A low-tack removable aqueous waste disposal film and method of making same

Abstract

The application provides a low-adhesion removable aqueous waste discharge film, which comprises a substrate and an aqueous pressure-sensitive adhesive layer coated on the surface of the substrate; the aqueous pressure-sensitive adhesive layer comprises the following components by weight parts: aqueous acrylic resin: 100 parts; aziridine curing agent: 0.3-2.0 parts; deionized water: 20-35 parts; defoaming agent: 0.05-0.15 parts; leveling agent: 0.3-1.5 parts; film-forming aid DPM: 0.3-1.2 parts. The application can realize precise controllable adhesion, regulate crosslinking density through the aziridine curing agent, realize 1-10 g / inch wide-width peeling force, adapt to sensitive materials such as mirror surface and OLED, and at the same time, the process is stable and efficient, micro-concave roller coating is combined with multi-stage gradient drying, the uniformity and defect-free of the coating are ensured, and large-scale stable production is supported.

Description

Technical Field

[0001] This invention relates to the field of die-cutting materials technology, specifically to a low-viscosity removable water-based waste removal membrane and its preparation method. Background Technology

[0002] In the die-cutting industry, release film (or protective film) is a key functional material widely used for temporary fixation, protection, and waste removal processes of high-gloss films, mirror materials, easily scratched polishing materials, and extremely fragile electronic films. Its core performance requirement lies in possessing just the right peel force: it must have sufficient initial tack (initial adhesion) to firmly adhere to and remove waste material, while also peeling off easily and without residue, without damaging the expensive or demanding surface of the substrate.

[0003] For a long time, this field has mainly relied on waste discharge membranes based on solvent-based (oil-based) acrylates or rubber-based pressure-sensitive adhesives. While these products are technologically mature, their inherent shortcomings are becoming increasingly prominent with increasingly stringent environmental regulations and ever-increasing precision requirements for end products. 1. Environmental and safety issues: Oil-based pressure-sensitive adhesives typically contain 30%-60% organic solvents such as toluene and ethyl acetate. During coating and drying, these solvents evaporate in large quantities, resulting in the emission of volatile organic compounds (VOCs), which not only pollute the environment but also pose a threat to the health of production personnel.

[0004] 2. Production efficiency bottleneck: The drying speed of oil-based adhesives is severely limited because the evaporation of solvents requires time and energy. Typically, the coating line speed cannot exceed 80-120 meters / minute, and segmented heating in drying tunnels tens of meters long is required, resulting in low production efficiency and high energy consumption.

[0005] 3. Limitations in technical applicability: To meet waste discharge requirements, oil-based adhesives often achieve high initial tack by adjusting the resin molecular weight or the amount of tackifier, but this easily leads to insufficient cohesion. During peeling, the adhesive layer is prone to "cohesive failure," resulting in residual adhesive, ghosting, or migration, especially causing irreversible damage on mirror surfaces and electronic thin films where extremely high cleanliness requirements are required.

[0006] To address these challenges, the industry is gradually shifting towards developing waterborne pressure-sensitive adhesive systems. Waterborne systems use water as the dispersion medium, eliminating VOCs pollution at the source and offering significant advantages in terms of safety, environmental friendliness, and low cost. However, existing publicly available waterborne pressure-sensitive adhesive technologies, especially for demanding wastewater treatment membrane applications, still face a series of technical bottlenecks: A. The balance between initial tack and cohesive force is difficult to coordinate: When water-based acrylic resins are not fully cross-linked, they usually exhibit high tack but weak cohesive force, resulting in easy residue upon peeling. However, increasing the degree of cross-linking to enhance cohesive force often sacrifices initial tack, making the product prone to displacement or detachment during high-speed lamination, which is difficult to meet the requirements of high-precision die-cutting.

[0007] B. Insufficient water resistance and stability: Some water-based adhesives may absorb water and turn white, experience performance degradation or even fail after being stored in humid and hot environments or for a long time, affecting the reliability and shelf life of the product.

[0008] C. Poor process adaptability: Water-based adhesives have a high surface tension, resulting in poor wetting and spreading effects on low surface energy substrates such as PET. If the leveling agent is used improperly, coating defects such as orange peel and pinholes can easily occur. At the same time, the latent heat of vaporization of water is much higher than that of organic solvents, requiring more precise temperature and airflow control during the drying process. Otherwise, the phenomenon of "dry on the surface but not inside" may occur, affecting the final performance.

[0009] In summary, existing water-based pressure-sensitive adhesive technologies still suffer from problems such as difficulty in balancing "adhesion" and "removability," poor water resistance, and narrow process window, and cannot completely replace oil-based products in the application of high-end die-cutting. Summary of the Invention

[0010] The present invention aims to provide a low-viscosity removable aqueous waste membrane and its preparation method, so as to solve the problems of poor environmental performance, inaccurate viscosity control and limited applicable materials in the prior art.

[0011] The technical solution of the present invention is as follows: A low-viscosity, removable, water-based waste-discharging membrane, characterized in that it comprises a substrate and a water-based pressure-sensitive adhesive layer coated on its surface; the water-based pressure-sensitive adhesive layer comprises the following components in parts by weight: Water-based acrylic resin: 100 parts; Aziridine curing agent: 0.3–2.0 parts; Deionized water: 20–35 parts; Defoamer: 0.05–0.15 parts; Leveling agent: 0.3–1.5 parts; Film-forming aid DPM: 0.3–1.2 parts.

[0012] In this invention, waterborne acrylic resin serves as the main adhesive material, providing initial adhesion and cohesive strength. Aziridine curing agent regulates the network density of the adhesive layer through a crosslinking reaction: at low dosages (0.3 parts), the degree of crosslinking is low, resulting in increased peel strength (>10 g / inch), suitable for applications requiring strong fixation; at high dosages (2.0 parts), the crosslinking is dense, molecular chain activity is restricted, and the peel strength decreases to 1-3 g / inch, enabling easy removal. Deionized water serves as an environmentally friendly dispersion medium, replacing organic solvents and eliminating VOC emissions. Defoamers / leveling agents ensure defect-free coating: defoamers inhibit bubble formation, and leveling agents improve the uniformity of adhesive spreading. DPM (dipropylene glycol methyl ether) lowers the minimum film-forming temperature of the resin, promoting continuous film formation at low temperatures.

[0013] Furthermore, the water-based pressure-sensitive adhesive layer comprises the following components in parts by weight: Water-based acrylic resin: 100 parts; Aziridine curing agent: 0.5–1.5 parts; Deionized water: 25–30 parts; Defoamer: 0.08–0.1 parts; Leveling agent: 0.5–1 part; Film-forming aid DPM: 0.5–1 part.

[0014] In this invention, the synergistic effect of waterborne acrylic resin and aziridine curing agent allows the resin to provide basic viscoelasticity and film-forming properties, serving as the "carrier" for performance. The curing agent acts as a "molecular switch," precisely controlling the crosslinking density of the entire polymer network through dosage control. The synergistic effect of deionized water and DPM (dipropylene glycol methyl ether) ensures that after rapid water evaporation, the residual DPM effectively softens the acrylic resin particles, causing them to deform and fuse at a lower temperature (below their minimum film-forming temperature), forming a dense, transparent, and continuous film. If only water is used, the resin particles may not fully fuse, resulting in a discontinuous film with poor performance; if DPM is excessive, the drying speed is too slow, affecting production efficiency. This synergistic effect achieves a smooth and efficient transition from an "aqueous dispersion" to a "high-performance film." Furthermore, the synergistic effect of defoamers and leveling agents, precisely formulated with compatible silicone defoamers and acrylate leveling agents, ensures that a mirror-like smooth adhesive layer is obtained while eliminating bubbles.

[0015] Furthermore, the substrate is a polyester film with a thickness of 40–55 μm, and is pretreated with corona to achieve a surface tension ≥50 dyn / cm.

[0016] In this invention, the polyester film (PET) has high mechanical strength and temperature resistance; corona treatment: the PET surface is polarized by high voltage discharge, increasing the surface energy to ≥50dyn / cm, ensuring the glue wetting and spreading; thickness 40–55μm: too thin and it is easy to deform, too thick and it reduces flexibility and affects waste removal and peeling.

[0017] Furthermore, the defoamer is a silicone-based defoamer or a polyether-based defoamer, and the leveling agent is an acrylate-based leveling agent or a silicone-based leveling agent.

[0018] In this invention, silicone defoamers (such as polydimethylsiloxane) rapidly break bubbles, making them suitable for high-speed coating; polyethers (such as GP type) have good compatibility and are less prone to pinholes. Acrylic leveling agents eliminate orange peel by reducing surface tension; silicones (such as polyether-modified siloxanes) provide slip properties, preventing the twill structure from sticking together.

[0019] Furthermore, the dry adhesive thickness of the water-based pressure-sensitive adhesive layer is 3–8 μm, and the wet adhesive coating amount is 12–25 g / ㎡. The corresponding dry adhesive thickness is precisely controlled by the mesh count of the micro-concave roller.

[0020] Furthermore, the water-based pressure-sensitive adhesive layer is coated with a micro-grooved roller to form a twill structure, wherein the mesh size of the micro-grooved roller is 80–150 mesh. This invention increases the surface area of ​​the adhesive layer through the twill structure, improving initial adhesion uniformity; simultaneously, it forms microchannels to guide the directional release of peel stress during waste removal, preventing damage to brittle materials.

[0021] The present invention also provides a method for preparing the above-mentioned low-viscosity removable aqueous waste membrane, comprising the following steps: (1) Preparation of adhesive: Mix waterborne acrylic resin with deionized water and stir at 300–600 rpm for 5–15 min; add diluted aziridine curing agent and stir at 500–800 rpm for 8–15 min; then add defoamer, leveling agent and DPM, mix evenly and let stand to defoam, and filter through a 3–10 μm filter cartridge. (2) Substrate treatment: The polyester film is subjected to corona treatment after unwinding; (3) Coating and molding: Apply the adhesive to the corona surface using a micro-concave roller; (4) Gradient drying: The product is dried in multiple stages in an oven at 80–150℃. (5) Rewinding and slitting: Rewind at a speed of 150–300 m / min.

[0022] In this invention, after all components are proportioned, they are combined with "micro-grooved roller coating" and "multi-stage gradient drying" processes for synergistic effect. Good leveling properties ensure accurate transfer of the twill structure; precise crosslinking reaction is fully carried out under gradient heating; and the stepwise evaporation of DPM and water is completed smoothly under gradient cooling, avoiding the accumulation of internal stress.

[0023] Furthermore, the drying temperature gradient in step (4) includes temperature zones of 80–100℃, 100–120℃, 120–140℃, and 140–150℃, with a total drying time of 30–90 seconds. Preferably, the gradient drying in step (4) includes sequentially passing through an oven at 90℃, 100℃, 125℃, 140℃, 140℃, 130℃, 120℃, 100℃, 80℃, 70℃, and 60℃, with a blower strength of 70–90% and an exhaust strength of 0–50%.

[0024] In this invention, the heating stage (80–150℃) gradually evaporates moisture, preventing boiling and the formation of bubbles / orange peel-like texture; the cooling stage (140℃→60℃): the high-temperature zone (140℃) completes the cross-linking reaction, enhancing cohesion; the stepped cooling stage: each stage cools by 10–20℃, allowing the adhesive layer molecular chains to slowly relax, eliminating internal stress and preventing curling and deformation. Airflow control: 70–90% airflow enhances heat transfer, while 0–50% airflow regulates humidity to prevent skin formation.

[0025] Furthermore, in step (3), the coating speed is 180–280 m / min, and the wet adhesive amount after coating is 12–25 g / m².

[0026] The aforementioned low-viscosity, removable, water-based waste removal membrane is used in die-cutting processes for temporary fixation and waste removal of mirror films, high-gloss materials, easily scratched polishing materials, or fragile electronic films.

[0027] The beneficial effects of this invention are as follows: 1. Significant environmental and economic benefits: Replacing organic solvents with deionized water completely eliminates VOC emissions, eliminates the need for expensive waste gas treatment equipment, and reduces the risk of fire; the coating line speed is increased and efficiency is significantly improved, while drying energy consumption is greatly reduced.

[0028] 2. Precise and controllable adhesion with wide applicability: By precisely controlling the crosslinking density through the dosage of aziridine curing agent, a wide range of peel force adjustment from 1 to 10 g / inch can be achieved to meet the stringent adhesion requirements of different materials such as mirrors, high gloss, and OLED films, avoiding residual adhesive or substrate damage.

[0029] 3. Excellent and reliable product performance: The moderately cross-linked network ensures that the peeling is an interfacial separation rather than cohesive destruction, eliminating residual adhesive; the twill structure improves the initial tack and guides stress release, making peeling smoother; the cross-linked structure enhances water resistance and aging resistance.

[0030] 4. Stable and efficient production process: Micro-grooved roller coating ensures consistency in adhesive layer thickness and coating amount; multi-stage gradient drying avoids defects such as bubbles and orange peel, ensuring high product quality and batch stability, supporting large-scale industrial production. Specific Implementation

[0031] The technical solutions will now be clearly and completely described in conjunction with embodiments of the present invention. Obviously, the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention. Example 1

[0032] A low-viscosity, removable, water-based waste-discharging membrane, characterized in that it comprises a substrate and a water-based pressure-sensitive adhesive layer coated on its surface; the water-based pressure-sensitive adhesive layer comprises the following components in parts by weight: Water-based acrylic resin: 100 parts Aziridine curing agent: 0.3 parts Deionized water: 20 parts Organosilicon defoamer: 0.05 parts Acrylic leveling agent: 0.3 parts Film-forming aid DPM: 0.3 parts.

[0033] Furthermore, the substrate is a polyester film with a thickness of 40 μm, and is pretreated with corona to achieve a surface tension ≥50 dyn / cm.

[0034] Furthermore, the defoamer is a silicone-based defoamer or a polyether-based defoamer, and the leveling agent is an acrylate-based leveling agent or a silicone-based leveling agent.

[0035] Furthermore, the dry adhesive thickness of the water-based pressure-sensitive adhesive layer is 3 μm, and the wet adhesive coating amount is 12 g / ㎡.

[0036] Furthermore, the water-based pressure-sensitive adhesive layer is coated with a micro-grooved roller to form a twill structure, and the micro-grooved roller has a mesh size of 80 mesh. Example 2

[0037] A low-viscosity, removable, water-based waste-discharging membrane, characterized in that it comprises a substrate and a water-based pressure-sensitive adhesive layer coated on its surface; the water-based pressure-sensitive adhesive layer comprises the following components in parts by weight: Water-based acrylic resin: 100 parts Aziridine curing agent: 0.5 parts Deionized water: 34 parts Polyether defoamer: 0.15 parts Organosilicon leveling agent: 1.5 parts Film-forming aid DPM: 0.4 parts.

[0038] Furthermore, the substrate is a polyester film with a thickness of 42 μm, and is pretreated with corona to achieve a surface tension ≥50 dyn / cm.

[0039] Furthermore, the defoamer is a silicone-based defoamer or a polyether-based defoamer, and the leveling agent is an acrylate-based leveling agent or a silicone-based leveling agent.

[0040] Furthermore, the dry adhesive thickness of the water-based pressure-sensitive adhesive layer is 7 μm, and the wet adhesive coating amount is 24 g / ㎡.

[0041] Furthermore, the water-based pressure-sensitive adhesive layer is coated with a micro-grooved roller to form a twill structure, and the micro-grooved roller has a mesh size of 90 mesh. Example 3

[0042] A low-viscosity, removable, water-based waste-discharging membrane, characterized in that it comprises a substrate and a water-based pressure-sensitive adhesive layer coated on its surface; the water-based pressure-sensitive adhesive layer comprises the following components in parts by weight: Water-based acrylic resin: 100 parts Aziridine curing agent: 1.0 part Deionized water: 28 parts Organosilicon defoamer: 0.08 parts Acrylic leveling agent: 0.8 parts Film-forming aid DPM: 0.8 parts.

[0043] Furthermore, the substrate is a polyester film with a thickness of 50 μm, and is pretreated with corona to achieve a surface tension ≥50 dyn / cm.

[0044] Furthermore, the defoamer is a silicone-based defoamer or a polyether-based defoamer, and the leveling agent is an acrylate-based leveling agent or a silicone-based leveling agent.

[0045] Furthermore, the dry adhesive thickness of the water-based pressure-sensitive adhesive layer is 5 μm, and the wet adhesive coating amount is 18 g / ㎡.

[0046] Furthermore, the water-based pressure-sensitive adhesive layer is coated with a micro-grooved roller to form a twill structure, and the micro-grooved roller has a mesh size of 120 mesh. Example 4

[0047] A low-viscosity, removable, water-based waste-discharging membrane, characterized in that it comprises a substrate and a water-based pressure-sensitive adhesive layer coated on its surface; the water-based pressure-sensitive adhesive layer comprises the following components in parts by weight: Water-based acrylic resin: 100 parts Aziridine curing agent: 1.2 parts Deionized water: 35 parts Polyether defoamer: 0.1 parts Organosilicon leveling agent: 1.0 part Film-forming aid DPM: 1.0 part.

[0048] Furthermore, the substrate is a polyester film with a thickness of 55 μm, and is pretreated with corona to achieve a surface tension ≥50 dyn / cm.

[0049] Furthermore, the defoamer is a silicone-based defoamer or a polyether-based defoamer, and the leveling agent is an acrylate-based leveling agent or a silicone-based leveling agent.

[0050] Furthermore, the dry adhesive thickness of the water-based pressure-sensitive adhesive layer is 6 μm, and the wet adhesive coating amount is 25 g / ㎡.

[0051] Furthermore, the water-based pressure-sensitive adhesive layer is coated with a micro-grooved roller to form a twill structure, and the micro-grooved roller has a mesh count of 100 mesh. Example 5

[0052] A low-viscosity, removable, water-based waste-discharging membrane, characterized in that it comprises a substrate and a water-based pressure-sensitive adhesive layer coated on its surface; the water-based pressure-sensitive adhesive layer comprises the following components in parts by weight: Water-based acrylic resin: 100 parts Aziridine curing agent: 1.8 parts Deionized water: 22 parts Organosilicon defoamer: 0.06 parts Acrylic leveling agent: 0.4 parts Film-forming aid DPM: 1.2 parts.

[0053] Furthermore, the substrate is a polyester film with a thickness of 45 μm, and is pretreated with corona to achieve a surface tension ≥50 dyn / cm.

[0054] Furthermore, the defoamer is a silicone-based defoamer or a polyether-based defoamer, and the leveling agent is an acrylate-based leveling agent or a silicone-based leveling agent.

[0055] Furthermore, the dry adhesive thickness of the water-based pressure-sensitive adhesive layer is 4 μm, and the wet adhesive coating amount is 15 g / ㎡.

[0056] Furthermore, the water-based pressure-sensitive adhesive layer is coated with a micro-grooved roller to form a twill structure, and the micro-grooved roller has a mesh size of 150. Example 6

[0057] A low-viscosity, removable, water-based waste-discharging membrane, characterized in that it comprises a substrate and a water-based pressure-sensitive adhesive layer coated on its surface; the water-based pressure-sensitive adhesive layer comprises the following components in parts by weight: Water-based acrylic resin: 100 parts Aziridine curing agent: 2.0 parts Deionized water: 30 parts Polyether defoamer: 0.09 parts Organosilicon leveling agent: 0.6 parts Film-forming aid DPM: 0.6 parts.

[0058] Furthermore, the substrate is a polyester film with a thickness of 48 μm, and is pretreated with corona to achieve a surface tension ≥50 dyn / cm.

[0059] Furthermore, the defoamer is a silicone-based defoamer or a polyether-based defoamer, and the leveling agent is an acrylate-based leveling agent or a silicone-based leveling agent.

[0060] Furthermore, the dry adhesive thickness of the water-based pressure-sensitive adhesive layer is 8 μm, and the wet adhesive coating amount is 20 g / ㎡.

[0061] Furthermore, the water-based pressure-sensitive adhesive layer is coated with a micro-grooved roller to form a twill structure, and the micro-grooved roller has a mesh size of 110. Example 7

[0062] A method for preparing a low-viscosity, removable, water-based waste membrane includes the following steps: (1) Preparation of adhesive: Mix waterborne acrylic resin with deionized water and stir at 450 rpm for 8 min; add diluted aziridine curing agent and stir at 650 rpm for 10 min; then add defoamer, leveling agent and DPM, mix evenly and let stand to defoam, and filter through 3–10 μm filter cartridge. (2) Substrate treatment: The polyester film is subjected to corona treatment after unwinding; (3) Coating and molding: Apply the adhesive to the corona surface using a micro-concave roller; (4) Gradient drying: The product is dried in multiple stages in an oven at 80–150℃. (5) Rewinding and slitting: Rewind at a speed of 250 m / min.

[0063] Furthermore, the drying temperature gradient in step (4) includes temperature zones of 80–100℃, 100–120℃, 120–140℃, and 140–150℃, with a total drying time of 60 seconds. The gradient drying in step (4) includes passing through ovens at temperatures of 90℃, 100℃, 125℃, 140℃, 140℃, 130℃, 120℃, 100℃, 80℃, 70℃, and 60℃ in sequence, with a forced draft intensity of 80% and an exhaust intensity of 30%.

[0064] Furthermore, in step (3), the coating speed is 230 m / min, and the wet adhesive amount after coating is 12–25 g / m². Example 8

[0065] A method for preparing a low-viscosity, removable, water-based waste membrane includes the following steps: (1) Preparation of adhesive: Mix waterborne acrylic resin with deionized water and stir at 300 rpm for 15 min; add diluted aziridine curing agent and stir at 500 rpm for 15 min; then add defoamer, leveling agent and DPM, mix evenly and let stand to defoam, and filter through 3–10 μm filter cartridge. (2) Substrate treatment: The polyester film is subjected to corona treatment after unwinding; (3) Coating and molding: Apply the adhesive to the corona surface using a micro-concave roller; (4) Gradient drying: The product is dried in multiple stages in an oven at 80–150℃. (5) Rewinding and slitting: Rewind at a speed of 150 m / min.

[0066] Furthermore, in step (4), the drying temperature gradient includes temperature zones of 80℃, 100℃, 120℃, and 140℃, and the total drying time is 90 seconds. The blower intensity is 70%, and the exhaust intensity is 10%.

[0067] Furthermore, in step (3), the coating speed is 180 m / min, and the wet adhesive amount after coating is 12–25 g / m². Example 9

[0068] A method for preparing a low-viscosity, removable, water-based waste membrane includes the following steps: (1) Preparation of adhesive: Mix waterborne acrylic resin with deionized water and stir at 600 rpm for 5 min; add diluted aziridine curing agent and stir at 800 rpm for 8 min; then add defoamer, leveling agent and DPM, mix evenly and let stand to defoam, and filter through 3–10 μm filter cartridge. (2) Substrate treatment: The polyester film is subjected to corona treatment after unwinding; (3) Coating and molding: Apply the adhesive to the corona surface using a micro-concave roller; (4) Gradient drying: The product is dried in multiple stages in an oven at 80–150℃. (5) Rewinding and slitting: Rewind at a speed of 300m / min.

[0069] Furthermore, in step (4), the drying temperature gradient includes temperature zones of 100℃, 120℃, 140℃, and 150℃, and the total drying time is 30 seconds. The blowing intensity is 90%, and the exhaust intensity is 50%.

[0070] Furthermore, in step (3), the coating speed is 280 m / min, and the wet adhesive amount after coating is 12–25 g / m².

[0071] Comparative Example 1 A waste discharge membrane using a traditional oil-based system, specifically: Substrate: 50μm thick polyester film, corona-treated surface tension ≥50dyn / cm.

[0072] Pressure-sensitive adhesive layer formulation: Oil-based acrylic resin: 100 parts Ethyl acetate (solvent): 50 parts Isocyanate curing agent: 5 parts Defoamer: 0.1 parts.

[0073] Preparation process: Coating is performed using the same micro-grooved roller (120 mesh), with a wet coating amount of 18 g / m². The drying process requires extending the drying time to 120-180 seconds in an oven at 80-150℃ to ensure complete solvent evaporation, and the winding speed is reduced to 80-100 m / min.

[0074] Comparative Example 2 This comparative example uses the same low-viscosity removable water-based waste membrane as Example 3, except that aziridine curing agent is not used.

[0075] Comparative Example 3 This comparative example uses the same low-viscosity removable water-based waste-discharging membrane as Example 3. The difference is that the coating method uses traditional doctor blade coating instead of micro-groove roller coating. The preparation method is the same as in Example 7, except that the drying process uses a single-temperature oven at 120°C instead of the multi-stage gradient drying in Example 7.

[0076] The waste discharge membranes of Examples 1-6 and Comparative Example 2 were prepared according to the method of Example 7, and their performance was tested. The specific test methods are as follows: Peel force: The two separated ends were clamped onto the testing machine fixtures and peeled at a speed of 200±20 mm / min. The maximum peel force was recorded. Residual adhesive rate: After 180° peeling, observe the surface of the adhered object with the naked eye or an optical microscope; Temperature resistance: High and low temperature cycling (-20℃ to 80℃, 24h); Material compatibility: After bonding with mirror stainless steel, high-gloss acrylic, OLED film, etc. for 24 hours, the materials were removed. Test results are shown in Tables 1 and 2.

[0077] Table 1

[0078] Table 2

[0079] As shown in Table 2, in Comparative Example 1, the formation of microporous structures due to solvent evaporation led to stress concentration and residual adhesive. The residual solvent, acting as a plasticizer, reduced the temperature resistance and caused swelling and erosion of the engineering plastics. In Comparative Example 2, the lack of network constraints in the linear molecular chains caused creep and thermal collapse of the adhesive layer at 40°C, resulting in the complete transfer of the adhesive to the substrate. In Comparative Example 3, the fluctuation in the thickness of the doctor blade coating caused the peel force to become discrete. The single drying process resulted in surface dryness and internal wetness, uneven cross-linking, and ultimately caused bubbles, embrittlement, and compatibility fluctuations.

[0080] In particular, the performance tests of the above embodiments and comparative examples are all based on existing testing methods in the art, and are conducted using the same test parameters and evaluation indicators.

[0081] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0082] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that can be understood by those skilled in the art. It should be noted that any technical features not described in detail in this invention can be implemented using any existing technology.

Claims

1. A low-viscosity, removable, water-based waste membrane, characterized in that, It includes a substrate and an aqueous pressure-sensitive adhesive layer coated on its surface; the aqueous pressure-sensitive adhesive layer comprises the following components in parts by weight: Water-based acrylic resin: 100 parts; Aziridine curing agent: 0.3–2.0 parts; Deionized water: 20–35 parts; Defoamer: 0.05–0.15 parts; Leveling agent: 0.3–1.5 parts; Film-forming aid DPM: 0.3–1.2 parts.

2. The low-viscosity removable aqueous waste membrane according to claim 1, characterized in that, The water-based pressure-sensitive adhesive layer comprises the following components in parts by weight: Water-based acrylic resin: 100 parts; Aziridine curing agent: 0.5–1.5 parts; Deionized water: 25–30 parts; Defoamer: 0.08–0.1 parts; Leveling agent: 0.5–1 part; Film-forming aid DPM: 0.5–1 part.

3. The low-viscosity removable aqueous waste membrane according to claim 1 or 2, characterized in that, The substrate is a polyester film with a thickness of 40–55 μm, and is pretreated with corona to achieve a surface tension ≥50 dyn / cm.

4. The low-viscosity removable aqueous waste membrane according to claim 1 or 2, characterized in that, The defoamer is a silicone-based defoamer or a polyether-based defoamer, and the leveling agent is an acrylate-based leveling agent or a silicone-based leveling agent.

5. The low-viscosity removable aqueous waste membrane according to claim 1 or 2, characterized in that, The dry adhesive thickness of the water-based pressure-sensitive adhesive layer is 3–8 μm, and the wet adhesive coating amount is 12–25 g / m².

6. The low-viscosity removable aqueous waste membrane according to claim 1 or 2, characterized in that, The water-based pressure-sensitive adhesive layer is coated with a micro-grooved roller to form a twill structure, wherein the mesh size of the micro-grooved roller is 80–150 mesh.

7. A method for preparing a low-viscosity, removable aqueous waste membrane according to any one of claims 1-6, characterized in that, Includes the following steps: (1) Preparation of adhesive: Mix waterborne acrylic resin with deionized water and stir at 300–600 rpm for 5–15 min; add diluted aziridine curing agent and stir at 500–800 rpm for 8–15 min; then add defoamer, leveling agent and DPM, mix evenly and let stand to defoam, and filter through a 3–10 μm filter cartridge. (2) Substrate treatment: The polyester film is subjected to corona treatment after unwinding; (3) Coating and molding: Apply the adhesive to the corona surface using a micro-concave roller; (4) Gradient drying: The product is dried in multiple stages in an oven at 80–150℃. (5) Rewinding and slitting: Rewind at a speed of 150–300 m / min.

8. The preparation method according to claim 7, characterized in that, The drying temperature gradient in step (4) includes temperature zones of 80–100℃, 100–120℃, 120–140℃, and 140–150℃, with a total drying time of 30–90 seconds. Preferably, the gradient drying in step (4) includes sequentially passing through an oven at 90℃, 100℃, 125℃, 140℃, 140℃, 130℃, 120℃, 100℃, 80℃, 70℃, and 60℃, with a blower strength of 70–90% and an exhaust strength of 0–50%.

9. The preparation method according to claim 8, characterized in that, In step (3), the coating speed is 180–280 m / min, and the wet adhesive amount after coating is 12–25 g / m².

10. The low-viscosity removable waterborne waste removal membrane according to any one of claims 1–7 is used in die-cutting processes for temporary fixation and waste removal of mirror films, high-gloss materials, easily scratched polishing materials or fragile electronic films.

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