Thermosetting acrylic foaming foam double-sided adhesive tape and preparation method thereof

Abstract

The invention provides a thermosetting acrylic foaming cotton double-sided adhesive tape, which comprises a thermosetting foaming cotton adhesive layer and a release layer superposed with the thermosetting foaming cotton adhesive layer, and the thermosetting foaming cotton adhesive layer comprises the following components by weight: 50-100 parts of acrylic glue; 5 to 10 parts of tackifying resin; 10 to 20 parts of a solvent; 0.5 to 2.5 parts of thermoplastic spheres; and 0.5-2 parts of a curing agent. The foaming foam double-sided tape has good compressibility and impact resistance, and can bear suddenly increased impact force. The invention also provides a preparation method of the thermosetting acrylic foaming foam double-sided adhesive tape.

Description

Technical Field

[0001] The invention belongs to the technical field of adhesives, and in particular relates to a thermosetting acrylic foam cotton double-sided tape and a preparation method thereof. Background Art

[0002] With the progress and development of society, people are increasingly dependent on electronic devices in their daily lives, especially mobile phones and computers. The current trend in smartphone design is to use almost edgeless displays, and the touch screen needs to occupy as much space as possible, so the applicable bonding area for lenses and touch panels is reduced. Although the available bonding area is getting smaller and smaller, the requirements for the comprehensive performance of the tape remain unchanged, especially the requirements for the impact resistance of the tape. It must be ensured that the tape can withstand the sudden increase in impact force in the event that the smartphone may accidentally fall.

[0003] The compression and activation pressure of the tapes on the market are relatively high, but the impact resistance is average, and too much pressure holding pressure will damage the existing LED screen. Existing acrylic foam tapes are all produced by adding glass microspheres to light-cured acrylic acid. The 25% CFD of the products is >600KPa. It has a large compression rebound resistance, but poor compressibility and impact resistance. Summary of the invention

[0004] The purpose of the present invention is to provide a thermosetting acrylic foam double-sided tape to address the deficiencies of the prior art. The foam double-sided tape has good compressibility and impact resistance and can withstand a sudden increase in impact force. The present invention also provides a preparation method of the acrylic foam double-sided tape.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] The present invention discloses a thermosetting acrylic foam double-sided tape, comprising a thermosetting foam adhesive layer and a release layer superimposed thereon, wherein the thermosetting foam adhesive layer comprises the following components in parts by weight:

[0007]

[0008] The tackifying resin described in the present invention is one or more of rosin resin, β-terpene resin and alkylphenol-formaldehyde resin.

[0009] The solvent is one of ethyl acetate, IPA and toluene.

[0010] The thermoplastic sphere described in the present invention refers to a sphere whose outer shell is a thermoplastic resin or polymer, and the thermoplastic sphere is one or more of solid microspheres, hollow microspheres, double-layer microspheres, and porous microspheres.

[0011] The particle size of the thermoplastic sphere is 5 to 20 μm.

[0012] The curing agent is one of an isocyanate curing agent or an epoxy curing agent.

[0013] The isocyanate curing agent is selected from one of TDI, HDI and PDI; the epoxy curing agent is selected from one of polyamines, acid anhydrides and polythiol.

[0014] In the present invention, the thickness of the thermosetting foam adhesive layer is 0.05-0.4 mm.

[0015] The release layer is one of a PET release film, a PE release film and a release paper; and the thickness of the release layer is 25 to 75 μm.

[0016] The present invention also provides a method for preparing the thermosetting acrylic foam double-sided tape, comprising the following steps:

[0017] S1: Dissolve the solvent, tackifying resin and thermoplastic spheres in acrylic glue in proportion, stir for 30-50 minutes, then add curing agent, stir for another 15-30 minutes and apply on the release layer, set the oven temperature to make the thermoplastic spheres expand due to heat, and when the product thickness increases by 1.3-1.5 times, a thermosetting foam product is obtained after it comes out of the oven;

[0018] S2 rolls or layers the thermosetting foam product to obtain a thermosetting acrylic foam double-sided tape.

[0019] The oven temperature was set at 60-70-80-100-120-120-120-80°C.

[0020] When the tape is used, after tearing off the release layer, use the thermosetting foam adhesive layer for bonding.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] (1) The foamed cotton double-sided tape of the present invention has good impact resistance and can withstand a sudden increase in impact force.

[0023] (2) The thermosetting foam rubber layer of the present invention uses thermoplastic spheres, which expand when heated in an oven and increase in volume uniformly. The spheres have good compressibility and cushioning force, and can withstand a pressure of 100 MPa after compression. DETAILED DESCRIPTION

[0024] The present invention will be further described below with reference to specific embodiments, but is not limited thereto.

[0025] In this specific embodiment, a thermosetting acrylic foam double-sided tape includes a thermosetting foam adhesive and a release layer superimposed thereon, wherein the thermosetting foam adhesive includes the following components in parts by weight:

[0026] Acrylic glue 50-100 parts

[0027]

[0028] The thermoplastic sphere is one of solid microspheres, hollow microspheres, double-layer microspheres and porous microspheres, and has a particle size of 5 to 20 μm.

[0029] The preparation method of the thermosetting acrylic foam double-sided tape in this specific implementation comprises the following steps:

[0030] S1: Dissolve the solvent, tackifying resin and thermoplastic spheres in acrylic glue in proportion, stir for 30-50 minutes, then add curing agent, stir for another 15-30 minutes and apply on the release layer, set the oven temperature to make the thermoplastic spheres expand due to heat, and when the product thickness increases by 1.3-1.5 times, a thermosetting foam product is obtained after it comes out of the oven;

[0031] S2 rolls or layers the thermosetting foam product to obtain a thermosetting acrylic foam double-sided tape.

[0032] In the specific embodiment, Examples 1-6 are used to prepare the thermosetting acrylic foam double-sided tape of the present invention, and Comparative Examples 1-2 are used to prepare the double-sided tape; wherein the formula of each component in the adhesive layer is shown in Table 1, and the formula composition is calculated by weight of the raw materials:

[0033] Table 1 Formula of thermosetting foam adhesive layer (unit: part)

[0034]

[0035]

[0036] The components of each embodiment and comparative example in Table 1 above were used to prepare finished tapes according to the above-mentioned method for preparing the thermosetting acrylic foam cotton double-sided tape.

[0037] Performance Testing

[0038] The double-sided tapes prepared in Examples 1-6 and Comparative Examples 1-2 were subjected to performance tests. The test results are shown in Table 2. The test items, test methods and standards are as follows:

[0039] The tensile strength and elongation at break were tested using a universal material testing machine, referring to GB / T30776-2014;

[0040] The steel plate peeling force test is carried out using a peeling force test machine, referring to GB / T 2792-2014;

[0041] Compression CFD reference ASTM D3574-17

[0042] The dynamic shear force of the steel plate is tested using a peel force tester, referring to GB / T33332-2016.

[0043] Table 2 Performance test results of embodiments and comparative examples

[0044]

[0045] As can be seen from the above table, the products prepared in Examples 1-6 of the present invention have excellent performance in all aspects. While maintaining the original performance, the 25% CFD compressive stress is smaller, the stress absorption effect is better, and it can better meet the applications of existing electronic product frame glue. Moreover, by combining different types of thermoplastic spheres, a better stress absorption effect can be achieved. Therefore, the selection of thermoplastic spheres and combinations is also particularly important. Comparative Example 1 uses light-curing acrylic glue and glass microspheres. Although the tensile strength, elongation at break and peel force of the product are not significantly reduced, the 25% CFD compressive stress increases, and the stress absorption effect is poor; Comparative Example 2 uses acrylic glue and glass microspheres, the 25% CFD compressive stress is larger, and the stress absorption effect is worse.

Claims

1. A thermosetting acrylic foam double-sided tape, comprising a thermosetting foam adhesive layer and a release layer superimposed thereon, characterized in that The thermosetting foam adhesive layer comprises the following components in parts by weight:

2. The thermosetting acrylic foam double-sided tape according to claim 1, characterized in that The thermoplastic sphere refers to a sphere whose outer shell is a thermoplastic resin or polymer, and the thermoplastic sphere is one or more of solid microspheres, hollow microspheres, double-layer microspheres, and porous microspheres.

3. The thermosetting acrylic foam double-sided tape according to claim 1, characterized in that The tackifying resin is one or more of rosin resin, beta-terpene resin and alkylphenol-formaldehyde resin.

4. The thermosetting acrylic foam double-sided tape according to claim 1, characterized in that The solvent is one of ethyl acetate, IPA and toluene.

5. The thermosetting acrylic foam double-sided tape according to claim 1, characterized in that The curing agent is one of an isocyanate curing agent or an epoxy curing agent.

6. The thermosetting acrylic foam double-sided tape according to claim 5, characterized in that The isocyanate curing agent is selected from one of TDI, HDI and PDI; the epoxy curing agent is selected from one of polyamines, acid anhydrides and polythiol.

7. The thermosetting acrylic foam double-sided tape according to claim 1, characterized in that The thickness of the thermosetting foam adhesive layer is 0.05-0.4 mm.

8. The thermosetting acrylic foam double-sided tape according to claim 1, characterized in that The release layer is one of a PET release film, a PE release film and a release paper; and the thickness of the release layer is 25 to 75 μm.

9. A method for preparing the thermosetting acrylic foam double-sided tape according to any one of claims 1 to 8, characterized in that The following steps are involved: S1: Dissolve the solvent, tackifying resin and thermoplastic spheres in acrylic glue in proportion, stir for 30-50 minutes, then add curing agent, stir for another 15-30 minutes and apply on the release layer, set the oven temperature to make the thermoplastic spheres expand due to heat, and when the product thickness increases by 1.3-1.5 times, a thermosetting foam product is obtained after it comes out of the oven; S2 rolls or layers the thermosetting foam product to obtain a thermosetting acrylic foam double-sided tape.

10. The method for preparing the thermosetting acrylic foam double-sided tape according to claim 9, characterized in that The oven temperature was set at 60-70-80-100-120-120-120-80°C.

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