Grid release film, preparation method thereof and adhesive tape

Abstract

The invention provides a grid release film, a preparation method thereof and an adhesive tape. The invention relates to the technical field of release films. The grid release film comprises a base material layer and a resin grid layer which are sequentially stacked from bottom to top, and a grid structure is formed on the side, away from the base material layer, of the resin grid layer; the grid structure is formed by connecting a plurality of hexagonal grids, pressing groove protruding strips formed between the adjacent hexagonal grids intersect at the vertex angle positions of the hexagonal grids to form a node structure, and the diameter of the circumcircle of the node structure is 15-30 microns. When the size of the node structures on the grid structure of the grid release film is limited within the range of 15-30 microns, the node structures can be matched with the width and depth of the groove pressing convex strips, bubbles in the grid-shaped exhaust grooves formed in the pressure-sensitive adhesive can be rapidly exhausted, and the exhaust grooves can disappear within the preset time.

Description

Technical Field

[0001] The present disclosure relates to the technical field of release films, and in particular to a grid release film and a preparation method and an adhesive tape thereof. Background Art

[0002] The preparation method of the mesh release film on the current market generally includes first melting PE particles, then coating on the surface of the substrate, embossing, cooling to form a mesh layer on the surface of the substrate, and then coating the surface of the mesh layer with a release agent to form a release layer on the mesh layer. Another example is an embossed release film disclosed in a Chinese patent application (CN106273956A), which includes a substrate layer, a coating layer and a release layer; the coating layer is arranged on the substrate layer, and a texture is formed on the surface of the coating layer; the release layer is arranged on the coating layer and matches and fits with the texture; the coating layer is a polyethylene layer or a polypropylene layer.

[0003] However, this grid layer / laminated layer made of PE material (maximum temperature resistance 90°C) is not resistant to high temperatures. Therefore, when the grid release film and pressure-sensitive adhesive are prepared to form an application product (such as a tape), since the general drying temperature of the adhesive is above 100°C, when the adhesive is coated on the release layer and dried, the grid embossing on the surface of the release film will be deformed, resulting in the grid-like exhaust grooves formed on the pressure-sensitive adhesive to be of varying depths and unstable exhaust effect.

[0004] In addition, we also found that the grid layer structure of the grid release film is generally a quadrilateral grid structure, and the corresponding exhaust grooves formed on the pressure-sensitive adhesive are quadrilateral exhaust grooves. However, we found that when the pressure-sensitive adhesive is actually attached to the surface of the adhered object, the bubbles in the exhaust grooves cannot be eliminated and the exhaust grooves cannot disappear within the preset time. In other words, the exhaust effect and disappearance effect of the exhaust grooves are not good, which not only affects the production rhythm, but also affects the appearance and performance of the adhered objects, and also requires additional equipment to eliminate bubbles, which undoubtedly increases production costs and reduces production efficiency. Summary of the invention

[0005] The present disclosure provides a grid release film and a preparation method thereof and an adhesive tape, so as to at least solve one of the technical problems existing in the prior art.

[0006] According to the first aspect of the present disclosure, the present invention provides a grid release film, comprising a substrate layer and a resin grid layer stacked in sequence from bottom to top, the resin grid layer forming a grid structure on the side away from the substrate layer; the grid structure is composed of a plurality of hexagonal grids connected to each other, and the grooved convex strips formed between adjacent hexagonal grids intersect at the top corners of the hexagonal grids to form a node structure, and the circumscribed circle diameter of the node structure is 15~30μm.

[0007] In one possible implementation manner, the depth of the groove convex strip is 5-10 μm, and the width of the groove convex strip is 19-25 μm.

[0008] In one possible implementation, the resin grid layer is configured to be able to remain unchanged at at least 100° C., and the resin grid layer is formed by photocuring of UV resin liquid.

[0009] In one embodiment, the UV resin liquid includes the following raw materials in parts by weight: 100 parts of UV glue, 3 to 12 parts of UV crosslinking agent, and 3 to 4 parts of UV initiator; wherein the UV crosslinking agent is a mixture of one or more of a bifunctional UV crosslinking agent, a trifunctional UV crosslinking agent, and a tetrafunctional UV crosslinking agent.

[0010] In one embodiment, the bifunctional UV crosslinking agent is a mixture of one or more of polyethylene glycol 400 diacrylate, 1,6-hexanediol diacrylate, and polyurethane modified diacrylate oligomer; The trifunctional UV crosslinking agent is a mixture of one or more of trimethylolpropane tris[3-(2-methylaziridinyl)propionate], trimethylolpropane triacrylate, and pentaerythritol triacrylate; The tetrafunctional UV crosslinking agent is a mixture of one or more of pentaerythritol tetraallyl ether and tetrafunctional polyester acrylate; The UV initiator is a mixture of one or more of 1-hydroxycyclohexyl phenyl ketone, diphenyl-(2,4,6-trimethylbenzoyl)phosphine oxide, 2-isopropylthioxanthone and isopropylthioxanthone.

[0011] In one possible implementation manner, a release layer is further included, and the release layer is stacked on the grid structure of the resin grid layer.

[0012] According to a second aspect of the present disclosure, the present invention provides a method for preparing a grid release film, which is applied to the grid release film, and the preparation method comprises: The UV resin liquid is transferred and coated onto the surface of the substrate layer by an anilox roller, and then UV initial curing is performed, thereby initially forming a resin grid layer with a grid structure on the surface of the substrate layer. The UV exposure during the UV initial curing is 500-2000 mj / cm 2 ; The substrate layer with the resin grid layer formed on the surface is subjected to UV secondary curing molding; wherein the UV exposure during UV secondary curing is 500~2000 mj / cm 2 .

[0013] In one embodiment, the UV resin liquid includes the following raw materials in parts by weight: 100 parts of UV glue, 3 to 12 parts of UV crosslinking agent, and 3 to 4 parts of UV initiator; wherein the UV crosslinking agent is a mixture of one or more of a bifunctional UV crosslinking agent, a trifunctional UV crosslinking agent, and a tetrafunctional UV crosslinking agent.

[0014] In one possible implementation, the preparation method further comprises: coating a release agent on the surface of the grid structure of the resin grid layer to form a release layer.

[0015] According to a third aspect of the present disclosure, there is provided an adhesive tape comprising the grid release film or the grid release film prepared by the method described.

[0016] Compared with the prior art, the advantages of the present application are: 1) when the size of the node structure on the grid structure of the grid release film of the present application is limited to the range of 15~30μm, it can be coordinated with the width and depth of the groove ridges, so that the bubbles in the grid-shaped exhaust grooves formed on the pressure-sensitive adhesive can be quickly discharged, and the exhaust grooves can also disappear within a preset time.

[0017] 2) The resin mesh layer of the present application is formed by UV resin liquid light curing, so that the resin mesh layer is resistant to high temperature (it can be kept at 90-150°C without deformation, and can even remain unchanged at above 150°C). Therefore, when the adhesive is coated on the mesh release film and dried to form a pressure-sensitive adhesive layer, it can ensure that the entire mesh release film does not deform, and the mesh structure does not deform, thereby ensuring that the depth of the exhaust groove formed on the surface of the pressure-sensitive adhesive is consistent, and ensuring the exhaust stability and disappearance of the exhaust groove.

[0018] 3) This application adopts a coating process, which has more advantages in controlling size and appearance than the existing conventional laminating process. The UV curing embossing molding is faster and more thorough, and the depth and width data of the formed grid structure are more stable.

[0019] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present disclosure, nor is it intended to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and other purposes, features and advantages of the exemplary embodiments of the present disclosure will become readily understood by reading the detailed description below with reference to the accompanying drawings. In the accompanying drawings, several embodiments of the present disclosure are shown in an exemplary and non-limiting manner, in which: In the drawings, the same or corresponding reference numerals represent the same or corresponding parts.

[0021] Figure 1 A schematic structural diagram of a grid release film according to an embodiment of the present disclosure is shown; Figure 2 A top view of the grid release film of an embodiment of the present disclosure under a microscope is shown; Figure 3 A schematic diagram of a node structure formed by the intersection of grooves and convex strips in the grid structure of the grid release film of an embodiment of the present disclosure is shown; Figure 4 A schematic diagram showing the grid structure of the grid release film of the embodiment of the present disclosure and the arrangement of the conventional quadrilateral grid structure at present; Figure 5 The node structure formed by the intersection of the grooves and convex strips in the first case of the embodiment of the present disclosure is shown; Figure 6 The node structure formed by the intersection of the grooves and convex strips in the second case of the embodiment of the present disclosure is shown; Figure 7 The node structure formed by the intersection of the pressed grooves and convex strips in the third case of the embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0022] In order to make the purpose, features, and advantages of the present disclosure more obvious and easy to understand, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, not all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present disclosure.

[0023] Since the grid release film currently on the market cannot directly coat the pressure-sensitive adhesive on the release layer under high temperature conditions, the surface of the grid release film will be deformed when the adhesive is coated, which will lead to inconsistent depths of the grid-shaped exhaust grooves formed on the surface of the pressure-sensitive adhesive, and unstable exhaust effect. Moreover, after the structure and size of the grid structure of the current grid release film are transferred to the pressure-sensitive adhesive, when the pressure-sensitive adhesive is attached to the surface of the object to be attached, the bubbles generated in the exhaust grooves cannot be eliminated, and the exhaust grooves cannot disappear within the preset time, which affects the appearance and performance of the attached object.

[0024] Based on the above problems, the applicant has conducted creative research and experiments to improve the preparation materials, preparation process and grid structure of the grid release film. This not only solves the problem of stably coating adhesive on the grid release film under high temperature conditions, but also solves the problem that when the grid release film is specifically compounded with the pressure-sensitive adhesive to prepare the application product (such as tape), the depth of the grid-shaped exhaust grooves on the pressure-sensitive adhesive can be made consistent. When the pressure-sensitive adhesive is bonded to the attached object (such as mobile phones and other electronic products), the bubbles can be quickly discharged, and the exhaust grooves on the pressure-sensitive adhesive surface can disappear in a short time without affecting the appearance and performance of the attached object.

[0025] Based on this, according to the first aspect of the present invention, the present application first provides a grid release film.

[0026] like Figure 1-3 As shown, a grid release film comprises a substrate layer 1 and a resin grid layer 2 stacked in sequence from bottom to top, and the resin grid layer 2 is formed with a grid structure 3 on the side away from the substrate layer 1; the grid structure 3 is composed of a plurality of uniformly arranged hexagonal grids 31 connected to each other, and a groove convex strip 32 is formed between adjacent hexagonal grids 31, and the groove convex strips 32 between adjacent hexagonal grids intersect at the vertex position of the hexagonal grid to form a node structure 33, and the node structure 33 is generally triangular in shape, and the diameter of the circumscribed circle of the node structure is 15~30μm. Exemplarily, the diameter of the circumscribed circle of the node structure can be 15μm, 20μm, 25μm, and 30μm. For example, in the present application, the so-called "circumscribed circle of the node structure" is the circumscribed circle of a virtual triangle formed by the connecting line between the vertex angles of each adjacent hexagon at the intersection position. In other words, the so-called "circumscribed circle of the node structure" is the circumscribed circle of a virtual triangle formed by the wide sides (in the width direction) of adjacent groove convex strips at the intersection position.

[0027] For example, Figure 3 As shown, the hexagonal grid in this embodiment may be a regular hexagon, and the side length of the hexagonal grid is 160-180 um.

[0028] For example, Figure 1 As shown, in this embodiment, the resin grid layer 2 includes a resin plane layer 21 and a grid structure 3. The resin plane layer 21 is arranged close to one side of the substrate layer 1, and the grid structure 3 is arranged on the side of the resin plane layer 21 away from the substrate layer, and the grid structure 3 protrudes from the resin plane layer 21.

[0029] like Figure 1-2As shown, in the present application, the side of the resin mesh layer 2 facing away from the substrate layer is a mesh structure in a mesh shape, and the mesh structure 3 is composed of a plurality of uniformly arranged hexagonal meshes 31 connected to each other, and these hexagonal meshes 31 are substantially arranged and connected to each other in the order of the hexagonal shape through the grooved convex strips 32, so that adjacent hexagonal meshes 31 share a grooved convex strip 32. The grooved convex strips 32 between adjacent hexagonal meshes intersect at the vertex position of the hexagon to form a node structure 33, and these grooved convex strips 32 are connected to each other through the node structure. Therefore, when the pressure-sensitive adhesive is stacked on the surface of the grid release film, these grooved convex strips 32 on the grid structure 3 can form corresponding grid-shaped hexagonal exhaust grooves on the surface of the pressure-sensitive adhesive. These exhaust grooves also intersect at the apex corners of the hexagon to form exhaust nodes (when the node structure of the grid release film is transferred to the pressure-sensitive adhesive layer, exhaust nodes will be formed on the surface of the pressure-sensitive adhesive layer). After the grid release film is peeled off from the pressure-sensitive adhesive, the pressure-sensitive adhesive as a whole has the grid-shaped exhaust grooves, so when the pressure-sensitive adhesive is attached to the object, the bubbles in the exhaust grooves can be quickly discharged and the exhaust grooves can disappear within a preset time.

[0030] In the present application, the grid structure 3 on the grid release film is composed of hexagonal grids 31 as units connected to each other. We found that, compared with the quadrilateral grid structure on the conventional release film, under the same conditions, the more edges the polygonal grid has, the more exhaust nodes the exhaust grooves formed on the surface of the pressure-sensitive adhesive have, and the exhaust effect is positively correlated. Since the grid structure 3 is formed by transferring the resin liquid to the surface of the substrate layer using an anilox roller, it is necessary to first engrave a pattern corresponding to the grid structure on the anilox roller. Considering the difficulty of implementing the pattern on the anilox roller, a hexagonal grid is preferably used.

[0031] When the exhaust grooves formed on the surface of the pressure-sensitive adhesive are attached to the adhered object, most of the bubbles in the exhaust grooves are gathered at the exhaust node positions. This causes the mesh release film on the market to form exhaust grooves on the surface of the pressure-sensitive adhesive after being attached to the adhered object. When the exhaust grooves are actually attached to the adhered object, the bubbles in the exhaust grooves cannot be discharged and the exhaust grooves cannot disappear within the preset time. After a lot of research and experiments, it was found that when the size of the node structure on the mesh structure of the mesh release film (i.e., the circumscribed circle diameter of the node structure) is limited to the range of 15~30μm, it can be matched with the width and depth of the groove convex strips, so that the bubbles in the exhaust grooves on the pressure-sensitive adhesive can be quickly discharged, and the exhaust grooves can also disappear within the preset time.

[0032] In this embodiment, when the grid structure 3 is composed of a plurality of uniformly arranged hexagonal grids 31 connected to each other, the corresponding exhaust grooves formed on the surface of the pressure-sensitive adhesive are hexagonal exhaust grooves, and these hexagonal exhaust grooves are connected to each other through exhaust nodes, thereby forming a grid shape. Under the same conditions, the number of hexagonal exhaust grooves and exhaust nodes are more than the conventional quadrilateral exhaust grooves, and the more exhaust grooves and exhaust nodes, the better the exhaust effect, so the hexagonal exhaust grooves are better than the quadrilateral exhaust grooves in exhaust effect.

[0033] For example, when the grid structure on the grid release film is transferred to the pressure-sensitive adhesive, it corresponds to the shape of the exhaust groove formed. Figure 4 As shown, in this embodiment, we take the grid structure 3 composed of hexagonal grids 31 as an example, and compare them with the conventional grid structure composed of quadrilateral grids on the market, and analyze the hexagonal grid-shaped exhaust grooves and quadrilateral grid-shaped exhaust grooves formed by transferring them to the surface of the pressure-sensitive adhesive. We select hexagonal exhaust grooves and quadrilateral exhaust grooves with the same conditions and the same area for arrangement. It turns out that the rule for increasing exhaust nodes is (the number and exhaust node rule of quadrilateral exhaust grooves and hexagonal exhaust grooves as shown in Table 1): 1) When the number of quadrilateral exhaust grooves increases to an odd number, add one exhaust node. When the number of quadrilateral exhaust grooves increases to an even number, add two exhaust nodes. 2) As long as the number of hexagonal exhaust grooves increases by one, the corresponding exhaust nodes will increase by two. Therefore, the grid release film needs to choose a polygonal graphic, and the following two points need to be achieved: First, it can be densely arranged without blank areas, and the exhaust grooves form a continuous channel without breakpoints. Second, the number of exhaust grooves and exhaust nodes should be as many as possible. Therefore, the hexagonal venting groove is the best choice to meet these two points. Accordingly, on the mesh release film, the hexagonal mesh is the best choice for the polygonal mesh forming the mesh structure.

[0034] Table 1 Number and exhaust node rules of conventional quadrilateral exhaust slots and hexagonal exhaust slots of the present application

[0035] Further, such as Figure 1 As shown, the mesh release film of this embodiment further includes a release layer 4, and the release layer 4 is stacked on the mesh structure 3 of the resin mesh layer. That is, the mesh structure 3 is formed on the side where the resin mesh layer 2 of the mesh release film contacts the release layer 4, and the release layer 4 is stacked on the mesh structure 3.

[0036] When a pressure-sensitive adhesive is coated on the grid release film to further prepare an application product (such as a tape), a release layer will be first provided on the resin grid layer to ensure that the grid release film can be peeled off from the pressure-sensitive adhesive. The thickness of the release layer 4 is generally 0.5~1μm. Compared with the grid structure, the thickness of the release film can be ignored. Therefore, when the grid release film composed of the substrate layer, the resin grid layer and the release layer is compounded with the pressure-sensitive adhesive, the grid structure can be transferred to the pressure-sensitive adhesive, so that the corresponding grid-shaped hexagonal exhaust grooves are formed on the surface of the pressure-sensitive adhesive. The depth, width and exhaust nodes of the exhaust grooves on the pressure-sensitive adhesive are comparable to the depth, width and node structure dimensions of the groove convex strips of the grid structure.

[0037] For example, the material of the substrate layer is one of PET, PI, BOPP, paper and PEEK. The material of the release layer is solvent silicone oil or solvent-free silicone oil. The material of the resin grid layer is high temperature resistant resin.

[0038] For example, the thickness of the substrate layer is 25 to 188 μm, and the thickness of the resin mesh layer is 15 to 100 μm.

[0039] In some embodiments, the depth of the groove convex strip 32 (that is, the depth of the grid structure 3) is 5-10 μm, and the width of the groove convex strip is 19-25 μm. Exemplarily, the depth of the groove convex strip can be 5 μm, 8 μm, and 10 μm. The width of the groove convex strip can be 19 μm, 22 μm, and 25 μm. Through research, we found that the exhaust and disappearance of the exhaust groove on the surface of the pressure-sensitive adhesive are a set of paradoxes, and the two are contradictory. If you want to ensure the exhaust of the exhaust groove, you need to increase the physical size of the exhaust groove (such as the depth of the exhaust groove and the width of the exhaust groove), but the increase in the physical size of the exhaust groove makes the disappearance of the exhaust groove difficult to increase by multiples, which means that the disappearance of the exhaust groove cannot be achieved. If you want to ensure the disappearance of the exhaust groove, you need to appropriately reduce the physical size of the exhaust groove, such as reducing the width of the exhaust groove and / or the depth of the exhaust groove, but the bubbles in the exhaust groove cannot be discharged smoothly. Therefore, it is necessary to find a balance between exhaust and disappearance to ensure that these two properties can be achieved at the same time. In addition, since most of the bubbles in the exhaust grooves gather at the exhaust nodes and are difficult to discharge, we have found through a large number of orthogonal experiments that, under the premise that the circumscribed circle diameter of the node structure of the grid release film is 15~30μm, when the depth of the pressed groove ridges on the grid release film is 5~10μm and the width of the pressed groove ridges is 19~25μm, the exhaust grooves transferred on the surface of the pressure-sensitive adhesive can be quickly discharged when the exhaust grooves are attached to the objects being attached, whether it is the bubbles in the exhaust groove channel or the bubbles in the exhaust nodes where the ends of the exhaust grooves meet, and the exhaust grooves are also guaranteed to disappear within the preset time.

[0040] For example, Figure 3As shown, the grooved convex strips 32 between adjacent hexagonal grids 31 intersect at the vertex position of the hexagon to form a node structure 33. In the present application, the node structure 33 formed by the intersection of adjacent grooved convex strips 32 can be arranged in any of the following ways, including but not limited to: Figure 3 As shown, the grooved convex strips 32 between three adjacent hexagonal grids 31 intersect at one of the vertex positions of the hexagonal grids to form a node structure 33, and the shape of the node structure is a triangle. Figure 5 When the size of the node structure is slightly smaller, near the intersection, the two sides of the groove convex strip 32 gradually shrink inward, and the shape of the two sides is generally an outward convex arc shape, so that the width of the groove convex strip gradually decreases, so that three adjacent groove convex strips 32 intersect to form a node structure 33.

[0041] Or, it can also be, Figure 6 As shown, when the size of the node structure 33 is slightly larger, near the intersection, the two side edges of the groove ridge 32 gradually expand outward, and the shape of the two side edges is generally an inwardly concave arc shape, so that the width of the groove ridge 32 gradually increases, so that three adjacent groove ridges 32 converge to form a node structure.

[0042] Or, it can also be, Figure 7 As shown, the width of the grooved convex strips 32 is constant. Adjacent grooved convex strips 32 meet to form a node structure 33.

[0043] In summary, the groove convex strip 32 is located near the node structure 33, and a transition section is formed between the groove convex strip 32 and the node structure 33. Towards the direction close to the node structure 33, the width of the transition section gradually decreases, or the width of the transition section gradually increases, or the width of the transition section remains unchanged.

[0044] The arrangement of the node structure formed by the intersection of the above-mentioned grooved convex strips needs to be adjusted accordingly according to the width of the grooved convex strips and the size of the node structure.

[0045] Since the resin grid layer is formed by embossing transfer with an anilox roller, a corresponding texture pattern can be engraved on the surface of the anilox roller in advance, and the structure and shape of the texture pattern correspond to the grid structure.

[0046] In some embodiments, the resin mesh layer 2 is configured to be able to remain unchanged at a temperature of at least 100° C., and the resin mesh layer is formed by photocuring of UV resin liquid.

[0047] Furthermore, the UV resin liquid includes the following raw materials in parts by weight: 100 parts of UV glue, 3-12 parts of UV crosslinking agent, and 3-4 parts of UV initiator; wherein the UV crosslinking agent is a mixture of one or more of a bifunctional UV crosslinking agent, a trifunctional UV crosslinking agent, and a tetrafunctional UV crosslinking agent. The amount of UV initiator added is 3%-4% of the amount of UV glue added.

[0048] For example, the UV glue may be epoxy UV glue, and the available models include but are not limited to: Loctite EA3335, TSBD2640, and Loctite 3523.

[0049] The UV initiator can initiate a polymerization reaction when the material is exposed to ultraviolet light. For example, the UV initiator is a mixture of one or more of 1-hydroxycyclohexyl phenyl ketone (PI-184), diphenyl-(2,4,6-trimethylbenzoyl)phosphine oxide (TPO), 2-isopropylthioxanthone, and isopropylthioxanthone (ITX105).

[0050] Bifunctional UV crosslinkers include, but are not limited to, polyethylene glycol 400 diacrylate (PEG400DA), 1,6-hexanediol diacrylate (HDDA, also known as "1,6-hexanediol diacrylate"), and polyurethane-modified diacrylate oligomer (DOUBLEMER® 5222).

[0051] Trifunctional UV crosslinkers include, but are not limited to, trimethylolpropane tris[3-(2-methylaziridinyl) propionate] (TTMAP), trimethylolpropane triacrylate (TMPTA), and pentaerythritol triacrylate (PETA).

[0052] Tetrafunctional UV crosslinkers include but are not limited to: Pentaerythritol tetraallyl ether, tetrafunctional polyester acrylate (ETERCURE 6325-100).

[0053] In this embodiment, the resin mesh layer is formed by UV resin liquid light curing, so that the resin mesh layer is resistant to high temperature (the temperature is maintained at 90-150°C without deformation, and even above 150°C without deformation). Therefore, when the adhesive is coated on the mesh release film and dried to form a pressure-sensitive adhesive, it can ensure that the entire mesh release film is not deformed, and the mesh structure is not deformed, thereby ensuring that the depth of the exhaust groove formed on the surface of the pressure-sensitive adhesive is consistent, and ensuring the exhaust stability and disappearance of the exhaust groove.

[0054] According to the second aspect of the present disclosure, the present invention also provides a method for preparing a mesh release film, the preparation method comprising glue dripping-embossing-UV primary curing-UV secondary curing-molding to obtain a mesh release film. The mesh release film comprises a substrate layer, a resin mesh layer and a release layer stacked in sequence from bottom to top, and the resin mesh layer has a mesh structure formed on the side in contact with the release layer.

[0055] The specific preparation method of the grid release film comprises: Step 1): UV resin liquid is transferred and coated onto the surface of the substrate layer by an anilox roller, and then UV initial curing is performed to initially form a resin grid layer with a grid structure on the surface of the substrate layer. The UV exposure during the UV initial curing is 500-2000 mj / cm 2 ; Step 2): The substrate layer with the resin grid layer formed on the surface is subjected to UV secondary curing molding; wherein the UV exposure during UV secondary curing is 500~2000 mj / cm 2 ; Step 3): A release agent is applied on the surface of the grid structure of the resin grid layer to form a release layer.

[0056] In this embodiment, the UV resin liquid includes the following raw materials in parts by weight: 100 parts of UV glue, 3-12 parts of UV crosslinking agent, and 3-4 parts of UV initiator; wherein the UV crosslinking agent is a mixture of one or more of a bifunctional UV crosslinking agent, a trifunctional UV crosslinking agent, and a tetrafunctional UV crosslinking agent.

[0057] Among them, in this embodiment, the UV resin liquid is added to the anilox roller, and the anilox roller transfers the UV resin liquid to the surface of the substrate layer in the form of embossing, and then UV primary curing is performed. After UV primary curing, a resin grid layer with a grid structure is formed on the surface of the substrate layer, and then further UV secondary curing is performed to form the resin grid layer on the surface of the substrate layer, further ensuring a stable connection between the resin grid layer and the substrate layer. It can be concluded that the materials of the resin grid layer and the grid structure formed on one side are not only the same, but they are also one-step, integrated light-cured and formed on the surface of the substrate layer. Then a release agent (such as silicone oil) is coated on the grid structure to form a release layer.

[0058] In this embodiment, the coating process is used, which has more advantages in controlling the size and appearance than the conventional laminating process. The UV curing embossing molding is faster and more thorough, and the depth and width data of the formed grid structure are more stable.

[0059] In a third aspect, the present disclosure further provides an adhesive tape, including the above-mentioned grid release film or the grid release film prepared by the above-mentioned method. The adhesive tape having the grid release film of the present application also has the following characteristics: under high temperature conditions, the grid release film can stably coat the pressure-sensitive adhesive to ensure that the formed pressure-sensitive adhesive is stable and does not deform. Moreover, when the pressure-sensitive adhesive is attached to the attached object, the exhaust grooves formed on the surface of the pressure-sensitive adhesive can quickly discharge the bubbles, and the exhaust grooves will disappear in a short time, without affecting the appearance and performance of the attached object.

[0060] Exemplarily, the adhesive tape includes a grid release film, a pressure-sensitive adhesive layer, a printed black film layer, a foam layer, an anti-stick coating layer and a copper foil tape layer which are sequentially stacked from bottom to top.

[0061] The present application is further described in detail below with reference to specific embodiments: Example 1 like Figure 1-Figure 3 As shown, a grid release film comprises a substrate layer 1, a resin grid layer 2 and a release layer 4 which are stacked in sequence from bottom to top, wherein the resin grid layer 2 is formed with a grid structure 3 on a side away from the substrate layer 1 (i.e., the resin grid layer 2 is formed with a grid structure 3 on a side in contact with the release layer 4); The grid structure 3 is composed of a plurality of uniformly arranged hexagonal grids 31 connected to each other, and groove convex strips 32 are formed between adjacent hexagonal grids. The groove convex strips 32 between adjacent hexagonal grids intersect at the vertex positions of the hexagonal grids to form a node structure 33. The shape of the node structure is a triangle, and the diameter of the circumscribed circle of the triangular node structure is 15-30 μm, the depth of the groove convex strips 32 is 5-10 μm, and the width of the groove convex strips 32 is 19-25 μm. Among them, the material of the substrate layer is PET, and the resin grid layer is formed by UV resin liquid photocuring. The UV resin liquid includes the following raw materials in parts by weight: 100 parts of UV glue, 10 parts of bifunctional UV cross-linking agent, and 3 parts of UV initiator. Among them, the bifunctional UV cross-linking agent is polyethylene glycol 400 diacrylate, and the UV initiator is 1-hydroxycyclohexyl phenyl ketone PI-184.

[0062] The specific preparation method of the grid release film comprises: Step 1): UV resin liquid is transferred and coated onto the surface of the substrate layer by an anilox roller, and then UV initial curing is performed to initially form a resin grid layer with a grid structure on the surface of the substrate layer. The UV exposure during the UV initial curing is 500mj / cm 2 ; Step 2): The substrate layer with the resin grid layer formed on the surface is subjected to UV secondary curing molding; wherein the UV exposure during UV secondary curing is 500 mj / cm 2 ; Step 3): A release agent is applied on the surface of the grid structure of the resin grid layer to form a release layer.

[0063] Example 2 This embodiment 2 is substantially the same as embodiment 1, except that the UV resin solution includes the following raw materials in parts by weight: 100 parts of UV glue, 6 parts of bifunctional UV crosslinking agent, 2 parts of trifunctional UV crosslinking agent, and 4 parts of UV initiator. The UV exposure during UV primary curing and UV secondary curing is 1000 mj / cm 2 The bifunctional UV crosslinker is 1,6-hexanediol diacrylate, the trifunctional UV crosslinker is trimethylolpropane triacrylate, and the UV initiator is diphenyl-(2,4,6-trimethylbenzoyl)phosphine oxide TPO.

[0064] Example 3 The present embodiment 3 is substantially the same as the embodiment 1, except that the UV resin solution comprises the following raw materials in parts by weight: 100 parts of UV glue, 5 parts of trifunctional UV crosslinking agent, and 3 parts of UV initiator. The UV exposure during UV primary curing and UV secondary curing is 1500 mj / cm 2 The trifunctional UV crosslinker is pentaerythritol triacrylate, and the UV initiator is isopropylthioxanthone ITX1105.

[0065] Example 4 This embodiment 4 is substantially the same as embodiment 1, except that the UV resin solution includes the following raw materials in parts by weight: 100 parts of UV glue, 3 parts of a tetrafunctional UV crosslinking agent, and 4 parts of a UV initiator. The UV exposure during the UV primary curing and UV secondary curing is 1000 mj / cm 2 The tetrafunctional UV crosslinker is pentaerythritol tetraallyl ether, and the UV initiator is 1-hydroxycyclohexyl phenyl ketone PI-184.

[0066] Example 5 This embodiment 5 is substantially the same as embodiment 1, except that the UV resin solution includes the following raw materials in parts by weight: 100 parts of UV glue, 5 parts of bifunctional UV crosslinking agent, 4 parts of trifunctional UV crosslinking agent, 3 parts of tetrafunctional UV crosslinking agent, and 3 parts of UV initiator. The UV exposure during UV primary curing and UV secondary curing is 2000 mj / cm 2 The bifunctional UV crosslinker is polyurethane modified diacrylate oligomer DOUBLEMER® 5222, the trifunctional UV crosslinker is pentaerythritol triacrylate, the tetrafunctional UV crosslinker is tetrafunctional polyester acrylate ETERCURE 6325-100, and the UV initiator is diphenyl-(2,4,6-trimethylbenzoyl)phosphine oxide TPO.

[0067] The components of the resin grid layer in the above embodiment are summarized in Table 2: Table 2 Composition of resin grid layer

[0068] Characterization and Testing: 1): The grid release film prepared in the above-mentioned embodiments 1-5 was subjected to a temperature resistance test, and the results are shown in Table 3 (determination of dimensional stability after high temperature baking): Table 3 Temperature resistance test results of various embodiments and comparative examples

[0069] The comparative example is a grid release film prepared by the existing lamination process, wherein the material of the grid layer of the grid release film is PE material.

[0070] It can be seen from Table 3 that the resin mesh layer and the entire mesh release film prepared by using the UV resin liquid of the present application can be resistant to high temperatures without deformation at 90-150°C, thereby ensuring that the exhaust effect of the exhaust grooves on the surface of the pressure-sensitive adhesive coated on the mesh release film is stable.

[0071] 2): Experiment on the correlation between the physical dimensions of the grooved convex strips of the grid structure of the grid release film and the air venting and disappearance properties of the pressure-sensitive adhesive.

[0072] Next, we further explore the correlation between the physical dimensions of the groove convex strips (such as depth and width) and the node structure dimensions on the air venting and vanishing properties of the air vents formed on the pressure-sensitive adhesive: taking the circumscribed circle diameter of the node structure, the depth of the groove convex strips and the width of the groove convex strips as variables, and other conditions being the same (such as the use of hexagonal grids, the same composition and thickness of the UV resin grid layer, the same substrate layer material, etc.), we explore the correlation between the physical dimensions of the groove convex strips and the air venting and vanishing properties of the air vents, that is, conduct an orthogonal correlation experiment (the table of influencing factors is shown in Table 4), and the results of the orthogonal experiment are shown in Table 5: Table 4 Influencing factors scheme table

[0073] Table 5 Orthogonal experiment results

[0074] Note: Both the exhaust effect and the disappearing effect need to be made into tape products for performance testing. This orthogonal experiment is conducted by making the same single-sided disappearing textured tape (at least including a grid release film, a pressure-sensitive adhesive and a substrate layer stacked from bottom to top) for comparative evaluation. The evaluation criteria are shown in Table 6 below: Table 6 Evaluation criteria for exhaust effect and vanishing effect of exhaust slots

[0075] Note: The mesh pattern in Table 6 refers to the grid-like exhaust grooves.

[0076] Among them, (1): Exhaust test: Cut the produced single-sided disappearing reticulated tape into a size of 50mm×50mm in an environment with a temperature of 23±2℃ and a humidity of 65±5%. Then stick the adhesive layer of the tape on the glass plate, and press the bubble in the middle of the tape clockwise with your finger to check its exhaust speed and whether it can be exhausted.

[0077] (2): Disappearance test: Cut the prepared single-sided disappearing patterned tape into a size of 50×50mm. Tear off the grid release film on the tape, and stick the grid adhesive surface flat on the white glass; use a 2kg rubber roller to roll back and forth 3 times (speed of 25mm / sec). Place the pasted sample at room temperature, use LED light and a magnifying glass to observe the disappearance of the pattern every 1hr, and record the disappearance time (observe all positions, and record the disappearance time after confirming that the pattern has completely disappeared).

[0078] Therefore, from the orthogonal experimental results - Table 5, we can conclude that: the depth (height) of the groove convex strip is 5-10um; the width of the groove convex strip is 19-25um; the node structure size formed by the intersection of the groove convex strips is less than 30um (that is, in the range of 15-30μm), which is the best range. Within this range, when the exhaust groove transferred to the surface of the pressure-sensitive adhesive is actually attached to the adhered object, the bubbles in the exhaust groove can be discharged and the exhaust groove can completely disappear.

[0079] More preferably, when the depth of the groove convex strip is 5μm, the width of the groove convex strip is 19μm, and the diameter of the circumscribed circle of the node structure is 25μm, the best exhaust effect and disappearance effect are achieved; or, when the depth of the groove convex strip is 8μm, the width of the groove convex strip is 25μm, and the diameter of the circumscribed circle of the node structure is 15μm, the best exhaust effect and disappearance effect are achieved; or, when the depth of the groove convex strip is 10μm, the width of the groove convex strip is 22μm, and the diameter of the circumscribed circle of the node structure is 15μm, the best exhaust effect and disappearance effect are achieved. Combined with the hexagonal grid and the UV resin grid layer, the prepared grid release film can have the characteristics of not deforming at high temperature, the bubbles in the exhaust groove transferred to the pressure-sensitive adhesive can be quickly discharged, and the disappearance effect can also be achieved.

[0080] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps recorded in this disclosure can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solutions disclosed in this disclosure can be achieved, and this document does not limit this.

[0081] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present disclosure, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0082] The above is only a specific embodiment of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any person skilled in the art who is familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present disclosure, which should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

1. A grid release film, comprising a substrate layer and a resin grid layer stacked in sequence from bottom to top, wherein the resin grid layer has a grid structure formed on a side away from the substrate layer; characterized in that: The grid structure is composed of a plurality of hexagonal grids connected to each other, and the grooved convex strips formed between adjacent hexagonal grids intersect at the vertex positions of the hexagonal grids to form a node structure, and the diameter of the circumscribed circle of the node structure is 15-30 μm.

2. The grid release film according to claim 1, characterized in that: The depth of the groove convex strip is 5-10 μm, and the width of the groove convex strip is 19-25 μm.

3. The grid release film according to claim 1, characterized in that: The resin mesh layer is configured to be able to remain unchanged at at least 100° C., and the resin mesh layer is formed by photocuring of UV resin liquid.

4. The grid release film according to claim 3, characterized in that: The UV resin liquid comprises the following raw materials in parts by weight: 100 parts of UV glue, 3-12 parts of UV crosslinking agent, and 3-4 parts of UV initiator; wherein the UV crosslinking agent is a mixture of one or more of a bifunctional UV crosslinking agent, a trifunctional UV crosslinking agent, and a tetrafunctional UV crosslinking agent.

5. The grid release film according to claim 4, characterized in that: The bifunctional UV crosslinking agent is a mixture of one or more of polyethylene glycol 400 diacrylate, 1,6-hexanediol diacrylate, and polyurethane modified diacrylate oligomer; The trifunctional UV crosslinking agent is a mixture of one or more of trimethylolpropane tris[3-(2-methylaziridinyl)propionate], trimethylolpropane triacrylate, and pentaerythritol triacrylate; The tetrafunctional UV crosslinking agent is a mixture of one or more of pentaerythritol tetraallyl ether and tetrafunctional polyester acrylate; The UV initiator is a mixture of one or more of 1-hydroxycyclohexyl phenyl ketone, diphenyl-(2,4,6-trimethylbenzoyl)phosphine oxide, 2-isopropylthioxanthone and isopropylthioxanthone.

6. The grid release film according to any one of claims 1 to 5, characterized in that: It also includes a release layer, which is stacked on the grid structure of the resin grid layer.

7. A method for preparing a grid release film, applied to the grid release film according to any one of claims 1 to 6, characterized in that: The preparation method comprises: The UV resin liquid is transferred and coated onto the surface of the substrate layer by an anilox roller, and then UV initial curing is performed to initially form a resin grid layer with a grid structure on the surface of the substrate layer. The UV exposure during the UV initial curing is 500-2000 mj / cm 2 ; The substrate layer with the resin grid layer formed on the surface is subjected to UV secondary curing molding; wherein the UV exposure during UV secondary curing is 500~2000 mj / cm 2 .

8. The preparation method according to claim 7, characterized in that: The UV resin liquid comprises the following raw materials in parts by weight: 100 parts of UV glue, 3-12 parts of UV crosslinking agent, and 3-4 parts of UV initiator; wherein the UV crosslinking agent is a mixture of one or more of a bifunctional UV crosslinking agent, a trifunctional UV crosslinking agent, and a tetrafunctional UV crosslinking agent.

9. The preparation method according to claim 7, characterized in that: The preparation method further comprises: coating a release agent on the surface of the grid structure of the resin grid layer to form a release layer.

10. An adhesive tape, characterized in that: The invention comprises the grid release film according to any one of claims 1 to 6 or the grid release film prepared by the method according to any one of claims 7 to 9.

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