Prime-coat-free net-shaped structure composite film and preparation process thereof
By adopting a basecoated mesh-like composite film with a multi-layer coextruded structure, the problem of insufficient adhesion of the existing composite film is solved, and good adhesion with thermoplastic materials is achieved, and the material usage is reduced.
Patent Information
- Application Number
- CN202411959706.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-26
- Publication Date
- 2025-05-30
AI Technical Summary
The existing composite films are not sticky enough when coated with thermoplastic materials such as EVA glue, resulting in a disengagement phenomenon, and a large amount of materials need to be coated to enhance the viscosity.
A primerless mesh-like composite film is used, which consists of a multi-layer coextruded structure, including an upper surface layer, a core layer and a lower surface layer. The lower surface layer is a mesh-like structure, and is prepared through specific component proportions and processes to form a film body with stronger viscosity.
The adhesive strength between the composite film and the thermoplastic material is improved, the use of thermoplastic material is reduced, and the separation problem caused by insufficient viscosity is avoided.
Smart Images
Figure CN120056551A_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to the technical field of composite films, and specifically, to a bottomless coating mesh structure composite film and a preparation process thereof. Background Art
[0002] In the later stage of coating thermoplastic materials such as EVA glue on existing composite films, the adhesion is often insufficient, resulting in detachment. In order to enhance the adhesion, a large amount of EVA glue often needs to be coated. Summary of the Invention
[0003] The purpose of the embodiments of the present disclosure is to provide a bottomless coating mesh structure composite film and a preparation process thereof to solve the above problems existing in the prior art.
[0004] To solve the above technical problems, on the one hand, an embodiment of the present disclosure provides a bottomless coating mesh structure composite film, including a film body. The film body is a multi-layer co-extrusion structure, which includes an upper surface layer, a core layer, and a lower surface layer. The upper surface layer, the core layer, and the lower surface layer form a multi-layer structure by co-extrusion. The lower surface layer is a mesh structure for bonding with thermoplastic materials.
[0005] In some embodiments, the upper surface layer is a polyolefin layer, and the upper surface layer includes the following components in parts by weight: 90-99 parts of random copolymerized polypropylene and 1-10 parts of anti-blocking masterbatch.
[0006] In some embodiments, the anti-blocking masterbatch includes siloxane and isotactic polypropylene. Among them, the mass of the siloxane accounts for 20-30% of the total mass of the anti-blocking masterbatch. The siloxane is in the form of siloxane particles, and the particle size of the siloxane particles is 1-2 μm.
[0007] In some embodiments, the upper surface layer is a matting masterbatch, and the matting masterbatch is a blend including 30 parts by weight of polypropylene and 70 parts by weight of polyethylene.
[0008] In some embodiments, the core layer is a polyolefin layer, and the core layer includes the following components in parts by weight: 90-99 parts of random copolymerized polypropylene and 1-10 parts of antistatic masterbatch.
[0009] In some embodiments, the antistatic masterbatch includes 75-85 parts by weight of isotactic homopolypropylene and 15-25 parts by weight of migrating antistatic agent.
[0010] In some embodiments, the migrating antistatic agent includes 50-60 parts by weight of polypropylene, 20-25 parts by weight of ethoxyamine, and 20-25 parts by weight of glycerol monostearate.
[0011] In some embodiments, the lower surface layer comprises components in the following parts by weight: 8-10 parts of linear low density polyethylene, 5-6.5 parts of ethylene-vinyl acetate copolymer, 1-2 parts of terpene resin, 0.8-1.5 parts of poly(propylene carbonate), 0.7-1.2 parts of branched polyethylene, and 1 part of anti-blocking masterbatch; wherein, the melt index of the poly(propylene carbonate) is 3-6 g / 10 min.
[0012] In some embodiments, the thickness of the film body is 15-20 μm, wherein the thickness of the upper surface layer 1 is 1-1.5 μm, the thickness of the core layer 2 is 12-17 μm, and the thickness of the lower surface layer 3 is 2-3 μm.
[0013] Another aspect of the embodiments of the present disclosure provides a preparation process of a bottom-coatless reticulated composite film, the bottom-coatless reticulated composite film being the bottom-coatless reticulated composite film described in any one of the above, and the preparation process comprising the following steps:
[0014] S1, Select raw materials, add a matting masterbatch or add random copolymer polypropylene and an anti-blocking masterbatch to form the upper surface layer; add random copolymer polypropylene and an antistatic masterbatch to form the core layer; add according to the formulation requirements of linear low density polyethylene, ethylene-vinyl acetate copolymer, terpene resin, poly(propylene carbonate), branched polyethylene, and anti-blocking masterbatch to form the lower surface layer;
[0015] S2, Extrusion operation, that is, extruding the prepared raw materials through an extruder to obtain a cast sheet;
[0016] S3, Stretching operation, that is, stretching the cast sheet obtained by the extrusion operation through a longitudinal stretching machine and a transverse stretching machine respectively to obtain a film;
[0017] S4, Rewinding operation, that is, trimming the edges of the film obtained after stretching and winding it into a tubular film roll;
[0018] S5, Slitting operation, placing the wound tubular film roll on an aging rack and then slitting it.
[0019] The embodiments of the present disclosure have a reticulated structure to have stronger adhesiveness, so as to facilitate adhesion to thermoplastic materials, and at the same time, it is also beneficial to reduce the use of thermoplastic materials. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings described below are only some embodiments recorded in the present disclosure. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.
[0021] Figure 1 This is a schematic structural diagram of the bottom - coat - free mesh - structured composite film in the embodiments of the present disclosure. Detailed implementation manners
[0022] Reference is made here to the accompanying drawings to describe various solutions and features of the present disclosure.
[0023] It should be understood that various modifications can be made to the embodiments applied herein. Therefore, the above - mentioned specification should not be regarded as a limitation, but merely as an example of the embodiments. Those skilled in the art will think of other modifications within the scope and spirit of the present disclosure.
[0024] The accompanying drawings, which are included in and form a part of this specification, illustrate embodiments of the present disclosure and, together with the general description of the present disclosure given above and the detailed description of the embodiments given below, serve to explain the principles of the present disclosure.
[0025] These and other features of the present disclosure will become apparent from the following description of the preferred forms of the embodiments, given by way of non - limiting example with reference to the accompanying drawings.
[0026] It should also be understood that although the present disclosure has been described with reference to some specific examples, those skilled in the art can surely implement many other equivalent forms of the present disclosure, which have the features as described in the claims and thus are all within the protection scope defined thereby.
[0027] When combined with the accompanying drawings, the above - mentioned and other aspects, features and advantages of the present disclosure will become more apparent in view of the following detailed description.
[0028] Hereinafter, specific embodiments of the present disclosure are described with reference to the accompanying drawings; however, it should be understood that the embodiments applied are merely examples of the present disclosure and can be implemented in various ways. Well - known and / or repetitive functions and structures are not described in detail to avoid obscuring the present disclosure with unnecessary or redundant details. Therefore, the specific structural and functional details applied herein are not intended to be limiting, but merely serve as a basis and representative basis for the claims to teach those skilled in the art to make any combination substantially.
[0029] The first embodiment of the present disclosure provides a bottom - coat - free mesh - structured composite film, which can be, for example, a biaxially oriented polypropylene film (BOPP), and it includes a film body, and the thickness of the film body here is 15 - 20 um. As Figure 1As shown, the film body is a multi-layer co-extrusion structure, which includes an upper surface layer 1, a core layer 2, and a lower surface layer 3. The upper surface layer 1, the core layer 2, and the lower surface layer 3 form a multi-layer structure by co-extrusion. Here, the lower surface layer 3 is used to bond with the thermoplastic material. Among them, the thermoplastic material is, for example, EVA adhesive 4, that is, a thermoplastic plastic copolymerized from ethylene and vinyl acetate.
[0030] Specifically, the upper surface layer 1 here is a polyolefin layer. In one embodiment, the upper surface layer 1 specifically includes the following components in parts by weight: 90-99 parts of random copolymerized polypropylene and 1-10 parts of anti-blocking masterbatch. The thickness of the upper surface layer 1 is 1-1.5 μm.
[0031] Further, the anti-blocking masterbatch includes siloxane and isotactic polypropylene. Among them, the mass of the siloxane accounts for 20-30% of the total mass of the anti-blocking masterbatch. Here, the siloxane is in the form of organic siloxane particles, and the particle size of the siloxane particles is 1-2 μm.
[0032] In another embodiment, the upper surface layer 1 is a matting masterbatch. Using the matting masterbatch makes the thickness of the upper surface layer 1 2-4 μm. Here, the matting masterbatch is a blend including 30 parts by weight of polypropylene and 70 parts by weight of polyethylene.
[0033] Further, the core layer 2 is a polyolefin layer. In one embodiment, the core layer 2 specifically includes the following components in parts by weight: 90-99 parts of random copolymerized polypropylene and 1-10 parts of antistatic masterbatch. Here, the thickness of the core layer 2 is 12-17 μm.
[0034] Specifically, the antistatic masterbatch includes 75-85 parts by weight of isotactic homopolypropylene and 15-25 parts by weight of migrating antistatic agent.
[0035] Further, the migrating antistatic agent includes 50-60 parts by weight of polypropylene, 20-25 parts by weight of ethoxyamine, and 20-25 parts by weight of glycerol monostearate.
[0036] Further, the lower surface layer 3 is a network structure, which is formed due to different crystallization rates between component substances. Due to the existence of the network structure, it has good adhesiveness after subsequent coating with EVA adhesive. Specifically, for the above composite film with a three-layer structure, the upper surface layer 1 and the core layer 2 are polyolefin layers, and the lower surface layer 3 is a functional layer. The network structure is formed through the functional layer. In this way, when coating EVA adhesive on the functional layer subsequently, due to the existence of the network structure, the bonding force between the functional layer and the glue is very good.
[0037] Further, the lower surface layer 3 comprises components in the following parts by weight: 8-10 parts of linear low density polyethylene (LLDPE), 5-6.5 parts of ethylene-vinyl acetate copolymer, 1-2 parts of terpene resin, 0.8-1.5 parts of poly(propylene carbonate), 0.7-1.2 parts of branched polyethylene, and 1 part of anti-blocking masterbatch; the thickness of the lower surface layer 3 here is 2-3 um. Among them, the melt index of the poly(propylene carbonate) is 3-6 g / 10 min.
[0038] Specifically, both the linear low density polyethylene and the ethylene-vinyl acetate copolymer in the lower surface layer 3 contain ethylene components, so they have good compatibility; in addition, after the composite film is cooled and crystallized after high-temperature melt extrusion, the linear low density polyethylene has a faster crystallization rate and a higher crystallization rate, and the ethylene-vinyl acetate copolymer has good filler inclusivity and crosslinking property, so that it can subsequently crystallize around the linear low density polyethylene to form a network structure. In this way, during the subsequent process of coating EVA glue in a high-temperature environment, the linear low density polyethylene in the functional layer melts and forms good crosslinking with the coating of the ethylene-vinyl acetate copolymer, thereby forming a composite film with a network structure.
[0039] In a specific embodiment, the bottom-coat-free network structure composite film comprises an upper surface layer 1, a core layer 2, and a lower surface layer 3. Among them, the upper surface layer 1 specifically comprises 99 parts of random copolymer polypropylene and 1 part of anti-blocking masterbatch; the core layer 2 specifically comprises components in the following parts by weight: 99 parts of random copolymer polypropylene and 1 part of antistatic masterbatch; the lower surface layer 3 comprises 10 parts of linear low density polyethylene (LLDPE), 5 parts of ethylene-vinyl acetate copolymer, 2 parts of terpene resin, 1 part of poly(propylene carbonate), 1 part of branched polyethylene, and 1 part of anti-blocking masterbatch.
[0040] The embodiment of the present disclosure has a network structure to have stronger adhesiveness, so as to facilitate adhesion with thermoplastic materials, and at the same time is beneficial to reducing the use of thermoplastic materials.
[0041] A preparation process of a bottom-coat-free network structure composite film according to a second embodiment of the present disclosure, where the bottom-coat-free network structure composite film is any one of the bottom-coat-free network structure composite films in the above first embodiment. The preparation process comprises the following steps:
[0042] S1, select raw materials, add a matting masterbatch or add random copolymer polypropylene and an anti-blocking masterbatch to form the upper surface layer 1; add random copolymer polypropylene and an antistatic masterbatch to form the core layer 2; add according to the formulation requirements of linear low density polyethylene, ethylene-vinyl acetate copolymer, terpene resin, poly(propylene carbonate), branched polyethylene, and anti-blocking masterbatch to form the lower surface layer 3;
[0043] Further, the above-mentioned various raw materials are accurately proportioned by PCL according to the set process ratio. After passing through a vibrator, the materials enter the mixing hopper through different inlets. The various materials in the mixing hopper can be evenly mixed under the action of a stirrer to form raw materials.
[0044] Specifically, for example, adding 100 parts of matting masterbatch, or adding 99 parts of random copolymer polypropylene and 1 part of anti-blocking masterbatch to form the upper surface layer 1; adding 99 parts of random copolymer polypropylene and 1 part of antistatic masterbatch to form the core layer 2; adding according to the proportioning requirements of 10 parts of linear low-density polyethylene (LLDPE), 5 parts of ethylene-vinyl acetate copolymer, 2 parts of terpene resin, 1 part of polycarbonate propylene ester, 1 part of branched polyethylene, and 1 part of anti-blocking masterbatch to form the lower surface layer 3;
[0045] S2, extrusion operation, that is, the prepared raw materials are melt-extruded through an extruder to obtain a cast sheet;
[0046] S3, stretching operation, that is, the cast sheet obtained through the extrusion operation is stretched through a longitudinal stretching machine and a transverse stretching machine respectively to obtain a film;
[0047] S4, winding operation, that is, the film obtained after stretching is trimmed to form a cylindrical film roll;
[0048] S5, slitting operation, the cylindrical film roll obtained by winding is placed on an aging rack for 24 - 72 h and then slit.
[0049] Table 1 and Table 2 below respectively show the peel strength and paper covering force value data of the bottomless coated reticulated composite film with a reticulated structure and the ordinary pre-coated film substrate after being coated with EVA glue. It can be clearly seen from Table 1 and Table 2 below that the bottomless coated reticulated composite film with a reticulated structure has stronger adhesion.
[0050] Table 1
[0051]
[0052] Table 2
[0053]
[0054] Table 3 below shows the comparison of the peel strength performance between the bottomless coated reticulated composite film with a reticulated structure and the ordinary bottomless pre-coated film after EVA paper covering. It is not difficult to find from Table 3 below that the peel strength of the composite film with a reticulated structure is greater when coated with the same thickness of EVA glue. That is to say, in order to achieve the same peel strength as the existing composite film, the composite film with a reticulated structure can reduce the thickness of the EVA coating layer.
[0055] Table 3
[0056]
[0057] Embodiments of the present disclosure have a mesh structure to have stronger adhesiveness, thereby facilitating adhesion to thermoplastic materials and also helping to reduce the use of thermoplastic materials.
[0058] In addition, the features of the embodiments shown in the drawings of the present application or various embodiments mentioned in this specification do not have to be understood as independent embodiments of each other. Instead, each feature described in one example of an embodiment can be combined with one or more other desired features from other embodiments to produce other embodiments not described in words or with reference to the drawings.
[0059] The above-described embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.
Claims
1. A non-priming network structure composite film, characterized in that: It includes a film body, which is a multi-layer co-extruded structure, including an upper surface layer, a core layer and a lower surface layer. The upper surface layer, the core layer and the lower surface layer are formed into a multi-layer structure by co-extrusion, and the lower surface layer is a mesh structure for bonding with thermoplastic materials.
2. The primer-free network structure composite film according to claim 1, characterized in that: The upper surface layer is a polyolefin layer, and the upper surface layer comprises the following components in the following weight proportions: 90 to 99 parts of random copolymer polypropylene and 1 to 10 parts of anti-blocking masterbatch.
3. The primer-free network structure composite film according to claim 2, characterized in that: The anti-adhesion masterbatch comprises siloxane and isotactic polypropylene, wherein the mass of the siloxane accounts for 20-30% of the total mass of the anti-adhesion masterbatch, and the siloxane is in the form of siloxane particles, and the particle size of the siloxane particles is 1-2 μm.
4. The primer-free network structure composite film according to claim 1, characterized in that: The upper surface layer is a matte masterbatch, and the matte masterbatch is a blend including 30 parts by weight of polypropylene and 70 parts by weight of polyethylene.
5. The primer-free network structure composite film according to claim 1, characterized in that: The core layer is a polyolefin layer, and the core layer comprises the following components in the following weight proportions: 90 to 99 parts of random copolymer polypropylene and 1 to 10 parts of antistatic masterbatch.
6. The primer-free network structure composite film according to claim 5, characterized in that: The antistatic masterbatch comprises 75 to 85 parts by weight of isotactic homopolypropylene and 15 to 25 parts by weight of a migratory antistatic agent.
7. The primer-free network structure composite film according to claim 6, characterized in that: The migratory antistatic agent comprises 50 to 60 parts by weight of polypropylene, 20 to 25 parts by weight of ethoxylated amine and 20 to 25 parts by weight of glycerol monostearate.
8. The primer-free network structure composite film according to claim 1, characterized in that: The lower surface layer includes the following components in proportion by weight: 8 to 10 parts of linear low-density polyethylene, 5 to 6.5 parts of ethylene-vinyl acetate copolymer, 1 to 2 parts of terpene resin, 0.8 to 1.5 parts of polycarbonate propylene, 0.7 to 1.2 parts of branched polyethylene, and 1 part of anti-blocking masterbatch; wherein the melt index of the polycarbonate propylene is 3-6 g / 10 min.
9. The primer-free network structure composite film according to claim 1, characterized in that: The thickness of the membrane body is 15-20 um, wherein the thickness of the upper surface layer 1 is 1-1.5 um, the thickness of the core layer 2 is 12-17 um, and the thickness of the lower surface layer 3 is 2-3 um.
10. A process for preparing a composite film with a non-priming network structure, characterized in that: The non-primer-coated network structure composite film is the non-primer-coated network structure composite film according to any one of claims 1 to 9, and the preparation process The following steps are involved: S1, selecting raw materials, adding matte masterbatch or adding random copolymer polypropylene and anti-blocking masterbatch to form an upper surface layer; adding random copolymer polypropylene and antistatic masterbatch to form a core layer; adding linear low-density polyethylene, ethylene-vinyl acetate copolymer, terpene resin, polycarbonate propylene, branched polyethylene, and anti-blocking masterbatch according to the ingredient requirements to form a lower surface layer; S2, extrusion operation, that is, the prepared raw materials are melted and extruded through an extruder to obtain a casting sheet; S3, stretching operation, that is, the cast sheet obtained by the extrusion operation is stretched by a longitudinal stretching machine and a transverse stretching machine respectively, so as to obtain a film; S4, a winding operation, that is, the film obtained after stretching is trimmed to form a cylindrical film roll; S5, slitting operation, placing the rolled cylindrical film roll on the aging rack and then slitting it.