Work efficiency boosted by over 300%! The new cigarette pack inspection device is this efficient!

In February 2025, Zhang Jianmin, Party Secretary and Director of the State Tobacco Monopoly Administration and General Manager of China National Tobacco Corporation, emphasized during an inspection in Hunan Tobacco to 'further deepen reform and innovation, inject new momentum into high-quality development and modernization, and promote industrial innovation through technological innovation while continuously enhancing digital development capabilities.' This directive points the way for technological innovation in the cigarette packaging industry. 'Adhesive performance' is an important indicator of cigarette pack machine adaptability, as the strength of the adhesive layer directly determines the structural stability of cigarette packs throughout storage, transportation, and sales. According to a 2024 survey by the Tobacco Packaging Committee of the China Packaging Federation, the average scrap rate of domestic cigarette packs due to glue issues is 5.7%, with some small and medium-sized enterprises exceeding 15%, resulting in an annual direct economic loss of over 200 million yuan.

Currently, testing the adhesive performance of finished cigarette packs is entirely manual. The testing process involves three main steps: material preparation, paper adhesion, and peel-off evaluation, covering over ten actions such as cutting samples, applying glue, pressing, setting, peeling, and assessment, all depending completely on manual work. This traditional method has problems like inaccurate glue amounts, uneven application, misaligned paper, and insufficient pressing, which leads to long testing times, repeated trials, high labor intensity, and low efficiency. Some heating equipment also poses safety risks. To address these issues, Changde Jinpeng Printing Co., Ltd. (hereinafter referred to as 'Changde Jinpeng') adopted a 'joint effort of upstream and downstream industry enterprises' approach, successfully developing a packaging paper adhesive performance testing device through on-site benchmarking and collaborative innovation. This article systematically explains the background, technical plan, implementation results, and promotion value of the device, aiming to provide a reference for quality testing technological innovation in the industry.

Technical Background and Problem Analysis

01/ Technical Meaning of Adhesive Performance

Adhesive performance refers to the process based on the adhesive failure mechanism, simulating the adhesive pressing step in cigarette pack formation. Two samples are bonded together and then destructively peeled apart. If the paper fibers are pulled apart by the glue, the adhesive performance is considered qualified. This performance indicator directly reflects the compatibility between the adhesive and the paper substrate and is a key parameter for ensuring the stability of the packaging structure.

02/ Traditional Testing Methods and Their Problems

Currently, all cigarette boxes need adhesive performance testing before leaving the factory. The testing process can be divided into three main stages: 'material preparation,' 'paper adhesion,' and 'peel-off evaluation.' The specific operation steps include: take the sample to be tested from the sample bag → cut the adhesive area of the sample to 20mm × 50mm → draw glue with a syringe (as shown in Figure 1) → drop glue onto the adhesive area → spread glue evenly using a clean dropper → align the paper back with the glued area → heat press using a sealing device (as shown in Figure 2) → let it stand horizontally for 30 minutes → manually peel the two bonded surfaces completely apart → visually inspect to see if the paper fibers are damaged.

Figure 1 Manual Suction of Gel

Figure 2 Heat Sealing Press

After analysis, the above fully manual operation process has the following problems:

(1) Low efficiency: Single tests in the laboratory take too long, with the full process taking about 35 minutes. After a request for inspection, there's a long wait for feedback, which can't meet real-time production monitoring needs.

(2) Safety hazards: Some testing steps involve heating equipment, and manual operation carries risks like burns and electrical hazards.

(3) Insufficient accuracy: Current testing methods are relatively rough. Glue amount control relies on operator experience, and uniformity of coating can't be guaranteed, leading to low precision in test data, making it difficult to support refined quality control.

(4) High reinspection rate: The whole process is performed manually, and key steps (like scraping glue, alignment, and pressing) are prone to errors, causing experiment failure. The reinspection rate is as high as 50%, which not only increases workload but also wastes testing resources.

In summary, traditional manual testing methods are no longer suitable for the modern cigarette pack industry's requirements for precise and efficient quality control. There is an urgent need to develop a standardized, automated testing device to fundamentally eliminate human interference.

Solution and Technical Principles

01/ Research Goals and Overall Approach

To address the above issues, our project team set the following development goal: to develop a packaging paper adhesive performance testing device that standardizes and automates the testing process, effectively controls the amount and uniformity of glue applied, ensures safe and firm heated pressing, and significantly improves testing efficiency and data reliability. The overall technical approach is to integrate functions such as glue scraping, transferring, heating, and pressing into a single device, converting scattered manual operations into a continuous automated process; achieve precise control of key process parameters through a precise mechanical structure; and eliminate human factors through standardized operating procedures.

02/ Device Structural Design

The developed packaging paper adhesive performance testing device belongs to the field of packaging bonding technology and mainly includes three functional modules, as shown in Figure 3.

Figure 3 Packaging Paper Adhesive Performance Testing Device (left: schematic diagram, right: real device)

(1) Base: Serves as the supporting platform for the entire device, integrating the installation of the scraping mechanism, rolling mechanism, and lamination mechanism. It ensures the spatial positioning of each functional module is precisely coordinated, enabling continuous testing processes.

(2) Scraping mechanism: Used to scrape excess glue from the glue brush trough into the overflow trough and level the glue. This mechanism features a precise scraper gap adjustment device to control the glue layer thickness within a preset range, ensuring uniform and consistent thickness.

(3) Rolling mechanism: Used to press the packaging paper onto the glue layer after scraping, transferring the glue to the paper. The mechanism is controlled by a drive unit that ensures the roller applies glue at a constant speed and pressure, eliminating issues like speed fluctuation or uneven pressure from manual rolling.

(4) Lamination mechanism: Used during adhesive tests to apply controlled pressure and timing on the glued packaging paper placed in the lamination trough, simulating the lamination process in actual printing and packaging production. This mechanism includes an electric heating module to precisely control pressing temperature and time.

03/ Standardized Testing Process

Based on the developed device, the following standardized testing process was established:

(1) Sampling: At least 5 sheets should be sampled per batch. Samples should be flat, undamaged, free of sticking, and meet the size requirement of at least 300mm × 300mm. Each sample should indicate the paper grain direction and front/back sides, and be sealed in a bag.

(2) Temperature and humidity conditioning: Samples should be conditioned under the conditions specified in GB/T 10739 to eliminate environmental influences on the results.

(3) Sample cutting: Cut the samples into Sample 1 (98mm × 42mm) and Sample 2 (98mm × 50mm), ensuring the long side (98mm) is parallel to the grain direction for consistency with the production stress direction.

(4) Glue application: Use a glue extractor to take a fixed amount of glue and inject it into the dot glue reservoir of the adhesive sample preparation module.

(5) Scraping: The scraper automatically moves excess glue around the dot reservoir into the overflow trough and levels the glue, forming an evenly thick layer.

(6) Glue transfer: Place Sample 1 (98mm × 42mm) into the adhesive module with the front facing up. Start the roller mechanism to press the sample onto the leveled glue layer at a constant speed and pressure, ensuring uniform glue transfer.

(7) Lamination: Remove Sample 1 with glue and place it in the electric heating module slot of the lamination function, with the glued side facing up, aligned with the front side of Sample 2. Set the electric heating module temperature and start the hot-press device to press Sample 1 and Sample 2 together.

(8) Sample installation: Take the laminated sample from the adhesive device, place one end of Sample 2 into the fixed slot of the peel tester, and clamp the other end of Sample 1 with the traction fixture.

(9) Peel test: As shown in Figure 4, use a 150° peel angle and a testing speed of 600mm/s with the traction fixture. Record the peel force curve and determine the failure mode (paper fiber failure or glue interface failure).

Figure 4 Cigarette Pack Peeling Test

04/ Key Technology Breakthroughs

This device has achieved technological breakthroughs in the following three areas:

(1) Integrated Design: By integrating the three main functional modules-glue scraping, rolling, and laminating-into a single base, it standardizes the entire process in adhesive performance experiments, including applying glue, leveling the adhesive layer, transferring glue, and laminating, eliminating errors between steps.

(2) Precise Parameter Control: The scraping mechanism ensures the adhesive layer is uniform in thickness (error ≤ 0.01mm); the rolling mechanism, driven by a servo system, controls the rollers to transfer the adhesive at a constant speed and pressure, with speed accuracy of ±0.1mm/s and pressure accuracy of ±0.5N; the laminating mechanism can precisely adjust laminating pressure (±1N), temperature (±1℃), and time (±0.1s), accurately simulating actual production conditions.

(3) Standardized Operation: All operations are set through a human-machine interface, and after one-click start, the entire process is completed automatically. This completely eliminates defects caused by manual operation, such as inaccurate glue amount, uneven application, misaligned paper, or insufficient pressing, ensuring the repeatability and comparability of the test results. The comparison of the before-and-after testing process is shown in Figure 5.

Figure 5 Comparison of detection process before and after improvement

Technical Effects and Data Analysis

01/ Efficiency Improvement Analysis

After multiple computer-based verifications and actual tests, this device has achieved significant improvements in detection efficiency. The total time for a single detection decreased from 2057 seconds using traditional manual methods to 442 seconds, representing a 365.38% increase in work efficiency. The success rate of the entire detection process reached 100%, and the re-inspection rate dropped from 50% to 0, greatly reducing the labor intensity for operators.

02/ Detection Accuracy and Reliability

Customer feedback: "The design of this device is scientific and reasonable, easy to operate, highly precise, and stable. It effectively overcomes the delays and data deviations found in previous manual testing methods, providing strong technical support for enhancing our control over the adhesive quality of packaging paper."

03/ Safety Improvements

Traditional manual testing uses heating equipment like heat sealers, which pose risks of burns and electrical hazards. This device integrates the heating module into a closed composite structure, using thermal insulation and automatic temperature control. Operators do not need to touch high-temperature parts, completely eliminating the risk of burns.

Social Benefits and Application Value

01/ Direct Economic Benefits

By predicting the adhesive performance of paper in advance, this device effectively reduces waste and rework in packaging production. It is estimated that if widely applied across the industry, the scrap rate of finished cigarette packs due to adhesive issues could be reduced from an average of 5.7% to below 2%. At the same time, the improved detection efficiency can save significant labor costs, reducing labor costs per detection by about 80%.

02/ Technological Leadership

The standardized operation of this device can measure the adhesive performance of different types of glue and efficiently screen formulations suitable for cigarette pack paper, inks, and coating processes. This shortens the R&D cycle for glue selection and formula improvement, accurately addressing practical problems in cigarette pack production such as delamination, peeling, glue overflow, and sticking, and establishes a compatibility evaluation system between glue and cigarette pack paper.

03/ Industry Chain Synergy

The project adopts a joint approach across the upstream and downstream of the industry chain, integrating the technical, talent, and equipment resources of upstream glue R&D, midstream cigarette pack printing, and downstream cigarette packaging production enterprises. This breaks the information and technology barriers between each link, forming a full-chain technical optimization system from raw materials to finished products, promoting the cigarette packaging industry toward greater efficiency, precision, and intelligence, and enhancing the core competitiveness of the industry.

04/ Contribution to Industry Standardization

This project successfully developed China's first device for testing the adhesive performance of packaging paper, achieving an industry first. To meet the unified technical specifications required by different companies and testing institutions, the project team standardized the research results, promoting the technical advancement and quality improvement of folding cartons and raw materials (paper) in the packaging and printing industry, and enhancing the resource coordination and innovation capabilities across upstream and downstream enterprises.

In the future, the research team will continue to optimize the device's intelligence, developing an automatic evaluation system based on machine vision, achieving fully unmanned detection of adhesive performance, while exploring applications of the device for testing the adhesive properties of other packaging materials (such as plastic and metal foil), making greater contributions to innovation in packaging quality testing technology.