High-speed easy-to-cut aroma-keeping cigarette composite inner film and preparation process thereof
By using a three-layer composite inner film structure and a low-temperature BOPP formulation design, the problem of insufficient sealing and cutting performance of cigarette packaging inner film during high-speed packaging is solved, thereby improving high-speed packaging and aroma preservation effects.
Patent Information
- Application Number
- CN202511576230.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-31
- Publication Date
- 2026-03-10
AI Technical Summary
Existing cigarette packaging inner films have problems with insufficient sealing performance and poor cutting performance during high-speed packaging, and cannot meet the requirements of high-speed packaging.
The composite inner membrane adopts a three-layer structure, including an outer heat-sealing BOPP layer, an AL layer, and an inner heat-sealing BOPP layer. Through low-temperature BOPP formulation design, the outer heat-sealing BOPP layer and the inner heat-sealing BOPP layer are respectively composited with the AL layer, combined with a two-component polyurethane adhesive, to achieve low-temperature heat-sealing performance and easy cutting performance.
It achieves improved sealing and cutting performance in high-speed packaging, increasing packaging speed from 600 packs/min to 1000 packs/min, ensuring the aroma preservation effect of cigarettes.
Abstract
Description
Technical Field
[0001] This invention relates to the field of packaging materials technology, and in particular to a high-speed, easy-to-cut aroma-preserving composite inner film for cigarettes and its preparation process. Background Technology
[0002] Currently, most cigarette packaging inner films on the market are primarily composed of a paper and aluminum foil composite. Because of the aluminum foil, this type of inner film offers some aroma retention, resulting in relatively stable performance. However, as consumers demand higher aroma retention capabilities, this material exhibits the following drawbacks: 1. The composite film of paper and aluminum foil does not have a heat-sealing effect and can only be folded, but cannot be laminated, resulting in poor sealing performance. If it is replaced with BOPP film with heat-sealing properties, the starting temperature of the existing BOPP film is 110-120℃, while the starting temperature for high-speed packaging is 90-95℃, which cannot meet the requirements of high-speed packaging. 2. The existing cigarette packaging inner film is cut into pieces before packaging. Due to its low elongation at break and yield strength, the material has poor stiffness, which is not conducive to cutting. As a result, the packaging speed can only reach 500-700 packs / min. The high-speed packaging performance is insufficient, which affects the production efficiency. Summary of the Invention
[0003] To address the aforementioned technical problems, this invention provides a high-speed, easily cut aroma-preserving composite inner film for cigarettes and its preparation process. This composite inner film has a heat-sealing function and, through the design of a low-temperature BOPP formulation, is more suitable for high-speed packaging.
[0004] To achieve one of the objectives of this invention, the following technical solution is adopted: A high-speed, easily cut aroma-preserving cigarette composite inner film includes an outer heat-sealed BOPP layer, an AL layer, and an inner heat-sealed BOPP layer connected in sequence. Both the outer and inner heat-sealed BOPP layers consist of an air knife surface layer, an air knife sublayer, an intermediate layer, a roller-mounting sublayer, and a roller-mounting surface layer. The roller-mounting surface layers of the outer and inner heat-sealed BOPP layers are respectively bonded to both sides of the AL layer.
[0005] Preferably, the air knife surface is a heat-sealed surface, and the roller surface is a corona-electrode surface.
[0006] Preferably, the air knife surface layer is composed of 70 parts by mass of ternary copolymer polypropylene and 30 parts by mass of first polypropylene; the air knife surface sublayer, the intermediate layer and the roller-attaching surface sublayer are all composed of 100 parts by mass of homopolymer polypropylene; and the roller-attaching surface layer is composed of 90 parts by mass of second polypropylene and 10 parts by mass of third polypropylene.
[0007] Preferably, the grade of the ternary copolymer polypropylene is FS5612 produced by a Singapore company; the grade of the first polypropylene is XM7070S produced by Mitsui Chemicals, Inc. of Japan, which is a polypropylene (PP)-based heat-sealing film olefin resin, category PAO; the grade of the homopolymer polypropylene is HA849K produced by Basel Chemicals; the grade of the second polypropylene is F03G produced by Sinopec; and the grade of the third polypropylene is F8005 produced by Sinopec.
[0008] Preferably, the thickness of both the outer heat-sealing BOPP layer and the inner heat-sealing BOPP layer is 20 μm, and the thickness of the AL layer is 8 μm.
[0009] Preferably, both the outer heat-sealing BOPP layer and the inner heat-sealing BOPP layer are dry-laminated with a two-component polyurethane adhesive and an AL layer.
[0010] Preferably, the two-component polyurethane adhesive consists of a main agent and a curing agent, and the weight ratio of the main agent to the curing agent is 4:1.
[0011] Preferably, the main agent is YH3300 produced by Gaomeng Company; the curing agent is YH3300B produced by Gaomeng Company.
[0012] To achieve the second objective of this invention, this invention provides a process for preparing a high-speed, easily cut aroma-preserving cigarette composite inner film, which includes the following steps: S1. Weigh the raw materials of the outer heat-sealing BOPP layer and the inner heat-sealing BOPP layer and place them in the BOPP double-drawing equipment to obtain the outer heat-sealing BOPP layer and the inner heat-sealing BOPP layer respectively. S2. Using a two-component polyurethane adhesive, the outer heat-sealing BOPP layer and the inner heat-sealing BOPP layer are dry-laminated onto both sides of the AL layer, and then cured and cut in sequence to obtain the composite inner film.
[0013] Preferably, the adhesive application rate for dry lamination is 2.8-3.2 g / m³. 2 .
[0014] The advantages of this invention compared to the prior art are as follows: 1) This invention improves the problem that paper foil structures cannot be heat-sealed, and at the same time, through the design of a low-temperature BOPP formula, it is more suitable for high-speed packaging.
[0015] 2) Achieving high-speed packaging: The heat-sealable film offers low-temperature heat-sealing performance and enhances aroma retention. In addition to AL material, it achieves A and B sealing (outer and inner layer heat sealing), further improving aroma retention. The heat-sealable film formula not only focuses on low-temperature performance but also improves cutting performance, making it suitable for high-speed packaging. Through innovative formula design and guaranteed production processes, high-speed cutting is facilitated, increasing cigarette packaging production efficiency from 600 packs / min to 1000 packs / min. The design, with both inner and outer layers being heat-sealable, achieves a sealed aroma retention effect for the cigarettes.
[0016] 3) This invention uses a three-layer material composed of low-temperature heat-sealed BOPP and aluminum foil. The inner and outer layers are both low-temperature heat-sealed BOPP, and the middle layer is aluminum foil. The purpose of this design is to achieve a sealing effect through heat sealing of the inner and outer layers, which has better sealing performance than paper foil composite film and can play a role in preserving the aroma of cigarettes. The low-temperature heat-sealed BOPP formula not only needs to consider heat sealing strength, but also needs to meet the requirements of high-speed packaging performance and easy cutting performance. The packaging speed can reach 1000 packs / min. This material can be printed with patterns on BOPP film to enhance the product grade.
[0017] 4) This adhesive has good leveling properties, fast curing speed, and is easy to cut after curing. It is used for both inner and outer layers, which has a certain effect on the overall cutting performance of the product. Detailed Implementation
[0018] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.
[0019] Example 1 S1. Weigh the raw materials of the outer heat-sealing BOPP layer and the inner heat-sealing BOPP layer and place them in the BOPP double-drawing equipment to obtain the outer heat-sealing BOPP layer and the inner heat-sealing BOPP layer respectively. S2. Using a two-component polyurethane adhesive, the outer heat-sealing BOPP layer and the inner heat-sealing BOPP layer are dry-laminated onto both sides of the AL layer, and then cured and cut in sequence to obtain the composite inner film.
[0020] Both the outer and inner heat-sealed BOPP layers consist of an air knife surface layer, an air knife sublayer, an intermediate layer, a roller-attaching sublayer, and a roller-attaching surface layer. The roller-attaching surface layers of the outer and inner heat-sealed BOPP layers are respectively bonded to both sides of the AL layer. The air knife surface layer is the heat-sealing surface, and the roller-attaching surface layer is the corona-electrode surface. The air knife surface layer consists of 70 parts by weight of ternary copolymer polypropylene and 30 parts by weight of first polypropylene; the air knife sublayer, intermediate layer, and roller-attaching sublayer are all composed of 100 parts by weight of homopolymer polypropylene; the roller-attaching surface layer consists of 90 parts by weight of second polypropylene and 10 parts by weight of third polypropylene.
[0021] Specifically, the ternary copolymer polypropylene is FS5612 produced by a Singapore company; the first polypropylene is XM7070S produced by Mitsui Chemicals, Ltd. of Japan; the homopolymer polypropylene is HA849K produced by Basel Chemicals; the second polypropylene is F03G produced by Sinopec; and the third polypropylene is F8005 produced by Sinopec. The thickness of both the outer and inner heat-sealed BOPP layers is 20 μm, and the thickness of the AL layer is 8 μm. Both the outer and inner heat-sealed BOPP layers are dry-laminated with a two-component polyurethane adhesive to the AL layer. The two-component polyurethane adhesive consists of a main agent and a curing agent, with a weight ratio of 4:1. The main agent is YH3300 produced by Gaomeng Company; the curing agent is YH3300B produced by Gaomeng Company.
[0022] Comparative Example 1 Two 20μm heat-sealable BOPP films were dry-laminated onto the two sides of an 8μm AL layer using a two-component polyurethane adhesive, and then cured and slit sequentially to obtain the composite inner film; the heat-sealable BOPP film was produced by Anhui Guofeng Company.
[0023] The composite inner membranes prepared in Example 1 and Comparative Example 1 were subjected to performance tests, and the results are shown in Tables 1-2 below: Table 1 ; As can be seen from Table 1 above, the initial sealing temperature of the low-temperature heat-sealing composite film prepared in Example 1 is 95°C, while the initial sealing temperature of the heat-sealing composite film prepared in Comparative Example 1 for normal use is 120°C. The lower the initial sealing temperature, the better it can adapt to high-speed packaging performance. Therefore, the composite film prepared in Example 1 is more suitable for high-speed packaging.
[0024] Table 2 ; As can be seen from Table 2 above, the elongation at break and yield strength of the composite inner membrane prepared in Example 1 are higher than those of the composite inner membrane in Comparative Example 1. This indicates that the composite inner membrane prepared by the present invention has high stiffness and low thermal shrinkage, which means that it has low shrinkage under heat, is not easily deformed, and is more conducive to cutting.
[0025] This invention, through innovative formula design and guaranteed production process, facilitates high-speed cutting and improves the production efficiency of cigarette packaging, increasing the cigarette packaging capacity from 600 packs / min to 1000 packs / min. By designing both the inner and outer layers as heat-sealable films, it can achieve the effect of preserving the aroma of cigarettes.
Claims
1. A high speed easy-to-cut, flavor preserving cigarette composite inner wrapper, characterized by: The inner film comprises an outer heat-seal BOPP layer, an AL layer and an inner heat-seal BOPP layer connected in sequence, the outer heat-seal BOPP layer and the inner heat-seal BOPP layer each comprise a wind-knife surface layer, a wind-knife surface sub-layer, an intermediate layer, a sticking roller surface sub-layer and a sticking roller surface layer, and the sticking roller surface layer of the outer heat-seal BOPP layer and the sticking roller surface layer of the inner heat-seal BOPP layer are respectively combined with the two surfaces of the AL layer.
2. A high speed easy to cut, flavor preserving cigarette composite inner wrapper according to claim 1, characterized in that: The wind-knife surface layer is a heat-seal surface, and the sticking roller surface layer is a corona surface.
3. A high speed easy-to-cut, flavor preserving cigarette composite inner wrapper according to claim 1 or 2, characterized in that: The wind-knife surface layer is composed of 70 parts by mass of a terpolymer polypropylene and 30 parts by mass of a first polypropylene; the wind-knife surface sub-layer, the intermediate layer and the sticking roller surface sub-layer are each composed of 100 parts by mass of a homopolymer polypropylene; and the sticking roller surface layer is composed of 90 parts by mass of a second polypropylene and 10 parts by mass of a third polypropylene.
4. A high speed easy to cut, flavor preserving cigarette composite inner wrapper according to claim 3, characterized in that: The terpolymer polypropylene is FS5612 produced by a Singapore company; the first polypropylene is XM7070S produced by a Japanese Mitsui company; the homopolymer polypropylene is HA849K produced by a Basel company; the second polypropylene is F03G produced by a Sinopec company; and the third polypropylene is F8005 produced by a Sinopec company.
5. A high speed easy to cut, flavor preserving cigarette composite inner wrapper according to claim 1, characterized in that: The thickness of the outer heat-seal BOPP layer and the thickness of the inner heat-seal BOPP layer are each 20 μm, and the thickness of the AL layer is 8 μm.
6. A high speed easy to cut, flavor preserving cigarette composite inner wrapper according to claim 1, characterized in that: The outer heat-seal BOPP layer and the inner heat-seal BOPP layer are each dry-combined with the AL layer using a two-component polyurethane adhesive.
7. A high speed easy to cut, flavor preserving cigarette composite inner wrapper according to claim 6, characterized in that: The two-component polyurethane adhesive is composed of a main agent and a curing agent, and the weight ratio of the main agent to the curing agent is 4:
1.
8. A high speed easy to cut, flavor preserving cigarette composite inner wrapper according to claim 7, characterized in that: The main agent is YH3300 produced by a Gao Meng company, and the curing agent is YH3300B produced by the Gao Meng company.
9. The process for making a high speed easy cut, flavor preserving cigarette composite inner wrapper as claimed in any one of claims 1 to 8 wherein, The preparation process comprises the following steps: S1, placing raw materials of the outer heat-seal BOPP layer and the inner heat-seal BOPP layer in a BOPP double-drawing line device to respectively prepare the outer heat-seal BOPP layer and the inner heat-seal BOPP layer; S2, dry-combining the outer heat-seal BOPP layer and the inner heat-seal BOPP layer on the two surfaces of the AL layer respectively using a two-component polyurethane adhesive, and then sequentially performing curing and slitting to obtain a composite inner film.
10. The process for making a high speed easy to cut, flavor preserving cigarette composite inner wrapper as claimed in claim 9 wherein: The dry compounded sizing amount is 2.8-3.2 g / m 2 .