to claim 4, wherein the layer thickness of the applied and dried first coating component and second coating component is between 5 and 100 µm, preferably 15 and 50 µm, and most preferably 18 and 32 µm.

6. The method according to any one of claims 4 or 5, wherein the application of the first coating component and / or the second coating component is repeated.

7. A kit for an adhesive system according to any one of claims 1 to 3, for creating an adhesive effect between a device and a user's skin, comprising - a first coating component for application to the device, - a second coating component for application to the skin, wherein the first coating component and the second coating component each have a surface tackiness > 35 cm, preferably > 40 cm, according to the rolling ball test according to standard ASTM D 3121-06, wherein upon contact of the first coating component with the second coating component an adhesion between 2 and 20 N / 25 mm, preferably an adhesion between 2.5 and 15 N / 25mm, more preferably an adhesion between 5 and 12 N / 25mm, even more preferably between 6 and 10 N / 25mm, particularly preferably between 7 and 9 N / 25mm, can be achieved according to the T-Peel Test; - Application instructions for the use of the coating components in a method according to any one of claims 4 to 6, - optional: an application aid; for the first coating component and / or second coating component.

8. The kit according to claim 7, wherein the kit additionally comprises a cleansing lotion.

9. Use of an adhesive system according to any one of claims 1 to 3, for creating an adhesive effect between a device and the skin of a user.

10. Use of a first coating component for application to at least a part of the device in an adhesive system according to any one of claims 1 to 3, together with a second coating component for creating an adhesive effect between a device and the skin of a user.

11. Use of a second coating component for application to at least a portion of the skin in an adhesive system according to any one of claims 1 to 3, together with a first coating component for creating an adhesive effect between a device and the skin of a user.