Black anti-impact supporting adhesive tape as well as preparation method and application thereof

Abstract

The invention provides a black anti-impact supporting adhesive tape and a preparation method and application thereof. The black anti-impact supporting adhesive tape is of a single-layer structure. The raw material of the black anti-impact supporting adhesive tape comprises an organic silicon optical pressure-sensitive adhesive; the organic silicon optical pressure-sensitive adhesive is prepared from the following components in parts by weight: 40 to 55 parts of methyl MQ silicon resin, 0.5 to 3 parts of hydrogen-containing silicon resin, 15 to 32 parts of vinyl-terminated silicone oil, 0.5 to 3 parts of single-walled carbon nanotubes, 1 to 3 parts of an inhibitor, 15 to 30 parts of a diluent and 0.9 to 1 part of a catalyst. The black anti-impact supporting adhesive tape has excellent anti-impact performance, supporting performance, bonding performance, bonding reliability and low light transmittance, does not need to adopt a multi-layer composite structure of a PI supporting film, a PSA pressure-sensitive adhesive and black buffer foam, and is simple in structure and low in cost.

Description

Technical Field

[0001] This invention belongs to the field of optical materials technology, specifically relating to a black impact-resistant support tape, its preparation method, and its application. Background Technology

[0002] With the development of technology, mobile phone displays are now primarily made of OLED and AMOLED screens, and this trend is gradually extending to other display fields such as watches, home appliances, tablets, and televisions. OLED is becoming the focus of the entire electronics industry. Compared to traditional LCD screens, OLED technology, which replaces liquid crystals for light emission, offers advantages such as higher contrast, faster color switching, thinner profile, narrower bezels, lower screen-to-body ratio, and lower power consumption; thus, it is gradually becoming the mainstream display panel.

[0003] During the production of OLED (AMOLED) module products, it is usually necessary to attach composite tape to the back of the OLED panel to form a heat dissipation film with thermally conductive copper foil or SUS; this provides the OLED screen with functions such as drop resistance, energy absorption, and light absorption to prevent light leakage.

[0004] Traditional OLED under-display composite tape consists of three layers: a PI support film, a PSA pressure-sensitive adhesive, and black cushioning foam. The PI support film provides support, addressing the issue of the soft and poorly supportive black foam. The PSA adhesive provides adhesion, bonding the black foam to the PI support film. The black foam also absorbs light and cushions the screen, preventing light leakage and damage from drops. However, in practical applications, the soft foam layer of traditional composite tape easily leads to localized damage to the screen during daily use, causing display defects. Furthermore, its impact resistance and energy absorption are generally poor. Additionally, the multi-layered structure of traditional composite tape makes integration complex. As product thinning, impact resistance, and reliability requirements increase, traditional OLED under-display composite tape can no longer meet the growing demands.

[0005] Therefore, developing a tape with a simple structure and excellent impact resistance, support properties, adhesive properties, adhesive reliability, and low light transmittance is an urgent problem to be solved in this field. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the present invention aims to provide a black impact-resistant support tape, its preparation method, and its applications. The black impact-resistant support tape possesses excellent impact resistance, support performance, adhesion performance, bonding reliability, and low light transmittance. It eliminates the need for a multi-layered composite structure consisting of a PI support film, PSA pressure-sensitive adhesive, and black cushioning foam, resulting in a simple structure and low cost.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides a black impact-resistant support tape, wherein the black impact-resistant support tape has a single-layer structure; the raw material of the black impact-resistant support tape includes an organosilicon optical pressure-sensitive adhesive; and the organosilicon optical pressure-sensitive adhesive comprises the following components by weight:

[0009] 40-55 parts of methyl MQ silicone resin

[0010] 0.5-3 parts of hydrogen-containing silicone resin;

[0011] 15-32 parts of vinyl-terminated silicone oil;

[0012] 0.5-3 parts of single-walled carbon nanotubes

[0013] Inhibitor 1-3 parts

[0014] 15-30 parts diluent;

[0015] Catalyst 0.9-1 part.

[0016] In this invention, the silicone pressure-sensitive adhesive is formulated with methyl MQ silicone resin, hydrogen-containing silicone resin, and vinyl-terminated silicone oil. This combination ensures good adhesion even at extremely thin thicknesses while maintaining low modulus and low loss characteristics. It maximizes the absorption rate of falling balls, far exceeding that of foam, effectively buffering surface forces and dispersing small point forces into surface forces, thus improving the tape's impact resistance. Furthermore, it gives the tape high tensile strength, high cohesive strength, excellent extrusion resistance, and good support. Further, the addition of single-walled carbon nanotubes ensures extremely low light transmittance, improving the display effect of OLED screens, while also providing conductivity. It possesses antistatic properties, protecting mobile phones and other electronic devices and reducing their malfunctions. Furthermore, it considers system compatibility and coating process feasibility, without affecting the adhesive's bonding performance and modulus. The use of a compound of methyl MQ silicone resin, hydrogen-containing silicone resin, vinyl-terminated silicone oil, and single-walled carbon nanotubes simplifies the tape structure. This allows the black impact-resistant support tape to simultaneously possess adhesive performance, bonding reliability, impact resistance, support performance, and low light transmittance in a single-layer structure, eliminating the need for a multi-layer composite structure of PI support film, PSA pressure-sensitive adhesive, and black cushioning foam. This simplifies the manufacturing process, reduces costs, and meets lightweight performance requirements.

[0017] In this invention, 40-55 parts of methyl MQ silicone resin are used, for example, 41 parts, 42 parts, 43 parts, 44 parts, 45 parts, 46 parts, 47 parts, 48 ​​parts, 49 parts, 50 parts, 51 parts, 52 parts, 53 parts, 54 parts, etc.

[0018] In this invention, the amount of hydrogen-containing silicone resin is 0.5-3 parts, for example, it can be 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, 1 part, 1.1 parts, 1.2 parts, 1.3 parts, 1.4 parts, 1.5 parts, 1.6 parts, 1.7 parts, 1.8 parts, 1.9 parts, 2 parts, 2.1 parts, 2.2 parts, 2.3 parts, 2.4 parts, 2.5 parts, 2.6 parts, 2.7 parts, 2.8 parts, 2.9 parts, etc.

[0019] In this invention, the vinyl-terminated silicone oil is 15-32 parts, for example, 16 parts, 17 parts, 18 parts, 19 parts, 20 parts, 21 parts, 22 parts, 23 parts, 24 parts, 25 parts, 26 parts, 27 parts, 28 parts, 29 parts, 30 parts, 31 parts, etc.

[0020] In this invention, the single-walled carbon nanotubes are 0.5-3 parts, for example, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, 1 part, 1.1 parts, 1.2 parts, 1.3 parts, 1.4 parts, 1.5 parts, 1.6 parts, 1.7 parts, 1.8 parts, 1.9 parts, 2 parts, 2.1 parts, 2.2 parts, 2.3 parts, 2.4 parts, 2.5 parts, 2.6 parts, 2.7 parts, 2.8 parts, 2.9 parts, etc.

[0021] In this invention, the inhibitor is 1-3 parts, for example, it can be 1 part, 1.1 parts, 1.2 parts, 1.3 parts, 1.4 parts, 1.5 parts, 1.6 parts, 1.7 parts, 1.8 parts, 1.9 parts, 2 parts, 2.1 parts, 2.2 parts, 2.3 parts, 2.4 parts, 2.5 parts, 2.6 parts, 2.7 parts, 2.8 parts, 2.9 parts, etc.

[0022] In this invention, the diluent is 15-30 parts, for example, 16 parts, 18 parts, 20 parts, 22 parts, 24 parts, 26 parts, 28 parts, etc.

[0023] In this invention, the catalyst is 0.9-1 parts, for example, it can be 0.92, 0.94, 0.96, 0.98 parts, etc.

[0024] Preferably, the M / Q ratio in the methyl MQ silicone resin is 0.6 to 0.8, for example, it can be 0.62, 0.64, 0.66, 0.68, 0.7, 0.72, 0.74, 0.76, 0.78, etc.

[0025] Preferably, the weight-average molecular weight of the methyl MQ silicone resin is 3000~10000 g / mol, for example, it can be 3500 g / mol, 4000 g / mol, 4500 g / mol, 5000 g / mol, 5500 g / mol, 6000 g / mol, 6500 g / mol, 7000 g / mol, 7500 g / mol, 8000 g / mol, 8500 g / mol, 9000 g / mol, 9500 g / mol, etc.

[0026] Preferably, the mass percentage of active hydrogen in the hydrogen-containing silicone resin is ≥0.95%, for example, it can be 0.96%, 0.98%, 1%, 1.02%, 1.04%, 1.06%, 1.08%, 1.1%, 1.12%, 1.15%, 1.18%, 1.2%, 1.22%, 1.25%, 1.28%, 1.3%, 1.32%, 1.35%, 1.38%, 1.4%, 1.42%, 1.45%, etc.

[0027] Preferably, the M / Q ratio in the hydrogen-containing silicone resin is 0.6 to 0.8, for example, it can be 0.62, 0.64, 0.66, 0.68, 0.7, 0.72, 0.74, 0.76, 0.78, etc.

[0028] Preferably, the weight-average molecular weight of the hydrogen-containing silicone resin is 1000~5000 g / mol, for example, it can be 1200 g / mol, 1500 g / mol, 1800 g / mol, 2000 g / mol, 2200 g / mol, 2500 g / mol, 2800 g / mol, 3000 g / mol, 3200 g / mol, 3500 g / mol, 3800 g / mol, 4000 g / mol, 4200 g / mol, 4500 g / mol, 4800 g / mol, etc.

[0029] Preferably, the terminal vinyl silicone oil has the structure shown in Formula I.

[0030] Formula I.

[0031] Where a is an integer ≥ 1, such as 2, 4, 8, 12, 16, 20, 30, 40, 60, 80, 100, 150, 200, 250, 300, etc.

[0032] In this invention, the viscosity (25°C) of the vinyl-terminated silicone oil is 50,000~200,000 mpa·s, for example, it can be 60,000 mpa·s, 80,000 mpa·s, 100,000 mpa·s, 120,000 mpa·s, 140,000 mpa·s, 160,000 mpa·s, 180,000 mpa·s, etc.

[0033] Preferably, the average particle size of the single-walled carbon nanotubes is 1~5nm, for example, it can be 1.5 nm, 2 nm, 2.5 nm, 3 nm, 3.5 nm, 4 nm, 4.5 nm, etc.

[0034] Preferably, the inhibitor comprises any one or a combination of at least two of alkynyl alcohols, vinyl cyclic compounds, polyvinyl silicone oils, and maleate esters.

[0035] In this invention, the alkynol compounds include 1-ethynyl-1-cyclohexanol.

[0036] Preferably, the diluent comprises any one or a combination of at least two of petroleum ether, white spirit, xylene, toluene, n-heptane, ethyl acetate, and cyclohexane.

[0037] Preferably, the catalyst comprises a platinum catalyst, which includes any one or a combination of at least two of chloroplatinic acid, Karstedt platinum catalyst, and Willing platinum catalyst.

[0038] In this invention, the Pt concentration of the catalyst is 20-200 ppm, for example, it can be 40 ppm, 60 ppm, 80 ppm, 100 ppm, 120 ppm, 140 ppm, 160 ppm, 180 ppm, etc.

[0039] Preferably, the thickness of the black impact-resistant support tape is 60~80μm, for example, it can be 62μm, 65μm, 68μm, 70μm, 72μm, 75μm, 78μm, etc.

[0040] In this invention, the viscosity of the silicone pressure-sensitive adhesive is 1000-20000 mpa•s (25°C), preferably 5000-15000 mpa•s; the glass transition temperature of the black impact-resistant support tape after curing is less than 40°C.

[0041] In a second aspect, the present invention provides a method for preparing a black impact-resistant support tape according to the first aspect, the method comprising: coating an organosilicon optical pressure-sensitive adhesive onto the surface of a substrate and curing it to obtain the black impact-resistant support tape.

[0042] In this invention, the preparation method of the organosilicon optical pressure-sensitive adhesive includes: mixing the components, stirring at 300-500 rpm for 50-70 min, and degassing at 0.1-0.3 MPa for 1-10 min to obtain the organosilicon pressure-sensitive adhesive.

[0043] In this invention, the coating includes, but is not limited to, scraping; the substrate can be a heavy release film, such as a fluorinated release film; the release force of the heavy release film is 15-25 gf / 25 mm; after curing, a light release film (such as a fluorinated release film) can be attached to the surface of the pressure-sensitive adhesive layer away from the heavy release film, and the release force of the light release film is 1-5 gf / 25 mm.

[0044] Preferably, the curing process includes: curing at 80~100℃ (e.g., 82℃, 85℃, 88℃, 90℃, 92℃, 95℃, 98℃, etc.) for 1~5 minutes (e.g., 2 minutes, 3 minutes, 4 minutes, etc.), then curing at 110~130℃ (e.g., 112℃, 115℃, 118℃, 120℃, 122℃, 125℃, 128℃, etc.) for 1~5 minutes (e.g., 2 minutes, 3 minutes, 4 minutes, etc.), and then curing at 130~150℃ (e.g., 132℃, 135℃, 138℃, 140℃, 142℃, 145℃, 148℃, etc.) for 1~5 minutes (e.g., 2 minutes, 3 minutes, 4 minutes, etc.).

[0045] Thirdly, the present invention provides an impact-resistant heat dissipation tape, the impact-resistant heat dissipation tape comprising sequentially stacked metal layers and the black impact-resistant support tape described in the first aspect.

[0046] Preferably, the metal layer includes a metal foil layer, such as copper foil, aluminum foil, etc.

[0047] Preferably, the impact-resistant heat dissipation tape further includes a release film, which is located on the surface of the black impact-resistant support tape.

[0048] Fourthly, the present invention provides an OLED display screen, the OLED display screen comprising the black impact-resistant support tape described in the first aspect or the impact-resistant heat dissipation tape described in the third aspect.

[0049] The numerical range described in this invention includes not only the point values ​​listed above, but also any point values ​​within the numerical ranges not listed above. Due to space limitations and for the sake of brevity, this invention will not exhaustively list all the specific point values ​​included in the range.

[0050] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0051] The black impact-resistant support tape provided by this invention is a compound of methyl MQ silicone resin, hydrogen-containing silicone resin, vinyl-terminated silicone oil, and single-walled carbon nanotubes. This simplifies the tape structure, enabling the black impact-resistant support tape to simultaneously possess adhesive properties, reliable adhesion, impact resistance, support properties, and low light transmittance in a single-layer structure. This simplifies the manufacturing process and reduces costs. Detailed Implementation

[0052] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0053] All materials used in this invention can be purchased commercially or prepared using conventional methods. Unless otherwise specified, the materials used in this invention are shown in Table 1.

[0054] Table 1

[0055]

[0056] Example 1

[0057] This embodiment provides a black impact-resistant support tape, which has a single-layer structure; the raw material of the black impact-resistant support tape is an organosilicon optical pressure-sensitive adhesive; the formulation of the organosilicon optical pressure-sensitive adhesive by weight is shown in Table 2.

[0058] This embodiment provides a method for preparing a black impact-resistant support tape, specifically including the following steps:

[0059] (1) Rubber preparation

[0060] The components of the silicone optical pressure-sensitive adhesive were stirred evenly in a dispersion pan at 400 rpm for 60 minutes. After stirring, the resulting adhesive solution was degassed under high pressure (0.15 MPa for 5 minutes) and then prepared for coating.

[0061] (2) Coating

[0062] The prepared adhesive solution in step (1) is applied to the heavy release film (fluorine release film) using a solvent-based coating equipment and a comma-shaped doctor blade. The thickness is calibrated to 70 μm by adjusting the equipment and the coating speed is 1 m / min. The pre-curing conditions are 90℃ / 2min, 120℃ / 2min, and 140℃ / 2min in sequence. Then, a light release film (fluorine release film) is applied and the tape is rolled up to obtain the black impact-resistant support tape.

[0063] Examples 2-9, Comparative Examples 1-5

[0064] Examples 2-9 and Comparative Examples 1-5 each provide a black impact-resistant support tape. The only difference between them and Example 1 is that the formulation of the silicone optical pressure-sensitive adhesive is different, as shown in Tables 2 and 3. The other structures and preparation methods are the same as those in Example 1.

[0065] Table 2

[0066]

[0067] Table 3

[0068]

[0069] Performance testing

[0070] (1) Modulus: The test was conducted using a rheometer. The test conditions were: frequency 1 Hz, heating rate 2℃ / min, and temperature range -60℃ to 60℃.

[0071] (2) Peeling force:

[0072] 1. Select a standard test steel plate with dimensions of 150mm x 50mm x 2mm and wipe the surface clean with alcohol.

[0073] 2. Cut the black impact support tape to a size of 150mm x 25mm, peel off the light release film, attach the sample to the steel plate with rollers, attach the traction belt, and roll it back and forth once with an electric pressure roller of 2kg at a speed of 10mm / s.

[0074] 3. Place the rolled sample in the test fixture, and then use a peel force tester to separate it at a rate of 300 mm / min. Test the peel force at 180° at 25±1℃, and record the average value of the peel interval.

[0075] (3) Light transmittance: The light transmittance and haze of transparent plastics shall be tested in accordance with the method in the national standard GB / T 2410-2008.

[0076] (4) Impact absorption rate of falling ball: Remove the light release film from the black impact support tape, place it on the test platform of the foam impact performance tester, and drop a 10g steel ball from a height of 75cm onto the black impact support tape to compare the impact absorption rate brought by air impact.

[0077] Formula for calculating the impact absorption rate of falling balls: K=(T1-T2) / T1×100%;

[0078] K: Impact absorption rate of falling ball;

[0079] T1: Impact force when dropped from a distance (N);

[0080] T2: Impact force (N) of hitting the black anti-impact support tape;

[0081] (5) Glass transition temperature Tg: Tested using a rheometer, according to the standard GB / T40396 2021.

[0082] (6) Elongation at break: The test shall be conducted in accordance with the method in the national standard GB / T 1701-2001 Determination of elongation at break of hard rubber.

[0083] (7) Room temperature holding power: The holding power of adhesive tapes shall be tested in accordance with the test method specified in GB / T 4851-2014; the specific steps are as follows:

[0084] 1. Select three steel plates for holding power testing, each measuring 50mm x 50mm x 2mm (length x width x thickness), and wipe the surface clean with alcohol;

[0085] 2. Cut the black impact support tape to a size of 25mm x 150mm. Remove the light release film, attach the PET, and then remove the heavy release film. Use a roller to attach the sample to the holding steel plate. Use a 2kg electric pressure roller to roll back and forth once at a speed of 10mm / s. Use a utility knife to cut off the excess adhesive part, leaving an adhesive area of ​​25mm x 25mm.

[0086] 3. Place the cut sample in the holding power test fixture, hang a 1kg weight underneath, then zero the timer and start timing, recording the time it takes for the tape to fall; test three samples at a time. (Take the minimum value among the three samples as the final judgment result).

[0087] If the room temperature holding power is greater than 24 hours, it is marked "OK"; if it is less than or equal to 24 hours, it is marked "NG".

[0088] The specific test results are shown in Table 4; where " / " indicates that there is no cross-linking agent and cross-linking curing is not possible, so the test cannot be performed.

[0089] Table 4

[0090]

[0091] As shown in Table 4, the black impact-resistant support tape provided by this invention is a composite of methyl MQ silicone resin, hydrogen-containing silicone resin, vinyl-terminated silicone oil, and single-walled carbon nanotubes, which simplifies the tape structure. This allows the black impact-resistant support tape to simultaneously possess adhesive performance, adhesive reliability, impact resistance, support performance, and low light transmittance in a single-layer structure, simplifying the manufacturing process and reducing costs. The black impact-resistant support tape has a modulus of 96~245KPa, a peel force of 13.5~24.8N / 25mm, a falling ball impact absorption rate of 39~50%, an elongation at break of 960~1600%, and a room temperature holding power of more than 24h.

[0092] As can be seen from the comparison between Example 1 and Comparative Example 2, the hydrogen-containing silicone resin content is too high, the modulus is high, and the resistance to falling ball impact is poor.

[0093] As can be seen from the comparison between Example 1 and Comparative Examples 3 and 4, the content of the methyl MQ silicone resin and the vinyl-terminated silicone oil is not within a specific range, resulting in poor resistance to falling ball impact and / or poor adhesion and short holding time.

[0094] As can be seen from the comparison between Example 1 and Comparative Example 5, replacing single-walled carbon nanotubes with black pigment not only increases light transmittance but also reduces peel strength.

[0095] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A black impact-resistant support tape, characterized in that, The black impact-resistant support tape has a single-layer structure; The raw material of the black impact-resistant support tape includes silicone optical pressure-sensitive adhesive; The silicone optical pressure-sensitive adhesive comprises the following components in parts by weight: 40-55 parts of methyl MQ silicone resin 0.5-3 parts of hydrogen-containing silicone resin 15-32 parts of vinyl-terminated silicone oil 0.5-3 parts of single-walled carbon nanotubes Inhibitor 1-3 parts 15-30 parts of diluent Catalyst 0.9-1 part.

2. The black impact-resistant support tape according to claim 1, characterized in that, The M / Q ratio in the methyl MQ silicone resin is 0.6~0.8; Preferably, the weight-average molecular weight of the methyl MQ silicone resin is 3000-10000 g / mol.

3. The black impact-resistant support tape according to claim 1 or 2, characterized in that, The hydrogen-containing silicone resin contains ≥0.95% active hydrogen by mass. Preferably, the M / Q ratio in the hydrogen-containing silicone resin is 0.6 to 0.8; Preferably, the weight-average molecular weight of the hydrogen-containing silicone resin is 1000~5000 g / mol.

4. The black impact-resistant support tape according to any one of claims 1 to 3, characterized in that, The terminal vinyl silicone oil has the structure shown in Formula I; Formula I; Where a is an integer ≥ 1.

5. The black impact-resistant support tape according to any one of claims 1 to 4, characterized in that, The average particle size of the single-walled carbon nanotubes is 1~5nm; Preferably, the inhibitor comprises any one or a combination of at least two of alkynyl alcohols, vinyl cyclic compounds, polyvinyl silicone oils, and maleate esters.

6. The black impact-resistant support tape according to any one of claims 1 to 5, characterized in that, The diluent includes any one or a combination of at least two of the following: petroleum ether, white spirit, xylene, toluene, n-heptane, ethyl acetate, and cyclohexane; Preferably, the catalyst comprises a platinum catalyst, which includes any one or a combination of at least two of chloroplatinic acid, Karstedt platinum catalyst, and Willing platinum catalyst.

7. The black impact-resistant support tape according to any one of claims 1 to 6, characterized in that, The thickness of the black impact-resistant support tape is 60~80μm.

8. A method for preparing a black impact-resistant support tape according to any one of claims 1 to 7, characterized in that, The preparation method includes: coating an organosilicon optical pressure-sensitive adhesive onto the surface of a substrate and curing it to obtain the black impact-resistant support tape; Preferably, the curing process includes: curing at 80~100℃ for 1~5 min, curing at 110~130℃ for 1~5 min, and then curing at 130~150℃ for 1~5 min.

9. An impact-resistant heat dissipation tape, characterized in that, The impact-resistant heat dissipation tape comprises sequentially stacked metal layers and a black impact-resistant support tape according to any one of claims 1 to 7.

10. An OLED display screen, characterized in that, The OLED display includes the black impact-resistant support tape as described in any one of claims 1 to 7 or the impact-resistant heat dissipation tape as described in claim 9.

Images