A dual-structure cushioning tape and its preparation method

Abstract

This invention discloses a dual-structure cushioning tape, comprising a tape body, which includes a silicone gel layer, a copper foil, an acrylic cushioning foam layer, and a self-adhesive layer. The bottom end of the silicone gel layer is bonded to the top end of the copper foil, the bottom end of the copper foil is bonded to the top end of the acrylic cushioning foam layer, and the bottom end of the acrylic cushioning foam layer is bonded to the self-adhesive layer. The silicone gel layer of the copper foil base of this invention has excellent high-temperature stability, and is not prone to aging, softening, delamination, or deformation under high-temperature environments, making it suitable for complex working environments with alternating high and low temperatures. At the same time, the silicone gel material itself has excellent air permeability and venting characteristics, allowing air to be quickly expelled from the bonding interface during tape application, effectively preventing air bubbles and hollow areas after bonding, ensuring flatness and long-term stability, eliminating bulging and delamination caused by air accumulation under high-temperature conditions, and extending the tape's service life.

Description

Technical Field

[0001] This invention belongs to the field of polymer composite materials technology, specifically relating to a dual-structure cushioning tape and its preparation method. Background Technology

[0002] In industrial production and daily maintenance, cushioning tape is a key material for protecting equipment, filling gaps, and reducing vibration. Electronic insulation industrial cushioning tape, as an industrial-grade product, uses PE acrylic foam as its backing material and achieves strong adhesion through a double-sided self-adhesive design. It also possesses properties such as high temperature resistance, water resistance, and acid and alkali resistance, covering the needs of various scenarios including electronics, machinery, and construction, becoming an upgraded solution to replace traditional tapes.

[0003] In the prior art, as shown in patent CN 223547945 U, a support and buffer tape for OLED screens is disclosed. Its structure typically includes a carrier layer, a buffer silicone gel layer, a copper foil layer, and an adhesive layer. Although this type of structure has certain buffering and heat dissipation capabilities, it still has significant drawbacks in practical applications.

[0004] 1. Poor air release: During the bonding process, traditional acrylic foam or silicone gel has difficulty in quickly expelling air from the interface, which easily leads to air bubbles and hollow areas, affecting the flatness of the bonding.

[0005] 2. Insufficient temperature resistance: Under high-temperature conditions (such as in vehicle environments), ordinary adhesive layers are prone to aging, softening, and even delamination, leading to bulging or delamination.

[0006] 3. Poor adaptability to curved surfaces: The rigidity and elasticity of existing tapes are difficult to balance, and stress concentration at the edges is likely to occur when they are applied to curved surfaces, resulting in lifting or peeling.

[0007] In view of this, the present invention aims to provide a dual-structure cushioning tape that solves the problems of poor air venting, poor high-temperature stability and poor adhesion to curved surfaces in the prior art through a unique layered design and modified foam formula. Summary of the Invention

[0008] The purpose of this invention is to provide a dual-structure cushioning tape and its preparation method to solve the problems mentioned in the background art.

[0009] To achieve the above objectives, the present invention provides the following technical solution: a dual-structure cushioning tape, comprising a tape body 1, wherein the tape body 1 comprises a silicone gel layer 3, a copper foil 4, an acrylic cushioning foam layer 5, and a self-adhesive layer 6 stacked sequentially.

[0010] The silicone gel layer 3 is a breathable addition-type silicone gel coating with through-pores, used to adhere to the workpiece and quickly expel air from the bonding interface; the copper foil 4 is sandwiched between the silicone gel layer 3 and the acrylic buffer foam layer 5 as a thermally conductive and high-temperature resistant support layer; the acrylic buffer foam layer 5 is an elastic buffer intermediate layer, forming an elastic gradient structure with the two side layers, which is suitable for curved surface buffering and shock absorption.

[0011] The acrylic cushioning foam layer 5 is made of the following components: by weight, 10 to 40 parts of solid cushioning particles and 30 to 90 parts of liquid acrylic matrix adhesive;

[0012] The copper foil 4 has a tensile strength of 200-250 MPa, which retains the high bonding strength of acrylic adhesive to the metal substrate and constructs a uniform microporous elastic structure, achieving a perfect coexistence of "strong adhesion" and "high buffering".

[0013] Preferably, in the acrylic cushioning foam layer 5, solid cushioning particles account for 15% to 25% of the total mass of the foam layer.

[0014] Preferably, the solid buffer particles account for 18% to 22% of the total mass of the acrylic buffer foam layer 5. Within this range, the buffer particles, such as TPU microspheres, achieve the best dispersion state in the liquid acrylic matrix, which not only constructs a uniform microporous elastic network for shock absorption, but also retains enough colloidal continuous phase for bonding.

[0015] Preferably, the solid buffer particles are one or more of thermoplastic polyurethane microspheres, expandable microspheres, or elastic porous polymer microspheres.

[0016] Preferably, the thermoplastic polyurethane microspheres are solid or foamed with a particle size of 50–300 μm; the expandable microspheres are low-boiling-point alkanes encapsulated in a thermoplastic polymer shell, with an unexpanded particle size of 10–20 μm and an expanded particle size of 10–50 μm; when heated, they expand in volume, which can further increase the bulkiness and compression resilience of the adhesive layer, giving the tape excellent fatigue resistance.

[0017] Preferably, the liquid acrylic matrix adhesive has a storage modulus (80-150 kPa) and viscosity (9000-16000 cps) of one of LOCTITE AA 3295, LOCTITE HHD 8600, or LOCTITE AA HF 8600, which has higher heat resistance, aging resistance, and wetting and penetration ability on metal substrates such as copper foil and stainless steel, thus fundamentally ensuring the stability of long-term use.

[0018] Preferably, the silicone gel layer 3 is a breathable addition-type silicone gel coating with a thickness of 20-50 μm and a through-pore structure. The microporous structure allows air molecules to escape through the adhesive layer at the moment of bonding, and has a wider temperature resistance range (-40℃~180℃). It will not soften or flow in high-temperature environments (such as car engine compartments or electronic devices that generate heat), effectively preventing bulging and adhesive overflow failure caused by thermal expansion.

[0019] Preferably, the surface of the tape body 1 is provided with several easy-tear grooves 2, which can be used to cleanly and neatly tear the tape without the need for scissors, and the tear edges are neat.

[0020] A method for preparing a dual-structure cushioning tape includes the following steps:

[0021] S1. Copper foil pretreatment: Select copper foil with a tensile strength of 200-250MPa and perform dust removal, degreasing, and plasma activation treatment on both sides; copper foil in this strength range has good flexibility and can be uniformly bonded to curved components.

[0022] S2. Silicone gel coating: Modified silicone gel is uniformly coated on one side of the copper foil, and the coating thickness is controlled to be 20-50μm. After pre-curing at room temperature, it is dried and shaped at a constant temperature. The maximum drying temperature is controlled at 150-160℃, and the coating line speed is controlled at 2-3m / min.

[0023] S3. Preparation of buffer adhesive: Slowly add 10-40 parts by weight of solid buffer particles to 30-90 parts by weight of liquid acrylic matrix adhesive system, and stir with a high-speed disperser for 30-60 minutes, with the stirring speed controlled at 800-1200 r / min;

[0024] S4. Vacuum degassing: After stirring, let stand for 10-20 minutes for vacuum degassing;

[0025] S5. Foam layer coating and curing: The degassed modified acrylic adhesive is evenly coated on the other side of the copper foil and cured in sections at a constant temperature. The maximum temperature is controlled at 120-130℃ and the coating line speed is controlled at 2-3m / min, so that the buffer particles and acrylic colloid cross-link and form.

[0026] S6. Self-adhesive coating: A self-adhesive layer is uniformly coated on the surface of the cured acrylic cushioning foam layer, and then cured and set at a low temperature to obtain a double-structure cushioning tape.

[0027] The technical effects and advantages of this invention are as follows:

[0028] 1. The silicone gel layer of the copper foil base of the tape has excellent high temperature resistance and stability. It is not prone to aging, softening, delamination and deformation in high temperature environments, making it suitable for complex working environments with alternating high and low temperatures. At the same time, the silicone gel material itself has excellent air permeability and air exhaust characteristics, which can quickly expel air from the bonding interface during the tape bonding process, effectively avoiding the problems of air bubbles and hollows after bonding, ensuring the flatness of the bonding and the stability of long-term use, and eliminating bulging and delamination failures caused by air accumulation under high temperature conditions.

[0029] 2. The modified acrylic cushioning foam layer has excellent compatibility and adhesion to metal substrates, and can be tightly bonded to various metal components and metal panels. It has high bonding strength, is not easy to fall off, and has excellent fixation stability. At the same time, the uniformly filled cushioning particles inside form an elastic porous cushioning structure with excellent impact absorption capacity. It effectively absorbs and disperses the stress generated by external extrusion, vibration and impact, and forms a good cushioning and protection effect for the bonded components, reducing the risk of device damage and structural loosening caused by external impact.

[0030] 3. This invention effectively balances the rigidity and elasticity of the tape by precisely matching and optimizing the ratio of buffer particles with the strength of copper foil. In the application scenarios of curved surfaces and arc-shaped components, the tape adheres evenly with the deformation of the curved surface, and the stress distribution within the adhesive layer is uniform, without the phenomenon of edge stress concentration. This fundamentally solves the problems of easy lifting, edge detachment, and loose adhesion of traditional buffer tapes when applying to curved surfaces, and greatly improves the adaptability to curved surfaces and the adhesion durability.

[0031] 4. Through optimized formulation, performance can be precisely controlled. Based on the impact protection, bonding conditions, and temperature environment requirements of different usage scenarios, corresponding parameter combinations are matched to balance multiple properties such as temperature resistance and venting, high-strength bonding, buffering and energy absorption, and resistance to curved surface deformation. It is suitable for bonding and protection scenarios in multiple fields such as precision electronics, new energy devices, curved hardware components, and automotive equipment, and has strong practicality and market applicability. Attached Figure Description

[0032] Figure 1 This is a perspective view of the present invention;

[0033] Figure 2 This is a side view of the present invention.

[0034] In the diagram: 1. Tape body; 2. Tear groove; 3. Silicone gel layer; 4. Copper foil; 5. Acrylic cushioning foam layer; 6. Self-adhesive layer. Detailed Implementation

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] Example 1: Basic Preparation Process and Material Selection

[0037] This embodiment demonstrates the basic structure and general preparation method of the dual-structure buffer tape of the present invention.

[0038] 1. Material Selection: Flexible copper foil with a tensile strength of 200-250 MPa is selected as the substrate. LOCTITE AA 3295 (two-component, toughened, medium viscosity, elastic after curing) is selected as the liquid acrylic matrix adhesive; thermoplastic polyurethane (TPU) microspheres with a particle size of 50-300 μm are selected as solid buffer particles. Addition-type silicone gel is selected as the raw material for the silicone gel layer.

[0039] 2. Pretreatment: Dust removal, degreasing and plasma activation treatment are performed on both sides of the copper foil to improve surface activity.

[0040] 3. Silicone gel coating: Silicone gel is uniformly coated on one side of the copper foil, with a thickness of 20-50μm. After pre-curing at room temperature, it is dried at a constant temperature for shaping. The maximum drying temperature is controlled at 150-160℃, and the coating line speed is controlled at 2-3 m / min.

[0041] 4. Preparation of acrylic buffer foam layer: Add solid buffer particles into liquid acrylic matrix glue according to the set ratio, stir with a high-speed disperser at 800-1200r / min for 30-60min, and then let stand for vacuum degassing for 10-20min.

[0042] 5. Lamination and Curing: The degassed adhesive is applied to the other side of the copper foil and cured in sections at a constant temperature to form an acrylic cushioning foam layer; finally, a self-adhesive layer is applied to the surface of the foam layer, cured and shaped at a low temperature, and easy-tear grooves are die-cut; during the curing process, the maximum temperature is controlled at 120-130℃, and the coating line speed is controlled at 2-3 m / min, so that the cushioning particles and acrylic colloid are fully cross-linked and formed.

[0043] It has been found that when the coating line speed is controlled at 2-3 m / min, combined with the aforementioned specific temperature range (120-160℃), the uniformity of the crosslinking density of the adhesive layer can be significantly improved. If the line speed is too high, air bubbles are easily generated inside the adhesive layer; if the line speed is too slow, production efficiency is low and it may lead to excessive shrinkage of the adhesive layer. The parameter combination of the present invention achieves the optimal balance between product quality and production efficiency.

[0044] Example 2: Performance verification of low particle ratio (comparative example)

[0045] To verify the effect of particle ratio on performance, this embodiment sets the mass ratio of solid buffer particles to 5%-15%, and the remaining processes are the same as in Embodiment 1.

[0046] Results Analysis: The acrylic colloid content in this formulation is too high, resulting in a dense and rigid foam film with insufficient internal buffering pores. Tests show that the tape has good adhesive strength, but weak elastic deformation capacity, low impact energy absorption rate (<60%), and poor cushioning and shock absorption. When used with conventional low-strength copper foil, stress concentration easily occurs on curved surfaces due to the excessive rigidity of the adhesive film, leading to localized delamination even with minor impacts. This formulation is only suitable for static bonding scenarios on flat surfaces without impact.

[0047] Example 3: Verification of medium particle ratio performance (preferred scheme of the present invention)

[0048] In this embodiment, the mass ratio of solid buffer particles is set to 15%-25%, and the remaining processes are the same as in Embodiment 1.

[0049] Results Analysis: The particles are uniformly dispersed in the colloid, and after curing, the adhesive film forms a uniform microporous elastic buffer structure. At this formulation, the rigidity and elasticity of the tape are balanced, retaining excellent metal adhesion performance while also possessing good impact absorption capabilities. When paired with copper foil with a tensile strength of 200-250 MPa, the flexibility of the copper foil can adapt to curved surface deformation, and the elasticity of the foam counteracts the internal stress of the bonding, significantly improving the anti-lifting performance.

[0050] Example 4: Performance Verification of High Particle Ratio (Comparative Example)

[0051] To verify the upper limit of particle size, this embodiment sets the mass ratio of solid buffer particles to 25%-35%, and the remaining processes are the same as in Embodiment 1.

[0052] Results analysis: Excessive particle filler content resulted in insufficient acrylic colloidal matrix ratio, poor interparticle bonding, and excessively high porosity and loose structure in the cured foam film. Although the cushioning and rebound effect was excellent, the adhesive adhesion was significantly reduced, and the film was prone to powdering and delamination, failing to meet long-term fixation requirements.

[0053] Example 5: Optimal Formulation and Performance Testing (Optimal Implementation Scheme of the Invention)

[0054] This embodiment represents the optimal implementation parameters of the present invention. A flexible copper foil with a tensile strength of 230 MPa is selected, and the mass ratio of buffer particles (TPU microspheres) is set to 20% (i.e., 80 parts of liquid acrylic matrix adhesive).

[0055] Example 6: Applicability Verification of Different Buffer Particles

[0056] This embodiment verifies the effects of different types of solid buffer particles, with the optimal ratio (18%-22%) used for all. The remaining processes are the same as in Embodiment 1.

[0057] 1. Option A (Thermoplastic polyurethane microspheres): Solid or foamed, highly resilient and wear-resistant, with a particle size of 50-300μm, suitable for cushioning in conventional electronic devices.

[0058] 2. Option B (Expandable Microspheres): Low-boiling-point alkanes are encapsulated in a thermoplastic polymer shell. After heating and expansion, they form closed-cell elastic hollow spheres with an unexpanded particle size of 10-20 μm and an expanded particle size of 10-50 μm. This option is suitable for structures that require secondary hot pressing.

[0059] 3. Option C (Elastic Porous Polymer Microspheres): Possesses high deformation recovery capability and is suitable for ultra-high compression rebound scenarios.

[0060] All three types of particles can achieve the purpose of this invention, among which Scheme A has the best overall cost and performance.

[0061] Practical testing has verified that the tape of this invention exhibits excellent adhesion durability and weather resistance on both sides. After aging for 240 hours in a harsh environment of 85℃ and 85%RH, the adhesiveness of both sides of the tape showed almost no decrease: the silicone gel side maintained an adhesiveness of 3000-4000 g / inch, and the acrylic foam side maintained an adhesiveness of around 3000 g / inch. This indicates that the present invention not only solves the problem of high-temperature debonding but also maintains extremely high performance stability in humid and hot environments, far exceeding the performance indicators of traditional cushioning tapes.

[0062] The applicant further declares that while the above embodiments illustrate the implementation method and apparatus structure of the present invention, the present invention is not limited to the above-described embodiments, meaning that the present invention must rely on the above methods and structures to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions for the selected implementation methods, additions to steps, and selections of specific methods all fall within the protection and disclosure scope of the present invention.

[0063] This invention is not limited to the above-described embodiments. All methods that employ similar structures and approaches to achieve the objectives of this invention are within the scope of protection of this invention.

Claims

1. A dual-structure cushioning tape, comprising a tape body (1), characterized in that: The tape body (1) includes a silicone gel layer (3), a copper foil (4), an acrylic cushioning foam layer (5), and a self-adhesive layer (6) stacked in sequence. The silicone gel layer (3) is a breathable addition-type silicone gel coating with through-hole micropores, used to adhere to the workpiece and quickly expel air from the bonding interface; the copper foil (4) is sandwiched between the silicone gel layer (3) and the acrylic buffer foam layer (5) as a thermally conductive and high-temperature resistant support layer; the acrylic buffer foam layer (5) is an elastic buffer intermediate layer, forming an elastic gradient structure with the two side layers, which is suitable for curved surface buffering and shock absorption. The acrylic cushioning foam layer (5) is made of the following components: by weight, 10 to 40 parts of solid cushioning particles and 30 to 90 parts of liquid acrylic matrix adhesive; The tensile strength of the copper foil (4) is 200-250 MPa.

2. The dual-structure cushioning tape according to claim 1, characterized in that: In the acrylic cushioning foam layer (5), solid cushioning particles account for 15% to 25% of the total mass of the foam layer.

3. The dual-structure cushioning tape according to claim 2, characterized in that: The solid buffer particles account for 18% to 22% of the total mass of the acrylic buffer foam layer (5).

4. The dual-structure cushioning tape according to claim 1, characterized in that: The solid buffer particles are one or more of thermoplastic polyurethane microspheres, expandable microspheres, or elastic porous polymer microspheres.

5. The dual-structure cushioning tape according to claim 4, characterized in that: The thermoplastic polyurethane microspheres are solid or foamed with a particle size of 50–300 μm; the expandable microspheres are low-boiling-point alkanes encapsulated in a thermoplastic polymer shell, with an unexpanded particle size of 10–20 μm and an expanded particle size of 10–50 μm.

6. The dual-structure cushioning tape according to claim 1, characterized in that: The storage modulus (80-150 kPa) and viscosity (9000-16000 cps) of the liquid acrylic matrix adhesive are one of LOCTITE AA 3295, LOCTITE HHD 8600 or LOCTITE AA HF 8600.

7. The dual-structure cushioning tape according to claim 1, characterized in that: The silica gel layer (3) is a breathable addition-type silica gel coating with a thickness of 20-50 μm and a through-hole microporous structure.

8. The dual-structure cushioning tape according to claim 1, characterized in that: The surface of the tape body (1) is provided with several easy-tear grooves (2).

9. A method for preparing a dual-structure cushioning tape according to any one of claims 1 to 8, characterized in that, Includes the following steps: S1. Copper foil pretreatment: Select copper foil with a tensile strength of 200-250MPa and perform dust removal, degreasing, and plasma activation treatment on both sides; S2. Silicone gel coating: Modified silicone gel is uniformly coated on one side of the copper foil, and the coating thickness is controlled to be 20-50μm. After pre-curing at room temperature, it is dried and shaped at a constant temperature. The maximum drying temperature is controlled at 150-160℃, and the coating line speed is controlled at 2-3m / min. S3. Preparation of buffer adhesive: Slowly add 10-40 parts by weight of solid buffer particles to 30-90 parts by weight of liquid acrylic matrix adhesive system, and stir with a high-speed disperser for 30-60 minutes, with the stirring speed controlled at 800-1200 r / min; S4. Vacuum degassing: After stirring, let stand for 10-20 minutes for vacuum degassing; S5. Foam layer coating and curing: The degassed modified acrylic adhesive is evenly coated on the other side of the copper foil and cured in sections at a constant temperature. The maximum temperature is controlled at 120-130℃ and the coating line speed is controlled at 2-3m / min, so that the buffer particles and acrylic colloid cross-link and form. S6. Self-adhesive layer coating: A self-adhesive layer is uniformly coated on the surface of the cured acrylic cushioning foam layer, and then cured and shaped at low temperature to obtain a double-structure cushioning tape.

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