UV adhesive with controllable curing time

Abstract

The application provides a UV adhesive with controllable curing time, which comprises the following raw materials in parts by weight: 50-100 parts of alicyclic epoxy resin and 0.11-4 parts of a photoinitiator; wherein the photoinitiator comprises a cationic photoinitiator and an imidazole type accelerator; the mass of the imidazole type accelerator accounts for 0.95%-90% of the mass of the photoinitiator. The formula of the adhesive is reasonably set, the UV curing rate of the cationic photoinitiator is delayed by introducing the imidazole type accelerator, the collocation of the two can achieve the effect that the resin can be relatively slowly cured after preliminary curing under light irradiation even without light irradiation, and the curing time is prolonged; moreover, the UV curing time of the adhesive can be further regulated by controlling the content of the imidazole type accelerator, and the delayed curing of different time is realized, so that the operation time can be accurately controlled in the production and application process.

Description

Technical Field

[0001] This invention belongs to the field of adhesive technology, specifically, it relates to a UV adhesive with controllable curing time. Background Technology

[0002] UV-curable adhesives fall into two main categories: free-radical curing adhesives and cationic curing adhesives. They are environmentally friendly, single-component, easy to store, and have fast curing speeds, making them increasingly widely used in modern automated and large-scale production. Free-radical UV-curable adhesives have the fastest curing speed, but they suffer from oxygen inhibition, leading to surface stickiness and incomplete deep curing. They also exhibit significant curing shrinkage and poor long-term aging performance, making them unsuitable for opaque applications. Cationic UV-curable adhesives do not have oxygen inhibition issues and possess delayed curing properties, allowing them to be used in opaque applications. In bonding opaque materials, ordinary UV cationic curing adhesives have limited delay times; too short a time makes them difficult to handle and results in poor wetting of the non-adhesive interface, leading to decreased bond strength and making rework difficult. Therefore, solving the problems of limited delayed curing time and low bond strength in current adhesives is of significant research importance and application value. Summary of the Invention

[0003] The purpose of this invention is to provide a UV adhesive with controllable curing time, which can achieve relatively slow curing even in the absence of light after initial curing under light irradiation.

[0004] According to one aspect of the present invention, a UV adhesive with controllable curing time is provided, comprising the following raw materials in parts by weight: 50-100 parts of alicyclic epoxy resin and 0.11-4 parts of photoinitiator; wherein the photoinitiator comprises a first component and a second component, the first component being a cationic photoinitiator and the second component being an imidazole accelerator; the imidazole accelerator accounts for 0.95%-90% of the mass of the photoinitiator. The present invention rationally sets the adhesive formulation, introducing an imidazole accelerator to delay the UV curing rate of the cationic photoinitiator. The combination of the two enables the resin to continue curing relatively slowly even without light irradiation after initial curing under light, achieving the effect of extending the curing time. This facilitates the application of the adhesive provided by the present invention to opaque materials, simplifying process operations. Furthermore, by controlling the content of the imidazole accelerator, the UV curing time of the adhesive can be further controlled, achieving delayed curing at different times, allowing for more accurate control of operating time during production applications. Simultaneously, it ensures that the cured product obtained from this adhesive has excellent mechanical strength, crosslinking density, and adhesive properties.

[0005] Preferably, the imidazole accelerator includes at least one of alkyl imidazole, cyanoethyl imidazole, cyanoethyl imidazole salt, and triisocyanate imidazole.

[0006] Preferably, the alkylimidazolium includes 2-methylimidazolium, 2-ethyl-4-methylimidazolium, 2-undecylimidazolium, 2-heptadecylimidazolium, 1,2-dimethylimidazolium, 2-phenylimidazolium, 2-phenyl-4,5-dihydroxymethylimidazolium, 2-phenyl-4-methyl-5-hydroxymethylimidazolium, 2-phenyl-4-methylimidazolium, 2-phenylimidazolium-triisocyanate, 2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole, and 2-phenylimidazoline;

[0007] Preferably, cyanoethyl imidazole includes 1-cyanoethyl-2-methylimidazolium, 1-cyanoethyl-2-ethyl-4-methylimidazolium, 1-cyanoethyl-2-undecylimidazolium, and 1-cyanoethyl-2-phenylimidazolium.

[0008] Preferably, the cyanoethyl imidazole salt includes 1-cyanoethyl-2-phenylimidazolium trimellitate and 1-cyanoethyl-2-undecylimidazolium trimellitate;

[0009] Preferably, the triisocyanate imidazole includes 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-triazine isocyanuric acid adduct and 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-triazine.

[0010] Preferably, the imidazole accelerator is an alkylimidazolium. In this invention, alkylimidazolium exhibits good stability, and its combination with a cationic photoinitiator can effectively regulate the UV curing time of the adhesive. This allows for the regular control of the UV curing time by adjusting the content of the imidazole accelerator, avoiding the difficulty in accurately controlling the UV curing time due to large fluctuations or irregular changes.

[0011] Preferably, the cationic photoinitiator includes one or more of iodonium salts and thiodonium salts; wherein the mass ratio of imidazole accelerator to cationic photoinitiator is 0.01-0.1:0.1-3. In this invention, the specific cationic photoinitiator described above has good compatibility with the imidazole accelerator content described above, and the cationic photoinitiator has good stability. It allows for accurate control of the UV curing time of the adhesive by adjusting the content of the imidazole accelerator, thereby enabling the adhesive to complete curing within a convenient operating time without affecting production efficiency.

[0012] Preferably, the iodonium salt includes at least one of diarylhexafluoroantimony iodonium salt and diarylhexafluorophosphate iodonium salt;

[0013] Preferably, the thioonium salt includes at least one of triarylhexafluoroantimony thioonium salt and triarylhexafluorophosphate thioonium salt.

[0014] Preferably, the photoinitiator is triarylhexafluoroantimonylate thionium salt, and the imidazole accelerator is 2-ethyl-4-methylimidazolium. This invention employs a specific photoinitiator, which can delay the curing reaction while ensuring the resin system initially cures under the initiation of the photoinitiator. Furthermore, by controlling the amount of imidazole accelerator added, the UV curing time of the adhesive can be accurately controlled, thereby keeping the delayed curing time within a suitable range. This avoids inconvenience due to excessively short curing times or reduced production efficiency due to excessively long curing times.

[0015] Preferably, the alicyclic epoxy resin is at least one selected from 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexylmethyl ester, poly[(2-epoxyethylene)-1,2-cyclohexanediol]2-ethyl-2-(hydroxymethyl)-1,3-propanediol ether, tetrahydroindene diepoxide, 1,2-epoxy-4-vinylcyclohexane, 3,4-epoxycyclohexylmethyl methacrylate, 3,4-epoxycyclohexyl methacrylate, and vinylcyclohexene dioxide. This invention utilizes a specific alicyclic epoxy resin under the action of a specific photoinitiator to achieve UV curing. This allows for further delaying of the UV curing rate of the cationic photoinitiator while ensuring the adhesive properties of the cured product. It also enables precise control of the UV curing time of the adhesive by adjusting the content of imidazole accelerators.

[0016] Preferably, the raw materials of the UV adhesive with controllable delayed curing time further include active monomers, including oxetane monomers and / or vinyl ether monomers. In this invention, oxetane monomers and vinyl ether monomers are introduced as active monomers. Due to their active groups, they can improve the crosslinking density and bonding strength of the adhesive. Moreover, the low viscosity active monomers can act as diluents, resulting in a wider viscosity range for the formulated adhesive, which is beneficial for adapting to more application scenarios.

[0017] Preferably, the oxetane monomer is at least one selected from 3-ethyl-3-hydroxymethyloxetane, 3-ethyl-3-[(2-ethylhexyloxy)methyl]epoxybutane, 3,3'-(oxybis(methylene)bis(3-ethyl)oxetane, and 1,4-bis[(3-ethyl-3-oxetane-butylmethoxy)methyl]benzene. In this invention, the use of the aforementioned specific oxetane monomer provides moderate reactivity, avoiding excessively rapid curing of the adhesive due to high reactivity, which would result in a short curing time and negatively impact subsequent processing operations.

[0018] Preferably, the amount of oxetane monomer added is determined according to a mass ratio of 0-50:50-100 for the mass of oxetane monomer to alicyclic epoxy resin. This invention, by rationally setting the content of oxetane monomer, enables the adhesive to have a suitable viscosity, promoting a complete curing reaction; simultaneously, the aforementioned amount of added oxetane improves the adhesive strength and mechanical strength of the adhesive while ensuring delayed curing.

[0019] Preferably, the amount of oxetane monomer added is determined according to the ratio of mass of oxetane monomer to mass of alicyclic epoxy resin of 5-10:75-100.

[0020] Preferably, the amount of vinyl ether monomer added is determined according to the ratio of the mass of vinyl ether monomer to the mass of alicyclic epoxy resin as 0-20:50-100.

[0021] Preferably, the vinyl ether monomer is at least one selected from vinyl methyl ether, vinyl ethyl ether, vinyl n-propyl ether, vinyl isopropyl ether, vinyl tert-butyl ether, vinyl n-butyl ether, vinyl isobutyl ether, vinyl cyclohexyl ether, vinyl ethylene glycol ether, vinyl diethylene glycol ether, 4-hydroxybutyl vinyl ether, 2-ethylhexyl vinyl ether, diethylene glycol divinyl ether, divinyl-1,4-butanediol ether, triethylene glycol divinyl ether, and ethylene glycol monoallyl ether.

[0022] Preferably, the raw materials of the UV adhesive with controllable delayed curing time also include toughening resin;

[0023] Preferably, the raw materials of the UV adhesive with controllable delayed curing time also include fillers, thixotropic agents, and additives.

[0024] According to another aspect of the present invention, a method for preparing the above-mentioned UV adhesive with controllable curing time is provided, characterized by comprising the following steps: mixing an alicyclic epoxy resin, a cationic photoinitiator, an imidazole accelerator, and an active monomer, stirring until homogeneous, and then degassing under vacuum to obtain a UV adhesive with controllable curing time. Detailed Implementation

[0025] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions of this invention will be clearly and completely described below in conjunction with the embodiments of this invention. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this invention.

[0026] In the following examples, the main active ingredient of "CELLOXIDE 2021P" is 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexylmethyl ester; the main active ingredient of "CELLOXIDE 8010" is 3,3',4,4'-diepoxy)biscyclohexane; the main active ingredient of "OXT-101" is 3-ethyl-3-hydroxymethyloxetane; and the main active ingredient of "2E4MZ" is 2-ethyl-4-methylimidazole.

[0027] Example 1

[0028] This embodiment provides a UV adhesive, and the preparation method of this UV adhesive with controllable curing time includes the following steps:

[0029] (1) Prepare the raw materials for the UV adhesive with controllable curing time according to Table 1, mix them and stir evenly, and then degas them under vacuum to obtain the UV adhesive prepared by imidazole accelerator with a weight of 0.1 in this embodiment.

[0030] (2) Then, the weight parts of the imidazole accelerator 2E4MZ used are adjusted to 0.001, 0.01, 0.05, 0.5, 1, and 10, respectively. Other materials are prepared according to Table 1. The above operation is repeated to prepare the adhesive, thus obtaining the UV adhesive prepared by imidazole accelerators with weight parts of 0.001, 0.01, 0.05, 0.1, 0.5, 1, and 10 in this embodiment.

[0031] Table 1. Raw materials of the UV adhesive in Example 1

[0032]

[0033] Example 2

[0034] This embodiment refers to Example 1 for preparing a UV adhesive. The difference between this embodiment and Example 1 is that the imidazole accelerator used in the preparation of the UV adhesive in this embodiment is 1-cyanoethyl-2-undecylimidazole. Apart from the above difference, the materials and process operations used in this embodiment are strictly consistent with those in Example 1.

[0035] Example 3

[0036] This embodiment refers to Example 1 for preparing a UV adhesive. The difference between this embodiment and Example 1 is that the imidazole accelerator used in the preparation of the UV adhesive in this embodiment is 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-triazine. Apart from the above difference, the materials and process operations used in this embodiment are strictly consistent with those in Example 1.

[0037] Example 4

[0038] This embodiment refers to Example 1 for preparing a UV adhesive. The difference between this embodiment and Example 1 is that the alicyclic epoxy resin used in the preparation of the UV adhesive in this embodiment is bis((3,4-epoxycyclohexyl)methyl)adipate. Apart from the above difference, the materials and process operations used in this embodiment are strictly consistent with those in Example 1.

[0039] Example 5

[0040] This embodiment refers to Example 1 for preparing a UV adhesive. The difference between this embodiment and Example 1 is that the alicyclic epoxy resin used in the preparation of the UV adhesive in this embodiment is vinylcyclohexene diester. Apart from the above difference, the materials and process operations used in this embodiment are strictly consistent with those in Example 1.

[0041] Example 6

[0042] This embodiment refers to Example 1 for preparing a UV adhesive. The difference between this embodiment and Example 1 is that the raw materials used in preparing the UV adhesive in this embodiment do not include oxetane monomers. Apart from the above difference, the materials and process operations used in this embodiment are strictly consistent with those in Example 1.

[0043] Example 7

[0044] This embodiment refers to Example 1 for preparing a UV adhesive. The difference between this embodiment and Example 1 is that the oxetane monomer used in the preparation of the UV adhesive in this embodiment is 3,3'-[oxybis(methylene)]bis[3-ethyl]oxetane. Apart from the above difference, the materials and process operations used in this embodiment are strictly consistent with those in Example 1.

[0045] Example 8

[0046] This embodiment refers to Example 1 for preparing a UV adhesive. The difference between this embodiment and Example 1 is that the raw materials used in preparing the UV adhesive in this embodiment do not include vinyl ether monomers. Apart from the above difference, the materials and process operations used in this embodiment are strictly consistent with those in Example 1.

[0047] Comparative Example 1

[0048] This comparative example prepares a UV adhesive according to Example 1. The difference between this example and Example 1 is that the raw materials used in the preparation of the UV adhesive in this comparative example do not include imidazole accelerators. Apart from the above difference, the materials and process operations used in this comparative example are strictly consistent with those in Example 1.

[0049] Comparative Example 2

[0050] This comparative example prepares a UV adhesive according to Example 1. The difference between this example and Example 1 is that the alicyclic epoxy resin used in the preparation of the UV adhesive in this comparative example is replaced with bisphenol A type epoxy resin. Apart from the above difference, the materials and process operations used in this comparative example are strictly consistent with those in Example 1.

[0051] Comparative Example 3

[0052] This comparative example prepares a UV adhesive according to Example 1. The difference between this example and Example 1 is that the alicyclic epoxy resin used in the preparation of the UV adhesive in this comparative example is replaced with an epoxidized olefin epoxy resin. Apart from the above difference, the materials and process operations used in this comparative example are strictly consistent with those in Example 1.

[0053] Test Example 1

[0054] 1. Participants

[0055] This test example uses the UV adhesive prepared in Example 1 as the test object. Under illumination from an LED 365nm light source and a high-pressure mercury lamp, the energy of the adhesive is 1500 mJ / cm². 2 Then, relevant performance tests are conducted.

[0056] 2. Test Items

[0057] (1) Surface drying time: After exposure to light, test the surface tack of the UV adhesive by touch and start timing until there is no adhesive residue when the finger is removed. Record the time when the UV adhesive surface dries, which is the surface drying time.

[0058] (2) Final curing time: The time required for a UV adhesive to reach its maximum bonding strength from the start of light exposure is the final curing time.

[0059] 3. Test Results

[0060] Table 2. Performance test results of the UV adhesive in Example 1

[0061]

[0062]

[0063] As shown in Table 2, under the same conditions of other materials and operations in preparing the adhesive, the surface drying time and final curing time of the resulting adhesive increase with the increase of the imidazole accelerator content, and the surface drying time and final curing time are moderate. This indicates that the adhesive provided by the present invention achieves delayed curing of UV adhesive by introducing an imidazole accelerator. Moreover, when the mass of the imidazole accelerator accounts for 0.95% to 90% of the mass of the photoinitiator, the surface drying time and final curing time of the resulting UV adhesive increase regularly with the increase of the imidazole accelerator, i.e., the growth rate is stable; however, when the weight of the imidazole accelerator is 0.001 (the mass of the imidazole accelerator is less than 0.95% of the total mass of the photoinitiator), the surface drying time and final curing time of the resulting adhesive are too short to achieve the effect of delayed curing; when the weight of the imidazole accelerator is 10 (the mass of the imidazole accelerator is greater than 90% of the total mass of the photoinitiator), the resulting adhesive does not cure under UV light. This demonstrates that the adhesive provided by the present invention can accurately control the UV curing time of the adhesive by controlling the content of imidazole accelerators, thereby enabling more accurate control of the operating time during production and application, keeping the delayed curing time within a suitable range, facilitating process operation, and not affecting production efficiency.

[0064] Test Example 2

[0065] 1. Participants

[0066] This test example uses the UV adhesives prepared in Examples 1-8 and Comparative Examples 1-3 as test subjects. Under illumination from an LED 365nm light source and a high-pressure mercury lamp, the energy of these adhesives is 1500 mJ / cm². 2 Then, relevant performance tests are conducted.

[0067] 2. Test Items

[0068] (1) Surface drying time: After exposure to light, test the surface tack of the UV adhesive by touch and start timing until there is no adhesive residue when the finger is removed. Record the time when the UV adhesive surface dries, which is the surface drying time.

[0069] (2) Final curing time: The time required for a UV adhesive to reach its maximum bonding strength from the start of light exposure is the final curing time.

[0070] (3) Shear strength: The test was conducted in accordance with the contents specified in the national standard GB / T 6328-2021, and the adhesive material was 3003Al;

[0071] 3. Test Results

[0072] Table 3. Performance test results of UV adhesives in Examples 1-8 and Comparative Examples 1-3

[0073]

[0074]

[0075] The performance test results of the adhesives provided by Examples 1-8 and Comparative Examples 1-3 are shown in Table 3. Comparing the performance test results of Example 1 with those of Comparative Examples 1-3, compared to Examples 1-8, Comparative Example 1 did not add imidazole accelerators to the raw materials used to prepare the adhesive. The resulting adhesive had a surface drying time of 10s and a final curing time of 30s, which were too short to achieve the effect of delayed curing. Comparative Examples 2-3 used bisphenol A epoxy resin and epoxidized olefin epoxy resin as the main resins, respectively. The adhesive obtained in Comparative Example 2 had a slow curing time and low shear strength. The adhesive obtained in Comparative Example 3 could not be cured. This demonstrates that the present invention rationally sets the adhesive formulation, and by introducing imidazole accelerators, it delays the UV curing rate of cationic photoinitiators. The combination of the two enables the resin to continue curing relatively slowly even in the absence of light after initial curing under light irradiation, thereby extending the curing time. This facilitates the application of the adhesive provided by the present invention to opaque materials, making the process easier.

[0076] The performance test results of Examples 1 and 2-3 were compared. Table 3 shows that, under the same conditions of other materials and operations in preparing the adhesive, the imidazole accelerators used in Examples 2 and 3 were cyanoethyl imidazole and triisocyanate imidazole, respectively. The test results indicate that the surface drying time and final curing time of the resulting UV adhesive increase with increasing imidazole accelerator content, but the increase is small, making it difficult to accurately control the amount of imidazole accelerator added to achieve delayed curing of the adhesive at different curing times. Compared to Examples 2 and 3, the imidazole accelerator used in Example 1 was alkylimidazole (2E4MZ), which has good stability. The surface drying time and final curing time of the resulting adhesive increase steadily and regularly with increasing imidazole accelerator content. This indicates that the formulation of the adhesive provided in Example 1 uses alkylimidazole as an imidazole accelerator, and its combination with a cationic photoinitiator can effectively control the UV curing time of the adhesive, achieving regular control of the UV curing time by controlling the content of the imidazole accelerator.

[0077] The performance test results of Examples 1 and 4-5 were compared. Table 3 shows that, under the same conditions of other materials and operations in preparing the adhesive, the main resin used in Example 4 was bis((3,4-epoxycyclohexyl)methyl)adipate, resulting in a UV adhesive with a slow curing speed, and a significant increase in surface drying time and final curing time as the amount of imidazole accelerator increased. In Example 5, the main resin was vinylcyclohexene diester, resulting in a UV adhesive with a fast curing speed, and a smaller increase in surface drying time and final curing time as the amount of imidazole accelerator increased, making it difficult to accurately control the curing time of the adhesive by controlling the amount of imidazole accelerator. This indicates that the adhesive formulation provided in Example 1 uses a specific alicyclic epoxy resin, which has good compatibility with the photoinitiator provided by this invention, and can further delay the UV curing rate of the cationic photoinitiator.

[0078] The performance test results of Examples 1 and Examples 6-8 were compared. Table 3 shows that, under the same conditions of other materials and operations for preparing the adhesive, the raw materials used in Examples 6-8 did not include oxetane monomers or vinyl ether monomers, respectively. Therefore, the adhesive strength of the resulting adhesives was lower than that of the adhesive provided in Example 1. This indicates that, in this invention, by using the specific oxetane monomers and vinyl ether monomers described above, and by rationally setting the type and content of the oxetane monomer, the viscosity of the adhesive can be made moderate, promoting the full occurrence of the curing reaction and improving the adhesive strength and mechanical strength of the cured product. Simultaneously, it can delay the curing process to a certain extent, which is beneficial for effectively controlling the delayed curing time.

[0079] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention, but such modifications or substitutions are all within the scope of protection of the present invention.

Claims

1. A UV adhesive with controllable curing time, characterized in that, The raw materials include the following parts by weight: 50-100 parts of alicyclic epoxy resin and 0.11-4 parts of photoinitiator; The photoinitiator comprises a first component and a second component, wherein the first component is a cationic photoinitiator and the second component is an imidazole accelerator; the mass ratio of the imidazole accelerator to the cationic photoinitiator is 0.01 to 1:

1.

2. The UV adhesive with controllable curing time as described in claim 1, characterized in that, The imidazole accelerators include at least one of alkyl imidazole, cyanoethyl imidazole, cyanoethyl imidazole salt, and triisocyanate imidazole.

3. The UV adhesive with controllable curing time as described in claim 2, characterized in that, The imidazole accelerator is an alkyl imidazole.

4. The UV adhesive with controllable curing time as described in claim 3, characterized in that, The cationic photoinitiator includes one or more of iodonium salts and thionium salts; The mass ratio of the imidazole promoter to the cationic photoinitiator is 0.01 to 0.1:

1.

5. The UV adhesive with controllable curing time as described in claim 4, characterized in that, The cationic photoinitiator is triarylhexafluoroantimony thionium salt, and the imidazole accelerator is 2-ethyl-4-methylimidazolium.

6. The UV adhesive with controllable curing time as described in claim 4, characterized in that, The alicyclic epoxy resin is at least one of 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexylmethyl ester, poly[(2-epoxyethylene)-1,2-cyclohexanediol]2-ethyl-2-(hydroxymethyl)-1,3-propanediol ether, tetrahydroindene diepoxide, 1,2-epoxy-4-vinylcyclohexane, 3,4-epoxycyclohexylmethyl methacrylate, 3,4-epoxycyclohexyl methacrylate, and vinylcyclohexene dioxide.

7. The UV adhesive with controllable curing time as described in claim 1, characterized in that, The raw materials for the UV adhesive with controllable curing time also include active monomers, including oxetane monomers and / or vinyl ether monomers.

8. The UV adhesive with controllable curing time as described in claim 7, characterized in that, The oxetane monomer is at least one of 3-ethyl-3-hydroxymethyloxetane, 3-ethyl-3-[(2-ethylhexyloxy)methyl]epoxybutane, 3,3'-(oxybismethylene)bis(3-ethyl)oxetane, and 1,4-bis[(3-ethyl-3-oxetane-butylmethoxy)methyl]benzene.

9. The UV adhesive with controllable curing time according to claim 8, characterized in that, The amount of oxetane monomer to be fed is determined according to the ratio of 0 to 50: 50 to 100.

10. A method for preparing a UV adhesive with controllable curing time as described in any one of claims 1 to 9, characterized in that, The process includes the following steps: mixing the alicyclic epoxy resin, the cationic photoinitiator, the imidazole accelerator, and the active monomer, stirring until homogeneous, and then degassing under vacuum to obtain the UV adhesive with controllable curing time.

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