Antistatic film and preparation method thereof

Abstract

The invention discloses an antistatic film and a preparation method thereof, belonging to the technical field of antistatic film. The antistatic film comprises a base film, at least one side of which is co-extruded with a carrier film; the porosity of the carrier film is greater than the porosity of the base film by 20-80%; an antistatic coating is provided on the carrier film by online roller coating; the antistatic coating comprises 15-20 parts of an antistatic base material, and the antistatic base material comprises the following component proportions: 1-2 parts of graphene oxide, 0.5-1 parts of ferrocene and 5-8 parts of antimony-doped tin dioxide; 20-25 parts of an adhesive; 0.1-0.2 parts of a wetting agent; 1-2 parts of a cross-linking agent; 80-150 parts of deionized water; 1.5-2 parts of a silicon dioxide dispersion emulsion; the antistatic film and the preparation method thereof of the invention have strong adhesion of the prepared antistatic film coating, good consistency of surface resistance in each area of ​​the film, and can ensure a good light transmission effect.

Description

Technical Field

[0001] The invention specifically relates to an antistatic film and a preparation method thereof, and belongs to the technical field of antistatic films. Background Art

[0002] During the transportation or use of products such as glass, various material plates, and electronic products, the surface is easily contaminated or scratched by contact, so plastic film is used to cover the surface to avoid contamination or damage; since the dielectric constant of plastic film is small, it is a non-conductor with high insulation performance, so it will generate static electricity; and the static electricity charge accumulates on the surface of the plastic film, which is easy to cause dust adsorption on the surface, and even cause discharge, causing fire; in order to avoid the accumulation of static electricity on the surface of the plastic film, the plastic film will be treated with antistatic treatment to increase its conductive performance; existing antistatic films, such as Chinese patent publication number: CN119017811A, disclose a composite antistatic film and its preparation method, the composite antistatic film includes a core layer and an outer layer, the core layer is made of toughened modified PET resin, and the outer layer is made of antistatic PET resin The composite antistatic film of this structure has antistatic properties, can improve the molding efficiency of the composite antistatic film, can also promote the rapid discharge of static electricity, and improve the dustproofness of the composite antistatic film; for example, China Patent Authorization Announcement No.: CN115109294B discloses an antistatic film and a preparation method thereof, wherein the carbon nanotube dispersion, aqueous adhesive resin, olefin emulsion, water and additives are evenly mixed to obtain a carbon nanotube antistatic coating liquid; the antistatic film prepared by this method obtains a more superior light transmittance while ensuring excellent conductivity, achieving a combination of high light transmittance and high conductivity, but when the above-mentioned antistatic film is coated, due to the compatibility problem between the additive and the resin, the additive cannot be fully dispersed, resulting in large deviations in the antistatic performance of various regions of the film, and the overall adhesion is general and the peeling resistance is poor. Summary of the invention

[0003] To solve the above problems, the present invention proposes an antistatic film and a preparation method thereof. The prepared antistatic film coating has strong adhesion, good surface resistance consistency in various regions of the film, and can ensure good light transmission effect.

[0004] The antistatic film of the present invention comprises a base film, at least one side of which is co-extruded with a carrier film; the porosity of the carrier film is greater than that of the base film by 20-80%; an antistatic coating is provided on the carrier film by online roller coating; the carrier film and the base film can be co-extruded into one body, and a large ratio of pores is formed on the surface of the carrier film, so that a carrier skeleton of the antistatic coating is formed on the surface of the base film, that is, a multi-dimensional spatial network structure is formed on the surface of the base film, so that the antistatic coating can be closely combined with the base film; the antistatic coating is fully coated on the surface of the base film to ensure the overall antistatic ability and the anti-peeling ability of the antistatic coating; the antistatic coating comprises:

[0005] 15-20 parts of an antistatic base material, wherein the antistatic base material comprises the following component proportions: 1-2 parts of graphene oxide, 0.5-1 parts of ferrocene and 5-8 parts of antimony-doped tin dioxide; a conductive system is formed on the surface of the base film by the antistatic base material, wherein the antistatic base material uses a small amount of graphene oxide as a network skeleton of the conductive system, and uses a large proportion of antimony-doped tin dioxide as a filler between the network skeletons to form a composite coating, that is, graphene oxide with high conductivity is used as the network skeleton, conductive nodes are formed around the antimony-doped tin dioxide, and conductive nodes are formed by approaching the metal conductive Antimony-doped tin dioxide with high conductivity is used to form a conductive filling surface, and because antimony-doped tin dioxide has high light transmittance in the visible light range, the antistatic coating has excellent conductive properties while maintaining the basic light transmittance of the base film. In addition, by combining graphene oxide and ferrocene, that is, by combining ferrocene molecules with functional groups on the surface of graphene oxide, ferrocene groups are introduced into graphene. Graphene oxide is modified with highly uniformly dispersed ferrocene, so that graphene oxide can be fully dispersed in the adhesive, thereby ensuring the consistency of the antistatic effect of the antistatic coating.

[0006] Adhesive 20~25 parts;

[0007] Wetting agent 0.1~0.2 parts;

[0008] 1~2 parts of cross-linking agent;

[0009] 80~150 parts of deionized water;

[0010] 1.5~2 parts of silicon dioxide dispersion emulsion.

[0011] Furthermore, the raw materials of the carrier film include a basic component with the same proportion as the raw materials of the base film, and also include an inorganic material, and the amount of the inorganic material added is 0.5~2% of the total amount of the basic component; the inorganic material includes nano-scale calcium carbonate and silicon dioxide, and the ratio of calcium carbonate to silicon dioxide is 1:1~2; the nano-scale calcium carbonate and silicon dioxide of the inorganic material are fully mixed in advance, and after being mixed into the inorganic material basic component and fully dispersed, the inorganic material can be fully dispersed in the basic component, and the silicon dioxide in the inorganic material can promote the dispersion effect of calcium carbonate; when the carrier film is in a high-multiple stretching film forming process, due to the action of calcium carbonate, a uniform pore array will be generated on the surface of the carrier film, and because the stretching process is in a heated state, the antistatic coating coated on the surface of the carrier film enters the pore array, and after curing and shaping, the adhesive forms a three-dimensional coating and bonding with the base film, which can form a tight structure of the antistatic coating on the surface of the base film, and can ensure the adhesion of the antistatic coating, thereby forming a dense and uniform antistatic layer on the surface of the base film.

[0012] Furthermore, the base film is a PE film; and the adhesive is a polyurethane adhesive emulsion.

[0013] Furthermore, the thickness ratio of the base film to the carrier film is 1:0.1~1.

[0014] Furthermore, the antistatic base material is 18 parts, and the antistatic base material includes the following component ratios: 2 parts of graphene oxide, 1 part of ferrocene and 7 parts of antimony-doped tin dioxide; 25 parts of adhesive; 0.2 parts of wetting agent; 2 parts of cross-linking agent; 100 parts of deionized water; and 2 parts of silica dispersion emulsion.

[0015] A method for preparing an antistatic film, which is used to prepare an antistatic film, is specifically as follows:

[0016] The first step is to prepare the film carrier raw material, and fully disperse the basic components of the film carrier and the inorganic material to obtain the film carrier raw material;

[0017] The second step is to prepare the antistatic coating. The graphene oxide, ferrocene and 30 parts of deionized water are put into a ball mill for grinding for 30±5 min. The mixture is allowed to stand for 30±5 min. Then, all the remaining raw materials of the antistatic coating are put into the ball mill for grinding again for 4±0.5 h. The antistatic coating liquid is obtained.

[0018] The third step is melt extrusion, where the carrier film raw material and the base film raw material are fed into their respective extruders, and then enter the double-channel die head through a melt metering pump and a melt filter, and a composite film is obtained by co-extrusion;

[0019] The fourth step is online roller coating, feeding the antistatic coating liquid into a blade coater, and passing the composite film through the blade coater, and the blade coater coats the composite film with the antistatic coating liquid to obtain a coating film;

[0020] The fifth step is to form the antistatic film. The coated film is sent to a tentering machine for biaxial stretching. After the stretching is completed, it is heat-set to obtain an antistatic film.

[0021] Furthermore, when the tenter machine is stretched, longitudinal stretching is first performed, and it is preheated to 85±2°C; and longitudinal stretching is performed 3 times, and then transverse stretching is performed. When stretching, it is preheated to 95±2°C and transverse stretching is performed, and the stretching ratio is 3±1; the heat setting temperature is 230±10°C.

[0022] Compared with the prior art, the antistatic film and preparation method thereof of the present invention adopts a combination of graphene oxide and antimony-doped tin dioxide, so that the antistatic coating has excellent conductive properties while maintaining the basic light transmittance of the base film; and by modifying the graphene oxide with ferrocene molecules, the graphene oxide can be fully dispersed in the antistatic coating, and the carrier film is used as the skeleton of the antistatic coating, so that the antistatic coating can be fully and comprehensively attached to the surface of the skeleton, the overall anti-stripping ability is good, the surface resistance of each area of ​​the film is consistent, and a good light transmittance effect can be guaranteed. DETAILED DESCRIPTION

[0023] The antistatic film of the present invention comprises a base film, at least one side of which is co-extruded with a carrier film; the porosity of the carrier film is greater than that of the base film by 20-80%; an antistatic coating is provided on the carrier film by online roller coating; the carrier film and the base film can be co-extruded into one body, and a large ratio of pores is formed on the surface of the carrier film, so that a carrier skeleton of the antistatic coating is formed on the surface of the base film, that is, a multi-dimensional spatial network structure is formed on the surface of the base film, so that the antistatic coating can be closely combined with the base film; the antistatic coating is fully coated on the surface of the base film to ensure the overall antistatic ability and the anti-peeling ability of the antistatic coating; the antistatic coating comprises:

[0024] 15-20 parts of an antistatic base material, wherein the antistatic base material comprises the following component proportions: 1-2 parts of graphene oxide, 0.5-1 parts of ferrocene and 5-8 parts of antimony-doped tin dioxide; a conductive system is formed on the surface of the base film by the antistatic base material, wherein the antistatic base material uses a small amount of graphene oxide as a network skeleton of the conductive system, and uses a large proportion of antimony-doped tin dioxide as a filler between the network skeletons to form a composite coating, that is, graphene oxide with high conductivity is used as the network skeleton, conductive nodes are formed around the antimony-doped tin dioxide, and conductive nodes are formed by approaching the metal conductive Antimony-doped tin dioxide with high conductivity is used to form a conductive filling surface, and because antimony-doped tin dioxide has high light transmittance in the visible light range, the antistatic coating has excellent conductive properties while maintaining the basic light transmittance of the base film. In addition, by combining graphene oxide and ferrocene, that is, by combining ferrocene molecules with functional groups on the surface of graphene oxide, ferrocene groups are introduced into graphene. Graphene oxide is modified with highly uniformly dispersed ferrocene, so that graphene oxide can be fully dispersed in the adhesive, thereby ensuring the consistency of the antistatic effect of the antistatic coating.

[0025] Adhesive 20~25 parts;

[0026] Wetting agent 0.1~0.2 parts;

[0027] 1~2 parts of cross-linking agent;

[0028] 80~150 parts of deionized water;

[0029] 1.5~2 parts of silicon dioxide dispersion emulsion.

[0030] The raw materials of the carrier film include a basic component with the same proportion as the raw materials of the base film, and also include an inorganic material, and the amount of the inorganic material added is 0.5-2% of the total amount of the basic component; the inorganic material includes nano-scale calcium carbonate and silicon dioxide, and the ratio of calcium carbonate to silicon dioxide is 1:1-2; the nano-scale calcium carbonate and silicon dioxide of the inorganic material are fully mixed in advance, and after being mixed into the inorganic material basic component and fully dispersed, the inorganic material can be fully dispersed in the basic component, and the silicon dioxide in the inorganic material can promote the dispersion effect of calcium carbonate; when the carrier film is in the high-multiple stretching film forming process, due to the effect of calcium carbonate, a uniform pore array will be generated on the surface of the carrier film, and because the stretching process is in a heated state, the antistatic coating coated on the surface of the carrier film enters the pore array, and after curing and shaping, the adhesive forms a three-dimensional coating and bonding with the base film, which can form a tight structure of the antistatic coating on the surface of the base film, and can ensure the adhesion of the antistatic coating, thereby forming a dense and uniform antistatic layer on the surface of the base film.

[0031] The base film is a PE film; the adhesive is a polyurethane adhesive emulsion.

[0032] The thickness ratio of the base film to the carrier film is 1:0.1~1.

[0033] A method for preparing an antistatic film, which is used to prepare an antistatic film, is specifically as follows:

[0034] The first step is to prepare the film carrier raw material, and fully disperse the basic components of the film carrier and the inorganic material to obtain the film carrier raw material;

[0035] The second step is to prepare the antistatic coating. The graphene oxide, ferrocene and 30 parts of deionized water are put into a ball mill for grinding for 30±5 min. The mixture is allowed to stand for 30±5 min. Then, all the remaining raw materials of the antistatic coating are put into the ball mill for grinding again for 4±0.5 h. The antistatic coating liquid is obtained.

[0036] The third step is melt extrusion, where the carrier film raw material and the base film raw material are fed into their respective extruders, and then enter the double-channel die head through a melt metering pump and a melt filter, and a composite film is obtained by co-extrusion;

[0037] The fourth step is online roller coating, feeding the antistatic coating liquid into a blade coater, and passing the composite film through the blade coater, and the blade coater coats the composite film with the antistatic coating liquid to obtain a coating film;

[0038] The fifth step is to form the antistatic film. The coated film is sent to a tentering machine for biaxial stretching. After the stretching is completed, it is heat-set to obtain an antistatic film.

[0039] When the tenter machine is stretched, longitudinal stretching is performed first, and it is preheated to 85±2°C; and longitudinal stretching is performed 3 times, and then transverse stretching is performed. When stretching, it is preheated to 95±2°C and transverse stretching is performed, and the stretching ratio is 3±1; the heat setting temperature is 230±10°C.

[0040] The diaphragms of the embodiments and comparative examples were prepared in the following process:

[0041] First, prepare a comparative example membrane:

[0042] Comparative Example 1: First, a base film is directly prepared according to the base film ingredients of the present application, and the base film thickness is 50 μm; and the prepared base film is cut into pieces to obtain a first film sheet;

[0043] Comparative Example 2: The first film is coated with a commercial antistatic liquid (GW-2009 from Boyuan Chemical Industry), and dried and cured to obtain a second film;

[0044] Comparative Example 3: A composite film is prepared according to the first to third steps of the antistatic film preparation method of the present invention, and the composite film is cut into pieces to obtain a film sheet, and the thickness ratio of the base film to the carrier film is 1:0.3; then, a commercial antistatic liquid (Boyuan Chemical GW-2009) is coated on the carrier film surface of the film sheet, and dried and cured to obtain a third film sheet;

[0045] Next, prepare the film of the embodiment: First, prepare the antistatic coating according to the second step of the antistatic film preparation method of the present invention, wherein the grinding time of the antistatic coating is within the fluctuation value range and has no effect on the result. The components selected for the antistatic coating of the antistatic film of the present invention are as follows:

[0046] Graphene oxide Nanjing Xianfeng Nanomaterial Technology Co., Ltd.;

[0047] Ferrocene Sigma Reagent Company, USA;

[0048] National Ultrafine Powder Engineering Research Center of Antimony-Doped Tin Dioxide;

[0049] Adhesives DSM (NeoRozR-620);

[0050] Wetting agent Sangda Chemical Co., Ltd. (TFE-2);

[0051] Cross-linking agent Dongwan Xuyihua Chemical Co., Ltd. (XH-540);

[0052] Silicon dioxide dispersion emulsion Shanghai EFUSI Industrial Co., Ltd. (EFUSI-Y01);

[0053] Deionized water.

[0054] The composition ratio of the antistatic coating of the present invention is shown in Table 1:

[0055]

[0056] Embodiment 1 to Embodiment 6: The present invention prepares 6 groups of antistatic coatings according to the above-mentioned matching groups A to F, and then prepares antistatic film sheets according to the antistatic film preparation method of the present invention; wherein the antistatic coating of Embodiment 1 adopts matching group A, and the antistatic coating of Embodiment 2 adopts matching group B, so that the matching groups of the embodiments and the antistatic coatings correspond one to one; and the preparation methods of Embodiment 1 to Embodiment 6 are completely consistent;

[0057] Next, performance tests were performed on Examples 1 to 6, and Comparative Examples 1 and 2, and the test methods were as follows: the thickness test was performed using GB / T33399; the surface resistance was tested using GB / T33398; the adhesion was tested using GB / T9286 (hundred-grid test method); the transmittance test was tested using GB / T2410; the tensile strength was tested using GB / T25255; the test results are shown in Table 2;

[0058]

[0059] It can be seen from the above test that the light transmittance reduction of the antistatic film prepared in Examples 1 to 6 is relatively low, and only decreased by 2.7% to 3.4% compared with the sample without antistatic coating (Comparative Example 1); and the surface resistance of the samples coated with antistatic coating (Implementation 1 to Example 6) is greatly reduced, and the surface resistance improvement effect is also more obvious compared with the antistatic liquid on the market (Comparative Example 2 and Comparative Example 3); the surface resistance of the existing antistatic liquid on the market is 9th power, while the surface resistance of Implementation 1 to Example 6 is 6th power; the impedance is significantly reduced, and the adhesion grade of Implementation 1 to Example 6 of the present application is 5B grade (the hundred grid test method is divided into 0B~ 5B, 5B is the highest and has the strongest adhesion); wherein, relative to Examples 1 to 6, Comparative Example 2 is a 50 μm base film, and has poor overall adhesion and anti-peeling capabilities, and the difference between Comparative Example 2 and Comparative Example 3 is that Comparative Example 2 is only a 50 μm base film, and Comparative Example 3 uses the composite film prepared by Examples 1 to 6; thereby, the adhesion can be improved by two levels; relative to Examples 1 to 6, Comparative Example 3 uses the antistatic liquid on the market to coat the film, and Examples 1 to 6 use the antistatic coating to coat the film; thus, it can be seen that the antistatic coating of Examples 1 to 6 has better anti-peeling effect.

[0060] The above embodiments are only preferred implementations of the present invention, so any equivalent changes or modifications made according to the structures, features and principles described in the scope of application of the present invention are included in the scope of application of the present invention.

Claims

1. An antistatic film, characterized in that: The invention comprises a base film, wherein at least one side of the base film is co-extruded with a carrier film; the porosity of the carrier film is 20-80% greater than the porosity of the base film; an antistatic coating is provided on the carrier film by online roller coating; the antistatic coating comprises: 15~20 parts of antistatic base material, The antistatic base material comprises the following components in a proportion: 1-2 parts of graphene oxide, 0.5-1 parts of ferrocene and 5-8 parts of antimony-doped tin dioxide; Adhesive 20~25 parts; Wetting agent 0.1~0.2 parts; 1~2 parts of cross-linking agent; 80~150 parts of deionized water; 1.5-2 parts of silicon dioxide dispersion emulsion; The raw materials of the carrier film include basic components with the same proportion as the base film raw materials, and also include inorganic materials, and the addition amount of the inorganic materials is 0.5-2% of the total amount of the basic components; the inorganic materials include nano-scale calcium carbonate and silicon dioxide, and the ratio of calcium carbonate to silicon dioxide is 1:1-2.

2. The antistatic film according to claim 1, characterized in that: The base film is a PE film; the adhesive is a polyurethane adhesive emulsion.

3. The antistatic film according to claim 1, characterized in that: The thickness ratio of the base film to the carrier film is 1:0.1~1.

4. The antistatic film according to claim 1, characterized in that: The antistatic base material is 18 parts, and the antistatic base material includes the following component proportions: 2 parts of graphene oxide, 1 part of ferrocene and 7 parts of antimony-doped tin dioxide; 25 parts of adhesive; 0.2 parts of wetting agent; 2 parts of crosslinking agent; 100 parts of deionized water; and 2 parts of silicon dioxide dispersion emulsion.

5. A method for preparing an antistatic film, for preparing the antistatic film according to any one of claims 1 to 4, characterized in that: The method is specifically as follows: The first step is to prepare the film carrier raw material, and fully disperse the basic components of the film carrier and the inorganic material to obtain the film carrier raw material; The second step is to prepare the antistatic coating. The graphene oxide, ferrocene and 30 parts of deionized water are put into a ball mill for grinding for 30±5 min. The mixture is allowed to stand for 30±5 min. Then, all the remaining raw materials of the antistatic coating are put into the ball mill for grinding again for 4±0.5 h. The antistatic coating liquid is obtained. The third step is melt extrusion, where the carrier film raw material and the base film raw material are fed into their respective extruders, and then enter the double-channel die head through a melt metering pump and a melt filter, and a composite film is obtained by co-extrusion; The fourth step is online roller coating, feeding the antistatic coating liquid into a blade coater, and passing the composite film through the blade coater, and the blade coater coats the composite film with the antistatic coating liquid to obtain a coating film; The fifth step is to form the antistatic film. The coated film is sent to a tentering machine for biaxial stretching. After the stretching is completed, it is heat-set to obtain an antistatic film.

6. The method for preparing an antistatic film according to claim 5, characterized in that: When the tenter machine is stretched, longitudinal stretching is performed first, and it is preheated to 85±2°C; and longitudinal stretching is performed 3 times, and then transverse stretching is performed. When stretching, it is preheated to 95±2°C and transverse stretching is performed, and the stretching ratio is 3±1; the heat setting temperature is 230±10°C.

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