阅读说明：本技术 一种高阻隔复合膜及其制备方法和应用 (High-barrier composite film and preparation method and application thereof ) 是由 闫银凤 高可 王宏磊 沙连峰 李华帅 李胜国 周宏涛 李丽丽 于 2020-08-13 设计创作，主要内容包括：本发明公开了一种高阻隔复合膜,包括耐高温承印层和耐阻隔基层；耐高温承印层为双向拉伸聚乙烯膜层,其外表面涂布PTFE涂层、内表面为油墨印刷层；耐阻隔基层为低密度聚乙烯膜层,其表面涂布PVA涂层；耐高温承印层的内表面与耐阻隔基层的PVA涂层之间通过双组分无溶剂聚氨酯胶黏剂层粘结。本发明还公开了高阻隔复合膜制备方法和其在制包装袋中的应用。本发明的方法所制高阻隔复合膜,其耐高温承印层为外表面涂布PTFE涂层的双向拉伸聚乙烯膜层,其耐阻隔基层为表面涂布PVA涂层低密度聚乙烯膜层,两层相同材料即聚乙烯材料,利于材料循环使用,且耐高温性和阻隔性好,制袋时热压温度可达200℃,所制包装袋封边平整,无虚封、无受热收缩、折皱现象。(The invention discloses a high-barrier composite film, which comprises a high-temperature-resistant printing layer and a barrier-resistant base layer; the high-temperature resistant printing layer is a biaxially oriented polyethylene film layer, the outer surface of the high-temperature resistant printing layer is coated with a PTFE coating, and the inner surface of the high-temperature resistant printing layer is an ink printing layer; the barrier resistant base layer is a low-density polyethylene film layer, and the surface of the barrier resistant base layer is coated with a PVA coating; the inner surface of the high-temperature resistant printing layer is bonded with the PVA coating of the barrier-resistant base layer through a double-component solvent-free polyurethane adhesive layer. The invention also discloses a preparation method of the high-barrier composite film and application of the high-barrier composite film in packaging bags. The high-temperature-resistant printing layer of the high-barrier composite film prepared by the method is a biaxially oriented polyethylene film layer coated with a PTFE coating on the outer surface, the barrier-resistant base layer of the high-temperature-resistant composite film is a low-density polyethylene film layer coated with a PVA coating on the surface, two layers of the same material, namely polyethylene material, are beneficial to recycling of the material, and have good high temperature resistance and barrier property, the hot pressing temperature can reach 200 ℃ during bag making, and the prepared packaging bag has smooth edge sealing and no phenomena of virtual sealing, thermal shrinkage and wrinkling.)

1. A high-barrier composite film is characterized by comprising a high-temperature-resistant printing layer and a barrier-resistant base layer; the high-temperature-resistant printing layer is a biaxially oriented polyethylene film layer, the outer surface of the high-temperature-resistant printing layer is coated with a PTFE coating, and the inner surface of the high-temperature-resistant printing layer is an ink printing layer; the barrier resistant base layer is a low-density polyethylene film layer, and a PVA coating is coated on the surface of the barrier resistant base layer; the inner surface of the high-temperature resistant printing layer is bonded with the PVA coating of the barrier-resistant base layer through a bi-component solvent-free polyurethane adhesive layer.

2. The high barrier composite membrane according to claim 1, wherein the PTFE coating has a dry coating weight of 2.0 to 2.5g/m²。

3. The high barrier composite film according to claim 1, wherein the PVA coating has a dry coating weight of 2.0 to 2.5g/m²。

4. The high barrier composite film of claim 1 wherein the dry weight of the two-component solvent-free polyurethane adhesive layer is 1.5-1.6g/m²。

5. The high barrier composite film according to any one of claims 1 to 4, wherein the ink printed layer is an aqueous environmental ink.

6. A method for preparing a high barrier composite film according to any one of claims 1 to 5, comprising the steps of:

step one, preparing a high-temperature-resistant printing layer

Printing an ink layer on the inner surface of the biaxially oriented polyethylene film by adopting a gravure inner printing process;

coating PTFE coating liquid on the outer surface of the biaxially oriented polyethylene film in a full-page manner; wherein the coating roll is a gravure roller with the mesh depth of 45-55um and 150 lines/inch, and the PTFE dry-base coating weight is 2.0-2.5g/m²The coating speed is 100-; drying at 55-65 deg.C, and standing in aging chamber at 38-45 deg.C for 24-48 hr;

step two: preparation of a Barrier resistant base layer

Performing corona treatment on the surface of the low-density polyethylene film layer, and then coating a PVA coating on the corona treatment surface by adopting a coating machine; the coating roller of the coating machine is a gravure roller with the mesh depth of 45-55um and 150 lines/inch, and the dry-base coating weight of the PVA coating is 2.0-2.5g/m²The coating speed is 100-; drying at 65-75 deg.C, and standing in aging chamber at 38-45 deg.C for 24-48 hr;

step three: compounding

Preparing a double-component solvent-free polyurethane adhesive, wherein the mass ratio of the glue A to the glue B is 100: 70; bonding and compounding the high-temperature resistant printing layer and the barrier-resistant base layer with the double-component solvent-free polyurethane adhesive, wherein the temperature of the glue solution is 32-40 ℃, the compounding temperature is 32-40 ℃, and the gluing amount of the dry base is 1.5-1.6g/m²(ii) a Placing the mixture in a curing chamber at the temperature of 35-40 ℃ for 36-48 hours.

7. The method for preparing the high-barrier composite film according to claim 6, wherein the surface wetting tension of the low-density polyethylene film layer after corona treatment in the second step is more than or equal to 40 mN/m.

8. The use of the high-barrier composite film according to any one of claims 1 to 5, wherein the high-barrier composite film is used for manufacturing a packaging bag, and the hot pressing temperature for manufacturing the packaging bag is 130-200 ℃.