High-strength cyanoacrylate tape

Abstract

The present invention relates to a curable composition comprising a curable cyanoacrylate component and at least one thermoplastic polyurethane (TPU) component. The composition is non-flowable at room temperature (25°C) and is suitable for use as, for example, a tape-like adhesive composition.

Description

[Technical Field]

[0001] The present invention relates to a curable cyanoacrylate composition that is non-flowing at room temperature (25°C) and is suitable for use as an adhesive composition, such as in the form of a tape. [Background technology]

[0002] Known solid cyanoacrylate monomers at room temperature include phenylethyl cyanoacrylate, ethylhexyl cyanoacrylate, and hexadecyl cyanoacrylate. These solid cyanoacrylate monomers can be used to prepare stick and tape-type cyanoacrylate products. However, compositions based on these monomers perform inferiorly to compositions containing conventional liquid cyanoacrylate monomers at room temperature across a certain range of metrics. Furthermore, solid cyanoacrylate monomers are typically expensive, difficult to synthesize, and are often non-standard, specialized chemicals.

[0003] The cyanoacrylate tapes previously developed by Henkel were based on monomers that are solid at room temperature, such as phenylethyl cyanoacrylate. However, using solid cyanoacrylate monomers in the manufacture of adhesive tapes prohibits their use as "instant adhesive" tapes, negating the main advantages of using cyanoacrylate as an instant adhesive.

[0004] Liquid cyanoacrylate monomers diffuse well throughout the bulk and cure faster at room temperature than solid cyanoacrylate monomers.

[0005] However, developing tapes based on standard liquid cyanoacrylate monomers is challenging. This is not only due to the inherent reactivity of the cyanoacrylate monomers themselves with film-forming agents, but also because materials with sufficient structural integrity are required to achieve proper film formation.

[0006] In the patent literature, the following document demonstrates adhesive compositions formulated for use in tape form.

[0007] U.S. Patent Application No. 2015 / 0107761 discloses a tape comprising a curable film on a release substrate and / or carrier substrate. The curable film comprises at least one specific cyanoacrylate monomer and at least one film-forming (co)polymer.

[0008] U.S. Patent No. 5,147,938 discloses an adhesive transfer tape based on a polymer adhesive composition containing a pressure-sensitive acrylate copolymer.

[0009] U.S. Patent No. 20060029810 discloses an adhesive transfer tape comprising a pressure-sensitive adhesive composition based on a liquid epoxy resin that cures at high temperatures.

[0010] International Publication No. 2003 / 020841 discloses a pressure-sensitive adhesive composition comprising an acrylic copolymer and at least two tackifiers. This composition can be used to manufacture pressure-sensitive adhesive tapes.

[0011] It would be advantageous to develop an adhesive tape that achieves instant bonding without requiring heating under pressure. [Prior art documents] [Patent Documents]

[0012] [Patent Document 1] U.S. Patent Application No. 2015 / 0107761 [Patent Document 2] U.S. Patent No. 5147938 [Patent Document 3] U.S. Patent No. 20060029810 [Patent Document 4] International Publication No. 2003 / 020841 [Overview of the project] [Means for solving the problem]

[0013] In one aspect, the present invention is (i) A curable cyanoacrylate component, (ii) at least one thermoplastic polyurethane (TPU) component, A curable composition comprising, The aforementioned at least one TPU component (ii) has a mass-average molar mass M of 40,000 to 80,000. W It has, The at least one TPU component (ii) is based on a polyol based on at least one diol or dicarboxylic acid, the at least one diol or dicarboxylic acid having 6 carbon atoms (C6) in its main chain, and furthermore, each of the diols or dicarboxylic acids has more than 10 carbon atoms (>C) in its main chain. 10 ) does not have, The curable composition comprises the presence of at least one TPU component (ii) in an amount exceeding about 50% by weight, where the weight percentage is based on the total weight of the composition.

[0014] The composition of the present invention is non-flowing at room temperature (25°C) and is suitable for use, for example, as a tape-like adhesive composition. The composition can be applied onto a release liner. For example, an interliner layer or a liner with different release values ​​may be used. The composition can be applied using a suitable solvent, for example, by casting it onto the liner from a suitable solvent.

[0015] The curable cyanoacrylate component (i) may be selected from the group including ethyl cyanoacrylate, butyl cyanoacrylate, β-methoxycyanoacrylate, and combinations thereof.

[0016] The curable cyanoacrylate component (i) may be present in the curable composition in an amount of about 10% to about 35% by weight, where the weight percentage is based on the total weight of the composition.

[0017] At least one TPU component (ii) may be present in the curable composition in an amount of about 65% to about 85% by weight, based on the total weight of the composition.

[0018] In some embodiments, at least one TPU component (ii) has a glass transition temperature of about -60°C to about -5°C, such as about -50°C to about -10°C.

[0019] Preferably, at least one TPU component (ii) has a glass transition temperature of about -55°C to about -20°C, such as about -50°C to about -30°C.

[0020] The TPU component (ii) is based on a polyol based on at least one diol or dicarboxylic acid having 6 carbon atoms (C6) in the main chain.

[0021] The TPU component (ii) may be based on a polyol that is also based on one or more additional diols or dicarboxylic acids, provided that none of the diols or dicarboxylic acids have more than 10 carbon atoms (>C 10 ) in their main chain.

[0022] In some embodiments of the present invention, at least one TPU component (ii) includes a polyester segment.

[0023] Preferably, the TPU component (ii) includes a polyester segment based on at least one of a C6 diol or a C6 carboxylic acid.

[0024] At least one TPU component (ii) may be based on a polyester polyol formed from a C6 dicarboxylic acid and either 1,6 - hexanediol or 1,4 - butanediol.

[0025] Preferably, at least one TPU component (ii) is based on a (co)polyester of hexanedioic acid and one of 1,4-butanediol or 1,6-hexanediol, wherein the (co)polyester has a melting point of about 50 to 80°C and an OH value of less than about 0.5%, for example less than about 0.1% (measured according to standard procedure DIN 53240-2).

[0026] In some embodiments, the composition contains only one TPU component.

[0027] In some embodiments, the composition of the present invention may contain two or more TPU components.

[0028] Preferably, if the composition of the present invention contains two or more TPU components, each present TPU component has a mass-average molar mass M of 40,000 to 80,000. W Preferably, each TPU component is based on a polyol based on at least one diol or dicarboxylic acid having six carbon atoms (C6) in its main chain.

[0029] The composition of the present invention may further include one or more additional TPU components different from the above-mentioned at least one TPU, provided that the one or more additional TPUs have more than 10 carbon atoms (>C) in their main chain. 10 It is not based on polyols that have a diol or dicarboxylic acid. Such additional TPUs may be present in amounts such that the total TPU content is up to about 95% by weight based on the total weight of the composition.

[0030] The compositions of the present invention may further contain at least one solvent. The use of a solvent may be beneficial, for example, for compounding or distribution purposes.

[0031] However, wherever weight percent is used, it is based on the total weight of the composition without the solvent.

[0032] In some embodiments, the present invention includes a solvent selected from the group comprising ethyl acetate, tetrahydrofuran, methyl ethyl ketone, cyclohexanone, and acetone.

[0033] Preferably, the present invention includes ethyl acetate as a solvent.

[0034] The present invention may further contain a stabilizer for the cyanoacrylate component.

[0035] In some embodiments, the cyanoacrylate component stabilizer is present in an amount of about 10 ppm to about 200 ppm, for example, about 25 ppm to about 100 ppm.

[0036] The stabilizer may be selected from boron trifluoride (BF3) or sulfur dioxide (SO2).

[0037] Preferably, the stabilizer is sulfur dioxide (SO2).

[0038] The present invention also relates to a tape comprising a curable composition according to the present invention and one or more release liners.

[0039] The tape of the present invention may be a transfer tape. The release liner may be used, for example, to transfer a curable composition in the form of a film to at least one substrate.

[0040] The tape of the present invention may exhibit adhesive properties at room temperature, and the curable composition of the article may adhere to at least one surface by applying gentle pressure to the tape. The cyanoacrylate component of the composition functions as an instant adhesive. Therefore, the composition of the present invention should adhere immediately to any compatible substrate.

[0041] In another aspect, the present invention also provides a method for preparing a curable composition, i) A step of forming a mixture by combining at least one thermoplastic polyurethane (TPU) component as defined in the present invention with a curable cyanoacrylate component and a solvent as defined in the present invention. ii) A step of applying the mixture from step (i) to the substrate by casting, optionally. iii) A step of evaporating the solvent or actively removing the solvent to form a curable composition in solid form. Regarding methods including

[0042] In some embodiments of this method, the substrate is a release liner.

[0043] In some embodiments of this method, the solvent is ethyl acetate.

[0044] At least one TPU component (ii) is present in the curable composition in an amount exceeding approximately 50% by weight, where the weight percentage is based on the total weight of the composition.

[0045] At least one TPU component (ii) is present in an amount equal to or greater than that of the curable cyanoacrylate component.

[0046] In the method of the present invention, the TPU component may be as described above for the composition of the present invention, including, for example, the case in which the TPU component includes polyester segments.

[0047] The present invention also relates to the curing form of the composition according to the present invention.

[0048] The present invention further relates to an assembly comprising two substrates bonded together by a cured form of the composition of the present invention.

[0049] A TPU component "based" on a specific polyol is one in which the polyol was used in the synthesis of the TPU component or which forms structural units within the TPU component. Similarly, a polyol "based" on a diol unit or dicarboxylic acid unit is one in which the diol unit or dicarboxylic acid unit was used in the synthesis of the polyol or which forms structural units within the polyol.

[0050] A TPU component suitable for use in the present invention is based on a polyol comprising at least one diol or dicarboxylic acid, wherein at least one of the diols or dicarboxylic acids has six carbon atoms (C6) in its main chain, and none of the diols or dicarboxylic acids have more than 10 carbon atoms (>C10) in their main chain. In accordance with the IUPAC definition, the term “main chain” as used herein refers to a straight chain in which all other chains, whether long or short or both, are considered to be pendants. For example, in 5-methyl-1,12-dodecanedioic acid, the carbon atoms traveling in a straight line from carbon 1 to carbon 12 constitute the main chain, and the carbon atom of the methyl group at position 5 is considered to be outside the main chain. Thus, 5-methyl-1,12-dodecanedioic acid has 12 carbon atoms in its main chain. Similarly, a polyester polyol comprising repeating elements formed from a main chain C4 diol and a main chain C6 or main chain C7 dicarboxylic acid, each having at least 10 or 11 carbon atoms (crosslinked by ester bonds), wherein at least one of the diol or dicarboxylic acid has more than 10 carbon atoms (>C) in the main chain. 10 It does not contain at least one diol or dicarboxylic acid based on a polyol characterized by having ).

[0051] Suitable thermoplastic polyurethanes (TPUs) for use as solidifying agents in the present invention include, for example, those formed from the reaction of a polyisocyanate compound with a polyol, which yield a TPU having a low glass transition temperature (Tg) of about -60°C to -5°C, for example, about -50°C to about -10°C. The glass transition temperature (Tg) can be easily determined by techniques well known in the art, such as differential scanning calorimetry. An example of a polyol suitable for carrying out the present invention is Pearlbond 106, which is a linear aromatic polyurethane having a melt flow index of 10-30 g / 10 min (170°C / 2.16 kg) (measured according to DIN 53.735), a melt viscosity of 1150 Pa·s (170°C / 2.16 kg) (measured according to DIN 53.735), a softening range of 62-66°C (measured according to MQSA 70A), a melting range of 85-110°C (measured according to MQSA 70A), a high crystallinity (measured according to MQSA 12B), and very high thermoplasticity (measured according to MQSA 68A). [Modes for carrying out the invention]

[0052] Surprisingly, it was found that using thermoplastic polyurethane (TPU) in combination with curable cyanoacrylate components (e.g., ethyl cyanoacrylate, butyl cyanoacrylate, β-methoxycyanoacrylate, or combinations thereof) in relatively high weight percentages (over approximately 50% by weight) based on the total weight of the composition resulted in the production of films with extremely high integrity.

[0053] The TPU used in the curable composition of the present invention is present in an amount exceeding approximately 50% by weight based on the total weight of the composition. Although not bound by any principle, this relatively high proportion of TPU in the composition is considered essential for achieving high film integrity.

[0054] TPU demonstrated excellent stability in various types of cyanoacrylate monomers.

[0055] TPUs possess mechanical properties that fall between those of thermoplastic and thermosetting materials. This is achieved through "virtual crosslinking" caused by hydrogen bonding between urethane groups on opposite polymer chains. This inter-chain hydrogen bonding gives these unique materials a variety of physical properties, which are visibly manifested as excellent elasticity and elongation.

[0056] These rubbery or elastic properties enable the manufacture of highly imperfect films.

[0057] Furthermore, TPU film-forming agents possess excellent tensile strength and elongation properties, offering superior advantages over other available film-forming agents.

[0058] It is believed that using liquid cyanoacrylate monomers results in better diffusion throughout the bulk compared to solid cyanoacrylate monomers, leading to faster curing at room temperature.

[0059] When TPU material is combined with liquid cyanoacrylate monomer, the resulting film not only has high internal structural integrity but also hardens immediately upon contact with a standard substrate.

[0060] A TPU component "based" on a specific polyol is one in which the polyol was used in the synthesis of the TPU component or which forms structural units within the TPU component. Similarly, a polyol "based" on a diol unit or dicarboxylic acid unit is one in which the diol unit or dicarboxylic acid unit was used in the synthesis of the polyol or which forms structural units within the polyol.

[0061] A TPU component suitable for use in the present invention is based on a polyol comprising at least one diol or dicarboxylic acid, wherein at least one of the diols or dicarboxylic acids has 6 carbon atoms (C6) in its main chain, and each of the diols or dicarboxylic acids has more than 10 carbon atoms (>C6) in its main chain. 10) characterized by not having. According to the IUPAC definition, the term "main chain" as used herein refers to a straight chain where all other chains, whether long or short or both, are considered pendant. For example, in 5-methyl-1,12-dodecanedioic acid, the carbon atoms that proceed straight from carbon 1 to carbon 12 constitute the main chain, and the carbon atom of the methyl group at the 5-position is considered to be outside the main chain. Thus, 5-methyl-1,12-dodecanedioic acid has 12 carbon atoms in the main chain. Similarly, a polyester polyol formed from a main chain C4 diol and a main chain C6 or main chain C7 dicarboxylic acid and containing repeating elements having at least 10 or 11 carbon atoms (crosslinked by ester bonds), respectively, does not contain a polyol based on at least one diol or dicarboxylic acid characterized by having more than 10 carbon atoms (>C 10 ) in the main chain of at least one of the diol or dicarboxylic acid.

[0062] Without being bound by any principle, it is considered that the use of a TPU component based on at least one diol or dicarboxylic acid characterized by having at least one of the diol or dicarboxylic acid having 6 carbon atoms in the main chain and neither of the diol or dicarboxylic acid having more than 10 carbon atoms (>C 10 ) in the main chain reduces the likelihood of undesirable crystallization.

[0063] >C 10 TPU based on diol or dicarboxylic acid is used in the preparation of a solid cyanoacrylate composition, and it is considered that the longer the polyol chain, the more the crystallization and subsequent solidification are promoted.

[0064] However, this crystallization process can be harmful during the preparation of the composition for use in an adhesive tape because it can cause opacity and affect the registration of components in the final assembly.

[0065] As used herein, the term “tape” refers to an article comprising a curable composition and one or more release liners.

[0066] As used herein, the terms “stabilizer” or “Lewis acid stabilizer” refer to a substance that stabilizes a curable cyanoacrylate component, for example, by inhibiting the premature polymerization of cyanoacrylate. Examples of such substances include boron trifluoride (BF3) or sulfur dioxide (SO2). Those skilled in the art will readily understand that other suitable stabilizers, such as another suitable Lewis acid, can be used to stabilize the curable cyanoacrylate component. Stabilizer solutions can be prepared using ethyl cyanoacrylate, β-methoxycyanoacrylate, or butyl cyanoacrylate as a stabilizer carrier, and these stabilizer solutions are disclosed to be suitable for adjusting the amount of stabilizer in a curable composition based on ethyl cyanoacrylate, β-methoxycyanoacrylate, or butyl cyanoacrylate, respectively.

[0067] The formulation of the compositions and products of the present invention can be achieved by mixing a thermoplastic polyurethane (TPU) component with a solvent and stirring at a high temperature. Preferably, the mixture is stirred at a high temperature, for example, about 65°C, using a melting blade at about 1330 rpm. The actual temperature used may vary depending on the melting point or solubility of the TPU used. Mixing is carried out for a sufficient amount of time for the TPU component to dissolve in the solvent, although this time may vary depending on the batch size. A stabilizer may be added at this stage. The curable cyanoacrylate component is then added to the composition. Although not bound by any principle, it is thought that adding the cyanoacrylate component later has a beneficial effect on the stability of the final product.

[0068] The adhesive formulation can optionally be applied to a substrate, such as a release liner, by casting. The substrate can optionally be left at a high temperature, such as approximately 60°C, for a certain period, for example, about 5 minutes, to facilitate solvent removal. After this period, the film thickness may be substantially less than the thickness of the coating in its wet state. Once the solvent has evaporated, rapid spooling may be performed to prevent dust particles or moisture from coming into contact with the film surface. [Brief explanation of the drawing]

[0069] Embodiments of the present invention will be described merely as examples with reference to the accompanying drawings.

[0070] [Figure 1] Figure 1 shows the results of tensile shear tests on several substrates using adhesive tapes prepared from the cyanoacrylate composition according to Example 1 of the present invention, providing a comparison of the performance of Example 1 and Durotac 9640. [Figure 2] Figure 2 shows the results of tensile shear tests on several substrates using adhesive tapes prepared from the cyanoacrylate composition according to Example 2 of the present invention, providing a comparison of the performance of Example 2 and Durotac 9640. [Figure 3] Figure 3 shows the results of tensile shear tests on several substrates using adhesive tapes prepared from the cyanoacrylate composition according to Example 3 of the present invention, providing a comparison of the performance of Example 3 and Durotac 9640. [Figure 4] Figure 4 shows the results of a T peel test obtained using adhesive tapes prepared from the cyanoacrylate composition according to the present invention, and provides a comparison of their performance with that of Durotac 9640. [Figure 5] Figure 5 shows the results of a side impact test using the composition according to the present invention, and provides a comparison of their performance with that of Durotac 9640. [Examples]

[0071] Compositions 1 to 3 of examples suitable for carrying out the present invention were prepared as detailed below.

[0072] Ethyl acetate solvent was placed in a suitable container, and Pearlbond 106, the TPU component, was added. The mixture was stirred and brought to a temperature of approximately 65°C. The TPU component was completely dissolved in about 1-2 hours under high shear mixing at 1330 rpm using a dissolution blade. Then, the boron trifluoride stabilizer was added, followed by the associated cyanoacrylate monomer.

[0073] Table 1, provided below, summarizes the compositions of Examples 1 to 3.

[0074] [Table 1]

[0075] Adhesive tapes suitable for carrying out the present invention were prepared using the compositions of Examples 1 to 3.

[0076] Each adhesive formulation was coated onto a silicone-treated polyester film (SRF122 / 75μm) available from PPI film. A wet coating thickness of 150 microns was used. After drying the film at 60°C for 5 minutes to facilitate the removal of the ethyl acetate solvent, the film thickness was approximately 60 μm. Once dry, the adhesive tape was transferred to the test substrate by lightly pressing it with a finger. This ease of transfer (instantaneous adhesion) is achieved by the presence of the liquid monomer.

[0077] Table 2, provided below, shows the weight percentage of each component in the compositions of Examples 1-3 after the solvent has been removed. The weight percentages are based on the total weight of the composition.

[0078] [Table 2]

[0079] Adhesive tapes prepared from the compositions of Examples 1-3 were subjected to several comparative tests, and their performance was evaluated in comparison to the control composition Durotac 9640. Durotac 9640 is a cyanoacrylate tape based on solid cyanoacrylate monomer and polyethylene / polyvinyl acetate film-forming agent. Tensile shear (across various substrates), T-peel (grit-blasted mild steel (GBMS)), and lateral impact tests were performed.

[0080] Figure 1 shows the results of a tensile shear test of the adhesive tape of the present invention using the composition of Example 1, which is based on butyl cyanoacrylate. Tensile shear tests were performed according to ASTM D1002 (2000). The tensile strength of the tape was measured across various substrates and compared with the tensile strength of DuroTac 9640. The adhesive was assembled at room temperature (25°C) and the test was performed after a further 24 hours at room temperature. In Figures 1-3, "SF" is used to report substrate failure, which occurs when the adhesion is stronger than the substrate, and the substrate is destroyed before adhesion. Since each tensile shear test was performed 5 times, if substrate failure was observed in, for example, 1 out of 5 experiments, then 20% of substrate failures are reported.

[0081] The adhesive tapes prepared using the composition of Example 1 showed significantly improved performance compared to Durotac 9640 across all tested substrates. The highest tensile shear values ​​measured for the composition of Example 1 were observed on PC (polycarbonate) and teak substrates.

[0082] Figure 2 shows the results of tensile shear tests using the adhesive tape of the present invention, which is based on the composition of Example 2, which is β-methoxycyanoacrylate. The tensile strength of the tape was measured across various substrates and compared with the tensile strength of Durotac 9640. The adhesive was assembled at room temperature (25°C) and the test was performed after a further 24 hours at room temperature.

[0083] The adhesive tape prepared in Example 2 showed significantly improved performance compared to DuroTac 9640 across almost all tested substrates, with DuroTac 9640 outperforming only when tested on aluminum. The highest tensile shear value was measured on a teak substrate. Figure 3 shows the results of tensile shear tests using the adhesive tape of the present invention with the composition of Example 3. Example 3 is also based on β-methoxycyanoacrylate, but the cyanoacrylate component is present in a lower proportion than in Example 2. The tensile strength of the tape was measured across various substrates and compared to the tensile strength of DuroTac 9640. The adhesive was assembled at room temperature (25°C) and tested after a further 24 hours at room temperature.

[0084] The adhesive tapes prepared using the composition of Example 3 showed improved performance compared to Durotac 9640 across all tested substrates. Here again, the highest tensile shear value was measured on a teak substrate.

[0085] The T-peel performance of tapes prepared using the compositions of Examples 1 to 3 was measured and compared with the control composition, Durotac 9640. The T-peel test was conducted according to ASTM D1876 (2010). The test was performed on a grit-blasted mild steel (GBMS) substrate using T-peel test specimens with a width of 25.4 mm and a length of 150 mm, and cured at room temperature (25°C) for 24 hours, or cured at room temperature for 24 hours and then further cured at 80°C for 20 minutes. The results of the T-peel test are shown in Figure 4.

[0086] Under curing conditions in both sets, all the compositions of the tested examples showed substantially improved performance compared to Durotac 9640. Excellent T-peel performance was demonstrated in all the compositions of the examples. The highest T-peel values ​​were achieved in Examples 1 and 2 when cured at room temperature for 24 hours. For all the compositions tested, T-peel performance was higher when cured at room temperature than when cured at 80°C for 20 minutes after curing at room temperature. However, even the lowest T-peel values ​​obtained for the compositions of the tested examples were several times higher than any values ​​observed for Durotac 9640.

[0087] The side impact performance of tapes prepared using the compositions of Examples 1 to 3 was measured and compared with the control composition, Durotac 9640. The side impact test was performed according to STM812. The test was conducted on a mild steel substrate, cured at room temperature (25°C) for 24 hours, or cured at room temperature for 24 hours followed by further curing at 80°C for 20 minutes. The results of the side impact test are shown in Figure 5.

[0088] All the compositions in the tested examples exhibited excellent lateral impact performance, significantly outperforming the control composition, Durotac 9640. Results obtained after curing at room temperature for 24 hours followed by further curing at 80°C for 20 minutes were comparable to those obtained when curing at room temperature only.

[0089] As used herein in relation to the present invention, the terms “comprises / comprising” and “having / including” are used to identify the presence of a described feature, integer value, process, or component, but do not preclude the presence or addition of one or more other features, integer values, processes, components, or groups thereof.

[0090] For clarity, certain features of the present invention described in relation to separate embodiments may be provided in combination in a single embodiment. Conversely, various features of the present invention described in relation to a single embodiment for brevity may also be provided individually or in any suitable subcombination.

Claims

1. (i) A curable cyanoacrylate component, (ii) at least one thermoplastic polyurethane (TPU) component, (iii) A stabilizer containing cyanoacrylate components in a concentration of 10 ppm to 200 ppm, A curable composition comprising, The at least one TPU component (ii) has a mass-average molar mass M of 40,000 to 80,000. Ｗ It has, The at least one TPU component (ii) is based on a polyester polyol formed from a C6 dicarboxylic acid and one of 1,6-hexanediol or 1,4-butanediol, The curable composition wherein the at least one TPU component (ii) is present in an amount of 65% to 85% by weight, where the weight percentage is based on the total weight of the composition.

2. The curable composition according to claim 1, wherein the cyanoacrylate component (i) is a liquid curable cyanoacrylate component.

3. The curable composition according to claim 1 or 2, wherein the cyanoacrylate component (i) is selected from the group comprising ethyl cyanoacrylate, butyl cyanoacrylate, β-methoxycyanoacrylate, and combinations thereof.

4. The curable composition according to any one of claims 1 to 3, wherein the cyanoacrylate component (i) is present in the curable composition in an amount of 10% to 35% by weight, the weight percentage being based on the total weight of the composition.

5. The curable composition according to any one of claims 1 to 4, further comprising a solvent selected from the group consisting of ethyl acetate, tetrahydrofuran, methyl ethyl ketone, cyclohexanone, and acetone.

6. The curable composition according to claim 5, wherein the solvent used is ethyl acetate.

7. The curable composition according to any one of claims 1 to 6, wherein the at least one TPU component (ii) has a glass transition temperature of -60°C to -5°C.

8. The curable composition according to any one of claims 1 to 7, wherein the at least one TPU component (ii) has a glass transition temperature of -55°C to -20°C.

9. A curable composition according to any one of claims 1 to 8, comprising a stabilizer of cyanoacrylate component in an amount of 25 ppm to 100 ppm.

10. The aforementioned stabilizer is boron trifluoride (BF ３ ) or sulfur dioxide (SO ２ A curable composition according to claim 1, selected from ).

11. The aforementioned stabilizer is sulfur dioxide (SO ２ The curable composition according to claim 1, which is the same as the one described in claim 1.

12. A curable composition according to any one of claims 1 to 11, provided in tape form.

13. A tape comprising a curable composition according to any one of claims 1 to 12 and one or more release liners.

14. A method for preparing a curable composition, i) A step of forming a mixture by combining at least one thermoplastic polyurethane (TPU) component according to any one of claims 1 to 12 with a curable cyanoacrylate component and a solvent according to any one of claims 1 to 12. ii) Optionally, apply the mixture from step (i) to the substrate by casting. iii) A step of evaporating the solvent or actively removing the solvent to form a curable composition in solid form, A method that includes this.

15. The method according to claim 14, wherein the substrate is a release liner.

16. The method according to claim 14, wherein the solvent is ethyl acetate.

17. A cured product of the curable composition according to any one of claims 1 to 12.

18. An assembly comprising two substrates bonded together by a cured product of a curable composition according to any one of claims 1 to 12.

Images